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 /* NOTE: This is an experimental module, not yet finished. JRA. */
  22
  23 #include "includes.h"
  24 #include "librpc/gen_ndr/xattr.h"
  25 #include "librpc/gen_ndr/ndr_xattr.h"
  26 #include "../lib/crypto/crypto.h"
  27
  28 #undef DBGC_CLASS
  29 #define DBGC_CLASS DBGC_VFS
  30
  31 #define ACL_MODULE_NAME "acl_tdb"
  32 #include "modules/vfs_acl_common.c"
  33
  34 static unsigned int ref_count;
  35 static struct db_context *acl_db;
  36
  37 /*******************************************************************
  38  Open acl_db if not already open, increment ref count.
  39 *******************************************************************/
  40
  41 static bool acl_tdb_init(void)
  42 {
  43         char *dbname;
  44
  45         if (acl_db) {
  46                 ref_count++;
  47                 return true;
  48         }
  49
  50         dbname = state_path("file_ntacls.tdb");
  51
  52         if (dbname == NULL) {
  53                 errno = ENOSYS;
  54                 return false;
  55         }
  56
  57         become_root();
  58         acl_db = db_open(NULL, dbname, 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600);
  59         unbecome_root();
  60
  61         if (acl_db == NULL) {
  62 #if defined(ENOTSUP)
  63                 errno = ENOTSUP;
  64 #else
  65                 errno = ENOSYS;
  66 #endif
  67                 TALLOC_FREE(dbname);
  68                 return false;
  69         }
  70
  71         ref_count++;
  72         TALLOC_FREE(dbname);
  73         return true;
  74 }
  75
  76 /*******************************************************************
  77  Lower ref count and close acl_db if zero.
  78 *******************************************************************/
  79
  80 static void disconnect_acl_tdb(struct vfs_handle_struct *handle)
  81 {
  82         SMB_VFS_NEXT_DISCONNECT(handle);
  83         ref_count--;
  84         if (ref_count == 0) {
  85                 TALLOC_FREE(acl_db);
  86         }
  87 }
  88
  89 /*******************************************************************
  90  Fetch_lock the tdb acl record for a file
  91 *******************************************************************/
  92
  93 static struct db_record *acl_tdb_lock(TALLOC_CTX *mem_ctx,
  94                                         struct db_context *db,
  95                                         const struct file_id *id)
  96 {
  97         uint8 id_buf[16];
  98
  99         /* For backwards compatibility only store the dev/inode. */
 100         push_file_id_16((char *)id_buf, id);
 101         return db->fetch_locked(db,
 102                                 mem_ctx,
 103                                 make_tdb_data(id_buf,
 104                                         sizeof(id_buf)));
 105 }
 106
 107 /*******************************************************************
 108  Delete the tdb acl record for a file
 109 *******************************************************************/
 110
 111 static NTSTATUS acl_tdb_delete(vfs_handle_struct *handle,
 112                                 struct db_context *db,
 113                                 SMB_STRUCT_STAT *psbuf)
 114 {
 115         NTSTATUS status;
 116         struct file_id id = vfs_file_id_from_sbuf(handle->conn, psbuf);
 117         struct db_record *rec = acl_tdb_lock(talloc_tos(), db, &id);
 118
 119         /*
 120          * If rec == NULL there's not much we can do about it
 121          */
 122
 123         if (rec == NULL) {
 124                 DEBUG(10,("acl_tdb_delete: rec == NULL\n"));
 125                 TALLOC_FREE(rec);
 126                 return NT_STATUS_OK;
 127         }
 128
 129         status = rec->delete_rec(rec);
 130         TALLOC_FREE(rec);
 131         return status;
 132 }
 133
 134 /*******************************************************************
 135  Pull a security descriptor into a DATA_BLOB from a tdb store.
 136 *******************************************************************/
 137
 138 static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
 139                         vfs_handle_struct *handle,
 140                         files_struct *fsp,
 141                         const char *name,
 142                         DATA_BLOB *pblob)
 143 {
 144         uint8 id_buf[16];
 145         TDB_DATA data;
 146         struct file_id id;
 147         struct db_context *db = acl_db;
 148         NTSTATUS status = NT_STATUS_OK;
 149         SMB_STRUCT_STAT sbuf;
 150
 151         ZERO_STRUCT(sbuf);
 152
 153         if (fsp) {
 154                 status = vfs_stat_fsp(fsp);
 155                 sbuf = fsp->fsp_name->st;
 156         } else {
 157                 int ret = vfs_stat_smb_fname(handle->conn, name, &sbuf);
 158                 if (ret == -1) {
 159                         status = map_nt_error_from_unix(errno);
 160                 }
 161         }
 162
 163         if (!NT_STATUS_IS_OK(status)) {
 164                 return status;
 165         }
 166
 167         id = vfs_file_id_from_sbuf(handle->conn, &sbuf);
 168
 169         /* For backwards compatibility only store the dev/inode. */
 170         push_file_id_16((char *)id_buf, &id);
 171
 172         if (db->fetch(db,
 173                         ctx,
 174                         make_tdb_data(id_buf, sizeof(id_buf)),
 175                         &data) == -1) {
 176                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 177         }
 178
 179         pblob->data = data.dptr;
 180         pblob->length = data.dsize;
 181
 182         DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
 183                 (unsigned int)data.dsize, name ));
 184
 185         if (pblob->length == 0 || pblob->data == NULL) {
 186                 return NT_STATUS_NOT_FOUND;
 187         }
 188         return NT_STATUS_OK;
 189 }
 190
 191 /*******************************************************************
 192  Store a DATA_BLOB into a tdb record given an fsp pointer.
 193 *******************************************************************/
 194
 195 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
 196                                 files_struct *fsp,
 197                                 DATA_BLOB *pblob)
 198 {
 199         uint8 id_buf[16];
 200         struct file_id id;
 201         TDB_DATA data;
 202         struct db_context *db = acl_db;
 203         struct db_record *rec;
 204         NTSTATUS status;
 205
 206         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
 207                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
 208
 209         status = vfs_stat_fsp(fsp);
 210         if (!NT_STATUS_IS_OK(status)) {
 211                 return status;
 212         }
 213
 214         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 215
 216         /* For backwards compatibility only store the dev/inode. */
 217         push_file_id_16((char *)id_buf, &id);
 218         rec = db->fetch_locked(db, talloc_tos(),
 219                                 make_tdb_data(id_buf,
 220                                         sizeof(id_buf)));
 221         if (rec == NULL) {
 222                 DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
 223                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 224         }
 225         data.dptr = pblob->data;
 226         data.dsize = pblob->length;
 227         return rec->store(rec, data, 0);
 228 }
 229
 230 /*********************************************************************
 231  On unlink we need to delete the tdb record (if using tdb).
 232 *********************************************************************/
 233
 234 static int unlink_acl_tdb(vfs_handle_struct *handle,
 235                           const struct smb_filename *smb_fname)
 236 {
 237         struct smb_filename *smb_fname_tmp = NULL;
 238         struct db_context *db = acl_db;
 239         NTSTATUS status;
 240         int ret = -1;
 241
 242         status = copy_smb_filename(talloc_tos(), smb_fname, &smb_fname_tmp);
 243         if (!NT_STATUS_IS_OK(status)) {
 244                 errno = map_errno_from_nt_status(status);
 245                 goto out;
 246         }
 247
 248         if (lp_posix_pathnames()) {
 249                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
 250         } else {
 251                 ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
 252         }
 253
 254         if (ret == -1) {
 255                 goto out;
 256         }
 257
 258         ret = unlink_acl_common(handle, smb_fname_tmp);
 259
 260         if (ret == -1) {
 261                 goto out;
 262         }
 263
 264         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 265  out:
 266         return ret;
 267 }
 268
 269 /*********************************************************************
 270  On rmdir we need to delete the tdb record (if using tdb).
 271 *********************************************************************/
 272
 273 static int rmdir_acl_tdb(vfs_handle_struct *handle, const char *path)
 274 {
 275
 276         SMB_STRUCT_STAT sbuf;
 277         struct db_context *db = acl_db;
 278         int ret = -1;
 279
 280         if (lp_posix_pathnames()) {
 281                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 282         } else {
 283                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 284         }
 285
 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         if (lp_posix_pathnames()) {
 346                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 347         } else {
 348                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 349         }
 350
 351         if (ret == -1) {
 352                 return -1;
 353         }
 354
 355         ret = SMB_VFS_NEXT_SYS_ACL_SET_FILE(handle,
 356                                                 path,
 357                                                 type,
 358                                                 theacl);
 359         if (ret == -1) {
 360                 return -1;
 361         }
 362
 363         acl_tdb_delete(handle, db, &sbuf);
 364         return 0;
 365 }
 366
 367 /*********************************************************************
 368  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 369 *********************************************************************/
 370
 371 static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
 372                             files_struct *fsp,
 373                             SMB_ACL_T theacl)
 374 {
 375         struct db_context *db = acl_db;
 376         NTSTATUS status;
 377         int ret;
 378
 379         status = vfs_stat_fsp(fsp);
 380         if (!NT_STATUS_IS_OK(status)) {
 381                 return -1;
 382         }
 383
 384         ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
 385                                                 fsp,
 386                                                 theacl);
 387         if (ret == -1) {
 388                 return -1;
 389         }
 390
 391         acl_tdb_delete(handle, db, &fsp->fsp_name->st);
 392         return 0;
 393 }
 394
 395 static struct vfs_fn_pointers vfs_acl_tdb_fns = {
 396         .connect_fn = connect_acl_tdb,
 397         .disconnect = disconnect_acl_tdb,
 398         .opendir = opendir_acl_common,
 399         .mkdir = mkdir_acl_common,
 400         .rmdir = rmdir_acl_tdb,
 401         .open = open_acl_common,
 402         .create_file = create_file_acl_common,
 403         .unlink = unlink_acl_tdb,
 404         .chmod = chmod_acl_module_common,
 405         .fchmod = fchmod_acl_module_common,
 406         .fget_nt_acl = fget_nt_acl_common,
 407         .get_nt_acl = get_nt_acl_common,
 408         .fset_nt_acl = fset_nt_acl_common,
 409         .chmod_acl = chmod_acl_acl_module_common,
 410         .fchmod_acl = fchmod_acl_acl_module_common,
 411         .sys_acl_set_file = sys_acl_set_file_tdb,
 412         .sys_acl_set_fd = sys_acl_set_fd_tdb
 413 };
 414
 415 NTSTATUS vfs_acl_tdb_init(void)
 416 {
 417         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
 418                                 &vfs_acl_tdb_fns);
 419 }