Java ECParameterSpec.getGenerator方法代码示例

import java.security.spec.ECParameterSpec; //导入方法依赖的package包/类
private static ECParameterSpec mapNonceGMWithECDH(final BigInteger nonceS,
		                                          final ECPoint sharedSecretPointH,
		                                          final ECParameterSpec params) {
	// D~ = (p, a, b, G~, n, h) where G~ = [s]G + H
	final ECPoint generator = params.getGenerator();
	final EllipticCurve curve = params.getCurve();
	final BigInteger a = curve.getA();
	final BigInteger b = curve.getB();
	final ECFieldFp field = (ECFieldFp)curve.getField();
	final BigInteger p = field.getP();
	final BigInteger order = params.getOrder();
	final int cofactor = params.getCofactor();
	final ECPoint ephemeralGenerator = add(multiply(nonceS, generator, params), sharedSecretPointH, params);
	if (!toBouncyCastleECPoint(ephemeralGenerator, params).isValid()) {
		LOGGER.warning("Se ha generado un punto invalido"); //$NON-NLS-1$
	}
	return new ECParameterSpec(new EllipticCurve(new ECFieldFp(p), a, b), ephemeralGenerator, order, cofactor);
}
 

import java.security.spec.ECParameterSpec; //导入方法依赖的package包/类
private static ECParameterSpec mapNonceGMWithECDH(final BigInteger nonceS,
		                                          final ECPoint sharedSecretPointH,
		                                          final ECParameterSpec params) {
	// D~ = (p, a, b, G~, n, h) where G~ = [s]G + H
	final ECPoint generator = params.getGenerator();
	final EllipticCurve curve = params.getCurve();
	final BigInteger a = curve.getA();
	final BigInteger b = curve.getB();
	final ECFieldFp field = (ECFieldFp)curve.getField();
	final BigInteger p = field.getP();
	final BigInteger order = params.getOrder();
	final int cofactor = params.getCofactor();
	final ECPoint ephemeralGenerator = add(multiply(nonceS, generator, params), sharedSecretPointH, params);
	if (!toSpongyCastleECPoint(ephemeralGenerator, params).isValid()) {
		LOGGER.warning("Se ha generado un punto invalido"); //$NON-NLS-1$
	}
	return new ECParameterSpec(new EllipticCurve(new ECFieldFp(p), a, b), ephemeralGenerator, order, cofactor);
}
 

import java.security.spec.ECParameterSpec; //导入方法依赖的package包/类
/**
 * Checks if the private key is a valid key (according to requirement [V2G2-823]) for the received contract 
 * certificate before saving it to the keystore.
 * @param privateKey The private key corresponding to the contract certificate
 * @param contractCertChain The received contract certificate chain 
 * @return True, if the private key is a valid key, false otherwise.
 */
private static boolean isPrivateKeyValid(ECPrivateKey privateKey, CertificateChainType contractCertChain) {
	AlgorithmParameters parameters;
	
	try {
		parameters = AlgorithmParameters.getInstance("EC");
		parameters.init(new ECGenParameterSpec("secp256r1"));
		
		ECParameterSpec ecParameterSpec = parameters.getParameterSpec(ECParameterSpec.class);
		
		// Now we need to check if the private key is correct (see requirement [V2G2-823]) 
		BigInteger order = ecParameterSpec.getOrder();
		ECPoint basePoint = ecParameterSpec.getGenerator();
		BigInteger privateKeyValue = privateKey.getS();
		X509Certificate contractCert = getCertificate(contractCertChain.getCertificate());
		ECPublicKey publicKey = (ECPublicKey) contractCert.getPublicKey();
		
		// 1. check
		if (privateKeyValue.compareTo(order) != -1) {
			getLogger().error("Validation of private key failed: its value is not strictly smaller than the "
							+ "order of the base point");
			return false;
		}
		
		// 2. check
		/*
		 * TODO: 
		 * No idea how to check for 
		 * "multiplication of the base point with this value must generate a key matching the public key of 
		 * the contract certificate"
		 * "this value" = value of private key
		 * -> some more expert knowledge on the arithmetic of elliptic curves is needed to tackle this!
		 */
		
	} catch (NoSuchAlgorithmException | InvalidParameterSpecException e) {
		getLogger().error(e.getClass().getSimpleName() + " occurred when trying to get private key from raw bytes", e);
		return false;
	}
	
	return true;
}
 

import java.security.spec.ECParameterSpec; //导入方法依赖的package包/类
private static boolean Verify(ECParameterSpec spec, byte[] id, byte[] msg, ECPoint pkey, Sm2Signature sig) {

		do {
			// 第一步 r在[1,n-1]范围
			BigInteger order = spec.getOrder();
			if (sig.r.compareTo(order) >= 0 || sig.r.compareTo(BigInteger.ONE) < 0) {
				break;
			}

			// 第一步 s在[1,n-1]范围
			if (sig.s.compareTo(order) >= 0 || sig.s.compareTo(BigInteger.ONE) < 0) {
				break;
			}

			// 第三步 计算M^ = ZA||M
			byte[] ZA = GetZA(spec, pkey, id);
			byte[] M = new byte[ZA.length + msg.length];
			System.arraycopy(ZA, 0, M, 0, ZA.length);
			System.arraycopy(msg, 0, M, 32, msg.length);

			// 第四步 计算e=Hv(M^)
			byte[] stre = SM3Digest.Hash(M);
			BigInteger e = new BigInteger(bytesToHex(stre), 16);

			// 第五步 计算t=(r'+s')mod n
			BigInteger t = sig.r.add(sig.s).mod(order);
			if (t.compareTo(BigInteger.ZERO) == 0) {
				break;
			}

			// 第六步 计算(x1,y1) = [s]G + [t]PA
			ECPoint G = spec.getGenerator();
			ECPoint tmp1 = PointMul(sig.s, G, spec.getCurve());
			ECPoint tmp2 = PointMul(t, pkey, spec.getCurve());
			ECPoint tmPoint = PointAdd(tmp1, tmp2, spec.getCurve());

			// 第七步 R=(e' + x1') 验证R==r'?
			BigInteger R = e.add(tmPoint.getAffineX()).mod(order);
			if (R.compareTo(sig.r) != 0) {
				break;
			}

			return true;

		} while (false);
		return false;
	}