def evaluate_llil(self, state, llil):
# Interpreter for LLIL instructions, using data from state
if llil.operation == LowLevelILOperation.LLIL_CONST:
return llil.operands[0]
elif llil.operation == LowLevelILOperation.LLIL_CONST_PTR:
return llil.operands[0]
elif llil.operation == LowLevelILOperation.LLIL_REG:
reg = llil.operands[0].name
return state.registers[reg]
elif llil.operation == LowLevelILOperation.LLIL_LOAD:
addr = self.evaluate_llil(state, llil.operands[0])
# Have to read from addr llil.size bytes
reader = BinaryReader(state.memory_view)
reader.seek(addr)
if llil.size == 1:
deref = reader.read8()
elif llil.size == 2:
deref = reader.read16()
elif llil.size == 4:
deref = reader.read32()
else:
deref = reader.read64()
# Unimplemented: 128-bit, etc
return deref
elif llil.operation == LowLevelILOperation.LLIL_ADD:
return self.evaluate_llil(state,
llil.operands[0]) + self.evaluate_llil(
state, llil.operands[1])
elif llil.operation == LowLevelILOperation.LLIL_SUB:
return self.evaluate_llil(state,
llil.operands[0]) - self.evaluate_llil(
state, llil.operands[1])
elif llil.operation == LowLevelILOperation.LLIL_MUL:
return self.evaluate_llil(state,
llil.operands[0]) * self.evaluate_llil(
state, llil.operands[1])
elif llil.operation == LowLevelILOperation.LLIL_LSL:
return self.evaluate_llil(state,
llil.operands[0]) << self.evaluate_llil(
state, llil.operands[1])
elif llil.operation == LowLevelILOperation.LLIL_LSR:
return self.evaluate_llil(state,
llil.operands[0]) >> self.evaluate_llil(
state, llil.operands[1])
else:
raise NotImplementedError('todo: evaluate llil for %s' %
llil.operation)
def evaluate_llil(self, state, llil):
if llil.operation == LowLevelILOperation.LLIL_CONST:
return llil.operands[0]
elif llil.operation == LowLevelILOperation.LLIL_CONST_PTR:
return llil.operands[0]
elif llil.operation == LowLevelILOperation.LLIL_REG:
reg = llil.operands[0].name
return state.registers[reg]
elif llil.operation == LowLevelILOperation.LLIL_LOAD:
addr = self.evaluate_llil(state, llil.operands[0])
reader = BinaryReader(state.memory_view)
reader.seek(addr)
# TODO: 32-bit
deref = reader.read64()
return deref
elif llil.operation == LowLevelILOperation.LLIL_ADD:
return sum(self.evaluate_llil(state, op) for op in llil.operands)
else:
raise NotImplementedError('todo: evaluate llil for %s' %
llil.operation)
class DelphiVMT(object):
'''
TODO: Doc
'''
def __init__(self,
bv: BinaryView,
delphi_version: int,
address: int,
analyzer: DelphiAnalyzer,
offset_ptr_size=-1):
self._offset_ptr_size = offset_ptr_size if offset_ptr_size > 0 else bv.address_size
self._vmt_address = address
self._analyzer = analyzer
self._is_valid = False
self._bv = bv
self._br = BinaryReader(bv)
self._vmt_offsets = analyzer.vmt_offsets
self._class_name = ''
self._instance_size = 0
self._parent_vmt = 0
self._table_list: Mapping[int, str] = {}
self._virtual_methods: Mapping[int, str] = {}
if not self._check_self_ptr():
return
if not self._resolve_name():
return
if not self._resolve_instance_size():
return
if not self._resolve_parent_vmt():
return
if not self._resolve_table_list():
return
if not self._resolve_virtual_methods():
return
self._is_valid = True
def __repr__(self):
return str(self)
def __str__(self):
if not self._is_valid:
return f'<InvalidVmt address=0x{self._vmt_address:08X}>'
return (f'<{self._class_name} start=0x{self.start:08X} '
f'instance_size=0x{self._instance_size:X}>')
## Properties
@property
def vmt_address(self) -> int:
return self._vmt_address
@property
def is_valid(self) -> bool:
return self._is_valid
@property
def class_name(self) -> str:
return self._class_name
@property
def instance_size(self) -> int:
return self._instance_size
@property
def parent_vmt(self) -> int:
return self._parent_vmt
@property
def table_list(self) -> Mapping[int, str]:
return self._table_list
@property
def virtual_methods(self) -> Mapping[int, str]:
return self._virtual_methods
@property
def vmt_offsets(self) -> VMTOffsets:
return copy.copy(self._vmt_offsets)
@property
def start(self) -> int:
return self._vmt_address + self._vmt_offsets.cVmtSelfPtr
@property
def size(self) -> int:
end = 0 # ????
return end - self.start
@property
def offset_ptr_size(self) -> int:
return self._offset_ptr_size
@property
def br_offset(self) -> int:
return self._br.offset
## Public API
def seek_to_code(self, address: int) -> bool:
if not self._is_valid_addr(address):
return False
self._br.seek(address)
return True
def seek_to_code_offset(self, offset: int) -> bool:
if not self._is_valid_addr(self._analyzer.start + offset):
return False
self._br.seek(self._analyzer.start + offset)
return True
def seek_to_vmt_offset(self, offset: int) -> bool:
if not self._is_valid_addr(self._vmt_address + offset):
return False
self._br.seek(self._vmt_address + offset)
return True
def read8(self) -> Union[None, int]:
return self._br.read8()
def read_ptr(self) -> Union[None, int]:
if self._offset_ptr_size == 4:
return self._br.read32()
elif self._offset_ptr_size == 8:
return self._br.read64()
## Protected methods
def _check_self_ptr(self) -> bool:
if not self.seek_to_vmt_offset(self._vmt_offsets.cVmtSelfPtr):
return False
self_ptr = self.read_ptr()
return self_ptr == self._vmt_address
def _resolve_name(self) -> bool:
class_name_addr = self._get_class_name_addr()
if class_name_addr is None:
return False
self._br.seek(class_name_addr)
name_len = self._br.read8()
if name_len == 0:
BNLogger.log(
f'Care, VMT without name (len: 0) detected at 0x{self._vmt_address:08X}',
LogLevel.WarningLog)
class_name = self._br.read(name_len)
if MATCH_CLASS_NAME.match(class_name) is None:
return False
self._class_name = class_name.decode()
return True
def _resolve_instance_size(self) -> bool:
if not self.seek_to_vmt_offset(self._vmt_offsets.cVmtInstanceSize):
return False
self._instance_size = self.read_ptr()
return True
def _resolve_parent_vmt(self) -> bool:
if not self.seek_to_vmt_offset(self._vmt_offsets.cVmtParent):
return False
self._parent_vmt = self.read_ptr()
return True
def _resolve_virtual_methods(self) -> bool:
class_name_addr = self._get_class_name_addr()
if class_name_addr is None:
return False
offsets = self.vmt_offsets.__dict__.items()
offset_map = {y: x for x, y in offsets}
tables_addr = self._table_list.keys()
if not self.seek_to_vmt_offset(self._vmt_offsets.cVmtParent +
self._offset_ptr_size):
return False
while self._br.offset < class_name_addr and self._br.offset not in tables_addr:
field_value = self.read_ptr()
if field_value == 0:
continue
if not self._is_valid_addr(field_value):
prev_offset = self._br.offset - self._offset_ptr_size
raise RuntimeError(
f'Invalid code address deteted at 0x{prev_offset:08X} '
'({self.class_name})\n If you think it\'s a bug, please open an issue on '
'Github with the used binary or the full VMT (fields + VMT) as an attachment'
)
field_offset = self._br.offset - self._vmt_address - self._offset_ptr_size
if field_offset in offset_map:
# Remove `cVmt` prefix
method_name = f'{self.class_name}.{offset_map[field_offset][4:]}'
else:
method_name = f'{self.class_name}.sub_{field_value:x}'
self._virtual_methods[field_value] = method_name
return True
def _resolve_table_list(self) -> bool:
if not self.seek_to_vmt_offset(self.vmt_offsets.cVmtIntfTable):
return False
offsets = self._vmt_offsets.__dict__.items()
offset_map = {y: x[4:] for x, y in offsets}
stop_at = self._vmt_address + self._vmt_offsets.cVmtClassName
while self._br.offset != stop_at:
prev_br_offset = self._br.offset
address = self.read_ptr()
if address < 1:
continue
if not self._is_valid_addr(address):
raise RuntimeError('Invalid table address detected')
self._table_list[address] = offset_map[prev_br_offset -
self._vmt_address]
return True
def _is_valid_addr(self, addy: int, allow_null=False) -> bool:
if addy == 0:
return allow_null
return addy >= self._analyzer.start and addy < self._analyzer.end
def _get_class_name_addr(self) -> Union[None, int]:
if not self.seek_to_vmt_offset(self._vmt_offsets.cVmtClassName):
return None
class_name_addr = self.read_ptr()
if not self._is_valid_addr(class_name_addr):
return None
return class_name_addr
class DelphiAnalyzer(object):
'''
TODO: Doc
'''
def __init__(self,
bv: BinaryView,
delphi_version: int,
offset_ptr_size=-1,
start=-1,
end=-1):
self._offset_ptr_size = offset_ptr_size if offset_ptr_size > 0 else bv.address_size
self._start = start if start >= 0 else bv.start
self._end = end if end > 0 else bv.end
self._vmt_list: List[DelphiVMT] = []
self._bv = bv
self._br = BinaryReader(bv)
self._delphi_version = delphi_version
self._vmt_offsets = VMTOffsets(delphi_version, self._offset_ptr_size)
# Not really sure about this but it's working on my test binary (Win64 Delphi v10.3)
# Need to check offsets for macOS
# I'll clean that later
if self._bv.view_type == 'PE' and self._offset_ptr_size == 8:
for x, y in self._vmt_offsets.__dict__.items():
setattr(self._vmt_offsets, x, y + -24)
## Properties
@property
def start(self) -> int:
return self._start
@property
def end(self) -> int:
return self._end
@property
def delphi_version(self) -> int:
return self._delphi_version
@property
def vmt_list(self) -> List[DelphiVMT]:
return self._vmt_list
@property
def vmt_offsets(self) -> VMTOffsets:
return copy.copy(self._vmt_offsets)
## Public API
def update_analysis_and_wait(self,
callback: Callable[[DelphiVMT], None] = None):
self._vmt_list = []
self._seek_to_offset(0)
while True:
addy = self._get_possible_vmt()
if addy is None:
break
delphi_vmt = DelphiVMT(self._bv, self._delphi_version, addy, self,
self._offset_ptr_size)
if not delphi_vmt.is_valid:
continue
self._vmt_list.append(delphi_vmt)
if callback is not None:
callback(delphi_vmt)
## Protected methods
def _seek_to_offset(self, offset: int):
self._br.seek(self._start + offset)
def _read_ptr(self) -> Union[None, int]:
if self._offset_ptr_size == 4:
return self._br.read32()
elif self._offset_ptr_size == 8:
return self._br.read64()
def _get_possible_vmt(self) -> int:
while self._br.offset <= self._end - self._offset_ptr_size - 1:
begin = self._br.offset
if not self._bv.is_valid_offset(begin):
self._br.seek_relative(self._offset_ptr_size)
continue
class_vmt = self._read_ptr()
if class_vmt is None:
# If BinaryReader can't read, it will not update the offset
self._br.seek_relative(self._offset_ptr_size)
continue
if begin == class_vmt + self._vmt_offsets.cVmtSelfPtr:
return class_vmt
