1 /* 2 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 3 * Copyright (c) 1996-1999 by Internet Software Consortium. 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 15 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 * 17 * $Id: res_update.c,v 1.13 2005/04/27 04:56:43 sra Exp $ 18 */ 19 20 /*! \file 21 * \brief 22 * Based on the Dynamic DNS reference implementation by Viraj Bais 23 * <viraj_bais@ccm.fm.intel.com> 24 */ 25 26 #include "port_before.h" 27 28 #include <sys/param.h> 29 #include <sys/socket.h> 30 #include <sys/time.h> 31 32 #include <netinet/in.h> 33 #include <arpa/inet.h> 34 #include <arpa/nameser.h> 35 36 #include <errno.h> 37 #include <limits.h> 38 #include <netdb.h> 39 #include <res_update.h> 40 #include <stdarg.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <string.h> 44 45 #include "isc/list.h" 46 #include <resolv.h> 47 48 #include "port_after.h" 49 #include "res_private.h" 50 51 /*% 52 * Separate a linked list of records into groups so that all records 53 * in a group will belong to a single zone on the nameserver. 54 * Create a dynamic update packet for each zone and send it to the 55 * nameservers for that zone, and await answer. 56 * Abort if error occurs in updating any zone. 57 * Return the number of zones updated on success, < 0 on error. 58 * 59 * On error, caller must deal with the unsynchronized zones 60 * eg. an A record might have been successfully added to the forward 61 * zone but the corresponding PTR record would be missing if error 62 * was encountered while updating the reverse zone. 63 */ 64 65 struct zonegrp { 66 char z_origin[MAXDNAME]; 67 ns_class z_class; 68 union res_sockaddr_union z_nsaddrs[MAXNS]; 69 int z_nscount; 70 int z_flags; 71 LIST(ns_updrec) z_rrlist; 72 LINK(struct zonegrp) z_link; 73 }; 74 75 #define ZG_F_ZONESECTADDED 0x0001 76 77 /* Forward. */ 78 79 static void res_dprintf(const char *, ...) ISC_FORMAT_PRINTF(1, 2); 80 81 /* Macros. */ 82 83 #define DPRINTF(x) do {\ 84 int save_errno = errno; \ 85 if ((statp->options & RES_DEBUG) != 0U) res_dprintf x; \ 86 errno = save_errno; \ 87 } while (0) 88 89 /* Public. */ 90 91 int 92 res_nupdate(res_state statp, ns_updrec *rrecp_in, ns_tsig_key *key) { 93 ns_updrec *rrecp; 94 u_char answer[PACKETSZ]; 95 u_char *packet; 96 struct zonegrp *zptr, tgrp; 97 LIST(struct zonegrp) zgrps; 98 int nzones = 0, nscount = 0, n; 99 union res_sockaddr_union nsaddrs[MAXNS]; 100 101 packet = malloc(NS_MAXMSG); 102 if (packet == NULL) { 103 DPRINTF(("malloc failed")); 104 return (0); 105 } 106 /* Thread all of the updates onto a list of groups. */ 107 INIT_LIST(zgrps); 108 memset(&tgrp, 0, sizeof (tgrp)); 109 for (rrecp = rrecp_in; rrecp; 110 rrecp = LINKED(rrecp, r_link) ? NEXT(rrecp, r_link) : NULL) { 111 int nscnt; 112 /* Find the origin for it if there is one. */ 113 tgrp.z_class = rrecp->r_class; 114 nscnt = res_findzonecut2(statp, rrecp->r_dname, tgrp.z_class, 115 RES_EXHAUSTIVE, tgrp.z_origin, 116 sizeof tgrp.z_origin, 117 tgrp.z_nsaddrs, MAXNS); 118 if (nscnt <= 0) { 119 DPRINTF(("res_findzonecut failed (%d)", nscnt)); 120 goto done; 121 } 122 tgrp.z_nscount = nscnt; 123 /* Find the group for it if there is one. */ 124 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) 125 if (ns_samename(tgrp.z_origin, zptr->z_origin) == 1 && 126 tgrp.z_class == zptr->z_class) 127 break; 128 /* Make a group for it if there isn't one. */ 129 if (zptr == NULL) { 130 zptr = malloc(sizeof *zptr); 131 if (zptr == NULL) { 132 DPRINTF(("malloc failed")); 133 goto done; 134 } 135 *zptr = tgrp; 136 zptr->z_flags = 0; 137 INIT_LINK(zptr, z_link); 138 INIT_LIST(zptr->z_rrlist); 139 APPEND(zgrps, zptr, z_link); 140 } 141 /* Thread this rrecp onto the right group. */ 142 APPEND(zptr->z_rrlist, rrecp, r_glink); 143 } 144 145 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) { 146 /* Construct zone section and prepend it. */ 147 rrecp = res_mkupdrec(ns_s_zn, zptr->z_origin, 148 zptr->z_class, ns_t_soa, 0); 149 if (rrecp == NULL) { 150 DPRINTF(("res_mkupdrec failed")); 151 goto done; 152 } 153 PREPEND(zptr->z_rrlist, rrecp, r_glink); 154 zptr->z_flags |= ZG_F_ZONESECTADDED; 155 156 /* Marshall the update message. */ 157 n = res_nmkupdate(statp, HEAD(zptr->z_rrlist), 158 packet, NS_MAXMSG); 159 DPRINTF(("res_mkupdate -> %d", n)); 160 if (n < 0) 161 goto done; 162 163 /* Temporarily replace the resolver's nameserver set. */ 164 nscount = res_getservers(statp, nsaddrs, MAXNS); 165 res_setservers(statp, zptr->z_nsaddrs, zptr->z_nscount); 166 167 /* Send the update and remember the result. */ 168 if (key != NULL) 169 #ifdef _LIBC 170 { 171 DPRINTF(("TSIG is not supported\n")); 172 RES_SET_H_ERRNO(statp, NO_RECOVERY); 173 goto done; 174 } 175 #else 176 n = res_nsendsigned(statp, packet, n, key, 177 answer, sizeof answer); 178 #endif 179 else 180 n = res_nsend(statp, packet, n, answer, sizeof answer); 181 if (n < 0) { 182 DPRINTF(("res_nsend: send error, n=%d (%s)\n", 183 n, strerror(errno))); 184 goto done; 185 } 186 if (((HEADER *)answer)->rcode == NOERROR) 187 nzones++; 188 189 /* Restore resolver's nameserver set. */ 190 res_setservers(statp, nsaddrs, nscount); 191 nscount = 0; 192 } 193 done: 194 while (!EMPTY(zgrps)) { 195 zptr = HEAD(zgrps); 196 if ((zptr->z_flags & ZG_F_ZONESECTADDED) != 0) 197 res_freeupdrec(HEAD(zptr->z_rrlist)); 198 UNLINK(zgrps, zptr, z_link); 199 free(zptr); 200 } 201 if (nscount != 0) 202 res_setservers(statp, nsaddrs, nscount); 203 204 free(packet); 205 return (nzones); 206 } 207 208 /* Private. */ 209 210 static void 211 res_dprintf(const char *fmt, ...) { 212 va_list ap; 213 214 va_start(ap, fmt); 215 fputs(";; res_nupdate: ", stderr); 216 vfprintf(stderr, fmt, ap); 217 fputc('\n', stderr); 218 va_end(ap); 219 } 220