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>
21 #include <linux/sunrpc/clnt.h>
22 #include <linux/sunrpc/svc.h>
23 #include <linux/nfsd/nfsd.h>
25 #define NFSDDBG_FACILITY NFSDDBG_FH
28 static int nfsd_nr_verified
;
29 static int nfsd_nr_put
;
31 extern struct export_operations export_op_default
;
33 #define CALL(ops,fun) ((ops->fun)?(ops->fun):export_op_default.fun)
36 * our acceptability function.
37 * if NOSUBTREECHECK, accept anything
38 * if not, require that we can walk up to exp->ex_dentry
39 * doing some checks on the 'x' bits
41 static int nfsd_acceptable(void *expv
, struct dentry
*dentry
)
43 struct svc_export
*exp
= expv
;
45 struct dentry
*tdentry
;
46 struct dentry
*parent
;
48 if (exp
->ex_flags
& NFSEXP_NOSUBTREECHECK
)
51 tdentry
= dget(dentry
);
52 while (tdentry
!= exp
->ex_dentry
&& ! IS_ROOT(tdentry
)) {
53 /* make sure parents give x permission to user */
55 parent
= dget_parent(tdentry
);
56 err
= permission(parent
->d_inode
, MAY_EXEC
, NULL
);
64 if (tdentry
!= exp
->ex_dentry
)
65 dprintk("nfsd_acceptable failed at %p %s\n", tdentry
, tdentry
->d_name
.name
);
66 rv
= (tdentry
== exp
->ex_dentry
);
71 /* Type check. The correct error return for type mismatches does not seem to be
72 * generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a
73 * comment in the NFSv3 spec says this is incorrect (implementation notes for
77 nfsd_mode_check(struct svc_rqst
*rqstp
, umode_t mode
, int type
)
79 /* Type can be negative when creating hardlinks - not to a dir */
80 if (type
> 0 && (mode
& S_IFMT
) != type
) {
81 if (rqstp
->rq_vers
== 4 && (mode
& S_IFMT
) == S_IFLNK
)
82 return nfserr_symlink
;
83 else if (type
== S_IFDIR
)
85 else if ((mode
& S_IFMT
) == S_IFDIR
)
90 if (type
< 0 && (mode
& S_IFMT
) == -type
) {
91 if (rqstp
->rq_vers
== 4 && (mode
& S_IFMT
) == S_IFLNK
)
92 return nfserr_symlink
;
93 else if (type
== -S_IFDIR
)
102 * Perform sanity checks on the dentry in a client's file handle.
104 * Note that the file handle dentry may need to be freed even after
107 * This is only called at the start of an nfsproc call, so fhp points to
108 * a svc_fh which is all 0 except for the over-the-wire file handle.
111 fh_verify(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, int type
, int access
)
113 struct knfsd_fh
*fh
= &fhp
->fh_handle
;
114 struct svc_export
*exp
= NULL
;
115 struct dentry
*dentry
;
118 dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp
));
120 if (!fhp
->fh_dentry
) {
122 __u32 tfh
[3]; /* filehandle fragment for oldstyle filehandles */
124 int data_left
= fh
->fh_size
/4;
126 error
= nfserr_stale
;
127 if (rqstp
->rq_client
== NULL
)
129 if (rqstp
->rq_vers
> 2)
130 error
= nfserr_badhandle
;
131 if (rqstp
->rq_vers
== 4 && fh
->fh_size
== 0)
132 return nfserr_nofilehandle
;
134 if (fh
->fh_version
== 1) {
137 if (--data_left
<0) goto out
;
138 switch (fh
->fh_auth_type
) {
142 len
= key_len(fh
->fh_fsid_type
) / 4;
143 if (len
== 0) goto out
;
144 if (fh
->fh_fsid_type
== FSID_MAJOR_MINOR
) {
145 /* deprecated, convert to type 3 */
146 len
= key_len(FSID_ENCODE_DEV
)/4;
147 fh
->fh_fsid_type
= FSID_ENCODE_DEV
;
148 fh
->fh_fsid
[0] = new_encode_dev(MKDEV(ntohl(fh
->fh_fsid
[0]), ntohl(fh
->fh_fsid
[1])));
149 fh
->fh_fsid
[1] = fh
->fh_fsid
[2];
151 if ((data_left
-= len
)<0) goto out
;
152 exp
= exp_find(rqstp
->rq_client
, fh
->fh_fsid_type
, datap
, &rqstp
->rq_chandle
);
157 if (fh
->fh_size
!= NFS_FHSIZE
)
159 /* assume old filehandle format */
160 xdev
= old_decode_dev(fh
->ofh_xdev
);
161 xino
= u32_to_ino_t(fh
->ofh_xino
);
162 mk_fsid(FSID_DEV
, tfh
, xdev
, xino
, 0, NULL
);
163 exp
= exp_find(rqstp
->rq_client
, FSID_DEV
, tfh
,
167 if (IS_ERR(exp
) && (PTR_ERR(exp
) == -EAGAIN
168 || PTR_ERR(exp
) == -ETIMEDOUT
)) {
169 error
= nfserrno(PTR_ERR(exp
));
173 error
= nfserr_stale
;
174 if (!exp
|| IS_ERR(exp
))
177 /* Check if the request originated from a secure port. */
179 if (!rqstp
->rq_secure
&& EX_SECURE(exp
)) {
180 char buf
[RPC_MAX_ADDRBUFLEN
];
182 "nfsd: request from insecure port %s!\n",
183 svc_print_addr(rqstp
, buf
, sizeof(buf
)));
187 /* Set user creds for this exportpoint */
188 error
= nfserrno(nfsd_setuser(rqstp
, exp
));
193 * Look up the dentry using the NFS file handle.
195 error
= nfserr_stale
;
196 if (rqstp
->rq_vers
> 2)
197 error
= nfserr_badhandle
;
199 if (fh
->fh_version
!= 1) {
200 tfh
[0] = fh
->ofh_ino
;
201 tfh
[1] = fh
->ofh_generation
;
202 tfh
[2] = fh
->ofh_dirino
;
205 if (fh
->ofh_dirino
== 0)
210 fileid_type
= fh
->fh_fileid_type
;
212 if (fileid_type
== 0)
213 dentry
= dget(exp
->ex_dentry
);
215 struct export_operations
*nop
= exp
->ex_mnt
->mnt_sb
->s_export_op
;
216 dentry
= CALL(nop
,decode_fh
)(exp
->ex_mnt
->mnt_sb
,
219 nfsd_acceptable
, exp
);
223 if (IS_ERR(dentry
)) {
224 if (PTR_ERR(dentry
) != -EINVAL
)
225 error
= nfserrno(PTR_ERR(dentry
));
229 if (S_ISDIR(dentry
->d_inode
->i_mode
) &&
230 (dentry
->d_flags
& DCACHE_DISCONNECTED
)) {
231 printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n",
232 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
235 fhp
->fh_dentry
= dentry
;
236 fhp
->fh_export
= exp
;
239 /* just rechecking permissions
240 * (e.g. nfsproc_create calls fh_verify, then nfsd_create does as well)
242 dprintk("nfsd: fh_verify - just checking\n");
243 dentry
= fhp
->fh_dentry
;
244 exp
= fhp
->fh_export
;
245 /* Set user creds for this exportpoint; necessary even
246 * in the "just checking" case because this may be a
247 * filehandle that was created by fh_compose, and that
248 * is about to be used in another nfsv4 compound
250 error
= nfserrno(nfsd_setuser(rqstp
, exp
));
257 error
= nfsd_mode_check(rqstp
, dentry
->d_inode
->i_mode
, type
);
261 /* Finally, check access permissions. */
262 error
= nfsd_permission(exp
, dentry
, access
);
265 dprintk("fh_verify: %s/%s permission failure, "
266 "acc=%x, error=%d\n",
267 dentry
->d_parent
->d_name
.name
,
269 access
, ntohl(error
));
272 if (exp
&& !IS_ERR(exp
))
274 if (error
== nfserr_stale
)
275 nfsdstats
.fh_stale
++;
281 * Compose a file handle for an NFS reply.
283 * Note that when first composed, the dentry may not yet have
284 * an inode. In this case a call to fh_update should be made
285 * before the fh goes out on the wire ...
287 static inline int _fh_update(struct dentry
*dentry
, struct svc_export
*exp
,
288 __u32
*datap
, int *maxsize
)
290 struct export_operations
*nop
= exp
->ex_mnt
->mnt_sb
->s_export_op
;
292 if (dentry
== exp
->ex_dentry
) {
297 return CALL(nop
,encode_fh
)(dentry
, datap
, maxsize
,
298 !(exp
->ex_flags
&NFSEXP_NOSUBTREECHECK
));
302 * for composing old style file handles
304 static inline void _fh_update_old(struct dentry
*dentry
,
305 struct svc_export
*exp
,
308 fh
->ofh_ino
= ino_t_to_u32(dentry
->d_inode
->i_ino
);
309 fh
->ofh_generation
= dentry
->d_inode
->i_generation
;
310 if (S_ISDIR(dentry
->d_inode
->i_mode
) ||
311 (exp
->ex_flags
& NFSEXP_NOSUBTREECHECK
))
316 fh_compose(struct svc_fh
*fhp
, struct svc_export
*exp
, struct dentry
*dentry
,
317 struct svc_fh
*ref_fh
)
319 /* ref_fh is a reference file handle.
320 * if it is non-null and for the same filesystem, then we should compose
321 * a filehandle which is of the same version, where possible.
322 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
323 * Then create a 32byte filehandle using nfs_fhbase_old
329 struct inode
* inode
= dentry
->d_inode
;
330 struct dentry
*parent
= dentry
->d_parent
;
332 dev_t ex_dev
= exp
->ex_dentry
->d_inode
->i_sb
->s_dev
;
333 int root_export
= (exp
->ex_dentry
== exp
->ex_dentry
->d_sb
->s_root
);
335 dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n",
336 MAJOR(ex_dev
), MINOR(ex_dev
),
337 (long) exp
->ex_dentry
->d_inode
->i_ino
,
338 parent
->d_name
.name
, dentry
->d_name
.name
,
339 (inode
? inode
->i_ino
: 0));
341 /* Choose filehandle version and fsid type based on
342 * the reference filehandle (if it is in the same export)
343 * or the export options.
345 if (ref_fh
&& ref_fh
->fh_export
== exp
) {
346 version
= ref_fh
->fh_handle
.fh_version
;
348 fsid_type
= FSID_DEV
;
350 fsid_type
= ref_fh
->fh_handle
.fh_fsid_type
;
351 /* We know this version/type works for this export
352 * so there is no need for further checks.
354 } else if (exp
->ex_uuid
) {
355 if (fhp
->fh_maxsize
>= 64) {
357 fsid_type
= FSID_UUID16
;
359 fsid_type
= FSID_UUID16_INUM
;
362 fsid_type
= FSID_UUID8
;
364 fsid_type
= FSID_UUID4_INUM
;
366 } else if (exp
->ex_flags
& NFSEXP_FSID
)
367 fsid_type
= FSID_NUM
;
368 else if (!old_valid_dev(ex_dev
))
369 /* for newer device numbers, we must use a newer fsid format */
370 fsid_type
= FSID_ENCODE_DEV
;
372 fsid_type
= FSID_DEV
;
377 if (fhp
->fh_locked
|| fhp
->fh_dentry
) {
378 printk(KERN_ERR
"fh_compose: fh %s/%s not initialized!\n",
379 parent
->d_name
.name
, dentry
->d_name
.name
);
381 if (fhp
->fh_maxsize
< NFS_FHSIZE
)
382 printk(KERN_ERR
"fh_compose: called with maxsize %d! %s/%s\n",
384 parent
->d_name
.name
, dentry
->d_name
.name
);
386 fhp
->fh_dentry
= dget(dentry
); /* our internal copy */
387 fhp
->fh_export
= exp
;
390 if (version
== 0xca) {
391 /* old style filehandle please */
392 memset(&fhp
->fh_handle
.fh_base
, 0, NFS_FHSIZE
);
393 fhp
->fh_handle
.fh_size
= NFS_FHSIZE
;
394 fhp
->fh_handle
.ofh_dcookie
= 0xfeebbaca;
395 fhp
->fh_handle
.ofh_dev
= old_encode_dev(ex_dev
);
396 fhp
->fh_handle
.ofh_xdev
= fhp
->fh_handle
.ofh_dev
;
397 fhp
->fh_handle
.ofh_xino
=
398 ino_t_to_u32(exp
->ex_dentry
->d_inode
->i_ino
);
399 fhp
->fh_handle
.ofh_dirino
= ino_t_to_u32(parent_ino(dentry
));
401 _fh_update_old(dentry
, exp
, &fhp
->fh_handle
);
404 fhp
->fh_handle
.fh_version
= 1;
405 fhp
->fh_handle
.fh_auth_type
= 0;
406 datap
= fhp
->fh_handle
.fh_auth
+0;
407 fhp
->fh_handle
.fh_fsid_type
= fsid_type
;
408 mk_fsid(fsid_type
, datap
, ex_dev
,
409 exp
->ex_dentry
->d_inode
->i_ino
,
410 exp
->ex_fsid
, exp
->ex_uuid
);
412 len
= key_len(fsid_type
);
414 fhp
->fh_handle
.fh_size
= 4 + len
;
417 int size
= (fhp
->fh_maxsize
-len
-4)/4;
418 fhp
->fh_handle
.fh_fileid_type
=
419 _fh_update(dentry
, exp
, datap
, &size
);
420 fhp
->fh_handle
.fh_size
+= size
*4;
422 if (fhp
->fh_handle
.fh_fileid_type
== 255)
423 return nfserr_opnotsupp
;
431 * Update file handle information after changing a dentry.
432 * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
435 fh_update(struct svc_fh
*fhp
)
437 struct dentry
*dentry
;
443 dentry
= fhp
->fh_dentry
;
444 if (!dentry
->d_inode
)
446 if (fhp
->fh_handle
.fh_version
!= 1) {
447 _fh_update_old(dentry
, fhp
->fh_export
, &fhp
->fh_handle
);
450 if (fhp
->fh_handle
.fh_fileid_type
!= 0)
452 datap
= fhp
->fh_handle
.fh_auth
+
453 fhp
->fh_handle
.fh_size
/4 -1;
454 size
= (fhp
->fh_maxsize
- fhp
->fh_handle
.fh_size
)/4;
455 fhp
->fh_handle
.fh_fileid_type
=
456 _fh_update(dentry
, fhp
->fh_export
, datap
, &size
);
457 fhp
->fh_handle
.fh_size
+= size
*4;
458 if (fhp
->fh_handle
.fh_fileid_type
== 255)
459 return nfserr_opnotsupp
;
465 printk(KERN_ERR
"fh_update: fh not verified!\n");
468 printk(KERN_ERR
"fh_update: %s/%s still negative!\n",
469 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
474 * Release a file handle.
477 fh_put(struct svc_fh
*fhp
)
479 struct dentry
* dentry
= fhp
->fh_dentry
;
480 struct svc_export
* exp
= fhp
->fh_export
;
483 fhp
->fh_dentry
= NULL
;
485 #ifdef CONFIG_NFSD_V3
486 fhp
->fh_pre_saved
= 0;
487 fhp
->fh_post_saved
= 0;
492 cache_put(&exp
->h
, &svc_export_cache
);
493 fhp
->fh_export
= NULL
;
499 * Shorthand for dprintk()'s
501 char * SVCFH_fmt(struct svc_fh
*fhp
)
503 struct knfsd_fh
*fh
= &fhp
->fh_handle
;
506 sprintf(buf
, "%d: %08x %08x %08x %08x %08x %08x",
508 fh
->fh_base
.fh_pad
[0],
509 fh
->fh_base
.fh_pad
[1],
510 fh
->fh_base
.fh_pad
[2],
511 fh
->fh_base
.fh_pad
[3],
512 fh
->fh_base
.fh_pad
[4],
513 fh
->fh_base
.fh_pad
[5]);
517 enum fsid_source
fsid_source(struct svc_fh
*fhp
)
519 if (fhp
->fh_handle
.fh_version
!= 1)
520 return FSIDSOURCE_DEV
;
521 switch(fhp
->fh_handle
.fh_fsid_type
) {
523 case FSID_ENCODE_DEV
:
524 case FSID_MAJOR_MINOR
:
525 return FSIDSOURCE_DEV
;
527 return FSIDSOURCE_FSID
;
529 if (fhp
->fh_export
->ex_flags
& NFSEXP_FSID
)
530 return FSIDSOURCE_FSID
;
532 return FSIDSOURCE_UUID
;