pub fn hash_auth_message(message: &str) -> Result<[u8; 40], AuthTokenError>Expand description
Hash the auth-token ASCII message to its 40-byte Fp5 digest.
Splits the bytes into 8-byte little-endian Goldilocks limbs (zero-padding
the trailing chunk) and runs hash_to_quintic_extension over the limbs.
Returns the canonical 40-byte little-endian encoding the Schnorr binding
signs over.
ยงErrors
Returns an error if any 8-byte chunk decodes to a non-canonical Goldilocks element. The
auth-token format is ASCII ('0'..='9' and ':'), so every byte sits in 0..=0x3A and the
case is unreachable for tokens emitted by auth_token_message; the error path exists for
callers that pass arbitrary preimages.