blob: 965b478d50fc40a97a85243e478d9e47e3c38a51 [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. */
Jeff Layton4d152e22014-11-19 07:51:14 -050089 if (!test_bit(RQ_SECURE, &rqstp->rq_flags) && !(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;
Jeff Layton94ec9382014-06-17 07:44:14 -0400165 /*
166 * struct knfsd_fh uses host-endian fields, which are
167 * sometimes used to hold net-endian values. This
168 * confuses sparse, so we must use __force here to
169 * keep it from complaining.
170 */
171 fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl((__force __be32)fh->fh_fsid[0]),
172 ntohl((__force __be32)fh->fh_fsid[1])));
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400173 fh->fh_fsid[1] = fh->fh_fsid[2];
174 }
175 data_left -= len;
176 if (data_left < 0)
177 return error;
Christoph Hellwig5409e462014-05-07 13:49:44 +0200178 exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_fsid);
179 fid = (struct fid *)(fh->fh_fsid + len);
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400180 } else {
181 __u32 tfh[2];
182 dev_t xdev;
183 ino_t xino;
184
185 if (fh->fh_size != NFS_FHSIZE)
186 return error;
187 /* assume old filehandle format */
188 xdev = old_decode_dev(fh->ofh_xdev);
189 xino = u32_to_ino_t(fh->ofh_xino);
190 mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
191 exp = rqst_exp_find(rqstp, FSID_DEV, tfh);
192 }
193
194 error = nfserr_stale;
195 if (PTR_ERR(exp) == -ENOENT)
196 return error;
197
198 if (IS_ERR(exp))
199 return nfserrno(PTR_ERR(exp));
200
Neil Brown496d6c32008-05-08 13:03:09 +1000201 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) {
202 /* Elevate privileges so that the lack of 'r' or 'x'
203 * permission on some parent directory will
204 * not stop exportfs_decode_fh from being able
205 * to reconnect a directory into the dentry cache.
206 * The same problem can affect "SUBTREECHECK" exports,
207 * but as nfsd_acceptable depends on correct
208 * access control settings being in effect, we cannot
209 * fix that case easily.
210 */
David Howellsd84f4f92008-11-14 10:39:23 +1100211 struct cred *new = prepare_creds();
Kinglong Mee027bc412014-09-02 22:15:26 +0800212 if (!new) {
213 error = nfserrno(-ENOMEM);
214 goto out;
215 }
David Howellsd84f4f92008-11-14 10:39:23 +1100216 new->cap_effective =
217 cap_raise_nfsd_set(new->cap_effective,
218 new->cap_permitted);
219 put_cred(override_creds(new));
220 put_cred(new);
Neil Brown496d6c32008-05-08 13:03:09 +1000221 } else {
222 error = nfsd_setuser_and_check_port(rqstp, exp);
223 if (error)
224 goto out;
225 }
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400226
227 /*
228 * Look up the dentry using the NFS file handle.
229 */
230 error = nfserr_stale;
231 if (rqstp->rq_vers > 2)
232 error = nfserr_badhandle;
233
234 if (fh->fh_version != 1) {
235 sfid.i32.ino = fh->ofh_ino;
236 sfid.i32.gen = fh->ofh_generation;
237 sfid.i32.parent_ino = fh->ofh_dirino;
238 fid = &sfid;
239 data_left = 3;
240 if (fh->ofh_dirino == 0)
241 fileid_type = FILEID_INO32_GEN;
242 else
243 fileid_type = FILEID_INO32_GEN_PARENT;
244 } else
245 fileid_type = fh->fh_fileid_type;
246
247 if (fileid_type == FILEID_ROOT)
248 dentry = dget(exp->ex_path.dentry);
249 else {
250 dentry = exportfs_decode_fh(exp->ex_path.mnt, fid,
251 data_left, fileid_type,
252 nfsd_acceptable, exp);
253 }
254 if (dentry == NULL)
255 goto out;
256 if (IS_ERR(dentry)) {
257 if (PTR_ERR(dentry) != -EINVAL)
258 error = nfserrno(PTR_ERR(dentry));
259 goto out;
260 }
261
262 if (S_ISDIR(dentry->d_inode->i_mode) &&
263 (dentry->d_flags & DCACHE_DISCONNECTED)) {
Al Viro97e47fa2013-09-16 10:57:01 -0400264 printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %pd2\n",
265 dentry);
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400266 }
267
268 fhp->fh_dentry = dentry;
269 fhp->fh_export = exp;
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400270 return 0;
271out:
272 exp_put(exp);
273 return error;
274}
275
J. Bruce Fieldsb3d476762008-10-20 13:01:59 -0400276/**
277 * fh_verify - filehandle lookup and access checking
278 * @rqstp: pointer to current rpc request
279 * @fhp: filehandle to be verified
280 * @type: expected type of object pointed to by filehandle
281 * @access: type of access needed to object
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 *
J. Bruce Fieldsb3d476762008-10-20 13:01:59 -0400283 * Look up a dentry from the on-the-wire filehandle, check the client's
284 * access to the export, and set the current task's credentials.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285 *
J. Bruce Fieldsb3d476762008-10-20 13:01:59 -0400286 * Regardless of success or failure of fh_verify(), fh_put() should be
287 * called on @fhp when the caller is finished with the filehandle.
288 *
289 * fh_verify() may be called multiple times on a given filehandle, for
290 * example, when processing an NFSv4 compound. The first call will look
291 * up a dentry using the on-the-wire filehandle. Subsequent calls will
292 * skip the lookup and just perform the other checks and possibly change
293 * the current task's credentials.
294 *
295 * @type specifies the type of object expected using one of the S_IF*
296 * constants defined in include/linux/stat.h. The caller may use zero
297 * to indicate that it doesn't care, or a negative integer to indicate
298 * that it expects something not of the given type.
299 *
300 * @access is formed from the NFSD_MAY_* constants defined in
301 * include/linux/nfsd/nfsd.h.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 */
Al Viro83b11342006-10-19 23:28:55 -0700303__be32
Al Viro175a4eb2011-07-26 03:30:54 -0400304fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, int access)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305{
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400306 struct svc_export *exp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 struct dentry *dentry;
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400308 __be32 error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309
310 dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp));
311
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312 if (!fhp->fh_dentry) {
J. Bruce Fields03550fa2008-03-14 17:51:12 -0400313 error = nfsd_set_fh_dentry(rqstp, fhp);
NeilBrownd1bbf142006-07-30 03:03:16 -0700314 if (error)
315 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316 }
J. Bruce Fields864f0f62009-11-25 17:42:05 -0500317 dentry = fhp->fh_dentry;
318 exp = fhp->fh_export;
319 /*
320 * We still have to do all these permission checks, even when
321 * fh_dentry is already set:
322 * - fh_verify may be called multiple times with different
323 * "access" arguments (e.g. nfsd_proc_create calls
324 * fh_verify(...,NFSD_MAY_EXEC) first, then later (in
325 * nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE).
326 * - in the NFSv4 case, the filehandle may have been filled
327 * in by fh_compose, and given a dentry, but further
328 * compound operations performed with that filehandle
329 * still need permissions checks. In the worst case, a
330 * mountpoint crossing may have changed the export
331 * options, and we may now need to use a different uid
332 * (for example, if different id-squashing options are in
333 * effect on the new filesystem).
334 */
Steve Dickson03a816b2009-09-09 15:06:05 -0400335 error = check_pseudo_root(rqstp, dentry, exp);
336 if (error)
337 goto out;
338
J. Bruce Fields864f0f62009-11-25 17:42:05 -0500339 error = nfsd_setuser_and_check_port(rqstp, exp);
340 if (error)
341 goto out;
J. Bruce Fields7fc90ec2006-06-30 01:56:14 -0700342
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type);
344 if (error)
345 goto out;
346
J. Bruce Fields04716e62008-08-07 13:00:20 -0400347 /*
348 * pseudoflavor restrictions are not enforced on NLM,
349 * which clients virtually always use auth_sys for,
350 * even while using RPCSEC_GSS for NFS.
351 */
J. Bruce Fields204f4ce2011-04-08 16:32:54 -0400352 if (access & NFSD_MAY_LOCK || access & NFSD_MAY_BYPASS_GSS)
J. Bruce Fields04716e62008-08-07 13:00:20 -0400353 goto skip_pseudoflavor_check;
354 /*
355 * Clients may expect to be able to use auth_sys during mount,
356 * even if they use gss for everything else; see section 2.3.2
357 * of rfc 2623.
358 */
359 if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT
360 && exp->ex_path.dentry == dentry)
361 goto skip_pseudoflavor_check;
Andy Adamson32c1eb02007-07-17 04:04:48 -0700362
J. Bruce Fields04716e62008-08-07 13:00:20 -0400363 error = check_nfsd_access(exp, rqstp);
364 if (error)
365 goto out;
366
367skip_pseudoflavor_check:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 /* Finally, check access permissions. */
J. Bruce Fields0ec757d2007-07-17 04:04:48 -0700369 error = nfsd_permission(rqstp, exp, dentry, access);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 if (error) {
Al Viro97e47fa2013-09-16 10:57:01 -0400372 dprintk("fh_verify: %pd2 permission failure, "
NeilBrown34e9a632007-01-29 13:19:52 -0800373 "acc=%x, error=%d\n",
Al Viro97e47fa2013-09-16 10:57:01 -0400374 dentry,
Al Virofc2dd2e2007-02-01 13:52:43 +0000375 access, ntohl(error));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 if (error == nfserr_stale)
379 nfsdstats.fh_stale++;
380 return error;
381}
382
383
384/*
385 * Compose a file handle for an NFS reply.
386 *
387 * Note that when first composed, the dentry may not yet have
388 * an inode. In this case a call to fh_update should be made
389 * before the fh goes out on the wire ...
390 */
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700391static void _fh_update(struct svc_fh *fhp, struct svc_export *exp,
392 struct dentry *dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393{
Jan Blunck54775492008-02-14 19:38:39 -0800394 if (dentry != exp->ex_path.dentry) {
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700395 struct fid *fid = (struct fid *)
Christoph Hellwig5409e462014-05-07 13:49:44 +0200396 (fhp->fh_handle.fh_fsid + fhp->fh_handle.fh_size/4 - 1);
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700397 int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
398 int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700400 fhp->fh_handle.fh_fileid_type =
401 exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck);
402 fhp->fh_handle.fh_size += maxsize * 4;
403 } else {
404 fhp->fh_handle.fh_fileid_type = FILEID_ROOT;
405 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406}
407
408/*
409 * for composing old style file handles
410 */
411static inline void _fh_update_old(struct dentry *dentry,
412 struct svc_export *exp,
413 struct knfsd_fh *fh)
414{
415 fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino);
416 fh->ofh_generation = dentry->d_inode->i_generation;
417 if (S_ISDIR(dentry->d_inode->i_mode) ||
418 (exp->ex_flags & NFSEXP_NOSUBTREECHECK))
419 fh->ofh_dirino = 0;
420}
421
J. Bruce Fields8e498752009-09-02 19:31:32 -0400422static bool is_root_export(struct svc_export *exp)
423{
424 return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root;
425}
426
427static struct super_block *exp_sb(struct svc_export *exp)
428{
429 return exp->ex_path.dentry->d_inode->i_sb;
430}
431
432static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp)
433{
434 switch (fsid_type) {
435 case FSID_DEV:
436 if (!old_valid_dev(exp_sb(exp)->s_dev))
437 return 0;
438 /* FALL THROUGH */
439 case FSID_MAJOR_MINOR:
440 case FSID_ENCODE_DEV:
441 return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV;
442 case FSID_NUM:
443 return exp->ex_flags & NFSEXP_FSID;
444 case FSID_UUID8:
445 case FSID_UUID16:
446 if (!is_root_export(exp))
447 return 0;
448 /* fall through */
449 case FSID_UUID4_INUM:
450 case FSID_UUID16_INUM:
451 return exp->ex_uuid != NULL;
452 }
453 return 1;
454}
455
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400456
457static 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 -0700458{
NeilBrownb41eeef2007-05-09 02:34:57 -0700459 u8 version;
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400460 u8 fsid_type;
461retry:
NeilBrownb41eeef2007-05-09 02:34:57 -0700462 version = 1;
NeilBrown7e405362006-06-30 01:56:12 -0700463 if (ref_fh && ref_fh->fh_export == exp) {
NeilBrown982aedf2007-02-14 00:33:11 -0800464 version = ref_fh->fh_handle.fh_version;
NeilBrownb41eeef2007-05-09 02:34:57 -0700465 fsid_type = ref_fh->fh_handle.fh_fsid_type;
466
NeilBrownb41eeef2007-05-09 02:34:57 -0700467 ref_fh = NULL;
468
469 switch (version) {
470 case 0xca:
NeilBrownaf6a4e22007-02-14 00:33:12 -0800471 fsid_type = FSID_DEV;
NeilBrownb41eeef2007-05-09 02:34:57 -0700472 break;
473 case 1:
474 break;
475 default:
476 goto retry;
477 }
478
J. Bruce Fields8e498752009-09-02 19:31:32 -0400479 /*
480 * As the fsid -> filesystem mapping was guided by
481 * user-space, there is no guarantee that the filesystem
482 * actually supports that fsid type. If it doesn't we
483 * loop around again without ref_fh set.
NeilBrown982aedf2007-02-14 00:33:11 -0800484 */
J. Bruce Fields8e498752009-09-02 19:31:32 -0400485 if (!fsid_type_ok_for_exp(fsid_type, exp))
486 goto retry;
Steve Dickson30fa8c02009-01-07 16:54:30 -0500487 } else if (exp->ex_flags & NFSEXP_FSID) {
488 fsid_type = FSID_NUM;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800489 } else if (exp->ex_uuid) {
490 if (fhp->fh_maxsize >= 64) {
J. Bruce Fields8e498752009-09-02 19:31:32 -0400491 if (is_root_export(exp))
NeilBrownaf6a4e22007-02-14 00:33:12 -0800492 fsid_type = FSID_UUID16;
493 else
494 fsid_type = FSID_UUID16_INUM;
495 } else {
J. Bruce Fields8e498752009-09-02 19:31:32 -0400496 if (is_root_export(exp))
NeilBrownaf6a4e22007-02-14 00:33:12 -0800497 fsid_type = FSID_UUID8;
498 else
499 fsid_type = FSID_UUID4_INUM;
500 }
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400501 } else if (!old_valid_dev(exp_sb(exp)->s_dev))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502 /* for newer device numbers, we must use a newer fsid format */
NeilBrownaf6a4e22007-02-14 00:33:12 -0800503 fsid_type = FSID_ENCODE_DEV;
NeilBrown982aedf2007-02-14 00:33:11 -0800504 else
NeilBrownaf6a4e22007-02-14 00:33:12 -0800505 fsid_type = FSID_DEV;
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400506 fhp->fh_handle.fh_version = version;
507 if (version)
508 fhp->fh_handle.fh_fsid_type = fsid_type;
509}
510
511__be32
512fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
513 struct svc_fh *ref_fh)
514{
515 /* ref_fh is a reference file handle.
516 * if it is non-null and for the same filesystem, then we should compose
517 * a filehandle which is of the same version, where possible.
518 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
519 * Then create a 32byte filehandle using nfs_fhbase_old
520 *
521 */
522
523 struct inode * inode = dentry->d_inode;
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400524 dev_t ex_dev = exp_sb(exp)->s_dev;
525
Al Viro97e47fa2013-09-16 10:57:01 -0400526 dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %pd2, ino=%ld)\n",
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400527 MAJOR(ex_dev), MINOR(ex_dev),
528 (long) exp->ex_path.dentry->d_inode->i_ino,
Al Viro97e47fa2013-09-16 10:57:01 -0400529 dentry,
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400530 (inode ? inode->i_ino : 0));
531
532 /* Choose filehandle version and fsid type based on
533 * the reference filehandle (if it is in the same export)
534 * or the export options.
535 */
536 set_version_and_fsid_type(fhp, exp, ref_fh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537
538 if (ref_fh == fhp)
539 fh_put(ref_fh);
540
541 if (fhp->fh_locked || fhp->fh_dentry) {
Al Viro97e47fa2013-09-16 10:57:01 -0400542 printk(KERN_ERR "fh_compose: fh %pd2 not initialized!\n",
543 dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 }
545 if (fhp->fh_maxsize < NFS_FHSIZE)
Al Viro97e47fa2013-09-16 10:57:01 -0400546 printk(KERN_ERR "fh_compose: called with maxsize %d! %pd2\n",
NeilBrown982aedf2007-02-14 00:33:11 -0800547 fhp->fh_maxsize,
Al Viro97e47fa2013-09-16 10:57:01 -0400548 dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549
550 fhp->fh_dentry = dget(dentry); /* our internal copy */
Kinglong Meebf18f162014-06-10 22:06:44 +0800551 fhp->fh_export = exp_get(exp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552
J. Bruce Fieldsbc6c53d2009-09-02 19:50:40 -0400553 if (fhp->fh_handle.fh_version == 0xca) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 /* old style filehandle please */
555 memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
556 fhp->fh_handle.fh_size = NFS_FHSIZE;
557 fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
558 fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev);
559 fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
NeilBrown982aedf2007-02-14 00:33:11 -0800560 fhp->fh_handle.ofh_xino =
Jan Blunck54775492008-02-14 19:38:39 -0800561 ino_t_to_u32(exp->ex_path.dentry->d_inode->i_ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
563 if (inode)
564 _fh_update_old(dentry, exp, &fhp->fh_handle);
565 } else {
Christoph Hellwig5409e462014-05-07 13:49:44 +0200566 fhp->fh_handle.fh_size =
567 key_len(fhp->fh_handle.fh_fsid_type) + 4;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 fhp->fh_handle.fh_auth_type = 0;
Christoph Hellwig5409e462014-05-07 13:49:44 +0200569
570 mk_fsid(fhp->fh_handle.fh_fsid_type,
571 fhp->fh_handle.fh_fsid,
572 ex_dev,
Jan Blunck54775492008-02-14 19:38:39 -0800573 exp->ex_path.dentry->d_inode->i_ino,
NeilBrownaf6a4e22007-02-14 00:33:12 -0800574 exp->ex_fsid, exp->ex_uuid);
575
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700576 if (inode)
577 _fh_update(fhp, exp, dentry);
Namjae Jeon216b6cb2012-08-29 10:10:10 -0400578 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID) {
J. Bruce Fields1be10a82009-09-04 11:59:32 -0400579 fh_put(fhp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580 return nfserr_opnotsupp;
J. Bruce Fields1be10a82009-09-04 11:59:32 -0400581 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582 }
583
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 return 0;
585}
586
587/*
588 * Update file handle information after changing a dentry.
589 * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
590 */
Al Viro83b11342006-10-19 23:28:55 -0700591__be32
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592fh_update(struct svc_fh *fhp)
593{
594 struct dentry *dentry;
NeilBrown982aedf2007-02-14 00:33:11 -0800595
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 if (!fhp->fh_dentry)
597 goto out_bad;
598
599 dentry = fhp->fh_dentry;
600 if (!dentry->d_inode)
601 goto out_negative;
602 if (fhp->fh_handle.fh_version != 1) {
603 _fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
604 } else {
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700605 if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT)
J. Bruce Fields49e73722013-09-12 09:31:39 -0400606 return 0;
Christoph Hellwig6e91ea22007-10-21 16:42:03 -0700607
608 _fh_update(fhp, fhp->fh_export, dentry);
Namjae Jeon216b6cb2012-08-29 10:10:10 -0400609 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 return nfserr_opnotsupp;
611 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613out_bad:
614 printk(KERN_ERR "fh_update: fh not verified!\n");
J. Bruce Fields49e73722013-09-12 09:31:39 -0400615 return nfserr_serverfault;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616out_negative:
Al Viro97e47fa2013-09-16 10:57:01 -0400617 printk(KERN_ERR "fh_update: %pd2 still negative!\n",
618 dentry);
J. Bruce Fields49e73722013-09-12 09:31:39 -0400619 return nfserr_serverfault;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620}
621
622/*
623 * Release a file handle.
624 */
625void
626fh_put(struct svc_fh *fhp)
627{
628 struct dentry * dentry = fhp->fh_dentry;
629 struct svc_export * exp = fhp->fh_export;
630 if (dentry) {
631 fh_unlock(fhp);
632 fhp->fh_dentry = NULL;
633 dput(dentry);
634#ifdef CONFIG_NFSD_V3
635 fhp->fh_pre_saved = 0;
636 fhp->fh_post_saved = 0;
637#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638 }
Jan Kara4a55c102012-06-12 16:20:33 +0200639 fh_drop_write(fhp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 if (exp) {
Stanislav Kinsburskya09581f2012-03-28 19:09:22 +0400641 exp_put(exp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642 fhp->fh_export = NULL;
643 }
644 return;
645}
646
647/*
648 * Shorthand for dprintk()'s
649 */
650char * SVCFH_fmt(struct svc_fh *fhp)
651{
652 struct knfsd_fh *fh = &fhp->fh_handle;
653
654 static char buf[80];
655 sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x",
656 fh->fh_size,
657 fh->fh_base.fh_pad[0],
658 fh->fh_base.fh_pad[1],
659 fh->fh_base.fh_pad[2],
660 fh->fh_base.fh_pad[3],
661 fh->fh_base.fh_pad[4],
662 fh->fh_base.fh_pad[5]);
663 return buf;
664}
NeilBrownaf6a4e22007-02-14 00:33:12 -0800665
666enum fsid_source fsid_source(struct svc_fh *fhp)
667{
668 if (fhp->fh_handle.fh_version != 1)
669 return FSIDSOURCE_DEV;
670 switch(fhp->fh_handle.fh_fsid_type) {
671 case FSID_DEV:
672 case FSID_ENCODE_DEV:
673 case FSID_MAJOR_MINOR:
J. Bruce Fields8e498752009-09-02 19:31:32 -0400674 if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV)
Neil Brownb8da0d12007-09-05 17:22:13 -0400675 return FSIDSOURCE_DEV;
676 break;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800677 case FSID_NUM:
NeilBrownaf6a4e22007-02-14 00:33:12 -0800678 if (fhp->fh_export->ex_flags & NFSEXP_FSID)
679 return FSIDSOURCE_FSID;
Neil Brownb8da0d12007-09-05 17:22:13 -0400680 break;
681 default:
682 break;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800683 }
Neil Brownb8da0d12007-09-05 17:22:13 -0400684 /* either a UUID type filehandle, or the filehandle doesn't
685 * match the export.
686 */
687 if (fhp->fh_export->ex_flags & NFSEXP_FSID)
688 return FSIDSOURCE_FSID;
689 if (fhp->fh_export->ex_uuid)
690 return FSIDSOURCE_UUID;
691 return FSIDSOURCE_DEV;
NeilBrownaf6a4e22007-02-14 00:33:12 -0800692}