blob: ec839341815477097f38ac6a5e81fb5738236697 [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)
Al Viro97e47fa2013-09-16 10:57:01 -040050 dprintk("nfsd_acceptable failed at %p %pd\n", tdentry, tdentry);
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]);
Kinglong Meea48fd0f2014-05-29 12:18:52 +080091 dprintk("nfsd: request from insecure port %s!\n",
92 svc_print_addr(rqstp, buf, sizeof(buf)));
J. Bruce Fields6fa02832007-11-12 16:05:03 -050093 return nfserr_perm;
94 }
95
96 /* Set user creds for this exportpoint */
97 return nfserrno(nfsd_setuser(rqstp, exp));
98}
99
Steve Dickson03a816b2009-09-09 15:06:05 -0400100static inline __be32 check_pseudo_root(struct svc_rqst *rqstp,
101 struct dentry *dentry, struct svc_export *exp)
102{
103 if (!(exp->ex_flags & NFSEXP_V4ROOT))
104 return nfs_ok;
105 /*
106 * v2/v3 clients have no need for the V4ROOT export--they use
107 * the mount protocl instead; also, further V4ROOT checks may be
108 * in v4-specific code, in which case v2/v3 clients could bypass
109 * them.
110 */
111 if (!nfsd_v4client(rqstp))
112 return nfserr_stale;
113 /*
114 * We're exposing only the directories and symlinks that have to be
115 * traversed on the way to real exports:
116 */
117 if (unlikely(!S_ISDIR(dentry->d_inode->i_mode) &&
118 !S_ISLNK(dentry->d_inode->i_mode)))
119 return nfserr_stale;
120 /*
121 * A pseudoroot export gives permission to access only one
122 * single directory; the kernel has to make another upcall
123 * before granting access to anything else under it:
124 */
125 if (unlikely(dentry != exp->ex_path.dentry))
126 return nfserr_stale;
127 return nfs_ok;
128}
129
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130/*
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400131 * Use the given filehandle to look up the corresponding export and
132 * dentry. On success, the results are used to set fh_export and
133 * fh_dentry.
134 */
135static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp)
136{
137 struct knfsd_fh *fh = &fhp->fh_handle;
138 struct fid *fid = NULL, sfid;
139 struct svc_export *exp;
140 struct dentry *dentry;
141 int fileid_type;
142 int data_left = fh->fh_size/4;
143 __be32 error;
144
145 error = nfserr_stale;
146 if (rqstp->rq_vers > 2)
147 error = nfserr_badhandle;
148 if (rqstp->rq_vers == 4 && fh->fh_size == 0)
149 return nfserr_nofilehandle;
150
151 if (fh->fh_version == 1) {
152 int len;
153
154 if (--data_left < 0)
155 return error;
156 if (fh->fh_auth_type != 0)
157 return error;
158 len = key_len(fh->fh_fsid_type) / 4;
159 if (len == 0)
160 return error;
161 if (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
162 /* deprecated, convert to type 3 */
163 len = key_len(FSID_ENCODE_DEV)/4;
164 fh->fh_fsid_type = FSID_ENCODE_DEV;
165 fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1])));
166 fh->fh_fsid[1] = fh->fh_fsid[2];
167 }
168 data_left -= len;
169 if (data_left < 0)
170 return error;
Christoph Hellwig5409e462014-05-07 13:49:44 +0200171 exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_fsid);
172 fid = (struct fid *)(fh->fh_fsid + len);
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400173 } else {
174 __u32 tfh[2];
175 dev_t xdev;
176 ino_t xino;
177
178 if (fh->fh_size != NFS_FHSIZE)
179 return error;
180 /* assume old filehandle format */
181 xdev = old_decode_dev(fh->ofh_xdev);
182 xino = u32_to_ino_t(fh->ofh_xino);
183 mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
184 exp = rqst_exp_find(rqstp, FSID_DEV, tfh);
185 }
186
187 error = nfserr_stale;
188 if (PTR_ERR(exp) == -ENOENT)
189 return error;
190
191 if (IS_ERR(exp))
192 return nfserrno(PTR_ERR(exp));
193
Neil Brown496d6c32008-05-08 13:03:09 +1000194 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) {
195 /* Elevate privileges so that the lack of 'r' or 'x'
196 * permission on some parent directory will
197 * not stop exportfs_decode_fh from being able
198 * to reconnect a directory into the dentry cache.
199 * The same problem can affect "SUBTREECHECK" exports,
200 * but as nfsd_acceptable depends on correct
201 * access control settings being in effect, we cannot
202 * fix that case easily.
203 */
David Howellsd84f4f92008-11-14 10:39:23 +1100204 struct cred *new = prepare_creds();
205 if (!new)
206 return nfserrno(-ENOMEM);
207 new->cap_effective =
208 cap_raise_nfsd_set(new->cap_effective,
209 new->cap_permitted);
210 put_cred(override_creds(new));
211 put_cred(new);
Neil Brown496d6c32008-05-08 13:03:09 +1000212 } else {
213 error = nfsd_setuser_and_check_port(rqstp, exp);
214 if (error)
215 goto out;
216 }
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400217
218 /*
219 * Look up the dentry using the NFS file handle.
220 */
221 error = nfserr_stale;
222 if (rqstp->rq_vers > 2)
223 error = nfserr_badhandle;
224
225 if (fh->fh_version != 1) {
226 sfid.i32.ino = fh->ofh_ino;
227 sfid.i32.gen = fh->ofh_generation;
228 sfid.i32.parent_ino = fh->ofh_dirino;
229 fid = &sfid;
230 data_left = 3;
231 if (fh->ofh_dirino == 0)
232 fileid_type = FILEID_INO32_GEN;
233 else
234 fileid_type = FILEID_INO32_GEN_PARENT;
235 } else
236 fileid_type = fh->fh_fileid_type;
237
238 if (fileid_type == FILEID_ROOT)
239 dentry = dget(exp->ex_path.dentry);
240 else {
241 dentry = exportfs_decode_fh(exp->ex_path.mnt, fid,
242 data_left, fileid_type,
243 nfsd_acceptable, exp);
244 }
245 if (dentry == NULL)
246 goto out;
247 if (IS_ERR(dentry)) {
248 if (PTR_ERR(dentry) != -EINVAL)
249 error = nfserrno(PTR_ERR(dentry));
250 goto out;
251 }
252
253 if (S_ISDIR(dentry->d_inode->i_mode) &&
254 (dentry->d_flags & DCACHE_DISCONNECTED)) {
Al Viro97e47fa2013-09-16 10:57:01 -0400255 printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %pd2\n",
256 dentry);
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400257 }
258
259 fhp->fh_dentry = dentry;
260 fhp->fh_export = exp;
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400261 return 0;
262out:
263 exp_put(exp);
264 return error;
265}
266
J. Bruce Fieldsb3d476762008-10-20 13:01:59 -0400267/**
268 * fh_verify - filehandle lookup and access checking
269 * @rqstp: pointer to current rpc request
270 * @fhp: filehandle to be verified
271 * @type: expected type of object pointed to by filehandle
272 * @access: type of access needed to object
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273 *
J. Bruce Fieldsb3d476762008-10-20 13:01:59 -0400274 * Look up a dentry from the on-the-wire filehandle, check the client's
275 * access to the export, and set the current task's credentials.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 *
J. Bruce Fieldsb3d476762008-10-20 13:01:59 -0400277 * Regardless of success or failure of fh_verify(), fh_put() should be
278 * called on @fhp when the caller is finished with the filehandle.
279 *
280 * fh_verify() may be called multiple times on a given filehandle, for
281 * example, when processing an NFSv4 compound. The first call will look
282 * up a dentry using the on-the-wire filehandle. Subsequent calls will
283 * skip the lookup and just perform the other checks and possibly change
284 * the current task's credentials.
285 *
286 * @type specifies the type of object expected using one of the S_IF*
287 * constants defined in include/linux/stat.h. The caller may use zero
288 * to indicate that it doesn't care, or a negative integer to indicate
289 * that it expects something not of the given type.
290 *
291 * @access is formed from the NFSD_MAY_* constants defined in
292 * include/linux/nfsd/nfsd.h.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 */
Al Viro83b11342006-10-19 23:28:55 -0700294__be32
Al Viro175a4eb2011-07-26 03:30:54 -0400295fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, int access)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296{
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400297 struct svc_export *exp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 struct dentry *dentry;
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400299 __be32 error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300
301 dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp));
302
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 if (!fhp->fh_dentry) {
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400304 error = nfsd_set_fh_dentry(rqstp, fhp);
NeilBrownd1bbf142006-07-30 03:03:16 -0700305 if (error)
306 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 }
J. Bruce Fields864f0f62009-11-25 17:42:05 -0500308 dentry = fhp->fh_dentry;
309 exp = fhp->fh_export;
310 /*
311 * We still have to do all these permission checks, even when
312 * fh_dentry is already set:
313 * - fh_verify may be called multiple times with different
314 * "access" arguments (e.g. nfsd_proc_create calls
315 * fh_verify(...,NFSD_MAY_EXEC) first, then later (in
316 * nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE).
317 * - in the NFSv4 case, the filehandle may have been filled
318 * in by fh_compose, and given a dentry, but further
319 * compound operations performed with that filehandle
320 * still need permissions checks. In the worst case, a
321 * mountpoint crossing may have changed the export
322 * options, and we may now need to use a different uid
323 * (for example, if different id-squashing options are in
324 * effect on the new filesystem).
325 */
Steve Dickson03a816b2009-09-09 15:06:05 -0400326 error = check_pseudo_root(rqstp, dentry, exp);
327 if (error)
328 goto out;
329
J. Bruce Fields864f0f62009-11-25 17:42:05 -0500330 error = nfsd_setuser_and_check_port(rqstp, exp);
331 if (error)
332 goto out;
J. Bruce Fields7fc90ec2006-06-30 01:56:14 -0700333
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type);
335 if (error)
336 goto out;
337
J. Bruce Fields04716e62008-08-07 13:00:20 -0400338 /*
339 * pseudoflavor restrictions are not enforced on NLM,
340 * which clients virtually always use auth_sys for,
341 * even while using RPCSEC_GSS for NFS.
342 */
J. Bruce Fields204f4ce2011-04-08 16:32:54 -0400343 if (access & NFSD_MAY_LOCK || access & NFSD_MAY_BYPASS_GSS)
J. Bruce Fields04716e62008-08-07 13:00:20 -0400344 goto skip_pseudoflavor_check;
345 /*
346 * Clients may expect to be able to use auth_sys during mount,
347 * even if they use gss for everything else; see section 2.3.2
348 * of rfc 2623.
349 */
350 if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT
351 && exp->ex_path.dentry == dentry)
352 goto skip_pseudoflavor_check;
Andy Adamson32c1eb02007-07-17 04:04:48 -0700353
J. Bruce Fields04716e62008-08-07 13:00:20 -0400354 error = check_nfsd_access(exp, rqstp);
355 if (error)
356 goto out;
357
358skip_pseudoflavor_check:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 /* Finally, check access permissions. */
J. Bruce Fields0ec757d2007-07-17 04:04:48 -0700360 error = nfsd_permission(rqstp, exp, dentry, access);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 if (error) {
Al Viro97e47fa2013-09-16 10:57:01 -0400363 dprintk("fh_verify: %pd2 permission failure, "
NeilBrown34e9a632007-01-29 13:19:52 -0800364 "acc=%x, error=%d\n",
Al Viro97e47fa2013-09-16 10:57:01 -0400365 dentry,
Al Virofc2dd2e2007-02-01 13:52:43 +0000366 access, ntohl(error));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 if (error == nfserr_stale)
370 nfsdstats.fh_stale++;
371 return error;
372}
373
374
375/*
376 * Compose a file handle for an NFS reply.
377 *
378 * Note that when first composed, the dentry may not yet have
379 * an inode. In this case a call to fh_update should be made
380 * before the fh goes out on the wire ...
381 */
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700382static void _fh_update(struct svc_fh *fhp, struct svc_export *exp,
383 struct dentry *dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384{
Jan Blunck54775492008-02-14 19:38:39 -0800385 if (dentry != exp->ex_path.dentry) {
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700386 struct fid *fid = (struct fid *)
Christoph Hellwig5409e462014-05-07 13:49:44 +0200387 (fhp->fh_handle.fh_fsid + fhp->fh_handle.fh_size/4 - 1);
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700388 int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
389 int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700391 fhp->fh_handle.fh_fileid_type =
392 exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck);
393 fhp->fh_handle.fh_size += maxsize * 4;
394 } else {
395 fhp->fh_handle.fh_fileid_type = FILEID_ROOT;
396 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397}
398
399/*
400 * for composing old style file handles
401 */
402static inline void _fh_update_old(struct dentry *dentry,
403 struct svc_export *exp,
404 struct knfsd_fh *fh)
405{
406 fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino);
407 fh->ofh_generation = dentry->d_inode->i_generation;
408 if (S_ISDIR(dentry->d_inode->i_mode) ||
409 (exp->ex_flags & NFSEXP_NOSUBTREECHECK))
410 fh->ofh_dirino = 0;
411}
412
J. Bruce Fields8e498752009-09-02 19:31:32 -0400413static bool is_root_export(struct svc_export *exp)
414{
415 return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root;
416}
417
418static struct super_block *exp_sb(struct svc_export *exp)
419{
420 return exp->ex_path.dentry->d_inode->i_sb;
421}
422
423static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp)
424{
425 switch (fsid_type) {
426 case FSID_DEV:
427 if (!old_valid_dev(exp_sb(exp)->s_dev))
428 return 0;
429 /* FALL THROUGH */
430 case FSID_MAJOR_MINOR:
431 case FSID_ENCODE_DEV:
432 return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV;
433 case FSID_NUM:
434 return exp->ex_flags & NFSEXP_FSID;
435 case FSID_UUID8:
436 case FSID_UUID16:
437 if (!is_root_export(exp))
438 return 0;
439 /* fall through */
440 case FSID_UUID4_INUM:
441 case FSID_UUID16_INUM:
442 return exp->ex_uuid != NULL;
443 }
444 return 1;
445}
446
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400447
448static 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 -0700449{
NeilBrownb41eeef2007-05-09 02:34:57 -0700450 u8 version;
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400451 u8 fsid_type;
452retry:
NeilBrownb41eeef2007-05-09 02:34:57 -0700453 version = 1;
NeilBrown7e405362006-06-30 01:56:12 -0700454 if (ref_fh && ref_fh->fh_export == exp) {
NeilBrown982aedf2007-02-14 00:33:11 -0800455 version = ref_fh->fh_handle.fh_version;
NeilBrownb41eeef2007-05-09 02:34:57 -0700456 fsid_type = ref_fh->fh_handle.fh_fsid_type;
457
NeilBrownb41eeef2007-05-09 02:34:57 -0700458 ref_fh = NULL;
459
460 switch (version) {
461 case 0xca:
NeilBrownaf6a4e22007-02-14 00:33:12 -0800462 fsid_type = FSID_DEV;
NeilBrownb41eeef2007-05-09 02:34:57 -0700463 break;
464 case 1:
465 break;
466 default:
467 goto retry;
468 }
469
J. Bruce Fields8e498752009-09-02 19:31:32 -0400470 /*
471 * As the fsid -> filesystem mapping was guided by
472 * user-space, there is no guarantee that the filesystem
473 * actually supports that fsid type. If it doesn't we
474 * loop around again without ref_fh set.
NeilBrown982aedf2007-02-14 00:33:11 -0800475 */
J. Bruce Fields8e498752009-09-02 19:31:32 -0400476 if (!fsid_type_ok_for_exp(fsid_type, exp))
477 goto retry;
Steve Dickson30fa8c02009-01-07 16:54:30 -0500478 } else if (exp->ex_flags & NFSEXP_FSID) {
479 fsid_type = FSID_NUM;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800480 } else if (exp->ex_uuid) {
481 if (fhp->fh_maxsize >= 64) {
J. Bruce Fields8e498752009-09-02 19:31:32 -0400482 if (is_root_export(exp))
NeilBrownaf6a4e22007-02-14 00:33:12 -0800483 fsid_type = FSID_UUID16;
484 else
485 fsid_type = FSID_UUID16_INUM;
486 } else {
J. Bruce Fields8e498752009-09-02 19:31:32 -0400487 if (is_root_export(exp))
NeilBrownaf6a4e22007-02-14 00:33:12 -0800488 fsid_type = FSID_UUID8;
489 else
490 fsid_type = FSID_UUID4_INUM;
491 }
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400492 } else if (!old_valid_dev(exp_sb(exp)->s_dev))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493 /* for newer device numbers, we must use a newer fsid format */
NeilBrownaf6a4e22007-02-14 00:33:12 -0800494 fsid_type = FSID_ENCODE_DEV;
NeilBrown982aedf2007-02-14 00:33:11 -0800495 else
NeilBrownaf6a4e22007-02-14 00:33:12 -0800496 fsid_type = FSID_DEV;
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400497 fhp->fh_handle.fh_version = version;
498 if (version)
499 fhp->fh_handle.fh_fsid_type = fsid_type;
500}
501
502__be32
503fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
504 struct svc_fh *ref_fh)
505{
506 /* ref_fh is a reference file handle.
507 * if it is non-null and for the same filesystem, then we should compose
508 * a filehandle which is of the same version, where possible.
509 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
510 * Then create a 32byte filehandle using nfs_fhbase_old
511 *
512 */
513
514 struct inode * inode = dentry->d_inode;
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400515 dev_t ex_dev = exp_sb(exp)->s_dev;
516
Al Viro97e47fa2013-09-16 10:57:01 -0400517 dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %pd2, ino=%ld)\n",
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400518 MAJOR(ex_dev), MINOR(ex_dev),
519 (long) exp->ex_path.dentry->d_inode->i_ino,
Al Viro97e47fa2013-09-16 10:57:01 -0400520 dentry,
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400521 (inode ? inode->i_ino : 0));
522
523 /* Choose filehandle version and fsid type based on
524 * the reference filehandle (if it is in the same export)
525 * or the export options.
526 */
527 set_version_and_fsid_type(fhp, exp, ref_fh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528
529 if (ref_fh == fhp)
530 fh_put(ref_fh);
531
532 if (fhp->fh_locked || fhp->fh_dentry) {
Al Viro97e47fa2013-09-16 10:57:01 -0400533 printk(KERN_ERR "fh_compose: fh %pd2 not initialized!\n",
534 dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 }
536 if (fhp->fh_maxsize < NFS_FHSIZE)
Al Viro97e47fa2013-09-16 10:57:01 -0400537 printk(KERN_ERR "fh_compose: called with maxsize %d! %pd2\n",
NeilBrown982aedf2007-02-14 00:33:11 -0800538 fhp->fh_maxsize,
Al Viro97e47fa2013-09-16 10:57:01 -0400539 dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540
541 fhp->fh_dentry = dget(dentry); /* our internal copy */
542 fhp->fh_export = exp;
543 cache_get(&exp->h);
544
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400545 if (fhp->fh_handle.fh_version == 0xca) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 /* old style filehandle please */
547 memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
548 fhp->fh_handle.fh_size = NFS_FHSIZE;
549 fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
550 fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev);
551 fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
NeilBrown982aedf2007-02-14 00:33:11 -0800552 fhp->fh_handle.ofh_xino =
Jan Blunck54775492008-02-14 19:38:39 -0800553 ino_t_to_u32(exp->ex_path.dentry->d_inode->i_ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
555 if (inode)
556 _fh_update_old(dentry, exp, &fhp->fh_handle);
557 } else {
Christoph Hellwig5409e462014-05-07 13:49:44 +0200558 fhp->fh_handle.fh_size =
559 key_len(fhp->fh_handle.fh_fsid_type) + 4;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 fhp->fh_handle.fh_auth_type = 0;
Christoph Hellwig5409e462014-05-07 13:49:44 +0200561
562 mk_fsid(fhp->fh_handle.fh_fsid_type,
563 fhp->fh_handle.fh_fsid,
564 ex_dev,
Jan Blunck54775492008-02-14 19:38:39 -0800565 exp->ex_path.dentry->d_inode->i_ino,
NeilBrownaf6a4e22007-02-14 00:33:12 -0800566 exp->ex_fsid, exp->ex_uuid);
567
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700568 if (inode)
569 _fh_update(fhp, exp, dentry);
Namjae Jeon216b6cb2012-08-29 10:10:10 -0400570 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID) {
J. Bruce Fields1be10a82009-09-04 11:59:32 -0400571 fh_put(fhp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 return nfserr_opnotsupp;
J. Bruce Fields1be10a82009-09-04 11:59:32 -0400573 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 }
575
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576 return 0;
577}
578
579/*
580 * Update file handle information after changing a dentry.
581 * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
582 */
Al Viro83b11342006-10-19 23:28:55 -0700583__be32
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584fh_update(struct svc_fh *fhp)
585{
586 struct dentry *dentry;
NeilBrown982aedf2007-02-14 00:33:11 -0800587
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 if (!fhp->fh_dentry)
589 goto out_bad;
590
591 dentry = fhp->fh_dentry;
592 if (!dentry->d_inode)
593 goto out_negative;
594 if (fhp->fh_handle.fh_version != 1) {
595 _fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
596 } else {
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700597 if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT)
J. Bruce Fields49e73722013-09-12 09:31:39 -0400598 return 0;
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700599
600 _fh_update(fhp, fhp->fh_export, dentry);
Namjae Jeon216b6cb2012-08-29 10:10:10 -0400601 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 return nfserr_opnotsupp;
603 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605out_bad:
606 printk(KERN_ERR "fh_update: fh not verified!\n");
J. Bruce Fields49e73722013-09-12 09:31:39 -0400607 return nfserr_serverfault;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608out_negative:
Al Viro97e47fa2013-09-16 10:57:01 -0400609 printk(KERN_ERR "fh_update: %pd2 still negative!\n",
610 dentry);
J. Bruce Fields49e73722013-09-12 09:31:39 -0400611 return nfserr_serverfault;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612}
613
614/*
615 * Release a file handle.
616 */
617void
618fh_put(struct svc_fh *fhp)
619{
620 struct dentry * dentry = fhp->fh_dentry;
621 struct svc_export * exp = fhp->fh_export;
622 if (dentry) {
623 fh_unlock(fhp);
624 fhp->fh_dentry = NULL;
625 dput(dentry);
626#ifdef CONFIG_NFSD_V3
627 fhp->fh_pre_saved = 0;
628 fhp->fh_post_saved = 0;
629#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 }
Jan Kara4a55c102012-06-12 16:20:33 +0200631 fh_drop_write(fhp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632 if (exp) {
Stanislav Kinsburskya09581f2012-03-28 19:09:22 +0400633 exp_put(exp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634 fhp->fh_export = NULL;
635 }
636 return;
637}
638
639/*
640 * Shorthand for dprintk()'s
641 */
642char * SVCFH_fmt(struct svc_fh *fhp)
643{
644 struct knfsd_fh *fh = &fhp->fh_handle;
645
646 static char buf[80];
647 sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x",
648 fh->fh_size,
649 fh->fh_base.fh_pad[0],
650 fh->fh_base.fh_pad[1],
651 fh->fh_base.fh_pad[2],
652 fh->fh_base.fh_pad[3],
653 fh->fh_base.fh_pad[4],
654 fh->fh_base.fh_pad[5]);
655 return buf;
656}
NeilBrownaf6a4e22007-02-14 00:33:12 -0800657
658enum fsid_source fsid_source(struct svc_fh *fhp)
659{
660 if (fhp->fh_handle.fh_version != 1)
661 return FSIDSOURCE_DEV;
662 switch(fhp->fh_handle.fh_fsid_type) {
663 case FSID_DEV:
664 case FSID_ENCODE_DEV:
665 case FSID_MAJOR_MINOR:
J. Bruce Fields8e498752009-09-02 19:31:32 -0400666 if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV)
Neil Brownb8da0d12007-09-05 17:22:13 -0400667 return FSIDSOURCE_DEV;
668 break;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800669 case FSID_NUM:
NeilBrownaf6a4e22007-02-14 00:33:12 -0800670 if (fhp->fh_export->ex_flags & NFSEXP_FSID)
671 return FSIDSOURCE_FSID;
Neil Brownb8da0d12007-09-05 17:22:13 -0400672 break;
673 default:
674 break;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800675 }
Neil Brownb8da0d12007-09-05 17:22:13 -0400676 /* either a UUID type filehandle, or the filehandle doesn't
677 * match the export.
678 */
679 if (fhp->fh_export->ex_flags & NFSEXP_FSID)
680 return FSIDSOURCE_FSID;
681 if (fhp->fh_export->ex_uuid)
682 return FSIDSOURCE_UUID;
683 return FSIDSOURCE_DEV;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800684}