- cypherpunks-legacy - lists.cpunks.org

Re: art-stego
by jrochkin＠cs.oberlin.edu 17 Dec '03

17 Dec '03

At 7:18 PM 03/04/96, Jim Miller wrote: >The recent discussion "Chaff in the Channel" got me thinking about an >alternative to hiding random bit streams in picture files. The goal of >steganography, as I see it, is to provide plausible deniability. The >problem with hiding bit streams is that you can never be sure if the >opponent has developed an analysis technique to prove a particular file >contains a suspicious bit pattern. The way I understand steganography working, you would use it to hide mathematically random data. Mainly encrypted data. Like a PGP encrypted message, but with all PGP headers and other non-random data removed. Photos are a great medium for steganography, since they already contain noise of various sorts. So a good steganography algorithm (which I understand exists) merely changes the values of the noise so that it now encodes your (random) message. So there's no way to look for "suspicious bit patterns", and even if you use a publically available stego program to encode your data, and they use the same program to unstego your data, all they wind up with is a random bit stream, and they have no way of telling if it's just noise in the picture or your PGP encrypted message. So you already have all the plausible deniability you need, and I don't see how Jim's method is an improvement. Of course, if they have methods to crack PGP encrypted messages, and they use it on yours even without being sure it is an encyrypted message, and eventually wind up with a clear text message, well, then they've got your clear text message. And you are unlikely to be able to claim that it's just a coincidence they managed to extract several paragraphs about laundering money in bermuda from the GIF or orca the killer whale. But this is true of any stego method--if they can manage to get a cleartext message out of it, plausible deniability is unlikely to get you far. Am I wrong about any of the above?

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Re: art-stego
by JonWienke＠aol.com 17 Dec '03

17 Dec '03

.WAV files are potentially a good place to store stego information. With a 16-bit file, as many as 8 of the least significant bits in each sample can be replaced with encrypted info without making the file sound too wierd (depending on the natural background noise of the recording). If you make one of those "waves on the beach" relaxation things, you might be able to get away with even more. Another thing--just a wild idea--test the randomness of encrypted data by storing it in an 8-bit mono .WAV (your choice of sample rates) file and listening to it. Any correlations or patterns in the data should show up in the playback as hums, clicks, squeals, or something. It may even be possible to determine the algorithm by the sound patterns--a sort of "audio cryptanalysis." Has anyone tried this? Are there any .WAV stego programs out there? Jonathan Wienke

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Re: Looking for code to run an encrypted mailing list
by Matts Kallioniemi 17 Dec '03

17 Dec '03

At 23:17 1996-03-04 -0800, John Pettitt wrote: >The overal intent was to have a message go from one list member to all >others with a) a signature to provide strong attribution and a measure of >non repudiation b) low probability of interception c) only the gateway has >to have all the public keys. You could avoid alot of encryption by setting up a key for the list and giving both keys (secret and public) to all the list members. To write to the list, you encrypt with the lists public key. Everybody reading the list can decrypt with the secret key. Pros: No hacking of majordomo. You can use any mailing list software. The key and clear text message is never available to a robot, making it harder to compromise security. Cons: When somebody is removed from the list you have to change the key, encrypt the new secret key with everybodys public keys and distribute it. For a big dynamic list where people unsubscribe daily this could be a major headache. But for small or static lists it shouldn't be much of a problem. <matts(a)pi.se>

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Re: Truelly Random Numbers
by tcmay＠got.net 17 Dec '03

17 Dec '03

At 1:55 PM 3/5/96, Tim Fulbright wrote: >Now I, a lurker for two months, am truelly confused! L. Deitweiler must be >right. Surely one of you cyperpunk fellows could hack together a dongle with >some kind of AD converter and buffer ram to gather a Truelly Random Bitstream >off the environment every couple of milliseconds easier than this raindrop >scheme or recording the fan, you're haviung me on!. Let's go back fifty years >and get a vacuum tube to fitfully flicker? I who know next to nothing about >electronics suspect there is surely enough noise present in electornic devices >to gather a random bitstream that you could chop anywya you needed? Anyway, y Just because someone floats their idea does not mean it is the "list consensus"! That "raindrops falling on my plate" idea was something I deleted as soon as I saw that it wasn't a joke with a nice punchline. (Not all flaky ideas get rebutted...though, as a matter of fact, I did see several quick rebuttals of the raindrop idea as being impractical, too low a data rate, etc.) Johnson noise in semiconductors and alpha particle noise have indeed been discussed _many_ times. Check the archives, or my Cyphernomicon FAQ. --Tim May Boycott "Big Brother Inside" software! We got computers, we're tapping phone lines, we know that that ain't allowed. ---------:---------:---------:---------:---------:---------:---------:---- Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay(a)got.net 408-728-0152 | anonymous networks, digital pseudonyms, zero W.A.S.T.E.: Corralitos, CA | knowledge, reputations, information markets, Higher Power: 2^756839 - 1 | black markets, collapse of governments. "National borders aren't even speed bumps on the information superhighway."

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Bidzos on CNBC, discussing Leahy's Bill
by tcmay＠got.net 17 Dec '03

17 Dec '03

I'm watching Jim Bidzos being interviewed on CNBC...mainly about Leahy's bill (he's in favor of it)....(One of the benefits of having CNBC business news on all the time while I'm here online.) He thinks it's a good bill, good for U.S. industry, good for California...says some of the language in the bill still provides for "key escrow" of some sort (I think he means the criminal use of crypto provisions....). He still thinks customers absolutely do not want any other parties to hold their keys ("You don't give copies of the keys to your front door or your filing cabinets to the government now, so why should you just because the medium changes from filing cabinets to computer form."--paraphrased). No further word on RSADSI going public, though. (I'm constantly surprised that this hasn't happened, what will all the later-comers going public, and the general hyping of "Internet security" (not that it isn't important, just that it seems that any company with these magic words in its name or prospectus zooms through the roof on IPO). --Tim Boycott "Big Brother Inside" software! We got computers, we're tapping phone lines, we know that that ain't allowed. ---------:---------:---------:---------:---------:---------:---------:---- Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay(a)got.net 408-728-0152 | anonymous networks, digital pseudonyms, zero W.A.S.T.E.: Corralitos, CA | knowledge, reputations, information markets, Higher Power: 2^756839 - 1 | black markets, collapse of governments. "National borders aren't even speed bumps on the information superhighway."

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Re: Truelly Random Numbers
by Bill Stewart 17 Dec '03

17 Dec '03

>At 10:11 AM 3/3/96 -0500, Gary Howland wrote: >>Surely the process of counting up until you get a prime means >>that the chances of getting certain primes are greater than >>others (eg. 17 is more likely than 19) ? At 11:07 AM 3/3/96 -0800, jamesd(a)echeque.com wrote: >In order to use this information, one would need to determine >the number of primes in the vicinity of a potential prime factor. >This costs more than actually checking for the factor, hence is >not useful. The discussion has been about probability of collisions, rather than usable exploits - they're still rare enough that it's a birthday-problem issue. While you're more likely to pick a specific prime with a large gap before it than one with a small gap before it, there are a lot more small gaps than large ones, assuming that primes are roughly uniformly distributed within any given range (which is roughly true) and that therefore the gaps are geometrically distributed. I worked an example for random 384-bit primes, which you'd use to generate 768-bit RSA keys. The density of primes is approximately 1/ln384 = 1/266 = 1/meanlength. The unweighted quartile gap lengths are 77, 186, and 372. The weighted quartiles for the gaps are 255, 447, and 720 ; these correspond to unweighted cdfs of 61%, 81%, and 93%. So, yes, it's a bit skewed (and enough that I'd rather not work the birthday problem math, which is far easier with uniforms :-) But it's probably not skewed enough to affect the number of primes required for a collision to occur by more than a factor of 100 or so, and collisions in RSA keys require collisions in both primes.

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"Political Life in Cyberspace" forum, NYC, 3/12/96
by dmandl＠panix.com 17 Dec '03

17 Dec '03

For those of you in the NYC area, I'm presenting a forum next week on "Political Life in Cyberspace" (not my title). I'm going to skip the boring net-boosterism and talk mainly about several bleak scenarios I've been thinking about for the past year or two: the imminent death of the net, the impossibility of digital privacy, and various impending threats, like government/corporate crackdowns on privacy, the disneyfication of the net and conversion to a digital Home Shopping Network, Alta Vista and the increase in dossiers, etc. If I'm in a good mood, I may also talk about how a very close friend of mine was fired for making "unflattering remarks" about her employer on the cypherpunks list. Here are the details: Date: Tuesday, March 12 Place: The Brecht Forum, 122 West 27 St., 10th Floor (NYC) Time: 8:00 p.m. Price: FREE (donation requested) --------------------------------------------- An anarchist forum presented by the Libertarian Book Club -- Dave Mandl dmandl(a)panix.com http://www.wfmu.org/~davem

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No Subject
by owner-cypherpunks＠toad.com 17 Dec '03

17 Dec '03

On Wed, 6 Mar 1996, Nelson Minar wrote: > The thing that bothers me about existing steganography code I've seen > is that it all uses uncommon communication channels to hide data. For > instance, the "hide data in a picture" programs: useful, up to a > point, but how often do I send pictures to other people? I think to be > effective, methods need to be employed that exploit existing, well > used communication channels. Then he sez: > So here's one idea I've had as a place to hide a channel: network > video, in particular CU-SeeMe video streams. CU-SeeMe is a lowtech I think it likely that people will be sending GIFs and JPEGs to each other far more often than video. Video is far more an "uncommon communications channel" than is a uuencoded picture. -- Ed Carp, N7EKG Ed.Carp(a)linux.org, ecarp(a)netcom.com 214/993-3935 voicemail/digital pager 800/558-3408 SkyPager Finger ecarp(a)netcom.com for PGP 2.5 public key an88744(a)anon.penet.fi "Past the wounds of childhood, past the fallen dreams and the broken families, through the hurt and the loss and the agony only the night ever hears, is a waiting soul. Patient, permanent, abundant, it opens its infinite heart and asks only one thing of you ... 'Remember who it is you really are.'" -- "Losing Your Mind", Karen Alexander and Rick Boyes The mark of a good conspiracy theory is its untestability. -- Andrew Spring

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Re: SEAL cipher info requested (something actually list related!)
by droelke＠rdxsunhost.aud.alcatel.com 17 Dec '03

17 Dec '03

> > Christopher Allen writes: > > At 4:27 PM 1/27/96, Anonymous wrote: > > >Anybody have info on the SEAL cipher? I can't find any > > >descriptions or analysis of it. Refs, proceedings or URLS > > >would be a good thing. > > > > I also am interested in references to it. > > > > I'm told that it was invented by a cryptographer at IBM, and that it > > patented, so that should help in the search. > > Its a Don Coppersmith creation. It is blazingly fast. I believe it is > patented. > > Perry > Get Applied Cryptography!!! - Page 398 in issue 2. Source code on page 667 Brief - steam cipher. Phil Rogaway and Don Coppersmith @ IBM. uses "pseudo-random function family". Fast. Patented. ------------------------------------------------------------------ Dan Oelke Alcatel Network Systems droelke(a)aud.alcatel.com Richardson, TX

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EFF on crypto bills
by Declan B. McCullagh 17 Dec '03

17 Dec '03

[In reply to Shabbir's message. -Declan] ---------- Forwarded message begins here ---------- From: Stanton McCandlish <mech(a)eff.org> Message-Id: <199603062155.NAA22301(a)eff.org> Subject: Re: NYT: Encryption compromise bill introduced To: shabbir(a)vtw.org (Shabbir J. Safdar) Date: Wed, 6 Mar 1996 13:55:07 -0800 (PST) Cc: declan+(a)cmu.edu, fight-censorship+(a)andrew.cmu.edu, jim(a)rsa.com In-Reply-To: <199603062014.PAA02169(a)panix4.panix.com> from "Shabbir J. Safdar" at Mar 6, 96 03:14:01 pm > The Leahy bill is actually much better than Stanton lets on. Take a > look at it, it affirms Americans' right to choose whatever algorithm or > technique they'd like, as well as takes great pains to go on record to > say that Congress treaded very carefully to preserve Americans' right > to not use key escrow algorithms, and if they did, not to use escrow > agents. You don't get much more of a guarantee than that. Sure you do: Goodlatte's more direct prohibition on the Exec. branch mandating Key Escrow. What's the problem here? We know Goodlatte's version, on this provision at very least, is better. Why can't we just agree that it is, and support that? Goodlatte's bill isn't competing with Leahy's, they were introduced simultaneously in different chambers, and are intended to get the same message across. I can't see a problem with saying "we like this particular phrasing better, let's have it in both versions." The entire point of all this is to have the same bill on both sides of Congress anyway. It can either happen early, or (on the off chance it ever gets that far) in conference committee. Here we have a large say. In conf. cmte. we have almost no say. Again, what's the problem? What are we arguing about? > Regardless of the ulterior motives of the White House, key escrow > programs are still voluntary as read on the books. The best we can > write into a law is to have our rights reaffirmed. Leahy has given > this to us in spades. I disagree. A better thing we can write into law is to simultanously have rights reaffirmed, and send a more direct message to the Admin that it cannot tread here. > Let's not soft-pedal this legislation. Let's not hard sell flawed parts of it, when fixes are not just available but already introduced as "live" legislation. > Leahy and Goodlatte are going > head to head with the White House to undermine the strongarm export > tactics of Clipper and Son of Clipper. They've stuck their necks out for > us, we need to back them up. Certainly. > Just wait until the White House starts to act in reaction to this. It's > not going to be pretty.... No kidding. I expect either an attempt to mandate escrow, a worsening of the export controls, and/or an all-out assault on American's rights to encrypt at all, or without some kind of worse-than-GAK registry or licensing. If not all of the above. -- <HTML><A HREF="http://www.eff.org/~mech/"> Stanton McCandlish </A><HR><A HREF="mailto:mech@eff.org"> mech(a)eff.org </A><P><A HREF="http://www.eff.org/"> Electronic Frontier Foundation </A><P> Online Activist </HTML>

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