smb/server/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 = min(num_sat, num_saw);
 101         if (num_subauth) {
 102                 for (i = 0; i < num_subauth; ++i) {
 103                         if (ctsid->sub_auth[i] != cwsid->sub_auth[i]) {
 104                                 if (le32_to_cpu(ctsid->sub_auth[i]) >
 105                                     le32_to_cpu(cwsid->sub_auth[i]))
 106                                         return 1;
 107                                 else
 108                                         return -1;
 109                         }
 110                 }
 111         }
 112
 113         return 0; /* sids compare/match */
 114 }
 115
 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 = KUIDT_INIT(id);
 279                 uid = from_vfsuid(user_ns, &init_user_ns, VFSUIDT_INIT(uid));
 280                 if (uid_valid(uid)) {
 281                         fattr->cf_uid = uid;
 282                         rc = 0;
 283                 }
 284         } else {
 285                 kgid_t gid;
 286                 gid_t id;
 287
 288                 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
 289                 gid = KGIDT_INIT(id);
 290                 gid = from_vfsgid(user_ns, &init_user_ns, VFSGIDT_INIT(gid));
 291                 if (gid_valid(gid)) {
 292                         fattr->cf_gid = gid;
 293                         rc = 0;
 294                 }
 295         }
 296
 297         return rc;
 298 }
 299
 300 void posix_state_to_acl(struct posix_acl_state *state,
 301                         struct posix_acl_entry *pace)
 302 {
 303         int i;
 304
 305         pace->e_tag = ACL_USER_OBJ;
 306         pace->e_perm = state->owner.allow;
 307         for (i = 0; i < state->users->n; i++) {
 308                 pace++;
 309                 pace->e_tag = ACL_USER;
 310                 pace->e_uid = state->users->aces[i].uid;
 311                 pace->e_perm = state->users->aces[i].perms.allow;
 312         }
 313
 314         pace++;
 315         pace->e_tag = ACL_GROUP_OBJ;
 316         pace->e_perm = state->group.allow;
 317
 318         for (i = 0; i < state->groups->n; i++) {
 319                 pace++;
 320                 pace->e_tag = ACL_GROUP;
 321                 pace->e_gid = state->groups->aces[i].gid;
 322                 pace->e_perm = state->groups->aces[i].perms.allow;
 323         }
 324
 325         if (state->users->n || state->groups->n) {
 326                 pace++;
 327                 pace->e_tag = ACL_MASK;
 328                 pace->e_perm = state->mask.allow;
 329         }
 330
 331         pace++;
 332         pace->e_tag = ACL_OTHER;
 333         pace->e_perm = state->other.allow;
 334 }
 335
 336 int init_acl_state(struct posix_acl_state *state, int cnt)
 337 {
 338         int alloc;
 339
 340         memset(state, 0, sizeof(struct posix_acl_state));
 341         /*
 342          * In the worst case, each individual acl could be for a distinct
 343          * named user or group, but we don't know which, so we allocate
 344          * enough space for either:
 345          */
 346         alloc = sizeof(struct posix_ace_state_array)
 347                 + cnt * sizeof(struct posix_user_ace_state);
 348         state->users = kzalloc(alloc, GFP_KERNEL);
 349         if (!state->users)
 350                 return -ENOMEM;
 351         state->groups = kzalloc(alloc, GFP_KERNEL);
 352         if (!state->groups) {
 353                 kfree(state->users);
 354                 return -ENOMEM;
 355         }
 356         return 0;
 357 }
 358
 359 void free_acl_state(struct posix_acl_state *state)
 360 {
 361         kfree(state->users);
 362         kfree(state->groups);
 363 }
 364
 365 static void parse_dacl(struct user_namespace *user_ns,
 366                        struct smb_acl *pdacl, char *end_of_acl,
 367                        struct smb_sid *pownersid, struct smb_sid *pgrpsid,
 368                        struct smb_fattr *fattr)
 369 {
 370         int i, ret;
 371         int num_aces = 0;
 372         unsigned int acl_size;
 373         char *acl_base;
 374         struct smb_ace **ppace;
 375         struct posix_acl_entry *cf_pace, *cf_pdace;
 376         struct posix_acl_state acl_state, default_acl_state;
 377         umode_t mode = 0, acl_mode;
 378         bool owner_found = false, group_found = false, others_found = false;
 379
 380         if (!pdacl)
 381                 return;
 382
 383         /* validate that we do not go past end of acl */
 384         if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) ||
 385             end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) {
 386                 pr_err("ACL too small to parse DACL\n");
 387                 return;
 388         }
 389
 390         ksmbd_debug(SMB, "DACL revision %d size %d num aces %d\n",
 391                     le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size),
 392                     le32_to_cpu(pdacl->num_aces));
 393
 394         acl_base = (char *)pdacl;
 395         acl_size = sizeof(struct smb_acl);
 396
 397         num_aces = le32_to_cpu(pdacl->num_aces);
 398         if (num_aces <= 0)
 399                 return;
 400
 401         if (num_aces > ULONG_MAX / sizeof(struct smb_ace *))
 402                 return;
 403
 404         ret = init_acl_state(&acl_state, num_aces);
 405         if (ret)
 406                 return;
 407         ret = init_acl_state(&default_acl_state, num_aces);
 408         if (ret) {
 409                 free_acl_state(&acl_state);
 410                 return;
 411         }
 412
 413         ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL);
 414         if (!ppace) {
 415                 free_acl_state(&default_acl_state);
 416                 free_acl_state(&acl_state);
 417                 return;
 418         }
 419
 420         /*
 421          * reset rwx permissions for user/group/other.
 422          * Also, if num_aces is 0 i.e. DACL has no ACEs,
 423          * user/group/other have no permissions
 424          */
 425         for (i = 0; i < num_aces; ++i) {
 426                 if (end_of_acl - acl_base < acl_size)
 427                         break;
 428
 429                 ppace[i] = (struct smb_ace *)(acl_base + acl_size);
 430                 acl_base = (char *)ppace[i];
 431                 acl_size = offsetof(struct smb_ace, sid) +
 432                         offsetof(struct smb_sid, sub_auth);
 433
 434                 if (end_of_acl - acl_base < acl_size ||
 435                     ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES ||
 436                     (end_of_acl - acl_base <
 437                      acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) ||
 438                     (le16_to_cpu(ppace[i]->size) <
 439                      acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth))
 440                         break;
 441
 442                 acl_size = le16_to_cpu(ppace[i]->size);
 443                 ppace[i]->access_req =
 444                         smb_map_generic_desired_access(ppace[i]->access_req);
 445
 446                 if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) {
 447                         fattr->cf_mode =
 448                                 le32_to_cpu(ppace[i]->sid.sub_auth[2]);
 449                         break;
 450                 } else if (!compare_sids(&ppace[i]->sid, pownersid)) {
 451                         acl_mode = access_flags_to_mode(fattr,
 452                                                         ppace[i]->access_req,
 453                                                         ppace[i]->type);
 454                         acl_mode &= 0700;
 455
 456                         if (!owner_found) {
 457                                 mode &= ~(0700);
 458                                 mode |= acl_mode;
 459                         }
 460                         owner_found = true;
 461                 } else if (!compare_sids(&ppace[i]->sid, pgrpsid) ||
 462                            ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] ==
 463                             DOMAIN_USER_RID_LE) {
 464                         acl_mode = access_flags_to_mode(fattr,
 465                                                         ppace[i]->access_req,
 466                                                         ppace[i]->type);
 467                         acl_mode &= 0070;
 468                         if (!group_found) {
 469                                 mode &= ~(0070);
 470                                 mode |= acl_mode;
 471                         }
 472                         group_found = true;
 473                 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) {
 474                         acl_mode = access_flags_to_mode(fattr,
 475                                                         ppace[i]->access_req,
 476                                                         ppace[i]->type);
 477                         acl_mode &= 0007;
 478                         if (!others_found) {
 479                                 mode &= ~(0007);
 480                                 mode |= acl_mode;
 481                         }
 482                         others_found = true;
 483                 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) {
 484                         continue;
 485                 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) {
 486                         continue;
 487                 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) {
 488                         continue;
 489                 } else {
 490                         struct smb_fattr temp_fattr;
 491
 492                         acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
 493                                                         ppace[i]->type);
 494                         temp_fattr.cf_uid = INVALID_UID;
 495                         ret = sid_to_id(user_ns, &ppace[i]->sid, SIDOWNER, &temp_fattr);
 496                         if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) {
 497                                 pr_err("%s: Error %d mapping Owner SID to uid\n",
 498                                        __func__, ret);
 499                                 continue;
 500                         }
 501
 502                         acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
 503                         acl_state.users->aces[acl_state.users->n].uid =
 504                                 temp_fattr.cf_uid;
 505                         acl_state.users->aces[acl_state.users->n++].perms.allow =
 506                                 ((acl_mode & 0700) >> 6) | 0004;
 507                         default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
 508                         default_acl_state.users->aces[default_acl_state.users->n].uid =
 509                                 temp_fattr.cf_uid;
 510                         default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
 511                                 ((acl_mode & 0700) >> 6) | 0004;
 512                 }
 513         }
 514         kfree(ppace);
 515
 516         if (owner_found) {
 517                 /* The owner must be set to at least read-only. */
 518                 acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
 519                 acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid;
 520                 acl_state.users->aces[acl_state.users->n++].perms.allow =
 521                         ((mode & 0700) >> 6) | 0004;
 522                 default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
 523                 default_acl_state.users->aces[default_acl_state.users->n].uid =
 524                         fattr->cf_uid;
 525                 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
 526                         ((mode & 0700) >> 6) | 0004;
 527         }
 528
 529         if (group_found) {
 530                 acl_state.group.allow = (mode & 0070) >> 3;
 531                 acl_state.groups->aces[acl_state.groups->n].gid =
 532                         fattr->cf_gid;
 533                 acl_state.groups->aces[acl_state.groups->n++].perms.allow =
 534                         (mode & 0070) >> 3;
 535                 default_acl_state.group.allow = (mode & 0070) >> 3;
 536                 default_acl_state.groups->aces[default_acl_state.groups->n].gid =
 537                         fattr->cf_gid;
 538                 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow =
 539                         (mode & 0070) >> 3;
 540         }
 541
 542         if (others_found) {
 543                 fattr->cf_mode &= ~(0007);
 544                 fattr->cf_mode |= mode & 0007;
 545
 546                 acl_state.other.allow = mode & 0007;
 547                 default_acl_state.other.allow = mode & 0007;
 548         }
 549
 550         if (acl_state.users->n || acl_state.groups->n) {
 551                 acl_state.mask.allow = 0x07;
 552
 553                 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
 554                         fattr->cf_acls =
 555                                 posix_acl_alloc(acl_state.users->n +
 556                                         acl_state.groups->n + 4, GFP_KERNEL);
 557                         if (fattr->cf_acls) {
 558                                 cf_pace = fattr->cf_acls->a_entries;
 559                                 posix_state_to_acl(&acl_state, cf_pace);
 560                         }
 561                 }
 562         }
 563
 564         if (default_acl_state.users->n || default_acl_state.groups->n) {
 565                 default_acl_state.mask.allow = 0x07;
 566
 567                 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
 568                         fattr->cf_dacls =
 569                                 posix_acl_alloc(default_acl_state.users->n +
 570                                 default_acl_state.groups->n + 4, GFP_KERNEL);
 571                         if (fattr->cf_dacls) {
 572                                 cf_pdace = fattr->cf_dacls->a_entries;
 573                                 posix_state_to_acl(&default_acl_state, cf_pdace);
 574                         }
 575                 }
 576         }
 577         free_acl_state(&acl_state);
 578         free_acl_state(&default_acl_state);
 579 }
 580
 581 static void set_posix_acl_entries_dacl(struct user_namespace *user_ns,
 582                                        struct smb_ace *pndace,
 583                                        struct smb_fattr *fattr, u32 *num_aces,
 584                                        u16 *size, u32 nt_aces_num)
 585 {
 586         struct posix_acl_entry *pace;
 587         struct smb_sid *sid;
 588         struct smb_ace *ntace;
 589         int i, j;
 590
 591         if (!fattr->cf_acls)
 592                 goto posix_default_acl;
 593
 594         pace = fattr->cf_acls->a_entries;
 595         for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) {
 596                 int flags = 0;
 597
 598                 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 599                 if (!sid)
 600                         break;
 601
 602                 if (pace->e_tag == ACL_USER) {
 603                         uid_t uid;
 604                         unsigned int sid_type = SIDOWNER;
 605
 606                         uid = posix_acl_uid_translate(user_ns, pace);
 607                         if (!uid)
 608                                 sid_type = SIDUNIX_USER;
 609                         id_to_sid(uid, sid_type, sid);
 610                 } else if (pace->e_tag == ACL_GROUP) {
 611                         gid_t gid;
 612
 613                         gid = posix_acl_gid_translate(user_ns, pace);
 614                         id_to_sid(gid, SIDUNIX_GROUP, sid);
 615                 } else if (pace->e_tag == ACL_OTHER && !nt_aces_num) {
 616                         smb_copy_sid(sid, &sid_everyone);
 617                 } else {
 618                         kfree(sid);
 619                         continue;
 620                 }
 621                 ntace = pndace;
 622                 for (j = 0; j < nt_aces_num; j++) {
 623                         if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] ==
 624                                         sid->sub_auth[sid->num_subauth - 1])
 625                                 goto pass_same_sid;
 626                         ntace = (struct smb_ace *)((char *)ntace +
 627                                         le16_to_cpu(ntace->size));
 628                 }
 629
 630                 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER)
 631                         flags = 0x03;
 632
 633                 ntace = (struct smb_ace *)((char *)pndace + *size);
 634                 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags,
 635                                 pace->e_perm, 0777);
 636                 (*num_aces)++;
 637                 if (pace->e_tag == ACL_USER)
 638                         ntace->access_req |=
 639                                 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
 640
 641                 if (S_ISDIR(fattr->cf_mode) &&
 642                     (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) {
 643                         ntace = (struct smb_ace *)((char *)pndace + *size);
 644                         *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED,
 645                                         0x03, pace->e_perm, 0777);
 646                         (*num_aces)++;
 647                         if (pace->e_tag == ACL_USER)
 648                                 ntace->access_req |=
 649                                         FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
 650                 }
 651
 652 pass_same_sid:
 653                 kfree(sid);
 654         }
 655
 656         if (nt_aces_num)
 657                 return;
 658
 659 posix_default_acl:
 660         if (!fattr->cf_dacls)
 661                 return;
 662
 663         pace = fattr->cf_dacls->a_entries;
 664         for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) {
 665                 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 666                 if (!sid)
 667                         break;
 668
 669                 if (pace->e_tag == ACL_USER) {
 670                         uid_t uid;
 671
 672                         uid = posix_acl_uid_translate(user_ns, pace);
 673                         id_to_sid(uid, SIDCREATOR_OWNER, sid);
 674                 } else if (pace->e_tag == ACL_GROUP) {
 675                         gid_t gid;
 676
 677                         gid = posix_acl_gid_translate(user_ns, pace);
 678                         id_to_sid(gid, SIDCREATOR_GROUP, sid);
 679                 } else {
 680                         kfree(sid);
 681                         continue;
 682                 }
 683
 684                 ntace = (struct smb_ace *)((char *)pndace + *size);
 685                 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b,
 686                                 pace->e_perm, 0777);
 687                 (*num_aces)++;
 688                 if (pace->e_tag == ACL_USER)
 689                         ntace->access_req |=
 690                                 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
 691                 kfree(sid);
 692         }
 693 }
 694
 695 static void set_ntacl_dacl(struct user_namespace *user_ns,
 696                            struct smb_acl *pndacl,
 697                            struct smb_acl *nt_dacl,
 698                            unsigned int aces_size,
 699                            const struct smb_sid *pownersid,
 700                            const struct smb_sid *pgrpsid,
 701                            struct smb_fattr *fattr)
 702 {
 703         struct smb_ace *ntace, *pndace;
 704         int nt_num_aces = le32_to_cpu(nt_dacl->num_aces), num_aces = 0;
 705         unsigned short size = 0;
 706         int i;
 707
 708         pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
 709         if (nt_num_aces) {
 710                 ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl));
 711                 for (i = 0; i < nt_num_aces; i++) {
 712                         unsigned short nt_ace_size;
 713
 714                         if (offsetof(struct smb_ace, access_req) > aces_size)
 715                                 break;
 716
 717                         nt_ace_size = le16_to_cpu(ntace->size);
 718                         if (nt_ace_size > aces_size)
 719                                 break;
 720
 721                         memcpy((char *)pndace + size, ntace, nt_ace_size);
 722                         size += nt_ace_size;
 723                         aces_size -= nt_ace_size;
 724                         ntace = (struct smb_ace *)((char *)ntace + nt_ace_size);
 725                         num_aces++;
 726                 }
 727         }
 728
 729         set_posix_acl_entries_dacl(user_ns, pndace, fattr,
 730                                    &num_aces, &size, nt_num_aces);
 731         pndacl->num_aces = cpu_to_le32(num_aces);
 732         pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
 733 }
 734
 735 static void set_mode_dacl(struct user_namespace *user_ns,
 736                           struct smb_acl *pndacl, struct smb_fattr *fattr)
 737 {
 738         struct smb_ace *pace, *pndace;
 739         u32 num_aces = 0;
 740         u16 size = 0, ace_size = 0;
 741         uid_t uid;
 742         const struct smb_sid *sid;
 743
 744         pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
 745
 746         if (fattr->cf_acls) {
 747                 set_posix_acl_entries_dacl(user_ns, pndace, fattr,
 748                                            &num_aces, &size, num_aces);
 749                 goto out;
 750         }
 751
 752         /* owner RID */
 753         uid = from_kuid(&init_user_ns, fattr->cf_uid);
 754         if (uid)
 755                 sid = &server_conf.domain_sid;
 756         else
 757                 sid = &sid_unix_users;
 758         ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0,
 759                                     fattr->cf_mode, 0700);
 760         pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid);
 761         pace->size = cpu_to_le16(ace_size + 4);
 762         size += le16_to_cpu(pace->size);
 763         pace = (struct smb_ace *)((char *)pndace + size);
 764
 765         /* Group RID */
 766         ace_size = fill_ace_for_sid(pace, &sid_unix_groups,
 767                                     ACCESS_ALLOWED, 0, fattr->cf_mode, 0070);
 768         pace->sid.sub_auth[pace->sid.num_subauth++] =
 769                 cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid));
 770         pace->size = cpu_to_le16(ace_size + 4);
 771         size += le16_to_cpu(pace->size);
 772         pace = (struct smb_ace *)((char *)pndace + size);
 773         num_aces = 3;
 774
 775         if (S_ISDIR(fattr->cf_mode)) {
 776                 pace = (struct smb_ace *)((char *)pndace + size);
 777
 778                 /* creator owner */
 779                 size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED,
 780                                          0x0b, fattr->cf_mode, 0700);
 781                 pace = (struct smb_ace *)((char *)pndace + size);
 782
 783                 /* creator group */
 784                 size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED,
 785                                          0x0b, fattr->cf_mode, 0070);
 786                 pace = (struct smb_ace *)((char *)pndace + size);
 787                 num_aces = 5;
 788         }
 789
 790         /* other */
 791         size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0,
 792                                  fattr->cf_mode, 0007);
 793
 794 out:
 795         pndacl->num_aces = cpu_to_le32(num_aces);
 796         pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
 797 }
 798
 799 static int parse_sid(struct smb_sid *psid, char *end_of_acl)
 800 {
 801         /*
 802          * validate that we do not go past end of ACL - sid must be at least 8
 803          * bytes long (assuming no sub-auths - e.g. the null SID
 804          */
 805         if (end_of_acl < (char *)psid + 8) {
 806                 pr_err("ACL too small to parse SID %p\n", psid);
 807                 return -EINVAL;
 808         }
 809
 810         return 0;
 811 }
 812
 813 /* Convert CIFS ACL to POSIX form */
 814 int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
 815                    int acl_len, struct smb_fattr *fattr)
 816 {
 817         int rc = 0;
 818         struct smb_sid *owner_sid_ptr, *group_sid_ptr;
 819         struct smb_acl *dacl_ptr; /* no need for SACL ptr */
 820         char *end_of_acl = ((char *)pntsd) + acl_len;
 821         __u32 dacloffset;
 822         int pntsd_type;
 823
 824         if (!pntsd)
 825                 return -EIO;
 826
 827         if (acl_len < sizeof(struct smb_ntsd))
 828                 return -EINVAL;
 829
 830         owner_sid_ptr = (struct smb_sid *)((char *)pntsd +
 831                         le32_to_cpu(pntsd->osidoffset));
 832         group_sid_ptr = (struct smb_sid *)((char *)pntsd +
 833                         le32_to_cpu(pntsd->gsidoffset));
 834         dacloffset = le32_to_cpu(pntsd->dacloffset);
 835         dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset);
 836         ksmbd_debug(SMB,
 837                     "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n",
 838                     pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
 839                     le32_to_cpu(pntsd->gsidoffset),
 840                     le32_to_cpu(pntsd->sacloffset), dacloffset);
 841
 842         pntsd_type = le16_to_cpu(pntsd->type);
 843         if (!(pntsd_type & DACL_PRESENT)) {
 844                 ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n");
 845                 return rc;
 846         }
 847
 848         pntsd->type = cpu_to_le16(DACL_PRESENT);
 849
 850         if (pntsd->osidoffset) {
 851                 rc = parse_sid(owner_sid_ptr, end_of_acl);
 852                 if (rc) {
 853                         pr_err("%s: Error %d parsing Owner SID\n", __func__, rc);
 854                         return rc;
 855                 }
 856
 857                 rc = sid_to_id(user_ns, owner_sid_ptr, SIDOWNER, fattr);
 858                 if (rc) {
 859                         pr_err("%s: Error %d mapping Owner SID to uid\n",
 860                                __func__, rc);
 861                         owner_sid_ptr = NULL;
 862                 }
 863         }
 864
 865         if (pntsd->gsidoffset) {
 866                 rc = parse_sid(group_sid_ptr, end_of_acl);
 867                 if (rc) {
 868                         pr_err("%s: Error %d mapping Owner SID to gid\n",
 869                                __func__, rc);
 870                         return rc;
 871                 }
 872                 rc = sid_to_id(user_ns, group_sid_ptr, SIDUNIX_GROUP, fattr);
 873                 if (rc) {
 874                         pr_err("%s: Error %d mapping Group SID to gid\n",
 875                                __func__, rc);
 876                         group_sid_ptr = NULL;
 877                 }
 878         }
 879
 880         if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) ==
 881             (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ))
 882                 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
 883         if (pntsd_type & DACL_PROTECTED)
 884                 pntsd->type |= cpu_to_le16(DACL_PROTECTED);
 885
 886         if (dacloffset) {
 887                 parse_dacl(user_ns, dacl_ptr, end_of_acl,
 888                            owner_sid_ptr, group_sid_ptr, fattr);
 889         }
 890
 891         return 0;
 892 }
 893
 894 /* Convert permission bits from mode to equivalent CIFS ACL */
 895 int build_sec_desc(struct user_namespace *user_ns,
 896                    struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
 897                    int ppntsd_size, int addition_info, __u32 *secdesclen,
 898                    struct smb_fattr *fattr)
 899 {
 900         int rc = 0;
 901         __u32 offset;
 902         struct smb_sid *owner_sid_ptr, *group_sid_ptr;
 903         struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr;
 904         struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */
 905         uid_t uid;
 906         gid_t gid;
 907         unsigned int sid_type = SIDOWNER;
 908
 909         nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 910         if (!nowner_sid_ptr)
 911                 return -ENOMEM;
 912
 913         uid = from_kuid(&init_user_ns, fattr->cf_uid);
 914         if (!uid)
 915                 sid_type = SIDUNIX_USER;
 916         id_to_sid(uid, sid_type, nowner_sid_ptr);
 917
 918         ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 919         if (!ngroup_sid_ptr) {
 920                 kfree(nowner_sid_ptr);
 921                 return -ENOMEM;
 922         }
 923
 924         gid = from_kgid(&init_user_ns, fattr->cf_gid);
 925         id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr);
 926
 927         offset = sizeof(struct smb_ntsd);
 928         pntsd->sacloffset = 0;
 929         pntsd->revision = cpu_to_le16(1);
 930         pntsd->type = cpu_to_le16(SELF_RELATIVE);
 931         if (ppntsd)
 932                 pntsd->type |= ppntsd->type;
 933
 934         if (addition_info & OWNER_SECINFO) {
 935                 pntsd->osidoffset = cpu_to_le32(offset);
 936                 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
 937                 smb_copy_sid(owner_sid_ptr, nowner_sid_ptr);
 938                 offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4);
 939         }
 940
 941         if (addition_info & GROUP_SECINFO) {
 942                 pntsd->gsidoffset = cpu_to_le32(offset);
 943                 group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
 944                 smb_copy_sid(group_sid_ptr, ngroup_sid_ptr);
 945                 offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4);
 946         }
 947
 948         if (addition_info & DACL_SECINFO) {
 949                 pntsd->type |= cpu_to_le16(DACL_PRESENT);
 950                 dacl_ptr = (struct smb_acl *)((char *)pntsd + offset);
 951                 dacl_ptr->revision = cpu_to_le16(2);
 952                 dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl));
 953                 dacl_ptr->num_aces = 0;
 954
 955                 if (!ppntsd) {
 956                         set_mode_dacl(user_ns, dacl_ptr, fattr);
 957                 } else {
 958                         struct smb_acl *ppdacl_ptr;
 959                         unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset);
 960                         int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset;
 961
 962                         if (!dacl_offset ||
 963                             (dacl_offset + sizeof(struct smb_acl) > ppntsd_size))
 964                                 goto out;
 965
 966                         ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset);
 967                         ppdacl_size = le16_to_cpu(ppdacl_ptr->size);
 968                         if (ppdacl_size > ntacl_size ||
 969                             ppdacl_size < sizeof(struct smb_acl))
 970                                 goto out;
 971
 972                         set_ntacl_dacl(user_ns, dacl_ptr, ppdacl_ptr,
 973                                        ntacl_size - sizeof(struct smb_acl),
 974                                        nowner_sid_ptr, ngroup_sid_ptr,
 975                                        fattr);
 976                 }
 977                 pntsd->dacloffset = cpu_to_le32(offset);
 978                 offset += le16_to_cpu(dacl_ptr->size);
 979         }
 980
 981 out:
 982         kfree(nowner_sid_ptr);
 983         kfree(ngroup_sid_ptr);
 984         *secdesclen = offset;
 985         return rc;
 986 }
 987
 988 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type,
 989                         u8 flags, __le32 access_req)
 990 {
 991         ace->type = type;
 992         ace->flags = flags;
 993         ace->access_req = access_req;
 994         smb_copy_sid(&ace->sid, sid);
 995         ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + (sid->num_subauth * 4));
 996 }
 997
 998 int smb_inherit_dacl(struct ksmbd_conn *conn,
 999                      const struct path *path,
1000                      unsigned int uid, unsigned int gid)
1001 {
1002         const struct smb_sid *psid, *creator = NULL;
1003         struct smb_ace *parent_aces, *aces;
1004         struct smb_acl *parent_pdacl;
1005         struct smb_ntsd *parent_pntsd = NULL;
1006         struct smb_sid owner_sid, group_sid;
1007         struct dentry *parent = path->dentry->d_parent;
1008         struct user_namespace *user_ns = mnt_user_ns(path->mnt);
1009         int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size;
1010         int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size;
1011         char *aces_base;
1012         bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
1013
1014         pntsd_size = ksmbd_vfs_get_sd_xattr(conn, user_ns,
1015                                             parent, &parent_pntsd);
1016         if (pntsd_size <= 0)
1017                 return -ENOENT;
1018         dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
1019         if (!dacloffset || (dacloffset + sizeof(struct smb_acl) > pntsd_size)) {
1020                 rc = -EINVAL;
1021                 goto free_parent_pntsd;
1022         }
1023
1024         parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset);
1025         acl_len = pntsd_size - dacloffset;
1026         num_aces = le32_to_cpu(parent_pdacl->num_aces);
1027         pntsd_type = le16_to_cpu(parent_pntsd->type);
1028         pdacl_size = le16_to_cpu(parent_pdacl->size);
1029
1030         if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) {
1031                 rc = -EINVAL;
1032                 goto free_parent_pntsd;
1033         }
1034
1035         aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL);
1036         if (!aces_base) {
1037                 rc = -ENOMEM;
1038                 goto free_parent_pntsd;
1039         }
1040
1041         aces = (struct smb_ace *)aces_base;
1042         parent_aces = (struct smb_ace *)((char *)parent_pdacl +
1043                         sizeof(struct smb_acl));
1044         aces_size = acl_len - sizeof(struct smb_acl);
1045
1046         if (pntsd_type & DACL_AUTO_INHERITED)
1047                 inherited_flags = INHERITED_ACE;
1048
1049         for (i = 0; i < num_aces; i++) {
1050                 int pace_size;
1051
1052                 if (offsetof(struct smb_ace, access_req) > aces_size)
1053                         break;
1054
1055                 pace_size = le16_to_cpu(parent_aces->size);
1056                 if (pace_size > aces_size)
1057                         break;
1058
1059                 aces_size -= pace_size;
1060
1061                 flags = parent_aces->flags;
1062                 if (!smb_inherit_flags(flags, is_dir))
1063                         goto pass;
1064                 if (is_dir) {
1065                         flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE);
1066                         if (!(flags & CONTAINER_INHERIT_ACE))
1067                                 flags |= INHERIT_ONLY_ACE;
1068                         if (flags & NO_PROPAGATE_INHERIT_ACE)
1069                                 flags = 0;
1070                 } else {
1071                         flags = 0;
1072                 }
1073
1074                 if (!compare_sids(&creator_owner, &parent_aces->sid)) {
1075                         creator = &creator_owner;
1076                         id_to_sid(uid, SIDOWNER, &owner_sid);
1077                         psid = &owner_sid;
1078                 } else if (!compare_sids(&creator_group, &parent_aces->sid)) {
1079                         creator = &creator_group;
1080                         id_to_sid(gid, SIDUNIX_GROUP, &group_sid);
1081                         psid = &group_sid;
1082                 } else {
1083                         creator = NULL;
1084                         psid = &parent_aces->sid;
1085                 }
1086
1087                 if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) {
1088                         smb_set_ace(aces, psid, parent_aces->type, inherited_flags,
1089                                     parent_aces->access_req);
1090                         nt_size += le16_to_cpu(aces->size);
1091                         ace_cnt++;
1092                         aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1093                         flags |= INHERIT_ONLY_ACE;
1094                         psid = creator;
1095                 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) {
1096                         psid = &parent_aces->sid;
1097                 }
1098
1099                 smb_set_ace(aces, psid, parent_aces->type, flags | inherited_flags,
1100                             parent_aces->access_req);
1101                 nt_size += le16_to_cpu(aces->size);
1102                 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1103                 ace_cnt++;
1104 pass:
1105                 parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size);
1106         }
1107
1108         if (nt_size > 0) {
1109                 struct smb_ntsd *pntsd;
1110                 struct smb_acl *pdacl;
1111                 struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL;
1112                 int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size;
1113                 int pntsd_alloc_size;
1114
1115                 if (parent_pntsd->osidoffset) {
1116                         powner_sid = (struct smb_sid *)((char *)parent_pntsd +
1117                                         le32_to_cpu(parent_pntsd->osidoffset));
1118                         powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4);
1119                 }
1120                 if (parent_pntsd->gsidoffset) {
1121                         pgroup_sid = (struct smb_sid *)((char *)parent_pntsd +
1122                                         le32_to_cpu(parent_pntsd->gsidoffset));
1123                         pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4);
1124                 }
1125
1126                 pntsd_alloc_size = sizeof(struct smb_ntsd) + powner_sid_size +
1127                         pgroup_sid_size + sizeof(struct smb_acl) + nt_size;
1128
1129                 pntsd = kzalloc(pntsd_alloc_size, GFP_KERNEL);
1130                 if (!pntsd) {
1131                         rc = -ENOMEM;
1132                         goto free_aces_base;
1133                 }
1134
1135                 pntsd->revision = cpu_to_le16(1);
1136                 pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT);
1137                 if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED)
1138                         pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
1139                 pntsd_size = sizeof(struct smb_ntsd);
1140                 pntsd->osidoffset = parent_pntsd->osidoffset;
1141                 pntsd->gsidoffset = parent_pntsd->gsidoffset;
1142                 pntsd->dacloffset = parent_pntsd->dacloffset;
1143
1144                 if ((u64)le32_to_cpu(pntsd->osidoffset) + powner_sid_size >
1145                     pntsd_alloc_size) {
1146                         rc = -EINVAL;
1147                         kfree(pntsd);
1148                         goto free_aces_base;
1149                 }
1150
1151                 if ((u64)le32_to_cpu(pntsd->gsidoffset) + pgroup_sid_size >
1152                     pntsd_alloc_size) {
1153                         rc = -EINVAL;
1154                         kfree(pntsd);
1155                         goto free_aces_base;
1156                 }
1157
1158                 if ((u64)le32_to_cpu(pntsd->dacloffset) + sizeof(struct smb_acl) + nt_size >
1159                     pntsd_alloc_size) {
1160                         rc = -EINVAL;
1161                         kfree(pntsd);
1162                         goto free_aces_base;
1163                 }
1164
1165                 if (pntsd->osidoffset) {
1166                         struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd +
1167                                         le32_to_cpu(pntsd->osidoffset));
1168                         memcpy(owner_sid, powner_sid, powner_sid_size);
1169                         pntsd_size += powner_sid_size;
1170                 }
1171
1172                 if (pntsd->gsidoffset) {
1173                         struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd +
1174                                         le32_to_cpu(pntsd->gsidoffset));
1175                         memcpy(group_sid, pgroup_sid, pgroup_sid_size);
1176                         pntsd_size += pgroup_sid_size;
1177                 }
1178
1179                 if (pntsd->dacloffset) {
1180                         struct smb_ace *pace;
1181
1182                         pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1183                         pdacl->revision = cpu_to_le16(2);
1184                         pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size);
1185                         pdacl->num_aces = cpu_to_le32(ace_cnt);
1186                         pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1187                         memcpy(pace, aces_base, nt_size);
1188                         pntsd_size += sizeof(struct smb_acl) + nt_size;
1189                 }
1190
1191                 ksmbd_vfs_set_sd_xattr(conn, user_ns, path, pntsd, pntsd_size, false);
1192                 kfree(pntsd);
1193         }
1194
1195 free_aces_base:
1196         kfree(aces_base);
1197 free_parent_pntsd:
1198         kfree(parent_pntsd);
1199         return rc;
1200 }
1201
1202 bool smb_inherit_flags(int flags, bool is_dir)
1203 {
1204         if (!is_dir)
1205                 return (flags & OBJECT_INHERIT_ACE) != 0;
1206
1207         if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE))
1208                 return true;
1209
1210         if (flags & CONTAINER_INHERIT_ACE)
1211                 return true;
1212         return false;
1213 }
1214
1215 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
1216                         __le32 *pdaccess, int uid)
1217 {
1218         struct user_namespace *user_ns = mnt_user_ns(path->mnt);
1219         struct smb_ntsd *pntsd = NULL;
1220         struct smb_acl *pdacl;
1221         struct posix_acl *posix_acls;
1222         int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size, dacl_offset;
1223         struct smb_sid sid;
1224         int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
1225         struct smb_ace *ace;
1226         int i, found = 0;
1227         unsigned int access_bits = 0;
1228         struct smb_ace *others_ace = NULL;
1229         struct posix_acl_entry *pa_entry;
1230         unsigned int sid_type = SIDOWNER;
1231         unsigned short ace_size;
1232
1233         ksmbd_debug(SMB, "check permission using windows acl\n");
1234         pntsd_size = ksmbd_vfs_get_sd_xattr(conn, user_ns,
1235                                             path->dentry, &pntsd);
1236         if (pntsd_size <= 0 || !pntsd)
1237                 goto err_out;
1238
1239         dacl_offset = le32_to_cpu(pntsd->dacloffset);
1240         if (!dacl_offset ||
1241             (dacl_offset + sizeof(struct smb_acl) > pntsd_size))
1242                 goto err_out;
1243
1244         pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1245         acl_size = pntsd_size - dacl_offset;
1246         pdacl_size = le16_to_cpu(pdacl->size);
1247
1248         if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl))
1249                 goto err_out;
1250
1251         if (!pdacl->num_aces) {
1252                 if (!(pdacl_size - sizeof(struct smb_acl)) &&
1253                     *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) {
1254                         rc = -EACCES;
1255                         goto err_out;
1256                 }
1257                 goto err_out;
1258         }
1259
1260         if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
1261                 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1262                         DELETE;
1263
1264                 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1265                 aces_size = acl_size - sizeof(struct smb_acl);
1266                 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1267                         if (offsetof(struct smb_ace, access_req) > aces_size)
1268                                 break;
1269                         ace_size = le16_to_cpu(ace->size);
1270                         if (ace_size > aces_size)
1271                                 break;
1272                         aces_size -= ace_size;
1273                         granted |= le32_to_cpu(ace->access_req);
1274                         ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1275                 }
1276
1277                 if (!pdacl->num_aces)
1278                         granted = GENERIC_ALL_FLAGS;
1279         }
1280
1281         if (!uid)
1282                 sid_type = SIDUNIX_USER;
1283         id_to_sid(uid, sid_type, &sid);
1284
1285         ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1286         aces_size = acl_size - sizeof(struct smb_acl);
1287         for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1288                 if (offsetof(struct smb_ace, access_req) > aces_size)
1289                         break;
1290                 ace_size = le16_to_cpu(ace->size);
1291                 if (ace_size > aces_size)
1292                         break;
1293                 aces_size -= ace_size;
1294
1295                 if (!compare_sids(&sid, &ace->sid) ||
1296                     !compare_sids(&sid_unix_NFS_mode, &ace->sid)) {
1297                         found = 1;
1298                         break;
1299                 }
1300                 if (!compare_sids(&sid_everyone, &ace->sid))
1301                         others_ace = ace;
1302
1303                 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1304         }
1305
1306         if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
1307                 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1308                         DELETE;
1309
1310                 granted |= le32_to_cpu(ace->access_req);
1311
1312                 if (!pdacl->num_aces)
1313                         granted = GENERIC_ALL_FLAGS;
1314         }
1315
1316         if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
1317                 posix_acls = get_acl(d_inode(path->dentry), ACL_TYPE_ACCESS);
1318                 if (!IS_ERR_OR_NULL(posix_acls) && !found) {
1319                         unsigned int id = -1;
1320
1321                         pa_entry = posix_acls->a_entries;
1322                         for (i = 0; i < posix_acls->a_count; i++, pa_entry++) {
1323                                 if (pa_entry->e_tag == ACL_USER)
1324                                         id = posix_acl_uid_translate(user_ns, pa_entry);
1325                                 else if (pa_entry->e_tag == ACL_GROUP)
1326                                         id = posix_acl_gid_translate(user_ns, pa_entry);
1327                                 else
1328                                         continue;
1329
1330                                 if (id == uid) {
1331                                         mode_to_access_flags(pa_entry->e_perm,
1332                                                              0777,
1333                                                              &access_bits);
1334                                         if (!access_bits)
1335                                                 access_bits =
1336                                                         SET_MINIMUM_RIGHTS;
1337                                         posix_acl_release(posix_acls);
1338                                         goto check_access_bits;
1339                                 }
1340                         }
1341                 }
1342                 if (!IS_ERR_OR_NULL(posix_acls))
1343                         posix_acl_release(posix_acls);
1344         }
1345
1346         if (!found) {
1347                 if (others_ace) {
1348                         ace = others_ace;
1349                 } else {
1350                         ksmbd_debug(SMB, "Can't find corresponding sid\n");
1351                         rc = -EACCES;
1352                         goto err_out;
1353                 }
1354         }
1355
1356         switch (ace->type) {
1357         case ACCESS_ALLOWED_ACE_TYPE:
1358                 access_bits = le32_to_cpu(ace->access_req);
1359                 break;
1360         case ACCESS_DENIED_ACE_TYPE:
1361         case ACCESS_DENIED_CALLBACK_ACE_TYPE:
1362                 access_bits = le32_to_cpu(~ace->access_req);
1363                 break;
1364         }
1365
1366 check_access_bits:
1367         if (granted &
1368             ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) {
1369                 ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n",
1370                             granted, le32_to_cpu(ace->access_req));
1371                 rc = -EACCES;
1372                 goto err_out;
1373         }
1374
1375         *pdaccess = cpu_to_le32(granted);
1376 err_out:
1377         kfree(pntsd);
1378         return rc;
1379 }
1380
1381 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
1382                  const struct path *path, struct smb_ntsd *pntsd, int ntsd_len,
1383                  bool type_check, bool get_write)
1384 {
1385         int rc;
1386         struct smb_fattr fattr = {{0}};
1387         struct inode *inode = d_inode(path->dentry);
1388         struct user_namespace *user_ns = mnt_user_ns(path->mnt);
1389         struct iattr newattrs;
1390
1391         fattr.cf_uid = INVALID_UID;
1392         fattr.cf_gid = INVALID_GID;
1393         fattr.cf_mode = inode->i_mode;
1394
1395         rc = parse_sec_desc(user_ns, pntsd, ntsd_len, &fattr);
1396         if (rc)
1397                 goto out;
1398
1399         newattrs.ia_valid = ATTR_CTIME;
1400         if (!uid_eq(fattr.cf_uid, INVALID_UID)) {
1401                 newattrs.ia_valid |= ATTR_UID;
1402                 newattrs.ia_uid = fattr.cf_uid;
1403         }
1404         if (!gid_eq(fattr.cf_gid, INVALID_GID)) {
1405                 newattrs.ia_valid |= ATTR_GID;
1406                 newattrs.ia_gid = fattr.cf_gid;
1407         }
1408         newattrs.ia_valid |= ATTR_MODE;
1409         newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
1410
1411         ksmbd_vfs_remove_acl_xattrs(user_ns, path);
1412         /* Update posix acls */
1413         if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) {
1414                 rc = set_posix_acl(user_ns, inode,
1415                                    ACL_TYPE_ACCESS, fattr.cf_acls);
1416                 if (rc < 0)
1417                         ksmbd_debug(SMB,
1418                                     "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
1419                                     rc);
1420                 if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) {
1421                         rc = set_posix_acl(user_ns, inode,
1422                                            ACL_TYPE_DEFAULT, fattr.cf_dacls);
1423                         if (rc)
1424                                 ksmbd_debug(SMB,
1425                                             "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n",
1426                                             rc);
1427                 }
1428         }
1429
1430         inode_lock(inode);
1431         rc = notify_change(user_ns, path->dentry, &newattrs, NULL);
1432         inode_unlock(inode);
1433         if (rc)
1434                 goto out;
1435
1436         /* Check it only calling from SD BUFFER context */
1437         if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT))
1438                 goto out;
1439
1440         if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) {
1441                 /* Update WinACL in xattr */
1442                 ksmbd_vfs_remove_sd_xattrs(user_ns, path);
1443                 ksmbd_vfs_set_sd_xattr(conn, user_ns, path, pntsd, ntsd_len,
1444                                 get_write);
1445         }
1446
1447 out:
1448         posix_acl_release(fattr.cf_acls);
1449         posix_acl_release(fattr.cf_dacls);
1450         return rc;
1451 }
1452
1453 void ksmbd_init_domain(u32 *sub_auth)
1454 {
1455         int i;
1456
1457         memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid));
1458         for (i = 0; i < 3; ++i)
1459                 server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]);
1460 }