# -*- coding: utf-8 -*-
"""This file contains the Debian dpkg.log file parser.
Information updated 02 September 2016.
An example:
2016-08-03 15:25:53 install base-passwd:amd64 <none> 3.5.33
Log messages are of the form:
YYYY-MM-DD HH:MM:SS startup type command
Where type is:
archives (with a command of unpack or install)
packages (with a command of configure, triggers-only, remove or purge)
YYYY-MM-DD HH:MM:SS status state pkg installed-version
YYYY-MM-DD HH:MM:SS action pkg installed-version available-version
Where action is:
install, upgrade, configure, trigproc, disappear, remove or purge.
YYYY-MM-DD HH:MM:SS conffile filename decision
Where decision is install or keep.
"""
from __future__ import unicode_literals
import pyparsing
from dfdatetime import time_elements as dfdatetime_time_elements
from plaso.containers import events
from plaso.containers import time_events
from plaso.lib import errors
from plaso.lib import definitions
from plaso.parsers import logger
from plaso.parsers import manager
from plaso.parsers import text_parser
[docs]class DpkgEventData(events.EventData):
"""Dpkg event data.
Attributes:
body (str): body of the log line.
"""
DATA_TYPE = 'dpkg:line'
def __init__(self):
"""Initializes event data."""
super(DpkgEventData, self).__init__(data_type=self.DATA_TYPE)
self.body = None
[docs]class DpkgParser(text_parser.PyparsingSingleLineTextParser):
"""Parser for Debian dpkg.log files."""
NAME = 'dpkg'
DESCRIPTION = 'Parser for Debian dpkg.log files.'
_ENCODING = 'utf-8'
_DPKG_STARTUP = 'startup'
_DPKG_STATUS = 'status'
_DPKG_CONFFILE = 'conffile'
_DPKG_ACTIONS = [
'install',
'upgrade',
'configure',
'trigproc',
'disappear',
'remove',
'purge']
_DPKG_STARTUP_TYPES = [
'archives',
'packages']
_DPKG_STARTUP_COMMANDS = [
'unpack',
'install',
'configure',
'triggers-only',
'remove',
'purge']
_DPKG_CONFFILE_DECISIONS = [
'install',
'keep']
_DPKG_STARTUP_BODY = pyparsing.Combine(
pyparsing.Literal(_DPKG_STARTUP) +
pyparsing.oneOf(_DPKG_STARTUP_TYPES) +
pyparsing.oneOf(_DPKG_STARTUP_COMMANDS),
joinString=' ', adjacent=False)
_DPKG_STATUS_BODY = pyparsing.Combine(
pyparsing.Literal(_DPKG_STATUS) +
pyparsing.Word(pyparsing.printables) +
pyparsing.Word(pyparsing.printables) +
pyparsing.Word(pyparsing.printables),
joinString=' ', adjacent=False)
_DPKG_ACTION_BODY = pyparsing.Combine(
pyparsing.oneOf(_DPKG_ACTIONS) +
pyparsing.Word(pyparsing.printables) +
pyparsing.Word(pyparsing.printables) +
pyparsing.Word(pyparsing.printables),
joinString=' ', adjacent=False)
_DPKG_CONFFILE_BODY = pyparsing.Combine(
pyparsing.Literal(_DPKG_CONFFILE) +
pyparsing.Word(pyparsing.printables) +
pyparsing.oneOf(_DPKG_CONFFILE_DECISIONS),
joinString=' ', adjacent=False)
_DPKG_LOG_LINE = (
text_parser.PyparsingConstants.DATE_TIME.setResultsName('date_time') +
pyparsing.MatchFirst([
_DPKG_STARTUP_BODY,
_DPKG_STATUS_BODY,
_DPKG_ACTION_BODY,
_DPKG_CONFFILE_BODY]).setResultsName('body'))
LINE_STRUCTURES = [('line', _DPKG_LOG_LINE)]
[docs] def ParseRecord(self, parser_mediator, key, structure):
"""Parses a structure of tokens derived from a line of a text file.
Args:
parser_mediator (ParserMediator): parser mediator.
key (str): identifier of the structure of tokens.
structure (pyparsing.ParseResults): structure of tokens derived from
a line of a text file.
Raises:
ParseError: when the structure type is unknown.
"""
if key != 'line':
raise errors.ParseError(
'Unable to parse record, unknown structure: {0:s}'.format(key))
time_elements_tuple = self._GetValueFromStructure(structure, 'date_time')
try:
date_time = dfdatetime_time_elements.TimeElements(
time_elements_tuple=time_elements_tuple)
except ValueError:
parser_mediator.ProduceExtractionWarning(
'invalid date time value: {0!s}'.format(time_elements_tuple))
return
body_text = self._GetValueFromStructure(structure, 'body')
if not body_text:
parser_mediator.ProduceExtractionWarning('missing body text')
return
event_data = DpkgEventData()
event_data.body = body_text
event = time_events.DateTimeValuesEvent(
date_time, definitions.TIME_DESCRIPTION_ADDED)
parser_mediator.ProduceEventWithEventData(event, event_data)
[docs] def VerifyStructure(self, parser_mediator, line):
"""Verifies if a line from a text file is in the expected format.
Args:
parser_mediator (ParserMediator): parser mediator.
line (str): line from a text file.
Returns:
bool: True if the line is in the expected format, False if not.
"""
try:
structure = self._DPKG_LOG_LINE.parseString(line)
except pyparsing.ParseException as exception:
logger.debug(
'Unable to parse Debian dpkg.log file with error: {0!s}'.format(
exception))
return False
return 'date_time' in structure and 'body' in structure
manager.ParsersManager.RegisterParser(DpkgParser)