Files
volatility3/volatility/plugins/windows/poolscanner.py
T

245 lines
12 KiB
Python

import enum
import logging
import typing
from volatility.framework import constants, interfaces, renderers, validity, exceptions, symbols
from volatility.framework.configuration import requirements
from volatility.framework.interfaces import plugins, configuration
from volatility.framework.layers import scanners
from volatility.framework.renderers import format_hints
from volatility.framework.symbols import intermed
from volatility.framework.symbols.windows import extensions
import volatility.plugins.windows.handles as handles
vollog = logging.getLogger(__name__)
class PoolType(enum.IntEnum):
"""Class to maintain the different possible PoolTypes
The values must be integer powers of 2"""
PAGED = 1
NONPAGED = 2
FREE = 4
class PoolHeaderSymbolTable(intermed.IntermediateSymbolTable):
def __init__(self, *args, **kwargs) -> None:
super().__init__(*args, **kwargs)
self.set_type_class('_POOL_HEADER', extensions._POOL_HEADER)
class PoolConstraint(validity.ValidityRoutines):
"""Class to maintain tag/size/index/type information about Pool header tags"""
def __init__(self,
tag: bytes,
type_name: str,
object_type: typing.Optional[str] = None,
page_type: typing.Optional[PoolType] = None,
size: typing.Optional[typing.Tuple[typing.Optional[int], typing.Optional[int]]] = None,
index: typing.Optional[typing.Tuple[typing.Optional[int], typing.Optional[int]]] = None,
alignment: typing.Optional[int] = 1) -> None:
self.tag = self._check_type(tag, bytes)
self.type_name = type_name
self.object_type = object_type
self.page_type = page_type
self.size = size
self.index = index
self.alignment = alignment
class PoolScanner(plugins.PluginInterface):
"""A generic pool scanner plugin"""
@classmethod
def get_requirements(cls):
return [requirements.TranslationLayerRequirement(name = 'primary',
description = 'Kernel Address Space',
architectures = ["Intel32", "Intel64"]),
requirements.SymbolRequirement(name = "nt_symbols", description = "Windows OS")]
def _generator(self):
constraints = [
# atom tables
PoolConstraint(b'AtmT',
type_name = self.config["nt_symbols"] + constants.BANG + "_RTL_ATOM_TABLE",
size = (200, None),
page_type = PoolType.PAGED | PoolType.NONPAGED | PoolType.FREE),
# processes on windows before windows 8
PoolConstraint(b'Pro\xe3',
type_name = self.config["nt_symbols"] + constants.BANG + "_EPROCESS",
object_type = "Process",
size = (600, None),
page_type = PoolType.PAGED | PoolType.NONPAGED | PoolType.FREE),
# processes on windows starting with windows 8
PoolConstraint(b'Proc',
type_name = self.config["nt_symbols"] + constants.BANG + "_EPROCESS",
object_type = "Process",
size = (600, None),
page_type = PoolType.PAGED | PoolType.NONPAGED | PoolType.FREE),
# files on windows before windows 8
PoolConstraint(b'Fil\xe5',
type_name = self.config["nt_symbols"] + constants.BANG + "_FILE_OBJECT",
object_type = "File",
size = (150, None),
page_type = PoolType.PAGED | PoolType.NONPAGED | PoolType.FREE),
# files on windows starting with windows 8
PoolConstraint(b'File',
type_name = self.config["nt_symbols"] + constants.BANG + "_FILE_OBJECT",
object_type = "File",
size = (150, None),
page_type = PoolType.PAGED | PoolType.NONPAGED | PoolType.FREE),
]
# get the object type map
type_map = handles.Handles.list_objects(context = self.context,
layer_name = self.config["primary"],
symbol_table = self.config["nt_symbols"])
cookie = handles.Handles.find_cookie(context = self.context,
layer_name = self.config["primary"],
symbol_table = self.config["nt_symbols"])
# FIXME: replace these lambdas with real functions
is_windows_10 = lambda: False
is_windows_8_or_later = lambda: False
# FIXME: scanning the primary layer seems very slow (10min on 512mb grrcon)
# start off with the primary virtual layer
scan_layer = self.config['primary']
# switch to a non-virtual layer if necessary
if not is_windows_10():
scan_layer = self.context.memory[scan_layer].config['memory_layer']
for constraint, header in self.pool_scan(self._context,
scan_layer,
self.config['nt_symbols'],
constraints,
alignment = 8):
mem_object = header.get_object(type_name = constraint.type_name,
type_map = type_map,
use_top_down = is_windows_8_or_later(),
object_type = constraint.object_type,
native_layer_name = 'primary',
cookie = cookie)
if mem_object is None:
vollog.log(constants.LOGLEVEL_VVV, "Cannot create an instance of {}".format(constraint.type_name))
continue
# generate some type-specific info for sanity checking
if constraint.object_type == "Process":
name = mem_object.ImageFileName.cast("string",
max_length = mem_object.ImageFileName.vol.count,
errors = "replace")
elif constraint.object_type == "File":
try:
name = mem_object.FileName.String
except exceptions.PagedInvalidAddressException:
vollog.log(constants.LOGLEVEL_VVV, "Skipping file at {0:#x}".format(mem_object.vol.offset))
continue
else:
name = renderers.NotApplicableValue()
yield (0, (constraint.type_name,
format_hints.Hex(header.vol.offset),
header.vol.layer_name,
name))
@classmethod
def pool_scan(cls,
context: interfaces.context.ContextInterface,
layer_name: str,
symbol_table: str,
pool_constraints: typing.List[PoolConstraint],
alignment: int = 8) -> typing.Generator[typing.Tuple[PoolConstraint,
interfaces.objects.ObjectInterface], None, None]:
"""Returns the _POOL_HEADER object (based on the symbol_table template) after scanning through layer_name
returning all headers that match any of the constraints provided. Only one constraint can be provided per tag"""
# Setup the pattern
constraint_lookup = {} # type: typing.Dict[bytes, typing.List[PoolConstraint]]
for constraint in pool_constraints:
temp_list = constraint_lookup.get(constraint.tag, [])
temp_list.append(constraint)
constraint_lookup[constraint.tag] = temp_list
# Setup the pool header and offset differential
try:
module = context.module(symbol_table, layer_name, offset = 0)
header_type = module.get_type('_POOL_HEADER')
except exceptions.SymbolError:
# We have to manually load a symbol table
if symbols.symbol_table_is_64bit(context, symbol_table):
# FIXME: Do proper test for is_win_7
is_win_7 = False
if is_win_7:
pool_header_json_filename = "poolheader-x64-win7"
else:
pool_header_json_filename = "poolheader-x64"
else:
pool_header_json_filename = "poolheader-x86"
new_table_name = PoolHeaderSymbolTable.create(context = context,
config_path = configuration.path_join(
context.symbol_space[symbol_table].config_path,
"poolheader"
),
sub_path = "windows",
filename = pool_header_json_filename,
table_mapping = {'nt_symbols': symbol_table})
module = context.module(new_table_name, layer_name, offset = 0)
header_type = module.get_type('_POOL_HEADER')
header_offset = header_type.relative_child_offset('PoolTag')
# Run the scan locating the offsets of a particular tag
layer = context.memory[layer_name]
scanner = scanners.MultiStringScanner([c for c in constraint_lookup.keys()])
for offset, pattern in layer.scan(context, scanner):
for constraint in constraint_lookup[pattern]:
header = module.object(type_name = "_POOL_HEADER", offset = offset - header_offset)
# Size check
if constraint.size is not None:
if constraint.size[0]:
if (alignment * header.BlockSize) < constraint.size[0]:
continue
if constraint.size[1]:
if (alignment * header.BlockSize) > constraint.size[1]:
continue
# Type check
if constraint.page_type is not None:
checks_pass = False
if (constraint.page_type & PoolType.FREE) and header.PoolType == 0:
checks_pass = True
elif (constraint.page_type & PoolType.PAGED) and header.PoolType % 2 == 0 and header.PoolType > 0:
checks_pass = True
elif (constraint.page_type & PoolType.NONPAGED) and header.PoolType % 2 == 1:
checks_pass = True
if not checks_pass:
continue
if constraint.index is not None:
if constraint.index[0]:
if header.index < constraint.index[0]:
continue
if constraint.index[1]:
if header.index > constraint.index[1]:
continue
# We found one that passed!
yield (constraint, header)
def run(self) -> renderers.TreeGrid:
return renderers.TreeGrid([("Tag", str),
("Offset", format_hints.Hex),
("Layer", str),
("Name", str)],
self._generator())