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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Nathan Scott7b718762005-11-02 14:58:39 +11002 * Copyright (c) 2001-2002,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 *
Nathan Scott7b718762005-11-02 14:58:39 +11005 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 * published by the Free Software Foundation.
8 *
Nathan Scott7b718762005-11-02 14:58:39 +11009 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 *
Nathan Scott7b718762005-11-02 14:58:39 +110014 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include "xfs.h"
Nathan Scotta844f452005-11-02 14:38:42 +110019#include "xfs_fs.h"
20#include "xfs_types.h"
21#include "xfs_bit.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include "xfs_inum.h"
Nathan Scotta844f452005-11-02 14:38:42 +110023#include "xfs_ag.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include "xfs_dir2.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include "xfs_bmap_btree.h"
Nathan Scotta844f452005-11-02 14:38:42 +110026#include "xfs_alloc_btree.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include "xfs_ialloc_btree.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include "xfs_dir2_sf.h"
Nathan Scotta844f452005-11-02 14:38:42 +110029#include "xfs_attr_sf.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include "xfs_dinode.h"
31#include "xfs_inode.h"
Nathan Scotta844f452005-11-02 14:38:42 +110032#include "xfs_btree.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include "xfs_acl.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include "xfs_attr.h"
35
Randy Dunlap16f7e0f2006-01-11 12:17:46 -080036#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037#include <linux/posix_acl_xattr.h>
38
Nathan Scott67fcaa72006-06-09 17:00:52 +100039STATIC int xfs_acl_setmode(bhv_vnode_t *, xfs_acl_t *, int *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070040STATIC void xfs_acl_filter_mode(mode_t, xfs_acl_t *);
41STATIC void xfs_acl_get_endian(xfs_acl_t *);
42STATIC int xfs_acl_access(uid_t, gid_t, xfs_acl_t *, mode_t, cred_t *);
43STATIC int xfs_acl_invalid(xfs_acl_t *);
44STATIC void xfs_acl_sync_mode(mode_t, xfs_acl_t *);
Nathan Scott67fcaa72006-06-09 17:00:52 +100045STATIC void xfs_acl_get_attr(bhv_vnode_t *, xfs_acl_t *, int, int, int *);
46STATIC void xfs_acl_set_attr(bhv_vnode_t *, xfs_acl_t *, int, int *);
47STATIC int xfs_acl_allow_set(bhv_vnode_t *, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
49kmem_zone_t *xfs_acl_zone;
50
51
52/*
53 * Test for existence of access ACL attribute as efficiently as possible.
54 */
55int
56xfs_acl_vhasacl_access(
Nathan Scott67fcaa72006-06-09 17:00:52 +100057 bhv_vnode_t *vp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070058{
59 int error;
60
61 xfs_acl_get_attr(vp, NULL, _ACL_TYPE_ACCESS, ATTR_KERNOVAL, &error);
62 return (error == 0);
63}
64
65/*
66 * Test for existence of default ACL attribute as efficiently as possible.
67 */
68int
69xfs_acl_vhasacl_default(
Nathan Scott67fcaa72006-06-09 17:00:52 +100070 bhv_vnode_t *vp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070071{
72 int error;
73
Christoph Hellwig0432dab2005-09-02 16:46:51 +100074 if (!VN_ISDIR(vp))
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 return 0;
76 xfs_acl_get_attr(vp, NULL, _ACL_TYPE_DEFAULT, ATTR_KERNOVAL, &error);
77 return (error == 0);
78}
79
80/*
81 * Convert from extended attribute representation to in-memory for XFS.
82 */
83STATIC int
84posix_acl_xattr_to_xfs(
85 posix_acl_xattr_header *src,
86 size_t size,
87 xfs_acl_t *dest)
88{
89 posix_acl_xattr_entry *src_entry;
90 xfs_acl_entry_t *dest_entry;
91 int n;
92
93 if (!src || !dest)
94 return EINVAL;
95
96 if (size < sizeof(posix_acl_xattr_header))
97 return EINVAL;
98
99 if (src->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION))
100 return EOPNOTSUPP;
101
102 memset(dest, 0, sizeof(xfs_acl_t));
103 dest->acl_cnt = posix_acl_xattr_count(size);
104 if (dest->acl_cnt < 0 || dest->acl_cnt > XFS_ACL_MAX_ENTRIES)
105 return EINVAL;
106
107 /*
108 * acl_set_file(3) may request that we set default ACLs with
109 * zero length -- defend (gracefully) against that here.
110 */
111 if (!dest->acl_cnt)
112 return 0;
113
114 src_entry = (posix_acl_xattr_entry *)((char *)src + sizeof(*src));
115 dest_entry = &dest->acl_entry[0];
116
117 for (n = 0; n < dest->acl_cnt; n++, src_entry++, dest_entry++) {
118 dest_entry->ae_perm = le16_to_cpu(src_entry->e_perm);
119 if (_ACL_PERM_INVALID(dest_entry->ae_perm))
120 return EINVAL;
121 dest_entry->ae_tag = le16_to_cpu(src_entry->e_tag);
122 switch(dest_entry->ae_tag) {
123 case ACL_USER:
124 case ACL_GROUP:
125 dest_entry->ae_id = le32_to_cpu(src_entry->e_id);
126 break;
127 case ACL_USER_OBJ:
128 case ACL_GROUP_OBJ:
129 case ACL_MASK:
130 case ACL_OTHER:
131 dest_entry->ae_id = ACL_UNDEFINED_ID;
132 break;
133 default:
134 return EINVAL;
135 }
136 }
137 if (xfs_acl_invalid(dest))
138 return EINVAL;
139
140 return 0;
141}
142
143/*
Nathan Scott380b5dc2005-11-02 11:43:18 +1100144 * Comparison function called from xfs_sort().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145 * Primary key is ae_tag, secondary key is ae_id.
146 */
147STATIC int
148xfs_acl_entry_compare(
149 const void *va,
150 const void *vb)
151{
152 xfs_acl_entry_t *a = (xfs_acl_entry_t *)va,
153 *b = (xfs_acl_entry_t *)vb;
154
155 if (a->ae_tag == b->ae_tag)
156 return (a->ae_id - b->ae_id);
157 return (a->ae_tag - b->ae_tag);
158}
159
160/*
161 * Convert from in-memory XFS to extended attribute representation.
162 */
163STATIC int
164posix_acl_xfs_to_xattr(
165 xfs_acl_t *src,
166 posix_acl_xattr_header *dest,
167 size_t size)
168{
169 int n;
170 size_t new_size = posix_acl_xattr_size(src->acl_cnt);
171 posix_acl_xattr_entry *dest_entry;
172 xfs_acl_entry_t *src_entry;
173
174 if (size < new_size)
175 return -ERANGE;
176
177 /* Need to sort src XFS ACL by <ae_tag,ae_id> */
Nathan Scott380b5dc2005-11-02 11:43:18 +1100178 xfs_sort(src->acl_entry, src->acl_cnt, sizeof(src->acl_entry[0]),
179 xfs_acl_entry_compare);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180
181 dest->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION);
182 dest_entry = &dest->a_entries[0];
183 src_entry = &src->acl_entry[0];
184 for (n = 0; n < src->acl_cnt; n++, dest_entry++, src_entry++) {
185 dest_entry->e_perm = cpu_to_le16(src_entry->ae_perm);
186 if (_ACL_PERM_INVALID(src_entry->ae_perm))
187 return -EINVAL;
188 dest_entry->e_tag = cpu_to_le16(src_entry->ae_tag);
189 switch (src_entry->ae_tag) {
190 case ACL_USER:
191 case ACL_GROUP:
192 dest_entry->e_id = cpu_to_le32(src_entry->ae_id);
193 break;
194 case ACL_USER_OBJ:
195 case ACL_GROUP_OBJ:
196 case ACL_MASK:
197 case ACL_OTHER:
198 dest_entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID);
199 break;
200 default:
201 return -EINVAL;
202 }
203 }
204 return new_size;
205}
206
207int
208xfs_acl_vget(
Nathan Scott67fcaa72006-06-09 17:00:52 +1000209 bhv_vnode_t *vp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210 void *acl,
211 size_t size,
212 int kind)
213{
214 int error;
215 xfs_acl_t *xfs_acl = NULL;
216 posix_acl_xattr_header *ext_acl = acl;
217 int flags = 0;
218
219 VN_HOLD(vp);
220 if(size) {
221 if (!(_ACL_ALLOC(xfs_acl))) {
222 error = ENOMEM;
223 goto out;
224 }
225 memset(xfs_acl, 0, sizeof(xfs_acl_t));
226 } else
227 flags = ATTR_KERNOVAL;
228
229 xfs_acl_get_attr(vp, xfs_acl, kind, flags, &error);
230 if (error)
231 goto out;
232
233 if (!size) {
234 error = -posix_acl_xattr_size(XFS_ACL_MAX_ENTRIES);
235 } else {
236 if (xfs_acl_invalid(xfs_acl)) {
237 error = EINVAL;
238 goto out;
239 }
240 if (kind == _ACL_TYPE_ACCESS) {
Nathan Scott8285fb52006-06-09 17:07:12 +1000241 bhv_vattr_t va;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242
243 va.va_mask = XFS_AT_MODE;
Nathan Scott67fcaa72006-06-09 17:00:52 +1000244 error = bhv_vop_getattr(vp, &va, 0, sys_cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 if (error)
246 goto out;
247 xfs_acl_sync_mode(va.va_mode, xfs_acl);
248 }
249 error = -posix_acl_xfs_to_xattr(xfs_acl, ext_acl, size);
250 }
251out:
252 VN_RELE(vp);
253 if(xfs_acl)
254 _ACL_FREE(xfs_acl);
255 return -error;
256}
257
258int
259xfs_acl_vremove(
Nathan Scott67fcaa72006-06-09 17:00:52 +1000260 bhv_vnode_t *vp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 int kind)
262{
263 int error;
264
265 VN_HOLD(vp);
266 error = xfs_acl_allow_set(vp, kind);
267 if (!error) {
Nathan Scott67fcaa72006-06-09 17:00:52 +1000268 error = bhv_vop_attr_remove(vp, kind == _ACL_TYPE_DEFAULT?
269 SGI_ACL_DEFAULT: SGI_ACL_FILE,
270 ATTR_ROOT, sys_cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 if (error == ENOATTR)
272 error = 0; /* 'scool */
273 }
274 VN_RELE(vp);
275 return -error;
276}
277
278int
279xfs_acl_vset(
Nathan Scott67fcaa72006-06-09 17:00:52 +1000280 bhv_vnode_t *vp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 void *acl,
282 size_t size,
283 int kind)
284{
285 posix_acl_xattr_header *ext_acl = acl;
286 xfs_acl_t *xfs_acl;
287 int error;
288 int basicperms = 0; /* more than std unix perms? */
289
290 if (!acl)
291 return -EINVAL;
292
293 if (!(_ACL_ALLOC(xfs_acl)))
294 return -ENOMEM;
295
296 error = posix_acl_xattr_to_xfs(ext_acl, size, xfs_acl);
297 if (error) {
298 _ACL_FREE(xfs_acl);
299 return -error;
300 }
301 if (!xfs_acl->acl_cnt) {
302 _ACL_FREE(xfs_acl);
303 return 0;
304 }
305
306 VN_HOLD(vp);
307 error = xfs_acl_allow_set(vp, kind);
308 if (error)
309 goto out;
310
311 /* Incoming ACL exists, set file mode based on its value */
312 if (kind == _ACL_TYPE_ACCESS)
313 xfs_acl_setmode(vp, xfs_acl, &basicperms);
314
315 /*
316 * If we have more than std unix permissions, set up the actual attr.
317 * Otherwise, delete any existing attr. This prevents us from
318 * having actual attrs for permissions that can be stored in the
319 * standard permission bits.
320 */
321 if (!basicperms) {
322 xfs_acl_set_attr(vp, xfs_acl, kind, &error);
323 } else {
324 xfs_acl_vremove(vp, _ACL_TYPE_ACCESS);
325 }
326
327out:
328 VN_RELE(vp);
329 _ACL_FREE(xfs_acl);
330 return -error;
331}
332
333int
334xfs_acl_iaccess(
335 xfs_inode_t *ip,
336 mode_t mode,
337 cred_t *cr)
338{
339 xfs_acl_t *acl;
340 int rval;
341
342 if (!(_ACL_ALLOC(acl)))
343 return -1;
344
345 /* If the file has no ACL return -1. */
346 rval = sizeof(xfs_acl_t);
347 if (xfs_attr_fetch(ip, SGI_ACL_FILE, SGI_ACL_FILE_SIZE,
348 (char *)acl, &rval, ATTR_ROOT | ATTR_KERNACCESS, cr)) {
349 _ACL_FREE(acl);
350 return -1;
351 }
352 xfs_acl_get_endian(acl);
353
354 /* If the file has an empty ACL return -1. */
355 if (acl->acl_cnt == XFS_ACL_NOT_PRESENT) {
356 _ACL_FREE(acl);
357 return -1;
358 }
359
360 /* Synchronize ACL with mode bits */
361 xfs_acl_sync_mode(ip->i_d.di_mode, acl);
362
363 rval = xfs_acl_access(ip->i_d.di_uid, ip->i_d.di_gid, acl, mode, cr);
364 _ACL_FREE(acl);
365 return rval;
366}
367
368STATIC int
369xfs_acl_allow_set(
Nathan Scott67fcaa72006-06-09 17:00:52 +1000370 bhv_vnode_t *vp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 int kind)
372{
Nathan Scott8285fb52006-06-09 17:07:12 +1000373 bhv_vattr_t va;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 int error;
375
376 if (vp->v_inode.i_flags & (S_IMMUTABLE|S_APPEND))
377 return EPERM;
Christoph Hellwig0432dab2005-09-02 16:46:51 +1000378 if (kind == _ACL_TYPE_DEFAULT && !VN_ISDIR(vp))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379 return ENOTDIR;
380 if (vp->v_vfsp->vfs_flag & VFS_RDONLY)
381 return EROFS;
382 va.va_mask = XFS_AT_UID;
Nathan Scott67fcaa72006-06-09 17:00:52 +1000383 error = bhv_vop_getattr(vp, &va, 0, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 if (error)
385 return error;
386 if (va.va_uid != current->fsuid && !capable(CAP_FOWNER))
387 return EPERM;
388 return error;
389}
390
391/*
392 * The access control process to determine the access permission:
393 * if uid == file owner id, use the file owner bits.
394 * if gid == file owner group id, use the file group bits.
Nathan Scottc41564b2006-03-29 08:55:14 +1000395 * scan ACL for a matching user or group, and use matched entry
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396 * permission. Use total permissions of all matching group entries,
397 * until all acl entries are exhausted. The final permission produced
398 * by matching acl entry or entries needs to be & with group permission.
399 * if not owner, owning group, or matching entry in ACL, use file
400 * other bits.
401 */
402STATIC int
403xfs_acl_capability_check(
404 mode_t mode,
405 cred_t *cr)
406{
407 if ((mode & ACL_READ) && !capable_cred(cr, CAP_DAC_READ_SEARCH))
408 return EACCES;
409 if ((mode & ACL_WRITE) && !capable_cred(cr, CAP_DAC_OVERRIDE))
410 return EACCES;
411 if ((mode & ACL_EXECUTE) && !capable_cred(cr, CAP_DAC_OVERRIDE))
412 return EACCES;
413
414 return 0;
415}
416
417/*
418 * Note: cr is only used here for the capability check if the ACL test fails.
419 * It is not used to find out the credentials uid or groups etc, as was
420 * done in IRIX. It is assumed that the uid and groups for the current
421 * thread are taken from "current" instead of the cr parameter.
422 */
423STATIC int
424xfs_acl_access(
425 uid_t fuid,
426 gid_t fgid,
427 xfs_acl_t *fap,
428 mode_t md,
429 cred_t *cr)
430{
431 xfs_acl_entry_t matched;
432 int i, allows;
433 int maskallows = -1; /* true, but not 1, either */
434 int seen_userobj = 0;
435
436 matched.ae_tag = 0; /* Invalid type */
Christoph Hellwig5bde1ba92005-11-02 15:06:18 +1100437 matched.ae_perm = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438 md >>= 6; /* Normalize the bits for comparison */
439
440 for (i = 0; i < fap->acl_cnt; i++) {
441 /*
442 * Break out if we've got a user_obj entry or
443 * a user entry and the mask (and have processed USER_OBJ)
444 */
445 if (matched.ae_tag == ACL_USER_OBJ)
446 break;
447 if (matched.ae_tag == ACL_USER) {
448 if (maskallows != -1 && seen_userobj)
449 break;
450 if (fap->acl_entry[i].ae_tag != ACL_MASK &&
451 fap->acl_entry[i].ae_tag != ACL_USER_OBJ)
452 continue;
453 }
454 /* True if this entry allows the requested access */
455 allows = ((fap->acl_entry[i].ae_perm & md) == md);
456
457 switch (fap->acl_entry[i].ae_tag) {
458 case ACL_USER_OBJ:
459 seen_userobj = 1;
460 if (fuid != current->fsuid)
461 continue;
462 matched.ae_tag = ACL_USER_OBJ;
463 matched.ae_perm = allows;
464 break;
465 case ACL_USER:
466 if (fap->acl_entry[i].ae_id != current->fsuid)
467 continue;
468 matched.ae_tag = ACL_USER;
469 matched.ae_perm = allows;
470 break;
471 case ACL_GROUP_OBJ:
472 if ((matched.ae_tag == ACL_GROUP_OBJ ||
473 matched.ae_tag == ACL_GROUP) && !allows)
474 continue;
475 if (!in_group_p(fgid))
476 continue;
477 matched.ae_tag = ACL_GROUP_OBJ;
478 matched.ae_perm = allows;
479 break;
480 case ACL_GROUP:
481 if ((matched.ae_tag == ACL_GROUP_OBJ ||
482 matched.ae_tag == ACL_GROUP) && !allows)
483 continue;
484 if (!in_group_p(fap->acl_entry[i].ae_id))
485 continue;
486 matched.ae_tag = ACL_GROUP;
487 matched.ae_perm = allows;
488 break;
489 case ACL_MASK:
490 maskallows = allows;
491 break;
492 case ACL_OTHER:
493 if (matched.ae_tag != 0)
494 continue;
495 matched.ae_tag = ACL_OTHER;
496 matched.ae_perm = allows;
497 break;
498 }
499 }
500 /*
501 * First possibility is that no matched entry allows access.
502 * The capability to override DAC may exist, so check for it.
503 */
504 switch (matched.ae_tag) {
505 case ACL_OTHER:
506 case ACL_USER_OBJ:
507 if (matched.ae_perm)
508 return 0;
509 break;
510 case ACL_USER:
511 case ACL_GROUP_OBJ:
512 case ACL_GROUP:
513 if (maskallows && matched.ae_perm)
514 return 0;
515 break;
516 case 0:
517 break;
518 }
519
520 return xfs_acl_capability_check(md, cr);
521}
522
523/*
524 * ACL validity checker.
525 * This acl validation routine checks each ACL entry read in makes sense.
526 */
527STATIC int
528xfs_acl_invalid(
529 xfs_acl_t *aclp)
530{
531 xfs_acl_entry_t *entry, *e;
532 int user = 0, group = 0, other = 0, mask = 0;
533 int mask_required = 0;
534 int i, j;
535
536 if (!aclp)
537 goto acl_invalid;
538
539 if (aclp->acl_cnt > XFS_ACL_MAX_ENTRIES)
540 goto acl_invalid;
541
542 for (i = 0; i < aclp->acl_cnt; i++) {
543 entry = &aclp->acl_entry[i];
544 switch (entry->ae_tag) {
545 case ACL_USER_OBJ:
546 if (user++)
547 goto acl_invalid;
548 break;
549 case ACL_GROUP_OBJ:
550 if (group++)
551 goto acl_invalid;
552 break;
553 case ACL_OTHER:
554 if (other++)
555 goto acl_invalid;
556 break;
557 case ACL_USER:
558 case ACL_GROUP:
559 for (j = i + 1; j < aclp->acl_cnt; j++) {
560 e = &aclp->acl_entry[j];
561 if (e->ae_id == entry->ae_id &&
562 e->ae_tag == entry->ae_tag)
563 goto acl_invalid;
564 }
565 mask_required++;
566 break;
567 case ACL_MASK:
568 if (mask++)
569 goto acl_invalid;
570 break;
571 default:
572 goto acl_invalid;
573 }
574 }
575 if (!user || !group || !other || (mask_required && !mask))
576 goto acl_invalid;
577 else
578 return 0;
579acl_invalid:
580 return EINVAL;
581}
582
583/*
584 * Do ACL endian conversion.
585 */
586STATIC void
587xfs_acl_get_endian(
588 xfs_acl_t *aclp)
589{
590 xfs_acl_entry_t *ace, *end;
591
592 INT_SET(aclp->acl_cnt, ARCH_CONVERT, aclp->acl_cnt);
593 end = &aclp->acl_entry[0]+aclp->acl_cnt;
594 for (ace = &aclp->acl_entry[0]; ace < end; ace++) {
595 INT_SET(ace->ae_tag, ARCH_CONVERT, ace->ae_tag);
596 INT_SET(ace->ae_id, ARCH_CONVERT, ace->ae_id);
597 INT_SET(ace->ae_perm, ARCH_CONVERT, ace->ae_perm);
598 }
599}
600
601/*
602 * Get the ACL from the EA and do endian conversion.
603 */
604STATIC void
605xfs_acl_get_attr(
Nathan Scott67fcaa72006-06-09 17:00:52 +1000606 bhv_vnode_t *vp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 xfs_acl_t *aclp,
608 int kind,
609 int flags,
610 int *error)
611{
612 int len = sizeof(xfs_acl_t);
613
614 ASSERT((flags & ATTR_KERNOVAL) ? (aclp == NULL) : 1);
615 flags |= ATTR_ROOT;
Nathan Scott67fcaa72006-06-09 17:00:52 +1000616 *error = bhv_vop_attr_get(vp, kind == _ACL_TYPE_ACCESS ?
617 SGI_ACL_FILE : SGI_ACL_DEFAULT,
618 (char *)aclp, &len, flags, sys_cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619 if (*error || (flags & ATTR_KERNOVAL))
620 return;
621 xfs_acl_get_endian(aclp);
622}
623
624/*
625 * Set the EA with the ACL and do endian conversion.
626 */
627STATIC void
628xfs_acl_set_attr(
Nathan Scott67fcaa72006-06-09 17:00:52 +1000629 bhv_vnode_t *vp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 xfs_acl_t *aclp,
631 int kind,
632 int *error)
633{
634 xfs_acl_entry_t *ace, *newace, *end;
635 xfs_acl_t *newacl;
636 int len;
637
638 if (!(_ACL_ALLOC(newacl))) {
639 *error = ENOMEM;
640 return;
641 }
642
643 len = sizeof(xfs_acl_t) -
644 (sizeof(xfs_acl_entry_t) * (XFS_ACL_MAX_ENTRIES - aclp->acl_cnt));
645 end = &aclp->acl_entry[0]+aclp->acl_cnt;
646 for (ace = &aclp->acl_entry[0], newace = &newacl->acl_entry[0];
647 ace < end;
648 ace++, newace++) {
649 INT_SET(newace->ae_tag, ARCH_CONVERT, ace->ae_tag);
650 INT_SET(newace->ae_id, ARCH_CONVERT, ace->ae_id);
651 INT_SET(newace->ae_perm, ARCH_CONVERT, ace->ae_perm);
652 }
653 INT_SET(newacl->acl_cnt, ARCH_CONVERT, aclp->acl_cnt);
Nathan Scott67fcaa72006-06-09 17:00:52 +1000654 *error = bhv_vop_attr_set(vp, kind == _ACL_TYPE_ACCESS ?
655 SGI_ACL_FILE: SGI_ACL_DEFAULT,
656 (char *)newacl, len, ATTR_ROOT, sys_cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 _ACL_FREE(newacl);
658}
659
660int
661xfs_acl_vtoacl(
Nathan Scott67fcaa72006-06-09 17:00:52 +1000662 bhv_vnode_t *vp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 xfs_acl_t *access_acl,
664 xfs_acl_t *default_acl)
665{
Nathan Scott8285fb52006-06-09 17:07:12 +1000666 bhv_vattr_t va;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 int error = 0;
668
669 if (access_acl) {
670 /*
671 * Get the Access ACL and the mode. If either cannot
672 * be obtained for some reason, invalidate the access ACL.
673 */
674 xfs_acl_get_attr(vp, access_acl, _ACL_TYPE_ACCESS, 0, &error);
675 if (!error) {
676 /* Got the ACL, need the mode... */
677 va.va_mask = XFS_AT_MODE;
Nathan Scott67fcaa72006-06-09 17:00:52 +1000678 error = bhv_vop_getattr(vp, &va, 0, sys_cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679 }
680
681 if (error)
682 access_acl->acl_cnt = XFS_ACL_NOT_PRESENT;
683 else /* We have a good ACL and the file mode, synchronize. */
684 xfs_acl_sync_mode(va.va_mode, access_acl);
685 }
686
687 if (default_acl) {
688 xfs_acl_get_attr(vp, default_acl, _ACL_TYPE_DEFAULT, 0, &error);
689 if (error)
690 default_acl->acl_cnt = XFS_ACL_NOT_PRESENT;
691 }
692 return error;
693}
694
695/*
696 * This function retrieves the parent directory's acl, processes it
697 * and lets the child inherit the acl(s) that it should.
698 */
699int
700xfs_acl_inherit(
Nathan Scott67fcaa72006-06-09 17:00:52 +1000701 bhv_vnode_t *vp,
Nathan Scott8285fb52006-06-09 17:07:12 +1000702 bhv_vattr_t *vap,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 xfs_acl_t *pdaclp)
704{
705 xfs_acl_t *cacl;
706 int error = 0;
707 int basicperms = 0;
708
709 /*
710 * If the parent does not have a default ACL, or it's an
711 * invalid ACL, we're done.
712 */
713 if (!vp)
714 return 0;
715 if (!pdaclp || xfs_acl_invalid(pdaclp))
716 return 0;
717
718 /*
719 * Copy the default ACL of the containing directory to
720 * the access ACL of the new file and use the mode that
721 * was passed in to set up the correct initial values for
722 * the u::,g::[m::], and o:: entries. This is what makes
723 * umask() "work" with ACL's.
724 */
725
726 if (!(_ACL_ALLOC(cacl)))
727 return ENOMEM;
728
729 memcpy(cacl, pdaclp, sizeof(xfs_acl_t));
730 xfs_acl_filter_mode(vap->va_mode, cacl);
731 xfs_acl_setmode(vp, cacl, &basicperms);
732
733 /*
734 * Set the Default and Access ACL on the file. The mode is already
735 * set on the file, so we don't need to worry about that.
736 *
737 * If the new file is a directory, its default ACL is a copy of
738 * the containing directory's default ACL.
739 */
Christoph Hellwig0432dab2005-09-02 16:46:51 +1000740 if (VN_ISDIR(vp))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741 xfs_acl_set_attr(vp, pdaclp, _ACL_TYPE_DEFAULT, &error);
742 if (!error && !basicperms)
743 xfs_acl_set_attr(vp, cacl, _ACL_TYPE_ACCESS, &error);
744 _ACL_FREE(cacl);
745 return error;
746}
747
748/*
749 * Set up the correct mode on the file based on the supplied ACL. This
750 * makes sure that the mode on the file reflects the state of the
751 * u::,g::[m::], and o:: entries in the ACL. Since the mode is where
752 * the ACL is going to get the permissions for these entries, we must
753 * synchronize the mode whenever we set the ACL on a file.
754 */
755STATIC int
756xfs_acl_setmode(
Nathan Scott67fcaa72006-06-09 17:00:52 +1000757 bhv_vnode_t *vp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758 xfs_acl_t *acl,
759 int *basicperms)
760{
Nathan Scott8285fb52006-06-09 17:07:12 +1000761 bhv_vattr_t va;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762 xfs_acl_entry_t *ap;
763 xfs_acl_entry_t *gap = NULL;
764 int i, error, nomask = 1;
765
766 *basicperms = 1;
767
768 if (acl->acl_cnt == XFS_ACL_NOT_PRESENT)
769 return 0;
770
771 /*
772 * Copy the u::, g::, o::, and m:: bits from the ACL into the
773 * mode. The m:: bits take precedence over the g:: bits.
774 */
775 va.va_mask = XFS_AT_MODE;
Nathan Scott67fcaa72006-06-09 17:00:52 +1000776 error = bhv_vop_getattr(vp, &va, 0, sys_cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777 if (error)
778 return error;
779
780 va.va_mask = XFS_AT_MODE;
781 va.va_mode &= ~(S_IRWXU|S_IRWXG|S_IRWXO);
782 ap = acl->acl_entry;
783 for (i = 0; i < acl->acl_cnt; ++i) {
784 switch (ap->ae_tag) {
785 case ACL_USER_OBJ:
786 va.va_mode |= ap->ae_perm << 6;
787 break;
788 case ACL_GROUP_OBJ:
789 gap = ap;
790 break;
791 case ACL_MASK: /* more than just standard modes */
792 nomask = 0;
793 va.va_mode |= ap->ae_perm << 3;
794 *basicperms = 0;
795 break;
796 case ACL_OTHER:
797 va.va_mode |= ap->ae_perm;
798 break;
799 default: /* more than just standard modes */
800 *basicperms = 0;
801 break;
802 }
803 ap++;
804 }
805
806 /* Set the group bits from ACL_GROUP_OBJ if there's no ACL_MASK */
807 if (gap && nomask)
808 va.va_mode |= gap->ae_perm << 3;
809
Nathan Scott67fcaa72006-06-09 17:00:52 +1000810 return bhv_vop_setattr(vp, &va, 0, sys_cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700811}
812
813/*
814 * The permissions for the special ACL entries (u::, g::[m::], o::) are
815 * actually stored in the file mode (if there is both a group and a mask,
816 * the group is stored in the ACL entry and the mask is stored on the file).
817 * This allows the mode to remain automatically in sync with the ACL without
818 * the need for a call-back to the ACL system at every point where the mode
819 * could change. This function takes the permissions from the specified mode
820 * and places it in the supplied ACL.
821 *
822 * This implementation draws its validity from the fact that, when the ACL
823 * was assigned, the mode was copied from the ACL.
824 * If the mode did not change, therefore, the mode remains exactly what was
825 * taken from the special ACL entries at assignment.
826 * If a subsequent chmod() was done, the POSIX spec says that the change in
827 * mode must cause an update to the ACL seen at user level and used for
828 * access checks. Before and after a mode change, therefore, the file mode
829 * most accurately reflects what the special ACL entries should permit/deny.
830 *
831 * CAVEAT: If someone sets the SGI_ACL_FILE attribute directly,
832 * the existing mode bits will override whatever is in the
833 * ACL. Similarly, if there is a pre-existing ACL that was
834 * never in sync with its mode (owing to a bug in 6.5 and
835 * before), it will now magically (or mystically) be
836 * synchronized. This could cause slight astonishment, but
837 * it is better than inconsistent permissions.
838 *
839 * The supplied ACL is a template that may contain any combination
840 * of special entries. These are treated as place holders when we fill
841 * out the ACL. This routine does not add or remove special entries, it
842 * simply unites each special entry with its associated set of permissions.
843 */
844STATIC void
845xfs_acl_sync_mode(
846 mode_t mode,
847 xfs_acl_t *acl)
848{
849 int i, nomask = 1;
850 xfs_acl_entry_t *ap;
851 xfs_acl_entry_t *gap = NULL;
852
853 /*
854 * Set ACL entries. POSIX1003.1eD16 requires that the MASK
855 * be set instead of the GROUP entry, if there is a MASK.
856 */
857 for (ap = acl->acl_entry, i = 0; i < acl->acl_cnt; ap++, i++) {
858 switch (ap->ae_tag) {
859 case ACL_USER_OBJ:
860 ap->ae_perm = (mode >> 6) & 0x7;
861 break;
862 case ACL_GROUP_OBJ:
863 gap = ap;
864 break;
865 case ACL_MASK:
866 nomask = 0;
867 ap->ae_perm = (mode >> 3) & 0x7;
868 break;
869 case ACL_OTHER:
870 ap->ae_perm = mode & 0x7;
871 break;
872 default:
873 break;
874 }
875 }
876 /* Set the ACL_GROUP_OBJ if there's no ACL_MASK */
877 if (gap && nomask)
878 gap->ae_perm = (mode >> 3) & 0x7;
879}
880
881/*
882 * When inheriting an Access ACL from a directory Default ACL,
883 * the ACL bits are set to the intersection of the ACL default
884 * permission bits and the file permission bits in mode. If there
885 * are no permission bits on the file then we must not give them
886 * the ACL. This is what what makes umask() work with ACLs.
887 */
888STATIC void
889xfs_acl_filter_mode(
890 mode_t mode,
891 xfs_acl_t *acl)
892{
893 int i, nomask = 1;
894 xfs_acl_entry_t *ap;
895 xfs_acl_entry_t *gap = NULL;
896
897 /*
898 * Set ACL entries. POSIX1003.1eD16 requires that the MASK
899 * be merged with GROUP entry, if there is a MASK.
900 */
901 for (ap = acl->acl_entry, i = 0; i < acl->acl_cnt; ap++, i++) {
902 switch (ap->ae_tag) {
903 case ACL_USER_OBJ:
904 ap->ae_perm &= (mode >> 6) & 0x7;
905 break;
906 case ACL_GROUP_OBJ:
907 gap = ap;
908 break;
909 case ACL_MASK:
910 nomask = 0;
911 ap->ae_perm &= (mode >> 3) & 0x7;
912 break;
913 case ACL_OTHER:
914 ap->ae_perm &= mode & 0x7;
915 break;
916 default:
917 break;
918 }
919 }
920 /* Set the ACL_GROUP_OBJ if there's no ACL_MASK */
921 if (gap && nomask)
922 gap->ae_perm &= (mode >> 3) & 0x7;
923}