xref: /freebsd/lib/libc/resolv/res_mkquery.c (revision d056fa046c6a91b90cd98165face0e42a33a5173)
1 /*
2  * Copyright (c) 1985, 1993
3  *    The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  * 	This product includes software developed by the University of
16  * 	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 /*
35  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
36  *
37  * Permission to use, copy, modify, and distribute this software for any
38  * purpose with or without fee is hereby granted, provided that the above
39  * copyright notice and this permission notice appear in all copies, and that
40  * the name of Digital Equipment Corporation not be used in advertising or
41  * publicity pertaining to distribution of the document or software without
42  * specific, written prior permission.
43  *
44  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
45  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
46  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
47  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
48  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
49  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
50  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
51  * SOFTWARE.
52  */
53 
54 /*
55  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
56  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
57  *
58  * Permission to use, copy, modify, and distribute this software for any
59  * purpose with or without fee is hereby granted, provided that the above
60  * copyright notice and this permission notice appear in all copies.
61  *
62  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
63  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
64  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
65  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
66  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
67  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
68  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
69  */
70 
71 #if defined(LIBC_SCCS) && !defined(lint)
72 static const char sccsid[] = "@(#)res_mkquery.c	8.1 (Berkeley) 6/4/93";
73 static const char rcsid[] = "$Id: res_mkquery.c,v 1.1.2.2.4.2 2004/03/16 12:34:18 marka Exp $";
74 #endif /* LIBC_SCCS and not lint */
75 #include <sys/cdefs.h>
76 __FBSDID("$FreeBSD$");
77 
78 #include "port_before.h"
79 #include <sys/types.h>
80 #include <sys/param.h>
81 #include <netinet/in.h>
82 #include <arpa/nameser.h>
83 #include <netdb.h>
84 #include <resolv.h>
85 #include <stdio.h>
86 #include <string.h>
87 #include "port_after.h"
88 
89 /* Options.  Leave them on. */
90 #define DEBUG
91 
92 extern const char *_res_opcodes[];
93 
94 /*
95  * Form all types of queries.
96  * Returns the size of the result or -1.
97  */
98 int
99 res_nmkquery(res_state statp,
100 	     int op,			/* opcode of query */
101 	     const char *dname,		/* domain name */
102 	     int class, int type,	/* class and type of query */
103 	     const u_char *data,	/* resource record data */
104 	     int datalen,		/* length of data */
105 	     const u_char *newrr_in,	/* new rr for modify or append */
106 	     u_char *buf,		/* buffer to put query */
107 	     int buflen)		/* size of buffer */
108 {
109 	HEADER *hp;
110 	u_char *cp, *ep;
111 	int n;
112 	u_char *dnptrs[20], **dpp, **lastdnptr;
113 
114 	UNUSED(newrr_in);
115 
116 #ifdef DEBUG
117 	if (statp->options & RES_DEBUG)
118 		printf(";; res_nmkquery(%s, %s, %s, %s)\n",
119 		       _res_opcodes[op], dname, p_class(class), p_type(type));
120 #endif
121 	/*
122 	 * Initialize header fields.
123 	 */
124 	if ((buf == NULL) || (buflen < HFIXEDSZ))
125 		return (-1);
126 	memset(buf, 0, HFIXEDSZ);
127 	hp = (HEADER *) buf;
128 	hp->id = htons(++statp->id);
129 	hp->opcode = op;
130 	hp->rd = (statp->options & RES_RECURSE) != 0U;
131 	hp->rcode = NOERROR;
132 	cp = buf + HFIXEDSZ;
133 	ep = buf + buflen;
134 	dpp = dnptrs;
135 	*dpp++ = buf;
136 	*dpp++ = NULL;
137 	lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
138 	/*
139 	 * perform opcode specific processing
140 	 */
141 	switch (op) {
142 	case QUERY:	/*FALLTHROUGH*/
143 	case NS_NOTIFY_OP:
144 		if (ep - cp < QFIXEDSZ)
145 			return (-1);
146 		if ((n = dn_comp(dname, cp, ep - cp - QFIXEDSZ, dnptrs,
147 		    lastdnptr)) < 0)
148 			return (-1);
149 		cp += n;
150 		ns_put16(type, cp);
151 		cp += INT16SZ;
152 		ns_put16(class, cp);
153 		cp += INT16SZ;
154 		hp->qdcount = htons(1);
155 		if (op == QUERY || data == NULL)
156 			break;
157 		/*
158 		 * Make an additional record for completion domain.
159 		 */
160 		if ((ep - cp) < RRFIXEDSZ)
161 			return (-1);
162 		n = dn_comp((const char *)data, cp, ep - cp - RRFIXEDSZ,
163 			    dnptrs, lastdnptr);
164 		if (n < 0)
165 			return (-1);
166 		cp += n;
167 		ns_put16(T_NULL, cp);
168 		cp += INT16SZ;
169 		ns_put16(class, cp);
170 		cp += INT16SZ;
171 		ns_put32(0, cp);
172 		cp += INT32SZ;
173 		ns_put16(0, cp);
174 		cp += INT16SZ;
175 		hp->arcount = htons(1);
176 		break;
177 
178 	case IQUERY:
179 		/*
180 		 * Initialize answer section
181 		 */
182 		if (ep - cp < 1 + RRFIXEDSZ + datalen)
183 			return (-1);
184 		*cp++ = '\0';	/* no domain name */
185 		ns_put16(type, cp);
186 		cp += INT16SZ;
187 		ns_put16(class, cp);
188 		cp += INT16SZ;
189 		ns_put32(0, cp);
190 		cp += INT32SZ;
191 		ns_put16(datalen, cp);
192 		cp += INT16SZ;
193 		if (datalen) {
194 			memcpy(cp, data, datalen);
195 			cp += datalen;
196 		}
197 		hp->ancount = htons(1);
198 		break;
199 
200 	default:
201 		return (-1);
202 	}
203 	return (cp - buf);
204 }
205 
206 #ifdef RES_USE_EDNS0
207 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
208 #ifndef T_OPT
209 #define T_OPT	41
210 #endif
211 
212 int
213 res_nopt(res_state statp,
214 	 int n0,		/* current offset in buffer */
215 	 u_char *buf,		/* buffer to put query */
216 	 int buflen,		/* size of buffer */
217 	 int anslen)		/* UDP answer buffer size */
218 {
219 	HEADER *hp;
220 	u_char *cp, *ep;
221 	u_int16_t flags = 0;
222 
223 #ifdef DEBUG
224 	if ((statp->options & RES_DEBUG) != 0U)
225 		printf(";; res_nopt()\n");
226 #endif
227 
228 	hp = (HEADER *) buf;
229 	cp = buf + n0;
230 	ep = buf + buflen;
231 
232 	if ((ep - cp) < 1 + RRFIXEDSZ)
233 		return (-1);
234 
235 	*cp++ = 0;	/* "." */
236 
237 	ns_put16(T_OPT, cp);	/* TYPE */
238 	cp += INT16SZ;
239 	if (anslen > 0xffff)
240 		anslen = 0xffff;		/* limit to 16bit value */
241 	ns_put16(anslen & 0xffff, cp);	/* CLASS = UDP payload size */
242 	cp += INT16SZ;
243 	*cp++ = NOERROR;	/* extended RCODE */
244 	*cp++ = 0;		/* EDNS version */
245 	if (statp->options & RES_USE_DNSSEC) {
246 #ifdef DEBUG
247 		if (statp->options & RES_DEBUG)
248 			printf(";; res_opt()... ENDS0 DNSSEC\n");
249 #endif
250 		flags |= NS_OPT_DNSSEC_OK;
251 	}
252 	ns_put16(flags, cp);
253 	cp += INT16SZ;
254 	ns_put16(0, cp);	/* RDLEN */
255 	cp += INT16SZ;
256 	hp->arcount = htons(ntohs(hp->arcount) + 1);
257 
258 	return (cp - buf);
259 }
260 #endif
261