SNtruPrimeKemGenerator
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Utilities;
using System;
namespace Org.BouncyCastle.Pqc.Crypto.NtruPrime
{
public class SNtruPrimeKemGenerator : IEncapsulatedSecretGenerator
{
public class SecretWithEncapsulationImpl : ISecretWithEncapsulation, IDisposable
{
private volatile bool hasBeenDestroyed;
private byte[] sessionKey;
private byte[] cipherText;
public SecretWithEncapsulationImpl(byte[] sessionKey, byte[] cipherText)
{
this.sessionKey = sessionKey;
this.cipherText = cipherText;
}
public byte[] GetSecret()
{
CheckDestroyed();
return Arrays.Clone(sessionKey);
}
public byte[] GetEncapsulation()
{
return Arrays.Clone(cipherText);
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool disposing)
{
if (disposing && !hasBeenDestroyed) {
Arrays.Clear(sessionKey);
Arrays.Clear(cipherText);
hasBeenDestroyed = true;
}
}
public bool IsDestroyed()
{
return hasBeenDestroyed;
}
private void CheckDestroyed()
{
if (IsDestroyed())
throw new Exception("data has been destroyed");
}
}
private SecureRandom sr;
public SNtruPrimeKemGenerator(SecureRandom sr)
{
this.sr = sr;
}
public ISecretWithEncapsulation GenerateEncapsulated(AsymmetricKeyParameter recipientKey)
{
SNtruPrimePublicKeyParameters sNtruPrimePublicKeyParameters = (SNtruPrimePublicKeyParameters)recipientKey;
NtruPrimeEngine primeEngine = sNtruPrimePublicKeyParameters.Parameters.PrimeEngine;
byte[] array = new byte[primeEngine.CipherTextSize];
byte[] array2 = new byte[primeEngine.SessionKeySize];
primeEngine.kem_enc(array, array2, sNtruPrimePublicKeyParameters.pubKey, sr);
return new NtruLPRimeKemGenerator.SecretWithEncapsulationImpl(array2, array);
}
}
}