1 /* $NetBSD: res_mkquery.c,v 1.6 2006/01/24 17:40:32 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 1.1.2.2.4.2 2004/03/16 12:34:18 marka Exp";
78 #else
79 __RCSID("$NetBSD: res_mkquery.c,v 1.6 2006/01/24 17:40:32 christos Exp $");
80 #endif
81 #endif /* LIBC_SCCS and not lint */
82
83
84
85 #include <sys/types.h>
86 #include <sys/param.h>
87 #include <netinet/in.h>
88 #include <arpa/nameser.h>
89 #include <netdb.h>
90 #ifdef ANDROID_CHANGES
91 #include "resolv_private.h"
92 #else
93 #include <resolv.h>
94 #endif
95 #include <stdio.h>
96 #include <string.h>
97
98 /* Options. Leave them on. */
99 #ifndef DEBUG
100 #define DEBUG
101 #endif
102
103 #ifndef lint
104 #define UNUSED(a) (void)&a
105 #else
106 #define UNUSED(a) a = a
107 #endif
108
109 extern const char *_res_opcodes[];
110
111 /*
112 * Form all types of queries.
113 * Returns the size of the result or -1.
114 */
115 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)116 res_nmkquery(res_state statp,
117 int op, /* opcode of query */
118 const char *dname, /* domain name */
119 int class, int type, /* class and type of query */
120 const u_char *data, /* resource record data */
121 int datalen, /* length of data */
122 const u_char *newrr_in, /* new rr for modify or append */
123 u_char *buf, /* buffer to put query */
124 int buflen) /* size of buffer */
125 {
126 register HEADER *hp;
127 register u_char *cp, *ep;
128 register int n;
129 u_char *dnptrs[20], **dpp, **lastdnptr;
130
131 UNUSED(newrr_in);
132
133 #ifdef DEBUG
134 if (statp->options & RES_DEBUG)
135 printf(";; res_nmkquery(%s, %s, %s, %s)\n",
136 _res_opcodes[op], dname, p_class(class), p_type(type));
137 #endif
138 /*
139 * Initialize header fields.
140 */
141 if ((buf == NULL) || (buflen < HFIXEDSZ))
142 return (-1);
143 memset(buf, 0, HFIXEDSZ);
144 hp = (HEADER *)(void *)buf;
145 hp->id = htons(res_randomid());
146 hp->opcode = op;
147 hp->rd = (statp->options & RES_RECURSE) != 0U;
148 hp->ad = (statp->options & RES_USE_DNSSEC) != 0U;
149 hp->rcode = NOERROR;
150 cp = buf + HFIXEDSZ;
151 ep = buf + buflen;
152 dpp = dnptrs;
153 *dpp++ = buf;
154 *dpp++ = NULL;
155 lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
156 /*
157 * perform opcode specific processing
158 */
159 switch (op) {
160 case QUERY: /*FALLTHROUGH*/
161 case NS_NOTIFY_OP:
162 if (ep - cp < QFIXEDSZ)
163 return (-1);
164 if ((n = dn_comp(dname, cp, ep - cp - QFIXEDSZ, dnptrs,
165 lastdnptr)) < 0)
166 return (-1);
167 cp += n;
168 ns_put16(type, cp);
169 cp += INT16SZ;
170 ns_put16(class, cp);
171 cp += INT16SZ;
172 hp->qdcount = htons(1);
173 if (op == QUERY || data == NULL)
174 break;
175 /*
176 * Make an additional record for completion domain.
177 */
178 if ((ep - cp) < RRFIXEDSZ)
179 return (-1);
180 n = dn_comp((const char *)data, cp, ep - cp - RRFIXEDSZ,
181 dnptrs, lastdnptr);
182 if (n < 0)
183 return (-1);
184 cp += n;
185 ns_put16(T_NULL, cp);
186 cp += INT16SZ;
187 ns_put16(class, cp);
188 cp += INT16SZ;
189 ns_put32(0, cp);
190 cp += INT32SZ;
191 ns_put16(0, cp);
192 cp += INT16SZ;
193 hp->arcount = htons(1);
194 break;
195
196 case IQUERY:
197 /*
198 * Initialize answer section
199 */
200 if (ep - cp < 1 + RRFIXEDSZ + datalen)
201 return (-1);
202 *cp++ = '\0'; /* no domain name */
203 ns_put16(type, cp);
204 cp += INT16SZ;
205 ns_put16(class, cp);
206 cp += INT16SZ;
207 ns_put32(0, cp);
208 cp += INT32SZ;
209 ns_put16(datalen, cp);
210 cp += INT16SZ;
211 if (datalen) {
212 memcpy(cp, data, (size_t)datalen);
213 cp += datalen;
214 }
215 hp->ancount = htons(1);
216 break;
217
218 default:
219 return (-1);
220 }
221 return (cp - buf);
222 }
223
224 #ifdef RES_USE_EDNS0
225 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
226 #ifndef T_OPT
227 #define T_OPT 41
228 #endif
229
230 int
res_nopt(res_state statp,int n0,u_char * buf,int buflen,int anslen)231 res_nopt(res_state statp,
232 int n0, /* current offset in buffer */
233 u_char *buf, /* buffer to put query */
234 int buflen, /* size of buffer */
235 int anslen) /* UDP answer buffer size */
236 {
237 register HEADER *hp;
238 register u_char *cp, *ep;
239 u_int16_t flags = 0;
240
241 #ifdef DEBUG
242 if ((statp->options & RES_DEBUG) != 0U)
243 printf(";; res_nopt()\n");
244 #endif
245
246 hp = (HEADER *)(void *)buf;
247 cp = buf + n0;
248 ep = buf + buflen;
249
250 if ((ep - cp) < 1 + RRFIXEDSZ)
251 return (-1);
252
253 *cp++ = 0; /* "." */
254
255 ns_put16(T_OPT, cp); /* TYPE */
256 cp += INT16SZ;
257 if (anslen > 0xffff)
258 anslen = 0xffff;
259 ns_put16(anslen, cp); /* CLASS = UDP payload size */
260 cp += INT16SZ;
261 *cp++ = NOERROR; /* extended RCODE */
262 *cp++ = 0; /* EDNS version */
263 if (statp->options & RES_USE_DNSSEC) {
264 #ifdef DEBUG
265 if (statp->options & RES_DEBUG)
266 printf(";; res_opt()... ENDS0 DNSSEC\n");
267 #endif
268 flags |= NS_OPT_DNSSEC_OK;
269 }
270 ns_put16(flags, cp);
271 cp += INT16SZ;
272 #ifdef EDNS0_PADDING
273 {
274 u_int16_t minlen = (cp - buf) + 3 * INT16SZ;
275 u_int16_t extra = minlen % EDNS0_PADDING;
276 u_int16_t padlen = (EDNS0_PADDING - extra) % EDNS0_PADDING;
277 if (minlen > buflen) {
278 return (-1);
279 }
280 padlen = MIN(padlen, buflen - minlen);
281 ns_put16(padlen + 2 * INT16SZ, cp); /* RDLEN */
282 cp += INT16SZ;
283 ns_put16(NS_OPT_PADDING, cp); /* OPTION-CODE */
284 cp += INT16SZ;
285 ns_put16(padlen, cp); /* OPTION-LENGTH */
286 cp += INT16SZ;
287 memset(cp, 0, padlen);
288 cp += padlen;
289 }
290 #else
291 ns_put16(0, cp); /* RDLEN */
292 cp += INT16SZ;
293 #endif
294 hp->arcount = htons(ntohs(hp->arcount) + 1);
295
296 return (cp - buf);
297 }
298 #endif
299