December 2003 - cypherpunks-legacy

This just in..
by owen＠autodesk.com 17 Dec '03

17 Dec '03

What an incredible coincidence, this is excerpted from the RISKS digest. LUX ./. owen ------------------------------ Date: Thu, 7 Oct 93 08:40:21 -0700 >>From: Tom Hanrahan <hanrahan(a)sequent.com> Subject: Epitope suit uses computer bulletin board >>From The Oregonian (Portland, Oregon), October 7, 1993, by Vince Kohler Epitope Inc. used information subpoenaed from the computer bulletin- board service Prodigy to prepare a $5 million federal lawsuit against a Kidder, Peabody vice president in Kansas City, Mo. Lois Rosenbaum, a lawyer for Epitope, said the company used information from Prodigy Services Co. to track down A. Karl Kipke, who works for Kidder, Peabody in Kansas City, Mo. The lawsuit claims that Kipke used a false name, William Smith, to log onto a Prodigy electronic bulletin board on three occasions in August. Each time, the lawsuit contends, Kipke wrote lengthy commentaries he knew were false and defamatory about Epitope, the company's management practices and its attempts to gain federal approval of an oral device used to detect the AIDS virus. [...] "We certainly believe the price of the stock is lower than it would've been but for these false allegations, Rosenbaum said. "And I think it's clear that the articles were written for the purpose of negatively influencing the price of the stock." [...] Epitope's lawsuit says Kipke and his clients were holders of short positions in Epitope stock. [...] Epitope's lawsuit seeks $5 million in punitive damages from Kipke and alleges defamation, manipulation of security prices, securities fraud and intentional interference with business relations. Rosenbaum acknowledged that the lawsuit's electronic dimension is "a very unusual situation." Submitter note: The omitted sections of text basically say that Kipke was unavailable for comment and explain what holding a "short position" means. -- Tom Hanrahan, hanrahan(a)sequent.com ------------------------------

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Radio, Radio...
by Peter Wayner 17 Dec '03

17 Dec '03

I thought it was interesting that people on this net are getting interested in placing a discrete network of spread-spectrum boxes around the area. It turns out that a company, Tetherless Access Limited, is just beginning plans to do this right now. Here is a press release I just got: -Peter

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Sorry about that last message
by Peter Wayner 17 Dec '03

17 Dec '03

I didn't mean to append that note about Moscow at the end of the press release. It happened by mistake. You can enjoy it but please delete it afterwards. I've gotten about three copies in the mail through different forwarding paths. -Peter

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Re: The death of the list as we know it (tm)
by Matthew B. Landry 17 Dec '03

17 Dec '03

>We debate this issue every couple of months. Give it up. Or start your >own newsgroup. I'm strongly thinking of doing that. However, I think it would be a shame if we had to operate the newsgroup and the list in paralell, without connections. And frankly, I don't think it would be entirely a disadvantage to have wider exposure. Sure, we would get some more noise (but we're used to noise by now), but we would also get a much larger readership. We would still be preaching to the choir, but we would have a "choir" large enough that it would no longer be a disadvantage. As a compromise solution, perhaps we could have a one-way gateway to a general distribution newsgroup, where posts to the list would automatically go to the newsgroup as well, but posts to the group would only go to the group (unless the person also mailed to the list). The list.cypherpunks group at Msen (where my account was before) was set configured like a moderated group, so all posts got sent to the list, but there's no reason it _has_ to be that way. Really, I think there are ways to solve this so that everyone will get what he needs. -- Matthew B. Landry ml7694a(a)american.edu (Finally!) mbl(a)ml7694a.leonard.american.edu

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Diffie-Helman example in g++
by cman＠IO.COM 17 Dec '03

17 Dec '03

Here is a little demo using the big Integer routines from libg++ illustrating how Diffie-Hellman key exchange works. Basically, I wanted to prove to myself that it works, and thought others might appreciate it. Doug =============================================================== // Demo of mathematics for Diffie-Hellman type key exchange // // Useful to convince oneself that it really does work and that // a patent on it is pretty silly. // // Douglas Barnes (cman(a)io.com) // // Based on algorithm from Cryptography and Data Security, by Dorothy E. // Denning, 1983, Addison-Wesley. // // Note: you will need to have GNU libg++, or hack it to use big integer // math you do have. #include <stdlib.h> #include <time.h> #include <sys/types.h> #include "Integer.h" Integer& RandBigInt(int bits); Integer& FastExp(Integer& A, Integer& B, Integer& p); #define keysize 644 main() { Integer p; Integer a; Integer XA, XB, K1, KA, KB, YA, YB, T; char state[256]; pow(2, keysize, p); p = p - 1; // Does anyone have a clue what good values of 'a' are in this // algorithm? a = 127; // Set up random stuff initstate(time(0), state, 256); cout << "A and B pick random numbers in the Galois field [0, p - 1]\n"; cout << "where p is (2^" << keysize << ") - 1:\n" << p << "\n"; XA = RandBigInt(keysize); cout << "\nA picks a random secret XA: \n" << XA << "\n"; XB = RandBigInt(keysize); cout << "\nB picks a random secret XB: \n" << XB << "\n"; YA = FastExp(a, XA, p); YB = FastExp(a, XB, p); cout << "\nA gives B a message YA (a^XA mod p): \n" << YA << "\n"; cout << "\nB gives A a message YB (a^XB mod p): \n" << YB << "\n"; KA = FastExp(YB, XA, p); cout << "\nA now knows the key is (YB^XA mod p): \n" << KA << "\n"; KB = FastExp(YA, XB, p); cout << "\nB now knows the key is (YA^XB mod p): \n" << KB << "\n"; cout << "\nComputing the key (which is a^XA^XB mod p) from (a^XA mod p) and\n"; cout << "(a^XB mod p) is equivalent to performing two discrete log calculations;\n"; cout << "the number of steps to perform discrete logs grows exponentially\n"; cout << "in proportion to the # of bits in the field. For a 'p' of 644 bits,\n"; cout << "Denning estimates 1.2 x 10^23 steps.\n"; } // Calculate a^z mod n // // Based on the fact that (a^3 mod n) is the same thing // as: (((a * a) mod n) * a) mod n // // Gets its speed from the fact that, for example, n^18 is the // same as (n^2)^9 Integer& FastExp(Integer& a, Integer& z, Integer& n) { Integer a1, z1, two; static Integer x; a1 = a; z1 = z; x = 1; two = 2; while(z1 != 0) { while((z1 % 2) == 0) { div(z1, two, z1); a1 = (a1 * a1) % n; } z1 = z1 - 1; x = (x * a1) % n; } return x; } // Yes, I know the random stuff is lame. This is a demo. Integer& RandBigInt(int bits) { int i; int randval; static Integer retval; retval = 0; for(i = 0; i<bits; i++) { retval |= (random()&01); lshift(retval, 1, retval); } return retval; }

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wireless LANs
by accom!erc%accom＠uunet.UU.NET 17 Dec '03

17 Dec '03

Well, I've got a wireless LAN up and running at home between my 486/25 and a 386 laptop - it provides uucp/cu connectivity, and I'll be adding SLIP soon. If anyone wants to see it working, let me know - I might be able to lug stuff to the next Cypherpunks meeting. I've had it running for several months now, and it was put together using all off-the-shelf compoments. The controllers cost $110 apiece, the radios are just amateur radio 2m rigs. It runs at 1200 baud, but it's enough to show that the system works, and is reliable. The controllers provide end-to-end reliable transport, so uucico doesn't have to do so much work. cu displays are a bit jerky, but *much* cleaner than on a standard voice-grade (yuck!) PacBell line here. -- Ed

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Re: The death of the list as we know it (tm)
by wcs＠anchor.ho.att.com 17 Dec '03

17 Dec '03

Another crypto newsgroup would be superfluous - we can talk technical on sci.crypt, politics on talk.politics.crypto, and get away with talking about implementation on sci.crypt, especially if sci.crypt.research gets created to provide a more pure crypto newsgroup. Yes, cypherpunks is already too high volume, but it does serve a purpose, and most of us could hack a forwarder into digesters or local newsgroups to feed our favorite newsreaders if we really wanted to.... Bill

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secure phone quest
by gtoal＠an-teallach.com 17 Dec '03

17 Dec '03

In article <9310042017.AA26812(a)fegmania.wustl.edu> you write: >vat is available from ftp.ee.lbl.gov. There's no source at the moment >but there are binaries for different architectures. (And the dynamically >linked SunOS 4.1.x versions do work for Solaris 2.x) > >vat is intended for use as a IP multicast multi-user chat program, but I >believe that it is useable for point-to-point communication also. Using >it for IP Multicast may require kernel patches (depending on your OS). There's also nevot, last seen in gaia.cs.umass.edu:~ftp/pub 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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Re: second order homophonic substitution
by hfinney＠shell.portal.com 17 Dec '03

17 Dec '03

This homophonic cypher sounds interesting. If the authorities demand your keys, you could scramble each row of the matrix (scrambling each row separately), so that only the dummy message can be recovered. Real ascii messages have a character set of about 2^6, so the actual size of the key matrix will be 2^12, and that means that each entry will be about 12 bits. For full generality in handling binary data the character set would be 2^8, meaning a matrix of size 2^16 entries with each entry being 16 bits. This is a 128K byte key, which is pretty cumbersome. Also, the cyphertext is twice as big as the plaintext, which will stand out too. Plus, once the authorities see your decryption algorithm it may be pretty obvious that it was designed for this specific purpose, and whatever pressures they applied to make you reveal the key may now be redoubled until you reveal the "real" key. A one-time-pad has the advantage that the key is the same size as the file, and there is no size expansion in encryption, plus it's a plausible approach to use for high-security encryption. It will take less space and still allows for multiple decryption. Hal hfinney(a)shell.portal.com

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Re: Standard Headers for Anonymous Remailers
by pierre＠shell.portal.com 17 Dec '03

17 Dec '03

> I wrote: > Who qualifies whom, based on what info, and to eliminate whom? > Paul mentions organizational qualification methods > Douglas defends the rights of private groups, and anonymity Yes, I meant that as a pointer to further problems. I did not mean that it is very difficult to find organizational or technical solutions (although in practice, it may very well be), nor was I lashing back at an Orwellian suggestion. (I still get caught in the way email gets read, not that I have much more luck in person :-) Even though there may be technical solutions to "limited access" groups, it is not clear how compatible each of these is with anonymity. And at the same time it will become harder and harder to figure out whether somebody is using hir Real Name or some Assumed Name. The book publishing market surprises people because an author's pseudonym is not obviously a pseudonym. Any "limited access" policy has to address the problem of pseudonyms, and of individuals offering their pseudonym for un-accredited public access. But the problem at hand is not even that... In the case of io.com, and current remailers, the problem is netnews newsgroups that don't like anonymous abuse without really understanding how hard it could be to eliminate it... Netnews, until now, is here to provide open discussion and "publishing" space. The idea of qualification can be implemented via automatic moderation for example, but it has to contend with: 1) votes by the general public, and acceptance by sysadmins who will carry the traffic (although they don't have much of a say about mailing list traffic...) 2) superset groups and cross-posting. If a "qualify"-only newsgroup is created, then a super-set newsgroup could be created that copies everyhting from the "qualified" groups, and adds open traffic. That superset still carries interesting traffic from people who shun administrative overhead. Qualified people who want to pursue the thread they started now read the superset newsgroup. 3) If you publish, and expect email responses, you need to publish your email address. That makes you vulnerable to mail bombing. It does not matter if the newsgroups carries only filtered traffic. And thanks to Owen for posting the description of some of these net.wars. It will take me a while to go through that. pierre. pierre(a)shell.portal.com

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