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 "system/filesys.h"
  25 #include "librpc/gen_ndr/xattr.h"
  26 #include "librpc/gen_ndr/ndr_xattr.h"
  27 #include "../lib/crypto/crypto.h"
  28 #include "dbwrap.h"
  29
  30 #undef DBGC_CLASS
  31 #define DBGC_CLASS DBGC_VFS
  32
  33 #define ACL_MODULE_NAME "acl_tdb"
  34 #include "modules/vfs_acl_common.c"
  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("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         unbecome_root();
  62
  63         if (acl_db == NULL) {
  64 #if defined(ENOTSUP)
  65                 errno = ENOTSUP;
  66 #else
  67                 errno = ENOSYS;
  68 #endif
  69                 TALLOC_FREE(dbname);
  70                 return false;
  71         }
  72
  73         ref_count++;
  74         TALLOC_FREE(dbname);
  75         return true;
  76 }
  77
  78 /*******************************************************************
  79  Lower ref count and close acl_db if zero.
  80 *******************************************************************/
  81
  82 static void disconnect_acl_tdb(struct vfs_handle_struct *handle)
  83 {
  84         SMB_VFS_NEXT_DISCONNECT(handle);
  85         ref_count--;
  86         if (ref_count == 0) {
  87                 TALLOC_FREE(acl_db);
  88         }
  89 }
  90
  91 /*******************************************************************
  92  Fetch_lock the tdb acl record for a file
  93 *******************************************************************/
  94
  95 static struct db_record *acl_tdb_lock(TALLOC_CTX *mem_ctx,
  96                                         struct db_context *db,
  97                                         const struct file_id *id)
  98 {
  99         uint8 id_buf[16];
 100
 101         /* For backwards compatibility only store the dev/inode. */
 102         push_file_id_16((char *)id_buf, id);
 103         return db->fetch_locked(db,
 104                                 mem_ctx,
 105                                 make_tdb_data(id_buf,
 106                                         sizeof(id_buf)));
 107 }
 108
 109 /*******************************************************************
 110  Delete the tdb acl record for a file
 111 *******************************************************************/
 112
 113 static NTSTATUS acl_tdb_delete(vfs_handle_struct *handle,
 114                                 struct db_context *db,
 115                                 SMB_STRUCT_STAT *psbuf)
 116 {
 117         NTSTATUS status;
 118         struct file_id id = vfs_file_id_from_sbuf(handle->conn, psbuf);
 119         struct db_record *rec = acl_tdb_lock(talloc_tos(), db, &id);
 120
 121         /*
 122          * If rec == NULL there's not much we can do about it
 123          */
 124
 125         if (rec == NULL) {
 126                 DEBUG(10,("acl_tdb_delete: rec == NULL\n"));
 127                 TALLOC_FREE(rec);
 128                 return NT_STATUS_OK;
 129         }
 130
 131         status = rec->delete_rec(rec);
 132         TALLOC_FREE(rec);
 133         return status;
 134 }
 135
 136 /*******************************************************************
 137  Pull a security descriptor into a DATA_BLOB from a tdb store.
 138 *******************************************************************/
 139
 140 static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
 141                         vfs_handle_struct *handle,
 142                         files_struct *fsp,
 143                         const char *name,
 144                         DATA_BLOB *pblob)
 145 {
 146         uint8 id_buf[16];
 147         TDB_DATA data;
 148         struct file_id id;
 149         struct db_context *db = acl_db;
 150         NTSTATUS status = NT_STATUS_OK;
 151         SMB_STRUCT_STAT sbuf;
 152
 153         ZERO_STRUCT(sbuf);
 154
 155         if (fsp) {
 156                 status = vfs_stat_fsp(fsp);
 157                 sbuf = fsp->fsp_name->st;
 158         } else {
 159                 int ret = vfs_stat_smb_fname(handle->conn, name, &sbuf);
 160                 if (ret == -1) {
 161                         status = map_nt_error_from_unix(errno);
 162                 }
 163         }
 164
 165         if (!NT_STATUS_IS_OK(status)) {
 166                 return status;
 167         }
 168
 169         id = vfs_file_id_from_sbuf(handle->conn, &sbuf);
 170
 171         /* For backwards compatibility only store the dev/inode. */
 172         push_file_id_16((char *)id_buf, &id);
 173
 174         if (db->fetch(db,
 175                         ctx,
 176                         make_tdb_data(id_buf, sizeof(id_buf)),
 177                         &data) == -1) {
 178                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 179         }
 180
 181         pblob->data = data.dptr;
 182         pblob->length = data.dsize;
 183
 184         DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
 185                 (unsigned int)data.dsize, name ));
 186
 187         if (pblob->length == 0 || pblob->data == NULL) {
 188                 return NT_STATUS_NOT_FOUND;
 189         }
 190         return NT_STATUS_OK;
 191 }
 192
 193 /*******************************************************************
 194  Store a DATA_BLOB into a tdb record given an fsp pointer.
 195 *******************************************************************/
 196
 197 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
 198                                 files_struct *fsp,
 199                                 DATA_BLOB *pblob)
 200 {
 201         uint8 id_buf[16];
 202         struct file_id id;
 203         TDB_DATA data;
 204         struct db_context *db = acl_db;
 205         struct db_record *rec;
 206         NTSTATUS status;
 207
 208         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
 209                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
 210
 211         status = vfs_stat_fsp(fsp);
 212         if (!NT_STATUS_IS_OK(status)) {
 213                 return status;
 214         }
 215
 216         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 217
 218         /* For backwards compatibility only store the dev/inode. */
 219         push_file_id_16((char *)id_buf, &id);
 220         rec = db->fetch_locked(db, talloc_tos(),
 221                                 make_tdb_data(id_buf,
 222                                         sizeof(id_buf)));
 223         if (rec == NULL) {
 224                 DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
 225                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 226         }
 227         data.dptr = pblob->data;
 228         data.dsize = pblob->length;
 229         return rec->store(rec, data, 0);
 230 }
 231
 232 /*********************************************************************
 233  On unlink we need to delete the tdb record (if using tdb).
 234 *********************************************************************/
 235
 236 static int unlink_acl_tdb(vfs_handle_struct *handle,
 237                           const struct smb_filename *smb_fname)
 238 {
 239         struct smb_filename *smb_fname_tmp = NULL;
 240         struct db_context *db = acl_db;
 241         NTSTATUS status;
 242         int ret = -1;
 243
 244         status = copy_smb_filename(talloc_tos(), smb_fname, &smb_fname_tmp);
 245         if (!NT_STATUS_IS_OK(status)) {
 246                 errno = map_errno_from_nt_status(status);
 247                 goto out;
 248         }
 249
 250         if (lp_posix_pathnames()) {
 251                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
 252         } else {
 253                 ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
 254         }
 255
 256         if (ret == -1) {
 257                 goto out;
 258         }
 259
 260         ret = unlink_acl_common(handle, smb_fname_tmp);
 261
 262         if (ret == -1) {
 263                 goto out;
 264         }
 265
 266         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 267  out:
 268         return ret;
 269 }
 270
 271 /*********************************************************************
 272  On rmdir we need to delete the tdb record (if using tdb).
 273 *********************************************************************/
 274
 275 static int rmdir_acl_tdb(vfs_handle_struct *handle, const char *path)
 276 {
 277
 278         SMB_STRUCT_STAT sbuf;
 279         struct db_context *db = acl_db;
 280         int ret = -1;
 281
 282         if (lp_posix_pathnames()) {
 283                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 284         } else {
 285                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 286         }
 287
 288         if (ret == -1) {
 289                 return -1;
 290         }
 291
 292         ret = rmdir_acl_common(handle, path);
 293         if (ret == -1) {
 294                 return -1;
 295         }
 296
 297         acl_tdb_delete(handle, db, &sbuf);
 298         return 0;
 299 }
 300
 301 /*******************************************************************
 302  Handle opening the storage tdb if so configured.
 303 *******************************************************************/
 304
 305 static int connect_acl_tdb(struct vfs_handle_struct *handle,
 306                                 const char *service,
 307                                 const char *user)
 308 {
 309         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
 310
 311         if (ret < 0) {
 312                 return ret;
 313         }
 314
 315         if (!acl_tdb_init()) {
 316                 SMB_VFS_NEXT_DISCONNECT(handle);
 317                 return -1;
 318         }
 319
 320         /* Ensure we have the parameters correct if we're
 321          * using this module. */
 322         DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
 323                 "'dos filemode = true' and "
 324                 "'force unknown acl user = true' for service %s\n",
 325                 service ));
 326
 327         lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
 328         lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");
 329         lp_do_parameter(SNUM(handle->conn), "force unknown acl user", "true");
 330
 331         return 0;
 332 }
 333
 334 /*********************************************************************
 335  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 336 *********************************************************************/
 337
 338 static int sys_acl_set_file_tdb(vfs_handle_struct *handle,
 339                               const char *path,
 340                               SMB_ACL_TYPE_T type,
 341                               SMB_ACL_T theacl)
 342 {
 343         SMB_STRUCT_STAT sbuf;
 344         struct db_context *db = acl_db;
 345         int ret = -1;
 346
 347         if (lp_posix_pathnames()) {
 348                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 349         } else {
 350                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 351         }
 352
 353         if (ret == -1) {
 354                 return -1;
 355         }
 356
 357         ret = SMB_VFS_NEXT_SYS_ACL_SET_FILE(handle,
 358                                                 path,
 359                                                 type,
 360                                                 theacl);
 361         if (ret == -1) {
 362                 return -1;
 363         }
 364
 365         acl_tdb_delete(handle, db, &sbuf);
 366         return 0;
 367 }
 368
 369 /*********************************************************************
 370  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 371 *********************************************************************/
 372
 373 static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
 374                             files_struct *fsp,
 375                             SMB_ACL_T theacl)
 376 {
 377         struct db_context *db = acl_db;
 378         NTSTATUS status;
 379         int ret;
 380
 381         status = vfs_stat_fsp(fsp);
 382         if (!NT_STATUS_IS_OK(status)) {
 383                 return -1;
 384         }
 385
 386         ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
 387                                                 fsp,
 388                                                 theacl);
 389         if (ret == -1) {
 390                 return -1;
 391         }
 392
 393         acl_tdb_delete(handle, db, &fsp->fsp_name->st);
 394         return 0;
 395 }
 396
 397 static struct vfs_fn_pointers vfs_acl_tdb_fns = {
 398         .connect_fn = connect_acl_tdb,
 399         .disconnect = disconnect_acl_tdb,
 400         .opendir = opendir_acl_common,
 401         .mkdir = mkdir_acl_common,
 402         .open = open_acl_common,
 403         .create_file = create_file_acl_common,
 404         .unlink = unlink_acl_tdb,
 405         .rmdir = rmdir_acl_tdb,
 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         .sys_acl_set_file = sys_acl_set_file_tdb,
 410         .sys_acl_set_fd = sys_acl_set_fd_tdb
 411 };
 412
 413 NTSTATUS vfs_acl_tdb_init(void)
 414 {
 415         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
 416                                 &vfs_acl_tdb_fns);
 417 }