BcX448
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()
{
m_crypto.SecureRandom.NextBytes(m_privateKey);
byte[] array = new byte[56];
X448.ScalarMultBase(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);
}
}
}
}