(PHP 4 >= 4.0.2)

mcrypt_enc_get_supported_key_sizes -- Returns an array with the supported keysizes of the opened algorithm


array mcrypt_enc_get_supported_key_sizes (resource td)

Returns an array with the key sizes supported by the algorithm specified by the encryption descriptor. If it returns an empty array then all key sizes between 1 and mcrypt_enc_get_key_size() are supported by the algorithm.