常用加密

项目最近竣工了,所以会比较闲,自己总结一下所用到的加密,仅供参考

1.首先,md5加密是常用的对密码进行加密,我们用到的是md5在前台二次加密(未使用加盐加密)传到后台进行校验,最好使用一下加盐加密,可以百度一下,相关代码如下:

public class MD5Util {/***      * MD5加码 生成32位md5码      */      public static String string2MD5(String inStr){          MessageDigest md5 = null;          try{              md5 = MessageDigest.getInstance("MD5");          }catch (Exception e){              System.out.println(e.toString());              e.printStackTrace();              return "";          }          char[] charArray = inStr.toCharArray();          byte[] byteArray = new byte[charArray.length];            for (int i = 0; i < charArray.length; i++)              byteArray[i] = (byte) charArray[i];          byte[] md5Bytes = md5.digest(byteArray);          StringBuffer hexValue = new StringBuffer();          for (int i = 0; i < md5Bytes.length; i++){              int val = ((int) md5Bytes[i]) & 0xff;              if (val < 16)                  hexValue.append("0");              hexValue.append(Integer.toHexString(val));          }          return hexValue.toString();        }        /**      * 加密解密算法 执行一次加密，两次解密      */       public static String convertMD5(String inStr){            char[] a = inStr.toCharArray();          for (int i = 0; i < a.length; i++){              a[i] = (char) (a[i] ^ 't');          }          String s = new String(a);          return s;        }        // 测试主函数      public static void main(String args[]) {          String s = new String("111111");          System.out.println("原始：" + s);          System.out.println("MD5后：" + string2MD5(s));          System.out.println("两次MD5后：" + string2MD5(string2MD5(s)));          System.out.println("加密的：" + convertMD5(s));          System.out.println("解密的：" + convertMD5("BBBBBB"));      }  }

2.base64加密,我们主要用来传输图片的时候使用base64进行加密传递

相关代码如下:

public final class Base64 {    static private final int     BASELENGTH           = 128;    static private final int     LOOKUPLENGTH         = 64;    static private final int     TWENTYFOURBITGROUP   = 24;    static private final int     EIGHTBIT             = 8;    static private final int     SIXTEENBIT           = 16;    static private final int     FOURBYTE             = 4;    static private final int     SIGN                 = -128;    static private final char    PAD                  = '=';    static private final boolean fDebug               = false;    static final private byte[]  base64Alphabet       = new byte[BASELENGTH];    static final private char[]  lookUpBase64Alphabet = new char[LOOKUPLENGTH];    static {        for (int i = 0; i < BASELENGTH; ++i) {            base64Alphabet[i] = -1;        }        for (int i = 'Z'; i >= 'A'; i--) {            base64Alphabet[i] = (byte) (i - 'A');        }        for (int i = 'z'; i >= 'a'; i--) {            base64Alphabet[i] = (byte) (i - 'a' + 26);        }        for (int i = '9'; i >= '0'; i--) {            base64Alphabet[i] = (byte) (i - '0' + 52);        }        base64Alphabet['+'] = 62;        base64Alphabet['/'] = 63;        for (int i = 0; i <= 25; i++) {            lookUpBase64Alphabet[i] = (char) ('A' + i);        }        for (int i = 26, j = 0; i <= 51; i++, j++) {            lookUpBase64Alphabet[i] = (char) ('a' + j);        }        for (int i = 52, j = 0; i <= 61; i++, j++) {            lookUpBase64Alphabet[i] = (char) ('0' + j);        }        lookUpBase64Alphabet[62] = (char) '+';        lookUpBase64Alphabet[63] = (char) '/';    }    private static boolean isWhiteSpace(char octect) {        return (octect == 0x20 || octect == 0xd || octect == 0xa || octect == 0x9);    }    private static boolean isPad(char octect) {        return (octect == PAD);    }    private static boolean isData(char octect) {        return (octect < BASELENGTH && base64Alphabet[octect] != -1);    }    /**加密     * Encodes hex octects into Base64     *     * @param binaryData Array containing binaryData     * @return Encoded Base64 array     */    public static String encode(byte[] binaryData) {        if (binaryData == null) {            return null;        }        int lengthDataBits = binaryData.length * EIGHTBIT;        if (lengthDataBits == 0) {            return "";        }        int fewerThan24bits = lengthDataBits % TWENTYFOURBITGROUP;        int numberTriplets = lengthDataBits / TWENTYFOURBITGROUP;        int numberQuartet = fewerThan24bits != 0 ? numberTriplets + 1 : numberTriplets;        char encodedData[] = null;        encodedData = new char[numberQuartet * 4];        byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0;        int encodedIndex = 0;        int dataIndex = 0;        if (fDebug) {            System.out.println("number of triplets = " + numberTriplets);        }        for (int i = 0; i < numberTriplets; i++) {            b1 = binaryData[dataIndex++];            b2 = binaryData[dataIndex++];            b3 = binaryData[dataIndex++];            if (fDebug) {                System.out.println("b1= " + b1 + ", b2= " + b2 + ", b3= " + b3);            }            l = (byte) (b2 & 0x0f);            k = (byte) (b1 & 0x03);            byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);            byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);            byte val3 = ((b3 & SIGN) == 0) ? (byte) (b3 >> 6) : (byte) ((b3) >> 6 ^ 0xfc);            if (fDebug) {                System.out.println("val2 = " + val2);                System.out.println("k4   = " + (k << 4));                System.out.println("vak  = " + (val2 | (k << 4)));            }            encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];            encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];            encodedData[encodedIndex++] = lookUpBase64Alphabet[(l << 2) | val3];            encodedData[encodedIndex++] = lookUpBase64Alphabet[b3 & 0x3f];        }        // form integral number of 6-bit groups        if (fewerThan24bits == EIGHTBIT) {            b1 = binaryData[dataIndex];            k = (byte) (b1 & 0x03);            if (fDebug) {                System.out.println("b1=" + b1);                System.out.println("b1<<2 = " + (b1 >> 2));            }            byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);            encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];            encodedData[encodedIndex++] = lookUpBase64Alphabet[k << 4];            encodedData[encodedIndex++] = PAD;            encodedData[encodedIndex++] = PAD;        } else if (fewerThan24bits == SIXTEENBIT) {            b1 = binaryData[dataIndex];            b2 = binaryData[dataIndex + 1];            l = (byte) (b2 & 0x0f);            k = (byte) (b1 & 0x03);            byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);            byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);            encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];            encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];            encodedData[encodedIndex++] = lookUpBase64Alphabet[l << 2];            encodedData[encodedIndex++] = PAD;        }        return new String(encodedData);    }    /**解密     * Decodes Base64 data into octects     *     * @param encoded string containing Base64 data     * @return Array containind decoded data.     */    public static byte[] decode(String encoded) {        if (encoded == null) {            return null;        }        char[] base64Data = encoded.toCharArray();        // remove white spaces        int len = removeWhiteSpace(base64Data);        if (len % FOURBYTE != 0) {            return null;//should be divisible by four        }        int numberQuadruple = (len / FOURBYTE);        if (numberQuadruple == 0) {            return new byte[0];        }        byte decodedData[] = null;        byte b1 = 0, b2 = 0, b3 = 0, b4 = 0;        char d1 = 0, d2 = 0, d3 = 0, d4 = 0;        int i = 0;        int encodedIndex = 0;        int dataIndex = 0;        decodedData = new byte[(numberQuadruple) * 3];        for (; i < numberQuadruple - 1; i++) {            if (!isData((d1 = base64Data[dataIndex++])) || !isData((d2 = base64Data[dataIndex++]))                || !isData((d3 = base64Data[dataIndex++]))                || !isData((d4 = base64Data[dataIndex++]))) {                return null;            }//if found "no data" just return null            b1 = base64Alphabet[d1];            b2 = base64Alphabet[d2];            b3 = base64Alphabet[d3];            b4 = base64Alphabet[d4];            decodedData[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);            decodedData[encodedIndex++] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));            decodedData[encodedIndex++] = (byte) (b3 << 6 | b4);        }        if (!isData((d1 = base64Data[dataIndex++])) || !isData((d2 = base64Data[dataIndex++]))) {            return null;//if found "no data" just return null        }        b1 = base64Alphabet[d1];        b2 = base64Alphabet[d2];        d3 = base64Data[dataIndex++];        d4 = base64Data[dataIndex++];        if (!isData((d3)) || !isData((d4))) {//Check if they are PAD characters            if (isPad(d3) && isPad(d4)) {                if ((b2 & 0xf) != 0)//last 4 bits should be zero                {                    return null;                }                byte[] tmp = new byte[i * 3 + 1];                System.arraycopy(decodedData, 0, tmp, 0, i * 3);                tmp[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);                return tmp;            } else if (!isPad(d3) && isPad(d4)) {                b3 = base64Alphabet[d3];                if ((b3 & 0x3) != 0)//last 2 bits should be zero                {                    return null;                }                byte[] tmp = new byte[i * 3 + 2];                System.arraycopy(decodedData, 0, tmp, 0, i * 3);                tmp[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);                tmp[encodedIndex] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));                return tmp;            } else {                return null;            }        } else { //No PAD e.g 3cQl            b3 = base64Alphabet[d3];            b4 = base64Alphabet[d4];            decodedData[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);            decodedData[encodedIndex++] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));            decodedData[encodedIndex++] = (byte) (b3 << 6 | b4);        }        return decodedData;    }    /**     * remove WhiteSpace from MIME containing encoded Base64 data.     *     * @param data  the byte array of base64 data (with WS)     * @return      the new length     */    private static int removeWhiteSpace(char[] data) {        if (data == null) {            return 0;        }        // count characters that's not whitespace        int newSize = 0;        int len = data.length;        for (int i = 0; i < len; i++) {            if (!isWhiteSpace(data[i])) {                data[newSize++] = data[i];            }        }        return newSize;    }}

3.aes加密:高级加密标准（英语：Advanced Encryption Standard，缩写：AES）

主要写接口时用来解密安卓和ios传过来的参数,代码如下:

public class AesSecret {/*     * 加密用的Key 可以用26个字母和数字组成 此处使用AES-128-CBC加密模式，key需要为16位。     */    private final static String sKey = "runshengxinjishu";  //密钥runshengxinjishu    private final static String ivParameter = "2015040720150407"; //向量偏移量--使用CBC模式，需要一个向量iv，可增加加密算法的强度//2015040720150407        /** Aes加密算法      * @Description AesSecret.java      * @param sSrc  加密字符串      * @return      * @author liz      * @date 2017年5月23日下午7:07:33     */    public static String encrypt(String sSrc) throws Exception{    Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");        byte[] raw = sKey.getBytes();        SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");        IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());// 使用CBC模式，需要一个向量iv，可增加加密算法的强度        cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);        byte[] encrypted = cipher.doFinal(sSrc.getBytes("utf-8"));        //return new BASE64Encoder().encode(encrypted);// 此处使用BASE64做转码。        return Base64.encodeBase64String(encrypted);//使用commons.codec来加密       // return encrypted;           }    /** Aes解密算法      * @Description AesSecret.java      * @param sSrc //解密字符串      * @return      * @author liz      * @date 2017年5月23日下午7:07:52     */    public static String decrypt(String sSrc) throws Exception{     byte[] raw = sKey.getBytes("ASCII");         SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");         Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");         IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());         cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);         //byte[] encrypted1 = new BASE64Decoder().decodeBuffer(sSrc);// 先用base64解密         byte[] encrypted1 = Base64.decodeBase64(new String(sSrc).getBytes());//使用commons.codec来加密           //byte[] encrypted1 =AesSecret.parseHexStr2Byte(sSrc);         byte[] original = cipher.doFinal(encrypted1);         String originalString = new String(original, "utf-8");         return originalString;    }/**将二进制转换成16进制  * @param buf  * @return  */  public static String parseByte2HexStr(byte buf[]) {          StringBuffer sb = new StringBuffer();          for (int i = 0; i < buf.length; i++) {                  String hex = Integer.toHexString(buf[i] & 0xFF);                  if (hex.length() == 1) {                          hex = '0' + hex;                  }                  sb.append(hex.toUpperCase());          }          return sb.toString();  }  /**将16进制转换为二进制  * @param hexStr  * @return  */  public static byte[] parseHexStr2Byte(String hexStr) {          if (hexStr.length() < 1)                  return null;          byte[] result = new byte[hexStr.length()/2];          for (int i = 0;i< hexStr.length()/2; i++) {                  int high = Integer.parseInt(hexStr.substring(i*2, i*2+1), 16);                  int low = Integer.parseInt(hexStr.substring(i*2+1, i*2+2), 16);                  result[i] = (byte) (high * 16 + low);          }          return result;  }/** 获取app传来的加密参数，并把它解密成为json对象  * @Description AesSecret.java  * @param str //app传过来加密后的字符串  * @return  * @author liz  * @date 2017年5月23日下午4:11:43 */public static JSONObject getJson (String str) throws Exception{//解密  String DeString = decrypt(str);System.out.println("解密后的字串是：" + DeString);JSONObject json = new JSONObject(new String(DeString));return json;}   public static void main(String[] args) throws Exception {       // 需要加密的字串       String cSrc = "{userPhone:15555555555,passWord:111111}";              // 加密       long lStart = System.currentTimeMillis();       String enString = encrypt(cSrc);       System.out.println("加密后的字串是：" + enString);       long lUseTime = System.currentTimeMillis() - lStart;       System.out.println("加密耗时：" + lUseTime + "毫秒");       // 解密       lStart = System.currentTimeMillis();       String DeString = decrypt(enString);       System.out.println("解密后的字串是：" + DeString);              lUseTime = System.currentTimeMillis() - lStart;       System.out.println("解密耗时：" + lUseTime + "毫秒");              //直接测试加密后的字符串测试       String test = decrypt("6cDllG7cu7aF5ZAZ5hb2Mrpu2udrxxSF1ITfb0/4nvDuNj1D6m0QrIUrKHM+SKNC");       System.out.println("解密后的字串是：" + test);       JSONObject json = new JSONObject(new String(test));       System.out.println(json.get("userPhone"));   }}

4.还有一些数据库加密和支付宝加密就不在一一列举.感兴趣可以百度一下