xref: /freebsd/usr.sbin/mountd/mountd.c (revision 5521ff5a4d1929056e7ffc982fac3341ca54df7c)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Herb Hasler and 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\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[] = "@(#)mountd.c	8.15 (Berkeley) 5/1/95";
46 #endif
47 static const char rcsid[] =
48   "$FreeBSD$";
49 #endif /*not lint*/
50 
51 #include <sys/param.h>
52 #include <sys/mount.h>
53 #include <sys/fcntl.h>
54 #include <sys/stat.h>
55 #include <sys/syslog.h>
56 #include <sys/sysctl.h>
57 
58 #include <rpc/rpc.h>
59 #include <rpc/pmap_clnt.h>
60 #include <rpc/pmap_prot.h>
61 #include <rpcsvc/mount.h>
62 #include <nfs/rpcv2.h>
63 #include <nfs/nfsproto.h>
64 #include <nfs/nfs.h>
65 #include <ufs/ufs/ufsmount.h>
66 #include <fs/msdosfs/msdosfsmount.h>
67 #include <fs/ntfs/ntfsmount.h>
68 #include <isofs/cd9660/cd9660_mount.h>	/* XXX need isofs in include */
69 
70 #include <arpa/inet.h>
71 
72 #include <ctype.h>
73 #include <err.h>
74 #include <errno.h>
75 #include <grp.h>
76 #include <netdb.h>
77 #include <pwd.h>
78 #include <signal.h>
79 #include <stdio.h>
80 #include <stdlib.h>
81 #include <string.h>
82 #include <unistd.h>
83 #include "pathnames.h"
84 
85 #ifdef DEBUG
86 #include <stdarg.h>
87 #endif
88 
89 #ifndef MOUNTDLOCK
90 #define MOUNTDLOCK "/var/run/mountd.lock"
91 #endif
92 
93 /*
94  * Structures for keeping the mount list and export list
95  */
96 struct mountlist {
97 	struct mountlist *ml_next;
98 	char	ml_host[RPCMNT_NAMELEN+1];
99 	char	ml_dirp[RPCMNT_PATHLEN+1];
100 };
101 
102 struct dirlist {
103 	struct dirlist	*dp_left;
104 	struct dirlist	*dp_right;
105 	int		dp_flag;
106 	struct hostlist	*dp_hosts;	/* List of hosts this dir exported to */
107 	char		dp_dirp[1];	/* Actually malloc'd to size of dir */
108 };
109 /* dp_flag bits */
110 #define	DP_DEFSET	0x1
111 #define DP_HOSTSET	0x2
112 #define DP_KERB		0x4
113 
114 struct exportlist {
115 	struct exportlist *ex_next;
116 	struct dirlist	*ex_dirl;
117 	struct dirlist	*ex_defdir;
118 	int		ex_flag;
119 	fsid_t		ex_fs;
120 	char		*ex_fsdir;
121 	char		*ex_indexfile;
122 };
123 /* ex_flag bits */
124 #define	EX_LINKED	0x1
125 
126 struct netmsk {
127 	struct sockaddr_storage nt_net;
128 	struct sockaddr_storage nt_mask;
129 	char		*nt_name;
130 };
131 
132 union grouptypes {
133 	struct addrinfo *gt_addrinfo;
134 	struct netmsk	gt_net;
135 };
136 
137 struct grouplist {
138 	int gr_type;
139 	union grouptypes gr_ptr;
140 	struct grouplist *gr_next;
141 };
142 /* Group types */
143 #define	GT_NULL		0x0
144 #define	GT_HOST		0x1
145 #define	GT_NET		0x2
146 #define	GT_DEFAULT	0x3
147 #define GT_IGNORE	0x5
148 
149 struct hostlist {
150 	int		 ht_flag;	/* Uses DP_xx bits */
151 	struct grouplist *ht_grp;
152 	struct hostlist	 *ht_next;
153 };
154 
155 struct fhreturn {
156 	int	fhr_flag;
157 	int	fhr_vers;
158 	nfsfh_t	fhr_fh;
159 };
160 
161 /* Global defs */
162 char	*add_expdir __P((struct dirlist **, char *, int));
163 void	add_dlist __P((struct dirlist **, struct dirlist *,
164 				struct grouplist *, int));
165 void	add_mlist __P((char *, char *));
166 int	check_dirpath __P((char *));
167 int	check_options __P((struct dirlist *));
168 int	checkmask(struct sockaddr *sa);
169 int	chk_host __P((struct dirlist *, struct sockaddr *, int *, int *));
170 void	del_mlist(char *hostp, char *dirp);
171 struct dirlist *dirp_search __P((struct dirlist *, char *));
172 int	do_mount __P((struct exportlist *, struct grouplist *, int,
173 		struct xucred *, char *, int, struct statfs *));
174 int	do_opt __P((char **, char **, struct exportlist *, struct grouplist *,
175 				int *, int *, struct xucred *));
176 struct	exportlist *ex_search __P((fsid_t *));
177 struct	exportlist *get_exp __P((void));
178 void	free_dir __P((struct dirlist *));
179 void	free_exp __P((struct exportlist *));
180 void	free_grp __P((struct grouplist *));
181 void	free_host __P((struct hostlist *));
182 void	get_exportlist __P((void));
183 int	get_host __P((char *, struct grouplist *, struct grouplist *));
184 struct hostlist *get_ht __P((void));
185 int	get_line __P((void));
186 void	get_mountlist __P((void));
187 int	get_net __P((char *, struct netmsk *, int));
188 void	getexp_err __P((struct exportlist *, struct grouplist *));
189 struct grouplist *get_grp __P((void));
190 void	hang_dirp __P((struct dirlist *, struct grouplist *,
191 				struct exportlist *, int));
192 void	huphandler(int sig);
193 int	makemask(struct sockaddr_storage *ssp, int bitlen);
194 void	mntsrv __P((struct svc_req *, SVCXPRT *));
195 void	nextfield __P((char **, char **));
196 void	out_of_mem __P((void));
197 void	parsecred __P((char *, struct xucred *));
198 int	put_exlist __P((struct dirlist *, XDR *, struct dirlist *, int *));
199 void	*sa_rawaddr(struct sockaddr *sa, int *nbytes);
200 int	sacmp(struct sockaddr *sa1, struct sockaddr *sa2,
201     struct sockaddr *samask);
202 int	scan_tree __P((struct dirlist *, struct sockaddr *));
203 static void usage __P((void));
204 int	xdr_dir __P((XDR *, char *));
205 int	xdr_explist __P((XDR *, caddr_t));
206 int	xdr_fhs __P((XDR *, caddr_t));
207 int	xdr_mlist __P((XDR *, caddr_t));
208 void	terminate __P((int));
209 
210 struct exportlist *exphead;
211 struct mountlist *mlhead;
212 struct grouplist *grphead;
213 char exname[MAXPATHLEN];
214 struct xucred def_anon = {
215 	0,
216 	(uid_t)-2,
217 	1,
218 	{ (gid_t)-2 },
219 	NULL
220 };
221 int force_v2 = 0;
222 int resvport_only = 1;
223 int dir_only = 1;
224 int log = 0;
225 int got_sighup = 0;
226 
227 int opt_flags;
228 static int have_v6 = 1;
229 #ifdef NI_WITHSCOPEID
230 static const int ninumeric = NI_NUMERICHOST | NI_WITHSCOPEID;
231 #else
232 static const int ninumeric = NI_NUMERICHOST;
233 #endif
234 
235 int mountdlockfd;
236 /* Bits for opt_flags above */
237 #define	OP_MAPROOT	0x01
238 #define	OP_MAPALL	0x02
239 #define	OP_KERB		0x04
240 #define	OP_MASK		0x08
241 #define	OP_NET		0x10
242 #define	OP_ALLDIRS	0x40
243 #define	OP_HAVEMASK	0x80	/* A mask was specified or inferred. */
244 #define OP_MASKLEN	0x200
245 
246 #ifdef DEBUG
247 int debug = 1;
248 void	SYSLOG __P((int, const char *, ...));
249 #define syslog SYSLOG
250 #else
251 int debug = 0;
252 #endif
253 
254 /*
255  * Mountd server for NFS mount protocol as described in:
256  * NFS: Network File System Protocol Specification, RFC1094, Appendix A
257  * The optional arguments are the exports file name
258  * default: _PATH_EXPORTS
259  * and "-n" to allow nonroot mount.
260  */
261 int
262 main(argc, argv)
263 	int argc;
264 	char **argv;
265 {
266 	fd_set readfds;
267 	SVCXPRT *udptransp, *tcptransp, *udp6transp, *tcp6transp;
268 	struct netconfig *udpconf, *tcpconf, *udp6conf, *tcp6conf;
269 	int udpsock, tcpsock, udp6sock, tcp6sock;
270 	int xcreated = 0, s;
271 	int one = 1;
272 	int c, error, mib[3];
273 	struct vfsconf vfc;
274 
275 	udp6conf = tcp6conf = NULL;
276 	udp6sock = tcp6sock = NULL;
277 
278 	/* Check that another mountd isn't already running. */
279 	if ((mountdlockfd = (open(MOUNTDLOCK, O_RDONLY|O_CREAT, 0444))) == -1)
280 		err(1, "%s", MOUNTDLOCK);
281 
282 	if(flock(mountdlockfd, LOCK_EX|LOCK_NB) == -1 && errno == EWOULDBLOCK)
283 		errx(1, "another rpc.mountd is already running. Aborting");
284 	s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
285 	if (s < 0)
286 		have_v6 = 0;
287 	else
288 		close(s);
289 	error = getvfsbyname("nfs", &vfc);
290 	if (error && vfsisloadable("nfs")) {
291 		if(vfsload("nfs"))
292 			err(1, "vfsload(nfs)");
293 		endvfsent();	/* flush cache */
294 		error = getvfsbyname("nfs", &vfc);
295 	}
296 	if (error)
297 		errx(1, "NFS support is not available in the running kernel");
298 
299 	while ((c = getopt(argc, argv, "2dlnr")) != -1)
300 		switch (c) {
301 		case '2':
302 			force_v2 = 1;
303 			break;
304 		case 'n':
305 			resvport_only = 0;
306 			break;
307 		case 'r':
308 			dir_only = 0;
309 			break;
310 		case 'd':
311 			debug = debug ? 0 : 1;
312 			break;
313 		case 'l':
314 			log = 1;
315 			break;
316 		default:
317 			usage();
318 		};
319 	argc -= optind;
320 	argv += optind;
321 	grphead = (struct grouplist *)NULL;
322 	exphead = (struct exportlist *)NULL;
323 	mlhead = (struct mountlist *)NULL;
324 	if (argc == 1) {
325 		strncpy(exname, *argv, MAXPATHLEN-1);
326 		exname[MAXPATHLEN-1] = '\0';
327 	} else
328 		strcpy(exname, _PATH_EXPORTS);
329 	openlog("mountd", LOG_PID, LOG_DAEMON);
330 	if (debug)
331 		warnx("getting export list");
332 	get_exportlist();
333 	if (debug)
334 		warnx("getting mount list");
335 	get_mountlist();
336 	if (debug)
337 		warnx("here we go");
338 	if (debug == 0) {
339 		daemon(0, 0);
340 		signal(SIGINT, SIG_IGN);
341 		signal(SIGQUIT, SIG_IGN);
342 	}
343 	signal(SIGHUP, huphandler);
344 	signal(SIGTERM, terminate);
345 	{ FILE *pidfile = fopen(_PATH_MOUNTDPID, "w");
346 	  if (pidfile != NULL) {
347 		fprintf(pidfile, "%d\n", getpid());
348 		fclose(pidfile);
349 	  }
350 	}
351 	rpcb_unset(RPCPROG_MNT, RPCMNT_VER1, NULL);
352 	rpcb_unset(RPCPROG_MNT, RPCMNT_VER3, NULL);
353 	udpsock  = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
354 	tcpsock  = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
355 	udpconf  = getnetconfigent("udp");
356 	tcpconf  = getnetconfigent("tcp");
357 	if (!have_v6)
358 		goto skip_v6;
359 	udp6sock = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
360 	tcp6sock = socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP);
361 	/*
362 	 * We're doing host-based access checks here, so don't allow
363 	 * v4-in-v6 to confuse things. The kernel will disable it
364 	 * by default on NFS sockets too.
365 	 */
366 	if (udp6sock != -1 && setsockopt(udp6sock, IPPROTO_IPV6,
367 		IPV6_BINDV6ONLY, &one, sizeof one) < 0){
368 		syslog(LOG_ERR, "can't disable v4-in-v6 on UDP socket");
369 		exit(1);
370 	}
371 	if (tcp6sock != -1 && setsockopt(tcp6sock, IPPROTO_IPV6,
372 		IPV6_BINDV6ONLY, &one, sizeof one) < 0){
373 		syslog(LOG_ERR, "can't disable v4-in-v6 on UDP socket");
374 		exit(1);
375 	}
376 	udp6conf = getnetconfigent("udp6");
377 	tcp6conf = getnetconfigent("tcp6");
378 
379 skip_v6:
380 	if (!resvport_only) {
381 		mib[0] = CTL_VFS;
382 		mib[1] = vfc.vfc_typenum;
383 		mib[2] = NFS_NFSPRIVPORT;
384 		if (sysctl(mib, 3, NULL, NULL, &resvport_only,
385 		    sizeof(resvport_only)) != 0 && errno != ENOENT) {
386 			syslog(LOG_ERR, "sysctl: %m");
387 			exit(1);
388 		}
389 	}
390 	if ((udptransp = svcudp_create(RPC_ANYSOCK)) == NULL ||
391 	    (tcptransp = svctcp_create(RPC_ANYSOCK, 0, 0)) == NULL) {
392 		syslog(LOG_ERR, "can't create socket");
393 		exit(1);
394 	}
395 	if (udpsock != -1 && udpconf != NULL) {
396 		bindresvport(udpsock, NULL);
397 		udptransp = svc_dg_create(udpsock, 0, 0);
398 		if (udptransp != NULL) {
399 			if (!svc_reg(udptransp, RPCPROG_MNT, RPCMNT_VER1,
400 			    mntsrv, udpconf))
401 				syslog(LOG_WARNING, "can't register UDP RPCMNT_VER1 service");
402 			else
403 				xcreated++;
404 			if (!force_v2) {
405 				if (!svc_reg(udptransp, RPCPROG_MNT, RPCMNT_VER3,
406 				    mntsrv, udpconf))
407 					syslog(LOG_WARNING, "can't register UDP RPCMNT_VER3 service");
408 				else
409 					xcreated++;
410 			}
411 		} else
412 			syslog(LOG_WARNING, "can't create UDP services");
413 
414 	}
415 	if (tcpsock != -1 && tcpconf != NULL) {
416 		bindresvport(tcpsock, NULL);
417 		listen(tcpsock, SOMAXCONN);
418 		tcptransp = svc_vc_create(tcpsock, 0, 0);
419 		if (tcptransp != NULL) {
420 			if (!svc_reg(tcptransp, RPCPROG_MNT, RPCMNT_VER1,
421 			    mntsrv, tcpconf))
422 				syslog(LOG_WARNING, "can't register TCP RPCMNT_VER1 service");
423 			else
424 				xcreated++;
425 			if (!force_v2) {
426 				if (!svc_reg(tcptransp, RPCPROG_MNT, RPCMNT_VER3,
427 				    mntsrv, tcpconf))
428 					syslog(LOG_WARNING, "can't register TCP RPCMNT_VER3 service");
429 				else
430 					xcreated++;
431 			}
432 		} else
433 			syslog(LOG_WARNING, "can't create TCP service");
434 
435 	}
436 	if (have_v6 && udp6sock != -1 && udp6conf != NULL) {
437 		bindresvport(udp6sock, NULL);
438 		udp6transp = svc_dg_create(udp6sock, 0, 0);
439 		if (udp6transp != NULL) {
440 			if (!svc_reg(udp6transp, RPCPROG_MNT, RPCMNT_VER1,
441 			    mntsrv, udp6conf))
442 				syslog(LOG_WARNING, "can't register UDP6 RPCMNT_VER1 service");
443 			else
444 				xcreated++;
445 			if (!force_v2) {
446 				if (!svc_reg(udp6transp, RPCPROG_MNT, RPCMNT_VER3,
447 				    mntsrv, udp6conf))
448 					syslog(LOG_WARNING, "can't register UDP6 RPCMNT_VER3 service");
449 				else
450 					xcreated++;
451 			}
452 		} else
453 			syslog(LOG_WARNING, "can't create UDP6 service");
454 
455 	}
456 	if (have_v6 && tcp6sock != -1 && tcp6conf != NULL) {
457 		bindresvport(tcp6sock, NULL);
458 		listen(tcp6sock, SOMAXCONN);
459 		tcp6transp = svc_vc_create(tcp6sock, 0, 0);
460 		if (tcp6transp != NULL) {
461 			if (!svc_reg(tcp6transp, RPCPROG_MNT, RPCMNT_VER1,
462 			    mntsrv, tcp6conf))
463 				syslog(LOG_WARNING, "can't register TCP6 RPCMNT_VER1 service");
464 			else
465 				xcreated++;
466 			if (!force_v2) {
467 				if (!svc_reg(tcp6transp, RPCPROG_MNT, RPCMNT_VER3,
468 				    mntsrv, tcp6conf))
469 					syslog(LOG_WARNING, "can't register TCP6 RPCMNT_VER3 service");
470 					else
471 						xcreated++;
472 				}
473 		} else
474 			syslog(LOG_WARNING, "can't create TCP6 service");
475 
476 	}
477 	if (xcreated == 0) {
478 		syslog(LOG_ERR, "could not create any services");
479 		exit(1);
480 	}
481 
482 	/* Expand svc_run() here so that we can call get_exportlist(). */
483 	for (;;) {
484 		if (got_sighup) {
485 			get_exportlist();
486 			got_sighup = 0;
487 		}
488 		readfds = svc_fdset;
489 		switch (select(svc_maxfd + 1, &readfds, NULL, NULL, NULL)) {
490 		case -1:
491 			if (errno == EINTR)
492                                 continue;
493 			syslog(LOG_ERR, "mountd died: select: %m");
494 			exit(1);
495 		case 0:
496 			continue;
497 		default:
498 			svc_getreqset(&readfds);
499 		}
500 	}
501 }
502 
503 static void
504 usage()
505 {
506 	fprintf(stderr,
507 		"usage: mountd [-2] [-d] [-l] [-n] [-r] [export_file]\n");
508 	exit(1);
509 }
510 
511 /*
512  * The mount rpc service
513  */
514 void
515 mntsrv(rqstp, transp)
516 	struct svc_req *rqstp;
517 	SVCXPRT *transp;
518 {
519 	struct exportlist *ep;
520 	struct dirlist *dp;
521 	struct fhreturn fhr;
522 	struct stat stb;
523 	struct statfs fsb;
524 	struct addrinfo *ai;
525 	char host[NI_MAXHOST], numerichost[NI_MAXHOST];
526 	int lookup_failed = 1;
527 	struct sockaddr *saddr;
528 	u_short sport;
529 	char rpcpath[RPCMNT_PATHLEN + 1], dirpath[MAXPATHLEN];
530 	int bad = 0, defset, hostset;
531 	sigset_t sighup_mask;
532 
533 	sigemptyset(&sighup_mask);
534 	sigaddset(&sighup_mask, SIGHUP);
535 	saddr = svc_getrpccaller(transp)->buf;
536 	switch (saddr->sa_family) {
537 	case AF_INET6:
538 		sport = ntohs(((struct sockaddr_in6 *)saddr)->sin6_port);
539 		break;
540 	case AF_INET:
541 		sport = ntohs(((struct sockaddr_in *)saddr)->sin_port);
542 		break;
543 	default:
544 		syslog(LOG_ERR, "request from unknown address family");
545 		return;
546 	}
547 	lookup_failed = getnameinfo(saddr, saddr->sa_len, host, sizeof host,
548 	    NULL, 0, 0);
549 	getnameinfo(saddr, saddr->sa_len, numerichost,
550 	    sizeof numerichost, NULL, 0, NI_NUMERICHOST);
551 	ai = NULL;
552 	switch (rqstp->rq_proc) {
553 	case NULLPROC:
554 		if (!svc_sendreply(transp, xdr_void, (caddr_t)NULL))
555 			syslog(LOG_ERR, "can't send reply");
556 		return;
557 	case RPCMNT_MOUNT:
558 		if (sport >= IPPORT_RESERVED && resvport_only) {
559 			syslog(LOG_NOTICE,
560 			    "mount request from %s from unprivileged port",
561 			    numerichost);
562 			svcerr_weakauth(transp);
563 			return;
564 		}
565 		if (!svc_getargs(transp, xdr_dir, rpcpath)) {
566 			syslog(LOG_NOTICE, "undecodable mount request from %s",
567 			    numerichost);
568 			svcerr_decode(transp);
569 			return;
570 		}
571 
572 		/*
573 		 * Get the real pathname and make sure it is a directory
574 		 * or a regular file if the -r option was specified
575 		 * and it exists.
576 		 */
577 		if (realpath(rpcpath, dirpath) == NULL ||
578 		    stat(dirpath, &stb) < 0 ||
579 		    (!S_ISDIR(stb.st_mode) &&
580 		    (dir_only || !S_ISREG(stb.st_mode))) ||
581 		    statfs(dirpath, &fsb) < 0) {
582 			chdir("/");	/* Just in case realpath doesn't */
583 			syslog(LOG_NOTICE,
584 			    "mount request from %s for non existent path %s",
585 			    numerichost, dirpath);
586 			if (debug)
587 				warnx("stat failed on %s", dirpath);
588 			bad = ENOENT;	/* We will send error reply later */
589 		}
590 
591 		/* Check in the exports list */
592 		sigprocmask(SIG_BLOCK, &sighup_mask, NULL);
593 		ep = ex_search(&fsb.f_fsid);
594 		hostset = defset = 0;
595 		if (ep && (chk_host(ep->ex_defdir, saddr, &defset, &hostset) ||
596 		    ((dp = dirp_search(ep->ex_dirl, dirpath)) &&
597 		      chk_host(dp, saddr, &defset, &hostset)) ||
598 		    (defset && scan_tree(ep->ex_defdir, saddr) == 0 &&
599 		     scan_tree(ep->ex_dirl, saddr) == 0))) {
600 			if (bad) {
601 				if (!svc_sendreply(transp, xdr_long,
602 				    (caddr_t)&bad))
603 					syslog(LOG_ERR, "can't send reply");
604 				sigprocmask(SIG_UNBLOCK, &sighup_mask, NULL);
605 				return;
606 			}
607 			if (hostset & DP_HOSTSET)
608 				fhr.fhr_flag = hostset;
609 			else
610 				fhr.fhr_flag = defset;
611 			fhr.fhr_vers = rqstp->rq_vers;
612 			/* Get the file handle */
613 			memset(&fhr.fhr_fh, 0, sizeof(nfsfh_t));
614 			if (getfh(dirpath, (fhandle_t *)&fhr.fhr_fh) < 0) {
615 				bad = errno;
616 				syslog(LOG_ERR, "can't get fh for %s", dirpath);
617 				if (!svc_sendreply(transp, xdr_long,
618 				    (caddr_t)&bad))
619 					syslog(LOG_ERR, "can't send reply");
620 				sigprocmask(SIG_UNBLOCK, &sighup_mask, NULL);
621 				return;
622 			}
623 			if (!svc_sendreply(transp, xdr_fhs, (caddr_t)&fhr))
624 				syslog(LOG_ERR, "can't send reply");
625 			if (!lookup_failed)
626 				add_mlist(host, dirpath);
627 			else
628 				add_mlist(numerichost, dirpath);
629 			if (debug)
630 				warnx("mount successful");
631 			if (log)
632 				syslog(LOG_NOTICE,
633 				    "mount request succeeded from %s for %s",
634 				    numerichost, dirpath);
635 		} else {
636 			bad = EACCES;
637 			syslog(LOG_NOTICE,
638 			    "mount request denied from %s for %s",
639 			    numerichost, dirpath);
640 		}
641 
642 		if (bad && !svc_sendreply(transp, xdr_long, (caddr_t)&bad))
643 			syslog(LOG_ERR, "can't send reply");
644 		sigprocmask(SIG_UNBLOCK, &sighup_mask, NULL);
645 		return;
646 	case RPCMNT_DUMP:
647 		if (!svc_sendreply(transp, xdr_mlist, (caddr_t)NULL))
648 			syslog(LOG_ERR, "can't send reply");
649 		else if (log)
650 			syslog(LOG_NOTICE,
651 			    "dump request succeeded from %s",
652 			    numerichost);
653 		return;
654 	case RPCMNT_UMOUNT:
655 		if (sport >= IPPORT_RESERVED && resvport_only) {
656 			syslog(LOG_NOTICE,
657 			    "umount request from %s from unprivileged port",
658 			    numerichost);
659 			svcerr_weakauth(transp);
660 			return;
661 		}
662 		if (!svc_getargs(transp, xdr_dir, rpcpath)) {
663 			syslog(LOG_NOTICE, "undecodable umount request from %s",
664 			    numerichost);
665 			svcerr_decode(transp);
666 			return;
667 		}
668 		if (realpath(rpcpath, dirpath) == NULL) {
669 			syslog(LOG_NOTICE, "umount request from %s "
670 			    "for non existent path %s",
671 			    numerichost, dirpath);
672 		}
673 		if (!svc_sendreply(transp, xdr_void, (caddr_t)NULL))
674 			syslog(LOG_ERR, "can't send reply");
675 		if (!lookup_failed)
676 			del_mlist(host, dirpath);
677 		del_mlist(numerichost, dirpath);
678 		if (log)
679 			syslog(LOG_NOTICE,
680 			    "umount request succeeded from %s for %s",
681 			    numerichost, dirpath);
682 		return;
683 	case RPCMNT_UMNTALL:
684 		if (sport >= IPPORT_RESERVED && resvport_only) {
685 			syslog(LOG_NOTICE,
686 			    "umountall request from %s from unprivileged port",
687 			    numerichost);
688 			svcerr_weakauth(transp);
689 			return;
690 		}
691 		if (!svc_sendreply(transp, xdr_void, (caddr_t)NULL))
692 			syslog(LOG_ERR, "can't send reply");
693 		if (!lookup_failed)
694 			del_mlist(host, NULL);
695 		del_mlist(numerichost, NULL);
696 		if (log)
697 			syslog(LOG_NOTICE,
698 			    "umountall request succeeded from %s",
699 			    numerichost);
700 		return;
701 	case RPCMNT_EXPORT:
702 		if (!svc_sendreply(transp, xdr_explist, (caddr_t)NULL))
703 			syslog(LOG_ERR, "can't send reply");
704 		if (log)
705 			syslog(LOG_NOTICE,
706 			    "export request succeeded from %s",
707 			    numerichost);
708 		return;
709 	default:
710 		svcerr_noproc(transp);
711 		return;
712 	}
713 }
714 
715 /*
716  * Xdr conversion for a dirpath string
717  */
718 int
719 xdr_dir(xdrsp, dirp)
720 	XDR *xdrsp;
721 	char *dirp;
722 {
723 	return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN));
724 }
725 
726 /*
727  * Xdr routine to generate file handle reply
728  */
729 int
730 xdr_fhs(xdrsp, cp)
731 	XDR *xdrsp;
732 	caddr_t cp;
733 {
734 	register struct fhreturn *fhrp = (struct fhreturn *)cp;
735 	u_long ok = 0, len, auth;
736 
737 	if (!xdr_long(xdrsp, &ok))
738 		return (0);
739 	switch (fhrp->fhr_vers) {
740 	case 1:
741 		return (xdr_opaque(xdrsp, (caddr_t)&fhrp->fhr_fh, NFSX_V2FH));
742 	case 3:
743 		len = NFSX_V3FH;
744 		if (!xdr_long(xdrsp, &len))
745 			return (0);
746 		if (!xdr_opaque(xdrsp, (caddr_t)&fhrp->fhr_fh, len))
747 			return (0);
748 		if (fhrp->fhr_flag & DP_KERB)
749 			auth = RPCAUTH_KERB4;
750 		else
751 			auth = RPCAUTH_UNIX;
752 		len = 1;
753 		if (!xdr_long(xdrsp, &len))
754 			return (0);
755 		return (xdr_long(xdrsp, &auth));
756 	};
757 	return (0);
758 }
759 
760 int
761 xdr_mlist(xdrsp, cp)
762 	XDR *xdrsp;
763 	caddr_t cp;
764 {
765 	struct mountlist *mlp;
766 	int true = 1;
767 	int false = 0;
768 	char *strp;
769 
770 	mlp = mlhead;
771 	while (mlp) {
772 		if (!xdr_bool(xdrsp, &true))
773 			return (0);
774 		strp = &mlp->ml_host[0];
775 		if (!xdr_string(xdrsp, &strp, RPCMNT_NAMELEN))
776 			return (0);
777 		strp = &mlp->ml_dirp[0];
778 		if (!xdr_string(xdrsp, &strp, RPCMNT_PATHLEN))
779 			return (0);
780 		mlp = mlp->ml_next;
781 	}
782 	if (!xdr_bool(xdrsp, &false))
783 		return (0);
784 	return (1);
785 }
786 
787 /*
788  * Xdr conversion for export list
789  */
790 int
791 xdr_explist(xdrsp, cp)
792 	XDR *xdrsp;
793 	caddr_t cp;
794 {
795 	struct exportlist *ep;
796 	int false = 0;
797 	int putdef;
798 	sigset_t sighup_mask;
799 
800 	sigemptyset(&sighup_mask);
801 	sigaddset(&sighup_mask, SIGHUP);
802 	sigprocmask(SIG_BLOCK, &sighup_mask, NULL);
803 	ep = exphead;
804 	while (ep) {
805 		putdef = 0;
806 		if (put_exlist(ep->ex_dirl, xdrsp, ep->ex_defdir, &putdef))
807 			goto errout;
808 		if (ep->ex_defdir && putdef == 0 &&
809 			put_exlist(ep->ex_defdir, xdrsp, (struct dirlist *)NULL,
810 			&putdef))
811 			goto errout;
812 		ep = ep->ex_next;
813 	}
814 	sigprocmask(SIG_UNBLOCK, &sighup_mask, NULL);
815 	if (!xdr_bool(xdrsp, &false))
816 		return (0);
817 	return (1);
818 errout:
819 	sigprocmask(SIG_UNBLOCK, &sighup_mask, NULL);
820 	return (0);
821 }
822 
823 /*
824  * Called from xdr_explist() to traverse the tree and export the
825  * directory paths.
826  */
827 int
828 put_exlist(dp, xdrsp, adp, putdefp)
829 	struct dirlist *dp;
830 	XDR *xdrsp;
831 	struct dirlist *adp;
832 	int *putdefp;
833 {
834 	struct grouplist *grp;
835 	struct hostlist *hp;
836 	int true = 1;
837 	int false = 0;
838 	int gotalldir = 0;
839 	char *strp;
840 
841 	if (dp) {
842 		if (put_exlist(dp->dp_left, xdrsp, adp, putdefp))
843 			return (1);
844 		if (!xdr_bool(xdrsp, &true))
845 			return (1);
846 		strp = dp->dp_dirp;
847 		if (!xdr_string(xdrsp, &strp, RPCMNT_PATHLEN))
848 			return (1);
849 		if (adp && !strcmp(dp->dp_dirp, adp->dp_dirp)) {
850 			gotalldir = 1;
851 			*putdefp = 1;
852 		}
853 		if ((dp->dp_flag & DP_DEFSET) == 0 &&
854 		    (gotalldir == 0 || (adp->dp_flag & DP_DEFSET) == 0)) {
855 			hp = dp->dp_hosts;
856 			while (hp) {
857 				grp = hp->ht_grp;
858 				if (grp->gr_type == GT_HOST) {
859 					if (!xdr_bool(xdrsp, &true))
860 						return (1);
861 					strp = grp->gr_ptr.gt_addrinfo->ai_canonname;
862 					if (!xdr_string(xdrsp, &strp,
863 					    RPCMNT_NAMELEN))
864 						return (1);
865 				} else if (grp->gr_type == GT_NET) {
866 					if (!xdr_bool(xdrsp, &true))
867 						return (1);
868 					strp = grp->gr_ptr.gt_net.nt_name;
869 					if (!xdr_string(xdrsp, &strp,
870 					    RPCMNT_NAMELEN))
871 						return (1);
872 				}
873 				hp = hp->ht_next;
874 				if (gotalldir && hp == (struct hostlist *)NULL) {
875 					hp = adp->dp_hosts;
876 					gotalldir = 0;
877 				}
878 			}
879 		}
880 		if (!xdr_bool(xdrsp, &false))
881 			return (1);
882 		if (put_exlist(dp->dp_right, xdrsp, adp, putdefp))
883 			return (1);
884 	}
885 	return (0);
886 }
887 
888 #define LINESIZ	10240
889 char line[LINESIZ];
890 FILE *exp_file;
891 
892 /*
893  * Get the export list
894  */
895 void
896 get_exportlist()
897 {
898 	struct exportlist *ep, *ep2;
899 	struct grouplist *grp, *tgrp;
900 	struct exportlist **epp;
901 	struct dirlist *dirhead;
902 	struct statfs fsb, *fsp;
903 	struct xucred anon;
904 	char *cp, *endcp, *dirp, *hst, *usr, *dom, savedc;
905 	int len, has_host, exflags, got_nondir, dirplen, num, i, netgrp;
906 
907 	dirp = NULL;
908 	dirplen = 0;
909 
910 	/*
911 	 * First, get rid of the old list
912 	 */
913 	ep = exphead;
914 	while (ep) {
915 		ep2 = ep;
916 		ep = ep->ex_next;
917 		free_exp(ep2);
918 	}
919 	exphead = (struct exportlist *)NULL;
920 
921 	grp = grphead;
922 	while (grp) {
923 		tgrp = grp;
924 		grp = grp->gr_next;
925 		free_grp(tgrp);
926 	}
927 	grphead = (struct grouplist *)NULL;
928 
929 	/*
930 	 * And delete exports that are in the kernel for all local
931 	 * file systems.
932 	 * XXX: Should know how to handle all local exportable file systems
933 	 *      instead of just "ufs".
934 	 */
935 	num = getmntinfo(&fsp, MNT_NOWAIT);
936 	for (i = 0; i < num; i++) {
937 		union {
938 			struct ufs_args ua;
939 			struct iso_args ia;
940 			struct msdosfs_args da;
941 			struct ntfs_args na;
942 		} targs;
943 
944 		if (!strcmp(fsp->f_fstypename, "ufs") ||
945 		    !strcmp(fsp->f_fstypename, "msdosfs") ||
946 		    !strcmp(fsp->f_fstypename, "ntfs") ||
947 		    !strcmp(fsp->f_fstypename, "cd9660")) {
948 			targs.ua.fspec = NULL;
949 			targs.ua.export.ex_flags = MNT_DELEXPORT;
950 			if (mount(fsp->f_fstypename, fsp->f_mntonname,
951 			    fsp->f_flags | MNT_UPDATE, (caddr_t)&targs) < 0 &&
952 			    errno != ENOENT)
953 				syslog(LOG_ERR,
954 				    "can't delete exports for %s: %m",
955 				    fsp->f_mntonname);
956 		}
957 		fsp++;
958 	}
959 
960 	/*
961 	 * Read in the exports file and build the list, calling
962 	 * mount() as we go along to push the export rules into the kernel.
963 	 */
964 	if ((exp_file = fopen(exname, "r")) == NULL) {
965 		syslog(LOG_ERR, "can't open %s", exname);
966 		exit(2);
967 	}
968 	dirhead = (struct dirlist *)NULL;
969 	while (get_line()) {
970 		if (debug)
971 			warnx("got line %s", line);
972 		cp = line;
973 		nextfield(&cp, &endcp);
974 		if (*cp == '#')
975 			goto nextline;
976 
977 		/*
978 		 * Set defaults.
979 		 */
980 		has_host = FALSE;
981 		anon = def_anon;
982 		exflags = MNT_EXPORTED;
983 		got_nondir = 0;
984 		opt_flags = 0;
985 		ep = (struct exportlist *)NULL;
986 
987 		/*
988 		 * Create new exports list entry
989 		 */
990 		len = endcp-cp;
991 		tgrp = grp = get_grp();
992 		while (len > 0) {
993 			if (len > RPCMNT_NAMELEN) {
994 			    getexp_err(ep, tgrp);
995 			    goto nextline;
996 			}
997 			if (*cp == '-') {
998 			    if (ep == (struct exportlist *)NULL) {
999 				getexp_err(ep, tgrp);
1000 				goto nextline;
1001 			    }
1002 			    if (debug)
1003 				warnx("doing opt %s", cp);
1004 			    got_nondir = 1;
1005 			    if (do_opt(&cp, &endcp, ep, grp, &has_host,
1006 				&exflags, &anon)) {
1007 				getexp_err(ep, tgrp);
1008 				goto nextline;
1009 			    }
1010 			} else if (*cp == '/') {
1011 			    savedc = *endcp;
1012 			    *endcp = '\0';
1013 			    if (check_dirpath(cp) &&
1014 				statfs(cp, &fsb) >= 0) {
1015 				if (got_nondir) {
1016 				    syslog(LOG_ERR, "dirs must be first");
1017 				    getexp_err(ep, tgrp);
1018 				    goto nextline;
1019 				}
1020 				if (ep) {
1021 				    if (ep->ex_fs.val[0] != fsb.f_fsid.val[0] ||
1022 					ep->ex_fs.val[1] != fsb.f_fsid.val[1]) {
1023 					getexp_err(ep, tgrp);
1024 					goto nextline;
1025 				    }
1026 				} else {
1027 				    /*
1028 				     * See if this directory is already
1029 				     * in the list.
1030 				     */
1031 				    ep = ex_search(&fsb.f_fsid);
1032 				    if (ep == (struct exportlist *)NULL) {
1033 					ep = get_exp();
1034 					ep->ex_fs = fsb.f_fsid;
1035 					ep->ex_fsdir = (char *)
1036 					    malloc(strlen(fsb.f_mntonname) + 1);
1037 					if (ep->ex_fsdir)
1038 					    strcpy(ep->ex_fsdir,
1039 						fsb.f_mntonname);
1040 					else
1041 					    out_of_mem();
1042 					if (debug)
1043 						warnx("making new ep fs=0x%x,0x%x",
1044 						    fsb.f_fsid.val[0],
1045 						    fsb.f_fsid.val[1]);
1046 				    } else if (debug)
1047 					warnx("found ep fs=0x%x,0x%x",
1048 					    fsb.f_fsid.val[0],
1049 					    fsb.f_fsid.val[1]);
1050 				}
1051 
1052 				/*
1053 				 * Add dirpath to export mount point.
1054 				 */
1055 				dirp = add_expdir(&dirhead, cp, len);
1056 				dirplen = len;
1057 			    } else {
1058 				getexp_err(ep, tgrp);
1059 				goto nextline;
1060 			    }
1061 			    *endcp = savedc;
1062 			} else {
1063 			    savedc = *endcp;
1064 			    *endcp = '\0';
1065 			    got_nondir = 1;
1066 			    if (ep == (struct exportlist *)NULL) {
1067 				getexp_err(ep, tgrp);
1068 				goto nextline;
1069 			    }
1070 
1071 			    /*
1072 			     * Get the host or netgroup.
1073 			     */
1074 			    setnetgrent(cp);
1075 			    netgrp = getnetgrent(&hst, &usr, &dom);
1076 			    do {
1077 				if (has_host) {
1078 				    grp->gr_next = get_grp();
1079 				    grp = grp->gr_next;
1080 				}
1081 				if (netgrp) {
1082 				    if (hst == 0) {
1083 					syslog(LOG_ERR,
1084 				"null hostname in netgroup %s, skipping", cp);
1085 					grp->gr_type = GT_IGNORE;
1086 				    } else if (get_host(hst, grp, tgrp)) {
1087 					syslog(LOG_ERR,
1088 			"bad host %s in netgroup %s, skipping", hst, cp);
1089 					grp->gr_type = GT_IGNORE;
1090 				    }
1091 				} else if (get_host(cp, grp, tgrp)) {
1092 				    syslog(LOG_ERR, "bad host %s, skipping", cp);
1093 				    grp->gr_type = GT_IGNORE;
1094 				}
1095 				has_host = TRUE;
1096 			    } while (netgrp && getnetgrent(&hst, &usr, &dom));
1097 			    endnetgrent();
1098 			    *endcp = savedc;
1099 			}
1100 			cp = endcp;
1101 			nextfield(&cp, &endcp);
1102 			len = endcp - cp;
1103 		}
1104 		if (check_options(dirhead)) {
1105 			getexp_err(ep, tgrp);
1106 			goto nextline;
1107 		}
1108 		if (!has_host) {
1109 			grp->gr_type = GT_DEFAULT;
1110 			if (debug)
1111 				warnx("adding a default entry");
1112 
1113 		/*
1114 		 * Don't allow a network export coincide with a list of
1115 		 * host(s) on the same line.
1116 		 */
1117 		} else if ((opt_flags & OP_NET) && tgrp->gr_next) {
1118 			syslog(LOG_ERR, "network/host conflict");
1119 			getexp_err(ep, tgrp);
1120 			goto nextline;
1121 
1122 		/*
1123 		 * If an export list was specified on this line, make sure
1124 		 * that we have at least one valid entry, otherwise skip it.
1125 		 */
1126 		} else {
1127 			grp = tgrp;
1128 			while (grp && grp->gr_type == GT_IGNORE)
1129 				grp = grp->gr_next;
1130 			if (! grp) {
1131 			    getexp_err(ep, tgrp);
1132 			    goto nextline;
1133 			}
1134 		}
1135 
1136 		/*
1137 		 * Loop through hosts, pushing the exports into the kernel.
1138 		 * After loop, tgrp points to the start of the list and
1139 		 * grp points to the last entry in the list.
1140 		 */
1141 		grp = tgrp;
1142 		do {
1143 			if (do_mount(ep, grp, exflags, &anon, dirp, dirplen,
1144 			    &fsb)) {
1145 				getexp_err(ep, tgrp);
1146 				goto nextline;
1147 			}
1148 		} while (grp->gr_next && (grp = grp->gr_next));
1149 
1150 		/*
1151 		 * Success. Update the data structures.
1152 		 */
1153 		if (has_host) {
1154 			hang_dirp(dirhead, tgrp, ep, opt_flags);
1155 			grp->gr_next = grphead;
1156 			grphead = tgrp;
1157 		} else {
1158 			hang_dirp(dirhead, (struct grouplist *)NULL, ep,
1159 				opt_flags);
1160 			free_grp(grp);
1161 		}
1162 		dirhead = (struct dirlist *)NULL;
1163 		if ((ep->ex_flag & EX_LINKED) == 0) {
1164 			ep2 = exphead;
1165 			epp = &exphead;
1166 
1167 			/*
1168 			 * Insert in the list in alphabetical order.
1169 			 */
1170 			while (ep2 && strcmp(ep2->ex_fsdir, ep->ex_fsdir) < 0) {
1171 				epp = &ep2->ex_next;
1172 				ep2 = ep2->ex_next;
1173 			}
1174 			if (ep2)
1175 				ep->ex_next = ep2;
1176 			*epp = ep;
1177 			ep->ex_flag |= EX_LINKED;
1178 		}
1179 nextline:
1180 		if (dirhead) {
1181 			free_dir(dirhead);
1182 			dirhead = (struct dirlist *)NULL;
1183 		}
1184 	}
1185 	fclose(exp_file);
1186 }
1187 
1188 /*
1189  * Allocate an export list element
1190  */
1191 struct exportlist *
1192 get_exp()
1193 {
1194 	struct exportlist *ep;
1195 
1196 	ep = (struct exportlist *)malloc(sizeof (struct exportlist));
1197 	if (ep == (struct exportlist *)NULL)
1198 		out_of_mem();
1199 	memset(ep, 0, sizeof(struct exportlist));
1200 	return (ep);
1201 }
1202 
1203 /*
1204  * Allocate a group list element
1205  */
1206 struct grouplist *
1207 get_grp()
1208 {
1209 	struct grouplist *gp;
1210 
1211 	gp = (struct grouplist *)malloc(sizeof (struct grouplist));
1212 	if (gp == (struct grouplist *)NULL)
1213 		out_of_mem();
1214 	memset(gp, 0, sizeof(struct grouplist));
1215 	return (gp);
1216 }
1217 
1218 /*
1219  * Clean up upon an error in get_exportlist().
1220  */
1221 void
1222 getexp_err(ep, grp)
1223 	struct exportlist *ep;
1224 	struct grouplist *grp;
1225 {
1226 	struct grouplist *tgrp;
1227 
1228 	syslog(LOG_ERR, "bad exports list line %s", line);
1229 	if (ep && (ep->ex_flag & EX_LINKED) == 0)
1230 		free_exp(ep);
1231 	while (grp) {
1232 		tgrp = grp;
1233 		grp = grp->gr_next;
1234 		free_grp(tgrp);
1235 	}
1236 }
1237 
1238 /*
1239  * Search the export list for a matching fs.
1240  */
1241 struct exportlist *
1242 ex_search(fsid)
1243 	fsid_t *fsid;
1244 {
1245 	struct exportlist *ep;
1246 
1247 	ep = exphead;
1248 	while (ep) {
1249 		if (ep->ex_fs.val[0] == fsid->val[0] &&
1250 		    ep->ex_fs.val[1] == fsid->val[1])
1251 			return (ep);
1252 		ep = ep->ex_next;
1253 	}
1254 	return (ep);
1255 }
1256 
1257 /*
1258  * Add a directory path to the list.
1259  */
1260 char *
1261 add_expdir(dpp, cp, len)
1262 	struct dirlist **dpp;
1263 	char *cp;
1264 	int len;
1265 {
1266 	struct dirlist *dp;
1267 
1268 	dp = (struct dirlist *)malloc(sizeof (struct dirlist) + len);
1269 	if (dp == (struct dirlist *)NULL)
1270 		out_of_mem();
1271 	dp->dp_left = *dpp;
1272 	dp->dp_right = (struct dirlist *)NULL;
1273 	dp->dp_flag = 0;
1274 	dp->dp_hosts = (struct hostlist *)NULL;
1275 	strcpy(dp->dp_dirp, cp);
1276 	*dpp = dp;
1277 	return (dp->dp_dirp);
1278 }
1279 
1280 /*
1281  * Hang the dir list element off the dirpath binary tree as required
1282  * and update the entry for host.
1283  */
1284 void
1285 hang_dirp(dp, grp, ep, flags)
1286 	struct dirlist *dp;
1287 	struct grouplist *grp;
1288 	struct exportlist *ep;
1289 	int flags;
1290 {
1291 	struct hostlist *hp;
1292 	struct dirlist *dp2;
1293 
1294 	if (flags & OP_ALLDIRS) {
1295 		if (ep->ex_defdir)
1296 			free((caddr_t)dp);
1297 		else
1298 			ep->ex_defdir = dp;
1299 		if (grp == (struct grouplist *)NULL) {
1300 			ep->ex_defdir->dp_flag |= DP_DEFSET;
1301 			if (flags & OP_KERB)
1302 				ep->ex_defdir->dp_flag |= DP_KERB;
1303 		} else while (grp) {
1304 			hp = get_ht();
1305 			if (flags & OP_KERB)
1306 				hp->ht_flag |= DP_KERB;
1307 			hp->ht_grp = grp;
1308 			hp->ht_next = ep->ex_defdir->dp_hosts;
1309 			ep->ex_defdir->dp_hosts = hp;
1310 			grp = grp->gr_next;
1311 		}
1312 	} else {
1313 
1314 		/*
1315 		 * Loop through the directories adding them to the tree.
1316 		 */
1317 		while (dp) {
1318 			dp2 = dp->dp_left;
1319 			add_dlist(&ep->ex_dirl, dp, grp, flags);
1320 			dp = dp2;
1321 		}
1322 	}
1323 }
1324 
1325 /*
1326  * Traverse the binary tree either updating a node that is already there
1327  * for the new directory or adding the new node.
1328  */
1329 void
1330 add_dlist(dpp, newdp, grp, flags)
1331 	struct dirlist **dpp;
1332 	struct dirlist *newdp;
1333 	struct grouplist *grp;
1334 	int flags;
1335 {
1336 	struct dirlist *dp;
1337 	struct hostlist *hp;
1338 	int cmp;
1339 
1340 	dp = *dpp;
1341 	if (dp) {
1342 		cmp = strcmp(dp->dp_dirp, newdp->dp_dirp);
1343 		if (cmp > 0) {
1344 			add_dlist(&dp->dp_left, newdp, grp, flags);
1345 			return;
1346 		} else if (cmp < 0) {
1347 			add_dlist(&dp->dp_right, newdp, grp, flags);
1348 			return;
1349 		} else
1350 			free((caddr_t)newdp);
1351 	} else {
1352 		dp = newdp;
1353 		dp->dp_left = (struct dirlist *)NULL;
1354 		*dpp = dp;
1355 	}
1356 	if (grp) {
1357 
1358 		/*
1359 		 * Hang all of the host(s) off of the directory point.
1360 		 */
1361 		do {
1362 			hp = get_ht();
1363 			if (flags & OP_KERB)
1364 				hp->ht_flag |= DP_KERB;
1365 			hp->ht_grp = grp;
1366 			hp->ht_next = dp->dp_hosts;
1367 			dp->dp_hosts = hp;
1368 			grp = grp->gr_next;
1369 		} while (grp);
1370 	} else {
1371 		dp->dp_flag |= DP_DEFSET;
1372 		if (flags & OP_KERB)
1373 			dp->dp_flag |= DP_KERB;
1374 	}
1375 }
1376 
1377 /*
1378  * Search for a dirpath on the export point.
1379  */
1380 struct dirlist *
1381 dirp_search(dp, dirp)
1382 	struct dirlist *dp;
1383 	char *dirp;
1384 {
1385 	int cmp;
1386 
1387 	if (dp) {
1388 		cmp = strcmp(dp->dp_dirp, dirp);
1389 		if (cmp > 0)
1390 			return (dirp_search(dp->dp_left, dirp));
1391 		else if (cmp < 0)
1392 			return (dirp_search(dp->dp_right, dirp));
1393 		else
1394 			return (dp);
1395 	}
1396 	return (dp);
1397 }
1398 
1399 /*
1400  * Scan for a host match in a directory tree.
1401  */
1402 int
1403 chk_host(dp, saddr, defsetp, hostsetp)
1404 	struct dirlist *dp;
1405 	struct sockaddr *saddr;
1406 	int *defsetp;
1407 	int *hostsetp;
1408 {
1409 	struct hostlist *hp;
1410 	struct grouplist *grp;
1411 	struct addrinfo *ai;
1412 
1413 	if (dp) {
1414 		if (dp->dp_flag & DP_DEFSET)
1415 			*defsetp = dp->dp_flag;
1416 		hp = dp->dp_hosts;
1417 		while (hp) {
1418 			grp = hp->ht_grp;
1419 			switch (grp->gr_type) {
1420 			case GT_HOST:
1421 				ai = grp->gr_ptr.gt_addrinfo;
1422 				for (; ai; ai = ai->ai_next) {
1423 					if (!sacmp(ai->ai_addr, saddr, NULL)) {
1424 						*hostsetp =
1425 						    (hp->ht_flag | DP_HOSTSET);
1426 						return (1);
1427 					}
1428 				}
1429 				break;
1430 			case GT_NET:
1431 				if (!sacmp(saddr, (struct sockaddr *)
1432 				    &grp->gr_ptr.gt_net.nt_net,
1433 				    (struct sockaddr *)
1434 				    &grp->gr_ptr.gt_net.nt_mask)) {
1435 					*hostsetp = (hp->ht_flag | DP_HOSTSET);
1436 					return (1);
1437 				}
1438 				break;
1439 			}
1440 			hp = hp->ht_next;
1441 		}
1442 	}
1443 	return (0);
1444 }
1445 
1446 /*
1447  * Scan tree for a host that matches the address.
1448  */
1449 int
1450 scan_tree(dp, saddr)
1451 	struct dirlist *dp;
1452 	struct sockaddr *saddr;
1453 {
1454 	int defset, hostset;
1455 
1456 	if (dp) {
1457 		if (scan_tree(dp->dp_left, saddr))
1458 			return (1);
1459 		if (chk_host(dp, saddr, &defset, &hostset))
1460 			return (1);
1461 		if (scan_tree(dp->dp_right, saddr))
1462 			return (1);
1463 	}
1464 	return (0);
1465 }
1466 
1467 /*
1468  * Traverse the dirlist tree and free it up.
1469  */
1470 void
1471 free_dir(dp)
1472 	struct dirlist *dp;
1473 {
1474 
1475 	if (dp) {
1476 		free_dir(dp->dp_left);
1477 		free_dir(dp->dp_right);
1478 		free_host(dp->dp_hosts);
1479 		free((caddr_t)dp);
1480 	}
1481 }
1482 
1483 /*
1484  * Parse the option string and update fields.
1485  * Option arguments may either be -<option>=<value> or
1486  * -<option> <value>
1487  */
1488 int
1489 do_opt(cpp, endcpp, ep, grp, has_hostp, exflagsp, cr)
1490 	char **cpp, **endcpp;
1491 	struct exportlist *ep;
1492 	struct grouplist *grp;
1493 	int *has_hostp;
1494 	int *exflagsp;
1495 	struct xucred *cr;
1496 {
1497 	char *cpoptarg, *cpoptend;
1498 	char *cp, *endcp, *cpopt, savedc, savedc2;
1499 	int allflag, usedarg;
1500 
1501 	savedc2 = '\0';
1502 	cpopt = *cpp;
1503 	cpopt++;
1504 	cp = *endcpp;
1505 	savedc = *cp;
1506 	*cp = '\0';
1507 	while (cpopt && *cpopt) {
1508 		allflag = 1;
1509 		usedarg = -2;
1510 		if ((cpoptend = strchr(cpopt, ','))) {
1511 			*cpoptend++ = '\0';
1512 			if ((cpoptarg = strchr(cpopt, '=')))
1513 				*cpoptarg++ = '\0';
1514 		} else {
1515 			if ((cpoptarg = strchr(cpopt, '=')))
1516 				*cpoptarg++ = '\0';
1517 			else {
1518 				*cp = savedc;
1519 				nextfield(&cp, &endcp);
1520 				**endcpp = '\0';
1521 				if (endcp > cp && *cp != '-') {
1522 					cpoptarg = cp;
1523 					savedc2 = *endcp;
1524 					*endcp = '\0';
1525 					usedarg = 0;
1526 				}
1527 			}
1528 		}
1529 		if (!strcmp(cpopt, "ro") || !strcmp(cpopt, "o")) {
1530 			*exflagsp |= MNT_EXRDONLY;
1531 		} else if (cpoptarg && (!strcmp(cpopt, "maproot") ||
1532 		    !(allflag = strcmp(cpopt, "mapall")) ||
1533 		    !strcmp(cpopt, "root") || !strcmp(cpopt, "r"))) {
1534 			usedarg++;
1535 			parsecred(cpoptarg, cr);
1536 			if (allflag == 0) {
1537 				*exflagsp |= MNT_EXPORTANON;
1538 				opt_flags |= OP_MAPALL;
1539 			} else
1540 				opt_flags |= OP_MAPROOT;
1541 		} else if (!strcmp(cpopt, "kerb") || !strcmp(cpopt, "k")) {
1542 			*exflagsp |= MNT_EXKERB;
1543 			opt_flags |= OP_KERB;
1544 		} else if (cpoptarg && (!strcmp(cpopt, "mask") ||
1545 		    !strcmp(cpopt, "m"))) {
1546 			if (get_net(cpoptarg, &grp->gr_ptr.gt_net, 1)) {
1547 				syslog(LOG_ERR, "bad mask: %s", cpoptarg);
1548 				return (1);
1549 			}
1550 			usedarg++;
1551 			opt_flags |= OP_MASK;
1552 		} else if (cpoptarg && (!strcmp(cpopt, "network") ||
1553 			!strcmp(cpopt, "n"))) {
1554 			if (strchr(cpoptarg, '/') != NULL) {
1555 				if (debug)
1556 					fprintf(stderr, "setting OP_MASKLEN\n");
1557 				opt_flags |= OP_MASKLEN;
1558 			}
1559 			if (grp->gr_type != GT_NULL) {
1560 				syslog(LOG_ERR, "network/host conflict");
1561 				return (1);
1562 			} else if (get_net(cpoptarg, &grp->gr_ptr.gt_net, 0)) {
1563 				syslog(LOG_ERR, "bad net: %s", cpoptarg);
1564 				return (1);
1565 			}
1566 			grp->gr_type = GT_NET;
1567 			*has_hostp = 1;
1568 			usedarg++;
1569 			opt_flags |= OP_NET;
1570 		} else if (!strcmp(cpopt, "alldirs")) {
1571 			opt_flags |= OP_ALLDIRS;
1572 		} else if (!strcmp(cpopt, "public")) {
1573 			*exflagsp |= MNT_EXPUBLIC;
1574 		} else if (!strcmp(cpopt, "webnfs")) {
1575 			*exflagsp |= (MNT_EXPUBLIC|MNT_EXRDONLY|MNT_EXPORTANON);
1576 			opt_flags |= OP_MAPALL;
1577 		} else if (cpoptarg && !strcmp(cpopt, "index")) {
1578 			ep->ex_indexfile = strdup(cpoptarg);
1579 		} else {
1580 			syslog(LOG_ERR, "bad opt %s", cpopt);
1581 			return (1);
1582 		}
1583 		if (usedarg >= 0) {
1584 			*endcp = savedc2;
1585 			**endcpp = savedc;
1586 			if (usedarg > 0) {
1587 				*cpp = cp;
1588 				*endcpp = endcp;
1589 			}
1590 			return (0);
1591 		}
1592 		cpopt = cpoptend;
1593 	}
1594 	**endcpp = savedc;
1595 	return (0);
1596 }
1597 
1598 /*
1599  * Translate a character string to the corresponding list of network
1600  * addresses for a hostname.
1601  */
1602 int
1603 get_host(cp, grp, tgrp)
1604 	char *cp;
1605 	struct grouplist *grp;
1606 	struct grouplist *tgrp;
1607 {
1608 	struct grouplist *checkgrp;
1609 	struct addrinfo *ai, *tai, hints;
1610 	int ecode;
1611 	char host[NI_MAXHOST];
1612 
1613 	if (grp->gr_type != GT_NULL) {
1614 		syslog(LOG_ERR, "Bad netgroup type for ip host %s", cp);
1615 		return (1);
1616 	}
1617 	memset(&hints, 0, sizeof hints);
1618 	hints.ai_flags = AI_CANONNAME;
1619 	hints.ai_protocol = IPPROTO_UDP;
1620 	ecode = getaddrinfo(cp, NULL, &hints, &ai);
1621 	if (ecode != 0) {
1622 		syslog(LOG_ERR,"can't get address info for host %s", cp);
1623 		return 1;
1624 	}
1625 	grp->gr_ptr.gt_addrinfo = ai;
1626 	while (ai != NULL) {
1627 		if (ai->ai_canonname == NULL) {
1628 			if (getnameinfo(ai->ai_addr, ai->ai_addrlen, host,
1629 			    sizeof host, NULL, 0, ninumeric) != 0)
1630 				strlcpy(host, "?", sizeof(host));
1631 			ai->ai_canonname = strdup(host);
1632 			ai->ai_flags |= AI_CANONNAME;
1633 		}
1634 		if (debug)
1635 			fprintf(stderr, "got host %s\n", ai->ai_canonname);
1636 		/*
1637 		 * Sanity check: make sure we don't already have an entry
1638 		 * for this host in the grouplist.
1639 		 */
1640 		for (checkgrp = tgrp; checkgrp != NULL;
1641 		    checkgrp = checkgrp->gr_next) {
1642 			if (checkgrp->gr_type != GT_HOST)
1643 				continue;
1644 			for (tai = checkgrp->gr_ptr.gt_addrinfo; tai != NULL;
1645 			    tai = tai->ai_next) {
1646 				if (sacmp(tai->ai_addr, ai->ai_addr, NULL) != 0)
1647 					continue;
1648 				if (debug)
1649 					fprintf(stderr,
1650 					    "ignoring duplicate host %s\n",
1651 					    ai->ai_canonname);
1652 				grp->gr_type = GT_IGNORE;
1653 				return (0);
1654 			}
1655 		}
1656 		ai = ai->ai_next;
1657 	}
1658 	grp->gr_type = GT_HOST;
1659 	return (0);
1660 }
1661 
1662 /*
1663  * Free up an exports list component
1664  */
1665 void
1666 free_exp(ep)
1667 	struct exportlist *ep;
1668 {
1669 
1670 	if (ep->ex_defdir) {
1671 		free_host(ep->ex_defdir->dp_hosts);
1672 		free((caddr_t)ep->ex_defdir);
1673 	}
1674 	if (ep->ex_fsdir)
1675 		free(ep->ex_fsdir);
1676 	if (ep->ex_indexfile)
1677 		free(ep->ex_indexfile);
1678 	free_dir(ep->ex_dirl);
1679 	free((caddr_t)ep);
1680 }
1681 
1682 /*
1683  * Free hosts.
1684  */
1685 void
1686 free_host(hp)
1687 	struct hostlist *hp;
1688 {
1689 	struct hostlist *hp2;
1690 
1691 	while (hp) {
1692 		hp2 = hp;
1693 		hp = hp->ht_next;
1694 		free((caddr_t)hp2);
1695 	}
1696 }
1697 
1698 struct hostlist *
1699 get_ht()
1700 {
1701 	struct hostlist *hp;
1702 
1703 	hp = (struct hostlist *)malloc(sizeof (struct hostlist));
1704 	if (hp == (struct hostlist *)NULL)
1705 		out_of_mem();
1706 	hp->ht_next = (struct hostlist *)NULL;
1707 	hp->ht_flag = 0;
1708 	return (hp);
1709 }
1710 
1711 /*
1712  * Out of memory, fatal
1713  */
1714 void
1715 out_of_mem()
1716 {
1717 
1718 	syslog(LOG_ERR, "out of memory");
1719 	exit(2);
1720 }
1721 
1722 /*
1723  * Do the mount syscall with the update flag to push the export info into
1724  * the kernel.
1725  */
1726 int
1727 do_mount(ep, grp, exflags, anoncrp, dirp, dirplen, fsb)
1728 	struct exportlist *ep;
1729 	struct grouplist *grp;
1730 	int exflags;
1731 	struct xucred *anoncrp;
1732 	char *dirp;
1733 	int dirplen;
1734 	struct statfs *fsb;
1735 {
1736 	struct statfs fsb1;
1737 	struct addrinfo *ai;
1738 	struct export_args *eap;
1739 	char *cp = NULL;
1740 	int done;
1741 	char savedc = '\0';
1742 	union {
1743 		struct ufs_args ua;
1744 		struct iso_args ia;
1745 		struct msdosfs_args da;
1746 		struct ntfs_args na;
1747 	} args;
1748 
1749 	bzero(&args, sizeof args);
1750 	/* XXX, we assume that all xx_args look like ufs_args. */
1751 	args.ua.fspec = 0;
1752 	eap = &args.ua.export;
1753 
1754 	eap->ex_flags = exflags;
1755 	eap->ex_anon = *anoncrp;
1756 	eap->ex_indexfile = ep->ex_indexfile;
1757 	if (grp->gr_type == GT_HOST)
1758 		ai = grp->gr_ptr.gt_addrinfo;
1759 	else
1760 		ai = NULL;
1761 	done = FALSE;
1762 	while (!done) {
1763 		switch (grp->gr_type) {
1764 		case GT_HOST:
1765 			if (ai->ai_addr->sa_family == AF_INET6 && have_v6 == 0)
1766 				goto skip;
1767 			eap->ex_addr = ai->ai_addr;
1768 			eap->ex_addrlen = ai->ai_addrlen;
1769 			eap->ex_masklen = 0;
1770 			break;
1771 		case GT_NET:
1772 			if (grp->gr_ptr.gt_net.nt_net.ss_family == AF_INET6 &&
1773 			    have_v6 == 0)
1774 				goto skip;
1775 			eap->ex_addr =
1776 			    (struct sockaddr *)&grp->gr_ptr.gt_net.nt_net;
1777 			eap->ex_addrlen = args.ua.export.ex_addr->sa_len;
1778 			eap->ex_mask =
1779 			    (struct sockaddr *)&grp->gr_ptr.gt_net.nt_mask;
1780 			eap->ex_masklen = args.ua.export.ex_mask->sa_len;
1781 			break;
1782 		case GT_DEFAULT:
1783 			eap->ex_addr = NULL;
1784 			eap->ex_addrlen = 0;
1785 			eap->ex_mask = NULL;
1786 			eap->ex_masklen = 0;
1787 			break;
1788 		case GT_IGNORE:
1789 			return(0);
1790 			break;
1791 		default:
1792 			syslog(LOG_ERR, "bad grouptype");
1793 			if (cp)
1794 				*cp = savedc;
1795 			return (1);
1796 		};
1797 
1798 		/*
1799 		 * XXX:
1800 		 * Maybe I should just use the fsb->f_mntonname path instead
1801 		 * of looping back up the dirp to the mount point??
1802 		 * Also, needs to know how to export all types of local
1803 		 * exportable file systems and not just "ufs".
1804 		 */
1805 		while (mount(fsb->f_fstypename, dirp,
1806 		    fsb->f_flags | MNT_UPDATE, (caddr_t)&args) < 0) {
1807 			if (cp)
1808 				*cp-- = savedc;
1809 			else
1810 				cp = dirp + dirplen - 1;
1811 			if (errno == EPERM) {
1812 				if (debug)
1813 					warnx("can't change attributes for %s",
1814 					    dirp);
1815 				syslog(LOG_ERR,
1816 				   "can't change attributes for %s", dirp);
1817 				return (1);
1818 			}
1819 			if (opt_flags & OP_ALLDIRS) {
1820 				syslog(LOG_ERR, "could not remount %s: %m",
1821 					dirp);
1822 				return (1);
1823 			}
1824 			/* back up over the last component */
1825 			while (*cp == '/' && cp > dirp)
1826 				cp--;
1827 			while (*(cp - 1) != '/' && cp > dirp)
1828 				cp--;
1829 			if (cp == dirp) {
1830 				if (debug)
1831 					warnx("mnt unsucc");
1832 				syslog(LOG_ERR, "can't export %s", dirp);
1833 				return (1);
1834 			}
1835 			savedc = *cp;
1836 			*cp = '\0';
1837 			/* Check that we're still on the same filesystem. */
1838 			if (statfs(dirp, &fsb1) != 0 || bcmp(&fsb1.f_fsid,
1839 			    &fsb->f_fsid, sizeof(fsb1.f_fsid)) != 0) {
1840 				*cp = savedc;
1841 				syslog(LOG_ERR, "can't export %s", dirp);
1842 				return (1);
1843 			}
1844 		}
1845 skip:
1846 		if (ai != NULL)
1847 			ai = ai->ai_next;
1848 		if (ai == NULL)
1849 			done = TRUE;
1850 	}
1851 	if (cp)
1852 		*cp = savedc;
1853 	return (0);
1854 }
1855 
1856 /*
1857  * Translate a net address.
1858  *
1859  * If `maskflg' is nonzero, then `cp' is a netmask, not a network address.
1860  */
1861 int
1862 get_net(cp, net, maskflg)
1863 	char *cp;
1864 	struct netmsk *net;
1865 	int maskflg;
1866 {
1867 	struct netent *np = NULL;
1868 	char *name, *p, *prefp;
1869 	struct sockaddr_in sin;
1870 	struct sockaddr *sa = NULL;
1871 	struct addrinfo hints, *ai = NULL;
1872 	char netname[NI_MAXHOST];
1873 	long preflen;
1874 
1875 	p = prefp = NULL;
1876 	if ((opt_flags & OP_MASKLEN) && !maskflg) {
1877 		p = strchr(cp, '/');
1878 		*p = '\0';
1879 		prefp = p + 1;
1880 	}
1881 
1882 	/*
1883 	 * Check for a numeric address first. We wish to avoid
1884 	 * possible DNS lookups in getnetbyname().
1885 	 */
1886 	if (isxdigit(*cp) || *cp == ':') {
1887 		memset(&hints, 0, sizeof hints);
1888 		/* Ensure the mask and the network have the same family. */
1889 		if (maskflg && (opt_flags & OP_NET))
1890 			hints.ai_family = net->nt_net.ss_family;
1891 		else if (!maskflg && (opt_flags & OP_HAVEMASK))
1892 			hints.ai_family = net->nt_mask.ss_family;
1893 		else
1894 			hints.ai_family = AF_UNSPEC;
1895 		hints.ai_flags = AI_NUMERICHOST;
1896 		if (getaddrinfo(cp, NULL, &hints, &ai) == 0)
1897 			sa = ai->ai_addr;
1898 		if (sa != NULL && ai->ai_family == AF_INET) {
1899 			/*
1900 			 * The address in `cp' is really a network address, so
1901 			 * use inet_network() to re-interpret this correctly.
1902 			 * e.g. "127.1" means 127.1.0.0, not 127.0.0.1.
1903 			 */
1904 			bzero(&sin, sizeof sin);
1905 			sin.sin_family = AF_INET;
1906 			sin.sin_len = sizeof sin;
1907 			sin.sin_addr = inet_makeaddr(inet_network(cp), 0);
1908 			if (debug)
1909 				fprintf(stderr, "get_net: v4 addr %s\n",
1910 				    inet_ntoa(sin.sin_addr));
1911 			sa = (struct sockaddr *)&sin;
1912 		}
1913 	}
1914 	if (sa == NULL && (np = getnetbyname(cp)) != NULL) {
1915 		bzero(&sin, sizeof sin);
1916 		sin.sin_family = AF_INET;
1917 		sin.sin_len = sizeof sin;
1918 		sin.sin_addr = inet_makeaddr(np->n_net, 0);
1919 		sa = (struct sockaddr *)&sin;
1920 	}
1921 	if (sa == NULL)
1922 		goto fail;
1923 
1924 	if (maskflg) {
1925 		/* The specified sockaddr is a mask. */
1926 		if (checkmask(sa) != 0)
1927 			goto fail;
1928 		bcopy(sa, &net->nt_mask, sa->sa_len);
1929 		opt_flags |= OP_HAVEMASK;
1930 	} else {
1931 		/* The specified sockaddr is a network address. */
1932 		bcopy(sa, &net->nt_net, sa->sa_len);
1933 
1934 		/* Get a network name for the export list. */
1935 		if (np) {
1936 			name = np->n_name;
1937 		} else if (getnameinfo(sa, sa->sa_len, netname, sizeof netname,
1938 		   NULL, 0, ninumeric) == 0) {
1939 			name = netname;
1940 		} else {
1941 			goto fail;
1942 		}
1943 		if ((net->nt_name = strdup(name)) == NULL)
1944 			out_of_mem();
1945 
1946 		/*
1947 		 * Extract a mask from either a "/<masklen>" suffix, or
1948 		 * from the class of an IPv4 address.
1949 		 */
1950 		if (opt_flags & OP_MASKLEN) {
1951 			preflen = strtol(prefp, NULL, 10);
1952 			if (preflen < 0L || preflen == LONG_MAX)
1953 				goto fail;
1954 			bcopy(sa, &net->nt_mask, sa->sa_len);
1955 			if (makemask(&net->nt_mask, (int)preflen) != 0)
1956 				goto fail;
1957 			opt_flags |= OP_HAVEMASK;
1958 			*p = '/';
1959 		} else if (sa->sa_family == AF_INET &&
1960 		    (opt_flags & OP_MASK) == 0) {
1961 			in_addr_t addr;
1962 
1963 			addr = ((struct sockaddr_in *)sa)->sin_addr.s_addr;
1964 			if (IN_CLASSA(addr))
1965 				preflen = 8;
1966 			else if (IN_CLASSB(addr))
1967 				preflen = 16;
1968 			else if (IN_CLASSC(addr))
1969 				preflen = 24;
1970 			else if (IN_CLASSD(addr))
1971 				preflen = 28;
1972 			else
1973 				preflen = 32;	/* XXX */
1974 
1975 			bcopy(sa, &net->nt_mask, sa->sa_len);
1976 			makemask(&net->nt_mask, (int)preflen);
1977 			opt_flags |= OP_HAVEMASK;
1978 		}
1979 	}
1980 
1981 	if (ai)
1982 		freeaddrinfo(ai);
1983 	return 0;
1984 
1985 fail:
1986 	if (ai)
1987 		freeaddrinfo(ai);
1988 	return 1;
1989 }
1990 
1991 /*
1992  * Parse out the next white space separated field
1993  */
1994 void
1995 nextfield(cp, endcp)
1996 	char **cp;
1997 	char **endcp;
1998 {
1999 	char *p;
2000 
2001 	p = *cp;
2002 	while (*p == ' ' || *p == '\t')
2003 		p++;
2004 	if (*p == '\n' || *p == '\0')
2005 		*cp = *endcp = p;
2006 	else {
2007 		*cp = p++;
2008 		while (*p != ' ' && *p != '\t' && *p != '\n' && *p != '\0')
2009 			p++;
2010 		*endcp = p;
2011 	}
2012 }
2013 
2014 /*
2015  * Get an exports file line. Skip over blank lines and handle line
2016  * continuations.
2017  */
2018 int
2019 get_line()
2020 {
2021 	char *p, *cp;
2022 	int len;
2023 	int totlen, cont_line;
2024 
2025 	/*
2026 	 * Loop around ignoring blank lines and getting all continuation lines.
2027 	 */
2028 	p = line;
2029 	totlen = 0;
2030 	do {
2031 		if (fgets(p, LINESIZ - totlen, exp_file) == NULL)
2032 			return (0);
2033 		len = strlen(p);
2034 		cp = p + len - 1;
2035 		cont_line = 0;
2036 		while (cp >= p &&
2037 		    (*cp == ' ' || *cp == '\t' || *cp == '\n' || *cp == '\\')) {
2038 			if (*cp == '\\')
2039 				cont_line = 1;
2040 			cp--;
2041 			len--;
2042 		}
2043 		if (cont_line) {
2044 			*++cp = ' ';
2045 			len++;
2046 		}
2047 		*++cp = '\0';
2048 		if (len > 0) {
2049 			totlen += len;
2050 			if (totlen >= LINESIZ) {
2051 				syslog(LOG_ERR, "exports line too long");
2052 				exit(2);
2053 			}
2054 			p = cp;
2055 		}
2056 	} while (totlen == 0 || cont_line);
2057 	return (1);
2058 }
2059 
2060 /*
2061  * Parse a description of a credential.
2062  */
2063 void
2064 parsecred(namelist, cr)
2065 	char *namelist;
2066 	struct xucred *cr;
2067 {
2068 	char *name;
2069 	int cnt;
2070 	char *names;
2071 	struct passwd *pw;
2072 	struct group *gr;
2073 	int ngroups, groups[NGROUPS + 1];
2074 
2075 	/*
2076 	 * Set up the unprivileged user.
2077 	 */
2078 	cr->cr_uid = -2;
2079 	cr->cr_groups[0] = -2;
2080 	cr->cr_ngroups = 1;
2081 	/*
2082 	 * Get the user's password table entry.
2083 	 */
2084 	names = strsep(&namelist, " \t\n");
2085 	name = strsep(&names, ":");
2086 	if (isdigit(*name) || *name == '-')
2087 		pw = getpwuid(atoi(name));
2088 	else
2089 		pw = getpwnam(name);
2090 	/*
2091 	 * Credentials specified as those of a user.
2092 	 */
2093 	if (names == NULL) {
2094 		if (pw == NULL) {
2095 			syslog(LOG_ERR, "unknown user: %s", name);
2096 			return;
2097 		}
2098 		cr->cr_uid = pw->pw_uid;
2099 		ngroups = NGROUPS + 1;
2100 		if (getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups))
2101 			syslog(LOG_ERR, "too many groups");
2102 		/*
2103 		 * Convert from int's to gid_t's and compress out duplicate
2104 		 */
2105 		cr->cr_ngroups = ngroups - 1;
2106 		cr->cr_groups[0] = groups[0];
2107 		for (cnt = 2; cnt < ngroups; cnt++)
2108 			cr->cr_groups[cnt - 1] = groups[cnt];
2109 		return;
2110 	}
2111 	/*
2112 	 * Explicit credential specified as a colon separated list:
2113 	 *	uid:gid:gid:...
2114 	 */
2115 	if (pw != NULL)
2116 		cr->cr_uid = pw->pw_uid;
2117 	else if (isdigit(*name) || *name == '-')
2118 		cr->cr_uid = atoi(name);
2119 	else {
2120 		syslog(LOG_ERR, "unknown user: %s", name);
2121 		return;
2122 	}
2123 	cr->cr_ngroups = 0;
2124 	while (names != NULL && *names != '\0' && cr->cr_ngroups < NGROUPS) {
2125 		name = strsep(&names, ":");
2126 		if (isdigit(*name) || *name == '-') {
2127 			cr->cr_groups[cr->cr_ngroups++] = atoi(name);
2128 		} else {
2129 			if ((gr = getgrnam(name)) == NULL) {
2130 				syslog(LOG_ERR, "unknown group: %s", name);
2131 				continue;
2132 			}
2133 			cr->cr_groups[cr->cr_ngroups++] = gr->gr_gid;
2134 		}
2135 	}
2136 	if (names != NULL && *names != '\0' && cr->cr_ngroups == NGROUPS)
2137 		syslog(LOG_ERR, "too many groups");
2138 }
2139 
2140 #define	STRSIZ	(RPCMNT_NAMELEN+RPCMNT_PATHLEN+50)
2141 /*
2142  * Routines that maintain the remote mounttab
2143  */
2144 void
2145 get_mountlist()
2146 {
2147 	struct mountlist *mlp, **mlpp;
2148 	char *host, *dirp, *cp;
2149 	char str[STRSIZ];
2150 	FILE *mlfile;
2151 
2152 	if ((mlfile = fopen(_PATH_RMOUNTLIST, "r")) == NULL) {
2153 		if (errno == ENOENT)
2154 			return;
2155 		else {
2156 			syslog(LOG_ERR, "can't open %s", _PATH_RMOUNTLIST);
2157 			return;
2158 		}
2159 	}
2160 	mlpp = &mlhead;
2161 	while (fgets(str, STRSIZ, mlfile) != NULL) {
2162 		cp = str;
2163 		host = strsep(&cp, " \t\n");
2164 		dirp = strsep(&cp, " \t\n");
2165 		if (host == NULL || dirp == NULL)
2166 			continue;
2167 		mlp = (struct mountlist *)malloc(sizeof (*mlp));
2168 		if (mlp == (struct mountlist *)NULL)
2169 			out_of_mem();
2170 		strncpy(mlp->ml_host, host, RPCMNT_NAMELEN);
2171 		mlp->ml_host[RPCMNT_NAMELEN] = '\0';
2172 		strncpy(mlp->ml_dirp, dirp, RPCMNT_PATHLEN);
2173 		mlp->ml_dirp[RPCMNT_PATHLEN] = '\0';
2174 		mlp->ml_next = (struct mountlist *)NULL;
2175 		*mlpp = mlp;
2176 		mlpp = &mlp->ml_next;
2177 	}
2178 	fclose(mlfile);
2179 }
2180 
2181 void
2182 del_mlist(char *hostp, char *dirp)
2183 {
2184 	struct mountlist *mlp, **mlpp;
2185 	struct mountlist *mlp2;
2186 	FILE *mlfile;
2187 	int fnd = 0;
2188 
2189 	mlpp = &mlhead;
2190 	mlp = mlhead;
2191 	while (mlp) {
2192 		if (!strcmp(mlp->ml_host, hostp) &&
2193 		    (!dirp || !strcmp(mlp->ml_dirp, dirp))) {
2194 			fnd = 1;
2195 			mlp2 = mlp;
2196 			*mlpp = mlp = mlp->ml_next;
2197 			free((caddr_t)mlp2);
2198 		} else {
2199 			mlpp = &mlp->ml_next;
2200 			mlp = mlp->ml_next;
2201 		}
2202 	}
2203 	if (fnd) {
2204 		if ((mlfile = fopen(_PATH_RMOUNTLIST, "w")) == NULL) {
2205 			syslog(LOG_ERR,"can't update %s", _PATH_RMOUNTLIST);
2206 			return;
2207 		}
2208 		mlp = mlhead;
2209 		while (mlp) {
2210 			fprintf(mlfile, "%s %s\n", mlp->ml_host, mlp->ml_dirp);
2211 			mlp = mlp->ml_next;
2212 		}
2213 		fclose(mlfile);
2214 	}
2215 }
2216 
2217 void
2218 add_mlist(hostp, dirp)
2219 	char *hostp, *dirp;
2220 {
2221 	struct mountlist *mlp, **mlpp;
2222 	FILE *mlfile;
2223 
2224 	mlpp = &mlhead;
2225 	mlp = mlhead;
2226 	while (mlp) {
2227 		if (!strcmp(mlp->ml_host, hostp) && !strcmp(mlp->ml_dirp, dirp))
2228 			return;
2229 		mlpp = &mlp->ml_next;
2230 		mlp = mlp->ml_next;
2231 	}
2232 	mlp = (struct mountlist *)malloc(sizeof (*mlp));
2233 	if (mlp == (struct mountlist *)NULL)
2234 		out_of_mem();
2235 	strncpy(mlp->ml_host, hostp, RPCMNT_NAMELEN);
2236 	mlp->ml_host[RPCMNT_NAMELEN] = '\0';
2237 	strncpy(mlp->ml_dirp, dirp, RPCMNT_PATHLEN);
2238 	mlp->ml_dirp[RPCMNT_PATHLEN] = '\0';
2239 	mlp->ml_next = (struct mountlist *)NULL;
2240 	*mlpp = mlp;
2241 	if ((mlfile = fopen(_PATH_RMOUNTLIST, "a")) == NULL) {
2242 		syslog(LOG_ERR, "can't update %s", _PATH_RMOUNTLIST);
2243 		return;
2244 	}
2245 	fprintf(mlfile, "%s %s\n", mlp->ml_host, mlp->ml_dirp);
2246 	fclose(mlfile);
2247 }
2248 
2249 /*
2250  * Free up a group list.
2251  */
2252 void
2253 free_grp(grp)
2254 	struct grouplist *grp;
2255 {
2256 	if (grp->gr_type == GT_HOST) {
2257 		if (grp->gr_ptr.gt_addrinfo != NULL)
2258 			freeaddrinfo(grp->gr_ptr.gt_addrinfo);
2259 	} else if (grp->gr_type == GT_NET) {
2260 		if (grp->gr_ptr.gt_net.nt_name)
2261 			free(grp->gr_ptr.gt_net.nt_name);
2262 	}
2263 	free((caddr_t)grp);
2264 }
2265 
2266 #ifdef DEBUG
2267 void
2268 SYSLOG(int pri, const char *fmt, ...)
2269 {
2270 	va_list ap;
2271 
2272 	va_start(ap, fmt);
2273 	vfprintf(stderr, fmt, ap);
2274 	va_end(ap);
2275 }
2276 #endif /* DEBUG */
2277 
2278 /*
2279  * Check options for consistency.
2280  */
2281 int
2282 check_options(dp)
2283 	struct dirlist *dp;
2284 {
2285 
2286 	if (dp == (struct dirlist *)NULL)
2287 	    return (1);
2288 	if ((opt_flags & (OP_MAPROOT | OP_MAPALL)) == (OP_MAPROOT | OP_MAPALL) ||
2289 	    (opt_flags & (OP_MAPROOT | OP_KERB)) == (OP_MAPROOT | OP_KERB) ||
2290 	    (opt_flags & (OP_MAPALL | OP_KERB)) == (OP_MAPALL | OP_KERB)) {
2291 	    syslog(LOG_ERR, "-mapall, -maproot and -kerb mutually exclusive");
2292 	    return (1);
2293 	}
2294 	if ((opt_flags & OP_MASK) && (opt_flags & OP_NET) == 0) {
2295 		syslog(LOG_ERR, "-mask requires -network");
2296 		return (1);
2297 	}
2298 	if ((opt_flags & OP_NET) && (opt_flags & OP_HAVEMASK) == 0) {
2299 		syslog(LOG_ERR, "-network requires mask specification");
2300 		return (1);
2301 	}
2302 	if ((opt_flags & OP_MASK) && (opt_flags & OP_MASKLEN)) {
2303 		syslog(LOG_ERR, "-mask and /masklen are mutually exclusive");
2304 		return (1);
2305 	}
2306 	if ((opt_flags & OP_ALLDIRS) && dp->dp_left) {
2307 	    syslog(LOG_ERR, "-alldirs has multiple directories");
2308 	    return (1);
2309 	}
2310 	return (0);
2311 }
2312 
2313 /*
2314  * Check an absolute directory path for any symbolic links. Return true
2315  */
2316 int
2317 check_dirpath(dirp)
2318 	char *dirp;
2319 {
2320 	char *cp;
2321 	int ret = 1;
2322 	struct stat sb;
2323 
2324 	cp = dirp + 1;
2325 	while (*cp && ret) {
2326 		if (*cp == '/') {
2327 			*cp = '\0';
2328 			if (lstat(dirp, &sb) < 0 || !S_ISDIR(sb.st_mode))
2329 				ret = 0;
2330 			*cp = '/';
2331 		}
2332 		cp++;
2333 	}
2334 	if (lstat(dirp, &sb) < 0 || !S_ISDIR(sb.st_mode))
2335 		ret = 0;
2336 	return (ret);
2337 }
2338 
2339 /*
2340  * Make a netmask according to the specified prefix length. The ss_family
2341  * and other non-address fields must be initialised before calling this.
2342  */
2343 int
2344 makemask(struct sockaddr_storage *ssp, int bitlen)
2345 {
2346 	u_char *p;
2347 	int bits, i, len;
2348 
2349 	if ((p = sa_rawaddr((struct sockaddr *)ssp, &len)) == NULL)
2350 		return (-1);
2351 	if (bitlen > len * NBBY)
2352 		return (-1);
2353 
2354 	for (i = 0; i < len; i++) {
2355 		bits = (bitlen > NBBY) ? NBBY : bitlen;
2356 		*p++ = (1 << bits) - 1;
2357 		bitlen -= bits;
2358 	}
2359 	return 0;
2360 }
2361 
2362 /*
2363  * Check that the sockaddr is a valid netmask. Returns 0 if the mask
2364  * is acceptable (i.e. of the form 1...10....0).
2365  */
2366 int
2367 checkmask(struct sockaddr *sa)
2368 {
2369 	u_char *mask;
2370 	int i, len;
2371 
2372 	if ((mask = sa_rawaddr(sa, &len)) == NULL)
2373 		return (-1);
2374 
2375 	for (i = 0; i < len; i++)
2376 		if (mask[i] != 0xff)
2377 			break;
2378 	if (i < len) {
2379 		if (~mask[i] & (u_char)(~mask[i] + 1))
2380 			return (-1);
2381 		i++;
2382 	}
2383 	for (; i < len; i++)
2384 		if (mask[i] != 0)
2385 			return (-1);
2386 	return (0);
2387 }
2388 
2389 /*
2390  * Compare two sockaddrs according to a specified mask. Return zero if
2391  * `sa1' matches `sa2' when filtered by the netmask in `samask'.
2392  * If samask is NULL, perform a full comparision.
2393  */
2394 int
2395 sacmp(struct sockaddr *sa1, struct sockaddr *sa2, struct sockaddr *samask)
2396 {
2397 	unsigned char *p1, *p2, *mask;
2398 	int len, i;
2399 
2400 	if (sa1->sa_family != sa2->sa_family ||
2401 	    (p1 = sa_rawaddr(sa1, &len)) == NULL ||
2402 	    (p2 = sa_rawaddr(sa2, NULL)) == NULL)
2403 		return (1);
2404 
2405 	switch (sa1->sa_family) {
2406 	case AF_INET6:
2407 		if (((struct sockaddr_in6 *)sa1)->sin6_scope_id !=
2408 		    ((struct sockaddr_in6 *)sa2)->sin6_scope_id)
2409 			return (1);
2410 		break;
2411 	}
2412 
2413 	/* Simple binary comparison if no mask specified. */
2414 	if (samask == NULL)
2415 		return (memcmp(p1, p2, len));
2416 
2417 	/* Set up the mask, and do a mask-based comparison. */
2418 	if (sa1->sa_family != samask->sa_family ||
2419 	    (mask = sa_rawaddr(samask, NULL)) == NULL)
2420 		return (1);
2421 
2422 	for (i = 0; i < len; i++)
2423 		if ((p1[i] & mask[i]) != (p2[i] & mask[i]))
2424 			return (1);
2425 	return (0);
2426 }
2427 
2428 /*
2429  * Return a pointer to the part of the sockaddr that contains the
2430  * raw address, and set *nbytes to its length in bytes. Returns
2431  * NULL if the address family is unknown.
2432  */
2433 void *
2434 sa_rawaddr(struct sockaddr *sa, int *nbytes) {
2435 	void *p;
2436 	int len;
2437 
2438 	switch (sa->sa_family) {
2439 	case AF_INET:
2440 		len = sizeof(((struct sockaddr_in *)sa)->sin_addr);
2441 		p = &((struct sockaddr_in *)sa)->sin_addr;
2442 		break;
2443 	case AF_INET6:
2444 		len = sizeof(((struct sockaddr_in6 *)sa)->sin6_addr);
2445 		p = &((struct sockaddr_in6 *)sa)->sin6_addr;
2446 		break;
2447 	default:
2448 		p = NULL;
2449 		len = 0;
2450 	}
2451 
2452 	if (nbytes != NULL)
2453 		*nbytes = len;
2454 	return (p);
2455 }
2456 
2457 void
2458 huphandler(int sig)
2459 {
2460 	got_sighup = 1;
2461 }
2462 
2463 void terminate(sig)
2464 int sig;
2465 {
2466 	close(mountdlockfd);
2467 	unlink(MOUNTDLOCK);
2468 	rpcb_unset(RPCPROG_MNT, RPCMNT_VER1, NULL);
2469 	rpcb_unset(RPCPROG_MNT, RPCMNT_VER3, NULL);
2470 	exit (0);
2471 }
2472