Feature/no std

.github/workflows/ci.yml

@@ -16,7 +16,8 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
-        with: { components: rustfmt }
+        with:
+          components: rustfmt
       - run: cargo fmt --all -- --check
 
   # ---------- Tests (independent) ----------
@@ -29,7 +30,14 @@ jobs:
       # Rust toolchain
       - uses: dtolnay/rust-toolchain@stable
 
-      # Cache Cargo deps
+      # --- Pin legacy Noir toolchain (Poseidon2 still in stdlib) -----------
+      - name: Install Noir toolchain 1.0.0-beta.3
+        uses: noir-lang/noirup@v0.1.2
+        with:
+          toolchain: "1.0.0-beta.3"
+      # --------------------------------------------------------------------
+
+      # Cache Cargo dependencies
       - uses: actions/cache@v3
         with:
           path: |
@@ -46,3 +54,11 @@ jobs:
       - name: Run tests
         run: cargo test --verbose
 
+      # ---------- Test alloc feature ----------
+      - name: Test alloc feature
+        run: cargo test alloc --verbose
+
+      # ---------- Test std feature ----------
+      - name: Test std feature
+        run: cargo test std --verbose
+

Cargo.toml

@@ -8,25 +8,45 @@ description = "Rust verifier for UltraHonk proofs"
 repository  = "https://github.com/yugocabrio/ultrahonk-rust-verifier"
 
 [dependencies]
-sha3 = "0.10"
+sha3 = { version = "0.10", default-features = false }
 
-ark-ff = "0.5"
-ark-ec = "0.5"
-ark-serialize = "0.5"
-ark-std = { version = "0.5", features = ["std"] }
-ark-bn254 = { version = "0.5", features = ["std"] }
+ark-ff = { version = "0.5", default-features = false }
+ark-ec = { version = "0.5", default-features = false }
+ark-serialize = { version = "0.5", default-features = false }
+ark-std = { version = "0.5", default-features = false }
+ark-bn254 = { version = "0.5", default-features = false, features = ["curve"] }
 
-anyhow = "1.0"
+serde = { version = "1.0", features = ["derive"], default-features = false, optional = true }
+serde_json = { version = "1.0", default-features = false, features = ["alloc"], optional = true }
+hex = { version = "0.4", default-features = false, features = ["alloc"] }
 
-serde = { version = "1.0", features = ["derive"] }
-serde_json = "1.0"
-hex = "0.4"
+num-bigint = { version = "0.4", default-features = false }
+num-traits = { version = "0.2", default-features = false }
 
-num-bigint = "0.4"
-num-traits = "0.2"
-
-lazy_static = "1.4"
+lazy_static = { version = "1.4", optional = true }
+once_cell = { version = "1.19", default-features = false, features = ["alloc", "race"] }
 
 [features]
-default = []
-trace = []
+default = ["alloc"]
+std = [
+    "sha3/std",
+    "ark-ff/std",
+    "ark-ec/std", 
+    "ark-serialize/std",
+    "ark-std/std",
+    "ark-bn254/std",
+    "serde",
+    "serde_json",
+    "hex/std",
+    "num-bigint/std",
+    "num-traits/std",
+    "lazy_static",
+    "once_cell/std"
+]
+trace = []
+
+alloc = [
+    "serde_json/alloc",
+    "hex/alloc",
+    "once_cell/alloc",
+]

src/debug.rs

@@ -4,6 +4,9 @@ use crate::field::Fr;
 use crate::types::G1Point;
 use ark_ff::{BigInteger256, PrimeField};
 
+#[cfg(not(feature = "std"))]
+use alloc::{format, string::String};
+
 /// trace! macro is a lightweight debug print macro that only outputs when the `trace` feature is enabled.
 /// you can use it like this: cargo test --features trace -- --nocapture / cargo run --features trace
 #[macro_export]

src/field.rs

@@ -4,8 +4,11 @@ use ark_bn254::Fr as ArkFr;
 use ark_ff::BigInteger256;
 use ark_ff::{Field, PrimeField, Zero};
 use ark_serialize::CanonicalSerialize;
+use core::ops::{Add, Mul, Neg, Sub};
 use hex;
-use std::ops::{Add, Mul, Neg, Sub};
+
+#[cfg(not(feature = "std"))]
+use alloc::{borrow::ToOwned, format, string::String};
 
 #[inline(always)]
 fn normalize_hex(s: &str) -> String {
@@ -118,7 +121,7 @@ impl Neg for Fr {
 }
 
 impl CanonicalSerialize for Fr {
-    fn serialize_with_mode<W: std::io::Write>(
+    fn serialize_with_mode<W: ark_serialize::Write>(
         &self,
         mut writer: W,
         _compress: ark_serialize::Compress,

src/lib.rs

@@ -1,4 +1,7 @@
-// src/lib.rs
+#![cfg_attr(not(feature = "std"), no_std)]
+
+#[cfg(not(feature = "std"))]
+extern crate alloc;
 
 pub mod debug;
 pub mod field;

src/relations.rs

@@ -7,7 +7,20 @@
 
 use crate::field::Fr;
 use crate::types::{RelationParameters, Wire};
-use std::ops::Neg;
+use core::ops::Neg;
+
+#[cfg(not(feature = "std"))]
+use alloc::vec;
+
+#[cfg(feature = "std")]
+macro_rules! println {
+    ($($args:tt)*) => { std::println!($($args)*) };
+}
+
+#[cfg(not(feature = "std"))]
+macro_rules! println {
+    ($($args:tt)*) => {};
+}
 
 /// Precomputed NEG_HALF = (p - 1)/2 in BN254 scalar field.
 fn neg_half() -> Fr {

src/shplemini.rs

@@ -11,6 +11,9 @@ use ark_bn254::{Bn254, Fq, Fq2, G1Affine, G1Projective, G2Affine};
 use ark_ec::{pairing::Pairing, CurveGroup, PrimeGroup};
 use ark_ff::{BigInteger, Field, One, PrimeField, Zero};
 
+#[cfg(not(feature = "std"))]
+use alloc::{string::String, vec, vec::Vec};
+
 pub const NUMBER_UNSHIFTED: usize = 35; // = 40 – 5
 pub const NUMBER_SHIFTED: usize = 5; // Final 5 are shifted
 

src/sumcheck.rs

@@ -8,7 +8,17 @@ use crate::{
     types::{Transcript, VerificationKey},
 };
 
-lazy_static::lazy_static! {
+#[cfg(not(feature = "std"))]
+use alloc::{boxed, format, string::String};
+
+#[cfg(feature = "std")]
+use lazy_static::lazy_static;
+
+#[cfg(not(feature = "std"))]
+use once_cell::race::OnceBox;
+
+#[cfg(feature = "std")]
+lazy_static! {
     /// 8-point barycentric coefficients
     static ref BARY: [Fr; 8] = [
         "0x30644e72e131a029b85045b68181585d2833e84879b9709143e1f593efffec51",
@@ -22,6 +32,25 @@ lazy_static::lazy_static! {
     ].map(Fr::from_str);
 }
 
+#[cfg(not(feature = "std"))]
+static BARY_BOX: OnceBox<[Fr; 8]> = OnceBox::new();
+
+#[cfg(not(feature = "std"))]
+fn get_bary() -> &'static [Fr; 8] {
+    BARY_BOX.get_or_init(|| {
+        alloc::boxed::Box::new([
+            Fr::from_str("0x30644e72e131a029b85045b68181585d2833e84879b9709143e1f593efffec51"),
+            Fr::from_str("0x00000000000000000000000000000000000000000000000000000000000002d0"),
+            Fr::from_str("0x30644e72e131a029b85045b68181585d2833e84879b9709143e1f593efffff11"),
+            Fr::from_str("0x0000000000000000000000000000000000000000000000000000000000000090"),
+            Fr::from_str("0x30644e72e131a029b85045b68181585d2833e84879b9709143e1f593efffff71"),
+            Fr::from_str("0x00000000000000000000000000000000000000000000000000000000000000f0"),
+            Fr::from_str("0x30644e72e131a029b85045b68181585d2833e84879b9709143e1f593effffd31"),
+            Fr::from_str("0x00000000000000000000000000000000000000000000000000000000000013b0"),
+        ])
+    })
+}
+
 /// Check if the sum of two univariates equals the target value
 #[inline(always)]
 fn check_round_sum(u: &[Fr], target: Fr) -> bool {
@@ -40,7 +69,12 @@ fn next_target(u: &[Fr], chi: Fr) -> Fr {
     // Σ u_i / (BARY[i] * (χ - i))
     let mut acc = Fr::zero();
     for i in 0..8 {
-        let inv = (BARY[i] * (chi - Fr::from_u64(i as u64))).inverse();
+        #[cfg(feature = "std")]
+        let bary_val = BARY[i];
+        #[cfg(not(feature = "std"))]
+        let bary_val = get_bary()[i];
+
+        let inv = (bary_val * (chi - Fr::from_u64(i as u64))).inverse();
         acc = acc + (u[i] * inv);
     }
 

src/transcript.rs

@@ -11,6 +11,9 @@ use crate::{
 };
 use ark_bn254::G1Affine;
 
+#[cfg(not(feature = "std"))]
+use alloc::vec::Vec;
+
 fn push_point(buf: &mut Vec<u8>, pt: &G1Affine) {
     let (x_lo, x_hi) = fq_to_halves_be(&pt.x);
     let (y_lo, y_hi) = fq_to_halves_be(&pt.y);

src/types.rs

@@ -2,6 +2,9 @@
 use crate::field::Fr;
 use ark_bn254::{Fq, G1Affine};
 
+#[cfg(not(feature = "std"))]
+use alloc::vec::Vec;
+
 /// Number of subrelations in the Ultra Honk protocol.
 pub const NUMBER_OF_SUBRELATIONS: usize = 26;
 pub const CONST_PROOF_SIZE_LOG_N: usize = 28;
@@ -76,7 +79,7 @@ impl G1Point {
     }
 }
 
-/// The verification key structure, matching TS's VerificationKey interface.
+/// The verification key structure
 #[derive(Clone, Debug)]
 pub struct VerificationKey {
     pub circuit_size: u64,

src/utils.rs

@@ -7,8 +7,9 @@ use ark_bn254::Fq;
 use ark_ff::{BigInteger256, PrimeField};
 use num_bigint::BigUint;
 use num_traits::Num;
-use std::fs::File;
-use std::io::Read;
+
+#[cfg(not(feature = "std"))]
+use alloc::{string::String, vec::Vec};
 
 /// Convert 32 bytes into an Fr.
 fn bytes_to_fr(bytes: &[u8; 32]) -> Fr {
@@ -182,15 +183,11 @@ fn combine_fields(low_str: &str, high_str: &str) -> BigUint {
     (high << 136) | low
 }
 
-/// Load a VerificationKey from a JSON file containing an array of hex‐encoded field‐elements.
-pub fn load_vk(path: &str) -> VerificationKey {
-    // Read entire file as string
-    let mut file = File::open(path).expect("VK JSON file not found");
-    let mut data = String::new();
-    file.read_to_string(&mut data).unwrap();
-
+/// Load a VerificationKey from a JSON string containing an array of hex‐encoded field‐elements.
+#[cfg(feature = "serde_json")]
+pub fn load_vk_from_json(json_data: &str) -> VerificationKey {
     // Parse JSON into Vec<String>
-    let vk_fields: Vec<String> = serde_json::from_str(&data).unwrap();
+    let vk_fields: Vec<String> = serde_json::from_str(json_data).unwrap();
     // Ensure we have at least the minimal length
     assert!(
         vk_fields.len() > 127,
@@ -205,7 +202,15 @@ pub fn load_vk(path: &str) -> VerificationKey {
     let public_inputs_size = BigUint::from_str_radix(vk_fields[1].trim_start_matches("0x"), 16)
         .unwrap()
         .to_u64_digits()[0];
-    let log_circuit_size = (circuit_size_u64 as f64).log2() as u64;
+    let log_circuit_size = {
+        let mut n = circuit_size_u64;
+        let mut log = 0;
+        while n > 1 {
+            n >>= 1;
+            log += 1;
+        }
+        log
+    };
 
     // Helper to convert combined BigUint into an Fq
     fn biguint_to_fq(x: BigUint) -> Fq {

src/verifier.rs

@@ -2,21 +2,29 @@
 //! UltraHonk verifier
 
 use crate::{
-    field::Fr,
-    shplemini::verify_shplemini,
-    sumcheck::verify_sumcheck,
-    transcript::generate_transcript,
-    utils::{load_proof, load_vk},
+    field::Fr, shplemini::verify_shplemini, sumcheck::verify_sumcheck,
+    transcript::generate_transcript, utils::load_proof,
 };
 
+#[cfg(feature = "serde_json")]
+use crate::utils::load_vk_from_json;
+
+#[cfg(not(feature = "std"))]
+use alloc::{format, string::String, vec::Vec};
+
 pub struct UltraHonkVerifier {
     vk: crate::types::VerificationKey,
 }
 
 impl UltraHonkVerifier {
-    pub fn new(vk_path: &str) -> Self {
+    pub fn new_with_vk(vk: crate::types::VerificationKey) -> Self {
+        Self { vk }
+    }
+
+    #[cfg(feature = "serde_json")]
+    pub fn new_from_json(json_data: &str) -> Self {
         Self {
-            vk: load_vk(vk_path),
+            vk: load_vk_from_json(json_data),
         }
     }
 

tests/verifier_test.rs

@@ -7,8 +7,8 @@ fn run(dir: &str) -> Result<(), String> {
     let proof_buf = fs::read(path.join("proof")).map_err(|e| e.to_string())?;
     let (pub_inputs, proof_bytes) = load_proof_and_public_inputs(&proof_buf);
 
-    let vk_path = path.join("vk_fields.json");
-    let verifier = UltraHonkVerifier::new(vk_path.to_str().unwrap());
+    let vk_json = fs::read_to_string(path.join("vk_fields.json")).map_err(|e| e.to_string())?;
+    let verifier = UltraHonkVerifier::new_from_json(&vk_json);
 
     let pub_inputs_bytes: Vec<Vec<u8>> =
         pub_inputs.iter().map(|fr| fr.to_bytes().to_vec()).collect();