Re: English 19-year-old jailed for refusal to disclose decryption key
On Thu, 7 Oct 2010, Nicolas Williams wrote:
If decryption results in plaintext much shorter than the ciphertext -much
shorter than can be explained by the presence of a MAC- then it'd be fair to
assume that you're pulling this "trick".
Not to argue with your overall point re: crypto not protecting citizens from
their states, but I disagree with the above in the case of truecrypt, which is
what was being discussed.
I have many unencrypted drives (or partitions) that are only partially
full. It's quite plausible that an encrypted drive would not be very
full. ("I thought I might need more space later." or "well, I had all
of this space...")
Moreover, possession of software that can do "double encryption" could be
considered probable cause that your files are likely to be encrypted with it.
There's a lot of software I use daily which has features I never touch. I use
the alpine MUA, but I never have it fetch mail from a POP server, I don't use
message scroing, etc. Maybe the suspect selected truecrypt because it works on
all of linux, MacOS and Windows, unlike so many other such tools. And is free,
unlike BestCrypt. There are many plausible reasons for selecting that tool
that have nothing to do with the double encryption feature.
-- Sam
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Re: English 19-year-old jailed for refusal to disclose decryption key
On Oct 7, 2010, at 1:10 PM, Bernie Cosell wrote: a 19-year-old just got a 16-month jail sentence for his refusal to disclose the password that would have allowed investigators to see what was on his hard drive. What about http://www.truecrypt.org/docs/?s=plausible-deniability Could this be used? Sure. And the technology used would have no effect on the standard ... used in court: I think you're not getting the trick here: with truecrypt's plausible deniability hack you *CAN* give them the password and they *CAN* decrypt the file [or filesystem]. BUT: it is a double encryption setup. If you use one password only some of it gets decrypted, if you use the other password all of it is decrypted. There's no way to tell if you used the first password that you didn't decrypt everything. So in theory you could hide the nasty stuff behind the second passsword, a ton of innocent stuff behind the first password and just give them the first password when asked. In practice, I dunno if it really works or will really let you slide by. You're thinking too much about the technology. The court demands a company turn over its books. The company denies it keeps any books. Sure - massive fines, possible jail sentences for the principals. Alternatively, the company turns over fake books. There is evidence that the books are fake - they show the company only did 2000 transactions last year, but somehow the company paid a staff of 200 to take phone calls last year. Or the books don't show any payments for things that we see sitting in the warehouse. Or maybe there are just purely statistical anomalies: The variation in income from week to week is way out of the range shown by other businesses. Or there's just someone who swears that these are not the books he's seen in the past. Same outcome for the company. Maybe the high-tech cheats let you get away with stuff; maybe they don't. Then again, maybe the fake paper books let you get away with stuff, and maybe they don't. Technology lets you play some games more easily, but it's not magic pixie dust that immunizes you from reality. -- Jerry - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
Re: English 19-year-old jailed for refusal to disclose decryption key
On 10/07/2010 12:10 PM, Bernie Cosell wrote: There's no way to tell if you used the first password that you didn't decrypt everything. Is there a way to prove that you did? If yes, your jailers may say "We know you have more self-incriminating evidence there. Your imprisonment will continue until you prove that you've given us everything." If no, your jailers may say "We know you have more self-incriminating evidence there. Your imprisonment will continue until you prove that you've given us everything." Get it? So in theory you could hide the nasty stuff behind the second passsword, a ton of innocent stuff behind the first password and just give them the first password when asked. If the encrypted file is large, and disk file fragmentation patterns, timestamps, etc. suggest it has grown through reallocation, the 4 KB grocery list you decrypt out of it is not going to convince anyone. On the other hand, if you produce a sufficient amount of relatively incompressable image, video, or encrypted data from it, you may be able to convince them that you've decrypted it all. - Marsh - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
Re: English 19-year-old jailed for refusal to disclose decryption key
On Thu, Oct 07, 2010 at 01:10:12PM -0400, Bernie Cosell wrote: > I think you're not getting the trick here: with truecrypt's plausible > deniability hack you *CAN* give them the password and they *CAN* decrypt > the file [or filesystem]. BUT: it is a double encryption setup. If you > use one password only some of it gets decrypted, if you use the other > password all of it is decrypted. There's no way to tell if you used the > first password that you didn't decrypt everything. So in theory you > could hide the nasty stuff behind the second passsword, a ton of innocent > stuff behind the first password and just give them the first password > when asked. In practice, I dunno if it really works or will really let > you slide by. There is no trick, not really. If decryption results in plaintext much shorter than the ciphertext -much shorter than can be explained by the presence of a MAC- then it'd be fair to assume that you're pulling this "trick". The law could easily deal with this. Plausible deniability with respect to crypto technology used is not really any different than plausible deniability with respect to knowledge of actual keys. Moreover, possession of software that can do "double encryption" could be considered probable cause that your files are likely to be encrypted with it. Repeat after me: cryptography cannot protect citizens from their states. Nico -- - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
Re: English 19-year-old jailed for refusal to disclose decryption key
On 7 Oct 2010 at 12:05, Jerry Leichter wrote: > On Oct 7, 2010, at 4:14 AM, Christoph Gruber wrote: > >>> a 19-year-old just got a 16-month jail sentence for his refusal to > >>> disclose the password that would have allowed investigators to see > >>> what was on his hard drive. > >> > > What about http://www.truecrypt.org/docs/?s=plausible-deniability > > Could this be used? > Sure. And the technology used would have no effect on the standard ... used in court: I think you're not getting the trick here: with truecrypt's plausible deniability hack you *CAN* give them the password and they *CAN* decrypt the file [or filesystem]. BUT: it is a double encryption setup. If you use one password only some of it gets decrypted, if you use the other password all of it is decrypted. There's no way to tell if you used the first password that you didn't decrypt everything. So in theory you could hide the nasty stuff behind the second passsword, a ton of innocent stuff behind the first password and just give them the first password when asked. In practice, I dunno if it really works or will really let you slide by. /Bernie\ -- Bernie Cosell Fantasy Farm Fibers mailto:ber...@fantasyfarm.com Pearisburg, VA --> Too many people, too few sheep <-- - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
Re: English 19-year-old jailed for refusal to disclose decryption key
On Oct 7, 2010, at 4:14 AM, Christoph Gruber wrote: >>> a 19-year-old just got a 16-month jail sentence for his refusal to >>> disclose the password that would have allowed investigators to see >>> what was on his hard drive. >> > What about http://www.truecrypt.org/docs/?s=plausible-deniability > Could this be used? Sure. And the technology used would have no effect on the standard used in court: Is there sufficient convincing evidence that there's data there to decrypt (e.g., you used the system in the last day to send a message based on the kind of information sought)? If so, decrypt or go to jail. "Beyond a reasonable doubt" isn't the standard for everything, and even of it were, it's as understood by a judge or jury, not a logician. -- Jerry - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
Re: English 19-year-old jailed for refusal to disclose decryption key
Am 06.10.2010 um 22:57 schrieb Marsh Ray: > On 10/06/2010 01:57 PM, Ray Dillinger wrote: >> a 19-year-old just got a 16-month jail sentence for his refusal to >> disclose the password that would have allowed investigators to see >> what was on his hard drive. > > I am thankful to not be an English "subject". What about http://www.truecrypt.org/docs/?s=plausible-deniability Could this be used? -- Christoph Gruber "If privacy is outlawed, only outlaws will have privacy." Phil Zimmermann - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
Re: English 19-year-old jailed for refusal to disclose decryption key
On Thu, Oct 7, 2010 at 5:57 AM, Ray Dillinger wrote: > a 19-year-old just got a 16-month jail sentence for his refusal to > disclose the password that would have allowed investigators to see > what was on his hard drive. > > I suppose that, if the authorities could not read his stuff > without the key, it may mean that the software he was using may > have had no links weaker than the encryption itself -- and that > is extraordinarily unusual - an encouraging sign of progress in > the field, if of mixed value in the current case. > > Really serious data recovery tools can get data that's been > erased and overwritten several times (secure deletion being quite > unexpectedly difficult), so if it's ever been in your filesystem > unencrypted, it's usually available to well-funded investigators > without recourse to the key. I find it astonishing that they > would actually need his key to get it. Interesting. It's interesting to think about the possibilities some sort of homomorphic cryptosystem would offer here. I.e. it would be arguably useful (from one point of view) if they were able to search the data for specific items, and failing finding items of those types, *then* the fallback is this sentence, otherwise it seems like a pretty trivial way out for anyone wishing to hide bad activity. > Rampant speculation: do you suppose he was using a solid-state > drive instead of a magnetic-media hard disk? > > http://www.bbc.co.uk/news/uk-england-11479831 > > Bear -- silky http://dnoondt.wordpress.com/ "Every morning when I wake up, I experience an exquisite joy — the joy of being this signature." - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
Re: English 19-year-old jailed for refusal to disclose decryption key
On 10/06/2010 03:55 PM, Joss Wright wrote: The .. Regulation of Investigatory Powers Act of 2000 (RIPA), .. allows for a maximum sentence of two years for refusing a request that encrypted data be "put into an intelligible form". Five years, if a national security or child indecency case. http://www.legislation.gov.uk/ukpga/2000/23/section/53 Arshad Noor StrongAuth, Inc. - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
Re: English 19-year-old jailed for refusal to disclose decryption key
On 06/10/10 19:57, Ray Dillinger wrote: > a 19-year-old just got a 16-month jail sentence for his refusal to > disclose the password that would have allowed investigators to see > what was on his hard drive. Just to correct this: the sentence was 16 weeks, not 16 months. The legislation in question is the Regulation of Investigatory Powers Act of 2000 (RIPA), part III of which has been in force in the UK since 2007. This allows for a maximum sentence of two years for refusing a request that encrypted data be "put into an intelligible form". Reference here: http://wiki.openrightsgroup.org/wiki/RIP_Act_Part_III Joss - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
Re: English 19-year-old jailed for refusal to disclose decryption key
On 6 October 2010 11:57, Ray Dillinger wrote: > a 19-year-old just got a 16-month jail sentence for his refusal to > disclose the password that would have allowed investigators to see > what was on his hard drive. 16 weeks, says the article. - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
Re: English 19-year-old jailed for refusal to disclose decryption key
On 10/06/2010 01:57 PM, Ray Dillinger wrote: a 19-year-old just got a 16-month jail sentence for his refusal to disclose the password that would have allowed investigators to see what was on his hard drive. I am thankful to not be an English "subject". I suppose that, if the authorities could not read his stuff without the key, it may mean that the software he was using may have had no links weaker than the encryption itself Or that the authorities didn't want to reveal their capability to break it. Or that they wanted to make an example out of him. Or... -- and that is extraordinarily unusual - an encouraging sign of progress in the field, if of mixed value in the current case. Really serious data recovery tools can get data that's been erased and overwritten several times Really? Who makes these tools? Where do they make that claim? Wouldn't drive manufacturers have heard about this? What would they do once they realized that drives had this extra data storage capacity sitting unused? I see this idea repeated enough that people accept it as true, but no one ever has a published account of one existing or having been used. > (secure deletion being quite unexpectedly difficult) Sure, but mainly because of stuff that doesn't get overwritten (i.e., drive firmware remaps sectors which then retain mostly valid data) not because atomic microscopy is available. , so if it's ever been in your filesystem unencrypted, it's usually available to well-funded investigators without recourse to the key. I find it astonishing that they would actually need his key to get it. What makes you think these investigators were well-funded? Or they wouldn't prefer to spend that money on other things? Or that they necessarily would have asked the jailers to release the teen because they'd been successful in decrypting it. Perhaps their plan was to simply imprison him until he confesses? Rampant speculation: do you suppose he was using a solid-state drive instead of a magnetic-media hard disk? SSDs retain info too. Due to the wear leveling algorithms they're quite systematic about minimizing overwrite. But I doubt any of that is an issue in this case. - Marsh - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
