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 18 /*! \file 19 * \brief 20 * Based on the Dynamic DNS reference implementation by Viraj Bais 21 * <viraj_bais@ccm.fm.intel.com> 22 */ 23 24 #include "port_before.h" 25 26 #include <sys/param.h> 27 #include <sys/socket.h> 28 #include <sys/time.h> 29 30 #include <netinet/in.h> 31 #include <arpa/inet.h> 32 #include <arpa/nameser.h> 33 34 #include <errno.h> 35 #include <limits.h> 36 #include <netdb.h> 37 #include <res_update.h> 38 #include <stdarg.h> 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <string.h> 42 43 #include <isc/list.h> 44 #include <resolv.h> 45 46 #include "port_after.h" 47 #include "res_private.h" 48 49 /*% 50 * Separate a linked list of records into groups so that all records 51 * in a group will belong to a single zone on the nameserver. 52 * Create a dynamic update packet for each zone and send it to the 53 * nameservers for that zone, and await answer. 54 * Abort if error occurs in updating any zone. 55 * Return the number of zones updated on success, < 0 on error. 56 * 57 * On error, caller must deal with the unsynchronized zones 58 * eg. an A record might have been successfully added to the forward 59 * zone but the corresponding PTR record would be missing if error 60 * was encountered while updating the reverse zone. 61 */ 62 63 struct zonegrp { 64 char z_origin[MAXDNAME]; 65 ns_class z_class; 66 union res_sockaddr_union z_nsaddrs[MAXNS]; 67 int z_nscount; 68 int z_flags; 69 LIST(ns_updrec) z_rrlist; 70 LINK(struct zonegrp) z_link; 71 }; 72 73 #define ZG_F_ZONESECTADDED 0x0001 74 75 /* Forward. */ 76 77 static void res_dprintf(const char *, ...) ISC_FORMAT_PRINTF(1, 2); 78 79 /* Macros. */ 80 81 #define DPRINTF(x) do {\ 82 int save_errno = errno; \ 83 if ((statp->options & RES_DEBUG) != 0U) res_dprintf x; \ 84 errno = save_errno; \ 85 } while (0) 86 87 /* Public. */ 88 89 int 90 res_nupdate(res_state statp, ns_updrec *rrecp_in, ns_tsig_key *key) { 91 ns_updrec *rrecp; 92 u_char answer[PACKETSZ]; 93 u_char *packet; 94 struct zonegrp *zptr, tgrp; 95 LIST(struct zonegrp) zgrps; 96 int nzones = 0, nscount = 0, n; 97 union res_sockaddr_union nsaddrs[MAXNS]; 98 99 packet = malloc(NS_MAXMSG); 100 if (packet == NULL) { 101 DPRINTF(("malloc failed")); 102 return (0); 103 } 104 /* Thread all of the updates onto a list of groups. */ 105 INIT_LIST(zgrps); 106 memset(&tgrp, 0, sizeof (tgrp)); 107 for (rrecp = rrecp_in; rrecp; 108 rrecp = LINKED(rrecp, r_link) ? NEXT(rrecp, r_link) : NULL) { 109 int nscnt; 110 /* Find the origin for it if there is one. */ 111 tgrp.z_class = rrecp->r_class; 112 nscnt = res_findzonecut2(statp, rrecp->r_dname, tgrp.z_class, 113 RES_EXHAUSTIVE, tgrp.z_origin, 114 sizeof tgrp.z_origin, 115 tgrp.z_nsaddrs, MAXNS); 116 if (nscnt <= 0) { 117 DPRINTF(("res_findzonecut failed (%d)", nscnt)); 118 goto done; 119 } 120 tgrp.z_nscount = nscnt; 121 /* Find the group for it if there is one. */ 122 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) 123 if (ns_samename(tgrp.z_origin, zptr->z_origin) == 1 && 124 tgrp.z_class == zptr->z_class) 125 break; 126 /* Make a group for it if there isn't one. */ 127 if (zptr == NULL) { 128 zptr = malloc(sizeof *zptr); 129 if (zptr == NULL) { 130 DPRINTF(("malloc failed")); 131 goto done; 132 } 133 *zptr = tgrp; 134 zptr->z_flags = 0; 135 INIT_LINK(zptr, z_link); 136 INIT_LIST(zptr->z_rrlist); 137 APPEND(zgrps, zptr, z_link); 138 } 139 /* Thread this rrecp onto the right group. */ 140 APPEND(zptr->z_rrlist, rrecp, r_glink); 141 } 142 143 for (zptr = HEAD(zgrps); zptr != NULL; zptr = NEXT(zptr, z_link)) { 144 /* Construct zone section and prepend it. */ 145 rrecp = res_mkupdrec(ns_s_zn, zptr->z_origin, 146 zptr->z_class, ns_t_soa, 0); 147 if (rrecp == NULL) { 148 DPRINTF(("res_mkupdrec failed")); 149 goto done; 150 } 151 PREPEND(zptr->z_rrlist, rrecp, r_glink); 152 zptr->z_flags |= ZG_F_ZONESECTADDED; 153 154 /* Marshall the update message. */ 155 n = res_nmkupdate(statp, HEAD(zptr->z_rrlist), 156 packet, NS_MAXMSG); 157 DPRINTF(("res_mkupdate -> %d", n)); 158 if (n < 0) 159 goto done; 160 161 /* Temporarily replace the resolver's nameserver set. */ 162 nscount = res_getservers(statp, nsaddrs, MAXNS); 163 res_setservers(statp, zptr->z_nsaddrs, zptr->z_nscount); 164 165 /* Send the update and remember the result. */ 166 if (key != NULL) 167 n = res_nsendsigned(statp, packet, n, key, 168 answer, sizeof answer); 169 else 170 n = res_nsend(statp, packet, n, answer, sizeof answer); 171 if (n < 0) { 172 DPRINTF(("res_nsend: send error, n=%d (%s)\n", 173 n, strerror(errno))); 174 goto done; 175 } 176 if (((HEADER *)answer)->rcode == NOERROR) 177 nzones++; 178 179 /* Restore resolver's nameserver set. */ 180 res_setservers(statp, nsaddrs, nscount); 181 nscount = 0; 182 } 183 done: 184 while (!EMPTY(zgrps)) { 185 zptr = HEAD(zgrps); 186 if ((zptr->z_flags & ZG_F_ZONESECTADDED) != 0) 187 res_freeupdrec(HEAD(zptr->z_rrlist)); 188 UNLINK(zgrps, zptr, z_link); 189 free(zptr); 190 } 191 if (nscount != 0) 192 res_setservers(statp, nsaddrs, nscount); 193 194 free(packet); 195 return (nzones); 196 } 197 198 /* Private. */ 199 200 static void 201 res_dprintf(const char *fmt, ...) { 202 va_list ap; 203 204 va_start(ap, fmt); 205 fputs(";; res_nupdate: ", stderr); 206 vfprintf(stderr, fmt, ap); 207 fputc('\n', stderr); 208 va_end(ap); 209 } 210