Add RS decoder

fastcrypto-tbls/benches/polynomial.rs

@@ -9,6 +9,37 @@ use std::num::NonZeroU16;
 
 mod polynomial_benches {
     use super::*;
+    use fastcrypto_tbls::threshold_schnorr::gao::RSDecoder;
+    use fastcrypto_tbls::threshold_schnorr::S;
+    use fastcrypto_tbls::types::ShareIndex;
+    use itertools::Itertools;
+
+    fn rs_decoder(c: &mut Criterion) {
+        const SIZES: [usize; 4] = [128, 256, 512, 1024];
+
+        for n in SIZES {
+            let k = n / 3;
+            let a = (1..=n)
+                .map(|i| ShareIndex::new(i as u16).unwrap())
+                .collect_vec();
+            let decoder = RSDecoder::new(a.clone(), k);
+
+            let message: Vec<S> = (0..k).map(|i| S::from((i * 10) as u128)).collect();
+            let code_word = decoder.encode(message.clone()).unwrap();
+
+            // Introduce errors
+            let mut received = code_word.clone();
+            received[4] = S::from(20u128); // Error at position 4
+            received[2] = S::from(200u128); // Error at position 2
+
+            let mut rs_decoder: BenchmarkGroup<_> = c.benchmark_group("RS Decoder");
+            rs_decoder.bench_function(format!("n={}, k={}", n, k).as_str(), |b| {
+                b.iter(|| {
+                    decoder.decode(&received).unwrap();
+                })
+            });
+        }
+    }
 
     fn polynomials(c: &mut Criterion) {
         const SIZES: [usize; 7] = [128, 256, 512, 1024, 2048, 4096, 8192];
@@ -77,7 +108,7 @@ mod polynomial_benches {
     criterion_group! {
         name = polynomial_benches;
         config = Criterion::default();
-        targets = polynomials,
+        targets = polynomials, rs_decoder,
     }
 }
 

fastcrypto-tbls/src/dkg_v1.rs

@@ -311,12 +311,12 @@ where
             return Err(FastCryptoError::InvalidMessage);
         };
 
-        if self.t as usize != msg.vss_pk.degree() + 1 {
+        if self.t as usize != msg.vss_pk.degree_bound() + 1 {
             warn!(
                 "DKG: Message sanity check failed for id {}, expected degree={}, got {}",
                 msg.sender,
                 self.t - 1,
-                msg.vss_pk.degree()
+                msg.vss_pk.degree_bound()
             );
             return Err(FastCryptoError::InvalidMessage);
         }

fastcrypto-tbls/src/dl_verification.rs

@@ -47,7 +47,7 @@ pub fn verify_poly_evals<G: GroupElement + MultiScalarMul, R: AllowedRng>(
     poly: &Poly<G>,
     rng: &mut R,
 ) -> FastCryptoResult<()> {
-    assert!(poly.degree() > 0);
+    assert!(poly.degree_bound() > 0);
     if evals.is_empty() {
         return Ok(());
     }
@@ -59,7 +59,7 @@ pub fn verify_poly_evals<G: GroupElement + MultiScalarMul, R: AllowedRng>(
         .iter()
         .map(|e| G::ScalarType::from(e.index.get().into()))
         .collect::<Vec<_>>();
-    let coeffs = batch_coefficients(&rs, &evals_as_scalars, poly.degree());
+    let coeffs = batch_coefficients(&rs, &evals_as_scalars, poly.degree_bound());
     let rhs = G::multi_scalar_mul(&coeffs, poly.as_vec()).expect("sizes match");
 
     if lhs != rhs {

fastcrypto-tbls/src/lib.rs

@@ -20,7 +20,6 @@ pub mod nodes;
 pub mod polynomial;
 pub mod random_oracle;
 pub mod tbls;
-#[cfg(any(test, feature = "experimental"))]
 pub mod threshold_schnorr;
 pub mod types;