xref: /freebsd/usr.sbin/rpc.ypxfrd/ypxfrd_main.c (revision 84b3c4547afa496b37e86c5e649e99237c8afc6e)
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 "ypxfrd.h"
39 #include <err.h>
40 #include <fcntl.h>
41 #include <paths.h>
42 #include <stdio.h>
43 #include <stdlib.h> /* getenv, exit */
44 #include <unistd.h>
45 #include <rpc/pmap_clnt.h> /* for pmap_unset */
46 #include <rpc/rpc_com.h>
47 #include <string.h> /* strcmp */
48 #include <signal.h>
49 #include <sys/ttycom.h> /* TIOCNOTTY */
50 #ifdef __cplusplus
51 #include <sysent.h> /* getdtablesize, open */
52 #endif /* __cplusplus */
53 #include <memory.h>
54 #include <sys/socket.h>
55 #include <netinet/in.h>
56 #include <syslog.h>
57 #include "ypxfrd_extern.h"
58 #include <sys/wait.h>
59 #include <errno.h>
60 
61 #ifndef SIG_PF
62 #define	SIG_PF void(*)(int)
63 #endif
64 
65 #ifdef DEBUG
66 #define	RPC_SVC_FG
67 #endif
68 
69 #define	_RPCSVC_CLOSEDOWN 120
70 int _rpcpmstart;		/* Started by a port monitor ? */
71 static int _rpcfdtype;
72 		 /* Whether Stream or Datagram ? */
73 	/* States a server can be in wrt request */
74 
75 #define	_IDLE 0
76 #define	_SERVED 1
77 #define	_SERVING 2
78 
79 extern int _rpcsvcstate;	 /* Set when a request is serviced */
80 
81 char *progname = "rpc.ypxfrd";
82 char *yp_dir = "/var/yp/";
83 
84 static void
85 _msgout(char *msg)
86 {
87 #ifdef RPC_SVC_FG
88 	if (_rpcpmstart)
89 		syslog(LOG_ERR, "%s", msg);
90 	else
91 		warnx("%s", msg);
92 #else
93 	syslog(LOG_ERR, "%s", msg);
94 #endif
95 }
96 
97 static void
98 closedown(int sig)
99 {
100 	if (_rpcsvcstate == _IDLE) {
101 		extern fd_set svc_fdset;
102 		static int size;
103 		int i, openfd;
104 
105 		if (_rpcfdtype == SOCK_DGRAM)
106 			exit(0);
107 		if (size == 0) {
108 			size = getdtablesize();
109 		}
110 		for (i = 0, openfd = 0; i < size && openfd < 2; i++)
111 			if (FD_ISSET(i, &svc_fdset))
112 				openfd++;
113 		if (openfd <= 1)
114 			exit(0);
115 	}
116 	if (_rpcsvcstate == _SERVED)
117 		_rpcsvcstate = _IDLE;
118 
119 	(void) signal(SIGALRM, (SIG_PF) closedown);
120 	(void) alarm(_RPCSVC_CLOSEDOWN/2);
121 }
122 
123 
124 static void
125 ypxfrd_svc_run(void)
126 {
127 #ifdef FD_SETSIZE
128 	fd_set readfds;
129 #else
130 	int readfds;
131 #endif /* def FD_SETSIZE */
132 	extern int forked;
133 	int pid;
134 	int fd_setsize = _rpc_dtablesize();
135 
136 	/* Establish the identity of the parent ypserv process. */
137 	pid = getpid();
138 
139 	for (;;) {
140 #ifdef FD_SETSIZE
141 		readfds = svc_fdset;
142 #else
143 		readfds = svc_fds;
144 #endif /* def FD_SETSIZE */
145 		switch (select(fd_setsize, &readfds, NULL, NULL,
146 			       (struct timeval *)0)) {
147 		case -1:
148 			if (errno == EINTR) {
149 				continue;
150 			}
151 			warn("svc_run: - select failed");
152 			return;
153 		case 0:
154 			continue;
155 		default:
156 			svc_getreqset(&readfds);
157 			if (forked && pid != getpid())
158 				exit(0);
159 		}
160 	}
161 }
162 
163 static void reaper(int sig)
164 {
165 	int			status;
166 	int			saved_errno;
167 
168 	saved_errno = errno;
169 
170 	if (sig == SIGHUP) {
171 		load_securenets();
172 		errno = saved_errno;
173 		return;
174 	}
175 
176 	if (sig == SIGCHLD) {
177 		while (wait3(&status, WNOHANG, NULL) > 0)
178 			children--;
179 	} else {
180 		(void) pmap_unset(YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS);
181 		exit(0);
182 	}
183 
184 	errno = saved_errno;
185 	return;
186 }
187 
188 void
189 usage(void)
190 {
191 	fprintf(stderr, "usage: rpc.ypxfrd [-p path]\n");
192 	exit(0);
193 }
194 
195 int
196 main(int argc, char *argv[])
197 {
198 	register SVCXPRT *transp = NULL;
199 	int sock;
200 	int proto = 0;
201 	struct sockaddr_in saddr;
202 	int asize = sizeof (saddr);
203 	int ch;
204 
205 	while ((ch = getopt(argc, argv, "p:h")) != -1) {
206 		switch (ch) {
207 		case 'p':
208 			yp_dir = optarg;
209 			break;
210 		default:
211 			usage();
212 			break;
213 		}
214 	}
215 
216 	load_securenets();
217 
218 	if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
219 		int ssize = sizeof (int);
220 
221 		if (saddr.sin_family != AF_INET)
222 			exit(1);
223 		if (getsockopt(0, SOL_SOCKET, SO_TYPE,
224 				(char *)&_rpcfdtype, &ssize) == -1)
225 			exit(1);
226 		sock = 0;
227 		_rpcpmstart = 1;
228 		proto = 0;
229 		openlog("rpc.ypxfrd", LOG_PID, LOG_DAEMON);
230 	} else {
231 #ifndef RPC_SVC_FG
232 		int size;
233 		int pid, i;
234 
235 		pid = fork();
236 		if (pid < 0)
237 			err(1, "fork");
238 		if (pid)
239 			exit(0);
240 		size = getdtablesize();
241 		for (i = 0; i < size; i++)
242 			(void) close(i);
243 		i = open(_PATH_CONSOLE, 2);
244 		(void) dup2(i, 1);
245 		(void) dup2(i, 2);
246 		i = open(_PATH_TTY, 2);
247 		if (i >= 0) {
248 			(void) ioctl(i, TIOCNOTTY, (char *)NULL);
249 			(void) close(i);
250 		}
251 		openlog("rpc.ypxfrd", LOG_PID, LOG_DAEMON);
252 #endif
253 		sock = RPC_ANYSOCK;
254 		(void) pmap_unset(YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS);
255 	}
256 
257 	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
258 		transp = svcudp_create(sock);
259 		if (transp == NULL) {
260 			_msgout("cannot create udp service.");
261 			exit(1);
262 		}
263 		if (!_rpcpmstart)
264 			proto = IPPROTO_UDP;
265 		if (!svc_register(transp, YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, ypxfrd_freebsd_prog_1, proto)) {
266 			_msgout("unable to register (YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, udp).");
267 			exit(1);
268 		}
269 	}
270 
271 	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
272 		transp = svctcp_create(sock, 0, 0);
273 		if (transp == NULL) {
274 			_msgout("cannot create tcp service.");
275 			exit(1);
276 		}
277 		if (!_rpcpmstart)
278 			proto = IPPROTO_TCP;
279 		if (!svc_register(transp, YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, ypxfrd_freebsd_prog_1, proto)) {
280 			_msgout("unable to register (YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, tcp).");
281 			exit(1);
282 		}
283 	}
284 
285 	if (transp == (SVCXPRT *)NULL) {
286 		_msgout("could not create a handle");
287 		exit(1);
288 	}
289 	if (_rpcpmstart) {
290 		(void) signal(SIGALRM, (SIG_PF) closedown);
291 		(void) alarm(_RPCSVC_CLOSEDOWN/2);
292 	}
293 
294 	(void) signal(SIGPIPE, SIG_IGN);
295 	(void) signal(SIGCHLD, (SIG_PF) reaper);
296 	(void) signal(SIGTERM, (SIG_PF) reaper);
297 	(void) signal(SIGINT, (SIG_PF) reaper);
298 	(void) signal(SIGHUP, (SIG_PF) reaper);
299 
300 	ypxfrd_svc_run();
301 	_msgout("svc_run returned");
302 	exit(1);
303 	/* NOTREACHED */
304 }
305