- cypherpunks-legacy - lists.cpunks.org

Re: numbers don't lie
by JMKELSEY＠delphi.com 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- [ To: cypherpunks ## Date: 03/04/96 07:59 pm ## Subject: Re: Numbers don't lie... ] >Date: Sun, 18 Feb 1996 11:18:57 -0500 (EST) >From: "A. Padgett Peterson P.E. Information Security" >Subject: Numbers don't lie... >In their figures, they do seem to gloss over a couple of minor points: >The most compelling to me is "how do you know when you broke it ?". >Bruce has always used the "known plaintext" approach, however using >modern techniques for messaging, *every* message has a different >session key, negotiated using assymetric keying so the only message >that will be broken is one that you already have - not terribly >helpful. Coming up with a short length of known plaintext isn't usually a big problem. For example, attacking DES, you need to know one 64-bit block. In many cases, this is easy to do. While it is possible (and a good idea) to build communications software so that it's relatively hard to get known plaintext, this shouldn't be necessary to use a cipher securely. And in any case, if you're encrypting ASCII text, the bit distributions give you a big clue about whether this is a reasonable key guess or not, after just a few decrypted plaintexts. This increases the cost of the search machines, but I'm not convinced that this will be an enormous increase in all cases. >This means that the strength of cryptography should be appropriate >to the value of the information protected. If less than U$10,000, >the message is individually encrypted, and has value only today, >then DES is probably "good enough". True, DES is probably good enough for the very lowest-value messages. But why use something that's barely acceptable, when it costs you almost nothing at all to make it really secure against keysearch attacks. Blowfish, SAFER-SK128, GOST, and 3DES are all apparently quite hard to break, and they are all far more resistant to keysearch attacks than DES. >Strategic information of higher value arguably needs "more" but how >much ? 64 bits is 256 times stronger than DES. This would indicate >effective security up to say U$2.5 million. More is better but I >would not be quite so alarmist nor would I dismiss the cost of >engineering. Non-trivial. The problem here is that it's not really reasonable to expect the users of a secure e-mail package to know what the state of the art is in terms of keysearch machines, and it's not always reasonable to expect the person that's sending some piece of information to know whether this is "you-bet-your-company" material. There's no excuse for leaving yourself vulnerable to keysearch attacks, when there are so many good, unpatented ciphers with key lengths of more than 100 bits. It's like building a car with an engine that you know will catch fire if it's ever run at more than 80 MPH, but justifying it by saying "well, most trips don't require more than 80 MPH to get where they're going anyway. In those special cases where greater speed is necessary, they'll just have to take a bullet train." >Still, at what point is it simply easier/cheaper to buy someone who >knows the secret ? Limiting your key to 56 bits means that an attacker has more options--if he can't bribe, blackmail, or threaten his way into your private communications, he can spend some money, and still get in. (Escrowing your key adds to the list, because he now has more people to bribe/threaten/blackmail, and he may also be able to carry out protocol attacks against the key escrow mechanism.) > Warmly, > Padgett --John Kelsey, jmkelsey(a)delphi.com / kelsey(a)counterpane.com PGP 2.6 fingerprint = 4FE2 F421 100F BB0A 03D1 FE06 A435 7E36 -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQCVAwUBMTujGkHx57Ag8goBAQElEwP/ZpzwCpwGUhbHJvEl+EiuseNEgy9To5yl RyX3VkdX+Xx6jksZeuLlSuRoMlahxyMHdH7uDY/8GFW2uxh8dFAJfwNdBCf3k0W8 aYml2Z/CCVadeuiSrKgZEMvE3F/LlDSCXQwuIde1Su7ICxQz9pd8ZbAqvOdQQWyZ ZQPr9TPCo/s= =zM5N -----END PGP SIGNATURE-----

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Re: PGP to PC mail integration
by E. ALLEN SMITH 17 Dec '03

17 Dec '03

From: IN%"willer(a)carolian.com" 1-MAR-1996 18:50:23.84 >I wrote: >> You'd put something into the mail message itself that would tell it >>"don't encrypt this" and/or "don't sign this". Hmm... you'd need to put in >>messages to be signed and/or encrypted your passphrase, or have it gotten >>some other way... which doesn't look very safe. >Not very user-friendly either. That depends on one's standards. I prefer text-based interfaces, and they are needed for many setups. >Usually the proxy would be on the same machine as the mail program (i.e. "your >machine"). That would mean the "attack proxy" would have to be installed on >the user's PC, and if someone has that kind of access to your machine, their >secret keyring is vulnerable anyway. Good point. This also argues against the passphrase into the mail being that much of a problem... with the massive exception of something going wrong with the mail proxy program so that it lets through the email, with the passphrase and possibly without any encryption. However, as has been pointed out on other aspects of this, one could have the passphrase entered once (in a special mail message with no valid To: address, for instance) per session. -Allen

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Re: hammers, crowbars and remailers & Leahy
by Mutant Rob 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Jean-Francois Avon (JFA Technologies, QC, Canada) wrote: > What is the difference between an small hardware store owner > selling a hammer and a crowbar to a guy that will commit burglary and > a remailer owner providing services to , say, the same burglar > who wants to sell his stolen goods.[..] Be wary. There are people who believe gun or ammo manufacturers (and even knife manufacturers) should be held responsible for criminal use of their products. Bartenders or party hosts are already responsible when one of their patrons or guests gets too drunk (though the connection with knowing that the person is wasted is a bit clearer there.) The people who support such liabilities think there is a clear connection and it isn't very good. You may as well argue about religion or how many angels can fit on the head of a pin with such people. They go by emotional arguments, in many cases because they've a personal connection as or with a victim of some crime. - --- [This message has been signed by an auto-signing service. A valid signature means only that it has been received at the address corresponding to the signature and forwarded.] -----BEGIN PGP SIGNATURE----- Version: 2.6.2 Comment: Gratis auto-signing service iQBFAwUBMUDuyCoZzwIn1bdtAQEqoQGAuU6nvataj6gt4VNUVjgyuYaTe8QxQ4Ww tPxTQiEvS/4C3C3vVUQ4QNWQbt5DxXzu =JRj/ -----END PGP SIGNATURE-----

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Welcome to Switchboard
by registrar＠switchboard.com 17 Dec '03

17 Dec '03

Thank you for registering in the Switchboard database. Your Switchboard login is: Email: cypherpunks(a)toad.com Password: JimArts This password is case sensitive. Once you log in (set your browser to http://www.switchboard.com) your entry appears in the directory with your email address attached. You may then update your listing to show exactly the information you want and correct errors. Note that Switchboard waits until you log in to change the directory, because this step verifies that your email address is correct. Logging in also allows you to create an additional listing, change your password, list your home page URL, unlist your main listing, and access other features. Once you are logged in, please change your password to make it easier to remember. If you did not register in Switchboard and received this message erroneously, please Reply to Registrar(a)switchboard.com.

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Re: Remailer passphrases
by frantz＠netcom.com 17 Dec '03

17 Dec '03

At 5:43 AM 3/12/96 -0500, Gary Howland wrote: >On Mon, 11 Mar 1996, Gary Howland wrote: >> root access to the system, something like "strings /dev/kmem" could narrow >> the search for the passphrase down significantly. Of course one could >> obfuscate the passphrase by XOR'ing it with 0x80, but that's only security >> through obscrurity. > >Sure, _if_ they were able to gain root access without rebooting the machine, >but the usual scenario is that the filth turn up with black bin liners, not >men from the NSA. The bottom line of all cryptography is that there is something that must be kept secret. Since it must be kept secret, there is always a significant level of paranoia about the means to keep the secret. For example, one could imagine an attacker attaching a logic analyzer to the CPU chip, unloading the on-chip caches and then rummaging thru the system memory for the secret. One of the reasons classical (government) crypto users change keys frequently is to minimize the amount of data compromised by a broken key. We keep hearing about NSA decrypting 20 year old cyphertext and showing more of the workings of the atomic spy rings operating in the 40s and 50s. If an opponent can rubber hose the key, her job is easy. If she has to perform cryptoanalysis, it is much harder. Remailers should regularly change their keys to avoid compromising previously recorded traffic. (They can have a long lived key for signing their traffic keys.) Regards - Bill ------------------------------------------------------------------------ Bill Frantz | The CDA means | Periwinkle -- Computer Consulting (408)356-8506 | lost jobs and | 16345 Englewood Ave. frantz(a)netcom.com | dead teenagers | Los Gatos, CA 95032, USA

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Re: A lengthy preliminary analysis of the Leahy bill.
by jamesd＠echeque.com 17 Dec '03

17 Dec '03

At 12:26 PM 3/11/96 -0500, Peter D. Junger wrote: > (4) the authority and ability of investigative and law enforcement > officers to access and decipher, in a timely manner and as provided > by law, wire and electronic communications necessary to provide for > public safety and national security should also be preserved; This provision of the bill makes the entire bill a worthless pile of repressive shit, despite all the pious good intentions in the rest of the bill. A little constitutional history: The supreme court used to rule that congress could not delegate its own power to bureaucrats, as this violated the principle of rule of law. Thus congress could pass a law than in a certain situation you had to do such and such, or refrain from doing so and so, but it could not pass a law that in a certain situation you had to do whatever some bureaucrat told you to do, because that would violate separation of powers and the principle of the rule of law, not men. Roosevelt threatened to stack the court, the court submitted, and the rule of law in the US was radically diminished. The proposed bill would seem to give bureaucrats the power to set aside the first, fourth, and fifth amendments, at whim. --------------------------------------------------------------------- | We have the right to defend ourselves | http://www.jim.com/jamesd/ and our property, because of the kind | of animals that we are. True law | James A. Donald derives from this right, not from the | arbitrary power of the state. | jamesd(a)echeque.com

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Re: Bell, Detweiler, Ravings, and Whatnot
by nobody＠REPLAY.COM 17 Dec '03

17 Dec '03

Timothy C. May writes in answer to jim bell - |Screaming insults at people, resorting to ad hominem attacks on their |personality (such as Jim did with Padgett Peterson), ranting about how |people are fools and worse, and generally foaming at the mouth...these are |behaviors which cause people to be dismissed as jerks, paranoids, and |killfile occuppants. |I have nothing against you, Jim Bell, but you are coming across as a loon, |as someone who clearly needs some kind of anti-psychotic medication. This is not supposed to be an insult?? |You rant, you quote excessively, you dissect short comments with |pages-long diatribes Says the one complaining of jim making ad hominem attacks.

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Re: Do you feel lucky, punk?
by jim bell 17 Dec '03

17 Dec '03

At 05:54 PM 3/11/96 -0500, Black Unicorn wrote: > > >[rant including some very dubious abstracts of legal opinions deleted] > >Not only is your law poor and badly reasoned, Just what George Will said about this recent Bennis SC decision. > your mastery of the jurisprudence of forfeiture law flawed, Ditto, and I notice you give no specific examples. Why is that? > and your rhetoric twisted, Again, you give no specific examples. And what is "twisted rhetoric", at least as you've used it here? >but you don't seem to know the difference between dicta and holdings. I didn't use either term. Neither did George Will. Maybe you read that item too rapidly to notice that most of it was George Will's column, not my wording. BTW, I get particularly suspicious when people "respond" to my posts and quote NOTHING that I have said. This seems to be a pattern: The person clearly disagrees with my position in general, but can't cite specifics and in fact studiously avoids them. Padgett Peterson is an expert at this, it appears you're trying to emulate him. What, then, was the point of sending me the note, as well as wasting bandwidth on CP to share your unhappiness? Jim Bell jimbell(a)pacifier.com

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Key Escrow: Scholarly Treatment
by Black Unicorn 17 Dec '03

17 Dec '03

Interested cypherpunks might want to have a look at: "A puzzle even the codebreakers have trouble solving: A clash of interests over the electronic encryption standard," in the most recent issue of Law and Policy in International Business, The International Law Journal of Georgetown University Law Center. Mr. Sean M. Flynn does a fairly good job of outlining the policy issues, even if perhaps he managed to go a bit light on the NSA and miss some of his history re: the marketing of broken systems to the private sector and third world nations, and the mistrust the NSA seems to have earned as a result. I was also disturbed to see him fall into the government's "voluntary standard" trap but still, it's really nice to see a legal note with cites like: See e.g., Bruce Schneider, Applied Cryptography (1994) John Perry Barlow National Security Agency, Recruiting Brochure Unclassified Summary: Involvement of the NSA in the Development of [DES] Marc Rotenberg Whitfield Diffie Jim Bidzos mech(a)eff.org (I kid you not) Wired and A personal interview with D. Denning Worth the read, nice bit of research, if lacking in the "spirit" of things. --- My prefered and soon to be permanent e-mail address: unicorn(a)schloss.li "In fact, had Bancroft not existed, potestas scientiae in usu est Franklin might have had to invent him." in nihilum nil posse reverti 00B9289C28DC0E55 E16D5378B81E1C96 - Finger for Current Key Information

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[noise] Re: Do you feel lucky, punk?
by Gary Howland 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Black Unicorn write: > On Mon, 11 Mar 1996, jim bell wrote: > > Remember, one of the basic assumptions that any supporter of the Leahy bill > > could be making is that it will be interpreted INTELLIGENTLY by courts. > Wrong. The assumption is that the rules of statuatory construction and a > long history of weighing legislative history will be used in intrepreting > the statute. Surely one of the basic assumptions of the supporter of any bill is that it _will_ be interpreted intelligently? [Note - Jim is not saying this is the _only_ assumption]. It's hard to make bills foolproof, since fools are so ingenious ... Gary - -- pub 1024/C001D00D 1996/01/22 Gary Howland <gary(a)kampai.euronet.nl> Key fingerprint = 0C FB 60 61 4D 3B 24 7D 1C 89 1D BE 1F EE 09 06 - --- [This message has been signed by an auto-signing service. A valid signature means only that it has been received at the address corresponding to the signature and forwarded.] -----BEGIN PGP SIGNATURE----- Version: 2.6.2 Comment: Gratis auto-signing service iQBFAwUBMUVZ8ioZzwIn1bdtAQGj7QGAjQfpDDRD0LSqjEe0NqECd7mTe4coqPm6 mvRoQzFqmZxggtMjldvVj3R8T4cfir2A =YtOX -----END PGP SIGNATURE-----

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