xref: /freebsd/sbin/mount_nfs/mount_nfs.c (revision d056fa046c6a91b90cd98165face0e42a33a5173)
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 
53 #include <rpc/rpc.h>
54 #include <rpc/pmap_clnt.h>
55 #include <rpc/pmap_prot.h>
56 
57 #include <nfs/rpcv2.h>
58 #include <nfs/nfsproto.h>
59 #include <nfsclient/nfs.h>
60 #include <nfsclient/nfsargs.h>
61 
62 #include <arpa/inet.h>
63 
64 #include <ctype.h>
65 #include <err.h>
66 #include <errno.h>
67 #include <fcntl.h>
68 #include <netdb.h>
69 #include <stdio.h>
70 #include <stdlib.h>
71 #include <string.h>
72 #include <strings.h>
73 #include <sysexits.h>
74 #include <unistd.h>
75 
76 #include "mntopts.h"
77 #include "mounttab.h"
78 
79 #define	ALTF_BG		0x1
80 #define ALTF_NOCONN	0x2
81 #define ALTF_DUMBTIMR	0x4
82 #define ALTF_INTR	0x8
83 #define ALTF_NFSV3	0x20
84 #define ALTF_RDIRPLUS	0x40
85 #define ALTF_MNTUDP	0x80
86 #define ALTF_RESVPORT	0x100
87 #define ALTF_SEQPACKET	0x200
88 #define ALTF_SOFT	0x800
89 #define ALTF_TCP	0x1000
90 #define ALTF_PORT	0x2000
91 #define ALTF_NFSV2	0x4000
92 #define ALTF_ACREGMIN	0x8000
93 #define ALTF_ACREGMAX	0x10000
94 #define ALTF_ACDIRMIN	0x20000
95 #define ALTF_ACDIRMAX	0x40000
96 #define ALTF_NOLOCKD	0x80000
97 #define ALTF_NOINET4	0x100000
98 #define ALTF_NOINET6	0x200000
99 
100 struct mntopt mopts[] = {
101 	MOPT_STDOPTS,
102 	MOPT_FORCE,
103 	MOPT_UPDATE,
104 	MOPT_ASYNC,
105 	{ "bg", 0, ALTF_BG, 1 },
106 	{ "conn", 1, ALTF_NOCONN, 1 },
107 	{ "dumbtimer", 0, ALTF_DUMBTIMR, 1 },
108 	{ "intr", 0, ALTF_INTR, 1 },
109 	{ "nfsv3", 0, ALTF_NFSV3, 1 },
110 	{ "rdirplus", 0, ALTF_RDIRPLUS, 1 },
111 	{ "mntudp", 0, ALTF_MNTUDP, 1 },
112 	{ "resvport", 0, ALTF_RESVPORT, 1 },
113 	{ "soft", 0, ALTF_SOFT, 1 },
114 	{ "tcp", 0, ALTF_TCP, 1 },
115 	{ "port=", 0, ALTF_PORT, 1 },
116 	{ "nfsv2", 0, ALTF_NFSV2, 1 },
117 	{ "acregmin=", 0, ALTF_ACREGMIN, 1 },
118 	{ "acregmax=", 0, ALTF_ACREGMAX, 1 },
119 	{ "acdirmin=", 0, ALTF_ACDIRMIN, 1 },
120 	{ "acdirmax=", 0, ALTF_ACDIRMAX, 1 },
121 	{ "lockd", 1, ALTF_NOLOCKD, 1 },
122 	{ "inet4", 1, ALTF_NOINET4, 1 },
123 	{ "inet6", 1, ALTF_NOINET6, 1 },
124 	MOPT_END
125 };
126 
127 struct nfs_args nfsdefargs = {
128 	NFS_ARGSVERSION,
129 	NULL,
130 	sizeof (struct sockaddr_in),
131 	SOCK_DGRAM,
132 	0,
133 	NULL,
134 	0,
135 	NFSMNT_RESVPORT,
136 	NFS_WSIZE,
137 	NFS_RSIZE,
138 	NFS_READDIRSIZE,
139 	10,
140 	NFS_RETRANS,
141 	NFS_MAXGRPS,
142 	NFS_DEFRAHEAD,
143 	0,			/* was: NQ_DEFLEASE */
144 	NFS_MAXDEADTHRESH,	/* was: NQ_DEADTHRESH */
145 	NULL,
146 	/* args version 4 */
147 	NFS_MINATTRTIMO,
148 	NFS_MAXATTRTIMO,
149 	NFS_MINDIRATTRTIMO,
150 	NFS_MAXDIRATTRTIMO,
151 };
152 
153 /* Table for af,sotype -> netid conversions. */
154 struct nc_protos {
155 	char *netid;
156 	int af;
157 	int sotype;
158 } nc_protos[] = {
159 	{"udp",		AF_INET,	SOCK_DGRAM},
160 	{"tcp",		AF_INET,	SOCK_STREAM},
161 	{"udp6",	AF_INET6,	SOCK_DGRAM},
162 	{"tcp6",	AF_INET6,	SOCK_STREAM},
163 	{NULL}
164 };
165 
166 struct nfhret {
167 	u_long		stat;
168 	long		vers;
169 	long		auth;
170 	long		fhsize;
171 	u_char		nfh[NFSX_V3FHMAX];
172 };
173 #define	BGRND	1
174 #define	ISBGRND	2
175 #define	OF_NOINET4	4
176 #define	OF_NOINET6	8
177 int retrycnt = -1;
178 int opflags = 0;
179 int nfsproto = IPPROTO_UDP;
180 int mnttcp_ok = 1;
181 char *portspec = NULL;	/* Server nfs port; NULL means look up via rpcbind. */
182 enum mountmode {
183 	ANY,
184 	V2,
185 	V3
186 } mountmode = ANY;
187 
188 /* Return codes for nfs_tryproto. */
189 enum tryret {
190 	TRYRET_SUCCESS,
191 	TRYRET_TIMEOUT,		/* No response received. */
192 	TRYRET_REMOTEERR,	/* Error received from remote server. */
193 	TRYRET_LOCALERR		/* Local failure. */
194 };
195 
196 int	getnfsargs(char *, struct nfs_args *);
197 /* void	set_rpc_maxgrouplist(int); */
198 struct netconfig *getnetconf_cached(const char *netid);
199 char	*netidbytype(int af, int sotype);
200 void	usage(void) __dead2;
201 int	xdr_dir(XDR *, char *);
202 int	xdr_fh(XDR *, struct nfhret *);
203 enum tryret nfs_tryproto(struct nfs_args *nfsargsp, struct addrinfo *ai,
204     char *hostp, char *spec, char **errstr);
205 enum tryret returncode(enum clnt_stat stat, struct rpc_err *rpcerr);
206 
207 /*
208  * Used to set mount flags with getmntopts.  Call with dir=TRUE to
209  * initialize altflags from the current mount flags.  Call with
210  * dir=FALSE to update mount flags with the new value of altflags after
211  * the call to getmntopts.
212  */
213 static void
214 set_flags(int* altflags, int* nfsflags, int dir)
215 {
216 #define F2(af, nf)					\
217 	if (dir) {					\
218 		if (*nfsflags & NFSMNT_##nf)		\
219 			*altflags |= ALTF_##af;		\
220 		else					\
221 			*altflags &= ~ALTF_##af;	\
222 	} else {					\
223 		if (*altflags & ALTF_##af)		\
224 			*nfsflags |= NFSMNT_##nf;	\
225 		else					\
226 			*nfsflags &= ~NFSMNT_##nf;	\
227 	}
228 #define F(f)	F2(f,f)
229 
230 	F(NOCONN);
231 	F(DUMBTIMR);
232 	F2(INTR, INT);
233 	F(RDIRPLUS);
234 	F(RESVPORT);
235 	F(SOFT);
236 	F(ACREGMIN);
237 	F(ACREGMAX);
238 	F(ACDIRMIN);
239 	F(ACDIRMAX);
240 	F(NOLOCKD);
241 
242 #undef F
243 #undef F2
244 }
245 
246 int
247 main(int argc, char *argv[])
248 {
249 	int c;
250 	struct nfs_args *nfsargsp;
251 	struct nfs_args nfsargs;
252 	int mntflags, altflags, num;
253 	char *name, *p, *spec;
254 	char mntpath[MAXPATHLEN];
255 
256 	mntflags = 0;
257 	altflags = 0;
258 	nfsargs = nfsdefargs;
259 	nfsargsp = &nfsargs;
260 	while ((c = getopt(argc, argv,
261 	    "23a:bcdD:g:I:iLlNo:PR:r:sTt:w:x:U")) != -1)
262 		switch (c) {
263 		case '2':
264 			mountmode = V2;
265 			break;
266 		case '3':
267 			mountmode = V3;
268 			break;
269 		case 'a':
270 			num = strtol(optarg, &p, 10);
271 			if (*p || num < 0)
272 				errx(1, "illegal -a value -- %s", optarg);
273 			nfsargsp->readahead = num;
274 			nfsargsp->flags |= NFSMNT_READAHEAD;
275 			break;
276 		case 'b':
277 			opflags |= BGRND;
278 			break;
279 		case 'c':
280 			nfsargsp->flags |= NFSMNT_NOCONN;
281 			break;
282 		case 'D':
283 			num = strtol(optarg, &p, 10);
284 			if (*p || num <= 0)
285 				errx(1, "illegal -D value -- %s", optarg);
286 			nfsargsp->deadthresh = num;
287 			nfsargsp->flags |= NFSMNT_DEADTHRESH;
288 			break;
289 		case 'd':
290 			nfsargsp->flags |= NFSMNT_DUMBTIMR;
291 			break;
292 #if 0 /* XXXX */
293 		case 'g':
294 			num = strtol(optarg, &p, 10);
295 			if (*p || num <= 0)
296 				errx(1, "illegal -g value -- %s", optarg);
297 			set_rpc_maxgrouplist(num);
298 			nfsargsp->maxgrouplist = num;
299 			nfsargsp->flags |= NFSMNT_MAXGRPS;
300 			break;
301 #endif
302 		case 'I':
303 			num = strtol(optarg, &p, 10);
304 			if (*p || num <= 0)
305 				errx(1, "illegal -I value -- %s", optarg);
306 			nfsargsp->readdirsize = num;
307 			nfsargsp->flags |= NFSMNT_READDIRSIZE;
308 			break;
309 		case 'i':
310 			nfsargsp->flags |= NFSMNT_INT;
311 			break;
312 		case 'L':
313 			nfsargsp->flags |= NFSMNT_NOLOCKD;
314 			break;
315 		case 'l':
316 			nfsargsp->flags |= NFSMNT_RDIRPLUS;
317 			break;
318 		case 'N':
319 			nfsargsp->flags &= ~NFSMNT_RESVPORT;
320 			break;
321 		case 'o':
322 			altflags = 0;
323 			set_flags(&altflags, &nfsargsp->flags, TRUE);
324 			if (mountmode == V2)
325 				altflags |= ALTF_NFSV2;
326 			else if (mountmode == V3)
327 				altflags |= ALTF_NFSV3;
328 			getmntopts(optarg, mopts, &mntflags, &altflags);
329 			set_flags(&altflags, &nfsargsp->flags, FALSE);
330 			/*
331 			 * Handle altflags which don't map directly to
332 			 * mount flags.
333 			 */
334 			if (altflags & ALTF_BG)
335 				opflags |= BGRND;
336 			if (altflags & ALTF_NOINET4)
337 				opflags |= OF_NOINET4;
338 			if (altflags & ALTF_NOINET6)
339 				opflags |= OF_NOINET6;
340 			if (altflags & ALTF_MNTUDP)
341 				mnttcp_ok = 0;
342 			if (altflags & ALTF_TCP) {
343 				nfsargsp->sotype = SOCK_STREAM;
344 				nfsproto = IPPROTO_TCP;
345 			}
346 			if (altflags & ALTF_PORT) {
347 				/*
348 				 * XXX Converting from a string to an int
349 				 * and back again is silly, and we should
350 				 * allow /etc/services names.
351 				 */
352 				p = strstr(optarg, "port=");
353 				if (p) {
354 					asprintf(&portspec, "%d",
355 					    atoi(p + 5));
356 					if (portspec == NULL)
357 						err(1, "asprintf");
358 				}
359 			}
360 			mountmode = ANY;
361 			if (altflags & ALTF_NFSV2)
362 				mountmode = V2;
363 			if (altflags & ALTF_NFSV3)
364 				mountmode = V3;
365 			if (altflags & ALTF_ACREGMIN) {
366 				p = strstr(optarg, "acregmin=");
367 				if (p)
368 					nfsargsp->acregmin = atoi(p + 9);
369 			}
370 			if (altflags & ALTF_ACREGMAX) {
371 				p = strstr(optarg, "acregmax=");
372 				if (p)
373 					nfsargsp->acregmax = atoi(p + 9);
374 			}
375 			if (altflags & ALTF_ACDIRMIN) {
376 				p = strstr(optarg, "acdirmin=");
377 				if (p)
378 					nfsargsp->acdirmin = atoi(p + 9);
379 			}
380 			if (altflags & ALTF_ACDIRMAX) {
381 				p = strstr(optarg, "acdirmax=");
382 				if (p)
383 					nfsargsp->acdirmax = atoi(p + 9);
384 			}
385 			break;
386 		case 'P':
387 			/* obsolete for NFSMNT_RESVPORT, now default */
388 			break;
389 		case 'R':
390 			num = strtol(optarg, &p, 10);
391 			if (*p || num < 0)
392 				errx(1, "illegal -R value -- %s", optarg);
393 			retrycnt = num;
394 			break;
395 		case 'r':
396 			num = strtol(optarg, &p, 10);
397 			if (*p || num <= 0)
398 				errx(1, "illegal -r value -- %s", optarg);
399 			nfsargsp->rsize = num;
400 			nfsargsp->flags |= NFSMNT_RSIZE;
401 			break;
402 		case 's':
403 			nfsargsp->flags |= NFSMNT_SOFT;
404 			break;
405 		case 'T':
406 			nfsargsp->sotype = SOCK_STREAM;
407 			nfsproto = IPPROTO_TCP;
408 			break;
409 		case 't':
410 			num = strtol(optarg, &p, 10);
411 			if (*p || num <= 0)
412 				errx(1, "illegal -t value -- %s", optarg);
413 			nfsargsp->timeo = num;
414 			nfsargsp->flags |= NFSMNT_TIMEO;
415 			break;
416 		case 'w':
417 			num = strtol(optarg, &p, 10);
418 			if (*p || num <= 0)
419 				errx(1, "illegal -w value -- %s", optarg);
420 			nfsargsp->wsize = num;
421 			nfsargsp->flags |= NFSMNT_WSIZE;
422 			break;
423 		case 'x':
424 			num = strtol(optarg, &p, 10);
425 			if (*p || num <= 0)
426 				errx(1, "illegal -x value -- %s", optarg);
427 			nfsargsp->retrans = num;
428 			nfsargsp->flags |= NFSMNT_RETRANS;
429 			break;
430 		case 'U':
431 			mnttcp_ok = 0;
432 			break;
433 		default:
434 			usage();
435 			break;
436 		}
437 	argc -= optind;
438 	argv += optind;
439 
440 	if (argc != 2) {
441 		usage();
442 		/* NOTREACHED */
443 	}
444 
445 	spec = *argv++;
446 	name = *argv;
447 
448 	if (retrycnt == -1)
449 		/* The default is to keep retrying forever. */
450 		retrycnt = 0;
451 	if (!getnfsargs(spec, nfsargsp))
452 		exit(1);
453 
454 	/* resolve the mountpoint with realpath(3) */
455 	(void)checkpath(name, mntpath);
456 
457 	if (mount("nfs", mntpath, mntflags, nfsargsp))
458 		err(1, "%s", mntpath);
459 
460 	exit(0);
461 }
462 
463 int
464 getnfsargs(char *spec, struct nfs_args *nfsargsp)
465 {
466 	struct addrinfo hints, *ai_nfs, *ai;
467 	enum tryret ret;
468 	int ecode, speclen, remoteerr;
469 	char *hostp, *delimp, *errstr;
470 	size_t len;
471 	static char nam[MNAMELEN + 1];
472 
473 	if ((delimp = strrchr(spec, ':')) != NULL) {
474 		hostp = spec;
475 		spec = delimp + 1;
476 	} else if ((delimp = strrchr(spec, '@')) != NULL) {
477 		warnx("path@server syntax is deprecated, use server:path");
478 		hostp = delimp + 1;
479 	} else {
480 		warnx("no <host>:<dirpath> nfs-name");
481 		return (0);
482 	}
483 	*delimp = '\0';
484 
485 	/*
486 	 * If there has been a trailing slash at mounttime it seems
487 	 * that some mountd implementations fail to remove the mount
488 	 * entries from their mountlist while unmounting.
489 	 */
490 	for (speclen = strlen(spec);
491 		speclen > 1 && spec[speclen - 1] == '/';
492 		speclen--)
493 		spec[speclen - 1] = '\0';
494 	if (strlen(hostp) + strlen(spec) + 1 > MNAMELEN) {
495 		warnx("%s:%s: %s", hostp, spec, strerror(ENAMETOOLONG));
496 		return (0);
497 	}
498 	/* Make both '@' and ':' notations equal */
499 	if (*hostp != '\0') {
500 		len = strlen(hostp);
501 		memmove(nam, hostp, len);
502 		nam[len] = ':';
503 		memmove(nam + len + 1, spec, speclen);
504 		nam[len + speclen + 1] = '\0';
505 	}
506 
507 	/*
508 	 * Handle an internet host address.
509 	 */
510 	memset(&hints, 0, sizeof hints);
511 	hints.ai_flags = AI_NUMERICHOST;
512 	hints.ai_socktype = nfsargsp->sotype;
513 	if (getaddrinfo(hostp, portspec, &hints, &ai_nfs) != 0) {
514 		hints.ai_flags = 0;
515 		if ((ecode = getaddrinfo(hostp, portspec, &hints, &ai_nfs))
516 		    != 0) {
517 			if (portspec == NULL)
518 				errx(1, "%s: %s", hostp, gai_strerror(ecode));
519 			else
520 				errx(1, "%s:%s: %s", hostp, portspec,
521 				    gai_strerror(ecode));
522 			return (0);
523 		}
524 	}
525 
526 	ret = TRYRET_LOCALERR;
527 	for (;;) {
528 		/*
529 		 * Try each entry returned by getaddrinfo(). Note the
530 		 * occurence of remote errors by setting `remoteerr'.
531 		 */
532 		remoteerr = 0;
533 		for (ai = ai_nfs; ai != NULL; ai = ai->ai_next) {
534 			if ((ai->ai_family == AF_INET6) &&
535 			    (opflags & OF_NOINET6))
536 				continue;
537 			if ((ai->ai_family == AF_INET) &&
538 			    (opflags & OF_NOINET4))
539 				continue;
540 			ret = nfs_tryproto(nfsargsp, ai, hostp, spec, &errstr);
541 			if (ret == TRYRET_SUCCESS)
542 				break;
543 			if (ret != TRYRET_LOCALERR)
544 				remoteerr = 1;
545 			if ((opflags & ISBGRND) == 0)
546 				fprintf(stderr, "%s\n", errstr);
547 		}
548 		if (ret == TRYRET_SUCCESS)
549 			break;
550 
551 		/* Exit if all errors were local. */
552 		if (!remoteerr)
553 			exit(1);
554 
555 		/*
556 		 * If retrycnt == 0, we are to keep retrying forever.
557 		 * Otherwise decrement it, and exit if it hits zero.
558 		 */
559 		if (retrycnt != 0 && --retrycnt == 0)
560 			exit(1);
561 
562 		if ((opflags & (BGRND | ISBGRND)) == BGRND) {
563 			warnx("Cannot immediately mount %s:%s, backgrounding",
564 			    hostp, spec);
565 			opflags |= ISBGRND;
566 			if (daemon(0, 0) != 0)
567 				err(1, "daemon");
568 		}
569 		sleep(60);
570 	}
571 	freeaddrinfo(ai_nfs);
572 	nfsargsp->hostname = nam;
573 	/* Add mounted file system to PATH_MOUNTTAB */
574 	if (!add_mtab(hostp, spec))
575 		warnx("can't update %s for %s:%s", PATH_MOUNTTAB, hostp, spec);
576 	return (1);
577 }
578 
579 /*
580  * Try to set up the NFS arguments according to the address
581  * family, protocol (and possibly port) specified in `ai'.
582  *
583  * Returns TRYRET_SUCCESS if successful, or:
584  *   TRYRET_TIMEOUT		The server did not respond.
585  *   TRYRET_REMOTEERR		The server reported an error.
586  *   TRYRET_LOCALERR		Local failure.
587  *
588  * In all error cases, *errstr will be set to a statically-allocated string
589  * describing the error.
590  */
591 enum tryret
592 nfs_tryproto(struct nfs_args *nfsargsp, struct addrinfo *ai, char *hostp,
593     char *spec, char **errstr)
594 {
595 	static char errbuf[256];
596 	struct sockaddr_storage nfs_ss;
597 	struct netbuf nfs_nb;
598 	struct nfhret nfhret;
599 	struct timeval try;
600 	struct rpc_err rpcerr;
601 	CLIENT *clp;
602 	struct netconfig *nconf, *nconf_mnt;
603 	char *netid, *netid_mnt;
604 	int doconnect, nfsvers, mntvers;
605 	enum clnt_stat stat;
606 	enum mountmode trymntmode;
607 
608 	trymntmode = mountmode;
609 	errbuf[0] = '\0';
610 	*errstr = errbuf;
611 
612 	if ((netid = netidbytype(ai->ai_family, nfsargsp->sotype)) == NULL) {
613 		snprintf(errbuf, sizeof errbuf,
614 		    "af %d sotype %d not supported", ai->ai_family,
615 		    nfsargsp->sotype);
616 		return (TRYRET_LOCALERR);
617 	}
618 	if ((nconf = getnetconf_cached(netid)) == NULL) {
619 		snprintf(errbuf, sizeof errbuf, "%s: %s", netid, nc_sperror());
620 		return (TRYRET_LOCALERR);
621 	}
622 	/* The RPCPROG_MNT netid may be different. */
623 	if (mnttcp_ok) {
624 		netid_mnt = netid;
625 		nconf_mnt = nconf;
626 	} else {
627 		if ((netid_mnt = netidbytype(ai->ai_family, SOCK_DGRAM))
628 		     == NULL) {
629 			snprintf(errbuf, sizeof errbuf,
630 			    "af %d sotype SOCK_DGRAM not supported",
631 			     ai->ai_family);
632 			return (TRYRET_LOCALERR);
633 		}
634 		if ((nconf_mnt = getnetconf_cached(netid_mnt)) == NULL) {
635 			snprintf(errbuf, sizeof errbuf, "%s: %s", netid_mnt,
636 			    nc_sperror());
637 			return (TRYRET_LOCALERR);
638 		}
639 	}
640 
641 tryagain:
642 	if (trymntmode == V2) {
643 		nfsvers = 2;
644 		mntvers = 1;
645 	} else {
646 		nfsvers = 3;
647 		mntvers = 3;
648 	}
649 
650 	if (portspec != NULL) {
651 		/* `ai' contains the complete nfsd sockaddr. */
652 		nfs_nb.buf = ai->ai_addr;
653 		nfs_nb.len = nfs_nb.maxlen = ai->ai_addrlen;
654 	} else {
655 		/* Ask the remote rpcbind. */
656 		nfs_nb.buf = &nfs_ss;
657 		nfs_nb.len = nfs_nb.maxlen = sizeof nfs_ss;
658 
659 		if (!rpcb_getaddr(RPCPROG_NFS, nfsvers, nconf, &nfs_nb,
660 		    hostp)) {
661 			if (rpc_createerr.cf_stat == RPC_PROGVERSMISMATCH &&
662 			    trymntmode == ANY) {
663 				trymntmode = V2;
664 				goto tryagain;
665 			}
666 			snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s",
667 			    netid, hostp, spec,
668 			    clnt_spcreateerror("RPCPROG_NFS"));
669 			return (returncode(rpc_createerr.cf_stat,
670 			    &rpc_createerr.cf_error));
671 		}
672 	}
673 
674 	/* Check that the server (nfsd) responds on the port we have chosen. */
675 	clp = clnt_tli_create(RPC_ANYFD, nconf, &nfs_nb, RPCPROG_NFS, nfsvers,
676 	    0, 0);
677 	if (clp == NULL) {
678 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid,
679 		    hostp, spec, clnt_spcreateerror("nfsd: RPCPROG_NFS"));
680 		return (returncode(rpc_createerr.cf_stat,
681 		    &rpc_createerr.cf_error));
682 	}
683 	if (nfsargsp->sotype == SOCK_DGRAM &&
684 	    !(nfsargsp->flags & NFSMNT_NOCONN)) {
685 		/*
686 		 * Use connect(), to match what the kernel does. This
687 		 * catches cases where the server responds from the
688 		 * wrong source address.
689 		 */
690 		doconnect = 1;
691 		if (!clnt_control(clp, CLSET_CONNECT, (char *)&doconnect)) {
692 			clnt_destroy(clp);
693 			snprintf(errbuf, sizeof errbuf,
694 			    "[%s] %s:%s: CLSET_CONNECT failed", netid, hostp,
695 			    spec);
696 			return (TRYRET_LOCALERR);
697 		}
698 	}
699 
700 	try.tv_sec = 10;
701 	try.tv_usec = 0;
702 	stat = clnt_call(clp, NFSPROC_NULL, (xdrproc_t)xdr_void, NULL,
703 			 (xdrproc_t)xdr_void, NULL,
704 	    try);
705 	if (stat != RPC_SUCCESS) {
706 		if (stat == RPC_PROGVERSMISMATCH && trymntmode == ANY) {
707 			clnt_destroy(clp);
708 			trymntmode = V2;
709 			goto tryagain;
710 		}
711 		clnt_geterr(clp, &rpcerr);
712 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid,
713 		    hostp, spec, clnt_sperror(clp, "NFSPROC_NULL"));
714 		clnt_destroy(clp);
715 		return (returncode(stat, &rpcerr));
716 	}
717 	clnt_destroy(clp);
718 
719 	/* Send the RPCMNT_MOUNT RPC to get the root filehandle. */
720 	try.tv_sec = 10;
721 	try.tv_usec = 0;
722 	clp = clnt_tp_create(hostp, RPCPROG_MNT, mntvers, nconf_mnt);
723 	if (clp == NULL) {
724 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid_mnt,
725 		    hostp, spec, clnt_spcreateerror("RPCMNT: clnt_create"));
726 		return (returncode(rpc_createerr.cf_stat,
727 		    &rpc_createerr.cf_error));
728 	}
729 	clp->cl_auth = authsys_create_default();
730 	nfhret.auth = RPCAUTH_UNIX;
731 	nfhret.vers = mntvers;
732 	stat = clnt_call(clp, RPCMNT_MOUNT, (xdrproc_t)xdr_dir, spec,
733 			 (xdrproc_t)xdr_fh, &nfhret,
734 	    try);
735 	auth_destroy(clp->cl_auth);
736 	if (stat != RPC_SUCCESS) {
737 		if (stat == RPC_PROGVERSMISMATCH && trymntmode == ANY) {
738 			clnt_destroy(clp);
739 			trymntmode = V2;
740 			goto tryagain;
741 		}
742 		clnt_geterr(clp, &rpcerr);
743 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid_mnt,
744 		    hostp, spec, clnt_sperror(clp, "RPCPROG_MNT"));
745 		clnt_destroy(clp);
746 		return (returncode(stat, &rpcerr));
747 	}
748 	clnt_destroy(clp);
749 
750 	if (nfhret.stat != 0) {
751 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid_mnt,
752 		    hostp, spec, strerror(nfhret.stat));
753 		return (TRYRET_REMOTEERR);
754 	}
755 
756 	/*
757 	 * Store the filehandle and server address in nfsargsp, making
758 	 * sure to copy any locally allocated structures.
759 	 */
760 	nfsargsp->addrlen = nfs_nb.len;
761 	nfsargsp->addr = malloc(nfsargsp->addrlen);
762 	nfsargsp->fhsize = nfhret.fhsize;
763 	nfsargsp->fh = malloc(nfsargsp->fhsize);
764 	if (nfsargsp->addr == NULL || nfsargsp->fh == NULL)
765 		err(1, "malloc");
766 	bcopy(nfs_nb.buf, nfsargsp->addr, nfsargsp->addrlen);
767 	bcopy(nfhret.nfh, nfsargsp->fh, nfsargsp->fhsize);
768 
769 	if (nfsvers == 3)
770 		nfsargsp->flags |= NFSMNT_NFSV3;
771 	else
772 		nfsargsp->flags &= ~NFSMNT_NFSV3;
773 
774 	return (TRYRET_SUCCESS);
775 }
776 
777 
778 /*
779  * Catagorise a RPC return status and error into an `enum tryret'
780  * return code.
781  */
782 enum tryret
783 returncode(enum clnt_stat stat, struct rpc_err *rpcerr)
784 {
785 	switch (stat) {
786 	case RPC_TIMEDOUT:
787 		return (TRYRET_TIMEOUT);
788 	case RPC_PMAPFAILURE:
789 	case RPC_PROGNOTREGISTERED:
790 	case RPC_PROGVERSMISMATCH:
791 	/* XXX, these can be local or remote. */
792 	case RPC_CANTSEND:
793 	case RPC_CANTRECV:
794 		return (TRYRET_REMOTEERR);
795 	case RPC_SYSTEMERROR:
796 		switch (rpcerr->re_errno) {
797 		case ETIMEDOUT:
798 			return (TRYRET_TIMEOUT);
799 		case ENOMEM:
800 			break;
801 		default:
802 			return (TRYRET_REMOTEERR);
803 		}
804 		/* FALLTHROUGH */
805 	default:
806 		break;
807 	}
808 	return (TRYRET_LOCALERR);
809 }
810 
811 /*
812  * Look up a netid based on an address family and socket type.
813  * `af' is the address family, and `sotype' is SOCK_DGRAM or SOCK_STREAM.
814  *
815  * XXX there should be a library function for this.
816  */
817 char *
818 netidbytype(int af, int sotype)
819 {
820 	struct nc_protos *p;
821 
822 	for (p = nc_protos; p->netid != NULL; p++) {
823 		if (af != p->af || sotype != p->sotype)
824 			continue;
825 		return (p->netid);
826 	}
827 	return (NULL);
828 }
829 
830 /*
831  * Look up a netconfig entry based on a netid, and cache the result so
832  * that we don't need to remember to call freenetconfigent().
833  *
834  * Otherwise it behaves just like getnetconfigent(), so nc_*error()
835  * work on failure.
836  */
837 struct netconfig *
838 getnetconf_cached(const char *netid)
839 {
840 	static struct nc_entry {
841 		struct netconfig *nconf;
842 		struct nc_entry *next;
843 	} *head;
844 	struct nc_entry *p;
845 	struct netconfig *nconf;
846 
847 	for (p = head; p != NULL; p = p->next)
848 		if (strcmp(netid, p->nconf->nc_netid) == 0)
849 			return (p->nconf);
850 
851 	if ((nconf = getnetconfigent(netid)) == NULL)
852 		return (NULL);
853 	if ((p = malloc(sizeof(*p))) == NULL)
854 		err(1, "malloc");
855 	p->nconf = nconf;
856 	p->next = head;
857 	head = p;
858 
859 	return (p->nconf);
860 }
861 
862 /*
863  * xdr routines for mount rpc's
864  */
865 int
866 xdr_dir(XDR *xdrsp, char *dirp)
867 {
868 	return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN));
869 }
870 
871 int
872 xdr_fh(XDR *xdrsp, struct nfhret *np)
873 {
874 	int i;
875 	long auth, authcnt, authfnd = 0;
876 
877 	if (!xdr_u_long(xdrsp, &np->stat))
878 		return (0);
879 	if (np->stat)
880 		return (1);
881 	switch (np->vers) {
882 	case 1:
883 		np->fhsize = NFSX_V2FH;
884 		return (xdr_opaque(xdrsp, (caddr_t)np->nfh, NFSX_V2FH));
885 	case 3:
886 		if (!xdr_long(xdrsp, &np->fhsize))
887 			return (0);
888 		if (np->fhsize <= 0 || np->fhsize > NFSX_V3FHMAX)
889 			return (0);
890 		if (!xdr_opaque(xdrsp, (caddr_t)np->nfh, np->fhsize))
891 			return (0);
892 		if (!xdr_long(xdrsp, &authcnt))
893 			return (0);
894 		for (i = 0; i < authcnt; i++) {
895 			if (!xdr_long(xdrsp, &auth))
896 				return (0);
897 			if (auth == np->auth)
898 				authfnd++;
899 		}
900 		/*
901 		 * Some servers, such as DEC's OSF/1 return a nil authenticator
902 		 * list to indicate RPCAUTH_UNIX.
903 		 */
904 		if (!authfnd && (authcnt > 0 || np->auth != RPCAUTH_UNIX))
905 			np->stat = EAUTH;
906 		return (1);
907 	};
908 	return (0);
909 }
910 
911 void
912 usage()
913 {
914 	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n",
915 "usage: mount_nfs [-23bcdiLlNPsTU] [-a maxreadahead] [-D deadthresh]",
916 "                 [-g maxgroups] [-I readdirsize] [-o options] [-R retrycnt]",
917 "                 [-r readsize] [-t timeout] [-w writesize] [-x retrans]",
918 "                 rhost:path node");
919 	exit(1);
920 }
921