1 /* $NetBSD: res_mkquery.c,v 1.15 2015/02/24 17:56:20 christos Exp $ */
2
3 /*
4 * Portions Copyright (C) 2004, 2005, 2008 Internet Systems Consortium, Inc. ("ISC")
5 * Portions Copyright (C) 1996, 1997, 1988, 1999, 2001, 2003 Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and/or distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
12 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
13 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
14 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17 * PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 /*
21 * Copyright (c) 1985, 1993
22 * The Regents of the University of California. All rights reserved.
23 *
24 * Redistribution and use in source and binary forms, with or without
25 * modification, are permitted provided that the following conditions
26 * are met:
27 * 1. Redistributions of source code must retain the above copyright
28 * notice, this list of conditions and the following disclaimer.
29 * 2. Redistributions in binary form must reproduce the above copyright
30 * notice, this list of conditions and the following disclaimer in the
31 * documentation and/or other materials provided with the distribution.
32 * 3. Neither the name of the University nor the names of its contributors
33 * may be used to endorse or promote products derived from this software
34 * without specific prior written permission.
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
37 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
40 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
41 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
42 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
44 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
45 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46 * SUCH DAMAGE.
47 */
48
49 /*
50 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
51 *
52 * Permission to use, copy, modify, and distribute this software for any
53 * purpose with or without fee is hereby granted, provided that the above
54 * copyright notice and this permission notice appear in all copies, and that
55 * the name of Digital Equipment Corporation not be used in advertising or
56 * publicity pertaining to distribution of the document or software without
57 * specific, written prior permission.
58 *
59 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
60 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
61 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
62 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
63 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
64 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
65 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
66 * SOFTWARE.
67 */
68
69 #include <sys/cdefs.h>
70 #if defined(LIBC_SCCS) && !defined(lint)
71 #ifdef notdef
72 static const char sccsid[] = "@(#)res_mkquery.c 8.1 (Berkeley) 6/4/93";
73 static const char rcsid[] = "Id: res_mkquery.c,v 1.10 2008/12/11 09:59:00 marka Exp";
74 #else
75 __RCSID("$NetBSD: res_mkquery.c,v 1.15 2015/02/24 17:56:20 christos Exp $");
76 #endif
77 #endif /* LIBC_SCCS and not lint */
78
79 #include "port_before.h"
80
81 #include "namespace.h"
82 #include <sys/types.h>
83 #include <sys/param.h>
84 #include <netinet/in.h>
85 #include <arpa/nameser.h>
86 #include <assert.h>
87 #include <netdb.h>
88 #include <resolv.h>
89 #include <stdio.h>
90 #include <string.h>
91 #include "port_after.h"
92
93 #if 0
94 #ifdef __weak_alias
95 __weak_alias(res_nmkquery,_res_nmkquery)
96 __weak_alias(res_nopt,_res_nopt)
97 #endif
98 #endif
99
100 /* Options. Leave them on. */
101 #ifndef DEBUG
102 #define DEBUG
103 #endif
104
105 extern const char *_res_opcodes[];
106
107 /*%
108 * Form all types of queries.
109 * Returns the size of the result or -1.
110 */
111 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)112 res_nmkquery(res_state statp,
113 int op, /*!< opcode of query */
114 const char *dname, /*!< domain name */
115 int class, int type, /*!< class and type of query */
116 const u_char *data, /*!< resource record data */
117 int datalen, /*!< length of data */
118 const u_char *newrr_in, /*!< new rr for modify or append */
119 u_char *buf, /*!< buffer to put query */
120 int buflen) /*!< size of buffer */
121 {
122 register HEADER *hp;
123 register u_char *cp, *ep;
124 register int n;
125 u_char *dnptrs[20], **dpp, **lastdnptr;
126
127 UNUSED(newrr_in);
128
129 #ifdef DEBUG
130 if (statp->options & RES_DEBUG)
131 printf(";; res_nmkquery(%s, %s, %s, %s)\n",
132 _res_opcodes[op], dname, p_class(class), p_type(type));
133 #endif
134 /*
135 * Initialize header fields.
136 */
137 if ((buf == NULL) || (buflen < HFIXEDSZ))
138 return (-1);
139 memset(buf, 0, HFIXEDSZ);
140 hp = (HEADER *)(void *)buf;
141 statp->id = res_nrandomid(statp);
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, (int)(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, (int)(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 _DIAGASSERT(__type_fit(int, cp - buf));
218 return (int)(cp - buf);
219 }
220
221 #ifdef RES_USE_EDNS0
222 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
223
224 int
res_nopt(res_state statp,int n0,u_char * buf,int buflen,int anslen)225 res_nopt(res_state statp,
226 int n0, /*%< current offset in buffer */
227 u_char *buf, /*%< buffer to put query */
228 int buflen, /*%< size of buffer */
229 int anslen) /*%< UDP answer buffer size */
230 {
231 register HEADER *hp;
232 register u_char *cp, *ep;
233 u_int16_t flags = 0;
234
235 #ifdef DEBUG
236 if ((statp->options & RES_DEBUG) != 0U)
237 printf(";; res_nopt()\n");
238 #endif
239
240 hp = (HEADER *)(void *)buf;
241 cp = buf + n0;
242 ep = buf + buflen;
243
244 if ((ep - cp) < 1 + RRFIXEDSZ)
245 return (-1);
246
247 *cp++ = 0; /*%< "." */
248 ns_put16(ns_t_opt, cp); /*%< TYPE */
249 cp += INT16SZ;
250 if (anslen > 0xffff)
251 anslen = 0xffff;
252 ns_put16(anslen, cp); /*%< CLASS = UDP payload size */
253 cp += INT16SZ;
254 *cp++ = NOERROR; /*%< extended RCODE */
255 *cp++ = 0; /*%< EDNS version */
256
257 if (statp->options & RES_USE_DNSSEC) {
258 #ifdef DEBUG
259 if (statp->options & RES_DEBUG)
260 printf(";; res_opt()... ENDS0 DNSSEC\n");
261 #endif
262 flags |= NS_OPT_DNSSEC_OK;
263 }
264 ns_put16(flags, cp);
265 cp += INT16SZ;
266
267 ns_put16(0U, cp); /*%< RDLEN */
268 cp += INT16SZ;
269
270 hp->arcount = htons(ntohs(hp->arcount) + 1);
271
272 _DIAGASSERT(__type_fit(int, cp - buf));
273 return (int)(cp - buf);
274 }
275
276 /*
277 * Construct variable data (RDATA) block for OPT psuedo-RR, append it
278 * to the buffer, then update the RDLEN field (previously set to zero by
279 * res_nopt()) with the new RDATA length.
280 */
281 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)282 res_nopt_rdata(res_state statp,
283 int n0, /*%< current offset in buffer */
284 u_char *buf, /*%< buffer to put query */
285 int buflen, /*%< size of buffer */
286 u_char *rdata, /*%< ptr to start of opt rdata */
287 u_short code, /*%< OPTION-CODE */
288 u_short len, /*%< OPTION-LENGTH */
289 u_char *data) /*%< OPTION_DATA */
290 {
291 register u_char *cp, *ep;
292
293 #ifdef DEBUG
294 if ((statp->options & RES_DEBUG) != 0U)
295 printf(";; res_nopt_rdata()\n");
296 #endif
297
298 cp = buf + n0;
299 ep = buf + buflen;
300
301 if ((ep - cp) < (4 + len))
302 return (-1);
303
304 if (rdata < (buf + 2) || rdata >= ep)
305 return (-1);
306
307 ns_put16(code, cp);
308 cp += INT16SZ;
309
310 ns_put16(len, cp);
311 cp += INT16SZ;
312
313 memcpy(cp, data, (size_t)len);
314 cp += len;
315
316 _DIAGASSERT(__type_fit(u_short, cp - rdata));
317 len = (u_short)(cp - rdata);
318 ns_put16(len, rdata - 2); /* Update RDLEN field */
319
320 _DIAGASSERT(__type_fit(int, cp - buf));
321 return (int)(cp - buf);
322 }
323 #endif
324
325 /*! \file */
326