use curve25519_dalek::ristretto::CompressedRistretto;
use curve25519_dalek::scalar::Scalar;
use merlin::Transcript;
use crate::errors::ProofError;
pub trait TranscriptProtocol {
fn rangeproof_domain_sep(&mut self, n: u64, m: u64);
fn innerproduct_domain_sep(&mut self, n: u64);
fn r1cs_domain_sep(&mut self);
fn r1cs_1phase_domain_sep(&mut self);
fn r1cs_2phase_domain_sep(&mut self);
fn append_scalar(&mut self, label: &'static [u8], scalar: &Scalar);
fn append_point(&mut self, label: &'static [u8], point: &CompressedRistretto);
fn validate_and_append_point(
&mut self,
label: &'static [u8],
point: &CompressedRistretto,
) -> Result<(), ProofError>;
fn challenge_scalar(&mut self, label: &'static [u8]) -> Scalar;
}
impl TranscriptProtocol for Transcript {
fn rangeproof_domain_sep(&mut self, n: u64, m: u64) {
self.append_message(b"dom-sep", b"rangeproof v1");
self.append_u64(b"n", n);
self.append_u64(b"m", m);
}
fn innerproduct_domain_sep(&mut self, n: u64) {
self.append_message(b"dom-sep", b"ipp v1");
self.append_u64(b"n", n);
}
fn r1cs_domain_sep(&mut self) {
self.append_message(b"dom-sep", b"r1cs v1");
}
fn r1cs_1phase_domain_sep(&mut self) {
self.append_message(b"dom-sep", b"r1cs-1phase");
}
fn r1cs_2phase_domain_sep(&mut self) {
self.append_message(b"dom-sep", b"r1cs-2phase");
}
fn append_scalar(&mut self, label: &'static [u8], scalar: &Scalar) {
self.append_message(label, scalar.as_bytes());
}
fn append_point(&mut self, label: &'static [u8], point: &CompressedRistretto) {
self.append_message(label, point.as_bytes());
}
fn validate_and_append_point(
&mut self,
label: &'static [u8],
point: &CompressedRistretto,
) -> Result<(), ProofError> {
use curve25519_dalek::traits::IsIdentity;
if point.is_identity() {
Err(ProofError::VerificationError)
} else {
Ok(self.append_message(label, point.as_bytes()))
}
}
fn challenge_scalar(&mut self, label: &'static [u8]) -> Scalar {
let mut buf = [0u8; 64];
self.challenge_bytes(label, &mut buf);
Scalar::from_bytes_mod_order_wide(&buf)
}
}