1 /*
2  * Copyright (c) 1995, 1996
3  *	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
4  *
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.
19  *
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.
31  *
32  * $FreeBSD: src/usr.sbin/rpc.ypxfrd/ypxfrd_main.c,v 1.8.2.3 2002/02/15 00:46:58 des Exp $
33  */
34 
35 #include "ypxfrd.h"
36 #include <err.h>
37 #include <fcntl.h>
38 #include <paths.h>
39 #include <stdio.h>
40 #include <stdlib.h> /* getenv, exit */
41 #include <unistd.h>
42 #include <rpc/pmap_clnt.h> /* for pmap_unset */
43 #include <rpc/rpc_com.h>
44 #include <string.h> /* strcmp */
45 #include <signal.h>
46 #include <sys/ttycom.h> /* TIOCNOTTY */
47 #ifdef __cplusplus
48 #include <sysent.h> /* getdtablesize, open */
49 #endif /* __cplusplus */
50 #include <memory.h>
51 #include <sys/socket.h>
52 #include <netinet/in.h>
53 #include <syslog.h>
54 #include "ypxfrd_extern.h"
55 #include <sys/wait.h>
56 #include <errno.h>
57 
58 #ifndef SIG_PF
59 #define	SIG_PF void(*)(int)
60 #endif
61 
62 #ifdef DEBUG
63 #define	RPC_SVC_FG
64 #endif
65 
66 #define	_RPCSVC_CLOSEDOWN 120
67 int _rpcpmstart;		/* Started by a port monitor ? */
68 static int _rpcfdtype;
69 		 /* Whether Stream or Datagram ? */
70 	/* States a server can be in wrt request */
71 
72 #define	_IDLE 0
73 #define	_SERVED 1
74 #define	_SERVING 2
75 
76 extern int _rpcsvcstate;	 /* Set when a request is serviced */
77 
78 char *progname = "rpc.ypxfrd";
79 char *yp_dir = "/var/yp/";
80 
81 static void
82 _msgout(char *msg)
83 {
84 #ifdef RPC_SVC_FG
85 	if (_rpcpmstart)
86 		syslog(LOG_ERR, "%s", msg);
87 	else
88 		warnx("%s", msg);
89 #else
90 	syslog(LOG_ERR, "%s", msg);
91 #endif
92 }
93 
94 static void
95 closedown(int sig)
96 {
97 	if (_rpcsvcstate == _IDLE) {
98 		extern fd_set svc_fdset;
99 		static int size;
100 		int i, openfd;
101 
102 		if (_rpcfdtype == SOCK_DGRAM)
103 			exit(0);
104 		if (size == 0) {
105 			size = getdtablesize();
106 		}
107 		for (i = 0, openfd = 0; i < size && openfd < 2; i++)
108 			if (FD_ISSET(i, &svc_fdset))
109 				openfd++;
110 		if (openfd <= 1)
111 			exit(0);
112 	}
113 	if (_rpcsvcstate == _SERVED)
114 		_rpcsvcstate = _IDLE;
115 
116 	signal(SIGALRM, (SIG_PF) closedown);
117 	alarm(_RPCSVC_CLOSEDOWN/2);
118 }
119 
120 
121 static void
122 ypxfrd_svc_run(void)
123 {
124 #ifdef FD_SETSIZE
125 	fd_set readfds;
126 #else
127 	int readfds;
128 #endif /* def FD_SETSIZE */
129 	extern int forked;
130 	int pid;
131 	int fd_setsize = _rpc_dtablesize();
132 
133 	/* Establish the identity of the parent ypserv process. */
134 	pid = getpid();
135 
136 	for (;;) {
137 #ifdef FD_SETSIZE
138 		readfds = svc_fdset;
139 #else
140 		readfds = svc_fds;
141 #endif /* def FD_SETSIZE */
142 		switch (select(fd_setsize, &readfds, NULL, NULL, NULL)) {
143 		case -1:
144 			if (errno == EINTR) {
145 				continue;
146 			}
147 			warn("svc_run: - select failed");
148 			return;
149 		case 0:
150 			continue;
151 		default:
152 			svc_getreqset(&readfds);
153 			if (forked && pid != getpid())
154 				exit(0);
155 		}
156 	}
157 }
158 
159 static void
160 reaper(int sig)
161 {
162 	int			status;
163 	int			saved_errno;
164 
165 	saved_errno = errno;
166 
167 	if (sig == SIGHUP) {
168 		load_securenets();
169 		errno = saved_errno;
170 		return;
171 	}
172 
173 	if (sig == SIGCHLD) {
174 		while (wait3(&status, WNOHANG, NULL) > 0)
175 			children--;
176 	} else {
177 		pmap_unset(YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS);
178 		exit(0);
179 	}
180 
181 	errno = saved_errno;
182 	return;
183 }
184 
185 void
186 usage(void)
187 {
188 	fprintf(stderr, "usage: rpc.ypxfrd [-p path]\n");
189 	exit(0);
190 }
191 
192 int
193 main(int argc, char *argv[])
194 {
195 	SVCXPRT *transp = NULL;
196 	int sock;
197 	int proto = 0;
198 	struct sockaddr_in saddr;
199 	int asize = sizeof (saddr);
200 	int ch;
201 
202 	while ((ch = getopt(argc, argv, "p:h")) != -1) {
203 		switch (ch) {
204 		case 'p':
205 			yp_dir = optarg;
206 			break;
207 		default:
208 			usage();
209 			break;
210 		}
211 	}
212 
213 	load_securenets();
214 
215 	if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
216 		int ssize = sizeof (int);
217 
218 		if (saddr.sin_family != AF_INET)
219 			exit(1);
220 		if (getsockopt(0, SOL_SOCKET, SO_TYPE,
221 				(char *)&_rpcfdtype, &ssize) == -1)
222 			exit(1);
223 		sock = 0;
224 		_rpcpmstart = 1;
225 		proto = 0;
226 		openlog("rpc.ypxfrd", LOG_PID, LOG_DAEMON);
227 	} else {
228 #ifndef RPC_SVC_FG
229 		int size;
230 		int pid, i;
231 
232 		pid = fork();
233 		if (pid < 0)
234 			err(1, "fork");
235 		if (pid)
236 			exit(0);
237 		size = getdtablesize();
238 		for (i = 0; i < size; i++)
239 			close(i);
240 		i = open(_PATH_CONSOLE, 2);
241 		dup2(i, 1);
242 		dup2(i, 2);
243 		i = open(_PATH_TTY, 2);
244 		if (i >= 0) {
245 			ioctl(i, TIOCNOTTY, NULL);
246 			close(i);
247 		}
248 		openlog("rpc.ypxfrd", LOG_PID, LOG_DAEMON);
249 #endif
250 		sock = RPC_ANYSOCK;
251 		pmap_unset(YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS);
252 	}
253 
254 	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
255 		transp = svcudp_create(sock);
256 		if (transp == NULL) {
257 			_msgout("cannot create udp service.");
258 			exit(1);
259 		}
260 		if (!_rpcpmstart)
261 			proto = IPPROTO_UDP;
262 		if (!svc_register(transp, YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, ypxfrd_freebsd_prog_1, proto)) {
263 			_msgout("unable to register (YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, udp).");
264 			exit(1);
265 		}
266 	}
267 
268 	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
269 		transp = svctcp_create(sock, 0, 0);
270 		if (transp == NULL) {
271 			_msgout("cannot create tcp service.");
272 			exit(1);
273 		}
274 		if (!_rpcpmstart)
275 			proto = IPPROTO_TCP;
276 		if (!svc_register(transp, YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, ypxfrd_freebsd_prog_1, proto)) {
277 			_msgout("unable to register (YPXFRD_FREEBSD_PROG, YPXFRD_FREEBSD_VERS, tcp).");
278 			exit(1);
279 		}
280 	}
281 
282 	if (transp == NULL) {
283 		_msgout("could not create a handle");
284 		exit(1);
285 	}
286 	if (_rpcpmstart) {
287 		signal(SIGALRM, (SIG_PF) closedown);
288 		alarm(_RPCSVC_CLOSEDOWN/2);
289 	}
290 
291 	signal(SIGPIPE, SIG_IGN);
292 	signal(SIGCHLD, (SIG_PF) reaper);
293 	signal(SIGTERM, (SIG_PF) reaper);
294 	signal(SIGINT, (SIG_PF) reaper);
295 	signal(SIGHUP, (SIG_PF) reaper);
296 
297 	ypxfrd_svc_run();
298 	_msgout("svc_run returned");
299 	exit(1);
300 	/* NOTREACHED */
301 }
302