@@ -0,0 +1,7 @@
+# ethdos-fold
+
+- run native tests: `cargo test --release -- --nocapture`
+- build wasm: `wasm-pack build --target web`
+- serve the web: `python -m http.server 8080`
+  - go to http://127.0.0.1:8080/index.html
+

@@ -83,7 +83,7 @@ // increment the degree
         degree = degree.clone() + FpVar::<F>::one();
 
         let pk_i1_xy = external_inputs.pk.to_constraint_field()?;
-        Ok(vec![vec![pk_0_x, pk_0_y], pk_i1_xy, vec![degree]].concat())
+        Ok([vec![pk_0_x, pk_0_y], pk_i1_xy, vec![degree]].concat())
     }
 }
 #[cfg(test)]

@@ -0,0 +1,197 @@
+//! This file contains the WASM bindings.
+//!
+#![allow(non_snake_case)]
+#![allow(dead_code)]
+#![allow(non_camel_case_types)]
+#![allow(clippy::upper_case_acronyms)]
+
+use ark_bn254::{Fr, G1Projective as G1};
+use ark_ec::AffineRepr;
+use ark_grumpkin::Projective as G2;
+use ark_serialize::{CanonicalDeserialize, CanonicalSerialize};
+use ark_std::Zero;
+use base64::{engine::general_purpose::STANDARD as b64, Engine as _};
+use rand::rngs::OsRng;
+
+use arkeddsa::ed_on_bn254_twist::{constraints::EdwardsVar, EdwardsProjective};
+
+use folding_schemes::{
+    commitment::pedersen::Pedersen,
+    folding::nova::{Nova, PreprocessorParam},
+    frontend::FCircuit,
+    transcript::poseidon::poseidon_canonical_config,
+    FoldingScheme,
+};
+
+use crate::fcircuit::EthDosCircuit;
+use crate::signature::{gen_signatures, SigPk};
+use crate::utils::{dbg, elapsed, get_time};
+
+mod fcircuit;
+mod fold_ethdos;
+mod signature;
+mod utils;
+
+use wasm_bindgen::prelude::*;
+
+// define type aliases for the FCircuit (FC) and the FoldingScheme (FS), to avoid writting the
+// whole type each time.
+type FC = EthDosCircuit<Fr, EdwardsProjective, EdwardsVar>;
+type FS = Nova<G1, G2, FC, Pedersen<G1>, Pedersen<G2>, false>;
+
+#[wasm_bindgen]
+extern "C" {
+    fn alert(s: &str);
+}
+
+#[wasm_bindgen]
+pub fn gen_params() -> Vec<String> {
+    let mut rng = OsRng;
+    let poseidon_config = poseidon_canonical_config::<Fr>();
+
+    let f_circuit = FC::new(poseidon_config.clone()).unwrap();
+
+    let nova_preprocess_params = PreprocessorParam::new(poseidon_config.clone(), f_circuit.clone());
+    let start = get_time();
+    let nova_params = FS::preprocess(&mut rng, &nova_preprocess_params).unwrap();
+    dbg(format!("Nova params generated: {:?}ms", elapsed(start)));
+
+    // serialize
+    let start = get_time();
+    let mut prover_params_serialized = vec![];
+    nova_params
+        .0
+        .serialize_compressed(&mut prover_params_serialized)
+        .unwrap();
+    dbg(format!(
+        "Nova prover params serialized: {:?}ms",
+        elapsed(start)
+    ));
+
+    let start = get_time();
+    let mut verifier_params_serialized = vec![];
+    nova_params
+        .1
+        .serialize_compressed(&mut verifier_params_serialized)
+        .unwrap();
+    dbg(format!(
+        "Nova prover params serialized: {:?}ms",
+        elapsed(start)
+    ));
+
+    vec![
+        b64.encode(&prover_params_serialized),
+        b64.encode(&prover_params_serialized),
+    ]
+}
+
+#[wasm_bindgen]
+pub fn gen_sigs(n_steps: usize) -> Vec<String> {
+    let mut rng = OsRng;
+    let poseidon_config = poseidon_canonical_config::<Fr>();
+
+    let sigs: Vec<SigPk<EdwardsProjective>> = gen_signatures(&mut rng, &poseidon_config, n_steps);
+    let b: Vec<Vec<u8>> = sigs.iter().map(|&s| s.to_bytes()).collect();
+    b.iter().map(|s| b64.encode(s)).collect::<Vec<String>>()
+}
+
+#[wasm_bindgen]
+pub fn fold_sigs(params: Vec<String>, sigs_pks: Vec<String>) -> String {
+    dbg("starting fold_sigs (rust)".to_string());
+    dbg(format!("received sigs: {:?}", sigs_pks));
+
+    let poseidon_config = poseidon_canonical_config::<Fr>();
+
+    // parse sigs_pks
+    let b: Vec<Vec<u8>> = sigs_pks.iter().map(|s| b64.decode(s).unwrap()).collect();
+    let pks_sigs: Vec<SigPk<EdwardsProjective>> =
+        b.iter().map(|s| SigPk::from_bytes(s.clone())).collect();
+
+    // parse params
+    let start = get_time();
+    let pp = FS::pp_deserialize_with_mode(
+        &mut b64.decode(params[0].clone()).unwrap().as_slice(),
+        ark_serialize::Compress::Yes,
+        ark_serialize::Validate::Yes,
+        poseidon_config.clone(), // fcircuit_params
+    )
+    .unwrap();
+    let vp = FS::vp_deserialize_with_mode(
+        &mut b64.decode(params[1].clone()).unwrap().as_slice(),
+        ark_serialize::Compress::Yes,
+        ark_serialize::Validate::Yes,
+        poseidon_config.clone(), // fcircuit_params
+    )
+    .unwrap();
+    let fs_params = (pp, vp);
+    dbg(format!(
+        "params (prover & verifier) deserialization: {:?}ms",
+        elapsed(start)
+    ));
+
+    // set the initial state
+    let xy = pks_sigs[0].pk.0.xy().unwrap();
+    let pk0 = vec![xy.0, xy.1];
+    let z_0: Vec<Fr> = [pk0.clone(), pk0, vec![Fr::zero()]].concat();
+
+    type FC = EthDosCircuit<Fr, EdwardsProjective, EdwardsVar>;
+    let f_circuit = FC::new(poseidon_config.clone()).unwrap();
+
+    // initialize the folding scheme engine, in our case we use Nova
+    let mut nova = FS::init(&fs_params, f_circuit, z_0.clone()).unwrap();
+    let rng = OsRng;
+    let n_steps = sigs_pks.len();
+
+    let start_full = get_time();
+    #[allow(clippy::needless_range_loop)]
+    for i in 0..n_steps {
+        let start = get_time();
+        nova.prove_step(rng, pks_sigs[i], None).unwrap();
+        dbg(format!(
+            "Nova::prove_step {}: {:?}ms",
+            nova.i,
+            elapsed(start)
+        ));
+    }
+    dbg(format!(
+        "Nova's all {} steps time: {:?}ms",
+        n_steps,
+        elapsed(start_full)
+    ));
+
+    let ivc_proof = nova.ivc_proof();
+    let mut ivc_proof_bytes = vec![];
+    ivc_proof
+        .serialize_compressed(&mut ivc_proof_bytes)
+        .unwrap();
+
+    b64.encode(ivc_proof_bytes)
+}
+
+#[wasm_bindgen]
+pub fn verify_proof(verifier_params: String, ivc_proof: String) -> String {
+    let poseidon_config = poseidon_canonical_config::<Fr>();
+
+    let vp = FS::vp_deserialize_with_mode(
+        &mut b64.decode(verifier_params.clone()).unwrap().as_slice(),
+        ark_serialize::Compress::Yes,
+        ark_serialize::Validate::Yes,
+        poseidon_config.clone(), // fcircuit_params
+    )
+    .unwrap();
+    // let proof =
+    //     FS::IVCProof::deserialize_compressed(b64.decode(ivc_proof).unwrap().as_slice()).unwrap();
+    let proof = <Nova<G1, G2, FC, Pedersen<G1>, Pedersen<G2>, false> as FoldingScheme<
+        G1,
+        G2,
+        FC,
+    >>::IVCProof::deserialize_compressed(b64.decode(ivc_proof).unwrap().as_slice())
+    .unwrap();
+
+    FS::verify(
+        vp, // Nova's verifier params
+        proof,
+    )
+    .unwrap();
+    "verified".to_string()
+}

@@ -33,10 +33,10 @@ }
     }
 }
 impl<C: CurveGroup> SigPk<C> {
-    pub fn to_bytes(&self) -> Vec<u8> {
+    pub fn to_bytes(self) -> Vec<u8> {
         let sig_bytes = self.sig.to_bytes();
         let pk_bytes = self.pk.to_bytes();
-        vec![sig_bytes, pk_bytes].concat()
+        [sig_bytes, pk_bytes].concat()
     }
     pub fn from_bytes(b: Vec<u8>) -> Self {
         let u_point_size = C::Affine::generator().serialized_size(ark_serialize::Compress::No);
@@ -138,20 +138,13 @@ let sk = SigningKey::<C>::generate::<blake2::Blake2b512>(rng).unwrap();
     let pk = sk.public_key();
 
     // if prev_pk!=None, use it, else, set the new pk to it
-    let prev_pk = if prev_pk.is_some() {
-        prev_pk.unwrap()
-    } else {
-        *pk
-    };
+    let prev_pk = if let Some(v) = prev_pk { v } else { *pk };
 
     let msg = hash_pk(poseidon_config, prev_pk);
 
     let sig = sk
-        .sign::<blake2::Blake2b512>(&poseidon_config, &msg)
+        .sign::<blake2::Blake2b512>(poseidon_config, &msg)
         .unwrap();
-    pk.verify(&poseidon_config, &msg, &sig).unwrap();
-    SigPk {
-        pk: pk.clone(),
-        sig,
-    }
+    pk.verify(poseidon_config, &msg, &sig).unwrap();
+    SigPk { pk: *pk, sig }
 }

@@ -0,0 +1,57 @@
+#[cfg(target_arch = "wasm32")]
+use web_sys::console;
+
+pub fn set_panic_hook() {
+    // When the `console_error_panic_hook` feature is enabled, we can call the
+    // `set_panic_hook` function at least once during initialization, and then
+    // we will get better error messages if our code ever panics.
+    //
+    // For more details see
+    // https://github.com/rustwasm/console_error_panic_hook#readme
+    #[cfg(feature = "console_error_panic_hook")]
+    console_error_panic_hook::set_once();
+}
+
+pub fn dbg(s: String) {
+    #[cfg(target_arch = "wasm32")]
+    console::log_1(&s.into());
+
+    #[cfg(not(target_arch = "wasm32"))]
+    println!("{}", s);
+}
+
+pub fn get_time() -> u64 {
+    #[cfg(target_arch = "wasm32")]
+    let start = get_wasm_time() as u64;
+
+    #[cfg(not(target_arch = "wasm32"))]
+    let start = std::time::SystemTime::now()
+        .duration_since(std::time::UNIX_EPOCH)
+        .unwrap()
+        .as_millis() as u64;
+
+    start
+}
+
+pub fn elapsed(start: u64) -> u64 {
+    #[cfg(target_arch = "wasm32")]
+    let end = get_wasm_time() as u64;
+
+    #[cfg(not(target_arch = "wasm32"))]
+    let end = std::time::SystemTime::now()
+        .duration_since(std::time::UNIX_EPOCH)
+        .unwrap()
+        .as_millis() as u64;
+
+    end - start
+}
+
+#[cfg(target_arch = "wasm32")]
+fn get_wasm_time() -> u64 {
+    use web_sys::{window, Performance};
+    let window = window().expect("should have a window in this context");
+    let performance = window
+        .performance()
+        .expect("performance should be available");
+    performance.now() as u64
+}