DeDRM_tools/DeDRM_plugin/alfcrypto.py

302 lines
9.8 KiB
Python

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# crypto library mainly by some_updates
# pbkdf2.py pbkdf2 code taken from pbkdf2.py
# pbkdf2.py Copyright © 2004 Matt Johnston <matt @ ucc asn au>
# pbkdf2.py Copyright © 2009 Daniel Holth <dholth@fastmail.fm>
# pbkdf2.py This code may be freely used and modified for any purpose.
import sys, os
import hmac
from struct import pack
import hashlib
# interface to needed routines libalfcrypto
def _load_libalfcrypto():
import ctypes
from ctypes import CDLL, byref, POINTER, c_void_p, c_char_p, c_int, c_long, \
Structure, c_ulong, create_string_buffer, addressof, string_at, cast, sizeof
pointer_size = ctypes.sizeof(ctypes.c_voidp)
name_of_lib = None
if sys.platform.startswith('darwin'):
name_of_lib = 'libalfcrypto.dylib'
elif sys.platform.startswith('win'):
if pointer_size == 4:
name_of_lib = 'alfcrypto.dll'
else:
name_of_lib = 'alfcrypto64.dll'
else:
if pointer_size == 4:
name_of_lib = 'libalfcrypto32.so'
else:
name_of_lib = 'libalfcrypto64.so'
# hard code to local location for libalfcrypto
libalfcrypto = os.path.join(sys.path[0],name_of_lib)
if not os.path.isfile(libalfcrypto):
libalfcrypto = os.path.join(sys.path[0], 'lib', name_of_lib)
if not os.path.isfile(libalfcrypto):
libalfcrypto = os.path.join('.',name_of_lib)
if not os.path.isfile(libalfcrypto):
raise Exception('libalfcrypto not found at %s' % libalfcrypto)
libalfcrypto = CDLL(libalfcrypto)
c_char_pp = POINTER(c_char_p)
c_int_p = POINTER(c_int)
def F(restype, name, argtypes):
func = getattr(libalfcrypto, name)
func.restype = restype
func.argtypes = argtypes
return func
# aes cbc decryption
#
# struct aes_key_st {
# unsigned long rd_key[4 *(AES_MAXNR + 1)];
# int rounds;
# };
#
# typedef struct aes_key_st AES_KEY;
#
# int AES_set_decrypt_key(const unsigned char *userKey, const int bits, AES_KEY *key);
#
#
# void AES_cbc_encrypt(const unsigned char *in, unsigned char *out,
# const unsigned long length, const AES_KEY *key,
# unsigned char *ivec, const int enc);
AES_MAXNR = 14
class AES_KEY(Structure):
_fields_ = [('rd_key', c_long * (4 * (AES_MAXNR + 1))), ('rounds', c_int)]
AES_KEY_p = POINTER(AES_KEY)
AES_cbc_encrypt = F(None, 'AES_cbc_encrypt',[c_char_p, c_char_p, c_ulong, AES_KEY_p, c_char_p, c_int])
AES_set_decrypt_key = F(c_int, 'AES_set_decrypt_key',[c_char_p, c_int, AES_KEY_p])
# Pukall 1 Cipher
# unsigned char *PC1(const unsigned char *key, unsigned int klen, const unsigned char *src,
# unsigned char *dest, unsigned int len, int decryption);
PC1 = F(c_char_p, 'PC1', [c_char_p, c_ulong, c_char_p, c_char_p, c_ulong, c_ulong])
# Topaz Encryption
# typedef struct _TpzCtx {
# unsigned int v[2];
# } TpzCtx;
#
# void topazCryptoInit(TpzCtx *ctx, const unsigned char *key, int klen);
# void topazCryptoDecrypt(const TpzCtx *ctx, const unsigned char *in, unsigned char *out, int len);
class TPZ_CTX(Structure):
_fields_ = [('v', c_long * 2)]
TPZ_CTX_p = POINTER(TPZ_CTX)
topazCryptoInit = F(None, 'topazCryptoInit', [TPZ_CTX_p, c_char_p, c_ulong])
topazCryptoDecrypt = F(None, 'topazCryptoDecrypt', [TPZ_CTX_p, c_char_p, c_char_p, c_ulong])
class AES_CBC(object):
def __init__(self):
self._blocksize = 0
self._keyctx = None
self._iv = 0
def set_decrypt_key(self, userkey, iv):
self._blocksize = len(userkey)
if (self._blocksize != 16) and (self._blocksize != 24) and (self._blocksize != 32) :
raise Exception('AES CBC improper key used')
return
keyctx = self._keyctx = AES_KEY()
self._iv = iv
rv = AES_set_decrypt_key(userkey, len(userkey) * 8, keyctx)
if rv < 0:
raise Exception('Failed to initialize AES CBC key')
def decrypt(self, data):
out = create_string_buffer(len(data))
mutable_iv = create_string_buffer(self._iv, len(self._iv))
rv = AES_cbc_encrypt(data, out, len(data), self._keyctx, mutable_iv, 0)
if rv == 0:
raise Exception('AES CBC decryption failed')
return out.raw
class Pukall_Cipher(object):
def __init__(self):
self.key = None
def PC1(self, key, src, decryption=True):
self.key = key
out = create_string_buffer(len(src))
de = 0
if decryption:
de = 1
rv = PC1(key, len(key), src, out, len(src), de)
return out.raw
class Topaz_Cipher(object):
def __init__(self):
self._ctx = None
def ctx_init(self, key):
tpz_ctx = self._ctx = TPZ_CTX()
topazCryptoInit(tpz_ctx, key, len(key))
return tpz_ctx
def decrypt(self, data, ctx=None):
if ctx == None:
ctx = self._ctx
out = create_string_buffer(len(data))
topazCryptoDecrypt(ctx, data, out, len(data))
return out.raw
print("Using Library AlfCrypto DLL/DYLIB/SO")
return (AES_CBC, Pukall_Cipher, Topaz_Cipher)
def _load_python_alfcrypto():
import aescbc
class Pukall_Cipher(object):
def __init__(self):
self.key = None
def PC1(self, key, src, decryption=True):
sum1 = 0;
sum2 = 0;
keyXorVal = 0;
if len(key)!=16:
raise Exception('Pukall_Cipher: Bad key length.')
wkey = []
for i in range(8):
wkey.append(ord(key[i*2])<<8 | ord(key[i*2+1]))
dst = ""
for i in range(len(src)):
temp1 = 0;
byteXorVal = 0;
for j in range(8):
temp1 ^= wkey[j]
sum2 = (sum2+j)*20021 + sum1
sum1 = (temp1*346)&0xFFFF
sum2 = (sum2+sum1)&0xFFFF
temp1 = (temp1*20021+1)&0xFFFF
byteXorVal ^= temp1 ^ sum2
curByte = ord(src[i])
if not decryption:
keyXorVal = curByte * 257;
curByte = ((curByte ^ (byteXorVal >> 8)) ^ byteXorVal) & 0xFF
if decryption:
keyXorVal = curByte * 257;
for j in range(8):
wkey[j] ^= keyXorVal;
dst+=chr(curByte)
return dst
class Topaz_Cipher(object):
def __init__(self):
self._ctx = None
def ctx_init(self, key):
ctx1 = 0x0CAFFE19E
for keyChar in key:
keyByte = ord(keyChar)
ctx2 = ctx1
ctx1 = ((((ctx1 >>2) * (ctx1 >>7))&0xFFFFFFFF) ^ (keyByte * keyByte * 0x0F902007)& 0xFFFFFFFF )
self._ctx = [ctx1, ctx2]
return [ctx1,ctx2]
def decrypt(self, data, ctx=None):
if ctx == None:
ctx = self._ctx
ctx1 = ctx[0]
ctx2 = ctx[1]
plainText = ""
for dataChar in data:
dataByte = ord(dataChar)
m = (dataByte ^ ((ctx1 >> 3) &0xFF) ^ ((ctx2<<3) & 0xFF)) &0xFF
ctx2 = ctx1
ctx1 = (((ctx1 >> 2) * (ctx1 >> 7)) &0xFFFFFFFF) ^((m * m * 0x0F902007) &0xFFFFFFFF)
plainText += chr(m)
return plainText
class AES_CBC(object):
def __init__(self):
self._key = None
self._iv = None
self.aes = None
def set_decrypt_key(self, userkey, iv):
self._key = userkey
self._iv = iv
self.aes = aescbc.AES_CBC(userkey, aescbc.noPadding(), len(userkey))
def decrypt(self, data):
iv = self._iv
cleartext = self.aes.decrypt(iv + data)
return cleartext
print("Using Library AlfCrypto Python")
return (AES_CBC, Pukall_Cipher, Topaz_Cipher)
def _load_crypto():
AES_CBC = Pukall_Cipher = Topaz_Cipher = None
cryptolist = (_load_libalfcrypto, _load_python_alfcrypto)
for loader in cryptolist:
try:
AES_CBC, Pukall_Cipher, Topaz_Cipher = loader()
break
except (ImportError, Exception):
pass
return AES_CBC, Pukall_Cipher, Topaz_Cipher
AES_CBC, Pukall_Cipher, Topaz_Cipher = _load_crypto()
class KeyIVGen(object):
# this only exists in openssl so we will use pure python implementation instead
# PKCS5_PBKDF2_HMAC_SHA1 = F(c_int, 'PKCS5_PBKDF2_HMAC_SHA1',
# [c_char_p, c_ulong, c_char_p, c_ulong, c_ulong, c_ulong, c_char_p])
def pbkdf2(self, passwd, salt, iter, keylen):
def xorstr( a, b ):
if len(a) != len(b):
raise Exception("xorstr(): lengths differ")
return ''.join((chr(ord(x)^ord(y)) for x, y in zip(a, b)))
def prf( h, data ):
hm = h.copy()
hm.update( data )
return hm.digest()
def pbkdf2_F( h, salt, itercount, blocknum ):
U = prf( h, salt + pack('>i',blocknum ) )
T = U
for i in range(2, itercount+1):
U = prf( h, U )
T = xorstr( T, U )
return T
sha = hashlib.sha1
digest_size = sha().digest_size
# l - number of output blocks to produce
l = keylen / digest_size
if keylen % digest_size != 0:
l += 1
h = hmac.new( passwd, None, sha )
T = ""
for i in range(1, l+1):
T += pbkdf2_F( h, salt, iter, i )
return T[0: keylen]