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
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
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
39 #include <rpcsvc/yp.h>
40 #include <rpcsvc/yppasswd.h>
41 #include <rpcsvc/ypxfrd.h>
42 #include <sys/types.h>
45 #include <sys/socket.h>
46 #include <netinet/in.h>
47 #include <arpa/inet.h>
49 #include <sys/fcntl.h>
52 #include <sys/param.h>
53 #include "yp_extern.h"
61 const char *yp_procs[] = {
64 "ypoldproc_domain_nonack",
71 "badproc1", /* placeholder */
72 "badproc2", /* placeholder */
73 "badproc3", /* placeholder */
78 "ypproc_domain_nonack",
93 struct securenet *next;
96 struct securenet *securenets;
98 #define LINEBUFSZ 1024
101 int hosts_ctl(char *, char *, char *, char *);
105 * Read /var/yp/securenets file and initialize the securenets
106 * list. If the file doesn't exist, we set up a dummy entry that
107 * allows all hosts to connect.
110 load_securenets(void)
113 char path[MAXPATHLEN + 2];
114 char linebuf[1024 + 2];
115 struct securenet *tmp;
118 * If securenets is not NULL, we are being called to reload
119 * the list; free the existing list before re-reading the
123 tmp = securenets->next;
128 snprintf(path, MAXPATHLEN, "%s/securenets", yp_dir);
130 if ((fp = fopen(path, "r")) == NULL) {
131 if (errno == ENOENT) {
132 securenets = (struct securenet *)malloc(sizeof(struct securenet));
133 securenets->net.s_addr = INADDR_ANY;
134 securenets->mask.s_addr = INADDR_ANY;
135 securenets->next = NULL;
138 yp_error("fopen(%s) failed: %s", path, strerror(errno));
145 while (fgets(linebuf, LINEBUFSZ, fp)) {
146 char addr1[20], addr2[20];
148 if ((linebuf[0] == '#')
149 || (strspn(linebuf, " \t\r\n") == strlen(linebuf)))
151 if (sscanf(linebuf, "%s %s", addr1, addr2) < 2) {
152 yp_error("badly formatted securenets entry: %s",
157 tmp = (struct securenet *)malloc(sizeof(struct securenet));
159 if (!inet_aton((char *)&addr1, (struct in_addr *)&tmp->net)) {
160 yp_error("badly formatted securenets entry: %s", addr1);
165 if (!inet_aton((char *)&addr2, (struct in_addr *)&tmp->mask)) {
166 yp_error("badly formatted securenets entry: %s", addr2);
171 tmp->next = securenets;
180 * Access control functions.
182 * yp_access() checks the mapname and client host address and watches for
183 * the following things:
185 * - If the client is referencing one of the master.passwd.* or shadow.* maps,
186 * it must be using a privileged port to make its RPC to us. If it is, then
187 * we can assume that the caller is root and allow the RPC to succeed. If it
188 * isn't access is denied.
190 * - The client's IP address is checked against the securenets rules.
191 * There are two kinds of securenets support: the built-in support,
192 * which is very simple and depends on the presence of a
193 * /var/yp/securenets file, and tcp-wrapper support, which requires
194 * Wietse Venema's libwrap.a and tcpd.h. (Since the tcp-wrapper
195 * package does not ship with FreeBSD, we use the built-in support
196 * by default. Users can recompile the server with the tcp-wrapper library
197 * if they already have it installed and want to use hosts.allow and
198 * hosts.deny to control access instead of having a separate securenets
201 * If no /var/yp/securenets file is present, the host access checks
202 * are bypassed and all hosts are allowed to connect.
204 * The yp_validdomain() function checks the domain specified by the caller
205 * to make sure it's actually served by this server. This is more a sanity
206 * check than an a security check, but this seems to be the best place for
212 yp_access(const char *map, const char *domain, const struct svc_req *rqstp)
215 yp_access(const char *map, const struct svc_req *rqstp)
218 struct sockaddr_in *rqhost;
219 int status_securenets = 0;
223 static unsigned long oldaddr = 0;
224 struct securenet *tmp;
225 const char *yp_procedure = NULL;
228 if (rqstp->rq_prog != YPPASSWDPROG && rqstp->rq_prog != YPPROG) {
229 snprintf(procbuf, sizeof(procbuf), "#%lu/#%lu",
230 (unsigned long)rqstp->rq_prog,
231 (unsigned long)rqstp->rq_proc);
232 yp_procedure = (char *)&procbuf;
234 yp_procedure = rqstp->rq_prog == YPPASSWDPROG ?
235 "yppasswdprog_update" :
236 yp_procs[rqstp->rq_proc + (12 * (rqstp->rq_vers - 1))];
239 rqhost = svc_getcaller(rqstp->rq_xprt);
242 yp_error("procedure %s called from %s:%d", yp_procedure,
243 inet_ntoa(rqhost->sin_addr),
244 ntohs(rqhost->sin_port));
246 yp_error("client is referencing map \"%s\".", map);
249 /* Check the map name if one was supplied. */
251 if (strchr(map, '/')) {
252 yp_error("embedded slash in map name \"%s\" -- \
253 possible spoof attempt from %s:%d",
254 map, inet_ntoa(rqhost->sin_addr),
255 ntohs(rqhost->sin_port));
259 if ((yp_testflag((char *)map, (char *)domain, YP_SECURE) ||
261 if ((strstr(map, "master.passwd.") || strstr(map, "shadow.") ||
263 (rqstp->rq_prog == YPPROG &&
264 rqstp->rq_proc == YPPROC_XFR) ||
265 (rqstp->rq_prog == YPXFRD_FREEBSD_PROG &&
266 rqstp->rq_proc == YPXFRD_GETMAP)) &&
267 ntohs(rqhost->sin_port) >= IPPORT_RESERVED) {
268 yp_error("access to %s denied -- client %s:%d \
269 not privileged", map, inet_ntoa(rqhost->sin_addr), ntohs(rqhost->sin_port));
275 status_tcpwrap = hosts_ctl("ypserv", STRING_UNKNOWN,
276 inet_ntoa(rqhost->sin_addr), "");
280 if (((rqhost->sin_addr.s_addr & ~tmp->mask.s_addr)
281 | tmp->net.s_addr) == rqhost->sin_addr.s_addr) {
282 status_securenets = 1;
289 if (status_securenets == 0 || status_tcpwrap == 0) {
291 if (status_securenets == 0) {
294 * One of the following two events occurred:
296 * (1) The /var/yp/securenets exists and the remote host does not
297 * match any of the networks specified in it.
298 * (2) The hosts.allow file has denied access and TCP_WRAPPER is
301 * In either case deny access.
303 if (rqhost->sin_addr.s_addr != oldaddr) {
304 yp_error("connect from %s:%d to procedure %s refused",
305 inet_ntoa(rqhost->sin_addr),
306 ntohs(rqhost->sin_port),
308 oldaddr = rqhost->sin_addr.s_addr;
317 yp_validdomain(const char *domain)
320 char dompath[MAXPATHLEN + 2];
322 if (domain == NULL || strstr(domain, "binding") ||
323 !strcmp(domain, ".") || !strcmp(domain, "..") ||
324 strchr(domain, '/') || strlen(domain) > YPMAXDOMAIN)
327 snprintf(dompath, sizeof(dompath), "%s/%s", yp_dir, domain);
329 if (stat(dompath, &statbuf) < 0 || !S_ISDIR(statbuf.st_mode))