1 /* $NetBSD: res_update.c,v 1.1.1.1 2009/04/12 15:33:55 christos Exp $ */ 2 3 #if !defined(lint) && !defined(SABER) 4 static const char rcsid[] = "Id: res_update.c,v 1.13 2005/04/27 04:56:43 sra Exp"; 5 #endif /* not lint */ 6 7 /* 8 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 9 * Copyright (c) 1996-1999 by Internet Software Consortium. 10 * 11 * Permission to use, copy, modify, and distribute this software for any 12 * purpose with or without fee is hereby granted, provided that the above 13 * copyright notice and this permission notice appear in all copies. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 16 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 17 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 18 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 19 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 20 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 21 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 22 */ 23 24 /*! \file 25 * \brief 26 * Based on the Dynamic DNS reference implementation by Viraj Bais 27 * <viraj_bais@ccm.fm.intel.com> 28 */ 29 30 #include "port_before.h" 31 32 #include <sys/param.h> 33 #include <sys/socket.h> 34 #include <sys/time.h> 35 36 #include <netinet/in.h> 37 #include <arpa/inet.h> 38 #include <arpa/nameser.h> 39 40 #include <errno.h> 41 #include <limits.h> 42 #include <netdb.h> 43 #include <res_update.h> 44 #include <stdarg.h> 45 #include <stdio.h> 46 #include <stdlib.h> 47 #include <string.h> 48 49 #include <isc/list.h> 50 #include <resolv.h> 51 52 #include "port_after.h" 53 #include "res_private.h" 54 55 /*% 56 * Separate a linked list of records into groups so that all records 57 * in a group will belong to a single zone on the nameserver. 58 * Create a dynamic update packet for each zone and send it to the 59 * nameservers for that zone, and await answer. 60 * Abort if error occurs in updating any zone. 61 * Return the number of zones updated on success, < 0 on error. 62 * 63 * On error, caller must deal with the unsynchronized zones 64 * eg. an A record might have been successfully added to the forward 65 * zone but the corresponding PTR record would be missing if error 66 * was encountered while updating the reverse zone. 67 */ 68 69 struct zonegrp { 70 char z_origin[MAXDNAME]; 71 ns_class z_class; 72 union res_sockaddr_union z_nsaddrs[MAXNS]; 73 int z_nscount; 74 int z_flags; 75 LIST(ns_updrec) z_rrlist; 76 LINK(struct zonegrp) z_link; 77 }; 78 79 #define ZG_F_ZONESECTADDED 0x0001 80 81 /* Forward. */ 82 83 static void res_dprintf(const char *, ...) ISC_FORMAT_PRINTF(1, 2); 84 85 /* Macros. */ 86 87 #define DPRINTF(x) do {\ 88 int save_errno = errno; \ 89 if ((statp->options & RES_DEBUG) != 0U) res_dprintf x; \ 90 errno = save_errno; \ 91 } while (0) 92 93 /* Public. */ 94 95 int 96 res_nupdate(res_state statp, ns_updrec *rrecp_in, ns_tsig_key *key) { 97 ns_updrec *rrecp; 98 u_char answer[PACKETSZ]; 99 u_char *packet; 100 struct zonegrp *zptr, tgrp; 101 LIST(struct zonegrp) zgrps; 102 int nzones = 0, nscount = 0, n; 103 union res_sockaddr_union nsaddrs[MAXNS]; 104 105 packet = malloc(NS_MAXMSG); 106 if (packet == NULL) { 107 DPRINTF(("malloc failed")); 108 return (0); 109 } 110 /* Thread all of the updates onto a list of groups. */ 111 INIT_LIST(zgrps); 112 memset(&tgrp, 0, sizeof (tgrp)); 113 for (rrecp = rrecp_in; rrecp; 114 rrecp = LINKED(rrecp, r_link) ? NEXT(rrecp, r_link) : NULL) { 115 int nscnt; 116 /* Find the origin for it if there is one. */ 117 tgrp.z_class = rrecp->r_class; 118 nscnt = res_findzonecut2(statp, rrecp->r_dname, tgrp.z_class, 119 RES_EXHAUSTIVE, tgrp.z_origin, 120 sizeof tgrp.z_origin, 121 tgrp.z_nsaddrs, MAXNS); 122 if (nscnt <= 0) { 123 DPRINTF(("res_findzonecut failed (%d)", nscnt)); 124 goto done; 125 } 126 tgrp.z_nscount = nscnt; 127 /* Find the group for it if there is one. */ 128 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) 129 if (ns_samename(tgrp.z_origin, zptr->z_origin) == 1 && 130 tgrp.z_class == zptr->z_class) 131 break; 132 /* Make a group for it if there isn't one. */ 133 if (zptr == NULL) { 134 zptr = malloc(sizeof *zptr); 135 if (zptr == NULL) { 136 DPRINTF(("malloc failed")); 137 goto done; 138 } 139 *zptr = tgrp; 140 zptr->z_flags = 0; 141 INIT_LINK(zptr, z_link); 142 INIT_LIST(zptr->z_rrlist); 143 APPEND(zgrps, zptr, z_link); 144 } 145 /* Thread this rrecp onto the right group. */ 146 APPEND(zptr->z_rrlist, rrecp, r_glink); 147 } 148 149 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) { 150 /* Construct zone section and prepend it. */ 151 rrecp = res_mkupdrec(ns_s_zn, zptr->z_origin, 152 zptr->z_class, ns_t_soa, 0); 153 if (rrecp == NULL) { 154 DPRINTF(("res_mkupdrec failed")); 155 goto done; 156 } 157 PREPEND(zptr->z_rrlist, rrecp, r_glink); 158 zptr->z_flags |= ZG_F_ZONESECTADDED; 159 160 /* Marshall the update message. */ 161 n = res_nmkupdate(statp, HEAD(zptr->z_rrlist), 162 packet, NS_MAXMSG); 163 DPRINTF(("res_mkupdate -> %d", n)); 164 if (n < 0) 165 goto done; 166 167 /* Temporarily replace the resolver's nameserver set. */ 168 nscount = res_getservers(statp, nsaddrs, MAXNS); 169 res_setservers(statp, zptr->z_nsaddrs, zptr->z_nscount); 170 171 /* Send the update and remember the result. */ 172 if (key != NULL) 173 n = res_nsendsigned(statp, packet, n, key, 174 answer, sizeof answer); 175 else 176 n = res_nsend(statp, packet, n, answer, sizeof answer); 177 if (n < 0) { 178 DPRINTF(("res_nsend: send error, n=%d (%s)\n", 179 n, strerror(errno))); 180 goto done; 181 } 182 if (((HEADER *)answer)->rcode == NOERROR) 183 nzones++; 184 185 /* Restore resolver's nameserver set. */ 186 res_setservers(statp, nsaddrs, nscount); 187 nscount = 0; 188 } 189 done: 190 while (!EMPTY(zgrps)) { 191 zptr = HEAD(zgrps); 192 if ((zptr->z_flags & ZG_F_ZONESECTADDED) != 0) 193 res_freeupdrec(HEAD(zptr->z_rrlist)); 194 UNLINK(zgrps, zptr, z_link); 195 free(zptr); 196 } 197 if (nscount != 0) 198 res_setservers(statp, nsaddrs, nscount); 199 200 free(packet); 201 return (nzones); 202 } 203 204 /* Private. */ 205 206 static void 207 res_dprintf(const char *fmt, ...) { 208 va_list ap; 209 210 va_start(ap, fmt); 211 fputs(";; res_nupdate: ", stderr); 212 vfprintf(stderr, fmt, ap); 213 fputc('\n', stderr); 214 va_end(ap); 215 } 216