Text Shredder is a utility that simplifies encryption and decryption of plain text data. Plain text data is encrypted and can then be easily copied to the clipboard or saved as a text file. This text file can then be sent via your normal instant chat/messenger programs or email. Text Shredder is released as Open Source under the GPL v3.0 License.
Text Shredder allows you to set up to 2 passwords (the 2nd password is optional). These passwords are then used to create a strong encryption key which is used to encrypt your text using the industry standard FIPS Certified AES algorithm (Advanced Security Standard).
Why Text Shredder
Another reason to use Text Shredder is that you may not have administrative rights on the machine you need to send messages from. Tools like GPG4Win require admin rights on the machine to run the installer. Text Shredder is truly portable, you do not need to run an installer file and you do not need administrative privileges to run the tool. Tools like GPG4Win, whilst they are very good they can be quite tricky to set-up for people who are not experienced in dealing with security certificates etc. Text Shredder is designed to be very easy to use by just about anyone, even with only very basic computing skills.
Text Shredder is a simple utility that allows you to encrypt text using industry standard FIPS Certified AES Encryption algorithms. You can then paste this encrypted text or text file into you email or chat messages. This essentially gives you another layer of message based security on top of what is already provided.
How to Install Text Shredder
Installing Text Shredder is very easy. Once you have downloaded the application from the main website, you need to unzip the file using a tool like WinZip, 7Zip or WinRAR. This will put all of the application files into a folder. Text Shredder is a portable application. This means there is no installer program that you need to run. One of the advantages of Text Shredder is that you can set it up and run it without administrative permissions on your computer.
To run Text Shredder you double click on the Text Shredder application icon as highlighted above. You can pin this to your task bar or add it to your start button (windows 7), or start screen (windows 8).
Basic Operation of Text Shredder
Once Text Shredder loads up, you will first be prompted to enter 1 or more passwords. You do not have to enter the 2nd password if you don’t want to use one. The idea behind the 2nd password is that it is likely easier for a user to remember 2 fairly strong passwords over 1 very strong password. This entirely depends on the user and may not necessarily be the case for everyone, hence the 2nd password being optional.
Once you have entered a password(s), and you click on OK, you will be prompted to enter them again for verification. This is to ensure you didn’t type the initial password(s) incorrectly. This helps to ensure that when you encrypt your first message that the recipient would be able to decrypt it, as they will be using the same passwords.
Password entry is generally done by using your computer keyboard. If you are using a public PC, say in a library, or internet café, and you don not trust that there are no key loggers installed on the system, you can use an on-screen and the mouse to enter the password(s). This avoids you typing the password using the physical keyboard and therefore having the keys logged somewhere for someone to recover the password.
Once you have entered and verified your passwords you will see ‘Password Set’ appears in the status bar (see above). This means the password has been successfully entered and verified. The process for encrypting, Sending, Receiving, Decrypting passwords is illustrated in the diagram below.
As you can see from the illustration above, the process of message exchange is quite straight forward.
Encrypting a Message
Make sure the ‘Encrypt’ Tab is selected and then type the message you want to send in the ‘Text to Encrypt’ text box.
The encrypted text should appear as a series of random looking numbers and letters, as shown below. If you hit the Encrypt button again, the encrypted text will change. This is due to the way Text Shredder has been implemented, so that the encrypted message changes every-time you encrypt it. This helps guard you from attacks against the known cipher text if you send the same message twice.
Now that the message has been encrypted you can either select the text in the window and copy it to the clipboard by pressing CTRL and C, or right clicking in the text box and selecting ‘Copy’. You can also press the ‘Copy Encrypted to Clipboard’ button which will do the same thing. If you don’t want to paste the actual encrypted text into an email, you can save it to a file by going to the File menu and selecting the ‘Save Encrypted Text File’ option.
The ‘Clear All’ button will delete the text from both text boxes. This is useful If there is someone walking around near you when you are encoding messages with the application. If you select the ‘Delete Text After Encrypt’ check box, then the original un-encrypted message will be remove from the display once you have pressed ‘Encrypt’ and the encrypted message is generated.
Decrypting a Message
When you receive an encrypted message, you need to start-up Text Shredder and enter the same passwords as the original sender. Then make sure the Decrypt Tab is selected.
Next you need to paste the encrypted text from your email or chat program into the ‘Text to Decrypt’ text box. You can also load up a text file of encrypted text from the File menu. Once you are ready to decrypt the text, press the ‘Decrypt’ button on the bottom right hand side of the window. This will encrypt the text using the provided passwords.
You must make sure you copy and paste the exact encrypted text from your email or chat program. If you miss any of the message off or change any of the characters by mistake you will receive an error message. Also, if your message is intercepted in transit and changed, then you will also receive an error message (like below).
Text Shredder has an inbuilt safety mechanism call an Authenticated Message Code. This means the message is protected from tampering when it is first encrypted. When you go to decrypt the message, if any of the message was changed whilst it was being sent to you, the authenticated message code will not match which indicates the message has been corrupted or tampered with.
At the bottom of the decryption window, there are some additional buttons. The ‘Paste Encrypted Text from Clipboard’ will paste any text from the clipboard into the ‘Text to Decrypt’ text box. The ‘Delete Plain Text’ button will remove the decrypted text from the screen. This is useful, if you want to quickly read the message and the remove it from view. Finally, the ‘Clear All’ button will empty both text boxes.
Text Shredder has some basic themes build in to help give you some privacy when using the application on a machine in a busy environment. If you go to the ‘Theme’ menu, you are presented with 3 options.
- Low Contrast (Dark)
- Low Contrast (Light)
The low contrast options change the text boxes so that there is not much contrast between the background and foreground colours. This makes it difficult for anyone to read over your shoulder if they are standing behind you or to the side.
What ever theme you select will be remembered when you close the application. This means when you load up Text Shredder again in the future, it will start with the same theme.