xref: /freebsd/usr.sbin/bluetooth/sdpd/server.c (revision f0adf7f5cdd241db2f2c817683191a6ef64a4e95)
1 /*
2  * server.c
3  *
4  * Copyright (c) 2004 Maksim Yevmenkin <m_evmenkin@yahoo.com>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $Id: server.c,v 1.6 2004/01/13 01:54:39 max Exp $
29  * $FreeBSD$
30  */
31 
32 #include <sys/select.h>
33 #include <sys/queue.h>
34 #include <sys/un.h>
35 #include <netinet/in.h>
36 #include <arpa/inet.h>
37 #include <assert.h>
38 #include <bluetooth.h>
39 #include <errno.h>
40 #include <sdp.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 #include "log.h"
46 #include "profile.h"
47 #include "provider.h"
48 #include "server.h"
49 
50 static void	server_accept_client		(server_p srv, int32_t fd);
51 static int32_t	server_process_request		(server_p srv, int32_t fd);
52 static int32_t	server_send_error_response	(server_p srv, int32_t fd,
53 						 uint16_t error);
54 static void	server_close_fd			(server_p srv, int32_t fd);
55 
56 /*
57  * Initialize server
58  */
59 
60 int32_t
61 server_init(server_p srv, char const *control)
62 {
63 	struct sockaddr_un	un;
64 	struct sockaddr_l2cap	l2;
65 	int32_t			unsock, l2sock, size;
66 	uint16_t		imtu;
67 
68 	assert(srv != NULL);
69 	assert(control != NULL);
70 
71 	memset(srv, 0, sizeof(srv));
72 
73 	/* Open control socket */
74 	if (unlink(control) < 0 && errno != ENOENT) {
75 		log_crit("Could not unlink(%s). %s (%d)",
76 			control, strerror(errno), errno);
77 		return (-1);
78 	}
79 
80 	unsock = socket(PF_LOCAL, SOCK_STREAM, 0);
81 	if (unsock < 0) {
82 		log_crit("Could not create control socket. %s (%d)",
83 			strerror(errno), errno);
84 		return (-1);
85 	}
86 
87 	memset(&un, 0, sizeof(un));
88 	un.sun_len = sizeof(un);
89 	un.sun_family = AF_LOCAL;
90 	strlcpy(un.sun_path, control, sizeof(un.sun_path));
91 
92 	if (bind(unsock, (struct sockaddr *) &un, sizeof(un)) < 0) {
93 		log_crit("Could not bind control socket. %s (%d)",
94 			strerror(errno), errno);
95 		close(unsock);
96 		return (-1);
97 	}
98 
99 	if (listen(unsock, 10) < 0) {
100 		log_crit("Could not listen on control socket. %s (%d)",
101 			strerror(errno), errno);
102 		close(unsock);
103 		return (-1);
104 	}
105 
106 	/* Open L2CAP socket */
107 	l2sock = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BLUETOOTH_PROTO_L2CAP);
108 	if (l2sock < 0) {
109 		log_crit("Could not create L2CAP socket. %s (%d)",
110 			strerror(errno), errno);
111 		close(unsock);
112 		return (-1);
113 	}
114 
115 	size = sizeof(imtu);
116         if (getsockopt(l2sock, SOL_L2CAP, SO_L2CAP_IMTU, &imtu, &size) < 0) {
117 		log_crit("Could not get L2CAP IMTU. %s (%d)",
118 			strerror(errno), errno);
119 		close(unsock);
120 		close(l2sock);
121 		return (-1);
122         }
123 
124 	memset(&l2, 0, sizeof(l2));
125 	l2.l2cap_len = sizeof(l2);
126 	l2.l2cap_family = AF_BLUETOOTH;
127 	memcpy(&l2.l2cap_bdaddr, NG_HCI_BDADDR_ANY, sizeof(l2.l2cap_bdaddr));
128 	l2.l2cap_psm = NG_L2CAP_PSM_SDP;
129 
130 	if (bind(l2sock, (struct sockaddr *) &l2, sizeof(l2)) < 0) {
131 		log_crit("Could not bind L2CAP socket. %s (%d)",
132 			strerror(errno), errno);
133 		close(unsock);
134 		close(l2sock);
135 		return (-1);
136 	}
137 
138 	if (listen(l2sock, 10) < 0) {
139 		log_crit("Could not listen on L2CAP socket. %s (%d)",
140 			strerror(errno), errno);
141 		close(unsock);
142 		close(l2sock);
143 		return (-1);
144 	}
145 
146 	/* Allocate incoming buffer */
147 	srv->imtu = (imtu > SDP_LOCAL_MTU)? imtu : SDP_LOCAL_MTU;
148 	srv->req = (uint8_t *) calloc(srv->imtu, sizeof(srv->req[0]));
149 	if (srv->req == NULL) {
150 		log_crit("Could not allocate request buffer");
151 		close(unsock);
152 		close(l2sock);
153 		return (-1);
154 	}
155 
156 	/* Allocate memory for descriptor index */
157 	srv->fdidx = (fd_idx_p) calloc(FD_SETSIZE, sizeof(srv->fdidx[0]));
158 	if (srv->fdidx == NULL) {
159 		log_crit("Could not allocate fd index");
160 		free(srv->req);
161 		close(unsock);
162 		close(l2sock);
163 		return (-1);
164 	}
165 
166 	/* Register Service Discovery profile (attach it to control socket) */
167 	if (provider_register_sd(unsock) < 0) {
168 		log_crit("Could not register Service Discovery profile");
169 		free(srv->fdidx);
170 		free(srv->req);
171 		close(unsock);
172 		close(l2sock);
173 		return (-1);
174 	}
175 
176 	/*
177 	 * If we got here then everything is fine. Add both control sockets
178 	 * to the index.
179 	 */
180 
181 	FD_ZERO(&srv->fdset);
182 	srv->maxfd = (unsock > l2sock)? unsock : l2sock;
183 
184 	FD_SET(unsock, &srv->fdset);
185 	srv->fdidx[unsock].valid = 1;
186 	srv->fdidx[unsock].server = 1;
187 	srv->fdidx[unsock].control = 1;
188 	srv->fdidx[unsock].rsp_cs = 0;
189 	srv->fdidx[unsock].rsp_size = 0;
190 	srv->fdidx[unsock].rsp_limit = 0;
191 	srv->fdidx[unsock].omtu = SDP_LOCAL_MTU;
192 	srv->fdidx[unsock].rsp = NULL;
193 
194 	FD_SET(l2sock, &srv->fdset);
195 	srv->fdidx[l2sock].valid = 1;
196 	srv->fdidx[l2sock].server = 1;
197 	srv->fdidx[l2sock].control = 0;
198 	srv->fdidx[l2sock].rsp_cs = 0;
199 	srv->fdidx[l2sock].rsp_size = 0;
200 	srv->fdidx[l2sock].rsp_limit = 0;
201 	srv->fdidx[l2sock].omtu = 0; /* unknown */
202 	srv->fdidx[l2sock].rsp = NULL;
203 
204 	return (0);
205 }
206 
207 /*
208  * Shutdown server
209  */
210 
211 void
212 server_shutdown(server_p srv)
213 {
214 	int	fd;
215 
216 	assert(srv != NULL);
217 
218 	for (fd = 0; fd < srv->maxfd + 1; fd ++)
219 		if (srv->fdidx[fd].valid)
220 			server_close_fd(srv, fd);
221 
222 	free(srv->req);
223 	free(srv->fdidx);
224 
225 	memset(srv, 0, sizeof(*srv));
226 }
227 
228 /*
229  * Do one server iteration
230  */
231 
232 int32_t
233 server_do(server_p srv)
234 {
235 	fd_set	fdset;
236 	int32_t	n, fd;
237 
238 	assert(srv != NULL);
239 
240 	/* Copy cached version of the fd set and call select */
241 	memcpy(&fdset, &srv->fdset, sizeof(fdset));
242 	n = select(srv->maxfd + 1, &fdset, NULL, NULL, NULL);
243 	if (n < 0) {
244 		if (errno == EINTR)
245 			return (0);
246 
247 		log_err("Could not select(%d, %p). %s (%d)",
248 			srv->maxfd + 1, &fdset, strerror(errno), errno);
249 
250 		return (-1);
251 	}
252 
253 	/* Process  descriptors */
254 	for (fd = 0; fd < srv->maxfd + 1 && n > 0; fd ++) {
255 		if (!FD_ISSET(fd, &fdset))
256 			continue;
257 
258 		assert(srv->fdidx[fd].valid);
259 		n --;
260 
261 		if (srv->fdidx[fd].server)
262 			server_accept_client(srv, fd);
263 		else if (server_process_request(srv, fd) != 0)
264 			server_close_fd(srv, fd);
265 	}
266 
267 	return (0);
268 
269 }
270 
271 /*
272  * Accept new client connection and register it with index
273  */
274 
275 static void
276 server_accept_client(server_p srv, int32_t fd)
277 {
278 	uint8_t		*rsp = NULL;
279 	int32_t		 cfd, size;
280 	uint16_t	 omtu;
281 
282 	do {
283 		cfd = accept(fd, NULL, NULL);
284 	} while (cfd < 0 && errno == EINTR);
285 
286 	if (cfd < 0) {
287 		log_err("Could not accept connection on %s socket. %s (%d)",
288 			srv->fdidx[fd].control? "control" : "L2CAP",
289 			strerror(errno), errno);
290 		return;
291 	}
292 
293 	assert(!FD_ISSET(cfd, &srv->fdset));
294 	assert(!srv->fdidx[cfd].valid);
295 
296 	if (!srv->fdidx[fd].control) {
297 		/* Get local BD_ADDR */
298 		size = sizeof(srv->req_sa);
299 		if (getsockname(cfd,(struct sockaddr*)&srv->req_sa,&size) < 0) {
300 			log_err("Could not get local BD_ADDR. %s (%d)",
301 				strerror(errno), errno);
302 			close(cfd);
303 			return;
304 		}
305 
306 		/* Get outgoing MTU */
307 		size = sizeof(omtu);
308 	        if (getsockopt(cfd,SOL_L2CAP,SO_L2CAP_OMTU,&omtu,&size) < 0) {
309 			log_err("Could not get L2CAP OMTU. %s (%d)",
310 				strerror(errno), errno);
311 			close(cfd);
312 			return;
313 		}
314 
315 		/*
316 		 * The maximum size of the L2CAP packet is 65536 bytes.
317 		 * The minimum L2CAP MTU is 43 bytes. That means we need
318 		 * 65536 / 43 = ~1524 chunks to transfer maximum packet
319 		 * size with minimum MTU. The "rsp_cs" field in fd_idx_t
320 		 * is 11 bit wide that gives us upto 2048 chunks.
321 		 */
322 
323 		if (omtu < NG_L2CAP_MTU_MINIMUM) {
324 			log_err("L2CAP OMTU is too small (%d bytes)", omtu);
325 			close(cfd);
326 			return;
327 		}
328 	} else {
329 		memcpy(&srv->req_sa.l2cap_bdaddr, NG_HCI_BDADDR_ANY,
330 			sizeof(srv->req_sa.l2cap_bdaddr));
331 
332 		omtu = srv->fdidx[fd].omtu;
333 	}
334 
335 	/*
336 	 * Allocate buffer. This is an overkill, but we can not know how
337 	 * big our reply is going to be.
338 	 */
339 
340 	rsp = (uint8_t *) calloc(NG_L2CAP_MTU_MAXIMUM, sizeof(rsp[0]));
341 	if (rsp == NULL) {
342 		log_crit("Could not allocate response buffer");
343 		close(cfd);
344 		return;
345 	}
346 
347 	/* Add client descriptor to the index */
348 	FD_SET(cfd, &srv->fdset);
349 	if (srv->maxfd < cfd)
350 		srv->maxfd = cfd;
351 	srv->fdidx[cfd].valid = 1;
352 	srv->fdidx[cfd].server = 0;
353 	srv->fdidx[cfd].control = srv->fdidx[fd].control;
354 	srv->fdidx[cfd].rsp_cs = 0;
355 	srv->fdidx[cfd].rsp_size = 0;
356 	srv->fdidx[cfd].rsp_limit = 0;
357 	srv->fdidx[cfd].omtu = omtu;
358 	srv->fdidx[cfd].rsp = rsp;
359 }
360 
361 /*
362  * Process request from the client
363  */
364 
365 static int32_t
366 server_process_request(server_p srv, int32_t fd)
367 {
368 	sdp_pdu_p	pdu = (sdp_pdu_p) srv->req;
369 	int32_t		len, error;
370 
371 	assert(srv->imtu > 0);
372 	assert(srv->req != NULL);
373 	assert(FD_ISSET(fd, &srv->fdset));
374 	assert(srv->fdidx[fd].valid);
375 	assert(!srv->fdidx[fd].server);
376 	assert(srv->fdidx[fd].rsp != NULL);
377 	assert(srv->fdidx[fd].omtu >= NG_L2CAP_MTU_MINIMUM);
378 
379 	do {
380 		len = read(fd, srv->req, srv->imtu);
381 	} while (len < 0 && errno == EINTR);
382 
383 	if (len < 0) {
384 		log_err("Could not receive SDP request from %s socket. %s (%d)",
385 			srv->fdidx[fd].control? "control" : "L2CAP",
386 			strerror(errno), errno);
387 		return (-1);
388 	}
389 	if (len == 0) {
390 		log_info("Client on %s socket has disconnected",
391 			srv->fdidx[fd].control? "control" : "L2CAP");
392 		return (-1);
393 	}
394 
395 	if (sizeof(*pdu) + (pdu->len = ntohs(pdu->len)) == len) {
396 		switch (pdu->pid) {
397 		case SDP_PDU_SERVICE_SEARCH_REQUEST:
398 			error = server_prepare_service_search_response(srv, fd);
399 			break;
400 
401 		case SDP_PDU_SERVICE_ATTRIBUTE_REQUEST:
402 			error = server_prepare_service_attribute_response(srv, fd);
403 			break;
404 
405 		case SDP_PDU_SERVICE_SEARCH_ATTRIBUTE_REQUEST:
406 			error = server_prepare_service_search_attribute_response(srv, fd);
407 			break;
408 
409 		case SDP_PDU_SERVICE_REGISTER_REQUEST:
410 			error = server_prepare_service_register_response(srv, fd);
411 			break;
412 
413 		case SDP_PDU_SERVICE_UNREGISTER_REQUEST:
414 			error = server_prepare_service_unregister_response(srv, fd);
415 			break;
416 
417 		case SDP_PDU_SERVICE_CHANGE_REQUEST:
418 			error = server_prepare_service_change_response(srv, fd);
419 			break;
420 
421 		default:
422 			error = SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX;
423 			break;
424 		}
425 	} else
426 		error = SDP_ERROR_CODE_INVALID_PDU_SIZE;
427 
428 	if (error == 0) {
429 		switch (pdu->pid) {
430 		case SDP_PDU_SERVICE_SEARCH_REQUEST:
431 			error = server_send_service_search_response(srv, fd);
432 			break;
433 
434 		case SDP_PDU_SERVICE_ATTRIBUTE_REQUEST:
435 			error = server_send_service_attribute_response(srv, fd);
436 			break;
437 
438 		case SDP_PDU_SERVICE_SEARCH_ATTRIBUTE_REQUEST:
439 			error = server_send_service_search_attribute_response(srv, fd);
440 
441 break;
442 		case SDP_PDU_SERVICE_REGISTER_REQUEST:
443 			error = server_send_service_register_response(srv, fd);
444 			break;
445 
446 		case SDP_PDU_SERVICE_UNREGISTER_REQUEST:
447 			error = server_send_service_unregister_response(srv, fd);
448 			break;
449 
450 		case SDP_PDU_SERVICE_CHANGE_REQUEST:
451 			error = server_send_service_change_response(srv, fd);
452 
453 		default:
454 			error = SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX;
455 			break;
456 		}
457 
458 		if (error != 0)
459 			log_err("Could not send SDP response to %s socket, " \
460 				"pdu->pid=%d, pdu->tid=%d, error=%d",
461 				srv->fdidx[fd].control? "control" : "L2CAP",
462 				pdu->pid, ntohs(pdu->tid), error);
463 	} else {
464 		log_err("Could not process SDP request from %s socket, " \
465 			"pdu->pid=%d, pdu->tid=%d, pdu->len=%d, len=%d, " \
466 			"error=%d",
467 			srv->fdidx[fd].control? "control" : "L2CAP",
468 			pdu->pid, ntohs(pdu->tid), pdu->len, len, error);
469 
470 		error = server_send_error_response(srv, fd, error);
471 		if (error != 0)
472 			log_err("Could not send SDP error response to %s " \
473 				"socket, pdu->pid=%d, pdu->tid=%d, error=%d",
474 				srv->fdidx[fd].control? "control" : "L2CAP",
475 				pdu->pid, ntohs(pdu->tid), error);
476 	}
477 
478 	/* On error forget response (if any) */
479 	if (error != 0) {
480 		srv->fdidx[fd].rsp_cs = 0;
481 		srv->fdidx[fd].rsp_size = 0;
482 		srv->fdidx[fd].rsp_limit = 0;
483 	}
484 
485 	return (error);
486 }
487 
488 /*
489  * Send SDP_Error_Response PDU
490  */
491 
492 static int32_t
493 server_send_error_response(server_p srv, int32_t fd, uint16_t error)
494 {
495 	int32_t	size;
496 
497 	struct {
498 		sdp_pdu_t		pdu;
499 		uint16_t		error;
500 	} __attribute__ ((packed))	rsp;
501 
502 	/* Prepare and send SDP error response */
503 	rsp.pdu.pid = SDP_PDU_ERROR_RESPONSE;
504 	rsp.pdu.tid = ((sdp_pdu_p)(srv->req))->tid;
505 	rsp.pdu.len = htons(sizeof(rsp.error));
506 	rsp.error   = htons(error);
507 
508 	do {
509 		size = write(fd, &rsp, sizeof(rsp));
510 	} while (size < 0 && errno == EINTR);
511 
512 	return ((size < 0)? errno : 0);
513 }
514 
515 /*
516  * Close descriptor and remove it from index
517  */
518 
519 static void
520 server_close_fd(server_p srv, int32_t fd)
521 {
522 	provider_p	provider = NULL, provider_next = NULL;
523 
524 	assert(FD_ISSET(fd, &srv->fdset));
525 	assert(srv->fdidx[fd].valid);
526 
527 	close(fd);
528 
529 	FD_CLR(fd, &srv->fdset);
530 	if (fd == srv->maxfd)
531 		srv->maxfd --;
532 
533 	if (srv->fdidx[fd].rsp != NULL)
534 		free(srv->fdidx[fd].rsp);
535 
536 	memset(&srv->fdidx[fd], 0, sizeof(srv->fdidx[fd]));
537 
538 	for (provider = provider_get_first();
539 	     provider != NULL;
540 	     provider = provider_next) {
541 		provider_next = provider_get_next(provider);
542 
543 		if (provider->fd == fd)
544 			provider_unregister(provider);
545 	}
546 }
547 
548