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#if !defined(lint) && !defined(SABER)
static const char rcsid[] = "$Id: res_update.c,v 1.11.2.2 2001/06/08 23:12:45 mellon Exp $";
#endif /* not lint */
/*
* 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.
*/
/*
* Based on the Dynamic DNS reference implementation by Viraj Bais
* <viraj_bais@ccm.fm.intel.com>
*/
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <limits.h>
#include <netdb.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <isc-dhcp/list.h>
#include "minires/minires.h"
#include "arpa/nameser.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;
struct in_addr z_nsaddrs[MAXNS];
int z_nscount;
int z_flags;
ISC_LIST(ns_updrec) z_rrlist;
ISC_LINK(struct zonegrp) z_link;
};
#define ZG_F_ZONESECTADDED 0x0001
/* Forward. */
static int nscopy(struct sockaddr_in *, const struct sockaddr_in *, int);
static int nsprom(struct sockaddr_in *, const struct in_addr *, int);
void tkey_free (ns_tsig_key **);
isc_result_t
res_nupdate(res_state statp, ns_updrec *rrecp_in) {
ns_updrec *rrecp;
double answer[PACKETSZ / sizeof (double)];
double packet[2*PACKETSZ / sizeof (double)];
struct zonegrp *zptr, tgrp;
int nzones = 0, nscount = 0;
unsigned n;
unsigned rval;
struct sockaddr_in nsaddrs[MAXNS];
ns_tsig_key *key;
void *zcookie = 0;
void *zcookp = &zcookie;
isc_result_t rcode;
again:
/* Make sure all the updates are in the same zone, and find out
what zone they are in. */
zptr = NULL;
for (rrecp = rrecp_in; rrecp; rrecp = ISC_LIST_NEXT(rrecp, r_link)) {
/* Find the origin for it if there is one. */
tgrp.z_class = rrecp->r_class;
rcode = res_findzonecut(statp, rrecp->r_dname, tgrp.z_class,
RES_EXHAUSTIVE,
tgrp.z_origin,
sizeof tgrp.z_origin,
tgrp.z_nsaddrs, MAXNS, &tgrp.z_nscount,
zcookp);
if (rcode != ISC_R_SUCCESS)
goto done;
if (tgrp.z_nscount <= 0) {
rcode = ISC_R_NOTZONE;
goto done;
}
/* Make a group for it if there isn't one. */
if (zptr == NULL) {
zptr = malloc(sizeof *zptr);
if (zptr == NULL) {
rcode = ISC_R_NOMEMORY;
goto done;
}
*zptr = tgrp;
zptr->z_flags = 0;
ISC_LIST_INIT(zptr->z_rrlist);
} else if (ns_samename(tgrp.z_origin, zptr->z_origin) == 0 ||
tgrp.z_class != zptr->z_class) {
/* Some of the records are in different zones. */
rcode = ISC_R_CROSSZONE;
goto done;
}
/* Thread this rrecp onto the zone group. */
ISC_LIST_APPEND(zptr->z_rrlist, rrecp, r_glink);
}
/* 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) {
rcode = ISC_R_UNEXPECTED;
goto done;
}
ISC_LIST_PREPEND(zptr->z_rrlist, rrecp, r_glink);
zptr->z_flags |= ZG_F_ZONESECTADDED;
/* Marshall the update message. */
n = sizeof packet;
rcode = res_nmkupdate(statp,
ISC_LIST_HEAD(zptr->z_rrlist), packet, &n);
if (rcode != ISC_R_SUCCESS)
goto done;
/* Temporarily replace the resolver's nameserver set. */
nscount = nscopy(nsaddrs, statp->nsaddr_list, statp->nscount);
statp->nscount = nsprom(statp->nsaddr_list,
zptr->z_nsaddrs, zptr->z_nscount);
/* Send the update and remember the result. */
key = (ns_tsig_key *)0;
rcode = find_tsig_key (&key, zptr->z_origin, zcookie);
if (rcode == ISC_R_SUCCESS) {
rcode = res_nsendsigned(statp, packet, n, key,
answer, sizeof answer, &rval);
tkey_free (&key);
} else if (rcode == ISC_R_NOTFOUND || rcode == ISC_R_KEY_UNKNOWN) {
rcode = res_nsend(statp, packet, n,
answer, sizeof answer, &rval);
}
if (rcode != ISC_R_SUCCESS)
goto undone;
rcode = ns_rcode_to_isc (((HEADER *)answer)->rcode);
if (zcookie && rcode == ISC_R_BADSIG) {
repudiate_zone (&zcookie);
}
undone:
/* Restore resolver's nameserver set. */
statp->nscount = nscopy(statp->nsaddr_list, nsaddrs, nscount);
nscount = 0;
done:
if (zptr) {
if ((zptr->z_flags & ZG_F_ZONESECTADDED) != 0)
res_freeupdrec(ISC_LIST_HEAD(zptr->z_rrlist));
free(zptr);
}
/* If the update failed because we used a cached zone and it
didn't work, try it again without the cached zone. */
if (zcookp && (rcode == ISC_R_NOTZONE || rcode == ISC_R_BADSIG)) {
zcookp = 0;
goto again;
}
if (zcookie)
forget_zone (&zcookie);
return rcode;
}
/* Private. */
static int
nscopy(struct sockaddr_in *dst, const struct sockaddr_in *src, int n) {
int i;
for (i = 0; i < n; i++)
dst[i] = src[i];
return (n);
}
static int
nsprom(struct sockaddr_in *dst, const struct in_addr *src, int n) {
int i;
for (i = 0; i < n; i++) {
memset(&dst[i], 0, sizeof dst[i]);
dst[i].sin_family = AF_INET;
dst[i].sin_port = htons(NS_DEFAULTPORT);
dst[i].sin_addr = src[i];
}
return (n);
}
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