static void set_startloc( rtems_filesystem_eval_path_context_t *ctx, rtems_filesystem_global_location_t *const *global_root_ptr, rtems_filesystem_global_location_t *const *global_current_ptr ) { if (ctx->pathlen > 0) { char c = ctx->path [0]; ctx->rootloc = rtems_filesystem_global_location_obtain(global_root_ptr); if (rtems_filesystem_is_delimiter(c)) { ++ctx->path; --ctx->pathlen; ctx->startloc = rtems_filesystem_global_location_obtain( &ctx->rootloc ); } else { ctx->startloc = rtems_filesystem_global_location_obtain( global_current_ptr ); } } else { ctx->rootloc = rtems_filesystem_global_location_obtain_null(); ctx->startloc = rtems_filesystem_global_location_obtain_null(); errno = ENOENT; } }
void rtems_filesystem_eval_path_restart( rtems_filesystem_eval_path_context_t *ctx, rtems_filesystem_global_location_t **newstartloc_ptr ) { free_location(&ctx->currentloc); rtems_filesystem_instance_unlock(&ctx->startloc->location); rtems_filesystem_global_location_assign( &ctx->startloc, rtems_filesystem_global_location_obtain(newstartloc_ptr) ); rtems_filesystem_instance_lock(&ctx->startloc->location); rtems_filesystem_location_clone(&ctx->currentloc, &ctx->startloc->location); }
static int register_root_file_system( rtems_filesystem_mount_table_entry_t *mt_entry ) { int rv = 0; rtems_filesystem_mt_lock(); if ( rtems_chain_is_empty( &rtems_filesystem_mount_table ) ) { rtems_chain_append_unprotected( &rtems_filesystem_mount_table, &mt_entry->mt_node ); } else { errno = EINVAL; rv = -1; } rtems_filesystem_mt_unlock(); if ( rv == 0 ) { rtems_filesystem_global_location_t *new_fs_root = rtems_filesystem_global_location_obtain( &mt_entry->mt_fs_root ); rtems_filesystem_global_location_t *new_fs_current = rtems_filesystem_global_location_obtain( &mt_entry->mt_fs_root ); rtems_filesystem_global_location_assign( &rtems_filesystem_root, new_fs_root ); rtems_filesystem_global_location_assign( &rtems_filesystem_current, new_fs_current ); } return rv; }
int chroot( const char *path ) { int rv = 0; rtems_status_code sc = RTEMS_SUCCESSFUL; rtems_filesystem_eval_path_context_t ctx; int eval_flags = RTEMS_FS_PERMS_EXEC | RTEMS_FS_FOLLOW_LINK; rtems_filesystem_location_info_t loc; rtems_filesystem_global_location_t *new_current_loc; /* * We use the global environment for path evaluation. This makes it possible * to escape from a chroot environment referencing an unmounted file system. */ rtems_filesystem_eval_path_start_with_root_and_current( &ctx, path, eval_flags, &rtems_global_user_env.root_directory, &rtems_global_user_env.current_directory ); rtems_filesystem_eval_path_extract_currentloc( &ctx, &loc ); new_current_loc = rtems_filesystem_location_transform_to_global( &loc ); if ( !rtems_filesystem_global_location_is_null( new_current_loc ) ) { rtems_filesystem_global_location_t *new_root_loc = rtems_filesystem_global_location_obtain( &new_current_loc ); rtems_filesystem_node_types_t type = (*new_root_loc->location.mt_entry->ops->node_type_h)( &new_root_loc->location ); if ( type == RTEMS_FILESYSTEM_DIRECTORY ) { sc = rtems_libio_set_private_env(); if (sc == RTEMS_SUCCESSFUL) { rtems_filesystem_global_location_assign( &rtems_filesystem_root, new_root_loc ); rtems_filesystem_global_location_assign( &rtems_filesystem_current, new_current_loc ); } else { if (sc != RTEMS_UNSATISFIED) { errno = ENOMEM; } rv = -1; } } else { rtems_filesystem_location_error( &new_root_loc->location, ENOTDIR ); rv = -1; } if ( rv != 0 ) { rtems_filesystem_global_location_release( new_root_loc ); } } else { rv = -1; } rtems_filesystem_eval_path_cleanup( &ctx ); if ( rv != 0 ) { rtems_filesystem_global_location_release( new_current_loc ); } return rv; }