?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Avoid beyond bounds copy while caching ACL
[zen-stable.git] / fs / cifs / cifsacl.c
blobc1b254487388ab3a23ce4af9d1226e84a7ead901
1 /*
2 * fs/cifs/cifsacl.c
3 *
4 * Copyright (C) International Business Machines Corp., 2007,2008
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 * Contains the routines for mapping CIFS/NTFS ACLs
8 *
9 * This library is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU Lesser General Public License as published
11 * by the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
13 *
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
17 * the GNU Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this library; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23
24 #include <linux/fs.h>
25 #include <linux/slab.h>
26 #include <linux/string.h>
27 #include <linux/keyctl.h>
28 #include <linux/key-type.h>
29 #include <keys/user-type.h>
30 #include "cifspdu.h"
31 #include "cifsglob.h"
32 #include "cifsacl.h"
33 #include "cifsproto.h"
34 #include "cifs_debug.h"
35
36 /* security id for everyone/world system group */
37 static const struct cifs_sid sid_everyone = {
38 1, 1, {0, 0, 0, 0, 0, 1}, {0} };
39 /* security id for Authenticated Users system group */
40 static const struct cifs_sid sid_authusers = {
41 1, 1, {0, 0, 0, 0, 0, 5}, {__constant_cpu_to_le32(11)} };
42 /* group users */
43 static const struct cifs_sid sid_user = {1, 2 , {0, 0, 0, 0, 0, 5}, {} };
44
45 const struct cred *root_cred;
46
47 static void
48 shrink_idmap_tree(struct rb_root *root, int nr_to_scan, int *nr_rem,
49 int *nr_del)
50 {
51 struct rb_node *node;
52 struct rb_node *tmp;
53 struct cifs_sid_id *psidid;
54
55 node = rb_first(root);
56 while (node) {
57 tmp = node;
58 node = rb_next(tmp);
59 psidid = rb_entry(tmp, struct cifs_sid_id, rbnode);
60 if (nr_to_scan == 0 || *nr_del == nr_to_scan)
61 ++(*nr_rem);
62 else {
63 if (time_after(jiffies, psidid->time + SID_MAP_EXPIRE)
64 && psidid->refcount == 0) {
65 rb_erase(tmp, root);
66 ++(*nr_del);
67 } else
68 ++(*nr_rem);
69 }
70 }
71 }
72
73 /*
74 * Run idmap cache shrinker.
75 */
76 static int
77 cifs_idmap_shrinker(struct shrinker *shrink, struct shrink_control *sc)
78 {
79 int nr_to_scan = sc->nr_to_scan;
80 int nr_del = 0;
81 int nr_rem = 0;
82 struct rb_root *root;
83
84 root = &uidtree;
85 spin_lock(&siduidlock);
86 shrink_idmap_tree(root, nr_to_scan, &nr_rem, &nr_del);
87 spin_unlock(&siduidlock);
88
89 root = &gidtree;
90 spin_lock(&sidgidlock);
91 shrink_idmap_tree(root, nr_to_scan, &nr_rem, &nr_del);
92 spin_unlock(&sidgidlock);
93
94 root = &siduidtree;
95 spin_lock(&uidsidlock);
96 shrink_idmap_tree(root, nr_to_scan, &nr_rem, &nr_del);
97 spin_unlock(&uidsidlock);
98
99 root = &sidgidtree;
100 spin_lock(&gidsidlock);
101 shrink_idmap_tree(root, nr_to_scan, &nr_rem, &nr_del);
102 spin_unlock(&gidsidlock);
103
104 return nr_rem;
105 }
106
107 static void
108 sid_rb_insert(struct rb_root *root, unsigned long cid,
109 struct cifs_sid_id **psidid, char *typestr)
110 {
111 char *strptr;
112 struct rb_node *node = root->rb_node;
113 struct rb_node *parent = NULL;
114 struct rb_node **linkto = &(root->rb_node);
115 struct cifs_sid_id *lsidid;
116
117 while (node) {
118 lsidid = rb_entry(node, struct cifs_sid_id, rbnode);
119 parent = node;
120 if (cid > lsidid->id) {
121 linkto = &(node->rb_left);
122 node = node->rb_left;
123 }
124 if (cid < lsidid->id) {
125 linkto = &(node->rb_right);
126 node = node->rb_right;
127 }
128 }
129
130 (*psidid)->id = cid;
131 (*psidid)->time = jiffies - (SID_MAP_RETRY + 1);
132 (*psidid)->refcount = 0;
133
134 sprintf((*psidid)->sidstr, "%s", typestr);
135 strptr = (*psidid)->sidstr + strlen((*psidid)->sidstr);
136 sprintf(strptr, "%ld", cid);
137
138 clear_bit(SID_ID_PENDING, &(*psidid)->state);
139 clear_bit(SID_ID_MAPPED, &(*psidid)->state);
140
141 rb_link_node(&(*psidid)->rbnode, parent, linkto);
142 rb_insert_color(&(*psidid)->rbnode, root);
143 }
144
145 static struct cifs_sid_id *
146 sid_rb_search(struct rb_root *root, unsigned long cid)
147 {
148 struct rb_node *node = root->rb_node;
149 struct cifs_sid_id *lsidid;
150
151 while (node) {
152 lsidid = rb_entry(node, struct cifs_sid_id, rbnode);
153 if (cid > lsidid->id)
154 node = node->rb_left;
155 else if (cid < lsidid->id)
156 node = node->rb_right;
157 else /* node found */
158 return lsidid;
159 }
160
161 return NULL;
162 }
163
164 static struct shrinker cifs_shrinker = {
165 .shrink = cifs_idmap_shrinker,
166 .seeks = DEFAULT_SEEKS,
167 };
168
169 static int
170 cifs_idmap_key_instantiate(struct key *key, const void *data, size_t datalen)
171 {
172 char *payload;
173
174 payload = kmalloc(datalen, GFP_KERNEL);
175 if (!payload)
176 return -ENOMEM;
177
178 memcpy(payload, data, datalen);
179 key->payload.data = payload;
180 key->datalen = datalen;
181 return 0;
182 }
183
184 static inline void
185 cifs_idmap_key_destroy(struct key *key)
186 {
187 kfree(key->payload.data);
188 }
189
190 struct key_type cifs_idmap_key_type = {
191 .name = "cifs.idmap",
192 .instantiate = cifs_idmap_key_instantiate,
193 .destroy = cifs_idmap_key_destroy,
194 .describe = user_describe,
195 .match = user_match,
196 };
197
198 static void
199 sid_to_str(struct cifs_sid *sidptr, char *sidstr)
200 {
201 int i;
202 unsigned long saval;
203 char *strptr;
204
205 strptr = sidstr;
206
207 sprintf(strptr, "%s", "S");
208 strptr = sidstr + strlen(sidstr);
209
210 sprintf(strptr, "-%d", sidptr->revision);
211 strptr = sidstr + strlen(sidstr);
212
213 for (i = 0; i < 6; ++i) {
214 if (sidptr->authority[i]) {
215 sprintf(strptr, "-%d", sidptr->authority[i]);
216 strptr = sidstr + strlen(sidstr);
217 }
218 }
219
220 for (i = 0; i < sidptr->num_subauth; ++i) {
221 saval = le32_to_cpu(sidptr->sub_auth[i]);
222 sprintf(strptr, "-%ld", saval);
223 strptr = sidstr + strlen(sidstr);
224 }
225 }
226
227 static void
228 id_rb_insert(struct rb_root *root, struct cifs_sid *sidptr,
229 struct cifs_sid_id **psidid, char *typestr)
230 {
231 int rc;
232 char *strptr;
233 struct rb_node *node = root->rb_node;
234 struct rb_node *parent = NULL;
235 struct rb_node **linkto = &(root->rb_node);
236 struct cifs_sid_id *lsidid;
237
238 while (node) {
239 lsidid = rb_entry(node, struct cifs_sid_id, rbnode);
240 parent = node;
241 rc = compare_sids(sidptr, &((lsidid)->sid));
242 if (rc > 0) {
243 linkto = &(node->rb_left);
244 node = node->rb_left;
245 } else if (rc < 0) {
246 linkto = &(node->rb_right);
247 node = node->rb_right;
248 }
249 }
250
251 memcpy(&(*psidid)->sid, sidptr, sizeof(struct cifs_sid));
252 (*psidid)->time = jiffies - (SID_MAP_RETRY + 1);
253 (*psidid)->refcount = 0;
254
255 sprintf((*psidid)->sidstr, "%s", typestr);
256 strptr = (*psidid)->sidstr + strlen((*psidid)->sidstr);
257 sid_to_str(&(*psidid)->sid, strptr);
258
259 clear_bit(SID_ID_PENDING, &(*psidid)->state);
260 clear_bit(SID_ID_MAPPED, &(*psidid)->state);
261
262 rb_link_node(&(*psidid)->rbnode, parent, linkto);
263 rb_insert_color(&(*psidid)->rbnode, root);
264 }
265
266 static struct cifs_sid_id *
267 id_rb_search(struct rb_root *root, struct cifs_sid *sidptr)
268 {
269 int rc;
270 struct rb_node *node = root->rb_node;
271 struct cifs_sid_id *lsidid;
272
273 while (node) {
274 lsidid = rb_entry(node, struct cifs_sid_id, rbnode);
275 rc = compare_sids(sidptr, &((lsidid)->sid));
276 if (rc > 0) {
277 node = node->rb_left;
278 } else if (rc < 0) {
279 node = node->rb_right;
280 } else /* node found */
281 return lsidid;
282 }
283
284 return NULL;
285 }
286
287 static int
288 sidid_pending_wait(void *unused)
289 {
290 schedule();
291 return signal_pending(current) ? -ERESTARTSYS : 0;
292 }
293
294 static int
295 id_to_sid(unsigned long cid, uint sidtype, struct cifs_sid *ssid)
296 {
297 int rc = 0;
298 struct key *sidkey;
299 const struct cred *saved_cred;
300 struct cifs_sid *lsid;
301 struct cifs_sid_id *psidid, *npsidid;
302 struct rb_root *cidtree;
303 spinlock_t *cidlock;
304
305 if (sidtype == SIDOWNER) {
306 cidlock = &siduidlock;
307 cidtree = &uidtree;
308 } else if (sidtype == SIDGROUP) {
309 cidlock = &sidgidlock;
310 cidtree = &gidtree;
311 } else
312 return -EINVAL;
313
314 spin_lock(cidlock);
315 psidid = sid_rb_search(cidtree, cid);
316
317 if (!psidid) { /* node does not exist, allocate one & attempt adding */
318 spin_unlock(cidlock);
319 npsidid = kzalloc(sizeof(struct cifs_sid_id), GFP_KERNEL);
320 if (!npsidid)
321 return -ENOMEM;
322
323 npsidid->sidstr = kmalloc(SIDLEN, GFP_KERNEL);
324 if (!npsidid->sidstr) {
325 kfree(npsidid);
326 return -ENOMEM;
327 }
328
329 spin_lock(cidlock);
330 psidid = sid_rb_search(cidtree, cid);
331 if (psidid) { /* node happened to get inserted meanwhile */
332 ++psidid->refcount;
333 spin_unlock(cidlock);
334 kfree(npsidid->sidstr);
335 kfree(npsidid);
336 } else {
337 psidid = npsidid;
338 sid_rb_insert(cidtree, cid, &psidid,
339 sidtype == SIDOWNER ? "oi:" : "gi:");
340 ++psidid->refcount;
341 spin_unlock(cidlock);
342 }
343 } else {
344 ++psidid->refcount;
345 spin_unlock(cidlock);
346 }
347
348 /*
349 * If we are here, it is safe to access psidid and its fields
350 * since a reference was taken earlier while holding the spinlock.
351 * A reference on the node is put without holding the spinlock
352 * and it is OK to do so in this case, shrinker will not erase
353 * this node until all references are put and we do not access
354 * any fields of the node after a reference is put .
355 */
356 if (test_bit(SID_ID_MAPPED, &psidid->state)) {
357 memcpy(ssid, &psidid->sid, sizeof(struct cifs_sid));
358 psidid->time = jiffies; /* update ts for accessing */
359 goto id_sid_out;
360 }
361
362 if (time_after(psidid->time + SID_MAP_RETRY, jiffies)) {
363 rc = -EINVAL;
364 goto id_sid_out;
365 }
366
367 if (!test_and_set_bit(SID_ID_PENDING, &psidid->state)) {
368 saved_cred = override_creds(root_cred);
369 sidkey = request_key(&cifs_idmap_key_type, psidid->sidstr, "");
370 if (IS_ERR(sidkey)) {
371 rc = -EINVAL;
372 cFYI(1, "%s: Can't map and id to a SID", __func__);
373 } else {
374 lsid = (struct cifs_sid *)sidkey->payload.data;
375 memcpy(&psidid->sid, lsid,
376 sidkey->datalen < sizeof(struct cifs_sid) ?
377 sidkey->datalen : sizeof(struct cifs_sid));
378 memcpy(ssid, &psidid->sid,
379 sidkey->datalen < sizeof(struct cifs_sid) ?
380 sidkey->datalen : sizeof(struct cifs_sid));
381 set_bit(SID_ID_MAPPED, &psidid->state);
382 key_put(sidkey);
383 kfree(psidid->sidstr);
384 }
385 psidid->time = jiffies; /* update ts for accessing */
386 revert_creds(saved_cred);
387 clear_bit(SID_ID_PENDING, &psidid->state);
388 wake_up_bit(&psidid->state, SID_ID_PENDING);
389 } else {
390 rc = wait_on_bit(&psidid->state, SID_ID_PENDING,
391 sidid_pending_wait, TASK_INTERRUPTIBLE);
392 if (rc) {
393 cFYI(1, "%s: sidid_pending_wait interrupted %d",
394 __func__, rc);
395 --psidid->refcount;
396 return rc;
397 }
398 if (test_bit(SID_ID_MAPPED, &psidid->state))
399 memcpy(ssid, &psidid->sid, sizeof(struct cifs_sid));
400 else
401 rc = -EINVAL;
402 }
403 id_sid_out:
404 --psidid->refcount;
405 return rc;
406 }
407
408 static int
409 sid_to_id(struct cifs_sb_info *cifs_sb, struct cifs_sid *psid,
410 struct cifs_fattr *fattr, uint sidtype)
411 {
412 int rc;
413 unsigned long cid;
414 struct key *idkey;
415 const struct cred *saved_cred;
416 struct cifs_sid_id *psidid, *npsidid;
417 struct rb_root *cidtree;
418 spinlock_t *cidlock;
419
420 if (sidtype == SIDOWNER) {
421 cid = cifs_sb->mnt_uid; /* default uid, in case upcall fails */
422 cidlock = &siduidlock;
423 cidtree = &uidtree;
424 } else if (sidtype == SIDGROUP) {
425 cid = cifs_sb->mnt_gid; /* default gid, in case upcall fails */
426 cidlock = &sidgidlock;
427 cidtree = &gidtree;
428 } else
429 return -ENOENT;
430
431 spin_lock(cidlock);
432 psidid = id_rb_search(cidtree, psid);
433
434 if (!psidid) { /* node does not exist, allocate one & attempt adding */
435 spin_unlock(cidlock);
436 npsidid = kzalloc(sizeof(struct cifs_sid_id), GFP_KERNEL);
437 if (!npsidid)
438 return -ENOMEM;
439
440 npsidid->sidstr = kmalloc(SIDLEN, GFP_KERNEL);
441 if (!npsidid->sidstr) {
442 kfree(npsidid);
443 return -ENOMEM;
444 }
445
446 spin_lock(cidlock);
447 psidid = id_rb_search(cidtree, psid);
448 if (psidid) { /* node happened to get inserted meanwhile */
449 ++psidid->refcount;
450 spin_unlock(cidlock);
451 kfree(npsidid->sidstr);
452 kfree(npsidid);
453 } else {
454 psidid = npsidid;
455 id_rb_insert(cidtree, psid, &psidid,
456 sidtype == SIDOWNER ? "os:" : "gs:");
457 ++psidid->refcount;
458 spin_unlock(cidlock);
459 }
460 } else {
461 ++psidid->refcount;
462 spin_unlock(cidlock);
463 }
464
465 /*
466 * If we are here, it is safe to access psidid and its fields
467 * since a reference was taken earlier while holding the spinlock.
468 * A reference on the node is put without holding the spinlock
469 * and it is OK to do so in this case, shrinker will not erase
470 * this node until all references are put and we do not access
471 * any fields of the node after a reference is put .
472 */
473 if (test_bit(SID_ID_MAPPED, &psidid->state)) {
474 cid = psidid->id;
475 psidid->time = jiffies; /* update ts for accessing */
476 goto sid_to_id_out;
477 }
478
479 if (time_after(psidid->time + SID_MAP_RETRY, jiffies))
480 goto sid_to_id_out;
481
482 if (!test_and_set_bit(SID_ID_PENDING, &psidid->state)) {
483 saved_cred = override_creds(root_cred);
484 idkey = request_key(&cifs_idmap_key_type, psidid->sidstr, "");
485 if (IS_ERR(idkey))
486 cFYI(1, "%s: Can't map SID to an id", __func__);
487 else {
488 cid = *(unsigned long *)idkey->payload.value;
489 psidid->id = cid;
490 set_bit(SID_ID_MAPPED, &psidid->state);
491 key_put(idkey);
492 kfree(psidid->sidstr);
493 }
494 revert_creds(saved_cred);
495 psidid->time = jiffies; /* update ts for accessing */
496 clear_bit(SID_ID_PENDING, &psidid->state);
497 wake_up_bit(&psidid->state, SID_ID_PENDING);
498 } else {
499 rc = wait_on_bit(&psidid->state, SID_ID_PENDING,
500 sidid_pending_wait, TASK_INTERRUPTIBLE);
501 if (rc) {
502 cFYI(1, "%s: sidid_pending_wait interrupted %d",
503 __func__, rc);
504 --psidid->refcount; /* decremented without spinlock */
505 return rc;
506 }
507 if (test_bit(SID_ID_MAPPED, &psidid->state))
508 cid = psidid->id;
509 }
510
511 sid_to_id_out:
512 --psidid->refcount; /* decremented without spinlock */
513 if (sidtype == SIDOWNER)
514 fattr->cf_uid = cid;
515 else
516 fattr->cf_gid = cid;
517
518 return 0;
519 }
520
521 int
522 init_cifs_idmap(void)
523 {
524 struct cred *cred;
525 struct key *keyring;
526 int ret;
527
528 cFYI(1, "Registering the %s key type\n", cifs_idmap_key_type.name);
529
530 /* create an override credential set with a special thread keyring in
531 * which requests are cached
532 *
533 * this is used to prevent malicious redirections from being installed
534 * with add_key().
535 */
536 cred = prepare_kernel_cred(NULL);
537 if (!cred)
538 return -ENOMEM;
539
540 keyring = key_alloc(&key_type_keyring, ".cifs_idmap", 0, 0, cred,
541 (KEY_POS_ALL & ~KEY_POS_SETATTR) |
542 KEY_USR_VIEW | KEY_USR_READ,
543 KEY_ALLOC_NOT_IN_QUOTA);
544 if (IS_ERR(keyring)) {
545 ret = PTR_ERR(keyring);
546 goto failed_put_cred;
547 }
548
549 ret = key_instantiate_and_link(keyring, NULL, 0, NULL, NULL);
550 if (ret < 0)
551 goto failed_put_key;
552
553 ret = register_key_type(&cifs_idmap_key_type);
554 if (ret < 0)
555 goto failed_put_key;
556
557 /* instruct request_key() to use this special keyring as a cache for
558 * the results it looks up */
559 cred->thread_keyring = keyring;
560 cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
561 root_cred = cred;
562
563 spin_lock_init(&siduidlock);
564 uidtree = RB_ROOT;
565 spin_lock_init(&sidgidlock);
566 gidtree = RB_ROOT;
567
568 spin_lock_init(&uidsidlock);
569 siduidtree = RB_ROOT;
570 spin_lock_init(&gidsidlock);
571 sidgidtree = RB_ROOT;
572 register_shrinker(&cifs_shrinker);
573
574 cFYI(1, "cifs idmap keyring: %d\n", key_serial(keyring));
575 return 0;
576
577 failed_put_key:
578 key_put(keyring);
579 failed_put_cred:
580 put_cred(cred);
581 return ret;
582 }
583
584 void
585 exit_cifs_idmap(void)
586 {
587 key_revoke(root_cred->thread_keyring);
588 unregister_key_type(&cifs_idmap_key_type);
589 put_cred(root_cred);
590 unregister_shrinker(&cifs_shrinker);
591 cFYI(1, "Unregistered %s key type\n", cifs_idmap_key_type.name);
592 }
593
594 void
595 cifs_destroy_idmaptrees(void)
596 {
597 struct rb_root *root;
598 struct rb_node *node;
599
600 root = &uidtree;
601 spin_lock(&siduidlock);
602 while ((node = rb_first(root)))
603 rb_erase(node, root);
604 spin_unlock(&siduidlock);
605
606 root = &gidtree;
607 spin_lock(&sidgidlock);
608 while ((node = rb_first(root)))
609 rb_erase(node, root);
610 spin_unlock(&sidgidlock);
611
612 root = &siduidtree;
613 spin_lock(&uidsidlock);
614 while ((node = rb_first(root)))
615 rb_erase(node, root);
616 spin_unlock(&uidsidlock);
617
618 root = &sidgidtree;
619 spin_lock(&gidsidlock);
620 while ((node = rb_first(root)))
621 rb_erase(node, root);
622 spin_unlock(&gidsidlock);
623 }
624
625 /* if the two SIDs (roughly equivalent to a UUID for a user or group) are
626 the same returns 1, if they do not match returns 0 */
627 int compare_sids(const struct cifs_sid *ctsid, const struct cifs_sid *cwsid)
628 {
629 int i;
630 int num_subauth, num_sat, num_saw;
631
632 if ((!ctsid) || (!cwsid))
633 return 1;
634
635 /* compare the revision */
636 if (ctsid->revision != cwsid->revision) {
637 if (ctsid->revision > cwsid->revision)
638 return 1;
639 else
640 return -1;
641 }
642
643 /* compare all of the six auth values */
644 for (i = 0; i < 6; ++i) {
645 if (ctsid->authority[i] != cwsid->authority[i]) {
646 if (ctsid->authority[i] > cwsid->authority[i])
647 return 1;
648 else
649 return -1;
650 }
651 }
652
653 /* compare all of the subauth values if any */
654 num_sat = ctsid->num_subauth;
655 num_saw = cwsid->num_subauth;
656 num_subauth = num_sat < num_saw ? num_sat : num_saw;
657 if (num_subauth) {
658 for (i = 0; i < num_subauth; ++i) {
659 if (ctsid->sub_auth[i] != cwsid->sub_auth[i]) {
660 if (le32_to_cpu(ctsid->sub_auth[i]) >
661 le32_to_cpu(cwsid->sub_auth[i]))
662 return 1;
663 else
664 return -1;
665 }
666 }
667 }
668
669 return 0; /* sids compare/match */
670 }
671
672
673 /* copy ntsd, owner sid, and group sid from a security descriptor to another */
674 static void copy_sec_desc(const struct cifs_ntsd *pntsd,
675 struct cifs_ntsd *pnntsd, __u32 sidsoffset)
676 {
677 int i;
678
679 struct cifs_sid *owner_sid_ptr, *group_sid_ptr;
680 struct cifs_sid *nowner_sid_ptr, *ngroup_sid_ptr;
681
682 /* copy security descriptor control portion */
683 pnntsd->revision = pntsd->revision;
684 pnntsd->type = pntsd->type;
685 pnntsd->dacloffset = cpu_to_le32(sizeof(struct cifs_ntsd));
686 pnntsd->sacloffset = 0;
687 pnntsd->osidoffset = cpu_to_le32(sidsoffset);
688 pnntsd->gsidoffset = cpu_to_le32(sidsoffset + sizeof(struct cifs_sid));
689
690 /* copy owner sid */
691 owner_sid_ptr = (struct cifs_sid *)((char *)pntsd +
692 le32_to_cpu(pntsd->osidoffset));
693 nowner_sid_ptr = (struct cifs_sid *)((char *)pnntsd + sidsoffset);
694
695 nowner_sid_ptr->revision = owner_sid_ptr->revision;
696 nowner_sid_ptr->num_subauth = owner_sid_ptr->num_subauth;
697 for (i = 0; i < 6; i++)
698 nowner_sid_ptr->authority[i] = owner_sid_ptr->authority[i];
699 for (i = 0; i < 5; i++)
700 nowner_sid_ptr->sub_auth[i] = owner_sid_ptr->sub_auth[i];
701
702 /* copy group sid */
703 group_sid_ptr = (struct cifs_sid *)((char *)pntsd +
704 le32_to_cpu(pntsd->gsidoffset));
705 ngroup_sid_ptr = (struct cifs_sid *)((char *)pnntsd + sidsoffset +
706 sizeof(struct cifs_sid));
707
708 ngroup_sid_ptr->revision = group_sid_ptr->revision;
709 ngroup_sid_ptr->num_subauth = group_sid_ptr->num_subauth;
710 for (i = 0; i < 6; i++)
711 ngroup_sid_ptr->authority[i] = group_sid_ptr->authority[i];
712 for (i = 0; i < 5; i++)
713 ngroup_sid_ptr->sub_auth[i] = group_sid_ptr->sub_auth[i];
714
715 return;
716 }
717
718
719 /*
720 change posix mode to reflect permissions
721 pmode is the existing mode (we only want to overwrite part of this
722 bits to set can be: S_IRWXU, S_IRWXG or S_IRWXO ie 00700 or 00070 or 00007
723 */
724 static void access_flags_to_mode(__le32 ace_flags, int type, umode_t *pmode,
725 umode_t *pbits_to_set)
726 {
727 __u32 flags = le32_to_cpu(ace_flags);
728 /* the order of ACEs is important. The canonical order is to begin with
729 DENY entries followed by ALLOW, otherwise an allow entry could be
730 encountered first, making the subsequent deny entry like "dead code"
731 which would be superflous since Windows stops when a match is made
732 for the operation you are trying to perform for your user */
733
734 /* For deny ACEs we change the mask so that subsequent allow access
735 control entries do not turn on the bits we are denying */
736 if (type == ACCESS_DENIED) {
737 if (flags & GENERIC_ALL)
738 *pbits_to_set &= ~S_IRWXUGO;
739
740 if ((flags & GENERIC_WRITE) ||
741 ((flags & FILE_WRITE_RIGHTS) == FILE_WRITE_RIGHTS))
742 *pbits_to_set &= ~S_IWUGO;
743 if ((flags & GENERIC_READ) ||
744 ((flags & FILE_READ_RIGHTS) == FILE_READ_RIGHTS))
745 *pbits_to_set &= ~S_IRUGO;
746 if ((flags & GENERIC_EXECUTE) ||
747 ((flags & FILE_EXEC_RIGHTS) == FILE_EXEC_RIGHTS))
748 *pbits_to_set &= ~S_IXUGO;
749 return;
750 } else if (type != ACCESS_ALLOWED) {
751 cERROR(1, "unknown access control type %d", type);
752 return;
753 }
754 /* else ACCESS_ALLOWED type */
755
756 if (flags & GENERIC_ALL) {
757 *pmode |= (S_IRWXUGO & (*pbits_to_set));
758 cFYI(DBG2, "all perms");
759 return;
760 }
761 if ((flags & GENERIC_WRITE) ||
762 ((flags & FILE_WRITE_RIGHTS) == FILE_WRITE_RIGHTS))
763 *pmode |= (S_IWUGO & (*pbits_to_set));
764 if ((flags & GENERIC_READ) ||
765 ((flags & FILE_READ_RIGHTS) == FILE_READ_RIGHTS))
766 *pmode |= (S_IRUGO & (*pbits_to_set));
767 if ((flags & GENERIC_EXECUTE) ||
768 ((flags & FILE_EXEC_RIGHTS) == FILE_EXEC_RIGHTS))
769 *pmode |= (S_IXUGO & (*pbits_to_set));
770
771 cFYI(DBG2, "access flags 0x%x mode now 0x%x", flags, *pmode);
772 return;
773 }
774
775 /*
776 Generate access flags to reflect permissions mode is the existing mode.
777 This function is called for every ACE in the DACL whose SID matches
778 with either owner or group or everyone.
779 */
780
781 static void mode_to_access_flags(umode_t mode, umode_t bits_to_use,
782 __u32 *pace_flags)
783 {
784 /* reset access mask */
785 *pace_flags = 0x0;
786
787 /* bits to use are either S_IRWXU or S_IRWXG or S_IRWXO */
788 mode &= bits_to_use;
789
790 /* check for R/W/X UGO since we do not know whose flags
791 is this but we have cleared all the bits sans RWX for
792 either user or group or other as per bits_to_use */
793 if (mode & S_IRUGO)
794 *pace_flags |= SET_FILE_READ_RIGHTS;
795 if (mode & S_IWUGO)
796 *pace_flags |= SET_FILE_WRITE_RIGHTS;
797 if (mode & S_IXUGO)
798 *pace_flags |= SET_FILE_EXEC_RIGHTS;
799
800 cFYI(DBG2, "mode: 0x%x, access flags now 0x%x", mode, *pace_flags);
801 return;
802 }
803
804 static __u16 fill_ace_for_sid(struct cifs_ace *pntace,
805 const struct cifs_sid *psid, __u64 nmode, umode_t bits)
806 {
807 int i;
808 __u16 size = 0;
809 __u32 access_req = 0;
810
811 pntace->type = ACCESS_ALLOWED;
812 pntace->flags = 0x0;
813 mode_to_access_flags(nmode, bits, &access_req);
814 if (!access_req)
815 access_req = SET_MINIMUM_RIGHTS;
816 pntace->access_req = cpu_to_le32(access_req);
817
818 pntace->sid.revision = psid->revision;
819 pntace->sid.num_subauth = psid->num_subauth;
820 for (i = 0; i < 6; i++)
821 pntace->sid.authority[i] = psid->authority[i];
822 for (i = 0; i < psid->num_subauth; i++)
823 pntace->sid.sub_auth[i] = psid->sub_auth[i];
824
825 size = 1 + 1 + 2 + 4 + 1 + 1 + 6 + (psid->num_subauth * 4);
826 pntace->size = cpu_to_le16(size);
827
828 return size;
829 }
830
831
832 #ifdef CONFIG_CIFS_DEBUG2
833 static void dump_ace(struct cifs_ace *pace, char *end_of_acl)
834 {
835 int num_subauth;
836
837 /* validate that we do not go past end of acl */
838
839 if (le16_to_cpu(pace->size) < 16) {
840 cERROR(1, "ACE too small %d", le16_to_cpu(pace->size));
841 return;
842 }
843
844 if (end_of_acl < (char *)pace + le16_to_cpu(pace->size)) {
845 cERROR(1, "ACL too small to parse ACE");
846 return;
847 }
848
849 num_subauth = pace->sid.num_subauth;
850 if (num_subauth) {
851 int i;
852 cFYI(1, "ACE revision %d num_auth %d type %d flags %d size %d",
853 pace->sid.revision, pace->sid.num_subauth, pace->type,
854 pace->flags, le16_to_cpu(pace->size));
855 for (i = 0; i < num_subauth; ++i) {
856 cFYI(1, "ACE sub_auth[%d]: 0x%x", i,
857 le32_to_cpu(pace->sid.sub_auth[i]));
858 }
859
860 /* BB add length check to make sure that we do not have huge
861 num auths and therefore go off the end */
862 }
863
864 return;
865 }
866 #endif
867
868
869 static void parse_dacl(struct cifs_acl *pdacl, char *end_of_acl,
870 struct cifs_sid *pownersid, struct cifs_sid *pgrpsid,
871 struct cifs_fattr *fattr)
872 {
873 int i;
874 int num_aces = 0;
875 int acl_size;
876 char *acl_base;
877 struct cifs_ace **ppace;
878
879 /* BB need to add parm so we can store the SID BB */
880
881 if (!pdacl) {
882 /* no DACL in the security descriptor, set
883 all the permissions for user/group/other */
884 fattr->cf_mode |= S_IRWXUGO;
885 return;
886 }
887
888 /* validate that we do not go past end of acl */
889 if (end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) {
890 cERROR(1, "ACL too small to parse DACL");
891 return;
892 }
893
894 cFYI(DBG2, "DACL revision %d size %d num aces %d",
895 le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size),
896 le32_to_cpu(pdacl->num_aces));
897
898 /* reset rwx permissions for user/group/other.
899 Also, if num_aces is 0 i.e. DACL has no ACEs,
900 user/group/other have no permissions */
901 fattr->cf_mode &= ~(S_IRWXUGO);
902
903 acl_base = (char *)pdacl;
904 acl_size = sizeof(struct cifs_acl);
905
906 num_aces = le32_to_cpu(pdacl->num_aces);
907 if (num_aces > 0) {
908 umode_t user_mask = S_IRWXU;
909 umode_t group_mask = S_IRWXG;
910 umode_t other_mask = S_IRWXU | S_IRWXG | S_IRWXO;
911
912 if (num_aces > ULONG_MAX / sizeof(struct cifs_ace *))
913 return;
914 ppace = kmalloc(num_aces * sizeof(struct cifs_ace *),
915 GFP_KERNEL);
916 if (!ppace) {
917 cERROR(1, "DACL memory allocation error");
918 return;
919 }
920
921 for (i = 0; i < num_aces; ++i) {
922 ppace[i] = (struct cifs_ace *) (acl_base + acl_size);
923 #ifdef CONFIG_CIFS_DEBUG2
924 dump_ace(ppace[i], end_of_acl);
925 #endif
926 if (compare_sids(&(ppace[i]->sid), pownersid) == 0)
927 access_flags_to_mode(ppace[i]->access_req,
928 ppace[i]->type,
929 &fattr->cf_mode,
930 &user_mask);
931 if (compare_sids(&(ppace[i]->sid), pgrpsid) == 0)
932 access_flags_to_mode(ppace[i]->access_req,
933 ppace[i]->type,
934 &fattr->cf_mode,
935 &group_mask);
936 if (compare_sids(&(ppace[i]->sid), &sid_everyone) == 0)
937 access_flags_to_mode(ppace[i]->access_req,
938 ppace[i]->type,
939 &fattr->cf_mode,
940 &other_mask);
941 if (compare_sids(&(ppace[i]->sid), &sid_authusers) == 0)
942 access_flags_to_mode(ppace[i]->access_req,
943 ppace[i]->type,
944 &fattr->cf_mode,
945 &other_mask);
946
947
948 /* memcpy((void *)(&(cifscred->aces[i])),
949 (void *)ppace[i],
950 sizeof(struct cifs_ace)); */
951
952 acl_base = (char *)ppace[i];
953 acl_size = le16_to_cpu(ppace[i]->size);
954 }
955
956 kfree(ppace);
957 }
958
959 return;
960 }
961
962
963 static int set_chmod_dacl(struct cifs_acl *pndacl, struct cifs_sid *pownersid,
964 struct cifs_sid *pgrpsid, __u64 nmode)
965 {
966 u16 size = 0;
967 struct cifs_acl *pnndacl;
968
969 pnndacl = (struct cifs_acl *)((char *)pndacl + sizeof(struct cifs_acl));
970
971 size += fill_ace_for_sid((struct cifs_ace *) ((char *)pnndacl + size),
972 pownersid, nmode, S_IRWXU);
973 size += fill_ace_for_sid((struct cifs_ace *)((char *)pnndacl + size),
974 pgrpsid, nmode, S_IRWXG);
975 size += fill_ace_for_sid((struct cifs_ace *)((char *)pnndacl + size),
976 &sid_everyone, nmode, S_IRWXO);
977
978 pndacl->size = cpu_to_le16(size + sizeof(struct cifs_acl));
979 pndacl->num_aces = cpu_to_le32(3);
980
981 return 0;
982 }
983
984
985 static int parse_sid(struct cifs_sid *psid, char *end_of_acl)
986 {
987 /* BB need to add parm so we can store the SID BB */
988
989 /* validate that we do not go past end of ACL - sid must be at least 8
990 bytes long (assuming no sub-auths - e.g. the null SID */
991 if (end_of_acl < (char *)psid + 8) {
992 cERROR(1, "ACL too small to parse SID %p", psid);
993 return -EINVAL;
994 }
995
996 if (psid->num_subauth) {
997 #ifdef CONFIG_CIFS_DEBUG2
998 int i;
999 cFYI(1, "SID revision %d num_auth %d",
1000 psid->revision, psid->num_subauth);
1001
1002 for (i = 0; i < psid->num_subauth; i++) {
1003 cFYI(1, "SID sub_auth[%d]: 0x%x ", i,
1004 le32_to_cpu(psid->sub_auth[i]));
1005 }
1006
1007 /* BB add length check to make sure that we do not have huge
1008 num auths and therefore go off the end */
1009 cFYI(1, "RID 0x%x",
1010 le32_to_cpu(psid->sub_auth[psid->num_subauth-1]));
1011 #endif
1012 }
1013
1014 return 0;
1015 }
1016
1017
1018 /* Convert CIFS ACL to POSIX form */
1019 static int parse_sec_desc(struct cifs_sb_info *cifs_sb,
1020 struct cifs_ntsd *pntsd, int acl_len, struct cifs_fattr *fattr)
1021 {
1022 int rc = 0;
1023 struct cifs_sid *owner_sid_ptr, *group_sid_ptr;
1024 struct cifs_acl *dacl_ptr; /* no need for SACL ptr */
1025 char *end_of_acl = ((char *)pntsd) + acl_len;
1026 __u32 dacloffset;
1027
1028 if (pntsd == NULL)
1029 return -EIO;
1030
1031 owner_sid_ptr = (struct cifs_sid *)((char *)pntsd +
1032 le32_to_cpu(pntsd->osidoffset));
1033 group_sid_ptr = (struct cifs_sid *)((char *)pntsd +
1034 le32_to_cpu(pntsd->gsidoffset));
1035 dacloffset = le32_to_cpu(pntsd->dacloffset);
1036 dacl_ptr = (struct cifs_acl *)((char *)pntsd + dacloffset);
1037 cFYI(DBG2, "revision %d type 0x%x ooffset 0x%x goffset 0x%x "
1038 "sacloffset 0x%x dacloffset 0x%x",
1039 pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
1040 le32_to_cpu(pntsd->gsidoffset),
1041 le32_to_cpu(pntsd->sacloffset), dacloffset);
1042 /* cifs_dump_mem("owner_sid: ", owner_sid_ptr, 64); */
1043 rc = parse_sid(owner_sid_ptr, end_of_acl);
1044 if (rc) {
1045 cFYI(1, "%s: Error %d parsing Owner SID", __func__, rc);
1046 return rc;
1047 }
1048 rc = sid_to_id(cifs_sb, owner_sid_ptr, fattr, SIDOWNER);
1049 if (rc) {
1050 cFYI(1, "%s: Error %d mapping Owner SID to uid", __func__, rc);
1051 return rc;
1052 }
1053
1054 rc = parse_sid(group_sid_ptr, end_of_acl);
1055 if (rc) {
1056 cFYI(1, "%s: Error %d mapping Owner SID to gid", __func__, rc);
1057 return rc;
1058 }
1059 rc = sid_to_id(cifs_sb, group_sid_ptr, fattr, SIDGROUP);
1060 if (rc) {
1061 cFYI(1, "%s: Error %d mapping Group SID to gid", __func__, rc);
1062 return rc;
1063 }
1064
1065 if (dacloffset)
1066 parse_dacl(dacl_ptr, end_of_acl, owner_sid_ptr,
1067 group_sid_ptr, fattr);
1068 else
1069 cFYI(1, "no ACL"); /* BB grant all or default perms? */
1070
1071 return rc;
1072 }
1073
1074 /* Convert permission bits from mode to equivalent CIFS ACL */
1075 static int build_sec_desc(struct cifs_ntsd *pntsd, struct cifs_ntsd *pnntsd,
1076 __u32 secdesclen, __u64 nmode, uid_t uid, gid_t gid, int *aclflag)
1077 {
1078 int rc = 0;
1079 __u32 dacloffset;
1080 __u32 ndacloffset;
1081 __u32 sidsoffset;
1082 struct cifs_sid *owner_sid_ptr, *group_sid_ptr;
1083 struct cifs_sid *nowner_sid_ptr, *ngroup_sid_ptr;
1084 struct cifs_acl *dacl_ptr = NULL; /* no need for SACL ptr */
1085 struct cifs_acl *ndacl_ptr = NULL; /* no need for SACL ptr */
1086
1087 if (nmode != NO_CHANGE_64) { /* chmod */
1088 owner_sid_ptr = (struct cifs_sid *)((char *)pntsd +
1089 le32_to_cpu(pntsd->osidoffset));
1090 group_sid_ptr = (struct cifs_sid *)((char *)pntsd +
1091 le32_to_cpu(pntsd->gsidoffset));
1092 dacloffset = le32_to_cpu(pntsd->dacloffset);
1093 dacl_ptr = (struct cifs_acl *)((char *)pntsd + dacloffset);
1094 ndacloffset = sizeof(struct cifs_ntsd);
1095 ndacl_ptr = (struct cifs_acl *)((char *)pnntsd + ndacloffset);
1096 ndacl_ptr->revision = dacl_ptr->revision;
1097 ndacl_ptr->size = 0;
1098 ndacl_ptr->num_aces = 0;
1099
1100 rc = set_chmod_dacl(ndacl_ptr, owner_sid_ptr, group_sid_ptr,
1101 nmode);
1102 sidsoffset = ndacloffset + le16_to_cpu(ndacl_ptr->size);
1103 /* copy sec desc control portion & owner and group sids */
1104 copy_sec_desc(pntsd, pnntsd, sidsoffset);
1105 *aclflag = CIFS_ACL_DACL;
1106 } else {
1107 memcpy(pnntsd, pntsd, secdesclen);
1108 if (uid != NO_CHANGE_32) { /* chown */
1109 owner_sid_ptr = (struct cifs_sid *)((char *)pnntsd +
1110 le32_to_cpu(pnntsd->osidoffset));
1111 nowner_sid_ptr = kmalloc(sizeof(struct cifs_sid),
1112 GFP_KERNEL);
1113 if (!nowner_sid_ptr)
1114 return -ENOMEM;
1115 rc = id_to_sid(uid, SIDOWNER, nowner_sid_ptr);
1116 if (rc) {
1117 cFYI(1, "%s: Mapping error %d for owner id %d",
1118 __func__, rc, uid);
1119 kfree(nowner_sid_ptr);
1120 return rc;
1121 }
1122 memcpy(owner_sid_ptr, nowner_sid_ptr,
1123 sizeof(struct cifs_sid));
1124 kfree(nowner_sid_ptr);
1125 *aclflag = CIFS_ACL_OWNER;
1126 }
1127 if (gid != NO_CHANGE_32) { /* chgrp */
1128 group_sid_ptr = (struct cifs_sid *)((char *)pnntsd +
1129 le32_to_cpu(pnntsd->gsidoffset));
1130 ngroup_sid_ptr = kmalloc(sizeof(struct cifs_sid),
1131 GFP_KERNEL);
1132 if (!ngroup_sid_ptr)
1133 return -ENOMEM;
1134 rc = id_to_sid(gid, SIDGROUP, ngroup_sid_ptr);
1135 if (rc) {
1136 cFYI(1, "%s: Mapping error %d for group id %d",
1137 __func__, rc, gid);
1138 kfree(ngroup_sid_ptr);
1139 return rc;
1140 }
1141 memcpy(group_sid_ptr, ngroup_sid_ptr,
1142 sizeof(struct cifs_sid));
1143 kfree(ngroup_sid_ptr);
1144 *aclflag = CIFS_ACL_GROUP;
1145 }
1146 }
1147
1148 return rc;
1149 }
1150
1151 static struct cifs_ntsd *get_cifs_acl_by_fid(struct cifs_sb_info *cifs_sb,
1152 __u16 fid, u32 *pacllen)
1153 {
1154 struct cifs_ntsd *pntsd = NULL;
1155 int xid, rc;
1156 struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
1157
1158 if (IS_ERR(tlink))
1159 return ERR_CAST(tlink);
1160
1161 xid = GetXid();
1162 rc = CIFSSMBGetCIFSACL(xid, tlink_tcon(tlink), fid, &pntsd, pacllen);
1163 FreeXid(xid);
1164
1165 cifs_put_tlink(tlink);
1166
1167 cFYI(1, "%s: rc = %d ACL len %d", __func__, rc, *pacllen);
1168 if (rc)
1169 return ERR_PTR(rc);
1170 return pntsd;
1171 }
1172
1173 static struct cifs_ntsd *get_cifs_acl_by_path(struct cifs_sb_info *cifs_sb,
1174 const char *path, u32 *pacllen)
1175 {
1176 struct cifs_ntsd *pntsd = NULL;
1177 int oplock = 0;
1178 int xid, rc, create_options = 0;
1179 __u16 fid;
1180 struct cifs_tcon *tcon;
1181 struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
1182
1183 if (IS_ERR(tlink))
1184 return ERR_CAST(tlink);
1185
1186 tcon = tlink_tcon(tlink);
1187 xid = GetXid();
1188
1189 if (backup_cred(cifs_sb))
1190 create_options |= CREATE_OPEN_BACKUP_INTENT;
1191
1192 rc = CIFSSMBOpen(xid, tcon, path, FILE_OPEN, READ_CONTROL,
1193 create_options, &fid, &oplock, NULL, cifs_sb->local_nls,
1194 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
1195 if (!rc) {
1196 rc = CIFSSMBGetCIFSACL(xid, tcon, fid, &pntsd, pacllen);
1197 CIFSSMBClose(xid, tcon, fid);
1198 }
1199
1200 cifs_put_tlink(tlink);
1201 FreeXid(xid);
1202
1203 cFYI(1, "%s: rc = %d ACL len %d", __func__, rc, *pacllen);
1204 if (rc)
1205 return ERR_PTR(rc);
1206 return pntsd;
1207 }
1208
1209 /* Retrieve an ACL from the server */
1210 struct cifs_ntsd *get_cifs_acl(struct cifs_sb_info *cifs_sb,
1211 struct inode *inode, const char *path,
1212 u32 *pacllen)
1213 {
1214 struct cifs_ntsd *pntsd = NULL;
1215 struct cifsFileInfo *open_file = NULL;
1216
1217 if (inode)
1218 open_file = find_readable_file(CIFS_I(inode), true);
1219 if (!open_file)
1220 return get_cifs_acl_by_path(cifs_sb, path, pacllen);
1221
1222 pntsd = get_cifs_acl_by_fid(cifs_sb, open_file->netfid, pacllen);
1223 cifsFileInfo_put(open_file);
1224 return pntsd;
1225 }
1226
1227 /* Set an ACL on the server */
1228 int set_cifs_acl(struct cifs_ntsd *pnntsd, __u32 acllen,
1229 struct inode *inode, const char *path, int aclflag)
1230 {
1231 int oplock = 0;
1232 int xid, rc, access_flags, create_options = 0;
1233 __u16 fid;
1234 struct cifs_tcon *tcon;
1235 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
1236 struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
1237
1238 if (IS_ERR(tlink))
1239 return PTR_ERR(tlink);
1240
1241 tcon = tlink_tcon(tlink);
1242 xid = GetXid();
1243
1244 if (backup_cred(cifs_sb))
1245 create_options |= CREATE_OPEN_BACKUP_INTENT;
1246
1247 if (aclflag == CIFS_ACL_OWNER || aclflag == CIFS_ACL_GROUP)
1248 access_flags = WRITE_OWNER;
1249 else
1250 access_flags = WRITE_DAC;
1251
1252 rc = CIFSSMBOpen(xid, tcon, path, FILE_OPEN, access_flags,
1253 create_options, &fid, &oplock, NULL, cifs_sb->local_nls,
1254 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
1255 if (rc) {
1256 cERROR(1, "Unable to open file to set ACL");
1257 goto out;
1258 }
1259
1260 rc = CIFSSMBSetCIFSACL(xid, tcon, fid, pnntsd, acllen, aclflag);
1261 cFYI(DBG2, "SetCIFSACL rc = %d", rc);
1262
1263 CIFSSMBClose(xid, tcon, fid);
1264 out:
1265 FreeXid(xid);
1266 cifs_put_tlink(tlink);
1267 return rc;
1268 }
1269
1270 /* Translate the CIFS ACL (simlar to NTFS ACL) for a file into mode bits */
1271 int
1272 cifs_acl_to_fattr(struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr,
1273 struct inode *inode, const char *path, const __u16 *pfid)
1274 {
1275 struct cifs_ntsd *pntsd = NULL;
1276 u32 acllen = 0;
1277 int rc = 0;
1278
1279 cFYI(DBG2, "converting ACL to mode for %s", path);
1280
1281 if (pfid)
1282 pntsd = get_cifs_acl_by_fid(cifs_sb, *pfid, &acllen);
1283 else
1284 pntsd = get_cifs_acl(cifs_sb, inode, path, &acllen);
1285
1286 /* if we can retrieve the ACL, now parse Access Control Entries, ACEs */
1287 if (IS_ERR(pntsd)) {
1288 rc = PTR_ERR(pntsd);
1289 cERROR(1, "%s: error %d getting sec desc", __func__, rc);
1290 } else {
1291 rc = parse_sec_desc(cifs_sb, pntsd, acllen, fattr);
1292 kfree(pntsd);
1293 if (rc)
1294 cERROR(1, "parse sec desc failed rc = %d", rc);
1295 }
1296
1297 return rc;
1298 }
1299
1300 /* Convert mode bits to an ACL so we can update the ACL on the server */
1301 int
1302 id_mode_to_cifs_acl(struct inode *inode, const char *path, __u64 nmode,
1303 uid_t uid, gid_t gid)
1304 {
1305 int rc = 0;
1306 int aclflag = CIFS_ACL_DACL; /* default flag to set */
1307 __u32 secdesclen = 0;
1308 struct cifs_ntsd *pntsd = NULL; /* acl obtained from server */
1309 struct cifs_ntsd *pnntsd = NULL; /* modified acl to be sent to server */
1310
1311 cFYI(DBG2, "set ACL from mode for %s", path);
1312
1313 /* Get the security descriptor */
1314 pntsd = get_cifs_acl(CIFS_SB(inode->i_sb), inode, path, &secdesclen);
1315
1316 /* Add three ACEs for owner, group, everyone getting rid of
1317 other ACEs as chmod disables ACEs and set the security descriptor */
1318
1319 if (IS_ERR(pntsd)) {
1320 rc = PTR_ERR(pntsd);
1321 cERROR(1, "%s: error %d getting sec desc", __func__, rc);
1322 } else {
1323 /* allocate memory for the smb header,
1324 set security descriptor request security descriptor
1325 parameters, and secuirty descriptor itself */
1326
1327 secdesclen = secdesclen < DEFSECDESCLEN ?
1328 DEFSECDESCLEN : secdesclen;
1329 pnntsd = kmalloc(secdesclen, GFP_KERNEL);
1330 if (!pnntsd) {
1331 cERROR(1, "Unable to allocate security descriptor");
1332 kfree(pntsd);
1333 return -ENOMEM;
1334 }
1335
1336 rc = build_sec_desc(pntsd, pnntsd, secdesclen, nmode, uid, gid,
1337 &aclflag);
1338
1339 cFYI(DBG2, "build_sec_desc rc: %d", rc);
1340
1341 if (!rc) {
1342 /* Set the security descriptor */
1343 rc = set_cifs_acl(pnntsd, secdesclen, inode,
1344 path, aclflag);
1345 cFYI(DBG2, "set_cifs_acl rc: %d", rc);
1346 }
1347
1348 kfree(pnntsd);
1349 kfree(pntsd);
1350 }
1351
1352 return rc;
1353 }