workbench/network/stacks/AROSTCP/dhcp/minires/res_update.c

   1 #if !defined(lint) && !defined(SABER) && !defined(__AROS__)
   2 static const char rcsid[] = "$Id$";
   3 #endif /* not lint */
   4
   5 /*
   6  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   7  * Copyright (c) 1996-2003 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  *   Internet Systems Consortium, Inc.
  22  *   950 Charter Street
  23  *   Redwood City, CA 94063
  24  *   <info@isc.org>
  25  *   http://www.isc.org/
  26  */
  27
  28 /*
  29  * Based on the Dynamic DNS reference implementation by Viraj Bais
  30  * <viraj_bais@ccm.fm.intel.com>
  31  */
  32
  33 #include <sys/param.h>
  34 #include <sys/socket.h>
  35 #include <sys/time.h>
  36
  37 #include <netinet/in.h>
  38 #include <arpa/inet.h>
  39
  40 #include <errno.h>
  41 #include <limits.h>
  42 #include <netdb.h>
  43 #include <stdarg.h>
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <string.h>
  47
  48 #include <isc-dhcp/list.h>
  49 #include "minires/minires.h"
  50 #include "arpa/nameser.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         struct in_addr z_nsaddrs[MAXNS];
  70         int z_nscount;
  71         int z_flags;
  72         ISC_LIST(ns_updrec) z_rrlist;
  73         ISC_LINK(struct zonegrp) z_link;
  74 };
  75
  76 #define ZG_F_ZONESECTADDED      0x0001
  77
  78 /* Forward. */
  79
  80 static int      nscopy(struct sockaddr_in *, const struct sockaddr_in *, int);
  81 static int      nsprom(struct sockaddr_in *, const struct in_addr *, int);
  82
  83 void tkey_free (ns_tsig_key **);
  84
  85 isc_result_t
  86 res_nupdate(res_state statp, ns_updrec *rrecp_in) {
  87         ns_updrec *rrecp;
  88         union {
  89             double answer[PACKETSZ / sizeof (double)];
  90             HEADER h;
  91         } __tmp;
  92         double packet[2*PACKETSZ / sizeof (double)];
  93         struct zonegrp *zptr, tgrp;
  94         int nscount = 0;
  95         // int nzones = 0;
  96         unsigned n;
  97         unsigned rval;
  98         struct sockaddr_in nsaddrs[MAXNS];
  99         ns_tsig_key *key;
 100         void *zcookie = 0;
 101         void *zcookp = &zcookie;
 102         isc_result_t rcode;
 103
 104       again:
 105         /* Make sure all the updates are in the same zone, and find out
 106            what zone they are in. */
 107         zptr = NULL;
 108         for (rrecp = rrecp_in; rrecp; rrecp = ISC_LIST_NEXT(rrecp, r_link)) {
 109                 /* Find the origin for it if there is one. */
 110                 tgrp.z_class = rrecp->r_class;
 111                 rcode = res_findzonecut(statp, rrecp->r_dname, tgrp.z_class,
 112                                         RES_EXHAUSTIVE,
 113                                         tgrp.z_origin,
 114                                         sizeof tgrp.z_origin,
 115                                         tgrp.z_nsaddrs, MAXNS, &tgrp.z_nscount,
 116                                         zcookp);
 117                 if (rcode != ISC_R_SUCCESS)
 118                         goto done;
 119                 if (tgrp.z_nscount <= 0) {
 120                         rcode = ISC_R_NOTZONE;
 121                         goto done;
 122                 }
 123                 /* Make a group for it if there isn't one. */
 124                 if (zptr == NULL) {
 125                         zptr = malloc(sizeof *zptr);
 126                         if (zptr == NULL) {
 127                                 rcode = ISC_R_NOMEMORY;
 128                                 goto done;
 129                         }
 130                         *zptr = tgrp;
 131                         zptr->z_flags = 0;
 132                         ISC_LIST_INIT(zptr->z_rrlist);
 133                 } else if (ns_samename(tgrp.z_origin, zptr->z_origin) == 0 ||
 134                            tgrp.z_class != zptr->z_class) {
 135                         /* Some of the records are in different zones. */
 136                         rcode = ISC_R_CROSSZONE;
 137                         goto done;
 138                 }
 139                 /* Thread this rrecp onto the zone group. */
 140                 ISC_LIST_APPEND(zptr->z_rrlist, rrecp, r_glink);
 141         }
 142
 143         /* Construct zone section and prepend it. */
 144         rrecp = res_mkupdrec(ns_s_zn, zptr->z_origin,
 145                              zptr->z_class, ns_t_soa, 0);
 146         if (rrecp == NULL) {
 147                 rcode = ISC_R_UNEXPECTED;
 148                 goto done;
 149         }
 150         ISC_LIST_PREPEND(zptr->z_rrlist, rrecp, r_glink);
 151         zptr->z_flags |= ZG_F_ZONESECTADDED;
 152
 153         /* Marshall the update message. */
 154         n = sizeof packet;
 155         rcode = res_nmkupdate(statp,
 156                               ISC_LIST_HEAD(zptr->z_rrlist), packet, &n);
 157         if (rcode != ISC_R_SUCCESS)
 158                 goto done;
 159
 160         /* Temporarily replace the resolver's nameserver set. */
 161         nscount = nscopy(nsaddrs, statp->nsaddr_list, statp->nscount);
 162         statp->nscount = nsprom(statp->nsaddr_list,
 163                                 zptr->z_nsaddrs, zptr->z_nscount);
 164
 165         /* Send the update and remember the result. */
 166         key = (ns_tsig_key *)0;
 167         rcode = find_tsig_key (&key, zptr->z_origin, zcookie);
 168         if (rcode == ISC_R_SUCCESS) {
 169                 rcode = res_nsendsigned(statp, packet, n, key,
 170                                         __tmp.answer, sizeof __tmp.answer, &rval);
 171                 tkey_free (&key);
 172         } else if (rcode == ISC_R_NOTFOUND || rcode == ISC_R_KEY_UNKNOWN) {
 173                 rcode = res_nsend(statp, packet, n,
 174                                   __tmp.answer, sizeof __tmp.answer, &rval);
 175         }
 176         if (rcode != ISC_R_SUCCESS)
 177                 goto undone;
 178
 179         rcode = ns_rcode_to_isc (__tmp.h.rcode);
 180         if (zcookie && rcode == ISC_R_BADSIG) {
 181                 repudiate_zone (&zcookie);
 182         }
 183
 184  undone:
 185         /* Restore resolver's nameserver set. */
 186         statp->nscount = nscopy(statp->nsaddr_list, nsaddrs, nscount);
 187         nscount = 0;
 188  done:
 189         if (zptr) {
 190                 if ((zptr->z_flags & ZG_F_ZONESECTADDED) != 0)
 191                         res_freeupdrec(ISC_LIST_HEAD(zptr->z_rrlist));
 192                 free(zptr);
 193         }
 194
 195         /* If the update failed because we used a cached zone and it
 196            didn't work, try it again without the cached zone. */
 197         if (zcookp && (rcode == ISC_R_NOTZONE || rcode == ISC_R_BADSIG)) {
 198                 zcookp = 0;
 199                 goto again;
 200         }
 201
 202         if (zcookie)
 203                 forget_zone (&zcookie);
 204         return rcode;
 205 }
 206
 207 /* Private. */
 208
 209 static int
 210 nscopy(struct sockaddr_in *dst, const struct sockaddr_in *src, int n) {
 211         int i;
 212
 213         for (i = 0; i < n; i++)
 214                 dst[i] = src[i];
 215         return (n);
 216 }
 217
 218 static int
 219 nsprom(struct sockaddr_in *dst, const struct in_addr *src, int n) {
 220         int i;
 221
 222         for (i = 0; i < n; i++) {
 223                 memset(&dst[i], 0, sizeof dst[i]);
 224                 dst[i].sin_family = AF_INET;
 225                 dst[i].sin_port = htons(NS_DEFAULTPORT);
 226                 dst[i].sin_addr = src[i];
 227         }
 228         return (n);
 229 }