Festplattenverschlüsselung mit TrueCrypt

Installing TrueCrypt

TrueCrypt can be installed on Windows, Linux, or Mac OSX. The installation files are available here: http://www.truecrypt.org/downloads The following three sections give complete details on how to install TrueCrypt for each of these Operating Systems, starting with Ubuntu and Debian.

Installing on Ubuntu/Debian

TrueCrypt is not available in the standard Ubuntu repositories. This means you cannot use the Ubuntu Software Center or apt-get (a command line method for installing software on Ubuntu) to install it. Instead you must first visit the TrueCrypt downloads page. You will see a drop-down menu under the heading Linux.

Festplattenverschlüsselung mit TrueCrypt

From the ‘(Select a package)’ drop down menu you can choose from four options:

Festplattenverschlüsselung mit TrueCrypt

Choosing the correct package to download

This is a little technical -the console version is the one you choose if you are either very technical and don’t like Graphical User Interfaces or you wish to run this on a machine that you have only a terminal (command line or ‘shell’) access to (like a remote server for example).  Assuming you are running this in your laptop its best to choose the easy ‘standard’ option -this will give you a nice user interface to use. From these two options you need to choose the one most suitable for the architecture of your machine. Don’t know what this meansfi Well, it basically comes down to the type of hardware (processor) running on your computer, the options are 32-bit or 64-bit. Unfortunately Ubuntu does not make it easy for you to find this information if you don’t already know it. You need to open a ‘terminal’ from the Applications->Accessories menu and type the following, followed by the [enter] key

uname -a

The output will be something like Linux bigsy 2.6.32-30-generic #59-Ubuntu SMP Tue Mar 1 21:30:46 UTC 2011 x86 64 GNU/Linux. In this instance you can see the architecture is 64-bit (x86 64). In this example I would choose the ‘Standard -64-bit (x64)’ option. If you see i686 somewhere in the output of the uname command then you would choose the other standard option to download. Once selected press the ‘download’ button and save the file to somewhere on your computer. So the installation process is still not over. The file you downloaded is a compressed file (to make downloading it faster) and you need to first de-compress the file before you install it. Fortunately Ubuntu makes this easy -simply browse to the file on your computer and right click on it and choose ‘Extract Here’.

Festplattenverschlüsselung mit TrueCrypt

Right click and ‘extract here’ You will see a new file appear next to the compressed file:

Festplattenverschlüsselung mit TrueCrypt

The extracted file

Nearly done! Now right click on the new file and choose ‘open’:

Festplattenverschlüsselung mit TrueCrypt

Right click and ‘open’ If all is well you will see a window open like this:

Festplattenverschlüsselung mit TrueCrypt

Window opens to confirm you want to ‘run’ the file. Choose ‘run’ and you see the following: Now we are getting somewhere. . . press ‘Install TrueCrypt’. You will be displayed a user agreement. At the bottom press ‘I accept and agree to be bound by the license terms’ (sounds serious). You will then be shown another info screen telling you how to uninstall TrueCrypt. Press ‘OK’ then you will be asked for your password to install software on your computer. Enter your password and then you will finally see a screen like this:

Believe it or now your are done. . . TrueCrypt is installed and you can access it from the Applications->accessories menu. . . close the setup window. Now proceed to the chapter

Festplattenverschlüsselung mit TrueCrypt

Truecrypt installer starts. . .

Festplattenverschlüsselung mit TrueCrypt

Truecrypt install finished. . . ‘press Enter to exit’

on Using TrueCrypt.

Installing on OSX

  1. To install TrueCrypt on OSX first visit the download page (http://www.truecrypt.org/downloads)
    and press the download button under the OSX section.
  2. Download this to your computer find the .dmg file and open it to access the installation package.
  3. Open the installation package, and click through the dialogues.
  4. Choose the standard installation. You can choose to do a customized installation and deselect FUSE, but why would youfi You need it!
  5. After the installation finishes you can find the program in your ‘Applications’ folder.

Festplattenverschlüsselung mit TrueCrypt

Download button

Festplattenverschlüsselung mit TrueCrypt

Open the .dmg file

Festplattenverschlüsselung mit TrueCrypt

Click through the dialogues

Festplattenverschlüsselung mit TrueCrypt

Choose standard installation

Festplattenverschlüsselung mit TrueCrypt

Truecrypt launcher now in Applications

Installing on Windows

To install TrueCrypt on Windows first visit the download page (http://www.truecrypt.org/downloads)
and press the download button under the Windows section.

Download this to your computer and then double click on the file. You will see a license agreement.

Click on ‘I accept and agree to be bound by the license terms’ and then click ‘Accept’.

Leave the above screen with the defaults and press ‘Next >’ and you will be taken to the Setup Options window:

You can leave this with the defaults. If you want to set up TrueCrypt just for yourself then consider not selecting the ‘Install for all users’. However if you are installing this on your own machine and no one else uses the computer then this is not necessary. You may also wish to consider installing TrueCrypt in a folder other than the default. In which case click ‘Browse’ and choose another location. When you are done click ‘Install’ and the process will proceed:

When the installation is complete you will get a verification popup that it was successful. Close this window and click ‘Finish’ and all is done. Now proceed to the chapter on Using TrueCrypt. The following are step-by-step instructions on how to create, mount, and use a TrueCrypt volume.

Creating a TrueCrypt Container

  1. Install TrueCrypt. Then launch TrueCrypt by

• double-clicking the file TrueCrypt.exe in Windows • opening Applications->Accessories->TrueCrypt in Ubuntu • on MacOSX open it by clicking Go > Applications. Find TrueCrypt in the

Applications folder and double click on it.

  1. When the main TrueCrypt window appears. Click Create Volume.
  2. You should see the TrueCrypt Volume Creation Wizard window appear on screen.

Festplattenverschlüsselung mit TrueCrypt

Where do you want to create the TrueCrypt volumefi You need to choose now. This can be in a file, which is also called a container, in a partition or drive. The following steps will take you through the first option creating a TrueCrypt volume within a file.

You can just click Next, as the option is selected by default,

Festplattenverschlüsselung mit TrueCrypt

Next you need to choose whether to create a standard or hidden TrueCrypt volume. We will walk you through the former option and create a standard TrueCrypt volume.

Festplattenverschlüsselung mit TrueCrypt

You can just click Next, as the option is selected by default. Now you have to specify where to have the TrueCrypt volume (file container) created. Note that a TrueCrypt container behaves like any normal file. It can be moved or deleted as any normal file. Click Select File.

The standard file selector will now appear on screen (the TrueCrypt Volume Creation Wizard remains open in the background). You need to browse to the folder that the file should be created in and then type into the ‘name’ field the name for the file you wish to create.

Festplattenverschlüsselung mit TrueCrypt

Festplattenverschlüsselung mit TrueCrypt

We will create our TrueCrypt volume in the folder ‘adam/true’ and the filename of the volume (container) will be ‘myencryptedfile’. You may, of course, choose any other filename and location you like (for example, on a USB stick). Note that the file ‘myencryptedfile’ does not exist yet -TrueCrypt will create it. Press ‘Save’ when you are ready. The file selector window should close.

IMPORTANT: Note that TrueCrypt will not encrypt any existing files. If an existing file is selected in this step, it will be overwritten and replaced by the newly created volume (the contents of the existing file will be lost). You will be able to encrypt existing files later on by moving them to the TrueCrypt volume that we are creating now.

  1. In the Volume Creation Wizard window (which was previously running in the background), click Next.
  2. Here you can choose an encryption algorithm and a hash algorithm for the volume.

Festplattenverschlüsselung mit TrueCrypt

The TrueCrypt manual suggests that if you are not sure what to select here, you can use the default settings and click Next (for more information about each setting have a look at the TrueCrypt documentation website).

  1. Now choose the size of your container. You should be fine with 1 megabyte but for this example we will enter ‘20’ into the available field.
    You may, of course, specify a different size. After you type the desired size in the input field, click Next.
  2. This step is really important, choosing a password. The information displayed in the Wizard window about what is considered a good password, should be read carefully.

 

Festplattenverschlüsselung mit TrueCrypt
Festplattenverschlüsselung mit TrueCrypt

Choose a strong password, type it in the first input field. Then re-type it in the input field below the first one.

When you are done click Next.

  1. Now you must choose the format of your partition (this step may not be available for you under windows or OSX). If using Ubuntu you can choose a Linux file type or FAT (Windows) for simplicity leave it at the default.

Festplattenverschlüsselung mit TrueCrypt

Then press Next.

  1. Next TrueCrypt tries to generate random information to help encrypt your container. For 30 seconds move your mouse as randomly as possible within the Volume Creation Wizard window. Move the mouse as much as possible for up to a minute. This significantly increases security by increasing the cryptographic strength of the encryption keys. security). Move your mouse around until you are bored.

Then Click Format.

TrueCrypt will now create a file in the folder you selected with the name you chose. This file will be a TrueCrypt container, containing the encrypted TrueCrypt volume. This may take some time depending on the size of the volume. When it finishes this should appear:

Click OK to close the dialog box.

  1. Well done! You’ve just successfully created a TrueCrypt volume (file container).

In the TrueCrypt Volume Creation Wizard window, click Exit.
Festplattenverschlüsselung mit TrueCrypt

Festplattenverschlüsselung mit TrueCrypt

 

  1. Open up TrueCrypt again.
  2. Make sure one of the ‘Slots’ is chosen (it doesn’t matter which -you can leave at the default first item in the list). Click Select File.
  3. In the file selector, browse to the container file (which we created earlier) and select it.
    Click Open (in the file selector window). The file selector window should disappear.
  4. In the main TrueCrypt window, click Mount. Password prompt dialog window should appear.
  5. Type the password in the password input field.
  6. Click OK in the password prompt window.

Festplattenverschlüsselung mit TrueCrypt

The standard file selector window should appear.

Festplattenverschlüsselung mit TrueCrypt

Festplattenverschlüsselung mit TrueCrypt

Festplattenverschlüsselung mit TrueCrypt

Festplattenverschlüsselung mit TrueCrypt

Installing TrueCrypt

TrueCrypt can be installed on Windows, Linux, or Mac OSX. The installation files are
available here: http://www.truecrypt.org/downloads

The following three sections give complete details on how to install TrueCrypt for each of these Operating Systems, starting with Ubuntu and Debian.

Installing on Ubuntu/Debian

TrueCrypt is not available in the standard Ubuntu repositories. This means you cannot use the Ubuntu Software Center or apt-get (a command line method for installing software on Ubuntu) to install it. Instead you must first visit the TrueCrypt downloads
page (http://www.truecrypt.org/downloads).

You will see a drop-down menu under the heading Linux.

Festplattenverschlüsselung mit TrueCrypt

Dropdown menu on the download page
From the ‘(Select a package)’ drop down menu you can choose from four options:

Festplattenverschlüsselung mit TrueCrypt

Figure 11.2: Choosing the correct package to download

This is a little technical -the console version is the one you choose if you are either very technical and don’t like Graphical User Interfaces or you wish to run this on a machine that you have only a terminal (command line or ‘shell’) access to (like a remote server for example).

Assuming you are running this in your laptop its best to choose the easy ‘standard’ option -this will give you a nice user interface to use. From these two options you need to choose the one most suitable for the architecture of your machine. Don’t know what this meansfi Well, it basically comes down to the type of hardware (processor) running on your computer, the options are 32-bit or 64-bit. Unfortunately Ubuntu does not make it easy for you to find this information if you don’t already know it. You need to open a ‘terminal’ from the Applications->Accessories menu and type the following, followed by the [enter] key

uname -a

The output will be something like Linux bigsy 2.6.32-30-generic #59-Ubuntu SMP Tue Mar 1 21:30:46 UTC 2011 x86 64 GNU/Linux. In this instance you can see the architecture is 64-bit (x86 64). In this example I would choose the ‘Standard -64-bit (x64)’ option. If you see i686 somewhere in the output of the uname command then you would choose the other standard option to download.

Once selected press the ‘download’ button and save the file to somewhere on your computer.

So the installation process is still not over. The file you downloaded is a compressed file (to make downloading it faster) and you need to first de-compress the file before you install it. Fortunately Ubuntu makes this easy -simply browse to the file on your computer and right click on it and choose ‘Extract Here’.

Festplattenverschlüsselung mit TrueCrypt

Right click and ‘extract here’ You will see a new file appear next to the compressed file:

Festplattenverschlüsselung mit TrueCrypt

The extracted file

Nearly done! Now right click on the new file and choose ‘open’:

Festplattenverschlüsselung mit TrueCrypt

Right click and ‘open’ If all is well you will see a window open like this:

Festplattenverschlüsselung mit TrueCrypt

Window opens to confirm you want to ‘run’ the file

Choose ‘run’ and you see the following:

Now we are getting somewhere. . . press ‘Install TrueCrypt’. You will be displayed a user agreement. At the bottom press ‘I accept and agree to be bound by the license terms’ (sounds serious). You will then be shown another info screen telling you how to uninstall TrueCrypt. Press ‘OK’ then you will be asked for your password to install software on your computer. Enter your password and then you will finally see a screen like this:

Believe it or now your are done. . . TrueCrypt is installed and you can access it from the Applications->accessories menu. . . close the setup window. Now proceed to the chapter

Installing TrueCrypt

Festplattenverschlüsselung mit TrueCrypt

Truecrypt installer starts. . .

Festplattenverschlüsselung mit TrueCrypt

Truecrypt install finished. . . ‘press Enter to exit’

Installing on OSX

  1. To install TrueCrypt on OSX first visit the download page (http://www.truecrypt.org/downloads)
    and press the download button under the OSX section.
  2. Download this to your computer find the .dmg file and open it to access the installation package.
  3. Open the installation package, and click through the dialogues.
  4. Choose the standard installation. You can choose to do a customized installation and deselect FUSE, but why would youfi You need it!
  5. After the installation finishes you can find the program in your ‘Applications’ folder.

Festplattenverschlüsselung mit TrueCrypt

Download button

Festplattenverschlüsselung mit TrueCrypt

Open the .dmg file

Festplattenverschlüsselung mit TrueCrypt

Click through the dialogues

Festplattenverschlüsselung mit TrueCrypt

Choose standard installation

Festplattenverschlüsselung mit TrueCrypt

Truecrypt launcher now in Applications

Installing on Windows

To install TrueCrypt on Windows first visit the download page (http://www.truecrypt.org/downloads)
and press the download button under the Windows section.

Download this to your computer and then double click on the file. You will see a license agreement.

Click on ‘I accept and agree to be bound by the license terms’ and then click ‘Accept’.

Leave the above screen with the defaults and press ‘Next >’ and you will be taken to the Setup Options window:

You can leave this with the defaults. If you want to set up TrueCrypt just for yourself then consider not selecting the ‘Install for all users’. However if you are installing this on your own machine and no one else uses the computer then this is not necessary. You may also wish to consider installing TrueCrypt in a folder other than the default. In which case click ‘Browse’ and choose another location. When you are done click ‘Install’ and the process will proceed:

When the installation is complete you will get a verification popup that it was successful. Close this window and click ‘Finish’ and all is done. Now proceed to the chapter on Using TrueCrypt. The following are step-by-step instructions on how to create, mount, and use a TrueCrypt volume.

Creating a TrueCrypt Container

  1. Install TrueCrypt. Then launch TrueCrypt by

• double-clicking the file TrueCrypt.exe in Windows • opening Applications->Accessories->TrueCrypt in Ubuntu • on MacOSX open it by clicking Go > Applications. Find TrueCrypt in the

Applications folder and double click on it.

  1. When the main TrueCrypt window appears. Click Create Volume.
  2. You should see the TrueCrypt Volume Creation Wizard window appear on screen.

Festplattenverschlüsselung mit TrueCrypt

Where do you want to create the TrueCrypt volumefi You need to choose now. This can be in a file, which is also called a container, in a partition or drive. The following steps will take you through the first option creating a TrueCrypt volume within a file. You can just click Next, as the option is selected by default,

Festplattenverschlüsselung mit TrueCrypt

  1. Next you need to choose whether to create a standard or hidden TrueCrypt volume. We will walk you through the former option and create a standard TrueCrypt volume.

Festplattenverschlüsselung mit TrueCrypt

You can just click Next, as the option is selected by default.

  1. Now you have to specify where to have the TrueCrypt volume (file container) created. Note that a TrueCrypt container behaves like any normal file. It can be moved or deleted as any normal file.

Click Select File.

The standard file selector will now appear on screen (the TrueCrypt Volume Creation Wizard remains open in the background). You need to browse to the folder that the file should be created in and then type into the ‘name’ field the name for the file you wish to create.

 

Festplattenverschlüsselung mit TrueCrypt

 

Festplattenverschlüsselung mit TrueCrypt

 

We will create our TrueCrypt volume in the folder ‘adam/true’ and the filename of the volume (container) will be ‘myencryptedfile’. You may, of course, choose any other filename and location you like (for example, on a USB stick). Note that the file ‘myencryptedfile’ does not exist yet -TrueCrypt will create it. Press ‘Save’ when you are ready. The file selector window should close.

IMPORTANT: Note that TrueCrypt will not encrypt any existing files. If an existing file is selected in this step, it will be overwritten and replaced by the newly created volume (the contents of the existing file will be lost). You will be able to encrypt existing files later on by moving them to the TrueCrypt volume that we are creating now.

  1. In the Volume Creation Wizard window (which was previously running in the background), click Next.
  2. Here you can choose an encryption algorithm and a hash algorithm for the volume.

Festplattenverschlüsselung mit TrueCrypt

The TrueCrypt manual suggests that if you are not sure what to select here, you can use the default settings and click Next (for more information about each setting have a look at the TrueCrypt documentation website).

  1. Now choose the size of your container. You should be fine with 1 megabyte but for this example we will enter ‘20’ into the available field. You may, of course, specify a difierent size. After you type the desired size in the input field, click Next.
  2. This step is really important, choosing a password. The information displayed in the Wizard window about what is considered a good password, should be read carefully.

Festplattenverschlüsselung mit TrueCrypt

Festplattenverschlüsselung mit TrueCrypt

Choose a strong password, type it in the first input field. Then re-type it in the input field below the first one.
When you are done click Next.

  1. Now you must choose the format of your partition (this step may not be available for you under windows or OSX). If using Ubuntu you can choose a Linux file type or FAT (Windows) for simplicity leave it at the default.

Festplattenverschlüsselung mit TrueCrypt

Then press Next.

  1. Next TrueCrypt tries to generate random information to help encrypt your container. For 30 seconds move your mouse as randomly as possible within the Volume Creation Wizard window. Move the mouse as much as possible for up to a minute. This significantly increases security by increasing the cryptographic strength of the encryption keys. security). Move your mouse around until you are bored.

Then Click Format.

TrueCrypt will now create a file in the folder you selected with the name you chose. This file will be a TrueCrypt container, containing the encrypted TrueCrypt volume. This may take some time depending on the size of the volume. When it finishes this should appear:

Click OK to close the dialog box.

  1. Well done! You’ve just successfully created a TrueCrypt volume (file container).

In the TrueCrypt Volume Creation Wizard window, click Exit.

Festplattenverschlüsselung mit TrueCrypt

Festplattenverschlüsselung mit TrueCrypt

Mounting the Encrypted Volume

1. Open up TrueCrypt again.

2. Make sure one of the ‘Slots’ is chosen (it doesn’t matter which -you can leave at the default first item in the list). Click Select File.

3. In the file selector, browse to the container file (which we created earlier) and select it.

Click Open (in the file selector window).
The file selector window should disappear.

4. In the main TrueCrypt window, click Mount. Password prompt dialog window should appear.

5. Type the password in the password input field.

6. Click OK in the password prompt window.

Festplattenverschlüsselung mit TrueCrypt
The standard selector window should appear.

Festplattenverschlüsselung mit TrueCrypt

 

Festplattenverschlüsselung mit TrueCrypt

 

Festplattenverschlüsselung mit TrueCrypt

Festplattenverschlüsselung mit TrueCrypt

TrueCrypt will now attempt to mount the volume. If the password is correct, the volume will be mounted.

If the password is incorrect (for example, if you typed it incorrectly), TrueCrypt will notify you and you will need to repeat the previous step (type the password again and click OK).

  1. We have just successfully mounted the container as a virtual disk 1. The container will appear on your Desktop or you will see it in your file browser.

What does this meanfi

The disk that you have just created is completely encrypted and behaves like a real disk. Saving (moving, copying, etc) files to this disk will allow you to encrypt files on the fly.

You’ll be able to open a file which is stored on a TrueCrypt volume, which will automatically be decrypted to RAM while it is being read, and you won’t need to enter your password each time. You’ll only need to enter this when your mounting the volume.

Remember to dismount!

To do this right click on the drive and select unmount. This will automatically happen when you turn off your computer but will not happen if you just put the computer on sleep.

Setting up a hidden volume

A TrueCrypt hidden volume exists within the free space of a typical TrueCrypt volume. Given then the ‘outer volume’ is accessed it is (almost) impossible to determine if there is a hidden volume within it. This is because TrueCrypt always fills the empty space of an encrypted volume with random data. So a hidden volume looks the same as an empty TrueCrypt volume.

To create and use a hidden volume you need two passwords -one each for the outer and inner (hidden) volumes. When you mount (open) the volume you can use either password and that will determine which of the two is opened. If you want to open just the hidden volume you use one password, and if you want to access just the non-hidden encrypted volume you use the other password.

To create a hidden volume open TrueCrypt and press the ‘Create Volume’ button:

Festplattenverschlüsselung mit TrueCrypt

The options for half of this process are almost the same as for setting up a standard TrueCrypt volume and then the process continues for setting up the hidden volume but lets go through the entire process step by step anyway. In the screen shown below you just want to stay with the default setting ‘Create an encrypted file container’:

Press ‘Next >’ and continue to the next screen.

In the above screen you want to be sure that you choose the second option ‘Hidden TrueCrypt Volume’. Select this and click on ‘Next >’ you will then be asked to choose the location and name of the TrueCrypt outer volume.

Click ‘Select File. . . ’ and browse to a location for a new TrueCrypt volume. We will use the name ‘myencryptedfile’ in this example. Its the same name as we used in the

Festplattenverschlüsselung mit TrueCrypt

last example so be aware that if you have just followed those instructions you must now create a new volume with a new name.

Festplattenverschlüsselung mit TrueCrypt

Browse to the directory where you want to put the outer volume and enter the name of the volume in the field named ‘Name’ as in the example above. When you are satisfied all is well click on ‘Save’. The file browser will close and you return to the Wizard. Click ‘Next >’. Here you are presented with some very technical choices. Don’t worry about them. Leave them at the defaults and click ‘Next >’. The next screen asks you to determine the size of the outer volume. Note that when you do this the maximum inner ‘hidden’ volume size is determined by TrueCrypt. This maximum size will of course be smaller that the size you are setting on this screen. If you are not sure what the ratio of outer volume size to inner (hidden) volume size is then go through the process now as a ‘dummy’ run -you can always trash the encrypted volume and start again (no harm done).

So choose the size of the outer volume, I will choose 20MB as shown below:

Festplattenverschlüsselung mit TrueCrypt

You cannot set the outer volume size to be larger than the amount of free space you have available on your disk. TrueCrypt tells you the maximum possible size in bold letters so create a volume size smaller than that. Then click ‘Next >’ and you will be taken to a screen asking you to set a password for the outer (not the hidden, this comes later) volume.

Enter a password that is strong (see the chapter on creating good passwords) and press ‘Next >’. Next TrueCrypt wants you to help it create the random data it will fill the volume up with. So wave your mouse around, browse the web, and do whatever you want for as long as you can. When you feel TrueCrypt should be happy then press ‘Format’. You will see a progress bar zip by and then you will be presented with the next screen:

You can open the outer volume if you like but for this chapter we will skip that and go ahead to create the hidden volume. Press ‘Next >’ and TrueCrypt will work out how the maximum possible size of the hidden volume.

When you see the above screen just press ‘Next >’. Now you must choose the encryption type for the hidden volume. Leave it at the defaults and press ‘Next >’.

Now you will be asked to choose the size of the hidden volume.

I have set (as you see above) the maximum size as 10MB. When you have set your maximum size press ‘Next >’ and you will be prompted to create a password for the hidden volume.

When creating the password for the hidden volume make sure you make it substantially different fro the password for the outer volume. If someone really does access your

Festplattenverschlüsselung mit TrueCrypt

drive and finds out the password for the outer volume they might try variations on this password to see if there is also a hidden volume. So make sure the two passwords are not alike.

Enter your password in the two fields and press ‘Next >’.

Leave this window at the defaults and press ‘Next >’ and you will be presented with the same screen you have seen before to generate random data for TrueCrypt. When you are happy click ‘Format’ and you should see the following :

The TrueCrypt manual it is referring to is not this manual. They mean this manual: http://www.truecrypt.org/docs/

Click ‘OK’ and keep and exit TrueCrypt. You can now mount the volume as noted in the previous chapter.

Festplattenverschlüsselung mit TrueCrypt