SecureRandom    k = new SecureRandom() { public void nextBytes(byte[] bytes) { byte[] k = new BigInteger("700000017569056646655505781757157107570501575775705779575555657156756655").toByteArray();
byte[] kData = BigIntegers.asUnsignedByteArray(new BigInteger("700000017569056646655505781757157107570501575775705779575555657156756655"));
    private void testECDSA239bitPrime()        throws Exception    {        BigInteger r = new BigInteger("308636143175167811492622547300668018854959378758531778147462058306432176");        BigInteger s = new BigInteger("323813553209797357708078776831250505931891051755007842781978505179448783");        SecureRandom    k = new SecureRandom()        {            public void nextBytes(byte[] bytes)            {                byte[] k = new BigInteger("700000017569056646655505781757157107570501575775705779575555657156756655").toByteArray();                System.arraycopy(k, k.length-bytes.length, bytes, 0, bytes.length);            }        };        EllipticCurve curve = new EllipticCurve(            new ECFieldFp(new BigInteger("883423532389192164791648750360308885314476597252960362792450860609699839")), // q            new BigInteger("7fffffffffffffffffffffff7fffffffffff8000000000007ffffffffffc", 16), // a            new BigInteger("6b016c3bdcf18941d0d654921475ca71a9db2fb27d1d37796185c2942c0a", 16)); // b        ECParameterSpec spec = new ECParameterSpec(            curve,            ECPointUtil.decodePoint(curve, Hex.decode("020ffa963cdca8816ccc33b8642bedf905c3d358573d3f27fbbd3b3cb9aaaf")), // G            new BigInteger("883423532389192164791648750360308884807550341691627752275345424702807307"), // n            1); // h                ECPrivateKeySpec priKey = new ECPrivateKeySpec(            new BigInteger("876300101507107567501066130761671078357010671067781776716671676178726717"), // d            spec);        ECPublicKeySpec pubKey = new ECPublicKeySpec(            ECPointUtil.decodePoint(curve, Hex.decode("025b6dc53bc61a2548ffb0f671472de6c9521a9d2d2534e65abfcbd5fe0c70")), // Q            spec);        Signature           sgr = Signature.getInstance("ECDSA", "BC");        KeyFactory          f = KeyFactory.getInstance("ECDSA", "BC");        PrivateKey          sKey = f.generatePrivate(priKey);        PublicKey           vKey = f.generatePublic(pubKey);        sgr.initSign(sKey, k);        byte[] message = new byte[] { (byte)'a', (byte)'b', (byte)'c' };        sgr.update(message);        byte[]  sigBytes = sgr.sign();        sgr.initVerify(vKey);        sgr.update(message);        if (!sgr.verify(sigBytes))        {            fail("239 Bit EC verification failed");        }        BigInteger[]  sig = derDecode(sigBytes);        if (!r.equals(sig[0]))        {            fail("r component wrong." + System.getProperty("line.separator")                + " expecting: " + r + System.getProperty("line.separator")                + " got      : " + sig[0]);        }        if (!s.equals(sig[1]))        {            fail("s component wrong." + System.getProperty("line.separator")                + " expecting: " + s + System.getProperty("line.separator")                + " got      : " + sig[1]);        }    }