# -*_ coding: utf-8 -*-
"""Text parser plugin for System Center Configuration Manager (SCCM) logs."""
import re
from dfdatetime import time_elements as dfdatetime_time_elements
import pyparsing
from plaso.containers import events
from plaso.lib import errors
from plaso.parsers import text_parser
from plaso.parsers.text_plugins import interface
[docs]
class SCCMLogEventData(events.EventData):
"""SCCM log event data.
Attributes:
component (str): component.
text (str): text.
written_time (dfdatetime.DateTimeValues): date and time the entry was
written.
"""
DATA_TYPE = 'sccm_log:entry'
[docs]
def __init__(self):
"""Initializes event data."""
super(SCCMLogEventData, self).__init__(data_type=self.DATA_TYPE)
self.component = None
self.text = None
self.written_time = None
[docs]
class SCCMTextPlugin(interface.TextPlugin):
"""Text parser plugin for System Center Configuration Manager (SCCM) logs."""
NAME = 'sccm'
DATA_FORMAT = 'System Center Configuration Manager (SCCM) client log file'
ENCODING = 'utf-8'
_ONE_OR_TWO_DIGITS = pyparsing.Word(pyparsing.nums, max=2).set_parse_action(
lambda tokens: int(tokens[0], 10))
_TWO_OR_THREE_DIGITS = pyparsing.Word(
pyparsing.nums, min=2, max=3).set_parse_action(
lambda tokens: int(tokens[0], 10))
_TWO_DIGITS = pyparsing.Word(pyparsing.nums, exact=2).set_parse_action(
lambda tokens: int(tokens[0], 10))
_FOUR_DIGITS = pyparsing.Word(pyparsing.nums, exact=4).set_parse_action(
lambda tokens: int(tokens[0], 10))
# Date formatted as: date="M-D-YYYY"
_DATE = (pyparsing.Suppress('" date="') + _ONE_OR_TWO_DIGITS +
pyparsing.Suppress('-') + _ONE_OR_TWO_DIGITS +
pyparsing.Suppress('-') + _FOUR_DIGITS)
_TIME_ZONE_OFFSET = pyparsing.Group(
pyparsing.Word('+-', exact=1) + _TWO_OR_THREE_DIGITS)
# Time formatted as: time="h:mm:ss.###or time="h:mm:ss.###[+-]##"
_TIME = (pyparsing.Suppress('time="') + _ONE_OR_TWO_DIGITS +
pyparsing.Suppress(':') + _TWO_DIGITS + pyparsing.Suppress(':') +
_TWO_DIGITS + pyparsing.Suppress('.') + pyparsing.Regex(r'\d{3,7}') +
pyparsing.Optional(_TIME_ZONE_OFFSET))
_DATE_TIME = (_TIME + _DATE).set_results_name('date_time')
_LOG_MESSAGE_START = pyparsing.Suppress('<![LOG[')
# Using a regular expression look ahead here is faster than pyparsing.SkipTo()
_LOG_MESSAGE_TEXT = pyparsing.Regex(r'.*?(?=(]LOG]!><))', re.DOTALL)
_LOG_MESSAGE_END = pyparsing.Suppress(']LOG]!><')
_LOG_MESSAGE = (
_LOG_MESSAGE_START + _LOG_MESSAGE_TEXT.set_results_name('text') +
_LOG_MESSAGE_END)
_COMPONENT = (
pyparsing.Suppress('" component="') +
pyparsing.Word(pyparsing.alphanums).set_results_name('component'))
_END_OF_LINE = pyparsing.Suppress(pyparsing.LineEnd())
_LOG_LINE = (
_LOG_MESSAGE + _DATE_TIME + _COMPONENT +
pyparsing.Regex(r'.*?(?=(<!\[LOG\[))', re.DOTALL))
_LAST_LOG_LINE = (
_LOG_MESSAGE + _DATE_TIME + _COMPONENT +
pyparsing.restOfLine() + _END_OF_LINE)
_LINE_STRUCTURES = [
('log_line', _LOG_LINE),
('last_log_line', _LAST_LOG_LINE)]
# Because logs files can lead with a partial event, we can't assume that
# the first character (post-BOM) in the file is the beginning of our match,
# so we look for match anywhere in lines.
VERIFICATION_GRAMMAR = (
pyparsing.Regex(r'.*<!\[LOG\[.*]LOG]!><', re.DOTALL) + _DATE_TIME +
_COMPONENT)
VERIFICATION_LITERALS = ['<![LOG[', ']LOG]!><time="']
def _ParseRecord(self, parser_mediator, key, structure):
"""Parses a pyparsing structure.
Args:
parser_mediator (ParserMediator): mediates interactions between parsers
and other components, such as storage and dfVFS.
key (str): name of the parsed structure.
structure (pyparsing.ParseResults): tokens from a parsed log line.
Raises:
ParseError: if the structure cannot be parsed.
"""
time_elements_structure = self._GetValueFromStructure(
structure, 'date_time')
event_data = SCCMLogEventData()
event_data.component = self._GetValueFromStructure(structure, 'component')
event_data.text = self._GetValueFromStructure(structure, 'text')
event_data.written_time = self._ParseTimeElements(time_elements_structure)
parser_mediator.ProduceEventData(event_data)
def _ParseTimeElements(self, time_elements_structure):
"""Parses date and time elements of a log line.
Args:
time_elements_structure (pyparsing.ParseResults): date and time elements
of a log line.
Returns:
dfdatetime.TimeElements: date and time value.
Raises:
ParseError: if a valid date and time value cannot be derived from
the time elements.
"""
# Ensure time_elements_tuple is not a pyparsing.ParseResults otherwise
# copy.deepcopy() of the dfDateTime object will fail on Python 3.8 with:
# "TypeError: 'str' object is not callable" due to pyparsing.ParseResults
# overriding __getattr__ with a function that returns an empty string when
# named token does not exist.
try:
if len(time_elements_structure) == 8:
(hours, minutes, seconds, fraction_of_second, utc_offset_minutes, month,
day_of_month, year) = time_elements_structure
time_zone_offset = utc_offset_minutes[1]
if utc_offset_minutes[0] == '-':
time_zone_offset *= -1
else:
(hours, minutes, seconds, fraction_of_second, month, day_of_month,
year) = time_elements_structure
time_zone_offset = None
if len(fraction_of_second) == 3:
milliseconds = int(fraction_of_second, 10)
time_elements_tuple=(
year, month, day_of_month, hours, minutes, seconds, milliseconds)
date_time = dfdatetime_time_elements.TimeElementsInMilliseconds(
time_elements_tuple=time_elements_tuple,
time_zone_offset=time_zone_offset)
else:
# TODO: improve precision support, but for now ignore the 100ns
# precision.
microseconds = int(fraction_of_second[:6], 10)
time_elements_tuple=(
year, month, day_of_month, hours, minutes, seconds, microseconds)
date_time = dfdatetime_time_elements.TimeElementsInMicroseconds(
time_elements_tuple=time_elements_tuple,
time_zone_offset=time_zone_offset)
return date_time
except (TypeError, ValueError) as exception:
raise errors.ParseError(
'Unable to parse time elements with error: {0!s}'.format(exception))
[docs]
def CheckRequiredFormat(self, parser_mediator, text_reader):
"""Check if the log record has the minimal structure required by the parser.
Args:
parser_mediator (ParserMediator): mediates interactions between parsers
and other components, such as storage and dfVFS.
text_reader (EncodedTextReader): text reader.
Returns:
bool: True if this is the correct plugin, False otherwise.
"""
try:
structure = self._VerifyString(text_reader.lines)
except errors.ParseError:
return False
time_elements_structure = self._GetValueFromStructure(
structure, 'date_time')
try:
self._ParseTimeElements(time_elements_structure)
except errors.ParseError:
return False
return True
text_parser.TextLogParser.RegisterPlugin(SCCMTextPlugin)