- Created a NISigmaProtocol from a GroupMorphismPreimage (see the non_interactive_protocol.rs test)

- Fixed the group_morphism file name
- Rest: Fixed the SigmaProtocol implementation for SchnorrProof

Author: nougzarm

src/toolbox/sigma/group_mophism.rs renamed to src/toolbox/sigma/group_morphism.rs

@@ -1,12 +1,12 @@
 pub mod r#trait;
 pub mod proof_composition;
 pub mod fiat_shamir;
-pub mod group_mophism;
+pub mod group_morphism;
 pub mod schnorr_proof;
 pub mod transcript;
 
 pub use r#trait::SigmaProtocol;
 pub use proof_composition::{AndProtocol, OrProtocol};
 pub use fiat_shamir::NISigmaProtocol;
 pub use schnorr_proof::SchnorrProof;
-pub use group_mophism::GroupMorphismPreimage;
+pub use group_morphism::GroupMorphismPreimage;

src/toolbox/sigma/mod.rs

@@ -32,7 +32,7 @@ where
     ) -> (Self::Commitment, Self::ProverState) {
         let mut nonces: Vec<G::Scalar> = Vec::new();
         for _i in 0..self.morphismp.morphism.num_scalars {
-            nonces.push(<G as Group>::Scalar::random(rng));
+            nonces.push(<G as Group>::Scalar::random(&mut *rng));
         }
         let prover_state = (nonces.clone(), witness.clone());
         let commitment = self.morphismp.morphism.evaluate(&nonces);
@@ -103,7 +103,7 @@ where
         for i in 0..scalar_nb {
             let start = i * point_size;
             let end = start + point_size;
-            let mut buf = [0u8; point_size];
+            let mut buf = vec![0u8; point_size];
             buf.copy_from_slice(&data[start..end]);
             let elem_ct = G::from_bytes(&buf);
             if !bool::from(elem_ct.is_some()) {           

src/toolbox/sigma/schnorr_proof.rs

@@ -1,7 +1,9 @@
+use group::Group;
 use rand::rngs::OsRng;
 use curve25519_dalek::ristretto::RistrettoPoint;
 use curve25519_dalek::scalar::Scalar;
 
+use lox_zkp::toolbox::sigma::group_mophism::GroupMorphismPreimage;
 use lox_zkp::toolbox::sigma::schnorr_proof::SchnorrProof;
 use lox_zkp::toolbox::sigma::transcript::transcriptcodec::KeccakTranscript;
 use lox_zkp::toolbox::sigma::fiat_shamir::NISigmaProtocol;
@@ -20,7 +22,18 @@ fn fiat_shamir_schnorr_proof_ristretto() {
     let w = Scalar::random(&mut rng);
     let H = G * w;
 
-    let protocol = SchnorrProof { generator: G, target: H };
+    let morphismp: GroupMorphismPreimage<RistrettoPoint> = GroupMorphismPreimage::new();
+
+    // Scalars and Points bases settings
+    morphismp.allocate_scalars(1);
+    morphismp.allocate_elements(1);
+    morphismp.set_elements(&[(0, G)]);
+
+    // The H = z * G equeation where z is the unique scalar variable
+    morphismp.append_equation(H, &[(0, 0)]);
+
+    // The SigmaProtocol induced by morphismp
+    let protocol = SchnorrProof { morphismp };
 
     // Fiat-Shamir wrapper
     let mut nizk = NISigmaProtocol::<_, KeccakTranscript<G>, G>::new(domain_sep, protocol);