1 /*
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 1995, 1996
5  *	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Bill Paul.
18  * 4. Neither the name of the author nor the names of any co-contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/param.h>
39 #include <sys/ioctl.h>
40 #include <sys/stat.h>
41 #include <sys/socket.h>
42 #include <sys/time.h>
43 #include <sys/resource.h>
44 #include <netinet/in.h>
45 
46 #include <err.h>
47 #include <errno.h>
48 #include <fcntl.h>
49 #include <memory.h>
50 #include <signal.h>
51 #include <stdio.h>
52 #include <stdlib.h> /* getenv, exit */
53 #include <string.h> /* strcmp */
54 #include <syslog.h>
55 #include <unistd.h>
56 
57 #include <rpc/rpc.h>
58 #include <rpc/rpc_com.h>
59 #include <rpc/pmap_clnt.h> /* for pmap_unset */
60 #include <rpcsvc/yp.h>
61 #include <rpcsvc/ypclnt.h>
62 
63 #include "yppasswd.h"
64 #include "yppasswdd_extern.h"
65 #include "yppasswd_private.h"
66 #include "ypxfr_extern.h"
67 #include "yp_extern.h"
68 
69 #ifndef SIG_PF
70 #define	SIG_PF void(*)(int)
71 #endif
72 
73 #ifdef DEBUG
74 #define	RPC_SVC_FG
75 #endif
76 
77 #define	_RPCSVC_CLOSEDOWN 120
78 int _rpcpmstart = 0;		/* Started by a port monitor ? */
79 static int _rpcfdtype;
80 		 /* Whether Stream or Datagram ? */
81 	/* States a server can be in wrt request */
82 
83 #define	_IDLE 0
84 #define	_SERVED 1
85 #define	_SERVING 2
86 
87 static char _localhost[] = "localhost";
88 static char _passwd_byname[] = "passwd.byname";
89 extern int _rpcsvcstate;	 /* Set when a request is serviced */
90 static char _progname[] = "rpc.yppasswdd";
91 char *progname = _progname;
92 static char _yp_dir[] = _PATH_YP;
93 char *yp_dir = _yp_dir;
94 static char _passfile_default[] = _PATH_YP "master.passwd";
95 char *passfile_default = _passfile_default;
96 char *passfile;
97 char *yppasswd_domain = NULL;
98 int no_chsh = 0;
99 int no_chfn = 0;
100 int allow_additions = 0;
101 int multidomain = 0;
102 int verbose = 0;
103 int resvport = 1;
104 int inplace = 0;
105 char sockname[] = YP_SOCKNAME;
106 
107 static void
108 terminate(int sig __unused)
109 {
110 	rpcb_unset(YPPASSWDPROG, YPPASSWDVERS, NULL);
111 	rpcb_unset(MASTER_YPPASSWDPROG, MASTER_YPPASSWDVERS, NULL);
112 	unlink(sockname);
113 	exit(0);
114 }
115 
116 static void
117 reload(int sig __unused)
118 {
119 	load_securenets();
120 }
121 
122 static void
123 closedown(int sig __unused)
124 {
125 	if (_rpcsvcstate == _IDLE) {
126 		extern fd_set svc_fdset;
127 		static int size;
128 		int i, openfd;
129 
130 		if (_rpcfdtype == SOCK_DGRAM) {
131 			unlink(sockname);
132 			exit(0);
133 		}
134 		if (size == 0) {
135 			size = getdtablesize();
136 		}
137 		for (i = 0, openfd = 0; i < size && openfd < 2; i++)
138 			if (FD_ISSET(i, &svc_fdset))
139 				openfd++;
140 		if (openfd <= 1) {
141 			unlink(sockname);
142 			exit(0);
143 		}
144 	}
145 	if (_rpcsvcstate == _SERVED)
146 		_rpcsvcstate = _IDLE;
147 
148 	(void) signal(SIGALRM, (SIG_PF) closedown);
149 	(void) alarm(_RPCSVC_CLOSEDOWN/2);
150 }
151 
152 static void
153 usage(void)
154 {
155 	fprintf(stderr, "%s\n%s\n",
156 "usage: rpc.yppasswdd [-t master.passwd file] [-d domain] [-p path] [-s]",
157 "                     [-f] [-m] [-i] [-a] [-v] [-u] [-h]");
158 	exit(1);
159 }
160 
161 int
162 main(int argc, char *argv[])
163 {
164 	struct rlimit rlim;
165 	SVCXPRT *transp = NULL;
166 	struct sockaddr_in saddr;
167 	socklen_t asize = sizeof (saddr);
168 	struct netconfig *nconf;
169 	struct sigaction sa;
170 	void *localhandle;
171 	int ch;
172 	char *mastername;
173 	char myname[MAXHOSTNAMELEN + 2];
174 	int maxrec = RPC_MAXDATASIZE;
175 
176 	extern int debug;
177 
178 	debug = 1;
179 
180 	while ((ch = getopt(argc, argv, "t:d:p:sfamuivh")) != -1) {
181 		switch (ch) {
182 		case 't':
183 			passfile_default = optarg;
184 			break;
185 		case 'd':
186 			yppasswd_domain = optarg;
187 			break;
188 		case 's':
189 			no_chsh++;
190 			break;
191 		case 'f':
192 			no_chfn++;
193 			break;
194 		case 'p':
195 			yp_dir = optarg;
196 			break;
197 		case 'a':
198 			allow_additions++;
199 			break;
200 		case 'm':
201 			multidomain++;
202 			break;
203 		case 'i':
204 			inplace++;
205 			break;
206 		case 'v':
207 			verbose++;
208 			break;
209 		case 'u':
210 			resvport = 0;
211 			break;
212 		default:
213 		case 'h':
214 			usage();
215 			break;
216 		}
217 	}
218 
219 	if (yppasswd_domain == NULL) {
220 		if (yp_get_default_domain(&yppasswd_domain)) {
221 			yp_error("no domain specified and system domain \
222 name isn't set -- aborting");
223 		usage();
224 		}
225 	}
226 
227 	load_securenets();
228 
229 	if (getrpcport(_localhost, YPPROG, YPVERS, IPPROTO_UDP) <= 0) {
230 		yp_error("no ypserv processes registered with local portmap");
231 		yp_error("this host is not an NIS server -- aborting");
232 		exit(1);
233 	}
234 
235 	if ((mastername = ypxfr_get_master(yppasswd_domain,
236 		 _passwd_byname, _localhost, 0)) == NULL) {
237 		yp_error("can't get name of NIS master server for domain %s",
238 			 				yppasswd_domain);
239 		exit(1);
240 	}
241 
242 	if (gethostname((char *)&myname, sizeof(myname)) == -1) {
243 		yp_error("can't get local hostname: %s", strerror(errno));
244 		exit(1);
245 	}
246 
247 	if (strncasecmp(mastername, (char *)&myname, sizeof(myname))) {
248 		yp_error("master of %s is %s, but we are %s",
249 			"passwd.byname", mastername, myname);
250 		yp_error("this host is not the NIS master server for \
251 the %s domain -- aborting", yppasswd_domain);
252 		exit(1);
253 	}
254 
255 	debug = 0;
256 
257 	if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
258 		socklen_t ssize = sizeof (int);
259 		if (saddr.sin_family != AF_INET)
260 			exit(1);
261 		if (getsockopt(0, SOL_SOCKET, SO_TYPE,
262 		    (char *)&_rpcfdtype, &ssize) == -1)
263 			exit(1);
264 		_rpcpmstart = 1;
265 	}
266 
267 	if (!debug && _rpcpmstart == 0) {
268 		if (daemon(0,0)) {
269 			err(1,"cannot fork");
270 		}
271 	}
272 	openlog("rpc.yppasswdd", LOG_PID, LOG_DAEMON);
273 	memset(&sa, 0, sizeof(sa));
274 	sa.sa_flags = SA_NOCLDWAIT;
275 	sigaction(SIGCHLD, &sa, NULL);
276 
277 	rpcb_unset(YPPASSWDPROG, YPPASSWDVERS, NULL);
278 	rpcb_unset(MASTER_YPPASSWDPROG, MASTER_YPPASSWDVERS, NULL);
279 
280 	rpc_control(RPC_SVC_CONNMAXREC_SET, &maxrec);
281 
282 	if (svc_create(yppasswdprog_1, YPPASSWDPROG, YPPASSWDVERS, "netpath") == 0) {
283 		yp_error("cannot create yppasswd service.");
284 		exit(1);
285 	}
286 	if (svc_create(master_yppasswdprog_1, MASTER_YPPASSWDPROG,
287 	    MASTER_YPPASSWDVERS, "netpath") == 0) {
288 		yp_error("cannot create master_yppasswd service.");
289 		exit(1);
290 	}
291 
292 	nconf = NULL;
293 	localhandle = setnetconfig();
294 	while ((nconf = getnetconfig(localhandle)) != NULL) {
295 		if (nconf->nc_protofmly != NULL &&
296 		    strcmp(nconf->nc_protofmly, NC_LOOPBACK) == 0)
297 			break;
298 	}
299 	if (nconf == NULL) {
300 		yp_error("getnetconfigent unix: %s", nc_sperror());
301 		exit(1);
302 	}
303 	unlink(sockname);
304 	transp = svcunix_create(RPC_ANYSOCK, 0, 0, sockname);
305 	if (transp == NULL) {
306 		yp_error("cannot create AF_LOCAL service.");
307 		exit(1);
308 	}
309 	if (!svc_reg(transp, MASTER_YPPASSWDPROG, MASTER_YPPASSWDVERS,
310 	    master_yppasswdprog_1, nconf)) {
311 		yp_error("unable to register (MASTER_YPPASSWDPROG, \
312 		    MASTER_YPPASSWDVERS, unix).");
313 		exit(1);
314 	}
315 	endnetconfig(localhandle);
316 
317 	/* Only root may connect() to the AF_UNIX link. */
318 	if (chmod(sockname, 0))
319 		err(1, "chmod of %s failed", sockname);
320 
321 	if (transp == (SVCXPRT *)NULL) {
322 		yp_error("could not create a handle");
323 		exit(1);
324 	}
325 	if (_rpcpmstart) {
326 		(void) signal(SIGALRM, (SIG_PF) closedown);
327 		(void) alarm(_RPCSVC_CLOSEDOWN/2);
328 	}
329 
330 	/* Unlimited resource limits. */
331 	rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
332 	(void)setrlimit(RLIMIT_CPU, &rlim);
333 	(void)setrlimit(RLIMIT_FSIZE, &rlim);
334 	(void)setrlimit(RLIMIT_STACK, &rlim);
335 	(void)setrlimit(RLIMIT_DATA, &rlim);
336 	(void)setrlimit(RLIMIT_RSS, &rlim);
337 
338 	/* Don't drop core (not really necessary, but GP's). */
339 	rlim.rlim_cur = rlim.rlim_max = 0;
340 	(void)setrlimit(RLIMIT_CORE, &rlim);
341 
342 	/* Turn off signals. */
343 	(void)signal(SIGALRM, SIG_IGN);
344 	(void)signal(SIGHUP, (SIG_PF) reload);
345 	(void)signal(SIGINT, SIG_IGN);
346 	(void)signal(SIGPIPE, SIG_IGN);
347 	(void)signal(SIGQUIT, SIG_IGN);
348 	(void)signal(SIGTERM, (SIG_PF) terminate);
349 
350 	svc_run();
351 	yp_error("svc_run returned");
352 	exit(1);
353 	/* NOTREACHED */
354 }
355