java.security.spec.ECGenParameterSpec Java Examples

/**
 * Returns the ECPublicKey instance from its encoded raw bytes. 
 * The first byte has the fixed value 0x04 indicating the uncompressed form.
 * Therefore, the byte array must be of form: [0x04, x coord of point (32 bytes), y coord of point (32 bytes)]
 * 
 * @param publicKeyBytes The byte array representing the encoded raw bytes of the public key
 * @return The ECPublicKey instance
 */
public static ECPublicKey getPublicKey(byte[] publicKeyBytes) {
	// First we separate x and y of coordinates into separate variables
    byte[] x = new byte[32];
    byte[] y = new byte[32];
    System.arraycopy(publicKeyBytes, 1, x, 0, 32);
    System.arraycopy(publicKeyBytes, 33, y, 0, 32);
    
    try {
		KeyFactory kf = KeyFactory.getInstance("EC");
		
		AlgorithmParameters parameters = AlgorithmParameters.getInstance("EC");
		parameters.init(new ECGenParameterSpec("secp256r1"));
		ECParameterSpec ecParameterSpec = parameters.getParameterSpec(ECParameterSpec.class);
		
		ECPublicKeySpec ecPublicKeySpec = new ECPublicKeySpec(new ECPoint(new BigInteger(x), new BigInteger(y)), ecParameterSpec);
		ECPublicKey ecPublicKey = (ECPublicKey) kf.generatePublic(ecPublicKeySpec);
		return ecPublicKey;
    } catch (NoSuchAlgorithmException | InvalidParameterSpecException | InvalidKeySpecException e) {
		getLogger().error(e.getClass().getSimpleName() + " occurred when trying to get public key from raw bytes", e);
        return null;
	}
}
 

@Test
public void testFromJsonWebKey() throws Exception {
    ECGenParameterSpec gps = new ECGenParameterSpec(EcKey.P384);
    EC_KEY_GENERATOR.initialize(gps);
    KeyPair keyPair = EC_KEY_GENERATOR.generateKeyPair();
    
    ECPublicKey apub = (ECPublicKey) keyPair.getPublic();
    ECPoint point = apub.getW();
    ECPrivateKey apriv = (ECPrivateKey) keyPair.getPrivate();
    
    JsonWebKey jwk = new JsonWebKey()
            .withKid("kid")
            .withCrv(JsonWebKeyCurveName.P_384)
            .withX(point.getAffineX().toByteArray())
            .withY(point.getAffineY().toByteArray())
            .withD(apriv.getS().toByteArray())
            .withKty(JsonWebKeyType.EC);

    assertTrue(jwk.hasPrivateKey());
    
    EcKey newKey = EcKey.fromJsonWebKey(jwk, true);
    assertEquals("kid", newKey.getKid());
    doSignVerify(newKey, DIGEST_384);
}
 

private static boolean isAvailableCurve(int curveId) {
    String oid = idToOidMap.get(curveId);
    if (oid != null) {
        AlgorithmParameters params = null;
        try {
            params = JsseJce.getAlgorithmParameters("EC");
            params.init(new ECGenParameterSpec(oid));
        } catch (Exception e) {
            return false;
        }

        // cache the parameters
        idToParams.put(curveId, params);

        return true;
    }

    return false;
}
 

ECDHEPossession(NamedGroup namedGroup, SecureRandom random) {
    try {
        KeyPairGenerator kpg = JsseJce.getKeyPairGenerator("EC");
        ECGenParameterSpec params =
                (ECGenParameterSpec)namedGroup.getParameterSpec();
        kpg.initialize(params, random);
        KeyPair kp = kpg.generateKeyPair();
        privateKey = kp.getPrivate();
        publicKey = (ECPublicKey)kp.getPublic();
    } catch (GeneralSecurityException e) {
        throw new RuntimeException(
            "Could not generate ECDH keypair", e);
    }

    this.namedGroup = namedGroup;
}
 

private static boolean isAvailableCurve(int curveId) {
    String oid = idToOidMap.get(curveId);
    if (oid != null) {
        AlgorithmParameters params = null;
        try {
            params = JsseJce.getAlgorithmParameters("EC");
            params.init(new ECGenParameterSpec(oid));
        } catch (Exception e) {
            return false;
        }

        // cache the parameters
        idToParams.put(curveId, params);

        return true;
    }

    return false;
}
 

@Test
void gen() throws NoSuchAlgorithmException, InvalidAlgorithmParameterException {
    // 获取SM2椭圆曲线的参数
    final ECGenParameterSpec sm2Spec = new ECGenParameterSpec("sm2p256v1");
    // 获取一个椭圆曲线类型的密钥对生成器
    final KeyPairGenerator kpg = KeyPairGenerator.getInstance("EC", new BouncyCastleProvider());
    // 使用SM2参数初始化生成器
    kpg.initialize(sm2Spec);

    // 使用SM2的算法区域初始化密钥生成器
    kpg.initialize(sm2Spec, new SecureRandom());
    // 获取密钥对
    KeyPair keyPair = kpg.generateKeyPair();

    PublicKey pubKey = keyPair.getPublic();
    String pubKEnc = Base64.toBase64String(pubKey.getEncoded());
    System.out.println(">> Pub Key: " + pubKEnc);

    PrivateKey priKey = keyPair.getPrivate();
    String priKEnc = Base64.toBase64String(priKey.getEncoded());
    System.out.println(">> Pri Key: " + priKEnc);
}
 

/**
 * Generate a new ES256 keypair (COSE algorithm -7, ECDSA + SHA-256 over the NIST P-256 curve).
 *
 * @param alias The alias used to identify this keypair in the keystore. Needed to use key
 *              in the future.
 * @return The KeyPair object representing the newly generated keypair.
 * @throws VirgilException
 */
private KeyPair generateNewES256KeyPair(String alias) throws VirgilException {
    KeyGenParameterSpec spec = new KeyGenParameterSpec.Builder(alias, KeyProperties.PURPOSE_SIGN)
            .setAlgorithmParameterSpec(new ECGenParameterSpec(CURVE_NAME))
            .setDigests(KeyProperties.DIGEST_SHA256)
            .setUserAuthenticationRequired(this.authenticationRequired) // fingerprint or similar
            .setUserConfirmationRequired(false) // TODO: Decide if we support Android Trusted Confirmations
            .setInvalidatedByBiometricEnrollment(false)
            .setIsStrongBoxBacked(this.strongboxRequired)
            .build();
    try {
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(KeyProperties.KEY_ALGORITHM_EC, KEYSTORE_TYPE);
        keyPairGenerator.initialize(spec);
        KeyPair keyPair = keyPairGenerator.generateKeyPair();
        return keyPair;
    } catch (NoSuchAlgorithmException | NoSuchProviderException | InvalidAlgorithmParameterException e) {
        throw new VirgilException("couldn't generate key pair: " + e.toString());
    }
}
 

static ECGenParameterSpec getECGenParamSpec(NamedGroup namedGroup) {
    if (namedGroup.type != NamedGroupType.NAMED_GROUP_ECDHE) {
        throw new RuntimeException(
                "Not a named EC group: " + namedGroup);
    }

    AlgorithmParameters params = namedGroupParams.get(namedGroup);
    if (params == null) {
        throw new RuntimeException(
                "Not a supported EC named group: " + namedGroup);
    }

    try {
        return params.getParameterSpec(ECGenParameterSpec.class);
    } catch (InvalidParameterSpecException ipse) {
        // should be unlikely
        return new ECGenParameterSpec(namedGroup.oid);
    }
}
 

@Override
public void initialize(AlgorithmParameterSpec params, SecureRandom random)
        throws InvalidAlgorithmParameterException {

    if (params instanceof ECParameterSpec) {
        this.params = ECUtil.getECParameterSpec(null,
                                                (ECParameterSpec)params);
        if (this.params == null) {
            throw new InvalidAlgorithmParameterException(
                "Unsupported curve: " + params);
        }
    } else if (params instanceof ECGenParameterSpec) {
        String name = ((ECGenParameterSpec)params).getName();
        this.params = ECUtil.getECParameterSpec(null, name);
        if (this.params == null) {
            throw new InvalidAlgorithmParameterException(
                "Unknown curve name: " + name);
        }
    } else {
        throw new InvalidAlgorithmParameterException(
            "ECParameterSpec or ECGenParameterSpec required for EC");
    }
    this.keySize =
        ((ECParameterSpec)this.params).getCurve().getField().getFieldSize();
    this.random = random;
}
 

public void generateCA() throws NoSuchAlgorithmException, IOException, OperatorCreationException, InvalidAlgorithmParameterException {
    ECGenParameterSpec ecGenSpec = new ECGenParameterSpec("secp384k1");
    KeyPairGenerator generator = KeyPairGenerator.getInstance("EC");
    generator.initialize(ecGenSpec, SecurityHelper.newRandom());
    KeyPair pair = generator.generateKeyPair();
    LocalDateTime startDate = LocalDate.now().atStartOfDay();

    X500NameBuilder subject = new X500NameBuilder();
    subject.addRDN(BCStyle.CN, orgName.concat(" CA"));
    subject.addRDN(BCStyle.O, orgName);

    X509v3CertificateBuilder builder = new X509v3CertificateBuilder(
            subject.build(),
            new BigInteger("0"),
            Date.from(startDate.atZone(ZoneId.systemDefault()).toInstant()),
            Date.from(startDate.plusDays(3650).atZone(ZoneId.systemDefault()).toInstant()),
            new X500Name("CN=ca"),
            SubjectPublicKeyInfo.getInstance(pair.getPublic().getEncoded()));
    JcaContentSignerBuilder csBuilder = new JcaContentSignerBuilder("SHA256WITHECDSA");
    ContentSigner signer = csBuilder.build(pair.getPrivate());
    ca = builder.build(signer);
    caKey = PrivateKeyFactory.createKey(pair.getPrivate().getEncoded());
}
 

@Test
public void testEncryptDecrypt() throws Exception {

	final String name = "secp256r1";

	// NOTE just "EC" also seems to work here
	final KeyPairGenerator kpg = KeyPairGenerator.getInstance("ECDH", BouncyCastleProvider.PROVIDER_NAME);
	kpg.initialize(new ECGenParameterSpec(name));

	// Key pair to store public and private key
	final KeyPair keyPair = kpg.generateKeyPair();

	// Message to encrypt
	byte[] message = "hello".getBytes(StandardCharsets.UTF_8);

	// Encrypt
	final BigInteger r = EciesEncryption.generateR();
	byte[] encrypted = EciesEncryption.encrypt(message, r, keyPair.getPublic());

	// Decrypt
	byte[] decrypted = EciesEncryption.decrypt(encrypted, keyPair.getPrivate());
	System.out.println("Decrypted message: " + new String(decrypted));

	Assert.assertArrayEquals(message, decrypted);

}
 

/**
 * Get the EC curve parameters used by the secp256k1 keys used for HD seeds
 */
public static ECParameterSpec getECHDSpec()
{
  try
  {
    ECGenParameterSpec spec = new ECGenParameterSpec("secp256k1");
    KeyPairGenerator key_gen = KeyPairGenerator.getInstance("ECDSA", Globals.getCryptoProviderName());
    key_gen.initialize(spec);

    KeyPair pair = key_gen.genKeyPair();
    ECPrivateKey priv = (ECPrivateKey)pair.getPrivate();

    return priv.getParams();
  }
  catch(Exception e)
  {
    throw new RuntimeException(e);
  }

}
 

public static WalletKeyPair generateWalletDSTU4145Key(int curve)
{
  try
  {
    ECGenParameterSpec spec = new ECGenParameterSpec("1.2.804.2.1.1.1.1.3.1.1.2." + curve);

    KeyPairGenerator key_gen = KeyPairGenerator.getInstance("DSTU4145", Globals.getCryptoProviderName());

    key_gen.initialize(spec);
    KeyPair key_pair = key_gen.genKeyPair();

    WalletKeyPair wkp = WalletKeyPair.newBuilder()
      .setPublicKey(ByteString.copyFrom(key_pair.getPublic().getEncoded()))
      .setPrivateKey(ByteString.copyFrom(key_pair.getPrivate().getEncoded()))
      .setSignatureType(SignatureUtil.SIG_TYPE_DSTU4145)
      .build();
    return wkp;
  }
  catch(Exception e)
  {
    throw new RuntimeException(e);
  }
}
 

private KeyPair generateKeyPair(String keyName, boolean invalidatedByBiometricEnrollment) throws Exception {
    KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(KeyProperties.KEY_ALGORITHM_EC, "AndroidKeyStore");

    KeyGenParameterSpec.Builder builder = new KeyGenParameterSpec.Builder(keyName,
            KeyProperties.PURPOSE_SIGN)
            .setAlgorithmParameterSpec(new ECGenParameterSpec("secp256r1"))
            .setDigests(KeyProperties.DIGEST_SHA256,
                    KeyProperties.DIGEST_SHA384,
                    KeyProperties.DIGEST_SHA512)
            // Require the user to authenticate with a biometric to authorize every use of the key
            .setUserAuthenticationRequired(true);

    // Generated keys will be invalidated if the biometric templates are added more to user device
    if (Build.VERSION.SDK_INT >= 24) {
        builder.setInvalidatedByBiometricEnrollment(invalidatedByBiometricEnrollment);
    }

    keyPairGenerator.initialize(builder.build());

    return keyPairGenerator.generateKeyPair();
}
 

private static boolean isAvailableCurve(int curveId) {
    String oid = idToOidMap.get(curveId);
    if (oid != null) {
        AlgorithmParameters params = null;
        try {
            params = JsseJce.getAlgorithmParameters("EC");
            params.init(new ECGenParameterSpec(oid));
        } catch (Exception e) {
            return false;
        }

        // cache the parameters
        idToParams.put(curveId, params);

        return true;
    }

    return false;
}
 

@Test
public void testToJsonWebKey() throws Exception {
	ECGenParameterSpec gps = new ECGenParameterSpec(EcKey.P521);
	EC_KEY_GENERATOR.initialize(gps);
	KeyPair keyPair = EC_KEY_GENERATOR.generateKeyPair();
	
	ECPublicKey apub = (ECPublicKey) keyPair.getPublic();
	ECPoint point = apub.getW();
	ECPrivateKey apriv = (ECPrivateKey) keyPair.getPrivate();
	
	JsonWebKey jwk = new JsonWebKey()
			.withKid("kid")
			.withCrv(JsonWebKeyCurveName.P_521)
			.withX(point.getAffineX().toByteArray())
			.withY(point.getAffineY().toByteArray())
			.withD(apriv.getS().toByteArray())
			.withKty(JsonWebKeyType.EC);
	
	EcKey newKey = new EcKey("kid", keyPair);
	
	JsonWebKey newJwk = newKey.toJsonWebKey();
	//set missing parameters
	newJwk.withKid("kid");
	
	assertEquals(jwk, newJwk);	
}
 

/**
 * Returns the ECPrivateKey instance from its raw bytes. Note that you must provide the "s" value of the 
 * private key, not e.g. the byte array from reading a PKCS#8 key file.
 * 
 * @param privateKeyBytes The byte array (the "s" value) of the private key
 * @return The ECPrivateKey instance
 */
public static ECPrivateKey getPrivateKey(byte[] privateKeyBytes) {
	try {
		AlgorithmParameters parameters = AlgorithmParameters.getInstance("EC");
		parameters.init(new ECGenParameterSpec("secp256r1"));
		
		ECParameterSpec ecParameterSpec = parameters.getParameterSpec(ECParameterSpec.class);
		ECPrivateKeySpec ecPrivateKeySpec = new ECPrivateKeySpec(new BigInteger(privateKeyBytes), ecParameterSpec);
		
		ECPrivateKey privateKey = (ECPrivateKey) KeyFactory.getInstance("EC").generatePrivate(ecPrivateKeySpec);

		return privateKey;
	} catch (NoSuchAlgorithmException | InvalidKeySpecException | InvalidParameterSpecException e) {
		getLogger().error(e.getClass().getSimpleName() + " occurred when trying to get private key from raw bytes", e);
		return null;
	}
}
 

private static boolean isAvailableCurve(int curveId) {
    String oid = idToOidMap.get(curveId);
    if (oid != null) {
        AlgorithmParameters params = null;
        try {
            params = JsseJce.getAlgorithmParameters("EC");
            params.init(new ECGenParameterSpec(oid));
        } catch (Exception e) {
            return false;
        }

        // cache the parameters
        idToParams.put(curveId, params);

        return true;
    }

    return false;
}
 

@Override
public void initialize(AlgorithmParameterSpec params, SecureRandom random)
        throws InvalidAlgorithmParameterException {

    if (params instanceof ECParameterSpec) {
        this.params = ECUtil.getECParameterSpec(null,
                                                (ECParameterSpec)params);
        if (this.params == null) {
            throw new InvalidAlgorithmParameterException(
                "Unsupported curve: " + params);
        }
    } else if (params instanceof ECGenParameterSpec) {
        String name = ((ECGenParameterSpec)params).getName();
        this.params = ECUtil.getECParameterSpec(null, name);
        if (this.params == null) {
            throw new InvalidAlgorithmParameterException(
                "Unknown curve name: " + name);
        }
    } else {
        throw new InvalidAlgorithmParameterException(
            "ECParameterSpec or ECGenParameterSpec required for EC");
    }
    this.keySize =
        ((ECParameterSpec)this.params).getCurve().getField().getFieldSize();
    this.random = random;
}
 

private static boolean isAvailableCurve(int curveId) {
    String oid = idToOidMap.get(curveId);
    if (oid != null) {
        AlgorithmParameters params = null;
        try {
            params = JsseJce.getAlgorithmParameters("EC");
            params.init(new ECGenParameterSpec(oid));
        } catch (Exception e) {
            return false;
        }

        // cache the parameters
        idToParams.put(curveId, params);

        return true;
    }

    return false;
}
 

@Override
public void initialize(AlgorithmParameterSpec params, SecureRandom random)
        throws InvalidAlgorithmParameterException {

    if (params instanceof ECParameterSpec) {
        this.params = ECUtil.getECParameterSpec(null,
                                                (ECParameterSpec)params);
        if (this.params == null) {
            throw new InvalidAlgorithmParameterException(
                "Unsupported curve: " + params);
        }
    } else if (params instanceof ECGenParameterSpec) {
        String name = ((ECGenParameterSpec)params).getName();
        this.params = ECUtil.getECParameterSpec(null, name);
        if (this.params == null) {
            throw new InvalidAlgorithmParameterException(
                "Unknown curve name: " + name);
        }
    } else {
        throw new InvalidAlgorithmParameterException(
            "ECParameterSpec or ECGenParameterSpec required for EC");
    }
    this.keySize =
        ((ECParameterSpec)this.params).getCurve().getField().getFieldSize();
    this.random = random;
}
 

private static boolean isAvailableCurve(int curveId) {
    String oid = idToOidMap.get(curveId);
    if (oid != null) {
        AlgorithmParameters params = null;
        try {
            params = JsseJce.getAlgorithmParameters("EC");
            params.init(new ECGenParameterSpec(oid));
        } catch (Exception e) {
            return false;
        }

        // cache the parameters
        idToParams.put(curveId, params);

        return true;
    }

    return false;
}
 

@Override
public void initialize(AlgorithmParameterSpec params, SecureRandom random)
        throws InvalidAlgorithmParameterException {

    if (params instanceof ECParameterSpec) {
        this.params = ECUtil.getECParameterSpec(null,
                                                (ECParameterSpec)params);
        if (this.params == null) {
            throw new InvalidAlgorithmParameterException(
                "Unsupported curve: " + params);
        }
    } else if (params instanceof ECGenParameterSpec) {
        String name = ((ECGenParameterSpec)params).getName();
        this.params = ECUtil.getECParameterSpec(null, name);
        if (this.params == null) {
            throw new InvalidAlgorithmParameterException(
                "Unknown curve name: " + name);
        }
    } else {
        throw new InvalidAlgorithmParameterException(
            "ECParameterSpec or ECGenParameterSpec required for EC");
    }
    this.keySize =
        ((ECParameterSpec)this.params).getCurve().getField().getFieldSize();
    this.random = random;
}
 

/**
 * Constructor.
 * 
 * Generates a new EcKey with the given curve and kid.
 * @param kid
 * @param curve
 * @param provider Java security provider
 * @throws InvalidAlgorithmParameterException
 * @throws NoSuchAlgorithmException
 */
public EcKey(String kid, JsonWebKeyCurveName curve, Provider provider) throws InvalidAlgorithmParameterException, NoSuchAlgorithmException {
	_kid = kid;
	_provider = provider;
	_curve = curve;
	
	_signatureAlgorithm = CURVE_TO_SIGNATURE.get(curve);
	if (_signatureAlgorithm == null) {
		throw new NoSuchAlgorithmException("Curve not supported.");
	}
	
	final KeyPairGenerator generator = KeyPairGenerator.getInstance("EC", provider);
	ECGenParameterSpec gps = new ECGenParameterSpec(CURVE_TO_SPEC_NAME.get(curve));

	generator.initialize(gps);
	_keyPair = generator.generateKeyPair();
	
}
 

@Test(expected = UnsupportedOperationException.class)
public void testFromJsonWebKeyPublicOnly() throws Exception {
	ECGenParameterSpec gps = new ECGenParameterSpec(EcKey.P256);
	EC_KEY_GENERATOR.initialize(gps);
	KeyPair keyPair = EC_KEY_GENERATOR.generateKeyPair();
	
	ECPublicKey apub = (ECPublicKey) keyPair.getPublic();
	ECPoint point = apub.getW();
	
	JsonWebKey jwk = new JsonWebKey()
			.withKid("kid")
			.withCrv(JsonWebKeyCurveName.P_256)
			.withX(point.getAffineX().toByteArray())
			.withY(point.getAffineY().toByteArray())
			.withKty(JsonWebKeyType.EC);

	assertFalse(jwk.hasPrivateKey());
	
	EcKey newKey = EcKey.fromJsonWebKey(jwk, false);
	assertEquals("kid", newKey.getKid());
	doSignVerify(newKey, DIGEST_256);
}
 

/**
 *
 * @param publickeybytes
 * @return
 * @throws java.security.spec.InvalidKeySpecException
 * @throws java.security.NoSuchAlgorithmException
 * @throws java.security.NoSuchProviderException
 * @throws java.security.spec.InvalidParameterSpecException
 */
public static ECPublicKey getUserECPublicKey(byte[] publickeybytes) throws InvalidKeySpecException, NoSuchAlgorithmException, NoSuchProviderException, InvalidParameterSpecException {

    //append the sign byte to the arrays
    byte[] processedXData = new byte[EC_POINTSIZE];
    byte[] processedYData = new byte[EC_POINTSIZE];
    System.arraycopy(publickeybytes, 1, processedXData, 0, EC_POINTSIZE);
    System.arraycopy(publickeybytes, EC_POINTSIZE + 1, processedYData, 0, EC_POINTSIZE);

    ECPoint pubPoint = new ECPoint(new BigInteger(1, processedXData), new BigInteger(1, processedYData));
    AlgorithmParameters params = AlgorithmParameters.getInstance("EC", BC_FIPS_PROVIDER);
    params.init(new ECGenParameterSpec("prime256v1"));
    ECParameterSpec ecParameters = params.getParameterSpec(ECParameterSpec.class);
    ECPublicKeySpec pubECSpec = new ECPublicKeySpec(pubPoint, ecParameters);
    return (ECPublicKey) KeyFactory.getInstance("EC", BC_FIPS_PROVIDER).generatePublic(pubECSpec);
}
 

static ECGenParameterSpec getECGenParamSpec(int index) {
    AlgorithmParameters params = idToParams.get(index);
    try {
        return params.getParameterSpec(ECGenParameterSpec.class);
    } catch (InvalidParameterSpecException ipse) {
        // should be unlikely
        String curveOid = getCurveOid(index);
        return new ECGenParameterSpec(curveOid);
    }
}
 

private static void startEncryptionHandshake(GeyserSession session, PublicKey key) throws Exception {
    KeyPairGenerator generator = KeyPairGenerator.getInstance("EC");
    generator.initialize(new ECGenParameterSpec("secp384r1"));
    KeyPair serverKeyPair = generator.generateKeyPair();

    byte[] token = EncryptionUtils.generateRandomToken();
    SecretKey encryptionKey = EncryptionUtils.getSecretKey(serverKeyPair.getPrivate(), key, token);
    session.getUpstream().getSession().enableEncryption(encryptionKey);

    ServerToClientHandshakePacket packet = new ServerToClientHandshakePacket();
    packet.setJwt(EncryptionUtils.createHandshakeJwt(serverKeyPair, token).serialize());
    session.sendUpstreamPacketImmediately(packet);
}
 

public static KeyPair generateKeyPair() {
  try {
    ECGenParameterSpec spec = new ECGenParameterSpec("secp256r1");
    KeyPairGenerator gen = KeyPairGenerator.getInstance("EC");
    gen.initialize(spec);
    KeyPair keyPair = gen.generateKeyPair();
    return keyPair;
  } catch (NoSuchAlgorithmException | InvalidAlgorithmParameterException e) {
    throw new RuntimeException(e);
  }
}
 

private static ECParameterSpec createECParameterSpec(String stdName) {
  try {
    final KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("EC");
    final ECGenParameterSpec parameterSpec = new ECGenParameterSpec(stdName);
    keyPairGenerator.initialize(parameterSpec);
    final KeyPair keyPair = keyPairGenerator.generateKeyPair();
    final ECPublicKey publicKey = (ECPublicKey) keyPair.getPublic();
    return publicKey.getParams();
  } catch (GeneralSecurityException cause) {
    throw new RuntimeException(cause);
  }
}