public DiffieHellmanKeyExchange(TlsContext ctx)
{
this.protocol = ctx.NegotiatedProtocol;
switch (protocol)
{
case TlsProtocolCode.Tls12:
Signature = new SignatureTls12(ctx.Session.ServerSignatureAlgorithm);
break;
case TlsProtocolCode.Tls10:
Signature = new SignatureTls10();
break;
case TlsProtocolCode.Tls11:
Signature = new SignatureTls11();
break;
default:
throw new NotSupportedException();
}
dh = new DiffieHellmanManaged();
Y = dh.CreateKeyExchange();
var dhparams = dh.ExportParameters(true);
P = dhparams.P;
G = dhparams.G;
using (var buffer = CreateParameterBuffer(ctx.HandshakeParameters))
Signature.Create(buffer, ctx.Configuration.PrivateKey);
}
public static void Main(string[] args)
{
// create a new DH instance
DiffieHellman dh1 = new DiffieHellmanManaged();
// export the public parameters of the first DH instance
DHParameters dhp = dh1.ExportParameters(false);
// create a second DH instance and initialize it with the public parameters of the first instance
DiffieHellman dh2 = new DiffieHellmanManaged(dhp.P, dhp.G, 160);
// generate the public key of the first DH instance
byte[] ke1 = dh1.CreateKeyExchange();
// generate the public key of the second DH instance
byte[] ke2 = dh2.CreateKeyExchange();
// let the first DH instance compute the shared secret using the second DH public key
byte[] dh1k = dh1.DecryptKeyExchange(ke2);
// let the second DH instance compute the shared secret using the first DH public key
byte[] dh2k = dh2.DecryptKeyExchange(ke1);
// print both shared secrets to verify they are the same
Console.WriteLine("Computed secret of instance 1:");
PrintBytes(dh1k);
Console.WriteLine("\r\nComputed secret of instance 2:");
PrintBytes(dh2k);
Console.WriteLine("\r\nPress ENTER to continue...");
Console.ReadLine();
}
public override KeyPair GenerateKeyPair()
{
DiffieHellmanManaged dh = new DiffieHellmanManaged(pspec.P.GetBytes(), pspec.G.GetBytes(), 0);
DHParameters dhpars = dh.ExportParameters(true);
BigInteger y = new BigInteger(dh.CreateKeyExchange());
return(new KeyPair(new DHPrivateKey(dhpars), new DHPublicKey(y)));
}
public static DHKeyPair GenerateKeyPair(int keysize)
{
DiffieHellman dh = new DiffieHellmanManaged(_prime, new byte[] { 0x02 }, keysize);
DHParameters privateKey = dh.ExportParameters(true);
return(new DHKeyPair(
new DHPrivateKey(privateKey),
new DHPublicKey(dh.CreateKeyExchange())));
}
void CreateServer(TlsContext ctx)
{
dh = new DiffieHellmanManaged();
Y = dh.CreateKeyExchange();
var dhparams = dh.ExportParameters(true);
P = dhparams.P;
G = dhparams.G;
using (var buffer = CreateParameterBuffer(ctx.HandshakeParameters))
Signature = SignatureHelper.CreateSignature(SignatureAlgorithm, buffer, ctx.Configuration.PrivateKey);
}
void InitDiffieHellman(NativeOpenSslProtocol protocol)
{
var dh = new DiffieHellmanManaged();
var dhparams = dh.ExportParameters(true);
openssl.SetDhParams(dhparams.P, dhparams.G);
// Optional: this is OpenSsl's default value.
if (protocol == NativeOpenSslProtocol.TLS12)
{
openssl.SetNamedCurve("prime256v1");
}
}
public static void Main(string[] args)
{
DiffieHellman diffieHellman = new DiffieHellmanManaged();
DHParameters dHParameters = diffieHellman.ExportParameters(includePrivate: false);
DiffieHellman diffieHellman2 = new DiffieHellmanManaged(dHParameters.P, dHParameters.G, 160);
byte[] keyEx = diffieHellman.CreateKeyExchange();
byte[] keyEx2 = diffieHellman2.CreateKeyExchange();
byte[] bytes = diffieHellman.DecryptKeyExchange(keyEx2);
byte[] bytes2 = diffieHellman2.DecryptKeyExchange(keyEx);
Console.WriteLine("Computed secret of instance 1:");
PrintBytes(bytes);
Console.WriteLine("\r\nComputed secret of instance 2:");
PrintBytes(bytes2);
Console.WriteLine("\r\nPress ENTER to continue...");
Console.ReadLine();
}
public void KeyExchange()
{
// create a new DH instance
DiffieHellman dh1 = new DiffieHellmanManaged();
// export the public parameters of the first DH instance
DHParameters dhp = dh1.ExportParameters(false);
// create a second DH instance and initialize it with the public parameters of the first instance
DiffieHellman dh2 = new DiffieHellmanManaged(dhp.P, dhp.G, 160);
// generate the public key of the first DH instance
byte[] ke1 = dh1.CreateKeyExchange();
// generate the public key of the second DH instance
byte[] ke2 = dh2.CreateKeyExchange();
// let the first DH instance compute the shared secret using the second DH public key
byte[] dh1k = dh1.DecryptKeyExchange(ke2);
// let the second DH instance compute the shared secret using the first DH public key
byte[] dh2k = dh2.DecryptKeyExchange(ke1);
// both shared secrets are the same
AssertEquals("Shared Secret", dh1k, dh2k);
}
