chore: Release

* Expose generate proof with witness ffi

* Force run CI

* Update ci.yml

* Fix wasm with_witness

* Remove forced CI run

.github/workflows/ci.yml

@@ -3,32 +3,39 @@ on:
     branches:
       - master
     paths-ignore:
-      - "**.md"
-      - "!.github/workflows/*.yml"
-      - "!rln-wasm/**"
-      - "!rln/src/**"
-      - "!rln/resources/**"
-      - "!utils/src/**"
+      - '**.md'
+      - '!.github/workflows/*.yml'
+      - '!multiplier/src/**'
+      - '!private-settlement/src/**'
+      - '!rln-wasm/**'
+      - '!rln/src/**'
+      - '!rln/resources/**'
+      - '!semaphore/src/**'
+      - '!utils/src/**'
   pull_request:
     paths-ignore:
-      - "**.md"
-      - "!.github/workflows/*.yml"
-      - "!rln-wasm/**"
-      - "!rln/src/**"
-      - "!rln/resources/**"
-      - "!utils/src/**"
+      - '**.md'
+      - '!.github/workflows/*.yml'
+      - '!multiplier/src/**'
+      - '!private-settlement/src/**'
+      - '!rln-wasm/**'
+      - '!rln/src/**'
+      - '!rln/resources/**'
+      - '!semaphore/src/**'
+      - '!utils/src/**'
+
 
 name: Tests
 
 jobs:
-  utils-test:
+  test:
     strategy:
       matrix:
-        platform: [ ubuntu-latest, macos-latest ]
-        crate: [ utils ]
+        platform: [ubuntu-latest, macos-latest]
+        crate: [multiplier, semaphore, rln, utils]
     runs-on: ${{ matrix.platform }}
     timeout-minutes: 60
-
+  
     name: test - ${{ matrix.crate }} - ${{ matrix.platform }}
     steps:
       - name: Checkout sources
@@ -44,43 +51,16 @@ jobs:
         run: make installdeps
       - name: cargo-make test
         run: |
-          cargo make test --release
+            cargo make test --release
         working-directory: ${{ matrix.crate }}
-
-  rln-test:
-    strategy:
-      matrix:
-        platform: [ ubuntu-latest, macos-latest ]
-        crate: [ rln ]
-        feature: [ "default", "arkzkey", "stateless" ]
-    runs-on: ${{ matrix.platform }}
-    timeout-minutes: 60
-
-    name: test - ${{ matrix.crate }} - ${{ matrix.platform }} - ${{ matrix.feature }}
-    steps:
-      - name: Checkout sources
-        uses: actions/checkout@v3
-      - name: Install stable toolchain
-        uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: stable
-          override: true
-      - uses: Swatinem/rust-cache@v2
-      - name: Install dependencies
-        run: make installdeps
-      - name: cargo-make test
-        run: |
-          cargo make test_${{ matrix.feature }} --release
-        working-directory: ${{ matrix.crate }}
-
+  
   rln-wasm:
     strategy:
       matrix:
-        platform: [ ubuntu-latest, macos-latest ]
+        platform: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.platform }}
     timeout-minutes: 60
-
+  
     name: test - rln-wasm - ${{ matrix.platform }}
     steps:
       - uses: actions/checkout@v3
@@ -88,8 +68,7 @@ jobs:
         uses: actions-rs/toolchain@v1
         with:
           profile: minimal
-          # TODO: Update to stable once wasmer supports it
-          toolchain: 1.82.0
+          toolchain: stable
           override: true
       - uses: Swatinem/rust-cache@v2
       - name: Install Dependencies
@@ -105,12 +84,12 @@ jobs:
     strategy:
       matrix:
         # we run lint tests only on ubuntu
-        platform: [ ubuntu-latest ]
-        crate: [ rln, utils ]
+        platform: [ubuntu-latest]
+        crate: [multiplier, semaphore, rln, utils]
     runs-on: ${{ matrix.platform }}
     timeout-minutes: 60
 
-    name: lint - ${{ matrix.crate }} - ${{ matrix.platform }}
+    name: lint - ${{ matrix.crate }} - ${{ matrix.platform }}  
     steps:
       - name: Checkout sources
         uses: actions/checkout@v3
@@ -131,20 +110,19 @@ jobs:
       - name: cargo clippy
         if: success() || failure()
         run: |
-          cargo clippy --release -- -D warnings
+            cargo clippy --release -- -D warnings
         working-directory: ${{ matrix.crate }}
         # We skip clippy on rln-wasm, since wasm target is managed by cargo make
         # Currently not treating warnings as error, too noisy
         # -- -D warnings
-
-  benchmark-utils:
+  benchmark:
     # run only in pull requests
     if: github.event_name == 'pull_request'
     strategy:
       matrix:
         # we run benchmark tests only on ubuntu
-        platform: [ ubuntu-latest ]
-        crate: [ utils ]
+        platform: [ubuntu-latest]
+        crate: [rln, utils]
     runs-on: ${{ matrix.platform }}
     timeout-minutes: 60
 
@@ -157,26 +135,3 @@ jobs:
         with:
           branchName: ${{ github.base_ref }}
           cwd: ${{ matrix.crate }}
-
-  benchmark-rln:
-    # run only in pull requests
-    if: github.event_name == 'pull_request'
-    strategy:
-      matrix:
-        # we run benchmark tests only on ubuntu
-        platform: [ ubuntu-latest ]
-        crate: [ rln ]
-        feature: [ "default", "arkzkey" ]
-    runs-on: ${{ matrix.platform }}
-    timeout-minutes: 60
-
-    name: benchmark - ${{ matrix.platform }} - ${{ matrix.crate }} - ${{ matrix.feature }}
-    steps:
-      - name: Checkout sources
-        uses: actions/checkout@v3
-      - uses: Swatinem/rust-cache@v2
-      - uses: boa-dev/criterion-compare-action@v3
-        with:
-          branchName: ${{ github.base_ref }}
-          cwd: ${{ matrix.crate }}
-          features: ${{ matrix.feature }}

.github/workflows/nightly-release.yml

@@ -8,14 +8,10 @@ jobs:
   linux:
     strategy:
       matrix:
-        feature: [ "default", "arkzkey", "stateless" ]
-        target:
+        target: 
           - x86_64-unknown-linux-gnu
           - aarch64-unknown-linux-gnu
           - i686-unknown-linux-gnu
-        include:
-          - feature: stateless
-            cargo_args: --exclude rln-cli
     name: Linux build
     runs-on: ubuntu-latest
     steps:
@@ -33,16 +29,16 @@ jobs:
         run: make installdeps
       - name: cross build
         run: |
-          cross build --release --target ${{ matrix.target }} --features ${{ matrix.feature }} --workspace --exclude rln-wasm ${{ matrix.cargo_args }}
+          cross build --release --target ${{ matrix.target }} --workspace --exclude rln-wasm
           mkdir release
           cp target/${{ matrix.target }}/release/librln* release/
-          tar -czvf ${{ matrix.target }}-${{ matrix.feature }}-rln.tar.gz release/
+          tar -czvf ${{ matrix.target }}-rln.tar.gz release/
 
       - name: Upload archive artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v2
         with:
-          name: ${{ matrix.target }}-${{ matrix.feature }}-archive
-          path: ${{ matrix.target }}-${{ matrix.feature }}-rln.tar.gz
+          name: ${{ matrix.target }}-archive
+          path: ${{ matrix.target }}-rln.tar.gz
           retention-days: 2
 
   macos:
@@ -50,13 +46,9 @@ jobs:
     runs-on: macos-latest
     strategy:
       matrix:
-        feature: [ "default", "arkzkey", "stateless" ]
-        target:
+        target: 
           - x86_64-apple-darwin
           - aarch64-apple-darwin
-        include:
-          - feature: stateless
-            cargo_args: --exclude rln-cli
     steps:
       - name: Checkout sources
         uses: actions/checkout@v3
@@ -72,18 +64,18 @@ jobs:
         run: make installdeps
       - name: cross build
         run: |
-          cross build --release --target ${{ matrix.target }} --features ${{ matrix.feature }} --workspace --exclude rln-wasm ${{ matrix.cargo_args }}
+          cross build --release --target ${{ matrix.target }} --workspace --exclude rln-wasm
           mkdir release
           cp target/${{ matrix.target }}/release/librln* release/
-          tar -czvf ${{ matrix.target }}-${{ matrix.feature }}-rln.tar.gz release/
+          tar -czvf ${{ matrix.target }}-rln.tar.gz release/
 
       - name: Upload archive artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v2
         with:
-          name: ${{ matrix.target }}-${{ matrix.feature }}-archive
-          path: ${{ matrix.target }}-${{ matrix.feature }}-rln.tar.gz
+          name: ${{ matrix.target }}-archive
+          path: ${{ matrix.target }}-rln.tar.gz
           retention-days: 2
-
+  
   browser-rln-wasm:
     name: Browser build (RLN WASM)
     runs-on: ubuntu-latest
@@ -94,8 +86,7 @@ jobs:
         uses: actions-rs/toolchain@v1
         with:
           profile: minimal
-          # TODO: Update to stable once wasmer supports it
-          toolchain: 1.82.0
+          toolchain: stable
           override: true
       - uses: Swatinem/rust-cache@v2
       - name: Install dependencies
@@ -111,15 +102,16 @@ jobs:
         working-directory: rln-wasm
 
       - name: Upload archive artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v2
         with:
           name: browser-rln-wasm-archive
           path: rln-wasm/browser-rln-wasm.tar.gz
           retention-days: 2
 
+
   prepare-prerelease:
     name: Prepare pre-release
-    needs: [ linux, macos, browser-rln-wasm ]
+    needs: [linux, macos, browser-rln-wasm]
     runs-on: ubuntu-latest
     steps:
       - name: Checkout code
@@ -127,8 +119,8 @@ jobs:
         with:
           ref: master
       - name: Download artifacts
-        uses: actions/download-artifact@v4
-
+        uses: actions/download-artifact@v2
+          
       - name: Delete tag
         uses: dev-drprasad/delete-tag-and-release@v0.2.1
         with:
@@ -150,7 +142,7 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Delete artifacts
-        uses: geekyeggo/delete-artifact@v5
+        uses: geekyeggo/delete-artifact@v1
         with:
           failOnError: false
           name: |

.gitmodules

@@ -0,0 +1,8 @@
+[submodule "rln/vendor/rln"]
+	path = rln/vendor/rln
+	ignore = dirty
+	url = https://github.com/Rate-Limiting-Nullifier/rln_circuits.git
+[submodule "semaphore/vendor/semaphore"]
+	path = semaphore/vendor/semaphore
+	ignore = dirty
+	url = https://github.com/appliedzkp/semaphore.git

Cargo.toml

@@ -1,6 +1,13 @@
 [workspace]
-members = ["rln", "rln-cli", "rln-wasm", "utils"]
-default-members = ["rln", "rln-cli", "utils"]
+members = [
+  "multiplier",
+  "private-settlement",
+  "semaphore",
+  "rln",
+  "rln-cli",
+  "rln-wasm",
+  "utils",
+]
 resolver = "2"
 
 # Compilation profile for any non-workspace member.
@@ -12,3 +19,6 @@ opt-level = 3
 [profile.release.package."rln-wasm"]
 # Tell `rustc` to optimize for small code size.
 opt-level = "s"
+
+[profile.release.package."semaphore"]
+codegen-units = 1

Makefile

@@ -13,19 +13,15 @@ endif
 
 installdeps: .pre-build
 ifeq ($(shell uname),Darwin)
-# commented due to https://github.com/orgs/Homebrew/discussions/4612
-# @brew update
+# commented due to https://github.com/orgs/Homebrew/discussions/4612	
+# @brew update 
 	@brew install cmake ninja
 else ifeq ($(shell uname),Linux)
 	@sudo apt-get update
 	@sudo apt-get install -y cmake ninja-build
 endif
-	@git -C "wabt" pull || git clone --recursive https://github.com/WebAssembly/wabt.git "wabt"
-	@cd wabt && mkdir -p build && cd build && cmake .. -GNinja && ninja && sudo ninja install
-	@which wasm-pack || cargo install wasm-pack
-	# nvm already checks if it's installed, and no-ops if it is
-	@curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.7/install.sh | bash
-	@. ${HOME}/.nvm/nvm.sh && nvm install 18.20.2 && nvm use 18.20.2;
+	@git clone --recursive https://github.com/WebAssembly/wabt.git
+	@cd wabt && mkdir build && cd build && cmake .. -GNinja && ninja && sudo ninja install
 
 build: .pre-build
 	@cargo make build

README.md

@@ -18,23 +18,13 @@ in Rust.
 
 - [semaphore-rs](https://github.com/worldcoin/semaphore-rs) written in Rust based on ark-circom.
 
-## Users
-
-Zerokit is used by -
-
-- [nwaku](https://github.com/waku-org/nwaku)
-- [js-rln](https://github.com/waku-org/js-rln)
-
 ## Build and Test
 
 To install missing dependencies, run the following commands from the root folder
-
 ```bash
 make installdeps
 ```
-
 To build and test all crates, run the following commands from the root folder
-
 ```bash
 make build
 make test
@@ -42,4 +32,4 @@ make test
 
 ## Release assets
 
-We use [`cross-rs`](https://github.com/cross-rs/cross) to cross-compile and generate release assets for rln.
+We use [`cross-rs`](https://github.com/cross-rs/cross) to cross-compile and generate release assets for rln. 

multiplier/Cargo.toml

@@ -0,0 +1,32 @@
+[package]
+name = "multiplier"
+version = "0.3.0"
+edition = "2018"
+license = "MIT OR Apache-2.0"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+
+# WASM operations
+# wasmer = { version = "2.0" }
+# fnv = { version = "1.0.3", default-features = false }
+# num = { version = "0.4.0" }
+# num-traits = { version = "0.2.0", default-features = false }
+
+# ZKP Generation
+# ark-ff = { version = "0.3.0", default-features = false, features = ["parallel", "asm"] }
+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"] }
+# ark-poly = { version = "^0.3.0", default-features = false, features = ["parallel"] }
+ark-serialize = { version = "0.3.0", default-features = false }
+
+ark-circom = { git = "https://github.com/gakonst/ark-circom", features = ["circom-2"], rev = "35ce5a9" }
+
+# error handling
+color-eyre = "0.6.1"
+
+# decoding of data
+# hex = "0.4.3"
+# byteorder = "1.4.3"

multiplier/Makefile.toml

@@ -0,0 +1,7 @@
+[tasks.build]
+command = "cargo"
+args = ["build", "--release"]
+
+[tasks.test]
+command = "cargo"
+args = ["test", "--release"]

multiplier/README.md

@@ -0,0 +1,21 @@
+# Multiplier example
+
+Example wrapper around a basic Circom circuit to test Circom 2 integration
+through ark-circom and FFI.
+
+## Build and Test
+
+To build and test, run the following commands within the module folder
+```bash
+cargo make build
+cargo make test
+```
+
+## FFI
+
+To generate C or Nim bindings from Rust FFI, use `cbindgen` or `nbindgen`:
+
+```
+cbindgen . -o target/multiplier.h
+nbindgen . -o target/multiplier.nim
+```

multiplier/src/ffi.rs

@@ -0,0 +1,77 @@
+use crate::public::Multiplier;
+use std::slice;
+
+/// Buffer struct is taken from
+/// https://github.com/celo-org/celo-threshold-bls-rs/blob/master/crates/threshold-bls-ffi/src/ffi.rs
+///
+/// Also heavily inspired by https://github.com/kilic/rln/blob/master/src/ffi.rs
+
+#[repr(C)]
+#[derive(Clone, Debug, PartialEq)]
+pub struct Buffer {
+    pub ptr: *const u8,
+    pub len: usize,
+}
+
+impl From<&[u8]> for Buffer {
+    fn from(src: &[u8]) -> Self {
+        Self {
+            ptr: &src[0] as *const u8,
+            len: src.len(),
+        }
+    }
+}
+
+impl<'a> From<&Buffer> for &'a [u8] {
+    fn from(src: &Buffer) -> &'a [u8] {
+        unsafe { slice::from_raw_parts(src.ptr, src.len) }
+    }
+}
+
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[no_mangle]
+pub extern "C" fn new_circuit(ctx: *mut *mut Multiplier) -> bool {
+    if let Ok(mul) = Multiplier::new() {
+        unsafe { *ctx = Box::into_raw(Box::new(mul)) };
+        true
+    } else {
+        false
+    }
+}
+
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[no_mangle]
+pub extern "C" fn prove(ctx: *const Multiplier, output_buffer: *mut Buffer) -> bool {
+    println!("multiplier ffi: prove");
+    let mul = unsafe { &*ctx };
+    let mut output_data: Vec<u8> = Vec::new();
+
+    match mul.prove(&mut output_data) {
+        Ok(proof_data) => proof_data,
+        Err(_) => return false,
+    };
+    unsafe { *output_buffer = Buffer::from(&output_data[..]) };
+    std::mem::forget(output_data);
+    true
+}
+
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[no_mangle]
+pub extern "C" fn verify(
+    ctx: *const Multiplier,
+    proof_buffer: *const Buffer,
+    result_ptr: *mut u32,
+) -> bool {
+    println!("multiplier ffi: verify");
+    let mul = unsafe { &*ctx };
+    let proof_data = <&[u8]>::from(unsafe { &*proof_buffer });
+    if match mul.verify(proof_data) {
+        Ok(verified) => verified,
+        Err(_) => return false,
+    } {
+        unsafe { *result_ptr = 0 };
+    } else {
+        unsafe { *result_ptr = 1 };
+    };
+    true
+}

multiplier/src/lib.rs

@@ -0,0 +1,2 @@
+pub mod ffi;
+pub mod public;

multiplier/src/main.rs

@@ -0,0 +1,49 @@
+use ark_circom::{CircomBuilder, CircomConfig};
+use ark_std::rand::thread_rng;
+use color_eyre::{Report, Result};
+
+use ark_bn254::Bn254;
+use ark_groth16::{
+    create_random_proof as prove, generate_random_parameters, prepare_verifying_key, verify_proof,
+};
+
+fn groth16_proof_example() -> Result<()> {
+    let cfg = CircomConfig::<Bn254>::new(
+        "./resources/circom2_multiplier2.wasm",
+        "./resources/circom2_multiplier2.r1cs",
+    )?;
+
+    let mut builder = CircomBuilder::new(cfg);
+    builder.push_input("a", 3);
+    builder.push_input("b", 11);
+
+    // create an empty instance for setting it up
+    let circom = builder.setup();
+
+    let mut rng = thread_rng();
+    let params = generate_random_parameters::<Bn254, _, _>(circom, &mut rng)?;
+
+    let circom = builder.build()?;
+
+    let inputs = circom
+        .get_public_inputs()
+        .ok_or(Report::msg("no public inputs"))?;
+
+    let proof = prove(circom, &params, &mut rng)?;
+
+    let pvk = prepare_verifying_key(&params.vk);
+
+    match verify_proof(&pvk, &proof, &inputs) {
+        Ok(_) => Ok(()),
+        Err(_) => Err(Report::msg("not verified")),
+    }
+}
+
+fn main() {
+    println!("Hello, world!");
+
+    match groth16_proof_example() {
+        Ok(_) => println!("Success"),
+        Err(_) => println!("Error"),
+    }
+}

multiplier/src/public.rs

@@ -0,0 +1,79 @@
+use ark_circom::{CircomBuilder, CircomCircuit, CircomConfig};
+use ark_std::rand::thread_rng;
+
+use ark_bn254::Bn254;
+use ark_groth16::{
+    create_random_proof as prove, generate_random_parameters, prepare_verifying_key, verify_proof,
+    Proof, ProvingKey,
+};
+use ark_serialize::{CanonicalDeserialize, CanonicalSerialize};
+use color_eyre::{Report, Result};
+use std::io::{Read, Write};
+
+pub struct Multiplier {
+    circom: CircomCircuit<Bn254>,
+    params: ProvingKey<Bn254>,
+}
+
+impl Multiplier {
+    // TODO Break this apart here
+    pub fn new() -> Result<Multiplier> {
+        let cfg = CircomConfig::<Bn254>::new(
+            "./resources/circom2_multiplier2.wasm",
+            "./resources/circom2_multiplier2.r1cs",
+        )?;
+
+        let mut builder = CircomBuilder::new(cfg);
+        builder.push_input("a", 3);
+        builder.push_input("b", 11);
+
+        // create an empty instance for setting it up
+        let circom = builder.setup();
+
+        let mut rng = thread_rng();
+
+        let params = generate_random_parameters::<Bn254, _, _>(circom, &mut rng)?;
+
+        let circom = builder.build()?;
+
+        Ok(Multiplier { circom, params })
+    }
+
+    // TODO Input Read
+    pub fn prove<W: Write>(&self, result_data: W) -> Result<()> {
+        let mut rng = thread_rng();
+
+        // XXX: There's probably a better way to do this
+        let circom = self.circom.clone();
+        let params = self.params.clone();
+
+        let proof = prove(circom, &params, &mut rng)?;
+
+        // XXX: Unclear if this is different from other serialization(s)
+        proof.serialize(result_data)?;
+
+        Ok(())
+    }
+
+    pub fn verify<R: Read>(&self, input_data: R) -> Result<bool> {
+        let proof = Proof::deserialize(input_data)?;
+
+        let pvk = prepare_verifying_key(&self.params.vk);
+
+        // XXX Part of input data?
+        let inputs = self
+            .circom
+            .get_public_inputs()
+            .ok_or(Report::msg("no public inputs"))?;
+
+        let verified = verify_proof(&pvk, &proof, &inputs)?;
+
+        Ok(verified)
+    }
+}
+
+impl Default for Multiplier {
+    fn default() -> Self {
+        Self::new().unwrap()
+    }
+}

multiplier/tests/public.rs

@@ -0,0 +1,21 @@
+#[cfg(test)]
+mod tests {
+    use multiplier::public::Multiplier;
+
+    #[test]
+    fn multiplier_proof() {
+        let mul = Multiplier::new().unwrap();
+
+        let mut output_data: Vec<u8> = Vec::new();
+        let _ = mul.prove(&mut output_data);
+
+        let proof_data = &output_data[..];
+
+        // XXX Pass as arg?
+        //let pvk = prepare_verifying_key(&mul.params.vk);
+
+        let verified = mul.verify(proof_data).unwrap();
+
+        assert!(verified);
+    }
+}

private-settlement/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "private-settlement"
+version = "0.3.0"
+edition = "2021"
+license = "MIT OR Apache-2.0"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

private-settlement/Makefile.toml

@@ -0,0 +1,7 @@
+[tasks.build]
+command = "cargo"
+args = ["build", "--release"]
+
+[tasks.test]
+command = "cargo"
+args = ["test", "--release"]

private-settlement/README.md

@@ -0,0 +1,11 @@
+# Private Settlement  Module
+
+This module is to provide APIs to manage, compute and verify [Private Settlement](https://rfc.vac.dev/spec/44/) zkSNARK proofs and primitives.
+
+## Build and Test
+
+To build and test, run the following commands within the module folder
+```bash
+cargo make build
+cargo make test
+```

private-settlement/src/lib.rs

@@ -0,0 +1 @@
+

private-settlement/tests/private-settlement.rs

@@ -0,0 +1,11 @@
+#[cfg(test)]
+mod tests {
+    #[cfg(test)]
+    mod tests {
+        #[test]
+        fn it_works() {
+            let result = 2 + 2;
+            assert_eq!(result, 4);
+        }
+    }
+}

rln-cli/Cargo.toml

@@ -4,7 +4,7 @@ version = "0.3.0"
 edition = "2021"
 
 [dependencies]
-rln = { path = "../rln", default-features = true, features = ["arkzkey"] }
+rln = { path = "../rln" }
 clap = { version = "4.2.7", features = ["cargo", "derive", "env"]}
 clap_derive = { version = "=4.2.0" }
 color-eyre = "=0.6.2"

rln-cli/src/main.rs

@@ -37,11 +37,7 @@ fn main() -> Result<()> {
             tree_config_input,
         }) => {
             let mut resources: Vec<Vec<u8>> = Vec::new();
-            #[cfg(feature = "arkzkey")]
-            let filenames = ["rln.wasm", "rln_final.arkzkey", "verification_key.arkvkey"];
-            #[cfg(not(feature = "arkzkey"))]
-            let filenames = ["rln.wasm", "rln_final.zkey", "verification_key.arkvkey"];
-            for filename in filenames {
+            for filename in ["rln.wasm", "rln_final.zkey", "verification_key.json"] {
                 let fullpath = config.join(Path::new(filename));
                 let mut file = File::open(&fullpath)?;
                 let metadata = std::fs::metadata(&fullpath)?;

rln-cli/src/state.rs

@@ -5,12 +5,12 @@ use std::fs::File;
 use crate::config::{Config, InnerConfig};
 
 #[derive(Default)]
-pub(crate) struct State {
-    pub rln: Option<RLN>,
+pub(crate) struct State<'a> {
+    pub rln: Option<RLN<'a>>,
 }
 
-impl State {
-    pub(crate) fn load_state() -> Result<State> {
+impl<'a> State<'a> {
+    pub(crate) fn load_state() -> Result<State<'a>> {
         let config = Config::load_config()?;
         let rln = if let Some(InnerConfig { file, tree_height }) = config.inner {
             let resources = File::open(&file)?;

rln-wasm/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rln-wasm"
-version = "0.1.0"
+version = "0.0.9"
 edition = "2021"
 license = "MIT or Apache2"
 
@@ -11,16 +11,10 @@ crate-type = ["cdylib", "rlib"]
 default = ["console_error_panic_hook"]
 
 [dependencies]
-rln = { path = "../rln", default-features = false, features = [
-    "wasm",
-    "stateless",
-], version = "=0.6.1"}
-num-bigint = { version = "0.4", default-features = false, features = [
-    "rand",
-    "serde",
-] }
+rln = { path = "../rln", default-features = false, features = ["wasm"] }
+num-bigint = { version = "0.4", default-features = false, features = ["rand", "serde"] }
 wasmer = { version = "2.3", default-features = false, features = ["js", "std"] }
-web-sys = { version = "0.3", features = ["console"] }
+web-sys = {version = "0.3", features=["console"]}
 getrandom = { version = "0.2.7", default-features = false, features = ["js"] }
 wasm-bindgen = "0.2.63"
 serde-wasm-bindgen = "0.4"
@@ -32,8 +26,8 @@ serde_json = "1.0.85"
 # all the `std::fmt` and `std::panicking` infrastructure, so isn't great for
 # code size when deploying.
 console_error_panic_hook = { version = "0.1.7", optional = true }
-zerokit_utils = { version = "0.5.1", path = "../utils" }
 
 [dev-dependencies]
 wasm-bindgen-test = "0.3.13"
 wasm-bindgen-futures = "0.4.33"
+

rln-wasm/Makefile.toml

@@ -7,7 +7,11 @@ script = "sed -i.bak 's/rln-wasm/zerokit-rln-wasm/g' pkg/package.json && rm pkg/
 
 [tasks.build]
 clear = true
-dependencies = ["pack-build", "pack-rename", "post-build"]
+dependencies = [
+    "pack-build",
+    "pack-rename",
+    "post-build"
+]
 
 [tasks.post-build]
 command = "wasm-strip"
@@ -25,7 +29,3 @@ args = ["login"]
 [tasks.publish]
 command = "wasm-pack"
 args = ["publish", "--access", "public", "--target", "web"]
-
-[tasks.bench]
-command = "echo"
-args = ["'No benchmarks available for this project'"]

rln-wasm/src/lib.rs

@@ -19,7 +19,7 @@ pub fn init_panic_hook() {
 pub struct RLNWrapper {
     // The purpose of this wrapper is to hold a RLN instance with the 'static lifetime
     // because wasm_bindgen does not allow returning elements with lifetimes
-    instance: RLN,
+    instance: RLN<'static>,
 }
 
 // Macro to call methods with arbitrary amount of arguments,
@@ -150,8 +150,8 @@ impl<T> ProcessArg for Vec<T> {
     }
 }
 
-impl ProcessArg for *const RLN {
-    type ReturnType = &'static RLN;
+impl<'a> ProcessArg for *const RLN<'a> {
+    type ReturnType = &'a RLN<'a>;
     fn process(self) -> Self::ReturnType {
         unsafe { &*self }
     }
@@ -182,27 +182,96 @@ impl<'a> ProcessArg for &'a [u8] {
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[wasm_bindgen(js_name = newRLN)]
 pub fn wasm_new(
+    tree_height: usize,
     zkey: Uint8Array,
     vk: Uint8Array,
 ) -> Result<*mut RLNWrapper, String> {
-    let instance = RLN::new_with_params(zkey.to_vec(), vk.to_vec())
+    let instance = RLN::new_with_params(tree_height, zkey.to_vec(), vk.to_vec())
         .map_err(|err| format!("{:#?}", err))?;
     let wrapper = RLNWrapper { instance };
     Ok(Box::into_raw(Box::new(wrapper)))
 }
 
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[wasm_bindgen(js_name = getSerializedRLNWitness)]
+pub fn wasm_get_serialized_rln_witness(
+    ctx: *mut RLNWrapper,
+    input: Uint8Array,
+) -> Result<Uint8Array, String> {
+    let rln_witness = call!(ctx, get_serialized_rln_witness, &input.to_vec()[..])
+        .map_err(|err| format!("{:#?}", err))?;
+    Ok(Uint8Array::from(&rln_witness[..]))
+}
+
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[wasm_bindgen(js_name = insertMember)]
+pub fn wasm_set_next_leaf(ctx: *mut RLNWrapper, input: Uint8Array) -> Result<(), String> {
+    call_with_error_msg!(
+        ctx,
+        set_next_leaf,
+        "could not insert member into merkle tree".to_string(),
+        &input.to_vec()[..]
+    )
+}
+
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[wasm_bindgen(js_name = setLeavesFrom)]
+pub fn wasm_set_leaves_from(
+    ctx: *mut RLNWrapper,
+    index: usize,
+    input: Uint8Array,
+) -> Result<(), String> {
+    call_with_error_msg!(
+        ctx,
+        set_leaves_from,
+        "could not set multiple leaves".to_string(),
+        index,
+        &*input.to_vec()
+    )
+}
+
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[wasm_bindgen(js_name = deleteLeaf)]
+pub fn wasm_delete_leaf(ctx: *mut RLNWrapper, index: usize) -> Result<(), String> {
+    call_with_error_msg!(ctx, delete_leaf, "could not delete leaf".to_string(), index)
+}
+
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[wasm_bindgen(js_name = setMetadata)]
+pub fn wasm_set_metadata(ctx: *mut RLNWrapper, input: Uint8Array) -> Result<(), String> {
+    call_with_error_msg!(
+        ctx,
+        set_metadata,
+        "could not set metadata".to_string(),
+        &*input.to_vec()
+    )
+}
+
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[wasm_bindgen(js_name = getMetadata)]
+pub fn wasm_get_metadata(ctx: *mut RLNWrapper) -> Result<Uint8Array, String> {
+    call_with_output_and_error_msg!(ctx, get_metadata, "could not get metadata".to_string())
+}
+
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[wasm_bindgen(js_name = initTreeWithLeaves)]
+pub fn wasm_init_tree_with_leaves(ctx: *mut RLNWrapper, input: Uint8Array) -> Result<(), String> {
+    call_with_error_msg!(
+        ctx,
+        init_tree_with_leaves,
+        "could not init merkle tree".to_string(),
+        &*input.to_vec()
+    )
+}
+
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[wasm_bindgen(js_name = RLNWitnessToJson)]
 pub fn rln_witness_to_json(
     ctx: *mut RLNWrapper,
     serialized_witness: Uint8Array,
 ) -> Result<Object, String> {
-    let inputs = call!(
-        ctx,
-        get_rln_witness_bigint_json,
-        &serialized_witness.to_vec()[..]
-    )
-    .map_err(|err| err.to_string())?;
+    let inputs = call!(ctx, get_rln_witness_json, &serialized_witness.to_vec()[..])
+        .map_err(|err| err.to_string())?;
     let js_value = serde_wasm_bindgen::to_value(&inputs).map_err(|err| err.to_string())?;
     Object::from_entries(&js_value).map_err(|err| format!("{:#?}", err))
 }
@@ -289,6 +358,17 @@ pub fn wasm_recover_id_secret(
     )
 }
 
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[wasm_bindgen(js_name = verifyRLNProof)]
+pub fn wasm_verify_rln_proof(ctx: *const RLNWrapper, proof: Uint8Array) -> Result<bool, String> {
+    call_bool_method_with_error_msg!(
+        ctx,
+        verify_rln_proof,
+        "error while verifying rln proof".to_string(),
+        &proof.to_vec()[..]
+    )
+}
+
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[wasm_bindgen(js_name = verifyWithRoots)]
 pub fn wasm_verify_with_roots(
@@ -305,6 +385,12 @@ pub fn wasm_verify_with_roots(
     )
 }
 
+#[allow(clippy::not_unsafe_ptr_arg_deref)]
+#[wasm_bindgen(js_name = getRoot)]
+pub fn wasm_get_root(ctx: *const RLNWrapper) -> Result<Uint8Array, String> {
+    call_with_output_and_error_msg!(ctx, get_root, "could not obtain root")
+}
+
 #[wasm_bindgen(js_name = hash)]
 pub fn wasm_hash(input: Uint8Array) -> Result<Uint8Array, String> {
     fn_call_with_output_and_error_msg!(hash, "could not generate hash", &input.to_vec()[..])

rln-wasm/tests/rln-wasm.rs

@@ -3,17 +3,11 @@
 #[cfg(test)]
 mod tests {
     use js_sys::{BigInt as JsBigInt, Object, Uint8Array};
-    use rln::circuit::{Fr, TEST_TREE_HEIGHT};
-    use rln::hashers::{hash_to_field, poseidon_hash};
-    use rln::utils::{bytes_le_to_fr, fr_to_bytes_le, normalize_usize};
+    use rln::circuit::TEST_TREE_HEIGHT;
+    use rln::utils::normalize_usize;
     use rln_wasm::*;
-    use rln::poseidon_tree::PoseidonTree;
-    use rln::utils::vec_fr_to_bytes_le;
     use wasm_bindgen::{prelude::*, JsValue};
     use wasm_bindgen_test::wasm_bindgen_test;
-    use zerokit_utils::merkle_tree::merkle_tree::ZerokitMerkleTree;
-    use zerokit_utils::ZerokitMerkleProof;
-     use rln::utils::vec_u8_to_bytes_le;
 
     #[wasm_bindgen(module = "src/utils.js")]
     extern "C" {
@@ -30,58 +24,45 @@ mod tests {
         let circom_path = format!("../rln/resources/tree_height_{TEST_TREE_HEIGHT}/rln.wasm");
         let zkey_path = format!("../rln/resources/tree_height_{TEST_TREE_HEIGHT}/rln_final.zkey");
         let vk_path =
-            format!("../rln/resources/tree_height_{TEST_TREE_HEIGHT}/verification_key.arkvkey");
+            format!("../rln/resources/tree_height_{TEST_TREE_HEIGHT}/verification_key.json");
         let zkey = read_file(&zkey_path).unwrap();
         let vk = read_file(&vk_path).unwrap();
 
         // Creating an instance of RLN
-        let rln_instance = wasm_new(zkey, vk).unwrap();
-
-        let mut tree = PoseidonTree::default(TEST_TREE_HEIGHT).unwrap();
+        let rln_instance = wasm_new(tree_height, zkey, vk).unwrap();
 
         // Creating membership key
         let mem_keys = wasm_key_gen(rln_instance).unwrap();
-        let id_key = mem_keys.subarray(0, 32);
-        let id_commitment = mem_keys.subarray(32, 64);
+        let idkey = mem_keys.subarray(0, 32);
+        let idcommitment = mem_keys.subarray(32, 64);
+
+        // Insert PK
+        wasm_set_next_leaf(rln_instance, idcommitment).unwrap();
 
         // Prepare the message
-        let signal = b"Hello World";
+        let signal = "Hello World".as_bytes();
 
-        let identity_index = tree.leaves_set();
-        // Setting up the epoch and rln_identifier
-        let epoch = hash_to_field(b"test-epoch");
-        let rln_identifier = hash_to_field(b"test-rln-identifier");
-
-        let external_nullifier = poseidon_hash(&[epoch, rln_identifier]);
-        let external_nullifier = fr_to_bytes_le(&external_nullifier);
-
-        let user_message_limit = Fr::from(100);
-        let message_id = fr_to_bytes_le(&Fr::from(0));
-
-        let (id_commitment_fr, _) = bytes_le_to_fr(&id_commitment.to_vec()[..]);
-        let rate_commitment = poseidon_hash(&[id_commitment_fr, user_message_limit]);
-        tree.update_next(rate_commitment).unwrap();
-
-        let x = hash_to_field(signal);
-        let merkle_proof = tree.proof(identity_index).expect("proof should exist");
-        let path_elements = merkle_proof.get_path_elements();
-        let identity_path_index = merkle_proof.get_path_index();
+        // Setting up the epoch (With 0s for the test)
+        let epoch = Uint8Array::new_with_length(32);
+        epoch.fill(0, 0, 32);
 
+        let identity_index: usize = 0;
 
         // Serializing the message
         let mut serialized_vec: Vec<u8> = Vec::new();
-        serialized_vec.append(&mut id_key.to_vec());
-        serialized_vec.append(&mut fr_to_bytes_le(&user_message_limit).to_vec());
-        serialized_vec.append(&mut message_id.to_vec());
-        serialized_vec.append(&mut vec_fr_to_bytes_le(&path_elements).unwrap());
-        serialized_vec.append(&mut vec_u8_to_bytes_le(&identity_path_index).unwrap());
-        serialized_vec.append(&mut fr_to_bytes_le(&x));
-        serialized_vec.append(&mut external_nullifier.to_vec());
+        serialized_vec.append(&mut idkey.to_vec());
+        serialized_vec.append(&mut normalize_usize(identity_index));
+        serialized_vec.append(&mut epoch.to_vec());
+        serialized_vec.append(&mut normalize_usize(signal.len()));
+        serialized_vec.append(&mut signal.to_vec());
         let serialized_message = Uint8Array::from(&serialized_vec[..]);
 
+        let serialized_rln_witness =
+            wasm_get_serialized_rln_witness(rln_instance, serialized_message).unwrap();
+
         // Obtaining inputs that should be sent to circom witness calculator
         let json_inputs =
-            rln_witness_to_json(rln_instance, serialized_message.clone()).unwrap();
+            rln_witness_to_json(rln_instance, serialized_rln_witness.clone()).unwrap();
 
         // Calculating witness with JS
         // (Using a JSON since wasm_bindgen does not like Result<Vec<JsBigInt>,JsValue>)
@@ -101,7 +82,7 @@ mod tests {
         let proof = generate_rln_proof_with_witness(
             rln_instance,
             calculated_witness.into(),
-            serialized_message,
+            serialized_rln_witness,
         )
         .unwrap();
 
@@ -111,13 +92,44 @@ mod tests {
         proof_bytes.append(&mut signal.to_vec());
         let proof_with_signal = Uint8Array::from(&proof_bytes[..]);
 
+        // Validate Proof
+        let is_proof_valid = wasm_verify_rln_proof(rln_instance, proof_with_signal);
+
+        assert!(
+            is_proof_valid.unwrap(),
+            "validating proof generated with wasm failed"
+        );
+
         // Validating Proof with Roots
-        let root = tree.root();
-        let root_le = fr_to_bytes_le(&root);
-        let roots = Uint8Array::from(&root_le[..]);
+        let root = wasm_get_root(rln_instance).unwrap();
+        let roots = Uint8Array::from(&root.to_vec()[..]);
         let proof_with_signal = Uint8Array::from(&proof_bytes[..]);
 
         let is_proof_valid = wasm_verify_with_roots(rln_instance, proof_with_signal, roots);
         assert!(is_proof_valid.unwrap(), "verifying proof with roots failed");
     }
+
+    #[wasm_bindgen_test]
+    fn test_metadata() {
+        let tree_height = TEST_TREE_HEIGHT;
+        let circom_path = format!("../rln/resources/tree_height_{TEST_TREE_HEIGHT}/rln.wasm");
+        let zkey_path = format!("../rln/resources/tree_height_{TEST_TREE_HEIGHT}/rln_final.zkey");
+        let vk_path =
+            format!("../rln/resources/tree_height_{TEST_TREE_HEIGHT}/verification_key.json");
+        let zkey = read_file(&zkey_path).unwrap();
+        let vk = read_file(&vk_path).unwrap();
+
+        // Creating an instance of RLN
+        let rln_instance = wasm_new(tree_height, zkey, vk).unwrap();
+
+
+        let test_metadata = Uint8Array::new(&JsValue::from_str("test"));
+        // Inserting random metadata
+        wasm_set_metadata(rln_instance, test_metadata.clone()).unwrap();
+
+        // Getting metadata
+        let metadata = wasm_get_metadata(rln_instance).unwrap();
+
+        assert_eq!(metadata.to_vec(), test_metadata.to_vec());
+    }
 }

rln/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rln"
-version = "0.6.1"
+version = "0.3.6"
 edition = "2021"
 license = "MIT OR Apache-2.0"
 description = "APIs to manage, compute and verify zkSNARK proofs and RLN primitives"
@@ -19,20 +19,13 @@ doctest = false
 [dependencies]
 # ZKP Generation
 ark-ec = { version = "=0.4.1", default-features = false }
-ark-ff = { version = "=0.4.1", default-features = false, features = ["asm"] }
+ark-ff = { version = "=0.4.1", default-features = false, features = [ "asm"] }
 ark-std = { version = "=0.4.0", default-features = false }
 ark-bn254 = { version = "=0.4.0" }
-ark-groth16 = { version = "=0.4.0", features = [
-    "parallel",
-], default-features = false }
-ark-relations = { version = "=0.4.0", default-features = false, features = [
-    "std",
-] }
+ark-groth16 = { version = "=0.4.0", features = ["parallel"], default-features = false }
+ark-relations = { version = "=0.4.0", default-features = false, features = [ "std" ] }
 ark-serialize = { version = "=0.4.1", default-features = false }
-ark-circom = { version = "=0.1.0", default-features = false, features = [
-    "circom-2",
-] }
-ark-zkey = { version = "0.1.0", optional = true, default-features = false }
+ark-circom = { version = "=0.1.0", default-features = false, features = ["circom-2"] }
 
 # WASM
 wasmer = { version = "=2.3.0", default-features = false }
@@ -43,23 +36,19 @@ thiserror = "=1.0.39"
 
 # utilities
 cfg-if = "=1.0"
-num-bigint = { version = "=0.4.3", default-features = false, features = [
-    "rand",
-] }
+num-bigint = { version = "=0.4.3", default-features = false, features = ["rand"] }
 num-traits = "=0.2.15"
 once_cell = "=1.17.1"
-lazy_static = "=1.4.0"
 rand = "=0.8.5"
 rand_chacha = "=0.3.1"
 tiny-keccak = { version = "=2.0.2", features = ["keccak"] }
-utils = { package = "zerokit_utils", version = "=0.5.1", path = "../utils/", default-features = false }
-
+utils = { package = "zerokit_utils", version = "=0.3.2", path = "../utils/", default-features = false }
 
 # serialization
 serde_json = "=1.0.96"
 serde = { version = "=1.0.163", features = ["derive"] }
 
-document-features = { version = "=0.2.10", optional = true }
+include_dir = "=0.7.3"
 
 [dev-dependencies]
 sled = "=0.34.7"
@@ -67,17 +56,9 @@ criterion = { version = "=0.4.0", features = ["html_reports"] }
 
 [features]
 default = ["parallel", "wasmer/sys-default", "pmtree-ft"]
-parallel = [
-    "ark-ec/parallel",
-    "ark-ff/parallel",
-    "ark-std/parallel",
-    "ark-groth16/parallel",
-    "utils/parallel",
-]
+parallel = ["ark-ec/parallel", "ark-ff/parallel", "ark-std/parallel", "ark-groth16/parallel", "utils/parallel"]
 wasm = ["wasmer/js", "wasmer/std"]
 fullmerkletree = ["default"]
-arkzkey = ["ark-zkey"]
-stateless = []
 
 # Note: pmtree feature is still experimental
 pmtree-ft = ["utils/pmtree-ft"]
@@ -85,23 +66,3 @@ pmtree-ft = ["utils/pmtree-ft"]
 [[bench]]
 name = "pmtree_benchmark"
 harness = false
-
-[[bench]]
-name = "circuit_loading_benchmark"
-harness = false
-
-[[bench]]
-name = "circuit_loading_arkzkey_benchmark"
-harness = false
-required-features = ["arkzkey"]
-
-[[bench]]
-name = "circuit_deser_benchmark"
-harness = false
-
-[[bench]]
-name = "poseidon_tree_benchmark"
-harness = false
-
-[package.metadata.docs.rs]
-all-features = true

rln/Makefile.toml

@@ -2,18 +2,10 @@
 command = "cargo"
 args = ["build", "--release"]
 
-[tasks.test_default]
+[tasks.test]
 command = "cargo"
 args = ["test", "--release"]
 
-[tasks.test_stateless]
-command = "cargo"
-args = ["test", "--release", "--features", "stateless"]
-
-[tasks.test_arkzkey]
-command = "cargo"
-args = ["test", "--release", "--features", "arkzkey"]
-
 [tasks.bench]
 command = "cargo"
 args = ["bench"]

rln/README.md

@@ -3,7 +3,6 @@
 This module provides APIs to manage, compute and verify [RLN](https://rfc.vac.dev/spec/32/) zkSNARK proofs and RLN primitives.
 
 ## Pre-requisites
-
 ### Install dependencies and clone repo
 
 ```sh
@@ -15,7 +14,6 @@ cd zerokit/rln
 ### Build and Test
 
 To build and test, run the following commands within the module folder
-
 ```bash
 cargo make build
 cargo make test
@@ -23,11 +21,11 @@ cargo make test
 
 ### Compile ZK circuits
 
-The `rln` (https://github.com/rate-limiting-nullifier/circom-rln) repository, which contains the RLN circuit implementation is a submodule of zerokit RLN.
+The `rln` (https://github.com/privacy-scaling-explorations/rln) repository, which contains the RLN circuit implementation is a submodule of zerokit RLN. 
 
 To compile the RLN circuit
 
-```sh
+``` sh
 # Update submodules
 git submodule update --init --recursive
 
@@ -54,10 +52,11 @@ include "./rln-base.circom";
 component main {public [x, epoch, rln_identifier ]} = RLN(N);
 ```
 
-However, if `N` is too big, this might require a bigger Powers of Tau ceremony than the one hardcoded in `./scripts/build-circuits.sh`, which is `2^14`.
+However, if `N` is too big, this might require a bigger Powers of Tau ceremony than the one hardcoded in `./scripts/build-circuits.sh`, which is `2^14`. 
 In such case we refer to the official [Circom documentation](https://docs.circom.io/getting-started/proving-circuits/#powers-of-tau) for instructions on how to run an appropriate Powers of Tau ceremony and Phase 2 in order to compile the desired circuit.
 
-Currently, the `rln` module comes with 2 [pre-compiled](https://github.com/vacp2p/zerokit/tree/master/rln/resources) RLN circuits having Merkle tree of height `20` and `32`, respectively.
+
+Currently, the `rln` module comes with three [pre-compiled](https://github.com/vacp2p/zerokit/tree/master/rln/resources) RLN circuits having Merkle tree of height `15`, `19` and `20`, respectively.
 
 ## Getting started
 
@@ -74,7 +73,7 @@ rln = { git = "https://github.com/vacp2p/zerokit" }
 
 First, we need to create a RLN object for a chosen input Merkle tree size.
 
-Note that we need to pass to RLN object constructor the path where the circuit (`rln.wasm`, built for the input tree size), the corresponding proving key (`rln_final.zkey`) or (`rln_final.arkzkey`) and verification key (`verification_key.arkvkey`, optional) are found.
+Note that we need to pass to RLN object constructor the path where the circuit (`rln.wasm`, built for the input tree size), the corresponding proving key (`rln_final.zkey`) and verification key (`verification_key.json`, optional) are found.
 
 In the following we will use [cursors](https://doc.rust-lang.org/std/io/struct.Cursor.html) as readers/writers for interfacing with RLN public APIs.
 
@@ -83,14 +82,14 @@ use rln::protocol::*;
 use rln::public::*;
 use std::io::Cursor;
 
-// We set the RLN parameters:
+// We set the RLN parameters: 
 // - the tree height;
-// - the tree config, if it is not defined, the default value will be set
+// - the circuit resource folder (requires a trailing "/").
 let tree_height = 20;
-let input = Cursor::new(json!({}).to_string());
+let resources = Cursor::new("../zerokit/rln/resources/tree_height_20/");
 
 // We create a new RLN instance
-let mut rln = RLN::new(tree_height, input);
+let mut rln = RLN::new(tree_height, resources);
 ```
 
 ### Generate an identity keypair
@@ -103,62 +102,50 @@ let mut buffer = Cursor::new(Vec::<u8>::new());
 rln.key_gen(&mut buffer).unwrap();
 
 // We deserialize the keygen output to obtain
-// the identity_secret and id_commitment
+// the identiy_secret and id_commitment
 let (identity_secret_hash, id_commitment) = deserialize_identity_pair(buffer.into_inner());
 ```
 
-### Add Rate commitment to the RLN Merkle tree
+### Add ID commitment to the RLN Merkle tree
 
 ```rust
 // We define the tree index where id_commitment will be added
 let id_index = 10;
-let user_message_limit = 10;
 
 // We serialize id_commitment and pass it to set_leaf
-let rate_commitment = poseidon_hash(&[id_commitment, user_message_limit]);
-let mut buffer = Cursor::new(serialize_field_element(rate_commitment));
+let mut buffer = Cursor::new(serialize_field_element(id_commitment));
 rln.set_leaf(id_index, &mut buffer).unwrap();
 ```
 
 Note that when tree leaves are not explicitly set by the user (in this example, all those with index less and greater than `10`), their values is set to an hardcoded default (all-`0` bytes in current implementation).
 
-### Set external nullifier
+### Set epoch
 
-The `external nullifier` includes two parameters.
-
-The first one is `epoch` and it's used to identify messages received in a certain time frame. It usually corresponds to the current UNIX time but can also be set to a random value or generated by a seed, provided that it corresponds to a field element.
-
-The second one is `rln_identifier` and it's used to prevent a RLN ZK proof generated for one application to be re-used in another one.
+The epoch, sometimes referred to as _external nullifier_, is used to identify messages received in a certain time frame. It usually corresponds to the current UNIX time but can also be set to a random value or generated by a seed, provided that it corresponds to a field element.
 
 ```rust
 // We generate epoch from a date seed and we ensure is
 // mapped to a field element by hashing-to-field its content
 let epoch = hash_to_field(b"Today at noon, this year");
-// We generate rln_identifier from a date seed and we ensure is
-// mapped to a field element by hashing-to-field its content
-let rln_identifier = hash_to_field(b"test-rln-identifier");
-
-let external_nullifier = poseidon_hash(&[epoch, rln_identifier]);
 ```
-
 ### Set signal
 
 The signal is the message for which we are computing a RLN proof.
 
 ```rust
-// We set our signal
+// We set our signal 
 let signal = b"RLN is awesome";
 ```
 
 ### Generate a RLN proof
 
-We prepare the input to the proof generation routine.
+We prepare the input to the proof generation routine. 
 
-Input buffer is serialized as `[ identity_key | id_index | external_nullifier | user_message_limit | message_id | signal_len | signal ]`.
+Input buffer is serialized as `[ identity_key | id_index | epoch | signal_len | signal ]`.
 
 ```rust
 // We prepare input to the proof generation routine
-let proof_input = prepare_prove_input(identity_secret_hash, id_index, external_nullifier, signal);
+let proof_input = prepare_prove_input(identity_secret_hash, id_index, epoch, signal);
 ```
 
 We are now ready to generate a RLN ZK proof along with the _public outputs_ of the ZK circuit evaluation.
@@ -175,11 +162,12 @@ rln.generate_rln_proof(&mut in_buffer, &mut out_buffer)
 let proof_data = out_buffer.into_inner();
 ```
 
-The byte vector `proof_data` is serialized as `[ zk-proof | tree_root | external_nullifier | share_x | share_y | nullifier ]`.
+The byte vector `proof_data` is serialized as `[ zk-proof | tree_root | epoch | share_x | share_y | nullifier | rln_identifier ]`.
+
 
 ### Verify a RLN proof
 
-We prepare the input to the proof verification routine.
+We prepare the input to the proof verification routine. 
 
 Input buffer is serialized as `[proof_data | signal_len | signal ]`, where `proof_data` is (computed as) the output obtained by `generate_rln_proof`.
 
@@ -192,21 +180,17 @@ let mut in_buffer = Cursor::new(verify_data);
 let verified = rln.verify(&mut in_buffer).unwrap();
 ```
 
-We check if the proof verification was successful:
-
+We check if the proof verification was successful: 
 ```rust
 // We ensure the proof is valid
 assert!(verified);
 ```
 
 ## Get involved!
-
 Zerokit RLN public and FFI APIs allow interaction with many more features than what briefly showcased above.
 
 We invite you to check our API documentation by running
-
 ```rust
 cargo doc --no-deps
 ```
-
-and look at unit tests to have an hint on how to interface and use them.
+and look at unit tests to have an hint on how to interface and use them.

rln/benches/circuit_deser_benchmark.rs

@@ -1,22 +0,0 @@
-use criterion::{criterion_group, criterion_main, Criterion};
-use rln::circuit::{vk_from_ark_serialized, VK_BYTES};
-
-// Here we benchmark how long the deserialization of the
-// verifying_key takes, only testing the json => verifying_key conversion,
-// and skipping conversion from bytes => string => serde_json::Value
-pub fn vk_deserialize_benchmark(c: &mut Criterion) {
-    let vk = VK_BYTES;
-
-    c.bench_function("vk::vk_from_ark_serialized", |b| {
-        b.iter(|| {
-            let _ = vk_from_ark_serialized(vk);
-        })
-    });
-}
-
-criterion_group! {
-    name = benches;
-    config = Criterion::default().measurement_time(std::time::Duration::from_secs(10));
-    targets = vk_deserialize_benchmark
-}
-criterion_main!(benches);

rln/benches/circuit_loading_arkzkey_benchmark.rs

@@ -1,43 +0,0 @@
-use criterion::{criterion_group, criterion_main, Criterion};
-use rln::circuit::{
-    read_arkzkey_from_bytes_compressed, read_arkzkey_from_bytes_uncompressed, ARKZKEY_BYTES,
-    ARKZKEY_BYTES_UNCOMPR,
-};
-
-pub fn uncompressed_bench(c: &mut Criterion) {
-    let arkzkey = ARKZKEY_BYTES_UNCOMPR.to_vec();
-    let size = arkzkey.len() as f32;
-    println!(
-        "Size of uncompressed arkzkey: {:.2?} MB",
-        size / 1024.0 / 1024.0
-    );
-
-    c.bench_function("arkzkey::arkzkey_from_raw_uncompressed", |b| {
-        b.iter(|| {
-            let r = read_arkzkey_from_bytes_uncompressed(&arkzkey);
-            assert_eq!(r.is_ok(), true);
-        })
-    });
-}
-pub fn compressed_bench(c: &mut Criterion) {
-    let arkzkey = ARKZKEY_BYTES.to_vec();
-    let size = arkzkey.len() as f32;
-    println!(
-        "Size of compressed arkzkey: {:.2?} MB",
-        size / 1024.0 / 1024.0
-    );
-
-    c.bench_function("arkzkey::arkzkey_from_raw_compressed", |b| {
-        b.iter(|| {
-            let r = read_arkzkey_from_bytes_compressed(&arkzkey);
-            assert_eq!(r.is_ok(), true);
-        })
-    });
-}
-
-criterion_group! {
-    name = benches;
-    config = Criterion::default().measurement_time(std::time::Duration::from_secs(250));
-    targets = uncompressed_bench, compressed_bench
-}
-criterion_main!(benches);

rln/benches/circuit_loading_benchmark.rs

@@ -1,24 +0,0 @@
-use ark_circom::read_zkey;
-use criterion::{criterion_group, criterion_main, Criterion};
-use std::io::Cursor;
-
-pub fn zkey_load_benchmark(c: &mut Criterion) {
-    let zkey = rln::circuit::ZKEY_BYTES.to_vec();
-    let size = zkey.len() as f32;
-    println!("Size of zkey: {:.2?} MB", size / 1024.0 / 1024.0);
-
-    c.bench_function("zkey::zkey_from_raw", |b| {
-        b.iter(|| {
-            let mut reader = Cursor::new(zkey.clone());
-            let r = read_zkey(&mut reader);
-            assert_eq!(r.is_ok(), true);
-        })
-    });
-}
-
-criterion_group! {
-    name = benches;
-    config = Criterion::default().measurement_time(std::time::Duration::from_secs(250));
-    targets = zkey_load_benchmark
-}
-criterion_main!(benches);

rln/benches/pmtree_benchmark.rs

@@ -1,7 +1,8 @@
 use criterion::{criterion_group, criterion_main, Criterion};
-use rln::{circuit::Fr, pm_tree_adapter::PmTree};
 use utils::ZerokitMerkleTree;
 
+use rln::{circuit::Fr, pm_tree_adapter::PmTree};
+
 pub fn pmtree_benchmark(c: &mut Criterion) {
     let mut tree = PmTree::default(2).unwrap();
 
@@ -37,19 +38,6 @@ pub fn pmtree_benchmark(c: &mut Criterion) {
             tree.get(0).unwrap();
         })
     });
-
-    // check intermediate node getter which required additional computation of sub root index
-    c.bench_function("Pmtree::get_subtree_root", |b| {
-        b.iter(|| {
-            tree.get_subtree_root(1, 0).unwrap();
-        })
-    });
-
-    c.bench_function("Pmtree::get_empty_leaves_indices", |b| {
-        b.iter(|| {
-            tree.get_empty_leaves_indices();
-        })
-    });
 }
 
 criterion_group!(benches, pmtree_benchmark);

rln/benches/poseidon_tree_benchmark.rs

@@ -1,79 +0,0 @@
-use criterion::{criterion_group, criterion_main, BenchmarkId, Criterion};
-use rln::{
-    circuit::{Fr, TEST_TREE_HEIGHT},
-    hashers::PoseidonHash,
-};
-use utils::{FullMerkleTree, OptimalMerkleTree, ZerokitMerkleTree};
-
-pub fn get_leaves(n: u32) -> Vec<Fr> {
-    (0..n).map(|s| Fr::from(s)).collect()
-}
-
-pub fn optimal_merkle_tree_poseidon_benchmark(c: &mut Criterion) {
-    c.bench_function("OptimalMerkleTree::<Poseidon>::full_height_gen", |b| {
-        b.iter(|| {
-            OptimalMerkleTree::<PoseidonHash>::default(TEST_TREE_HEIGHT).unwrap();
-        })
-    });
-
-    let mut group = c.benchmark_group("Set");
-    for &n in [1u32, 10, 100].iter() {
-        let leaves = get_leaves(n);
-
-        let mut tree = OptimalMerkleTree::<PoseidonHash>::default(TEST_TREE_HEIGHT).unwrap();
-        group.bench_function(
-            BenchmarkId::new("OptimalMerkleTree::<Poseidon>::set", n),
-            |b| {
-                b.iter(|| {
-                    for (i, l) in leaves.iter().enumerate() {
-                        let _ = tree.set(i, *l);
-                    }
-                })
-            },
-        );
-
-        group.bench_function(
-            BenchmarkId::new("OptimalMerkleTree::<Poseidon>::set_range", n),
-            |b| b.iter(|| tree.set_range(0, leaves.iter().cloned())),
-        );
-    }
-    group.finish();
-}
-
-pub fn full_merkle_tree_poseidon_benchmark(c: &mut Criterion) {
-    c.bench_function("FullMerkleTree::<Poseidon>::full_height_gen", |b| {
-        b.iter(|| {
-            FullMerkleTree::<PoseidonHash>::default(TEST_TREE_HEIGHT).unwrap();
-        })
-    });
-
-    let mut group = c.benchmark_group("Set");
-    for &n in [1u32, 10, 100].iter() {
-        let leaves = get_leaves(n);
-
-        let mut tree = FullMerkleTree::<PoseidonHash>::default(TEST_TREE_HEIGHT).unwrap();
-        group.bench_function(
-            BenchmarkId::new("FullMerkleTree::<Poseidon>::set", n),
-            |b| {
-                b.iter(|| {
-                    for (i, l) in leaves.iter().enumerate() {
-                        let _ = tree.set(i, *l);
-                    }
-                })
-            },
-        );
-
-        group.bench_function(
-            BenchmarkId::new("FullMerkleTree::<Poseidon>::set_range", n),
-            |b| b.iter(|| tree.set_range(0, leaves.iter().cloned())),
-        );
-    }
-    group.finish();
-}
-
-criterion_group!(
-    benches,
-    optimal_merkle_tree_poseidon_benchmark,
-    full_merkle_tree_poseidon_benchmark
-);
-criterion_main!(benches);

rln/resources/tree_height_15/verification_key.json

@@ -0,0 +1,119 @@
+{
+ "protocol": "groth16",
+ "curve": "bn128",
+ "nPublic": 6,
+ "vk_alpha_1": [
+  "20124996762962216725442980738609010303800849578410091356605067053491763969391",
+  "9118593021526896828671519912099489027245924097793322973632351264852174143923",
+  "1"
+ ],
+ "vk_beta_2": [
+  [
+   "4693952934005375501364248788849686435240706020501681709396105298107971354382",
+   "14346958885444710485362620645446987998958218205939139994511461437152241966681"
+  ],
+  [
+   "16851772916911573982706166384196538392731905827088356034885868448550849804972",
+   "823612331030938060799959717749043047845343400798220427319188951998582076532"
+  ],
+  [
+   "1",
+   "0"
+  ]
+ ],
+ "vk_gamma_2": [
+  [
+   "10857046999023057135944570762232829481370756359578518086990519993285655852781",
+   "11559732032986387107991004021392285783925812861821192530917403151452391805634"
+  ],
+  [
+   "8495653923123431417604973247489272438418190587263600148770280649306958101930",
+   "4082367875863433681332203403145435568316851327593401208105741076214120093531"
+  ],
+  [
+   "1",
+   "0"
+  ]
+ ],
+ "vk_delta_2": [
+  [
+   "1361919643088555407518565462732544232965454074504004321739078395285189557133",
+   "20823246840633598579879223919854294301857184404415306521912631074982696570306"
+  ],
+  [
+   "7088590198103342249937795923142619828109070290720888704402714617857746884833",
+   "8191367139632195506244169264298620546181137131063303219908889318280111188437"
+  ],
+  [
+   "1",
+   "0"
+  ]
+ ],
+ "vk_alphabeta_12": [
+  [
+   [
+    "12608968655665301215455851857466367636344427685631271961542642719683786103711",
+    "9849575605876329747382930567422916152871921500826003490242628251047652318086"
+   ],
+   [
+    "6322029441245076030714726551623552073612922718416871603535535085523083939021",
+    "8700115492541474338049149013125102281865518624059015445617546140629435818912"
+   ],
+   [
+    "10674973475340072635573101639867487770811074181475255667220644196793546640210",
+    "2926286967251299230490668407790788696102889214647256022788211245826267484824"
+   ]
+  ],
+  [
+   [
+    "9660441540778523475944706619139394922744328902833875392144658911530830074820",
+    "19548113127774514328631808547691096362144426239827206966690021428110281506546"
+   ],
+   [
+    "1870837942477655969123169532603615788122896469891695773961478956740992497097",
+    "12536105729661705698805725105036536744930776470051238187456307227425796690780"
+   ],
+   [
+    "21811903352654147452884857281720047789720483752548991551595462057142824037334",
+    "19021616763967199151052893283384285352200445499680068407023236283004353578353"
+   ]
+  ]
+ ],
+ "IC": [
+  [
+   "17643142412395322664866141827318671249236739056291610144830020671604112279111",
+   "13273439661778801509295280274403992505521239023074387826870538372514206268318",
+   "1"
+  ],
+  [
+   "12325966053136615826793633393742326952102053533176311103856731330114882211366",
+   "6439956820140153832120005353467272867287237423425778281905068783317736451260",
+   "1"
+  ],
+  [
+   "20405310272367450124741832665322768131899487413829191383721623069139009993137",
+   "21336772016824870564600007750206596010566056069977718959140462128560786193566",
+   "1"
+  ],
+  [
+   "4007669092231576644992949839487535590075070172447826102934640178940614212519",
+   "7597503385395289202372182678960254605827199004598882158153019657732525465207",
+   "1"
+  ],
+  [
+   "4545695279389338758267531646940033299700127241196839077811942492841603458462",
+   "6635771967009274882904456432128877995932122611166121203658485990305433499873",
+   "1"
+  ],
+  [
+   "7876954805169515500747828488548350352651069599547377092970620945851311591012",
+   "7571431725691513008054581132582771105743462534789373657638701712901679323321",
+   "1"
+  ],
+  [
+   "5563973122249220346301217166900152021860462617567141574881706390202619333219",
+   "5147729144109676590873823097632042430451708874867871369293332620382492068692",
+   "1"
+  ]
+ ]
+}

rln/resources/tree_height_19/verification_key.json

@@ -0,0 +1,119 @@
+{
+ "protocol": "groth16",
+ "curve": "bn128",
+ "nPublic": 6,
+ "vk_alpha_1": [
+  "20124996762962216725442980738609010303800849578410091356605067053491763969391",
+  "9118593021526896828671519912099489027245924097793322973632351264852174143923",
+  "1"
+ ],
+ "vk_beta_2": [
+  [
+   "4693952934005375501364248788849686435240706020501681709396105298107971354382",
+   "14346958885444710485362620645446987998958218205939139994511461437152241966681"
+  ],
+  [
+   "16851772916911573982706166384196538392731905827088356034885868448550849804972",
+   "823612331030938060799959717749043047845343400798220427319188951998582076532"
+  ],
+  [
+   "1",
+   "0"
+  ]
+ ],
+ "vk_gamma_2": [
+  [
+   "10857046999023057135944570762232829481370756359578518086990519993285655852781",
+   "11559732032986387107991004021392285783925812861821192530917403151452391805634"
+  ],
+  [
+   "8495653923123431417604973247489272438418190587263600148770280649306958101930",
+   "4082367875863433681332203403145435568316851327593401208105741076214120093531"
+  ],
+  [
+   "1",
+   "0"
+  ]
+ ],
+ "vk_delta_2": [
+  [
+   "16125279975606773676640811113051624654121459921695914044301154938920321009721",
+   "14844345250267029614093295465313288254479124604567709177260777529651293576873"
+  ],
+  [
+   "20349277326920398483890518242229158117668855310237215044647746783223259766294",
+   "19338776107510040969200058390413661029003750817172740054990168933780935479540"
+  ],
+  [
+   "1",
+   "0"
+  ]
+ ],
+ "vk_alphabeta_12": [
+  [
+   [
+    "12608968655665301215455851857466367636344427685631271961542642719683786103711",
+    "9849575605876329747382930567422916152871921500826003490242628251047652318086"
+   ],
+   [
+    "6322029441245076030714726551623552073612922718416871603535535085523083939021",
+    "8700115492541474338049149013125102281865518624059015445617546140629435818912"
+   ],
+   [
+    "10674973475340072635573101639867487770811074181475255667220644196793546640210",
+    "2926286967251299230490668407790788696102889214647256022788211245826267484824"
+   ]
+  ],
+  [
+   [
+    "9660441540778523475944706619139394922744328902833875392144658911530830074820",
+    "19548113127774514328631808547691096362144426239827206966690021428110281506546"
+   ],
+   [
+    "1870837942477655969123169532603615788122896469891695773961478956740992497097",
+    "12536105729661705698805725105036536744930776470051238187456307227425796690780"
+   ],
+   [
+    "21811903352654147452884857281720047789720483752548991551595462057142824037334",
+    "19021616763967199151052893283384285352200445499680068407023236283004353578353"
+   ]
+  ]
+ ],
+ "IC": [
+  [
+   "5645604624116784480262312750033349186912223090668673154853165165224747369512",
+   "5656337658385597582701340925622307146226708710361427687425735166776477641124",
+   "1"
+  ],
+  [
+   "8216930132302312821663833393171053651364962198587857550991047765311607638330",
+   "19934865864074163318938688021560358348660709566570123384268356491416384822148",
+   "1"
+  ],
+  [
+   "11046959016591768534564223076484566731774575511709349452804727872479525392631",
+   "9401797690410912638766111919371607085248054251975419812613989999345815833269",
+   "1"
+  ],
+  [
+   "13216594148914395028254776738842380005944817065680915990743659996725367876414",
+   "11541283802841111343960351782994043892623551381569479006737253908665900144087",
+   "1"
+  ],
+  [
+   "6957074593219251760608960101283708711892008557897337713430173510328411964571",
+   "21673833055087220750009279957462375662312260098732685145862504142183400549467",
+   "1"
+  ],
+  [
+   "20795071270535109448604057031148356571036039566776607847840379441839742201050",
+   "21654952744643117202636583766828639581880877547772465264383291983528268115687",
+   "1"
+  ],
+  [
+   "19143058772755719660075704757531991493801758701561469885274062297246796623789",
+   "3996020163280925980543600106196205910576345230982361007978823537163123181007",
+   "1"
+  ]
+ ]
+}

rln/resources/tree_height_20/verification_key.json

@@ -0,0 +1,119 @@
+{
+ "protocol": "groth16",
+ "curve": "bn128",
+ "nPublic": 6,
+ "vk_alpha_1": [
+  "20124996762962216725442980738609010303800849578410091356605067053491763969391",
+  "9118593021526896828671519912099489027245924097793322973632351264852174143923",
+  "1"
+ ],
+ "vk_beta_2": [
+  [
+   "4693952934005375501364248788849686435240706020501681709396105298107971354382",
+   "14346958885444710485362620645446987998958218205939139994511461437152241966681"
+  ],
+  [
+   "16851772916911573982706166384196538392731905827088356034885868448550849804972",
+   "823612331030938060799959717749043047845343400798220427319188951998582076532"
+  ],
+  [
+   "1",
+   "0"
+  ]
+ ],
+ "vk_gamma_2": [
+  [
+   "10857046999023057135944570762232829481370756359578518086990519993285655852781",
+   "11559732032986387107991004021392285783925812861821192530917403151452391805634"
+  ],
+  [
+   "8495653923123431417604973247489272438418190587263600148770280649306958101930",
+   "4082367875863433681332203403145435568316851327593401208105741076214120093531"
+  ],
+  [
+   "1",
+   "0"
+  ]
+ ],
+ "vk_delta_2": [
+  [
+   "8353516066399360694538747105302262515182301251524941126222712285088022964076",
+   "9329524012539638256356482961742014315122377605267454801030953882967973561832"
+  ],
+  [
+   "16805391589556134376869247619848130874761233086443465978238468412168162326401",
+   "10111259694977636294287802909665108497237922060047080343914303287629927847739"
+  ],
+  [
+   "1",
+   "0"
+  ]
+ ],
+ "vk_alphabeta_12": [
+  [
+   [
+    "12608968655665301215455851857466367636344427685631271961542642719683786103711",
+    "9849575605876329747382930567422916152871921500826003490242628251047652318086"
+   ],
+   [
+    "6322029441245076030714726551623552073612922718416871603535535085523083939021",
+    "8700115492541474338049149013125102281865518624059015445617546140629435818912"
+   ],
+   [
+    "10674973475340072635573101639867487770811074181475255667220644196793546640210",
+    "2926286967251299230490668407790788696102889214647256022788211245826267484824"
+   ]
+  ],
+  [
+   [
+    "9660441540778523475944706619139394922744328902833875392144658911530830074820",
+    "19548113127774514328631808547691096362144426239827206966690021428110281506546"
+   ],
+   [
+    "1870837942477655969123169532603615788122896469891695773961478956740992497097",
+    "12536105729661705698805725105036536744930776470051238187456307227425796690780"
+   ],
+   [
+    "21811903352654147452884857281720047789720483752548991551595462057142824037334",
+    "19021616763967199151052893283384285352200445499680068407023236283004353578353"
+   ]
+  ]
+ ],
+ "IC": [
+  [
+   "11992897507809711711025355300535923222599547639134311050809253678876341466909",
+   "17181525095924075896332561978747020491074338784673526378866503154966799128110",
+   "1"
+  ],
+  [
+   "17018665030246167677911144513385572506766200776123272044534328594850561667818",
+   "18601114175490465275436712413925513066546725461375425769709566180981674884464",
+   "1"
+  ],
+  [
+   "18799470100699658367834559797874857804183288553462108031963980039244731716542",
+   "13064227487174191981628537974951887429496059857753101852163607049188825592007",
+   "1"
+  ],
+  [
+   "17432501889058124609368103715904104425610382063762621017593209214189134571156",
+   "13406815149699834788256141097399354592751313348962590382887503595131085938635",
+   "1"
+  ],
+  [
+   "10320964835612716439094703312987075811498239445882526576970512041988148264481",
+   "9024164961646353611176283204118089412001502110138072989569118393359029324867",
+   "1"
+  ],
+  [
+   "718355081067365548229685160476620267257521491773976402837645005858953849298",
+   "14635482993933988261008156660773180150752190597753512086153001683711587601974",
+   "1"
+  ],
+  [
+   "11777720285956632126519898515392071627539405001940313098390150593689568177535",
+   "8483603647274280691250972408211651407952870456587066148445913156086740744515",
+   "1"
+  ]
+ ]
+}

rln/src/circuit.rs

@@ -4,63 +4,41 @@ use ark_bn254::{
     Bn254, Fq as ArkFq, Fq2 as ArkFq2, Fr as ArkFr, G1Affine as ArkG1Affine,
     G1Projective as ArkG1Projective, G2Affine as ArkG2Affine, G2Projective as ArkG2Projective,
 };
+use ark_circom::read_zkey;
 use ark_groth16::{ProvingKey, VerifyingKey};
 use ark_relations::r1cs::ConstraintMatrices;
-use ark_serialize::CanonicalDeserialize;
 use cfg_if::cfg_if;
 use color_eyre::{Report, Result};
+use num_bigint::BigUint;
+use serde_json::Value;
+use std::io::Cursor;
+use std::str::FromStr;
 
-#[cfg(not(target_arch = "wasm32"))]
-use {
-    ark_circom::WitnessCalculator,
-    lazy_static::lazy_static,
-    std::sync::{Arc, Mutex},
-    wasmer::{Module, Store},
-};
-
-#[cfg(feature = "arkzkey")]
-use {
-    ark_zkey::{read_arkzkey_from_bytes, SerializableConstraintMatrices, SerializableProvingKey},
-    color_eyre::eyre::WrapErr,
-};
-
-#[cfg(not(feature = "arkzkey"))]
-use {ark_circom::read_zkey, std::io::Cursor};
-
-#[cfg(feature = "arkzkey")]
-pub const ARKZKEY_BYTES: &[u8] = include_bytes!("../resources/tree_height_20/rln_final.arkzkey");
-#[cfg(feature = "arkzkey")]
-pub const ARKZKEY_BYTES_UNCOMPR: &[u8] =
-    include_bytes!("../resources/tree_height_20/rln_final_uncompr.arkzkey");
-
-pub const ZKEY_BYTES: &[u8] = include_bytes!("../resources/tree_height_20/rln_final.zkey");
-pub const VK_BYTES: &[u8] = include_bytes!("../resources/tree_height_20/verification_key.arkvkey");
-const WASM_BYTES: &[u8] = include_bytes!("../resources/tree_height_20/rln.wasm");
-
-#[cfg(not(target_arch = "wasm32"))]
-lazy_static! {
-    #[cfg(not(target_arch = "wasm32"))]
-    static ref ZKEY: (ProvingKey<Curve>, ConstraintMatrices<Fr>) = {
-        cfg_if! {
-                if #[cfg(feature = "arkzkey")] {
-                    read_arkzkey_from_bytes_uncompressed(ARKZKEY_BYTES_UNCOMPR).expect("Failed to read arkzkey")
-                } else {
-                    let mut reader = Cursor::new(ZKEY_BYTES);
-                    read_zkey(&mut reader).expect("Failed to read zkey")
-                }
-        }
-    };
-
-    #[cfg(not(target_arch = "wasm32"))]
-    static ref VK: VerifyingKey<Curve> = vk_from_ark_serialized(VK_BYTES).expect("Failed to read vk");
-
-    #[cfg(not(target_arch = "wasm32"))]
-    static ref WITNESS_CALCULATOR: Arc<Mutex<WitnessCalculator>> = {
-        circom_from_raw(WASM_BYTES).expect("Failed to create witness calculator")
-    };
+cfg_if! {
+    if #[cfg(not(target_arch = "wasm32"))] {
+        use ark_circom::{WitnessCalculator};
+        use once_cell::sync::OnceCell;
+        use std::sync::Mutex;
+        use wasmer::{Module, Store};
+        use include_dir::{include_dir, Dir};
+        use std::path::Path;
+    }
 }
 
-pub const TEST_TREE_HEIGHT: usize = 20;
+const ZKEY_FILENAME: &str = "rln_final.zkey";
+const VK_FILENAME: &str = "verification_key.json";
+const WASM_FILENAME: &str = "rln.wasm";
+
+// These parameters are used for tests
+// Note that the circuit and keys in TEST_RESOURCES_FOLDER are compiled for Merkle trees of height 15, 19 and 20
+// Changing these parameters to other values than these defaults will cause zkSNARK proof verification to fail
+pub const TEST_PARAMETERS_INDEX: usize = 2;
+pub const TEST_TREE_HEIGHT: usize = [15, 19, 20][TEST_PARAMETERS_INDEX];
+pub const TEST_RESOURCES_FOLDER: &str =
+    ["tree_height_15", "tree_height_19", "tree_height_20"][TEST_PARAMETERS_INDEX];
+
+#[cfg(not(target_arch = "wasm32"))]
+static RESOURCES_DIR: Dir<'_> = include_dir!("$CARGO_MANIFEST_DIR/resources");
 
 // The following types define the pairing friendly elliptic curve, the underlying finite fields and groups default to this module
 // Note that proofs are serialized assuming Fr to be 4x8 = 32 bytes in size. Hence, changing to a curve with different encoding will make proof verification to fail
@@ -74,152 +52,217 @@ pub type G2Affine = ArkG2Affine;
 pub type G2Projective = ArkG2Projective;
 
 // Loads the proving key using a bytes vector
-pub fn zkey_from_raw(zkey_data: &[u8]) -> Result<(ProvingKey<Curve>, ConstraintMatrices<Fr>)> {
-    if zkey_data.is_empty() {
-        return Err(Report::msg("No proving key found!"));
+pub fn zkey_from_raw(zkey_data: &Vec<u8>) -> Result<(ProvingKey<Curve>, ConstraintMatrices<Fr>)> {
+    if !zkey_data.is_empty() {
+        let mut c = Cursor::new(zkey_data);
+        let proving_key_and_matrices = read_zkey(&mut c)?;
+        Ok(proving_key_and_matrices)
+    } else {
+        Err(Report::msg("No proving key found!"))
     }
-
-    let proving_key_and_matrices = match () {
-        #[cfg(feature = "arkzkey")]
-        () => read_arkzkey_from_bytes(zkey_data)?,
-        #[cfg(not(feature = "arkzkey"))]
-        () => {
-            let mut reader = Cursor::new(zkey_data);
-            read_zkey(&mut reader)?
-        }
-    };
-
-    Ok(proving_key_and_matrices)
 }
 
 // Loads the proving key
 #[cfg(not(target_arch = "wasm32"))]
-pub fn zkey_from_folder() -> &'static (ProvingKey<Curve>, ConstraintMatrices<Fr>) {
-    &ZKEY
+pub fn zkey_from_folder(
+    resources_folder: &str,
+) -> Result<(ProvingKey<Curve>, ConstraintMatrices<Fr>)> {
+    let zkey = RESOURCES_DIR.get_file(Path::new(resources_folder).join(ZKEY_FILENAME));
+    if let Some(zkey) = zkey {
+        let mut c = Cursor::new(zkey.contents());
+        let proving_key_and_matrices = read_zkey(&mut c)?;
+        Ok(proving_key_and_matrices)
+    } else {
+        Err(Report::msg("No proving key found!"))
+    }
 }
 
 // Loads the verification key from a bytes vector
-pub fn vk_from_raw(vk_data: &[u8], zkey_data: &[u8]) -> Result<VerifyingKey<Curve>> {
+pub fn vk_from_raw(vk_data: &Vec<u8>, zkey_data: &Vec<u8>) -> Result<VerifyingKey<Curve>> {
+    let verifying_key: VerifyingKey<Curve>;
+
     if !vk_data.is_empty() {
-        return vk_from_ark_serialized(vk_data);
-    }
-
-    if !zkey_data.is_empty() {
+        verifying_key = vk_from_vector(vk_data)?;
+        Ok(verifying_key)
+    } else if !zkey_data.is_empty() {
         let (proving_key, _matrices) = zkey_from_raw(zkey_data)?;
-        return Ok(proving_key.vk);
+        verifying_key = proving_key.vk;
+        Ok(verifying_key)
+    } else {
+        Err(Report::msg("No proving/verification key found!"))
     }
-
-    Err(Report::msg("No proving/verification key found!"))
 }
 
 // Loads the verification key
 #[cfg(not(target_arch = "wasm32"))]
-pub fn vk_from_folder() -> &'static VerifyingKey<Curve> {
-    &VK
+pub fn vk_from_folder(resources_folder: &str) -> Result<VerifyingKey<Curve>> {
+    let vk = RESOURCES_DIR.get_file(Path::new(resources_folder).join(VK_FILENAME));
+    let zkey = RESOURCES_DIR.get_file(Path::new(resources_folder).join(ZKEY_FILENAME));
+
+    let verifying_key: VerifyingKey<Curve>;
+    if let Some(vk) = vk {
+        verifying_key = vk_from_json(vk.contents_utf8().ok_or(Report::msg(
+            "Could not read verification key from JSON file!",
+        ))?)?;
+        Ok(verifying_key)
+    } else if let Some(_zkey) = zkey {
+        let (proving_key, _matrices) = zkey_from_folder(resources_folder)?;
+        verifying_key = proving_key.vk;
+        Ok(verifying_key)
+    } else {
+        Err(Report::msg("No proving/verification key found!"))
+    }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
+static WITNESS_CALCULATOR: OnceCell<Mutex<WitnessCalculator>> = OnceCell::new();
+
 // Initializes the witness calculator using a bytes vector
 #[cfg(not(target_arch = "wasm32"))]
-pub fn circom_from_raw(wasm_buffer: &[u8]) -> Result<Arc<Mutex<WitnessCalculator>>> {
-    let module = Module::new(&Store::default(), wasm_buffer)?;
-    let result = WitnessCalculator::from_module(module)?;
-    Ok(Arc::new(Mutex::new(result)))
+pub fn circom_from_raw(wasm_buffer: Vec<u8>) -> Result<&'static Mutex<WitnessCalculator>> {
+    WITNESS_CALCULATOR.get_or_try_init(|| {
+        let store = Store::default();
+        let module = Module::new(&store, wasm_buffer)?;
+        let result = WitnessCalculator::from_module(module)?;
+        Ok::<Mutex<WitnessCalculator>, Report>(Mutex::new(result))
+    })
 }
 
 // Initializes the witness calculator
 #[cfg(not(target_arch = "wasm32"))]
-pub fn circom_from_folder() -> &'static Arc<Mutex<WitnessCalculator>> {
-    &WITNESS_CALCULATOR
+pub fn circom_from_folder(resources_folder: &str) -> Result<&'static Mutex<WitnessCalculator>> {
+    // We read the wasm file
+    let wasm = RESOURCES_DIR.get_file(Path::new(resources_folder).join(WASM_FILENAME));
+
+    if let Some(wasm) = wasm {
+        let wasm_buffer = wasm.contents();
+        circom_from_raw(wasm_buffer.to_vec())
+    } else {
+        Err(Report::msg("No wasm file found!"))
+    }
 }
 
-// Computes the verification key from a bytes vector containing pre-processed ark-serialized verification key
-// uncompressed, unchecked
-pub fn vk_from_ark_serialized(data: &[u8]) -> Result<VerifyingKey<Curve>> {
-    let vk = VerifyingKey::<Curve>::deserialize_uncompressed_unchecked(data)?;
-    Ok(vk)
+// The following function implementations are taken/adapted from https://github.com/gakonst/ark-circom/blob/1732e15d6313fe176b0b1abb858ac9e095d0dbd7/src/zkey.rs
+
+// Utilities to convert a json verification key in a groth16::VerificationKey
+fn fq_from_str(s: &str) -> Result<Fq> {
+    Ok(Fq::try_from(BigUint::from_str(s)?)?)
+}
+
+// Extracts the element in G1 corresponding to its JSON serialization
+fn json_to_g1(json: &Value, key: &str) -> Result<G1Affine> {
+    let els: Vec<String> = json
+        .get(key)
+        .ok_or(Report::msg("no json value"))?
+        .as_array()
+        .ok_or(Report::msg("value not an array"))?
+        .iter()
+        .map(|i| i.as_str().ok_or(Report::msg("element is not a string")))
+        .map(|x| x.map(|v| v.to_owned()))
+        .collect::<Result<Vec<String>>>()?;
+
+    Ok(G1Affine::from(G1Projective::new(
+        fq_from_str(&els[0])?,
+        fq_from_str(&els[1])?,
+        fq_from_str(&els[2])?,
+    )))
+}
+
+// Extracts the vector of G1 elements corresponding to its JSON serialization
+fn json_to_g1_vec(json: &Value, key: &str) -> Result<Vec<G1Affine>> {
+    let els: Vec<Vec<String>> = json
+        .get(key)
+        .ok_or(Report::msg("no json value"))?
+        .as_array()
+        .ok_or(Report::msg("value not an array"))?
+        .iter()
+        .map(|i| {
+            i.as_array()
+                .ok_or(Report::msg("element is not an array"))
+                .and_then(|array| {
+                    array
+                        .iter()
+                        .map(|x| x.as_str().ok_or(Report::msg("element is not a string")))
+                        .map(|x| x.map(|v| v.to_owned()))
+                        .collect::<Result<Vec<String>>>()
+                })
+        })
+        .collect::<Result<Vec<Vec<String>>>>()?;
+
+    let mut res = vec![];
+    for coords in els {
+        res.push(G1Affine::from(G1Projective::new(
+            fq_from_str(&coords[0])?,
+            fq_from_str(&coords[1])?,
+            fq_from_str(&coords[2])?,
+        )))
+    }
+
+    Ok(res)
+}
+
+// Extracts the element in G2 corresponding to its JSON serialization
+fn json_to_g2(json: &Value, key: &str) -> Result<G2Affine> {
+    let els: Vec<Vec<String>> = json
+        .get(key)
+        .ok_or(Report::msg("no json value"))?
+        .as_array()
+        .ok_or(Report::msg("value not an array"))?
+        .iter()
+        .map(|i| {
+            i.as_array()
+                .ok_or(Report::msg("element is not an array"))
+                .and_then(|array| {
+                    array
+                        .iter()
+                        .map(|x| x.as_str().ok_or(Report::msg("element is not a string")))
+                        .map(|x| x.map(|v| v.to_owned()))
+                        .collect::<Result<Vec<String>>>()
+                })
+        })
+        .collect::<Result<Vec<Vec<String>>>>()?;
+
+    let x = Fq2::new(fq_from_str(&els[0][0])?, fq_from_str(&els[0][1])?);
+    let y = Fq2::new(fq_from_str(&els[1][0])?, fq_from_str(&els[1][1])?);
+    let z = Fq2::new(fq_from_str(&els[2][0])?, fq_from_str(&els[2][1])?);
+    Ok(G2Affine::from(G2Projective::new(x, y, z)))
+}
+
+// Converts JSON to a VerifyingKey
+fn to_verifying_key(json: serde_json::Value) -> Result<VerifyingKey<Curve>> {
+    Ok(VerifyingKey {
+        alpha_g1: json_to_g1(&json, "vk_alpha_1")?,
+        beta_g2: json_to_g2(&json, "vk_beta_2")?,
+        gamma_g2: json_to_g2(&json, "vk_gamma_2")?,
+        delta_g2: json_to_g2(&json, "vk_delta_2")?,
+        gamma_abc_g1: json_to_g1_vec(&json, "IC")?,
+    })
+}
+
+// Computes the verification key from its JSON serialization
+fn vk_from_json(vk: &str) -> Result<VerifyingKey<Curve>> {
+    let json: Value = serde_json::from_str(vk)?;
+    to_verifying_key(json)
+}
+
+// Computes the verification key from a bytes vector containing its JSON serialization
+fn vk_from_vector(vk: &[u8]) -> Result<VerifyingKey<Curve>> {
+    let json = String::from_utf8(vk.to_vec())?;
+    let json: Value = serde_json::from_str(&json)?;
+
+    to_verifying_key(json)
 }
 
 // Checks verification key to be correct with respect to proving key
 #[cfg(not(target_arch = "wasm32"))]
-pub fn check_vk_from_zkey(verifying_key: VerifyingKey<Curve>) -> Result<()> {
-    let (proving_key, _matrices) = zkey_from_folder();
+pub fn check_vk_from_zkey(
+    resources_folder: &str,
+    verifying_key: VerifyingKey<Curve>,
+) -> Result<()> {
+    let (proving_key, _matrices) = zkey_from_folder(resources_folder)?;
     if proving_key.vk == verifying_key {
         Ok(())
     } else {
         Err(Report::msg("verifying_keys are not equal"))
     }
 }
-
-////////////////////////////////////////////////////////
-// Functions from [arkz-key](https://github.com/zkmopro/ark-zkey/blob/main/src/lib.rs#L106)
-// without print and allow to choose between compressed and uncompressed arkzkey
-////////////////////////////////////////////////////////
-#[cfg(feature = "arkzkey")]
-pub fn read_arkzkey_from_bytes_uncompressed(
-    arkzkey_data: &[u8],
-) -> Result<(ProvingKey<Curve>, ConstraintMatrices<Fr>)> {
-    if arkzkey_data.is_empty() {
-        return Err(Report::msg("No proving key found!"));
-    }
-
-    let mut cursor = std::io::Cursor::new(arkzkey_data);
-
-    let serialized_proving_key =
-        SerializableProvingKey::deserialize_uncompressed_unchecked(&mut cursor)
-            .wrap_err("Failed to deserialize proving key")?;
-
-    let serialized_constraint_matrices =
-        SerializableConstraintMatrices::deserialize_uncompressed_unchecked(&mut cursor)
-            .wrap_err("Failed to deserialize constraint matrices")?;
-
-    // Get on right form for API
-    let proving_key: ProvingKey<Bn254> = serialized_proving_key.0;
-    let constraint_matrices: ConstraintMatrices<ark_bn254::Fr> = ConstraintMatrices {
-        num_instance_variables: serialized_constraint_matrices.num_instance_variables,
-        num_witness_variables: serialized_constraint_matrices.num_witness_variables,
-        num_constraints: serialized_constraint_matrices.num_constraints,
-        a_num_non_zero: serialized_constraint_matrices.a_num_non_zero,
-        b_num_non_zero: serialized_constraint_matrices.b_num_non_zero,
-        c_num_non_zero: serialized_constraint_matrices.c_num_non_zero,
-        a: serialized_constraint_matrices.a.data,
-        b: serialized_constraint_matrices.b.data,
-        c: serialized_constraint_matrices.c.data,
-    };
-
-    Ok((proving_key, constraint_matrices))
-}
-
-#[cfg(feature = "arkzkey")]
-pub fn read_arkzkey_from_bytes_compressed(
-    arkzkey_data: &[u8],
-) -> Result<(ProvingKey<Curve>, ConstraintMatrices<Fr>)> {
-    if arkzkey_data.is_empty() {
-        return Err(Report::msg("No proving key found!"));
-    }
-
-    let mut cursor = std::io::Cursor::new(arkzkey_data);
-
-    let serialized_proving_key =
-        SerializableProvingKey::deserialize_compressed_unchecked(&mut cursor)
-            .wrap_err("Failed to deserialize proving key")?;
-
-    let serialized_constraint_matrices =
-        SerializableConstraintMatrices::deserialize_compressed_unchecked(&mut cursor)
-            .wrap_err("Failed to deserialize constraint matrices")?;
-
-    // Get on right form for API
-    let proving_key: ProvingKey<Bn254> = serialized_proving_key.0;
-    let constraint_matrices: ConstraintMatrices<ark_bn254::Fr> = ConstraintMatrices {
-        num_instance_variables: serialized_constraint_matrices.num_instance_variables,
-        num_witness_variables: serialized_constraint_matrices.num_witness_variables,
-        num_constraints: serialized_constraint_matrices.num_constraints,
-        a_num_non_zero: serialized_constraint_matrices.a_num_non_zero,
-        b_num_non_zero: serialized_constraint_matrices.b_num_non_zero,
-        c_num_non_zero: serialized_constraint_matrices.c_num_non_zero,
-        a: serialized_constraint_matrices.a.data,
-        b: serialized_constraint_matrices.b.data,
-        c: serialized_constraint_matrices.c.data,
-    };
-
-    Ok((proving_key, constraint_matrices))
-}

rln/src/ffi.rs

@@ -143,24 +143,24 @@ impl ProcessArg for *const Buffer {
     }
 }
 
-impl ProcessArg for *const RLN {
-    type ReturnType = &'static RLN;
+impl<'a> ProcessArg for *const RLN<'a> {
+    type ReturnType = &'a RLN<'a>;
     fn process(self) -> Self::ReturnType {
         unsafe { &*self }
     }
 }
 
-impl ProcessArg for *mut RLN {
-    type ReturnType = &'static mut RLN;
+impl<'a> ProcessArg for *mut RLN<'a> {
+    type ReturnType = &'a mut RLN<'a>;
     fn process(self) -> Self::ReturnType {
         unsafe { &mut *self }
     }
 }
 
-///// Buffer struct is taken from
-///// <https://github.com/celo-org/celo-threshold-bls-rs/blob/master/crates/threshold-bls-ffi/src/ffi.rs>
-/////
-///// Also heavily inspired by <https://github.com/kilic/rln/blob/master/src/ffi.rs>
+/// Buffer struct is taken from
+/// <https://github.com/celo-org/celo-threshold-bls-rs/blob/master/crates/threshold-bls-ffi/src/ffi.rs>
+///
+/// Also heavily inspired by <https://github.com/kilic/rln/blob/master/src/ffi.rs>
 
 #[repr(C)]
 #[derive(Clone, Debug, PartialEq)]
@@ -192,7 +192,6 @@ impl<'a> From<&Buffer> for &'a [u8] {
 ////////////////////////////////////////////////////////
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
-#[cfg(not(feature = "stateless"))]
 #[no_mangle]
 pub extern "C" fn new(tree_height: usize, input_buffer: *const Buffer, ctx: *mut *mut RLN) -> bool {
     match RLN::new(tree_height, input_buffer.process()) {
@@ -208,23 +207,6 @@ pub extern "C" fn new(tree_height: usize, input_buffer: *const Buffer, ctx: *mut
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
-#[cfg(feature = "stateless")]
-#[no_mangle]
-pub extern "C" fn new(ctx: *mut *mut RLN) -> bool {
-    match RLN::new() {
-        Ok(rln) => {
-            unsafe { *ctx = Box::into_raw(Box::new(rln)) };
-            true
-        }
-        Err(err) => {
-            eprintln!("could not instantiate rln: {err}");
-            false
-        }
-    }
-}
-
-#[allow(clippy::not_unsafe_ptr_arg_deref)]
-#[cfg(not(feature = "stateless"))]
 #[no_mangle]
 pub extern "C" fn new_with_params(
     tree_height: usize,
@@ -252,79 +234,47 @@ pub extern "C" fn new_with_params(
     }
 }
 
-#[allow(clippy::not_unsafe_ptr_arg_deref)]
-#[cfg(feature = "stateless")]
-#[no_mangle]
-pub extern "C" fn new_with_params(
-    circom_buffer: *const Buffer,
-    zkey_buffer: *const Buffer,
-    vk_buffer: *const Buffer,
-    ctx: *mut *mut RLN,
-) -> bool {
-    match RLN::new_with_params(
-        circom_buffer.process().to_vec(),
-        zkey_buffer.process().to_vec(),
-        vk_buffer.process().to_vec(),
-    ) {
-        Ok(rln) => {
-            unsafe { *ctx = Box::into_raw(Box::new(rln)) };
-            true
-        }
-        Err(err) => {
-            eprintln!("could not instantiate rln: {err}");
-            false
-        }
-    }
-}
-
 ////////////////////////////////////////////////////////
 // Merkle tree APIs
 ////////////////////////////////////////////////////////
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn set_tree(ctx: *mut RLN, tree_height: usize) -> bool {
     call!(ctx, set_tree, tree_height)
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn delete_leaf(ctx: *mut RLN, index: usize) -> bool {
     call!(ctx, delete_leaf, index)
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn set_leaf(ctx: *mut RLN, index: usize, input_buffer: *const Buffer) -> bool {
     call!(ctx, set_leaf, index, input_buffer)
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn get_leaf(ctx: *mut RLN, index: usize, output_buffer: *mut Buffer) -> bool {
     call_with_output_arg!(ctx, get_leaf, output_buffer, index)
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn leaves_set(ctx: *mut RLN) -> usize {
     ctx.process().leaves_set()
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn set_next_leaf(ctx: *mut RLN, input_buffer: *const Buffer) -> bool {
     call!(ctx, set_next_leaf, input_buffer)
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn set_leaves_from(
     ctx: *mut RLN,
     index: usize,
@@ -335,14 +285,12 @@ pub extern "C" fn set_leaves_from(
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn init_tree_with_leaves(ctx: *mut RLN, input_buffer: *const Buffer) -> bool {
     call!(ctx, init_tree_with_leaves, input_buffer)
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn atomic_operation(
     ctx: *mut RLN,
     index: usize,
@@ -354,7 +302,6 @@ pub extern "C" fn atomic_operation(
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn seq_atomic_operation(
     ctx: *mut RLN,
     leaves_buffer: *const Buffer,
@@ -371,14 +318,12 @@ pub extern "C" fn seq_atomic_operation(
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn get_root(ctx: *const RLN, output_buffer: *mut Buffer) -> bool {
     call_with_output_arg!(ctx, get_root, output_buffer)
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn get_proof(ctx: *const RLN, index: usize, output_buffer: *mut Buffer) -> bool {
     call_with_output_arg!(ctx, get_proof, output_buffer, index)
 }
@@ -408,7 +353,6 @@ pub extern "C" fn verify(
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn generate_rln_proof(
     ctx: *mut RLN,
     input_buffer: *const Buffer,
@@ -434,7 +378,6 @@ pub extern "C" fn generate_rln_proof_with_witness(
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn verify_rln_proof(
     ctx: *const RLN,
     proof_buffer: *const Buffer,
@@ -518,21 +461,18 @@ pub extern "C" fn recover_id_secret(
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn set_metadata(ctx: *mut RLN, input_buffer: *const Buffer) -> bool {
     call!(ctx, set_metadata, input_buffer)
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn get_metadata(ctx: *const RLN, output_buffer: *mut Buffer) -> bool {
     call_with_output_arg!(ctx, get_metadata, output_buffer)
 }
 
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 #[no_mangle]
-#[cfg(not(feature = "stateless"))]
 pub extern "C" fn flush(ctx: *mut RLN) -> bool {
     call!(ctx, flush)
 }

rln/src/lib.rs

@@ -7,8 +7,6 @@ pub mod pm_tree_adapter;
 pub mod poseidon_tree;
 pub mod protocol;
 pub mod public;
-#[cfg(test)]
-pub mod public_api_tests;
 pub mod utils;
 
 #[cfg(not(target_arch = "wasm32"))]

rln/src/pm_tree_adapter.rs

@@ -5,7 +5,6 @@ use std::str::FromStr;
 use color_eyre::{Report, Result};
 use serde_json::Value;
 
-use utils::pmtree::tree::Key;
 use utils::pmtree::{Database, Hasher};
 use utils::*;
 
@@ -17,9 +16,6 @@ const METADATA_KEY: [u8; 8] = *b"metadata";
 
 pub struct PmTree {
     tree: pmtree::MerkleTree<SledDB, PoseidonHash>,
-    /// The indices of leaves which are set into zero upto next_index.
-    /// Set to 0 if the leaf is empty and set to 1 in otherwise.
-    cached_leaves_indices: Vec<u8>,
     // metadata that an application may use to store additional information
     metadata: Vec<u8>,
 }
@@ -147,7 +143,6 @@ impl ZerokitMerkleTree for PmTree {
 
         Ok(PmTree {
             tree,
-            cached_leaves_indices: vec![0; 1 << depth],
             metadata: Vec::new(),
         })
     }
@@ -160,7 +155,7 @@ impl ZerokitMerkleTree for PmTree {
         self.tree.capacity()
     }
 
-    fn leaves_set(&self) -> usize {
+    fn leaves_set(&mut self) -> usize {
         self.tree.leaves_set()
     }
 
@@ -175,9 +170,7 @@ impl ZerokitMerkleTree for PmTree {
     fn set(&mut self, index: usize, leaf: FrOf<Self::Hasher>) -> Result<()> {
         self.tree
             .set(index, leaf)
-            .map_err(|e| Report::msg(e.to_string()))?;
-        self.cached_leaves_indices[index] = 1;
-        Ok(())
+            .map_err(|e| Report::msg(e.to_string()))
     }
 
     fn set_range<I: IntoIterator<Item = FrOf<Self::Hasher>>>(
@@ -185,51 +178,15 @@ impl ZerokitMerkleTree for PmTree {
         start: usize,
         values: I,
     ) -> Result<()> {
-        let v = values.into_iter().collect::<Vec<_>>();
         self.tree
-            .set_range(start, v.clone().into_iter())
-            .map_err(|e| Report::msg(e.to_string()))?;
-        for i in start..v.len() {
-            self.cached_leaves_indices[i] = 1
-        }
-        Ok(())
+            .set_range(start, values)
+            .map_err(|e| Report::msg(e.to_string()))
     }
 
     fn get(&self, index: usize) -> Result<FrOf<Self::Hasher>> {
         self.tree.get(index).map_err(|e| Report::msg(e.to_string()))
     }
 
-    fn get_subtree_root(&self, n: usize, index: usize) -> Result<FrOf<Self::Hasher>> {
-        if n > self.depth() {
-            return Err(Report::msg("level exceeds depth size"));
-        }
-        if index >= self.capacity() {
-            return Err(Report::msg("index exceeds set size"));
-        }
-        if n == 0 {
-            Ok(self.root())
-        } else if n == self.depth() {
-            self.get(index)
-        } else {
-            let node = self
-                .tree
-                .get_elem(Key::new(n, index >> (self.depth() - n)))
-                .unwrap();
-            Ok(node)
-        }
-    }
-
-    fn get_empty_leaves_indices(&self) -> Vec<usize> {
-        let next_idx = self.leaves_set();
-        self.cached_leaves_indices
-            .iter()
-            .take(next_idx)
-            .enumerate()
-            .filter(|&(_, &v)| v == 0u8)
-            .map(|(idx, _)| idx)
-            .collect()
-    }
-
     fn override_range<I: IntoIterator<Item = FrOf<Self::Hasher>>, J: IntoIterator<Item = usize>>(
         &mut self,
         start: usize,
@@ -244,7 +201,7 @@ impl ZerokitMerkleTree for PmTree {
             (0, 0) => Err(Report::msg("no leaves or indices to be removed")),
             (1, 0) => self.set(start, leaves[0]),
             (0, 1) => self.delete(indices[0]),
-            (_, 0) => self.set_range(start, leaves),
+            (_, 0) => self.set_range_with_leaves(start, leaves),
             (0, _) => self.remove_indices(&indices),
             (_, _) => self.remove_indices_and_set_leaves(start, leaves, &indices),
         }
@@ -259,9 +216,7 @@ impl ZerokitMerkleTree for PmTree {
     fn delete(&mut self, index: usize) -> Result<()> {
         self.tree
             .delete(index)
-            .map_err(|e| Report::msg(e.to_string()))?;
-        self.cached_leaves_indices[index] = 0;
-        Ok(())
+            .map_err(|e| Report::msg(e.to_string()))
     }
 
     fn proof(&self, index: usize) -> Result<Self::Proof> {
@@ -306,6 +261,12 @@ type PmTreeHasher = <PmTree as ZerokitMerkleTree>::Hasher;
 type FrOfPmTreeHasher = FrOf<PmTreeHasher>;
 
 impl PmTree {
+    fn set_range_with_leaves(&mut self, start: usize, leaves: Vec<FrOfPmTreeHasher>) -> Result<()> {
+        self.tree
+            .set_range(start, leaves)
+            .map_err(|e| Report::msg(e.to_string()))
+    }
+
     fn remove_indices(&mut self, indices: &[usize]) -> Result<()> {
         let start = indices[0];
         let end = indices.last().unwrap() + 1;
@@ -314,12 +275,7 @@ impl PmTree {
 
         self.tree
             .set_range(start, new_leaves)
-            .map_err(|e| Report::msg(e.to_string()))?;
-
-        for i in start..end {
-            self.cached_leaves_indices[i] = 0
-        }
-        Ok(())
+            .map_err(|e| Report::msg(e.to_string()))
     }
 
     fn remove_indices_and_set_leaves(
@@ -345,17 +301,8 @@ impl PmTree {
         }
 
         self.tree
-            .set_range(start, set_values)
-            .map_err(|e| Report::msg(e.to_string()))?;
-
-        for i in indices {
-            self.cached_leaves_indices[*i] = 0;
-        }
-
-        for i in start..(max_index - min_index) {
-            self.cached_leaves_indices[i] = 1
-        }
-        Ok(())
+            .set_range(min_index, set_values)
+            .map_err(|e| Report::msg(e.to_string()))
     }
 }
 

rln/src/protocol.rs

@@ -4,13 +4,11 @@ use ark_circom::{CircomReduction, WitnessCalculator};
 use ark_groth16::{prepare_verifying_key, Groth16, Proof as ArkProof, ProvingKey, VerifyingKey};
 use ark_relations::r1cs::ConstraintMatrices;
 use ark_relations::r1cs::SynthesisError;
-use ark_serialize::{CanonicalDeserialize, CanonicalSerialize};
 use ark_std::{rand::thread_rng, UniformRand};
 use color_eyre::{Report, Result};
 use num_bigint::BigInt;
 use rand::{Rng, SeedableRng};
 use rand_chacha::ChaCha20Rng;
-use serde::{Deserialize, Serialize};
 #[cfg(not(target_arch = "wasm32"))]
 use std::sync::Mutex;
 #[cfg(debug_assertions)]
@@ -31,21 +29,14 @@ use utils::{ZerokitMerkleProof, ZerokitMerkleTree};
 // RLN Witness data structure and utility functions
 ///////////////////////////////////////////////////////
 
-#[derive(Debug, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, PartialEq)]
 pub struct RLNWitnessInput {
-    #[serde(serialize_with = "ark_se", deserialize_with = "ark_de")]
     identity_secret: Fr,
-    #[serde(serialize_with = "ark_se", deserialize_with = "ark_de")]
-    user_message_limit: Fr,
-    #[serde(serialize_with = "ark_se", deserialize_with = "ark_de")]
-    message_id: Fr,
-    #[serde(serialize_with = "ark_se", deserialize_with = "ark_de")]
     path_elements: Vec<Fr>,
     identity_path_index: Vec<u8>,
-    #[serde(serialize_with = "ark_se", deserialize_with = "ark_de")]
     x: Fr,
-    #[serde(serialize_with = "ark_se", deserialize_with = "ark_de")]
-    external_nullifier: Fr,
+    epoch: Fr,
+    rln_identifier: Fr,
 }
 
 #[derive(Debug, PartialEq)]
@@ -56,7 +47,8 @@ pub struct RLNProofValues {
     pub root: Fr,
     // Public Inputs:
     pub x: Fr,
-    pub external_nullifier: Fr,
+    pub epoch: Fr,
+    pub rln_identifier: Fr,
 }
 
 pub fn serialize_field_element(element: Fr) -> Vec<u8> {
@@ -98,46 +90,25 @@ pub fn deserialize_identity_tuple(serialized: Vec<u8>) -> (Fr, Fr, Fr, Fr) {
     )
 }
 
-/// Serializes witness
-///
-/// # Errors
-///
-/// Returns an error if `rln_witness.message_id` is not within `rln_witness.user_message_limit`.
 pub fn serialize_witness(rln_witness: &RLNWitnessInput) -> Result<Vec<u8>> {
-    message_id_range_check(&rln_witness.message_id, &rln_witness.user_message_limit)?;
-
     let mut serialized: Vec<u8> = Vec::new();
 
     serialized.append(&mut fr_to_bytes_le(&rln_witness.identity_secret));
-    serialized.append(&mut fr_to_bytes_le(&rln_witness.user_message_limit));
-    serialized.append(&mut fr_to_bytes_le(&rln_witness.message_id));
     serialized.append(&mut vec_fr_to_bytes_le(&rln_witness.path_elements)?);
     serialized.append(&mut vec_u8_to_bytes_le(&rln_witness.identity_path_index)?);
     serialized.append(&mut fr_to_bytes_le(&rln_witness.x));
-    serialized.append(&mut fr_to_bytes_le(&rln_witness.external_nullifier));
+    serialized.append(&mut fr_to_bytes_le(&rln_witness.epoch));
+    serialized.append(&mut fr_to_bytes_le(&rln_witness.rln_identifier));
 
     Ok(serialized)
 }
 
-/// Deserializes witness
-///
-/// # Errors
-///
-/// Returns an error if `message_id` is not within `user_message_limit`.
 pub fn deserialize_witness(serialized: &[u8]) -> Result<(RLNWitnessInput, usize)> {
     let mut all_read: usize = 0;
 
     let (identity_secret, read) = bytes_le_to_fr(&serialized[all_read..]);
     all_read += read;
 
-    let (user_message_limit, read) = bytes_le_to_fr(&serialized[all_read..]);
-    all_read += read;
-
-    let (message_id, read) = bytes_le_to_fr(&serialized[all_read..]);
-    all_read += read;
-
-    message_id_range_check(&message_id, &user_message_limit)?;
-
     let (path_elements, read) = bytes_le_to_vec_fr(&serialized[all_read..])?;
     all_read += read;
 
@@ -147,9 +118,13 @@ pub fn deserialize_witness(serialized: &[u8]) -> Result<(RLNWitnessInput, usize)
     let (x, read) = bytes_le_to_fr(&serialized[all_read..]);
     all_read += read;
 
-    let (external_nullifier, read) = bytes_le_to_fr(&serialized[all_read..]);
+    let (epoch, read) = bytes_le_to_fr(&serialized[all_read..]);
     all_read += read;
 
+    let (rln_identifier, read) = bytes_le_to_fr(&serialized[all_read..]);
+    all_read += read;
+
+    // TODO: check rln_identifier against public::RLN_IDENTIFIER
     if serialized.len() != all_read {
         return Err(Report::msg("serialized length is not equal to all_read"));
     }
@@ -160,9 +135,8 @@ pub fn deserialize_witness(serialized: &[u8]) -> Result<(RLNWitnessInput, usize)
             path_elements,
             identity_path_index,
             x,
-            external_nullifier,
-            user_message_limit,
-            message_id,
+            epoch,
+            rln_identifier,
         },
         all_read,
     ))
@@ -170,7 +144,7 @@ pub fn deserialize_witness(serialized: &[u8]) -> Result<(RLNWitnessInput, usize)
 
 // This function deserializes input for kilic's rln generate_proof public API
 // https://github.com/kilic/rln/blob/7ac74183f8b69b399e3bc96c1ae8ab61c026dc43/src/public.rs#L148
-// input_data is [ identity_secret<32> | id_index<8> | user_message_limit<32> | message_id<32> | external_nullifier<32> | signal_len<8> | signal<var> ]
+// input_data is [ identity_secret<32> | id_index<8> | epoch<32> | signal_len<8> | signal<var> ]
 // return value is a rln witness populated according to this information
 pub fn proof_inputs_to_rln_witness(
     tree: &mut PoseidonTree,
@@ -186,13 +160,7 @@ pub fn proof_inputs_to_rln_witness(
     ))?;
     all_read += 8;
 
-    let (user_message_limit, read) = bytes_le_to_fr(&serialized[all_read..]);
-    all_read += read;
-
-    let (message_id, read) = bytes_le_to_fr(&serialized[all_read..]);
-    all_read += read;
-
-    let (external_nullifier, read) = bytes_le_to_fr(&serialized[all_read..]);
+    let (epoch, read) = bytes_le_to_fr(&serialized[all_read..]);
     all_read += read;
 
     let signal_len = usize::try_from(u64::from_le_bytes(
@@ -208,49 +176,83 @@ pub fn proof_inputs_to_rln_witness(
 
     let x = hash_to_field(&signal);
 
+    let rln_identifier = hash_to_field(RLN_IDENTIFIER);
+
     Ok((
         RLNWitnessInput {
             identity_secret,
             path_elements,
             identity_path_index,
-            user_message_limit,
-            message_id,
             x,
-            external_nullifier,
+            epoch,
+            rln_identifier,
         },
         all_read,
     ))
 }
 
-/// Creates `RLNWitnessInput` from it's fields.
-///
-/// # Errors
-///
-/// Returns an error if `message_id` is not within `user_message_limit`.
-pub fn rln_witness_from_values(
-    identity_secret: Fr,
-    merkle_proof: &MerkleProof,
-    x: Fr,
-    external_nullifier: Fr,
-    user_message_limit: Fr,
-    message_id: Fr,
-) -> Result<RLNWitnessInput> {
-    message_id_range_check(&message_id, &user_message_limit)?;
+pub fn rln_witness_from_json(input_json_str: &str) -> Result<RLNWitnessInput> {
+    let input_json: serde_json::Value =
+        serde_json::from_str(input_json_str).expect("JSON was not well-formatted");
 
-    let path_elements = merkle_proof.get_path_elements();
-    let identity_path_index = merkle_proof.get_path_index();
+    let identity_secret = str_to_fr(&input_json["identity_secret"].to_string(), 10)?;
+
+    let path_elements = input_json["path_elements"]
+        .as_array()
+        .ok_or(Report::msg("not an array"))?
+        .iter()
+        .map(|v| str_to_fr(&v.to_string(), 10))
+        .collect::<Result<_>>()?;
+
+    let identity_path_index_array = input_json["identity_path_index"]
+        .as_array()
+        .ok_or(Report::msg("not an arrray"))?;
+
+    let mut identity_path_index: Vec<u8> = vec![];
+
+    for v in identity_path_index_array {
+        identity_path_index.push(v.as_u64().ok_or(Report::msg("not a u64 value"))? as u8);
+    }
+
+    let x = str_to_fr(&input_json["x"].to_string(), 10)?;
+
+    let epoch = str_to_fr(&input_json["epoch"].to_string(), 16)?;
+
+    let rln_identifier = str_to_fr(&input_json["rln_identifier"].to_string(), 10)?;
+
+    // TODO: check rln_identifier against public::RLN_IDENTIFIER
 
     Ok(RLNWitnessInput {
         identity_secret,
         path_elements,
         identity_path_index,
         x,
-        external_nullifier,
-        user_message_limit,
-        message_id,
+        epoch,
+        rln_identifier,
     })
 }
 
+pub fn rln_witness_from_values(
+    identity_secret: Fr,
+    merkle_proof: &MerkleProof,
+    x: Fr,
+    epoch: Fr,
+    //rln_identifier: Fr,
+) -> RLNWitnessInput {
+    let path_elements = merkle_proof.get_path_elements();
+    let identity_path_index = merkle_proof.get_path_index();
+    let rln_identifier = hash_to_field(RLN_IDENTIFIER);
+
+    RLNWitnessInput {
+        identity_secret,
+        path_elements,
+        identity_path_index,
+        x,
+        epoch,
+        rln_identifier,
+    }
+}
+
 pub fn random_rln_witness(tree_height: usize) -> RLNWitnessInput {
     let mut rng = thread_rng();
 
@@ -267,26 +269,21 @@ pub fn random_rln_witness(tree_height: usize) -> RLNWitnessInput {
         identity_path_index.push(rng.gen_range(0..2) as u8);
     }
 
-    let user_message_limit = Fr::from(100);
-    let message_id = Fr::from(1);
-
     RLNWitnessInput {
         identity_secret,
         path_elements,
         identity_path_index,
         x,
-        external_nullifier: poseidon_hash(&[epoch, rln_identifier]),
-        user_message_limit,
-        message_id,
+        epoch,
+        rln_identifier,
     }
 }
 
-pub fn proof_values_from_witness(rln_witness: &RLNWitnessInput) -> Result<RLNProofValues> {
-    message_id_range_check(&rln_witness.message_id, &rln_witness.user_message_limit)?;
-
+pub fn proof_values_from_witness(rln_witness: &RLNWitnessInput) -> RLNProofValues {
     // y share
+    let external_nullifier = poseidon_hash(&[rln_witness.epoch, rln_witness.rln_identifier]);
     let a_0 = rln_witness.identity_secret;
-    let a_1 = poseidon_hash(&[a_0, rln_witness.external_nullifier, rln_witness.message_id]);
+    let a_1 = poseidon_hash(&[a_0, external_nullifier]);
     let y = a_0 + rln_witness.x * a_1;
 
     // Nullifier
@@ -295,28 +292,30 @@ pub fn proof_values_from_witness(rln_witness: &RLNWitnessInput) -> Result<RLNPro
     // Merkle tree root computations
     let root = compute_tree_root(
         &rln_witness.identity_secret,
-        &rln_witness.user_message_limit,
         &rln_witness.path_elements,
         &rln_witness.identity_path_index,
+        true,
     );
 
-    Ok(RLNProofValues {
+    RLNProofValues {
         y,
         nullifier,
         root,
         x: rln_witness.x,
-        external_nullifier: rln_witness.external_nullifier,
-    })
+        epoch: rln_witness.epoch,
+        rln_identifier: rln_witness.rln_identifier,
+    }
 }
 
 pub fn serialize_proof_values(rln_proof_values: &RLNProofValues) -> Vec<u8> {
     let mut serialized: Vec<u8> = Vec::new();
 
     serialized.append(&mut fr_to_bytes_le(&rln_proof_values.root));
-    serialized.append(&mut fr_to_bytes_le(&rln_proof_values.external_nullifier));
+    serialized.append(&mut fr_to_bytes_le(&rln_proof_values.epoch));
     serialized.append(&mut fr_to_bytes_le(&rln_proof_values.x));
     serialized.append(&mut fr_to_bytes_le(&rln_proof_values.y));
     serialized.append(&mut fr_to_bytes_le(&rln_proof_values.nullifier));
+    serialized.append(&mut fr_to_bytes_le(&rln_proof_values.rln_identifier));
 
     serialized
 }
@@ -329,7 +328,7 @@ pub fn deserialize_proof_values(serialized: &[u8]) -> (RLNProofValues, usize) {
     let (root, read) = bytes_le_to_fr(&serialized[all_read..]);
     all_read += read;
 
-    let (external_nullifier, read) = bytes_le_to_fr(&serialized[all_read..]);
+    let (epoch, read) = bytes_le_to_fr(&serialized[all_read..]);
     all_read += read;
 
     let (x, read) = bytes_le_to_fr(&serialized[all_read..]);
@@ -341,13 +340,17 @@ pub fn deserialize_proof_values(serialized: &[u8]) -> (RLNProofValues, usize) {
     let (nullifier, read) = bytes_le_to_fr(&serialized[all_read..]);
     all_read += read;
 
+    let (rln_identifier, read) = bytes_le_to_fr(&serialized[all_read..]);
+    all_read += read;
+
     (
         RLNProofValues {
             y,
             nullifier,
             root,
             x,
-            external_nullifier,
+            epoch,
+            rln_identifier,
         },
         all_read,
     )
@@ -356,14 +359,14 @@ pub fn deserialize_proof_values(serialized: &[u8]) -> (RLNProofValues, usize) {
 pub fn prepare_prove_input(
     identity_secret: Fr,
     id_index: usize,
-    external_nullifier: Fr,
+    epoch: Fr,
     signal: &[u8],
 ) -> Vec<u8> {
     let mut serialized: Vec<u8> = Vec::new();
 
     serialized.append(&mut fr_to_bytes_le(&identity_secret));
     serialized.append(&mut normalize_usize(id_index));
-    serialized.append(&mut fr_to_bytes_le(&external_nullifier));
+    serialized.append(&mut fr_to_bytes_le(&epoch));
     serialized.append(&mut normalize_usize(signal.len()));
     serialized.append(&mut signal.to_vec());
 
@@ -386,13 +389,15 @@ pub fn prepare_verify_input(proof_data: Vec<u8>, signal: &[u8]) -> Vec<u8> {
 ///////////////////////////////////////////////////////
 
 pub fn compute_tree_root(
-    identity_secret: &Fr,
-    user_message_limit: &Fr,
+    leaf: &Fr,
     path_elements: &[Fr],
     identity_path_index: &[u8],
+    hash_leaf: bool,
 ) -> Fr {
-    let id_commitment = poseidon_hash(&[*identity_secret]);
-    let mut root = poseidon_hash(&[id_commitment, *user_message_limit]);
+    let mut root = *leaf;
+    if hash_leaf {
+        root = poseidon_hash(&[root]);
+    }
 
     for i in 0..identity_path_index.len() {
         if identity_path_index[i] == 0 {
@@ -483,7 +488,11 @@ pub fn extended_seeded_keygen(signal: &[u8]) -> (Fr, Fr, Fr, Fr) {
     )
 }
 
-pub fn compute_id_secret(share1: (Fr, Fr), share2: (Fr, Fr)) -> Result<Fr, String> {
+pub fn compute_id_secret(
+    share1: (Fr, Fr),
+    share2: (Fr, Fr),
+    external_nullifier: Fr,
+) -> Result<Fr, String> {
     // Assuming a0 is the identity secret and a1 = poseidonHash([a0, external_nullifier]),
     // a (x,y) share satisfies the following relation
     // y = a_0 + x * a_1
@@ -497,7 +506,14 @@ pub fn compute_id_secret(share1: (Fr, Fr), share2: (Fr, Fr)) -> Result<Fr, Strin
     let a_0 = y1 - x1 * a_1;
 
     // If shares come from the same polynomial, a0 is correctly recovered and a1 = poseidonHash([a0, external_nullifier])
-    Ok(a_0)
+    let computed_a_1 = poseidon_hash(&[a_0, external_nullifier]);
+
+    if a_1 == computed_a_1 {
+        // We successfully recovered the identity secret
+        Ok(a_0)
+    } else {
+        Err("Cannot recover identity_secret_hash from provided shares".into())
+    }
 }
 
 ///////////////////////////////////////////////////////
@@ -578,17 +594,10 @@ pub fn generate_proof_with_witness(
     Ok(proof)
 }
 
-/// Formats inputs for witness calculation
-///
-/// # Errors
-///
-/// Returns an error if `rln_witness.message_id` is not within `rln_witness.user_message_limit`.
 pub fn inputs_for_witness_calculation(
     rln_witness: &RLNWitnessInput,
-) -> Result<[(&str, Vec<BigInt>); 7]> {
-    message_id_range_check(&rln_witness.message_id, &rln_witness.user_message_limit)?;
-
-    // We convert the path indexes to field elements
+) -> Result<[(&str, Vec<BigInt>); 6]> {
+    // We confert the path indexes to field elements
     // TODO: check if necessary
     let mut path_elements = Vec::new();
 
@@ -604,20 +613,16 @@ pub fn inputs_for_witness_calculation(
 
     Ok([
         (
-            "identitySecret",
+            "identity_secret",
             vec![to_bigint(&rln_witness.identity_secret)?],
         ),
-        (
-            "userMessageLimit",
-            vec![to_bigint(&rln_witness.user_message_limit)?],
-        ),
-        ("messageId", vec![to_bigint(&rln_witness.message_id)?]),
-        ("pathElements", path_elements),
-        ("identityPathIndex", identity_path_index),
+        ("path_elements", path_elements),
+        ("identity_path_index", identity_path_index),
         ("x", vec![to_bigint(&rln_witness.x)?]),
+        ("epoch", vec![to_bigint(&rln_witness.epoch)?]),
         (
-            "externalNullifier",
-            vec![to_bigint(&rln_witness.external_nullifier)?],
+            "rln_identifier",
+            vec![to_bigint(&rln_witness.rln_identifier)?],
         ),
     ])
 }
@@ -666,6 +671,7 @@ pub fn generate_proof(
     // If in debug mode, we measure and later print time take to compute proof
     #[cfg(debug_assertions)]
     let now = Instant::now();
+
     let proof = Groth16::<_, CircomReduction>::create_proof_with_reduction_and_matrices(
         &proving_key.0,
         r,
@@ -699,7 +705,8 @@ pub fn verify_proof(
         proof_values.root,
         proof_values.nullifier,
         proof_values.x,
-        proof_values.external_nullifier,
+        proof_values.epoch,
+        proof_values.rln_identifier,
     ];
 
     // Check that the proof is valid
@@ -718,60 +725,11 @@ pub fn verify_proof(
     Ok(verified)
 }
 
-// auxiliary function for serialisation Fr to json using ark serilize
-fn ark_se<S, A: CanonicalSerialize>(a: &A, s: S) -> Result<S::Ok, S::Error>
-where
-    S: serde::Serializer,
-{
-    let mut bytes = vec![];
-    a.serialize_compressed(&mut bytes)
-        .map_err(serde::ser::Error::custom)?;
-    s.serialize_bytes(&bytes)
-}
-
-// auxiliary function for deserialisation Fr to json using ark serilize
-fn ark_de<'de, D, A: CanonicalDeserialize>(data: D) -> Result<A, D::Error>
-where
-    D: serde::de::Deserializer<'de>,
-{
-    let s: Vec<u8> = serde::de::Deserialize::deserialize(data)?;
-    let a = A::deserialize_compressed_unchecked(s.as_slice());
-    a.map_err(serde::de::Error::custom)
-}
-
-/// Converts a JSON value into [`RLNWitnessInput`](crate::protocol::RLNWitnessInput) object.
+/// Get CIRCOM JSON inputs
 ///
-/// # Errors
-///
-/// Returns an error if `rln_witness.message_id` is not within `rln_witness.user_message_limit`.
-pub fn rln_witness_from_json(input_json: serde_json::Value) -> Result<RLNWitnessInput> {
-    let rln_witness: RLNWitnessInput = serde_json::from_value(input_json).unwrap();
-    message_id_range_check(&rln_witness.message_id, &rln_witness.user_message_limit)?;
-
-    Ok(rln_witness)
-}
-
-/// Converts a [`RLNWitnessInput`](crate::protocol::RLNWitnessInput) object to the corresponding JSON serialization.
-///
-/// # Errors
-///
-/// Returns an error if `message_id` is not within `user_message_limit`.
-pub fn rln_witness_to_json(rln_witness: &RLNWitnessInput) -> Result<serde_json::Value> {
-    message_id_range_check(&rln_witness.message_id, &rln_witness.user_message_limit)?;
-
-    let rln_witness_json = serde_json::to_value(rln_witness)?;
-    Ok(rln_witness_json)
-}
-
-/// Converts a [`RLNWitnessInput`](crate::protocol::RLNWitnessInput) object to the corresponding JSON serialization.
-/// Before serialisation the data should be translated into big int for further calculation in the witness calculator.
-///
-/// # Errors
-///
-/// Returns an error if `message_id` is not within `user_message_limit`.
-pub fn rln_witness_to_bigint_json(rln_witness: &RLNWitnessInput) -> Result<serde_json::Value> {
-    message_id_range_check(&rln_witness.message_id, &rln_witness.user_message_limit)?;
-
+/// Returns a JSON object containing the inputs necessary to calculate
+/// the witness with CIRCOM on javascript
+pub fn get_json_inputs(rln_witness: &RLNWitnessInput) -> Result<serde_json::Value> {
     let mut path_elements = Vec::new();
 
     for v in rln_witness.path_elements.iter() {
@@ -785,23 +743,13 @@ pub fn rln_witness_to_bigint_json(rln_witness: &RLNWitnessInput) -> Result<serde
         .for_each(|v| identity_path_index.push(BigInt::from(*v).to_str_radix(10)));
 
     let inputs = serde_json::json!({
-        "identitySecret": to_bigint(&rln_witness.identity_secret)?.to_str_radix(10),
-        "userMessageLimit": to_bigint(&rln_witness.user_message_limit)?.to_str_radix(10),
-        "messageId": to_bigint(&rln_witness.message_id)?.to_str_radix(10),
-        "pathElements": path_elements,
-        "identityPathIndex": identity_path_index,
+        "identity_secret": to_bigint(&rln_witness.identity_secret)?.to_str_radix(10),
+        "path_elements": path_elements,
+        "identity_path_index": identity_path_index,
         "x": to_bigint(&rln_witness.x)?.to_str_radix(10),
-        "externalNullifier":  to_bigint(&rln_witness.external_nullifier)?.to_str_radix(10),
+        "epoch":  format!("0x{:064x}", to_bigint(&rln_witness.epoch)?),
+        "rln_identifier": to_bigint(&rln_witness.rln_identifier)?.to_str_radix(10),
     });
 
     Ok(inputs)
 }
-
-pub fn message_id_range_check(message_id: &Fr, user_message_limit: &Fr) -> Result<()> {
-    if message_id > user_message_limit {
-        return Err(color_eyre::Report::msg(
-            "message_id is not within user_message_limit",
-        ));
-    }
-    Ok(())
-}

rln/src/utils.rs

@@ -5,12 +5,10 @@ use ark_ff::PrimeField;
 use color_eyre::{Report, Result};
 use num_bigint::{BigInt, BigUint};
 use num_traits::Num;
-use serde_json::json;
-use std::io::Cursor;
 use std::iter::Extend;
 
 pub fn to_bigint(el: &Fr) -> Result<BigInt> {
-    let res: BigUint = (*el).into();
+    let res: BigUint = (*el).try_into()?;
     Ok(res.into())
 }
 
@@ -30,10 +28,10 @@ pub fn str_to_fr(input: &str, radix: u32) -> Result<Fr> {
     input_clean = input_clean.trim().to_string();
 
     if radix == 10 {
-        Ok(BigUint::from_str_radix(&input_clean, radix)?.into())
+        Ok(BigUint::from_str_radix(&input_clean, radix)?.try_into()?)
     } else {
         input_clean = input_clean.replace("0x", "");
-        Ok(BigUint::from_str_radix(&input_clean, radix)?.into())
+        Ok(BigUint::from_str_radix(&input_clean, radix)?.try_into()?)
     }
 }
 
@@ -181,24 +179,6 @@ pub fn normalize_usize(input: usize) -> Vec<u8> {
     normalized_usize
 }
 
-pub fn bytes_le_to_vec_usize(input: &[u8]) -> Result<Vec<usize>> {
-    let nof_elem = usize::try_from(u64::from_le_bytes(input[0..8].try_into()?))?;
-    if nof_elem == 0 {
-        Ok(vec![])
-    } else {
-        let elements: Vec<usize> = input[8..]
-            .chunks(8)
-            .map(|ch| usize::from_le_bytes(ch[0..8].try_into().unwrap()))
-            .collect();
-        Ok(elements)
-    }
-}
-
-// using for test
-pub fn generate_input_buffer() -> Cursor<String> {
-    Cursor::new(json!({}).to_string())
-}
-
 /* Old conversion utilities between different libraries data types
 
 // Conversion Utilities between poseidon-rs Field and arkworks Fr (in order to call directly poseidon-rs' poseidon_hash)

rln/tests/poseidon_tree.rs

@@ -4,25 +4,48 @@
 
 #[cfg(test)]
 mod test {
-    use rln::hashers::{poseidon_hash, PoseidonHash};
-    use rln::{circuit::*, poseidon_tree::PoseidonTree};
+    use rln::circuit::*;
+    use rln::hashers::PoseidonHash;
     use utils::{FullMerkleTree, OptimalMerkleTree, ZerokitMerkleProof, ZerokitMerkleTree};
 
     #[test]
-    // The test is checked correctness for `FullMerkleTree` and `OptimalMerkleTree` with Poseidon hash
-    fn test_zerokit_merkle_implementations() {
+    /// A basic performance comparison between the two supported Merkle Tree implementations
+    fn test_zerokit_merkle_implementations_performances() {
+        use std::time::{Duration, Instant};
+
+        let tree_height = 20;
         let sample_size = 100;
+
         let leaves: Vec<Fr> = (0..sample_size).map(|s| Fr::from(s)).collect();
 
-        let mut tree_full = FullMerkleTree::<PoseidonHash>::default(TEST_TREE_HEIGHT).unwrap();
-        let mut tree_opt = OptimalMerkleTree::<PoseidonHash>::default(TEST_TREE_HEIGHT).unwrap();
+        let mut gen_time_full: u128 = 0;
+        let mut upd_time_full: u128 = 0;
+        let mut gen_time_opt: u128 = 0;
+        let mut upd_time_opt: u128 = 0;
+
+        for _ in 0..sample_size.try_into().unwrap() {
+            let now = Instant::now();
+            FullMerkleTree::<PoseidonHash>::default(tree_height).unwrap();
+            gen_time_full += now.elapsed().as_nanos();
+
+            let now = Instant::now();
+            OptimalMerkleTree::<PoseidonHash>::default(tree_height).unwrap();
+            gen_time_opt += now.elapsed().as_nanos();
+        }
+
+        let mut tree_full = FullMerkleTree::<PoseidonHash>::default(tree_height).unwrap();
+        let mut tree_opt = OptimalMerkleTree::<PoseidonHash>::default(tree_height).unwrap();
 
         for i in 0..sample_size.try_into().unwrap() {
+            let now = Instant::now();
             tree_full.set(i, leaves[i]).unwrap();
+            upd_time_full += now.elapsed().as_nanos();
             let proof = tree_full.proof(i).expect("index should be set");
             assert_eq!(proof.leaf_index(), i);
 
+            let now = Instant::now();
             tree_opt.set(i, leaves[i]).unwrap();
+            upd_time_opt += now.elapsed().as_nanos();
             let proof = tree_opt.proof(i).expect("index should be set");
             assert_eq!(proof.leaf_index(), i);
         }
@@ -32,108 +55,26 @@ mod test {
         let tree_opt_root = tree_opt.root();
 
         assert_eq!(tree_full_root, tree_opt_root);
-    }
 
-    #[test]
-    fn test_subtree_root() {
-        const DEPTH: usize = 3;
-        const LEAVES_LEN: usize = 6;
-
-        let mut tree = PoseidonTree::default(DEPTH).unwrap();
-        let leaves: Vec<Fr> = (0..LEAVES_LEN).map(|s| Fr::from(s as i32)).collect();
-        let _ = tree.set_range(0, leaves);
-
-        for i in 0..LEAVES_LEN {
-            // check leaves
-            assert_eq!(
-                tree.get(i).unwrap(),
-                tree.get_subtree_root(DEPTH, i).unwrap()
-            );
-            // check root
-            assert_eq!(tree.root(), tree.get_subtree_root(0, i).unwrap());
-        }
-
-        // check intermediate nodes
-        for n in (1..=DEPTH).rev() {
-            for i in (0..(1 << n)).step_by(2) {
-                let idx_l = i * (1 << (DEPTH - n));
-                let idx_r = (i + 1) * (1 << (DEPTH - n));
-                let idx_sr = idx_l;
-
-                let prev_l = tree.get_subtree_root(n, idx_l).unwrap();
-                let prev_r = tree.get_subtree_root(n, idx_r).unwrap();
-                let subroot = tree.get_subtree_root(n - 1, idx_sr).unwrap();
-
-                assert_eq!(poseidon_hash(&[prev_l, prev_r]), subroot);
-            }
-        }
-    }
-
-    #[test]
-    fn test_get_empty_leaves_indices() {
-        let depth = 4;
-        let nof_leaves: usize = 1 << (depth - 1);
-
-        let mut tree = PoseidonTree::default(depth).unwrap();
-        let leaves: Vec<Fr> = (0..nof_leaves).map(|s| Fr::from(s as i32)).collect();
-
-        // check set_range
-        let _ = tree.set_range(0, leaves.clone());
-        assert!(tree.get_empty_leaves_indices().is_empty());
-
-        let mut vec_idxs = Vec::new();
-        // check delete function
-        for i in 0..nof_leaves {
-            vec_idxs.push(i);
-            let _ = tree.delete(i);
-            assert_eq!(tree.get_empty_leaves_indices(), vec_idxs);
-        }
-        // check set function
-        for i in (0..nof_leaves).rev() {
-            vec_idxs.pop();
-            let _ = tree.set(i, leaves[i]);
-            assert_eq!(tree.get_empty_leaves_indices(), vec_idxs);
-        }
-
-        // check remove_indices_and_set_leaves inside override_range function
-        assert!(tree.get_empty_leaves_indices().is_empty());
-        let leaves_2: Vec<Fr> = (0..2).map(|s| Fr::from(s as i32)).collect();
-        tree.override_range(0, leaves_2.clone(), [0, 1, 2, 3])
-            .unwrap();
-        assert_eq!(tree.get_empty_leaves_indices(), vec![2, 3]);
-
-        // check remove_indices inside override_range function
-        tree.override_range(0, [], [0, 1]).unwrap();
-        assert_eq!(tree.get_empty_leaves_indices(), vec![0, 1, 2, 3]);
-
-        // check set_range inside override_range function
-        tree.override_range(0, leaves_2.clone(), []).unwrap();
-        assert_eq!(tree.get_empty_leaves_indices(), vec![2, 3]);
-
-        let leaves_4: Vec<Fr> = (0..4).map(|s| Fr::from(s as i32)).collect();
-        // check if the indexes for write and delete are the same
-        tree.override_range(0, leaves_4.clone(), [0, 1, 2, 3])
-            .unwrap();
-        assert!(tree.get_empty_leaves_indices().is_empty());
-
-        // check if indexes for deletion are before indexes for overwriting
-        tree.override_range(4, leaves_4.clone(), [0, 1, 2, 3])
-            .unwrap();
-        // The result will be like this, because in the set_range function in pmtree
-        // the next_index value is increased not by the number of elements to insert,
-        // but by the union of indices for deleting and inserting.
-        assert_eq!(
-            tree.get_empty_leaves_indices(),
-            vec![0, 1, 2, 3, 8, 9, 10, 11]
+        println!(" Average tree generation time:");
+        println!(
+            "   - Full Merkle Tree:  {:?}",
+            Duration::from_nanos((gen_time_full / sample_size).try_into().unwrap())
+        );
+        println!(
+            "   - Optimal Merkle Tree: {:?}",
+            Duration::from_nanos((gen_time_opt / sample_size).try_into().unwrap())
         );
 
-        // check if the indices for write and delete do not overlap completely
-        tree.override_range(2, leaves_4.clone(), [0, 1, 2, 3])
-            .unwrap();
-        // The result will be like this, because in the set_range function in pmtree
-        // the next_index value is increased not by the number of elements to insert,
-        // but by the union of indices for deleting and inserting.
-        // + we've already set to 6 and 7 in previous test
-        assert_eq!(tree.get_empty_leaves_indices(), vec![0, 1, 8, 9, 10, 11]);
+        println!(" Average update_next execution time:");
+        println!(
+            "   - Full Merkle Tree: {:?}",
+            Duration::from_nanos((upd_time_full / sample_size).try_into().unwrap())
+        );
+
+        println!(
+            "   - Optimal Merkle Tree: {:?}",
+            Duration::from_nanos((upd_time_opt / sample_size).try_into().unwrap())
+        );
     }
 }

rln/tests/protocol.rs

@@ -1,8 +1,9 @@
 #[cfg(test)]
 mod test {
-    use ark_ff::BigInt;
-    use rln::circuit::zkey_from_folder;
-    use rln::circuit::{circom_from_folder, vk_from_folder, Fr, TEST_TREE_HEIGHT};
+    use rln::circuit::{
+        circom_from_folder, vk_from_folder, zkey_from_folder, Fr, TEST_RESOURCES_FOLDER,
+        TEST_TREE_HEIGHT,
+    };
     use rln::hashers::{hash_to_field, poseidon_hash};
     use rln::poseidon_tree::PoseidonTree;
     use rln::protocol::*;
@@ -11,135 +12,365 @@ mod test {
 
     type ConfigOf<T> = <T as ZerokitMerkleTree>::Config;
 
+    // Input generated with https://github.com/oskarth/zk-kit/commit/b6a872f7160c7c14e10a0ea40acab99cbb23c9a8
+    const WITNESS_JSON_15: &str = r#"
+            {
+              "identity_secret": "12825549237505733615964533204745049909430608936689388901883576945030025938736",
+              "path_elements": [
+                "18622655742232062119094611065896226799484910997537830749762961454045300666333",
+                "20590447254980891299813706518821659736846425329007960381537122689749540452732",
+                "7423237065226347324353380772367382631490014989348495481811164164159255474657",
+                "11286972368698509976183087595462810875513684078608517520839298933882497716792",
+                "3607627140608796879659380071776844901612302623152076817094415224584923813162",
+                "19712377064642672829441595136074946683621277828620209496774504837737984048981",
+                "20775607673010627194014556968476266066927294572720319469184847051418138353016",
+                "3396914609616007258851405644437304192397291162432396347162513310381425243293",
+                "21551820661461729022865262380882070649935529853313286572328683688269863701601",
+                "6573136701248752079028194407151022595060682063033565181951145966236778420039",
+                "12413880268183407374852357075976609371175688755676981206018884971008854919922",
+                "14271763308400718165336499097156975241954733520325982997864342600795471836726",
+                "20066985985293572387227381049700832219069292839614107140851619262827735677018",
+                "9394776414966240069580838672673694685292165040808226440647796406499139370960",
+                "11331146992410411304059858900317123658895005918277453009197229807340014528524"
+              ],
+              "identity_path_index": [
+                1,
+                1,
+                0,
+                0,
+                0,
+                0,
+                0,
+                0,
+                0,
+                0,
+                0,
+                0,
+                0,
+                0,
+                0
+              ],
+              "x": "8143228284048792769012135629627737459844825626241842423967352803501040982",
+              "epoch": "0x0000005b612540fc986b42322f8cb91c2273afad58ed006fdba0c97b4b16b12f",
+              "rln_identifier": "11412926387081627876309792396682864042420635853496105400039841573530884328439"
+            }
+        "#;
+
+    // Input generated with protocol::random_rln_witness
+    const WITNESS_JSON_19: &str = r#"
+            {
+              "identity_secret": "922538810348594125658702672067738675294669207539999802857585668079702330450",
+              "path_elements": [
+                  "16059714054680148404543504061485737353203416489071538960876865983954285286166",
+                  "3041470753871943901334053763207316028823782848445723460227667780327106380356",
+                  "2557297527793326315072058421057853700096944625924483912548759909801348042183",
+                  "6677578602456189582427063963562590713054668181987223110955234085327917303436",
+                  "2250827150965576973906150764756422151438812678308727218463995574869267980301",
+                  "1895457427602709606993445561553433669787657053834360973759981803464906070980",
+                  "11033689991077061346803816826729204895841441316315304395980565540264104346466",
+                  "18588752216879570844240300406954267039026327526134910835334500497981810174976",
+                  "19346480964028499661277403659363466542857230928032088490855656809181891953123",
+                  "21460193770370072688835316363068413651465631481105148051902686770759127189327",
+                  "20906347653364838502964722817589315918082261023317339146393355650507243340078",
+                  "13466599592974387800162739317046838825289754472645703919149409009404541432954",
+                  "9617165663598957201253074168824246164494443748556931540348223968573884172285",
+                  "6936463137584425684797785981770877165377386163416057257854261010817156666898",
+                  "369902028235468424790098825415813437044876310542601948037281422841675126849",
+                  "13510969869821080499683463562609720931680005714401083864659516045615497273644",
+                  "2567921390740781421487331055530491683313154421589525170472201828596388395736",
+                  "14360870889466292805403568662660511177232987619663547772298178013674025998478",
+                  "4735344599616284973799984501493858013178071155960162022656706545116168334293"
+              ],
+              "identity_path_index": [
+                  1,
+                  0,
+                  1,
+                  0,
+                  1,
+                  1,
+                  0,
+                  0,
+                  1,
+                  1,
+                  1,
+                  0,
+                  0,
+                  0,
+                  1,
+                  0,
+                  1,
+                  1,
+                  0
+              ],
+              "x": "6427050788896290028100534859169645070970780055911091444144195464808120686416",
+              "epoch": "0x2bd155d9f85c741044da6909d144f9cc5ce8e0d545a9ed4921b156e8b8569bab",
+              "rln_identifier": "2193983000213424579594329476781986065965849144986973472766961413131458022566"
+            }
+        "#;
+
+    const WITNESS_JSON_20: &str = r#"
+            {
+              "identity_secret": "13732353453861280511150022598793312186188599006979552959297495195757997428306",
+              "path_elements": [
+                  "20463525608687844300981085488128968694844212760055234622292326942405619575964",
+                  "8040856403709217901175408904825741112286158901303127670929462145501210871313",
+                  "3776499751255585163563840252112871568402966629435152937692711318702338789837",
+                  "19415813252626942110541463414404411443562242499365750694284604341271149125679",
+                  "19414720788761208006634240390286942738242262010168559813148115573784354129237",
+                  "17680594732844291740094158892269696200077963275550625226493856898849422516043",
+                  "16009199741350632715210088346611798597033333293348807000623441780059543674510",
+                  "18743496911007535170857676824393811326863602477260615792503039058813338644738",
+                  "1029572792321380246989475723806770724699749375691788486434716005338938722216",
+                  "21713138150151063186050010182615713685603650963220209951496401043119768920892",
+                  "6713732504049401389983008178456811894856018247924860823028704114266363984580",
+                  "2746686888799473963221285145390361693256731812094259845879519459924507786594",
+                  "18620748467731297359505500266677881218553438497271819903304075323783392031715",
+                  "2446201221122671119406471414204229600430018713181038717206670749886932158104",
+                  "12037171942017611311954851302868199608036334625783560875426350283156617524597",
+                  "21798743392351780927808323348278035105395367759688979232116905142049921734349",
+                  "17450230289417496971557215666910229260621413088991137405744457922069827319039",
+                  "20936854099128086256353520300046664152516566958630447858438908748907198510485",
+                  "13513344965831154386658059617477268600255664386844920822248038939666265737046",
+                  "15546319496880899251450021422131511560001766832580480193115646510655765306630"
+
+              ],
+              "identity_path_index": [
+                  0,
+                  1,
+                  0,
+                  0,
+                  1,
+                  1,
+                  0,
+                  0,
+                  1,
+                  1,
+                  0,
+                  0,
+                  0,
+                  1,
+                  0,
+                  1,
+                  1,
+                  0,
+                  0,
+                  0
+              ],
+              "x": "18073935665561339809445069958310044423750771681863480888589546877024349720547",
+              "epoch": "0x147e4c23a43a1ddca78d94bcd28147f62ca74b3dc7e56bb0a314a954b9f0e567",
+              "rln_identifier": "2193983000213424579594329476781986065965849144986973472766961413131458022566"
+            }
+        "#;
+
     #[test]
     // We test Merkle tree generation, proofs and verification
     fn test_merkle_proof() {
+        let tree_height = TEST_TREE_HEIGHT;
         let leaf_index = 3;
 
         // generate identity
         let identity_secret_hash = hash_to_field(b"test-merkle-proof");
-        let id_commitment = poseidon_hash(&[identity_secret_hash]);
-        let rate_commitment = poseidon_hash(&[id_commitment, 100.into()]);
+        let id_commitment = poseidon_hash(&vec![identity_secret_hash]);
 
         // generate merkle tree
         let default_leaf = Fr::from(0);
         let mut tree = PoseidonTree::new(
-            TEST_TREE_HEIGHT,
+            tree_height,
             default_leaf,
             ConfigOf::<PoseidonTree>::default(),
         )
         .unwrap();
-        tree.set(leaf_index, rate_commitment.into()).unwrap();
+        tree.set(leaf_index, id_commitment.into()).unwrap();
 
         // We check correct computation of the root
         let root = tree.root();
 
-        assert_eq!(
-            root,
-            BigInt([
-                4939322235247991215,
-                5110804094006647505,
-                4427606543677101242,
-                910933464535675827
-            ])
-            .into()
-        );
+        if TEST_TREE_HEIGHT == 15 {
+            assert_eq!(
+                root,
+                str_to_fr(
+                    "0x1984f2e01184aef5cb974640898a5f5c25556554e2b06d99d4841badb8b198cd",
+                    16
+                )
+                .unwrap()
+            );
+        } else if TEST_TREE_HEIGHT == 19 {
+            assert_eq!(
+                root,
+                str_to_fr(
+                    "0x219ceb53f2b1b7a6cf74e80d50d44d68ecb4a53c6cc65b25593c8d56343fb1fe",
+                    16
+                )
+                .unwrap()
+            );
+        } else if TEST_TREE_HEIGHT == 20 {
+            assert_eq!(
+                root,
+                str_to_fr(
+                    "0x21947ffd0bce0c385f876e7c97d6a42eec5b1fe935aab2f01c1f8a8cbcc356d2",
+                    16
+                )
+                .unwrap()
+            );
+        }
 
         let merkle_proof = tree.proof(leaf_index).expect("proof should exist");
         let path_elements = merkle_proof.get_path_elements();
         let identity_path_index = merkle_proof.get_path_index();
 
         // We check correct computation of the path and indexes
-        let expected_path_elements: Vec<Fr> = [
-            "0x0000000000000000000000000000000000000000000000000000000000000000",
-            "0x2098f5fb9e239eab3ceac3f27b81e481dc3124d55ffed523a839ee8446b64864",
-            "0x1069673dcdb12263df301a6ff584a7ec261a44cb9dc68df067a4774460b1f1e1",
-            "0x18f43331537ee2af2e3d758d50f72106467c6eea50371dd528d57eb2b856d238",
-            "0x07f9d837cb17b0d36320ffe93ba52345f1b728571a568265caac97559dbc952a",
-            "0x2b94cf5e8746b3f5c9631f4c5df32907a699c58c94b2ad4d7b5cec1639183f55",
-            "0x2dee93c5a666459646ea7d22cca9e1bcfed71e6951b953611d11dda32ea09d78",
-            "0x078295e5a22b84e982cf601eb639597b8b0515a88cb5ac7fa8a4aabe3c87349d",
-            "0x2fa5e5f18f6027a6501bec864564472a616b2e274a41211a444cbe3a99f3cc61",
-            "0x0e884376d0d8fd21ecb780389e941f66e45e7acce3e228ab3e2156a614fcd747",
-            "0x1b7201da72494f1e28717ad1a52eb469f95892f957713533de6175e5da190af2",
-            "0x1f8d8822725e36385200c0b201249819a6e6e1e4650808b5bebc6bface7d7636",
-            "0x2c5d82f66c914bafb9701589ba8cfcfb6162b0a12acf88a8d0879a0471b5f85a",
-            "0x14c54148a0940bb820957f5adf3fa1134ef5c4aaa113f4646458f270e0bfbfd0",
-            "0x190d33b12f986f961e10c0ee44d8b9af11be25588cad89d416118e4bf4ebe80c",
-            "0x22f98aa9ce704152ac17354914ad73ed1167ae6596af510aa5b3649325e06c92",
-            "0x2a7c7c9b6ce5880b9f6f228d72bf6a575a526f29c66ecceef8b753d38bba7323",
-            "0x2e8186e558698ec1c67af9c14d463ffc470043c9c2988b954d75dd643f36b992",
-            "0x0f57c5571e9a4eab49e2c8cf050dae948aef6ead647392273546249d1c1ff10f",
-            "0x1830ee67b5fb554ad5f63d4388800e1cfe78e310697d46e43c9ce36134f72cca",
-        ]
-        .map(|e| str_to_fr(e, 16).unwrap())
-        .to_vec();
+        // These values refers to TEST_TREE_HEIGHT == 16
+        let mut expected_path_elements = vec![
+            str_to_fr(
+                "0x0000000000000000000000000000000000000000000000000000000000000000",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x2098f5fb9e239eab3ceac3f27b81e481dc3124d55ffed523a839ee8446b64864",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x1069673dcdb12263df301a6ff584a7ec261a44cb9dc68df067a4774460b1f1e1",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x18f43331537ee2af2e3d758d50f72106467c6eea50371dd528d57eb2b856d238",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x07f9d837cb17b0d36320ffe93ba52345f1b728571a568265caac97559dbc952a",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x2b94cf5e8746b3f5c9631f4c5df32907a699c58c94b2ad4d7b5cec1639183f55",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x2dee93c5a666459646ea7d22cca9e1bcfed71e6951b953611d11dda32ea09d78",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x078295e5a22b84e982cf601eb639597b8b0515a88cb5ac7fa8a4aabe3c87349d",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x2fa5e5f18f6027a6501bec864564472a616b2e274a41211a444cbe3a99f3cc61",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x0e884376d0d8fd21ecb780389e941f66e45e7acce3e228ab3e2156a614fcd747",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x1b7201da72494f1e28717ad1a52eb469f95892f957713533de6175e5da190af2",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x1f8d8822725e36385200c0b201249819a6e6e1e4650808b5bebc6bface7d7636",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x2c5d82f66c914bafb9701589ba8cfcfb6162b0a12acf88a8d0879a0471b5f85a",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x14c54148a0940bb820957f5adf3fa1134ef5c4aaa113f4646458f270e0bfbfd0",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x190d33b12f986f961e10c0ee44d8b9af11be25588cad89d416118e4bf4ebe80c",
+                16,
+            )
+            .unwrap(),
+        ];
 
-        let expected_identity_path_index: Vec<u8> =
-            vec![1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
+        let mut expected_identity_path_index: Vec<u8> =
+            vec![1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
+
+        // We add the remaining elements for the case TEST_TREE_HEIGHT = 20
+        if TEST_TREE_HEIGHT == 19 || TEST_TREE_HEIGHT == 20 {
+            expected_path_elements.append(&mut vec![
+                str_to_fr(
+                    "0x22f98aa9ce704152ac17354914ad73ed1167ae6596af510aa5b3649325e06c92",
+                    16,
+                )
+                .unwrap(),
+                str_to_fr(
+                    "0x2a7c7c9b6ce5880b9f6f228d72bf6a575a526f29c66ecceef8b753d38bba7323",
+                    16,
+                )
+                .unwrap(),
+                str_to_fr(
+                    "0x2e8186e558698ec1c67af9c14d463ffc470043c9c2988b954d75dd643f36b992",
+                    16,
+                )
+                .unwrap(),
+                str_to_fr(
+                    "0x0f57c5571e9a4eab49e2c8cf050dae948aef6ead647392273546249d1c1ff10f",
+                    16,
+                )
+                .unwrap(),
+            ]);
+            expected_identity_path_index.append(&mut vec![0, 0, 0, 0]);
+        }
+
+        if TEST_TREE_HEIGHT == 20 {
+            expected_path_elements.append(&mut vec![str_to_fr(
+                "0x1830ee67b5fb554ad5f63d4388800e1cfe78e310697d46e43c9ce36134f72cca",
+                16,
+            )
+            .unwrap()]);
+            expected_identity_path_index.append(&mut vec![0]);
+        }
 
         assert_eq!(path_elements, expected_path_elements);
         assert_eq!(identity_path_index, expected_identity_path_index);
 
         // We check correct verification of the proof
-        assert!(tree.verify(&rate_commitment, &merkle_proof).unwrap());
-    }
-
-    fn get_test_witness() -> RLNWitnessInput {
-        let leaf_index = 3;
-        // Generate identity pair
-        let (identity_secret_hash, id_commitment) = keygen();
-        let user_message_limit = Fr::from(100);
-        let rate_commitment = poseidon_hash(&[id_commitment, user_message_limit]);
-
-        //// generate merkle tree
-        let default_leaf = Fr::from(0);
-        let mut tree = PoseidonTree::new(
-            TEST_TREE_HEIGHT,
-            default_leaf,
-            ConfigOf::<PoseidonTree>::default(),
-        )
-        .unwrap();
-        tree.set(leaf_index, rate_commitment.into()).unwrap();
-
-        let merkle_proof = tree.proof(leaf_index).expect("proof should exist");
-
-        let signal = b"hey hey";
-        let x = hash_to_field(signal);
-
-        // We set the remaining values to random ones
-        let epoch = hash_to_field(b"test-epoch");
-        let rln_identifier = hash_to_field(b"test-rln-identifier");
-        let external_nullifier = poseidon_hash(&[epoch, rln_identifier]);
-
-        rln_witness_from_values(
-            identity_secret_hash,
-            &merkle_proof,
-            x,
-            external_nullifier,
-            user_message_limit,
-            Fr::from(1),
-        )
-        .unwrap()
+        assert!(tree.verify(&id_commitment, &merkle_proof).unwrap());
     }
 
     #[test]
     // We test a RLN proof generation and verification
     fn test_witness_from_json() {
         // We generate all relevant keys
-        let proving_key = zkey_from_folder();
-        let verification_key = vk_from_folder();
-        let builder = circom_from_folder();
+        let proving_key = zkey_from_folder(TEST_RESOURCES_FOLDER).unwrap();
+        let verification_key = vk_from_folder(TEST_RESOURCES_FOLDER).unwrap();
+        let builder = circom_from_folder(TEST_RESOURCES_FOLDER).unwrap();
 
-        // We compute witness from the json input
-        let rln_witness = get_test_witness();
-        let rln_witness_json = rln_witness_to_json(&rln_witness).unwrap();
-        let rln_witness_deser = rln_witness_from_json(rln_witness_json).unwrap();
-        assert_eq!(rln_witness_deser, rln_witness);
+        // We compute witness from the json input example
+        let mut witness_json: &str = "";
+
+        if TEST_TREE_HEIGHT == 15 {
+            witness_json = WITNESS_JSON_15;
+        } else if TEST_TREE_HEIGHT == 19 {
+            witness_json = WITNESS_JSON_19;
+        } else if TEST_TREE_HEIGHT == 20 {
+            witness_json = WITNESS_JSON_20;
+        }
+
+        let rln_witness = rln_witness_from_json(witness_json);
+
+        let rln_witness_unwrapped = rln_witness.unwrap();
 
         // Let's generate a zkSNARK proof
-        let proof = generate_proof(builder, &proving_key, &rln_witness_deser).unwrap();
-        let proof_values = proof_values_from_witness(&rln_witness_deser).unwrap();
+        let proof = generate_proof(builder, &proving_key, &rln_witness_unwrapped).unwrap();
+
+        let proof_values = proof_values_from_witness(&rln_witness_unwrapped);
 
         // Let's verify the proof
         let verified = verify_proof(&verification_key, &proof, &proof_values);
@@ -150,20 +381,47 @@ mod test {
     #[test]
     // We test a RLN proof generation and verification
     fn test_end_to_end() {
-        let rln_witness = get_test_witness();
-        let rln_witness_json = rln_witness_to_json(&rln_witness).unwrap();
-        let rln_witness_deser = rln_witness_from_json(rln_witness_json).unwrap();
-        assert_eq!(rln_witness_deser, rln_witness);
+        let tree_height = TEST_TREE_HEIGHT;
+        let leaf_index = 3;
+
+        // Generate identity pair
+        let (identity_secret_hash, id_commitment) = keygen();
+
+        //// generate merkle tree
+        let default_leaf = Fr::from(0);
+        let mut tree = PoseidonTree::new(
+            tree_height,
+            default_leaf,
+            ConfigOf::<PoseidonTree>::default(),
+        )
+        .unwrap();
+        tree.set(leaf_index, id_commitment.into()).unwrap();
+
+        let merkle_proof = tree.proof(leaf_index).expect("proof should exist");
+
+        let signal = b"hey hey";
+        let x = hash_to_field(signal);
+
+        // We set the remaining values to random ones
+        let epoch = hash_to_field(b"test-epoch");
+        //let rln_identifier = hash_to_field(b"test-rln-identifier");
+
+        let rln_witness: RLNWitnessInput = rln_witness_from_values(
+            identity_secret_hash,
+            &merkle_proof,
+            x,
+            epoch, /*, rln_identifier*/
+        );
 
         // We generate all relevant keys
-        let proving_key = zkey_from_folder();
-        let verification_key = vk_from_folder();
-        let builder = circom_from_folder();
+        let proving_key = zkey_from_folder(TEST_RESOURCES_FOLDER).unwrap();
+        let verification_key = vk_from_folder(TEST_RESOURCES_FOLDER).unwrap();
+        let builder = circom_from_folder(TEST_RESOURCES_FOLDER).unwrap();
 
         // Let's generate a zkSNARK proof
-        let proof = generate_proof(builder, &proving_key, &rln_witness_deser).unwrap();
+        let proof = generate_proof(builder, &proving_key, &rln_witness).unwrap();
 
-        let proof_values = proof_values_from_witness(&rln_witness_deser).unwrap();
+        let proof_values = proof_values_from_witness(&rln_witness);
 
         // Let's verify the proof
         let success = verify_proof(&verification_key, &proof, &proof_values).unwrap();
@@ -173,19 +431,25 @@ mod test {
 
     #[test]
     fn test_witness_serialization() {
-        // We test witness JSON serialization
-        let rln_witness = get_test_witness();
-        let rln_witness_json = rln_witness_to_json(&rln_witness).unwrap();
-        let rln_witness_deser = rln_witness_from_json(rln_witness_json).unwrap();
-        assert_eq!(rln_witness_deser, rln_witness);
-
         // We test witness serialization
+        let mut witness_json: &str = "";
+
+        if TEST_TREE_HEIGHT == 15 {
+            witness_json = WITNESS_JSON_15;
+        } else if TEST_TREE_HEIGHT == 19 {
+            witness_json = WITNESS_JSON_19;
+        } else if TEST_TREE_HEIGHT == 20 {
+            witness_json = WITNESS_JSON_20;
+        }
+
+        let rln_witness = rln_witness_from_json(witness_json).unwrap();
+
         let ser = serialize_witness(&rln_witness).unwrap();
         let (deser, _) = deserialize_witness(&ser).unwrap();
         assert_eq!(rln_witness, deser);
 
         // We test Proof values serialization
-        let proof_values = proof_values_from_witness(&rln_witness).unwrap();
+        let proof_values = proof_values_from_witness(&rln_witness);
         let ser = serialize_proof_values(&proof_values);
         let (deser, _) = deserialize_proof_values(&ser);
         assert_eq!(proof_values, deser);

rln/tests/public.rs

@@ -1,59 +1,66 @@
 #[cfg(test)]
 mod test {
-    use ark_ff::BigInt;
     use ark_std::{rand::thread_rng, UniformRand};
     use rand::Rng;
-    use rln::circuit::{Fr, TEST_TREE_HEIGHT};
+    use rln::circuit::{Fr, TEST_RESOURCES_FOLDER, TEST_TREE_HEIGHT};
     use rln::hashers::{hash_to_field, poseidon_hash as utils_poseidon_hash, ROUND_PARAMS};
     use rln::protocol::{compute_tree_root, deserialize_identity_tuple};
     use rln::public::{hash as public_hash, poseidon_hash as public_poseidon_hash, RLN};
     use rln::utils::*;
+    use serde_json::json;
     use std::io::Cursor;
 
     #[test]
     // This test is similar to the one in lib, but uses only public API
-    #[cfg(not(feature = "stateless"))]
     fn test_merkle_proof() {
+        let tree_height = TEST_TREE_HEIGHT;
         let leaf_index = 3;
-        let user_message_limit = 1;
 
-        let mut rln = RLN::new(TEST_TREE_HEIGHT, generate_input_buffer()).unwrap();
+        let input_buffer =
+            Cursor::new(json!({ "resources_folder": TEST_RESOURCES_FOLDER }).to_string());
+        let mut rln = RLN::new(tree_height, input_buffer).unwrap();
 
         // generate identity
         let identity_secret_hash = hash_to_field(b"test-merkle-proof");
         let id_commitment = utils_poseidon_hash(&vec![identity_secret_hash]);
-        let rate_commitment = utils_poseidon_hash(&[id_commitment, user_message_limit.into()]);
 
-        // check that leaves indices is empty
-        let mut buffer = Cursor::new(Vec::<u8>::new());
-        rln.get_empty_leaves_indices(&mut buffer).unwrap();
-        let idxs = bytes_le_to_vec_usize(&buffer.into_inner()).unwrap();
-        assert!(idxs.is_empty());
-
-        // We pass rate_commitment as Read buffer to RLN's set_leaf
-        let mut buffer = Cursor::new(fr_to_bytes_le(&rate_commitment));
+        // We pass id_commitment as Read buffer to RLN's set_leaf
+        let mut buffer = Cursor::new(fr_to_bytes_le(&id_commitment));
         rln.set_leaf(leaf_index, &mut buffer).unwrap();
 
-        // check that leaves before leaf_index is set to zero
-        let mut buffer = Cursor::new(Vec::<u8>::new());
-        rln.get_empty_leaves_indices(&mut buffer).unwrap();
-        let idxs = bytes_le_to_vec_usize(&buffer.into_inner()).unwrap();
-        assert_eq!(idxs, [0, 1, 2]);
-
         // We check correct computation of the root
         let mut buffer = Cursor::new(Vec::<u8>::new());
         rln.get_root(&mut buffer).unwrap();
         let (root, _) = bytes_le_to_fr(&buffer.into_inner());
 
-        assert_eq!(
-            root,
-            Fr::from(BigInt([
-                17110646155607829651,
-                5040045984242729823,
-                6965416728592533086,
-                2328960363755461975
-            ]))
-        );
+        if TEST_TREE_HEIGHT == 15 {
+            assert_eq!(
+                root,
+                str_to_fr(
+                    "0x1984f2e01184aef5cb974640898a5f5c25556554e2b06d99d4841badb8b198cd",
+                    16
+                )
+                .unwrap()
+            );
+        } else if TEST_TREE_HEIGHT == 19 {
+            assert_eq!(
+                root,
+                str_to_fr(
+                    "0x219ceb53f2b1b7a6cf74e80d50d44d68ecb4a53c6cc65b25593c8d56343fb1fe",
+                    16
+                )
+                .unwrap()
+            );
+        } else if TEST_TREE_HEIGHT == 20 {
+            assert_eq!(
+                root,
+                str_to_fr(
+                    "0x21947ffd0bce0c385f876e7c97d6a42eec5b1fe935aab2f01c1f8a8cbcc356d2",
+                    16
+                )
+                .unwrap()
+            );
+        }
 
         // We check correct computation of merkle proof
         let mut buffer = Cursor::new(Vec::<u8>::new());
@@ -64,67 +71,129 @@ mod test {
         let (identity_path_index, _) = bytes_le_to_vec_u8(&buffer_inner[read..].to_vec()).unwrap();
 
         // We check correct computation of the path and indexes
-        let expected_path_elements: Vec<Fr> = [
-            "0x0000000000000000000000000000000000000000000000000000000000000000",
-            "0x2098f5fb9e239eab3ceac3f27b81e481dc3124d55ffed523a839ee8446b64864",
-            "0x1069673dcdb12263df301a6ff584a7ec261a44cb9dc68df067a4774460b1f1e1",
-            "0x18f43331537ee2af2e3d758d50f72106467c6eea50371dd528d57eb2b856d238",
-            "0x07f9d837cb17b0d36320ffe93ba52345f1b728571a568265caac97559dbc952a",
-            "0x2b94cf5e8746b3f5c9631f4c5df32907a699c58c94b2ad4d7b5cec1639183f55",
-            "0x2dee93c5a666459646ea7d22cca9e1bcfed71e6951b953611d11dda32ea09d78",
-            "0x078295e5a22b84e982cf601eb639597b8b0515a88cb5ac7fa8a4aabe3c87349d",
-            "0x2fa5e5f18f6027a6501bec864564472a616b2e274a41211a444cbe3a99f3cc61",
-            "0x0e884376d0d8fd21ecb780389e941f66e45e7acce3e228ab3e2156a614fcd747",
-            "0x1b7201da72494f1e28717ad1a52eb469f95892f957713533de6175e5da190af2",
-            "0x1f8d8822725e36385200c0b201249819a6e6e1e4650808b5bebc6bface7d7636",
-            "0x2c5d82f66c914bafb9701589ba8cfcfb6162b0a12acf88a8d0879a0471b5f85a",
-            "0x14c54148a0940bb820957f5adf3fa1134ef5c4aaa113f4646458f270e0bfbfd0",
-            "0x190d33b12f986f961e10c0ee44d8b9af11be25588cad89d416118e4bf4ebe80c",
-            "0x22f98aa9ce704152ac17354914ad73ed1167ae6596af510aa5b3649325e06c92",
-            "0x2a7c7c9b6ce5880b9f6f228d72bf6a575a526f29c66ecceef8b753d38bba7323",
-            "0x2e8186e558698ec1c67af9c14d463ffc470043c9c2988b954d75dd643f36b992",
-            "0x0f57c5571e9a4eab49e2c8cf050dae948aef6ead647392273546249d1c1ff10f",
-            "0x1830ee67b5fb554ad5f63d4388800e1cfe78e310697d46e43c9ce36134f72cca",
-        ]
-        .map(|e| str_to_fr(e, 16).unwrap())
-        .to_vec();
+        let mut expected_path_elements = vec![
+            str_to_fr(
+                "0x0000000000000000000000000000000000000000000000000000000000000000",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x2098f5fb9e239eab3ceac3f27b81e481dc3124d55ffed523a839ee8446b64864",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x1069673dcdb12263df301a6ff584a7ec261a44cb9dc68df067a4774460b1f1e1",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x18f43331537ee2af2e3d758d50f72106467c6eea50371dd528d57eb2b856d238",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x07f9d837cb17b0d36320ffe93ba52345f1b728571a568265caac97559dbc952a",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x2b94cf5e8746b3f5c9631f4c5df32907a699c58c94b2ad4d7b5cec1639183f55",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x2dee93c5a666459646ea7d22cca9e1bcfed71e6951b953611d11dda32ea09d78",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x078295e5a22b84e982cf601eb639597b8b0515a88cb5ac7fa8a4aabe3c87349d",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x2fa5e5f18f6027a6501bec864564472a616b2e274a41211a444cbe3a99f3cc61",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x0e884376d0d8fd21ecb780389e941f66e45e7acce3e228ab3e2156a614fcd747",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x1b7201da72494f1e28717ad1a52eb469f95892f957713533de6175e5da190af2",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x1f8d8822725e36385200c0b201249819a6e6e1e4650808b5bebc6bface7d7636",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x2c5d82f66c914bafb9701589ba8cfcfb6162b0a12acf88a8d0879a0471b5f85a",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x14c54148a0940bb820957f5adf3fa1134ef5c4aaa113f4646458f270e0bfbfd0",
+                16,
+            )
+            .unwrap(),
+            str_to_fr(
+                "0x190d33b12f986f961e10c0ee44d8b9af11be25588cad89d416118e4bf4ebe80c",
+                16,
+            )
+            .unwrap(),
+        ];
 
-        let expected_identity_path_index: Vec<u8> =
-            vec![1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
+        let mut expected_identity_path_index: Vec<u8> =
+            vec![1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
+
+        // We add the remaining elements for the case TEST_TREE_HEIGHT = 20
+        if TEST_TREE_HEIGHT == 19 || TEST_TREE_HEIGHT == 20 {
+            expected_path_elements.append(&mut vec![
+                str_to_fr(
+                    "0x22f98aa9ce704152ac17354914ad73ed1167ae6596af510aa5b3649325e06c92",
+                    16,
+                )
+                .unwrap(),
+                str_to_fr(
+                    "0x2a7c7c9b6ce5880b9f6f228d72bf6a575a526f29c66ecceef8b753d38bba7323",
+                    16,
+                )
+                .unwrap(),
+                str_to_fr(
+                    "0x2e8186e558698ec1c67af9c14d463ffc470043c9c2988b954d75dd643f36b992",
+                    16,
+                )
+                .unwrap(),
+                str_to_fr(
+                    "0x0f57c5571e9a4eab49e2c8cf050dae948aef6ead647392273546249d1c1ff10f",
+                    16,
+                )
+                .unwrap(),
+            ]);
+            expected_identity_path_index.append(&mut vec![0, 0, 0, 0]);
+        }
+
+        if TEST_TREE_HEIGHT == 20 {
+            expected_path_elements.append(&mut vec![str_to_fr(
+                "0x1830ee67b5fb554ad5f63d4388800e1cfe78e310697d46e43c9ce36134f72cca",
+                16,
+            )
+            .unwrap()]);
+            expected_identity_path_index.append(&mut vec![0]);
+        }
 
         assert_eq!(path_elements, expected_path_elements);
         assert_eq!(identity_path_index, expected_identity_path_index);
 
-        // check subtree root computation for leaf 0 for all corresponding node until the root
-        let l_idx = 0;
-        for n in (1..=TEST_TREE_HEIGHT).rev() {
-            let idx_l = l_idx * (1 << (TEST_TREE_HEIGHT - n));
-            let idx_r = (l_idx + 1) * (1 << (TEST_TREE_HEIGHT - n));
-            let idx_sr = idx_l;
-
-            let mut buffer = Cursor::new(Vec::<u8>::new());
-            rln.get_subtree_root(n, idx_l, &mut buffer).unwrap();
-            let (prev_l, _) = bytes_le_to_fr(&buffer.into_inner());
-
-            let mut buffer = Cursor::new(Vec::<u8>::new());
-            rln.get_subtree_root(n, idx_r, &mut buffer).unwrap();
-            let (prev_r, _) = bytes_le_to_fr(&buffer.into_inner());
-
-            let mut buffer = Cursor::new(Vec::<u8>::new());
-            rln.get_subtree_root(n - 1, idx_sr, &mut buffer).unwrap();
-            let (subroot, _) = bytes_le_to_fr(&buffer.into_inner());
-
-            let res = utils_poseidon_hash(&[prev_l, prev_r]);
-            assert_eq!(res, subroot);
-        }
-
         // We double check that the proof computed from public API is correct
-        let root_from_proof = compute_tree_root(
-            &identity_secret_hash,
-            &user_message_limit.into(),
-            &path_elements,
-            &identity_path_index,
-        );
+        let root_from_proof =
+            compute_tree_root(&id_commitment, &path_elements, &identity_path_index, false);
 
         assert_eq!(root, root_from_proof);
     }

semaphore/Cargo.toml

@@ -0,0 +1,50 @@
+[package]
+name = "semaphore-wrapper"
+version = "0.3.0"
+edition = "2021"
+license = "MIT OR Apache-2.0"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[features]
+default = []
+dylib = [ "wasmer/dylib", "wasmer-engine-dylib", "wasmer-compiler-cranelift" ]
+
+[dependencies]
+ark-bn254 = { version = "0.3.0" }
+ark-circom = { git = "https://github.com/gakonst/ark-circom", features=["circom-2"], rev = "35ce5a9" }
+ark-ec = { version = "0.3.0", default-features = false, features = ["parallel"] }
+ark-groth16 = { git = "https://github.com/arkworks-rs/groth16", rev = "765817f", features = ["parallel"] }
+ark-relations = { version = "0.3.0", default-features = false }
+ark-std = { version = "0.3.0", default-features = false, features = ["parallel"] }
+color-eyre = "0.6.1"
+once_cell = "1.8"
+rand = "0.8.4"
+semaphore = { git = "https://github.com/worldcoin/semaphore-rs", rev = "ee658c2"}
+ethers-core = { version = "2.0.8", 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" }
+
+[dev-dependencies]
+rand_chacha = "0.3.1"
+serde_json = "1.0.79"
+
+[build-dependencies]
+color-eyre = "0.6.1"
+wasmer = { version = "2.0" }
+wasmer-engine-dylib = { version = "2.2.1", optional = true }
+wasmer-compiler-cranelift = { version = "3.1.1", optional = true }
+
+[profile.release]
+codegen-units = 1
+lto = true
+panic = "abort"
+opt-level = 3
+
+# Compilation profile for any non-workspace member.
+# Dependencies are optimized, even in a dev build. This improves dev performance
+# while having neglible impact on incremental build times.
+[profile.dev.package."*"]
+opt-level = 3

semaphore/Makefile.toml

@@ -0,0 +1,7 @@
+[tasks.build]
+command = "cargo"
+args = ["build", "--release"]
+
+[tasks.test]
+command = "cargo"
+args = ["test", "--release"]

semaphore/README.md

@@ -0,0 +1,18 @@
+# Semaphore example package
+
+This is basically a wrapper around/copy of
+https://github.com/worldcoin/semaphore-rs to illustrate how e.g. RLN package
+can be structured like.
+
+Goal is also to provide a basic FFI around protocol.rs, which is currently not
+in scope for that project.
+
+See that project for more information.
+
+## Build and Test
+
+To build and test, run the following commands within the module folder
+```bash
+cargo make build
+cargo make test
+```

semaphore/build.rs

@@ -0,0 +1,111 @@
+// Adapted from semaphore-rs/build.rs
+use color_eyre::eyre::{eyre, Result};
+use std::{
+    path::{Component, Path, PathBuf},
+    process::Command,
+};
+
+const ZKEY_FILE: &str = "./vendor/semaphore/build/snark/semaphore_final.zkey";
+const WASM_FILE: &str = "./vendor/semaphore/build/snark/semaphore.wasm";
+
+// See <https://internals.rust-lang.org/t/path-to-lexical-absolute/14940>
+fn absolute(path: &str) -> Result<PathBuf> {
+    let path = Path::new(path);
+    let mut absolute = if path.is_absolute() {
+        PathBuf::new()
+    } else {
+        std::env::current_dir()?
+    };
+    for component in path.components() {
+        match component {
+            Component::CurDir => {}
+            Component::ParentDir => {
+                absolute.pop();
+            }
+            component => absolute.push(component.as_os_str()),
+        }
+    }
+    Ok(absolute)
+}
+
+fn build_circuit() -> Result<()> {
+    println!("cargo:rerun-if-changed=./vendor/semaphore");
+    let run = |cmd: &[&str]| -> Result<()> {
+        // TODO: Use ExitCode::exit_ok() when stable.
+        Command::new(cmd[0])
+            .args(cmd[1..].iter())
+            .current_dir("./vendor/semaphore")
+            .status()?
+            .success()
+            .then_some(())
+            .ok_or(eyre!("procees returned failure"))?;
+        Ok(())
+    };
+
+    // Compute absolute paths
+    let zkey_file = absolute(ZKEY_FILE)?;
+    let wasm_file = absolute(WASM_FILE)?;
+
+    // Build circuits if not exists
+    // TODO: This does not rebuild if the semaphore submodule is changed.
+    // NOTE: This requires npm / nodejs to be installed.
+    if !(zkey_file.exists() && wasm_file.exists()) {
+        run(&["npm", "install"])?;
+        run(&["npm", "exec", "ts-node", "./scripts/compile-circuits.ts"])?;
+    }
+    assert!(zkey_file.exists());
+    assert!(wasm_file.exists());
+
+    // Export generated paths
+    println!("cargo:rustc-env=BUILD_RS_ZKEY_FILE={}", zkey_file.display());
+    println!("cargo:rustc-env=BUILD_RS_WASM_FILE={}", wasm_file.display());
+
+    Ok(())
+}
+
+#[cfg(feature = "dylib")]
+fn build_dylib() -> Result<()> {
+    use enumset::enum_set;
+    use std::{env, str::FromStr};
+    use wasmer::{Module, Store, Target, Triple};
+    use wasmer_compiler_cranelift::Cranelift;
+    use wasmer_engine_dylib::Dylib;
+
+    let wasm_file = absolute(WASM_FILE)?;
+    assert!(wasm_file.exists());
+
+    let out_dir = env::var("OUT_DIR")?;
+    let out_dir = Path::new(&out_dir).to_path_buf();
+    let dylib_file = out_dir.join("semaphore.dylib");
+    println!(
+        "cargo:rustc-env=CIRCUIT_WASM_DYLIB={}",
+        dylib_file.display()
+    );
+
+    if dylib_file.exists() {
+        return Ok(());
+    }
+
+    // Create a WASM engine for the target that can compile
+    let triple = Triple::from_str(&env::var("TARGET")?).map_err(|e| eyre!(e))?;
+    let cpu_features = enum_set!();
+    let target = Target::new(triple, cpu_features);
+    let compiler_config = Cranelift::default();
+    let engine = Dylib::new(compiler_config).target(target).engine();
+
+    // Compile the WASM module
+    let store = Store::new(&engine);
+    let module = Module::from_file(&store, &wasm_file)?;
+    module.serialize_to_file(&dylib_file)?;
+    assert!(dylib_file.exists());
+    println!("cargo:warning=Circuit dylib is in {}", dylib_file.display());
+
+    Ok(())
+}
+
+fn main() -> Result<()> {
+    build_circuit()?;
+    #[cfg(feature = "dylib")]
+    build_dylib()?;
+    Ok(())
+}

semaphore/src/circuit.rs

@@ -0,0 +1,79 @@
+// Adapted from semaphore-rs/src/circuit.rs
+use ark_bn254::{Bn254, Fr};
+use ark_circom::{read_zkey, WitnessCalculator};
+use ark_groth16::ProvingKey;
+use ark_relations::r1cs::ConstraintMatrices;
+use core::include_bytes;
+use once_cell::sync::{Lazy, OnceCell};
+use std::{io::Cursor, sync::Mutex};
+use wasmer::{Module, Store};
+
+#[cfg(feature = "dylib")]
+use std::{env, path::Path};
+#[cfg(feature = "dylib")]
+use wasmer::Dylib;
+
+const ZKEY_BYTES: &[u8] = include_bytes!(env!("BUILD_RS_ZKEY_FILE"));
+
+#[cfg(not(feature = "dylib"))]
+const WASM: &[u8] = include_bytes!(env!("BUILD_RS_WASM_FILE"));
+
+static ZKEY: Lazy<(ProvingKey<Bn254>, ConstraintMatrices<Fr>)> = Lazy::new(|| {
+    let mut reader = Cursor::new(ZKEY_BYTES);
+    read_zkey(&mut reader).expect("zkey should be valid")
+});
+
+static WITNESS_CALCULATOR: OnceCell<Mutex<WitnessCalculator>> = OnceCell::new();
+
+/// Initialize the library.
+#[cfg(feature = "dylib")]
+pub fn initialize(dylib_path: &Path) {
+    WITNESS_CALCULATOR
+        .set(from_dylib(dylib_path))
+        .expect("Failed to initialize witness calculator");
+
+    // Force init of ZKEY
+    Lazy::force(&ZKEY);
+}
+
+#[cfg(feature = "dylib")]
+fn from_dylib(path: &Path) -> Mutex<WitnessCalculator> {
+    let store = Store::new(&Dylib::headless().engine());
+    // The module must be exported using [`Module::serialize`].
+    let module = unsafe {
+        Module::deserialize_from_file(&store, path).expect("Failed to load wasm dylib module")
+    };
+    let result =
+        WitnessCalculator::from_module(module).expect("Failed to create witness calculator");
+    Mutex::new(result)
+}
+
+#[must_use]
+pub fn zkey() -> &'static (ProvingKey<Bn254>, ConstraintMatrices<Fr>) {
+    &ZKEY
+}
+
+#[cfg(feature = "dylib")]
+#[must_use]
+pub fn witness_calculator() -> &'static Mutex<WitnessCalculator> {
+    WITNESS_CALCULATOR.get_or_init(|| {
+        let path = env::var("CIRCUIT_WASM_DYLIB").expect(
+            "Semaphore-rs is not initialized. The library needs to be initialized before use when \
+             build with the `cdylib` feature. You can initialize by calling `initialize` or \
+             seting the `CIRCUIT_WASM_DYLIB` environment variable.",
+        );
+        from_dylib(Path::new(&path))
+    })
+}
+
+#[cfg(not(feature = "dylib"))]
+#[must_use]
+pub fn witness_calculator() -> &'static Mutex<WitnessCalculator> {
+    WITNESS_CALCULATOR.get_or_init(|| {
+        let store = Store::default();
+        let module = Module::from_binary(&store, WASM).expect("wasm should be valid");
+        let result =
+            WitnessCalculator::from_module(module).expect("Failed to create witness calculator");
+        Mutex::new(result)
+    })
+}

semaphore/src/lib.rs

@@ -0,0 +1,7 @@
+#![allow(clippy::multiple_crate_versions)]
+
+pub mod circuit;
+pub mod protocol;
+
+#[cfg(feature = "dylib")]
+pub use circuit::initialize;

semaphore/src/protocol.rs

@@ -0,0 +1,215 @@
+// Adapted from semaphore-rs/src/protocol.rs
+// For illustration purposes only as an example protocol
+
+// Private module
+use crate::circuit::{witness_calculator, zkey};
+
+use ark_bn254::{Bn254, Parameters};
+use ark_circom::CircomReduction;
+use ark_ec::bn::Bn;
+use ark_groth16::{
+    create_proof_with_reduction_and_matrices, prepare_verifying_key, Proof as ArkProof,
+};
+use ark_relations::r1cs::SynthesisError;
+use ark_std::UniformRand;
+use color_eyre::{Report, Result};
+use ethers_core::types::U256;
+use rand::{thread_rng, Rng};
+use semaphore::{
+    identity::Identity,
+    merkle_tree::{self, Branch},
+    poseidon,
+    poseidon_tree::PoseidonHash,
+    Field,
+};
+use serde::{Deserialize, Serialize};
+use std::time::Instant;
+use thiserror::Error;
+
+// Matches the private G1Tup type in ark-circom.
+pub type G1 = (U256, U256);
+
+// Matches the private G2Tup type in ark-circom.
+pub type G2 = ([U256; 2], [U256; 2]);
+
+/// Wrap a proof object so we have serde support
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
+pub struct Proof(G1, G2, G1);
+
+impl From<ArkProof<Bn<Parameters>>> for Proof {
+    fn from(proof: ArkProof<Bn<Parameters>>) -> Self {
+        let proof = ark_circom::ethereum::Proof::from(proof);
+        let (a, b, c) = proof.as_tuple();
+        Self(a, b, c)
+    }
+}
+
+impl From<Proof> for ArkProof<Bn<Parameters>> {
+    fn from(proof: Proof) -> Self {
+        let eth_proof = ark_circom::ethereum::Proof {
+            a: ark_circom::ethereum::G1 {
+                x: proof.0 .0,
+                y: proof.0 .1,
+            },
+            #[rustfmt::skip] // Rustfmt inserts some confusing spaces
+            b: ark_circom::ethereum::G2 {
+                // The order of coefficients is flipped.
+                x: [proof.1.0[1], proof.1.0[0]],
+                y: [proof.1.1[1], proof.1.1[0]],
+            },
+            c: ark_circom::ethereum::G1 {
+                x: proof.2 .0,
+                y: proof.2 .1,
+            },
+        };
+        eth_proof.into()
+    }
+}
+
+/// Helper to merkle proof into a bigint vector
+/// TODO: we should create a From trait for this
+fn merkle_proof_to_vec(proof: &merkle_tree::Proof<PoseidonHash>) -> Vec<Field> {
+    proof
+        .0
+        .iter()
+        .map(|x| match x {
+            Branch::Left(value) | Branch::Right(value) => *value,
+        })
+        .collect()
+}
+
+/// Generates the nullifier hash
+#[must_use]
+pub fn generate_nullifier_hash(identity: &Identity, external_nullifier: Field) -> Field {
+    poseidon::hash2(external_nullifier, identity.nullifier)
+}
+
+#[derive(Error, Debug)]
+pub enum ProofError {
+    #[error("Error reading circuit key: {0}")]
+    CircuitKeyError(#[from] std::io::Error),
+    #[error("Error producing witness: {0}")]
+    WitnessError(Report),
+    #[error("Error producing proof: {0}")]
+    SynthesisError(#[from] SynthesisError),
+    #[error("Error converting public input: {0}")]
+    ToFieldError(#[from] ruint::ToFieldError),
+}
+
+/// Generates a semaphore proof
+///
+/// # Errors
+///
+/// Returns a [`ProofError`] if proving fails.
+pub fn generate_proof(
+    identity: &Identity,
+    merkle_proof: &merkle_tree::Proof<PoseidonHash>,
+    external_nullifier_hash: Field,
+    signal_hash: Field,
+) -> Result<Proof, ProofError> {
+    generate_proof_rng(
+        identity,
+        merkle_proof,
+        external_nullifier_hash,
+        signal_hash,
+        &mut thread_rng(),
+    )
+}
+
+/// Generates a semaphore proof from entropy
+///
+/// # Errors
+///
+/// Returns a [`ProofError`] if proving fails.
+pub fn generate_proof_rng(
+    identity: &Identity,
+    merkle_proof: &merkle_tree::Proof<PoseidonHash>,
+    external_nullifier_hash: Field,
+    signal_hash: Field,
+    rng: &mut impl Rng,
+) -> Result<Proof, ProofError> {
+    generate_proof_rs(
+        identity,
+        merkle_proof,
+        external_nullifier_hash,
+        signal_hash,
+        ark_bn254::Fr::rand(rng),
+        ark_bn254::Fr::rand(rng),
+    )
+}
+
+fn generate_proof_rs(
+    identity: &Identity,
+    merkle_proof: &merkle_tree::Proof<PoseidonHash>,
+    external_nullifier_hash: Field,
+    signal_hash: Field,
+    r: ark_bn254::Fr,
+    s: ark_bn254::Fr,
+) -> Result<Proof, ProofError> {
+    let inputs = [
+        ("identityNullifier", vec![identity.nullifier]),
+        ("identityTrapdoor", vec![identity.trapdoor]),
+        ("treePathIndices", merkle_proof.path_index()),
+        ("treeSiblings", merkle_proof_to_vec(merkle_proof)),
+        ("externalNullifier", vec![external_nullifier_hash]),
+        ("signalHash", vec![signal_hash]),
+    ];
+    let inputs = inputs.into_iter().map(|(name, values)| {
+        (
+            name.to_string(),
+            values.iter().copied().map(Into::into).collect::<Vec<_>>(),
+        )
+    });
+
+    let now = Instant::now();
+
+    let full_assignment = witness_calculator()
+        .lock()
+        .expect("witness_calculator mutex should not get poisoned")
+        .calculate_witness_element::<Bn254, _>(inputs, false)
+        .map_err(ProofError::WitnessError)?;
+
+    println!("witness generation took: {:.2?}", now.elapsed());
+
+    let now = Instant::now();
+    let zkey = zkey();
+    let ark_proof = create_proof_with_reduction_and_matrices::<_, CircomReduction>(
+        &zkey.0,
+        r,
+        s,
+        &zkey.1,
+        zkey.1.num_instance_variables,
+        zkey.1.num_constraints,
+        full_assignment.as_slice(),
+    )?;
+    let proof = ark_proof.into();
+    println!("proof generation took: {:.2?}", now.elapsed());
+
+    Ok(proof)
+}
+
+/// Verifies a given semaphore proof
+///
+/// # Errors
+///
+/// Returns a [`ProofError`] if verifying fails. Verification failure does not
+/// necessarily mean the proof is incorrect.
+pub fn verify_proof(
+    root: Field,
+    nullifier_hash: Field,
+    signal_hash: Field,
+    external_nullifier_hash: Field,
+    proof: &Proof,
+) -> Result<bool, ProofError> {
+    let zkey = zkey();
+    let pvk = prepare_verifying_key(&zkey.0.vk);
+
+    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)
+}

semaphore/tests/protocol.rs

@@ -0,0 +1,115 @@
+#[cfg(test)]
+mod tests {
+    use ark_bn254::Parameters;
+    use ark_ec::bn::Bn;
+    use ark_groth16::Proof as ArkProof;
+    use rand::{Rng, SeedableRng as _};
+    use rand_chacha::ChaChaRng;
+    use semaphore::{hash_to_field, identity::Identity, poseidon_tree::PoseidonTree, Field};
+    use semaphore_wrapper::protocol::{
+        generate_nullifier_hash, generate_proof, generate_proof_rng, verify_proof, Proof,
+    };
+    use serde_json::json;
+
+    #[test]
+    fn test_semaphore() {
+        // generate identity
+        let id = Identity::from_seed(b"secret");
+
+        // generate merkle tree
+        let leaf = Field::from(0);
+        let mut tree = PoseidonTree::new(21, leaf);
+        tree.set(0, id.commitment());
+
+        let merkle_proof = tree.proof(0).expect("proof should exist");
+        let root = tree.root().into();
+
+        // change signal and external_nullifier here
+        let signal_hash = hash_to_field(b"xxx");
+        let external_nullifier_hash = hash_to_field(b"appId");
+
+        let nullifier_hash = generate_nullifier_hash(&id, external_nullifier_hash);
+
+        let proof =
+            generate_proof(&id, &merkle_proof, external_nullifier_hash, signal_hash).unwrap();
+
+        let success = verify_proof(
+            root,
+            nullifier_hash,
+            signal_hash,
+            external_nullifier_hash,
+            &proof,
+        )
+        .unwrap();
+
+        assert!(success);
+    }
+
+    fn arb_proof(seed: u64) -> Proof {
+        // Deterministic randomness for testing
+        let mut rng = ChaChaRng::seed_from_u64(seed);
+
+        // generate identity
+        let seed: [u8; 16] = rng.gen();
+        let id = Identity::from_seed(&seed);
+
+        // generate merkle tree
+        let leaf = Field::from(0);
+        let mut tree = PoseidonTree::new(21, leaf);
+        tree.set(0, id.commitment());
+
+        let merkle_proof = tree.proof(0).expect("proof should exist");
+
+        let external_nullifier: [u8; 16] = rng.gen();
+        let external_nullifier_hash = hash_to_field(&external_nullifier);
+
+        let signal: [u8; 16] = rng.gen();
+        let signal_hash = hash_to_field(&signal);
+
+        generate_proof_rng(
+            &id,
+            &merkle_proof,
+            external_nullifier_hash,
+            signal_hash,
+            &mut rng,
+        )
+        .unwrap()
+    }
+
+    #[test]
+    fn test_proof_cast_roundtrip() {
+        let proof = arb_proof(123);
+        let ark_proof: ArkProof<Bn<Parameters>> = proof.into();
+        let result: Proof = ark_proof.into();
+        assert_eq!(proof, result);
+    }
+
+    #[test]
+    fn test_proof_serialize() {
+        let proof = arb_proof(456);
+        let json = serde_json::to_value(&proof).unwrap();
+        assert_eq!(
+            json,
+            json!([
+                [
+                    "0x249ae469686987ee9368da60dd177a8c42891c02f5760e955e590c79d55cfab2",
+                    "0xf22e25870f49388459d388afb24dcf6ec11bb2d4def1e2ec26d6e42f373aad8"
+                ],
+                [
+                    [
+                        "0x17bd25dbd7436c30ea5b8a3a47aadf11ed646c4b25cc14a84ff8cbe0252ff1f8",
+                        "0x1c140668c56688367416534d57b4a14e5a825efdd5e121a6a2099f6dc4cd277b"
+                    ],
+                    [
+                        "0x26a8524759d969ea0682a092cf7a551697d81962d6c998f543f81e52d83e05e1",
+                        "0x273eb3f796fd1807b9df9c6d769d983e3dabdc61677b75d48bb7691303b2c8dd"
+                    ]
+                ],
+                [
+                    "0x62715c53a0eb4c46dbb5f73f1fd7449b9c63d37c1ece65debc39b472065a90f",
+                    "0x114f7becc66f1cd7a8b01c89db8233622372fc0b6fc037c4313bca41e2377fd9"
+                ]
+            ])
+        );
+    }
+}

utils/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "zerokit_utils"
-version = "0.5.1"
+version = "0.3.2"
 edition = "2021"
 license = "MIT OR Apache-2.0"
 description = "Various utilities for Zerokit"
@@ -13,15 +13,11 @@ bench = false
 
 [dependencies]
 ark-ff = { version = "=0.4.1", default-features = false, features = ["asm"] }
-num-bigint = { version = "=0.4.3", default-features = false, features = [
-    "rand",
-] }
+num-bigint = { version = "=0.4.3", default-features = false, features = ["rand"] }
 color-eyre = "=0.6.2"
-pmtree = { package = "vacp2p_pmtree", version = "=2.0.2", optional = true }
+pmtree = { package = "pmtree", version = "=2.0.0", optional = true}
 sled = "=0.34.7"
 serde = "=1.0.163"
-lazy_static = "1.4.0"
-hex = "0.4"
 
 [dev-dependencies]
 ark-bn254 = "=0.4.0"

utils/benches/merkle_tree_benchmark.rs

@@ -1,7 +1,5 @@
 use criterion::{criterion_group, criterion_main, Criterion};
 use hex_literal::hex;
-use lazy_static::lazy_static;
-use std::{fmt::Display, str::FromStr};
 use tiny_keccak::{Hasher as _, Keccak};
 use zerokit_utils::{
     FullMerkleConfig, FullMerkleTree, Hasher, OptimalMerkleConfig, OptimalMerkleTree,
@@ -11,59 +9,38 @@ use zerokit_utils::{
 #[derive(Clone, Copy, Eq, PartialEq)]
 struct Keccak256;
 
-#[derive(Clone, Copy, Eq, PartialEq, Debug, Default)]
-struct TestFr([u8; 32]);
-
 impl Hasher for Keccak256 {
-    type Fr = TestFr;
+    type Fr = [u8; 32];
 
     fn default_leaf() -> Self::Fr {
-        TestFr([0; 32])
+        [0; 32]
     }
 
     fn hash(inputs: &[Self::Fr]) -> Self::Fr {
         let mut output = [0; 32];
         let mut hasher = Keccak::v256();
         for element in inputs {
-            hasher.update(element.0.as_slice());
+            hasher.update(element);
         }
         hasher.finalize(&mut output);
-        TestFr(output)
+        output
     }
 }
 
-impl Display for TestFr {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{}", String::from_utf8_lossy(self.0.as_slice()))
-    }
-}
-
-impl FromStr for TestFr {
-    type Err = std::string::FromUtf8Error;
-
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
-        Ok(TestFr(s.as_bytes().try_into().unwrap()))
-    }
-}
-
-lazy_static! {
-    static ref LEAVES: [TestFr; 4] = [
-        hex!("0000000000000000000000000000000000000000000000000000000000000001"),
-        hex!("0000000000000000000000000000000000000000000000000000000000000002"),
-        hex!("0000000000000000000000000000000000000000000000000000000000000003"),
-        hex!("0000000000000000000000000000000000000000000000000000000000000004"),
-    ]
-    .map(TestFr);
-}
-
 pub fn optimal_merkle_tree_benchmark(c: &mut Criterion) {
     let mut tree =
-        OptimalMerkleTree::<Keccak256>::new(2, TestFr([0; 32]), OptimalMerkleConfig::default())
-            .unwrap();
+        OptimalMerkleTree::<Keccak256>::new(2, [0; 32], OptimalMerkleConfig::default()).unwrap();
+
+    let leaves = [
+        hex!("0000000000000000000000000000000000000000000000000000000000000001"),
+        hex!("0000000000000000000000000000000000000000000000000000000000000002"),
+        hex!("0000000000000000000000000000000000000000000000000000000000000003"),
+        hex!("0000000000000000000000000000000000000000000000000000000000000004"),
+    ];
 
     c.bench_function("OptimalMerkleTree::set", |b| {
         b.iter(|| {
-            tree.set(0, LEAVES[0]).unwrap();
+            tree.set(0, leaves[0]).unwrap();
         })
     });
 
@@ -75,7 +52,7 @@ pub fn optimal_merkle_tree_benchmark(c: &mut Criterion) {
 
     c.bench_function("OptimalMerkleTree::override_range", |b| {
         b.iter(|| {
-            tree.override_range(0, *LEAVES, [0, 1, 2, 3]).unwrap();
+            tree.override_range(0, leaves, [0, 1, 2, 3]).unwrap();
         })
     });
 
@@ -90,28 +67,22 @@ pub fn optimal_merkle_tree_benchmark(c: &mut Criterion) {
             tree.get(0).unwrap();
         })
     });
-
-    // check intermediate node getter which required additional computation of sub root index
-    c.bench_function("OptimalMerkleTree::get_subtree_root", |b| {
-        b.iter(|| {
-            tree.get_subtree_root(1, 0).unwrap();
-        })
-    });
-
-    c.bench_function("OptimalMerkleTree::get_empty_leaves_indices", |b| {
-        b.iter(|| {
-            tree.get_empty_leaves_indices();
-        })
-    });
 }
 
 pub fn full_merkle_tree_benchmark(c: &mut Criterion) {
     let mut tree =
-        FullMerkleTree::<Keccak256>::new(2, TestFr([0; 32]), FullMerkleConfig::default()).unwrap();
+        FullMerkleTree::<Keccak256>::new(2, [0; 32], FullMerkleConfig::default()).unwrap();
+
+    let leaves = [
+        hex!("0000000000000000000000000000000000000000000000000000000000000001"),
+        hex!("0000000000000000000000000000000000000000000000000000000000000002"),
+        hex!("0000000000000000000000000000000000000000000000000000000000000003"),
+        hex!("0000000000000000000000000000000000000000000000000000000000000004"),
+    ];
 
     c.bench_function("FullMerkleTree::set", |b| {
         b.iter(|| {
-            tree.set(0, LEAVES[0]).unwrap();
+            tree.set(0, leaves[0]).unwrap();
         })
     });
 
@@ -123,7 +94,7 @@ pub fn full_merkle_tree_benchmark(c: &mut Criterion) {
 
     c.bench_function("FullMerkleTree::override_range", |b| {
         b.iter(|| {
-            tree.override_range(0, *LEAVES, [0, 1, 2, 3]).unwrap();
+            tree.override_range(0, leaves, [0, 1, 2, 3]).unwrap();
         })
     });
 
@@ -138,19 +109,6 @@ pub fn full_merkle_tree_benchmark(c: &mut Criterion) {
             tree.get(0).unwrap();
         })
     });
-
-    // check intermediate node getter which required additional computation of sub root index
-    c.bench_function("FullMerkleTree::get_subtree_root", |b| {
-        b.iter(|| {
-            tree.get_subtree_root(1, 0).unwrap();
-        })
-    });
-
-    c.bench_function("FullMerkleTree::get_empty_leaves_indices", |b| {
-        b.iter(|| {
-            tree.get_empty_leaves_indices();
-        })
-    });
 }
 
 criterion_group!(

utils/src/merkle_tree/full_merkle_tree.rs

@@ -8,7 +8,7 @@ use std::{
 };
 
 ////////////////////////////////////////////////////////////
-///// Full Merkle Tree Implementation
+/// Full Merkle Tree Implementation
 ////////////////////////////////////////////////////////////
 
 /// Merkle tree with all leaf and intermediate hashes stored
@@ -26,10 +26,6 @@ pub struct FullMerkleTree<H: Hasher> {
     /// The tree nodes
     nodes: Vec<H::Fr>,
 
-    /// The indices of leaves which are set into zero upto next_index.
-    /// Set to 0 if the leaf is empty and set to 1 in otherwise.
-    cached_leaves_indices: Vec<u8>,
-
     // The next available (i.e., never used) tree index. Equivalently, the number of leaves added to the tree
     // (deletions leave next_index unchanged)
     next_index: usize,
@@ -100,7 +96,6 @@ where
             depth,
             cached_nodes,
             nodes,
-            cached_leaves_indices: vec![0; 1 << depth],
             next_index,
             metadata: Vec::new(),
         })
@@ -121,7 +116,7 @@ where
     }
 
     // Returns the total number of leaves set
-    fn leaves_set(&self) -> usize {
+    fn leaves_set(&mut self) -> usize {
         self.next_index
     }
 
@@ -146,42 +141,6 @@ where
         Ok(self.nodes[self.capacity() + leaf - 1])
     }
 
-    fn get_subtree_root(&self, n: usize, index: usize) -> Result<H::Fr> {
-        if n > self.depth() {
-            return Err(Report::msg("level exceeds depth size"));
-        }
-        if index >= self.capacity() {
-            return Err(Report::msg("index exceeds set size"));
-        }
-        if n == 0 {
-            Ok(self.root())
-        } else if n == self.depth {
-            self.get(index)
-        } else {
-            let mut idx = self.capacity() + index - 1;
-            let mut nd = self.depth;
-            loop {
-                let parent = self.parent(idx).unwrap();
-                nd -= 1;
-                if nd == n {
-                    return Ok(self.nodes[parent]);
-                } else {
-                    idx = parent;
-                    continue;
-                }
-            }
-        }
-    }
-    fn get_empty_leaves_indices(&self) -> Vec<usize> {
-        self.cached_leaves_indices
-            .iter()
-            .take(self.next_index)
-            .enumerate()
-            .filter(|&(_, &v)| v == 0u8)
-            .map(|(idx, _)| idx)
-            .collect()
-    }
-
     // Sets tree nodes, starting from start index
     // Function proper of FullMerkleTree implementation
     fn set_range<I: IntoIterator<Item = FrOf<Self::Hasher>>>(
@@ -199,7 +158,6 @@ where
         }
         hashes.into_iter().for_each(|hash| {
             self.nodes[index + count] = hash;
-            self.cached_leaves_indices[start + count] = 1;
             count += 1;
         });
         if count != 0 {
@@ -209,36 +167,37 @@ where
         Ok(())
     }
 
-    fn override_range<I, J>(&mut self, start: usize, leaves: I, indices: J) -> Result<()>
+    fn override_range<I, J>(&mut self, start: usize, leaves: I, to_remove_indices: J) -> Result<()>
     where
         I: IntoIterator<Item = FrOf<Self::Hasher>>,
         J: IntoIterator<Item = usize>,
     {
-        let indices = indices.into_iter().collect::<Vec<_>>();
-        let min_index = *indices.first().unwrap();
-        let leaves_vec = leaves.into_iter().collect::<Vec<_>>();
-
-        let max_index = start + leaves_vec.len();
-
-        let mut set_values = vec![Self::Hasher::default_leaf(); max_index - min_index];
-
-        for i in min_index..start {
-            if !indices.contains(&i) {
-                let value = self.get(i)?;
-                set_values[i - min_index] = value;
-            }
+        let index = self.capacity() + start - 1;
+        let mut count = 0;
+        let leaves = leaves.into_iter().collect::<Vec<_>>();
+        let to_remove_indices = to_remove_indices.into_iter().collect::<Vec<_>>();
+        // first count number of hashes, and check that they fit in the tree
+        // then insert into the tree
+        if leaves.len() + start - to_remove_indices.len() > self.capacity() {
+            return Err(Report::msg("provided hashes do not fit in the tree"));
         }
 
-        for i in 0..leaves_vec.len() {
-            set_values[start - min_index + i] = leaves_vec[i];
+        // remove leaves
+        for i in &to_remove_indices {
+            self.delete(*i)?;
         }
 
-        for i in indices {
-            self.cached_leaves_indices[i] = 0;
+        // insert new leaves
+        for hash in leaves {
+            self.nodes[index + count] = hash;
+            count += 1;
         }
 
-        self.set_range(start, set_values)
-            .map_err(|e| Report::msg(e.to_string()))
+        if count != 0 {
+            self.update_nodes(index, index + (count - 1))?;
+            self.next_index = max(self.next_index, start + count - to_remove_indices.len());
+        }
+        Ok(())
     }
 
     // Sets a leaf at the next available index
@@ -252,7 +211,6 @@ where
         // We reset the leaf only if we previously set a leaf at that index
         if index < self.next_index {
             self.set(index, H::default_leaf())?;
-            self.cached_leaves_indices[index] = 0;
         }
         Ok(())
     }

utils/src/merkle_tree/merkle_tree.rs

@@ -21,7 +21,7 @@ use color_eyre::Result;
 /// and the hash function used to initialize a Merkle Tree implementation
 pub trait Hasher {
     /// Type of the leaf and tree node
-    type Fr: Clone + Copy + Eq + Default + std::fmt::Debug + std::fmt::Display + FromStr;
+    type Fr: Clone + Copy + Eq;
 
     /// Returns the default tree leaf
     fn default_leaf() -> Self::Fr;
@@ -47,16 +47,14 @@ pub trait ZerokitMerkleTree {
         Self: Sized;
     fn depth(&self) -> usize;
     fn capacity(&self) -> usize;
-    fn leaves_set(&self) -> usize;
+    fn leaves_set(&mut self) -> usize;
     fn root(&self) -> FrOf<Self::Hasher>;
     fn compute_root(&mut self) -> Result<FrOf<Self::Hasher>>;
-    fn get_subtree_root(&self, n: usize, index: usize) -> Result<FrOf<Self::Hasher>>;
     fn set(&mut self, index: usize, leaf: FrOf<Self::Hasher>) -> Result<()>;
     fn set_range<I>(&mut self, start: usize, leaves: I) -> Result<()>
     where
         I: IntoIterator<Item = FrOf<Self::Hasher>>;
     fn get(&self, index: usize) -> Result<FrOf<Self::Hasher>>;
-    fn get_empty_leaves_indices(&self) -> Vec<usize>;
     fn override_range<I, J>(&mut self, start: usize, leaves: I, to_remove_indices: J) -> Result<()>
     where
         I: IntoIterator<Item = FrOf<Self::Hasher>>,

utils/src/merkle_tree/optimal_merkle_tree.rs

@@ -6,7 +6,7 @@ use std::str::FromStr;
 use std::{cmp::max, fmt::Debug};
 
 ////////////////////////////////////////////////////////////
-///// Optimal Merkle Tree Implementation
+/// Optimal Merkle Tree Implementation
 ////////////////////////////////////////////////////////////
 
 /// The Merkle tree structure
@@ -27,10 +27,6 @@ where
     /// The tree nodes
     nodes: HashMap<(usize, usize), H::Fr>,
 
-    /// The indices of leaves which are set into zero upto next_index.
-    /// Set to 0 if the leaf is empty and set to 1 in otherwise.
-    cached_leaves_indices: Vec<u8>,
-
     // The next available (i.e., never used) tree index. Equivalently, the number of leaves added to the tree
     // (deletions leave next_index unchanged)
     next_index: usize,
@@ -55,9 +51,7 @@ impl FromStr for OptimalMerkleConfig {
     }
 }
 
-////////////////////////////////////////////////////////////
-///// Implementations
-////////////////////////////////////////////////////////////
+/// Implementations
 
 impl<H: Hasher> ZerokitMerkleTree for OptimalMerkleTree<H>
 where
@@ -84,7 +78,6 @@ where
             cached_nodes: cached_nodes.clone(),
             depth,
             nodes: HashMap::new(),
-            cached_leaves_indices: vec![0; 1 << depth],
             next_index: 0,
             metadata: Vec::new(),
         })
@@ -105,7 +98,7 @@ where
     }
 
     // Returns the total number of leaves set
-    fn leaves_set(&self) -> usize {
+    fn leaves_set(&mut self) -> usize {
         self.next_index
     }
 
@@ -115,22 +108,6 @@ where
         self.get_node(0, 0)
     }
 
-    fn get_subtree_root(&self, n: usize, index: usize) -> Result<H::Fr> {
-        if n > self.depth() {
-            return Err(Report::msg("level exceeds depth size"));
-        }
-        if index >= self.capacity() {
-            return Err(Report::msg("index exceeds set size"));
-        }
-        if n == 0 {
-            Ok(self.root())
-        } else if n == self.depth {
-            self.get(index)
-        } else {
-            Ok(self.get_node(n, index >> (self.depth - n)))
-        }
-    }
-
     // Sets a leaf at the specified tree index
     fn set(&mut self, index: usize, leaf: H::Fr) -> Result<()> {
         if index >= self.capacity() {
@@ -139,7 +116,6 @@ where
         self.nodes.insert((self.depth, index), leaf);
         self.recalculate_from(index)?;
         self.next_index = max(self.next_index, index + 1);
-        self.cached_leaves_indices[index] = 1;
         Ok(())
     }
 
@@ -151,16 +127,6 @@ where
         Ok(self.get_node(self.depth, index))
     }
 
-    fn get_empty_leaves_indices(&self) -> Vec<usize> {
-        self.cached_leaves_indices
-            .iter()
-            .take(self.next_index)
-            .enumerate()
-            .filter(|&(_, &v)| v == 0u8)
-            .map(|(idx, _)| idx)
-            .collect()
-    }
-
     // Sets multiple leaves from the specified tree index
     fn set_range<I: IntoIterator<Item = H::Fr>>(&mut self, start: usize, leaves: I) -> Result<()> {
         let leaves = leaves.into_iter().collect::<Vec<_>>();
@@ -170,43 +136,40 @@ where
         }
         for (i, leaf) in leaves.iter().enumerate() {
             self.nodes.insert((self.depth, start + i), *leaf);
-            self.cached_leaves_indices[start + i] = 1;
             self.recalculate_from(start + i)?;
         }
         self.next_index = max(self.next_index, start + leaves.len());
         Ok(())
     }
 
-    fn override_range<I, J>(&mut self, start: usize, leaves: I, indices: J) -> Result<()>
+    fn override_range<I, J>(&mut self, start: usize, leaves: I, to_remove_indices: J) -> Result<()>
     where
         I: IntoIterator<Item = FrOf<Self::Hasher>>,
         J: IntoIterator<Item = usize>,
     {
-        let indices = indices.into_iter().collect::<Vec<_>>();
-        let min_index = *indices.first().unwrap();
-        let leaves_vec = leaves.into_iter().collect::<Vec<_>>();
-
-        let max_index = start + leaves_vec.len();
-
-        let mut set_values = vec![Self::Hasher::default_leaf(); max_index - min_index];
-
-        for i in min_index..start {
-            if !indices.contains(&i) {
-                let value = self.get_leaf(i);
-                set_values[i - min_index] = value;
-            }
+        let leaves = leaves.into_iter().collect::<Vec<_>>();
+        let to_remove_indices = to_remove_indices.into_iter().collect::<Vec<_>>();
+        // check if the range is valid
+        if leaves.len() + start - to_remove_indices.len() > self.capacity() {
+            return Err(Report::msg("provided range exceeds set size"));
         }
 
-        for i in 0..leaves_vec.len() {
-            set_values[start - min_index + i] = leaves_vec[i];
+        // remove leaves
+        for i in &to_remove_indices {
+            self.delete(*i)?;
         }
 
-        for i in indices {
-            self.cached_leaves_indices[i] = 0;
+        // add leaves
+        for (i, leaf) in leaves.iter().enumerate() {
+            self.nodes.insert((self.depth, start + i), *leaf);
+            self.recalculate_from(start + i)?;
         }
 
-        self.set_range(start, set_values)
-            .map_err(|e| Report::msg(e.to_string()))
+        self.next_index = max(
+            self.next_index,
+            start + leaves.len() - to_remove_indices.len(),
+        );
+        Ok(())
     }
 
     // Sets a leaf at the next available index
@@ -220,7 +183,6 @@ where
         // We reset the leaf only if we previously set a leaf at that index
         if index < self.next_index {
             self.set(index, H::default_leaf())?;
-            self.cached_leaves_indices[index] = 0;
         }
         Ok(())
     }
@@ -304,7 +266,6 @@ where
             i >>= 1;
             depth -= 1;
             self.nodes.insert((depth, i), h);
-            self.cached_leaves_indices[index] = 1;
             if depth == 0 {
                 break;
             }

utils/tests/merkle_tree.rs

@@ -1,8 +1,7 @@
 // Tests adapted from https://github.com/worldcoin/semaphore-rs/blob/d462a4372f1fd9c27610f2acfe4841fab1d396aa/src/merkle_tree.rs
 #[cfg(test)]
-pub mod test {
+mod test {
     use hex_literal::hex;
-    use std::{fmt::Display, str::FromStr};
     use tiny_keccak::{Hasher as _, Keccak};
     use zerokit_utils::{
         FullMerkleConfig, FullMerkleTree, Hasher, OptimalMerkleConfig, OptimalMerkleTree,
@@ -11,257 +10,74 @@ pub mod test {
     #[derive(Clone, Copy, Eq, PartialEq)]
     struct Keccak256;
 
-    #[derive(Clone, Copy, Eq, PartialEq, Debug, Default)]
-    struct TestFr([u8; 32]);
-
     impl Hasher for Keccak256 {
-        type Fr = TestFr;
+        type Fr = [u8; 32];
 
         fn default_leaf() -> Self::Fr {
-            TestFr([0; 32])
+            [0; 32]
         }
 
         fn hash(inputs: &[Self::Fr]) -> Self::Fr {
             let mut output = [0; 32];
             let mut hasher = Keccak::v256();
             for element in inputs {
-                hasher.update(element.0.as_slice());
+                hasher.update(element);
             }
             hasher.finalize(&mut output);
-            TestFr(output)
+            output
         }
     }
 
-    impl Display for TestFr {
-        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-            write!(f, "{}", hex::encode(self.0.as_slice()))
-        }
-    }
-
-    impl FromStr for TestFr {
-        type Err = std::string::FromUtf8Error;
-
-        fn from_str(s: &str) -> Result<Self, Self::Err> {
-            Ok(TestFr(s.as_bytes().try_into().unwrap()))
-        }
-    }
-
-    impl From<u32> for TestFr {
-        fn from(value: u32) -> Self {
-            let mut bytes: Vec<u8> = vec![0; 28];
-            bytes.extend_from_slice(&value.to_be_bytes());
-            TestFr(bytes.as_slice().try_into().unwrap())
-        }
-    }
-
-    const DEFAULT_DEPTH: usize = 2;
-
-    fn default_full_merkle_tree(depth: usize) -> FullMerkleTree<Keccak256> {
-        FullMerkleTree::<Keccak256>::new(depth, TestFr([0; 32]), FullMerkleConfig::default())
-            .unwrap()
-    }
-
-    fn default_optimal_merkle_tree(depth: usize) -> OptimalMerkleTree<Keccak256> {
-        OptimalMerkleTree::<Keccak256>::new(depth, TestFr([0; 32]), OptimalMerkleConfig::default())
-            .unwrap()
-    }
-
     #[test]
     fn test_root() {
-        let default_tree_root = TestFr(hex!(
-            "b4c11951957c6f8f642c4af61cd6b24640fec6dc7fc607ee8206a99e92410d30"
-        ));
+        let leaves = [
+            hex!("0000000000000000000000000000000000000000000000000000000000000001"),
+            hex!("0000000000000000000000000000000000000000000000000000000000000002"),
+            hex!("0000000000000000000000000000000000000000000000000000000000000003"),
+            hex!("0000000000000000000000000000000000000000000000000000000000000004"),
+        ];
+
+        let default_tree_root =
+            hex!("b4c11951957c6f8f642c4af61cd6b24640fec6dc7fc607ee8206a99e92410d30");
 
         let roots = [
             hex!("c1ba1812ff680ce84c1d5b4f1087eeb08147a4d510f3496b2849df3a73f5af95"),
             hex!("893760ec5b5bee236f29e85aef64f17139c3c1b7ff24ce64eb6315fca0f2485b"),
             hex!("222ff5e0b5877792c2bc1670e2ccd0c2c97cd7bb1672a57d598db05092d3d72c"),
             hex!("a9bb8c3f1f12e9aa903a50c47f314b57610a3ab32f2d463293f58836def38d36"),
-        ]
-        .map(TestFr);
+        ];
 
-        let nof_leaves = 4;
-        let leaves: Vec<TestFr> = (1..=nof_leaves as u32).map(TestFr::from).collect();
-
-        let mut tree = default_full_merkle_tree(DEFAULT_DEPTH);
+        let mut tree =
+            FullMerkleTree::<Keccak256>::new(2, [0; 32], FullMerkleConfig::default()).unwrap();
         assert_eq!(tree.root(), default_tree_root);
-        for i in 0..nof_leaves {
+        for i in 0..leaves.len() {
             tree.set(i, leaves[i]).unwrap();
             assert_eq!(tree.root(), roots[i]);
         }
 
-        let mut tree = default_optimal_merkle_tree(DEFAULT_DEPTH);
+        let mut tree =
+            OptimalMerkleTree::<Keccak256>::new(2, [0; 32], OptimalMerkleConfig::default())
+                .unwrap();
         assert_eq!(tree.root(), default_tree_root);
-        for i in 0..nof_leaves {
+        for i in 0..leaves.len() {
             tree.set(i, leaves[i]).unwrap();
             assert_eq!(tree.root(), roots[i]);
         }
     }
 
-    #[test]
-    fn test_get_empty_leaves_indices() {
-        let depth = 4;
-        let nof_leaves: usize = 1 << (depth - 1);
-        let leaves: Vec<TestFr> = (0..nof_leaves as u32).map(TestFr::from).collect();
-        let leaves_2: Vec<TestFr> = (0u32..2).map(TestFr::from).collect();
-        let leaves_4: Vec<TestFr> = (0u32..4).map(TestFr::from).collect();
-
-        let mut tree_full = default_full_merkle_tree(depth);
-        let _ = tree_full.set_range(0, leaves.clone());
-        assert!(tree_full.get_empty_leaves_indices().is_empty());
-
-        let mut vec_idxs = Vec::new();
-        for i in 0..nof_leaves {
-            vec_idxs.push(i);
-            let _ = tree_full.delete(i);
-            assert_eq!(tree_full.get_empty_leaves_indices(), vec_idxs);
-        }
-
-        for i in (0..nof_leaves).rev() {
-            vec_idxs.pop();
-            let _ = tree_full.set(i, leaves[i]);
-            assert_eq!(tree_full.get_empty_leaves_indices(), vec_idxs);
-        }
-
-        // Check situation when the number of items to insert is less than the number of items to delete
-        tree_full
-            .override_range(0, leaves_2.clone(), [0, 1, 2, 3])
-            .unwrap();
-
-        // check if the indexes for write and delete are the same
-        tree_full
-            .override_range(0, leaves_4.clone(), [0, 1, 2, 3])
-            .unwrap();
-        assert_eq!(tree_full.get_empty_leaves_indices(), vec![]);
-
-        // check if indexes for deletion are before indexes for overwriting
-        tree_full
-            .override_range(4, leaves_4.clone(), [0, 1, 2, 3])
-            .unwrap();
-        assert_eq!(tree_full.get_empty_leaves_indices(), vec![0, 1, 2, 3]);
-
-        // check if the indices for write and delete do not overlap completely
-        tree_full
-            .override_range(2, leaves_4.clone(), [0, 1, 2, 3])
-            .unwrap();
-        assert_eq!(tree_full.get_empty_leaves_indices(), vec![0, 1]);
-
-        //// Optimal Merkle Tree Trest
-
-        let mut tree_opt = default_optimal_merkle_tree(depth);
-        let _ = tree_opt.set_range(0, leaves.clone());
-        assert!(tree_opt.get_empty_leaves_indices().is_empty());
-
-        let mut vec_idxs = Vec::new();
-        for i in 0..nof_leaves {
-            vec_idxs.push(i);
-            let _ = tree_opt.delete(i);
-            assert_eq!(tree_opt.get_empty_leaves_indices(), vec_idxs);
-        }
-        for i in (0..nof_leaves).rev() {
-            vec_idxs.pop();
-            let _ = tree_opt.set(i, leaves[i]);
-            assert_eq!(tree_opt.get_empty_leaves_indices(), vec_idxs);
-        }
-
-        // Check situation when the number of items to insert is less than the number of items to delete
-        tree_opt
-            .override_range(0, leaves_2.clone(), [0, 1, 2, 3])
-            .unwrap();
-
-        // check if the indexes for write and delete are the same
-        tree_opt
-            .override_range(0, leaves_4.clone(), [0, 1, 2, 3])
-            .unwrap();
-        assert_eq!(tree_opt.get_empty_leaves_indices(), vec![]);
-
-        // check if indexes for deletion are before indexes for overwriting
-        tree_opt
-            .override_range(4, leaves_4.clone(), [0, 1, 2, 3])
-            .unwrap();
-        assert_eq!(tree_opt.get_empty_leaves_indices(), vec![0, 1, 2, 3]);
-
-        // check if the indices for write and delete do not overlap completely
-        tree_opt
-            .override_range(2, leaves_4.clone(), [0, 1, 2, 3])
-            .unwrap();
-        assert_eq!(tree_opt.get_empty_leaves_indices(), vec![0, 1]);
-    }
-
-    #[test]
-    fn test_subtree_root() {
-        let depth = 3;
-        let nof_leaves: usize = 6;
-        let leaves: Vec<TestFr> = (0..nof_leaves as u32).map(TestFr::from).collect();
-
-        let mut tree_full = default_optimal_merkle_tree(depth);
-        let _ = tree_full.set_range(0, leaves.iter().cloned());
-
-        for i in 0..nof_leaves {
-            // check leaves
-            assert_eq!(
-                tree_full.get(i).unwrap(),
-                tree_full.get_subtree_root(depth, i).unwrap()
-            );
-
-            // check root
-            assert_eq!(tree_full.root(), tree_full.get_subtree_root(0, i).unwrap());
-        }
-
-        // check intermediate nodes
-        for n in (1..=depth).rev() {
-            for i in (0..(1 << n)).step_by(2) {
-                let idx_l = i * (1 << (depth - n));
-                let idx_r = (i + 1) * (1 << (depth - n));
-                let idx_sr = idx_l;
-
-                let prev_l = tree_full.get_subtree_root(n, idx_l).unwrap();
-                let prev_r = tree_full.get_subtree_root(n, idx_r).unwrap();
-                let subroot = tree_full.get_subtree_root(n - 1, idx_sr).unwrap();
-
-                // check intermediate nodes
-                assert_eq!(Keccak256::hash(&[prev_l, prev_r]), subroot);
-            }
-        }
-
-        let mut tree_opt = default_full_merkle_tree(depth);
-        let _ = tree_opt.set_range(0, leaves.iter().cloned());
-
-        for i in 0..nof_leaves {
-            // check leaves
-            assert_eq!(
-                tree_opt.get(i).unwrap(),
-                tree_opt.get_subtree_root(depth, i).unwrap()
-            );
-            // check root
-            assert_eq!(tree_opt.root(), tree_opt.get_subtree_root(0, i).unwrap());
-        }
-
-        // check intermediate nodes
-        for n in (1..=depth).rev() {
-            for i in (0..(1 << n)).step_by(2) {
-                let idx_l = i * (1 << (depth - n));
-                let idx_r = (i + 1) * (1 << (depth - n));
-                let idx_sr = idx_l;
-
-                let prev_l = tree_opt.get_subtree_root(n, idx_l).unwrap();
-                let prev_r = tree_opt.get_subtree_root(n, idx_r).unwrap();
-                let subroot = tree_opt.get_subtree_root(n - 1, idx_sr).unwrap();
-
-                // check intermediate nodes
-                assert_eq!(Keccak256::hash(&[prev_l, prev_r]), subroot);
-            }
-        }
-    }
-
     #[test]
     fn test_proof() {
-        let nof_leaves = 4;
-        let leaves: Vec<TestFr> = (0..nof_leaves as u32).map(TestFr::from).collect();
+        let leaves = [
+            hex!("0000000000000000000000000000000000000000000000000000000000000001"),
+            hex!("0000000000000000000000000000000000000000000000000000000000000002"),
+            hex!("0000000000000000000000000000000000000000000000000000000000000003"),
+            hex!("0000000000000000000000000000000000000000000000000000000000000004"),
+        ];
 
         // We thest the FullMerkleTree implementation
-        let mut tree = default_full_merkle_tree(DEFAULT_DEPTH);
-        for i in 0..nof_leaves {
+        let mut tree =
+            FullMerkleTree::<Keccak256>::new(2, [0; 32], FullMerkleConfig::default()).unwrap();
+        for i in 0..leaves.len() {
             // We set the leaves
             tree.set(i, leaves[i]).unwrap();
 
@@ -278,12 +94,16 @@ pub mod test {
             assert_eq!(proof.compute_root_from(&leaves[i]), tree.root());
 
             // We check that the proof is not valid for another leaf
-            assert!(!tree.verify(&leaves[(i + 1) % nof_leaves], &proof).unwrap());
+            assert!(!tree
+                .verify(&leaves[(i + 1) % leaves.len()], &proof)
+                .unwrap());
         }
 
         // We test the OptimalMerkleTree implementation
-        let mut tree = default_optimal_merkle_tree(DEFAULT_DEPTH);
-        for i in 0..nof_leaves {
+        let mut tree =
+            OptimalMerkleTree::<Keccak256>::new(2, [0; 32], OptimalMerkleConfig::default())
+                .unwrap();
+        for i in 0..leaves.len() {
             // We set the leaves
             tree.set(i, leaves[i]).unwrap();
 
@@ -300,25 +120,32 @@ pub mod test {
             assert_eq!(proof.compute_root_from(&leaves[i]), tree.root());
 
             // We check that the proof is not valid for another leaf
-            assert!(!tree.verify(&leaves[(i + 1) % nof_leaves], &proof).unwrap());
+            assert!(!tree
+                .verify(&leaves[(i + 1) % leaves.len()], &proof)
+                .unwrap());
         }
     }
 
     #[test]
     fn test_override_range() {
-        let nof_leaves = 4;
-        let leaves: Vec<TestFr> = (0..nof_leaves as u32).map(TestFr::from).collect();
+        let initial_leaves = [
+            hex!("0000000000000000000000000000000000000000000000000000000000000001"),
+            hex!("0000000000000000000000000000000000000000000000000000000000000002"),
+            hex!("0000000000000000000000000000000000000000000000000000000000000003"),
+            hex!("0000000000000000000000000000000000000000000000000000000000000004"),
+        ];
 
-        let mut tree = default_optimal_merkle_tree(DEFAULT_DEPTH);
+        let mut tree =
+            OptimalMerkleTree::<Keccak256>::new(2, [0; 32], OptimalMerkleConfig::default())
+                .unwrap();
 
         // We set the leaves
-        tree.set_range(0, leaves.iter().cloned()).unwrap();
+        tree.set_range(0, initial_leaves.iter().cloned()).unwrap();
 
         let new_leaves = [
             hex!("0000000000000000000000000000000000000000000000000000000000000005"),
             hex!("0000000000000000000000000000000000000000000000000000000000000006"),
-        ]
-        .map(TestFr);
+        ];
 
         let to_delete_indices: [usize; 2] = [0, 1];
 
@@ -331,8 +158,8 @@ pub mod test {
         .unwrap();
 
         // ensure that the leaves are set correctly
-        for (i, &new_leaf) in new_leaves.iter().enumerate() {
-            assert_eq!(tree.get_leaf(i), new_leaf);
+        for i in 0..new_leaves.len() {
+            assert_eq!(tree.get_leaf(i), new_leaves[i]);
         }
     }
 }

utils/tests/poseidon_constants.rs

@@ -25,10 +25,16 @@ mod test {
         input_clean = input_clean.trim().to_string();
 
         if radix == 10 {
-            BigUint::from_str_radix(&input_clean, radix).unwrap().into()
+            BigUint::from_str_radix(&input_clean, radix)
+                .unwrap()
+                .try_into()
+                .unwrap()
         } else {
             input_clean = input_clean.replace("0x", "");
-            BigUint::from_str_radix(&input_clean, radix).unwrap().into()
+            BigUint::from_str_radix(&input_clean, radix)
+                .unwrap()
+                .try_into()
+                .unwrap()
         }
     }
     // The following constants were taken from https://github.com/arnaucube/poseidon-rs/blob/233027d6075a637c29ad84a8a44f5653b81f0410/src/constants.rs
@@ -3494,21 +3500,21 @@ mod test {
     fn load_constants() -> (Vec<Vec<Fr>>, Vec<Vec<Vec<Fr>>>) {
         let (c_str, m_str) = constants();
         let mut c: Vec<Vec<Fr>> = Vec::new();
-        for c_i in c_str {
-            let mut ci: Vec<Fr> = Vec::new();
-            for c_i_j in c_i {
-                let b: Fr = str_to_fr(c_i_j, 10);
-                ci.push(b);
+        for i in 0..c_str.len() {
+            let mut cci: Vec<Fr> = Vec::new();
+            for j in 0..c_str[i].len() {
+                let b: Fr = str_to_fr(c_str[i][j], 10);
+                cci.push(b);
             }
-            c.push(ci);
+            c.push(cci);
         }
         let mut m: Vec<Vec<Vec<Fr>>> = Vec::new();
-        for m_i in m_str {
+        for i in 0..m_str.len() {
             let mut mi: Vec<Vec<Fr>> = Vec::new();
-            for m_i_j in m_i {
+            for j in 0..m_str[i].len() {
                 let mut mij: Vec<Fr> = Vec::new();
-                for m_i_j_k in m_i_j {
-                    let b: Fr = str_to_fr(m_i_j_k, 10);
+                for k in 0..m_str[i][j].len() {
+                    let b: Fr = str_to_fr(m_str[i][j][k], 10);
                     mij.push(b);
                 }
                 mi.push(mij);
@@ -3536,7 +3542,7 @@ mod test {
                 assert_eq!(loaded_m[i], poseidon_parameters[i].m);
             }
         } else {
-            unreachable!();
+            assert!(false);
         }
     }
 }