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 "dbwrap/dbwrap.h"
  26 #include "dbwrap/dbwrap_open.h"
  27 #include "auth.h"
  28 #include "util_tdb.h"
  29 #include "vfs_acl_common.h"
  30
  31 #undef DBGC_CLASS
  32 #define DBGC_CLASS DBGC_VFS
  33
  34 #define ACL_MODULE_NAME "acl_tdb"
  35
  36 static unsigned int ref_count;
  37 static struct db_context *acl_db;
  38
  39 /*******************************************************************
  40  Open acl_db if not already open, increment ref count.
  41 *******************************************************************/
  42
  43 static bool acl_tdb_init(void)
  44 {
  45         char *dbname;
  46
  47         if (acl_db) {
  48                 ref_count++;
  49                 return true;
  50         }
  51
  52         dbname = state_path(talloc_tos(), "file_ntacls.tdb");
  53
  54         if (dbname == NULL) {
  55                 errno = ENOSYS;
  56                 return false;
  57         }
  58
  59         become_root();
  60         acl_db = db_open(NULL, dbname, 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600,
  61                          DBWRAP_LOCK_ORDER_1, DBWRAP_FLAG_NONE);
  62         unbecome_root();
  63
  64         if (acl_db == NULL) {
  65 #if defined(ENOTSUP)
  66                 errno = ENOTSUP;
  67 #else
  68                 errno = ENOSYS;
  69 #endif
  70                 TALLOC_FREE(dbname);
  71                 return false;
  72         }
  73
  74         ref_count++;
  75         TALLOC_FREE(dbname);
  76         return true;
  77 }
  78
  79 /*******************************************************************
  80  Lower ref count and close acl_db if zero.
  81 *******************************************************************/
  82
  83 static void disconnect_acl_tdb(struct vfs_handle_struct *handle)
  84 {
  85         SMB_VFS_NEXT_DISCONNECT(handle);
  86         ref_count--;
  87         if (ref_count == 0) {
  88                 TALLOC_FREE(acl_db);
  89         }
  90 }
  91
  92 /*******************************************************************
  93  Delete the tdb acl record for a file
  94 *******************************************************************/
  95
  96 static NTSTATUS acl_tdb_delete(vfs_handle_struct *handle,
  97                                 struct db_context *db,
  98                                 SMB_STRUCT_STAT *psbuf)
  99 {
 100         NTSTATUS status;
 101         struct file_id id = vfs_file_id_from_sbuf(handle->conn, psbuf);
 102         uint8_t id_buf[16];
 103
 104         /* For backwards compatibility only store the dev/inode. */
 105         push_file_id_16(id_buf, &id);
 106
 107         status = dbwrap_delete(db, make_tdb_data(id_buf, sizeof(id_buf)));
 108         return status;
 109 }
 110
 111 /*******************************************************************
 112  Pull a security descriptor from an fsp into a DATA_BLOB from a tdb store.
 113 *******************************************************************/
 114
 115 static NTSTATUS fget_acl_blob(TALLOC_CTX *ctx,
 116                         vfs_handle_struct *handle,
 117                         files_struct *fsp,
 118                         DATA_BLOB *pblob)
 119 {
 120         uint8_t id_buf[16];
 121         TDB_DATA data;
 122         struct file_id id;
 123         struct db_context *db = acl_db;
 124         NTSTATUS status = NT_STATUS_OK;
 125
 126         status = vfs_stat_fsp(fsp);
 127         if (!NT_STATUS_IS_OK(status)) {
 128                 return status;
 129         }
 130
 131         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 132
 133         /* For backwards compatibility only store the dev/inode. */
 134         push_file_id_16(id_buf, &id);
 135
 136         status = dbwrap_fetch(db,
 137                               ctx,
 138                               make_tdb_data(id_buf, sizeof(id_buf)),
 139                               &data);
 140         if (!NT_STATUS_IS_OK(status)) {
 141                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 142         }
 143
 144         pblob->data = data.dptr;
 145         pblob->length = data.dsize;
 146
 147         DBG_DEBUG("returned %u bytes from file %s\n",
 148                 (unsigned int)data.dsize,
 149                 fsp_str_dbg(fsp));
 150
 151         if (pblob->length == 0 || pblob->data == NULL) {
 152                 return NT_STATUS_NOT_FOUND;
 153         }
 154         return NT_STATUS_OK;
 155 }
 156
 157 /*******************************************************************
 158  Store a DATA_BLOB into a tdb record given an fsp pointer.
 159 *******************************************************************/
 160
 161 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
 162                                 files_struct *fsp,
 163                                 DATA_BLOB *pblob)
 164 {
 165         uint8_t id_buf[16];
 166         struct file_id id;
 167         TDB_DATA data = { .dptr = pblob->data, .dsize = pblob->length };
 168         struct db_context *db = acl_db;
 169         NTSTATUS status;
 170
 171         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
 172                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
 173
 174         status = vfs_stat_fsp(fsp);
 175         if (!NT_STATUS_IS_OK(status)) {
 176                 return status;
 177         }
 178
 179         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 180
 181         /* For backwards compatibility only store the dev/inode. */
 182         push_file_id_16(id_buf, &id);
 183
 184         status = dbwrap_store(
 185                 db, make_tdb_data(id_buf, sizeof(id_buf)), data, 0);
 186         return status;
 187 }
 188
 189 /*********************************************************************
 190  On unlinkat we need to delete the tdb record (if using tdb).
 191 *********************************************************************/
 192
 193 static int unlinkat_acl_tdb(vfs_handle_struct *handle,
 194                         struct files_struct *dirfsp,
 195                         const struct smb_filename *smb_fname,
 196                         int flags)
 197 {
 198         struct smb_filename *smb_fname_tmp = NULL;
 199         struct db_context *db = acl_db;
 200         int ret = -1;
 201
 202         smb_fname_tmp = cp_smb_filename_nostream(talloc_tos(), smb_fname);
 203         if (smb_fname_tmp == NULL) {
 204                 errno = ENOMEM;
 205                 goto out;
 206         }
 207
 208         ret = vfs_stat(handle->conn, smb_fname_tmp);
 209         if (ret == -1) {
 210                 goto out;
 211         }
 212
 213         if (flags & AT_REMOVEDIR) {
 214                 ret = rmdir_acl_common(handle,
 215                                 dirfsp,
 216                                 smb_fname_tmp);
 217         } else {
 218                 ret = unlink_acl_common(handle,
 219                                 dirfsp,
 220                                 smb_fname_tmp,
 221                                 flags);
 222         }
 223
 224         if (ret == -1) {
 225                 goto out;
 226         }
 227
 228         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 229  out:
 230         return ret;
 231 }
 232
 233 /*******************************************************************
 234  Handle opening the storage tdb if so configured.
 235 *******************************************************************/
 236
 237 static int connect_acl_tdb(struct vfs_handle_struct *handle,
 238                                 const char *service,
 239                                 const char *user)
 240 {
 241         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
 242         bool ok;
 243         struct acl_common_config *config = NULL;
 244
 245         if (ret < 0) {
 246                 return ret;
 247         }
 248
 249         if (!acl_tdb_init()) {
 250                 SMB_VFS_NEXT_DISCONNECT(handle);
 251                 return -1;
 252         }
 253
 254         ok = init_acl_common_config(handle, ACL_MODULE_NAME);
 255         if (!ok) {
 256                 DBG_ERR("init_acl_common_config failed\n");
 257                 return -1;
 258         }
 259
 260         /* Ensure we have the parameters correct if we're
 261          * using this module. */
 262         DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
 263                 "'dos filemode = true' and "
 264                 "'force unknown acl user = true' for service %s\n",
 265                 service ));
 266
 267         lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
 268         lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");
 269         lp_do_parameter(SNUM(handle->conn), "force unknown acl user", "true");
 270
 271         SMB_VFS_HANDLE_GET_DATA(handle, config,
 272                                 struct acl_common_config,
 273                                 return -1);
 274
 275         if (config->ignore_system_acls) {
 276                 mode_t create_mask = lp_create_mask(SNUM(handle->conn));
 277                 char *create_mask_str = NULL;
 278
 279                 if ((create_mask & 0666) != 0666) {
 280                         create_mask |= 0666;
 281                         create_mask_str = talloc_asprintf(handle, "0%o",
 282                                                           create_mask);
 283                         if (create_mask_str == NULL) {
 284                                 DBG_ERR("talloc_asprintf failed\n");
 285                                 return -1;
 286                         }
 287
 288                         DBG_NOTICE("setting 'create mask = %s'\n", create_mask_str);
 289
 290                         lp_do_parameter (SNUM(handle->conn),
 291                                         "create mask", create_mask_str);
 292
 293                         TALLOC_FREE(create_mask_str);
 294                 }
 295
 296                 DBG_NOTICE("setting 'directory mask = 0777', "
 297                            "'store dos attributes = yes' and all "
 298                            "'map ...' options to 'no'\n");
 299
 300                 lp_do_parameter(SNUM(handle->conn), "directory mask", "0777");
 301                 lp_do_parameter(SNUM(handle->conn), "map archive", "no");
 302                 lp_do_parameter(SNUM(handle->conn), "map hidden", "no");
 303                 lp_do_parameter(SNUM(handle->conn), "map readonly", "no");
 304                 lp_do_parameter(SNUM(handle->conn), "map system", "no");
 305                 lp_do_parameter(SNUM(handle->conn), "store dos attributes",
 306                                 "yes");
 307         }
 308
 309         return 0;
 310 }
 311
 312 /*********************************************************************
 313  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 314 *********************************************************************/
 315
 316 static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
 317                             files_struct *fsp,
 318                             SMB_ACL_TYPE_T type,
 319                             SMB_ACL_T theacl)
 320 {
 321         struct acl_common_fsp_ext *ext = (struct acl_common_fsp_ext *)
 322                 VFS_FETCH_FSP_EXTENSION(handle, fsp);
 323         struct db_context *db = acl_db;
 324         NTSTATUS status;
 325         int ret;
 326
 327         status = vfs_stat_fsp(fsp);
 328         if (!NT_STATUS_IS_OK(status)) {
 329                 return -1;
 330         }
 331
 332         ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
 333                                           fsp,
 334                                           type,
 335                                           theacl);
 336         if (ret == -1) {
 337                 return -1;
 338         }
 339
 340         if (ext != NULL && ext->setting_nt_acl) {
 341                 return 0;
 342         }
 343
 344         acl_tdb_delete(handle, db, &fsp->fsp_name->st);
 345         return 0;
 346 }
 347
 348 static NTSTATUS acl_tdb_fget_nt_acl(vfs_handle_struct *handle,
 349                                     files_struct *fsp,
 350                                     uint32_t security_info,
 351                                     TALLOC_CTX *mem_ctx,
 352                                     struct security_descriptor **ppdesc)
 353 {
 354         NTSTATUS status;
 355         status = fget_nt_acl_common(fget_acl_blob, handle, fsp,
 356                                    security_info, mem_ctx, ppdesc);
 357         return status;
 358 }
 359
 360 static NTSTATUS acl_tdb_fset_nt_acl(vfs_handle_struct *handle,
 361                                     files_struct *fsp,
 362                                     uint32_t security_info_sent,
 363                                     const struct security_descriptor *psd)
 364 {
 365         NTSTATUS status;
 366         status = fset_nt_acl_common(fget_acl_blob, store_acl_blob_fsp,
 367                                     ACL_MODULE_NAME,
 368                                     handle, fsp, security_info_sent, psd);
 369         return status;
 370 }
 371
 372 static struct vfs_fn_pointers vfs_acl_tdb_fns = {
 373         .connect_fn = connect_acl_tdb,
 374         .disconnect_fn = disconnect_acl_tdb,
 375         .unlinkat_fn = unlinkat_acl_tdb,
 376         .fchmod_fn = fchmod_acl_module_common,
 377         .fget_nt_acl_fn = acl_tdb_fget_nt_acl,
 378         .fset_nt_acl_fn = acl_tdb_fset_nt_acl,
 379         .sys_acl_set_fd_fn = sys_acl_set_fd_tdb
 380 };
 381
 382 static_decl_vfs;
 383 NTSTATUS vfs_acl_tdb_init(TALLOC_CTX *ctx)
 384 {
 385         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
 386                                 &vfs_acl_tdb_fns);
 387 }