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 "smbd/smbd.h"
  25 #include "system/filesys.h"
  26 #include "librpc/gen_ndr/xattr.h"
  27 #include "librpc/gen_ndr/ndr_xattr.h"
  28 #include "../lib/crypto/crypto.h"
  29 #include "dbwrap.h"
  30 #include "auth.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         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 id_buf[16];
 102
 103         /* For backwards compatibility only store the dev/inode. */
 104         push_file_id_16((char *)id_buf, id);
 105         return db->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 = rec->delete_rec(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 char *name,
 146                         DATA_BLOB *pblob)
 147 {
 148         uint8 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_fname(handle->conn, name, &sbuf);
 162                 if (ret == -1) {
 163                         status = map_nt_error_from_unix(errno);
 164                 }
 165         }
 166
 167         if (!NT_STATUS_IS_OK(status)) {
 168                 return status;
 169         }
 170
 171         id = vfs_file_id_from_sbuf(handle->conn, &sbuf);
 172
 173         /* For backwards compatibility only store the dev/inode. */
 174         push_file_id_16((char *)id_buf, &id);
 175
 176         if (db->fetch(db,
 177                         ctx,
 178                         make_tdb_data(id_buf, sizeof(id_buf)),
 179                         &data) == -1) {
 180                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 181         }
 182
 183         pblob->data = data.dptr;
 184         pblob->length = data.dsize;
 185
 186         DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
 187                 (unsigned int)data.dsize, name ));
 188
 189         if (pblob->length == 0 || pblob->data == NULL) {
 190                 return NT_STATUS_NOT_FOUND;
 191         }
 192         return NT_STATUS_OK;
 193 }
 194
 195 /*******************************************************************
 196  Store a DATA_BLOB into a tdb record given an fsp pointer.
 197 *******************************************************************/
 198
 199 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
 200                                 files_struct *fsp,
 201                                 DATA_BLOB *pblob)
 202 {
 203         uint8 id_buf[16];
 204         struct file_id id;
 205         TDB_DATA data;
 206         struct db_context *db = acl_db;
 207         struct db_record *rec;
 208         NTSTATUS status;
 209
 210         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
 211                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
 212
 213         status = vfs_stat_fsp(fsp);
 214         if (!NT_STATUS_IS_OK(status)) {
 215                 return status;
 216         }
 217
 218         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 219
 220         /* For backwards compatibility only store the dev/inode. */
 221         push_file_id_16((char *)id_buf, &id);
 222         rec = db->fetch_locked(db, talloc_tos(),
 223                                 make_tdb_data(id_buf,
 224                                         sizeof(id_buf)));
 225         if (rec == NULL) {
 226                 DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
 227                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 228         }
 229         data.dptr = pblob->data;
 230         data.dsize = pblob->length;
 231         return rec->store(rec, data, 0);
 232 }
 233
 234 /*********************************************************************
 235  On unlink we need to delete the tdb record (if using tdb).
 236 *********************************************************************/
 237
 238 static int unlink_acl_tdb(vfs_handle_struct *handle,
 239                           const struct smb_filename *smb_fname)
 240 {
 241         struct smb_filename *smb_fname_tmp = NULL;
 242         struct db_context *db = acl_db;
 243         NTSTATUS status;
 244         int ret = -1;
 245
 246         status = copy_smb_filename(talloc_tos(), smb_fname, &smb_fname_tmp);
 247         if (!NT_STATUS_IS_OK(status)) {
 248                 errno = map_errno_from_nt_status(status);
 249                 goto out;
 250         }
 251
 252         if (lp_posix_pathnames()) {
 253                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
 254         } else {
 255                 ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
 256         }
 257
 258         if (ret == -1) {
 259                 goto out;
 260         }
 261
 262         ret = unlink_acl_common(handle, smb_fname_tmp);
 263
 264         if (ret == -1) {
 265                 goto out;
 266         }
 267
 268         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 269  out:
 270         return ret;
 271 }
 272
 273 /*********************************************************************
 274  On rmdir we need to delete the tdb record (if using tdb).
 275 *********************************************************************/
 276
 277 static int rmdir_acl_tdb(vfs_handle_struct *handle, const char *path)
 278 {
 279
 280         SMB_STRUCT_STAT sbuf;
 281         struct db_context *db = acl_db;
 282         int ret = -1;
 283
 284         if (lp_posix_pathnames()) {
 285                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 286         } else {
 287                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 288         }
 289
 290         if (ret == -1) {
 291                 return -1;
 292         }
 293
 294         ret = rmdir_acl_common(handle, path);
 295         if (ret == -1) {
 296                 return -1;
 297         }
 298
 299         acl_tdb_delete(handle, db, &sbuf);
 300         return 0;
 301 }
 302
 303 /*******************************************************************
 304  Handle opening the storage tdb if so configured.
 305 *******************************************************************/
 306
 307 static int connect_acl_tdb(struct vfs_handle_struct *handle,
 308                                 const char *service,
 309                                 const char *user)
 310 {
 311         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
 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         /* Ensure we have the parameters correct if we're
 323          * using this module. */
 324         DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
 325                 "'dos filemode = true' and "
 326                 "'force unknown acl user = true' for service %s\n",
 327                 service ));
 328
 329         lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
 330         lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");
 331         lp_do_parameter(SNUM(handle->conn), "force unknown acl user", "true");
 332
 333         return 0;
 334 }
 335
 336 /*********************************************************************
 337  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 338 *********************************************************************/
 339
 340 static int sys_acl_set_file_tdb(vfs_handle_struct *handle,
 341                               const char *path,
 342                               SMB_ACL_TYPE_T type,
 343                               SMB_ACL_T theacl)
 344 {
 345         SMB_STRUCT_STAT sbuf;
 346         struct db_context *db = acl_db;
 347         int ret = -1;
 348
 349         if (lp_posix_pathnames()) {
 350                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 351         } else {
 352                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 353         }
 354
 355         if (ret == -1) {
 356                 return -1;
 357         }
 358
 359         ret = SMB_VFS_NEXT_SYS_ACL_SET_FILE(handle,
 360                                                 path,
 361                                                 type,
 362                                                 theacl);
 363         if (ret == -1) {
 364                 return -1;
 365         }
 366
 367         acl_tdb_delete(handle, db, &sbuf);
 368         return 0;
 369 }
 370
 371 /*********************************************************************
 372  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 373 *********************************************************************/
 374
 375 static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
 376                             files_struct *fsp,
 377                             SMB_ACL_T theacl)
 378 {
 379         struct db_context *db = acl_db;
 380         NTSTATUS status;
 381         int ret;
 382
 383         status = vfs_stat_fsp(fsp);
 384         if (!NT_STATUS_IS_OK(status)) {
 385                 return -1;
 386         }
 387
 388         ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
 389                                                 fsp,
 390                                                 theacl);
 391         if (ret == -1) {
 392                 return -1;
 393         }
 394
 395         acl_tdb_delete(handle, db, &fsp->fsp_name->st);
 396         return 0;
 397 }
 398
 399 static struct vfs_fn_pointers vfs_acl_tdb_fns = {
 400         .connect_fn = connect_acl_tdb,
 401         .disconnect = disconnect_acl_tdb,
 402         .opendir = opendir_acl_common,
 403         .mkdir = mkdir_acl_common,
 404         .rmdir = rmdir_acl_tdb,
 405         .open = open_acl_common,
 406         .create_file = create_file_acl_common,
 407         .unlink = unlink_acl_tdb,
 408         .chmod = chmod_acl_module_common,
 409         .fchmod = fchmod_acl_module_common,
 410         .fget_nt_acl = fget_nt_acl_common,
 411         .get_nt_acl = get_nt_acl_common,
 412         .fset_nt_acl = fset_nt_acl_common,
 413         .chmod_acl = chmod_acl_acl_module_common,
 414         .fchmod_acl = fchmod_acl_acl_module_common,
 415         .sys_acl_set_file = sys_acl_set_file_tdb,
 416         .sys_acl_set_fd = sys_acl_set_fd_tdb
 417 };
 418
 419 NTSTATUS vfs_acl_tdb_init(void)
 420 {
 421         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
 422                                 &vfs_acl_tdb_fns);
 423 }