December 2003 - cypherpunks-legacy

Re: Why can't I get PGP from MIT
by Lou Zirko 17 Dec '03

17 Dec '03

I have sent two requests myselt in the last two months that have gone unanswered. The request was to have isdn.net added to the allowed list. I know the initial rejection was the .net domain, but the location should not be hard to look up - just a basic whois. I got PGP from alternative locations, but still have not been able to get PGPhone. > MIT won't let me get PGP or PGPhone. I know their server > went down awhile back but, I have tried them several times > and sent several e-mail requests. I thought maybe I was > missing something obvious or maybe they are just really > busy. I keep being told I'm not in the U.S. <snip> > All I want is clean copy of PGP for personal use. I have considered > purchasing a commercial system but still would like to try PGP with > the big keys. > > Thanks, > Sid Post > post(a)why.net > > > Lou Zirko (615)851-1057 Zystems lzirko(a)isdn.net "We're all bozos on this bus" - Nick Danger, Third Eye -----BEGIN PGP PUBLIC KEY BLOCK----- Version: 2.6.2 mQCNAzBLJocAAAEEAMlDzYJPYq0pvfMuSiKU0Y65L2nJql+qEJHYGjO5Pys4prDw YW1ooPWaqrPQAy/eyqrM7I9KNFDCtmaPxtgcPw2oEDfc/w6cPkrVzvovKLfHQvtg V/hHUekptSf6j525omrVAoM9MxVL3sEGCjn9VrTeC3h9upkfntHOJeL88i2NAAUR tB5Mb3UgWmlya28gPHppcmtvbEBkYXRhdGVrLmNvbT4= =Qlxm -----END PGP PUBLIC KEY BLOCK-----

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Re: Internet & Porno on A&E tonite
by wlkngowl＠unix.asb.com 17 Dec '03

17 Dec '03

On Sat, 6 Jan 1996 10:54:55 -0600 (CST), you wrote: >Hi, >Just saw an add for a Investigative Reports show tonite on A&E dealing with >the Internet and some of the current issues relating to porno and privacy. What time?!?

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"trust management" vs. "certified identity"
by Matt Blaze 17 Dec '03

17 Dec '03

The discussions here of the limits of PGP's certification and revocation model are close to the core of some work I've been doing (with Joan Feigenbaum and Jack Lacy) on what we call the "trust management" problem. Essentially we consider the consequences of abandoning the notion of "certified identity" implicit in systems like X.509 and PGP and subsuming identity under the more general umbrella of specifying and determining what a key is trusted to do. We've built a system, called "PolicyMaker", that allows the certifier of a key to specify what the key is trusted to do rather than to whom the key is trusted to belong. The same mechanism is also used to specify and interpret local policies. The PolicyMaker system is designed to be called as a service by local applications, which could be email systems like PGP or network-layer security protocols or any other application that requires complex trust relationships. Some early, local experience suggests that this approach is a good one. It's easy to specify X.509- and PGP-style policies and certificates, but you can also say things like "valid for transactions over $500 only if countersigned" in a fairly natural way. I'll be happy to send a (very early) draft of our paper, "Decentralized trust management" to anyone who's interested. I've made the draft available in the CFS-users email archive server. To request a copy (PostScript format) by email: echo get cfs-users pmdraft.ps | mail cfs-users-request(a)research.att.com (For non-unix shell people, just send a message to cfs-users-request(a)research.att.com With the line: get cfs-users pmdraft.ps in the BODY of the message (NOT on the subject line).) Comments and discussion appreciated. This is an early draft, and I'd appreciate it if it not be directly quoted, cited, or re-distributed. -matt PS We expect to give away our reference implementation, too. (Probably by May or so.) Note that this is just research, and does not represent any current, past, or future product or service offering on the part of AT&T or anyone else.

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RE: Revoking Old Lost Keys
by Frank O'Dwyer 17 Dec '03

17 Dec '03

On Saturday, January 06, 1996 09:18, Timothy C. May[SMTP:tcmay@got.net] wrote: >At 7:07 AM 1/6/96, Bruce Baugh wrote: >>I'd like to bring up a problem I haven't seen addressed much yet, and which >>I think is going to come up with increasing frequency as PGP use spreads. >> >>The problem is this: how can one spread the word that an old key is no >>longer to be used when one no longer has the pass phrase, and cannot >>therefore create a revocation certificate? > >Basically, you are screwed. Any revocation you attempt will not be trusted, >as we will suspect the new "you" to be an attacker, perhaps an agent of the >NSA or the Illuminati. In the view that "you are your key," the old you no >longer exists. This is true, but the "old you" can be resurrected if you can get enough people to believe your new key using any out-of-band means available to you. You can also put a comment in your new key's uid explaining the problem and how to verify the new key. You will find it very hard to use this new key for a while, though, during the transition period. Many people will take the existence of two keys with the same uid as suspicious in itself, since it at least indicates some kind of attack (even if only a denial of service attack). This is really a usability flaw with current PGP. The PGP formats do allow for a 'revocation' certificate, but PGP doesn't implement it (yet, I guess). In any case, it's not really strong enough, since what it says is "I retract all my previous statements that this key is related to this user". This'd mean that you'd have to visit everyone who'd ever signed your key and get them to issue this retraction. What would be needed for this problem is either an "anti-certificate" ("This key does not belong to this user"), or else some convention. For example, if two _trusted_ keys are found for the same uid, the most recent one could be chosen, and the earlier one be purged from keyservers, etc. This may be possible with current PGP. I haven't tried it, but since I have some keys which have fallen into disuse, I will need to do so sometime.). Cheers, Frank O'Dwyer fod(a)brd.ie http://www.iol.ie/~fod

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please stop the Mitnick stuff
by Perry E. Metzger 17 Dec '03

17 Dec '03

This is cypherpunks, not Mitnick punks, Shimomura punks, or anything similar. I personally don't care about Kevin Mitnick, and he most certainly has little to no cryptography relevance at this point. Take it elsewhere. Perry

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RE: Revoking Old Lost Keys
by frantz＠netcom.com 17 Dec '03

17 Dec '03

Perhaps if keys could be made with expiration dates (certificates too), this problem might be reduced to managable proportions. ----------------------------------------------------------------- Bill Frantz Periwinkle -- Computer Consulting (408)356-8506 16345 Englewood Ave. frantz(a)netcom.com Los Gatos, CA 95032, USA

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Re: please stop the Mitnick stuff
by nobody＠REPLAY.COM 17 Dec '03

17 Dec '03

At 06:31 PM 1/6/96 -0500, Perry Metzger wrote: > >This is cypherpunks, not Mitnick punks, Shimomura punks, or anything >similar. I personally don't care about Kevin Mitnick, and he most >certainly has little to no cryptography relevance at this point. Take >it elsewhere. C'mon, Perry, give it a break. Mitnick's case has to do with security issues as well as the violations of privacy and/or search and seizure the government used to arrest him. It may not be cryptography per se, but are you going to seriously argue that security, etc. is not encompassed in crypto issues? I found it interesting. If you didn't, then all you had to do was delete it. No one needs to read your personal crusade as *The One* who tells us what's relevant and what's not.

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RE: Revoking Old Lost Keys
by Frank O'Dwyer 17 Dec '03

17 Dec '03

On Saturday, January 06, 1996 07:19, Timothy C. May[SMTP:tcmay@got.net] wrote: >At 9:47 AM 1/6/96, Frank O'Dwyer wrote: >>On Saturday, January 06, 1996 09:18, Timothy C. May[SMTP:tcmay@got.net] wrote: > >>>Basically, you are screwed. Any revocation you attempt will not be trusted, >>>as we will suspect the new "you" to be an attacker, perhaps an agent of the >>>NSA or the Illuminati. In the view that "you are your key," the old you no >>>longer exists. >> >>This is true, but the "old you" can be resurrected if you can get enough >>people to believe your new key using any out-of-band means available >>to you. You can also put a comment in your new key's uid explaining the > >Could you explain how "enough people" can get around a basic >feature/limitation of the current PGP web of trust? Who, besides the >originator, can revoke an old key? How many does it take? I wasn't referring to revoking the old key, but to introducing a new one and letting the old one fall into disuse. I think this can sometimes be done even if you've lost access to the old key, albeit in a painful out-of-band fashion. It does depend on the application, though, and if the (relevant portion of the) web of trust was very large, you might find that the old key kept popping up and you kept getting mail (or whatever-it-is-you're-encrypting) that you couldn't read. (and/or some people wouldn't believe your signatures). Basically, PGP's revocation model is broken unless you create a revocation cert. at the time you make your key, and keep it safely somewhere in case you need it. Even then, as time goes by the keyring keeps accumulating all these extra packets and growing without bound. It's not just PGP--all long-lived certificates are hard to revoke (for example X.509's revocation is also clunky). It's just that PGP's certificates are particularly long-lived, and PGP's revocation is particularly broken. Luckily the data formats do allow for a validity time, and a revocation of a key's countersignature, so this can perhaps be fixed sometime. >If a bunch of the "alleged" friends of Bruce could do this, could they not >revoke the key of someone they simply wish to hassle? Well, see above. The key is not revoked. But a bunch of people _could_ attempt to introduce a key under the name of someone they just wanted to hassle. The conspiracy doesn't have to be especially large. For example, it would be easy for me to invent a key for you and have _my_ friends believe it even in spite of your real key being on their keyrings. It wouldn't be so easy for me to get _your_ friends believe it. In Bruce's case, he'd be trying to do a similar thing, except that the key'd really be his, and more people'd be likely to believe him (especially his friends, and their friends, and so on). >I agree that a new key can be generated, and a new "Please use this key, >not the other one" message sent, and this may work, but I don't believe >this revokes the old key and removes it from the keyservers. I could be >wrong, as I am certainly no expert on the keyservers. I think you're right. The key will still be out there. >The question is: is there a "majority vote" mode on the keyservers that >causes them to remove a key if enough people claim it is no longer valid? I don't think so. At best, you might be able to convince the admins to manually delete the old key from the server's rings (assuming the software is able to do this). Even then, the key might keep popping back up, for example if you had countersigned other people's keys with your old key and they kept uploading their key with additional signatures. A practical solution might be for the key servers to automatically remove keys older than X years (or some time limit related to the key size). Ultimately though, what is needed is a new revocation model (maybe implementing the unused fields in the PGP certs is good enough to begin with). Cheers,Frank O'Dwyer fod(a)brd.ie http://www.iol.ie/~fod

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RE: "trust management" vs. "certified identity"
by Frank O'Dwyer 17 Dec '03

17 Dec '03

On Saturday, January 06, 1996 10:32, Matt Blaze[SMTP:mab@research.att.com] wrote: >The discussions here of the limits of PGP's certification and >revocation model are close to the core of some work I've been doing >(with Joan Feigenbaum and Jack Lacy) on what we call the "trust >management" problem. > >Essentially we consider the consequences of abandoning the notion >of "certified identity" implicit in systems like X.509 and PGP and >subsuming identity under the more general umbrella of specifying >and determining what a key is trusted to do. This is an interesting idea. I think, though, that there's something to be said for keeping identity and privilege separate things to be vouched for. For one thing privileges and policy change but identity doesn't. Privilege is also relative, but identity is not (nyms and that aside). I'm Frank O'Dwyer anywhere I go, but I'm not "loyal bank customer" to all banks. Also, it's easier to securely determine that I'm Frank O'Dwyer than it is to securely determine (say) my credit limit. So, a signator's job in signing for my identity is easier (and less risky) than signing for my trustworthiness. And we still don't have many CAs signing for identity! Plus, given secure identity (which might be an anonymous id), you can layer the other stuff on top. That's not to say that the certification approach can't be general, though. It occurred to me that a very general certificate format would simply be to sign some assertions (predicates), and then feed all available signed predicates plus some axioms (the analogue of root keys) into a theorem prover. Sounds slow though. More practically perhaps, you could sign some kind of (safe) interpreted code, and have the verifier execute it on some initial variable set to come up with some access decision. I haven't read your paper yet though! I'll read it and get back to you. There does seem to be something about current models of certification that inhibits their take up, so it's good to hear something new in this area... Cheers, Frank O'Dwyer fod(a)brd.ie http://www.iol.ie/~fod

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Re: Mixmaster On A $20 Floppy?
by loki＠obscura.com 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- The second paragraph of this post seems to address a different issue than the first. The problem of correlations between a certain sender sending and a certain receiver receiving, is well known and understood. The best defense against this (as a sender) is to send messages into the remailer network with a period equal to or less than the the time required for a message with your typical chain length to pass through the remailer net. If these are sent at random intervals, then your real mail will blend with the cover traffic, and mail from you will correlate with all message receipts by all message recipients. The second paragraph seems to deal with the issue of being known as an anonymous remailer or regular remailer user. I am not sure exactly what the concern with that is. -Lance At 11:56 PM 1/5/96, Futplex wrote: >The "ultimate" traffic analysis problem, as others have observed, is >the correlation between messages sent by A and received by B via the overall >network. Hence the utility of a Dining Cryptographers' Net, PipeNet, etc. in >which the apparent bandwidth variation between any two points is eliminated. >A and B are effectively folded into the network. > >I suppose that a site that escapes detection as a Mixmaster will throw off >the correlation stats (i.e. because a message from that site to B won't be >identified as a remailed message). But such sites are elusive objects I >think. On the one hand, the site can't endure for long, or else its >throughput traffic will likely give it away as an anonymizer (i.e. it gets >lots of mail from the Mix network, and sends out similar amounts of mail to >all sorts of people and the network). On the other hand, it had better last, >or else it will look suspicious as a transient account receiving mail from >the Mix network, sending a few messages, and quickly vanishing. > >Futplex <futplex(a)pseudonym.com> >"Dammit Jim, I'm a doctor, not a bricklayer!" > -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQEVAwUBMO9nDfPzr81BVjMVAQF1YQgAo08ndnu7Lcok3O12hCYz57j+PClp8ulk LRRGGejhTNerums+FInio2IUQK3YvWLsIUj+UkZZkYPGAV292AsKnQROzBAYZ2kd V8MdVUqolZQfFzR7VYS2n+6ARlplff0E+58X2NDHgw25welmg7Id/xJmjiIwHI8J U6eGUw0BhMKrQuXCv4NpUsYGC2ux2abOs+Y2f4pjzSSyJhLuAXJbzlr0eRYWPOj7 AU2AAs/l4xTGbErYc2F5D9pfTJe6sMkUCseIyVpsoLUMsg24LItlDOUq1feT2ppq X1LJQRu05ERt3LIhjB5JHFClxecQyw31JDZV8E2H19mawK1LIkgKNA== =MU1s -----END PGP SIGNATURE----- ---------------------------------------------------------- Lance Cottrell loki(a)obscura.com PGP 2.6 key available by finger or server. Mixmaster, the next generation remailer, is now available! http://obscura.com/~loki/Welcome.html or FTP to obscura.com "Love is a snowmobile racing across the tundra. Suddenly it flips over, pinning you underneath. At night the ice weasels come." --Nietzsche ----------------------------------------------------------

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