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/* $OpenBSD: res_mkquery.c,v 1.10 2001/07/31 22:02:18 jakob Exp $ */
/*
* ++Copyright++ 1985, 1993
* -
* Copyright (c) 1985, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* -
* Portions Copyright (c) 1993 by Digital Equipment Corporation.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies, and that
* the name of Digital Equipment Corporation not be used in advertising or
* publicity pertaining to distribution of the document or software without
* specific, written prior permission.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
* WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
* CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
* -
* --Copyright--
*/
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)res_mkquery.c 8.1 (Berkeley) 6/4/93";
static char rcsid[] = "$From: res_mkquery.c,v 8.5 1996/08/27 08:33:28 vixie Exp $";
#else
static char rcsid[] = "$OpenBSD: res_mkquery.c,v 1.10 2001/07/31 22:02:18 jakob Exp $";
#endif
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/param.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <stdio.h>
#include <netdb.h>
#include <resolv.h>
#include <string.h>
/*
* Form all types of queries.
* Returns the size of the result or -1.
*/
/* ARGSUSED */
int
res_mkquery(op, dname, class, type, data, datalen, newrr_in, buf, buflen)
int op; /* opcode of query */
const char *dname; /* domain name */
int class, type; /* class and type of query */
const u_char *data; /* resource record data */
int datalen; /* length of data */
const u_char *newrr_in; /* new rr for modify or append */
u_char *buf; /* buffer to put query */
int buflen; /* size of buffer */
{
register HEADER *hp;
register u_char *cp;
register int n;
u_char *dnptrs[20], **dpp, **lastdnptr;
if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
h_errno = NETDB_INTERNAL;
return (-1);
}
#ifdef DEBUG
if (_res.options & RES_DEBUG)
printf(";; res_mkquery(%d, %s, %d, %d)\n",
op, dname, class, type);
#endif
/*
* Initialize header fields.
*
* A special random number generator is used to create non predictable
* and non repeating ids over a long period. It also avoids reuse
* by switching between two distinct number cycles.
*/
if ((buf == NULL) || (buflen < HFIXEDSZ))
return (-1);
bzero(buf, HFIXEDSZ);
hp = (HEADER *) buf;
_res.id = res_randomid();
hp->id = htons(_res.id);
hp->opcode = op;
hp->rd = (_res.options & RES_RECURSE) != 0;
hp->rcode = NOERROR;
cp = buf + HFIXEDSZ;
buflen -= HFIXEDSZ;
dpp = dnptrs;
*dpp++ = buf;
*dpp++ = NULL;
lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
/*
* perform opcode specific processing
*/
switch (op) {
case QUERY: /*FALLTHROUGH*/
case NS_NOTIFY_OP:
if ((buflen -= QFIXEDSZ) < 0)
return (-1);
if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
return (-1);
cp += n;
buflen -= n;
__putshort(type, cp);
cp += INT16SZ;
__putshort(class, cp);
cp += INT16SZ;
hp->qdcount = htons(1);
if (op == QUERY || data == NULL)
break;
/*
* Make an additional record for completion domain.
*/
buflen -= RRFIXEDSZ;
n = dn_comp((char *)data, cp, buflen, dnptrs, lastdnptr);
if (n < 0)
return (-1);
cp += n;
buflen -= n;
__putshort(T_NULL, cp);
cp += INT16SZ;
__putshort(class, cp);
cp += INT16SZ;
__putlong(0, cp);
cp += INT32SZ;
__putshort(0, cp);
cp += INT16SZ;
hp->arcount = htons(1);
break;
case IQUERY:
/*
* Initialize answer section
*/
if (buflen < 1 + RRFIXEDSZ + datalen)
return (-1);
*cp++ = '\0'; /* no domain name */
__putshort(type, cp);
cp += INT16SZ;
__putshort(class, cp);
cp += INT16SZ;
__putlong(0, cp);
cp += INT32SZ;
__putshort(datalen, cp);
cp += INT16SZ;
if (datalen) {
bcopy(data, cp, datalen);
cp += datalen;
}
hp->ancount = htons(1);
break;
default:
return (-1);
}
return (cp - buf);
}
/* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
int
res_opt(n0, buf, buflen, anslen)
int n0;
u_char *buf; /* buffer to put query */
int buflen; /* size of buffer */
int anslen; /* answer buffer length */
{
register HEADER *hp;
register u_char *cp;
hp = (HEADER *) buf;
cp = buf + n0;
buflen -= n0;
if (buflen < 1 + RRFIXEDSZ)
return -1;
*cp++ = 0; /* "." */
buflen--;
__putshort(T_OPT, cp); /* TYPE */
cp += INT16SZ;
__putshort(anslen & 0xffff, cp); /* CLASS = UDP payload size */
cp += INT16SZ;
*cp++ = NOERROR; /* extended RCODE */
*cp++ = 0; /* EDNS version */
if (_res.options & RES_USE_DNSSEC) {
#ifdef DEBUG
if (_res.options & RES_DEBUG)
printf(";; res_opt()... ENDS0 DNSSEC OK\n");
#endif /* DEBUG */
__putshort(DNS_MESSAGEEXTFLAG_DO, cp); /* EDNS Z field */
cp += INT16SZ;
} else {
__putshort(0, cp); /* EDNS Z field */
cp += INT16SZ;
}
__putshort(0, cp); /* RDLEN */
cp += INT16SZ;
hp->arcount = htons(ntohs(hp->arcount) + 1);
buflen -= RRFIXEDSZ;
return cp - buf;
}
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