December 2003 - cypherpunks-legacy

Linking = Showing = Transferring?
by tcmay＠got.net 17 Dec '03

17 Dec '03

I posted this to the Cyberia mailing list, but think it has some implications for Cypherpunks as well. And, I'm responding to Duncan Frissell, one of our own. (I don't advise subscribing to Cyberia unless legal issues interest you and you have the time for another high-volume mailing list. Still, some bright folks there--as well as some dullards. David Friedman just joined the list. To subscribe, send a message to listserv(a)listserv.cc.wm.edu with the message body of subscribe cyberia-l YourNameHere.) > >To:cyberia-l@warthog.cc.wm.edu >From:tcmay@got.net (Timothy C. May) >Subject:Linking = Showing = Transferring? > > >As good a chance as any to extend my "showing = telling" point... > >At 9:32 AM 9/14/95, Duncan Frissell wrote: > >>And my favorite: "What if the student merely includes *links* to >>the above on his web page?" Of course racist images/messages are >>always and everywhere as legal as church on a Sunday although they >>may carry civil liability in limited cases -- not a problem for >>judgment-proof students. >... >>"Is the URL the page itself? --- Unanswered philosophical questions >>of the wired age." > >_Linking_ is effectively _showing_, given the point-and-click mechanics of >hypertext. This is a situation anticipated by authors (e.g. Ted Nelson), >but is now coming to the fore. > >Granted, providing a link is not the same as actually _including_ the >material the link points to, but it is very, very close. Arguably, the >same. > >(Example: I create a home page with links to many images that are child >pornography by U.S. standards. The images themselves may be initially >stored in URLs that are in countries with different standards for consent, >e.g., Denmark or Thailand. Have I violated the child porn laws? Arguably, >I am "making available" these materials, but all I have done is to provide >the _pointers_. The readers of my home page are the actual downloaders, >not me.) > >I can imagine rebuttals to this position, arguing that an author who >includes URLs to other places is doing nothing different than an author >who includes footnoted references to other works (and surely we all agree >that footnotes are not copyright infringements of any sort). > >However, look at how the Web is being used. Home pages that have >compilations of interesting things are effectively the works! It is as if >the original materials are being stored on those home pages themselves! > >There is _technological_ and _propertarian_ fix to this: controlled or >paid access to the URLs under question. The "gatekeeper" function shifts >to the actual material under question. > >But there are many new questions. > >And Duncan's specific point remains: > >-- is it a violation of pornography laws (perhaps campus rules) to have a >home page with links to URLs containing pornographic images? > >-- is it a violation of _child pornography_ laws to have a home page with >links to URLs containing child pornography images? (The URLs could be >offshore, perhaps in jurisdictions where the age of consent is much >different than in the U.S., e.g., Denmark or Thailand.) > >-- is it a violation of national security laws to have a home page with >links to URLs containing national defense secrets? (The URLs could be >offshore.) > >-- is it a violation of copyright/patent laws to have home pages with >pointers to protected material? (Songs, written works, images, inventions, >etc.) > >And so on.... > >--Tim May ---------:---------:---------:---------:---------:---------:---------:---- Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay(a)got.net 408-728-0152 | anonymous networks, digital pseudonyms, zero Corralitos, CA | knowledge, reputations, information markets, Higher Power: 2^756839 | black markets, collapse of governments. "National borders are just speed bumps on the information superhighway."

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Child Porn, Morphing, and Pointers
by tcmay＠got.net 17 Dec '03

17 Dec '03

At 2:40 PM 9/14/95, Rev. Ben wrote: >> The bill would expand the definition of child pornography >> to include any photograph, film, videotape or computer >> image produced by any means, including electronically by >> computer, if it depicts or appears to depict a minor >> engaging in sexually explicit conduct. > >If I'm reading this correctly, if I Photoshop a kids face onto the body >of the latest Playboy centerfold, I'm in violation of this proposed law? I believe there have already been prosecutions along these lines. For example, do you think a _comic book_ with child porn themes ("explicit" art, situations) would not be prosecuted as child porn? I strongly suspect that a _painting_ of a 7-year-old girl engaged in a sex act would result in a prosecution. Keith Henson, amongst others, has long suggested that a good test case will be the _morphing_ of legal images to make them look like child porn. This is not a legal list--for that there are several other fora/forums--but it is clear that the child porn laws are not necessarily aimed at the protection of specific minor children from "exploitation," as the laws apply to porn imported from countries where the age of consent is lower, apply to images of dead children (who can no longer be exploited by the images), and to "created" images of children (morphing, cut-and-paste, paintings, etc.) The laws are clearly aimed at both extinguishing the _market_ for child pornography and the _thoughts_ themselves, not at the protection of specific children. (Advocates will argue that by suppressing the production of child porn markets, future children may be protected....) The main Cypherpunks theme I can find here is this: anonymous remailers and Web proxies will be used to access offshore (or indeterminately located) sites. The Feds will likely come down very hard on any remailers or proxies found to be "trafficking" in such materials. I'm going to post to this list a recent post I made to the Cyberia list about whether pointers are the same as transfers. --Tim May ---------:---------:---------:---------:---------:---------:---------:---- Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay(a)got.net 408-728-0152 | anonymous networks, digital pseudonyms, zero Corralitos, CA | knowledge, reputations, information markets, Higher Power: 2^756839 | black markets, collapse of governments. "National borders are just speed bumps on the information superhighway."

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Annonymous Web proxies.
by hallam＠w3.org 17 Dec '03

17 Dec '03

There has been a lot of debate about setting up of annonymous Web proxies. There are many thousand already deployed. Any Web proxy which does not keep logs is effectively an annonymous Web proxy. Just download the CERN server and run it. http://www.w3.org/hypertext/WWW/Daemon/Status.html The point about monitoring such sites is an apt one. Iwork under the assumption that I am monitored because if I was a spook I would be monitoring me. Most of the discoveries of security holes arrive at my door sooner rather than later. I would have monitored the communist party for the same reason, it was one of the the most obvious place for the soviets to attempt infiltration, the other being the authoritarian establishment right. Phill

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MIME Security Issues
by Richard Potocki 17 Dec '03

17 Dec '03

Does anybody wish to express any comments regarding MIME security. I have read the RFC's and any/all doc's I could find on this issue. I understand what the security risks are, but I have been unsuccessful in my attempts to find info regarding what is being done, or has been done to correct this. If I remember correctly, I think I once saw a brief mention of filters or something. I am new to this stuff, so any assistance would greatly appreciated. Thank you, Rick

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Re: why ecash is traceable
by tcmay＠got.net 17 Dec '03

17 Dec '03

At 10:49 PM 9/15/95, Nick Szabo wrote: >Hal & Tim have made some interesting comments about payee untraceability. >I suspect it will clarify things to point out the orthogonality in >two of the major design choices: > >* Clearing: Offline vs. online >* Settlement: Deposit to payee's account vs. sending new cash to payee > >Because DigiCash wants their product to have payer, but not payee, privacy, >the current ecash(tm) software from DigiCash uses online clearing >and deposit to payee's account, but the three other combinations are >also quite doable if somebody wanted to implement them. The design that >allows symmetric untraceability combines online clearing with sending new >cash. This way the bank need not ID the payee Bob in order to credit Thanks, Nick, for summarizing this clearly in terms of these two axes. This symmetric untraceability is what I was getting at with my point about Bob clearing the transaction and getting back blinded cash. It's apparent that if Alice can get untraceable cash, and she tells her bank to go ahead and give the same kind of untraceable cash to Bob, then Bob can also get untraceable cash. .... >Offline clearing requires the potential to ID the payer in >order to punish double-spending after the fact. Offline clearing has many hurdles to overcome, and this "True Name" (ID) issue is not very attractive. Fortunately, the vast increases in Net speeds are on the side of online clearing, even for relatively small transactions. >Online systems without observers (such as ecash(tm)) don't >need to worry about trying to find multiple spenders, because this is >prevented by the online clearing. In fact, purposeful second-spending >is used to recover from some error conditions, specifically to determine >whether the payee in fact received the "coin" or not when there has been a >network error in the middle of a transaction. Distinguishing between >mistaken and fraudulent double spending is a very complex, not completely >tractable problem, so the current ecash(tm) punts it, which is reasonable >because it is online. An offline system would need an elaborate Sounds pretty compelling to me to concentrate on online clearing systems.... I can imagine limited needs for offline clearing, such as road toll systems, or parking tokens, etc. The amounts of money there can be somewhat limited, and the implications of double spending revealing identity are less serious. (Though I can imagine a worrisome scenario where a highway toll system "deliberately double spends" received tokens to track motorists...there may be precautions built into such systems that I just don't know about.) --Tim May ---------:---------:---------:---------:---------:---------:---------:---- Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay(a)got.net 408-728-0152 | anonymous networks, digital pseudonyms, zero Corralitos, CA | knowledge, reputations, information markets, Higher Power: 2^756839 | black markets, collapse of governments. "National borders are just speed bumps on the information superhighway."

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Re: your mail Re: on anonymity, identity, reputation, and spoofing
by nobody＠alumni.cco.caltech.edu 17 Dec '03

17 Dec '03

I do sympathize with L. Detweiler's concern about multiple identities. Human nature being what it is, if a series of posts appears quickly taking one view, people who disagree may think, well, I guess I'm in the minority on this, I won't make a stink about it. That's just part of the herd instinct, which, IMO, we all share. The lesson is that it is even more important on the net not to be afraid to take unpopular stands. You may find that there are more people who agree with you than you thought. In particular, although I think Detweiler's posts could be tightened up considerably, and I don't agree with his solutions in detail, I can understand his paranoia, having shared it from time to time. There are some possible technological solutions to some of the issues raised. Chaum, in his 1985 CACM paper, describes how "credentials" can be exchanged among various pseudonyms a person may have. A credential can basically be any statement by a 3rd party about a person. It could be a statement by a college that he had a certain degree. It could be a statement by a government that he had a driver's license. It could be a statement by a business that he was an agent for that business. The credential would be given to the person, then Chaum shows how it could be re-blinded and shown under other pseudonyms. The credential can be verified, but it can't be linked to the True Name or other pseudonyms of the holder. We could think about using something like this for reputations. Take Nick's question about how a new pseudonym could get through the filters. Maybe the person posts under his real name for a while, then some respected person is willing to give him a "valued poster" credential. He can re-blind this credential and submit it with posts he starts to make under his pseudonym. People will know that the pseudonymous poster is at least potentially capable of making sense, and give his words some weight. But there will be no connection to his True Name. (Of course, this could lead occasionally to a Dr. Jekyll who makes sensible and weighty posts under his own name, while under his Mr. Hyde pseudonym he rants and raves. But hopefully this would not happen too often.) Other credentials could be related to some of the other points Detweiler raised, such as list membership > some number of months. The point would be that these credentials are voluntary, used to get past people's filters, and that they retain poster anonymity while giving readers useful information about the poster. It's ironic that L. Detweiler, who has played a major part in spreading awareness of Cypherpunks technology through his widely read Privacy and Anonymity FAQ, is suggesting that people should be limited in their use of this technology. Still, the concerns he raises are going to be shared by many people, and we should try to be ready with technological solutions that are consistent with privacy protection. Hal Finney hfinney(a)shell.portal.com

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Re: CYPHERPUNK harmful. THE TRUTH IS TOLD
by Bill Stewart 17 Dec '03

17 Dec '03

>Hmmmm... If memory serves, a year or so ago there was just such a schism >when a prominent cypherpunk split off and formed the "cypherWONKS" list. :-) :-) And starting a new list lets us decided on a new LOGO to replace that old tacky rose-and-bits thingy :-) Cryptographic Professionals for Social Responsibility Cryptographic Industry Association National Steganography Alliance Cryptographers for Foreign Reflexivity Extremely Private Institute for Cryptography NII Institute of Cryptography American Cryptographic Legal Union Free Banking Institute Cryptographic Defense Taskforce Cryptographic Organization for Privacy and Security Entropy, Steganography, and Cryptography Research Organization for Women (If anything, what we need is a way to separate the technical/mathematical discussions from rants like this, but any time we get the list focused on mostly technical issues, the government goes out of its way to do something egregiously stupid or offensive...) Somewhat more seriously, though, there are times that it's useful to have a more respectable-sounding organization (or at least a letterhead...), that's open to participation by members and not just directors (which has been some people's concern about the EFF, CDT, EPIC, and maybe TAP or CPSR.) If none of those are respectable/accessible/non-socialist enough for you, and the British Cryptographic Privacy Association (or whatever their name was) can't be found or sounds too much like International Outside Agitators, and the various academic groups are too busy being academicly respectable to do political agitation ("CryptoAcademics Write Papers!"), then come up with a name and a Postscript letterhead, and start an email list that you can gateway to cypherpunks (as long as you can prevent duplications or mail-floods.) If the main goal is to have a calmer name and mostly the same activities, an alter-ego mailing list is one approach. #--- # Bill Stewart, Freelance Information Architect, stewarts(a)ix.netcom.com # Phone +1-510-247-0664 Pager/Voicemail 1-408-787-1281 #---

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RE: Mixmaster status
by loki＠obscura.com 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- I apologize for being so terse in my first message. This is not a red herring. The organization that has approached me is very pro-privacy and anonymity. I see nothing but good coming from this venture. I will be very active in the development of the commercial version of Mixmaster. Let me be crystal clear. 1) I will not support any version of Mixmaster that is weakened. 2) All future clients will be able to generate the current message format. 3) All future servers will be able to read the current message format. 4) There will always be a free version of the client with source code. While I have not discussed it, I can not imagine that there would not also be a free version of the server code (with source). Without remailers what is the point of the client software? At 8:45 PM 9/14/95, ROBO Mixmaster Remailer wrote: >Flame Remailer <remailer(a)flame.alias.net> wrote: > >> Subject: Mixmaster status >> >> There has been an offer to purchase and commercially develop Mixmaster. >> This will hasten the development of Mixmaster for other platforms (e.g. >> Dos, Windows Macintosh), and bring significant improvements to the >> interface, but I will not compromise on the level of security provided by >> Mixmaster. Free client software will continue to be available. >> >> This could be the big breakthrough for remailers, finally thrusting them >> out of the hobbyist's closet into the corporate world. >> >> I wonder. Where is the commercial market for remailers? Who has an >> application for them except hobbyinst? Why would there be a commercial >> incentive to run a mixmaster server, or even a client? >> >> Could this "offer" be a red herring? > >I wondered the same thing myself. It would certainly be a more >cost-effective way for the NSA to compromise Mixmaster technology >than by brute force. > >Consider this scenario ... Mixmaster get's bought by the Acme >Crypto Company of Ft. Meade, MD. They "improve" it, and offer a new >version. It's even FREE (for non-commerical use)! But their >"improvements" make it incompatible with previous versions, and so >you have to upgrade. The new "commercial" version comes with no >SOURCE CODE, of course... -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQEVAwUBMFkzR/Pzr81BVjMVAQH6hAf+O+QdTEzNjUh0FYlJEnCakNws4MxPrOt4 miMPaz/aWDOReGb62UPZAEMNXP+hjgy0kTjW4xReTTBAPgtcsInr1Cct6MPr3O/r PGMGmE9z2Fkv3/k7MDG1NiptT2/RwVtmDikIJEQuH5j8ijir28Vvrk9Vs685Qc3j bFz5Q8uRLd57Uk51tQwIiBM6CJ4suQ3WFN++QNTHM9E47J9W8yFBux6ePWPlZOK8 8BnKkhY/auPm85X3MVZhL3y7F6zbFuqPpZrsKpwOOkme8o4l71t2xyhGcZHHxiB7 JLF2As9pNXsKWpYiPZEHTV9hsgxQTHortdhq25DeGyoxhZSrZByP/w== =+O16 -----END PGP SIGNATURE----- ---------------------------------------------------------- Lance Cottrell loki(a)obscura.com PGP 2.6 key available by finger or server. Mixmaster, the next generation remailer, is now available! http://obscura.com/~loki/Welcome.html or FTP to obscura.com "Love is a snowmobile racing across the tundra. Suddenly it flips over, pinning you underneath. At night the ice weasels come." --Nietzsche ----------------------------------------------------------

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Re: Explaining Zero Knowledge to your children
by Karl L. Barrus 17 Dec '03

17 Dec '03

At 08:18 PM 9/14/95 +0200, you wrote: >There is a paper about explaining Zero Knowledge methods in simple >words. It's titled "Explainig Zero Knowledge Authentication to your >children" or something similar. I think you are refering to Quisquater's (sp?) explanation, which is in terms of Ali Baba and a magic cave. A functionally similar explanation is in Schneier's Applied Crypto, pp. 85-86. -- Karl L. Barrus <klbarrus(a)infocom.net>

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more number theory more number theory
by nobody＠shell.portal.com 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- > What estimates exist for the density of large Carmichael numbers, > say 1000 bits long? I'm not sure off hand - maybe Ray can try to check the source of his formula. Carmichael numbers must be square free and the product of at least three primes... I seem to remember a formula for the distribution of square free integers, but can't quite remember it... > test? Are other probability tests like Miller-Rabin any more > provably likely to detect these? Well Phil, you are in luck! Miller-Rabin isn't fooled by Carmichael numbers. There still is a chance for failure, but it doesn't depend on the input (i.e. there are no bad inputs for Miller-Rabin like there are for pseudoprime testing). Failure depends on how many iterations you perform (n iterations = 2^-n chance of failure) and the values of the base you choose. For example, in Miller-Rabin, the Carmichael number 561 is exposed to be composite by choosing a base of 7. I'm familiar with two other primality testing algorithms (I'm no number theory wiz so there are probably more): Lucas' and Lehmer's. Well, Lehmer's method is a modification of Lucas' method. They both are slow, but have the advantage of being true. -----BEGIN PGP SIGNATURE----- Version: 2.3a iQCVAgUBLaoM/IOA7OpLWtYzAQEXPQQAy1110rgCUzLtKoaTsWvGCujq3fWD7Ppz A+/2b4NmR9+YmqHl63kb9zKU1/KOfDVXsmE7o0beyRQzSNGzj2I5yEUrnz0IzBLt cy4ooiE3ED/jBBc01MBYhm5v3s9dIMJNXbsw7mBSBasqzEvHHpjH8dnGZA8QXhYT fKTlU7rKa0o= =XgrZ -----END PGP SIGNATURE-----

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