xref: /openbsd/sbin/nfsd/nfsd.c (revision fc61954a)
1 /*	$OpenBSD: nfsd.c,v 1.36 2016/06/07 01:29:38 tedu 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/ioctl.h>
37 #include <sys/stat.h>
38 #include <sys/wait.h>
39 #include <sys/uio.h>
40 #include <sys/ucred.h>
41 #include <sys/mount.h>
42 #include <sys/socket.h>
43 #include <sys/socketvar.h>
44 
45 #include <rpc/rpc.h>
46 #include <rpc/pmap_clnt.h>
47 #include <rpc/pmap_prot.h>
48 
49 #include <nfs/rpcv2.h>
50 #include <nfs/nfsproto.h>
51 #include <nfs/nfs.h>
52 
53 #include <err.h>
54 #include <errno.h>
55 #include <fcntl.h>
56 #include <grp.h>
57 #include <pwd.h>
58 #include <signal.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <syslog.h>
63 #include <unistd.h>
64 
65 /* Global defs */
66 #ifdef DEBUG
67 #define	syslog(e, s)	fprintf(stderr,(s))
68 int	debug = 1;
69 #else
70 int	debug = 0;
71 #endif
72 
73 struct	nfsd_srvargs nsd;
74 
75 void	nonfs(int);
76 void	reapchild(int);
77 void	usage(void);
78 
79 #define	MAXNFSDCNT	20
80 #define	DEFNFSDCNT	 4
81 
82 /*
83  * Nfs server daemon mostly just a user context for nfssvc()
84  *
85  * 1 - do file descriptor and signal cleanup
86  * 2 - fork the nfsd(s)
87  * 3 - create server socket(s)
88  * 4 - register socket with portmap
89  *
90  * For connectionless protocols, just pass the socket into the kernel via.
91  * nfssvc().
92  * For connection based sockets, loop doing accepts. When you get a new
93  * socket from accept, pass the msgsock into the kernel via. nfssvc().
94  * The arguments are:
95  *	-r - reregister with portmapper
96  *	-t - support tcp nfs clients
97  *	-u - support udp nfs clients
98  * followed by "n" which is the number of nfsds' to fork off
99  */
100 int
101 main(int argc, char *argv[])
102 {
103 	struct nfsd_args nfsdargs;
104 	struct sockaddr_in inetaddr;
105 	int ch, connect_type_cnt, i;
106 	int nfsdcnt = DEFNFSDCNT, on, reregister = 0, sock;
107 	int udpflag = 0, tcpflag = 0, tcpsock;
108 	const char *errstr = NULL;
109 
110 	/* Start by writing to both console and log. */
111 	openlog("nfsd", LOG_PID | LOG_PERROR, LOG_DAEMON);
112 
113 	if (argc == 1)
114 		udpflag = 1;
115 	while ((ch = getopt(argc, argv, "n:rtu")) != -1)
116 		switch (ch) {
117 		case 'n':
118 			nfsdcnt = strtonum(optarg, 1, MAXNFSDCNT, &errstr);
119 			if (errstr) {
120 				syslog(LOG_ERR, "nfsd count is %s: %s", errstr, optarg);
121 				return(1);
122 			}
123 			break;
124 		case 'r':
125 			reregister = 1;
126 			break;
127 		case 't':
128 			tcpflag = 1;
129 			break;
130 		case 'u':
131 			udpflag = 1;
132 			break;
133 		default:
134 			usage();
135 		};
136 	argv += optind;
137 	argc -= optind;
138 
139 	/*
140 	 * XXX
141 	 * Backward compatibility, trailing number is the count of daemons.
142 	 */
143 	if (argc > 1)
144 		usage();
145 	if (argc == 1) {
146 		nfsdcnt = strtonum(argv[0], 1, MAXNFSDCNT, &errstr);
147 		if (errstr) {
148 			syslog(LOG_ERR, "nfsd count is %s: %s", errstr, optarg);
149 			return(1);
150 		}
151 	}
152 
153 	if (debug == 0) {
154 		daemon(0, 0);
155 		(void)signal(SIGHUP, SIG_IGN);
156 		(void)signal(SIGINT, SIG_IGN);
157 		(void)signal(SIGQUIT, SIG_IGN);
158 		(void)signal(SIGSYS, nonfs);
159 	}
160 	(void)signal(SIGCHLD, reapchild);
161 
162 	if (reregister) {
163 		if (udpflag &&
164 		    (!pmap_set(RPCPROG_NFS, 2, IPPROTO_UDP, NFS_PORT) ||
165 		     !pmap_set(RPCPROG_NFS, 3, IPPROTO_UDP, NFS_PORT))) {
166 			syslog(LOG_ERR, "can't register with portmap for UDP (%m).");
167 			return (1);
168 		}
169 		if (tcpflag &&
170 		    (!pmap_set(RPCPROG_NFS, 2, IPPROTO_TCP, NFS_PORT) ||
171 		     !pmap_set(RPCPROG_NFS, 3, IPPROTO_TCP, NFS_PORT))) {
172 			syslog(LOG_ERR, "can't register with portmap for TCP (%m).");
173 			return (1);
174 		}
175 		return (0);
176 	}
177 
178 	/* Cut back to writing to log only. */
179 	closelog();
180 	openlog("nfsd", LOG_PID, LOG_DAEMON);
181 
182 	for (i = 0; i < nfsdcnt; i++) {
183 		switch (fork()) {
184 		case -1:
185 			syslog(LOG_ERR, "fork: %m");
186 			return (1);
187 		case 0:
188 			break;
189 		default:
190 			continue;
191 		}
192 
193 		setproctitle("server");
194 		nsd.nsd_nfsd = NULL;
195 		if (nfssvc(NFSSVC_NFSD, &nsd) < 0) {
196 			syslog(LOG_ERR, "nfssvc: %m");
197 			return (1);
198 		}
199 		return (0);
200 	}
201 
202 	/* If we are serving udp, set up the socket. */
203 	if (udpflag) {
204 		if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
205 			syslog(LOG_ERR, "can't create udp socket");
206 			return (1);
207 		}
208 		memset(&inetaddr, 0, sizeof inetaddr);
209 		inetaddr.sin_family = AF_INET;
210 		inetaddr.sin_addr.s_addr = INADDR_ANY;
211 		inetaddr.sin_port = htons(NFS_PORT);
212 		inetaddr.sin_len = sizeof(inetaddr);
213 		if (bind(sock, (struct sockaddr *)&inetaddr,
214 		    sizeof(inetaddr)) < 0) {
215 			syslog(LOG_ERR, "can't bind udp addr");
216 			return (1);
217 		}
218 		if (!pmap_set(RPCPROG_NFS, 2, IPPROTO_UDP, NFS_PORT) ||
219 		    !pmap_set(RPCPROG_NFS, 3, IPPROTO_UDP, NFS_PORT)) {
220 			syslog(LOG_ERR, "can't register with udp portmap");
221 			return (1);
222 		}
223 		nfsdargs.sock = sock;
224 		nfsdargs.name = NULL;
225 		nfsdargs.namelen = 0;
226 		if (nfssvc(NFSSVC_ADDSOCK, &nfsdargs) < 0) {
227 			syslog(LOG_ERR, "can't Add UDP socket");
228 			return (1);
229 		}
230 		(void)close(sock);
231 	}
232 
233 	/* Now set up the master server socket waiting for tcp connections. */
234 	on = 1;
235 	connect_type_cnt = 0;
236 	if (tcpflag) {
237 		if ((tcpsock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
238 			syslog(LOG_ERR, "can't create tcp socket");
239 			return (1);
240 		}
241 		if (setsockopt(tcpsock,
242 		    SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
243 			syslog(LOG_ERR, "setsockopt SO_REUSEADDR: %m");
244 		memset(&inetaddr, 0, sizeof inetaddr);
245 		inetaddr.sin_family = AF_INET;
246 		inetaddr.sin_addr.s_addr = INADDR_ANY;
247 		inetaddr.sin_port = htons(NFS_PORT);
248 		inetaddr.sin_len = sizeof(inetaddr);
249 		if (bind(tcpsock, (struct sockaddr *)&inetaddr,
250 		    sizeof (inetaddr)) < 0) {
251 			syslog(LOG_ERR, "can't bind tcp addr");
252 			return (1);
253 		}
254 		if (listen(tcpsock, 5) < 0) {
255 			syslog(LOG_ERR, "listen failed");
256 			return (1);
257 		}
258 		if (!pmap_set(RPCPROG_NFS, 2, IPPROTO_TCP, NFS_PORT) ||
259 		    !pmap_set(RPCPROG_NFS, 3, IPPROTO_TCP, NFS_PORT)) {
260 			syslog(LOG_ERR, "can't register tcp with portmap");
261 			return (1);
262 		}
263 		connect_type_cnt++;
264 	}
265 
266 	if (connect_type_cnt == 0)
267 		return (0);
268 
269 	setproctitle("master");
270 
271 	/*
272 	 * Loop forever accepting connections and passing the sockets
273 	 * into the kernel for the mounts.
274 	 */
275 	for (;;) {
276 		struct pollfd		pfd;
277 		struct sockaddr_in	inetpeer;
278 		int ret, msgsock;
279 		socklen_t len;
280 
281 		pfd.fd = tcpsock;
282 		pfd.events = POLLIN;
283 
284 		if (connect_type_cnt > 1) {
285 			ret = poll(&pfd, 1, INFTIM);
286 			if (ret < 1) {
287 				syslog(LOG_ERR, "poll failed: %m");
288 				return (1);
289 			}
290 
291 		}
292 
293 		if (tcpflag) {
294 			len = sizeof(inetpeer);
295 			if ((msgsock = accept(tcpsock,
296 			    (struct sockaddr *)&inetpeer, &len)) < 0) {
297 				if (errno == EWOULDBLOCK || errno == EINTR ||
298 				    errno == ECONNABORTED)
299 					continue;
300 				syslog(LOG_ERR, "accept failed: %m");
301 				return (1);
302 			}
303 			memset(inetpeer.sin_zero, 0, sizeof(inetpeer.sin_zero));
304 			if (setsockopt(msgsock, SOL_SOCKET,
305 			    SO_KEEPALIVE, &on, sizeof(on)) < 0)
306 				syslog(LOG_ERR,
307 				    "setsockopt SO_KEEPALIVE: %m");
308 			nfsdargs.sock = msgsock;
309 			nfsdargs.name = (caddr_t)&inetpeer;
310 			nfsdargs.namelen = sizeof(inetpeer);
311 			if (nfssvc(NFSSVC_ADDSOCK, &nfsdargs) < 0) {
312 				syslog(LOG_ERR, "can't Add TCP socket");
313 				return (1);
314 			}
315 			(void)close(msgsock);
316 		}
317 	}
318 }
319 
320 void
321 usage(void)
322 {
323 	(void)fprintf(stderr, "usage: nfsd [-rtu] [-n num_servers]\n");
324 	exit(1);
325 }
326 
327 /* ARGSUSED */
328 void
329 nonfs(int signo)
330 {
331 	int save_errno = errno;
332 	struct syslog_data sdata = SYSLOG_DATA_INIT;
333 
334 	syslog_r(LOG_ERR, &sdata, "missing system call: NFS not available.");
335 	errno = save_errno;
336 }
337 
338 /* ARGSUSED */
339 void
340 reapchild(int signo)
341 {
342 	int save_errno = errno;
343 
344 	while (wait3(NULL, WNOHANG, NULL) > 0)
345 		continue;
346 	errno = save_errno;
347 }
348