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RE: RE: Binding cryptography - a fraud-detectible alternative to
by everheul＠mail.rijnhaave.nl 17 Dec '03

17 Dec '03

To explain the backround of "binding cryptography" once more; with respect to (interoperable, worldwide) security in the information society socities/governments have to achieve two tasks: 1. stimulating the establishment of a security structure that protects their citizens, but which does not aid criminals. 2. Coping with the use of encryption by criminals outside of this framework. An inherent problem with these tasks is that different socities/governments have different views on the matter. So to achieve the first task you'll need a concept behind the security structure that is flexible enough to incorporate *any* crypto policy, i.e. from liberal (Japan) to non-liberal (France). We believe that "binding cryptography" is flexible enough to achieve this: a liberal crypto policy might use no Trusted Retrieval Parties at all, while a very non-liberal country might want one (government controlled) TRP, a compliance check on all network traffic and a ban on other crypto. With binding cryptography the issue on a crypto policy becomes non-technical and politically debatable: which features does a country want and what implementation? Adam Back[SMTP:aba@dcs.ex.ac.uk] wrote: > This much is the same as clipper I, just the parties have been > renamed (TRP = split escrow key database holders, TTP = US > government). No it is not. Among other things: it is a international solution, it is based on Pub. Key. Enc. and it is flexible enough to follow private-sector developments. It is not a key-escrow solution, as *you* have (in principle) a very large choice in who to trust with your communication. Hal Finney[SMTP:hal@rain.org] wrote: >Another flaw with schemes of this time (in terms of failing to meet >their goals) is that they cannot detect superencryption and other >forms of non-standard encryption of the message body proper. All >they can really do is verify from the outside that the same session >key is encrypted for the two recipients (the intended recipient and >the Government Access to Keys Party - let's not abuse the term by >calling him a Trusted Third Party). But they can't be sure that the >session key is sufficient information to decrypt the message. We offered a solution for the *first* task not for the *second*; the point is that criminals(!) do not gain any real advantage from using the system in that way as they - among other things - still face the key-management problem. The above dicussions are only relevant in countries where the use of crypto outside the structure would be prohibited. BTW, it is by such discussions that I believe such a ban is ineffective and in fact counterproductive. Adam Back[SMTP:aba@dcs.ex.ac.uk] wrote: > The paper suggests that in one plausible implementation, the > checkers referred to could be network service providers: > > from the summary of the paper posted here: >: The idea is that any third party, e.g., a network or service >provider, > ^^^^^^^^^^^^^^^^^^^^^^^^^^^ >: who has access to components 2, 3 and 4 (but not to any additional >: secret information) can: : a. check whether the session keys in >components 2 and 3 coincide; : b. not determine any information on >the actual session key. > > This would allow for instance for a software only implementation of > a madatory key escrow system. The government in question could then > deputize ISPs to do their mandatory GAK compliance checking for > them. (Deputizing companies is a recent trend in law enforcment > techniques anyway). > > This would allow for instance IP level encryption, with > non-conforming encrypted packets being dropped by all ISPs in the > country in question. Something the Singaporeans might find useful. > The checking functionality could also be added to a key escrow > enabled router. > > For this kind of application, binding cryptography is spot on. Jim bell[SMTP:jimbell@pacifier.com] wrote: > I think the biggest problem with allowing "anyone" to check the > correctness of a key is that what is a technical possibility today, > will become a legally-mandated requirement tomorrow. What if > Internet backbone companies and/or ISP's were told that they had to > implement software check these keys, and if they discovered an > "incorrect" escrowed key, they were legally obligated to either > refuse to forward that message, and/or forward a copy of that > message to someone like Spooks(a)NSA.gov or Thugs(a)DOJ.gov. The information society is international by nature; we want to securely communicate with Singapore. If Singapore, a democratic country!, has such a crypto policy that they want the above control, then so be it. Don't blame "binding cryptography" for making that possible, but start a dialogue with your politicians on what features of the proposal are acceptable in your country. Some countries seem to have the philosophy that "law-abiding" citizens should have nothing to "hide" from their government, so should not use encryption at all. I think that that is not acceptable. The concept behind the third-party checking is that no "law-abiding" citizen should have any problem that abuse - and only that - of a *voluntary* system can be "seen" by many parties. If and *how* checking is done, is a matter of each society. The same concept holds for many things in life and is well accepted. For instance that is why cars have registration plates: if a car drives through after an accident on a *public* road, then by-standers (third parties) can observe that. I for one don't the information society to be the wild west, where anything goes. Of course, people are rightfully worried that such a checkable system might be abused by a totalitarian regime to control their citizens. However, as long as such a system is voluntary I see no problem. Signs in the USA indicate (cf. the NRC study & remarks of the president) that use of other systems will always be possible. Also, the above discussions already showed that if such a system is voluntary, then there are lots of way to go around it. Adam Back[SMTP:aba@dcs.ex.ac.uk] wrote: > As your paper describes, your system allows anyone to check the > correctness of the escrowed session key. Have you considered > modifying it so that the only person who can check is the owner of a > designated private key of a public/private key pair? This would > allow say for the TTP to check correctness, and not the TRP, nor the > public. I'm not sure of the usefulness of this, but it allows you to > select from the full spectrum according to requirements: > > a) no one can check, PGP second recipient (Carl Ellison, Bill > Stewart) b) recipient only can check (my suggestion) c) holder(s) of > designated keys can check d) anyone can check (your proposal) > > c) should be easy to acheive: restrict d) by having the sender > encrypt the escrowed session key a second time to this public key. Point a) can be circumvented too easily. How do you envision point b? Sending all keys (or a selection) to the recipient for checking is: impractical & dangerous (you want the distance between the actual communication and the guy that can decypher as large as possible). If you don't send keys, then abuse will only show up during a warrant. But that abuse will show up anyway.. So what is the use? Point c is a nice suggestion. Although I for one have no problem that anyone can see that I comply with the rules (..unless of course it is a non-voluntary system etc..). Adam Back[SMTP:aba@dcs.ex.ac.uk] wrote: > My assumption was that a TRP is a government front. (All of the > proposed clipper I escrow agents have been major US defense > contractors/government agencies, in addition the clipper I documents Bring in to action your politicians ("the voice of the people") to let the regulation on Trusted Retrieval Parties be as liberal as you find acceptable. Peter M Allan[SMTP:peter.allan@aeat.co.uk] wrote: > 1) What's in it for the user ? > 2) What happens when the Feds recover meaningless data? 1) They get *one* system set up by governments that will make it possible to securely communicate (and do with business) with the whole (democratic) world. Instead of several partial systems set up by private companies where responsibilities will be vague. I consider a certified public key as a digital passport; setting up the structure for passports is a task of governments. 2) Only during a warrant policemen will see that; what then happens must every society on his own decide. Probably nothing happens, as otherwise the investigation will probably be to disturbed. Best regards, Eric

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Re: SPA sues C2, other ISPs and users
by Duncan Frissell 17 Dec '03

17 Dec '03

At 03:34 AM 10/13/96 -0700, Greg Broiles wrote: >In the Ninth Circuit, the standard for contributory infringement is "[o]ne >who, with knowledge of the infringing activity, induces, causes, or >materially contributes to the infringing conduct of another, may be held >liable as a 'contributory' infringer". _Fonovisa v. Cherry Auction_ 96 >C.D.O.S. 517 (CA9, 1996) But how will a civil action be effective as soon as millions of people have 10 mb/s full-time net connections and can be their own ISPs and judgment proof at the same time? DCF

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Re: exporting signatures only/CAPI (was Re: Why not PGP?)
by azur＠netcom.com 17 Dec '03

17 Dec '03

>Steve Shear <azur(a)netcom.com> writes: >> >The problem however, is finding a non-US site to hold the hot potato >> >once it has been exported. For example 128 bit Netscape beta was >> >exported a while ago. I don't see it on any non-US sites. This is >> >due to Netscape's licensing requirements, you need a license to be a >> >netscape distribution site, the license doesn't include the right to >> >mirror non-exportable versions on non-US sites. >> >> That's one good application for remailers, and .warez newsgroups. at. > >I don't know of any advertised files by email services using nym >servers, where the file request, and the files are both sent via >remailers. > >The problem with this is currently is that the nym servers couldn't >stand up to the scrutiny if SPA or whoever got interested. The >message flood attack on the nym would reveal the services host. > >The BlackNet architecture solves this problem by posting requests >encrypted with the services key to a newsgroup, but USENET newsgroup >disitribution time is slow (*), and people are spoilt these days with >WWW, and expect results now, not days later. Has anyone tried this to see whether the LOS would or wouldn't be acceptable? > >The requested file can be posted via mixmaster. You would want to use >a different, random chain of remailers each time. A reverse message >flood could reveal the host also, as you can request lots of copies, >and the service will blindly serve the files. (If someone wants to >discover the service host, they send 1000s of requests, then sit back >and watch which user sends most data into the remailer net.) On a related note: I've been charged with developing an Internet service which needs to assure its clients of anonymity. However, we fear some clients may abuse the service and we wish to prevent the abusers from re-enrollment if terminated for misbehavior. (In your example, it would be the person(s) trying to discover the service host via flood). My thought was to base enrollment on some sort of 'blinding' of their certified signature (e.g., from Verisign) which produces a unique result for each signature but prevents the service from reconstructing the signature itself (and thereby reveal the client's identity). I'm calling this negative authentication. Have you come across anyone who has considered this problem or another one which is mathematically very similar? > >To combat this the service could impose a limit on the number of >copies it would serve per day. This allows a denial of service >attack, if someone wants to stop anyone else getting a copy, they just >saturate the service. Still an improvement over no limit. If the service could negatively authenticate users it would need such limits and might not be subject to such attack. > >Of course Ross Anderson's `eternity service' provides the general case >solution for distribution of such data. It is complex to implement >well though. I've never heard of the eternity service. Where can I get more information? BTW, would Eric Hughes' Universal Piracy System also solve such a situation, by distributing or parking snippets of encrypted file data across many 'cooperating' ftp (or whatever access/storage mechanism) sites. Perhaps the negative authentication approach would help here too by preventing flood/denial of service attacks against the 'key' sites. If only snippets of encrypted data are stored on any one host it might make the SPA's goal even more elusive legally. PGP Fingerprint: FE 90 1A 95 9D EA 8D 61 81 2E CC A9 A4 4A FB A9 --------------------------------------------------------------------- Snoop Daty Data | Internet: azur(a)netcom.com Grinder | Sacred Cow Meat Co. | --------------------------------------------------------------------- Counter-cultural technology development our specialty. Vote Libertarian. Just say NO to prescription DRUGS. "Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive." -- C.S. Lewis "Surveillence is ultimately just another form of media, and thus, potential entertainment." -- G. Beato

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Re: SPA sues C2, other ISPs and users
by azur＠netcom.com 17 Dec '03

17 Dec '03

>>A few months ago I saw Sameer grumbling about people "not paying for >>Apache-SSL". Now SPA claims he's operating an ISP to promote piracy. So >>first he's a software publisher and now he's a software pirate. Uh, yeah, >>whatever. Obviously SPA is on a PR campaign here which defies all >>conventional logic. > >It looks to me like they're trying to achieve results through fear and >intimidation that they can't reach via persuasion; e.g., they are trying to >create a climate where ISP's turn over user information without a fuss >because they don't want to be sued themselves; and where users (and home >page "publishers" or authors) are afraid to even discuss infringement, or >do anything even close to the conceptual lines between fair use, >noncommercial alterations of works (a la _Galoob v. Nintendo_ 964 F.2d 965 >(CA9, 1992), where defendants' marketed a "Game Genie" which altered the >play of Nintendo cartridges used in concert with it, held to be >noninfringing), and infringement. In Sameer's case they may not get far with forcing him to reveal user identites since any one of them with intelligence is probably using ecash or money orders for payment (something he encourages to protect anonymity). Where's Eric Hughes' Universal Piracy System now that we need it? PGP Fingerprint: FE 90 1A 95 9D EA 8D 61 81 2E CC A9 A4 4A FB A9 --------------------------------------------------------------------- Snoop Daty Data | Internet: azur(a)netcom.com Grinder | Sacred Cow Meat Co. | --------------------------------------------------------------------- Counter-cultural technology development our specialty. Vote Libertarian. Just say NO to prescription DRUGS. "Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive." -- C.S. Lewis "Surveillence is ultimately just another form of media, and thus, potential entertainment." -- G. Beato

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[Book] The Cobweb
by Adam Shostack 17 Dec '03

17 Dec '03

Just finished with 'The Cobweb' by Neal Stephenson and his uncle,* writing under the nym Stephen Bury. The Cobweb is entertaining, and easily worth the $14 I paid. Its cpunk relevance is a little limited except for the Iowa deputy sheriff who figures out an Iraqi biolological weapons scheme in the US, while the CIA, FBI and NSA fight State, Agriculture and each other over how, or if, to react. Mercenary Soviet Antonov transport planes, stateless Kurds, and encrypted radio links all play their parts. We never do find out if the NSA can decrypt them in time. ISBN 0-552-37828-7. Bantam, Sept 1996. *I forget his uncle's name; hes a history professor who can't be seen writing books with a Sci-fi author like Neal. The usefulness of nyms. They also wrote 'Interface.' -- "Every year the Republicans campaign like Libertarians, and then go to Wasthington and spend like Democrats." Vote Harry Browne for President. http://www.harrybrowne96.org

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Re: L.Detwieler
by Tom Lojewski 17 Dec '03

17 Dec '03

How do I get off this list? >To: cypherpunks(a)toad.com >Subject: Re: L.Detwieler >From: dlv(a)bwalk.dm.com (Dr.Dimitri Vulis KOTM) >Comments: Dole/Kemp '96! >Date: Wed, 09 Oct 96 18:11:29 EDT >Organization: Brighton Beach Boardwalk BBS, Forest Hills, N.Y. >Sender: owner-cypherpunks(a)toad.com > >"Butler, Scott" <SButler(a)chemson.com> writes: > >> Clipped from WELCOME TO CYPHERPUNKS >> >The cypherpunks list has its very own net.loon, a fellow named L. >> >Detweiler. The history is too long for here >> >> Can anyone give me the details of The History of this character and wot >> he is on about > >Is it time to update the welcome text and add yours truly to it? > >Timmy May is an asshole. > >--- > >Dr.Dimitri Vulis KOTM >Brighton Beach Boardwalk BBS, Forest Hills, N.Y.: +1-718-261-2013, 14.4Kbps > > --------------------------------------------------------- Tom Lojewski - ProNet Consulting - lojewski(a)earthlink.net

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Re: pgp, edi, s/mime
by Hal Finney 17 Dec '03

17 Dec '03

Thanks for the kind words about my participation with PGP Inc. My comment was really meant more as a disclaimer, though. Realize that I am now a corporate employee in the field rather than a hobbyist, so set your mental filters accordingly. Also, my activities right now are mostly a matter of helping with the finishing touches. Hard work over the past couple of years by Colin Plumb and Derek Atkins has produced the bulk of the code base for PGP 3 and the follow-on products. Still it is very exciting and gratifying for me to be working in this field which I love and which is so important, and I am enjoying it very much. Hal

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Op-Ed piece
by azur＠netcom.com 17 Dec '03

17 Dec '03

We all complain how the media are actively ignoring the crypto issues during the campaign. Here's a chance for us to quickly do something with some impact beyond our group. I'm looking insert an (1000-2000 word) op-ed piece or letter to the editor in my local Sunday paper presenting a non-technical, Libertarian/cypherpunk, view of the present crypto situation, our objections to the government's proposals, etc. Does anyone have a suggestion on where to find such an animal? I'd rather not spend the next day or two writing one. Perhaps we could coordinate a plan to have the same piece inserted next Sunday in various newspapers. -- Steve

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binding cryptography
by um＠c2.net 17 Dec '03

17 Dec '03

liberal (Japan) to non-liberal (France). We believe that "binding cryptography" is flexible enough to achieve this: a liberal crypto policy might use no Trusted Retrieval Parties at all, while a very non-liberal country might want one (government controlled) TRP, a compliance check on all network traffic and a ban on other crypto. I doubt that even French internet providers would want their routers to perform six modolo exponetiations and four modolo divisions whenever someone opens a secure socket... We offered a solution for the *first* task not for the *second*; the point is that criminals(!) do not gain any real advantage from using the system in that way as they - among other things - still face the key-management problem. The above dicussions are only relevant in countries where the use of crypto outside the structure would be prohibited. Of course, criminals do get real advantage from this system. They can use strong encryption for their messages and super-encrypt them using "binding" cryptography. So their illegal messages look perfectly inconnous as long as their government trusts in the "binding" property of this scheme. Only when the GAK key holder tries to decrypt a message, they notice that they cannot read it. Can you imagine that anyone would ever create a program that tries to look like a conforming implementation, but generates invalid "binding" data -- when it is so much easier to simply use PGP, and (if necessary) disguise that fact using the government-approved encryption software? I don't, so in my opinion the verification process is abolutely useless. One might say, binding cryptography, like several other cryptographic protocols, is a nice 'solution', but one with no corresponding 'problem' in the real world. :) It doesn't help in legitimate law enforcement, but it causes trouble to network operators and it deprives law-abiding citizens of their privacy. And criminals don't face "the key-management problem". In any GAK scheme, the official keys can be used to certify other un-escrowed encryption keys. Binding cryptography makes it just a little easier, because there is no need to create any "illegal" key pairs. Everyone can encrypt messages using the government-certified ElGamal keys, and then repeat that process, this time including the data required for goverment access. that use of other systems will always be possible. Also, the above discussions already showed that if such a system is voluntary, then there are lots of way to go around it. Criminals will always find ways around these systems -- even if they are mandatory. Just those who actually "have nothing to fear", will not go in the risk to use illegal encryption. So governments can wiretap law-abiding citizens, but not criminals. What useful is a system like that? -- one ring to rule them all, one ring to find them one ring to bring them all and in the darkness bind them in the land of mordor where the shadows lie.

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RE: RE: Binding cryptography - a fraud-detectible alternative to
by jim bell 17 Dec '03

17 Dec '03

At 11:48 AM 10/13/96 +0000, everheul(a)mail.rijnhaave.nl wrote: >To explain the backround of "binding cryptography" once more; with >respect to (interoperable, worldwide) security in the information >society socities/governments have to achieve two tasks: 1. >stimulating the establishment of a security structure that protects >their citizens, but which does not aid criminals. I think this is a phony distinction. Practically every product sold today could arguably "aid criminals." It isn't possible to prevent this. And that's the problem with your thinking above: If government argued that it had the authority to regulate any product that, arguably, "aided criminals," then it would automatically be able to regulate anything. > 2. Coping with the >use of encryption by criminals outside of this framework. > >An inherent problem with these tasks is that different >socities/governments have different views on the matter. Given that item we just read about Burma illegalizing the non-authorized use of fax machines and modems, that is a vast understatement! > So to achieve >the first task you'll need a concept behind the security structure >that is flexible enough to incorporate *any* crypto policy, i.e. from >liberal (Japan) to non-liberal (France). Just a second! WHy should technology bow to government policy? Until now, the microcomputer industry has pretty much developed and sold products without much or any (?) regard for what governmental policy would desire. In fact, it isn't even clear that governments have had much opinion about the direction that the microcomputer markets should go. Why should we start adjusting business policies and product capabilities in a way which is hostile to customers, just because the government wants this? > We believe that "binding >cryptography" is flexible enough to achieve this: a liberal crypto >policy might use no Trusted Retrieval Parties at all, while a very >non-liberal country might want one (government controlled) TRP, a >compliance check on all network traffic and a ban on other crypto. Why not ___NOT___ help these guys out? Do they somehow deserve to be assisted in the subjugation of their people? Does the name "Zyklon B" ring a bell? >With binding cryptography the issue on a crypto policy becomes >non-technical and politically debatable: which features does a country >want and what implementation? I would much prefer a situation where freedom is provided and/or guaranteed by technology, and it is NOT debateable! See, one problem is that contrary you your implication above, where you said that crypto policy becomes "politically debateable" (which implies that the ordinary people of a country have some input) the _reality_ is that any such decision will be made by a tiny number of bureaucrats, if they can get away with it. The US Clipper proposal was a classic example of this: There was absolutely no public discussion or debate on it before it was announced, and it was obviously intended to be a fait accompli. Further, nearly all non-governmental people who are aware of the crypto issue disagree with the government's policies in this matter. Clearly, you cannot imply that crypto will REALLY be "politically debateable"! >> For this kind of application, binding cryptography is spot on. >Jim bell[SMTP:jimbell@pacifier.com] wrote: >> I think the biggest problem with allowing "anyone" to check the >> correctness of a key is that what is a technical possibility today, >> will become a legally-mandated requirement tomorrow. What if >> Internet backbone companies and/or ISP's were told that they had to >> implement software check these keys, and if they discovered an >> "incorrect" escrowed key, they were legally obligated to either >> refuse to forward that message, and/or forward a copy of that >> message to someone like Spooks(a)NSA.gov or Thugs(a)DOJ.gov. > >The information society is international by nature; we want to >securely communicate with Singapore. If Singapore, a democratic >country!, has such a crypto policy that they want the above control, >then so be it. Don't blame "binding cryptography" for making that >possible, but start a dialogue with your politicians on what features >of the proposal are acceptable in your country. No, I think I _will_ blame your infernal invention for trying to make limited communication possible! There's no doubt that the leadership of places like Singapore might want to restrict communication, but on the other hand they also want to be connected to the rest of the world for "non-political" speech. In effect, they are forced to make a choice. Most countries, except for a very highly authoritarian few, will probably opt for connectivity and this will lead to increased freedom for the people in their countries. _YOU_ are trying to give those governments connectivity while maintaining tyranny. Are you proud of what you're doing? > >Some countries seem to have the philosophy that "law-abiding" citizens >should have nothing to "hide" from their government, so should not use >encryption at all. I think that that is not acceptable. The concept >behind the third-party checking is that no "law-abiding" citizen >should have any problem that abuse - and only that - of a *voluntary* >system can be "seen" by many parties. I think the terms "voluntary" and "abuse" are contradictory in your statement. If the system is "voluntary," then it is presumably "voluntary" to use a non-conforming system, right? And unless the government's goal is to harass or imprison or fine the user for not using that "voluntary" system, there is no purpose in knowing whether a person's use of encryption meets that "voluntary" standard. >If and *how* checking is >done, is a matter of each society. The same concept holds for many >things in life and is well accepted. I see: "How each society decides to use our thumbscrews is totally voluntary and up to each country!" Pardon me while I puke. > For instance that is why cars >have registration plates: if a car drives through after an accident on >a *public* road, then by-standers (third parties) can observe that. I >for one don't the information society to be the wild west, where >anything goes. I'm much closer to "the wild west" than you are, and I like it just fine. I prefer it much better than the tyranny of stratified societies that have enslaved people for over a thousand years. >Of course, people are rightfully worried that such a checkable system >might be abused by a totalitarian regime to control their citizens. >However, as long as such a system is voluntary I see no problem. Maybe you need to remember that the way governments use it, the definition of the word "voluntary" tends to pick up a rather Orwellian meaning. Also, you need to remember that the difference between a "voluntary" and a mandatory system may be as little as a single law passed in the middle of the night by a legislature. A law which you are intending to make possible! > Signs >in the USA indicate (cf. the NRC study & remarks of the president) >that use of other systems will always be possible. You seem to have ignored by conjecture, where I pointed out that Internet backbones and ISP might, hypothetically, be required to check keys and report "violations" to the government on a moment-to-moment basis. Further, they might be prohibited from forwarding messages that do not conform. This gets us back to the definition of the world "voluntary," again. Even if such an eventuality should occur, the government could cynically say that use of non-conforming forms of encryption were still "voluntary," because it's true you could use them. But they wouldn't be very useful if they didn't propagate on the Internet, now would they? >Also, the above >discussions already showed that if such a system is voluntary, then >there are lots of way to go around it. Not if the cooperation of everyone else is coerced! And moreover, not if they are coerced into not dealing with anybody who doesn't go along. You must really hate freedom, huh? Jim Bell jimbell(a)pacifier.com

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