xref: /btstack/example/panu_demo.c (revision f9f2075ceac5e9dc08e9abea437e43d733a3a0ea)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
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15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
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19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
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36  */
37 
38 /*
39  * panu_demo.c
40  * Author: Ole Reinhardt <[email protected]>
41  */
42 
43 /* EXAMPLE_START(panu_demo): PANU Demo
44  *
45  * @text This example implements both a PANU client and a server. In server mode, it
46  * sets up a BNEP server and registers a PANU SDP record and waits for incoming connections.
47  * In client mode, it connects to a remote device, does an SDP Query to identify the PANU
48  * service and initiates a BNEP connection.
49  */
50 
51 #include "btstack_config.h"
52 
53 #include <arpa/inet.h>
54 #include <errno.h>
55 #include <fcntl.h>
56 #include <ifaddrs.h>
57 #include <stdint.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include <unistd.h>
62 
63 #include <net/if_arp.h>
64 
65 #ifdef __APPLE__
66 #include <net/if.h>
67 #include <net/if_types.h>
68 
69 #include <netinet/if_ether.h>
70 #include <netinet/in.h>
71 #endif
72 
73 #include <sys/ioctl.h>
74 #include <sys/param.h>
75 #include <sys/socket.h>
76 #include <sys/stat.h>
77 #include <sys/types.h>
78 
79 #ifdef __linux
80 #include <linux/if.h>
81 #include <linux/if_tun.h>
82 #endif
83 
84 #include "btstack_memory.h"
85 #include "btstack_event.h"
86 #include "btstack_run_loop.h"
87 #include "classic/sdp_client.h"
88 #include "classic/sdp_util.h"
89 #include "hci.h"
90 #include "hci_cmd.h"
91 #include "hci_dump.h"
92 #include "l2cap.h"
93 #include "pan.h"
94 
95 static int record_id = -1;
96 static uint16_t bnep_l2cap_psm      = 0;
97 static uint32_t bnep_remote_uuid    = 0;
98 static uint16_t bnep_version        = 0;
99 static uint16_t bnep_cid            = 0;
100 
101 static uint8_t   attribute_value[1000];
102 static const unsigned int attribute_value_buffer_size = sizeof(attribute_value);
103 
104 //static bd_addr_t remote = {0x04,0x0C,0xCE,0xE4,0x85,0xD3};
105 // static bd_addr_t remote = {0xE0,0x06,0xE6,0xBB,0x95,0x79}; // Ole Thinkpad
106 static bd_addr_t remote = {0x84,0x38,0x35,0x65,0xD1,0x15};  // MacBook 2013
107 
108 static int  tap_fd = -1;
109 static uint8_t network_buffer[BNEP_MTU_MIN];
110 static size_t  network_buffer_len = 0;
111 
112 #ifdef __APPLE__
113 // tuntaposx provides fixed set of tapX devices
114 static const char * tap_dev = "/dev/tap0";
115 static char tap_dev_name[16] = "tap0";
116 #endif
117 
118 #ifdef __linux
119 // Linux uses single control device to bring up tunX or tapX interface
120 static const char * tap_dev = "/dev/net/tun";
121 static char tap_dev_name[16] = "bnep%d";
122 #endif
123 
124 
125 static btstack_data_source_t tap_dev_ds;
126 static btstack_packet_callback_registration_t hci_event_callback_registration;
127 
128 /* @section Main application configuration
129  *
130  * @text In the application configuration, L2CAP and BNEP are initialized and a BNEP service, for server mode,
131  * is registered, before the Bluetooth stack gets started, as shown in Listing PanuSetup.
132  */
133 
134 /* LISTING_START(PanuSetup): Panu setup */
135 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
136 static void handle_sdp_client_query_result(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
137 
138 static void panu_setup(void){
139 
140     // register for HCI events
141     hci_event_callback_registration.callback = &packet_handler;
142     hci_add_event_handler(&hci_event_callback_registration);
143 
144     // Initialize L2CAP
145     l2cap_init();
146 
147     // Initialise BNEP
148     bnep_init();
149     // Minimum L2CAP MTU for bnep is 1691 bytes
150     bnep_register_service(packet_handler, SDP_PANU, 1691);
151 }
152 /* LISTING_END */
153 
154 /* @section TUN / TAP interface routines
155  *
156  * @text This example requires a TUN/TAP interface to connect the Bluetooth network interface
157  * with the native system. It has been tested on Linux and OS X, but should work on any
158  * system that provides TUN/TAP with minor modifications.
159  *
160  * On Linux, TUN/TAP is available by default. On OS X, tuntaposx from
161  * http://tuntaposx.sourceforge.net needs to be installed.
162  *
163  * The *tap_alloc* function sets up a virtual network interface with the given Bluetooth Address.
164  * It is rather low-level as it sets up and configures a network interface.
165  */
166 
167 static int tap_alloc(char *dev, bd_addr_t bd_addr)
168 {
169     struct ifreq ifr;
170     int fd_dev;
171     int fd_socket;
172 
173     if( (fd_dev = open(tap_dev, O_RDWR)) < 0 ) {
174         fprintf(stderr, "TAP: Error opening %s: %s\n", tap_dev, strerror(errno));
175         return -1;
176     }
177 
178 #ifdef __linux
179     memset(&ifr, 0, sizeof(ifr));
180 
181     ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
182     if( *dev ) {
183         strncpy(ifr.ifr_name, dev, IFNAMSIZ);
184     }
185 
186     int err;
187     if( (err = ioctl(fd_dev, TUNSETIFF, (void *) &ifr)) < 0 ) {
188         fprintf(stderr, "TAP: Error setting device name: %s\n", strerror(errno));
189         close(fd_dev);
190         return -1;
191     }
192     strcpy(dev, ifr.ifr_name);
193 #endif
194 #ifdef __APPLE__
195     dev = tap_dev_name;
196 #endif
197 
198     fd_socket = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
199 	if (fd_socket < 0) {
200         close(fd_dev);
201 		fprintf(stderr, "TAP: Error opening netlink socket: %s\n", strerror(errno));
202 		return -1;
203 	}
204 
205     // Configure the MAC address of the newly created bnep(x)
206     // device to the local bd_address
207     memset (&ifr, 0, sizeof(struct ifreq));
208     strcpy(ifr.ifr_name, dev);
209 #ifdef __linux
210     ifr.ifr_hwaddr.sa_family = ARPHRD_ETHER;
211     memcpy(ifr.ifr_hwaddr.sa_data, bd_addr, sizeof(bd_addr_t));
212 	if (ioctl(fd_socket, SIOCSIFHWADDR, &ifr) == -1) {
213         close(fd_dev);
214         close(fd_socket);
215         fprintf(stderr, "TAP: Error setting hw addr: %s\n", strerror(errno));
216         exit(1);
217 		return -1;
218 	}
219 #endif
220 #ifdef __APPLE__
221     ifr.ifr_addr.sa_len = ETHER_ADDR_LEN;
222     ifr.ifr_addr.sa_family = AF_LINK;
223     (void)memcpy(ifr.ifr_addr.sa_data, bd_addr, ETHER_ADDR_LEN);
224     if (ioctl(fd_socket, SIOCSIFLLADDR, &ifr) == -1) {
225         close(fd_dev);
226         close(fd_socket);
227         fprintf(stderr, "TAP: Error setting hw addr: %s\n", strerror(errno));
228         exit(1);
229         return -1;
230 }
231 #endif
232 
233     // Bring the interface up
234 	if (ioctl(fd_socket, SIOCGIFFLAGS, &ifr) == -1) {
235         close(fd_dev);
236         close(fd_socket);
237 		fprintf(stderr, "TAP: Error reading interface flags: %s\n", strerror(errno));
238 		return -1;
239 	}
240 
241 	if ((ifr.ifr_flags & IFF_UP) == 0) {
242 		ifr.ifr_flags |= IFF_UP;
243 
244 		if (ioctl(fd_socket, SIOCSIFFLAGS, &ifr) == -1) {
245             close(fd_dev);
246             close(fd_socket);
247             fprintf(stderr, "TAP: Error set IFF_UP: %s\n", strerror(errno));
248             return -1;
249 		}
250 	}
251 
252 	close(fd_socket);
253 
254     return fd_dev;
255 }
256 
257 /*
258  * @text Listing processTapData shows how a packet is received from the TAP network interface
259  * and forwarded over the BNEP connection.
260  *
261  * After successfully reading a network packet, the call to
262  * the *bnep_can_send_packet_now* function checks, if BTstack can forward
263  * a network packet now. If that's not possible, the received data stays
264  * in the network buffer and the data source elements is removed from the
265  * run loop. The *process_tap_dev_data* function will not be called until
266  * the data source is registered again. This provides a basic flow control.
267  */
268 
269 /* LISTING_START(processTapData): Process incoming network packets */
270 static void process_tap_dev_data(btstack_data_source_t *ds, btstack_data_source_callback_type_t callback_type)
271 {
272     UNUSED(ds);
273     UNUSED(callback_type);
274 
275     ssize_t len;
276     len = read(ds->fd, network_buffer, sizeof(network_buffer));
277     if (len <= 0){
278         fprintf(stderr, "TAP: Error while reading: %s\n", strerror(errno));
279         return;
280     }
281 
282     network_buffer_len = len;
283     if (bnep_can_send_packet_now(bnep_cid)) {
284         bnep_send(bnep_cid, network_buffer, network_buffer_len);
285         network_buffer_len = 0;
286     } else {
287         // park the current network packet
288         btstack_run_loop_remove_data_source(&tap_dev_ds);
289     }
290     return;
291 }
292 /* LISTING_END */
293 
294 // PANU client routines
295 static char * get_string_from_data_element(uint8_t * element){
296     de_size_t de_size = de_get_size_type(element);
297     int pos     = de_get_header_size(element);
298     int len = 0;
299     switch (de_size){
300         case DE_SIZE_VAR_8:
301             len = element[1];
302             break;
303         case DE_SIZE_VAR_16:
304             len = big_endian_read_16(element, 1);
305             break;
306         default:
307             break;
308     }
309     char * str = (char*)malloc(len+1);
310     memcpy(str, &element[pos], len);
311     str[len] ='\0';
312     return str;
313 }
314 
315 
316 /* @section SDP parser callback
317  *
318  * @text The SDP parsers retrieves the BNEP PAN UUID as explained in
319  * Section [on SDP BNEP Query example](#sec:sdpbnepqueryExample}.
320  */
321 static void handle_sdp_client_query_result(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size) {
322 
323     UNUSED(packet_type);
324     UNUSED(channel);
325     UNUSED(size);
326 
327     des_iterator_t des_list_it;
328     des_iterator_t prot_it;
329     char *str;
330 
331     switch (hci_event_packet_get_type(packet)){
332         case SDP_EVENT_QUERY_ATTRIBUTE_VALUE:
333             // Handle new SDP record
334             if (sdp_event_query_attribute_byte_get_record_id(packet) != record_id) {
335                 record_id = sdp_event_query_attribute_byte_get_record_id(packet);
336                 printf("SDP Record: Nr: %d\n", record_id);
337             }
338 
339             if (sdp_event_query_attribute_byte_get_attribute_length(packet) <= attribute_value_buffer_size) {
340                 attribute_value[sdp_event_query_attribute_byte_get_data_offset(packet)] = sdp_event_query_attribute_byte_get_data(packet);
341 
342                 if ((uint16_t)(sdp_event_query_attribute_byte_get_data_offset(packet)+1) == sdp_event_query_attribute_byte_get_attribute_length(packet)) {
343 
344                     switch(sdp_event_query_attribute_byte_get_attribute_id(packet)) {
345                         case SDP_ServiceClassIDList:
346                             if (de_get_element_type(attribute_value) != DE_DES) break;
347                             for (des_iterator_init(&des_list_it, attribute_value); des_iterator_has_more(&des_list_it); des_iterator_next(&des_list_it)) {
348                                 uint8_t * element = des_iterator_get_element(&des_list_it);
349                                 if (de_get_element_type(element) != DE_UUID) continue;
350                                 uint32_t uuid = de_get_uuid32(element);
351                                 switch (uuid){
352                                     case SDP_PANU:
353                                     case SDP_NAP:
354                                     case SDP_GN:
355                                         printf("SDP Attribute 0x%04x: BNEP PAN protocol UUID: %04x\n", sdp_event_query_attribute_byte_get_attribute_id(packet), uuid);
356                                         bnep_remote_uuid = uuid;
357                                         break;
358                                     default:
359                                         break;
360                                 }
361                             }
362                             break;
363                         case 0x0100:
364                         case 0x0101:
365                             str = get_string_from_data_element(attribute_value);
366                             printf("SDP Attribute: 0x%04x: %s\n", sdp_event_query_attribute_byte_get_attribute_id(packet), str);
367                             free(str);
368                             break;
369                         case 0x0004: {
370                                 printf("SDP Attribute: 0x%04x\n", sdp_event_query_attribute_byte_get_attribute_id(packet));
371 
372                                 for (des_iterator_init(&des_list_it, attribute_value); des_iterator_has_more(&des_list_it); des_iterator_next(&des_list_it)) {
373                                     uint8_t       *des_element;
374                                     uint8_t       *element;
375                                     uint32_t       uuid;
376 
377                                     if (des_iterator_get_type(&des_list_it) != DE_DES) continue;
378 
379                                     des_element = des_iterator_get_element(&des_list_it);
380                                     des_iterator_init(&prot_it, des_element);
381                                     element = des_iterator_get_element(&prot_it);
382 
383                                     if (de_get_element_type(element) != DE_UUID) continue;
384 
385                                     uuid = de_get_uuid32(element);
386                                     switch (uuid){
387                                         case SDP_L2CAPProtocol:
388                                             if (!des_iterator_has_more(&prot_it)) continue;
389                                             des_iterator_next(&prot_it);
390                                             de_element_get_uint16(des_iterator_get_element(&prot_it), &bnep_l2cap_psm);
391                                             break;
392                                         case SDP_BNEPProtocol:
393                                             if (!des_iterator_has_more(&prot_it)) continue;
394                                             des_iterator_next(&prot_it);
395                                             de_element_get_uint16(des_iterator_get_element(&prot_it), &bnep_version);
396                                             break;
397                                         default:
398                                             break;
399                                     }
400                                 }
401                                 printf("l2cap_psm 0x%04x, bnep_version 0x%04x\n", bnep_l2cap_psm, bnep_version);
402 
403                                 /* Create BNEP connection */
404                                 bnep_connect(packet_handler, remote, bnep_l2cap_psm, PANU_UUID, bnep_remote_uuid);
405                             }
406                             break;
407                         default:
408                             break;
409                     }
410                 }
411             } else {
412                 fprintf(stderr, "SDP attribute value buffer size exceeded: available %d, required %d\n", attribute_value_buffer_size, sdp_event_query_attribute_byte_get_attribute_length(packet));
413             }
414             break;
415 
416         case SDP_EVENT_QUERY_COMPLETE:
417             fprintf(stderr, "General query done with status %d.\n", sdp_event_query_complete_get_status(packet));
418 
419             break;
420     }
421 }
422 
423 /*
424  * @section Packet Handler
425  *
426  * @text The packet handler responds to various HCI Events.
427  */
428 
429 
430 /* LISTING_START(packetHandler): Packet Handler */
431 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size)
432 {
433 /* LISTING_PAUSE */
434     UNUSED(channel);
435 
436     int       rc;
437     uint8_t   event;
438     bd_addr_t event_addr;
439     bd_addr_t local_addr;
440     uint16_t  uuid_source;
441     uint16_t  uuid_dest;
442     uint16_t  mtu;
443 
444     /* LISTING_RESUME */
445     switch (packet_type) {
446 		case HCI_EVENT_PACKET:
447             event = hci_event_packet_get_type(packet);
448             switch (event) {
449                 /* @text When BTSTACK_EVENT_STATE with state HCI_STATE_WORKING
450                  * is received and the example is started in client mode, the remote SDP BNEP query is started.
451                  */
452                 case BTSTACK_EVENT_STATE:
453                     if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING){
454                         printf("Start SDP BNEP query.\n");
455                         sdp_client_query_uuid16(&handle_sdp_client_query_result, remote, SDP_BNEPProtocol);
456                     }
457                     break;
458 
459                 /* LISTING_PAUSE */
460                 case HCI_EVENT_PIN_CODE_REQUEST:
461 					// inform about pin code request
462                     printf("Pin code request - using '0000'\n");
463                     hci_event_pin_code_request_get_bd_addr(packet, event_addr);
464 					hci_send_cmd(&hci_pin_code_request_reply, &event_addr, 4, "0000");
465 					break;
466 
467                 case HCI_EVENT_USER_CONFIRMATION_REQUEST:
468                     // inform about user confirmation request
469                     printf("SSP User Confirmation Request with numeric value '%06u'\n", little_endian_read_32(packet, 8));
470                     printf("SSP User Confirmation Auto accept\n");
471                     break;
472 
473                 /* LISTING_RESUME */
474 
475                 /* @text BNEP_EVENT_CHANNEL_OPENED is received after a BNEP connection was established or
476                  * or when the connection fails. The status field returns the error code.
477                  *
478                  * The TAP network interface is then configured. A data source is set up and registered with the
479                  * run loop to receive Ethernet packets from the TAP interface.
480                  *
481                  * The event contains both the source and destination UUIDs, as well as the MTU for this connection and
482                  * the BNEP Channel ID, which is used for sending Ethernet packets over BNEP.
483                  */
484 				case BNEP_EVENT_CHANNEL_OPENED:
485                     if (bnep_event_channel_opened_get_status(packet)) {
486                         printf("BNEP channel open failed, status %02x\n", bnep_event_channel_opened_get_status(packet));
487                     } else {
488                         bnep_cid    = bnep_event_channel_opened_get_bnep_cid(packet);
489                         uuid_source = bnep_event_channel_opened_get_source_uuid(packet);
490                         uuid_dest   = bnep_event_channel_opened_get_destination_uuid(packet);
491                         mtu         = bnep_event_channel_opened_get_mtu(packet);
492                         //bt_flip_addr(event_addr, &packet[9]);
493                         memcpy(&event_addr, &packet[11], sizeof(bd_addr_t));
494                         printf("BNEP connection open succeeded to %s source UUID 0x%04x dest UUID: 0x%04x, max frame size %u\n", bd_addr_to_str(event_addr), uuid_source, uuid_dest, mtu);
495                         /* Create the tap interface */
496                         gap_local_bd_addr(local_addr);
497                         tap_fd = tap_alloc(tap_dev_name, local_addr);
498                         if (tap_fd < 0) {
499                             printf("Creating BNEP tap device failed: %s\n", strerror(errno));
500                         } else {
501                             printf("BNEP device \"%s\" allocated.\n", tap_dev_name);
502                             /* Create and register a new runloop data source */
503                             btstack_run_loop_set_data_source_fd(&tap_dev_ds, tap_fd);
504                             btstack_run_loop_set_data_source_handler(&tap_dev_ds, &process_tap_dev_data);
505                             btstack_run_loop_add_data_source(&tap_dev_ds);
506                         }
507                     }
508 					break;
509 
510                 /* @text If there is a timeout during the connection setup, BNEP_EVENT_CHANNEL_TIMEOUT will be received
511                  * and the BNEP connection  will be closed
512                  */
513                 case BNEP_EVENT_CHANNEL_TIMEOUT:
514                     printf("BNEP channel timeout! Channel will be closed\n");
515                     break;
516 
517                 /* @text BNEP_EVENT_CHANNEL_CLOSED is received when the connection gets closed.
518                  */
519                 case BNEP_EVENT_CHANNEL_CLOSED:
520                     printf("BNEP channel closed\n");
521                     btstack_run_loop_remove_data_source(&tap_dev_ds);
522                     if (tap_fd > 0) {
523                         close(tap_fd);
524                         tap_fd = -1;
525                     }
526                     break;
527 
528                 /* @text BNEP_EVENT_CAN_SEND_NOW indicates that a new packet can be send. This triggers the retry of a
529                  * parked network packet. If this succeeds, the data source element is added to the run loop again.
530                  */
531                 case BNEP_EVENT_CAN_SEND_NOW:
532                     // Check for parked network packets and send it out now
533                     if (network_buffer_len > 0) {
534                         bnep_send(bnep_cid, network_buffer, network_buffer_len);
535                         network_buffer_len = 0;
536                         // Re-add the tap device data source
537                         btstack_run_loop_add_data_source(&tap_dev_ds);
538                     }
539 
540                     break;
541 
542                 default:
543                     break;
544             }
545             break;
546 
547         /* @text Ethernet packets from the remote device are received in the packet handler with type BNEP_DATA_PACKET.
548          * It is forwarded to the TAP interface.
549          */
550         case BNEP_DATA_PACKET:
551             // Write out the ethernet frame to the tap device
552             if (tap_fd > 0) {
553                 rc = write(tap_fd, packet, size);
554                 if (rc < 0) {
555                     fprintf(stderr, "TAP: Could not write to TAP device: %s\n", strerror(errno));
556                 } else
557                 if (rc != size) {
558                     fprintf(stderr, "TAP: Package written only partially %d of %d bytes\n", rc, size);
559                 }
560             }
561             break;
562 
563         default:
564             break;
565     }
566 }
567 /* LISTING_END */
568 
569 
570 int btstack_main(int argc, const char * argv[]);
571 int btstack_main(int argc, const char * argv[]){
572 
573     UNUSED(argc);
574     UNUSED(argv);
575 
576     printf("Client HCI init done\n");
577 
578     panu_setup();
579     // Turn on the device
580     hci_power_control(HCI_POWER_ON);
581     return 0;
582 }
583 
584 /* EXAMPLE_END */
585 /* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 4; tab-width: 4 -*-  */
586 
587