Secure Your Portable Device
PicoCrypt is a small encryption and decryption tool. It can be used to encrypt any kind of file. It is a small programme (16 KB) that runs without an installation, and can be carried around on a USB drive. When used to encrypt a file, the file will be visible, but not readable. An image or a text file will appear garbled or as gibberish. Some kinds of extensions cannot be opened at all. However, the thumbnail of the document will be visible if Windows has the thumbnail saved before the file was encrypted. Also, users can delete the file from the system if they want to. To encrypt a file, simple drag and drop it into PicoCrypt. A window will ask you if you want to encrypt or decrypt the file. Click on encrypt. You will be prompted for a password, and a confirmation. If you drag and drop multiple files into PicoCrypt, you will be prompted to enter a password and confirm it for each of the files dragged into PicoCrypt. To view the files again, start up PicoCrypt, and drag and drop the files you want to decrypt, then enter the passwords for each of them in turn. Now the files can be opened and edited on programmes.
Another simple way to protect files is to put them in an encrypted archive. This is essentially the same as the above method, but the extension is changed to archive format, such as a ZIP file. We will be using a free and open source archiving software called 7zip. 7zip stores archives in the .7z format by default, but also works with BZip2, GZip, TAR and ZIP formats. WinRar is a great software for handling archive files, but you have to purchase the full version before you can password protect your archives. Once you install 7zip, the archiving operations show up in the context menu when you right click on a file or folder you want to archive. Right-click and select “add to archive”. In the Encryption field, enter a password, and enter it again. If you check the “Show password” checkbox, you don’t need to enter the password twice. In the Archive Format drop down menu, select the archive format you want to use. 7zip portable and one of the more obscure formats, will discourage casual snoopers. If anyone wants to access the contents of the archive, they will need the password. This is a great way of sharing files over public hosting services, such as yousendit or rapidshare.
copy /b image.jpg + archive.7z image2.jpg
The image2.jpg will be the image file with the hidden archive. To extract the archive, change the extension of the file from image2.jpg to archive.7z. Note that you need to remember the format the archive was originally in. Using a .zip extension for a .7z archive won’t work. The image2.jpg file can be opened in image viewers, and even in image manipulation programs. The archive will get corrupted only if the image file is overwritten with changes.
Sometimes it is necessary to hide or lock away entire folders. When working regularly with files, the above methods are not of much help, and are pretty laborious.
TrueCrypt is a great open source encryption software for such purposes. When installing TrueCrypt, there are two options available. A disk installation will install the software on the hard drive. An extraction, will however place the software on an external drive, and can be run from there. This is essentially a portable version of TrueCrypt, but this version is limited in capability. After you encrypt a drive in TrueCrypt, the computer will recognize a plugged in drive, but not allow you to access it. Instead, any computer will prompt you to format the drive before you can use it. TrueCrypt can be used to mount the drive, which means that the same drive will occupy to drive letters. The default one will be inaccessible and the mounted drive will be available only after you enter the password in TrueCrypt. TrueCrypt is available for Linux and Mac systems as well, so your encrypted drive will be truly portable.
The next step is to select the drive or device that you want to encrypt and password protect. Click on Device, and select a device from the list that appears, then click on Next. The next step allows you to either format the device and encrypt it, or encrypt the partition in place. The first option simply erases all the data on the partition, then encrypts it. The second option, encrypts the drive, moves the data around, and encrypts the data as well. The second option is very time consuming, and it is faster to copy the data to a secure location, format and encrypt the drive, then copy the data back to the volume. Select Create encrypted volume and format it, then click on Next.
The size prompt box now appears. This is useful only for creating containers, or volumes hidden within a file. The size of the drive will show up in this window, and you cannot change the values. Click on Next. You have to enter a password and confirm it at this stage. If you use anything less than a password of 20 strings in length, TrueCrypt will prompt you to choose a more secure passwords. A ten character password or so should be beyond what a casual snooper can crack using a brute force method, which is trying every possible combination of letters and numbers as the password. Next you will be asked to move the cursor around the window in a random way. This just generates random strings of data that will be used in the encryption. Click on Format after this is done.