plaso-rubanetra/plaso/parsers/filestat.py
2020-04-06 18:48:34 +02:00

130 lines
4.3 KiB
Python

#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Copyright 2012 The Plaso Project Authors.
# Please see the AUTHORS file for details on individual authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""File system stat object parser."""
from dfvfs.lib import definitions as dfvfs_definitions
from plaso.events import time_events
from plaso.lib import timelib
from plaso.parsers import interface
from plaso.parsers import manager
class FileStatEvent(time_events.TimestampEvent):
"""File system stat event."""
DATA_TYPE = 'fs:stat'
def __init__(self, timestamp, usage, allocated, size, fs_type):
"""Initializes the event.
Args:
timestamp: The timestamp value.
usage: The usage string describing the timestamp.
allocated: Boolean value to indicate the file entry is allocated.
size: The file size in bytes.
fs_type: The filesystem this timestamp is extracted from.
"""
super(FileStatEvent, self).__init__(timestamp, usage)
self.offset = 0
self.size = size
self.allocated = allocated
self.fs_type = fs_type
class FileStatParser(interface.BaseParser):
"""Class that defines a file system stat object parser."""
NAME = 'filestat'
DESCRIPTION = u'Parser for file system stat information.'
_TIME_ATTRIBUTES = frozenset([
'atime', 'bkup_time', 'ctime', 'crtime', 'dtime', 'mtime'])
def _GetFileSystemTypeFromFileEntry(self, file_entry):
"""Return a filesystem type string from a file entry object.
Args:
file_entry: A file entry object (instance of vfs.file_entry.FileEntry).
Returns:
A string indicating the file system type.
"""
file_system = file_entry.GetFileSystem()
type_indicator = file_system.type_indicator
if type_indicator != dfvfs_definitions.TYPE_INDICATOR_TSK:
return type_indicator
# TODO: Implement fs_type in dfVFS and remove this implementation
# once that is in place.
fs_info = file_system.GetFsInfo()
if fs_info.info:
type_string = unicode(fs_info.info.ftype)
if type_string.startswith('TSK_FS_TYPE'):
return type_string[12:]
def Parse(self, parser_context, file_entry, parser_chain=None):
"""Extracts event objects from a file system stat entry.
Args:
parser_context: A parser context object (instance of ParserContext).
file_entry: A file entry object (instance of dfvfs.FileEntry).
parser_chain: Optional string containing the parsing chain up to this
point. The default is None.
"""
stat_object = file_entry.GetStat()
if not stat_object:
return
# Add ourselves to the parser chain, which will be used in all subsequent
# event creation in this parser.
parser_chain = self._BuildParserChain(parser_chain)
file_system_type = self._GetFileSystemTypeFromFileEntry(file_entry)
is_allocated = getattr(stat_object, 'allocated', True)
file_size = getattr(stat_object, 'size', None),
for time_attribute in self._TIME_ATTRIBUTES:
timestamp = getattr(stat_object, time_attribute, None)
if timestamp is None:
continue
nano_time_attribute = u'{0:s}_nano'.format(time_attribute)
nano_time_attribute = getattr(stat_object, nano_time_attribute, None)
timestamp = timelib.Timestamp.FromPosixTime(timestamp)
if nano_time_attribute is not None:
# Note that the _nano values are in intervals of 100th nano seconds.
timestamp += nano_time_attribute / 10
# TODO: this also ignores any timestamp that equals 0.
# Is this the desired behavior?
if not timestamp:
continue
event_object = FileStatEvent(
timestamp, time_attribute, is_allocated, file_size, file_system_type)
parser_context.ProduceEvent(
event_object, parser_chain=parser_chain, file_entry=file_entry)
manager.ParsersManager.RegisterParser(FileStatParser)