xref: /dragonfly/sbin/mount_nfs/mount_nfs.c (revision 2e3ed54d)
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  * 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  * @(#) Copyright (c) 1992, 1993, 1994 The Regents of the University of California.  All rights reserved.
37  * @(#)mount_nfs.c	8.11 (Berkeley) 5/4/95
38  * $FreeBSD: src/sbin/mount_nfs/mount_nfs.c,v 1.36.2.6 2003/05/13 14:45:40 trhodes Exp $
39  * $DragonFly: src/sbin/mount_nfs/mount_nfs.c,v 1.11 2005/11/06 12:34:21 swildner Exp $
40  */
41 
42 #include <sys/param.h>
43 #include <sys/mount.h>
44 #include <sys/stat.h>
45 #include <sys/syslog.h>
46 
47 #include <rpc/rpc.h>
48 #include <rpc/pmap_clnt.h>
49 #include <rpc/pmap_prot.h>
50 
51 #include <vfs/nfs/rpcv2.h>
52 #include <vfs/nfs/nfsproto.h>
53 #include <vfs/nfs/nfs.h>
54 #include <vfs/nfs/nqnfs.h>
55 
56 #include <arpa/inet.h>
57 
58 #include <ctype.h>
59 #include <err.h>
60 #include <errno.h>
61 #include <netdb.h>
62 #include <stdio.h>
63 #include <stdlib.h>
64 #include <strings.h>
65 #include <sysexits.h>
66 #include <unistd.h>
67 #include <resolv.h>
68 
69 #include "mntopts.h"
70 #include "mounttab.h"
71 
72 #define	ALTF_BG		0x1
73 #define ALTF_NOCONN	0x2
74 #define ALTF_DUMBTIMR	0x4
75 #define ALTF_INTR	0x8
76 #define ALTF_KERB	0x10
77 #define ALTF_NFSV3	0x20
78 #define ALTF_RDIRPLUS	0x40
79 #define	ALTF_MNTUDP	0x80
80 #define ALTF_RESVPORT	0x100
81 #define ALTF_SEQPACKET	0x200
82 #define ALTF_NQNFS	0x400
83 #define ALTF_SOFT	0x800
84 #define ALTF_TCP	0x1000
85 #define ALTF_PORT	0x2000
86 #define ALTF_NFSV2	0x4000
87 #define ALTF_ACREGMIN	0x8000
88 #define ALTF_ACREGMAX	0x10000
89 #define ALTF_ACDIRMIN	0x20000
90 #define ALTF_ACDIRMAX	0x40000
91 
92 struct mntopt mopts[] = {
93 	MOPT_STDOPTS,
94 	MOPT_FORCE,
95 	MOPT_UPDATE,
96 	MOPT_ASYNC,
97 	{ "bg", 0, ALTF_BG, 1 },
98 	{ "conn", 1, ALTF_NOCONN, 1 },
99 	{ "dumbtimer", 0, ALTF_DUMBTIMR, 1 },
100 	{ "intr", 0, ALTF_INTR, 1 },
101 #ifdef NFSKERB
102 	{ "kerb", 0, ALTF_KERB, 1 },
103 #endif
104 	{ "nfsv3", 0, ALTF_NFSV3, 1 },
105 	{ "rdirplus", 0, ALTF_RDIRPLUS, 1 },
106 	{ "mntudp", 0, ALTF_MNTUDP, 1 },
107 	{ "resvport", 0, ALTF_RESVPORT, 1 },
108 	{ "nqnfs", 0, ALTF_NQNFS, 1 },
109 	{ "soft", 0, ALTF_SOFT, 1 },
110 	{ "tcp", 0, ALTF_TCP, 1 },
111 	{ "port=", 0, ALTF_PORT, 1 },
112 	{ "nfsv2", 0, ALTF_NFSV2, 1 },
113 	{ "acregmin=", 0, ALTF_ACREGMIN, 1 },
114 	{ "acregmax=", 0, ALTF_ACREGMAX, 1 },
115 	{ "acdirmin=", 0, ALTF_ACDIRMIN, 1 },
116 	{ "acdirmax=", 0, ALTF_ACDIRMAX, 1 },
117 	MOPT_NULL
118 };
119 
120 struct nfs_args nfsdefargs = {
121 	NFS_ARGSVERSION,
122 	(struct sockaddr *)0,
123 	sizeof (struct sockaddr_in),
124 	SOCK_DGRAM,
125 	0,
126 	(u_char *)0,
127 	0,
128 	NFSMNT_RESVPORT,
129 	NFS_WSIZE,
130 	NFS_RSIZE,
131 	NFS_READDIRSIZE,
132 	10,
133 	NFS_RETRANS,
134 	NFS_MAXGRPS,
135 	NFS_DEFRAHEAD,
136 	NQ_DEFLEASE,
137 	NQ_DEADTHRESH,
138 	(char *)0,
139 	/* args version 4 */
140 	NFS_MINATTRTIMO,
141 	NFS_MAXATTRTIMO,
142 	NFS_MINDIRATTRTIMO,
143 	NFS_MAXDIRATTRTIMO,
144 };
145 
146 struct nfhret {
147 	u_long		stat;
148 	long		vers;
149 	long		auth;
150 	long		fhsize;
151 	u_char		nfh[NFSX_V3FHMAX];
152 };
153 
154 #define	BGRND	0x0001
155 #define	ISBGRND	0x0002
156 #define DIDWARN 0x0004
157 
158 int retrycnt = -1;
159 int opflags = 0;
160 int nfsproto = IPPROTO_UDP;
161 int mnttcp_ok = 1;
162 u_short port_no = 0;
163 enum mountmode {
164 	ANY,
165 	V2,
166 	V3
167 } mountmode = ANY;
168 
169 #ifdef NFSKERB
170 char inst[INST_SZ];
171 char realm[REALM_SZ];
172 struct {
173 	u_long		kind;
174 	KTEXT_ST	kt;
175 } ktick;
176 struct nfsrpc_nickverf kverf;
177 struct nfsrpc_fullblock kin, kout;
178 NFSKERBKEY_T kivec;
179 CREDENTIALS kcr;
180 struct timeval ktv;
181 NFSKERBKEYSCHED_T kerb_keysched;
182 #endif
183 
184 /* Return codes for nfs_tryproto. */
185 enum tryret {
186 	TRYRET_SUCCESS,
187 	TRYRET_TIMEOUT,		/* No response received. */
188 	TRYRET_REMOTEERR,	/* Error received from remote server. */
189 	TRYRET_LOCALERR		/* Local failure. */
190 };
191 
192 void	set_rpc_maxgrouplist(int);
193 
194 static int	getnfsargs(char *, struct nfs_args *);
195 static void	usage(void) __dead2;
196 static int	xdr_dir(XDR *, char *);
197 static int	xdr_fh(XDR *, struct nfhret *);
198 static enum tryret
199 		nfs_tryproto(struct nfs_args *, struct sockaddr_in *,
200 			     char *, char *, char **);
201 static enum tryret
202 		returncode(enum clnt_stat, struct rpc_err *);
203 
204 /*
205  * Used to set mount flags with getmntopts.  Call with dir=TRUE to
206  * initialize altflags from the current mount flags.  Call with
207  * dir=FALSE to update mount flags with the new value of altflags after
208  * the call to getmntopts.
209  */
210 static void
211 set_flags(int* altflags, int* nfsflags, int dir)
212 {
213 #define F2(af, nf)					\
214 	if (dir) {					\
215 		if (*nfsflags & NFSMNT_##nf)		\
216 			*altflags |= ALTF_##af;		\
217 		else					\
218 			*altflags &= ~ALTF_##af;	\
219 	} else {					\
220 		if (*altflags & ALTF_##af)		\
221 			*nfsflags |= NFSMNT_##nf;	\
222 		else					\
223 			*nfsflags &= ~NFSMNT_##nf;	\
224 	}
225 #define F(f)	F2(f,f)
226 
227 	F(NOCONN);
228 	F(DUMBTIMR);
229 	F2(INTR, INT);
230 #ifdef NFSKERB
231 	F(KERB);
232 #endif
233 	F(RDIRPLUS);
234 	F(RESVPORT);
235 	F(NQNFS);
236 	F(SOFT);
237 	F(ACREGMIN);
238 	F(ACREGMAX);
239 	F(ACDIRMIN);
240 	F(ACDIRMAX);
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 	struct nfsd_cargs ncd;
253 	int mntflags, altflags, nfssvc_flag, num;
254 	char *name, *p, *spec;
255 	char mntpath[MAXPATHLEN];
256 	struct vfsconf vfc;
257 	int error = 0;
258 #ifdef NFSKERB
259 	uid_t last_ruid;
260 
261 	last_ruid = -1;
262 	strcpy(realm, KRB_REALM);
263 	if (sizeof (struct nfsrpc_nickverf) != RPCX_NICKVERF ||
264 	    sizeof (struct nfsrpc_fullblock) != RPCX_FULLBLOCK ||
265 	    ((char *)&ktick.kt) - ((char *)&ktick) != NFSX_UNSIGNED ||
266 	    ((char *)ktick.kt.dat) - ((char *)&ktick) != 2 * NFSX_UNSIGNED)
267 		fprintf(stderr, "Yikes! NFSKERB structs not packed!!\n");
268 #endif /* NFSKERB */
269 
270 	mntflags = 0;
271 	altflags = 0;
272 	nfsargs = nfsdefargs;
273 	nfsargsp = &nfsargs;
274 	while ((c = getopt(argc, argv,
275 	    "23a:bcdD:g:I:iKL:lm:No:PqR:r:sTt:w:x:U")) != -1)
276 		switch (c) {
277 		case '2':
278 			mountmode = V2;
279 			break;
280 		case '3':
281 			mountmode = V3;
282 			break;
283 		case 'a':
284 			num = strtol(optarg, &p, 10);
285 			if (*p || num < 0)
286 				errx(1, "illegal -a value -- %s", optarg);
287 			nfsargsp->readahead = num;
288 			nfsargsp->flags |= NFSMNT_READAHEAD;
289 			break;
290 		case 'b':
291 			opflags |= BGRND;
292 			break;
293 		case 'c':
294 			nfsargsp->flags |= NFSMNT_NOCONN;
295 			break;
296 		case 'D':
297 			num = strtol(optarg, &p, 10);
298 			if (*p || num <= 0)
299 				errx(1, "illegal -D value -- %s", optarg);
300 			nfsargsp->deadthresh = num;
301 			nfsargsp->flags |= NFSMNT_DEADTHRESH;
302 			break;
303 		case 'd':
304 			nfsargsp->flags |= NFSMNT_DUMBTIMR;
305 			break;
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 		case 'I':
315 			num = strtol(optarg, &p, 10);
316 			if (*p || num <= 0)
317 				errx(1, "illegal -I value -- %s", optarg);
318 			nfsargsp->readdirsize = num;
319 			nfsargsp->flags |= NFSMNT_READDIRSIZE;
320 			break;
321 		case 'i':
322 			nfsargsp->flags |= NFSMNT_INT;
323 			break;
324 #ifdef NFSKERB
325 		case 'K':
326 			nfsargsp->flags |= NFSMNT_KERB;
327 			break;
328 #endif
329 		case 'L':
330 			num = strtol(optarg, &p, 10);
331 			if (*p || num < 2)
332 				errx(1, "illegal -L value -- %s", optarg);
333 			nfsargsp->leaseterm = num;
334 			nfsargsp->flags |= NFSMNT_LEASETERM;
335 			break;
336 		case 'l':
337 			nfsargsp->flags |= NFSMNT_RDIRPLUS;
338 			break;
339 #ifdef NFSKERB
340 		case 'm':
341 			strncpy(realm, optarg, REALM_SZ - 1);
342 			realm[REALM_SZ - 1] = '\0';
343 			break;
344 #endif
345 		case 'N':
346 			nfsargsp->flags &= ~NFSMNT_RESVPORT;
347 			break;
348 		case 'o':
349 			altflags = 0;
350 			set_flags(&altflags, &nfsargsp->flags, TRUE);
351 			if (mountmode == V2)
352 				altflags |= ALTF_NFSV2;
353 			else if (mountmode == V3)
354 				altflags |= ALTF_NFSV3;
355 			getmntopts(optarg, mopts, &mntflags, &altflags);
356 			set_flags(&altflags, &nfsargsp->flags, FALSE);
357 			/*
358 			 * Handle altflags which don't map directly to
359 			 * mount flags.
360 			 */
361 			if(altflags & ALTF_BG)
362 				opflags |= BGRND;
363 			if(altflags & ALTF_MNTUDP)
364 				mnttcp_ok = 0;
365 			if(altflags & ALTF_TCP) {
366 				nfsargsp->sotype = SOCK_STREAM;
367 				nfsproto = IPPROTO_TCP;
368 			}
369 			if(altflags & ALTF_PORT)
370 				port_no = atoi(strstr(optarg, "port=") + 5);
371 			mountmode = ANY;
372 			if(altflags & ALTF_NFSV2)
373 				mountmode = V2;
374 			if(altflags & ALTF_NFSV3)
375 				mountmode = V3;
376 			if(altflags & ALTF_ACREGMIN)
377 				nfsargsp->acregmin = atoi(strstr(optarg,
378 				    "acregmin=") + 9);
379 			if(altflags & ALTF_ACREGMAX)
380 				nfsargsp->acregmax = atoi(strstr(optarg,
381 				    "acregmax=") + 9);
382 			if(altflags & ALTF_ACDIRMIN)
383 				nfsargsp->acdirmin = atoi(strstr(optarg,
384 				    "acdirmin=") + 9);
385 			if(altflags & ALTF_ACDIRMAX)
386 				nfsargsp->acdirmax = atoi(strstr(optarg,
387 				    "acdirmax=") + 9);
388 			break;
389 		case 'P':
390 			/* obsolete for NFSMNT_RESVPORT, now default */
391 			break;
392 		case 'q':
393 			mountmode = V3;
394 			nfsargsp->flags |= NFSMNT_NQNFS;
395 			break;
396 		case 'R':
397 			num = strtol(optarg, &p, 10);
398 			if (*p || num < 0)
399 				errx(1, "illegal -R value -- %s", optarg);
400 			retrycnt = num;
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 			nfsargsp->rsize = num;
407 			nfsargsp->flags |= NFSMNT_RSIZE;
408 			break;
409 		case 's':
410 			nfsargsp->flags |= NFSMNT_SOFT;
411 			break;
412 		case 'T':
413 			nfsargsp->sotype = SOCK_STREAM;
414 			nfsproto = IPPROTO_TCP;
415 			break;
416 		case 't':
417 			num = strtol(optarg, &p, 10);
418 			if (*p || num <= 0)
419 				errx(1, "illegal -t value -- %s", optarg);
420 			nfsargsp->timeo = num;
421 			nfsargsp->flags |= NFSMNT_TIMEO;
422 			break;
423 		case 'w':
424 			num = strtol(optarg, &p, 10);
425 			if (*p || num <= 0)
426 				errx(1, "illegal -w value -- %s", optarg);
427 			nfsargsp->wsize = num;
428 			nfsargsp->flags |= NFSMNT_WSIZE;
429 			break;
430 		case 'x':
431 			num = strtol(optarg, &p, 10);
432 			if (*p || num <= 0)
433 				errx(1, "illegal -x value -- %s", optarg);
434 			nfsargsp->retrans = num;
435 			nfsargsp->flags |= NFSMNT_RETRANS;
436 			break;
437 		case 'U':
438 			mnttcp_ok = 0;
439 			break;
440 		default:
441 			usage();
442 			break;
443 		}
444 	argc -= optind;
445 	argv += optind;
446 
447 	if (argc != 2) {
448 		usage();
449 		/* NOTREACHED */
450 	}
451 
452 	spec = *argv++;
453 	name = *argv;
454 
455 	if (retrycnt == -1)
456 		/* The default is to keep retrying forever. */
457 		retrycnt = 0;
458 	if (!getnfsargs(spec, nfsargsp))
459 		exit(1);
460 
461 	/* resolve the mountpoint with realpath(3) */
462 	checkpath(name, mntpath);
463 
464 	error = getvfsbyname("nfs", &vfc);
465 	if (error && vfsisloadable("nfs")) {
466 		if(vfsload("nfs"))
467 			err(EX_OSERR, "vfsload(nfs)");
468 		endvfsent();	/* clear cache */
469 		error = getvfsbyname("nfs", &vfc);
470 	}
471 	if (error)
472 		errx(EX_OSERR, "nfs filesystem is not available");
473 
474 	if (mount(vfc.vfc_name, mntpath, mntflags, nfsargsp))
475 		err(1, "%s", mntpath);
476 	if (nfsargsp->flags & (NFSMNT_NQNFS | NFSMNT_KERB)) {
477 		if ((opflags & ISBGRND) == 0) {
478 			if (daemon(0, 0) != 0)
479 				err(1, "daemon");
480 		}
481 		openlog("mount_nfs", LOG_PID, LOG_DAEMON);
482 		nfssvc_flag = NFSSVC_MNTD;
483 		ncd.ncd_dirp = mntpath;
484 		while (nfssvc(nfssvc_flag, (caddr_t)&ncd) < 0) {
485 			if (errno != ENEEDAUTH) {
486 				syslog(LOG_ERR, "nfssvc err %m");
487 				continue;
488 			}
489 			nfssvc_flag =
490 			    NFSSVC_MNTD | NFSSVC_GOTAUTH | NFSSVC_AUTHINFAIL;
491 #ifdef NFSKERB
492 			/*
493 			 * Set up as ncd_authuid for the kerberos call.
494 			 * Must set ruid to ncd_authuid and reset the
495 			 * ticket name iff ncd_authuid is not the same
496 			 * as last time, so that the right ticket file
497 			 * is found.
498 			 * Get the Kerberos credential structure so that
499 			 * we have the session key and get a ticket for
500 			 * this uid.
501 			 * For more info see the IETF Draft "Authentication
502 			 * in ONC RPC".
503 			 */
504 			if (ncd.ncd_authuid != last_ruid) {
505 				char buf[512];
506 				sprintf(buf, "%s%d", TKT_ROOT, ncd.ncd_authuid);
507 				krb_set_tkt_string(buf);
508 				last_ruid = ncd.ncd_authuid;
509 			}
510 			setreuid(ncd.ncd_authuid, 0);
511 			kret = krb_get_cred(NFS_KERBSRV, inst, realm, &kcr);
512 			if (kret == RET_NOTKT) {
513 		            kret = get_ad_tkt(NFS_KERBSRV, inst, realm,
514 				DEFAULT_TKT_LIFE);
515 			    if (kret == KSUCCESS)
516 				kret = krb_get_cred(NFS_KERBSRV, inst, realm,
517 				    &kcr);
518 			}
519 			if (kret == KSUCCESS)
520 			    kret = krb_mk_req(&ktick.kt, NFS_KERBSRV, inst,
521 				realm, 0);
522 
523 			/*
524 			 * Fill in the AKN_FULLNAME authenticator and verifier.
525 			 * Along with the Kerberos ticket, we need to build
526 			 * the timestamp verifier and encrypt it in CBC mode.
527 			 */
528 			if (kret == KSUCCESS &&
529 			    ktick.kt.length <= (RPCAUTH_MAXSIZ-3*NFSX_UNSIGNED)
530 			    && gettimeofday(&ktv, (struct timezone *)0) == 0) {
531 			    ncd.ncd_authtype = RPCAUTH_KERB4;
532 			    ncd.ncd_authstr = (u_char *)&ktick;
533 			    ncd.ncd_authlen = nfsm_rndup(ktick.kt.length) +
534 				3 * NFSX_UNSIGNED;
535 			    ncd.ncd_verfstr = (u_char *)&kverf;
536 			    ncd.ncd_verflen = sizeof (kverf);
537 			    memmove(ncd.ncd_key, kcr.session,
538 				sizeof (kcr.session));
539 			    kin.t1 = htonl(ktv.tv_sec);
540 			    kin.t2 = htonl(ktv.tv_usec);
541 			    kin.w1 = htonl(NFS_KERBTTL);
542 			    kin.w2 = htonl(NFS_KERBTTL - 1);
543 			    bzero((caddr_t)kivec, sizeof (kivec));
544 
545 			    /*
546 			     * Encrypt kin in CBC mode using the session
547 			     * key in kcr.
548 			     */
549 			    XXX
550 
551 			    /*
552 			     * Finally, fill the timestamp verifier into the
553 			     * authenticator and verifier.
554 			     */
555 			    ktick.kind = htonl(RPCAKN_FULLNAME);
556 			    kverf.kind = htonl(RPCAKN_FULLNAME);
557 			    NFS_KERBW1(ktick.kt) = kout.w1;
558 			    ktick.kt.length = htonl(ktick.kt.length);
559 			    kverf.verf.t1 = kout.t1;
560 			    kverf.verf.t2 = kout.t2;
561 			    kverf.verf.w2 = kout.w2;
562 			    nfssvc_flag = NFSSVC_MNTD | NFSSVC_GOTAUTH;
563 			}
564 			setreuid(0, 0);
565 #endif /* NFSKERB */
566 		}
567 	}
568 	exit(0);
569 }
570 
571 static int
572 getnfsargs(char *spec, struct nfs_args *nfsargsp)
573 {
574 	struct hostent *hp;
575 	struct sockaddr_in saddr;
576 	enum tryret ret;
577 	int speclen, remoteerr;
578 	char *hostp, *delimp, *errstr;
579 #ifdef NFSKERB
580 	char *cp;
581 #endif
582 	size_t len;
583 	static char nam[MNAMELEN + 1];
584 
585 	if ((delimp = strrchr(spec, ':')) != NULL) {
586 		hostp = spec;
587 		spec = delimp + 1;
588 	} else if ((delimp = strrchr(spec, '@')) != NULL) {
589 		warnx("path@server syntax is deprecated, use server:path");
590 		hostp = delimp + 1;
591 	} else {
592 		warnx("no <host>:<dirpath> nfs-name");
593 		return (0);
594 	}
595 	*delimp = '\0';
596 
597 	/*
598 	 * If there has been a trailing slash at mounttime it seems
599 	 * that some mountd implementations fail to remove the mount
600 	 * entries from their mountlist while unmounting.
601 	 */
602 	for (speclen = strlen(spec);
603 		speclen > 1 && spec[speclen - 1] == '/';
604 		speclen--)
605 		spec[speclen - 1] = '\0';
606 	if (strlen(hostp) + strlen(spec) + 1 > MNAMELEN) {
607 		warnx("%s:%s: %s", hostp, spec, strerror(ENAMETOOLONG));
608 		return (0);
609 	}
610 	/* Make both '@' and ':' notations equal */
611 	if (*hostp != '\0') {
612 		len = strlen(hostp);
613 		memmove(nam, hostp, len);
614 		nam[len] = ':';
615 		memmove(nam + len + 1, spec, speclen);
616 		nam[len + speclen + 1] = '\0';
617 	}
618 
619 	/*
620 	 * Handle an internet host address and reverse resolve it if
621 	 * doing Kerberos.
622 	 */
623 	bzero(&saddr, sizeof saddr);
624 	saddr.sin_family = AF_INET;
625 	saddr.sin_len = sizeof saddr;
626 
627 	if (port_no != 0)
628 		saddr.sin_port = htons(port_no);
629 
630 	for (;;) {
631 		int haserror = 0;
632 
633 		/*
634 		 * Adjust DNS timeouts so we do not linger in the foreground
635 		 * if we can be backgrounded.
636 		 */
637 		switch(opflags & (BGRND | ISBGRND)) {
638 		case BGRND:
639 			_res.retry = 1;
640 			_res.retrans = 1;
641 			break;
642 		case BGRND|ISBGRND:
643 			_res.retry = 3;
644 			_res.retrans = 3;
645 			break;
646 		}
647 		if (isdigit(*hostp)) {
648 			saddr.sin_addr.s_addr = inet_addr(hostp);
649 			if (saddr.sin_addr.s_addr == INADDR_NONE) {
650 				warnx("bad net address %s", hostp);
651 				haserror = EAI_FAIL;
652 			}
653 		} else if ((hp = gethostbyname(hostp)) != NULL) {
654 			memmove(&saddr.sin_addr, hp->h_addr,
655 			    MIN(hp->h_length, (int)sizeof(saddr.sin_addr)));
656 		} else {
657 			warnx("can't get net id for host: %s", hostp);
658 			opflags |= DIDWARN;
659 			haserror = h_errno;
660 		}
661 #ifdef NFSKERB
662 		if (haserror == 0 && (nfsargsp->flags & NFSMNT_KERB)) {
663 			if ((hp = gethostbyaddr((char *)&saddr.sin_addr.s_addr,
664 			    sizeof (u_long), AF_INET)) == NULL) {
665 				warnx("can't reverse resolve net address");
666 				opflags |= DIDWARN;
667 				haserror = h_errno;
668 			} else {
669 				memmove(&saddr.sin_addr, hp->h_addr,
670 				    MIN(hp->h_length, sizeof(saddr.sin_addr)));
671 				strncpy(inst, hp->h_name, INST_SZ);
672 				inst[INST_SZ - 1] = '\0';
673 				if (cp = strchr(inst, '.'))
674 					*cp = '\0';
675 			}
676 		}
677 #endif /* NFSKERB */
678 		/*
679 		 * If no error occured we do not have to retry again.
680 		 * Otherwise try to backgruond us if possible.
681 		 */
682 		if (haserror == 0)
683 		    break;
684 
685 		switch(opflags & (BGRND | ISBGRND)) {
686 		case BGRND:
687 			if (haserror != EAI_AGAIN)
688 				return(0);
689 			/* recoverable error */
690 			warnx("Cannot immediately mount %s:%s, backgrounding",
691 			    hostp, spec);
692 			opflags |= DIDWARN;
693 			opflags |= ISBGRND;
694 			if (daemon(0, 0) != 0)
695 				err(1, "daemon");
696 			break;
697 		default:
698 			/*
699 			 * Already backgrounded or cannot be backgrounded.
700 			 */
701 			if (haserror != EAI_AGAIN)
702 				return(0);
703 			break;
704 		}
705 		sleep(20);
706 		endhostent();
707 	}
708 	if (opflags & DIDWARN) {
709 		opflags &= ~DIDWARN;
710 		warnx("successfully resolved %s after prior failures", hostp);
711 	}
712 
713 	ret = TRYRET_LOCALERR;
714 	for (;;) {
715 		remoteerr = 0;
716 		ret = nfs_tryproto(nfsargsp, &saddr, hostp, spec, &errstr);
717 		if (ret == TRYRET_SUCCESS)
718 			break;
719 		if (ret != TRYRET_LOCALERR)
720 			remoteerr = 1;
721 		if ((opflags & ISBGRND) == 0)
722 			fprintf(stderr, "%s\n", errstr);
723 
724 		/* Exit if all errors were local. */
725 		if (!remoteerr)
726 			exit(1);
727 
728 		/*
729 		 * If retrycnt == 0, we are to keep retrying forever.
730 		 * Otherwise decrement it, and exit if it hits zero.
731 		 */
732 		if (retrycnt != 0 && --retrycnt == 0)
733 			exit(1);
734 
735 		if ((opflags & (BGRND | ISBGRND)) == BGRND) {
736 			warnx("Cannot immediately mount %s:%s, backgrounding",
737 			    hostp, spec);
738 			opflags |= ISBGRND;
739 			opflags |= DIDWARN;
740 			if (daemon(0, 0) != 0)
741 				err(1, "daemon");
742 		}
743 		sleep(20);
744 	}
745 	if (opflags & DIDWARN) {
746 		opflags &= ~DIDWARN;
747 		warnx("successfully mounted %s after prior failures", spec);
748 	}
749 	nfsargsp->hostname = nam;
750 	/* Add mounted filesystem to PATH_MOUNTTAB */
751 	if (!add_mtab(hostp, spec))
752 		warnx("can't update %s for %s:%s", PATH_MOUNTTAB, hostp, spec);
753 	return (1);
754 }
755 
756 /*
757  * Try to set up the NFS arguments according to the address
758  * (and possibly port) specified by `sinp'.
759  *
760  * Returns TRYRET_SUCCESS if successful, or:
761  *   TRYRET_TIMEOUT		The server did not respond.
762  *   TRYRET_REMOTEERR		The server reported an error.
763  *   TRYRET_LOCALERR		Local failure.
764  *
765  * In all error cases, *errstr will be set to a statically-allocated string
766  * describing the error.
767  */
768 static enum tryret
769 nfs_tryproto(struct nfs_args *nfsargsp, struct sockaddr_in *sinp, char *hostp,
770     char *spec, char **errstr)
771 {
772 	static char errbuf[256];
773 	struct sockaddr_in sin, tmpsin;
774 	struct nfhret nfhret;
775 	struct timeval try;
776 	struct rpc_err rpcerr;
777 	CLIENT *clp;
778 	int doconnect, nfsvers, mntvers, so;
779 	enum clnt_stat status;
780 	enum mountmode trymntmode;
781 
782 	trymntmode = mountmode;
783 	errbuf[0] = '\0';
784 	*errstr = errbuf;
785 	sin = tmpsin = *sinp;
786 
787 tryagain:
788 	if (trymntmode == V2) {
789 		nfsvers = 2;
790 		mntvers = 1;
791 	} else {
792 		nfsvers = 3;
793 		mntvers = 3;
794 	}
795 
796 	/* Check that the server (nfsd) responds on the port we have chosen. */
797 	try.tv_sec = 10;
798 	try.tv_usec = 0;
799 	so = RPC_ANYSOCK;
800 	if (nfsargsp->sotype == SOCK_STREAM)
801 		clp = clnttcp_create(&sin, RPCPROG_NFS, nfsvers, &so, 0, 0);
802 	else
803 		clp = clntudp_create(&sin, RPCPROG_NFS, nfsvers, try, &so);
804 	if (clp == NULL) {
805 		snprintf(errbuf, sizeof errbuf, "%s:%s: %s",
806 		    hostp, spec, clnt_spcreateerror("nfsd: RPCPROG_NFS"));
807 		return (returncode(rpc_createerr.cf_stat,
808 		    &rpc_createerr.cf_error));
809 	}
810 	if (nfsargsp->sotype == SOCK_DGRAM &&
811 	    !(nfsargsp->flags & NFSMNT_NOCONN)) {
812 		/*
813 		 * Use connect(), to match what the kernel does. This
814 		 * catches cases where the server responds from the
815 		 * wrong source address.
816 		 */
817 		doconnect = 1;
818 		if (!clnt_control(clp, CLSET_CONNECT, (char *)&doconnect)) {
819 			clnt_destroy(clp);
820 			snprintf(errbuf, sizeof errbuf,
821 			    "%s:%s: CLSET_CONNECT failed", hostp, spec);
822 			return (TRYRET_LOCALERR);
823 		}
824 	}
825 
826 	try.tv_sec = 10;
827 	try.tv_usec = 0;
828 	status = clnt_call(clp, NFSPROC_NULL, xdr_void, NULL, xdr_void, NULL,
829 	    try);
830 	if (status != RPC_SUCCESS) {
831 		if (status == RPC_PROGVERSMISMATCH && trymntmode == ANY) {
832 			clnt_destroy(clp);
833 			trymntmode = V2;
834 			goto tryagain;
835 		}
836 		clnt_geterr(clp, &rpcerr);
837 		snprintf(errbuf, sizeof errbuf, "%s:%s: %s",
838 		    hostp, spec, clnt_sperror(clp, "NFSPROC_NULL"));
839 		clnt_destroy(clp);
840 		return (returncode(status, &rpcerr));
841 	}
842 	clnt_destroy(clp);
843 
844 	/* Send the RPCMNT_MOUNT RPC to get the root filehandle. */
845 	tmpsin.sin_port = 0;
846 	try.tv_sec = 10;
847 	try.tv_usec = 0;
848 	so = RPC_ANYSOCK;
849 	if (mnttcp_ok && nfsargsp->sotype == SOCK_STREAM)
850 		clp = clnttcp_create(&tmpsin, RPCPROG_MNT, mntvers, &so, 0, 0);
851 	else
852 		clp = clntudp_create(&tmpsin, RPCPROG_MNT, mntvers, try, &so);
853 	if (clp == NULL) {
854 		snprintf(errbuf, sizeof errbuf, "%s:%s: %s",
855 		    hostp, spec, clnt_spcreateerror("RPCMNT: clnt_create"));
856 		return (returncode(rpc_createerr.cf_stat,
857 		    &rpc_createerr.cf_error));
858 	}
859 	clp->cl_auth = authunix_create_default();
860 	if (nfsargsp->flags & NFSMNT_KERB)
861 		nfhret.auth = RPCAUTH_KERB4;
862 	else
863 		nfhret.auth = RPCAUTH_UNIX;
864 	nfhret.vers = mntvers;
865 	status = clnt_call(clp, RPCMNT_MOUNT, xdr_dir, spec, xdr_fh, &nfhret,
866 	    try);
867 	auth_destroy(clp->cl_auth);
868 	if (status != RPC_SUCCESS) {
869 		if (status == RPC_PROGVERSMISMATCH && trymntmode == ANY) {
870 			clnt_destroy(clp);
871 			trymntmode = V2;
872 			goto tryagain;
873 		}
874 		clnt_geterr(clp, &rpcerr);
875 		snprintf(errbuf, sizeof errbuf, "%s:%s: %s",
876 		    hostp, spec, clnt_sperror(clp, "RPCPROG_MNT"));
877 		clnt_destroy(clp);
878 		return (returncode(status, &rpcerr));
879 	}
880 	clnt_destroy(clp);
881 
882 	if (nfhret.stat != 0) {
883 		snprintf(errbuf, sizeof errbuf, "%s:%s: %s",
884 		    hostp, spec, strerror(nfhret.stat));
885 		return (TRYRET_REMOTEERR);
886 	}
887 
888 	/*
889 	 * Store the filehandle and server address in nfsargsp, making
890 	 * sure to copy any locally allocated structures.
891 	 */
892 	nfsargsp->addrlen = sin.sin_len;
893 	nfsargsp->addr = malloc(nfsargsp->addrlen);
894 	nfsargsp->fhsize = nfhret.fhsize;
895 	nfsargsp->fh = malloc(nfsargsp->fhsize);
896 	if (nfsargsp->addr == NULL || nfsargsp->fh == NULL)
897 		err(1, "malloc");
898 	bcopy(&sin, nfsargsp->addr, nfsargsp->addrlen);
899 	bcopy(nfhret.nfh, nfsargsp->fh, nfsargsp->fhsize);
900 
901 	if (nfsvers == 3)
902 		nfsargsp->flags |= NFSMNT_NFSV3;
903 	else
904 		nfsargsp->flags &= ~NFSMNT_NFSV3;
905 
906 	return (TRYRET_SUCCESS);
907 }
908 
909 /*
910  * Catagorise a RPC return status and error into an `enum tryret'
911  * return code.
912  */
913 static enum tryret
914 returncode(enum clnt_stat status, struct rpc_err *rpcerr)
915 {
916 	switch (status) {
917 	case RPC_TIMEDOUT:
918 		return (TRYRET_TIMEOUT);
919 	case RPC_PMAPFAILURE:
920 	case RPC_PROGNOTREGISTERED:
921 	case RPC_PROGVERSMISMATCH:
922 	/* XXX, these can be local or remote. */
923 	case RPC_CANTSEND:
924 	case RPC_CANTRECV:
925 		return (TRYRET_REMOTEERR);
926 	case RPC_SYSTEMERROR:
927 		switch (rpcerr->re_errno) {
928 		case ETIMEDOUT:
929 			return (TRYRET_TIMEOUT);
930 		case ENOMEM:
931 			break;
932 		default:
933 			return (TRYRET_REMOTEERR);
934 		}
935 		/* FALLTHROUGH */
936 	default:
937 		break;
938 	}
939 	return (TRYRET_LOCALERR);
940 }
941 
942 /*
943  * xdr routines for mount rpc's
944  */
945 static int
946 xdr_dir(XDR *xdrsp, char *dirp)
947 {
948 	return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN));
949 }
950 
951 static int
952 xdr_fh(XDR *xdrsp, struct nfhret *np)
953 {
954 	int i;
955 	long auth, authcnt, authfnd = 0;
956 
957 	if (!xdr_u_long(xdrsp, &np->stat))
958 		return (0);
959 	if (np->stat)
960 		return (1);
961 	switch (np->vers) {
962 	case 1:
963 		np->fhsize = NFSX_V2FH;
964 		return (xdr_opaque(xdrsp, (caddr_t)np->nfh, NFSX_V2FH));
965 	case 3:
966 		if (!xdr_long(xdrsp, &np->fhsize))
967 			return (0);
968 		if (np->fhsize <= 0 || np->fhsize > NFSX_V3FHMAX)
969 			return (0);
970 		if (!xdr_opaque(xdrsp, (caddr_t)np->nfh, np->fhsize))
971 			return (0);
972 		if (!xdr_long(xdrsp, &authcnt))
973 			return (0);
974 		for (i = 0; i < authcnt; i++) {
975 			if (!xdr_long(xdrsp, &auth))
976 				return (0);
977 			if (auth == np->auth)
978 				authfnd++;
979 		}
980 		/*
981 		 * Some servers, such as DEC's OSF/1 return a nil authenticator
982 		 * list to indicate RPCAUTH_UNIX.
983 		 */
984 		if (!authfnd && (authcnt > 0 || np->auth != RPCAUTH_UNIX))
985 			np->stat = EAUTH;
986 		return (1);
987 	};
988 	return (0);
989 }
990 
991 static void
992 usage(void)
993 {
994 	fprintf(stderr, "%s\n%s\n%s\n%s\n",
995 "usage: mount_nfs [-23KNPTUbcdilqs] [-D deadthresh] [-I readdirsize]",
996 "                 [-L leaseterm] [-R retrycnt] [-a maxreadahead]",
997 "                 [-g maxgroups] [-m realm] [-o options] [-r readsize]",
998 "                 [-t timeout] [-w writesize] [-x retrans] rhost:path node");
999 	exit(1);
1000 }
1001