xref: /freebsd/usr.sbin/nfsd/nfsd.c (revision 2546665afcaf0d53dc2c7058fee96354b3680f5a)
1 /*
2  * Copyright (c) 1989, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Rick Macklem at The University of Guelph.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 static const char copyright[] =
39 "@(#) Copyright (c) 1989, 1993, 1994\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif /* not lint */
42 
43 #ifndef lint
44 #if 0
45 static char sccsid[] = "@(#)nfsd.c	8.9 (Berkeley) 3/29/95";
46 #endif
47 static const char rcsid[] =
48   "$FreeBSD$";
49 #endif /* not lint */
50 
51 #include <sys/param.h>
52 #include <sys/syslog.h>
53 #include <sys/wait.h>
54 #include <sys/mount.h>
55 #include <sys/linker.h>
56 #include <sys/module.h>
57 
58 #include <rpc/rpc.h>
59 #include <rpc/pmap_clnt.h>
60 
61 #include <netdb.h>
62 #include <arpa/inet.h>
63 #include <nfs/rpcv2.h>
64 #include <nfs/nfsproto.h>
65 #include <nfsserver/nfs.h>
66 
67 #include <err.h>
68 #include <errno.h>
69 #include <signal.h>
70 #include <stdio.h>
71 #include <stdlib.h>
72 #include <string.h>
73 #include <unistd.h>
74 #include <netdb.h>
75 
76 /* Global defs */
77 #ifdef DEBUG
78 #define	syslog(e, s...)	fprintf(stderr,s)
79 int	debug = 1;
80 #else
81 int	debug = 0;
82 #endif
83 
84 #define	MAXNFSDCNT	20
85 #define	DEFNFSDCNT	 4
86 pid_t	children[MAXNFSDCNT];	/* PIDs of children */
87 int	nfsdcnt;		/* number of children */
88 
89 void	cleanup(int);
90 void	child_cleanup(int);
91 void	killchildren(void);
92 void	nfsd_exit(int);
93 void	nonfs(int);
94 void	reapchild(int);
95 int	setbindhost(struct addrinfo **ia, const char *bindhost,
96 	    struct addrinfo hints);
97 void	start_server(int);
98 void	unregistration(void);
99 void	usage(void);
100 
101 /*
102  * Nfs server daemon mostly just a user context for nfssvc()
103  *
104  * 1 - do file descriptor and signal cleanup
105  * 2 - fork the nfsd(s)
106  * 3 - create server socket(s)
107  * 4 - register socket with rpcbind
108  *
109  * For connectionless protocols, just pass the socket into the kernel via.
110  * nfssvc().
111  * For connection based sockets, loop doing accepts. When you get a new
112  * socket from accept, pass the msgsock into the kernel via. nfssvc().
113  * The arguments are:
114  *	-r - reregister with rpcbind
115  *	-d - unregister with rpcbind
116  *	-t - support tcp nfs clients
117  *	-u - support udp nfs clients
118  * followed by "n" which is the number of nfsds' to fork off
119  */
120 int
121 main(argc, argv, envp)
122 	int argc;
123 	char *argv[], *envp[];
124 {
125 	struct nfsd_args nfsdargs;
126 	struct addrinfo *ai_udp, *ai_tcp, *ai_udp6, *ai_tcp6, hints;
127 	struct netconfig *nconf_udp, *nconf_tcp, *nconf_udp6, *nconf_tcp6;
128 	struct netbuf nb_udp, nb_tcp, nb_udp6, nb_tcp6;
129 	struct sockaddr_in inetpeer;
130 	struct sockaddr_in6 inet6peer;
131 	fd_set ready, sockbits;
132 	fd_set v4bits, v6bits;
133 	int ch, connect_type_cnt, i, len, maxsock, msgsock;
134 	int on = 1, unregister, reregister, sock;
135 	int tcp6sock, ip6flag, tcpflag, tcpsock;
136 	int udpflag, ecode, s, srvcnt;
137 	int bindhostc, bindanyflag, rpcbreg, rpcbregcnt;
138 	char **bindhost = NULL;
139 	pid_t pid;
140 
141 	if (modfind("nfsserver") < 0) {
142 		/* Not present in kernel, try loading it */
143 		if (kldload("nfsserver") < 0 || modfind("nfsserver") < 0)
144 			errx(1, "NFS server is not available");
145 	}
146 
147 	nfsdcnt = DEFNFSDCNT;
148 	unregister = reregister = tcpflag = maxsock = 0;
149 	bindanyflag = udpflag = connect_type_cnt = bindhostc = 0;
150 #define	GETOPT	"ah:n:rdtu"
151 #define	USAGE	"[-ardtu] [-n num_servers] [-h bindip]"
152 	while ((ch = getopt(argc, argv, GETOPT)) != -1)
153 		switch (ch) {
154 		case 'a':
155 			bindanyflag = 1;
156 			break;
157 		case 'n':
158 			nfsdcnt = atoi(optarg);
159 			if (nfsdcnt < 1 || nfsdcnt > MAXNFSDCNT) {
160 				warnx("nfsd count %d; reset to %d", nfsdcnt,
161 				    DEFNFSDCNT);
162 				nfsdcnt = DEFNFSDCNT;
163 			}
164 			break;
165 		case 'h':
166 			bindhostc++;
167 			bindhost = realloc(bindhost,sizeof(char *)*bindhostc);
168 			if (bindhost == NULL)
169 				errx(1, "Out of memory");
170 			bindhost[bindhostc-1] = strdup(optarg);
171 			if (bindhost[bindhostc-1] == NULL)
172 				errx(1, "Out of memory");
173 			break;
174 		case 'r':
175 			reregister = 1;
176 			break;
177 		case 'd':
178 			unregister = 1;
179 			break;
180 		case 't':
181 			tcpflag = 1;
182 			break;
183 		case 'u':
184 			udpflag = 1;
185 			break;
186 		default:
187 		case '?':
188 			usage();
189 		};
190 	if (!tcpflag && !udpflag)
191 		udpflag = 1;
192 	argv += optind;
193 	argc -= optind;
194 
195 	/*
196 	 * XXX
197 	 * Backward compatibility, trailing number is the count of daemons.
198 	 */
199 	if (argc > 1)
200 		usage();
201 	if (argc == 1) {
202 		nfsdcnt = atoi(argv[0]);
203 		if (nfsdcnt < 1 || nfsdcnt > MAXNFSDCNT) {
204 			warnx("nfsd count %d; reset to %d", nfsdcnt,
205 			    DEFNFSDCNT);
206 			nfsdcnt = DEFNFSDCNT;
207 		}
208 	}
209 
210 	ip6flag = 1;
211 	s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
212 	if (s == -1) {
213 		if (errno != EPROTONOSUPPORT)
214 			err(1, "socket");
215 		ip6flag = 0;
216 	} else if (getnetconfigent("udp6") == NULL ||
217 		getnetconfigent("tcp6") == NULL) {
218 		ip6flag = 0;
219 	}
220 	if (s != -1)
221 		close(s);
222 
223 	if (bindhostc == 0 || bindanyflag) {
224 		bindhostc++;
225 		bindhost = realloc(bindhost,sizeof(char *)*bindhostc);
226 		if (bindhost == NULL)
227 			errx(1, "Out of memory");
228 		bindhost[bindhostc-1] = strdup("*");
229 		if (bindhost[bindhostc-1] == NULL)
230 			errx(1, "Out of memory");
231 	}
232 
233 	if (unregister) {
234 		unregistration();
235 		exit (0);
236 	}
237 	if (reregister) {
238 		if (udpflag) {
239 			memset(&hints, 0, sizeof hints);
240 			hints.ai_flags = AI_PASSIVE;
241 			hints.ai_family = AF_INET;
242 			hints.ai_socktype = SOCK_DGRAM;
243 			hints.ai_protocol = IPPROTO_UDP;
244 			ecode = getaddrinfo(NULL, "nfs", &hints, &ai_udp);
245 			if (ecode != 0)
246 				err(1, "getaddrinfo udp: %s", gai_strerror(ecode));
247 			nconf_udp = getnetconfigent("udp");
248 			if (nconf_udp == NULL)
249 				err(1, "getnetconfigent udp failed");
250 			nb_udp.buf = ai_udp->ai_addr;
251 			nb_udp.len = nb_udp.maxlen = ai_udp->ai_addrlen;
252 			if ((!rpcb_set(RPCPROG_NFS, 2, nconf_udp, &nb_udp)) ||
253 			    (!rpcb_set(RPCPROG_NFS, 3, nconf_udp, &nb_udp)))
254 				err(1, "rpcb_set udp failed");
255 			freeaddrinfo(ai_udp);
256 		}
257 		if (udpflag && ip6flag) {
258 			memset(&hints, 0, sizeof hints);
259 			hints.ai_flags = AI_PASSIVE;
260 			hints.ai_family = AF_INET6;
261 			hints.ai_socktype = SOCK_DGRAM;
262 			hints.ai_protocol = IPPROTO_UDP;
263 			ecode = getaddrinfo(NULL, "nfs", &hints, &ai_udp6);
264 			if (ecode != 0)
265 				err(1, "getaddrinfo udp6: %s", gai_strerror(ecode));
266 			nconf_udp6 = getnetconfigent("udp6");
267 			if (nconf_udp6 == NULL)
268 				err(1, "getnetconfigent udp6 failed");
269 			nb_udp6.buf = ai_udp6->ai_addr;
270 			nb_udp6.len = nb_udp6.maxlen = ai_udp6->ai_addrlen;
271 			if ((!rpcb_set(RPCPROG_NFS, 2, nconf_udp6, &nb_udp6)) ||
272 			    (!rpcb_set(RPCPROG_NFS, 3, nconf_udp6, &nb_udp6)))
273 				err(1, "rpcb_set udp6 failed");
274 			freeaddrinfo(ai_udp6);
275 		}
276 		if (tcpflag) {
277 			memset(&hints, 0, sizeof hints);
278 			hints.ai_flags = AI_PASSIVE;
279 			hints.ai_family = AF_INET;
280 			hints.ai_socktype = SOCK_STREAM;
281 			hints.ai_protocol = IPPROTO_TCP;
282 			ecode = getaddrinfo(NULL, "nfs", &hints, &ai_tcp);
283 			if (ecode != 0)
284 				err(1, "getaddrinfo tcp: %s", gai_strerror(ecode));
285 			nconf_tcp = getnetconfigent("tcp");
286 			if (nconf_tcp == NULL)
287 				err(1, "getnetconfigent tcp failed");
288 			nb_tcp.buf = ai_tcp->ai_addr;
289 			nb_tcp.len = nb_tcp.maxlen = ai_tcp->ai_addrlen;
290 			if ((!rpcb_set(RPCPROG_NFS, 2, nconf_tcp, &nb_tcp)) ||
291 			    (!rpcb_set(RPCPROG_NFS, 3, nconf_tcp, &nb_tcp)))
292 				err(1, "rpcb_set tcp failed");
293 			freeaddrinfo(ai_tcp);
294 		}
295 		if (tcpflag && ip6flag) {
296 			memset(&hints, 0, sizeof hints);
297 			hints.ai_flags = AI_PASSIVE;
298 			hints.ai_family = AF_INET6;
299 			hints.ai_socktype = SOCK_STREAM;
300 			hints.ai_protocol = IPPROTO_TCP;
301 			ecode = getaddrinfo(NULL, "nfs", &hints, &ai_tcp6);
302 			if (ecode != 0)
303 				err(1, "getaddrinfo tcp6: %s", gai_strerror(ecode));
304 			nconf_tcp6 = getnetconfigent("tcp6");
305 			if (nconf_tcp6 == NULL)
306 				err(1, "getnetconfigent tcp6 failed");
307 			nb_tcp6.buf = ai_tcp6->ai_addr;
308 			nb_tcp6.len = nb_tcp6.maxlen = ai_tcp6->ai_addrlen;
309 			if ((!rpcb_set(RPCPROG_NFS, 2, nconf_tcp6, &nb_tcp6)) ||
310 			    (!rpcb_set(RPCPROG_NFS, 3, nconf_tcp6, &nb_tcp6)))
311 				err(1, "rpcb_set tcp6 failed");
312 			freeaddrinfo(ai_tcp6);
313 		}
314 		exit (0);
315 	}
316 	if (debug == 0) {
317 		daemon(0, 0);
318 		(void)signal(SIGHUP, SIG_IGN);
319 		(void)signal(SIGINT, SIG_IGN);
320 		/*
321 		 * nfsd sits in the kernel most of the time.  It needs
322 		 * to ignore SIGTERM/SIGQUIT in order to stay alive as long
323 		 * as possible during a shutdown, otherwise loopback
324 		 * mounts will not be able to unmount.
325 		 */
326 		(void)signal(SIGTERM, SIG_IGN);
327 		(void)signal(SIGQUIT, SIG_IGN);
328 	}
329 	(void)signal(SIGSYS, nonfs);
330 	(void)signal(SIGCHLD, reapchild);
331 
332 	openlog("nfsd", LOG_PID, LOG_DAEMON);
333 
334 	/* If we use UDP only, we start the last server below. */
335 	srvcnt = tcpflag ? nfsdcnt : nfsdcnt - 1;
336 	for (i = 0; i < srvcnt; i++) {
337 		switch ((pid = fork())) {
338 		case -1:
339 			syslog(LOG_ERR, "fork: %m");
340 			nfsd_exit(1);
341 		case 0:
342 			break;
343 		default:
344 			children[i] = pid;
345 			continue;
346 		}
347 		(void)signal(SIGUSR1, child_cleanup);
348 		setproctitle("server");
349 
350 		start_server(0);
351 	}
352 
353 	(void)signal(SIGUSR1, cleanup);
354 	FD_ZERO(&v4bits);
355 	FD_ZERO(&v6bits);
356 	FD_ZERO(&sockbits);
357 
358 	rpcbregcnt = 0;
359 	/* Set up the socket for udp and rpcb register it. */
360 	if (udpflag) {
361 		rpcbreg = 0;
362 		for (i = 0; i < bindhostc; i++) {
363 			memset(&hints, 0, sizeof hints);
364 			hints.ai_flags = AI_PASSIVE;
365 			hints.ai_family = AF_INET;
366 			hints.ai_socktype = SOCK_DGRAM;
367 			hints.ai_protocol = IPPROTO_UDP;
368 			if (setbindhost(&ai_udp, bindhost[i], hints) == 0) {
369 				rpcbreg = 1;
370 				rpcbregcnt++;
371 				if ((sock = socket(ai_udp->ai_family,
372 				    ai_udp->ai_socktype,
373 				    ai_udp->ai_protocol)) < 0) {
374 					syslog(LOG_ERR,
375 					    "can't create udp socket");
376 					nfsd_exit(1);
377 				}
378 				if (bind(sock, ai_udp->ai_addr,
379 				    ai_udp->ai_addrlen) < 0) {
380 					syslog(LOG_ERR,
381 					    "can't bind udp addr %s: %m",
382 					    bindhost[i]);
383 					nfsd_exit(1);
384 				}
385 				freeaddrinfo(ai_udp);
386 				nfsdargs.sock = sock;
387 				nfsdargs.name = NULL;
388 				nfsdargs.namelen = 0;
389 				if (nfssvc(NFSSVC_ADDSOCK, &nfsdargs) < 0) {
390 					syslog(LOG_ERR, "can't Add UDP socket");
391 					nfsd_exit(1);
392 				}
393 				(void)close(sock);
394 			}
395 		}
396 		if (rpcbreg == 1) {
397 			memset(&hints, 0, sizeof hints);
398 			hints.ai_flags = AI_PASSIVE;
399 			hints.ai_family = AF_INET;
400 			hints.ai_socktype = SOCK_DGRAM;
401 			hints.ai_protocol = IPPROTO_UDP;
402 			ecode = getaddrinfo(NULL, "nfs", &hints, &ai_udp);
403 			if (ecode != 0) {
404 				syslog(LOG_ERR, "getaddrinfo udp: %s",
405 				   gai_strerror(ecode));
406 				nfsd_exit(1);
407 			}
408 			nconf_udp = getnetconfigent("udp");
409 			if (nconf_udp == NULL)
410 				err(1, "getnetconfigent udp failed");
411 			nb_udp.buf = ai_udp->ai_addr;
412 			nb_udp.len = nb_udp.maxlen = ai_udp->ai_addrlen;
413 			if ((!rpcb_set(RPCPROG_NFS, 2, nconf_udp, &nb_udp)) ||
414 			    (!rpcb_set(RPCPROG_NFS, 3, nconf_udp, &nb_udp)))
415 				err(1, "rpcb_set udp failed");
416 			freeaddrinfo(ai_udp);
417 		}
418 	}
419 
420 	/* Set up the socket for udp6 and rpcb register it. */
421 	if (udpflag && ip6flag) {
422 		rpcbreg = 0;
423 		for (i = 0; i < bindhostc; i++) {
424 			memset(&hints, 0, sizeof hints);
425 			hints.ai_flags = AI_PASSIVE;
426 			hints.ai_family = AF_INET6;
427 			hints.ai_socktype = SOCK_DGRAM;
428 			hints.ai_protocol = IPPROTO_UDP;
429 			if (setbindhost(&ai_udp6, bindhost[i], hints) == 0) {
430 				rpcbreg = 1;
431 				rpcbregcnt++;
432 				if ((sock = socket(ai_udp6->ai_family,
433 				    ai_udp6->ai_socktype,
434 				    ai_udp6->ai_protocol)) < 0) {
435 					syslog(LOG_ERR,
436 						"can't create udp6 socket");
437 					nfsd_exit(1);
438 				}
439 				if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY,
440 				    &on, sizeof on) < 0) {
441 					syslog(LOG_ERR,
442 					    "can't set v6-only binding for "
443 					    "udp6 socket: %m");
444 					nfsd_exit(1);
445 				}
446 				if (bind(sock, ai_udp6->ai_addr,
447 				    ai_udp6->ai_addrlen) < 0) {
448 					syslog(LOG_ERR,
449 					    "can't bind udp6 addr %s: %m",
450 					    bindhost[i]);
451 					nfsd_exit(1);
452 				}
453 				freeaddrinfo(ai_udp6);
454 				nfsdargs.sock = sock;
455 				nfsdargs.name = NULL;
456 				nfsdargs.namelen = 0;
457 				if (nfssvc(NFSSVC_ADDSOCK, &nfsdargs) < 0) {
458 					syslog(LOG_ERR,
459 					    "can't add UDP6 socket");
460 					nfsd_exit(1);
461 				}
462 				(void)close(sock);
463 			}
464 		}
465 		if (rpcbreg == 1) {
466 			memset(&hints, 0, sizeof hints);
467 			hints.ai_flags = AI_PASSIVE;
468 			hints.ai_family = AF_INET6;
469 			hints.ai_socktype = SOCK_DGRAM;
470 			hints.ai_protocol = IPPROTO_UDP;
471 			ecode = getaddrinfo(NULL, "nfs", &hints, &ai_udp6);
472 			if (ecode != 0) {
473 				syslog(LOG_ERR, "getaddrinfo udp6: %s",
474 				   gai_strerror(ecode));
475 				nfsd_exit(1);
476 			}
477 			nconf_udp6 = getnetconfigent("udp6");
478 			if (nconf_udp6 == NULL)
479 				err(1, "getnetconfigent udp6 failed");
480 			nb_udp6.buf = ai_udp6->ai_addr;
481 			nb_udp6.len = nb_udp6.maxlen = ai_udp6->ai_addrlen;
482 			if ((!rpcb_set(RPCPROG_NFS, 2, nconf_udp6, &nb_udp6)) ||
483 			    (!rpcb_set(RPCPROG_NFS, 3, nconf_udp6, &nb_udp6)))
484 				err(1, "rpcb_set udp6 failed");
485 			freeaddrinfo(ai_udp6);
486 		}
487 	}
488 
489 	/* Set up the socket for tcp and rpcb register it. */
490 	if (tcpflag) {
491 		rpcbreg = 0;
492 		for (i = 0; i < bindhostc; i++) {
493 			memset(&hints, 0, sizeof hints);
494 			hints.ai_flags = AI_PASSIVE;
495 			hints.ai_family = AF_INET;
496 			hints.ai_socktype = SOCK_STREAM;
497 			hints.ai_protocol = IPPROTO_TCP;
498 			if (setbindhost(&ai_tcp, bindhost[i], hints) == 0) {
499 				rpcbreg = 1;
500 				rpcbregcnt++;
501 				if ((tcpsock = socket(AF_INET, SOCK_STREAM,
502 				    0)) < 0) {
503 					syslog(LOG_ERR,
504 					    "can't create tpc socket");
505 					nfsd_exit(1);
506 				}
507 				if (setsockopt(tcpsock, SOL_SOCKET,
508 				    SO_REUSEADDR,
509 				    (char *)&on, sizeof(on)) < 0)
510 					syslog(LOG_ERR,
511 					     "setsockopt SO_REUSEADDR: %m");
512 				if (bind(tcpsock, ai_tcp->ai_addr,
513 				    ai_tcp->ai_addrlen) < 0) {
514 					syslog(LOG_ERR,
515 					    "can't bind tcp addr %s: %m",
516 					    bindhost[i]);
517 					nfsd_exit(1);
518 				}
519 				if (listen(tcpsock, 5) < 0) {
520 					syslog(LOG_ERR, "listen failed");
521 					nfsd_exit(1);
522 				}
523 				freeaddrinfo(ai_tcp);
524 				FD_SET(tcpsock, &sockbits);
525 				FD_SET(tcpsock, &v4bits);
526 				maxsock = tcpsock;
527 				connect_type_cnt++;
528 			}
529 		}
530 		if (rpcbreg == 1) {
531 			memset(&hints, 0, sizeof hints);
532 			hints.ai_flags = AI_PASSIVE;
533 			hints.ai_family = AF_INET;
534 			hints.ai_socktype = SOCK_STREAM;
535 			hints.ai_protocol = IPPROTO_TCP;
536 			ecode = getaddrinfo(NULL, "nfs", &hints,
537 			     &ai_tcp);
538 			if (ecode != 0) {
539 				syslog(LOG_ERR, "getaddrinfo tcp: %s",
540 				   gai_strerror(ecode));
541 				nfsd_exit(1);
542 			}
543 			nconf_tcp = getnetconfigent("tcp");
544 			if (nconf_tcp == NULL)
545 				err(1, "getnetconfigent tcp failed");
546 			nb_tcp.buf = ai_tcp->ai_addr;
547 			nb_tcp.len = nb_tcp.maxlen = ai_tcp->ai_addrlen;
548 			if ((!rpcb_set(RPCPROG_NFS, 2, nconf_tcp,
549 			    &nb_tcp)) || (!rpcb_set(RPCPROG_NFS, 3,
550 			    nconf_tcp, &nb_tcp)))
551 				err(1, "rpcb_set tcp failed");
552 			freeaddrinfo(ai_tcp);
553 		}
554 	}
555 
556 	/* Set up the socket for tcp6 and rpcb register it. */
557 	if (tcpflag && ip6flag) {
558 		rpcbreg = 0;
559 		for (i = 0; i < bindhostc; i++) {
560 			memset(&hints, 0, sizeof hints);
561 			hints.ai_flags = AI_PASSIVE;
562 			hints.ai_family = AF_INET6;
563 			hints.ai_socktype = SOCK_STREAM;
564 			hints.ai_protocol = IPPROTO_TCP;
565 			if (setbindhost(&ai_tcp6, bindhost[i], hints) == 0) {
566 				rpcbreg = 1;
567 				rpcbregcnt++;
568 				if ((tcp6sock = socket(ai_tcp6->ai_family,
569 				    ai_tcp6->ai_socktype,
570 				    ai_tcp6->ai_protocol)) < 0) {
571 					syslog(LOG_ERR,
572 					    "can't create tcp6 socket");
573 					nfsd_exit(1);
574 				}
575 				if (setsockopt(tcp6sock, SOL_SOCKET,
576 				    SO_REUSEADDR,
577 				    (char *)&on, sizeof(on)) < 0)
578 					syslog(LOG_ERR,
579 					    "setsockopt SO_REUSEADDR: %m");
580 				if (setsockopt(tcp6sock, IPPROTO_IPV6,
581 				    IPV6_V6ONLY, &on, sizeof on) < 0) {
582 					syslog(LOG_ERR,
583 					"can't set v6-only binding for tcp6 "
584 					    "socket: %m");
585 					nfsd_exit(1);
586 				}
587 				if (bind(tcp6sock, ai_tcp6->ai_addr,
588 				    ai_tcp6->ai_addrlen) < 0) {
589 					syslog(LOG_ERR,
590 					    "can't bind tcp6 addr %s: %m",
591 					    bindhost[i]);
592 					nfsd_exit(1);
593 				}
594 				if (listen(tcp6sock, 5) < 0) {
595 					syslog(LOG_ERR, "listen failed");
596 					nfsd_exit(1);
597 				}
598 				freeaddrinfo(ai_tcp6);
599 				FD_SET(tcp6sock, &sockbits);
600 				FD_SET(tcp6sock, &v6bits);
601 				if (maxsock < tcp6sock)
602 					maxsock = tcp6sock;
603 				connect_type_cnt++;
604 			}
605 		}
606 		if (rpcbreg == 1) {
607 			memset(&hints, 0, sizeof hints);
608 			hints.ai_flags = AI_PASSIVE;
609 			hints.ai_family = AF_INET6;
610 			hints.ai_socktype = SOCK_STREAM;
611 			hints.ai_protocol = IPPROTO_TCP;
612 			ecode = getaddrinfo(NULL, "nfs", &hints, &ai_tcp6);
613 			if (ecode != 0) {
614 				syslog(LOG_ERR, "getaddrinfo tcp6: %s",
615 				   gai_strerror(ecode));
616 				nfsd_exit(1);
617 			}
618 			nconf_tcp6 = getnetconfigent("tcp6");
619 			if (nconf_tcp6 == NULL)
620 				err(1, "getnetconfigent tcp6 failed");
621 			nb_tcp6.buf = ai_tcp6->ai_addr;
622 			nb_tcp6.len = nb_tcp6.maxlen = ai_tcp6->ai_addrlen;
623 			if ((!rpcb_set(RPCPROG_NFS, 2, nconf_tcp6, &nb_tcp6)) ||
624 			    (!rpcb_set(RPCPROG_NFS, 3, nconf_tcp6, &nb_tcp6)))
625 				err(1, "rpcb_set tcp6 failed");
626 			freeaddrinfo(ai_tcp6);
627 		}
628 	}
629 
630 	if (rpcbregcnt == 0) {
631 		syslog(LOG_ERR, "rpcb_set() failed, nothing to do: %m");
632 		nfsd_exit(1);
633 	}
634 
635 	if (tcpflag && connect_type_cnt == 0) {
636 		syslog(LOG_ERR, "tcp connects == 0, nothing to do: %m");
637 		nfsd_exit(1);
638 	}
639 
640 	setproctitle("master");
641 	/*
642 	 * We always want a master to have a clean way to to shut nfsd down
643 	 * (with unregistration): if the master is killed, it unregisters and
644 	 * kills all children. If we run for UDP only (and so do not have to
645 	 * loop waiting waiting for accept), we instead make the parent
646 	 * a "server" too. start_server will not return.
647 	 */
648 	if (!tcpflag)
649 		start_server(1);
650 
651 	/*
652 	 * Loop forever accepting connections and passing the sockets
653 	 * into the kernel for the mounts.
654 	 */
655 	for (;;) {
656 		ready = sockbits;
657 		if (connect_type_cnt > 1) {
658 			if (select(maxsock + 1,
659 			    &ready, NULL, NULL, NULL) < 1) {
660 				syslog(LOG_ERR, "select failed: %m");
661 				if (errno == EINTR)
662 					continue;
663 				nfsd_exit(1);
664 			}
665 		}
666 		for (tcpsock = 0; tcpsock <= maxsock; tcpsock++) {
667 			if (FD_ISSET(tcpsock, &ready)) {
668 				if (FD_ISSET(tcpsock, &v4bits)) {
669 					len = sizeof(inetpeer);
670 					if ((msgsock = accept(tcpsock,
671 					    (struct sockaddr *)&inetpeer, &len)) < 0) {
672 						syslog(LOG_ERR, "accept failed: %m");
673 						if (errno == ECONNABORTED ||
674 						    errno == EINTR)
675 							continue;
676 						nfsd_exit(1);
677 					}
678 					memset(inetpeer.sin_zero, 0,
679 						sizeof(inetpeer.sin_zero));
680 					if (setsockopt(msgsock, SOL_SOCKET,
681 					    SO_KEEPALIVE, (char *)&on, sizeof(on)) < 0)
682 						syslog(LOG_ERR,
683 						    "setsockopt SO_KEEPALIVE: %m");
684 					nfsdargs.sock = msgsock;
685 					nfsdargs.name = (caddr_t)&inetpeer;
686 					nfsdargs.namelen = len;
687 					nfssvc(NFSSVC_ADDSOCK, &nfsdargs);
688 					(void)close(msgsock);
689 				} else if (FD_ISSET(tcpsock, &v6bits)) {
690 					len = sizeof(inet6peer);
691 					if ((msgsock = accept(tcpsock,
692 					    (struct sockaddr *)&inet6peer,
693 					    &len)) < 0) {
694 						syslog(LOG_ERR,
695 						     "accept failed: %m");
696 						if (errno == ECONNABORTED ||
697 						    errno == EINTR)
698 							continue;
699 						nfsd_exit(1);
700 					}
701 					if (setsockopt(msgsock, SOL_SOCKET,
702 					    SO_KEEPALIVE, (char *)&on,
703 					    sizeof(on)) < 0)
704 						syslog(LOG_ERR, "setsockopt "
705 						    "SO_KEEPALIVE: %m");
706 					nfsdargs.sock = msgsock;
707 					nfsdargs.name = (caddr_t)&inet6peer;
708 					nfsdargs.namelen = len;
709 					nfssvc(NFSSVC_ADDSOCK, &nfsdargs);
710 					(void)close(msgsock);
711 				}
712 			}
713 		}
714 	}
715 }
716 
717 int
718 setbindhost(struct addrinfo **ai, const char *bindhost, struct addrinfo hints)
719 {
720 	int ecode;
721 	u_int32_t host_addr[4];  /* IPv4 or IPv6 */
722 	const char *hostptr;
723 
724 	if (bindhost == NULL || strcmp("*", bindhost) == 0)
725 		hostptr = NULL;
726 	else
727 		hostptr = bindhost;
728 
729 	if (hostptr != NULL) {
730 		switch (hints.ai_family) {
731 		case AF_INET:
732 			if (inet_pton(AF_INET, hostptr, host_addr) == 1) {
733 				hints.ai_flags = AI_NUMERICHOST;
734 			} else {
735 				if (inet_pton(AF_INET6, hostptr,
736 				    host_addr) == 1)
737 					return (1);
738 			}
739 			break;
740 		case AF_INET6:
741 			if (inet_pton(AF_INET6, hostptr, host_addr) == 1) {
742 				hints.ai_flags = AI_NUMERICHOST;
743 			} else {
744 				if (inet_pton(AF_INET, hostptr,
745 				    host_addr) == 1)
746 					return (1);
747 			}
748 			break;
749 		default:
750 			break;
751 		}
752 	}
753 
754 	ecode = getaddrinfo(hostptr, "nfs", &hints, ai);
755 	if (ecode != 0) {
756 		syslog(LOG_ERR, "getaddrinfo %s: %s", bindhost,
757 		    gai_strerror(ecode));
758 		return (1);
759 	}
760 	return (0);
761 }
762 
763 void
764 usage()
765 {
766 	(void)fprintf(stderr, "usage: nfsd %s\n", USAGE);
767 	exit(1);
768 }
769 
770 void
771 nonfs(signo)
772 	int signo;
773 {
774 	syslog(LOG_ERR, "missing system call: NFS not available");
775 }
776 
777 void
778 reapchild(signo)
779 	int signo;
780 {
781 	pid_t pid;
782 	int i;
783 
784 	while ((pid = wait3(NULL, WNOHANG, NULL)) > 0) {
785 		for (i = 0; i < nfsdcnt; i++)
786 			if (pid == children[i])
787 				children[i] = -1;
788 	}
789 }
790 
791 void
792 unregistration()
793 {
794 	if ((!rpcb_unset(RPCPROG_NFS, 2, NULL)) ||
795 	    (!rpcb_unset(RPCPROG_NFS, 3, NULL)))
796 		syslog(LOG_ERR, "rpcb_unset failed");
797 }
798 
799 void
800 killchildren()
801 {
802 	int i;
803 
804 	for (i = 0; i < nfsdcnt; i++) {
805 		if (children[i] > 0)
806 			kill(children[i], SIGKILL);
807 	}
808 }
809 
810 /*
811  * Cleanup master after SIGUSR1.
812  */
813 void
814 cleanup(signo)
815 {
816 	nfsd_exit(0);
817 }
818 
819 /*
820  * Cleanup child after SIGUSR1.
821  */
822 void
823 child_cleanup(signo)
824 {
825 	exit(0);
826 }
827 
828 void
829 nfsd_exit(int status)
830 {
831 	killchildren();
832 	unregistration();
833 	exit(status);
834 }
835 
836 void
837 start_server(int master)
838 {
839 	int status;
840 
841 	status = 0;
842 	if (nfssvc(NFSSVC_NFSD, NULL) < 0) {
843 		syslog(LOG_ERR, "nfssvc: %m");
844 		status = 1;
845 	}
846 	if (master)
847 		nfsd_exit(status);
848 	else
849 		exit(status);
850 }
851