<PackageReference Include="BouncyCastle.Cryptography" Version="2.7.0-beta.98" />

BcX448

public class BcX448 : TlsAgreement
Support class for X448 using the BC light-weight library.
using Org.BouncyCastle.Math.EC.Rfc7748; using System; namespace Org.BouncyCastle.Tls.Crypto.Impl.BC { public class BcX448 : TlsAgreement { protected readonly BcTlsCrypto m_crypto; protected readonly byte[] m_privateKey = new byte[56]; protected readonly byte[] m_peerPublicKey = new byte[56]; public BcX448(BcTlsCrypto crypto) { m_crypto = crypto; } public virtual byte[] GenerateEphemeral() { X448.GeneratePrivateKey(m_crypto.SecureRandom, m_privateKey); byte[] array = new byte[56]; X448.GeneratePublicKey(m_privateKey, 0, array, 0); return array; } public virtual void ReceivePeerValue(byte[] peerValue) { if (peerValue == null || peerValue.Length != 56) throw new TlsFatalAlert(47); Array.Copy(peerValue, 0, m_peerPublicKey, 0, 56); } public virtual TlsSecret CalculateSecret() { try { byte[] array = new byte[56]; if (!X448.CalculateAgreement(m_privateKey, 0, m_peerPublicKey, 0, array, 0)) throw new TlsFatalAlert(40); return m_crypto.AdoptLocalSecret(array); } finally { Array.Clear(m_privateKey, 0, m_privateKey.Length); Array.Clear(m_peerPublicKey, 0, m_peerPublicKey.Length); } } } }