Hash fixed_commitments and permutations into transcript

src/plonk.rs

@@ -9,7 +9,7 @@ use crate::arithmetic::CurveAffine;
 use crate::poly::{
     commitment::Params, Coeff, EvaluationDomain, ExtendedLagrangeCoeff, LagrangeCoeff, Polynomial,
 };
-use crate::transcript::ChallengeScalar;
+use crate::transcript::{ChallengeScalar, Transcript};
 
 mod circuit;
 mod keygen;
@@ -74,6 +74,18 @@ impl<C: CurveAffine> VerifyingKey<C> {
             cs,
         })
     }
+
+    /// Hashes a verification key into a transcript.
+    pub fn hash<T: Transcript<C>>(&self, transcript: &mut T) -> io::Result<()> {
+        for commitment in &self.fixed_commitments {
+            transcript.common_point(*commitment)?;
+        }
+        for permutation in &self.permutations {
+            permutation.hash(transcript)?;
+        }
+
+        Ok(())
+    }
 }
 
 /// This is a proving key which allows for the creation of proofs for a

src/plonk/permutation.rs

@@ -4,6 +4,7 @@ use super::circuit::{Any, Column};
 use crate::{
     arithmetic::CurveAffine,
     poly::{Coeff, ExtendedLagrangeCoeff, LagrangeCoeff, Polynomial},
+    transcript::Transcript,
 };
 
 pub(crate) mod keygen;
@@ -66,6 +67,14 @@ impl<C: CurveAffine> VerifyingKey<C> {
             .collect::<Result<Vec<_>, _>>()?;
         Ok(VerifyingKey { commitments })
     }
+
+    pub(crate) fn hash<T: Transcript<C>>(&self, transcript: &mut T) -> io::Result<()> {
+        for commitment in &self.commitments {
+            transcript.common_point(*commitment)?;
+        }
+
+        Ok(())
+    }
 }
 
 /// The proving key for a single permutation argument.

src/plonk/prover.rs

@@ -30,6 +30,9 @@ pub fn create_proof<C: CurveAffine, T: TranscriptWrite<C>, ConcreteCircuit: Circ
         }
     }
 
+    // Hash verification key into transcript
+    pk.vk.hash(transcript).map_err(|_| Error::TranscriptError)?;
+
     let domain = &pk.vk.domain;
     let mut meta = ConstraintSystem::default();
     let config = ConcreteCircuit::configure(&mut meta);

src/plonk/verifier.rs

@@ -29,6 +29,9 @@ pub fn verify_proof<'a, C: CurveAffine, T: TranscriptRead<C>>(
 
     let num_proofs = instance_commitments.len();
 
+    // Hash verification key into transcript
+    vk.hash(transcript).map_err(|_| Error::TranscriptError)?;
+
     for instance_commitments in instance_commitments.iter() {
         // Hash the instance (external) commitments into the transcript
         for commitment in *instance_commitments {