From 506468522460a60680c53605ac48059a3106f348 Mon Sep 17 00:00:00 2001
From: Nanak Nihal Khalsa <nanaknihal@gmail.com>
Date: Wed, 27 Dec 2023 14:58:33 -0500
Subject: [PATCH] wasm blake hash compatability (but circom compatability
 broken in wasm still)

---
 Cargo.toml | 17 ++++++++++++-----
 src/lib.rs | 29 +++++++++++++++++++++++------
 2 files changed, 35 insertions(+), 11 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index d4a594a..e6d1362 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -16,8 +16,6 @@ rand = "0.4.6"
 num = "0.4"
 num-bigint = {version = "0.4", features = ["rand", "serde"]}
 num-traits = "0.2.8"
-blake-hash = {version="0.4.0", optional=true}
-blake = {version="2.0.1", optional=true}
 generic-array = "0.14"
 poseidon-rs = "0.0.8"
 arrayref = "0.3.5"
@@ -34,6 +32,15 @@ hex = "0.4"
 name = "bench_babyjubjub"
 harness = false
 
-[features]
-default = ["blake-hash"]
-aarch64 = ["blake"]
+[target.'cfg(not(any( target_arch = "aarch64", target_arch = "wasm32" )))'.dependencies]
+blake-hash = {version="0.4.1" }
+
+[target.'cfg(target_arch = "aarch64")'.dependencies]
+blake = { version = "2.0.1" }
+
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+blake2 = { version = "0.10.6" }
+
+# [features]
+# default = ["blake-hash"]
+# aarch64 = ["blake"]
diff --git a/src/lib.rs b/src/lib.rs
index bcd705a..7c7f113 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -21,12 +21,17 @@ pub struct Fl(FpRepr);
 
 use arrayref::array_ref;
 
-#[cfg(not(feature = "aarch64"))]
+#[cfg(not(any( target_arch = "aarch64", target_arch = "wasm32" )))]
 use blake_hash::Digest; // compatible version with Blake used at circomlib
 
-#[cfg(feature = "aarch64")]
+#[cfg( target_arch = "aarch64" )]
 extern crate blake; // compatible version with Blake used at circomlib
 
+
+#[cfg( target_arch = "wasm32" )]
+use blake2::{Blake2b512, Blake2s256, Digest}; // NOT compatible with circomlib but it works on WASM
+
+
 use std::{cmp::min, str::FromStr};
 
 use num_bigint::{BigInt, RandBigInt, Sign, ToBigInt};
@@ -465,19 +470,29 @@ pub fn decompress_point(bb: [u8; 32]) -> Result<Point, String> {
     Ok(Point { x: x_fr, y: y_fr })
 }
 
-#[cfg(not(feature = "aarch64"))]
-fn blh(b: &[u8]) -> Vec<u8> {
+#[cfg(not(any( target_arch = "aarch64", target_arch = "wasm32" )))]
+pub fn blh(b: &[u8]) -> Vec<u8> {
     let hash = blake_hash::Blake512::digest(b);
     hash.to_vec()
 }
 
-#[cfg(feature = "aarch64")]
-fn blh(b: &[u8]) -> Vec<u8> {
+#[cfg(target_arch = "aarch64")]
+pub fn blh(b: &[u8]) -> Vec<u8> {
     let mut hash = [0; 64];
     blake::hash(512, b, &mut hash).unwrap();
     hash.to_vec()
 }
 
+#[cfg(target_arch = "wasm32")]
+/// This is incompatible with the circom version
+/// TODO: find a BLAKE-512 that works on WASM
+pub fn blh(b: &[u8]) -> Vec<u8> {
+   let mut hasher = Blake2b512::new(); 
+   hasher.update(b); 
+   hasher.finalize().to_vec()
+}
+// #[cfg(target_arch = "wasm32")]
+
 #[derive(Debug, Clone, Serialize)]
 pub struct Signature {
     pub r_b8: Point,
@@ -549,6 +564,8 @@ impl PrivateKey {
     }
 
     pub fn public(&self) -> Point {
+        println!("calling public");
+        println!("scalar key {}", &self.scalar_key());
         B8.mul_scalar(&self.scalar_key())
     }