def decrypt(encrypted_text, mode, key, iv):
encrypted_data = b64decode(encrypted_text.encode('utf-8'))
decrypted_data = None
if mode == 'ECB':
decrypted_data = GOST.remove_padding(
ecb_decrypt(key, encrypted_data))
elif mode == 'CBC':
decrypted_data = GOST.remove_padding(
cbc_decrypt(key, encrypted_data))
elif mode == 'CFB':
decrypted_data = GOST.remove_padding(
cfb_decrypt(key, encrypted_data, bytes.fromhex(iv)))
return decrypted_data.decode('utf-8')
def unwrap_gost(kek, data, sbox=DEFAULT_SBOX):
"""28147-89 key unwrapping
:param kek: key encryption key
:type kek: bytes, 32 bytes
:param data: wrapped key
:type data: bytes, 44 bytes
:returns: unwrapped CEK
:rtype: 32 bytes
"""
if len(data) != 44:
raise ValueError("Invalid data length")
ukm, cek_enc, cek_mac = data[:8], data[8:8 + 32], data[-4:]
cek = ecb_decrypt(kek, cek_enc, sbox=sbox)
if MAC(kek, data=cek, iv=ukm, sbox=sbox).digest()[:4] != cek_mac:
raise ValueError("Invalid MAC")
return cek
def unwrap_gost(kek, data):
"""28147-89 key unwrapping
:param kek: key encryption key
:type kek: bytes, 32 bytes
:param data: wrapped key
:type data: bytes, 44 bytes
:return: unwrapped CEK
:rtype: 32 bytes
"""
if len(data) != 44:
raise ValueError("Invalid data length")
ukm, cek_enc, cek_mac = data[:8], data[8:8 + 32], data[-4:]
cek = ecb_decrypt(kek, cek_enc)
if MAC(kek, iv=ukm)(cek)[:4] != cek_mac:
raise ValueError("Invalid MAC")
return cek
def test_gcl(self):
""" Test vectors from libgcl3
"""
sbox = "id-Gost28147-89-TestParamSet"
key = hexdec(b"0475f6e05038fbfad2c7c390edb3ca3d1547124291ae1e8a2f79cd9ed2bcefbd")
plaintext = bytes(bytearray((
0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01, 0x00,
0x0f, 0x0e, 0x0d, 0x0c, 0x0b, 0x0a, 0x09, 0x08,
0x17, 0x16, 0x15, 0x14, 0x13, 0x12, 0x11, 0x10,
0x1f, 0x1e, 0x1d, 0x1c, 0x1b, 0x1a, 0x19, 0x18,
0x27, 0x26, 0x25, 0x24, 0x23, 0x22, 0x21, 0x20,
0x2f, 0x2e, 0x2d, 0x2c, 0x2b, 0x2a, 0x29, 0x28,
0x37, 0x36, 0x35, 0x34, 0x33, 0x32, 0x31, 0x30,
0x3f, 0x3e, 0x3d, 0x3c, 0x3b, 0x3a, 0x39, 0x38,
0x47, 0x46, 0x45, 0x44, 0x43, 0x42, 0x41, 0x40,
0x4f, 0x4e, 0x4d, 0x4c, 0x4b, 0x4a, 0x49, 0x48,
0x57, 0x56, 0x55, 0x54, 0x53, 0x52, 0x51, 0x50,
0x5f, 0x5e, 0x5d, 0x5c, 0x5b, 0x5a, 0x59, 0x58,
0x67, 0x66, 0x65, 0x64, 0x63, 0x62, 0x61, 0x60,
0x6f, 0x6e, 0x6d, 0x6c, 0x6b, 0x6a, 0x69, 0x68,
0x77, 0x76, 0x75, 0x74, 0x73, 0x72, 0x71, 0x70,
0x7f, 0x7e, 0x7d, 0x7c, 0x7b, 0x7a, 0x79, 0x78,
0x87, 0x86, 0x85, 0x84, 0x83, 0x82, 0x81, 0x80,
0x8f, 0x8e, 0x8d, 0x8c, 0x8b, 0x8a, 0x89, 0x88,
0x97, 0x96, 0x95, 0x94, 0x93, 0x92, 0x91, 0x90,
0x9f, 0x9e, 0x9d, 0x9c, 0x9b, 0x9a, 0x99, 0x98,
0xa7, 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1, 0xa0,
0xaf, 0xae, 0xad, 0xac, 0xab, 0xaa, 0xa9, 0xa8,
0xb7, 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1, 0xb0,
0xbf, 0xbe, 0xbd, 0xbc, 0xbb, 0xba, 0xb9, 0xb8,
0xc7, 0xc6, 0xc5, 0xc4, 0xc3, 0xc2, 0xc1, 0xc0,
0xcf, 0xce, 0xcd, 0xcc, 0xcb, 0xca, 0xc9, 0xc8,
0xd7, 0xd6, 0xd5, 0xd4, 0xd3, 0xd2, 0xd1, 0xd0,
0xdf, 0xde, 0xdd, 0xdc, 0xdb, 0xda, 0xd9, 0xd8,
0xe7, 0xe6, 0xe5, 0xe4, 0xe3, 0xe2, 0xe1, 0xe0,
0xef, 0xee, 0xed, 0xec, 0xeb, 0xea, 0xe9, 0xe8,
0xf7, 0xf6, 0xf5, 0xf4, 0xf3, 0xf2, 0xf1, 0xf0,
0xff, 0xfe, 0xfd, 0xfc, 0xfb, 0xfa, 0xf9, 0xf8,
)))
ciphertext = bytes(bytearray((
0x4b, 0x8c, 0x4c, 0x98, 0x15, 0xf2, 0x4a, 0xea,
0x1e, 0xc3, 0x57, 0x09, 0xb3, 0xbc, 0x2e, 0xd1,
0xe0, 0xd1, 0xf2, 0x22, 0x65, 0x2d, 0x59, 0x18,
0xf7, 0xdf, 0xfc, 0x80, 0x4b, 0xde, 0x5c, 0x68,
0x46, 0x53, 0x75, 0x53, 0xa7, 0x46, 0x0d, 0xec,
0x05, 0x1f, 0x1b, 0xd3, 0x0a, 0x63, 0x1a, 0xb7,
0x78, 0xc4, 0x43, 0xe0, 0x5d, 0x3e, 0xa4, 0x0e,
0x2d, 0x7e, 0x23, 0xa9, 0x1b, 0xc9, 0x02, 0xbc,
0x21, 0x0c, 0x84, 0xcb, 0x0d, 0x0a, 0x07, 0xc8,
0x7b, 0xd0, 0xfb, 0xb5, 0x1a, 0x14, 0x04, 0x5c,
0xa2, 0x53, 0x97, 0x71, 0x2e, 0x5c, 0xc2, 0x8f,
0x39, 0x3f, 0x6f, 0x52, 0xf2, 0x30, 0x26, 0x4e,
0x8c, 0xe0, 0xd1, 0x01, 0x75, 0x6d, 0xdc, 0xd3,
0x03, 0x79, 0x1e, 0xca, 0xd5, 0xc1, 0x0e, 0x12,
0x53, 0x0a, 0x78, 0xe2, 0x0a, 0xb1, 0x1c, 0xea,
0x3a, 0xf8, 0x55, 0xb9, 0x7c, 0xe1, 0x0b, 0xba,
0xa0, 0xc8, 0x96, 0xeb, 0x50, 0x5a, 0xd3, 0x60,
0x43, 0xa3, 0x0f, 0x98, 0xdb, 0xd9, 0x50, 0x6d,
0x63, 0x91, 0xaf, 0x01, 0x40, 0xe9, 0x75, 0x5a,
0x46, 0x5c, 0x1f, 0x19, 0x4a, 0x0b, 0x89, 0x9b,
0xc4, 0xf6, 0xf8, 0xf5, 0x2f, 0x87, 0x3f, 0xfa,
0x26, 0xd4, 0xf8, 0x25, 0xba, 0x1f, 0x98, 0x82,
0xfc, 0x26, 0xaf, 0x2d, 0xc0, 0xf9, 0xc4, 0x58,
0x49, 0xfa, 0x09, 0x80, 0x02, 0x62, 0xa4, 0x34,
0x2d, 0xcb, 0x5a, 0x6b, 0xab, 0x61, 0x5d, 0x08,
0xd4, 0x26, 0xe0, 0x08, 0x13, 0xd6, 0x2e, 0x02,
0x2a, 0x37, 0xe8, 0xd0, 0xcf, 0x36, 0xf1, 0xc7,
0xc0, 0x3f, 0x9b, 0x21, 0x60, 0xbd, 0x29, 0x2d,
0x2e, 0x01, 0x48, 0x4e, 0xf8, 0x8f, 0x20, 0x16,
0x8a, 0xbf, 0x82, 0xdc, 0x32, 0x7a, 0xa3, 0x18,
0x69, 0xd1, 0x50, 0x59, 0x31, 0x91, 0xf2, 0x6c,
0x5a, 0x5f, 0xca, 0x58, 0x9a, 0xb2, 0x2d, 0xb2,
)))
encrypted = ecb_encrypt(key, plaintext, sbox=sbox)
self.assertSequenceEqual(encrypted, ciphertext)
decrypted = ecb_decrypt(key, encrypted, sbox=sbox)
self.assertSequenceEqual(decrypted, plaintext)