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1da177e4 LT |
1 | /* |
2 | * fs/nfs4acl/acl.c | |
3 | * | |
4 | * Common NFSv4 ACL handling code. | |
5 | * | |
6 | * Copyright (c) 2002, 2003 The Regents of the University of Michigan. | |
7 | * All rights reserved. | |
8 | * | |
9 | * Marius Aamodt Eriksen <marius@umich.edu> | |
10 | * Jeff Sedlak <jsedlak@umich.edu> | |
11 | * J. Bruce Fields <bfields@umich.edu> | |
12 | * | |
13 | * Redistribution and use in source and binary forms, with or without | |
14 | * modification, are permitted provided that the following conditions | |
15 | * are met: | |
16 | * | |
17 | * 1. Redistributions of source code must retain the above copyright | |
18 | * notice, this list of conditions and the following disclaimer. | |
19 | * 2. Redistributions in binary form must reproduce the above copyright | |
20 | * notice, this list of conditions and the following disclaimer in the | |
21 | * documentation and/or other materials provided with the distribution. | |
22 | * 3. Neither the name of the University nor the names of its | |
23 | * contributors may be used to endorse or promote products derived | |
24 | * from this software without specific prior written permission. | |
25 | * | |
26 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED | |
27 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF | |
28 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE | |
29 | * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
30 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | |
31 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | |
32 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR | |
33 | * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF | |
34 | * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING | |
35 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS | |
36 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
37 | */ | |
38 | ||
39 | #include <linux/string.h> | |
40 | #include <linux/slab.h> | |
41 | #include <linux/list.h> | |
42 | #include <linux/types.h> | |
43 | #include <linux/fs.h> | |
44 | #include <linux/module.h> | |
45 | #include <linux/nfs_fs.h> | |
46 | #include <linux/posix_acl.h> | |
47 | #include <linux/nfs4.h> | |
48 | #include <linux/nfs4_acl.h> | |
49 | ||
50 | ||
51 | /* mode bit translations: */ | |
52 | #define NFS4_READ_MODE (NFS4_ACE_READ_DATA) | |
53 | #define NFS4_WRITE_MODE (NFS4_ACE_WRITE_DATA | NFS4_ACE_APPEND_DATA) | |
54 | #define NFS4_EXECUTE_MODE NFS4_ACE_EXECUTE | |
55 | #define NFS4_ANYONE_MODE (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL | NFS4_ACE_SYNCHRONIZE) | |
56 | #define NFS4_OWNER_MODE (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL) | |
57 | ||
58 | /* We don't support these bits; insist they be neither allowed nor denied */ | |
59 | #define NFS4_MASK_UNSUPP (NFS4_ACE_DELETE | NFS4_ACE_WRITE_OWNER \ | |
60 | | NFS4_ACE_READ_NAMED_ATTRS | NFS4_ACE_WRITE_NAMED_ATTRS) | |
61 | ||
62 | /* flags used to simulate posix default ACLs */ | |
63 | #define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \ | |
7bdfa68c | 64 | | NFS4_ACE_DIRECTORY_INHERIT_ACE) |
1da177e4 | 65 | |
7bdfa68c BF |
66 | #define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS \ |
67 | | NFS4_ACE_INHERIT_ONLY_ACE \ | |
68 | | NFS4_ACE_IDENTIFIER_GROUP) | |
b548edc2 | 69 | |
1da177e4 LT |
70 | #define MASK_EQUAL(mask1, mask2) \ |
71 | ( ((mask1) & NFS4_ACE_MASK_ALL) == ((mask2) & NFS4_ACE_MASK_ALL) ) | |
72 | ||
73 | static u32 | |
74 | mask_from_posix(unsigned short perm, unsigned int flags) | |
75 | { | |
76 | int mask = NFS4_ANYONE_MODE; | |
77 | ||
78 | if (flags & NFS4_ACL_OWNER) | |
79 | mask |= NFS4_OWNER_MODE; | |
80 | if (perm & ACL_READ) | |
81 | mask |= NFS4_READ_MODE; | |
82 | if (perm & ACL_WRITE) | |
83 | mask |= NFS4_WRITE_MODE; | |
84 | if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR)) | |
85 | mask |= NFS4_ACE_DELETE_CHILD; | |
86 | if (perm & ACL_EXECUTE) | |
87 | mask |= NFS4_EXECUTE_MODE; | |
88 | return mask; | |
89 | } | |
90 | ||
91 | static u32 | |
bec50c47 | 92 | deny_mask_from_posix(unsigned short perm, u32 flags) |
1da177e4 | 93 | { |
bec50c47 BF |
94 | u32 mask = 0; |
95 | ||
96 | if (perm & ACL_READ) | |
97 | mask |= NFS4_READ_MODE; | |
98 | if (perm & ACL_WRITE) | |
99 | mask |= NFS4_WRITE_MODE; | |
100 | if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR)) | |
101 | mask |= NFS4_ACE_DELETE_CHILD; | |
102 | if (perm & ACL_EXECUTE) | |
103 | mask |= NFS4_EXECUTE_MODE; | |
104 | return mask; | |
1da177e4 LT |
105 | } |
106 | ||
107 | /* XXX: modify functions to return NFS errors; they're only ever | |
108 | * used by nfs code, after all.... */ | |
109 | ||
09229edb BF |
110 | /* We only map from NFSv4 to POSIX ACLs when setting ACLs, when we err on the |
111 | * side of being more restrictive, so the mode bit mapping below is | |
112 | * pessimistic. An optimistic version would be needed to handle DENY's, | |
113 | * but we espect to coalesce all ALLOWs and DENYs before mapping to mode | |
114 | * bits. */ | |
115 | ||
116 | static void | |
117 | low_mode_from_nfs4(u32 perm, unsigned short *mode, unsigned int flags) | |
1da177e4 | 118 | { |
09229edb | 119 | u32 write_mode = NFS4_WRITE_MODE; |
1da177e4 | 120 | |
09229edb BF |
121 | if (flags & NFS4_ACL_DIR) |
122 | write_mode |= NFS4_ACE_DELETE_CHILD; | |
1da177e4 LT |
123 | *mode = 0; |
124 | if ((perm & NFS4_READ_MODE) == NFS4_READ_MODE) | |
125 | *mode |= ACL_READ; | |
09229edb | 126 | if ((perm & write_mode) == write_mode) |
1da177e4 LT |
127 | *mode |= ACL_WRITE; |
128 | if ((perm & NFS4_EXECUTE_MODE) == NFS4_EXECUTE_MODE) | |
129 | *mode |= ACL_EXECUTE; | |
1da177e4 LT |
130 | } |
131 | ||
132 | struct ace_container { | |
133 | struct nfs4_ace *ace; | |
134 | struct list_head ace_l; | |
135 | }; | |
136 | ||
137 | static short ace2type(struct nfs4_ace *); | |
28e05dd8 BF |
138 | static void _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *, |
139 | unsigned int); | |
1da177e4 LT |
140 | |
141 | struct nfs4_acl * | |
142 | nfs4_acl_posix_to_nfsv4(struct posix_acl *pacl, struct posix_acl *dpacl, | |
143 | unsigned int flags) | |
144 | { | |
145 | struct nfs4_acl *acl; | |
28e05dd8 | 146 | int size = 0; |
1da177e4 | 147 | |
28e05dd8 BF |
148 | if (pacl) { |
149 | if (posix_acl_valid(pacl) < 0) | |
150 | return ERR_PTR(-EINVAL); | |
151 | size += 2*pacl->a_count; | |
1da177e4 | 152 | } |
28e05dd8 BF |
153 | if (dpacl) { |
154 | if (posix_acl_valid(dpacl) < 0) | |
155 | return ERR_PTR(-EINVAL); | |
156 | size += 2*dpacl->a_count; | |
1da177e4 LT |
157 | } |
158 | ||
28e05dd8 BF |
159 | /* Allocate for worst case: one (deny, allow) pair each: */ |
160 | acl = nfs4_acl_new(size); | |
161 | if (acl == NULL) | |
162 | return ERR_PTR(-ENOMEM); | |
1da177e4 | 163 | |
28e05dd8 BF |
164 | if (pacl) |
165 | _posix_to_nfsv4_one(pacl, acl, flags & ~NFS4_ACL_TYPE_DEFAULT); | |
1da177e4 | 166 | |
28e05dd8 BF |
167 | if (dpacl) |
168 | _posix_to_nfsv4_one(dpacl, acl, flags | NFS4_ACL_TYPE_DEFAULT); | |
1da177e4 LT |
169 | |
170 | return acl; | |
171 | } | |
172 | ||
bec50c47 BF |
173 | struct posix_acl_summary { |
174 | unsigned short owner; | |
175 | unsigned short users; | |
176 | unsigned short group; | |
177 | unsigned short groups; | |
178 | unsigned short other; | |
179 | unsigned short mask; | |
180 | }; | |
181 | ||
28e05dd8 | 182 | static void |
bec50c47 | 183 | summarize_posix_acl(struct posix_acl *acl, struct posix_acl_summary *pas) |
1da177e4 | 184 | { |
bec50c47 | 185 | struct posix_acl_entry *pa, *pe; |
f7fede4b BF |
186 | |
187 | /* | |
188 | * Only pas.users and pas.groups need initialization; previous | |
189 | * posix_acl_valid() calls ensure that the other fields will be | |
190 | * initialized in the following loop. But, just to placate gcc: | |
191 | */ | |
192 | memset(pas, 0, sizeof(*pas)); | |
bec50c47 BF |
193 | pas->mask = 07; |
194 | ||
195 | pe = acl->a_entries + acl->a_count; | |
196 | ||
197 | FOREACH_ACL_ENTRY(pa, acl, pe) { | |
198 | switch (pa->e_tag) { | |
199 | case ACL_USER_OBJ: | |
200 | pas->owner = pa->e_perm; | |
201 | break; | |
202 | case ACL_GROUP_OBJ: | |
203 | pas->group = pa->e_perm; | |
204 | break; | |
205 | case ACL_USER: | |
206 | pas->users |= pa->e_perm; | |
207 | break; | |
208 | case ACL_GROUP: | |
209 | pas->groups |= pa->e_perm; | |
210 | break; | |
211 | case ACL_OTHER: | |
212 | pas->other = pa->e_perm; | |
213 | break; | |
214 | case ACL_MASK: | |
215 | pas->mask = pa->e_perm; | |
216 | break; | |
217 | } | |
218 | } | |
219 | /* We'll only care about effective permissions: */ | |
220 | pas->users &= pas->mask; | |
221 | pas->group &= pas->mask; | |
222 | pas->groups &= pas->mask; | |
1da177e4 LT |
223 | } |
224 | ||
225 | /* We assume the acl has been verified with posix_acl_valid. */ | |
28e05dd8 | 226 | static void |
1da177e4 LT |
227 | _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, |
228 | unsigned int flags) | |
229 | { | |
bec50c47 BF |
230 | struct posix_acl_entry *pa, *group_owner_entry; |
231 | struct nfs4_ace *ace; | |
232 | struct posix_acl_summary pas; | |
233 | unsigned short deny; | |
1da177e4 | 234 | int eflag = ((flags & NFS4_ACL_TYPE_DEFAULT) ? |
54c04409 | 235 | NFS4_INHERITANCE_FLAGS | NFS4_ACE_INHERIT_ONLY_ACE : 0); |
1da177e4 LT |
236 | |
237 | BUG_ON(pacl->a_count < 3); | |
bec50c47 | 238 | summarize_posix_acl(pacl, &pas); |
1da177e4 LT |
239 | |
240 | pa = pacl->a_entries; | |
bec50c47 BF |
241 | ace = acl->aces + acl->naces; |
242 | ||
243 | /* We could deny everything not granted by the owner: */ | |
244 | deny = ~pas.owner; | |
245 | /* | |
246 | * but it is equivalent (and simpler) to deny only what is not | |
247 | * granted by later entries: | |
248 | */ | |
249 | deny &= pas.users | pas.group | pas.groups | pas.other; | |
250 | if (deny) { | |
251 | ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; | |
252 | ace->flag = eflag; | |
253 | ace->access_mask = deny_mask_from_posix(deny, flags); | |
254 | ace->whotype = NFS4_ACL_WHO_OWNER; | |
255 | ace++; | |
256 | acl->naces++; | |
257 | } | |
258 | ||
259 | ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; | |
260 | ace->flag = eflag; | |
261 | ace->access_mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER); | |
262 | ace->whotype = NFS4_ACL_WHO_OWNER; | |
263 | ace++; | |
264 | acl->naces++; | |
1da177e4 LT |
265 | pa++; |
266 | ||
267 | while (pa->e_tag == ACL_USER) { | |
bec50c47 BF |
268 | deny = ~(pa->e_perm & pas.mask); |
269 | deny &= pas.groups | pas.group | pas.other; | |
270 | if (deny) { | |
271 | ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; | |
272 | ace->flag = eflag; | |
273 | ace->access_mask = deny_mask_from_posix(deny, flags); | |
274 | ace->whotype = NFS4_ACL_WHO_NAMED; | |
275 | ace->who = pa->e_id; | |
276 | ace++; | |
277 | acl->naces++; | |
278 | } | |
279 | ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; | |
280 | ace->flag = eflag; | |
281 | ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, | |
282 | flags); | |
283 | ace->whotype = NFS4_ACL_WHO_NAMED; | |
284 | ace->who = pa->e_id; | |
285 | ace++; | |
286 | acl->naces++; | |
1da177e4 LT |
287 | pa++; |
288 | } | |
289 | ||
290 | /* In the case of groups, we apply allow ACEs first, then deny ACEs, | |
291 | * since a user can be in more than one group. */ | |
292 | ||
293 | /* allow ACEs */ | |
294 | ||
1da177e4 | 295 | group_owner_entry = pa; |
bec50c47 BF |
296 | |
297 | ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; | |
298 | ace->flag = eflag; | |
299 | ace->access_mask = mask_from_posix(pas.group, flags); | |
300 | ace->whotype = NFS4_ACL_WHO_GROUP; | |
301 | ace++; | |
302 | acl->naces++; | |
1da177e4 LT |
303 | pa++; |
304 | ||
305 | while (pa->e_tag == ACL_GROUP) { | |
bec50c47 BF |
306 | ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; |
307 | ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; | |
308 | ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, | |
309 | flags); | |
310 | ace->whotype = NFS4_ACL_WHO_NAMED; | |
311 | ace->who = pa->e_id; | |
312 | ace++; | |
313 | acl->naces++; | |
1da177e4 LT |
314 | pa++; |
315 | } | |
316 | ||
317 | /* deny ACEs */ | |
318 | ||
319 | pa = group_owner_entry; | |
bec50c47 BF |
320 | |
321 | deny = ~pas.group & pas.other; | |
322 | if (deny) { | |
323 | ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; | |
324 | ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; | |
325 | ace->access_mask = deny_mask_from_posix(deny, flags); | |
326 | ace->whotype = NFS4_ACL_WHO_GROUP; | |
327 | ace++; | |
328 | acl->naces++; | |
329 | } | |
1da177e4 | 330 | pa++; |
bec50c47 | 331 | |
1da177e4 | 332 | while (pa->e_tag == ACL_GROUP) { |
bec50c47 BF |
333 | deny = ~(pa->e_perm & pas.mask); |
334 | deny &= pas.other; | |
335 | if (deny) { | |
336 | ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; | |
337 | ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; | |
338 | ace->access_mask = mask_from_posix(deny, flags); | |
339 | ace->whotype = NFS4_ACL_WHO_NAMED; | |
340 | ace->who = pa->e_id; | |
341 | ace++; | |
342 | acl->naces++; | |
343 | } | |
1da177e4 LT |
344 | pa++; |
345 | } | |
346 | ||
347 | if (pa->e_tag == ACL_MASK) | |
348 | pa++; | |
bec50c47 BF |
349 | ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; |
350 | ace->flag = eflag; | |
351 | ace->access_mask = mask_from_posix(pa->e_perm, flags); | |
352 | ace->whotype = NFS4_ACL_WHO_EVERYONE; | |
353 | acl->naces++; | |
1da177e4 LT |
354 | } |
355 | ||
356 | static void | |
357 | sort_pacl_range(struct posix_acl *pacl, int start, int end) { | |
358 | int sorted = 0, i; | |
359 | struct posix_acl_entry tmp; | |
360 | ||
361 | /* We just do a bubble sort; easy to do in place, and we're not | |
362 | * expecting acl's to be long enough to justify anything more. */ | |
363 | while (!sorted) { | |
364 | sorted = 1; | |
365 | for (i = start; i < end; i++) { | |
366 | if (pacl->a_entries[i].e_id | |
367 | > pacl->a_entries[i+1].e_id) { | |
368 | sorted = 0; | |
369 | tmp = pacl->a_entries[i]; | |
370 | pacl->a_entries[i] = pacl->a_entries[i+1]; | |
371 | pacl->a_entries[i+1] = tmp; | |
372 | } | |
373 | } | |
374 | } | |
375 | } | |
376 | ||
377 | static void | |
378 | sort_pacl(struct posix_acl *pacl) | |
379 | { | |
380 | /* posix_acl_valid requires that users and groups be in order | |
381 | * by uid/gid. */ | |
382 | int i, j; | |
383 | ||
384 | if (pacl->a_count <= 4) | |
385 | return; /* no users or groups */ | |
386 | i = 1; | |
387 | while (pacl->a_entries[i].e_tag == ACL_USER) | |
388 | i++; | |
389 | sort_pacl_range(pacl, 1, i-1); | |
390 | ||
391 | BUG_ON(pacl->a_entries[i].e_tag != ACL_GROUP_OBJ); | |
392 | j = i++; | |
393 | while (pacl->a_entries[j].e_tag == ACL_GROUP) | |
394 | j++; | |
395 | sort_pacl_range(pacl, i, j-1); | |
396 | return; | |
397 | } | |
398 | ||
09229edb BF |
399 | /* |
400 | * While processing the NFSv4 ACE, this maintains bitmasks representing | |
401 | * which permission bits have been allowed and which denied to a given | |
402 | * entity: */ | |
403 | struct posix_ace_state { | |
404 | u32 allow; | |
405 | u32 deny; | |
406 | }; | |
407 | ||
408 | struct posix_user_ace_state { | |
409 | uid_t uid; | |
410 | struct posix_ace_state perms; | |
411 | }; | |
412 | ||
413 | struct posix_ace_state_array { | |
414 | int n; | |
415 | struct posix_user_ace_state aces[]; | |
416 | }; | |
417 | ||
418 | /* | |
419 | * While processing the NFSv4 ACE, this maintains the partial permissions | |
420 | * calculated so far: */ | |
421 | ||
422 | struct posix_acl_state { | |
3160a711 | 423 | int empty; |
09229edb BF |
424 | struct posix_ace_state owner; |
425 | struct posix_ace_state group; | |
426 | struct posix_ace_state other; | |
427 | struct posix_ace_state everyone; | |
428 | struct posix_ace_state mask; /* Deny unused in this case */ | |
429 | struct posix_ace_state_array *users; | |
430 | struct posix_ace_state_array *groups; | |
431 | }; | |
432 | ||
1da177e4 | 433 | static int |
09229edb | 434 | init_state(struct posix_acl_state *state, int cnt) |
1da177e4 | 435 | { |
09229edb BF |
436 | int alloc; |
437 | ||
438 | memset(state, 0, sizeof(struct posix_acl_state)); | |
3160a711 | 439 | state->empty = 1; |
09229edb BF |
440 | /* |
441 | * In the worst case, each individual acl could be for a distinct | |
442 | * named user or group, but we don't no which, so we allocate | |
443 | * enough space for either: | |
444 | */ | |
445 | alloc = sizeof(struct posix_ace_state_array) | |
446 | + cnt*sizeof(struct posix_ace_state); | |
447 | state->users = kzalloc(alloc, GFP_KERNEL); | |
448 | if (!state->users) | |
449 | return -ENOMEM; | |
450 | state->groups = kzalloc(alloc, GFP_KERNEL); | |
451 | if (!state->groups) { | |
452 | kfree(state->users); | |
453 | return -ENOMEM; | |
454 | } | |
455 | return 0; | |
1da177e4 LT |
456 | } |
457 | ||
09229edb BF |
458 | static void |
459 | free_state(struct posix_acl_state *state) { | |
460 | kfree(state->users); | |
461 | kfree(state->groups); | |
1da177e4 LT |
462 | } |
463 | ||
09229edb | 464 | static inline void add_to_mask(struct posix_acl_state *state, struct posix_ace_state *astate) |
1da177e4 | 465 | { |
09229edb | 466 | state->mask.allow |= astate->allow; |
1da177e4 LT |
467 | } |
468 | ||
09229edb BF |
469 | /* |
470 | * Certain bits (SYNCHRONIZE, DELETE, WRITE_OWNER, READ/WRITE_NAMED_ATTRS, | |
471 | * READ_ATTRIBUTES, READ_ACL) are currently unenforceable and don't translate | |
472 | * to traditional read/write/execute permissions. | |
473 | * | |
474 | * It's problematic to reject acls that use certain mode bits, because it | |
475 | * places the burden on users to learn the rules about which bits one | |
476 | * particular server sets, without giving the user a lot of help--we return an | |
477 | * error that could mean any number of different things. To make matters | |
478 | * worse, the problematic bits might be introduced by some application that's | |
479 | * automatically mapping from some other acl model. | |
480 | * | |
481 | * So wherever possible we accept anything, possibly erring on the side of | |
482 | * denying more permissions than necessary. | |
483 | * | |
484 | * However we do reject *explicit* DENY's of a few bits representing | |
485 | * permissions we could never deny: | |
486 | */ | |
1da177e4 | 487 | |
09229edb BF |
488 | static inline int check_deny(u32 mask, int isowner) |
489 | { | |
490 | if (mask & (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL)) | |
491 | return -EINVAL; | |
492 | if (!isowner) | |
493 | return 0; | |
494 | if (mask & (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL)) | |
495 | return -EINVAL; | |
496 | return 0; | |
1da177e4 LT |
497 | } |
498 | ||
09229edb BF |
499 | static struct posix_acl * |
500 | posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) | |
1da177e4 | 501 | { |
09229edb BF |
502 | struct posix_acl_entry *pace; |
503 | struct posix_acl *pacl; | |
504 | int nace; | |
505 | int i, error = 0; | |
1da177e4 | 506 | |
3160a711 BF |
507 | /* |
508 | * ACLs with no ACEs are treated differently in the inheritable | |
509 | * and effective cases: when there are no inheritable ACEs, we | |
510 | * set a zero-length default posix acl: | |
511 | */ | |
512 | if (state->empty && (flags & NFS4_ACL_TYPE_DEFAULT)) { | |
513 | pacl = posix_acl_alloc(0, GFP_KERNEL); | |
514 | return pacl ? pacl : ERR_PTR(-ENOMEM); | |
515 | } | |
516 | /* | |
517 | * When there are no effective ACEs, the following will end | |
518 | * up setting a 3-element effective posix ACL with all | |
519 | * permissions zero. | |
520 | */ | |
09229edb BF |
521 | nace = 4 + state->users->n + state->groups->n; |
522 | pacl = posix_acl_alloc(nace, GFP_KERNEL); | |
523 | if (!pacl) | |
524 | return ERR_PTR(-ENOMEM); | |
1da177e4 | 525 | |
09229edb BF |
526 | pace = pacl->a_entries; |
527 | pace->e_tag = ACL_USER_OBJ; | |
528 | error = check_deny(state->owner.deny, 1); | |
529 | if (error) | |
530 | goto out_err; | |
531 | low_mode_from_nfs4(state->owner.allow, &pace->e_perm, flags); | |
532 | pace->e_id = ACL_UNDEFINED_ID; | |
533 | ||
534 | for (i=0; i < state->users->n; i++) { | |
535 | pace++; | |
536 | pace->e_tag = ACL_USER; | |
537 | error = check_deny(state->users->aces[i].perms.deny, 0); | |
538 | if (error) | |
539 | goto out_err; | |
540 | low_mode_from_nfs4(state->users->aces[i].perms.allow, | |
541 | &pace->e_perm, flags); | |
542 | pace->e_id = state->users->aces[i].uid; | |
543 | add_to_mask(state, &state->users->aces[i].perms); | |
1da177e4 LT |
544 | } |
545 | ||
09229edb BF |
546 | pace++; |
547 | pace->e_tag = ACL_GROUP_OBJ; | |
548 | error = check_deny(state->group.deny, 0); | |
549 | if (error) | |
550 | goto out_err; | |
551 | low_mode_from_nfs4(state->group.allow, &pace->e_perm, flags); | |
552 | pace->e_id = ACL_UNDEFINED_ID; | |
553 | add_to_mask(state, &state->group); | |
554 | ||
555 | for (i=0; i < state->groups->n; i++) { | |
556 | pace++; | |
557 | pace->e_tag = ACL_GROUP; | |
558 | error = check_deny(state->groups->aces[i].perms.deny, 0); | |
559 | if (error) | |
560 | goto out_err; | |
561 | low_mode_from_nfs4(state->groups->aces[i].perms.allow, | |
562 | &pace->e_perm, flags); | |
563 | pace->e_id = state->groups->aces[i].uid; | |
564 | add_to_mask(state, &state->groups->aces[i].perms); | |
565 | } | |
1da177e4 | 566 | |
09229edb BF |
567 | pace++; |
568 | pace->e_tag = ACL_MASK; | |
569 | low_mode_from_nfs4(state->mask.allow, &pace->e_perm, flags); | |
570 | pace->e_id = ACL_UNDEFINED_ID; | |
1da177e4 | 571 | |
09229edb BF |
572 | pace++; |
573 | pace->e_tag = ACL_OTHER; | |
574 | error = check_deny(state->other.deny, 0); | |
575 | if (error) | |
576 | goto out_err; | |
577 | low_mode_from_nfs4(state->other.allow, &pace->e_perm, flags); | |
578 | pace->e_id = ACL_UNDEFINED_ID; | |
1da177e4 | 579 | |
09229edb BF |
580 | return pacl; |
581 | out_err: | |
582 | posix_acl_release(pacl); | |
583 | return ERR_PTR(error); | |
584 | } | |
1da177e4 | 585 | |
09229edb BF |
586 | static inline void allow_bits(struct posix_ace_state *astate, u32 mask) |
587 | { | |
588 | /* Allow all bits in the mask not already denied: */ | |
589 | astate->allow |= mask & ~astate->deny; | |
590 | } | |
1da177e4 | 591 | |
09229edb BF |
592 | static inline void deny_bits(struct posix_ace_state *astate, u32 mask) |
593 | { | |
594 | /* Deny all bits in the mask not already allowed: */ | |
595 | astate->deny |= mask & ~astate->allow; | |
596 | } | |
1da177e4 | 597 | |
09229edb BF |
598 | static int find_uid(struct posix_acl_state *state, struct posix_ace_state_array *a, uid_t uid) |
599 | { | |
600 | int i; | |
1da177e4 | 601 | |
09229edb BF |
602 | for (i = 0; i < a->n; i++) |
603 | if (a->aces[i].uid == uid) | |
604 | return i; | |
605 | /* Not found: */ | |
606 | a->n++; | |
607 | a->aces[i].uid = uid; | |
608 | a->aces[i].perms.allow = state->everyone.allow; | |
609 | a->aces[i].perms.deny = state->everyone.deny; | |
1da177e4 | 610 | |
09229edb | 611 | return i; |
1da177e4 LT |
612 | } |
613 | ||
09229edb | 614 | static void deny_bits_array(struct posix_ace_state_array *a, u32 mask) |
1da177e4 | 615 | { |
09229edb | 616 | int i; |
1da177e4 | 617 | |
09229edb BF |
618 | for (i=0; i < a->n; i++) |
619 | deny_bits(&a->aces[i].perms, mask); | |
1da177e4 LT |
620 | } |
621 | ||
09229edb | 622 | static void allow_bits_array(struct posix_ace_state_array *a, u32 mask) |
1da177e4 | 623 | { |
09229edb | 624 | int i; |
1da177e4 | 625 | |
09229edb BF |
626 | for (i=0; i < a->n; i++) |
627 | allow_bits(&a->aces[i].perms, mask); | |
1da177e4 LT |
628 | } |
629 | ||
09229edb BF |
630 | static void process_one_v4_ace(struct posix_acl_state *state, |
631 | struct nfs4_ace *ace) | |
1da177e4 | 632 | { |
09229edb BF |
633 | u32 mask = ace->access_mask; |
634 | int i; | |
635 | ||
3160a711 BF |
636 | state->empty = 0; |
637 | ||
09229edb BF |
638 | switch (ace2type(ace)) { |
639 | case ACL_USER_OBJ: | |
640 | if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { | |
641 | allow_bits(&state->owner, mask); | |
642 | } else { | |
643 | deny_bits(&state->owner, mask); | |
644 | } | |
645 | break; | |
646 | case ACL_USER: | |
647 | i = find_uid(state, state->users, ace->who); | |
648 | if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { | |
649 | allow_bits(&state->users->aces[i].perms, mask); | |
650 | } else { | |
651 | deny_bits(&state->users->aces[i].perms, mask); | |
652 | mask = state->users->aces[i].perms.deny; | |
653 | deny_bits(&state->owner, mask); | |
654 | } | |
655 | break; | |
656 | case ACL_GROUP_OBJ: | |
657 | if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { | |
658 | allow_bits(&state->group, mask); | |
659 | } else { | |
660 | deny_bits(&state->group, mask); | |
661 | mask = state->group.deny; | |
662 | deny_bits(&state->owner, mask); | |
663 | deny_bits(&state->everyone, mask); | |
664 | deny_bits_array(state->users, mask); | |
665 | deny_bits_array(state->groups, mask); | |
666 | } | |
667 | break; | |
668 | case ACL_GROUP: | |
669 | i = find_uid(state, state->groups, ace->who); | |
670 | if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { | |
671 | allow_bits(&state->groups->aces[i].perms, mask); | |
672 | } else { | |
673 | deny_bits(&state->groups->aces[i].perms, mask); | |
674 | mask = state->groups->aces[i].perms.deny; | |
675 | deny_bits(&state->owner, mask); | |
676 | deny_bits(&state->group, mask); | |
677 | deny_bits(&state->everyone, mask); | |
678 | deny_bits_array(state->users, mask); | |
679 | deny_bits_array(state->groups, mask); | |
680 | } | |
681 | break; | |
682 | case ACL_OTHER: | |
683 | if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { | |
684 | allow_bits(&state->owner, mask); | |
685 | allow_bits(&state->group, mask); | |
686 | allow_bits(&state->other, mask); | |
687 | allow_bits(&state->everyone, mask); | |
688 | allow_bits_array(state->users, mask); | |
689 | allow_bits_array(state->groups, mask); | |
690 | } else { | |
691 | deny_bits(&state->owner, mask); | |
692 | deny_bits(&state->group, mask); | |
693 | deny_bits(&state->other, mask); | |
694 | deny_bits(&state->everyone, mask); | |
695 | deny_bits_array(state->users, mask); | |
696 | deny_bits_array(state->groups, mask); | |
697 | } | |
1da177e4 LT |
698 | } |
699 | } | |
700 | ||
575a6290 BF |
701 | int nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl, struct posix_acl **pacl, |
702 | struct posix_acl **dpacl, unsigned int flags) | |
1da177e4 | 703 | { |
575a6290 | 704 | struct posix_acl_state effective_acl_state, default_acl_state; |
09229edb BF |
705 | struct nfs4_ace *ace; |
706 | int ret; | |
1da177e4 | 707 | |
575a6290 | 708 | ret = init_state(&effective_acl_state, acl->naces); |
09229edb | 709 | if (ret) |
575a6290 BF |
710 | return ret; |
711 | ret = init_state(&default_acl_state, acl->naces); | |
712 | if (ret) | |
713 | goto out_estate; | |
714 | ret = -EINVAL; | |
28e05dd8 | 715 | for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) { |
09229edb BF |
716 | if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE && |
717 | ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE) | |
575a6290 | 718 | goto out_dstate; |
b548edc2 | 719 | if (ace->flag & ~NFS4_SUPPORTED_FLAGS) |
575a6290 | 720 | goto out_dstate; |
7bdfa68c | 721 | if ((ace->flag & NFS4_INHERITANCE_FLAGS) == 0) { |
575a6290 | 722 | process_one_v4_ace(&effective_acl_state, ace); |
b548edc2 | 723 | continue; |
7bdfa68c | 724 | } |
575a6290 BF |
725 | if (!(flags & NFS4_ACL_DIR)) |
726 | goto out_dstate; | |
7bdfa68c BF |
727 | /* |
728 | * Note that when only one of FILE_INHERIT or DIRECTORY_INHERIT | |
729 | * is set, we're effectively turning on the other. That's OK, | |
730 | * according to rfc 3530. | |
731 | */ | |
575a6290 BF |
732 | process_one_v4_ace(&default_acl_state, ace); |
733 | ||
734 | if (!(ace->flag & NFS4_ACE_INHERIT_ONLY_ACE)) | |
735 | process_one_v4_ace(&effective_acl_state, ace); | |
1da177e4 | 736 | } |
575a6290 BF |
737 | *pacl = posix_state_to_acl(&effective_acl_state, flags); |
738 | if (IS_ERR(*pacl)) { | |
739 | ret = PTR_ERR(*pacl); | |
4b2ca38a | 740 | *pacl = NULL; |
575a6290 BF |
741 | goto out_dstate; |
742 | } | |
3160a711 BF |
743 | *dpacl = posix_state_to_acl(&default_acl_state, |
744 | flags | NFS4_ACL_TYPE_DEFAULT); | |
575a6290 BF |
745 | if (IS_ERR(*dpacl)) { |
746 | ret = PTR_ERR(*dpacl); | |
4b2ca38a | 747 | *dpacl = NULL; |
575a6290 | 748 | posix_acl_release(*pacl); |
4b2ca38a | 749 | *pacl = NULL; |
575a6290 BF |
750 | goto out_dstate; |
751 | } | |
752 | sort_pacl(*pacl); | |
753 | sort_pacl(*dpacl); | |
754 | ret = 0; | |
755 | out_dstate: | |
756 | free_state(&default_acl_state); | |
757 | out_estate: | |
758 | free_state(&effective_acl_state); | |
759 | return ret; | |
1da177e4 LT |
760 | } |
761 | ||
762 | static short | |
763 | ace2type(struct nfs4_ace *ace) | |
764 | { | |
765 | switch (ace->whotype) { | |
766 | case NFS4_ACL_WHO_NAMED: | |
767 | return (ace->flag & NFS4_ACE_IDENTIFIER_GROUP ? | |
768 | ACL_GROUP : ACL_USER); | |
769 | case NFS4_ACL_WHO_OWNER: | |
770 | return ACL_USER_OBJ; | |
771 | case NFS4_ACL_WHO_GROUP: | |
772 | return ACL_GROUP_OBJ; | |
773 | case NFS4_ACL_WHO_EVERYONE: | |
774 | return ACL_OTHER; | |
775 | } | |
776 | BUG(); | |
777 | return -1; | |
778 | } | |
779 | ||
780 | EXPORT_SYMBOL(nfs4_acl_posix_to_nfsv4); | |
781 | EXPORT_SYMBOL(nfs4_acl_nfsv4_to_posix); | |
782 | ||
783 | struct nfs4_acl * | |
28e05dd8 | 784 | nfs4_acl_new(int n) |
1da177e4 LT |
785 | { |
786 | struct nfs4_acl *acl; | |
787 | ||
28e05dd8 BF |
788 | acl = kmalloc(sizeof(*acl) + n*sizeof(struct nfs4_ace), GFP_KERNEL); |
789 | if (acl == NULL) | |
1da177e4 | 790 | return NULL; |
1da177e4 | 791 | acl->naces = 0; |
1da177e4 LT |
792 | return acl; |
793 | } | |
794 | ||
1da177e4 LT |
795 | static struct { |
796 | char *string; | |
797 | int stringlen; | |
798 | int type; | |
799 | } s2t_map[] = { | |
800 | { | |
801 | .string = "OWNER@", | |
802 | .stringlen = sizeof("OWNER@") - 1, | |
803 | .type = NFS4_ACL_WHO_OWNER, | |
804 | }, | |
805 | { | |
806 | .string = "GROUP@", | |
807 | .stringlen = sizeof("GROUP@") - 1, | |
808 | .type = NFS4_ACL_WHO_GROUP, | |
809 | }, | |
810 | { | |
811 | .string = "EVERYONE@", | |
812 | .stringlen = sizeof("EVERYONE@") - 1, | |
813 | .type = NFS4_ACL_WHO_EVERYONE, | |
814 | }, | |
815 | }; | |
816 | ||
817 | int | |
818 | nfs4_acl_get_whotype(char *p, u32 len) | |
819 | { | |
820 | int i; | |
821 | ||
e8c96f8c | 822 | for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { |
1da177e4 LT |
823 | if (s2t_map[i].stringlen == len && |
824 | 0 == memcmp(s2t_map[i].string, p, len)) | |
825 | return s2t_map[i].type; | |
826 | } | |
827 | return NFS4_ACL_WHO_NAMED; | |
828 | } | |
829 | ||
830 | int | |
831 | nfs4_acl_write_who(int who, char *p) | |
832 | { | |
833 | int i; | |
834 | ||
e8c96f8c | 835 | for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { |
1da177e4 LT |
836 | if (s2t_map[i].type == who) { |
837 | memcpy(p, s2t_map[i].string, s2t_map[i].stringlen); | |
838 | return s2t_map[i].stringlen; | |
839 | } | |
840 | } | |
841 | BUG(); | |
842 | return -1; | |
843 | } | |
844 | ||
1da177e4 | 845 | EXPORT_SYMBOL(nfs4_acl_new); |
1da177e4 LT |
846 | EXPORT_SYMBOL(nfs4_acl_get_whotype); |
847 | EXPORT_SYMBOL(nfs4_acl_write_who); |