1 #if !defined(lint) && !defined(SABER) 2 static const char rcsid[] = "$Id: res_update.c,v 1.13 2005/04/27 04:56:43 sra 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 /*! \file 23 * \brief 24 * Based on the Dynamic DNS reference implementation by Viraj Bais 25 * <viraj_bais@ccm.fm.intel.com> 26 */ 27 28 #include "port_before.h" 29 30 #include <sys/param.h> 31 #include <sys/socket.h> 32 #include <sys/time.h> 33 34 #include <netinet/in.h> 35 #include <arpa/inet.h> 36 #include <arpa/nameser.h> 37 38 #include <errno.h> 39 #include <limits.h> 40 #include <netdb.h> 41 #include <res_update.h> 42 #include <stdarg.h> 43 #include <stdio.h> 44 #include <stdlib.h> 45 #include <string.h> 46 47 #include <isc/list.h> 48 #include <resolv.h> 49 50 #include "port_after.h" 51 #include "res_private.h" 52 53 /*% 54 * Separate a linked list of records into groups so that all records 55 * in a group will belong to a single zone on the nameserver. 56 * Create a dynamic update packet for each zone and send it to the 57 * nameservers for that zone, and await answer. 58 * Abort if error occurs in updating any zone. 59 * Return the number of zones updated on success, < 0 on error. 60 * 61 * On error, caller must deal with the unsynchronized zones 62 * eg. an A record might have been successfully added to the forward 63 * zone but the corresponding PTR record would be missing if error 64 * was encountered while updating the reverse zone. 65 */ 66 67 struct zonegrp { 68 char z_origin[MAXDNAME]; 69 ns_class z_class; 70 union res_sockaddr_union z_nsaddrs[MAXNS]; 71 int z_nscount; 72 int z_flags; 73 LIST(ns_updrec) z_rrlist; 74 LINK(struct zonegrp) z_link; 75 }; 76 77 #define ZG_F_ZONESECTADDED 0x0001 78 79 /* Forward. */ 80 81 static void res_dprintf(const char *, ...) ISC_FORMAT_PRINTF(1, 2); 82 83 /* Macros. */ 84 85 #define DPRINTF(x) do {\ 86 int save_errno = errno; \ 87 if ((statp->options & RES_DEBUG) != 0U) res_dprintf x; \ 88 errno = save_errno; \ 89 } while (0) 90 91 /* Public. */ 92 93 int 94 res_nupdate(res_state statp, ns_updrec *rrecp_in, ns_tsig_key *key) { 95 ns_updrec *rrecp; 96 u_char answer[PACKETSZ]; 97 u_char *packet; 98 struct zonegrp *zptr, tgrp; 99 LIST(struct zonegrp) zgrps; 100 int nzones = 0, nscount = 0, n; 101 union res_sockaddr_union nsaddrs[MAXNS]; 102 103 packet = malloc(NS_MAXMSG); 104 if (packet == NULL) { 105 DPRINTF(("malloc failed")); 106 return (0); 107 } 108 /* Thread all of the updates onto a list of groups. */ 109 INIT_LIST(zgrps); 110 memset(&tgrp, 0, sizeof (tgrp)); 111 for (rrecp = rrecp_in; rrecp; 112 rrecp = LINKED(rrecp, r_link) ? NEXT(rrecp, r_link) : NULL) { 113 int nscnt; 114 /* Find the origin for it if there is one. */ 115 tgrp.z_class = rrecp->r_class; 116 nscnt = res_findzonecut2(statp, rrecp->r_dname, tgrp.z_class, 117 RES_EXHAUSTIVE, tgrp.z_origin, 118 sizeof tgrp.z_origin, 119 tgrp.z_nsaddrs, MAXNS); 120 if (nscnt <= 0) { 121 DPRINTF(("res_findzonecut failed (%d)", nscnt)); 122 goto done; 123 } 124 tgrp.z_nscount = nscnt; 125 /* Find the group for it if there is one. */ 126 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) 127 if (ns_samename(tgrp.z_origin, zptr->z_origin) == 1 && 128 tgrp.z_class == zptr->z_class) 129 break; 130 /* Make a group for it if there isn't one. */ 131 if (zptr == NULL) { 132 zptr = malloc(sizeof *zptr); 133 if (zptr == NULL) { 134 DPRINTF(("malloc failed")); 135 goto done; 136 } 137 *zptr = tgrp; 138 zptr->z_flags = 0; 139 INIT_LINK(zptr, z_link); 140 INIT_LIST(zptr->z_rrlist); 141 APPEND(zgrps, zptr, z_link); 142 } 143 /* Thread this rrecp onto the right group. */ 144 APPEND(zptr->z_rrlist, rrecp, r_glink); 145 } 146 147 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) { 148 /* Construct zone section and prepend it. */ 149 rrecp = res_mkupdrec(ns_s_zn, zptr->z_origin, 150 zptr->z_class, ns_t_soa, 0); 151 if (rrecp == NULL) { 152 DPRINTF(("res_mkupdrec failed")); 153 goto done; 154 } 155 PREPEND(zptr->z_rrlist, rrecp, r_glink); 156 zptr->z_flags |= ZG_F_ZONESECTADDED; 157 158 /* Marshall the update message. */ 159 n = res_nmkupdate(statp, HEAD(zptr->z_rrlist), 160 packet, NS_MAXMSG); 161 DPRINTF(("res_mkupdate -> %d", n)); 162 if (n < 0) 163 goto done; 164 165 /* Temporarily replace the resolver's nameserver set. */ 166 nscount = res_getservers(statp, nsaddrs, MAXNS); 167 res_setservers(statp, zptr->z_nsaddrs, zptr->z_nscount); 168 169 /* Send the update and remember the result. */ 170 if (key != NULL) 171 n = res_nsendsigned(statp, packet, n, key, 172 answer, sizeof answer); 173 else 174 n = res_nsend(statp, packet, n, answer, sizeof answer); 175 if (n < 0) { 176 DPRINTF(("res_nsend: send error, n=%d (%s)\n", 177 n, strerror(errno))); 178 goto done; 179 } 180 if (((HEADER *)answer)->rcode == NOERROR) 181 nzones++; 182 183 /* Restore resolver's nameserver set. */ 184 res_setservers(statp, nsaddrs, nscount); 185 nscount = 0; 186 } 187 done: 188 while (!EMPTY(zgrps)) { 189 zptr = HEAD(zgrps); 190 if ((zptr->z_flags & ZG_F_ZONESECTADDED) != 0) 191 res_freeupdrec(HEAD(zptr->z_rrlist)); 192 UNLINK(zgrps, zptr, z_link); 193 free(zptr); 194 } 195 if (nscount != 0) 196 res_setservers(statp, nsaddrs, nscount); 197 198 free(packet); 199 return (nzones); 200 } 201 202 /* Private. */ 203 204 static void 205 res_dprintf(const char *fmt, ...) { 206 va_list ap; 207 208 va_start(ap, fmt); 209 fputs(";; res_nupdate: ", stderr); 210 vfprintf(stderr, fmt, ap); 211 fputc('\n', stderr); 212 va_end(ap); 213 } 214