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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
22
23
24
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
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
57
58
59
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)
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
78
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
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
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
113
114
115
116
117 if (!nfsd_v4client(rqstp))
118 return nfserr_stale;
119
120
121
122
123 if (unlikely(!d_is_dir(dentry) &&
124 !d_is_symlink(dentry)))
125 return nfserr_stale;
126
127
128
129
130
131 if (unlikely(dentry != exp->ex_path.dentry))
132 return nfserr_stale;
133 return nfs_ok;
134}
135
136
137
138
139
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
169 len = key_len(FSID_ENCODE_DEV)/4;
170 fh->fh_fsid_type = FSID_ENCODE_DEV;
171
172
173
174
175
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
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
209
210
211
212
213
214
215
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
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}
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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
327
328
329
330
331
332
333
334
335
336
337
338
339
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
355
356
357
358 if (access & NFSD_MAY_LOCK || access & NFSD_MAY_BYPASS_GSS)
359 goto skip_pseudoflavor_check;
360
361
362
363
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
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
392
393
394
395
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
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
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
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
487
488
489
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
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
522
523
524
525
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
539
540
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);
557 fhp->fh_export = exp_get(exp);
558
559 if (fhp->fh_handle.fh_version == 0xca) {
560
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
595
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
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
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
688
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}
696