fs/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 = 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 mnt_idmap *idmap,
 258                      struct smb_sid *psid, uint sidtype,
 259                      struct smb_fattr *fattr)
 260 {
 261         int rc = -EINVAL;
 262
 263         /*
 264          * If we have too many subauthorities, then something is really wrong.
 265          * Just return an error.
 266          */
 267         if (unlikely(psid->num_subauth > SID_MAX_SUB_AUTHORITIES)) {
 268                 pr_err("%s: %u subauthorities is too many!\n",
 269                        __func__, psid->num_subauth);
 270                 return -EIO;
 271         }
 272
 273         if (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(idmap, &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(idmap, &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 mnt_idmap *idmap,
 366                        struct smb_acl *pdacl, char *end_of_acl,
 367                        struct smb_sid *pownersid, struct smb_sid *pgrpsid,
 368                        struct smb_fattr *fattr)
 369 {
 370         int i, ret;
 371         int num_aces = 0;
 372         unsigned int acl_size;
 373         char *acl_base;
 374         struct smb_ace **ppace;
 375         struct posix_acl_entry *cf_pace, *cf_pdace;
 376         struct posix_acl_state acl_state, default_acl_state;
 377         umode_t mode = 0, acl_mode;
 378         bool owner_found = false, group_found = false, others_found = false;
 379
 380         if (!pdacl)
 381                 return;
 382
 383         /* validate that we do not go past end of acl */
 384         if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) ||
 385             end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) {
 386                 pr_err("ACL too small to parse DACL\n");
 387                 return;
 388         }
 389
 390         ksmbd_debug(SMB, "DACL revision %d size %d num aces %d\n",
 391                     le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size),
 392                     le32_to_cpu(pdacl->num_aces));
 393
 394         acl_base = (char *)pdacl;
 395         acl_size = sizeof(struct smb_acl);
 396
 397         num_aces = le32_to_cpu(pdacl->num_aces);
 398         if (num_aces <= 0)
 399                 return;
 400
 401         if (num_aces > ULONG_MAX / sizeof(struct smb_ace *))
 402                 return;
 403
 404         ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL);
 405         if (!ppace)
 406                 return;
 407
 408         ret = init_acl_state(&acl_state, num_aces);
 409         if (ret)
 410                 return;
 411         ret = init_acl_state(&default_acl_state, num_aces);
 412         if (ret) {
 413                 free_acl_state(&acl_state);
 414                 return;
 415         }
 416
 417         /*
 418          * reset rwx permissions for user/group/other.
 419          * Also, if num_aces is 0 i.e. DACL has no ACEs,
 420          * user/group/other have no permissions
 421          */
 422         for (i = 0; i < num_aces; ++i) {
 423                 if (end_of_acl - acl_base < acl_size)
 424                         break;
 425
 426                 ppace[i] = (struct smb_ace *)(acl_base + acl_size);
 427                 acl_base = (char *)ppace[i];
 428                 acl_size = offsetof(struct smb_ace, sid) +
 429                         offsetof(struct smb_sid, sub_auth);
 430
 431                 if (end_of_acl - acl_base < acl_size ||
 432                     ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES ||
 433                     (end_of_acl - acl_base <
 434                      acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) ||
 435                     (le16_to_cpu(ppace[i]->size) <
 436                      acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth))
 437                         break;
 438
 439                 acl_size = le16_to_cpu(ppace[i]->size);
 440                 ppace[i]->access_req =
 441                         smb_map_generic_desired_access(ppace[i]->access_req);
 442
 443                 if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) {
 444                         fattr->cf_mode =
 445                                 le32_to_cpu(ppace[i]->sid.sub_auth[2]);
 446                         break;
 447                 } else if (!compare_sids(&ppace[i]->sid, pownersid)) {
 448                         acl_mode = access_flags_to_mode(fattr,
 449                                                         ppace[i]->access_req,
 450                                                         ppace[i]->type);
 451                         acl_mode &= 0700;
 452
 453                         if (!owner_found) {
 454                                 mode &= ~(0700);
 455                                 mode |= acl_mode;
 456                         }
 457                         owner_found = true;
 458                 } else if (!compare_sids(&ppace[i]->sid, pgrpsid) ||
 459                            ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] ==
 460                             DOMAIN_USER_RID_LE) {
 461                         acl_mode = access_flags_to_mode(fattr,
 462                                                         ppace[i]->access_req,
 463                                                         ppace[i]->type);
 464                         acl_mode &= 0070;
 465                         if (!group_found) {
 466                                 mode &= ~(0070);
 467                                 mode |= acl_mode;
 468                         }
 469                         group_found = true;
 470                 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) {
 471                         acl_mode = access_flags_to_mode(fattr,
 472                                                         ppace[i]->access_req,
 473                                                         ppace[i]->type);
 474                         acl_mode &= 0007;
 475                         if (!others_found) {
 476                                 mode &= ~(0007);
 477                                 mode |= acl_mode;
 478                         }
 479                         others_found = true;
 480                 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) {
 481                         continue;
 482                 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) {
 483                         continue;
 484                 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) {
 485                         continue;
 486                 } else {
 487                         struct smb_fattr temp_fattr;
 488
 489                         acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
 490                                                         ppace[i]->type);
 491                         temp_fattr.cf_uid = INVALID_UID;
 492                         ret = sid_to_id(idmap, &ppace[i]->sid, SIDOWNER, &temp_fattr);
 493                         if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) {
 494                                 pr_err("%s: Error %d mapping Owner SID to uid\n",
 495                                        __func__, ret);
 496                                 continue;
 497                         }
 498
 499                         acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
 500                         acl_state.users->aces[acl_state.users->n].uid =
 501                                 temp_fattr.cf_uid;
 502                         acl_state.users->aces[acl_state.users->n++].perms.allow =
 503                                 ((acl_mode & 0700) >> 6) | 0004;
 504                         default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
 505                         default_acl_state.users->aces[default_acl_state.users->n].uid =
 506                                 temp_fattr.cf_uid;
 507                         default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
 508                                 ((acl_mode & 0700) >> 6) | 0004;
 509                 }
 510         }
 511         kfree(ppace);
 512
 513         if (owner_found) {
 514                 /* The owner must be set to at least read-only. */
 515                 acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
 516                 acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid;
 517                 acl_state.users->aces[acl_state.users->n++].perms.allow =
 518                         ((mode & 0700) >> 6) | 0004;
 519                 default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
 520                 default_acl_state.users->aces[default_acl_state.users->n].uid =
 521                         fattr->cf_uid;
 522                 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
 523                         ((mode & 0700) >> 6) | 0004;
 524         }
 525
 526         if (group_found) {
 527                 acl_state.group.allow = (mode & 0070) >> 3;
 528                 acl_state.groups->aces[acl_state.groups->n].gid =
 529                         fattr->cf_gid;
 530                 acl_state.groups->aces[acl_state.groups->n++].perms.allow =
 531                         (mode & 0070) >> 3;
 532                 default_acl_state.group.allow = (mode & 0070) >> 3;
 533                 default_acl_state.groups->aces[default_acl_state.groups->n].gid =
 534                         fattr->cf_gid;
 535                 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow =
 536                         (mode & 0070) >> 3;
 537         }
 538
 539         if (others_found) {
 540                 fattr->cf_mode &= ~(0007);
 541                 fattr->cf_mode |= mode & 0007;
 542
 543                 acl_state.other.allow = mode & 0007;
 544                 default_acl_state.other.allow = mode & 0007;
 545         }
 546
 547         if (acl_state.users->n || acl_state.groups->n) {
 548                 acl_state.mask.allow = 0x07;
 549
 550                 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
 551                         fattr->cf_acls =
 552                                 posix_acl_alloc(acl_state.users->n +
 553                                         acl_state.groups->n + 4, GFP_KERNEL);
 554                         if (fattr->cf_acls) {
 555                                 cf_pace = fattr->cf_acls->a_entries;
 556                                 posix_state_to_acl(&acl_state, cf_pace);
 557                         }
 558                 }
 559         }
 560
 561         if (default_acl_state.users->n || default_acl_state.groups->n) {
 562                 default_acl_state.mask.allow = 0x07;
 563
 564                 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
 565                         fattr->cf_dacls =
 566                                 posix_acl_alloc(default_acl_state.users->n +
 567                                 default_acl_state.groups->n + 4, GFP_KERNEL);
 568                         if (fattr->cf_dacls) {
 569                                 cf_pdace = fattr->cf_dacls->a_entries;
 570                                 posix_state_to_acl(&default_acl_state, cf_pdace);
 571                         }
 572                 }
 573         }
 574         free_acl_state(&acl_state);
 575         free_acl_state(&default_acl_state);
 576 }
 577
 578 static void set_posix_acl_entries_dacl(struct mnt_idmap *idmap,
 579                                        struct smb_ace *pndace,
 580                                        struct smb_fattr *fattr, u32 *num_aces,
 581                                        u16 *size, u32 nt_aces_num)
 582 {
 583         struct posix_acl_entry *pace;
 584         struct smb_sid *sid;
 585         struct smb_ace *ntace;
 586         int i, j;
 587
 588         if (!fattr->cf_acls)
 589                 goto posix_default_acl;
 590
 591         pace = fattr->cf_acls->a_entries;
 592         for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) {
 593                 int flags = 0;
 594
 595                 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 596                 if (!sid)
 597                         break;
 598
 599                 if (pace->e_tag == ACL_USER) {
 600                         uid_t uid;
 601                         unsigned int sid_type = SIDOWNER;
 602
 603                         uid = posix_acl_uid_translate(idmap, pace);
 604                         if (!uid)
 605                                 sid_type = SIDUNIX_USER;
 606                         id_to_sid(uid, sid_type, sid);
 607                 } else if (pace->e_tag == ACL_GROUP) {
 608                         gid_t gid;
 609
 610                         gid = posix_acl_gid_translate(idmap, pace);
 611                         id_to_sid(gid, SIDUNIX_GROUP, sid);
 612                 } else if (pace->e_tag == ACL_OTHER && !nt_aces_num) {
 613                         smb_copy_sid(sid, &sid_everyone);
 614                 } else {
 615                         kfree(sid);
 616                         continue;
 617                 }
 618                 ntace = pndace;
 619                 for (j = 0; j < nt_aces_num; j++) {
 620                         if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] ==
 621                                         sid->sub_auth[sid->num_subauth - 1])
 622                                 goto pass_same_sid;
 623                         ntace = (struct smb_ace *)((char *)ntace +
 624                                         le16_to_cpu(ntace->size));
 625                 }
 626
 627                 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER)
 628                         flags = 0x03;
 629
 630                 ntace = (struct smb_ace *)((char *)pndace + *size);
 631                 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags,
 632                                 pace->e_perm, 0777);
 633                 (*num_aces)++;
 634                 if (pace->e_tag == ACL_USER)
 635                         ntace->access_req |=
 636                                 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
 637
 638                 if (S_ISDIR(fattr->cf_mode) &&
 639                     (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) {
 640                         ntace = (struct smb_ace *)((char *)pndace + *size);
 641                         *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED,
 642                                         0x03, pace->e_perm, 0777);
 643                         (*num_aces)++;
 644                         if (pace->e_tag == ACL_USER)
 645                                 ntace->access_req |=
 646                                         FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
 647                 }
 648
 649 pass_same_sid:
 650                 kfree(sid);
 651         }
 652
 653         if (nt_aces_num)
 654                 return;
 655
 656 posix_default_acl:
 657         if (!fattr->cf_dacls)
 658                 return;
 659
 660         pace = fattr->cf_dacls->a_entries;
 661         for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) {
 662                 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 663                 if (!sid)
 664                         break;
 665
 666                 if (pace->e_tag == ACL_USER) {
 667                         uid_t uid;
 668
 669                         uid = posix_acl_uid_translate(idmap, pace);
 670                         id_to_sid(uid, SIDCREATOR_OWNER, sid);
 671                 } else if (pace->e_tag == ACL_GROUP) {
 672                         gid_t gid;
 673
 674                         gid = posix_acl_gid_translate(idmap, pace);
 675                         id_to_sid(gid, SIDCREATOR_GROUP, sid);
 676                 } else {
 677                         kfree(sid);
 678                         continue;
 679                 }
 680
 681                 ntace = (struct smb_ace *)((char *)pndace + *size);
 682                 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b,
 683                                 pace->e_perm, 0777);
 684                 (*num_aces)++;
 685                 if (pace->e_tag == ACL_USER)
 686                         ntace->access_req |=
 687                                 FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
 688                 kfree(sid);
 689         }
 690 }
 691
 692 static void set_ntacl_dacl(struct mnt_idmap *idmap,
 693                            struct smb_acl *pndacl,
 694                            struct smb_acl *nt_dacl,
 695                            unsigned int aces_size,
 696                            const struct smb_sid *pownersid,
 697                            const struct smb_sid *pgrpsid,
 698                            struct smb_fattr *fattr)
 699 {
 700         struct smb_ace *ntace, *pndace;
 701         int nt_num_aces = le32_to_cpu(nt_dacl->num_aces), num_aces = 0;
 702         unsigned short size = 0;
 703         int i;
 704
 705         pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
 706         if (nt_num_aces) {
 707                 ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl));
 708                 for (i = 0; i < nt_num_aces; i++) {
 709                         unsigned short nt_ace_size;
 710
 711                         if (offsetof(struct smb_ace, access_req) > aces_size)
 712                                 break;
 713
 714                         nt_ace_size = le16_to_cpu(ntace->size);
 715                         if (nt_ace_size > aces_size)
 716                                 break;
 717
 718                         memcpy((char *)pndace + size, ntace, nt_ace_size);
 719                         size += nt_ace_size;
 720                         aces_size -= nt_ace_size;
 721                         ntace = (struct smb_ace *)((char *)ntace + nt_ace_size);
 722                         num_aces++;
 723                 }
 724         }
 725
 726         set_posix_acl_entries_dacl(idmap, pndace, fattr,
 727                                    &num_aces, &size, nt_num_aces);
 728         pndacl->num_aces = cpu_to_le32(num_aces);
 729         pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
 730 }
 731
 732 static void set_mode_dacl(struct mnt_idmap *idmap,
 733                           struct smb_acl *pndacl, struct smb_fattr *fattr)
 734 {
 735         struct smb_ace *pace, *pndace;
 736         u32 num_aces = 0;
 737         u16 size = 0, ace_size = 0;
 738         uid_t uid;
 739         const struct smb_sid *sid;
 740
 741         pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
 742
 743         if (fattr->cf_acls) {
 744                 set_posix_acl_entries_dacl(idmap, pndace, fattr,
 745                                            &num_aces, &size, num_aces);
 746                 goto out;
 747         }
 748
 749         /* owner RID */
 750         uid = from_kuid(&init_user_ns, fattr->cf_uid);
 751         if (uid)
 752                 sid = &server_conf.domain_sid;
 753         else
 754                 sid = &sid_unix_users;
 755         ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0,
 756                                     fattr->cf_mode, 0700);
 757         pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid);
 758         pace->size = cpu_to_le16(ace_size + 4);
 759         size += le16_to_cpu(pace->size);
 760         pace = (struct smb_ace *)((char *)pndace + size);
 761
 762         /* Group RID */
 763         ace_size = fill_ace_for_sid(pace, &sid_unix_groups,
 764                                     ACCESS_ALLOWED, 0, fattr->cf_mode, 0070);
 765         pace->sid.sub_auth[pace->sid.num_subauth++] =
 766                 cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid));
 767         pace->size = cpu_to_le16(ace_size + 4);
 768         size += le16_to_cpu(pace->size);
 769         pace = (struct smb_ace *)((char *)pndace + size);
 770         num_aces = 3;
 771
 772         if (S_ISDIR(fattr->cf_mode)) {
 773                 pace = (struct smb_ace *)((char *)pndace + size);
 774
 775                 /* creator owner */
 776                 size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED,
 777                                          0x0b, fattr->cf_mode, 0700);
 778                 pace = (struct smb_ace *)((char *)pndace + size);
 779
 780                 /* creator group */
 781                 size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED,
 782                                          0x0b, fattr->cf_mode, 0070);
 783                 pace = (struct smb_ace *)((char *)pndace + size);
 784                 num_aces = 5;
 785         }
 786
 787         /* other */
 788         size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0,
 789                                  fattr->cf_mode, 0007);
 790
 791 out:
 792         pndacl->num_aces = cpu_to_le32(num_aces);
 793         pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
 794 }
 795
 796 static int parse_sid(struct smb_sid *psid, char *end_of_acl)
 797 {
 798         /*
 799          * validate that we do not go past end of ACL - sid must be at least 8
 800          * bytes long (assuming no sub-auths - e.g. the null SID
 801          */
 802         if (end_of_acl < (char *)psid + 8) {
 803                 pr_err("ACL too small to parse SID %p\n", psid);
 804                 return -EINVAL;
 805         }
 806
 807         return 0;
 808 }
 809
 810 /* Convert CIFS ACL to POSIX form */
 811 int parse_sec_desc(struct mnt_idmap *idmap, struct smb_ntsd *pntsd,
 812                    int acl_len, struct smb_fattr *fattr)
 813 {
 814         int rc = 0;
 815         struct smb_sid *owner_sid_ptr, *group_sid_ptr;
 816         struct smb_acl *dacl_ptr; /* no need for SACL ptr */
 817         char *end_of_acl = ((char *)pntsd) + acl_len;
 818         __u32 dacloffset;
 819         int pntsd_type;
 820
 821         if (!pntsd)
 822                 return -EIO;
 823
 824         if (acl_len < sizeof(struct smb_ntsd))
 825                 return -EINVAL;
 826
 827         owner_sid_ptr = (struct smb_sid *)((char *)pntsd +
 828                         le32_to_cpu(pntsd->osidoffset));
 829         group_sid_ptr = (struct smb_sid *)((char *)pntsd +
 830                         le32_to_cpu(pntsd->gsidoffset));
 831         dacloffset = le32_to_cpu(pntsd->dacloffset);
 832         dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset);
 833         ksmbd_debug(SMB,
 834                     "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n",
 835                     pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
 836                     le32_to_cpu(pntsd->gsidoffset),
 837                     le32_to_cpu(pntsd->sacloffset), dacloffset);
 838
 839         pntsd_type = le16_to_cpu(pntsd->type);
 840         if (!(pntsd_type & DACL_PRESENT)) {
 841                 ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n");
 842                 return rc;
 843         }
 844
 845         pntsd->type = cpu_to_le16(DACL_PRESENT);
 846
 847         if (pntsd->osidoffset) {
 848                 rc = parse_sid(owner_sid_ptr, end_of_acl);
 849                 if (rc) {
 850                         pr_err("%s: Error %d parsing Owner SID\n", __func__, rc);
 851                         return rc;
 852                 }
 853
 854                 rc = sid_to_id(idmap, owner_sid_ptr, SIDOWNER, fattr);
 855                 if (rc) {
 856                         pr_err("%s: Error %d mapping Owner SID to uid\n",
 857                                __func__, rc);
 858                         owner_sid_ptr = NULL;
 859                 }
 860         }
 861
 862         if (pntsd->gsidoffset) {
 863                 rc = parse_sid(group_sid_ptr, end_of_acl);
 864                 if (rc) {
 865                         pr_err("%s: Error %d mapping Owner SID to gid\n",
 866                                __func__, rc);
 867                         return rc;
 868                 }
 869                 rc = sid_to_id(idmap, group_sid_ptr, SIDUNIX_GROUP, fattr);
 870                 if (rc) {
 871                         pr_err("%s: Error %d mapping Group SID to gid\n",
 872                                __func__, rc);
 873                         group_sid_ptr = NULL;
 874                 }
 875         }
 876
 877         if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) ==
 878             (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ))
 879                 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
 880         if (pntsd_type & DACL_PROTECTED)
 881                 pntsd->type |= cpu_to_le16(DACL_PROTECTED);
 882
 883         if (dacloffset) {
 884                 parse_dacl(idmap, dacl_ptr, end_of_acl,
 885                            owner_sid_ptr, group_sid_ptr, fattr);
 886         }
 887
 888         return 0;
 889 }
 890
 891 /* Convert permission bits from mode to equivalent CIFS ACL */
 892 int build_sec_desc(struct mnt_idmap *idmap,
 893                    struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
 894                    int ppntsd_size, int addition_info, __u32 *secdesclen,
 895                    struct smb_fattr *fattr)
 896 {
 897         int rc = 0;
 898         __u32 offset;
 899         struct smb_sid *owner_sid_ptr, *group_sid_ptr;
 900         struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr;
 901         struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */
 902         uid_t uid;
 903         gid_t gid;
 904         unsigned int sid_type = SIDOWNER;
 905
 906         nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 907         if (!nowner_sid_ptr)
 908                 return -ENOMEM;
 909
 910         uid = from_kuid(&init_user_ns, fattr->cf_uid);
 911         if (!uid)
 912                 sid_type = SIDUNIX_USER;
 913         id_to_sid(uid, sid_type, nowner_sid_ptr);
 914
 915         ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
 916         if (!ngroup_sid_ptr) {
 917                 kfree(nowner_sid_ptr);
 918                 return -ENOMEM;
 919         }
 920
 921         gid = from_kgid(&init_user_ns, fattr->cf_gid);
 922         id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr);
 923
 924         offset = sizeof(struct smb_ntsd);
 925         pntsd->sacloffset = 0;
 926         pntsd->revision = cpu_to_le16(1);
 927         pntsd->type = cpu_to_le16(SELF_RELATIVE);
 928         if (ppntsd)
 929                 pntsd->type |= ppntsd->type;
 930
 931         if (addition_info & OWNER_SECINFO) {
 932                 pntsd->osidoffset = cpu_to_le32(offset);
 933                 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
 934                 smb_copy_sid(owner_sid_ptr, nowner_sid_ptr);
 935                 offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4);
 936         }
 937
 938         if (addition_info & GROUP_SECINFO) {
 939                 pntsd->gsidoffset = cpu_to_le32(offset);
 940                 group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
 941                 smb_copy_sid(group_sid_ptr, ngroup_sid_ptr);
 942                 offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4);
 943         }
 944
 945         if (addition_info & DACL_SECINFO) {
 946                 pntsd->type |= cpu_to_le16(DACL_PRESENT);
 947                 dacl_ptr = (struct smb_acl *)((char *)pntsd + offset);
 948                 dacl_ptr->revision = cpu_to_le16(2);
 949                 dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl));
 950                 dacl_ptr->num_aces = 0;
 951
 952                 if (!ppntsd) {
 953                         set_mode_dacl(idmap, dacl_ptr, fattr);
 954                 } else {
 955                         struct smb_acl *ppdacl_ptr;
 956                         unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset);
 957                         int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset;
 958
 959                         if (!dacl_offset ||
 960                             (dacl_offset + sizeof(struct smb_acl) > ppntsd_size))
 961                                 goto out;
 962
 963                         ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset);
 964                         ppdacl_size = le16_to_cpu(ppdacl_ptr->size);
 965                         if (ppdacl_size > ntacl_size ||
 966                             ppdacl_size < sizeof(struct smb_acl))
 967                                 goto out;
 968
 969                         set_ntacl_dacl(idmap, dacl_ptr, ppdacl_ptr,
 970                                        ntacl_size - sizeof(struct smb_acl),
 971                                        nowner_sid_ptr, ngroup_sid_ptr,
 972                                        fattr);
 973                 }
 974                 pntsd->dacloffset = cpu_to_le32(offset);
 975                 offset += le16_to_cpu(dacl_ptr->size);
 976         }
 977
 978 out:
 979         kfree(nowner_sid_ptr);
 980         kfree(ngroup_sid_ptr);
 981         *secdesclen = offset;
 982         return rc;
 983 }
 984
 985 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type,
 986                         u8 flags, __le32 access_req)
 987 {
 988         ace->type = type;
 989         ace->flags = flags;
 990         ace->access_req = access_req;
 991         smb_copy_sid(&ace->sid, sid);
 992         ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + (sid->num_subauth * 4));
 993 }
 994
 995 int smb_inherit_dacl(struct ksmbd_conn *conn,
 996                      const struct path *path,
 997                      unsigned int uid, unsigned int gid)
 998 {
 999         const struct smb_sid *psid, *creator = NULL;
1000         struct smb_ace *parent_aces, *aces;
1001         struct smb_acl *parent_pdacl;
1002         struct smb_ntsd *parent_pntsd = NULL;
1003         struct smb_sid owner_sid, group_sid;
1004         struct dentry *parent = path->dentry->d_parent;
1005         struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1006         int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size;
1007         int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size;
1008         char *aces_base;
1009         bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
1010
1011         pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1012                                             parent, &parent_pntsd);
1013         if (pntsd_size <= 0)
1014                 return -ENOENT;
1015         dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
1016         if (!dacloffset || (dacloffset + sizeof(struct smb_acl) > pntsd_size)) {
1017                 rc = -EINVAL;
1018                 goto free_parent_pntsd;
1019         }
1020
1021         parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset);
1022         acl_len = pntsd_size - dacloffset;
1023         num_aces = le32_to_cpu(parent_pdacl->num_aces);
1024         pntsd_type = le16_to_cpu(parent_pntsd->type);
1025         pdacl_size = le16_to_cpu(parent_pdacl->size);
1026
1027         if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) {
1028                 rc = -EINVAL;
1029                 goto free_parent_pntsd;
1030         }
1031
1032         aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL);
1033         if (!aces_base) {
1034                 rc = -ENOMEM;
1035                 goto free_parent_pntsd;
1036         }
1037
1038         aces = (struct smb_ace *)aces_base;
1039         parent_aces = (struct smb_ace *)((char *)parent_pdacl +
1040                         sizeof(struct smb_acl));
1041         aces_size = acl_len - sizeof(struct smb_acl);
1042
1043         if (pntsd_type & DACL_AUTO_INHERITED)
1044                 inherited_flags = INHERITED_ACE;
1045
1046         for (i = 0; i < num_aces; i++) {
1047                 int pace_size;
1048
1049                 if (offsetof(struct smb_ace, access_req) > aces_size)
1050                         break;
1051
1052                 pace_size = le16_to_cpu(parent_aces->size);
1053                 if (pace_size > aces_size)
1054                         break;
1055
1056                 aces_size -= pace_size;
1057
1058                 flags = parent_aces->flags;
1059                 if (!smb_inherit_flags(flags, is_dir))
1060                         goto pass;
1061                 if (is_dir) {
1062                         flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE);
1063                         if (!(flags & CONTAINER_INHERIT_ACE))
1064                                 flags |= INHERIT_ONLY_ACE;
1065                         if (flags & NO_PROPAGATE_INHERIT_ACE)
1066                                 flags = 0;
1067                 } else {
1068                         flags = 0;
1069                 }
1070
1071                 if (!compare_sids(&creator_owner, &parent_aces->sid)) {
1072                         creator = &creator_owner;
1073                         id_to_sid(uid, SIDOWNER, &owner_sid);
1074                         psid = &owner_sid;
1075                 } else if (!compare_sids(&creator_group, &parent_aces->sid)) {
1076                         creator = &creator_group;
1077                         id_to_sid(gid, SIDUNIX_GROUP, &group_sid);
1078                         psid = &group_sid;
1079                 } else {
1080                         creator = NULL;
1081                         psid = &parent_aces->sid;
1082                 }
1083
1084                 if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) {
1085                         smb_set_ace(aces, psid, parent_aces->type, inherited_flags,
1086                                     parent_aces->access_req);
1087                         nt_size += le16_to_cpu(aces->size);
1088                         ace_cnt++;
1089                         aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1090                         flags |= INHERIT_ONLY_ACE;
1091                         psid = creator;
1092                 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) {
1093                         psid = &parent_aces->sid;
1094                 }
1095
1096                 smb_set_ace(aces, psid, parent_aces->type, flags | inherited_flags,
1097                             parent_aces->access_req);
1098                 nt_size += le16_to_cpu(aces->size);
1099                 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1100                 ace_cnt++;
1101 pass:
1102                 parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size);
1103         }
1104
1105         if (nt_size > 0) {
1106                 struct smb_ntsd *pntsd;
1107                 struct smb_acl *pdacl;
1108                 struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL;
1109                 int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size;
1110
1111                 if (parent_pntsd->osidoffset) {
1112                         powner_sid = (struct smb_sid *)((char *)parent_pntsd +
1113                                         le32_to_cpu(parent_pntsd->osidoffset));
1114                         powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4);
1115                 }
1116                 if (parent_pntsd->gsidoffset) {
1117                         pgroup_sid = (struct smb_sid *)((char *)parent_pntsd +
1118                                         le32_to_cpu(parent_pntsd->gsidoffset));
1119                         pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4);
1120                 }
1121
1122                 pntsd = kzalloc(sizeof(struct smb_ntsd) + powner_sid_size +
1123                                 pgroup_sid_size + sizeof(struct smb_acl) +
1124                                 nt_size, GFP_KERNEL);
1125                 if (!pntsd) {
1126                         rc = -ENOMEM;
1127                         goto free_aces_base;
1128                 }
1129
1130                 pntsd->revision = cpu_to_le16(1);
1131                 pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT);
1132                 if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED)
1133                         pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
1134                 pntsd_size = sizeof(struct smb_ntsd);
1135                 pntsd->osidoffset = parent_pntsd->osidoffset;
1136                 pntsd->gsidoffset = parent_pntsd->gsidoffset;
1137                 pntsd->dacloffset = parent_pntsd->dacloffset;
1138
1139                 if (pntsd->osidoffset) {
1140                         struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd +
1141                                         le32_to_cpu(pntsd->osidoffset));
1142                         memcpy(owner_sid, powner_sid, powner_sid_size);
1143                         pntsd_size += powner_sid_size;
1144                 }
1145
1146                 if (pntsd->gsidoffset) {
1147                         struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd +
1148                                         le32_to_cpu(pntsd->gsidoffset));
1149                         memcpy(group_sid, pgroup_sid, pgroup_sid_size);
1150                         pntsd_size += pgroup_sid_size;
1151                 }
1152
1153                 if (pntsd->dacloffset) {
1154                         struct smb_ace *pace;
1155
1156                         pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1157                         pdacl->revision = cpu_to_le16(2);
1158                         pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size);
1159                         pdacl->num_aces = cpu_to_le32(ace_cnt);
1160                         pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1161                         memcpy(pace, aces_base, nt_size);
1162                         pntsd_size += sizeof(struct smb_acl) + nt_size;
1163                 }
1164
1165                 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, pntsd_size);
1166                 kfree(pntsd);
1167         }
1168
1169 free_aces_base:
1170         kfree(aces_base);
1171 free_parent_pntsd:
1172         kfree(parent_pntsd);
1173         return rc;
1174 }
1175
1176 bool smb_inherit_flags(int flags, bool is_dir)
1177 {
1178         if (!is_dir)
1179                 return (flags & OBJECT_INHERIT_ACE) != 0;
1180
1181         if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE))
1182                 return true;
1183
1184         if (flags & CONTAINER_INHERIT_ACE)
1185                 return true;
1186         return false;
1187 }
1188
1189 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
1190                         __le32 *pdaccess, int uid)
1191 {
1192         struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1193         struct smb_ntsd *pntsd = NULL;
1194         struct smb_acl *pdacl;
1195         struct posix_acl *posix_acls;
1196         int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size, dacl_offset;
1197         struct smb_sid sid;
1198         int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
1199         struct smb_ace *ace;
1200         int i, found = 0;
1201         unsigned int access_bits = 0;
1202         struct smb_ace *others_ace = NULL;
1203         struct posix_acl_entry *pa_entry;
1204         unsigned int sid_type = SIDOWNER;
1205         unsigned short ace_size;
1206
1207         ksmbd_debug(SMB, "check permission using windows acl\n");
1208         pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1209                                             path->dentry, &pntsd);
1210         if (pntsd_size <= 0 || !pntsd)
1211                 goto err_out;
1212
1213         dacl_offset = le32_to_cpu(pntsd->dacloffset);
1214         if (!dacl_offset ||
1215             (dacl_offset + sizeof(struct smb_acl) > pntsd_size))
1216                 goto err_out;
1217
1218         pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1219         acl_size = pntsd_size - dacl_offset;
1220         pdacl_size = le16_to_cpu(pdacl->size);
1221
1222         if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl))
1223                 goto err_out;
1224
1225         if (!pdacl->num_aces) {
1226                 if (!(pdacl_size - sizeof(struct smb_acl)) &&
1227                     *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) {
1228                         rc = -EACCES;
1229                         goto err_out;
1230                 }
1231                 goto err_out;
1232         }
1233
1234         if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
1235                 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1236                         DELETE;
1237
1238                 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1239                 aces_size = acl_size - sizeof(struct smb_acl);
1240                 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1241                         if (offsetof(struct smb_ace, access_req) > aces_size)
1242                                 break;
1243                         ace_size = le16_to_cpu(ace->size);
1244                         if (ace_size > aces_size)
1245                                 break;
1246                         aces_size -= ace_size;
1247                         granted |= le32_to_cpu(ace->access_req);
1248                         ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1249                 }
1250
1251                 if (!pdacl->num_aces)
1252                         granted = GENERIC_ALL_FLAGS;
1253         }
1254
1255         if (!uid)
1256                 sid_type = SIDUNIX_USER;
1257         id_to_sid(uid, sid_type, &sid);
1258
1259         ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1260         aces_size = acl_size - sizeof(struct smb_acl);
1261         for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1262                 if (offsetof(struct smb_ace, access_req) > aces_size)
1263                         break;
1264                 ace_size = le16_to_cpu(ace->size);
1265                 if (ace_size > aces_size)
1266                         break;
1267                 aces_size -= ace_size;
1268
1269                 if (!compare_sids(&sid, &ace->sid) ||
1270                     !compare_sids(&sid_unix_NFS_mode, &ace->sid)) {
1271                         found = 1;
1272                         break;
1273                 }
1274                 if (!compare_sids(&sid_everyone, &ace->sid))
1275                         others_ace = ace;
1276
1277                 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1278         }
1279
1280         if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
1281                 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1282                         DELETE;
1283
1284                 granted |= le32_to_cpu(ace->access_req);
1285
1286                 if (!pdacl->num_aces)
1287                         granted = GENERIC_ALL_FLAGS;
1288         }
1289
1290         if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
1291                 posix_acls = get_inode_acl(d_inode(path->dentry), ACL_TYPE_ACCESS);
1292                 if (!IS_ERR_OR_NULL(posix_acls) && !found) {
1293                         unsigned int id = -1;
1294
1295                         pa_entry = posix_acls->a_entries;
1296                         for (i = 0; i < posix_acls->a_count; i++, pa_entry++) {
1297                                 if (pa_entry->e_tag == ACL_USER)
1298                                         id = posix_acl_uid_translate(idmap, pa_entry);
1299                                 else if (pa_entry->e_tag == ACL_GROUP)
1300                                         id = posix_acl_gid_translate(idmap, pa_entry);
1301                                 else
1302                                         continue;
1303
1304                                 if (id == uid) {
1305                                         mode_to_access_flags(pa_entry->e_perm,
1306                                                              0777,
1307                                                              &access_bits);
1308                                         if (!access_bits)
1309                                                 access_bits =
1310                                                         SET_MINIMUM_RIGHTS;
1311                                         posix_acl_release(posix_acls);
1312                                         goto check_access_bits;
1313                                 }
1314                         }
1315                 }
1316                 if (!IS_ERR_OR_NULL(posix_acls))
1317                         posix_acl_release(posix_acls);
1318         }
1319
1320         if (!found) {
1321                 if (others_ace) {
1322                         ace = others_ace;
1323                 } else {
1324                         ksmbd_debug(SMB, "Can't find corresponding sid\n");
1325                         rc = -EACCES;
1326                         goto err_out;
1327                 }
1328         }
1329
1330         switch (ace->type) {
1331         case ACCESS_ALLOWED_ACE_TYPE:
1332                 access_bits = le32_to_cpu(ace->access_req);
1333                 break;
1334         case ACCESS_DENIED_ACE_TYPE:
1335         case ACCESS_DENIED_CALLBACK_ACE_TYPE:
1336                 access_bits = le32_to_cpu(~ace->access_req);
1337                 break;
1338         }
1339
1340 check_access_bits:
1341         if (granted &
1342             ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) {
1343                 ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n",
1344                             granted, le32_to_cpu(ace->access_req));
1345                 rc = -EACCES;
1346                 goto err_out;
1347         }
1348
1349         *pdaccess = cpu_to_le32(granted);
1350 err_out:
1351         kfree(pntsd);
1352         return rc;
1353 }
1354
1355 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
1356                  const struct path *path, struct smb_ntsd *pntsd, int ntsd_len,
1357                  bool type_check)
1358 {
1359         int rc;
1360         struct smb_fattr fattr = {{0}};
1361         struct inode *inode = d_inode(path->dentry);
1362         struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1363         struct iattr newattrs;
1364
1365         fattr.cf_uid = INVALID_UID;
1366         fattr.cf_gid = INVALID_GID;
1367         fattr.cf_mode = inode->i_mode;
1368
1369         rc = parse_sec_desc(idmap, pntsd, ntsd_len, &fattr);
1370         if (rc)
1371                 goto out;
1372
1373         newattrs.ia_valid = ATTR_CTIME;
1374         if (!uid_eq(fattr.cf_uid, INVALID_UID)) {
1375                 newattrs.ia_valid |= ATTR_UID;
1376                 newattrs.ia_uid = fattr.cf_uid;
1377         }
1378         if (!gid_eq(fattr.cf_gid, INVALID_GID)) {
1379                 newattrs.ia_valid |= ATTR_GID;
1380                 newattrs.ia_gid = fattr.cf_gid;
1381         }
1382         newattrs.ia_valid |= ATTR_MODE;
1383         newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
1384
1385         ksmbd_vfs_remove_acl_xattrs(idmap, path);
1386         /* Update posix acls */
1387         if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) {
1388                 rc = set_posix_acl(idmap, path->dentry,
1389                                    ACL_TYPE_ACCESS, fattr.cf_acls);
1390                 if (rc < 0)
1391                         ksmbd_debug(SMB,
1392                                     "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
1393                                     rc);
1394                 if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) {
1395                         rc = set_posix_acl(idmap, path->dentry,
1396                                            ACL_TYPE_DEFAULT, fattr.cf_dacls);
1397                         if (rc)
1398                                 ksmbd_debug(SMB,
1399                                             "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n",
1400                                             rc);
1401                 }
1402         }
1403
1404         inode_lock(inode);
1405         rc = notify_change(idmap, path->dentry, &newattrs, NULL);
1406         inode_unlock(inode);
1407         if (rc)
1408                 goto out;
1409
1410         /* Check it only calling from SD BUFFER context */
1411         if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT))
1412                 goto out;
1413
1414         if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) {
1415                 /* Update WinACL in xattr */
1416                 ksmbd_vfs_remove_sd_xattrs(idmap, path);
1417                 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, ntsd_len);
1418         }
1419
1420 out:
1421         posix_acl_release(fattr.cf_acls);
1422         posix_acl_release(fattr.cf_dacls);
1423         mark_inode_dirty(inode);
1424         return rc;
1425 }
1426
1427 void ksmbd_init_domain(u32 *sub_auth)
1428 {
1429         int i;
1430
1431         memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid));
1432         for (i = 0; i < 3; ++i)
1433                 server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]);
1434 }