def __init__(self, reader: MemoryViewReader):
self.name_index = reader.read_int()
self.super_name_index = reader.read_int()
self.flags = ClassFlags(reader.read_u8())
if ClassFlags.PROTECTED_NS in self.flags:
self.protected_namespace_index = reader.read_int()
self.interface_indices = read_array(reader, MemoryViewReader.read_int)
self.init_index = reader.read_int()
self.traits = read_array(reader, ASTrait)
def __init__(self, reader: MemoryViewReader):
self.minor_version = reader.read_u16()
self.major_version = reader.read_u16()
self.constant_pool = ASConstantPool(reader)
self.methods = read_array(reader, ASMethod)
self.metadata = read_array(reader, ASMetadata)
class_count = reader.read_int()
self.instances = read_array(reader, ASInstance, class_count)
self.classes = read_array(reader, ASClass, class_count)
self.scripts = read_array(reader, ASScript)
self.method_bodies = read_array(reader, ASMethodBody)
def __init__(self, reader: MemoryViewReader):
self.param_count = reader.read_int()
self.return_type_index = reader.read_int()
self.param_type_indices = read_array(reader, MemoryViewReader.read_int,
self.param_count)
self.name_index = reader.read_int()
self.flags = MethodFlags(reader.read_u8())
if MethodFlags.HAS_OPTIONAL in self.flags:
self.options = read_array(reader, ASOptionDetail)
if MethodFlags.HAS_PARAM_NAMES in self.flags:
self.param_name_indices = read_array(reader,
MemoryViewReader.read_int,
self.param_count)
def parse_swf(input_: Union[memoryview, bytes]) -> Iterable[Tag]:
"""
Parse SWF file and get an iterable of its tags.
"""
reader = MemoryViewReader(input_)
signature = Signature(reader.read_u8())
assert reader.read_u16() == 0x5357
reader.skip(1) # version
reader.skip(4) # file length
reader = decompress(reader, signature)
reader.skip_rect()
reader.skip(4) # frame rate and frame count
return read_tags(reader)
def read_array_with_default(reader: MemoryViewReader,
read: Callable[[MemoryViewReader], T],
default: Optional[T]) -> List[T]:
"""
Read variable-length array where 0-th element has a "special meaning".
"""
return [default, *(read(reader) for _ in range(1, reader.read_int()))]
def read_array(reader: MemoryViewReader,
read: Callable[[MemoryViewReader], T],
size: Optional[int] = None) -> List[T]:
"""
Read variable-length array.
"""
if size is None:
size = reader.read_int()
return [read(reader) for _ in range(size)]
def __init__(self, reader: MemoryViewReader):
self.name_index = reader.read_int()
kind = reader.read_u8()
self.kind = TraitKind(kind & 0x0F)
self.attributes = TraitAttributes(kind >> 4)
if self.kind in (TraitKind.SLOT, TraitKind.CONST):
self.data = ASTraitSlot(reader)
elif self.kind == TraitKind.CLASS:
self.data = ASTraitClass(reader)
elif self.kind == TraitKind.FUNCTION:
self.data = ASTraitFunction(reader)
elif self.kind in (TraitKind.METHOD, TraitKind.GETTER,
TraitKind.SETTER):
self.data = ASTraitMethod(reader)
else:
assert False, 'unreachable code'
if TraitAttributes.METADATA in self.attributes:
self.metadata = read_array(reader, MemoryViewReader.read_int)
def __init__(self, reader: MemoryViewReader):
self.method_index = reader.read_int()
self.max_stack = reader.read_int()
self.local_count = reader.read_int()
self.init_scope_depth = reader.read_int()
self.max_scope_depth = reader.read_int()
self.code = reader.read(reader.read_int())
self.exceptions = read_array(reader, ASException)
self.traits = read_array(reader, ASTrait)
def execute_code(self, code: memoryview, environment: MethodEnvironment) -> Any:
"""
Execute the byte-code and get a return value.
"""
reader = MemoryViewReader(code)
while True:
try:
# FIXME: cache already read instructions.
avm2.abc.instructions.read_instruction(reader).execute(self, environment)
except ASReturnException as e:
return e.return_value
except ASJumpException as e:
reader.position += e.offset
def __init__(self, reader: MemoryViewReader):
self.kind = MultinameKind(reader.read_u8())
if self.kind in (MultinameKind.Q_NAME, MultinameKind.Q_NAME_A):
self.namespace_index = reader.read_int()
self.name_index = reader.read_int()
elif self.kind in (MultinameKind.RTQ_NAME, MultinameKind.RTQ_NAME_A):
self.name_index = reader.read_int()
elif self.kind in (MultinameKind.RTQ_NAME_L,
MultinameKind.RTQ_NAME_LA):
pass
elif self.kind in (MultinameKind.MULTINAME, MultinameKind.MULTINAME_A):
self.name_index = reader.read_int()
self.namespace_set_index = reader.read_int()
elif self.kind in (MultinameKind.MULTINAME_L,
MultinameKind.MULTINAME_LA):
self.namespace_set_index = reader.read_int()
elif self.kind == MultinameKind.TYPE_NAME:
self.q_name_index = reader.read_int()
self.type_indices = read_array(reader, MemoryViewReader.read_int)
else:
assert False, 'unreachable code'
def decompress(reader: MemoryViewReader,
signature: Signature) -> MemoryViewReader:
"""
Decompress the rest of an SWF file, depending on its signature.
"""
if signature == Signature.UNCOMPRESSED:
return reader
if signature == Signature.LZMA:
# https://stackoverflow.com/a/39777419/359730
reader.skip(4) # skip compressed length
return MemoryViewReader(
lzma.decompress(
reader.read(5).tobytes() +
b'\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF' +
reader.read_all().tobytes()))
if signature == Signature.ZLIB:
return MemoryViewReader(zlib.decompress(reader.read_all()))
assert False, 'unreachable code'
def read_tags(reader: MemoryViewReader) -> Iterable[Tag]:
"""
Read tags from the stream and get an iterable of tags.
"""
while not reader.is_eof():
code_length = reader.read_u16()
length = code_length & 0b111111
if length == 0x3F:
# Long tag header.
length = reader.read_u32()
try:
type_ = TagType(code_length >> 6)
except ValueError:
# Unknown tag type. Skip the tag.
reader.skip(length)
else:
yield Tag(type_=type_, raw=reader.read(length))
def __init__(self, reader: MemoryViewReader):
self.slot_id = reader.read_int()
self.type_name_index = reader.read_int()
self.vindex = reader.read_int()
if self.vindex:
self.vkind = ConstantKind(reader.read_u8())
def __init__(self, raw: memoryview):
reader = MemoryViewReader(raw)
self.flags = DoABCTagFlags(reader.read_u32())
self.name = reader.read_string()
self.abc_file = reader.read_all()
def __init__(self, reader: MemoryViewReader):
self.kind = NamespaceKind(reader.read_u8())
self.name_index = reader.read_int()
def __init__(self, reader: MemoryViewReader):
self.from_ = reader.read_int()
self.to = reader.read_int()
self.target = reader.read_int()
self.exc_type_index = reader.read_int()
self.var_name_index = reader.read_int()
def __init__(self, reader: MemoryViewReader):
self.init_index = reader.read_int()
self.traits = read_array(reader, ASTrait)
def __init__(self, reader: MemoryViewReader):
self.disposition_id = reader.read_int()
self.method_index = reader.read_int()
def abc_file(do_abc_tag: DoABCTag) -> ABCFile:
return ABCFile(MemoryViewReader(do_abc_tag.abc_file))
def __init__(self, reader: MemoryViewReader):
self.key_index = reader.read_int()
self.value_index = reader.read_int()
def __init__(self, reader: MemoryViewReader):
self.name_index = reader.read_int()
self.items = read_array(reader, ASItem)
def __init__(self, reader: MemoryViewReader):
self.value = reader.read_int()
self.kind = ConstantKind(reader.read_u8())
def read_string(reader: MemoryViewReader) -> str:
return reader.read(reader.read_int()).tobytes().decode('utf-8')
def __init__(self, reader: MemoryViewReader):
self.slot_id = reader.read_int()
self.class_index = reader.read_int()
def execute_do_abc_tag(do_abc_tag: DoABCTag) -> VirtualMachine:
"""
Create a virtual machine and execute the tag.
"""
return VirtualMachine(ABCFile(MemoryViewReader(do_abc_tag.abc_file)))
def __init__(self, reader: MemoryViewReader):
self.slot_id = reader.read_int()
self.function_index = reader.read_int()