xref: /btstack/src/hci.c (revision 6ac9a97e5a07060ea6ebc98edf54d21d72b8bbc9)
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_non_flushable_packet_boundary_flag_supported(void){
488     // No. 54, byte 6, bit 6
489     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
490 }
491 
492 int hci_ssp_supported(void){
493     // No. 51, byte 6, bit 3
494     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
495 }
496 
497 int hci_classic_supported(void){
498     // No. 37, byte 4, bit 5, = No BR/EDR Support
499     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
500 }
501 
502 int hci_le_supported(void){
503 #ifdef HAVE_BLE
504     // No. 37, byte 4, bit 6 = LE Supported (Controller)
505     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
506 #else
507     return 0;
508 #endif
509 }
510 
511 // get addr type and address used in advertisement packets
512 void hci_le_advertisement_address(uint8_t * addr_type, bd_addr_t * addr){
513     *addr_type = hci_stack->adv_addr_type;
514     if (hci_stack->adv_addr_type){
515         memcpy(addr, hci_stack->adv_address, 6);
516     } else {
517         memcpy(addr, hci_stack->local_bd_addr, 6);
518     }
519 }
520 
521 #ifdef HAVE_BLE
522 static void le_handle_advertisement_report(uint8_t *packet, int size){
523     int num_reports = packet[3];
524     int i;
525     int total_data_length = 0;
526     int data_offset = 0;
527 
528     for (i=0; i<num_reports;i++){
529         total_data_length += packet[4+num_reports*8+i];
530     }
531 
532     for (i=0; i<num_reports;i++){
533         int pos = 0;
534         uint8_t data_length = packet[4+num_reports*8+i];
535         uint8_t event_size = 10 + data_length;
536         uint8_t event[2 + event_size ];
537         event[pos++] = GAP_LE_ADVERTISING_REPORT;
538         event[pos++] = event_size;
539         event[pos++] = packet[4+i]; // event_type;
540         event[pos++] = packet[4+num_reports+i]; // address_type;
541         memcpy(&event[pos], &packet[4+num_reports*2+i*6], 6); // bt address
542         pos += 6;
543         event[pos++] = packet[4+num_reports*9+total_data_length + i];
544         event[pos++] = data_length;
545         memcpy(&packet[4+num_reports*9+data_offset], &event[pos], data_length);
546         data_offset += data_length;
547         pos += data_length;
548         hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
549     }
550 }
551 #endif
552 
553 // avoid huge local variables
554 #ifndef EMBEDDED
555 static device_name_t device_name;
556 #endif
557 static void event_handler(uint8_t *packet, int size){
558 
559     uint16_t event_length = packet[1];
560 
561     // assert packet is complete
562     if (size != event_length + 2){
563         log_error("hci.c: event_handler called with event packet of wrong size %u, expected %u => dropping packet", size, event_length + 2);
564         return;
565     }
566 
567     bd_addr_t addr;
568     bd_addr_type_t addr_type;
569     uint8_t link_type;
570     hci_con_handle_t handle;
571     hci_connection_t * conn;
572     int i;
573 
574     // printf("HCI:EVENT:%02x\n", packet[0]);
575 
576     switch (packet[0]) {
577 
578         case HCI_EVENT_COMMAND_COMPLETE:
579             // get num cmd packets
580             // log_info("HCI_EVENT_COMMAND_COMPLETE cmds old %u - new %u\n", hci_stack->num_cmd_packets, packet[2]);
581             hci_stack->num_cmd_packets = packet[2];
582 
583             if (COMMAND_COMPLETE_EVENT(packet, hci_read_buffer_size)){
584                 // from offset 5
585                 // status
586                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
587                 hci_stack->acl_data_packet_length = READ_BT_16(packet, 6);
588                 // ignore: SCO data packet len (8)
589                 hci_stack->total_num_acl_packets  = packet[9];
590                 // ignore: total num SCO packets
591                 if (hci_stack->state == HCI_STATE_INITIALIZING){
592                     // determine usable ACL payload size
593                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->acl_data_packet_length){
594                         hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
595                     }
596                     log_info("hci_read_buffer_size: used size %u, count %u\n",
597                              hci_stack->acl_data_packet_length, hci_stack->total_num_acl_packets);
598                 }
599             }
600 #ifdef HAVE_BLE
601             if (COMMAND_COMPLETE_EVENT(packet, hci_le_read_buffer_size)){
602                 hci_stack->le_data_packet_length = READ_BT_16(packet, 6);
603                 hci_stack->total_num_le_packets  = packet[8];
604                 log_info("hci_le_read_buffer_size: size %u, count %u\n", hci_stack->le_data_packet_length, hci_stack->total_num_le_packets);
605             }
606 #endif
607             // Dump local address
608             if (COMMAND_COMPLETE_EVENT(packet, hci_read_bd_addr)) {
609                 bt_flip_addr(hci_stack->local_bd_addr, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1]);
610                 log_info("Local Address, Status: 0x%02x: Addr: %s\n",
611                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
612             }
613             if (COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
614                 hci_emit_discoverable_enabled(hci_stack->discoverable);
615             }
616             // Note: HCI init checks
617             if (COMMAND_COMPLETE_EVENT(packet, hci_read_local_supported_features)){
618                 memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
619                 log_info("Local Supported Features: 0x%02x%02x%02x%02x%02x%02x%02x%02x",
620                     hci_stack->local_supported_features[0], hci_stack->local_supported_features[1],
621                     hci_stack->local_supported_features[2], hci_stack->local_supported_features[3],
622                     hci_stack->local_supported_features[4], hci_stack->local_supported_features[5],
623                     hci_stack->local_supported_features[6], hci_stack->local_supported_features[7]);
624 
625                 // determine usable ACL packet types based buffer size and supported features
626                 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]);
627                 log_info("packet types %04x", hci_stack->packet_types);
628 
629                 // Classic/LE
630                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
631             }
632             break;
633 
634         case HCI_EVENT_COMMAND_STATUS:
635             // get num cmd packets
636             // log_info("HCI_EVENT_COMMAND_STATUS cmds - old %u - new %u\n", hci_stack->num_cmd_packets, packet[3]);
637             hci_stack->num_cmd_packets = packet[3];
638             break;
639 
640         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:
641             for (i=0; i<packet[2];i++){
642                 handle = READ_BT_16(packet, 3 + 2*i);
643                 uint16_t num_packets = READ_BT_16(packet, 3 + packet[2]*2 + 2*i);
644                 conn = hci_connection_for_handle(handle);
645                 if (!conn){
646                     log_error("hci_number_completed_packet lists unused con handle %u\n", handle);
647                     continue;
648                 }
649                 conn->num_acl_packets_sent -= num_packets;
650                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u\n", num_packets, handle, conn->num_acl_packets_sent);
651             }
652             break;
653 
654         case HCI_EVENT_CONNECTION_REQUEST:
655             bt_flip_addr(addr, &packet[2]);
656             // TODO: eval COD 8-10
657             link_type = packet[11];
658             log_info("Connection_incoming: %s, type %u\n", bd_addr_to_str(addr), link_type);
659             if (link_type == 1) { // ACL
660                 conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
661                 if (!conn) {
662                     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
663                 }
664                 if (!conn) {
665                     // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
666                     hci_stack->decline_reason = 0x0d;
667                     BD_ADDR_COPY(hci_stack->decline_addr, addr);
668                     break;
669                 }
670                 conn->state = RECEIVED_CONNECTION_REQUEST;
671                 hci_run();
672             } else {
673                 // SYNCHRONOUS CONNECTION LIMIT TO A DEVICE EXCEEDED (0X0A)
674                 hci_stack->decline_reason = 0x0a;
675                 BD_ADDR_COPY(hci_stack->decline_addr, addr);
676             }
677             break;
678 
679         case HCI_EVENT_CONNECTION_COMPLETE:
680             // Connection management
681             bt_flip_addr(addr, &packet[5]);
682             log_info("Connection_complete (status=%u) %s\n", packet[2], bd_addr_to_str(addr));
683             addr_type = BD_ADDR_TYPE_CLASSIC;
684             conn = hci_connection_for_bd_addr_and_type(&addr, addr_type);
685             if (conn) {
686                 if (!packet[2]){
687                     conn->state = OPEN;
688                     conn->con_handle = READ_BT_16(packet, 3);
689                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
690 
691                     // restart timer
692                     run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
693                     run_loop_add_timer(&conn->timeout);
694 
695                     log_info("New connection: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
696 
697                     hci_emit_nr_connections_changed();
698                 } else {
699                     // notify client if dedicated bonding
700                     if (conn->bonding_flags & BONDING_DEDICATED){
701                         hci_emit_dedicated_bonding_result(conn, packet[2]);
702                     }
703 
704                     // connection failed, remove entry
705                     linked_list_remove(&hci_stack->connections, (linked_item_t *) conn);
706                     btstack_memory_hci_connection_free( conn );
707 
708                     // if authentication error, also delete link key
709                     if (packet[2] == 0x05) {
710                         hci_drop_link_key_for_bd_addr(&addr);
711                     }
712                 }
713             }
714             break;
715 
716         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
717             handle = READ_BT_16(packet, 3);
718             conn = hci_connection_for_handle(handle);
719             if (!conn) break;
720             if (!packet[2]){
721                 uint8_t * features = &packet[5];
722                 if (features[6] & (1 << 3)){
723                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
724                 }
725             }
726             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
727             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x", conn->bonding_flags);
728             if (conn->bonding_flags & BONDING_DEDICATED){
729                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
730             }
731             break;
732 
733         case HCI_EVENT_LINK_KEY_REQUEST:
734             log_info("HCI_EVENT_LINK_KEY_REQUEST\n");
735             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
736             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
737             if (hci_stack->bondable && !hci_stack->remote_device_db) break;
738             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
739             hci_run();
740             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
741             return;
742 
743         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
744             bt_flip_addr(addr, &packet[2]);
745             conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
746             if (!conn) break;
747             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
748             link_key_type_t link_key_type = (link_key_type_t)packet[24];
749             // Change Connection Encryption keeps link key type
750             if (link_key_type != CHANGED_COMBINATION_KEY){
751                 conn->link_key_type = link_key_type;
752             }
753             if (!hci_stack->remote_device_db) break;
754             hci_stack->remote_device_db->put_link_key(&addr, (link_key_t *) &packet[8], conn->link_key_type);
755             // still forward event to allow dismiss of pairing dialog
756             break;
757         }
758 
759         case HCI_EVENT_PIN_CODE_REQUEST:
760             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
761             // non-bondable mode: pin code negative reply will be sent
762             if (!hci_stack->bondable){
763                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
764                 hci_run();
765                 return;
766             }
767             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
768             if (!hci_stack->remote_device_db) break;
769             bt_flip_addr(addr, &packet[2]);
770             hci_stack->remote_device_db->delete_link_key(&addr);
771             break;
772 
773         case HCI_EVENT_IO_CAPABILITY_REQUEST:
774             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
775             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
776             break;
777 
778         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
779             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
780             if (!hci_stack->ssp_auto_accept) break;
781             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
782             break;
783 
784         case HCI_EVENT_USER_PASSKEY_REQUEST:
785             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
786             if (!hci_stack->ssp_auto_accept) break;
787             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
788             break;
789 
790         case HCI_EVENT_ENCRYPTION_CHANGE:
791             handle = READ_BT_16(packet, 3);
792             conn = hci_connection_for_handle(handle);
793             if (!conn) break;
794             if (packet[2] == 0) {
795                 if (packet[5]){
796                     conn->authentication_flags |= CONNECTION_ENCRYPTED;
797                 } else {
798                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
799                 }
800             }
801             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
802             break;
803 
804         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
805             handle = READ_BT_16(packet, 3);
806             conn = hci_connection_for_handle(handle);
807             if (!conn) break;
808 
809             // dedicated bonding: send result and disconnect
810             if (conn->bonding_flags & BONDING_DEDICATED){
811                 conn->bonding_flags &= ~BONDING_DEDICATED;
812                 hci_emit_dedicated_bonding_result( conn, packet[2]);
813                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
814                 break;
815             }
816 
817             if (packet[2] == 0 && gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level){
818                 // link key sufficient for requested security
819                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
820                 break;
821             }
822             // not enough
823             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
824             break;
825 
826 #ifndef EMBEDDED
827         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
828             if (!hci_stack->remote_device_db) break;
829             if (packet[2]) break; // status not ok
830             bt_flip_addr(addr, &packet[3]);
831             // fix for invalid remote names - terminate on 0xff
832             for (i=0; i<248;i++){
833                 if (packet[9+i] == 0xff){
834                     packet[9+i] = 0;
835                     break;
836                 }
837             }
838             memset(&device_name, 0, sizeof(device_name_t));
839             strncpy((char*) device_name, (char*) &packet[9], 248);
840             hci_stack->remote_device_db->put_name(&addr, &device_name);
841             break;
842 
843         case HCI_EVENT_INQUIRY_RESULT:
844         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
845             if (!hci_stack->remote_device_db) break;
846             // first send inq result packet
847             hci_stack->packet_handler(HCI_EVENT_PACKET, packet, size);
848             // then send cached remote names
849             for (i=0; i<packet[2];i++){
850                 bt_flip_addr(addr, &packet[3+i*6]);
851                 if (hci_stack->remote_device_db->get_name(&addr, &device_name)){
852                     hci_emit_remote_name_cached(&addr, &device_name);
853                 }
854             }
855             return;
856 #endif
857 
858         case HCI_EVENT_DISCONNECTION_COMPLETE:
859             if (!packet[2]){
860                 handle = READ_BT_16(packet, 3);
861                 hci_connection_t * conn = hci_connection_for_handle(handle);
862                 if (conn) {
863                     hci_shutdown_connection(conn);
864                 }
865             }
866             break;
867 
868         case HCI_EVENT_HARDWARE_ERROR:
869             if(hci_stack->control && hci_stack->control->hw_error){
870                 (*hci_stack->control->hw_error)();
871             }
872             break;
873 
874         case DAEMON_EVENT_HCI_PACKET_SENT:
875             // free packet buffer for asynchronous transport
876             if (hci_transport_synchronous()) break;
877             hci_stack->hci_packet_buffer_reserved = 0;
878             break;
879 
880 #ifdef HAVE_BLE
881         case HCI_EVENT_LE_META:
882             switch (packet[2]){
883                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
884                     if (hci_stack->le_scanning_state != LE_SCANNING) break;
885                     le_handle_advertisement_report(packet, size);
886                     break;
887                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
888                     // Connection management
889                     bt_flip_addr(addr, &packet[8]);
890                     addr_type = (bd_addr_type_t)packet[7];
891                     log_info("LE Connection_complete (status=%u) type %u, %s\n", packet[3], addr_type, bd_addr_to_str(addr));
892                     // LE connections are auto-accepted, so just create a connection if there isn't one already
893                     conn = hci_connection_for_bd_addr_and_type(&addr, addr_type);
894                     if (packet[3]){
895                         if (conn){
896                             // outgoing connection failed, remove entry
897                             linked_list_remove(&hci_stack->connections, (linked_item_t *) conn);
898                             btstack_memory_hci_connection_free( conn );
899 
900                         }
901                         // if authentication error, also delete link key
902                         if (packet[3] == 0x05) {
903                             hci_drop_link_key_for_bd_addr(&addr);
904                         }
905                         break;
906                     }
907                     if (!conn){
908                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
909                     }
910                     if (!conn){
911                         // no memory
912                         break;
913                     }
914 
915                     conn->state = OPEN;
916                     conn->con_handle = READ_BT_16(packet, 4);
917 
918                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
919 
920                     // restart timer
921                     // run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
922                     // run_loop_add_timer(&conn->timeout);
923 
924                     log_info("New connection: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
925 
926                     hci_emit_nr_connections_changed();
927                     break;
928 
929             // printf("LE buffer size: %u, count %u\n", READ_BT_16(packet,6), packet[8]);
930 
931                 default:
932                     break;
933             }
934             break;
935 #endif
936 
937         default:
938             break;
939     }
940 
941     // handle BT initialization
942     if (hci_stack->state == HCI_STATE_INITIALIZING){
943         if (hci_stack->substate % 2){
944             // odd: waiting for event
945             if (packet[0] == HCI_EVENT_COMMAND_COMPLETE || packet[0] == HCI_EVENT_COMMAND_STATUS){
946                 // wait for explicit COMMAND COMPLETE on RESET
947                 if (hci_stack->substate > 1 || COMMAND_COMPLETE_EVENT(packet, hci_reset)) {
948                     hci_stack->substate++;
949                 }
950             }
951         }
952     }
953 
954     // help with BT sleep
955     if (hci_stack->state == HCI_STATE_FALLING_ASLEEP
956         && hci_stack->substate == 1
957         && COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
958         hci_stack->substate++;
959     }
960 
961     hci_stack->packet_handler(HCI_EVENT_PACKET, packet, size);
962 
963 	// execute main loop
964 	hci_run();
965 }
966 
967 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
968     switch (packet_type) {
969         case HCI_EVENT_PACKET:
970             event_handler(packet, size);
971             break;
972         case HCI_ACL_DATA_PACKET:
973             acl_handler(packet, size);
974             break;
975         default:
976             break;
977     }
978 }
979 
980 /** Register HCI packet handlers */
981 void hci_register_packet_handler(void (*handler)(uint8_t packet_type, uint8_t *packet, uint16_t size)){
982     hci_stack->packet_handler = handler;
983 }
984 
985 void hci_init(hci_transport_t *transport, void *config, bt_control_t *control, remote_device_db_t const* remote_device_db){
986 
987 #ifdef HAVE_MALLOC
988     if (!hci_stack) {
989         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
990     }
991 #else
992     hci_stack = &hci_stack_static;
993 #endif
994     memset(hci_stack, 0, sizeof(hci_stack_t));
995 
996     // reference to use transport layer implementation
997     hci_stack->hci_transport = transport;
998 
999     // references to used control implementation
1000     hci_stack->control = control;
1001 
1002     // reference to used config
1003     hci_stack->config = config;
1004 
1005     // no connections yet
1006     hci_stack->connections = NULL;
1007     hci_stack->discoverable = 0;
1008     hci_stack->connectable = 0;
1009     hci_stack->bondable = 1;
1010 
1011     // no pending cmds
1012     hci_stack->decline_reason = 0;
1013     hci_stack->new_scan_enable_value = 0xff;
1014 
1015     // higher level handler
1016     hci_stack->packet_handler = dummy_handler;
1017 
1018     // store and open remote device db
1019     hci_stack->remote_device_db = remote_device_db;
1020     if (hci_stack->remote_device_db) {
1021         hci_stack->remote_device_db->open();
1022     }
1023 
1024     // max acl payload size defined in config.h
1025     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1026 
1027     // register packet handlers with transport
1028     transport->register_packet_handler(&packet_handler);
1029 
1030     hci_stack->state = HCI_STATE_OFF;
1031 
1032     // class of device
1033     hci_stack->class_of_device = 0x007a020c; // Smartphone
1034 
1035     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
1036     hci_stack->ssp_enable = 1;
1037     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
1038     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
1039     hci_stack->ssp_auto_accept = 1;
1040 
1041     // LE
1042     hci_stack->adv_addr_type = 0;
1043     memset(hci_stack->adv_address, 0, 6);
1044     hci_stack->le_scanning_state = LE_SCAN_IDLE;
1045 }
1046 
1047 void hci_close(){
1048     // close remote device db
1049     if (hci_stack->remote_device_db) {
1050         hci_stack->remote_device_db->close();
1051     }
1052     while (hci_stack->connections) {
1053         hci_shutdown_connection((hci_connection_t *) hci_stack->connections);
1054     }
1055     hci_power_control(HCI_POWER_OFF);
1056 
1057 #ifdef HAVE_MALLOC
1058     free(hci_stack);
1059 #endif
1060     hci_stack = NULL;
1061 }
1062 
1063 void hci_set_class_of_device(uint32_t class_of_device){
1064     hci_stack->class_of_device = class_of_device;
1065 }
1066 
1067 void hci_disable_l2cap_timeout_check(){
1068     disable_l2cap_timeouts = 1;
1069 }
1070 // State-Module-Driver overview
1071 // state                    module  low-level
1072 // HCI_STATE_OFF             off      close
1073 // HCI_STATE_INITIALIZING,   on       open
1074 // HCI_STATE_WORKING,        on       open
1075 // HCI_STATE_HALTING,        on       open
1076 // HCI_STATE_SLEEPING,    off/sleep   close
1077 // HCI_STATE_FALLING_ASLEEP  on       open
1078 
1079 static int hci_power_control_on(void){
1080 
1081     // power on
1082     int err = 0;
1083     if (hci_stack->control && hci_stack->control->on){
1084         err = (*hci_stack->control->on)(hci_stack->config);
1085     }
1086     if (err){
1087         log_error( "POWER_ON failed\n");
1088         hci_emit_hci_open_failed();
1089         return err;
1090     }
1091 
1092     // open low-level device
1093     err = hci_stack->hci_transport->open(hci_stack->config);
1094     if (err){
1095         log_error( "HCI_INIT failed, turning Bluetooth off again\n");
1096         if (hci_stack->control && hci_stack->control->off){
1097             (*hci_stack->control->off)(hci_stack->config);
1098         }
1099         hci_emit_hci_open_failed();
1100         return err;
1101     }
1102     return 0;
1103 }
1104 
1105 static void hci_power_control_off(void){
1106 
1107     log_info("hci_power_control_off\n");
1108 
1109     // close low-level device
1110     hci_stack->hci_transport->close(hci_stack->config);
1111 
1112     log_info("hci_power_control_off - hci_transport closed\n");
1113 
1114     // power off
1115     if (hci_stack->control && hci_stack->control->off){
1116         (*hci_stack->control->off)(hci_stack->config);
1117     }
1118 
1119     log_info("hci_power_control_off - control closed\n");
1120 
1121     hci_stack->state = HCI_STATE_OFF;
1122 }
1123 
1124 static void hci_power_control_sleep(void){
1125 
1126     log_info("hci_power_control_sleep\n");
1127 
1128 #if 0
1129     // don't close serial port during sleep
1130 
1131     // close low-level device
1132     hci_stack->hci_transport->close(hci_stack->config);
1133 #endif
1134 
1135     // sleep mode
1136     if (hci_stack->control && hci_stack->control->sleep){
1137         (*hci_stack->control->sleep)(hci_stack->config);
1138     }
1139 
1140     hci_stack->state = HCI_STATE_SLEEPING;
1141 }
1142 
1143 static int hci_power_control_wake(void){
1144 
1145     log_info("hci_power_control_wake\n");
1146 
1147     // wake on
1148     if (hci_stack->control && hci_stack->control->wake){
1149         (*hci_stack->control->wake)(hci_stack->config);
1150     }
1151 
1152 #if 0
1153     // open low-level device
1154     int err = hci_stack->hci_transport->open(hci_stack->config);
1155     if (err){
1156         log_error( "HCI_INIT failed, turning Bluetooth off again\n");
1157         if (hci_stack->control && hci_stack->control->off){
1158             (*hci_stack->control->off)(hci_stack->config);
1159         }
1160         hci_emit_hci_open_failed();
1161         return err;
1162     }
1163 #endif
1164 
1165     return 0;
1166 }
1167 
1168 
1169 int hci_power_control(HCI_POWER_MODE power_mode){
1170 
1171     log_info("hci_power_control: %u, current mode %u\n", power_mode, hci_stack->state);
1172 
1173     int err = 0;
1174     switch (hci_stack->state){
1175 
1176         case HCI_STATE_OFF:
1177             switch (power_mode){
1178                 case HCI_POWER_ON:
1179                     err = hci_power_control_on();
1180                     if (err) return err;
1181                     // set up state machine
1182                     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
1183                     hci_stack->state = HCI_STATE_INITIALIZING;
1184                     hci_stack->substate = 0;
1185                     break;
1186                 case HCI_POWER_OFF:
1187                     // do nothing
1188                     break;
1189                 case HCI_POWER_SLEEP:
1190                     // do nothing (with SLEEP == OFF)
1191                     break;
1192             }
1193             break;
1194 
1195         case HCI_STATE_INITIALIZING:
1196             switch (power_mode){
1197                 case HCI_POWER_ON:
1198                     // do nothing
1199                     break;
1200                 case HCI_POWER_OFF:
1201                     // no connections yet, just turn it off
1202                     hci_power_control_off();
1203                     break;
1204                 case HCI_POWER_SLEEP:
1205                     // no connections yet, just turn it off
1206                     hci_power_control_sleep();
1207                     break;
1208             }
1209             break;
1210 
1211         case HCI_STATE_WORKING:
1212             switch (power_mode){
1213                 case HCI_POWER_ON:
1214                     // do nothing
1215                     break;
1216                 case HCI_POWER_OFF:
1217                     // see hci_run
1218                     hci_stack->state = HCI_STATE_HALTING;
1219                     break;
1220                 case HCI_POWER_SLEEP:
1221                     // see hci_run
1222                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
1223                     hci_stack->substate = 0;
1224                     break;
1225             }
1226             break;
1227 
1228         case HCI_STATE_HALTING:
1229             switch (power_mode){
1230                 case HCI_POWER_ON:
1231                     // set up state machine
1232                     hci_stack->state = HCI_STATE_INITIALIZING;
1233                     hci_stack->substate = 0;
1234                     break;
1235                 case HCI_POWER_OFF:
1236                     // do nothing
1237                     break;
1238                 case HCI_POWER_SLEEP:
1239                     // see hci_run
1240                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
1241                     hci_stack->substate = 0;
1242                     break;
1243             }
1244             break;
1245 
1246         case HCI_STATE_FALLING_ASLEEP:
1247             switch (power_mode){
1248                 case HCI_POWER_ON:
1249 
1250 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1251                     // nothing to do, if H4 supports power management
1252                     if (bt_control_iphone_power_management_enabled()){
1253                         hci_stack->state = HCI_STATE_INITIALIZING;
1254                         hci_stack->substate = HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP;
1255                         break;
1256                     }
1257 #endif
1258                     // set up state machine
1259                     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
1260                     hci_stack->state = HCI_STATE_INITIALIZING;
1261                     hci_stack->substate = 0;
1262                     break;
1263                 case HCI_POWER_OFF:
1264                     // see hci_run
1265                     hci_stack->state = HCI_STATE_HALTING;
1266                     break;
1267                 case HCI_POWER_SLEEP:
1268                     // do nothing
1269                     break;
1270             }
1271             break;
1272 
1273         case HCI_STATE_SLEEPING:
1274             switch (power_mode){
1275                 case HCI_POWER_ON:
1276 
1277 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1278                     // nothing to do, if H4 supports power management
1279                     if (bt_control_iphone_power_management_enabled()){
1280                         hci_stack->state = HCI_STATE_INITIALIZING;
1281                         hci_stack->substate = HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP;
1282                         hci_update_scan_enable();
1283                         break;
1284                     }
1285 #endif
1286                     err = hci_power_control_wake();
1287                     if (err) return err;
1288                     // set up state machine
1289                     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
1290                     hci_stack->state = HCI_STATE_INITIALIZING;
1291                     hci_stack->substate = 0;
1292                     break;
1293                 case HCI_POWER_OFF:
1294                     hci_stack->state = HCI_STATE_HALTING;
1295                     break;
1296                 case HCI_POWER_SLEEP:
1297                     // do nothing
1298                     break;
1299             }
1300             break;
1301     }
1302 
1303     // create internal event
1304 	hci_emit_state();
1305 
1306 	// trigger next/first action
1307 	hci_run();
1308 
1309     return 0;
1310 }
1311 
1312 static void hci_update_scan_enable(void){
1313     // 2 = page scan, 1 = inq scan
1314     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
1315     hci_run();
1316 }
1317 
1318 void hci_discoverable_control(uint8_t enable){
1319     if (enable) enable = 1; // normalize argument
1320 
1321     if (hci_stack->discoverable == enable){
1322         hci_emit_discoverable_enabled(hci_stack->discoverable);
1323         return;
1324     }
1325 
1326     hci_stack->discoverable = enable;
1327     hci_update_scan_enable();
1328 }
1329 
1330 void hci_connectable_control(uint8_t enable){
1331     if (enable) enable = 1; // normalize argument
1332 
1333     // don't emit event
1334     if (hci_stack->connectable == enable) return;
1335 
1336     hci_stack->connectable = enable;
1337     hci_update_scan_enable();
1338 }
1339 
1340 bd_addr_t * hci_local_bd_addr(void){
1341     return &hci_stack->local_bd_addr;
1342 }
1343 
1344 void hci_run(){
1345 
1346     hci_connection_t * connection;
1347     linked_item_t * it;
1348 
1349     if (!hci_can_send_packet_now_using_packet_buffer(HCI_COMMAND_DATA_PACKET)) return;
1350 
1351     // global/non-connection oriented commands
1352 
1353     // decline incoming connections
1354     if (hci_stack->decline_reason){
1355         uint8_t reason = hci_stack->decline_reason;
1356         hci_stack->decline_reason = 0;
1357         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
1358         return;
1359     }
1360 
1361     // send scan enable
1362     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
1363         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1364         hci_stack->new_scan_enable_value = 0xff;
1365         return;
1366     }
1367 
1368 #ifdef HAVE_BLE
1369     // handle le scan
1370     if (hci_stack->state == HCI_STATE_WORKING){
1371         switch(hci_stack->le_scanning_state){
1372             case LE_START_SCAN:
1373                 hci_stack->le_scanning_state = LE_SCANNING;
1374                 hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
1375                 return;
1376 
1377             case LE_STOP_SCAN:
1378                 hci_stack->le_scanning_state = LE_SCAN_IDLE;
1379                 hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
1380                 return;
1381             default:
1382                 break;
1383         }
1384     }
1385 #endif
1386 
1387     // send pending HCI commands
1388     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next){
1389         connection = (hci_connection_t *) it;
1390 
1391         if (connection->state == SEND_DISCONNECT){
1392             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
1393             connection->state = SENT_DISCONNECT;
1394             return;
1395         }
1396 
1397         if (connection->state == SEND_CREATE_CONNECTION){
1398             switch(connection->address_type){
1399                 case BD_ADDR_TYPE_CLASSIC:
1400                     log_info("sending hci_create_connection\n");
1401                     hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
1402                     break;
1403                 default:
1404 #ifdef HAVE_BLE
1405                     log_info("sending hci_le_create_connection\n");
1406                     hci_send_cmd(&hci_le_create_connection,
1407                                  1000,      // scan interval: 625 ms
1408                                  1000,      // scan interval: 625 ms
1409                                  0,         // don't use whitelist
1410                                  connection->address_type, // peer address type
1411                                  connection->address,       // peer bd addr
1412                                  0,         // our addr type: public
1413                                  80,        // conn interval min
1414                                  80,        // conn interval max (3200 * 0.625)
1415                                  0,         // conn latency
1416                                  2000,      // supervision timeout
1417                                  0,         // min ce length
1418                                  1000       // max ce length
1419                                  );
1420 
1421                     connection->state = SENT_CREATE_CONNECTION;
1422 #endif
1423                     break;
1424             }
1425             return;
1426         }
1427 
1428         if (connection->state == RECEIVED_CONNECTION_REQUEST){
1429             log_info("sending hci_accept_connection_request\n");
1430             connection->state = ACCEPTED_CONNECTION_REQUEST;
1431             hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
1432             return;
1433         }
1434 
1435         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
1436             log_info("responding to link key request\n");
1437             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
1438             link_key_t link_key;
1439             link_key_type_t link_key_type;
1440             if ( hci_stack->remote_device_db
1441               && hci_stack->remote_device_db->get_link_key( &connection->address, &link_key, &link_key_type)
1442               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
1443                connection->link_key_type = link_key_type;
1444                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
1445             } else {
1446                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
1447             }
1448             return;
1449         }
1450 
1451         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
1452             log_info("denying to pin request\n");
1453             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
1454             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
1455             return;
1456         }
1457 
1458         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
1459             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
1460             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
1461             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
1462                 // tweak authentication requirements
1463                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
1464                 if (connection->bonding_flags & BONDING_DEDICATED){
1465                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
1466                 }
1467                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
1468                     authreq |= 1;
1469                 }
1470                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
1471             } else {
1472                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
1473             }
1474             return;
1475         }
1476 
1477         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
1478             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
1479             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
1480             return;
1481         }
1482 
1483         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
1484             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
1485             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
1486             return;
1487         }
1488 
1489         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
1490             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
1491             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
1492             return;
1493         }
1494 
1495         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
1496             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
1497             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
1498             return;
1499         }
1500         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
1501             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
1502             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
1503             return;
1504         }
1505         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
1506             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
1507             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
1508             return;
1509         }
1510         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
1511             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
1512             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
1513             return;
1514         }
1515     }
1516 
1517     switch (hci_stack->state){
1518         case HCI_STATE_INITIALIZING:
1519             // log_info("hci_init: substate %u\n", hci_stack->substate);
1520             if (hci_stack->substate % 2) {
1521                 // odd: waiting for command completion
1522                 return;
1523             }
1524             switch (hci_stack->substate >> 1){
1525                 case 0: // RESET
1526                     hci_send_cmd(&hci_reset);
1527 
1528                     if (hci_stack->config == 0 || ((hci_uart_config_t *)hci_stack->config)->baudrate_main == 0){
1529                         // skip baud change
1530                         hci_stack->substate = 4; // >> 1 = 2
1531                     }
1532                     break;
1533                 case 1: // SEND BAUD CHANGE
1534                     hci_stack->control->baudrate_cmd(hci_stack->config, ((hci_uart_config_t *)hci_stack->config)->baudrate_main, hci_stack->hci_packet_buffer);
1535                     hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1536                     break;
1537                 case 2: // LOCAL BAUD CHANGE
1538                     hci_stack->hci_transport->set_baudrate(((hci_uart_config_t *)hci_stack->config)->baudrate_main);
1539                     hci_stack->substate += 2;
1540                     // break missing here for fall through
1541 
1542                 case 3:
1543                     // Custom initialization
1544                     if (hci_stack->control && hci_stack->control->next_cmd){
1545                         int valid_cmd = (*hci_stack->control->next_cmd)(hci_stack->config, hci_stack->hci_packet_buffer);
1546                         if (valid_cmd){
1547                             int size = 3 + hci_stack->hci_packet_buffer[2];
1548                             hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1549                             hci_stack->substate = 4; // more init commands
1550                             break;
1551                         }
1552                         log_info("hci_run: init script done\n\r");
1553                     }
1554                     // otherwise continue
1555 					hci_send_cmd(&hci_read_bd_addr);
1556 					break;
1557 				case 4:
1558 					hci_send_cmd(&hci_read_buffer_size);
1559 					break;
1560                 case 5:
1561                     hci_send_cmd(&hci_read_local_supported_features);
1562                     break;
1563                 case 6:
1564                     if (hci_le_supported()){
1565                         hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1566                     } else {
1567                         // Kensington Bluetoot 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1568                         hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1569                     }
1570 
1571                     // skip Classic init commands for LE only chipsets
1572                     if (!hci_classic_supported()){
1573                         if (hci_le_supported()){
1574                             hci_stack->substate = 11 << 1;    // skip all classic command
1575                         } else {
1576                             log_error("Neither BR/EDR nor LE supported");
1577                             hci_stack->substate = 13 << 1;    // skip all
1578                         }
1579                     }
1580                     break;
1581                 case 7:
1582                     if (hci_ssp_supported()){
1583                         hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1584                         break;
1585                     }
1586                     hci_stack->substate += 2;
1587                     // break missing here for fall through
1588 
1589                 case 8:
1590                     // ca. 15 sec
1591                     hci_send_cmd(&hci_write_page_timeout, 0x6000);
1592                     break;
1593                 case 9:
1594                     hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1595                     break;
1596                 case 10:
1597                     if (hci_stack->local_name){
1598                         hci_send_cmd(&hci_write_local_name, hci_stack->local_name);
1599                     } else {
1600                         char hostname[30];
1601 #ifdef EMBEDDED
1602                         // BTstack-11:22:33:44:55:66
1603                         strcpy(hostname, "BTstack ");
1604                         strcat(hostname, bd_addr_to_str(hci_stack->local_bd_addr));
1605                         printf("---> Name %s\n", hostname);
1606 #else
1607                         // hostname for POSIX systems
1608                         gethostname(hostname, 30);
1609                         hostname[29] = '\0';
1610 #endif
1611                         hci_send_cmd(&hci_write_local_name, hostname);
1612                     }
1613                     break;
1614                 case 11:
1615 					hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1616                     if (!hci_le_supported()){
1617                         // SKIP LE init for Classic only configuration
1618                         hci_stack->substate = 13 << 1;
1619                     }
1620 					break;
1621 
1622 #ifdef HAVE_BLE
1623                 // LE INIT
1624                 case 12:
1625                     hci_send_cmd(&hci_le_read_buffer_size);
1626                     break;
1627                 case 13:
1628                     // LE Supported Host = 1, Simultaneous Host = 0
1629                     hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1630                     break;
1631 #endif
1632 
1633                 // DONE
1634                 case 14:
1635                     // done.
1636                     hci_stack->state = HCI_STATE_WORKING;
1637                     hci_emit_state();
1638                     break;
1639                 default:
1640                     break;
1641             }
1642             hci_stack->substate++;
1643             break;
1644 
1645         case HCI_STATE_HALTING:
1646 
1647             log_info("HCI_STATE_HALTING\n");
1648             // close all open connections
1649             connection =  (hci_connection_t *) hci_stack->connections;
1650             if (connection){
1651 
1652                 // send disconnect
1653                 if (!hci_can_send_packet_now_using_packet_buffer(HCI_COMMAND_DATA_PACKET)) return;
1654 
1655                 log_info("HCI_STATE_HALTING, connection %p, handle %u\n", connection, (uint16_t)connection->con_handle);
1656                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
1657 
1658                 // send disconnected event right away - causes higher layer connections to get closed, too.
1659                 hci_shutdown_connection(connection);
1660                 return;
1661             }
1662             log_info("HCI_STATE_HALTING, calling off\n");
1663 
1664             // switch mode
1665             hci_power_control_off();
1666 
1667             log_info("HCI_STATE_HALTING, emitting state\n");
1668             hci_emit_state();
1669             log_info("HCI_STATE_HALTING, done\n");
1670             break;
1671 
1672         case HCI_STATE_FALLING_ASLEEP:
1673             switch(hci_stack->substate) {
1674                 case 0:
1675                     log_info("HCI_STATE_FALLING_ASLEEP\n");
1676                     // close all open connections
1677                     connection =  (hci_connection_t *) hci_stack->connections;
1678 
1679 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1680                     // don't close connections, if H4 supports power management
1681                     if (bt_control_iphone_power_management_enabled()){
1682                         connection = NULL;
1683                     }
1684 #endif
1685                     if (connection){
1686 
1687                         // send disconnect
1688                         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1689 
1690                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u\n", connection, (uint16_t)connection->con_handle);
1691                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
1692 
1693                         // send disconnected event right away - causes higher layer connections to get closed, too.
1694                         hci_shutdown_connection(connection);
1695                         return;
1696                     }
1697 
1698                     if (hci_classic_supported()){
1699                         // disable page and inquiry scan
1700                         if (!hci_can_send_packet_now_using_packet_buffer(HCI_COMMAND_DATA_PACKET)) return;
1701 
1702                         log_info("HCI_STATE_HALTING, disabling inq scans\n");
1703                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
1704 
1705                         // continue in next sub state
1706                         hci_stack->substate++;
1707                         break;
1708                     }
1709                     // fall through for ble-only chips
1710 
1711                 case 2:
1712                     log_info("HCI_STATE_HALTING, calling sleep\n");
1713 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1714                     // don't actually go to sleep, if H4 supports power management
1715                     if (bt_control_iphone_power_management_enabled()){
1716                         // SLEEP MODE reached
1717                         hci_stack->state = HCI_STATE_SLEEPING;
1718                         hci_emit_state();
1719                         break;
1720                     }
1721 #endif
1722                     // switch mode
1723                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
1724                     hci_emit_state();
1725                     break;
1726 
1727                 default:
1728                     break;
1729             }
1730             break;
1731 
1732         default:
1733             break;
1734     }
1735 }
1736 
1737 int hci_send_cmd_packet(uint8_t *packet, int size){
1738     bd_addr_t addr;
1739     hci_connection_t * conn;
1740     // house-keeping
1741 
1742     // create_connection?
1743     if (IS_COMMAND(packet, hci_create_connection)){
1744         bt_flip_addr(addr, &packet[3]);
1745         log_info("Create_connection to %s\n", bd_addr_to_str(addr));
1746 
1747         conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
1748         if (!conn){
1749             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
1750             if (!conn){
1751                 // notify client that alloc failed
1752                 hci_emit_connection_complete(conn, BTSTACK_MEMORY_ALLOC_FAILED);
1753                 return 0; // don't sent packet to controller
1754             }
1755             conn->state = SEND_CREATE_CONNECTION;
1756         }
1757         log_info("conn state %u", conn->state);
1758         switch (conn->state){
1759             // if connection active exists
1760             case OPEN:
1761                 // and OPEN, emit connection complete command, don't send to controller
1762                 hci_emit_connection_complete(conn, 0);
1763                 return 0;
1764             case SEND_CREATE_CONNECTION:
1765                 // connection created by hci, e.g. dedicated bonding
1766                 break;
1767             default:
1768                 // otherwise, just ignore as it is already in the open process
1769                 return 0;
1770         }
1771         conn->state = SENT_CREATE_CONNECTION;
1772     }
1773 
1774     if (IS_COMMAND(packet, hci_link_key_request_reply)){
1775         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
1776     }
1777     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
1778         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
1779     }
1780 
1781     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
1782         if (hci_stack->remote_device_db){
1783             bt_flip_addr(addr, &packet[3]);
1784             hci_stack->remote_device_db->delete_link_key(&addr);
1785         }
1786     }
1787 
1788     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
1789     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
1790         bt_flip_addr(addr, &packet[3]);
1791         conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
1792         if (conn){
1793             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
1794         }
1795     }
1796 
1797     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
1798     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
1799     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
1800     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
1801         bt_flip_addr(addr, &packet[3]);
1802         conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
1803         if (conn){
1804             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
1805         }
1806     }
1807 
1808 #ifdef HAVE_BLE
1809     if (IS_COMMAND(packet, hci_le_set_advertising_parameters)){
1810         hci_stack->adv_addr_type = packet[8];
1811     }
1812     if (IS_COMMAND(packet, hci_le_set_random_address)){
1813         bt_flip_addr(hci_stack->adv_address, &packet[3]);
1814     }
1815 #endif
1816 
1817     hci_stack->num_cmd_packets--;
1818     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
1819 
1820     // free packet buffer for synchronous transport implementations
1821     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
1822         hci_stack->hci_packet_buffer_reserved = 0;
1823     }
1824 
1825     return err;
1826 }
1827 
1828 // disconnect because of security block
1829 void hci_disconnect_security_block(hci_con_handle_t con_handle){
1830     hci_connection_t * connection = hci_connection_for_handle(con_handle);
1831     if (!connection) return;
1832     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
1833 }
1834 
1835 
1836 // Configure Secure Simple Pairing
1837 
1838 // enable will enable SSP during init
1839 void hci_ssp_set_enable(int enable){
1840     hci_stack->ssp_enable = enable;
1841 }
1842 
1843 int hci_local_ssp_activated(){
1844     return hci_ssp_supported() && hci_stack->ssp_enable;
1845 }
1846 
1847 // if set, BTstack will respond to io capability request using authentication requirement
1848 void hci_ssp_set_io_capability(int io_capability){
1849     hci_stack->ssp_io_capability = io_capability;
1850 }
1851 void hci_ssp_set_authentication_requirement(int authentication_requirement){
1852     hci_stack->ssp_authentication_requirement = authentication_requirement;
1853 }
1854 
1855 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
1856 void hci_ssp_set_auto_accept(int auto_accept){
1857     hci_stack->ssp_auto_accept = auto_accept;
1858 }
1859 
1860 /**
1861  * pre: numcmds >= 0 - it's allowed to send a command to the controller
1862  */
1863 int hci_send_cmd(const hci_cmd_t *cmd, ...){
1864     va_list argptr;
1865     va_start(argptr, cmd);
1866     uint16_t size = hci_create_cmd_internal(hci_stack->hci_packet_buffer, cmd, argptr);
1867     va_end(argptr);
1868     return hci_send_cmd_packet(hci_stack->hci_packet_buffer, size);
1869 }
1870 
1871 // Create various non-HCI events.
1872 // TODO: generalize, use table similar to hci_create_command
1873 
1874 void hci_emit_state(){
1875     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
1876     uint8_t event[3];
1877     event[0] = BTSTACK_EVENT_STATE;
1878     event[1] = sizeof(event) - 2;
1879     event[2] = hci_stack->state;
1880     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1881     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1882 }
1883 
1884 void hci_emit_connection_complete(hci_connection_t *conn, uint8_t status){
1885     uint8_t event[13];
1886     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
1887     event[1] = sizeof(event) - 2;
1888     event[2] = status;
1889     bt_store_16(event, 3, conn->con_handle);
1890     bt_flip_addr(&event[5], conn->address);
1891     event[11] = 1; // ACL connection
1892     event[12] = 0; // encryption disabled
1893     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
1894     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1895 }
1896 
1897 void hci_emit_le_connection_complete(hci_connection_t *conn, uint8_t status){
1898     uint8_t event[21];
1899     event[0] = HCI_EVENT_LE_META;
1900     event[1] = sizeof(event) - 2;
1901     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
1902     event[3] = status;
1903     bt_store_16(event, 4, conn->con_handle);
1904     event[6] = 0; // TODO: role
1905     event[7] = conn->address_type;
1906     bt_flip_addr(&event[8], conn->address);
1907     bt_store_16(event, 14, 0); // interval
1908     bt_store_16(event, 16, 0); // latency
1909     bt_store_16(event, 18, 0); // supervision timeout
1910     event[20] = 0; // master clock accuracy
1911     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
1912     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1913 }
1914 
1915 void hci_emit_disconnection_complete(uint16_t handle, uint8_t reason){
1916     uint8_t event[6];
1917     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
1918     event[1] = sizeof(event) - 2;
1919     event[2] = 0; // status = OK
1920     bt_store_16(event, 3, handle);
1921     event[5] = reason;
1922     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
1923     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1924 }
1925 
1926 void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
1927     if (disable_l2cap_timeouts) return;
1928     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
1929     uint8_t event[4];
1930     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
1931     event[1] = sizeof(event) - 2;
1932     bt_store_16(event, 2, conn->con_handle);
1933     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
1934     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1935 }
1936 
1937 void hci_emit_nr_connections_changed(){
1938     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
1939     uint8_t event[3];
1940     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
1941     event[1] = sizeof(event) - 2;
1942     event[2] = nr_hci_connections();
1943     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1944     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1945 }
1946 
1947 void hci_emit_hci_open_failed(){
1948     log_info("BTSTACK_EVENT_POWERON_FAILED");
1949     uint8_t event[2];
1950     event[0] = BTSTACK_EVENT_POWERON_FAILED;
1951     event[1] = sizeof(event) - 2;
1952     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1953     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1954 }
1955 
1956 #ifndef EMBEDDED
1957 void hci_emit_btstack_version() {
1958     log_info("BTSTACK_EVENT_VERSION %u.%u", BTSTACK_MAJOR, BTSTACK_MINOR);
1959     uint8_t event[6];
1960     event[0] = BTSTACK_EVENT_VERSION;
1961     event[1] = sizeof(event) - 2;
1962     event[2] = BTSTACK_MAJOR;
1963     event[3] = BTSTACK_MINOR;
1964     bt_store_16(event, 4, BTSTACK_REVISION);
1965     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1966     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1967 }
1968 #endif
1969 
1970 void hci_emit_system_bluetooth_enabled(uint8_t enabled){
1971     log_info("BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED %u", enabled);
1972     uint8_t event[3];
1973     event[0] = BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED;
1974     event[1] = sizeof(event) - 2;
1975     event[2] = enabled;
1976     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1977     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1978 }
1979 
1980 void hci_emit_remote_name_cached(bd_addr_t *addr, device_name_t *name){
1981     uint8_t event[2+1+6+248+1]; // +1 for \0 in log_info
1982     event[0] = BTSTACK_EVENT_REMOTE_NAME_CACHED;
1983     event[1] = sizeof(event) - 2 - 1;
1984     event[2] = 0;   // just to be compatible with HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
1985     bt_flip_addr(&event[3], *addr);
1986     memcpy(&event[9], name, 248);
1987 
1988     event[9+248] = 0;   // assert \0 for log_info
1989     log_info("BTSTACK_EVENT_REMOTE_NAME_CACHED %s = '%s'", bd_addr_to_str(*addr), &event[9]);
1990 
1991     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event)-1);
1992     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event)-1);
1993 }
1994 
1995 void hci_emit_discoverable_enabled(uint8_t enabled){
1996     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
1997     uint8_t event[3];
1998     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
1999     event[1] = sizeof(event) - 2;
2000     event[2] = enabled;
2001     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2002     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2003 }
2004 
2005 void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
2006     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
2007     uint8_t event[5];
2008     int pos = 0;
2009     event[pos++] = GAP_SECURITY_LEVEL;
2010     event[pos++] = sizeof(event) - 2;
2011     bt_store_16(event, 2, con_handle);
2012     pos += 2;
2013     event[pos++] = level;
2014     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2015     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2016 }
2017 
2018 void hci_emit_dedicated_bonding_result(hci_connection_t * connection, uint8_t status){
2019     log_info("hci_emit_dedicated_bonding_result %u ", status);
2020     uint8_t event[9];
2021     int pos = 0;
2022     event[pos++] = GAP_DEDICATED_BONDING_COMPLETED;
2023     event[pos++] = sizeof(event) - 2;
2024     event[pos++] = status;
2025     bt_flip_addr( * (bd_addr_t *) &event[pos], connection->address);
2026     pos += 6;
2027     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2028     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2029 }
2030 
2031 // query if remote side supports SSP
2032 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
2033     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2034     if (!connection) return 0;
2035     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
2036 }
2037 
2038 int hci_ssp_supported_on_both_sides(hci_con_handle_t handle){
2039     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
2040 }
2041 
2042 // GAP API
2043 /**
2044  * @bbrief enable/disable bonding. default is enabled
2045  * @praram enabled
2046  */
2047 void gap_set_bondable_mode(int enable){
2048     hci_stack->bondable = enable ? 1 : 0;
2049 }
2050 
2051 /**
2052  * @brief map link keys to security levels
2053  */
2054 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
2055     switch (link_key_type){
2056         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
2057             return LEVEL_4;
2058         case COMBINATION_KEY:
2059         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
2060             return LEVEL_3;
2061         default:
2062             return LEVEL_2;
2063     }
2064 }
2065 
2066 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
2067     if (!connection) return LEVEL_0;
2068     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
2069     return gap_security_level_for_link_key_type(connection->link_key_type);
2070 }
2071 
2072 
2073 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
2074     printf("gap_mitm_protection_required_for_security_level %u\n", level);
2075     return level > LEVEL_2;
2076 }
2077 
2078 /**
2079  * @brief get current security level
2080  */
2081 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
2082     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2083     if (!connection) return LEVEL_0;
2084     return gap_security_level_for_connection(connection);
2085 }
2086 
2087 /**
2088  * @brief request connection to device to
2089  * @result GAP_AUTHENTICATION_RESULT
2090  */
2091 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
2092     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2093     if (!connection){
2094         hci_emit_security_level(con_handle, LEVEL_0);
2095         return;
2096     }
2097     gap_security_level_t current_level = gap_security_level(con_handle);
2098     log_info("gap_request_security_level %u, current level %u", requested_level, current_level);
2099     if (current_level >= requested_level){
2100         hci_emit_security_level(con_handle, current_level);
2101         return;
2102     }
2103 
2104     connection->requested_security_level = requested_level;
2105 
2106     // would enabling ecnryption suffice (>= LEVEL_2)?
2107     if (hci_stack->remote_device_db){
2108         link_key_type_t link_key_type;
2109         link_key_t      link_key;
2110         if (hci_stack->remote_device_db->get_link_key( &connection->address, &link_key, &link_key_type)){
2111             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
2112                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2113                 return;
2114             }
2115         }
2116     }
2117 
2118     // try to authenticate connection
2119     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2120     hci_run();
2121 }
2122 
2123 /**
2124  * @brief start dedicated bonding with device. disconnect after bonding
2125  * @param device
2126  * @param request MITM protection
2127  * @result GAP_DEDICATED_BONDING_COMPLETE
2128  */
2129 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
2130 
2131     // create connection state machine
2132     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
2133 
2134     if (!connection){
2135         return BTSTACK_MEMORY_ALLOC_FAILED;
2136     }
2137 
2138     // delete linkn key
2139     hci_drop_link_key_for_bd_addr( (bd_addr_t *) &device);
2140 
2141     // configure LEVEL_2/3, dedicated bonding
2142     connection->state = SEND_CREATE_CONNECTION;
2143     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
2144     printf("gap_dedicated_bonding, mitm %u -> level %u\n", mitm_protection_required, connection->requested_security_level);
2145     connection->bonding_flags = BONDING_DEDICATED;
2146 
2147     // wait for GAP Security Result and send GAP Dedicated Bonding complete
2148 
2149     // handle: connnection failure (connection complete != ok)
2150     // handle: authentication failure
2151     // handle: disconnect on done
2152 
2153     hci_run();
2154 
2155     return 0;
2156 }
2157 
2158 void gap_set_local_name(const char * local_name){
2159     hci_stack->local_name = local_name;
2160 }
2161 
2162 le_command_status_t le_central_start_scan(){
2163     if (hci_stack->le_scanning_state == LE_SCANNING) return BLE_PERIPHERAL_OK;
2164     hci_stack->le_scanning_state = LE_START_SCAN;
2165     hci_run();
2166     return BLE_PERIPHERAL_OK;
2167 }
2168 
2169 le_command_status_t le_central_stop_scan(){
2170     if ( hci_stack->le_scanning_state == LE_SCAN_IDLE) return BLE_PERIPHERAL_OK;
2171     hci_stack->le_scanning_state = LE_STOP_SCAN;
2172     hci_run();
2173     return BLE_PERIPHERAL_OK;
2174 }
2175 
2176 
2177 le_command_status_t le_central_connect(bd_addr_t * addr, bd_addr_type_t addr_type){
2178     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2179     log_info("le_central_connect, conn struct %p", conn);
2180     if (!conn){
2181         conn = create_connection_for_bd_addr_and_type(*addr, addr_type);
2182         if (!conn){
2183             // notify client that alloc failed
2184             hci_emit_le_connection_complete(conn, BTSTACK_MEMORY_ALLOC_FAILED);
2185             return BLE_PERIPHERAL_NOT_CONNECTED; // don't sent packet to controller
2186         }
2187         conn->state = SEND_CREATE_CONNECTION;
2188         log_info("le_central_connect, state %u", conn->state);
2189         hci_run();
2190         return BLE_PERIPHERAL_OK;
2191     }
2192     log_info("le_central_connect, state %u", conn->state);
2193     hci_emit_le_connection_complete(conn, 0);
2194     hci_run();
2195     return BLE_PERIPHERAL_OK;
2196 }
2197 
2198 
2199 le_command_status_t gap_disconnect(hci_con_handle_t handle){
2200     hci_connection_t * conn = hci_connection_for_handle(handle);
2201     if (!conn){
2202         hci_emit_le_connection_complete(conn, 0);
2203         return BLE_PERIPHERAL_OK;
2204     }
2205     conn->state = SEND_DISCONNECT;
2206     hci_run();
2207     return BLE_PERIPHERAL_OK;
2208 }
2209