- cypherpunks-legacy - lists.cpunks.org

Magic Money -> Chaum Cash
by nobody＠shell.portal.com 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Ok, let's try this one more time... Based on Eric's long and mathematical explanation, which I did not fully understand and was therefore convinced by, I have changed the program to use full Chaum cash. It takes the 16-byte random number, takes its MD5, and stores the MD5 in the coin. The coin is now a triple (id,e,mpi) and the bank never sees id when blind-signing the coin, thus preserving anonymity. I sent this new version to csn.org as mgmny10c.zip. I haven't had a chance to update the manual or the comments in the code, but it does seem to work. At least, I was able to mint coins and cycle them through the server a few times, so the basic coin cycle seems to work. Please check it out, on machines of both endians, and let me know what happens. Pr0duct Cypher -----BEGIN PGP SIGNATURE----- Version: 2.3a iQCVAgUBLVdfXcGoFIWXVYodAQExBQQAlAOtfHApmQlmj1bk2kdBEg+Rst0I4CcB vIoxQ/iXiAS5c9fGdl5WNWpBk5TYCQSHm3jyzAoYaeLwJ4XsgnH5WbvB+UeRzwJX VatnTUK7x7wZMtIBAAaaPGX2woosns83bnXMa5voKkiYeESFFLgU5Dw5zw24xFas 1fkwlBSnyRA= =L9Ei -----END PGP SIGNATURE-----

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WRONG: Attack on Magic Money and Chaum cash
by Hal 17 Dec '03

17 Dec '03

I was thinking over the attack I described on Magic Money and Chaum cash, and I now think it will not actually work, especially in the case of the Chaum cash. Specifically, it will take as much work to forge cash as to factor the modulus. My idea was to collect signed forms of small primes, then try to find a "smooth" number of the proper form, one which can be factored over this set of primes. By multiplying together the proper primes, one could generate a signed number which would look like cash. What I was remembering as I was driving tonight is that this is very similar to a family of algorithms for factoring large numbers. The one I know best is the continued fraction algorithm, but I think the number field sieve uses broadly similar principles. In the cfrac algorithm, the goal is to find two squares which are equal mod n. This lets you factor n immediatly by taking its gcd with the sum or difference of the two numbers. This is done by taking a bunch of squares and trying to factor them over a set of small primes. If you generate enough factorizations, approximately as many as there are primes, you can multiply selected ones together and generate two equal squares. The point is, finding as many smooth numbers as there are small primes will let you factor n. But that is the same criterion I had to meet in my proposed attack in order to make a profit. So it seems that in general my attack will not work; it will be as hard as factoring the modulus. There may still be a problem with Magic Money because its cash values leave the low order 128 bits free, but I'm not so sure about it. I was wrong, I think, to suggest that a simple sieve could quickly identify smooth numbers. Although a sieve will easily tell you that a number has _no_ factors less than some cutoff, it will not easily tell you that a number has _only_ factors in that range. It may be that the only way to identify smooth numbers is by trial division, which would be the same situation as for Chaum cash. So, unless there is in fact some trick that can be used to quickly find smooth numbers given that the low order 128 bits are free, I don't think there is any need to worry about my attack on Magic Money. And it looks like Chaum's online cash is completely invulnerable to this approach. Sorry to have raised a red flag unnecessarily. Hal

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Re: Clipper Side-step
by qwerty-remailer＠netcom.com 17 Dec '03

17 Dec '03

Beep say, "How about this as a way to stump Clipper? Generate a dialog between you and a friend of no relevant consequence. Load this sound byte into your system as a AIFC file (sound bite, or byte) Encrypt data/message/information/recipe/whatever into the low-bits of the sound bite." See my post "X's Last R". The problem is that PGP tattle tales on itself, it having no raw encrypted message output format (~indistinguishable from random data), and thus reverse steganography is trivial and can be automated. It could be less trivial if you use a steganography (hiding a message in another message) along with a secret scrambling routine for PGP messages, but then you are in the silly situation of "encrypting" an already encrypted PGP message! -=Xenon=-

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I support HR 3627
by hughes＠ah.com 17 Dec '03

17 Dec '03

Hey. You. Have you sent your letter of support to Rep. Cantwell yet? It's now even easier than ever! Just reply to this very message with your reasons for supporting the bill (it's to allow export of crypto software, dummy), and your mail will be automagically sent to the correct EFF address with the right subject line. (And don't include this message, OK?) For the full text of the bill, see any of the following: ftp://ftp.eff.org/pub/Policy/Legislation/cantwell.bill http://www.eff.org/ftp/EFF/Policy/Legislation/cantwell.bill gopher://gopher.eff.org/00/EFF/legislation/cantwell.bill Eric

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Re: A serious question of ethics
by nobody＠pmantis.berkeley.edu 17 Dec '03

17 Dec '03

On Mon, 7 Feb 1994, Tom Allard wrote: > -----BEGIN PGP SIGNED MESSAGE----- > > nobody(a)pmantis.berkeley.edu wrote: > > > Ok, I'm in a bit of a quandry. While surfing the net last week, I > > happened across an address addached to a machine that belongs the the > > federal reserve. No big deal. I telnetted there on a lark, and entered > > 'guest' for the account. It dropped me into a shell. It didn't ask for > > a password. Intrigued, I did a little looking around. Nothing special, > > a CDRom and about 80 accounts. But(!!), /etc/passwd was there and > > available and not using shadows. No, I didn't snatch a copy. > > - ------- Forwarded Message > > Date: Mon, 07 Feb 94 11:10:05 -0500 > From: m1rcd00 > To: m1tca00 > Subject: Cypherpunk... > > Guest login was denied this morning... > > Well, since someone seems to be home now at Minneapolis, if you wanted > to send something back to that list, I suppose it would be OK. If you > happened to mention in such a missive that the technical contact here > at the Board has no responsibility for or involvement with the Bank > machine or network involved, did not fuck up, and was not amused, the > technical contact would probably not mind. > > - - --Bob > > > - ------- End of Forwarded Message Does that mean that I no longer should report the open system (I don't dare telnet there to find out if it is the same one)? Also, and I'm purely curious, what actually became of my anonymous report, and do I need to be worried about SS agents in dark sunglasses coming to my home and dragging me away? (Truely worried and scared)

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Cantwell letter campaign - update
by Stanton McCandlish 17 Dec '03

17 Dec '03

In less that 24 hours, EFF has already received over *five hundred* letters in support of the Cantwell bill (which aims to take public crypto off the munitions list and relax export restrictions). Keep it up folks! If you'd like to add your voice to these letters, all of which will be delivered in hardcopy to Rep. Cantwell, send a "Subject: I support HR3627" message to cantwell(a)eff.org -- Stanton McCandlish * mech(a)eff.org * Electronic Frontier Found. OnlineActivist F O R M O R E I N F O, E - M A I L T O: I N F O @ E F F . O R G O P E N P L A T F O R M O N L I N E R I G H T S V I R T U A L C U L T U R E C R Y P T O

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Insecurity of anonymous remailers
by danisch＠ira.uka.de 17 Dec '03

17 Dec '03

> From owner-cypherpunks(a)toad.com Sat Feb 5 21:55:58 1994 > Date: Sat, 5 Feb 1994 15:21:18 -0500 (EST) > From: MatthewJ Ghio <mg5n+(a)andrew.cmu.edu> > To: Cypherpunks Mailing List <cypherpunks(a)toad.com> > Subject: Info on anonymous remailers > Content-Length: 1429 > Matthew J Ghio wrote: > I am pleased to report on the performance of our two newest remailers, > qwerty(a)netcom.com and nate(a)vis.colostate.edu. Both remailers had a very > good response time. Is it really a good idea to make anonymous remailers work so fast? Everyone who can analyze the traffic of anonymous remailers and can read the from/to header lines, the message size and the transfer dates immediately knows who sent mail to whom. The make the remailers more safe, I would suggest to modify the software: Every message must be sliced into pieces of standardized size ( e.g. 8K or 500 lines ). It should be possible to send the pieces over different channels. Every server should collect pieces and keep them a random time. Perhaps they could be collected until 10MByte of pieces are collected and then they can be sent out all. Every piece could contain a time limit which may not be exceeded by the servers. Higher limit means more confusion for a spy trying to follow this packet. The packets should be recyphered by every hop. They could have a random tail who's length is changed by a hop. A traffic spy could not find out which input and which output packets correspond. Hadmut

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What's a "real encryptor"?
by qwerty＠netcom.com 17 Dec '03

17 Dec '03

Typo correction from first post: If PGP outputted such a hard-to-distinguish-from-random data format, it opens up many different possibilities for sending your messages. Ideally, no one would be able to tell if it was an encrypted message except by successfully decrypting it. As it is now, such schemes have to rely on "encrypting" an already encrypted PGP message to hide the fact that it IS a PGP message! Many of us just want to be left alone and are tired of having our files tagged as BEING encrypted. Personally, I suggest using PGP as a Clipboard utility so I can cut a message out, encrypt it, paste it back in and save it as a word processor file which I then Macintosh BinHex encode as text, and e-mail off. Now I'm just sending a BinHexed word processor file, just like thousands of other Macintosh e-mailers out there every day! This isn't good enough since it is so easy to reverse, AND can be automated. Honestly, I'm not doing this much yet with distant friends, but then there are only two of them ;-), and they are still struggling with just e-mail. PGP is still a program only used by those why really need it. It may remain that way, so for those people, having a random data block output would mean they wont set off alarms and catch the attention of the government, just for sending a love letter to their mistress ;-). It would also render the Clipper issue moot. -=Xenon, who never could type, and breaks things a lot still=-

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T-shirt update - Please Read
by Christian Void 17 Dec '03

17 Dec '03

Several people have sent orders to me without including an e-mail address. This is not a problem, but I would like to confirm the orders so you know they were recieved. If you know this is you, or think it may be you, please send me a note. This is also the last call for orders. We will be taking orders until the 15th of February, so if you want one, send it ASAP. We will not be re-pressing the shirts, it is a one-time deal. Ordering information can be obtained via anonymous FTP to netcom.com: ~/pub/cvoid/cypherpunks/ordering.information.txt Christian Void /T71 | "I don't like it, and I'm sorry I | V/M/Research, Inc. cvoid(a)netcom.com | ever had anything to do with it." | P.O. Box 170213 Tel. 1+415-998-0774 | -Erwin Schrodinger (1887-1961) | SF, CA 94117-0213 * PGP v2.3a Public Key Available Via Finger *

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Oceania-history redoux
by an57322＠anon.penet.fi 17 Dec '03

17 Dec '03

It is interesting to read all the recent posts about Oceania, because it is of course the story of Sealand, an independent country that was founded in the Seventies. It would be wise if the promoters and future citizens of Oceania studied the failure of Sealand before putting another dime into their doomed project. Shortly after Sealand was funded on a large surplus housing platform in the oil fields of the North sea, Sealand began issuing its own currency, passports, and stamps. The results were predictable: nobody wanted their money, no other country accepted their passports for entry, and the international postal organization refused to deliver their mail. IMHO, there can be little doubt that Oceania would suffer the same fate-if the project ever gets a far as having a platform. The nations of the world are like a very exclusive country club: no new members accepted. Occasionally, a former member gets readmitted, or one member dies and her two children take her place, but there will be no newcomers. -= T.A.Z. ------------------------------------------------------------------------- To find out more about the anon service, send mail to help(a)anon.penet.fi. Due to the double-blind, any mail replies to this message will be anonymized, and an anonymous id will be allocated automatically. You have been warned. Please report any problems, inappropriate use etc. to admin(a)anon.penet.fi.

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