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/sha256.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_t 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 struct smb_filename *smb_fname,
 147                         DATA_BLOB *pblob)
 148 {
 149         uint8_t 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,
 163                                 smb_fname->base_name,
 164                                 &sbuf);
 165                 if (ret == -1) {
 166                         status = map_nt_error_from_unix(errno);
 167                 }
 168         }
 169
 170         if (!NT_STATUS_IS_OK(status)) {
 171                 return status;
 172         }
 173
 174         id = vfs_file_id_from_sbuf(handle->conn, &sbuf);
 175
 176         /* For backwards compatibility only store the dev/inode. */
 177         push_file_id_16((char *)id_buf, &id);
 178
 179         status = dbwrap_fetch(db,
 180                               ctx,
 181                               make_tdb_data(id_buf, sizeof(id_buf)),
 182                               &data);
 183         if (!NT_STATUS_IS_OK(status)) {
 184                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 185         }
 186
 187         pblob->data = data.dptr;
 188         pblob->length = data.dsize;
 189
 190         DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
 191                 (unsigned int)data.dsize, smb_fname->base_name ));
 192
 193         if (pblob->length == 0 || pblob->data == NULL) {
 194                 return NT_STATUS_NOT_FOUND;
 195         }
 196         return NT_STATUS_OK;
 197 }
 198
 199 /*******************************************************************
 200  Store a DATA_BLOB into a tdb record given an fsp pointer.
 201 *******************************************************************/
 202
 203 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
 204                                 files_struct *fsp,
 205                                 DATA_BLOB *pblob)
 206 {
 207         uint8_t id_buf[16];
 208         struct file_id id;
 209         TDB_DATA data;
 210         struct db_context *db = acl_db;
 211         struct db_record *rec;
 212         NTSTATUS status;
 213
 214         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
 215                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
 216
 217         status = vfs_stat_fsp(fsp);
 218         if (!NT_STATUS_IS_OK(status)) {
 219                 return status;
 220         }
 221
 222         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 223
 224         /* For backwards compatibility only store the dev/inode. */
 225         push_file_id_16((char *)id_buf, &id);
 226         rec = dbwrap_fetch_locked(db, talloc_tos(),
 227                                   make_tdb_data(id_buf,
 228                                                 sizeof(id_buf)));
 229         if (rec == NULL) {
 230                 DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
 231                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 232         }
 233         data.dptr = pblob->data;
 234         data.dsize = pblob->length;
 235         return dbwrap_record_store(rec, data, 0);
 236 }
 237
 238 /*********************************************************************
 239  On unlink we need to delete the tdb record (if using tdb).
 240 *********************************************************************/
 241
 242 static int unlink_acl_tdb(vfs_handle_struct *handle,
 243                           const struct smb_filename *smb_fname)
 244 {
 245         struct smb_filename *smb_fname_tmp = NULL;
 246         struct db_context *db = acl_db;
 247         int ret = -1;
 248
 249         smb_fname_tmp = cp_smb_filename(talloc_tos(), smb_fname);
 250         if (smb_fname_tmp == NULL) {
 251                 errno = ENOMEM;
 252                 goto out;
 253         }
 254
 255         if (smb_fname_tmp->flags & SMB_FILENAME_POSIX_PATH) {
 256                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
 257         } else {
 258                 ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
 259         }
 260
 261         if (ret == -1) {
 262                 goto out;
 263         }
 264
 265         ret = unlink_acl_common(handle, smb_fname_tmp);
 266
 267         if (ret == -1) {
 268                 goto out;
 269         }
 270
 271         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 272  out:
 273         return ret;
 274 }
 275
 276 /*********************************************************************
 277  On rmdir we need to delete the tdb record (if using tdb).
 278 *********************************************************************/
 279
 280 static int rmdir_acl_tdb(vfs_handle_struct *handle,
 281                 const struct smb_filename *smb_fname)
 282 {
 283
 284         SMB_STRUCT_STAT sbuf;
 285         struct db_context *db = acl_db;
 286         int ret = -1;
 287
 288         ret = vfs_stat_smb_basename(handle->conn, smb_fname->base_name, &sbuf);
 289         if (ret == -1) {
 290                 return -1;
 291         }
 292
 293         ret = rmdir_acl_common(handle, smb_fname);
 294         if (ret == -1) {
 295                 return -1;
 296         }
 297
 298         acl_tdb_delete(handle, db, &sbuf);
 299         return 0;
 300 }
 301
 302 /*******************************************************************
 303  Handle opening the storage tdb if so configured.
 304 *******************************************************************/
 305
 306 static int connect_acl_tdb(struct vfs_handle_struct *handle,
 307                                 const char *service,
 308                                 const char *user)
 309 {
 310         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
 311
 312         if (ret < 0) {
 313                 return ret;
 314         }
 315
 316         if (!acl_tdb_init()) {
 317                 SMB_VFS_NEXT_DISCONNECT(handle);
 318                 return -1;
 319         }
 320
 321         /* Ensure we have the parameters correct if we're
 322          * using this module. */
 323         DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
 324                 "'dos filemode = true' and "
 325                 "'force unknown acl user = true' for service %s\n",
 326                 service ));
 327
 328         lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
 329         lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");
 330         lp_do_parameter(SNUM(handle->conn), "force unknown acl user", "true");
 331
 332         return 0;
 333 }
 334
 335 /*********************************************************************
 336  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 337 *********************************************************************/
 338
 339 static int sys_acl_set_file_tdb(vfs_handle_struct *handle,
 340                               const char *path,
 341                               SMB_ACL_TYPE_T type,
 342                               SMB_ACL_T theacl)
 343 {
 344         struct db_context *db = acl_db;
 345         int ret = -1;
 346         struct smb_filename smb_fname = {
 347                 .base_name = discard_const_p(char, path)
 348         };
 349
 350         ret = SMB_VFS_STAT(handle->conn, &smb_fname);
 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, &smb_fname.st);
 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_fn = disconnect_acl_tdb,
 398         .rmdir_fn = rmdir_acl_tdb,
 399         .unlink_fn = unlink_acl_tdb,
 400         .chmod_fn = chmod_acl_module_common,
 401         .fchmod_fn = fchmod_acl_module_common,
 402         .fget_nt_acl_fn = fget_nt_acl_common,
 403         .get_nt_acl_fn = get_nt_acl_common,
 404         .fset_nt_acl_fn = fset_nt_acl_common,
 405         .chmod_acl_fn = chmod_acl_acl_module_common,
 406         .fchmod_acl_fn = fchmod_acl_acl_module_common,
 407         .sys_acl_set_file_fn = sys_acl_set_file_tdb,
 408         .sys_acl_set_fd_fn = sys_acl_set_fd_tdb
 409 };
 410
 411 static_decl_vfs;
 412 NTSTATUS vfs_acl_tdb_init(void)
 413 {
 414         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
 415                                 &vfs_acl_tdb_fns);
 416 }