Encryption software that allows for multiple passwords with varying actions?

I don't know of any such software that can do exactly what you want to. However, TrueCrypt allows you to create a so called hidden volume;

It may happen that you are forced by somebody to reveal the password to an encrypted volume. There are many situations where you cannot refuse to reveal the password (for example, due to extortion). Using a so-called hidden volume allows you to solve such situations without revealing the password to your volume.

The principle is that a TrueCrypt volume is created within another TrueCrypt volume (within the free space on the volume). Even when the outer volume is mounted, it should be impossible to prove whether there is a hidden volume within it or not*, because free space on any TrueCrypt volume is always filled with random data when the volume is created** and no part of the (dismounted) hidden volume can be distinguished from random data. Note that TrueCrypt does not modify the file system (information about free space, etc.) within the outer volume in any way.

Basically, you are required to set 2 passwords where only one will unlock and decrypt the entire volume while the other only decrypts a part. The (still) encrypted part will be hidden and it's not possible to detect it as a hidden partition since the volume space is filled with seemingly arbitrary data.

A little illustration (retrieved from the same TrueCrypt page as mentioned above):

enter image description here

BloodPhilia

Posted 2012-03-07T15:37:48.903

Reputation: 27 374

Yes I'd known of this, however there is always this http://xkcd.com/538/ =).

– John – 2012-03-07T15:57:57.420

@johnthexiii what exactly is the point you're trying to make? Hidden encryption is nearly always more secure than deleting the files since deleted files are (usually) pretty easily recovered by experts... – BloodPhilia – 2012-03-07T15:59:43.487

The point is once I've given password number two I never want to be able to get to the files again no matter how much physical abuse is given, even after 7 passes I'll take my chances with the experts. – John – 2012-03-07T16:06:06.270

1@johnthexiii Then no, I don't think such software exists... Again, would like to make clear that erasing the files would NOT guarantee that recovery is impossible. – BloodPhilia – 2012-03-07T16:07:16.613

It would be feasible to place a script on the (nonhidden) volume, that --when the nonhidden volume is booted-- overwrites the on-disk part of the key for the hidden volume. On the other hand, you'd have a bot of trouble explaining the existence of the script afterwards. Also, I wouldn't like to lead your testing efforts. – Eroen – 2012-03-07T16:24:04.817

@Eroen Again, erasing leaves traces and (almost always) salvageable data... – BloodPhilia – 2012-03-07T16:25:08.993

@Eroen I could just have the script erase itself however testing, as you pointed out, would be unpleasant. – John – 2012-03-07T16:30:17.913

Question does not specify the system needs to be deniable ;), and as long as you know there are no images floating around (in which case you're screwed anyway), remanence is (according to wikipedia) a smaller issue than what some have claimed.

– Eroen – 2012-03-07T16:35:12.743

@johnthexiii Yes, in principle, but filesystems are know to be tricky. – Eroen – 2012-03-07T16:37:22.400

1@Johnthexiii - You don't seem to accept the advice being given. – Ramhound – 2012-03-07T17:08:33.780

Wow. You think entering in password 2 and the computer starts erasing the files makes you safe? Your life is forfeited. If it was law enforcement, they can now hunt down the process that deleted the files. Now they can charge you with destroying evidence. . . It sounds like a lose/lose. – surfasb – 2012-03-07T19:27:31.130

@surfasb maybe destroying evidence would be preferable to whatever you would be charged with if information was recovered from your hdd. – John – 2012-03-09T15:04:43.563

Encryption software that allows for multiple passwords with varying actions?

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