private static byte[] Scp03_encrypt_key(GPKey kek, GPKey key)
{
try
{
// Pad with random
int n = key.GetLength() % 16 + 1;
byte[] plaintext = new byte[n * 16];
SecureRandom sr = new SecureRandom();
sr.NextBytes(plaintext);
Array.Copy(key.GetValue(), 0, plaintext, 0, key.GetValue().Length);
// encrypt
byte[] cgram = GPCrypto.DoEncrypt_AES_CBC(kek.GetValue(), plaintext);
//Cipher c = Cipher.getInstance(AES_CBC_CIPHER);
//c.init(Cipher.ENCRYPT_MODE, kek.GetEncoded(), null_bytes_16);
//byte[] cgram = c.doFinal(plaintext);
return(cgram);
}
catch (Exception e)
{
throw new Exception("Could not calculate key check value: ", e);
}
}
public GPKeySet GetSessionKeys(int scp, byte[] kdd, params byte[][] args)
{
GPKeySet cardKeys = staticKeys;
if (diversifier != Diversification.NONE)
{
cardKeys = Diversify(staticKeys, kdd, diversifier, scp);
}
System.Diagnostics.Debug.WriteLine(String.Format("card manager keys are diversified from kmc: {0}", Formatting.ByteArrayToHexString(master.GetValue())));
System.Diagnostics.Debug.WriteLine(String.Format("diversified card keys: {0}", cardKeys.ToString()));
GPKeySet sessionKeys;
if (scp == 1)
{
if (args.Length != 2)
{
throw new Exception("SCP01 requires host challenge and card challenge");
}
sessionKeys = DeriveSessionKeysSCP01(cardKeys, args[0], args[1]);
}
else if (scp == 2)
{
if (args.Length != 1)
{
throw new Exception("SCP02 requires sequence");
}
sessionKeys = DeriveSessionKeysSCP02(cardKeys, args[0], false);
}
else if (scp == 3)
{
if (args.Length != 2)
{
throw new Exception("SCP03 requires host challenge and card challenge");
}
sessionKeys = DeriveSessionKeysSCP03(cardKeys, args[0], args[1]);
}
else
{
throw new Exception("Dont know how to handle: " + scp);
}
System.Diagnostics.Debug.WriteLine(String.Format("session keys: {0}", sessionKeys.ToString()));
return(sessionKeys);
}
// SCP03 related
private static byte[] Scp03_mac(GPKey key, byte[] msg, int lengthbits)
{
return(Scp03_mac(key.GetValue(), msg, lengthbits));
}
// GP 2.2.1 Amendment D v 1.1.1
public static byte[] Scp03_kdf(GPKey key, byte constant, byte[] context, int blocklen_bits)
{
return(Scp03_kdf(key.GetValue(), constant, context, blocklen_bits));
}