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 $";
3 #endif /* not lint */
4
5 /*-
6 * SPDX-License-Identifier: ISC
7 *
8 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
9 * Copyright (c) 1996-1999 by Internet Software Consortium.
10 *
11 * Permission to use, copy, modify, and distribute this software for any
12 * purpose with or without fee is hereby granted, provided that the above
13 * copyright notice and this permission notice appear in all copies.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
16 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
17 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
18 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
19 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
20 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
21 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
22 */
23
24 /*! \file
25 * \brief
26 * Based on the Dynamic DNS reference implementation by Viraj Bais
27 * <[email protected]>
28 */
29
30 #include <sys/cdefs.h>
31 __FBSDID("$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
res_nupdate(res_state statp,ns_updrec * rrecp_in,ns_tsig_key * key)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
res_dprintf(const char * fmt,...)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