/// <summary>
/// Given a check matrix <c>H</c>, compute matrices <c>S</c>, <c>M</c>, and a random permutation <c>P</c> such that
/// <c>S*H*P = (Id|M)</c>. Return <c>S^-1</c>, <c>M</c>, and the systematic form of H
/// </summary>
///
/// <param name="H">The check matrix</param>
/// <param name="SecRnd">The source of randomness</param>
///
/// <returns>Returns the tuple <c>(S^-1, M, P)</c></returns>
public static MaMaPe ComputeSystematicForm(GF2Matrix H, IRandom SecRnd)
{
MaMaPe mmp = null;
object lockobj = new object();
if (ParallelUtils.IsParallel)
{
Func <bool> condFn = () => mmp == null;
ParallelUtils.Loop(new ParallelOptions(), condFn, loopState =>
{
MaMaPe mmp2 = GetMMP(H, SecRnd);
if (mmp2 != null)
{
lock (mmp2)
{
mmp = mmp2;
}
}
});
}
else
{
do
{
mmp = GetMMP(H, SecRnd);
}while (mmp == null);
}
return(mmp);
}
/// <summary>
/// Given a check matrix <c>H</c>, compute matrices <c>S</c>, <c>M</c>, and a random permutation <c>P</c> such that
/// <c>S*H*P = (Id|M)</c>. Return <c>S^-1</c>, <c>M</c>, and the systematic form of H
/// </summary>
///
/// <param name="H">The check matrix</param>
/// <param name="SecRnd">The source of randomness</param>
///
/// <returns>Returns the tuple <c>(S^-1, M, P)</c></returns>
public static MaMaPe ComputeSystematicForm(GF2Matrix H, IRandom SecRnd)
{
MaMaPe mmp = null;
object lockobj = new object();
if (ParallelUtils.IsParallel)
{
Func<bool> condFn = () => mmp == null;
ParallelUtils.Loop(new ParallelOptions(), condFn, loopState =>
{
MaMaPe mmp2 = GetMMP(H, SecRnd);
if (mmp2 != null)
{
lock (mmp2)
{
mmp = mmp2;
}
}
});
}
else
{
do
{
mmp = GetMMP(H, SecRnd);
}
while (mmp == null);
}
return mmp;
}
/// <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)//3
{
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>
/// 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;
}
private static GF2Matrix InvertMatrix(GF2Matrix Matrix)
{
try
{
return((GF2Matrix)Matrix.ComputeInverse());
}
catch
{
return(null);
}
}
/// <summary>
/// Copy constructor
/// </summary>
///
/// <param name="A">A GF2Matrix to copy</param>
public GF2Matrix(GF2Matrix A)
{
ColumnCount = A.ColumnCount;
RowCount = A.RowCount;
_length = A._length;
_matrix = new int[A._matrix.Length][];
for (int i = 0; i < _matrix.Length; i++)
{
_matrix[i] = IntUtils.DeepCopy(A._matrix[i]);
}
}
/// <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>
/// Reconstructs a public key from its <c>byte</c> array representation.
/// </summary>
///
/// <param name="KeyStream">An input stream containing an encoded key</param>
///
/// <exception cref="MPKCException">Thrown if the key could not be loaded</exception>
public MPKCPublicKey(Stream KeyStream)
{
try
{
BinaryReader reader = new BinaryReader(KeyStream);
_N = reader.ReadInt32();
_T = reader.ReadInt32();
_G = new GF2Matrix(reader.ReadBytes((int)(reader.BaseStream.Length - reader.BaseStream.Position)));
}
catch (IOException ex)
{
throw new MPKCException("MPKCPublicKey:CTor", "The Public key could not be loaded!", ex);
}
}
/// <summary>
/// Compute the full form matrix <c>(this | Id)</c> from this matrix in left compact form.
/// <para>Where <c>Id</c> is the <c>k x k</c> identity matrix and <c>k</c> is the number of rows of this matrix.</para>
/// </summary>
///
/// <returns>Returns <c>(this | Id)</c></returns>
public GF2Matrix ExtendLeftCompactForm()
{
int newNumColumns = ColumnCount + RowCount;
GF2Matrix result = new GF2Matrix(RowCount, newNumColumns);
int ind = RowCount - 1 + ColumnCount;
for (int i = RowCount - 1; i >= 0; i--, ind--)
{
// copy this matrix to first columns
Array.Copy(_matrix[i], 0, result._matrix[i], 0, _length);
// store the identity in last columns
result._matrix[i][ind >> 5] |= 1 << (ind & 0x1f);
}
return(result);
}
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>
/// 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 full form matrix <c>(Id | this)</c> from this matrix in right compact form.
/// <para>Where <c>Id</c> is the <c>k x k</c> identity matrix and <c>k</c> is the number of rows of this matrix.</para>
/// </summary>
///
/// <returns>Returns <c>(Id | this)</c></returns>
public GF2Matrix ExtendRightCompactForm()
{
GF2Matrix result = new GF2Matrix(RowCount, RowCount + ColumnCount);
int q = RowCount >> 5;
int r = RowCount & 0x1f;
for (int i = RowCount - 1; i >= 0; i--)
{
// store the identity in first columns
result._matrix[i][i >> 5] |= 1 << (i & 0x1f);
// copy this matrix to last columns if words have to be shifted
if (r != 0)
{
int ind = q;
// process all but last word
for (int j = 0; j < _length - 1; j++)
{
// obtain matrix word
int mw = _matrix[i][j];
// shift to correct position
result._matrix[i][ind++] |= mw << r;
result._matrix[i][ind] |= IntUtils.URShift(mw, (32 - r));
}
// process last word
int mwv = _matrix[i][_length - 1];
result._matrix[i][ind++] |= mwv << r;
if (ind < result._length)
{
result._matrix[i][ind] |= IntUtils.URShift(mwv, (32 - r));
}
}
else
{
// no shifting necessary
Array.Copy(_matrix[i], 0, result._matrix[i], q, _length);
}
}
return(result);
}
/// <summary>
/// Get the submatrix of this matrix consisting of the rightmost <c>numColumns-numRows</c> columns
/// </summary>
///
/// <returns>Returns the <c>(numRows x (numColumns-numRows))</c> submatrix</returns>
public GF2Matrix RightSubMatrix()
{
if (ColumnCount <= RowCount)
{
throw new ArithmeticException("GF2Matrix: empty submatrix!");
}
int q = RowCount >> 5;
int r = RowCount & 0x1f;
GF2Matrix result = new GF2Matrix(RowCount, ColumnCount - RowCount);
for (int i = RowCount - 1; i >= 0; i--)
{
// if words have to be shifted
if (r != 0)
{
int ind = q;
// process all but last word and shift to correct position
for (int j = 0; j < result._length - 1; j++)
{
result._matrix[i][j] = (IntUtils.URShift(_matrix[i][ind++], r)) | (_matrix[i][ind] << (32 - r));
}
// process last word
result._matrix[i][result._length - 1] = IntUtils.URShift(_matrix[i][ind++], r);
if (ind < _length)
{
result._matrix[i][result._length - 1] |= _matrix[i][ind] << (32 - r);
}
}
else
{
// no shifting necessary
Array.Copy(_matrix[i], q, result._matrix[i], 0, result._length);
}
}
return(result);
}
/// <summary>
/// Compare this matrix with another object.
/// </summary>
///
/// <param name="Obj">The object to compare this to</param>
/// <returns>Returns <c>true</c> if object is equal and has the same values</returns>
public override bool Equals(Object Obj)
{
if (!(Obj is GF2Matrix))
{
return(false);
}
GF2Matrix otherMatrix = (GF2Matrix)Obj;
if ((RowCount != otherMatrix.RowCount) || (ColumnCount != otherMatrix.ColumnCount) || (_length != otherMatrix._length))
{
return(false);
}
for (int i = 0; i < RowCount; i++)
{
if (!Compare.AreEqual(_matrix[i], otherMatrix._matrix[i]))
{
return(false);
}
}
return(true);
}
/// <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;
}
/// <summary>
/// Compute the product of this matrix and a matrix A over GF(2)
/// </summary>
///
/// <param name="M">A matrix A over GF(2)</param>
///
/// <returns>Returns matrix product <c>this*M</c></returns>
public override Matrix RightMultiply(Matrix M)
{
if (!(M is GF2Matrix))
{
throw new ArithmeticException("GF2Matrix: Matrix is not defined over GF(2)!");
}
if (M.RowCount != ColumnCount)
{
throw new ArithmeticException("GF2Matrix: Length mismatch!");
}
GF2Matrix a = (GF2Matrix)M;
GF2Matrix result = new GF2Matrix(RowCount, M.ColumnCount);
int d;
int rest = ColumnCount & 0x1f;
if (rest == 0)
{
d = _length;
}
else
{
d = _length - 1;
}
for (int i = 0; i < RowCount; i++)
{
int count = 0;
for (int j = 0; j < d; j++)
{
int e = _matrix[i][j];
for (int h = 0; h < 32; h++)
{
int b = e & (1 << h);
if (b != 0)
{
for (int g = 0; g < a._length; g++)
{
result._matrix[i][g] ^= a._matrix[count][g];
}
}
count++;
}
}
int e1 = _matrix[i][_length - 1];
for (int h = 0; h < rest; h++)
{
int b = e1 & (1 << h);
if (b != 0)
{
for (int g = 0; g < a._length; g++)
{
result._matrix[i][g] ^= a._matrix[count][g];
}
}
count++;
}
}
return(result);
}
/// <summary>
/// Get the submatrix of this matrix consisting of the rightmost <c>numColumns-numRows</c> columns
/// </summary>
///
/// <returns>Returns the <c>(numRows x (numColumns-numRows))</c> submatrix</returns>
public GF2Matrix RightSubMatrix()
{
if (ColumnCount <= RowCount)
throw new ArithmeticException("GF2Matrix: empty submatrix!");
int q = RowCount >> 5;
int r = RowCount & 0x1f;
GF2Matrix result = new GF2Matrix(RowCount, ColumnCount - RowCount);
for (int i = RowCount - 1; i >= 0; i--)
{
// if words have to be shifted
if (r != 0)
{
int ind = q;
// process all but last word and shift to correct position
for (int j = 0; j < result._length - 1; j++)
result._matrix[i][j] = (IntUtils.URShift(_matrix[i][ind++], r)) | (_matrix[i][ind] << (32 - r));
// process last word
result._matrix[i][result._length - 1] = IntUtils.URShift(_matrix[i][ind++], r);
if (ind < _length)
result._matrix[i][result._length - 1] |= _matrix[i][ind] << (32 - r);
}
else
{
// no shifting necessary
Array.Copy(_matrix[i], q, result._matrix[i], 0, result._length);
}
}
return result;
}
/// <summary>
/// Constructor used by McElieceKeyFactory
/// </summary>
///
/// <param name="T">The error correction capability of the code</param>
/// <param name="N">The length of the code</param>
/// <param name="G">The encoded generator matrix</param>
public MPKCPublicKey(int T, int N, byte[] G)
{
_N = N;
_T = T;
_G = new GF2Matrix(G);
}
//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 full form matrix <c>(this | Id)</c> from this matrix in left compact form.
/// <para>Where <c>Id</c> is the <c>k x k</c> identity matrix and <c>k</c> is the number of rows of this matrix.</para>
/// </summary>
///
/// <returns>Returns <c>(this | Id)</c></returns>
public GF2Matrix ExtendLeftCompactForm()
{
int newNumColumns = ColumnCount + RowCount;
GF2Matrix result = new GF2Matrix(RowCount, newNumColumns);
int ind = RowCount - 1 + ColumnCount;
for (int i = RowCount - 1; i >= 0; i--, ind--)
{
// copy this matrix to first columns
Array.Copy(_matrix[i], 0, result._matrix[i], 0, _length);
// store the identity in last columns
result._matrix[i][ind >> 5] |= 1 << (ind & 0x1f);
}
return 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>
/// Copy constructor
/// </summary>
///
/// <param name="A">A GF2Matrix to copy</param>
public GF2Matrix(GF2Matrix A)
{
ColumnCount = A.ColumnCount;
RowCount = A.RowCount;
_length = A._length;
_matrix = new int[A._matrix.Length][];
for (int i = 0; i < _matrix.Length; i++)
_matrix[i] = IntUtils.DeepCopy(A._matrix[i]);
}
/// <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>
/// onstruct a new MatrixSet container with the given parameters
/// </summary>
///
/// <param name="G">The generator matrix</param>
/// <param name="SetJ">The set of indices such that the submatrix of the generator matrix
/// consisting of the specified columns is the identity</param>
public MatrixSet(GF2Matrix G, int[] SetJ)
{
_g = G;
_setJ = SetJ;
}
/// <summary>
/// onstruct a new MatrixSet container with the given parameters
/// </summary>
///
/// <param name="G">The generator matrix</param>
/// <param name="SetJ">The set of indices such that the submatrix of the generator matrix
/// consisting of the specified columns is the identity</param>
public MatrixSet(GF2Matrix G, int[] SetJ)
{
_g = G;
_setJ = SetJ;
}
/// <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 GF2Matrix InvertMatrix(GF2Matrix Matrix)
{
try
{
return (GF2Matrix)Matrix.ComputeInverse();
}
catch
{
return null;
}
}
/// <summary>
/// Compute the full form matrix <c>(Id | this)</c> from this matrix in right compact form.
/// <para>Where <c>Id</c> is the <c>k x k</c> identity matrix and <c>k</c> is the number of rows of this matrix.</para>
/// </summary>
///
/// <returns>Returns <c>(Id | this)</c></returns>
public GF2Matrix ExtendRightCompactForm()
{
GF2Matrix result = new GF2Matrix(RowCount, RowCount + ColumnCount);
int q = RowCount >> 5;
int r = RowCount & 0x1f;
for (int i = RowCount - 1; i >= 0; i--)
{
// store the identity in first columns
result._matrix[i][i >> 5] |= 1 << (i & 0x1f);
// copy this matrix to last columns if words have to be shifted
if (r != 0)
{
int ind = q;
// process all but last word
for (int j = 0; j < _length - 1; j++)
{
// obtain matrix word
int mw = _matrix[i][j];
// shift to correct position
result._matrix[i][ind++] |= mw << r;
result._matrix[i][ind] |= IntUtils.URShift(mw, (32 - r));
}
// process last word
int mwv = _matrix[i][_length - 1];
result._matrix[i][ind++] |= mwv << r;
if (ind < result._length)
result._matrix[i][ind] |= IntUtils.URShift(mwv, (32 - r));
}
else
{
// no shifting necessary
Array.Copy(_matrix[i], 0, result._matrix[i], q, _length);
}
}
return result;
}
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 matrix A over GF(2)
/// </summary>
///
/// <param name="M">A matrix A over GF(2)</param>
///
/// <returns>Returns matrix product <c>this*M</c></returns>
public override Matrix RightMultiply(Matrix M)
{
if (!(M is GF2Matrix))
throw new ArithmeticException("GF2Matrix: Matrix is not defined over GF(2)!");
if (M.RowCount != ColumnCount)
throw new ArithmeticException("GF2Matrix: Length mismatch!");
GF2Matrix a = (GF2Matrix)M;
GF2Matrix result = new GF2Matrix(RowCount, M.ColumnCount);
int d;
int rest = ColumnCount & 0x1f;
if (rest == 0)
d = _length;
else
d = _length - 1;
for (int i = 0; i < RowCount; i++)
{
int count = 0;
for (int j = 0; j < d; j++)
{
int e = _matrix[i][j];
for (int h = 0; h < 32; h++)
{
int b = e & (1 << h);
if (b != 0)
{
for (int g = 0; g < a._length; g++)
result._matrix[i][g] ^= a._matrix[count][g];
}
count++;
}
}
int e1 = _matrix[i][_length - 1];
for (int h = 0; h < rest; h++)
{
int b = e1 & (1 << h);
if (b != 0)
{
for (int g = 0; g < a._length; g++)
result._matrix[i][g] ^= a._matrix[count][g];
}
count++;
}
}
return result;
}
/// <summary>
/// Initialize this class
/// </summary>
///
/// <param name="N">The length of the code</param>
/// <param name="T">The error correction capability of the code</param>
/// <param name="G">The generator matrix</param>
internal MPKCPublicKey(int N, int T, GF2Matrix G)
{
_N = N;
_T = T;
_G = new GF2Matrix(G);
}
private void Dispose(bool Disposing)
{
if (!_isDisposed && Disposing)
{
try
{
if (_G != null)
{
_G.Clear();
_G = null;
}
_N = 0;
_T = 0;
}
catch { }
_isDisposed = true;
}
}
/// <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);
}
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;
}
}