blob: 814afaa4458a9285fc3168c47d1df6a1f8164c12 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * NFS server file handle treatment.
3 *
4 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
5 * Portions Copyright (C) 1999 G. Allen Morris III <gam3@acm.org>
6 * Extensive rewrite by Neil Brown <neilb@cse.unsw.edu.au> Southern-Spring 1999
7 * ... and again Southern-Winter 2001 to support export_operations
8 */
9
Christoph Hellwiga5694252007-07-17 04:04:28 -070010#include <linux/exportfs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011
Andy Adamson32c1eb02007-07-17 04:04:48 -070012#include <linux/sunrpc/svcauth_gss.h>
Boaz Harrosh9a74af22009-12-03 20:30:56 +020013#include "nfsd.h"
J. Bruce Fields0a3adad2009-11-04 18:12:35 -050014#include "vfs.h"
J. Bruce Fields2e8138a2007-11-15 17:05:43 -050015#include "auth.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070016
17#define NFSDDBG_FACILITY NFSDDBG_FH
Linus Torvalds1da177e2005-04-16 15:20:36 -070018
19
Linus Torvalds1da177e2005-04-16 15:20:36 -070020/*
21 * our acceptability function.
22 * if NOSUBTREECHECK, accept anything
23 * if not, require that we can walk up to exp->ex_dentry
24 * doing some checks on the 'x' bits
25 */
26static int nfsd_acceptable(void *expv, struct dentry *dentry)
27{
28 struct svc_export *exp = expv;
29 int rv;
30 struct dentry *tdentry;
31 struct dentry *parent;
32
33 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
34 return 1;
35
36 tdentry = dget(dentry);
Jan Blunck54775492008-02-14 19:38:39 -080037 while (tdentry != exp->ex_path.dentry && !IS_ROOT(tdentry)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070038 /* make sure parents give x permission to user */
39 int err;
40 parent = dget_parent(tdentry);
Al Virof419a2e2008-07-22 00:07:17 -040041 err = inode_permission(parent->d_inode, MAY_EXEC);
Linus Torvalds1da177e2005-04-16 15:20:36 -070042 if (err < 0) {
43 dput(parent);
44 break;
45 }
46 dput(tdentry);
47 tdentry = parent;
48 }
Jan Blunck54775492008-02-14 19:38:39 -080049 if (tdentry != exp->ex_path.dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -070050 dprintk("nfsd_acceptable failed at %p %s\n", tdentry, tdentry->d_name.name);
Jan Blunck54775492008-02-14 19:38:39 -080051 rv = (tdentry == exp->ex_path.dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 dput(tdentry);
53 return rv;
54}
55
56/* Type check. The correct error return for type mismatches does not seem to be
57 * generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a
58 * comment in the NFSv3 spec says this is incorrect (implementation notes for
59 * the write call).
60 */
Al Viro83b11342006-10-19 23:28:55 -070061static inline __be32
Al Viro175a4eb2011-07-26 03:30:54 -040062nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, umode_t requested)
Linus Torvalds1da177e2005-04-16 15:20:36 -070063{
J. Bruce Fieldse10f9e12011-08-15 17:04:19 -040064 mode &= S_IFMT;
65
66 if (requested == 0) /* the caller doesn't care */
67 return nfs_ok;
68 if (mode == requested)
69 return nfs_ok;
70 /*
71 * v4 has an error more specific than err_notdir which we should
72 * return in preference to err_notdir:
73 */
74 if (rqstp->rq_vers == 4 && mode == S_IFLNK)
75 return nfserr_symlink;
76 if (requested == S_IFDIR)
77 return nfserr_notdir;
78 if (mode == S_IFDIR)
79 return nfserr_isdir;
80 return nfserr_inval;
Linus Torvalds1da177e2005-04-16 15:20:36 -070081}
82
J. Bruce Fields6fa02832007-11-12 16:05:03 -050083static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp,
84 struct svc_export *exp)
85{
J. Bruce Fields12045a6e2009-12-08 18:15:52 -050086 int flags = nfsexp_flags(rqstp, exp);
87
J. Bruce Fields6fa02832007-11-12 16:05:03 -050088 /* Check if the request originated from a secure port. */
J. Bruce Fields3d354cb2009-12-20 10:43:35 -050089 if (!rqstp->rq_secure && !(flags & NFSEXP_INSECURE_PORT)) {
Pavel Emelyanov5216a8e2008-02-21 10:57:45 +030090 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
J. Bruce Fields6fa02832007-11-12 16:05:03 -050091 dprintk(KERN_WARNING
92 "nfsd: request from insecure port %s!\n",
93 svc_print_addr(rqstp, buf, sizeof(buf)));
94 return nfserr_perm;
95 }
96
97 /* Set user creds for this exportpoint */
98 return nfserrno(nfsd_setuser(rqstp, exp));
99}
100
Steve Dickson03a816b2009-09-09 15:06:05 -0400101static inline __be32 check_pseudo_root(struct svc_rqst *rqstp,
102 struct dentry *dentry, struct svc_export *exp)
103{
104 if (!(exp->ex_flags & NFSEXP_V4ROOT))
105 return nfs_ok;
106 /*
107 * v2/v3 clients have no need for the V4ROOT export--they use
108 * the mount protocl instead; also, further V4ROOT checks may be
109 * in v4-specific code, in which case v2/v3 clients could bypass
110 * them.
111 */
112 if (!nfsd_v4client(rqstp))
113 return nfserr_stale;
114 /*
115 * We're exposing only the directories and symlinks that have to be
116 * traversed on the way to real exports:
117 */
118 if (unlikely(!S_ISDIR(dentry->d_inode->i_mode) &&
119 !S_ISLNK(dentry->d_inode->i_mode)))
120 return nfserr_stale;
121 /*
122 * A pseudoroot export gives permission to access only one
123 * single directory; the kernel has to make another upcall
124 * before granting access to anything else under it:
125 */
126 if (unlikely(dentry != exp->ex_path.dentry))
127 return nfserr_stale;
128 return nfs_ok;
129}
130
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131/*
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400132 * Use the given filehandle to look up the corresponding export and
133 * dentry. On success, the results are used to set fh_export and
134 * fh_dentry.
135 */
136static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp)
137{
138 struct knfsd_fh *fh = &fhp->fh_handle;
139 struct fid *fid = NULL, sfid;
140 struct svc_export *exp;
141 struct dentry *dentry;
142 int fileid_type;
143 int data_left = fh->fh_size/4;
144 __be32 error;
145
146 error = nfserr_stale;
147 if (rqstp->rq_vers > 2)
148 error = nfserr_badhandle;
149 if (rqstp->rq_vers == 4 && fh->fh_size == 0)
150 return nfserr_nofilehandle;
151
152 if (fh->fh_version == 1) {
153 int len;
154
155 if (--data_left < 0)
156 return error;
157 if (fh->fh_auth_type != 0)
158 return error;
159 len = key_len(fh->fh_fsid_type) / 4;
160 if (len == 0)
161 return error;
162 if (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
163 /* deprecated, convert to type 3 */
164 len = key_len(FSID_ENCODE_DEV)/4;
165 fh->fh_fsid_type = FSID_ENCODE_DEV;
166 fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1])));
167 fh->fh_fsid[1] = fh->fh_fsid[2];
168 }
169 data_left -= len;
170 if (data_left < 0)
171 return error;
172 exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_auth);
173 fid = (struct fid *)(fh->fh_auth + len);
174 } else {
175 __u32 tfh[2];
176 dev_t xdev;
177 ino_t xino;
178
179 if (fh->fh_size != NFS_FHSIZE)
180 return error;
181 /* assume old filehandle format */
182 xdev = old_decode_dev(fh->ofh_xdev);
183 xino = u32_to_ino_t(fh->ofh_xino);
184 mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
185 exp = rqst_exp_find(rqstp, FSID_DEV, tfh);
186 }
187
188 error = nfserr_stale;
189 if (PTR_ERR(exp) == -ENOENT)
190 return error;
191
192 if (IS_ERR(exp))
193 return nfserrno(PTR_ERR(exp));
194
Neil Brown496d6c32008-05-08 13:03:09 +1000195 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) {
196 /* Elevate privileges so that the lack of 'r' or 'x'
197 * permission on some parent directory will
198 * not stop exportfs_decode_fh from being able
199 * to reconnect a directory into the dentry cache.
200 * The same problem can affect "SUBTREECHECK" exports,
201 * but as nfsd_acceptable depends on correct
202 * access control settings being in effect, we cannot
203 * fix that case easily.
204 */
David Howellsd84f4f92008-11-14 10:39:23 +1100205 struct cred *new = prepare_creds();
206 if (!new)
207 return nfserrno(-ENOMEM);
208 new->cap_effective =
209 cap_raise_nfsd_set(new->cap_effective,
210 new->cap_permitted);
211 put_cred(override_creds(new));
212 put_cred(new);
Neil Brown496d6c32008-05-08 13:03:09 +1000213 } else {
214 error = nfsd_setuser_and_check_port(rqstp, exp);
215 if (error)
216 goto out;
217 }
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400218
219 /*
220 * Look up the dentry using the NFS file handle.
221 */
222 error = nfserr_stale;
223 if (rqstp->rq_vers > 2)
224 error = nfserr_badhandle;
225
226 if (fh->fh_version != 1) {
227 sfid.i32.ino = fh->ofh_ino;
228 sfid.i32.gen = fh->ofh_generation;
229 sfid.i32.parent_ino = fh->ofh_dirino;
230 fid = &sfid;
231 data_left = 3;
232 if (fh->ofh_dirino == 0)
233 fileid_type = FILEID_INO32_GEN;
234 else
235 fileid_type = FILEID_INO32_GEN_PARENT;
236 } else
237 fileid_type = fh->fh_fileid_type;
238
239 if (fileid_type == FILEID_ROOT)
240 dentry = dget(exp->ex_path.dentry);
241 else {
242 dentry = exportfs_decode_fh(exp->ex_path.mnt, fid,
243 data_left, fileid_type,
244 nfsd_acceptable, exp);
245 }
246 if (dentry == NULL)
247 goto out;
248 if (IS_ERR(dentry)) {
249 if (PTR_ERR(dentry) != -EINVAL)
250 error = nfserrno(PTR_ERR(dentry));
251 goto out;
252 }
253
254 if (S_ISDIR(dentry->d_inode->i_mode) &&
255 (dentry->d_flags & DCACHE_DISCONNECTED)) {
256 printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n",
257 dentry->d_parent->d_name.name, dentry->d_name.name);
258 }
259
260 fhp->fh_dentry = dentry;
261 fhp->fh_export = exp;
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400262 return 0;
263out:
264 exp_put(exp);
265 return error;
266}
267
J. Bruce Fieldsb3d476762008-10-20 13:01:59 -0400268/**
269 * fh_verify - filehandle lookup and access checking
270 * @rqstp: pointer to current rpc request
271 * @fhp: filehandle to be verified
272 * @type: expected type of object pointed to by filehandle
273 * @access: type of access needed to object
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 *
J. Bruce Fieldsb3d476762008-10-20 13:01:59 -0400275 * Look up a dentry from the on-the-wire filehandle, check the client's
276 * access to the export, and set the current task's credentials.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277 *
J. Bruce Fieldsb3d476762008-10-20 13:01:59 -0400278 * Regardless of success or failure of fh_verify(), fh_put() should be
279 * called on @fhp when the caller is finished with the filehandle.
280 *
281 * fh_verify() may be called multiple times on a given filehandle, for
282 * example, when processing an NFSv4 compound. The first call will look
283 * up a dentry using the on-the-wire filehandle. Subsequent calls will
284 * skip the lookup and just perform the other checks and possibly change
285 * the current task's credentials.
286 *
287 * @type specifies the type of object expected using one of the S_IF*
288 * constants defined in include/linux/stat.h. The caller may use zero
289 * to indicate that it doesn't care, or a negative integer to indicate
290 * that it expects something not of the given type.
291 *
292 * @access is formed from the NFSD_MAY_* constants defined in
293 * include/linux/nfsd/nfsd.h.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 */
Al Viro83b11342006-10-19 23:28:55 -0700295__be32
Al Viro175a4eb2011-07-26 03:30:54 -0400296fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, int access)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297{
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400298 struct svc_export *exp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 struct dentry *dentry;
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400300 __be32 error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301
302 dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp));
303
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 if (!fhp->fh_dentry) {
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400305 error = nfsd_set_fh_dentry(rqstp, fhp);
NeilBrownd1bbf142006-07-30 03:03:16 -0700306 if (error)
307 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308 }
J. Bruce Fields864f0f62009-11-25 17:42:05 -0500309 dentry = fhp->fh_dentry;
310 exp = fhp->fh_export;
311 /*
312 * We still have to do all these permission checks, even when
313 * fh_dentry is already set:
314 * - fh_verify may be called multiple times with different
315 * "access" arguments (e.g. nfsd_proc_create calls
316 * fh_verify(...,NFSD_MAY_EXEC) first, then later (in
317 * nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE).
318 * - in the NFSv4 case, the filehandle may have been filled
319 * in by fh_compose, and given a dentry, but further
320 * compound operations performed with that filehandle
321 * still need permissions checks. In the worst case, a
322 * mountpoint crossing may have changed the export
323 * options, and we may now need to use a different uid
324 * (for example, if different id-squashing options are in
325 * effect on the new filesystem).
326 */
Steve Dickson03a816b2009-09-09 15:06:05 -0400327 error = check_pseudo_root(rqstp, dentry, exp);
328 if (error)
329 goto out;
330
J. Bruce Fields864f0f62009-11-25 17:42:05 -0500331 error = nfsd_setuser_and_check_port(rqstp, exp);
332 if (error)
333 goto out;
J. Bruce Fields7fc90ec2006-06-30 01:56:14 -0700334
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type);
336 if (error)
337 goto out;
338
J. Bruce Fields04716e62008-08-07 13:00:20 -0400339 /*
340 * pseudoflavor restrictions are not enforced on NLM,
341 * which clients virtually always use auth_sys for,
342 * even while using RPCSEC_GSS for NFS.
343 */
J. Bruce Fields204f4ce2011-04-08 16:32:54 -0400344 if (access & NFSD_MAY_LOCK || access & NFSD_MAY_BYPASS_GSS)
J. Bruce Fields04716e62008-08-07 13:00:20 -0400345 goto skip_pseudoflavor_check;
346 /*
347 * Clients may expect to be able to use auth_sys during mount,
348 * even if they use gss for everything else; see section 2.3.2
349 * of rfc 2623.
350 */
351 if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT
352 && exp->ex_path.dentry == dentry)
353 goto skip_pseudoflavor_check;
Andy Adamson32c1eb02007-07-17 04:04:48 -0700354
J. Bruce Fields04716e62008-08-07 13:00:20 -0400355 error = check_nfsd_access(exp, rqstp);
356 if (error)
357 goto out;
358
359skip_pseudoflavor_check:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360 /* Finally, check access permissions. */
J. Bruce Fields0ec757d2007-07-17 04:04:48 -0700361 error = nfsd_permission(rqstp, exp, dentry, access);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363 if (error) {
NeilBrown34e9a632007-01-29 13:19:52 -0800364 dprintk("fh_verify: %s/%s permission failure, "
365 "acc=%x, error=%d\n",
366 dentry->d_parent->d_name.name,
367 dentry->d_name.name,
Al Virofc2dd2e2007-02-01 13:52:43 +0000368 access, ntohl(error));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 if (error == nfserr_stale)
372 nfsdstats.fh_stale++;
373 return error;
374}
375
376
377/*
378 * Compose a file handle for an NFS reply.
379 *
380 * Note that when first composed, the dentry may not yet have
381 * an inode. In this case a call to fh_update should be made
382 * before the fh goes out on the wire ...
383 */
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700384static void _fh_update(struct svc_fh *fhp, struct svc_export *exp,
385 struct dentry *dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386{
Jan Blunck54775492008-02-14 19:38:39 -0800387 if (dentry != exp->ex_path.dentry) {
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700388 struct fid *fid = (struct fid *)
389 (fhp->fh_handle.fh_auth + fhp->fh_handle.fh_size/4 - 1);
390 int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
391 int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700393 fhp->fh_handle.fh_fileid_type =
394 exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck);
395 fhp->fh_handle.fh_size += maxsize * 4;
396 } else {
397 fhp->fh_handle.fh_fileid_type = FILEID_ROOT;
398 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399}
400
401/*
402 * for composing old style file handles
403 */
404static inline void _fh_update_old(struct dentry *dentry,
405 struct svc_export *exp,
406 struct knfsd_fh *fh)
407{
408 fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino);
409 fh->ofh_generation = dentry->d_inode->i_generation;
410 if (S_ISDIR(dentry->d_inode->i_mode) ||
411 (exp->ex_flags & NFSEXP_NOSUBTREECHECK))
412 fh->ofh_dirino = 0;
413}
414
J. Bruce Fields8e498752009-09-02 19:31:32 -0400415static bool is_root_export(struct svc_export *exp)
416{
417 return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root;
418}
419
420static struct super_block *exp_sb(struct svc_export *exp)
421{
422 return exp->ex_path.dentry->d_inode->i_sb;
423}
424
425static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp)
426{
427 switch (fsid_type) {
428 case FSID_DEV:
429 if (!old_valid_dev(exp_sb(exp)->s_dev))
430 return 0;
431 /* FALL THROUGH */
432 case FSID_MAJOR_MINOR:
433 case FSID_ENCODE_DEV:
434 return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV;
435 case FSID_NUM:
436 return exp->ex_flags & NFSEXP_FSID;
437 case FSID_UUID8:
438 case FSID_UUID16:
439 if (!is_root_export(exp))
440 return 0;
441 /* fall through */
442 case FSID_UUID4_INUM:
443 case FSID_UUID16_INUM:
444 return exp->ex_uuid != NULL;
445 }
446 return 1;
447}
448
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400449
450static void set_version_and_fsid_type(struct svc_fh *fhp, struct svc_export *exp, struct svc_fh *ref_fh)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451{
NeilBrownb41eeef2007-05-09 02:34:57 -0700452 u8 version;
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400453 u8 fsid_type;
454retry:
NeilBrownb41eeef2007-05-09 02:34:57 -0700455 version = 1;
NeilBrown7e405362006-06-30 01:56:12 -0700456 if (ref_fh && ref_fh->fh_export == exp) {
NeilBrown982aedf2007-02-14 00:33:11 -0800457 version = ref_fh->fh_handle.fh_version;
NeilBrownb41eeef2007-05-09 02:34:57 -0700458 fsid_type = ref_fh->fh_handle.fh_fsid_type;
459
NeilBrownb41eeef2007-05-09 02:34:57 -0700460 ref_fh = NULL;
461
462 switch (version) {
463 case 0xca:
NeilBrownaf6a4e22007-02-14 00:33:12 -0800464 fsid_type = FSID_DEV;
NeilBrownb41eeef2007-05-09 02:34:57 -0700465 break;
466 case 1:
467 break;
468 default:
469 goto retry;
470 }
471
J. Bruce Fields8e498752009-09-02 19:31:32 -0400472 /*
473 * As the fsid -> filesystem mapping was guided by
474 * user-space, there is no guarantee that the filesystem
475 * actually supports that fsid type. If it doesn't we
476 * loop around again without ref_fh set.
NeilBrown982aedf2007-02-14 00:33:11 -0800477 */
J. Bruce Fields8e498752009-09-02 19:31:32 -0400478 if (!fsid_type_ok_for_exp(fsid_type, exp))
479 goto retry;
Steve Dickson30fa8c02009-01-07 16:54:30 -0500480 } else if (exp->ex_flags & NFSEXP_FSID) {
481 fsid_type = FSID_NUM;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800482 } else if (exp->ex_uuid) {
483 if (fhp->fh_maxsize >= 64) {
J. Bruce Fields8e498752009-09-02 19:31:32 -0400484 if (is_root_export(exp))
NeilBrownaf6a4e22007-02-14 00:33:12 -0800485 fsid_type = FSID_UUID16;
486 else
487 fsid_type = FSID_UUID16_INUM;
488 } else {
J. Bruce Fields8e498752009-09-02 19:31:32 -0400489 if (is_root_export(exp))
NeilBrownaf6a4e22007-02-14 00:33:12 -0800490 fsid_type = FSID_UUID8;
491 else
492 fsid_type = FSID_UUID4_INUM;
493 }
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400494 } else if (!old_valid_dev(exp_sb(exp)->s_dev))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 /* for newer device numbers, we must use a newer fsid format */
NeilBrownaf6a4e22007-02-14 00:33:12 -0800496 fsid_type = FSID_ENCODE_DEV;
NeilBrown982aedf2007-02-14 00:33:11 -0800497 else
NeilBrownaf6a4e22007-02-14 00:33:12 -0800498 fsid_type = FSID_DEV;
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400499 fhp->fh_handle.fh_version = version;
500 if (version)
501 fhp->fh_handle.fh_fsid_type = fsid_type;
502}
503
504__be32
505fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
506 struct svc_fh *ref_fh)
507{
508 /* ref_fh is a reference file handle.
509 * if it is non-null and for the same filesystem, then we should compose
510 * a filehandle which is of the same version, where possible.
511 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
512 * Then create a 32byte filehandle using nfs_fhbase_old
513 *
514 */
515
516 struct inode * inode = dentry->d_inode;
517 struct dentry *parent = dentry->d_parent;
518 __u32 *datap;
519 dev_t ex_dev = exp_sb(exp)->s_dev;
520
521 dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n",
522 MAJOR(ex_dev), MINOR(ex_dev),
523 (long) exp->ex_path.dentry->d_inode->i_ino,
524 parent->d_name.name, dentry->d_name.name,
525 (inode ? inode->i_ino : 0));
526
527 /* Choose filehandle version and fsid type based on
528 * the reference filehandle (if it is in the same export)
529 * or the export options.
530 */
531 set_version_and_fsid_type(fhp, exp, ref_fh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532
533 if (ref_fh == fhp)
534 fh_put(ref_fh);
535
536 if (fhp->fh_locked || fhp->fh_dentry) {
537 printk(KERN_ERR "fh_compose: fh %s/%s not initialized!\n",
NeilBrown982aedf2007-02-14 00:33:11 -0800538 parent->d_name.name, dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539 }
540 if (fhp->fh_maxsize < NFS_FHSIZE)
541 printk(KERN_ERR "fh_compose: called with maxsize %d! %s/%s\n",
NeilBrown982aedf2007-02-14 00:33:11 -0800542 fhp->fh_maxsize,
543 parent->d_name.name, dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544
545 fhp->fh_dentry = dget(dentry); /* our internal copy */
546 fhp->fh_export = exp;
547 cache_get(&exp->h);
548
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400549 if (fhp->fh_handle.fh_version == 0xca) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550 /* old style filehandle please */
551 memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
552 fhp->fh_handle.fh_size = NFS_FHSIZE;
553 fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
554 fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev);
555 fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
NeilBrown982aedf2007-02-14 00:33:11 -0800556 fhp->fh_handle.ofh_xino =
Jan Blunck54775492008-02-14 19:38:39 -0800557 ino_t_to_u32(exp->ex_path.dentry->d_inode->i_ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
559 if (inode)
560 _fh_update_old(dentry, exp, &fhp->fh_handle);
561 } else {
562 int len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563 fhp->fh_handle.fh_auth_type = 0;
564 datap = fhp->fh_handle.fh_auth+0;
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400565 mk_fsid(fhp->fh_handle.fh_fsid_type, datap, ex_dev,
Jan Blunck54775492008-02-14 19:38:39 -0800566 exp->ex_path.dentry->d_inode->i_ino,
NeilBrownaf6a4e22007-02-14 00:33:12 -0800567 exp->ex_fsid, exp->ex_uuid);
568
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400569 len = key_len(fhp->fh_handle.fh_fsid_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 datap += len/4;
571 fhp->fh_handle.fh_size = 4 + len;
572
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700573 if (inode)
574 _fh_update(fhp, exp, dentry);
Namjae Jeon216b6cb2012-08-29 10:10:10 -0400575 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID) {
J. Bruce Fields1be10a82009-09-04 11:59:32 -0400576 fh_put(fhp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 return nfserr_opnotsupp;
J. Bruce Fields1be10a82009-09-04 11:59:32 -0400578 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579 }
580
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 return 0;
582}
583
584/*
585 * Update file handle information after changing a dentry.
586 * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
587 */
Al Viro83b11342006-10-19 23:28:55 -0700588__be32
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589fh_update(struct svc_fh *fhp)
590{
591 struct dentry *dentry;
NeilBrown982aedf2007-02-14 00:33:11 -0800592
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 if (!fhp->fh_dentry)
594 goto out_bad;
595
596 dentry = fhp->fh_dentry;
597 if (!dentry->d_inode)
598 goto out_negative;
599 if (fhp->fh_handle.fh_version != 1) {
600 _fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
601 } else {
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700602 if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT)
NeilBrown4c9608b2006-06-30 01:56:11 -0700603 goto out;
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700604
605 _fh_update(fhp, fhp->fh_export, dentry);
Namjae Jeon216b6cb2012-08-29 10:10:10 -0400606 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 return nfserr_opnotsupp;
608 }
609out:
610 return 0;
611
612out_bad:
613 printk(KERN_ERR "fh_update: fh not verified!\n");
614 goto out;
615out_negative:
616 printk(KERN_ERR "fh_update: %s/%s still negative!\n",
617 dentry->d_parent->d_name.name, dentry->d_name.name);
618 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619}
620
621/*
622 * Release a file handle.
623 */
624void
625fh_put(struct svc_fh *fhp)
626{
627 struct dentry * dentry = fhp->fh_dentry;
628 struct svc_export * exp = fhp->fh_export;
629 if (dentry) {
630 fh_unlock(fhp);
631 fhp->fh_dentry = NULL;
632 dput(dentry);
633#ifdef CONFIG_NFSD_V3
634 fhp->fh_pre_saved = 0;
635 fhp->fh_post_saved = 0;
636#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 }
Jan Kara4a55c102012-06-12 16:20:33 +0200638 fh_drop_write(fhp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639 if (exp) {
Stanislav Kinsburskya09581f2012-03-28 19:09:22 +0400640 exp_put(exp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 fhp->fh_export = NULL;
642 }
643 return;
644}
645
646/*
647 * Shorthand for dprintk()'s
648 */
649char * SVCFH_fmt(struct svc_fh *fhp)
650{
651 struct knfsd_fh *fh = &fhp->fh_handle;
652
653 static char buf[80];
654 sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x",
655 fh->fh_size,
656 fh->fh_base.fh_pad[0],
657 fh->fh_base.fh_pad[1],
658 fh->fh_base.fh_pad[2],
659 fh->fh_base.fh_pad[3],
660 fh->fh_base.fh_pad[4],
661 fh->fh_base.fh_pad[5]);
662 return buf;
663}
NeilBrownaf6a4e22007-02-14 00:33:12 -0800664
665enum fsid_source fsid_source(struct svc_fh *fhp)
666{
667 if (fhp->fh_handle.fh_version != 1)
668 return FSIDSOURCE_DEV;
669 switch(fhp->fh_handle.fh_fsid_type) {
670 case FSID_DEV:
671 case FSID_ENCODE_DEV:
672 case FSID_MAJOR_MINOR:
J. Bruce Fields8e498752009-09-02 19:31:32 -0400673 if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV)
Neil Brownb8da0d12007-09-05 17:22:13 -0400674 return FSIDSOURCE_DEV;
675 break;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800676 case FSID_NUM:
NeilBrownaf6a4e22007-02-14 00:33:12 -0800677 if (fhp->fh_export->ex_flags & NFSEXP_FSID)
678 return FSIDSOURCE_FSID;
Neil Brownb8da0d12007-09-05 17:22:13 -0400679 break;
680 default:
681 break;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800682 }
Neil Brownb8da0d12007-09-05 17:22:13 -0400683 /* either a UUID type filehandle, or the filehandle doesn't
684 * match the export.
685 */
686 if (fhp->fh_export->ex_flags & NFSEXP_FSID)
687 return FSIDSOURCE_FSID;
688 if (fhp->fh_export->ex_uuid)
689 return FSIDSOURCE_UUID;
690 return FSIDSOURCE_DEV;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800691}