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

276 lines
11 KiB
Python

#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Copyright 2014 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.
"""This file contains Popularity Contest log file parser in plaso.
Information updated 20 january 2014.
From Debian Package Popularity Contest
Avery Pennarun <apenwarr@debian.org>
From 'http://www.unix.com/man-page/Linux/8/popularity-contest/':
'
The popularity-contest command gathers information about Debian pack-
ages installed on the system, and prints the name of the most recently
used executable program in that package as well as its last-accessed
time (atime) and last-attribute-changed time (ctime) to stdout.
When aggregated with the output of popularity-contest from many other
systems, this information is valuable because it can be used to deter-
mine which Debian packages are commonly installed, used, or installed
and never used. This helps Debian maintainers make decisions such as
which packages should be installed by default on new systems.
The resulting statistic is available from the project home page
http://popcon.debian.org/.
Normally, popularity-contest is run from a cron(8) job,
/etc/cron.daily/popularity-contest, which automatically submits the
results to Debian package maintainers (only once a week) according to
the settings in /etc/popularity-contest.conf and /usr/share/popularity-
contest/default.conf.
'
From 'http://popcon.ubuntu.com/README':
'
The popularity-contest output looks like this:
POPULARITY-CONTEST-0 TIME:914183330 ID:b92a5fc1809d8a95a12eb3a3c8445
914183333 909868335 grep /bin/fgrep
914183333 909868280 findutils /usr/bin/find
914183330 909885698 dpkg-awk /usr/bin/dpkg-awk
914183330 909868577 gawk /usr/bin/gawk
[...more lines...]
END-POPULARITY-CONTEST-0 TIME:914183335
The first and last lines allow you to put more than one set of
popularity-contest results into a single file and then split them up
easily later.
The rest of the lines are package entries, one line for each package
installed on your system. They have the format:
<atime> <ctime> <package-name> <mru-program> <tag>
<package-name> is the name of the Debian package that contains
<mru-program>. <mru-program> is the most recently used program,
static library, or header (.h) file in the package.
<atime> and <ctime> are the access time and creation time of the
<mru-program> on your disk, respectively, represented as the number of
seconds since midnight GMT on January 1, 1970 (i.e. in Unix time_t format).
Linux updates <atime> whenever you open the file; <ctime> was set when you
first installed the package.
<tag> is determined by popularity-contest depending on <atime>, <ctime>, and
the current date. <tag> can be RECENT-CTIME, OLD, or NOFILES.
RECENT-CTIME means that atime is very close to ctime; it's impossible to
tell whether the package was used recently or not, since <atime> is also
updated when <ctime> is set. Normally, this happens because you have
recently upgraded the package to a new version, resetting the <ctime>.
OLD means that the <atime> is more than a month ago; you haven't used the
package for more than a month.
NOFILES means that no files in the package seemed to be programs, so
<atime>, <ctime>, and <mru-program> are invalid.'
REMARKS. The parser will generate events solely based on the <atime> field
and not using <ctime>, to reduce the generation of (possibly many) useless
events all with the same <ctime>. Indeed, that <ctime> will be probably
get from file system and/or package management logs. The <ctime> will be
reported in the log line.
"""
import logging
import pyparsing
from plaso.events import time_events
from plaso.lib import eventdata
from plaso.lib import timelib
from plaso.parsers import manager
from plaso.parsers import text_parser
__author__ = 'Francesco Picasso (francesco.picasso@gmail.com)'
class PopularityContestSessionEvent(time_events.PosixTimeEvent):
"""Convenience class for a Popularity Contest start/end event."""
DATA_TYPE = 'popularity_contest:session:event'
def __init__(self, timestamp, session, status, hostid=None, details=None):
"""Initializes the event object.
Args:
timestamp: microseconds since epoch in UTC, it's the start/end time.
session: the session number.
status: start or end of the session.
hostid: the host uuid.
details: the popularity contest version and host architecture.
"""
super(PopularityContestSessionEvent, self).__init__(
timestamp, eventdata.EventTimestamp.ADDED_TIME)
self.session = session
self.status = status
self.hostid = hostid
self.details = details
class PopularityContestEvent(time_events.PosixTimeEvent):
"""Convenience class for a Popularity Contest line event."""
DATA_TYPE = 'popularity_contest:log:event'
def __init__(self, timestamp, ctime, package, mru, tag=None):
"""Initializes the event object.
Args:
timestamp: microseconds since epoch in UTC, it's the <atime>.
ctime: seconds since epoch in UTC, it's the <ctime>.
package: the installed packaged name, whom mru belongs to.
mru: the recently used app/library from package.
tag: the popularity context tag.
"""
super(PopularityContestEvent, self).__init__(
timestamp, eventdata.EventTimestamp.ACCESS_TIME)
# TODO: adding ctime as is, reconsider a conversion to human readable form.
self.ctime = ctime
self.package = package
self.mru = mru
self.record_tag = tag
class PopularityContestParser(text_parser.PyparsingSingleLineTextParser):
"""Parse popularity contest log files."""
NAME = 'popularity_contest'
DESCRIPTION = u'Parser for popularity contest log files.'
EPOCH = text_parser.PyparsingConstants.INTEGER.setResultsName('epoch')
PACKAGE = pyparsing.Word(pyparsing.printables).setResultsName('package')
MRU = pyparsing.Word(pyparsing.printables).setResultsName('mru')
TAG = pyparsing.QuotedString('<', endQuoteChar='>').setResultsName('tag')
HEADER = (
pyparsing.Literal(u'POPULARITY-CONTEST-').suppress() +
text_parser.PyparsingConstants.INTEGER.setResultsName('session') +
pyparsing.Literal(u'TIME:').suppress() + EPOCH +
pyparsing.Literal('ID:').suppress() +
pyparsing.Word(pyparsing.alphanums, exact=32).setResultsName('id') +
pyparsing.SkipTo(pyparsing.LineEnd()).setResultsName('details'))
FOOTER = (
pyparsing.Literal(u'END-POPULARITY-CONTEST-').suppress() +
text_parser.PyparsingConstants.INTEGER.setResultsName('session') +
pyparsing.Literal(u'TIME:').suppress() + EPOCH)
LOG_LINE = (
EPOCH.setResultsName('atime') + EPOCH.setResultsName('ctime') +
(PACKAGE + TAG | PACKAGE + MRU + pyparsing.Optional(TAG)))
LINE_STRUCTURES = [
('logline', LOG_LINE),
('header', HEADER),
('footer', FOOTER),
]
def VerifyStructure(self, parser_context, line):
"""Verify that this file is a Popularity Contest log file.
Args:
parser_context: A parser context object (instance of ParserContext).
line: A single line from the text file.
Returns:
True if this is the correct parser, False otherwise.
"""
try:
header_struct = self.HEADER.parseString(line)
except pyparsing.ParseException:
logging.debug(u'Not a Popularity Contest log file, invalid header')
return False
if not timelib.Timestamp.FromPosixTime(header_struct.epoch):
logging.debug(u'Invalid Popularity Contest log file header timestamp.')
return False
return True
def ParseRecord(self, parser_context, key, structure):
"""Parse each record structure and return an EventObject if applicable.
Args:
parser_context: A parser context object (instance of ParserContext).
key: An identification string indicating the name of the parsed
structure.
structure: A pyparsing.ParseResults object from a line in the
log file.
Returns:
An event object (instance of EventObject) or None.
"""
# TODO: Add anomaly objects for abnormal timestamps, such as when the log
# timestamp is greater than the session start.
if key == 'logline':
return self._ParseLogLine(structure)
elif key == 'header':
if not structure.epoch:
logging.debug(u'PopularityContestParser, header with invalid epoch.')
return
return PopularityContestSessionEvent(
structure.epoch, unicode(structure.session), u'start', structure.id,
structure.details)
elif key == 'footer':
if not structure.epoch:
logging.debug(u'PopularityContestParser, footer with invalid epoch.')
return
return PopularityContestSessionEvent(
structure.epoch, unicode(structure.session), u'end')
else:
logging.warning(
u'PopularityContestParser, unknown structure: {}.'.format(key))
def _ParseLogLine(self, structure):
"""Gets an event_object or None from the pyparsing ParseResults.
Args:
structure: the pyparsing ParseResults object.
Returns:
event_object: a plaso event or None.
"""
# Required fields are <mru> and <atime> and we are not interested in
# log lines without <mru>.
if not structure.mru:
return
# The <atime> field (as <ctime>) is always present but could be 0.
# In case of <atime> equal to 0, we are in <NOFILES> case, safely return
# without logging.
if not structure.atime:
return
# TODO: not doing any check on <tag> fields, even if only informative
# probably it could be better to check for the expected values.
# TODO: ctime is a numeric string representing seconds since epoch UTC,
# reconsider a conversion to integer together with microseconds usage.
return PopularityContestEvent(
structure.atime, structure.ctime, structure.package, structure.mru,
structure.tag)
manager.ParsersManager.RegisterParser(PopularityContestParser)