import org.spongycastle.jce.spec.ECParameterSpec; //导入依赖的package包/类
@Override
public boolean isSignatureValid(byte[] data, byte[] signature, Pubkey pubkey) {
    try {
        ECParameterSpec spec = new ECParameterSpec(
            EC_CURVE_PARAMETERS.getCurve(),
            EC_CURVE_PARAMETERS.getG(),
            EC_CURVE_PARAMETERS.getN(),
            EC_CURVE_PARAMETERS.getH(),
            EC_CURVE_PARAMETERS.getSeed()
        );

        ECPoint Q = keyToPoint(pubkey.getSigningKey());
        KeySpec keySpec = new ECPublicKeySpec(Q, spec);
        PublicKey publicKey = KeyFactory.getInstance(ALGORITHM_ECDSA, provider).generatePublic(keySpec);

        Signature sig = Signature.getInstance(ALGORITHM_ECDSA, provider);
        sig.initVerify(publicKey);
        sig.update(data);
        return sig.verify(signature);
    } catch (GeneralSecurityException e) {
        throw new ApplicationException(e);
    }
}
 

import org.spongycastle.jce.spec.ECParameterSpec; //导入依赖的package包/类
@Override
public byte[] getSignature(byte[] data, PrivateKey privateKey) {
    try {
        ECParameterSpec spec = new ECParameterSpec(
            EC_CURVE_PARAMETERS.getCurve(),
            EC_CURVE_PARAMETERS.getG(),
            EC_CURVE_PARAMETERS.getN(),
            EC_CURVE_PARAMETERS.getH(),
            EC_CURVE_PARAMETERS.getSeed()
        );

        BigInteger d = keyToBigInt(privateKey.getPrivateSigningKey());
        KeySpec keySpec = new ECPrivateKeySpec(d, spec);
        java.security.PrivateKey privKey = KeyFactory.getInstance(ALGORITHM_ECDSA, provider)
            .generatePrivate(keySpec);

        Signature sig = Signature.getInstance(ALGORITHM_ECDSA, provider);
        sig.initSign(privKey);
        sig.update(data);
        return sig.sign();
    } catch (GeneralSecurityException e) {
        throw new ApplicationException(e);
    }
}
 

import org.spongycastle.jce.spec.ECParameterSpec; //导入依赖的package包/类
/**
 * Creates a new (elliptic curve) KeyPair according to the given arguments.
 * @param curveName The given curnename
 * @param algorithm The used algorithm
 * @param provider The security provider
 * @param custom If this is a custom curve (see BouncyCastle for what custom curves are).
 * @return The generated keypair.
 */
public static KeyPair createNewKeyPair(String curveName, String algorithm, String provider, boolean custom) {
    ECParameterSpec ecSpec = getParameterSpec(curveName, custom);
    KeyPair keyPair = null;
    try {
        KeyPairGenerator g = KeyPairGenerator.getInstance(algorithm, provider);
        g.initialize(ecSpec, new SecureRandom());
        keyPair = g.generateKeyPair();
    } catch (Exception e) {
        e.printStackTrace();
    }
    return keyPair;
}
 

import org.spongycastle.jce.spec.ECParameterSpec; //导入依赖的package包/类
/**
 * Retrieves the parameters of the given elliptic curve.
 * @param curveName The curve name
 * @param custom Custom or not?
 * @return The elliptic curve parameters.
 */
private static ECParameterSpec getParameterSpec(String curveName, boolean custom) {
    if(custom) {
        X9ECParameters ecP = CustomNamedCurves.getByName(curveName);
        return new ECParameterSpec(ecP.getCurve(), ecP.getG(),
                ecP.getN(), ecP.getH(), ecP.getSeed());

    }
    return ECNamedCurveTable.getParameterSpec(curveName);
}
 

import org.spongycastle.jce.spec.ECParameterSpec; //导入依赖的package包/类
public static KeyPair generate () throws NoSuchAlgorithmException, InvalidAlgorithmParameterException {
    SecureRandom random = new SecureRandom();
    ECParameterSpec ecSpec = ECNamedCurveTable.getParameterSpec("secp256r1");
    KeyPairGenerator g = KeyPairGenerator.getInstance("ECDSA");
    g.initialize(ecSpec, random);
    return g.generateKeyPair();
}
 

import org.spongycastle.jce.spec.ECParameterSpec; //导入依赖的package包/类
public static KeyPair generate() throws NoSuchAlgorithmException, InvalidAlgorithmParameterException {
    SecureRandom random = new SecureRandom();
    ECParameterSpec ecSpec = ECNamedCurveTable.getParameterSpec("secp256r1");
    KeyPairGenerator g = KeyPairGenerator.getInstance("ECDSA");
    g.initialize(ecSpec, random);
    return g.generateKeyPair();
}
 

import org.spongycastle.jce.spec.ECParameterSpec; //导入依赖的package包/类
private static KeyPair generateNewKey(String spec) {
	try {
		ECParameterSpec ecSpec = ECNamedCurveTable.getParameterSpec(spec);
		KeyPairGenerator keyGen = KeyPairGenerator.getInstance("ECDSA", "SC");
		keyGen.initialize(ecSpec, new SecureRandom());
		return keyGen.generateKeyPair();
	} catch (Exception e) {
		Log.e(TAG, "error", e);
		System.exit(0);
		return null;
	}
}
 

import org.spongycastle.jce.spec.ECParameterSpec; //导入依赖的package包/类
private static long createECCKeys(String spec) throws NoSuchAlgorithmException, NoSuchProviderException, InvalidAlgorithmParameterException {
	long start = System.currentTimeMillis();
	
	ECParameterSpec ecSpec = ECNamedCurveTable.getParameterSpec(spec);
       KeyPairGenerator g = KeyPairGenerator.getInstance("ECDSA");
       g.initialize(ecSpec, new SecureRandom());
       g.generateKeyPair();
	
	return (System.currentTimeMillis() - start);
}
 

import org.spongycastle.jce.spec.ECParameterSpec; //导入依赖的package包/类
public static KeyPair generateKeyPair(PKIAlgorithm algorithm) throws UnknownPKIAlgorithmException,
        NoSuchAlgorithmException, NoSuchProviderException, InvalidAlgorithmParameterException {
	if (algorithm.getCode() != PKIAlgorithm.DEFAULT.getCode())
		throw new UnknownPKIAlgorithmException();

	ECParameterSpec ecSpec = ECNamedCurveTable.getParameterSpec(algorithm.getKeyPairSpecification());
	KeyPairGenerator keyGen = KeyPairGenerator.getInstance(algorithm.getKeyPairAlgorithm(), SECURITY_PROVIDER);
	keyGen.initialize(ecSpec, new SecureRandom());
	return keyGen.generateKeyPair();
}