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CRYPTOPAD

Sending encrypted mail is a difficult proposition if u don't have fancy mail clients. Most people tend to use web-based clients like Hotmail, Netaddress, Juno... to send personal mails, decisions, financial data etc.

One can attach encypted attachments but the mail itself is not encrypted, and worse thing is that any body with slightest knowledge of browsers can rummage through the browsers cache and read these mails.

Cryptopad is a small Java Applet/HTML page combo which intends to solve this problem.

Although the idea is to send mails, it can be used to encrypt any text. The sender and receiver need to have access to this small html page (available for free download, or use it online at this site).

The sender writes the mail in the pad (or paste it from any text editor ) keys in the encryption key and press the Encrypt button. The text will be encrypted using powerfulllll DES based Encryption. The encrypted data is converted into a text based format so that it can be copy/pasted in any program or e-mail client.

The receiver receives the encrypted text. This has to be copy/pasted into the textarea of CRYPTOPAD, key in the encryption code and press Decrypt.
The receiver needs to know the key with which the message was encrypted
In case the mail is sent using HTTP mail (Hotmail, etc.), the browsers cache only the encrypted message and nobody can decrypt it without the key.
TRY IT NOW

CRYPTOPAD (C) 1999 - 2001, Copyright mandar.s@usa.net
Enter Encryption Key-->
Enter(/Paste) your text below:
Do not forget the encryption key.

(C) 2000, Copyright mandar.s@usa.net. http://mandars.home.dhs.org


Cryptopad Help


How to Encrypt?

  • Type your message/text. OR the message can be copy/pasted from other text editors.
  • Enter the encryption key. The key can be maximum 8 characters wide.
  • It is advisable to use the full 8 character keys.
  • Press the "Encrypt" button.
  • A header
    ^ENCMVSSTART^---------------------------------------------------
    is added to the encrypted text and a footer
    ^ENCMVSEND ^---------------------------------------------------
    is suffixed.
  • The encrypted text contains only ASCII text and can be copy / pasted into any applciation. It can be pasted into the client (even send it through Hotmail, USA.net or any web basied email).
  • The receiver of the mail has to copy/paste the encrypted message into Cryptopad and key in the Encryption Key and press Decrypt button.

How to Decrypt?

  • The receiver of the message needs to know the key and have access Cryptopad to decrypt the message.
  • Copy/paste the encrypted text into the text area. Take care to select the text including the prefix
  • ^ENCMVSSTART^---------------------------------------------------
  • and the suffix ^ENCMVSEND ^---------------------------------------------------
  • Enter the encryption key which was used to encrypt the message.
  • Press the "Decrypt" button.
WARNING: If you use the wrong key the browser may garble the page due to presense of unprintable characters

Cryptopad: How it works

(For techies only )
Cryptopad uses DES algorithm for the basic encryption of text. A shared key is used to encrypt and decrypt the message i.e. the sender and the receiver need to know the encryption key.
The HTML page contains an Java Applet which contanis the DES implementation and exposes two methods one to encrypt and the message and other to decrypt the message.
The basic DES encryptor generates the encrypted stream. Such a stream can contain non printable characters, so the applet converts this byte stream into printable characters by replacing the byte value and converting it to its hexadecimal string value.

e.g. if the encrypted byte is 32 it is converted to 3332
33 is the hex representation of ASCII value of 3

The encrypted string is twice the size of the original string.
The applet adds prefix and suffix delimiters, carriage returns so that the encrypted text can be copy/pasted into other application.

CRYTOPAD Download
Brief  Description:  HTML/Java based DES encryption utility
Name cryptopad.zip
Size 18Kb
OS/Browser Browsers with JAVA>v1.1 and Javascript >v1.1 support
Language support Tested only with English i.e. (non-UNICODE character sets) on Windows Platform
In case u use it successfully with other languages please let me know.
Distribution  Freeware
DOWNLOAD cryptopad.zip
Zip file contains one HTML file (cryptopad.html) and a JAVA applet class file (mvsdes2.class)
Unzip them in a single directory and open the HTML file in any browser (IE v>4.0 and Netscape v>4.0)

This site http://mandars.home.dhs.org

(c) Copyright, 1999 - 2001 Mandar V. Samant
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