xref: /btstack/src/hci.c (revision 10e830c9829089835359a8001c707872cbfae197)
1 /*
2  * Copyright (C) 2009 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  *
17  * THIS SOFTWARE IS PROVIDED BY MATTHIAS RINGWALD AND CONTRIBUTORS
18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
20  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
21  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
23  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
24  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
25  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
27  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  */
31 
32 /*
33  *  hci.c
34  *
35  *  Created by Matthias Ringwald on 4/29/09.
36  *
37  */
38 
39 #include "hci.h"
40 
41 #include <unistd.h>
42 #include <stdarg.h>
43 #include <string.h>
44 #include <stdio.h>
45 
46 #include "debug.h"
47 #include "hci_dump.h"
48 
49 #include "../include/btstack/hci_cmds.h"
50 #include "../include/btstack/version.h"
51 
52 // temp
53 #include "l2cap.h"
54 
55 #define HCI_CONNECTION_TIMEOUT_MS 10000
56 
57 // the STACK is here
58 static hci_stack_t       hci_stack;
59 
60 /**
61  * get connection for a given handle
62  *
63  * @return connection OR NULL, if not found
64  */
65 hci_connection_t * connection_for_handle(hci_con_handle_t con_handle){
66     linked_item_t *it;
67     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
68         if ( ((hci_connection_t *) it)->con_handle == con_handle){
69             return (hci_connection_t *) it;
70         }
71     }
72     return NULL;
73 }
74 
75 static void hci_connection_timeout_handler(timer_source_t *timer){
76     hci_connection_t * connection = linked_item_get_user(&timer->item);
77     struct timeval tv;
78     gettimeofday(&tv, NULL);
79     if (tv.tv_sec >= connection->timestamp.tv_sec + HCI_CONNECTION_TIMEOUT_MS/1000) {
80         // connections might be timed out
81         hci_emit_l2cap_check_timeout(connection);
82         run_loop_set_timer(timer, HCI_CONNECTION_TIMEOUT_MS);
83     } else {
84         // next timeout check at
85         timer->timeout.tv_sec = connection->timestamp.tv_sec + HCI_CONNECTION_TIMEOUT_MS/1000;
86     }
87     run_loop_add_timer(timer);
88 }
89 
90 static void hci_connection_timestamp(hci_connection_t *connection){
91     gettimeofday(&connection->timestamp, NULL);
92 }
93 
94 /**
95  * create connection for given address
96  *
97  * @return connection OR NULL, if not found
98  */
99 static hci_connection_t * create_connection_for_addr(bd_addr_t addr){
100     hci_connection_t * conn = malloc( sizeof(hci_connection_t) );
101     if (!conn) return NULL;
102     BD_ADDR_COPY(conn->address, addr);
103     conn->con_handle = 0xffff;
104     conn->flags = 0;
105     linked_item_set_user(&conn->timeout.item, conn);
106     conn->timeout.process = hci_connection_timeout_handler;
107     hci_connection_timestamp(conn);
108     conn->acl_recombination_length = 0;
109     conn->acl_recombination_pos = 0;
110     linked_list_add(&hci_stack.connections, (linked_item_t *) conn);
111     return conn;
112 }
113 
114 /**
115  * get connection for given address
116  *
117  * @return connection OR NULL, if not found
118  */
119 static hci_connection_t * connection_for_address(bd_addr_t address){
120     linked_item_t *it;
121     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
122         if ( ! BD_ADDR_CMP( ((hci_connection_t *) it)->address, address) ){
123             return (hci_connection_t *) it;
124         }
125     }
126     return NULL;
127 }
128 
129 /**
130  * count connections
131  */
132 static int nr_hci_connections(){
133     int count = 0;
134     linked_item_t *it;
135     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next, count++);
136     return count;
137 }
138 
139 /**
140  * Dummy handler called by HCI
141  */
142 static void dummy_handler(uint8_t *packet, uint16_t size){
143 }
144 
145 /**
146  * Dummy control handler
147  */
148 static int null_control_function(void *config){
149     return 0;
150 }
151 static const char * null_control_name(void *config){
152     return "Hardware unknown";
153 }
154 static bt_control_t null_control = {
155     null_control_function,
156     null_control_function,
157     null_control_function,
158     null_control_name
159 };
160 
161 
162 int hci_send_acl_packet(uint8_t *packet, int size){
163 
164     // update idle timestamp
165     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
166     hci_connection_t *connection = connection_for_handle( con_handle);
167     if (connection) hci_connection_timestamp(connection);
168 
169     // send packet
170     return hci_stack.hci_transport->send_acl_packet(packet, size);
171 }
172 
173 static void acl_handler(uint8_t *packet, int size){
174 
175     // get info
176     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
177     hci_connection_t *conn      = connection_for_handle(con_handle);
178     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
179     uint16_t acl_length         = READ_ACL_LENGTH(packet);
180 
181     // ignore non-registered handle
182     if (!conn){
183         log_err( "hci.c: acl_handler called with non-registered handle %u!\n" , con_handle);
184         return;
185     }
186 
187     // update idle timestamp
188     hci_connection_timestamp(conn);
189 
190     // handle different packet types
191     switch (acl_flags & 0x03) {
192 
193         case 0x01: // continuation fragment
194 
195             // sanity check
196             if (conn->acl_recombination_pos == 0) {
197                 log_err( "ACL Cont Fragment but no first fragment for handle 0x%02x\n", con_handle);
198                 return;
199             }
200 
201             // append fragment payload (header already stored)
202             memcpy(&conn->acl_recombination_buffer[conn->acl_recombination_pos], &packet[4], acl_length );
203             conn->acl_recombination_pos += acl_length;
204 
205             // log_err( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u\n",
206             //        acl_length, connection->acl_recombination_pos, connection->acl_recombination_length);
207 
208             // forward complete L2CAP packet if complete.
209             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
210 
211                 hci_stack.acl_packet_handler(conn->acl_recombination_buffer, conn->acl_recombination_pos);
212                 // reset recombination buffer
213                 conn->acl_recombination_length = 0;
214                 conn->acl_recombination_pos = 0;
215             }
216             break;
217 
218         case 0x02: { // first fragment
219 
220             // sanity check
221             if (conn->acl_recombination_pos) {
222                 log_err( "ACL First Fragment but data in buffer for handle 0x%02x\n", con_handle);
223                 return;
224             }
225 
226             // peek into L2CAP packet!
227             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
228 
229             // compare fragment size to L2CAP packet size
230             if (acl_length >= l2cap_length + 4){
231 
232                 // forward fragment as L2CAP packet
233                 hci_stack.acl_packet_handler(packet, acl_length + 4);
234 
235             } else {
236                 // store first fragment and tweak acl length for complete package
237                 memcpy(conn->acl_recombination_buffer, packet, acl_length + 4);
238                 conn->acl_recombination_pos    = acl_length + 4;
239                 conn->acl_recombination_length = l2cap_length;
240                 bt_store_16(conn->acl_recombination_buffer, 2, acl_length +4);
241                 // log_err( "ACL First Fragment: acl_len %u, l2cap_len %u\n", acl_length, l2cap_length);
242             }
243             break;
244 
245         }
246         default:
247             log_err( "hci.c: acl_handler called with invalid packet boundary flags %u\n", acl_flags & 0x03);
248             return;
249     }
250 
251     // execute main loop
252     hci_run();
253 }
254 
255 static void event_handler(uint8_t *packet, int size){
256     bd_addr_t addr;
257     hci_con_handle_t handle;
258     hci_connection_t * conn;
259 
260     switch (packet[0]) {
261 
262         case HCI_EVENT_COMMAND_COMPLETE:
263         case HCI_EVENT_COMMAND_STATUS:
264             // Get Num_HCI_Command_Packets
265             hci_stack.num_cmd_packets = packet[2];
266             break;
267 
268         case HCI_EVENT_CONNECTION_REQUEST:
269             bt_flip_addr(addr, &packet[2]);
270             // TODO: eval COD 8-10
271             uint8_t link_type = packet[11];
272             log_dbg("Connection_incoming: "); print_bd_addr(addr); log_dbg(", type %u\n", link_type);
273             if (link_type == 1) { // ACL
274                 conn = connection_for_address(addr);
275                 if (!conn) {
276                     conn = create_connection_for_addr(addr);
277                 }
278                 // TODO: check for malloc failure
279                 conn->state = ACCEPTED_CONNECTION_REQUEST;
280                 hci_send_cmd(&hci_accept_connection_request, addr, 1);
281             } else {
282                 // TODO: decline request
283             }
284             break;
285 
286         case HCI_EVENT_CONNECTION_COMPLETE:
287             // Connection management
288             bt_flip_addr(addr, &packet[5]);
289             log_dbg("Connection_complete (status=%u)", packet[2]); print_bd_addr(addr); log_dbg("\n");
290             conn = connection_for_address(addr);
291             if (conn) {
292                 if (!packet[2]){
293                     conn->state = OPEN;
294                     conn->con_handle = READ_BT_16(packet, 3);
295                     conn->flags = 0;
296 
297                     gettimeofday(&conn->timestamp, NULL);
298                     run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
299                     run_loop_add_timer(&conn->timeout);
300 
301                     log_dbg("New connection: handle %u, ", conn->con_handle);
302                     print_bd_addr( conn->address );
303                     log_dbg("\n");
304 
305                     hci_emit_nr_connections_changed();
306                 } else {
307                     // connection failed, remove entry
308                     linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
309                     free( conn );
310                 }
311             }
312             break;
313 
314         case HCI_EVENT_DISCONNECTION_COMPLETE:
315             if (!packet[2]){
316                 handle = READ_BT_16(packet, 3);
317                 hci_connection_t * conn = connection_for_handle(handle);
318                 if (conn) {
319                     log_dbg("Connection closed: handle %u, ", conn->con_handle);
320                     print_bd_addr( conn->address );
321                     log_dbg("\n");
322                     run_loop_remove_timer(&conn->timeout);
323                     linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
324                     free( conn );
325                     hci_emit_nr_connections_changed();
326                 }
327             }
328             break;
329 
330         default:
331             break;
332     }
333 
334     // handle BT initialization
335     if (hci_stack.state == HCI_STATE_INITIALIZING){
336         // handle H4 synchronization loss on restart
337         // if (hci_stack.substate == 1 && packet[0] == HCI_EVENT_HARDWARE_ERROR){
338         //    hci_stack.substate = 0;
339         // }
340         // handle normal init sequence
341         if (hci_stack.substate % 2){
342             // odd: waiting for event
343             if (packet[0] == HCI_EVENT_COMMAND_COMPLETE){
344                 hci_stack.substate++;
345             }
346         }
347     }
348 
349     hci_stack.event_packet_handler(packet, size);
350 
351 	// execute main loop
352 	hci_run();
353 }
354 
355 void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
356     switch (packet_type) {
357         case HCI_EVENT_PACKET:
358             event_handler(packet, size);
359             break;
360         case HCI_ACL_DATA_PACKET:
361             acl_handler(packet, size);
362             break;
363         default:
364             break;
365     }
366 }
367 
368 /** Register HCI packet handlers */
369 void hci_register_event_packet_handler(void (*handler)(uint8_t *packet, uint16_t size)){
370     hci_stack.event_packet_handler = handler;
371 }
372 void hci_register_acl_packet_handler  (void (*handler)(uint8_t *packet, uint16_t size)){
373     hci_stack.acl_packet_handler = handler;
374 }
375 
376 void hci_init(hci_transport_t *transport, void *config, bt_control_t *control){
377 
378     // reference to use transport layer implementation
379     hci_stack.hci_transport = transport;
380 
381     // references to used control implementation
382     if (control) {
383         hci_stack.control = control;
384     } else {
385         hci_stack.control = &null_control;
386     }
387 
388     // reference to used config
389     hci_stack.config = config;
390 
391     // no connections yet
392     hci_stack.connections = NULL;
393 
394     // empty cmd buffer
395     hci_stack.hci_cmd_buffer = malloc(3+255);
396 
397     // higher level handler
398     hci_stack.event_packet_handler = dummy_handler;
399     hci_stack.acl_packet_handler = dummy_handler;
400 
401     // register packet handlers with transport
402     transport->register_packet_handler(&packet_handler);
403 }
404 
405 int hci_power_control(HCI_POWER_MODE power_mode){
406     if (power_mode == HCI_POWER_ON && hci_stack.state == HCI_STATE_OFF) {
407 
408         // power on
409         int err = hci_stack.control->on(hci_stack.config);
410         if (err){
411             log_err( "POWER_ON failed\n");
412             hci_emit_hci_open_failed();
413             return err;
414         }
415 
416         // open low-level device
417         err = hci_stack.hci_transport->open(hci_stack.config);
418         if (err){
419             log_err( "HCI_INIT failed, turning Bluetooth off again\n");
420             hci_stack.control->off(hci_stack.config);
421             hci_emit_hci_open_failed();
422             return err;
423         }
424 
425         // set up state machine
426         hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
427         hci_stack.state = HCI_STATE_INITIALIZING;
428         hci_stack.substate = 0;
429 
430     } else if (power_mode == HCI_POWER_OFF && hci_stack.state == HCI_STATE_WORKING){
431 
432         // close low-level device
433         hci_stack.hci_transport->close(hci_stack.config);
434 
435         // power off
436         hci_stack.control->off(hci_stack.config);
437 
438         // we're off now
439         hci_stack.state = HCI_STATE_OFF;
440     }
441 
442     // create internal event
443 	hci_emit_state();
444 
445 	// trigger next/first action
446 	hci_run();
447 
448     return 0;
449 }
450 
451 void hci_run(){
452     switch (hci_stack.state){
453         case HCI_STATE_INITIALIZING:
454             if (hci_stack.substate % 2) {
455                 // odd: waiting for command completion
456                 return;
457             }
458             if (hci_stack.num_cmd_packets == 0) {
459                 // cannot send command yet
460                 return;
461             }
462             switch (hci_stack.substate/2){
463                 case 0:
464                     hci_send_cmd(&hci_reset);
465                     break;
466 				case 1:
467 					hci_send_cmd(&hci_read_bd_addr);
468 					break;
469                 case 2:
470                     // ca. 15 sec
471                     hci_send_cmd(&hci_write_page_timeout, 0x6000);
472                     break;
473 				case 3:
474 					hci_send_cmd(&hci_write_scan_enable, 3); // 3 inq scan + page scan
475 					break;
476                 case 4:
477                     // done.
478                     hci_stack.state = HCI_STATE_WORKING;
479                     hci_emit_state();
480                     break;
481                 default:
482                     break;
483             }
484             hci_stack.substate++;
485             break;
486         default:
487             break;
488     }
489 }
490 
491 int hci_send_cmd_packet(uint8_t *packet, int size){
492     bd_addr_t addr;
493     hci_connection_t * conn;
494     // house-keeping
495 
496     // create_connection?
497     if (IS_COMMAND(packet, hci_create_connection)){
498         bt_flip_addr(addr, &packet[3]);
499         log_dbg("Create_connection to "); print_bd_addr(addr); log_dbg("\n");
500         conn = connection_for_address(addr);
501         if (conn) {
502             // if connection exists
503             if (conn->state == OPEN) {
504                 // if OPEN, emit connection complete command
505                 hci_emit_connection_complete(conn);
506             }
507             //    otherwise, just ignore
508             return 0; // don't sent packet to controller
509 
510         } else{
511             conn = create_connection_for_addr(addr);
512             if (conn){
513                 //    create connection struct and register, state = SENT_CREATE_CONNECTION
514                 conn->state = SENT_CREATE_CONNECTION;
515             }
516         }
517     }
518 
519     // accept connection
520 
521     // reject connection
522 
523     // close_connection?
524       // set state = SENT_DISCONNECT
525 
526     hci_stack.num_cmd_packets--;
527     return hci_stack.hci_transport->send_cmd_packet(packet, size);
528 }
529 
530 /**
531  * pre: numcmds >= 0 - it's allowed to send a command to the controller
532  */
533 int hci_send_cmd(hci_cmd_t *cmd, ...){
534     va_list argptr;
535     va_start(argptr, cmd);
536     uint8_t * hci_cmd_buffer = hci_stack.hci_cmd_buffer;
537     uint16_t size = hci_create_cmd_internal(hci_stack.hci_cmd_buffer, cmd, argptr);
538     va_end(argptr);
539     return hci_send_cmd_packet(hci_cmd_buffer, size);
540 }
541 
542 // Create various non-HCI events.
543 // TODO: generalize, use table similar to hci_create_command
544 
545 void hci_emit_state(){
546     uint8_t len = 3;
547     uint8_t event[len];
548     event[0] = BTSTACK_EVENT_STATE;
549     event[1] = len - 3;
550     event[2] = hci_stack.state;
551     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
552     hci_stack.event_packet_handler(event, len);
553 }
554 
555 void hci_emit_connection_complete(hci_connection_t *conn){
556     uint8_t len = 13;
557     uint8_t event[len];
558     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
559     event[1] = len - 3;
560     event[2] = 0; // status = OK
561     bt_store_16(event, 3, conn->con_handle);
562     bt_flip_addr(&event[5], conn->address);
563     event[11] = 1; // ACL connection
564     event[12] = 0; // encryption disabled
565     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
566     hci_stack.event_packet_handler(event, len);
567 }
568 
569 void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
570     uint8_t len = 4;
571     uint8_t event[len];
572     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
573     event[1] = len - 2;
574     bt_store_16(event, 2, conn->con_handle);
575     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
576     hci_stack.event_packet_handler(event, len);
577 }
578 
579 void hci_emit_nr_connections_changed(){
580     uint8_t len = 3;
581     uint8_t event[len];
582     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
583     event[1] = len - 2;
584     event[2] = nr_hci_connections();
585     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
586     hci_stack.event_packet_handler(event, len);
587 }
588 
589 void hci_emit_hci_open_failed(){
590     uint8_t len = 2;
591     uint8_t event[len];
592     event[0] = BTSTACK_EVENT_POWERON_FAILED;
593     event[1] = len - 2;
594     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
595     hci_stack.event_packet_handler(event, len);
596 }
597 
598 
599 void hci_emit_btstack_version() {
600     uint8_t len = 6;
601     uint8_t event[len];
602     event[0] = BTSTACK_EVENT_VERSION;
603     event[1] = len - 2;
604     event[len++] = BTSTACK_MAJOR;
605     event[len++] = BTSTACK_MINOR;
606     bt_store_16(event, len, BTSTACK_REVISION);
607     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
608     hci_stack.event_packet_handler(event, len);
609 }
610 
611 void hci_emit_system_bluetooth_enabled(uint8_t enabled){
612     uint8_t len = 3;
613     uint8_t event[len];
614     event[0] = BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED;
615     event[1] = len - 2;
616     event[2] = enabled;
617     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
618     hci_stack.event_packet_handler(event, len);
619 }
620