xref: /freebsd/stand/libsa/nfs.c (revision 4543ef516683042d46f3bd3bb8a4f3f746e00499)
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/param.h>
32 #include <sys/time.h>
33 #include <sys/socket.h>
34 #include <sys/stat.h>
35 #include <string.h>
36 #include <stddef.h>
37 
38 #include <netinet/in.h>
39 #include <netinet/in_systm.h>
40 
41 #include "rpcv2.h"
42 #include "nfsv2.h"
43 
44 #include "stand.h"
45 #include "net.h"
46 #include "netif.h"
47 #include "rpc.h"
48 
49 #define NFS_DEBUGxx
50 
51 #define NFSREAD_MIN_SIZE 1024
52 #define NFSREAD_MAX_SIZE 16384
53 
54 /* NFSv3 definitions */
55 #define	NFS_V3MAXFHSIZE		64
56 #define	NFS_VER3		3
57 #define	RPCMNT_VER3		3
58 #define	NFSPROCV3_LOOKUP	3
59 #define	NFSPROCV3_READLINK	5
60 #define	NFSPROCV3_READ		6
61 #define	NFSPROCV3_READDIR	16
62 
63 typedef struct {
64 	uint32_t val[2];
65 } n_quad;
66 
67 struct nfsv3_time {
68 	uint32_t nfs_sec;
69 	uint32_t nfs_nsec;
70 };
71 
72 struct nfsv3_fattrs {
73 	uint32_t fa_type;
74 	uint32_t fa_mode;
75 	uint32_t fa_nlink;
76 	uint32_t fa_uid;
77 	uint32_t fa_gid;
78 	n_quad fa_size;
79 	n_quad fa_used;
80 	n_quad fa_rdev;
81 	n_quad fa_fsid;
82 	n_quad fa_fileid;
83 	struct nfsv3_time fa_atime;
84 	struct nfsv3_time fa_mtime;
85 	struct nfsv3_time fa_ctime;
86 };
87 
88 /*
89  * For NFSv3, the file handle is variable in size, so most fixed sized
90  * structures for arguments won't work. For most cases, a structure
91  * that starts with any fixed size section is followed by an array
92  * that covers the maximum size required.
93  */
94 struct nfsv3_readdir_repl {
95 	uint32_t errno;
96 	uint32_t ok;
97 	struct nfsv3_fattrs fa;
98 	uint32_t cookiev0;
99 	uint32_t cookiev1;
100 };
101 
102 struct nfsv3_readdir_entry {
103 	uint32_t follows;
104 	uint32_t fid0;
105 	uint32_t fid1;
106 	uint32_t len;
107 	uint32_t nameplus[0];
108 };
109 
110 struct nfs_iodesc {
111 	struct iodesc *iodesc;
112 	off_t off;
113 	uint32_t fhsize;
114 	u_char fh[NFS_V3MAXFHSIZE];
115 	struct nfsv3_fattrs fa;	/* all in network order */
116 	uint64_t cookie;
117 };
118 
119 /*
120  * XXX interactions with tftp? See nfswrapper.c for a confusing
121  *     issue.
122  */
123 int		nfs_open(const char *path, struct open_file *f);
124 static int	nfs_close(struct open_file *f);
125 static int	nfs_read(struct open_file *f, void *buf, size_t size, size_t *resid);
126 static off_t	nfs_seek(struct open_file *f, off_t offset, int where);
127 static int	nfs_stat(struct open_file *f, struct stat *sb);
128 static int	nfs_readdir(struct open_file *f, struct dirent *d);
129 
130 struct	nfs_iodesc nfs_root_node;
131 
132 struct fs_ops nfs_fsops = {
133 	.fs_name = "nfs",
134 	.fo_open = nfs_open,
135 	.fo_close = nfs_close,
136 	.fo_read = nfs_read,
137 	.fo_write = null_write,
138 	.fo_seek = nfs_seek,
139 	.fo_stat = nfs_stat,
140 	.fo_readdir = nfs_readdir,
141 };
142 
143 static int nfs_read_size = NFSREAD_MIN_SIZE;
144 
145 /*
146  * Improve boot performance over NFS
147  */
148 static void
149 set_nfs_read_size(void)
150 {
151 	char *env, *end;
152 	char buf[10];
153 
154 	if ((env = getenv("nfs.read_size")) != NULL) {
155 		errno = 0;
156 		nfs_read_size = (int)strtol(env, &end, 0);
157 		if (errno != 0 || *env == '\0' || *end != '\0') {
158 			printf("%s: bad value: \"%s\", defaulting to %d\n",
159 			    "nfs.read_size", env, NFSREAD_MIN_SIZE);
160 			nfs_read_size = NFSREAD_MIN_SIZE;
161 		}
162 	}
163 	if (nfs_read_size < NFSREAD_MIN_SIZE) {
164 		printf("%s: bad value: \"%d\", defaulting to %d\n",
165 		    "nfs.read_size", nfs_read_size, NFSREAD_MIN_SIZE);
166 		nfs_read_size = NFSREAD_MIN_SIZE;
167 	}
168 	if (nfs_read_size > NFSREAD_MAX_SIZE) {
169 		printf("%s: bad value: \"%d\", defaulting to %d\n",
170 		    "nfs.read_size", nfs_read_size, NFSREAD_MIN_SIZE);
171 		nfs_read_size = NFSREAD_MAX_SIZE;
172 	}
173 	snprintf(buf, sizeof (buf), "%d", nfs_read_size);
174 	setenv("nfs.read_size", buf, 1);
175 }
176 
177 /*
178  * Fetch the root file handle (call mount daemon)
179  * Return zero or error number.
180  */
181 int
182 nfs_getrootfh(struct iodesc *d, char *path, uint32_t *fhlenp, u_char *fhp)
183 {
184 	void *pkt = NULL;
185 	int len;
186 	struct args {
187 		uint32_t len;
188 		char path[FNAME_SIZE];
189 	} *args;
190 	struct repl {
191 		uint32_t errno;
192 		uint32_t fhsize;
193 		u_char fh[NFS_V3MAXFHSIZE];
194 		uint32_t authcnt;
195 		uint32_t auth[7];
196 	} *repl;
197 	struct {
198 		uint32_t h[RPC_HEADER_WORDS];
199 		struct args d;
200 	} sdata;
201 	size_t cc;
202 
203 #ifdef NFS_DEBUG
204 	if (debug)
205 		printf("nfs_getrootfh: %s\n", path);
206 #endif
207 
208 	args = &sdata.d;
209 
210 	bzero(args, sizeof(*args));
211 	len = strlen(path);
212 	if (len > sizeof(args->path))
213 		len = sizeof(args->path);
214 	args->len = htonl(len);
215 	bcopy(path, args->path, len);
216 	len = sizeof(uint32_t) + roundup(len, sizeof(uint32_t));
217 
218 	cc = rpc_call(d, RPCPROG_MNT, RPCMNT_VER3, RPCMNT_MOUNT,
219 	    args, len, (void **)&repl, &pkt);
220 	if (cc == -1) {
221 		free(pkt);
222 		/* errno was set by rpc_call */
223 		return (errno);
224 	}
225 	if (cc < 2 * sizeof (uint32_t)) {
226 		free(pkt);
227 		return (EBADRPC);
228 	}
229 	if (repl->errno != 0) {
230 		free(pkt);
231 		return (ntohl(repl->errno));
232 	}
233 	*fhlenp = ntohl(repl->fhsize);
234 	bcopy(repl->fh, fhp, *fhlenp);
235 
236 	set_nfs_read_size();
237 	free(pkt);
238 	return (0);
239 }
240 
241 /*
242  * Lookup a file.  Store handle and attributes.
243  * Return zero or error number.
244  */
245 int
246 nfs_lookupfh(struct nfs_iodesc *d, const char *name, struct nfs_iodesc *newfd)
247 {
248 	void *pkt = NULL;
249 	int len, pos;
250 	struct args {
251 		uint32_t fhsize;
252 		uint32_t fhplusname[1 +
253 		    (NFS_V3MAXFHSIZE + FNAME_SIZE) / sizeof(uint32_t)];
254 	} *args;
255 	struct repl {
256 		uint32_t errno;
257 		uint32_t fhsize;
258 		uint32_t fhplusattr[(NFS_V3MAXFHSIZE +
259 		    2 * (sizeof(uint32_t) +
260 		    sizeof(struct nfsv3_fattrs))) / sizeof(uint32_t)];
261 	} *repl;
262 	struct {
263 		uint32_t h[RPC_HEADER_WORDS];
264 		struct args d;
265 	} sdata;
266 	ssize_t cc;
267 
268 #ifdef NFS_DEBUG
269 	if (debug)
270 		printf("lookupfh: called\n");
271 #endif
272 
273 	args = &sdata.d;
274 
275 	bzero(args, sizeof(*args));
276 	args->fhsize = htonl(d->fhsize);
277 	bcopy(d->fh, args->fhplusname, d->fhsize);
278 	len = strlen(name);
279 	if (len > FNAME_SIZE)
280 		len = FNAME_SIZE;
281 	pos = roundup(d->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
282 	args->fhplusname[pos++] = htonl(len);
283 	bcopy(name, &args->fhplusname[pos], len);
284 	len = sizeof(uint32_t) + pos * sizeof(uint32_t) +
285 	    roundup(len, sizeof(uint32_t));
286 
287 	cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_LOOKUP,
288 	    args, len, (void **)&repl, &pkt);
289 	if (cc == -1) {
290 		free(pkt);
291 		return (errno);		/* XXX - from rpc_call */
292 	}
293 	if (cc < 2 * sizeof(uint32_t)) {
294 		free(pkt);
295 		return (EIO);
296 	}
297 	if (repl->errno != 0) {
298 		free(pkt);
299 		/* saerrno.h now matches NFS error numbers. */
300 		return (ntohl(repl->errno));
301 	}
302 	newfd->fhsize = ntohl(repl->fhsize);
303 	bcopy(repl->fhplusattr, &newfd->fh, newfd->fhsize);
304 	pos = roundup(newfd->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
305 	if (repl->fhplusattr[pos++] == 0) {
306 		free(pkt);
307 		return (EIO);
308 	}
309 	bcopy(&repl->fhplusattr[pos], &newfd->fa, sizeof(newfd->fa));
310 	free(pkt);
311 	return (0);
312 }
313 
314 #ifndef NFS_NOSYMLINK
315 /*
316  * Get the destination of a symbolic link.
317  */
318 int
319 nfs_readlink(struct nfs_iodesc *d, char *buf)
320 {
321 	void *pkt = NULL;
322 	struct args {
323 		uint32_t fhsize;
324 		u_char fh[NFS_V3MAXFHSIZE];
325 	} *args;
326 	struct repl {
327 		uint32_t errno;
328 		uint32_t ok;
329 		struct nfsv3_fattrs fa;
330 		uint32_t len;
331 		u_char path[NFS_MAXPATHLEN];
332 	} *repl;
333 	struct {
334 		uint32_t h[RPC_HEADER_WORDS];
335 		struct args d;
336 	} sdata;
337 	ssize_t cc;
338 	int rc = 0;
339 
340 #ifdef NFS_DEBUG
341 	if (debug)
342 		printf("readlink: called\n");
343 #endif
344 
345 	args = &sdata.d;
346 
347 	bzero(args, sizeof(*args));
348 	args->fhsize = htonl(d->fhsize);
349 	bcopy(d->fh, args->fh, d->fhsize);
350 	cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_READLINK,
351 	    args, sizeof(uint32_t) + roundup(d->fhsize, sizeof(uint32_t)),
352 	    (void **)&repl, &pkt);
353 	if (cc == -1)
354 		return (errno);
355 
356 	if (cc < 2 * sizeof(uint32_t)) {
357 		rc = EIO;
358 		goto done;
359 	}
360 
361 	if (repl->errno != 0) {
362 		rc = ntohl(repl->errno);
363 		goto done;
364 	}
365 
366 	if (repl->ok == 0) {
367 		rc = EIO;
368 		goto done;
369 	}
370 
371 	repl->len = ntohl(repl->len);
372 	if (repl->len > NFS_MAXPATHLEN) {
373 		rc = ENAMETOOLONG;
374 		goto done;
375 	}
376 
377 	bcopy(repl->path, buf, repl->len);
378 	buf[repl->len] = 0;
379 done:
380 	free(pkt);
381 	return (rc);
382 }
383 #endif
384 
385 /*
386  * Read data from a file.
387  * Return transfer count or -1 (and set errno)
388  */
389 ssize_t
390 nfs_readdata(struct nfs_iodesc *d, off_t off, void *addr, size_t len)
391 {
392 	void *pkt = NULL;
393 	struct args {
394 		uint32_t fhsize;
395 		uint32_t fhoffcnt[NFS_V3MAXFHSIZE / sizeof(uint32_t) + 3];
396 	} *args;
397 	struct repl {
398 		uint32_t errno;
399 		uint32_t ok;
400 		struct nfsv3_fattrs fa;
401 		uint32_t count;
402 		uint32_t eof;
403 		uint32_t len;
404 		u_char data[NFSREAD_MAX_SIZE];
405 	} *repl;
406 	struct {
407 		uint32_t h[RPC_HEADER_WORDS];
408 		struct args d;
409 	} sdata;
410 	size_t cc;
411 	long x;
412 	int hlen, rlen, pos;
413 
414 	args = &sdata.d;
415 
416 	bzero(args, sizeof(*args));
417 	args->fhsize = htonl(d->fhsize);
418 	bcopy(d->fh, args->fhoffcnt, d->fhsize);
419 	pos = roundup(d->fhsize, sizeof(uint32_t)) / sizeof(uint32_t);
420 	args->fhoffcnt[pos++] = 0;
421 	args->fhoffcnt[pos++] = htonl((uint32_t)off);
422 	if (len > nfs_read_size)
423 		len = nfs_read_size;
424 	args->fhoffcnt[pos] = htonl((uint32_t)len);
425 	hlen = offsetof(struct repl, data[0]);
426 
427 	cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER3, NFSPROCV3_READ,
428 	    args, 4 * sizeof(uint32_t) + roundup(d->fhsize, sizeof(uint32_t)),
429 	    (void **)&repl, &pkt);
430 	if (cc == -1) {
431 		/* errno was already set by rpc_call */
432 		return (-1);
433 	}
434 	if (cc < hlen) {
435 		errno = EBADRPC;
436 		free(pkt);
437 		return (-1);
438 	}
439 	if (repl->errno != 0) {
440 		errno = ntohl(repl->errno);
441 		free(pkt);
442 		return (-1);
443 	}
444 	rlen = cc - hlen;
445 	x = ntohl(repl->count);
446 	if (rlen < x) {
447 		printf("nfsread: short packet, %d < %ld\n", rlen, x);
448 		errno = EBADRPC;
449 		free(pkt);
450 		return (-1);
451 	}
452 	bcopy(repl->data, addr, x);
453 	free(pkt);
454 	return (x);
455 }
456 
457 /*
458  * Open a file.
459  * return zero or error number
460  */
461 int
462 nfs_open(const char *upath, struct open_file *f)
463 {
464 	struct devdesc *dev;
465 	struct iodesc *desc;
466 	struct nfs_iodesc *currfd = NULL;
467 	char buf[2 * NFS_V3MAXFHSIZE + 3];
468 	u_char *fh;
469 	char *cp;
470 	int i;
471 #ifndef NFS_NOSYMLINK
472 	struct nfs_iodesc *newfd = NULL;
473 	char *ncp;
474 	int c;
475 	char namebuf[NFS_MAXPATHLEN + 1];
476 	char linkbuf[NFS_MAXPATHLEN + 1];
477 	int nlinks = 0;
478 #endif
479 	int error;
480 	char *path = NULL;
481 
482 	if (netproto != NET_NFS)
483 		return (EINVAL);
484 
485 	dev = f->f_devdata;
486 #ifdef NFS_DEBUG
487  	if (debug)
488 		printf("nfs_open: %s (rootip=%s rootpath=%s)\n", upath,
489 		    inet_ntoa(rootip), 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 *)(dev->d_opendata))))
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 
631 out:
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 
656 int
657 nfs_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  */
675 int
676 nfs_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\n", 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 unexpectedly\n");
702 #endif
703 			goto ret;
704 		}
705 		fp->off += cc;
706 		addr += cc;
707 		size -= cc;
708 	}
709 ret:
710 	if (resid)
711 		*resid = size;
712 
713 	return (0);
714 }
715 
716 off_t
717 nfs_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 */
741 int nfs_stat_types[9] = {
742 	0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, S_IFSOCK, S_IFIFO, 0 };
743 
744 int
745 nfs_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 
763 static int
764 nfs_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 = (char *)&rent->nameplus[pos];
841 	return (0);
842 
843 err:
844 	free(pkt);
845 	pkt = NULL;
846 	pfp = NULL;
847 	cookie = 0;
848 	return (rc);
849 }
850