December 2003 - cypherpunks-legacy

Simplified Digital Postage--Proposal
by tcmay＠netcom.com 17 Dec '03

17 Dec '03

In the aftermath of the "Valentine's Day Massacre," the need for some form of digital postage is more apparent than ever. In this note, I propose an extremely simple system, based on the selling of numbers as "coupons," redeemable for "passage" through a remailer. A more sophisticated system based on true digital cash, perhaps based on Magic Money," is more desirable, but almost anything is better that the current system. (Well, not _anything_.) Seeing the huge list of newsgroups that Detweiler attempted to post to, I conclude that some form of "rate-limiting" function is needed. In general, not just for Detweiler in particular. Not posting quotas, not even source-level blocking (though in Det's case, this is justified as a stop-gap measure), and not even "outgoing moderation" (in which someone like Hal would scan the plaintext of outgoing messages, briefly, to see if the text was malicious, dangerous, etc.--not a great idea, for many reasons). I propose remailers immediately adopt some form of digital money/postage, even if current instantiations are not fully debugged or optimized. "Magic Money" may be ready for such a trial use. Advantages: - causes those who wish to "flood" (cf. Hal's huge list) to at least pay for the flooding - is an immmediate use for a crude form of digtial money, a test bed for ideas and a stimulus for new features, improvements - is "voluntary": those remailers who don't wish to bother with this digital postage can then get the heavy volume of flooders! - subtle flaws in digital money protocols (and I doubt "Magic Money" is completely free of subtle or not-so-subtle flaws...everything needs debugging and evolutionary learning) will not be so serious when only "postage" is involved. As opposed to "real money" situations, where finding a way to break or spoof the protocol could result in large amounts of money being lost. At least with digital postage, about the worst that could happen is someone gets free remailing--the current situation. - the experimental use would take place with "remailer-savvy" users, which is better than trying to educate the outside world at this time - and of course, a charge of, say, $2.00 in real money (send in $20, get bact 10 remailer "stamps" of some form, suitably anonymized through a blinding procedure a la Chaum) would mean that posting to 20 newsgroups would be a nontrivial expense for a would-be flooder. (Actual rates would vary, as determined by the market and by the willingness of a remailer operator to put up with the kinds of hassles Hal is now seeing. I won't presume to speculate on the likely price of a stamp. It would depend on the destination. I know, for example, that I'd be willing--if I ran a remailer--to remail small items to single destinations for a lower fee, perhaps for free, than I would to mail large items to mail-to-Usenet gateways!) How ready is Magic Money for a test-bed use like this? How willing are remailers to try this? Both Hal Finney and Karl Barrus have code for remailers (Karl's is more recent, Hal's is in wide use). Could their code be modified easily to accomodate a primitive form of stamps? Could such stamps be sold in a reasonable way? Simple-minded approach to digital postage stamps: In my simplistic view, which I proposed a while back, stamps are merely 20- or 30-digit numbers. Imagine someone going to a Cypherpunks meeting with a box of these numbers, printed on slips of paper. For $10, say, one can reach in to this box and take out, say, 20 stamps. The seller doesn't know who got what stamps, so long as enough are sold, and he "honors" a stamp when the appropriate number is included in a message. For example: ::Stamp 29038571037489236478380016283 ::Request-Remailing-To: foo.bar etc. The stamp selling process could be computerized, but more sophisticated means of ensuring tracking is not done would have to be use (e.g., blinding, or multiple resellers). Can random guesses be made? Not feasible, with 20- or 30-digit numbers. Can the stamp seller repudiate or not honor a number so as to cheat the purchaser? Sure, but that's not a viable long term business. And word would get out. Some folks might report regularly on "remailer reliability," a la the "ping" reports several folks have issued. Reputations matter. Can the same number be used twice? Not if the remailer removes the number from his list of "sold" numbers. (This assumes each number or stamp is specific to some remailer, the easiest case to handle. Having "global" stamps complicates things greatly and introduces the expected issues of database synchronization, clearinghouses, fraud, etc. This is why "coupons" are easier to make than "currency." What do you folks think? Seems to me we could deploy a fairly simple digital postage system quickly. This could begin to immediately cut down on flooding attacks on the remailers. --Tim May -- .......................................................................... Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay(a)netcom.com | anonymous networks, digital pseudonyms, zero 408-688-5409 | knowledge, reputations, information markets, W.A.S.T.E.: Aptos, CA | black markets, collapse of governments. Higher Power:2**859433 | Public Key: PGP and MailSafe available.

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For those biting at the bit (or byting at the bit)
by Matthew J Miszewski 17 Dec '03

17 Dec '03

Glad to see cpunks back to crypto talk. Anyways, to those of you who are anxious to see crypto applied in a larger arena, your opportunity might be coming soon. A few months back I announced that I will be starting a Data Security Corporation which will apply and develop crypto protocals. To all those who have been inundating me with questions, they will be answered very soon. I have been *very* busy, but the work is coming along fine. So, if you are interested in getting involved, or if you would no longer like to be contacted about it, let me know. A general message will go out by the end of the week. Personal replies and requests closely following. To all those who have already responded I am sorry that it has taken this long. I want to do this right. I appreciate your enthusiasm. Now lets make it pay off. Cypherpunks form Corporations! --Matt ______________________________________________________________________________ In defense of liberty, encrypt for all purposes, civil and professional. In defense of privacy, encrypt all correspondence, personal and professional. In defense of sanity, do not encrypt your dry cleaning invoice! ++++++++--------mjmiski(a)macc.wisc.edu (c)1993

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Re: Where to get Big Bro Stickers
by James Still 17 Dec '03

17 Dec '03

>On Mon, 14 Feb 1994, Eric Hughes wrote: > >> Will someone put a few "Big Brother Inside" stickers inside a stamped >> #10 envelope and snail-mail it to Safire? >> >> It _will_ get mentioned in a column. > >Where can you get these stickers? I sent my donation to: Christian Douglas Odhner 14079 N. 34th Place Phoenix, AZ 85032 cdodhner(a)indirect.com But beware! I sent him $15 bucks about 6 months ago and have yet to see any stickers in the mail... Perhaps I'll try e-mailing him again to see what's up; or perhaps I should acknowledge a beautiful scam when I see one! (Or maybe the elusive tentacles have struck down another pesky cypherpunk...)

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Re: Detweiler remailer abuse
by lefty＠apple.com 17 Dec '03

17 Dec '03

Xenon, who shows a surprising depth of introspection in styling hirself after an element which is both gaseous and inert, writes: > >I can't take life seriously enough to censor old Larry. I suggest a short chat with Mr. Dictionary to determine the actual definition of the word "censorship". In the immortal words of Inigo Montoya, "You keep saying that, but I don't think it means what you seem to believe it does." >I can't take the IDEAL of the First Amendment lightly >enough to do so either. OK, I see we can add the First Amendment to the list of subjects on which you are essentially totally ignorant. When you finish with Mr. Dictionary, you might try puzzling out Mr. Bill of Rights. _It_ doesn't say what you apparently think it does, either. >And afterall, he wasn't the one who wrote that "Blacknet" blurb. Was there a point to this statement? Other than the one athwart your knotty little cranium, I mean. If so, it utterly eludes me. Do you believe that drunk drivers should not be held responsible for their actions because they don't build their own cars? >I find it amusing to see uptight fuck-wads from specialized narrow minded >Usenet groups yelling about someone sending something to >their precious little group that upset them. Not nearly as amusing as _I_ find it to see know-nothing children attempting to impress the big kids with their general level of uninformedness. >Abuse away Larry. Show us that we really DO need dumb optical fibers >between laptops instead of this tight-assed RFC standardized >World Wide Wiretap we call our playground. We need a new >net guys. Please feel entirely free to avoid using the old one while you wait patiently for the new and perfect one to show up. I suggest you avoid posting any further until you have _real_ _encryption_ running in your laptop and _optical_ _fiber_ connecting you to all the places with which you might consider communicating. -- Lefty (lefty(a)apple.com) C:.M:.C:., D:.O:.D:.

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Re: Clipper and Traffic Analysis
by Peter Wayner 17 Dec '03

17 Dec '03

I believe the LEAF field is useful, but not too useful. Here are my points: *) It helps in unauthorized taps. I would presume that the police won't have access to the phone company's calling records if they're just using a pair of alligator clips. *) On the other hand, the system really isn't anywhere near as useful as the phone number of the person calling. There will be no map between LEAF id numbers and people. Such a map would quickly get out of date as people traded phones etc... *) It might be slightly better than the phone number in strange cases because it identifies the handset not the number. Who knows? Phone calls from the garage extension mean one thing but phones from the kitchen extension mean another. This might be significantly more important if businesses private exchanges don't release the internal extension making the call.

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Re: Detweiler abuse again
by Hal 17 Dec '03

17 Dec '03

I understand Eric's comments about the use of logging to "catch" Detweiler in the act here. Frankly, I expected more criticism of that action than I received. I should make it clear that I do not routinely log, but that after receiving the complaints I forwarded to the list I added a line to my maildelivery file to save all messages with the same subject line as the offending message to a file. Within minutes, the message from Detweiler appeared. I'm not sure Eric's idea about connecting via sockets would eliminate all possibilities of logging. It seems that with telnet, at least, the systems that you connect to are able to find your host name. Still, host names would be more private than full addresses. Grepping the Blacknet log file for "request-remailing-to" shows the following messages which have accumulated overnight: request-remailing-to: comp.sys.ti.explorer(a)news.cs.indiana.edu request-remailing-to: rec.mag(a)news.demon.co.uk request-remailing-to: rec.sport.football.australian.usenet(a)decwrl.dec.com request-remailing-to: alt.fan.addams(a)news.cs.indiana.edu request-remailing-to: soc.history(a)news.demon.co.uk request-remailing-to: comp.archives.msdos.d(a)news.cs.indiana.edu request-remailing-to: rec.pets.dogs.usenet(a)decwrl.dec.com request-remailing-to: comp.sys.sgi.graphics.usenet(a)decwrl.dec.com request-remailing-to: alt.fan.vejcik(a)news.demon.co.uk request-remailing-to: alt.fan.addams(a)news.cs.indiana.edu request-remailing-to: rec.pets.dogs.usenet(a)decwrl.dec.com request-remailing-to: alt.abortion.inequity(a)news.cs.indiana.edu request-remailing-to: alt.security(a)news.demon.co.uk request-remailing-to: alt.sports.football.pro.dallas-cowboys.usenet(a)decwrl.dec.com request-remailing-to: rec.music.classical.guitar(a)news.cs.indiana.edu request-remailing-to: news.announce.important(a)news.demon.co.uk request-remailing-to: misc.health.alternative.usenet(a)decwrl.dec.com request-remailing-to: alt.beer(a)news.cs.indiana.edu request-remailing-to: alt.archery(a)news.demon.co.uk request-remailing-to: alt.sports.basketball.nba.wash-bullets.usenet(a)decwrl.dec.com One good thing is that he is apparently targetting just a few mail-to-news gateways. I was worried because one of the complaints I got came from a mailing list; it would be completely infeasible to block all mailing list addresses. But blocking the mail-to-news gateways would be pretty easy. (As an aside: how do these gateways take the heat? Should I suggest to those complaining to me that my system is intended for email, not usenet, anon- ymity, and that they should direct their complaints to the mail-to-news gateways which are the "real" cause of the problem? Is this tactic likely to be politically effective?) Now, I haven't received any complaints from the administration at this commercial system for which I pay about $30 a month. In fact, I have never received any complaints about my remailer from the admins, even though I assume that at least some complaints have been sent to root or postmaster here. I know that the owner of the Portal system was at the hacker's conference a couple of years ago (according to a report on the cp list), and that he supposedly pledged his commitment to the concept of anonymous remailers. I have never contacted him, but perhaps I am protected to some extent by his beliefs. At this point, I will probably take no action and see if this blows over. If I get more complaints, though, I will probably block the mail-to-news gateways as outgoing addresses. Another alternative would be for me to forward outgoing mail which is directed to the mail-to-news gateways through another remailer, such as Xenon's at netcom.com. Thanks for the suggestions and advice. Hal

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DOS Stego?
by Bruce C. Dovala 17 Dec '03

17 Dec '03

Does anyone know of a steganography program for DOS? Thanks, Bruce

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Re: LEAF, SS7
by smb＠research.att.com 17 Dec '03

17 Dec '03

The LEAF has many very interesting attributes. As I mentioned earlier, in response to Mike's original question -- yes, there are tremendous advantages to the LEAF for a traffic analyst. But the LEAF itself is encrypted, including the session key, so enemies can't do traffic analysis based on the LEAF. The structure of the LEAF is also a dead giveaway that Clipper is being used -- it's easy to envision a box that has the family key, and tries every LEAF-sized field to see if it decrypts to something that looks right, and in particular has the right checksum. It detects Clipper -- and coupled with a random sequence detector, it detects encrypted, non-Clipper traffic...

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Re: LEAF, SS7
by m5＠vail.tivoli.com 17 Dec '03

17 Dec '03

smb(a)research.att.com writes: > But the LEAF itself is encrypted, including the session key, so > enemies can't do traffic analysis based on the LEAF. "Enemies"? Isn't that a subjective term? :-) > The structure of the LEAF is also a dead giveaway that Clipper is > being used -- it's easy to envision a box that has the family key, > and tries every LEAF-sized field to see if it decrypts to something > that looks right, and in particular has the right checksum. I'm going to make the almost certainly valid assumption that you know more about the way the network works than I do, but my assumption is this: in the wacky scenario I described wherein Clipper devices are installed in the network interfaces "everywhere", then the presence of these identifiable (and identifying!) packets means that a central tap at a regional switching center could concievably perform traffic analysis without the need for taps on local loops anywhere. Is this assumption way wrong? -- | GOOD TIME FOR MOVIE - GOING ||| Mike McNally <m5(a)tivoli.com> | | TAKE TWA TO CAIRO. ||| Tivoli Systems, Austin, TX: | | (actual fortune cookie) ||| "Like A Little Bit of Semi-Heaven" |

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re: LEAF, SS7
by koontzd＠lrcs.loral.com 17 Dec '03

17 Dec '03

> It might even be that Clipper hardware could be >installed right at the network interface. Isn't that nice, the phone >company is going out of its way to safeguard my privacy. Only thing >is, now every circuit I establish is tagged by an LEAF that identifies >me... Actually, providing link encryption via CLIPPER only allows identification of the link, still useful in traffic analysis. (As a quick means of identifying the link.)

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