1 /*
2 * @(#)res_mkquery.c 8.1 (Berkeley) 6/4/93
3 * $Id: res_mkquery.c,v 1.6.672.1 2008/04/03 02:12:21 marka Exp $
4 */
5
6 /*
7 * Copyright (c) 1985, 1993
8 * The Regents of the University of California. All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 /*
36 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
37 *
38 * Permission to use, copy, modify, and distribute this software for any
39 * purpose with or without fee is hereby granted, provided that the above
40 * copyright notice and this permission notice appear in all copies, and that
41 * the name of Digital Equipment Corporation not be used in advertising or
42 * publicity pertaining to distribution of the document or software without
43 * specific, written prior permission.
44 *
45 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
46 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
47 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
48 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
49 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
50 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
51 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
52 * SOFTWARE.
53 */
54
55 /*
56 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
57 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
58 *
59 * Permission to use, copy, modify, and distribute this software for any
60 * purpose with or without fee is hereby granted, provided that the above
61 * copyright notice and this permission notice appear in all copies.
62 *
63 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
64 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
65 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
66 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
67 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
68 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
69 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
70 */
71
72 #include "port_before.h"
73 #include <sys/types.h>
74 #include <sys/param.h>
75 #include <netinet/in.h>
76 #include <arpa/nameser.h>
77 #include <netdb.h>
78 #include <resolv.h>
79 #include <stdio.h>
80 #include <string.h>
81 #include "port_after.h"
82
83 /* Options. Leave them on. */
84 #define DEBUG
85
86 extern const char *_res_opcodes[];
87
88 /*%
89 * Form all types of queries.
90 * Returns the size of the result or -1.
91 */
92 int
res_nmkquery(res_state statp,int op,const char * dname,int class,int type,const u_char * data,int datalen,const u_char * newrr_in,u_char * buf,int buflen)93 res_nmkquery(res_state statp,
94 int op, /*!< opcode of query */
95 const char *dname, /*!< domain name */
96 int class, int type, /*!< class and type of query */
97 const u_char *data, /*!< resource record data */
98 int datalen, /*!< length of data */
99 const u_char *newrr_in, /*!< new rr for modify or append */
100 u_char *buf, /*!< buffer to put query */
101 int buflen) /*!< size of buffer */
102 {
103 HEADER *hp;
104 u_char *cp, *ep;
105 int n;
106 u_char *dnptrs[20], **dpp, **lastdnptr;
107
108 UNUSED(newrr_in);
109
110 #ifdef DEBUG
111 if (statp->options & RES_DEBUG)
112 printf(";; res_nmkquery(%s, %s, %s, %s)\n",
113 _res_opcodes[op], dname, p_class(class), p_type(type));
114 #endif
115 /*
116 * Initialize header fields.
117 */
118 if ((buf == NULL) || (buflen < HFIXEDSZ))
119 return (-1);
120 memset(buf, 0, HFIXEDSZ);
121 hp = (HEADER *) buf;
122 hp->id = htons(++statp->id);
123 hp->opcode = op;
124 hp->rd = (statp->options & RES_RECURSE) != 0U;
125 hp->rcode = NOERROR;
126 cp = buf + HFIXEDSZ;
127 ep = buf + buflen;
128 dpp = dnptrs;
129 *dpp++ = buf;
130 *dpp++ = NULL;
131 lastdnptr = dnptrs + NELEM(dnptrs);
132 /*
133 * perform opcode specific processing
134 */
135 switch (op) {
136 case QUERY: /*FALLTHROUGH*/
137 case NS_NOTIFY_OP:
138 if (ep - cp < QFIXEDSZ)
139 return (-1);
140 if ((n = dn_comp(dname, cp, ep - cp - QFIXEDSZ, dnptrs,
141 lastdnptr)) < 0)
142 return (-1);
143 cp += n;
144 ns_put16(type, cp);
145 cp += INT16SZ;
146 ns_put16(class, cp);
147 cp += INT16SZ;
148 hp->qdcount = htons(1);
149 if (op == QUERY || data == NULL)
150 break;
151 /*
152 * Make an additional record for completion domain.
153 */
154 if ((ep - cp) < RRFIXEDSZ)
155 return (-1);
156 n = dn_comp((const char *)data, cp, ep - cp - RRFIXEDSZ,
157 dnptrs, lastdnptr);
158 if (n < 0)
159 return (-1);
160 cp += n;
161 ns_put16(T_NULL, cp);
162 cp += INT16SZ;
163 ns_put16(class, cp);
164 cp += INT16SZ;
165 ns_put32(0, cp);
166 cp += INT32SZ;
167 ns_put16(0, cp);
168 cp += INT16SZ;
169 hp->arcount = htons(1);
170 break;
171
172 case IQUERY:
173 /*
174 * Initialize answer section
175 */
176 if (ep - cp < 1 + RRFIXEDSZ + datalen)
177 return (-1);
178 *cp++ = '\0'; /*%< no domain name */
179 ns_put16(type, cp);
180 cp += INT16SZ;
181 ns_put16(class, cp);
182 cp += INT16SZ;
183 ns_put32(0, cp);
184 cp += INT32SZ;
185 ns_put16(datalen, cp);
186 cp += INT16SZ;
187 if (datalen) {
188 memcpy(cp, data, datalen);
189 cp += datalen;
190 }
191 hp->ancount = htons(1);
192 break;
193
194 default:
195 return (-1);
196 }
197 return (cp - buf);
198 }
199
200 #ifdef RES_USE_EDNS0
201 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
202
203 int
res_nopt(res_state statp,int n0,u_char * buf,int buflen,int anslen)204 res_nopt(res_state statp,
205 int n0, /*%< current offset in buffer */
206 u_char *buf, /*%< buffer to put query */
207 int buflen, /*%< size of buffer */
208 int anslen) /*%< UDP answer buffer size */
209 {
210 HEADER *hp;
211 u_char *cp, *ep;
212 u_int16_t flags = 0;
213
214 #ifdef DEBUG
215 if ((statp->options & RES_DEBUG) != 0U)
216 printf(";; res_nopt()\n");
217 #endif
218
219 hp = (HEADER *) buf;
220 cp = buf + n0;
221 ep = buf + buflen;
222
223 if ((ep - cp) < 1 + RRFIXEDSZ)
224 return (-1);
225
226 *cp++ = 0; /*%< "." */
227 ns_put16(ns_t_opt, cp); /*%< TYPE */
228 cp += INT16SZ;
229 if (anslen > 0xffff)
230 anslen = 0xffff;
231 ns_put16(anslen & 0xffff, cp); /*%< CLASS = UDP payload size */
232 cp += INT16SZ;
233 *cp++ = NOERROR; /*%< extended RCODE */
234 *cp++ = 0; /*%< EDNS version */
235
236 if (statp->options & RES_USE_DNSSEC) {
237 #ifdef DEBUG
238 if (statp->options & RES_DEBUG)
239 printf(";; res_opt()... ENDS0 DNSSEC\n");
240 #endif
241 flags |= NS_OPT_DNSSEC_OK;
242 }
243 ns_put16(flags, cp);
244 cp += INT16SZ;
245
246 ns_put16(0U, cp); /*%< RDLEN */
247 cp += INT16SZ;
248
249 hp->arcount = htons(ntohs(hp->arcount) + 1);
250
251 return (cp - buf);
252 }
253
254 /*
255 * Construct variable data (RDATA) block for OPT psuedo-RR, append it
256 * to the buffer, then update the RDLEN field (previously set to zero by
257 * res_nopt()) with the new RDATA length.
258 */
259 int
res_nopt_rdata(res_state statp,int n0,u_char * buf,int buflen,u_char * rdata,u_short code,u_short len,u_char * data)260 res_nopt_rdata(res_state statp,
261 int n0, /*%< current offset in buffer */
262 u_char *buf, /*%< buffer to put query */
263 int buflen, /*%< size of buffer */
264 u_char *rdata, /*%< ptr to start of opt rdata */
265 u_short code, /*%< OPTION-CODE */
266 u_short len, /*%< OPTION-LENGTH */
267 u_char *data) /*%< OPTION_DATA */
268 {
269 u_char *cp, *ep;
270
271 #ifdef DEBUG
272 if ((statp->options & RES_DEBUG) != 0U)
273 printf(";; res_nopt_rdata()\n");
274 #endif
275
276 cp = buf + n0;
277 ep = buf + buflen;
278
279 if ((ep - cp) < (4 + len))
280 return (-1);
281
282 if (rdata < (buf + 2) || rdata >= ep)
283 return (-1);
284
285 ns_put16(code, cp);
286 cp += INT16SZ;
287
288 ns_put16(len, cp);
289 cp += INT16SZ;
290
291 memcpy(cp, data, len);
292 cp += len;
293
294 len = cp - rdata;
295 ns_put16(len, rdata - 2); /* Update RDLEN field */
296
297 return (cp - buf);
298 }
299 #endif
300
301 /*! \file */
302