December 2003 - cypherpunks-legacy

Re: hohocon
by Jef Poskanzer 17 Dec '03

17 Dec '03

At Hackers 8.0 a hallway discussion (including Eric Hughes) came up with an amusing variation on these sniff-resistant authentication schemes: use a pager. It goes like this. You telnet from an insecure site to your home system, and type your userid. Instead of prompting you for a password, your system looks up your pager number, dials out to the pager service, and pages you with a random but syntactically valid phone number. Then it prompts you. You receive the page and type that number as your password. Authentication is based on physical posession of the pager, and knowing what userid/machine it corresponds to. A possible attack would be to monitor the pager frequencies and try to snag the number out of the air. Possible defense against this would be to require a special password before the page is generated - an attacker would have to monitor both the network and the radio. Not military grade security, but lots of folks have pagers and could hack together something like this in a day or so. --- Jef

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Numbered Bank Accounts (Was "privacy and rights")
by an15489＠anon.penet.fi 17 Dec '03

17 Dec '03

>> >> I hate to be the bringer of bad news, but to the best of my knowledge >> Switzerland no longer allows numbered bank accounts. Also, from >> my studies of international banking, bank secrecy and tax havens, >> I have never seen any reference to numbered bank accounts in >> any country other than Switzerland, including Liechtenstein (although >> Liechtenstein does have better secrecy safeguards than Switzerland. > >"Jack Daniels" has never looked hard enough -- many countries (Austria >comes to mind) allow completely anonymous accounts, with various >degrees of restriction on them. > "Perry Metzger" doesn't carefully read the postings which he directly quotes before passing judgement. I never claimed that nobody offers completely anonymous accounts. I claimed that, to the best of my knowledge, nobody offers the "numbered accounts" that used to be popular in Switzerland. Austria does offer "bearer share" accounts which are completely anonymous, but are quite different than the "numbered accounts" of old-time Switzerland. In a "numbered account", the owner uses a hand-written rendition of the account number as a signature. The hand-written number is compared against bank records to validate the authenticity of the owner. "Bearer share" accounts, which are available in Austria, are issued to the user with some sort of ceritificate of ownership. Anyone (the "bearer") who has possession of the certificate ("share") can withdraw money from the account. No signatures or hand-writen numbers are used to verify the owner. If Austria does offer true numbered accounts, then I stand corrected. "Jack Daniels" ------------------------------------------------------------------------- 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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CELL STRUCTURE
by Sandy 17 Dec '03

17 Dec '03

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ SANDY SANDFORT Reply to: ssandfort(a)attmail.com . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Punksters, Allan Bailey referenced "The Republic of Desire" in Gibson's /Virtual Light/. He asked: Anyone have a ref for something that discusses guerilla cell organizations? One of my all-time favorite books, Heinlein's /The Moon is a Harsh Mistress/, has a great description of how traditional guerilla cells are structured. In addition, he creates a new cell structure based on secure communications in a computer mediated setting that foreshadowed many of the concepts we deal with on this list every day. Free Luna! S a n d y >>>>>> Please send e-mail to: ssandfort(a)attmail.com <<<<<< ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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HoHoCon key exchanges
by crunch＠netcom.com 17 Dec '03

17 Dec '03

in relation to the HoHoCOn event... >> >> I am wondering if anyone I plan to bring a (cheap) laptop to I can >> collect and trade (& sign) PGP keys > John Draper has already expressed an interest in having everyone > exchange keys, and will probably mention this during his speech. > I can guarantee there will be numerous laptops, and even full > systems avaialable. Last year, we even had 4-machine internet > site going - hohocon.com. Yeah, it was great for about 5 minutes > until all the power in the wing went out. Yes... And lets have at least SOMEONE who can have a Mac at HoHoCon this time.... Last time there was NOBODY that had one. Yukk!! whatta bummer.... I am also interested if there is any rave taking place on the weekend of the HoHoCon. I sure want to get in some dancing while I'm there :-) .... CC

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Re: All our eggs in one basket?
by jim＠bilbo.suite.com 17 Dec '03

17 Dec '03

> What would happen if your bank suddenly told you that it had no proof that > you really had an account there? > > Wonderer > Theoretically, this problem is prevented by using protocols that incorporate non-repudiation mechanisms. The bank wound not be able to make such a claim. Or, another way of saying it, were the bank to make such a claim, you would be able to prove them wrong. However, proving them wrong while also retaining your anonymity may be a trick. It would depend on the design of the non-repudiation mechanisms. How do you prove to a third party that someone is falsely repudiating a valid contract or transaction without revealing any information about yourself? Conversely, how do you defend yourself against false claims of repudiation without revealing any information about yourself? After all, someone might try to discover your identity by making false claims about you, and forcing you to defend yourself. (Sound familiar?) Jim_Miller(a)suite.com

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Re: HoHoCon key exchanges
by Joe Thomas 17 Dec '03

17 Dec '03

In my experience, mass key-signing on a few laptops is a waste of time. It might be a fun waste of time at a convention, but it made the one Washington Cypherpunk meeting to date kind of a drag. Far more efficient is to print up a paper certificate with your key and its fingerprint, run off a bunch of copies, and sign them. Pass them out and let people verify your credentials; everyone does a batch signing when they get some free time. Then everyone mails their key ring to a server, waits a few days, and collects all their new signatures off the same server. But, again, maybe that takes the fun out of it. To each his own... Joe

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RE: hohocon
by hfinney＠shell.portal.com 17 Dec '03

17 Dec '03

> From: Timothy Newsham <newsham(a)wiliki.eng.hawaii.edu> > > hmm.. looks like the ideal for someone to test out a dos virus that > looks for the PGP passphrase and for secret key rings and tries to > "get out alive" with them. > > Tim N. > > Coders start your engines. > Don't type your PGP passphrase on a PC owned by someone else! You don't have to use your passphrase to exchange keys. Keys can be extracted, added, etc. without the passphrase being entered. I don't see any way a virus could be spread via PGP key exchange. At best (worst) a virus could somehow attach itself to the PGP key file but it would be just passive data. It wouldn't do anything. Hal

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Duress Passwords/PINs/Combinations
by baldwin＠LAT.COM 17 Dec '03

17 Dec '03

Having a separate authentication mechanism that is used under duress is a very good idea that some existing systems already employ. I'll pass along the ones I have had contact with. From a systems point of view, it is hard to figure out exactly how the system should respond when it recognizes a duress authentication. There are competing interests as I'll explain after some examples. The safe inside the ATM machines used by BayBanks (Boston Mass) can be opened with two combinations. One combination sends an alarm to the bank via a separate phone line (not the one used to perform the ATM transaction). The alarm phone line is also connected to a conventional panic switch. A fellow I know has a central-office alarm in his home. When the alarm goes off, the office calls his house to ask if it was a false alarm. They ask for a password to verify, and no matter what password you give they say "OK, I'll log it as a false alarm." If you gave the wrong password, they call the police and notify them of a crime in progress with hostages. If no one answers the phone, they send one of their patrol cars. The challenge-response token that Attalla sells (which is a repackaging of someone else's token) supports a fixed or variable duress pin. In the fixed duress pin mode, a special PIN, usually "1111", causes the device to use a fixed different key to compute the response to the challenge. The code that authenticates the response checks for a use of the duress key if the response does not correspond to the value expected for the user's key. The variable duress PIN approach is a feature of the card where the user can set which PIN value causes the card to use the alternate key. From a software point of view, the authentication procedure returns Yes/No/Duress. Note it is possible to have a collision between a duress response and a regular response. The competing interest problem is illustrated by the following possibility: A criminal makes an ATM money-filler open the safe at gun point (the ATM repair people do not know the safe combination). The criminal says that she knows about the duress combination and threatens to shoot the kneecaps off the person if they use the duress combination. The criminal will take the money-filler hostage for a few minutes to guarantee a clean get-away. So what does the money-filler do? To use the duress combination requires faith that the bank will handle the situation in a subtle way and thus avoid major knee surgery. For the bank, why risk loosing any money or loosing the criminal. In fact, why not just refuse to open the safe in the first place? What is the right balance between these interests? How does each party trust that the other will behave as expected? What is the benefit of this approach when the criminals already know about it? It works well against criminals that don't know about it, but is that enough to justify the overhead? These questions are not show stoppers. Individual organizations can and do answer them in order to make rational choices about duress authentication. In the cases of communicating cells, the key benefit is giving the adjacent nodes time to cleanup their surroundings of evidence or to totally "leave town". --Bob

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Sorry...
by --spin＠iastate.edu-- 17 Dec '03

17 Dec '03

I am terribly sorry about the last message. The Cc: escaped my attention. I shall be more careful in the future.

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souls and Multiple Personality Disorder
by gtoal＠an-teallach.com 17 Dec '03

17 Dec '03

In article <m0ozdjZ-000HXQC@khijol> erc(a)wetware.com "Ed Carp" writes: > I thought this was rather tasteless. MP is real. My SO is MP. It's not > very funny. Do you know what causes MP? Childhood sexual abuse. Possibly, but more often overzealous psychiatrists with an axe to grind. (Let me guess, she had no history at all of MPD before she went to a psychiatrist for some unrelated problem, right?) G -- Personal mail to gtoal(a)gtoal.com (I read it in the evenings) Business mail to gtoal(a)an-teallach.com (Be careful with the spelling!) Faxes to An Teallach Limited: +44 31 662 4678 Voice: +44 31 668 1550 x212

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