contrib/bind-9.2.4rc7/lib/bind/resolv/res_update.c

   1 #if !defined(lint) && !defined(SABER)
   2 static const char rcsid[] = "$Id: res_update.c,v 1.6.2.6 2004/03/16 12:35:37 marka Exp $";
   3 #endif /* not lint */
   4
   5 /*
   6  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   7  * Copyright (c) 1996-1999 by Internet Software Consortium.
   8  *
   9  * Permission to use, copy, modify, and distribute this software for any
  10  * purpose with or without fee is hereby granted, provided that the above
  11  * copyright notice and this permission notice appear in all copies.
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  14  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  15  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  16  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  17  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  18  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  19  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  20  */
  21
  22 /*
  23  * Based on the Dynamic DNS reference implementation by Viraj Bais
  24  * <viraj_bais@ccm.fm.intel.com>
  25  */
  26
  27 #include "port_before.h"
  28
  29 #include <sys/param.h>
  30 #include <sys/socket.h>
  31 #include <sys/time.h>
  32
  33 #include <netinet/in.h>
  34 #include <arpa/inet.h>
  35 #include <arpa/nameser.h>
  36
  37 #include <errno.h>
  38 #include <limits.h>
  39 #include <netdb.h>
  40 #include <res_update.h>
  41 #include <stdarg.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45
  46 #include <isc/list.h>
  47 #include <resolv.h>
  48
  49 #include "port_after.h"
  50 #include "res_private.h"
  51
  52 /*
  53  * Separate a linked list of records into groups so that all records
  54  * in a group will belong to a single zone on the nameserver.
  55  * Create a dynamic update packet for each zone and send it to the
  56  * nameservers for that zone, and await answer.
  57  * Abort if error occurs in updating any zone.
  58  * Return the number of zones updated on success, < 0 on error.
  59  *
  60  * On error, caller must deal with the unsynchronized zones
  61  * eg. an A record might have been successfully added to the forward
  62  * zone but the corresponding PTR record would be missing if error
  63  * was encountered while updating the reverse zone.
  64  */
  65
  66 struct zonegrp {
  67         char                    z_origin[MAXDNAME];
  68         ns_class                z_class;
  69         union res_sockaddr_union z_nsaddrs[MAXNS];
  70         int                     z_nscount;
  71         int                     z_flags;
  72         LIST(ns_updrec)         z_rrlist;
  73         LINK(struct zonegrp)    z_link;
  74 };
  75
  76 #define ZG_F_ZONESECTADDED      0x0001
  77
  78 /* Forward. */
  79
  80 static void     res_dprintf(const char *, ...) ISC_FORMAT_PRINTF(1, 2);
  81
  82 /* Macros. */
  83
  84 #define DPRINTF(x) do {\
  85                 int save_errno = errno; \
  86                 if ((statp->options & RES_DEBUG) != 0U) res_dprintf x; \
  87                 errno = save_errno; \
  88         } while (0)
  89
  90 /* Public. */
  91
  92 int
  93 res_nupdate(res_state statp, ns_updrec *rrecp_in, ns_tsig_key *key) {
  94         ns_updrec *rrecp;
  95         u_char answer[PACKETSZ];
  96         u_char *packet;
  97         struct zonegrp *zptr, tgrp;
  98         LIST(struct zonegrp) zgrps;
  99         int nzones = 0, nscount = 0, n;
 100         union res_sockaddr_union nsaddrs[MAXNS];
 101
 102         packet = malloc(NS_MAXMSG);
 103         if (packet == NULL) {
 104                 DPRINTF(("malloc failed"));
 105                 return (0);
 106         }
 107         /* Thread all of the updates onto a list of groups. */
 108         INIT_LIST(zgrps);
 109         memset(&tgrp, 0, sizeof (tgrp));
 110         for (rrecp = rrecp_in; rrecp;
 111              rrecp = LINKED(rrecp, r_link) ? NEXT(rrecp, r_link) : NULL) {
 112                 int nscnt;
 113                 /* Find the origin for it if there is one. */
 114                 tgrp.z_class = rrecp->r_class;
 115                 nscnt = res_findzonecut2(statp, rrecp->r_dname, tgrp.z_class,
 116                                          RES_EXHAUSTIVE, tgrp.z_origin,
 117                                          sizeof tgrp.z_origin,
 118                                          tgrp.z_nsaddrs, MAXNS);
 119                 if (nscnt <= 0) {
 120                         DPRINTF(("res_findzonecut failed (%d)", nscnt));
 121                         goto done;
 122                 }
 123                 tgrp.z_nscount = nscnt;
 124                 /* Find the group for it if there is one. */
 125                 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link))
 126                         if (ns_samename(tgrp.z_origin, zptr->z_origin) == 1 &&
 127                             tgrp.z_class == zptr->z_class)
 128                                 break;
 129                 /* Make a group for it if there isn't one. */
 130                 if (zptr == NULL) {
 131                         zptr = malloc(sizeof *zptr);
 132                         if (zptr == NULL) {
 133                                 DPRINTF(("malloc failed"));
 134                                 goto done;
 135                         }
 136                         *zptr = tgrp;
 137                         zptr->z_flags = 0;
 138                         INIT_LINK(zptr, z_link);
 139                         INIT_LIST(zptr->z_rrlist);
 140                         APPEND(zgrps, zptr, z_link);
 141                 }
 142                 /* Thread this rrecp onto the right group. */
 143                 APPEND(zptr->z_rrlist, rrecp, r_glink);
 144         }
 145
 146         for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) {
 147                 /* Construct zone section and prepend it. */
 148                 rrecp = res_mkupdrec(ns_s_zn, zptr->z_origin,
 149                                      zptr->z_class, ns_t_soa, 0);
 150                 if (rrecp == NULL) {
 151                         DPRINTF(("res_mkupdrec failed"));
 152                         goto done;
 153                 }
 154                 PREPEND(zptr->z_rrlist, rrecp, r_glink);
 155                 zptr->z_flags |= ZG_F_ZONESECTADDED;
 156
 157                 /* Marshall the update message. */
 158                 n = res_nmkupdate(statp, HEAD(zptr->z_rrlist),
 159                                   packet, NS_MAXMSG);
 160                 DPRINTF(("res_mkupdate -> %d", n));
 161                 if (n < 0)
 162                         goto done;
 163
 164                 /* Temporarily replace the resolver's nameserver set. */
 165                 nscount = res_getservers(statp, nsaddrs, MAXNS);
 166                 res_setservers(statp, zptr->z_nsaddrs, zptr->z_nscount);
 167
 168                 /* Send the update and remember the result. */
 169                 if (key != NULL)
 170                         n = res_nsendsigned(statp, packet, n, key,
 171                                             answer, sizeof answer);
 172                 else
 173                         n = res_nsend(statp, packet, n, answer, sizeof answer);
 174                 if (n < 0) {
 175                         DPRINTF(("res_nsend: send error, n=%d (%s)\n",
 176                                  n, strerror(errno)));
 177                         goto done;
 178                 }
 179                 if (((HEADER *)answer)->rcode == NOERROR)
 180                         nzones++;
 181
 182                 /* Restore resolver's nameserver set. */
 183                 res_setservers(statp, nsaddrs, nscount);
 184                 nscount = 0;
 185         }
 186  done:
 187         while (!EMPTY(zgrps)) {
 188                 zptr = HEAD(zgrps);
 189                 if ((zptr->z_flags & ZG_F_ZONESECTADDED) != 0)
 190                         res_freeupdrec(HEAD(zptr->z_rrlist));
 191                 UNLINK(zgrps, zptr, z_link);
 192                 free(zptr);
 193         }
 194         if (nscount != 0)
 195                 res_setservers(statp, nsaddrs, nscount);
 196
 197         free(packet);
 198         return (nzones);
 199 }
 200
 201 /* Private. */
 202
 203 static void
 204 res_dprintf(const char *fmt, ...) {
 205         va_list ap;
 206
 207         va_start(ap, fmt);
 208         fputs(";; res_nupdate: ", stderr);
 209         vfprintf(stderr, fmt, ap);
 210         fputc('\n', stderr);
 211         va_end(ap);
 212 }