December 2003 - cypherpunks-legacy

forward secrecy in mixmaster
by Adam Back 17 Dec '03

17 Dec '03

Since Peter Allen's discussion of mixmaster, I started doing something I'd been thinking of for a while, since noticing that it was on the mixmaster to-do list months ago (ie there is unfinished source to do this): direct socket connections and diffie-hellman key exchange for forward secrecy. I wrote the socket stuff yesterday evening, didn't take too long as socket programming is something I've done lots of. Now comes what do you actually send down the sockets. Question for Lance, and any others who were involved in mixmasters implementation: what did you have in mind as a way of negotiating the DH keys? I notice that mixmaster generates a DH key and stores it in file `DH.mix', but that this is not (as far as I can see from the source) included in the remailers public key block. (A couple of comments as an aside: I think that you should be able to have a much smaller generator without loss of security, this should reduce the overhead of a DH key exchange. Using 3 even I think is safe, without any extra precautions on prime generation. You can even go to 2, with a few precautions (PGPfone does this). Comment #2 I think 1024 may be a bit small, I don't have any figures handy for relative security of DH key lengths, but PGPfone offers 4096 bit DH for instance. Does rsaref have limits on prime lengths for DH, the same as it does for RSA?). There are lots of options for DH public key negotiation. First option is whether you have a common prime and generator for all remailers or not. If you have a common prime, accusations of the prime being `cooked' (chosen to have a weakness) can be mitigated by using a deterministic generation method based on the hash of a known phrase (a Jefferson quote perhaps), or PI or whatever. A common modulus may offer a fatter target for attack (for some precomputation attacks), but with large enough keys this probably isn't that bad, as there aren't that many mixmasters anyway. With a common modulus there is DH key negotiation needed, just include it with the source. For different modulii for each remailer, there are more options: a) include the DH key signed by the RSA key in the remailers public key (may break backwards compatibility with existing versions of mixmaster) b) send the DH public key at the start of each session c) send the DH public key on request There is also a question of which key do you use, the sender remailers or the recipient remailers. Negotiating DH public keys during execution also opens the possibility for periodic re-keying. Thats the end of my thoughts on direct socket mixmaster. Next message is some thoughts on non-interactive forward secrecy protocols. Adam -- #!/bin/perl -sp0777i<X+d*lMLa^*lN%0]dsXx++lMlN/dsM0<j]dsj $/=unpack('H*',$_);$_=`echo 16dio\U$k"SK$/SM$n\EsN0p[lN*1 lK[d2%Sa2/d0$^Ixp"|dc`;s/\W//g;$_=pack('H*',/((..)*)$/)

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non-interactive forward secrecy
by Adam Back 17 Dec '03

17 Dec '03

[This discussion is driven by the desirability of having forward secrecy in mixmaster for the mix packets delivered by email where the interactive nature of normal DH is incovenient] Anyone have any ideas for a non-interactive forward secrecy protocol? Aside from actually doing the DH key exchange via email (painful), I have one suggestion for a protocol, perhaps people can improve on this: Assuming common prime p, and generator g: Two remailers A and B. A wants to send messages to B without having to wait for replies from B. B generates ys (y0,y1,...,yn), where y(i+1) = hash(y(i)) then computes Ys (Y0,Y1,...,Yn) where Y(i) = g ^ y(i) mod p B sends A Ys, and discards ys. Now A can send B n consecutive packets with forward secrecy before receiving any more packets from B. (B keeps y0, and overwrites it with y1 = hash(y0), etc, so that all B ever has to hand is the current y(i), and y(i-1) is hard to compute from y(i) because of the hash functions properties.) This isn't truly non-interactive, it just reduces the number of interactions, to an interactive exchange in 1 out of n cases. (you could randomly chose ys rather than having related ys, and delete y(i) after use, but this has higher storage requirements (n rather than 1 on the recipient)). Heres the obvious construction for a truly non-interactive forward secrecy protocol based on DH. (That is it only requires 1 interactive exchange). Aside from the obvious of having a huge n, and the above protocol, which would have large space requirements, what we're after is a way to do this with negligable space requirements. Say that we have the two parties Alice and Bob. Bob doesn't loose much by having his secret (x) related as above. 1. x(i+1) = f1( x(i) ) 2. X(i+1) = f2( X(i) ) 3. f1 is non reversible f1 should have hash-like properties (it should be non-reversible). Do functions f1 and f2 satisfying 1, 2 and 3 exist? Is there another way to achieve this? (My closest attempt so far, based on the hardness of discrete square roots: f1(x) = x^2 (mod p) f2(X) = X^2 (mod p) doesn't work because g^(x^2 mod p) mod p != g^(x^2) mod p) Adam -- #!/bin/perl -sp0777i<X+d*lMLa^*lN%0]dsXx++lMlN/dsM0<j]dsj $/=unpack('H*',$_);$_=`echo 16dio\U$k"SK$/SM$n\EsN0p[lN*1 lK[d2%Sa2/d0$^Ixp"|dc`;s/\W//g;$_=pack('H*',/((..)*)$/)

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Re: MUD anyone?
by jim bell 17 Dec '03

17 Dec '03

At 10:06 AM 9/1/96 +0000, Rev. Mark Grant wrote: >On Tue, 27 Aug 1996, Jon Leonard wrote: >Protection Agencies >Escrow Agencies >Private Law Courts (probably controlled by players rather than the computer) >Reputation Agencies > >> What am I missing? Should there be direct support for Jim Bell's >> assasination markets? It'd provide a means of demonstrating its >> ineffectiveness as a means of social control. > >I think it should be incorporated, but I think that people can set them up >easily themselves. Perhaps we should have an NPC-run 'Assasins Inc' which >would run the lottery, and then players could do the actual 'wet work'. > >But yes, I'd really like to see how this would work in the game. As I >said I'm thinking of this more as a semi-scientific experiment than a >pure game. We have some idea of how this stuff should work in theory, but >little of how it works in practice. > >I do think though that we'd have to enforce some kind of rule against >'disposable characters', otherwise people could simply create a new >character every time they were killed trying to assasinate someone. There >would need to be some disadvantage to just going in guns-blazing and being >killed ten times in a row. Wouldn't it be more realistic if instead of representing individual characters, you created composites which had a "weight" based on how many of them exist in the country/world? For example, the character "buggy-whip maker" in 1900 would be weighted in the thousands, while his number would be drastically reduced a few decades later. This would avoid the "going in with guns blazing" scenario, or at least it would put it into perspective: the number of assassins would drop by "1" (or some proportion) if that happened, although correspondingly the number of targets would also drop. With this system, a character would never die, but his number would simply drop to an insignificant quantity. ("Government-thugs" comes to mind...) And that's not the only reason the number of characters would drop: If it suddenly became "unhealthy" to accept a public paycheck, and thus the risk wasn't matched by the rewards, presumably people would shift professions. Again, this would all be part of the simulation. Jim Bell jimbell(a)pacifier.com

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Re: Court challenge to AOL junk-mail blocks
by Will Rodger 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- At 12:27 PM 9/7/96 -0700, Declan McCullagh wrote: >If AOL wants to stop spammers, let them. They have every right to do so as >long as their agreement with their customers permits it. It's a matter of >contract law between AOL and its customers and should not involve the >spammers and a lawsuit brought by the spammers. > >It seems as though the judge was snookered by the spammers' claim of U.S. >Mail-like service, free speech, blah. The right to free speech does >extend to corporations; in that way, it includes the right *not* to speak. > Declan raises a good point. But I'm guessing it's a bit more complex than that. CyberPromo and AOL lawyers tell me the court slapped down AOL simply to "keep the status quo." Both sides used those very words, in fact. What's more, CyberPromo talks a good game on the First Amendment, but used computer fraud and unfair competition statutes - not the Bill of Rights - in its original filing against AOL. So what's going on? It seems Weiner is _very_ aware that this case deals with things never before argued in court. No one has really sorted out just how much e-mail - if any - an ISP is obligated to carry against its wishes. What Weiner decides this fall may not set the kind of precendent that the case of the Pentagon Papers did, but will be important for a while at least. Will -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQEVAwUBMjIIw0cByjT5n+LZAQFNWgf/Xb+yG9JDVZ6MN1Hz/K4IUCXL8hSgjeG3 +Ih+aXiod/vVAHXCJmktvBJFWWAJjpFjW/0WQljvsMULxXYpdXAYFDh4kiZZg4A3 7xkjCsT+Kpi8lDCRmFPciQfvoLyiEJxr8hI2l2qucE0THV0spysTKpgYueggLZI6 no5mC47ZGusfL9jWb7qrnbqjO1h+0mVZYgr0GRY8MVvyMsJGgylEDaiCh0KSaI1V TqEfTF+kcbzqtht0yG/M+QmCRertH4s1y9IWllWvJLMbAfwgFCxgGtamWoyXiHye keXAGLK0r2u8vTfwK5rJ91ZR774CGkZHulNi3wx53pZaFyYPJtYizA== =KS50 -----END PGP SIGNATURE-----

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Re: Metcalf and Other Net.Fogies
by John Brothers 17 Dec '03

17 Dec '03

At 11:17 AM 9/7/96 -0400, perry(a)piermont.com wrote: > > <snip discussion of internet collapse> > >I'm "involved with the problems" too, you know. Don't teach granpaw to >suck eggs. OF COURSE there are problems. None of them, however, are >signs of "collapse". This whole thing makes me ill - maybe I'm just an idiot. What could possibly cause a collapse? More usage?? No - that would just mean that everyone's access would be slower. Do routers fail because they can't talk to other routers? no - they route around it. I consider myself reasonably educated when it comes to the layout of the internet, and I have never heard _anyone_ ever say what constitutes a collapse, and, if it means 'catastrophic permanent failure of the Internet', what could possibly cause that. These people are acting like one day, something is going to blow up, and the entire internet will follow, and stay down for a long long time. If all the DNS servers died, the internet would stop working for non-local access until they recovered. If there was a bug in Cisco routers that was set to go off on Thursday, September 12th, that would render them inoperable until power cycled, that would cause a major failure. If every building in MCI and Sprint's data network blew up, that would cause a major failure. If the usage increased so that the Internet was 'saturated', that doesn't qualify as a collapse. It qualifies as 'rush hour'. If the internet was in 'rush hour' 24 hours a day, it would be unfun to use, but unlike the highway system, we can add more lanes pretty much at will. (within reason). Will someone please explain to me what I'm missing? Thanks John --- John Brothers Do you have a right not to be offended?

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Re: [RANT] Death of Usenet: Film at 11
by attila 17 Dec '03

17 Dec '03

In Cypherpunks, on 08/19/96 at 01:34 PM, mpd(a)netcom.com (Mike Duvos) said: =If Singapore bans alt.sex.hooters, you could simply post to =alt.culture.singapore.i.got.your.hooters.right.here. [snip] =It would also send the correct message that "newsgroups" are simply =one of many labels on an article, and are not cyberspacial tearooms =where bad people congregate and there is guilt by association. I don't fault your argument on "sending the correct message," but since when has an oppressive government ever been concerned with "the correct message?" LEA's could care less about the message; their only interest is another opportunity to behave like the jack-booted thugs they generally are. but public opinion, certainly the government interests in control, have already determined in the court of small minds that "we" are inherently evil (and beyond redemption without coercion). A repressive government can not afford publications from unredeemed (and unrepentant) cyber-anarchists with a world wide audience. Is the daily comics the last refuge of freedom; witness today's "Thatch:" "cubicle cliches are one of the few things we all share; they're one of the few things that unite us as americans!" "that and utter, corrosive contempt for our elected officials." sarcasm has always been a potent weapon, and one of the hardest to silence. ..in bits and pieces it can slowly undermine the target. why is it tolerated? I'm sure our malicious uncle wanted to shut Doonsbury down during Vietnam, but joe-six-pack rarely understood the underlying message. =The alternative to doing something reasonable like this is probably =to see mass migration from "banned newsgroups" to off-topic groups, =like Lolita pictures in rec.pets.cats, when the inevitable crackdown =comes. has not the crackdown arrived? and are not the various skirmishes between governments on one side and the ISPs & users on the other sufficient evidence of governmental intentions? =As long as people can post =anonymously, they will simply switch to another existing newsgroup =when the one they are posting to becomes blocked. Once the =inevitable reciprocal pissing contest between posters and censors =gets going, Usenet as we know it will likely be destroyed. let's put it this way, the first reaction will be to "eliminate" the anonymous remailers, then ban the "alt" groups which can be created at will. if there is migration from alt.sex.binaries to rec.cats, the government will eliminate the entire usenet and we will be forced back to the NWO controlled media conglomerates, or mail lists. of course, then the fascists will block or close down the list servers on some flimsy pretext such as violating the US postal monopoly and regulations.... Many companies block the alt groups; 15 years ago, even I blocked the alt groups during business hours (and usenet was only 1.5 MBytes per day then!), restoring them at 1800. --why? because the office staff spent *at least* all morning reading usenet, occasionally even refusing to talk to customers before their daily dose! My point is simple: I reacted by limiting the **time** of access, ** not access itself. ** On the other side, Reed, Buchannan &c. have decided *they* should judge what is fit (G rated) for our consumption; and, of course, Big Brother has determined they should be the judge of political correctness and all that shit which is numbing the minds of joe-six-pack until America is a controllable homogeneous bowl of putrid gruel. government, in and of itself, may be able to selectively prosecute cyberspace "violaters," but the real danger is big business. Print newspapers receive $64 billion in ad revenue, 80% of which is local. Virtually every major US newspaper (most owned by the group of 5) has a net presence --some very informative. And, even Mexico has more than a dozen of their papers on line. However, in the US the news is still the same collection of what the NWO wants us to hear/see. So far, the foreign press is not so inhibited and is often openly critical of US bumbling in foreign affairs, Bubba's alleged (alledged?) cocaine habit and criminal behaviour, --likewise critical of all fools. Where does this lead? Well, we've probably peaked on freedom; the rest is downhill as our "non-elected" government degenerates to deploying more and more thought control to maintain the oligarchic fascist form of what Jefferson thought they were creating as a representative republic. I for one enjoy tweaking their nose, but it only stiffens their resolve to squash me/us/whatever. How do you show resolve without being in their face? most regulation is created to "eliminate" abuse of a "public" privilege; unfortunately, we all suffer "collateral damage" to use their term. does voluntary compliance work? unfortunately, no. where does that leave us? confrontation, I guess. preserve our advantage as long as we can. we all know from münchen that Clement Atlee made a fool of himself appeasing Hitler for a false peace. might as well carry on with what we do best: rape, pillage, and burn... a scorched earth policy....

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Re: "The Bill of Rights can be dangerous...." (fwd)
by Jim Choate 17 Dec '03

17 Dec '03

Hi all, Forwarded message: > Subject: Re: "The Bill of Rights can be dangerous...." > From: dlv(a)bwalk.dm.com (Dr.Dimitri Vulis KOTM) > Date: Sat, 07 Sep 96 09:35:38 EDT > > I remember beig surprised to discover that the library computer at City > University of New York (state school where I got all my degrees) had an > (easily accessible) record of every book I've ever checked out in some > 15 years, And by the way you need to present A LOT of ids to take books > out of New York's public libraries, or to use the public-access > computers in them. And by the way you're asked to sign your name and > affiliation (fortunately, no ID is required) if you want to just enter > NYPL's Slavic division and use their reading room. Apparently this was > instituted during the cold war under the assumption that anyone > interested in Slavic Division's materials needs to be watched. In the very early 80's while I was attending UT Austin the FBI approached the libraries and requested access to the loan records. The libraries refused and went so far as to post a warning at each of the book checkout points on the event. Personaly, I was very proud of them for the refusal and the extra step of the warning. > A very good friend of mine does EE for a living, and in particular he > sells some EE equipment by mail order. He told me that every time he > sells something like the gizmo to write magnetic strips on credit cards, > he gets a phone call from los federales saying: you sold X who paid with > Y and shipped it to address Z - do you have any additional details? He > says every time they know as much about the sale as he does. :-) I have been dealing with security electronics for over 10 years and have never been approached by anyone regarding my activities. I make no secret of the fact that I do that sort of work as well as being able to build custom equipment if needed. I would suspect that there is a flag on your friend for something or someone from the past, not on his business in particular. Jim Choate CyberTects ravage(a)ssz.com

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Choice of Words
by attila 17 Dec '03

17 Dec '03

> --Tim May, who hopes he is never identified as the "John Doe" indicted, > tried, convicted, and sentenced in 1979 in Washington County, Oregon, for > the crime of unlawful foddering in a public place. > foddering? why, are you an indiscreet luncher? > 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, > Licensed Ontologist | black markets, collapse of governments. > "National borders aren't even speed bumps on the information superhighway." -- one of the few things we all share: the utter, corrosive contempt for our elected officials.

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Have at it. Username provided
by Kermit69 17 Dec '03

17 Dec '03

Hey. Try this, whitman.gmu.edu a username = myost

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Deleted Message (fwd)
by <pstira＠escape.com> 17 Dec '03

17 Dec '03

One must wonder about these military types. Hm... -millie ---------- Forwarded message ---------- Date: Sat, 7 Sep 96 16:50:21 -24000 From: MAILER-DAEMON(a)mqg-smtp3.usmc.mil To: pstira(a)escape.com Subject: Deleted Message To: "Gary Howland" <gary(a)systemics.com> From: MQG-SMTP3@USMC_MASTERINET@Servers[<pstira(a)escape.com>] Subject: Re: PRESS RELEASE: GERMANY CENSORS DUTCH WEBSITE WWW.XS4ALL.NL Message in Transport deleted by: ADMINISTRATOR@USMC_MASTERINET@Servers

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