add kyber512 from libcrux

ciphers/Cargo.toml

@@ -13,6 +13,7 @@ readme = "readme.md"
 experiment_libcrux = [
     "dep:libcrux",
     "dep:libcrux-chacha20poly1305",
+    "dep:libcrux-ml-kem",
 ]
 
 [dependencies]
@@ -28,7 +29,10 @@ zeroize = { workspace = true }
 chacha20poly1305 = { workspace = true }
 blake2 = { workspace = true }
 libcrux = { workspace = true, optional = true }
-sha3 = {workspace = true}
 libcrux-chacha20poly1305 = { workspace = true, optional = true }
+libcrux-ml-kem = { workspace = true, optional = true, features = ["kyber"] }
+sha3 = { workspace = true }
+rand = { workspace = true }
+
 [dev-dependencies]
 rand = { workspace = true }

ciphers/src/subtle/libcrux/kyber512.rs

@@ -0,0 +1,62 @@
+use libcrux_ml_kem::kyber512;
+
+use rand::RngCore;
+
+use rosenpass_cipher_traits::algorithms::kem_kyber512::*;
+use rosenpass_cipher_traits::primitives::{Kem, KemError};
+
+pub struct Kyber512;
+
+impl Kem<SK_LEN, PK_LEN, CT_LEN, SHK_LEN> for Kyber512 {
+    fn keygen(&self, sk: &mut [u8; SK_LEN], pk: &mut [u8; PK_LEN]) -> Result<(), KemError> {
+        let mut randomness = [0u8; libcrux_ml_kem::KEY_GENERATION_SEED_SIZE];
+        rand::thread_rng().fill_bytes(&mut randomness);
+
+        let key_pair = kyber512::generate_key_pair(randomness);
+
+        let new_sk: &[u8; SK_LEN] = key_pair.sk();
+        let new_pk: &[u8; PK_LEN] = key_pair.pk();
+
+        sk.clone_from_slice(new_sk);
+        pk.clone_from_slice(new_pk);
+
+        Ok(())
+    }
+
+    fn encaps(
+        &self,
+        shk: &mut [u8; SHK_LEN],
+        ct: &mut [u8; CT_LEN],
+        pk: &[u8; PK_LEN],
+    ) -> Result<(), KemError> {
+        let mut randomness = [0u8; libcrux_ml_kem::SHARED_SECRET_SIZE];
+        rand::thread_rng().fill_bytes(&mut randomness);
+
+        let (new_ct, new_shk) = kyber512::encapsulate(&pk.into(), randomness);
+        let new_ct: &[u8; CT_LEN] = new_ct.as_slice();
+
+        shk.clone_from_slice(&new_shk);
+        ct.clone_from_slice(new_ct);
+
+        Ok(())
+    }
+
+    fn decaps(
+        &self,
+        shk: &mut [u8; SHK_LEN],
+        sk: &[u8; SK_LEN],
+        ct: &[u8; CT_LEN],
+    ) -> Result<(), KemError> {
+        let new_shk: [u8; SHK_LEN] = kyber512::decapsulate(&sk.into(), &ct.into());
+        shk.clone_from(&new_shk);
+        Ok(())
+    }
+}
+
+impl Default for Kyber512 {
+    fn default() -> Self {
+        Self
+    }
+}
+
+impl KemKyber512 for Kyber512 {}

ciphers/src/subtle/libcrux/mod.rs

@@ -1,3 +1,4 @@
 //! Implementations backed by libcrux, a verified crypto library
 
 pub mod chacha20poly1305_ietf;
+pub mod kyber512;