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power_supply: Fix NULL pointer dereference during bq27x00_battery probe
[linux-2.6/btrfs-unstable.git] / fs / nfsd / nfs4acl.c
blob67242bf7c6cc3dfd5330f832f62a0043fec68480
1 /*
2 * Common NFSv4 ACL handling code.
3 *
4 * Copyright (c) 2002, 2003 The Regents of the University of Michigan.
5 * All rights reserved.
6 *
7 * Marius Aamodt Eriksen <marius@umich.edu>
8 * Jeff Sedlak <jsedlak@umich.edu>
9 * J. Bruce Fields <bfields@umich.edu>
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 *
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its
21 * contributors may be used to endorse or promote products derived
22 * from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
25 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
31 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
32 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
33 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 */
36
37 #include <linux/slab.h>
38 #include <linux/nfs_fs.h>
39 #include "nfsfh.h"
40 #include "nfsd.h"
41 #include "acl.h"
42 #include "vfs.h"
43
44 #define NFS4_ACL_TYPE_DEFAULT 0x01
45 #define NFS4_ACL_DIR 0x02
46 #define NFS4_ACL_OWNER 0x04
47
48 /* mode bit translations: */
49 #define NFS4_READ_MODE (NFS4_ACE_READ_DATA)
50 #define NFS4_WRITE_MODE (NFS4_ACE_WRITE_DATA | NFS4_ACE_APPEND_DATA)
51 #define NFS4_EXECUTE_MODE NFS4_ACE_EXECUTE
52 #define NFS4_ANYONE_MODE (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL | NFS4_ACE_SYNCHRONIZE)
53 #define NFS4_OWNER_MODE (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL)
54
55 /* We don't support these bits; insist they be neither allowed nor denied */
56 #define NFS4_MASK_UNSUPP (NFS4_ACE_DELETE | NFS4_ACE_WRITE_OWNER \
57 | NFS4_ACE_READ_NAMED_ATTRS | NFS4_ACE_WRITE_NAMED_ATTRS)
58
59 /* flags used to simulate posix default ACLs */
60 #define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \
61 | NFS4_ACE_DIRECTORY_INHERIT_ACE)
62
63 #define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS \
64 | NFS4_ACE_INHERIT_ONLY_ACE \
65 | NFS4_ACE_IDENTIFIER_GROUP)
66
67 #define MASK_EQUAL(mask1, mask2) \
68 ( ((mask1) & NFS4_ACE_MASK_ALL) == ((mask2) & NFS4_ACE_MASK_ALL) )
69
70 static u32
71 mask_from_posix(unsigned short perm, unsigned int flags)
72 {
73 int mask = NFS4_ANYONE_MODE;
74
75 if (flags & NFS4_ACL_OWNER)
76 mask |= NFS4_OWNER_MODE;
77 if (perm & ACL_READ)
78 mask |= NFS4_READ_MODE;
79 if (perm & ACL_WRITE)
80 mask |= NFS4_WRITE_MODE;
81 if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR))
82 mask |= NFS4_ACE_DELETE_CHILD;
83 if (perm & ACL_EXECUTE)
84 mask |= NFS4_EXECUTE_MODE;
85 return mask;
86 }
87
88 static u32
89 deny_mask_from_posix(unsigned short perm, u32 flags)
90 {
91 u32 mask = 0;
92
93 if (perm & ACL_READ)
94 mask |= NFS4_READ_MODE;
95 if (perm & ACL_WRITE)
96 mask |= NFS4_WRITE_MODE;
97 if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR))
98 mask |= NFS4_ACE_DELETE_CHILD;
99 if (perm & ACL_EXECUTE)
100 mask |= NFS4_EXECUTE_MODE;
101 return mask;
102 }
103
104 /* XXX: modify functions to return NFS errors; they're only ever
105 * used by nfs code, after all.... */
106
107 /* We only map from NFSv4 to POSIX ACLs when setting ACLs, when we err on the
108 * side of being more restrictive, so the mode bit mapping below is
109 * pessimistic. An optimistic version would be needed to handle DENY's,
110 * but we espect to coalesce all ALLOWs and DENYs before mapping to mode
111 * bits. */
112
113 static void
114 low_mode_from_nfs4(u32 perm, unsigned short *mode, unsigned int flags)
115 {
116 u32 write_mode = NFS4_WRITE_MODE;
117
118 if (flags & NFS4_ACL_DIR)
119 write_mode |= NFS4_ACE_DELETE_CHILD;
120 *mode = 0;
121 if ((perm & NFS4_READ_MODE) == NFS4_READ_MODE)
122 *mode |= ACL_READ;
123 if ((perm & write_mode) == write_mode)
124 *mode |= ACL_WRITE;
125 if ((perm & NFS4_EXECUTE_MODE) == NFS4_EXECUTE_MODE)
126 *mode |= ACL_EXECUTE;
127 }
128
129 struct ace_container {
130 struct nfs4_ace *ace;
131 struct list_head ace_l;
132 };
133
134 static short ace2type(struct nfs4_ace *);
135 static void _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *,
136 unsigned int);
137
138 int
139 nfsd4_get_nfs4_acl(struct svc_rqst *rqstp, struct dentry *dentry,
140 struct nfs4_acl **acl)
141 {
142 struct inode *inode = d_inode(dentry);
143 int error = 0;
144 struct posix_acl *pacl = NULL, *dpacl = NULL;
145 unsigned int flags = 0;
146 int size = 0;
147
148 pacl = get_acl(inode, ACL_TYPE_ACCESS);
149 if (!pacl)
150 pacl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
151
152 if (IS_ERR(pacl))
153 return PTR_ERR(pacl);
154
155 /* allocate for worst case: one (deny, allow) pair each: */
156 size += 2 * pacl->a_count;
157
158 if (S_ISDIR(inode->i_mode)) {
159 flags = NFS4_ACL_DIR;
160 dpacl = get_acl(inode, ACL_TYPE_DEFAULT);
161 if (IS_ERR(dpacl)) {
162 error = PTR_ERR(dpacl);
163 goto rel_pacl;
164 }
165
166 if (dpacl)
167 size += 2 * dpacl->a_count;
168 }
169
170 *acl = kmalloc(nfs4_acl_bytes(size), GFP_KERNEL);
171 if (*acl == NULL) {
172 error = -ENOMEM;
173 goto out;
174 }
175 (*acl)->naces = 0;
176
177 _posix_to_nfsv4_one(pacl, *acl, flags & ~NFS4_ACL_TYPE_DEFAULT);
178
179 if (dpacl)
180 _posix_to_nfsv4_one(dpacl, *acl, flags | NFS4_ACL_TYPE_DEFAULT);
181
182 out:
183 posix_acl_release(dpacl);
184 rel_pacl:
185 posix_acl_release(pacl);
186 return error;
187 }
188
189 struct posix_acl_summary {
190 unsigned short owner;
191 unsigned short users;
192 unsigned short group;
193 unsigned short groups;
194 unsigned short other;
195 unsigned short mask;
196 };
197
198 static void
199 summarize_posix_acl(struct posix_acl *acl, struct posix_acl_summary *pas)
200 {
201 struct posix_acl_entry *pa, *pe;
202
203 /*
204 * Only pas.users and pas.groups need initialization; previous
205 * posix_acl_valid() calls ensure that the other fields will be
206 * initialized in the following loop. But, just to placate gcc:
207 */
208 memset(pas, 0, sizeof(*pas));
209 pas->mask = 07;
210
211 pe = acl->a_entries + acl->a_count;
212
213 FOREACH_ACL_ENTRY(pa, acl, pe) {
214 switch (pa->e_tag) {
215 case ACL_USER_OBJ:
216 pas->owner = pa->e_perm;
217 break;
218 case ACL_GROUP_OBJ:
219 pas->group = pa->e_perm;
220 break;
221 case ACL_USER:
222 pas->users |= pa->e_perm;
223 break;
224 case ACL_GROUP:
225 pas->groups |= pa->e_perm;
226 break;
227 case ACL_OTHER:
228 pas->other = pa->e_perm;
229 break;
230 case ACL_MASK:
231 pas->mask = pa->e_perm;
232 break;
233 }
234 }
235 /* We'll only care about effective permissions: */
236 pas->users &= pas->mask;
237 pas->group &= pas->mask;
238 pas->groups &= pas->mask;
239 }
240
241 /* We assume the acl has been verified with posix_acl_valid. */
242 static void
243 _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl,
244 unsigned int flags)
245 {
246 struct posix_acl_entry *pa, *group_owner_entry;
247 struct nfs4_ace *ace;
248 struct posix_acl_summary pas;
249 unsigned short deny;
250 int eflag = ((flags & NFS4_ACL_TYPE_DEFAULT) ?
251 NFS4_INHERITANCE_FLAGS | NFS4_ACE_INHERIT_ONLY_ACE : 0);
252
253 BUG_ON(pacl->a_count < 3);
254 summarize_posix_acl(pacl, &pas);
255
256 pa = pacl->a_entries;
257 ace = acl->aces + acl->naces;
258
259 /* We could deny everything not granted by the owner: */
260 deny = ~pas.owner;
261 /*
262 * but it is equivalent (and simpler) to deny only what is not
263 * granted by later entries:
264 */
265 deny &= pas.users | pas.group | pas.groups | pas.other;
266 if (deny) {
267 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
268 ace->flag = eflag;
269 ace->access_mask = deny_mask_from_posix(deny, flags);
270 ace->whotype = NFS4_ACL_WHO_OWNER;
271 ace++;
272 acl->naces++;
273 }
274
275 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
276 ace->flag = eflag;
277 ace->access_mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER);
278 ace->whotype = NFS4_ACL_WHO_OWNER;
279 ace++;
280 acl->naces++;
281 pa++;
282
283 while (pa->e_tag == ACL_USER) {
284 deny = ~(pa->e_perm & pas.mask);
285 deny &= pas.groups | pas.group | pas.other;
286 if (deny) {
287 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
288 ace->flag = eflag;
289 ace->access_mask = deny_mask_from_posix(deny, flags);
290 ace->whotype = NFS4_ACL_WHO_NAMED;
291 ace->who_uid = pa->e_uid;
292 ace++;
293 acl->naces++;
294 }
295 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
296 ace->flag = eflag;
297 ace->access_mask = mask_from_posix(pa->e_perm & pas.mask,
298 flags);
299 ace->whotype = NFS4_ACL_WHO_NAMED;
300 ace->who_uid = pa->e_uid;
301 ace++;
302 acl->naces++;
303 pa++;
304 }
305
306 /* In the case of groups, we apply allow ACEs first, then deny ACEs,
307 * since a user can be in more than one group. */
308
309 /* allow ACEs */
310
311 group_owner_entry = pa;
312
313 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
314 ace->flag = eflag;
315 ace->access_mask = mask_from_posix(pas.group, flags);
316 ace->whotype = NFS4_ACL_WHO_GROUP;
317 ace++;
318 acl->naces++;
319 pa++;
320
321 while (pa->e_tag == ACL_GROUP) {
322 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
323 ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP;
324 ace->access_mask = mask_from_posix(pa->e_perm & pas.mask,
325 flags);
326 ace->whotype = NFS4_ACL_WHO_NAMED;
327 ace->who_gid = pa->e_gid;
328 ace++;
329 acl->naces++;
330 pa++;
331 }
332
333 /* deny ACEs */
334
335 pa = group_owner_entry;
336
337 deny = ~pas.group & pas.other;
338 if (deny) {
339 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
340 ace->flag = eflag;
341 ace->access_mask = deny_mask_from_posix(deny, flags);
342 ace->whotype = NFS4_ACL_WHO_GROUP;
343 ace++;
344 acl->naces++;
345 }
346 pa++;
347
348 while (pa->e_tag == ACL_GROUP) {
349 deny = ~(pa->e_perm & pas.mask);
350 deny &= pas.other;
351 if (deny) {
352 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
353 ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP;
354 ace->access_mask = deny_mask_from_posix(deny, flags);
355 ace->whotype = NFS4_ACL_WHO_NAMED;
356 ace->who_gid = pa->e_gid;
357 ace++;
358 acl->naces++;
359 }
360 pa++;
361 }
362
363 if (pa->e_tag == ACL_MASK)
364 pa++;
365 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
366 ace->flag = eflag;
367 ace->access_mask = mask_from_posix(pa->e_perm, flags);
368 ace->whotype = NFS4_ACL_WHO_EVERYONE;
369 acl->naces++;
370 }
371
372 static bool
373 pace_gt(struct posix_acl_entry *pace1, struct posix_acl_entry *pace2)
374 {
375 if (pace1->e_tag != pace2->e_tag)
376 return pace1->e_tag > pace2->e_tag;
377 if (pace1->e_tag == ACL_USER)
378 return uid_gt(pace1->e_uid, pace2->e_uid);
379 if (pace1->e_tag == ACL_GROUP)
380 return gid_gt(pace1->e_gid, pace2->e_gid);
381 return false;
382 }
383
384 static void
385 sort_pacl_range(struct posix_acl *pacl, int start, int end) {
386 int sorted = 0, i;
387 struct posix_acl_entry tmp;
388
389 /* We just do a bubble sort; easy to do in place, and we're not
390 * expecting acl's to be long enough to justify anything more. */
391 while (!sorted) {
392 sorted = 1;
393 for (i = start; i < end; i++) {
394 if (pace_gt(&pacl->a_entries[i],
395 &pacl->a_entries[i+1])) {
396 sorted = 0;
397 tmp = pacl->a_entries[i];
398 pacl->a_entries[i] = pacl->a_entries[i+1];
399 pacl->a_entries[i+1] = tmp;
400 }
401 }
402 }
403 }
404
405 static void
406 sort_pacl(struct posix_acl *pacl)
407 {
408 /* posix_acl_valid requires that users and groups be in order
409 * by uid/gid. */
410 int i, j;
411
412 /* no users or groups */
413 if (!pacl || pacl->a_count <= 4)
414 return;
415
416 i = 1;
417 while (pacl->a_entries[i].e_tag == ACL_USER)
418 i++;
419 sort_pacl_range(pacl, 1, i-1);
420
421 BUG_ON(pacl->a_entries[i].e_tag != ACL_GROUP_OBJ);
422 j = ++i;
423 while (pacl->a_entries[j].e_tag == ACL_GROUP)
424 j++;
425 sort_pacl_range(pacl, i, j-1);
426 return;
427 }
428
429 /*
430 * While processing the NFSv4 ACE, this maintains bitmasks representing
431 * which permission bits have been allowed and which denied to a given
432 * entity: */
433 struct posix_ace_state {
434 u32 allow;
435 u32 deny;
436 };
437
438 struct posix_user_ace_state {
439 union {
440 kuid_t uid;
441 kgid_t gid;
442 };
443 struct posix_ace_state perms;
444 };
445
446 struct posix_ace_state_array {
447 int n;
448 struct posix_user_ace_state aces[];
449 };
450
451 /*
452 * While processing the NFSv4 ACE, this maintains the partial permissions
453 * calculated so far: */
454
455 struct posix_acl_state {
456 int empty;
457 struct posix_ace_state owner;
458 struct posix_ace_state group;
459 struct posix_ace_state other;
460 struct posix_ace_state everyone;
461 struct posix_ace_state mask; /* Deny unused in this case */
462 struct posix_ace_state_array *users;
463 struct posix_ace_state_array *groups;
464 };
465
466 static int
467 init_state(struct posix_acl_state *state, int cnt)
468 {
469 int alloc;
470
471 memset(state, 0, sizeof(struct posix_acl_state));
472 state->empty = 1;
473 /*
474 * In the worst case, each individual acl could be for a distinct
475 * named user or group, but we don't no which, so we allocate
476 * enough space for either:
477 */
478 alloc = sizeof(struct posix_ace_state_array)
479 + cnt*sizeof(struct posix_user_ace_state);
480 state->users = kzalloc(alloc, GFP_KERNEL);
481 if (!state->users)
482 return -ENOMEM;
483 state->groups = kzalloc(alloc, GFP_KERNEL);
484 if (!state->groups) {
485 kfree(state->users);
486 return -ENOMEM;
487 }
488 return 0;
489 }
490
491 static void
492 free_state(struct posix_acl_state *state) {
493 kfree(state->users);
494 kfree(state->groups);
495 }
496
497 static inline void add_to_mask(struct posix_acl_state *state, struct posix_ace_state *astate)
498 {
499 state->mask.allow |= astate->allow;
500 }
501
502 static struct posix_acl *
503 posix_state_to_acl(struct posix_acl_state *state, unsigned int flags)
504 {
505 struct posix_acl_entry *pace;
506 struct posix_acl *pacl;
507 int nace;
508 int i;
509
510 /*
511 * ACLs with no ACEs are treated differently in the inheritable
512 * and effective cases: when there are no inheritable ACEs,
513 * calls ->set_acl with a NULL ACL structure.
514 */
515 if (state->empty && (flags & NFS4_ACL_TYPE_DEFAULT))
516 return NULL;
517
518 /*
519 * When there are no effective ACEs, the following will end
520 * up setting a 3-element effective posix ACL with all
521 * permissions zero.
522 */
523 if (!state->users->n && !state->groups->n)
524 nace = 3;
525 else /* Note we also include a MASK ACE in this case: */
526 nace = 4 + state->users->n + state->groups->n;
527 pacl = posix_acl_alloc(nace, GFP_KERNEL);
528 if (!pacl)
529 return ERR_PTR(-ENOMEM);
530
531 pace = pacl->a_entries;
532 pace->e_tag = ACL_USER_OBJ;
533 low_mode_from_nfs4(state->owner.allow, &pace->e_perm, flags);
534
535 for (i=0; i < state->users->n; i++) {
536 pace++;
537 pace->e_tag = ACL_USER;
538 low_mode_from_nfs4(state->users->aces[i].perms.allow,
539 &pace->e_perm, flags);
540 pace->e_uid = state->users->aces[i].uid;
541 add_to_mask(state, &state->users->aces[i].perms);
542 }
543
544 pace++;
545 pace->e_tag = ACL_GROUP_OBJ;
546 low_mode_from_nfs4(state->group.allow, &pace->e_perm, flags);
547 add_to_mask(state, &state->group);
548
549 for (i=0; i < state->groups->n; i++) {
550 pace++;
551 pace->e_tag = ACL_GROUP;
552 low_mode_from_nfs4(state->groups->aces[i].perms.allow,
553 &pace->e_perm, flags);
554 pace->e_gid = state->groups->aces[i].gid;
555 add_to_mask(state, &state->groups->aces[i].perms);
556 }
557
558 if (state->users->n || state->groups->n) {
559 pace++;
560 pace->e_tag = ACL_MASK;
561 low_mode_from_nfs4(state->mask.allow, &pace->e_perm, flags);
562 }
563
564 pace++;
565 pace->e_tag = ACL_OTHER;
566 low_mode_from_nfs4(state->other.allow, &pace->e_perm, flags);
567
568 return pacl;
569 }
570
571 static inline void allow_bits(struct posix_ace_state *astate, u32 mask)
572 {
573 /* Allow all bits in the mask not already denied: */
574 astate->allow |= mask & ~astate->deny;
575 }
576
577 static inline void deny_bits(struct posix_ace_state *astate, u32 mask)
578 {
579 /* Deny all bits in the mask not already allowed: */
580 astate->deny |= mask & ~astate->allow;
581 }
582
583 static int find_uid(struct posix_acl_state *state, kuid_t uid)
584 {
585 struct posix_ace_state_array *a = state->users;
586 int i;
587
588 for (i = 0; i < a->n; i++)
589 if (uid_eq(a->aces[i].uid, uid))
590 return i;
591 /* Not found: */
592 a->n++;
593 a->aces[i].uid = uid;
594 a->aces[i].perms.allow = state->everyone.allow;
595 a->aces[i].perms.deny = state->everyone.deny;
596
597 return i;
598 }
599
600 static int find_gid(struct posix_acl_state *state, kgid_t gid)
601 {
602 struct posix_ace_state_array *a = state->groups;
603 int i;
604
605 for (i = 0; i < a->n; i++)
606 if (gid_eq(a->aces[i].gid, gid))
607 return i;
608 /* Not found: */
609 a->n++;
610 a->aces[i].gid = gid;
611 a->aces[i].perms.allow = state->everyone.allow;
612 a->aces[i].perms.deny = state->everyone.deny;
613
614 return i;
615 }
616
617 static void deny_bits_array(struct posix_ace_state_array *a, u32 mask)
618 {
619 int i;
620
621 for (i=0; i < a->n; i++)
622 deny_bits(&a->aces[i].perms, mask);
623 }
624
625 static void allow_bits_array(struct posix_ace_state_array *a, u32 mask)
626 {
627 int i;
628
629 for (i=0; i < a->n; i++)
630 allow_bits(&a->aces[i].perms, mask);
631 }
632
633 static void process_one_v4_ace(struct posix_acl_state *state,
634 struct nfs4_ace *ace)
635 {
636 u32 mask = ace->access_mask;
637 int i;
638
639 state->empty = 0;
640
641 switch (ace2type(ace)) {
642 case ACL_USER_OBJ:
643 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
644 allow_bits(&state->owner, mask);
645 } else {
646 deny_bits(&state->owner, mask);
647 }
648 break;
649 case ACL_USER:
650 i = find_uid(state, ace->who_uid);
651 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
652 allow_bits(&state->users->aces[i].perms, mask);
653 } else {
654 deny_bits(&state->users->aces[i].perms, mask);
655 mask = state->users->aces[i].perms.deny;
656 deny_bits(&state->owner, mask);
657 }
658 break;
659 case ACL_GROUP_OBJ:
660 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
661 allow_bits(&state->group, mask);
662 } else {
663 deny_bits(&state->group, mask);
664 mask = state->group.deny;
665 deny_bits(&state->owner, mask);
666 deny_bits(&state->everyone, mask);
667 deny_bits_array(state->users, mask);
668 deny_bits_array(state->groups, mask);
669 }
670 break;
671 case ACL_GROUP:
672 i = find_gid(state, ace->who_gid);
673 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
674 allow_bits(&state->groups->aces[i].perms, mask);
675 } else {
676 deny_bits(&state->groups->aces[i].perms, mask);
677 mask = state->groups->aces[i].perms.deny;
678 deny_bits(&state->owner, mask);
679 deny_bits(&state->group, mask);
680 deny_bits(&state->everyone, mask);
681 deny_bits_array(state->users, mask);
682 deny_bits_array(state->groups, mask);
683 }
684 break;
685 case ACL_OTHER:
686 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
687 allow_bits(&state->owner, mask);
688 allow_bits(&state->group, mask);
689 allow_bits(&state->other, mask);
690 allow_bits(&state->everyone, mask);
691 allow_bits_array(state->users, mask);
692 allow_bits_array(state->groups, mask);
693 } else {
694 deny_bits(&state->owner, mask);
695 deny_bits(&state->group, mask);
696 deny_bits(&state->other, mask);
697 deny_bits(&state->everyone, mask);
698 deny_bits_array(state->users, mask);
699 deny_bits_array(state->groups, mask);
700 }
701 }
702 }
703
704 static int nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl,
705 struct posix_acl **pacl, struct posix_acl **dpacl,
706 unsigned int flags)
707 {
708 struct posix_acl_state effective_acl_state, default_acl_state;
709 struct nfs4_ace *ace;
710 int ret;
711
712 ret = init_state(&effective_acl_state, acl->naces);
713 if (ret)
714 return ret;
715 ret = init_state(&default_acl_state, acl->naces);
716 if (ret)
717 goto out_estate;
718 ret = -EINVAL;
719 for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
720 if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE &&
721 ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE)
722 goto out_dstate;
723 if (ace->flag & ~NFS4_SUPPORTED_FLAGS)
724 goto out_dstate;
725 if ((ace->flag & NFS4_INHERITANCE_FLAGS) == 0) {
726 process_one_v4_ace(&effective_acl_state, ace);
727 continue;
728 }
729 if (!(flags & NFS4_ACL_DIR))
730 goto out_dstate;
731 /*
732 * Note that when only one of FILE_INHERIT or DIRECTORY_INHERIT
733 * is set, we're effectively turning on the other. That's OK,
734 * according to rfc 3530.
735 */
736 process_one_v4_ace(&default_acl_state, ace);
737
738 if (!(ace->flag & NFS4_ACE_INHERIT_ONLY_ACE))
739 process_one_v4_ace(&effective_acl_state, ace);
740 }
741 *pacl = posix_state_to_acl(&effective_acl_state, flags);
742 if (IS_ERR(*pacl)) {
743 ret = PTR_ERR(*pacl);
744 *pacl = NULL;
745 goto out_dstate;
746 }
747 *dpacl = posix_state_to_acl(&default_acl_state,
748 flags | NFS4_ACL_TYPE_DEFAULT);
749 if (IS_ERR(*dpacl)) {
750 ret = PTR_ERR(*dpacl);
751 *dpacl = NULL;
752 posix_acl_release(*pacl);
753 *pacl = NULL;
754 goto out_dstate;
755 }
756 sort_pacl(*pacl);
757 sort_pacl(*dpacl);
758 ret = 0;
759 out_dstate:
760 free_state(&default_acl_state);
761 out_estate:
762 free_state(&effective_acl_state);
763 return ret;
764 }
765
766 __be32
767 nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
768 struct nfs4_acl *acl)
769 {
770 __be32 error;
771 int host_error;
772 struct dentry *dentry;
773 struct inode *inode;
774 struct posix_acl *pacl = NULL, *dpacl = NULL;
775 unsigned int flags = 0;
776
777 /* Get inode */
778 error = fh_verify(rqstp, fhp, 0, NFSD_MAY_SATTR);
779 if (error)
780 return error;
781
782 dentry = fhp->fh_dentry;
783 inode = d_inode(dentry);
784
785 if (!inode->i_op->set_acl || !IS_POSIXACL(inode))
786 return nfserr_attrnotsupp;
787
788 if (S_ISDIR(inode->i_mode))
789 flags = NFS4_ACL_DIR;
790
791 host_error = nfs4_acl_nfsv4_to_posix(acl, &pacl, &dpacl, flags);
792 if (host_error == -EINVAL)
793 return nfserr_attrnotsupp;
794 if (host_error < 0)
795 goto out_nfserr;
796
797 host_error = inode->i_op->set_acl(inode, pacl, ACL_TYPE_ACCESS);
798 if (host_error < 0)
799 goto out_release;
800
801 if (S_ISDIR(inode->i_mode)) {
802 host_error = inode->i_op->set_acl(inode, dpacl,
803 ACL_TYPE_DEFAULT);
804 }
805
806 out_release:
807 posix_acl_release(pacl);
808 posix_acl_release(dpacl);
809 out_nfserr:
810 if (host_error == -EOPNOTSUPP)
811 return nfserr_attrnotsupp;
812 else
813 return nfserrno(host_error);
814 }
815
816
817 static short
818 ace2type(struct nfs4_ace *ace)
819 {
820 switch (ace->whotype) {
821 case NFS4_ACL_WHO_NAMED:
822 return (ace->flag & NFS4_ACE_IDENTIFIER_GROUP ?
823 ACL_GROUP : ACL_USER);
824 case NFS4_ACL_WHO_OWNER:
825 return ACL_USER_OBJ;
826 case NFS4_ACL_WHO_GROUP:
827 return ACL_GROUP_OBJ;
828 case NFS4_ACL_WHO_EVERYONE:
829 return ACL_OTHER;
830 }
831 BUG();
832 return -1;
833 }
834
835 /*
836 * return the size of the struct nfs4_acl required to represent an acl
837 * with @entries entries.
838 */
839 int nfs4_acl_bytes(int entries)
840 {
841 return sizeof(struct nfs4_acl) + entries * sizeof(struct nfs4_ace);
842 }
843
844 static struct {
845 char *string;
846 int stringlen;
847 int type;
848 } s2t_map[] = {
849 {
850 .string = "OWNER@",
851 .stringlen = sizeof("OWNER@") - 1,
852 .type = NFS4_ACL_WHO_OWNER,
853 },
854 {
855 .string = "GROUP@",
856 .stringlen = sizeof("GROUP@") - 1,
857 .type = NFS4_ACL_WHO_GROUP,
858 },
859 {
860 .string = "EVERYONE@",
861 .stringlen = sizeof("EVERYONE@") - 1,
862 .type = NFS4_ACL_WHO_EVERYONE,
863 },
864 };
865
866 int
867 nfs4_acl_get_whotype(char *p, u32 len)
868 {
869 int i;
870
871 for (i = 0; i < ARRAY_SIZE(s2t_map); i++) {
872 if (s2t_map[i].stringlen == len &&
873 0 == memcmp(s2t_map[i].string, p, len))
874 return s2t_map[i].type;
875 }
876 return NFS4_ACL_WHO_NAMED;
877 }
878
879 __be32 nfs4_acl_write_who(struct xdr_stream *xdr, int who)
880 {
881 __be32 *p;
882 int i;
883
884 for (i = 0; i < ARRAY_SIZE(s2t_map); i++) {
885 if (s2t_map[i].type != who)
886 continue;
887 p = xdr_reserve_space(xdr, s2t_map[i].stringlen + 4);
888 if (!p)
889 return nfserr_resource;
890 p = xdr_encode_opaque(p, s2t_map[i].string,
891 s2t_map[i].stringlen);
892 return 0;
893 }
894 WARN_ON_ONCE(1);
895 return nfserr_serverfault;
896 }
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