1 /*-
2 * Copyright (c) 2008-2009 Edward Tomasz NapieraĆa <trasz@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 /*
28 * ACL support routines specific to NFSv4 access control lists. These are
29 * utility routines for code common across file systems implementing NFSv4
30 * ACLs.
31 */
32
33 #ifdef _KERNEL
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/mount.h>
40 #include <sys/priv.h>
41 #include <sys/vnode.h>
42 #include <sys/errno.h>
43 #include <sys/stat.h>
44 #include <sys/acl.h>
45 #else
46 #include <errno.h>
47 #include <assert.h>
48 #include <sys/acl.h>
49 #include <sys/stat.h>
50 #define KASSERT(a, b) assert(a)
51 #define CTASSERT(a)
52 #endif /* _KERNEL */
53
54 #ifdef _KERNEL
55
56 static struct {
57 accmode_t accmode;
58 int mask;
59 } accmode2mask[] = {{VREAD, ACL_READ_DATA},
60 {VWRITE, ACL_WRITE_DATA},
61 {VAPPEND, ACL_APPEND_DATA},
62 {VEXEC, ACL_EXECUTE},
63 {VREAD_NAMED_ATTRS, ACL_READ_NAMED_ATTRS},
64 {VWRITE_NAMED_ATTRS, ACL_WRITE_NAMED_ATTRS},
65 {VDELETE_CHILD, ACL_DELETE_CHILD},
66 {VREAD_ATTRIBUTES, ACL_READ_ATTRIBUTES},
67 {VWRITE_ATTRIBUTES, ACL_WRITE_ATTRIBUTES},
68 {VDELETE, ACL_DELETE},
69 {VREAD_ACL, ACL_READ_ACL},
70 {VWRITE_ACL, ACL_WRITE_ACL},
71 {VWRITE_OWNER, ACL_WRITE_OWNER},
72 {VSYNCHRONIZE, ACL_SYNCHRONIZE},
73 {0, 0}};
74
75 static int
76 _access_mask_from_accmode(accmode_t accmode)
77 {
78 int access_mask = 0, i;
79
80 for (i = 0; accmode2mask[i].accmode != 0; i++) {
81 if (accmode & accmode2mask[i].accmode)
82 access_mask |= accmode2mask[i].mask;
83 }
84
85 /*
86 * VAPPEND is just a modifier for VWRITE; if the caller asked
87 * for 'VAPPEND | VWRITE', we want to check for ACL_APPEND_DATA only.
88 */
89 if (access_mask & ACL_APPEND_DATA)
90 access_mask &= ~ACL_WRITE_DATA;
91
92 return (access_mask);
93 }
94
95 /*
96 * Return 0, iff access is allowed, 1 otherwise.
97 */
98 static int
99 _acl_denies(const struct acl *aclp, int access_mask, struct ucred *cred,
100 int file_uid, int file_gid, int *denied_explicitly)
101 {
102 int i;
103 const struct acl_entry *entry;
104
105 if (denied_explicitly != NULL)
106 *denied_explicitly = 0;
107
108 KASSERT(aclp->acl_cnt <= ACL_MAX_ENTRIES,
109 ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
110
111 for (i = 0; i < aclp->acl_cnt; i++) {
112 entry = &(aclp->acl_entry[i]);
113
114 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
115 entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
116 continue;
117 if (entry->ae_flags & ACL_ENTRY_INHERIT_ONLY)
118 continue;
119 switch (entry->ae_tag) {
120 case ACL_USER_OBJ:
121 if (file_uid != cred->cr_uid)
122 continue;
123 break;
124 case ACL_USER:
125 if (entry->ae_id != cred->cr_uid)
126 continue;
127 break;
128 case ACL_GROUP_OBJ:
129 if (!groupmember(file_gid, cred))
130 continue;
131 break;
132 case ACL_GROUP:
133 if (!groupmember(entry->ae_id, cred))
134 continue;
135 break;
136 default:
137 KASSERT(entry->ae_tag == ACL_EVERYONE,
138 ("entry->ae_tag == ACL_EVERYONE"));
139 }
140
141 if (entry->ae_entry_type == ACL_ENTRY_TYPE_DENY) {
142 if (entry->ae_perm & access_mask) {
143 if (denied_explicitly != NULL)
144 *denied_explicitly = 1;
145 return (1);
146 }
147 }
148
149 access_mask &= ~(entry->ae_perm);
150 if (access_mask == 0)
151 return (0);
152 }
153
154 return (1);
155 }
156
157 int
158 vaccess_acl_nfs4(enum vtype type, uid_t file_uid, gid_t file_gid,
159 struct acl *aclp, accmode_t accmode, struct ucred *cred, int *privused)
160 {
161 accmode_t priv_granted = 0;
162 int denied, explicitly_denied, access_mask, is_directory,
163 must_be_owner = 0;
164
165 if (privused != NULL)
166 *privused = 0;
167
168 if (accmode & VADMIN)
169 must_be_owner = 1;
170
171 /*
172 * Ignore VSYNCHRONIZE permission.
173 */
174 accmode &= ~VSYNCHRONIZE;
175
176 access_mask = _access_mask_from_accmode(accmode);
177
178 if (type == VDIR)
179 is_directory = 1;
180 else
181 is_directory = 0;
182
183 /*
184 * File owner is always allowed to read and write the ACL
185 * and basic attributes. This is to prevent a situation
186 * where user would change ACL in a way that prevents him
187 * from undoing the change.
188 */
189 if (file_uid == cred->cr_uid)
190 access_mask &= ~(ACL_READ_ACL | ACL_WRITE_ACL |
191 ACL_READ_ATTRIBUTES | ACL_WRITE_ATTRIBUTES);
192
193 /*
194 * Ignore append permission for regular files; use write
195 * permission instead.
196 */
197 if (!is_directory && (access_mask & ACL_APPEND_DATA)) {
198 access_mask &= ~ACL_APPEND_DATA;
199 access_mask |= ACL_WRITE_DATA;
200 }
201
202 denied = _acl_denies(aclp, access_mask, cred, file_uid, file_gid,
203 &explicitly_denied);
204
205 if (must_be_owner) {
206 if (file_uid != cred->cr_uid)
207 denied = EPERM;
208 }
209
210 if (!denied)
211 return (0);
212
213 /*
214 * Access failed. Iff it was not denied explicitly and
215 * VEXPLICIT_DENY flag was specified, allow access.
216 */
217 if ((accmode & VEXPLICIT_DENY) && explicitly_denied == 0)
218 return (0);
219
220 accmode &= ~VEXPLICIT_DENY;
221
222 /*
223 * No match. Try to use privileges, if there are any.
224 */
225 if (is_directory) {
226 if ((accmode & VEXEC) && !priv_check_cred(cred,
227 PRIV_VFS_LOOKUP, 0))
228 priv_granted |= VEXEC;
229 } else {
230 if ((accmode & VEXEC) && !priv_check_cred(cred,
231 PRIV_VFS_EXEC, 0))
232 priv_granted |= VEXEC;
233 }
234
235 if ((accmode & VREAD) && !priv_check_cred(cred, PRIV_VFS_READ, 0))
236 priv_granted |= VREAD;
237
238 if ((accmode & (VWRITE | VAPPEND | VDELETE_CHILD)) &&
239 !priv_check_cred(cred, PRIV_VFS_WRITE, 0))
240 priv_granted |= (VWRITE | VAPPEND | VDELETE_CHILD);
241
242 if ((accmode & VADMIN_PERMS) &&
243 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0))
244 priv_granted |= VADMIN_PERMS;
245
246 if ((accmode & VSTAT_PERMS) &&
247 !priv_check_cred(cred, PRIV_VFS_STAT, 0))
248 priv_granted |= VSTAT_PERMS;
249
250 if ((accmode & priv_granted) == accmode) {
251 if (privused != NULL)
252 *privused = 1;
253
254 return (0);
255 }
256
257 if (accmode & (VADMIN_PERMS | VDELETE_CHILD | VDELETE))
258 denied = EPERM;
259 else
260 denied = EACCES;
261
262 return (denied);
263 }
264 #endif /* _KERNEL */
265
266 static int
267 _acl_entry_matches(struct acl_entry *entry, acl_tag_t tag, acl_perm_t perm,
268 acl_entry_type_t entry_type)
269 {
270 if (entry->ae_tag != tag)
271 return (0);
272
273 if (entry->ae_id != ACL_UNDEFINED_ID)
274 return (0);
275
276 if (entry->ae_perm != perm)
277 return (0);
278
279 if (entry->ae_entry_type != entry_type)
280 return (0);
281
282 if (entry->ae_flags != 0)
283 return (0);
284
285 return (1);
286 }
287
288 static struct acl_entry *
289 _acl_append(struct acl *aclp, acl_tag_t tag, acl_perm_t perm,
290 acl_entry_type_t entry_type)
291 {
292 struct acl_entry *entry;
293
294 KASSERT(aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES,
295 ("aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES"));
296
297 entry = &(aclp->acl_entry[aclp->acl_cnt]);
298 aclp->acl_cnt++;
299
300 entry->ae_tag = tag;
301 entry->ae_id = ACL_UNDEFINED_ID;
302 entry->ae_perm = perm;
303 entry->ae_entry_type = entry_type;
304 entry->ae_flags = 0;
305
306 return (entry);
307 }
308
309 static struct acl_entry *
310 _acl_duplicate_entry(struct acl *aclp, int entry_index)
311 {
312 int i;
313
314 KASSERT(aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES,
315 ("aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES"));
316
317 for (i = aclp->acl_cnt; i > entry_index; i--)
318 aclp->acl_entry[i] = aclp->acl_entry[i - 1];
319
320 aclp->acl_cnt++;
321
322 return (&(aclp->acl_entry[entry_index + 1]));
323 }
324
325 /*
326 * Calculate trivial ACL in a manner compatible with PSARC/2010/029.
327 * Note that this results in an ACL different from (but semantically
328 * equal to) the "canonical six" trivial ACL computed using algorithm
329 * described in draft-ietf-nfsv4-minorversion1-03.txt, 3.16.6.2.
330 */
331 void
332 acl_nfs4_trivial_from_mode(struct acl *aclp, mode_t mode)
333 {
334 acl_perm_t user_allow_first = 0, user_deny = 0, group_deny = 0;
335 acl_perm_t user_allow, group_allow, everyone_allow;
336
337 KASSERT(aclp->acl_cnt == 0, ("aclp->acl_cnt == 0"));
338
339 user_allow = group_allow = everyone_allow = ACL_READ_ACL |
340 ACL_READ_ATTRIBUTES | ACL_READ_NAMED_ATTRS | ACL_SYNCHRONIZE;
341 user_allow |= ACL_WRITE_ACL | ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
342 ACL_WRITE_NAMED_ATTRS;
343
344 if (mode & S_IRUSR)
345 user_allow |= ACL_READ_DATA;
346 if (mode & S_IWUSR)
347 user_allow |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
348 if (mode & S_IXUSR)
349 user_allow |= ACL_EXECUTE;
350
351 if (mode & S_IRGRP)
352 group_allow |= ACL_READ_DATA;
353 if (mode & S_IWGRP)
354 group_allow |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
355 if (mode & S_IXGRP)
356 group_allow |= ACL_EXECUTE;
357
358 if (mode & S_IROTH)
359 everyone_allow |= ACL_READ_DATA;
360 if (mode & S_IWOTH)
361 everyone_allow |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
362 if (mode & S_IXOTH)
363 everyone_allow |= ACL_EXECUTE;
364
365 user_deny = ((group_allow | everyone_allow) & ~user_allow);
366 group_deny = everyone_allow & ~group_allow;
367 user_allow_first = group_deny & ~user_deny;
368
369 if (user_allow_first != 0)
370 _acl_append(aclp, ACL_USER_OBJ, user_allow_first, ACL_ENTRY_TYPE_ALLOW);
371 if (user_deny != 0)
372 _acl_append(aclp, ACL_USER_OBJ, user_deny, ACL_ENTRY_TYPE_DENY);
373 if (group_deny != 0)
374 _acl_append(aclp, ACL_GROUP_OBJ, group_deny, ACL_ENTRY_TYPE_DENY);
375 _acl_append(aclp, ACL_USER_OBJ, user_allow, ACL_ENTRY_TYPE_ALLOW);
376 _acl_append(aclp, ACL_GROUP_OBJ, group_allow, ACL_ENTRY_TYPE_ALLOW);
377 _acl_append(aclp, ACL_EVERYONE, everyone_allow, ACL_ENTRY_TYPE_ALLOW);
378 }
379
380 void
381 acl_nfs4_sync_acl_from_mode(struct acl *aclp, mode_t mode, int file_owner_id)
382 {
383 int i, meets, must_append;
384 struct acl_entry *entry, *copy, *previous,
385 *a1, *a2, *a3, *a4, *a5, *a6;
386 mode_t amode;
387 const int READ = 04;
388 const int WRITE = 02;
389 const int EXEC = 01;
390
391 KASSERT(aclp->acl_cnt >= 0, ("aclp->acl_cnt >= 0"));
392 KASSERT(aclp->acl_cnt <= ACL_MAX_ENTRIES,
393 ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
394
395 /*
396 * NFSv4 Minor Version 1, draft-ietf-nfsv4-minorversion1-03.txt
397 *
398 * 3.16.6.3. Applying a Mode to an Existing ACL
399 */
400
401 /*
402 * 1. For each ACE:
403 */
404 for (i = 0; i < aclp->acl_cnt; i++) {
405 entry = &(aclp->acl_entry[i]);
406
407 /*
408 * 1.1. If the type is neither ALLOW or DENY - skip.
409 */
410 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
411 entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
412 continue;
413
414 /*
415 * 1.2. If ACL_ENTRY_INHERIT_ONLY is set - skip.
416 */
417 if (entry->ae_flags & ACL_ENTRY_INHERIT_ONLY)
418 continue;
419
420 /*
421 * 1.3. If ACL_ENTRY_FILE_INHERIT or ACL_ENTRY_DIRECTORY_INHERIT
422 * are set:
423 */
424 if (entry->ae_flags &
425 (ACL_ENTRY_FILE_INHERIT | ACL_ENTRY_DIRECTORY_INHERIT)) {
426 /*
427 * 1.3.1. A copy of the current ACE is made, and placed
428 * in the ACL immediately following the current
429 * ACE.
430 */
431 copy = _acl_duplicate_entry(aclp, i);
432
433 /*
434 * 1.3.2. In the first ACE, the flag
435 * ACL_ENTRY_INHERIT_ONLY is set.
436 */
437 entry->ae_flags |= ACL_ENTRY_INHERIT_ONLY;
438
439 /*
440 * 1.3.3. In the second ACE, the following flags
441 * are cleared:
442 * ACL_ENTRY_FILE_INHERIT,
443 * ACL_ENTRY_DIRECTORY_INHERIT,
444 * ACL_ENTRY_NO_PROPAGATE_INHERIT.
445 */
446 copy->ae_flags &= ~(ACL_ENTRY_FILE_INHERIT |
447 ACL_ENTRY_DIRECTORY_INHERIT |
448 ACL_ENTRY_NO_PROPAGATE_INHERIT);
449
450 /*
451 * The algorithm continues on with the second ACE.
452 */
453 i++;
454 entry = copy;
455 }
456
457 /*
458 * 1.4. If it's owner@, group@ or everyone@ entry, clear
459 * ACL_READ_DATA, ACL_WRITE_DATA, ACL_APPEND_DATA
460 * and ACL_EXECUTE. Continue to the next entry.
461 */
462 if (entry->ae_tag == ACL_USER_OBJ ||
463 entry->ae_tag == ACL_GROUP_OBJ ||
464 entry->ae_tag == ACL_EVERYONE) {
465 entry->ae_perm &= ~(ACL_READ_DATA | ACL_WRITE_DATA |
466 ACL_APPEND_DATA | ACL_EXECUTE);
467 continue;
468 }
469
470 /*
471 * 1.5. Otherwise, if the "who" field did not match one
472 * of OWNER@, GROUP@, EVERYONE@:
473 *
474 * 1.5.1. If the type is ALLOW, check the preceding ACE.
475 * If it does not meet all of the following criteria:
476 */
477 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW)
478 continue;
479
480 meets = 0;
481 if (i > 0) {
482 meets = 1;
483 previous = &(aclp->acl_entry[i - 1]);
484
485 /*
486 * 1.5.1.1. The type field is DENY,
487 */
488 if (previous->ae_entry_type != ACL_ENTRY_TYPE_DENY)
489 meets = 0;
490
491 /*
492 * 1.5.1.2. The "who" field is the same as the current
493 * ACE,
494 *
495 * 1.5.1.3. The flag bit ACE4_IDENTIFIER_GROUP
496 * is the same as it is in the current ACE,
497 * and no other flag bits are set,
498 */
499 if (previous->ae_id != entry->ae_id ||
500 previous->ae_tag != entry->ae_tag)
501 meets = 0;
502
503 if (previous->ae_flags)
504 meets = 0;
505
506 /*
507 * 1.5.1.4. The mask bits are a subset of the mask bits
508 * of the current ACE, and are also subset of
509 * the following: ACL_READ_DATA,
510 * ACL_WRITE_DATA, ACL_APPEND_DATA, ACL_EXECUTE
511 */
512 if (previous->ae_perm & ~(entry->ae_perm))
513 meets = 0;
514
515 if (previous->ae_perm & ~(ACL_READ_DATA |
516 ACL_WRITE_DATA | ACL_APPEND_DATA | ACL_EXECUTE))
517 meets = 0;
518 }
519
520 if (!meets) {
521 /*
522 * Then the ACE of type DENY, with a who equal
523 * to the current ACE, flag bits equal to
524 * (<current ACE flags> & <ACE_IDENTIFIER_GROUP>)
525 * and no mask bits, is prepended.
526 */
527 previous = entry;
528 entry = _acl_duplicate_entry(aclp, i);
529
530 /* Adjust counter, as we've just added an entry. */
531 i++;
532
533 previous->ae_tag = entry->ae_tag;
534 previous->ae_id = entry->ae_id;
535 previous->ae_flags = entry->ae_flags;
536 previous->ae_perm = 0;
537 previous->ae_entry_type = ACL_ENTRY_TYPE_DENY;
538 }
539
540 /*
541 * 1.5.2. The following modifications are made to the prepended
542 * ACE. The intent is to mask the following ACE
543 * to disallow ACL_READ_DATA, ACL_WRITE_DATA,
544 * ACL_APPEND_DATA, or ACL_EXECUTE, based upon the group
545 * permissions of the new mode. As a special case,
546 * if the ACE matches the current owner of the file,
547 * the owner bits are used, rather than the group bits.
548 * This is reflected in the algorithm below.
549 */
550 amode = mode >> 3;
551
552 /*
553 * If ACE4_IDENTIFIER_GROUP is not set, and the "who" field
554 * in ACE matches the owner of the file, we shift amode three
555 * more bits, in order to have the owner permission bits
556 * placed in the three low order bits of amode.
557 */
558 if (entry->ae_tag == ACL_USER && entry->ae_id == file_owner_id)
559 amode = amode >> 3;
560
561 if (entry->ae_perm & ACL_READ_DATA) {
562 if (amode & READ)
563 previous->ae_perm &= ~ACL_READ_DATA;
564 else
565 previous->ae_perm |= ACL_READ_DATA;
566 }
567
568 if (entry->ae_perm & ACL_WRITE_DATA) {
569 if (amode & WRITE)
570 previous->ae_perm &= ~ACL_WRITE_DATA;
571 else
572 previous->ae_perm |= ACL_WRITE_DATA;
573 }
574
575 if (entry->ae_perm & ACL_APPEND_DATA) {
576 if (amode & WRITE)
577 previous->ae_perm &= ~ACL_APPEND_DATA;
578 else
579 previous->ae_perm |= ACL_APPEND_DATA;
580 }
581
582 if (entry->ae_perm & ACL_EXECUTE) {
583 if (amode & EXEC)
584 previous->ae_perm &= ~ACL_EXECUTE;
585 else
586 previous->ae_perm |= ACL_EXECUTE;
587 }
588
589 /*
590 * 1.5.3. If ACE4_IDENTIFIER_GROUP is set in the flags
591 * of the ALLOW ace:
592 *
593 * XXX: This point is not there in the Falkner's draft.
594 */
595 if (entry->ae_tag == ACL_GROUP &&
596 entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW) {
597 mode_t extramode, ownermode;
598 extramode = (mode >> 3) & 07;
599 ownermode = mode >> 6;
600 extramode &= ~ownermode;
601
602 if (extramode) {
603 if (extramode & READ) {
604 entry->ae_perm &= ~ACL_READ_DATA;
605 previous->ae_perm &= ~ACL_READ_DATA;
606 }
607
608 if (extramode & WRITE) {
609 entry->ae_perm &=
610 ~(ACL_WRITE_DATA | ACL_APPEND_DATA);
611 previous->ae_perm &=
612 ~(ACL_WRITE_DATA | ACL_APPEND_DATA);
613 }
614
615 if (extramode & EXEC) {
616 entry->ae_perm &= ~ACL_EXECUTE;
617 previous->ae_perm &= ~ACL_EXECUTE;
618 }
619 }
620 }
621 }
622
623 /*
624 * 2. If there at least six ACEs, the final six ACEs are examined.
625 * If they are not equal to what we want, append six ACEs.
626 */
627 must_append = 0;
628 if (aclp->acl_cnt < 6) {
629 must_append = 1;
630 } else {
631 a6 = &(aclp->acl_entry[aclp->acl_cnt - 1]);
632 a5 = &(aclp->acl_entry[aclp->acl_cnt - 2]);
633 a4 = &(aclp->acl_entry[aclp->acl_cnt - 3]);
634 a3 = &(aclp->acl_entry[aclp->acl_cnt - 4]);
635 a2 = &(aclp->acl_entry[aclp->acl_cnt - 5]);
636 a1 = &(aclp->acl_entry[aclp->acl_cnt - 6]);
637
638 if (!_acl_entry_matches(a1, ACL_USER_OBJ, 0,
639 ACL_ENTRY_TYPE_DENY))
640 must_append = 1;
641 if (!_acl_entry_matches(a2, ACL_USER_OBJ, ACL_WRITE_ACL |
642 ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
643 ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_ALLOW))
644 must_append = 1;
645 if (!_acl_entry_matches(a3, ACL_GROUP_OBJ, 0,
646 ACL_ENTRY_TYPE_DENY))
647 must_append = 1;
648 if (!_acl_entry_matches(a4, ACL_GROUP_OBJ, 0,
649 ACL_ENTRY_TYPE_ALLOW))
650 must_append = 1;
651 if (!_acl_entry_matches(a5, ACL_EVERYONE, ACL_WRITE_ACL |
652 ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
653 ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_DENY))
654 must_append = 1;
655 if (!_acl_entry_matches(a6, ACL_EVERYONE, ACL_READ_ACL |
656 ACL_READ_ATTRIBUTES | ACL_READ_NAMED_ATTRS |
657 ACL_SYNCHRONIZE, ACL_ENTRY_TYPE_ALLOW))
658 must_append = 1;
659 }
660
661 if (must_append) {
662 KASSERT(aclp->acl_cnt + 6 <= ACL_MAX_ENTRIES,
663 ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
664
665 a1 = _acl_append(aclp, ACL_USER_OBJ, 0, ACL_ENTRY_TYPE_DENY);
666 a2 = _acl_append(aclp, ACL_USER_OBJ, ACL_WRITE_ACL |
667 ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
668 ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_ALLOW);
669 a3 = _acl_append(aclp, ACL_GROUP_OBJ, 0, ACL_ENTRY_TYPE_DENY);
670 a4 = _acl_append(aclp, ACL_GROUP_OBJ, 0, ACL_ENTRY_TYPE_ALLOW);
671 a5 = _acl_append(aclp, ACL_EVERYONE, ACL_WRITE_ACL |
672 ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
673 ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_DENY);
674 a6 = _acl_append(aclp, ACL_EVERYONE, ACL_READ_ACL |
675 ACL_READ_ATTRIBUTES | ACL_READ_NAMED_ATTRS |
676 ACL_SYNCHRONIZE, ACL_ENTRY_TYPE_ALLOW);
677
678 KASSERT(a1 != NULL && a2 != NULL && a3 != NULL && a4 != NULL &&
679 a5 != NULL && a6 != NULL, ("couldn't append to ACL."));
680 }
681
682 /*
683 * 3. The final six ACEs are adjusted according to the incoming mode.
684 */
685 if (mode & S_IRUSR)
686 a2->ae_perm |= ACL_READ_DATA;
687 else
688 a1->ae_perm |= ACL_READ_DATA;
689 if (mode & S_IWUSR)
690 a2->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
691 else
692 a1->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
693 if (mode & S_IXUSR)
694 a2->ae_perm |= ACL_EXECUTE;
695 else
696 a1->ae_perm |= ACL_EXECUTE;
697
698 if (mode & S_IRGRP)
699 a4->ae_perm |= ACL_READ_DATA;
700 else
701 a3->ae_perm |= ACL_READ_DATA;
702 if (mode & S_IWGRP)
703 a4->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
704 else
705 a3->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
706 if (mode & S_IXGRP)
707 a4->ae_perm |= ACL_EXECUTE;
708 else
709 a3->ae_perm |= ACL_EXECUTE;
710
711 if (mode & S_IROTH)
712 a6->ae_perm |= ACL_READ_DATA;
713 else
714 a5->ae_perm |= ACL_READ_DATA;
715 if (mode & S_IWOTH)
716 a6->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
717 else
718 a5->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
719 if (mode & S_IXOTH)
720 a6->ae_perm |= ACL_EXECUTE;
721 else
722 a5->ae_perm |= ACL_EXECUTE;
723 }
724
725 void
726 acl_nfs4_sync_mode_from_acl(mode_t *_mode, const struct acl *aclp)
727 {
728 int i;
729 mode_t old_mode = *_mode, mode = 0, seen = 0;
730 const struct acl_entry *entry;
731
732 KASSERT(aclp->acl_cnt <= ACL_MAX_ENTRIES,
733 ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
734
735 /*
736 * NFSv4 Minor Version 1, draft-ietf-nfsv4-minorversion1-03.txt
737 *
738 * 3.16.6.1. Recomputing mode upon SETATTR of ACL
739 */
740
741 for (i = 0; i < aclp->acl_cnt; i++) {
742 entry = &(aclp->acl_entry[i]);
743
744 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
745 entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
746 continue;
747
748 if (entry->ae_flags & ACL_ENTRY_INHERIT_ONLY)
749 continue;
750
751 if (entry->ae_tag == ACL_USER_OBJ) {
752 if ((entry->ae_perm & ACL_READ_DATA) &&
753 ((seen & S_IRUSR) == 0)) {
754 seen |= S_IRUSR;
755 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
756 mode |= S_IRUSR;
757 }
758 if ((entry->ae_perm & ACL_WRITE_DATA) &&
759 ((seen & S_IWUSR) == 0)) {
760 seen |= S_IWUSR;
761 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
762 mode |= S_IWUSR;
763 }
764 if ((entry->ae_perm & ACL_EXECUTE) &&
765 ((seen & S_IXUSR) == 0)) {
766 seen |= S_IXUSR;
767 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
768 mode |= S_IXUSR;
769 }
770 } else if (entry->ae_tag == ACL_GROUP_OBJ) {
771 if ((entry->ae_perm & ACL_READ_DATA) &&
772 ((seen & S_IRGRP) == 0)) {
773 seen |= S_IRGRP;
774 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
775 mode |= S_IRGRP;
776 }
777 if ((entry->ae_perm & ACL_WRITE_DATA) &&
778 ((seen & S_IWGRP) == 0)) {
779 seen |= S_IWGRP;
780 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
781 mode |= S_IWGRP;
782 }
783 if ((entry->ae_perm & ACL_EXECUTE) &&
784 ((seen & S_IXGRP) == 0)) {
785 seen |= S_IXGRP;
786 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
787 mode |= S_IXGRP;
788 }
789 } else if (entry->ae_tag == ACL_EVERYONE) {
790 if (entry->ae_perm & ACL_READ_DATA) {
791 if ((seen & S_IRUSR) == 0) {
792 seen |= S_IRUSR;
793 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
794 mode |= S_IRUSR;
795 }
796 if ((seen & S_IRGRP) == 0) {
797 seen |= S_IRGRP;
798 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
799 mode |= S_IRGRP;
800 }
801 if ((seen & S_IROTH) == 0) {
802 seen |= S_IROTH;
803 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
804 mode |= S_IROTH;
805 }
806 }
807 if (entry->ae_perm & ACL_WRITE_DATA) {
808 if ((seen & S_IWUSR) == 0) {
809 seen |= S_IWUSR;
810 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
811 mode |= S_IWUSR;
812 }
813 if ((seen & S_IWGRP) == 0) {
814 seen |= S_IWGRP;
815 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
816 mode |= S_IWGRP;
817 }
818 if ((seen & S_IWOTH) == 0) {
819 seen |= S_IWOTH;
820 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
821 mode |= S_IWOTH;
822 }
823 }
824 if (entry->ae_perm & ACL_EXECUTE) {
825 if ((seen & S_IXUSR) == 0) {
826 seen |= S_IXUSR;
827 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
828 mode |= S_IXUSR;
829 }
830 if ((seen & S_IXGRP) == 0) {
831 seen |= S_IXGRP;
832 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
833 mode |= S_IXGRP;
834 }
835 if ((seen & S_IXOTH) == 0) {
836 seen |= S_IXOTH;
837 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
838 mode |= S_IXOTH;
839 }
840 }
841 }
842 }
843
844 *_mode = mode | (old_mode & ACL_PRESERVE_MASK);
845 }
846
847 void
848 acl_nfs4_compute_inherited_acl(const struct acl *parent_aclp,
849 struct acl *child_aclp, mode_t mode, int file_owner_id,
850 int is_directory)
851 {
852 int i, flags;
853 const struct acl_entry *parent_entry;
854 struct acl_entry *entry, *copy;
855
856 KASSERT(child_aclp->acl_cnt == 0, ("child_aclp->acl_cnt == 0"));
857 KASSERT(parent_aclp->acl_cnt <= ACL_MAX_ENTRIES,
858 ("parent_aclp->acl_cnt <= ACL_MAX_ENTRIES"));
859
860 /*
861 * NFSv4 Minor Version 1, draft-ietf-nfsv4-minorversion1-03.txt
862 *
863 * 3.16.6.2. Applying the mode given to CREATE or OPEN
864 * to an inherited ACL
865 */
866
867 /*
868 * 1. Form an ACL that is the concatenation of all inheritable ACEs.
869 */
870 for (i = 0; i < parent_aclp->acl_cnt; i++) {
871 parent_entry = &(parent_aclp->acl_entry[i]);
872 flags = parent_entry->ae_flags;
873
874 /*
875 * Entry is not inheritable at all.
876 */
877 if ((flags & (ACL_ENTRY_DIRECTORY_INHERIT |
878 ACL_ENTRY_FILE_INHERIT)) == 0)
879 continue;
880
881 /*
882 * We're creating a file, but entry is not inheritable
883 * by files.
884 */
885 if (!is_directory && (flags & ACL_ENTRY_FILE_INHERIT) == 0)
886 continue;
887
888 /*
889 * Entry is inheritable only by files, but has NO_PROPAGATE
890 * flag set, and we're creating a directory, so it wouldn't
891 * propagate to any file in that directory anyway.
892 */
893 if (is_directory &&
894 (flags & ACL_ENTRY_DIRECTORY_INHERIT) == 0 &&
895 (flags & ACL_ENTRY_NO_PROPAGATE_INHERIT))
896 continue;
897
898 KASSERT(child_aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES,
899 ("child_aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES"));
900 child_aclp->acl_entry[child_aclp->acl_cnt] = *parent_entry;
901 child_aclp->acl_cnt++;
902 }
903
904 /*
905 * 2. For each entry in the new ACL, adjust its flags, possibly
906 * creating two entries in place of one.
907 */
908 for (i = 0; i < child_aclp->acl_cnt; i++) {
909 entry = &(child_aclp->acl_entry[i]);
910
911 /*
912 * This is not in the specification, but SunOS
913 * apparently does that.
914 */
915 if (((entry->ae_flags & ACL_ENTRY_NO_PROPAGATE_INHERIT) ||
916 !is_directory) &&
917 entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
918 entry->ae_perm &= ~(ACL_WRITE_ACL | ACL_WRITE_OWNER);
919
920 /*
921 * 2.A. If the ACL_ENTRY_NO_PROPAGATE_INHERIT is set, or if the object
922 * being created is not a directory, then clear the
923 * following flags: ACL_ENTRY_NO_PROPAGATE_INHERIT,
924 * ACL_ENTRY_FILE_INHERIT, ACL_ENTRY_DIRECTORY_INHERIT,
925 * ACL_ENTRY_INHERIT_ONLY.
926 */
927 if (entry->ae_flags & ACL_ENTRY_NO_PROPAGATE_INHERIT ||
928 !is_directory) {
929 entry->ae_flags &= ~(ACL_ENTRY_NO_PROPAGATE_INHERIT |
930 ACL_ENTRY_FILE_INHERIT | ACL_ENTRY_DIRECTORY_INHERIT |
931 ACL_ENTRY_INHERIT_ONLY);
932
933 /*
934 * Continue on to the next ACE.
935 */
936 continue;
937 }
938
939 /*
940 * 2.B. If the object is a directory and ACL_ENTRY_FILE_INHERIT
941 * is set, but ACL_ENTRY_NO_PROPAGATE_INHERIT is not set, ensure
942 * that ACL_ENTRY_INHERIT_ONLY is set. Continue to the
943 * next ACE. Otherwise...
944 */
945 /*
946 * XXX: Read it again and make sure what does the "otherwise"
947 * apply to.
948 */
949 if (is_directory &&
950 (entry->ae_flags & ACL_ENTRY_FILE_INHERIT) &&
951 ((entry->ae_flags & ACL_ENTRY_DIRECTORY_INHERIT) == 0)) {
952 entry->ae_flags |= ACL_ENTRY_INHERIT_ONLY;
953 continue;
954 }
955
956 /*
957 * 2.C. If the type of the ACE is neither ALLOW nor deny,
958 * then continue.
959 */
960 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
961 entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
962 continue;
963
964 /*
965 * 2.D. Copy the original ACE into a second, adjacent ACE.
966 */
967 copy = _acl_duplicate_entry(child_aclp, i);
968
969 /*
970 * 2.E. On the first ACE, ensure that ACL_ENTRY_INHERIT_ONLY
971 * is set.
972 */
973 entry->ae_flags |= ACL_ENTRY_INHERIT_ONLY;
974
975 /*
976 * 2.F. On the second ACE, clear the following flags:
977 * ACL_ENTRY_NO_PROPAGATE_INHERIT, ACL_ENTRY_FILE_INHERIT,
978 * ACL_ENTRY_DIRECTORY_INHERIT, ACL_ENTRY_INHERIT_ONLY.
979 */
980 copy->ae_flags &= ~(ACL_ENTRY_NO_PROPAGATE_INHERIT |
981 ACL_ENTRY_FILE_INHERIT | ACL_ENTRY_DIRECTORY_INHERIT |
982 ACL_ENTRY_INHERIT_ONLY);
983
984 /*
985 * 2.G. On the second ACE, if the type is ALLOW,
986 * an implementation MAY clear the following
987 * mask bits: ACL_WRITE_ACL, ACL_WRITE_OWNER.
988 */
989 if (copy->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
990 copy->ae_perm &= ~(ACL_WRITE_ACL | ACL_WRITE_OWNER);
991
992 /*
993 * Increment the counter to skip the copied entry.
994 */
995 i++;
996 }
997
998 /*
999 * 3. To ensure that the mode is honored, apply the algorithm describe
1000 * in Section 2.16.6.3, using the mode that is to be used for file
1001 * creation.
1002 */
1003 acl_nfs4_sync_acl_from_mode(child_aclp, mode, file_owner_id);
1004 }
1005
1006 #ifdef _KERNEL
1007 static int
1008 _acls_are_equal(const struct acl *a, const struct acl *b)
1009 {
1010 int i;
1011 const struct acl_entry *entrya, *entryb;
1012
1013 if (a->acl_cnt != b->acl_cnt)
1014 return (0);
1015
1016 for (i = 0; i < b->acl_cnt; i++) {
1017 entrya = &(a->acl_entry[i]);
1018 entryb = &(b->acl_entry[i]);
1019
1020 if (entrya->ae_tag != entryb->ae_tag ||
1021 entrya->ae_id != entryb->ae_id ||
1022 entrya->ae_perm != entryb->ae_perm ||
1023 entrya->ae_entry_type != entryb->ae_entry_type ||
1024 entrya->ae_flags != entryb->ae_flags)
1025 return (0);
1026 }
1027
1028 return (1);
1029 }
1030
1031 /*
1032 * This routine is used to determine whether to remove entry_type attribute
1033 * that stores ACL contents.
1034 */
1035 int
1036 acl_nfs4_is_trivial(const struct acl *aclp, int file_owner_id)
1037 {
1038 int trivial;
1039 mode_t tmpmode = 0;
1040 struct acl *tmpaclp;
1041
1042 if (aclp->acl_cnt != 6)
1043 return (0);
1044
1045 /*
1046 * Compute the mode from the ACL, then compute new ACL from that mode.
1047 * If the ACLs are identical, then the ACL is trivial.
1048 *
1049 * XXX: I guess there is a faster way to do this. However, even
1050 * this slow implementation significantly speeds things up
1051 * for files that don't have any entry_type ACL entries - it's
1052 * critical for performance to not use EA when they are not
1053 * needed.
1054 */
1055 tmpaclp = acl_alloc(M_WAITOK | M_ZERO);
1056 acl_nfs4_sync_mode_from_acl(&tmpmode, aclp);
1057 acl_nfs4_sync_acl_from_mode(tmpaclp, tmpmode, file_owner_id);
1058 trivial = _acls_are_equal(aclp, tmpaclp);
1059 acl_free(tmpaclp);
1060
1061 return (trivial);
1062 }
1063 #endif /* _KERNEL */
1064
1065 int
1066 acl_nfs4_check(const struct acl *aclp, int is_directory)
1067 {
1068 int i;
1069 const struct acl_entry *entry;
1070
1071 /*
1072 * The spec doesn't seem to say anything about ACL validity.
1073 * It seems there is not much to do here. There is even no need
1074 * to count "owner@" or "everyone@" (ACL_USER_OBJ and ACL_EVERYONE)
1075 * entries, as there can be several of them and that's perfectly
1076 * valid. There can be none of them too. Really.
1077 */
1078
1079 if (aclp->acl_cnt > ACL_MAX_ENTRIES || aclp->acl_cnt <= 0)
1080 return (EINVAL);
1081
1082 for (i = 0; i < aclp->acl_cnt; i++) {
1083 entry = &(aclp->acl_entry[i]);
1084
1085 switch (entry->ae_tag) {
1086 case ACL_USER_OBJ:
1087 case ACL_GROUP_OBJ:
1088 case ACL_EVERYONE:
1089 if (entry->ae_id != ACL_UNDEFINED_ID)
1090 return (EINVAL);
1091 break;
1092
1093 case ACL_USER:
1094 case ACL_GROUP:
1095 if (entry->ae_id == ACL_UNDEFINED_ID)
1096 return (EINVAL);
1097 break;
1098
1099 default:
1100 return (EINVAL);
1101 }
1102
1103 if ((entry->ae_perm | ACL_NFS4_PERM_BITS) != ACL_NFS4_PERM_BITS)
1104 return (EINVAL);
1105
1106 /*
1107 * Disallow ACL_ENTRY_TYPE_AUDIT and ACL_ENTRY_TYPE_ALARM for now.
1108 */
1109 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
1110 entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
1111 return (EINVAL);
1112
1113 if ((entry->ae_flags | ACL_FLAGS_BITS) != ACL_FLAGS_BITS)
1114 return (EINVAL);
1115
1116 /* Disallow unimplemented flags. */
1117 if (entry->ae_flags & (ACL_ENTRY_SUCCESSFUL_ACCESS |
1118 ACL_ENTRY_FAILED_ACCESS))
1119 return (EINVAL);
1120
1121 /* Disallow flags not allowed for ordinary files. */
1122 if (!is_directory) {
1123 if (entry->ae_flags & (ACL_ENTRY_FILE_INHERIT |
1124 ACL_ENTRY_DIRECTORY_INHERIT |
1125 ACL_ENTRY_NO_PROPAGATE_INHERIT | ACL_ENTRY_INHERIT_ONLY))
1126 return (EINVAL);
1127 }
1128 }
1129
1130 return (0);
1131 }
Cache object: 19b0cd139a77a2fbd09f727f319f0f43
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