AESModeOfOperationCTR always uses 16 bytes counters?

[cristianocca]

aes = pyaes.AESModeOfOperationCTR(self.KEY, counter=pyaes.Counter(initial_value=iv))
print(len(aes._counter.value))

The counter value length seems to always be 16 regardless of if the key is 16 or 32 bytes. Is this the right behaviour? Or would this mean a security risk when using 32 bytes (256 bits) keys?

[cristianocca]

https://github.com/ricmoo/pyaes/blob/master/pyaes/aes.py#L281

The 128 should probably 256 when using 32 bytes keys.

Or not, the block size seems to always be 16 bytes regardless of the key size, so perhaps the function docs are wrong The counter must be the same size as the key size (ie. len(key)).