1 /* $NetBSD: res_mkquery.c,v 1.6 2006/01/24 17:40:32 christos Exp $ */
2
3 /*
4 * Copyright (c) 2008 Android Open Source Project (query id randomization)
5 * Copyright (c) 1985, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37 /*
38 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
39 *
40 * Permission to use, copy, modify, and distribute this software for any
41 * purpose with or without fee is hereby granted, provided that the above
42 * copyright notice and this permission notice appear in all copies, and that
43 * the name of Digital Equipment Corporation not be used in advertising or
44 * publicity pertaining to distribution of the document or software without
45 * specific, written prior permission.
46 *
47 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
48 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
49 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
50 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
51 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
52 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
53 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
54 * SOFTWARE.
55 */
56
57 /*
58 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
59 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
60 *
61 * Permission to use, copy, modify, and distribute this software for any
62 * purpose with or without fee is hereby granted, provided that the above
63 * copyright notice and this permission notice appear in all copies.
64 *
65 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
66 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
67 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
68 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
69 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
70 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
71 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
72 */
73
74 #include <sys/cdefs.h>
75 #if defined(LIBC_SCCS) && !defined(lint)
76 #ifdef notdef
77 static const char sccsid[] = "@(#)res_mkquery.c 8.1 (Berkeley) 6/4/93";
78 static const char rcsid[] = "Id: res_mkquery.c,v 1.1.2.2.4.2 2004/03/16 12:34:18 marka Exp";
79 #else
80 __RCSID("$NetBSD: res_mkquery.c,v 1.6 2006/01/24 17:40:32 christos Exp $");
81 #endif
82 #endif /* LIBC_SCCS and not lint */
83
84
85
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 #ifdef ANDROID_CHANGES
92 #include "resolv_private.h"
93 #else
94 #include <resolv.h>
95 #endif
96 #include <stdio.h>
97 #include <string.h>
98
99 /* Options. Leave them on. */
100 #ifndef DEBUG
101 #define DEBUG
102 #endif
103
104 #ifndef lint
105 #define UNUSED(a) (void)&a
106 #else
107 #define UNUSED(a) a = a
108 #endif
109
110 extern const char *_res_opcodes[];
111
112 /*
113 * Form all types of queries.
114 * Returns the size of the result or -1.
115 */
116 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)117 res_nmkquery(res_state statp,
118 int op, /* opcode of query */
119 const char *dname, /* domain name */
120 int class, int type, /* class and type of query */
121 const u_char *data, /* resource record data */
122 int datalen, /* length of data */
123 const u_char *newrr_in, /* new rr for modify or append */
124 u_char *buf, /* buffer to put query */
125 int buflen) /* size of buffer */
126 {
127 register HEADER *hp;
128 register u_char *cp, *ep;
129 register int n;
130 u_char *dnptrs[20], **dpp, **lastdnptr;
131
132 UNUSED(newrr_in);
133
134 #ifdef DEBUG
135 if (statp->options & RES_DEBUG)
136 printf(";; res_nmkquery(%s, %s, %s, %s)\n",
137 _res_opcodes[op], dname, p_class(class), p_type(type));
138 #endif
139 /*
140 * Initialize header fields.
141 */
142 if ((buf == NULL) || (buflen < HFIXEDSZ))
143 return (-1);
144 memset(buf, 0, HFIXEDSZ);
145 hp = (HEADER *)(void *)buf;
146 hp->id = htons(res_randomid());
147 hp->opcode = op;
148 hp->rd = (statp->options & RES_RECURSE) != 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 ns_put16(anslen & 0xffff, cp); /* CLASS = UDP payload size */
258 cp += INT16SZ;
259 *cp++ = NOERROR; /* extended RCODE */
260 *cp++ = 0; /* EDNS version */
261 if (statp->options & RES_USE_DNSSEC) {
262 #ifdef DEBUG
263 if (statp->options & RES_DEBUG)
264 printf(";; res_opt()... ENDS0 DNSSEC\n");
265 #endif
266 flags |= NS_OPT_DNSSEC_OK;
267 }
268 ns_put16(flags, cp);
269 cp += INT16SZ;
270 ns_put16(0, cp); /* RDLEN */
271 cp += INT16SZ;
272 hp->arcount = htons(ntohs(hp->arcount) + 1);
273
274 return (cp - buf);
275 }
276 #endif
277