yp_main.c revision 175951 
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 175951 2008-02-03 17:39:37Z matteo $");
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
87struct socktype {
88	const char *st_name;
89	int	   st_type;
90};
91static struct socktype stlist[] = {
92	{ "tcp", SOCK_STREAM },
93	{ "udp", SOCK_DGRAM },
94	{ NULL, 0 }
95};
96
97static
98void _msgout(char* msg)
99{
100	if (debug) {
101		if (_rpcpmstart)
102			syslog(LOG_ERR, "%s", msg);
103		else
104			warnx("%s", msg);
105	} else
106		syslog(LOG_ERR, "%s", msg);
107}
108
109pid_t	yp_pid;
110
111static void
112yp_svc_run(void)
113{
114#ifdef FD_SETSIZE
115	fd_set readfds;
116#else
117	int readfds;
118#endif /* def FD_SETSIZE */
119	int fd_setsize = _rpc_dtablesize();
120	struct timeval timeout;
121
122	/* Establish the identity of the parent ypserv process. */
123	yp_pid = getpid();
124
125	for (;;) {
126#ifdef FD_SETSIZE
127		readfds = svc_fdset;
128#else
129		readfds = svc_fds;
130#endif /* def FD_SETSIZE */
131
132		FD_SET(resfd, &readfds);
133
134		timeout.tv_sec = RESOLVER_TIMEOUT;
135		timeout.tv_usec = 0;
136		switch (select(fd_setsize, &readfds, NULL, NULL,
137			       &timeout)) {
138		case -1:
139			if (errno == EINTR) {
140				continue;
141			}
142			warn("svc_run: - select failed");
143			return;
144		case 0:
145			if (getpid() == yp_pid)
146				yp_prune_dnsq();
147			break;
148		default:
149			if (getpid() == yp_pid) {
150				if (FD_ISSET(resfd, &readfds)) {
151					yp_run_dnsq();
152					FD_CLR(resfd, &readfds);
153				}
154				svc_getreqset(&readfds);
155			}
156		}
157		if (yp_pid != getpid())
158			_exit(0);
159	}
160}
161
162static void
163unregister(void)
164{
165	(void) pmap_unset(YPPROG, YPVERS);
166	(void) pmap_unset(YPPROG, YPOLDVERS);
167}
168
169static void
170reaper(int sig)
171{
172	int			status;
173	int			saved_errno;
174
175	saved_errno = errno;
176
177	if (sig == SIGHUP) {
178		load_securenets();
179#ifdef DB_CACHE
180		yp_flush_all();
181#endif
182		errno = saved_errno;
183		return;
184	}
185
186	if (sig == SIGCHLD) {
187		while (wait3(&status, WNOHANG, NULL) > 0)
188			children--;
189	} else {
190		unregister();
191		exit(0);
192	}
193	errno = saved_errno;
194	return;
195}
196
197static void
198usage(void)
199{
200	fprintf(stderr, "usage: ypserv [-h] [-d] [-n] [-p path] [-P port]\n");
201	exit(1);
202}
203
204static void
205closedown(int sig)
206{
207	if (_rpcsvcstate == _IDLE) {
208		extern fd_set svc_fdset;
209		static int size;
210		int i, openfd;
211
212		if (_rpcfdtype == SOCK_DGRAM) {
213			unregister();
214			exit(0);
215		}
216		if (size == 0) {
217			size = getdtablesize();
218		}
219		for (i = 0, openfd = 0; i < size && openfd < 2; i++)
220			if (FD_ISSET(i, &svc_fdset))
221				openfd++;
222		if (openfd <= 1) {
223			unregister();
224			exit(0);
225		}
226	}
227	if (_rpcsvcstate == _SERVED)
228		_rpcsvcstate = _IDLE;
229
230	(void) signal(SIGALRM, (SIG_PF) closedown);
231	(void) alarm(_RPCSVC_CLOSEDOWN/2);
232}
233
234int
235main(int argc, char *argv[])
236{
237	register SVCXPRT *transp = NULL;
238	int sock;
239	int proto = 0;
240	struct sockaddr_in saddr;
241	socklen_t asize = sizeof (saddr);
242	int ch;
243	in_port_t yp_port = 0;
244	char *errstr;
245	struct socktype *st;
246
247	while ((ch = getopt(argc, argv, "hdnp:P:")) != -1) {
248		switch (ch) {
249		case 'd':
250			debug = ypdb_debug = 1;
251			break;
252		case 'n':
253			do_dns = 1;
254			break;
255		case 'p':
256			yp_dir = optarg;
257			break;
258		case 'P':
259			yp_port = (in_port_t)strtonum(optarg, 1, 65535,
260			    (const char **)&errstr);
261			if (yp_port == 0 && errstr != NULL) {
262				_msgout("invalid port number provided");
263				exit(1);
264			}
265			break;
266		case 'h':
267		default:
268			usage();
269		}
270	}
271
272	load_securenets();
273	yp_init_resolver();
274#ifdef DB_CACHE
275	yp_init_dbs();
276#endif
277	if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
278		int ssize = sizeof (int);
279
280		if (saddr.sin_family != AF_INET)
281			exit(1);
282		if (getsockopt(0, SOL_SOCKET, SO_TYPE,
283				(char *)&_rpcfdtype, &ssize) == -1)
284			exit(1);
285		sock = 0;
286		_rpcpmstart = 1;
287		proto = 0;
288		openlog("ypserv", LOG_PID, LOG_DAEMON);
289	} else {
290		if (!debug) {
291			if (daemon(0,0)) {
292				err(1,"cannot fork");
293			}
294			openlog("ypserv", LOG_PID, LOG_DAEMON);
295		}
296		sock = RPC_ANYSOCK;
297		(void) pmap_unset(YPPROG, YPVERS);
298		(void) pmap_unset(YPPROG, 1);
299	}
300
301	/*
302	 * Initialize TCP/UDP sockets.
303	 */
304	memset((char *)&saddr, 0, sizeof(saddr));
305	saddr.sin_family = AF_INET;
306	saddr.sin_addr.s_addr = htonl(INADDR_ANY);
307	saddr.sin_port = htons(yp_port);
308	for (st = stlist; st->st_name != NULL; st++) {
309		/* Do not bind the socket if the user didn't specify a port */
310		if (yp_port == 0)
311			break;
312
313		sock = socket(AF_INET, st->st_type, 0);
314		if (sock == -1) {
315			if ((asprintf(&errstr, "cannot create a %s socket",
316			    st->st_name)) == -1)
317				err(1, "unexpected failure in asprintf()");
318			_msgout(errstr);
319			free((void *)errstr);
320			exit(1);
321		}
322		if (bind(sock, (struct sockaddr *) &saddr, sizeof(saddr))
323		    == -1) {
324			if ((asprintf(&errstr, "cannot bind %s socket",
325			    st->st_name)) == -1)
326				err(1, "unexpected failure in asprintf()");
327			_msgout(errstr);
328			free((void *)errstr);
329			exit(1);
330		}
331		errstr = NULL;
332	}
333
334	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
335		transp = svcudp_create(sock);
336		if (transp == NULL) {
337			_msgout("cannot create udp service");
338			exit(1);
339		}
340		if (!_rpcpmstart)
341			proto = IPPROTO_UDP;
342		if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
343			_msgout("unable to register (YPPROG, YPOLDVERS, udp)");
344			exit(1);
345		}
346		if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
347			_msgout("unable to register (YPPROG, YPVERS, udp)");
348			exit(1);
349		}
350	}
351
352	if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
353		transp = svctcp_create(sock, 0, 0);
354		if (transp == NULL) {
355			_msgout("cannot create tcp service");
356			exit(1);
357		}
358		if (!_rpcpmstart)
359			proto = IPPROTO_TCP;
360		if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
361			_msgout("unable to register (YPPROG, YPOLDVERS, tcp)");
362			exit(1);
363		}
364		if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
365			_msgout("unable to register (YPPROG, YPVERS, tcp)");
366			exit(1);
367		}
368	}
369
370	if (transp == (SVCXPRT *)NULL) {
371		_msgout("could not create a handle");
372		exit(1);
373	}
374	if (_rpcpmstart) {
375		(void) signal(SIGALRM, (SIG_PF) closedown);
376		(void) alarm(_RPCSVC_CLOSEDOWN/2);
377	}
378/*
379 * Make sure SIGPIPE doesn't blow us away while servicing TCP
380 * connections.
381 */
382	(void) signal(SIGPIPE, SIG_IGN);
383	(void) signal(SIGCHLD, (SIG_PF) reaper);
384	(void) signal(SIGTERM, (SIG_PF) reaper);
385	(void) signal(SIGINT, (SIG_PF) reaper);
386	(void) signal(SIGHUP, (SIG_PF) reaper);
387	yp_svc_run();
388	_msgout("svc_run returned");
389	exit(1);
390	/* NOTREACHED */
391}
392