xref: /freebsd/sbin/mount_nfs/mount_nfs.c (revision dad64f0e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1992, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Rick Macklem at The University of Guelph.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #if 0
36 #ifndef lint
37 static const char copyright[] =
38 "@(#) Copyright (c) 1992, 1993, 1994\n\
39 	The Regents of the University of California.  All rights reserved.\n";
40 #endif /* not lint */
41 
42 #ifndef lint
43 static char sccsid[] = "@(#)mount_nfs.c	8.11 (Berkeley) 5/4/95";
44 #endif /* not lint */
45 #endif
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
48 
49 #include <sys/param.h>
50 #include <sys/linker.h>
51 #include <sys/module.h>
52 #include <sys/mount.h>
53 #include <sys/socket.h>
54 #include <sys/stat.h>
55 #include <sys/syslog.h>
56 #include <sys/uio.h>
57 
58 #include <rpc/rpc.h>
59 #include <rpc/pmap_clnt.h>
60 #include <rpc/pmap_prot.h>
61 #include <rpcsvc/nfs_prot.h>
62 #include <rpcsvc/mount.h>
63 
64 #include <fs/nfs/nfsproto.h>
65 #include <fs/nfs/nfsv4_errstr.h>
66 
67 #include <arpa/inet.h>
68 #include <net/route.h>
69 #include <net/if.h>
70 
71 #include <ctype.h>
72 #include <err.h>
73 #include <errno.h>
74 #include <fcntl.h>
75 #include <netdb.h>
76 #include <stdbool.h>
77 #include <stdio.h>
78 #include <stdlib.h>
79 #include <string.h>
80 #include <strings.h>
81 #include <sysexits.h>
82 #include <unistd.h>
83 
84 #include "mntopts.h"
85 #include "mounttab.h"
86 
87 /* Table for af,sotype -> netid conversions. */
88 static struct nc_protos {
89 	const char *netid;
90 	int af;
91 	int sotype;
92 } nc_protos[] = {
93 	{"udp",		AF_INET,	SOCK_DGRAM},
94 	{"tcp",		AF_INET,	SOCK_STREAM},
95 	{"udp6",	AF_INET6,	SOCK_DGRAM},
96 	{"tcp6",	AF_INET6,	SOCK_STREAM},
97 	{NULL,		0,		0}
98 };
99 
100 struct nfhret {
101 	u_long		stat;
102 	long		vers;
103 	long		auth;
104 	long		fhsize;
105 	u_char		nfh[NFS3_FHSIZE];
106 };
107 #define	BGRND		0x01
108 #define	ISBGRND		0x02
109 #define	OF_NOINET4	0x04
110 #define	OF_NOINET6	0x08
111 #define	BGRNDNOW	0x10
112 static int retrycnt = -1;
113 static int opflags = 0;
114 static int nfsproto = IPPROTO_TCP;
115 static int mnttcp_ok = 1;
116 static int noconn = 0;
117 /* The 'portspec' is the server nfs port; NULL means look up via rpcbind. */
118 static const char *portspec = NULL;
119 static struct sockaddr *addr;
120 static int addrlen = 0;
121 static u_char *fh = NULL;
122 static int fhsize = 0;
123 static int secflavor = -1;
124 static int got_principal = 0;
125 
126 static enum mountmode {
127 	ANY,
128 	V2,
129 	V3,
130 	V4
131 } mountmode = ANY;
132 
133 /* Return codes for nfs_tryproto. */
134 enum tryret {
135 	TRYRET_SUCCESS,
136 	TRYRET_TIMEOUT,		/* No response received. */
137 	TRYRET_REMOTEERR,	/* Error received from remote server. */
138 	TRYRET_LOCALERR		/* Local failure. */
139 };
140 
141 static int	sec_name_to_num(const char *sec);
142 static const char	*sec_num_to_name(int num);
143 static int	getnfsargs(char **, char **, struct iovec **iov, int *iovlen);
144 /* void	set_rpc_maxgrouplist(int); */
145 static struct netconfig *getnetconf_cached(const char *netid);
146 static const char	*netidbytype(int af, int sotype);
147 static void	usage(void) __dead2;
148 static int	xdr_dir(XDR *, char *);
149 static int	xdr_fh(XDR *, struct nfhret *);
150 static enum tryret nfs_tryproto(struct addrinfo *ai, char *hostp, char *spec,
151     char **errstr, struct iovec **iov, int *iovlen);
152 static enum tryret returncode(enum clnt_stat stat, struct rpc_err *rpcerr);
153 
154 int
155 main(int argc, char *argv[])
156 {
157 	int c;
158 	struct iovec *iov;
159 	int num, iovlen;
160 	char *host, *mntname, *p, *spec, *tmp;
161 	char mntpath[MAXPATHLEN], errmsg[255];
162 	char hostname[MAXHOSTNAMELEN + 1], gssn[MAXHOSTNAMELEN + 50];
163 	const char *gssname, *nmount_errstr;
164 	bool softintr;
165 
166 	softintr = false;
167 	iov = NULL;
168 	iovlen = 0;
169 	memset(errmsg, 0, sizeof(errmsg));
170 	gssname = NULL;
171 
172 	while ((c = getopt(argc, argv,
173 	    "23a:bcdD:g:I:iLlNo:PR:r:sTt:w:x:U")) != -1)
174 		switch (c) {
175 		case '2':
176 			mountmode = V2;
177 			break;
178 		case '3':
179 			mountmode = V3;
180 			break;
181 		case 'a':
182 			printf("-a deprecated, use -o readahead=<value>\n");
183 			build_iovec(&iov, &iovlen, "readahead", optarg, (size_t)-1);
184 			break;
185 		case 'b':
186 			opflags |= BGRND;
187 			break;
188 		case 'c':
189 			printf("-c deprecated, use -o noconn\n");
190 			build_iovec(&iov, &iovlen, "noconn", NULL, 0);
191 			noconn = 1;
192 			break;
193 		case 'D':
194 			printf("-D deprecated, use -o deadthresh=<value>\n");
195 			build_iovec(&iov, &iovlen, "deadthresh", optarg, (size_t)-1);
196 			break;
197 		case 'd':
198 			printf("-d deprecated, use -o dumbtimer");
199 			build_iovec(&iov, &iovlen, "dumbtimer", NULL, 0);
200 			break;
201 		case 'g':
202 			printf("-g deprecated, use -o maxgroups");
203 			num = strtol(optarg, &p, 10);
204 			if (*p || num <= 0)
205 				errx(1, "illegal -g value -- %s", optarg);
206 			//set_rpc_maxgrouplist(num);
207 			build_iovec(&iov, &iovlen, "maxgroups", optarg, (size_t)-1);
208 			break;
209 		case 'I':
210 			printf("-I deprecated, use -o readdirsize=<value>\n");
211 			build_iovec(&iov, &iovlen, "readdirsize", optarg, (size_t)-1);
212 			break;
213 		case 'i':
214 			printf("-i deprecated, use -o intr\n");
215 			build_iovec(&iov, &iovlen, "intr", NULL, 0);
216 			softintr = true;
217 			break;
218 		case 'L':
219 			printf("-L deprecated, use -o nolockd\n");
220 			build_iovec(&iov, &iovlen, "nolockd", NULL, 0);
221 			break;
222 		case 'l':
223 			printf("-l deprecated, -o rdirplus\n");
224 			build_iovec(&iov, &iovlen, "rdirplus", NULL, 0);
225 			break;
226 		case 'N':
227 			printf("-N deprecated, do not specify -o resvport\n");
228 			break;
229 		case 'o': {
230 			int pass_flag_to_nmount;
231 			char *opt = optarg;
232 			while (opt) {
233 				char *pval = NULL;
234 				char *pnextopt = NULL;
235 				const char *val = "";
236 				pass_flag_to_nmount = 1;
237 				pnextopt = strchr(opt, ',');
238 				if (pnextopt != NULL) {
239 					*pnextopt = '\0';
240 					pnextopt++;
241 				}
242 				pval = strchr(opt, '=');
243 				if (pval != NULL) {
244 					*pval = '\0';
245 					val = pval + 1;
246 				}
247 				if (strcmp(opt, "bg") == 0) {
248 					opflags |= BGRND;
249 					pass_flag_to_nmount=0;
250 				} else if (strcmp(opt, "bgnow") == 0) {
251 					opflags |= BGRNDNOW;
252 					pass_flag_to_nmount=0;
253 				} else if (strcmp(opt, "fg") == 0) {
254 					/* same as not specifying -o bg */
255 					pass_flag_to_nmount=0;
256 				} else if (strcmp(opt, "gssname") == 0) {
257 					pass_flag_to_nmount = 0;
258 					gssname = val;
259 				} else if (strcmp(opt, "mntudp") == 0) {
260 					mnttcp_ok = 0;
261 					nfsproto = IPPROTO_UDP;
262 				} else if (strcmp(opt, "udp") == 0) {
263 					nfsproto = IPPROTO_UDP;
264 				} else if (strcmp(opt, "tcp") == 0) {
265 					nfsproto = IPPROTO_TCP;
266 				} else if (strcmp(opt, "noinet4") == 0) {
267 					pass_flag_to_nmount=0;
268 					opflags |= OF_NOINET4;
269 				} else if (strcmp(opt, "noinet6") == 0) {
270 					pass_flag_to_nmount=0;
271 					opflags |= OF_NOINET6;
272 				} else if (strcmp(opt, "noconn") == 0) {
273 					noconn = 1;
274 				} else if (strcmp(opt, "nfsv2") == 0) {
275 					pass_flag_to_nmount=0;
276 					mountmode = V2;
277 				} else if (strcmp(opt, "nfsv3") == 0) {
278 					mountmode = V3;
279 				} else if (strcmp(opt, "nfsv4") == 0) {
280 					pass_flag_to_nmount=0;
281 					mountmode = V4;
282 					nfsproto = IPPROTO_TCP;
283 					if (portspec == NULL)
284 						portspec = "2049";
285 				} else if (strcmp(opt, "port") == 0) {
286 					pass_flag_to_nmount=0;
287 					asprintf(&tmp, "%d", atoi(val));
288 					if (tmp == NULL)
289 						err(1, "asprintf");
290 					portspec = tmp;
291 				} else if (strcmp(opt, "principal") == 0) {
292 					got_principal = 1;
293 				} else if (strcmp(opt, "proto") == 0) {
294 					pass_flag_to_nmount=0;
295 					if (strcmp(val, "tcp") == 0) {
296 						nfsproto = IPPROTO_TCP;
297 						opflags |= OF_NOINET6;
298 						build_iovec(&iov, &iovlen,
299 						    "tcp", NULL, 0);
300 					} else if (strcmp(val, "udp") == 0) {
301 						mnttcp_ok = 0;
302 						nfsproto = IPPROTO_UDP;
303 						opflags |= OF_NOINET6;
304 						build_iovec(&iov, &iovlen,
305 						    "udp", NULL, 0);
306 					} else if (strcmp(val, "tcp6") == 0) {
307 						nfsproto = IPPROTO_TCP;
308 						opflags |= OF_NOINET4;
309 						build_iovec(&iov, &iovlen,
310 						    "tcp", NULL, 0);
311 					} else if (strcmp(val, "udp6") == 0) {
312 						mnttcp_ok = 0;
313 						nfsproto = IPPROTO_UDP;
314 						opflags |= OF_NOINET4;
315 						build_iovec(&iov, &iovlen,
316 						    "udp", NULL, 0);
317 					} else {
318 						errx(1,
319 						    "illegal proto value -- %s",
320 						    val);
321 					}
322 				} else if (strcmp(opt, "sec") == 0) {
323 					/*
324 					 * Don't add this option to
325 					 * the iovec yet - we will
326 					 * negotiate which sec flavor
327 					 * to use with the remote
328 					 * mountd.
329 					 */
330 					pass_flag_to_nmount=0;
331 					secflavor = sec_name_to_num(val);
332 					if (secflavor < 0) {
333 						errx(1,
334 						    "illegal sec value -- %s",
335 						    val);
336 					}
337 				} else if (strcmp(opt, "retrycnt") == 0) {
338 					pass_flag_to_nmount=0;
339 					num = strtol(val, &p, 10);
340 					if (*p || num < 0)
341 						errx(1, "illegal retrycnt value -- %s", val);
342 					retrycnt = num;
343 				} else if (strcmp(opt, "maxgroups") == 0) {
344 					num = strtol(val, &p, 10);
345 					if (*p || num <= 0)
346 						errx(1, "illegal maxgroups value -- %s", val);
347 					//set_rpc_maxgrouplist(num);
348 				} else if (strcmp(opt, "vers") == 0) {
349 					num = strtol(val, &p, 10);
350 					if (*p || num <= 0)
351 						errx(1, "illegal vers value -- "
352 						    "%s", val);
353 					switch (num) {
354 					case 2:
355 						mountmode = V2;
356 						break;
357 					case 3:
358 						mountmode = V3;
359 						build_iovec(&iov, &iovlen,
360 						    "nfsv3", NULL, 0);
361 						break;
362 					case 4:
363 						mountmode = V4;
364 						nfsproto = IPPROTO_TCP;
365 						if (portspec == NULL)
366 							portspec = "2049";
367 						break;
368 					default:
369 						errx(1, "illegal nfs version "
370 						    "value -- %s", val);
371 					}
372 					pass_flag_to_nmount=0;
373 				} else if (strcmp(opt, "soft") == 0) {
374 					softintr = true;
375 				} else if (strcmp(opt, "intr") == 0) {
376 					softintr = true;
377 				}
378 				if (pass_flag_to_nmount) {
379 					build_iovec(&iov, &iovlen, opt,
380 					    __DECONST(void *, val),
381 					    strlen(val) + 1);
382 				}
383 				opt = pnextopt;
384 			}
385 			}
386 			break;
387 		case 'P':
388 			/* obsolete for -o noresvport now default */
389 			printf("-P deprecated, use -o noresvport\n");
390 			build_iovec(&iov, &iovlen, "noresvport", NULL, 0);
391 			break;
392 		case 'R':
393 			printf("-R deprecated, use -o retrycnt=<retrycnt>\n");
394 			num = strtol(optarg, &p, 10);
395 			if (*p || num < 0)
396 				errx(1, "illegal -R value -- %s", optarg);
397 			retrycnt = num;
398 			break;
399 		case 'r':
400 			printf("-r deprecated, use -o rsize=<rsize>\n");
401 			build_iovec(&iov, &iovlen, "rsize", optarg, (size_t)-1);
402 			break;
403 		case 's':
404 			printf("-s deprecated, use -o soft\n");
405 			build_iovec(&iov, &iovlen, "soft", NULL, 0);
406 			softintr = true;
407 			break;
408 		case 'T':
409 			nfsproto = IPPROTO_TCP;
410 			printf("-T deprecated, use -o tcp\n");
411 			break;
412 		case 't':
413 			printf("-t deprecated, use -o timeout=<value>\n");
414 			build_iovec(&iov, &iovlen, "timeout", optarg, (size_t)-1);
415 			break;
416 		case 'w':
417 			printf("-w deprecated, use -o wsize=<value>\n");
418 			build_iovec(&iov, &iovlen, "wsize", optarg, (size_t)-1);
419 			break;
420 		case 'x':
421 			printf("-x deprecated, use -o retrans=<value>\n");
422 			build_iovec(&iov, &iovlen, "retrans", optarg, (size_t)-1);
423 			break;
424 		case 'U':
425 			printf("-U deprecated, use -o mntudp\n");
426 			mnttcp_ok = 0;
427 			nfsproto = IPPROTO_UDP;
428 			build_iovec(&iov, &iovlen, "mntudp", NULL, 0);
429 			break;
430 		default:
431 			usage();
432 			break;
433 		}
434 	argc -= optind;
435 	argv += optind;
436 
437 	if ((opflags & (BGRND | BGRNDNOW)) == (BGRND | BGRNDNOW))
438 		errx(1, "Options bg and bgnow are mutually exclusive");
439 
440 	if (argc != 2) {
441 		usage();
442 		/* NOTREACHED */
443 	}
444 
445 	/* Warn that NFSv4 mounts only work correctly as hard mounts. */
446 	if (mountmode == V4 && softintr)
447 		warnx("Warning, options soft and/or intr cannot be safely used"
448 		    " for NFSv4. See the BUGS section of mount_nfs(8)");
449 
450 	spec = *argv++;
451 	mntname = *argv;
452 
453 	if (retrycnt == -1)
454 		/* The default is to keep retrying forever. */
455 		retrycnt = 0;
456 
457 	if (modfind("nfscl") < 0) {
458 		/* Not present in kernel, try loading it */
459 		if (kldload("nfscl") < 0 ||
460 		    modfind("nfscl") < 0)
461 			errx(1, "nfscl is not available");
462 	}
463 
464 	/*
465 	 * Add the fqdn to the gssname, as required.
466 	 */
467 	if (gssname != NULL) {
468 		if (strchr(gssname, '@') == NULL &&
469 		    gethostname(hostname, MAXHOSTNAMELEN) == 0) {
470 			snprintf(gssn, sizeof (gssn), "%s@%s", gssname,
471 			    hostname);
472 			gssname = gssn;
473 		}
474 		build_iovec(&iov, &iovlen, "gssname",
475 		    __DECONST(void *, gssname), strlen(gssname) + 1);
476 	}
477 
478 	if (!getnfsargs(&spec, &host, &iov, &iovlen))
479 		exit(1);
480 
481 	/* resolve the mountpoint with realpath(3) */
482 	if (checkpath(mntname, mntpath) != 0)
483 		err(1, "%s", mntpath);
484 
485 	build_iovec_argf(&iov, &iovlen, "fstype", "nfs");
486 	build_iovec(&iov, &iovlen, "fspath", mntpath, (size_t)-1);
487 	build_iovec(&iov, &iovlen, "errmsg", errmsg, sizeof(errmsg));
488 
489 	if (nmount(iov, iovlen, 0)) {
490 		nmount_errstr = nfsv4_geterrstr(errno);
491 		if (mountmode == V4 && nmount_errstr != NULL)
492 			errx(1, "nmount: %s, %s", mntpath, nmount_errstr);
493 		else
494 			err(1, "nmount: %s%s%s", mntpath, errmsg[0] ? ", " : "",
495 			    errmsg);
496 	} else if (mountmode != V4 && !add_mtab(host, spec)) {
497 		/* Add mounted file system to PATH_MOUNTTAB */
498 		warnx("can't update %s for %s:%s", PATH_MOUNTTAB, host, spec);
499 	}
500 
501 	exit(0);
502 }
503 
504 static int
505 sec_name_to_num(const char *sec)
506 {
507 	if (!strcmp(sec, "krb5"))
508 		return (RPCSEC_GSS_KRB5);
509 	if (!strcmp(sec, "krb5i"))
510 		return (RPCSEC_GSS_KRB5I);
511 	if (!strcmp(sec, "krb5p"))
512 		return (RPCSEC_GSS_KRB5P);
513 	if (!strcmp(sec, "sys"))
514 		return (AUTH_SYS);
515 	return (-1);
516 }
517 
518 static const char *
519 sec_num_to_name(int flavor)
520 {
521 	switch (flavor) {
522 	case RPCSEC_GSS_KRB5:
523 		return ("krb5");
524 	case RPCSEC_GSS_KRB5I:
525 		return ("krb5i");
526 	case RPCSEC_GSS_KRB5P:
527 		return ("krb5p");
528 	case AUTH_SYS:
529 		return ("sys");
530 	}
531 	return (NULL);
532 }
533 
534 /*
535  * Wait for RTM_IFINFO message with interface that is IFF_UP and with
536  * link on, or until timeout expires.  Returns seconds left.
537  */
538 static time_t
539 rtm_ifinfo_sleep(time_t sec)
540 {
541 	char buf[2048] __aligned(__alignof(struct if_msghdr));
542 	fd_set rfds;
543 	struct timeval tv, start;
544 	ssize_t nread;
545 	int n, s;
546 
547 	s = socket(PF_ROUTE, SOCK_RAW, 0);
548 	if (s < 0)
549 		err(EX_OSERR, "socket");
550 	(void)gettimeofday(&start, NULL);
551 
552 	for (tv.tv_sec = sec, tv.tv_usec = 0;
553 	    tv.tv_sec > 0;
554 	    (void)gettimeofday(&tv, NULL),
555 	    tv.tv_sec = sec - (tv.tv_sec - start.tv_sec)) {
556 		FD_ZERO(&rfds);
557 		FD_SET(s, &rfds);
558 		n = select(s + 1, &rfds, NULL, NULL, &tv);
559 		if (n == 0)
560 			continue;
561 		if (n == -1) {
562 			if (errno == EINTR)
563 				continue;
564 			else
565 				err(EX_SOFTWARE, "select");
566 		}
567 		nread = read(s, buf, 2048);
568 		if (nread < 0)
569 			err(EX_OSERR, "read");
570 		if ((size_t)nread >= sizeof(struct if_msghdr)) {
571 			struct if_msghdr *ifm;
572 
573 			ifm = (struct if_msghdr *)buf;
574 			if (ifm->ifm_version == RTM_VERSION &&
575 			    ifm->ifm_type == RTM_IFINFO &&
576 			    (ifm->ifm_flags & IFF_UP) &&
577 			    ifm->ifm_data.ifi_link_state != LINK_STATE_DOWN)
578 				break;
579 		}
580 	}
581 
582 	close(s);
583 
584 	return (tv.tv_sec);
585 }
586 
587 static int
588 getnfsargs(char **specp, char **hostpp, struct iovec **iov, int *iovlen)
589 {
590 	struct addrinfo hints, *ai_nfs, *ai;
591 	enum tryret ret;
592 	int ecode, speclen, remoteerr, offset, have_bracket = 0;
593 	char *hostp, *delimp, *errstr, *spec;
594 	size_t len;
595 	static char nam[MNAMELEN + 1], pname[MAXHOSTNAMELEN + 5];
596 
597 	spec = *specp;
598 	if (*spec == '[' && (delimp = strchr(spec + 1, ']')) != NULL &&
599 	    *(delimp + 1) == ':') {
600 		hostp = spec + 1;
601 		spec = delimp + 2;
602 		have_bracket = 1;
603 	} else if ((delimp = strrchr(spec, ':')) != NULL) {
604 		hostp = spec;
605 		spec = delimp + 1;
606 	} else if ((delimp = strrchr(spec, '@')) != NULL) {
607 		warnx("path@server syntax is deprecated, use server:path");
608 		hostp = delimp + 1;
609 	} else {
610 		warnx("no <host>:<dirpath> nfs-name");
611 		return (0);
612 	}
613 	*delimp = '\0';
614 
615 	/*
616 	 * If there has been a trailing slash at mounttime it seems
617 	 * that some mountd implementations fail to remove the mount
618 	 * entries from their mountlist while unmounting.
619 	 */
620 	for (speclen = strlen(spec);
621 		speclen > 1 && spec[speclen - 1] == '/';
622 		speclen--)
623 		spec[speclen - 1] = '\0';
624 	if (strlen(hostp) + strlen(spec) + 1 > MNAMELEN) {
625 		warnx("%s:%s: %s", hostp, spec, strerror(ENAMETOOLONG));
626 		return (0);
627 	}
628 	/* Make both '@' and ':' notations equal */
629 	if (*hostp != '\0') {
630 		len = strlen(hostp);
631 		offset = 0;
632 		if (have_bracket)
633 			nam[offset++] = '[';
634 		memmove(nam + offset, hostp, len);
635 		if (have_bracket)
636 			nam[len + offset++] = ']';
637 		nam[len + offset++] = ':';
638 		memmove(nam + len + offset, spec, speclen);
639 		nam[len + speclen + offset] = '\0';
640 	}
641 
642 	/*
643 	 * Handle an internet host address.
644 	 */
645 	memset(&hints, 0, sizeof hints);
646 	hints.ai_flags = AI_NUMERICHOST;
647 	if (nfsproto == IPPROTO_TCP)
648 		hints.ai_socktype = SOCK_STREAM;
649 	else if (nfsproto == IPPROTO_UDP)
650 		hints.ai_socktype = SOCK_DGRAM;
651 
652 	if (getaddrinfo(hostp, portspec, &hints, &ai_nfs) != 0) {
653 		hints.ai_flags = AI_CANONNAME;
654 		if ((ecode = getaddrinfo(hostp, portspec, &hints, &ai_nfs))
655 		    != 0) {
656 			if (portspec == NULL)
657 				errx(1, "%s: %s", hostp, gai_strerror(ecode));
658 			else
659 				errx(1, "%s:%s: %s", hostp, portspec,
660 				    gai_strerror(ecode));
661 			return (0);
662 		}
663 
664 		/*
665 		 * For a Kerberized nfs mount where the "principal"
666 		 * argument has not been set, add it here.
667 		 */
668 		if (got_principal == 0 && secflavor != AUTH_SYS &&
669 		    ai_nfs->ai_canonname != NULL) {
670 			snprintf(pname, sizeof (pname), "nfs@%s",
671 			    ai_nfs->ai_canonname);
672 			build_iovec(iov, iovlen, "principal", pname,
673 			    strlen(pname) + 1);
674 		}
675 	}
676 
677 	if ((opflags & (BGRNDNOW | ISBGRND)) == BGRNDNOW) {
678 		warnx("Mount %s:%s, backgrounding",
679 		    hostp, spec);
680 		opflags |= ISBGRND;
681 		if (daemon(0, 0) != 0)
682 			err(1, "daemon");
683 	}
684 
685 	ret = TRYRET_LOCALERR;
686 	for (;;) {
687 		/*
688 		 * Try each entry returned by getaddrinfo(). Note the
689 		 * occurrence of remote errors by setting `remoteerr'.
690 		 */
691 		remoteerr = 0;
692 		for (ai = ai_nfs; ai != NULL; ai = ai->ai_next) {
693 			if ((ai->ai_family == AF_INET6) &&
694 			    (opflags & OF_NOINET6))
695 				continue;
696 			if ((ai->ai_family == AF_INET) &&
697 			    (opflags & OF_NOINET4))
698 				continue;
699 			ret = nfs_tryproto(ai, hostp, spec, &errstr, iov,
700 			    iovlen);
701 			if (ret == TRYRET_SUCCESS)
702 				break;
703 			if (ret != TRYRET_LOCALERR)
704 				remoteerr = 1;
705 			if ((opflags & ISBGRND) == 0)
706 				fprintf(stderr, "%s\n", errstr);
707 		}
708 		if (ret == TRYRET_SUCCESS)
709 			break;
710 
711 		/* Exit if all errors were local. */
712 		if (!remoteerr)
713 			exit(1);
714 
715 		/*
716 		 * If retrycnt == 0, we are to keep retrying forever.
717 		 * Otherwise decrement it, and exit if it hits zero.
718 		 */
719 		if (retrycnt != 0 && --retrycnt == 0)
720 			exit(1);
721 
722 		if ((opflags & (BGRND | ISBGRND)) == BGRND) {
723 			warnx("Cannot immediately mount %s:%s, backgrounding",
724 			    hostp, spec);
725 			opflags |= ISBGRND;
726 			if (daemon(0, 0) != 0)
727 				err(1, "daemon");
728 		}
729 		/*
730 		 * If rtm_ifinfo_sleep() returns non-zero, don't count
731 		 * that as a retry attempt.
732 		 */
733 		if (rtm_ifinfo_sleep(60) && retrycnt != 0)
734 			retrycnt++;
735 	}
736 	freeaddrinfo(ai_nfs);
737 
738 	build_iovec(iov, iovlen, "hostname", nam, (size_t)-1);
739 
740 	*specp = spec;
741 	*hostpp = hostp;
742 	return (1);
743 }
744 
745 /*
746  * Try to set up the NFS arguments according to the address
747  * family, protocol (and possibly port) specified in `ai'.
748  *
749  * Returns TRYRET_SUCCESS if successful, or:
750  *   TRYRET_TIMEOUT		The server did not respond.
751  *   TRYRET_REMOTEERR		The server reported an error.
752  *   TRYRET_LOCALERR		Local failure.
753  *
754  * In all error cases, *errstr will be set to a statically-allocated string
755  * describing the error.
756  */
757 static enum tryret
758 nfs_tryproto(struct addrinfo *ai, char *hostp, char *spec, char **errstr,
759     struct iovec **iov, int *iovlen)
760 {
761 	static char errbuf[256];
762 	struct sockaddr_storage nfs_ss;
763 	struct netbuf nfs_nb;
764 	struct nfhret nfhret;
765 	struct timeval try;
766 	struct rpc_err rpcerr;
767 	CLIENT *clp;
768 	struct netconfig *nconf, *nconf_mnt;
769 	const char *netid, *netid_mnt, *secname;
770 	int doconnect, nfsvers, mntvers, sotype;
771 	enum clnt_stat clntstat;
772 	enum mountmode trymntmode;
773 
774 	sotype = 0;
775 	trymntmode = mountmode;
776 	errbuf[0] = '\0';
777 	*errstr = errbuf;
778 
779 	if (nfsproto == IPPROTO_TCP)
780 		sotype = SOCK_STREAM;
781 	else if (nfsproto == IPPROTO_UDP)
782 		sotype = SOCK_DGRAM;
783 
784 	if ((netid = netidbytype(ai->ai_family, sotype)) == NULL) {
785 		snprintf(errbuf, sizeof errbuf,
786 		    "af %d sotype %d not supported", ai->ai_family, sotype);
787 		return (TRYRET_LOCALERR);
788 	}
789 	if ((nconf = getnetconf_cached(netid)) == NULL) {
790 		snprintf(errbuf, sizeof errbuf, "%s: %s", netid, nc_sperror());
791 		return (TRYRET_LOCALERR);
792 	}
793 	/* The RPCPROG_MNT netid may be different. */
794 	if (mnttcp_ok) {
795 		netid_mnt = netid;
796 		nconf_mnt = nconf;
797 	} else {
798 		if ((netid_mnt = netidbytype(ai->ai_family, SOCK_DGRAM))
799 		     == NULL) {
800 			snprintf(errbuf, sizeof errbuf,
801 			    "af %d sotype SOCK_DGRAM not supported",
802 			     ai->ai_family);
803 			return (TRYRET_LOCALERR);
804 		}
805 		if ((nconf_mnt = getnetconf_cached(netid_mnt)) == NULL) {
806 			snprintf(errbuf, sizeof errbuf, "%s: %s", netid_mnt,
807 			    nc_sperror());
808 			return (TRYRET_LOCALERR);
809 		}
810 	}
811 
812 tryagain:
813 	if (trymntmode == V4) {
814 		nfsvers = 4;
815 		mntvers = 3; /* Workaround for GCC. */
816 	} else if (trymntmode == V2) {
817 		nfsvers = 2;
818 		mntvers = 1;
819 	} else {
820 		nfsvers = 3;
821 		mntvers = 3;
822 	}
823 
824 	if (portspec != NULL) {
825 		/* `ai' contains the complete nfsd sockaddr. */
826 		nfs_nb.buf = ai->ai_addr;
827 		nfs_nb.len = nfs_nb.maxlen = ai->ai_addrlen;
828 	} else {
829 		/* Ask the remote rpcbind. */
830 		nfs_nb.buf = &nfs_ss;
831 		nfs_nb.len = nfs_nb.maxlen = sizeof nfs_ss;
832 
833 		if (!rpcb_getaddr(NFS_PROGRAM, nfsvers, nconf, &nfs_nb,
834 		    hostp)) {
835 			if (rpc_createerr.cf_stat == RPC_PROGVERSMISMATCH &&
836 			    trymntmode == ANY) {
837 				trymntmode = V2;
838 				goto tryagain;
839 			}
840 			snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s",
841 			    netid, hostp, spec,
842 			    clnt_spcreateerror("RPCPROG_NFS"));
843 			return (returncode(rpc_createerr.cf_stat,
844 			    &rpc_createerr.cf_error));
845 		}
846 	}
847 
848 	/* Check that the server (nfsd) responds on the port we have chosen. */
849 	clp = clnt_tli_create(RPC_ANYFD, nconf, &nfs_nb, NFS_PROGRAM, nfsvers,
850 	    0, 0);
851 	if (clp == NULL) {
852 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid,
853 		    hostp, spec, clnt_spcreateerror("nfsd: RPCPROG_NFS"));
854 		return (returncode(rpc_createerr.cf_stat,
855 		    &rpc_createerr.cf_error));
856 	}
857 	if (sotype == SOCK_DGRAM && noconn == 0) {
858 		/*
859 		 * Use connect(), to match what the kernel does. This
860 		 * catches cases where the server responds from the
861 		 * wrong source address.
862 		 */
863 		doconnect = 1;
864 		if (!clnt_control(clp, CLSET_CONNECT, (char *)&doconnect)) {
865 			clnt_destroy(clp);
866 			snprintf(errbuf, sizeof errbuf,
867 			    "[%s] %s:%s: CLSET_CONNECT failed", netid, hostp,
868 			    spec);
869 			return (TRYRET_LOCALERR);
870 		}
871 	}
872 
873 	try.tv_sec = 10;
874 	try.tv_usec = 0;
875 	clntstat = clnt_call(clp, NFSPROC_NULL, (xdrproc_t)xdr_void, NULL,
876 			 (xdrproc_t)xdr_void, NULL, try);
877 	if (clntstat != RPC_SUCCESS) {
878 		if (clntstat == RPC_PROGVERSMISMATCH && trymntmode == ANY) {
879 			clnt_destroy(clp);
880 			trymntmode = V2;
881 			goto tryagain;
882 		}
883 		clnt_geterr(clp, &rpcerr);
884 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid,
885 		    hostp, spec, clnt_sperror(clp, "NFSPROC_NULL"));
886 		clnt_destroy(clp);
887 		return (returncode(clntstat, &rpcerr));
888 	}
889 	clnt_destroy(clp);
890 
891 	/*
892 	 * For NFSv4, there is no mount protocol.
893 	 */
894 	if (trymntmode == V4) {
895 		/*
896 		 * Store the server address in nfsargsp, making
897 		 * sure to copy any locally allocated structures.
898 		 */
899 		addrlen = nfs_nb.len;
900 		addr = malloc(addrlen);
901 		if (addr == NULL)
902 			err(1, "malloc");
903 		bcopy(nfs_nb.buf, addr, addrlen);
904 
905 		build_iovec(iov, iovlen, "addr", addr, addrlen);
906 		secname = sec_num_to_name(secflavor);
907 		if (secname != NULL) {
908 			build_iovec(iov, iovlen, "sec",
909 			    __DECONST(void *, secname), (size_t)-1);
910 		}
911 		build_iovec(iov, iovlen, "nfsv4", NULL, 0);
912 		build_iovec(iov, iovlen, "dirpath", spec, (size_t)-1);
913 
914 		return (TRYRET_SUCCESS);
915 	}
916 
917 	/* Send the MOUNTPROC_MNT RPC to get the root filehandle. */
918 	try.tv_sec = 10;
919 	try.tv_usec = 0;
920 	clp = clnt_tp_create(hostp, MOUNTPROG, mntvers, nconf_mnt);
921 	if (clp == NULL) {
922 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid_mnt,
923 		    hostp, spec, clnt_spcreateerror("RPCMNT: clnt_create"));
924 		return (returncode(rpc_createerr.cf_stat,
925 		    &rpc_createerr.cf_error));
926 	}
927 	clp->cl_auth = authsys_create_default();
928 	nfhret.auth = secflavor;
929 	nfhret.vers = mntvers;
930 	clntstat = clnt_call(clp, MOUNTPROC_MNT, (xdrproc_t)xdr_dir, spec,
931 			 (xdrproc_t)xdr_fh, &nfhret,
932 	    try);
933 	auth_destroy(clp->cl_auth);
934 	if (clntstat != RPC_SUCCESS) {
935 		if (clntstat == RPC_PROGVERSMISMATCH && trymntmode == ANY) {
936 			clnt_destroy(clp);
937 			trymntmode = V2;
938 			goto tryagain;
939 		}
940 		clnt_geterr(clp, &rpcerr);
941 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid_mnt,
942 		    hostp, spec, clnt_sperror(clp, "RPCPROG_MNT"));
943 		clnt_destroy(clp);
944 		return (returncode(clntstat, &rpcerr));
945 	}
946 	clnt_destroy(clp);
947 
948 	if (nfhret.stat != 0) {
949 		snprintf(errbuf, sizeof errbuf, "[%s] %s:%s: %s", netid_mnt,
950 		    hostp, spec, strerror(nfhret.stat));
951 		return (TRYRET_REMOTEERR);
952 	}
953 
954 	/*
955 	 * Store the filehandle and server address in nfsargsp, making
956 	 * sure to copy any locally allocated structures.
957 	 */
958 	addrlen = nfs_nb.len;
959 	addr = malloc(addrlen);
960 	fhsize = nfhret.fhsize;
961 	fh = malloc(fhsize);
962 	if (addr == NULL || fh == NULL)
963 		err(1, "malloc");
964 	bcopy(nfs_nb.buf, addr, addrlen);
965 	bcopy(nfhret.nfh, fh, fhsize);
966 
967 	build_iovec(iov, iovlen, "addr", addr, addrlen);
968 	build_iovec(iov, iovlen, "fh", fh, fhsize);
969 	secname = sec_num_to_name(nfhret.auth);
970 	if (secname) {
971 		build_iovec(iov, iovlen, "sec",
972 		    __DECONST(void *, secname), (size_t)-1);
973 	}
974 	if (nfsvers == 3)
975 		build_iovec(iov, iovlen, "nfsv3", NULL, 0);
976 
977 	return (TRYRET_SUCCESS);
978 }
979 
980 /*
981  * Catagorise a RPC return status and error into an `enum tryret'
982  * return code.
983  */
984 static enum tryret
985 returncode(enum clnt_stat clntstat, struct rpc_err *rpcerr)
986 {
987 
988 	switch (clntstat) {
989 	case RPC_TIMEDOUT:
990 		return (TRYRET_TIMEOUT);
991 	case RPC_PMAPFAILURE:
992 	case RPC_PROGNOTREGISTERED:
993 	case RPC_PROGVERSMISMATCH:
994 	/* XXX, these can be local or remote. */
995 	case RPC_CANTSEND:
996 	case RPC_CANTRECV:
997 		return (TRYRET_REMOTEERR);
998 	case RPC_SYSTEMERROR:
999 		switch (rpcerr->re_errno) {
1000 		case ETIMEDOUT:
1001 			return (TRYRET_TIMEOUT);
1002 		case ENOMEM:
1003 			break;
1004 		default:
1005 			return (TRYRET_REMOTEERR);
1006 		}
1007 		/* FALLTHROUGH */
1008 	default:
1009 		break;
1010 	}
1011 	return (TRYRET_LOCALERR);
1012 }
1013 
1014 /*
1015  * Look up a netid based on an address family and socket type.
1016  * `af' is the address family, and `sotype' is SOCK_DGRAM or SOCK_STREAM.
1017  *
1018  * XXX there should be a library function for this.
1019  */
1020 static const char *
1021 netidbytype(int af, int sotype)
1022 {
1023 	struct nc_protos *p;
1024 
1025 	for (p = nc_protos; p->netid != NULL; p++) {
1026 		if (af != p->af || sotype != p->sotype)
1027 			continue;
1028 		return (p->netid);
1029 	}
1030 	return (NULL);
1031 }
1032 
1033 /*
1034  * Look up a netconfig entry based on a netid, and cache the result so
1035  * that we don't need to remember to call freenetconfigent().
1036  *
1037  * Otherwise it behaves just like getnetconfigent(), so nc_*error()
1038  * work on failure.
1039  */
1040 static struct netconfig *
1041 getnetconf_cached(const char *netid)
1042 {
1043 	static struct nc_entry {
1044 		struct netconfig *nconf;
1045 		struct nc_entry *next;
1046 	} *head;
1047 	struct nc_entry *p;
1048 	struct netconfig *nconf;
1049 
1050 	for (p = head; p != NULL; p = p->next)
1051 		if (strcmp(netid, p->nconf->nc_netid) == 0)
1052 			return (p->nconf);
1053 
1054 	if ((nconf = getnetconfigent(netid)) == NULL)
1055 		return (NULL);
1056 	if ((p = malloc(sizeof(*p))) == NULL)
1057 		err(1, "malloc");
1058 	p->nconf = nconf;
1059 	p->next = head;
1060 	head = p;
1061 
1062 	return (p->nconf);
1063 }
1064 
1065 /*
1066  * xdr routines for mount rpc's
1067  */
1068 static int
1069 xdr_dir(XDR *xdrsp, char *dirp)
1070 {
1071 	return (xdr_string(xdrsp, &dirp, MNTPATHLEN));
1072 }
1073 
1074 static int
1075 xdr_fh(XDR *xdrsp, struct nfhret *np)
1076 {
1077 	int i;
1078 	long auth, authcnt, authfnd = 0;
1079 
1080 	if (!xdr_u_long(xdrsp, &np->stat))
1081 		return (0);
1082 	if (np->stat)
1083 		return (1);
1084 	switch (np->vers) {
1085 	case 1:
1086 		np->fhsize = NFS_FHSIZE;
1087 		return (xdr_opaque(xdrsp, (caddr_t)np->nfh, NFS_FHSIZE));
1088 	case 3:
1089 		if (!xdr_long(xdrsp, &np->fhsize))
1090 			return (0);
1091 		if (np->fhsize <= 0 || np->fhsize > NFS3_FHSIZE)
1092 			return (0);
1093 		if (!xdr_opaque(xdrsp, (caddr_t)np->nfh, np->fhsize))
1094 			return (0);
1095 		if (!xdr_long(xdrsp, &authcnt))
1096 			return (0);
1097 		for (i = 0; i < authcnt; i++) {
1098 			if (!xdr_long(xdrsp, &auth))
1099 				return (0);
1100 			if (np->auth == -1) {
1101 				np->auth = auth;
1102 				authfnd++;
1103 			} else if (auth == np->auth) {
1104 				authfnd++;
1105 			}
1106 		}
1107 		/*
1108 		 * Some servers, such as DEC's OSF/1 return a nil authenticator
1109 		 * list to indicate RPCAUTH_UNIX.
1110 		 */
1111 		if (authcnt == 0 && np->auth == -1)
1112 			np->auth = AUTH_SYS;
1113 		if (!authfnd && (authcnt > 0 || np->auth != AUTH_SYS))
1114 			np->stat = EAUTH;
1115 		return (1);
1116 	}
1117 	return (0);
1118 }
1119 
1120 static void
1121 usage(void)
1122 {
1123 	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n",
1124 "usage: mount_nfs [-23bcdiLlNPsTU] [-a maxreadahead] [-D deadthresh]",
1125 "                 [-g maxgroups] [-I readdirsize] [-o options] [-R retrycnt]",
1126 "                 [-r readsize] [-t timeout] [-w writesize] [-x retrans]",
1127 "                 rhost:path node");
1128 	exit(1);
1129 }
1130