xref: /netbsd-src/sys/nfs/nfs_boot.c (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /*	$NetBSD: nfs_boot.c,v 1.33 1997/05/27 23:37:39 gwr Exp $	*/
2 
3 /*
4  * Copyright (c) 1995 Adam Glass, Gordon Ross
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the authors may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/conf.h>
34 #include <sys/device.h>
35 #include <sys/ioctl.h>
36 #include <sys/proc.h>
37 #include <sys/mount.h>
38 #include <sys/mbuf.h>
39 #include <sys/reboot.h>
40 #include <sys/socket.h>
41 #include <sys/socketvar.h>
42 
43 #include <net/if.h>
44 #include <net/route.h>
45 
46 #include <net/if_ether.h>
47 
48 #include <netinet/in.h>
49 #include <netinet/if_inarp.h>
50 
51 #include <nfs/rpcv2.h>
52 #include <nfs/nfsproto.h>
53 #include <nfs/nfs.h>
54 #include <nfs/nfsdiskless.h>
55 #include <nfs/krpc.h>
56 #include <nfs/xdr_subs.h>
57 #include <nfs/nfs_var.h>
58 
59 #include "ether.h"
60 #if NETHER == 0
61 
62 int nfs_boot_init(nd, procp)
63 	struct nfs_diskless *nd;
64 	struct proc *procp;
65 {
66 	printf("nfs_boot: NETHER == 0\n");
67 	return (ENXIO);
68 }
69 
70 int
71 nfs_boot_getfh(ndm)
72 	struct nfs_dlmount *ndm;
73 {
74 	return (ENXIO);
75 }
76 
77 #else /* NETHER */
78 
79 /*
80  * Support for NFS diskless booting, specifically getting information
81  * about where to boot from, what pathnames, etc.
82  *
83  * This implememtation uses RARP and the bootparam RPC.
84  * We are forced to implement RPC anyway (to get file handles)
85  * so we might as well take advantage of it for bootparam too.
86  *
87  * The diskless boot sequence goes as follows:
88  * (1) Use RARP to get our interface address
89  * (2) Use RPC/bootparam/whoami to get our hostname,
90  *     our IP address, and the server's IP address.
91  * (3) Use RPC/bootparam/getfile to get the root path
92  * (4) Use RPC/mountd to get the root file handle
93  * (5) Use RPC/bootparam/getfile to get the swap path
94  * (6) Use RPC/mountd to get the swap file handle
95  *
96  * (This happens to be the way Sun does it too.)
97  */
98 
99 /* bootparam RPC */
100 static int bp_whoami __P((struct sockaddr_in *bpsin,
101 	struct in_addr *my_ip, struct in_addr *gw_ip));
102 static int bp_getfile __P((struct sockaddr_in *bpsin, char *key,
103 	struct nfs_dlmount *ndm));
104 
105 /* mountd RPC */
106 static int md_mount __P((struct sockaddr_in *mdsin, char *path,
107 	struct nfs_args *argp));
108 
109 /*
110  * Called with an empty nfs_diskless struct to be filled in.
111  */
112 int
113 nfs_boot_init(nd, procp)
114 	struct nfs_diskless *nd;
115 	struct proc *procp;
116 {
117 	struct ifreq ireq;
118 	struct in_addr my_ip, gw_ip;
119 	struct sockaddr_in bp_sin;
120 	struct sockaddr_in *sin;
121 	struct ifnet *ifp;
122 	struct socket *so;
123 	int error;
124 
125 	/*
126 	 * Find an interface, rarp for its ip address, stuff it, the
127 	 * implied broadcast addr, and netmask into a nfs_diskless struct.
128 	 *
129 	 * This was moved here from nfs_vfsops.c because this procedure
130 	 * would be quite different if someone decides to write (i.e.) a
131 	 * BOOTP version of this file (might not use RARP, etc.)
132 	 */
133 
134 	/*
135 	 * Find a network interface.
136 	 */
137 	ifp = ifunit(root_device->dv_xname);
138 	if (ifp == NULL) {
139 		printf("nfs_boot: no suitable interface\n");
140 		return (ENXIO);
141 	}
142 	bcopy(ifp->if_xname, ireq.ifr_name, IFNAMSIZ);
143 	printf("nfs_boot: using network interface '%s'\n",
144 	    ireq.ifr_name);
145 
146 	/*
147 	 * Bring up the interface.
148 	 *
149 	 * Get the old interface flags and or IFF_UP into them; if
150 	 * IFF_UP set blindly, interface selection can be clobbered.
151 	 */
152 	so = 0;
153 	error = socreate(AF_INET, &so, SOCK_DGRAM, 0);
154 	if (error) {
155 		printf("nfs_boot: socreate, error=%d\n", error);
156 		so = 0;
157 		goto out;
158 	}
159 	error = ifioctl(so, SIOCGIFFLAGS, (caddr_t)&ireq, procp);
160 	if (error) {
161 		printf("nfs_boot: GIFFLAGS, error=%d\n", error);
162 		goto out;
163 	}
164 	ireq.ifr_flags |= IFF_UP;
165 	error = ifioctl(so, SIOCSIFFLAGS, (caddr_t)&ireq, procp);
166 	if (error) {
167 		printf("nfs_boot: SIFFLAGS, error=%d\n", error);
168 		goto out;
169 	}
170 
171 	/*
172 	 * Do RARP for the interface address.
173 	 */
174 	if ((error = revarpwhoami(&my_ip, ifp)) != 0) {
175 		printf("revarp failed, error=%d\n", error);
176 		error = EIO;	/* XXX */
177 		goto out;
178 	}
179 	printf("nfs_boot: client_addr=0x%x\n",
180 	       (u_int32_t)ntohl(my_ip.s_addr));
181 
182 	/*
183 	 * Do enough of ifconfig(8) so that the chosen interface
184 	 * can talk to the servers.  (just set the address)
185 	 */
186 	sin = (struct sockaddr_in *)&ireq.ifr_addr;
187 	bzero((caddr_t)sin, sizeof(*sin));
188 	sin->sin_len = sizeof(*sin);
189 	sin->sin_family = AF_INET;
190 	sin->sin_addr.s_addr = my_ip.s_addr;
191 	error = ifioctl(so, SIOCSIFADDR, (caddr_t)&ireq, procp);
192 	if (error) {
193 		printf("nfs_boot: set if addr, error=%d\n", error);
194 		goto out;
195 	}
196 
197 	/*
198 	 * Get client name and gateway address.
199 	 * RPC: bootparam/whoami
200 	 * Use the old broadcast address for the WHOAMI
201 	 * call because we do not yet know our netmask.
202 	 * The server address returned by the WHOAMI call
203 	 * is used for all subsequent booptaram RPCs.
204 	 */
205 	bzero((caddr_t)&bp_sin, sizeof(bp_sin));
206 	bp_sin.sin_len = sizeof(bp_sin);
207 	bp_sin.sin_family = AF_INET;
208 	bp_sin.sin_addr.s_addr = INADDR_BROADCAST;
209 	hostnamelen = MAXHOSTNAMELEN;
210 
211 	/* Do the RPC/bootparam/whoami. */
212 	error = bp_whoami(&bp_sin, &my_ip, &gw_ip);
213 	if (error) {
214 		printf("nfs_boot: bootparam whoami, error=%d\n", error);
215 		goto out;
216 	}
217 	printf("nfs_boot: server_addr=0x%x\n",
218 		   (u_int32_t)ntohl(bp_sin.sin_addr.s_addr));
219 	printf("nfs_boot: hostname=%s\n", hostname);
220 
221 #ifdef	NFS_BOOT_GATEWAY
222 	/*
223 	 * XXX - This code is conditionally compiled only because
224 	 * many bootparam servers (in particular, SunOS 4.1.3)
225 	 * always set the gateway address to their own address.
226 	 * The bootparam server is not necessarily the gateway.
227 	 * We could just believe the server, and at worst you would
228 	 * need to delete the incorrect default route before adding
229 	 * the correct one, but for simplicity, ignore the gateway.
230 	 * If your server is OK, you can turn on this option.
231 	 *
232 	 * If the gateway address is set, add a default route.
233 	 * (The mountd RPCs may go across a gateway.)
234 	 */
235 	if (gw_ip.s_addr) {
236 		struct sockaddr dst, gw, mask;
237 		/* Destination: (default) */
238 		bzero((caddr_t)&dst, sizeof(dst));
239 		dst.sa_len = sizeof(dst);
240 		dst.sa_family = AF_INET;
241 		/* Gateway: */
242 		bzero((caddr_t)&gw, sizeof(gw));
243 		sin = (struct sockaddr_in *)&gw;
244 		sin->sin_len = sizeof(gw);
245 		sin->sin_family = AF_INET;
246 		sin->sin_addr.s_addr = gw_ip.s_addr;
247 		/* Mask: (zero length) */
248 		bzero(&mask, sizeof(mask));
249 
250 		printf("nfs_boot: gateway=0x%x\n", ntohl(gw_ip.s_addr));
251 		/* add, dest, gw, mask, flags, 0 */
252 		error = rtrequest(RTM_ADD, &dst, (struct sockaddr *)&gw,
253 		    &mask, (RTF_UP | RTF_GATEWAY | RTF_STATIC), NULL);
254 		if (error)
255 			printf("nfs_boot: add route, error=%d\n", error);
256 	}
257 #endif
258 
259 	bcopy(&bp_sin, &nd->nd_boot, sizeof(bp_sin));
260 
261 	/*
262 	 * Now fetch the server:pathname strings and server IP
263 	 * for root and swap.  Missing swap is not fatal.
264 	 */
265 	error = bp_getfile(&nd->nd_boot, "root", &nd->nd_root);
266 	if (error) {
267 		printf("nfs_boot: bootparam get root: %d\n", error);
268 		goto out;
269 	}
270 
271 	error = bp_getfile(&nd->nd_boot, "swap", &nd->nd_swap);
272 	if (error) {
273 		printf("nfs_boot: bootparam get swap: %d", error);
274 		error = 0;
275 	}
276 
277  out:
278 	if (so) soclose(so);
279 
280 	return (error);
281 }
282 
283 int
284 nfs_boot_getfh(ndm)
285 	struct nfs_dlmount *ndm;	/* output */
286 {
287 	struct nfs_args *args;
288 	struct sockaddr_in *sin;
289 	char *pathname;
290 	int error;
291 
292 	args = &ndm->ndm_args;
293 
294 	/* Initialize mount args. */
295 	bzero((caddr_t) args, sizeof(*args));
296 	args->addr     = &ndm->ndm_saddr;
297 	args->addrlen  = args->addr->sa_len;
298 #ifdef NFS_BOOT_TCP
299 	args->sotype   = SOCK_STREAM;
300 #else
301 	args->sotype   = SOCK_DGRAM;
302 #endif
303 	args->fh       = ndm->ndm_fh;
304 	args->hostname = ndm->ndm_host;
305 	args->flags    = NFSMNT_RESVPORT | NFSMNT_NFSV3;
306 
307 #ifdef	NFS_BOOT_OPTIONS
308 	args->flags    |= NFS_BOOT_OPTIONS;
309 #endif
310 #ifdef	NFS_BOOT_RWSIZE
311 	/*
312 	 * Reduce rsize,wsize for interfaces that consistently
313 	 * drop fragments of long UDP messages.  (i.e. wd8003).
314 	 * You can always change these later via remount.
315 	 */
316 	args->flags   |= NFSMNT_WSIZE | NFSMNT_RSIZE;
317 	args->wsize    = NFS_BOOT_RWSIZE;
318 	args->rsize    = NFS_BOOT_RWSIZE;
319 #endif
320 
321 	/*
322 	 * Find the pathname part of the "server:pathname"
323 	 * string left in ndm->ndm_host by nfs_boot_init.
324 	 */
325 	pathname = strchr(ndm->ndm_host, ':');
326 	if (pathname == 0) {
327 		printf("nfs_boot: getfh - no pathname\n");
328 		return (EIO);
329 	}
330 	pathname++;
331 
332 	/*
333 	 * Get file handle using RPC to mountd/mount
334 	 */
335 	sin = (struct sockaddr_in *)&ndm->ndm_saddr;
336 	error = md_mount(sin, pathname, args);
337 	if (error) {
338 		printf("nfs_boot: mountd `%s', error=%d\n",
339 		    ndm->ndm_host, error);
340 		return (error);
341 	}
342 
343 	/* Set port number for NFS use. */
344 	/* XXX: NFS port is always 2049, right? */
345 #ifdef NFS_BOOT_TCP
346 retry:
347 #endif
348 	error = krpc_portmap(sin, NFS_PROG,
349 		    (args->flags & NFSMNT_NFSV3) ? NFS_VER3 : NFS_VER2,
350 		    (args->sotype == SOCK_STREAM) ? IPPROTO_TCP : IPPROTO_UDP,
351 		    &sin->sin_port);
352 	if (sin->sin_port == htons(0))
353 		error = EIO;
354 	if (error) {
355 #ifdef NFS_BOOT_TCP
356 		if (args->sotype == SOCK_STREAM) {
357 			args->sotype = SOCK_DGRAM;
358 			goto retry;
359 		}
360 #endif
361 		printf("nfs_boot: portmap NFS, error=%d\n", error);
362 	}
363 
364 	return (error);
365 }
366 
367 
368 /*
369  * RPC: bootparam/whoami
370  * Given client IP address, get:
371  *	client name	(hostname)
372  *	domain name (domainname)
373  *	gateway address
374  *
375  * The hostname and domainname are set here for convenience.
376  *
377  * Note - bpsin is initialized to the broadcast address,
378  * and will be replaced with the bootparam server address
379  * after this call is complete.  Have to use PMAP_PROC_CALL
380  * to make sure we get responses only from a servers that
381  * know about us (don't want to broadcast a getport call).
382  */
383 static int
384 bp_whoami(bpsin, my_ip, gw_ip)
385 	struct sockaddr_in *bpsin;
386 	struct in_addr *my_ip;
387 	struct in_addr *gw_ip;
388 {
389 	/* RPC structures for PMAPPROC_CALLIT */
390 	struct whoami_call {
391 		u_int32_t call_prog;
392 		u_int32_t call_vers;
393 		u_int32_t call_proc;
394 		u_int32_t call_arglen;
395 	} *call;
396 	struct callit_reply {
397 		u_int32_t port;
398 		u_int32_t encap_len;
399 		/* encapsulated data here */
400 	} *reply;
401 
402 	struct mbuf *m, *from;
403 	struct sockaddr_in *sin;
404 	int error, msg_len;
405 	int16_t port;
406 
407 	/*
408 	 * Build request message for PMAPPROC_CALLIT.
409 	 */
410 	m = m_get(M_WAIT, MT_DATA);
411 	call = mtod(m, struct whoami_call *);
412 	m->m_len = sizeof(*call);
413 	call->call_prog = txdr_unsigned(BOOTPARAM_PROG);
414 	call->call_vers = txdr_unsigned(BOOTPARAM_VERS);
415 	call->call_proc = txdr_unsigned(BOOTPARAM_WHOAMI);
416 
417 	/*
418 	 * append encapsulated data (client IP address)
419 	 */
420 	m->m_next = xdr_inaddr_encode(my_ip);
421 	call->call_arglen = txdr_unsigned(m->m_next->m_len);
422 
423 	/* RPC: portmap/callit */
424 	bpsin->sin_port = htons(PMAPPORT);
425 	from = NULL;
426 	error = krpc_call(bpsin, PMAPPROG, PMAPVERS,
427 			PMAPPROC_CALLIT, &m, &from);
428 	if (error)
429 		return error;
430 
431 	/*
432 	 * Parse result message.
433 	 */
434 	if (m->m_len < sizeof(*reply)) {
435 		m = m_pullup(m, sizeof(*reply));
436 		if (m == NULL)
437 			goto bad;
438 	}
439 	reply = mtod(m, struct callit_reply *);
440 	port = fxdr_unsigned(u_int32_t, reply->port);
441 	msg_len = fxdr_unsigned(u_int32_t, reply->encap_len);
442 	m_adj(m, sizeof(*reply));
443 
444 	/*
445 	 * Save bootparam server address
446 	 */
447 	sin = mtod(from, struct sockaddr_in *);
448 	bpsin->sin_port = htons(port);
449 	bpsin->sin_addr.s_addr = sin->sin_addr.s_addr;
450 
451 	/* client name */
452 	hostnamelen = MAXHOSTNAMELEN-1;
453 	m = xdr_string_decode(m, hostname, &hostnamelen);
454 	if (m == NULL)
455 		goto bad;
456 
457 	/* domain name */
458 	domainnamelen = MAXHOSTNAMELEN-1;
459 	m = xdr_string_decode(m, domainname, &domainnamelen);
460 	if (m == NULL)
461 		goto bad;
462 
463 	/* gateway address */
464 	m = xdr_inaddr_decode(m, gw_ip);
465 	if (m == NULL)
466 		goto bad;
467 
468 	/* success */
469 	goto out;
470 
471 bad:
472 	printf("nfs_boot: bootparam_whoami: bad reply\n");
473 	error = EBADRPC;
474 
475 out:
476 	if (from)
477 		m_freem(from);
478 	if (m)
479 		m_freem(m);
480 	return(error);
481 }
482 
483 
484 /*
485  * RPC: bootparam/getfile
486  * Given client name and file "key", get:
487  *	server name
488  *	server IP address
489  *	server pathname
490  */
491 static int
492 bp_getfile(bpsin, key, ndm)
493 	struct sockaddr_in *bpsin;
494 	char *key;
495 	struct nfs_dlmount *ndm;
496 {
497 	char pathname[MNAMELEN];
498 	struct in_addr inaddr;
499 	struct sockaddr_in *sin;
500 	struct mbuf *m;
501 	char *serv_name;
502 	int error, sn_len, path_len;
503 
504 	/*
505 	 * Build request message.
506 	 */
507 
508 	/* client name (hostname) */
509 	m  = xdr_string_encode(hostname, hostnamelen);
510 	if (m == NULL)
511 		return (ENOMEM);
512 
513 	/* key name (root or swap) */
514 	m->m_next = xdr_string_encode(key, strlen(key));
515 	if (m->m_next == NULL)
516 		return (ENOMEM);
517 
518 	/* RPC: bootparam/getfile */
519 	error = krpc_call(bpsin, BOOTPARAM_PROG, BOOTPARAM_VERS,
520 	                  BOOTPARAM_GETFILE, &m, NULL);
521 	if (error)
522 		return error;
523 
524 	/*
525 	 * Parse result message.
526 	 */
527 
528 	/* server name */
529 	serv_name = &ndm->ndm_host[0];
530 	sn_len = sizeof(ndm->ndm_host) - 1;
531 	m = xdr_string_decode(m, serv_name, &sn_len);
532 	if (m == NULL)
533 		goto bad;
534 
535 	/* server IP address (mountd/NFS) */
536 	m = xdr_inaddr_decode(m, &inaddr);
537 	if (m == NULL)
538 		goto bad;
539 
540 	/* server pathname */
541 	path_len = sizeof(pathname) - 1;
542 	m = xdr_string_decode(m, pathname, &path_len);
543 	if (m == NULL)
544 		goto bad;
545 
546 	/*
547 	 * Store the results in the nfs_dlmount.
548 	 * The strings become "server:pathname"
549 	 */
550 	sin = (struct sockaddr_in *) &ndm->ndm_saddr;
551 	bzero((caddr_t)sin, sizeof(*sin));
552 	sin->sin_len = sizeof(*sin);
553 	sin->sin_family = AF_INET;
554 	sin->sin_addr = inaddr;
555 	if ((sn_len + 1 + path_len + 1) > sizeof(ndm->ndm_host)) {
556 		printf("nfs_boot: getfile name too long\n");
557 		error = EIO;
558 		goto out;
559 	}
560 	ndm->ndm_host[sn_len] = ':';
561 	bcopy(pathname, ndm->ndm_host + sn_len + 1, path_len + 1);
562 
563 	/* success */
564 	goto out;
565 
566 bad:
567 	printf("nfs_boot: bootparam_getfile: bad reply\n");
568 	error = EBADRPC;
569 
570 out:
571 	m_freem(m);
572 	return(0);
573 }
574 
575 
576 /*
577  * RPC: mountd/mount
578  * Given a server pathname, get an NFS file handle.
579  * Also, sets sin->sin_port to the NFS service port.
580  */
581 static int
582 md_mount(mdsin, path, argp)
583 	struct sockaddr_in *mdsin;		/* mountd server address */
584 	char *path;
585 	struct nfs_args *argp;
586 {
587 	/* The RPC structures */
588 	struct rdata {
589 		u_int32_t errno;
590 		union {
591 			u_int8_t  v2fh[NFSX_V2FH];
592 			struct {
593 				u_int32_t fhlen;
594 				u_int8_t  fh[1];
595 			} v3fh;
596 		} fh;
597 	} *rdata;
598 	struct mbuf *m;
599 	u_int8_t *fh;
600 	int minlen, error;
601 
602 retry:
603 	/* Get port number for MOUNTD. */
604 	error = krpc_portmap(mdsin, RPCPROG_MNT,
605 		     (argp->flags & NFSMNT_NFSV3) ? RPCMNT_VER3 : RPCMNT_VER1,
606 		     IPPROTO_UDP, &mdsin->sin_port);
607 	if (error)
608 		return error;
609 
610 	m = xdr_string_encode(path, strlen(path));
611 	if (m == NULL)
612 		return ENOMEM;
613 
614 	/* Do RPC to mountd. */
615 	error = krpc_call(mdsin, RPCPROG_MNT, (argp->flags & NFSMNT_NFSV3) ?
616 			  RPCMNT_VER3 : RPCMNT_VER1, RPCMNT_MOUNT, &m, NULL);
617 	if (error) {
618 		if ((error==RPC_PROGMISMATCH) && (argp->flags & NFSMNT_NFSV3)) {
619 			argp->flags &= ~NFSMNT_NFSV3;
620 			goto retry;
621 		}
622 		return error;	/* message already freed */
623 	}
624 
625 	/* The reply might have only the errno. */
626 	if (m->m_len < 4)
627 		goto bad;
628 	/* Have at least errno, so check that. */
629 	rdata = mtod(m, struct rdata *);
630 	error = fxdr_unsigned(u_int32_t, rdata->errno);
631 	if (error)
632 		goto out;
633 
634 	 /* Have errno==0, so the fh must be there. */
635 	if (argp->flags & NFSMNT_NFSV3){
636 		argp->fhsize   = fxdr_unsigned(u_int32_t, rdata->fh.v3fh.fhlen);
637 		if (argp->fhsize > NFSX_V3FHMAX)
638 			goto bad;
639 		minlen = 2 * sizeof(u_int32_t) + argp->fhsize;
640 	} else {
641 		argp->fhsize   = NFSX_V2FH;
642 		minlen = sizeof(u_int32_t) + argp->fhsize;
643 	}
644 
645 	if (m->m_len < minlen) {
646 		m = m_pullup(m, minlen);
647 		if (m == NULL)
648 			return(EBADRPC);
649 		rdata = mtod(m, struct rdata *);
650 	}
651 
652 	fh = (argp->flags & NFSMNT_NFSV3) ? rdata->fh.v3fh.fh : rdata->fh.v2fh;
653 	bcopy(fh, argp->fh, argp->fhsize);
654 
655 	goto out;
656 
657 bad:
658 	error = EBADRPC;
659 
660 out:
661 	m_freem(m);
662 	return error;
663 }
664 
665 #endif /* NETHER */
666