In the last post I described how to securely and permanently remove a file from the disk drive using Eraser.

Now what happen if you need to securely store, not delete, any files? In this post, we will introduce another open source tools that will help you do just that – TrueCrypt.

With TrueCrypt you can protect your sensitive data, create a virtual encrypted disk within a file and mount it as a disk. You can also encrypt an a hard disk partition or a device, such as USB flash drive. The encryption is done automatically and transparently in real time. The author calls it an on-the-fly-encrypted volume .

Using TrueCrypt

TrypeCrypt can be a little confusing in the beginning for some user, such as the concept of mounting a disk volume (similar to using Daemons Tools). However it is worth exploring if you are looking for ways to securely store your data.

Start with the introduction to get an basic idea of the software. The Beginner’s Tutorial gives a step by step instruction on how to create a first encrypted drive.

TrueCrypt’s Features

TrueCrpyt is a very powerful software with many features for the normal user that just want to secure some file to the hyper-sensitive secret agent. For some, reading the TypeCrypt documentation is like reading a spy novel riddled with technical details.

On-the-fly-encrypted volume simply means that you do not have to decrypt a file as you access it. For example if you have a text file in a TrueCrypt volume, you can just double-click to open it. It will be decrypted behind the scene and encrypted again as you save and close the file.

Plausible deniability is an interesting concept where hidden volume can be created using different password. Of course I hope I will never be in such a situation where an adversary forces me to reveal my password.

Traveller mode is a way to run TrueCrypt without having to install it on the operating system under which it is running. For example you can have a TypeCrypt USB drive and using it on any computer.

Chinese support

You can download language pack to update interface to diffenent languages. Simplified Chinese pack is available.

After downloading the language pack, unzip and copy the xml file to the install folder (eg. C:Program FilesTrueCrypt ).

Where to get it?

• TrueCrypt is at http://www.truecrypt.org/
• Current version: 4.3
• Function: File encryption and security utility

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Regular readers will know that I keep a keen eye on security and protection on private data. Previously I covered using KeePass to store password (of course the best would be to keep everything in the head), using Tor and Privoxy for anonymous browsing and setting up a VPN to share data using Hamachi.

In this post (and the next), I want to share some tools that will secure your data on your harddisk.

Eraser is an open source security tool which allows you to completely remove sensitive data from your hard drive by overwriting it several times with carefully selected patterns.

Why do you want to do this?

The reason lies in the fact that when you delete a file, Windows does not really remove the file from the harddisk. It just removes the reference of the file (not the actual content). The file content still remains on the disk until another file is written over it. Even after file is written over it, it might still be possible for a sophisticated person to recover the data by studying the magnetic patterns on the disk surface.

Nevermind if you do not quite understand the last paragraph*. Just remember if you need to securely remove a file so that no one else can recover it, you need a tool like Eraser.

Tools like Eraser goes by a few description. They are sometime referred to as file shredder, disk wiper, destructive delete, etc.

Basically there are 2 main functions that you want to use them for

1. To delete (shred) an existing file or disk so that it is no longer recoverable.
2. To clean (wipe) your empty harddisk space so that old, deleted data cannot be recovered.

Eraser can do both.

Using Eraser

After installing, erasing a file is just a simple right-click on the file and choose Erase.

You can leave the Options as its default and go ahead and click Yes.

A status box will appear showing the erasing. Depending on your file size this may take a while.

Wiping Empty Disk Space

To wipe empty/unused disk space, right-click on a disk drive.

Follow the same confirmation as the file shredding. If you have a large disk, this will take a long time.

*Useful reference:

• File wiping on Wikipedia
• Why a normal delete is not sufficient

Chinese support

Ufortunately it seems like the UI does not support other languages.

Where to get it?

• Eraser is at http://www.heidi.ie/eraser/
• Current version: 5.82
• Function: File Shedder (Eraser)

Related Post:

• KeePass 1.06 release
• Are you still using FTP? Beware
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One solution is to get Hamachi installed on both PCs.

Hamachi is not open source but the free version is very usable and I have used it on occassions between office, home and client’s location. (Hamachi had just been acquired by LogMeIn Inc in August 2006, it seems like the free version will continue to be available.)

There are a number of solutions available to achieve remote connection, even Windows XP comes with Remote Desktop. But what makes Hamachi stands out is the ease of use. Once installed, you just have to follow the few guided steps to get it up and running.

If you have ever tried connecting to remote computers with softwares like VNC, PCAnywhere or even a VPN you will find that the setup is often a big hassle, especially for non-technical users.

Here are a few problematic scenarios I can think of,

• you are behind a firewall in a client’s office
• you office LAN is behind a router (or wireless router)
• you do not know the IP of the remote computer
• you need some to run a host/server at the remote computer to listen to your connection

Hamachi’s concept, however, makes it easy to deal with all these sceanrios. There are no ports to be opened or configured and no need to find the remote IP. (For the technically inclined, find out how it works)

The steps are simple (and Hamachi comes with a very intuitive Quick Guide that explains each step.)

1. Download and run the install. (Assuming you are using the Windows version.)
2. If this is your first installation, you need to create a Network.
   A Network is basically like a workgroup with members of the same Network can share resource.
3. Once you have installed Hamachi on other computers, add them to the same Network

Once Hamachi is running this is what you see.

How to connect to shared folders?

If your office LAN has a few computer sharing files, you can install Hamachi with all computers in the same Hamachi network.

Right-click on any member of the network and click browse. You will be able to browse the file like in Windows’ Network Neighbourhood.

One draw back of the free version Hamachi is that the program cannot be run as a service. What this means is that a Windows XP user is required to log on and run Hamachi. In another word, connecting to an unattended computer may fail if the computer does not auto-logon like in the case of multiple user or password protected computer.

Fear not! Go to the Hamachi forum, a source of many useful information, you will find solution to this and many more advanced usage.

In the meantime, try Hamachi, I’m sure it will bring a new level of connectedness in your business and work.

What I like about Hamachi?

• very easy to use, even for non-technical users
• no messy configuration
• file and print sharing across multiple LAN and locations
• other network protocols (like SSH, FTP, HTTP, VNC) can go through it transparently
• encrypted

My wishlist for Hamachi

• official support for FreeBSD

Chinese support

The Simplified Chinese version of Hamachi can downloaded from the download page (click on “Click here for more languages”).

In the English version, Hamachi is able to support Chinese characters in the Nickname and Network name. So there is no problem using Hamachi in a mixed English-Chinese environment.

Where to get it?

• Hamachi is at http://www.hamachi.cc/
• Current version: 1.0.1.1
• Function: VPN, LAN over the Internet

Related Post:

• Remote Control with UltraVNC

I was shocked!

You see, in the last 7-8 years I have not use FTP on my servers. Even on the local office server I refuse to allow FTP to be installed. For file transfer I just use SFTP (Filezilla supports this).

Are you still using FTP, you might want to read the following and discover why it is time to take note

• Details of how FTP works and security.
• FTP Security Considerations

The traditional FTP protocol is highly insecure: it sends passwords in the clear. For this reason FTP has been recognized as one of the largest remaining security liabilities in most UNIX systems. As of 2006 FTP still remains one of the Internet’s most popular file upload mechanisms.

Another security risk lies not with FTP itself but with the widespread use of wireless internet connection.

With wireless, your FTP password travelling in clear over the air can be easily captured. You may be surprised that wireless attack is actually very easy. The kid next door may just be looking at your wireless traffic now.

So, if you are using FTP on your hosting server and at work, ask why. Security file transfer like SFTP, SCP, FTP over SSL are widely available. Perhaps it is time to ask if the hosting provider support them or move on to a more knowledgable hosting provider.

At this point I am still talking to the vendor to see how the FTP requirement can be relaxed or best removed.

Reference:

• Wireless Security Recommendations for Rutgers
• Wireless security on Wikipedia

Related Post:

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