- cypherpunks-legacy - lists.cpunks.org

Re: NetScape's dependence upon RSA down for the count!
by Bill Stewart 17 Dec '03

17 Dec '03

>What you have described is the classic 'man in the middle' attack. >Netscape claims that SSL V.3 is immune to the MITM attack in >appendix D.4 of the SSL V.3 spec. > >You will need to get the 'filter' (MITM) key signed by Verisign. >Or hack Verisign's server-key-signing key. Or hack the Web of Trust used to verify the server's identity. It _is_ still a Web of Trust even if it's a fascistly-hierarchical tree; as long as it's possible to get a certificate without heavy contractual obligations, you can hack it, since the software has no way to check, now that Netscape is being nice and open and allowing non-Verisign certs. Remember that anybody can be a CA, and keys can be signed by multiple CAs. Verisign Business CA signs Carol's Certification Consultants' key. Carol signs Bob's Better Browser Business's key. Bob runs a server, selling really cool web tools. Verisign Business CA signs Moriarty's Mallet Makers' key. Moriarty signs Mr. X's personna key (trust us.) Mr. X makes a key called Bob's Better Browser Business, looking suspiciously like the real thing, only it's signed by M . X, and nobody bothered telling Bob about it. Alice, using Netscape, encounter's http://www.Bob'sBetterBrowser.com/, and decides to order a Better Browser. She gets Bob's public key and X.509 certificates by pressing a button, and receives a key and a pile of certs. Since it's not a secure session yet, is Mr. X intercepting them and sending her _his_ key and cert for "Bob" and his personna key with cert from Moriarty and his key and cert from Verisign? So Mr. X rips off Alice and/or Bob somewhere here, and Alice decides to sue Bob, who says "Hey, that's not my key, see my real set of certs", so they go off after Mr. X, who they can't find, and then go after Moriarty, who says "Hey, it's just a personna certificate; all I guaranteed was that I didn't sign more than one with the same name on it", which in fact appears to be true, and while after one case you can't be sure that there really wasn't a Mr. X somewhere, if three or four people start walking in saying Mr. X ripped them off using a key that Moriarty signed, maybe somebody'll think it's a movement... And remember that if you can finesse a signature, you can fake a Diffie-Hellman session with authenticated keyparts into tolerating your MITM attack, because you can convince Alice's browser into accepting the fake key for Bob, and as far as Bob knows, Alice is just another web-client that he doesn't know from Adam. Now, X.509 certs don't limit themselves to hierarchical or Web use, and most advice on using them recommends limiting the depth of a tree/web that you're willing to trust. Unfortunately, X.509 certs don't even have a comment field, much less a standardized "how much do you trust this person you're signing" field, though I suppose you can cram a bit into the X.400/500-style name formats. So if people want to really trust their digital signature system to prevent forgeries, then either there's got to be a law demanding lots of government- approved is-a-person nationalized ID card Internet Driver's License stuff, or else there's a market need for companies providing heavy-duty contractual backing for their key signatures (e.g. "In return for us signing your CA key with our high-trust CA key, you agree to accept $XM of liability for any misuse of keys you sign with it and to force anybody whose key you sign to also sign a contract like this one"). Probably a need for some standards to go with it. There's also a need for browsers and any associated certificate checkers to provide good user interfaces (so the _user_ can read the signature chain) and good tools to help the user decide what to trust. At minimum, the user interface probably should support things like different required amounts of trust for different categories of communication, e.g. business vs. personal letters vs. politics vs. smuggling. [This whole posting has been very annoying to write; I've just gone and argued that you can munge an X.509 hierarchy back into the Web of Trust and avoid the special-case treatment of Very Important CAs by just signing the top nodes of a hierarchy yourself and treating them like any other web-of-trust chain, and been thanking Netscape for allowing us to use open protocols instead of depending on Big Organizational Infrastructures that are run by the CON, and now I find myself posting a counter-example that says sometimes you have to be very careful and/or reinvent Bigness to avoid getting ripped off. But, hey, while it's not a demonstated hack, it's at least the theory for pulling one off, so even if it doesn't get me a T-shirt, at least it wins me a GIF of one :-) ] #--- # Thanks; Bill # 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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for perl experts: brclient problem
by Lou Poppler 17 Dec '03

17 Dec '03

I sent this originally only to Piete, but as I suspect he is already somewhat busy, I am now also forwarding a copy to the list. I just upgraded to brclient version 0.16. I tried to use it with this command: brclient -Ltssl -a'2977 6284 390a 3 no' I got this result: Use of uninitialized variable at ./brclient line 457, <COMMAND> line 1. Failed: 0 <No DATA> I am totally perl.clueless, so I merely refer this to you. :::::::::::::::::::::::::::::::::::::: :: Lou Poppler <lwp(a)mail.msen.com> :: No animals were harmed in the :: http://www.msen.com/~lwp/ :: production of this message. ::::::::::::::::::::::::::::::::::::::

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macworld crypto articles
by steven ryan 17 Dec '03

17 Dec '03

The current (11/95) issue of MACWORLD magazine has two good crypto articles in it. 1 - Protect your E-Mail by Bruce Schneier Good introduction for neophytes, the basic how and why. Get some reprints and give them away with PGP to your nonCypherpunk computer friends. 2 - False Security by Gene Steinberg They searched for an applications programmer *UN*skilled at cryptography to try and crack the password protection of the 8 best selling Mac programs. Quicken 5.0 was cracked in 5 minutes. Adobe Acrobat in 2 hours. Steven Ryan sryan(a)reading.com

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Re: rejection of CJR
by Peter D. Junger 17 Dec '03

17 Dec '03

I happened to speak to Mr. Capilino at the Office of Defense Trade Controls this morning, and mentioned that the Commodity Jurisdiction Request for the T-Shirt had been returned and read him the message to that effect. He told me that that was the wrong address for mail, since it was used only for currier deliveries, and that they have stopped accepting even currier deliveries there since the Oklahoma city bombing. He suggested that those who want to apply for the Commodity Jurisdiction determination should call him at 703-875-7396. He will fax the current information on how to submit a CJR to anyone upon request. He did not say so, but I rather think he looks forward to getting the T-Shirt request. -- Peter D. Junger--Case Western Reserve University Law School--Cleveland, OH Internet: junger(a)pdj2-ra.f-remote.cwru.edu junger(a)samsara.law.cwru.edu

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Usenet: pseudonymity's killer app
by pjm＠ionia.engr.sgi.com 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Risks Digest 17.42 contains a Boston Globe story by Simson L. Garfinkel detailing the risks of the DejaNews (http://dejanew.com) Usenet archiving service. Not only does this service archive Usenet postings, it provides a "sophisticated system for retrieving 'author profiles' of the individuals who have posted messages." Many people are upset at what they view as an invasion of privacy. The article notes that: > But Usenet has actually been archived for a long time. Many schools, > for example, have backup tapes containing Usenet messages dating back > many years. Furthermore, says Madere, the National Security Agency and > possibly other law enforcement or intelligence organizations has been > cross-referencing and indexing Usenet for quite some time. "I know for > a fact that they do have a text retrieval database which contains > Usenet," says Madere. Creating a searchable index of Usenet " was > already done for what people might consider to be sinister purposes," > says Madere. "What we have done is made it searchable for useful > purposes." DejaNews will be archiving the alt, talk, and soc groups beginning later this year. That could result in many more people becoming upset at the service. It would appear that ISPs could make money from offering anonymous or pseudonymous accounts to their customers who would rather not have their postings used by marketers, employers, or neighbors. Providing protection from junk mailers is also more politically defensible in this society than providing protection from the government. This could be the catalyst for widely used and accepted pseudonymity on the net. Patrick May -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQCVAwUBMI/tze5Yg08fDKehAQHUiwP/ePOJeQ5+R0+h0QQVJEziWFZvz0qCMooA 6jQXjDxWpxydas+KYCe9dt2yekjsh3Lr/bc+VHDtuTuE4l+m3HIFqk7uWxYk7iB6 fjIhuPMcmVSIg+lPOTFIlhfypmwE/6c4FHXiGb6N02Pc5E22BJFjECOdx1RNlJwv A8DbV/lAyGI= =FjnE -----END PGP SIGNATURE-----

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Diane Rehm Show just ended
by Carl Ellison 17 Dec '03

17 Dec '03

You just finished a show on terrorism (WAMU, 10-11am, 10/26/95). Thank you. Some of your callers said most of what I would have said and I found that pleasing, since I wasn't able to call in. However, there was a theme which kept coming up and which wasn't addressed specifically. You might hold it in mind for future shows on terrorism: The FBI representative was saying that the goal is to *prevent* terrorism, not just to investigate and prosecute crimes after the fact. I heard Director Freeh (on 10/19 on All Things Considered) say something similar -- that the FBI's job was to protect the people (which can be be translated into "prevent terrorism"). This seems to be a major problem and perhaps the source of the concern about civil liberties. Terrorism might be a product of an organized, identified group and infiltration of that group might enable the FBI to prevent acts of violence. Of course, the permission to infiltrate suspicious groups has been used in the past to justify infiltration of non-violent but unpopular groups like the Sanctuary Movement. However, many of our recent terrorist acts appear to be the result of individual actions -- not those of organized groups. [Unabomber, OK City, train derailment] Infiltration is out of the question in such cases. The only way to prevent such acts is to put the entire population of the US under surveillance -- an authentic instance of Big Brother from 1984. The conclusion to me is that we can not task the FBI with the job of prevention of terrorism. I suspect that we must insure that the FBI is formally and carefully restricted to the job of investigating and prosecuting crimes once they occur -- allowing the threat of almost certain prosecution to serve as a prevention -- rather than with the impossible job of prevention of such crimes. ------------------------------ Meanwhile, there was one question I had that no one answered: I didn't like history much as a student, but I vaguely remember other periods of domestic terrorism: bombings in the early 1900s, acts of violence associated with the labor movement, sabotage during WW-I conducted by German agents. There may have been many others. This seems to be a feature of life -- nothing recent, nothing special, frightening from its news coverage but not a serious threat to any one individual (because of the actual statistics around the threat -- comparing my chance of injury due to auto accident, plane flight or terrorist act (for example)). It would be interesting to know why we had the pause in terrorism during the Cold War -- or, for that matter, if we actually did. Could it be that the apparent return of terrorism is actually a perception rather than a fact -- as a result of shift in focus of the news media? - Carl +--------------------------------------------------------------------------+ |Carl M. Ellison cme(a)acm.org http://www.clark.net/pub/cme | |PGP: E0414C79B5AF36750217BC1A57386478 & 61E2DE7FCB9D7984E9C8048BA63221A2 | | ``Officer, officer, arrest that man! He's whistling a dirty song.'' | +---------------------------------------------- Jean Ellison (aka Mother) -+

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MD5 and ITAR questions
by Simon Spero 17 Dec '03

17 Dec '03

I can't remember the exact details, so could someone give me a quick refresher- which of the following are considered ok under ITAR? MD5 as a checksum keyed MD5 for authentication keyed MD5 as a stream cypher Thanks Simon --- (defun modexpt (x y n) "computes (x^y) mod n" (cond ((= y 0) 1) ((= y 1) (mod x n)) ((evenp y) (mod (expt (modexpt x (/ y 2) n) 2) n)) (t (mod (* x (modexpt x (1- y) n)) n))))

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Hello
by Xavier Naveira 17 Dec '03

17 Dec '03

Hello!!!!

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Cypherpunks Lite
by hshubs＠BIX.com 17 Dec '03

17 Dec '03

Would the person who does this, or someone who can point me at him, contact me via e-mail please?

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Re: Need a "warning" graphic of some kind for CDA
by tomservo＠access.digex.net 17 Dec '03

17 Dec '03

>At 01:48 PM 2/4/96 EST, Greg Broiles wrote: >How about the circle-slash "no" symbol superimposed on the Constitution? Hmm, I kind of went the other way. I have a gif of a baby carriage in the standard red circle and slash. Anyone who wants it, feel free to use it. Resize it, reshape it, share it with your friends. (I feel much better about buying all that clip art now.) It's at: http://www.access.digex.net/~tomservo/gif/no_kids.gif Other suggestions? Feel free to e-mail me. I'll dig up what I can. (Next up: the "PGP-friendly" logo. . .) Scott -- Scott Fabbri tomservo(a)access.digex.net Later. Later. I'm watching hockey. Finger for PGP key.

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