/// <summary>
/// Initialize this class for CCA2 MPKCS
/// </summary>
///
/// <param name="N">Length of the code</param>
/// <param name="K">The dimension of the code</param>
/// <param name="Gf">The finite field <c>GF(2^m)</c></param>
/// <param name="Gp">The irreducible Goppa polynomial</param>
/// <param name="P">The permutation</param>
/// <param name="H">The canonical check matrix</param>
/// <param name="QInv">The matrix used to compute square roots in <c>(GF(2^m))^t</c></param>
internal MPKCPrivateKey(int N, int K, GF2mField Gf, PolynomialGF2mSmallM Gp, Permutation P, GF2Matrix H, PolynomialGF2mSmallM[] QInv)
{
_N = N;
_K = K;
_gField = Gf;
_goppaPoly = Gp;
_P1 = P;
_H = H;
_qInv = QInv;
}
/// <summary>
/// Initialize this class CCA2 MPKCS using encoded byte arrays
/// </summary>
///
/// <param name="N">Length of the code</param>
/// <param name="K">The dimension of the code</param>
/// <param name="Gf">Encoded field polynomial defining the finite field <c>GF(2^m)</c></param>
/// <param name="Gp">Encoded irreducible Goppa polynomial</param>
/// <param name="P">The encoded permutation</param>
/// <param name="H">Encoded canonical check matrix</param>
/// <param name="QInv">The encoded matrix used to compute square roots in <c>(GF(2^m))^t</c></param>
public MPKCPrivateKey(int N, int K, byte[] Gf, byte[] Gp, byte[] P, byte[] H, byte[][] QInv)
{
_N = N;
_K = K;
_gField = new GF2mField(Gf);
_goppaPoly = new PolynomialGF2mSmallM(_gField, Gp);
_P1 = new Permutation(P);
_H = new GF2Matrix(H);
_qInv = new PolynomialGF2mSmallM[QInv.Length];
for (int i = 0; i < QInv.Length; i++)
_qInv[i] = new PolynomialGF2mSmallM(_gField, QInv[i]);
}
/// <summary>
/// Multiply this vector with a permutation
/// </summary>
///
/// <param name="P">he permutation</param>
///
/// <returns>Returns <c>this*p = p*this</c></returns>
public override Vector Multiply(Permutation P)
{
int[] pVec = P.GetVector();
if (Length != pVec.Length)
throw new ArithmeticException("permutation size and vector size mismatch");
int[] result = new int[Length];
for (int i = 0; i < pVec.Length; i++)
result[i] = _vector[pVec[i]];
return new GF2mVector(_field, result);
}
/// <summary>
/// Compute the product of this permutation and another permutation
/// </summary>
///
/// <param name="p">The other permutation</param>
///
/// <returns>Returns <c>this * P</c></returns>
public Permutation RightMultiply(Permutation p)
{
if (p._perm.Length != _perm.Length)
throw new ArgumentException("length mismatch");
Permutation result = new Permutation(_perm.Length);
for (int i = _perm.Length - 1; i >= 0; i--)
result._perm[i] = _perm[p._perm[i]];
return result;
}
/// <summary>
/// Compute the inverse permutation <c>P pow -1</c>
/// </summary>
///
/// <returns>Returns <c>this pow -1</c></returns>
public Permutation ComputeInverse()
{
Permutation result = new Permutation(_perm.Length);
for (int i = _perm.Length - 1; i >= 0; i--)
result._perm[_perm[i]] = i;
return result;
}
//3
/// <summary>
/// Compute the product of this matrix and a permutation matrix which is generated from an n-permutation
/// </summary>
///
/// <param name="P">The permutation</param>
///
/// <returns>Returns GF2Matrix <c>this*P</c></returns>
public override Matrix RightMultiply(Permutation P)
{
int[] pVec = P.GetVector();
if (pVec.Length != ColumnCount)
throw new ArithmeticException("GF2Matrix: Length mismatch!");
GF2Matrix result = new GF2Matrix(RowCount, ColumnCount);
for (int i = ColumnCount - 1; i >= 0; i--)
{
int q = IntUtils.URShift(i, 5);
int r = i & 0x1f;
int pq = IntUtils.URShift(pVec[i], 5);
int pr = pVec[i] & 0x1f;
for (int j = RowCount - 1; j >= 0; j--)
result._matrix[j][q] |= ((IntUtils.URShift(_matrix[j][pq], pr)) & 1) << r;
}
return result;
}
/// <summary>
/// Compute the product of a permutation matrix (which is generated from an n-permutation) and this matrix.
/// </summary>
///
/// <param name="P">The permutation</param>
///
/// <returns>Returns GF2Matrix <c>P*this</c></returns>
public Matrix LeftMultiply(Permutation P)
{
int[] pVec = P.GetVector();
if (pVec.Length != RowCount)
throw new ArithmeticException("GF2Matrix: length mismatch!");
int[][] result = new int[RowCount][];
for (int i = RowCount - 1; i >= 0; i--)
result[i] = IntUtils.DeepCopy(_matrix[pVec[i]]);
return new GF2Matrix(RowCount, result);
}
/// <summary>
/// Create a nxn random regular matrix and its inverse
/// </summary>
///
/// <param name="N">Number of rows (and columns)</param>
/// <param name="SecRnd">Source of randomness</param>
/// <returns>The created random regular matrix and its inverse</returns>
public static GF2Matrix[] CreateRandomRegularMatrixAndItsInverse(int N, IRandom SecRnd)
{
GF2Matrix[] result = new GF2Matrix[2];
// First part: create regular matrix
int length = (N + 31) >> 5;
GF2Matrix lm = new GF2Matrix(N, Matrix.MATRIX_TYPE_RANDOM_LT, SecRnd);
GF2Matrix um = new GF2Matrix(N, Matrix.MATRIX_TYPE_RANDOM_UT, SecRnd);
GF2Matrix rm = (GF2Matrix)lm.RightMultiply(um);
Permutation p = new Permutation(N, SecRnd);
int[] pVec = p.GetVector();
int[][] matrix = ArrayUtils.CreateJagged<int[][]>(N, length);
for (int i = 0; i < N; i++)
Array.Copy(rm._matrix[pVec[i]], 0, matrix[i], 0, length);
result[0] = new GF2Matrix(N, matrix);
// Second part: create inverse matrix
// inverse to lm
GF2Matrix invLm = new GF2Matrix(N, Matrix.MATRIX_TYPE_UNIT);
for (int i = 0; i < N; i++)
{
int rest = i & 0x1f;
int q = IntUtils.URShift(i, 5);
int r = 1 << rest;
for (int j = i + 1; j < N; j++)
{
int b = (lm._matrix[j][q]) & r;
if (b != 0)
{
for (int k = 0; k <= q; k++)
invLm._matrix[j][k] ^= invLm._matrix[i][k];
}
}
}
// inverse to um
GF2Matrix invUm = new GF2Matrix(N, Matrix.MATRIX_TYPE_UNIT);
for (int i = N - 1; i >= 0; i--)
{
int rest = i & 0x1f;
int q = IntUtils.URShift(i, 5);
int r = 1 << rest;
for (int j = i - 1; j >= 0; j--)
{
int b = (um._matrix[j][q]) & r;
if (b != 0)
{
for (int k = q; k < length; k++)
invUm._matrix[j][k] ^= invUm._matrix[i][k];
}
}
}
// inverse matrix
result[1] = (GF2Matrix)invUm.RightMultiply(invLm.RightMultiply(p));
return result;
}
/// <summary>
/// Create an nxn random regular matrix
/// </summary>
///
/// <param name="N">Number of rows (and columns)</param>
/// <param name="SecRnd">Source of randomness</param>
private void AssignRandomRegularMatrix(int N, IRandom SecRnd)
{
RowCount = N;
ColumnCount = N;
_length = IntUtils.URShift((N + 31), 5);
_matrix = ArrayUtils.CreateJagged<int[][]>(RowCount, _length);
GF2Matrix lm = new GF2Matrix(N, Matrix.MATRIX_TYPE_RANDOM_LT, SecRnd);
GF2Matrix um = new GF2Matrix(N, Matrix.MATRIX_TYPE_RANDOM_UT, SecRnd);
GF2Matrix rm = (GF2Matrix)lm.RightMultiply(um);
Permutation perm = new Permutation(N, SecRnd);
int[] p = perm.GetVector();
for (int i = 0; i < N; i++)
Array.Copy(rm._matrix[i], 0, _matrix[p[i]], 0, _length);
}
/// <summary> /// Compute the product of this matrix and a permutation /// </summary> /// /// <param name="P">The permutation</param> /// /// <returns>Returns <c>this * P</c></returns> public abstract Matrix RightMultiply(Permutation P);
/// <summary>
/// Construct a new MaMaPe container with the given parameters
/// </summary>
///
/// <param name="S">The first matrix</param>
/// <param name="H">The second matrix</param>
/// <param name="P">The permutation</param>
public MaMaPe(GF2Matrix S, GF2Matrix H, Permutation P)
{
_s = S;
_h = H;
_p = P;
}
private static MaMaPe GetMMP(GF2Matrix H, IRandom SecRnd)
{
int n = H.ColumnCount;
GF2Matrix s = null;
Permutation p = new Permutation(n, SecRnd);
GF2Matrix hp = (GF2Matrix)H.RightMultiply(p);
GF2Matrix sInv = hp.LeftSubMatrix();
if ((s = InvertMatrix(sInv)) == null)
return null;
GF2Matrix shp = (GF2Matrix)s.RightMultiply(hp);
GF2Matrix m = shp.RightSubMatrix();
return new MaMaPe(sInv, m, p);
}
/// <summary> /// Compute the product of this matrix and a permutation /// </summary> /// /// <param name="P">The permutation</param> /// /// <returns>Returns <c>this * P</c></returns> public abstract Matrix RightMultiply(Permutation P);
/// <summary>
/// Not implemented
/// </summary>
///
/// <param name="P">Permutation P</param>
///
/// <returns>throws NotImplementedException</returns>
public override Matrix RightMultiply(Permutation P)
{
throw new NotImplementedException();
}
private void Dispose(bool Disposing)
{
if (!_isDisposed && Disposing)
{
try
{
if (_gField != null)
{
_gField.Clear();
_gField = null;
}
if (_goppaPoly != null)
{
_goppaPoly.Clear();
_goppaPoly = null;
}
if (_H != null)
{
_H.Clear();
_H = null;
}
if (_P1 != null)
{
_P1.Clear();
_P1 = null;
}
if (_qInv != null)
{
for (int i = 0; i < _qInv.Length; i++)
{
_qInv[i].Clear();
_qInv[i] = null;
}
_qInv = null;
}
_K = 0;
_N = 0;
}
catch { }
_isDisposed = true;
}
}
/// <summary>
/// Multiply this vector with a permutation
/// </summary>
///
/// <param name="P">The permutation</param>
///
/// <returns>Returns <c>this*p = p*this</c></returns>
public override Vector Multiply(Permutation P)
{
int[] pVec = P.GetVector();
if (Length != pVec.Length)
throw new ArithmeticException("GF2Vector: Length mismatch!");
GF2Vector result = new GF2Vector(Length);
for (int i = 0; i < pVec.Length; i++)
{
int e = _elements[pVec[i] >> 5] & (1 << (pVec[i] & 0x1f));
if (e != 0)
result._elements[i >> 5] |= 1 << (i & 0x1f);
}
return result;
}
