yp_main.c revision 90298 
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#ifndef lint
34static const char rcsid[] =
35  "$FreeBSD: head/usr.sbin/ypserv/yp_main.c 90298 2002-02-06 15:26:07Z des $";
36#endif /* not lint */
37
38/*
39 * ypserv startup function.
40 * We need out own main() since we have to do some additional work
41 * that rpcgen won't do for us. Most of this file was generated using
42 * rpcgen.new, and later modified.
43 */
44
45#include "yp.h"
46#include <err.h>
47#include <errno.h>
48#include <memory.h>
49#include <stdio.h>
50#include <signal.h>
51#include <stdlib.h> /* getenv, exit */
52#include <string.h> /* strcmp */
53#include <syslog.h>
54#include <unistd.h>
55#include <rpc/pmap_clnt.h> /* for pmap_unset */
56#ifdef __cplusplus
57#include <sysent.h> /* getdtablesize, open */
58#endif /* __cplusplus */
59#include <sys/socket.h>
60#include <netinet/in.h>
61#include <sys/wait.h>
62#include "yp_extern.h"
63#include <rpc/rpc.h>
64
65#ifndef SIG_PF
66#define	SIG_PF void(*)(int)
67#endif
68
69#define	_RPCSVC_CLOSEDOWN 120
70int _rpcpmstart;		/* Started by a port monitor ? */
71static 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
79extern void ypprog_1(struct svc_req *, register SVCXPRT *);
80extern void ypprog_2(struct svc_req *, register SVCXPRT *);
81extern int _rpc_dtablesize(void);
82extern int _rpcsvcstate;	 /* Set when a request is serviced */
83char *progname = "ypserv";
84char *yp_dir = _PATH_YP;
85/*int debug = 0;*/
86int do_dns = 0;
87int resfd;
88
89static
90void _msgout(char* msg)
91{
92	if (debug) {
93		if (_rpcpmstart)
94			syslog(LOG_ERR, "%s", msg);
95		else
96			warnx("%s", msg);
97	} else
98		syslog(LOG_ERR, "%s", msg);
99}
100
101pid_t	yp_pid;
102
103static void
104yp_svc_run(void)
105{
106#ifdef FD_SETSIZE
107	fd_set readfds;
108#else
109	int readfds;
110#endif /* def FD_SETSIZE */
111	extern int forked;
112	int fd_setsize = _rpc_dtablesize();
113	struct timeval timeout;
114
115	/* Establish the identity of the parent ypserv process. */
116	yp_pid = getpid();
117
118	for (;;) {
119#ifdef FD_SETSIZE
120		readfds = svc_fdset;
121#else
122		readfds = svc_fds;
123#endif /* def FD_SETSIZE */
124
125		FD_SET(resfd, &readfds);
126
127		timeout.tv_sec = RESOLVER_TIMEOUT;
128		timeout.tv_usec = 0;
129		switch (select(fd_setsize, &readfds, NULL, NULL,
130			       &timeout)) {
131		case -1:
132			if (errno == EINTR) {
133				continue;
134			}
135			warn("svc_run: - select failed");
136			return;
137		case 0:
138			if (getpid() == yp_pid)
139				yp_prune_dnsq();
140			break;
141		default:
142			if (getpid() == yp_pid) {
143				if (FD_ISSET(resfd, &readfds)) {
144					yp_run_dnsq();
145					FD_CLR(resfd, &readfds);
146				}
147				svc_getreqset(&readfds);
148			}
149		}
150		if (yp_pid != getpid())
151			_exit(0);
152	}
153}
154
155static void
156unregister(void)
157{
158	(void) pmap_unset(YPPROG, YPVERS);
159	(void) pmap_unset(YPPROG, YPOLDVERS);
160}
161
162static void
163reaper(int sig)
164{
165	int			status;
166	int			saved_errno;
167
168	saved_errno = errno;
169
170	if (sig == SIGHUP) {
171		load_securenets();
172#ifdef DB_CACHE
173		yp_flush_all();
174#endif
175		errno = saved_errno;
176		return;
177	}
178
179	if (sig == SIGCHLD) {
180		while (wait3(&status, WNOHANG, NULL) > 0)
181			children--;
182	} else {
183		unregister();
184		exit(0);
185	}
186	errno = saved_errno;
187	return;
188}
189
190static void
191usage(void)
192{
193	fprintf(stderr, "usage: ypserv [-h] [-d] [-n] [-p path]\n");
194	exit(1);
195}
196
197static void
198closedown(int sig)
199{
200	if (_rpcsvcstate == _IDLE) {
201		extern fd_set svc_fdset;
202		static int size;
203		int i, openfd;
204
205		if (_rpcfdtype == SOCK_DGRAM) {
206			unregister();
207			exit(0);
208		}
209		if (size == 0) {
210			size = getdtablesize();
211		}
212		for (i = 0, openfd = 0; i < size && openfd < 2; i++)
213			if (FD_ISSET(i, &svc_fdset))
214				openfd++;
215		if (openfd <= 1) {
216			unregister();
217			exit(0);
218		}
219	}
220	if (_rpcsvcstate == _SERVED)
221		_rpcsvcstate = _IDLE;
222
223	(void) signal(SIGALRM, (SIG_PF) closedown);
224	(void) alarm(_RPCSVC_CLOSEDOWN/2);
225}
226
227int
228main(int argc, char *argv[])
229{
230	register SVCXPRT *transp = NULL;
231	int sock;
232	int proto = 0;
233	struct sockaddr_in saddr;
234	int asize = sizeof (saddr);
235	int ch;
236
237	while ((ch = getopt(argc, argv, "hdnp:")) != -1) {
238		switch (ch) {
239		case 'd':
240			debug = ypdb_debug = 1;
241			break;
242		case 'n':
243			do_dns = 1;
244			break;
245		case 'p':
246			yp_dir = optarg;
247			break;
248		case 'h':
249		default:
250			usage();
251		}
252	}
253
254	load_securenets();
255	yp_init_resolver();
256#ifdef DB_CACHE
257	yp_init_dbs();
258#endif
259	if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
260		int ssize = sizeof (int);
261
262		if (saddr.sin_family != AF_INET)
263			exit(1);
264		if (getsockopt(0, SOL_SOCKET, SO_TYPE,
265				(char *)&_rpcfdtype, &ssize) == -1)
266			exit(1);
267		sock = 0;
268		_rpcpmstart = 1;
269		proto = 0;
270		openlog("ypserv", LOG_PID, LOG_DAEMON);
271	} else {
272		if (!debug) {
273			if (daemon(0,0)) {
274				err(1,"cannot fork");
275			}
276			openlog("ypserv", LOG_PID, LOG_DAEMON);
277		}
278		sock = RPC_ANYSOCK;
279		(void) pmap_unset(YPPROG, YPVERS);
280		(void) pmap_unset(YPPROG, 1);
281	}
282
283	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
284		transp = svcudp_create(sock);
285		if (transp == NULL) {
286			_msgout("cannot create udp service");
287			exit(1);
288		}
289		if (!_rpcpmstart)
290			proto = IPPROTO_UDP;
291		if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
292			_msgout("unable to register (YPPROG, YPOLDVERS, udp)");
293			exit(1);
294		}
295		if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
296			_msgout("unable to register (YPPROG, YPVERS, udp)");
297			exit(1);
298		}
299	}
300
301	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
302		transp = svctcp_create(sock, 0, 0);
303		if (transp == NULL) {
304			_msgout("cannot create tcp service");
305			exit(1);
306		}
307		if (!_rpcpmstart)
308			proto = IPPROTO_TCP;
309		if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
310			_msgout("unable to register (YPPROG, YPOLDVERS, tcp)");
311			exit(1);
312		}
313		if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
314			_msgout("unable to register (YPPROG, YPVERS, tcp)");
315			exit(1);
316		}
317	}
318
319	if (transp == (SVCXPRT *)NULL) {
320		_msgout("could not create a handle");
321		exit(1);
322	}
323	if (_rpcpmstart) {
324		(void) signal(SIGALRM, (SIG_PF) closedown);
325		(void) alarm(_RPCSVC_CLOSEDOWN/2);
326	}
327/*
328 * Make sure SIGPIPE doesn't blow us away while servicing TCP
329 * connections.
330 */
331	(void) signal(SIGPIPE, SIG_IGN);
332	(void) signal(SIGCHLD, (SIG_PF) reaper);
333	(void) signal(SIGTERM, (SIG_PF) reaper);
334	(void) signal(SIGINT, (SIG_PF) reaper);
335	(void) signal(SIGHUP, (SIG_PF) reaper);
336	yp_svc_run();
337	_msgout("svc_run returned");
338	exit(1);
339	/* NOTREACHED */
340}
341