xref: /freebsd/usr.sbin/bluetooth/sdpd/sar.c (revision e8e8c939350bdf3c228a411caa9660c607c27a11)
1 /*
2  * sar.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: sar.c,v 1.2 2004/01/08 23:46:51 max Exp $
29  * $FreeBSD$
30  */
31 
32 #include <sys/queue.h>
33 #include <sys/uio.h>
34 #include <netinet/in.h>
35 #include <arpa/inet.h>
36 #include <assert.h>
37 #define L2CAP_SOCKET_CHECKED
38 #include <bluetooth.h>
39 #include <errno.h>
40 #include <sdp.h>
41 #include <stdio.h> /* for NULL */
42 #include "profile.h"
43 #include "provider.h"
44 #include "server.h"
45 
46 /*
47  * Prepare SDP attr/value pair. Check if profile implements the attribute
48  * and if so call the attribute value function.
49  *
50  * uint16 value16	- 3 bytes (attribute)
51  * value		- N bytes (value)
52  */
53 
54 static int32_t
55 server_prepare_attr_value_pair(
56 		provider_p const provider, uint16_t attr,
57 		uint8_t *buf, uint8_t const * const eob)
58 {
59 	profile_attr_create_p	cf = profile_get_attr(provider->profile, attr);
60 	int32_t			len;
61 
62 	if (cf == NULL)
63 		return (0); /* no attribute */
64 
65 	if (buf + 3 > eob)
66 		return (-1);
67 
68 	SDP_PUT8(SDP_DATA_UINT16, buf);
69 	SDP_PUT16(attr, buf);
70 
71 	len = cf(buf, eob, (uint8_t const *) provider, sizeof(*provider));
72 	if (len < 0)
73 		return (-1);
74 
75 	return (3 + len);
76 }
77 
78 /*
79  * seq16 value16	- 3 bytes
80  *	attr value	- 3+ bytes
81  *	[ attr value ]
82  */
83 
84 int32_t
85 server_prepare_attr_list(provider_p const provider,
86 		uint8_t const *req, uint8_t const * const req_end,
87 		uint8_t *rsp, uint8_t const * const rsp_end)
88 {
89 	uint8_t	*ptr = rsp + 3;
90 	int32_t	 type, hi, lo, len;
91 
92 	if (ptr > rsp_end)
93 		return (-1);
94 
95 	while (req < req_end) {
96 		SDP_GET8(type, req);
97 
98 		switch (type) {
99 		case SDP_DATA_UINT16:
100 			if (req + 2 > req_end)
101 				return (-1);
102 
103 			SDP_GET16(lo, req);
104 			hi = lo;
105 			break;
106 
107 		case SDP_DATA_UINT32:
108 			if (req + 4 > req_end)
109 				return (-1);
110 
111 			SDP_GET16(lo, req);
112 			SDP_GET16(hi, req);
113 			break;
114 
115 		default:
116 			return (-1);
117 			/* NOT REACHED */
118 		}
119 
120 		for (; lo <= hi; lo ++) {
121 			len = server_prepare_attr_value_pair(provider, lo, ptr, rsp_end);
122 			if (len < 0)
123 				return (-1);
124 
125 			ptr += len;
126 		}
127 	}
128 
129 	len = ptr - rsp; /* we put this much bytes in rsp */
130 
131 	/* Fix SEQ16 header for the rsp */
132 	SDP_PUT8(SDP_DATA_SEQ16, rsp);
133 	SDP_PUT16(len - 3, rsp);
134 
135 	return (len);
136 }
137 
138 /*
139  * Prepare SDP Service Attribute Response
140  */
141 
142 int32_t
143 server_prepare_service_attribute_response(server_p srv, int32_t fd)
144 {
145 	uint8_t const	*req = srv->req + sizeof(sdp_pdu_t);
146 	uint8_t const	*req_end = req + ((sdp_pdu_p)(srv->req))->len;
147 	uint8_t		*rsp = srv->fdidx[fd].rsp;
148 	uint8_t const	*rsp_end = rsp + NG_L2CAP_MTU_MAXIMUM;
149 
150 	uint8_t		*ptr = NULL;
151 	provider_t	*provider = NULL;
152 	uint32_t	 handle;
153 	int32_t		 type, rsp_limit, aidlen, cslen, cs;
154 
155 	/*
156 	 * Minimal Service Attribute Request request
157 	 *
158 	 * value32		- 4 bytes ServiceRecordHandle
159 	 * value16		- 2 bytes MaximumAttributeByteCount
160 	 * seq8 len8		- 2 bytes
161 	 *	uint16 value16	- 3 bytes AttributeIDList
162 	 * value8		- 1 byte  ContinuationState
163 	 */
164 
165 	if (req_end - req < 12)
166 		return (SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX);
167 
168 	/* Get ServiceRecordHandle and MaximumAttributeByteCount */
169 	SDP_GET32(handle, req);
170 	SDP_GET16(rsp_limit, req);
171 	if (rsp_limit <= 0)
172 		return (SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX);
173 
174 	/* Get size of AttributeIDList */
175 	aidlen = 0;
176 	SDP_GET8(type, req);
177 	switch (type) {
178 	case SDP_DATA_SEQ8:
179 		SDP_GET8(aidlen, req);
180 		break;
181 
182 	case SDP_DATA_SEQ16:
183 		SDP_GET16(aidlen, req);
184 		break;
185 
186 	case SDP_DATA_SEQ32:
187 		SDP_GET32(aidlen, req);
188  		break;
189 	}
190 	if (aidlen <= 0)
191 		return (SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX);
192 
193 	ptr = (uint8_t *) req + aidlen;
194 
195 	/* Get ContinuationState */
196 	if (ptr + 1 > req_end)
197 		return (SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX);
198 
199 	SDP_GET8(cslen, ptr);
200 	if (cslen != 0) {
201 		if (cslen != 2 || req_end - ptr != 2)
202 			return (SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX);
203 
204 		SDP_GET16(cs, ptr);
205 	} else
206 		cs = 0;
207 
208 	/* Process the request. First, check continuation state */
209 	if (srv->fdidx[fd].rsp_cs != cs)
210 		return (SDP_ERROR_CODE_INVALID_CONTINUATION_STATE);
211 	if (srv->fdidx[fd].rsp_size > 0)
212 		return (0);
213 
214 	/* Lookup record handle */
215 	if ((provider = provider_by_handle(handle)) == NULL)
216 		return (SDP_ERROR_CODE_INVALID_SERVICE_RECORD_HANDLE);
217 
218 	/*
219 	 * Service Attribute Response format
220 	 *
221 	 * value16		- 2 bytes  AttributeListByteCount (not incl.)
222 	 * seq8 len16		- 3 bytes
223 	 *	attr value	- 3+ bytes AttributeList
224 	 *	[ attr value ]
225 	 */
226 
227 	cs = server_prepare_attr_list(provider, req, req+aidlen, rsp, rsp_end);
228 	if (cs < 0)
229 		return (SDP_ERROR_CODE_INSUFFICIENT_RESOURCES);
230 
231 	/* Set reply size (not counting PDU header and continuation state) */
232 	srv->fdidx[fd].rsp_limit = srv->fdidx[fd].omtu - sizeof(sdp_pdu_t) - 2;
233 	if (srv->fdidx[fd].rsp_limit > rsp_limit)
234 		srv->fdidx[fd].rsp_limit = rsp_limit;
235 
236 	srv->fdidx[fd].rsp_size = cs;
237 	srv->fdidx[fd].rsp_cs = 0;
238 
239 	return (0);
240 }
241 
242 /*
243  * Send SDP Service [Search] Attribute Response
244  */
245 
246 int32_t
247 server_send_service_attribute_response(server_p srv, int32_t fd)
248 {
249 	uint8_t		*rsp = srv->fdidx[fd].rsp + srv->fdidx[fd].rsp_cs;
250 	uint8_t		*rsp_end = srv->fdidx[fd].rsp + srv->fdidx[fd].rsp_size;
251 
252 	struct iovec	iov[4];
253 	sdp_pdu_t	pdu;
254 	uint16_t	bcount;
255 	uint8_t		cs[3];
256 	int32_t		size;
257 
258 	/* First update continuation state  (assume we will send all data) */
259 	size = rsp_end - rsp;
260 	srv->fdidx[fd].rsp_cs += size;
261 
262 	if (size + 1 > srv->fdidx[fd].rsp_limit) {
263 		/*
264 		 * We need to split out response. Add 3 more bytes for the
265 		 * continuation state and move rsp_end and rsp_cs backwards.
266 		 */
267 
268 		while ((rsp_end - rsp) + 3 > srv->fdidx[fd].rsp_limit) {
269 			rsp_end --;
270 			srv->fdidx[fd].rsp_cs --;
271 		}
272 
273 		cs[0] = 2;
274 		cs[1] = srv->fdidx[fd].rsp_cs >> 8;
275 		cs[2] = srv->fdidx[fd].rsp_cs & 0xff;
276 	} else
277 		cs[0] = 0;
278 
279 	assert(rsp_end >= rsp);
280 
281 	bcount = rsp_end - rsp;
282 
283 	if (((sdp_pdu_p)(srv->req))->pid == SDP_PDU_SERVICE_ATTRIBUTE_REQUEST)
284 		pdu.pid = SDP_PDU_SERVICE_ATTRIBUTE_RESPONSE;
285 	else
286 		pdu.pid = SDP_PDU_SERVICE_SEARCH_ATTRIBUTE_RESPONSE;
287 
288 	pdu.tid = ((sdp_pdu_p)(srv->req))->tid;
289 	pdu.len = htons(sizeof(bcount) + bcount + 1 + cs[0]);
290 
291 	bcount = htons(bcount);
292 
293 	iov[0].iov_base = &pdu;
294 	iov[0].iov_len = sizeof(pdu);
295 
296 	iov[1].iov_base = &bcount;
297 	iov[1].iov_len = sizeof(bcount);
298 
299 	iov[2].iov_base = rsp;
300 	iov[2].iov_len = rsp_end - rsp;
301 
302 	iov[3].iov_base = cs;
303 	iov[3].iov_len = 1 + cs[0];
304 
305 	do {
306 		size = writev(fd, (struct iovec const *) &iov, sizeof(iov)/sizeof(iov[0]));
307 	} while (size < 0 && errno == EINTR);
308 
309 	/* Check if we have sent (or failed to sent) last response chunk */
310 	if (srv->fdidx[fd].rsp_cs == srv->fdidx[fd].rsp_size) {
311 		srv->fdidx[fd].rsp_cs = 0;
312 		srv->fdidx[fd].rsp_size = 0;
313 		srv->fdidx[fd].rsp_limit = 0;
314 	}
315 
316 	return ((size < 0)? errno : 0);
317 }
318 
319