implement alternative transcript with poseidon backend

Cargo.toml

@@ -33,6 +33,11 @@ ark-std = { version = "^0.3.0"}
 ark-bls12-377 = { version = "^0.3.0", features = ["r1cs","curve"] }
 ark-serialize = { version = "^0.3.0", features = ["derive"] }
 ark-sponge = { version = "^0.3.0" , features = ["r1cs"] }
+ark-crypto-primitives = { version = "^0.3.0", default-features = true }
+ark-r1cs-std = { version = "^0.3.0", default-features = false }
+ark-nonnative-field = { version = "0.3.0", default-features = false }
+ark-relations = { version = "^0.3.0", default-features = false }
+ark-snark = { version = "^0.3.0", default-features = false }
 
 lazy_static = "1.4.0"
 rand = { version = "0.8", features = [ "std", "std_rng" ] }
@@ -64,4 +69,7 @@ harness = false
 [features]
 default = ["curve25519-dalek/simd_backend"]
 multicore = ["rayon"]
-profile = []
+profile = []
+
+[patch.crates-io]
+ark-r1cs-std = { git = "https://github.com/arkworks-rs/r1cs-std/", rev = "a2a5ac491ae005ba2afd03fd21b7d3160d794a83"}

README.md

@@ -43,7 +43,8 @@ Some of our public APIs' style is inspired by the underlying crates we use.
 # extern crate libspartan;
 # extern crate merlin;
 # use libspartan::{Instance, SNARKGens, SNARK};
-# use merlin::Transcript;
+# use libspartan::poseidon_transcript::PoseidonTranscript;
+# use libspartan::parameters::poseidon_params;
 # fn main() {
     // specify the size of an R1CS instance
     let num_vars = 1024;
@@ -60,12 +61,14 @@ Some of our public APIs' style is inspired by the underlying crates we use.
     // create a commitment to the R1CS instance
     let (comm, decomm) = SNARK::encode(&inst, &gens);
 
+     let params = poseidon_params();
+
     // produce a proof of satisfiability
-    let mut prover_transcript = Transcript::new(b"snark_example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let proof = SNARK::prove(&inst, &comm, &decomm, vars, &inputs, &gens, &mut prover_transcript);
 
     // verify the proof of satisfiability
-    let mut verifier_transcript = Transcript::new(b"snark_example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&comm, &inputs, &mut verifier_transcript, &gens)
       .is_ok());
@@ -79,7 +82,8 @@ Here is another example to use the NIZK variant of the Spartan proof system:
 # extern crate libspartan;
 # extern crate merlin;
 # use libspartan::{Instance, NIZKGens, NIZK};
-# use merlin::Transcript;
+# use libspartan::poseidon_transcript::PoseidonTranscript;
+# use libspartan::parameters::poseidon_params;
 # fn main() {
     // specify the size of an R1CS instance
     let num_vars = 1024;
@@ -92,12 +96,14 @@ Here is another example to use the NIZK variant of the Spartan proof system:
     // ask the library to produce a synthentic R1CS instance
     let (inst, vars, inputs) = Instance::produce_synthetic_r1cs(num_cons, num_vars, num_inputs);
 
+     let params = poseidon_params();
+
     // produce a proof of satisfiability
-    let mut prover_transcript = Transcript::new(b"nizk_example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let proof = NIZK::prove(&inst, vars, &inputs, &gens, &mut prover_transcript);
 
     // verify the proof of satisfiability
-    let mut verifier_transcript = Transcript::new(b"nizk_example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&inst, &inputs, &mut verifier_transcript, &gens)
       .is_ok());
@@ -114,8 +120,10 @@ Finally, we provide an example that specifies a custom R1CS instance instead of
 # extern crate merlin;
 # mod scalar;
 # use scalar::Scalar;
+# use libspartan::parameters::poseidon_params;
 # use libspartan::{InputsAssignment, Instance, SNARKGens, VarsAssignment, SNARK};
-# use merlin::Transcript;
+# use libspartan::poseidon_transcript::{AppendToPoseidon, PoseidonTranscript};
+#
 # use ark_ff::{PrimeField, Field, BigInteger};
 # use ark_std::{One, Zero, UniformRand};
 # fn main() {
@@ -135,9 +143,10 @@ Finally, we provide an example that specifies a custom R1CS instance instead of
 
   // create a commitment to the R1CS instance
   let (comm, decomm) = SNARK::encode(&inst, &gens);
+   let params = poseidon_params();
 
   // produce a proof of satisfiability
-  let mut prover_transcript = Transcript::new(b"snark_example");
+  let mut prover_transcript = PoseidonTranscript::new(&params);
   let proof = SNARK::prove(
     &inst,
     &comm,
@@ -149,7 +158,7 @@ Finally, we provide an example that specifies a custom R1CS instance instead of
   );
 
   // verify the proof of satisfiability
-  let mut verifier_transcript = Transcript::new(b"snark_example");
+  let mut verifier_transcript = PoseidonTranscript::new(&params);
   assert!(proof
     .verify(&comm, &assignment_inputs, &mut verifier_transcript, &gens)
     .is_ok());

benches/nizk.rs

@@ -7,7 +7,9 @@ extern crate libspartan;
 extern crate merlin;
 extern crate sha3;
 
-use libspartan::{Instance, NIZKGens, NIZK};
+use libspartan::{
+  parameters::poseidon_params, poseidon_transcript::PoseidonTranscript, Instance, NIZKGens, NIZK,
+};
 use merlin::Transcript;
 
 use criterion::*;
@@ -22,6 +24,8 @@ fn nizk_prove_benchmark(c: &mut Criterion) {
     let num_cons = num_vars;
     let num_inputs = 10;
 
+    let params = poseidon_params();
+
     let (inst, vars, inputs) = Instance::produce_synthetic_r1cs(num_cons, num_vars, num_inputs);
 
     let gens = NIZKGens::new(num_cons, num_vars, num_inputs);
@@ -29,7 +33,7 @@ fn nizk_prove_benchmark(c: &mut Criterion) {
     let name = format!("NIZK_prove_{}", num_vars);
     group.bench_function(&name, move |b| {
       b.iter(|| {
-        let mut prover_transcript = Transcript::new(b"example");
+        let mut prover_transcript = PoseidonTranscript::new(&params);
         NIZK::prove(
           black_box(&inst),
           black_box(vars.clone()),
@@ -55,15 +59,15 @@ fn nizk_verify_benchmark(c: &mut Criterion) {
     let (inst, vars, inputs) = Instance::produce_synthetic_r1cs(num_cons, num_vars, num_inputs);
 
     let gens = NIZKGens::new(num_cons, num_vars, num_inputs);
-
+    let params = poseidon_params();
     // produce a proof of satisfiability
-    let mut prover_transcript = Transcript::new(b"example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let proof = NIZK::prove(&inst, vars, &inputs, &gens, &mut prover_transcript);
 
     let name = format!("NIZK_verify_{}", num_cons);
     group.bench_function(&name, move |b| {
       b.iter(|| {
-        let mut verifier_transcript = Transcript::new(b"example");
+        let mut verifier_transcript = PoseidonTranscript::new(&params);
         assert!(proof
           .verify(
             black_box(&inst),

benches/snark.rs

@@ -2,7 +2,11 @@
 extern crate libspartan;
 extern crate merlin;
 
-use libspartan::{Instance, SNARKGens, SNARK};
+use libspartan::{
+  parameters::poseidon_params,
+  poseidon_transcript::{self, PoseidonTranscript},
+  Instance, SNARKGens, SNARK,
+};
 use merlin::Transcript;
 
 use criterion::*;
@@ -42,6 +46,8 @@ fn snark_prove_benchmark(c: &mut Criterion) {
     let num_cons = num_vars;
     let num_inputs = 10;
 
+    let params = poseidon_params();
+
     let (inst, vars, inputs) = Instance::produce_synthetic_r1cs(num_cons, num_vars, num_inputs);
 
     // produce public parameters
@@ -54,7 +60,7 @@ fn snark_prove_benchmark(c: &mut Criterion) {
     let name = format!("SNARK_prove_{}", num_cons);
     group.bench_function(&name, move |b| {
       b.iter(|| {
-        let mut prover_transcript = Transcript::new(b"example");
+        let mut prover_transcript = PoseidonTranscript::new(&params);
         SNARK::prove(
           black_box(&inst),
           black_box(&comm),
@@ -76,6 +82,8 @@ fn snark_verify_benchmark(c: &mut Criterion) {
     let mut group = c.benchmark_group("SNARK_verify_benchmark");
     group.plot_config(plot_config);
 
+    let params = poseidon_params();
+
     let num_vars = (2_usize).pow(s as u32);
     let num_cons = num_vars;
     let num_inputs = 10;
@@ -88,7 +96,7 @@ fn snark_verify_benchmark(c: &mut Criterion) {
     let (comm, decomm) = SNARK::encode(&inst, &gens);
 
     // produce a proof of satisfiability
-    let mut prover_transcript = Transcript::new(b"example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let proof = SNARK::prove(
       &inst,
       &comm,
@@ -103,7 +111,7 @@ fn snark_verify_benchmark(c: &mut Criterion) {
     let name = format!("SNARK_verify_{}", num_cons);
     group.bench_function(&name, move |b| {
       b.iter(|| {
-        let mut verifier_transcript = Transcript::new(b"example");
+        let mut verifier_transcript = PoseidonTranscript::new(&params);
         assert!(proof
           .verify(
             black_box(&comm),

examples/cubic.rs

@@ -11,7 +11,15 @@
 use ark_bls12_377::Fr as Scalar;
 use ark_ff::{BigInteger, PrimeField};
 use ark_std::{One, UniformRand, Zero};
+<<<<<<< HEAD
 use libspartan::{InputsAssignment, Instance, SNARKGens, VarsAssignment, SNARK};
+=======
+use libspartan::{
+  parameters::poseidon_params,
+  poseidon_transcript::{self, PoseidonTranscript},
+  InputsAssignment, Instance, SNARKGens, VarsAssignment, SNARK,
+};
+>>>>>>> implement alternative transcript with poseidon backend
 use merlin::Transcript;
 
 #[allow(non_snake_case)]
@@ -119,6 +127,8 @@ fn main() {
     assignment_inputs,
   ) = produce_r1cs();
 
+  let params = poseidon_params();
+
   // produce public parameters
   let gens = SNARKGens::new(num_cons, num_vars, num_inputs, num_non_zero_entries);
 
@@ -126,7 +136,7 @@ fn main() {
   let (comm, decomm) = SNARK::encode(&inst, &gens);
 
   // produce a proof of satisfiability
-  let mut prover_transcript = Transcript::new(b"snark_example");
+  let mut prover_transcript = PoseidonTranscript::new(&params);
   let proof = SNARK::prove(
     &inst,
     &comm,
@@ -138,7 +148,7 @@ fn main() {
   );
 
   // verify the proof of satisfiability
-  let mut verifier_transcript = Transcript::new(b"snark_example");
+  let mut verifier_transcript = PoseidonTranscript::new(&params);
   assert!(proof
     .verify(&comm, &assignment_inputs, &mut verifier_transcript, &gens)
     .is_ok());

profiler/nizk.rs

@@ -6,9 +6,11 @@ extern crate libspartan;
 extern crate merlin;
 extern crate rand;
 
+use ark_serialize::*;
+use libspartan::parameters::poseidon_params;
+use libspartan::poseidon_transcript::PoseidonTranscript;
 use libspartan::{Instance, NIZKGens, NIZK};
 use merlin::Transcript;
-use ark_serialize::*;
 
 fn print(msg: &str) {
   let star = "* ";
@@ -31,8 +33,9 @@ pub fn main() {
     // produce public generators
     let gens = NIZKGens::new(num_cons, num_vars, num_inputs);
 
+    let params = poseidon_params();
     // produce a proof of satisfiability
-    let mut prover_transcript = Transcript::new(b"nizk_example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let proof = NIZK::prove(&inst, vars, &inputs, &gens, &mut prover_transcript);
 
     let mut proof_encoded = Vec::new();
@@ -41,7 +44,7 @@ pub fn main() {
     print(&msg_proof_len);
 
     // verify the proof of satisfiability
-    let mut verifier_transcript = Transcript::new(b"nizk_example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&inst, &inputs, &mut verifier_transcript, &gens)
       .is_ok());

profiler/snark.rs

@@ -5,9 +5,10 @@ extern crate flate2;
 extern crate libspartan;
 extern crate merlin;
 
-use libspartan::{Instance, SNARKGens, SNARK};
-use merlin::Transcript;
 use ark_serialize::*;
+use libspartan::parameters::poseidon_params;
+use libspartan::poseidon_transcript::PoseidonTranscript;
+use libspartan::{Instance, SNARKGens, SNARK};
 
 fn print(msg: &str) {
   let star = "* ";
@@ -33,8 +34,10 @@ pub fn main() {
     // create a commitment to R1CSInstance
     let (comm, decomm) = SNARK::encode(&inst, &gens);
 
+    let params = poseidon_params();
+
     // produce a proof of satisfiability
-    let mut prover_transcript = Transcript::new(b"snark_example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let proof = SNARK::prove(
       &inst,
       &comm,
@@ -51,7 +54,7 @@ pub fn main() {
     print(&msg_proof_len);
 
     // verify the proof of satisfiability
-    let mut verifier_transcript = Transcript::new(b"snark_example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&comm, &inputs, &mut verifier_transcript, &gens)
       .is_ok());

src/commitments.rs

@@ -1,17 +1,16 @@
+use super::group::{Fq, GroupElement, GroupElementAffine, VartimeMultiscalarMul, GROUP_BASEPOINT};
+use super::scalar::Scalar;
 use crate::group::{CompressGroupElement, DecompressGroupElement};
 use crate::parameters::*;
-use super::group::{GroupElement, VartimeMultiscalarMul, GROUP_BASEPOINT, GroupElementAffine, CurveField};
-use super::scalar::Scalar;
-use ark_bls12_377::Fq;
+use ark_ec::{AffineCurve, ProjectiveCurve};
 use ark_ff::PrimeField;
+use ark_serialize::{CanonicalDeserialize, CanonicalSerialize};
+use ark_sponge::poseidon::{PoseidonParameters, PoseidonSponge};
 use ark_sponge::CryptographicSponge;
 use digest::{ExtendableOutput, Input};
 use sha3::Shake256;
 use std::io::Read;
 use std::str::FromStr;
-use ark_serialize::{CanonicalDeserialize, CanonicalSerialize};
-use ark_ec::{ProjectiveCurve, AffineCurve};
-use ark_sponge::poseidon::{PoseidonParameters, PoseidonSponge};
 
 #[derive(Debug)]
 pub struct MultiCommitGens {
@@ -21,47 +20,22 @@ pub struct MultiCommitGens {
 }
 
 impl MultiCommitGens {
-  pub fn poseidon_params() -> PoseidonParameters<CurveField> {
-    let arks = P1["ark"]
-        .members()
-        .map(|ark| {
-            ark.members()
-                .map(|v| Fq::from_str(v.as_str().unwrap()).unwrap())
-                .collect::<Vec<_>>()
-        })
-        .collect::<Vec<_>>();
-    let mds = P1["mds"]
-        .members()
-        .map(|m| {
-            m.members()
-                .map(|v| Fq::from_str(v.as_str().unwrap()).unwrap())
-                .collect::<Vec<_>>()
-        })
-        .collect::<Vec<_>>();
-    PoseidonParameters::new(
-        P1["full_rounds"].as_u32().unwrap(),
-        P1["partial_rounds"].as_u32().unwrap(),
-        P1["alpha"].as_u64().unwrap(),
-        mds,
-        arks,
-    )
-  }
-   pub fn new(n: usize, label: &[u8]) -> Self {
-    let params = MultiCommitGens::poseidon_params();
+  pub fn new(n: usize, label: &[u8]) -> Self {
+    let params = poseidon_params();
     let mut sponge = PoseidonSponge::new(&params);
     sponge.absorb(&label);
     sponge.absorb(&GROUP_BASEPOINT.into_affine());
-    
+
     let mut gens: Vec<GroupElement> = Vec::new();
     for _ in 0..n + 1 {
       let mut el_aff: Option<GroupElementAffine> = None;
       while el_aff.is_some() != true {
         let uniform_bytes = sponge.squeeze_bytes(64);
-      el_aff = GroupElementAffine::from_random_bytes(&uniform_bytes);
+        el_aff = GroupElementAffine::from_random_bytes(&uniform_bytes);
+      }
+      let el = el_aff.unwrap().mul_by_cofactor_to_projective();
+      gens.push(el);
     }
-    let el = el_aff.unwrap().mul_by_cofactor_to_projective();
-    gens.push(el);
-  }
 
     MultiCommitGens {
       n,
@@ -111,7 +85,6 @@ impl Commitments for Vec {
   fn commit(&self, blind: &Scalar, gens_n: &MultiCommitGens) -> GroupElement {
     assert_eq!(gens_n.n, self.len());
     GroupElement::vartime_multiscalar_mul(self, &gens_n.G) + gens_n.h.mul(blind.into_repr())
-  
   }
 }
 
@@ -119,6 +92,5 @@ impl Commitments for [Scalar] {
   fn commit(&self, blind: &Scalar, gens_n: &MultiCommitGens) -> GroupElement {
     assert_eq!(gens_n.n, self.len());
     GroupElement::vartime_multiscalar_mul(self, &gens_n.G) + gens_n.h.mul(blind.into_repr())
-    
   }
 }

src/dense_mlpoly.rs

@@ -1,18 +1,21 @@
 #![allow(clippy::too_many_arguments)]
+use crate::poseidon_transcript::{AppendToPoseidon, PoseidonTranscript};
+
 use super::commitments::{Commitments, MultiCommitGens};
 use super::errors::ProofVerifyError;
-use super::group::{GroupElement, CompressedGroup, VartimeMultiscalarMul, CompressGroupElement, DecompressGroupElement};
+use super::group::{
+  CompressGroupElement, CompressedGroup, DecompressGroupElement, GroupElement,
+  VartimeMultiscalarMul,
+};
 use super::math::Math;
 use super::nizk::{DotProductProofGens, DotProductProofLog};
 use super::random::RandomTape;
 use super::scalar::Scalar;
 use super::transcript::{AppendToTranscript, ProofTranscript};
+use ark_ff::{One, Zero};
+use ark_serialize::*;
 use core::ops::Index;
 use merlin::Transcript;
-use ark_serialize::*;
-use ark_ff::{One,Zero};
-
-
 
 #[cfg(feature = "multicore")]
 use rayon::prelude::*;
@@ -299,6 +302,14 @@ impl AppendToTranscript for PolyCommitment {
   }
 }
 
+impl AppendToPoseidon for PolyCommitment {
+  fn append_to_poseidon(&self, transcript: &mut PoseidonTranscript) {
+    for i in 0..self.C.len() {
+      transcript.append_point(&self.C[i]);
+    }
+  }
+}
+
 #[derive(Debug, CanonicalSerialize, CanonicalDeserialize)]
 pub struct PolyEvalProof {
   proof: DotProductProofLog,
@@ -316,10 +327,10 @@ impl PolyEvalProof {
     Zr: &Scalar,                   // evaluation of \widetilde{Z}(r)
     blind_Zr_opt: Option<&Scalar>, // specifies a blind for Zr
     gens: &PolyCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
   ) -> (PolyEvalProof, CompressedGroup) {
-    transcript.append_protocol_name(PolyEvalProof::protocol_name());
+    // transcript.append_protocol_name(PolyEvalProof::protocol_name());
 
     // assert vectors are of the right size
     assert_eq!(poly.get_num_vars(), r.len());
@@ -367,19 +378,23 @@ impl PolyEvalProof {
   pub fn verify(
     &self,
     gens: &PolyCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     r: &[Scalar],           // point at which the polynomial is evaluated
     C_Zr: &CompressedGroup, // commitment to \widetilde{Z}(r)
     comm: &PolyCommitment,
   ) -> Result<(), ProofVerifyError> {
-    transcript.append_protocol_name(PolyEvalProof::protocol_name());
+    // transcript.append_protocol_name(PolyEvalProof::protocol_name());
 
     // compute L and R
     let eq = EqPolynomial::new(r.to_vec());
     let (L, R) = eq.compute_factored_evals();
 
     // compute a weighted sum of commitments and L
-    let C_decompressed = comm.C.iter().map(|pt| GroupElement::decompress(pt).unwrap()).collect::<Vec<GroupElement>>();
+    let C_decompressed = comm
+      .C
+      .iter()
+      .map(|pt| GroupElement::decompress(pt).unwrap())
+      .collect::<Vec<GroupElement>>();
 
     let C_LZ = GroupElement::vartime_multiscalar_mul(&L, C_decompressed.as_slice()).compress();
 
@@ -391,7 +406,7 @@ impl PolyEvalProof {
   pub fn verify_plain(
     &self,
     gens: &PolyCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     r: &[Scalar], // point at which the polynomial is evaluated
     Zr: &Scalar,  // evaluation \widetilde{Z}(r)
     comm: &PolyCommitment,
@@ -405,8 +420,10 @@ impl PolyEvalProof {
 
 #[cfg(test)]
 mod tests {
+  use crate::parameters::poseidon_params;
+
   use super::*;
-  use ark_std::{UniformRand};
+  use ark_std::UniformRand;
 
   fn evaluate_with_LR(Z: &[Scalar], r: &[Scalar]) -> Scalar {
     let eq = EqPolynomial::new(r.to_vec());
@@ -436,7 +453,7 @@ mod tests {
       Scalar::one(),
       Scalar::from(2),
       Scalar::from(1),
-      Scalar::from(4)
+      Scalar::from(4),
     ];
 
     // r = [4,3]
@@ -569,7 +586,7 @@ mod tests {
       Scalar::from(1),
       Scalar::from(2),
       Scalar::from(1),
-      Scalar::from(4)
+      Scalar::from(4),
     ];
     let poly = DensePolynomial::new(Z);
 
@@ -582,7 +599,8 @@ mod tests {
     let (poly_commitment, blinds) = poly.commit(&gens, None);
 
     let mut random_tape = RandomTape::new(b"proof");
-    let mut prover_transcript = Transcript::new(b"example");
+    let params = poseidon_params();
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let (proof, C_Zr) = PolyEvalProof::prove(
       &poly,
       Some(&blinds),
@@ -594,7 +612,7 @@ mod tests {
       &mut random_tape,
     );
 
-    let mut verifier_transcript = Transcript::new(b"example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&gens, &mut verifier_transcript, &r, &C_Zr, &poly_commitment)
       .is_ok());

src/group.rs

@@ -1,24 +1,20 @@
 use crate::errors::ProofVerifyError;
 use ark_ec::msm::VariableBaseMSM;
 use ark_ff::PrimeField;
-use digest::DynDigest;
-use lazy_static::lazy_static;
-use num_bigint::BigInt;
+
 
 use lazy_static::lazy_static;
 use num_bigint::BigInt;
 
 use super::scalar::Scalar;
 use ark_ec::{AffineCurve, ProjectiveCurve};
-use ark_ec::{AffineCurve, ProjectiveCurve};
-use ark_serialize::*;
 use ark_serialize::*;
 use core::borrow::Borrow;
-use core::ops::{Mul, MulAssign};
 
 pub type GroupElement = ark_bls12_377::G1Projective;
 pub type GroupElementAffine = ark_bls12_377::G1Affine;
-pub type CurveField = ark_bls12_377::Fq;
+pub type Fq = ark_bls12_377::Fq;
+pub type Fr = ark_bls12_377::Fr;
 
 #[derive(Clone, Eq, PartialEq, Hash, Debug, CanonicalSerialize, CanonicalDeserialize)]
 pub struct CompressedGroup(pub Vec<u8>);

src/lib.rs

@@ -26,7 +26,6 @@ mod errors;
 mod group;
 mod math;
 mod nizk;
-mod parameters;
 mod product_tree;
 mod r1csinstance;
 mod r1csproof;
@@ -38,12 +37,18 @@ mod timer;
 mod transcript;
 mod unipoly;
 
+/// TODO
+pub mod parameters;
+/// TODO
+pub mod poseidon_transcript;
+
 use ark_ff::{BigInteger, Field, PrimeField};
 use ark_serialize::*;
 use ark_std::{One, UniformRand, Zero};
 use core::cmp::max;
 use errors::{ProofVerifyError, R1CSError};
 use merlin::Transcript;
+use poseidon_transcript::{AppendToPoseidon, PoseidonTranscript};
 use r1csinstance::{
   R1CSCommitment, R1CSCommitmentGens, R1CSDecommitment, R1CSEvalProof, R1CSInstance,
 };
@@ -354,7 +359,7 @@ impl SNARK {
     vars: VarsAssignment,
     inputs: &InputsAssignment,
     gens: &SNARKGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> Self {
     let timer_prove = Timer::new("SNARK::prove");
 
@@ -362,8 +367,8 @@ impl SNARK {
     // to aid the prover produce its randomness
     let mut random_tape = RandomTape::new(b"proof");
 
-    transcript.append_protocol_name(SNARK::protocol_name());
-    comm.comm.append_to_transcript(b"comm", transcript);
+    // transcript.append_protocol_name(SNARK::protocol_name());
+    comm.comm.append_to_poseidon(transcript);
 
     let (r1cs_sat_proof, rx, ry) = {
       let (proof, rx, ry) = {
@@ -400,9 +405,9 @@ impl SNARK {
     let timer_eval = Timer::new("eval_sparse_polys");
     let inst_evals = {
       let (Ar, Br, Cr) = inst.inst.evaluate(&rx, &ry);
-      Ar.append_to_transcript(b"Ar_claim", transcript);
-      Br.append_to_transcript(b"Br_claim", transcript);
-      Cr.append_to_transcript(b"Cr_claim", transcript);
+      transcript.append_scalar(&Ar);
+      transcript.append_scalar(&Br);
+      transcript.append_scalar(&Cr);
       (Ar, Br, Cr)
     };
     timer_eval.stop();
@@ -437,14 +442,14 @@ impl SNARK {
     &self,
     comm: &ComputationCommitment,
     input: &InputsAssignment,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     gens: &SNARKGens,
   ) -> Result<(), ProofVerifyError> {
     let timer_verify = Timer::new("SNARK::verify");
-    transcript.append_protocol_name(SNARK::protocol_name());
+    // transcript.append_protocol_name(SNARK::protocol_name());
 
     // append a commitment to the computation to the transcript
-    comm.comm.append_to_transcript(b"comm", transcript);
+    comm.comm.append_to_poseidon(transcript);
 
     let timer_sat_proof = Timer::new("verify_sat_proof");
     assert_eq!(input.assignment.len(), comm.comm.get_num_inputs());
@@ -460,9 +465,12 @@ impl SNARK {
 
     let timer_eval_proof = Timer::new("verify_eval_proof");
     let (Ar, Br, Cr) = &self.inst_evals;
-    Ar.append_to_transcript(b"Ar_claim", transcript);
-    Br.append_to_transcript(b"Br_claim", transcript);
-    Cr.append_to_transcript(b"Cr_claim", transcript);
+    // Ar.append_to_transcript(b"Ar_claim", transcript);
+    // Br.append_to_transcript(b"Br_claim", transcript);
+    // Cr.append_to_transcript(b"Cr_claim", transcript);
+    transcript.append_scalar(&Ar);
+    transcript.append_scalar(&Br);
+    transcript.append_scalar(&Cr);
     self.r1cs_eval_proof.verify(
       &comm.comm,
       &rx,
@@ -516,15 +524,20 @@ impl NIZK {
     vars: VarsAssignment,
     input: &InputsAssignment,
     gens: &NIZKGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> Self {
     let timer_prove = Timer::new("NIZK::prove");
     // we create a Transcript object seeded with a random Scalar
     // to aid the prover produce its randomness
     let mut random_tape = RandomTape::new(b"proof");
 
+<<<<<<< HEAD
     transcript.append_protocol_name(NIZK::protocol_name());
     transcript.append_message(b"R1CSInstanceDigest", &inst.digest);
+=======
+    // transcript.append_protocol_name(NIZK::protocol_name());
+    inst.inst.append_to_poseidon(transcript);
+>>>>>>> simplify transcript and change merlin backend to poseidon
 
     let (r1cs_sat_proof, rx, ry) = {
       // we might need to pad variables
@@ -564,13 +577,18 @@ impl NIZK {
     &self,
     inst: &Instance,
     input: &InputsAssignment,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     gens: &NIZKGens,
   ) -> Result<(), ProofVerifyError> {
     let timer_verify = Timer::new("NIZK::verify");
 
+<<<<<<< HEAD
     transcript.append_protocol_name(NIZK::protocol_name());
     transcript.append_message(b"R1CSInstanceDigest", &inst.digest);
+=======
+    // transcript.append_protocol_name(NIZK::protocol_name());
+    inst.inst.append_to_poseidon(transcript);
+>>>>>>> simplify transcript and change merlin backend to poseidon
 
     // We send evaluations of A, B, C at r = (rx, ry) as claims
     // to enable the verifier complete the first sum-check
@@ -602,6 +620,8 @@ impl NIZK {
 
 #[cfg(test)]
 mod tests {
+  use crate::parameters::poseidon_params;
+
   use super::*;
   use ark_ff::PrimeField;
 
@@ -620,8 +640,10 @@ mod tests {
     // create a commitment to R1CSInstance
     let (comm, decomm) = SNARK::encode(&inst, &gens);
 
+    let params = poseidon_params();
+
     // produce a proof
-    let mut prover_transcript = Transcript::new(b"example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let proof = SNARK::prove(
       &inst,
       &comm,
@@ -633,7 +655,7 @@ mod tests {
     );
 
     // verify the proof
-    let mut verifier_transcript = Transcript::new(b"example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&comm, &inputs, &mut verifier_transcript, &gens)
       .is_ok());
@@ -732,8 +754,10 @@ mod tests {
     // create a commitment to the R1CS instance
     let (comm, decomm) = SNARK::encode(&inst, &gens);
 
+    let params = poseidon_params();
+
     // produce a SNARK
-    let mut prover_transcript = Transcript::new(b"snark_example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let proof = SNARK::prove(
       &inst,
       &comm,
@@ -745,7 +769,7 @@ mod tests {
     );
 
     // verify the SNARK
-    let mut verifier_transcript = Transcript::new(b"snark_example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&comm, &assignment_inputs, &mut verifier_transcript, &gens)
       .is_ok());
@@ -753,8 +777,10 @@ mod tests {
     // NIZK public params
     let gens = NIZKGens::new(num_cons, num_vars, num_inputs);
 
+    let params = poseidon_params();
+
     // produce a NIZK
-    let mut prover_transcript = Transcript::new(b"nizk_example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let proof = NIZK::prove(
       &inst,
       assignment_vars,
@@ -764,7 +790,7 @@ mod tests {
     );
 
     // verify the NIZK
-    let mut verifier_transcript = Transcript::new(b"nizk_example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&inst, &assignment_inputs, &mut verifier_transcript, &gens)
       .is_ok());

src/nizk/bullet.rs

@@ -4,6 +4,7 @@
 #![allow(clippy::type_complexity)]
 #![allow(clippy::too_many_arguments)]
 use crate::math::Math;
+use crate::poseidon_transcript::PoseidonTranscript;
 
 use super::super::errors::ProofVerifyError;
 use super::super::group::{
@@ -38,7 +39,7 @@ impl BulletReductionProof {
   /// The lengths of the vectors must all be the same, and must all be
   /// either 0 or a power of 2.
   pub fn prove(
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     Q: &GroupElement,
     G_vec: &[GroupElement],
     H: &GroupElement,
@@ -122,10 +123,10 @@ impl BulletReductionProof {
           .as_slice(),
       );
 
-      transcript.append_point(b"L", &L.compress());
-      transcript.append_point(b"R", &R.compress());
+      transcript.append_point(&L.compress());
+      transcript.append_point(&R.compress());
 
-      let u = transcript.challenge_scalar(b"u");
+      let u = transcript.challenge_scalar();
       let u_inv = u.inverse().unwrap();
 
       for i in 0..n {
@@ -163,7 +164,7 @@ impl BulletReductionProof {
   fn verification_scalars(
     &self,
     n: usize,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> Result<(Vec<Scalar>, Vec<Scalar>, Vec<Scalar>), ProofVerifyError> {
     let lg_n = self.L_vec.len();
     if lg_n >= 32 {
@@ -178,9 +179,9 @@ impl BulletReductionProof {
     // 1. Recompute x_k,...,x_1 based on the proof transcript
     let mut challenges = Vec::with_capacity(lg_n);
     for (L, R) in self.L_vec.iter().zip(self.R_vec.iter()) {
-      transcript.append_point(b"L", L);
-      transcript.append_point(b"R", R);
-      challenges.push(transcript.challenge_scalar(b"u"));
+      transcript.append_point(L);
+      transcript.append_point(R);
+      challenges.push(transcript.challenge_scalar());
     }
 
     // 2. Compute 1/(u_k...u_1) and 1/u_k, ..., 1/u_1
@@ -224,7 +225,7 @@ impl BulletReductionProof {
     &self,
     n: usize,
     a: &[Scalar],
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     Gamma: &GroupElement,
     G: &[GroupElement],
   ) -> Result<(GroupElement, GroupElement, Scalar), ProofVerifyError> {

src/nizk/mod.rs

@@ -1,5 +1,6 @@
 #![allow(clippy::too_many_arguments)]
 use crate::math::Math;
+use crate::poseidon_transcript::{AppendToPoseidon, PoseidonTranscript};
 
 use super::commitments::{Commitments, MultiCommitGens};
 use super::errors::ProofVerifyError;
@@ -34,24 +35,24 @@ impl KnowledgeProof {
 
   pub fn prove(
     gens_n: &MultiCommitGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
     x: &Scalar,
     r: &Scalar,
   ) -> (KnowledgeProof, CompressedGroup) {
-    transcript.append_protocol_name(KnowledgeProof::protocol_name());
+    // transcript.append_protocol_name(KnowledgeProof::protocol_name());
 
     // produce two random Scalars
     let t1 = random_tape.random_scalar(b"t1");
     let t2 = random_tape.random_scalar(b"t2");
 
     let C = x.commit(r, gens_n).compress();
-    C.append_to_transcript(b"C", transcript);
+    C.append_to_poseidon(transcript);
 
     let alpha = t1.commit(&t2, gens_n).compress();
-    alpha.append_to_transcript(b"alpha", transcript);
+    alpha.append_to_poseidon(transcript);
 
-    let c = transcript.challenge_scalar(b"c");
+    let c = transcript.challenge_scalar();
 
     let z1 = c * x + t1;
     let z2 = c * r + t2;
@@ -62,14 +63,14 @@ impl KnowledgeProof {
   pub fn verify(
     &self,
     gens_n: &MultiCommitGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     C: &CompressedGroup,
   ) -> Result<(), ProofVerifyError> {
-    transcript.append_protocol_name(KnowledgeProof::protocol_name());
-    C.append_to_transcript(b"C", transcript);
-    self.alpha.append_to_transcript(b"alpha", transcript);
+    // transcript.append_protocol_name(KnowledgeProof::protocol_name());
+    C.append_to_poseidon(transcript);
+    self.alpha.append_to_poseidon(transcript);
 
-    let c = transcript.challenge_scalar(b"c");
+    let c = transcript.challenge_scalar();
 
     let lhs = self.z1.commit(&self.z2, gens_n).compress();
     let rhs = (C.unpack()?.mul(c.into_repr()) + self.alpha.unpack()?).compress();
@@ -95,28 +96,28 @@ impl EqualityProof {
 
   pub fn prove(
     gens_n: &MultiCommitGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
     v1: &Scalar,
     s1: &Scalar,
     v2: &Scalar,
     s2: &Scalar,
   ) -> (EqualityProof, CompressedGroup, CompressedGroup) {
-    transcript.append_protocol_name(EqualityProof::protocol_name());
+    // transcript.append_protocol_name(EqualityProof::protocol_name());
 
     // produce a random Scalar
     let r = random_tape.random_scalar(b"r");
 
     let C1 = v1.commit(s1, gens_n).compress();
-    C1.append_to_transcript(b"C1", transcript);
+    transcript.append_point(&C1);
 
     let C2 = v2.commit(s2, gens_n).compress();
-    C2.append_to_transcript(b"C2", transcript);
+    transcript.append_point(&C2);
 
     let alpha = gens_n.h.mul(r.into_repr()).compress();
-    alpha.append_to_transcript(b"alpha", transcript);
+    transcript.append_point(&alpha);
 
-    let c = transcript.challenge_scalar(b"c");
+    let c = transcript.challenge_scalar();
 
     let z = c * ((*s1) - s2) + r;
 
@@ -126,16 +127,17 @@ impl EqualityProof {
   pub fn verify(
     &self,
     gens_n: &MultiCommitGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     C1: &CompressedGroup,
     C2: &CompressedGroup,
   ) -> Result<(), ProofVerifyError> {
-    transcript.append_protocol_name(EqualityProof::protocol_name());
-    C1.append_to_transcript(b"C1", transcript);
-    C2.append_to_transcript(b"C2", transcript);
-    self.alpha.append_to_transcript(b"alpha", transcript);
+    // transcript.append_protocol_name(EqualityProof::protocol_name());
 
-    let c = transcript.challenge_scalar(b"c");
+    transcript.append_point(&C1);
+    transcript.append_point(&C2);
+    transcript.append_point(&self.alpha);
+
+    let c = transcript.challenge_scalar();
     let rhs = {
       let C = C1.unpack()? - C2.unpack()?;
       (C.mul(c.into_repr()) + self.alpha.unpack()?).compress()
@@ -167,7 +169,7 @@ impl ProductProof {
 
   pub fn prove(
     gens_n: &MultiCommitGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
     x: &Scalar,
     rX: &Scalar,
@@ -181,7 +183,7 @@ impl ProductProof {
     CompressedGroup,
     CompressedGroup,
   ) {
-    transcript.append_protocol_name(ProductProof::protocol_name());
+    // transcript.append_protocol_name(ProductProof::protocol_name());
 
     // produce five random Scalar
     let b1 = random_tape.random_scalar(b"b1");
@@ -193,23 +195,22 @@ impl ProductProof {
     let X_unc = x.commit(rX, gens_n);
 
     let X = X_unc.compress();
-    X.append_to_transcript(b"X", transcript);
-
+    transcript.append_point(&X);
     let X_new = GroupElement::decompress(&X);
 
     assert_eq!(X_unc, X_new.unwrap());
 
     let Y = y.commit(rY, gens_n).compress();
-    Y.append_to_transcript(b"Y", transcript);
+    transcript.append_point(&Y);
 
     let Z = z.commit(rZ, gens_n).compress();
-    Z.append_to_transcript(b"Z", transcript);
+    transcript.append_point(&Z);
 
     let alpha = b1.commit(&b2, gens_n).compress();
-    alpha.append_to_transcript(b"alpha", transcript);
+    transcript.append_point(&alpha);
 
     let beta = b3.commit(&b4, gens_n).compress();
-    beta.append_to_transcript(b"beta", transcript);
+    transcript.append_point(&beta);
 
     let delta = {
       let gens_X = &MultiCommitGens {
@@ -219,9 +220,9 @@ impl ProductProof {
       };
       b3.commit(&b5, gens_X).compress()
     };
-    delta.append_to_transcript(b"delta", transcript);
+    transcript.append_point(&delta);
 
-    let c = transcript.challenge_scalar(b"c");
+    let c = transcript.challenge_scalar();
 
     let z1 = b1 + c * x;
     let z2 = b2 + c * rX;
@@ -263,19 +264,19 @@ impl ProductProof {
   pub fn verify(
     &self,
     gens_n: &MultiCommitGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     X: &CompressedGroup,
     Y: &CompressedGroup,
     Z: &CompressedGroup,
   ) -> Result<(), ProofVerifyError> {
-    transcript.append_protocol_name(ProductProof::protocol_name());
+    // transcript.append_protocol_name(ProductProof::protocol_name());
 
-    X.append_to_transcript(b"X", transcript);
-    Y.append_to_transcript(b"Y", transcript);
-    Z.append_to_transcript(b"Z", transcript);
-    self.alpha.append_to_transcript(b"alpha", transcript);
-    self.beta.append_to_transcript(b"beta", transcript);
-    self.delta.append_to_transcript(b"delta", transcript);
+    X.append_to_poseidon(transcript);
+    Y.append_to_poseidon(transcript);
+    Z.append_to_poseidon(transcript);
+    self.alpha.append_to_poseidon(transcript);
+    self.beta.append_to_poseidon(transcript);
+    self.delta.append_to_poseidon(transcript);
 
     let z1 = self.z[0];
     let z2 = self.z[1];
@@ -283,7 +284,7 @@ impl ProductProof {
     let z4 = self.z[3];
     let z5 = self.z[4];
 
-    let c = transcript.challenge_scalar(b"c");
+    let c = transcript.challenge_scalar();
 
     if ProductProof::check_equality(&self.alpha, X, &c, gens_n, &z1, &z2)
       && ProductProof::check_equality(&self.beta, Y, &c, gens_n, &z3, &z4)
@@ -329,7 +330,7 @@ impl DotProductProof {
   pub fn prove(
     gens_1: &MultiCommitGens,
     gens_n: &MultiCommitGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
     x_vec: &[Scalar],
     blind_x: &Scalar,
@@ -337,7 +338,7 @@ impl DotProductProof {
     y: &Scalar,
     blind_y: &Scalar,
   ) -> (DotProductProof, CompressedGroup, CompressedGroup) {
-    transcript.append_protocol_name(DotProductProof::protocol_name());
+    // transcript.append_protocol_name(DotProductProof::protocol_name());
 
     let n = x_vec.len();
     assert_eq!(x_vec.len(), a_vec.len());
@@ -350,22 +351,22 @@ impl DotProductProof {
     let r_beta = random_tape.random_scalar(b"r_beta");
 
     let Cx = x_vec.commit(blind_x, gens_n).compress();
-    Cx.append_to_transcript(b"Cx", transcript);
+    Cx.append_to_poseidon(transcript);
 
     let Cy = y.commit(blind_y, gens_1).compress();
-    Cy.append_to_transcript(b"Cy", transcript);
+    Cy.append_to_poseidon(transcript);
 
-    a_vec.append_to_transcript(b"a", transcript);
+    transcript.append_scalar_vector(&a_vec.to_vec());
 
     let delta = d_vec.commit(&r_delta, gens_n).compress();
-    delta.append_to_transcript(b"delta", transcript);
+    delta.append_to_poseidon(transcript);
 
     let dotproduct_a_d = DotProductProof::compute_dotproduct(a_vec, &d_vec);
 
     let beta = dotproduct_a_d.commit(&r_beta, gens_1).compress();
-    beta.append_to_transcript(b"beta", transcript);
+    beta.append_to_poseidon(transcript);
 
-    let c = transcript.challenge_scalar(b"c");
+    let c = transcript.challenge_scalar();
 
     let z = (0..d_vec.len())
       .map(|i| c * x_vec[i] + d_vec[i])
@@ -391,7 +392,7 @@ impl DotProductProof {
     &self,
     gens_1: &MultiCommitGens,
     gens_n: &MultiCommitGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     a: &[Scalar],
     Cx: &CompressedGroup,
     Cy: &CompressedGroup,
@@ -399,14 +400,14 @@ impl DotProductProof {
     assert_eq!(gens_n.n, a.len());
     assert_eq!(gens_1.n, 1);
 
-    transcript.append_protocol_name(DotProductProof::protocol_name());
-    Cx.append_to_transcript(b"Cx", transcript);
-    Cy.append_to_transcript(b"Cy", transcript);
-    a.append_to_transcript(b"a", transcript);
-    self.delta.append_to_transcript(b"delta", transcript);
-    self.beta.append_to_transcript(b"beta", transcript);
+    // transcript.append_protocol_name(DotProductProof::protocol_name());
+    Cx.append_to_poseidon(transcript);
+    Cy.append_to_poseidon(transcript);
+    transcript.append_scalar_vector(&a.to_vec());
+    self.delta.append_to_poseidon(transcript);
+    self.beta.append_to_poseidon(transcript);
 
-    let c = transcript.challenge_scalar(b"c");
+    let c = transcript.challenge_scalar();
 
     let mut result = Cx.unpack()?.mul(c.into_repr()) + self.delta.unpack()?
       == self.z.commit(&self.z_delta, gens_n);
@@ -456,7 +457,7 @@ impl DotProductProofLog {
 
   pub fn prove(
     gens: &DotProductProofGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
     x_vec: &[Scalar],
     blind_x: &Scalar,
@@ -464,7 +465,7 @@ impl DotProductProofLog {
     y: &Scalar,
     blind_y: &Scalar,
   ) -> (DotProductProofLog, CompressedGroup, CompressedGroup) {
-    transcript.append_protocol_name(DotProductProofLog::protocol_name());
+    // transcript.append_protocol_name(DotProductProofLog::protocol_name());
 
     let n = x_vec.len();
     assert_eq!(x_vec.len(), a_vec.len());
@@ -483,12 +484,11 @@ impl DotProductProofLog {
     };
 
     let Cx = x_vec.commit(blind_x, &gens.gens_n).compress();
-    Cx.append_to_transcript(b"Cx", transcript);
+    transcript.append_point(&Cx);
 
     let Cy = y.commit(blind_y, &gens.gens_1).compress();
-    Cy.append_to_transcript(b"Cy", transcript);
-
-    a_vec.append_to_transcript(b"a", transcript);
+    transcript.append_point(&Cy);
+    transcript.append_scalar_vector(&a_vec.to_vec());
 
     let blind_Gamma = (*blind_x) + blind_y;
     let (bullet_reduction_proof, _Gamma_hat, x_hat, a_hat, g_hat, rhat_Gamma) =
@@ -512,12 +512,12 @@ impl DotProductProofLog {
       };
       d.commit(&r_delta, &gens_hat).compress()
     };
-    delta.append_to_transcript(b"delta", transcript);
+    transcript.append_point(&delta);
 
     let beta = d.commit(&r_beta, &gens.gens_1).compress();
-    beta.append_to_transcript(b"beta", transcript);
+    transcript.append_point(&beta);
 
-    let c = transcript.challenge_scalar(b"c");
+    let c = transcript.challenge_scalar();
 
     let z1 = d + c * y_hat;
     let z2 = a_hat * (c * rhat_Gamma + r_beta) + r_delta;
@@ -539,7 +539,7 @@ impl DotProductProofLog {
     &self,
     n: usize,
     gens: &DotProductProofGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     a: &[Scalar],
     Cx: &CompressedGroup,
     Cy: &CompressedGroup,
@@ -547,10 +547,14 @@ impl DotProductProofLog {
     assert_eq!(gens.n, n);
     assert_eq!(a.len(), n);
 
-    transcript.append_protocol_name(DotProductProofLog::protocol_name());
-    Cx.append_to_transcript(b"Cx", transcript);
-    Cy.append_to_transcript(b"Cy", transcript);
-    a.append_to_transcript(b"a", transcript);
+    // transcript.append_protocol_name(DotProductProofLog::protocol_name());
+    // Cx.append_to_poseidon( transcript);
+    // Cy.append_to_poseidon( transcript);
+    // a.append_to_poseidon( transcript);
+
+    transcript.append_point(&Cx);
+    transcript.append_point(&Cy);
+    transcript.append_scalar_vector(&a.to_vec());
 
     let Gamma = Cx.unpack()? + Cy.unpack()?;
 
@@ -558,10 +562,13 @@ impl DotProductProofLog {
       self
         .bullet_reduction_proof
         .verify(n, a, transcript, &Gamma, &gens.gens_n.G)?;
-    self.delta.append_to_transcript(b"delta", transcript);
-    self.beta.append_to_transcript(b"beta", transcript);
+    // self.delta.append_to_poseidon( transcript);
+    // self.beta.append_to_poseidon( transcript);
+
+    transcript.append_point(&self.delta);
+    transcript.append_point(&self.beta);
 
-    let c = transcript.challenge_scalar(b"c");
+    let c = transcript.challenge_scalar();
 
     let c_s = &c;
     let beta_s = self.beta.unpack()?;
@@ -590,7 +597,7 @@ impl DotProductProofLog {
 mod tests {
   use std::marker::PhantomData;
 
-  use crate::group::VartimeMultiscalarMul;
+  use crate::{group::VartimeMultiscalarMul, parameters::poseidon_params};
 
   use super::*;
   use ark_bls12_377::{Fq, FqParameters, G1Affine};
@@ -605,12 +612,14 @@ mod tests {
     let x = Scalar::rand(&mut rng);
     let r = Scalar::rand(&mut rng);
 
+    let params = poseidon_params();
+
     let mut random_tape = RandomTape::new(b"proof");
-    let mut prover_transcript = Transcript::new(b"example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let (proof, committed_value) =
       KnowledgeProof::prove(&gens_1, &mut prover_transcript, &mut random_tape, &x, &r);
 
-    let mut verifier_transcript = Transcript::new(b"example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&gens_1, &mut verifier_transcript, &committed_value)
       .is_ok());
@@ -619,6 +628,7 @@ mod tests {
   #[test]
   fn check_equalityproof() {
     let mut rng = ark_std::rand::thread_rng();
+    let params = poseidon_params();
 
     let gens_1 = MultiCommitGens::new(1, b"test-equalityproof");
     let v1 = Scalar::rand(&mut rng);
@@ -627,7 +637,7 @@ mod tests {
     let s2 = Scalar::rand(&mut rng);
 
     let mut random_tape = RandomTape::new(b"proof");
-    let mut prover_transcript = Transcript::new(b"example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let (proof, C1, C2) = EqualityProof::prove(
       &gens_1,
       &mut prover_transcript,
@@ -638,7 +648,7 @@ mod tests {
       &s2,
     );
 
-    let mut verifier_transcript = Transcript::new(b"example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&gens_1, &mut verifier_transcript, &C1, &C2)
       .is_ok());
@@ -651,6 +661,7 @@ mod tests {
     let pt_c = pt.compress();
     let pt2 = GroupElement::decompress(&pt_c).unwrap();
     assert_eq!(pt, pt2);
+    let params = poseidon_params();
 
     let gens_1 = MultiCommitGens::new(1, b"test-productproof");
     let x = Scalar::rand(&mut rng);
@@ -661,7 +672,7 @@ mod tests {
     let rZ = Scalar::rand(&mut rng);
 
     let mut random_tape = RandomTape::new(b"proof");
-    let mut prover_transcript = Transcript::new(b"example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let (proof, X, Y, Z) = ProductProof::prove(
       &gens_1,
       &mut prover_transcript,
@@ -674,7 +685,7 @@ mod tests {
       &rZ,
     );
 
-    let mut verifier_transcript = Transcript::new(b"example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&gens_1, &mut verifier_transcript, &X, &Y, &Z)
       .is_ok());
@@ -688,6 +699,7 @@ mod tests {
 
     let gens_1 = MultiCommitGens::new(1, b"test-two");
     let gens_1024 = MultiCommitGens::new(n, b"test-1024");
+    let params = poseidon_params();
 
     let mut x: Vec<Scalar> = Vec::new();
     let mut a: Vec<Scalar> = Vec::new();
@@ -700,7 +712,7 @@ mod tests {
     let r_y = Scalar::rand(&mut rng);
 
     let mut random_tape = RandomTape::new(b"proof");
-    let mut prover_transcript = Transcript::new(b"example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let (proof, Cx, Cy) = DotProductProof::prove(
       &gens_1,
       &gens_1024,
@@ -713,7 +725,7 @@ mod tests {
       &r_y,
     );
 
-    let mut verifier_transcript = Transcript::new(b"example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(&gens_1, &gens_1024, &mut verifier_transcript, &a, &Cx, &Cy)
       .is_ok());
@@ -734,8 +746,9 @@ mod tests {
     let r_x = Scalar::rand(&mut rng);
     let r_y = Scalar::rand(&mut rng);
 
+    let params = poseidon_params();
     let mut random_tape = RandomTape::new(b"proof");
-    let mut prover_transcript = Transcript::new(b"example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let (proof, Cx, Cy) = DotProductProofLog::prove(
       &gens,
       &mut prover_transcript,
@@ -747,7 +760,7 @@ mod tests {
       &r_y,
     );
 
-    let mut verifier_transcript = Transcript::new(b"example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(n, &gens, &mut verifier_transcript, &a, &Cx, &Cy)
       .is_ok());

src/parameters.rs

@@ -1,10 +1,14 @@
+use std::str::FromStr;
+
+use ark_sponge::poseidon::PoseidonParameters;
 // Copyright: https://github.com/nikkolasg/ark-dkg/blob/main/src/parameters.rs
 use json::JsonValue;
 use lazy_static::lazy_static;
 
+use crate::group::Fq;
 
 lazy_static! {
-    // bls12377_rate2_constraints:
+    /// bls12377_rate2_constraints:
     pub static ref P1: JsonValue = object! {
         "ark" => array![
             array![
@@ -226,3 +230,31 @@ lazy_static! {
         "partial_rounds" => 31
     };
 }
+
+/// TODO
+pub fn poseidon_params() -> PoseidonParameters<Fq> {
+  let arks = P1["ark"]
+    .members()
+    .map(|ark| {
+      ark
+        .members()
+        .map(|v| Fq::from_str(v.as_str().unwrap()).unwrap())
+        .collect::<Vec<_>>()
+    })
+    .collect::<Vec<_>>();
+  let mds = P1["mds"]
+    .members()
+    .map(|m| {
+      m.members()
+        .map(|v| Fq::from_str(v.as_str().unwrap()).unwrap())
+        .collect::<Vec<_>>()
+    })
+    .collect::<Vec<_>>();
+  PoseidonParameters::new(
+    P1["full_rounds"].as_u32().unwrap(),
+    P1["partial_rounds"].as_u32().unwrap(),
+    P1["alpha"].as_u64().unwrap(),
+    mds,
+    arks,
+  )
+}

src/product_tree.rs

@@ -1,13 +1,15 @@
 #![allow(dead_code)]
+use crate::poseidon_transcript::PoseidonTranscript;
+
 use super::dense_mlpoly::DensePolynomial;
 use super::dense_mlpoly::EqPolynomial;
 use super::math::Math;
 use super::scalar::Scalar;
 use super::sumcheck::SumcheckInstanceProof;
 use super::transcript::ProofTranscript;
-use merlin::Transcript;
 use ark_serialize::*;
-use ark_std::{One};
+use ark_std::One;
+use merlin::Transcript;
 
 #[derive(Debug)]
 pub struct ProductCircuit {
@@ -122,7 +124,7 @@ impl LayerProof {
     claim: Scalar,
     num_rounds: usize,
     degree_bound: usize,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> (Scalar, Vec<Scalar>) {
     self
       .proof
@@ -146,7 +148,7 @@ impl LayerProofBatched {
     claim: Scalar,
     num_rounds: usize,
     degree_bound: usize,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> (Scalar, Vec<Scalar>) {
     self
       .proof
@@ -170,7 +172,7 @@ impl ProductCircuitEvalProof {
   #![allow(dead_code)]
   pub fn prove(
     circuit: &mut ProductCircuit,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> (Self, Scalar, Vec<Scalar>) {
     let mut proof: Vec<LayerProof> = Vec::new();
     let num_layers = circuit.left_vec.len();
@@ -198,11 +200,11 @@ impl ProductCircuitEvalProof {
         transcript,
       );
 
-      transcript.append_scalar(b"claim_prod_left", &claims_prod[0]);
-      transcript.append_scalar(b"claim_prod_right", &claims_prod[1]);
+      transcript.append_scalar(&claims_prod[0]);
+      transcript.append_scalar(&claims_prod[1]);
 
       // produce a random challenge
-      let r_layer = transcript.challenge_scalar(b"challenge_r_layer");
+      let r_layer = transcript.challenge_scalar();
       claim = claims_prod[0] + r_layer * (claims_prod[1] - claims_prod[0]);
 
       let mut ext = vec![r_layer];
@@ -222,7 +224,7 @@ impl ProductCircuitEvalProof {
     &self,
     eval: Scalar,
     len: usize,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> (Scalar, Vec<Scalar>) {
     let num_layers = len.log_2();
     let mut claim = eval;
@@ -233,8 +235,8 @@ impl ProductCircuitEvalProof {
       let (claim_last, rand_prod) = self.proof[i].verify(claim, num_rounds, 3, transcript);
 
       let claims_prod = &self.proof[i].claims;
-      transcript.append_scalar(b"claim_prod_left", &claims_prod[0]);
-      transcript.append_scalar(b"claim_prod_right", &claims_prod[1]);
+      transcript.append_scalar(&claims_prod[0]);
+      transcript.append_scalar(&claims_prod[1]);
 
       assert_eq!(rand.len(), rand_prod.len());
       let eq: Scalar = (0..rand.len())
@@ -245,7 +247,7 @@ impl ProductCircuitEvalProof {
       assert_eq!(claims_prod[0] * claims_prod[1] * eq, claim_last);
 
       // produce a random challenge
-      let r_layer = transcript.challenge_scalar(b"challenge_r_layer");
+      let r_layer = transcript.challenge_scalar();
       claim = (Scalar::one() - r_layer) * claims_prod[0] + r_layer * claims_prod[1];
       let mut ext = vec![r_layer];
       ext.extend(rand_prod);
@@ -260,7 +262,7 @@ impl ProductCircuitEvalProofBatched {
   pub fn prove(
     prod_circuit_vec: &mut Vec<&mut ProductCircuit>,
     dotp_circuit_vec: &mut Vec<&mut DotProductCircuit>,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> (Self, Vec<Scalar>) {
     assert!(!prod_circuit_vec.is_empty());
 
@@ -324,8 +326,7 @@ impl ProductCircuitEvalProofBatched {
       );
 
       // produce a fresh set of coeffs and a joint claim
-      let coeff_vec =
-        transcript.challenge_vector(b"rand_coeffs_next_layer", claims_to_verify.len());
+      let coeff_vec = transcript.challenge_vector(claims_to_verify.len());
       let claim = (0..claims_to_verify.len())
         .map(|i| claims_to_verify[i] * coeff_vec[i])
         .sum();
@@ -342,22 +343,22 @@ impl ProductCircuitEvalProofBatched {
 
       let (claims_prod_left, claims_prod_right, _claims_eq) = claims_prod;
       for i in 0..prod_circuit_vec.len() {
-        transcript.append_scalar(b"claim_prod_left", &claims_prod_left[i]);
-        transcript.append_scalar(b"claim_prod_right", &claims_prod_right[i]);
+        transcript.append_scalar(&claims_prod_left[i]);
+        transcript.append_scalar(&claims_prod_right[i]);
       }
 
       if layer_id == 0 && !dotp_circuit_vec.is_empty() {
         let (claims_dotp_left, claims_dotp_right, claims_dotp_weight) = claims_dotp;
         for i in 0..dotp_circuit_vec.len() {
-          transcript.append_scalar(b"claim_dotp_left", &claims_dotp_left[i]);
-          transcript.append_scalar(b"claim_dotp_right", &claims_dotp_right[i]);
-          transcript.append_scalar(b"claim_dotp_weight", &claims_dotp_weight[i]);
+          transcript.append_scalar(&claims_dotp_left[i]);
+          transcript.append_scalar(&claims_dotp_right[i]);
+          transcript.append_scalar(&claims_dotp_weight[i]);
         }
         claims_dotp_final = (claims_dotp_left, claims_dotp_right, claims_dotp_weight);
       }
 
       // produce a random challenge to condense two claims into a single claim
-      let r_layer = transcript.challenge_scalar(b"challenge_r_layer");
+      let r_layer = transcript.challenge_scalar();
 
       claims_to_verify = (0..prod_circuit_vec.len())
         .map(|i| claims_prod_left[i] + r_layer * (claims_prod_right[i] - claims_prod_left[i]))
@@ -388,7 +389,7 @@ impl ProductCircuitEvalProofBatched {
     claims_prod_vec: &[Scalar],
     claims_dotp_vec: &[Scalar],
     len: usize,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> (Vec<Scalar>, Vec<Scalar>, Vec<Scalar>) {
     let num_layers = len.log_2();
     let mut rand: Vec<Scalar> = Vec::new();
@@ -403,8 +404,7 @@ impl ProductCircuitEvalProofBatched {
       }
 
       // produce random coefficients, one for each instance
-      let coeff_vec =
-        transcript.challenge_vector(b"rand_coeffs_next_layer", claims_to_verify.len());
+      let coeff_vec = transcript.challenge_vector(claims_to_verify.len());
 
       // produce a joint claim
       let claim = (0..claims_to_verify.len())
@@ -419,8 +419,8 @@ impl ProductCircuitEvalProofBatched {
       assert_eq!(claims_prod_right.len(), claims_prod_vec.len());
 
       for i in 0..claims_prod_vec.len() {
-        transcript.append_scalar(b"claim_prod_left", &claims_prod_left[i]);
-        transcript.append_scalar(b"claim_prod_right", &claims_prod_right[i]);
+        transcript.append_scalar(&claims_prod_left[i]);
+        transcript.append_scalar(&claims_prod_right[i]);
       }
 
       assert_eq!(rand.len(), rand_prod.len());
@@ -438,9 +438,9 @@ impl ProductCircuitEvalProofBatched {
         let num_prod_instances = claims_prod_vec.len();
         let (claims_dotp_left, claims_dotp_right, claims_dotp_weight) = &self.claims_dotp;
         for i in 0..claims_dotp_left.len() {
-          transcript.append_scalar(b"claim_dotp_left", &claims_dotp_left[i]);
-          transcript.append_scalar(b"claim_dotp_right", &claims_dotp_right[i]);
-          transcript.append_scalar(b"claim_dotp_weight", &claims_dotp_weight[i]);
+          transcript.append_scalar(&claims_dotp_left[i]);
+          transcript.append_scalar(&claims_dotp_right[i]);
+          transcript.append_scalar(&claims_dotp_weight[i]);
 
           claim_expected += coeff_vec[i + num_prod_instances]
             * claims_dotp_left[i]
@@ -452,7 +452,7 @@ impl ProductCircuitEvalProofBatched {
       assert_eq!(claim_expected, claim_last);
 
       // produce a random challenge
-      let r_layer = transcript.challenge_scalar(b"challenge_r_layer");
+      let r_layer = transcript.challenge_scalar();
 
       claims_to_verify = (0..claims_prod_left.len())
         .map(|i| claims_prod_left[i] + r_layer * (claims_prod_right[i] - claims_prod_left[i]))

src/r1csinstance.rs

@@ -1,3 +1,4 @@
+use crate::poseidon_transcript::{AppendToPoseidon, PoseidonTranscript};
 use crate::transcript::AppendToTranscript;
 
 use super::dense_mlpoly::DensePolynomial;
@@ -63,6 +64,15 @@ impl AppendToTranscript for R1CSCommitment {
   }
 }
 
+impl AppendToPoseidon for R1CSCommitment {
+  fn append_to_poseidon(&self, transcript: &mut PoseidonTranscript) {
+    transcript.append_u64(self.num_cons as u64);
+    transcript.append_u64(self.num_vars as u64);
+    transcript.append_u64(self.num_inputs as u64);
+    self.comm.append_to_poseidon(transcript);
+  }
+}
+
 pub struct R1CSDecommitment {
   dense: MultiSparseMatPolynomialAsDense,
 }
@@ -328,7 +338,7 @@ impl R1CSEvalProof {
     ry: &[Scalar],
     evals: &(Scalar, Scalar, Scalar),
     gens: &R1CSCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
   ) -> R1CSEvalProof {
     let timer = Timer::new("R1CSEvalProof::prove");
@@ -353,7 +363,7 @@ impl R1CSEvalProof {
     ry: &[Scalar],
     evals: &(Scalar, Scalar, Scalar),
     gens: &R1CSCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> Result<(), ProofVerifyError> {
     self.proof.verify(
       &comm.comm,

src/r1csproof.rs

@@ -16,7 +16,6 @@ use super::r1csinstance::R1CSInstance;
 use super::random::RandomTape;
 use super::scalar::Scalar;
 use super::sparse_mlpoly::{SparsePolyEntry, SparsePolynomial};
-use super::sumcheck::ZKSumcheckInstanceProof;
 use super::timer::Timer;
 use super::transcript::{AppendToTranscript, ProofTranscript};
 use ark_ec::ProjectiveCurve;
@@ -80,7 +79,7 @@ impl R1CSProof {
     evals_Az: &mut DensePolynomial,
     evals_Bz: &mut DensePolynomial,
     evals_Cz: &mut DensePolynomial,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> (SumcheckInstanceProof, Vec<Scalar>, Vec<Scalar>) {
     let comb_func =
       |poly_tau_comp: &Scalar,
@@ -108,7 +107,7 @@ impl R1CSProof {
     claim: &Scalar,
     evals_z: &mut DensePolynomial,
     evals_ABC: &mut DensePolynomial,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> (SumcheckInstanceProof, Vec<Scalar>, Vec<Scalar>) {
     let comb_func =
       |poly_A_comp: &Scalar, poly_B_comp: &Scalar| -> Scalar { (*poly_A_comp) * poly_B_comp };
@@ -128,16 +127,14 @@ impl R1CSProof {
     vars: Vec<Scalar>,
     input: &[Scalar],
     gens: &R1CSGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
   ) -> (R1CSProof, Vec<Scalar>, Vec<Scalar>) {
     let timer_prove = Timer::new("R1CSProof::prove");
-    transcript.append_protocol_name(R1CSProof::protocol_name());
-
     // we currently require the number of |inputs| + 1 to be at most number of vars
     assert!(input.len() < vars.len());
 
-    input.append_to_transcript(b"input", transcript);
+    transcript.append_scalar_vector(&input.to_vec());
 
     let poly_vars = DensePolynomial::new(vars.clone());
 
@@ -155,8 +152,9 @@ impl R1CSProof {
     };
 
     // derive the verifier's challenge tau
-    let (num_rounds_x, num_rounds_y) = (inst.get_num_cons().log_2(), z.len().log_2());
-    let tau = transcript.challenge_vector(b"challenge_tau", num_rounds_x);
+    let (num_rounds_x, num_rounds_y) =
+      (inst.get_num_cons().log2() as usize, z.len().log2() as usize);
+    let tau = transcript.challenge_vector(num_rounds_x);
     // compute the initial evaluation table for R(\tau, x)
     let mut poly_tau = DensePolynomial::new(EqPolynomial::new(tau).evals());
     let (mut poly_Az, mut poly_Bz, mut poly_Cz) =
@@ -186,9 +184,9 @@ impl R1CSProof {
 
     let timer_sc_proof_phase2 = Timer::new("prove_sc_phase_two");
     // combine the three claims into a single claim
-    let r_A = transcript.challenge_scalar(b"challenege_Az");
-    let r_B = transcript.challenge_scalar(b"challenege_Bz");
-    let r_C = transcript.challenge_scalar(b"challenege_Cz");
+    let r_A = transcript.challenge_scalar();
+    let r_B = transcript.challenge_scalar();
+    let r_C = transcript.challenge_scalar();
     let claim_phase2 = r_A * Az_claim + r_B * Bz_claim + r_C * Cz_claim;
 
     let evals_ABC = {
@@ -238,19 +236,21 @@ impl R1CSProof {
     num_cons: usize,
     input: &[Scalar],
     evals: &(Scalar, Scalar, Scalar),
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     gens: &R1CSGens,
   ) -> Result<(Vec<Scalar>, Vec<Scalar>), ProofVerifyError> {
-    transcript.append_protocol_name(R1CSProof::protocol_name());
+    // transcript.append_protocol_name(R1CSProof::protocol_name());
 
-    input.append_to_transcript(b"input", transcript);
+    for i in 0..input.len() {
+      transcript.append_scalar(&input[i]);
+    }
 
     let n = num_vars;
 
     let (num_rounds_x, num_rounds_y) = (num_cons.log_2(), (2 * num_vars).log_2());
 
     // derive the verifier's challenge tau
-    let tau = transcript.challenge_vector(b"challenge_tau", num_rounds_x);
+    let tau = transcript.challenge_vector(num_rounds_x);
 
     // verify the first sum-check instance
     let claim_phase1 = Scalar::zero();
@@ -271,9 +271,9 @@ impl R1CSProof {
     assert_eq!(claim_post_phase1, expected_claim_post_phase1);
 
     // derive three public challenges and then derive a joint claim
-    let r_A = transcript.challenge_scalar(b"challenege_Az");
-    let r_B = transcript.challenge_scalar(b"challenege_Bz");
-    let r_C = transcript.challenge_scalar(b"challenege_Cz");
+    let r_A = transcript.challenge_scalar();
+    let r_B = transcript.challenge_scalar();
+    let r_C = transcript.challenge_scalar();
 
     let claim_phase2 = r_A * Az_claim + r_B * Bz_claim + r_C * Cz_claim;
 
@@ -310,6 +310,8 @@ impl R1CSProof {
 
 #[cfg(test)]
 mod tests {
+  use crate::parameters::poseidon_params;
+
   use super::*;
   use ark_std::UniformRand;
   use test::Bencher;
@@ -394,8 +396,10 @@ mod tests {
 
     let gens = R1CSGens::new(b"test-m", num_cons, num_vars);
 
+    let params = poseidon_params();
     let mut random_tape = RandomTape::new(b"proof");
-    let mut prover_transcript = Transcript::new(b"example");
+    // let mut prover_transcript = PoseidonTranscript::new(&params);
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let (proof, rx, ry) = R1CSProof::prove(
       &inst,
       vars,
@@ -407,7 +411,8 @@ mod tests {
 
     let inst_evals = inst.evaluate(&rx, &ry);
 
-    let mut verifier_transcript = Transcript::new(b"example");
+    // let mut verifier_transcript = PoseidonTranscript::new(&params);
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
     assert!(proof
       .verify(
         inst.get_num_vars(),

src/sparse_mlpoly.rs

@@ -1,6 +1,8 @@
 #![allow(clippy::type_complexity)]
 #![allow(clippy::too_many_arguments)]
 #![allow(clippy::needless_range_loop)]
+use crate::poseidon_transcript::{AppendToPoseidon, PoseidonTranscript};
+
 use super::dense_mlpoly::DensePolynomial;
 use super::dense_mlpoly::{
   EqPolynomial, IdentityPolynomial, PolyCommitment, PolyCommitmentGens, PolyEvalProof,
@@ -12,10 +14,10 @@ use super::random::RandomTape;
 use super::scalar::Scalar;
 use super::timer::Timer;
 use super::transcript::{AppendToTranscript, ProofTranscript};
+use ark_ff::{Field, One, Zero};
+use ark_serialize::*;
 use core::cmp::Ordering;
 use merlin::Transcript;
-use ark_serialize::*;
-use ark_ff::{One, Zero, Field};
 
 #[derive(Debug, CanonicalSerialize, CanonicalDeserialize)]
 pub struct SparseMatEntry {
@@ -87,18 +89,18 @@ impl DerefsEvalProof {
     r: &[Scalar],
     evals: Vec<Scalar>,
     gens: &PolyCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
   ) -> PolyEvalProof {
     assert_eq!(joint_poly.get_num_vars(), r.len() + evals.len().log_2());
 
     // append the claimed evaluations to transcript
-    evals.append_to_transcript(b"evals_ops_val", transcript);
+    // evals.append_to_transcript(b"evals_ops_val", transcript);
+    transcript.append_scalar_vector(&evals);
 
     // n-to-1 reduction
     let (r_joint, eval_joint) = {
-      let challenges =
-        transcript.challenge_vector(b"challenge_combine_n_to_one", evals.len().log_2());
+      let challenges = transcript.challenge_vector(evals.len().log2());
       let mut poly_evals = DensePolynomial::new(evals);
       for i in (0..challenges.len()).rev() {
         poly_evals.bound_poly_var_bot(&challenges[i]);
@@ -112,7 +114,7 @@ impl DerefsEvalProof {
       (r_joint, joint_claim_eval)
     };
     // decommit the joint polynomial at r_joint
-    eval_joint.append_to_transcript(b"joint_claim_eval", transcript);
+    transcript.append_scalar(&eval_joint);
     let (proof_derefs, _comm_derefs_eval) = PolyEvalProof::prove(
       joint_poly,
       None,
@@ -134,10 +136,10 @@ impl DerefsEvalProof {
     eval_col_ops_val_vec: &[Scalar],
     r: &[Scalar],
     gens: &PolyCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
   ) -> Self {
-    transcript.append_protocol_name(DerefsEvalProof::protocol_name());
+    // transcript.append_protocol_name(DerefsEvalProof::protocol_name());
 
     let evals = {
       let mut evals = eval_row_ops_val_vec.to_owned();
@@ -157,14 +159,14 @@ impl DerefsEvalProof {
     r: &[Scalar],
     evals: Vec<Scalar>,
     gens: &PolyCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> Result<(), ProofVerifyError> {
     // append the claimed evaluations to transcript
-    evals.append_to_transcript(b"evals_ops_val", transcript);
+    // evals.append_to_transcript(b"evals_ops_val", transcript);
+    transcript.append_scalar_vector(&evals);
 
     // n-to-1 reduction
-    let challenges =
-      transcript.challenge_vector(b"challenge_combine_n_to_one", evals.len().log_2());
+    let challenges = transcript.challenge_vector(evals.len().log2());
     let mut poly_evals = DensePolynomial::new(evals);
     for i in (0..challenges.len()).rev() {
       poly_evals.bound_poly_var_bot(&challenges[i]);
@@ -175,7 +177,8 @@ impl DerefsEvalProof {
     r_joint.extend(r);
 
     // decommit the joint polynomial at r_joint
-    joint_claim_eval.append_to_transcript(b"joint_claim_eval", transcript);
+    // joint_claim_eval.append_to_transcript(b"joint_claim_eval", transcript);
+    transcript.append_scalar(&joint_claim_eval);
 
     proof.verify_plain(gens, transcript, &r_joint, &joint_claim_eval, comm)
   }
@@ -188,9 +191,9 @@ impl DerefsEvalProof {
     eval_col_ops_val_vec: &[Scalar],
     gens: &PolyCommitmentGens,
     comm: &DerefsCommitment,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> Result<(), ProofVerifyError> {
-    transcript.append_protocol_name(DerefsEvalProof::protocol_name());
+    // transcript.append_protocol_name(DerefsEvalProof::protocol_name());
     let mut evals = eval_row_ops_val_vec.to_owned();
     evals.extend(eval_col_ops_val_vec);
     evals.resize(evals.len().next_power_of_two(), Scalar::zero());
@@ -214,6 +217,11 @@ impl AppendToTranscript for DerefsCommitment {
   }
 }
 
+impl AppendToPoseidon for DerefsCommitment {
+  fn append_to_poseidon(&self, transcript: &mut PoseidonTranscript) {
+    self.comm_ops_val.append_to_poseidon(transcript);
+  }
+}
 struct AddrTimestamps {
   ops_addr_usize: Vec<Vec<usize>>,
   ops_addr: Vec<DensePolynomial>,
@@ -342,6 +350,16 @@ impl AppendToTranscript for SparseMatPolyCommitment {
   }
 }
 
+impl AppendToPoseidon for SparseMatPolyCommitment {
+  fn append_to_poseidon(&self, transcript: &mut PoseidonTranscript) {
+    transcript.append_u64(self.batch_size as u64);
+    transcript.append_u64(self.num_ops as u64);
+    transcript.append_u64(self.num_mem_cells as u64);
+    self.comm_comb_ops.append_to_poseidon(transcript);
+    self.comm_comb_mem.append_to_poseidon(transcript);
+  }
+}
+
 impl SparseMatPolynomial {
   pub fn new(num_vars_x: usize, num_vars_y: usize, M: Vec<SparseMatEntry>) -> Self {
     SparseMatPolynomial {
@@ -465,7 +483,7 @@ impl SparseMatPolynomial {
         let val = &self.M[i].val;
         (row, z[col] * val)
       })
-      .fold(vec![Scalar::zero(); num_rows], |mut  Mz, (r, v)| {
+      .fold(vec![Scalar::zero(); num_rows], |mut Mz, (r, v)| {
         Mz[r] += v;
         Mz
       })
@@ -732,10 +750,10 @@ impl HashLayerProof {
     dense: &MultiSparseMatPolynomialAsDense,
     derefs: &Derefs,
     gens: &SparseMatPolyCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
   ) -> Self {
-    transcript.append_protocol_name(HashLayerProof::protocol_name());
+    // transcript.append_protocol_name(HashLayerProof::protocol_name());
 
     let (rand_mem, rand_ops) = rand;
 
@@ -775,9 +793,8 @@ impl HashLayerProof {
     evals_ops.extend(&eval_col_read_ts_vec);
     evals_ops.extend(&eval_val_vec);
     evals_ops.resize(evals_ops.len().next_power_of_two(), Scalar::zero());
-    evals_ops.append_to_transcript(b"claim_evals_ops", transcript);
-    let challenges_ops =
-      transcript.challenge_vector(b"challenge_combine_n_to_one", evals_ops.len().log_2());
+    transcript.append_scalar_vector(&evals_ops);
+    let challenges_ops = transcript.challenge_vector(evals_ops.len().log2());
 
     let mut poly_evals_ops = DensePolynomial::new(evals_ops);
     for i in (0..challenges_ops.len()).rev() {
@@ -788,7 +805,7 @@ impl HashLayerProof {
     let mut r_joint_ops = challenges_ops;
     r_joint_ops.extend(rand_ops);
     debug_assert_eq!(dense.comb_ops.evaluate(&r_joint_ops), joint_claim_eval_ops);
-    joint_claim_eval_ops.append_to_transcript(b"joint_claim_eval_ops", transcript);
+    transcript.append_scalar(&joint_claim_eval_ops);
     let (proof_ops, _comm_ops_eval) = PolyEvalProof::prove(
       &dense.comb_ops,
       None,
@@ -802,9 +819,9 @@ impl HashLayerProof {
 
     // form a single decommitment using comb_comb_mem at rand_mem
     let evals_mem: Vec<Scalar> = vec![eval_row_audit_ts, eval_col_audit_ts];
-    evals_mem.append_to_transcript(b"claim_evals_mem", transcript);
-    let challenges_mem =
-      transcript.challenge_vector(b"challenge_combine_two_to_one", evals_mem.len().log_2());
+    // evals_mem.append_to_transcript(b"claim_evals_mem", transcript);
+    transcript.append_scalar_vector(&evals_mem);
+    let challenges_mem = transcript.challenge_vector(evals_mem.len().log2());
 
     let mut poly_evals_mem = DensePolynomial::new(evals_mem);
     for i in (0..challenges_mem.len()).rev() {
@@ -815,7 +832,7 @@ impl HashLayerProof {
     let mut r_joint_mem = challenges_mem;
     r_joint_mem.extend(rand_mem);
     debug_assert_eq!(dense.comb_mem.evaluate(&r_joint_mem), joint_claim_eval_mem);
-    joint_claim_eval_mem.append_to_transcript(b"joint_claim_eval_mem", transcript);
+    transcript.append_scalar(&joint_claim_eval_mem);
     let (proof_mem, _comm_mem_eval) = PolyEvalProof::prove(
       &dense.comb_mem,
       None,
@@ -902,10 +919,10 @@ impl HashLayerProof {
     ry: &[Scalar],
     r_hash: &Scalar,
     r_multiset_check: &Scalar,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> Result<(), ProofVerifyError> {
     let timer = Timer::new("verify_hash_proof");
-    transcript.append_protocol_name(HashLayerProof::protocol_name());
+    // transcript.append_protocol_name(HashLayerProof::protocol_name());
 
     let (rand_mem, rand_ops) = rand;
 
@@ -945,9 +962,9 @@ impl HashLayerProof {
     evals_ops.extend(eval_col_read_ts_vec);
     evals_ops.extend(eval_val_vec);
     evals_ops.resize(evals_ops.len().next_power_of_two(), Scalar::zero());
-    evals_ops.append_to_transcript(b"claim_evals_ops", transcript);
-    let challenges_ops =
-      transcript.challenge_vector(b"challenge_combine_n_to_one", evals_ops.len().log_2());
+    transcript.append_scalar_vector(&evals_ops);
+    // evals_ops.append_to_transcript(b"claim_evals_ops", transcript);
+    let challenges_ops = transcript.challenge_vector(evals_ops.len().log2());
 
     let mut poly_evals_ops = DensePolynomial::new(evals_ops);
     for i in (0..challenges_ops.len()).rev() {
@@ -957,21 +974,24 @@ impl HashLayerProof {
     let joint_claim_eval_ops = poly_evals_ops[0];
     let mut r_joint_ops = challenges_ops;
     r_joint_ops.extend(rand_ops);
-    joint_claim_eval_ops.append_to_transcript(b"joint_claim_eval_ops", transcript);
-    self.proof_ops.verify_plain(
-      &gens.gens_ops,
-      transcript,
-      &r_joint_ops,
-      &joint_claim_eval_ops,
-      &comm.comm_comb_ops,
-    )?;
+    transcript.append_scalar(&joint_claim_eval_ops);
+    assert!(self
+      .proof_ops
+      .verify_plain(
+        &gens.gens_ops,
+        transcript,
+        &r_joint_ops,
+        &joint_claim_eval_ops,
+        &comm.comm_comb_ops
+      )
+      .is_ok());
 
     // verify proof-mem using comm_comb_mem at rand_mem
     // form a single decommitment using comb_comb_mem at rand_mem
     let evals_mem: Vec<Scalar> = vec![*eval_row_audit_ts, *eval_col_audit_ts];
-    evals_mem.append_to_transcript(b"claim_evals_mem", transcript);
-    let challenges_mem =
-      transcript.challenge_vector(b"challenge_combine_two_to_one", evals_mem.len().log_2());
+    // evals_mem.append_to_transcript(b"claim_evals_mem", transcript);
+    transcript.append_scalar_vector(&evals_mem);
+    let challenges_mem = transcript.challenge_vector(evals_mem.len().log2());
 
     let mut poly_evals_mem = DensePolynomial::new(evals_mem);
     for i in (0..challenges_mem.len()).rev() {
@@ -981,7 +1001,8 @@ impl HashLayerProof {
     let joint_claim_eval_mem = poly_evals_mem[0];
     let mut r_joint_mem = challenges_mem;
     r_joint_mem.extend(rand_mem);
-    joint_claim_eval_mem.append_to_transcript(b"joint_claim_eval_mem", transcript);
+    // joint_claim_eval_mem.append_to_transcript(b"joint_claim_eval_mem", transcript);
+    transcript.append_scalar(&joint_claim_eval_mem);
     self.proof_mem.verify_plain(
       &gens.gens_mem,
       transcript,
@@ -1042,9 +1063,9 @@ impl ProductLayerProof {
     dense: &MultiSparseMatPolynomialAsDense,
     derefs: &Derefs,
     eval: &[Scalar],
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> (Self, Vec<Scalar>, Vec<Scalar>) {
-    transcript.append_protocol_name(ProductLayerProof::protocol_name());
+    // transcript.append_protocol_name(ProductLayerProof::protocol_name());
 
     let row_eval_init = row_prod_layer.init.evaluate();
     let row_eval_audit = row_prod_layer.audit.evaluate();
@@ -1062,10 +1083,10 @@ impl ProductLayerProof {
     let rs: Scalar = (0..row_eval_read.len()).map(|i| row_eval_read[i]).product();
     assert_eq!(row_eval_init * ws, rs * row_eval_audit);
 
-    row_eval_init.append_to_transcript(b"claim_row_eval_init", transcript);
-    row_eval_read.append_to_transcript(b"claim_row_eval_read", transcript);
-    row_eval_write.append_to_transcript(b"claim_row_eval_write", transcript);
-    row_eval_audit.append_to_transcript(b"claim_row_eval_audit", transcript);
+    transcript.append_scalar(&row_eval_init);
+    transcript.append_scalar_vector(&row_eval_read);
+    transcript.append_scalar_vector(&row_eval_write);
+    transcript.append_scalar(&row_eval_audit);
 
     let col_eval_init = col_prod_layer.init.evaluate();
     let col_eval_audit = col_prod_layer.audit.evaluate();
@@ -1083,10 +1104,10 @@ impl ProductLayerProof {
     let rs: Scalar = (0..col_eval_read.len()).map(|i| col_eval_read[i]).product();
     assert_eq!(col_eval_init * ws, rs * col_eval_audit);
 
-    col_eval_init.append_to_transcript(b"claim_col_eval_init", transcript);
-    col_eval_read.append_to_transcript(b"claim_col_eval_read", transcript);
-    col_eval_write.append_to_transcript(b"claim_col_eval_write", transcript);
-    col_eval_audit.append_to_transcript(b"claim_col_eval_audit", transcript);
+    transcript.append_scalar(&col_eval_init);
+    transcript.append_scalar_vector(&col_eval_read);
+    transcript.append_scalar_vector(&col_eval_write);
+    transcript.append_scalar(&col_eval_audit);
 
     // prepare dotproduct circuit for batching then with ops-related product circuits
     assert_eq!(eval.len(), derefs.row_ops_val.len());
@@ -1109,8 +1130,10 @@ impl ProductLayerProof {
       let (eval_dotp_left, eval_dotp_right) =
         (dotp_circuit_left.evaluate(), dotp_circuit_right.evaluate());
 
-      eval_dotp_left.append_to_transcript(b"claim_eval_dotp_left", transcript);
-      eval_dotp_right.append_to_transcript(b"claim_eval_dotp_right", transcript);
+      // eval_dotp_left.append_to_transcript(b"claim_eval_dotp_left", transcript);
+      // eval_dotp_right.append_to_transcript(b"claim_eval_dotp_right", transcript);
+      transcript.append_scalar(&eval_dotp_left);
+      transcript.append_scalar(&eval_dotp_right);
       assert_eq!(eval_dotp_left + eval_dotp_right, eval[i]);
       eval_dotp_left_vec.push(eval_dotp_left);
       eval_dotp_right_vec.push(eval_dotp_right);
@@ -1207,7 +1230,9 @@ impl ProductLayerProof {
     };
 
     let mut product_layer_proof_encoded: Vec<u8> = Vec::new();
-    product_layer_proof.serialize(&mut product_layer_proof_encoded).unwrap();
+    product_layer_proof
+      .serialize(&mut product_layer_proof_encoded)
+      .unwrap();
     let msg = format!(
       "len_product_layer_proof {:?}",
       product_layer_proof_encoded.len()
@@ -1222,7 +1247,7 @@ impl ProductLayerProof {
     num_ops: usize,
     num_cells: usize,
     eval: &[Scalar],
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> Result<
     (
       Vec<Scalar>,
@@ -1233,7 +1258,7 @@ impl ProductLayerProof {
     ),
     ProofVerifyError,
   > {
-    transcript.append_protocol_name(ProductLayerProof::protocol_name());
+    // transcript.append_protocol_name(ProductLayerProof::protocol_name());
 
     let timer = Timer::new("verify_prod_proof");
     let num_instances = eval.len();
@@ -1246,12 +1271,17 @@ impl ProductLayerProof {
       .map(|i| row_eval_write[i])
       .product();
     let rs: Scalar = (0..row_eval_read.len()).map(|i| row_eval_read[i]).product();
-    assert_eq!( ws * row_eval_init , rs * row_eval_audit);
+    assert_eq!(ws * row_eval_init, rs * row_eval_audit);
+
+    // row_eval_init.append_to_transcript(b"claim_row_eval_init", transcript);
+    // row_eval_read.append_to_transcript(b"claim_row_eval_read", transcript);
+    // row_eval_write.append_to_transcript(b"claim_row_eval_write", transcript);
+    // row_eval_audit.append_to_transcript(b"claim_row_eval_audit", transcript);
 
-    row_eval_init.append_to_transcript(b"claim_row_eval_init", transcript);
-    row_eval_read.append_to_transcript(b"claim_row_eval_read", transcript);
-    row_eval_write.append_to_transcript(b"claim_row_eval_write", transcript);
-    row_eval_audit.append_to_transcript(b"claim_row_eval_audit", transcript);
+    transcript.append_scalar(row_eval_init);
+    transcript.append_scalar_vector(row_eval_read);
+    transcript.append_scalar_vector(row_eval_write);
+    transcript.append_scalar(row_eval_audit);
 
     // subset check
     let (col_eval_init, col_eval_read, col_eval_write, col_eval_audit) = &self.eval_col;
@@ -1263,10 +1293,15 @@ impl ProductLayerProof {
     let rs: Scalar = (0..col_eval_read.len()).map(|i| col_eval_read[i]).product();
     assert_eq!(ws * col_eval_init, rs * col_eval_audit);
 
-    col_eval_init.append_to_transcript(b"claim_col_eval_init", transcript);
-    col_eval_read.append_to_transcript(b"claim_col_eval_read", transcript);
-    col_eval_write.append_to_transcript(b"claim_col_eval_write", transcript);
-    col_eval_audit.append_to_transcript(b"claim_col_eval_audit", transcript);
+    // col_eval_init.append_to_transcript(b"claim_col_eval_init", transcript);
+    // col_eval_read.append_to_transcript(b"claim_col_eval_read", transcript);
+    // col_eval_write.append_to_transcript(b"claim_col_eval_write", transcript);
+    // col_eval_audit.append_to_transcript(b"claim_col_eval_audit", transcript);
+
+    transcript.append_scalar(col_eval_init);
+    transcript.append_scalar_vector(col_eval_read);
+    transcript.append_scalar_vector(col_eval_write);
+    transcript.append_scalar(col_eval_audit);
 
     // verify the evaluation of the sparse polynomial
     let (eval_dotp_left, eval_dotp_right) = &self.eval_val;
@@ -1275,8 +1310,10 @@ impl ProductLayerProof {
     let mut claims_dotp_circuit: Vec<Scalar> = Vec::new();
     for i in 0..num_instances {
       assert_eq!(eval_dotp_left[i] + eval_dotp_right[i], eval[i]);
-      eval_dotp_left[i].append_to_transcript(b"claim_eval_dotp_left", transcript);
-      eval_dotp_right[i].append_to_transcript(b"claim_eval_dotp_right", transcript);
+      // eval_dotp_left[i].append_to_transcript(b"claim_eval_dotp_left", transcript);
+      // eval_dotp_right[i].append_to_transcript(b"claim_eval_dotp_right", transcript)
+      transcript.append_scalar(&eval_dotp_left[i]);
+      transcript.append_scalar(&eval_dotp_right[i]);
 
       claims_dotp_circuit.push(eval_dotp_left[i]);
       claims_dotp_circuit.push(eval_dotp_right[i]);
@@ -1330,10 +1367,10 @@ impl PolyEvalNetworkProof {
     derefs: &Derefs,
     evals: &[Scalar],
     gens: &SparseMatPolyCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
   ) -> Self {
-    transcript.append_protocol_name(PolyEvalNetworkProof::protocol_name());
+    // transcript.append_protocol_name(PolyEvalNetworkProof::protocol_name());
 
     let (proof_prod_layer, rand_mem, rand_ops) = ProductLayerProof::prove(
       &mut network.row_layers.prod_layer,
@@ -1370,10 +1407,10 @@ impl PolyEvalNetworkProof {
     ry: &[Scalar],
     r_mem_check: &(Scalar, Scalar),
     nz: usize,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> Result<(), ProofVerifyError> {
     let timer = Timer::new("verify_polyeval_proof");
-    transcript.append_protocol_name(PolyEvalNetworkProof::protocol_name());
+    // transcript.append_protocol_name(PolyEvalNetworkProof::protocol_name());
 
     let num_instances = evals.len();
     let (r_hash, r_multiset_check) = r_mem_check;
@@ -1459,10 +1496,10 @@ impl SparseMatPolyEvalProof {
     ry: &[Scalar],
     evals: &[Scalar], // a vector evaluation of \widetilde{M}(r = (rx,ry)) for each M
     gens: &SparseMatPolyCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
     random_tape: &mut RandomTape,
   ) -> SparseMatPolyEvalProof {
-    transcript.append_protocol_name(SparseMatPolyEvalProof::protocol_name());
+    // transcript.append_protocol_name(SparseMatPolyEvalProof::protocol_name());
 
     // ensure there is one eval for each polynomial in dense
     assert_eq!(evals.len(), dense.batch_size);
@@ -1481,14 +1518,14 @@ impl SparseMatPolyEvalProof {
     let timer_commit = Timer::new("commit_nondet_witness");
     let comm_derefs = {
       let comm = derefs.commit(&gens.gens_derefs);
-      comm.append_to_transcript(b"comm_poly_row_col_ops_val", transcript);
+      comm.append_to_poseidon(transcript);
       comm
     };
     timer_commit.stop();
 
     let poly_eval_network_proof = {
       // produce a random element from the transcript for hash function
-      let r_mem_check = transcript.challenge_vector(b"challenge_r_hash", 2);
+      let r_mem_check = transcript.challenge_vector(2);
 
       // build a network to evaluate the sparse polynomial
       let timer_build_network = Timer::new("build_layered_network");
@@ -1529,9 +1566,9 @@ impl SparseMatPolyEvalProof {
     ry: &[Scalar],
     evals: &[Scalar], // evaluation of \widetilde{M}(r = (rx,ry))
     gens: &SparseMatPolyCommitmentGens,
-    transcript: &mut Transcript,
+    transcript: &mut PoseidonTranscript,
   ) -> Result<(), ProofVerifyError> {
-    transcript.append_protocol_name(SparseMatPolyEvalProof::protocol_name());
+    // transcript.append_protocol_name(SparseMatPolyEvalProof::protocol_name());
 
     // equalize the lengths of rx and ry
     let (rx_ext, ry_ext) = SparseMatPolyEvalProof::equalize(rx, ry);
@@ -1540,12 +1577,10 @@ impl SparseMatPolyEvalProof {
     assert_eq!(rx_ext.len().pow2(), num_mem_cells);
 
     // add claims to transcript and obtain challenges for randomized mem-check circuit
-    self
-      .comm_derefs
-      .append_to_transcript(b"comm_poly_row_col_ops_val", transcript);
+    self.comm_derefs.append_to_poseidon(transcript);
 
     // produce a random element from the transcript for hash function
-    let r_mem_check = transcript.challenge_vector(b"challenge_r_hash", 2);
+    let r_mem_check = transcript.challenge_vector(2);
 
     self.poly_eval_network_proof.verify(
       comm,
@@ -1610,13 +1645,15 @@ impl SparsePolynomial {
 
 #[cfg(test)]
 mod tests {
+  use crate::{commitments::MultiCommitGens, parameters::poseidon_params};
+
   use super::*;
-use ark_std::{UniformRand};
-use rand::RngCore;
+  use ark_std::UniformRand;
+  use rand::RngCore;
 
   #[test]
   fn check_sparse_polyeval_proof() {
-  let mut rng = ark_std::rand::thread_rng();
+    let mut rng = ark_std::rand::thread_rng();
 
     let num_nz_entries: usize = 256;
     let num_rows: usize = 256;
@@ -1628,7 +1665,7 @@ use rand::RngCore;
 
     for _i in 0..num_nz_entries {
       M.push(SparseMatEntry::new(
-        (rng.next_u64()% (num_rows as u64)) as usize,
+        (rng.next_u64() % (num_rows as u64)) as usize,
         (rng.next_u64() % (num_cols as u64)) as usize,
         Scalar::rand(&mut rng),
       ));
@@ -1656,8 +1693,9 @@ use rand::RngCore;
     let eval = SparseMatPolynomial::multi_evaluate(&[&poly_M], &rx, &ry);
     let evals = vec![eval[0], eval[0], eval[0]];
 
+    let params = poseidon_params();
     let mut random_tape = RandomTape::new(b"proof");
-    let mut prover_transcript = Transcript::new(b"example");
+    let mut prover_transcript = PoseidonTranscript::new(&params);
     let proof = SparseMatPolyEvalProof::prove(
       &dense,
       &rx,
@@ -1668,7 +1706,8 @@ use rand::RngCore;
       &mut random_tape,
     );
 
-    let mut verifier_transcript = Transcript::new(b"example");
+    let mut verifier_transcript = PoseidonTranscript::new(&params);
+    (b"example");
     assert!(proof
       .verify(
         &poly_comm,

src/unipoly.rs

@@ -1,10 +1,12 @@
+use crate::poseidon_transcript::{AppendToPoseidon, PoseidonTranscript};
+
 use super::commitments::{Commitments, MultiCommitGens};
 use super::group::GroupElement;
-use super::scalar::{Scalar};
+use super::scalar::Scalar;
 use super::transcript::{AppendToTranscript, ProofTranscript};
-use merlin::Transcript;
+use ark_ff::{Field, One, Zero};
 use ark_serialize::*;
-use ark_ff::{One, Zero, Field};
+use merlin::Transcript;
 // ax^2 + bx + c stored as vec![c,b,a]
 // ax^3 + bx^2 + cx + d stored as vec![d,c,b,a]
 #[derive(Debug)]
@@ -109,6 +111,16 @@ impl CompressedUniPoly {
   }
 }
 
+impl AppendToPoseidon for UniPoly {
+  fn append_to_poseidon(&self, transcript: &mut PoseidonTranscript) {
+    // transcript.append_message(label, b"UniPoly_begin");
+    for i in 0..self.coeffs.len() {
+      transcript.append_scalar(&self.coeffs[i]);
+    }
+    // transcript.append_message(label, b"UniPoly_end");
+  }
+}
+
 impl AppendToTranscript for UniPoly {
   fn append_to_transcript(&self, label: &'static [u8], transcript: &mut Transcript) {
     transcript.append_message(label, b"UniPoly_begin");