Trait mls_rs_crypto_traits::DhType

pub trait DhType: Send + Sync {
    type Error: IntoAnyError + Send + Sync;

    // Required methods
    fn dh(
        &self,
        secret_key: &HpkeSecretKey,
        public_key: &HpkePublicKey
    ) -> Result<Vec<u8>, Self::Error>;
    fn generate(&self) -> Result<(HpkeSecretKey, HpkePublicKey), Self::Error>;
    fn to_public(
        &self,
        secret_key: &HpkeSecretKey
    ) -> Result<HpkePublicKey, Self::Error>;
    fn bitmask_for_rejection_sampling(&self) -> Option<u8>;
    fn secret_key_size(&self) -> usize;
    fn public_key_validate(
        &self,
        key: &HpkePublicKey
    ) -> Result<(), Self::Error>;
}

A trait that provides the required DH functions, as in RFC 9180,Section 4.1

Required Associated Types

type Error: IntoAnyError + Send + Sync

Required Methods

fn dh( &self, secret_key: &HpkeSecretKey, public_key: &HpkePublicKey ) -> Result<Vec<u8>, Self::Error>

fn generate(&self) -> Result<(HpkeSecretKey, HpkePublicKey), Self::Error>

Generate a fresh key pair. This is the only place where randomness is used in this module. The function could be implemented in the same way as derive with random ikm, but it could also be implemented directly with a crypto provider like OpenSSL.

fn to_public( &self, secret_key: &HpkeSecretKey ) -> Result<HpkePublicKey, Self::Error>

Outputs the public key corresponding to the given secret key bytes. If the secret key is malformed, the function should return an error.

fn bitmask_for_rejection_sampling(&self) -> Option<u8>

If the output is Some(bitmask), then the Kem::derive function will generate the secret key by rejection sampling over random byte sequences with bitmask applied to the most significant byte.

Typical outputs for ECDH are:

• None for curves 25519 and X448 (no rejection sampling is needed),
• Some(0x01) for curve P-521 (all bits of the first byte except the least significant one are filtered out),
• Some(0xFF)for curves P-256 and P-384 (rejection sampling is needed but no bits need to be filtered).

fn secret_key_size(&self) -> usize

fn public_key_validate(&self, key: &HpkePublicKey) -> Result<(), Self::Error>

Implementors