def __init__(self, reader: StructReader):
reader.bigendian = True
self.max_stack = reader.u16()
self.max_locals = reader.u16()
self.disassembly: List[JvOpCode] = []
with StructReader(reader.read(reader.u32())) as code:
code.bigendian = True
while not code.eof:
self.disassembly.append(JvOpCode(code, pool=self.pool))
self.exceptions = [JvException(reader) for _ in range(reader.u16())]
self.attributes = [JvAttribute(reader) for _ in range(reader.u16())]
def __init__(self, reader: StructReader):
if reader.read(4) != self.SIGNATURE:
raise ValueError
self.disk_number = reader.u16()
self.start_disk_number = reader.u16()
self.entries_on_disk = reader.u16()
self.entries_in_directory = reader.u16()
self.directory_size = reader.u32()
self.directory_offset = reader.u32()
try:
cl = reader.u32()
self.comment = cl and reader.read(cl) or None
except EOFError:
self.comment = None
def _decompress_xpress(self,
reader: StructReader,
writer: MemoryFile,
target: Optional[int] = None) -> bytearray:
if target is not None:
target += writer.tell()
flags = BitBufferedReader(reader)
nibble_cache = None
while not reader.eof:
if target is not None and writer.tell() >= target:
return
if not flags.next():
writer.write(reader.read(1))
continue
offset, length = divmod(reader.u16(), 8)
offset += 1
if length == 7:
length = nibble_cache
if length is None:
length_pair = reader.u8()
nibble_cache = length_pair >> 4
length = length_pair & 0xF
else:
nibble_cache = None
if length == 15:
length = reader.u8()
if length == 0xFF:
length = reader.u16() or reader.u32()
length -= 22
if length < 0:
raise RuntimeError(
F'Invalid match length of {length} for long delta sequence'
)
length += 15
length += 7
length += 3
writer.replay(offset, length)
def __init__(self, reader: StructReader):
if reader.read(4) != self.SIGNATURE:
raise ValueError
self.version_made_by = reader.u16()
self.version_to_extract = reader.u16()
self.flags = reader.u16()
self.compression = reader.u16()
self.date = datefix.dostime(reader.u32())
self.crc32 = reader.u32()
self.compressed_size = reader.u32()
self.decompressed_size = reader.u32()
len_filename = reader.u16()
len_extra = reader.u16()
len_comment = reader.u16()
self.disk_nr_start = reader.u16()
self.internal_attributes = reader.u16()
self.external_attributes = reader.u32()
self.header_offset = reader.u32()
self.filename = len_filename and reader.read(len_filename) or None
self.extra = len_extra and reader.read(len_extra) or None
self.comment = len_comment and reader.read(len_comment) or None
def __init__(self, reader: StructReader):
with StreamDetour(reader):
self.code = opc(reader.read_byte())
self.table: Optional[Dict[int, int]] = None
try:
fmt = self.OPC_ARGMAP[self.code]
except KeyError:
self.arguments = []
else:
self.arguments = list(reader.read_struct(fmt))
if self.code == opc.newarray:
self.arguments = [JvBaseType(reader.read_byte())]
elif self.code in self.OPC_CONSTPOOL:
try:
self.arguments[0] = self.pool[self.arguments[0] - 1]
except (AttributeError, IndexError):
pass
elif self.code == opc.lookupswitch:
reader.byte_align(blocksize=4)
default, npairs = reader.read_struct('LL')
pairs = reader.read_struct(F'{npairs*2}L')
self.table = dict(zip(*([iter(pairs)] * 2)))
self.table[None] = default
elif self.code == opc.tableswitch:
reader.byte_align(blocksize=4)
default, low, high = reader.read_struct('LLL')
assert low <= high
offsets = reader.read_struct(F'{high-low+1}L')
self.table = {k + low: offset for k, offset in enumerate(offsets)}
self.table[None] = default
elif self.code == opc.wide:
argop = opc(reader.get_byte())
self.arguments = (argop, reader.u16())
if argop == opc.iinc:
self.arguments += reader.i16(),
else:
assert argop in (
opc.iload, opc.istore,
opc.fload, opc.fstore,
opc.aload, opc.astore,
opc.lload, opc.lstore,
opc.dload, opc.dstore,
opc.ret)
offset = reader.tell()
self.raw = bytes(reader.read(offset - reader.tell()))
def __init__(self, reader: StructReader):
reader.bigendian = True
if reader.read(4).hex() != 'cafebabe':
raise ValueError('class file magic missing.')
minor = reader.u16()
major = reader.u16()
self.version = (major, minor)
self.pool: List[Union[Struct, int, float, str]] = []
self._read_pool(reader)
self.strings: List[str] = {
s.value for s in self.pool if isinstance(s, Struct) and s.tag == JvConstType.String}
self.access = JvAccessFlags(reader)
self.this = reader.u16()
self.parent = reader.u16()
try:
self.interfaces = [self.pool[reader.u16()]
for _ in range(reader.u16())]
except IndexError:
raise ValueError('Failed parsing Interfaces.')
try:
self.fields = [JvClassMember(reader, pool=self.pool)
for _ in range(reader.u16())]
except IndexError:
raise ValueError('Failed parsing Fields.')
try:
self.methods = [JvClassMember(reader, pool=self.pool)
for _ in range(reader.u16())]
except IndexError:
raise ValueError('Failed parsing Methods.')
try:
self.attributes = [JvAttribute(reader, pool=self.pool)
for _ in range(reader.u16())]
except IndexError:
raise ValueError('Failed parsing Attributes.')
def _decompress_xpress_huffman(self,
reader: StructReader,
writer: MemoryFile,
target: Optional[int] = None,
max_chunk_size: int = 0x10000) -> None:
limit = writer.tell()
if target is not None:
target += limit
while not reader.eof:
if reader.remaining_bytes < XPRESS_NUM_SYMBOLS // 2:
raise IndexError(
F'There are only {reader.remaining_bytes} bytes reamining in the input buffer,'
F' but at least {XPRESS_NUM_SYMBOLS//2} are required to read a Huffman table.'
)
table = bytearray(
reader.read_integer(4) for _ in range(XPRESS_NUM_SYMBOLS))
table = make_huffman_decode_table(table, XPRESS_TABLEBITS,
XPRESS_MAX_CODEWORD_LEN)
limit = limit + max_chunk_size
flags = BitBufferedReader(reader, 16)
while True:
position = writer.tell()
if position == target:
if reader.remaining_bytes:
self.log_info(
F'chunk decompressed with {reader.remaining_bytes} bytes remaining in input buffer'
)
return
if position >= limit:
if position > limit:
limit = position
self.log_info(
F'decompression of one chunk generated more than the limit of {max_chunk_size} bytes'
)
flags.collect()
break
try:
sym = flags.huffman_symbol(table, XPRESS_TABLEBITS,
XPRESS_MAX_CODEWORD_LEN)
except EOFError:
self.log_debug('end of file while reading huffman symbol')
break
if sym < XPRESS_NUM_CHARS:
writer.write_byte(sym)
continue
length = sym & 0xF
offsetlog = (sym >> 4) & 0xF
flags.collect()
if reader.eof:
break
offset = (1 << offsetlog) | flags.read(offsetlog)
if length == 0xF:
nudge = reader.read_byte()
if nudge < 0xFF:
length += nudge
else:
length = reader.u16() or reader.u32()
length += XPRESS_MIN_MATCH_LEN
writer.replay(offset, length)
def decompress_stream(self, data: ByteString, LZOv1: bool = False) -> bytearray:
"""
An implementation of LZO decompression. We use the article
"[LZO stream format as understood by Linux's LZO decompressor](https://www.kernel.org/doc/html/latest/staging/lzo.html)"
as a reference since no proper specification is available.
"""
def integer() -> int:
length = 0
while True:
byte = src.read_byte()
if byte:
return length + byte
length += 0xFF
if length > 0x100000:
raise LZOError('Too many zeros in integer encoding.')
def literal(count):
dst.write(src.read_bytes(count))
def copy(distance: int, length: int):
if distance > len(dst):
raise LZOError(F'Distance {distance} > bufsize {len(dst)}')
buffer = dst.getbuffer()
if distance > length:
start = len(buffer) - distance
end = start + length
dst.write(buffer[start:end])
else:
block = buffer[-distance:]
while len(block) < length:
block += block[:length - len(block)]
if len(block) > length:
block[length:] = ()
dst.write(block)
src = StructReader(memoryview(data))
dst = MemoryFile()
state = 0
first = src.read_byte()
if first == 0x10:
raise LZOError('Invalid first stream byte 0x10.')
elif first <= 0x12:
src.seekrel(-1)
elif first <= 0x15:
state = first - 0x11
literal(state)
else:
state = 4
literal(first - 0x11)
while True:
instruction = src.read_byte()
if instruction < 0x10:
if state == 0:
length = instruction or integer() + 15
state = length + 3
if state < 4:
raise LZOError('Literal encoding is too short.')
else:
state = instruction & 0b0011
D = (instruction & 0b1100) >> 2
H = src.read_byte()
distance = (H << 2) + D + 1
if state >= 4:
distance += 0x800
length = 3
else:
length = 2
copy(distance, length)
elif instruction < 0x20:
L = instruction & 0b0111
H = instruction & 0b1000
length = L or integer() + 7
argument = src.u16()
state = argument & 3
distance = (H << 11) + (argument >> 2)
if not distance:
return dst.getbuffer()
if LZOv1 and distance & 0x803F == 0x803F and length in range(261, 265):
raise LZOError('Compressed data contains sequence that is banned in LZOv1.')
if LZOv1 and distance == 0xBFFF:
X = src.read_byte()
count = ((X << 3) | L) + 4
self.log_debug(F'Writing run of {X} zero bytes according to LZOv1.')
dst.write(B'\0' * count)
else:
copy(distance + 0x4000, length + 2)
elif instruction < 0x40:
L = instruction & 0b11111
length = L or integer() + 31
argument = src.u16()
state = argument & 3
distance = (argument >> 2) + 1
copy(distance, length + 2)
else:
if instruction < 0x80:
length = 3 + ((instruction >> 5) & 1)
else:
length = 5 + ((instruction >> 5) & 3)
H = src.read_byte()
D = (instruction & 0b11100) >> 2
state = instruction & 3
distance = (H << 3) + D + 1
copy(distance, length)
if state:
literal(state)
def __init__(self, reader: StructReader):
self.name = reader.u16()
self.descriptor = reader.u16()
def __init__(self, reader: StructReader):
self.start = reader.u16()
self.end = reader.u16()
self.handler = reader.u16()
self.catch = reader.u16()
def __init__(self, reader: StructReader):
self.access = JvAccessFlags(reader)
self.name = reader.u16()
self.descriptor = reader.u16()
self.attributes = [JvAttribute(reader, pool=self.pool) for _ in range(reader.u16())]
def __init__(self, reader: StructReader):
self.name = reader.u16()
self.data = reader.read(reader.u32())
def __init__(self, reader: StructReader):
self.bootstrap_method_attr_index = reader.u16()
self.info = reader.u16()
def __init__(self, reader: StructReader):
self.kind = JvMethodHandleRefKind(reader.read_byte())
self.reference = reader.u16()
def __init__(self, reader: StructReader):
self.name = reader.u16()
self.info = reader.u16()
def __init__(self, reader: StructReader): self.value = reader.u16() def __repr__(self): return repr(self.value)