pub fn encrypt_data_segment<C: BlockCipher16>(
plaintext: &str,
cipher: &C,
) -> Result<EncryptedDataSegment, Hj212Error>Expand description
Encrypt a data-segment string using 16-byte blocks and leaving the trailing remainder as plaintext.
Note: The standard says “16 characters”; HJ212 payloads are typically ASCII. This implementation requires ASCII to avoid splitting inside UTF-8 codepoints.