xref: /freebsd/usr.sbin/bluetooth/sdpd/sar.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
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 #include <bluetooth.h>
38 #include <errno.h>
39 #include <sdp.h>
40 #include <stdio.h> /* for NULL */
41 #include "profile.h"
42 #include "provider.h"
43 #include "server.h"
44 
45 /*
46  * Prepare SDP attr/value pair. Check if profile implements the attribute
47  * and if so call the attribute value function.
48  *
49  * uint16 value16	- 3 bytes (attribute)
50  * value		- N bytes (value)
51  */
52 
53 static int32_t
54 server_prepare_attr_value_pair(
55 		provider_p const provider, uint16_t attr,
56 		uint8_t *buf, uint8_t const * const eob)
57 {
58 	profile_attr_create_p	cf = profile_get_attr(provider->profile, attr);
59 	int32_t			len;
60 
61 	if (cf == NULL)
62 		return (0); /* no attribute */
63 
64 	if (buf + 3 > eob)
65 		return (-1);
66 
67 	SDP_PUT8(SDP_DATA_UINT16, buf);
68 	SDP_PUT16(attr, buf);
69 
70 	len = cf(buf, eob, (uint8_t const *) provider, sizeof(*provider));
71 	if (len < 0)
72 		return (-1);
73 
74 	return (3 + len);
75 }
76 
77 /*
78  * seq16 value16	- 3 bytes
79  *	attr value	- 3+ bytes
80  *	[ attr value ]
81  */
82 
83 int32_t
84 server_prepare_attr_list(provider_p const provider,
85 		uint8_t const *req, uint8_t const * const req_end,
86 		uint8_t *rsp, uint8_t const * const rsp_end)
87 {
88 	uint8_t	*ptr = rsp + 3;
89 	int32_t	 type, hi, lo, len;
90 
91 	if (ptr > rsp_end)
92 		return (-1);
93 
94 	while (req < req_end) {
95 		SDP_GET8(type, req);
96 
97 		switch (type) {
98 		case SDP_DATA_UINT16:
99 			if (req + 2 > req_end)
100 				return (-1);
101 
102 			SDP_GET16(lo, req);
103 			hi = lo;
104 			break;
105 
106 		case SDP_DATA_UINT32:
107 			if (req + 4 > req_end)
108 				return (-1);
109 
110 			SDP_GET16(lo, req);
111 			SDP_GET16(hi, req);
112 			break;
113 
114 		default:
115 			return (-1);
116 			/* NOT REACHED */
117 		}
118 
119 		for (; lo <= hi; lo ++) {
120 			len = server_prepare_attr_value_pair(provider, lo, ptr, rsp_end);
121 			if (len < 0)
122 				return (-1);
123 
124 			ptr += len;
125 		}
126 	}
127 
128 	len = ptr - rsp; /* we put this much bytes in rsp */
129 
130 	/* Fix SEQ16 header for the rsp */
131 	SDP_PUT8(SDP_DATA_SEQ16, rsp);
132 	SDP_PUT16(len - 3, rsp);
133 
134 	return (len);
135 }
136 
137 /*
138  * Prepare SDP Service Attribute Response
139  */
140 
141 int32_t
142 server_prepare_service_attribute_response(server_p srv, int32_t fd)
143 {
144 	uint8_t const	*req = srv->req + sizeof(sdp_pdu_t);
145 	uint8_t const	*req_end = req + ((sdp_pdu_p)(srv->req))->len;
146 	uint8_t		*rsp = srv->fdidx[fd].rsp;
147 	uint8_t const	*rsp_end = rsp + NG_L2CAP_MTU_MAXIMUM;
148 
149 	uint8_t		*ptr = NULL;
150 	provider_t	*provider = NULL;
151 	uint32_t	 handle;
152 	int32_t		 type, rsp_limit, aidlen, cslen, cs;
153 
154 	/*
155 	 * Minimal Service Attribute Request request
156 	 *
157 	 * value32		- 4 bytes ServiceRecordHandle
158 	 * value16		- 2 bytes MaximumAttributeByteCount
159 	 * seq8 len8		- 2 bytes
160 	 *	uint16 value16	- 3 bytes AttributeIDList
161 	 * value8		- 1 byte  ContinuationState
162 	 */
163 
164 	if (req_end - req < 12)
165 		return (SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX);
166 
167 	/* Get ServiceRecordHandle and MaximumAttributeByteCount */
168 	SDP_GET32(handle, req);
169 	SDP_GET16(rsp_limit, req);
170 	if (rsp_limit <= 0)
171 		return (SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX);
172 
173 	/* Get size of AttributeIDList */
174 	aidlen = 0;
175 	SDP_GET8(type, req);
176 	switch (type) {
177 	case SDP_DATA_SEQ8:
178 		SDP_GET8(aidlen, req);
179 		break;
180 
181 	case SDP_DATA_SEQ16:
182 		SDP_GET16(aidlen, req);
183 		break;
184 
185 	case SDP_DATA_SEQ32:
186 		SDP_GET32(aidlen, req);
187  		break;
188 	}
189 	if (aidlen <= 0)
190 		return (SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX);
191 
192 	ptr = (uint8_t *) req + aidlen;
193 
194 	/* Get ContinuationState */
195 	if (ptr + 1 > req_end)
196 		return (SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX);
197 
198 	SDP_GET8(cslen, ptr);
199 	if (cslen != 0) {
200 		if (cslen != 2 || req_end - ptr != 2)
201 			return (SDP_ERROR_CODE_INVALID_REQUEST_SYNTAX);
202 
203 		SDP_GET16(cs, ptr);
204 	} else
205 		cs = 0;
206 
207 	/* Process the request. First, check continuation state */
208 	if (srv->fdidx[fd].rsp_cs != cs)
209 		return (SDP_ERROR_CODE_INVALID_CONTINUATION_STATE);
210 	if (srv->fdidx[fd].rsp_size > 0)
211 		return (0);
212 
213 	/* Lookup record handle */
214 	if ((provider = provider_by_handle(handle)) == NULL)
215 		return (SDP_ERROR_CODE_INVALID_SERVICE_RECORD_HANDLE);
216 
217 	/*
218 	 * Service Attribute Response format
219 	 *
220 	 * value16		- 2 bytes  AttributeListByteCount (not incl.)
221 	 * seq8 len16		- 3 bytes
222 	 *	attr value	- 3+ bytes AttributeList
223 	 *	[ attr value ]
224 	 */
225 
226 	cs = server_prepare_attr_list(provider, req, req+aidlen, rsp, rsp_end);
227 	if (cs < 0)
228 		return (SDP_ERROR_CODE_INSUFFICIENT_RESOURCES);
229 
230 	/* Set reply size (not counting PDU header and continuation state) */
231 	srv->fdidx[fd].rsp_limit = srv->fdidx[fd].omtu - sizeof(sdp_pdu_t) - 2;
232 	if (srv->fdidx[fd].rsp_limit > rsp_limit)
233 		srv->fdidx[fd].rsp_limit = rsp_limit;
234 
235 	srv->fdidx[fd].rsp_size = cs;
236 	srv->fdidx[fd].rsp_cs = 0;
237 
238 	return (0);
239 }
240 
241 /*
242  * Send SDP Service [Search] Attribute Response
243  */
244 
245 int32_t
246 server_send_service_attribute_response(server_p srv, int32_t fd)
247 {
248 	uint8_t		*rsp = srv->fdidx[fd].rsp + srv->fdidx[fd].rsp_cs;
249 	uint8_t		*rsp_end = srv->fdidx[fd].rsp + srv->fdidx[fd].rsp_size;
250 
251 	struct iovec	iov[4];
252 	sdp_pdu_t	pdu;
253 	uint16_t	bcount;
254 	uint8_t		cs[3];
255 	int32_t		size;
256 
257 	/* First update continuation state  (assume we will send all data) */
258 	size = rsp_end - rsp;
259 	srv->fdidx[fd].rsp_cs += size;
260 
261 	if (size + 1 > srv->fdidx[fd].rsp_limit) {
262 		/*
263 		 * We need to split out response. Add 3 more bytes for the
264 		 * continuation state and move rsp_end and rsp_cs backwards.
265 		 */
266 
267 		while ((rsp_end - rsp) + 3 > srv->fdidx[fd].rsp_limit) {
268 			rsp_end --;
269 			srv->fdidx[fd].rsp_cs --;
270 		}
271 
272 		cs[0] = 2;
273 		cs[1] = srv->fdidx[fd].rsp_cs >> 8;
274 		cs[2] = srv->fdidx[fd].rsp_cs & 0xff;
275 	} else
276 		cs[0] = 0;
277 
278 	assert(rsp_end >= rsp);
279 
280 	bcount = rsp_end - rsp;
281 
282 	if (((sdp_pdu_p)(srv->req))->pid == SDP_PDU_SERVICE_ATTRIBUTE_REQUEST)
283 		pdu.pid = SDP_PDU_SERVICE_ATTRIBUTE_RESPONSE;
284 	else
285 		pdu.pid = SDP_PDU_SERVICE_SEARCH_ATTRIBUTE_RESPONSE;
286 
287 	pdu.tid = ((sdp_pdu_p)(srv->req))->tid;
288 	pdu.len = htons(sizeof(bcount) + bcount + 1 + cs[0]);
289 
290 	bcount = htons(bcount);
291 
292 	iov[0].iov_base = &pdu;
293 	iov[0].iov_len = sizeof(pdu);
294 
295 	iov[1].iov_base = &bcount;
296 	iov[1].iov_len = sizeof(bcount);
297 
298 	iov[2].iov_base = rsp;
299 	iov[2].iov_len = rsp_end - rsp;
300 
301 	iov[3].iov_base = cs;
302 	iov[3].iov_len = 1 + cs[0];
303 
304 	do {
305 		size = writev(fd, (struct iovec const *) &iov, sizeof(iov)/sizeof(iov[0]));
306 	} while (size < 0 && errno == EINTR);
307 
308 	/* Check if we have sent (or failed to sent) last response chunk */
309 	if (srv->fdidx[fd].rsp_cs == srv->fdidx[fd].rsp_size) {
310 		srv->fdidx[fd].rsp_cs = 0;
311 		srv->fdidx[fd].rsp_size = 0;
312 		srv->fdidx[fd].rsp_limit = 0;
313 	}
314 
315 	return ((size < 0)? errno : 0);
316 }
317 
318