TlsDheKeyExchange
using Org.BouncyCastle.Tls.Crypto;
using Org.BouncyCastle.Utilities.IO;
using System;
using System.IO;
namespace Org.BouncyCastle.Tls
{
public class TlsDheKeyExchange : AbstractTlsKeyExchange
{
protected TlsDHGroupVerifier m_dhGroupVerifier;
protected TlsDHConfig m_dhConfig;
protected TlsCredentialedSigner m_serverCredentials;
protected TlsCertificate m_serverCertificate;
protected TlsAgreement m_agreement;
public override bool RequiresServerKeyExchange => true;
private static int CheckKeyExchange(int keyExchange)
{
if (keyExchange == 3 || keyExchange == 5)
return keyExchange;
throw new ArgumentException("unsupported key exchange algorithm", "keyExchange");
}
public TlsDheKeyExchange(int keyExchange, TlsDHGroupVerifier dhGroupVerifier)
: this(keyExchange, dhGroupVerifier, null)
{
}
public TlsDheKeyExchange(int keyExchange, TlsDHConfig dhConfig)
: this(keyExchange, null, dhConfig)
{
}
private TlsDheKeyExchange(int keyExchange, TlsDHGroupVerifier dhGroupVerifier, TlsDHConfig dhConfig)
: base(CheckKeyExchange(keyExchange))
{
m_dhGroupVerifier = dhGroupVerifier;
m_dhConfig = dhConfig;
}
public override void SkipServerCredentials()
{
throw new TlsFatalAlert(80);
}
public override void ProcessServerCredentials(TlsCredentials serverCredentials)
{
m_serverCredentials = TlsUtilities.RequireSignerCredentials(serverCredentials);
}
public override void ProcessServerCertificate(Certificate serverCertificate)
{
m_serverCertificate = serverCertificate.GetCertificateAt(0);
}
public override byte[] GenerateServerKeyExchange()
{
DigestInputBuffer digestInputBuffer = new DigestInputBuffer();
TlsDHUtilities.WriteDHConfig(m_dhConfig, digestInputBuffer);
m_agreement = m_context.Crypto.CreateDHDomain(m_dhConfig).CreateDH();
TlsUtilities.WriteOpaque16(m_agreement.GenerateEphemeral(), digestInputBuffer);
TlsUtilities.GenerateServerKeyExchangeSignature(m_context, m_serverCredentials, null, digestInputBuffer);
return digestInputBuffer.ToArray();
}
public override void ProcessServerKeyExchange(Stream input)
{
DigestInputBuffer digestInputBuffer = new DigestInputBuffer();
Stream input2 = new TeeInputStream(input, digestInputBuffer);
m_dhConfig = TlsDHUtilities.ReceiveDHConfig(m_context, m_dhGroupVerifier, input2);
byte[] peerValue = TlsUtilities.ReadOpaque16(input2, 1);
TlsUtilities.VerifyServerKeyExchangeSignature(m_context, input, m_serverCertificate, null, digestInputBuffer);
m_agreement = m_context.Crypto.CreateDHDomain(m_dhConfig).CreateDH();
m_agreement.ReceivePeerValue(peerValue);
}
public override short[] GetClientCertificateTypes()
{
return new short[3] {
2,
64,
1
};
}
public override void ProcessClientCredentials(TlsCredentials clientCredentials)
{
TlsUtilities.RequireSignerCredentials(clientCredentials);
}
public override void GenerateClientKeyExchange(Stream output)
{
TlsUtilities.WriteOpaque16(m_agreement.GenerateEphemeral(), output);
}
public override void ProcessClientKeyExchange(Stream input)
{
m_agreement.ReceivePeerValue(TlsUtilities.ReadOpaque16(input, 1));
}
public override TlsSecret GeneratePreMasterSecret()
{
return m_agreement.CalculateSecret();
}
}
}