December 2003 - cypherpunks-legacy

Re: I have FOIA'd the Clipper Key Escrow databases
by wcs＠anchor.ho.att.com 17 Dec '03

17 Dec '03

Eric Hughes writes: > Should John's FOIA request for the clipper key database work, it > creates a wonderful hole in the entire key custody system. > It would require a legislative act to plug the hole. Not necessarily - they may be able to claim there's a criminal investigation in progress (one of the standard FOIA loopholes) or they may lose the first round if there isn't one in progress so they'd have to go start investigating somebody (for corruption in government, or spies in the CIA, if nothing else is available :-) Since they don't know who the spy is, or who has which phone, everybody's key must obviously be relevant evidence... But it's clearly a fun opportunity. > Now, how many legislators do you know that are going to make a public > record by voting in favor of Big Brother? If the President supports it, why not a bunch of his fellow politicians? Bill

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Large Block DES Newsletter
by ritter＠cactus.org 17 Dec '03

17 Dec '03

Large Block DES Newsletter Vol. I, No. 1 Feb. 28, 1994 Terry Ritter, Ed. Current Standings for the Large-Block DES Proposals: I. NxM DES: A B v v k1 -> DES1 k2 -> DES2 v v C D Exchange Right 4 Bytes E F v v k3 -> DES3 k4 -> DES4 v v G H Falls to meet-in-the-middle like double-DES. Falls to a practical attack by Biham, now called "fix-in-the-middle." II. NxM DES Found Weak Announcement of above. III. Isolated Double-DES 2x construct found weak in original article. The 1x construct: A v k1 -> DES1 v B v km -> XOR v C v k2 -> DES2 v D was found weak by Chris Dodd <dodd(a)csl.sri.com> who pointed out that two different blocks of known-plaintext (A,D) and (A',D') will allow matching (B XOR B') and (C xor X'). (This is similar to Biham's "fix-in-the-middle.") Good going Chris! Also found by Stefan Lucks <lucks(a)namu01.gwdg.de>. IV. Ladder-DES A B | k1 | v v | XOR <- DES1-----| | | | k2 | | v v |---- DES2 -> XOR | | | k3 | v v | XOR <- DES3 ----| | | | k4 | | v v |---- DES4 -> XOR | | v v C D Joseph C. Konczal <jkonczal(a)nist.gov> points out that the construct is indeed vulnerable to meet-in-the-middle. I agree, but note that this seems to imply a 112-bit search. Since we don't need more than 112 or 120 bits of strength, I don't see it as a problem. (Indeed, if we could get more strength, we might want to trade it for speed anyway.) 112 bits (or so) is the design goal, which should be enough for a couple of decades. In a normal cipher design, I would expect each key bit to contribute toward strength, but these are hardly normal cipher designs. Especially when we try to expand block size, extra keys may simply provide another small block with the same strength as a previous small block. Keys will be delivered electronically, so the relatively rare delivery of 2x or 4x or even 8x the expected key material should not pose a serious problem. However, Biham reports: "ladder DES is not more secure than 2**88 steps and 2**64 chosen plaintexts." Now, 2^88 cipherings is 2^32 times as strong as the 2^56 currently in DES (and larger than Skipjack), but hardly the 2^112 intended. For the current design the current options are: 1) live with the 2^88 strength (so far!), 2) design the rest of the system to prevent chosen plaintexts, or 3) prevent more than, say, 2^32 block cipherings under a single key. Actually, we need to know exactly what the problem is, and the limits of it, before we can propose a fix, or decide whether the ladder-DES scheme is unfixable. Summary Three substantially different constructs proposed; of these, two fall, and one is wounded. To review, the intent is to find some relatively-simple construct which builds on the assumed strength of DES to deliver wide blocks and something like 112 bits of strength, with less processing than triple-DES. (I see no need for super-strength, unless it is free.) We still do not know whether or not this is possible.

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Fax / Modem question
by fnerd＠smds.com 17 Dec '03

17 Dec '03

(Please respond to this question by private email.) Is it possible to set up most fax/data modems to be ready to receive calls from either fax machines or data modems? If so, in this mode, does it make the beep that sets a calling fax machine going, or does the caller have to push a button to initiate the connection from his or her side? Ditto for data. Doesn't the answer side usually put out the first beep? -fnerd please reply to: fnerd(a)smds.com - - - - - - - - - - - - - - - blue mass, Pharm. a preparation of metallic mercury with other ingredients, used for making blue pills. -----BEGIN PGP SIGNATURE----- Version: 2.3a aKxB8nktcBAeQHabQP/d7yhWgpGZBIoIqII8cY9nG55HYHgvt3niQCVAgUBLMs3K ui6XaCZmKH68fOWYYySKAzPkXyfYKnOlzsIjp2tPEot1Q5A3/n54PBKrUDN9tHVz 3Ch466q9EKUuDulTU6OLsilzmRvQJn0EJhzd4pht6hSnC1R3seYNhUYhoJViCcCG sRjLQs4iVVM= =9wqs -----END PGP SIGNATURE-----

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Re: Dorothy Denning
by fischer＠charybdis.prl.ufl.edu 17 Dec '03

17 Dec '03

> I recall a profile of the Dr's Denning in one of the > popular cracker/phreax exposes, (maybe in Markov/Hafner?) > > Andy I believe you are referring to Bruce Sterling's "The Hacker Crackdown", interesting book because Sterling sympathetically presents many sides: paranoid telco's, testosterone-poisoned adolescent hackers, hand-wringing cops (Dr. Denning is presented in this milieu) and (my personal favorite) the "information wants to be free" libertarians. Randy Fischer

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clipper + enaction = illegal alternate encryption
by VACCINIA＠UNCVX1.OIT.UNC.EDU 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Jeremy(a)crl.com writes: >Now why bother going through all the trouble to take out the chip? Why >not just leave it in there and send RSA encrypted over your phone line? >Once they _DO_ decrypt your clipper, they will still have another barrier. >Leaving the chip in there does make it a little harder even for law >enforcement doesn't it? This is the reason all other forms of encryption will be outlawed if the clipper proposal goes through. I foresee at least two lines of enforcement. The first is that one is held in contempt of court (assuming they can find some charges to press) until you give them your key. How long can they keep you in the slammer on a contempt charge? This option is already available and seems to work, at least so far. The second is to make alternate encryption illegal and thus they will get you even if they have no evidence to charge you with. After all, if the police are monitering you AND you are encrypting information, you must be guilty, right? Encryption will be enough evidence to convict. This makes life easy for law enforcement and will surely be the next step after clipper. If they can't get you for the alleged crime you are committing then use of illegal encryption will provide a consolation prize. They really HAVE to make alternate forms of encryption illegal to make clipper of any value to them, despite the rhetoric we are now hearing (at least some people are hearing). Scott G. Morham !The First, VACCINIA(a)uncvx1.oit.unc.edu! Second PGP Public Keys by Request ! and Third Levels ! of Information Storage and Retrieval !DNA, ! Biological Neural Nets, ! Cyberspace -----BEGIN PGP SIGNATURE----- Version: 2.3a iQCVAgUBLXModj2paOMjHHAhAQH4IgQAy+sqJeI1JqDgtR4kayOuo5ovzcVpxfVM JTi7ZgwLppw859cKhQgGzHfWezpDYQxrYGEfOH4JqFXWUlqEyVgrDhIw2PVMO95p IkGDrU90O/RkUFg9lrEuWvxSXJvKX52Cz6jN7tj7DxkdXYutpc2z80QiPY1mtXN7 wr7XySZ9dzI= =BVk0 -----END PGP SIGNATURE-----

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Colorado Cypherpunks meeting
by nates＠netcom.com 17 Dec '03

17 Dec '03

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Insecurity of public key crypto #2 (reply to May)
by wet!naga 17 Dec '03

17 Dec '03

[The BBS I use seems to have brain damage. Apologies if this has already been posted.] >From: tcmay(a)netcom.netcom.com (Timothy C. May) >Subject: Re: Mac encryption >Date: Wed, 23 Feb 1994 09:56:40 -0800 (PST) > >Ron Davis writes: > >(quoting me [T.C.M.]) > >>>MacPGP, available by anonymous ftp from the soda.berkeley.edu site, is >>>the only one I know of using public key methods, and hence the only >>>one of real interest to Cypherpunks. > >The problem with symmetrical ciphers is one of *scaling*. > >Since a key must be exchanged with each other person, the total number >of keys growns rapidly as the community of participants increases. At >any stage, the key may be lost, stolen, observed, shared with the >Feds, etc. A community of 700 participants, as here on Cypherpunks, >would mean each person would have to generate, exchange (securely!), >and store 700 specific keys for use just with others. Anybody with 700 co-conspirators is asking for trouble, since at least one of them is sure to be a federal agent. Encryption is for concealing "sensitive" information. If it's not sensitive, why bother? If it is sensitive then you'd better be damn sure you can trust the person you're sending it to. >This is the famed "key distribution problem." > >With public key methods, this problem is largely solved. Each person >can generate his or her own key, publish the public key part of it, >and be done with it. It's not that simple. Terry Ritter has pointed out on sci.crypt that the problem with PGP is the validation of public keys used. In other words, the security hole in the use of PGP is not in the encryption methods used, or in the use of PGP itself, but in the possibility of being duped by someone (or some nefarious federal agency) spreading bogus public keys. It's not enough to have a public key which you believe is the public key of a person you wish to communicate securely with - you also have to be sure that the private key which corresponds to this public key is known only to that person, in other words, that the public key really did come from the person you believe it came from. If you get the (presumed) public key of some person X from some directory of public keys, or from some third party, how can you be sure it didn't originate with someone who wants to monitor all the encrypted messages being sent to X? Terry Ritter has explained how a third party can place themselves in the middle of encrypted communications between two people using PGP and monitor everything they say to each other - and this without having to crack RSA or IDEA. This method of eavesdropping applies only to public key encryption systems, not to secret key systems, so I suggest that the latter are still of interest (even to cypherpunks), not only for encrypting data that stays on your hard disk but also for encrypted communications. rom owner-cypherpunks Tue Mar 1 12:11:49 1994 Return-Path: <owner-cypherpunks> Received: by toad.com id AA28180; Tue, 1 Mar 94 12:11:49 PST Received: from wet.UUCP by toad.com id AA28156; Tue, 1 Mar 94 12:11:44 PST Received: by wet.uucp (/\=-/\ Smail3.1.18.1 #18.2) id <m0pbaUt-000CAaC(a)wet.uucp>; Tue, 1 Mar 94 11:52 PST Message-Id: <m0pbaUt-000CAaC(a)wet.uucp> Date: Tue, 1 Mar 94 11:52 PST From: wet!naga (Peter Davidson) To: cypherpunks(a)toad.com Subject: Insecurity of public key crypto #1 (reply to Mandl) Sender: owner-cypherpunks(a)toad.com Precedence: bulk [My BBS is having fits lately. Apologies if this has already been posted.] >Date: Wed, 23 Feb 94 12:13:57 EST >From: dmandl(a)lehman.com (David Mandl) >Subject: Re: Mac encryption > >The invention (discovery?) of public-key crypto changed the world, and >makes practical everyday use of crypto infinitely easier. Infinitely? You mean there is absolutely *no* difficulty involved in using PGP? I quit using it up quite a while back. Couldn't be bothered with the hassle. >It also makes >the kinds of specific things cypherpunks are interested in much more >practical (or POSSIBLE). Digital signatures, yes. I haven't had a need for 'em so far (I'm not setting up a digital bank). >If you correspond with hundreds of people on a >regular basis, including people you don't know and people you may send >something to once and never deal with again, it is impractical to say the >least to have to generate and exchange keys. Only "sensitive" information is worth encrypting and if you want to stay out of trouble you don't go giving sensitive information to someone you don't know. A certain mutual knowledge and trust between two people has to be establish before any exchange of sensitive information. >Why was public key crypto invented at all? Why are people interested in >using it? Practically, it's really fundamentally different from symmetric >crypto, which is of very limited use in the situation we're all in now >(anonymous communication, the net, quick hit-and-run dissemination of >information, digital signatures, etc., etc.). Crypto is for concealing information from those you don't want to see it. Public key crypto is thus not fundamentally different from symmetric key crypto. The difference is in communication of the encryption key, which is not a fundamental difference. Both kinds of crypto have problems when it comes to key distribution. In the case of secret key the problem is in keeping the key secret. In the case of public key the problem is in validating the public key. >PGP also has the "web of trust" structure built in. "Trust"? Sure. Just trust the person you got X's public key from (who got it from someone who got it from who knows?). So is X's public key really X's public key? Sure, just trust that it's so, then send X a message and trust that it won't be intercepted by whoever put out the bogus public key for X.

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Applied Crypto
by m＠BlueRose.com 17 Dec '03

17 Dec '03

Project Guttenberg has only books that are in the public domain e.g. very old books. I suspect that Bruce Schneier (and the publisher) would like people to buy Applied Cryptography. I found it to be worth the price. M Carling Begin forwarded message: Date: Tue, 1 Mar 94 18:45:49 EST From: fhalper(a)pilot.njin.net (Frederic Halper) To: cypherpunks(a)toad.com Subject: Applied Crypto Sender: owner-cypherpunks(a)toad.com Precedence: bulk Does anyone know if Project Guttenberg(or anyone else) has electronic books such as applied cryptography? Thanks, Reuben Halper

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Re: Colorado Cypherpunks meeting
by russw＠netcom.com 17 Dec '03

17 Dec '03

At 13:30 3/1/94 -0800, Nate Sammons wrote: >This saturday, the 5th of March, at 7:00pm in the Penny Lane >coffee shop, there will be a Colorado Cypherpunks meeting to >discuss the recent Clipper/Skipjack/FBI DTB problems. > >Please tell anyone in the area (Colorado) who is interested to >please show up. It's on the South-west corner of 18th street >and Perl. > Nate, I know people in Colorado who would be interested in going... if you told them what city it might be in. Denver? Russell Russell Earl Whitaker russw(a)netcom.com Director, Extropy Institute 408-366-5435 ================================================================

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the nsa
by nobody＠soda.berkeley.edu 17 Dec '03

17 Dec '03

we of the cypherpunks mailing list certainly admire the nsa, perhaps more than any other agency anywhere in the world. because of this admiration, i would like to have a large, color jpeg of the director of the nsa. i will uuencode this and mail it to many many people. could someone post such a jpeg to cypherpunks, or perhaps point me to where i might find one, or point me to a book or magazine that would have one, so i can scan it in? it's ok if the image is a bit noisy. thanks, nobody

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