diff options
Diffstat (limited to 'lib/Crypto/Cipher/blockalgo.py')
| -rw-r--r-- | lib/Crypto/Cipher/blockalgo.py | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/lib/Crypto/Cipher/blockalgo.py b/lib/Crypto/Cipher/blockalgo.py index 9ac8710..0d21f44 100644 --- a/lib/Crypto/Cipher/blockalgo.py +++ b/lib/Crypto/Cipher/blockalgo.py @@ -329,14 +329,17 @@ class _GHASH(_SmoothMAC): (x^128 + x^7 + x^2 + x + 1). """ - def __init__(self, hash_subkey, block_size): + def __init__(self, hash_subkey, block_size, table_size='64K'): _SmoothMAC.__init__(self, block_size, None, 0) - self._hash_subkey = galois._ghash_expand(hash_subkey) + if table_size == '64K': + self._hash_subkey = galois._ghash_expand(hash_subkey) + else: + self._hash_subkey = hash_subkey self._last_y = bchr(0) * 16 self._mac = galois._ghash def copy(self): - clone = _GHASH(self._hash_subkey, self._bs) + clone = _GHASH(self._hash_subkey, self._bs, table_size='0K') _SmoothMAC._deep_copy(self, clone) clone._last_y = self._last_y return clone @@ -433,7 +436,7 @@ class BlockAlgo: bchr(0) * fill + long_to_bytes(8 * len(self.nonce), 8)) - mac = _GHASH(hash_subkey, factory.block_size) + mac = _GHASH(hash_subkey, factory.block_size, '0K') mac.update(ghash_in) self._j0 = bytes_to_long(mac.digest()) @@ -443,7 +446,7 @@ class BlockAlgo: self._cipher = self._factory.new(key, MODE_CTR, counter=ctr) # Step 5 - Bootstrat GHASH - self._cipherMAC = _GHASH(hash_subkey, factory.block_size) + self._cipherMAC = _GHASH(hash_subkey, factory.block_size, '64K') # Step 6 - Prepare GCTR cipher for GMAC ctr = Counter.new(128, initial_value=self._j0, allow_wraparound=True) |