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 #include "util_tdb.h"
  32
  33 #undef DBGC_CLASS
  34 #define DBGC_CLASS DBGC_VFS
  35
  36 #define ACL_MODULE_NAME "acl_tdb"
  37 #include "modules/vfs_acl_common.c"
  38
  39 static unsigned int ref_count;
  40 static struct db_context *acl_db;
  41
  42 /*******************************************************************
  43  Open acl_db if not already open, increment ref count.
  44 *******************************************************************/
  45
  46 static bool acl_tdb_init(void)
  47 {
  48         char *dbname;
  49
  50         if (acl_db) {
  51                 ref_count++;
  52                 return true;
  53         }
  54
  55         dbname = state_path("file_ntacls.tdb");
  56
  57         if (dbname == NULL) {
  58                 errno = ENOSYS;
  59                 return false;
  60         }
  61
  62         become_root();
  63         acl_db = db_open(NULL, dbname, 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600);
  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 id_buf[16];
 103
 104         /* For backwards compatibility only store the dev/inode. */
 105         push_file_id_16((char *)id_buf, id);
 106         return db->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 = rec->delete_rec(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 char *name,
 147                         DATA_BLOB *pblob)
 148 {
 149         uint8 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_fname(handle->conn, name, &sbuf);
 163                 if (ret == -1) {
 164                         status = map_nt_error_from_unix(errno);
 165                 }
 166         }
 167
 168         if (!NT_STATUS_IS_OK(status)) {
 169                 return status;
 170         }
 171
 172         id = vfs_file_id_from_sbuf(handle->conn, &sbuf);
 173
 174         /* For backwards compatibility only store the dev/inode. */
 175         push_file_id_16((char *)id_buf, &id);
 176
 177         if (db->fetch(db,
 178                         ctx,
 179                         make_tdb_data(id_buf, sizeof(id_buf)),
 180                         &data) != 0) {
 181                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 182         }
 183
 184         pblob->data = data.dptr;
 185         pblob->length = data.dsize;
 186
 187         DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
 188                 (unsigned int)data.dsize, name ));
 189
 190         if (pblob->length == 0 || pblob->data == NULL) {
 191                 return NT_STATUS_NOT_FOUND;
 192         }
 193         return NT_STATUS_OK;
 194 }
 195
 196 /*******************************************************************
 197  Store a DATA_BLOB into a tdb record given an fsp pointer.
 198 *******************************************************************/
 199
 200 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
 201                                 files_struct *fsp,
 202                                 DATA_BLOB *pblob)
 203 {
 204         uint8 id_buf[16];
 205         struct file_id id;
 206         TDB_DATA data;
 207         struct db_context *db = acl_db;
 208         struct db_record *rec;
 209         NTSTATUS status;
 210
 211         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
 212                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
 213
 214         status = vfs_stat_fsp(fsp);
 215         if (!NT_STATUS_IS_OK(status)) {
 216                 return status;
 217         }
 218
 219         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 220
 221         /* For backwards compatibility only store the dev/inode. */
 222         push_file_id_16((char *)id_buf, &id);
 223         rec = db->fetch_locked(db, talloc_tos(),
 224                                 make_tdb_data(id_buf,
 225                                         sizeof(id_buf)));
 226         if (rec == NULL) {
 227                 DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
 228                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 229         }
 230         data.dptr = pblob->data;
 231         data.dsize = pblob->length;
 232         return rec->store(rec, data, 0);
 233 }
 234
 235 /*********************************************************************
 236  On unlink we need to delete the tdb record (if using tdb).
 237 *********************************************************************/
 238
 239 static int unlink_acl_tdb(vfs_handle_struct *handle,
 240                           const struct smb_filename *smb_fname)
 241 {
 242         struct smb_filename *smb_fname_tmp = NULL;
 243         struct db_context *db = acl_db;
 244         NTSTATUS status;
 245         int ret = -1;
 246
 247         status = copy_smb_filename(talloc_tos(), smb_fname, &smb_fname_tmp);
 248         if (!NT_STATUS_IS_OK(status)) {
 249                 errno = map_errno_from_nt_status(status);
 250                 goto out;
 251         }
 252
 253         if (lp_posix_pathnames()) {
 254                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
 255         } else {
 256                 ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
 257         }
 258
 259         if (ret == -1) {
 260                 goto out;
 261         }
 262
 263         ret = unlink_acl_common(handle, smb_fname_tmp);
 264
 265         if (ret == -1) {
 266                 goto out;
 267         }
 268
 269         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 270  out:
 271         return ret;
 272 }
 273
 274 /*********************************************************************
 275  On rmdir we need to delete the tdb record (if using tdb).
 276 *********************************************************************/
 277
 278 static int rmdir_acl_tdb(vfs_handle_struct *handle, const char *path)
 279 {
 280
 281         SMB_STRUCT_STAT sbuf;
 282         struct db_context *db = acl_db;
 283         int ret = -1;
 284
 285         if (lp_posix_pathnames()) {
 286                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 287         } else {
 288                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 289         }
 290
 291         if (ret == -1) {
 292                 return -1;
 293         }
 294
 295         ret = rmdir_acl_common(handle, path);
 296         if (ret == -1) {
 297                 return -1;
 298         }
 299
 300         acl_tdb_delete(handle, db, &sbuf);
 301         return 0;
 302 }
 303
 304 /*******************************************************************
 305  Handle opening the storage tdb if so configured.
 306 *******************************************************************/
 307
 308 static int connect_acl_tdb(struct vfs_handle_struct *handle,
 309                                 const char *service,
 310                                 const char *user)
 311 {
 312         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
 313
 314         if (ret < 0) {
 315                 return ret;
 316         }
 317
 318         if (!acl_tdb_init()) {
 319                 SMB_VFS_NEXT_DISCONNECT(handle);
 320                 return -1;
 321         }
 322
 323         /* Ensure we have the parameters correct if we're
 324          * using this module. */
 325         DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
 326                 "'dos filemode = true' and "
 327                 "'force unknown acl user = true' for service %s\n",
 328                 service ));
 329
 330         lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
 331         lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");
 332         lp_do_parameter(SNUM(handle->conn), "force unknown acl user", "true");
 333
 334         return 0;
 335 }
 336
 337 /*********************************************************************
 338  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 339 *********************************************************************/
 340
 341 static int sys_acl_set_file_tdb(vfs_handle_struct *handle,
 342                               const char *path,
 343                               SMB_ACL_TYPE_T type,
 344                               SMB_ACL_T theacl)
 345 {
 346         SMB_STRUCT_STAT sbuf;
 347         struct db_context *db = acl_db;
 348         int ret = -1;
 349
 350         if (lp_posix_pathnames()) {
 351                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 352         } else {
 353                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 354         }
 355
 356         if (ret == -1) {
 357                 return -1;
 358         }
 359
 360         ret = SMB_VFS_NEXT_SYS_ACL_SET_FILE(handle,
 361                                                 path,
 362                                                 type,
 363                                                 theacl);
 364         if (ret == -1) {
 365                 return -1;
 366         }
 367
 368         acl_tdb_delete(handle, db, &sbuf);
 369         return 0;
 370 }
 371
 372 /*********************************************************************
 373  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 374 *********************************************************************/
 375
 376 static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
 377                             files_struct *fsp,
 378                             SMB_ACL_T theacl)
 379 {
 380         struct db_context *db = acl_db;
 381         NTSTATUS status;
 382         int ret;
 383
 384         status = vfs_stat_fsp(fsp);
 385         if (!NT_STATUS_IS_OK(status)) {
 386                 return -1;
 387         }
 388
 389         ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
 390                                                 fsp,
 391                                                 theacl);
 392         if (ret == -1) {
 393                 return -1;
 394         }
 395
 396         acl_tdb_delete(handle, db, &fsp->fsp_name->st);
 397         return 0;
 398 }
 399
 400 static struct vfs_fn_pointers vfs_acl_tdb_fns = {
 401         .connect_fn = connect_acl_tdb,
 402         .disconnect = disconnect_acl_tdb,
 403         .opendir = opendir_acl_common,
 404         .mkdir = mkdir_acl_common,
 405         .rmdir = rmdir_acl_tdb,
 406         .open_fn = open_acl_common,
 407         .create_file = create_file_acl_common,
 408         .unlink = unlink_acl_tdb,
 409         .chmod = chmod_acl_module_common,
 410         .fchmod = fchmod_acl_module_common,
 411         .fget_nt_acl = fget_nt_acl_common,
 412         .get_nt_acl = get_nt_acl_common,
 413         .fset_nt_acl = fset_nt_acl_common,
 414         .chmod_acl = chmod_acl_acl_module_common,
 415         .fchmod_acl = fchmod_acl_acl_module_common,
 416         .sys_acl_set_file = sys_acl_set_file_tdb,
 417         .sys_acl_set_fd = sys_acl_set_fd_tdb
 418 };
 419
 420 NTSTATUS vfs_acl_tdb_init(void)
 421 {
 422         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
 423                                 &vfs_acl_tdb_fns);
 424 }