Java SM2

pom

    4.0.0

    org.example
    SM2test
    1.0-SNAPSHOT

    
        
            org.bouncycastle
            bcprov-jdk15on
            1.56
        
    

Cipher 

import java.math.BigInteger;
import org.bouncycastle.crypto.AsymmetricCipherKeyPair;
import org.bouncycastle.crypto.params.ECPrivateKeyParameters;
import org.bouncycastle.crypto.params.ECPublicKeyParameters;
import org.bouncycastle.math.ec.ECPoint;

public class Cipher {
    private int ct;
    private ECPoint p2;
    private SM3Digest sm3keybase;
    private SM3Digest sm3c3;
    private byte key[];
    private byte keyOff;

    public Cipher()
    {
        this.ct = 1;
        this.key = new byte[32];
        this.keyOff = 0;
    }

    private void Reset()
    {
        this.sm3keybase = new SM3Digest();
        this.sm3c3 = new SM3Digest();

        byte p[] = Util.byteConvert32Bytes(p2.getX().toBigInteger());
        this.sm3keybase.update(p, 0, p.length);
        this.sm3c3.update(p, 0, p.length);

        p = Util.byteConvert32Bytes(p2.getY().toBigInteger());
        this.sm3keybase.update(p, 0, p.length);
        this.ct = 1;
        NextKey();
    }

    private void NextKey()
    {
        SM3Digest sm3keycur = new SM3Digest(this.sm3keybase);
        sm3keycur.update((byte) (ct >> 24 & 0xff));
        sm3keycur.update((byte) (ct >> 16 & 0xff));
        sm3keycur.update((byte) (ct >> 8 & 0xff));
        sm3keycur.update((byte) (ct & 0xff));
        sm3keycur.doFinal(key, 0);
        this.keyOff = 0;
        this.ct++;
    }

    public ECPoint Init_enc(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;
    }

    public void Encrypt(byte data[])
    {
        this.sm3c3.update(data, 0, data.length);
        for (int i = 0; i < data.length; i++)
        {
            if (keyOff == key.length)
            {
                NextKey();
            }
            data[i] ^= key[keyOff++];
        }
    }

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

    public void Decrypt(byte data[])
    {
        for (int i = 0; i < data.length; i++)
        {
            if (keyOff == key.length)
            {
                NextKey();
            }
            data[i] ^= key[keyOff++];
        }

        this.sm3c3.update(data, 0, data.length);
    }

    public void Dofinal(byte c3[])
    {
        byte p[] = Util.byteConvert32Bytes(p2.getY().toBigInteger());
        this.sm3c3.update(p, 0, p.length);
        this.sm3c3.doFinal(c3, 0);
        Reset();
    }
}

SM2

import java.math.BigInteger;
import java.security.SecureRandom;

import org.bouncycastle.crypto.generators.ECKeyPairGenerator;
import org.bouncycastle.crypto.params.ECDomainParameters;
import org.bouncycastle.crypto.params.ECKeyGenerationParameters;
import org.bouncycastle.math.ec.ECCurve;
import org.bouncycastle.math.ec.ECFieldElement;
import org.bouncycastle.math.ec.ECPoint;
import org.bouncycastle.math.ec.ECFieldElement.Fp;

public class SM2 {

    //正式参数
    public static String[] ecc_param = {
            "FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFF",
            "FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFC",
            "28E9FA9E9D9F5E344D5A9E4BCF6509A7F39789F515AB8F92DDBCBD414D940E93",
            "FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFF7203DF6B21C6052B53BBF40939D54123",
            "32C4AE2C1F1981195F9904466A39C9948FE30BBFF2660BE1715A4589334C74C7",
            "BC3736A2F4F6779C59BDCEE36B692153D0A9877CC62A474002DF32E52139F0A0"
    };

    public static SM2 Instance() {
        return new SM2();
    }

    public final BigInteger ecc_p;
    public final BigInteger ecc_a;
    public final BigInteger ecc_b;
    public final BigInteger ecc_n;
    public final BigInteger ecc_gx;
    public final BigInteger ecc_gy;
    public final ECCurve ecc_curve;
    public final ECPoint ecc_point_g;
    public final ECDomainParameters ecc_bc_spec;
    public final ECKeyPairGenerator ecc_key_pair_generator;
    public final ECFieldElement ecc_gx_fieldelement;
    public final ECFieldElement ecc_gy_fieldelement;

    public SM2() {
        this.ecc_p = new BigInteger(ecc_param[0], 16);
        this.ecc_a = new BigInteger(ecc_param[1], 16);
        this.ecc_b = new BigInteger(ecc_param[2], 16);
        this.ecc_n = new BigInteger(ecc_param[3], 16);
        this.ecc_gx = new BigInteger(ecc_param[4], 16);
        this.ecc_gy = new BigInteger(ecc_param[5], 16);

        this.ecc_gx_fieldelement = new Fp(this.ecc_p, this.ecc_gx);
        this.ecc_gy_fieldelement = new Fp(this.ecc_p, this.ecc_gy);

        this.ecc_curve = new ECCurve.Fp(this.ecc_p, this.ecc_a, this.ecc_b);
        this.ecc_point_g = new ECPoint.Fp(this.ecc_curve, this.ecc_gx_fieldelement, this.ecc_gy_fieldelement);

        this.ecc_bc_spec = new ECDomainParameters(this.ecc_curve, this.ecc_point_g, this.ecc_n);

        ECKeyGenerationParameters ecc_ecgenparam;
        ecc_ecgenparam = new ECKeyGenerationParameters(this.ecc_bc_spec, new SecureRandom());

        this.ecc_key_pair_generator = new ECKeyPairGenerator();
        this.ecc_key_pair_generator.init(ecc_ecgenparam);
    }
}

SM2KeyPair

public class SM2KeyPair {

    /** 公钥 */
    private  String publicKey;

    /** 私钥 */
    private String privateKey;

    SM2KeyPair(String publicKey, String privateKey) {
        this.publicKey = publicKey;
        this.privateKey = privateKey;
    }

    public String getPublicKey() {
        return publicKey;
    }

    public String getPrivateKey() {
        return privateKey;
    }

}

SM2Utils

import java.io.IOException;
import java.math.BigInteger;
import org.bouncycastle.crypto.AsymmetricCipherKeyPair;
import org.bouncycastle.crypto.params.ECPrivateKeyParameters;
import org.bouncycastle.crypto.params.ECPublicKeyParameters;
import org.bouncycastle.math.ec.ECPoint;

public class SM2Utils {
    //生成随机秘钥对
    public static SM2KeyPair generateKeyPair() {
        SM2 sm2 = SM2.Instance();
        AsymmetricCipherKeyPair key = sm2.ecc_key_pair_generator.generateKeyPair();
        ECPrivateKeyParameters ecpriv = (ECPrivateKeyParameters) key.getPrivate();
        ECPublicKeyParameters ecpub = (ECPublicKeyParameters) key.getPublic();
        BigInteger privateKey = ecpriv.getD();
        ECPoint publicKey = ecpub.getQ();
        System.out.println("公钥: " + Util.byteToHex(publicKey.getEncoded()));
        System.out.println("私钥: " + Util.byteToHex(privateKey.toByteArray()));
        return new SM2KeyPair(Util.byteToHex(publicKey.getEncoded(false)), Util.byteToHex(privateKey.toByteArray()));
    }


    //数据加密
    public static String encrypt(byte[] publicKey, byte[] data) throws IOException {
        if (publicKey == null || publicKey.length == 0) {
            return null;
        }

        if (data == null || data.length == 0) {
            return null;
        }

        byte[] source = new byte[data.length];
        System.arraycopy(data, 0, source, 0, data.length);

        Cipher cipher = new Cipher();
        SM2 sm2 = SM2.Instance();
        ECPoint userKey = sm2.ecc_curve.decodePoint(publicKey);

        ECPoint c1 = cipher.Init_enc(sm2, userKey);
        cipher.Encrypt(source);
        byte[] c3 = new byte[32];
        cipher.Dofinal(c3);

//      System.out.println("C1 " + Util.byteToHex(c1.getEncoded()));
//      System.out.println("C2 " + Util.byteToHex(source));
//      System.out.println("C3 " + Util.byteToHex(c3));
        //C1 C2 C3拼装成加密字串
        return Util.byteToHex(c1.getEncoded(false)) + Util.byteToHex(source) + Util.byteToHex(c3);

    }

    //数据解密
    public static byte[] decrypt(byte[] privateKey, byte[] encryptedData) throws IOException {
        if (privateKey == null || privateKey.length == 0) {
            return null;
        }

        if (encryptedData == null || encryptedData.length == 0) {
            return null;
        }
        //加密字节数组转换为十六进制的字符串 长度变为encryptedData.length * 2
        String data = Util.byteToHex(encryptedData);
        /***分解加密字串
         * （C1 = C1标志位2位 + C1实体部分128位 = 130）
         * （C3 = C3实体部分64位  = 64）
         * （C2 = encryptedData.length * 2 - C1长度  - C2长度）
         */
        byte[] c1Bytes = Util.hexToByte(data.substring(0, 130));
        int c2Len = encryptedData.length - 97;
        byte[] c2 = Util.hexToByte(data.substring(130, 130 + 2 * c2Len));
        byte[] c3 = Util.hexToByte(data.substring(130 + 2 * c2Len, 194 + 2 * c2Len));

        SM2 sm2 = SM2.Instance();
        BigInteger userD = new BigInteger(1, privateKey);

        //通过C1实体字节来生成ECPoint
        ECPoint c1 = sm2.ecc_curve.decodePoint(c1Bytes);
        Cipher cipher = new Cipher();
        cipher.Init_dec(userD, c1);
        cipher.Decrypt(c2);
        cipher.Dofinal(c3);

        //返回解密结果
        return c2;
    }


    public static void main(String[] args) throws Exception {
        //生成密钥对
        generateKeyPair();
        String plainText = "lxw测试！@#￥%……&*（）";
        //下面的秘钥可以使用generateKeyPair()生成的秘钥内容
        // 国密规范正式私钥
        String prik = "7BF3DC32F3CCA2176CD8EA9267EE06E02E51378E7EA52CCEB42346BE70186804";
        // 国密规范正式公钥
        String pubk = "0497077E61FA0168D4EB00F475CAA21629D8BE5377311EAB2BB59D98B00970D0B9571935D8D4DB4DB8C24923FEBC3951088805EBF7989F16694CE57A903D24317B";
        System.out.println("-------加密: ");
        String cipherText = SM2Utils.encrypt(Util.hexStringToBytes(pubk), plainText.getBytes());
        System.out.println(cipherText);
        System.out.println("-------加密后字符串长度:" + cipherText.length());
        System.out.println("-------解密: ");
        byte[] decrypt = SM2Utils.decrypt(Util.hexStringToBytes(prik), Util.hexStringToBytes(cipherText));
        System.out.println(new String(decrypt));
    }

}

SM3 

public class SM3 {
    public static final byte[] iv = { 0x73, (byte) 0x80, 0x16, 0x6f, 0x49,
            0x14, (byte) 0xb2, (byte) 0xb9, 0x17, 0x24, 0x42, (byte) 0xd7,
            (byte) 0xda, (byte) 0x8a, 0x06, 0x00, (byte) 0xa9, 0x6f, 0x30,
            (byte) 0xbc, (byte) 0x16, 0x31, 0x38, (byte) 0xaa, (byte) 0xe3,
            (byte) 0x8d, (byte) 0xee, 0x4d, (byte) 0xb0, (byte) 0xfb, 0x0e,
            0x4e };

    public static int[] Tj = new int[64];

    static
    {
        for (int i = 0; i < 16; i++)
        {
            Tj[i] = 0x79cc4519;
        }

        for (int i = 16; i < 64; i++)
        {
            Tj[i] = 0x7a879d8a;
        }
    }

    public static byte[] CF(byte[] V, byte[] B)
    {
        int[] v, b;
        v = convert(V);
        b = convert(B);
        return convert(CF(v, b));
    }

    private static int[] convert(byte[] arr)
    {
        int[] out = new int[arr.length / 4];
        byte[] tmp = new byte[4];
        for (int i = 0; i < arr.length; i += 4)
        {
            System.arraycopy(arr, i, tmp, 0, 4);
            out[i / 4] = bigEndianByteToInt(tmp);
        }
        return out;
    }

    private static byte[] convert(int[] arr)
    {
        byte[] out = new byte[arr.length * 4];
        byte[] tmp = null;
        for (int i = 0; i < arr.length; i++)
        {
            tmp = bigEndianIntToByte(arr[i]);
            System.arraycopy(tmp, 0, out, i * 4, 4);
        }
        return out;
    }

    public static int[] CF(int[] V, int[] B)
    {
        int a, b, c, d, e, f, g, h;
        int ss1, ss2, tt1, tt2;
        a = V[0];
        b = V[1];
        c = V[2];
        d = V[3];
        e = V[4];
        f = V[5];
        g = V[6];
        h = V[7];

        int[][] arr = expand(B);
        int[] w = arr[0];
        int[] w1 = arr[1];

        for (int j = 0; j < 64; j++)
        {
            ss1 = (bitCycleLeft(a, 12) + e + bitCycleLeft(Tj[j], j));
            ss1 = bitCycleLeft(ss1, 7);
            ss2 = ss1 ^ bitCycleLeft(a, 12);
            tt1 = FFj(a, b, c, j) + d + ss2 + w1[j];
            tt2 = GGj(e, f, g, j) + h + ss1 + w[j];
            d = c;
            c = bitCycleLeft(b, 9);
            b = a;
            a = tt1;
            h = g;
            g = bitCycleLeft(f, 19);
            f = e;
            e = P0(tt2);

		            /*System.out.print(j+" ");
		            System.out.print(Integer.toHexString(a)+" ");
		            System.out.print(Integer.toHexString(b)+" ");
		            System.out.print(Integer.toHexString(c)+" ");
		            System.out.print(Integer.toHexString(d)+" ");
		            System.out.print(Integer.toHexString(e)+" ");
		            System.out.print(Integer.toHexString(f)+" ");
		            System.out.print(Integer.toHexString(g)+" ");
		            System.out.print(Integer.toHexString(h)+" ");
		            System.out.println("");*/
        }
//		      System.out.println("");

        int[] out = new int[8];
        out[0] = a ^ V[0];
        out[1] = b ^ V[1];
        out[2] = c ^ V[2];
        out[3] = d ^ V[3];
        out[4] = e ^ V[4];
        out[5] = f ^ V[5];
        out[6] = g ^ V[6];
        out[7] = h ^ V[7];

        return out;
    }

    private static int[][] expand(int[] B)
    {
        int W[] = new int[68];
        int W1[] = new int[64];
        for (int i = 0; i < B.length; i++)
        {
            W[i] = B[i];
        }

        for (int i = 16; i < 68; i++)
        {
            W[i] = P1(W[i - 16] ^ W[i - 9] ^ bitCycleLeft(W[i - 3], 15))
                    ^ bitCycleLeft(W[i - 13], 7) ^ W[i - 6];
        }

        for (int i = 0; i < 64; i++)
        {
            W1[i] = W[i] ^ W[i + 4];
        }

        int arr[][] = new int[][] { W, W1 };
        return arr;
    }

    private static byte[] bigEndianIntToByte(int num)
    {
        return back(Util.intToBytes(num));
    }

    private static int bigEndianByteToInt(byte[] bytes)
    {
        return Util.byteToInt(back(bytes));
    }

    private static int FFj(int X, int Y, int Z, int j)
    {
        if (j >= 0 && j <= 15)
        {
            return FF1j(X, Y, Z);
        }
        else
        {
            return FF2j(X, Y, Z);
        }
    }

    private static int GGj(int X, int Y, int Z, int j)
    {
        if (j >= 0 && j <= 15)
        {
            return GG1j(X, Y, Z);
        }
        else
        {
            return GG2j(X, Y, Z);
        }
    }

    // 逻辑位运算函数
    private static int FF1j(int X, int Y, int Z)
    {
        int tmp = X ^ Y ^ Z;
        return tmp;
    }

    private static int FF2j(int X, int Y, int Z)
    {
        int tmp = ((X & Y) | (X & Z) | (Y & Z));
        return tmp;
    }

    private static int GG1j(int X, int Y, int Z)
    {
        int tmp = X ^ Y ^ Z;
        return tmp;
    }

    private static int GG2j(int X, int Y, int Z)
    {
        int tmp = (X & Y) | (~X & Z);
        return tmp;
    }

    private static int P0(int X)
    {
        int y = rotateLeft(X, 9);
        y = bitCycleLeft(X, 9);
        int z = rotateLeft(X, 17);
        z = bitCycleLeft(X, 17);
        int t = X ^ y ^ z;
        return t;
    }

    private static int P1(int X)
    {
        int t = X ^ bitCycleLeft(X, 15) ^ bitCycleLeft(X, 23);
        return t;
    }

    /**
     * 对最后一个分组字节数据padding
     *
     * @param in
     * @param bLen
     *            分组个数
     * @return
     */
    public static byte[] padding(byte[] in, int bLen)
    {
        int k = 448 - (8 * in.length + 1) % 512;
        if (k < 0)
        {
            k = 960 - (8 * in.length + 1) % 512;
        }
        k += 1;
        byte[] padd = new byte[k / 8];
        padd[0] = (byte) 0x80;
        long n = in.length * 8 + bLen * 512;
        byte[] out = new byte[in.length + k / 8 + 64 / 8];
        int pos = 0;
        System.arraycopy(in, 0, out, 0, in.length);
        pos += in.length;
        System.arraycopy(padd, 0, out, pos, padd.length);
        pos += padd.length;
        byte[] tmp = back(Util.longToBytes(n));
        System.arraycopy(tmp, 0, out, pos, tmp.length);
        return out;
    }

    /**
     * 字节数组逆序
     *
     * @param in
     * @return
     */
    private static byte[] back(byte[] in)
    {
        byte[] out = new byte[in.length];
        for (int i = 0; i < out.length; i++)
        {
            out[i] = in[out.length - i - 1];
        }

        return out;
    }

    public static int rotateLeft(int x, int n)
    {
        return (x << n) | (x >> (32 - n));
    }

    private static int bitCycleLeft(int n, int bitLen)
    {
        bitLen %= 32;
        byte[] tmp = bigEndianIntToByte(n);
        int byteLen = bitLen / 8;
        int len = bitLen % 8;
        if (byteLen > 0)
        {
            tmp = byteCycleLeft(tmp, byteLen);
        }

        if (len > 0)
        {
            tmp = bitSmall8CycleLeft(tmp, len);
        }

        return bigEndianByteToInt(tmp);
    }

    private static byte[] bitSmall8CycleLeft(byte[] in, int len)
    {
        byte[] tmp = new byte[in.length];
        int t1, t2, t3;
        for (int i = 0; i < tmp.length; i++)
        {
            t1 = (byte) ((in[i] & 0x000000ff) << len);
            t2 = (byte) ((in[(i + 1) % tmp.length] & 0x000000ff) >> (8 - len));
            t3 = (byte) (t1 | t2);
            tmp[i] = (byte) t3;
        }

        return tmp;
    }

    private static byte[] byteCycleLeft(byte[] in, int byteLen)
    {
        byte[] tmp = new byte[in.length];
        System.arraycopy(in, byteLen, tmp, 0, in.length - byteLen);
        System.arraycopy(in, 0, tmp, in.length - byteLen, byteLen);
        return tmp;
    }
}

SM3Digest

import org.bouncycastle.util.encoders.Hex;

public class SM3Digest {
    /** SM3值的长度 */
    private static final int BYTE_LENGTH = 32;

    /** SM3分组长度 */
    private static final int BLOCK_LENGTH = 64;

    /** 缓冲区长度 */
    private static final int BUFFER_LENGTH = BLOCK_LENGTH * 1;

    /** 缓冲区 */
    private byte[] xBuf = new byte[BUFFER_LENGTH];

    /** 缓冲区偏移量 */
    private int xBufOff;

    /** 初始向量 */
    private byte[] V = SM3.iv.clone();

    private int cntBlock = 0;

    public SM3Digest() {
    }

    public SM3Digest(SM3Digest t)
    {
        System.arraycopy(t.xBuf, 0, this.xBuf, 0, t.xBuf.length);
        this.xBufOff = t.xBufOff;
        System.arraycopy(t.V, 0, this.V, 0, t.V.length);
    }

    /**
     * SM3结果输出
     *
     * @param out 保存SM3结构的缓冲区
     * @param outOff 缓冲区偏移量
     * @return
     */
    public int doFinal(byte[] out, int outOff)
    {
        byte[] tmp = doFinal();
        System.arraycopy(tmp, 0, out, 0, tmp.length);
        return BYTE_LENGTH;
    }

    public void reset()
    {
        xBufOff = 0;
        cntBlock = 0;
        V = SM3.iv.clone();
    }

    /**
     * 明文输入
     *
     * @param in
     *            明文输入缓冲区
     * @param inOff
     *            缓冲区偏移量
     * @param len
     *            明文长度
     */
    public void update(byte[] in, int inOff, int len)
    {
        int partLen = BUFFER_LENGTH - xBufOff;
        int inputLen = len;
        int dPos = inOff;
        if (partLen < inputLen)
        {
            System.arraycopy(in, dPos, xBuf, xBufOff, partLen);
            inputLen -= partLen;
            dPos += partLen;
            doUpdate();
            while (inputLen > BUFFER_LENGTH)
            {
                System.arraycopy(in, dPos, xBuf, 0, BUFFER_LENGTH);
                inputLen -= BUFFER_LENGTH;
                dPos += BUFFER_LENGTH;
                doUpdate();
            }
        }

        System.arraycopy(in, dPos, xBuf, xBufOff, inputLen);
        xBufOff += inputLen;
    }

    private void doUpdate()
    {
        byte[] B = new byte[BLOCK_LENGTH];
        for (int i = 0; i < BUFFER_LENGTH; i += BLOCK_LENGTH)
        {
            System.arraycopy(xBuf, i, B, 0, B.length);
            doHash(B);
        }
        xBufOff = 0;
    }

    private void doHash(byte[] B)
    {
        byte[] tmp = SM3.CF(V, B);
        System.arraycopy(tmp, 0, V, 0, V.length);
        cntBlock++;
    }

    private byte[] doFinal()
    {
        byte[] B = new byte[BLOCK_LENGTH];
        byte[] buffer = new byte[xBufOff];
        System.arraycopy(xBuf, 0, buffer, 0, buffer.length);
        byte[] tmp = SM3.padding(buffer, cntBlock);
        for (int i = 0; i < tmp.length; i += BLOCK_LENGTH)
        {
            System.arraycopy(tmp, i, B, 0, B.length);
            doHash(B);
        }
        return V;
    }

    public void update(byte in)
    {
        byte[] buffer = new byte[] { in };
        update(buffer, 0, 1);
    }

    public int getDigestSize()
    {
        return BYTE_LENGTH;
    }

    public static void main(String[] args)
    {
        byte[] md = new byte[32];
        byte[] msg1 = "lxw 测试".getBytes();
        SM3Digest sm3 = new SM3Digest();
        sm3.update(msg1, 0, msg1.length);
        sm3.doFinal(md, 0);
        String s = new String(Hex.encode(md));
        System.out.println(s.toUpperCase());
    }
}

Util

import java.math.BigInteger;

public class Util {
    /**
     * 整形转换成网络传输的字节流（字节数组）型数据
     *
     * @param num 一个整型数据
     * @return 4个字节的自己数组
     */
    public static byte[] intToBytes(int num)
    {
        byte[] bytes = new byte[4];
        bytes[0] = (byte) (0xff & (num >> 0));
        bytes[1] = (byte) (0xff & (num >> 8));
        bytes[2] = (byte) (0xff & (num >> 16));
        bytes[3] = (byte) (0xff & (num >> 24));
        return bytes;
    }

    /**
     * 四个字节的字节数据转换成一个整形数据
     *
     * @param bytes 4个字节的字节数组
     * @return 一个整型数据
     */
    public static int byteToInt(byte[] bytes)
    {
        int num = 0;
        int temp;
        temp = (0x000000ff & (bytes[0])) << 0;
        num = num | temp;
        temp = (0x000000ff & (bytes[1])) << 8;
        num = num | temp;
        temp = (0x000000ff & (bytes[2])) << 16;
        num = num | temp;
        temp = (0x000000ff & (bytes[3])) << 24;
        num = num | temp;
        return num;
    }

    /**
     * 长整形转换成网络传输的字节流（字节数组）型数据
     *
     * @param num 一个长整型数据
     * @return 4个字节的自己数组
     */
    public static byte[] longToBytes(long num)
    {
        byte[] bytes = new byte[8];
        for (int i = 0; i < 8; i++)
        {
            bytes[i] = (byte) (0xff & (num >> (i * 8)));
        }

        return bytes;
    }

    /**
     * 大数字转换字节流（字节数组）型数据
     *
     * @param n
     * @return
     */
    public static byte[] byteConvert32Bytes(BigInteger n)
    {
        byte tmpd[] = (byte[])null;
        if(n == null)
        {
            return null;
        }

        if(n.toByteArray().length == 33)
        {
            tmpd = new byte[32];
            System.arraycopy(n.toByteArray(), 1, tmpd, 0, 32);
        }
        else if(n.toByteArray().length == 32)
        {
            tmpd = n.toByteArray();
        }
        else
        {
            tmpd = new byte[32];
            for(int i = 0; i < 32 - n.toByteArray().length; i++)
            {
                tmpd[i] = 0;
            }
            System.arraycopy(n.toByteArray(), 0, tmpd, 32 - n.toByteArray().length, n.toByteArray().length);
        }
        return tmpd;
    }

    /**
     * 换字节流（字节数组）型数据转大数字
     *
     * @param b
     * @return
     */
    public static BigInteger byteConvertInteger(byte[] b)
    {
        if (b[0] < 0)
        {
            byte[] temp = new byte[b.length + 1];
            temp[0] = 0;
            System.arraycopy(b, 0, temp, 1, b.length);
            return new BigInteger(temp);
        }
        return new BigInteger(b);
    }

    /**
     * 根据字节数组获得值(十六进制数字)
     *
     * @param bytes
     * @return
     */
    public static String getHexString(byte[] bytes)
    {
        return getHexString(bytes, true);
    }

    /**
     * 根据字节数组获得值(十六进制数字)
     *
     * @param bytes
     * @param upperCase
     * @return
     */
    public static String getHexString(byte[] bytes, boolean upperCase)
    {
        String ret = "";
        for (int i = 0; i < bytes.length; i++)
        {
            ret += Integer.toString((bytes[i] & 0xff) + 0x100, 16).substring(1);
        }
        return upperCase ? ret.toUpperCase() : ret;
    }

    /**
     * 打印十六进制字符串
     *
     * @param bytes
     */
    public static void printHexString(byte[] bytes)
    {
        for (int i = 0; i < bytes.length; i++)
        {
            String hex = Integer.toHexString(bytes[i] & 0xFF);
            if (hex.length() == 1)
            {
                hex = '0' + hex;
            }
            System.out.print("0x" + hex.toUpperCase() + ",");
        }
        System.out.println("");
    }

    /**
     * Convert hex string to byte[]
     *
     * @param hexString
     *            the hex string
     * @return byte[]
     */
    public static byte[] hexStringToBytes(String hexString)
    {
        if (hexString == null || hexString.equals(""))
        {
            return null;
        }

        hexString = hexString.toUpperCase();
        int length = hexString.length() / 2;
        char[] hexChars = hexString.toCharArray();
        byte[] d = new byte[length];
        for (int i = 0; i < length; i++)
        {
            int pos = i * 2;
            d[i] = (byte) (charToByte(hexChars[pos]) << 4 | charToByte(hexChars[pos + 1]));
        }
        return d;
    }

    /**
     * Convert char to byte
     *
     * @param c
     *            char
     * @return byte
     */
    public static byte charToByte(char c)
    {
        return (byte) "0123456789ABCDEF".indexOf(c);
    }

    /**
     * 用于建立十六进制字符的输出的小写字符数组
     */
    private static final char[] DIGITS_LOWER = {'0', '1', '2', '3', '4', '5',
            '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};

    /**
     * 用于建立十六进制字符的输出的大写字符数组
     */
    private static final char[] DIGITS_UPPER = {'0', '1', '2', '3', '4', '5',
            '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};

    /**
     * 将字节数组转换为十六进制字符数组
     *
     * @param data byte[]
     * @return 十六进制char[]
     */
    public static char[] encodeHex(byte[] data) {
        return encodeHex(data, true);
    }

    /**
     * 将字节数组转换为十六进制字符数组
     *
     * @param data        byte[]
     * @param toLowerCase true 传换成小写格式 ， false 传换成大写格式
     * @return 十六进制char[]
     */
    public static char[] encodeHex(byte[] data, boolean toLowerCase) {
        return encodeHex(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER);
    }

    /**
     * 将字节数组转换为十六进制字符数组
     *
     * @param data     byte[]
     * @param toDigits 用于控制输出的char[]
     * @return 十六进制char[]
     */
    protected static char[] encodeHex(byte[] data, char[] toDigits) {
        int l = data.length;
        char[] out = new char[l << 1];
        // two characters form the hex value.
        for (int i = 0, j = 0; i < l; i++) {
            out[j++] = toDigits[(0xF0 & data[i]) >>> 4];
            out[j++] = toDigits[0x0F & data[i]];
        }
        return out;
    }

    /**
     * 将字节数组转换为十六进制字符串
     *
     * @param data byte[]
     * @return 十六进制String
     */
    public static String encodeHexString(byte[] data) {
        return encodeHexString(data, true);
    }

    /**
     * 将字节数组转换为十六进制字符串
     *
     * @param data        byte[]
     * @param toLowerCase true 传换成小写格式 ， false 传换成大写格式
     * @return 十六进制String
     */
    public static String encodeHexString(byte[] data, boolean toLowerCase) {
        return encodeHexString(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER);
    }

    /**
     * 将字节数组转换为十六进制字符串
     *
     * @param data     byte[]
     * @param toDigits 用于控制输出的char[]
     * @return 十六进制String
     */
    protected static String encodeHexString(byte[] data, char[] toDigits) {
        return new String(encodeHex(data, toDigits));
    }

    /**
     * 将十六进制字符数组转换为字节数组
     *
     * @param data 十六进制char[]
     * @return byte[]
     * @throws RuntimeException 如果源十六进制字符数组是一个奇怪的长度，将抛出运行时异常
     */
    public static byte[] decodeHex(char[] data) {
        int len = data.length;

        if ((len & 0x01) != 0) {
            throw new RuntimeException("Odd number of characters.");
        }

        byte[] out = new byte[len >> 1];

        // two characters form the hex value.
        for (int i = 0, j = 0; j < len; i++) {
            int f = toDigit(data[j], j) << 4;
            j++;
            f = f | toDigit(data[j], j);
            j++;
            out[i] = (byte) (f & 0xFF);
        }

        return out;
    }

    /**
     * 将十六进制字符转换成一个整数
     *
     * @param ch    十六进制char
     * @param index 十六进制字符在字符数组中的位置
     * @return 一个整数
     * @throws RuntimeException 当ch不是一个合法的十六进制字符时，抛出运行时异常
     */
    protected static int toDigit(char ch, int index) {
        int digit = Character.digit(ch, 16);
        if (digit == -1) {
            throw new RuntimeException("Illegal hexadecimal character " + ch
                    + " at index " + index);
        }
        return digit;
    }

    /**
     * 数字字符串转ASCII码字符串
     *
     * @param content
     *            字符串
     * @return ASCII字符串
     */
    public static String StringToAsciiString(String content) {
        String result = "";
        int max = content.length();
        for (int i = 0; i < max; i++) {
            char c = content.charAt(i);
            String b = Integer.toHexString(c);
            result = result + b;
        }
        return result;
    }

    /**
     * 十六进制转字符串
     *
     * @param hexString
     *            十六进制字符串
     * @param encodeType
     *            编码类型4：Unicode，2：普通编码
     * @return 字符串
     */
    public static String hexStringToString(String hexString, int encodeType) {
        String result = "";
        int max = hexString.length() / encodeType;
        for (int i = 0; i < max; i++) {
            char c = (char) hexStringToAlgorism(hexString
                    .substring(i * encodeType, (i + 1) * encodeType));
            result += c;
        }
        return result;
    }

    /**
     * 十六进制字符串装十进制
     *
     * @param hex
     *            十六进制字符串
     * @return 十进制数值
     */
    public static int hexStringToAlgorism(String hex) {
        hex = hex.toUpperCase();
        int max = hex.length();
        int result = 0;
        for (int i = max; i > 0; i--) {
            char c = hex.charAt(i - 1);
            int algorism = 0;
            if (c >= '0' && c <= '9') {
                algorism = c - '0';
            } else {
                algorism = c - 55;
            }
            result += Math.pow(16, max - i) * algorism;
        }
        return result;
    }

    /**
     * 十六转二进制
     *
     * @param hex
     *            十六进制字符串
     * @return 二进制字符串
     */
    public static String hexStringToBinary(String hex) {
        hex = hex.toUpperCase();
        String result = "";
        int max = hex.length();
        for (int i = 0; i < max; i++) {
            char c = hex.charAt(i);
            switch (c) {
                case '0':
                    result += "0000";
                    break;
                case '1':
                    result += "0001";
                    break;
                case '2':
                    result += "0010";
                    break;
                case '3':
                    result += "0011";
                    break;
                case '4':
                    result += "0100";
                    break;
                case '5':
                    result += "0101";
                    break;
                case '6':
                    result += "0110";
                    break;
                case '7':
                    result += "0111";
                    break;
                case '8':
                    result += "1000";
                    break;
                case '9':
                    result += "1001";
                    break;
                case 'A':
                    result += "1010";
                    break;
                case 'B':
                    result += "1011";
                    break;
                case 'C':
                    result += "1100";
                    break;
                case 'D':
                    result += "1101";
                    break;
                case 'E':
                    result += "1110";
                    break;
                case 'F':
                    result += "1111";
                    break;
            }
        }
        return result;
    }

    /**
     * ASCII码字符串转数字字符串
     *
     * @param content
     *            ASCII字符串
     * @return 字符串
     */
    public static String AsciiStringToString(String content) {
        String result = "";
        int length = content.length() / 2;
        for (int i = 0; i < length; i++) {
            String c = content.substring(i * 2, i * 2 + 2);
            int a = hexStringToAlgorism(c);
            char b = (char) a;
            String d = String.valueOf(b);
            result += d;
        }
        return result;
    }

    /**
     * 将十进制转换为指定长度的十六进制字符串
     *
     * @param algorism
     *            int 十进制数字
     * @param maxLength
     *            int 转换后的十六进制字符串长度
     * @return String 转换后的十六进制字符串
     */
    public static String algorismToHexString(int algorism, int maxLength) {
        String result = "";
        result = Integer.toHexString(algorism);

        if (result.length() % 2 == 1) {
            result = "0" + result;
        }
        return patchHexString(result.toUpperCase(), maxLength);
    }

    /**
     * 字节数组转为普通字符串（ASCII对应的字符）
     *
     * @param bytearray
     *            byte[]
     * @return String
     */
    public static String byteToString(byte[] bytearray) {
        String result = "";
        char temp;

        int length = bytearray.length;
        for (int i = 0; i < length; i++) {
            temp = (char) bytearray[i];
            result += temp;
        }
        return result;
    }

    /**
     * 二进制字符串转十进制
     *
     * @param binary
     *            二进制字符串
     * @return 十进制数值
     */
    public static int binaryToAlgorism(String binary) {
        int max = binary.length();
        int result = 0;
        for (int i = max; i > 0; i--) {
            char c = binary.charAt(i - 1);
            int algorism = c - '0';
            result += Math.pow(2, max - i) * algorism;
        }
        return result;
    }

    /**
     * 十进制转换为十六进制字符串
     *
     * @param algorism
     *            int 十进制的数字
     * @return String 对应的十六进制字符串
     */
    public static String algorismToHEXString(int algorism) {
        String result = "";
        result = Integer.toHexString(algorism);

        if (result.length() % 2 == 1) {
            result = "0" + result;

        }
        result = result.toUpperCase();

        return result;
    }

    /**
     * HEX字符串前补0，主要用于长度位数不足。
     *
     * @param str
     *            String 需要补充长度的十六进制字符串
     * @param maxLength
     *            int 补充后十六进制字符串的长度
     * @return 补充结果
     */
    static public String patchHexString(String str, int maxLength) {
        String temp = "";
        for (int i = 0; i < maxLength - str.length(); i++) {
            temp = "0" + temp;
        }
        str = (temp + str).substring(0, maxLength);
        return str;
    }

    /**
     * 将一个字符串转换为int
     *
     * @param s
     *            String 要转换的字符串
     * @param defaultInt
     *            int 如果出现异常,默认返回的数字
     * @param radix
     *            int 要转换的字符串是什么进制的,如16 8 10.
     * @return int 转换后的数字
     */
    public static int parseToInt(String s, int defaultInt, int radix) {
        int i = 0;
        try {
            i = Integer.parseInt(s, radix);
        } catch (NumberFormatException ex) {
            i = defaultInt;
        }
        return i;
    }

    /**
     * 将一个十进制形式的数字字符串转换为int
     *
     * @param s
     *            String 要转换的字符串
     * @param defaultInt
     *            int 如果出现异常,默认返回的数字
     * @return int 转换后的数字
     */
    public static int parseToInt(String s, int defaultInt) {
        int i = 0;
        try {
            i = Integer.parseInt(s);
        } catch (NumberFormatException ex) {
            i = defaultInt;
        }
        return i;
    }

    /**
     * 十六进制串转化为byte数组
     *
     * @return the array of byte
     */
    public static byte[] hexToByte(String hex)
            throws IllegalArgumentException {
        if (hex.length() % 2 != 0) {
            throw new IllegalArgumentException();
        }
        char[] arr = hex.toCharArray();
        byte[] b = new byte[hex.length() / 2];
        for (int i = 0, j = 0, l = hex.length(); i < l; i++, j++) {
            String swap = "" + arr[i++] + arr[i];
            int byteint = Integer.parseInt(swap, 16) & 0xFF;
            b[j] = new Integer(byteint).byteValue();
        }
        return b;
    }

    /**
     * 字节数组转换为十六进制字符串
     *
     * @param b
     *            byte[] 需要转换的字节数组
     * @return String 十六进制字符串
     */
    public static String byteToHex(byte b[]) {
        if (b == null) {
            throw new IllegalArgumentException(
                    "Argument b ( byte array ) is null! ");
        }
        String hs = "";
        String stmp = "";
        for (int n = 0; n < b.length; n++) {
            stmp = Integer.toHexString(b[n] & 0xff);
            if (stmp.length() == 1) {
                hs = hs + "0" + stmp;
            } else {
                hs = hs + stmp;
            }
        }
        return hs.toUpperCase();
    }

    public static byte[] subByte(byte[] input, int startIndex, int length) {
        byte[] bt = new byte[length];
        for (int i = 0; i < length; i++) {
            bt[i] = input[i + startIndex];
        }
        return bt;
    }
}

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