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 $"; 3 #endif /* not lint */ 4 5 /*- 6 * SPDX-License-Identifier: ISC 7 * 8 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 9 * Copyright (c) 1996-1999 by Internet Software Consortium. 10 * 11 * Permission to use, copy, modify, and distribute this software for any 12 * purpose with or without fee is hereby granted, provided that the above 13 * copyright notice and this permission notice appear in all copies. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 16 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 17 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 18 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 19 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 20 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 21 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 22 */ 23 24 /*! \file 25 * \brief 26 * Based on the Dynamic DNS reference implementation by Viraj Bais 27 * <viraj_bais@ccm.fm.intel.com> 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include "port_before.h" 34 35 #include <sys/param.h> 36 #include <sys/socket.h> 37 #include <sys/time.h> 38 39 #include <netinet/in.h> 40 #include <arpa/inet.h> 41 #include <arpa/nameser.h> 42 43 #include <errno.h> 44 #include <limits.h> 45 #include <netdb.h> 46 #include <res_update.h> 47 #include <stdarg.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <string.h> 51 52 #include <isc/list.h> 53 #include <resolv.h> 54 55 #include "port_after.h" 56 #include "res_private.h" 57 58 /*% 59 * Separate a linked list of records into groups so that all records 60 * in a group will belong to a single zone on the nameserver. 61 * Create a dynamic update packet for each zone and send it to the 62 * nameservers for that zone, and await answer. 63 * Abort if error occurs in updating any zone. 64 * Return the number of zones updated on success, < 0 on error. 65 * 66 * On error, caller must deal with the unsynchronized zones 67 * eg. an A record might have been successfully added to the forward 68 * zone but the corresponding PTR record would be missing if error 69 * was encountered while updating the reverse zone. 70 */ 71 72 struct zonegrp { 73 char z_origin[MAXDNAME]; 74 ns_class z_class; 75 union res_sockaddr_union z_nsaddrs[MAXNS]; 76 int z_nscount; 77 int z_flags; 78 LIST(ns_updrec) z_rrlist; 79 LINK(struct zonegrp) z_link; 80 }; 81 82 #define ZG_F_ZONESECTADDED 0x0001 83 84 /* Forward. */ 85 86 static void res_dprintf(const char *, ...) ISC_FORMAT_PRINTF(1, 2); 87 88 /* Macros. */ 89 90 #define DPRINTF(x) do {\ 91 int save_errno = errno; \ 92 if ((statp->options & RES_DEBUG) != 0U) res_dprintf x; \ 93 errno = save_errno; \ 94 } while (0) 95 96 /* Public. */ 97 98 int 99 res_nupdate(res_state statp, ns_updrec *rrecp_in, ns_tsig_key *key) { 100 ns_updrec *rrecp; 101 u_char answer[PACKETSZ]; 102 u_char *packet; 103 struct zonegrp *zptr, tgrp; 104 LIST(struct zonegrp) zgrps; 105 int nzones = 0, nscount = 0, n; 106 union res_sockaddr_union nsaddrs[MAXNS]; 107 108 packet = malloc(NS_MAXMSG); 109 if (packet == NULL) { 110 DPRINTF(("malloc failed")); 111 return (0); 112 } 113 /* Thread all of the updates onto a list of groups. */ 114 INIT_LIST(zgrps); 115 memset(&tgrp, 0, sizeof (tgrp)); 116 for (rrecp = rrecp_in; rrecp; 117 rrecp = LINKED(rrecp, r_link) ? NEXT(rrecp, r_link) : NULL) { 118 int nscnt; 119 /* Find the origin for it if there is one. */ 120 tgrp.z_class = rrecp->r_class; 121 nscnt = res_findzonecut2(statp, rrecp->r_dname, tgrp.z_class, 122 RES_EXHAUSTIVE, tgrp.z_origin, 123 sizeof tgrp.z_origin, 124 tgrp.z_nsaddrs, MAXNS); 125 if (nscnt <= 0) { 126 DPRINTF(("res_findzonecut failed (%d)", nscnt)); 127 goto done; 128 } 129 tgrp.z_nscount = nscnt; 130 /* Find the group for it if there is one. */ 131 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) 132 if (ns_samename(tgrp.z_origin, zptr->z_origin) == 1 && 133 tgrp.z_class == zptr->z_class) 134 break; 135 /* Make a group for it if there isn't one. */ 136 if (zptr == NULL) { 137 zptr = malloc(sizeof *zptr); 138 if (zptr == NULL) { 139 DPRINTF(("malloc failed")); 140 goto done; 141 } 142 *zptr = tgrp; 143 zptr->z_flags = 0; 144 INIT_LINK(zptr, z_link); 145 INIT_LIST(zptr->z_rrlist); 146 APPEND(zgrps, zptr, z_link); 147 } 148 /* Thread this rrecp onto the right group. */ 149 APPEND(zptr->z_rrlist, rrecp, r_glink); 150 } 151 152 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) { 153 /* Construct zone section and prepend it. */ 154 rrecp = res_mkupdrec(ns_s_zn, zptr->z_origin, 155 zptr->z_class, ns_t_soa, 0); 156 if (rrecp == NULL) { 157 DPRINTF(("res_mkupdrec failed")); 158 goto done; 159 } 160 PREPEND(zptr->z_rrlist, rrecp, r_glink); 161 zptr->z_flags |= ZG_F_ZONESECTADDED; 162 163 /* Marshall the update message. */ 164 n = res_nmkupdate(statp, HEAD(zptr->z_rrlist), 165 packet, NS_MAXMSG); 166 DPRINTF(("res_mkupdate -> %d", n)); 167 if (n < 0) 168 goto done; 169 170 /* Temporarily replace the resolver's nameserver set. */ 171 nscount = res_getservers(statp, nsaddrs, MAXNS); 172 res_setservers(statp, zptr->z_nsaddrs, zptr->z_nscount); 173 174 /* Send the update and remember the result. */ 175 if (key != NULL) { 176 #ifdef _LIBC 177 DPRINTF(("TSIG is not supported\n")); 178 RES_SET_H_ERRNO(statp, NO_RECOVERY); 179 goto done; 180 #else 181 n = res_nsendsigned(statp, packet, n, key, 182 answer, sizeof answer); 183 #endif 184 } else 185 n = res_nsend(statp, packet, n, answer, sizeof answer); 186 if (n < 0) { 187 DPRINTF(("res_nsend: send error, n=%d (%s)\n", 188 n, strerror(errno))); 189 goto done; 190 } 191 if (((HEADER *)answer)->rcode == NOERROR) 192 nzones++; 193 194 /* Restore resolver's nameserver set. */ 195 res_setservers(statp, nsaddrs, nscount); 196 nscount = 0; 197 } 198 done: 199 while (!EMPTY(zgrps)) { 200 zptr = HEAD(zgrps); 201 if ((zptr->z_flags & ZG_F_ZONESECTADDED) != 0) 202 res_freeupdrec(HEAD(zptr->z_rrlist)); 203 UNLINK(zgrps, zptr, z_link); 204 free(zptr); 205 } 206 if (nscount != 0) 207 res_setservers(statp, nsaddrs, nscount); 208 209 free(packet); 210 return (nzones); 211 } 212 213 /* Private. */ 214 215 static void 216 res_dprintf(const char *fmt, ...) { 217 va_list ap; 218 219 va_start(ap, fmt); 220 fputs(";; res_nupdate: ", stderr); 221 vfprintf(stderr, fmt, ap); 222 fputc('\n', stderr); 223 va_end(ap); 224 } 225