public LatticeND ToLatticeND()
{
LatticeND latticeND = new LatticeND(cols, rows, false);
for (int i = 0; i < cols; i++)
{
latticeND.Vectors[i] = new VectorND(rows);
for (int j = 0; j < rows; j++)
{
latticeND.Vectors[i].values[j] = new BigInteger(mat[j, i]);
}
}
return(latticeND);
}
public LatticeND TransformToLattice(BigInteger sum)
{
LatticeND lattice = new LatticeND(publicKey.dim + 1, publicKey.dim + 1, false);
for (int i = 0; i < publicKey.dim; i++)
{
lattice.Vectors[i] = new VectorND(publicKey.dim + 1);
lattice.Vectors[i].values[i] = 1;
lattice.Vectors[i].values[publicKey.dim] = publicKey.values[i];
}
lattice.Vectors[publicKey.dim] = new VectorND(publicKey.dim + 1);
lattice.Vectors[publicKey.dim].values[publicKey.dim] = sum * (-1);
return(lattice);
}
public void GenerateLattice()
{
lattice = new LatticeND(dim, dim, false);
//Umwandlung der Matrizeneinträge von double zu BigInt und damit Umwandlung der Matrizen zu einem Gitter
VectorND[] privateVectors = new VectorND[dim];
for (int i = 0; i < dim; i++)
{
BigInteger[] privateBigInts = new BigInteger[dim];
for (int j = 0; j < dim; j++)
{
privateBigInts[j] = new BigInteger(privateKeyR[j, i]);
}
privateVectors[i] = new VectorND(privateBigInts);
}
lattice.ReducedVectors = privateVectors;
VectorND[] publicVectors = new VectorND[dim];
for (int i = 0; i < dim; i++)
{
BigInteger[] publicBigInts = new BigInteger[dim];
for (int j = 0; j < dim; j++)
{
publicBigInts[j] = new BigInteger(publicKeyB[j, i]);
}
publicVectors[i] = new VectorND(publicBigInts);
}
lattice.Vectors = publicVectors;
if (transU == null)
{
return;
}
VectorND[] transVectors = new VectorND[dim];
for (int i = 0; i < dim; i++)
{
BigInteger[] transBigInts = new BigInteger[dim];
for (int j = 0; j < dim; j++)
{
transBigInts[j] = new BigInteger(transU[j, i]);
}
transVectors[i] = new VectorND(transBigInts);
}
lattice.UnimodTransVectors = transVectors;
}
public string Cryptanalysis(VectorND cipher, Paragraph paragraph)
{
string messageBinary = "";
foreach (BigInteger value in cipher.values)
{
//BigInteger tempValue = value;
LatticeND lattice = TransformToLattice(value);
//Anmerkung: Der zweite Versuch nach LAGARIAS/ODLYZKO, S.232 funktioniert leider nicht,
//daher wurde dieser Teil auskommentiert
//for (int j = 0; j <= 1; j++)
//{
lattice.LLLReduce();
BigInteger[] vector = FindBinaryVector(lattice.ReducedVectors, value);
// if (vector != null)
// break;
// //Zweiter Versuch
// tempValue = Util.Sum(publicKey.ToList()) - tempValue;
// lattice = TransformToLattice(tempValue);
//}
if (vector == null)
{
throw new Exception();
}
if (paragraph != null)
{
paragraph.Inlines.Add("--------------------\r\n");
paragraph.Inlines.Add(new Bold(new Run(Languages.labelCurrentBlock)));
paragraph.Inlines.Add(" " + value + "\r\n");
paragraph.Inlines.Add(new Bold(new Run(Languages.labelLatticeBasis)));
paragraph.Inlines.Add(" " + lattice.LatticeToString() + "\r\n");
paragraph.Inlines.Add(new Bold(new Run(Languages.labelReducedLatticeBasis)));
paragraph.Inlines.Add(" " + lattice.LatticeReducedToString() + "\r\n");
paragraph.Inlines.Add(new Bold(new Run(Languages.labelFoundVector)));
paragraph.Inlines.Add(" " + new VectorND(vector) + "\r\n");
}
for (int k = 0; k < dim; k++)
{
messageBinary += vector[k];
}
}
int redudandBits = (messageBinary.Length) % maxBitLength;
if (redudandBits > 0)
{
messageBinary = messageBinary.Remove(messageBinary.Length - redudandBits);
}
if (messageBinary.Length >= maxBitLength && messageBinary.Substring(messageBinary.Length - maxBitLength).IndexOf('1') == -1)
{
messageBinary = messageBinary.Remove(messageBinary.Length - maxBitLength);
}
if (paragraph != null)
{
paragraph.Inlines.Add("--------------------\r\n");
paragraph.Inlines.Add(new Bold(new Run(Languages.labelPlainTextBinary)));
paragraph.Inlines.Add(" " + messageBinary + "\r\n");
}
List <byte> bytes = new List <byte>();
for (int i = 0; i < messageBinary.Length; i += maxBitLength)
{
bytes.Add(Convert.ToByte(messageBinary.Substring(i, maxBitLength), 2));
}
string messageUTF8 = Encoding.UTF8.GetString(bytes.ToArray());
if (paragraph != null)
{
paragraph.Inlines.Add(new Bold(new Run(Languages.labelPlainTextUTF8)));
paragraph.Inlines.Add(" " + messageUTF8 + "\r\n");
}
return(messageUTF8);
}