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

192 lines
7.1 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 the SAM Users & Names key plugin."""
import construct
import logging
from plaso.events import windows_events
from plaso.lib import binary
from plaso.lib import eventdata
from plaso.lib import timelib
from plaso.parsers import winreg
from plaso.parsers.winreg_plugins import interface
__author__ = 'Preston Miller, dpmforensics.com, github.com/prmiller91'
class UsersPlugin(interface.KeyPlugin):
"""SAM Windows Registry plugin for Users Account information."""
NAME = 'winreg_sam_users'
DESCRIPTION = u'Parser for SAM Users and Names Registry keys.'
REG_KEYS = [u'\\SAM\\Domains\\Account\\Users']
REG_TYPE = 'SAM'
F_VALUE_STRUCT = construct.Struct(
'f_struct', construct.Padding(8), construct.ULInt64('last_login'),
construct.Padding(8), construct.ULInt64('password_reset'),
construct.Padding(16), construct.ULInt16('rid'), construct.Padding(16),
construct.ULInt8('login_count'))
V_VALUE_HEADER = construct.Struct(
'v_header', construct.Array(11, construct.ULInt32('values')))
V_VALUE_HEADER_SIZE = 0xCC
def GetEntries(
self, parser_context, key=None, registry_type=None, file_entry=None,
parser_chain=None, **unused_kwargs):
"""Collect data from Users and Names and produce event objects.
Args:
parser_context: A parser context object (instance of ParserContext).
key: Optional Registry key (instance of winreg.WinRegKey).
The default is None.
registry_type: Optional Registry type string. The default is None.
file_entry: Optional file entry object (instance of dfvfs.FileEntry).
The default is None.
parser_chain: Optional string containing the parsing chain up to this
point. The default is None.
"""
name_dict = {}
name_key = key.GetSubkey('Names')
if not name_key:
logging.error(u'Unable to locate Names key.')
return
values = [(v.name, v.last_written_timestamp) for v in name_key.GetSubkeys()]
name_dict = dict(values)
for subkey in key.GetSubkeys():
text_dict = {}
if subkey.name == 'Names':
continue
text_dict['user_guid'] = subkey.name
parsed_v_value = self._ParseVValue(subkey)
if not parsed_v_value:
logging.error(u'V Value was not succesfully parsed by ParseVValue.')
return
username = parsed_v_value[0]
full_name = parsed_v_value[1]
comments = parsed_v_value[2]
if username:
text_dict['username'] = username
if full_name:
text_dict['full_name'] = full_name
if comments:
text_dict['comments'] = comments
if name_dict:
account_create_time = name_dict.get(text_dict.get('username'), 0)
else:
account_create_time = 0
f_data = self._ParseFValue(subkey)
last_login_time = timelib.Timestamp.FromFiletime(f_data.last_login)
password_reset_time = timelib.Timestamp.FromFiletime(
f_data.password_reset)
text_dict['account_rid'] = f_data.rid
text_dict['login_count'] = f_data.login_count
if account_create_time > 0:
event_object = windows_events.WindowsRegistryEvent(
account_create_time, key.path, text_dict,
usage=eventdata.EventTimestamp.ACCOUNT_CREATED,
offset=key.offset, registry_type=registry_type,
source_append=u'User Account Information')
parser_context.ProduceEvent(
event_object, parser_chain=parser_chain, file_entry=file_entry)
if last_login_time > 0:
event_object = windows_events.WindowsRegistryEvent(
last_login_time, key.path, text_dict,
usage=eventdata.EventTimestamp.LAST_LOGIN_TIME,
offset=key.offset,
registry_type=registry_type,
source_append=u'User Account Information')
parser_context.ProduceEvent(
event_object, parser_chain=parser_chain, file_entry=file_entry)
if password_reset_time > 0:
event_object = windows_events.WindowsRegistryEvent(
password_reset_time, key.path, text_dict,
usage=eventdata.EventTimestamp.LAST_PASSWORD_RESET,
offset=key.offset, registry_type=registry_type,
source_append=u'User Account Information')
parser_context.ProduceEvent(
event_object, parser_chain=parser_chain, file_entry=file_entry)
def _ParseVValue(self, key):
"""Parses V value and returns name, fullname, and comments data.
Args:
key: Registry key (instance of winreg.WinRegKey).
Returns:
name: Name data parsed with name start and length values.
fullname: Fullname data parsed with fullname start and length values.
comments: Comments data parsed with comments start and length values.
"""
v_value = key.GetValue('V')
if not v_value:
logging.error(u'Unable to locate V Value in key.')
return
try:
structure = self.V_VALUE_HEADER.parse(v_value.data)
except construct.FieldError as exception:
logging.error(
u'Unable to extract V value header data: {:s}'.format(exception))
return
name_offset = structure.values()[0][3] + self.V_VALUE_HEADER_SIZE
full_name_offset = structure.values()[0][6] + self.V_VALUE_HEADER_SIZE
comments_offset = structure.values()[0][9] + self.V_VALUE_HEADER_SIZE
name_raw = v_value.data[
name_offset:name_offset + structure.values()[0][4]]
full_name_raw = v_value.data[
full_name_offset:full_name_offset + structure.values()[0][7]]
comments_raw = v_value.data[
comments_offset:comments_offset + structure.values()[0][10]]
name = binary.ReadUtf16(name_raw)
full_name = binary.ReadUtf16(full_name_raw)
comments = binary.ReadUtf16(comments_raw)
return name, full_name, comments
def _ParseFValue(self, key):
"""Parses F value and returns parsed F data construct object.
Args:
key: Registry key (instance of winreg.WinRegKey).
Returns:
f_data: Construct parsed F value containing rid, login count,
and timestamp information.
"""
f_value = key.GetValue('F')
if not f_value:
logging.error(u'Unable to locate F Value in key.')
return
try:
f_data = self.F_VALUE_STRUCT.parse(f_value.data)
except construct.FieldError as exception:
logging.error(
u'Unable to extract F value data: {:s}'.format(exception))
return
return f_data
winreg.WinRegistryParser.RegisterPlugin(UsersPlugin)