December 2003 - cypherpunks-legacy

digital signatures and "meaning"
by Mark M. 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Digital signatures can have many different uses and meanings. The most popular application of digital signatures is proof of authorship. A person signs something when he claims that he wrote it and if the signature is invalid, the message must have been altered. However, digital signatures are used for many other applications. Typical applications include timestamping, digital cash, and validating a document or statement. The problem with these applications is that there must be some way to distinguish and timestamp signature from a proof of authorship. There are several different ways to do this: - Make all digital signatures prove proof of authorship. Someone would include the text of the document he wants to sign and put a message saying at the end such as: "This document existed on such and such date" or, in the case of digital cash, "This coin was blinded and signed by the bank using standard protocols." - Append some kind of electronic tag to the message that represents a certain kind of authorization. This is identical to the previous method except it relies more on protocols. - Specify the type of signing that is to be done with a key. This could be included in the text of the user-ID field of the public key in a PGP-like program. It could also be done by extending a key generation and management protocol to include a tag on the key itself specifying what this key is to be used for. There are advantages and disadvantages to each of these. The first has the advantage that it requires no protocol modification but relies on "legaleese." The second method does require that protocols be slightly modified, but these modifications could be made by just pre-processing and post-processing the message with another program. However, this is more limited than the first method because it essentially uses "canned" messages. The final method relies on either no modification to the crypto program used or a non-trivial modification. Personally, I tend to think that anything that uses a standardized protocol is a Good Thing. This is why I think that the second and third methods listed above would work better than the first. Comments? - --Mark =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= markm(a)voicenet.com | finger -l for PGP key 0xf9b22ba5 http://www.voicenet.com/~markm/ | bd24d08e3cbb53472054fa56002258d5 PGP: Because sometimes, a _Captain Midnight_ decoder ring simply isn't enough. -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: noconv iQCVAwUBMQ1agLZc+sv5siulAQFKtwP/Xs7gOm1vP2FeDJDjahymYbMum3JrFqh0 VKXrkjmlh42ygX9y2sLfivN7DMsAGIF86NRaW67x0LD2uPuBl00KyvC18bqEPfiF kMbvOZv96xL4fBssheRR7F4YH/oaASxCagxuAkIqBxi9uEzAppNloxMYHy87w0kY h+48n+YH3D0= =QTZp -----END PGP SIGNATURE-----

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Re: Lotus Notes
by Rich Salz 17 Dec '03

17 Dec '03

Thanks for the explanation -- in all my discussion with RSA and explanation to our lawyers I was thinking strictly API. Your quote of the RSAREF license says they won't refuse anythign reasonable, and one would be hard-pressed to say that changing keysize for something already not exportable isn't reasonable. I'll have to read our license when I get to work tomorrow. /r$

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The Boys From Brazil - thoughts on cloning Nazi servers
by Simon Spero 17 Dec '03

17 Dec '03

I've tried to stay out of this thread, as it is mostly off topic, but I do have one suggestion to people setting up clones of the zundel site. There's a fine line between defending someones freedom of speech, and actively promoting that speech. The reason these mirrors have been set up is to counter the restriction on access to the original site that has been put in place by Deutche Telecom; however, in addition to defeating this restriction, this approach also makes the material more widely available than it was previously, which could be seen as crossing the line between defence of free speech, and active promotion. One approach that would stop this line being crossed would be to configure the clone servers to only allow access to sites in Germany affected by the original restriction. This compromise defends freedom of speech, but does not give the site any wider promulgation than it would have had had no government restrictions been emplaced. Simon

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Re: Unscribe
by Alex de Joode 17 Dec '03

17 Dec '03

TCM sez: : At 1:34 AM 2/2/96, Ewout Meij wrote: : >unscribe cypherpunks(a)toad.com : ^^^^^^^^ : > : >unscribe emeij(a)pi.net : ^^^^^^^^ : > : >There is a theory which states that if ever anyone discovers exactly : >what the Universe is for and why it is here, it will instantly : >disappear and be replaced by something even more bizarre and : >inexplicable. : There is a theory which states that the correct way to unsubscribe from : mailing lists is defined by the mailing list charter and principles, and : that sending misspelled "unscribe" messages to the wrong place, and : including "unscribe" messages intended for other lists, is bizarre and : inexplicable. : --TCM [pi.net] 'Planet Internet' is the dutch equivalent of AOL. -AJ-

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Re: Downsizing the NSA
by dlv＠bwalk.dm.com 17 Dec '03

17 Dec '03

A semiparanoid thought struck me: Maybe the NSA doesn't these extra 20K people, they just don't want them to go out into the industry and build crypto for the outside world. So they continue to pay them salaries and have them do nothing useful. This would be kind of analogous to how when Russia no longer needed so many nuclear scientists, the U.S. helped create "make work" jobs for them, just so they wouldn't go to work for the likes of Iraq. --- Dr. Dimitri Vulis Brighton Beach Boardwalk BBS, Forest Hills, N.Y.: +1-718-261-2013, 14.4Kbps

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Re: Crypto-smart-card startup Inside Technologies
by jim bell 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- At 09:41 PM 1/31/96 -0800, Peter Monta wrote: >jim bell <jimbell(a)pacifier.com> writes: > >> > [ Inside Technologies ] >> > ..."In public-key cryptography, 512-bit keys are typical and >> > already vulnerable. So we are looking at 640-bit-long keys >> > supported by a scalable design." >> >> This kind of thing disgusts me. We already know 512-bit keys are weak. As >> I recall, I was told that 512 bit keys could be cracked in 20,000 >> MIPS-years. If the ballpark formula holds that adding 10 bits doubles the >> security, that merely means that 640 bits is 2**(128/10) or 8000 times >> strong. While obviously better than 512, it is not ENOUGH better to make me >> confident that this is a long-term secure length. 768 or 1024 bits should >> be considered the minimum. A deliberate design of 640 bits makes it look >> like it's intended to be crackable in 5-10 years, much as DES was suspected >> of a similar design decision in limiting its keylength to 56 bits. > >But the "scalable design" presumably means the hardware can deal >with a variety of modulus lengths. As you say, they would be >short-sighted to make a fixed choice. I hope you're right about this. But there's something to keep in mind. Let's suppose that in 10 years 640 bits are "easily" cracked. Anybody with the storage (money) to keep all these messages will have the power to sort through everything you said in 1996, '10 years later.' Who has the money to even store these messages, as well as the inclination? You guessed it, the government. I realize that it is arguable that this would be possible, no matter what keylength is chosen. True, someday 1024-bit keys might be easily cracked, but that will probably be 30-50 years from now, not 10. In other words, "stretching" the technology today on the "encrypt" side makes storing these messages far less attractive, meaning that the government will have less motivation to do it, and will not be able to make the effort pay off for a few more decades. I would like to see laws: 1. Prohibiting the government from storing encrypted messages it can't currently decrypt for over, say, a couple of years. 1a. Prohibiting any USE by the government of such messages obtained and stored by other entities, including individuals and private corporations, without the express permission of the sender AND receiver of the message. 2. Prohibiting the government from even ATTEMPTING to decrypt a domestically-obtained encrypted message, without a warrant which is simultaneously given to the source of the message: In other words, alerting him to the government's interest. This is just a start. -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQCVAwUBMREY2/qHVDBboB2dAQGZdgP+MjIK02fU6iysN77g1aWb1gx9bzDrZoh4 ePWmd9RRD3gnzYOSIng5dRCxEpT+0Cqe4cFQEqbD6GhHlfNOKwkTU/LAfhvOdKpo QJ9t93Af3aCaLtFmtXyj1Ce20GNqkp7qqP5DLKjYSEH/bR64aTA0pfZ70aes/8C1 w1AYLdvglXA= =p+3A -----END PGP SIGNATURE-----

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American Banker article on First Virtual
by Thomas C. Allard 17 Dec '03

17 Dec '03

PGP message

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DSN
by Laszlo Vecsey 17 Dec '03

17 Dec '03

Anyone heard of DSN? I think thats the right order of the initials... ... its supposedly the only crypto-hardware solution for protecting an entire network on the Internet. You put one of these $5,000 units at one end of a lan, and another one somewhere else on the Internet, and the company gaurantees secure, encrypted transmissions. The TCP/IP headers and data are mangled, encrypted, etc. It uses 512bit keys and I was just wondering how the authentication is done. Does anyone have any specs on these units? Supposedly it does not require a 3rd party entity to verify that the two units are both valid, when determining the initial public/key pairs. Perhaps there is hardcoded data in the units that is used to verify this? The company supposedly has some proprierty method ... how can we be sure this expensive unit can do its job if information on the encryption has not been released. Is there any freeware software solution that has been put through more of a torture test, and proven to work? It seems to be the best approach would be to put such a program on a server that is acting as the gateway/firewall on each network. (define(RSA m e n)(list->string(u(r(s(string->list m))e n))))(define(u a)(if(> a 0)(cons(integer->char(modulo a 256))(u(quotient a 256)))'()))(define(s a)(if (null? a)0(+(char->integer(car a))(* 256(s(cdr a))))))(define(r a x n)(cond((= 0 x)1)((even? x)(modulo(expt(r a(/ x 2)n)2)n))(#t(modulo(* a(r a(1- x)n))n)))) "SGI and Linux both run Motif and X11. They both compile c++ cleanly (using gnu g++). They're the same!"

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Unscribe
by Ewout Meij 17 Dec '03

17 Dec '03

unscribe cypherpunks(a)toad.com unscribe emeij(a)pi.net There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another which states that this has already happened on 02/01/96

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The Boys From Brazil - cloning Nazi servers
by mpd＠netcom.com 17 Dec '03

17 Dec '03

ses(a)tipper.oit.unc.edu (Simon Spero) writes: > There's a fine line between defending someones freedom of > speech, and actively promoting that speech. The reason these > mirrors have been set up is to counter the restriction on > access to the original site that has been put in place by > Deutche Telecom; however, in addition to defeating this > restriction, this approach also makes the material more > widely available than it was previously, which could be seen > as crossing the line between defence of free speech, and > active promotion. I think you have to look at the balance between two things. First, there is the effect of making the material more widely available and publicized than it was prior to the attempted censorship. This effect is definitely real. Indeed, prior to a few days ago, I wouldn't have known a Zundelsite from a hole in the ground. Second, however, is the unprecedented opportunity for people running mirrors to guarantee that large numbers of the public will encounter said material for the first time enveloped within their chosen "context wrapper." Now it is well known that the crafty art of propaganda rarely consists of deliberate falsehoods, like "yellow rain" or "spy dust". It mostly consists of making sure one is in complete control of the circumstances in which potentially damaging information is disclosed. The opportunity to present Mr. Zundel's views brightly gift-wrapped in paper bearing the legend - "Here are the offensive views of a hate-mongering Nazi whose victims are supporting his right to be heard" - is worth more than a thousand press releases denouncing Mr. Zundel by the anti-defamation brigade. I would expect that it is this second effect which predominates, and therefore the proliferation of mirror sites is in fact a victory for Mr. Zundel's detractors, and not a promotion of Mr. Zundel's views. -- Mike Duvos $ PGP 2.6 Public Key available $ mpd(a)netcom.com $ via Finger. $

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