Java Code Examples for org.bouncycastle.math.ec.ECPoint#multiply()

public KeyPair generateKeyPair(String privKey) {
    SM2PrivateKey privateKey = new SM2PrivateKey(new BigInteger(privKey, 16));
    byte[] privateKeyBytes = privateKey.getEncoded();
    privateKey.setD(new BigInteger(Hex.toHexString(privateKeyBytes), 16));
    try {
        ECPoint g = ecdp.getG();
        ECPoint p = g.multiply(privateKey.getD());
        // System.out.println("===d:" + privateKey.getD().toString(16));
        SM2PublicKey publicKey = new SM2PublicKey(p);
        return new KeyPair(publicKey, privateKey);
    } catch (Exception e) {
        System.out.println(
                "====generate keypair from priv key failed, error msg:" + e.getMessage());
        return null;
    }
}
 

private ECDSASignature findSignature(BigInteger d, BigInteger e) throws Exception {
    BigInteger N = key.params.getN();
    ECPoint G = key.params.getG();
    int badrs = 0;
    BigInteger k;
    ECPoint Q;
    BigInteger r;
    BigInteger s;
    do {
        if (this.k.equals(BigInteger.ZERO) == true || badrs > 0) {
            this.deterministicK(badrs);
        }
        badrs++;
        k = this.k;
        Q = G.multiply(k);
        Q = Q.normalize();
        r = Q.getAffineXCoord().toBigInteger().mod(N);
        s = k.modInverse(N).multiply(e.add(d.multiply(r))).mod(N);
    } while (r.compareTo(BigInteger.ZERO) <= 0 || s.compareTo(BigInteger.ZERO) <= 0);

    s = toLowS(s);
    return new ECDSASignature(r, s, key.isCompressed());
}
 

public static String preimageToAddress(byte[] preimage) throws NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException {
    Security.addProvider(new BouncyCastleProvider());

    // get the hash of the preimage text
    Keccak.Digest256 digest = new Keccak.Digest256();
    digest.update(preimage);
    byte[] hash = digest.digest();

    // use the hash to derive a new address
    BigInteger keyDerivationFactor = new BigInteger(Numeric.toHexStringNoPrefix(hash), 16);
    ECPoint donatePKPoint = extractPublicKey(decodeKey(masterPubKey));
    ECPoint digestPKPoint = donatePKPoint.multiply(keyDerivationFactor);
    return getAddress(digestPKPoint);
}
 

private boolean verifyKeyPair() {
    ECNamedCurveParameterSpec curveParameters = ECNamedCurveTable.getParameterSpec(Utils.CURVE);
    ECPoint g = curveParameters.getG();
    ECPoint sG = g.multiply(((ECPrivateKey) privateKey).getS());

    return sG.equals(((ECPublicKey) publicKey).getQ());
}
 

public KeyPair generateKeyPair() {
    SM2PrivateKey privateKey = generatePrivateKey();
    ECPoint g = ecdp.getG();
    ECPoint p = g.multiply(privateKey.getD());
    SM2PublicKey publicKey = new SM2PublicKey(p);
    return new KeyPair(publicKey, privateKey);
}
 

public ECPoint initEnc(SM2 sm2, ECPoint userKey) {
    AsymmetricCipherKeyPair key = sm2.ecc_key_pair_generator.generateKeyPair();
    ECPrivateKeyParameters ecpriv = (ECPrivateKeyParameters) key.getPrivate();
    ECPublicKeyParameters ecpub = (ECPublicKeyParameters) key.getPublic();
    BigInteger k = ecpriv.getD();
    ECPoint c1 = ecpub.getQ();
    this.p2 = userKey.multiply(k);
    reset();
    return c1;
}
 

/**
 * Verify that the private key belongs to the public key.
 *
 * @param privateKey
 * @param publicKey
 * @return
 */
public static boolean verifyKeyPair(PrivateKey privateKey, PublicKey publicKey) {
    ECNamedCurveParameterSpec curveParameters = ECNamedCurveTable.getParameterSpec(CURVE);
    ECPoint g = curveParameters.getG();
    ECPoint sG = g.multiply(((java.security.interfaces.ECPrivateKey) privateKey).getS());

    return sG.equals(((ECPublicKey) publicKey).getQ());
}
 

/**
 * 公钥加密
 * 
 * @param input
 *            加密原文
 * @param publicKey
 *            公钥
 * @return
 */
public byte[] encrypt(String input, ECPoint publicKey) {
	byte[] inputBuffer = input.getBytes();
	if (debug)
		printHexString(inputBuffer);

	byte[] C1Buffer;
	ECPoint kpb;
	byte[] t;
	do {
		/* 1 产生随机数k，k属于[1, n-1] */
		BigInteger k = random(n);
		if (debug) {
			System.out.print("k: ");
			printHexString(k.toByteArray());
		}

		/* 2 计算椭圆曲线点C1 = [k]G = (x1, y1) */
		ECPoint C1 = G.multiply(k);
		C1Buffer = C1.getEncoded(false);
		if (debug) {
			System.out.print("C1: ");
			printHexString(C1Buffer);
		}

		/*
		 * 3 计算椭圆曲线点 S = [h]Pb
		 */
		BigInteger h = ecc_bc_spec.getH();
		if (h != null) {
			ECPoint S = publicKey.multiply(h);
			if (S.isInfinity())
				throw new IllegalStateException();
		}

		/* 4 计算 [k]PB = (x2, y2) */
		kpb = publicKey.multiply(k).normalize();

		/* 5 计算 t = KDF(x2||y2, klen) */
		byte[] kpbBytes = kpb.getEncoded(false);
		t = KDF(kpbBytes, inputBuffer.length);
	} while (allZero(t));

	/* 6 计算C2=M^t */
	byte[] C2 = new byte[inputBuffer.length];
	for (int i = 0; i < inputBuffer.length; i++) {
		C2[i] = (byte) (inputBuffer[i] ^ t[i]);
	}

	/* 7 计算C3 = Hash(x2 || M || y2) */
	byte[] C3 = sm3hash(kpb.getXCoord().toBigInteger().toByteArray(), inputBuffer,
			kpb.getYCoord().toBigInteger().toByteArray());

	/* 8 输出密文 C=C1 || C2 || C3 */

	byte[] encryptResult = new byte[C1Buffer.length + C2.length + C3.length];

	System.arraycopy(C1Buffer, 0, encryptResult, 0, C1Buffer.length);
	System.arraycopy(C2, 0, encryptResult, C1Buffer.length, C2.length);
	System.arraycopy(C3, 0, encryptResult, C1Buffer.length + C2.length, C3.length);

	if (debug) {
		System.out.print("密文: ");
		printHexString(encryptResult);
	}

	return encryptResult;
}
 

/**
 * 私钥解密
 * 
 * @param encryptData
 *            密文数据字节数组
 * @param privateKey
 *            解密私钥
 * @return
 */
public String decrypt(byte[] encryptData, BigInteger privateKey) {

	if (debug)
		System.out.println("encryptData length: " + encryptData.length);

	byte[] C1Byte = new byte[65];
	System.arraycopy(encryptData, 0, C1Byte, 0, C1Byte.length);

	ECPoint C1 = curve.decodePoint(C1Byte).normalize();

	/*
	 * 计算椭圆曲线点 S = [h]C1 是否为无穷点
	 */
	BigInteger h = ecc_bc_spec.getH();
	if (h != null) {
		ECPoint S = C1.multiply(h);
		if (S.isInfinity())
			throw new IllegalStateException();
	}
	/* 计算[dB]C1 = (x2, y2) */
	ECPoint dBC1 = C1.multiply(privateKey).normalize();

	/* 计算t = KDF(x2 || y2, klen) */
	byte[] dBC1Bytes = dBC1.getEncoded(false);
	int klen = encryptData.length - 65 - DIGEST_LENGTH;
	byte[] t = KDF(dBC1Bytes, klen);
	if (allZero(t)) {
		System.err.println("all zero");
		throw new IllegalStateException();
	}

	/* 5 计算M'=C2^t */
	byte[] M = new byte[klen];
	for (int i = 0; i < M.length; i++) {
		M[i] = (byte) (encryptData[C1Byte.length + i] ^ t[i]);
	}
	if (debug)
		printHexString(M);

	/* 6 计算 u = Hash(x2 || M' || y2) 判断 u == C3是否成立 */
	byte[] C3 = new byte[DIGEST_LENGTH];

	if (debug)
		try {
			System.out.println("M = " + new String(M, "UTF8"));
		} catch (UnsupportedEncodingException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}

	System.arraycopy(encryptData, encryptData.length - DIGEST_LENGTH, C3, 0, DIGEST_LENGTH);
	byte[] u = sm3hash(dBC1.getXCoord().toBigInteger().toByteArray(), M,
			dBC1.getYCoord().toBigInteger().toByteArray());
	if (Arrays.equals(u, C3)) {
		if (debug)
			System.out.println("解密成功");
		try {
			return new String(M, "UTF8");
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}
		return null;
	} else {
		if (debug) {
			System.out.print("u = ");
			printHexString(u);
			System.out.print("C3 = ");
			printHexString(C3);
			System.err.println("解密验证失败");
		}
		return null;
	}

}
 

/**
 * 公钥加密
 * 
 * @param input
 *            加密原文
 * @param publicKey
 *            公钥
 * @return
 */
public static byte[] encrypt(String input, ECPoint publicKey) {

	byte[] inputBuffer = input.getBytes();
	byte[] C1Buffer;
	ECPoint kpb;
	byte[] t;
	do {
		/* 1 产生随机数k，k属于[1, n-1] */
		BigInteger k = random(n);

		/* 2 计算椭圆曲线点C1 = [k]G = (x1, y1) */
		ECPoint C1 = G.multiply(k);
		C1Buffer = C1.getEncoded(false);

		/*
		 * 3 计算椭圆曲线点 S = [h]Pb
		 */
		BigInteger h = ecc_bc_spec.getH();
		if (h != null) {
			ECPoint S = publicKey.multiply(h);
			if (S.isInfinity())
				throw new IllegalStateException();
		}

		/* 4 计算 [k]PB = (x2, y2) */
		kpb = publicKey.multiply(k).normalize();

		/* 5 计算 t = KDF(x2||y2, klen) */
		byte[] kpbBytes = kpb.getEncoded(false);
		t = KDF(kpbBytes, inputBuffer.length);
	} while (allZero(t));

	/* 6 计算C2=M^t */
	byte[] C2 = new byte[inputBuffer.length];
	for (int i = 0; i < inputBuffer.length; i++) {
		C2[i] = (byte) (inputBuffer[i] ^ t[i]);
	}

	/* 7 计算C3 = Hash(x2 || M || y2) */
	byte[] C3 = sm3hash(kpb.getXCoord().toBigInteger().toByteArray(), inputBuffer,
			kpb.getYCoord().toBigInteger().toByteArray());

	/* 8 输出密文 C=C1 || C2 || C3 */

	byte[] encryptResult = new byte[C1Buffer.length + C2.length + C3.length];

	System.arraycopy(C1Buffer, 0, encryptResult, 0, C1Buffer.length);
	System.arraycopy(C2, 0, encryptResult, C1Buffer.length, C2.length);
	System.arraycopy(C3, 0, encryptResult, C1Buffer.length + C2.length, C3.length);

	return encryptResult;
}
 

/**
 * 私钥解密
 * 
 * @param encryptData
 *            密文数据字节数组
 * @param privateKey
 *            解密私钥
 * @return
 */
public static String decrypt(byte[] encryptData, BigInteger privateKey) {
	byte[] C1Byte = new byte[65];
	System.arraycopy(encryptData, 0, C1Byte, 0, C1Byte.length);

	ECPoint C1 = curve.decodePoint(C1Byte).normalize();

	/*
	 * 计算椭圆曲线点 S = [h]C1 是否为无穷点
	 */
	BigInteger h = ecc_bc_spec.getH();
	if (h != null) {
		ECPoint S = C1.multiply(h);
		if (S.isInfinity())
			throw new IllegalStateException();
	}
	/* 计算[dB]C1 = (x2, y2) */
	ECPoint dBC1 = C1.multiply(privateKey).normalize();

	/* 计算t = KDF(x2 || y2, klen) */
	byte[] dBC1Bytes = dBC1.getEncoded(false);
	int klen = encryptData.length - 65 - DIGEST_LENGTH;
	byte[] t = KDF(dBC1Bytes, klen);

	if (allZero(t)) {
		System.err.println("all zero");
		throw new IllegalStateException();
	}

	/* 5 计算M'=C2^t */
	byte[] M = new byte[klen];
	for (int i = 0; i < M.length; i++) {
		M[i] = (byte) (encryptData[C1Byte.length + i] ^ t[i]);
	}

	/* 6 计算 u = Hash(x2 || M' || y2) 判断 u == C3是否成立 */
	byte[] C3 = new byte[DIGEST_LENGTH];

	System.arraycopy(encryptData, encryptData.length - DIGEST_LENGTH, C3, 0, DIGEST_LENGTH);
	byte[] u = sm3hash(dBC1.getXCoord().toBigInteger().toByteArray(), M,
			dBC1.getYCoord().toBigInteger().toByteArray());
	if (Arrays.equals(u, C3)) {
		try {
			return new String(M, "UTF8");
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}
		return null;
	} else {
		return null;
	}
}
 

public void initDec(BigInteger userD, ECPoint c1) {
    this.p2 = c1.multiply(userD);
    reset();
}
 

/**
 * 公钥加密
 *
 * @param input     加密原文
 * @param publicKey 公钥
 * @return
 */
public byte[] encrypt(String input, ECPoint publicKey) {

    byte[] inputBuffer = input.getBytes();

    byte[] C1Buffer;
    ECPoint kpb;
    byte[] t;
    do {
        /* 1 产生随机数k，k属于[1, n-1] */
        BigInteger k = random(n);

        /* 2 计算椭圆曲线点C1 = [k]G = (x1, y1) */
        ECPoint C1 = G.multiply(k);
        C1Buffer = C1.getEncoded(false);

        /*
         * 3 计算椭圆曲线点 S = [h]Pb
         */
        BigInteger h = ecc_bc_spec.getH();
        if (h != null) {
            ECPoint S = publicKey.multiply(h);
            if (S.isInfinity()) {
                throw new IllegalStateException();
            }
        }

        /* 4 计算 [k]PB = (x2, y2) */
        kpb = publicKey.multiply(k).normalize();

        /* 5 计算 t = KDF(x2||y2, klen) */
        byte[] kpbBytes = kpb.getEncoded(false);
        t = KDF(kpbBytes, inputBuffer.length);
        // DerivationFunction kdf = new KDF1BytesGenerator(new
        // ShortenedDigest(new SHA256Digest(), DIGEST_LENGTH));
        //
        // t = new byte[inputBuffer.length];
        // kdf.init(new ISO18033KDFParameters(kpbBytes));
        // kdf.generateBytes(t, 0, t.length);
    } while (allZero(t));

    /* 6 计算C2=M^t */
    byte[] C2 = new byte[inputBuffer.length];
    for (int i = 0; i < inputBuffer.length; i++) {
        C2[i] = (byte) (inputBuffer[i] ^ t[i]);
    }

    /* 7 计算C3 = Hash(x2 || M || y2) */
    byte[] C3 = sm3hash(kpb.getXCoord().toBigInteger().toByteArray(), inputBuffer,
            kpb.getYCoord().toBigInteger().toByteArray());

    /* 8 输出密文 C=C1 || C2 || C3 */

    byte[] encryptResult = new byte[C1Buffer.length + C2.length + C3.length];

    System.arraycopy(C1Buffer, 0, encryptResult, 0, C1Buffer.length);
    System.arraycopy(C2, 0, encryptResult, C1Buffer.length, C2.length);
    System.arraycopy(C3, 0, encryptResult, C1Buffer.length + C2.length, C3.length);

    return encryptResult;
}
 

/**
 * 私钥解密
 *
 * @param encryptData 密文数据字节数组
 * @param privateKey  解密私钥
 * @return
 */
public String decrypt(byte[] encryptData, BigInteger privateKey) {

    byte[] C1Byte = new byte[65];
    System.arraycopy(encryptData, 0, C1Byte, 0, C1Byte.length);

    ECPoint C1 = curve.decodePoint(C1Byte).normalize();

    /*
     * 计算椭圆曲线点 S = [h]C1 是否为无穷点
     */
    BigInteger h = ecc_bc_spec.getH();
    if (h != null) {
        ECPoint S = C1.multiply(h);
        if (S.isInfinity()) {
            throw new IllegalStateException();
        }
    }
    /* 计算[dB]C1 = (x2, y2) */
    ECPoint dBC1 = C1.multiply(privateKey).normalize();

    /* 计算t = KDF(x2 || y2, klen) */
    byte[] dBC1Bytes = dBC1.getEncoded(false);
    int klen = encryptData.length - 65 - DIGEST_LENGTH;
    byte[] t = KDF(dBC1Bytes, klen);
    // DerivationFunction kdf = new KDF1BytesGenerator(new
    // ShortenedDigest(new SHA256Digest(), DIGEST_LENGTH));
    // if (debug)
    // System.out.println("klen = " + klen);
    // kdf.init(new ISO18033KDFParameters(dBC1Bytes));
    // kdf.generateBytes(t, 0, t.length);

    if (allZero(t)) {
        System.err.println("all zero");
        throw new IllegalStateException();
    }

    /* 5 计算M'=C2^t */
    byte[] M = new byte[klen];
    for (int i = 0; i < M.length; i++) {
        M[i] = (byte) (encryptData[C1Byte.length + i] ^ t[i]);
    }
    /* 6 计算 u = Hash(x2 || M' || y2) 判断 u == C3是否成立 */
    byte[] C3 = new byte[DIGEST_LENGTH];

    System.arraycopy(encryptData, encryptData.length - DIGEST_LENGTH, C3, 0, DIGEST_LENGTH);
    byte[] u = sm3hash(dBC1.getXCoord().toBigInteger().toByteArray(), M,
            dBC1.getYCoord().toBigInteger().toByteArray());
    if (Arrays.equals(u, C3)) {
        try {
            return new String(M, "UTF8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return null;
    } else {
        return null;
    }

}