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
server_prepare_attr_value_pair(provider_p const provider,uint16_t attr,uint8_t * buf,uint8_t const * const eob)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
server_prepare_attr_list(provider_p const provider,uint8_t const * req,uint8_t const * const req_end,uint8_t * rsp,uint8_t const * const rsp_end)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
server_prepare_service_attribute_response(server_p srv,int32_t fd)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
server_send_service_attribute_response(server_p srv,int32_t fd)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