From cb38360311d61e3ab6170102270b9f516a3f5054 Mon Sep 17 00:00:00 2001
From: Oskar Thoren <ot@oskarthoren.com>
Date: Fri, 18 Mar 2022 15:01:37 +0800
Subject: [PATCH] docs(rln): comments and notes

---
 rln/src/protocol.rs | 14 ++++++++++++++
 rln/src/public.rs   | 12 ++++++------
 2 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/rln/src/protocol.rs b/rln/src/protocol.rs
index ea3167a..a06dc8e 100644
--- a/rln/src/protocol.rs
+++ b/rln/src/protocol.rs
@@ -77,6 +77,11 @@ fn ark_to_bigint(n: Field) -> BigInt {
     n.to_bigint().expect("conversion always succeeds for uint")
 }
 
+// XXX This is different from zk-kit API:
+// const witness = RLN.genWitness(secretHash, merkleProof, epoch, signal, rlnIdentifier)
+// const fullProof = await RLN.genProof(witness, wasmFilePath, finalZkeyPath)
+//
+
 /// Generates a semaphore proof
 ///
 /// # Errors
@@ -90,6 +95,15 @@ pub fn generate_proof(
 ) -> Result<Proof<Bn<Parameters>>, ProofError> {
     let external_nullifier = hash_external_nullifier(external_nullifier);
     let signal = hash_signal(signal);
+    // TODO Fix inputs
+    // Semaphore genWitness corresponds to these
+    // RLN different, should be:
+    // identity_secret
+    // path_elements (merkleProof.siblings))
+    // identity_path_index (merkleProof.pathIndices)
+    // x (RLN.genSignalHash(signal), assuming shouldHash is true)
+    // epoch
+    // rln_identifier
     let inputs = [
         ("identityNullifier", vec![identity.nullifier]),
         ("identityTrapdoor", vec![identity.trapdoor]),
diff --git a/rln/src/public.rs b/rln/src/public.rs
index 238a99c..7551706 100644
--- a/rln/src/public.rs
+++ b/rln/src/public.rs
@@ -25,17 +25,17 @@ use num_bigint::BigInt;
 use serde::Deserialize;
 use serde_json;
 
-// XXX
-use bellman::pairing::ff::{Field, PrimeField, PrimeFieldRepr, ScalarEngine};
-use sapling_crypto::bellman::pairing::bn256::Bn256;
+// For RLN Rust version
+//use bellman::pairing::ff::{Field, PrimeField, PrimeFieldRepr, ScalarEngine};
+//use sapling_crypto::bellman::pairing::bn256::Bn256;
 
 // TODO Add Engine here? i.e. <E: Engine> not <Bn254>
-// NOTE Bn254 vs Bn256 mismatch! Tree is originally Bn256
-// TODO Figure out Bn254 vs Bn256 mismatch
+// TODO Assuming we want to use IncrementalMerkleTree, figure out type/trait conversions
+// TODO Adopt to new protocol structure
 pub struct RLN {
     circom: CircomCircuit<Bn254>,
     params: ProvingKey<Bn254>,
-    // TODO Replace Bn256 with Bn254 here
+    // RLN Rust version
     //tree: IncrementalMerkleTree<Bn256>,
     tree: PoseidonTree,
 }