Javascript encrypts and decrypts the parameter code in the url.

Javascript encrypts and decrypts the parameter code in the url.

Today, when I was working on an old project, I encountered a need to encrypt and decrypt the parameters in the url in javascript. I found this useful code from the Internet:

Copy codeThe Code is as follows:
<Script language = "JavaScript">
<! -- Begin
Function Encrypt (str, pwd ){
If (str = "") return "";
Str = escape (str );
If (! Pwd | pwd = "") {var pwd = "1234 ";}
Pwd = escape (pwd );
If (pwd = null | pwd. length <= 0 ){
Alert ("Please enter a password with which to encrypt the message .");
Return null;
}
Var prand = "";
For (var I = 0; I <pwd. length; I ++ ){
Prand + = pwd. charCodeAt (I). toString ();
}
Var sPos = Math. floor (prand. length/5 );
Var mult = parseInt (prand. charAt (sPos) + prand. charAt (sPos * 2) + prand. charAt (sPos * 3) + prand. charAt (sPos * 4) + prand. charAt (sPos * 5 ));
Var incr = Math. ceil (pwd. length/2 );
Var modu = Math. pow (2, 31)-1;
If (mult <2 ){
Alert ("Algorithm cannot find a suitable hash. Please choose a different password./nPossible considerations are to choose a more complex or longer password .");
Return null;
}
Var salt = Math. round (Math. random () * 1000000000) % 100000000;
Prand + = salt;
While (prand. length> 10 ){
Prand = (parseInt (prand. substring (0, 10) + parseInt (prand. substring (10, prand. length). toString ();
}
Prand = (mult * prand + incr) % modu;
Var enc_chr = "";
Var enc_str = "";
For (var I = 0; I <str. length; I ++ ){
Enc_chr = parseInt (str. charCodeAt (I) ^ Math. floor (prand/modu) * 255 ));
If (enc_chr <16 ){
Enc_str + = "0" + enc_chr.toString (16 );
} Else
Enc_str + = enc_chr.toString (16 );
Prand = (mult * prand + incr) % modu;
}
Salt = salt. toString (16 );
While (salt. length <8) salt = "0" + salt;
Enc_str + = salt;
Return enc_str;
}
Function Decrypt (str, pwd ){
If (str = "") return "";
If (! Pwd | pwd = "") {var pwd = "1234 ";}
Pwd = escape (pwd );
If (str = null | str. length <8 ){
Alert ("A salt value cocould not be extracted from the encrypted message because it's length is too short. The message cannot be decrypted .");
Return;
}
If (pwd = null | pwd. length <= 0 ){
Alert ("Please enter a password with which to decrypt the message .");
Return;
}
Var prand = "";
For (var I = 0; I <pwd. length; I ++ ){
Prand + = pwd. charCodeAt (I). toString ();
}
Var sPos = Math. floor (prand. length/5 );
Var mult = parseInt (prand. charAt (sPos) + prand. charAt (sPos * 2) + prand. charAt (sPos * 3) + prand. charAt (sPos * 4) + prand. charAt (sPos * 5 ));
Var incr = Math. round (pwd. length/2 );
Var modu = Math. pow (2, 31)-1;
Var salt = parseInt (str. substring (str. length-8, str. length), 16 );
Str = str. substring (0, str. length-8 );
Prand + = salt;
While (prand. length> 10 ){
Prand = (parseInt (prand. substring (0, 10) + parseInt (prand. substring (10, prand. length). toString ();
}
Prand = (mult * prand + incr) % modu;
Var enc_chr = "";
Var enc_str = "";
For (var I = 0; I <str. length; I + = 2 ){
Enc_chr = parseInt (str. substring (I, I + 2), 16) ^ Math. floor (prand/modu) * 255 ));
Enc_str + = String. fromCharCode (enc_chr );
Prand = (mult * prand + incr) % modu;
}
Return unescape (enc_str );
}
// End -->
</Script>

In the future, if you encounter encryption and decryption problems, simply write the above code into a js file. It's easy ....