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                                 struct files_struct *fsp,
 414                                 struct files_struct *dirfsp,
 415                                 const struct smb_filename *smb_fname,
 416                                 const DATA_BLOB *blob,
 417                                 struct security_descriptor **ppsd,
 418                                 bool *psd_is_from_fs)
 419 {
 420         NTSTATUS status;
 421         uint16_t hash_type = XATTR_SD_HASH_TYPE_NONE;
 422         uint16_t xattr_version = 0;
 423         uint8_t hash[XATTR_SD_HASH_SIZE];
 424         uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE];
 425         uint8_t hash_tmp[XATTR_SD_HASH_SIZE];
 426         uint8_t sys_acl_hash_tmp[XATTR_SD_HASH_SIZE];
 427         struct security_descriptor *psd = NULL;
 428         struct security_descriptor *psd_blob = NULL;
 429         struct security_descriptor *psd_fs = NULL;
 430         char *sys_acl_blob_description = NULL;
 431         DATA_BLOB sys_acl_blob = { 0 };
 432         struct acl_common_config *config = NULL;
 433
 434         *ppsd = NULL;
 435         *psd_is_from_fs = false;
 436
 437         SMB_VFS_HANDLE_GET_DATA(handle, config,
 438                                 struct acl_common_config,
 439                                 return NT_STATUS_UNSUCCESSFUL);
 440
 441         status = parse_acl_blob(blob,
 442                                 mem_ctx,
 443                                 &psd_blob,
 444                                 &hash_type,
 445                                 &xattr_version,
 446                                 &hash[0],
 447                                 &sys_acl_hash[0]);
 448         if (!NT_STATUS_IS_OK(status)) {
 449                 DBG_DEBUG("parse_acl_blob returned %s\n", nt_errstr(status));
 450                 goto fail;
 451         }
 452
 453         /* determine which type of xattr we got */
 454         switch (xattr_version) {
 455         case 1:
 456         case 2:
 457                 /* These xattr types are unilatteral, they do not
 458                  * require confirmation of the hash.  In particular,
 459                  * the NTVFS file server uses version 1, but
 460                  * 'samba-tool ntacl' can set these as well */
 461                 *ppsd = psd_blob;
 462                 return NT_STATUS_OK;
 463         case 3:
 464         case 4:
 465                 if (config->ignore_system_acls) {
 466                         *ppsd = psd_blob;
 467                         return NT_STATUS_OK;
 468                 }
 469
 470                 break;
 471         default:
 472                 DBG_DEBUG("ACL blob revision mismatch (%u) for file %s\n",
 473                           (unsigned int)hash_type, smb_fname->base_name);
 474                 TALLOC_FREE(psd_blob);
 475                 return NT_STATUS_OK;
 476         }
 477
 478         /* determine which type of xattr we got */
 479         if (hash_type != XATTR_SD_HASH_TYPE_SHA256) {
 480                 DBG_DEBUG("ACL blob hash type (%u) unexpected for file %s\n",
 481                           (unsigned int)hash_type, smb_fname->base_name);
 482                 TALLOC_FREE(psd_blob);
 483                 return NT_STATUS_OK;
 484         }
 485
 486         /* determine which type of xattr we got */
 487         switch (xattr_version) {
 488         case 4:
 489         {
 490                 int ret;
 491                 if (fsp) {
 492                         /* Get the full underlying sd, then hash. */
 493                         ret = SMB_VFS_NEXT_SYS_ACL_BLOB_GET_FD(handle,
 494                                                                fsp,
 495                                                                mem_ctx,
 496                                                                &sys_acl_blob_description,
 497                                                                &sys_acl_blob);
 498                 } else {
 499                         /* Get the full underlying sd, then hash. */
 500                         ret = SMB_VFS_NEXT_SYS_ACL_BLOB_GET_FILE(handle,
 501                                                  smb_fname,
 502                                                  mem_ctx,
 503                                                  &sys_acl_blob_description,
 504                                                  &sys_acl_blob);
 505                 }
 506
 507                 /* If we fail to get the ACL blob (for some reason) then this
 508                  * is not fatal, we just work based on the NT ACL only */
 509                 if (ret == 0) {
 510                         status = hash_blob_sha256(sys_acl_blob, sys_acl_hash_tmp);
 511                         if (!NT_STATUS_IS_OK(status)) {
 512                                 goto fail;
 513                         }
 514
 515                         TALLOC_FREE(sys_acl_blob_description);
 516                         TALLOC_FREE(sys_acl_blob.data);
 517
 518                         if (memcmp(&sys_acl_hash[0], &sys_acl_hash_tmp[0],
 519                                    XATTR_SD_HASH_SIZE) == 0) {
 520                                 /* Hash matches, return blob sd. */
 521                                 DBG_DEBUG("blob hash matches for file %s\n",
 522                                           smb_fname->base_name);
 523                                 *ppsd = psd_blob;
 524                                 return NT_STATUS_OK;
 525                         }
 526                 }
 527
 528                 /* Otherwise, fall though and see if the NT ACL hash matches */
 529                 FALL_THROUGH;
 530         }
 531         case 3:
 532                 /* Get the full underlying sd for the hash
 533                    or to return as backup. */
 534                 if (fsp) {
 535                         status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
 536                                                           fsp,
 537                                                           HASH_SECURITY_INFO,
 538                                                           mem_ctx,
 539                                                           &psd_fs);
 540                 } else {
 541                         status = SMB_VFS_NEXT_GET_NT_ACL_AT(handle,
 542                                                         dirfsp,
 543                                                         smb_fname,
 544                                                         HASH_SECURITY_INFO,
 545                                                         mem_ctx,
 546                                                         &psd_fs);
 547                 }
 548
 549                 if (!NT_STATUS_IS_OK(status)) {
 550                         DBG_DEBUG("get_next_acl for file %s returned %s\n",
 551                                   smb_fname->base_name, nt_errstr(status));
 552                         goto fail;
 553                 }
 554
 555                 status = hash_sd_sha256(psd_fs, hash_tmp);
 556                 if (!NT_STATUS_IS_OK(status)) {
 557                         TALLOC_FREE(psd_blob);
 558                         *ppsd = psd_fs;
 559                         *psd_is_from_fs = true;
 560                         return NT_STATUS_OK;
 561                 }
 562
 563                 if (memcmp(&hash[0], &hash_tmp[0], XATTR_SD_HASH_SIZE) == 0) {
 564                         /* Hash matches, return blob sd. */
 565                         DBG_DEBUG("blob hash matches for file %s\n",
 566                                   smb_fname->base_name);
 567                         *ppsd = psd_blob;
 568                         return NT_STATUS_OK;
 569                 }
 570
 571                 /* Hash doesn't match, return underlying sd. */
 572                 DBG_DEBUG("blob hash does not match for file %s - returning "
 573                           "file system SD mapping.\n",
 574                           smb_fname->base_name);
 575
 576                 if (DEBUGLEVEL >= 10) {
 577                         DBG_DEBUG("acl for blob hash for %s is:\n",
 578                                   smb_fname->base_name);
 579                         NDR_PRINT_DEBUG(security_descriptor, psd_fs);
 580                 }
 581
 582                 TALLOC_FREE(psd_blob);
 583                 *ppsd = psd_fs;
 584                 *psd_is_from_fs = true;
 585         }
 586
 587         return NT_STATUS_OK;
 588
 589 fail:
 590         TALLOC_FREE(psd);
 591         TALLOC_FREE(psd_blob);
 592         TALLOC_FREE(psd_fs);
 593         TALLOC_FREE(sys_acl_blob_description);
 594         TALLOC_FREE(sys_acl_blob.data);
 595         return status;
 596 }
 597
 598 /*******************************************************************
 599  Pull a DATA_BLOB from an xattr given an fsp.
 600  If the hash doesn't match, or doesn't exist - return the underlying
 601  filesystem sd.
 602 *******************************************************************/
 603
 604 NTSTATUS fget_nt_acl_common(
 605         NTSTATUS (*fget_acl_blob_fn)(TALLOC_CTX *ctx,
 606                                     vfs_handle_struct *handle,
 607                                     files_struct *fsp,
 608                                     DATA_BLOB *pblob),
 609         vfs_handle_struct *handle,
 610         files_struct *fsp,
 611         uint32_t security_info,
 612         TALLOC_CTX *mem_ctx,
 613         struct security_descriptor **ppdesc)
 614 {
 615         DATA_BLOB blob = data_blob_null;
 616         NTSTATUS status;
 617         struct security_descriptor *psd = NULL;
 618         const struct smb_filename *smb_fname = fsp->fsp_name;
 619         bool psd_is_from_fs = false;
 620         struct acl_common_config *config = NULL;
 621
 622         SMB_VFS_HANDLE_GET_DATA(handle, config,
 623                                 struct acl_common_config,
 624                                 return NT_STATUS_UNSUCCESSFUL);
 625
 626         DBG_DEBUG("name=%s\n", smb_fname->base_name);
 627
 628         status = fget_acl_blob_fn(mem_ctx, handle, fsp, &blob);
 629         if (NT_STATUS_IS_OK(status)) {
 630                 status = validate_nt_acl_blob(mem_ctx,
 631                                         handle,
 632                                         fsp,
 633                                         NULL,
 634                                         smb_fname,
 635                                         &blob,
 636                                         &psd,
 637                                         &psd_is_from_fs);
 638                 TALLOC_FREE(blob.data);
 639                 if (!NT_STATUS_IS_OK(status)) {
 640                         DBG_DEBUG("ACL validation for [%s] failed\n",
 641                                   smb_fname->base_name);
 642                         goto fail;
 643                 }
 644         }
 645
 646         if (psd == NULL) {
 647                 /* Get the full underlying sd, as we failed to get the
 648                  * blob for the hash, or the revision/hash type wasn't
 649                  * known */
 650
 651                 if (config->ignore_system_acls) {
 652                         status = vfs_stat_fsp(fsp);
 653                         if (!NT_STATUS_IS_OK(status)) {
 654                                 goto fail;
 655                         }
 656
 657                         status = make_default_filesystem_acl(
 658                                 mem_ctx,
 659                                 config->default_acl_style,
 660                                 smb_fname->base_name,
 661                                 &fsp->fsp_name->st,
 662                                 &psd);
 663                         if (!NT_STATUS_IS_OK(status)) {
 664                                 goto fail;
 665                         }
 666                 } else {
 667                         status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
 668                                                           fsp,
 669                                                           security_info,
 670                                                           mem_ctx,
 671                                                           &psd);
 672
 673                         if (!NT_STATUS_IS_OK(status)) {
 674                                 DBG_DEBUG("get_next_acl for file %s "
 675                                           "returned %s\n",
 676                                           smb_fname->base_name,
 677                                           nt_errstr(status));
 678                                 goto fail;
 679                         }
 680
 681                         psd_is_from_fs = true;
 682                 }
 683         }
 684
 685         if (psd_is_from_fs) {
 686                 status = vfs_stat_fsp(fsp);
 687                 if (!NT_STATUS_IS_OK(status)) {
 688                         goto fail;
 689                 }
 690
 691                 /*
 692                  * We're returning the underlying ACL from the
 693                  * filesystem. If it's a directory, and has no
 694                  * inheritable ACE entries we have to fake them.
 695                  */
 696
 697                 if (fsp->fsp_flags.is_directory &&
 698                                 !sd_has_inheritable_components(psd, true)) {
 699                         status = add_directory_inheritable_components(
 700                                 handle,
 701                                 smb_fname->base_name,
 702                                 &fsp->fsp_name->st,
 703                                 psd);
 704                         if (!NT_STATUS_IS_OK(status)) {
 705                                 goto fail;
 706                         }
 707                 }
 708
 709                 /*
 710                  * The underlying POSIX module always sets the
 711                  * ~SEC_DESC_DACL_PROTECTED bit, as ACLs can't be inherited in
 712                  * this way under POSIX. Remove it for Windows-style ACLs.
 713                  */
 714                 psd->type &= ~SEC_DESC_DACL_PROTECTED;
 715         }
 716
 717         if (!(security_info & SECINFO_OWNER)) {
 718                 psd->owner_sid = NULL;
 719         }
 720         if (!(security_info & SECINFO_GROUP)) {
 721                 psd->group_sid = NULL;
 722         }
 723         if (!(security_info & SECINFO_DACL)) {
 724                 psd->type &= ~SEC_DESC_DACL_PRESENT;
 725                 psd->dacl = NULL;
 726         }
 727         if (!(security_info & SECINFO_SACL)) {
 728                 psd->type &= ~SEC_DESC_SACL_PRESENT;
 729                 psd->sacl = NULL;
 730         }
 731
 732         if (DEBUGLEVEL >= 10) {
 733                 DBG_DEBUG("returning acl for %s is:\n",
 734                           smb_fname->base_name);
 735                 NDR_PRINT_DEBUG(security_descriptor, psd);
 736         }
 737
 738         *ppdesc = psd;
 739
 740         return NT_STATUS_OK;
 741
 742 fail:
 743         TALLOC_FREE(psd);
 744         return status;
 745 }
 746
 747 /*******************************************************************
 748  Pull a DATA_BLOB from an xattr given a pathname.
 749  If the hash doesn't match, or doesn't exist - return the underlying
 750  filesystem sd.
 751 *******************************************************************/
 752
 753 NTSTATUS get_nt_acl_common_at(
 754         NTSTATUS (*get_acl_blob_at_fn)(TALLOC_CTX *ctx,
 755                                     vfs_handle_struct *handle,
 756                                     struct files_struct *dirfsp,
 757                                     const struct smb_filename *smb_fname,
 758                                     DATA_BLOB *pblob),
 759         vfs_handle_struct *handle,
 760         struct files_struct *dirfsp,
 761         const struct smb_filename *smb_fname_in,
 762         uint32_t security_info,
 763         TALLOC_CTX *mem_ctx,
 764         struct security_descriptor **ppdesc)
 765 {
 766         DATA_BLOB blob = data_blob_null;
 767         NTSTATUS status;
 768         struct security_descriptor *psd = NULL;
 769         bool psd_is_from_fs = false;
 770         struct acl_common_config *config = NULL;
 771
 772         SMB_VFS_HANDLE_GET_DATA(handle, config,
 773                                 struct acl_common_config,
 774                                 return NT_STATUS_UNSUCCESSFUL);
 775
 776         DBG_DEBUG("name=%s\n", smb_fname_in->base_name);
 777
 778         status = get_acl_blob_at_fn(mem_ctx,
 779                                 handle,
 780                                 dirfsp,
 781                                 smb_fname_in,
 782                                 &blob);
 783         if (NT_STATUS_IS_OK(status)) {
 784                 status = validate_nt_acl_blob(mem_ctx,
 785                                         handle,
 786                                         NULL,
 787                                         dirfsp,
 788                                         smb_fname_in,
 789                                         &blob,
 790                                         &psd,
 791                                         &psd_is_from_fs);
 792                 TALLOC_FREE(blob.data);
 793                 if (!NT_STATUS_IS_OK(status)) {
 794                         DBG_DEBUG("ACL validation for [%s] failed\n",
 795                                   smb_fname_in->base_name);
 796                         goto fail;
 797                 }
 798         }
 799
 800         if (psd == NULL) {
 801                 /* Get the full underlying sd, as we failed to get the
 802                  * blob for the hash, or the revision/hash type wasn't
 803                  * known */
 804
 805                 if (config->ignore_system_acls) {
 806                         SMB_STRUCT_STAT sbuf;
 807                         int ret;
 808
 809                         ret = vfs_stat_smb_basename(handle->conn,
 810                                         smb_fname_in,
 811                                         &sbuf);
 812                         if (ret == -1) {
 813                                 status = map_nt_error_from_unix(errno);
 814                                 goto fail;
 815                         }
 816
 817                         status = make_default_filesystem_acl(
 818                                 mem_ctx,
 819                                 config->default_acl_style,
 820                                 smb_fname_in->base_name,
 821                                 &sbuf,
 822                                 &psd);
 823                         if (!NT_STATUS_IS_OK(status)) {
 824                                 goto fail;
 825                         }
 826                 } else {
 827                         status = SMB_VFS_NEXT_GET_NT_ACL_AT(handle,
 828                                                 dirfsp,
 829                                                 smb_fname_in,
 830                                                 security_info,
 831                                                 mem_ctx,
 832                                                 &psd);
 833
 834                         if (!NT_STATUS_IS_OK(status)) {
 835                                 DBG_DEBUG("get_next_acl for file %s "
 836                                           "returned %s\n",
 837                                           smb_fname_in->base_name,
 838                                           nt_errstr(status));
 839                                 goto fail;
 840                         }
 841
 842                         psd_is_from_fs = true;
 843                 }
 844         }
 845
 846         if (psd_is_from_fs) {
 847                 SMB_STRUCT_STAT sbuf;
 848                 bool is_directory = false;
 849                 int ret;
 850
 851                 /*
 852                  * We're returning the underlying ACL from the
 853                  * filesystem. If it's a directory, and has no
 854                  * inheritable ACE entries we have to fake them.
 855                  */
 856
 857                 ret = vfs_stat_smb_basename(handle->conn,
 858                                 smb_fname_in,
 859                                 &sbuf);
 860                 if (ret == -1) {
 861                         status = map_nt_error_from_unix(errno);
 862                         goto fail;
 863                 }
 864
 865                 is_directory = S_ISDIR(sbuf.st_ex_mode);
 866
 867                 if (is_directory && !sd_has_inheritable_components(psd, true)) {
 868                         status = add_directory_inheritable_components(
 869                                 handle,
 870                                 smb_fname_in->base_name,
 871                                 &sbuf,
 872                                 psd);
 873                         if (!NT_STATUS_IS_OK(status)) {
 874                                 goto fail;
 875                         }
 876                 }
 877
 878                 /*
 879                  * The underlying POSIX module always sets the
 880                  * ~SEC_DESC_DACL_PROTECTED bit, as ACLs can't be inherited in
 881                  * this way under POSIX. Remove it for Windows-style ACLs.
 882                  */
 883                 psd->type &= ~SEC_DESC_DACL_PROTECTED;
 884         }
 885
 886         if (!(security_info & SECINFO_OWNER)) {
 887                 psd->owner_sid = NULL;
 888         }
 889         if (!(security_info & SECINFO_GROUP)) {
 890                 psd->group_sid = NULL;
 891         }
 892         if (!(security_info & SECINFO_DACL)) {
 893                 psd->type &= ~SEC_DESC_DACL_PRESENT;
 894                 psd->dacl = NULL;
 895         }
 896         if (!(security_info & SECINFO_SACL)) {
 897                 psd->type &= ~SEC_DESC_SACL_PRESENT;
 898                 psd->sacl = NULL;
 899         }
 900
 901         if (DEBUGLEVEL >= 10) {
 902                 DBG_DEBUG("returning acl for %s is:\n",
 903                           smb_fname_in->base_name);
 904                 NDR_PRINT_DEBUG(security_descriptor, psd);
 905         }
 906
 907         *ppdesc = psd;
 908
 909         return NT_STATUS_OK;
 910
 911 fail:
 912         TALLOC_FREE(psd);
 913         return status;
 914 }
 915
 916 /*********************************************************************
 917  Set the underlying ACL (e.g. POSIX ACLS, POSIX owner, etc)
 918 *********************************************************************/
 919 static NTSTATUS set_underlying_acl(vfs_handle_struct *handle, files_struct *fsp,
 920                                    struct security_descriptor *psd,
 921                                    uint32_t security_info_sent,
 922                                    bool chown_needed)
 923 {
 924         NTSTATUS status;
 925         const struct security_token *token = NULL;
 926         struct dom_sid_buf buf;
 927
 928         status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
 929         if (!NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED)) {
 930                 return status;
 931         }
 932
 933         /* We got access denied here. If we're already root,
 934            or we didn't need to do a chown, or the fsp isn't
 935            open with WRITE_OWNER access, just return. */
 936         if (get_current_uid(handle->conn) == 0 || chown_needed == false ||
 937             !(fsp->access_mask & SEC_STD_WRITE_OWNER)) {
 938                 return NT_STATUS_ACCESS_DENIED;
 939         }
 940
 941         /*
 942          * Only allow take-ownership, not give-ownership. That's the way Windows
 943          * implements SEC_STD_WRITE_OWNER. MS-FSA 2.1.5.16 just states: If
 944          * InputBuffer.OwnerSid is not a valid owner SID for a file in the
 945          * objectstore, as determined in an implementation specific manner, the
 946          * object store MUST return STATUS_INVALID_OWNER.
 947          */
 948         token = get_current_nttok(fsp->conn);
 949         if (!security_token_is_sid(token, psd->owner_sid)) {
 950                 return NT_STATUS_INVALID_OWNER;
 951         }
 952
 953         DBG_DEBUG("overriding chown on file %s for sid %s\n",
 954                   fsp_str_dbg(fsp),
 955                   dom_sid_str_buf(psd->owner_sid, &buf));
 956
 957         /* Ok, we failed to chown and we have
 958            SEC_STD_WRITE_OWNER access - override. */
 959         become_root();
 960         status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
 961         unbecome_root();
 962
 963         return status;
 964 }
 965
 966 /*********************************************************************
 967  Store a v3 security descriptor
 968 *********************************************************************/
 969 static NTSTATUS store_v3_blob(
 970         NTSTATUS (*store_acl_blob_fsp_fn)(vfs_handle_struct *handle,
 971                                           files_struct *fsp,
 972                                           DATA_BLOB *pblob),
 973         vfs_handle_struct *handle, files_struct *fsp,
 974         struct security_descriptor *psd,
 975         struct security_descriptor *pdesc_next,
 976         uint8_t hash[XATTR_SD_HASH_SIZE])
 977 {
 978         NTSTATUS status;
 979         DATA_BLOB blob;
 980
 981         if (DEBUGLEVEL >= 10) {
 982                 DBG_DEBUG("storing xattr sd for file %s\n",
 983                           fsp_str_dbg(fsp));
 984                 NDR_PRINT_DEBUG(
 985                     security_descriptor,
 986                     discard_const_p(struct security_descriptor, psd));
 987
 988                 if (pdesc_next != NULL) {
 989                         DBG_DEBUG("storing xattr sd based on \n");
 990                         NDR_PRINT_DEBUG(
 991                             security_descriptor,
 992                             discard_const_p(struct security_descriptor,
 993                                             pdesc_next));
 994                 } else {
 995                         DBG_DEBUG("ignoring underlying sd\n");
 996                 }
 997         }
 998         status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
 999         if (!NT_STATUS_IS_OK(status)) {
1000                 DBG_DEBUG("create_acl_blob failed\n");
1001                 return status;
1002         }
1003
1004         status = store_acl_blob_fsp_fn(handle, fsp, &blob);
1005         return status;
1006 }
1007
1008 /*********************************************************************
1009  Store a security descriptor given an fsp.
1010 *********************************************************************/
1011
1012 NTSTATUS fset_nt_acl_common(
1013         NTSTATUS (*fget_acl_blob_fn)(TALLOC_CTX *ctx,
1014                                     vfs_handle_struct *handle,
1015                                     files_struct *fsp,
1016                                     DATA_BLOB *pblob),
1017         NTSTATUS (*store_acl_blob_fsp_fn)(vfs_handle_struct *handle,
1018                                           files_struct *fsp,
1019                                           DATA_BLOB *pblob),
1020         const char *module_name,
1021         vfs_handle_struct *handle, files_struct *fsp,
1022         uint32_t security_info_sent,
1023         const struct security_descriptor *orig_psd)
1024 {
1025         NTSTATUS status;
1026         int ret;
1027         DATA_BLOB blob, sys_acl_blob;
1028         struct security_descriptor *pdesc_next = NULL;
1029         struct security_descriptor *psd = NULL;
1030         uint8_t hash[XATTR_SD_HASH_SIZE];
1031         uint8_t sys_acl_hash[XATTR_SD_HASH_SIZE];
1032         bool chown_needed = false;
1033         char *sys_acl_description;
1034         TALLOC_CTX *frame = talloc_stackframe();
1035         bool ignore_file_system_acl = lp_parm_bool(
1036             SNUM(handle->conn), module_name, "ignore system acls", false);
1037
1038         if (DEBUGLEVEL >= 10) {
1039                 DBG_DEBUG("incoming sd for file %s\n", fsp_str_dbg(fsp));
1040                 NDR_PRINT_DEBUG(security_descriptor,
1041                         discard_const_p(struct security_descriptor, orig_psd));
1042         }
1043
1044         status = fget_nt_acl_common(fget_acl_blob_fn, handle, fsp,
1045                         SECINFO_OWNER|SECINFO_GROUP|SECINFO_DACL|SECINFO_SACL,
1046                                      frame,
1047                         &psd);
1048
1049         if (!NT_STATUS_IS_OK(status)) {
1050                 TALLOC_FREE(frame);
1051                 return status;
1052         }
1053
1054         psd->revision = orig_psd->revision;
1055         if (security_info_sent & SECINFO_DACL) {
1056                 psd->type = orig_psd->type;
1057                 /* All our SD's are self relative. */
1058                 psd->type |= SEC_DESC_SELF_RELATIVE;
1059         }
1060
1061         if ((security_info_sent & SECINFO_OWNER) && (orig_psd->owner_sid != NULL)) {
1062                 if (!dom_sid_equal(orig_psd->owner_sid, psd->owner_sid)) {
1063                         /* We're changing the owner. */
1064                         chown_needed = true;
1065                 }
1066                 psd->owner_sid = orig_psd->owner_sid;
1067         }
1068         if ((security_info_sent & SECINFO_GROUP) && (orig_psd->group_sid != NULL)) {
1069                 if (!dom_sid_equal(orig_psd->group_sid, psd->group_sid)) {
1070                         /* We're changing the group. */
1071                         chown_needed = true;
1072                 }
1073                 psd->group_sid = orig_psd->group_sid;
1074         }
1075         if (security_info_sent & SECINFO_DACL) {
1076                 if (security_descriptor_with_ms_nfs(orig_psd)) {
1077                         /*
1078                          * If the sd contains a MS NFS SID, do
1079                          * nothing, it's a chmod() request from OS X
1080                          * with AAPL context.
1081                          */
1082                         TALLOC_FREE(frame);
1083                         return NT_STATUS_OK;
1084                 }
1085                 psd->dacl = orig_psd->dacl;
1086                 psd->type |= SEC_DESC_DACL_PRESENT;
1087         }
1088         if (security_info_sent & SECINFO_SACL) {
1089                 psd->sacl = orig_psd->sacl;
1090                 psd->type |= SEC_DESC_SACL_PRESENT;
1091         }
1092
1093         if (ignore_file_system_acl) {
1094                 if (chown_needed) {
1095                         /* send only ownership stuff to lower layer */
1096                         security_info_sent &= (SECINFO_OWNER | SECINFO_GROUP);
1097                         status = set_underlying_acl(handle, fsp, psd,
1098                                                     security_info_sent, true);
1099                         if (!NT_STATUS_IS_OK(status)) {
1100                                 goto done;
1101                         }
1102                 }
1103                 ZERO_ARRAY(hash);
1104                 status = store_v3_blob(store_acl_blob_fsp_fn, handle, fsp, psd,
1105                                        NULL, hash);
1106                 goto done;
1107         }
1108
1109         status = set_underlying_acl(handle, fsp, psd, security_info_sent,
1110                                     chown_needed);
1111         if (!NT_STATUS_IS_OK(status)) {
1112                 goto done;
1113         }
1114
1115         /* Get the full underlying sd, then hash. */
1116         status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
1117                                           fsp,
1118                                           HASH_SECURITY_INFO,
1119                                           frame,
1120                                           &pdesc_next);
1121
1122         if (!NT_STATUS_IS_OK(status)) {
1123                 goto done;
1124         }
1125
1126         status = hash_sd_sha256(pdesc_next, hash);
1127         if (!NT_STATUS_IS_OK(status)) {
1128                 goto done;
1129         }
1130
1131         /* Get the full underlying sd, then hash. */
1132         ret = SMB_VFS_NEXT_SYS_ACL_BLOB_GET_FD(handle,
1133                                                fsp,
1134                                                frame,
1135                                                &sys_acl_description,
1136                                                &sys_acl_blob);
1137
1138         /* If we fail to get the ACL blob (for some reason) then this
1139          * is not fatal, we just work based on the NT ACL only */
1140         if (ret != 0) {
1141                 status = store_v3_blob(store_acl_blob_fsp_fn, handle, fsp, psd,
1142                                        pdesc_next, hash);
1143
1144                 goto done;
1145         }
1146
1147         status = hash_blob_sha256(sys_acl_blob, sys_acl_hash);
1148         if (!NT_STATUS_IS_OK(status)) {
1149                 goto done;
1150         }
1151
1152         if (DEBUGLEVEL >= 10) {
1153                 DBG_DEBUG("storing xattr sd for file %s based on system ACL\n",
1154                           fsp_str_dbg(fsp));
1155                 NDR_PRINT_DEBUG(security_descriptor,
1156                                 discard_const_p(struct security_descriptor, psd));
1157
1158                 DBG_DEBUG("storing hash in xattr sd based on system ACL and:\n");
1159                 NDR_PRINT_DEBUG(security_descriptor,
1160                                 discard_const_p(struct security_descriptor, pdesc_next));
1161         }
1162
1163         /* We store hashes of both the sys ACL blob and the NT
1164          * security desciptor mapped from that ACL so as to improve
1165          * our chances against some inadvertant change breaking the
1166          * hash used */
1167         status = create_sys_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash,
1168                                      sys_acl_description, sys_acl_hash);
1169         if (!NT_STATUS_IS_OK(status)) {
1170                 DBG_DEBUG("create_sys_acl_blob failed\n");
1171                 goto done;
1172         }
1173
1174         status = store_acl_blob_fsp_fn(handle, fsp, &blob);
1175
1176 done:
1177         TALLOC_FREE(frame);
1178         return status;
1179 }
1180
1181 static int acl_common_remove_object(vfs_handle_struct *handle,
1182                                         const struct smb_filename *smb_fname,
1183                                         bool is_directory)
1184 {
1185         connection_struct *conn = handle->conn;
1186         struct file_id id;
1187         files_struct *fsp = NULL;
1188         int ret = 0;
1189         struct smb_filename *local_fname = NULL;
1190         struct smb_filename *parent_dir_fname = NULL;
1191         int saved_errno = 0;
1192         struct smb_filename *saved_dir_fname = NULL;
1193         bool ok;
1194
1195         saved_dir_fname = vfs_GetWd(talloc_tos(),conn);
1196         if (saved_dir_fname == NULL) {
1197                 saved_errno = errno;
1198                 goto out;
1199         }
1200
1201         ok = parent_smb_fname(talloc_tos(),
1202                               smb_fname,
1203                               &parent_dir_fname,
1204                               &local_fname);
1205         if (!ok) {
1206                 saved_errno = ENOMEM;
1207                 goto out;
1208         }
1209
1210         DBG_DEBUG("removing %s %s/%s\n", is_directory ? "directory" : "file",
1211                   smb_fname_str_dbg(parent_dir_fname),
1212                   smb_fname_str_dbg(local_fname));
1213
1214         /* cd into the parent dir to pin it. */
1215         ret = vfs_ChDir(conn, parent_dir_fname);
1216         if (ret == -1) {
1217                 saved_errno = errno;
1218                 goto out;
1219         }
1220
1221         /* Must use lstat here. */
1222         ret = SMB_VFS_LSTAT(conn, local_fname);
1223         if (ret == -1) {
1224                 saved_errno = errno;
1225                 goto out;
1226         }
1227
1228         /* Ensure we have this file open with DELETE access. */
1229         id = vfs_file_id_from_sbuf(conn, &local_fname->st);
1230         for (fsp = file_find_di_first(conn->sconn, id, true); fsp;
1231                      fsp = file_find_di_next(fsp, true)) {
1232                 if (fsp->access_mask & DELETE_ACCESS &&
1233                     fsp->fsp_flags.delete_on_close)
1234                 {
1235                         /* We did open this for delete,
1236                          * allow the delete as root.
1237                          */
1238                         break;
1239                 }
1240         }
1241
1242         if (!fsp) {
1243                 DBG_DEBUG("%s %s/%s not an open file\n",
1244                           is_directory ? "directory" : "file",
1245                           smb_fname_str_dbg(parent_dir_fname),
1246                           smb_fname_str_dbg(local_fname));
1247                 saved_errno = EACCES;
1248                 goto out;
1249         }
1250
1251         become_root();
1252         if (is_directory) {
1253                 ret = SMB_VFS_NEXT_UNLINKAT(handle,
1254                                 conn->cwd_fsp,
1255                                 local_fname,
1256                                 AT_REMOVEDIR);
1257         } else {
1258                 ret = SMB_VFS_NEXT_UNLINKAT(handle,
1259                                 conn->cwd_fsp,
1260                                 local_fname,
1261                                 0);
1262         }
1263         unbecome_root();
1264
1265         if (ret == -1) {
1266                 saved_errno = errno;
1267         }
1268
1269   out:
1270
1271         TALLOC_FREE(parent_dir_fname);
1272
1273         if (saved_dir_fname) {
1274                 vfs_ChDir(conn, saved_dir_fname);
1275                 TALLOC_FREE(saved_dir_fname);
1276         }
1277         if (saved_errno) {
1278                 errno = saved_errno;
1279         }
1280         return ret;
1281 }
1282
1283 int rmdir_acl_common(struct vfs_handle_struct *handle,
1284                 struct files_struct *dirfsp,
1285                 const struct smb_filename *smb_fname)
1286 {
1287         int ret;
1288
1289         /* Try the normal rmdir first. */
1290         ret = SMB_VFS_NEXT_UNLINKAT(handle,
1291                         dirfsp,
1292                         smb_fname,
1293                         AT_REMOVEDIR);
1294         if (ret == 0) {
1295                 return 0;
1296         }
1297         if (errno == EACCES || errno == EPERM) {
1298                 /* Failed due to access denied,
1299                    see if we need to root override. */
1300                 return acl_common_remove_object(handle,
1301                                                 smb_fname,
1302                                                 true);
1303         }
1304
1305         DBG_DEBUG("unlink of %s failed %s\n",
1306                   smb_fname->base_name,
1307                   strerror(errno));
1308         return -1;
1309 }
1310
1311 int unlink_acl_common(struct vfs_handle_struct *handle,
1312                         struct files_struct *dirfsp,
1313                         const struct smb_filename *smb_fname,
1314                         int flags)
1315 {
1316         int ret;
1317
1318         /* Try the normal unlink first. */
1319         ret = SMB_VFS_NEXT_UNLINKAT(handle,
1320                                 dirfsp,
1321                                 smb_fname,
1322                                 flags);
1323         if (ret == 0) {
1324                 return 0;
1325         }
1326         if (errno == EACCES || errno == EPERM) {
1327                 /* Failed due to access denied,
1328                    see if we need to root override. */
1329
1330                 /* Don't do anything fancy for streams. */
1331                 if (smb_fname->stream_name) {
1332                         return -1;
1333                 }
1334                 return acl_common_remove_object(handle,
1335                                         smb_fname,
1336                                         false);
1337         }
1338
1339         DBG_DEBUG("unlink of %s failed %s\n",
1340                   smb_fname->base_name,
1341                   strerror(errno));
1342         return -1;
1343 }
1344
1345 int chmod_acl_module_common(struct vfs_handle_struct *handle,
1346                             const struct smb_filename *smb_fname,
1347                             mode_t mode)
1348 {
1349         if (smb_fname->flags & SMB_FILENAME_POSIX_PATH) {
1350                 /* Only allow this on POSIX pathnames. */
1351                 return SMB_VFS_NEXT_CHMOD(handle, smb_fname, mode);
1352         }
1353         return 0;
1354 }
1355
1356 int fchmod_acl_module_common(struct vfs_handle_struct *handle,
1357                              struct files_struct *fsp, mode_t mode)
1358 {
1359         if (fsp->posix_flags & FSP_POSIX_FLAGS_OPEN) {
1360                 /* Only allow this on POSIX opens. */
1361                 return SMB_VFS_NEXT_FCHMOD(handle, fsp, mode);
1362         }
1363         return 0;
1364 }