Creating Double-Bottom Cryptocontainers
If you have decided to set up comprehensive security for your devices and are reading our course for this purpose, you should have already transitioned to using cryptocontainers. All the information you regularly work with on your computer should be organized into cryptocontainers – this is a fundamental rule. But surely you have information that you would like to hide especially securely, as there are many methods of hacking cryptocontainers in the arsenal of malicious actors. There are two ways to address this task: the first is masking cryptocontainers, the second is using double-bottom cryptocontainers. The essence of a double-bottom cryptocontainer is extremely simple: when entering one password, you get one piece of information, and when entering another – a different one. With software and hardware tools, it is impossible to prove the existence of a double bottom, but if you are asked for access and cannot refuse, you can provide access to the "public" content, and no one will know about the existence of the double bottom and its contents (at the end of the material, I will show with a real-life example that this is a myth). In preparing this material, I read a common opinion that the hidden area of a cryptocontainer can be calculated by clearing the open part and checking the free space for writing. If there is a hidden area, it will take up space, and it will become obvious that the cryptocontainer has a double bottom. In reality, this is a myth. The presence of a hidden cryptocontainer will not affect the main one at all, even if it occupies a significant portion of its size. If you write a file to the cryptocontainer that exceeds the size of the free space in the cryptocontainer, it will be written over the hidden part without revealing its existence. Double-bottom cryptocontainers are created the same way on TrueCrypt and VeraCrypt, the same on all operating systems. We will demonstrate using VeraCrypt on macOS.