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1/*
2 * 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
10#include <linux/exportfs.h>
11
12#include <linux/sunrpc/svcauth_gss.h>
13#include "nfsd.h"
14#include "vfs.h"
15#include "auth.h"
16
17#define NFSDDBG_FACILITY NFSDDBG_FH
18
19
20/*
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);
37 while (tdentry != exp->ex_path.dentry && !IS_ROOT(tdentry)) {
38 /* make sure parents give x permission to user */
39 int err;
40 parent = dget_parent(tdentry);
41 err = inode_permission(d_inode(parent), MAY_EXEC);
42 if (err < 0) {
43 dput(parent);
44 break;
45 }
46 dput(tdentry);
47 tdentry = parent;
48 }
49 if (tdentry != exp->ex_path.dentry)
50 dprintk("nfsd_acceptable failed at %p %pd\n", tdentry, tdentry);
51 rv = (tdentry == exp->ex_path.dentry);
52 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 */
61static inline __be32
62nfsd_mode_check(struct svc_rqst *rqstp, struct dentry *dentry,
63 umode_t requested)
64{
65 umode_t mode = d_inode(dentry)->i_mode & S_IFMT;
66
67 if (requested == 0) /* the caller doesn't care */
68 return nfs_ok;
69 if (mode == requested) {
70 if (mode == S_IFDIR && !d_can_lookup(dentry)) {
71 WARN_ON_ONCE(1);
72 return nfserr_notdir;
73 }
74 return nfs_ok;
75 }
76 /*
77 * v4 has an error more specific than err_notdir which we should
78 * return in preference to err_notdir:
79 */
80 if (rqstp->rq_vers == 4 && mode == S_IFLNK)
81 return nfserr_symlink;
82 if (requested == S_IFDIR)
83 return nfserr_notdir;
84 if (mode == S_IFDIR)
85 return nfserr_isdir;
86 return nfserr_inval;
87}
88
89static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp,
90 struct svc_export *exp)
91{
92 int flags = nfsexp_flags(rqstp, exp);
93
94 /* Check if the request originated from a secure port. */
95 if (!test_bit(RQ_SECURE, &rqstp->rq_flags) && !(flags & NFSEXP_INSECURE_PORT)) {
96 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
97 dprintk("nfsd: request from insecure port %s!\n",
98 svc_print_addr(rqstp, buf, sizeof(buf)));
99 return nfserr_perm;
100 }
101
102 /* Set user creds for this exportpoint */
103 return nfserrno(nfsd_setuser(rqstp, exp));
104}
105
106static inline __be32 check_pseudo_root(struct svc_rqst *rqstp,
107 struct dentry *dentry, struct svc_export *exp)
108{
109 if (!(exp->ex_flags & NFSEXP_V4ROOT))
110 return nfs_ok;
111 /*
112 * v2/v3 clients have no need for the V4ROOT export--they use
113 * the mount protocl instead; also, further V4ROOT checks may be
114 * in v4-specific code, in which case v2/v3 clients could bypass
115 * them.
116 */
117 if (!nfsd_v4client(rqstp))
118 return nfserr_stale;
119 /*
120 * We're exposing only the directories and symlinks that have to be
121 * traversed on the way to real exports:
122 */
123 if (unlikely(!d_is_dir(dentry) &&
124 !d_is_symlink(dentry)))
125 return nfserr_stale;
126 /*
127 * A pseudoroot export gives permission to access only one
128 * single directory; the kernel has to make another upcall
129 * before granting access to anything else under it:
130 */
131 if (unlikely(dentry != exp->ex_path.dentry))
132 return nfserr_stale;
133 return nfs_ok;
134}
135
136/*
137 * Use the given filehandle to look up the corresponding export and
138 * dentry. On success, the results are used to set fh_export and
139 * fh_dentry.
140 */
141static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp)
142{
143 struct knfsd_fh *fh = &fhp->fh_handle;
144 struct fid *fid = NULL, sfid;
145 struct svc_export *exp;
146 struct dentry *dentry;
147 int fileid_type;
148 int data_left = fh->fh_size/4;
149 __be32 error;
150
151 error = nfserr_stale;
152 if (rqstp->rq_vers > 2)
153 error = nfserr_badhandle;
154 if (rqstp->rq_vers == 4 && fh->fh_size == 0)
155 return nfserr_nofilehandle;
156
157 if (fh->fh_version == 1) {
158 int len;
159
160 if (--data_left < 0)
161 return error;
162 if (fh->fh_auth_type != 0)
163 return error;
164 len = key_len(fh->fh_fsid_type) / 4;
165 if (len == 0)
166 return error;
167 if (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
168 /* deprecated, convert to type 3 */
169 len = key_len(FSID_ENCODE_DEV)/4;
170 fh->fh_fsid_type = FSID_ENCODE_DEV;
171 /*
172 * struct knfsd_fh uses host-endian fields, which are
173 * sometimes used to hold net-endian values. This
174 * confuses sparse, so we must use __force here to
175 * keep it from complaining.
176 */
177 fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl((__force __be32)fh->fh_fsid[0]),
178 ntohl((__force __be32)fh->fh_fsid[1])));
179 fh->fh_fsid[1] = fh->fh_fsid[2];
180 }
181 data_left -= len;
182 if (data_left < 0)
183 return error;
184 exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_fsid);
185 fid = (struct fid *)(fh->fh_fsid + len);
186 } else {
187 __u32 tfh[2];
188 dev_t xdev;
189 ino_t xino;
190
191 if (fh->fh_size != NFS_FHSIZE)
192 return error;
193 /* assume old filehandle format */
194 xdev = old_decode_dev(fh->ofh_xdev);
195 xino = u32_to_ino_t(fh->ofh_xino);
196 mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
197 exp = rqst_exp_find(rqstp, FSID_DEV, tfh);
198 }
199
200 error = nfserr_stale;
201 if (PTR_ERR(exp) == -ENOENT)
202 return error;
203
204 if (IS_ERR(exp))
205 return nfserrno(PTR_ERR(exp));
206
207 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) {
208 /* Elevate privileges so that the lack of 'r' or 'x'
209 * permission on some parent directory will
210 * not stop exportfs_decode_fh from being able
211 * to reconnect a directory into the dentry cache.
212 * The same problem can affect "SUBTREECHECK" exports,
213 * but as nfsd_acceptable depends on correct
214 * access control settings being in effect, we cannot
215 * fix that case easily.
216 */
217 struct cred *new = prepare_creds();
218 if (!new) {
219 error = nfserrno(-ENOMEM);
220 goto out;
221 }
222 new->cap_effective =
223 cap_raise_nfsd_set(new->cap_effective,
224 new->cap_permitted);
225 put_cred(override_creds(new));
226 put_cred(new);
227 } else {
228 error = nfsd_setuser_and_check_port(rqstp, exp);
229 if (error)
230 goto out;
231 }
232
233 /*
234 * Look up the dentry using the NFS file handle.
235 */
236 error = nfserr_stale;
237 if (rqstp->rq_vers > 2)
238 error = nfserr_badhandle;
239
240 if (fh->fh_version != 1) {
241 sfid.i32.ino = fh->ofh_ino;
242 sfid.i32.gen = fh->ofh_generation;
243 sfid.i32.parent_ino = fh->ofh_dirino;
244 fid = &sfid;
245 data_left = 3;
246 if (fh->ofh_dirino == 0)
247 fileid_type = FILEID_INO32_GEN;
248 else
249 fileid_type = FILEID_INO32_GEN_PARENT;
250 } else
251 fileid_type = fh->fh_fileid_type;
252
253 if (fileid_type == FILEID_ROOT)
254 dentry = dget(exp->ex_path.dentry);
255 else {
256 dentry = exportfs_decode_fh(exp->ex_path.mnt, fid,
257 data_left, fileid_type,
258 nfsd_acceptable, exp);
259 }
260 if (dentry == NULL)
261 goto out;
262 if (IS_ERR(dentry)) {
263 if (PTR_ERR(dentry) != -EINVAL)
264 error = nfserrno(PTR_ERR(dentry));
265 goto out;
266 }
267
268 if (d_is_dir(dentry) &&
269 (dentry->d_flags & DCACHE_DISCONNECTED)) {
270 printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %pd2\n",
271 dentry);
272 }
273
274 fhp->fh_dentry = dentry;
275 fhp->fh_export = exp;
276 return 0;
277out:
278 exp_put(exp);
279 return error;
280}
281
282/**
283 * fh_verify - filehandle lookup and access checking
284 * @rqstp: pointer to current rpc request
285 * @fhp: filehandle to be verified
286 * @type: expected type of object pointed to by filehandle
287 * @access: type of access needed to object
288 *
289 * Look up a dentry from the on-the-wire filehandle, check the client's
290 * access to the export, and set the current task's credentials.
291 *
292 * Regardless of success or failure of fh_verify(), fh_put() should be
293 * called on @fhp when the caller is finished with the filehandle.
294 *
295 * fh_verify() may be called multiple times on a given filehandle, for
296 * example, when processing an NFSv4 compound. The first call will look
297 * up a dentry using the on-the-wire filehandle. Subsequent calls will
298 * skip the lookup and just perform the other checks and possibly change
299 * the current task's credentials.
300 *
301 * @type specifies the type of object expected using one of the S_IF*
302 * constants defined in include/linux/stat.h. The caller may use zero
303 * to indicate that it doesn't care, or a negative integer to indicate
304 * that it expects something not of the given type.
305 *
306 * @access is formed from the NFSD_MAY_* constants defined in
307 * fs/nfsd/vfs.h.
308 */
309__be32
310fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, int access)
311{
312 struct svc_export *exp;
313 struct dentry *dentry;
314 __be32 error;
315
316 dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp));
317
318 if (!fhp->fh_dentry) {
319 error = nfsd_set_fh_dentry(rqstp, fhp);
320 if (error)
321 goto out;
322 }
323 dentry = fhp->fh_dentry;
324 exp = fhp->fh_export;
325 /*
326 * We still have to do all these permission checks, even when
327 * fh_dentry is already set:
328 * - fh_verify may be called multiple times with different
329 * "access" arguments (e.g. nfsd_proc_create calls
330 * fh_verify(...,NFSD_MAY_EXEC) first, then later (in
331 * nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE).
332 * - in the NFSv4 case, the filehandle may have been filled
333 * in by fh_compose, and given a dentry, but further
334 * compound operations performed with that filehandle
335 * still need permissions checks. In the worst case, a
336 * mountpoint crossing may have changed the export
337 * options, and we may now need to use a different uid
338 * (for example, if different id-squashing options are in
339 * effect on the new filesystem).
340 */
341 error = check_pseudo_root(rqstp, dentry, exp);
342 if (error)
343 goto out;
344
345 error = nfsd_setuser_and_check_port(rqstp, exp);
346 if (error)
347 goto out;
348
349 error = nfsd_mode_check(rqstp, dentry, type);
350 if (error)
351 goto out;
352
353 /*
354 * pseudoflavor restrictions are not enforced on NLM,
355 * which clients virtually always use auth_sys for,
356 * even while using RPCSEC_GSS for NFS.
357 */
358 if (access & NFSD_MAY_LOCK || access & NFSD_MAY_BYPASS_GSS)
359 goto skip_pseudoflavor_check;
360 /*
361 * Clients may expect to be able to use auth_sys during mount,
362 * even if they use gss for everything else; see section 2.3.2
363 * of rfc 2623.
364 */
365 if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT
366 && exp->ex_path.dentry == dentry)
367 goto skip_pseudoflavor_check;
368
369 error = check_nfsd_access(exp, rqstp);
370 if (error)
371 goto out;
372
373skip_pseudoflavor_check:
374 /* Finally, check access permissions. */
375 error = nfsd_permission(rqstp, exp, dentry, access);
376
377 if (error) {
378 dprintk("fh_verify: %pd2 permission failure, "
379 "acc=%x, error=%d\n",
380 dentry,
381 access, ntohl(error));
382 }
383out:
384 if (error == nfserr_stale)
385 nfsdstats.fh_stale++;
386 return error;
387}
388
389
390/*
391 * Compose a file handle for an NFS reply.
392 *
393 * Note that when first composed, the dentry may not yet have
394 * an inode. In this case a call to fh_update should be made
395 * before the fh goes out on the wire ...
396 */
397static void _fh_update(struct svc_fh *fhp, struct svc_export *exp,
398 struct dentry *dentry)
399{
400 if (dentry != exp->ex_path.dentry) {
401 struct fid *fid = (struct fid *)
402 (fhp->fh_handle.fh_fsid + fhp->fh_handle.fh_size/4 - 1);
403 int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
404 int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK);
405
406 fhp->fh_handle.fh_fileid_type =
407 exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck);
408 fhp->fh_handle.fh_size += maxsize * 4;
409 } else {
410 fhp->fh_handle.fh_fileid_type = FILEID_ROOT;
411 }
412}
413
414/*
415 * for composing old style file handles
416 */
417static inline void _fh_update_old(struct dentry *dentry,
418 struct svc_export *exp,
419 struct knfsd_fh *fh)
420{
421 fh->ofh_ino = ino_t_to_u32(d_inode(dentry)->i_ino);
422 fh->ofh_generation = d_inode(dentry)->i_generation;
423 if (d_is_dir(dentry) ||
424 (exp->ex_flags & NFSEXP_NOSUBTREECHECK))
425 fh->ofh_dirino = 0;
426}
427
428static bool is_root_export(struct svc_export *exp)
429{
430 return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root;
431}
432
433static struct super_block *exp_sb(struct svc_export *exp)
434{
435 return exp->ex_path.dentry->d_sb;
436}
437
438static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp)
439{
440 switch (fsid_type) {
441 case FSID_DEV:
442 if (!old_valid_dev(exp_sb(exp)->s_dev))
443 return 0;
444 /* FALL THROUGH */
445 case FSID_MAJOR_MINOR:
446 case FSID_ENCODE_DEV:
447 return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV;
448 case FSID_NUM:
449 return exp->ex_flags & NFSEXP_FSID;
450 case FSID_UUID8:
451 case FSID_UUID16:
452 if (!is_root_export(exp))
453 return 0;
454 /* fall through */
455 case FSID_UUID4_INUM:
456 case FSID_UUID16_INUM:
457 return exp->ex_uuid != NULL;
458 }
459 return 1;
460}
461
462
463static void set_version_and_fsid_type(struct svc_fh *fhp, struct svc_export *exp, struct svc_fh *ref_fh)
464{
465 u8 version;
466 u8 fsid_type;
467retry:
468 version = 1;
469 if (ref_fh && ref_fh->fh_export == exp) {
470 version = ref_fh->fh_handle.fh_version;
471 fsid_type = ref_fh->fh_handle.fh_fsid_type;
472
473 ref_fh = NULL;
474
475 switch (version) {
476 case 0xca:
477 fsid_type = FSID_DEV;
478 break;
479 case 1:
480 break;
481 default:
482 goto retry;
483 }
484
485 /*
486 * As the fsid -> filesystem mapping was guided by
487 * user-space, there is no guarantee that the filesystem
488 * actually supports that fsid type. If it doesn't we
489 * loop around again without ref_fh set.
490 */
491 if (!fsid_type_ok_for_exp(fsid_type, exp))
492 goto retry;
493 } else if (exp->ex_flags & NFSEXP_FSID) {
494 fsid_type = FSID_NUM;
495 } else if (exp->ex_uuid) {
496 if (fhp->fh_maxsize >= 64) {
497 if (is_root_export(exp))
498 fsid_type = FSID_UUID16;
499 else
500 fsid_type = FSID_UUID16_INUM;
501 } else {
502 if (is_root_export(exp))
503 fsid_type = FSID_UUID8;
504 else
505 fsid_type = FSID_UUID4_INUM;
506 }
507 } else if (!old_valid_dev(exp_sb(exp)->s_dev))
508 /* for newer device numbers, we must use a newer fsid format */
509 fsid_type = FSID_ENCODE_DEV;
510 else
511 fsid_type = FSID_DEV;
512 fhp->fh_handle.fh_version = version;
513 if (version)
514 fhp->fh_handle.fh_fsid_type = fsid_type;
515}
516
517__be32
518fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
519 struct svc_fh *ref_fh)
520{
521 /* ref_fh is a reference file handle.
522 * if it is non-null and for the same filesystem, then we should compose
523 * a filehandle which is of the same version, where possible.
524 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
525 * Then create a 32byte filehandle using nfs_fhbase_old
526 *
527 */
528
529 struct inode * inode = d_inode(dentry);
530 dev_t ex_dev = exp_sb(exp)->s_dev;
531
532 dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %pd2, ino=%ld)\n",
533 MAJOR(ex_dev), MINOR(ex_dev),
534 (long) d_inode(exp->ex_path.dentry)->i_ino,
535 dentry,
536 (inode ? inode->i_ino : 0));
537
538 /* Choose filehandle version and fsid type based on
539 * the reference filehandle (if it is in the same export)
540 * or the export options.
541 */
542 set_version_and_fsid_type(fhp, exp, ref_fh);
543
544 if (ref_fh == fhp)
545 fh_put(ref_fh);
546
547 if (fhp->fh_locked || fhp->fh_dentry) {
548 printk(KERN_ERR "fh_compose: fh %pd2 not initialized!\n",
549 dentry);
550 }
551 if (fhp->fh_maxsize < NFS_FHSIZE)
552 printk(KERN_ERR "fh_compose: called with maxsize %d! %pd2\n",
553 fhp->fh_maxsize,
554 dentry);
555
556 fhp->fh_dentry = dget(dentry); /* our internal copy */
557 fhp->fh_export = exp_get(exp);
558
559 if (fhp->fh_handle.fh_version == 0xca) {
560 /* old style filehandle please */
561 memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
562 fhp->fh_handle.fh_size = NFS_FHSIZE;
563 fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
564 fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev);
565 fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
566 fhp->fh_handle.ofh_xino =
567 ino_t_to_u32(d_inode(exp->ex_path.dentry)->i_ino);
568 fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
569 if (inode)
570 _fh_update_old(dentry, exp, &fhp->fh_handle);
571 } else {
572 fhp->fh_handle.fh_size =
573 key_len(fhp->fh_handle.fh_fsid_type) + 4;
574 fhp->fh_handle.fh_auth_type = 0;
575
576 mk_fsid(fhp->fh_handle.fh_fsid_type,
577 fhp->fh_handle.fh_fsid,
578 ex_dev,
579 d_inode(exp->ex_path.dentry)->i_ino,
580 exp->ex_fsid, exp->ex_uuid);
581
582 if (inode)
583 _fh_update(fhp, exp, dentry);
584 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID) {
585 fh_put(fhp);
586 return nfserr_opnotsupp;
587 }
588 }
589
590 return 0;
591}
592
593/*
594 * Update file handle information after changing a dentry.
595 * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
596 */
597__be32
598fh_update(struct svc_fh *fhp)
599{
600 struct dentry *dentry;
601
602 if (!fhp->fh_dentry)
603 goto out_bad;
604
605 dentry = fhp->fh_dentry;
606 if (d_really_is_negative(dentry))
607 goto out_negative;
608 if (fhp->fh_handle.fh_version != 1) {
609 _fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
610 } else {
611 if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT)
612 return 0;
613
614 _fh_update(fhp, fhp->fh_export, dentry);
615 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID)
616 return nfserr_opnotsupp;
617 }
618 return 0;
619out_bad:
620 printk(KERN_ERR "fh_update: fh not verified!\n");
621 return nfserr_serverfault;
622out_negative:
623 printk(KERN_ERR "fh_update: %pd2 still negative!\n",
624 dentry);
625 return nfserr_serverfault;
626}
627
628/*
629 * Release a file handle.
630 */
631void
632fh_put(struct svc_fh *fhp)
633{
634 struct dentry * dentry = fhp->fh_dentry;
635 struct svc_export * exp = fhp->fh_export;
636 if (dentry) {
637 fh_unlock(fhp);
638 fhp->fh_dentry = NULL;
639 dput(dentry);
640 fh_clear_wcc(fhp);
641 }
642 fh_drop_write(fhp);
643 if (exp) {
644 exp_put(exp);
645 fhp->fh_export = NULL;
646 }
647 return;
648}
649
650/*
651 * Shorthand for dprintk()'s
652 */
653char * SVCFH_fmt(struct svc_fh *fhp)
654{
655 struct knfsd_fh *fh = &fhp->fh_handle;
656
657 static char buf[80];
658 sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x",
659 fh->fh_size,
660 fh->fh_base.fh_pad[0],
661 fh->fh_base.fh_pad[1],
662 fh->fh_base.fh_pad[2],
663 fh->fh_base.fh_pad[3],
664 fh->fh_base.fh_pad[4],
665 fh->fh_base.fh_pad[5]);
666 return buf;
667}
668
669enum fsid_source fsid_source(struct svc_fh *fhp)
670{
671 if (fhp->fh_handle.fh_version != 1)
672 return FSIDSOURCE_DEV;
673 switch(fhp->fh_handle.fh_fsid_type) {
674 case FSID_DEV:
675 case FSID_ENCODE_DEV:
676 case FSID_MAJOR_MINOR:
677 if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV)
678 return FSIDSOURCE_DEV;
679 break;
680 case FSID_NUM:
681 if (fhp->fh_export->ex_flags & NFSEXP_FSID)
682 return FSIDSOURCE_FSID;
683 break;
684 default:
685 break;
686 }
687 /* either a UUID type filehandle, or the filehandle doesn't
688 * match the export.
689 */
690 if (fhp->fh_export->ex_flags & NFSEXP_FSID)
691 return FSIDSOURCE_FSID;
692 if (fhp->fh_export->ex_uuid)
693 return FSIDSOURCE_UUID;
694 return FSIDSOURCE_DEV;
695}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * NFS server file handle treatment.
4 *
5 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
6 * Portions Copyright (C) 1999 G. Allen Morris III <gam3@acm.org>
7 * Extensive rewrite by Neil Brown <neilb@cse.unsw.edu.au> Southern-Spring 1999
8 * ... and again Southern-Winter 2001 to support export_operations
9 */
10
11#include <linux/exportfs.h>
12
13#include <linux/sunrpc/svcauth_gss.h>
14#include "nfsd.h"
15#include "vfs.h"
16#include "auth.h"
17
18#define NFSDDBG_FACILITY NFSDDBG_FH
19
20
21/*
22 * our acceptability function.
23 * if NOSUBTREECHECK, accept anything
24 * if not, require that we can walk up to exp->ex_dentry
25 * doing some checks on the 'x' bits
26 */
27static int nfsd_acceptable(void *expv, struct dentry *dentry)
28{
29 struct svc_export *exp = expv;
30 int rv;
31 struct dentry *tdentry;
32 struct dentry *parent;
33
34 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
35 return 1;
36
37 tdentry = dget(dentry);
38 while (tdentry != exp->ex_path.dentry && !IS_ROOT(tdentry)) {
39 /* make sure parents give x permission to user */
40 int err;
41 parent = dget_parent(tdentry);
42 err = inode_permission(d_inode(parent), MAY_EXEC);
43 if (err < 0) {
44 dput(parent);
45 break;
46 }
47 dput(tdentry);
48 tdentry = parent;
49 }
50 if (tdentry != exp->ex_path.dentry)
51 dprintk("nfsd_acceptable failed at %p %pd\n", tdentry, tdentry);
52 rv = (tdentry == exp->ex_path.dentry);
53 dput(tdentry);
54 return rv;
55}
56
57/* Type check. The correct error return for type mismatches does not seem to be
58 * generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a
59 * comment in the NFSv3 spec says this is incorrect (implementation notes for
60 * the write call).
61 */
62static inline __be32
63nfsd_mode_check(struct svc_rqst *rqstp, struct dentry *dentry,
64 umode_t requested)
65{
66 umode_t mode = d_inode(dentry)->i_mode & S_IFMT;
67
68 if (requested == 0) /* the caller doesn't care */
69 return nfs_ok;
70 if (mode == requested) {
71 if (mode == S_IFDIR && !d_can_lookup(dentry)) {
72 WARN_ON_ONCE(1);
73 return nfserr_notdir;
74 }
75 return nfs_ok;
76 }
77 /*
78 * v4 has an error more specific than err_notdir which we should
79 * return in preference to err_notdir:
80 */
81 if (rqstp->rq_vers == 4 && mode == S_IFLNK)
82 return nfserr_symlink;
83 if (requested == S_IFDIR)
84 return nfserr_notdir;
85 if (mode == S_IFDIR)
86 return nfserr_isdir;
87 return nfserr_inval;
88}
89
90static bool nfsd_originating_port_ok(struct svc_rqst *rqstp, int flags)
91{
92 if (flags & NFSEXP_INSECURE_PORT)
93 return true;
94 /* We don't require gss requests to use low ports: */
95 if (rqstp->rq_cred.cr_flavor >= RPC_AUTH_GSS)
96 return true;
97 return test_bit(RQ_SECURE, &rqstp->rq_flags);
98}
99
100static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp,
101 struct svc_export *exp)
102{
103 int flags = nfsexp_flags(rqstp, exp);
104
105 /* Check if the request originated from a secure port. */
106 if (!nfsd_originating_port_ok(rqstp, flags)) {
107 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
108 dprintk("nfsd: request from insecure port %s!\n",
109 svc_print_addr(rqstp, buf, sizeof(buf)));
110 return nfserr_perm;
111 }
112
113 /* Set user creds for this exportpoint */
114 return nfserrno(nfsd_setuser(rqstp, exp));
115}
116
117static inline __be32 check_pseudo_root(struct svc_rqst *rqstp,
118 struct dentry *dentry, struct svc_export *exp)
119{
120 if (!(exp->ex_flags & NFSEXP_V4ROOT))
121 return nfs_ok;
122 /*
123 * v2/v3 clients have no need for the V4ROOT export--they use
124 * the mount protocl instead; also, further V4ROOT checks may be
125 * in v4-specific code, in which case v2/v3 clients could bypass
126 * them.
127 */
128 if (!nfsd_v4client(rqstp))
129 return nfserr_stale;
130 /*
131 * We're exposing only the directories and symlinks that have to be
132 * traversed on the way to real exports:
133 */
134 if (unlikely(!d_is_dir(dentry) &&
135 !d_is_symlink(dentry)))
136 return nfserr_stale;
137 /*
138 * A pseudoroot export gives permission to access only one
139 * single directory; the kernel has to make another upcall
140 * before granting access to anything else under it:
141 */
142 if (unlikely(dentry != exp->ex_path.dentry))
143 return nfserr_stale;
144 return nfs_ok;
145}
146
147/*
148 * Use the given filehandle to look up the corresponding export and
149 * dentry. On success, the results are used to set fh_export and
150 * fh_dentry.
151 */
152static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp)
153{
154 struct knfsd_fh *fh = &fhp->fh_handle;
155 struct fid *fid = NULL, sfid;
156 struct svc_export *exp;
157 struct dentry *dentry;
158 int fileid_type;
159 int data_left = fh->fh_size/4;
160 __be32 error;
161
162 error = nfserr_stale;
163 if (rqstp->rq_vers > 2)
164 error = nfserr_badhandle;
165 if (rqstp->rq_vers == 4 && fh->fh_size == 0)
166 return nfserr_nofilehandle;
167
168 if (fh->fh_version == 1) {
169 int len;
170
171 if (--data_left < 0)
172 return error;
173 if (fh->fh_auth_type != 0)
174 return error;
175 len = key_len(fh->fh_fsid_type) / 4;
176 if (len == 0)
177 return error;
178 if (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
179 /* deprecated, convert to type 3 */
180 len = key_len(FSID_ENCODE_DEV)/4;
181 fh->fh_fsid_type = FSID_ENCODE_DEV;
182 /*
183 * struct knfsd_fh uses host-endian fields, which are
184 * sometimes used to hold net-endian values. This
185 * confuses sparse, so we must use __force here to
186 * keep it from complaining.
187 */
188 fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl((__force __be32)fh->fh_fsid[0]),
189 ntohl((__force __be32)fh->fh_fsid[1])));
190 fh->fh_fsid[1] = fh->fh_fsid[2];
191 }
192 data_left -= len;
193 if (data_left < 0)
194 return error;
195 exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_fsid);
196 fid = (struct fid *)(fh->fh_fsid + len);
197 } else {
198 __u32 tfh[2];
199 dev_t xdev;
200 ino_t xino;
201
202 if (fh->fh_size != NFS_FHSIZE)
203 return error;
204 /* assume old filehandle format */
205 xdev = old_decode_dev(fh->ofh_xdev);
206 xino = u32_to_ino_t(fh->ofh_xino);
207 mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
208 exp = rqst_exp_find(rqstp, FSID_DEV, tfh);
209 }
210
211 error = nfserr_stale;
212 if (PTR_ERR(exp) == -ENOENT)
213 return error;
214
215 if (IS_ERR(exp))
216 return nfserrno(PTR_ERR(exp));
217
218 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) {
219 /* Elevate privileges so that the lack of 'r' or 'x'
220 * permission on some parent directory will
221 * not stop exportfs_decode_fh from being able
222 * to reconnect a directory into the dentry cache.
223 * The same problem can affect "SUBTREECHECK" exports,
224 * but as nfsd_acceptable depends on correct
225 * access control settings being in effect, we cannot
226 * fix that case easily.
227 */
228 struct cred *new = prepare_creds();
229 if (!new) {
230 error = nfserrno(-ENOMEM);
231 goto out;
232 }
233 new->cap_effective =
234 cap_raise_nfsd_set(new->cap_effective,
235 new->cap_permitted);
236 put_cred(override_creds(new));
237 put_cred(new);
238 } else {
239 error = nfsd_setuser_and_check_port(rqstp, exp);
240 if (error)
241 goto out;
242 }
243
244 /*
245 * Look up the dentry using the NFS file handle.
246 */
247 error = nfserr_stale;
248 if (rqstp->rq_vers > 2)
249 error = nfserr_badhandle;
250
251 if (fh->fh_version != 1) {
252 sfid.i32.ino = fh->ofh_ino;
253 sfid.i32.gen = fh->ofh_generation;
254 sfid.i32.parent_ino = fh->ofh_dirino;
255 fid = &sfid;
256 data_left = 3;
257 if (fh->ofh_dirino == 0)
258 fileid_type = FILEID_INO32_GEN;
259 else
260 fileid_type = FILEID_INO32_GEN_PARENT;
261 } else
262 fileid_type = fh->fh_fileid_type;
263
264 if (fileid_type == FILEID_ROOT)
265 dentry = dget(exp->ex_path.dentry);
266 else {
267 dentry = exportfs_decode_fh(exp->ex_path.mnt, fid,
268 data_left, fileid_type,
269 nfsd_acceptable, exp);
270 }
271 if (dentry == NULL)
272 goto out;
273 if (IS_ERR(dentry)) {
274 if (PTR_ERR(dentry) != -EINVAL)
275 error = nfserrno(PTR_ERR(dentry));
276 goto out;
277 }
278
279 if (d_is_dir(dentry) &&
280 (dentry->d_flags & DCACHE_DISCONNECTED)) {
281 printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %pd2\n",
282 dentry);
283 }
284
285 fhp->fh_dentry = dentry;
286 fhp->fh_export = exp;
287 return 0;
288out:
289 exp_put(exp);
290 return error;
291}
292
293/**
294 * fh_verify - filehandle lookup and access checking
295 * @rqstp: pointer to current rpc request
296 * @fhp: filehandle to be verified
297 * @type: expected type of object pointed to by filehandle
298 * @access: type of access needed to object
299 *
300 * Look up a dentry from the on-the-wire filehandle, check the client's
301 * access to the export, and set the current task's credentials.
302 *
303 * Regardless of success or failure of fh_verify(), fh_put() should be
304 * called on @fhp when the caller is finished with the filehandle.
305 *
306 * fh_verify() may be called multiple times on a given filehandle, for
307 * example, when processing an NFSv4 compound. The first call will look
308 * up a dentry using the on-the-wire filehandle. Subsequent calls will
309 * skip the lookup and just perform the other checks and possibly change
310 * the current task's credentials.
311 *
312 * @type specifies the type of object expected using one of the S_IF*
313 * constants defined in include/linux/stat.h. The caller may use zero
314 * to indicate that it doesn't care, or a negative integer to indicate
315 * that it expects something not of the given type.
316 *
317 * @access is formed from the NFSD_MAY_* constants defined in
318 * fs/nfsd/vfs.h.
319 */
320__be32
321fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, int access)
322{
323 struct svc_export *exp;
324 struct dentry *dentry;
325 __be32 error;
326
327 dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp));
328
329 if (!fhp->fh_dentry) {
330 error = nfsd_set_fh_dentry(rqstp, fhp);
331 if (error)
332 goto out;
333 }
334 dentry = fhp->fh_dentry;
335 exp = fhp->fh_export;
336 /*
337 * We still have to do all these permission checks, even when
338 * fh_dentry is already set:
339 * - fh_verify may be called multiple times with different
340 * "access" arguments (e.g. nfsd_proc_create calls
341 * fh_verify(...,NFSD_MAY_EXEC) first, then later (in
342 * nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE).
343 * - in the NFSv4 case, the filehandle may have been filled
344 * in by fh_compose, and given a dentry, but further
345 * compound operations performed with that filehandle
346 * still need permissions checks. In the worst case, a
347 * mountpoint crossing may have changed the export
348 * options, and we may now need to use a different uid
349 * (for example, if different id-squashing options are in
350 * effect on the new filesystem).
351 */
352 error = check_pseudo_root(rqstp, dentry, exp);
353 if (error)
354 goto out;
355
356 error = nfsd_setuser_and_check_port(rqstp, exp);
357 if (error)
358 goto out;
359
360 error = nfsd_mode_check(rqstp, dentry, type);
361 if (error)
362 goto out;
363
364 /*
365 * pseudoflavor restrictions are not enforced on NLM,
366 * which clients virtually always use auth_sys for,
367 * even while using RPCSEC_GSS for NFS.
368 */
369 if (access & NFSD_MAY_LOCK || access & NFSD_MAY_BYPASS_GSS)
370 goto skip_pseudoflavor_check;
371 /*
372 * Clients may expect to be able to use auth_sys during mount,
373 * even if they use gss for everything else; see section 2.3.2
374 * of rfc 2623.
375 */
376 if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT
377 && exp->ex_path.dentry == dentry)
378 goto skip_pseudoflavor_check;
379
380 error = check_nfsd_access(exp, rqstp);
381 if (error)
382 goto out;
383
384skip_pseudoflavor_check:
385 /* Finally, check access permissions. */
386 error = nfsd_permission(rqstp, exp, dentry, access);
387
388 if (error) {
389 dprintk("fh_verify: %pd2 permission failure, "
390 "acc=%x, error=%d\n",
391 dentry,
392 access, ntohl(error));
393 }
394out:
395 if (error == nfserr_stale)
396 nfsdstats.fh_stale++;
397 return error;
398}
399
400
401/*
402 * Compose a file handle for an NFS reply.
403 *
404 * Note that when first composed, the dentry may not yet have
405 * an inode. In this case a call to fh_update should be made
406 * before the fh goes out on the wire ...
407 */
408static void _fh_update(struct svc_fh *fhp, struct svc_export *exp,
409 struct dentry *dentry)
410{
411 if (dentry != exp->ex_path.dentry) {
412 struct fid *fid = (struct fid *)
413 (fhp->fh_handle.fh_fsid + fhp->fh_handle.fh_size/4 - 1);
414 int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
415 int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK);
416
417 fhp->fh_handle.fh_fileid_type =
418 exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck);
419 fhp->fh_handle.fh_size += maxsize * 4;
420 } else {
421 fhp->fh_handle.fh_fileid_type = FILEID_ROOT;
422 }
423}
424
425/*
426 * for composing old style file handles
427 */
428static inline void _fh_update_old(struct dentry *dentry,
429 struct svc_export *exp,
430 struct knfsd_fh *fh)
431{
432 fh->ofh_ino = ino_t_to_u32(d_inode(dentry)->i_ino);
433 fh->ofh_generation = d_inode(dentry)->i_generation;
434 if (d_is_dir(dentry) ||
435 (exp->ex_flags & NFSEXP_NOSUBTREECHECK))
436 fh->ofh_dirino = 0;
437}
438
439static bool is_root_export(struct svc_export *exp)
440{
441 return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root;
442}
443
444static struct super_block *exp_sb(struct svc_export *exp)
445{
446 return exp->ex_path.dentry->d_sb;
447}
448
449static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp)
450{
451 switch (fsid_type) {
452 case FSID_DEV:
453 if (!old_valid_dev(exp_sb(exp)->s_dev))
454 return false;
455 /* FALL THROUGH */
456 case FSID_MAJOR_MINOR:
457 case FSID_ENCODE_DEV:
458 return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV;
459 case FSID_NUM:
460 return exp->ex_flags & NFSEXP_FSID;
461 case FSID_UUID8:
462 case FSID_UUID16:
463 if (!is_root_export(exp))
464 return false;
465 /* fall through */
466 case FSID_UUID4_INUM:
467 case FSID_UUID16_INUM:
468 return exp->ex_uuid != NULL;
469 }
470 return true;
471}
472
473
474static void set_version_and_fsid_type(struct svc_fh *fhp, struct svc_export *exp, struct svc_fh *ref_fh)
475{
476 u8 version;
477 u8 fsid_type;
478retry:
479 version = 1;
480 if (ref_fh && ref_fh->fh_export == exp) {
481 version = ref_fh->fh_handle.fh_version;
482 fsid_type = ref_fh->fh_handle.fh_fsid_type;
483
484 ref_fh = NULL;
485
486 switch (version) {
487 case 0xca:
488 fsid_type = FSID_DEV;
489 break;
490 case 1:
491 break;
492 default:
493 goto retry;
494 }
495
496 /*
497 * As the fsid -> filesystem mapping was guided by
498 * user-space, there is no guarantee that the filesystem
499 * actually supports that fsid type. If it doesn't we
500 * loop around again without ref_fh set.
501 */
502 if (!fsid_type_ok_for_exp(fsid_type, exp))
503 goto retry;
504 } else if (exp->ex_flags & NFSEXP_FSID) {
505 fsid_type = FSID_NUM;
506 } else if (exp->ex_uuid) {
507 if (fhp->fh_maxsize >= 64) {
508 if (is_root_export(exp))
509 fsid_type = FSID_UUID16;
510 else
511 fsid_type = FSID_UUID16_INUM;
512 } else {
513 if (is_root_export(exp))
514 fsid_type = FSID_UUID8;
515 else
516 fsid_type = FSID_UUID4_INUM;
517 }
518 } else if (!old_valid_dev(exp_sb(exp)->s_dev))
519 /* for newer device numbers, we must use a newer fsid format */
520 fsid_type = FSID_ENCODE_DEV;
521 else
522 fsid_type = FSID_DEV;
523 fhp->fh_handle.fh_version = version;
524 if (version)
525 fhp->fh_handle.fh_fsid_type = fsid_type;
526}
527
528__be32
529fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
530 struct svc_fh *ref_fh)
531{
532 /* ref_fh is a reference file handle.
533 * if it is non-null and for the same filesystem, then we should compose
534 * a filehandle which is of the same version, where possible.
535 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
536 * Then create a 32byte filehandle using nfs_fhbase_old
537 *
538 */
539
540 struct inode * inode = d_inode(dentry);
541 dev_t ex_dev = exp_sb(exp)->s_dev;
542
543 dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %pd2, ino=%ld)\n",
544 MAJOR(ex_dev), MINOR(ex_dev),
545 (long) d_inode(exp->ex_path.dentry)->i_ino,
546 dentry,
547 (inode ? inode->i_ino : 0));
548
549 /* Choose filehandle version and fsid type based on
550 * the reference filehandle (if it is in the same export)
551 * or the export options.
552 */
553 set_version_and_fsid_type(fhp, exp, ref_fh);
554
555 if (ref_fh == fhp)
556 fh_put(ref_fh);
557
558 if (fhp->fh_locked || fhp->fh_dentry) {
559 printk(KERN_ERR "fh_compose: fh %pd2 not initialized!\n",
560 dentry);
561 }
562 if (fhp->fh_maxsize < NFS_FHSIZE)
563 printk(KERN_ERR "fh_compose: called with maxsize %d! %pd2\n",
564 fhp->fh_maxsize,
565 dentry);
566
567 fhp->fh_dentry = dget(dentry); /* our internal copy */
568 fhp->fh_export = exp_get(exp);
569
570 if (fhp->fh_handle.fh_version == 0xca) {
571 /* old style filehandle please */
572 memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
573 fhp->fh_handle.fh_size = NFS_FHSIZE;
574 fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
575 fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev);
576 fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
577 fhp->fh_handle.ofh_xino =
578 ino_t_to_u32(d_inode(exp->ex_path.dentry)->i_ino);
579 fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
580 if (inode)
581 _fh_update_old(dentry, exp, &fhp->fh_handle);
582 } else {
583 fhp->fh_handle.fh_size =
584 key_len(fhp->fh_handle.fh_fsid_type) + 4;
585 fhp->fh_handle.fh_auth_type = 0;
586
587 mk_fsid(fhp->fh_handle.fh_fsid_type,
588 fhp->fh_handle.fh_fsid,
589 ex_dev,
590 d_inode(exp->ex_path.dentry)->i_ino,
591 exp->ex_fsid, exp->ex_uuid);
592
593 if (inode)
594 _fh_update(fhp, exp, dentry);
595 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID) {
596 fh_put(fhp);
597 return nfserr_opnotsupp;
598 }
599 }
600
601 return 0;
602}
603
604/*
605 * Update file handle information after changing a dentry.
606 * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
607 */
608__be32
609fh_update(struct svc_fh *fhp)
610{
611 struct dentry *dentry;
612
613 if (!fhp->fh_dentry)
614 goto out_bad;
615
616 dentry = fhp->fh_dentry;
617 if (d_really_is_negative(dentry))
618 goto out_negative;
619 if (fhp->fh_handle.fh_version != 1) {
620 _fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
621 } else {
622 if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT)
623 return 0;
624
625 _fh_update(fhp, fhp->fh_export, dentry);
626 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID)
627 return nfserr_opnotsupp;
628 }
629 return 0;
630out_bad:
631 printk(KERN_ERR "fh_update: fh not verified!\n");
632 return nfserr_serverfault;
633out_negative:
634 printk(KERN_ERR "fh_update: %pd2 still negative!\n",
635 dentry);
636 return nfserr_serverfault;
637}
638
639/*
640 * Release a file handle.
641 */
642void
643fh_put(struct svc_fh *fhp)
644{
645 struct dentry * dentry = fhp->fh_dentry;
646 struct svc_export * exp = fhp->fh_export;
647 if (dentry) {
648 fh_unlock(fhp);
649 fhp->fh_dentry = NULL;
650 dput(dentry);
651 fh_clear_wcc(fhp);
652 }
653 fh_drop_write(fhp);
654 if (exp) {
655 exp_put(exp);
656 fhp->fh_export = NULL;
657 }
658 return;
659}
660
661/*
662 * Shorthand for dprintk()'s
663 */
664char * SVCFH_fmt(struct svc_fh *fhp)
665{
666 struct knfsd_fh *fh = &fhp->fh_handle;
667
668 static char buf[80];
669 sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x",
670 fh->fh_size,
671 fh->fh_base.fh_pad[0],
672 fh->fh_base.fh_pad[1],
673 fh->fh_base.fh_pad[2],
674 fh->fh_base.fh_pad[3],
675 fh->fh_base.fh_pad[4],
676 fh->fh_base.fh_pad[5]);
677 return buf;
678}
679
680enum fsid_source fsid_source(struct svc_fh *fhp)
681{
682 if (fhp->fh_handle.fh_version != 1)
683 return FSIDSOURCE_DEV;
684 switch(fhp->fh_handle.fh_fsid_type) {
685 case FSID_DEV:
686 case FSID_ENCODE_DEV:
687 case FSID_MAJOR_MINOR:
688 if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV)
689 return FSIDSOURCE_DEV;
690 break;
691 case FSID_NUM:
692 if (fhp->fh_export->ex_flags & NFSEXP_FSID)
693 return FSIDSOURCE_FSID;
694 break;
695 default:
696 break;
697 }
698 /* either a UUID type filehandle, or the filehandle doesn't
699 * match the export.
700 */
701 if (fhp->fh_export->ex_flags & NFSEXP_FSID)
702 return FSIDSOURCE_FSID;
703 if (fhp->fh_export->ex_uuid)
704 return FSIDSOURCE_UUID;
705 return FSIDSOURCE_DEV;
706}