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# Pure python AES128 implementation
# SciresM, 2017
from struct import unpack as up, pack as pk
def sxor(s1, s2):
'''Xors two strings.'''
assert(len(s1) == len(s2))
return ''.join([chr(ord(x) ^ ord(y)) for x,y in zip(s1, s2)])
class AESCBC:
'''Class for performing AES CBC cipher operations.'''
def __init__(self, key, iv):
self.aes = AESECB(key)
if len(iv) != self.aes.block_size:
raise ValueError('IV must be of size %X!' % self.aes.block_size)
self.iv = iv
def encrypt(self, data, iv=None):
'''Encrypts some data in CBC mode.'''
if iv is None:
iv = self.iv
out = ''
while data:
encb = self.aes.encrypt_block_ecb(sxor(data[:0x10], iv))
out += encb
iv = encb
data = data[0x10:]
return out
def decrypt(self, data, iv=None):
'''Decrypts some data in CBC mode.'''
if len(data) % self.aes.block_size:
raise ValueError('Data is not aligned to block size!')
if iv is None:
iv = self.iv
out = ''
while data:
decb = sxor(self.aes.decrypt_block_ecb(data[:0x10]), iv)
out += decb
iv = data[:0x10]
data = data[0x10:]
return out
def set_iv(self, iv):
if len(iv) != self.aes.block_size:
raise ValueError('IV must be of size %X!' % self.aes.block_size)
self.iv = iv
class AESCTR:
'''Class for performing AES CTR cipher operations.'''
def __init__(self, key, ctr):
self.aes = AESECB(key)
if len(ctr) != self.aes.block_size:
raise ValueError('CTR must be of size %X!' % self.aes.block_size)
self.ctr = int(ctr.encode('hex'), 0x10)
def encrypt(self, data, ctr=None):
'''Encrypts some data in CTR mode.'''
if ctr is None:
ctr = self.ctr
elif type(ctr) is not int:
ctr = int(ctr.encode('hex'), 16)
out = ''
ln = len(data)
while ln:
xorpad = self.aes.encrypt_block_ecb(('%032X' % ctr).decode('hex'))
l = min(0x10, ln)
out += sxor(data[:l], xorpad[:l])
data = data[l:]
ln -= l
ctr += 1
return out
def decrypt(self, data, ctr=None):
'''Decrypts some data in CTR mode.
This is identical to encryption, because CTR mode is symmetric.
'''
return self.encrypt(data, ctr)
def set_ctr(self, ctr):
if len(ctr) != self.aes.block_size:
raise ValueError('CTR must be of size %X!' % self.aes.block_size)
self.ctr = int(ctr, 0x10)
class AESXTS:
'''Class for performing AES XTS cipher operations'''
def __init__(self, keys, sector=0):
if not(type(keys) is tuple and len(keys) == 2):
raise TypeError('XTS mode requires a tuple of two keys.')
self.K1 = AESECB(keys[0])
self.K2 = AESECB(keys[1])
self.keys = keys
self.sector = sector
self.block_size = self.K1.block_size
def encrypt(self, data, sector=None):
if sector is None:
sector = self.sector
if len(data) % self.block_size:
raise ValueError('Data is not aligned to block size!')
out = ''
while data:
tweak = self.get_tweak(sector)
out += self.encrypt_sector(data[:0x200], tweak)
data = data[0x200:]
sector += 1
return out
def encrypt_sector(self, data, tweak):
if len(data) % self.block_size:
raise ValueError('Data is not aligned to block size!')
out = ''
tweak = self.K2.encrypt(('%032X' % tweak).decode('hex'))
while data:
out += sxor(tweak, self.K1.encrypt_block_ecb(sxor(data[:0x10], tweak)))
_t = int(tweak[::-1].encode('hex'), 16)
_t <<= 1
if _t & (1 << 128):
_t ^= ((1 << 128) | (0x87))
tweak = ('%032X' % _t).decode('hex')[::-1]
data = data[0x10:]
return out
def decrypt(self, data, sector=None):
if sector is None:
sector = self.sector
if len(data) % self.block_size:
raise ValueError('Data is not aligned to block size!')
out = ''
while data:
tweak = self.get_tweak(sector)
out += self.decrypt_sector(data[:0x200], tweak)
data = data[0x200:]
sector += 1
return out
def decrypt_sector(self, data, tweak):
if len(data) % self.block_size:
raise ValueError('Data is not aligned to block size!')
out = ''
tweak = self.K2.encrypt(('%032X' % tweak).decode('hex'))
while data:
out += sxor(tweak, self.K1.decrypt_block_ecb(sxor(data[:0x10], tweak)))
_t = int(tweak[::-1].encode('hex'), 16)
_t <<= 1
if _t & (1 << 128):
_t ^= ((1 << 128) | (0x87))
tweak = ('%032X' % _t).decode('hex')[::-1]
data = data[0x10:]
return out
def get_tweak(self, sector=None):
'''Gets tweak for use in XEX.'''
if sector is None:
sector = self.sector
tweak = 0
for i in xrange(self.block_size):
tweak |= (sector & 0xFF) << ((self.block_size - i - 1) * 8)
sector >>= 8
return tweak
def set_sector(self, sector):
self.sector = sector
class AESXTSN:
'''Class for performing Nintendo AES XTS cipher operations'''
def __init__(self, keys, sector_size=0x200, sector=0):
if not(type(keys) is tuple and len(keys) == 2):
raise TypeError('XTS mode requires a tuple of two keys.')
self.K1 = AESECB(keys[0])
self.K2 = AESECB(keys[1])
self.keys = keys
self.sector = sector
self.sector_size = sector_size
self.block_size = self.K1.block_size
def encrypt(self, data, sector=None):
if sector is None:
sector = self.sector
if len(data) % self.block_size:
raise ValueError('Data is not aligned to block size!')
out = ''
while data:
tweak = self.get_tweak(sector)
out += self.encrypt_sector(data[:self.sector_size], tweak)
data = data[self.sector_size:]
sector += 1
return out
def encrypt_sector(self, data, tweak):
if len(data) % self.block_size:
raise ValueError('Data is not aligned to block size!')
out = ''
tweak = self.K2.encrypt(('%032X' % tweak).decode('hex'))
while data:
out += sxor(tweak, self.K1.encrypt_block_ecb(sxor(data[:0x10], tweak)))
_t = int(tweak[::-1].encode('hex'), 16)
_t <<= 1
if _t & (1 << 128):
_t ^= ((1 << 128) | (0x87))
tweak = ('%032X' % _t).decode('hex')[::-1]
data = data[0x10:]
return out
def decrypt(self, data, sector=None):
if sector is None:
sector = self.sector
if len(data) % self.block_size:
raise ValueError('Data is not aligned to block size!')
out = ''
while data:
tweak = self.get_tweak(sector)
out += self.decrypt_sector(data[:self.sector_size], tweak)
data = data[self.sector_size:]
sector += 1
return out
def decrypt_sector(self, data, tweak):
if len(data) % self.block_size:
raise ValueError('Data is not aligned to block size!')
out = ''
tweak = self.K2.encrypt(('%032X' % tweak).decode('hex'))
while data:
out += sxor(tweak, self.K1.decrypt_block_ecb(sxor(data[:0x10], tweak)))
_t = int(tweak[::-1].encode('hex'), 16)
_t <<= 1
if _t & (1 << 128):
_t ^= ((1 << 128) | (0x87))
tweak = ('%032X' % _t).decode('hex')[::-1]
data = data[0x10:]
return out
def get_tweak(self, sector=None):
'''Gets tweak for use in XEX.'''
if sector is None:
sector = self.sector
tweak = 0
for i in xrange(self.block_size):
tweak |= (sector & 0xFF) << (i * 8)
sector >>= 8
return tweak
def set_sector(self, sector):
self.sector = sector
def set_sector_size(self, sector_size):
self.sector_size = sector_size
class AESECB:
'''Class for performing AES ECB cipher operations.'''
# Constants for performing AES operations -- rcon table, S boxes.
rcon_table = [0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d]
sbox_enc = [0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16]
sbox_dec = [0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d]
mult_1_table = range(0x100)
mult_2_table = [0x00,0x02,0x04,0x06,0x08,0x0a,0x0c,0x0e,0x10,0x12,0x14,0x16,0x18,0x1a,0x1c,0x1e,0x20,0x22,0x24,0x26,0x28,0x2a,0x2c,0x2e,0x30,0x32,0x34,0x36,0x38,0x3a,0x3c,0x3e,0x40,0x42,0x44,0x46,0x48,0x4a,0x4c,0x4e,0x50,0x52,0x54,0x56,0x58,0x5a,0x5c,0x5e,0x60,0x62,0x64,0x66,0x68,0x6a,0x6c,0x6e,0x70,0x72,0x74,0x76,0x78,0x7a,0x7c,0x7e,0x80,0x82,0x84,0x86,0x88,0x8a,0x8c,0x8e,0x90,0x92,0x94,0x96,0x98,0x9a,0x9c,0x9e,0xa0,0xa2,0xa4,0xa6,0xa8,0xaa,0xac,0xae,0xb0,0xb2,0xb4,0xb6,0xb8,0xba,0xbc,0xbe,0xc0,0xc2,0xc4,0xc6,0xc8,0xca,0xcc,0xce,0xd0,0xd2,0xd4,0xd6,0xd8,0xda,0xdc,0xde,0xe0,0xe2,0xe4,0xe6,0xe8,0xea,0xec,0xee,0xf0,0xf2,0xf4,0xf6,0xf8,0xfa,0xfc,0xfe,0x1b,0x19,0x1f,0x1d,0x13,0x11,0x17,0x15,0x0b,0x09,0x0f,0x0d,0x03,0x01,0x07,0x05,0x3b,0x39,0x3f,0x3d,0x33,0x31,0x37,0x35,0x2b,0x29,0x2f,0x2d,0x23,0x21,0x27,0x25,0x5b,0x59,0x5f,0x5d,0x53,0x51,0x57,0x55,0x4b,0x49,0x4f,0x4d,0x43,0x41,0x47,0x45,0x7b,0x79,0x7f,0x7d,0x73,0x71,0x77,0x75,0x6b,0x69,0x6f,0x6d,0x63,0x61,0x67,0x65,0x9b,0x99,0x9f,0x9d,0x93,0x91,0x97,0x95,0x8b,0x89,0x8f,0x8d,0x83,0x81,0x87,0x85,0xbb,0xb9,0xbf,0xbd,0xb3,0xb1,0xb7,0xb5,0xab,0xa9,0xaf,0xad,0xa3,0xa1,0xa7,0xa5,0xdb,0xd9,0xdf,0xdd,0xd3,0xd1,0xd7,0xd5,0xcb,0xc9,0xcf,0xcd,0xc3,0xc1,0xc7,0xc5,0xfb,0xf9,0xff,0xfd,0xf3,0xf1,0xf7,0xf5,0xeb,0xe9,0xef,0xed,0xe3,0xe1,0xe7,0xe5]
mult_3_table = [0x00,0x03,0x06,0x05,0x0c,0x0f,0x0a,0x09,0x18,0x1b,0x1e,0x1d,0x14,0x17,0x12,0x11,0x30,0x33,0x36,0x35,0x3c,0x3f,0x3a,0x39,0x28,0x2b,0x2e,0x2d,0x24,0x27,0x22,0x21,0x60,0x63,0x66,0x65,0x6c,0x6f,0x6a,0x69,0x78,0x7b,0x7e,0x7d,0x74,0x77,0x72,0x71,0x50,0x53,0x56,0x55,0x5c,0x5f,0x5a,0x59,0x48,0x4b,0x4e,0x4d,0x44,0x47,0x42,0x41,0xc0,0xc3,0xc6,0xc5,0xcc,0xcf,0xca,0xc9,0xd8,0xdb,0xde,0xdd,0xd4,0xd7,0xd2,0xd1,0xf0,0xf3,0xf6,0xf5,0xfc,0xff,0xfa,0xf9,0xe8,0xeb,0xee,0xed,0xe4,0xe7,0xe2,0xe1,0xa0,0xa3,0xa6,0xa5,0xac,0xaf,0xaa,0xa9,0xb8,0xbb,0xbe,0xbd,0xb4,0xb7,0xb2,0xb1,0x90,0x93,0x96,0x95,0x9c,0x9f,0x9a,0x99,0x88,0x8b,0x8e,0x8d,0x84,0x87,0x82,0x81,0x9b,0x98,0x9d,0x9e,0x97,0x94,0x91,0x92,0x83,0x80,0x85,0x86,0x8f,0x8c,0x89,0x8a,0xab,0xa8,0xad,0xae,0xa7,0xa4,0xa1,0xa2,0xb3,0xb0,0xb5,0xb6,0xbf,0xbc,0xb9,0xba,0xfb,0xf8,0xfd,0xfe,0xf7,0xf4,0xf1,0xf2,0xe3,0xe0,0xe5,0xe6,0xef,0xec,0xe9,0xea,0xcb,0xc8,0xcd,0xce,0xc7,0xc4,0xc1,0xc2,0xd3,0xd0,0xd5,0xd6,0xdf,0xdc,0xd9,0xda,0x5b,0x58,0x5d,0x5e,0x57,0x54,0x51,0x52,0x43,0x40,0x45,0x46,0x4f,0x4c,0x49,0x4a,0x6b,0x68,0x6d,0x6e,0x67,0x64,0x61,0x62,0x73,0x70,0x75,0x76,0x7f,0x7c,0x79,0x7a,0x3b,0x38,0x3d,0x3e,0x37,0x34,0x31,0x32,0x23,0x20,0x25,0x26,0x2f,0x2c,0x29,0x2a,0x0b,0x08,0x0d,0x0e,0x07,0x04,0x01,0x02,0x13,0x10,0x15,0x16,0x1f,0x1c,0x19,0x1a]
mult_9_table = [0x00,0x09,0x12,0x1b,0x24,0x2d,0x36,0x3f,0x48,0x41,0x5a,0x53,0x6c,0x65,0x7e,0x77,0x90,0x99,0x82,0x8b,0xb4,0xbd,0xa6,0xaf,0xd8,0xd1,0xca,0xc3,0xfc,0xf5,0xee,0xe7,0x3b,0x32,0x29,0x20,0x1f,0x16,0x0d,0x04,0x73,0x7a,0x61,0x68,0x57,0x5e,0x45,0x4c,0xab,0xa2,0xb9,0xb0,0x8f,0x86,0x9d,0x94,0xe3,0xea,0xf1,0xf8,0xc7,0xce,0xd5,0xdc,0x76,0x7f,0x64,0x6d,0x52,0x5b,0x40,0x49,0x3e,0x37,0x2c,0x25,0x1a,0x13,0x08,0x01,0xe6,0xef,0xf4,0xfd,0xc2,0xcb,0xd0,0xd9,0xae,0xa7,0xbc,0xb5,0x8a,0x83,0x98,0x91,0x4d,0x44,0x5f,0x56,0x69,0x60,0x7b,0x72,0x05,0x0c,0x17,0x1e,0x21,0x28,0x33,0x3a,0xdd,0xd4,0xcf,0xc6,0xf9,0xf0,0xeb,0xe2,0x95,0x9c,0x87,0x8e,0xb1,0xb8,0xa3,0xaa,0xec,0xe5,0xfe,0xf7,0xc8,0xc1,0xda,0xd3,0xa4,0xad,0xb6,0xbf,0x80,0x89,0x92,0x9b,0x7c,0x75,0x6e,0x67,0x58,0x51,0x4a,0x43,0x34,0x3d,0x26,0x2f,0x10,0x19,0x02,0x0b,0xd7,0xde,0xc5,0xcc,0xf3,0xfa,0xe1,0xe8,0x9f,0x96,0x8d,0x84,0xbb,0xb2,0xa9,0xa0,0x47,0x4e,0x55,0x5c,0x63,0x6a,0x71,0x78,0x0f,0x06,0x1d,0x14,0x2b,0x22,0x39,0x30,0x9a,0x93,0x88,0x81,0xbe,0xb7,0xac,0xa5,0xd2,0xdb,0xc0,0xc9,0xf6,0xff,0xe4,0xed,0x0a,0x03,0x18,0x11,0x2e,0x27,0x3c,0x35,0x42,0x4b,0x50,0x59,0x66,0x6f,0x74,0x7d,0xa1,0xa8,0xb3,0xba,0x85,0x8c,0x97,0x9e,0xe9,0xe0,0xfb,0xf2,0xcd,0xc4,0xdf,0xd6,0x31,0x38,0x23,0x2a,0x15,0x1c,0x07,0x0e,0x79,0x70,0x6b,0x62,0x5d,0x54,0x4f,0x46]
mult_B_table = [0x00,0x0b,0x16,0x1d,0x2c,0x27,0x3a,0x31,0x58,0x53,0x4e,0x45,0x74,0x7f,0x62,0x69,0xb0,0xbb,0xa6,0xad,0x9c,0x97,0x8a,0x81,0xe8,0xe3,0xfe,0xf5,0xc4,0xcf,0xd2,0xd9,0x7b,0x70,0x6d,0x66,0x57,0x5c,0x41,0x4a,0x23,0x28,0x35,0x3e,0x0f,0x04,0x19,0x12,0xcb,0xc0,0xdd,0xd6,0xe7,0xec,0xf1,0xfa,0x93,0x98,0x85,0x8e,0xbf,0xb4,0xa9,0xa2,0xf6,0xfd,0xe0,0xeb,0xda,0xd1,0xcc,0xc7,0xae,0xa5,0xb8,0xb3,0x82,0x89,0x94,0x9f,0x46,0x4d,0x50,0x5b,0x6a,0x61,0x7c,0x77,0x1e,0x15,0x08,0x03,0x32,0x39,0x24,0x2f,0x8d,0x86,0x9b,0x90,0xa1,0xaa,0xb7,0xbc,0xd5,0xde,0xc3,0xc8,0xf9,0xf2,0xef,0xe4,0x3d,0x36,0x2b,0x20,0x11,0x1a,0x07,0x0c,0x65,0x6e,0x73,0x78,0x49,0x42,0x5f,0x54,0xf7,0xfc,0xe1,0xea,0xdb,0xd0,0xcd,0xc6,0xaf,0xa4,0xb9,0xb2,0x83,0x88,0x95,0x9e,0x47,0x4c,0x51,0x5a,0x6b,0x60,0x7d,0x76,0x1f,0x14,0x09,0x02,0x33,0x38,0x25,0x2e,0x8c,0x87,0x9a,0x91,0xa0,0xab,0xb6,0xbd,0xd4,0xdf,0xc2,0xc9,0xf8,0xf3,0xee,0xe5,0x3c,0x37,0x2a,0x21,0x10,0x1b,0x06,0x0d,0x64,0x6f,0x72,0x79,0x48,0x43,0x5e,0x55,0x01,0x0a,0x17,0x1c,0x2d,0x26,0x3b,0x30,0x59,0x52,0x4f,0x44,0x75,0x7e,0x63,0x68,0xb1,0xba,0xa7,0xac,0x9d,0x96,0x8b,0x80,0xe9,0xe2,0xff,0xf4,0xc5,0xce,0xd3,0xd8,0x7a,0x71,0x6c,0x67,0x56,0x5d,0x40,0x4b,0x22,0x29,0x34,0x3f,0x0e,0x05,0x18,0x13,0xca,0xc1,0xdc,0xd7,0xe6,0xed,0xf0,0xfb,0x92,0x99,0x84,0x8f,0xbe,0xb5,0xa8,0xa3]
mult_D_table = [0x00,0x0d,0x1a,0x17,0x34,0x39,0x2e,0x23,0x68,0x65,0x72,0x7f,0x5c,0x51,0x46,0x4b,0xd0,0xdd,0xca,0xc7,0xe4,0xe9,0xfe,0xf3,0xb8,0xb5,0xa2,0xaf,0x8c,0x81,0x96,0x9b,0xbb,0xb6,0xa1,0xac,0x8f,0x82,0x95,0x98,0xd3,0xde,0xc9,0xc4,0xe7,0xea,0xfd,0xf0,0x6b,0x66,0x71,0x7c,0x5f,0x52,0x45,0x48,0x03,0x0e,0x19,0x14,0x37,0x3a,0x2d,0x20,0x6d,0x60,0x77,0x7a,0x59,0x54,0x43,0x4e,0x05,0x08,0x1f,0x12,0x31,0x3c,0x2b,0x26,0xbd,0xb0,0xa7,0xaa,0x89,0x84,0x93,0x9e,0xd5,0xd8,0xcf,0xc2,0xe1,0xec,0xfb,0xf6,0xd6,0xdb,0xcc,0xc1,0xe2,0xef,0xf8,0xf5,0xbe,0xb3,0xa4,0xa9,0x8a,0x87,0x90,0x9d,0x06,0x0b,0x1c,0x11,0x32,0x3f,0x28,0x25,0x6e,0x63,0x74,0x79,0x5a,0x57,0x40,0x4d,0xda,0xd7,0xc0,0xcd,0xee,0xe3,0xf4,0xf9,0xb2,0xbf,0xa8,0xa5,0x86,0x8b,0x9c,0x91,0x0a,0x07,0x10,0x1d,0x3e,0x33,0x24,0x29,0x62,0x6f,0x78,0x75,0x56,0x5b,0x4c,0x41,0x61,0x6c,0x7b,0x76,0x55,0x58,0x4f,0x42,0x09,0x04,0x13,0x1e,0x3d,0x30,0x27,0x2a,0xb1,0xbc,0xab,0xa6,0x85,0x88,0x9f,0x92,0xd9,0xd4,0xc3,0xce,0xed,0xe0,0xf7,0xfa,0xb7,0xba,0xad,0xa0,0x83,0x8e,0x99,0x94,0xdf,0xd2,0xc5,0xc8,0xeb,0xe6,0xf1,0xfc,0x67,0x6a,0x7d,0x70,0x53,0x5e,0x49,0x44,0x0f,0x02,0x15,0x18,0x3b,0x36,0x21,0x2c,0x0c,0x01,0x16,0x1b,0x38,0x35,0x22,0x2f,0x64,0x69,0x7e,0x73,0x50,0x5d,0x4a,0x47,0xdc,0xd1,0xc6,0xcb,0xe8,0xe5,0xf2,0xff,0xb4,0xb9,0xae,0xa3,0x80,0x8d,0x9a,0x97]
mult_E_table = [0x00,0x0e,0x1c,0x12,0x38,0x36,0x24,0x2a,0x70,0x7e,0x6c,0x62,0x48,0x46,0x54,0x5a,0xe0,0xee,0xfc,0xf2,0xd8,0xd6,0xc4,0xca,0x90,0x9e,0x8c,0x82,0xa8,0xa6,0xb4,0xba,0xdb,0xd5,0xc7,0xc9,0xe3,0xed,0xff,0xf1,0xab,0xa5,0xb7,0xb9,0x93,0x9d,0x8f,0x81,0x3b,0x35,0x27,0x29,0x03,0x0d,0x1f,0x11,0x4b,0x45,0x57,0x59,0x73,0x7d,0x6f,0x61,0xad,0xa3,0xb1,0xbf,0x95,0x9b,0x89,0x87,0xdd,0xd3,0xc1,0xcf,0xe5,0xeb,0xf9,0xf7,0x4d,0x43,0x51,0x5f,0x75,0x7b,0x69,0x67,0x3d,0x33,0x21,0x2f,0x05,0x0b,0x19,0x17,0x76,0x78,0x6a,0x64,0x4e,0x40,0x52,0x5c,0x06,0x08,0x1a,0x14,0x3e,0x30,0x22,0x2c,0x96,0x98,0x8a,0x84,0xae,0xa0,0xb2,0xbc,0xe6,0xe8,0xfa,0xf4,0xde,0xd0,0xc2,0xcc,0x41,0x4f,0x5d,0x53,0x79,0x77,0x65,0x6b,0x31,0x3f,0x2d,0x23,0x09,0x07,0x15,0x1b,0xa1,0xaf,0xbd,0xb3,0x99,0x97,0x85,0x8b,0xd1,0xdf,0xcd,0xc3,0xe9,0xe7,0xf5,0xfb,0x9a,0x94,0x86,0x88,0xa2,0xac,0xbe,0xb0,0xea,0xe4,0xf6,0xf8,0xd2,0xdc,0xce,0xc0,0x7a,0x74,0x66,0x68,0x42,0x4c,0x5e,0x50,0x0a,0x04,0x16,0x18,0x32,0x3c,0x2e,0x20,0xec,0xe2,0xf0,0xfe,0xd4,0xda,0xc8,0xc6,0x9c,0x92,0x80,0x8e,0xa4,0xaa,0xb8,0xb6,0x0c,0x02,0x10,0x1e,0x34,0x3a,0x28,0x26,0x7c,0x72,0x60,0x6e,0x44,0x4a,0x58,0x56,0x37,0x39,0x2b,0x25,0x0f,0x01,0x13,0x1d,0x47,0x49,0x5b,0x55,0x7f,0x71,0x63,0x6d,0xd7,0xd9,0xcb,0xc5,0xef,0xe1,0xf3,0xfd,0xa7,0xa9,0xbb,0xb5,0x9f,0x91,0x83,0x8d]
mult_table = [None,mult_1_table,mult_2_table,mult_3_table,None,None,None,None,None,mult_9_table,None,mult_B_table,None,mult_D_table,mult_E_table,None]
mix_mults = [[0x2,0x3,0x1,0x1],[0x1,0x2,0x3,0x1],[0x1,0x1,0x2,0x3],[0x3,0x1,0x1,0x2]]
unmix_mults = [[0xE,0xB,0xD,0x9],[0x9,0xE,0xB,0xD],[0xD,0x9,0xE,0xB],[0xB,0xD,0x9,0xE]]
def __init__(self, key):
self.block_size, self.num_rounds = 0x10, 10 # 128-bit AES
if len(key) != self.block_size:
raise ValueError('Key must be of size %X!' % self.block_size)
self.keys = [list(up('>IIII', key))]
for i in xrange(1, self.num_rounds+1):
new_key = [self.key_schedule_core(self.keys[i-1][3], i) ^ self.keys[i-1][0]]
for j in range(1, 4):
new_key.append(self.keys[i-1][j] ^ new_key[j-1])
self.keys.append(new_key)
def encrypt(self, data):
'''Encrypts some data in ECB mode.'''
out = ''
while data:
out += self.encrypt_block_ecb(data[:0x10])
data = data[0x10:]
return out
def decrypt(self, data):
'''Decrypts some data in EBC mode.'''
if len(data) % self.block_size:
raise ValueError('Data is not aligned to block size!')
out = ''
while data:
out += self.decrypt_block_ecb(data[:0x10])
data = data[0x10:]
return out
def encrypt_block_ecb(self, block):
words = list(up('>IIII', self.pad_block(block)))
for i in xrange(len(words)):
words[i] ^= self.keys[0][i]
for rnd in xrange(1, self.num_rounds + 1):
for i in xrange(len(words)):
words[i] = self.send_through_sbox(words[i], self.sbox_enc)
words = self.shift_columns(words)
if rnd != self.num_rounds:
words = self.mix_columns(words)
for i in xrange(len(words)):
words[i] ^= self.keys[rnd][i]
return pk('>IIII', words[0], words[1], words[2], words[3])
def decrypt_block_ecb(self, block):
assert(len(block) == self.block_size)
words = list(up('>IIII', block))
for rnd in xrange(self.num_rounds, 0, -1):
for i in xrange(len(words)):
words[i] ^= self.keys[rnd][i]
if rnd != self.num_rounds:
words = self.unmix_columns(words)
words = self.unshift_columns(words)
for i in xrange(len(words)):
words[i] = self.send_through_sbox(words[i], self.sbox_dec)
for i in xrange(len(words)):
words[i] ^= self.keys[0][i]
return pk('>IIII', words[0], words[1], words[2], words[3])
# Helper functions
def rotate_op(self, word):
'''Rotate operation'''
return ((word & 0xFFFFFF) << 8) | ((word & 0xFF000000) >> 24)
def rcon_op(self, i):
'''Rcon operation'''
assert(0 <= i and i < len(self.rcon_table))
return self.rcon_table[i]
def send_through_sbox(self, word, sbox=sbox_enc):
'''Sends a 32-bit word through an sbox.'''
return (sbox[((word & (0xFF << 0x18)) >> 0x18)] << 0x18) | \
(sbox[((word & (0xFF << 0x10)) >> 0x10)] << 0x10) | \
(sbox[((word & (0xFF << 0x08)) >> 0x08)] << 0x08) | \
(sbox[((word & (0xFF << 0x00)) >> 0x00)] << 0x00)
def shift_columns(self, words):
'''Performs column shifting for AES.'''
new_words = []
new_words.append((words[0] & 0xFF000000) | (words[1] & 0xFF0000) | (words[2] & 0xFF00) | (words[3] & 0xFF))
new_words.append((words[1] & 0xFF000000) | (words[2] & 0xFF0000) | (words[3] & 0xFF00) | (words[0] & 0xFF))
new_words.append((words[2] & 0xFF000000) | (words[3] & 0xFF0000) | (words[0] & 0xFF00) | (words[1] & 0xFF))
new_words.append((words[3] & 0xFF000000) | (words[0] & 0xFF0000) | (words[1] & 0xFF00) | (words[2] & 0xFF))
return new_words
def unshift_columns(self, words):
'''Performs column unshifting for AES.'''
new_words = []
new_words.append((words[0] & 0xFF000000) | (words[3] & 0xFF0000) | (words[2] & 0xFF00) | (words[1] & 0xFF))
new_words.append((words[1] & 0xFF000000) | (words[0] & 0xFF0000) | (words[3] & 0xFF00) | (words[2] & 0xFF))
new_words.append((words[2] & 0xFF000000) | (words[1] & 0xFF0000) | (words[0] & 0xFF00) | (words[3] & 0xFF))
new_words.append((words[3] & 0xFF000000) | (words[2] & 0xFF0000) | (words[1] & 0xFF00) | (words[0] & 0xFF))
return new_words
def mix_columns(self, words):
'''Performs column mixing for 128-bit AES'''
return [self.mix_column(words[0], self.mix_mults), self.mix_column(words[1], self.mix_mults), \
self.mix_column(words[2], self.mix_mults), self.mix_column(words[3], self.mix_mults)]
def unmix_columns(self, words):
'''Performs column unmixing for 128-bit AES'''
return [self.mix_column(words[0], self.unmix_mults), self.mix_column(words[1], self.unmix_mults), \
self.mix_column(words[2], self.unmix_mults), self.mix_column(words[3], self.unmix_mults)]
def mix_column(self, word, mults):
'''Performs column mixing on a single column'''
return ((self.mix(word, mults[0])) << 0x18) | \
((self.mix(word, mults[1])) << 0x10) | \
((self.mix(word, mults[2])) << 0x08) | \
((self.mix(word, mults[3])) << 0x00)
def mix(self, word, mix):
'''Mixes a word according to a given multiplier.'''
return (self.mult_table[mix[0]][((word >> 0x18) & 0xFF)]) ^ \
(self.mult_table[mix[1]][((word >> 0x10) & 0xFF)]) ^ \
(self.mult_table[mix[2]][((word >> 0x08) & 0xFF)]) ^ \
(self.mult_table[mix[3]][((word >> 0x00) & 0xFF)]) & 0xFF
def key_schedule_core(self, word, i, sbox=sbox_enc):
'''Performs core key scheduling operation.'''
return self.send_through_sbox(self.rotate_op(word), sbox) ^ (self.rcon_op(i) << 0x18)
def pad_block(self, block):
'''Pads a block using CMS padding.'''
assert(len(block) <= self.block_size)
num_pad = self.block_size - len(block)
return block + (chr(num_pad) * num_pad)
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