res_mkquery.c revision 1.9 1 /* $NetBSD: res_mkquery.c,v 1.9 2008/06/21 20:41:48 christos Exp $ */
2
3 /*
4 * Copyright (c) 1985, 1993
5 * The Regents of the University of California. 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 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by the University of
18 * California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 /*
37 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
38 *
39 * Permission to use, copy, modify, and distribute this software for any
40 * purpose with or without fee is hereby granted, provided that the above
41 * copyright notice and this permission notice appear in all copies, and that
42 * the name of Digital Equipment Corporation not be used in advertising or
43 * publicity pertaining to distribution of the document or software without
44 * specific, written prior permission.
45 *
46 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
47 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
48 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
49 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
50 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
51 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
52 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
53 * SOFTWARE.
54 */
55
56 /*
57 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
58 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
59 *
60 * Permission to use, copy, modify, and distribute this software for any
61 * purpose with or without fee is hereby granted, provided that the above
62 * copyright notice and this permission notice appear in all copies.
63 *
64 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
65 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
66 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
67 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
68 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
69 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
70 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
71 */
72
73 #include <sys/cdefs.h>
74 #if defined(LIBC_SCCS) && !defined(lint)
75 #ifdef notdef
76 static const char sccsid[] = "@(#)res_mkquery.c 8.1 (Berkeley) 6/4/93";
77 static const char rcsid[] = "Id: res_mkquery.c,v 1.6.672.1 2008/04/03 02:12:21 marka Exp";
78 #else
79 __RCSID("$NetBSD: res_mkquery.c,v 1.9 2008/06/21 20:41:48 christos Exp $");
80 #endif
81 #endif /* LIBC_SCCS and not lint */
82
83 #include "port_before.h"
84
85 #include "namespace.h"
86 #include <sys/types.h>
87 #include <sys/param.h>
88 #include <netinet/in.h>
89 #include <arpa/nameser.h>
90 #include <netdb.h>
91 #include <resolv.h>
92 #include <stdio.h>
93 #include <string.h>
94 #include "port_after.h"
95
96 #if 0
97 #ifdef __weak_alias
98 __weak_alias(res_nmkquery,_res_nmkquery)
99 __weak_alias(res_nopt,_res_nopt)
100 #endif
101 #endif
102
103 /* Options. Leave them on. */
104 #define DEBUG
105
106 extern const char *_res_opcodes[];
107
108 /*%
109 * Form all types of queries.
110 * Returns the size of the result or -1.
111 */
112 int
113 res_nmkquery(res_state statp,
114 int op, /*!< opcode of query */
115 const char *dname, /*!< domain name */
116 int class, int type, /*!< class and type of query */
117 const u_char *data, /*!< resource record data */
118 int datalen, /*!< length of data */
119 const u_char *newrr_in, /*!< new rr for modify or append */
120 u_char *buf, /*!< buffer to put query */
121 int buflen) /*!< size of buffer */
122 {
123 register HEADER *hp;
124 register u_char *cp, *ep;
125 register int n;
126 u_char *dnptrs[20], **dpp, **lastdnptr;
127
128 UNUSED(newrr_in);
129
130 #ifdef DEBUG
131 if (statp->options & RES_DEBUG)
132 printf(";; res_nmkquery(%s, %s, %s, %s)\n",
133 _res_opcodes[op], dname, p_class(class), p_type(type));
134 #endif
135 /*
136 * Initialize header fields.
137 */
138 if ((buf == NULL) || (buflen < HFIXEDSZ))
139 return (-1);
140 memset(buf, 0, HFIXEDSZ);
141 hp = (HEADER *)(void *)buf;
142 hp->id = htons(++statp->id);
143 hp->opcode = op;
144 hp->rd = (statp->options & RES_RECURSE) != 0U;
145 hp->rcode = NOERROR;
146 cp = buf + HFIXEDSZ;
147 ep = buf + buflen;
148 dpp = dnptrs;
149 *dpp++ = buf;
150 *dpp++ = NULL;
151 lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
152 /*
153 * perform opcode specific processing
154 */
155 switch (op) {
156 case QUERY: /*FALLTHROUGH*/
157 case NS_NOTIFY_OP:
158 if (ep - cp < QFIXEDSZ)
159 return (-1);
160 if ((n = dn_comp(dname, cp, ep - cp - QFIXEDSZ, dnptrs,
161 lastdnptr)) < 0)
162 return (-1);
163 cp += n;
164 ns_put16(type, cp);
165 cp += INT16SZ;
166 ns_put16(class, cp);
167 cp += INT16SZ;
168 hp->qdcount = htons(1);
169 if (op == QUERY || data == NULL)
170 break;
171 /*
172 * Make an additional record for completion domain.
173 */
174 if ((ep - cp) < RRFIXEDSZ)
175 return (-1);
176 n = dn_comp((const char *)data, cp, ep - cp - RRFIXEDSZ,
177 dnptrs, lastdnptr);
178 if (n < 0)
179 return (-1);
180 cp += n;
181 ns_put16(T_NULL, cp);
182 cp += INT16SZ;
183 ns_put16(class, cp);
184 cp += INT16SZ;
185 ns_put32(0, cp);
186 cp += INT32SZ;
187 ns_put16(0, cp);
188 cp += INT16SZ;
189 hp->arcount = htons(1);
190 break;
191
192 case IQUERY:
193 /*
194 * Initialize answer section
195 */
196 if (ep - cp < 1 + RRFIXEDSZ + datalen)
197 return (-1);
198 *cp++ = '\0'; /*%< no domain name */
199 ns_put16(type, cp);
200 cp += INT16SZ;
201 ns_put16(class, cp);
202 cp += INT16SZ;
203 ns_put32(0, cp);
204 cp += INT32SZ;
205 ns_put16(datalen, cp);
206 cp += INT16SZ;
207 if (datalen) {
208 memcpy(cp, data, (size_t)datalen);
209 cp += datalen;
210 }
211 hp->ancount = htons(1);
212 break;
213
214 default:
215 return (-1);
216 }
217 return (cp - buf);
218 }
219
220 #ifdef RES_USE_EDNS0
221 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
222
223 int
224 res_nopt(res_state statp,
225 int n0, /*%< current offset in buffer */
226 u_char *buf, /*%< buffer to put query */
227 int buflen, /*%< size of buffer */
228 int anslen) /*%< UDP answer buffer size */
229 {
230 register HEADER *hp;
231 register u_char *cp, *ep;
232 u_int16_t flags = 0;
233
234 #ifdef DEBUG
235 if ((statp->options & RES_DEBUG) != 0U)
236 printf(";; res_nopt()\n");
237 #endif
238
239 hp = (HEADER *)(void *)buf;
240 cp = buf + n0;
241 ep = buf + buflen;
242
243 if ((ep - cp) < 1 + RRFIXEDSZ)
244 return (-1);
245
246 *cp++ = 0; /*%< "." */
247 ns_put16(ns_t_opt, cp); /*%< TYPE */
248 cp += INT16SZ;
249 ns_put16(anslen & 0xffff, cp); /*%< CLASS = UDP payload size */
250 cp += INT16SZ;
251 *cp++ = NOERROR; /*%< extended RCODE */
252 *cp++ = 0; /*%< EDNS version */
253
254 if (statp->options & RES_USE_DNSSEC) {
255 #ifdef DEBUG
256 if (statp->options & RES_DEBUG)
257 printf(";; res_opt()... ENDS0 DNSSEC\n");
258 #endif
259 flags |= NS_OPT_DNSSEC_OK;
260 }
261 ns_put16(flags, cp);
262 cp += INT16SZ;
263
264 ns_put16(0U, cp); /*%< RDLEN */
265 cp += INT16SZ;
266
267 hp->arcount = htons(ntohs(hp->arcount) + 1);
268
269 return (cp - buf);
270 }
271
272 /*
273 * Construct variable data (RDATA) block for OPT psuedo-RR, append it
274 * to the buffer, then update the RDLEN field (previously set to zero by
275 * res_nopt()) with the new RDATA length.
276 */
277 int
278 res_nopt_rdata(res_state statp,
279 int n0, /*%< current offset in buffer */
280 u_char *buf, /*%< buffer to put query */
281 int buflen, /*%< size of buffer */
282 u_char *rdata, /*%< ptr to start of opt rdata */
283 u_short code, /*%< OPTION-CODE */
284 u_short len, /*%< OPTION-LENGTH */
285 u_char *data) /*%< OPTION_DATA */
286 {
287 register u_char *cp, *ep;
288
289 #ifdef DEBUG
290 if ((statp->options & RES_DEBUG) != 0U)
291 printf(";; res_nopt_rdata()\n");
292 #endif
293
294 cp = buf + n0;
295 ep = buf + buflen;
296
297 if ((ep - cp) < (4 + len))
298 return (-1);
299
300 if (rdata < (buf + 2) || rdata >= ep)
301 return (-1);
302
303 ns_put16(code, cp);
304 cp += INT16SZ;
305
306 ns_put16(len, cp);
307 cp += INT16SZ;
308
309 memcpy(cp, data, len);
310 cp += len;
311
312 len = cp - rdata;
313 ns_put16(len, rdata - 2); /* Update RDLEN field */
314
315 return (cp - buf);
316 }
317 #endif
318
319 /*! \file */
320