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

Example 26 with ECFieldFp

use of java.security.spec.ECFieldFp in project j2objc by google.

the class EllipticCurveTest method testEllipticCurveECFieldBigIntegerBigIntegerbyteArray01.

/**
     * Test #1 for <code>EllipticCurve(ECField, BigInteger, BigInteger, byte[])</code>
     * constructor<br>
     * Assertion: creates instance of EllipticCurve<br>
     * Test preconditions: valid parameters passed<br>
     * Expected: must pass without any exceptions
     */
public final void testEllipticCurveECFieldBigIntegerBigIntegerbyteArray01() {
    // test case 1 parameters set
    ECFieldFp f = new ECFieldFp(BigInteger.valueOf(23L));
    BigInteger a = BigInteger.ONE;
    BigInteger b = BigInteger.valueOf(19L);
    byte[] seed = new byte[24];
    // perform test case 1
    new EllipticCurve(f, a, b, seed);
    // test case 2 parameters set
    ECFieldF2m f1 = new ECFieldF2m(5);
    a = BigInteger.ZERO;
    b = BigInteger.valueOf(23L);
    // perform test case 2
    new EllipticCurve(f1, a, b, seed);
    // test case 3 parameters set,
    // the seed parameter may be null
    f = new ECFieldFp(BigInteger.valueOf(23L));
    a = BigInteger.ONE;
    b = BigInteger.valueOf(19L);
    seed = null;
    // perform test case 3
    new EllipticCurve(f, a, b, seed);
}

Example 27 with ECFieldFp

use of java.security.spec.ECFieldFp in project j2objc by google.

the class EllipticCurveTest method testEllipticCurveECFieldBigIntegerBigInteger03.

/**
     * Test #3 for <code>EllipticCurve(ECField, BigInteger, BigInteger)</code>
     * constructor<br>
     * Assertion: throws <code>IllegalArgumentException</code> if
     * <code>a</code> or <code>b</code> is not <code>null</code> and not in
     * the <code>field</code><br>
     * Test preconditions: pass <code>a</code>, <code>b</code> which are
     * not in the <code>field</code> of type <code>ECFieldFp</code><br>
     * Expected: must throw <code>IllegalArgumentException</code>
     */
public final void testEllipticCurveECFieldBigIntegerBigInteger03() {
    // test case 1 parameters set,
    // a is not in field
    ECFieldFp f = new ECFieldFp(BigInteger.valueOf(23L));
    BigInteger a = BigInteger.valueOf(24L);
    BigInteger b = BigInteger.valueOf(19L);
    // perform test case 1
    try {
        new EllipticCurve(f, a, b);
        fail("#1: Expected IAE not thrown");
    } catch (IllegalArgumentException ok) {
    }
    // test case 1.1 parameters set,
    // a is not in field
    f = new ECFieldFp(BigInteger.valueOf(23L));
    a = BigInteger.valueOf(23L);
    b = BigInteger.valueOf(19L);
    // perform test case 1.1
    try {
        new EllipticCurve(f, a, b);
        fail("#1.1: Expected IAE not thrown");
    } catch (IllegalArgumentException ok) {
    }
    // test case 2 parameters set,
    // b is not in field
    f = new ECFieldFp(BigInteger.valueOf(23L));
    a = BigInteger.valueOf(19L);
    b = BigInteger.valueOf(24L);
    // perform test case 2
    try {
        new EllipticCurve(f, a, b);
        fail("#2: Expected IAE not thrown");
    } catch (IllegalArgumentException ok) {
    }
    // test case 3 parameters set,
    // both a and b are not in field
    f = new ECFieldFp(BigInteger.valueOf(23L));
    a = BigInteger.valueOf(25L);
    b = BigInteger.valueOf(240L);
    // perform test case 3
    try {
        new EllipticCurve(f, a, b);
        fail("#3: Expected IAE not thrown");
    } catch (IllegalArgumentException ok) {
    }
}

Example 28 with ECFieldFp

use of java.security.spec.ECFieldFp in project j2objc by google.

the class EllipticCurveTest method testGetSeed03.

/**
     * Test #3 for <code>getSeed()</code> method<br>
     * Assertion: returned array is copied to prevent subsequent modification<br>
     * Test preconditions: <code>ECFieldF2m</code> instance
     * created using valid parameters<br>
     * Expected: repeated method calls must return different refs
     */
public final void testGetSeed03() {
    ECFieldFp f = new ECFieldFp(BigInteger.valueOf(23L));
    BigInteger a = BigInteger.ONE;
    BigInteger b = BigInteger.valueOf(19L);
    byte[] seed = new byte[24];
    EllipticCurve c = new EllipticCurve(f, a, b, seed);
    c.getSeed();
    assertNotSame(c.getSeed(), c.getSeed());
}

Example 29 with ECFieldFp

use of java.security.spec.ECFieldFp 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 30 with ECFieldFp

use of java.security.spec.ECFieldFp 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);
}