Pre-2.0 release, MFC 63 - HAMMER I/O error handling and catastrophic
[dragonfly.git] / usr.sbin / ypserv / yp_access.c
blob604655d33f058b613c96b0223849f0034023b80c
1 /*
2 * Copyright (c) 1995
3 * Bill Paul <wpaul@ctr.columbia.edu>. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by Bill Paul.
16 * 4. Neither the name of the author nor the names of any co-contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
32 * $FreeBSD: src/usr.sbin/ypserv/yp_access.c,v 1.17.2.1 2002/02/15 00:47:00 des Exp $
33 * $DragonFly: src/usr.sbin/ypserv/yp_access.c,v 1.5 2006/06/13 12:38:37 corecode Exp $
36 #include <stdlib.h>
37 #include <rpc/rpc.h>
38 #include <rpcsvc/yp.h>
39 #include <rpcsvc/yppasswd.h>
40 #include <rpcsvc/ypxfrd.h>
41 #include <sys/types.h>
42 #include <limits.h>
43 #include <db.h>
44 #include <sys/socket.h>
45 #include <netinet/in.h>
46 #include <arpa/inet.h>
47 #include <sys/stat.h>
48 #include <sys/fcntl.h>
49 #include <paths.h>
50 #include <errno.h>
51 #include <sys/param.h>
52 #include "yp_extern.h"
53 #ifdef TCP_WRAPPER
54 #include "tcpd.h"
55 #endif
57 extern int debug;
59 /* NIS v1 */
60 char *yp_procs[] = { "ypoldproc_null",
61 "ypoldproc_domain",
62 "ypoldproc_domain_nonack",
63 "ypoldproc_match",
64 "ypoldproc_first",
65 "ypoldproc_next",
66 "ypoldproc_poll",
67 "ypoldproc_push",
68 "ypoldproc_get",
69 "badproc1", /* placeholder */
70 "badproc2", /* placeholder */
71 "badproc3", /* placeholder */
73 /* NIS v2 */
74 "ypproc_null",
75 "ypproc_domain",
76 "ypproc_domain_nonack",
77 "ypproc_match",
78 "ypproc_first",
79 "ypproc_next",
80 "ypproc_xfr",
81 "ypproc_clear",
82 "ypproc_all",
83 "ypproc_master",
84 "ypproc_order",
85 "ypproc_maplist"
88 struct securenet {
89 struct in_addr net;
90 struct in_addr mask;
91 struct securenet *next;
94 struct securenet *securenets;
96 #define LINEBUFSZ 1024
99 * Read /var/yp/securenets file and initialize the securenets
100 * list. If the file doesn't exist, we set up a dummy entry that
101 * allows all hosts to connect.
103 void
104 load_securenets(void)
106 FILE *fp;
107 char path[MAXPATHLEN + 2];
108 char linebuf[1024 + 2];
109 struct securenet *tmp;
112 * If securenets is not NULL, we are being called to reload
113 * the list; free the existing list before re-reading the
114 * securenets file.
116 while (securenets) {
117 tmp = securenets->next;
118 free(securenets);
119 securenets = tmp;
122 snprintf(path, MAXPATHLEN, "%s/securenets", yp_dir);
124 if ((fp = fopen(path, "r")) == NULL) {
125 if (errno == ENOENT) {
126 securenets = (struct securenet *)malloc(sizeof(struct securenet));
127 securenets->net.s_addr = INADDR_ANY;
128 securenets->mask.s_addr = INADDR_ANY;
129 securenets->next = NULL;
130 return;
131 } else {
132 yp_error("fopen(%s) failed: %s", path, strerror(errno));
133 exit(1);
137 securenets = NULL;
139 while (fgets(linebuf, LINEBUFSZ, fp)) {
140 char addr1[20], addr2[20];
142 if ((linebuf[0] == '#')
143 || (strspn(linebuf, " \t\r\n") == strlen(linebuf)))
144 continue;
145 if (sscanf(linebuf, "%s %s", addr1, addr2) < 2) {
146 yp_error("badly formatted securenets entry: %s",
147 linebuf);
148 continue;
151 tmp = (struct securenet *)malloc(sizeof(struct securenet));
153 if (!inet_aton((char *)&addr1, (struct in_addr *)&tmp->net)) {
154 yp_error("badly formatted securenets entry: %s", addr1);
155 free(tmp);
156 continue;
159 if (!inet_aton((char *)&addr2, (struct in_addr *)&tmp->mask)) {
160 yp_error("badly formatted securenets entry: %s", addr2);
161 free(tmp);
162 continue;
165 tmp->next = securenets;
166 securenets = tmp;
169 fclose(fp);
174 * Access control functions.
176 * yp_access() checks the mapname and client host address and watches for
177 * the following things:
179 * - If the client is referencing one of the master.passwd.* maps, it must
180 * be using a privileged port to make its RPC to us. If it is, then we can
181 * assume that the caller is root and allow the RPC to succeed. If it
182 * isn't access is denied.
184 * - The client's IP address is checked against the securenets rules.
185 * There are two kinds of securenets support: the built-in support,
186 * which is very simple and depends on the presence of a
187 * /var/yp/securenets file, and tcp-wrapper support, which requires
188 * Wietse Venema's libwrap.a and tcpd.h. (Since the tcp-wrapper
189 * package does not ship with FreeBSD, we use the built-in support
190 * by default. Users can recompile the server with the tcp-wrapper library
191 * if they already have it installed and want to use hosts.allow and
192 * hosts.deny to control access instead of having a separate securenets
193 * file.)
195 * If no /var/yp/securenets file is present, the host access checks
196 * are bypassed and all hosts are allowed to connect.
198 * The yp_validdomain() function checks the domain specified by the caller
199 * to make sure it's actually served by this server. This is more a sanity
200 * check than an a security check, but this seems to be the best place for
201 * it.
204 #ifdef DB_CACHE
206 yp_access(const char *map, const char *domain, const struct svc_req *rqstp)
207 #else
209 yp_access(const char *map, const struct svc_req *rqstp)
210 #endif
212 struct sockaddr_in *rqhost;
213 int status_securenets = 0;
214 #ifdef TCP_WRAPPER
215 int status_tcpwrap;
216 #endif
217 static unsigned long oldaddr = 0;
218 struct securenet *tmp;
219 char *yp_procedure = NULL;
220 char procbuf[50];
222 if (rqstp->rq_prog != YPPASSWDPROG && rqstp->rq_prog != YPPROG) {
223 snprintf(procbuf, sizeof(procbuf), "#%lu/#%lu", rqstp->rq_prog,
224 rqstp->rq_proc);
225 yp_procedure = (char *)&procbuf;
226 } else {
227 yp_procedure = rqstp->rq_prog == YPPASSWDPROG ?
228 "yppasswdprog_update" :
229 yp_procs[rqstp->rq_proc + (12 * (rqstp->rq_vers - 1))];
232 rqhost = svc_getcaller(rqstp->rq_xprt);
234 if (debug) {
235 yp_error("procedure %s called from %s:%d", yp_procedure,
236 inet_ntoa(rqhost->sin_addr),
237 ntohs(rqhost->sin_port));
238 if (map != NULL)
239 yp_error("client is referencing map \"%s\".", map);
242 /* Check the map name if one was supplied. */
243 if (map != NULL) {
244 if (strchr(map, '/')) {
245 yp_error("embedded slash in map name \"%s\" -- \
246 possible spoof attempt from %s:%d",
247 map, inet_ntoa(rqhost->sin_addr),
248 ntohs(rqhost->sin_port));
249 return(1);
251 #ifdef DB_CACHE
252 if ((yp_testflag((char *)map, (char *)domain, YP_SECURE) ||
253 #else
254 if ((strstr(map, "master.passwd.") ||
255 #endif
256 (rqstp->rq_prog == YPPROG &&
257 rqstp->rq_proc == YPPROC_XFR) ||
258 (rqstp->rq_prog == YPXFRD_FREEBSD_PROG &&
259 rqstp->rq_proc == YPXFRD_GETMAP)) &&
260 ntohs(rqhost->sin_port) >= IPPORT_RESERVED) {
261 yp_error("access to %s denied -- client %s:%d \
262 not privileged", map, inet_ntoa(rqhost->sin_addr), ntohs(rqhost->sin_port));
263 return(1);
267 #ifdef TCP_WRAPPER
268 status_tcpwrap = hosts_ctl("ypserv", STRING_UNKNOWN,
269 inet_ntoa(rqhost->sin_addr), "");
270 #endif
271 tmp = securenets;
272 while (tmp) {
273 if (((rqhost->sin_addr.s_addr & ~tmp->mask.s_addr)
274 | tmp->net.s_addr) == rqhost->sin_addr.s_addr) {
275 status_securenets = 1;
276 break;
278 tmp = tmp->next;
281 #ifdef TCP_WRAPPER
282 if (status_securenets == 0 || status_tcpwrap == 0) {
283 #else
284 if (status_securenets == 0) {
285 #endif
287 * One of the following two events occured:
289 * (1) The /var/yp/securenets exists and the remote host does not
290 * match any of the networks specified in it.
291 * (2) The hosts.allow file has denied access and TCP_WRAPPER is
292 * defined.
294 * In either case deny access.
296 if (rqhost->sin_addr.s_addr != oldaddr) {
297 yp_error("connect from %s:%d to procedure %s refused",
298 inet_ntoa(rqhost->sin_addr),
299 ntohs(rqhost->sin_port),
300 yp_procedure);
301 oldaddr = rqhost->sin_addr.s_addr;
303 return(1);
305 return(0);
310 yp_validdomain(const char *domain)
312 struct stat statbuf;
313 char dompath[MAXPATHLEN + 2];
315 if (domain == NULL || strstr(domain, "binding") ||
316 !strcmp(domain, ".") || !strcmp(domain, "..") ||
317 strchr(domain, '/') || strlen(domain) > YPMAXDOMAIN)
318 return(1);
320 snprintf(dompath, sizeof(dompath), "%s/%s", yp_dir, domain);
322 if (stat(dompath, &statbuf) < 0 || !S_ISDIR(statbuf.st_mode))
323 return(1);
326 return(0);