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
76static const char sccsid[] = "@(#)res_mkquery.c	8.1 (Berkeley) 6/4/93";
77static 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
109extern const char *_res_opcodes[];
110
111/*
112 * Form all types of queries.
113 * Returns the size of the result or -1.
114 */
115int
116res_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->rcode = NOERROR;
149	cp = buf + HFIXEDSZ;
150	ep = buf + buflen;
151	dpp = dnptrs;
152	*dpp++ = buf;
153	*dpp++ = NULL;
154	lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
155	/*
156	 * perform opcode specific processing
157	 */
158	switch (op) {
159	case QUERY:	/*FALLTHROUGH*/
160	case NS_NOTIFY_OP:
161		if (ep - cp < QFIXEDSZ)
162			return (-1);
163		if ((n = dn_comp(dname, cp, ep - cp - QFIXEDSZ, dnptrs,
164		    lastdnptr)) < 0)
165			return (-1);
166		cp += n;
167		ns_put16(type, cp);
168		cp += INT16SZ;
169		ns_put16(class, cp);
170		cp += INT16SZ;
171		hp->qdcount = htons(1);
172		if (op == QUERY || data == NULL)
173			break;
174		/*
175		 * Make an additional record for completion domain.
176		 */
177		if ((ep - cp) < RRFIXEDSZ)
178			return (-1);
179		n = dn_comp((const char *)data, cp, ep - cp - RRFIXEDSZ,
180			    dnptrs, lastdnptr);
181		if (n < 0)
182			return (-1);
183		cp += n;
184		ns_put16(T_NULL, cp);
185		cp += INT16SZ;
186		ns_put16(class, cp);
187		cp += INT16SZ;
188		ns_put32(0, cp);
189		cp += INT32SZ;
190		ns_put16(0, cp);
191		cp += INT16SZ;
192		hp->arcount = htons(1);
193		break;
194
195	case IQUERY:
196		/*
197		 * Initialize answer section
198		 */
199		if (ep - cp < 1 + RRFIXEDSZ + datalen)
200			return (-1);
201		*cp++ = '\0';	/* no domain name */
202		ns_put16(type, cp);
203		cp += INT16SZ;
204		ns_put16(class, cp);
205		cp += INT16SZ;
206		ns_put32(0, cp);
207		cp += INT32SZ;
208		ns_put16(datalen, cp);
209		cp += INT16SZ;
210		if (datalen) {
211			memcpy(cp, data, (size_t)datalen);
212			cp += datalen;
213		}
214		hp->ancount = htons(1);
215		break;
216
217	default:
218		return (-1);
219	}
220	return (cp - buf);
221}
222
223#ifdef RES_USE_EDNS0
224/* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
225#ifndef T_OPT
226#define T_OPT	41
227#endif
228
229int
230res_nopt(res_state statp,
231	 int n0,		/* current offset in buffer */
232	 u_char *buf,		/* buffer to put query */
233	 int buflen,		/* size of buffer */
234	 int anslen)		/* UDP answer buffer size */
235{
236	register HEADER *hp;
237	register u_char *cp, *ep;
238	u_int16_t flags = 0;
239
240#ifdef DEBUG
241	if ((statp->options & RES_DEBUG) != 0U)
242		printf(";; res_nopt()\n");
243#endif
244
245	hp = (HEADER *)(void *)buf;
246	cp = buf + n0;
247	ep = buf + buflen;
248
249	if ((ep - cp) < 1 + RRFIXEDSZ)
250		return (-1);
251
252	*cp++ = 0;	/* "." */
253
254	ns_put16(T_OPT, cp);	/* TYPE */
255	cp += INT16SZ;
256	ns_put16(anslen & 0xffff, cp);	/* CLASS = UDP payload size */
257	cp += INT16SZ;
258	*cp++ = NOERROR;	/* extended RCODE */
259	*cp++ = 0;		/* EDNS version */
260	if (statp->options & RES_USE_DNSSEC) {
261#ifdef DEBUG
262		if (statp->options & RES_DEBUG)
263			printf(";; res_opt()... ENDS0 DNSSEC\n");
264#endif
265		flags |= NS_OPT_DNSSEC_OK;
266	}
267	ns_put16(flags, cp);
268	cp += INT16SZ;
269	ns_put16(0, cp);	/* RDLEN */
270	cp += INT16SZ;
271	hp->arcount = htons(ntohs(hp->arcount) + 1);
272
273	return (cp - buf);
274}
275#endif
276