public bool Verify(byte[] signature, byte[] data, uint160 nonce)
{
byte[] output = new byte[256];
var msg = Utils.Combine(nonce.ToBytes(), data);
Sha512Digest sha512 = new Sha512Digest();
var generator = new Mgf1BytesGenerator(sha512);
generator.Init(new MgfParameters(msg));
generator.GenerateBytes(output, 0, output.Length);
var input = new BigInteger(1, output);
if (input.CompareTo(_Key.Modulus) >= 0)
{
return(false);
}
if (signature.Length > 256)
{
return(false);
}
var signatureInt = new BigInteger(1, signature);
if (signatureInt.CompareTo(_Key.Modulus) >= 0)
{
return(false);
}
var engine = new RsaCoreEngine();
engine.Init(false, _Key);
return(input.Equals(engine.ProcessBlock(signatureInt)));
}
public virtual byte[] ProcessBlock(byte[] inBuf, int inOff, int inLen)
{
if (core == null)
{
throw new InvalidOperationException("RSA engine not initialised");
}
return(core.ConvertOutput(core.ProcessBlock(core.ConvertInput(inBuf, inOff, inLen))));
}
public virtual byte[] ProcessBlock(byte[] inBuf, int inOff, int inLen)
{
if (key == null)
{
throw new InvalidOperationException("RSA engine not initialised");
}
BigInteger bigInteger = core.ConvertInput(inBuf, inOff, inLen);
BigInteger bigInteger4;
if (key is RsaPrivateCrtKeyParameters)
{
RsaPrivateCrtKeyParameters rsaPrivateCrtKeyParameters = (RsaPrivateCrtKeyParameters)key;
BigInteger publicExponent = rsaPrivateCrtKeyParameters.PublicExponent;
if (publicExponent != null)
{
BigInteger modulus = rsaPrivateCrtKeyParameters.Modulus;
BigInteger bigInteger2 = BigIntegers.CreateRandomInRange(BigInteger.One, modulus.Subtract(BigInteger.One), random);
BigInteger input = bigInteger2.ModPow(publicExponent, modulus).Multiply(bigInteger).Mod(modulus);
BigInteger bigInteger3 = core.ProcessBlock(input);
BigInteger val = bigInteger2.ModInverse(modulus);
bigInteger4 = bigInteger3.Multiply(val).Mod(modulus);
if (!bigInteger.Equals(bigInteger4.ModPow(publicExponent, modulus)))
{
throw new InvalidOperationException("RSA engine faulty decryption/signing detected");
}
}
else
{
bigInteger4 = core.ProcessBlock(bigInteger);
}
}
else
{
bigInteger4 = core.ProcessBlock(bigInteger);
}
return(core.ConvertOutput(bigInteger4));
}
internal BigInteger Encrypt(BigInteger data)
{
if (data == null)
{
throw new ArgumentNullException(nameof(data));
}
if (data.CompareTo(_Key.Modulus) >= 0)
{
throw new ArgumentException("input too large for RSA cipher.");
}
RsaCoreEngine engine = new RsaCoreEngine();
engine.Init(true, _Key);
return(engine.ProcessBlock(data));
}
internal BigInteger Decrypt(BigInteger encrypted)
{
if (encrypted == null)
{
throw new ArgumentNullException(nameof(encrypted));
}
if (encrypted.CompareTo(_Key.Modulus) >= 0)
{
throw new DataLengthException("input too large for RSA cipher.");
}
RsaCoreEngine engine = new RsaCoreEngine();
engine.Init(false, _Key);
return(engine.ProcessBlock(encrypted));
}
public byte[] Sign(byte[] data, out uint160 nonce)
{
while (true)
{
byte[] output = new byte[256];
nonce = new uint160(RandomUtils.GetBytes(20));
Sha512Digest sha512 = new Sha512Digest();
var msg = Utils.Combine(nonce.ToBytes(), data);
var generator = new Mgf1BytesGenerator(sha512);
generator.Init(new MgfParameters(msg));
generator.GenerateBytes(output, 0, output.Length);
var input = new BigInteger(1, output);
if (input.CompareTo(_Key.Modulus) >= 0)
{
continue;
}
var engine = new RsaCoreEngine();
engine.Init(true, _Key);
return(engine.ConvertOutput(engine.ProcessBlock(input)));
}
}
