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 /*******************************************************************
 597  Pull a DATA_BLOB from an xattr given an fsp.
 598  If the hash doesn't match, or doesn't exist - return the underlying
 599  filesystem sd.
 600 *******************************************************************/
 601
 602 NTSTATUS fget_nt_acl_common(
 603         NTSTATUS (*fget_acl_blob_fn)(TALLOC_CTX *ctx,
 604                                     vfs_handle_struct *handle,
 605                                     files_struct *fsp,
 606                                     DATA_BLOB *pblob),
 607         vfs_handle_struct *handle,
 608         files_struct *fsp,
 609         uint32_t security_info,
 610         TALLOC_CTX *mem_ctx,
 611         struct security_descriptor **ppdesc)
 612 {
 613         DATA_BLOB blob = data_blob_null;
 614         NTSTATUS status;
 615         struct security_descriptor *psd = NULL;
 616         const struct smb_filename *smb_fname = fsp->fsp_name;
 617         bool psd_is_from_fs = false;
 618         struct acl_common_config *config = NULL;
 619
 620         SMB_VFS_HANDLE_GET_DATA(handle, config,
 621                                 struct acl_common_config,
 622                                 return NT_STATUS_UNSUCCESSFUL);
 623
 624         DBG_DEBUG("name=%s\n", smb_fname->base_name);
 625
 626         status = fget_acl_blob_fn(mem_ctx, handle, fsp, &blob);
 627         if (NT_STATUS_IS_OK(status)) {
 628                 status = validate_nt_acl_blob(mem_ctx,
 629                                               handle,
 630                                               fsp,
 631                                               smb_fname,
 632                                               &blob,
 633                                               &psd,
 634                                               &psd_is_from_fs);
 635                 TALLOC_FREE(blob.data);
 636                 if (!NT_STATUS_IS_OK(status)) {
 637                         DBG_DEBUG("ACL validation for [%s] failed\n",
 638                                   smb_fname->base_name);
 639                         goto fail;
 640                 }
 641         }
 642
 643         if (psd == NULL) {
 644                 /* Get the full underlying sd, as we failed to get the
 645                  * blob for the hash, or the revision/hash type wasn't
 646                  * known */
 647
 648                 if (config->ignore_system_acls) {
 649                         status = vfs_stat_fsp(fsp);
 650                         if (!NT_STATUS_IS_OK(status)) {
 651                                 goto fail;
 652                         }
 653
 654                         status = make_default_filesystem_acl(
 655                                 mem_ctx,
 656                                 config->default_acl_style,
 657                                 smb_fname->base_name,
 658                                 &fsp->fsp_name->st,
 659                                 &psd);
 660                         if (!NT_STATUS_IS_OK(status)) {
 661                                 goto fail;
 662                         }
 663                 } else {
 664                         status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
 665                                                           fsp,
 666                                                           security_info,
 667                                                           mem_ctx,
 668                                                           &psd);
 669
 670                         if (!NT_STATUS_IS_OK(status)) {
 671                                 DBG_DEBUG("get_next_acl for file %s "
 672                                           "returned %s\n",
 673                                           smb_fname->base_name,
 674                                           nt_errstr(status));
 675                                 goto fail;
 676                         }
 677
 678                         psd_is_from_fs = true;
 679                 }
 680         }
 681
 682         if (psd_is_from_fs) {
 683                 status = vfs_stat_fsp(fsp);
 684                 if (!NT_STATUS_IS_OK(status)) {
 685                         goto fail;
 686                 }
 687
 688                 /*
 689                  * We're returning the underlying ACL from the
 690                  * filesystem. If it's a directory, and has no
 691                  * inheritable ACE entries we have to fake them.
 692                  */
 693
 694                 if (fsp->fsp_flags.is_directory &&
 695                                 !sd_has_inheritable_components(psd, true)) {
 696                         status = add_directory_inheritable_components(
 697                                 handle,
 698                                 smb_fname->base_name,
 699                                 &fsp->fsp_name->st,
 700                                 psd);
 701                         if (!NT_STATUS_IS_OK(status)) {
 702                                 goto fail;
 703                         }
 704                 }
 705
 706                 /*
 707                  * The underlying POSIX module always sets the
 708                  * ~SEC_DESC_DACL_PROTECTED bit, as ACLs can't be inherited in
 709                  * this way under POSIX. Remove it for Windows-style ACLs.
 710                  */
 711                 psd->type &= ~SEC_DESC_DACL_PROTECTED;
 712         }
 713
 714         if (!(security_info & SECINFO_OWNER)) {
 715                 psd->owner_sid = NULL;
 716         }
 717         if (!(security_info & SECINFO_GROUP)) {
 718                 psd->group_sid = NULL;
 719         }
 720         if (!(security_info & SECINFO_DACL)) {
 721                 psd->type &= ~SEC_DESC_DACL_PRESENT;
 722                 psd->dacl = NULL;
 723         }
 724         if (!(security_info & SECINFO_SACL)) {
 725                 psd->type &= ~SEC_DESC_SACL_PRESENT;
 726                 psd->sacl = NULL;
 727         }
 728
 729         if (DEBUGLEVEL >= 10) {
 730                 DBG_DEBUG("returning acl for %s is:\n",
 731                           smb_fname->base_name);
 732                 NDR_PRINT_DEBUG(security_descriptor, psd);
 733         }
 734
 735         *ppdesc = psd;
 736
 737         return NT_STATUS_OK;
 738
 739 fail:
 740         TALLOC_FREE(psd);
 741         return status;
 742 }
 743
 744 /*******************************************************************
 745  Pull a DATA_BLOB from an xattr given a pathname.
 746  If the hash doesn't match, or doesn't exist - return the underlying
 747  filesystem sd.
 748 *******************************************************************/
 749
 750 NTSTATUS get_nt_acl_common(
 751         NTSTATUS (*get_acl_blob_fn)(TALLOC_CTX *ctx,
 752                                     vfs_handle_struct *handle,
 753                                     const struct smb_filename *smb_fname,
 754                                     DATA_BLOB *pblob),
 755         vfs_handle_struct *handle,
 756         const struct smb_filename *smb_fname_in,
 757         uint32_t security_info,
 758         TALLOC_CTX *mem_ctx,
 759         struct security_descriptor **ppdesc)
 760 {
 761         DATA_BLOB blob = data_blob_null;
 762         NTSTATUS status;
 763         struct security_descriptor *psd = NULL;
 764         bool psd_is_from_fs = false;
 765         struct acl_common_config *config = NULL;
 766
 767         SMB_VFS_HANDLE_GET_DATA(handle, config,
 768                                 struct acl_common_config,
 769                                 return NT_STATUS_UNSUCCESSFUL);
 770
 771         DBG_DEBUG("name=%s\n", smb_fname_in->base_name);
 772
 773         status = get_acl_blob_fn(mem_ctx, handle, smb_fname_in, &blob);
 774         if (NT_STATUS_IS_OK(status)) {
 775                 status = validate_nt_acl_blob(mem_ctx,
 776                                               handle,
 777                                               NULL,
 778                                               smb_fname_in,
 779                                               &blob,
 780                                               &psd,
 781                                               &psd_is_from_fs);
 782                 TALLOC_FREE(blob.data);
 783                 if (!NT_STATUS_IS_OK(status)) {
 784                         DBG_DEBUG("ACL validation for [%s] failed\n",
 785                                   smb_fname_in->base_name);
 786                         goto fail;
 787                 }
 788         }
 789
 790         if (psd == NULL) {
 791                 /* Get the full underlying sd, as we failed to get the
 792                  * blob for the hash, or the revision/hash type wasn't
 793                  * known */
 794
 795                 if (config->ignore_system_acls) {
 796                         SMB_STRUCT_STAT sbuf;
 797                         int ret;
 798
 799                         ret = vfs_stat_smb_basename(handle->conn,
 800                                         smb_fname_in,
 801                                         &sbuf);
 802                         if (ret == -1) {
 803                                 status = map_nt_error_from_unix(errno);
 804                                 goto fail;
 805                         }
 806
 807                         status = make_default_filesystem_acl(
 808                                 mem_ctx,
 809                                 config->default_acl_style,
 810                                 smb_fname_in->base_name,
 811                                 &sbuf,
 812                                 &psd);
 813                         if (!NT_STATUS_IS_OK(status)) {
 814                                 goto fail;
 815                         }
 816                 } else {
 817                         status = SMB_VFS_NEXT_GET_NT_ACL(handle,
 818                                                          smb_fname_in,
 819                                                          security_info,
 820                                                          mem_ctx,
 821                                                          &psd);
 822
 823                         if (!NT_STATUS_IS_OK(status)) {
 824                                 DBG_DEBUG("get_next_acl for file %s "
 825                                           "returned %s\n",
 826                                           smb_fname_in->base_name,
 827                                           nt_errstr(status));
 828                                 goto fail;
 829                         }
 830
 831                         psd_is_from_fs = true;
 832                 }
 833         }
 834
 835         if (psd_is_from_fs) {
 836                 SMB_STRUCT_STAT sbuf;
 837                 bool is_directory = false;
 838                 int ret;
 839
 840                 /*
 841                  * We're returning the underlying ACL from the
 842                  * filesystem. If it's a directory, and has no
 843                  * inheritable ACE entries we have to fake them.
 844                  */
 845
 846                 ret = vfs_stat_smb_basename(handle->conn,
 847                                 smb_fname_in,
 848                                 &sbuf);
 849                 if (ret == -1) {
 850                         status = map_nt_error_from_unix(errno);
 851                         goto fail;
 852                 }
 853
 854                 is_directory = S_ISDIR(sbuf.st_ex_mode);
 855
 856                 if (is_directory && !sd_has_inheritable_components(psd, true)) {
 857                         status = add_directory_inheritable_components(
 858                                 handle,
 859                                 smb_fname_in->base_name,
 860                                 &sbuf,
 861                                 psd);
 862                         if (!NT_STATUS_IS_OK(status)) {
 863                                 goto fail;
 864                         }
 865                 }
 866
 867                 /*
 868                  * The underlying POSIX module always sets the
 869                  * ~SEC_DESC_DACL_PROTECTED bit, as ACLs can't be inherited in
 870                  * this way under POSIX. Remove it for Windows-style ACLs.
 871                  */
 872                 psd->type &= ~SEC_DESC_DACL_PROTECTED;
 873         }
 874
 875         if (!(security_info & SECINFO_OWNER)) {
 876                 psd->owner_sid = NULL;
 877         }
 878         if (!(security_info & SECINFO_GROUP)) {
 879                 psd->group_sid = NULL;
 880         }
 881         if (!(security_info & SECINFO_DACL)) {
 882                 psd->type &= ~SEC_DESC_DACL_PRESENT;
 883                 psd->dacl = NULL;
 884         }
 885         if (!(security_info & SECINFO_SACL)) {
 886                 psd->type &= ~SEC_DESC_SACL_PRESENT;
 887                 psd->sacl = NULL;
 888         }
 889
 890         if (DEBUGLEVEL >= 10) {
 891                 DBG_DEBUG("returning acl for %s is:\n",
 892                           smb_fname_in->base_name);
 893                 NDR_PRINT_DEBUG(security_descriptor, psd);
 894         }
 895
 896         *ppdesc = psd;
 897
 898         return NT_STATUS_OK;
 899
 900 fail:
 901         TALLOC_FREE(psd);
 902         return status;
 903 }
 904
 905 /*********************************************************************
 906  Set the underlying ACL (e.g. POSIX ACLS, POSIX owner, etc)
 907 *********************************************************************/
 908 static NTSTATUS set_underlying_acl(vfs_handle_struct *handle, files_struct *fsp,
 909                                    struct security_descriptor *psd,
 910                                    uint32_t security_info_sent,
 911                                    bool chown_needed)
 912 {
 913         NTSTATUS status;
 914         const struct security_token *token = NULL;
 915         struct dom_sid_buf buf;
 916
 917         status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
 918         if (!NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED)) {
 919                 return status;
 920         }
 921
 922         /* We got access denied here. If we're already root,
 923            or we didn't need to do a chown, or the fsp isn't
 924            open with WRITE_OWNER access, just return. */
 925         if (get_current_uid(handle->conn) == 0 || chown_needed == false ||
 926             !(fsp->access_mask & SEC_STD_WRITE_OWNER)) {
 927                 return NT_STATUS_ACCESS_DENIED;
 928         }
 929
 930         /*
 931          * Only allow take-ownership, not give-ownership. That's the way Windows
 932          * implements SEC_STD_WRITE_OWNER. MS-FSA 2.1.5.16 just states: If
 933          * InputBuffer.OwnerSid is not a valid owner SID for a file in the
 934          * objectstore, as determined in an implementation specific manner, the
 935          * object store MUST return STATUS_INVALID_OWNER.
 936          */
 937         token = get_current_nttok(fsp->conn);
 938         if (!security_token_is_sid(token, psd->owner_sid)) {
 939                 return NT_STATUS_INVALID_OWNER;
 940         }
 941
 942         DBG_DEBUG("overriding chown on file %s for sid %s\n",
 943                   fsp_str_dbg(fsp),
 944                   dom_sid_str_buf(psd->owner_sid, &buf));
 945
 946         /* Ok, we failed to chown and we have
 947            SEC_STD_WRITE_OWNER access - override. */
 948         become_root();
 949         status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
 950         unbecome_root();
 951
 952         return status;
 953 }
 954
 955 /*********************************************************************
 956  Store a v3 security descriptor
 957 *********************************************************************/
 958 static NTSTATUS store_v3_blob(
 959         NTSTATUS (*store_acl_blob_fsp_fn)(vfs_handle_struct *handle,
 960                                           files_struct *fsp,
 961                                           DATA_BLOB *pblob),
 962         vfs_handle_struct *handle, files_struct *fsp,
 963         struct security_descriptor *psd,
 964         struct security_descriptor *pdesc_next,
 965         uint8_t hash[XATTR_SD_HASH_SIZE])
 966 {
 967         NTSTATUS status;
 968         DATA_BLOB blob;
 969
 970         if (DEBUGLEVEL >= 10) {
 971                 DBG_DEBUG("storing xattr sd for file %s\n",
 972                           fsp_str_dbg(fsp));
 973                 NDR_PRINT_DEBUG(
 974                     security_descriptor,
 975                     discard_const_p(struct security_descriptor, psd));
 976
 977                 if (pdesc_next != NULL) {
 978                         DBG_DEBUG("storing xattr sd based on \n");
 979                         NDR_PRINT_DEBUG(
 980                             security_descriptor,
 981                             discard_const_p(struct security_descriptor,
 982                                             pdesc_next));
 983                 } else {
 984                         DBG_DEBUG("ignoring underlying sd\n");
 985                 }
 986         }
 987         status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
 988         if (!NT_STATUS_IS_OK(status)) {
 989                 DBG_DEBUG("create_acl_blob failed\n");
 990                 return status;
 991         }
 992
 993         status = store_acl_blob_fsp_fn(handle, fsp, &blob);
 994         return status;
 995 }
 996
 997 /*********************************************************************
 998  Store a security descriptor given an fsp.
 999 *********************************************************************/
1000
1001 NTSTATUS fset_nt_acl_common(
1002         NTSTATUS (*fget_acl_blob_fn)(TALLOC_CTX *ctx,
1003                                     vfs_handle_struct *handle,
1004                                     files_struct *fsp,
1005                                     DATA_BLOB *pblob),
1006         NTSTATUS (*store_acl_blob_fsp_fn)(vfs_handle_struct *handle,
1007                                           files_struct *fsp,
1008                                           DATA_BLOB *pblob),
1009         const char *module_name,
1010         vfs_handle_struct *handle, files_struct *fsp,
1011         uint32_t security_info_sent,
1012         const struct security_descriptor *orig_psd)
1013 {
1014         NTSTATUS status;
1015         int ret;
1016         DATA_BLOB blob, sys_acl_blob;
1017         struct security_descriptor *pdesc_next = NULL;
1018         struct security_descriptor *psd = NULL;
1019         uint8_t hash[XATTR_SD_HASH_SIZE];
1020         uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE];
1021         bool chown_needed = false;
1022         char *sys_acl_description;
1023         TALLOC_CTX *frame = talloc_stackframe();
1024         bool ignore_file_system_acl = lp_parm_bool(
1025             SNUM(handle->conn), module_name, "ignore system acls", false);
1026
1027         if (DEBUGLEVEL >= 10) {
1028                 DBG_DEBUG("incoming sd for file %s\n", fsp_str_dbg(fsp));
1029                 NDR_PRINT_DEBUG(security_descriptor,
1030                         discard_const_p(struct security_descriptor, orig_psd));
1031         }
1032
1033         status = fget_nt_acl_common(fget_acl_blob_fn, handle, fsp,
1034                         SECINFO_OWNER|SECINFO_GROUP|SECINFO_DACL|SECINFO_SACL,
1035                                      frame,
1036                         &psd);
1037
1038         if (!NT_STATUS_IS_OK(status)) {
1039                 TALLOC_FREE(frame);
1040                 return status;
1041         }
1042
1043         psd->revision = orig_psd->revision;
1044         if (security_info_sent & SECINFO_DACL) {
1045                 psd->type = orig_psd->type;
1046                 /* All our SD's are self relative. */
1047                 psd->type |= SEC_DESC_SELF_RELATIVE;
1048         }
1049
1050         if ((security_info_sent & SECINFO_OWNER) && (orig_psd->owner_sid != NULL)) {
1051                 if (!dom_sid_equal(orig_psd->owner_sid, psd->owner_sid)) {
1052                         /* We're changing the owner. */
1053                         chown_needed = true;
1054                 }
1055                 psd->owner_sid = orig_psd->owner_sid;
1056         }
1057         if ((security_info_sent & SECINFO_GROUP) && (orig_psd->group_sid != NULL)) {
1058                 if (!dom_sid_equal(orig_psd->group_sid, psd->group_sid)) {
1059                         /* We're changing the group. */
1060                         chown_needed = true;
1061                 }
1062                 psd->group_sid = orig_psd->group_sid;
1063         }
1064         if (security_info_sent & SECINFO_DACL) {
1065                 if (security_descriptor_with_ms_nfs(orig_psd)) {
1066                         /*
1067                          * If the sd contains a MS NFS SID, do
1068                          * nothing, it's a chmod() request from OS X
1069                          * with AAPL context.
1070                          */
1071                         TALLOC_FREE(frame);
1072                         return NT_STATUS_OK;
1073                 }
1074                 psd->dacl = orig_psd->dacl;
1075                 psd->type |= SEC_DESC_DACL_PRESENT;
1076         }
1077         if (security_info_sent & SECINFO_SACL) {
1078                 psd->sacl = orig_psd->sacl;
1079                 psd->type |= SEC_DESC_SACL_PRESENT;
1080         }
1081
1082         if (ignore_file_system_acl) {
1083                 if (chown_needed) {
1084                         /* send only ownership stuff to lower layer */
1085                         security_info_sent &= (SECINFO_OWNER | SECINFO_GROUP);
1086                         status = set_underlying_acl(handle, fsp, psd,
1087                                                     security_info_sent, true);
1088                         if (!NT_STATUS_IS_OK(status)) {
1089                                 TALLOC_FREE(frame);
1090                                 return status;
1091                         }
1092                 }
1093                 ZERO_ARRAY(hash);
1094                 status = store_v3_blob(store_acl_blob_fsp_fn, handle, fsp, psd,
1095                                        NULL, hash);
1096
1097                 TALLOC_FREE(frame);
1098                 return status;
1099         }
1100
1101         status = set_underlying_acl(handle, fsp, psd, security_info_sent,
1102                                     chown_needed);
1103         if (!NT_STATUS_IS_OK(status)) {
1104                 TALLOC_FREE(frame);
1105                 return status;
1106         }
1107
1108         /* Get the full underlying sd, then hash. */
1109         status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
1110                                           fsp,
1111                                           HASH_SECURITY_INFO,
1112                                           frame,
1113                                           &pdesc_next);
1114
1115         if (!NT_STATUS_IS_OK(status)) {
1116                 TALLOC_FREE(frame);
1117                 return status;
1118         }
1119
1120         status = hash_sd_sha256(pdesc_next, hash);
1121         if (!NT_STATUS_IS_OK(status)) {
1122                 TALLOC_FREE(frame);
1123                 return status;
1124         }
1125
1126         /* Get the full underlying sd, then hash. */
1127         ret = SMB_VFS_NEXT_SYS_ACL_BLOB_GET_FD(handle,
1128                                                fsp,
1129                                                frame,
1130                                                &sys_acl_description,
1131                                                &sys_acl_blob);
1132
1133         /* If we fail to get the ACL blob (for some reason) then this
1134          * is not fatal, we just work based on the NT ACL only */
1135         if (ret != 0) {
1136                 status = store_v3_blob(store_acl_blob_fsp_fn, handle, fsp, psd,
1137                                        pdesc_next, hash);
1138
1139                 TALLOC_FREE(frame);
1140                 return status;
1141         }
1142
1143         status = hash_blob_sha256(sys_acl_blob, sys_acl_hash);
1144         if (!NT_STATUS_IS_OK(status)) {
1145                 TALLOC_FREE(frame);
1146                 return status;
1147         }
1148
1149         if (DEBUGLEVEL >= 10) {
1150                 DBG_DEBUG("storing xattr sd for file %s based on system ACL\n",
1151                           fsp_str_dbg(fsp));
1152                 NDR_PRINT_DEBUG(security_descriptor,
1153                                 discard_const_p(struct security_descriptor, psd));
1154
1155                 DBG_DEBUG("storing hash in xattr sd based on system ACL and:\n");
1156                 NDR_PRINT_DEBUG(security_descriptor,
1157                                 discard_const_p(struct security_descriptor, pdesc_next));
1158         }
1159
1160         /* We store hashes of both the sys ACL blob and the NT
1161          * security desciptor mapped from that ACL so as to improve
1162          * our chances against some inadvertant change breaking the
1163          * hash used */
1164         status = create_sys_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash,
1165                                      sys_acl_description, sys_acl_hash);
1166         if (!NT_STATUS_IS_OK(status)) {
1167                 DBG_DEBUG("create_sys_acl_blob failed\n");
1168                 TALLOC_FREE(frame);
1169                 return status;
1170         }
1171
1172         status = store_acl_blob_fsp_fn(handle, fsp, &blob);
1173
1174         TALLOC_FREE(frame);
1175         return status;
1176 }
1177
1178 static int acl_common_remove_object(vfs_handle_struct *handle,
1179                                         const struct smb_filename *smb_fname,
1180                                         bool is_directory)
1181 {
1182         connection_struct *conn = handle->conn;
1183         struct file_id id;
1184         files_struct *fsp = NULL;
1185         int ret = 0;
1186         struct smb_filename *local_fname = NULL;
1187         struct smb_filename *parent_dir_fname = NULL;
1188         int saved_errno = 0;
1189         struct smb_filename *saved_dir_fname = NULL;
1190         bool ok;
1191
1192         saved_dir_fname = vfs_GetWd(talloc_tos(),conn);
1193         if (saved_dir_fname == NULL) {
1194                 saved_errno = errno;
1195                 goto out;
1196         }
1197
1198         ok = parent_smb_fname(talloc_tos(),
1199                               smb_fname,
1200                               &parent_dir_fname,
1201                               &local_fname);
1202         if (!ok) {
1203                 saved_errno = ENOMEM;
1204                 goto out;
1205         }
1206
1207         DBG_DEBUG("removing %s %s/%s\n", is_directory ? "directory" : "file",
1208                   smb_fname_str_dbg(parent_dir_fname),
1209                   smb_fname_str_dbg(local_fname));
1210
1211         /* cd into the parent dir to pin it. */
1212         ret = vfs_ChDir(conn, parent_dir_fname);
1213         if (ret == -1) {
1214                 saved_errno = errno;
1215                 goto out;
1216         }
1217
1218         /* Must use lstat here. */
1219         ret = SMB_VFS_LSTAT(conn, local_fname);
1220         if (ret == -1) {
1221                 saved_errno = errno;
1222                 goto out;
1223         }
1224
1225         /* Ensure we have this file open with DELETE access. */
1226         id = vfs_file_id_from_sbuf(conn, &local_fname->st);
1227         for (fsp = file_find_di_first(conn->sconn, id); fsp;
1228                      fsp = file_find_di_next(fsp)) {
1229                 if (fsp->access_mask & DELETE_ACCESS &&
1230                     fsp->fsp_flags.delete_on_close)
1231                 {
1232                         /* We did open this for delete,
1233                          * allow the delete as root.
1234                          */
1235                         break;
1236                 }
1237         }
1238
1239         if (!fsp) {
1240                 DBG_DEBUG("%s %s/%s not an open file\n",
1241                           is_directory ? "directory" : "file",
1242                           smb_fname_str_dbg(parent_dir_fname),
1243                           smb_fname_str_dbg(local_fname));
1244                 saved_errno = EACCES;
1245                 goto out;
1246         }
1247
1248         become_root();
1249         if (is_directory) {
1250                 ret = SMB_VFS_NEXT_UNLINKAT(handle,
1251                                 conn->cwd_fsp,
1252                                 local_fname,
1253                                 AT_REMOVEDIR);
1254         } else {
1255                 ret = SMB_VFS_NEXT_UNLINKAT(handle,
1256                                 conn->cwd_fsp,
1257                                 local_fname,
1258                                 0);
1259         }
1260         unbecome_root();
1261
1262         if (ret == -1) {
1263                 saved_errno = errno;
1264         }
1265
1266   out:
1267
1268         TALLOC_FREE(parent_dir_fname);
1269
1270         if (saved_dir_fname) {
1271                 vfs_ChDir(conn, saved_dir_fname);
1272                 TALLOC_FREE(saved_dir_fname);
1273         }
1274         if (saved_errno) {
1275                 errno = saved_errno;
1276         }
1277         return ret;
1278 }
1279
1280 int rmdir_acl_common(struct vfs_handle_struct *handle,
1281                 struct files_struct *dirfsp,
1282                 const struct smb_filename *smb_fname)
1283 {
1284         int ret;
1285
1286         /* Try the normal rmdir first. */
1287         ret = SMB_VFS_NEXT_UNLINKAT(handle,
1288                         dirfsp,
1289                         smb_fname,
1290                         AT_REMOVEDIR);
1291         if (ret == 0) {
1292                 return 0;
1293         }
1294         if (errno == EACCES || errno == EPERM) {
1295                 /* Failed due to access denied,
1296                    see if we need to root override. */
1297                 return acl_common_remove_object(handle,
1298                                                 smb_fname,
1299                                                 true);
1300         }
1301
1302         DBG_DEBUG("unlink of %s failed %s\n",
1303                   smb_fname->base_name,
1304                   strerror(errno));
1305         return -1;
1306 }
1307
1308 int unlink_acl_common(struct vfs_handle_struct *handle,
1309                         struct files_struct *dirfsp,
1310                         const struct smb_filename *smb_fname,
1311                         int flags)
1312 {
1313         int ret;
1314
1315         /* Try the normal unlink first. */
1316         ret = SMB_VFS_NEXT_UNLINKAT(handle,
1317                                 dirfsp,
1318                                 smb_fname,
1319                                 flags);
1320         if (ret == 0) {
1321                 return 0;
1322         }
1323         if (errno == EACCES || errno == EPERM) {
1324                 /* Failed due to access denied,
1325                    see if we need to root override. */
1326
1327                 /* Don't do anything fancy for streams. */
1328                 if (smb_fname->stream_name) {
1329                         return -1;
1330                 }
1331                 return acl_common_remove_object(handle,
1332                                         smb_fname,
1333                                         false);
1334         }
1335
1336         DBG_DEBUG("unlink of %s failed %s\n",
1337                   smb_fname->base_name,
1338                   strerror(errno));
1339         return -1;
1340 }
1341
1342 int chmod_acl_module_common(struct vfs_handle_struct *handle,
1343                             const struct smb_filename *smb_fname,
1344                             mode_t mode)
1345 {
1346         if (smb_fname->flags & SMB_FILENAME_POSIX_PATH) {
1347                 /* Only allow this on POSIX pathnames. */
1348                 return SMB_VFS_NEXT_CHMOD(handle, smb_fname, mode);
1349         }
1350         return 0;
1351 }
1352
1353 int fchmod_acl_module_common(struct vfs_handle_struct *handle,
1354                              struct files_struct *fsp, mode_t mode)
1355 {
1356         if (fsp->posix_flags & FSP_POSIX_FLAGS_OPEN) {
1357                 /* Only allow this on POSIX opens. */
1358                 return SMB_VFS_NEXT_FCHMOD(handle, fsp, mode);
1359         }
1360         return 0;
1361 }