def createMpegAudioMagic():
# ID3v1 magic
magics = [("TAG", 0)]
# ID3v2 magics
for ver_major in ID3v2.VALID_MAJOR_VERSIONS:
magic = "ID3%c\x00" % ver_major
magics.append( (magic,0) )
# MPEG frame magic
# TODO: Use longer magic: 32 bits instead of 16 bits
SYNC_BITS = 2047
for version in Frame.VERSION_NAME.iterkeys():
for layer in Frame.LAYER_NAME.iterkeys():
for crc16 in (0, 1):
magic = (SYNC_BITS << 5) | (version << 3) | (layer << 1) | crc16
magic = long2raw(magic, BIG_ENDIAN, 2)
magics.append( (magic, 0) )
return magics
def fixPNG(data):
# array -> str
data = data.tostring()
origdata = data
datalen = len(data)
data = StringIO(data)
data.seek(0)
data.write("\x89PNG\r\n\x1a\n")
index = 8
while index < (datalen-4):
data.seek(index)
size = str2long(data.read(4), BIG_ENDIAN)
chunksize = size+12
if datalen < (index+chunksize):
info("fixPNG: Skip invalid chunk at %s" % index)
break
crcofs = index+chunksize-4
data.seek(crcofs)
oldcrc = data.read(4)
data.seek(index+4)
o = data.tell()
crcdata = data.read(chunksize-8)
newcrc = long2raw(pngCRC32(crcdata), BIG_ENDIAN, 4)
data.seek(index+chunksize-4)
data.write(newcrc)
index += chunksize
data.seek(0,0)
data = data.read()
assert len(data) == len(origdata)
# str -> array
data = array('B', data)
return data
def writeInteger(self, value, signed, size_byte, endian):
if signed:
value += 1 << (size_byte*8 - 1)
raw = long2raw(value, endian, size_byte)
self.writeBytes(raw)
class PythonCompiledFile(Parser):
PARSER_TAGS = {
"id": "python",
"category": "program",
"file_ext": ("pyc", "pyo"),
"min_size": 9 * 8,
"description": "Compiled Python script (.pyc/.pyo files)"
}
endian = LITTLE_ENDIAN
# Dictionnary which associate the pyc signature (32-bit integer)
# to a Python version string (eg. "m\xf2\r\n" => "Python 2.4b1").
# This list comes from CPython source code, see "MAGIC"
# and "pyc_magic" in file Python/import.c
MAGIC = {
# Python 1.x
20121: ("1.5", 0x1050000),
# Python 2.x
50823: ("2.0", 0x2000000),
60202: ("2.1", 0x2010000),
60717: ("2.2", 0x2020000),
62011: ("2.3a0", 0x2030000),
62021: ("2.3a0", 0x2030000),
62041: ("2.4a0", 0x2040000),
62051: ("2.4a3", 0x2040000),
62061: ("2.4b1", 0x2040000),
62071: ("2.5a0", 0x2050000),
62081: ("2.5a0 (ast-branch)", 0x2050000),
62091: ("2.5a0 (with)", 0x2050000),
62092: ("2.5a0 (WITH_CLEANUP opcode)", 0x2050000),
62101: ("2.5b3", 0x2050000),
62111: ("2.5b3", 0x2050000),
62121: ("2.5c1", 0x2050000),
62131: ("2.5c2", 0x2050000),
# Python 3.x
3000: ("3.0 (3000)", 0x3000000),
3010: ("3.0 (3010)", 0x3000000),
3020: ("3.0 (3020)", 0x3000000),
3030: ("3.0 (3030)", 0x3000000),
3040: ("3.0 (3040)", 0x3000000),
3050: ("3.0 (3050)", 0x3000000),
3060: ("3.0 (3060)", 0x3000000),
3070: ("3.0 (3070)", 0x3000000),
3080: ("3.0 (3080)", 0x3000000),
3090: ("3.0 (3090)", 0x3000000),
3100: ("3.0 (3100)", 0x3000000),
3102: ("3.0 (3102)", 0x3000000),
3110: ("3.0a4", 0x3000000),
3130: ("3.0a5", 0x3000000),
3131: ("3.0a5 unicode", 0x3000000),
}
# Dictionnary which associate the pyc signature (4-byte long string)
# to a Python version string (eg. "m\xf2\r\n" => "2.4b1")
STR_MAGIC = dict( \
(long2raw(magic | (ord('\r')<<16) | (ord('\n')<<24), LITTLE_ENDIAN), value[0]) \
for magic, value in MAGIC.iteritems())
def validate(self):
signature = self.stream.readBits(0, 16, self.endian)
if signature not in self.MAGIC:
return "Unknown version (%s)" % signature
if self.stream.readBytes(2 * 8, 2) != "\r\n":
return r"Wrong signature (\r\n)"
if self.stream.readBytes(8 * 8, 1) != 'c':
return "First object bytecode is not code"
return True
def getVersion(self):
if not hasattr(self, "version"):
signature = self.stream.readBits(0, 16, self.endian)
self.version = self.MAGIC[signature][1]
return self.version
def createFields(self):
yield Enum(
Bytes(self, "signature", 4, "Python file signature and version"),
self.STR_MAGIC)
yield TimestampUnix32(self, "timestamp", "Timestamp")
yield Object(self, "content")
def writeInteger(self, value, signed, size_byte, endian):
if signed:
value += 1 << (size_byte * 8 - 1)
raw = long2raw(value, endian, size_byte)
self.writeBytes(raw)
