TlsECDHanonKeyExchange
(D)TLS ECDH_anon key exchange (see RFC 4492).
using Org.BouncyCastle.Tls.Crypto;
using System;
using System.IO;
namespace Org.BouncyCastle.Tls
{
public class TlsECDHanonKeyExchange : AbstractTlsKeyExchange
{
protected TlsECConfig m_ecConfig;
protected TlsAgreement m_agreement;
public override bool RequiresServerKeyExchange => true;
private static int CheckKeyExchange(int keyExchange)
{
if (keyExchange == 20)
return keyExchange;
throw new ArgumentException("unsupported key exchange algorithm", "keyExchange");
}
public TlsECDHanonKeyExchange(int keyExchange)
: this(keyExchange, null)
{
}
public TlsECDHanonKeyExchange(int keyExchange, TlsECConfig ecConfig)
: base(CheckKeyExchange(keyExchange))
{
m_ecConfig = ecConfig;
}
public override void SkipServerCredentials()
{
}
public override void ProcessServerCredentials(TlsCredentials serverCredentials)
{
throw new TlsFatalAlert(80);
}
public override void ProcessServerCertificate(Certificate serverCertificate)
{
throw new TlsFatalAlert(10);
}
public override byte[] GenerateServerKeyExchange()
{
MemoryStream memoryStream = new MemoryStream();
TlsEccUtilities.WriteECConfig(m_ecConfig, memoryStream);
m_agreement = m_context.Crypto.CreateECDomain(m_ecConfig).CreateECDH();
GenerateEphemeral(memoryStream);
return memoryStream.ToArray();
}
public override void ProcessServerKeyExchange(Stream input)
{
m_ecConfig = TlsEccUtilities.ReceiveECDHConfig(m_context, input);
byte[] point = TlsUtilities.ReadOpaque8(input, 1);
m_agreement = m_context.Crypto.CreateECDomain(m_ecConfig).CreateECDH();
ProcessEphemeral(point);
}
public override short[] GetClientCertificateTypes()
{
return null;
}
public override void ProcessClientCredentials(TlsCredentials clientCredentials)
{
throw new TlsFatalAlert(80);
}
public override void GenerateClientKeyExchange(Stream output)
{
GenerateEphemeral(output);
}
public override void ProcessClientCertificate(Certificate clientCertificate)
{
throw new TlsFatalAlert(10);
}
public override void ProcessClientKeyExchange(Stream input)
{
byte[] point = TlsUtilities.ReadOpaque8(input, 1);
ProcessEphemeral(point);
}
public override TlsSecret GeneratePreMasterSecret()
{
return m_agreement.CalculateSecret();
}
protected virtual void GenerateEphemeral(Stream output)
{
TlsUtilities.WriteOpaque8(m_agreement.GenerateEphemeral(), output);
}
protected virtual void ProcessEphemeral(byte[] point)
{
TlsEccUtilities.CheckPointEncoding(m_ecConfig.NamedGroup, point);
m_agreement.ReceivePeerValue(point);
}
}
}