xref: /freebsd/usr.sbin/rpc.ypxfrd/ypxfrd_main.c (revision d43fa8ef534ac87a16843d45264f56cf11e0fcbc)
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 int debug;
82 
83 char *progname = "rpc.ypxfrd";
84 char *yp_dir = "/var/yp/";
85 
86 static void
87 _msgout(char *msg)
88 {
89 #ifdef RPC_SVC_FG
90 	if (_rpcpmstart)
91 		syslog(LOG_ERR, "%s", msg);
92 	else
93 		warnx("%s", msg);
94 #else
95 	syslog(LOG_ERR, "%s", msg);
96 #endif
97 }
98 
99 static void
100 closedown(int sig)
101 {
102 	if (_rpcsvcstate == _IDLE) {
103 		extern fd_set svc_fdset;
104 		static int size;
105 		int i, openfd;
106 
107 		if (_rpcfdtype == SOCK_DGRAM)
108 			exit(0);
109 		if (size == 0) {
110 			size = getdtablesize();
111 		}
112 		for (i = 0, openfd = 0; i < size && openfd < 2; i++)
113 			if (FD_ISSET(i, &svc_fdset))
114 				openfd++;
115 		if (openfd <= 1)
116 			exit(0);
117 	}
118 	if (_rpcsvcstate == _SERVED)
119 		_rpcsvcstate = _IDLE;
120 
121 	(void) signal(SIGALRM, (SIG_PF) closedown);
122 	(void) alarm(_RPCSVC_CLOSEDOWN/2);
123 }
124 
125 
126 static void
127 ypxfrd_svc_run(void)
128 {
129 #ifdef FD_SETSIZE
130 	fd_set readfds;
131 #else
132 	int readfds;
133 #endif /* def FD_SETSIZE */
134 	extern int forked;
135 	int pid;
136 	int fd_setsize = _rpc_dtablesize();
137 
138 	/* Establish the identity of the parent ypserv process. */
139 	pid = getpid();
140 
141 	for (;;) {
142 #ifdef FD_SETSIZE
143 		readfds = svc_fdset;
144 #else
145 		readfds = svc_fds;
146 #endif /* def FD_SETSIZE */
147 		switch (select(fd_setsize, &readfds, NULL, NULL,
148 			       (struct timeval *)0)) {
149 		case -1:
150 			if (errno == EINTR) {
151 				continue;
152 			}
153 			warn("svc_run: - select failed");
154 			return;
155 		case 0:
156 			continue;
157 		default:
158 			svc_getreqset(&readfds);
159 			if (forked && pid != getpid())
160 				exit(0);
161 		}
162 	}
163 }
164 
165 static void reaper(int sig)
166 {
167 	int			status;
168 	int			saved_errno;
169 
170 	saved_errno = errno;
171 
172 	if (sig == SIGHUP) {
173 		load_securenets();
174 		errno = saved_errno;
175 		return;
176 	}
177 
178 	if (sig == SIGCHLD) {
179 		while (wait3(&status, WNOHANG, NULL) > 0)
180 			children--;
181 	} else {
182 		(void) pmap_unset(YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS);
183 		exit(0);
184 	}
185 
186 	errno = saved_errno;
187 	return;
188 }
189 
190 void
191 usage(void)
192 {
193 	fprintf(stderr, "usage: rpc.ypxfrd [-p path]\n");
194 	exit(0);
195 }
196 
197 int
198 main(int argc, char *argv[])
199 {
200 	register SVCXPRT *transp = NULL;
201 	int sock;
202 	int proto = 0;
203 	struct sockaddr_in saddr;
204 	int asize = sizeof (saddr);
205 	int ch;
206 
207 	while ((ch = getopt(argc, argv, "p:h")) != -1) {
208 		switch (ch) {
209 		case 'p':
210 			yp_dir = optarg;
211 			break;
212 		default:
213 			usage();
214 			break;
215 		}
216 	}
217 
218 	load_securenets();
219 
220 	if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
221 		int ssize = sizeof (int);
222 
223 		if (saddr.sin_family != AF_INET)
224 			exit(1);
225 		if (getsockopt(0, SOL_SOCKET, SO_TYPE,
226 				(char *)&_rpcfdtype, &ssize) == -1)
227 			exit(1);
228 		sock = 0;
229 		_rpcpmstart = 1;
230 		proto = 0;
231 		openlog("rpc.ypxfrd", LOG_PID, LOG_DAEMON);
232 	} else {
233 #ifndef RPC_SVC_FG
234 		int size;
235 		int pid, i;
236 
237 		pid = fork();
238 		if (pid < 0)
239 			err(1, "fork");
240 		if (pid)
241 			exit(0);
242 		size = getdtablesize();
243 		for (i = 0; i < size; i++)
244 			(void) close(i);
245 		i = open(_PATH_CONSOLE, 2);
246 		(void) dup2(i, 1);
247 		(void) dup2(i, 2);
248 		i = open(_PATH_TTY, 2);
249 		if (i >= 0) {
250 			(void) ioctl(i, TIOCNOTTY, (char *)NULL);
251 			(void) close(i);
252 		}
253 		openlog("rpc.ypxfrd", LOG_PID, LOG_DAEMON);
254 #endif
255 		sock = RPC_ANYSOCK;
256 		(void) pmap_unset(YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS);
257 	}
258 
259 	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
260 		transp = svcudp_create(sock);
261 		if (transp == NULL) {
262 			_msgout("cannot create udp service.");
263 			exit(1);
264 		}
265 		if (!_rpcpmstart)
266 			proto = IPPROTO_UDP;
267 		if (!svc_register(transp, YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, ypxfrd_freebsd_prog_1, proto)) {
268 			_msgout("unable to register (YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, udp).");
269 			exit(1);
270 		}
271 	}
272 
273 	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
274 		transp = svctcp_create(sock, 0, 0);
275 		if (transp == NULL) {
276 			_msgout("cannot create tcp service.");
277 			exit(1);
278 		}
279 		if (!_rpcpmstart)
280 			proto = IPPROTO_TCP;
281 		if (!svc_register(transp, YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, ypxfrd_freebsd_prog_1, proto)) {
282 			_msgout("unable to register (YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, tcp).");
283 			exit(1);
284 		}
285 	}
286 
287 	if (transp == (SVCXPRT *)NULL) {
288 		_msgout("could not create a handle");
289 		exit(1);
290 	}
291 	if (_rpcpmstart) {
292 		(void) signal(SIGALRM, (SIG_PF) closedown);
293 		(void) alarm(_RPCSVC_CLOSEDOWN/2);
294 	}
295 
296 	(void) signal(SIGPIPE, SIG_IGN);
297 	(void) signal(SIGCHLD, (SIG_PF) reaper);
298 	(void) signal(SIGTERM, (SIG_PF) reaper);
299 	(void) signal(SIGINT, (SIG_PF) reaper);
300 	(void) signal(SIGHUP, (SIG_PF) reaper);
301 
302 	ypxfrd_svc_run();
303 	_msgout("svc_run returned");
304 	exit(1);
305 	/* NOTREACHED */
306 }
307