1/*	$OpenBSD: nfs.c,v 1.15 2017/05/08 20:13:46 patrick Exp $	*/
2/*	$NetBSD: nfs.c,v 1.19 1996/10/13 02:29:04 christos Exp $	*/
3
4/*-
5 *  Copyright (c) 1993 John Brezak
6 *  All rights reserved.
7 *
8 *  Redistribution and use in source and binary forms, with or without
9 *  modification, are permitted provided that the following conditions
10 *  are met:
11 *  1. Redistributions of source code must retain the above copyright
12 *     notice, this list of conditions and the following disclaimer.
13 *  2. Redistributions in binary form must reproduce the above copyright
14 *     notice, this list of conditions and the following disclaimer in the
15 *     documentation and/or other materials provided with the distribution.
16 *  3. The name of the author may not be used to endorse or promote products
17 *     derived from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
21 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
22 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
23 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
27 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
28 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <sys/param.h>
33#include <sys/time.h>
34#include <sys/socket.h>
35#include <sys/stat.h>
36
37#include <netinet/in.h>
38
39#include "rpcv2.h"
40#include "nfsv2.h"
41
42#include "stand.h"
43#include "saerrno.h"
44#include "net.h"
45#include "netif.h"
46#include "nfs.h"
47#include "rpc.h"
48
49/* Define our own NFS attributes without NQNFS stuff. */
50struct nfsv2_fattrs {
51	u_int32_t	fa_type;
52	u_int32_t	fa_mode;
53	u_int32_t	fa_nlink;
54	u_int32_t	fa_uid;
55	u_int32_t	fa_gid;
56	u_int32_t	fa_size;
57	u_int32_t	fa_blocksize;
58	u_int32_t	fa_rdev;
59	u_int32_t	fa_blocks;
60	u_int32_t	fa_fsid;
61	u_int32_t	fa_fileid;
62	struct nfsv2_time fa_atime;
63	struct nfsv2_time fa_mtime;
64	struct nfsv2_time fa_ctime;
65};
66
67
68struct nfs_read_args {
69	u_char	fh[NFS_FHSIZE];
70	u_int32_t	off;
71	u_int32_t	len;
72	u_int32_t	xxx;			/* XXX what's this for? */
73};
74
75/* Data part of nfs rpc reply (also the largest thing we receive) */
76#define NFSREAD_SIZE 1024
77struct nfs_read_repl {
78	u_int32_t	errno;
79	struct	nfsv2_fattrs fa;
80	u_int32_t	count;
81	u_char	data[NFSREAD_SIZE];
82};
83
84struct nfs_readlnk_repl {
85	u_int32_t	errno;
86	u_int32_t	len;
87	char	path[NFS_MAXPATHLEN];
88};
89
90struct nfs_iodesc {
91	struct	iodesc	*iodesc;
92	off_t	off;
93	u_char	fh[NFS_FHSIZE];
94	struct nfsv2_fattrs fa;	/* all in network order */
95};
96
97struct nfs_iodesc nfs_root_node;
98
99
100/*
101 * Fetch the root file handle (call mount daemon)
102 * On error, return non-zero and set errno.
103 */
104static int
105nfs_getrootfh(struct iodesc *d, const char *path, u_char *fhp)
106{
107	int len;
108	struct args {
109		u_int32_t	len;
110		char	path[FNAME_SIZE];
111	} *args;
112	struct repl {
113		u_int32_t	errno;
114		u_char	fh[NFS_FHSIZE];
115	} *repl;
116	struct {
117		u_int32_t	h[RPC_HEADER_WORDS];
118		struct args d;
119	} sdata;
120	struct {
121		u_int32_t	h[RPC_HEADER_WORDS];
122		struct repl d;
123	} rdata;
124	ssize_t cc;
125
126#ifdef NFS_DEBUG
127	if (debug)
128		printf("nfs_getrootfh: %s\n", path);
129#endif
130
131	args = &sdata.d;
132	repl = &rdata.d;
133
134	bzero(args, sizeof(*args));
135	len = strlen(path);
136	if (len > sizeof(args->path))
137		len = sizeof(args->path);
138	args->len = htonl(len);
139	bcopy(path, args->path, len);
140	len = 4 + roundup(len, 4);
141
142	cc = rpc_call(d, RPCPROG_MNT, RPCMNT_VER1, RPCMNT_MOUNT,
143	    args, len, repl, sizeof(*repl));
144	if (cc == -1) {
145		/* errno was set by rpc_call */
146		return (-1);
147	}
148	if (cc < 4) {
149		errno = EBADRPC;
150		return (-1);
151	}
152	if (repl->errno) {
153		errno = ntohl(repl->errno);
154		return (-1);
155	}
156	bcopy(repl->fh, fhp, sizeof(repl->fh));
157	return (0);
158}
159
160/*
161 * Lookup a file.  Store handle and attributes.
162 * Return zero or error number.
163 */
164static int
165nfs_lookupfh(struct nfs_iodesc *d, char *name, struct nfs_iodesc *newfd)
166{
167	int len, rlen;
168	struct args {
169		u_char	fh[NFS_FHSIZE];
170		u_int32_t	len;
171		char	name[FNAME_SIZE];
172	} *args;
173	struct repl {
174		u_int32_t	errno;
175		u_char	fh[NFS_FHSIZE];
176		struct	nfsv2_fattrs fa;
177	} *repl;
178	struct {
179		u_int32_t	h[RPC_HEADER_WORDS];
180		struct args d;
181	} sdata;
182	struct {
183		u_int32_t	h[RPC_HEADER_WORDS];
184		struct repl d;
185	} rdata;
186	ssize_t cc;
187
188#ifdef NFS_DEBUG
189	if (debug)
190		printf("lookupfh: called\n");
191#endif
192
193	args = &sdata.d;
194	repl = &rdata.d;
195
196	bzero(args, sizeof(*args));
197	bcopy(d->fh, args->fh, sizeof(args->fh));
198	len = strlen(name);
199	if (len > sizeof(args->name))
200		len = sizeof(args->name);
201	bcopy(name, args->name, len);
202	args->len = htonl(len);
203	len = 4 + roundup(len, 4);
204	len += NFS_FHSIZE;
205
206	rlen = sizeof(*repl);
207
208	cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER2, NFSPROC_LOOKUP,
209	    args, len, repl, rlen);
210	if (cc == -1)
211		return (errno);		/* XXX - from rpc_call */
212	if (cc < 4)
213		return (EIO);
214	if (repl->errno) {
215		/* saerrno.h now matches NFS error numbers. */
216		return (ntohl(repl->errno));
217	}
218	bcopy( repl->fh, &newfd->fh, sizeof(newfd->fh));
219	bcopy(&repl->fa, &newfd->fa, sizeof(newfd->fa));
220	return (0);
221}
222
223/*
224 * Get the destination of a symbolic link.
225 */
226static int
227nfs_readlink(struct nfs_iodesc *d, char *buf)
228{
229	struct {
230		u_int32_t	h[RPC_HEADER_WORDS];
231		u_char fh[NFS_FHSIZE];
232	} sdata;
233	struct {
234		u_int32_t	h[RPC_HEADER_WORDS];
235		struct nfs_readlnk_repl d;
236	} rdata;
237	ssize_t cc;
238
239#ifdef NFS_DEBUG
240	if (debug)
241		printf("readlink: called\n");
242#endif
243
244	bcopy(d->fh, sdata.fh, NFS_FHSIZE);
245	cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER2, NFSPROC_READLINK,
246	    sdata.fh, NFS_FHSIZE,
247	    &rdata.d, sizeof(rdata.d));
248	if (cc == -1)
249		return (errno);
250
251	if (cc < 4)
252		return (EIO);
253
254	if (rdata.d.errno)
255		return (ntohl(rdata.d.errno));
256
257	rdata.d.len = ntohl(rdata.d.len);
258	if (rdata.d.len > NFS_MAXPATHLEN)
259		return (ENAMETOOLONG);
260
261	bcopy(rdata.d.path, buf, rdata.d.len);
262	buf[rdata.d.len] = 0;
263	return (0);
264}
265
266/*
267 * Read data from a file.
268 * Return transfer count or -1 (and set errno)
269 */
270static ssize_t
271nfs_readdata(struct nfs_iodesc *d, off_t off, void *addr, size_t len)
272{
273	struct nfs_read_args *args;
274	struct nfs_read_repl *repl;
275	struct {
276		u_int32_t	h[RPC_HEADER_WORDS];
277		struct nfs_read_args d;
278	} sdata;
279	struct {
280		u_int32_t	h[RPC_HEADER_WORDS];
281		struct nfs_read_repl d;
282	} rdata;
283	ssize_t cc;
284	long x;
285	int hlen, rlen;
286
287	args = &sdata.d;
288	repl = &rdata.d;
289
290	bcopy(d->fh, args->fh, NFS_FHSIZE);
291	args->off = htonl((u_int32_t)off);
292	if (len > NFSREAD_SIZE)
293		len = NFSREAD_SIZE;
294	args->len = htonl((u_int32_t)len);
295	args->xxx = htonl((u_int32_t)0);
296	hlen = sizeof(*repl) - NFSREAD_SIZE;
297
298	cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER2, NFSPROC_READ,
299	    args, sizeof(*args),
300	    repl, sizeof(*repl));
301	if (cc == -1) {
302		/* errno was already set by rpc_call */
303		return (-1);
304	}
305	if (cc < hlen) {
306		errno = EBADRPC;
307		return (-1);
308	}
309	if (repl->errno) {
310		errno = ntohl(repl->errno);
311		return (-1);
312	}
313	rlen = cc - hlen;
314	x = ntohl(repl->count);
315	if (rlen < x) {
316		printf("nfsread: short packet, %d < %ld\n", rlen, x);
317		errno = EBADRPC;
318		return(-1);
319	}
320	bcopy(repl->data, addr, x);
321	return (x);
322}
323
324/*
325 * nfs_mount - mount this nfs filesystem to a host
326 * On error, return non-zero and set errno.
327 */
328int
329nfs_mount(int sock, struct in_addr ip, const char *path)
330{
331	struct iodesc *desc;
332	struct nfsv2_fattrs *fa;
333
334	if (!(desc = socktodesc(sock))) {
335		errno = EINVAL;
336		return(-1);
337	}
338
339	/* Bind to a reserved port. */
340	desc->myport = htons(--rpc_port);
341	desc->destip = ip;
342	if (nfs_getrootfh(desc, path, nfs_root_node.fh))
343		return (-1);
344	nfs_root_node.iodesc = desc;
345	/* Fake up attributes for the root dir. */
346	fa = &nfs_root_node.fa;
347	fa->fa_type  = htonl(NFDIR);
348	fa->fa_mode  = htonl(0755);
349	fa->fa_nlink = htonl(2);
350
351#ifdef NFS_DEBUG
352	if (debug)
353		printf("nfs_mount: got fh for %s\n", path);
354#endif
355
356	return(0);
357}
358
359/*
360 * Open a file.
361 * return zero or error number
362 */
363int
364nfs_open(char *path, struct open_file *f)
365{
366	struct nfs_iodesc *newfd, *currfd;
367	char namebuf[NFS_MAXPATHLEN + 1], *cp, *ncp;
368	char linkbuf[NFS_MAXPATHLEN + 1];
369	int nlinks = 0, error = 0, c;
370
371#ifdef NFS_DEBUG
372	if (debug)
373		printf("nfs_open: %s\n", path);
374#endif
375	if (nfs_root_node.iodesc == NULL) {
376		printf("nfs_open: must mount first.\n");
377		return (ENXIO);
378	}
379
380	currfd = &nfs_root_node;
381	newfd = 0;
382
383	cp = path;
384	while (*cp) {
385		/*
386		 * Remove extra separators
387		 */
388		while (*cp == '/')
389			cp++;
390
391		if (*cp == '\0')
392			break;
393		/*
394		 * Check that current node is a directory.
395		 */
396		if (currfd->fa.fa_type != htonl(NFDIR)) {
397			error = ENOTDIR;
398			goto out;
399		}
400
401		/* allocate file system specific data structure */
402		newfd = alloc(sizeof(*newfd));
403		newfd->iodesc = currfd->iodesc;
404		newfd->off = 0;
405
406		/*
407		 * Get next component of path name.
408		 */
409		{
410			int len = 0;
411
412			ncp = cp;
413			while ((c = *cp) != '\0' && c != '/') {
414				if (++len > NFS_MAXNAMLEN) {
415					error = ENOENT;
416					goto out;
417				}
418				cp++;
419			}
420			*cp = '\0';
421		}
422
423		/* lookup a file handle */
424		error = nfs_lookupfh(currfd, ncp, newfd);
425		*cp = c;
426		if (error)
427			goto out;
428
429		/*
430		 * Check for symbolic link
431		 */
432		if (newfd->fa.fa_type == htonl(NFLNK)) {
433			int link_len, len;
434
435			error = nfs_readlink(newfd, linkbuf);
436			if (error)
437				goto out;
438
439			link_len = strlen(linkbuf);
440			len = strlen(cp);
441
442			if (link_len + len > MAXPATHLEN ||
443			    ++nlinks > MAXSYMLINKS) {
444				error = ENOENT;
445				goto out;
446			}
447
448			bcopy(cp, &namebuf[link_len], len + 1);
449			bcopy(linkbuf, namebuf, link_len);
450
451			/*
452			 * If absolute pathname, restart at root.
453			 * If relative pathname, restart at parent directory.
454			 */
455			cp = namebuf;
456			if (*cp == '/') {
457				if (currfd != &nfs_root_node)
458					free(currfd, sizeof(*currfd));
459				currfd = &nfs_root_node;
460			}
461
462			free(newfd, sizeof(*newfd));
463			newfd = 0;
464
465			continue;
466		}
467
468		if (currfd != &nfs_root_node)
469			free(currfd, sizeof(*currfd));
470		currfd = newfd;
471		newfd = 0;
472	}
473
474	error = 0;
475
476out:
477	if (!error) {
478		f->f_fsdata = (void *)currfd;
479		return (0);
480	}
481
482#ifdef NFS_DEBUG
483	if (debug)
484		printf("nfs_open: %s lookupfh failed: %s\n",
485		    path, strerror(error));
486#endif
487	if (currfd != &nfs_root_node)
488		free(currfd, sizeof(*currfd));
489	if (newfd)
490		free(newfd, sizeof(*newfd));
491
492	return (error);
493}
494
495int
496nfs_close(struct open_file *f)
497{
498	struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
499
500#ifdef NFS_DEBUG
501	if (debug)
502		printf("nfs_close: fp=%p\n", fp);
503#endif
504
505	if (fp)
506		free(fp, sizeof(struct nfs_iodesc));
507	f->f_fsdata = NULL;
508
509	return (0);
510}
511
512/*
513 * read a portion of a file
514 */
515int
516nfs_read(struct open_file *f, void *buf, size_t size, size_t *resid)
517{
518	struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
519	ssize_t cc;
520	char *addr = buf;
521
522#ifdef NFS_DEBUG
523	if (debug)
524		printf("nfs_read: size=%d off=%d\n", size, (int)fp->off);
525#endif
526	while ((int)size > 0) {
527		twiddle();
528		cc = nfs_readdata(fp, fp->off, (void *)addr, size);
529		/* XXX maybe should retry on certain errors */
530		if (cc == -1) {
531#ifdef NFS_DEBUG
532			if (debug)
533				printf("nfs_read: read: %s", strerror(errno));
534#endif
535			return (errno);	/* XXX - from nfs_readdata */
536		}
537		if (cc == 0) {
538#ifdef NFS_DEBUG
539			if (debug)
540				printf("nfs_read: hit EOF unexpectantly");
541#endif
542			goto ret;
543		}
544		fp->off += cc;
545		addr += cc;
546		size -= cc;
547	}
548ret:
549	if (resid)
550		*resid = size;
551
552	return (0);
553}
554
555/*
556 * Not implemented.
557 */
558int
559nfs_write(struct open_file *f, void *buf, size_t size, size_t *resid)
560{
561	return (EROFS);
562}
563
564off_t
565nfs_seek(struct open_file *f, off_t offset, int where)
566{
567	struct nfs_iodesc *d = (struct nfs_iodesc *)f->f_fsdata;
568	u_int32_t size = ntohl(d->fa.fa_size);
569
570	switch (where) {
571	case SEEK_SET:
572		d->off = offset;
573		break;
574	case SEEK_CUR:
575		d->off += offset;
576		break;
577	case SEEK_END:
578		d->off = size - offset;
579		break;
580	default:
581		return (-1);
582	}
583
584	return (d->off);
585}
586
587/* NFNON=0, NFREG=1, NFDIR=2, NFBLK=3, NFCHR=4, NFLNK=5 */
588const int nfs_stat_types[8] = {
589	0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 0
590};
591
592int
593nfs_stat(struct open_file *f, struct stat *sb)
594{
595	struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
596	u_int32_t ftype, mode;
597
598	ftype = ntohl(fp->fa.fa_type);
599	mode  = ntohl(fp->fa.fa_mode);
600	mode |= nfs_stat_types[ftype & 7];
601
602	sb->st_mode  = mode;
603	sb->st_nlink = ntohl(fp->fa.fa_nlink);
604	sb->st_uid   = ntohl(fp->fa.fa_uid);
605	sb->st_gid   = ntohl(fp->fa.fa_gid);
606	sb->st_size  = ntohl(fp->fa.fa_size);
607
608	return (0);
609}
610
611/*
612 * Not implemented.
613 */
614#ifndef NO_READDIR
615int
616nfs_readdir(struct open_file *f, char *name)
617{
618	return (EROFS);
619}
620#endif
621