/// <summary>
/// Generate an encryption Key pair
/// </summary>
///
/// <returns>A McElieceKeyPair containing public and private keys</returns>
public IAsymmetricKeyPair GenerateKeyPair()
{
// finite field GF(2^m)
GF2mField field = new GF2mField(_M, _fieldPoly);
// irreducible Goppa polynomial
PolynomialGF2mSmallM gp = new PolynomialGF2mSmallM(field, _T, PolynomialGF2mSmallM.RANDOM_IRREDUCIBLE_POLYNOMIAL, _rndEngine);
PolynomialRingGF2m ring = new PolynomialRingGF2m(field, gp);
// matrix for computing square roots in (GF(2^m))^t
PolynomialGF2mSmallM[] qInv = ring.SquareRootMatrix;
// generate canonical check matrix
GF2Matrix h = GoppaCode.CreateCanonicalCheckMatrix(field, gp);
// compute short systematic form of check matrix
GoppaCode.MaMaPe mmp = GoppaCode.ComputeSystematicForm(h, _rndEngine);
GF2Matrix shortH = mmp.SecondMatrix;
Permutation p = mmp.Permutation;
// compute short systematic form of generator matrix
GF2Matrix shortG = (GF2Matrix)shortH.ComputeTranspose();
// obtain number of rows of G (= dimension of the code)
int k = shortG.RowCount;
// generate keys
IAsymmetricKey pubKey = new MPKCPublicKey(_N, _T, shortG);
IAsymmetricKey privKey = new MPKCPrivateKey(_N, k, field, gp, p, h, qInv);
// return key pair
return(new MPKCKeyPair(pubKey, privKey));
}
/// <summary>
/// Decides whether the given object <c>other</c> is the same as this field
/// </summary>
///
/// <param name="Obj">The object for comparison</param>
///
/// <returns>Returns <c>(this == other)</c></returns>
public override bool Equals(Object Obj)
{
if (Obj == null || !(Obj is MPKCPrivateKey))
{
return(false);
}
MPKCPrivateKey key = (MPKCPrivateKey)Obj;
if (!N.Equals(key.N))
{
return(false);
}
if (!K.Equals(key.K))
{
return(false);
}
if (!GF.Equals(key.GF))
{
return(false);
}
if (!GP.Equals(key.GP))
{
return(false);
}
if (!P1.Equals(key.P1))
{
return(false);
}
if (!H.Equals(key.H))
{
return(false);
}
if (QInv.Length != key.QInv.Length)
{
return(false);
}
for (int i = 0; i < QInv.Length; i++)
{
if (!QInv[i].Equals(key.QInv[i]))
{
return(false);
}
}
return(true);
}
/// <summary>
/// Generate an encryption Key pair
/// </summary>
///
/// <returns>A McElieceKeyPair containing public and private keys</returns>
public IAsymmetricKeyPair GenerateKeyPair()
{
// finite field GF(2^m)
GF2mField field = new GF2mField(_M, _fieldPoly);
// irreducible Goppa polynomial
PolynomialGF2mSmallM gp = new PolynomialGF2mSmallM(field, _T, PolynomialGF2mSmallM.RANDOM_IRREDUCIBLE_POLYNOMIAL, _rndEngine);
PolynomialRingGF2m ring = new PolynomialRingGF2m(field, gp);
// matrix for computing square roots in (GF(2^m))^t
PolynomialGF2mSmallM[] qInv = ring.SquareRootMatrix;
// generate canonical check matrix
GF2Matrix h = GoppaCode.CreateCanonicalCheckMatrix(field, gp);
// compute short systematic form of check matrix
GoppaCode.MaMaPe mmp = GoppaCode.ComputeSystematicForm(h, _rndEngine);
GF2Matrix shortH = mmp.SecondMatrix;
Permutation p = mmp.Permutation;
// compute short systematic form of generator matrix
GF2Matrix shortG = (GF2Matrix)shortH.ComputeTranspose();
// obtain number of rows of G (= dimension of the code)
int k = shortG.RowCount;
// generate keys
IAsymmetricKey pubKey = new MPKCPublicKey(_N, _T, shortG);
IAsymmetricKey privKey = new MPKCPrivateKey(_N, k, field, gp, p, h, qInv);
// return key pair
return new MPKCKeyPair(pubKey, privKey);
}
private void TestEncode()
{
MPKCParameters mpar = (MPKCParameters)MPKCParamSets.MPKCFM11T40S256.DeepCopy();
MPKCKeyGenerator mkgen = new MPKCKeyGenerator(mpar);
IAsymmetricKeyPair akp = mkgen.GenerateKeyPair();
MPKCPublicKey pub = (MPKCPublicKey)akp.PublicKey;
byte[] enc = pub.ToBytes();
using (MPKCPublicKey pub2 = MPKCPublicKey.From(enc))
{
if (!pub.Equals(pub2))
throw new Exception("EncryptionKey: public key comparison test failed!");
}
OnProgress(new TestEventArgs("Passed public key serialization"));
MemoryStream pubstr = pub.ToStream();
using (MPKCPublicKey pub2 = MPKCPublicKey.From(pubstr))
{
if (!pub.Equals(pub2))
throw new Exception("EncryptionKey: public key comparison test failed!");
}
pubstr.Dispose();
OnProgress(new TestEventArgs("Passed public key stream test"));
MPKCPrivateKey pri = (MPKCPrivateKey)akp.PrivateKey;
enc = pri.ToBytes();
using (MPKCPrivateKey pri2 = new MPKCPrivateKey(enc))
{
if (!pri.Equals(pri2))
throw new Exception("EncryptionKey: private key comparison test failed!");
}
OnProgress(new TestEventArgs("Passed private key serialization"));
MemoryStream pristr = pri.ToStream();
using (MPKCPrivateKey pri2 = MPKCPrivateKey.From(pristr))
{
if (!pri.Equals(pri2))
throw new Exception("EncryptionKey: private key comparison test failed!");
}
pristr.Dispose();
OnProgress(new TestEventArgs("Passed private key stream test"));
using (MPKCEncrypt mpe = new MPKCEncrypt(mpar))
{
mpe.Initialize(akp.PublicKey);
int sz = mpe.MaxPlainText - 1;
byte[] data = new byte[sz];
new VTDev.Libraries.CEXEngine.Crypto.Prng.CSPRng().GetBytes(data);
enc = mpe.Encrypt(data);
mpe.Initialize(akp.PrivateKey);
byte[] dec = mpe.Decrypt(enc);
if (!Compare.AreEqual(dec, data))
throw new Exception("EncryptionKey: decryption failure!");
OnProgress(new TestEventArgs("Passed encryption test"));
}
pri.Dispose();
pub.Dispose();
}
