xref: /openbsd/sbin/nfsd/nfsd.c (revision cca36db2)
1 /*	$OpenBSD: nfsd.c,v 1.31 2010/04/17 16:27:49 krw Exp $	*/
2 /*	$NetBSD: nfsd.c,v 1.19 1996/02/18 23:18:56 mycroft Exp $	*/
3 
4 /*
5  * Copyright (c) 1989, 1993, 1994
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Rick Macklem at The University of Guelph.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/param.h>
37 #include <sys/ioctl.h>
38 #include <sys/stat.h>
39 #include <sys/wait.h>
40 #include <sys/uio.h>
41 #include <sys/ucred.h>
42 #include <sys/mount.h>
43 #include <sys/socket.h>
44 #include <sys/socketvar.h>
45 
46 #include <rpc/rpc.h>
47 #include <rpc/pmap_clnt.h>
48 #include <rpc/pmap_prot.h>
49 
50 #include <nfs/rpcv2.h>
51 #include <nfs/nfsproto.h>
52 #include <nfs/nfs.h>
53 
54 #include <err.h>
55 #include <errno.h>
56 #include <fcntl.h>
57 #include <grp.h>
58 #include <pwd.h>
59 #include <signal.h>
60 #include <stdio.h>
61 #include <stdlib.h>
62 #include <string.h>
63 #include <syslog.h>
64 #include <unistd.h>
65 
66 /* Global defs */
67 #ifdef DEBUG
68 #define	syslog(e, s)	fprintf(stderr,(s))
69 int	debug = 1;
70 #else
71 int	debug = 0;
72 #endif
73 
74 struct	nfsd_srvargs nsd;
75 
76 void	nonfs(int);
77 void	reapchild(int);
78 void	usage(void);
79 
80 #define	MAXNFSDCNT	20
81 #define	DEFNFSDCNT	 4
82 
83 /*
84  * Nfs server daemon mostly just a user context for nfssvc()
85  *
86  * 1 - do file descriptor and signal cleanup
87  * 2 - fork the nfsd(s)
88  * 3 - create server socket(s)
89  * 4 - register socket with portmap
90  *
91  * For connectionless protocols, just pass the socket into the kernel via.
92  * nfssvc().
93  * For connection based sockets, loop doing accepts. When you get a new
94  * socket from accept, pass the msgsock into the kernel via. nfssvc().
95  * The arguments are:
96  *	-r - reregister with portmapper
97  *	-t - support tcp nfs clients
98  *	-u - support udp nfs clients
99  * followed by "n" which is the number of nfsds' to fork off
100  */
101 int
102 main(int argc, char *argv[])
103 {
104 	struct nfsd_args nfsdargs;
105 	struct sockaddr_in inetaddr, inetpeer;
106 	fd_set *ready, *sockbits;
107 	size_t fd_size;
108 	int ch, connect_type_cnt, i, maxsock = 0, msgsock;
109 	int nfsdcnt = DEFNFSDCNT, on, reregister = 0, sock;
110 	int udpflag = 0, tcpflag = 0, tcpsock;
111 	const char *errstr = NULL;
112 	socklen_t len;
113 
114 	/* Start by writing to both console and log. */
115 	openlog("nfsd", LOG_PID | LOG_PERROR, LOG_DAEMON);
116 
117 	if (argc == 1)
118 		udpflag = 1;
119 	while ((ch = getopt(argc, argv, "n:rtu")) != -1)
120 		switch (ch) {
121 		case 'n':
122 			nfsdcnt = strtonum(optarg, 1, MAXNFSDCNT, &errstr);
123 			if (errstr) {
124 				syslog(LOG_ERR, "nfsd count is %s: %s", errstr, optarg);
125 				return(1);
126 			}
127 			break;
128 		case 'r':
129 			reregister = 1;
130 			break;
131 		case 't':
132 			tcpflag = 1;
133 			break;
134 		case 'u':
135 			udpflag = 1;
136 			break;
137 		default:
138 			usage();
139 		};
140 	argv += optind;
141 	argc -= optind;
142 
143 	/*
144 	 * XXX
145 	 * Backward compatibility, trailing number is the count of daemons.
146 	 */
147 	if (argc > 1)
148 		usage();
149 	if (argc == 1) {
150 		nfsdcnt = strtonum(argv[0], 1, MAXNFSDCNT, &errstr);
151 		if (errstr) {
152 			syslog(LOG_ERR, "nfsd count is %s: %s", errstr, optarg);
153 			return(1);
154 		}
155 	}
156 
157 	if (debug == 0) {
158 		daemon(0, 0);
159 		(void)signal(SIGHUP, SIG_IGN);
160 		(void)signal(SIGINT, SIG_IGN);
161 		(void)signal(SIGQUIT, SIG_IGN);
162 		(void)signal(SIGSYS, nonfs);
163 	}
164 	(void)signal(SIGCHLD, reapchild);
165 
166 	if (reregister) {
167 		if (udpflag &&
168 		    (!pmap_set(RPCPROG_NFS, 2, IPPROTO_UDP, NFS_PORT) ||
169 		     !pmap_set(RPCPROG_NFS, 3, IPPROTO_UDP, NFS_PORT))) {
170 			syslog(LOG_ERR, "can't register with portmap for UDP (%m).");
171 			return (1);
172 		}
173 		if (tcpflag &&
174 		    (!pmap_set(RPCPROG_NFS, 2, IPPROTO_TCP, NFS_PORT) ||
175 		     !pmap_set(RPCPROG_NFS, 3, IPPROTO_TCP, NFS_PORT))) {
176 			syslog(LOG_ERR, "can't register with portmap for TCP (%m).");
177 			return (1);
178 		}
179 		return (0);
180 	}
181 
182 	/* Cut back to writing to log only. */
183 	closelog();
184 	openlog("nfsd", LOG_PID, LOG_DAEMON);
185 
186 	for (i = 0; i < nfsdcnt; i++) {
187 		switch (fork()) {
188 		case -1:
189 			syslog(LOG_ERR, "fork: %m");
190 			return (1);
191 		case 0:
192 			break;
193 		default:
194 			continue;
195 		}
196 
197 		setproctitle("server");
198 		nsd.nsd_nfsd = NULL;
199 		if (nfssvc(NFSSVC_NFSD, &nsd) < 0) {
200 			syslog(LOG_ERR, "nfssvc: %m");
201 			return (1);
202 		}
203 		return (0);
204 	}
205 
206 	/* If we are serving udp, set up the socket. */
207 	if (udpflag) {
208 		if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
209 			syslog(LOG_ERR, "can't create udp socket");
210 			return (1);
211 		}
212 		memset(&inetaddr, 0, sizeof inetaddr);
213 		inetaddr.sin_family = AF_INET;
214 		inetaddr.sin_addr.s_addr = INADDR_ANY;
215 		inetaddr.sin_port = htons(NFS_PORT);
216 		inetaddr.sin_len = sizeof(inetaddr);
217 		if (bind(sock, (struct sockaddr *)&inetaddr,
218 		    sizeof(inetaddr)) < 0) {
219 			syslog(LOG_ERR, "can't bind udp addr");
220 			return (1);
221 		}
222 		if (!pmap_set(RPCPROG_NFS, 2, IPPROTO_UDP, NFS_PORT) ||
223 		    !pmap_set(RPCPROG_NFS, 3, IPPROTO_UDP, NFS_PORT)) {
224 			syslog(LOG_ERR, "can't register with udp portmap");
225 			return (1);
226 		}
227 		nfsdargs.sock = sock;
228 		nfsdargs.name = NULL;
229 		nfsdargs.namelen = 0;
230 		if (nfssvc(NFSSVC_ADDSOCK, &nfsdargs) < 0) {
231 			syslog(LOG_ERR, "can't Add UDP socket");
232 			return (1);
233 		}
234 		(void)close(sock);
235 	}
236 
237 	/* Now set up the master server socket waiting for tcp connections. */
238 	on = 1;
239 	connect_type_cnt = 0;
240 	if (tcpflag) {
241 		if ((tcpsock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
242 			syslog(LOG_ERR, "can't create tcp socket");
243 			return (1);
244 		}
245 		if (setsockopt(tcpsock,
246 		    SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
247 			syslog(LOG_ERR, "setsockopt SO_REUSEADDR: %m");
248 		memset(&inetaddr, 0, sizeof inetaddr);
249 		inetaddr.sin_family = AF_INET;
250 		inetaddr.sin_addr.s_addr = INADDR_ANY;
251 		inetaddr.sin_port = htons(NFS_PORT);
252 		inetaddr.sin_len = sizeof(inetaddr);
253 		if (bind(tcpsock, (struct sockaddr *)&inetaddr,
254 		    sizeof (inetaddr)) < 0) {
255 			syslog(LOG_ERR, "can't bind tcp addr");
256 			return (1);
257 		}
258 		if (listen(tcpsock, 5) < 0) {
259 			syslog(LOG_ERR, "listen failed");
260 			return (1);
261 		}
262 		if (!pmap_set(RPCPROG_NFS, 2, IPPROTO_TCP, NFS_PORT) ||
263 		    !pmap_set(RPCPROG_NFS, 3, IPPROTO_TCP, NFS_PORT)) {
264 			syslog(LOG_ERR, "can't register tcp with portmap");
265 			return (1);
266 		}
267 		maxsock = tcpsock;
268 		connect_type_cnt++;
269 	}
270 
271 	if (connect_type_cnt == 0)
272 		return (0);
273 
274 	setproctitle("master");
275 
276 	/*
277 	 * Allocate space for the fd_set pointers and fill in sockbits
278 	 */
279 	fd_size = howmany(maxsock + 1, NFDBITS) * sizeof(fd_mask);
280 	sockbits = malloc(fd_size);
281 	ready = malloc(fd_size);
282 	if (sockbits == NULL || ready == NULL) {
283 		syslog(LOG_ERR, "cannot allocate memory");
284 		return (1);
285 	}
286 	memset(sockbits, 0, fd_size);
287 	if (tcpflag)
288 		FD_SET(tcpsock, sockbits);
289 
290 	/*
291 	 * Loop forever accepting connections and passing the sockets
292 	 * into the kernel for the mounts.
293 	 */
294 	for (;;) {
295 		memcpy(ready, sockbits, fd_size);
296 		if (connect_type_cnt > 1) {
297 			if (select(maxsock + 1,
298 			    ready, NULL, NULL, NULL) < 1) {
299 				syslog(LOG_ERR, "select failed: %m");
300 				return (1);
301 			}
302 		}
303 		if (tcpflag && FD_ISSET(tcpsock, ready)) {
304 			len = sizeof(inetpeer);
305 			if ((msgsock = accept(tcpsock,
306 			    (struct sockaddr *)&inetpeer, &len)) < 0) {
307 				syslog(LOG_ERR, "accept failed: %m");
308 				return (1);
309 			}
310 			memset(inetpeer.sin_zero, 0, sizeof(inetpeer.sin_zero));
311 			if (setsockopt(msgsock, SOL_SOCKET,
312 			    SO_KEEPALIVE, &on, sizeof(on)) < 0)
313 				syslog(LOG_ERR,
314 				    "setsockopt SO_KEEPALIVE: %m");
315 			nfsdargs.sock = msgsock;
316 			nfsdargs.name = (caddr_t)&inetpeer;
317 			nfsdargs.namelen = sizeof(inetpeer);
318 			if (nfssvc(NFSSVC_ADDSOCK, &nfsdargs) < 0) {
319 				syslog(LOG_ERR, "can't Add TCP socket");
320 				return (1);
321 			}
322 			(void)close(msgsock);
323 		}
324 	}
325 }
326 
327 void
328 usage(void)
329 {
330 	(void)fprintf(stderr, "usage: nfsd [-rtu] [-n num_servers]\n");
331 	exit(1);
332 }
333 
334 /* ARGSUSED */
335 void
336 nonfs(int signo)
337 {
338 	int save_errno = errno;
339 	struct syslog_data sdata = SYSLOG_DATA_INIT;
340 
341 	syslog_r(LOG_ERR, &sdata, "missing system call: NFS not available.");
342 	errno = save_errno;
343 }
344 
345 /* ARGSUSED */
346 void
347 reapchild(int signo)
348 {
349 	int save_errno = errno;
350 
351 	while (wait3(NULL, WNOHANG, NULL) > 0)
352 		;
353 	errno = save_errno;
354 }
355