glibc/resolv/res_mkquery.c
Ulrich Drepper 2bbb7d5b3c * resolv/res_init.c (res_setoptions): Recognize edns0 option.
* resolv/res_mkquery.c: Define __res_nopt.
	* resolv/res_query.c (__libc_res_nquery): If RES_USE_EDNS0 is set
	try adding EDNS0 record.
	* resolv/res_send.c (send_dg): If request failed with FORMERR and
	EDNS0 record was send make sure we don't try it again.
	* resolv/resolv.h: Define RES_F_EDNS0ERR and RES_USE_EDNS0.
	* include/resolv.h: Declare __res_nopt.
2007-02-09 23:46:29 +00:00

257 lines
7.9 KiB
C

/*
* 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.
* 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.
*/
/*
* Portions Copyright (c) 1996-1999 by Internet Software Consortium.
*
* 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.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
* ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
* CONSORTIUM 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static const char sccsid[] = "@(#)res_mkquery.c 8.1 (Berkeley) 6/4/93";
static const char rcsid[] = "$BINDId: res_mkquery.c,v 8.12 1999/10/13 16:39:40 vixie Exp $";
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/param.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <netdb.h>
#include <resolv.h>
#include <stdio.h>
#include <string.h>
/* Options. Leave them on. */
/* #define DEBUG */
#ifdef _LIBC
# include <hp-timing.h>
# if HP_TIMING_AVAIL
# define RANDOM_BITS(Var) { uint64_t v64; HP_TIMING_NOW (v64); Var = v64; }
# endif
#endif
/*
* Form all types of queries.
* Returns the size of the result or -1.
*/
int
res_nmkquery(res_state statp,
int op, /* opcode of query */
const char *dname, /* domain name */
int class, int 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;
#ifdef DEBUG
if (statp->options & RES_DEBUG)
printf(";; res_nmkquery(%s, %s, %s, %s)\n",
_res_opcodes[op], dname, p_class(class), p_type(type));
#endif
/*
* Initialize header fields.
*/
if ((buf == NULL) || (buflen < HFIXEDSZ))
return (-1);
memset(buf, 0, HFIXEDSZ);
hp = (HEADER *) buf;
/* We randomize the IDs every time. The old code just
incremented by one after the initial randomization which
still predictable if the application does multiple
requests. */
int randombits;
do
{
#ifdef RANDOM_BITS
RANDOM_BITS (randombits);
#else
struct timeval tv;
__gettimeofday (&tv, NULL);
randombits = (tv.tv_sec << 8) ^ tv.tv_usec;
#endif
}
while ((randombits & 0xffff) == 0);
statp->id = (statp->id + randombits) & 0xffff;
hp->id = statp->id;
hp->opcode = op;
hp->rd = (statp->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 NS_NOTIFY_OP:
if ((buflen -= QFIXEDSZ + (data == NULL ? 0 : RRFIXEDSZ)) < 0)
return (-1);
goto compose;
case QUERY:
if ((buflen -= QFIXEDSZ) < 0)
return (-1);
compose:
if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
return (-1);
cp += n;
buflen -= n;
NS_PUT16 (type, cp);
NS_PUT16 (class, cp);
hp->qdcount = htons(1);
if (op == QUERY || data == NULL)
break;
/*
* Make an additional record for completion domain.
*/
n = dn_comp((char *)data, cp, buflen, dnptrs, lastdnptr);
if (__builtin_expect (n < 0, 0))
return (-1);
cp += n;
buflen -= n;
NS_PUT16 (T_NULL, cp);
NS_PUT16 (class, cp);
NS_PUT32 (0, cp);
NS_PUT16 (0, cp);
hp->arcount = htons(1);
break;
case IQUERY:
/*
* Initialize answer section
*/
if (__builtin_expect (buflen < 1 + RRFIXEDSZ + datalen, 0))
return (-1);
*cp++ = '\0'; /* no domain name */
NS_PUT16 (type, cp);
NS_PUT16 (class, cp);
NS_PUT32 (0, cp);
NS_PUT16 (datalen, cp);
if (datalen) {
memcpy(cp, data, datalen);
cp += datalen;
}
hp->ancount = htons(1);
break;
default:
return (-1);
}
return (cp - buf);
}
libresolv_hidden_def (res_nmkquery)
/* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
#ifndef T_OPT
#define T_OPT 41
#endif
int
__res_nopt(res_state statp,
int n0, /* current offset in buffer */
u_char *buf, /* buffer to put query */
int buflen, /* size of buffer */
int anslen) /* UDP answer buffer size */
{
u_int16_t flags = 0;
#ifdef DEBUG
if ((statp->options & RES_DEBUG) != 0U)
printf(";; res_nopt()\n");
#endif
HEADER *hp = (HEADER *) buf;
u_char *cp = buf + n0;
u_char *ep = buf + buflen;
if ((ep - cp) < 1 + RRFIXEDSZ)
return -1;
*cp++ = 0; /* "." */
ns_put16(T_OPT, cp); /* TYPE */
cp += INT16SZ;
ns_put16(anslen & 0xffff, cp); /* CLASS = UDP payload size */
cp += INT16SZ;
*cp++ = NOERROR; /* extended RCODE */
*cp++ = 0; /* EDNS version */
/* XXX Once we support DNSSEC we change the flag value here. */
ns_put16(flags, cp);
cp += INT16SZ;
ns_put16(0, cp); /* RDLEN */
cp += INT16SZ;
hp->arcount = htons(ntohs(hp->arcount) + 1);
return cp - buf;
}
libresolv_hidden_def (__res_nopt)