public static bool Verify(List <List <ECPoint> > PK, MLSAGSignatureType sig)
{
int rows = PK[0].Count;
int cols = PK.Count;
if (cols < 2)
{
throw new Exception("Error! What is c if cols = 1!");
}
int i = 0;
byte[] c_old = new byte[32];
Buffer.BlockCopy(sig.cc, 0, c_old, 0, sig.cc.Length);
List <ECPoint> Li = new List <ECPoint>();
List <byte[]> Ri = new List <byte[]>();
while (i < cols)
{
Li.Clear();
Ri.Clear();
for (int j = 0; j < rows; j++)
{
ECPoint L = ECCurve.Secp256r1.G * sig.ss[i][j] + PK[i][j] * c_old;
byte[] Hi = Crypto.Default.Hash256(PK[i][j].ToString().HexToBytes());
byte[] R = ScalarFunctions.Add(ScalarFunctions.Mul(sig.ss[i][j], Hi), ScalarFunctions.Mul(c_old, sig.II[j]));
Li.Add(L);
Ri.Add(R);
}
c_old = MakeHash(PK[i], Li, Ri);
i = i + 1;
}
return(sig.cc.ToHexString() == c_old.ToHexString());
}
public static MLSAGSignatureType Generate(List <List <ECPoint> > PK, List <byte[]> X, int index)
{
MLSAGSignatureType sig = new MLSAGSignatureType();
int rows = PK[0].Count;
int cols = PK.Count;
#region Initialize
for (int j = 0; j < cols; j++)
{
sig.ss.Add(new List <byte[]>());
}
#endregion
if (cols < 2)
{
throw new Exception("Error! What is c if cols = 1!");
}
List <byte[]> alpha = new List <byte[]>();
List <ECPoint> aG = new List <ECPoint>();
List <byte[]> aHP = new List <byte[]>();
List <ECPoint> Li = new List <ECPoint>();
List <byte[]> Ri = new List <byte[]>();
for (int j = 0; j < rows; j++)
{
byte[] a = SchnorrNonLinkable.GenerateRandomScalar();
alpha.Add(a);
aG.Add(ECCurve.Secp256r1.G * a);
byte[] Hi = Crypto.Default.Hash256(PK[index][j].ToString().HexToBytes());
aHP.Add(ScalarFunctions.Mul(a, Hi));
sig.II.Add(ScalarFunctions.Mul(X[j], Hi));
}
byte[] c_old = MakeHash(PK[index], aG, aHP);
int i = (index + 1) % cols;
if (i == 0)
{
Buffer.BlockCopy(c_old, 0, sig.cc, 0, c_old.Length);
}
while (i != index)
{
for (int j = 0; j < rows; j++)
{
sig.ss[i].Add(SchnorrNonLinkable.GenerateRandomScalar());
}
byte[] c = new byte[32];
Li.Clear();
Ri.Clear();
for (int j = 0; j < rows; j++)
{
ECPoint L = ECCurve.Secp256r1.G * sig.ss[i][j] + PK[i][j] * c_old;
byte[] Hi = Crypto.Default.Hash256(PK[i][j].ToString().HexToBytes());
byte[] R = ScalarFunctions.Add(ScalarFunctions.Mul(sig.ss[i][j], Hi), ScalarFunctions.Mul(c_old, sig.II[j]));
Li.Add(L);
Ri.Add(R);
}
c_old = MakeHash(PK[i], Li, Ri);
i = (i + 1) % cols;
if (i == 0)
{
Buffer.BlockCopy(c_old, 0, sig.cc, 0, c_old.Length);
}
}
for (int j = 0; j < rows; j++)
{
sig.ss[index].Add(ScalarFunctions.MulSub(c_old, X[j], alpha[j]));
}
return(sig);
}
