1#if !defined(lint) && !defined(SABER)
2static 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
72struct 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
86static 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
98int
99res_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
215static void
216res_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