1 // SPDX-License-Identifier: LGPL-2.1+
2 /*
3 * Copyright (C) International Business Machines Corp., 2007,2008
4 * Author(s): Steve French (sfrench@us.ibm.com)
5 * Copyright (C) 2020 Samsung Electronics Co., Ltd.
6 * Author(s): Namjae Jeon <linkinjeon@kernel.org>
7 */
8
9 #include <linux/fs.h>
10 #include <linux/slab.h>
11 #include <linux/string.h>
12 #include <linux/mnt_idmapping.h>
13
14 #include "smbacl.h"
15 #include "smb_common.h"
16 #include "server.h"
17 #include "misc.h"
18 #include "mgmt/share_config.h"
19
20 static const struct smb_sid domain = {1, 4, {0, 0, 0, 0, 0, 5},
21 {cpu_to_le32(21), cpu_to_le32(1), cpu_to_le32(2), cpu_to_le32(3),
22 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
23
24 /* security id for everyone/world system group */
25 static const struct smb_sid creator_owner = {
26 1, 1, {0, 0, 0, 0, 0, 3}, {0} };
27 /* security id for everyone/world system group */
28 static const struct smb_sid creator_group = {
29 1, 1, {0, 0, 0, 0, 0, 3}, {cpu_to_le32(1)} };
30
31 /* security id for everyone/world system group */
32 static const struct smb_sid sid_everyone = {
33 1, 1, {0, 0, 0, 0, 0, 1}, {0} };
34 /* security id for Authenticated Users system group */
35 static const struct smb_sid sid_authusers = {
36 1, 1, {0, 0, 0, 0, 0, 5}, {cpu_to_le32(11)} };
37
38 /* S-1-22-1 Unmapped Unix users */
39 static const struct smb_sid sid_unix_users = {1, 1, {0, 0, 0, 0, 0, 22},
40 {cpu_to_le32(1), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
41
42 /* S-1-22-2 Unmapped Unix groups */
43 static const struct smb_sid sid_unix_groups = { 1, 1, {0, 0, 0, 0, 0, 22},
44 {cpu_to_le32(2), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
45
46 /*
47 * See http://technet.microsoft.com/en-us/library/hh509017(v=ws.10).aspx
48 */
49
50 /* S-1-5-88 MS NFS and Apple style UID/GID/mode */
51
52 /* S-1-5-88-1 Unix uid */
53 static const struct smb_sid sid_unix_NFS_users = { 1, 2, {0, 0, 0, 0, 0, 5},
54 {cpu_to_le32(88),
55 cpu_to_le32(1), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
56
57 /* S-1-5-88-2 Unix gid */
58 static const struct smb_sid sid_unix_NFS_groups = { 1, 2, {0, 0, 0, 0, 0, 5},
59 {cpu_to_le32(88),
60 cpu_to_le32(2), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
61
62 /* S-1-5-88-3 Unix mode */
63 static const struct smb_sid sid_unix_NFS_mode = { 1, 2, {0, 0, 0, 0, 0, 5},
64 {cpu_to_le32(88),
65 cpu_to_le32(3), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
66
67 /*
68 * if the two SIDs (roughly equivalent to a UUID for a user or group) are
69 * the same returns zero, if they do not match returns non-zero.
70 */
compare_sids(const struct smb_sid * ctsid,const struct smb_sid * cwsid)71 int compare_sids(const struct smb_sid *ctsid, const struct smb_sid *cwsid)
72 {
73 int i;
74 int num_subauth, num_sat, num_saw;
75
76 if (!ctsid || !cwsid)
77 return 1;
78
79 /* compare the revision */
80 if (ctsid->revision != cwsid->revision) {
81 if (ctsid->revision > cwsid->revision)
82 return 1;
83 else
84 return -1;
85 }
86
87 /* compare all of the six auth values */
88 for (i = 0; i < NUM_AUTHS; ++i) {
89 if (ctsid->authority[i] != cwsid->authority[i]) {
90 if (ctsid->authority[i] > cwsid->authority[i])
91 return 1;
92 else
93 return -1;
94 }
95 }
96
97 /* compare all of the subauth values if any */
98 num_sat = ctsid->num_subauth;
99 num_saw = cwsid->num_subauth;
100 num_subauth = min(num_sat, num_saw);
101 if (num_subauth) {
102 for (i = 0; i < num_subauth; ++i) {
103 if (ctsid->sub_auth[i] != cwsid->sub_auth[i]) {
104 if (le32_to_cpu(ctsid->sub_auth[i]) >
105 le32_to_cpu(cwsid->sub_auth[i]))
106 return 1;
107 else
108 return -1;
109 }
110 }
111 }
112
113 return 0; /* sids compare/match */
114 }
115
smb_copy_sid(struct smb_sid * dst,const struct smb_sid * src)116 static void smb_copy_sid(struct smb_sid *dst, const struct smb_sid *src)
117 {
118 int i;
119
120 dst->revision = src->revision;
121 dst->num_subauth = min_t(u8, src->num_subauth, SID_MAX_SUB_AUTHORITIES);
122 for (i = 0; i < NUM_AUTHS; ++i)
123 dst->authority[i] = src->authority[i];
124 for (i = 0; i < dst->num_subauth; ++i)
125 dst->sub_auth[i] = src->sub_auth[i];
126 }
127
128 /*
129 * change posix mode to reflect permissions
130 * pmode is the existing mode (we only want to overwrite part of this
131 * bits to set can be: S_IRWXU, S_IRWXG or S_IRWXO ie 00700 or 00070 or 00007
132 */
access_flags_to_mode(struct smb_fattr * fattr,__le32 ace_flags,int type)133 static umode_t access_flags_to_mode(struct smb_fattr *fattr, __le32 ace_flags,
134 int type)
135 {
136 __u32 flags = le32_to_cpu(ace_flags);
137 umode_t mode = 0;
138
139 if (flags & GENERIC_ALL) {
140 mode = 0777;
141 ksmbd_debug(SMB, "all perms\n");
142 return mode;
143 }
144
145 if ((flags & GENERIC_READ) || (flags & FILE_READ_RIGHTS))
146 mode = 0444;
147 if ((flags & GENERIC_WRITE) || (flags & FILE_WRITE_RIGHTS)) {
148 mode |= 0222;
149 if (S_ISDIR(fattr->cf_mode))
150 mode |= 0111;
151 }
152 if ((flags & GENERIC_EXECUTE) || (flags & FILE_EXEC_RIGHTS))
153 mode |= 0111;
154
155 if (type == ACCESS_DENIED_ACE_TYPE || type == ACCESS_DENIED_OBJECT_ACE_TYPE)
156 mode = ~mode;
157
158 ksmbd_debug(SMB, "access flags 0x%x mode now %04o\n", flags, mode);
159
160 return mode;
161 }
162
163 /*
164 * Generate access flags to reflect permissions mode is the existing mode.
165 * This function is called for every ACE in the DACL whose SID matches
166 * with either owner or group or everyone.
167 */
mode_to_access_flags(umode_t mode,umode_t bits_to_use,__u32 * pace_flags)168 static void mode_to_access_flags(umode_t mode, umode_t bits_to_use,
169 __u32 *pace_flags)
170 {
171 /* reset access mask */
172 *pace_flags = 0x0;
173
174 /* bits to use are either S_IRWXU or S_IRWXG or S_IRWXO */
175 mode &= bits_to_use;
176
177 /*
178 * check for R/W/X UGO since we do not know whose flags
179 * is this but we have cleared all the bits sans RWX for
180 * either user or group or other as per bits_to_use
181 */
182 if (mode & 0444)
183 *pace_flags |= SET_FILE_READ_RIGHTS;
184 if (mode & 0222)
185 *pace_flags |= FILE_WRITE_RIGHTS;
186 if (mode & 0111)
187 *pace_flags |= SET_FILE_EXEC_RIGHTS;
188
189 ksmbd_debug(SMB, "mode: %o, access flags now 0x%x\n",
190 mode, *pace_flags);
191 }
192
fill_ace_for_sid(struct smb_ace * pntace,const struct smb_sid * psid,int type,int flags,umode_t mode,umode_t bits)193 static __u16 fill_ace_for_sid(struct smb_ace *pntace,
194 const struct smb_sid *psid, int type, int flags,
195 umode_t mode, umode_t bits)
196 {
197 int i;
198 __u16 size = 0;
199 __u32 access_req = 0;
200
201 pntace->type = type;
202 pntace->flags = flags;
203 mode_to_access_flags(mode, bits, &access_req);
204 if (!access_req)
205 access_req = SET_MINIMUM_RIGHTS;
206 pntace->access_req = cpu_to_le32(access_req);
207
208 pntace->sid.revision = psid->revision;
209 pntace->sid.num_subauth = psid->num_subauth;
210 for (i = 0; i < NUM_AUTHS; i++)
211 pntace->sid.authority[i] = psid->authority[i];
212 for (i = 0; i < psid->num_subauth; i++)
213 pntace->sid.sub_auth[i] = psid->sub_auth[i];
214
215 size = 1 + 1 + 2 + 4 + 1 + 1 + 6 + (psid->num_subauth * 4);
216 pntace->size = cpu_to_le16(size);
217
218 return size;
219 }
220
id_to_sid(unsigned int cid,uint sidtype,struct smb_sid * ssid)221 void id_to_sid(unsigned int cid, uint sidtype, struct smb_sid *ssid)
222 {
223 switch (sidtype) {
224 case SIDOWNER:
225 smb_copy_sid(ssid, &server_conf.domain_sid);
226 break;
227 case SIDUNIX_USER:
228 smb_copy_sid(ssid, &sid_unix_users);
229 break;
230 case SIDUNIX_GROUP:
231 smb_copy_sid(ssid, &sid_unix_groups);
232 break;
233 case SIDCREATOR_OWNER:
234 smb_copy_sid(ssid, &creator_owner);
235 return;
236 case SIDCREATOR_GROUP:
237 smb_copy_sid(ssid, &creator_group);
238 return;
239 case SIDNFS_USER:
240 smb_copy_sid(ssid, &sid_unix_NFS_users);
241 break;
242 case SIDNFS_GROUP:
243 smb_copy_sid(ssid, &sid_unix_NFS_groups);
244 break;
245 case SIDNFS_MODE:
246 smb_copy_sid(ssid, &sid_unix_NFS_mode);
247 break;
248 default:
249 return;
250 }
251
252 /* RID */
253 ssid->sub_auth[ssid->num_subauth] = cpu_to_le32(cid);
254 ssid->num_subauth++;
255 }
256
sid_to_id(struct mnt_idmap * idmap,struct smb_sid * psid,uint sidtype,struct smb_fattr * fattr)257 static int sid_to_id(struct mnt_idmap *idmap,
258 struct smb_sid *psid, uint sidtype,
259 struct smb_fattr *fattr)
260 {
261 int rc = -EINVAL;
262
263 /*
264 * If we have too many subauthorities, then something is really wrong.
265 * Just return an error.
266 */
267 if (unlikely(psid->num_subauth > SID_MAX_SUB_AUTHORITIES)) {
268 pr_err("%s: %u subauthorities is too many!\n",
269 __func__, psid->num_subauth);
270 return -EIO;
271 }
272
273 if (sidtype == SIDOWNER) {
274 kuid_t uid;
275 uid_t id;
276
277 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
278 uid = KUIDT_INIT(id);
279 uid = from_vfsuid(idmap, &init_user_ns, VFSUIDT_INIT(uid));
280 if (uid_valid(uid)) {
281 fattr->cf_uid = uid;
282 rc = 0;
283 }
284 } else {
285 kgid_t gid;
286 gid_t id;
287
288 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
289 gid = KGIDT_INIT(id);
290 gid = from_vfsgid(idmap, &init_user_ns, VFSGIDT_INIT(gid));
291 if (gid_valid(gid)) {
292 fattr->cf_gid = gid;
293 rc = 0;
294 }
295 }
296
297 return rc;
298 }
299
posix_state_to_acl(struct posix_acl_state * state,struct posix_acl_entry * pace)300 void posix_state_to_acl(struct posix_acl_state *state,
301 struct posix_acl_entry *pace)
302 {
303 int i;
304
305 pace->e_tag = ACL_USER_OBJ;
306 pace->e_perm = state->owner.allow;
307 for (i = 0; i < state->users->n; i++) {
308 pace++;
309 pace->e_tag = ACL_USER;
310 pace->e_uid = state->users->aces[i].uid;
311 pace->e_perm = state->users->aces[i].perms.allow;
312 }
313
314 pace++;
315 pace->e_tag = ACL_GROUP_OBJ;
316 pace->e_perm = state->group.allow;
317
318 for (i = 0; i < state->groups->n; i++) {
319 pace++;
320 pace->e_tag = ACL_GROUP;
321 pace->e_gid = state->groups->aces[i].gid;
322 pace->e_perm = state->groups->aces[i].perms.allow;
323 }
324
325 if (state->users->n || state->groups->n) {
326 pace++;
327 pace->e_tag = ACL_MASK;
328 pace->e_perm = state->mask.allow;
329 }
330
331 pace++;
332 pace->e_tag = ACL_OTHER;
333 pace->e_perm = state->other.allow;
334 }
335
init_acl_state(struct posix_acl_state * state,int cnt)336 int init_acl_state(struct posix_acl_state *state, int cnt)
337 {
338 int alloc;
339
340 memset(state, 0, sizeof(struct posix_acl_state));
341 /*
342 * In the worst case, each individual acl could be for a distinct
343 * named user or group, but we don't know which, so we allocate
344 * enough space for either:
345 */
346 alloc = sizeof(struct posix_ace_state_array)
347 + cnt * sizeof(struct posix_user_ace_state);
348 state->users = kzalloc(alloc, GFP_KERNEL);
349 if (!state->users)
350 return -ENOMEM;
351 state->groups = kzalloc(alloc, GFP_KERNEL);
352 if (!state->groups) {
353 kfree(state->users);
354 return -ENOMEM;
355 }
356 return 0;
357 }
358
free_acl_state(struct posix_acl_state * state)359 void free_acl_state(struct posix_acl_state *state)
360 {
361 kfree(state->users);
362 kfree(state->groups);
363 }
364
parse_dacl(struct mnt_idmap * idmap,struct smb_acl * pdacl,char * end_of_acl,struct smb_sid * pownersid,struct smb_sid * pgrpsid,struct smb_fattr * fattr)365 static void parse_dacl(struct mnt_idmap *idmap,
366 struct smb_acl *pdacl, char *end_of_acl,
367 struct smb_sid *pownersid, struct smb_sid *pgrpsid,
368 struct smb_fattr *fattr)
369 {
370 int i, ret;
371 int num_aces = 0;
372 unsigned int acl_size;
373 char *acl_base;
374 struct smb_ace **ppace;
375 struct posix_acl_entry *cf_pace, *cf_pdace;
376 struct posix_acl_state acl_state, default_acl_state;
377 umode_t mode = 0, acl_mode;
378 bool owner_found = false, group_found = false, others_found = false;
379
380 if (!pdacl)
381 return;
382
383 /* validate that we do not go past end of acl */
384 if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) ||
385 end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) {
386 pr_err("ACL too small to parse DACL\n");
387 return;
388 }
389
390 ksmbd_debug(SMB, "DACL revision %d size %d num aces %d\n",
391 le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size),
392 le32_to_cpu(pdacl->num_aces));
393
394 acl_base = (char *)pdacl;
395 acl_size = sizeof(struct smb_acl);
396
397 num_aces = le32_to_cpu(pdacl->num_aces);
398 if (num_aces <= 0)
399 return;
400
401 if (num_aces > (le16_to_cpu(pdacl->size) - sizeof(struct smb_acl)) /
402 (offsetof(struct smb_ace, sid) +
403 offsetof(struct smb_sid, sub_auth) + sizeof(__le16)))
404 return;
405
406 ret = init_acl_state(&acl_state, num_aces);
407 if (ret)
408 return;
409 ret = init_acl_state(&default_acl_state, num_aces);
410 if (ret) {
411 free_acl_state(&acl_state);
412 return;
413 }
414
415 ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL);
416 if (!ppace) {
417 free_acl_state(&default_acl_state);
418 free_acl_state(&acl_state);
419 return;
420 }
421
422 /*
423 * reset rwx permissions for user/group/other.
424 * Also, if num_aces is 0 i.e. DACL has no ACEs,
425 * user/group/other have no permissions
426 */
427 for (i = 0; i < num_aces; ++i) {
428 if (end_of_acl - acl_base < acl_size)
429 break;
430
431 ppace[i] = (struct smb_ace *)(acl_base + acl_size);
432 acl_base = (char *)ppace[i];
433 acl_size = offsetof(struct smb_ace, sid) +
434 offsetof(struct smb_sid, sub_auth);
435
436 if (end_of_acl - acl_base < acl_size ||
437 ppace[i]->sid.num_subauth == 0 ||
438 ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES ||
439 (end_of_acl - acl_base <
440 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) ||
441 (le16_to_cpu(ppace[i]->size) <
442 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth))
443 break;
444
445 acl_size = le16_to_cpu(ppace[i]->size);
446 ppace[i]->access_req =
447 smb_map_generic_desired_access(ppace[i]->access_req);
448
449 if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) {
450 fattr->cf_mode =
451 le32_to_cpu(ppace[i]->sid.sub_auth[2]);
452 break;
453 } else if (!compare_sids(&ppace[i]->sid, pownersid)) {
454 acl_mode = access_flags_to_mode(fattr,
455 ppace[i]->access_req,
456 ppace[i]->type);
457 acl_mode &= 0700;
458
459 if (!owner_found) {
460 mode &= ~(0700);
461 mode |= acl_mode;
462 }
463 owner_found = true;
464 } else if (!compare_sids(&ppace[i]->sid, pgrpsid) ||
465 ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] ==
466 DOMAIN_USER_RID_LE) {
467 acl_mode = access_flags_to_mode(fattr,
468 ppace[i]->access_req,
469 ppace[i]->type);
470 acl_mode &= 0070;
471 if (!group_found) {
472 mode &= ~(0070);
473 mode |= acl_mode;
474 }
475 group_found = true;
476 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) {
477 acl_mode = access_flags_to_mode(fattr,
478 ppace[i]->access_req,
479 ppace[i]->type);
480 acl_mode &= 0007;
481 if (!others_found) {
482 mode &= ~(0007);
483 mode |= acl_mode;
484 }
485 others_found = true;
486 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) {
487 continue;
488 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) {
489 continue;
490 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) {
491 continue;
492 } else {
493 struct smb_fattr temp_fattr;
494
495 acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
496 ppace[i]->type);
497 temp_fattr.cf_uid = INVALID_UID;
498 ret = sid_to_id(idmap, &ppace[i]->sid, SIDOWNER, &temp_fattr);
499 if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) {
500 pr_err("%s: Error %d mapping Owner SID to uid\n",
501 __func__, ret);
502 continue;
503 }
504
505 acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
506 acl_state.users->aces[acl_state.users->n].uid =
507 temp_fattr.cf_uid;
508 acl_state.users->aces[acl_state.users->n++].perms.allow =
509 ((acl_mode & 0700) >> 6) | 0004;
510 default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
511 default_acl_state.users->aces[default_acl_state.users->n].uid =
512 temp_fattr.cf_uid;
513 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
514 ((acl_mode & 0700) >> 6) | 0004;
515 }
516 }
517 kfree(ppace);
518
519 if (owner_found) {
520 /* The owner must be set to at least read-only. */
521 acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
522 acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid;
523 acl_state.users->aces[acl_state.users->n++].perms.allow =
524 ((mode & 0700) >> 6) | 0004;
525 default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
526 default_acl_state.users->aces[default_acl_state.users->n].uid =
527 fattr->cf_uid;
528 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
529 ((mode & 0700) >> 6) | 0004;
530 }
531
532 if (group_found) {
533 acl_state.group.allow = (mode & 0070) >> 3;
534 acl_state.groups->aces[acl_state.groups->n].gid =
535 fattr->cf_gid;
536 acl_state.groups->aces[acl_state.groups->n++].perms.allow =
537 (mode & 0070) >> 3;
538 default_acl_state.group.allow = (mode & 0070) >> 3;
539 default_acl_state.groups->aces[default_acl_state.groups->n].gid =
540 fattr->cf_gid;
541 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow =
542 (mode & 0070) >> 3;
543 }
544
545 if (others_found) {
546 fattr->cf_mode &= ~(0007);
547 fattr->cf_mode |= mode & 0007;
548
549 acl_state.other.allow = mode & 0007;
550 default_acl_state.other.allow = mode & 0007;
551 }
552
553 if (acl_state.users->n || acl_state.groups->n) {
554 acl_state.mask.allow = 0x07;
555
556 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
557 fattr->cf_acls =
558 posix_acl_alloc(acl_state.users->n +
559 acl_state.groups->n + 4, GFP_KERNEL);
560 if (fattr->cf_acls) {
561 cf_pace = fattr->cf_acls->a_entries;
562 posix_state_to_acl(&acl_state, cf_pace);
563 }
564 }
565 }
566
567 if (default_acl_state.users->n || default_acl_state.groups->n) {
568 default_acl_state.mask.allow = 0x07;
569
570 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
571 fattr->cf_dacls =
572 posix_acl_alloc(default_acl_state.users->n +
573 default_acl_state.groups->n + 4, GFP_KERNEL);
574 if (fattr->cf_dacls) {
575 cf_pdace = fattr->cf_dacls->a_entries;
576 posix_state_to_acl(&default_acl_state, cf_pdace);
577 }
578 }
579 }
580 free_acl_state(&acl_state);
581 free_acl_state(&default_acl_state);
582 }
583
set_posix_acl_entries_dacl(struct mnt_idmap * idmap,struct smb_ace * pndace,struct smb_fattr * fattr,u32 * num_aces,u16 * size,u32 nt_aces_num)584 static void set_posix_acl_entries_dacl(struct mnt_idmap *idmap,
585 struct smb_ace *pndace,
586 struct smb_fattr *fattr, u32 *num_aces,
587 u16 *size, u32 nt_aces_num)
588 {
589 struct posix_acl_entry *pace;
590 struct smb_sid *sid;
591 struct smb_ace *ntace;
592 int i, j;
593
594 if (!fattr->cf_acls)
595 goto posix_default_acl;
596
597 pace = fattr->cf_acls->a_entries;
598 for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) {
599 int flags = 0;
600
601 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
602 if (!sid)
603 break;
604
605 if (pace->e_tag == ACL_USER) {
606 uid_t uid;
607 unsigned int sid_type = SIDOWNER;
608
609 uid = posix_acl_uid_translate(idmap, pace);
610 if (!uid)
611 sid_type = SIDUNIX_USER;
612 id_to_sid(uid, sid_type, sid);
613 } else if (pace->e_tag == ACL_GROUP) {
614 gid_t gid;
615
616 gid = posix_acl_gid_translate(idmap, pace);
617 id_to_sid(gid, SIDUNIX_GROUP, sid);
618 } else if (pace->e_tag == ACL_OTHER && !nt_aces_num) {
619 smb_copy_sid(sid, &sid_everyone);
620 } else {
621 kfree(sid);
622 continue;
623 }
624 ntace = pndace;
625 for (j = 0; j < nt_aces_num; j++) {
626 if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] ==
627 sid->sub_auth[sid->num_subauth - 1])
628 goto pass_same_sid;
629 ntace = (struct smb_ace *)((char *)ntace +
630 le16_to_cpu(ntace->size));
631 }
632
633 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER)
634 flags = 0x03;
635
636 ntace = (struct smb_ace *)((char *)pndace + *size);
637 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags,
638 pace->e_perm, 0777);
639 (*num_aces)++;
640 if (pace->e_tag == ACL_USER)
641 ntace->access_req |=
642 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
643
644 if (S_ISDIR(fattr->cf_mode) &&
645 (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) {
646 ntace = (struct smb_ace *)((char *)pndace + *size);
647 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED,
648 0x03, pace->e_perm, 0777);
649 (*num_aces)++;
650 if (pace->e_tag == ACL_USER)
651 ntace->access_req |=
652 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
653 }
654
655 pass_same_sid:
656 kfree(sid);
657 }
658
659 if (nt_aces_num)
660 return;
661
662 posix_default_acl:
663 if (!fattr->cf_dacls)
664 return;
665
666 pace = fattr->cf_dacls->a_entries;
667 for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) {
668 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
669 if (!sid)
670 break;
671
672 if (pace->e_tag == ACL_USER) {
673 uid_t uid;
674
675 uid = posix_acl_uid_translate(idmap, pace);
676 id_to_sid(uid, SIDCREATOR_OWNER, sid);
677 } else if (pace->e_tag == ACL_GROUP) {
678 gid_t gid;
679
680 gid = posix_acl_gid_translate(idmap, pace);
681 id_to_sid(gid, SIDCREATOR_GROUP, sid);
682 } else {
683 kfree(sid);
684 continue;
685 }
686
687 ntace = (struct smb_ace *)((char *)pndace + *size);
688 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b,
689 pace->e_perm, 0777);
690 (*num_aces)++;
691 if (pace->e_tag == ACL_USER)
692 ntace->access_req |=
693 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
694 kfree(sid);
695 }
696 }
697
set_ntacl_dacl(struct mnt_idmap * idmap,struct smb_acl * pndacl,struct smb_acl * nt_dacl,unsigned int aces_size,const struct smb_sid * pownersid,const struct smb_sid * pgrpsid,struct smb_fattr * fattr)698 static void set_ntacl_dacl(struct mnt_idmap *idmap,
699 struct smb_acl *pndacl,
700 struct smb_acl *nt_dacl,
701 unsigned int aces_size,
702 const struct smb_sid *pownersid,
703 const struct smb_sid *pgrpsid,
704 struct smb_fattr *fattr)
705 {
706 struct smb_ace *ntace, *pndace;
707 int nt_num_aces = le32_to_cpu(nt_dacl->num_aces), num_aces = 0;
708 unsigned short size = 0;
709 int i;
710
711 pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
712 if (nt_num_aces) {
713 ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl));
714 for (i = 0; i < nt_num_aces; i++) {
715 unsigned short nt_ace_size;
716
717 if (offsetof(struct smb_ace, access_req) > aces_size)
718 break;
719
720 nt_ace_size = le16_to_cpu(ntace->size);
721 if (nt_ace_size > aces_size)
722 break;
723
724 memcpy((char *)pndace + size, ntace, nt_ace_size);
725 size += nt_ace_size;
726 aces_size -= nt_ace_size;
727 ntace = (struct smb_ace *)((char *)ntace + nt_ace_size);
728 num_aces++;
729 }
730 }
731
732 set_posix_acl_entries_dacl(idmap, pndace, fattr,
733 &num_aces, &size, nt_num_aces);
734 pndacl->num_aces = cpu_to_le32(num_aces);
735 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
736 }
737
set_mode_dacl(struct mnt_idmap * idmap,struct smb_acl * pndacl,struct smb_fattr * fattr)738 static void set_mode_dacl(struct mnt_idmap *idmap,
739 struct smb_acl *pndacl, struct smb_fattr *fattr)
740 {
741 struct smb_ace *pace, *pndace;
742 u32 num_aces = 0;
743 u16 size = 0, ace_size = 0;
744 uid_t uid;
745 const struct smb_sid *sid;
746
747 pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
748
749 if (fattr->cf_acls) {
750 set_posix_acl_entries_dacl(idmap, pndace, fattr,
751 &num_aces, &size, num_aces);
752 goto out;
753 }
754
755 /* owner RID */
756 uid = from_kuid(&init_user_ns, fattr->cf_uid);
757 if (uid)
758 sid = &server_conf.domain_sid;
759 else
760 sid = &sid_unix_users;
761 ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0,
762 fattr->cf_mode, 0700);
763 pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid);
764 pace->size = cpu_to_le16(ace_size + 4);
765 size += le16_to_cpu(pace->size);
766 pace = (struct smb_ace *)((char *)pndace + size);
767
768 /* Group RID */
769 ace_size = fill_ace_for_sid(pace, &sid_unix_groups,
770 ACCESS_ALLOWED, 0, fattr->cf_mode, 0070);
771 pace->sid.sub_auth[pace->sid.num_subauth++] =
772 cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid));
773 pace->size = cpu_to_le16(ace_size + 4);
774 size += le16_to_cpu(pace->size);
775 pace = (struct smb_ace *)((char *)pndace + size);
776 num_aces = 3;
777
778 if (S_ISDIR(fattr->cf_mode)) {
779 pace = (struct smb_ace *)((char *)pndace + size);
780
781 /* creator owner */
782 size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED,
783 0x0b, fattr->cf_mode, 0700);
784 pace = (struct smb_ace *)((char *)pndace + size);
785
786 /* creator group */
787 size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED,
788 0x0b, fattr->cf_mode, 0070);
789 pace = (struct smb_ace *)((char *)pndace + size);
790 num_aces = 5;
791 }
792
793 /* other */
794 size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0,
795 fattr->cf_mode, 0007);
796
797 out:
798 pndacl->num_aces = cpu_to_le32(num_aces);
799 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
800 }
801
parse_sid(struct smb_sid * psid,char * end_of_acl)802 static int parse_sid(struct smb_sid *psid, char *end_of_acl)
803 {
804 /*
805 * validate that we do not go past end of ACL - sid must be at least 8
806 * bytes long (assuming no sub-auths - e.g. the null SID
807 */
808 if (end_of_acl < (char *)psid + 8) {
809 pr_err("ACL too small to parse SID %p\n", psid);
810 return -EINVAL;
811 }
812
813 if (!psid->num_subauth)
814 return 0;
815
816 if (psid->num_subauth > SID_MAX_SUB_AUTHORITIES ||
817 end_of_acl < (char *)psid + 8 + sizeof(__le32) * psid->num_subauth)
818 return -EINVAL;
819
820 return 0;
821 }
822
823 /* Convert CIFS ACL to POSIX form */
parse_sec_desc(struct mnt_idmap * idmap,struct smb_ntsd * pntsd,int acl_len,struct smb_fattr * fattr)824 int parse_sec_desc(struct mnt_idmap *idmap, struct smb_ntsd *pntsd,
825 int acl_len, struct smb_fattr *fattr)
826 {
827 int rc = 0;
828 struct smb_sid *owner_sid_ptr, *group_sid_ptr;
829 struct smb_acl *dacl_ptr; /* no need for SACL ptr */
830 char *end_of_acl = ((char *)pntsd) + acl_len;
831 __u32 dacloffset;
832 int pntsd_type;
833
834 if (!pntsd)
835 return -EIO;
836
837 if (acl_len < sizeof(struct smb_ntsd))
838 return -EINVAL;
839
840 owner_sid_ptr = (struct smb_sid *)((char *)pntsd +
841 le32_to_cpu(pntsd->osidoffset));
842 group_sid_ptr = (struct smb_sid *)((char *)pntsd +
843 le32_to_cpu(pntsd->gsidoffset));
844 dacloffset = le32_to_cpu(pntsd->dacloffset);
845 dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset);
846 ksmbd_debug(SMB,
847 "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n",
848 pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
849 le32_to_cpu(pntsd->gsidoffset),
850 le32_to_cpu(pntsd->sacloffset), dacloffset);
851
852 pntsd_type = le16_to_cpu(pntsd->type);
853 if (!(pntsd_type & DACL_PRESENT)) {
854 ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n");
855 return rc;
856 }
857
858 pntsd->type = cpu_to_le16(DACL_PRESENT);
859
860 if (pntsd->osidoffset) {
861 if (le32_to_cpu(pntsd->osidoffset) < sizeof(struct smb_ntsd))
862 return -EINVAL;
863
864 rc = parse_sid(owner_sid_ptr, end_of_acl);
865 if (rc) {
866 pr_err("%s: Error %d parsing Owner SID\n", __func__, rc);
867 return rc;
868 }
869
870 rc = sid_to_id(idmap, owner_sid_ptr, SIDOWNER, fattr);
871 if (rc) {
872 pr_err("%s: Error %d mapping Owner SID to uid\n",
873 __func__, rc);
874 owner_sid_ptr = NULL;
875 }
876 }
877
878 if (pntsd->gsidoffset) {
879 if (le32_to_cpu(pntsd->gsidoffset) < sizeof(struct smb_ntsd))
880 return -EINVAL;
881
882 rc = parse_sid(group_sid_ptr, end_of_acl);
883 if (rc) {
884 pr_err("%s: Error %d mapping Owner SID to gid\n",
885 __func__, rc);
886 return rc;
887 }
888 rc = sid_to_id(idmap, group_sid_ptr, SIDUNIX_GROUP, fattr);
889 if (rc) {
890 pr_err("%s: Error %d mapping Group SID to gid\n",
891 __func__, rc);
892 group_sid_ptr = NULL;
893 }
894 }
895
896 if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) ==
897 (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ))
898 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
899 if (pntsd_type & DACL_PROTECTED)
900 pntsd->type |= cpu_to_le16(DACL_PROTECTED);
901
902 if (dacloffset) {
903 if (dacloffset < sizeof(struct smb_ntsd))
904 return -EINVAL;
905
906 parse_dacl(idmap, dacl_ptr, end_of_acl,
907 owner_sid_ptr, group_sid_ptr, fattr);
908 }
909
910 return 0;
911 }
912
913 /* Convert permission bits from mode to equivalent CIFS ACL */
build_sec_desc(struct mnt_idmap * idmap,struct smb_ntsd * pntsd,struct smb_ntsd * ppntsd,int ppntsd_size,int addition_info,__u32 * secdesclen,struct smb_fattr * fattr)914 int build_sec_desc(struct mnt_idmap *idmap,
915 struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
916 int ppntsd_size, int addition_info, __u32 *secdesclen,
917 struct smb_fattr *fattr)
918 {
919 int rc = 0;
920 __u32 offset;
921 struct smb_sid *owner_sid_ptr, *group_sid_ptr;
922 struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr;
923 struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */
924 uid_t uid;
925 gid_t gid;
926 unsigned int sid_type = SIDOWNER;
927
928 nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
929 if (!nowner_sid_ptr)
930 return -ENOMEM;
931
932 uid = from_kuid(&init_user_ns, fattr->cf_uid);
933 if (!uid)
934 sid_type = SIDUNIX_USER;
935 id_to_sid(uid, sid_type, nowner_sid_ptr);
936
937 ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
938 if (!ngroup_sid_ptr) {
939 kfree(nowner_sid_ptr);
940 return -ENOMEM;
941 }
942
943 gid = from_kgid(&init_user_ns, fattr->cf_gid);
944 id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr);
945
946 offset = sizeof(struct smb_ntsd);
947 pntsd->sacloffset = 0;
948 pntsd->revision = cpu_to_le16(1);
949 pntsd->type = cpu_to_le16(SELF_RELATIVE);
950 if (ppntsd)
951 pntsd->type |= ppntsd->type;
952
953 if (addition_info & OWNER_SECINFO) {
954 pntsd->osidoffset = cpu_to_le32(offset);
955 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
956 smb_copy_sid(owner_sid_ptr, nowner_sid_ptr);
957 offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4);
958 }
959
960 if (addition_info & GROUP_SECINFO) {
961 pntsd->gsidoffset = cpu_to_le32(offset);
962 group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
963 smb_copy_sid(group_sid_ptr, ngroup_sid_ptr);
964 offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4);
965 }
966
967 if (addition_info & DACL_SECINFO) {
968 pntsd->type |= cpu_to_le16(DACL_PRESENT);
969 dacl_ptr = (struct smb_acl *)((char *)pntsd + offset);
970 dacl_ptr->revision = cpu_to_le16(2);
971 dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl));
972 dacl_ptr->num_aces = 0;
973
974 if (!ppntsd) {
975 set_mode_dacl(idmap, dacl_ptr, fattr);
976 } else {
977 struct smb_acl *ppdacl_ptr;
978 unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset);
979 int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset;
980
981 if (!dacl_offset ||
982 (dacl_offset + sizeof(struct smb_acl) > ppntsd_size))
983 goto out;
984
985 ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset);
986 ppdacl_size = le16_to_cpu(ppdacl_ptr->size);
987 if (ppdacl_size > ntacl_size ||
988 ppdacl_size < sizeof(struct smb_acl))
989 goto out;
990
991 set_ntacl_dacl(idmap, dacl_ptr, ppdacl_ptr,
992 ntacl_size - sizeof(struct smb_acl),
993 nowner_sid_ptr, ngroup_sid_ptr,
994 fattr);
995 }
996 pntsd->dacloffset = cpu_to_le32(offset);
997 offset += le16_to_cpu(dacl_ptr->size);
998 }
999
1000 out:
1001 kfree(nowner_sid_ptr);
1002 kfree(ngroup_sid_ptr);
1003 *secdesclen = offset;
1004 return rc;
1005 }
1006
smb_set_ace(struct smb_ace * ace,const struct smb_sid * sid,u8 type,u8 flags,__le32 access_req)1007 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type,
1008 u8 flags, __le32 access_req)
1009 {
1010 ace->type = type;
1011 ace->flags = flags;
1012 ace->access_req = access_req;
1013 smb_copy_sid(&ace->sid, sid);
1014 ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + (sid->num_subauth * 4));
1015 }
1016
smb_inherit_dacl(struct ksmbd_conn * conn,const struct path * path,unsigned int uid,unsigned int gid)1017 int smb_inherit_dacl(struct ksmbd_conn *conn,
1018 const struct path *path,
1019 unsigned int uid, unsigned int gid)
1020 {
1021 const struct smb_sid *psid, *creator = NULL;
1022 struct smb_ace *parent_aces, *aces;
1023 struct smb_acl *parent_pdacl;
1024 struct smb_ntsd *parent_pntsd = NULL;
1025 struct smb_sid owner_sid, group_sid;
1026 struct dentry *parent = path->dentry->d_parent;
1027 struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1028 int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size;
1029 int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size;
1030 char *aces_base;
1031 bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
1032
1033 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1034 parent, &parent_pntsd);
1035 if (pntsd_size <= 0)
1036 return -ENOENT;
1037 dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
1038 if (!dacloffset || (dacloffset + sizeof(struct smb_acl) > pntsd_size)) {
1039 rc = -EINVAL;
1040 goto free_parent_pntsd;
1041 }
1042
1043 parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset);
1044 acl_len = pntsd_size - dacloffset;
1045 num_aces = le32_to_cpu(parent_pdacl->num_aces);
1046 pntsd_type = le16_to_cpu(parent_pntsd->type);
1047 pdacl_size = le16_to_cpu(parent_pdacl->size);
1048
1049 if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) {
1050 rc = -EINVAL;
1051 goto free_parent_pntsd;
1052 }
1053
1054 aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL);
1055 if (!aces_base) {
1056 rc = -ENOMEM;
1057 goto free_parent_pntsd;
1058 }
1059
1060 aces = (struct smb_ace *)aces_base;
1061 parent_aces = (struct smb_ace *)((char *)parent_pdacl +
1062 sizeof(struct smb_acl));
1063 aces_size = acl_len - sizeof(struct smb_acl);
1064
1065 if (pntsd_type & DACL_AUTO_INHERITED)
1066 inherited_flags = INHERITED_ACE;
1067
1068 for (i = 0; i < num_aces; i++) {
1069 int pace_size;
1070
1071 if (offsetof(struct smb_ace, access_req) > aces_size)
1072 break;
1073
1074 pace_size = le16_to_cpu(parent_aces->size);
1075 if (pace_size > aces_size)
1076 break;
1077
1078 aces_size -= pace_size;
1079
1080 flags = parent_aces->flags;
1081 if (!smb_inherit_flags(flags, is_dir))
1082 goto pass;
1083 if (is_dir) {
1084 flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE);
1085 if (!(flags & CONTAINER_INHERIT_ACE))
1086 flags |= INHERIT_ONLY_ACE;
1087 if (flags & NO_PROPAGATE_INHERIT_ACE)
1088 flags = 0;
1089 } else {
1090 flags = 0;
1091 }
1092
1093 if (!compare_sids(&creator_owner, &parent_aces->sid)) {
1094 creator = &creator_owner;
1095 id_to_sid(uid, SIDOWNER, &owner_sid);
1096 psid = &owner_sid;
1097 } else if (!compare_sids(&creator_group, &parent_aces->sid)) {
1098 creator = &creator_group;
1099 id_to_sid(gid, SIDUNIX_GROUP, &group_sid);
1100 psid = &group_sid;
1101 } else {
1102 creator = NULL;
1103 psid = &parent_aces->sid;
1104 }
1105
1106 if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) {
1107 smb_set_ace(aces, psid, parent_aces->type, inherited_flags,
1108 parent_aces->access_req);
1109 nt_size += le16_to_cpu(aces->size);
1110 ace_cnt++;
1111 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1112 flags |= INHERIT_ONLY_ACE;
1113 psid = creator;
1114 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) {
1115 psid = &parent_aces->sid;
1116 }
1117
1118 smb_set_ace(aces, psid, parent_aces->type, flags | inherited_flags,
1119 parent_aces->access_req);
1120 nt_size += le16_to_cpu(aces->size);
1121 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1122 ace_cnt++;
1123 pass:
1124 parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size);
1125 }
1126
1127 if (nt_size > 0) {
1128 struct smb_ntsd *pntsd;
1129 struct smb_acl *pdacl;
1130 struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL;
1131 int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size;
1132 int pntsd_alloc_size;
1133
1134 if (parent_pntsd->osidoffset) {
1135 powner_sid = (struct smb_sid *)((char *)parent_pntsd +
1136 le32_to_cpu(parent_pntsd->osidoffset));
1137 powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4);
1138 }
1139 if (parent_pntsd->gsidoffset) {
1140 pgroup_sid = (struct smb_sid *)((char *)parent_pntsd +
1141 le32_to_cpu(parent_pntsd->gsidoffset));
1142 pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4);
1143 }
1144
1145 pntsd_alloc_size = sizeof(struct smb_ntsd) + powner_sid_size +
1146 pgroup_sid_size + sizeof(struct smb_acl) + nt_size;
1147
1148 pntsd = kzalloc(pntsd_alloc_size, GFP_KERNEL);
1149 if (!pntsd) {
1150 rc = -ENOMEM;
1151 goto free_aces_base;
1152 }
1153
1154 pntsd->revision = cpu_to_le16(1);
1155 pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT);
1156 if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED)
1157 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
1158 pntsd_size = sizeof(struct smb_ntsd);
1159 pntsd->osidoffset = parent_pntsd->osidoffset;
1160 pntsd->gsidoffset = parent_pntsd->gsidoffset;
1161 pntsd->dacloffset = parent_pntsd->dacloffset;
1162
1163 if ((u64)le32_to_cpu(pntsd->osidoffset) + powner_sid_size >
1164 pntsd_alloc_size) {
1165 rc = -EINVAL;
1166 kfree(pntsd);
1167 goto free_aces_base;
1168 }
1169
1170 if ((u64)le32_to_cpu(pntsd->gsidoffset) + pgroup_sid_size >
1171 pntsd_alloc_size) {
1172 rc = -EINVAL;
1173 kfree(pntsd);
1174 goto free_aces_base;
1175 }
1176
1177 if ((u64)le32_to_cpu(pntsd->dacloffset) + sizeof(struct smb_acl) + nt_size >
1178 pntsd_alloc_size) {
1179 rc = -EINVAL;
1180 kfree(pntsd);
1181 goto free_aces_base;
1182 }
1183
1184 if (pntsd->osidoffset) {
1185 struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd +
1186 le32_to_cpu(pntsd->osidoffset));
1187 memcpy(owner_sid, powner_sid, powner_sid_size);
1188 pntsd_size += powner_sid_size;
1189 }
1190
1191 if (pntsd->gsidoffset) {
1192 struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd +
1193 le32_to_cpu(pntsd->gsidoffset));
1194 memcpy(group_sid, pgroup_sid, pgroup_sid_size);
1195 pntsd_size += pgroup_sid_size;
1196 }
1197
1198 if (pntsd->dacloffset) {
1199 struct smb_ace *pace;
1200
1201 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1202 pdacl->revision = cpu_to_le16(2);
1203 pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size);
1204 pdacl->num_aces = cpu_to_le32(ace_cnt);
1205 pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1206 memcpy(pace, aces_base, nt_size);
1207 pntsd_size += sizeof(struct smb_acl) + nt_size;
1208 }
1209
1210 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, pntsd_size, false);
1211 kfree(pntsd);
1212 }
1213
1214 free_aces_base:
1215 kfree(aces_base);
1216 free_parent_pntsd:
1217 kfree(parent_pntsd);
1218 return rc;
1219 }
1220
smb_inherit_flags(int flags,bool is_dir)1221 bool smb_inherit_flags(int flags, bool is_dir)
1222 {
1223 if (!is_dir)
1224 return (flags & OBJECT_INHERIT_ACE) != 0;
1225
1226 if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE))
1227 return true;
1228
1229 if (flags & CONTAINER_INHERIT_ACE)
1230 return true;
1231 return false;
1232 }
1233
smb_check_perm_dacl(struct ksmbd_conn * conn,const struct path * path,__le32 * pdaccess,int uid)1234 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
1235 __le32 *pdaccess, int uid)
1236 {
1237 struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1238 struct smb_ntsd *pntsd = NULL;
1239 struct smb_acl *pdacl;
1240 struct posix_acl *posix_acls;
1241 int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size, dacl_offset;
1242 struct smb_sid sid;
1243 int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
1244 struct smb_ace *ace;
1245 int i, found = 0;
1246 unsigned int access_bits = 0;
1247 struct smb_ace *others_ace = NULL;
1248 struct posix_acl_entry *pa_entry;
1249 unsigned int sid_type = SIDOWNER;
1250 unsigned short ace_size;
1251
1252 ksmbd_debug(SMB, "check permission using windows acl\n");
1253 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1254 path->dentry, &pntsd);
1255 if (pntsd_size <= 0 || !pntsd)
1256 goto err_out;
1257
1258 dacl_offset = le32_to_cpu(pntsd->dacloffset);
1259 if (!dacl_offset ||
1260 (dacl_offset + sizeof(struct smb_acl) > pntsd_size))
1261 goto err_out;
1262
1263 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1264 acl_size = pntsd_size - dacl_offset;
1265 pdacl_size = le16_to_cpu(pdacl->size);
1266
1267 if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl))
1268 goto err_out;
1269
1270 if (!pdacl->num_aces) {
1271 if (!(pdacl_size - sizeof(struct smb_acl)) &&
1272 *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) {
1273 rc = -EACCES;
1274 goto err_out;
1275 }
1276 goto err_out;
1277 }
1278
1279 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
1280 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1281 DELETE;
1282
1283 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1284 aces_size = acl_size - sizeof(struct smb_acl);
1285 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1286 if (offsetof(struct smb_ace, access_req) > aces_size)
1287 break;
1288 ace_size = le16_to_cpu(ace->size);
1289 if (ace_size > aces_size)
1290 break;
1291 aces_size -= ace_size;
1292 granted |= le32_to_cpu(ace->access_req);
1293 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1294 }
1295
1296 if (!pdacl->num_aces)
1297 granted = GENERIC_ALL_FLAGS;
1298 }
1299
1300 if (!uid)
1301 sid_type = SIDUNIX_USER;
1302 id_to_sid(uid, sid_type, &sid);
1303
1304 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1305 aces_size = acl_size - sizeof(struct smb_acl);
1306 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1307 if (offsetof(struct smb_ace, access_req) > aces_size)
1308 break;
1309 ace_size = le16_to_cpu(ace->size);
1310 if (ace_size > aces_size)
1311 break;
1312 aces_size -= ace_size;
1313
1314 if (!compare_sids(&sid, &ace->sid) ||
1315 !compare_sids(&sid_unix_NFS_mode, &ace->sid)) {
1316 found = 1;
1317 break;
1318 }
1319 if (!compare_sids(&sid_everyone, &ace->sid))
1320 others_ace = ace;
1321
1322 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1323 }
1324
1325 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
1326 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1327 DELETE;
1328
1329 granted |= le32_to_cpu(ace->access_req);
1330
1331 if (!pdacl->num_aces)
1332 granted = GENERIC_ALL_FLAGS;
1333 }
1334
1335 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
1336 posix_acls = get_inode_acl(d_inode(path->dentry), ACL_TYPE_ACCESS);
1337 if (!IS_ERR_OR_NULL(posix_acls) && !found) {
1338 unsigned int id = -1;
1339
1340 pa_entry = posix_acls->a_entries;
1341 for (i = 0; i < posix_acls->a_count; i++, pa_entry++) {
1342 if (pa_entry->e_tag == ACL_USER)
1343 id = posix_acl_uid_translate(idmap, pa_entry);
1344 else if (pa_entry->e_tag == ACL_GROUP)
1345 id = posix_acl_gid_translate(idmap, pa_entry);
1346 else
1347 continue;
1348
1349 if (id == uid) {
1350 mode_to_access_flags(pa_entry->e_perm,
1351 0777,
1352 &access_bits);
1353 if (!access_bits)
1354 access_bits =
1355 SET_MINIMUM_RIGHTS;
1356 posix_acl_release(posix_acls);
1357 goto check_access_bits;
1358 }
1359 }
1360 }
1361 if (!IS_ERR_OR_NULL(posix_acls))
1362 posix_acl_release(posix_acls);
1363 }
1364
1365 if (!found) {
1366 if (others_ace) {
1367 ace = others_ace;
1368 } else {
1369 ksmbd_debug(SMB, "Can't find corresponding sid\n");
1370 rc = -EACCES;
1371 goto err_out;
1372 }
1373 }
1374
1375 switch (ace->type) {
1376 case ACCESS_ALLOWED_ACE_TYPE:
1377 access_bits = le32_to_cpu(ace->access_req);
1378 break;
1379 case ACCESS_DENIED_ACE_TYPE:
1380 case ACCESS_DENIED_CALLBACK_ACE_TYPE:
1381 access_bits = le32_to_cpu(~ace->access_req);
1382 break;
1383 }
1384
1385 check_access_bits:
1386 if (granted &
1387 ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) {
1388 ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n",
1389 granted, le32_to_cpu(ace->access_req));
1390 rc = -EACCES;
1391 goto err_out;
1392 }
1393
1394 *pdaccess = cpu_to_le32(granted);
1395 err_out:
1396 kfree(pntsd);
1397 return rc;
1398 }
1399
set_info_sec(struct ksmbd_conn * conn,struct ksmbd_tree_connect * tcon,const struct path * path,struct smb_ntsd * pntsd,int ntsd_len,bool type_check,bool get_write)1400 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
1401 const struct path *path, struct smb_ntsd *pntsd, int ntsd_len,
1402 bool type_check, bool get_write)
1403 {
1404 int rc;
1405 struct smb_fattr fattr = {{0}};
1406 struct inode *inode = d_inode(path->dentry);
1407 struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1408 struct iattr newattrs;
1409
1410 fattr.cf_uid = INVALID_UID;
1411 fattr.cf_gid = INVALID_GID;
1412 fattr.cf_mode = inode->i_mode;
1413
1414 rc = parse_sec_desc(idmap, pntsd, ntsd_len, &fattr);
1415 if (rc)
1416 goto out;
1417
1418 newattrs.ia_valid = ATTR_CTIME;
1419 if (!uid_eq(fattr.cf_uid, INVALID_UID)) {
1420 newattrs.ia_valid |= ATTR_UID;
1421 newattrs.ia_uid = fattr.cf_uid;
1422 }
1423 if (!gid_eq(fattr.cf_gid, INVALID_GID)) {
1424 newattrs.ia_valid |= ATTR_GID;
1425 newattrs.ia_gid = fattr.cf_gid;
1426 }
1427 newattrs.ia_valid |= ATTR_MODE;
1428 newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
1429
1430 ksmbd_vfs_remove_acl_xattrs(idmap, path);
1431 /* Update posix acls */
1432 if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) {
1433 rc = set_posix_acl(idmap, path->dentry,
1434 ACL_TYPE_ACCESS, fattr.cf_acls);
1435 if (rc < 0)
1436 ksmbd_debug(SMB,
1437 "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
1438 rc);
1439 if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) {
1440 rc = set_posix_acl(idmap, path->dentry,
1441 ACL_TYPE_DEFAULT, fattr.cf_dacls);
1442 if (rc)
1443 ksmbd_debug(SMB,
1444 "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n",
1445 rc);
1446 }
1447 }
1448
1449 inode_lock(inode);
1450 rc = notify_change(idmap, path->dentry, &newattrs, NULL);
1451 inode_unlock(inode);
1452 if (rc)
1453 goto out;
1454
1455 /* Check it only calling from SD BUFFER context */
1456 if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT))
1457 goto out;
1458
1459 if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) {
1460 /* Update WinACL in xattr */
1461 ksmbd_vfs_remove_sd_xattrs(idmap, path);
1462 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, ntsd_len,
1463 get_write);
1464 }
1465
1466 out:
1467 posix_acl_release(fattr.cf_acls);
1468 posix_acl_release(fattr.cf_dacls);
1469 return rc;
1470 }
1471
ksmbd_init_domain(u32 * sub_auth)1472 void ksmbd_init_domain(u32 *sub_auth)
1473 {
1474 int i;
1475
1476 memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid));
1477 for (i = 0; i < 3; ++i)
1478 server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]);
1479 }
1480