1 // SPDX-License-Identifier: LGPL-2.1+
3 * Copyright (C) International Business Machines Corp., 2007,2008
5 * Copyright (C) 2020 Samsung Electronics Co., Ltd.
10 #include <linux/slab.h>
11 #include <linux/string.h>
12 #include <linux/mnt_idmapping.h>
15 #include "smb_common.h"
18 #include "mgmt/share_config.h"
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} };
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)} };
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)} };
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} };
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} };
47 * See http://technet.microsoft.com/en-us/library/hh509017(v=ws.10).aspx
50 /* S-1-5-88 MS NFS and Apple style UID/GID/mode */
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},
55 cpu_to_le32(1), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
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},
60 cpu_to_le32(2), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
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},
65 cpu_to_le32(3), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
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.
71 int compare_sids(const struct smb_sid *ctsid, const struct smb_sid *cwsid)
74 int num_subauth, num_sat, num_saw;
79 /* compare the revision */
80 if (ctsid->revision != cwsid->revision) {
81 if (ctsid->revision > cwsid->revision)
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])
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;
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]))
113 return 0; /* sids compare/match */
116 static void smb_copy_sid(struct smb_sid *dst, const struct smb_sid *src)
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];
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
133 static umode_t access_flags_to_mode(struct smb_fattr *fattr, __le32 ace_flags,
136 __u32 flags = le32_to_cpu(ace_flags);
139 if (flags & GENERIC_ALL) {
141 ksmbd_debug(SMB, "all perms\n");
145 if ((flags & GENERIC_READ) || (flags & FILE_READ_RIGHTS))
147 if ((flags & GENERIC_WRITE) || (flags & FILE_WRITE_RIGHTS)) {
149 if (S_ISDIR(fattr->cf_mode))
152 if ((flags & GENERIC_EXECUTE) || (flags & FILE_EXEC_RIGHTS))
155 if (type == ACCESS_DENIED_ACE_TYPE || type == ACCESS_DENIED_OBJECT_ACE_TYPE)
158 ksmbd_debug(SMB, "access flags 0x%x mode now %04o\n", flags, mode);
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.
168 static void mode_to_access_flags(umode_t mode, umode_t bits_to_use,
171 /* reset access mask */
174 /* bits to use are either S_IRWXU or S_IRWXG or S_IRWXO */
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
183 *pace_flags |= SET_FILE_READ_RIGHTS;
185 *pace_flags |= FILE_WRITE_RIGHTS;
187 *pace_flags |= SET_FILE_EXEC_RIGHTS;
189 ksmbd_debug(SMB, "mode: %o, access flags now 0x%x\n",
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)
199 __u32 access_req = 0;
202 pntace->flags = flags;
203 mode_to_access_flags(mode, bits, &access_req);
205 access_req = SET_MINIMUM_RIGHTS;
206 pntace->access_req = cpu_to_le32(access_req);
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];
215 size = 1 + 1 + 2 + 4 + 1 + 1 + 6 + (psid->num_subauth * 4);
216 pntace->size = cpu_to_le16(size);
221 void id_to_sid(unsigned int cid, uint sidtype, struct smb_sid *ssid)
225 smb_copy_sid(ssid, &server_conf.domain_sid);
228 smb_copy_sid(ssid, &sid_unix_users);
231 smb_copy_sid(ssid, &sid_unix_groups);
233 case SIDCREATOR_OWNER:
234 smb_copy_sid(ssid, &creator_owner);
236 case SIDCREATOR_GROUP:
237 smb_copy_sid(ssid, &creator_group);
240 smb_copy_sid(ssid, &sid_unix_NFS_users);
243 smb_copy_sid(ssid, &sid_unix_NFS_groups);
246 smb_copy_sid(ssid, &sid_unix_NFS_mode);
253 ssid->sub_auth[ssid->num_subauth] = cpu_to_le32(cid);
257 static int sid_to_id(struct user_namespace *user_ns,
258 struct smb_sid *psid, uint sidtype,
259 struct smb_fattr *fattr)
264 * If we have too many subauthorities, then something is really wrong.
265 * Just return an error.
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);
273 if (sidtype == SIDOWNER) {
277 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
278 uid = mapped_kuid_user(user_ns, &init_user_ns, KUIDT_INIT(id));
279 if (uid_valid(uid)) {
287 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
288 gid = mapped_kgid_user(user_ns, &init_user_ns, KGIDT_INIT(id));
289 if (gid_valid(gid)) {
298 void posix_state_to_acl(struct posix_acl_state *state,
299 struct posix_acl_entry *pace)
303 pace->e_tag = ACL_USER_OBJ;
304 pace->e_perm = state->owner.allow;
305 for (i = 0; i < state->users->n; i++) {
307 pace->e_tag = ACL_USER;
308 pace->e_uid = state->users->aces[i].uid;
309 pace->e_perm = state->users->aces[i].perms.allow;
313 pace->e_tag = ACL_GROUP_OBJ;
314 pace->e_perm = state->group.allow;
316 for (i = 0; i < state->groups->n; i++) {
318 pace->e_tag = ACL_GROUP;
319 pace->e_gid = state->groups->aces[i].gid;
320 pace->e_perm = state->groups->aces[i].perms.allow;
323 if (state->users->n || state->groups->n) {
325 pace->e_tag = ACL_MASK;
326 pace->e_perm = state->mask.allow;
330 pace->e_tag = ACL_OTHER;
331 pace->e_perm = state->other.allow;
334 int init_acl_state(struct posix_acl_state *state, int cnt)
338 memset(state, 0, sizeof(struct posix_acl_state));
340 * In the worst case, each individual acl could be for a distinct
341 * named user or group, but we don't know which, so we allocate
342 * enough space for either:
344 alloc = sizeof(struct posix_ace_state_array)
345 + cnt * sizeof(struct posix_user_ace_state);
346 state->users = kzalloc(alloc, GFP_KERNEL);
349 state->groups = kzalloc(alloc, GFP_KERNEL);
350 if (!state->groups) {
357 void free_acl_state(struct posix_acl_state *state)
360 kfree(state->groups);
363 static void parse_dacl(struct user_namespace *user_ns,
364 struct smb_acl *pdacl, char *end_of_acl,
365 struct smb_sid *pownersid, struct smb_sid *pgrpsid,
366 struct smb_fattr *fattr)
370 unsigned int acl_size;
372 struct smb_ace **ppace;
373 struct posix_acl_entry *cf_pace, *cf_pdace;
374 struct posix_acl_state acl_state, default_acl_state;
375 umode_t mode = 0, acl_mode;
376 bool owner_found = false, group_found = false, others_found = false;
381 /* validate that we do not go past end of acl */
382 if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) ||
383 end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) {
384 pr_err("ACL too small to parse DACL\n");
388 ksmbd_debug(SMB, "DACL revision %d size %d num aces %d\n",
389 le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size),
390 le32_to_cpu(pdacl->num_aces));
392 acl_base = (char *)pdacl;
393 acl_size = sizeof(struct smb_acl);
395 num_aces = le32_to_cpu(pdacl->num_aces);
399 if (num_aces > ULONG_MAX / sizeof(struct smb_ace *))
402 ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL);
406 ret = init_acl_state(&acl_state, num_aces);
409 ret = init_acl_state(&default_acl_state, num_aces);
411 free_acl_state(&acl_state);
416 * reset rwx permissions for user/group/other.
417 * Also, if num_aces is 0 i.e. DACL has no ACEs,
418 * user/group/other have no permissions
420 for (i = 0; i < num_aces; ++i) {
421 if (end_of_acl - acl_base < acl_size)
424 ppace[i] = (struct smb_ace *)(acl_base + acl_size);
425 acl_base = (char *)ppace[i];
426 acl_size = offsetof(struct smb_ace, sid) +
427 offsetof(struct smb_sid, sub_auth);
429 if (end_of_acl - acl_base < acl_size ||
430 ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES ||
431 (end_of_acl - acl_base <
432 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) ||
433 (le16_to_cpu(ppace[i]->size) <
434 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth))
437 acl_size = le16_to_cpu(ppace[i]->size);
438 ppace[i]->access_req =
439 smb_map_generic_desired_access(ppace[i]->access_req);
441 if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) {
443 le32_to_cpu(ppace[i]->sid.sub_auth[2]);
445 } else if (!compare_sids(&ppace[i]->sid, pownersid)) {
446 acl_mode = access_flags_to_mode(fattr,
447 ppace[i]->access_req,
456 } else if (!compare_sids(&ppace[i]->sid, pgrpsid) ||
457 ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] ==
458 DOMAIN_USER_RID_LE) {
459 acl_mode = access_flags_to_mode(fattr,
460 ppace[i]->access_req,
468 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) {
469 acl_mode = access_flags_to_mode(fattr,
470 ppace[i]->access_req,
478 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) {
480 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) {
482 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) {
485 struct smb_fattr temp_fattr;
487 acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
489 temp_fattr.cf_uid = INVALID_UID;
490 ret = sid_to_id(user_ns, &ppace[i]->sid, SIDOWNER, &temp_fattr);
491 if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) {
492 pr_err("%s: Error %d mapping Owner SID to uid\n",
497 acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
498 acl_state.users->aces[acl_state.users->n].uid =
500 acl_state.users->aces[acl_state.users->n++].perms.allow =
501 ((acl_mode & 0700) >> 6) | 0004;
502 default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
503 default_acl_state.users->aces[default_acl_state.users->n].uid =
505 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
506 ((acl_mode & 0700) >> 6) | 0004;
512 /* The owner must be set to at least read-only. */
513 acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
514 acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid;
515 acl_state.users->aces[acl_state.users->n++].perms.allow =
516 ((mode & 0700) >> 6) | 0004;
517 default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
518 default_acl_state.users->aces[default_acl_state.users->n].uid =
520 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
521 ((mode & 0700) >> 6) | 0004;
525 acl_state.group.allow = (mode & 0070) >> 3;
526 acl_state.groups->aces[acl_state.groups->n].gid =
528 acl_state.groups->aces[acl_state.groups->n++].perms.allow =
530 default_acl_state.group.allow = (mode & 0070) >> 3;
531 default_acl_state.groups->aces[default_acl_state.groups->n].gid =
533 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow =
538 fattr->cf_mode &= ~(0007);
539 fattr->cf_mode |= mode & 0007;
541 acl_state.other.allow = mode & 0007;
542 default_acl_state.other.allow = mode & 0007;
545 if (acl_state.users->n || acl_state.groups->n) {
546 acl_state.mask.allow = 0x07;
548 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
550 posix_acl_alloc(acl_state.users->n +
551 acl_state.groups->n + 4, GFP_KERNEL);
552 if (fattr->cf_acls) {
553 cf_pace = fattr->cf_acls->a_entries;
554 posix_state_to_acl(&acl_state, cf_pace);
559 if (default_acl_state.users->n || default_acl_state.groups->n) {
560 default_acl_state.mask.allow = 0x07;
562 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
564 posix_acl_alloc(default_acl_state.users->n +
565 default_acl_state.groups->n + 4, GFP_KERNEL);
566 if (fattr->cf_dacls) {
567 cf_pdace = fattr->cf_dacls->a_entries;
568 posix_state_to_acl(&default_acl_state, cf_pdace);
572 free_acl_state(&acl_state);
573 free_acl_state(&default_acl_state);
576 static void set_posix_acl_entries_dacl(struct user_namespace *user_ns,
577 struct smb_ace *pndace,
578 struct smb_fattr *fattr, u32 *num_aces,
579 u16 *size, u32 nt_aces_num)
581 struct posix_acl_entry *pace;
583 struct smb_ace *ntace;
587 goto posix_default_acl;
589 pace = fattr->cf_acls->a_entries;
590 for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) {
593 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
597 if (pace->e_tag == ACL_USER) {
599 unsigned int sid_type = SIDOWNER;
601 uid = posix_acl_uid_translate(user_ns, pace);
603 sid_type = SIDUNIX_USER;
604 id_to_sid(uid, sid_type, sid);
605 } else if (pace->e_tag == ACL_GROUP) {
608 gid = posix_acl_gid_translate(user_ns, pace);
609 id_to_sid(gid, SIDUNIX_GROUP, sid);
610 } else if (pace->e_tag == ACL_OTHER && !nt_aces_num) {
611 smb_copy_sid(sid, &sid_everyone);
617 for (j = 0; j < nt_aces_num; j++) {
618 if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] ==
619 sid->sub_auth[sid->num_subauth - 1])
621 ntace = (struct smb_ace *)((char *)ntace +
622 le16_to_cpu(ntace->size));
625 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER)
628 ntace = (struct smb_ace *)((char *)pndace + *size);
629 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags,
632 if (pace->e_tag == ACL_USER)
634 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
636 if (S_ISDIR(fattr->cf_mode) &&
637 (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) {
638 ntace = (struct smb_ace *)((char *)pndace + *size);
639 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED,
640 0x03, pace->e_perm, 0777);
642 if (pace->e_tag == ACL_USER)
644 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
655 if (!fattr->cf_dacls)
658 pace = fattr->cf_dacls->a_entries;
659 for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) {
660 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
664 if (pace->e_tag == ACL_USER) {
667 uid = posix_acl_uid_translate(user_ns, pace);
668 id_to_sid(uid, SIDCREATOR_OWNER, sid);
669 } else if (pace->e_tag == ACL_GROUP) {
672 gid = posix_acl_gid_translate(user_ns, pace);
673 id_to_sid(gid, SIDCREATOR_GROUP, sid);
679 ntace = (struct smb_ace *)((char *)pndace + *size);
680 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b,
683 if (pace->e_tag == ACL_USER)
685 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
690 static void set_ntacl_dacl(struct user_namespace *user_ns,
691 struct smb_acl *pndacl,
692 struct smb_acl *nt_dacl,
693 const struct smb_sid *pownersid,
694 const struct smb_sid *pgrpsid,
695 struct smb_fattr *fattr)
697 struct smb_ace *ntace, *pndace;
698 int nt_num_aces = le32_to_cpu(nt_dacl->num_aces), num_aces = 0;
699 unsigned short size = 0;
702 pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
704 ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl));
705 for (i = 0; i < nt_num_aces; i++) {
706 memcpy((char *)pndace + size, ntace, le16_to_cpu(ntace->size));
707 size += le16_to_cpu(ntace->size);
708 ntace = (struct smb_ace *)((char *)ntace + le16_to_cpu(ntace->size));
713 set_posix_acl_entries_dacl(user_ns, pndace, fattr,
714 &num_aces, &size, nt_num_aces);
715 pndacl->num_aces = cpu_to_le32(num_aces);
716 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
719 static void set_mode_dacl(struct user_namespace *user_ns,
720 struct smb_acl *pndacl, struct smb_fattr *fattr)
722 struct smb_ace *pace, *pndace;
724 u16 size = 0, ace_size = 0;
726 const struct smb_sid *sid;
728 pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
730 if (fattr->cf_acls) {
731 set_posix_acl_entries_dacl(user_ns, pndace, fattr,
732 &num_aces, &size, num_aces);
737 uid = from_kuid(&init_user_ns, fattr->cf_uid);
739 sid = &server_conf.domain_sid;
741 sid = &sid_unix_users;
742 ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0,
743 fattr->cf_mode, 0700);
744 pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid);
745 pace->size = cpu_to_le16(ace_size + 4);
746 size += le16_to_cpu(pace->size);
747 pace = (struct smb_ace *)((char *)pndace + size);
750 ace_size = fill_ace_for_sid(pace, &sid_unix_groups,
751 ACCESS_ALLOWED, 0, fattr->cf_mode, 0070);
752 pace->sid.sub_auth[pace->sid.num_subauth++] =
753 cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid));
754 pace->size = cpu_to_le16(ace_size + 4);
755 size += le16_to_cpu(pace->size);
756 pace = (struct smb_ace *)((char *)pndace + size);
759 if (S_ISDIR(fattr->cf_mode)) {
760 pace = (struct smb_ace *)((char *)pndace + size);
763 size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED,
764 0x0b, fattr->cf_mode, 0700);
765 pace = (struct smb_ace *)((char *)pndace + size);
768 size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED,
769 0x0b, fattr->cf_mode, 0070);
770 pace = (struct smb_ace *)((char *)pndace + size);
775 size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0,
776 fattr->cf_mode, 0007);
779 pndacl->num_aces = cpu_to_le32(num_aces);
780 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
783 static int parse_sid(struct smb_sid *psid, char *end_of_acl)
786 * validate that we do not go past end of ACL - sid must be at least 8
787 * bytes long (assuming no sub-auths - e.g. the null SID
789 if (end_of_acl < (char *)psid + 8) {
790 pr_err("ACL too small to parse SID %p\n", psid);
797 /* Convert CIFS ACL to POSIX form */
798 int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
799 int acl_len, struct smb_fattr *fattr)
802 struct smb_sid *owner_sid_ptr, *group_sid_ptr;
803 struct smb_acl *dacl_ptr; /* no need for SACL ptr */
804 char *end_of_acl = ((char *)pntsd) + acl_len;
811 if (acl_len < sizeof(struct smb_ntsd))
814 owner_sid_ptr = (struct smb_sid *)((char *)pntsd +
815 le32_to_cpu(pntsd->osidoffset));
816 group_sid_ptr = (struct smb_sid *)((char *)pntsd +
817 le32_to_cpu(pntsd->gsidoffset));
818 dacloffset = le32_to_cpu(pntsd->dacloffset);
819 dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset);
821 "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n",
822 pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
823 le32_to_cpu(pntsd->gsidoffset),
824 le32_to_cpu(pntsd->sacloffset), dacloffset);
826 pntsd_type = le16_to_cpu(pntsd->type);
827 if (!(pntsd_type & DACL_PRESENT)) {
828 ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n");
832 pntsd->type = cpu_to_le16(DACL_PRESENT);
834 if (pntsd->osidoffset) {
835 rc = parse_sid(owner_sid_ptr, end_of_acl);
837 pr_err("%s: Error %d parsing Owner SID\n", __func__, rc);
841 rc = sid_to_id(user_ns, owner_sid_ptr, SIDOWNER, fattr);
843 pr_err("%s: Error %d mapping Owner SID to uid\n",
845 owner_sid_ptr = NULL;
849 if (pntsd->gsidoffset) {
850 rc = parse_sid(group_sid_ptr, end_of_acl);
852 pr_err("%s: Error %d mapping Owner SID to gid\n",
856 rc = sid_to_id(user_ns, group_sid_ptr, SIDUNIX_GROUP, fattr);
858 pr_err("%s: Error %d mapping Group SID to gid\n",
860 group_sid_ptr = NULL;
864 if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) ==
865 (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ))
866 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
867 if (pntsd_type & DACL_PROTECTED)
868 pntsd->type |= cpu_to_le16(DACL_PROTECTED);
871 parse_dacl(user_ns, dacl_ptr, end_of_acl,
872 owner_sid_ptr, group_sid_ptr, fattr);
878 /* Convert permission bits from mode to equivalent CIFS ACL */
879 int build_sec_desc(struct user_namespace *user_ns,
880 struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
881 int addition_info, __u32 *secdesclen,
882 struct smb_fattr *fattr)
886 struct smb_sid *owner_sid_ptr, *group_sid_ptr;
887 struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr;
888 struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */
891 unsigned int sid_type = SIDOWNER;
893 nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
897 uid = from_kuid(&init_user_ns, fattr->cf_uid);
899 sid_type = SIDUNIX_USER;
900 id_to_sid(uid, sid_type, nowner_sid_ptr);
902 ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
903 if (!ngroup_sid_ptr) {
904 kfree(nowner_sid_ptr);
908 gid = from_kgid(&init_user_ns, fattr->cf_gid);
909 id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr);
911 offset = sizeof(struct smb_ntsd);
912 pntsd->sacloffset = 0;
913 pntsd->revision = cpu_to_le16(1);
914 pntsd->type = cpu_to_le16(SELF_RELATIVE);
916 pntsd->type |= ppntsd->type;
918 if (addition_info & OWNER_SECINFO) {
919 pntsd->osidoffset = cpu_to_le32(offset);
920 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
921 smb_copy_sid(owner_sid_ptr, nowner_sid_ptr);
922 offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4);
925 if (addition_info & GROUP_SECINFO) {
926 pntsd->gsidoffset = cpu_to_le32(offset);
927 group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
928 smb_copy_sid(group_sid_ptr, ngroup_sid_ptr);
929 offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4);
932 if (addition_info & DACL_SECINFO) {
933 pntsd->type |= cpu_to_le16(DACL_PRESENT);
934 dacl_ptr = (struct smb_acl *)((char *)pntsd + offset);
935 dacl_ptr->revision = cpu_to_le16(2);
936 dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl));
937 dacl_ptr->num_aces = 0;
940 set_mode_dacl(user_ns, dacl_ptr, fattr);
941 } else if (!ppntsd->dacloffset) {
944 struct smb_acl *ppdacl_ptr;
946 ppdacl_ptr = (struct smb_acl *)((char *)ppntsd +
947 le32_to_cpu(ppntsd->dacloffset));
948 set_ntacl_dacl(user_ns, dacl_ptr, ppdacl_ptr,
949 nowner_sid_ptr, ngroup_sid_ptr, fattr);
951 pntsd->dacloffset = cpu_to_le32(offset);
952 offset += le16_to_cpu(dacl_ptr->size);
956 kfree(nowner_sid_ptr);
957 kfree(ngroup_sid_ptr);
958 *secdesclen = offset;
962 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type,
963 u8 flags, __le32 access_req)
967 ace->access_req = access_req;
968 smb_copy_sid(&ace->sid, sid);
969 ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + (sid->num_subauth * 4));
972 int smb_inherit_dacl(struct ksmbd_conn *conn,
974 unsigned int uid, unsigned int gid)
976 const struct smb_sid *psid, *creator = NULL;
977 struct smb_ace *parent_aces, *aces;
978 struct smb_acl *parent_pdacl;
979 struct smb_ntsd *parent_pntsd = NULL;
980 struct smb_sid owner_sid, group_sid;
981 struct dentry *parent = path->dentry->d_parent;
982 struct user_namespace *user_ns = mnt_user_ns(path->mnt);
983 int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0;
984 int rc = 0, num_aces, dacloffset, pntsd_type, acl_len;
986 bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
988 acl_len = ksmbd_vfs_get_sd_xattr(conn, user_ns,
989 parent, &parent_pntsd);
992 dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
995 goto free_parent_pntsd;
998 parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset);
999 num_aces = le32_to_cpu(parent_pdacl->num_aces);
1000 pntsd_type = le16_to_cpu(parent_pntsd->type);
1002 aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL);
1005 goto free_parent_pntsd;
1008 aces = (struct smb_ace *)aces_base;
1009 parent_aces = (struct smb_ace *)((char *)parent_pdacl +
1010 sizeof(struct smb_acl));
1012 if (pntsd_type & DACL_AUTO_INHERITED)
1013 inherited_flags = INHERITED_ACE;
1015 for (i = 0; i < num_aces; i++) {
1016 flags = parent_aces->flags;
1017 if (!smb_inherit_flags(flags, is_dir))
1020 flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE);
1021 if (!(flags & CONTAINER_INHERIT_ACE))
1022 flags |= INHERIT_ONLY_ACE;
1023 if (flags & NO_PROPAGATE_INHERIT_ACE)
1029 if (!compare_sids(&creator_owner, &parent_aces->sid)) {
1030 creator = &creator_owner;
1031 id_to_sid(uid, SIDOWNER, &owner_sid);
1033 } else if (!compare_sids(&creator_group, &parent_aces->sid)) {
1034 creator = &creator_group;
1035 id_to_sid(gid, SIDUNIX_GROUP, &group_sid);
1039 psid = &parent_aces->sid;
1042 if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) {
1043 smb_set_ace(aces, psid, parent_aces->type, inherited_flags,
1044 parent_aces->access_req);
1045 nt_size += le16_to_cpu(aces->size);
1047 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1048 flags |= INHERIT_ONLY_ACE;
1050 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) {
1051 psid = &parent_aces->sid;
1054 smb_set_ace(aces, psid, parent_aces->type, flags | inherited_flags,
1055 parent_aces->access_req);
1056 nt_size += le16_to_cpu(aces->size);
1057 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1061 (struct smb_ace *)((char *)parent_aces + le16_to_cpu(parent_aces->size));
1065 struct smb_ntsd *pntsd;
1066 struct smb_acl *pdacl;
1067 struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL;
1068 int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size;
1070 if (parent_pntsd->osidoffset) {
1071 powner_sid = (struct smb_sid *)((char *)parent_pntsd +
1072 le32_to_cpu(parent_pntsd->osidoffset));
1073 powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4);
1075 if (parent_pntsd->gsidoffset) {
1076 pgroup_sid = (struct smb_sid *)((char *)parent_pntsd +
1077 le32_to_cpu(parent_pntsd->gsidoffset));
1078 pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4);
1081 pntsd = kzalloc(sizeof(struct smb_ntsd) + powner_sid_size +
1082 pgroup_sid_size + sizeof(struct smb_acl) +
1083 nt_size, GFP_KERNEL);
1086 goto free_aces_base;
1089 pntsd->revision = cpu_to_le16(1);
1090 pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT);
1091 if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED)
1092 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
1093 pntsd_size = sizeof(struct smb_ntsd);
1094 pntsd->osidoffset = parent_pntsd->osidoffset;
1095 pntsd->gsidoffset = parent_pntsd->gsidoffset;
1096 pntsd->dacloffset = parent_pntsd->dacloffset;
1098 if (pntsd->osidoffset) {
1099 struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd +
1100 le32_to_cpu(pntsd->osidoffset));
1101 memcpy(owner_sid, powner_sid, powner_sid_size);
1102 pntsd_size += powner_sid_size;
1105 if (pntsd->gsidoffset) {
1106 struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd +
1107 le32_to_cpu(pntsd->gsidoffset));
1108 memcpy(group_sid, pgroup_sid, pgroup_sid_size);
1109 pntsd_size += pgroup_sid_size;
1112 if (pntsd->dacloffset) {
1113 struct smb_ace *pace;
1115 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1116 pdacl->revision = cpu_to_le16(2);
1117 pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size);
1118 pdacl->num_aces = cpu_to_le32(ace_cnt);
1119 pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1120 memcpy(pace, aces_base, nt_size);
1121 pntsd_size += sizeof(struct smb_acl) + nt_size;
1124 ksmbd_vfs_set_sd_xattr(conn, user_ns,
1125 path->dentry, pntsd, pntsd_size);
1132 kfree(parent_pntsd);
1136 bool smb_inherit_flags(int flags, bool is_dir)
1139 return (flags & OBJECT_INHERIT_ACE) != 0;
1141 if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE))
1144 if (flags & CONTAINER_INHERIT_ACE)
1149 int smb_check_perm_dacl(struct ksmbd_conn *conn, struct path *path,
1150 __le32 *pdaccess, int uid)
1152 struct user_namespace *user_ns = mnt_user_ns(path->mnt);
1153 struct smb_ntsd *pntsd = NULL;
1154 struct smb_acl *pdacl;
1155 struct posix_acl *posix_acls;
1156 int rc = 0, acl_size;
1158 int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
1159 struct smb_ace *ace;
1161 unsigned int access_bits = 0;
1162 struct smb_ace *others_ace = NULL;
1163 struct posix_acl_entry *pa_entry;
1164 unsigned int sid_type = SIDOWNER;
1167 ksmbd_debug(SMB, "check permission using windows acl\n");
1168 acl_size = ksmbd_vfs_get_sd_xattr(conn, user_ns,
1169 path->dentry, &pntsd);
1170 if (acl_size <= 0 || !pntsd || !pntsd->dacloffset) {
1175 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1176 end_of_acl = ((char *)pntsd) + acl_size;
1177 if (end_of_acl <= (char *)pdacl) {
1182 if (end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size) ||
1183 le16_to_cpu(pdacl->size) < sizeof(struct smb_acl)) {
1188 if (!pdacl->num_aces) {
1189 if (!(le16_to_cpu(pdacl->size) - sizeof(struct smb_acl)) &&
1190 *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) {
1198 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
1199 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1202 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1203 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1204 granted |= le32_to_cpu(ace->access_req);
1205 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1206 if (end_of_acl < (char *)ace)
1210 if (!pdacl->num_aces)
1211 granted = GENERIC_ALL_FLAGS;
1215 sid_type = SIDUNIX_USER;
1216 id_to_sid(uid, sid_type, &sid);
1218 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1219 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1220 if (!compare_sids(&sid, &ace->sid) ||
1221 !compare_sids(&sid_unix_NFS_mode, &ace->sid)) {
1225 if (!compare_sids(&sid_everyone, &ace->sid))
1228 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1229 if (end_of_acl < (char *)ace)
1233 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
1234 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1237 granted |= le32_to_cpu(ace->access_req);
1239 if (!pdacl->num_aces)
1240 granted = GENERIC_ALL_FLAGS;
1243 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
1244 posix_acls = get_acl(d_inode(path->dentry), ACL_TYPE_ACCESS);
1245 if (posix_acls && !found) {
1246 unsigned int id = -1;
1248 pa_entry = posix_acls->a_entries;
1249 for (i = 0; i < posix_acls->a_count; i++, pa_entry++) {
1250 if (pa_entry->e_tag == ACL_USER)
1251 id = posix_acl_uid_translate(user_ns, pa_entry);
1252 else if (pa_entry->e_tag == ACL_GROUP)
1253 id = posix_acl_gid_translate(user_ns, pa_entry);
1258 mode_to_access_flags(pa_entry->e_perm,
1264 goto check_access_bits;
1269 posix_acl_release(posix_acls);
1276 ksmbd_debug(SMB, "Can't find corresponding sid\n");
1282 switch (ace->type) {
1283 case ACCESS_ALLOWED_ACE_TYPE:
1284 access_bits = le32_to_cpu(ace->access_req);
1286 case ACCESS_DENIED_ACE_TYPE:
1287 case ACCESS_DENIED_CALLBACK_ACE_TYPE:
1288 access_bits = le32_to_cpu(~ace->access_req);
1294 ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) {
1295 ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n",
1296 granted, le32_to_cpu(ace->access_req));
1301 *pdaccess = cpu_to_le32(granted);
1307 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
1308 struct path *path, struct smb_ntsd *pntsd, int ntsd_len,
1312 struct smb_fattr fattr = {{0}};
1313 struct inode *inode = d_inode(path->dentry);
1314 struct user_namespace *user_ns = mnt_user_ns(path->mnt);
1315 struct iattr newattrs;
1317 fattr.cf_uid = INVALID_UID;
1318 fattr.cf_gid = INVALID_GID;
1319 fattr.cf_mode = inode->i_mode;
1321 rc = parse_sec_desc(user_ns, pntsd, ntsd_len, &fattr);
1325 newattrs.ia_valid = ATTR_CTIME;
1326 if (!uid_eq(fattr.cf_uid, INVALID_UID)) {
1327 newattrs.ia_valid |= ATTR_UID;
1328 newattrs.ia_uid = fattr.cf_uid;
1330 if (!gid_eq(fattr.cf_gid, INVALID_GID)) {
1331 newattrs.ia_valid |= ATTR_GID;
1332 newattrs.ia_gid = fattr.cf_gid;
1334 newattrs.ia_valid |= ATTR_MODE;
1335 newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
1337 ksmbd_vfs_remove_acl_xattrs(user_ns, path->dentry);
1338 /* Update posix acls */
1339 if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) {
1340 rc = set_posix_acl(user_ns, inode,
1341 ACL_TYPE_ACCESS, fattr.cf_acls);
1344 "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
1346 if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) {
1347 rc = set_posix_acl(user_ns, inode,
1348 ACL_TYPE_DEFAULT, fattr.cf_dacls);
1351 "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n",
1357 rc = notify_change(user_ns, path->dentry, &newattrs, NULL);
1358 inode_unlock(inode);
1362 /* Check it only calling from SD BUFFER context */
1363 if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT))
1366 if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) {
1367 /* Update WinACL in xattr */
1368 ksmbd_vfs_remove_sd_xattrs(user_ns, path->dentry);
1369 ksmbd_vfs_set_sd_xattr(conn, user_ns,
1370 path->dentry, pntsd, ntsd_len);
1374 posix_acl_release(fattr.cf_acls);
1375 posix_acl_release(fattr.cf_dacls);
1376 mark_inode_dirty(inode);
1380 void ksmbd_init_domain(u32 *sub_auth)
1384 memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid));
1385 for (i = 0; i < 3; ++i)
1386 server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]);