fs/ksmbd/smbacl.c

   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  */
  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
 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  */
 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  */
 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
 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
 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
 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 = mapped_kuid_user(user_ns, &init_user_ns, KUIDT_INIT(id));
 279                 if (uid_valid(uid)) {
 280                         fattr->cf_uid = uid;
 281                         rc = 0;
 282                 }
 283         } else {
 284                 kgid_t gid;
 285                 gid_t id;
 286
 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)) {
 290                         fattr->cf_gid = gid;
 291                         rc = 0;
 292                 }
 293         }
 294
 295         return rc;
 296 }
 297
 298 void posix_state_to_acl(struct posix_acl_state *state,
 299                         struct posix_acl_entry *pace)
 300 {
 301         int i;
 302
 303         pace->e_tag = ACL_USER_OBJ;
 304         pace->e_perm = state->owner.allow;
 305         for (i = 0; i < state->users->n; i++) {
 306                 pace++;
 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;
 310         }
 311
 312         pace++;
 313         pace->e_tag = ACL_GROUP_OBJ;
 314         pace->e_perm = state->group.allow;
 315
 316         for (i = 0; i < state->groups->n; i++) {
 317                 pace++;
 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;
 321         }
 322
 323         if (state->users->n || state->groups->n) {
 324                 pace++;
 325                 pace->e_tag = ACL_MASK;
 326                 pace->e_perm = state->mask.allow;
 327         }
 328
 329         pace++;
 330         pace->e_tag = ACL_OTHER;
 331         pace->e_perm = state->other.allow;
 332 }
 333
 334 int init_acl_state(struct posix_acl_state *state, int cnt)
 335 {
 336         int alloc;
 337
 338         memset(state, 0, sizeof(struct posix_acl_state));
 339         /*
 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:
 343          */
 344         alloc = sizeof(struct posix_ace_state_array)
 345                 + cnt * sizeof(struct posix_user_ace_state);
 346         state->users = kzalloc(alloc, GFP_KERNEL);
 347         if (!state->users)
 348                 return -ENOMEM;
 349         state->groups = kzalloc(alloc, GFP_KERNEL);
 350         if (!state->groups) {
 351                 kfree(state->users);
 352                 return -ENOMEM;
 353         }
 354         return 0;
 355 }
 356
 357 void free_acl_state(struct posix_acl_state *state)
 358 {
 359         kfree(state->users);
 360         kfree(state->groups);
 361 }
 362
 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)
 367 {
 368         int i, ret;
 369         int num_aces = 0;
 370         unsigned int acl_size;
 371         char *acl_base;
 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;
 377
 378         if (!pdacl)
 379                 return;
 380
 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");
 385                 return;
 386         }
 387
 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));
 391
 392         acl_base = (char *)pdacl;
 393         acl_size = sizeof(struct smb_acl);
 394
 395         num_aces = le32_to_cpu(pdacl->num_aces);
 396         if (num_aces <= 0)
 397                 return;
 398
 399         if (num_aces > ULONG_MAX / sizeof(struct smb_ace *))
 400                 return;
 401
 402         ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL);
 403         if (!ppace)
 404                 return;
 405
 406         ret = init_acl_state(&acl_state, num_aces);
 407         if (ret)
 408                 return;
 409         ret = init_acl_state(&default_acl_state, num_aces);
 410         if (ret) {
 411                 free_acl_state(&acl_state);
 412                 return;
 413         }
 414
 415         /*
 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
 419          */
 420         for (i = 0; i < num_aces; ++i) {
 421                 if (end_of_acl - acl_base < acl_size)
 422                         break;
 423
 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);
 428
 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))
 435                         break;
 436
 437                 acl_size = le16_to_cpu(ppace[i]->size);
 438                 ppace[i]->access_req =
 439                         smb_map_generic_desired_access(ppace[i]->access_req);
 440
 441                 if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) {
 442                         fattr->cf_mode =
 443                                 le32_to_cpu(ppace[i]->sid.sub_auth[2]);
 444                         break;
 445                 } else if (!compare_sids(&ppace[i]->sid, pownersid)) {
 446                         acl_mode = access_flags_to_mode(fattr,
 447                                                         ppace[i]->access_req,
 448                                                         ppace[i]->type);
 449                         acl_mode &= 0700;
 450
 451                         if (!owner_found) {
 452                                 mode &= ~(0700);
 453                                 mode |= acl_mode;
 454                         }
 455                         owner_found = true;
 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,
 461                                                         ppace[i]->type);
 462                         acl_mode &= 0070;
 463                         if (!group_found) {
 464                                 mode &= ~(0070);
 465                                 mode |= acl_mode;
 466                         }
 467                         group_found = true;
 468                 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) {
 469                         acl_mode = access_flags_to_mode(fattr,
 470                                                         ppace[i]->access_req,
 471                                                         ppace[i]->type);
 472                         acl_mode &= 0007;
 473                         if (!others_found) {
 474                                 mode &= ~(0007);
 475                                 mode |= acl_mode;
 476                         }
 477                         others_found = true;
 478                 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) {
 479                         continue;
 480                 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) {
 481                         continue;
 482                 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) {
 483                         continue;
 484                 } else {
 485                         struct smb_fattr temp_fattr;
 486
 487                         acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
 488                                                         ppace[i]->type);
 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",
 493                                        __func__, ret);
 494                                 continue;
 495                         }
 496
 497                         acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
 498                         acl_state.users->aces[acl_state.users->n].uid =
 499                                 temp_fattr.cf_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 =
 504                                 temp_fattr.cf_uid;
 505                         default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
 506                                 ((acl_mode & 0700) >> 6) | 0004;
 507                 }
 508         }
 509         kfree(ppace);
 510
 511         if (owner_found) {
 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 =
 519                         fattr->cf_uid;
 520                 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
 521                         ((mode & 0700) >> 6) | 0004;
 522         }
 523
 524         if (group_found) {
 525                 acl_state.group.allow = (mode & 0070) >> 3;
 526                 acl_state.groups->aces[acl_state.groups->n].gid =
 527                         fattr->cf_gid;
 528                 acl_state.groups->aces[acl_state.groups->n++].perms.allow =
 529                         (mode & 0070) >> 3;
 530                 default_acl_state.group.allow = (mode & 0070) >> 3;
 531                 default_acl_state.groups->aces[default_acl_state.groups->n].gid =
 532                         fattr->cf_gid;
 533                 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow =
 534                         (mode & 0070) >> 3;
 535         }
 536
 537         if (others_found) {
 538                 fattr->cf_mode &= ~(0007);
 539                 fattr->cf_mode |= mode & 0007;
 540
 541                 acl_state.other.allow = mode & 0007;
 542                 default_acl_state.other.allow = mode & 0007;
 543         }
 544
 545         if (acl_state.users->n || acl_state.groups->n) {
 546                 acl_state.mask.allow = 0x07;
 547
 548                 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
 549                         fattr->cf_acls =
 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);
 555                         }
 556                 }
 557         }
 558
 559         if (default_acl_state.users->n || default_acl_state.groups->n) {
 560                 default_acl_state.mask.allow = 0x07;
 561
 562                 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
 563                         fattr->cf_dacls =
 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);
 569                         }
 570                 }
 571         }
 572         free_acl_state(&acl_state);
 573         free_acl_state(&default_acl_state);
 574 }
 575
 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)
 580 {
 581         struct posix_acl_entry *pace;
 582         struct smb_sid *sid;
 583         struct smb_ace *ntace;
 584         int i, j;
 585
 586         if (!fattr->cf_acls)
 587                 goto posix_default_acl;
 588
 589         pace = fattr->cf_acls->a_entries;
 590         for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) {
 591                 int flags = 0;
 592
 593                 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 594                 if (!sid)
 595                         break;
 596
 597                 if (pace->e_tag == ACL_USER) {
 598                         uid_t uid;
 599                         unsigned int sid_type = SIDOWNER;
 600
 601                         uid = posix_acl_uid_translate(user_ns, pace);
 602                         if (!uid)
 603                                 sid_type = SIDUNIX_USER;
 604                         id_to_sid(uid, sid_type, sid);
 605                 } else if (pace->e_tag == ACL_GROUP) {
 606                         gid_t gid;
 607
 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);
 612                 } else {
 613                         kfree(sid);
 614                         continue;
 615                 }
 616                 ntace = pndace;
 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])
 620                                 goto pass_same_sid;
 621                         ntace = (struct smb_ace *)((char *)ntace +
 622                                         le16_to_cpu(ntace->size));
 623                 }
 624
 625                 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER)
 626                         flags = 0x03;
 627
 628                 ntace = (struct smb_ace *)((char *)pndace + *size);
 629                 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags,
 630                                 pace->e_perm, 0777);
 631                 (*num_aces)++;
 632                 if (pace->e_tag == ACL_USER)
 633                         ntace->access_req |=
 634                                 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
 635
 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);
 641                         (*num_aces)++;
 642                         if (pace->e_tag == ACL_USER)
 643                                 ntace->access_req |=
 644                                         FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
 645                 }
 646
 647 pass_same_sid:
 648                 kfree(sid);
 649         }
 650
 651         if (nt_aces_num)
 652                 return;
 653
 654 posix_default_acl:
 655         if (!fattr->cf_dacls)
 656                 return;
 657
 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);
 661                 if (!sid)
 662                         break;
 663
 664                 if (pace->e_tag == ACL_USER) {
 665                         uid_t uid;
 666
 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) {
 670                         gid_t gid;
 671
 672                         gid = posix_acl_gid_translate(user_ns, pace);
 673                         id_to_sid(gid, SIDCREATOR_GROUP, sid);
 674                 } else {
 675                         kfree(sid);
 676                         continue;
 677                 }
 678
 679                 ntace = (struct smb_ace *)((char *)pndace + *size);
 680                 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b,
 681                                 pace->e_perm, 0777);
 682                 (*num_aces)++;
 683                 if (pace->e_tag == ACL_USER)
 684                         ntace->access_req |=
 685                                 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
 686                 kfree(sid);
 687         }
 688 }
 689
 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)
 696 {
 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;
 700         int i;
 701
 702         pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
 703         if (nt_num_aces) {
 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));
 709                         num_aces++;
 710                 }
 711         }
 712
 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);
 717 }
 718
 719 static void set_mode_dacl(struct user_namespace *user_ns,
 720                           struct smb_acl *pndacl, struct smb_fattr *fattr)
 721 {
 722         struct smb_ace *pace, *pndace;
 723         u32 num_aces = 0;
 724         u16 size = 0, ace_size = 0;
 725         uid_t uid;
 726         const struct smb_sid *sid;
 727
 728         pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
 729
 730         if (fattr->cf_acls) {
 731                 set_posix_acl_entries_dacl(user_ns, pndace, fattr,
 732                                            &num_aces, &size, num_aces);
 733                 goto out;
 734         }
 735
 736         /* owner RID */
 737         uid = from_kuid(&init_user_ns, fattr->cf_uid);
 738         if (uid)
 739                 sid = &server_conf.domain_sid;
 740         else
 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);
 748
 749         /* Group RID */
 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);
 757         num_aces = 3;
 758
 759         if (S_ISDIR(fattr->cf_mode)) {
 760                 pace = (struct smb_ace *)((char *)pndace + size);
 761
 762                 /* creator owner */
 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);
 766
 767                 /* creator group */
 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);
 771                 num_aces = 5;
 772         }
 773
 774         /* other */
 775         size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0,
 776                                  fattr->cf_mode, 0007);
 777
 778 out:
 779         pndacl->num_aces = cpu_to_le32(num_aces);
 780         pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
 781 }
 782
 783 static int parse_sid(struct smb_sid *psid, char *end_of_acl)
 784 {
 785         /*
 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
 788          */
 789         if (end_of_acl < (char *)psid + 8) {
 790                 pr_err("ACL too small to parse SID %p\n", psid);
 791                 return -EINVAL;
 792         }
 793
 794         return 0;
 795 }
 796
 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)
 800 {
 801         int rc = 0;
 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;
 805         __u32 dacloffset;
 806         int pntsd_type;
 807
 808         if (!pntsd)
 809                 return -EIO;
 810
 811         if (acl_len < sizeof(struct smb_ntsd))
 812                 return -EINVAL;
 813
 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);
 820         ksmbd_debug(SMB,
 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);
 825
 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");
 829                 return rc;
 830         }
 831
 832         pntsd->type = cpu_to_le16(DACL_PRESENT);
 833
 834         if (pntsd->osidoffset) {
 835                 rc = parse_sid(owner_sid_ptr, end_of_acl);
 836                 if (rc) {
 837                         pr_err("%s: Error %d parsing Owner SID\n", __func__, rc);
 838                         return rc;
 839                 }
 840
 841                 rc = sid_to_id(user_ns, owner_sid_ptr, SIDOWNER, fattr);
 842                 if (rc) {
 843                         pr_err("%s: Error %d mapping Owner SID to uid\n",
 844                                __func__, rc);
 845                         owner_sid_ptr = NULL;
 846                 }
 847         }
 848
 849         if (pntsd->gsidoffset) {
 850                 rc = parse_sid(group_sid_ptr, end_of_acl);
 851                 if (rc) {
 852                         pr_err("%s: Error %d mapping Owner SID to gid\n",
 853                                __func__, rc);
 854                         return rc;
 855                 }
 856                 rc = sid_to_id(user_ns, group_sid_ptr, SIDUNIX_GROUP, fattr);
 857                 if (rc) {
 858                         pr_err("%s: Error %d mapping Group SID to gid\n",
 859                                __func__, rc);
 860                         group_sid_ptr = NULL;
 861                 }
 862         }
 863
 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);
 869
 870         if (dacloffset) {
 871                 parse_dacl(user_ns, dacl_ptr, end_of_acl,
 872                            owner_sid_ptr, group_sid_ptr, fattr);
 873         }
 874
 875         return 0;
 876 }
 877
 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)
 883 {
 884         int rc = 0;
 885         __u32 offset;
 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 */
 889         uid_t uid;
 890         gid_t gid;
 891         unsigned int sid_type = SIDOWNER;
 892
 893         nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 894         if (!nowner_sid_ptr)
 895                 return -ENOMEM;
 896
 897         uid = from_kuid(&init_user_ns, fattr->cf_uid);
 898         if (!uid)
 899                 sid_type = SIDUNIX_USER;
 900         id_to_sid(uid, sid_type, nowner_sid_ptr);
 901
 902         ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 903         if (!ngroup_sid_ptr) {
 904                 kfree(nowner_sid_ptr);
 905                 return -ENOMEM;
 906         }
 907
 908         gid = from_kgid(&init_user_ns, fattr->cf_gid);
 909         id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr);
 910
 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);
 915         if (ppntsd)
 916                 pntsd->type |= ppntsd->type;
 917
 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);
 923         }
 924
 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);
 930         }
 931
 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;
 938
 939                 if (!ppntsd) {
 940                         set_mode_dacl(user_ns, dacl_ptr, fattr);
 941                 } else if (!ppntsd->dacloffset) {
 942                         goto out;
 943                 } else {
 944                         struct smb_acl *ppdacl_ptr;
 945
 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);
 950                 }
 951                 pntsd->dacloffset = cpu_to_le32(offset);
 952                 offset += le16_to_cpu(dacl_ptr->size);
 953         }
 954
 955 out:
 956         kfree(nowner_sid_ptr);
 957         kfree(ngroup_sid_ptr);
 958         *secdesclen = offset;
 959         return rc;
 960 }
 961
 962 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type,
 963                         u8 flags, __le32 access_req)
 964 {
 965         ace->type = type;
 966         ace->flags = flags;
 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));
 970 }
 971
 972 int smb_inherit_dacl(struct ksmbd_conn *conn,
 973                      struct path *path,
 974                      unsigned int uid, unsigned int gid)
 975 {
 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;
 985         char *aces_base;
 986         bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
 987
 988         acl_len = ksmbd_vfs_get_sd_xattr(conn, user_ns,
 989                                          parent, &parent_pntsd);
 990         if (acl_len <= 0)
 991                 return -ENOENT;
 992         dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
 993         if (!dacloffset) {
 994                 rc = -EINVAL;
 995                 goto free_parent_pntsd;
 996         }
 997
 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);
1001
1002         aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL);
1003         if (!aces_base) {
1004                 rc = -ENOMEM;
1005                 goto free_parent_pntsd;
1006         }
1007
1008         aces = (struct smb_ace *)aces_base;
1009         parent_aces = (struct smb_ace *)((char *)parent_pdacl +
1010                         sizeof(struct smb_acl));
1011
1012         if (pntsd_type & DACL_AUTO_INHERITED)
1013                 inherited_flags = INHERITED_ACE;
1014
1015         for (i = 0; i < num_aces; i++) {
1016                 flags = parent_aces->flags;
1017                 if (!smb_inherit_flags(flags, is_dir))
1018                         goto pass;
1019                 if (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)
1024                                 flags = 0;
1025                 } else {
1026                         flags = 0;
1027                 }
1028
1029                 if (!compare_sids(&creator_owner, &parent_aces->sid)) {
1030                         creator = &creator_owner;
1031                         id_to_sid(uid, SIDOWNER, &owner_sid);
1032                         psid = &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);
1036                         psid = &group_sid;
1037                 } else {
1038                         creator = NULL;
1039                         psid = &parent_aces->sid;
1040                 }
1041
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);
1046                         ace_cnt++;
1047                         aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1048                         flags |= INHERIT_ONLY_ACE;
1049                         psid = creator;
1050                 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) {
1051                         psid = &parent_aces->sid;
1052                 }
1053
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));
1058                 ace_cnt++;
1059 pass:
1060                 parent_aces =
1061                         (struct smb_ace *)((char *)parent_aces + le16_to_cpu(parent_aces->size));
1062         }
1063
1064         if (nt_size > 0) {
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;
1069
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);
1074                 }
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);
1079                 }
1080
1081                 pntsd = kzalloc(sizeof(struct smb_ntsd) + powner_sid_size +
1082                                 pgroup_sid_size + sizeof(struct smb_acl) +
1083                                 nt_size, GFP_KERNEL);
1084                 if (!pntsd) {
1085                         rc = -ENOMEM;
1086                         goto free_aces_base;
1087                 }
1088
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;
1097
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;
1103                 }
1104
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;
1110                 }
1111
1112                 if (pntsd->dacloffset) {
1113                         struct smb_ace *pace;
1114
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;
1122                 }
1123
1124                 ksmbd_vfs_set_sd_xattr(conn, user_ns,
1125                                        path->dentry, pntsd, pntsd_size);
1126                 kfree(pntsd);
1127         }
1128
1129 free_aces_base:
1130         kfree(aces_base);
1131 free_parent_pntsd:
1132         kfree(parent_pntsd);
1133         return rc;
1134 }
1135
1136 bool smb_inherit_flags(int flags, bool is_dir)
1137 {
1138         if (!is_dir)
1139                 return (flags & OBJECT_INHERIT_ACE) != 0;
1140
1141         if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE))
1142                 return true;
1143
1144         if (flags & CONTAINER_INHERIT_ACE)
1145                 return true;
1146         return false;
1147 }
1148
1149 int smb_check_perm_dacl(struct ksmbd_conn *conn, struct path *path,
1150                         __le32 *pdaccess, int uid)
1151 {
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;
1157         struct smb_sid sid;
1158         int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
1159         struct smb_ace *ace;
1160         int i, found = 0;
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;
1165         char *end_of_acl;
1166
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) {
1171                 kfree(pntsd);
1172                 return 0;
1173         }
1174
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) {
1178                 kfree(pntsd);
1179                 return 0;
1180         }
1181
1182         if (end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size) ||
1183             le16_to_cpu(pdacl->size) < sizeof(struct smb_acl)) {
1184                 kfree(pntsd);
1185                 return 0;
1186         }
1187
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)) {
1191                         rc = -EACCES;
1192                         goto err_out;
1193                 }
1194                 kfree(pntsd);
1195                 return 0;
1196         }
1197
1198         if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
1199                 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1200                         DELETE;
1201
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)
1207                                 goto err_out;
1208                 }
1209
1210                 if (!pdacl->num_aces)
1211                         granted = GENERIC_ALL_FLAGS;
1212         }
1213
1214         if (!uid)
1215                 sid_type = SIDUNIX_USER;
1216         id_to_sid(uid, sid_type, &sid);
1217
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)) {
1222                         found = 1;
1223                         break;
1224                 }
1225                 if (!compare_sids(&sid_everyone, &ace->sid))
1226                         others_ace = ace;
1227
1228                 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1229                 if (end_of_acl < (char *)ace)
1230                         goto err_out;
1231         }
1232
1233         if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
1234                 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1235                         DELETE;
1236
1237                 granted |= le32_to_cpu(ace->access_req);
1238
1239                 if (!pdacl->num_aces)
1240                         granted = GENERIC_ALL_FLAGS;
1241         }
1242
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;
1247
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);
1254                                 else
1255                                         continue;
1256
1257                                 if (id == uid) {
1258                                         mode_to_access_flags(pa_entry->e_perm,
1259                                                              0777,
1260                                                              &access_bits);
1261                                         if (!access_bits)
1262                                                 access_bits =
1263                                                         SET_MINIMUM_RIGHTS;
1264                                         goto check_access_bits;
1265                                 }
1266                         }
1267                 }
1268                 if (posix_acls)
1269                         posix_acl_release(posix_acls);
1270         }
1271
1272         if (!found) {
1273                 if (others_ace) {
1274                         ace = others_ace;
1275                 } else {
1276                         ksmbd_debug(SMB, "Can't find corresponding sid\n");
1277                         rc = -EACCES;
1278                         goto err_out;
1279                 }
1280         }
1281
1282         switch (ace->type) {
1283         case ACCESS_ALLOWED_ACE_TYPE:
1284                 access_bits = le32_to_cpu(ace->access_req);
1285                 break;
1286         case ACCESS_DENIED_ACE_TYPE:
1287         case ACCESS_DENIED_CALLBACK_ACE_TYPE:
1288                 access_bits = le32_to_cpu(~ace->access_req);
1289                 break;
1290         }
1291
1292 check_access_bits:
1293         if (granted &
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));
1297                 rc = -EACCES;
1298                 goto err_out;
1299         }
1300
1301         *pdaccess = cpu_to_le32(granted);
1302 err_out:
1303         kfree(pntsd);
1304         return rc;
1305 }
1306
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,
1309                  bool type_check)
1310 {
1311         int rc;
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;
1316
1317         fattr.cf_uid = INVALID_UID;
1318         fattr.cf_gid = INVALID_GID;
1319         fattr.cf_mode = inode->i_mode;
1320
1321         rc = parse_sec_desc(user_ns, pntsd, ntsd_len, &fattr);
1322         if (rc)
1323                 goto out;
1324
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;
1329         }
1330         if (!gid_eq(fattr.cf_gid, INVALID_GID)) {
1331                 newattrs.ia_valid |= ATTR_GID;
1332                 newattrs.ia_gid = fattr.cf_gid;
1333         }
1334         newattrs.ia_valid |= ATTR_MODE;
1335         newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
1336
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);
1342                 if (rc < 0)
1343                         ksmbd_debug(SMB,
1344                                     "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
1345                                     rc);
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);
1349                         if (rc)
1350                                 ksmbd_debug(SMB,
1351                                             "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n",
1352                                             rc);
1353                 }
1354         }
1355
1356         inode_lock(inode);
1357         rc = notify_change(user_ns, path->dentry, &newattrs, NULL);
1358         inode_unlock(inode);
1359         if (rc)
1360                 goto out;
1361
1362         /* Check it only calling from SD BUFFER context */
1363         if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT))
1364                 goto out;
1365
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);
1371         }
1372
1373 out:
1374         posix_acl_release(fattr.cf_acls);
1375         posix_acl_release(fattr.cf_dacls);
1376         mark_inode_dirty(inode);
1377         return rc;
1378 }
1379
1380 void ksmbd_init_domain(u32 *sub_auth)
1381 {
1382         int i;
1383
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]);
1387 }