/* $NetBSD: res_update.c,v 1.1.1.2 2012/09/09 16:08:08 christos Exp $ */
#if !defined(lint) && !defined(SABER)
static const char rcsid[] = "Id: res_update.c,v 1.13 2005/04/27 04:56:43 sra Exp ";
#endif /* not lint */
/*
* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* 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 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.
*/
/*! \file
* \brief
* Based on the Dynamic DNS reference implementation by Viraj Bais
* <
[email protected]>
*/
#include "port_before.h"
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <errno.h>
#include <limits.h>
#include <netdb.h>
#include <res_update.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <isc/list.h>
#include <resolv.h>
#include "port_after.h"
#include "res_private.h"
/*%
* Separate a linked list of records into groups so that all records
* in a group will belong to a single zone on the nameserver.
* Create a dynamic update packet for each zone and send it to the
* nameservers for that zone, and await answer.
* Abort if error occurs in updating any zone.
* Return the number of zones updated on success, < 0 on error.
*
* On error, caller must deal with the unsynchronized zones
* eg. an A record might have been successfully added to the forward
* zone but the corresponding PTR record would be missing if error
* was encountered while updating the reverse zone.
*/
struct zonegrp {
char z_origin[MAXDNAME];
ns_class z_class;
union res_sockaddr_union z_nsaddrs[MAXNS];
int z_nscount;
int z_flags;
LIST(ns_updrec) z_rrlist;
LINK(struct zonegrp) z_link;
};
#define ZG_F_ZONESECTADDED 0x0001
/* Forward. */
static void res_dprintf(const char *, ...) ISC_FORMAT_PRINTF(1, 2);
/* Macros. */
#define DPRINTF(x) do {\
int save_errno = errno; \
if ((statp->options & RES_DEBUG) != 0U) res_dprintf x; \
errno = save_errno; \
} while (0)
/* Public. */
int
res_nupdate(res_state statp, ns_updrec *rrecp_in, ns_tsig_key *key) {
ns_updrec *rrecp;
u_char answer[PACKETSZ];
u_char *packet;
struct zonegrp *zptr, tgrp;
LIST(struct zonegrp) zgrps;
int nzones = 0, nscount = 0, n;
union res_sockaddr_union nsaddrs[MAXNS];
packet = malloc(NS_MAXMSG);
if (packet == NULL) {
DPRINTF(("malloc failed"));
return (0);
}
/* Thread all of the updates onto a list of groups. */
INIT_LIST(zgrps);
memset(&tgrp, 0, sizeof (tgrp));
for (rrecp = rrecp_in; rrecp;
rrecp = LINKED(rrecp, r_link) ? NEXT(rrecp, r_link) : NULL) {
int nscnt;
/* Find the origin for it if there is one. */
tgrp.z_class = rrecp->r_class;
nscnt = res_findzonecut2(statp, rrecp->r_dname, tgrp.z_class,
RES_EXHAUSTIVE, tgrp.z_origin,
sizeof tgrp.z_origin,
tgrp.z_nsaddrs, MAXNS);
if (nscnt <= 0) {
DPRINTF(("res_findzonecut failed (%d)", nscnt));
goto done;
}
tgrp.z_nscount = nscnt;
/* Find the group for it if there is one. */
for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link))
if (ns_samename(tgrp.z_origin, zptr->z_origin) == 1 &&
tgrp.z_class == zptr->z_class)
break;
/* Make a group for it if there isn't one. */
if (zptr == NULL) {
zptr = malloc(sizeof *zptr);
if (zptr == NULL) {
DPRINTF(("malloc failed"));
goto done;
}
*zptr = tgrp;
zptr->z_flags = 0;
INIT_LINK(zptr, z_link);
INIT_LIST(zptr->z_rrlist);
APPEND(zgrps, zptr, z_link);
}
/* Thread this rrecp onto the right group. */
APPEND(zptr->z_rrlist, rrecp, r_glink);
}
for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) {
/* Construct zone section and prepend it. */
rrecp = res_mkupdrec(ns_s_zn, zptr->z_origin,
zptr->z_class, ns_t_soa, 0);
if (rrecp == NULL) {
DPRINTF(("res_mkupdrec failed"));
goto done;
}
PREPEND(zptr->z_rrlist, rrecp, r_glink);
zptr->z_flags |= ZG_F_ZONESECTADDED;
/* Marshall the update message. */
n = res_nmkupdate(statp, HEAD(zptr->z_rrlist),
packet, NS_MAXMSG);
DPRINTF(("res_mkupdate -> %d", n));
if (n < 0)
goto done;
/* Temporarily replace the resolver's nameserver set. */
nscount = res_getservers(statp, nsaddrs, MAXNS);
res_setservers(statp, zptr->z_nsaddrs, zptr->z_nscount);
/* Send the update and remember the result. */
if (key != NULL)
n = res_nsendsigned(statp, packet, n, key,
answer, sizeof answer);
else
n = res_nsend(statp, packet, n, answer, sizeof answer);
if (n < 0) {
DPRINTF(("res_nsend: send error, n=%d (%s)\n",
n, strerror(errno)));
goto done;
}
if (((HEADER *)answer)->rcode == NOERROR)
nzones++;
/* Restore resolver's nameserver set. */
res_setservers(statp, nsaddrs, nscount);
nscount = 0;
}
done:
while (!EMPTY(zgrps)) {
zptr = HEAD(zgrps);
if ((zptr->z_flags & ZG_F_ZONESECTADDED) != 0)
res_freeupdrec(HEAD(zptr->z_rrlist));
UNLINK(zgrps, zptr, z_link);
free(zptr);
}
if (nscount != 0)
res_setservers(statp, nsaddrs, nscount);
free(packet);
return (nzones);
}
/* Private. */
static void
res_dprintf(const char *fmt, ...) {
va_list ap;
va_start(ap, fmt);
fputs(";; res_nupdate: ", stderr);
vfprintf(stderr, fmt, ap);
fputc('\n', stderr);
va_end(ap);
}
