xref: /dragonfly/sbin/mount_nfs/mount_nfs.c (revision bc3d4063)
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 1.14 2008/07/14 22:22:40 dillon 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 
55 #include <arpa/inet.h>
56 
57 #include <ctype.h>
58 #include <err.h>
59 #include <errno.h>
60 #include <netdb.h>
61 #include <stdio.h>
62 #include <stdlib.h>
63 #include <strings.h>
64 #include <sysexits.h>
65 #include <unistd.h>
66 #include <resolv.h>
67 
68 #include "mntopts.h"
69 #include "mounttab.h"
70 
71 #define	ALTF_BG		0x1
72 #define ALTF_NOCONN	0x2
73 #define ALTF_DUMBTIMR	0x4
74 #define ALTF_INTR	0x8
75 #define ALTF_KERB	0x10
76 #define ALTF_NFSV3	0x20
77 #define ALTF_RDIRPLUS	0x40
78 #define	ALTF_MNTUDP	0x80
79 #define ALTF_RESVPORT	0x100
80 #define ALTF_SEQPACKET	0x200
81 #define ALTF_UNUSED400	0x400
82 #define ALTF_SOFT	0x800
83 #define ALTF_TCP	0x1000
84 #define ALTF_PORT	0x2000
85 #define ALTF_NFSV2	0x4000
86 #define ALTF_ACREGMIN	0x8000
87 #define ALTF_ACREGMAX	0x10000
88 #define ALTF_ACDIRMIN	0x20000
89 #define ALTF_ACDIRMAX	0x40000
90 
91 struct mntopt mopts[] = {
92 	MOPT_STDOPTS,
93 	MOPT_FORCE,
94 	MOPT_UPDATE,
95 	MOPT_ASYNC,
96 	{ "bg", 0, ALTF_BG, 1 },
97 	{ "conn", 1, ALTF_NOCONN, 1 },
98 	{ "dumbtimer", 0, ALTF_DUMBTIMR, 1 },
99 	{ "intr", 0, ALTF_INTR, 1 },
100 #ifdef NFSKERB
101 	{ "kerb", 0, ALTF_KERB, 1 },
102 #endif
103 	{ "nfsv3", 0, ALTF_NFSV3, 1 },
104 	{ "rdirplus", 0, ALTF_RDIRPLUS, 1 },
105 	{ "mntudp", 0, ALTF_MNTUDP, 1 },
106 	{ "resvport", 0, ALTF_RESVPORT, 1 },
107 	{ "soft", 0, ALTF_SOFT, 1 },
108 	{ "tcp", 0, ALTF_TCP, 1 },
109 	{ "port=", 0, ALTF_PORT, 1 },
110 	{ "nfsv2", 0, ALTF_NFSV2, 1 },
111 	{ "acregmin=", 0, ALTF_ACREGMIN, 1 },
112 	{ "acregmax=", 0, ALTF_ACREGMAX, 1 },
113 	{ "acdirmin=", 0, ALTF_ACDIRMIN, 1 },
114 	{ "acdirmax=", 0, ALTF_ACDIRMAX, 1 },
115 	MOPT_NULL
116 };
117 
118 struct nfs_args nfsdefargs = {
119 	NFS_ARGSVERSION,
120 	(struct sockaddr *)0,
121 	sizeof (struct sockaddr_in),
122 	SOCK_DGRAM,
123 	0,
124 	(u_char *)0,
125 	0,
126 	NFSMNT_RESVPORT,
127 	NFS_WSIZE,
128 	NFS_RSIZE,
129 	NFS_READDIRSIZE,
130 	10,
131 	NFS_RETRANS,
132 	NFS_MAXGRPS,
133 	NFS_DEFRAHEAD,
134 	0,
135 	NFS_DEADTHRESH,
136 	(char *)0,
137 	/* args version 4 */
138 	NFS_MINATTRTIMO,
139 	NFS_MAXATTRTIMO,
140 	NFS_MINDIRATTRTIMO,
141 	NFS_MAXDIRATTRTIMO,
142 };
143 
144 struct nfhret {
145 	u_long		stat;
146 	long		vers;
147 	long		auth;
148 	long		fhsize;
149 	u_char		nfh[NFSX_V3FHMAX];
150 };
151 
152 #define	BGRND	0x0001
153 #define	ISBGRND	0x0002
154 #define DIDWARN 0x0004
155 
156 int retrycnt = -1;
157 int opflags = 0;
158 int nfsproto = IPPROTO_UDP;
159 int mnttcp_ok = 1;
160 u_short port_no = 0;
161 enum mountmode {
162 	ANY,
163 	V2,
164 	V3
165 } mountmode = ANY;
166 
167 #ifdef NFSKERB
168 char inst[INST_SZ];
169 char realm[REALM_SZ];
170 struct {
171 	u_long		kind;
172 	KTEXT_ST	kt;
173 } ktick;
174 struct nfsrpc_nickverf kverf;
175 struct nfsrpc_fullblock kin, kout;
176 NFSKERBKEY_T kivec;
177 CREDENTIALS kcr;
178 struct timeval ktv;
179 NFSKERBKEYSCHED_T kerb_keysched;
180 #endif
181 
182 /* Return codes for nfs_tryproto. */
183 enum tryret {
184 	TRYRET_SUCCESS,
185 	TRYRET_TIMEOUT,		/* No response received. */
186 	TRYRET_REMOTEERR,	/* Error received from remote server. */
187 	TRYRET_LOCALERR		/* Local failure. */
188 };
189 
190 void	set_rpc_maxgrouplist(int);
191 
192 static int	getnfsargs(char *, struct nfs_args *);
193 static void	usage(void) __dead2;
194 static int	xdr_dir(XDR *, char *);
195 static int	xdr_fh(XDR *, struct nfhret *);
196 static enum tryret
197 		nfs_tryproto(struct nfs_args *, struct sockaddr_in *,
198 			     char *, char *, char **);
199 static enum tryret
200 		returncode(enum clnt_stat, struct rpc_err *);
201 
202 /*
203  * Used to set mount flags with getmntopts.  Call with dir=TRUE to
204  * initialize altflags from the current mount flags.  Call with
205  * dir=FALSE to update mount flags with the new value of altflags after
206  * the call to getmntopts.
207  */
208 static void
209 set_flags(int* altflags, int* nfsflags, int dir)
210 {
211 #define F2(af, nf)					\
212 	if (dir) {					\
213 		if (*nfsflags & NFSMNT_##nf)		\
214 			*altflags |= ALTF_##af;		\
215 		else					\
216 			*altflags &= ~ALTF_##af;	\
217 	} else {					\
218 		if (*altflags & ALTF_##af)		\
219 			*nfsflags |= NFSMNT_##nf;	\
220 		else					\
221 			*nfsflags &= ~NFSMNT_##nf;	\
222 	}
223 #define F(f)	F2(f,f)
224 
225 	F(NOCONN);
226 	F(DUMBTIMR);
227 	F2(INTR, INT);
228 #ifdef NFSKERB
229 	F(KERB);
230 #endif
231 	F(RDIRPLUS);
232 	F(RESVPORT);
233 	F(SOFT);
234 	F(ACREGMIN);
235 	F(ACREGMAX);
236 	F(ACDIRMIN);
237 	F(ACDIRMAX);
238 
239 #undef F
240 #undef F2
241 }
242 
243 int
244 main(int argc, char **argv)
245 {
246 	int c;
247 	struct nfs_args *nfsargsp;
248 	struct nfs_args nfsargs;
249 	struct nfsd_cargs ncd;
250 	int mntflags, altflags, nfssvc_flag, num;
251 	char *name, *p, *spec;
252 	char mntpath[MAXPATHLEN];
253 	struct vfsconf vfc;
254 	int error = 0;
255 #ifdef NFSKERB
256 	uid_t last_ruid;
257 
258 	last_ruid = -1;
259 	strcpy(realm, KRB_REALM);
260 	if (sizeof (struct nfsrpc_nickverf) != RPCX_NICKVERF ||
261 	    sizeof (struct nfsrpc_fullblock) != RPCX_FULLBLOCK ||
262 	    ((char *)&ktick.kt) - ((char *)&ktick) != NFSX_UNSIGNED ||
263 	    ((char *)ktick.kt.dat) - ((char *)&ktick) != 2 * NFSX_UNSIGNED)
264 		fprintf(stderr, "Yikes! NFSKERB structs not packed!!\n");
265 #endif /* NFSKERB */
266 
267 	mntflags = 0;
268 	altflags = 0;
269 	nfsargs = nfsdefargs;
270 	nfsargsp = &nfsargs;
271 	while ((c = getopt(argc, argv,
272 	    "23a:bcdD:g:I:iKlm:No:PR:r:sTt:w:x:U")) != -1)
273 		switch (c) {
274 		case '2':
275 			mountmode = V2;
276 			break;
277 		case '3':
278 			mountmode = V3;
279 			break;
280 		case 'a':
281 			num = strtol(optarg, &p, 10);
282 			if (*p || num < 0)
283 				errx(1, "illegal -a value -- %s", optarg);
284 			nfsargsp->readahead = num;
285 			nfsargsp->flags |= NFSMNT_READAHEAD;
286 			break;
287 		case 'b':
288 			opflags |= BGRND;
289 			break;
290 		case 'c':
291 			nfsargsp->flags |= NFSMNT_NOCONN;
292 			break;
293 		case 'D':
294 			num = strtol(optarg, &p, 10);
295 			if (*p || num <= 0)
296 				errx(1, "illegal -D value -- %s", optarg);
297 			nfsargsp->deadthresh = num;
298 			nfsargsp->flags |= NFSMNT_DEADTHRESH;
299 			break;
300 		case 'd':
301 			nfsargsp->flags |= NFSMNT_DUMBTIMR;
302 			break;
303 		case 'g':
304 			num = strtol(optarg, &p, 10);
305 			if (*p || num <= 0)
306 				errx(1, "illegal -g value -- %s", optarg);
307 			set_rpc_maxgrouplist(num);
308 			nfsargsp->maxgrouplist = num;
309 			nfsargsp->flags |= NFSMNT_MAXGRPS;
310 			break;
311 		case 'I':
312 			num = strtol(optarg, &p, 10);
313 			if (*p || num <= 0)
314 				errx(1, "illegal -I value -- %s", optarg);
315 			nfsargsp->readdirsize = num;
316 			nfsargsp->flags |= NFSMNT_READDIRSIZE;
317 			break;
318 		case 'i':
319 			nfsargsp->flags |= NFSMNT_INT;
320 			break;
321 #ifdef NFSKERB
322 		case 'K':
323 			nfsargsp->flags |= NFSMNT_KERB;
324 			break;
325 #endif
326 		case 'l':
327 			nfsargsp->flags |= NFSMNT_RDIRPLUS;
328 			break;
329 #ifdef NFSKERB
330 		case 'm':
331 			strncpy(realm, optarg, REALM_SZ - 1);
332 			realm[REALM_SZ - 1] = '\0';
333 			break;
334 #endif
335 		case 'N':
336 			nfsargsp->flags &= ~NFSMNT_RESVPORT;
337 			break;
338 		case 'o':
339 			altflags = 0;
340 			set_flags(&altflags, &nfsargsp->flags, TRUE);
341 			if (mountmode == V2)
342 				altflags |= ALTF_NFSV2;
343 			else if (mountmode == V3)
344 				altflags |= ALTF_NFSV3;
345 			getmntopts(optarg, mopts, &mntflags, &altflags);
346 			set_flags(&altflags, &nfsargsp->flags, FALSE);
347 			/*
348 			 * Handle altflags which don't map directly to
349 			 * mount flags.
350 			 */
351 			if(altflags & ALTF_BG)
352 				opflags |= BGRND;
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 				port_no = atoi(strstr(optarg, "port=") + 5);
361 			mountmode = ANY;
362 			if(altflags & ALTF_NFSV2)
363 				mountmode = V2;
364 			if(altflags & ALTF_NFSV3)
365 				mountmode = V3;
366 			if(altflags & ALTF_ACREGMIN)
367 				nfsargsp->acregmin = atoi(strstr(optarg,
368 				    "acregmin=") + 9);
369 			if(altflags & ALTF_ACREGMAX)
370 				nfsargsp->acregmax = atoi(strstr(optarg,
371 				    "acregmax=") + 9);
372 			if(altflags & ALTF_ACDIRMIN)
373 				nfsargsp->acdirmin = atoi(strstr(optarg,
374 				    "acdirmin=") + 9);
375 			if(altflags & ALTF_ACDIRMAX)
376 				nfsargsp->acdirmax = atoi(strstr(optarg,
377 				    "acdirmax=") + 9);
378 			break;
379 		case 'P':
380 			/* obsolete for NFSMNT_RESVPORT, now default */
381 			break;
382 		case 'R':
383 			num = strtol(optarg, &p, 10);
384 			if (*p || num < 0)
385 				errx(1, "illegal -R value -- %s", optarg);
386 			retrycnt = num;
387 			break;
388 		case 'r':
389 			num = strtol(optarg, &p, 10);
390 			if (*p || num <= 0)
391 				errx(1, "illegal -r value -- %s", optarg);
392 			nfsargsp->rsize = num;
393 			nfsargsp->flags |= NFSMNT_RSIZE;
394 			break;
395 		case 's':
396 			nfsargsp->flags |= NFSMNT_SOFT;
397 			break;
398 		case 'T':
399 			nfsargsp->sotype = SOCK_STREAM;
400 			nfsproto = IPPROTO_TCP;
401 			break;
402 		case 't':
403 			num = strtol(optarg, &p, 10);
404 			if (*p || num <= 0)
405 				errx(1, "illegal -t value -- %s", optarg);
406 			nfsargsp->timeo = num;
407 			nfsargsp->flags |= NFSMNT_TIMEO;
408 			break;
409 		case 'w':
410 			num = strtol(optarg, &p, 10);
411 			if (*p || num <= 0)
412 				errx(1, "illegal -w value -- %s", optarg);
413 			nfsargsp->wsize = num;
414 			nfsargsp->flags |= NFSMNT_WSIZE;
415 			break;
416 		case 'x':
417 			num = strtol(optarg, &p, 10);
418 			if (*p || num <= 0)
419 				errx(1, "illegal -x value -- %s", optarg);
420 			nfsargsp->retrans = num;
421 			nfsargsp->flags |= NFSMNT_RETRANS;
422 			break;
423 		case 'U':
424 			mnttcp_ok = 0;
425 			break;
426 		default:
427 			usage();
428 			break;
429 		}
430 	argc -= optind;
431 	argv += optind;
432 
433 	if (argc != 2) {
434 		usage();
435 		/* NOTREACHED */
436 	}
437 
438 	spec = *argv++;
439 	name = *argv;
440 
441 	if (retrycnt == -1)
442 		/* The default is to keep retrying forever. */
443 		retrycnt = 0;
444 	if (!getnfsargs(spec, nfsargsp))
445 		exit(1);
446 
447 	/* resolve the mountpoint with realpath(3) */
448 	checkpath(name, mntpath);
449 
450 	error = getvfsbyname("nfs", &vfc);
451 	if (error && vfsisloadable("nfs")) {
452 		if(vfsload("nfs"))
453 			err(EX_OSERR, "vfsload(nfs)");
454 		endvfsent();	/* clear cache */
455 		error = getvfsbyname("nfs", &vfc);
456 	}
457 	if (error)
458 		errx(EX_OSERR, "nfs filesystem is not available");
459 
460 	if (mount(vfc.vfc_name, mntpath, mntflags, nfsargsp))
461 		err(1, "%s", mntpath);
462 	if (nfsargsp->flags & NFSMNT_KERB) {
463 		if ((opflags & ISBGRND) == 0) {
464 			if (daemon(0, 0) != 0)
465 				err(1, "daemon");
466 		}
467 		openlog("mount_nfs", LOG_PID, LOG_DAEMON);
468 		nfssvc_flag = NFSSVC_MNTD;
469 		ncd.ncd_dirp = mntpath;
470 		while (nfssvc(nfssvc_flag, (caddr_t)&ncd) < 0) {
471 			if (errno != ENEEDAUTH) {
472 				syslog(LOG_ERR, "nfssvc err %m");
473 				continue;
474 			}
475 			nfssvc_flag =
476 			    NFSSVC_MNTD | NFSSVC_GOTAUTH | NFSSVC_AUTHINFAIL;
477 #ifdef NFSKERB
478 			/*
479 			 * Set up as ncd_authuid for the kerberos call.
480 			 * Must set ruid to ncd_authuid and reset the
481 			 * ticket name iff ncd_authuid is not the same
482 			 * as last time, so that the right ticket file
483 			 * is found.
484 			 * Get the Kerberos credential structure so that
485 			 * we have the session key and get a ticket for
486 			 * this uid.
487 			 * For more info see the IETF Draft "Authentication
488 			 * in ONC RPC".
489 			 */
490 			if (ncd.ncd_authuid != last_ruid) {
491 				char buf[512];
492 				sprintf(buf, "%s%d", TKT_ROOT, ncd.ncd_authuid);
493 				krb_set_tkt_string(buf);
494 				last_ruid = ncd.ncd_authuid;
495 			}
496 			setreuid(ncd.ncd_authuid, 0);
497 			kret = krb_get_cred(NFS_KERBSRV, inst, realm, &kcr);
498 			if (kret == RET_NOTKT) {
499 		            kret = get_ad_tkt(NFS_KERBSRV, inst, realm,
500 				DEFAULT_TKT_LIFE);
501 			    if (kret == KSUCCESS)
502 				kret = krb_get_cred(NFS_KERBSRV, inst, realm,
503 				    &kcr);
504 			}
505 			if (kret == KSUCCESS)
506 			    kret = krb_mk_req(&ktick.kt, NFS_KERBSRV, inst,
507 				realm, 0);
508 
509 			/*
510 			 * Fill in the AKN_FULLNAME authenticator and verifier.
511 			 * Along with the Kerberos ticket, we need to build
512 			 * the timestamp verifier and encrypt it in CBC mode.
513 			 */
514 			if (kret == KSUCCESS &&
515 			    ktick.kt.length <= (RPCAUTH_MAXSIZ-3*NFSX_UNSIGNED)
516 			    && gettimeofday(&ktv, (struct timezone *)0) == 0) {
517 			    ncd.ncd_authtype = RPCAUTH_KERB4;
518 			    ncd.ncd_authstr = (u_char *)&ktick;
519 			    ncd.ncd_authlen = nfsm_rndup(ktick.kt.length) +
520 				3 * NFSX_UNSIGNED;
521 			    ncd.ncd_verfstr = (u_char *)&kverf;
522 			    ncd.ncd_verflen = sizeof (kverf);
523 			    memmove(ncd.ncd_key, kcr.session,
524 				sizeof (kcr.session));
525 			    kin.t1 = htonl(ktv.tv_sec);
526 			    kin.t2 = htonl(ktv.tv_usec);
527 			    kin.w1 = htonl(NFS_KERBTTL);
528 			    kin.w2 = htonl(NFS_KERBTTL - 1);
529 			    bzero((caddr_t)kivec, sizeof (kivec));
530 
531 			    /*
532 			     * Encrypt kin in CBC mode using the session
533 			     * key in kcr.
534 			     */
535 			    XXX
536 
537 			    /*
538 			     * Finally, fill the timestamp verifier into the
539 			     * authenticator and verifier.
540 			     */
541 			    ktick.kind = htonl(RPCAKN_FULLNAME);
542 			    kverf.kind = htonl(RPCAKN_FULLNAME);
543 			    NFS_KERBW1(ktick.kt) = kout.w1;
544 			    ktick.kt.length = htonl(ktick.kt.length);
545 			    kverf.verf.t1 = kout.t1;
546 			    kverf.verf.t2 = kout.t2;
547 			    kverf.verf.w2 = kout.w2;
548 			    nfssvc_flag = NFSSVC_MNTD | NFSSVC_GOTAUTH;
549 			}
550 			setreuid(0, 0);
551 #endif /* NFSKERB */
552 		}
553 	}
554 	exit(0);
555 }
556 
557 static int
558 getnfsargs(char *spec, struct nfs_args *nfsargsp)
559 {
560 	struct hostent *hp;
561 	struct sockaddr_in saddr;
562 	struct in_addr iaddr;
563 	enum tryret ret;
564 	int speclen, remoteerr;
565 	char *hostp, *delimp, *errstr;
566 #ifdef NFSKERB
567 	char *cp;
568 #endif
569 	size_t len;
570 	static char nam[MNAMELEN + 1];
571 
572 	if ((delimp = strrchr(spec, ':')) != NULL) {
573 		hostp = spec;
574 		spec = delimp + 1;
575 	} else if ((delimp = strrchr(spec, '@')) != NULL) {
576 		warnx("path@server syntax is deprecated, use server:path");
577 		hostp = delimp + 1;
578 	} else {
579 		warnx("no <host>:<dirpath> nfs-name");
580 		return (0);
581 	}
582 	*delimp = '\0';
583 
584 	/*
585 	 * If there has been a trailing slash at mounttime it seems
586 	 * that some mountd implementations fail to remove the mount
587 	 * entries from their mountlist while unmounting.
588 	 */
589 	for (speclen = strlen(spec);
590 		speclen > 1 && spec[speclen - 1] == '/';
591 		speclen--)
592 		spec[speclen - 1] = '\0';
593 	if (strlen(hostp) + strlen(spec) + 1 > MNAMELEN) {
594 		warnx("%s:%s: %s", hostp, spec, strerror(ENAMETOOLONG));
595 		return (0);
596 	}
597 	/* Make both '@' and ':' notations equal */
598 	if (*hostp != '\0') {
599 		len = strlen(hostp);
600 		memmove(nam, hostp, len);
601 		nam[len] = ':';
602 		memmove(nam + len + 1, spec, speclen);
603 		nam[len + speclen + 1] = '\0';
604 	}
605 
606 	/*
607 	 * Handle an internet host address and reverse resolve it if
608 	 * doing Kerberos.
609 	 */
610 	bzero(&saddr, sizeof saddr);
611 	saddr.sin_family = AF_INET;
612 	saddr.sin_len = sizeof saddr;
613 
614 	if (port_no != 0)
615 		saddr.sin_port = htons(port_no);
616 
617 	for (;;) {
618 		int haserror = 0;
619 
620 		/*
621 		 * Adjust DNS timeouts so we do not linger in the foreground
622 		 * if we can be backgrounded.
623 		 */
624 		switch(opflags & (BGRND | ISBGRND)) {
625 		case BGRND:
626 			_res.retry = 1;
627 			_res.retrans = 1;
628 			break;
629 		case BGRND|ISBGRND:
630 			_res.retry = 3;
631 			_res.retrans = 3;
632 			break;
633 		}
634 		if (inet_pton(AF_INET, hostp, &iaddr) == 1) {
635 			saddr.sin_addr = iaddr;
636 		} else if ((hp = gethostbyname(hostp)) != NULL) {
637 			memmove(&saddr.sin_addr, hp->h_addr,
638 			    MIN(hp->h_length, (int)sizeof(saddr.sin_addr)));
639 		} else {
640 			warnx("can't get net id for host: %s", hostp);
641 			opflags |= DIDWARN;
642 			haserror = h_errno;
643 		}
644 #ifdef NFSKERB
645 		if (haserror == 0 && (nfsargsp->flags & NFSMNT_KERB)) {
646 			if ((hp = gethostbyaddr((char *)&saddr.sin_addr.s_addr,
647 			    sizeof (u_long), AF_INET)) == NULL) {
648 				warnx("can't reverse resolve net address");
649 				opflags |= DIDWARN;
650 				haserror = h_errno;
651 			} else {
652 				memmove(&saddr.sin_addr, hp->h_addr,
653 				    MIN(hp->h_length, sizeof(saddr.sin_addr)));
654 				strncpy(inst, hp->h_name, INST_SZ);
655 				inst[INST_SZ - 1] = '\0';
656 				if (cp = strchr(inst, '.'))
657 					*cp = '\0';
658 			}
659 		}
660 #endif /* NFSKERB */
661 		/*
662 		 * If no error occured we do not have to retry again.
663 		 * Otherwise try to backgruond us if possible.
664 		 */
665 		if (haserror == 0)
666 		    break;
667 
668 		switch(opflags & (BGRND | ISBGRND)) {
669 		case BGRND:
670 			if (haserror != EAI_AGAIN)
671 				return(0);
672 			/* recoverable error */
673 			warnx("Cannot immediately mount %s:%s, backgrounding",
674 			    hostp, spec);
675 			opflags |= DIDWARN;
676 			opflags |= ISBGRND;
677 			if (daemon(0, 0) != 0)
678 				err(1, "daemon");
679 			break;
680 		default:
681 			/*
682 			 * Already backgrounded or cannot be backgrounded.
683 			 */
684 			if (haserror != EAI_AGAIN)
685 				return(0);
686 			break;
687 		}
688 		sleep(20);
689 		endhostent();
690 	}
691 	if (opflags & DIDWARN) {
692 		opflags &= ~DIDWARN;
693 		warnx("successfully resolved %s after prior failures", hostp);
694 	}
695 
696 	ret = TRYRET_LOCALERR;
697 	for (;;) {
698 		remoteerr = 0;
699 		ret = nfs_tryproto(nfsargsp, &saddr, hostp, spec, &errstr);
700 		if (ret == TRYRET_SUCCESS)
701 			break;
702 		if (ret != TRYRET_LOCALERR)
703 			remoteerr = 1;
704 		if ((opflags & ISBGRND) == 0)
705 			fprintf(stderr, "%s\n", errstr);
706 
707 		/* Exit if all errors were local. */
708 		if (!remoteerr)
709 			exit(1);
710 
711 		/*
712 		 * If retrycnt == 0, we are to keep retrying forever.
713 		 * Otherwise decrement it, and exit if it hits zero.
714 		 */
715 		if (retrycnt != 0 && --retrycnt == 0)
716 			exit(1);
717 
718 		if ((opflags & (BGRND | ISBGRND)) == BGRND) {
719 			warnx("Cannot immediately mount %s:%s, backgrounding",
720 			    hostp, spec);
721 			opflags |= ISBGRND;
722 			opflags |= DIDWARN;
723 			if (daemon(0, 0) != 0)
724 				err(1, "daemon");
725 		}
726 		sleep(20);
727 	}
728 	if (opflags & DIDWARN) {
729 		opflags &= ~DIDWARN;
730 		warnx("successfully mounted %s after prior failures", spec);
731 	}
732 	nfsargsp->hostname = nam;
733 	/* Add mounted filesystem to PATH_MOUNTTAB */
734 	if (!add_mtab(hostp, spec))
735 		warnx("can't update %s for %s:%s", PATH_MOUNTTAB, hostp, spec);
736 	return (1);
737 }
738 
739 /*
740  * Try to set up the NFS arguments according to the address
741  * (and possibly port) specified by `sinp'.
742  *
743  * Returns TRYRET_SUCCESS if successful, or:
744  *   TRYRET_TIMEOUT		The server did not respond.
745  *   TRYRET_REMOTEERR		The server reported an error.
746  *   TRYRET_LOCALERR		Local failure.
747  *
748  * In all error cases, *errstr will be set to a statically-allocated string
749  * describing the error.
750  */
751 static enum tryret
752 nfs_tryproto(struct nfs_args *nfsargsp, struct sockaddr_in *sinp, char *hostp,
753     char *spec, char **errstr)
754 {
755 	static char errbuf[256];
756 	struct sockaddr_in sin, tmpsin;
757 	struct nfhret nfhret;
758 	struct timeval try;
759 	struct rpc_err rpcerr;
760 	CLIENT *clp;
761 	int doconnect, nfsvers, mntvers, so;
762 	enum clnt_stat status;
763 	enum mountmode trymntmode;
764 
765 	trymntmode = mountmode;
766 	errbuf[0] = '\0';
767 	*errstr = errbuf;
768 	sin = tmpsin = *sinp;
769 
770 tryagain:
771 	if (trymntmode == V2) {
772 		nfsvers = 2;
773 		mntvers = 1;
774 	} else {
775 		nfsvers = 3;
776 		mntvers = 3;
777 	}
778 
779 	/* Check that the server (nfsd) responds on the port we have chosen. */
780 	try.tv_sec = 10;
781 	try.tv_usec = 0;
782 	so = RPC_ANYSOCK;
783 	if (nfsargsp->sotype == SOCK_STREAM)
784 		clp = clnttcp_create(&sin, RPCPROG_NFS, nfsvers, &so, 0, 0);
785 	else
786 		clp = clntudp_create(&sin, RPCPROG_NFS, nfsvers, try, &so);
787 	if (clp == NULL) {
788 		snprintf(errbuf, sizeof errbuf, "%s:%s: %s",
789 		    hostp, spec, clnt_spcreateerror("nfsd: RPCPROG_NFS"));
790 		return (returncode(rpc_createerr.cf_stat,
791 		    &rpc_createerr.cf_error));
792 	}
793 	if (nfsargsp->sotype == SOCK_DGRAM &&
794 	    !(nfsargsp->flags & NFSMNT_NOCONN)) {
795 		/*
796 		 * Use connect(), to match what the kernel does. This
797 		 * catches cases where the server responds from the
798 		 * wrong source address.
799 		 */
800 		doconnect = 1;
801 		if (!clnt_control(clp, CLSET_CONNECT, (char *)&doconnect)) {
802 			clnt_destroy(clp);
803 			snprintf(errbuf, sizeof errbuf,
804 			    "%s:%s: CLSET_CONNECT failed", hostp, spec);
805 			return (TRYRET_LOCALERR);
806 		}
807 	}
808 
809 	try.tv_sec = 10;
810 	try.tv_usec = 0;
811 	status = clnt_call(clp, NFSPROC_NULL, xdr_void, NULL, xdr_void, NULL,
812 	    try);
813 	if (status != RPC_SUCCESS) {
814 		if (status == RPC_PROGVERSMISMATCH && trymntmode == ANY) {
815 			clnt_destroy(clp);
816 			trymntmode = V2;
817 			goto tryagain;
818 		}
819 		clnt_geterr(clp, &rpcerr);
820 		snprintf(errbuf, sizeof errbuf, "%s:%s: %s",
821 		    hostp, spec, clnt_sperror(clp, "NFSPROC_NULL"));
822 		clnt_destroy(clp);
823 		return (returncode(status, &rpcerr));
824 	}
825 	clnt_destroy(clp);
826 
827 	/* Send the RPCMNT_MOUNT RPC to get the root filehandle. */
828 	tmpsin.sin_port = 0;
829 	try.tv_sec = 10;
830 	try.tv_usec = 0;
831 	so = RPC_ANYSOCK;
832 	if (mnttcp_ok && nfsargsp->sotype == SOCK_STREAM)
833 		clp = clnttcp_create(&tmpsin, RPCPROG_MNT, mntvers, &so, 0, 0);
834 	else
835 		clp = clntudp_create(&tmpsin, RPCPROG_MNT, mntvers, try, &so);
836 	if (clp == NULL) {
837 		snprintf(errbuf, sizeof errbuf, "%s:%s: %s",
838 		    hostp, spec, clnt_spcreateerror("RPCMNT: clnt_create"));
839 		return (returncode(rpc_createerr.cf_stat,
840 		    &rpc_createerr.cf_error));
841 	}
842 	clp->cl_auth = authunix_create_default();
843 	if (nfsargsp->flags & NFSMNT_KERB)
844 		nfhret.auth = RPCAUTH_KERB4;
845 	else
846 		nfhret.auth = RPCAUTH_UNIX;
847 	nfhret.vers = mntvers;
848 	status = clnt_call(clp, RPCMNT_MOUNT, xdr_dir, spec, xdr_fh, &nfhret,
849 	    try);
850 	auth_destroy(clp->cl_auth);
851 	if (status != RPC_SUCCESS) {
852 		if (status == RPC_PROGVERSMISMATCH && trymntmode == ANY) {
853 			clnt_destroy(clp);
854 			trymntmode = V2;
855 			goto tryagain;
856 		}
857 		clnt_geterr(clp, &rpcerr);
858 		snprintf(errbuf, sizeof errbuf, "%s:%s: %s",
859 		    hostp, spec, clnt_sperror(clp, "RPCPROG_MNT"));
860 		clnt_destroy(clp);
861 		return (returncode(status, &rpcerr));
862 	}
863 	clnt_destroy(clp);
864 
865 	if (nfhret.stat != 0) {
866 		snprintf(errbuf, sizeof errbuf, "%s:%s: %s",
867 		    hostp, spec, strerror(nfhret.stat));
868 		return (TRYRET_REMOTEERR);
869 	}
870 
871 	/*
872 	 * Store the filehandle and server address in nfsargsp, making
873 	 * sure to copy any locally allocated structures.
874 	 */
875 	nfsargsp->addrlen = sin.sin_len;
876 	nfsargsp->addr = malloc(nfsargsp->addrlen);
877 	nfsargsp->fhsize = nfhret.fhsize;
878 	nfsargsp->fh = malloc(nfsargsp->fhsize);
879 	if (nfsargsp->addr == NULL || nfsargsp->fh == NULL)
880 		err(1, "malloc");
881 	bcopy(&sin, nfsargsp->addr, nfsargsp->addrlen);
882 	bcopy(nfhret.nfh, nfsargsp->fh, nfsargsp->fhsize);
883 
884 	if (nfsvers == 3)
885 		nfsargsp->flags |= NFSMNT_NFSV3;
886 	else
887 		nfsargsp->flags &= ~NFSMNT_NFSV3;
888 
889 	return (TRYRET_SUCCESS);
890 }
891 
892 /*
893  * Catagorise a RPC return status and error into an `enum tryret'
894  * return code.
895  */
896 static enum tryret
897 returncode(enum clnt_stat status, struct rpc_err *rpcerr)
898 {
899 	switch (status) {
900 	case RPC_TIMEDOUT:
901 		return (TRYRET_TIMEOUT);
902 	case RPC_PMAPFAILURE:
903 	case RPC_PROGNOTREGISTERED:
904 	case RPC_PROGVERSMISMATCH:
905 	/* XXX, these can be local or remote. */
906 	case RPC_CANTSEND:
907 	case RPC_CANTRECV:
908 		return (TRYRET_REMOTEERR);
909 	case RPC_SYSTEMERROR:
910 		switch (rpcerr->re_errno) {
911 		case ETIMEDOUT:
912 			return (TRYRET_TIMEOUT);
913 		case ENOMEM:
914 			break;
915 		default:
916 			return (TRYRET_REMOTEERR);
917 		}
918 		/* FALLTHROUGH */
919 	default:
920 		break;
921 	}
922 	return (TRYRET_LOCALERR);
923 }
924 
925 /*
926  * xdr routines for mount rpc's
927  */
928 static int
929 xdr_dir(XDR *xdrsp, char *dirp)
930 {
931 	return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN));
932 }
933 
934 static int
935 xdr_fh(XDR *xdrsp, struct nfhret *np)
936 {
937 	int i;
938 	long auth, authcnt, authfnd = 0;
939 
940 	if (!xdr_u_long(xdrsp, &np->stat))
941 		return (0);
942 	if (np->stat)
943 		return (1);
944 	switch (np->vers) {
945 	case 1:
946 		np->fhsize = NFSX_V2FH;
947 		return (xdr_opaque(xdrsp, (caddr_t)np->nfh, NFSX_V2FH));
948 	case 3:
949 		if (!xdr_long(xdrsp, &np->fhsize))
950 			return (0);
951 		if (np->fhsize <= 0 || np->fhsize > NFSX_V3FHMAX)
952 			return (0);
953 		if (!xdr_opaque(xdrsp, (caddr_t)np->nfh, np->fhsize))
954 			return (0);
955 		if (!xdr_long(xdrsp, &authcnt))
956 			return (0);
957 		for (i = 0; i < authcnt; i++) {
958 			if (!xdr_long(xdrsp, &auth))
959 				return (0);
960 			if (auth == np->auth)
961 				authfnd++;
962 		}
963 		/*
964 		 * Some servers, such as DEC's OSF/1 return a nil authenticator
965 		 * list to indicate RPCAUTH_UNIX.
966 		 */
967 		if (!authfnd && (authcnt > 0 || np->auth != RPCAUTH_UNIX))
968 			np->stat = EAUTH;
969 		return (1);
970 	};
971 	return (0);
972 }
973 
974 static void
975 usage(void)
976 {
977 	fprintf(stderr, "%s\n%s\n%s\n%s\n",
978 "usage: mount_nfs [-23KNPTUbcdils] [-D deadthresh] [-I readdirsize]",
979 "                 [-R retrycnt] [-a maxreadahead]",
980 "                 [-g maxgroups] [-m realm] [-o options] [-r readsize]",
981 "                 [-t timeout] [-w writesize] [-x retrans] rhost:path node");
982 	exit(1);
983 }
984