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 = num_sat < num_saw ? 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 user_namespace * user_ns,struct smb_sid * psid,uint sidtype,struct smb_fattr * fattr)257 static int sid_to_id(struct user_namespace *user_ns,
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(user_ns, &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(user_ns, &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 user_namespace * user_ns,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 user_namespace *user_ns,
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 ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL);
405 if (!ppace)
406 return;
407
408 ret = init_acl_state(&acl_state, num_aces);
409 if (ret)
410 return;
411 ret = init_acl_state(&default_acl_state, num_aces);
412 if (ret) {
413 free_acl_state(&acl_state);
414 return;
415 }
416
417 /*
418 * reset rwx permissions for user/group/other.
419 * Also, if num_aces is 0 i.e. DACL has no ACEs,
420 * user/group/other have no permissions
421 */
422 for (i = 0; i < num_aces; ++i) {
423 if (end_of_acl - acl_base < acl_size)
424 break;
425
426 ppace[i] = (struct smb_ace *)(acl_base + acl_size);
427 acl_base = (char *)ppace[i];
428 acl_size = offsetof(struct smb_ace, sid) +
429 offsetof(struct smb_sid, sub_auth);
430
431 if (end_of_acl - acl_base < acl_size ||
432 ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES ||
433 (end_of_acl - acl_base <
434 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) ||
435 (le16_to_cpu(ppace[i]->size) <
436 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth))
437 break;
438
439 acl_size = le16_to_cpu(ppace[i]->size);
440 ppace[i]->access_req =
441 smb_map_generic_desired_access(ppace[i]->access_req);
442
443 if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) {
444 fattr->cf_mode =
445 le32_to_cpu(ppace[i]->sid.sub_auth[2]);
446 break;
447 } else if (!compare_sids(&ppace[i]->sid, pownersid)) {
448 acl_mode = access_flags_to_mode(fattr,
449 ppace[i]->access_req,
450 ppace[i]->type);
451 acl_mode &= 0700;
452
453 if (!owner_found) {
454 mode &= ~(0700);
455 mode |= acl_mode;
456 }
457 owner_found = true;
458 } else if (!compare_sids(&ppace[i]->sid, pgrpsid) ||
459 ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] ==
460 DOMAIN_USER_RID_LE) {
461 acl_mode = access_flags_to_mode(fattr,
462 ppace[i]->access_req,
463 ppace[i]->type);
464 acl_mode &= 0070;
465 if (!group_found) {
466 mode &= ~(0070);
467 mode |= acl_mode;
468 }
469 group_found = true;
470 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) {
471 acl_mode = access_flags_to_mode(fattr,
472 ppace[i]->access_req,
473 ppace[i]->type);
474 acl_mode &= 0007;
475 if (!others_found) {
476 mode &= ~(0007);
477 mode |= acl_mode;
478 }
479 others_found = true;
480 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) {
481 continue;
482 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) {
483 continue;
484 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) {
485 continue;
486 } else {
487 struct smb_fattr temp_fattr;
488
489 acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
490 ppace[i]->type);
491 temp_fattr.cf_uid = INVALID_UID;
492 ret = sid_to_id(user_ns, &ppace[i]->sid, SIDOWNER, &temp_fattr);
493 if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) {
494 pr_err("%s: Error %d mapping Owner SID to uid\n",
495 __func__, ret);
496 continue;
497 }
498
499 acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
500 acl_state.users->aces[acl_state.users->n].uid =
501 temp_fattr.cf_uid;
502 acl_state.users->aces[acl_state.users->n++].perms.allow =
503 ((acl_mode & 0700) >> 6) | 0004;
504 default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
505 default_acl_state.users->aces[default_acl_state.users->n].uid =
506 temp_fattr.cf_uid;
507 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
508 ((acl_mode & 0700) >> 6) | 0004;
509 }
510 }
511 kfree(ppace);
512
513 if (owner_found) {
514 /* The owner must be set to at least read-only. */
515 acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
516 acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid;
517 acl_state.users->aces[acl_state.users->n++].perms.allow =
518 ((mode & 0700) >> 6) | 0004;
519 default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
520 default_acl_state.users->aces[default_acl_state.users->n].uid =
521 fattr->cf_uid;
522 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
523 ((mode & 0700) >> 6) | 0004;
524 }
525
526 if (group_found) {
527 acl_state.group.allow = (mode & 0070) >> 3;
528 acl_state.groups->aces[acl_state.groups->n].gid =
529 fattr->cf_gid;
530 acl_state.groups->aces[acl_state.groups->n++].perms.allow =
531 (mode & 0070) >> 3;
532 default_acl_state.group.allow = (mode & 0070) >> 3;
533 default_acl_state.groups->aces[default_acl_state.groups->n].gid =
534 fattr->cf_gid;
535 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow =
536 (mode & 0070) >> 3;
537 }
538
539 if (others_found) {
540 fattr->cf_mode &= ~(0007);
541 fattr->cf_mode |= mode & 0007;
542
543 acl_state.other.allow = mode & 0007;
544 default_acl_state.other.allow = mode & 0007;
545 }
546
547 if (acl_state.users->n || acl_state.groups->n) {
548 acl_state.mask.allow = 0x07;
549
550 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
551 fattr->cf_acls =
552 posix_acl_alloc(acl_state.users->n +
553 acl_state.groups->n + 4, GFP_KERNEL);
554 if (fattr->cf_acls) {
555 cf_pace = fattr->cf_acls->a_entries;
556 posix_state_to_acl(&acl_state, cf_pace);
557 }
558 }
559 }
560
561 if (default_acl_state.users->n || default_acl_state.groups->n) {
562 default_acl_state.mask.allow = 0x07;
563
564 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
565 fattr->cf_dacls =
566 posix_acl_alloc(default_acl_state.users->n +
567 default_acl_state.groups->n + 4, GFP_KERNEL);
568 if (fattr->cf_dacls) {
569 cf_pdace = fattr->cf_dacls->a_entries;
570 posix_state_to_acl(&default_acl_state, cf_pdace);
571 }
572 }
573 }
574 free_acl_state(&acl_state);
575 free_acl_state(&default_acl_state);
576 }
577
set_posix_acl_entries_dacl(struct user_namespace * user_ns,struct smb_ace * pndace,struct smb_fattr * fattr,u32 * num_aces,u16 * size,u32 nt_aces_num)578 static void set_posix_acl_entries_dacl(struct user_namespace *user_ns,
579 struct smb_ace *pndace,
580 struct smb_fattr *fattr, u32 *num_aces,
581 u16 *size, u32 nt_aces_num)
582 {
583 struct posix_acl_entry *pace;
584 struct smb_sid *sid;
585 struct smb_ace *ntace;
586 int i, j;
587
588 if (!fattr->cf_acls)
589 goto posix_default_acl;
590
591 pace = fattr->cf_acls->a_entries;
592 for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) {
593 int flags = 0;
594
595 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
596 if (!sid)
597 break;
598
599 if (pace->e_tag == ACL_USER) {
600 uid_t uid;
601 unsigned int sid_type = SIDOWNER;
602
603 uid = posix_acl_uid_translate(user_ns, pace);
604 if (!uid)
605 sid_type = SIDUNIX_USER;
606 id_to_sid(uid, sid_type, sid);
607 } else if (pace->e_tag == ACL_GROUP) {
608 gid_t gid;
609
610 gid = posix_acl_gid_translate(user_ns, pace);
611 id_to_sid(gid, SIDUNIX_GROUP, sid);
612 } else if (pace->e_tag == ACL_OTHER && !nt_aces_num) {
613 smb_copy_sid(sid, &sid_everyone);
614 } else {
615 kfree(sid);
616 continue;
617 }
618 ntace = pndace;
619 for (j = 0; j < nt_aces_num; j++) {
620 if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] ==
621 sid->sub_auth[sid->num_subauth - 1])
622 goto pass_same_sid;
623 ntace = (struct smb_ace *)((char *)ntace +
624 le16_to_cpu(ntace->size));
625 }
626
627 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER)
628 flags = 0x03;
629
630 ntace = (struct smb_ace *)((char *)pndace + *size);
631 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags,
632 pace->e_perm, 0777);
633 (*num_aces)++;
634 if (pace->e_tag == ACL_USER)
635 ntace->access_req |=
636 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
637
638 if (S_ISDIR(fattr->cf_mode) &&
639 (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) {
640 ntace = (struct smb_ace *)((char *)pndace + *size);
641 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED,
642 0x03, pace->e_perm, 0777);
643 (*num_aces)++;
644 if (pace->e_tag == ACL_USER)
645 ntace->access_req |=
646 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
647 }
648
649 pass_same_sid:
650 kfree(sid);
651 }
652
653 if (nt_aces_num)
654 return;
655
656 posix_default_acl:
657 if (!fattr->cf_dacls)
658 return;
659
660 pace = fattr->cf_dacls->a_entries;
661 for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) {
662 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
663 if (!sid)
664 break;
665
666 if (pace->e_tag == ACL_USER) {
667 uid_t uid;
668
669 uid = posix_acl_uid_translate(user_ns, pace);
670 id_to_sid(uid, SIDCREATOR_OWNER, sid);
671 } else if (pace->e_tag == ACL_GROUP) {
672 gid_t gid;
673
674 gid = posix_acl_gid_translate(user_ns, pace);
675 id_to_sid(gid, SIDCREATOR_GROUP, sid);
676 } else {
677 kfree(sid);
678 continue;
679 }
680
681 ntace = (struct smb_ace *)((char *)pndace + *size);
682 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b,
683 pace->e_perm, 0777);
684 (*num_aces)++;
685 if (pace->e_tag == ACL_USER)
686 ntace->access_req |=
687 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
688 kfree(sid);
689 }
690 }
691
set_ntacl_dacl(struct user_namespace * user_ns,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)692 static void set_ntacl_dacl(struct user_namespace *user_ns,
693 struct smb_acl *pndacl,
694 struct smb_acl *nt_dacl,
695 unsigned int aces_size,
696 const struct smb_sid *pownersid,
697 const struct smb_sid *pgrpsid,
698 struct smb_fattr *fattr)
699 {
700 struct smb_ace *ntace, *pndace;
701 int nt_num_aces = le32_to_cpu(nt_dacl->num_aces), num_aces = 0;
702 unsigned short size = 0;
703 int i;
704
705 pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
706 if (nt_num_aces) {
707 ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl));
708 for (i = 0; i < nt_num_aces; i++) {
709 unsigned short nt_ace_size;
710
711 if (offsetof(struct smb_ace, access_req) > aces_size)
712 break;
713
714 nt_ace_size = le16_to_cpu(ntace->size);
715 if (nt_ace_size > aces_size)
716 break;
717
718 memcpy((char *)pndace + size, ntace, nt_ace_size);
719 size += nt_ace_size;
720 aces_size -= nt_ace_size;
721 ntace = (struct smb_ace *)((char *)ntace + nt_ace_size);
722 num_aces++;
723 }
724 }
725
726 set_posix_acl_entries_dacl(user_ns, pndace, fattr,
727 &num_aces, &size, nt_num_aces);
728 pndacl->num_aces = cpu_to_le32(num_aces);
729 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
730 }
731
set_mode_dacl(struct user_namespace * user_ns,struct smb_acl * pndacl,struct smb_fattr * fattr)732 static void set_mode_dacl(struct user_namespace *user_ns,
733 struct smb_acl *pndacl, struct smb_fattr *fattr)
734 {
735 struct smb_ace *pace, *pndace;
736 u32 num_aces = 0;
737 u16 size = 0, ace_size = 0;
738 uid_t uid;
739 const struct smb_sid *sid;
740
741 pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
742
743 if (fattr->cf_acls) {
744 set_posix_acl_entries_dacl(user_ns, pndace, fattr,
745 &num_aces, &size, num_aces);
746 goto out;
747 }
748
749 /* owner RID */
750 uid = from_kuid(&init_user_ns, fattr->cf_uid);
751 if (uid)
752 sid = &server_conf.domain_sid;
753 else
754 sid = &sid_unix_users;
755 ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0,
756 fattr->cf_mode, 0700);
757 pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid);
758 pace->size = cpu_to_le16(ace_size + 4);
759 size += le16_to_cpu(pace->size);
760 pace = (struct smb_ace *)((char *)pndace + size);
761
762 /* Group RID */
763 ace_size = fill_ace_for_sid(pace, &sid_unix_groups,
764 ACCESS_ALLOWED, 0, fattr->cf_mode, 0070);
765 pace->sid.sub_auth[pace->sid.num_subauth++] =
766 cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid));
767 pace->size = cpu_to_le16(ace_size + 4);
768 size += le16_to_cpu(pace->size);
769 pace = (struct smb_ace *)((char *)pndace + size);
770 num_aces = 3;
771
772 if (S_ISDIR(fattr->cf_mode)) {
773 pace = (struct smb_ace *)((char *)pndace + size);
774
775 /* creator owner */
776 size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED,
777 0x0b, fattr->cf_mode, 0700);
778 pace = (struct smb_ace *)((char *)pndace + size);
779
780 /* creator group */
781 size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED,
782 0x0b, fattr->cf_mode, 0070);
783 pace = (struct smb_ace *)((char *)pndace + size);
784 num_aces = 5;
785 }
786
787 /* other */
788 size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0,
789 fattr->cf_mode, 0007);
790
791 out:
792 pndacl->num_aces = cpu_to_le32(num_aces);
793 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
794 }
795
parse_sid(struct smb_sid * psid,char * end_of_acl)796 static int parse_sid(struct smb_sid *psid, char *end_of_acl)
797 {
798 /*
799 * validate that we do not go past end of ACL - sid must be at least 8
800 * bytes long (assuming no sub-auths - e.g. the null SID
801 */
802 if (end_of_acl < (char *)psid + 8) {
803 pr_err("ACL too small to parse SID %p\n", psid);
804 return -EINVAL;
805 }
806
807 return 0;
808 }
809
810 /* Convert CIFS ACL to POSIX form */
parse_sec_desc(struct user_namespace * user_ns,struct smb_ntsd * pntsd,int acl_len,struct smb_fattr * fattr)811 int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
812 int acl_len, struct smb_fattr *fattr)
813 {
814 int rc = 0;
815 struct smb_sid *owner_sid_ptr, *group_sid_ptr;
816 struct smb_acl *dacl_ptr; /* no need for SACL ptr */
817 char *end_of_acl = ((char *)pntsd) + acl_len;
818 __u32 dacloffset;
819 int pntsd_type;
820
821 if (!pntsd)
822 return -EIO;
823
824 if (acl_len < sizeof(struct smb_ntsd))
825 return -EINVAL;
826
827 owner_sid_ptr = (struct smb_sid *)((char *)pntsd +
828 le32_to_cpu(pntsd->osidoffset));
829 group_sid_ptr = (struct smb_sid *)((char *)pntsd +
830 le32_to_cpu(pntsd->gsidoffset));
831 dacloffset = le32_to_cpu(pntsd->dacloffset);
832 dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset);
833 ksmbd_debug(SMB,
834 "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n",
835 pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
836 le32_to_cpu(pntsd->gsidoffset),
837 le32_to_cpu(pntsd->sacloffset), dacloffset);
838
839 pntsd_type = le16_to_cpu(pntsd->type);
840 if (!(pntsd_type & DACL_PRESENT)) {
841 ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n");
842 return rc;
843 }
844
845 pntsd->type = cpu_to_le16(DACL_PRESENT);
846
847 if (pntsd->osidoffset) {
848 rc = parse_sid(owner_sid_ptr, end_of_acl);
849 if (rc) {
850 pr_err("%s: Error %d parsing Owner SID\n", __func__, rc);
851 return rc;
852 }
853
854 rc = sid_to_id(user_ns, owner_sid_ptr, SIDOWNER, fattr);
855 if (rc) {
856 pr_err("%s: Error %d mapping Owner SID to uid\n",
857 __func__, rc);
858 owner_sid_ptr = NULL;
859 }
860 }
861
862 if (pntsd->gsidoffset) {
863 rc = parse_sid(group_sid_ptr, end_of_acl);
864 if (rc) {
865 pr_err("%s: Error %d mapping Owner SID to gid\n",
866 __func__, rc);
867 return rc;
868 }
869 rc = sid_to_id(user_ns, group_sid_ptr, SIDUNIX_GROUP, fattr);
870 if (rc) {
871 pr_err("%s: Error %d mapping Group SID to gid\n",
872 __func__, rc);
873 group_sid_ptr = NULL;
874 }
875 }
876
877 if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) ==
878 (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ))
879 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
880 if (pntsd_type & DACL_PROTECTED)
881 pntsd->type |= cpu_to_le16(DACL_PROTECTED);
882
883 if (dacloffset) {
884 parse_dacl(user_ns, dacl_ptr, end_of_acl,
885 owner_sid_ptr, group_sid_ptr, fattr);
886 }
887
888 return 0;
889 }
890
891 /* Convert permission bits from mode to equivalent CIFS ACL */
build_sec_desc(struct user_namespace * user_ns,struct smb_ntsd * pntsd,struct smb_ntsd * ppntsd,int ppntsd_size,int addition_info,__u32 * secdesclen,struct smb_fattr * fattr)892 int build_sec_desc(struct user_namespace *user_ns,
893 struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
894 int ppntsd_size, int addition_info, __u32 *secdesclen,
895 struct smb_fattr *fattr)
896 {
897 int rc = 0;
898 __u32 offset;
899 struct smb_sid *owner_sid_ptr, *group_sid_ptr;
900 struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr;
901 struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */
902 uid_t uid;
903 gid_t gid;
904 unsigned int sid_type = SIDOWNER;
905
906 nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
907 if (!nowner_sid_ptr)
908 return -ENOMEM;
909
910 uid = from_kuid(&init_user_ns, fattr->cf_uid);
911 if (!uid)
912 sid_type = SIDUNIX_USER;
913 id_to_sid(uid, sid_type, nowner_sid_ptr);
914
915 ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
916 if (!ngroup_sid_ptr) {
917 kfree(nowner_sid_ptr);
918 return -ENOMEM;
919 }
920
921 gid = from_kgid(&init_user_ns, fattr->cf_gid);
922 id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr);
923
924 offset = sizeof(struct smb_ntsd);
925 pntsd->sacloffset = 0;
926 pntsd->revision = cpu_to_le16(1);
927 pntsd->type = cpu_to_le16(SELF_RELATIVE);
928 if (ppntsd)
929 pntsd->type |= ppntsd->type;
930
931 if (addition_info & OWNER_SECINFO) {
932 pntsd->osidoffset = cpu_to_le32(offset);
933 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
934 smb_copy_sid(owner_sid_ptr, nowner_sid_ptr);
935 offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4);
936 }
937
938 if (addition_info & GROUP_SECINFO) {
939 pntsd->gsidoffset = cpu_to_le32(offset);
940 group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
941 smb_copy_sid(group_sid_ptr, ngroup_sid_ptr);
942 offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4);
943 }
944
945 if (addition_info & DACL_SECINFO) {
946 pntsd->type |= cpu_to_le16(DACL_PRESENT);
947 dacl_ptr = (struct smb_acl *)((char *)pntsd + offset);
948 dacl_ptr->revision = cpu_to_le16(2);
949 dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl));
950 dacl_ptr->num_aces = 0;
951
952 if (!ppntsd) {
953 set_mode_dacl(user_ns, dacl_ptr, fattr);
954 } else {
955 struct smb_acl *ppdacl_ptr;
956 unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset);
957 int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset;
958
959 if (!dacl_offset ||
960 (dacl_offset + sizeof(struct smb_acl) > ppntsd_size))
961 goto out;
962
963 ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset);
964 ppdacl_size = le16_to_cpu(ppdacl_ptr->size);
965 if (ppdacl_size > ntacl_size ||
966 ppdacl_size < sizeof(struct smb_acl))
967 goto out;
968
969 set_ntacl_dacl(user_ns, dacl_ptr, ppdacl_ptr,
970 ntacl_size - sizeof(struct smb_acl),
971 nowner_sid_ptr, ngroup_sid_ptr,
972 fattr);
973 }
974 pntsd->dacloffset = cpu_to_le32(offset);
975 offset += le16_to_cpu(dacl_ptr->size);
976 }
977
978 out:
979 kfree(nowner_sid_ptr);
980 kfree(ngroup_sid_ptr);
981 *secdesclen = offset;
982 return rc;
983 }
984
smb_set_ace(struct smb_ace * ace,const struct smb_sid * sid,u8 type,u8 flags,__le32 access_req)985 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type,
986 u8 flags, __le32 access_req)
987 {
988 ace->type = type;
989 ace->flags = flags;
990 ace->access_req = access_req;
991 smb_copy_sid(&ace->sid, sid);
992 ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + (sid->num_subauth * 4));
993 }
994
smb_inherit_dacl(struct ksmbd_conn * conn,const struct path * path,unsigned int uid,unsigned int gid)995 int smb_inherit_dacl(struct ksmbd_conn *conn,
996 const struct path *path,
997 unsigned int uid, unsigned int gid)
998 {
999 const struct smb_sid *psid, *creator = NULL;
1000 struct smb_ace *parent_aces, *aces;
1001 struct smb_acl *parent_pdacl;
1002 struct smb_ntsd *parent_pntsd = NULL;
1003 struct smb_sid owner_sid, group_sid;
1004 struct dentry *parent = path->dentry->d_parent;
1005 struct user_namespace *user_ns = mnt_user_ns(path->mnt);
1006 int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size;
1007 int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size;
1008 char *aces_base;
1009 bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
1010
1011 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, user_ns,
1012 parent, &parent_pntsd);
1013 if (pntsd_size <= 0)
1014 return -ENOENT;
1015 dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
1016 if (!dacloffset || (dacloffset + sizeof(struct smb_acl) > pntsd_size)) {
1017 rc = -EINVAL;
1018 goto free_parent_pntsd;
1019 }
1020
1021 parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset);
1022 acl_len = pntsd_size - dacloffset;
1023 num_aces = le32_to_cpu(parent_pdacl->num_aces);
1024 pntsd_type = le16_to_cpu(parent_pntsd->type);
1025 pdacl_size = le16_to_cpu(parent_pdacl->size);
1026
1027 if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) {
1028 rc = -EINVAL;
1029 goto free_parent_pntsd;
1030 }
1031
1032 aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL);
1033 if (!aces_base) {
1034 rc = -ENOMEM;
1035 goto free_parent_pntsd;
1036 }
1037
1038 aces = (struct smb_ace *)aces_base;
1039 parent_aces = (struct smb_ace *)((char *)parent_pdacl +
1040 sizeof(struct smb_acl));
1041 aces_size = acl_len - sizeof(struct smb_acl);
1042
1043 if (pntsd_type & DACL_AUTO_INHERITED)
1044 inherited_flags = INHERITED_ACE;
1045
1046 for (i = 0; i < num_aces; i++) {
1047 int pace_size;
1048
1049 if (offsetof(struct smb_ace, access_req) > aces_size)
1050 break;
1051
1052 pace_size = le16_to_cpu(parent_aces->size);
1053 if (pace_size > aces_size)
1054 break;
1055
1056 aces_size -= pace_size;
1057
1058 flags = parent_aces->flags;
1059 if (!smb_inherit_flags(flags, is_dir))
1060 goto pass;
1061 if (is_dir) {
1062 flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE);
1063 if (!(flags & CONTAINER_INHERIT_ACE))
1064 flags |= INHERIT_ONLY_ACE;
1065 if (flags & NO_PROPAGATE_INHERIT_ACE)
1066 flags = 0;
1067 } else {
1068 flags = 0;
1069 }
1070
1071 if (!compare_sids(&creator_owner, &parent_aces->sid)) {
1072 creator = &creator_owner;
1073 id_to_sid(uid, SIDOWNER, &owner_sid);
1074 psid = &owner_sid;
1075 } else if (!compare_sids(&creator_group, &parent_aces->sid)) {
1076 creator = &creator_group;
1077 id_to_sid(gid, SIDUNIX_GROUP, &group_sid);
1078 psid = &group_sid;
1079 } else {
1080 creator = NULL;
1081 psid = &parent_aces->sid;
1082 }
1083
1084 if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) {
1085 smb_set_ace(aces, psid, parent_aces->type, inherited_flags,
1086 parent_aces->access_req);
1087 nt_size += le16_to_cpu(aces->size);
1088 ace_cnt++;
1089 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1090 flags |= INHERIT_ONLY_ACE;
1091 psid = creator;
1092 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) {
1093 psid = &parent_aces->sid;
1094 }
1095
1096 smb_set_ace(aces, psid, parent_aces->type, flags | inherited_flags,
1097 parent_aces->access_req);
1098 nt_size += le16_to_cpu(aces->size);
1099 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1100 ace_cnt++;
1101 pass:
1102 parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size);
1103 }
1104
1105 if (nt_size > 0) {
1106 struct smb_ntsd *pntsd;
1107 struct smb_acl *pdacl;
1108 struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL;
1109 int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size;
1110
1111 if (parent_pntsd->osidoffset) {
1112 powner_sid = (struct smb_sid *)((char *)parent_pntsd +
1113 le32_to_cpu(parent_pntsd->osidoffset));
1114 powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4);
1115 }
1116 if (parent_pntsd->gsidoffset) {
1117 pgroup_sid = (struct smb_sid *)((char *)parent_pntsd +
1118 le32_to_cpu(parent_pntsd->gsidoffset));
1119 pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4);
1120 }
1121
1122 pntsd = kzalloc(sizeof(struct smb_ntsd) + powner_sid_size +
1123 pgroup_sid_size + sizeof(struct smb_acl) +
1124 nt_size, GFP_KERNEL);
1125 if (!pntsd) {
1126 rc = -ENOMEM;
1127 goto free_aces_base;
1128 }
1129
1130 pntsd->revision = cpu_to_le16(1);
1131 pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT);
1132 if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED)
1133 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
1134 pntsd_size = sizeof(struct smb_ntsd);
1135 pntsd->osidoffset = parent_pntsd->osidoffset;
1136 pntsd->gsidoffset = parent_pntsd->gsidoffset;
1137 pntsd->dacloffset = parent_pntsd->dacloffset;
1138
1139 if (pntsd->osidoffset) {
1140 struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd +
1141 le32_to_cpu(pntsd->osidoffset));
1142 memcpy(owner_sid, powner_sid, powner_sid_size);
1143 pntsd_size += powner_sid_size;
1144 }
1145
1146 if (pntsd->gsidoffset) {
1147 struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd +
1148 le32_to_cpu(pntsd->gsidoffset));
1149 memcpy(group_sid, pgroup_sid, pgroup_sid_size);
1150 pntsd_size += pgroup_sid_size;
1151 }
1152
1153 if (pntsd->dacloffset) {
1154 struct smb_ace *pace;
1155
1156 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1157 pdacl->revision = cpu_to_le16(2);
1158 pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size);
1159 pdacl->num_aces = cpu_to_le32(ace_cnt);
1160 pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1161 memcpy(pace, aces_base, nt_size);
1162 pntsd_size += sizeof(struct smb_acl) + nt_size;
1163 }
1164
1165 ksmbd_vfs_set_sd_xattr(conn, user_ns,
1166 path->dentry, pntsd, pntsd_size);
1167 kfree(pntsd);
1168 }
1169
1170 free_aces_base:
1171 kfree(aces_base);
1172 free_parent_pntsd:
1173 kfree(parent_pntsd);
1174 return rc;
1175 }
1176
smb_inherit_flags(int flags,bool is_dir)1177 bool smb_inherit_flags(int flags, bool is_dir)
1178 {
1179 if (!is_dir)
1180 return (flags & OBJECT_INHERIT_ACE) != 0;
1181
1182 if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE))
1183 return true;
1184
1185 if (flags & CONTAINER_INHERIT_ACE)
1186 return true;
1187 return false;
1188 }
1189
smb_check_perm_dacl(struct ksmbd_conn * conn,const struct path * path,__le32 * pdaccess,int uid)1190 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
1191 __le32 *pdaccess, int uid)
1192 {
1193 struct user_namespace *user_ns = mnt_user_ns(path->mnt);
1194 struct smb_ntsd *pntsd = NULL;
1195 struct smb_acl *pdacl;
1196 struct posix_acl *posix_acls;
1197 int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size, dacl_offset;
1198 struct smb_sid sid;
1199 int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
1200 struct smb_ace *ace;
1201 int i, found = 0;
1202 unsigned int access_bits = 0;
1203 struct smb_ace *others_ace = NULL;
1204 struct posix_acl_entry *pa_entry;
1205 unsigned int sid_type = SIDOWNER;
1206 unsigned short ace_size;
1207
1208 ksmbd_debug(SMB, "check permission using windows acl\n");
1209 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, user_ns,
1210 path->dentry, &pntsd);
1211 if (pntsd_size <= 0 || !pntsd)
1212 goto err_out;
1213
1214 dacl_offset = le32_to_cpu(pntsd->dacloffset);
1215 if (!dacl_offset ||
1216 (dacl_offset + sizeof(struct smb_acl) > pntsd_size))
1217 goto err_out;
1218
1219 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1220 acl_size = pntsd_size - dacl_offset;
1221 pdacl_size = le16_to_cpu(pdacl->size);
1222
1223 if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl))
1224 goto err_out;
1225
1226 if (!pdacl->num_aces) {
1227 if (!(pdacl_size - sizeof(struct smb_acl)) &&
1228 *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) {
1229 rc = -EACCES;
1230 goto err_out;
1231 }
1232 goto err_out;
1233 }
1234
1235 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
1236 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1237 DELETE;
1238
1239 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1240 aces_size = acl_size - sizeof(struct smb_acl);
1241 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1242 if (offsetof(struct smb_ace, access_req) > aces_size)
1243 break;
1244 ace_size = le16_to_cpu(ace->size);
1245 if (ace_size > aces_size)
1246 break;
1247 aces_size -= ace_size;
1248 granted |= le32_to_cpu(ace->access_req);
1249 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1250 }
1251
1252 if (!pdacl->num_aces)
1253 granted = GENERIC_ALL_FLAGS;
1254 }
1255
1256 if (!uid)
1257 sid_type = SIDUNIX_USER;
1258 id_to_sid(uid, sid_type, &sid);
1259
1260 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1261 aces_size = acl_size - sizeof(struct smb_acl);
1262 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1263 if (offsetof(struct smb_ace, access_req) > aces_size)
1264 break;
1265 ace_size = le16_to_cpu(ace->size);
1266 if (ace_size > aces_size)
1267 break;
1268 aces_size -= ace_size;
1269
1270 if (!compare_sids(&sid, &ace->sid) ||
1271 !compare_sids(&sid_unix_NFS_mode, &ace->sid)) {
1272 found = 1;
1273 break;
1274 }
1275 if (!compare_sids(&sid_everyone, &ace->sid))
1276 others_ace = ace;
1277
1278 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1279 }
1280
1281 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
1282 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1283 DELETE;
1284
1285 granted |= le32_to_cpu(ace->access_req);
1286
1287 if (!pdacl->num_aces)
1288 granted = GENERIC_ALL_FLAGS;
1289 }
1290
1291 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
1292 posix_acls = get_acl(d_inode(path->dentry), ACL_TYPE_ACCESS);
1293 if (posix_acls && !found) {
1294 unsigned int id = -1;
1295
1296 pa_entry = posix_acls->a_entries;
1297 for (i = 0; i < posix_acls->a_count; i++, pa_entry++) {
1298 if (pa_entry->e_tag == ACL_USER)
1299 id = posix_acl_uid_translate(user_ns, pa_entry);
1300 else if (pa_entry->e_tag == ACL_GROUP)
1301 id = posix_acl_gid_translate(user_ns, pa_entry);
1302 else
1303 continue;
1304
1305 if (id == uid) {
1306 mode_to_access_flags(pa_entry->e_perm,
1307 0777,
1308 &access_bits);
1309 if (!access_bits)
1310 access_bits =
1311 SET_MINIMUM_RIGHTS;
1312 posix_acl_release(posix_acls);
1313 goto check_access_bits;
1314 }
1315 }
1316 }
1317 if (posix_acls)
1318 posix_acl_release(posix_acls);
1319 }
1320
1321 if (!found) {
1322 if (others_ace) {
1323 ace = others_ace;
1324 } else {
1325 ksmbd_debug(SMB, "Can't find corresponding sid\n");
1326 rc = -EACCES;
1327 goto err_out;
1328 }
1329 }
1330
1331 switch (ace->type) {
1332 case ACCESS_ALLOWED_ACE_TYPE:
1333 access_bits = le32_to_cpu(ace->access_req);
1334 break;
1335 case ACCESS_DENIED_ACE_TYPE:
1336 case ACCESS_DENIED_CALLBACK_ACE_TYPE:
1337 access_bits = le32_to_cpu(~ace->access_req);
1338 break;
1339 }
1340
1341 check_access_bits:
1342 if (granted &
1343 ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) {
1344 ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n",
1345 granted, le32_to_cpu(ace->access_req));
1346 rc = -EACCES;
1347 goto err_out;
1348 }
1349
1350 *pdaccess = cpu_to_le32(granted);
1351 err_out:
1352 kfree(pntsd);
1353 return rc;
1354 }
1355
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)1356 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
1357 const struct path *path, struct smb_ntsd *pntsd, int ntsd_len,
1358 bool type_check)
1359 {
1360 int rc;
1361 struct smb_fattr fattr = {{0}};
1362 struct inode *inode = d_inode(path->dentry);
1363 struct user_namespace *user_ns = mnt_user_ns(path->mnt);
1364 struct iattr newattrs;
1365
1366 fattr.cf_uid = INVALID_UID;
1367 fattr.cf_gid = INVALID_GID;
1368 fattr.cf_mode = inode->i_mode;
1369
1370 rc = parse_sec_desc(user_ns, pntsd, ntsd_len, &fattr);
1371 if (rc)
1372 goto out;
1373
1374 newattrs.ia_valid = ATTR_CTIME;
1375 if (!uid_eq(fattr.cf_uid, INVALID_UID)) {
1376 newattrs.ia_valid |= ATTR_UID;
1377 newattrs.ia_uid = fattr.cf_uid;
1378 }
1379 if (!gid_eq(fattr.cf_gid, INVALID_GID)) {
1380 newattrs.ia_valid |= ATTR_GID;
1381 newattrs.ia_gid = fattr.cf_gid;
1382 }
1383 newattrs.ia_valid |= ATTR_MODE;
1384 newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
1385
1386 ksmbd_vfs_remove_acl_xattrs(user_ns, path->dentry);
1387 /* Update posix acls */
1388 if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) {
1389 rc = set_posix_acl(user_ns, inode,
1390 ACL_TYPE_ACCESS, fattr.cf_acls);
1391 if (rc < 0)
1392 ksmbd_debug(SMB,
1393 "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
1394 rc);
1395 if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) {
1396 rc = set_posix_acl(user_ns, inode,
1397 ACL_TYPE_DEFAULT, fattr.cf_dacls);
1398 if (rc)
1399 ksmbd_debug(SMB,
1400 "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n",
1401 rc);
1402 }
1403 }
1404
1405 inode_lock(inode);
1406 rc = notify_change(user_ns, path->dentry, &newattrs, NULL);
1407 inode_unlock(inode);
1408 if (rc)
1409 goto out;
1410
1411 /* Check it only calling from SD BUFFER context */
1412 if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT))
1413 goto out;
1414
1415 if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) {
1416 /* Update WinACL in xattr */
1417 ksmbd_vfs_remove_sd_xattrs(user_ns, path->dentry);
1418 ksmbd_vfs_set_sd_xattr(conn, user_ns,
1419 path->dentry, pntsd, ntsd_len);
1420 }
1421
1422 out:
1423 posix_acl_release(fattr.cf_acls);
1424 posix_acl_release(fattr.cf_dacls);
1425 mark_inode_dirty(inode);
1426 return rc;
1427 }
1428
ksmbd_init_domain(u32 * sub_auth)1429 void ksmbd_init_domain(u32 *sub_auth)
1430 {
1431 int i;
1432
1433 memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid));
1434 for (i = 0; i < 3; ++i)
1435 server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]);
1436 }
1437