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