Welcome Guest [Log In] [Register]
Welcome to Crypto. We hope you enjoy your visit.


You're currently viewing our forum as a guest. This means you are limited to certain areas of the board and there are some features you can't use. If you join our community, you'll be able to access member-only sections, and use many member-only features such as customizing your profile, sending personal messages, and voting in polls. Registration is simple, fast, and completely free.


Join our community!


If you're already a member please log in to your account to access all of our features:

Username:   Password:
Add Reply
Base hash; Another basic cipher
Topic Started: Oct 1 2009, 12:31 PM (76 Views)
dabombguyman Oct 1 2009, 12:31 PM Post #1
Member Avatar
Just registered
[ * ]
 I was thinking about base conversion and how hex has letters in it and realized I could use every character on a keyboard and even special characters. Base 64 or 92 would be the start Base and any other base is the end. The key would be the alphabet, instead of "0123456789ABCD. . . " It could be "A8hf4BGj7kr9. . ." Making 64! or 92! possible keys. But you also have to guess the start and end bases making it 64! + 65! + 66! . . . N! number of key combinations. The best part is that one letter off in the alphabet and it destroys a little over half of the plain and cipher texts. Although if your message is short then you wont likely use that one letter they get wrong making it easier to find the right key but the fact that your message is short makes it more difficult to know when you've found the right key. The opposite when your message size increases, it's easy to know when you got the right key but harder to get there because it's less likely that you'll get it.

When I was programing a javascript version of this I tested it and found that it can't count big numbers, do math functions on them and keep them out of scientific notation (drops alot of the message), If anyone can help me with this I would appreciate it.

It is likely that a cipher so simple has huge holes in it, so let me know what you find. :)
Q3J5cHRvZ3JhcGh5IGlzIGFuIGFydCBmb3Jt
Offline Profile Quote Post Goto Top
 
jdege Oct 1 2009, 05:18 PM Post #2
Member Avatar
Elite member
[ * * * * * ]
 In Java the int data type is restricted to 2^32. The double only represents approximate values.

What you want is the java.math.BigInteger class.

http://java.sun.com/j2se/1.4.2/docs/api/java/math/BigInteger.html
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.
Offline Profile Quote Post Goto Top
 
dabombguyman Oct 2 2009, 12:03 AM Post #3
Member Avatar
Just registered
[ * ]
 Not sun java. Javascript like for websites. They're two different things.

Here's my code.
Code:
 
function[space]encrypt()
{
[space]var[space]alpha,bo,bt,ptext,L,A,M,ctext,b;
[space]alpha="0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ[space].abcdefghijklmnopqrstuvwxyz`~!@#$%^&*()-_=+[{]}\|;:',<>/?";
[space]bo=eval(document.dencoder.b1.value);
[space]bt=eval(document.dencoder.b2.value);
[space]ptext=document.dencoder.texte.value;
[space]L=ptext.length;
[space]A=0;
[space]for(M=0;M<=L-1;M+0)
[space][space]{
[space][space]A=[space]Math.pow(bo,(L-1)-M)*(alpha.indexOf(ptext.substr(M,1)))+A;
[space][space][space]document.dencoder.textf.value=document.dencoder.textf.value+","+A;
[space][space][space]M=[space]M+1
[space][space]}
[space]ctext="";
[space]J=Math.floor(Math.log(A)/Math.log(bt));
[space]while(A[space]!=[space]0)
[space][space]{
[space][space][space]ctext=alpha.substr(A%bt,1)+ctext;
[space][space][space]A=[space]Math.floor(A/bt);
[space][space]}
[space]document.dencoder.textf.value=ctext;
}

function[space]decrypt()
{
[space]var[space]alpha,bo,bt,ptext,L,A,M,ctext,b;
[space]alpha="0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ[space].abcdefghijklmnopqrstuvwxyz`~!@#$%^&*()-_=+[{]}\|;:',<>/?";
[space]bo=eval(document.dencoder.b2.value);
[space]bt=eval(document.dencoder.b1.value);
[space]ptext=document.dencoder.textf.value;
[space]L=ptext.length;
[space]A=0;
[space]for(M=0;M<=L-1;M+0)
[space][space]{
[space][space]A=[space]Math.pow(bo,(L-1)-M)*(alpha.indexOf(ptext.substr(M,1)))+A;
[space][space][space]document.dencoder.texte.value=document.dencoder.texte.value+","+A;
[space][space][space]M=[space]M+1
[space][space]}
[space]ctext="";
[space]J=Math.floor(Math.log(A)/Math.log(bt));
[space]while(A[space]!=[space]0)
[space][space]{
[space][space][space]ctext=alpha.substr(A%bt,1)+ctext;
[space][space][space]A=[space]Math.floor(A/bt);
[space][space]}
[space]document.dencoder.texte.value=ctext;
}

and the html that goes with it.
Code:
 
<html><head>
<meta[space]http-equiv="content-type"[space]content="text/html;[space]charset=ISO-8859-1">

<meta[space]name="description"[space]content="Base-hash[space]Cipher">
<title>Arcanum[space]Cipher</title>

<script[space]type="text/javascript"[space]language="javascript"[space]src="Basehash.js"></script>
[space][space][space][space][space][space][space]
</head><body> 


[space][space][space][space][space]


<table>
<tbody><tr><td[space]width="35%"></td>
[space][space][space][space][space][space]<td[space]valign="top">
[space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space][space]
[space][space][space][space][space][space][space][space]<div[space]style="padding:[space]2px[space]5px[space]2px[space]20px;"[space]class="titlebg0"><center><b>Base-hash[space]Cipher[space]Tool</b></center></div>

[space][space][space][space][space][space][space][space]<div[space]class="windowbg02"[space]style="padding:[space]10px;">
[space][space][space][space][space][space][space][space][space][space]<div[space]style="padding:[space]5px;[space]width:[space]300px;">


<form[space]name="dencoder">[space]


<p><b>Plaintext:</b>

<table[space]class="phtable2"[space]style="margin-top:[space]4px;[space]margin-bottom:[space]8px;"><tbody><tr><td><textarea[space]name="texte"[space]rows="5"[space]cols="50"[space]value="">text[space]to[space]be[space]encoded</textarea></td></tr></tbody></table>

</p><p><b>Base1:</b>
<table[space]class="phtable2"[space]style="margin-top:[space]4px;[space]margin-bottom:[space]8px;"><tbody><tr><td><textarea[space]name="b1"[space]rows="1"[space]cols="50"[space]value="">Key</textarea></td></tr></tbody></table>

</p><p><b>Base2:</b>
<table[space]class="phtable2"[space]style="margin-top:[space]4px;[space]margin-bottom:[space]8px;"><tbody><tr><td><textarea[space]name="b2"[space]rows="1"[space]cols="50"[space]value="">Key</textarea></td></tr></tbody></table>

       
<input[space]onclick="encrypt()"[space]value="Encode"[space]type="button">
                          
<input[space]onclick="decrypt()"[space]value="Decode"[space]type="button">

</p><p><b>Ciphertext:</b>
<table[space]class="phtable2"[space]style="margin-top:[space]4px;[space]margin-bottom:[space]8px;"><tbody><tr><td><textarea[space]name="textf"[space]rows="5"[space]cols="50"[space]value="">text[space]to[space]be[space]decoded</textarea></td></tr></tbody></table>


<input[space]name="clear"[space]value="Clear"[space]onclick="this.form.texte.value='Text[space]to[space]be[space]encoded';[space]this.form.textf.value='Text[space]to[space]be[space]decoded'"[space]type="button">


</p></form></div>



</div></td>
<td[space]width="35%"></td></tr></tbody></table>




[space][space][space][space][space][space][space][space]
[space][space][space]
[space][space]
</body></html>


Here is the site Click here..
Is it possible to port this code?

Also, anyone know any ways to break this cipher?
Q3J5cHRvZ3JhcGh5IGlzIGFuIGFydCBmb3Jt
Offline Profile Quote Post Goto Top
 
jdege Oct 4 2009, 09:46 PM Post #4
Member Avatar
Elite member
[ * * * * * ]
 Is this working for you? Because when I encryt some text, then decrypt the result, I'm getting a bunch of numbers, not my original text.
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.
Offline Profile Quote Post Goto Top
 
dabombguyman Oct 5 2009, 10:17 PM Post #5
Member Avatar
Just registered
[ * ]
 As I said, it doesn't work with big numbers because javascript has a limit on size. I'm wondering if there is a work around.

Also, did you set the first base 64?
Q3J5cHRvZ3JhcGh5IGlzIGFuIGFydCBmb3Jt
Offline Profile Quote Post Goto Top
 
1 user reading this topic (1 Guest and 0 Anonymous)
« Previous Topic · General · Next Topic »
Add Reply