prove with real params and small refactors

.gitignore

@@ -1 +1,2 @@
 /target
+.DS_STORE

Cargo.lock

@@ -79,7 +79,7 @@ dependencies = [
 [[package]]
 name = "ark-circom"
 version = "0.1.0"
-source = "git+https://github.com/gakonst/ark-circom#1a383b6260fd7b68aaade55af3a9edbd70e7f5f5"
+source = "git+https://github.com/philsippl/ark-circom#894aac9a20e5bb8fa26bf9cc7639134147ec1454"
 dependencies = [
  "ark-bn254",
  "ark-ec",

Cargo.toml

@@ -6,7 +6,7 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-ark-circom = { git = "https://github.com/gakonst/ark-circom", features=["circom-2"] }
+ark-circom = { git = "https://github.com/philsippl/ark-circom", features=["circom-2"] }
 ark-std = { version = "0.3.0", default-features = false, features = ["parallel"] }
 ark-bn254 = { version = "0.3.0" }
 ark-groth16 = { git = "https://github.com/arkworks-rs/groth16", rev = "765817f", features = ["parallel"] }

src/identity.rs

@@ -1,12 +1,9 @@
-use color_eyre::Result;
 use ff::{PrimeField, PrimeFieldRepr};
 use num_bigint::{BigInt, Sign};
 use once_cell::sync::Lazy;
 use poseidon_rs::{Fr, FrRepr, Poseidon};
 use sha2::{Digest, Sha256};
 
-use crate::{hash::Hash};
-
 static POSEIDON: Lazy<Poseidon> = Lazy::new(Poseidon::new);
 
 fn bigint_to_fr(bi: &BigInt) -> Fr {
@@ -32,8 +29,8 @@ fn fr_to_bigint(fr: Fr) -> BigInt {
 
 #[derive(Clone, PartialEq, Eq, Debug)]
 pub struct Identity {
-    pub identity_trapdoor: BigInt,
-    pub identity_nullifier: BigInt,
+    pub trapdoor: BigInt,
+    pub nullifier: BigInt,
 }
 
 // todo: improve
@@ -50,26 +47,26 @@ impl Identity {
         let seed_hash = &sha(seed);
 
         // https://github.com/appliedzkp/zk-kit/blob/1ea410456fc2b95877efa7c671bc390ffbfb5d36/packages/identity/src/identity.ts#L58
-        let identity_trapdoor = BigInt::from_bytes_be(
+        let trapdoor = BigInt::from_bytes_be(
             Sign::Plus,
             &sha(format!("{}identity_trapdoor", hex::encode(seed_hash)).as_bytes()),
         );
-        let identity_nullifier = BigInt::from_bytes_be(
+        let nullifier = BigInt::from_bytes_be(
             Sign::Plus,
             &sha(format!("{}identity_nullifier", hex::encode(seed_hash)).as_bytes()),
         );
 
         Self {
-            identity_trapdoor,
-            identity_nullifier,
+            trapdoor,
+            nullifier,
         }
     }
 
     pub fn secret_hash(&self) -> BigInt {
         let res = POSEIDON
             .hash(vec![
-                bigint_to_fr(&self.identity_nullifier),
-                bigint_to_fr(&self.identity_trapdoor),
+                bigint_to_fr(&self.nullifier),
+                bigint_to_fr(&self.trapdoor),
             ])
             .unwrap();
         fr_to_bigint(res)
@@ -82,11 +79,4 @@ impl Identity {
         fr_to_bigint(res)
     }
 
-    pub fn identity_commitment_leaf(&self) -> Hash {
-        let res = POSEIDON
-            .hash(vec![bigint_to_fr(&self.identity_commitment())])
-            .unwrap();
-
-        res.into()
-    }
 }

src/main.rs

@@ -26,12 +26,15 @@ fn main() {
     let (_, leaf) = id.identity_commitment().to_bytes_be();
     dbg!(&leaf);
 
-    tree.set(0, leaf.into());
+    tree.set(2, leaf.into());
 
     let root: BigInt = tree.root().into();
     dbg!(root);
 
-    let proof = tree.proof(0).expect("proof should exist");
+    let proof = tree.proof(2).expect("proof should exist");
+
+    dbg!(proof.path_index());
+
     // let proof: Vec<BigInt> = proof.0.iter().map(|x| {
     //     match x {
     //         Branch::Left(value) => value.into(),

src/merkle_tree.rs

@@ -173,6 +173,15 @@ impl<H: Hasher> Proof<H> {
         })
     }
 
+    /// Compute path index (TODO: do we want to keep this here?)
+    #[allow(dead_code)]
+    pub fn path_index(&self) -> Vec<BigInt> {
+        self.0.iter().map(|branch| match branch {
+            Branch::Left(_) => BigInt::from(0),
+            Branch::Right(_) => BigInt::from(1),
+        }).collect()
+    }
+
     /// Compute the Merkle root given a leaf hash
     #[allow(dead_code)]
     pub fn root(&self, hash: H::Hash) -> H::Hash {

src/proof.rs

@@ -1,4 +1,4 @@
-use ark_circom::{CircomConfig, CircomBuilder, read_zkey, WitnessCalculator, CircomReduction};
+use ark_circom::{read_zkey, WitnessCalculator, CircomReduction};
 use ark_std::rand::thread_rng;
 use ark_bn254::Bn254;
 use color_eyre::Result;
@@ -9,19 +9,21 @@ use std::{collections::HashMap, fs::File};
 use crate::{identity::*, poseidon_tree::{Proof}, merkle_tree::Branch};
 
 use ark_groth16::{
-    create_random_proof as prove, generate_random_parameters, prepare_verifying_key, verify_proof, create_proof_with_reduction_and_matrices,
+    prepare_verifying_key, verify_proof, create_proof_with_reduction_and_matrices,
 };
 
-// WIP: uses dummy proofs for now
-pub fn proof_signal(identity: &Identity, proof: &Proof) -> Result<()> {
-
-    // TODO: we should create a From trait for this
-    let proof = proof.0.iter().map(|x| {
+// TODO: we should create a From trait for this
+fn proof_to_vec(proof: &Proof) -> Vec<BigInt> {
+    proof.0.iter().map(|x| {
         match x {
             Branch::Left(value) => value.into(),
             Branch::Right(value) => value.into(),
         }
-    }).collect::<Vec<BigInt>>();
+    }).collect::<Vec<BigInt>>()
+}
+
+// WIP: uses dummy proofs for now
+pub fn proof_signal(identity: &Identity, merkle_proof: &Proof, external_nullifier: BigInt) -> Result<()> {
 
     let mut file = File::open("./snarkfiles/semaphore.zkey").unwrap();
     let (params, matrices) = read_zkey(&mut file).unwrap();
@@ -29,40 +31,13 @@ pub fn proof_signal(identity: &Identity, proof: &Proof) -> Result<()> {
     let num_constraints = matrices.num_constraints;
 
     let inputs = {
-        let mut inputs: HashMap<String, Vec<num_bigint::BigInt>> = HashMap::new();
+        let mut inputs: HashMap<String, Vec<BigInt>> = HashMap::new();
 
-        let values = inputs.entry("identity_nullifier".to_string()).or_insert_with(Vec::new);
-        values.push(BigInt::parse_bytes(
-            b"4344141139294650952352150677542411196253771789435022697920397562624821372579",
-            10,
-        )
-        .unwrap());
-
-        //
-
-        let values = inputs.entry("identity_trapdoor".to_string()).or_insert_with(Vec::new);
-        values.push(BigInt::parse_bytes(
-            b"57215223214535428002775309386374815284773502419290683020798284477163412139477",
-            10,
-        )
-        .unwrap());
-
-        //
-
-        let values = inputs.entry("identity_path_index".to_string()).or_insert_with(Vec::new);
-        values.push(BigInt::from(0 as i32));
-        values.push(BigInt::from(0 as i32));
-
-        //
-        let values = inputs.entry("path_elements".to_string()).or_insert_with(Vec::new);
-        for el in proof {
-            values.push(el);
-        }
-
-        //
-
-        let values = inputs.entry("external_nullifier".to_string()).or_insert_with(Vec::new);
-        values.push(BigInt::from(123 as i32));
+        inputs.insert("identity_nullifier".to_string(), vec![identity.nullifier.clone()]);
+        inputs.insert("identity_trapdoor".to_string(), vec![identity.trapdoor.clone()]);
+        inputs.insert("identity_path_index".to_string(), merkle_proof.path_index());
+        inputs.insert("path_elements".to_string(), proof_to_vec(merkle_proof));
+        inputs.insert("external_nullifier".to_string(), vec![external_nullifier]);
 
         //