Home | History | Annotate | Line # | Download | only in resolv
res_mkquery.c revision 1.10.4.2
      1 /*	$NetBSD: res_mkquery.c,v 1.10.4.2 2014/11/20 08:41:31 sborrill 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. All advertising materials mentioning features or use of this software
     33  *    must display the following acknowledgement:
     34  * 	This product includes software developed by the University of
     35  * 	California, Berkeley and its contributors.
     36  * 4. Neither the name of the University nor the names of its contributors
     37  *    may be used to endorse or promote products derived from this software
     38  *    without specific prior written permission.
     39  *
     40  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     50  * SUCH DAMAGE.
     51  */
     52 
     53 /*
     54  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
     55  *
     56  * Permission to use, copy, modify, and distribute this software for any
     57  * purpose with or without fee is hereby granted, provided that the above
     58  * copyright notice and this permission notice appear in all copies, and that
     59  * the name of Digital Equipment Corporation not be used in advertising or
     60  * publicity pertaining to distribution of the document or software without
     61  * specific, written prior permission.
     62  *
     63  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
     64  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
     65  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
     66  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
     67  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
     68  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
     69  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
     70  * 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 1.10 2008/12/11 09:59:00 marka Exp";
     78 #else
     79 __RCSID("$NetBSD: res_mkquery.c,v 1.10.4.2 2014/11/20 08:41:31 sborrill Exp $");
     80 #endif
     81 #endif /* LIBC_SCCS and not lint */
     82 
     83 #include "port_before.h"
     84 
     85 #include "namespace.h"
     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 #include <resolv.h>
     92 #include <stdio.h>
     93 #include <string.h>
     94 #include "port_after.h"
     95 
     96 #if 0
     97 #ifdef __weak_alias
     98 __weak_alias(res_nmkquery,_res_nmkquery)
     99 __weak_alias(res_nopt,_res_nopt)
    100 #endif
    101 #endif
    102 
    103 /* Options.  Leave them on. */
    104 #ifndef DEBUG
    105 #define DEBUG
    106 #endif
    107 
    108 extern const char *_res_opcodes[];
    109 
    110 /*%
    111  * Form all types of queries.
    112  * Returns the size of the result or -1.
    113  */
    114 int
    115 res_nmkquery(res_state statp,
    116 	     int op,			/*!< opcode of query  */
    117 	     const char *dname,		/*!< domain name  */
    118 	     int class, int type,	/*!< class and type of query  */
    119 	     const u_char *data,	/*!< resource record data  */
    120 	     int datalen,		/*!< length of data  */
    121 	     const u_char *newrr_in,	/*!< new rr for modify or append  */
    122 	     u_char *buf,		/*!< buffer to put query  */
    123 	     int buflen)		/*!< size of buffer  */
    124 {
    125 	register HEADER *hp;
    126 	register u_char *cp, *ep;
    127 	register int n;
    128 	u_char *dnptrs[20], **dpp, **lastdnptr;
    129 
    130 	UNUSED(newrr_in);
    131 
    132 #ifdef DEBUG
    133 	if (statp->options & RES_DEBUG)
    134 		printf(";; res_nmkquery(%s, %s, %s, %s)\n",
    135 		       _res_opcodes[op], dname, p_class(class), p_type(type));
    136 #endif
    137 	/*
    138 	 * Initialize header fields.
    139 	 */
    140 	if ((buf == NULL) || (buflen < HFIXEDSZ))
    141 		return (-1);
    142 	memset(buf, 0, HFIXEDSZ);
    143 	hp = (HEADER *)(void *)buf;
    144 	statp->id = res_nrandomid(statp);
    145 	hp->id = htons(statp->id);
    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 
    226 int
    227 res_nopt(res_state statp,
    228 	 int n0,		/*%< current offset in buffer */
    229 	 u_char *buf,		/*%< buffer to put query */
    230 	 int buflen,		/*%< size of buffer */
    231 	 int anslen)		/*%< UDP answer buffer size */
    232 {
    233 	register HEADER *hp;
    234 	register u_char *cp, *ep;
    235 	u_int16_t flags = 0;
    236 
    237 #ifdef DEBUG
    238 	if ((statp->options & RES_DEBUG) != 0U)
    239 		printf(";; res_nopt()\n");
    240 #endif
    241 
    242 	hp = (HEADER *)(void *)buf;
    243 	cp = buf + n0;
    244 	ep = buf + buflen;
    245 
    246 	if ((ep - cp) < 1 + RRFIXEDSZ)
    247 		return (-1);
    248 
    249 	*cp++ = 0;				/*%< "." */
    250 	ns_put16(ns_t_opt, cp);			/*%< TYPE */
    251 	cp += INT16SZ;
    252 	if (anslen > 0xffff)
    253 		anslen = 0xffff;
    254 	ns_put16(anslen, cp);			/*%< CLASS = UDP payload size */
    255 	cp += INT16SZ;
    256 	*cp++ = NOERROR;			/*%< extended RCODE */
    257 	*cp++ = 0;				/*%< EDNS version */
    258 
    259 	if (statp->options & RES_USE_DNSSEC) {
    260 #ifdef DEBUG
    261 		if (statp->options & RES_DEBUG)
    262 			printf(";; res_opt()... ENDS0 DNSSEC\n");
    263 #endif
    264 		flags |= NS_OPT_DNSSEC_OK;
    265 	}
    266 	ns_put16(flags, cp);
    267 	cp += INT16SZ;
    268 
    269 	ns_put16(0U, cp);			/*%< RDLEN */
    270 	cp += INT16SZ;
    271 
    272 	hp->arcount = htons(ntohs(hp->arcount) + 1);
    273 
    274 	return (cp - buf);
    275 }
    276 
    277 /*
    278  * Construct variable data (RDATA) block for OPT psuedo-RR, append it
    279  * to the buffer, then update the RDLEN field (previously set to zero by
    280  * res_nopt()) with the new RDATA length.
    281  */
    282 int
    283 res_nopt_rdata(res_state statp,
    284 	  int n0,	 	/*%< current offset in buffer */
    285 	  u_char *buf,	 	/*%< buffer to put query */
    286 	  int buflen,		/*%< size of buffer */
    287 	  u_char *rdata,	/*%< ptr to start of opt rdata */
    288 	  u_short code,		/*%< OPTION-CODE */
    289 	  u_short len,		/*%< OPTION-LENGTH */
    290 	  u_char *data)		/*%< OPTION_DATA */
    291 {
    292 	register u_char *cp, *ep;
    293 
    294 #ifdef DEBUG
    295 	if ((statp->options & RES_DEBUG) != 0U)
    296 		printf(";; res_nopt_rdata()\n");
    297 #endif
    298 
    299 	cp = buf + n0;
    300 	ep = buf + buflen;
    301 
    302 	if ((ep - cp) < (4 + len))
    303 		return (-1);
    304 
    305 	if (rdata < (buf + 2) || rdata >= ep)
    306 		return (-1);
    307 
    308 	ns_put16(code, cp);
    309 	cp += INT16SZ;
    310 
    311 	ns_put16(len, cp);
    312 	cp += INT16SZ;
    313 
    314 	memcpy(cp, data, (size_t)len);
    315 	cp += len;
    316 
    317 	len = cp - rdata;
    318 	ns_put16(len, rdata - 2);	/* Update RDLEN field */
    319 
    320 	return (cp - buf);
    321 }
    322 #endif
    323 
    324 /*! \file */
    325