Full Disk Encryption Hard For Law Enforcement To Crack 575
If you'd rather keep your data private, take heart: disk encryption is a lot harder to break than techno-thriller movies and TV shows make it out to be, to the chagrin of some branches of law enforcement.
MrSeb writes with word of a paper titled "The growing impact of full disk encryption on digital forensics" [abstract here to paywalled article] that illustrates just how difficult it is. According to the paper, co-authored by a member of US-CERT, "[T]here are three main problems with full disk encryption (FDE): First, evidence-gathering goons can turn off the computer (for transportation) without realizing it's encrypted, and thus can't get back at the data (unless the arrestee gives up his password, which he doesn't have to do); second, if the analysis team doesn't know that the disk is encrypted, it can waste hours trying to read something that's ultimately unreadable; and finally, in the case of hardware-level disk encryption, tampering with the device can trigger self-destruction of the data. The paper does go on to suggest some ways to ameliorate these issues, but ultimately the researchers aren't hopeful: 'Research is needed to develop new techniques and technology for breaking or bypassing full disk encryption.'"
Re:I have my disk (at least partially) encrypted (Score:3, Interesting)
Re:I have my disk (at least partially) encrypted (Score:5, Interesting)
RAM can hold a copy of the last data held for a good 5 seconds if warm and up to +20mins of frozen,
so it could be chilled/frozen using compressed air, removed and placed into a reader that dumps the ram memory to disk.
Re:Giving up passwords (Score:5, Interesting)
(unless the arrestee gives up his password, which he doesn't have to do);
In the UK he does [theregister.co.uk]. And people have been punished [theregister.co.uk] for not handing it over.
Unfortunately for everybody, really, the potential 5-year RIPA sentence for refusing to disclose a key is crazy draconian as a threat to induce Joe Public to open every Turing-complete device in his entire life to the cops(after what is, no doubt, a impeccable judicial review); but it is substantially less scary than the sentence you might get for various serious crimes that the key might be hiding, along with any incentive provided by your criminal colleagues in favor of loyalty to the organization...
Re:Giving up passwords (Score:3, Interesting)
if you are 'innocent' why do you encrypt your data in the first place?
If you are innocent, why do you post as AC?
Deniable encryption only works in theory (Score:5, Interesting)
Countries that respect and protect a right to free speech would not outlaw such a system, but unfortunately such countries are few and far between. Deniable encryption encryption works in theory, but in practice the existence of non-deniable encryption makes it hard for people to claim that they are innocent users of a deniable encryption system. While there are innocent uses of such a system (perhaps your business secrets are so valuable that being tortured for them is not beyond the realm of possibility) they are few and far between; deniable encryption is tool for protecting your data from a government, and for all their talk about China and Iran, most western governments are not interested in having citizens who can secure their communications and data from police investigations.
Re:Giving up passwords (Score:5, Interesting)
isn't the UK part of the same EU ?
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=COM:2006:0174:FIN:EN:HTML
2.4. Privilege against self-incrimination
The presumption of innocence includes the privilege against self-incrimination which is made up of the right of silence and not to be compelled to produce inculpating evidence. The maxim nemo tenetur prodere seipsum , (“no person is to be compelled to accuse himself”) applies. The accused may refuse to answer questions and to produce evidence. The ECtHR[24] held that, although not specifically mentioned in the ECHR, the privilege against self-incrimination is a generally recognised international standard which lies “at the heart of the notion of a fair procedure”. It protects the accused against improper compulsion by the authorities, thus reducing the risk of miscarriages of justice and embodying the equality of arms principle. The prosecution must prove its case without resort to evidence obtained through coercion or oppression. Security and public order cannot justify the suppression of these rights[25].They are linked rights, any compulsion to produce incriminating evidence being an infringement of the right of silence. The State infringed an accused’s right of silence when it sought to compel him to produce bank statements to customs investigators[26]. Coercion to co-operate with the authorities in the pre-trial process may infringe the privilege against self-incrimination and jeopardise the fairness of any subsequent hearing.
Re:I wish this was the case in the UK (Score:5, Interesting)
It takes a pretty exceptional human to actually remember a useful crypto key
Not really. How hard is to remember a paragraph from your favorite novel or lyrics from a popular song. It's even better if you *mis-remember* the quote/lyrics so that you're the only one who would come up with the result even if someone tried to brute force the key by scanning all your books and listening to all your music.
Perhaps something like:
While the music played you worked by candle light, those San Francisco nights - you were the best in town, Just by chance you crossed the diamond with the pearl, you turned it on the world, that's when you turned the world around
Or maybe:
I was alone I took a ride, I didn't know what I would find there. Another road where maybe I could see another kind of mind there. ooh and I suddenly see you, ooh did I tell you I need you? Every single day of my life.
Try and brute force those keys. Using punctuation makes it even harder. And these are the first verses to well known songs. Use the third verse of an obscure song (one you don't like would be even better). The music makes it much easier to remember and just about anyone can remember songs/lyrics.
Some people just have zero imagination. Sigh!
Re:Giving up passwords (Score:4, Interesting)
My SSD is encrypted with AES in hardware. As I understand it, you only have to send one ATA command to the disk to tell it to generate a new key and thereby make the existing data unreadable to anyone.
Personally I'd prefer a 'wipe key' button on my laptop to a cyanide pill in my teeth.
Getting the oppertunity to send that one key is tricky if you are in handcuffs.
Better to have a key you hand over after a suitable number of threats which does the new key generation. You can always blame the cops for being technological cavemen and damaging your computer. He who touches it last acquires all blame.
Re:Giving up passwords (Score:3, Interesting)
Because my photography is mine, and a stolen hard drive means anybody can freely access years of copyrighted work that's only available online with watermarks, and I make my living from selling my current photography and back library. Because my writing is similarly mine. Because I have confidential information about well over fifteen hundred clients on my HD, none of which I'd like to fall into a competitor's hands. Because I have pornography of myself and my partner on there that neither of us want anyone else to have access to.
All of which is innocent, all of which nobody but those I wish to will get access to.
Re:I wish this was the case in the UK (Score:5, Interesting)
Unfortunately, it's not difficult to look at the OS for evidence that the hidden partition exists. Even if they don't realize its a truecrypt hidden volume, they might start asking for usb drives that you haven't turned over.
www.schneier.com/paper-truecrypt-dfs.pdf
I always thought you could do one better (Score:5, Interesting)
Encrypted drives do not, obviously, use the password to decode the files. They use the password to decode a key and use that to encode the files.
So I always thought it would be interested to have a computer that, on startup, wipes that part of the disk with 0s, sticking a copy somewhere else on the drive. (Which is not a security risk, because the other parts of the drives are, obviously, encrypted with that key, and you can't open box with a box cutter inside it.)
And during safe shutdown, it puts it back. Or have a program you have to run to put it back, then shutdown.
For safety purposes, you give a copy of the key to someone else for safekeeping. Bonus points if they're out of the country.
Then you leave your computer on, and the screen locked, at all times. Bonus points if you rig it to an alarm where if someone breaks in, it cuts the power. (Also have it do the same if someone inserts firewire or USB while the screen is locked.)
Now it doesn't matter how much you're ordered to comply with the police. They come in, cut the power to your computer, make a disk image...and you'll tell them the damn password all they want, but you are rather at a loss as to how they think that will work, considering the part of the drive with the key stored is has apparently been filled with 0s. (You'll need a lawyer able to explain that what they are asking cannot work.)
Now, like I said, you can lie and pretend you don't know what's going on...or you can wait until they get a court order to have you decrypt, and then tell them what's going on. By which point your friend has hopefully already destroyed the key.
And the joke is, even if you explain everything that happened, this is entirely legal. You have not destroyed any evidence, because the key was already missing from the unencrypted part of the drive when the warrant showed up. (Unlike some of the automated 'destroy data' traps that people try to come up with.) And you have cooperated fully, you literally cannot get to the data. And your friend didn't destroy evidence, because the search warrant was for your stuff, he can delete of his own files he wants until he is told otherwise.
Ultimate in planted evidence... (Score:5, Interesting)
You want to do someone in, and have access to their computer, a USB program that creates an encrypted partition would be enough to do one in. Proving one's innocence would probably be near impossible.
Re:Deniable encryption only works in theory (Score:4, Interesting)
Steganography software does not need to be on your computer, it can be on a web service. Also, encryption itself is not outlawed in most places (this would make everyone a criminal who visits a https site for example), you just have to hand over the password if asked. Now hidden drives can be found by scanning the hard drive, but steganography can't.
Re:I always thought you could do one better (Score:5, Interesting)
Now it doesn't matter how much you're ordered to comply with the police. They come in, cut the power to your computer...
When law enforcement officers confiscate a computer, they usually (in the US at least) try to transport the computer without powering it down. Standard procedure is to plug a portable generator into the wall outlet powering the computer, unscrew the outlet, and take the whole apparatus (including wall outlet, generator, and computer) to the forensics lab, without interrupting power to the computer. If all the jacks in an outlet are in use, they will unscrew the wall outlet and splice the generator's power cables into the outlet.
The article and summary do mention situations where computers are powered down for transportation. These are exceptions. They are not the norm.
Re:Here's a clue LEO guys... (Score:4, Interesting)
Indeed. Always remember what Cardinal Richelieu said,
"Give me six lines written by the most honorable of men, and I will find an excuse in them to hang him."
The powerful have always arranged the laws so that troublesome people can be easily suppressed at will. It's basic government 101; control the population through fear of arbitrary arrest and proscription. Don't fool yourself into thinking that this practice doesn't continue into the present day in "free" nations.
Re:More research? (Score:2, Interesting)
FDE actually is more of a benefit for police and LEOs than it causes them problems.
Lets view two realistic worse-case scenarios (with FDE being breakable versus not), removing the ticking time-bomb scenario from the equation for now:
1: A prosecutor has to let a hardened child molestor go free, because of how good FDE is.
2: A list of police informant contacts on a stolen machine gets stolen, the fence who finds the laptop is able to decrypt it. Next thing the local police know, all their good contacts now have extra sunlights in their craniums forcibly installed, as well as a good chunk of their family members.
If given a balance, LEOs, companies, and government benefit far more from FDE than they would lose. They have *far* more to lose in secrets than to gain in prosecuting the one diaper sniper they get with a backdoor.
Oh... putting in backdoors in FDE algorithms is expert footshooting -- just like Clipper/Skipjack, the bad guys WILL find them, and will use those to wreak large amounts of havoc.
Of course, when the bad guys know that FDE is backdoored, there is one other method they can go to -- storing data remotely and just using their machine as a client, say with a Citrix terminal server. Come a bust, the laptop is clean, the virtual desktop is clean, and there is no evidence of where anything is.
In fact, I worked at a company this paranoid ages ago. All their PCs booted from CD-ROMs, and they remoted into a terminal server via their VPN in another country for all their work.
So, the bad guys can easily just move their data to countries hostile to the US, add some type of system with a duress capability so if they type in a slighly different password, the remote site deletes data, or just blocks access, and there is nothing that can be done.