nfs.c revision 344289 
1/*	$NetBSD: nfs.c,v 1.2 1998/01/24 12:43:09 drochner Exp $	*/
2
3/*-
4 *  Copyright (c) 1993 John Brezak
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 author 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 AUTHOR `AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
22 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
24 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
27 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD: stable/11/stand/libsa/nfs.c 344289 2019-02-19 18:45:40Z kevans $");
33
34#include <sys/param.h>
35#include <sys/time.h>
36#include <sys/socket.h>
37#include <sys/stat.h>
38#include <string.h>
39#include <stddef.h>
40
41#include <netinet/in.h>
42#include <netinet/in_systm.h>
43
44#include "rpcv2.h"
45#include "nfsv2.h"
46
47#include "stand.h"
48#include "net.h"
49#include "netif.h"
50#include "rpc.h"
51
52#define NFS_DEBUGxx
53
54#define NFSREAD_MIN_SIZE 1024
55#define NFSREAD_MAX_SIZE 16384
56
57/* NFSv3 definitions */
58#define	NFS_V3MAXFHSIZE		64
59#define	NFS_VER3		3
60#define	RPCMNT_VER3		3
61#define	NFSPROCV3_LOOKUP	3
62#define	NFSPROCV3_READLINK	5
63#define	NFSPROCV3_READ		6
64#define	NFSPROCV3_READDIR	16
65
66typedef struct {
67	uint32_t val[2];
68} n_quad;
69
70struct nfsv3_time {
71	uint32_t nfs_sec;
72	uint32_t nfs_nsec;
73};
74
75struct nfsv3_fattrs {
76	uint32_t fa_type;
77	uint32_t fa_mode;
78	uint32_t fa_nlink;
79	uint32_t fa_uid;
80	uint32_t fa_gid;
81	n_quad fa_size;
82	n_quad fa_used;
83	n_quad fa_rdev;
84	n_quad fa_fsid;
85	n_quad fa_fileid;
86	struct nfsv3_time fa_atime;
87	struct nfsv3_time fa_mtime;
88	struct nfsv3_time fa_ctime;
89};
90
91/*
92 * For NFSv3, the file handle is variable in size, so most fixed sized
93 * structures for arguments won't work. For most cases, a structure
94 * that starts with any fixed size section is followed by an array
95 * that covers the maximum size required.
96 */
97struct nfsv3_readdir_repl {
98	uint32_t errno;
99	uint32_t ok;
100	struct nfsv3_fattrs fa;
101	uint32_t cookiev0;
102	uint32_t cookiev1;
103};
104
105struct nfsv3_readdir_entry {
106	uint32_t follows;
107	uint32_t fid0;
108	uint32_t fid1;
109	uint32_t len;
110	uint32_t nameplus[0];
111};
112
113struct nfs_iodesc {
114	struct iodesc *iodesc;
115	off_t off;
116	uint32_t fhsize;
117	u_char fh[NFS_V3MAXFHSIZE];
118	struct nfsv3_fattrs fa;	/* all in network order */
119	uint64_t cookie;
120};
121
122/*
123 * XXX interactions with tftp? See nfswrapper.c for a confusing
124 *     issue.
125 */
126int		nfs_open(const char *path, struct open_file *f);
127static int	nfs_close(struct open_file *f);
128static int	nfs_read(struct open_file *f, void *buf, size_t size, size_t *resid);
129static off_t	nfs_seek(struct open_file *f, off_t offset, int where);
130static int	nfs_stat(struct open_file *f, struct stat *sb);
131static int	nfs_readdir(struct open_file *f, struct dirent *d);
132
133struct	nfs_iodesc nfs_root_node;
134
135struct fs_ops nfs_fsops = {
136	"nfs",
137	nfs_open,
138	nfs_close,
139	nfs_read,
140	null_write,
141	nfs_seek,
142	nfs_stat,
143	nfs_readdir
144};
145
146static int nfs_read_size = NFSREAD_MIN_SIZE;
147
148/*
149 * Improve boot performance over NFS
150 */
151static void
152set_nfs_read_size(void)
153{
154	char *env, *end;
155	char buf[10];
156
157	if ((env = getenv("nfs.read_size")) != NULL) {
158		errno = 0;
159		nfs_read_size = (int)strtol(env, &end, 0);
160		if (errno != 0 || *env == '\0' || *end != '\0') {
161			printf("%s: bad value: \"%s\", defaulting to %d\n",
162			    "nfs.read_size", env, NFSREAD_MIN_SIZE);
163			nfs_read_size = NFSREAD_MIN_SIZE;
164		}
165	}
166	if (nfs_read_size < NFSREAD_MIN_SIZE) {
167		printf("%s: bad value: \"%d\", defaulting to %d\n",
168		    "nfs.read_size", nfs_read_size, NFSREAD_MIN_SIZE);
169		nfs_read_size = NFSREAD_MIN_SIZE;
170	}
171	if (nfs_read_size > NFSREAD_MAX_SIZE) {
172		printf("%s: bad value: \"%d\", defaulting to %d\n",
173		    "nfs.read_size", nfs_read_size, NFSREAD_MIN_SIZE);
174		nfs_read_size = NFSREAD_MAX_SIZE;
175	}
176	snprintf(buf, sizeof (buf), "%d", nfs_read_size);
177	setenv("nfs.read_size", buf, 1);
178}
179
180/*
181 * Fetch the root file handle (call mount daemon)
182 * Return zero or error number.
183 */
184int
185nfs_getrootfh(struct iodesc *d, char *path, uint32_t *fhlenp, u_char *fhp)
186{
187	void *pkt = NULL;
188	int len;
189	struct args {
190		uint32_t len;
191		char path[FNAME_SIZE];
192	} *args;
193	struct repl {
194		uint32_t errno;
195		uint32_t fhsize;
196		u_char fh[NFS_V3MAXFHSIZE];
197		uint32_t authcnt;
198		uint32_t auth[7];
199	} *repl;
200	struct {
201		uint32_t h[RPC_HEADER_WORDS];
202		struct args d;
203	} sdata;
204	size_t cc;
205
206#ifdef NFS_DEBUG
207	if (debug)
208		printf("nfs_getrootfh: %s\n", path);
209#endif
210
211	args = &sdata.d;
212
213	bzero(args, sizeof(*args));
214	len = strlen(path);
215	if (len > sizeof(args->path))
216		len = sizeof(args->path);
217	args->len = htonl(len);
218	bcopy(path, args->path, len);
219	len = sizeof(uint32_t) + roundup(len, sizeof(uint32_t));
220
221	cc = rpc_call(d, RPCPROG_MNT, RPCMNT_VER3, RPCMNT_MOUNT,
222	    args, len, (void **)&repl, &pkt);
223	if (cc == -1) {
224		free(pkt);
225		/* errno was set by rpc_call */
226		return (errno);
227	}
228	if (cc < 2 * sizeof (uint32_t)) {
229		free(pkt);
230		return (EBADRPC);
231	}
232	if (repl->errno != 0) {
233		free(pkt);
234		return (ntohl(repl->errno));
235	}
236	*fhlenp = ntohl(repl->fhsize);
237	bcopy(repl->fh, fhp, *fhlenp);
238
239	set_nfs_read_size();
240	free(pkt);
241	return (0);
242}
243
244/*
245 * Lookup a file.  Store handle and attributes.
246 * Return zero or error number.
247 */
248int
249nfs_lookupfh(struct nfs_iodesc *d, const char *name, struct nfs_iodesc *newfd)
250{
251	void *pkt = NULL;
252	int len, pos;
253	struct args {
254		uint32_t fhsize;
255		uint32_t fhplusname[1 +
256		    (NFS_V3MAXFHSIZE + FNAME_SIZE) / sizeof(uint32_t)];
257	} *args;
258	struct repl {
259		uint32_t errno;
260		uint32_t fhsize;
261		uint32_t fhplusattr[(NFS_V3MAXFHSIZE +
262		    2 * (sizeof(uint32_t) +
263		    sizeof(struct nfsv3_fattrs))) / sizeof(uint32_t)];
264	} *repl;
265	struct {
266		uint32_t h[RPC_HEADER_WORDS];
267		struct args d;
268	} sdata;
269	ssize_t cc;
270
271#ifdef NFS_DEBUG
272	if (debug)
273		printf("lookupfh: called\n");
274#endif
275
276	args = &sdata.d;
277
278	bzero(args, sizeof(*args));
279	args->fhsize = htonl(d->fhsize);
280	bcopy(d->fh, args->fhplusname, d->fhsize);
281	len = strlen(name);
282	if (len > FNAME_SIZE)
283		len = FNAME_SIZE;
284	pos = roundup(d->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
285	args->fhplusname[pos++] = htonl(len);
286	bcopy(name, &args->fhplusname[pos], len);
287	len = sizeof(uint32_t) + pos * sizeof(uint32_t) +
288	    roundup(len, sizeof(uint32_t));
289
290	cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_LOOKUP,
291	    args, len, (void **)&repl, &pkt);
292	if (cc == -1) {
293		free(pkt);
294		return (errno);		/* XXX - from rpc_call */
295	}
296	if (cc < 2 * sizeof(uint32_t)) {
297		free(pkt);
298		return (EIO);
299	}
300	if (repl->errno != 0) {
301		free(pkt);
302		/* saerrno.h now matches NFS error numbers. */
303		return (ntohl(repl->errno));
304	}
305	newfd->fhsize = ntohl(repl->fhsize);
306	bcopy(repl->fhplusattr, &newfd->fh, newfd->fhsize);
307	pos = roundup(newfd->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
308	if (repl->fhplusattr[pos++] == 0) {
309		free(pkt);
310		return (EIO);
311	}
312	bcopy(&repl->fhplusattr[pos], &newfd->fa, sizeof(newfd->fa));
313	free(pkt);
314	return (0);
315}
316
317#ifndef NFS_NOSYMLINK
318/*
319 * Get the destination of a symbolic link.
320 */
321int
322nfs_readlink(struct nfs_iodesc *d, char *buf)
323{
324	void *pkt = NULL;
325	struct args {
326		uint32_t fhsize;
327		u_char fh[NFS_V3MAXFHSIZE];
328	} *args;
329	struct repl {
330		uint32_t errno;
331		uint32_t ok;
332		struct nfsv3_fattrs fa;
333		uint32_t len;
334		u_char path[NFS_MAXPATHLEN];
335	} *repl;
336	struct {
337		uint32_t h[RPC_HEADER_WORDS];
338		struct args d;
339	} sdata;
340	ssize_t cc;
341	int rc = 0;
342
343#ifdef NFS_DEBUG
344	if (debug)
345		printf("readlink: called\n");
346#endif
347
348	args = &sdata.d;
349
350	bzero(args, sizeof(*args));
351	args->fhsize = htonl(d->fhsize);
352	bcopy(d->fh, args->fh, d->fhsize);
353	cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_READLINK,
354	    args, sizeof(uint32_t) + roundup(d->fhsize, sizeof(uint32_t)),
355	    (void **)&repl, &pkt);
356	if (cc == -1)
357		return (errno);
358
359	if (cc < 2 * sizeof(uint32_t)) {
360		rc = EIO;
361		goto done;
362	}
363
364	if (repl->errno != 0) {
365		rc = ntohl(repl->errno);
366		goto done;
367	}
368
369	if (repl->ok == 0) {
370		rc = EIO;
371		goto done;
372	}
373
374	repl->len = ntohl(repl->len);
375	if (repl->len > NFS_MAXPATHLEN) {
376		rc = ENAMETOOLONG;
377		goto done;
378	}
379
380	bcopy(repl->path, buf, repl->len);
381	buf[repl->len] = 0;
382done:
383	free(pkt);
384	return (rc);
385}
386#endif
387
388/*
389 * Read data from a file.
390 * Return transfer count or -1 (and set errno)
391 */
392ssize_t
393nfs_readdata(struct nfs_iodesc *d, off_t off, void *addr, size_t len)
394{
395	void *pkt = NULL;
396	struct args {
397		uint32_t fhsize;
398		uint32_t fhoffcnt[NFS_V3MAXFHSIZE / sizeof(uint32_t) + 3];
399	} *args;
400	struct repl {
401		uint32_t errno;
402		uint32_t ok;
403		struct nfsv3_fattrs fa;
404		uint32_t count;
405		uint32_t eof;
406		uint32_t len;
407		u_char data[NFSREAD_MAX_SIZE];
408	} *repl;
409	struct {
410		uint32_t h[RPC_HEADER_WORDS];
411		struct args d;
412	} sdata;
413	size_t cc;
414	long x;
415	int hlen, rlen, pos;
416
417	args = &sdata.d;
418
419	bzero(args, sizeof(*args));
420	args->fhsize = htonl(d->fhsize);
421	bcopy(d->fh, args->fhoffcnt, d->fhsize);
422	pos = roundup(d->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
423	args->fhoffcnt[pos++] = 0;
424	args->fhoffcnt[pos++] = htonl((uint32_t)off);
425	if (len > nfs_read_size)
426		len = nfs_read_size;
427	args->fhoffcnt[pos] = htonl((uint32_t)len);
428	hlen = offsetof(struct repl, data[0]);
429
430	cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_READ,
431	    args, 4 * sizeof(uint32_t) + roundup(d->fhsize, sizeof(uint32_t)),
432	    (void **)&repl, &pkt);
433	if (cc == -1) {
434		/* errno was already set by rpc_call */
435		return (-1);
436	}
437	if (cc < hlen) {
438		errno = EBADRPC;
439		free(pkt);
440		return (-1);
441	}
442	if (repl->errno != 0) {
443		errno = ntohl(repl->errno);
444		free(pkt);
445		return (-1);
446	}
447	rlen = cc - hlen;
448	x = ntohl(repl->count);
449	if (rlen < x) {
450		printf("nfsread: short packet, %d < %ld\n", rlen, x);
451		errno = EBADRPC;
452		free(pkt);
453		return (-1);
454	}
455	bcopy(repl->data, addr, x);
456	free(pkt);
457	return (x);
458}
459
460/*
461 * Open a file.
462 * return zero or error number
463 */
464int
465nfs_open(const char *upath, struct open_file *f)
466{
467	struct iodesc *desc;
468	struct nfs_iodesc *currfd = NULL;
469	char buf[2 * NFS_V3MAXFHSIZE + 3];
470	u_char *fh;
471	char *cp;
472	int i;
473#ifndef NFS_NOSYMLINK
474	struct nfs_iodesc *newfd = NULL;
475	char *ncp;
476	int c;
477	char namebuf[NFS_MAXPATHLEN + 1];
478	char linkbuf[NFS_MAXPATHLEN + 1];
479	int nlinks = 0;
480#endif
481	int error;
482	char *path = NULL;
483
484	if (netproto != NET_NFS)
485		return (EINVAL);
486
487#ifdef NFS_DEBUG
488 	if (debug)
489 	    printf("nfs_open: %s (rootpath=%s)\n", upath, rootpath);
490#endif
491	if (!rootpath[0]) {
492		printf("no rootpath, no nfs\n");
493		return (ENXIO);
494	}
495
496	if (f->f_dev->dv_type != DEVT_NET)
497		return (EINVAL);
498
499	if (!(desc = socktodesc(*(int *)(f->f_devdata))))
500		return (EINVAL);
501
502	/* Bind to a reserved port. */
503	desc->myport = htons(--rpc_port);
504	desc->destip = rootip;
505	if ((error = nfs_getrootfh(desc, rootpath, &nfs_root_node.fhsize,
506	    nfs_root_node.fh)))
507		return (error);
508	nfs_root_node.fa.fa_type  = htonl(NFDIR);
509	nfs_root_node.fa.fa_mode  = htonl(0755);
510	nfs_root_node.fa.fa_nlink = htonl(2);
511	nfs_root_node.iodesc = desc;
512
513	fh = &nfs_root_node.fh[0];
514	buf[0] = 'X';
515	cp = &buf[1];
516	for (i = 0; i < nfs_root_node.fhsize; i++, cp += 2)
517		sprintf(cp, "%02x", fh[i]);
518	sprintf(cp, "X");
519	setenv("boot.nfsroot.server", inet_ntoa(rootip), 1);
520	setenv("boot.nfsroot.path", rootpath, 1);
521	setenv("boot.nfsroot.nfshandle", buf, 1);
522	sprintf(buf, "%d", nfs_root_node.fhsize);
523	setenv("boot.nfsroot.nfshandlelen", buf, 1);
524
525	/* Allocate file system specific data structure */
526	currfd = malloc(sizeof(*newfd));
527	if (currfd == NULL) {
528		error = ENOMEM;
529		goto out;
530	}
531#ifndef NFS_NOSYMLINK
532	bcopy(&nfs_root_node, currfd, sizeof(*currfd));
533	newfd = NULL;
534
535	cp = path = strdup(upath);
536	if (path == NULL) {
537		error = ENOMEM;
538		goto out;
539	}
540	while (*cp) {
541		/*
542		 * Remove extra separators
543		 */
544		while (*cp == '/')
545			cp++;
546
547		if (*cp == '\0')
548			break;
549		/*
550		 * Check that current node is a directory.
551		 */
552		if (currfd->fa.fa_type != htonl(NFDIR)) {
553			error = ENOTDIR;
554			goto out;
555		}
556
557		/* allocate file system specific data structure */
558		newfd = malloc(sizeof(*newfd));
559		if (newfd == NULL) {
560			error = ENOMEM;
561			goto out;
562		}
563		newfd->iodesc = currfd->iodesc;
564
565		/*
566		 * Get next component of path name.
567		 */
568		{
569			int len = 0;
570
571			ncp = cp;
572			while ((c = *cp) != '\0' && c != '/') {
573				if (++len > NFS_MAXNAMLEN) {
574					error = ENOENT;
575					goto out;
576				}
577				cp++;
578			}
579			*cp = '\0';
580		}
581
582		/* lookup a file handle */
583		error = nfs_lookupfh(currfd, ncp, newfd);
584		*cp = c;
585		if (error)
586			goto out;
587
588		/*
589		 * Check for symbolic link
590		 */
591		if (newfd->fa.fa_type == htonl(NFLNK)) {
592			int link_len, len;
593
594			error = nfs_readlink(newfd, linkbuf);
595			if (error)
596				goto out;
597
598			link_len = strlen(linkbuf);
599			len = strlen(cp);
600
601			if (link_len + len > MAXPATHLEN
602			    || ++nlinks > MAXSYMLINKS) {
603				error = ENOENT;
604				goto out;
605			}
606
607			bcopy(cp, &namebuf[link_len], len + 1);
608			bcopy(linkbuf, namebuf, link_len);
609
610			/*
611			 * If absolute pathname, restart at root.
612			 * If relative pathname, restart at parent directory.
613			 */
614			cp = namebuf;
615			if (*cp == '/')
616				bcopy(&nfs_root_node, currfd, sizeof(*currfd));
617
618			free(newfd);
619			newfd = NULL;
620
621			continue;
622		}
623
624		free(currfd);
625		currfd = newfd;
626		newfd = NULL;
627	}
628
629	error = 0;
630
631out:
632	free(newfd);
633	free(path);
634#else
635	currfd->iodesc = desc;
636
637	error = nfs_lookupfh(&nfs_root_node, upath, currfd);
638#endif
639	if (!error) {
640		currfd->off = 0;
641		currfd->cookie = 0;
642		f->f_fsdata = (void *)currfd;
643		return (0);
644	}
645
646#ifdef NFS_DEBUG
647	if (debug)
648		printf("nfs_open: %s lookupfh failed: %s\n",
649		    path, strerror(error));
650#endif
651	free(currfd);
652
653	return (error);
654}
655
656int
657nfs_close(struct open_file *f)
658{
659	struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
660
661#ifdef NFS_DEBUG
662	if (debug)
663		printf("nfs_close: fp=0x%lx\n", (u_long)fp);
664#endif
665
666	free(fp);
667	f->f_fsdata = NULL;
668
669	return (0);
670}
671
672/*
673 * read a portion of a file
674 */
675int
676nfs_read(struct open_file *f, void *buf, size_t size, size_t *resid)
677{
678	struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
679	ssize_t cc;
680	char *addr = buf;
681
682#ifdef NFS_DEBUG
683	if (debug)
684		printf("nfs_read: size=%lu off=%d\n", (u_long)size,
685		       (int)fp->off);
686#endif
687	while ((int)size > 0) {
688		twiddle(16);
689		cc = nfs_readdata(fp, fp->off, (void *)addr, size);
690		/* XXX maybe should retry on certain errors */
691		if (cc == -1) {
692#ifdef NFS_DEBUG
693			if (debug)
694				printf("nfs_read: read: %s", strerror(errno));
695#endif
696			return (errno);	/* XXX - from nfs_readdata */
697		}
698		if (cc == 0) {
699#ifdef NFS_DEBUG
700			if (debug)
701				printf("nfs_read: hit EOF unexpectantly");
702#endif
703			goto ret;
704		}
705		fp->off += cc;
706		addr += cc;
707		size -= cc;
708	}
709ret:
710	if (resid)
711		*resid = size;
712
713	return (0);
714}
715
716off_t
717nfs_seek(struct open_file *f, off_t offset, int where)
718{
719	struct nfs_iodesc *d = (struct nfs_iodesc *)f->f_fsdata;
720	uint32_t size = ntohl(d->fa.fa_size.val[1]);
721
722	switch (where) {
723	case SEEK_SET:
724		d->off = offset;
725		break;
726	case SEEK_CUR:
727		d->off += offset;
728		break;
729	case SEEK_END:
730		d->off = size - offset;
731		break;
732	default:
733		errno = EINVAL;
734		return (-1);
735	}
736
737	return (d->off);
738}
739
740/* NFNON=0, NFREG=1, NFDIR=2, NFBLK=3, NFCHR=4, NFLNK=5, NFSOCK=6, NFFIFO=7 */
741int nfs_stat_types[9] = {
742	0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, S_IFSOCK, S_IFIFO, 0 };
743
744int
745nfs_stat(struct open_file *f, struct stat *sb)
746{
747	struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
748	uint32_t ftype, mode;
749
750	ftype = ntohl(fp->fa.fa_type);
751	mode  = ntohl(fp->fa.fa_mode);
752	mode |= nfs_stat_types[ftype & 7];
753
754	sb->st_mode  = mode;
755	sb->st_nlink = ntohl(fp->fa.fa_nlink);
756	sb->st_uid   = ntohl(fp->fa.fa_uid);
757	sb->st_gid   = ntohl(fp->fa.fa_gid);
758	sb->st_size  = ntohl(fp->fa.fa_size.val[1]);
759
760	return (0);
761}
762
763static int
764nfs_readdir(struct open_file *f, struct dirent *d)
765{
766	struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
767	struct nfsv3_readdir_repl *repl;
768	struct nfsv3_readdir_entry *rent;
769	static void *pkt = NULL;
770	static char *buf;
771	static struct nfs_iodesc *pfp = NULL;
772	static uint64_t cookie = 0;
773	size_t cc;
774	int pos, rc;
775
776	struct args {
777		uint32_t fhsize;
778		uint32_t fhpluscookie[5 + NFS_V3MAXFHSIZE];
779	} *args;
780	struct {
781		uint32_t h[RPC_HEADER_WORDS];
782		struct args d;
783	} sdata;
784
785	if (fp != pfp || fp->off != cookie) {
786		pfp = NULL;
787	refill:
788		free(pkt);
789		pkt = NULL;
790		args = &sdata.d;
791		bzero(args, sizeof(*args));
792
793		args->fhsize = htonl(fp->fhsize);
794		bcopy(fp->fh, args->fhpluscookie, fp->fhsize);
795		pos = roundup(fp->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
796		args->fhpluscookie[pos++] = htonl(fp->off >> 32);
797		args->fhpluscookie[pos++] = htonl(fp->off);
798		args->fhpluscookie[pos++] = htonl(fp->cookie >> 32);
799		args->fhpluscookie[pos++] = htonl(fp->cookie);
800		args->fhpluscookie[pos] = htonl(NFS_READDIRSIZE);
801
802		cc = rpc_call(fp->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_READDIR,
803		    args, 6 * sizeof(uint32_t) +
804		    roundup(fp->fhsize, sizeof(uint32_t)),
805		    (void **)&buf, &pkt);
806		if (cc == -1) {
807			rc = errno;
808			goto err;
809		}
810		repl = (struct nfsv3_readdir_repl *)buf;
811		if (repl->errno != 0) {
812			rc = ntohl(repl->errno);
813			goto err;
814		}
815		pfp = fp;
816		cookie = fp->off;
817		fp->cookie = ((uint64_t)ntohl(repl->cookiev0) << 32) |
818		    ntohl(repl->cookiev1);
819		buf += sizeof (struct nfsv3_readdir_repl);
820	}
821	rent = (struct nfsv3_readdir_entry *)buf;
822
823	if (rent->follows == 0) {
824		/* fid0 is actually eof */
825		if (rent->fid0 != 0) {
826			rc = ENOENT;
827			goto err;
828		}
829		goto refill;
830	}
831
832	d->d_namlen = ntohl(rent->len);
833	bcopy(rent->nameplus, d->d_name, d->d_namlen);
834	d->d_name[d->d_namlen] = '\0';
835
836	pos = roundup(d->d_namlen, sizeof(uint32_t)) / sizeof(uint32_t);
837	fp->off = cookie = ((uint64_t)ntohl(rent->nameplus[pos]) << 32) |
838	    ntohl(rent->nameplus[pos + 1]);
839	pos += 2;
840	buf = (u_char *)&rent->nameplus[pos];
841	return (0);
842
843err:
844	free(pkt);
845	pkt = NULL;
846	pfp = NULL;
847	cookie = 0;
848	return (rc);
849}
850