xref: /freebsd/sbin/mount_nfs/mount_nfs.c (revision f856af0466c076beef4ea9b15d088e1119a945b8)
1 /*
2  * Copyright (c) 1992, 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  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #if 0
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1992, 1993, 1994\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 static char sccsid[] = "@(#)mount_nfs.c	8.11 (Berkeley) 5/4/95";
42 #endif /* not lint */
43 #endif
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 #include <sys/param.h>
48 #include <sys/mount.h>
49 #include <sys/socket.h>
50 #include <sys/stat.h>
51 #include <sys/syslog.h>
52 #include <sys/uio.h>
53 
54 #include <rpc/rpc.h>
55 #include <rpc/pmap_clnt.h>
56 #include <rpc/pmap_prot.h>
57 
58 #include <nfs/rpcv2.h>
59 #include <nfs/nfsproto.h>
60 #include <nfsclient/nfs.h>
61 #include <nfsclient/nfsargs.h>
62 
63 #include <arpa/inet.h>
64 
65 #include <ctype.h>
66 #include <err.h>
67 #include <errno.h>
68 #include <fcntl.h>
69 #include <netdb.h>
70 #include <stdio.h>
71 #include <stdlib.h>
72 #include <string.h>
73 #include <strings.h>
74 #include <sysexits.h>
75 #include <unistd.h>
76 
77 #include "mntopts.h"
78 #include "mounttab.h"
79 
80 #define	ALTF_BG		0x1
81 #define ALTF_NOCONN	0x2
82 #define ALTF_DUMBTIMR	0x4
83 #define ALTF_INTR	0x8
84 #define ALTF_NFSV3	0x20
85 #define ALTF_RDIRPLUS	0x40
86 #define ALTF_MNTUDP	0x80
87 #define ALTF_RESVPORT	0x100
88 #define ALTF_SEQPACKET	0x200
89 #define ALTF_SOFT	0x800
90 #define ALTF_TCP	0x1000
91 #define ALTF_PORT	0x2000
92 #define ALTF_NFSV2	0x4000
93 #define ALTF_ACREGMIN	0x8000
94 #define ALTF_ACREGMAX	0x10000
95 #define ALTF_ACDIRMIN	0x20000
96 #define ALTF_ACDIRMAX	0x40000
97 #define ALTF_NOLOCKD	0x80000
98 #define ALTF_NOINET4	0x100000
99 #define ALTF_NOINET6	0x200000
100 
101 struct mntopt mopts[] = {
102 	MOPT_STDOPTS,
103 	MOPT_FORCE,
104 	MOPT_UPDATE,
105 	MOPT_ASYNC,
106 	{ "bg", 0, ALTF_BG, 1 },
107 	{ "conn", 1, ALTF_NOCONN, 1 },
108 	{ "dumbtimer", 0, ALTF_DUMBTIMR, 1 },
109 	{ "intr", 0, ALTF_INTR, 1 },
110 	{ "nfsv3", 0, ALTF_NFSV3, 1 },
111 	{ "rdirplus", 0, ALTF_RDIRPLUS, 1 },
112 	{ "mntudp", 0, ALTF_MNTUDP, 1 },
113 	{ "resvport", 0, ALTF_RESVPORT, 1 },
114 	{ "soft", 0, ALTF_SOFT, 1 },
115 	{ "tcp", 0, ALTF_TCP, 1 },
116 	{ "port=", 0, ALTF_PORT, 1 },
117 	{ "nfsv2", 0, ALTF_NFSV2, 1 },
118 	{ "acregmin=", 0, ALTF_ACREGMIN, 1 },
119 	{ "acregmax=", 0, ALTF_ACREGMAX, 1 },
120 	{ "acdirmin=", 0, ALTF_ACDIRMIN, 1 },
121 	{ "acdirmax=", 0, ALTF_ACDIRMAX, 1 },
122 	{ "lockd", 1, ALTF_NOLOCKD, 1 },
123 	{ "inet4", 1, ALTF_NOINET4, 1 },
124 	{ "inet6", 1, ALTF_NOINET6, 1 },
125 	MOPT_END
126 };
127 
128 struct nfs_args nfsdefargs = {
129 	NFS_ARGSVERSION,
130 	NULL,
131 	sizeof (struct sockaddr_in),
132 	SOCK_DGRAM,
133 	0,
134 	NULL,
135 	0,
136 	NFSMNT_RESVPORT,
137 	NFS_WSIZE,
138 	NFS_RSIZE,
139 	NFS_READDIRSIZE,
140 	10,
141 	NFS_RETRANS,
142 	NFS_MAXGRPS,
143 	NFS_DEFRAHEAD,
144 	0,			/* was: NQ_DEFLEASE */
145 	NFS_MAXDEADTHRESH,	/* was: NQ_DEADTHRESH */
146 	NULL,
147 	/* args version 4 */
148 	NFS_MINATTRTIMO,
149 	NFS_MAXATTRTIMO,
150 	NFS_MINDIRATTRTIMO,
151 	NFS_MAXDIRATTRTIMO,
152 };
153 
154 /* Table for af,sotype -> netid conversions. */
155 struct nc_protos {
156 	char *netid;
157 	int af;
158 	int sotype;
159 } nc_protos[] = {
160 	{"udp",		AF_INET,	SOCK_DGRAM},
161 	{"tcp",		AF_INET,	SOCK_STREAM},
162 	{"udp6",	AF_INET6,	SOCK_DGRAM},
163 	{"tcp6",	AF_INET6,	SOCK_STREAM},
164 	{NULL,		0,		0}
165 };
166 
167 struct nfhret {
168 	u_long		stat;
169 	long		vers;
170 	long		auth;
171 	long		fhsize;
172 	u_char		nfh[NFSX_V3FHMAX];
173 };
174 #define	BGRND	1
175 #define	ISBGRND	2
176 #define	OF_NOINET4	4
177 #define	OF_NOINET6	8
178 int retrycnt = -1;
179 int opflags = 0;
180 int nfsproto = IPPROTO_UDP;
181 int mnttcp_ok = 1;
182 char *portspec = NULL;	/* Server nfs port; NULL means look up via rpcbind. */
183 enum mountmode {
184 	ANY,
185 	V2,
186 	V3
187 } mountmode = ANY;
188 
189 /* Return codes for nfs_tryproto. */
190 enum tryret {
191 	TRYRET_SUCCESS,
192 	TRYRET_TIMEOUT,		/* No response received. */
193 	TRYRET_REMOTEERR,	/* Error received from remote server. */
194 	TRYRET_LOCALERR		/* Local failure. */
195 };
196 
197 int	getnfsargs(char *, struct nfs_args *);
198 /* void	set_rpc_maxgrouplist(int); */
199 struct netconfig *getnetconf_cached(const char *netid);
200 char	*netidbytype(int af, int sotype);
201 void	usage(void) __dead2;
202 int	xdr_dir(XDR *, char *);
203 int	xdr_fh(XDR *, struct nfhret *);
204 enum tryret nfs_tryproto(struct nfs_args *nfsargsp, struct addrinfo *ai,
205     char *hostp, char *spec, char **errstr);
206 enum tryret returncode(enum clnt_stat stat, struct rpc_err *rpcerr);
207 
208 /*
209  * Used to set mount flags with getmntopts.  Call with dir=TRUE to
210  * initialize altflags from the current mount flags.  Call with
211  * dir=FALSE to update mount flags with the new value of altflags after
212  * the call to getmntopts.
213  */
214 static void
215 set_flags(int* altflags, int* nfsflags, int dir)
216 {
217 #define F2(af, nf)					\
218 	if (dir) {					\
219 		if (*nfsflags & NFSMNT_##nf)		\
220 			*altflags |= ALTF_##af;		\
221 		else					\
222 			*altflags &= ~ALTF_##af;	\
223 	} else {					\
224 		if (*altflags & ALTF_##af)		\
225 			*nfsflags |= NFSMNT_##nf;	\
226 		else					\
227 			*nfsflags &= ~NFSMNT_##nf;	\
228 	}
229 #define F(f)	F2(f,f)
230 
231 	F(NOCONN);
232 	F(DUMBTIMR);
233 	F2(INTR, INT);
234 	F(RDIRPLUS);
235 	F(RESVPORT);
236 	F(SOFT);
237 	F(ACREGMIN);
238 	F(ACREGMAX);
239 	F(ACDIRMIN);
240 	F(ACDIRMAX);
241 	F(NOLOCKD);
242 
243 #undef F
244 #undef F2
245 }
246 
247 int
248 main(int argc, char *argv[])
249 {
250 	int c;
251 	struct nfs_args *nfsargsp;
252 	struct nfs_args nfsargs;
253 	struct iovec *iov;
254 	int mntflags, altflags, num;
255 	int iovlen;
256 	char *name, *p, *spec, *fstype;
257 	char mntpath[MAXPATHLEN], errmsg[255];
258 
259 	mntflags = 0;
260 	altflags = 0;
261 	nfsargs = nfsdefargs;
262 	nfsargsp = &nfsargs;
263 	iov = NULL;
264 	iovlen = 0;
265 	memset(errmsg, 0, sizeof(errmsg));
266 
267 	fstype = strrchr(argv[0], '_');
268 	if (fstype == NULL)
269 		errx(EX_USAGE, "argv[0] must end in _fstype");
270 
271 	++fstype;
272 
273 	while ((c = getopt(argc, argv,
274 	    "23a:bcdD:g:I:iLlNo:PR:r:sTt:w:x:U")) != -1)
275 		switch (c) {
276 		case '2':
277 			mountmode = V2;
278 			break;
279 		case '3':
280 			mountmode = V3;
281 			break;
282 		case 'a':
283 			num = strtol(optarg, &p, 10);
284 			if (*p || num < 0)
285 				errx(1, "illegal -a value -- %s", optarg);
286 			nfsargsp->readahead = num;
287 			nfsargsp->flags |= NFSMNT_READAHEAD;
288 			break;
289 		case 'b':
290 			opflags |= BGRND;
291 			break;
292 		case 'c':
293 			nfsargsp->flags |= NFSMNT_NOCONN;
294 			break;
295 		case 'D':
296 			num = strtol(optarg, &p, 10);
297 			if (*p || num <= 0)
298 				errx(1, "illegal -D value -- %s", optarg);
299 			nfsargsp->deadthresh = num;
300 			nfsargsp->flags |= NFSMNT_DEADTHRESH;
301 			break;
302 		case 'd':
303 			nfsargsp->flags |= NFSMNT_DUMBTIMR;
304 			break;
305 #if 0 /* XXXX */
306 		case 'g':
307 			num = strtol(optarg, &p, 10);
308 			if (*p || num <= 0)
309 				errx(1, "illegal -g value -- %s", optarg);
310 			set_rpc_maxgrouplist(num);
311 			nfsargsp->maxgrouplist = num;
312 			nfsargsp->flags |= NFSMNT_MAXGRPS;
313 			break;
314 #endif
315 		case 'I':
316 			num = strtol(optarg, &p, 10);
317 			if (*p || num <= 0)
318 				errx(1, "illegal -I value -- %s", optarg);
319 			nfsargsp->readdirsize = num;
320 			nfsargsp->flags |= NFSMNT_READDIRSIZE;
321 			break;
322 		case 'i':
323 			nfsargsp->flags |= NFSMNT_INT;
324 			break;
325 		case 'L':
326 			nfsargsp->flags |= NFSMNT_NOLOCKD;
327 			break;
328 		case 'l':
329 			nfsargsp->flags |= NFSMNT_RDIRPLUS;
330 			break;
331 		case 'N':
332 			nfsargsp->flags &= ~NFSMNT_RESVPORT;
333 			break;
334 		case 'o':
335 			altflags = 0;
336 			set_flags(&altflags, &nfsargsp->flags, TRUE);
337 			if (mountmode == V2)
338 				altflags |= ALTF_NFSV2;
339 			else if (mountmode == V3)
340 				altflags |= ALTF_NFSV3;
341 			getmntopts(optarg, mopts, &mntflags, &altflags);
342 			set_flags(&altflags, &nfsargsp->flags, FALSE);
343 			/*
344 			 * Handle altflags which don't map directly to
345 			 * mount flags.
346 			 */
347 			if (altflags & ALTF_BG)
348 				opflags |= BGRND;
349 			if (altflags & ALTF_NOINET4)
350 				opflags |= OF_NOINET4;
351 			if (altflags & ALTF_NOINET6)
352 				opflags |= OF_NOINET6;
353 			if (altflags & ALTF_MNTUDP)
354 				mnttcp_ok = 0;
355 			if (altflags & ALTF_TCP) {
356 				nfsargsp->sotype = SOCK_STREAM;
357 				nfsproto = IPPROTO_TCP;
358 			}
359 			if (altflags & ALTF_PORT) {
360 				/*
361 				 * XXX Converting from a string to an int
362 				 * and back again is silly, and we should
363 				 * allow /etc/services names.
364 				 */
365 				p = strstr(optarg, "port=");
366 				if (p) {
367 					asprintf(&portspec, "%d",
368 					    atoi(p + 5));
369 					if (portspec == NULL)
370 						err(1, "asprintf");
371 				}
372 			}
373 			mountmode = ANY;
374 			if (altflags & ALTF_NFSV2)
375 				mountmode = V2;
376 			if (altflags & ALTF_NFSV3)
377 				mountmode = V3;
378 			if (altflags & ALTF_ACREGMIN) {
379 				p = strstr(optarg, "acregmin=");
380 				if (p)
381 					nfsargsp->acregmin = atoi(p + 9);
382 			}
383 			if (altflags & ALTF_ACREGMAX) {
384 				p = strstr(optarg, "acregmax=");
385 				if (p)
386 					nfsargsp->acregmax = atoi(p + 9);
387 			}
388 			if (altflags & ALTF_ACDIRMIN) {
389 				p = strstr(optarg, "acdirmin=");
390 				if (p)
391 					nfsargsp->acdirmin = atoi(p + 9);
392 			}
393 			if (altflags & ALTF_ACDIRMAX) {
394 				p = strstr(optarg, "acdirmax=");
395 				if (p)
396 					nfsargsp->acdirmax = atoi(p + 9);
397 			}
398 			break;
399 		case 'P':
400 			/* obsolete for NFSMNT_RESVPORT, now default */
401 			break;
402 		case 'R':
403 			num = strtol(optarg, &p, 10);
404 			if (*p || num < 0)
405 				errx(1, "illegal -R value -- %s", optarg);
406 			retrycnt = num;
407 			break;
408 		case 'r':
409 			num = strtol(optarg, &p, 10);
410 			if (*p || num <= 0)
411 				errx(1, "illegal -r value -- %s", optarg);
412 			nfsargsp->rsize = num;
413 			nfsargsp->flags |= NFSMNT_RSIZE;
414 			break;
415 		case 's':
416 			nfsargsp->flags |= NFSMNT_SOFT;
417 			break;
418 		case 'T':
419 			nfsargsp->sotype = SOCK_STREAM;
420 			nfsproto = IPPROTO_TCP;
421 			break;
422 		case 't':
423 			num = strtol(optarg, &p, 10);
424 			if (*p || num <= 0)
425 				errx(1, "illegal -t value -- %s", optarg);
426 			nfsargsp->timeo = num;
427 			nfsargsp->flags |= NFSMNT_TIMEO;
428 			break;
429 		case 'w':
430 			num = strtol(optarg, &p, 10);
431 			if (*p || num <= 0)
432 				errx(1, "illegal -w value -- %s", optarg);
433 			nfsargsp->wsize = num;
434 			nfsargsp->flags |= NFSMNT_WSIZE;
435 			break;
436 		case 'x':
437 			num = strtol(optarg, &p, 10);
438 			if (*p || num <= 0)
439 				errx(1, "illegal -x value -- %s", optarg);
440 			nfsargsp->retrans = num;
441 			nfsargsp->flags |= NFSMNT_RETRANS;
442 			break;
443 		case 'U':
444 			mnttcp_ok = 0;
445 			break;
446 		default:
447 			usage();
448 			break;
449 		}
450 	argc -= optind;
451 	argv += optind;
452 
453 	if (argc != 2) {
454 		usage();
455 		/* NOTREACHED */
456 	}
457 
458 	spec = *argv++;
459 	name = *argv;
460 
461 	if (retrycnt == -1)
462 		/* The default is to keep retrying forever. */
463 		retrycnt = 0;
464 	if (!getnfsargs(spec, nfsargsp))
465 		exit(1);
466 
467 	/* resolve the mountpoint with realpath(3) */
468 	(void)checkpath(name, mntpath);
469 
470 	build_iovec(&iov, &iovlen, "nfs_args", nfsargsp, sizeof(*nfsargsp));
471 	build_iovec(&iov, &iovlen, "fstype", fstype, (size_t)-1);
472 	build_iovec(&iov, &iovlen, "fspath", mntpath, (size_t)-1);
473 	build_iovec(&iov, &iovlen, "errmsg", errmsg, sizeof(errmsg));
474 
475 	if (nmount(iov, iovlen, mntflags))
476 		err(1, "%s, %s", mntpath, errmsg);
477 
478 	exit(0);
479 }
480 
481 int
482 getnfsargs(char *spec, struct nfs_args *nfsargsp)
483 {
484 	struct addrinfo hints, *ai_nfs, *ai;
485 	enum tryret ret;
486 	int ecode, speclen, remoteerr;
487 	char *hostp, *delimp, *errstr;
488 	size_t len;
489 	static char nam[MNAMELEN + 1];
490 
491 	if ((delimp = strrchr(spec, ':')) != NULL) {
492 		hostp = spec;
493 		spec = delimp + 1;
494 	} else if ((delimp = strrchr(spec, '@')) != NULL) {
495 		warnx("path@server syntax is deprecated, use server:path");
496 		hostp = delimp + 1;
497 	} else {
498 		warnx("no <host>:<dirpath> nfs-name");
499 		return (0);
500 	}
501 	*delimp = '\0';
502 
503 	/*
504 	 * If there has been a trailing slash at mounttime it seems
505 	 * that some mountd implementations fail to remove the mount
506 	 * entries from their mountlist while unmounting.
507 	 */
508 	for (speclen = strlen(spec);
509 		speclen > 1 && spec[speclen - 1] == '/';
510 		speclen--)
511 		spec[speclen - 1] = '\0';
512 	if (strlen(hostp) + strlen(spec) + 1 > MNAMELEN) {
513 		warnx("%s:%s: %s", hostp, spec, strerror(ENAMETOOLONG));
514 		return (0);
515 	}
516 	/* Make both '@' and ':' notations equal */
517 	if (*hostp != '\0') {
518 		len = strlen(hostp);
519 		memmove(nam, hostp, len);
520 		nam[len] = ':';
521 		memmove(nam + len + 1, spec, speclen);
522 		nam[len + speclen + 1] = '\0';
523 	}
524 
525 	/*
526 	 * Handle an internet host address.
527 	 */
528 	memset(&hints, 0, sizeof hints);
529 	hints.ai_flags = AI_NUMERICHOST;
530 	hints.ai_socktype = nfsargsp->sotype;
531 	if (getaddrinfo(hostp, portspec, &hints, &ai_nfs) != 0) {
532 		hints.ai_flags = 0;
533 		if ((ecode = getaddrinfo(hostp, portspec, &hints, &ai_nfs))
534 		    != 0) {
535 			if (portspec == NULL)
536 				errx(1, "%s: %s", hostp, gai_strerror(ecode));
537 			else
538 				errx(1, "%s:%s: %s", hostp, portspec,
539 				    gai_strerror(ecode));
540 			return (0);
541 		}
542 	}
543 
544 	ret = TRYRET_LOCALERR;
545 	for (;;) {
546 		/*
547 		 * Try each entry returned by getaddrinfo(). Note the
548 		 * occurence of remote errors by setting `remoteerr'.
549 		 */
550 		remoteerr = 0;
551 		for (ai = ai_nfs; ai != NULL; ai = ai->ai_next) {
552 			if ((ai->ai_family == AF_INET6) &&
553 			    (opflags & OF_NOINET6))
554 				continue;
555 			if ((ai->ai_family == AF_INET) &&
556 			    (opflags & OF_NOINET4))
557 				continue;
558 			ret = nfs_tryproto(nfsargsp, ai, hostp, spec, &errstr);
559 			if (ret == TRYRET_SUCCESS)
560 				break;
561 			if (ret != TRYRET_LOCALERR)
562 				remoteerr = 1;
563 			if ((opflags & ISBGRND) == 0)
564 				fprintf(stderr, "%s\n", errstr);
565 		}
566 		if (ret == TRYRET_SUCCESS)
567 			break;
568 
569 		/* Exit if all errors were local. */
570 		if (!remoteerr)
571 			exit(1);
572 
573 		/*
574 		 * If retrycnt == 0, we are to keep retrying forever.
575 		 * Otherwise decrement it, and exit if it hits zero.
576 		 */
577 		if (retrycnt != 0 && --retrycnt == 0)
578 			exit(1);
579 
580 		if ((opflags & (BGRND | ISBGRND)) == BGRND) {
581 			warnx("Cannot immediately mount %s:%s, backgrounding",
582 			    hostp, spec);
583 			opflags |= ISBGRND;
584 			if (daemon(0, 0) != 0)
585 				err(1, "daemon");
586 		}
587 		sleep(60);
588 	}
589 	freeaddrinfo(ai_nfs);
590 	nfsargsp->hostname = nam;
591 	/* Add mounted file system to PATH_MOUNTTAB */
592 	if (!add_mtab(hostp, spec))
593 		warnx("can't update %s for %s:%s", PATH_MOUNTTAB, hostp, spec);
594 	return (1);
595 }
596 
597 /*
598  * Try to set up the NFS arguments according to the address
599  * family, protocol (and possibly port) specified in `ai'.
600  *
601  * Returns TRYRET_SUCCESS if successful, or:
602  *   TRYRET_TIMEOUT		The server did not respond.
603  *   TRYRET_REMOTEERR		The server reported an error.
604  *   TRYRET_LOCALERR		Local failure.
605  *
606  * In all error cases, *errstr will be set to a statically-allocated string
607  * describing the error.
608  */
609 enum tryret
610 nfs_tryproto(struct nfs_args *nfsargsp, struct addrinfo *ai, char *hostp,
611     char *spec, char **errstr)
612 {
613 	static char errbuf[256];
614 	struct sockaddr_storage nfs_ss;
615 	struct netbuf nfs_nb;
616 	struct nfhret nfhret;
617 	struct timeval try;
618 	struct rpc_err rpcerr;
619 	CLIENT *clp;
620 	struct netconfig *nconf, *nconf_mnt;
621 	char *netid, *netid_mnt;
622 	int doconnect, nfsvers, mntvers;
623 	enum clnt_stat stat;
624 	enum mountmode trymntmode;
625 
626 	trymntmode = mountmode;
627 	errbuf[0] = '\0';
628 	*errstr = errbuf;
629 
630 	if ((netid = netidbytype(ai->ai_family, nfsargsp->sotype)) == NULL) {
631 		snprintf(errbuf, sizeof errbuf,
632 		    "af %d sotype %d not supported", ai->ai_family,
633 		    nfsargsp->sotype);
634 		return (TRYRET_LOCALERR);
635 	}
636 	if ((nconf = getnetconf_cached(netid)) == NULL) {
637 		snprintf(errbuf, sizeof errbuf, "%s: %s", netid, nc_sperror());
638 		return (TRYRET_LOCALERR);
639 	}
640 	/* The RPCPROG_MNT netid may be different. */
641 	if (mnttcp_ok) {
642 		netid_mnt = netid;
643 		nconf_mnt = nconf;
644 	} else {
645 		if ((netid_mnt = netidbytype(ai->ai_family, SOCK_DGRAM))
646 		     == NULL) {
647 			snprintf(errbuf, sizeof errbuf,
648 			    "af %d sotype SOCK_DGRAM not supported",
649 			     ai->ai_family);
650 			return (TRYRET_LOCALERR);
651 		}
652 		if ((nconf_mnt = getnetconf_cached(netid_mnt)) == NULL) {
653 			snprintf(errbuf, sizeof errbuf, "%s: %s", netid_mnt,
654 			    nc_sperror());
655 			return (TRYRET_LOCALERR);
656 		}
657 	}
658 
659 tryagain:
660 	if (trymntmode == V2) {
661 		nfsvers = 2;
662 		mntvers = 1;
663 	} else {
664 		nfsvers = 3;
665 		mntvers = 3;
666 	}
667 
668 	if (portspec != NULL) {
669 		/* `ai' contains the complete nfsd sockaddr. */
670 		nfs_nb.buf = ai->ai_addr;
671 		nfs_nb.len = nfs_nb.maxlen = ai->ai_addrlen;
672 	} else {
673 		/* Ask the remote rpcbind. */
674 		nfs_nb.buf = &nfs_ss;
675 		nfs_nb.len = nfs_nb.maxlen = sizeof nfs_ss;
676 
677 		if (!rpcb_getaddr(RPCPROG_NFS, nfsvers, nconf, &nfs_nb,
678 		    hostp)) {
679 			if (rpc_createerr.cf_stat == RPC_PROGVERSMISMATCH &&
680 			    trymntmode == ANY) {
681 				trymntmode = V2;
682 				goto tryagain;
683 			}
684 			snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s",
685 			    netid, hostp, spec,
686 			    clnt_spcreateerror("RPCPROG_NFS"));
687 			return (returncode(rpc_createerr.cf_stat,
688 			    &rpc_createerr.cf_error));
689 		}
690 	}
691 
692 	/* Check that the server (nfsd) responds on the port we have chosen. */
693 	clp = clnt_tli_create(RPC_ANYFD, nconf, &nfs_nb, RPCPROG_NFS, nfsvers,
694 	    0, 0);
695 	if (clp == NULL) {
696 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid,
697 		    hostp, spec, clnt_spcreateerror("nfsd: RPCPROG_NFS"));
698 		return (returncode(rpc_createerr.cf_stat,
699 		    &rpc_createerr.cf_error));
700 	}
701 	if (nfsargsp->sotype == SOCK_DGRAM &&
702 	    !(nfsargsp->flags & NFSMNT_NOCONN)) {
703 		/*
704 		 * Use connect(), to match what the kernel does. This
705 		 * catches cases where the server responds from the
706 		 * wrong source address.
707 		 */
708 		doconnect = 1;
709 		if (!clnt_control(clp, CLSET_CONNECT, (char *)&doconnect)) {
710 			clnt_destroy(clp);
711 			snprintf(errbuf, sizeof errbuf,
712 			    "[%s] %s:%s: CLSET_CONNECT failed", netid, hostp,
713 			    spec);
714 			return (TRYRET_LOCALERR);
715 		}
716 	}
717 
718 	try.tv_sec = 10;
719 	try.tv_usec = 0;
720 	stat = clnt_call(clp, NFSPROC_NULL, (xdrproc_t)xdr_void, NULL,
721 			 (xdrproc_t)xdr_void, NULL,
722 	    try);
723 	if (stat != RPC_SUCCESS) {
724 		if (stat == RPC_PROGVERSMISMATCH && trymntmode == ANY) {
725 			clnt_destroy(clp);
726 			trymntmode = V2;
727 			goto tryagain;
728 		}
729 		clnt_geterr(clp, &rpcerr);
730 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid,
731 		    hostp, spec, clnt_sperror(clp, "NFSPROC_NULL"));
732 		clnt_destroy(clp);
733 		return (returncode(stat, &rpcerr));
734 	}
735 	clnt_destroy(clp);
736 
737 	/* Send the RPCMNT_MOUNT RPC to get the root filehandle. */
738 	try.tv_sec = 10;
739 	try.tv_usec = 0;
740 	clp = clnt_tp_create(hostp, RPCPROG_MNT, mntvers, nconf_mnt);
741 	if (clp == NULL) {
742 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid_mnt,
743 		    hostp, spec, clnt_spcreateerror("RPCMNT: clnt_create"));
744 		return (returncode(rpc_createerr.cf_stat,
745 		    &rpc_createerr.cf_error));
746 	}
747 	clp->cl_auth = authsys_create_default();
748 	nfhret.auth = RPCAUTH_UNIX;
749 	nfhret.vers = mntvers;
750 	stat = clnt_call(clp, RPCMNT_MOUNT, (xdrproc_t)xdr_dir, spec,
751 			 (xdrproc_t)xdr_fh, &nfhret,
752 	    try);
753 	auth_destroy(clp->cl_auth);
754 	if (stat != RPC_SUCCESS) {
755 		if (stat == RPC_PROGVERSMISMATCH && trymntmode == ANY) {
756 			clnt_destroy(clp);
757 			trymntmode = V2;
758 			goto tryagain;
759 		}
760 		clnt_geterr(clp, &rpcerr);
761 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid_mnt,
762 		    hostp, spec, clnt_sperror(clp, "RPCPROG_MNT"));
763 		clnt_destroy(clp);
764 		return (returncode(stat, &rpcerr));
765 	}
766 	clnt_destroy(clp);
767 
768 	if (nfhret.stat != 0) {
769 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid_mnt,
770 		    hostp, spec, strerror(nfhret.stat));
771 		return (TRYRET_REMOTEERR);
772 	}
773 
774 	/*
775 	 * Store the filehandle and server address in nfsargsp, making
776 	 * sure to copy any locally allocated structures.
777 	 */
778 	nfsargsp->addrlen = nfs_nb.len;
779 	nfsargsp->addr = malloc(nfsargsp->addrlen);
780 	nfsargsp->fhsize = nfhret.fhsize;
781 	nfsargsp->fh = malloc(nfsargsp->fhsize);
782 	if (nfsargsp->addr == NULL || nfsargsp->fh == NULL)
783 		err(1, "malloc");
784 	bcopy(nfs_nb.buf, nfsargsp->addr, nfsargsp->addrlen);
785 	bcopy(nfhret.nfh, nfsargsp->fh, nfsargsp->fhsize);
786 
787 	if (nfsvers == 3)
788 		nfsargsp->flags |= NFSMNT_NFSV3;
789 	else
790 		nfsargsp->flags &= ~NFSMNT_NFSV3;
791 
792 	return (TRYRET_SUCCESS);
793 }
794 
795 
796 /*
797  * Catagorise a RPC return status and error into an `enum tryret'
798  * return code.
799  */
800 enum tryret
801 returncode(enum clnt_stat stat, struct rpc_err *rpcerr)
802 {
803 	switch (stat) {
804 	case RPC_TIMEDOUT:
805 		return (TRYRET_TIMEOUT);
806 	case RPC_PMAPFAILURE:
807 	case RPC_PROGNOTREGISTERED:
808 	case RPC_PROGVERSMISMATCH:
809 	/* XXX, these can be local or remote. */
810 	case RPC_CANTSEND:
811 	case RPC_CANTRECV:
812 		return (TRYRET_REMOTEERR);
813 	case RPC_SYSTEMERROR:
814 		switch (rpcerr->re_errno) {
815 		case ETIMEDOUT:
816 			return (TRYRET_TIMEOUT);
817 		case ENOMEM:
818 			break;
819 		default:
820 			return (TRYRET_REMOTEERR);
821 		}
822 		/* FALLTHROUGH */
823 	default:
824 		break;
825 	}
826 	return (TRYRET_LOCALERR);
827 }
828 
829 /*
830  * Look up a netid based on an address family and socket type.
831  * `af' is the address family, and `sotype' is SOCK_DGRAM or SOCK_STREAM.
832  *
833  * XXX there should be a library function for this.
834  */
835 char *
836 netidbytype(int af, int sotype)
837 {
838 	struct nc_protos *p;
839 
840 	for (p = nc_protos; p->netid != NULL; p++) {
841 		if (af != p->af || sotype != p->sotype)
842 			continue;
843 		return (p->netid);
844 	}
845 	return (NULL);
846 }
847 
848 /*
849  * Look up a netconfig entry based on a netid, and cache the result so
850  * that we don't need to remember to call freenetconfigent().
851  *
852  * Otherwise it behaves just like getnetconfigent(), so nc_*error()
853  * work on failure.
854  */
855 struct netconfig *
856 getnetconf_cached(const char *netid)
857 {
858 	static struct nc_entry {
859 		struct netconfig *nconf;
860 		struct nc_entry *next;
861 	} *head;
862 	struct nc_entry *p;
863 	struct netconfig *nconf;
864 
865 	for (p = head; p != NULL; p = p->next)
866 		if (strcmp(netid, p->nconf->nc_netid) == 0)
867 			return (p->nconf);
868 
869 	if ((nconf = getnetconfigent(netid)) == NULL)
870 		return (NULL);
871 	if ((p = malloc(sizeof(*p))) == NULL)
872 		err(1, "malloc");
873 	p->nconf = nconf;
874 	p->next = head;
875 	head = p;
876 
877 	return (p->nconf);
878 }
879 
880 /*
881  * xdr routines for mount rpc's
882  */
883 int
884 xdr_dir(XDR *xdrsp, char *dirp)
885 {
886 	return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN));
887 }
888 
889 int
890 xdr_fh(XDR *xdrsp, struct nfhret *np)
891 {
892 	int i;
893 	long auth, authcnt, authfnd = 0;
894 
895 	if (!xdr_u_long(xdrsp, &np->stat))
896 		return (0);
897 	if (np->stat)
898 		return (1);
899 	switch (np->vers) {
900 	case 1:
901 		np->fhsize = NFSX_V2FH;
902 		return (xdr_opaque(xdrsp, (caddr_t)np->nfh, NFSX_V2FH));
903 	case 3:
904 		if (!xdr_long(xdrsp, &np->fhsize))
905 			return (0);
906 		if (np->fhsize <= 0 || np->fhsize > NFSX_V3FHMAX)
907 			return (0);
908 		if (!xdr_opaque(xdrsp, (caddr_t)np->nfh, np->fhsize))
909 			return (0);
910 		if (!xdr_long(xdrsp, &authcnt))
911 			return (0);
912 		for (i = 0; i < authcnt; i++) {
913 			if (!xdr_long(xdrsp, &auth))
914 				return (0);
915 			if (auth == np->auth)
916 				authfnd++;
917 		}
918 		/*
919 		 * Some servers, such as DEC's OSF/1 return a nil authenticator
920 		 * list to indicate RPCAUTH_UNIX.
921 		 */
922 		if (!authfnd && (authcnt > 0 || np->auth != RPCAUTH_UNIX))
923 			np->stat = EAUTH;
924 		return (1);
925 	};
926 	return (0);
927 }
928 
929 void
930 usage()
931 {
932 	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n",
933 "usage: mount_nfs [-23bcdiLlNPsTU] [-a maxreadahead] [-D deadthresh]",
934 "                 [-g maxgroups] [-I readdirsize] [-o options] [-R retrycnt]",
935 "                 [-r readsize] [-t timeout] [-w writesize] [-x retrans]",
936 "                 rhost:path node");
937 	exit(1);
938 }
939