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 #include "port_before.h" 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 #include <arpa/nameser.h> 40 41 #include <errno.h> 42 #include <limits.h> 43 #include <netdb.h> 44 #include <res_update.h> 45 #include <stdarg.h> 46 #include <stdio.h> 47 #include <stdlib.h> 48 #include <string.h> 49 50 #include <isc/list.h> 51 #include <resolv.h> 52 53 #include "port_after.h" 54 #include "res_private.h" 55 56 /*% 57 * Separate a linked list of records into groups so that all records 58 * in a group will belong to a single zone on the nameserver. 59 * Create a dynamic update packet for each zone and send it to the 60 * nameservers for that zone, and await answer. 61 * Abort if error occurs in updating any zone. 62 * Return the number of zones updated on success, < 0 on error. 63 * 64 * On error, caller must deal with the unsynchronized zones 65 * eg. an A record might have been successfully added to the forward 66 * zone but the corresponding PTR record would be missing if error 67 * was encountered while updating the reverse zone. 68 */ 69 70 struct zonegrp { 71 char z_origin[MAXDNAME]; 72 ns_class z_class; 73 union res_sockaddr_union z_nsaddrs[MAXNS]; 74 int z_nscount; 75 int z_flags; 76 LIST(ns_updrec) z_rrlist; 77 LINK(struct zonegrp) z_link; 78 }; 79 80 #define ZG_F_ZONESECTADDED 0x0001 81 82 /* Forward. */ 83 84 static void res_dprintf(const char *, ...) ISC_FORMAT_PRINTF(1, 2); 85 86 /* Macros. */ 87 88 #define DPRINTF(x) do {\ 89 int save_errno = errno; \ 90 if ((statp->options & RES_DEBUG) != 0U) res_dprintf x; \ 91 errno = save_errno; \ 92 } while (0) 93 94 /* Public. */ 95 96 int 97 res_nupdate(res_state statp, ns_updrec *rrecp_in, ns_tsig_key *key) { 98 ns_updrec *rrecp; 99 u_char answer[PACKETSZ]; 100 u_char *packet; 101 struct zonegrp *zptr, tgrp; 102 LIST(struct zonegrp) zgrps; 103 int nzones = 0, nscount = 0, n; 104 union res_sockaddr_union nsaddrs[MAXNS]; 105 106 packet = malloc(NS_MAXMSG); 107 if (packet == NULL) { 108 DPRINTF(("malloc failed")); 109 return (0); 110 } 111 /* Thread all of the updates onto a list of groups. */ 112 INIT_LIST(zgrps); 113 memset(&tgrp, 0, sizeof (tgrp)); 114 for (rrecp = rrecp_in; rrecp; 115 rrecp = LINKED(rrecp, r_link) ? NEXT(rrecp, r_link) : NULL) { 116 int nscnt; 117 /* Find the origin for it if there is one. */ 118 tgrp.z_class = rrecp->r_class; 119 nscnt = res_findzonecut2(statp, rrecp->r_dname, tgrp.z_class, 120 RES_EXHAUSTIVE, tgrp.z_origin, 121 sizeof tgrp.z_origin, 122 tgrp.z_nsaddrs, MAXNS); 123 if (nscnt <= 0) { 124 DPRINTF(("res_findzonecut failed (%d)", nscnt)); 125 goto done; 126 } 127 tgrp.z_nscount = nscnt; 128 /* Find the group for it if there is one. */ 129 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) 130 if (ns_samename(tgrp.z_origin, zptr->z_origin) == 1 && 131 tgrp.z_class == zptr->z_class) 132 break; 133 /* Make a group for it if there isn't one. */ 134 if (zptr == NULL) { 135 zptr = malloc(sizeof *zptr); 136 if (zptr == NULL) { 137 DPRINTF(("malloc failed")); 138 goto done; 139 } 140 *zptr = tgrp; 141 zptr->z_flags = 0; 142 INIT_LINK(zptr, z_link); 143 INIT_LIST(zptr->z_rrlist); 144 APPEND(zgrps, zptr, z_link); 145 } 146 /* Thread this rrecp onto the right group. */ 147 APPEND(zptr->z_rrlist, rrecp, r_glink); 148 } 149 150 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) { 151 /* Construct zone section and prepend it. */ 152 rrecp = res_mkupdrec(ns_s_zn, zptr->z_origin, 153 zptr->z_class, ns_t_soa, 0); 154 if (rrecp == NULL) { 155 DPRINTF(("res_mkupdrec failed")); 156 goto done; 157 } 158 PREPEND(zptr->z_rrlist, rrecp, r_glink); 159 zptr->z_flags |= ZG_F_ZONESECTADDED; 160 161 /* Marshall the update message. */ 162 n = res_nmkupdate(statp, HEAD(zptr->z_rrlist), 163 packet, NS_MAXMSG); 164 DPRINTF(("res_mkupdate -> %d", n)); 165 if (n < 0) 166 goto done; 167 168 /* Temporarily replace the resolver's nameserver set. */ 169 nscount = res_getservers(statp, nsaddrs, MAXNS); 170 res_setservers(statp, zptr->z_nsaddrs, zptr->z_nscount); 171 172 /* Send the update and remember the result. */ 173 if (key != NULL) { 174 #ifdef _LIBC 175 DPRINTF(("TSIG is not supported\n")); 176 RES_SET_H_ERRNO(statp, NO_RECOVERY); 177 goto done; 178 #else 179 n = res_nsendsigned(statp, packet, n, key, 180 answer, sizeof answer); 181 #endif 182 } else 183 n = res_nsend(statp, packet, n, answer, sizeof answer); 184 if (n < 0) { 185 DPRINTF(("res_nsend: send error, n=%d (%s)\n", 186 n, strerror(errno))); 187 goto done; 188 } 189 if (((HEADER *)answer)->rcode == NOERROR) 190 nzones++; 191 192 /* Restore resolver's nameserver set. */ 193 res_setservers(statp, nsaddrs, nscount); 194 nscount = 0; 195 } 196 done: 197 while (!EMPTY(zgrps)) { 198 zptr = HEAD(zgrps); 199 if ((zptr->z_flags & ZG_F_ZONESECTADDED) != 0) 200 res_freeupdrec(HEAD(zptr->z_rrlist)); 201 UNLINK(zgrps, zptr, z_link); 202 free(zptr); 203 } 204 if (nscount != 0) 205 res_setservers(statp, nsaddrs, nscount); 206 207 free(packet); 208 return (nzones); 209 } 210 211 /* Private. */ 212 213 static void 214 res_dprintf(const char *fmt, ...) { 215 va_list ap; 216 217 va_start(ap, fmt); 218 fputs(";; res_nupdate: ", stderr); 219 vfprintf(stderr, fmt, ap); 220 fputc('\n', stderr); 221 va_end(ap); 222 } 223