Merge pull request #660 from cryspen/franziskus/ml-kem-fuzzing

Basic ml kem fuzzing

.github/workflows/mlkem.yml

@@ -168,3 +168,37 @@ jobs:
         run: |
           cargo clean
           cargo hack test --each-feature $EXCLUDE_FEATURES --verbose $RUST_TARGET_FLAG
+
+  fuzz:
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - macos-latest # macos-14 m1
+          - ubuntu-latest
+
+    runs-on: ${{ matrix.os }}
+    defaults:
+      run:
+        shell: bash
+        working-directory: libcrux-ml-kem
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: 🛠️ Setup Rust Nightly
+        run: |
+          rustup toolchain install nightly
+          cargo install cargo-fuzz
+
+      - name: 🛠️ Update dependencies
+        run: cargo update
+
+      - name: 🏃🏻‍♀️ Decaps
+        run: CARGO_PROFILE_RELEASE_LTO=false cargo +nightly fuzz run decaps -- -runs=100000
+
+      - name: 🏃🏻‍♀️ Encaps
+        run: CARGO_PROFILE_RELEASE_LTO=false cargo +nightly fuzz run encaps -- -runs=100000
+
+      - name: 🏃🏻‍♀️ KeyGen
+        run: CARGO_PROFILE_RELEASE_LTO=false cargo +nightly fuzz run keygen -- -runs=1000000

Cargo.toml

@@ -8,6 +8,7 @@ members = [
     "benchmarks",
     "fuzz",
     "libcrux-ml-kem",
+    "libcrux-ml-kem/fuzz",
     "libcrux-sha3",
     "libcrux-ml-dsa",
     "libcrux-intrinsics",

libcrux-ml-kem/fuzz/.gitignore

@@ -0,0 +1,4 @@
+target
+corpus
+artifacts
+coverage

libcrux-ml-kem/fuzz/Cargo.toml

@@ -0,0 +1,35 @@
+[package]
+name = "libcrux-ml-kem-fuzz"
+version = "0.0.0"
+publish = false
+edition = "2021"
+
+[package.metadata]
+cargo-fuzz = true
+
+[dependencies]
+libfuzzer-sys = "0.4"
+
+[dependencies.libcrux-ml-kem]
+path = ".."
+
+[[bin]]
+name = "keygen"
+path = "fuzz_targets/keygen.rs"
+test = false
+doc = false
+bench = false
+
+[[bin]]
+name = "encaps"
+path = "fuzz_targets/encaps.rs"
+test = false
+doc = false
+bench = false
+
+[[bin]]
+name = "decaps"
+path = "fuzz_targets/decaps.rs"
+test = false
+doc = false
+bench = false

libcrux-ml-kem/fuzz/fuzz_targets/decaps.rs

@@ -0,0 +1,25 @@
+#![no_main]
+
+use libcrux_ml_kem::{mlkem768, ENCAPS_SEED_SIZE, KEY_GENERATION_SEED_SIZE};
+use libfuzzer_sys::fuzz_target;
+
+fuzz_target!(|data: &[u8]| {
+    if data.len() < KEY_GENERATION_SEED_SIZE + ENCAPS_SEED_SIZE {
+        // Not enough entropy
+        return;
+    }
+
+    let mut randomness = [0u8; KEY_GENERATION_SEED_SIZE];
+    randomness.copy_from_slice(&data[..KEY_GENERATION_SEED_SIZE]);
+
+    let key_pair = mlkem768::generate_key_pair(randomness);
+
+    let mut randomness = [0u8; ENCAPS_SEED_SIZE];
+    randomness.copy_from_slice(
+        &data[KEY_GENERATION_SEED_SIZE..KEY_GENERATION_SEED_SIZE + ENCAPS_SEED_SIZE],
+    );
+
+    let (ct, _ss) = mlkem768::encapsulate(key_pair.public_key(), randomness);
+
+    let _ = core::hint::black_box(mlkem768::decapsulate(key_pair.private_key(), &ct));
+});

libcrux-ml-kem/fuzz/fuzz_targets/encaps.rs

@@ -0,0 +1,23 @@
+#![no_main]
+
+use libcrux_ml_kem::{mlkem768, ENCAPS_SEED_SIZE, KEY_GENERATION_SEED_SIZE};
+use libfuzzer_sys::fuzz_target;
+
+fuzz_target!(|data: &[u8]| {
+    if data.len() < KEY_GENERATION_SEED_SIZE + ENCAPS_SEED_SIZE {
+        // Not enough entropy
+        return;
+    }
+
+    let mut randomness = [0u8; KEY_GENERATION_SEED_SIZE];
+    randomness.copy_from_slice(&data[..KEY_GENERATION_SEED_SIZE]);
+
+    let key_pair = mlkem768::generate_key_pair(randomness);
+
+    let mut randomness = [0u8; ENCAPS_SEED_SIZE];
+    randomness.copy_from_slice(
+        &data[KEY_GENERATION_SEED_SIZE..KEY_GENERATION_SEED_SIZE + ENCAPS_SEED_SIZE],
+    );
+
+    let _ = core::hint::black_box(mlkem768::encapsulate(key_pair.public_key(), randomness));
+});