diff options
Diffstat (limited to 'python/lilliput.py')
| -rw-r--r-- | python/lilliput.py | 55 |
1 files changed, 24 insertions, 31 deletions
diff --git a/python/lilliput.py b/python/lilliput.py index 79f14e5..3fe41bf 100644 --- a/python/lilliput.py +++ b/python/lilliput.py @@ -1,34 +1,23 @@ import lilliput_ae_1 import lilliput_ae_2 -import parameters_i_128 as i_128 -import parameters_i_192 as i_192 -import parameters_i_256 as i_256 -import parameters_ii_128 as ii_128 -import parameters_ii_192 as ii_192 -import parameters_ii_256 as ii_256 - BLOCK_BYTES = 16 N_BYTES = 15 -def GetParameters(mode = 1, length = 128) : - if(mode == 1 and length == 128) : - return (i_128.KEY_BITS, i_128.TWEAK_BITS, i_128.ROUNDS) - - if(mode == 1 and length == 192) : - return (i_192.KEY_BITS, i_192.TWEAK_BITS, i_192.ROUNDS) +def _getParameters(mode=1, key_length=128) : + rounds = { + 128: 32, + 192: 36, + 256: 42 + } - if(mode == 1 and length == 256) : - return (i_256.KEY_BITS, i_256.TWEAK_BITS, i_256.ROUNDS) + tweak_lengths = { + 1: 192, + 2: 128 + } - if(mode == 2 and length == 128) : - return (ii_128.KEY_BITS, ii_128.TWEAK_BITS, ii_128.ROUNDS) + return tweak_lengths[mode], rounds[key_length] - if(mode == 2 and length == 192) : - return (ii_192.KEY_BITS, ii_192.TWEAK_BITS, ii_192.ROUNDS) - - if(mode == 2 and length == 256) : - return (ii_256.KEY_BITS, ii_256.TWEAK_BITS, ii_256.ROUNDS) def ArrayToBlockbytesMatrix(array) : length = len(array) @@ -53,18 +42,21 @@ def BlockbytesMatrixToBytes(matrix): ############################################ -def _checkInputs(key, length, nonce): - if len(key) != length//8: - raise ValueError('invalid key size: {} != {}'.format(len(key), length//8)) +def _checkInputs(key, nonce): + valid_key_lengths = (128, 192, 256) + + if len(key)*8 not in valid_key_lengths: + raise ValueError('invalid key size: {} not in {}'.format(len(key)*8, valid_key_lengths)) if len(nonce) != N_BYTES: raise ValueError('nonce must be {}-byte long'.format(N_BYTES)) -def mainEnc(plaintext, adata, key, nonce, mode=1, length=128): - _checkInputs(key, length, nonce) +def mainEnc(plaintext, adata, key, nonce, mode): + _checkInputs(key, nonce) - (key_bits, tweak_bits, rounds) = GetParameters(mode, length) + key_bits = len(key)*8 + tweak_bits, rounds = _getParameters(mode, key_bits) A = adata M = plaintext @@ -84,10 +76,11 @@ def mainEnc(plaintext, adata, key, nonce, mode=1, length=128): return BlockbytesMatrixToBytes(C), bytes(tag) -def mainDec(ciphertext, tag, adata, key, nonce, mode=1, length=128): - _checkInputs(key, length, nonce) +def mainDec(ciphertext, tag, adata, key, nonce, mode): + _checkInputs(key, nonce) - (key_bits, tweak_bits, rounds) = GetParameters(mode, length) + key_bits = len(key)*8 + tweak_bits, rounds = _getParameters(mode, key_bits) A = adata C = ciphertext |