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  * Copyright (C) Ralph Böhme, 2016
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 3 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  21  */
  22
  23 #include "includes.h"
  24 #include "vfs_acl_common.h"
  25 #include "smbd/smbd.h"
  26 #include "system/filesys.h"
  27 #include "librpc/gen_ndr/ndr_xattr.h"
  28 #include "../libcli/security/security.h"
  29 #include "../librpc/gen_ndr/ndr_security.h"
  30 #include "../lib/util/bitmap.h"
  31 #include "passdb/lookup_sid.h"
  32
  33 #include <gnutls/gnutls.h>
  34 #include <gnutls/crypto.h>
  35
  36 static NTSTATUS create_acl_blob(const struct security_descriptor *psd,
  37                         DATA_BLOB *pblob,
  38                         uint16_t hash_type,
  39                         uint8_t hash[XATTR_SD_HASH_SIZE]);
  40
  41 #define HASH_SECURITY_INFO (SECINFO_OWNER | \
  42                                 SECINFO_GROUP | \
  43                                 SECINFO_DACL | \
  44                                 SECINFO_SACL)
  45
  46 bool init_acl_common_config(vfs_handle_struct *handle,
  47                             const char *module_name)
  48 {
  49         struct acl_common_config *config = NULL;
  50         const struct enum_list *default_acl_style_list = NULL;
  51
  52         default_acl_style_list = get_default_acl_style_list();
  53
  54         config = talloc_zero(handle->conn, struct acl_common_config);
  55         if (config == NULL) {
  56                 DBG_ERR("talloc_zero() failed\n");
  57                 errno = ENOMEM;
  58                 return false;
  59         }
  60
  61         config->ignore_system_acls = lp_parm_bool(SNUM(handle->conn),
  62                                                   module_name,
  63                                                   "ignore system acls",
  64                                                   false);
  65         config->default_acl_style = lp_parm_enum(SNUM(handle->conn),
  66                                                  module_name,
  67                                                  "default acl style",
  68                                                  default_acl_style_list,
  69                                                  DEFAULT_ACL_POSIX);
  70
  71         SMB_VFS_HANDLE_SET_DATA(handle, config, NULL,
  72                                 struct acl_common_config,
  73                                 return false);
  74
  75         return true;
  76 }
  77
  78
  79 /*******************************************************************
  80  Hash a security descriptor.
  81 *******************************************************************/
  82
  83 static NTSTATUS hash_blob_sha256(DATA_BLOB blob,
  84                                  uint8_t *hash)
  85 {
  86         int rc;
  87
  88         ZERO_ARRAY_LEN(hash, XATTR_SD_HASH_SIZE);
  89
  90         rc = gnutls_hash_fast(GNUTLS_DIG_SHA256,
  91                               blob.data,
  92                               blob.length,
  93                               hash);
  94         if (rc < 0) {
  95                 return NT_STATUS_INTERNAL_ERROR;
  96         }
  97
  98         return NT_STATUS_OK;
  99 }
 100
 101 /*******************************************************************
 102  Hash a security descriptor.
 103 *******************************************************************/
 104
 105 static NTSTATUS hash_sd_sha256(struct security_descriptor *psd,
 106                         uint8_t *hash)
 107 {
 108         DATA_BLOB blob;
 109         NTSTATUS status;
 110
 111         memset(hash, '\0', XATTR_SD_HASH_SIZE);
 112         status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
 113         if (!NT_STATUS_IS_OK(status)) {
 114                 return status;
 115         }
 116         return hash_blob_sha256(blob, hash);
 117 }
 118
 119 /*******************************************************************
 120  Parse out a struct security_descriptor from a DATA_BLOB.
 121 *******************************************************************/
 122
 123 static NTSTATUS parse_acl_blob(const DATA_BLOB *pblob,
 124                                TALLOC_CTX *mem_ctx,
 125                                struct security_descriptor **ppdesc,
 126                                uint16_t *p_hash_type,
 127                                uint16_t *p_version,
 128                                uint8_t hash[XATTR_SD_HASH_SIZE],
 129                                uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE])
 130 {
 131         struct xattr_NTACL xacl;
 132         enum ndr_err_code ndr_err;
 133         size_t sd_size;
 134         TALLOC_CTX *frame = talloc_stackframe();
 135
 136         ndr_err = ndr_pull_struct_blob(pblob, frame, &xacl,
 137                         (ndr_pull_flags_fn_t)ndr_pull_xattr_NTACL);
 138
 139         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 140                 DBG_INFO("ndr_pull_xattr_NTACL failed: %s\n",
 141                          ndr_errstr(ndr_err));
 142                 TALLOC_FREE(frame);
 143                 return ndr_map_error2ntstatus(ndr_err);
 144         }
 145
 146         *p_version = xacl.version;
 147
 148         switch (xacl.version) {
 149                 case 1:
 150                         *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
 151                                         xacl.info.sd->type | SEC_DESC_SELF_RELATIVE,
 152                                         xacl.info.sd->owner_sid,
 153                                         xacl.info.sd->group_sid,
 154                                         xacl.info.sd->sacl,
 155                                         xacl.info.sd->dacl,
 156                                         &sd_size);
 157                         /* No hash - null out. */
 158                         *p_hash_type = XATTR_SD_HASH_TYPE_NONE;
 159                         memset(hash, '\0', XATTR_SD_HASH_SIZE);
 160                         break;
 161                 case 2:
 162                         *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
 163                                         xacl.info.sd_hs2->sd->type | SEC_DESC_SELF_RELATIVE,
 164                                         xacl.info.sd_hs2->sd->owner_sid,
 165                                         xacl.info.sd_hs2->sd->group_sid,
 166                                         xacl.info.sd_hs2->sd->sacl,
 167                                         xacl.info.sd_hs2->sd->dacl,
 168                                         &sd_size);
 169                         /* No hash - null out. */
 170                         *p_hash_type = XATTR_SD_HASH_TYPE_NONE;
 171                         memset(hash, '\0', XATTR_SD_HASH_SIZE);
 172                         break;
 173                 case 3:
 174                         *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
 175                                         xacl.info.sd_hs3->sd->type | SEC_DESC_SELF_RELATIVE,
 176                                         xacl.info.sd_hs3->sd->owner_sid,
 177                                         xacl.info.sd_hs3->sd->group_sid,
 178                                         xacl.info.sd_hs3->sd->sacl,
 179                                         xacl.info.sd_hs3->sd->dacl,
 180                                         &sd_size);
 181                         *p_hash_type = xacl.info.sd_hs3->hash_type;
 182                         /* Current version 3 (if no sys acl hash available). */
 183                         memcpy(hash, xacl.info.sd_hs3->hash, XATTR_SD_HASH_SIZE);
 184                         break;
 185                 case 4:
 186                         *ppdesc = make_sec_desc(mem_ctx, SD_REVISION,
 187                                         xacl.info.sd_hs4->sd->type | SEC_DESC_SELF_RELATIVE,
 188                                         xacl.info.sd_hs4->sd->owner_sid,
 189                                         xacl.info.sd_hs4->sd->group_sid,
 190                                         xacl.info.sd_hs4->sd->sacl,
 191                                         xacl.info.sd_hs4->sd->dacl,
 192                                         &sd_size);
 193                         *p_hash_type = xacl.info.sd_hs4->hash_type;
 194                         /* Current version 4. */
 195                         memcpy(hash, xacl.info.sd_hs4->hash, XATTR_SD_HASH_SIZE);
 196                         memcpy(sys_acl_hash, xacl.info.sd_hs4->sys_acl_hash, XATTR_SD_HASH_SIZE);
 197                         break;
 198                 default:
 199                         TALLOC_FREE(frame);
 200                         return NT_STATUS_REVISION_MISMATCH;
 201         }
 202
 203         TALLOC_FREE(frame);
 204
 205         return (*ppdesc != NULL) ? NT_STATUS_OK : NT_STATUS_NO_MEMORY;
 206 }
 207
 208 /*******************************************************************
 209  Create a DATA_BLOB from a hash of the security descriptor storead at
 210  the system layer and the NT ACL we wish to preserve
 211 *******************************************************************/
 212
 213 static NTSTATUS create_acl_blob(const struct security_descriptor *psd,
 214                         DATA_BLOB *pblob,
 215                         uint16_t hash_type,
 216                         uint8_t hash[XATTR_SD_HASH_SIZE])
 217 {
 218         struct xattr_NTACL xacl;
 219         struct security_descriptor_hash_v3 sd_hs3;
 220         enum ndr_err_code ndr_err;
 221         TALLOC_CTX *ctx = talloc_tos();
 222
 223         ZERO_STRUCT(xacl);
 224         ZERO_STRUCT(sd_hs3);
 225
 226         xacl.version = 3;
 227         xacl.info.sd_hs3 = &sd_hs3;
 228         xacl.info.sd_hs3->sd = discard_const_p(struct security_descriptor, psd);
 229         xacl.info.sd_hs3->hash_type = hash_type;
 230         memcpy(&xacl.info.sd_hs3->hash[0], hash, XATTR_SD_HASH_SIZE);
 231
 232         ndr_err = ndr_push_struct_blob(
 233                         pblob, ctx, &xacl,
 234                         (ndr_push_flags_fn_t)ndr_push_xattr_NTACL);
 235
 236         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 237                 DBG_INFO("ndr_push_xattr_NTACL failed: %s\n",
 238                          ndr_errstr(ndr_err));
 239                 return ndr_map_error2ntstatus(ndr_err);
 240         }
 241
 242         return NT_STATUS_OK;
 243 }
 244
 245 /*******************************************************************
 246  Create a DATA_BLOB from a hash of the security descriptors
 247  (system and NT) stored at the system layer and the NT ACL we wish
 248  to preserve.
 249 *******************************************************************/
 250
 251 static NTSTATUS create_sys_acl_blob(const struct security_descriptor *psd,
 252                                     DATA_BLOB *pblob,
 253                                     uint16_t hash_type,
 254                                     uint8_t hash[XATTR_SD_HASH_SIZE],
 255                                     const char *description,
 256                                     uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE])
 257 {
 258         struct xattr_NTACL xacl;
 259         struct security_descriptor_hash_v4 sd_hs4;
 260         enum ndr_err_code ndr_err;
 261         TALLOC_CTX *ctx = talloc_tos();
 262         NTTIME nttime_now;
 263         struct timeval now = timeval_current();
 264         nttime_now = timeval_to_nttime(&now);
 265
 266         ZERO_STRUCT(xacl);
 267         ZERO_STRUCT(sd_hs4);
 268
 269         xacl.version = 4;
 270         xacl.info.sd_hs4 = &sd_hs4;
 271         xacl.info.sd_hs4->sd = discard_const_p(struct security_descriptor, psd);
 272         xacl.info.sd_hs4->hash_type = hash_type;
 273         memcpy(&xacl.info.sd_hs4->hash[0], hash, XATTR_SD_HASH_SIZE);
 274         xacl.info.sd_hs4->description = description;
 275         xacl.info.sd_hs4->time = nttime_now;
 276         memcpy(&xacl.info.sd_hs4->sys_acl_hash[0], sys_acl_hash, XATTR_SD_HASH_SIZE);
 277
 278         ndr_err = ndr_push_struct_blob(
 279                         pblob, ctx, &xacl,
 280                         (ndr_push_flags_fn_t)ndr_push_xattr_NTACL);
 281
 282         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 283                 DBG_INFO("ndr_push_xattr_NTACL failed: %s\n",
 284                          ndr_errstr(ndr_err));
 285                 return ndr_map_error2ntstatus(ndr_err);
 286         }
 287
 288         return NT_STATUS_OK;
 289 }
 290
 291 /*******************************************************************
 292  Add in 3 inheritable components for a non-inheritable directory ACL.
 293  CREATOR_OWNER/CREATOR_GROUP/WORLD.
 294 *******************************************************************/
 295
 296 static NTSTATUS add_directory_inheritable_components(vfs_handle_struct *handle,
 297                                 const char *name,
 298                                 SMB_STRUCT_STAT *psbuf,
 299                                 struct security_descriptor *psd)
 300 {
 301         struct connection_struct *conn = handle->conn;
 302         int num_aces = (psd->dacl ? psd->dacl->num_aces : 0);
 303         struct smb_filename smb_fname;
 304         enum security_ace_type acltype;
 305         uint32_t access_mask;
 306         mode_t dir_mode;
 307         mode_t file_mode;
 308         mode_t mode;
 309         struct security_ace *new_ace_list;
 310
 311         if (psd->dacl) {
 312                 new_ace_list = talloc_zero_array(psd->dacl,
 313                                                  struct security_ace,
 314                                                  num_aces + 3);
 315         } else {
 316                 /*
 317                  * make_sec_acl() at the bottom of this function
 318                  * dupliates new_ace_list
 319                  */
 320                 new_ace_list = talloc_zero_array(talloc_tos(),
 321                                                  struct security_ace,
 322                                                  num_aces + 3);
 323         }
 324
 325         if (new_ace_list == NULL) {
 326                 return NT_STATUS_NO_MEMORY;
 327         }
 328
 329         /* Fake a quick smb_filename. */
 330         ZERO_STRUCT(smb_fname);
 331         smb_fname.st = *psbuf;
 332         smb_fname.base_name = discard_const_p(char, name);
 333
 334         dir_mode = unix_mode(conn,
 335                         FILE_ATTRIBUTE_DIRECTORY, &smb_fname, NULL);
 336         file_mode = unix_mode(conn,
 337                         FILE_ATTRIBUTE_ARCHIVE, &smb_fname, NULL);
 338
 339         mode = dir_mode | file_mode;
 340
 341         DBG_DEBUG("directory %s, mode = 0%o\n", name, (unsigned int)mode);
 342
 343         if (num_aces) {
 344                 memcpy(new_ace_list, psd->dacl->aces,
 345                         num_aces * sizeof(struct security_ace));
 346         }
 347         access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
 348                                 mode & 0700, false);
 349
 350         init_sec_ace(&new_ace_list[num_aces],
 351                         &global_sid_Creator_Owner,
 352                         acltype,
 353                         access_mask,
 354                         SEC_ACE_FLAG_CONTAINER_INHERIT|
 355                                 SEC_ACE_FLAG_OBJECT_INHERIT|
 356                                 SEC_ACE_FLAG_INHERIT_ONLY);
 357         access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
 358                                 (mode << 3) & 0700, false);
 359         init_sec_ace(&new_ace_list[num_aces+1],
 360                         &global_sid_Creator_Group,
 361                         acltype,
 362                         access_mask,
 363                         SEC_ACE_FLAG_CONTAINER_INHERIT|
 364                                 SEC_ACE_FLAG_OBJECT_INHERIT|
 365                                 SEC_ACE_FLAG_INHERIT_ONLY);
 366         access_mask = map_canon_ace_perms(SNUM(conn), &acltype,
 367                                 (mode << 6) & 0700, false);
 368         init_sec_ace(&new_ace_list[num_aces+2],
 369                         &global_sid_World,
 370                         acltype,
 371                         access_mask,
 372                         SEC_ACE_FLAG_CONTAINER_INHERIT|
 373                                 SEC_ACE_FLAG_OBJECT_INHERIT|
 374                                 SEC_ACE_FLAG_INHERIT_ONLY);
 375         if (psd->dacl) {
 376                 psd->dacl->aces = new_ace_list;
 377                 psd->dacl->num_aces += 3;
 378                 psd->dacl->size += new_ace_list[num_aces].size +
 379                         new_ace_list[num_aces+1].size +
 380                         new_ace_list[num_aces+2].size;
 381         } else {
 382                 psd->dacl = make_sec_acl(psd,
 383                                 NT4_ACL_REVISION,
 384                                 3,
 385                                 new_ace_list);
 386                 if (psd->dacl == NULL) {
 387                         return NT_STATUS_NO_MEMORY;
 388                 }
 389         }
 390         return NT_STATUS_OK;
 391 }
 392
 393 /**
 394  * Validate an ACL blob
 395  *
 396  * This validates an ACL blob against the underlying filesystem ACL. If this
 397  * function returns NT_STATUS_OK ppsd can be
 398  *
 399  * 1. the ACL from the blob (psd_from_fs=false), or
 400  * 2. the ACL from the fs (psd_from_fs=true), or
 401  * 3. NULL (!)
 402  *
 403  * If the return value is anything else then NT_STATUS_OK, ppsd is set to NULL
 404  * and psd_from_fs set to false.
 405  *
 406  * Returning the underlying filesystem ACL in case no. 2 is really just an
 407  * optimisation, because some validations have to fetch the filesytem ACL as
 408  * part of the validation, so we already have it available and callers might
 409  * need it as well.
 410  **/
 411 static NTSTATUS validate_nt_acl_blob(TALLOC_CTX *mem_ctx,
 412                                      vfs_handle_struct *handle,
 413                                      files_struct *fsp,
 414                                      const struct smb_filename *smb_fname,
 415                                      const DATA_BLOB *blob,
 416                                      struct security_descriptor **ppsd,
 417                                      bool *psd_is_from_fs)
 418 {
 419         NTSTATUS status;
 420         uint16_t hash_type = XATTR_SD_HASH_TYPE_NONE;
 421         uint16_t xattr_version = 0;
 422         uint8_t hash[XATTR_SD_HASH_SIZE];
 423         uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE];
 424         uint8_t hash_tmp[XATTR_SD_HASH_SIZE];
 425         uint8_t sys_acl_hash_tmp[XATTR_SD_HASH_SIZE];
 426         struct security_descriptor *psd = NULL;
 427         struct security_descriptor *psd_blob = NULL;
 428         struct security_descriptor *psd_fs = NULL;
 429         char *sys_acl_blob_description = NULL;
 430         DATA_BLOB sys_acl_blob = { 0 };
 431         struct acl_common_config *config = NULL;
 432
 433         *ppsd = NULL;
 434         *psd_is_from_fs = false;
 435
 436         SMB_VFS_HANDLE_GET_DATA(handle, config,
 437                                 struct acl_common_config,
 438                                 return NT_STATUS_UNSUCCESSFUL);
 439
 440         status = parse_acl_blob(blob,
 441                                 mem_ctx,
 442                                 &psd_blob,
 443                                 &hash_type,
 444                                 &xattr_version,
 445                                 &hash[0],
 446                                 &sys_acl_hash[0]);
 447         if (!NT_STATUS_IS_OK(status)) {
 448                 DBG_DEBUG("parse_acl_blob returned %s\n", nt_errstr(status));
 449                 goto fail;
 450         }
 451
 452         /* determine which type of xattr we got */
 453         switch (xattr_version) {
 454         case 1:
 455         case 2:
 456                 /* These xattr types are unilatteral, they do not
 457                  * require confirmation of the hash.  In particular,
 458                  * the NTVFS file server uses version 1, but
 459                  * 'samba-tool ntacl' can set these as well */
 460                 *ppsd = psd_blob;
 461                 return NT_STATUS_OK;
 462         case 3:
 463         case 4:
 464                 if (config->ignore_system_acls) {
 465                         *ppsd = psd_blob;
 466                         return NT_STATUS_OK;
 467                 }
 468
 469                 break;
 470         default:
 471                 DBG_DEBUG("ACL blob revision mismatch (%u) for file %s\n",
 472                           (unsigned int)hash_type, smb_fname->base_name);
 473                 TALLOC_FREE(psd_blob);
 474                 return NT_STATUS_OK;
 475         }
 476
 477         /* determine which type of xattr we got */
 478         if (hash_type != XATTR_SD_HASH_TYPE_SHA256) {
 479                 DBG_DEBUG("ACL blob hash type (%u) unexpected for file %s\n",
 480                           (unsigned int)hash_type, smb_fname->base_name);
 481                 TALLOC_FREE(psd_blob);
 482                 return NT_STATUS_OK;
 483         }
 484
 485         /* determine which type of xattr we got */
 486         switch (xattr_version) {
 487         case 4:
 488         {
 489                 int ret;
 490                 if (fsp) {
 491                         /* Get the full underlying sd, then hash. */
 492                         ret = SMB_VFS_NEXT_SYS_ACL_BLOB_GET_FD(handle,
 493                                                                fsp,
 494                                                                mem_ctx,
 495                                                                &sys_acl_blob_description,
 496                                                                &sys_acl_blob);
 497                 } else {
 498                         /* Get the full underlying sd, then hash. */
 499                         ret = SMB_VFS_NEXT_SYS_ACL_BLOB_GET_FILE(handle,
 500                                                  smb_fname,
 501                                                  mem_ctx,
 502                                                  &sys_acl_blob_description,
 503                                                  &sys_acl_blob);
 504                 }
 505
 506                 /* If we fail to get the ACL blob (for some reason) then this
 507                  * is not fatal, we just work based on the NT ACL only */
 508                 if (ret == 0) {
 509                         status = hash_blob_sha256(sys_acl_blob, sys_acl_hash_tmp);
 510                         if (!NT_STATUS_IS_OK(status)) {
 511                                 goto fail;
 512                         }
 513
 514                         TALLOC_FREE(sys_acl_blob_description);
 515                         TALLOC_FREE(sys_acl_blob.data);
 516
 517                         if (memcmp(&sys_acl_hash[0], &sys_acl_hash_tmp[0],
 518                                    XATTR_SD_HASH_SIZE) == 0) {
 519                                 /* Hash matches, return blob sd. */
 520                                 DBG_DEBUG("blob hash matches for file %s\n",
 521                                           smb_fname->base_name);
 522                                 *ppsd = psd_blob;
 523                                 return NT_STATUS_OK;
 524                         }
 525                 }
 526
 527                 /* Otherwise, fall though and see if the NT ACL hash matches */
 528                 FALL_THROUGH;
 529         }
 530         case 3:
 531                 /* Get the full underlying sd for the hash
 532                    or to return as backup. */
 533                 if (fsp) {
 534                         status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
 535                                                           fsp,
 536                                                           HASH_SECURITY_INFO,
 537                                                           mem_ctx,
 538                                                           &psd_fs);
 539                 } else {
 540                         status = SMB_VFS_NEXT_GET_NT_ACL(handle,
 541                                                          smb_fname,
 542                                                          HASH_SECURITY_INFO,
 543                                                          mem_ctx,
 544                                                          &psd_fs);
 545                 }
 546
 547                 if (!NT_STATUS_IS_OK(status)) {
 548                         DBG_DEBUG("get_next_acl for file %s returned %s\n",
 549                                   smb_fname->base_name, nt_errstr(status));
 550                         goto fail;
 551                 }
 552
 553                 status = hash_sd_sha256(psd_fs, hash_tmp);
 554                 if (!NT_STATUS_IS_OK(status)) {
 555                         TALLOC_FREE(psd_blob);
 556                         *ppsd = psd_fs;
 557                         *psd_is_from_fs = true;
 558                         return NT_STATUS_OK;
 559                 }
 560
 561                 if (memcmp(&hash[0], &hash_tmp[0], XATTR_SD_HASH_SIZE) == 0) {
 562                         /* Hash matches, return blob sd. */
 563                         DBG_DEBUG("blob hash matches for file %s\n",
 564                                   smb_fname->base_name);
 565                         *ppsd = psd_blob;
 566                         return NT_STATUS_OK;
 567                 }
 568
 569                 /* Hash doesn't match, return underlying sd. */
 570                 DBG_DEBUG("blob hash does not match for file %s - returning "
 571                           "file system SD mapping.\n",
 572                           smb_fname->base_name);
 573
 574                 if (DEBUGLEVEL >= 10) {
 575                         DBG_DEBUG("acl for blob hash for %s is:\n",
 576                                   smb_fname->base_name);
 577                         NDR_PRINT_DEBUG(security_descriptor, psd_fs);
 578                 }
 579
 580                 TALLOC_FREE(psd_blob);
 581                 *ppsd = psd_fs;
 582                 *psd_is_from_fs = true;
 583         }
 584
 585         return NT_STATUS_OK;
 586
 587 fail:
 588         TALLOC_FREE(psd);
 589         TALLOC_FREE(psd_blob);
 590         TALLOC_FREE(psd_fs);
 591         TALLOC_FREE(sys_acl_blob_description);
 592         TALLOC_FREE(sys_acl_blob.data);
 593         return status;
 594 }
 595
 596 static NTSTATUS stat_fsp_or_smb_fname(vfs_handle_struct *handle,
 597                                       files_struct *fsp,
 598                                       const struct smb_filename *smb_fname,
 599                                       SMB_STRUCT_STAT *sbuf,
 600                                       SMB_STRUCT_STAT **psbuf)
 601 {
 602         NTSTATUS status;
 603         int ret;
 604
 605         if (fsp) {
 606                 status = vfs_stat_fsp(fsp);
 607                 if (!NT_STATUS_IS_OK(status)) {
 608                         return status;
 609                 }
 610                 *psbuf = &fsp->fsp_name->st;
 611         } else {
 612                 /*
 613                  * https://bugzilla.samba.org/show_bug.cgi?id=11249
 614                  *
 615                  * We are currently guaranteed that 'name' here is a
 616                  * smb_fname->base_name, which *cannot* contain a stream name
 617                  * (':'). vfs_stat_smb_fname() splits a name into a base name +
 618                  * stream name, which when we get here we know we've already
 619                  * done.  So we have to call the stat or lstat VFS calls
 620                  * directly here. Else, a base_name that contains a ':' (from a
 621                  * demangled name) will get split again.
 622                  *
 623                  * FIXME.
 624                  * This uglyness will go away once smb_fname is fully plumbed
 625                  * through the VFS.
 626                  */
 627                 ret = vfs_stat_smb_basename(handle->conn,
 628                                             smb_fname,
 629                                             sbuf);
 630                 if (ret == -1) {
 631                         return map_nt_error_from_unix(errno);
 632                 }
 633         }
 634
 635         return NT_STATUS_OK;
 636 }
 637
 638 /*******************************************************************
 639  Pull a DATA_BLOB from an xattr given an fsp.
 640  If the hash doesn't match, or doesn't exist - return the underlying
 641  filesystem sd.
 642 *******************************************************************/
 643
 644 NTSTATUS fget_nt_acl_common(
 645         NTSTATUS (*fget_acl_blob_fn)(TALLOC_CTX *ctx,
 646                                     vfs_handle_struct *handle,
 647                                     files_struct *fsp,
 648                                     DATA_BLOB *pblob),
 649         vfs_handle_struct *handle,
 650         files_struct *fsp,
 651         uint32_t security_info,
 652         TALLOC_CTX *mem_ctx,
 653         struct security_descriptor **ppdesc)
 654 {
 655         DATA_BLOB blob = data_blob_null;
 656         NTSTATUS status;
 657         struct security_descriptor *psd = NULL;
 658         const struct smb_filename *smb_fname = fsp->fsp_name;
 659         bool psd_is_from_fs = false;
 660         struct acl_common_config *config = NULL;
 661
 662         SMB_VFS_HANDLE_GET_DATA(handle, config,
 663                                 struct acl_common_config,
 664                                 return NT_STATUS_UNSUCCESSFUL);
 665
 666         DBG_DEBUG("name=%s\n", smb_fname->base_name);
 667
 668         status = fget_acl_blob_fn(mem_ctx, handle, fsp, &blob);
 669         if (NT_STATUS_IS_OK(status)) {
 670                 status = validate_nt_acl_blob(mem_ctx,
 671                                               handle,
 672                                               fsp,
 673                                               smb_fname,
 674                                               &blob,
 675                                               &psd,
 676                                               &psd_is_from_fs);
 677                 TALLOC_FREE(blob.data);
 678                 if (!NT_STATUS_IS_OK(status)) {
 679                         DBG_DEBUG("ACL validation for [%s] failed\n",
 680                                   smb_fname->base_name);
 681                         goto fail;
 682                 }
 683         }
 684
 685         if (psd == NULL) {
 686                 /* Get the full underlying sd, as we failed to get the
 687                  * blob for the hash, or the revision/hash type wasn't
 688                  * known */
 689
 690                 if (config->ignore_system_acls) {
 691                         status = vfs_stat_fsp(fsp);
 692                         if (!NT_STATUS_IS_OK(status)) {
 693                                 goto fail;
 694                         }
 695
 696                         status = make_default_filesystem_acl(
 697                                 mem_ctx,
 698                                 config->default_acl_style,
 699                                 smb_fname->base_name,
 700                                 &fsp->fsp_name->st,
 701                                 &psd);
 702                         if (!NT_STATUS_IS_OK(status)) {
 703                                 goto fail;
 704                         }
 705                 } else {
 706                         status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
 707                                                           fsp,
 708                                                           security_info,
 709                                                           mem_ctx,
 710                                                           &psd);
 711
 712                         if (!NT_STATUS_IS_OK(status)) {
 713                                 DBG_DEBUG("get_next_acl for file %s "
 714                                           "returned %s\n",
 715                                           smb_fname->base_name,
 716                                           nt_errstr(status));
 717                                 goto fail;
 718                         }
 719
 720                         psd_is_from_fs = true;
 721                 }
 722         }
 723
 724         if (psd_is_from_fs) {
 725                 status = vfs_stat_fsp(fsp);
 726                 if (!NT_STATUS_IS_OK(status)) {
 727                         goto fail;
 728                 }
 729
 730                 /*
 731                  * We're returning the underlying ACL from the
 732                  * filesystem. If it's a directory, and has no
 733                  * inheritable ACE entries we have to fake them.
 734                  */
 735
 736                 if (fsp->fsp_flags.is_directory &&
 737                                 !sd_has_inheritable_components(psd, true)) {
 738                         status = add_directory_inheritable_components(
 739                                 handle,
 740                                 smb_fname->base_name,
 741                                 &fsp->fsp_name->st,
 742                                 psd);
 743                         if (!NT_STATUS_IS_OK(status)) {
 744                                 goto fail;
 745                         }
 746                 }
 747
 748                 /*
 749                  * The underlying POSIX module always sets the
 750                  * ~SEC_DESC_DACL_PROTECTED bit, as ACLs can't be inherited in
 751                  * this way under POSIX. Remove it for Windows-style ACLs.
 752                  */
 753                 psd->type &= ~SEC_DESC_DACL_PROTECTED;
 754         }
 755
 756         if (!(security_info & SECINFO_OWNER)) {
 757                 psd->owner_sid = NULL;
 758         }
 759         if (!(security_info & SECINFO_GROUP)) {
 760                 psd->group_sid = NULL;
 761         }
 762         if (!(security_info & SECINFO_DACL)) {
 763                 psd->type &= ~SEC_DESC_DACL_PRESENT;
 764                 psd->dacl = NULL;
 765         }
 766         if (!(security_info & SECINFO_SACL)) {
 767                 psd->type &= ~SEC_DESC_SACL_PRESENT;
 768                 psd->sacl = NULL;
 769         }
 770
 771         if (DEBUGLEVEL >= 10) {
 772                 DBG_DEBUG("returning acl for %s is:\n",
 773                           smb_fname->base_name);
 774                 NDR_PRINT_DEBUG(security_descriptor, psd);
 775         }
 776
 777         *ppdesc = psd;
 778
 779         return NT_STATUS_OK;
 780
 781 fail:
 782         TALLOC_FREE(psd);
 783         return status;
 784 }
 785
 786 /*******************************************************************
 787  Pull a DATA_BLOB from an xattr given a pathname.
 788  If the hash doesn't match, or doesn't exist - return the underlying
 789  filesystem sd.
 790 *******************************************************************/
 791
 792 NTSTATUS get_nt_acl_common(
 793         NTSTATUS (*get_acl_blob_fn)(TALLOC_CTX *ctx,
 794                                     vfs_handle_struct *handle,
 795                                     files_struct *fsp,
 796                                     const struct smb_filename *smb_fname,
 797                                     DATA_BLOB *pblob),
 798         vfs_handle_struct *handle,
 799         files_struct *fsp,
 800         const struct smb_filename *smb_fname_in,
 801         uint32_t security_info,
 802         TALLOC_CTX *mem_ctx,
 803         struct security_descriptor **ppdesc)
 804 {
 805         DATA_BLOB blob = data_blob_null;
 806         NTSTATUS status;
 807         struct security_descriptor *psd = NULL;
 808         const struct smb_filename *smb_fname = NULL;
 809         bool psd_is_from_fs = false;
 810         struct acl_common_config *config = NULL;
 811
 812         SMB_VFS_HANDLE_GET_DATA(handle, config,
 813                                 struct acl_common_config,
 814                                 return NT_STATUS_UNSUCCESSFUL);
 815
 816         if (fsp && smb_fname_in == NULL) {
 817                 smb_fname = fsp->fsp_name;
 818         } else {
 819                 smb_fname = smb_fname_in;
 820         }
 821
 822         DBG_DEBUG("name=%s\n", smb_fname->base_name);
 823
 824         status = get_acl_blob_fn(mem_ctx, handle, fsp, smb_fname, &blob);
 825         if (NT_STATUS_IS_OK(status)) {
 826                 status = validate_nt_acl_blob(mem_ctx,
 827                                               handle,
 828                                               fsp,
 829                                               smb_fname,
 830                                               &blob,
 831                                               &psd,
 832                                               &psd_is_from_fs);
 833                 TALLOC_FREE(blob.data);
 834                 if (!NT_STATUS_IS_OK(status)) {
 835                         DBG_DEBUG("ACL validation for [%s] failed\n",
 836                                   smb_fname->base_name);
 837                         goto fail;
 838                 }
 839         }
 840
 841         if (psd == NULL) {
 842                 /* Get the full underlying sd, as we failed to get the
 843                  * blob for the hash, or the revision/hash type wasn't
 844                  * known */
 845
 846                 if (config->ignore_system_acls) {
 847                         SMB_STRUCT_STAT sbuf;
 848                         SMB_STRUCT_STAT *psbuf = &sbuf;
 849
 850                         status = stat_fsp_or_smb_fname(handle, fsp, smb_fname,
 851                                                        &sbuf, &psbuf);
 852                         if (!NT_STATUS_IS_OK(status)) {
 853                                 goto fail;
 854                         }
 855
 856                         status = make_default_filesystem_acl(
 857                                 mem_ctx,
 858                                 config->default_acl_style,
 859                                 smb_fname->base_name,
 860                                 psbuf,
 861                                 &psd);
 862                         if (!NT_STATUS_IS_OK(status)) {
 863                                 goto fail;
 864                         }
 865                 } else {
 866                         if (fsp) {
 867                                 status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
 868                                                                   fsp,
 869                                                                   security_info,
 870                                                                   mem_ctx,
 871                                                                   &psd);
 872                         } else {
 873                                 status = SMB_VFS_NEXT_GET_NT_ACL(handle,
 874                                                                  smb_fname,
 875                                                                  security_info,
 876                                                                  mem_ctx,
 877                                                                  &psd);
 878                         }
 879
 880                         if (!NT_STATUS_IS_OK(status)) {
 881                                 DBG_DEBUG("get_next_acl for file %s "
 882                                           "returned %s\n",
 883                                           smb_fname->base_name,
 884                                           nt_errstr(status));
 885                                 goto fail;
 886                         }
 887
 888                         psd_is_from_fs = true;
 889                 }
 890         }
 891
 892         if (psd_is_from_fs) {
 893                 SMB_STRUCT_STAT sbuf;
 894                 SMB_STRUCT_STAT *psbuf = &sbuf;
 895                 bool is_directory = false;
 896
 897                 /*
 898                  * We're returning the underlying ACL from the
 899                  * filesystem. If it's a directory, and has no
 900                  * inheritable ACE entries we have to fake them.
 901                  */
 902
 903                 status = stat_fsp_or_smb_fname(handle, fsp, smb_fname,
 904                                                &sbuf, &psbuf);
 905                 if (!NT_STATUS_IS_OK(status)) {
 906                         goto fail;
 907                 }
 908
 909                 is_directory = S_ISDIR(psbuf->st_ex_mode);
 910
 911                 if (is_directory && !sd_has_inheritable_components(psd, true)) {
 912                         status = add_directory_inheritable_components(
 913                                 handle,
 914                                 smb_fname->base_name,
 915                                 psbuf,
 916                                 psd);
 917                         if (!NT_STATUS_IS_OK(status)) {
 918                                 goto fail;
 919                         }
 920                 }
 921
 922                 /*
 923                  * The underlying POSIX module always sets the
 924                  * ~SEC_DESC_DACL_PROTECTED bit, as ACLs can't be inherited in
 925                  * this way under POSIX. Remove it for Windows-style ACLs.
 926                  */
 927                 psd->type &= ~SEC_DESC_DACL_PROTECTED;
 928         }
 929
 930         if (!(security_info & SECINFO_OWNER)) {
 931                 psd->owner_sid = NULL;
 932         }
 933         if (!(security_info & SECINFO_GROUP)) {
 934                 psd->group_sid = NULL;
 935         }
 936         if (!(security_info & SECINFO_DACL)) {
 937                 psd->type &= ~SEC_DESC_DACL_PRESENT;
 938                 psd->dacl = NULL;
 939         }
 940         if (!(security_info & SECINFO_SACL)) {
 941                 psd->type &= ~SEC_DESC_SACL_PRESENT;
 942                 psd->sacl = NULL;
 943         }
 944
 945         if (DEBUGLEVEL >= 10) {
 946                 DBG_DEBUG("returning acl for %s is:\n",
 947                           smb_fname->base_name);
 948                 NDR_PRINT_DEBUG(security_descriptor, psd);
 949         }
 950
 951         *ppdesc = psd;
 952
 953         return NT_STATUS_OK;
 954
 955 fail:
 956         TALLOC_FREE(psd);
 957         return status;
 958 }
 959
 960 /*********************************************************************
 961  Set the underlying ACL (e.g. POSIX ACLS, POSIX owner, etc)
 962 *********************************************************************/
 963 static NTSTATUS set_underlying_acl(vfs_handle_struct *handle, files_struct *fsp,
 964                                    struct security_descriptor *psd,
 965                                    uint32_t security_info_sent,
 966                                    bool chown_needed)
 967 {
 968         NTSTATUS status;
 969         const struct security_token *token = NULL;
 970         struct dom_sid_buf buf;
 971
 972         status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
 973         if (!NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED)) {
 974                 return status;
 975         }
 976
 977         /* We got access denied here. If we're already root,
 978            or we didn't need to do a chown, or the fsp isn't
 979            open with WRITE_OWNER access, just return. */
 980         if (get_current_uid(handle->conn) == 0 || chown_needed == false ||
 981             !(fsp->access_mask & SEC_STD_WRITE_OWNER)) {
 982                 return NT_STATUS_ACCESS_DENIED;
 983         }
 984
 985         /*
 986          * Only allow take-ownership, not give-ownership. That's the way Windows
 987          * implements SEC_STD_WRITE_OWNER. MS-FSA 2.1.5.16 just states: If
 988          * InputBuffer.OwnerSid is not a valid owner SID for a file in the
 989          * objectstore, as determined in an implementation specific manner, the
 990          * object store MUST return STATUS_INVALID_OWNER.
 991          */
 992         token = get_current_nttok(fsp->conn);
 993         if (!security_token_is_sid(token, psd->owner_sid)) {
 994                 return NT_STATUS_INVALID_OWNER;
 995         }
 996
 997         DBG_DEBUG("overriding chown on file %s for sid %s\n",
 998                   fsp_str_dbg(fsp),
 999                   dom_sid_str_buf(psd->owner_sid, &buf));
1000
1001         /* Ok, we failed to chown and we have
1002            SEC_STD_WRITE_OWNER access - override. */
1003         become_root();
1004         status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
1005         unbecome_root();
1006
1007         return status;
1008 }
1009
1010 /*********************************************************************
1011  Store a v3 security descriptor
1012 *********************************************************************/
1013 static NTSTATUS store_v3_blob(
1014         NTSTATUS (*store_acl_blob_fsp_fn)(vfs_handle_struct *handle,
1015                                           files_struct *fsp,
1016                                           DATA_BLOB *pblob),
1017         vfs_handle_struct *handle, files_struct *fsp,
1018         struct security_descriptor *psd,
1019         struct security_descriptor *pdesc_next,
1020         uint8_t hash[XATTR_SD_HASH_SIZE])
1021 {
1022         NTSTATUS status;
1023         DATA_BLOB blob;
1024
1025         if (DEBUGLEVEL >= 10) {
1026                 DBG_DEBUG("storing xattr sd for file %s\n",
1027                           fsp_str_dbg(fsp));
1028                 NDR_PRINT_DEBUG(
1029                     security_descriptor,
1030                     discard_const_p(struct security_descriptor, psd));
1031
1032                 if (pdesc_next != NULL) {
1033                         DBG_DEBUG("storing xattr sd based on \n");
1034                         NDR_PRINT_DEBUG(
1035                             security_descriptor,
1036                             discard_const_p(struct security_descriptor,
1037                                             pdesc_next));
1038                 } else {
1039                         DBG_DEBUG("ignoring underlying sd\n");
1040                 }
1041         }
1042         status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
1043         if (!NT_STATUS_IS_OK(status)) {
1044                 DBG_DEBUG("create_acl_blob failed\n");
1045                 return status;
1046         }
1047
1048         status = store_acl_blob_fsp_fn(handle, fsp, &blob);
1049         return status;
1050 }
1051
1052 /*********************************************************************
1053  Store a security descriptor given an fsp.
1054 *********************************************************************/
1055
1056 NTSTATUS fset_nt_acl_common(
1057         NTSTATUS (*get_acl_blob_fn)(TALLOC_CTX *ctx,
1058                                     vfs_handle_struct *handle,
1059                                     files_struct *fsp,
1060                                     const struct smb_filename *smb_fname,
1061                                     DATA_BLOB *pblob),
1062         NTSTATUS (*store_acl_blob_fsp_fn)(vfs_handle_struct *handle,
1063                                           files_struct *fsp,
1064                                           DATA_BLOB *pblob),
1065         const char *module_name,
1066         vfs_handle_struct *handle, files_struct *fsp,
1067         uint32_t security_info_sent,
1068         const struct security_descriptor *orig_psd)
1069 {
1070         NTSTATUS status;
1071         int ret;
1072         DATA_BLOB blob, sys_acl_blob;
1073         struct security_descriptor *pdesc_next = NULL;
1074         struct security_descriptor *psd = NULL;
1075         uint8_t hash[XATTR_SD_HASH_SIZE];
1076         uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE];
1077         bool chown_needed = false;
1078         char *sys_acl_description;
1079         TALLOC_CTX *frame = talloc_stackframe();
1080         bool ignore_file_system_acl = lp_parm_bool(
1081             SNUM(handle->conn), module_name, "ignore system acls", false);
1082
1083         if (DEBUGLEVEL >= 10) {
1084                 DBG_DEBUG("incoming sd for file %s\n", fsp_str_dbg(fsp));
1085                 NDR_PRINT_DEBUG(security_descriptor,
1086                         discard_const_p(struct security_descriptor, orig_psd));
1087         }
1088
1089         status = get_nt_acl_common(get_acl_blob_fn, handle, fsp,
1090                         NULL,
1091                         SECINFO_OWNER|SECINFO_GROUP|SECINFO_DACL|SECINFO_SACL,
1092                                      frame,
1093                         &psd);
1094
1095         if (!NT_STATUS_IS_OK(status)) {
1096                 TALLOC_FREE(frame);
1097                 return status;
1098         }
1099
1100         psd->revision = orig_psd->revision;
1101         if (security_info_sent & SECINFO_DACL) {
1102                 psd->type = orig_psd->type;
1103                 /* All our SD's are self relative. */
1104                 psd->type |= SEC_DESC_SELF_RELATIVE;
1105         }
1106
1107         if ((security_info_sent & SECINFO_OWNER) && (orig_psd->owner_sid != NULL)) {
1108                 if (!dom_sid_equal(orig_psd->owner_sid, psd->owner_sid)) {
1109                         /* We're changing the owner. */
1110                         chown_needed = true;
1111                 }
1112                 psd->owner_sid = orig_psd->owner_sid;
1113         }
1114         if ((security_info_sent & SECINFO_GROUP) && (orig_psd->group_sid != NULL)) {
1115                 if (!dom_sid_equal(orig_psd->group_sid, psd->group_sid)) {
1116                         /* We're changing the group. */
1117                         chown_needed = true;
1118                 }
1119                 psd->group_sid = orig_psd->group_sid;
1120         }
1121         if (security_info_sent & SECINFO_DACL) {
1122                 if (security_descriptor_with_ms_nfs(orig_psd)) {
1123                         /*
1124                          * If the sd contains a MS NFS SID, do
1125                          * nothing, it's a chmod() request from OS X
1126                          * with AAPL context.
1127                          */
1128                         TALLOC_FREE(frame);
1129                         return NT_STATUS_OK;
1130                 }
1131                 psd->dacl = orig_psd->dacl;
1132                 psd->type |= SEC_DESC_DACL_PRESENT;
1133         }
1134         if (security_info_sent & SECINFO_SACL) {
1135                 psd->sacl = orig_psd->sacl;
1136                 psd->type |= SEC_DESC_SACL_PRESENT;
1137         }
1138
1139         if (ignore_file_system_acl) {
1140                 if (chown_needed) {
1141                         /* send only ownership stuff to lower layer */
1142                         security_info_sent &= (SECINFO_OWNER | SECINFO_GROUP);
1143                         status = set_underlying_acl(handle, fsp, psd,
1144                                                     security_info_sent, true);
1145                         if (!NT_STATUS_IS_OK(status)) {
1146                                 TALLOC_FREE(frame);
1147                                 return status;
1148                         }
1149                 }
1150                 ZERO_ARRAY(hash);
1151                 status = store_v3_blob(store_acl_blob_fsp_fn, handle, fsp, psd,
1152                                        NULL, hash);
1153
1154                 TALLOC_FREE(frame);
1155                 return status;
1156         }
1157
1158         status = set_underlying_acl(handle, fsp, psd, security_info_sent,
1159                                     chown_needed);
1160         if (!NT_STATUS_IS_OK(status)) {
1161                 TALLOC_FREE(frame);
1162                 return status;
1163         }
1164
1165         /* Get the full underlying sd, then hash. */
1166         status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
1167                                           fsp,
1168                                           HASH_SECURITY_INFO,
1169                                           frame,
1170                                           &pdesc_next);
1171
1172         if (!NT_STATUS_IS_OK(status)) {
1173                 TALLOC_FREE(frame);
1174                 return status;
1175         }
1176
1177         status = hash_sd_sha256(pdesc_next, hash);
1178         if (!NT_STATUS_IS_OK(status)) {
1179                 TALLOC_FREE(frame);
1180                 return status;
1181         }
1182
1183         /* Get the full underlying sd, then hash. */
1184         ret = SMB_VFS_NEXT_SYS_ACL_BLOB_GET_FD(handle,
1185                                                fsp,
1186                                                frame,
1187                                                &sys_acl_description,
1188                                                &sys_acl_blob);
1189
1190         /* If we fail to get the ACL blob (for some reason) then this
1191          * is not fatal, we just work based on the NT ACL only */
1192         if (ret != 0) {
1193                 status = store_v3_blob(store_acl_blob_fsp_fn, handle, fsp, psd,
1194                                        pdesc_next, hash);
1195
1196                 TALLOC_FREE(frame);
1197                 return status;
1198         }
1199
1200         status = hash_blob_sha256(sys_acl_blob, sys_acl_hash);
1201         if (!NT_STATUS_IS_OK(status)) {
1202                 TALLOC_FREE(frame);
1203                 return status;
1204         }
1205
1206         if (DEBUGLEVEL >= 10) {
1207                 DBG_DEBUG("storing xattr sd for file %s based on system ACL\n",
1208                           fsp_str_dbg(fsp));
1209                 NDR_PRINT_DEBUG(security_descriptor,
1210                                 discard_const_p(struct security_descriptor, psd));
1211
1212                 DBG_DEBUG("storing hash in xattr sd based on system ACL and:\n");
1213                 NDR_PRINT_DEBUG(security_descriptor,
1214                                 discard_const_p(struct security_descriptor, pdesc_next));
1215         }
1216
1217         /* We store hashes of both the sys ACL blob and the NT
1218          * security desciptor mapped from that ACL so as to improve
1219          * our chances against some inadvertant change breaking the
1220          * hash used */
1221         status = create_sys_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash,
1222                                      sys_acl_description, sys_acl_hash);
1223         if (!NT_STATUS_IS_OK(status)) {
1224                 DBG_DEBUG("create_sys_acl_blob failed\n");
1225                 TALLOC_FREE(frame);
1226                 return status;
1227         }
1228
1229         status = store_acl_blob_fsp_fn(handle, fsp, &blob);
1230
1231         TALLOC_FREE(frame);
1232         return status;
1233 }
1234
1235 static int acl_common_remove_object(vfs_handle_struct *handle,
1236                                         const struct smb_filename *smb_fname,
1237                                         bool is_directory)
1238 {
1239         connection_struct *conn = handle->conn;
1240         struct file_id id;
1241         files_struct *fsp = NULL;
1242         int ret = 0;
1243         struct smb_filename *local_fname = NULL;
1244         struct smb_filename *parent_dir_fname = NULL;
1245         int saved_errno = 0;
1246         struct smb_filename *saved_dir_fname = NULL;
1247         bool ok;
1248
1249         saved_dir_fname = vfs_GetWd(talloc_tos(),conn);
1250         if (saved_dir_fname == NULL) {
1251                 saved_errno = errno;
1252                 goto out;
1253         }
1254
1255         ok = parent_smb_fname(talloc_tos(),
1256                               smb_fname,
1257                               &parent_dir_fname,
1258                               &local_fname);
1259         if (!ok) {
1260                 saved_errno = ENOMEM;
1261                 goto out;
1262         }
1263
1264         DBG_DEBUG("removing %s %s/%s\n", is_directory ? "directory" : "file",
1265                   smb_fname_str_dbg(parent_dir_fname),
1266                   smb_fname_str_dbg(local_fname));
1267
1268         /* cd into the parent dir to pin it. */
1269         ret = vfs_ChDir(conn, parent_dir_fname);
1270         if (ret == -1) {
1271                 saved_errno = errno;
1272                 goto out;
1273         }
1274
1275         /* Must use lstat here. */
1276         ret = SMB_VFS_LSTAT(conn, local_fname);
1277         if (ret == -1) {
1278                 saved_errno = errno;
1279                 goto out;
1280         }
1281
1282         /* Ensure we have this file open with DELETE access. */
1283         id = vfs_file_id_from_sbuf(conn, &local_fname->st);
1284         for (fsp = file_find_di_first(conn->sconn, id); fsp;
1285                      fsp = file_find_di_next(fsp)) {
1286                 if (fsp->access_mask & DELETE_ACCESS &&
1287                     fsp->fsp_flags.delete_on_close)
1288                 {
1289                         /* We did open this for delete,
1290                          * allow the delete as root.
1291                          */
1292                         break;
1293                 }
1294         }
1295
1296         if (!fsp) {
1297                 DBG_DEBUG("%s %s/%s not an open file\n",
1298                           is_directory ? "directory" : "file",
1299                           smb_fname_str_dbg(parent_dir_fname),
1300                           smb_fname_str_dbg(local_fname));
1301                 saved_errno = EACCES;
1302                 goto out;
1303         }
1304
1305         become_root();
1306         if (is_directory) {
1307                 ret = SMB_VFS_NEXT_UNLINKAT(handle,
1308                                 conn->cwd_fsp,
1309                                 local_fname,
1310                                 AT_REMOVEDIR);
1311         } else {
1312                 ret = SMB_VFS_NEXT_UNLINKAT(handle,
1313                                 conn->cwd_fsp,
1314                                 local_fname,
1315                                 0);
1316         }
1317         unbecome_root();
1318
1319         if (ret == -1) {
1320                 saved_errno = errno;
1321         }
1322
1323   out:
1324
1325         TALLOC_FREE(parent_dir_fname);
1326
1327         if (saved_dir_fname) {
1328                 vfs_ChDir(conn, saved_dir_fname);
1329                 TALLOC_FREE(saved_dir_fname);
1330         }
1331         if (saved_errno) {
1332                 errno = saved_errno;
1333         }
1334         return ret;
1335 }
1336
1337 int rmdir_acl_common(struct vfs_handle_struct *handle,
1338                 struct files_struct *dirfsp,
1339                 const struct smb_filename *smb_fname)
1340 {
1341         int ret;
1342
1343         /* Try the normal rmdir first. */
1344         ret = SMB_VFS_NEXT_UNLINKAT(handle,
1345                         dirfsp,
1346                         smb_fname,
1347                         AT_REMOVEDIR);
1348         if (ret == 0) {
1349                 return 0;
1350         }
1351         if (errno == EACCES || errno == EPERM) {
1352                 /* Failed due to access denied,
1353                    see if we need to root override. */
1354                 return acl_common_remove_object(handle,
1355                                                 smb_fname,
1356                                                 true);
1357         }
1358
1359         DBG_DEBUG("unlink of %s failed %s\n",
1360                   smb_fname->base_name,
1361                   strerror(errno));
1362         return -1;
1363 }
1364
1365 int unlink_acl_common(struct vfs_handle_struct *handle,
1366                         struct files_struct *dirfsp,
1367                         const struct smb_filename *smb_fname,
1368                         int flags)
1369 {
1370         int ret;
1371
1372         /* Try the normal unlink first. */
1373         ret = SMB_VFS_NEXT_UNLINKAT(handle,
1374                                 dirfsp,
1375                                 smb_fname,
1376                                 flags);
1377         if (ret == 0) {
1378                 return 0;
1379         }
1380         if (errno == EACCES || errno == EPERM) {
1381                 /* Failed due to access denied,
1382                    see if we need to root override. */
1383
1384                 /* Don't do anything fancy for streams. */
1385                 if (smb_fname->stream_name) {
1386                         return -1;
1387                 }
1388                 return acl_common_remove_object(handle,
1389                                         smb_fname,
1390                                         false);
1391         }
1392
1393         DBG_DEBUG("unlink of %s failed %s\n",
1394                   smb_fname->base_name,
1395                   strerror(errno));
1396         return -1;
1397 }
1398
1399 int chmod_acl_module_common(struct vfs_handle_struct *handle,
1400                             const struct smb_filename *smb_fname,
1401                             mode_t mode)
1402 {
1403         if (smb_fname->flags & SMB_FILENAME_POSIX_PATH) {
1404                 /* Only allow this on POSIX pathnames. */
1405                 return SMB_VFS_NEXT_CHMOD(handle, smb_fname, mode);
1406         }
1407         return 0;
1408 }
1409
1410 int fchmod_acl_module_common(struct vfs_handle_struct *handle,
1411                              struct files_struct *fsp, mode_t mode)
1412 {
1413         if (fsp->posix_flags & FSP_POSIX_FLAGS_OPEN) {
1414                 /* Only allow this on POSIX opens. */
1415                 return SMB_VFS_NEXT_FCHMOD(handle, fsp, mode);
1416         }
1417         return 0;
1418 }