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/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Copyright (C) 2009 Internet Systems Consortium, Inc. ("ISC")
*
* Permission to use, copy, modify, and/or 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 ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC 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.
*/
#include "port_before.h"
#if __OpenBSD__
#include <sys/types.h>
#endif
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <errno.h>
#include <resolv_joy.h>
#include <string.h>
#include "port_after.h"
#define CONSUME_SRC \
do { \
rdata += n, rdlen -= n; \
} while (0)
#define CONSUME_DST \
do { \
nrdata += n, nrdsiz -= n, nrdlen += n; \
} while (0)
#define UNPACK_DNAME \
do { \
size_t t; \
\
if ((n = ns_name_unpack2(msg,eom,rdata,nrdata,nrdsiz,&t))<0) {\
errno = EMSGSIZE; \
return (-1); \
} \
CONSUME_SRC; \
n = t; \
CONSUME_DST; \
} while (0)
#define UNPACK_SOME(x) \
do { \
n = (x); \
if ((size_t)n > rdlen || (size_t)n > nrdsiz) { \
errno = EMSGSIZE; \
return (-1); \
} \
memcpy(nrdata, rdata, n); \
CONSUME_SRC; CONSUME_DST; \
} while (0)
#define UNPACK_REST(x) \
do { \
n = (x); \
if ((size_t)n != rdlen) { \
errno = EMSGSIZE; \
return (-1); \
} \
memcpy(nrdata, rdata, n); \
CONSUME_SRC; CONSUME_DST; \
} while (0)
ssize_t
ns_rdata_unpack(const u_char *msg, const u_char *eom,
ns_type type, const u_char *rdata, size_t rdlen,
u_char *nrdata, size_t nrdsiz)
{
size_t nrdlen = 0;
int n;
switch (type) {
case ns_t_a:
UNPACK_REST(NS_INADDRSZ);
break;
case ns_t_aaaa:
UNPACK_REST(NS_IN6ADDRSZ);
break;
case ns_t_cname:
case ns_t_mb:
case ns_t_mg:
case ns_t_mr:
case ns_t_ns:
case ns_t_ptr:
case ns_t_dname:
UNPACK_DNAME;
break;
case ns_t_soa:
UNPACK_DNAME;
UNPACK_DNAME;
UNPACK_SOME(NS_INT32SZ * 5);
break;
case ns_t_mx:
case ns_t_afsdb:
case ns_t_rt:
UNPACK_SOME(NS_INT16SZ);
UNPACK_DNAME;
break;
case ns_t_px:
UNPACK_SOME(NS_INT16SZ);
UNPACK_DNAME;
UNPACK_DNAME;
break;
case ns_t_srv:
UNPACK_SOME(NS_INT16SZ * 3);
UNPACK_DNAME;
break;
case ns_t_minfo:
case ns_t_rp:
UNPACK_DNAME;
UNPACK_DNAME;
break;
default:
UNPACK_SOME(rdlen);
break;
}
if (rdlen > 0) {
errno = EMSGSIZE;
return (-1);
}
return (nrdlen);
}
#define EQUAL_CONSUME \
do { \
rdata1 += n, rdlen1 -= n; \
rdata2 += n, rdlen2 -= n; \
} while (0)
#define EQUAL_DNAME \
do { \
ssize_t n; \
\
if (rdlen1 != rdlen2) \
return (0); \
n = ns_name_eq(rdata1, rdlen1, rdata2, rdlen2); \
if (n <= 0) \
return (n); \
n = rdlen1; \
EQUAL_CONSUME; \
} while (0)
#define EQUAL_SOME(x) \
do { \
size_t n = (x); \
\
if (n > rdlen1 || n > rdlen2) { \
errno = EMSGSIZE; \
return (-1); \
} \
if (memcmp(rdata1, rdata2, n) != 0) \
return (0); \
EQUAL_CONSUME; \
} while (0)
int
ns_rdata_equal(ns_type type,
const u_char *rdata1, size_t rdlen1,
const u_char *rdata2, size_t rdlen2)
{
switch (type) {
case ns_t_cname:
case ns_t_mb:
case ns_t_mg:
case ns_t_mr:
case ns_t_ns:
case ns_t_ptr:
case ns_t_dname:
EQUAL_DNAME;
break;
case ns_t_soa:
/* "There can be only one." --Highlander */
break;
case ns_t_mx:
case ns_t_afsdb:
case ns_t_rt:
EQUAL_SOME(NS_INT16SZ);
EQUAL_DNAME;
break;
case ns_t_px:
EQUAL_SOME(NS_INT16SZ);
EQUAL_DNAME;
EQUAL_DNAME;
break;
case ns_t_srv:
EQUAL_SOME(NS_INT16SZ * 3);
EQUAL_DNAME;
break;
case ns_t_minfo:
case ns_t_rp:
EQUAL_DNAME;
EQUAL_DNAME;
break;
default:
EQUAL_SOME(rdlen1);
break;
}
if (rdlen1 != 0 || rdlen2 != 0)
return (0);
return (1);
}
#define REFERS_DNAME \
do { \
int n; \
\
n = ns_name_eq(rdata, rdlen, nname, NS_MAXNNAME); \
if (n < 0) \
return (-1); \
if (n > 0) \
return (1); \
n = dn_skipname(rdata, rdata + rdlen); \
if (n < 0) \
return (-1); \
CONSUME_SRC; \
} while (0)
#define REFERS_SOME(x) \
do { \
size_t n = (x); \
\
if (n > rdlen) { \
errno = EMSGSIZE; \
return (-1); \
} \
CONSUME_SRC; \
} while (0)
int
ns_rdata_refers(ns_type type,
const u_char *rdata, size_t rdlen,
const u_char *nname)
{
switch (type) {
case ns_t_cname:
case ns_t_mb:
case ns_t_mg:
case ns_t_mr:
case ns_t_ns:
case ns_t_ptr:
case ns_t_dname:
REFERS_DNAME;
break;
case ns_t_soa:
REFERS_DNAME;
REFERS_DNAME;
REFERS_SOME(NS_INT32SZ * 5);
break;
case ns_t_mx:
case ns_t_afsdb:
case ns_t_rt:
REFERS_SOME(NS_INT16SZ);
REFERS_DNAME;
break;
case ns_t_px:
REFERS_SOME(NS_INT16SZ);
REFERS_DNAME;
REFERS_DNAME;
break;
case ns_t_srv:
REFERS_SOME(NS_INT16SZ * 3);
REFERS_DNAME;
break;
case ns_t_minfo:
case ns_t_rp:
REFERS_DNAME;
REFERS_DNAME;
break;
default:
REFERS_SOME(rdlen);
break;
}
if (rdlen != 0) {
errno = EMSGSIZE;
return (-1);
}
return (0);
}
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