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 (psid->num_subauth == 0) {
274 pr_err("%s: zero subauthorities!\n", __func__);
275 return -EIO;
276 }
277
278 if (sidtype == SIDOWNER) {
279 kuid_t uid;
280 uid_t id;
281
282 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
283 uid = KUIDT_INIT(id);
284 uid = from_vfsuid(idmap, &init_user_ns, VFSUIDT_INIT(uid));
285 if (uid_valid(uid)) {
286 fattr->cf_uid = uid;
287 rc = 0;
288 }
289 } else {
290 kgid_t gid;
291 gid_t id;
292
293 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
294 gid = KGIDT_INIT(id);
295 gid = from_vfsgid(idmap, &init_user_ns, VFSGIDT_INIT(gid));
296 if (gid_valid(gid)) {
297 fattr->cf_gid = gid;
298 rc = 0;
299 }
300 }
301
302 return rc;
303 }
304
posix_state_to_acl(struct posix_acl_state * state,struct posix_acl_entry * pace)305 void posix_state_to_acl(struct posix_acl_state *state,
306 struct posix_acl_entry *pace)
307 {
308 int i;
309
310 pace->e_tag = ACL_USER_OBJ;
311 pace->e_perm = state->owner.allow;
312 for (i = 0; i < state->users->n; i++) {
313 pace++;
314 pace->e_tag = ACL_USER;
315 pace->e_uid = state->users->aces[i].uid;
316 pace->e_perm = state->users->aces[i].perms.allow;
317 }
318
319 pace++;
320 pace->e_tag = ACL_GROUP_OBJ;
321 pace->e_perm = state->group.allow;
322
323 for (i = 0; i < state->groups->n; i++) {
324 pace++;
325 pace->e_tag = ACL_GROUP;
326 pace->e_gid = state->groups->aces[i].gid;
327 pace->e_perm = state->groups->aces[i].perms.allow;
328 }
329
330 if (state->users->n || state->groups->n) {
331 pace++;
332 pace->e_tag = ACL_MASK;
333 pace->e_perm = state->mask.allow;
334 }
335
336 pace++;
337 pace->e_tag = ACL_OTHER;
338 pace->e_perm = state->other.allow;
339 }
340
init_acl_state(struct posix_acl_state * state,int cnt)341 int init_acl_state(struct posix_acl_state *state, int cnt)
342 {
343 int alloc;
344
345 memset(state, 0, sizeof(struct posix_acl_state));
346 /*
347 * In the worst case, each individual acl could be for a distinct
348 * named user or group, but we don't know which, so we allocate
349 * enough space for either:
350 */
351 alloc = sizeof(struct posix_ace_state_array)
352 + cnt * sizeof(struct posix_user_ace_state);
353 state->users = kzalloc(alloc, GFP_KERNEL);
354 if (!state->users)
355 return -ENOMEM;
356 state->groups = kzalloc(alloc, GFP_KERNEL);
357 if (!state->groups) {
358 kfree(state->users);
359 return -ENOMEM;
360 }
361 return 0;
362 }
363
free_acl_state(struct posix_acl_state * state)364 void free_acl_state(struct posix_acl_state *state)
365 {
366 kfree(state->users);
367 kfree(state->groups);
368 }
369
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)370 static void parse_dacl(struct mnt_idmap *idmap,
371 struct smb_acl *pdacl, char *end_of_acl,
372 struct smb_sid *pownersid, struct smb_sid *pgrpsid,
373 struct smb_fattr *fattr)
374 {
375 int i, ret;
376 int num_aces = 0;
377 unsigned int acl_size;
378 char *acl_base;
379 struct smb_ace **ppace;
380 struct posix_acl_entry *cf_pace, *cf_pdace;
381 struct posix_acl_state acl_state, default_acl_state;
382 umode_t mode = 0, acl_mode;
383 bool owner_found = false, group_found = false, others_found = false;
384
385 if (!pdacl)
386 return;
387
388 /* validate that we do not go past end of acl */
389 if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) ||
390 end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) {
391 pr_err("ACL too small to parse DACL\n");
392 return;
393 }
394
395 ksmbd_debug(SMB, "DACL revision %d size %d num aces %d\n",
396 le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size),
397 le32_to_cpu(pdacl->num_aces));
398
399 acl_base = (char *)pdacl;
400 acl_size = sizeof(struct smb_acl);
401
402 num_aces = le32_to_cpu(pdacl->num_aces);
403 if (num_aces <= 0)
404 return;
405
406 if (num_aces > (le16_to_cpu(pdacl->size) - sizeof(struct smb_acl)) /
407 (offsetof(struct smb_ace, sid) +
408 offsetof(struct smb_sid, sub_auth) + sizeof(__le16)))
409 return;
410
411 ret = init_acl_state(&acl_state, num_aces);
412 if (ret)
413 return;
414 ret = init_acl_state(&default_acl_state, num_aces);
415 if (ret) {
416 free_acl_state(&acl_state);
417 return;
418 }
419
420 ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL);
421 if (!ppace) {
422 free_acl_state(&default_acl_state);
423 free_acl_state(&acl_state);
424 return;
425 }
426
427 /*
428 * reset rwx permissions for user/group/other.
429 * Also, if num_aces is 0 i.e. DACL has no ACEs,
430 * user/group/other have no permissions
431 */
432 for (i = 0; i < num_aces; ++i) {
433 if (end_of_acl - acl_base < acl_size)
434 break;
435
436 ppace[i] = (struct smb_ace *)(acl_base + acl_size);
437 acl_base = (char *)ppace[i];
438 acl_size = offsetof(struct smb_ace, sid) +
439 offsetof(struct smb_sid, sub_auth);
440
441 if (end_of_acl - acl_base < acl_size ||
442 ppace[i]->sid.num_subauth == 0 ||
443 ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES ||
444 (end_of_acl - acl_base <
445 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) ||
446 (le16_to_cpu(ppace[i]->size) <
447 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth))
448 break;
449
450 acl_size = le16_to_cpu(ppace[i]->size);
451 ppace[i]->access_req =
452 smb_map_generic_desired_access(ppace[i]->access_req);
453
454 if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) {
455 fattr->cf_mode =
456 le32_to_cpu(ppace[i]->sid.sub_auth[2]);
457 break;
458 } else if (!compare_sids(&ppace[i]->sid, pownersid)) {
459 acl_mode = access_flags_to_mode(fattr,
460 ppace[i]->access_req,
461 ppace[i]->type);
462 acl_mode &= 0700;
463
464 if (!owner_found) {
465 mode &= ~(0700);
466 mode |= acl_mode;
467 }
468 owner_found = true;
469 } else if (!compare_sids(&ppace[i]->sid, pgrpsid) ||
470 ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] ==
471 DOMAIN_USER_RID_LE) {
472 acl_mode = access_flags_to_mode(fattr,
473 ppace[i]->access_req,
474 ppace[i]->type);
475 acl_mode &= 0070;
476 if (!group_found) {
477 mode &= ~(0070);
478 mode |= acl_mode;
479 }
480 group_found = true;
481 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) {
482 acl_mode = access_flags_to_mode(fattr,
483 ppace[i]->access_req,
484 ppace[i]->type);
485 acl_mode &= 0007;
486 if (!others_found) {
487 mode &= ~(0007);
488 mode |= acl_mode;
489 }
490 others_found = true;
491 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) {
492 continue;
493 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) {
494 continue;
495 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) {
496 continue;
497 } else {
498 struct smb_fattr temp_fattr;
499
500 acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
501 ppace[i]->type);
502 temp_fattr.cf_uid = INVALID_UID;
503 ret = sid_to_id(idmap, &ppace[i]->sid, SIDOWNER, &temp_fattr);
504 if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) {
505 pr_err("%s: Error %d mapping Owner SID to uid\n",
506 __func__, ret);
507 continue;
508 }
509
510 acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
511 acl_state.users->aces[acl_state.users->n].uid =
512 temp_fattr.cf_uid;
513 acl_state.users->aces[acl_state.users->n++].perms.allow =
514 ((acl_mode & 0700) >> 6) | 0004;
515 default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
516 default_acl_state.users->aces[default_acl_state.users->n].uid =
517 temp_fattr.cf_uid;
518 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
519 ((acl_mode & 0700) >> 6) | 0004;
520 }
521 }
522 kfree(ppace);
523
524 if (owner_found) {
525 /* The owner must be set to at least read-only. */
526 acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
527 acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid;
528 acl_state.users->aces[acl_state.users->n++].perms.allow =
529 ((mode & 0700) >> 6) | 0004;
530 default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
531 default_acl_state.users->aces[default_acl_state.users->n].uid =
532 fattr->cf_uid;
533 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
534 ((mode & 0700) >> 6) | 0004;
535 }
536
537 if (group_found) {
538 acl_state.group.allow = (mode & 0070) >> 3;
539 acl_state.groups->aces[acl_state.groups->n].gid =
540 fattr->cf_gid;
541 acl_state.groups->aces[acl_state.groups->n++].perms.allow =
542 (mode & 0070) >> 3;
543 default_acl_state.group.allow = (mode & 0070) >> 3;
544 default_acl_state.groups->aces[default_acl_state.groups->n].gid =
545 fattr->cf_gid;
546 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow =
547 (mode & 0070) >> 3;
548 }
549
550 if (others_found) {
551 fattr->cf_mode &= ~(0007);
552 fattr->cf_mode |= mode & 0007;
553
554 acl_state.other.allow = mode & 0007;
555 default_acl_state.other.allow = mode & 0007;
556 }
557
558 if (acl_state.users->n || acl_state.groups->n) {
559 acl_state.mask.allow = 0x07;
560
561 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
562 fattr->cf_acls =
563 posix_acl_alloc(acl_state.users->n +
564 acl_state.groups->n + 4, GFP_KERNEL);
565 if (fattr->cf_acls) {
566 cf_pace = fattr->cf_acls->a_entries;
567 posix_state_to_acl(&acl_state, cf_pace);
568 }
569 }
570 }
571
572 if (default_acl_state.users->n || default_acl_state.groups->n) {
573 default_acl_state.mask.allow = 0x07;
574
575 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
576 fattr->cf_dacls =
577 posix_acl_alloc(default_acl_state.users->n +
578 default_acl_state.groups->n + 4, GFP_KERNEL);
579 if (fattr->cf_dacls) {
580 cf_pdace = fattr->cf_dacls->a_entries;
581 posix_state_to_acl(&default_acl_state, cf_pdace);
582 }
583 }
584 }
585 free_acl_state(&acl_state);
586 free_acl_state(&default_acl_state);
587 }
588
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)589 static void set_posix_acl_entries_dacl(struct mnt_idmap *idmap,
590 struct smb_ace *pndace,
591 struct smb_fattr *fattr, u32 *num_aces,
592 u16 *size, u32 nt_aces_num)
593 {
594 struct posix_acl_entry *pace;
595 struct smb_sid *sid;
596 struct smb_ace *ntace;
597 int i, j;
598
599 if (!fattr->cf_acls)
600 goto posix_default_acl;
601
602 pace = fattr->cf_acls->a_entries;
603 for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) {
604 int flags = 0;
605
606 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
607 if (!sid)
608 break;
609
610 if (pace->e_tag == ACL_USER) {
611 uid_t uid;
612 unsigned int sid_type = SIDOWNER;
613
614 uid = posix_acl_uid_translate(idmap, pace);
615 if (!uid)
616 sid_type = SIDUNIX_USER;
617 id_to_sid(uid, sid_type, sid);
618 } else if (pace->e_tag == ACL_GROUP) {
619 gid_t gid;
620
621 gid = posix_acl_gid_translate(idmap, pace);
622 id_to_sid(gid, SIDUNIX_GROUP, sid);
623 } else if (pace->e_tag == ACL_OTHER && !nt_aces_num) {
624 smb_copy_sid(sid, &sid_everyone);
625 } else {
626 kfree(sid);
627 continue;
628 }
629 ntace = pndace;
630 for (j = 0; j < nt_aces_num; j++) {
631 if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] ==
632 sid->sub_auth[sid->num_subauth - 1])
633 goto pass_same_sid;
634 ntace = (struct smb_ace *)((char *)ntace +
635 le16_to_cpu(ntace->size));
636 }
637
638 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER)
639 flags = 0x03;
640
641 ntace = (struct smb_ace *)((char *)pndace + *size);
642 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags,
643 pace->e_perm, 0777);
644 (*num_aces)++;
645 if (pace->e_tag == ACL_USER)
646 ntace->access_req |=
647 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
648
649 if (S_ISDIR(fattr->cf_mode) &&
650 (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) {
651 ntace = (struct smb_ace *)((char *)pndace + *size);
652 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED,
653 0x03, pace->e_perm, 0777);
654 (*num_aces)++;
655 if (pace->e_tag == ACL_USER)
656 ntace->access_req |=
657 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
658 }
659
660 pass_same_sid:
661 kfree(sid);
662 }
663
664 if (nt_aces_num)
665 return;
666
667 posix_default_acl:
668 if (!fattr->cf_dacls)
669 return;
670
671 pace = fattr->cf_dacls->a_entries;
672 for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) {
673 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
674 if (!sid)
675 break;
676
677 if (pace->e_tag == ACL_USER) {
678 uid_t uid;
679
680 uid = posix_acl_uid_translate(idmap, pace);
681 id_to_sid(uid, SIDCREATOR_OWNER, sid);
682 } else if (pace->e_tag == ACL_GROUP) {
683 gid_t gid;
684
685 gid = posix_acl_gid_translate(idmap, pace);
686 id_to_sid(gid, SIDCREATOR_GROUP, sid);
687 } else {
688 kfree(sid);
689 continue;
690 }
691
692 ntace = (struct smb_ace *)((char *)pndace + *size);
693 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b,
694 pace->e_perm, 0777);
695 (*num_aces)++;
696 if (pace->e_tag == ACL_USER)
697 ntace->access_req |=
698 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
699 kfree(sid);
700 }
701 }
702
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)703 static void set_ntacl_dacl(struct mnt_idmap *idmap,
704 struct smb_acl *pndacl,
705 struct smb_acl *nt_dacl,
706 unsigned int aces_size,
707 const struct smb_sid *pownersid,
708 const struct smb_sid *pgrpsid,
709 struct smb_fattr *fattr)
710 {
711 struct smb_ace *ntace, *pndace;
712 int nt_num_aces = le32_to_cpu(nt_dacl->num_aces), num_aces = 0;
713 unsigned short size = 0;
714 int i;
715
716 pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
717 if (nt_num_aces) {
718 ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl));
719 for (i = 0; i < nt_num_aces; i++) {
720 unsigned short nt_ace_size;
721
722 if (offsetof(struct smb_ace, access_req) > aces_size)
723 break;
724
725 nt_ace_size = le16_to_cpu(ntace->size);
726 if (nt_ace_size > aces_size)
727 break;
728
729 memcpy((char *)pndace + size, ntace, nt_ace_size);
730 size += nt_ace_size;
731 aces_size -= nt_ace_size;
732 ntace = (struct smb_ace *)((char *)ntace + nt_ace_size);
733 num_aces++;
734 }
735 }
736
737 set_posix_acl_entries_dacl(idmap, pndace, fattr,
738 &num_aces, &size, nt_num_aces);
739 pndacl->num_aces = cpu_to_le32(num_aces);
740 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
741 }
742
set_mode_dacl(struct mnt_idmap * idmap,struct smb_acl * pndacl,struct smb_fattr * fattr)743 static void set_mode_dacl(struct mnt_idmap *idmap,
744 struct smb_acl *pndacl, struct smb_fattr *fattr)
745 {
746 struct smb_ace *pace, *pndace;
747 u32 num_aces = 0;
748 u16 size = 0, ace_size = 0;
749 uid_t uid;
750 const struct smb_sid *sid;
751
752 pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
753
754 if (fattr->cf_acls) {
755 set_posix_acl_entries_dacl(idmap, pndace, fattr,
756 &num_aces, &size, num_aces);
757 goto out;
758 }
759
760 /* owner RID */
761 uid = from_kuid(&init_user_ns, fattr->cf_uid);
762 if (uid)
763 sid = &server_conf.domain_sid;
764 else
765 sid = &sid_unix_users;
766 ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0,
767 fattr->cf_mode, 0700);
768 pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid);
769 pace->size = cpu_to_le16(ace_size + 4);
770 size += le16_to_cpu(pace->size);
771 pace = (struct smb_ace *)((char *)pndace + size);
772
773 /* Group RID */
774 ace_size = fill_ace_for_sid(pace, &sid_unix_groups,
775 ACCESS_ALLOWED, 0, fattr->cf_mode, 0070);
776 pace->sid.sub_auth[pace->sid.num_subauth++] =
777 cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid));
778 pace->size = cpu_to_le16(ace_size + 4);
779 size += le16_to_cpu(pace->size);
780 pace = (struct smb_ace *)((char *)pndace + size);
781 num_aces = 3;
782
783 if (S_ISDIR(fattr->cf_mode)) {
784 pace = (struct smb_ace *)((char *)pndace + size);
785
786 /* creator owner */
787 size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED,
788 0x0b, fattr->cf_mode, 0700);
789 pace = (struct smb_ace *)((char *)pndace + size);
790
791 /* creator group */
792 size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED,
793 0x0b, fattr->cf_mode, 0070);
794 pace = (struct smb_ace *)((char *)pndace + size);
795 num_aces = 5;
796 }
797
798 /* other */
799 size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0,
800 fattr->cf_mode, 0007);
801
802 out:
803 pndacl->num_aces = cpu_to_le32(num_aces);
804 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
805 }
806
parse_sid(struct smb_sid * psid,char * end_of_acl)807 static int parse_sid(struct smb_sid *psid, char *end_of_acl)
808 {
809 /*
810 * validate that we do not go past end of ACL - sid must be at least 8
811 * bytes long (assuming no sub-auths - e.g. the null SID
812 */
813 if (end_of_acl < (char *)psid + 8) {
814 pr_err("ACL too small to parse SID %p\n", psid);
815 return -EINVAL;
816 }
817
818 if (!psid->num_subauth)
819 return 0;
820
821 if (psid->num_subauth > SID_MAX_SUB_AUTHORITIES ||
822 end_of_acl < (char *)psid + 8 + sizeof(__le32) * psid->num_subauth)
823 return -EINVAL;
824
825 return 0;
826 }
827
828 /* Convert CIFS ACL to POSIX form */
parse_sec_desc(struct mnt_idmap * idmap,struct smb_ntsd * pntsd,int acl_len,struct smb_fattr * fattr)829 int parse_sec_desc(struct mnt_idmap *idmap, struct smb_ntsd *pntsd,
830 int acl_len, struct smb_fattr *fattr)
831 {
832 int rc = 0;
833 struct smb_sid *owner_sid_ptr, *group_sid_ptr;
834 struct smb_acl *dacl_ptr; /* no need for SACL ptr */
835 char *end_of_acl = ((char *)pntsd) + acl_len;
836 __u32 dacloffset;
837 int pntsd_type;
838
839 if (!pntsd)
840 return -EIO;
841
842 if (acl_len < sizeof(struct smb_ntsd))
843 return -EINVAL;
844
845 owner_sid_ptr = (struct smb_sid *)((char *)pntsd +
846 le32_to_cpu(pntsd->osidoffset));
847 group_sid_ptr = (struct smb_sid *)((char *)pntsd +
848 le32_to_cpu(pntsd->gsidoffset));
849 dacloffset = le32_to_cpu(pntsd->dacloffset);
850 dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset);
851 ksmbd_debug(SMB,
852 "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n",
853 pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
854 le32_to_cpu(pntsd->gsidoffset),
855 le32_to_cpu(pntsd->sacloffset), dacloffset);
856
857 pntsd_type = le16_to_cpu(pntsd->type);
858 if (!(pntsd_type & DACL_PRESENT)) {
859 ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n");
860 return rc;
861 }
862
863 pntsd->type = cpu_to_le16(DACL_PRESENT);
864
865 if (pntsd->osidoffset) {
866 if (le32_to_cpu(pntsd->osidoffset) < sizeof(struct smb_ntsd))
867 return -EINVAL;
868
869 rc = parse_sid(owner_sid_ptr, end_of_acl);
870 if (rc) {
871 pr_err("%s: Error %d parsing Owner SID\n", __func__, rc);
872 return rc;
873 }
874
875 rc = sid_to_id(idmap, owner_sid_ptr, SIDOWNER, fattr);
876 if (rc) {
877 pr_err("%s: Error %d mapping Owner SID to uid\n",
878 __func__, rc);
879 owner_sid_ptr = NULL;
880 }
881 }
882
883 if (pntsd->gsidoffset) {
884 if (le32_to_cpu(pntsd->gsidoffset) < sizeof(struct smb_ntsd))
885 return -EINVAL;
886
887 rc = parse_sid(group_sid_ptr, end_of_acl);
888 if (rc) {
889 pr_err("%s: Error %d mapping Owner SID to gid\n",
890 __func__, rc);
891 return rc;
892 }
893 rc = sid_to_id(idmap, group_sid_ptr, SIDUNIX_GROUP, fattr);
894 if (rc) {
895 pr_err("%s: Error %d mapping Group SID to gid\n",
896 __func__, rc);
897 group_sid_ptr = NULL;
898 }
899 }
900
901 if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) ==
902 (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ))
903 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
904 if (pntsd_type & DACL_PROTECTED)
905 pntsd->type |= cpu_to_le16(DACL_PROTECTED);
906
907 if (dacloffset) {
908 if (dacloffset < sizeof(struct smb_ntsd))
909 return -EINVAL;
910
911 parse_dacl(idmap, dacl_ptr, end_of_acl,
912 owner_sid_ptr, group_sid_ptr, fattr);
913 }
914
915 return 0;
916 }
917
918 /* 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)919 int build_sec_desc(struct mnt_idmap *idmap,
920 struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
921 int ppntsd_size, int addition_info, __u32 *secdesclen,
922 struct smb_fattr *fattr)
923 {
924 int rc = 0;
925 __u32 offset;
926 struct smb_sid *owner_sid_ptr, *group_sid_ptr;
927 struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr;
928 struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */
929 uid_t uid;
930 gid_t gid;
931 unsigned int sid_type = SIDOWNER;
932
933 nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
934 if (!nowner_sid_ptr)
935 return -ENOMEM;
936
937 uid = from_kuid(&init_user_ns, fattr->cf_uid);
938 if (!uid)
939 sid_type = SIDUNIX_USER;
940 id_to_sid(uid, sid_type, nowner_sid_ptr);
941
942 ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
943 if (!ngroup_sid_ptr) {
944 kfree(nowner_sid_ptr);
945 return -ENOMEM;
946 }
947
948 gid = from_kgid(&init_user_ns, fattr->cf_gid);
949 id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr);
950
951 offset = sizeof(struct smb_ntsd);
952 pntsd->sacloffset = 0;
953 pntsd->revision = cpu_to_le16(1);
954 pntsd->type = cpu_to_le16(SELF_RELATIVE);
955 if (ppntsd)
956 pntsd->type |= ppntsd->type;
957
958 if (addition_info & OWNER_SECINFO) {
959 pntsd->osidoffset = cpu_to_le32(offset);
960 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
961 smb_copy_sid(owner_sid_ptr, nowner_sid_ptr);
962 offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4);
963 }
964
965 if (addition_info & GROUP_SECINFO) {
966 pntsd->gsidoffset = cpu_to_le32(offset);
967 group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
968 smb_copy_sid(group_sid_ptr, ngroup_sid_ptr);
969 offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4);
970 }
971
972 if (addition_info & DACL_SECINFO) {
973 pntsd->type |= cpu_to_le16(DACL_PRESENT);
974 dacl_ptr = (struct smb_acl *)((char *)pntsd + offset);
975 dacl_ptr->revision = cpu_to_le16(2);
976 dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl));
977 dacl_ptr->num_aces = 0;
978
979 if (!ppntsd) {
980 set_mode_dacl(idmap, dacl_ptr, fattr);
981 } else {
982 struct smb_acl *ppdacl_ptr;
983 unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset);
984 int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset;
985
986 if (!dacl_offset ||
987 (dacl_offset + sizeof(struct smb_acl) > ppntsd_size))
988 goto out;
989
990 ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset);
991 ppdacl_size = le16_to_cpu(ppdacl_ptr->size);
992 if (ppdacl_size > ntacl_size ||
993 ppdacl_size < sizeof(struct smb_acl))
994 goto out;
995
996 set_ntacl_dacl(idmap, dacl_ptr, ppdacl_ptr,
997 ntacl_size - sizeof(struct smb_acl),
998 nowner_sid_ptr, ngroup_sid_ptr,
999 fattr);
1000 }
1001 pntsd->dacloffset = cpu_to_le32(offset);
1002 offset += le16_to_cpu(dacl_ptr->size);
1003 }
1004
1005 out:
1006 kfree(nowner_sid_ptr);
1007 kfree(ngroup_sid_ptr);
1008 *secdesclen = offset;
1009 return rc;
1010 }
1011
smb_set_ace(struct smb_ace * ace,const struct smb_sid * sid,u8 type,u8 flags,__le32 access_req)1012 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type,
1013 u8 flags, __le32 access_req)
1014 {
1015 ace->type = type;
1016 ace->flags = flags;
1017 ace->access_req = access_req;
1018 smb_copy_sid(&ace->sid, sid);
1019 ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + (sid->num_subauth * 4));
1020 }
1021
smb_inherit_dacl(struct ksmbd_conn * conn,const struct path * path,unsigned int uid,unsigned int gid)1022 int smb_inherit_dacl(struct ksmbd_conn *conn,
1023 const struct path *path,
1024 unsigned int uid, unsigned int gid)
1025 {
1026 const struct smb_sid *psid, *creator = NULL;
1027 struct smb_ace *parent_aces, *aces;
1028 struct smb_acl *parent_pdacl;
1029 struct smb_ntsd *parent_pntsd = NULL;
1030 struct smb_sid owner_sid, group_sid;
1031 struct dentry *parent = path->dentry->d_parent;
1032 struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1033 int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size;
1034 int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size;
1035 char *aces_base;
1036 bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
1037
1038 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1039 parent, &parent_pntsd);
1040 if (pntsd_size <= 0)
1041 return -ENOENT;
1042 dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
1043 if (!dacloffset || (dacloffset + sizeof(struct smb_acl) > pntsd_size)) {
1044 rc = -EINVAL;
1045 goto free_parent_pntsd;
1046 }
1047
1048 parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset);
1049 acl_len = pntsd_size - dacloffset;
1050 num_aces = le32_to_cpu(parent_pdacl->num_aces);
1051 pntsd_type = le16_to_cpu(parent_pntsd->type);
1052 pdacl_size = le16_to_cpu(parent_pdacl->size);
1053
1054 if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) {
1055 rc = -EINVAL;
1056 goto free_parent_pntsd;
1057 }
1058
1059 aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL);
1060 if (!aces_base) {
1061 rc = -ENOMEM;
1062 goto free_parent_pntsd;
1063 }
1064
1065 aces = (struct smb_ace *)aces_base;
1066 parent_aces = (struct smb_ace *)((char *)parent_pdacl +
1067 sizeof(struct smb_acl));
1068 aces_size = acl_len - sizeof(struct smb_acl);
1069
1070 if (pntsd_type & DACL_AUTO_INHERITED)
1071 inherited_flags = INHERITED_ACE;
1072
1073 for (i = 0; i < num_aces; i++) {
1074 int pace_size;
1075
1076 if (offsetof(struct smb_ace, access_req) > aces_size)
1077 break;
1078
1079 pace_size = le16_to_cpu(parent_aces->size);
1080 if (pace_size > aces_size)
1081 break;
1082
1083 aces_size -= pace_size;
1084
1085 flags = parent_aces->flags;
1086 if (!smb_inherit_flags(flags, is_dir))
1087 goto pass;
1088 if (is_dir) {
1089 flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE);
1090 if (!(flags & CONTAINER_INHERIT_ACE))
1091 flags |= INHERIT_ONLY_ACE;
1092 if (flags & NO_PROPAGATE_INHERIT_ACE)
1093 flags = 0;
1094 } else {
1095 flags = 0;
1096 }
1097
1098 if (!compare_sids(&creator_owner, &parent_aces->sid)) {
1099 creator = &creator_owner;
1100 id_to_sid(uid, SIDOWNER, &owner_sid);
1101 psid = &owner_sid;
1102 } else if (!compare_sids(&creator_group, &parent_aces->sid)) {
1103 creator = &creator_group;
1104 id_to_sid(gid, SIDUNIX_GROUP, &group_sid);
1105 psid = &group_sid;
1106 } else {
1107 creator = NULL;
1108 psid = &parent_aces->sid;
1109 }
1110
1111 if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) {
1112 smb_set_ace(aces, psid, parent_aces->type, inherited_flags,
1113 parent_aces->access_req);
1114 nt_size += le16_to_cpu(aces->size);
1115 ace_cnt++;
1116 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1117 flags |= INHERIT_ONLY_ACE;
1118 psid = creator;
1119 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) {
1120 psid = &parent_aces->sid;
1121 }
1122
1123 smb_set_ace(aces, psid, parent_aces->type, flags | inherited_flags,
1124 parent_aces->access_req);
1125 nt_size += le16_to_cpu(aces->size);
1126 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1127 ace_cnt++;
1128 pass:
1129 parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size);
1130 }
1131
1132 if (nt_size > 0) {
1133 struct smb_ntsd *pntsd;
1134 struct smb_acl *pdacl;
1135 struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL;
1136 int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size;
1137 int pntsd_alloc_size;
1138
1139 if (parent_pntsd->osidoffset) {
1140 powner_sid = (struct smb_sid *)((char *)parent_pntsd +
1141 le32_to_cpu(parent_pntsd->osidoffset));
1142 powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4);
1143 }
1144 if (parent_pntsd->gsidoffset) {
1145 pgroup_sid = (struct smb_sid *)((char *)parent_pntsd +
1146 le32_to_cpu(parent_pntsd->gsidoffset));
1147 pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4);
1148 }
1149
1150 pntsd_alloc_size = sizeof(struct smb_ntsd) + powner_sid_size +
1151 pgroup_sid_size + sizeof(struct smb_acl) + nt_size;
1152
1153 pntsd = kzalloc(pntsd_alloc_size, GFP_KERNEL);
1154 if (!pntsd) {
1155 rc = -ENOMEM;
1156 goto free_aces_base;
1157 }
1158
1159 pntsd->revision = cpu_to_le16(1);
1160 pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT);
1161 if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED)
1162 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
1163 pntsd_size = sizeof(struct smb_ntsd);
1164 pntsd->osidoffset = parent_pntsd->osidoffset;
1165 pntsd->gsidoffset = parent_pntsd->gsidoffset;
1166 pntsd->dacloffset = parent_pntsd->dacloffset;
1167
1168 if ((u64)le32_to_cpu(pntsd->osidoffset) + powner_sid_size >
1169 pntsd_alloc_size) {
1170 rc = -EINVAL;
1171 kfree(pntsd);
1172 goto free_aces_base;
1173 }
1174
1175 if ((u64)le32_to_cpu(pntsd->gsidoffset) + pgroup_sid_size >
1176 pntsd_alloc_size) {
1177 rc = -EINVAL;
1178 kfree(pntsd);
1179 goto free_aces_base;
1180 }
1181
1182 if ((u64)le32_to_cpu(pntsd->dacloffset) + sizeof(struct smb_acl) + nt_size >
1183 pntsd_alloc_size) {
1184 rc = -EINVAL;
1185 kfree(pntsd);
1186 goto free_aces_base;
1187 }
1188
1189 if (pntsd->osidoffset) {
1190 struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd +
1191 le32_to_cpu(pntsd->osidoffset));
1192 memcpy(owner_sid, powner_sid, powner_sid_size);
1193 pntsd_size += powner_sid_size;
1194 }
1195
1196 if (pntsd->gsidoffset) {
1197 struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd +
1198 le32_to_cpu(pntsd->gsidoffset));
1199 memcpy(group_sid, pgroup_sid, pgroup_sid_size);
1200 pntsd_size += pgroup_sid_size;
1201 }
1202
1203 if (pntsd->dacloffset) {
1204 struct smb_ace *pace;
1205
1206 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1207 pdacl->revision = cpu_to_le16(2);
1208 pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size);
1209 pdacl->num_aces = cpu_to_le32(ace_cnt);
1210 pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1211 memcpy(pace, aces_base, nt_size);
1212 pntsd_size += sizeof(struct smb_acl) + nt_size;
1213 }
1214
1215 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, pntsd_size, false);
1216 kfree(pntsd);
1217 }
1218
1219 free_aces_base:
1220 kfree(aces_base);
1221 free_parent_pntsd:
1222 kfree(parent_pntsd);
1223 return rc;
1224 }
1225
smb_inherit_flags(int flags,bool is_dir)1226 bool smb_inherit_flags(int flags, bool is_dir)
1227 {
1228 if (!is_dir)
1229 return (flags & OBJECT_INHERIT_ACE) != 0;
1230
1231 if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE))
1232 return true;
1233
1234 if (flags & CONTAINER_INHERIT_ACE)
1235 return true;
1236 return false;
1237 }
1238
smb_check_perm_dacl(struct ksmbd_conn * conn,const struct path * path,__le32 * pdaccess,int uid)1239 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
1240 __le32 *pdaccess, int uid)
1241 {
1242 struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1243 struct smb_ntsd *pntsd = NULL;
1244 struct smb_acl *pdacl;
1245 struct posix_acl *posix_acls;
1246 int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size, dacl_offset;
1247 struct smb_sid sid;
1248 int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
1249 struct smb_ace *ace;
1250 int i, found = 0;
1251 unsigned int access_bits = 0;
1252 struct smb_ace *others_ace = NULL;
1253 struct posix_acl_entry *pa_entry;
1254 unsigned int sid_type = SIDOWNER;
1255 unsigned short ace_size;
1256
1257 ksmbd_debug(SMB, "check permission using windows acl\n");
1258 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1259 path->dentry, &pntsd);
1260 if (pntsd_size <= 0 || !pntsd)
1261 goto err_out;
1262
1263 dacl_offset = le32_to_cpu(pntsd->dacloffset);
1264 if (!dacl_offset ||
1265 (dacl_offset + sizeof(struct smb_acl) > pntsd_size))
1266 goto err_out;
1267
1268 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1269 acl_size = pntsd_size - dacl_offset;
1270 pdacl_size = le16_to_cpu(pdacl->size);
1271
1272 if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl))
1273 goto err_out;
1274
1275 if (!pdacl->num_aces) {
1276 if (!(pdacl_size - sizeof(struct smb_acl)) &&
1277 *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) {
1278 rc = -EACCES;
1279 goto err_out;
1280 }
1281 goto err_out;
1282 }
1283
1284 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
1285 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1286 DELETE;
1287
1288 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1289 aces_size = acl_size - sizeof(struct smb_acl);
1290 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1291 if (offsetof(struct smb_ace, access_req) > aces_size)
1292 break;
1293 ace_size = le16_to_cpu(ace->size);
1294 if (ace_size > aces_size)
1295 break;
1296 aces_size -= ace_size;
1297 granted |= le32_to_cpu(ace->access_req);
1298 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1299 }
1300
1301 if (!pdacl->num_aces)
1302 granted = GENERIC_ALL_FLAGS;
1303 }
1304
1305 if (!uid)
1306 sid_type = SIDUNIX_USER;
1307 id_to_sid(uid, sid_type, &sid);
1308
1309 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1310 aces_size = acl_size - sizeof(struct smb_acl);
1311 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1312 if (offsetof(struct smb_ace, access_req) > aces_size)
1313 break;
1314 ace_size = le16_to_cpu(ace->size);
1315 if (ace_size > aces_size)
1316 break;
1317 aces_size -= ace_size;
1318
1319 if (!compare_sids(&sid, &ace->sid) ||
1320 !compare_sids(&sid_unix_NFS_mode, &ace->sid)) {
1321 found = 1;
1322 break;
1323 }
1324 if (!compare_sids(&sid_everyone, &ace->sid))
1325 others_ace = ace;
1326
1327 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1328 }
1329
1330 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
1331 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1332 DELETE;
1333
1334 granted |= le32_to_cpu(ace->access_req);
1335
1336 if (!pdacl->num_aces)
1337 granted = GENERIC_ALL_FLAGS;
1338 }
1339
1340 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
1341 posix_acls = get_inode_acl(d_inode(path->dentry), ACL_TYPE_ACCESS);
1342 if (!IS_ERR_OR_NULL(posix_acls) && !found) {
1343 unsigned int id = -1;
1344
1345 pa_entry = posix_acls->a_entries;
1346 for (i = 0; i < posix_acls->a_count; i++, pa_entry++) {
1347 if (pa_entry->e_tag == ACL_USER)
1348 id = posix_acl_uid_translate(idmap, pa_entry);
1349 else if (pa_entry->e_tag == ACL_GROUP)
1350 id = posix_acl_gid_translate(idmap, pa_entry);
1351 else
1352 continue;
1353
1354 if (id == uid) {
1355 mode_to_access_flags(pa_entry->e_perm,
1356 0777,
1357 &access_bits);
1358 if (!access_bits)
1359 access_bits =
1360 SET_MINIMUM_RIGHTS;
1361 posix_acl_release(posix_acls);
1362 goto check_access_bits;
1363 }
1364 }
1365 }
1366 if (!IS_ERR_OR_NULL(posix_acls))
1367 posix_acl_release(posix_acls);
1368 }
1369
1370 if (!found) {
1371 if (others_ace) {
1372 ace = others_ace;
1373 } else {
1374 ksmbd_debug(SMB, "Can't find corresponding sid\n");
1375 rc = -EACCES;
1376 goto err_out;
1377 }
1378 }
1379
1380 switch (ace->type) {
1381 case ACCESS_ALLOWED_ACE_TYPE:
1382 access_bits = le32_to_cpu(ace->access_req);
1383 break;
1384 case ACCESS_DENIED_ACE_TYPE:
1385 case ACCESS_DENIED_CALLBACK_ACE_TYPE:
1386 access_bits = le32_to_cpu(~ace->access_req);
1387 break;
1388 }
1389
1390 check_access_bits:
1391 if (granted &
1392 ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) {
1393 ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n",
1394 granted, le32_to_cpu(ace->access_req));
1395 rc = -EACCES;
1396 goto err_out;
1397 }
1398
1399 *pdaccess = cpu_to_le32(granted);
1400 err_out:
1401 kfree(pntsd);
1402 return rc;
1403 }
1404
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)1405 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
1406 const struct path *path, struct smb_ntsd *pntsd, int ntsd_len,
1407 bool type_check, bool get_write)
1408 {
1409 int rc;
1410 struct smb_fattr fattr = {{0}};
1411 struct inode *inode = d_inode(path->dentry);
1412 struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1413 struct iattr newattrs;
1414
1415 fattr.cf_uid = INVALID_UID;
1416 fattr.cf_gid = INVALID_GID;
1417 fattr.cf_mode = inode->i_mode;
1418
1419 rc = parse_sec_desc(idmap, pntsd, ntsd_len, &fattr);
1420 if (rc)
1421 goto out;
1422
1423 newattrs.ia_valid = ATTR_CTIME;
1424 if (!uid_eq(fattr.cf_uid, INVALID_UID)) {
1425 newattrs.ia_valid |= ATTR_UID;
1426 newattrs.ia_uid = fattr.cf_uid;
1427 }
1428 if (!gid_eq(fattr.cf_gid, INVALID_GID)) {
1429 newattrs.ia_valid |= ATTR_GID;
1430 newattrs.ia_gid = fattr.cf_gid;
1431 }
1432 newattrs.ia_valid |= ATTR_MODE;
1433 newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
1434
1435 ksmbd_vfs_remove_acl_xattrs(idmap, path);
1436 /* Update posix acls */
1437 if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) {
1438 rc = set_posix_acl(idmap, path->dentry,
1439 ACL_TYPE_ACCESS, fattr.cf_acls);
1440 if (rc < 0)
1441 ksmbd_debug(SMB,
1442 "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
1443 rc);
1444 if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) {
1445 rc = set_posix_acl(idmap, path->dentry,
1446 ACL_TYPE_DEFAULT, fattr.cf_dacls);
1447 if (rc)
1448 ksmbd_debug(SMB,
1449 "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n",
1450 rc);
1451 }
1452 }
1453
1454 inode_lock(inode);
1455 rc = notify_change(idmap, path->dentry, &newattrs, NULL);
1456 inode_unlock(inode);
1457 if (rc)
1458 goto out;
1459
1460 /* Check it only calling from SD BUFFER context */
1461 if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT))
1462 goto out;
1463
1464 if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) {
1465 /* Update WinACL in xattr */
1466 ksmbd_vfs_remove_sd_xattrs(idmap, path);
1467 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, ntsd_len,
1468 get_write);
1469 }
1470
1471 out:
1472 posix_acl_release(fattr.cf_acls);
1473 posix_acl_release(fattr.cf_dacls);
1474 return rc;
1475 }
1476
ksmbd_init_domain(u32 * sub_auth)1477 void ksmbd_init_domain(u32 *sub_auth)
1478 {
1479 int i;
1480
1481 memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid));
1482 for (i = 0; i < 3; ++i)
1483 server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]);
1484 }
1485