Examples with ECPoint java.security.spec.ECPoint used on opensource projects

Example 91 with ECPoint

use of java.security.spec.ECPoint in project wycheproof by google.

the class EcUtil method getBrainpoolP224r1Params.

public static ECParameterSpec getBrainpoolP224r1Params() {
    // name = "brainpoolP224r1",
    // oid = '2b2403030208010105',
    // ref = "RFC 5639",
    BigInteger p = new BigInteger("D7C134AA264366862A18302575D1D787B09F075797DA89F57EC8C0FF", 16);
    BigInteger a = new BigInteger("68A5E62CA9CE6C1C299803A6C1530B514E182AD8B0042A59CAD29F43", 16);
    BigInteger b = new BigInteger("2580F63CCFE44138870713B1A92369E33E2135D266DBB372386C400B", 16);
    BigInteger x = new BigInteger("0D9029AD2C7E5CF4340823B2A87DC68C9E4CE3174C1E6EFDEE12C07D", 16);
    BigInteger y = new BigInteger("58AA56F772C0726F24C6B89E4ECDAC24354B9E99CAA3F6D3761402CD", 16);
    BigInteger n = new BigInteger("D7C134AA264366862A18302575D0FB98D116BC4B6DDEBCA3A5A7939F", 16);
    final int h = 1;
    ECFieldFp fp = new ECFieldFp(p);
    EllipticCurve curve = new EllipticCurve(fp, a, b);
    ECPoint g = new ECPoint(x, y);
    return new ECParameterSpec(curve, g, n, h);
}

Example 92 with ECPoint

use of java.security.spec.ECPoint in project wycheproof by google.

the class EcUtil method decompressPoint.

/**
 * Decompress a point on an elliptic curve.
 *
 * @param bytes The compressed point. Its representation is z || x where z is 2+lsb(y) and x is
 *     using a unsigned fixed length big-endian representation.
 * @param ecParams the specification of the curve. Only Weierstrass curves over prime order fields
 *     are implemented.
 */
public static ECPoint decompressPoint(byte[] bytes, ECParameterSpec ecParams) throws GeneralSecurityException {
    EllipticCurve ec = ecParams.getCurve();
    ECField field = ec.getField();
    if (!(field instanceof ECFieldFp)) {
        throw new GeneralSecurityException("Only curves over prime order fields are supported");
    }
    BigInteger p = ((java.security.spec.ECFieldFp) field).getP();
    int expectedLength = 1 + (p.bitLength() + 7) / 8;
    if (bytes.length != expectedLength) {
        throw new GeneralSecurityException("compressed point has wrong length");
    }
    boolean lsb;
    switch(bytes[0]) {
        case 2:
            lsb = false;
            break;
        case 3:
            lsb = true;
            break;
        default:
            throw new GeneralSecurityException("Invalid format");
    }
    BigInteger x = new BigInteger(1, Arrays.copyOfRange(bytes, 1, bytes.length));
    if (x.compareTo(BigInteger.ZERO) == -1 || x.compareTo(p) != -1) {
        throw new GeneralSecurityException("x is out of range");
    }
    // Compute rhs == x^3 + a x + b (mod p)
    BigInteger rhs = x.multiply(x).add(ec.getA()).multiply(x).add(ec.getB()).mod(p);
    BigInteger y = modSqrt(rhs, p);
    if (lsb != y.testBit(0)) {
        y = p.subtract(y).mod(p);
    }
    return new ECPoint(x, y);
}

Example 93 with ECPoint

use of java.security.spec.ECPoint in project wycheproof by google.

the class EcUtil method getNistCurveSpec.

public static ECParameterSpec getNistCurveSpec(String decimalP, String decimalN, String hexB, String hexGX, String hexGY) {
    final BigInteger p = new BigInteger(decimalP);
    final BigInteger n = new BigInteger(decimalN);
    final BigInteger three = new BigInteger("3");
    final BigInteger a = p.subtract(three);
    final BigInteger b = new BigInteger(hexB, 16);
    final BigInteger gx = new BigInteger(hexGX, 16);
    final BigInteger gy = new BigInteger(hexGY, 16);
    final int h = 1;
    ECFieldFp fp = new ECFieldFp(p);
    java.security.spec.EllipticCurve curveSpec = new java.security.spec.EllipticCurve(fp, a, b);
    ECPoint g = new ECPoint(gx, gy);
    ECParameterSpec ecSpec = new ECParameterSpec(curveSpec, g, n, h);
    return ecSpec;
}

Example 94 with ECPoint

use of java.security.spec.ECPoint in project wycheproof by google.

the class EcUtil method getBrainpoolP256r1Params.

public static ECParameterSpec getBrainpoolP256r1Params() {
    BigInteger p = new BigInteger("A9FB57DBA1EEA9BC3E660A909D838D726E3BF623D52620282013481D1F6E5377", 16);
    BigInteger a = new BigInteger("7D5A0975FC2C3057EEF67530417AFFE7FB8055C126DC5C6CE94A4B44F330B5D9", 16);
    BigInteger b = new BigInteger("26DC5C6CE94A4B44F330B5D9BBD77CBF958416295CF7E1CE6BCCDC18FF8C07B6", 16);
    BigInteger x = new BigInteger("8BD2AEB9CB7E57CB2C4B482FFC81B7AFB9DE27E1E3BD23C23A4453BD9ACE3262", 16);
    BigInteger y = new BigInteger("547EF835C3DAC4FD97F8461A14611DC9C27745132DED8E545C1D54C72F046997", 16);
    BigInteger n = new BigInteger("A9FB57DBA1EEA9BC3E660A909D838D718C397AA3B561A6F7901E0E82974856A7", 16);
    final int h = 1;
    ECFieldFp fp = new ECFieldFp(p);
    EllipticCurve curve = new EllipticCurve(fp, a, b);
    ECPoint g = new ECPoint(x, y);
    return new ECParameterSpec(curve, g, n, h);
}

Example 95 with ECPoint

use of java.security.spec.ECPoint in project dhis2-core by dhis2.

the class TestKeys method generateEcKeyPair.

static KeyPair generateEcKeyPair() {
    EllipticCurve ellipticCurve = new EllipticCurve(new ECFieldFp(new BigInteger("115792089210356248762697446949407573530086143415290314195533631308867097853951")), new BigInteger("115792089210356248762697446949407573530086143415290314195533631308867097853948"), new BigInteger("41058363725152142129326129780047268409114441015993725554835256314039467401291"));
    ECPoint ecPoint = new ECPoint(new BigInteger("48439561293906451759052585252797914202762949526041747995844080717082404635286"), new BigInteger("36134250956749795798585127919587881956611106672985015071877198253568414405109"));
    ECParameterSpec ecParameterSpec = new ECParameterSpec(ellipticCurve, ecPoint, new BigInteger("115792089210356248762697446949407573529996955224135760342422259061068512044369"), 1);
    KeyPair keyPair;
    try {
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("EC");
        keyPairGenerator.initialize(ecParameterSpec);
        keyPair = keyPairGenerator.generateKeyPair();
    } catch (Exception ex) {
        throw new IllegalStateException(ex);
    }
    return keyPair;
}