December 2003 - cypherpunks-legacy

Re: Spinners and compression functions
by JonWienke＠aol.com 17 Dec '03

17 Dec '03

In a message dated 96-04-08 04:01:28 EDT, stewarts(a)ix.netcom.com writes: >Data contains varying quantities of predictablity and unpredictability. >Some of the predictability has simple enough structure that a basic >compression function can find and exploit it to squash the data. >Some of the predictability doesn't. For what it's worth, compressing >the data before using it for other things does leave you with somewhat >more consistent entropy per byte for "typical" random input, because it >eliminates the easy stuff. That was the entire point of my original posting on this subject. I was proposing using a compression function on spinner data, which contains very little entropy and compresses well. (50 - 80% on idle loop timing data, depending on processor load) I don't believe I said anything about compressing image data of any kind, or audio recordings of humpback whales doing the wild thing, etc. Noise sphere plots of ZIP files look pretty good, regardless of how good or bad the plot of the unZIPed file looks. (Raw idle loop timing plots are terrible.) I have posted a longer reply to Perry via E-mail... Jonathan Wienke

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Re: They're running scared.
by Michael C. Peponis 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- On Sun, 07 Apr 1996, jim bell wrote: [article snipped] >Articles such as this are interesting because they appear to be written >without any illusion that the interests of governments are anything other >than just that, interests of governments. They are NOT the interests >of the average citizen. Absolutly, and it seems that more and more thinking people are realizing this, as for the non-thinking ones, well we are better off without them, the only thing they contribute are problems Debate works to a point, but there comes a point and time where all that can be said, has been said, and we are past that point. Personally, I love national insecurity such as terrorist attacks and random bombings, wish there were more of them by more people. What they do is sow fear, instensify camps, and pit people against each other. Goverments are use to wars, where there are large, well-defined groups assult one another, they have huge problems dealing with small groups of people attack it or each other. That is what will eventually cause it to collapes, which is a good thing. For those who say that such an event would be catostrophic, that is a myth, I worked with someone from Berut a few years ago, when the goverment there collapesed. He said other than the perpetual mortor fire, and speratic bombings, life went on as usuall. People got up and went to work, people bought and sold, etc. From a microsopic scale, nothing had changed, it was only if you looked at the bigger picture that things were different, and quite frankly, those types of things do not effect us individually. I do not need an x trillion dollar economy to continue living at my standard of living, most of us on this list do not, the only people that benifit are the power brokers and the dumb, weak, and stupid. I have nothing against charity(that's what taxes amount to), but when charity reaches 50%+ of my income, and starts to erode my freedom, well now it's a problem. -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: cp850 iQCVAwUBMWkWWUUffSIjnthhAQHEiQP/Sp5+UfCFGmvEO/9nRFBLXBm9haPiJC/y oVCoKQi/jeCkXy1HaPjrrObFkV0fvRsHxk5GvHXfX9sIkFi/i9mrGafpXFUuRfkP qua2wYp91Omh39QptHThGgEKl0sdKBzw+/9uHCqwUyViqoZZBO7Y7kUGffT9XL9m 13VTjMTyFz4= =e+UM -----END PGP SIGNATURE----- Regards, Michael Peponis PGP Key Available from MIT KeyServer

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Bank transactions on Internet
by Jüri Kaljundi 17 Dec '03

17 Dec '03

Suddenly some banks here in Estonia have decided that they must start offering banking services over Internet already during the next months. What worries me is that some of them are talking about using 40-bit SSL as the main security mechanism. What about banks in US and Europe, how many of them are using Internet and WWW to offer their services already? Is it possible to use WWW forms to make real transactions or can you just view your transaction history and account status? In case the banks are using WWW forms and SSL, are the services limited to 128-bit clients? How is the client authentication handled? Does the client just get a plain username and password? I had a look at some banks like Security First National Bank and some others, and it seems that they use just SSL + username/password for they banking services. Does this really work, especially with 40-bit keys? SSL with client certificates would seem a little bit more secure once it is available, but still not secure enough for real banking on Internet. Just curious (and confused), Juri Kaljundi jk(a)digit.ee

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why compression doesn't perfectly even out entropy
by Perry E. Metzger 17 Dec '03

17 Dec '03

Jon asked why it is that I contend that a compression algorithm won't in the general case even out the entropy of a semi-random stream. The answer can be obtained by simply trying to run gzip over an image, preferably one that hasn't been compressed. The results are, in general, very bad, even though images are highly compressable (even losslessly). I leave the why up as an exercise to the reader. I have said before and I will say again that the only reliable way of dealing with a stream that has some amount of randomness mixed in with it that you wish to distil down into pure random bits is to use solid reasoning to figure out how many bits of entropy per unit of input you can actually expect to see, add a large fudge factor to cover your ass, and then distil down using a cryptographic hash. Anything else makes me highly nervous. If you can't estimate the amount of entropy in an input stream from first principles, then you are probably in trouble and should seek an input stream that you have a better handle on. Perry

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Re: the cost of untracability?
by tcmay＠got.net 17 Dec '03

17 Dec '03

At 7:53 PM 4/7/96, Jim Gillogly wrote: >jim bell <jimbell(a)pacifier.com> writes: >>FWIW, I think that there is no capital-gains-type tax on currency >>conversions. In other words, if I take dollars and buy yen today, and the > >I bounced this off a CPA, who said she would be very suprised if this is >really the case: in general the IRS considers increases in wealth to be >taxable, and unless there's a specific exclusion for currency transactions >that she doesn't know about, she suspects this is not the case. As a >conceptual counterexample she points out that you are responsible for any >profit you make from selling your car for more than you pay for it (but, >as you might expect, you don't get to take a loss if you sell it for less). I think your CPA is clearly misinformed, or one of us has misunderstood the conditions under which her statement is true. For example, I read a fair number of corporate earnings reports, and can assure you that many companies report gains and losses on currency conversions. (Many companies use derivatives to hedge themselves against fluctuations in foreign currencies....) Similarly, if I consult the "Wall Street Journal" I find page after page of listings for currency prices, futures on currency prices, derivatives involving said currencies, and so on. I can easily be a "currency speculator" by calling my broker. It may come as a surprise to this CPA (and Jim Bell, from his later message), but gains in this market are taxable, and losses can offset gains, subject to the usual mumbo jumbo rules. It is certainly true that if one converts $300 into yen for a trip to Japan, to have to buy a few beers for cash (Tokyo is expensive), and upon returning to the U.S. their has been some slight gain (yes, a "profit"), that the IRS is not interested. This is a matter of practicality, given that such minor conversions are usually done in cash form, are too small to worry about (minimal gains...a few bucks in the example shown, and usually more than erased by the conversion rate differential). Try speculating _seriously_ in the dollar-yen conversion rate, through the various options listed in financial newspapers, and then telling the IRS that a $100,000 profit, say, is not taxable because of what a CPA said. --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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Re: (Fwd) British Study Claims That Photo Credit Cards Don't Work
by David Loysen 17 Dec '03

17 Dec '03

At 12:58 AM 4/8/96 +0000, you wrote: >This comes from the FTC Privacy List, and is somewhat relevant.... >(The the "Crypto" in the title isn't, oddly...). > >Some thoughts... (er, questions): >1. What are the implications for log-on systems that rely on >recognition of faces (supposedly impossible for hackers to describe >and exploit)? Does anybody know how well these systems work? If I don't shave over the weekend will my computer know who I am Monday morning? Is my credit card going to have my face digitized and encoded onto the mag stipe for comparision with a video camera image at the time of sale? >2. Legal implications for witnesses? > I think many eyewitness accounts are already taken with a grain of salt, at least as far as picking a suspect. Certainly in court the lawyers say whatever makes their case look better. >------- Forwarded Message Follows ------- >Date: Sun, 7 Apr 1996 08:24:18 -0700 >From: taxhaven(a)ix.netcom.com (Adam Starchild ) >Subject: British Study Claims That Photo Credit Cards Don't Work >To: privacy(a)ftc.gov > > "Crypto-ID" Cards Not Effective > > Recent studies into the effectiveness of photo credit cards >have cast doubt over their ability to cut fraud. Dr. Richard >Kemp, of the Department of Psychology at Westminster University, >London, organized an experiment involving a London supermarket to >test the cards in "the real world." Most if not all credit card issuing banks use some form of fraud detection software. The next generation of these products will be analyzing transaction data from the card clearing banks in real time to stop fraudulent transactions before they are complete. Expect to see more "may I see your ID" questions as these systems flag transactions as possible fraud. I have had a credit card with my photo on it for several years, I can't ever remember a sales person who seemed at all interested in comparing the photo to me. > The supermarket was staffed by six people who were all >warned to be on the look out for fraudulent credit cards. Dr. >Kemp arranged for 44 of his students to pose as shoppers and test >the staffs' ability to spot photo-card misuse. Each student was >armed with four cards. One showed the student as they were, one >showed the student wearing make-up, one showed an individual who >vaguely resembled the student and the last card depicted someone >who looked nothing like the bearer. > People usually recognize photographs of individuals based on >a familiarity of the subject. A photograph captures only one >angle and expression out of thousands of different combinations. >People will recognize photographs of family, friends and well >known individuals easily. But how easy is it to accurately >compare a photograph with the face of a perfect stranger? At a >recent conference, Dr. Kemp said that matching a photo to a >stranger's face was "too difficult." He also said that in a non- >experimental situation, such as a supermarket, the incidence of >fraud detection would be even lower. > The results of Dr. Kemp's supermarket experiment proved very >interesting. In all, the majority of fraudulent cards were >accepted. Amazingly, 35 per cent of the cards bearing a >photograph of someone completely different from the student were >accepted. A massive 64 per cent of cards bearing a similar >individual were also accepted. Another factor which seems to >further prove Dr. Kemp's point is that 14 per cent of cards >bearing a true likeness of the student were rejected. > A few British banks are already offering customers the >opportunity to have their photograph etched onto their cards. >They claim a reduction in fraud has resulted from this. Dr. >Kemp's findings would seem to contradict this belief. Dr. Nicky >Towell, one of Dr. Kemp's researchers, said "There is a widely >held assumption that photo credit cards are a cheap and effective >way of stopping fraud. But this is not the case." > No one can tell how well photo credit cards will catch on. >But with the majority of people carrying at least one, if not >more cards of some sort, how long will it be before photos become >compulsory? The government knows that the introduction of ID >cards is a political hot potato, but how many people would notice >if they turned the cards we already have into crypto-ID cards? > > >Reprinted from The Mouse Monitor, The International Journal of >Bureau-Rat Control, a periodical published by Scope International >for its customers. Scope International is on the Worldwide Web >at http://www.britnet.co.uk/Scope/ > > >Posted by Adam Starchild > The Offshore Entrepreneur at http://www.au.com/offshore > > > >The privacy list is run automatically by the Majordomo list manager. >Send a "help" command to majordomo(a)ftc.gov for assistance. > >Rob. > >--- >Send a blank message with the subject "send pgp-key" >to <WlkngOwl(a)unix.asb.com> for a copy of my PGP key. > > dwl(a)hnc.com David Loysen 619-546-8877 x245

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Re: Spinners and compression functions
by JonWienke＠aol.com 17 Dec '03

17 Dec '03

I received this via private email, and have been asked by the sender to post to cpunks. >Subj: Re: Spinners and compression functions >Date: 96-04-08 12:49:29 EDT >From: eli+(a)GS160.SP.CS.CMU.EDU >Sender: eli+(a)GS160.SP.CS.CMU.EDU >To: JonWienke(a)aol.com > >In article ><+cmu.andrew.internet.cypherpunks+clNRbLm00UfAE109Nf(a)andrew.cmu.edu> you >write: >>Run the spinner output through a PKZip type compression >>function, and then seed a PRNG with the output from that. This would >provide >>a means of gauging the amount of entropy that has been fed into the PRNG, >>(count the bytes output from the compression function) which will allow the >>program to disallow any output from the PRNG until a sufficient amount of >>entropy has been fed into it. > >If pkzip were a perfect compressor (which doesn't exist), this would >work well. What you're doing is measuring entropy with respect to >pkzip's model of the input language, which can be arbitrarily far off >from the entropy you'd get with a more powerful model. This means >that an attacker who understands the video retrace (or whatever) can >get an edge on you. You really can't tell if data is random by >looking at it -- for example, Nisan published a generator based on >universal hash functions that provably passes all space-bounded tests, >which most statistical tests are. > >Compressing the data probably won't hurt (*probably*, and assuming you >take the header off!). But Unix compress won't make data look >statistically random, and I doubt pkzip will either. Neither one will >give you a useful estimate of the entropy in the data stream. You >have to guess that yourself, and then use a strong hash function to >get it down to that point. > >-- >. Eli Brandt usual disclaimers . >. eli+(a)cs.cmu.edu PGP key on request . >. violation of 18 U.S.C. 1462: "fuck".

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International Net-Censorship Efforts Update
by Declan B. McCullagh 17 Dec '03

17 Dec '03

I've just doubled the number of international net-censorship efforts that I track on my web page: <http://www.cs.cmu.edu/~declan/zambia/>. Included are new updates reporting on Germany, France, Australia, Singapore, Canada, and China, among others. Please send me reports on countries I've missed! -Declan -------------------------------------------------------------------------- OTHER INTERNATIONAL NET-CENSOR EFFORTS By Declan McCullagh declan(a)well.com http://www.cs.cmu.edu/~declan/zambia/ France, China, Germany, Singapore, Jordan, the U.S., and many other countries are moving towards tighter control of the Internet. France and Germany want to see an international agreement of information controls emerge. Recently China required all of its estimated 40,000 Internet users to register at the local police station. This international crackdown marks a turning point in the development of the Net. Germany Germany cuts off access to holocaust revisionist web site (1/96) German Internet update, new laws planned (3/29/96) Los Angeles Times on German vs. U.S. netcensorship (3/13/96) German minister predicts collapse of governments (3/12/96) Germany's CompuServe net-censorship (12/31/95) France French government bans controversial book (1/96) French Jewish students sue ISPs for revisionist materials (3/14/96) French Jewish students sue ISPs for revisionist materials (3/15/96) France calls for "global Internet rules" (2/3/96) Europe Swiss statement on voice over Internet (3/16/96) Sweden proposes CDA-type law to control Internet (4/3/96) Italian net-censorship necessary, says Simon Wiesenthal Ctr (1/11/96) Turkey cracks down on Internet (2/18/96) Belgium bans non-escrowed encryption (1/10/96) Asia and Pacific Rim Singapore leader condemns Net (3/7/96) Indonesia attacks Net (3/11/96) Malaysia complains about uncensored Net, censors it (3/11/96) Singapore censors political, religious net.info (3/6/96) China China cracks down on Internet, "state security" cited (1/24/96) China's anti-cyberporn efforts (2/4/96) New York Times on China's net.crackdown (2/5/96) China's history of Net-regulation, cyberporn concerns (1/1/96) China requires Internet users to register with police (2/16/96) U.S. State Dept criticizes China's net.censorship (3/8/96) China applauds German net.censorship (1/11/96) Australia Australia considers net.legislation (2/13/96) New South Wales tries net-censorship (4/3/96) Australians upset by German Zundelcensorship (4/7/96) Canada Letter to Canadian minister (3/19/96) Canada needs to regulate Net, says Simon Wiesenthal Ctr (2/20/96) Middle East Persian Gulf States reluctant to move online (4/6/96) Jordan installs Internet screening facility (1/8/96) Saudi Arabian government says no unrestricted Net access (1/10/96) --------------------------------------------------------------------------

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Re: "Contempt" charges likely to increase
by rngaugp＠alpha.c2.org 17 Dec '03

17 Dec '03

This is why raw symetric ciphers should be used, without headers. PGP should have an option to omit its headers when using the -c switch. People should not be forced to use outside programs such as stealth. In the absence of cryptanalysis, the output of a symetric cipher looks like random bytes. Every one should have a hardware RNG on their computer. "I am sorry your honor, that is a file of random numbers that I was using to check the output of my RNG." Or "I am sorry your honor that is a one-time pad I was planning to use." Or how about the purloined letter method? A few years back, a hack to PGP was published, which gave the user the option of directly controling the idea key used when encrypting/decrypting with RSA. There even was a option to make the idea key used in encrypting key wrong (that is, different than specified in the encrypted RSA message). "I am sorry your honor, that file is encrypted so that only obiwan(a)galaxy.far.far.away can decrypt. It is too bad that obiwan is outside the jusisdiction of the court." (But in fact I can decrypt by directly specifying the idea key.) By using the wrong idea key, I can fix it so that in the unlikely event that someone finds obiwan, obiwan finds that his secret key does not work. (Because the key decrypted by RSA is wrong.) With a little thought. you could change the above senerio to use obiwan(a)alpha.c2.org and fix it so that obiwan does not actually exist, and his secret key has been destroyed. (Create obiwan(a)alpha.c2.org, but fixit so that his reply block points off into the weeds. Create a public/secret PGP keys for obiwan and send the public key to the public key servers, using remailers. Using remailers, publish a few signed articles in obiwan's name. Then wipe obiwan's secret key with pgp -w.) You can now claim that you started a private encrypted conversation with obiwan(a)alpha.c2.org. Who unfortunately can not be found.

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Re: RC4 improvement idea
by nyap＠mailhub.garban.com 17 Dec '03

17 Dec '03

> I got a paper from the cryptography technical report server > "http://www.itribe.net/CTRS/" about a weak class of RC4 keys. The > report said that with some keys, it was possible to predict what some > parts of the State-Box would be. I was thinking of a way to fix this, > and had this idea: > > do some sort of hashing function with the key that derives a number > between 55 and 500 or something like that, then scrabmle the S-box that > many times. In this way, the chances that the State-Box will have any > correlation becomes extremely small. I think it is 1/125 to begin with > anyway, so this would make it around 1/(125*NumPasses). And since the > exact number of passes is a function of the key, the cracker won't know > how many times it went through. I tried this out and having 1000s of > passes doesn't effect the randomness of the state-box in any negative > way, possibly it makes it more random? If anyone has any thoughts I'd > love to hear them. The S-Boxes in DES were optimized to hinder Differential Cryptanalysis. I've seen no studies on the effectiveness of jumbling the S-Boxes during encryption -- even Biham and Shamir's book doesn't mention it -- but, I figure, if it helps, DES would probably already be doing it (unless of course the NSA thought the jumbling would make too good an algorithm).

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