今天在做一个老项目时，遇到一个需求，在javascript将url中的参数加密解密，从网上找发现了这段有用的代码：
- <SCRIPT LANGUAGE="JavaScript">
-
- <!-- Begin
-
-
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- function Encrypt(str, pwd) {
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- if(str=="")return "";
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- str = escape(str);
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- if(!pwd || pwd==""){ var pwd="1234"; }
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- pwd = escape(pwd);
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- if(pwd == null || pwd.length <= 0) {
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- alert("Please enter a password with which to encrypt the message.");
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- return null;
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- }
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- var prand = "";
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- for(var I=0; I<pwd.length; I++) {
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- prand += pwd.charCodeAt(I).toString();
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- }
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- var sPos = Math.floor(prand.length / 5);
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- var mult = parseInt(prand.charAt(sPos) + prand.charAt(sPos*2) + prand.charAt(sPos*3) + prand.charAt(sPos*4) + prand.charAt(sPos*5));
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-
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- var incr = Math.ceil(pwd.length / 2);
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- var modu = Math.pow(2, 31) - 1;
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- if(mult < 2) {
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- alert("Algorithm cannot find a suitable hash. Please choose a different password. /nPossible considerations are to choose a more complex or longer password.");
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- return null;
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- }
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- var salt = Math.round(Math.random() * 1000000000) % 100000000;
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- prand += salt;
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- while(prand.length > 10) {
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- prand = (parseInt(prand.substring(0, 10)) + parseInt(prand.substring(10, prand.length))).toString();
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- }
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- prand = (mult * prand + incr) % modu;
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- var enc_chr = "";
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- var enc_str = "";
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- for(var I=0; I<str.length; I++) {
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- enc_chr = parseInt(str.charCodeAt(I) ^ Math.floor((prand / modu) * 255));
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- if(enc_chr < 16) {
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- enc_str += "0" + enc_chr.toString(16);
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- }else
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- enc_str += enc_chr.toString(16);
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- prand = (mult * prand + incr) % modu;
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- }
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- salt = salt.toString(16);
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- while(salt.length < 8)salt = "0" + salt;
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- enc_str += salt;
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- return enc_str;
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- }
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-
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- function Decrypt(str, pwd) {
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- if(str=="")return "";
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- if(!pwd || pwd==""){ var pwd="1234"; }
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- pwd = escape(pwd);
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- if(str == null || str.length < 8) {
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- alert("A salt value could not be extracted from the encrypted message because it‘s length is too short. The message cannot be decrypted.");
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- return;
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- }
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- if(pwd == null || pwd.length <= 0) {
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- alert("Please enter a password with which to decrypt the message.");
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- return;
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- }
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- var prand = "";
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- for(var I=0; I<pwd.length; I++) {
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- prand += pwd.charCodeAt(I).toString();
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- }
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- var sPos = Math.floor(prand.length / 5);
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- var mult = parseInt(prand.charAt(sPos) + prand.charAt(sPos*2) + prand.charAt(sPos*3) + prand.charAt(sPos*4) + prand.charAt(sPos*5));
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- var incr = Math.round(pwd.length / 2);
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- var modu = Math.pow(2, 31) - 1;
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- var salt = parseInt(str.substring(str.length - 8, str.length), 16);
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- str = str.substring(0, str.length - 8);
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- prand += salt;
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- while(prand.length > 10) {
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- prand = (parseInt(prand.substring(0, 10)) + parseInt(prand.substring(10, prand.length))).toString();
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- }
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- prand = (mult * prand + incr) % modu;
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- var enc_chr = "";
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- var enc_str = "";
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- for(var I=0; I<str.length; I+=2) {
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- enc_chr = parseInt(parseInt(str.substring(I, I+2), 16) ^ Math.floor((prand / modu) * 255));
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- enc_str += String.fromCharCode(enc_chr);
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- prand = (mult * prand + incr) % modu;
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- }
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- return unescape(enc_str);
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- }
-
-
- </script>
以后碰到加密解密问题，直接将上述代码写成一个js文件，就搞定。省事了。。。。
一段有用的javascript加密解密
原文：http://www.cnblogs.com/xiaochao12345/p/4039822.html
