source3/modules/vfs_acl_tdb.c

   1 /*
   2  * Store Windows ACLs in a tdb.
   3  *
   4  * Copyright (C) Volker Lendecke, 2008
   5  * Copyright (C) Jeremy Allison, 2008
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "includes.h"
  22 #include "smbd/smbd.h"
  23 #include "system/filesys.h"
  24 #include "librpc/gen_ndr/xattr.h"
  25 #include "../lib/crypto/sha256.h"
  26 #include "dbwrap/dbwrap.h"
  27 #include "dbwrap/dbwrap_open.h"
  28 #include "auth.h"
  29 #include "util_tdb.h"
  30 #include "vfs_acl_common.h"
  31
  32 #undef DBGC_CLASS
  33 #define DBGC_CLASS DBGC_VFS
  34
  35 #define ACL_MODULE_NAME "acl_tdb"
  36
  37 static unsigned int ref_count;
  38 static struct db_context *acl_db;
  39
  40 /*******************************************************************
  41  Open acl_db if not already open, increment ref count.
  42 *******************************************************************/
  43
  44 static bool acl_tdb_init(void)
  45 {
  46         char *dbname;
  47
  48         if (acl_db) {
  49                 ref_count++;
  50                 return true;
  51         }
  52
  53         dbname = state_path("file_ntacls.tdb");
  54
  55         if (dbname == NULL) {
  56                 errno = ENOSYS;
  57                 return false;
  58         }
  59
  60         become_root();
  61         acl_db = db_open(NULL, dbname, 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600,
  62                          DBWRAP_LOCK_ORDER_1, DBWRAP_FLAG_NONE);
  63         unbecome_root();
  64
  65         if (acl_db == NULL) {
  66 #if defined(ENOTSUP)
  67                 errno = ENOTSUP;
  68 #else
  69                 errno = ENOSYS;
  70 #endif
  71                 TALLOC_FREE(dbname);
  72                 return false;
  73         }
  74
  75         ref_count++;
  76         TALLOC_FREE(dbname);
  77         return true;
  78 }
  79
  80 /*******************************************************************
  81  Lower ref count and close acl_db if zero.
  82 *******************************************************************/
  83
  84 static void disconnect_acl_tdb(struct vfs_handle_struct *handle)
  85 {
  86         SMB_VFS_NEXT_DISCONNECT(handle);
  87         ref_count--;
  88         if (ref_count == 0) {
  89                 TALLOC_FREE(acl_db);
  90         }
  91 }
  92
  93 /*******************************************************************
  94  Fetch_lock the tdb acl record for a file
  95 *******************************************************************/
  96
  97 static struct db_record *acl_tdb_lock(TALLOC_CTX *mem_ctx,
  98                                         struct db_context *db,
  99                                         const struct file_id *id)
 100 {
 101         uint8_t id_buf[16];
 102
 103         /* For backwards compatibility only store the dev/inode. */
 104         push_file_id_16((char *)id_buf, id);
 105         return dbwrap_fetch_locked(db,
 106                                    mem_ctx,
 107                                    make_tdb_data(id_buf,
 108                                                  sizeof(id_buf)));
 109 }
 110
 111 /*******************************************************************
 112  Delete the tdb acl record for a file
 113 *******************************************************************/
 114
 115 static NTSTATUS acl_tdb_delete(vfs_handle_struct *handle,
 116                                 struct db_context *db,
 117                                 SMB_STRUCT_STAT *psbuf)
 118 {
 119         NTSTATUS status;
 120         struct file_id id = vfs_file_id_from_sbuf(handle->conn, psbuf);
 121         struct db_record *rec = acl_tdb_lock(talloc_tos(), db, &id);
 122
 123         /*
 124          * If rec == NULL there's not much we can do about it
 125          */
 126
 127         if (rec == NULL) {
 128                 DEBUG(10,("acl_tdb_delete: rec == NULL\n"));
 129                 TALLOC_FREE(rec);
 130                 return NT_STATUS_OK;
 131         }
 132
 133         status = dbwrap_record_delete(rec);
 134         TALLOC_FREE(rec);
 135         return status;
 136 }
 137
 138 /*******************************************************************
 139  Pull a security descriptor into a DATA_BLOB from a tdb store.
 140 *******************************************************************/
 141
 142 static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
 143                         vfs_handle_struct *handle,
 144                         files_struct *fsp,
 145                         const struct smb_filename *smb_fname,
 146                         DATA_BLOB *pblob)
 147 {
 148         uint8_t id_buf[16];
 149         TDB_DATA data;
 150         struct file_id id;
 151         struct db_context *db = acl_db;
 152         NTSTATUS status = NT_STATUS_OK;
 153         SMB_STRUCT_STAT sbuf;
 154
 155         ZERO_STRUCT(sbuf);
 156
 157         if (fsp) {
 158                 status = vfs_stat_fsp(fsp);
 159                 sbuf = fsp->fsp_name->st;
 160         } else {
 161                 int ret = vfs_stat_smb_basename(handle->conn,
 162                                 smb_fname,
 163                                 &sbuf);
 164                 if (ret == -1) {
 165                         status = map_nt_error_from_unix(errno);
 166                 }
 167         }
 168
 169         if (!NT_STATUS_IS_OK(status)) {
 170                 return status;
 171         }
 172
 173         id = vfs_file_id_from_sbuf(handle->conn, &sbuf);
 174
 175         /* For backwards compatibility only store the dev/inode. */
 176         push_file_id_16((char *)id_buf, &id);
 177
 178         status = dbwrap_fetch(db,
 179                               ctx,
 180                               make_tdb_data(id_buf, sizeof(id_buf)),
 181                               &data);
 182         if (!NT_STATUS_IS_OK(status)) {
 183                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 184         }
 185
 186         pblob->data = data.dptr;
 187         pblob->length = data.dsize;
 188
 189         DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
 190                 (unsigned int)data.dsize, smb_fname->base_name ));
 191
 192         if (pblob->length == 0 || pblob->data == NULL) {
 193                 return NT_STATUS_NOT_FOUND;
 194         }
 195         return NT_STATUS_OK;
 196 }
 197
 198 /*******************************************************************
 199  Store a DATA_BLOB into a tdb record given an fsp pointer.
 200 *******************************************************************/
 201
 202 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
 203                                 files_struct *fsp,
 204                                 DATA_BLOB *pblob)
 205 {
 206         uint8_t id_buf[16];
 207         struct file_id id;
 208         TDB_DATA data;
 209         struct db_context *db = acl_db;
 210         struct db_record *rec;
 211         NTSTATUS status;
 212
 213         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
 214                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
 215
 216         status = vfs_stat_fsp(fsp);
 217         if (!NT_STATUS_IS_OK(status)) {
 218                 return status;
 219         }
 220
 221         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 222
 223         /* For backwards compatibility only store the dev/inode. */
 224         push_file_id_16((char *)id_buf, &id);
 225         rec = dbwrap_fetch_locked(db, talloc_tos(),
 226                                   make_tdb_data(id_buf,
 227                                                 sizeof(id_buf)));
 228         if (rec == NULL) {
 229                 DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
 230                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 231         }
 232         data.dptr = pblob->data;
 233         data.dsize = pblob->length;
 234         return dbwrap_record_store(rec, data, 0);
 235 }
 236
 237 /*********************************************************************
 238  On unlink we need to delete the tdb record (if using tdb).
 239 *********************************************************************/
 240
 241 static int unlink_acl_tdb(vfs_handle_struct *handle,
 242                           const struct smb_filename *smb_fname)
 243 {
 244         struct smb_filename *smb_fname_tmp = NULL;
 245         struct db_context *db = acl_db;
 246         int ret = -1;
 247
 248         smb_fname_tmp = cp_smb_filename_nostream(talloc_tos(), smb_fname);
 249         if (smb_fname_tmp == NULL) {
 250                 errno = ENOMEM;
 251                 goto out;
 252         }
 253
 254         if (smb_fname_tmp->flags & SMB_FILENAME_POSIX_PATH) {
 255                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
 256         } else {
 257                 ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
 258         }
 259
 260         if (ret == -1) {
 261                 goto out;
 262         }
 263
 264         ret = unlink_acl_common(handle, smb_fname_tmp);
 265
 266         if (ret == -1) {
 267                 goto out;
 268         }
 269
 270         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 271  out:
 272         return ret;
 273 }
 274
 275 /*********************************************************************
 276  On rmdir we need to delete the tdb record (if using tdb).
 277 *********************************************************************/
 278
 279 static int rmdir_acl_tdb(vfs_handle_struct *handle,
 280                 const struct smb_filename *smb_fname)
 281 {
 282
 283         SMB_STRUCT_STAT sbuf;
 284         struct db_context *db = acl_db;
 285         int ret = -1;
 286
 287         ret = vfs_stat_smb_basename(handle->conn, smb_fname, &sbuf);
 288         if (ret == -1) {
 289                 return -1;
 290         }
 291
 292         ret = rmdir_acl_common(handle, smb_fname);
 293         if (ret == -1) {
 294                 return -1;
 295         }
 296
 297         acl_tdb_delete(handle, db, &sbuf);
 298         return 0;
 299 }
 300
 301 /*******************************************************************
 302  Handle opening the storage tdb if so configured.
 303 *******************************************************************/
 304
 305 static int connect_acl_tdb(struct vfs_handle_struct *handle,
 306                                 const char *service,
 307                                 const char *user)
 308 {
 309         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
 310         bool ok;
 311         struct acl_common_config *config = NULL;
 312
 313         if (ret < 0) {
 314                 return ret;
 315         }
 316
 317         if (!acl_tdb_init()) {
 318                 SMB_VFS_NEXT_DISCONNECT(handle);
 319                 return -1;
 320         }
 321
 322         ok = init_acl_common_config(handle, ACL_MODULE_NAME);
 323         if (!ok) {
 324                 DBG_ERR("init_acl_common_config failed\n");
 325                 return -1;
 326         }
 327
 328         /* Ensure we have the parameters correct if we're
 329          * using this module. */
 330         DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
 331                 "'dos filemode = true' and "
 332                 "'force unknown acl user = true' for service %s\n",
 333                 service ));
 334
 335         lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
 336         lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");
 337         lp_do_parameter(SNUM(handle->conn), "force unknown acl user", "true");
 338
 339         SMB_VFS_HANDLE_GET_DATA(handle, config,
 340                                 struct acl_common_config,
 341                                 return -1);
 342
 343         if (config->ignore_system_acls) {
 344                 mode_t create_mask = lp_create_mask(SNUM(handle->conn));
 345                 char *create_mask_str = NULL;
 346
 347                 if ((create_mask & 0666) != 0666) {
 348                         create_mask |= 0666;
 349                         create_mask_str = talloc_asprintf(handle, "0%o",
 350                                                           create_mask);
 351                         if (create_mask_str == NULL) {
 352                                 DBG_ERR("talloc_asprintf failed\n");
 353                                 return -1;
 354                         }
 355
 356                         DBG_NOTICE("setting 'create mask = %s'\n", create_mask_str);
 357
 358                         lp_do_parameter (SNUM(handle->conn),
 359                                         "create mask", create_mask_str);
 360
 361                         TALLOC_FREE(create_mask_str);
 362                 }
 363
 364                 DBG_NOTICE("setting 'directory mask = 0777', "
 365                            "'store dos attributes = yes' and all "
 366                            "'map ...' options to 'no'\n");
 367
 368                 lp_do_parameter(SNUM(handle->conn), "directory mask", "0777");
 369                 lp_do_parameter(SNUM(handle->conn), "map archive", "no");
 370                 lp_do_parameter(SNUM(handle->conn), "map hidden", "no");
 371                 lp_do_parameter(SNUM(handle->conn), "map readonly", "no");
 372                 lp_do_parameter(SNUM(handle->conn), "map system", "no");
 373                 lp_do_parameter(SNUM(handle->conn), "store dos attributes",
 374                                 "yes");
 375         }
 376
 377         return 0;
 378 }
 379
 380 /*********************************************************************
 381  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 382 *********************************************************************/
 383
 384 static int sys_acl_set_file_tdb(vfs_handle_struct *handle,
 385                         const struct smb_filename *smb_fname_in,
 386                         SMB_ACL_TYPE_T type,
 387                         SMB_ACL_T theacl)
 388 {
 389         struct db_context *db = acl_db;
 390         int ret = -1;
 391         int saved_errno = 0;
 392         struct smb_filename *smb_fname = NULL;
 393
 394         smb_fname = cp_smb_filename_nostream(talloc_tos(), smb_fname_in);
 395         if (smb_fname == NULL) {
 396                 return -1;
 397         };
 398
 399         ret = SMB_VFS_STAT(handle->conn, smb_fname);
 400         if (ret == -1) {
 401                 saved_errno = errno;
 402                 goto fail;
 403         }
 404
 405         ret = SMB_VFS_NEXT_SYS_ACL_SET_FILE(handle,
 406                                                 smb_fname,
 407                                                 type,
 408                                                 theacl);
 409         if (ret == -1) {
 410                 saved_errno = errno;
 411                 goto fail;
 412         }
 413
 414         acl_tdb_delete(handle, db, &smb_fname->st);
 415
 416 fail:
 417         TALLOC_FREE(smb_fname);
 418
 419         if (saved_errno != 0) {
 420                 errno = saved_errno;
 421         }
 422         return ret;
 423 }
 424
 425 /*********************************************************************
 426  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 427 *********************************************************************/
 428
 429 static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
 430                             files_struct *fsp,
 431                             SMB_ACL_T theacl)
 432 {
 433         struct db_context *db = acl_db;
 434         NTSTATUS status;
 435         int ret;
 436
 437         status = vfs_stat_fsp(fsp);
 438         if (!NT_STATUS_IS_OK(status)) {
 439                 return -1;
 440         }
 441
 442         ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
 443                                                 fsp,
 444                                                 theacl);
 445         if (ret == -1) {
 446                 return -1;
 447         }
 448
 449         acl_tdb_delete(handle, db, &fsp->fsp_name->st);
 450         return 0;
 451 }
 452
 453 static NTSTATUS acl_tdb_fget_nt_acl(vfs_handle_struct *handle,
 454                                     files_struct *fsp,
 455                                     uint32_t security_info,
 456                                     TALLOC_CTX *mem_ctx,
 457                                     struct security_descriptor **ppdesc)
 458 {
 459         NTSTATUS status;
 460         status = get_nt_acl_common(get_acl_blob, handle, fsp, NULL,
 461                                    security_info, mem_ctx, ppdesc);
 462         return status;
 463 }
 464
 465 static NTSTATUS acl_tdb_get_nt_acl(vfs_handle_struct *handle,
 466                                    const struct smb_filename *smb_fname,
 467                                    uint32_t security_info,
 468                                    TALLOC_CTX *mem_ctx,
 469                                    struct security_descriptor **ppdesc)
 470 {
 471         NTSTATUS status;
 472         status = get_nt_acl_common(get_acl_blob, handle, NULL, smb_fname,
 473                                    security_info, mem_ctx, ppdesc);
 474         return status;
 475 }
 476
 477 static NTSTATUS acl_tdb_fset_nt_acl(vfs_handle_struct *handle,
 478                                     files_struct *fsp,
 479                                     uint32_t security_info_sent,
 480                                     const struct security_descriptor *psd)
 481 {
 482         NTSTATUS status;
 483         status = fset_nt_acl_common(get_acl_blob, store_acl_blob_fsp,
 484                                     ACL_MODULE_NAME,
 485                                     handle, fsp, security_info_sent, psd);
 486         return status;
 487 }
 488
 489 static struct vfs_fn_pointers vfs_acl_tdb_fns = {
 490         .connect_fn = connect_acl_tdb,
 491         .disconnect_fn = disconnect_acl_tdb,
 492         .rmdir_fn = rmdir_acl_tdb,
 493         .unlink_fn = unlink_acl_tdb,
 494         .chmod_fn = chmod_acl_module_common,
 495         .fchmod_fn = fchmod_acl_module_common,
 496         .fget_nt_acl_fn = acl_tdb_fget_nt_acl,
 497         .get_nt_acl_fn = acl_tdb_get_nt_acl,
 498         .fset_nt_acl_fn = acl_tdb_fset_nt_acl,
 499         .sys_acl_set_file_fn = sys_acl_set_file_tdb,
 500         .sys_acl_set_fd_fn = sys_acl_set_fd_tdb
 501 };
 502
 503 static_decl_vfs;
 504 NTSTATUS vfs_acl_tdb_init(TALLOC_CTX *ctx)
 505 {
 506         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
 507                                 &vfs_acl_tdb_fns);
 508 }