前端加密MD5

今天接触了MD5加密方式，记录一下使用方法，又去搜了搜关于MD5的详细内容

MD5在vue中使用方法

1、下载MD5模块
    cnpm install md5 -S
2、引入模块
    const md5 = require("md5")
3、加密
    const str = "12345";
    console.log(md5(str))；

1.MD5介绍

MD5是MD5消息摘要算法的简称（英语：MD5 Message-Digest Algorithm），是一种广泛使用的密码散列函数，可以产生出一个128位（16字节）的散列值（即哈希值），用于确保信息传输的完整性。MD5由罗纳德·李维斯特设计，于1992年公开，用以取代MD4算法。这套算法的程序在RFC 1321 中被加以规范。将数据（如一段文字）运算变为另一固定长度值，是散列算法的基础原理。MD5已经被证实可以被碰撞破解。对于需要高度安全性的数据，专家一般建议改用其他算法，如SHA-2。

2.js加密的好处

（1）用js对私密信息加密可避免在网络中传输明文信息,被人截取数据包而造成数据泄露。

（2）避免缓存中自动缓存密码。比如在使用谷歌浏览器登陆时,输入的用户名和密码会自动缓存,下次登陆时无需输入密码就可以实现登陆,这样就给别人留下漏洞,当别人用你电脑登陆或把input的type改为test 那么你的密码就泄露了.使用js加密时,缓存的加密后的密文,用密文做密码登陆是不成功的,即使泄露也是泄露的密文,对密码不会造成威胁，缺点是每次登陆时都要手动输入密码，较麻烦。

（3）使用js加密,减少了服务器加密时的资源消耗,从理论上提高了服务器的性能。为了安全,很有必要再做服务器端的加密.无论从理论还是实际,两道门比一道门要安全些.至少给攻击者造成了一个障碍。

md5还有jQuery的使用方法

jquery.md5.js插件代码：

/**
 * jQuery MD5 hash algorithm function
 *
 *   <code>
 *     Calculate the md5 hash of a String
 *     String $.md5 ( String str )
 *   </code>
 *
 * Calculates the MD5 hash of str using the » RSA Data Security, Inc. MD5 Message-Digest Algorithm, and returns that hash.
 * MD5 (Message-Digest algorithm 5) is a widely-used cryptographic hash function with a 128-bit hash value. MD5 has been employed in a wide variety of security applications, and is also commonly used to check the integrity of data. The generated hash is also non-reversable. Data cannot be retrieved from the message digest, the digest uniquely identifies the data.
 * MD5 was developed by Professor Ronald L. Rivest in 1994. Its 128 bit (16 byte) message digest makes it a faster implementation than SHA-1.
 * This script is used to process a variable length message into a fixed-length output of 128 bits using the MD5 algorithm. It is fully compatible with UTF-8 encoding. It is very useful when u want to transfer encrypted passwords over the internet. If you plan using UTF-8 encoding in your project don't forget to set the page encoding to UTF-8 (Content-Type meta tag).
 * This function orginally get from the WebToolkit and rewrite for using as the jQuery plugin.
 *
 * Example
 *   Code
 *     <code>
 *       $.md5("I'm Persian.");
 *     </code>
 *   Result
 *     <code>
 *       "b8c901d0f02223f9761016cfff9d68df"
 *     </code>
 *
 * @alias Muhammad Hussein Fattahizadeh < muhammad [AT] semnanweb [DOT] com >
 * @link http://www.semnanweb.com/jquery-plugin/md5.html
 * @see http://www.webtoolkit.info/
 * @license http://www.gnu.org/licenses/gpl.html [GNU General Public License]
 * @param {jQuery} {md5:function(string))
 * @return string
 */
(function($){
  var rotateLeft = function(lValue, iShiftBits) {
    return (lValue << iShiftBits) | (lValue >>> (32 - iShiftBits));
  }
  var addUnsigned = function(lX, lY) {
    var lX4, lY4, lX8, lY8, lResult;
    lX8 = (lX & 0x80000000);
    lY8 = (lY & 0x80000000);
    lX4 = (lX & 0x40000000);
    lY4 = (lY & 0x40000000);
    lResult = (lX & 0x3FFFFFFF) + (lY & 0x3FFFFFFF);
    if (lX4 & lY4) return (lResult ^ 0x80000000 ^ lX8 ^ lY8);
    if (lX4 | lY4) {
      if (lResult & 0x40000000) return (lResult ^ 0xC0000000 ^ lX8 ^ lY8);
      else return (lResult ^ 0x40000000 ^ lX8 ^ lY8);
    } else {
      return (lResult ^ lX8 ^ lY8);
    }
  }
  var F = function(x, y, z) {
    return (x & y) | ((~ x) & z);
  }
  var G = function(x, y, z) {
    return (x & z) | (y & (~ z));
  }
  var H = function(x, y, z) {
    return (x ^ y ^ z);
  }
  var I = function(x, y, z) {
    return (y ^ (x | (~ z)));
  }
  var FF = function(a, b, c, d, x, s, ac) {
    a = addUnsigned(a, addUnsigned(addUnsigned(F(b, c, d), x), ac));
    return addUnsigned(rotateLeft(a, s), b);
  };
  var GG = function(a, b, c, d, x, s, ac) {
    a = addUnsigned(a, addUnsigned(addUnsigned(G(b, c, d), x), ac));
    return addUnsigned(rotateLeft(a, s), b);
  };
  var HH = function(a, b, c, d, x, s, ac) {
    a = addUnsigned(a, addUnsigned(addUnsigned(H(b, c, d), x), ac));
    return addUnsigned(rotateLeft(a, s), b);
  };
  var II = function(a, b, c, d, x, s, ac) {
    a = addUnsigned(a, addUnsigned(addUnsigned(I(b, c, d), x), ac));
    return addUnsigned(rotateLeft(a, s), b);
  };
  var convertToWordArray = function(string) {
    var lWordCount;
    var lMessageLength = string.length;
    var lNumberOfWordsTempOne = lMessageLength + 8;
    var lNumberOfWordsTempTwo = (lNumberOfWordsTempOne - (lNumberOfWordsTempOne % 64)) / 64;
    var lNumberOfWords = (lNumberOfWordsTempTwo + 1) * 16;
    var lWordArray = Array(lNumberOfWords - 1);
    var lBytePosition = 0;
    var lByteCount = 0;
    while (lByteCount < lMessageLength) {
      lWordCount = (lByteCount - (lByteCount % 4)) / 4;
      lBytePosition = (lByteCount % 4) * 8;
      lWordArray[lWordCount] = (lWordArray[lWordCount] | (string.charCodeAt(lByteCount) << lBytePosition));
      lByteCount++;
    }
    lWordCount = (lByteCount - (lByteCount % 4)) / 4;
    lBytePosition = (lByteCount % 4) * 8;
    lWordArray[lWordCount] = lWordArray[lWordCount] | (0x80 << lBytePosition);
    lWordArray[lNumberOfWords - 2] = lMessageLength << 3;
    lWordArray[lNumberOfWords - 1] = lMessageLength >>> 29;
    return lWordArray;
  };
  var wordToHex = function(lValue) {
    var WordToHexValue = "", WordToHexValueTemp = "", lByte, lCount;
    for (lCount = 0; lCount <= 3; lCount++) {
      lByte = (lValue >>> (lCount * 8)) & 255;
      WordToHexValueTemp = "0" + lByte.toString(16);
      WordToHexValue = WordToHexValue + WordToHexValueTemp.substr(WordToHexValueTemp.length - 2, 2);
    }
    return WordToHexValue;
  };
  var uTF8Encode = function(string) {
    string = string.replace(/\x0d\x0a/g, "\x0a");
    var output = "";
    for (var n = 0; n < string.length; n++) {
      var c = string.charCodeAt(n);
      if (c < 128) {
        output += String.fromCharCode(c);
      } else if ((c > 127) && (c < 2048)) {
        output += String.fromCharCode((c >> 6) | 192);
        output += String.fromCharCode((c & 63) | 128);
      } else {
        output += String.fromCharCode((c >> 12) | 224);
        output += String.fromCharCode(((c >> 6) & 63) | 128);
        output += String.fromCharCode((c & 63) | 128);
      }
    }
    return output;
  };
  $.extend({
    md5: function(string) {
      var x = Array();
      var k, AA, BB, CC, DD, a, b, c, d;
      var S11=7, S12=12, S13=17, S14=22;
      var S21=5, S22=9 , S23=14, S24=20;
      var S31=4, S32=11, S33=16, S34=23;
      var S41=6, S42=10, S43=15, S44=21;
      string = uTF8Encode(string);
      x = convertToWordArray(string);
      a = 0x67452301; b = 0xEFCDAB89; c = 0x98BADCFE; d = 0x10325476;
      for (k = 0; k < x.length; k += 16) {
        AA = a; BB = b; CC = c; DD = d;
        a = FF(a, b, c, d, x[k+0], S11, 0xD76AA478);
        d = FF(d, a, b, c, x[k+1], S12, 0xE8C7B756);
        c = FF(c, d, a, b, x[k+2], S13, 0x242070DB);
        b = FF(b, c, d, a, x[k+3], S14, 0xC1BDCEEE);
        a = FF(a, b, c, d, x[k+4], S11, 0xF57C0FAF);
        d = FF(d, a, b, c, x[k+5], S12, 0x4787C62A);
        c = FF(c, d, a, b, x[k+6], S13, 0xA8304613);
        b = FF(b, c, d, a, x[k+7], S14, 0xFD469501);
        a = FF(a, b, c, d, x[k+8], S11, 0x698098D8);
        d = FF(d, a, b, c, x[k+9], S12, 0x8B44F7AF);
        c = FF(c, d, a, b, x[k+10], S13, 0xFFFF5BB1);
        b = FF(b, c, d, a, x[k+11], S14, 0x895CD7BE);
        a = FF(a, b, c, d, x[k+12], S11, 0x6B901122);
        d = FF(d, a, b, c, x[k+13], S12, 0xFD987193);
        c = FF(c, d, a, b, x[k+14], S13, 0xA679438E);
        b = FF(b, c, d, a, x[k+15], S14, 0x49B40821);
        a = GG(a, b, c, d, x[k+1], S21, 0xF61E2562);
        d = GG(d, a, b, c, x[k+6], S22, 0xC040B340);
        c = GG(c, d, a, b, x[k+11], S23, 0x265E5A51);
        b = GG(b, c, d, a, x[k+0], S24, 0xE9B6C7AA);
        a = GG(a, b, c, d, x[k+5], S21, 0xD62F105D);
        d = GG(d, a, b, c, x[k+10], S22, 0x2441453);
        c = GG(c, d, a, b, x[k+15], S23, 0xD8A1E681);
        b = GG(b, c, d, a, x[k+4], S24, 0xE7D3FBC8);
        a = GG(a, b, c, d, x[k+9], S21, 0x21E1CDE6);
        d = GG(d, a, b, c, x[k+14], S22, 0xC33707D6);
        c = GG(c, d, a, b, x[k+3], S23, 0xF4D50D87);
        b = GG(b, c, d, a, x[k+8], S24, 0x455A14ED);
        a = GG(a, b, c, d, x[k+13], S21, 0xA9E3E905);
        d = GG(d, a, b, c, x[k+2], S22, 0xFCEFA3F8);
        c = GG(c, d, a, b, x[k+7], S23, 0x676F02D9);
        b = GG(b, c, d, a, x[k+12], S24, 0x8D2A4C8A);
        a = HH(a, b, c, d, x[k+5], S31, 0xFFFA3942);
        d = HH(d, a, b, c, x[k+8], S32, 0x8771F681);
        c = HH(c, d, a, b, x[k+11], S33, 0x6D9D6122);
        b = HH(b, c, d, a, x[k+14], S34, 0xFDE5380C);
        a = HH(a, b, c, d, x[k+1], S31, 0xA4BEEA44);
        d = HH(d, a, b, c, x[k+4], S32, 0x4BDECFA9);
        c = HH(c, d, a, b, x[k+7], S33, 0xF6BB4B60);
        b = HH(b, c, d, a, x[k+10], S34, 0xBEBFBC70);
        a = HH(a, b, c, d, x[k+13], S31, 0x289B7EC6);
        d = HH(d, a, b, c, x[k+0], S32, 0xEAA127FA);
        c = HH(c, d, a, b, x[k+3], S33, 0xD4EF3085);
        b = HH(b, c, d, a, x[k+6], S34, 0x4881D05);
        a = HH(a, b, c, d, x[k+9], S31, 0xD9D4D039);
        d = HH(d, a, b, c, x[k+12], S32, 0xE6DB99E5);
        c = HH(c, d, a, b, x[k+15], S33, 0x1FA27CF8);
        b = HH(b, c, d, a, x[k+2], S34, 0xC4AC5665);
        a = II(a, b, c, d, x[k+0], S41, 0xF4292244);
        d = II(d, a, b, c, x[k+7], S42, 0x432AFF97);
        c = II(c, d, a, b, x[k+14], S43, 0xAB9423A7);
        b = II(b, c, d, a, x[k+5], S44, 0xFC93A039);
        a = II(a, b, c, d, x[k+12], S41, 0x655B59C3);
        d = II(d, a, b, c, x[k+3], S42, 0x8F0CCC92);
        c = II(c, d, a, b, x[k+10], S43, 0xFFEFF47D);
        b = II(b, c, d, a, x[k+1], S44, 0x85845DD1);
        a = II(a, b, c, d, x[k+8], S41, 0x6FA87E4F);
        d = II(d, a, b, c, x[k+15], S42, 0xFE2CE6E0);
        c = II(c, d, a, b, x[k+6], S43, 0xA3014314);
        b = II(b, c, d, a, x[k+13], S44, 0x4E0811A1);
        a = II(a, b, c, d, x[k+4], S41, 0xF7537E82);
        d = II(d, a, b, c, x[k+11], S42, 0xBD3AF235);
        c = II(c, d, a, b, x[k+2], S43, 0x2AD7D2BB);
        b = II(b, c, d, a, x[k+9], S44, 0xEB86D391);
        a = addUnsigned(a, AA);
        b = addUnsigned(b, BB);
        c = addUnsigned(c, CC);
        d = addUnsigned(d, DD);
      }
      var tempValue = wordToHex(a) + wordToHex(b) + wordToHex(c) + wordToHex(d);
      return tempValue.toLowerCase();
    }
  });
})(jQuery);

使用方法

$.(md5("你想要加密的字符串"));

附上MD5 破解网站：https://www.cmd5.com/ （简单的可以破解，复杂的不能破解）

后来又搜到前端加密方式有很多，可以看看这位博主的文章 https://blog.csdn.net/doulinxu/article/details/60766242 ， 写的很详细！