From 3427729f7eeff86b79b5e7f03a4985a1478d4d4b Mon Sep 17 00:00:00 2001
From: G <28568419+s1fr0@users.noreply.github.com>
Date: Wed, 23 Nov 2022 10:55:12 +0100
Subject: [PATCH] fix(semaphore): temporarily use fixed semaphore-rs fork (#79)

* fix(semaphore): temporarily use fixed semaphore-rs fork

* fix(semaphore): update semaphore logic to work with latest master of semaphore-rs
---
 semaphore/Cargo.toml      |  7 +++++--
 semaphore/src/protocol.rs | 19 ++++++++++---------
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/semaphore/Cargo.toml b/semaphore/Cargo.toml
index b6d0132..9efbaa7 100644
--- a/semaphore/Cargo.toml
+++ b/semaphore/Cargo.toml
@@ -19,9 +19,12 @@ ark-std = { version = "0.3.0", default-features = false, features = ["parallel"]
 color-eyre = "0.5"
 num-bigint = { version = "0.4", default-features = false, features = ["rand"] }
 once_cell = "1.8"
-primitive-types = "0.11.1"
 rand = "0.8.4"
-semaphore = { git = "https://github.com/worldcoin/semaphore-rs", rev = "d462a43"}
+# TODO: change back to original repo once https://github.com/worldcoin/semaphore-rs/pull/24 is merged
+#semaphore = { git = "https://github.com/worldcoin/semaphore-rs", rev = "d462a43"}
+semaphore = { git = "https://github.com/vacp2p/semaphore-rs", branch="fix-u256-data-type"}
+ethers-core = { git = "https://github.com/gakonst/ethers-rs", default-features = false }
+ruint = { version = "1.2.0", features = [ "serde", "num-bigint", "ark-ff" ] }
 serde = "1.0"
 thiserror = "1.0.0"
 wasmer = { version = "2.0" }
diff --git a/semaphore/src/protocol.rs b/semaphore/src/protocol.rs
index 7b82b60..f863370 100644
--- a/semaphore/src/protocol.rs
+++ b/semaphore/src/protocol.rs
@@ -13,12 +13,12 @@ use ark_groth16::{
 use ark_relations::r1cs::SynthesisError;
 use ark_std::UniformRand;
 use color_eyre::Result;
-use primitive_types::U256;
+use ethers_core::types::U256;
 use rand::{thread_rng, Rng};
 use semaphore::{
     identity::Identity,
     merkle_tree::{self, Branch},
-    poseidon_hash,
+    poseidon,
     poseidon_tree::PoseidonHash,
     Field,
 };
@@ -81,7 +81,7 @@ fn merkle_proof_to_vec(proof: &merkle_tree::Proof<PoseidonHash>) -> Vec<Field> {
 /// Generates the nullifier hash
 #[must_use]
 pub fn generate_nullifier_hash(identity: &Identity, external_nullifier: Field) -> Field {
-    poseidon_hash(&[external_nullifier, identity.nullifier])
+    poseidon::hash2(external_nullifier, identity.nullifier)
 }
 
 #[derive(Error, Debug)]
@@ -92,6 +92,8 @@ pub enum ProofError {
     WitnessError(color_eyre::Report),
     #[error("Error producing proof: {0}")]
     SynthesisError(#[from] SynthesisError),
+    #[error("Error converting public input: {0}")]
+    ToFieldError(#[from] ruint::ToFieldError),
 }
 
 /// Generates a semaphore proof
@@ -202,12 +204,11 @@ pub fn verify_proof(
     let zkey = zkey();
     let pvk = prepare_verifying_key(&zkey.0.vk);
 
-    let public_inputs = [
-        root.into(),
-        nullifier_hash.into(),
-        signal_hash.into(),
-        external_nullifier_hash.into(),
-    ];
+    let public_inputs = [root, nullifier_hash, signal_hash, external_nullifier_hash]
+        .iter()
+        .map(ark_bn254::Fr::try_from)
+        .collect::<Result<Vec<_>, _>>()?;
+
     let ark_proof = (*proof).into();
     let result = ark_groth16::verify_proof(&pvk, &ark_proof, &public_inputs[..])?;
     Ok(result)