Examples with GF2Matrix com.github.zhenwei.core.pqc.math.linearalgebra.GF2Matrix used on opensource projects

Example 6 with GF2Matrix

use of com.github.zhenwei.core.pqc.math.linearalgebra.GF2Matrix in project LinLong-Java by zhenwei1108.

the class McElieceCCA2Primitives method decryptionPrimitive.

/**
 * The McEliece decryption primitive.
 *
 * @param privKey the private key
 * @param c       the ciphertext vector <tt>c = m*G + z</tt>
 * @return the message vector <tt>m</tt> and the error vector <tt>z</tt>
 */
public static GF2Vector[] decryptionPrimitive(BCMcElieceCCA2PrivateKey privKey, GF2Vector c) {
    // obtain values from private key
    int k = privKey.getK();
    Permutation p = privKey.getP();
    GF2mField field = privKey.getField();
    PolynomialGF2mSmallM gp = privKey.getGoppaPoly();
    GF2Matrix h = privKey.getH();
    PolynomialGF2mSmallM[] q = privKey.getQInv();
    // compute inverse permutation P^-1
    Permutation pInv = p.computeInverse();
    // multiply c with permutation P^-1
    GF2Vector cPInv = (GF2Vector) c.multiply(pInv);
    // compute syndrome of cP^-1
    GF2Vector syndVec = (GF2Vector) h.rightMultiply(cPInv);
    // decode syndrome
    GF2Vector errors = GoppaCode.syndromeDecode(syndVec, field, gp, q);
    GF2Vector mG = (GF2Vector) cPInv.add(errors);
    // multiply codeword and error vector with P
    mG = (GF2Vector) mG.multiply(p);
    errors = (GF2Vector) errors.multiply(p);
    // extract plaintext vector (last k columns of mG)
    GF2Vector m = mG.extractRightVector(k);
    // return vectors
    return new GF2Vector[] { m, errors };
}

Example 7 with GF2Matrix

use of com.github.zhenwei.core.pqc.math.linearalgebra.GF2Matrix in project LinLong-Java by zhenwei1108.

the class McElieceCCA2KeyPairGenerator method generateKeyPair.

public AsymmetricCipherKeyPair generateKeyPair() {
    if (!initialized) {
        initializeDefault();
    }
    // finite field GF(2^m)
    GF2mField field = new GF2mField(m, fieldPoly);
    // irreducible Goppa polynomial
    PolynomialGF2mSmallM gp = new PolynomialGF2mSmallM(field, t, PolynomialGF2mSmallM.RANDOM_IRREDUCIBLE_POLYNOMIAL, random);
    // generate canonical check matrix
    GF2Matrix h = GoppaCode.createCanonicalCheckMatrix(field, gp);
    // compute short systematic form of check matrix
    MaMaPe mmp = GoppaCode.computeSystematicForm(h, random);
    GF2Matrix shortH = mmp.getSecondMatrix();
    Permutation p = mmp.getPermutation();
    // 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.getNumRows();
    // generate keys
    McElieceCCA2PublicKeyParameters pubKey = new McElieceCCA2PublicKeyParameters(n, t, shortG, mcElieceCCA2Params.getParameters().getDigest());
    McElieceCCA2PrivateKeyParameters privKey = new McElieceCCA2PrivateKeyParameters(n, k, field, gp, p, mcElieceCCA2Params.getParameters().getDigest());
    // return key pair
    return new AsymmetricCipherKeyPair(pubKey, privKey);
}

Example 8 with GF2Matrix

use of com.github.zhenwei.core.pqc.math.linearalgebra.GF2Matrix in project LinLong-Java by zhenwei1108.

the class McElieceCCA2Primitives method encryptionPrimitive.

/**
 * The McEliece encryption primitive.
 *
 * @param pubKey the public key
 * @param m      the message vector
 * @param z      the error vector
 * @return <tt>m*G + z</tt>
 */
public static GF2Vector encryptionPrimitive(McElieceCCA2PublicKeyParameters pubKey, GF2Vector m, GF2Vector z) {
    GF2Matrix matrixG = pubKey.getG();
    Vector mG = matrixG.leftMultiplyLeftCompactForm(m);
    return (GF2Vector) mG.add(z);
}

Example 9 with GF2Matrix

use of com.github.zhenwei.core.pqc.math.linearalgebra.GF2Matrix in project LinLong-Java by zhenwei1108.

the class McElieceCipher method messageEncrypt.

/**
 * Encrypt a plain text.
 *
 * @param input the plain text
 * @return the cipher text
 */
public byte[] messageEncrypt(byte[] input) {
    if (!forEncryption) {
        throw new IllegalStateException("cipher initialised for decryption");
    }
    GF2Vector m = computeMessageRepresentative(input);
    GF2Vector z = new GF2Vector(n, t, sr);
    GF2Matrix g = ((McEliecePublicKeyParameters) key).getG();
    Vector mG = g.leftMultiply(m);
    GF2Vector mGZ = (GF2Vector) mG.add(z);
    return mGZ.getEncoded();
}

Example 10 with GF2Matrix

use of com.github.zhenwei.core.pqc.math.linearalgebra.GF2Matrix in project LinLong-Java by zhenwei1108.

the class McElieceCCA2Primitives method decryptionPrimitive.

public static GF2Vector[] decryptionPrimitive(McElieceCCA2PrivateKeyParameters privKey, GF2Vector c) {
    // obtain values from private key
    int k = privKey.getK();
    Permutation p = privKey.getP();
    GF2mField field = privKey.getField();
    PolynomialGF2mSmallM gp = privKey.getGoppaPoly();
    GF2Matrix h = privKey.getH();
    PolynomialGF2mSmallM[] q = privKey.getQInv();
    // compute inverse permutation P^-1
    Permutation pInv = p.computeInverse();
    // multiply c with permutation P^-1
    GF2Vector cPInv = (GF2Vector) c.multiply(pInv);
    // compute syndrome of cP^-1
    GF2Vector syndVec = (GF2Vector) h.rightMultiply(cPInv);
    // decode syndrome
    GF2Vector errors = GoppaCode.syndromeDecode(syndVec, field, gp, q);
    GF2Vector mG = (GF2Vector) cPInv.add(errors);
    // multiply codeword and error vector with P
    mG = (GF2Vector) mG.multiply(p);
    errors = (GF2Vector) errors.multiply(p);
    // extract plaintext vector (last k columns of mG)
    GF2Vector m = mG.extractRightVector(k);
    // return vectors
    return new GF2Vector[] { m, errors };
}