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

Example 6 with ECField

use of java.security.spec.ECField in project robovm by robovm.

the class OpenSSLECGroupContext method getECParameterSpec.

public ECParameterSpec getECParameterSpec() {
    final String curveName = NativeCrypto.EC_GROUP_get_curve_name(groupCtx);
    final byte[][] curveParams = NativeCrypto.EC_GROUP_get_curve(groupCtx);
    final BigInteger p = new BigInteger(curveParams[0]);
    final BigInteger a = new BigInteger(curveParams[1]);
    final BigInteger b = new BigInteger(curveParams[2]);
    final ECField field;
    final int type = NativeCrypto.get_EC_GROUP_type(groupCtx);
    if (type == NativeCrypto.EC_CURVE_GFP) {
        field = new ECFieldFp(p);
    } else if (type == NativeCrypto.EC_CURVE_GF2M) {
        field = new ECFieldF2m(p.bitLength() - 1, p);
    } else {
        throw new RuntimeException("unknown curve type " + type);
    }
    final EllipticCurve curve = new EllipticCurve(field, a, b);
    final OpenSSLECPointContext generatorCtx = new OpenSSLECPointContext(this, NativeCrypto.EC_GROUP_get_generator(groupCtx));
    final ECPoint generator = generatorCtx.getECPoint();
    final BigInteger order = new BigInteger(NativeCrypto.EC_GROUP_get_order(groupCtx));
    final BigInteger cofactor = new BigInteger(NativeCrypto.EC_GROUP_get_cofactor(groupCtx));
    return new ECParameterSpec(curve, generator, order, cofactor.intValue(), curveName);
}