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 "librpc/gen_ndr/ndr_xattr.h"
  26 #include "../lib/crypto/crypto.h"
  27 #include "dbwrap/dbwrap.h"
  28 #include "dbwrap/dbwrap_open.h"
  29 #include "auth.h"
  30 #include "util_tdb.h"
  31
  32 #undef DBGC_CLASS
  33 #define DBGC_CLASS DBGC_VFS
  34
  35 #define ACL_MODULE_NAME "acl_tdb"
  36 #include "modules/vfs_acl_common.c"
  37
  38 static unsigned int ref_count;
  39 static struct db_context *acl_db;
  40
  41 /*******************************************************************
  42  Open acl_db if not already open, increment ref count.
  43 *******************************************************************/
  44
  45 static bool acl_tdb_init(void)
  46 {
  47         char *dbname;
  48
  49         if (acl_db) {
  50                 ref_count++;
  51                 return true;
  52         }
  53
  54         dbname = state_path("file_ntacls.tdb");
  55
  56         if (dbname == NULL) {
  57                 errno = ENOSYS;
  58                 return false;
  59         }
  60
  61         become_root();
  62         acl_db = db_open(NULL, dbname, 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600,
  63                          DBWRAP_LOCK_ORDER_1, DBWRAP_FLAG_NONE);
  64         unbecome_root();
  65
  66         if (acl_db == NULL) {
  67 #if defined(ENOTSUP)
  68                 errno = ENOTSUP;
  69 #else
  70                 errno = ENOSYS;
  71 #endif
  72                 TALLOC_FREE(dbname);
  73                 return false;
  74         }
  75
  76         ref_count++;
  77         TALLOC_FREE(dbname);
  78         return true;
  79 }
  80
  81 /*******************************************************************
  82  Lower ref count and close acl_db if zero.
  83 *******************************************************************/
  84
  85 static void disconnect_acl_tdb(struct vfs_handle_struct *handle)
  86 {
  87         SMB_VFS_NEXT_DISCONNECT(handle);
  88         ref_count--;
  89         if (ref_count == 0) {
  90                 TALLOC_FREE(acl_db);
  91         }
  92 }
  93
  94 /*******************************************************************
  95  Fetch_lock the tdb acl record for a file
  96 *******************************************************************/
  97
  98 static struct db_record *acl_tdb_lock(TALLOC_CTX *mem_ctx,
  99                                         struct db_context *db,
 100                                         const struct file_id *id)
 101 {
 102         uint8 id_buf[16];
 103
 104         /* For backwards compatibility only store the dev/inode. */
 105         push_file_id_16((char *)id_buf, id);
 106         return dbwrap_fetch_locked(db,
 107                                    mem_ctx,
 108                                    make_tdb_data(id_buf,
 109                                                  sizeof(id_buf)));
 110 }
 111
 112 /*******************************************************************
 113  Delete the tdb acl record for a file
 114 *******************************************************************/
 115
 116 static NTSTATUS acl_tdb_delete(vfs_handle_struct *handle,
 117                                 struct db_context *db,
 118                                 SMB_STRUCT_STAT *psbuf)
 119 {
 120         NTSTATUS status;
 121         struct file_id id = vfs_file_id_from_sbuf(handle->conn, psbuf);
 122         struct db_record *rec = acl_tdb_lock(talloc_tos(), db, &id);
 123
 124         /*
 125          * If rec == NULL there's not much we can do about it
 126          */
 127
 128         if (rec == NULL) {
 129                 DEBUG(10,("acl_tdb_delete: rec == NULL\n"));
 130                 TALLOC_FREE(rec);
 131                 return NT_STATUS_OK;
 132         }
 133
 134         status = dbwrap_record_delete(rec);
 135         TALLOC_FREE(rec);
 136         return status;
 137 }
 138
 139 /*******************************************************************
 140  Pull a security descriptor into a DATA_BLOB from a tdb store.
 141 *******************************************************************/
 142
 143 static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
 144                         vfs_handle_struct *handle,
 145                         files_struct *fsp,
 146                         const char *name,
 147                         DATA_BLOB *pblob)
 148 {
 149         uint8 id_buf[16];
 150         TDB_DATA data;
 151         struct file_id id;
 152         struct db_context *db = acl_db;
 153         NTSTATUS status = NT_STATUS_OK;
 154         SMB_STRUCT_STAT sbuf;
 155
 156         ZERO_STRUCT(sbuf);
 157
 158         if (fsp) {
 159                 status = vfs_stat_fsp(fsp);
 160                 sbuf = fsp->fsp_name->st;
 161         } else {
 162                 int ret = vfs_stat_smb_basename(handle->conn, name, &sbuf);
 163                 if (ret == -1) {
 164                         status = map_nt_error_from_unix(errno);
 165                 }
 166         }
 167
 168         if (!NT_STATUS_IS_OK(status)) {
 169                 return status;
 170         }
 171
 172         id = vfs_file_id_from_sbuf(handle->conn, &sbuf);
 173
 174         /* For backwards compatibility only store the dev/inode. */
 175         push_file_id_16((char *)id_buf, &id);
 176
 177         status = dbwrap_fetch(db,
 178                               ctx,
 179                               make_tdb_data(id_buf, sizeof(id_buf)),
 180                               &data);
 181         if (!NT_STATUS_IS_OK(status)) {
 182                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 183         }
 184
 185         pblob->data = data.dptr;
 186         pblob->length = data.dsize;
 187
 188         DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
 189                 (unsigned int)data.dsize, name ));
 190
 191         if (pblob->length == 0 || pblob->data == NULL) {
 192                 return NT_STATUS_NOT_FOUND;
 193         }
 194         return NT_STATUS_OK;
 195 }
 196
 197 /*******************************************************************
 198  Store a DATA_BLOB into a tdb record given an fsp pointer.
 199 *******************************************************************/
 200
 201 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
 202                                 files_struct *fsp,
 203                                 DATA_BLOB *pblob)
 204 {
 205         uint8 id_buf[16];
 206         struct file_id id;
 207         TDB_DATA data;
 208         struct db_context *db = acl_db;
 209         struct db_record *rec;
 210         NTSTATUS status;
 211
 212         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
 213                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
 214
 215         status = vfs_stat_fsp(fsp);
 216         if (!NT_STATUS_IS_OK(status)) {
 217                 return status;
 218         }
 219
 220         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 221
 222         /* For backwards compatibility only store the dev/inode. */
 223         push_file_id_16((char *)id_buf, &id);
 224         rec = dbwrap_fetch_locked(db, talloc_tos(),
 225                                   make_tdb_data(id_buf,
 226                                                 sizeof(id_buf)));
 227         if (rec == NULL) {
 228                 DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
 229                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 230         }
 231         data.dptr = pblob->data;
 232         data.dsize = pblob->length;
 233         return dbwrap_record_store(rec, data, 0);
 234 }
 235
 236 /*********************************************************************
 237  On unlink we need to delete the tdb record (if using tdb).
 238 *********************************************************************/
 239
 240 static int unlink_acl_tdb(vfs_handle_struct *handle,
 241                           const struct smb_filename *smb_fname)
 242 {
 243         struct smb_filename *smb_fname_tmp = NULL;
 244         struct db_context *db = acl_db;
 245         int ret = -1;
 246
 247         smb_fname_tmp = cp_smb_filename(talloc_tos(), smb_fname);
 248         if (smb_fname_tmp == NULL) {
 249                 errno = ENOMEM;
 250                 goto out;
 251         }
 252
 253         if (lp_posix_pathnames()) {
 254                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
 255         } else {
 256                 ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
 257         }
 258
 259         if (ret == -1) {
 260                 goto out;
 261         }
 262
 263         ret = unlink_acl_common(handle, smb_fname_tmp);
 264
 265         if (ret == -1) {
 266                 goto out;
 267         }
 268
 269         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 270  out:
 271         return ret;
 272 }
 273
 274 /*********************************************************************
 275  On rmdir we need to delete the tdb record (if using tdb).
 276 *********************************************************************/
 277
 278 static int rmdir_acl_tdb(vfs_handle_struct *handle, const char *path)
 279 {
 280
 281         SMB_STRUCT_STAT sbuf;
 282         struct db_context *db = acl_db;
 283         int ret = -1;
 284
 285         ret = vfs_stat_smb_basename(handle->conn, path, &sbuf);
 286         if (ret == -1) {
 287                 return -1;
 288         }
 289
 290         ret = rmdir_acl_common(handle, path);
 291         if (ret == -1) {
 292                 return -1;
 293         }
 294
 295         acl_tdb_delete(handle, db, &sbuf);
 296         return 0;
 297 }
 298
 299 /*******************************************************************
 300  Handle opening the storage tdb if so configured.
 301 *******************************************************************/
 302
 303 static int connect_acl_tdb(struct vfs_handle_struct *handle,
 304                                 const char *service,
 305                                 const char *user)
 306 {
 307         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
 308
 309         if (ret < 0) {
 310                 return ret;
 311         }
 312
 313         if (!acl_tdb_init()) {
 314                 SMB_VFS_NEXT_DISCONNECT(handle);
 315                 return -1;
 316         }
 317
 318         /* Ensure we have the parameters correct if we're
 319          * using this module. */
 320         DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
 321                 "'dos filemode = true' and "
 322                 "'force unknown acl user = true' for service %s\n",
 323                 service ));
 324
 325         lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
 326         lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");
 327         lp_do_parameter(SNUM(handle->conn), "force unknown acl user", "true");
 328
 329         return 0;
 330 }
 331
 332 /*********************************************************************
 333  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 334 *********************************************************************/
 335
 336 static int sys_acl_set_file_tdb(vfs_handle_struct *handle,
 337                               const char *path,
 338                               SMB_ACL_TYPE_T type,
 339                               SMB_ACL_T theacl)
 340 {
 341         SMB_STRUCT_STAT sbuf;
 342         struct db_context *db = acl_db;
 343         int ret = -1;
 344
 345         ret = vfs_stat_smb_basename(handle->conn, path, &sbuf);
 346         if (ret == -1) {
 347                 return -1;
 348         }
 349
 350         ret = SMB_VFS_NEXT_SYS_ACL_SET_FILE(handle,
 351                                                 path,
 352                                                 type,
 353                                                 theacl);
 354         if (ret == -1) {
 355                 return -1;
 356         }
 357
 358         acl_tdb_delete(handle, db, &sbuf);
 359         return 0;
 360 }
 361
 362 /*********************************************************************
 363  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 364 *********************************************************************/
 365
 366 static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
 367                             files_struct *fsp,
 368                             SMB_ACL_T theacl)
 369 {
 370         struct db_context *db = acl_db;
 371         NTSTATUS status;
 372         int ret;
 373
 374         status = vfs_stat_fsp(fsp);
 375         if (!NT_STATUS_IS_OK(status)) {
 376                 return -1;
 377         }
 378
 379         ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
 380                                                 fsp,
 381                                                 theacl);
 382         if (ret == -1) {
 383                 return -1;
 384         }
 385
 386         acl_tdb_delete(handle, db, &fsp->fsp_name->st);
 387         return 0;
 388 }
 389
 390 static struct vfs_fn_pointers vfs_acl_tdb_fns = {
 391         .connect_fn = connect_acl_tdb,
 392         .disconnect_fn = disconnect_acl_tdb,
 393         .rmdir_fn = rmdir_acl_tdb,
 394         .unlink_fn = unlink_acl_tdb,
 395         .chmod_fn = chmod_acl_module_common,
 396         .fchmod_fn = fchmod_acl_module_common,
 397         .fget_nt_acl_fn = fget_nt_acl_common,
 398         .get_nt_acl_fn = get_nt_acl_common,
 399         .fset_nt_acl_fn = fset_nt_acl_common,
 400         .chmod_acl_fn = chmod_acl_acl_module_common,
 401         .fchmod_acl_fn = fchmod_acl_acl_module_common,
 402         .sys_acl_set_file_fn = sys_acl_set_file_tdb,
 403         .sys_acl_set_fd_fn = sys_acl_set_fd_tdb
 404 };
 405
 406 NTSTATUS vfs_acl_tdb_init(void)
 407 {
 408         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
 409                                 &vfs_acl_tdb_fns);
 410 }