December 2003 - cypherpunks-legacy

Re: More FUD from First Virtual
by jim bell 17 Dec '03

17 Dec '03

At 06:51 AM 12/8/95 -0500, you wrote: >Excerpts from mail.limbo: 7-Dec-95 More FUD from First Virtual Douglas >Barnes@communiti (1157*) > >I *am* skeptical about the extent to which anonymous cash *can* succeed, What can stop it? What should stop it? >but in point of fact I'd like to help. I think society will be better >off if one of the payment options is truly anonymous. I think that >level of privacy will inevitably carry a high surcharge, however, for >reasons that I keep pointing out and you keep ignoring. Well, maybe I haven't been following those reasons, but I see little or no reason privacy should "inevitably carry a high surcharge." If the relevant encryptions had to be carried out with a pencil and a piece of paper, that claim would make sense, but remember, we've got MICROPROCESSORS on our side! I agree, I suppose, that there are definitely entities (read: governments) which would WANT to prevent the use of anonymous cash, but I view them more of an obstacle to be removed than a permanent bar.

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MAG_got
by John Young 17 Dec '03

17 Dec '03

The NYPaper Sunday Mag 12-10-95 has a longish soft-hitter by Tim Weiner about the CIA's never-say-die Deutch-uncle's CPR-wheezing the wormy carcass. MAG_got

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.PWL spin
by Joel McNamara 17 Dec '03

17 Dec '03

The Seattle Times has a rather large article this morning (12/9/95) about Microsoft's .PWL encryption weakness. Selected quotes are provided for your entertainment and enlightenment (give yourself one point for each piece of inaccurate/incomplete information or spin you can find). Security flaw in Windows 95 to be fixed Microsoft got word of the flaw from an Internet e-mail exchange last week that included a short computer program for "hacking," or decrypting, passwords contained in .pwl (password list) files. The company immediately began working on a fix. "We wanted to be proactive on this before it became a problem," said Rob Bennett, Windows 95 product manager. The company has received no customer complaints related to the issue and knows of no security breaches, Bennett said. "There are people out there who will stay up all night cranking out code to break any encryption," Bennett said. (This was followed by some good quotes from Frank Stevenson, who wrote the cracking code, on the seriousness of the weakness. I was a little surprised to see the reporter listed Frank's e-mail address in the article. Frank, if you're reading this, did you give Paul Andrews permission? To me, this seems like listing someone's telephone number and address in the body of an article.) Microsoft said it plans to strengthen the encryption, Bennett said. Password data will be stored randomly, making it harder to find on the computer, he added. Microsoft recommends that information-systems directors disable password storage until the fix is released. One system administrator said the problem would have a greater effect on less-secure environments, such as universities and other institutions, than on corporations.

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DC Cypherpunks Meeting, Dec 16. 3:00 PM
by Pat Farrell 17 Dec '03

17 Dec '03

Just a quick note: the next DC Cypherpunks meeting will be December 16, starting at 3:00 PM, location: Digex Headquarters, Greenbelt MD. See my dccp page for detail, instructions, etc. http://www.isse.gmu.edu/~pfarrell/dccp/index.html Agenda: 1) Discussion of NIST Dec 5 GAK meeting 2) The web of trust is dead, lets invent another 3) ... suggestions welcome Pat Pat Farrell Grad Student http://www.isse.gmu.edu/students/pfarrell Info. Systems & Software Engineering, George Mason University, Fairfax, VA PGP key available on homepage #include <standard.disclaimer>

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Diffie-Hellman with Blowfish
by Kent Briggs 17 Dec '03

17 Dec '03

I am working on a program that will use Diffie-Hellman with Blowfish to create a public-key encryption system similar to the way PGP uses RSA and IDEA. This system would not have the digital signature feature that PGP has, however. I invite comments on any security problems that I might have overlooked. Bruce Schneier briefly mentions this idea on p. 515 of Applied Cryptography (2nd ed): Key Exchange Without Exchanging Keys. Key Generation -------------- First, users select a private key passphrase. The passphrase is case sensitive and from 8 to 50 characters in length. A random 32-bit salt is generated from timed keystrokes. The salt is appended to the passphrase and run through an SHA-1 hash. The output is a 160-bit value, x. The 1024-bit public key "y" is calculated: y = g^x mod p (^ denotes exponentiation) p is a 1024-bit strong prime constant that does not change. g is the generator for that prime and is always 2. The KeyID for the public key is the 32-bit salt. The user publishes the public key and KeyID values. The key should be certified to prevent a man in the middle attack. The user imports public keys from others and places them on their public key ring. Note that there is no private key ring. I could have used the PGP method and made the private key a random number and then encrypted that number with a passphrase. This would be more secure but I was worried about users deleting their private key file. The 32-bit salt will discourage a pre-computed dictionary attack. An attacker would have to run over 4 billion SHA's and D-H's and store the result for every passphrase in their dictionary. To discourage a dictionary attack on a specific public key, I will include a tutorial on how to choose a secure passphrase. Encryption ---------- The program will generate a 160-bit random private session key "r" based on timed keystrokes by the user. A 1024-bit public session key "z" is calculated: z=g^r mod p z is stored in the file header. For each recipient, a "k" value is calculated using the recipient's public key: k=y^r mod p The session key r is now encrypted for each recipient by running each k through an SHA-1 hash and xoring the output with r: k'=SHA(k) xor r For each recipient the 160-bit k' value is stored with the recipient's 32-bit KeyID value in the file header. Each additional recipient adds 24 bytes to the file header. The plaintext is then encrypted with Blowfish in CBC mode using the 160-bit r value as the key. r is then discarded. Note that I use the same r key for the Blowfish session key and the Diffie-Hellman private key. I could have generated a separate r1 for Blowfish and an r2 for D-H but I don't think this is necessary. Decryption ---------- The public session key z is retrieved from the file header. Each recipient matches their KeyID with one of the KeyIDs stored in the file header. From this match they get their particular k' value. They enter their private key passphrase, append the KeyID salt and run it through an SHA-1 hash to get x. k is then calculated: k=z^x mod p The original private session key r is decrypted: r=SHA(k) xor k' The ciphertext is decrypted using Blowfish with key r. ======================================================= Does anyone see any obvious security problems that I might have overlooked? Kent Briggs kbriggs(a)execpc.com CIS: 72124,3234

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Warning about Pegasus Mail and PGP (fwd)
by anonymous-remailer＠shell.portal.com 17 Dec '03

17 Dec '03

Forwarded message. From: investor(a)flood.xnet.com (Investortools) Newsgroups: alt.security.pgp Subject: warning about PMail-PGP Date: 9 Dec 1995 00:47:46 GMT Organization: XNet - A Full Service Internet Provider - (708) 983-6064 Lines: 5 Message-ID: <4aambi$e33(a)flood.xnet.com> NNTP-Posting-Host: cyclone.xnet.com X-Newsreader: TIN [version 1.2 PL2] I just installed the "Open Encryptor" PGP interface for Pegasus Mail. I found that when you sign a message and queue it, it stores your password in the clear on the hard drive. Apparently it doesn't sign or encrypt the message until just before transmitting it. So it stores your PGP private key password with the message until it sends it.

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Re: .PWL spin
by Joseph M. Reagle Jr. 17 Dec '03

17 Dec '03

At 09:11 AM 12/9/95 -0800, Joel McNamara wrote: >Microsoft said it plans to strengthen the encryption, Bennett said. >Password data will be stored randomly, making it harder to find on the >computer, he added. Oh that is clever! (Security through obscurity!) Make it all the harder to back up the file! I had the minimal amount of security W95 allows one to have by having the default user not be able to do anything, then the me user to everything (for which you needed a password...) Of course my registry got corrupted (eudora beta for W95) and the only damn thing it did remember was that the default user couldn't do anything, and it no longer knew who I was... So now, I don't even bother with that, I'm just hoping securdrv, sfs, or something makes it to W95 one of these days... (I doubt either of those will make it...) _______________________ Regards, It is absurd to divide people into good and bad. People are either charming or tedious." -Oscar Wilde. Joseph Reagle http://farnsworth.mit.edu/~reagle/home.html reagle(a)mit.edu 0C 69 D4 E8 F2 70 24 33 B4 5E 5E EC 35 E6 FB 88

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Re: The Elevator Problem
by tcmay＠got.net 17 Dec '03

17 Dec '03

At 6:47 PM 12/8/95, Jerry Whiting wrote: >A group of us have been wrestling with a problem and I'd like to ask for some >outside help. We've come to call it the Elevator Problem. > >Alice and Bob want to establish a secret in from of Eve. In other words, >they want to agree on a secret key in an elevator full of Eve's. Isn't this just the "subliminal channels" scenario? Originally phrased in terms of prisoners under the watchful eyes of their jailers nevertheless establishing a private communication channel? Schneier describes this beginning on page 66 (of his 1st edition). Your scenario looks identical to this. So you should check out the papers on this in the Crypto Conference proceedings. As to whether you can implement this without using patented algorithms, I don't know. Not enough information given. --Tim May Views here are not the views of my Internet Service Provider or Government. ---------:---------:---------:---------:---------:---------:---------:---- 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: CP: Mailing List Subjects
by anonymous-remailer＠shell.portal.com 17 Dec '03

17 Dec '03

On Fri, 8 Dec 1995, Michael Handler wrote: > Learn procmail. It'll save you hours upon hours of time. > > :0: > * (^From owner-cypherpunks(a)toad\.com|^Sender: owner-cypherpunks(a)toad\.com) > lists/cypherpunks Would the following work?? :0 * (^From|^Sender).*owner-cypherpunks(a)toad.com |/usr/bin/contrib/procmail -m ~/.punk_rc Does anyone know where the procmail archives are?? That might help some of us out, especially those of use who are lousy at managing our very, very precious resources. Alice de 'nonymous ... <an455120(a)anon.penet.fi> ...just another one of those... P.S. This post is in the public domain. C. S. U. M. O. C. L. U. N. E.

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ideath remailer temporarily down
by Greg Broiles 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- The remailer located at remailer(a)ideath.goldenbear.com is currently unavailable because the local freenet (which handles DNS and MX service for goldenbear.com) is making some configuration changes. Apologies for not warning anyone, but I didn't get a warning either. Incoming mail for goldenbear.com should be spooling on sender's machines; I haven't received any since late Thursday (12/7) evening. I don't know when they'll get this fixed but I'm kinda pissed off about it and am exploring alternatives. Doh. I'm reachable as gbroiles(a)darkwing.uoregon.edu as well. -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQCVAwUBMMofY33YhjZY3fMNAQG7rwP/cLSbiqtDCm1frYSOqxTIitTaP/36v/7g W+azO+zC1+k6ozWaGwcCqtgwi2Kmbv/XtCnDbzzQdSI6k0rJFwhbw5rDkxQ4W5sQ 9PNHO9UC1F7JyAEs7kTiZSxZpkqRdzx98P06wRfy4Hwkzy7OuoYm2jHYNlHDojcv 9Jx6wYWVlIo= =QLxL -----END PGP SIGNATURE-----

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