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, KSMBD_DEFAULT_GFP);
349 if (!state->users)
350 return -ENOMEM;
351 state->groups = kzalloc(alloc, KSMBD_DEFAULT_GFP);
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 > ULONG_MAX / sizeof(struct smb_ace *))
402 return;
403
404 ret = init_acl_state(&acl_state, num_aces);
405 if (ret)
406 return;
407 ret = init_acl_state(&default_acl_state, num_aces);
408 if (ret) {
409 free_acl_state(&acl_state);
410 return;
411 }
412
413 ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), KSMBD_DEFAULT_GFP);
414 if (!ppace) {
415 free_acl_state(&default_acl_state);
416 free_acl_state(&acl_state);
417 return;
418 }
419
420 /*
421 * reset rwx permissions for user/group/other.
422 * Also, if num_aces is 0 i.e. DACL has no ACEs,
423 * user/group/other have no permissions
424 */
425 for (i = 0; i < num_aces; ++i) {
426 if (end_of_acl - acl_base < acl_size)
427 break;
428
429 ppace[i] = (struct smb_ace *)(acl_base + acl_size);
430 acl_base = (char *)ppace[i];
431 acl_size = offsetof(struct smb_ace, sid) +
432 offsetof(struct smb_sid, sub_auth);
433
434 if (end_of_acl - acl_base < acl_size ||
435 ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES ||
436 (end_of_acl - acl_base <
437 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) ||
438 (le16_to_cpu(ppace[i]->size) <
439 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth))
440 break;
441
442 acl_size = le16_to_cpu(ppace[i]->size);
443 ppace[i]->access_req =
444 smb_map_generic_desired_access(ppace[i]->access_req);
445
446 if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) {
447 fattr->cf_mode =
448 le32_to_cpu(ppace[i]->sid.sub_auth[2]);
449 break;
450 } else if (!compare_sids(&ppace[i]->sid, pownersid)) {
451 acl_mode = access_flags_to_mode(fattr,
452 ppace[i]->access_req,
453 ppace[i]->type);
454 acl_mode &= 0700;
455
456 if (!owner_found) {
457 mode &= ~(0700);
458 mode |= acl_mode;
459 }
460 owner_found = true;
461 } else if (!compare_sids(&ppace[i]->sid, pgrpsid) ||
462 ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] ==
463 DOMAIN_USER_RID_LE) {
464 acl_mode = access_flags_to_mode(fattr,
465 ppace[i]->access_req,
466 ppace[i]->type);
467 acl_mode &= 0070;
468 if (!group_found) {
469 mode &= ~(0070);
470 mode |= acl_mode;
471 }
472 group_found = true;
473 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) {
474 acl_mode = access_flags_to_mode(fattr,
475 ppace[i]->access_req,
476 ppace[i]->type);
477 acl_mode &= 0007;
478 if (!others_found) {
479 mode &= ~(0007);
480 mode |= acl_mode;
481 }
482 others_found = true;
483 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) {
484 continue;
485 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) {
486 continue;
487 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) {
488 continue;
489 } else {
490 struct smb_fattr temp_fattr;
491
492 acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
493 ppace[i]->type);
494 temp_fattr.cf_uid = INVALID_UID;
495 ret = sid_to_id(idmap, &ppace[i]->sid, SIDOWNER, &temp_fattr);
496 if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) {
497 pr_err("%s: Error %d mapping Owner SID to uid\n",
498 __func__, ret);
499 continue;
500 }
501
502 acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
503 acl_state.users->aces[acl_state.users->n].uid =
504 temp_fattr.cf_uid;
505 acl_state.users->aces[acl_state.users->n++].perms.allow =
506 ((acl_mode & 0700) >> 6) | 0004;
507 default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
508 default_acl_state.users->aces[default_acl_state.users->n].uid =
509 temp_fattr.cf_uid;
510 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
511 ((acl_mode & 0700) >> 6) | 0004;
512 }
513 }
514 kfree(ppace);
515
516 if (owner_found) {
517 /* The owner must be set to at least read-only. */
518 acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
519 acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid;
520 acl_state.users->aces[acl_state.users->n++].perms.allow =
521 ((mode & 0700) >> 6) | 0004;
522 default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
523 default_acl_state.users->aces[default_acl_state.users->n].uid =
524 fattr->cf_uid;
525 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
526 ((mode & 0700) >> 6) | 0004;
527 }
528
529 if (group_found) {
530 acl_state.group.allow = (mode & 0070) >> 3;
531 acl_state.groups->aces[acl_state.groups->n].gid =
532 fattr->cf_gid;
533 acl_state.groups->aces[acl_state.groups->n++].perms.allow =
534 (mode & 0070) >> 3;
535 default_acl_state.group.allow = (mode & 0070) >> 3;
536 default_acl_state.groups->aces[default_acl_state.groups->n].gid =
537 fattr->cf_gid;
538 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow =
539 (mode & 0070) >> 3;
540 }
541
542 if (others_found) {
543 fattr->cf_mode &= ~(0007);
544 fattr->cf_mode |= mode & 0007;
545
546 acl_state.other.allow = mode & 0007;
547 default_acl_state.other.allow = mode & 0007;
548 }
549
550 if (acl_state.users->n || acl_state.groups->n) {
551 acl_state.mask.allow = 0x07;
552
553 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
554 fattr->cf_acls =
555 posix_acl_alloc(acl_state.users->n +
556 acl_state.groups->n + 4, KSMBD_DEFAULT_GFP);
557 if (fattr->cf_acls) {
558 cf_pace = fattr->cf_acls->a_entries;
559 posix_state_to_acl(&acl_state, cf_pace);
560 }
561 }
562 }
563
564 if (default_acl_state.users->n || default_acl_state.groups->n) {
565 default_acl_state.mask.allow = 0x07;
566
567 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
568 fattr->cf_dacls =
569 posix_acl_alloc(default_acl_state.users->n +
570 default_acl_state.groups->n + 4, KSMBD_DEFAULT_GFP);
571 if (fattr->cf_dacls) {
572 cf_pdace = fattr->cf_dacls->a_entries;
573 posix_state_to_acl(&default_acl_state, cf_pdace);
574 }
575 }
576 }
577 free_acl_state(&acl_state);
578 free_acl_state(&default_acl_state);
579 }
580
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)581 static void set_posix_acl_entries_dacl(struct mnt_idmap *idmap,
582 struct smb_ace *pndace,
583 struct smb_fattr *fattr, u32 *num_aces,
584 u16 *size, u32 nt_aces_num)
585 {
586 struct posix_acl_entry *pace;
587 struct smb_sid *sid;
588 struct smb_ace *ntace;
589 int i, j;
590
591 if (!fattr->cf_acls)
592 goto posix_default_acl;
593
594 pace = fattr->cf_acls->a_entries;
595 for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) {
596 int flags = 0;
597
598 sid = kmalloc(sizeof(struct smb_sid), KSMBD_DEFAULT_GFP);
599 if (!sid)
600 break;
601
602 if (pace->e_tag == ACL_USER) {
603 uid_t uid;
604 unsigned int sid_type = SIDOWNER;
605
606 uid = posix_acl_uid_translate(idmap, pace);
607 if (!uid)
608 sid_type = SIDUNIX_USER;
609 id_to_sid(uid, sid_type, sid);
610 } else if (pace->e_tag == ACL_GROUP) {
611 gid_t gid;
612
613 gid = posix_acl_gid_translate(idmap, pace);
614 id_to_sid(gid, SIDUNIX_GROUP, sid);
615 } else if (pace->e_tag == ACL_OTHER && !nt_aces_num) {
616 smb_copy_sid(sid, &sid_everyone);
617 } else {
618 kfree(sid);
619 continue;
620 }
621 ntace = pndace;
622 for (j = 0; j < nt_aces_num; j++) {
623 if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] ==
624 sid->sub_auth[sid->num_subauth - 1])
625 goto pass_same_sid;
626 ntace = (struct smb_ace *)((char *)ntace +
627 le16_to_cpu(ntace->size));
628 }
629
630 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER)
631 flags = 0x03;
632
633 ntace = (struct smb_ace *)((char *)pndace + *size);
634 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags,
635 pace->e_perm, 0777);
636 (*num_aces)++;
637 if (pace->e_tag == ACL_USER)
638 ntace->access_req |=
639 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
640
641 if (S_ISDIR(fattr->cf_mode) &&
642 (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) {
643 ntace = (struct smb_ace *)((char *)pndace + *size);
644 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED,
645 0x03, pace->e_perm, 0777);
646 (*num_aces)++;
647 if (pace->e_tag == ACL_USER)
648 ntace->access_req |=
649 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
650 }
651
652 pass_same_sid:
653 kfree(sid);
654 }
655
656 if (nt_aces_num)
657 return;
658
659 posix_default_acl:
660 if (!fattr->cf_dacls)
661 return;
662
663 pace = fattr->cf_dacls->a_entries;
664 for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) {
665 sid = kmalloc(sizeof(struct smb_sid), KSMBD_DEFAULT_GFP);
666 if (!sid)
667 break;
668
669 if (pace->e_tag == ACL_USER) {
670 uid_t uid;
671
672 uid = posix_acl_uid_translate(idmap, pace);
673 id_to_sid(uid, SIDCREATOR_OWNER, sid);
674 } else if (pace->e_tag == ACL_GROUP) {
675 gid_t gid;
676
677 gid = posix_acl_gid_translate(idmap, pace);
678 id_to_sid(gid, SIDCREATOR_GROUP, sid);
679 } else {
680 kfree(sid);
681 continue;
682 }
683
684 ntace = (struct smb_ace *)((char *)pndace + *size);
685 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b,
686 pace->e_perm, 0777);
687 (*num_aces)++;
688 if (pace->e_tag == ACL_USER)
689 ntace->access_req |=
690 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
691 kfree(sid);
692 }
693 }
694
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)695 static void set_ntacl_dacl(struct mnt_idmap *idmap,
696 struct smb_acl *pndacl,
697 struct smb_acl *nt_dacl,
698 unsigned int aces_size,
699 const struct smb_sid *pownersid,
700 const struct smb_sid *pgrpsid,
701 struct smb_fattr *fattr)
702 {
703 struct smb_ace *ntace, *pndace;
704 int nt_num_aces = le32_to_cpu(nt_dacl->num_aces), num_aces = 0;
705 unsigned short size = 0;
706 int i;
707
708 pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
709 if (nt_num_aces) {
710 ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl));
711 for (i = 0; i < nt_num_aces; i++) {
712 unsigned short nt_ace_size;
713
714 if (offsetof(struct smb_ace, access_req) > aces_size)
715 break;
716
717 nt_ace_size = le16_to_cpu(ntace->size);
718 if (nt_ace_size > aces_size)
719 break;
720
721 memcpy((char *)pndace + size, ntace, nt_ace_size);
722 size += nt_ace_size;
723 aces_size -= nt_ace_size;
724 ntace = (struct smb_ace *)((char *)ntace + nt_ace_size);
725 num_aces++;
726 }
727 }
728
729 set_posix_acl_entries_dacl(idmap, pndace, fattr,
730 &num_aces, &size, nt_num_aces);
731 pndacl->num_aces = cpu_to_le32(num_aces);
732 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
733 }
734
set_mode_dacl(struct mnt_idmap * idmap,struct smb_acl * pndacl,struct smb_fattr * fattr)735 static void set_mode_dacl(struct mnt_idmap *idmap,
736 struct smb_acl *pndacl, struct smb_fattr *fattr)
737 {
738 struct smb_ace *pace, *pndace;
739 u32 num_aces = 0;
740 u16 size = 0, ace_size = 0;
741 uid_t uid;
742 const struct smb_sid *sid;
743
744 pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
745
746 if (fattr->cf_acls) {
747 set_posix_acl_entries_dacl(idmap, pndace, fattr,
748 &num_aces, &size, num_aces);
749 goto out;
750 }
751
752 /* owner RID */
753 uid = from_kuid(&init_user_ns, fattr->cf_uid);
754 if (uid)
755 sid = &server_conf.domain_sid;
756 else
757 sid = &sid_unix_users;
758 ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0,
759 fattr->cf_mode, 0700);
760 pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid);
761 pace->size = cpu_to_le16(ace_size + 4);
762 size += le16_to_cpu(pace->size);
763 pace = (struct smb_ace *)((char *)pndace + size);
764
765 /* Group RID */
766 ace_size = fill_ace_for_sid(pace, &sid_unix_groups,
767 ACCESS_ALLOWED, 0, fattr->cf_mode, 0070);
768 pace->sid.sub_auth[pace->sid.num_subauth++] =
769 cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid));
770 pace->size = cpu_to_le16(ace_size + 4);
771 size += le16_to_cpu(pace->size);
772 pace = (struct smb_ace *)((char *)pndace + size);
773 num_aces = 3;
774
775 if (S_ISDIR(fattr->cf_mode)) {
776 pace = (struct smb_ace *)((char *)pndace + size);
777
778 /* creator owner */
779 size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED,
780 0x0b, fattr->cf_mode, 0700);
781 pace = (struct smb_ace *)((char *)pndace + size);
782
783 /* creator group */
784 size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED,
785 0x0b, fattr->cf_mode, 0070);
786 pace = (struct smb_ace *)((char *)pndace + size);
787 num_aces = 5;
788 }
789
790 /* other */
791 size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0,
792 fattr->cf_mode, 0007);
793
794 out:
795 pndacl->num_aces = cpu_to_le32(num_aces);
796 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
797 }
798
parse_sid(struct smb_sid * psid,char * end_of_acl)799 static int parse_sid(struct smb_sid *psid, char *end_of_acl)
800 {
801 /*
802 * validate that we do not go past end of ACL - sid must be at least 8
803 * bytes long (assuming no sub-auths - e.g. the null SID
804 */
805 if (end_of_acl < (char *)psid + 8) {
806 pr_err("ACL too small to parse SID %p\n", psid);
807 return -EINVAL;
808 }
809
810 return 0;
811 }
812
813 /* Convert CIFS ACL to POSIX form */
parse_sec_desc(struct mnt_idmap * idmap,struct smb_ntsd * pntsd,int acl_len,struct smb_fattr * fattr)814 int parse_sec_desc(struct mnt_idmap *idmap, struct smb_ntsd *pntsd,
815 int acl_len, struct smb_fattr *fattr)
816 {
817 int rc = 0;
818 struct smb_sid *owner_sid_ptr, *group_sid_ptr;
819 struct smb_acl *dacl_ptr; /* no need for SACL ptr */
820 char *end_of_acl = ((char *)pntsd) + acl_len;
821 __u32 dacloffset;
822 int pntsd_type;
823
824 if (!pntsd)
825 return -EIO;
826
827 if (acl_len < sizeof(struct smb_ntsd))
828 return -EINVAL;
829
830 owner_sid_ptr = (struct smb_sid *)((char *)pntsd +
831 le32_to_cpu(pntsd->osidoffset));
832 group_sid_ptr = (struct smb_sid *)((char *)pntsd +
833 le32_to_cpu(pntsd->gsidoffset));
834 dacloffset = le32_to_cpu(pntsd->dacloffset);
835 dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset);
836 ksmbd_debug(SMB,
837 "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n",
838 pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
839 le32_to_cpu(pntsd->gsidoffset),
840 le32_to_cpu(pntsd->sacloffset), dacloffset);
841
842 pntsd_type = le16_to_cpu(pntsd->type);
843 if (!(pntsd_type & DACL_PRESENT)) {
844 ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n");
845 return rc;
846 }
847
848 pntsd->type = cpu_to_le16(DACL_PRESENT);
849
850 if (pntsd->osidoffset) {
851 rc = parse_sid(owner_sid_ptr, end_of_acl);
852 if (rc) {
853 pr_err("%s: Error %d parsing Owner SID\n", __func__, rc);
854 return rc;
855 }
856
857 rc = sid_to_id(idmap, owner_sid_ptr, SIDOWNER, fattr);
858 if (rc) {
859 pr_err("%s: Error %d mapping Owner SID to uid\n",
860 __func__, rc);
861 owner_sid_ptr = NULL;
862 }
863 }
864
865 if (pntsd->gsidoffset) {
866 rc = parse_sid(group_sid_ptr, end_of_acl);
867 if (rc) {
868 pr_err("%s: Error %d mapping Owner SID to gid\n",
869 __func__, rc);
870 return rc;
871 }
872 rc = sid_to_id(idmap, group_sid_ptr, SIDUNIX_GROUP, fattr);
873 if (rc) {
874 pr_err("%s: Error %d mapping Group SID to gid\n",
875 __func__, rc);
876 group_sid_ptr = NULL;
877 }
878 }
879
880 if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) ==
881 (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ))
882 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
883 if (pntsd_type & DACL_PROTECTED)
884 pntsd->type |= cpu_to_le16(DACL_PROTECTED);
885
886 if (dacloffset) {
887 parse_dacl(idmap, dacl_ptr, end_of_acl,
888 owner_sid_ptr, group_sid_ptr, fattr);
889 }
890
891 return 0;
892 }
893
894 /* 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)895 int build_sec_desc(struct mnt_idmap *idmap,
896 struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
897 int ppntsd_size, int addition_info, __u32 *secdesclen,
898 struct smb_fattr *fattr)
899 {
900 int rc = 0;
901 __u32 offset;
902 struct smb_sid *owner_sid_ptr, *group_sid_ptr;
903 struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr;
904 struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */
905 uid_t uid;
906 gid_t gid;
907 unsigned int sid_type = SIDOWNER;
908
909 nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), KSMBD_DEFAULT_GFP);
910 if (!nowner_sid_ptr)
911 return -ENOMEM;
912
913 uid = from_kuid(&init_user_ns, fattr->cf_uid);
914 if (!uid)
915 sid_type = SIDUNIX_USER;
916 id_to_sid(uid, sid_type, nowner_sid_ptr);
917
918 ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), KSMBD_DEFAULT_GFP);
919 if (!ngroup_sid_ptr) {
920 kfree(nowner_sid_ptr);
921 return -ENOMEM;
922 }
923
924 gid = from_kgid(&init_user_ns, fattr->cf_gid);
925 id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr);
926
927 offset = sizeof(struct smb_ntsd);
928 pntsd->sacloffset = 0;
929 pntsd->revision = cpu_to_le16(1);
930 pntsd->type = cpu_to_le16(SELF_RELATIVE);
931 if (ppntsd)
932 pntsd->type |= ppntsd->type;
933
934 if (addition_info & OWNER_SECINFO) {
935 pntsd->osidoffset = cpu_to_le32(offset);
936 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
937 smb_copy_sid(owner_sid_ptr, nowner_sid_ptr);
938 offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4);
939 }
940
941 if (addition_info & GROUP_SECINFO) {
942 pntsd->gsidoffset = cpu_to_le32(offset);
943 group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
944 smb_copy_sid(group_sid_ptr, ngroup_sid_ptr);
945 offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4);
946 }
947
948 if (addition_info & DACL_SECINFO) {
949 pntsd->type |= cpu_to_le16(DACL_PRESENT);
950 dacl_ptr = (struct smb_acl *)((char *)pntsd + offset);
951 dacl_ptr->revision = cpu_to_le16(2);
952 dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl));
953 dacl_ptr->num_aces = 0;
954
955 if (!ppntsd) {
956 set_mode_dacl(idmap, dacl_ptr, fattr);
957 } else {
958 struct smb_acl *ppdacl_ptr;
959 unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset);
960 int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset;
961
962 if (!dacl_offset ||
963 (dacl_offset + sizeof(struct smb_acl) > ppntsd_size))
964 goto out;
965
966 ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset);
967 ppdacl_size = le16_to_cpu(ppdacl_ptr->size);
968 if (ppdacl_size > ntacl_size ||
969 ppdacl_size < sizeof(struct smb_acl))
970 goto out;
971
972 set_ntacl_dacl(idmap, dacl_ptr, ppdacl_ptr,
973 ntacl_size - sizeof(struct smb_acl),
974 nowner_sid_ptr, ngroup_sid_ptr,
975 fattr);
976 }
977 pntsd->dacloffset = cpu_to_le32(offset);
978 offset += le16_to_cpu(dacl_ptr->size);
979 }
980
981 out:
982 kfree(nowner_sid_ptr);
983 kfree(ngroup_sid_ptr);
984 *secdesclen = offset;
985 return rc;
986 }
987
smb_set_ace(struct smb_ace * ace,const struct smb_sid * sid,u8 type,u8 flags,__le32 access_req)988 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type,
989 u8 flags, __le32 access_req)
990 {
991 ace->type = type;
992 ace->flags = flags;
993 ace->access_req = access_req;
994 smb_copy_sid(&ace->sid, sid);
995 ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + (sid->num_subauth * 4));
996 }
997
smb_inherit_dacl(struct ksmbd_conn * conn,const struct path * path,unsigned int uid,unsigned int gid)998 int smb_inherit_dacl(struct ksmbd_conn *conn,
999 const struct path *path,
1000 unsigned int uid, unsigned int gid)
1001 {
1002 const struct smb_sid *psid, *creator = NULL;
1003 struct smb_ace *parent_aces, *aces;
1004 struct smb_acl *parent_pdacl;
1005 struct smb_ntsd *parent_pntsd = NULL;
1006 struct smb_sid owner_sid, group_sid;
1007 struct dentry *parent = path->dentry->d_parent;
1008 struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1009 int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size;
1010 int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size;
1011 char *aces_base;
1012 bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
1013
1014 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1015 parent, &parent_pntsd);
1016 if (pntsd_size <= 0)
1017 return -ENOENT;
1018 dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
1019 if (!dacloffset || (dacloffset + sizeof(struct smb_acl) > pntsd_size)) {
1020 rc = -EINVAL;
1021 goto free_parent_pntsd;
1022 }
1023
1024 parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset);
1025 acl_len = pntsd_size - dacloffset;
1026 num_aces = le32_to_cpu(parent_pdacl->num_aces);
1027 pntsd_type = le16_to_cpu(parent_pntsd->type);
1028 pdacl_size = le16_to_cpu(parent_pdacl->size);
1029
1030 if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) {
1031 rc = -EINVAL;
1032 goto free_parent_pntsd;
1033 }
1034
1035 aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2,
1036 KSMBD_DEFAULT_GFP);
1037 if (!aces_base) {
1038 rc = -ENOMEM;
1039 goto free_parent_pntsd;
1040 }
1041
1042 aces = (struct smb_ace *)aces_base;
1043 parent_aces = (struct smb_ace *)((char *)parent_pdacl +
1044 sizeof(struct smb_acl));
1045 aces_size = acl_len - sizeof(struct smb_acl);
1046
1047 if (pntsd_type & DACL_AUTO_INHERITED)
1048 inherited_flags = INHERITED_ACE;
1049
1050 for (i = 0; i < num_aces; i++) {
1051 int pace_size;
1052
1053 if (offsetof(struct smb_ace, access_req) > aces_size)
1054 break;
1055
1056 pace_size = le16_to_cpu(parent_aces->size);
1057 if (pace_size > aces_size)
1058 break;
1059
1060 aces_size -= pace_size;
1061
1062 flags = parent_aces->flags;
1063 if (!smb_inherit_flags(flags, is_dir))
1064 goto pass;
1065 if (is_dir) {
1066 flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE);
1067 if (!(flags & CONTAINER_INHERIT_ACE))
1068 flags |= INHERIT_ONLY_ACE;
1069 if (flags & NO_PROPAGATE_INHERIT_ACE)
1070 flags = 0;
1071 } else {
1072 flags = 0;
1073 }
1074
1075 if (!compare_sids(&creator_owner, &parent_aces->sid)) {
1076 creator = &creator_owner;
1077 id_to_sid(uid, SIDOWNER, &owner_sid);
1078 psid = &owner_sid;
1079 } else if (!compare_sids(&creator_group, &parent_aces->sid)) {
1080 creator = &creator_group;
1081 id_to_sid(gid, SIDUNIX_GROUP, &group_sid);
1082 psid = &group_sid;
1083 } else {
1084 creator = NULL;
1085 psid = &parent_aces->sid;
1086 }
1087
1088 if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) {
1089 smb_set_ace(aces, psid, parent_aces->type, inherited_flags,
1090 parent_aces->access_req);
1091 nt_size += le16_to_cpu(aces->size);
1092 ace_cnt++;
1093 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1094 flags |= INHERIT_ONLY_ACE;
1095 psid = creator;
1096 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) {
1097 psid = &parent_aces->sid;
1098 }
1099
1100 smb_set_ace(aces, psid, parent_aces->type, flags | inherited_flags,
1101 parent_aces->access_req);
1102 nt_size += le16_to_cpu(aces->size);
1103 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1104 ace_cnt++;
1105 pass:
1106 parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size);
1107 }
1108
1109 if (nt_size > 0) {
1110 struct smb_ntsd *pntsd;
1111 struct smb_acl *pdacl;
1112 struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL;
1113 int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size;
1114 int pntsd_alloc_size;
1115
1116 if (parent_pntsd->osidoffset) {
1117 powner_sid = (struct smb_sid *)((char *)parent_pntsd +
1118 le32_to_cpu(parent_pntsd->osidoffset));
1119 powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4);
1120 }
1121 if (parent_pntsd->gsidoffset) {
1122 pgroup_sid = (struct smb_sid *)((char *)parent_pntsd +
1123 le32_to_cpu(parent_pntsd->gsidoffset));
1124 pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4);
1125 }
1126
1127 pntsd_alloc_size = sizeof(struct smb_ntsd) + powner_sid_size +
1128 pgroup_sid_size + sizeof(struct smb_acl) + nt_size;
1129
1130 pntsd = kzalloc(pntsd_alloc_size, KSMBD_DEFAULT_GFP);
1131 if (!pntsd) {
1132 rc = -ENOMEM;
1133 goto free_aces_base;
1134 }
1135
1136 pntsd->revision = cpu_to_le16(1);
1137 pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT);
1138 if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED)
1139 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
1140 pntsd_size = sizeof(struct smb_ntsd);
1141 pntsd->osidoffset = parent_pntsd->osidoffset;
1142 pntsd->gsidoffset = parent_pntsd->gsidoffset;
1143 pntsd->dacloffset = parent_pntsd->dacloffset;
1144
1145 if ((u64)le32_to_cpu(pntsd->osidoffset) + powner_sid_size >
1146 pntsd_alloc_size) {
1147 rc = -EINVAL;
1148 kfree(pntsd);
1149 goto free_aces_base;
1150 }
1151
1152 if ((u64)le32_to_cpu(pntsd->gsidoffset) + pgroup_sid_size >
1153 pntsd_alloc_size) {
1154 rc = -EINVAL;
1155 kfree(pntsd);
1156 goto free_aces_base;
1157 }
1158
1159 if ((u64)le32_to_cpu(pntsd->dacloffset) + sizeof(struct smb_acl) + nt_size >
1160 pntsd_alloc_size) {
1161 rc = -EINVAL;
1162 kfree(pntsd);
1163 goto free_aces_base;
1164 }
1165
1166 if (pntsd->osidoffset) {
1167 struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd +
1168 le32_to_cpu(pntsd->osidoffset));
1169 memcpy(owner_sid, powner_sid, powner_sid_size);
1170 pntsd_size += powner_sid_size;
1171 }
1172
1173 if (pntsd->gsidoffset) {
1174 struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd +
1175 le32_to_cpu(pntsd->gsidoffset));
1176 memcpy(group_sid, pgroup_sid, pgroup_sid_size);
1177 pntsd_size += pgroup_sid_size;
1178 }
1179
1180 if (pntsd->dacloffset) {
1181 struct smb_ace *pace;
1182
1183 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1184 pdacl->revision = cpu_to_le16(2);
1185 pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size);
1186 pdacl->num_aces = cpu_to_le32(ace_cnt);
1187 pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1188 memcpy(pace, aces_base, nt_size);
1189 pntsd_size += sizeof(struct smb_acl) + nt_size;
1190 }
1191
1192 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, pntsd_size, false);
1193 kfree(pntsd);
1194 }
1195
1196 free_aces_base:
1197 kfree(aces_base);
1198 free_parent_pntsd:
1199 kfree(parent_pntsd);
1200 return rc;
1201 }
1202
smb_inherit_flags(int flags,bool is_dir)1203 bool smb_inherit_flags(int flags, bool is_dir)
1204 {
1205 if (!is_dir)
1206 return (flags & OBJECT_INHERIT_ACE) != 0;
1207
1208 if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE))
1209 return true;
1210
1211 if (flags & CONTAINER_INHERIT_ACE)
1212 return true;
1213 return false;
1214 }
1215
smb_check_perm_dacl(struct ksmbd_conn * conn,const struct path * path,__le32 * pdaccess,int uid)1216 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
1217 __le32 *pdaccess, int uid)
1218 {
1219 struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1220 struct smb_ntsd *pntsd = NULL;
1221 struct smb_acl *pdacl;
1222 struct posix_acl *posix_acls;
1223 int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size, dacl_offset;
1224 struct smb_sid sid;
1225 int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
1226 struct smb_ace *ace;
1227 int i, found = 0;
1228 unsigned int access_bits = 0;
1229 struct smb_ace *others_ace = NULL;
1230 struct posix_acl_entry *pa_entry;
1231 unsigned int sid_type = SIDOWNER;
1232 unsigned short ace_size;
1233
1234 ksmbd_debug(SMB, "check permission using windows acl\n");
1235 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1236 path->dentry, &pntsd);
1237 if (pntsd_size <= 0 || !pntsd)
1238 goto err_out;
1239
1240 dacl_offset = le32_to_cpu(pntsd->dacloffset);
1241 if (!dacl_offset ||
1242 (dacl_offset + sizeof(struct smb_acl) > pntsd_size))
1243 goto err_out;
1244
1245 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1246 acl_size = pntsd_size - dacl_offset;
1247 pdacl_size = le16_to_cpu(pdacl->size);
1248
1249 if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl))
1250 goto err_out;
1251
1252 if (!pdacl->num_aces) {
1253 if (!(pdacl_size - sizeof(struct smb_acl)) &&
1254 *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) {
1255 rc = -EACCES;
1256 goto err_out;
1257 }
1258 goto err_out;
1259 }
1260
1261 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
1262 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1263 DELETE;
1264
1265 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1266 aces_size = acl_size - sizeof(struct smb_acl);
1267 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1268 if (offsetof(struct smb_ace, access_req) > aces_size)
1269 break;
1270 ace_size = le16_to_cpu(ace->size);
1271 if (ace_size > aces_size)
1272 break;
1273 aces_size -= ace_size;
1274 granted |= le32_to_cpu(ace->access_req);
1275 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1276 }
1277
1278 if (!pdacl->num_aces)
1279 granted = GENERIC_ALL_FLAGS;
1280 }
1281
1282 if (!uid)
1283 sid_type = SIDUNIX_USER;
1284 id_to_sid(uid, sid_type, &sid);
1285
1286 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1287 aces_size = acl_size - sizeof(struct smb_acl);
1288 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1289 if (offsetof(struct smb_ace, access_req) > aces_size)
1290 break;
1291 ace_size = le16_to_cpu(ace->size);
1292 if (ace_size > aces_size)
1293 break;
1294 aces_size -= ace_size;
1295
1296 if (!compare_sids(&sid, &ace->sid) ||
1297 !compare_sids(&sid_unix_NFS_mode, &ace->sid)) {
1298 found = 1;
1299 break;
1300 }
1301 if (!compare_sids(&sid_everyone, &ace->sid))
1302 others_ace = ace;
1303
1304 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1305 }
1306
1307 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
1308 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1309 DELETE;
1310
1311 granted |= le32_to_cpu(ace->access_req);
1312
1313 if (!pdacl->num_aces)
1314 granted = GENERIC_ALL_FLAGS;
1315 }
1316
1317 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
1318 posix_acls = get_inode_acl(d_inode(path->dentry), ACL_TYPE_ACCESS);
1319 if (!IS_ERR_OR_NULL(posix_acls) && !found) {
1320 unsigned int id = -1;
1321
1322 pa_entry = posix_acls->a_entries;
1323 for (i = 0; i < posix_acls->a_count; i++, pa_entry++) {
1324 if (pa_entry->e_tag == ACL_USER)
1325 id = posix_acl_uid_translate(idmap, pa_entry);
1326 else if (pa_entry->e_tag == ACL_GROUP)
1327 id = posix_acl_gid_translate(idmap, pa_entry);
1328 else
1329 continue;
1330
1331 if (id == uid) {
1332 mode_to_access_flags(pa_entry->e_perm,
1333 0777,
1334 &access_bits);
1335 if (!access_bits)
1336 access_bits =
1337 SET_MINIMUM_RIGHTS;
1338 posix_acl_release(posix_acls);
1339 goto check_access_bits;
1340 }
1341 }
1342 }
1343 if (!IS_ERR_OR_NULL(posix_acls))
1344 posix_acl_release(posix_acls);
1345 }
1346
1347 if (!found) {
1348 if (others_ace) {
1349 ace = others_ace;
1350 } else {
1351 ksmbd_debug(SMB, "Can't find corresponding sid\n");
1352 rc = -EACCES;
1353 goto err_out;
1354 }
1355 }
1356
1357 switch (ace->type) {
1358 case ACCESS_ALLOWED_ACE_TYPE:
1359 access_bits = le32_to_cpu(ace->access_req);
1360 break;
1361 case ACCESS_DENIED_ACE_TYPE:
1362 case ACCESS_DENIED_CALLBACK_ACE_TYPE:
1363 access_bits = le32_to_cpu(~ace->access_req);
1364 break;
1365 }
1366
1367 check_access_bits:
1368 if (granted &
1369 ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) {
1370 ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n",
1371 granted, le32_to_cpu(ace->access_req));
1372 rc = -EACCES;
1373 goto err_out;
1374 }
1375
1376 *pdaccess = cpu_to_le32(granted);
1377 err_out:
1378 kfree(pntsd);
1379 return rc;
1380 }
1381
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)1382 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
1383 const struct path *path, struct smb_ntsd *pntsd, int ntsd_len,
1384 bool type_check, bool get_write)
1385 {
1386 int rc;
1387 struct smb_fattr fattr = {{0}};
1388 struct inode *inode = d_inode(path->dentry);
1389 struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1390 struct iattr newattrs;
1391
1392 fattr.cf_uid = INVALID_UID;
1393 fattr.cf_gid = INVALID_GID;
1394 fattr.cf_mode = inode->i_mode;
1395
1396 rc = parse_sec_desc(idmap, pntsd, ntsd_len, &fattr);
1397 if (rc)
1398 goto out;
1399
1400 newattrs.ia_valid = ATTR_CTIME;
1401 if (!uid_eq(fattr.cf_uid, INVALID_UID)) {
1402 newattrs.ia_valid |= ATTR_UID;
1403 newattrs.ia_uid = fattr.cf_uid;
1404 }
1405 if (!gid_eq(fattr.cf_gid, INVALID_GID)) {
1406 newattrs.ia_valid |= ATTR_GID;
1407 newattrs.ia_gid = fattr.cf_gid;
1408 }
1409 newattrs.ia_valid |= ATTR_MODE;
1410 newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
1411
1412 ksmbd_vfs_remove_acl_xattrs(idmap, path);
1413 /* Update posix acls */
1414 if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) {
1415 rc = set_posix_acl(idmap, path->dentry,
1416 ACL_TYPE_ACCESS, fattr.cf_acls);
1417 if (rc < 0)
1418 ksmbd_debug(SMB,
1419 "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
1420 rc);
1421 if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) {
1422 rc = set_posix_acl(idmap, path->dentry,
1423 ACL_TYPE_DEFAULT, fattr.cf_dacls);
1424 if (rc)
1425 ksmbd_debug(SMB,
1426 "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n",
1427 rc);
1428 }
1429 }
1430
1431 inode_lock(inode);
1432 rc = notify_change(idmap, path->dentry, &newattrs, NULL);
1433 inode_unlock(inode);
1434 if (rc)
1435 goto out;
1436
1437 /* Check it only calling from SD BUFFER context */
1438 if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT))
1439 goto out;
1440
1441 if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) {
1442 /* Update WinACL in xattr */
1443 ksmbd_vfs_remove_sd_xattrs(idmap, path);
1444 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, ntsd_len,
1445 get_write);
1446 }
1447
1448 out:
1449 posix_acl_release(fattr.cf_acls);
1450 posix_acl_release(fattr.cf_dacls);
1451 return rc;
1452 }
1453
ksmbd_init_domain(u32 * sub_auth)1454 void ksmbd_init_domain(u32 *sub_auth)
1455 {
1456 int i;
1457
1458 memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid));
1459 for (i = 0; i < 3; ++i)
1460 server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]);
1461 }
1462