Java Code Examples for org.bouncycastle.crypto.params.ECDomainParameters#getN()

public static KeyPair generateKeyPair(ECDomainParameters domainParameters, SecureRandom random)
        throws NoSuchProviderException, NoSuchAlgorithmException,
        InvalidAlgorithmParameterException {
    KeyPairGenerator kpg = KeyPairGenerator.getInstance(ALGO_NAME_EC, BouncyCastleProvider.PROVIDER_NAME);
    ECParameterSpec parameterSpec = new ECParameterSpec(domainParameters.getCurve(), domainParameters.getG(),
            domainParameters.getN(), domainParameters.getH());
    kpg.initialize(parameterSpec, random);
    return kpg.generateKeyPair();
}
 

/**
 * 将ECC公钥对象转换为X509标准的字节流
 *
 * @param pubKey
 * @return
 */
public static byte[] convertECPublicKeyToX509(ECPublicKeyParameters pubKey) {
    ECDomainParameters domainParams = pubKey.getParameters();
    ECParameterSpec spec = new ECParameterSpec(domainParams.getCurve(), domainParams.getG(),
            domainParams.getN(), domainParams.getH());
    BCECPublicKey publicKey = new BCECPublicKey(ALGO_NAME_EC, pubKey, spec,
            BouncyCastleProvider.CONFIGURATION);
    return publicKey.getEncoded();
}
 

public Sm2KeyPairImpl(boolean selfgen) {
	SecureRandom random = new SecureRandom();
	ECKeyGenerationParameters keyGenerationParams = new ECKeyGenerationParameters(DOMAIN_PARAMS, random);
	ECKeyPairGenerator keyGen = new ECKeyPairGenerator();
	keyGen.init(keyGenerationParams);
	AsymmetricCipherKeyPair keyPair = keyGen.generateKeyPair();
	ECPrivateKeyParameters priKey = (ECPrivateKeyParameters) keyPair.getPrivate();
	ECPublicKeyParameters pubKey = (ECPublicKeyParameters) keyPair.getPublic();
	ECDomainParameters domainParams = priKey.getParameters();
	ECParameterSpec spec = new ECParameterSpec(domainParams.getCurve(), domainParams.getG(), domainParams.getN(),
			domainParams.getH());
	BCECPublicKey bcecPublicKey = new BCECPublicKey(ALGO_NAME_EC, pubKey, spec, BouncyCastleProvider.CONFIGURATION);
	publicKey = new Sm2PublicKeyImpl(bcecPublicKey);
	privateKey = new Sm2PrivateKeyImpl(new BCECPrivateKey(ALGO_NAME_EC, priKey, bcecPublicKey, spec, BouncyCastleProvider.CONFIGURATION));
}
 

public static byte[] convertEcPubKeyToX509Der(ECPublicKeyParameters pubKey) {
    ECDomainParameters domainParams = pubKey.getParameters();
    ECParameterSpec spec = new ECParameterSpec(domainParams.getCurve(), domainParams.getG(),
        domainParams.getN(), domainParams.getH());
    BCECPublicKey publicKey = new BCECPublicKey(ALGO_NAME_EC, pubKey, spec,
        BouncyCastleProvider.CONFIGURATION);
    return publicKey.getEncoded();
}
 

/**
 * return true if the value r and s represent a DSA signature for the passed in
 * message (for standard DSA the message should be a SHA-1 hash of the real
 * message to be verified).
 */
@Override
public boolean verifySignature(byte[] message, BigInteger r, BigInteger s) {
    ECDomainParameters ec = key.getParameters();
    BigInteger n = ec.getN();
    BigInteger e = calculateE(n, message);

    // r in the range [1,n-1]
    if (r.compareTo(ONE) < 0 || r.compareTo(n) >= 0) {
        return false;
    }

    // s in the range [1,n-1]
    if (s.compareTo(ONE) < 0 || s.compareTo(n) >= 0) {
        return false;
    }

    BigInteger c = s.modInverse(n);

    BigInteger u1 = e.multiply(c).mod(n);
    BigInteger u2 = r.multiply(c).mod(n);

    ECPoint G = ec.getG();
    ECPoint Q = ((ECPublicKeyParameters) key).getQ();

    ECPoint point = ECAlgorithms.sumOfTwoMultiplies(G, u1, Q, u2).normalize();

    // components must be bogus.
    if (point.isInfinity()) {
        return false;
    }

    BigInteger v = point.getAffineXCoord().toBigInteger().mod(n);

    return v.equals(r);
}
 

/**
 * generate a signature for the given message using the key we were initialised with. For
 * conventional DSA the message should be a SHA-1 hash of the message of interest.
 *
 * @param message the message that will be verified later.
 */
@Override
public BigInteger[] generateSignature(byte[] message) {
    ECDomainParameters ec = key.getParameters();
    BigInteger n = ec.getN();
    BigInteger e = calculateE(n, message);
    BigInteger d = ((ECPrivateKeyParameters) key).getD();

    if (kCalculator.isDeterministic()) {
        kCalculator.init(n, d, message);
    } else {
        kCalculator.init(n, random);
    }

    BigInteger r, s;

    ECMultiplier basePointMultiplier = createBasePointMultiplier();

    // 5.3.2
    do // generate s
    {
        BigInteger k;
        do // generate r
        {
            k = kCalculator.nextK();

            ECPoint p = basePointMultiplier.multiply(ec.getG(), k).normalize();

            // 5.3.3
            r = p.getAffineXCoord().toBigInteger().mod(n);
        } while (r.equals(ZERO));

        s = k.modInverse(n).multiply(e.add(d.multiply(r))).mod(n);
    } while (s.equals(ZERO));

    return new BigInteger[] {r, s};
}
 

/**
 * The same generateSignature with the temporary variable ECPoint P generated by the signature
 * process is also returned together
 *
 * @param message the message that will be verified later.
 */
public Object[] generateSignature2(byte[] message) {
    ECDomainParameters ec = key.getParameters();
    BigInteger n = ec.getN();
    BigInteger e = calculateE(n, message);
    BigInteger d = ((ECPrivateKeyParameters) key).getD();

    if (kCalculator.isDeterministic()) {
        kCalculator.init(n, d, message);
    } else {
        kCalculator.init(n, random);
    }

    BigInteger r, s;

    /** */
    ECPoint p;

    ECMultiplier basePointMultiplier = createBasePointMultiplier();

    // 5.3.2
    do // generate s
    {
        BigInteger k;
        do // generate r
        {
            k = kCalculator.nextK();

            p = basePointMultiplier.multiply(ec.getG(), k).normalize();

            // 5.3.3
            r = p.getAffineXCoord().toBigInteger().mod(n);
        } while (r.equals(ZERO));

        s = k.modInverse(n).multiply(e.add(d.multiply(r))).mod(n);
    } while (s.equals(ZERO));

    return new Object[] {r, s, p};
}
 

public static KeyPair generateKeyPair(ECDomainParameters domainParameters, SecureRandom random)
    throws NoSuchProviderException, NoSuchAlgorithmException,
    InvalidAlgorithmParameterException {
    KeyPairGenerator kpg = KeyPairGenerator.getInstance(ALGO_NAME_EC, BouncyCastleProvider.PROVIDER_NAME);
    ECParameterSpec parameterSpec = new ECParameterSpec(domainParameters.getCurve(), domainParameters.getG(),
        domainParameters.getN(), domainParameters.getH());
    kpg.initialize(parameterSpec, random);
    return kpg.generateKeyPair();
}
 

/**
 * 将ECC公钥对象转换为X509标准的字节流
 *
 * @param pubKey
 * @return
 */
public static byte[] convertECPublicKeyToX509(ECPublicKeyParameters pubKey) {
    ECDomainParameters domainParams = pubKey.getParameters();
    ECParameterSpec spec = new ECParameterSpec(domainParams.getCurve(), domainParams.getG(),
        domainParams.getN(), domainParams.getH());
    BCECPublicKey publicKey = new BCECPublicKey(ALGO_NAME_EC, pubKey, spec,
        BouncyCastleProvider.CONFIGURATION);
    return publicKey.getEncoded();
}
 

/**
 * generate a signature for the given message using the key we were initialised
 * with. For conventional DSA the message should be a SHA-1 hash of the message
 * of interest.
 *
 * @param message
 *                    the message that will be verified later.
 */
@Override
public BigInteger[] generateSignature(byte[] message) {
    ECDomainParameters ec = key.getParameters();
    BigInteger n = ec.getN();
    BigInteger e = calculateE(n, message);
    BigInteger d = ((ECPrivateKeyParameters) key).getD();

    if (kCalculator.isDeterministic()) {
        kCalculator.init(n, d, message);
    } else {
        kCalculator.init(n, random);
    }

    BigInteger r, s;

    ECMultiplier basePointMultiplier = createBasePointMultiplier();

    int sLen = 0;
    // 5.3.2
    do // generate s
    {
        BigInteger k;
        int rLen = 0;
        do // generate r
        {
            k = kCalculator.nextK();

            ECPoint p = basePointMultiplier.multiply(ec.getG(), k).normalize();

            // 5.3.3
            r = p.getAffineXCoord().toBigInteger().mod(n);
            rLen = r.toByteArray().length;
        } while (r.equals(ZERO) || rLen != 32); // make sure that length of r is 32 bytes

        s = k.modInverse(n).multiply(e.add(d.multiply(r))).mod(n);
        sLen = s.toByteArray().length;
    } while (s.equals(ZERO) || sLen != 32);

    return new BigInteger[] { r, s };
}
 

/**
 * return true if the value r and s represent a DSA signature for the passed in message (for
 * standard DSA the message should be a SHA-1 hash of the real message to be verified).
 */
@Override
public boolean verifySignature(byte[] message, BigInteger r, BigInteger s) {
    ECDomainParameters ec = key.getParameters();
    BigInteger n = ec.getN();
    BigInteger e = calculateE(n, message);

    // r in the range [1,n-1]
    if (r.compareTo(ONE) < 0 || r.compareTo(n) >= 0) {
        return false;
    }

    // s in the range [1,n-1]
    if (s.compareTo(ONE) < 0 || s.compareTo(n) >= 0) {
        return false;
    }

    BigInteger c = s.modInverse(n);

    BigInteger u1 = e.multiply(c).mod(n);
    BigInteger u2 = r.multiply(c).mod(n);

    ECPoint G = ec.getG();
    ECPoint Q = ((ECPublicKeyParameters) key).getQ();

    ECPoint point = ECAlgorithms.sumOfTwoMultiplies(G, u1, Q, u2);

    // components must be bogus.
    if (point.isInfinity()) {
        return false;
    }

    /*
     * If possible, avoid normalizing the point (to save a modular inversion in the curve field).
     *
     * There are ~cofactor elements of the curve field that reduce (modulo the group order) to 'r'.
     * If the cofactor is known and small, we generate those possible field values and project each
     * of them to the same "denominator" (depending on the particular projective coordinates in use)
     * as the calculated point.X. If any of the projected values matches point.X, then we have:
     *     (point.X / Denominator mod p) mod n == r
     * as required, and verification succeeds.
     *
     * Based on an original idea by Gregory Maxwell (https://github.com/gmaxwell), as implemented in
     * the libsecp256k1 project (https://github.com/bitcoin/secp256k1).
     */
    ECCurve curve = point.getCurve();
    if (curve != null) {
        BigInteger cofactor = curve.getCofactor();
        if (cofactor != null && cofactor.compareTo(EIGHT) <= 0) {
            ECFieldElement D = getDenominator(curve.getCoordinateSystem(), point);
            if (D != null && !D.isZero()) {
                ECFieldElement X = point.getXCoord();
                while (curve.isValidFieldElement(r)) {
                    ECFieldElement R = curve.fromBigInteger(r).multiply(D);
                    if (R.equals(X)) {
                        return true;
                    }
                    r = r.add(n);
                }
                return false;
            }
        }
    }

    BigInteger v = point.normalize().getAffineXCoord().toBigInteger().mod(n);
    return v.equals(r);
}
 

/**
 * Calculates the sent address of an EthereumTransaction. Note this can be a costly operation to calculate. . This requires that you have Bouncy castle as a dependency in your project
 *
 *
 * @param eTrans transaction
 * @param chainId chain identifier (e.g. 1 main net)
 * @return sent address as byte array
 */
public static byte[] getSendAddress(EthereumTransaction eTrans, int chainId) {
	// init, maybe we move this out to save time
	X9ECParameters params = SECNamedCurves.getByName("secp256k1");
	ECDomainParameters CURVE=new ECDomainParameters(params.getCurve(), params.getG(), params.getN(), params.getH());	 // needed for getSentAddress

 
    byte[] transactionHash;

    if ((eTrans.getSig_v()[0]==chainId*2+EthereumUtil.CHAIN_ID_INC) || (eTrans.getSig_v()[0]==chainId*2+EthereumUtil.CHAIN_ID_INC+1)) {  // transaction hash with dummy signature data
    	 transactionHash = EthereumUtil.getTransactionHashWithDummySignatureEIP155(eTrans);
    } else {  // transaction hash without signature data
	 transactionHash = EthereumUtil.getTransactionHashWithoutSignature(eTrans);
    }
  // signature to address
	BigInteger bR = new BigInteger(1,eTrans.getSig_r());
	BigInteger bS = new BigInteger(1,eTrans.getSig_s());
  // calculate v for signature
	byte v =(byte) (eTrans.getSig_v()[0]);
	if (!((v == EthereumUtil.LOWER_REAL_V) || (v== (LOWER_REAL_V+1)))) {
		byte vReal = EthereumUtil.LOWER_REAL_V;
		if (((int)v%2 == 0)) {
			v = (byte) (vReal+0x01);
		} else {
			v = vReal;
		}
	}


	// the following lines are inspired from ECKey.java of EthereumJ, but adapted to the hadoopcryptoledger context
	if (v < 27 || v > 34) {
		LOG.error("Header out of Range:  "+v);
		throw new RuntimeException("Header out of range "+v);
	}
	if (v>=31) {

		v -=4;
	}
	int receiverId = v - 27;
	BigInteger n = CURVE.getN();
    BigInteger i = BigInteger.valueOf((long) receiverId / 2);
    BigInteger x = bR.add(i.multiply(n));
    ECCurve.Fp curve = (ECCurve.Fp) CURVE.getCurve();
    BigInteger prime = curve.getQ();
    if (x.compareTo(prime) >= 0) {
        return null;
     }
    // decompress Key
    X9IntegerConverter x9 = new X9IntegerConverter();
    byte[] compEnc = x9.integerToBytes(x, 1 + x9.getByteLength(CURVE.getCurve()));
    boolean yBit=(receiverId & 1) == 1;
    compEnc[0] = (byte)(yBit ? 0x03 : 0x02);
    ECPoint R =  CURVE.getCurve().decodePoint(compEnc);
    if (!R.multiply(n).isInfinity()) {
    		return null;
    }
    BigInteger e = new BigInteger(1,transactionHash);
    BigInteger eInv = BigInteger.ZERO.subtract(e).mod(n);
    BigInteger rInv = bR.modInverse(n);
    BigInteger srInv = rInv.multiply(bS).mod(n);
    BigInteger eInvrInv = rInv.multiply(eInv).mod(n);
    ECPoint.Fp q = (ECPoint.Fp) ECAlgorithms.sumOfTwoMultiplies(CURVE.getG(), eInvrInv, R, srInv);
    byte[] pubKey=q.getEncoded(false);
    // now we need to convert the public key into an ethereum send address which is the last 20 bytes of 32 byte KECCAK-256 Hash of the key.
	Keccak.Digest256 digest256 = new Keccak.Digest256();
	digest256.update(pubKey,1,pubKey.length-1);
	byte[] kcck = digest256.digest();
    return Arrays.copyOfRange(kcck,12,kcck.length);
}