private void testMutualVerification(Srp6GroupParameters group)
{
byte[] I = Encoding.UTF8.GetBytes("username");
byte[] P = Encoding.UTF8.GetBytes("password");
byte[] s = new byte[16];
random.NextBytes(s);
Srp6VerifierGenerator gen = new Srp6VerifierGenerator();
gen.Init(group, new Sha256Digest());
BigInteger v = gen.GenerateVerifier(s, I, P);
Srp6Client client = new Srp6Client();
client.Init(group, new Sha256Digest(), random);
Srp6Server server = new Srp6Server();
server.Init(group, v, new Sha256Digest(), random);
BigInteger A = client.GenerateClientCredentials(s, I, P);
BigInteger B = server.GenerateServerCredentials();
BigInteger clientS = client.CalculateSecret(B);
BigInteger serverS = server.CalculateSecret(A);
if (!clientS.Equals(serverS))
{
Fail("SRP agreement failed - client/server calculated different secrets");
}
}
private void testClientCatchesBadB(Srp6GroupParameters group)
{
byte[] I = Encoding.UTF8.GetBytes("username");
byte[] P = Encoding.UTF8.GetBytes("password");
byte[] s = new byte[16];
random.NextBytes(s);
Srp6Client client = new Srp6Client();
client.Init(group, new Sha256Digest(), random);
client.GenerateClientCredentials(s, I, P);
try
{
client.CalculateSecret(BigInteger.Zero);
Fail("Client failed to detect invalid value for 'B'");
}
catch (CryptoException)
{
// Expected
}
try
{
client.CalculateSecret(group.N);
Fail("Client failed to detect invalid value for 'B'");
}
catch (CryptoException)
{
// Expected
}
}
public static BigInteger Srp6Response(string username, byte[] password, byte[] salt, BigInteger B, out BigInteger token)
{
var random = new SecureRandom(new CryptoApiRandomGenerator());
var I = Encoding.UTF8.GetBytes(username);
var p = FromInput(password, salt);
var client = new Srp6Client();
client.Init(GroupParameters, new Sha256Digest(), random);
token = client.GenerateClientCredentials(salt, I, p);
client.CalculateSecret(B);
return(client.CalculateClientEvidenceMessage());
}
public override void ProcessServerKeyExchange(Stream input)
{
SecurityParameters securityParameters = mContext.SecurityParameters;
SignerInputBuffer signerInputBuffer = null;
Stream input2 = input;
if (mTlsSigner != null)
{
signerInputBuffer = new SignerInputBuffer();
input2 = (Stream)(object)new TeeInputStream(input, (Stream)(object)signerInputBuffer);
}
ServerSrpParams serverSrpParams = ServerSrpParams.Parse(input2);
if (signerInputBuffer != null)
{
DigitallySigned digitallySigned = ParseSignature(input);
ISigner signer = InitVerifyer(mTlsSigner, digitallySigned.Algorithm, securityParameters);
signerInputBuffer.UpdateSigner(signer);
if (!signer.VerifySignature(digitallySigned.Signature))
{
throw new TlsFatalAlert(51);
}
}
mSrpGroup = new Srp6GroupParameters(serverSrpParams.N, serverSrpParams.G);
if (!mGroupVerifier.Accept(mSrpGroup))
{
throw new TlsFatalAlert(71);
}
mSrpSalt = serverSrpParams.S;
try
{
mSrpPeerCredentials = Srp6Utilities.ValidatePublicValue(mSrpGroup.N, serverSrpParams.B);
}
catch (CryptoException alertCause)
{
throw new TlsFatalAlert(47, alertCause);
}
mSrpClient.Init(mSrpGroup, TlsUtilities.CreateHash(2), mContext.SecureRandom);
}
