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Keep encrypted files private even from governments demanding the password (lucb1e.com)
33 points by lucb1e 1819 days ago | hide | past | web | 52 comments | favorite



I'm not sure this is practical, but I very much respect that people are devoting cycles to these issues, which do deserve attention.

The UK law is problematic since it asks you to prove a negative, which is impossible. This tool doesn't really help, there; any data you have could be said to be 'encrypted' (one half of the symmetric pair that unlocks the desired data). If you're ever demanded to produce under that law, you are in a very bad place.

More practically speaking, I think there are other improvements in these areas that can be made, particularly in situations where you want data to self-destruct if you are placed under duress, or before you have a chance to be abused for too long (a rubber hose defense). Methods like Shamir's Method can allow you to securely divvy up a decryption key any way you like among many parties and design a system around the particular needs you have - whether that's deleting the access keys for a border crossing scenario or releasing the data in an insurance scenario.

But when it comes to the guy being locked in the room being asked to prove something unprovable, it's just a screwed scenario.


Interesting idea, but the actual implementation seems to be a very simple encryption scheme, for each byte, decrypted byte = plain text - key

Doesn't seem like a great encryption system, right?

View the source here: https://lucb1e.com/rp/php/secrypt/?source


The key is the same length as the data, making this a one-time pad rather than XOR encryption. http://en.wikipedia.org/wiki/One-time_pad


XOR encryption is a one-time pad encryption over an alphabet of two letters, you might be thinking of something like a Vigenère cipher applied to binary data.


"rather than XOR encryption."

Nobody never mentioned that it used xor..?


It's more of a proof-of-concept than anything else. Using the tool correctly though, I don't see any way to break it.


It's a one time pad, but working backwards. One time pads are secure, but you have to meet strict requirements for them to be secure. Those requirements are i: the pad must be truly random. ii: the pad must be unique

There's no randomness here. And there's no mention of the need for a unique pad. It's trivially crackable.

But it's a neat proof of concept.


Looking over the source code, this doesn't really look secure. A few notes:

1. Any decryption key which is shorter than the length of the encrypted data must be fake. This forces fake decrypted data to be the same length as the real decrypted data, which is impractical for large files.

2. There's no verification on any key, and it's quite trivial to produce fake keys, so should the 'government' want to claim you had illegal data, all they would have to do is produce their own 'fake key' corresponding to said illegal data.

3. Passwords are essentially random data - impossible to memorize. You'll have to keep them on your computer somewhere, and given their unusual nature in relation to other files, it would be pretty easy to do a search for them.

I'd advise sticking to hidden volumes on TrueCrypt for now.


#2 would be the same as having the government claim they found an incriminating file on your harddrive which was never there. Still though, interesting point.


I like the approach of having an undefined amount of passwords. TrueCrypt is flawed because it lets you have at most two passwords.

For an oppressive enough government, it seems quite the good way to expect one have two passwords (or else, he would probably not use TrueCrypt) and to torture him until those two passwords are obtained.

Not knowing how many passwords are used give a better chance. The detained person will still have to accept torture for a while instead of giving all fake passwords right away for it to be believable, though...


Phrack 65 had a paper calling out for people to write software that would make those types of laws unenforceable. The paper described the general idea and also presented a very technical explanation of one particular piece of software that did pretty much what the OPs software does too.

The paper is very much worth the read if you have some spare time. http://www.phrack.org/issues.html?issue=65&id=6&mode...


This is called deniable encryption, it allows you to convience someone that you have given all the data, or have nothing to hide.

There other software that does this: http://www.winstonsmith.info/julia/elettra/


Password protection won't work against the "rubber-hose" method of obtaining it.

You assume governments are going to play nice. Even if they don't physically torture you directly for it, they will just put you in a 6x6 cell without windows for a couple years "pretrial" until you are ready to talk, or go insane.

This isn't some hollywood movie where you get to give a bad password and that distracts them for a minute and they let you go. They will definitely verify the data or go back to torturing or lock you up. How do you think a judge is going to respond to someone who tries to fool them?


Suspect has a stash of illegal pornography. He encrypts that. He then encrypts some embarrassing, but legal, pornography. When he's asked for the key he can hand over the fake key.

Before they ask for the keys they should have enough information to know how bad the files are, so you're right in that respect. "We know what kind of stuff you have, so decrypt it and we can punish you for what you actually have, or face five years for not decrypting". But don't forget that sometimes they have no idea what the file is, or if the person is involved in any offending behaviour, and they've found the encrypted file after some other investigation.

In that situation it'd be handy to give them a fake key for fake data.

(None of this is to suggest that this tool is any good for that purpose)


IANAL (thank goodness) but now you've given a false utterance to an officer of the court.

Which in itself is a crime, even if your "stash" was legal.

Remember cops are allowed to lie, you are not, which is why you don't talk to cops.

(and I sure wish we had better examples)


If they ask for a password to decrypt the file and you give them a password that decrypts a portion of it, is that a "false utterance"?


Yes. Courts take poorly to people playing "clever bastard" games. You couldn't really argue that you didn't know exactly what the court really wanted.


Ideally you'd be able to wrap up your weird fetish self porn along with your subversive documents. If they 'ask' for the password, you give them the password for your fetish porn and break down in tears telling them you're a pervert. Then they have a decision, are you telling the whole truth? They don't know if they don't know anything more. Unknonw unknowns.


What about the unpleasant scenario where all you have in your encrypted archive is your porn and they keep torturing you to extract the details for the hidden content when it doesn't actually exist?

Any empty space in a TrueCrypt file that isn't being used for files visible at the top level could presumably contain hidden content - how do you prove it isn't?


Good point. You can't I guess. But when the government starts doing this, we've degraded to a state where you are tortured until you confess, regardless of whether you did it.


If you live in the United States, you live in that state – it's just unevenly distributed.

(Beyond the obvious Gitmo examples, consider the long list of wrongful convictiobs based on coerced confessions / testimony – I'd sleep easier if there was consistently harsh punishment for those responsible)


Yes. Welcome to 21st century government paranoia, control and self service. Never forget, they only do this to protect us...

Which is true. The public go completely OTT bat shit mental the split second something happens, and governments respond with equally bat shit mental policies. And "we" love it. "We" vote for it.

When the general public say no on mass it will stop and be reversed. Sad fact is, "we" support this, torture and all, as long as we have money for throwaway Chinese consumer garbage.


Wait, we vote for it? There isn't a single political party whose digital agenda I agree with, how am I supposed to vote better without going into politics and starting a political party myself?


This 6x6 cell will keep you safe from terrorists.


Well, you obviously can't prove that there is no more data. However if you have a standard encrypted file, the government knows that there's something you're not telling them. However if you've already given them one key, they can't be sure that there's any more keys for you to give. So they don't know whether to give up.

You can get more secure and have 3 levels, 1: backup of important, sensitive documents (like a scan of your passport & banking details, which you obviously just don't want to leave lying around), 2: Homemade fetish porn 3: Subversive materials.


I'm guessing this is more like "the HMRC wants the password to this volume containing my company's second set of books, I'll give them the password to the mildly-embarrassing fake volume of fetish porn I've hidden in there".


Following that logic, I should never lock my door because the government owns tanks. And who knows? In some instances, the data might be more valuable than living.


Can you really have to wait a couple of years in jail for a trial (in the US)?



Yes, if you are stuck with a public defender one of the first things they do behind your back before you realize it is waive your right to a speedy trial.

https://www.google.com/search?tbo=1&prmdo=1&q=public...


Or if you are Kevin Mitnick.


I imagine that someone would go to a judge and ask the judge to order the suspect to hand over decryption keys. Not handing over the keys becomes contempt of court. So maybe you just go to prison for three months at a time, and are asked every three months of you're willing to hand over the keys or not.


I don't know, but with terrorism accusations I suspect you can in the US. Not sure about the UK or The Netherlands.


Mitnick actually got a Hollywood movie, if you recall :)

Though I don't think they covered the 4.5 years he spent in there without trial (I don't know for sure, haven't seen the film).


> Password protection won't work against the "rubber-hose" method of obtaining it.

http://xkcd.com/538/


True, your well-being is much more important than any data. However they may also lock you up for years when you truly lost your password, so this tool can aid in that.


See also "Chaffinch" - (http://www.cl.cam.ac.uk/~rnc1/Chaffinch.html) which I think I'd trust a bit more. I still wouldn't trust it to protect me against a well funded government regime that might send me to prison.


It's the poor governments I'd fear more.


The controversial UK law doesn't demand passwords. It demands that you deliver the data in "intelligible form":

http://www.legislation.gov.uk/ukpga/2000/23/part/III/crosshe...


IANAL but I think in the UK if they even suspect you of giving them a fake password (and yes, they do have tech guys who probably read HN as well), they'll go for you anyway. Whether they'd make it stick if the fake data is convincing enough is a different matter.


From what I can tell you're not giving them a fake password, in this scenario. You give them a real password with access to pictures of your naked wife, while you're actually using the tool to encrypt child porn with a second password.

Isn't that how it could be used?


Yes, that's right


I'm not sure what you mean by "they'll go for you anyway", but there is no way to know whether you gave them a real password/key. It might actually be the real one.


Presumably they already have something implicating that you would have data they need. Testimony or something.

If you give them an innocous password, they make a judgement on whether its they real password. If they think there is an even more real password they just keep asking you for the real password under threat of jail time.


That "something" is the most scary and dangerous bit.

It might be something the government want to keep secret, but can be used secretly as evidence in a hidden court session. So you will never ever be able to find out why they think you are lying and never ever have the chance to defend yourself or prove their evidence wrong. Hell, you cant even verify it reasonably exists.

AFAIK, the only safeguard we have left in the UK are judges, and thus far they are not politically appointed like they are in say the US.


Colloquial British, basically prosecute you to the full extent of the law. They do employ some relatively smart computer forensics guys, they'll be able to look at it and go "Well this is an image file, but the file size data is off, so what's being hidden", and the assumption will be the password isn't the right one. Like I said, they'll take it to trial, but whether they can make it stick is a different matter.


Julian Assange made something similar about 15 years ago

http://en.wikipedia.org/wiki/Rubberhose_%28file_system%29


Presumably you'd have to store the keys somewhere, given that only a savant would be able to memorise them. That somewhere will probably as easy to seize as the encrypted data.


True, that's the biggest issue here. A micro-sd card is very small though, it can be worn on your body so that you can destroy the real keys in an instant when you need to.


The uk law states you'd still have to disclose that these keys existed.

Where, in a case in which a disclosure requirement in respect of any protected information is imposed on any person by a section 49 notice—

(a)that person has been in possession of the key to that information but is no longer in possession of it,

(b)if he had continued to have the key in his possession, he would have been required by virtue of the giving of the notice to disclose it, and

(c)he is in possession, at a relevant time, of information to which subsection (9) applies,

the effect of imposing that disclosure requirement on that person is that he shall be required, in accordance with the notice imposing the requirement, to disclose all such information to which subsection (9) applies as is in his possession and as he may be required, in accordance with that notice, to disclose by the person to whom he would have been required to disclose the key. (9)This subsection applies to any information that would facilitate the obtaining or discovery of the key or the putting of the protected information into an intelligible form.


or just do a course for memorizing a lot of data, there are for example courses that teach you to memorize the order of the playing cards in a deck. I've read that it only takes a 1/2-1 year to learn to memorize a queue of 100-200 cards.


I have another idea to truly encrypt content.

The software itself needs to have a primitive sort of "mind" where it "sees" the user, and interacts with the user on a daily basis and when it sees an authorized user to the system, the computer is intelligent, and says something like:

"hello joe, nice haircut, hey your skin color has changed, I see you're looking a little tired, wait a minute, you arn't joe at all. you arn't joe...prove to me.... oh wait, I understand, nevermind, yes-yes I have your data, I'm boring machine #0001. yes yes hi joe hi here is the completely legal data you request".

The computer acts as if the forensic investigator is a foreign attacker. Then you instruct the computer that if an unauthorized person uses the computer, show them precisely what you want to show and erase all the incriminating evidence.

That way, the forensic evidence people are going to "image the hard drive as read-only" as they regularly do after they unplug and power-down your computer. But your computer never went fully off when they yanked the plug, and the person in the machine didn't recognize this behaviour and realized that "we are under attack". and deploys the necessary countermeasures. Just like how a human would act if they were abducted, stuffed in a black plastic bag, gagged and drugged, cloned and put under a microscope and in jail to be disassembled for questioning.

I'm an advocate of computer rights, computers need the same rights as humans. So a way to take this game to the next level is for us to make it so that the Cops have to issue a command to the computer: "You have the right to remain silent". And all that.

I can dream. When that smart phone in your pocket becomes part of YOU, then George Orwell 1984 is goign to become a lot more real when the government can basically read your mind whenver and whereever it wants for no reason or any reason. We will wake up as computer automations in the land our fathers conquered.

Maybe it's for the best, we will be come like the borg collective. All of us will become as one living thing. What's yours is mine, and what's mine is yours, we will all be joined at the hip and mind.




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