Source code for plaso.engine.tagging_file

# -*- coding: utf-8 -*-
"""Tagging file."""

from __future__ import unicode_literals

import io
import re

from plaso.filters import event_filter
from plaso.lib import errors


[docs]class TaggingFile(object): """Tagging file that defines one or more event tagging rules.""" # A line with no indent is a tag name. _TAG_LABEL_LINE = re.compile(r'^(\w+)') # A line with leading indent is one of the rules for the preceding tag. _TAG_RULE_LINE = re.compile(r'^\s+(.+)') # If any of these words are in the query then it's probably objectfilter. _OBJECTFILTER_WORDS = re.compile( r'\s(is|isnot|equals|notequals|inset|notinset|contains|notcontains)\s') def __init__(self, path): """Initializes a tagging file. Args: path (str): path to a file that contains one or more event tagging rules. """ super(TaggingFile, self).__init__() self._path = path
[docs] def GetEventTaggingRules(self): """Retrieves the event tagging rules from the tagging file. Returns: dict[str, FilterObject]: tagging rules, that consists of one or more filter objects per label. Raises: TaggingFileError: if a filter expression cannot be compiled. """ rules_per_label = {} label_name = None with io.open(self._path, 'r', encoding='utf-8') as tagging_file: for line in tagging_file.readlines(): line = line.rstrip() stripped_line = line.lstrip() if not stripped_line: label_name = None continue if stripped_line[0] == '#': continue if not line[0].isspace(): label_name = line rules_per_label[label_name] = [] elif label_name: rules_per_label[label_name].append(stripped_line) filter_objects_per_label = {} for label_name, rules in rules_per_label.items(): filter_object = event_filter.EventObjectFilter() try: filter_rule = ' OR '.join(['({0:s})'.format(rule) for rule in rules]) filter_object.CompileFilter(filter_rule) except errors.ParseError as exception: raise errors.TaggingFileError(( 'Unable to compile filter for label: {0:s} with error: ' '{1!s}').format(label_name, exception)) # TODO: change other code remove list around filter_object filter_objects_per_label[label_name] = [filter_object] return filter_objects_per_label