source3/modules/vfs_acl_common.c

   1 /*
   2  * Store Windows ACLs in data store - common functions.
   3  * #included into modules/vfs_acl_xattr.c and modules/vfs_acl_tdb.c
   4  *
   5  * Copyright (C) Volker Lendecke, 2008
   6  * Copyright (C) Jeremy Allison, 2009
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 3 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include "smbd/smbd.h"
  23 #include "system/filesys.h"
  24 #include "../libcli/security/security.h"
  25 #include "../librpc/gen_ndr/ndr_security.h"
  26 #include "../lib/util/bitmap.h"
  27
  28 static NTSTATUS create_acl_blob(const struct security_descriptor *psd,
  29                         DATA_BLOB *pblob,
  30                         uint16_t hash_type,
  31                         uint8_t hash[XATTR_SD_HASH_SIZE]);
  32
  33 static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
  34                         vfs_handle_struct *handle,
  35                         files_struct *fsp,
  36                         const char *name,
  37                         DATA_BLOB *pblob);
  38
  39 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
  40                         files_struct *fsp,
  41                         DATA_BLOB *pblob);
  42
  43 #define HASH_SECURITY_INFO (SECINFO_OWNER | \
  44                                 SECINFO_GROUP | \
  45                                 SECINFO_DACL | \
  46                                 SECINFO_SACL)
  47
  48 /*******************************************************************
  49  Hash a security descriptor.
  50 *******************************************************************/
  51
  52 static NTSTATUS hash_sd_sha256(struct security_descriptor *psd,
  53                         uint8_t *hash)
  54 {
  55         DATA_BLOB blob;
  56         SHA256_CTX tctx;
  57         NTSTATUS status;
  58
  59         memset(hash, '\0', XATTR_SD_HASH_SIZE);
  60         status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
  61         if (!NT_STATUS_IS_OK(status)) {
  62                 return status;
  63         }
  64
  65         samba_SHA256_Init(&tctx);
  66         samba_SHA256_Update(&tctx, blob.data, blob.length);
  67         samba_SHA256_Final(hash, &tctx);
  68
  69         return NT_STATUS_OK;
  70 }
  71
  72 /*******************************************************************
  73  Parse out a struct security_descriptor from a DATA_BLOB.
  74 *******************************************************************/
  75
  76 static NTSTATUS parse_acl_blob(const DATA_BLOB *pblob,
  77                                TALLOC_CTX *mem_ctx,
  78                                 struct security_descriptor **ppdesc,
  79                                 uint16_t *p_hash_type,
  80                                 uint8_t hash[XATTR_SD_HASH_SIZE])
  81 {
  82         struct xattr_NTACL xacl;
  83         enum ndr_err_code ndr_err;
  84         size_t sd_size;
  85         TALLOC_CTX *frame = talloc_stackframe();
  86
  87         ndr_err = ndr_pull_struct_blob(pblob, frame, &xacl,
  88                         (ndr_pull_flags_fn_t)ndr_pull_xattr_NTACL);
  89
  90         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
  91                 DEBUG(5, ("parse_acl_blob: ndr_pull_xattr_NTACL failed: %s\n",
  92                         ndr_errstr(ndr_err)));
  93                 TALLOC_FREE(frame);
  94                 return ndr_map_error2ntstatus(ndr_err);
  95         }
  96
  97         switch (xacl.version) {
  98                 case 1:
  99                         *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
 100                                         xacl.info.sd->type | SEC_DESC_SELF_RELATIVE,
 101                                         xacl.info.sd->owner_sid,
 102                                         xacl.info.sd->group_sid,
 103                                         xacl.info.sd->sacl,
 104                                         xacl.info.sd->dacl,
 105                                         &sd_size);
 106                         /* No hash - null out. */
 107                         *p_hash_type = XATTR_SD_HASH_TYPE_NONE;
 108                         memset(hash, '\0', XATTR_SD_HASH_SIZE);
 109                         break;
 110                 case 2:
 111                         *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
 112                                         xacl.info.sd_hs2->sd->type | SEC_DESC_SELF_RELATIVE,
 113                                         xacl.info.sd_hs2->sd->owner_sid,
 114                                         xacl.info.sd_hs2->sd->group_sid,
 115                                         xacl.info.sd_hs2->sd->sacl,
 116                                         xacl.info.sd_hs2->sd->dacl,
 117                                         &sd_size);
 118                         /* No hash - null out. */
 119                         *p_hash_type = XATTR_SD_HASH_TYPE_NONE;
 120                         memset(hash, '\0', XATTR_SD_HASH_SIZE);
 121                         break;
 122                 case 3:
 123                         *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
 124                                         xacl.info.sd_hs3->sd->type | SEC_DESC_SELF_RELATIVE,
 125                                         xacl.info.sd_hs3->sd->owner_sid,
 126                                         xacl.info.sd_hs3->sd->group_sid,
 127                                         xacl.info.sd_hs3->sd->sacl,
 128                                         xacl.info.sd_hs3->sd->dacl,
 129                                         &sd_size);
 130                         *p_hash_type = xacl.info.sd_hs3->hash_type;
 131                         /* Current version 3. */
 132                         memcpy(hash, xacl.info.sd_hs3->hash, XATTR_SD_HASH_SIZE);
 133                         break;
 134                 default:
 135                         TALLOC_FREE(frame);
 136                         return NT_STATUS_REVISION_MISMATCH;
 137         }
 138
 139         TALLOC_FREE(frame);
 140
 141         return (*ppdesc != NULL) ? NT_STATUS_OK : NT_STATUS_NO_MEMORY;
 142 }
 143
 144 /*******************************************************************
 145  Create a DATA_BLOB from a security descriptor.
 146 *******************************************************************/
 147
 148 static NTSTATUS create_acl_blob(const struct security_descriptor *psd,
 149                         DATA_BLOB *pblob,
 150                         uint16_t hash_type,
 151                         uint8_t hash[XATTR_SD_HASH_SIZE])
 152 {
 153         struct xattr_NTACL xacl;
 154         struct security_descriptor_hash_v3 sd_hs3;
 155         enum ndr_err_code ndr_err;
 156         TALLOC_CTX *ctx = talloc_tos();
 157
 158         ZERO_STRUCT(xacl);
 159         ZERO_STRUCT(sd_hs3);
 160
 161         xacl.version = 3;
 162         xacl.info.sd_hs3 = &sd_hs3;
 163         xacl.info.sd_hs3->sd = discard_const_p(struct security_descriptor, psd);
 164         xacl.info.sd_hs3->hash_type = hash_type;
 165         memcpy(&xacl.info.sd_hs3->hash[0], hash, XATTR_SD_HASH_SIZE);
 166
 167         ndr_err = ndr_push_struct_blob(
 168                         pblob, ctx, &xacl,
 169                         (ndr_push_flags_fn_t)ndr_push_xattr_NTACL);
 170
 171         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 172                 DEBUG(5, ("create_acl_blob: ndr_push_xattr_NTACL failed: %s\n",
 173                         ndr_errstr(ndr_err)));
 174                 return ndr_map_error2ntstatus(ndr_err);
 175         }
 176
 177         return NT_STATUS_OK;
 178 }
 179
 180 /*******************************************************************
 181  Add in 3 inheritable components for a non-inheritable directory ACL.
 182  CREATOR_OWNER/CREATOR_GROUP/WORLD.
 183 *******************************************************************/
 184
 185 static NTSTATUS add_directory_inheritable_components(vfs_handle_struct *handle,
 186                                 const char *name,
 187                                 SMB_STRUCT_STAT *psbuf,
 188                                 struct security_descriptor *psd)
 189 {
 190         struct connection_struct *conn = handle->conn;
 191         int num_aces = (psd->dacl ? psd->dacl->num_aces : 0);
 192         struct smb_filename smb_fname;
 193         enum security_ace_type acltype;
 194         uint32_t access_mask;
 195         mode_t dir_mode;
 196         mode_t file_mode;
 197         mode_t mode;
 198         struct security_ace *new_ace_list = talloc_zero_array(talloc_tos(),
 199                                                 struct security_ace,
 200                                                 num_aces + 3);
 201
 202         if (new_ace_list == NULL) {
 203                 return NT_STATUS_NO_MEMORY;
 204         }
 205
 206         /* Fake a quick smb_filename. */
 207         ZERO_STRUCT(smb_fname);
 208         smb_fname.st = *psbuf;
 209         smb_fname.base_name = discard_const_p(char, name);
 210
 211         dir_mode = unix_mode(conn,
 212                         FILE_ATTRIBUTE_DIRECTORY, &smb_fname, NULL);
 213         file_mode = unix_mode(conn,
 214                         FILE_ATTRIBUTE_ARCHIVE, &smb_fname, NULL);
 215
 216         mode = dir_mode | file_mode;
 217
 218         DEBUG(10, ("add_directory_inheritable_components: directory %s, "
 219                 "mode = 0%o\n",
 220                 name,
 221                 (unsigned int)mode ));
 222
 223         if (num_aces) {
 224                 memcpy(new_ace_list, psd->dacl->aces,
 225                         num_aces * sizeof(struct security_ace));
 226         }
 227         access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
 228                                 mode & 0700, false);
 229
 230         init_sec_ace(&new_ace_list[num_aces],
 231                         &global_sid_Creator_Owner,
 232                         acltype,
 233                         access_mask,
 234                         SEC_ACE_FLAG_CONTAINER_INHERIT|
 235                                 SEC_ACE_FLAG_OBJECT_INHERIT|
 236                                 SEC_ACE_FLAG_INHERIT_ONLY);
 237         access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
 238                                 (mode << 3) & 0700, false);
 239         init_sec_ace(&new_ace_list[num_aces+1],
 240                         &global_sid_Creator_Group,
 241                         acltype,
 242                         access_mask,
 243                         SEC_ACE_FLAG_CONTAINER_INHERIT|
 244                                 SEC_ACE_FLAG_OBJECT_INHERIT|
 245                                 SEC_ACE_FLAG_INHERIT_ONLY);
 246         access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
 247                                 (mode << 6) & 0700, false);
 248         init_sec_ace(&new_ace_list[num_aces+2],
 249                         &global_sid_World,
 250                         acltype,
 251                         access_mask,
 252                         SEC_ACE_FLAG_CONTAINER_INHERIT|
 253                                 SEC_ACE_FLAG_OBJECT_INHERIT|
 254                                 SEC_ACE_FLAG_INHERIT_ONLY);
 255         if (psd->dacl) {
 256                 psd->dacl->aces = new_ace_list;
 257                 psd->dacl->num_aces += 3;
 258         } else {
 259                 psd->dacl = make_sec_acl(talloc_tos(),
 260                                 NT4_ACL_REVISION,
 261                                 3,
 262                                 new_ace_list);
 263                 if (psd->dacl == NULL) {
 264                         return NT_STATUS_NO_MEMORY;
 265                 }
 266         }
 267         return NT_STATUS_OK;
 268 }
 269
 270 /*******************************************************************
 271  Pull a DATA_BLOB from an xattr given a pathname.
 272  If the hash doesn't match, or doesn't exist - return the underlying
 273  filesystem sd.
 274 *******************************************************************/
 275
 276 static NTSTATUS get_nt_acl_internal(vfs_handle_struct *handle,
 277                                 files_struct *fsp,
 278                                 const char *name,
 279                                 uint32_t security_info,
 280                                 TALLOC_CTX *mem_ctx,
 281                                     struct security_descriptor **ppdesc)
 282 {
 283         DATA_BLOB blob = data_blob_null;
 284         NTSTATUS status;
 285         uint16_t hash_type = XATTR_SD_HASH_TYPE_NONE;
 286         uint8_t hash[XATTR_SD_HASH_SIZE];
 287         uint8_t hash_tmp[XATTR_SD_HASH_SIZE];
 288         struct security_descriptor *psd = NULL;
 289         struct security_descriptor *pdesc_next = NULL;
 290         bool ignore_file_system_acl = lp_parm_bool(SNUM(handle->conn),
 291                                                 ACL_MODULE_NAME,
 292                                                 "ignore system acls",
 293                                                 false);
 294
 295         if (fsp && name == NULL) {
 296                 name = fsp->fsp_name->base_name;
 297         }
 298
 299         DEBUG(10, ("get_nt_acl_internal: name=%s\n", name));
 300
 301         /* Get the full underlying sd for the hash
 302            or to return as backup. */
 303         if (fsp) {
 304                 status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
 305                                                   fsp,
 306                                                   HASH_SECURITY_INFO,
 307                                                   mem_ctx,
 308                                                   &pdesc_next);
 309         } else {
 310                 status = SMB_VFS_NEXT_GET_NT_ACL(handle,
 311                                                  name,
 312                                                  HASH_SECURITY_INFO,
 313                                                  mem_ctx,
 314                                                  &pdesc_next);
 315         }
 316
 317         if (!NT_STATUS_IS_OK(status)) {
 318                 DEBUG(10, ("get_nt_acl_internal: get_next_acl for file %s "
 319                         "returned %s\n",
 320                         name,
 321                         nt_errstr(status)));
 322                 return status;
 323         }
 324
 325         status = get_acl_blob(talloc_tos(), handle, fsp, name, &blob);
 326         if (!NT_STATUS_IS_OK(status)) {
 327                 DEBUG(10, ("get_nt_acl_internal: get_acl_blob returned %s\n",
 328                         nt_errstr(status)));
 329                 psd = pdesc_next;
 330                 goto out;
 331         }
 332
 333         status = parse_acl_blob(&blob, mem_ctx, &psd,
 334                                 &hash_type, &hash[0]);
 335         if (!NT_STATUS_IS_OK(status)) {
 336                 DEBUG(10, ("parse_acl_blob returned %s\n",
 337                                 nt_errstr(status)));
 338                 psd = pdesc_next;
 339                 goto out;
 340         }
 341
 342         /* Ensure the hash type is one we know. */
 343         switch (hash_type) {
 344                 case XATTR_SD_HASH_TYPE_NONE:
 345                         /* No hash, just return blob sd. */
 346                         goto out;
 347                 case XATTR_SD_HASH_TYPE_SHA256:
 348                         break;
 349                 default:
 350                         DEBUG(10, ("get_nt_acl_internal: ACL blob revision "
 351                                 "mismatch (%u) for file %s\n",
 352                                 (unsigned int)hash_type,
 353                                 name));
 354                         TALLOC_FREE(psd);
 355                         psd = pdesc_next;
 356                         goto out;
 357         }
 358
 359         if (ignore_file_system_acl) {
 360                 goto out;
 361         }
 362
 363         status = hash_sd_sha256(pdesc_next, hash_tmp);
 364         if (!NT_STATUS_IS_OK(status)) {
 365                 TALLOC_FREE(psd);
 366                 psd = pdesc_next;
 367                 goto out;
 368         }
 369
 370         if (memcmp(&hash[0], &hash_tmp[0], XATTR_SD_HASH_SIZE) == 0) {
 371                 /* Hash matches, return blob sd. */
 372                 DEBUG(10, ("get_nt_acl_internal: blob hash "
 373                         "matches for file %s\n",
 374                         name ));
 375                 goto out;
 376         }
 377
 378         /* Hash doesn't match, return underlying sd. */
 379         DEBUG(10, ("get_nt_acl_internal: blob hash "
 380                 "does not match for file %s - returning "
 381                 "file system SD mapping.\n",
 382                 name ));
 383
 384         if (DEBUGLEVEL >= 10) {
 385                 DEBUG(10,("get_nt_acl_internal: acl for blob hash for %s is:\n",
 386                         name ));
 387                 NDR_PRINT_DEBUG(security_descriptor, pdesc_next);
 388         }
 389
 390         TALLOC_FREE(psd);
 391         psd = pdesc_next;
 392
 393   out:
 394
 395         if (psd != pdesc_next) {
 396                 /* We're returning the blob, throw
 397                  * away the filesystem SD. */
 398                 TALLOC_FREE(pdesc_next);
 399         } else {
 400                 SMB_STRUCT_STAT sbuf;
 401                 SMB_STRUCT_STAT *psbuf = &sbuf;
 402                 bool is_directory = false;
 403                 /*
 404                  * We're returning the underlying ACL from the
 405                  * filesystem. If it's a directory, and has no
 406                  * inheritable ACE entries we have to fake them.
 407                  */
 408                 if (fsp) {
 409                         status = vfs_stat_fsp(fsp);
 410                         if (!NT_STATUS_IS_OK(status)) {
 411                                 return status;
 412                         }
 413                         psbuf = &fsp->fsp_name->st;
 414                 } else {
 415                         int ret = vfs_stat_smb_fname(handle->conn,
 416                                                 name,
 417                                                 &sbuf);
 418                         if (ret == -1) {
 419                                 return map_nt_error_from_unix(errno);
 420                         }
 421                 }
 422                 is_directory = S_ISDIR(psbuf->st_ex_mode);
 423
 424                 if (ignore_file_system_acl) {
 425                         TALLOC_FREE(pdesc_next);
 426                         status = make_default_filesystem_acl(mem_ctx,
 427                                                 name,
 428                                                 psbuf,
 429                                                 &psd);
 430                         if (!NT_STATUS_IS_OK(status)) {
 431                                 return status;
 432                         }
 433                 } else {
 434                         if (is_directory &&
 435                                 !sd_has_inheritable_components(psd,
 436                                                         true)) {
 437                                 status = add_directory_inheritable_components(
 438                                                         handle,
 439                                                         name,
 440                                                         psbuf,
 441                                                         psd);
 442                                 if (!NT_STATUS_IS_OK(status)) {
 443                                         return status;
 444                                 }
 445                         }
 446                         /* The underlying POSIX module always sets
 447                            the ~SEC_DESC_DACL_PROTECTED bit, as ACLs
 448                            can't be inherited in this way under POSIX.
 449                            Remove it for Windows-style ACLs. */
 450                         psd->type &= ~SEC_DESC_DACL_PROTECTED;
 451                 }
 452         }
 453
 454         if (!(security_info & SECINFO_OWNER)) {
 455                 psd->owner_sid = NULL;
 456         }
 457         if (!(security_info & SECINFO_GROUP)) {
 458                 psd->group_sid = NULL;
 459         }
 460         if (!(security_info & SECINFO_DACL)) {
 461                 psd->type &= ~SEC_DESC_DACL_PRESENT;
 462                 psd->dacl = NULL;
 463         }
 464         if (!(security_info & SECINFO_SACL)) {
 465                 psd->type &= ~SEC_DESC_SACL_PRESENT;
 466                 psd->sacl = NULL;
 467         }
 468
 469         TALLOC_FREE(blob.data);
 470         *ppdesc = psd;
 471
 472         if (DEBUGLEVEL >= 10) {
 473                 DEBUG(10,("get_nt_acl_internal: returning acl for %s is:\n",
 474                         name ));
 475                 NDR_PRINT_DEBUG(security_descriptor, psd);
 476         }
 477
 478         return NT_STATUS_OK;
 479 }
 480
 481 /*********************************************************************
 482  Fetch a security descriptor given an fsp.
 483 *********************************************************************/
 484
 485 static NTSTATUS fget_nt_acl_common(vfs_handle_struct *handle,
 486                                    files_struct *fsp,
 487                                    uint32_t security_info,
 488                                    TALLOC_CTX *mem_ctx,
 489                                    struct security_descriptor **ppdesc)
 490 {
 491         return get_nt_acl_internal(handle, fsp,
 492                                    NULL, security_info, mem_ctx, ppdesc);
 493 }
 494
 495 /*********************************************************************
 496  Fetch a security descriptor given a pathname.
 497 *********************************************************************/
 498
 499 static NTSTATUS get_nt_acl_common(vfs_handle_struct *handle,
 500                                   const char *name,
 501                                   uint32_t security_info,
 502                                   TALLOC_CTX *mem_ctx,
 503                                   struct security_descriptor **ppdesc)
 504 {
 505         return get_nt_acl_internal(handle, NULL,
 506                                    name, security_info, mem_ctx, ppdesc);
 507 }
 508
 509 /*********************************************************************
 510  Store a security descriptor given an fsp.
 511 *********************************************************************/
 512
 513 static NTSTATUS fset_nt_acl_common(vfs_handle_struct *handle, files_struct *fsp,
 514         uint32_t security_info_sent, const struct security_descriptor *orig_psd)
 515 {
 516         NTSTATUS status;
 517         DATA_BLOB blob;
 518         struct security_descriptor *pdesc_next = NULL;
 519         struct security_descriptor *psd = NULL;
 520         uint8_t hash[XATTR_SD_HASH_SIZE];
 521         bool chown_needed = false;
 522         TALLOC_CTX *frame = talloc_stackframe();
 523
 524         if (DEBUGLEVEL >= 10) {
 525                 DEBUG(10,("fset_nt_acl_xattr: incoming sd for file %s\n",
 526                           fsp_str_dbg(fsp)));
 527                 NDR_PRINT_DEBUG(security_descriptor,
 528                         discard_const_p(struct security_descriptor, orig_psd));
 529         }
 530
 531         status = get_nt_acl_internal(handle, fsp,
 532                         NULL,
 533                         SECINFO_OWNER|SECINFO_GROUP|SECINFO_DACL|SECINFO_SACL,
 534                                      frame,
 535                         &psd);
 536
 537         if (!NT_STATUS_IS_OK(status)) {
 538                 TALLOC_FREE(frame);
 539                 return status;
 540         }
 541
 542         psd->revision = orig_psd->revision;
 543         /* All our SD's are self relative. */
 544         psd->type = orig_psd->type | SEC_DESC_SELF_RELATIVE;
 545
 546         if ((security_info_sent & SECINFO_OWNER) && (orig_psd->owner_sid != NULL)) {
 547                 if (!dom_sid_equal(orig_psd->owner_sid, psd->owner_sid)) {
 548                         /* We're changing the owner. */
 549                         chown_needed = true;
 550                 }
 551                 psd->owner_sid = orig_psd->owner_sid;
 552         }
 553         if ((security_info_sent & SECINFO_GROUP) && (orig_psd->group_sid != NULL)) {
 554                 if (!dom_sid_equal(orig_psd->group_sid, psd->group_sid)) {
 555                         /* We're changing the group. */
 556                         chown_needed = true;
 557                 }
 558                 psd->group_sid = orig_psd->group_sid;
 559         }
 560         if (security_info_sent & SECINFO_DACL) {
 561                 psd->dacl = orig_psd->dacl;
 562                 psd->type |= SEC_DESC_DACL_PRESENT;
 563         }
 564         if (security_info_sent & SECINFO_SACL) {
 565                 psd->sacl = orig_psd->sacl;
 566                 psd->type |= SEC_DESC_SACL_PRESENT;
 567         }
 568
 569         status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
 570         if (!NT_STATUS_IS_OK(status)) {
 571                 if (!NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED)) {
 572                         TALLOC_FREE(frame);
 573                         return status;
 574                 }
 575                 /* We got access denied here. If we're already root,
 576                    or we didn't need to do a chown, or the fsp isn't
 577                    open with WRITE_OWNER access, just return. */
 578                 if (get_current_uid(handle->conn) == 0 ||
 579                                 chown_needed == false ||
 580                                 !(fsp->access_mask & SEC_STD_WRITE_OWNER)) {
 581                         return NT_STATUS_ACCESS_DENIED;
 582                 }
 583
 584                 DEBUG(10,("fset_nt_acl_common: overriding chown on file %s "
 585                         "for sid %s\n",
 586                         fsp_str_dbg(fsp),
 587                         sid_string_tos(psd->owner_sid)
 588                         ));
 589
 590                 /* Ok, we failed to chown and we have
 591                    SEC_STD_WRITE_OWNER access - override. */
 592                 become_root();
 593                 status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp,
 594                                 security_info_sent, psd);
 595                 unbecome_root();
 596                 if (!NT_STATUS_IS_OK(status)) {
 597                         TALLOC_FREE(frame);
 598                         return status;
 599                 }
 600         }
 601
 602         /* Get the full underlying sd, then hash. */
 603         status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
 604                                           fsp,
 605                                           HASH_SECURITY_INFO,
 606                                           frame,
 607                                           &pdesc_next);
 608
 609         if (!NT_STATUS_IS_OK(status)) {
 610                 TALLOC_FREE(frame);
 611                 return status;
 612         }
 613
 614         status = hash_sd_sha256(pdesc_next, hash);
 615         if (!NT_STATUS_IS_OK(status)) {
 616                 TALLOC_FREE(frame);
 617                 return status;
 618         }
 619
 620         if (DEBUGLEVEL >= 10) {
 621                 DEBUG(10,("fset_nt_acl_xattr: storing xattr sd for file %s\n",
 622                           fsp_str_dbg(fsp)));
 623                 NDR_PRINT_DEBUG(security_descriptor,
 624                         discard_const_p(struct security_descriptor, psd));
 625
 626                 DEBUG(10,("fset_nt_acl_xattr: storing has in xattr sd based on \n"));
 627                 NDR_PRINT_DEBUG(security_descriptor,
 628                         discard_const_p(struct security_descriptor, pdesc_next));
 629         }
 630         status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
 631         if (!NT_STATUS_IS_OK(status)) {
 632                 DEBUG(10, ("fset_nt_acl_xattr: create_acl_blob failed\n"));
 633                 TALLOC_FREE(frame);
 634                 return status;
 635         }
 636
 637         status = store_acl_blob_fsp(handle, fsp, &blob);
 638
 639         TALLOC_FREE(frame);
 640         return status;
 641 }
 642
 643 static int acl_common_remove_object(vfs_handle_struct *handle,
 644                                         const char *path,
 645                                         bool is_directory)
 646 {
 647         connection_struct *conn = handle->conn;
 648         struct file_id id;
 649         files_struct *fsp = NULL;
 650         int ret = 0;
 651         char *parent_dir = NULL;
 652         const char *final_component = NULL;
 653         struct smb_filename local_fname;
 654         int saved_errno = 0;
 655         char *saved_dir = NULL;
 656
 657         saved_dir = vfs_GetWd(talloc_tos(),conn);
 658         if (!saved_dir) {
 659                 saved_errno = errno;
 660                 goto out;
 661         }
 662
 663         if (!parent_dirname(talloc_tos(), path,
 664                         &parent_dir, &final_component)) {
 665                 saved_errno = ENOMEM;
 666                 goto out;
 667         }
 668
 669         DEBUG(10,("acl_common_remove_object: removing %s %s/%s\n",
 670                 is_directory ? "directory" : "file",
 671                 parent_dir, final_component ));
 672
 673         /* cd into the parent dir to pin it. */
 674         ret = vfs_ChDir(conn, parent_dir);
 675         if (ret == -1) {
 676                 saved_errno = errno;
 677                 goto out;
 678         }
 679
 680         ZERO_STRUCT(local_fname);
 681         local_fname.base_name = discard_const_p(char, final_component);
 682
 683         /* Must use lstat here. */
 684         ret = SMB_VFS_LSTAT(conn, &local_fname);
 685         if (ret == -1) {
 686                 saved_errno = errno;
 687                 goto out;
 688         }
 689
 690         /* Ensure we have this file open with DELETE access. */
 691         id = vfs_file_id_from_sbuf(conn, &local_fname.st);
 692         for (fsp = file_find_di_first(conn->sconn, id); fsp;
 693                      fsp = file_find_di_next(fsp)) {
 694                 if (fsp->access_mask & DELETE_ACCESS &&
 695                                 fsp->delete_on_close) {
 696                         /* We did open this for delete,
 697                          * allow the delete as root.
 698                          */
 699                         break;
 700                 }
 701         }
 702
 703         if (!fsp) {
 704                 DEBUG(10,("acl_common_remove_object: %s %s/%s "
 705                         "not an open file\n",
 706                         is_directory ? "directory" : "file",
 707                         parent_dir, final_component ));
 708                 saved_errno = EACCES;
 709                 goto out;
 710         }
 711
 712         become_root();
 713         if (is_directory) {
 714                 ret = SMB_VFS_NEXT_RMDIR(handle, final_component);
 715         } else {
 716                 ret = SMB_VFS_NEXT_UNLINK(handle, &local_fname);
 717         }
 718         unbecome_root();
 719
 720         if (ret == -1) {
 721                 saved_errno = errno;
 722         }
 723
 724   out:
 725
 726         TALLOC_FREE(parent_dir);
 727
 728         if (saved_dir) {
 729                 vfs_ChDir(conn, saved_dir);
 730         }
 731         if (saved_errno) {
 732                 errno = saved_errno;
 733         }
 734         return ret;
 735 }
 736
 737 static int rmdir_acl_common(struct vfs_handle_struct *handle,
 738                                 const char *path)
 739 {
 740         int ret;
 741
 742         /* Try the normal rmdir first. */
 743         ret = SMB_VFS_NEXT_RMDIR(handle, path);
 744         if (ret == 0) {
 745                 return 0;
 746         }
 747         if (errno == EACCES || errno == EPERM) {
 748                 /* Failed due to access denied,
 749                    see if we need to root override. */
 750                 return acl_common_remove_object(handle,
 751                                                 path,
 752                                                 true);
 753         }
 754
 755         DEBUG(10,("rmdir_acl_common: unlink of %s failed %s\n",
 756                 path,
 757                 strerror(errno) ));
 758         return -1;
 759 }
 760
 761 static int unlink_acl_common(struct vfs_handle_struct *handle,
 762                         const struct smb_filename *smb_fname)
 763 {
 764         int ret;
 765
 766         /* Try the normal unlink first. */
 767         ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname);
 768         if (ret == 0) {
 769                 return 0;
 770         }
 771         if (errno == EACCES || errno == EPERM) {
 772                 /* Failed due to access denied,
 773                    see if we need to root override. */
 774
 775                 /* Don't do anything fancy for streams. */
 776                 if (smb_fname->stream_name) {
 777                         return -1;
 778                 }
 779                 return acl_common_remove_object(handle,
 780                                         smb_fname->base_name,
 781                                         false);
 782         }
 783
 784         DEBUG(10,("unlink_acl_common: unlink of %s failed %s\n",
 785                 smb_fname->base_name,
 786                 strerror(errno) ));
 787         return -1;
 788 }
 789
 790 static int chmod_acl_module_common(struct vfs_handle_struct *handle,
 791                         const char *path, mode_t mode)
 792 {
 793         if (lp_posix_pathnames()) {
 794                 /* Only allow this on POSIX pathnames. */
 795                 return SMB_VFS_NEXT_CHMOD(handle, path, mode);
 796         }
 797         return 0;
 798 }
 799
 800 static int fchmod_acl_module_common(struct vfs_handle_struct *handle,
 801                         struct files_struct *fsp, mode_t mode)
 802 {
 803         if (fsp->posix_open) {
 804                 /* Only allow this on POSIX opens. */
 805                 return SMB_VFS_NEXT_FCHMOD(handle, fsp, mode);
 806         }
 807         return 0;
 808 }
 809
 810 static int chmod_acl_acl_module_common(struct vfs_handle_struct *handle,
 811                         const char *name, mode_t mode)
 812 {
 813         if (lp_posix_pathnames()) {
 814                 /* Only allow this on POSIX pathnames. */
 815                 return SMB_VFS_NEXT_CHMOD_ACL(handle, name, mode);
 816         }
 817         return 0;
 818 }
 819
 820 static int fchmod_acl_acl_module_common(struct vfs_handle_struct *handle,
 821                         struct files_struct *fsp, mode_t mode)
 822 {
 823         if (fsp->posix_open) {
 824                 /* Only allow this on POSIX opens. */
 825                 return SMB_VFS_NEXT_FCHMOD_ACL(handle, fsp, mode);
 826         }
 827         return 0;
 828 }