yp_main.c revision 114601
1/*
2 * Copyright (c) 1995
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
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: head/usr.sbin/ypserv/yp_main.c 114601 2003-05-03 21:06:42Z obrien $");
35
36/*
37 * ypserv startup function.
38 * We need out own main() since we have to do some additional work
39 * that rpcgen won't do for us. Most of this file was generated using
40 * rpcgen.new, and later modified.
41 */
42
43#include "yp.h"
44#include <err.h>
45#include <errno.h>
46#include <memory.h>
47#include <stdio.h>
48#include <signal.h>
49#include <stdlib.h> /* getenv, exit */
50#include <string.h> /* strcmp */
51#include <syslog.h>
52#include <unistd.h>
53#include <rpc/pmap_clnt.h> /* for pmap_unset */
54#ifdef __cplusplus
55#include <sysent.h> /* getdtablesize, open */
56#endif /* __cplusplus */
57#include <sys/socket.h>
58#include <netinet/in.h>
59#include <sys/wait.h>
60#include "yp_extern.h"
61#include <rpc/rpc.h>
62
63#ifndef SIG_PF
64#define	SIG_PF void(*)(int)
65#endif
66
67#define	_RPCSVC_CLOSEDOWN 120
68int _rpcpmstart;		/* Started by a port monitor ? */
69static int _rpcfdtype;
70		 /* Whether Stream or Datagram ? */
71	/* States a server can be in wrt request */
72
73#define	_IDLE 0
74#define	_SERVED 1
75#define	_SERVING 2
76
77extern void ypprog_1(struct svc_req *, register SVCXPRT *);
78extern void ypprog_2(struct svc_req *, register SVCXPRT *);
79extern int _rpc_dtablesize(void);
80extern int _rpcsvcstate;	 /* Set when a request is serviced */
81char *progname = "ypserv";
82char *yp_dir = _PATH_YP;
83/*int debug = 0;*/
84int do_dns = 0;
85int resfd;
86
87static
88void _msgout(char* msg)
89{
90	if (debug) {
91		if (_rpcpmstart)
92			syslog(LOG_ERR, "%s", msg);
93		else
94			warnx("%s", msg);
95	} else
96		syslog(LOG_ERR, "%s", msg);
97}
98
99pid_t	yp_pid;
100
101static void
102yp_svc_run(void)
103{
104#ifdef FD_SETSIZE
105	fd_set readfds;
106#else
107	int readfds;
108#endif /* def FD_SETSIZE */
109	extern int forked;
110	int fd_setsize = _rpc_dtablesize();
111	struct timeval timeout;
112
113	/* Establish the identity of the parent ypserv process. */
114	yp_pid = getpid();
115
116	for (;;) {
117#ifdef FD_SETSIZE
118		readfds = svc_fdset;
119#else
120		readfds = svc_fds;
121#endif /* def FD_SETSIZE */
122
123		FD_SET(resfd, &readfds);
124
125		timeout.tv_sec = RESOLVER_TIMEOUT;
126		timeout.tv_usec = 0;
127		switch (select(fd_setsize, &readfds, NULL, NULL,
128			       &timeout)) {
129		case -1:
130			if (errno == EINTR) {
131				continue;
132			}
133			warn("svc_run: - select failed");
134			return;
135		case 0:
136			if (getpid() == yp_pid)
137				yp_prune_dnsq();
138			break;
139		default:
140			if (getpid() == yp_pid) {
141				if (FD_ISSET(resfd, &readfds)) {
142					yp_run_dnsq();
143					FD_CLR(resfd, &readfds);
144				}
145				svc_getreqset(&readfds);
146			}
147		}
148		if (yp_pid != getpid())
149			_exit(0);
150	}
151}
152
153static void
154unregister(void)
155{
156	(void) pmap_unset(YPPROG, YPVERS);
157	(void) pmap_unset(YPPROG, YPOLDVERS);
158}
159
160static void
161reaper(int sig)
162{
163	int			status;
164	int			saved_errno;
165
166	saved_errno = errno;
167
168	if (sig == SIGHUP) {
169		load_securenets();
170#ifdef DB_CACHE
171		yp_flush_all();
172#endif
173		errno = saved_errno;
174		return;
175	}
176
177	if (sig == SIGCHLD) {
178		while (wait3(&status, WNOHANG, NULL) > 0)
179			children--;
180	} else {
181		unregister();
182		exit(0);
183	}
184	errno = saved_errno;
185	return;
186}
187
188static void
189usage(void)
190{
191	fprintf(stderr, "usage: ypserv [-h] [-d] [-n] [-p path]\n");
192	exit(1);
193}
194
195static void
196closedown(int sig)
197{
198	if (_rpcsvcstate == _IDLE) {
199		extern fd_set svc_fdset;
200		static int size;
201		int i, openfd;
202
203		if (_rpcfdtype == SOCK_DGRAM) {
204			unregister();
205			exit(0);
206		}
207		if (size == 0) {
208			size = getdtablesize();
209		}
210		for (i = 0, openfd = 0; i < size && openfd < 2; i++)
211			if (FD_ISSET(i, &svc_fdset))
212				openfd++;
213		if (openfd <= 1) {
214			unregister();
215			exit(0);
216		}
217	}
218	if (_rpcsvcstate == _SERVED)
219		_rpcsvcstate = _IDLE;
220
221	(void) signal(SIGALRM, (SIG_PF) closedown);
222	(void) alarm(_RPCSVC_CLOSEDOWN/2);
223}
224
225int
226main(int argc, char *argv[])
227{
228	register SVCXPRT *transp = NULL;
229	int sock;
230	int proto = 0;
231	struct sockaddr_in saddr;
232	int asize = sizeof (saddr);
233	int ch;
234
235	while ((ch = getopt(argc, argv, "hdnp:")) != -1) {
236		switch (ch) {
237		case 'd':
238			debug = ypdb_debug = 1;
239			break;
240		case 'n':
241			do_dns = 1;
242			break;
243		case 'p':
244			yp_dir = optarg;
245			break;
246		case 'h':
247		default:
248			usage();
249		}
250	}
251
252	load_securenets();
253	yp_init_resolver();
254#ifdef DB_CACHE
255	yp_init_dbs();
256#endif
257	if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
258		int ssize = sizeof (int);
259
260		if (saddr.sin_family != AF_INET)
261			exit(1);
262		if (getsockopt(0, SOL_SOCKET, SO_TYPE,
263				(char *)&_rpcfdtype, &ssize) == -1)
264			exit(1);
265		sock = 0;
266		_rpcpmstart = 1;
267		proto = 0;
268		openlog("ypserv", LOG_PID, LOG_DAEMON);
269	} else {
270		if (!debug) {
271			if (daemon(0,0)) {
272				err(1,"cannot fork");
273			}
274			openlog("ypserv", LOG_PID, LOG_DAEMON);
275		}
276		sock = RPC_ANYSOCK;
277		(void) pmap_unset(YPPROG, YPVERS);
278		(void) pmap_unset(YPPROG, 1);
279	}
280
281	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
282		transp = svcudp_create(sock);
283		if (transp == NULL) {
284			_msgout("cannot create udp service");
285			exit(1);
286		}
287		if (!_rpcpmstart)
288			proto = IPPROTO_UDP;
289		if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
290			_msgout("unable to register (YPPROG, YPOLDVERS, udp)");
291			exit(1);
292		}
293		if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
294			_msgout("unable to register (YPPROG, YPVERS, udp)");
295			exit(1);
296		}
297	}
298
299	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
300		transp = svctcp_create(sock, 0, 0);
301		if (transp == NULL) {
302			_msgout("cannot create tcp service");
303			exit(1);
304		}
305		if (!_rpcpmstart)
306			proto = IPPROTO_TCP;
307		if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
308			_msgout("unable to register (YPPROG, YPOLDVERS, tcp)");
309			exit(1);
310		}
311		if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
312			_msgout("unable to register (YPPROG, YPVERS, tcp)");
313			exit(1);
314		}
315	}
316
317	if (transp == (SVCXPRT *)NULL) {
318		_msgout("could not create a handle");
319		exit(1);
320	}
321	if (_rpcpmstart) {
322		(void) signal(SIGALRM, (SIG_PF) closedown);
323		(void) alarm(_RPCSVC_CLOSEDOWN/2);
324	}
325/*
326 * Make sure SIGPIPE doesn't blow us away while servicing TCP
327 * connections.
328 */
329	(void) signal(SIGPIPE, SIG_IGN);
330	(void) signal(SIGCHLD, (SIG_PF) reaper);
331	(void) signal(SIGTERM, (SIG_PF) reaper);
332	(void) signal(SIGINT, (SIG_PF) reaper);
333	(void) signal(SIGHUP, (SIG_PF) reaper);
334	yp_svc_run();
335	_msgout("svc_run returned");
336	exit(1);
337	/* NOTREACHED */
338}
339