pub fn encode_challenge_response(
response: &ChallengeResponse,
buf: &mut [u8],
) -> Result<usize, ProtocolError>Expand description
Encode a client’s auth challenge-response into buf, as the frame
payload without the 4-byte length prefix:
[tag:u8][signature:64][pubkey:32].
The inverse of decode_challenge_response, kept beside it so the
layout has one home. Returns Err(Truncated) if buf is shorter
than CHALLENGE_RESPONSE_LEN.