2 * linux/fs/nfsd/nfsfh.c
4 * NFS server file handle treatment.
6 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
7 * Portions Copyright (C) 1999 G. Allen Morris III <gam3@acm.org>
8 * Extensive rewrite by Neil Brown <neilb@cse.unsw.edu.au> Southern-Spring 1999
9 * ... and again Southern-Winter 2001 to support export_operations
12 #include <linux/slab.h>
13 #include <linux/smp_lock.h>
15 #include <linux/unistd.h>
16 #include <linux/string.h>
17 #include <linux/stat.h>
18 #include <linux/dcache.h>
19 #include <linux/mount.h>
20 #include <asm/pgtable.h>
22 #include <linux/sunrpc/clnt.h>
23 #include <linux/sunrpc/svc.h>
24 #include <linux/nfsd/nfsd.h>
26 #define NFSDDBG_FACILITY NFSDDBG_FH
29 static int nfsd_nr_verified
;
30 static int nfsd_nr_put
;
32 extern struct export_operations export_op_default
;
34 #define CALL(ops,fun) ((ops->fun)?(ops->fun):export_op_default.fun)
37 * our acceptability function.
38 * if NOSUBTREECHECK, accept anything
39 * if not, require that we can walk up to exp->ex_dentry
40 * doing some checks on the 'x' bits
42 static int nfsd_acceptable(void *expv
, struct dentry
*dentry
)
44 struct svc_export
*exp
= expv
;
46 struct dentry
*tdentry
;
47 struct dentry
*parent
;
49 if (exp
->ex_flags
& NFSEXP_NOSUBTREECHECK
)
52 tdentry
= dget(dentry
);
53 while (tdentry
!= exp
->ex_dentry
&& ! IS_ROOT(tdentry
)) {
54 /* make sure parents give x permission to user */
56 parent
= dget_parent(tdentry
);
57 err
= permission(parent
->d_inode
, MAY_EXEC
, NULL
);
65 if (tdentry
!= exp
->ex_dentry
)
66 dprintk("nfsd_acceptable failed at %p %s\n", tdentry
, tdentry
->d_name
.name
);
67 rv
= (tdentry
== exp
->ex_dentry
);
72 /* Type check. The correct error return for type mismatches does not seem to be
73 * generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a
74 * comment in the NFSv3 spec says this is incorrect (implementation notes for
78 nfsd_mode_check(struct svc_rqst
*rqstp
, umode_t mode
, int type
)
80 /* Type can be negative when creating hardlinks - not to a dir */
81 if (type
> 0 && (mode
& S_IFMT
) != type
) {
82 if (rqstp
->rq_vers
== 4 && (mode
& S_IFMT
) == S_IFLNK
)
83 return nfserr_symlink
;
84 else if (type
== S_IFDIR
)
86 else if ((mode
& S_IFMT
) == S_IFDIR
)
91 if (type
< 0 && (mode
& S_IFMT
) == -type
) {
92 if (rqstp
->rq_vers
== 4 && (mode
& S_IFMT
) == S_IFLNK
)
93 return nfserr_symlink
;
94 else if (type
== -S_IFDIR
)
103 * Perform sanity checks on the dentry in a client's file handle.
105 * Note that the file handle dentry may need to be freed even after
108 * This is only called at the start of an nfsproc call, so fhp points to
109 * a svc_fh which is all 0 except for the over-the-wire file handle.
112 fh_verify(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, int type
, int access
)
114 struct knfsd_fh
*fh
= &fhp
->fh_handle
;
115 struct svc_export
*exp
= NULL
;
116 struct dentry
*dentry
;
119 dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp
));
121 if (!fhp
->fh_dentry
) {
123 __u32 tfh
[3]; /* filehandle fragment for oldstyle filehandles */
125 int data_left
= fh
->fh_size
/4;
127 error
= nfserr_stale
;
128 if (rqstp
->rq_client
== NULL
)
130 if (rqstp
->rq_vers
> 2)
131 error
= nfserr_badhandle
;
132 if (rqstp
->rq_vers
== 4 && fh
->fh_size
== 0)
133 return nfserr_nofilehandle
;
135 if (fh
->fh_version
== 1) {
138 if (--data_left
<0) goto out
;
139 switch (fh
->fh_auth_type
) {
143 len
= key_len(fh
->fh_fsid_type
) / 4;
144 if (len
== 0) goto out
;
145 if (fh
->fh_fsid_type
== FSID_MAJOR_MINOR
) {
146 /* deprecated, convert to type 3 */
147 len
= key_len(FSID_ENCODE_DEV
)/4;
148 fh
->fh_fsid_type
= FSID_ENCODE_DEV
;
149 fh
->fh_fsid
[0] = new_encode_dev(MKDEV(ntohl(fh
->fh_fsid
[0]), ntohl(fh
->fh_fsid
[1])));
150 fh
->fh_fsid
[1] = fh
->fh_fsid
[2];
152 if ((data_left
-= len
)<0) goto out
;
153 exp
= exp_find(rqstp
->rq_client
, fh
->fh_fsid_type
, datap
, &rqstp
->rq_chandle
);
158 if (fh
->fh_size
!= NFS_FHSIZE
)
160 /* assume old filehandle format */
161 xdev
= old_decode_dev(fh
->ofh_xdev
);
162 xino
= u32_to_ino_t(fh
->ofh_xino
);
163 mk_fsid(FSID_DEV
, tfh
, xdev
, xino
, 0, NULL
);
164 exp
= exp_find(rqstp
->rq_client
, FSID_DEV
, tfh
,
168 if (IS_ERR(exp
) && (PTR_ERR(exp
) == -EAGAIN
169 || PTR_ERR(exp
) == -ETIMEDOUT
)) {
170 error
= nfserrno(PTR_ERR(exp
));
174 error
= nfserr_stale
;
175 if (!exp
|| IS_ERR(exp
))
178 /* Check if the request originated from a secure port. */
180 if (!rqstp
->rq_secure
&& EX_SECURE(exp
)) {
181 char buf
[RPC_MAX_ADDRBUFLEN
];
183 "nfsd: request from insecure port %s!\n",
184 svc_print_addr(rqstp
, buf
, sizeof(buf
)));
188 /* Set user creds for this exportpoint */
189 error
= nfserrno(nfsd_setuser(rqstp
, exp
));
194 * Look up the dentry using the NFS file handle.
196 error
= nfserr_stale
;
197 if (rqstp
->rq_vers
> 2)
198 error
= nfserr_badhandle
;
200 if (fh
->fh_version
!= 1) {
201 tfh
[0] = fh
->ofh_ino
;
202 tfh
[1] = fh
->ofh_generation
;
203 tfh
[2] = fh
->ofh_dirino
;
206 if (fh
->ofh_dirino
== 0)
211 fileid_type
= fh
->fh_fileid_type
;
213 if (fileid_type
== 0)
214 dentry
= dget(exp
->ex_dentry
);
216 struct export_operations
*nop
= exp
->ex_mnt
->mnt_sb
->s_export_op
;
217 dentry
= CALL(nop
,decode_fh
)(exp
->ex_mnt
->mnt_sb
,
220 nfsd_acceptable
, exp
);
224 if (IS_ERR(dentry
)) {
225 if (PTR_ERR(dentry
) != -EINVAL
)
226 error
= nfserrno(PTR_ERR(dentry
));
230 if (S_ISDIR(dentry
->d_inode
->i_mode
) &&
231 (dentry
->d_flags
& DCACHE_DISCONNECTED
)) {
232 printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n",
233 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
236 fhp
->fh_dentry
= dentry
;
237 fhp
->fh_export
= exp
;
240 /* just rechecking permissions
241 * (e.g. nfsproc_create calls fh_verify, then nfsd_create does as well)
243 dprintk("nfsd: fh_verify - just checking\n");
244 dentry
= fhp
->fh_dentry
;
245 exp
= fhp
->fh_export
;
246 /* Set user creds for this exportpoint; necessary even
247 * in the "just checking" case because this may be a
248 * filehandle that was created by fh_compose, and that
249 * is about to be used in another nfsv4 compound
251 error
= nfserrno(nfsd_setuser(rqstp
, exp
));
258 error
= nfsd_mode_check(rqstp
, dentry
->d_inode
->i_mode
, type
);
262 /* Finally, check access permissions. */
263 error
= nfsd_permission(exp
, dentry
, access
);
266 dprintk("fh_verify: %s/%s permission failure, "
267 "acc=%x, error=%d\n",
268 dentry
->d_parent
->d_name
.name
,
270 access
, ntohl(error
));
273 if (exp
&& !IS_ERR(exp
))
275 if (error
== nfserr_stale
)
276 nfsdstats
.fh_stale
++;
282 * Compose a file handle for an NFS reply.
284 * Note that when first composed, the dentry may not yet have
285 * an inode. In this case a call to fh_update should be made
286 * before the fh goes out on the wire ...
288 static inline int _fh_update(struct dentry
*dentry
, struct svc_export
*exp
,
289 __u32
*datap
, int *maxsize
)
291 struct export_operations
*nop
= exp
->ex_mnt
->mnt_sb
->s_export_op
;
293 if (dentry
== exp
->ex_dentry
) {
298 return CALL(nop
,encode_fh
)(dentry
, datap
, maxsize
,
299 !(exp
->ex_flags
&NFSEXP_NOSUBTREECHECK
));
303 * for composing old style file handles
305 static inline void _fh_update_old(struct dentry
*dentry
,
306 struct svc_export
*exp
,
309 fh
->ofh_ino
= ino_t_to_u32(dentry
->d_inode
->i_ino
);
310 fh
->ofh_generation
= dentry
->d_inode
->i_generation
;
311 if (S_ISDIR(dentry
->d_inode
->i_mode
) ||
312 (exp
->ex_flags
& NFSEXP_NOSUBTREECHECK
))
317 fh_compose(struct svc_fh
*fhp
, struct svc_export
*exp
, struct dentry
*dentry
,
318 struct svc_fh
*ref_fh
)
320 /* ref_fh is a reference file handle.
321 * if it is non-null and for the same filesystem, then we should compose
322 * a filehandle which is of the same version, where possible.
323 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
324 * Then create a 32byte filehandle using nfs_fhbase_old
330 struct inode
* inode
= dentry
->d_inode
;
331 struct dentry
*parent
= dentry
->d_parent
;
333 dev_t ex_dev
= exp
->ex_dentry
->d_inode
->i_sb
->s_dev
;
334 int root_export
= (exp
->ex_dentry
== exp
->ex_dentry
->d_sb
->s_root
);
336 dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n",
337 MAJOR(ex_dev
), MINOR(ex_dev
),
338 (long) exp
->ex_dentry
->d_inode
->i_ino
,
339 parent
->d_name
.name
, dentry
->d_name
.name
,
340 (inode
? inode
->i_ino
: 0));
342 /* Choose filehandle version and fsid type based on
343 * the reference filehandle (if it is in the same export)
344 * or the export options.
346 if (ref_fh
&& ref_fh
->fh_export
== exp
) {
347 version
= ref_fh
->fh_handle
.fh_version
;
349 fsid_type
= FSID_DEV
;
351 fsid_type
= ref_fh
->fh_handle
.fh_fsid_type
;
352 /* We know this version/type works for this export
353 * so there is no need for further checks.
355 } else if (exp
->ex_uuid
) {
356 if (fhp
->fh_maxsize
>= 64) {
358 fsid_type
= FSID_UUID16
;
360 fsid_type
= FSID_UUID16_INUM
;
363 fsid_type
= FSID_UUID8
;
365 fsid_type
= FSID_UUID4_INUM
;
367 } else if (exp
->ex_flags
& NFSEXP_FSID
)
368 fsid_type
= FSID_NUM
;
369 else if (!old_valid_dev(ex_dev
))
370 /* for newer device numbers, we must use a newer fsid format */
371 fsid_type
= FSID_ENCODE_DEV
;
373 fsid_type
= FSID_DEV
;
378 if (fhp
->fh_locked
|| fhp
->fh_dentry
) {
379 printk(KERN_ERR
"fh_compose: fh %s/%s not initialized!\n",
380 parent
->d_name
.name
, dentry
->d_name
.name
);
382 if (fhp
->fh_maxsize
< NFS_FHSIZE
)
383 printk(KERN_ERR
"fh_compose: called with maxsize %d! %s/%s\n",
385 parent
->d_name
.name
, dentry
->d_name
.name
);
387 fhp
->fh_dentry
= dget(dentry
); /* our internal copy */
388 fhp
->fh_export
= exp
;
391 if (version
== 0xca) {
392 /* old style filehandle please */
393 memset(&fhp
->fh_handle
.fh_base
, 0, NFS_FHSIZE
);
394 fhp
->fh_handle
.fh_size
= NFS_FHSIZE
;
395 fhp
->fh_handle
.ofh_dcookie
= 0xfeebbaca;
396 fhp
->fh_handle
.ofh_dev
= old_encode_dev(ex_dev
);
397 fhp
->fh_handle
.ofh_xdev
= fhp
->fh_handle
.ofh_dev
;
398 fhp
->fh_handle
.ofh_xino
=
399 ino_t_to_u32(exp
->ex_dentry
->d_inode
->i_ino
);
400 fhp
->fh_handle
.ofh_dirino
= ino_t_to_u32(parent_ino(dentry
));
402 _fh_update_old(dentry
, exp
, &fhp
->fh_handle
);
405 fhp
->fh_handle
.fh_version
= 1;
406 fhp
->fh_handle
.fh_auth_type
= 0;
407 datap
= fhp
->fh_handle
.fh_auth
+0;
408 fhp
->fh_handle
.fh_fsid_type
= fsid_type
;
409 mk_fsid(fsid_type
, datap
, ex_dev
,
410 exp
->ex_dentry
->d_inode
->i_ino
,
411 exp
->ex_fsid
, exp
->ex_uuid
);
413 len
= key_len(fsid_type
);
415 fhp
->fh_handle
.fh_size
= 4 + len
;
418 int size
= (fhp
->fh_maxsize
-len
-4)/4;
419 fhp
->fh_handle
.fh_fileid_type
=
420 _fh_update(dentry
, exp
, datap
, &size
);
421 fhp
->fh_handle
.fh_size
+= size
*4;
423 if (fhp
->fh_handle
.fh_fileid_type
== 255)
424 return nfserr_opnotsupp
;
432 * Update file handle information after changing a dentry.
433 * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
436 fh_update(struct svc_fh
*fhp
)
438 struct dentry
*dentry
;
444 dentry
= fhp
->fh_dentry
;
445 if (!dentry
->d_inode
)
447 if (fhp
->fh_handle
.fh_version
!= 1) {
448 _fh_update_old(dentry
, fhp
->fh_export
, &fhp
->fh_handle
);
451 if (fhp
->fh_handle
.fh_fileid_type
!= 0)
453 datap
= fhp
->fh_handle
.fh_auth
+
454 fhp
->fh_handle
.fh_size
/4 -1;
455 size
= (fhp
->fh_maxsize
- fhp
->fh_handle
.fh_size
)/4;
456 fhp
->fh_handle
.fh_fileid_type
=
457 _fh_update(dentry
, fhp
->fh_export
, datap
, &size
);
458 fhp
->fh_handle
.fh_size
+= size
*4;
459 if (fhp
->fh_handle
.fh_fileid_type
== 255)
460 return nfserr_opnotsupp
;
466 printk(KERN_ERR
"fh_update: fh not verified!\n");
469 printk(KERN_ERR
"fh_update: %s/%s still negative!\n",
470 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
475 * Release a file handle.
478 fh_put(struct svc_fh
*fhp
)
480 struct dentry
* dentry
= fhp
->fh_dentry
;
481 struct svc_export
* exp
= fhp
->fh_export
;
484 fhp
->fh_dentry
= NULL
;
486 #ifdef CONFIG_NFSD_V3
487 fhp
->fh_pre_saved
= 0;
488 fhp
->fh_post_saved
= 0;
493 cache_put(&exp
->h
, &svc_export_cache
);
494 fhp
->fh_export
= NULL
;
500 * Shorthand for dprintk()'s
502 char * SVCFH_fmt(struct svc_fh
*fhp
)
504 struct knfsd_fh
*fh
= &fhp
->fh_handle
;
507 sprintf(buf
, "%d: %08x %08x %08x %08x %08x %08x",
509 fh
->fh_base
.fh_pad
[0],
510 fh
->fh_base
.fh_pad
[1],
511 fh
->fh_base
.fh_pad
[2],
512 fh
->fh_base
.fh_pad
[3],
513 fh
->fh_base
.fh_pad
[4],
514 fh
->fh_base
.fh_pad
[5]);
518 enum fsid_source
fsid_source(struct svc_fh
*fhp
)
520 if (fhp
->fh_handle
.fh_version
!= 1)
521 return FSIDSOURCE_DEV
;
522 switch(fhp
->fh_handle
.fh_fsid_type
) {
524 case FSID_ENCODE_DEV
:
525 case FSID_MAJOR_MINOR
:
526 return FSIDSOURCE_DEV
;
528 return FSIDSOURCE_FSID
;
530 if (fhp
->fh_export
->ex_flags
& NFSEXP_FSID
)
531 return FSIDSOURCE_FSID
;
533 return FSIDSOURCE_UUID
;