public SenderKeyMessage(UInt32 keyId, UInt32 iteration, byte[] ciphertext, ECPrivateKey signatureKey)
{
byte[] version = { ByteUtil.IntsToByteHighAndLow(CURRENT_VERSION, CURRENT_VERSION) };
var messageObj = new WhisperProtos.SenderKeyMessage {
id = (uint)keyId,
iteration = (uint)iteration,
ciphertext = ciphertext,
};
byte[] message;
using(var stream = new MemoryStream())
{
Serializer.Serialize<WhisperProtos.SenderKeyMessage>(stream, messageObj);
message = stream.ToArray();
}
byte[] signature = GetSignature(signatureKey, ByteUtil.Combine(version, message));
_serialized = ByteUtil.Combine(version, message, signature);
KeyId = keyId;
Iteration = iteration;
CipherText = ciphertext;
}
public static byte[] CalculateSignature(ECPrivateKey privateKey, byte[] message)
{
if (privateKey.GetKeyType () == DJB_TYPE) {
var sign = Sodium.SecretKeyAuth.SignHmacSha256 (message, privateKey.Serialize ());
return sign;
} else {
throw new Exception ("Unknown type");
}
}
public static byte[] CalculateAgreement(ECPublicKey publicKey, ECPrivateKey privateKey)
{
if (publicKey.GetKeyType () != privateKey.GetKeyType ()) {
throw new Exception ("Public and private keys must be of the same type!");
}
if (publicKey.GetKeyType () == DJB_TYPE) {
var sK = privateKey.Serialize ();
var typedPK = publicKey.Serialize ();
var pK = new byte[typedPK.Length - 1];
for (int i = 1; i < typedPK.Length; i++) {
pK [i - 1] = typedPK [i];
}
var shared = Sodium.ScalarMult.Mult (sK, pK);
return shared;
} else {
throw new Exception ("Unknown type");
}
}
private byte[] GetSignature(ECPrivateKey signatureKey, byte[] serialized)
{
try
{
return Curve.CalculateSignature(signatureKey, serialized);
}
catch(Exception e)
{
throw new InvalidOperationException("Assertion error: " + e);
}
}
public ECKeyPair(ECPrivateKey privateKey, ECPublicKey publicKey)
{
PrivateKey = privateKey;
PublicKey = publicKey;
}
public IdentityKeyPair(IdentityKey publicKey, ECPrivateKey privateKey)
{
PublicKey = publicKey;
PrivateKey = privateKey;
}
