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;
 199
 200         if (psd->dacl) {
 201                 new_ace_list = talloc_zero_array(psd->dacl,
 202                                                  struct security_ace,
 203                                                  num_aces + 3);
 204         } else {
 205                 /*
 206                  * make_sec_acl() at the bottom of this function
 207                  * dupliates new_ace_list
 208                  */
 209                 new_ace_list = talloc_zero_array(talloc_tos(),
 210                                                  struct security_ace,
 211                                                  num_aces + 3);
 212         }
 213
 214         if (new_ace_list == NULL) {
 215                 return NT_STATUS_NO_MEMORY;
 216         }
 217
 218         /* Fake a quick smb_filename. */
 219         ZERO_STRUCT(smb_fname);
 220         smb_fname.st = *psbuf;
 221         smb_fname.base_name = discard_const_p(char, name);
 222
 223         dir_mode = unix_mode(conn,
 224                         FILE_ATTRIBUTE_DIRECTORY, &smb_fname, NULL);
 225         file_mode = unix_mode(conn,
 226                         FILE_ATTRIBUTE_ARCHIVE, &smb_fname, NULL);
 227
 228         mode = dir_mode | file_mode;
 229
 230         DEBUG(10, ("add_directory_inheritable_components: directory %s, "
 231                 "mode = 0%o\n",
 232                 name,
 233                 (unsigned int)mode ));
 234
 235         if (num_aces) {
 236                 memcpy(new_ace_list, psd->dacl->aces,
 237                         num_aces * sizeof(struct security_ace));
 238         }
 239         access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
 240                                 mode & 0700, false);
 241
 242         init_sec_ace(&new_ace_list[num_aces],
 243                         &global_sid_Creator_Owner,
 244                         acltype,
 245                         access_mask,
 246                         SEC_ACE_FLAG_CONTAINER_INHERIT|
 247                                 SEC_ACE_FLAG_OBJECT_INHERIT|
 248                                 SEC_ACE_FLAG_INHERIT_ONLY);
 249         access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
 250                                 (mode << 3) & 0700, false);
 251         init_sec_ace(&new_ace_list[num_aces+1],
 252                         &global_sid_Creator_Group,
 253                         acltype,
 254                         access_mask,
 255                         SEC_ACE_FLAG_CONTAINER_INHERIT|
 256                                 SEC_ACE_FLAG_OBJECT_INHERIT|
 257                                 SEC_ACE_FLAG_INHERIT_ONLY);
 258         access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
 259                                 (mode << 6) & 0700, false);
 260         init_sec_ace(&new_ace_list[num_aces+2],
 261                         &global_sid_World,
 262                         acltype,
 263                         access_mask,
 264                         SEC_ACE_FLAG_CONTAINER_INHERIT|
 265                                 SEC_ACE_FLAG_OBJECT_INHERIT|
 266                                 SEC_ACE_FLAG_INHERIT_ONLY);
 267         if (psd->dacl) {
 268                 psd->dacl->aces = new_ace_list;
 269                 psd->dacl->num_aces += 3;
 270         } else {
 271                 psd->dacl = make_sec_acl(psd,
 272                                 NT4_ACL_REVISION,
 273                                 3,
 274                                 new_ace_list);
 275                 if (psd->dacl == NULL) {
 276                         return NT_STATUS_NO_MEMORY;
 277                 }
 278         }
 279         return NT_STATUS_OK;
 280 }
 281
 282 /*******************************************************************
 283  Pull a DATA_BLOB from an xattr given a pathname.
 284  If the hash doesn't match, or doesn't exist - return the underlying
 285  filesystem sd.
 286 *******************************************************************/
 287
 288 static NTSTATUS get_nt_acl_internal(vfs_handle_struct *handle,
 289                                 files_struct *fsp,
 290                                 const char *name,
 291                                 uint32_t security_info,
 292                                 TALLOC_CTX *mem_ctx,
 293                                     struct security_descriptor **ppdesc)
 294 {
 295         DATA_BLOB blob = data_blob_null;
 296         NTSTATUS status;
 297         uint16_t hash_type = XATTR_SD_HASH_TYPE_NONE;
 298         uint8_t hash[XATTR_SD_HASH_SIZE];
 299         uint8_t hash_tmp[XATTR_SD_HASH_SIZE];
 300         struct security_descriptor *psd = NULL;
 301         struct security_descriptor *pdesc_next = NULL;
 302         bool ignore_file_system_acl = lp_parm_bool(SNUM(handle->conn),
 303                                                 ACL_MODULE_NAME,
 304                                                 "ignore system acls",
 305                                                 false);
 306
 307         if (fsp && name == NULL) {
 308                 name = fsp->fsp_name->base_name;
 309         }
 310
 311         DEBUG(10, ("get_nt_acl_internal: name=%s\n", name));
 312
 313         /* Get the full underlying sd for the hash
 314            or to return as backup. */
 315         if (fsp) {
 316                 status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
 317                                                   fsp,
 318                                                   HASH_SECURITY_INFO,
 319                                                   mem_ctx,
 320                                                   &pdesc_next);
 321         } else {
 322                 status = SMB_VFS_NEXT_GET_NT_ACL(handle,
 323                                                  name,
 324                                                  HASH_SECURITY_INFO,
 325                                                  mem_ctx,
 326                                                  &pdesc_next);
 327         }
 328
 329         if (!NT_STATUS_IS_OK(status)) {
 330                 DEBUG(10, ("get_nt_acl_internal: get_next_acl for file %s "
 331                         "returned %s\n",
 332                         name,
 333                         nt_errstr(status)));
 334                 return status;
 335         }
 336
 337         status = get_acl_blob(talloc_tos(), handle, fsp, name, &blob);
 338         if (!NT_STATUS_IS_OK(status)) {
 339                 DEBUG(10, ("get_nt_acl_internal: get_acl_blob returned %s\n",
 340                         nt_errstr(status)));
 341                 psd = pdesc_next;
 342                 goto out;
 343         }
 344
 345         status = parse_acl_blob(&blob, mem_ctx, &psd,
 346                                 &hash_type, &hash[0]);
 347         if (!NT_STATUS_IS_OK(status)) {
 348                 DEBUG(10, ("parse_acl_blob returned %s\n",
 349                                 nt_errstr(status)));
 350                 psd = pdesc_next;
 351                 goto out;
 352         }
 353
 354         /* Ensure the hash type is one we know. */
 355         switch (hash_type) {
 356                 case XATTR_SD_HASH_TYPE_NONE:
 357                         /* No hash, just return blob sd. */
 358                         goto out;
 359                 case XATTR_SD_HASH_TYPE_SHA256:
 360                         break;
 361                 default:
 362                         DEBUG(10, ("get_nt_acl_internal: ACL blob revision "
 363                                 "mismatch (%u) for file %s\n",
 364                                 (unsigned int)hash_type,
 365                                 name));
 366                         TALLOC_FREE(psd);
 367                         psd = pdesc_next;
 368                         goto out;
 369         }
 370
 371         if (ignore_file_system_acl) {
 372                 goto out;
 373         }
 374
 375         status = hash_sd_sha256(pdesc_next, hash_tmp);
 376         if (!NT_STATUS_IS_OK(status)) {
 377                 TALLOC_FREE(psd);
 378                 psd = pdesc_next;
 379                 goto out;
 380         }
 381
 382         if (memcmp(&hash[0], &hash_tmp[0], XATTR_SD_HASH_SIZE) == 0) {
 383                 /* Hash matches, return blob sd. */
 384                 DEBUG(10, ("get_nt_acl_internal: blob hash "
 385                         "matches for file %s\n",
 386                         name ));
 387                 goto out;
 388         }
 389
 390         /* Hash doesn't match, return underlying sd. */
 391         DEBUG(10, ("get_nt_acl_internal: blob hash "
 392                 "does not match for file %s - returning "
 393                 "file system SD mapping.\n",
 394                 name ));
 395
 396         if (DEBUGLEVEL >= 10) {
 397                 DEBUG(10,("get_nt_acl_internal: acl for blob hash for %s is:\n",
 398                         name ));
 399                 NDR_PRINT_DEBUG(security_descriptor, pdesc_next);
 400         }
 401
 402         TALLOC_FREE(psd);
 403         psd = pdesc_next;
 404
 405   out:
 406
 407         if (psd != pdesc_next) {
 408                 /* We're returning the blob, throw
 409                  * away the filesystem SD. */
 410                 TALLOC_FREE(pdesc_next);
 411         } else {
 412                 SMB_STRUCT_STAT sbuf;
 413                 SMB_STRUCT_STAT *psbuf = &sbuf;
 414                 bool is_directory = false;
 415                 /*
 416                  * We're returning the underlying ACL from the
 417                  * filesystem. If it's a directory, and has no
 418                  * inheritable ACE entries we have to fake them.
 419                  */
 420                 if (fsp) {
 421                         status = vfs_stat_fsp(fsp);
 422                         if (!NT_STATUS_IS_OK(status)) {
 423                                 return status;
 424                         }
 425                         psbuf = &fsp->fsp_name->st;
 426                 } else {
 427                         int ret = vfs_stat_smb_fname(handle->conn,
 428                                                 name,
 429                                                 &sbuf);
 430                         if (ret == -1) {
 431                                 return map_nt_error_from_unix(errno);
 432                         }
 433                 }
 434                 is_directory = S_ISDIR(psbuf->st_ex_mode);
 435
 436                 if (ignore_file_system_acl) {
 437                         TALLOC_FREE(pdesc_next);
 438                         status = make_default_filesystem_acl(mem_ctx,
 439                                                 name,
 440                                                 psbuf,
 441                                                 &psd);
 442                         if (!NT_STATUS_IS_OK(status)) {
 443                                 return status;
 444                         }
 445                 } else {
 446                         if (is_directory &&
 447                                 !sd_has_inheritable_components(psd,
 448                                                         true)) {
 449                                 status = add_directory_inheritable_components(
 450                                                         handle,
 451                                                         name,
 452                                                         psbuf,
 453                                                         psd);
 454                                 if (!NT_STATUS_IS_OK(status)) {
 455                                         return status;
 456                                 }
 457                         }
 458                         /* The underlying POSIX module always sets
 459                            the ~SEC_DESC_DACL_PROTECTED bit, as ACLs
 460                            can't be inherited in this way under POSIX.
 461                            Remove it for Windows-style ACLs. */
 462                         psd->type &= ~SEC_DESC_DACL_PROTECTED;
 463                 }
 464         }
 465
 466         if (!(security_info & SECINFO_OWNER)) {
 467                 psd->owner_sid = NULL;
 468         }
 469         if (!(security_info & SECINFO_GROUP)) {
 470                 psd->group_sid = NULL;
 471         }
 472         if (!(security_info & SECINFO_DACL)) {
 473                 psd->type &= ~SEC_DESC_DACL_PRESENT;
 474                 psd->dacl = NULL;
 475         }
 476         if (!(security_info & SECINFO_SACL)) {
 477                 psd->type &= ~SEC_DESC_SACL_PRESENT;
 478                 psd->sacl = NULL;
 479         }
 480
 481         TALLOC_FREE(blob.data);
 482         *ppdesc = psd;
 483
 484         if (DEBUGLEVEL >= 10) {
 485                 DEBUG(10,("get_nt_acl_internal: returning acl for %s is:\n",
 486                         name ));
 487                 NDR_PRINT_DEBUG(security_descriptor, psd);
 488         }
 489
 490         return NT_STATUS_OK;
 491 }
 492
 493 /*********************************************************************
 494  Fetch a security descriptor given an fsp.
 495 *********************************************************************/
 496
 497 static NTSTATUS fget_nt_acl_common(vfs_handle_struct *handle,
 498                                    files_struct *fsp,
 499                                    uint32_t security_info,
 500                                    TALLOC_CTX *mem_ctx,
 501                                    struct security_descriptor **ppdesc)
 502 {
 503         return get_nt_acl_internal(handle, fsp,
 504                                    NULL, security_info, mem_ctx, ppdesc);
 505 }
 506
 507 /*********************************************************************
 508  Fetch a security descriptor given a pathname.
 509 *********************************************************************/
 510
 511 static NTSTATUS get_nt_acl_common(vfs_handle_struct *handle,
 512                                   const char *name,
 513                                   uint32_t security_info,
 514                                   TALLOC_CTX *mem_ctx,
 515                                   struct security_descriptor **ppdesc)
 516 {
 517         return get_nt_acl_internal(handle, NULL,
 518                                    name, security_info, mem_ctx, ppdesc);
 519 }
 520
 521 /*********************************************************************
 522  Store a security descriptor given an fsp.
 523 *********************************************************************/
 524
 525 static NTSTATUS fset_nt_acl_common(vfs_handle_struct *handle, files_struct *fsp,
 526         uint32_t security_info_sent, const struct security_descriptor *orig_psd)
 527 {
 528         NTSTATUS status;
 529         DATA_BLOB blob;
 530         struct security_descriptor *pdesc_next = NULL;
 531         struct security_descriptor *psd = NULL;
 532         uint8_t hash[XATTR_SD_HASH_SIZE];
 533         bool chown_needed = false;
 534         TALLOC_CTX *frame = talloc_stackframe();
 535
 536         if (DEBUGLEVEL >= 10) {
 537                 DEBUG(10,("fset_nt_acl_xattr: incoming sd for file %s\n",
 538                           fsp_str_dbg(fsp)));
 539                 NDR_PRINT_DEBUG(security_descriptor,
 540                         discard_const_p(struct security_descriptor, orig_psd));
 541         }
 542
 543         status = get_nt_acl_internal(handle, fsp,
 544                         NULL,
 545                         SECINFO_OWNER|SECINFO_GROUP|SECINFO_DACL|SECINFO_SACL,
 546                                      frame,
 547                         &psd);
 548
 549         if (!NT_STATUS_IS_OK(status)) {
 550                 TALLOC_FREE(frame);
 551                 return status;
 552         }
 553
 554         psd->revision = orig_psd->revision;
 555         /* All our SD's are self relative. */
 556         psd->type = orig_psd->type | SEC_DESC_SELF_RELATIVE;
 557
 558         if ((security_info_sent & SECINFO_OWNER) && (orig_psd->owner_sid != NULL)) {
 559                 if (!dom_sid_equal(orig_psd->owner_sid, psd->owner_sid)) {
 560                         /* We're changing the owner. */
 561                         chown_needed = true;
 562                 }
 563                 psd->owner_sid = orig_psd->owner_sid;
 564         }
 565         if ((security_info_sent & SECINFO_GROUP) && (orig_psd->group_sid != NULL)) {
 566                 if (!dom_sid_equal(orig_psd->group_sid, psd->group_sid)) {
 567                         /* We're changing the group. */
 568                         chown_needed = true;
 569                 }
 570                 psd->group_sid = orig_psd->group_sid;
 571         }
 572         if (security_info_sent & SECINFO_DACL) {
 573                 psd->dacl = orig_psd->dacl;
 574                 psd->type |= SEC_DESC_DACL_PRESENT;
 575         }
 576         if (security_info_sent & SECINFO_SACL) {
 577                 psd->sacl = orig_psd->sacl;
 578                 psd->type |= SEC_DESC_SACL_PRESENT;
 579         }
 580
 581         status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
 582         if (!NT_STATUS_IS_OK(status)) {
 583                 if (!NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED)) {
 584                         TALLOC_FREE(frame);
 585                         return status;
 586                 }
 587                 /* We got access denied here. If we're already root,
 588                    or we didn't need to do a chown, or the fsp isn't
 589                    open with WRITE_OWNER access, just return. */
 590                 if (get_current_uid(handle->conn) == 0 ||
 591                                 chown_needed == false ||
 592                                 !(fsp->access_mask & SEC_STD_WRITE_OWNER)) {
 593                         TALLOC_FREE(frame);
 594                         return NT_STATUS_ACCESS_DENIED;
 595                 }
 596
 597                 DEBUG(10,("fset_nt_acl_common: overriding chown on file %s "
 598                         "for sid %s\n",
 599                         fsp_str_dbg(fsp),
 600                         sid_string_tos(psd->owner_sid)
 601                         ));
 602
 603                 /* Ok, we failed to chown and we have
 604                    SEC_STD_WRITE_OWNER access - override. */
 605                 become_root();
 606                 status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp,
 607                                 security_info_sent, psd);
 608                 unbecome_root();
 609                 if (!NT_STATUS_IS_OK(status)) {
 610                         TALLOC_FREE(frame);
 611                         return status;
 612                 }
 613         }
 614
 615         /* Get the full underlying sd, then hash. */
 616         status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
 617                                           fsp,
 618                                           HASH_SECURITY_INFO,
 619                                           frame,
 620                                           &pdesc_next);
 621
 622         if (!NT_STATUS_IS_OK(status)) {
 623                 TALLOC_FREE(frame);
 624                 return status;
 625         }
 626
 627         status = hash_sd_sha256(pdesc_next, hash);
 628         if (!NT_STATUS_IS_OK(status)) {
 629                 TALLOC_FREE(frame);
 630                 return status;
 631         }
 632
 633         if (DEBUGLEVEL >= 10) {
 634                 DEBUG(10,("fset_nt_acl_xattr: storing xattr sd for file %s\n",
 635                           fsp_str_dbg(fsp)));
 636                 NDR_PRINT_DEBUG(security_descriptor,
 637                         discard_const_p(struct security_descriptor, psd));
 638
 639                 DEBUG(10,("fset_nt_acl_xattr: storing has in xattr sd based on \n"));
 640                 NDR_PRINT_DEBUG(security_descriptor,
 641                         discard_const_p(struct security_descriptor, pdesc_next));
 642         }
 643         status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
 644         if (!NT_STATUS_IS_OK(status)) {
 645                 DEBUG(10, ("fset_nt_acl_xattr: create_acl_blob failed\n"));
 646                 TALLOC_FREE(frame);
 647                 return status;
 648         }
 649
 650         status = store_acl_blob_fsp(handle, fsp, &blob);
 651
 652         TALLOC_FREE(frame);
 653         return status;
 654 }
 655
 656 static int acl_common_remove_object(vfs_handle_struct *handle,
 657                                         const char *path,
 658                                         bool is_directory)
 659 {
 660         connection_struct *conn = handle->conn;
 661         struct file_id id;
 662         files_struct *fsp = NULL;
 663         int ret = 0;
 664         char *parent_dir = NULL;
 665         const char *final_component = NULL;
 666         struct smb_filename local_fname;
 667         int saved_errno = 0;
 668         char *saved_dir = NULL;
 669
 670         saved_dir = vfs_GetWd(talloc_tos(),conn);
 671         if (!saved_dir) {
 672                 saved_errno = errno;
 673                 goto out;
 674         }
 675
 676         if (!parent_dirname(talloc_tos(), path,
 677                         &parent_dir, &final_component)) {
 678                 saved_errno = ENOMEM;
 679                 goto out;
 680         }
 681
 682         DEBUG(10,("acl_common_remove_object: removing %s %s/%s\n",
 683                 is_directory ? "directory" : "file",
 684                 parent_dir, final_component ));
 685
 686         /* cd into the parent dir to pin it. */
 687         ret = vfs_ChDir(conn, parent_dir);
 688         if (ret == -1) {
 689                 saved_errno = errno;
 690                 goto out;
 691         }
 692
 693         ZERO_STRUCT(local_fname);
 694         local_fname.base_name = discard_const_p(char, final_component);
 695
 696         /* Must use lstat here. */
 697         ret = SMB_VFS_LSTAT(conn, &local_fname);
 698         if (ret == -1) {
 699                 saved_errno = errno;
 700                 goto out;
 701         }
 702
 703         /* Ensure we have this file open with DELETE access. */
 704         id = vfs_file_id_from_sbuf(conn, &local_fname.st);
 705         for (fsp = file_find_di_first(conn->sconn, id); fsp;
 706                      fsp = file_find_di_next(fsp)) {
 707                 if (fsp->access_mask & DELETE_ACCESS &&
 708                                 fsp->delete_on_close) {
 709                         /* We did open this for delete,
 710                          * allow the delete as root.
 711                          */
 712                         break;
 713                 }
 714         }
 715
 716         if (!fsp) {
 717                 DEBUG(10,("acl_common_remove_object: %s %s/%s "
 718                         "not an open file\n",
 719                         is_directory ? "directory" : "file",
 720                         parent_dir, final_component ));
 721                 saved_errno = EACCES;
 722                 goto out;
 723         }
 724
 725         become_root();
 726         if (is_directory) {
 727                 ret = SMB_VFS_NEXT_RMDIR(handle, final_component);
 728         } else {
 729                 ret = SMB_VFS_NEXT_UNLINK(handle, &local_fname);
 730         }
 731         unbecome_root();
 732
 733         if (ret == -1) {
 734                 saved_errno = errno;
 735         }
 736
 737   out:
 738
 739         TALLOC_FREE(parent_dir);
 740
 741         if (saved_dir) {
 742                 vfs_ChDir(conn, saved_dir);
 743         }
 744         if (saved_errno) {
 745                 errno = saved_errno;
 746         }
 747         return ret;
 748 }
 749
 750 static int rmdir_acl_common(struct vfs_handle_struct *handle,
 751                                 const char *path)
 752 {
 753         int ret;
 754
 755         /* Try the normal rmdir first. */
 756         ret = SMB_VFS_NEXT_RMDIR(handle, path);
 757         if (ret == 0) {
 758                 return 0;
 759         }
 760         if (errno == EACCES || errno == EPERM) {
 761                 /* Failed due to access denied,
 762                    see if we need to root override. */
 763                 return acl_common_remove_object(handle,
 764                                                 path,
 765                                                 true);
 766         }
 767
 768         DEBUG(10,("rmdir_acl_common: unlink of %s failed %s\n",
 769                 path,
 770                 strerror(errno) ));
 771         return -1;
 772 }
 773
 774 static int unlink_acl_common(struct vfs_handle_struct *handle,
 775                         const struct smb_filename *smb_fname)
 776 {
 777         int ret;
 778
 779         /* Try the normal unlink first. */
 780         ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname);
 781         if (ret == 0) {
 782                 return 0;
 783         }
 784         if (errno == EACCES || errno == EPERM) {
 785                 /* Failed due to access denied,
 786                    see if we need to root override. */
 787
 788                 /* Don't do anything fancy for streams. */
 789                 if (smb_fname->stream_name) {
 790                         return -1;
 791                 }
 792                 return acl_common_remove_object(handle,
 793                                         smb_fname->base_name,
 794                                         false);
 795         }
 796
 797         DEBUG(10,("unlink_acl_common: unlink of %s failed %s\n",
 798                 smb_fname->base_name,
 799                 strerror(errno) ));
 800         return -1;
 801 }
 802
 803 static int chmod_acl_module_common(struct vfs_handle_struct *handle,
 804                         const char *path, mode_t mode)
 805 {
 806         if (lp_posix_pathnames()) {
 807                 /* Only allow this on POSIX pathnames. */
 808                 return SMB_VFS_NEXT_CHMOD(handle, path, mode);
 809         }
 810         return 0;
 811 }
 812
 813 static int fchmod_acl_module_common(struct vfs_handle_struct *handle,
 814                         struct files_struct *fsp, mode_t mode)
 815 {
 816         if (fsp->posix_open) {
 817                 /* Only allow this on POSIX opens. */
 818                 return SMB_VFS_NEXT_FCHMOD(handle, fsp, mode);
 819         }
 820         return 0;
 821 }
 822
 823 static int chmod_acl_acl_module_common(struct vfs_handle_struct *handle,
 824                         const char *name, mode_t mode)
 825 {
 826         if (lp_posix_pathnames()) {
 827                 /* Only allow this on POSIX pathnames. */
 828                 return SMB_VFS_NEXT_CHMOD_ACL(handle, name, mode);
 829         }
 830         return 0;
 831 }
 832
 833 static int fchmod_acl_acl_module_common(struct vfs_handle_struct *handle,
 834                         struct files_struct *fsp, mode_t mode)
 835 {
 836         if (fsp->posix_open) {
 837                 /* Only allow this on POSIX opens. */
 838                 return SMB_VFS_NEXT_FCHMOD_ACL(handle, fsp, mode);
 839         }
 840         return 0;
 841 }