December 2003 - cypherpunks-legacy

remailer questions
by Craig A. Johnston 17 Dec '03

17 Dec '03

Ok, I'm planning on putting up a remailer on my Linux box. One of the things I'd really like to know is, how much in the way of attempts to break into your machines are remailer ops seeing? How much in the way of other attacks? I'd also like to get some idea of the amt of resources consumed by a relatively popular remailer -- amt of system loading, disk space devoted to remailing activites, and anything else. I know loading will be hard to quantify in a meaningful way, but for reference my machine is a 486/66 w/32 megs RAM and pretty fast SCSI disks. Just a general idea of how significant the load on such a machine will be would be nice. My SCSI and Ethernet are both fast, and on a PCI bus. My site is at the moment, I think, relatively secure. I have few users and am sure at the moment nobody has an easily crackable password. I plant to install a fascist password checker soon. I currently have ftpd and fingerd commented out of my inetd.conf. (I plan to put ftpd back, at some point, but really don't like outsiders being able do a finger @site and find out who is on, how long, how long idle, find out when users last logged on or read their mail, etc. I will probably want to add it back after modifying it or finding a stock one that does what I want.) I have tcp wrappers installed, and have checked on a number of blatant security holes that I know of. I am worried that once I begin running a remailer, the number of attacks on my machine will increase dramatically. I'd of course like for my data and my users' data to remain private, and believe that a compromised remailer is (obviously) worse than no remailer at all. What would be nice, before I put up a remailer, would be to have any willing, security-knowledgeable cypherpunk subscribers out there to probe my machine for any really obvious chinks, for security-aware Linux users to point out any Linux or Slackware-specific security holes, etc. Of course I'd want to have a word with anyone willing to probe me before they just went at it... ;) Linux kernel is currently 1.1.81, which is quite stable for me, and the Slackware distribution is 1.2.0. I'm running sendmail 8.6.9, are there any really terrible vulnerabilities in it any longer from outside the machine? From inside? Of course, I'm on an Ethernet with others, and have users logging in from other Ethernets, so am vulnerable to sniffers. I don't think it's going to be feasible to install skey here, as a number of my users are extremely non-technical. I'm also still looking around for what I'm going to run. I'd like for it to be easy to reply to users, but absolutely impossible for me to 'out' anyone under any circumstances. The encrypted-sender stuff some remailers currently use is probably too ugly for most average joes to want to use, and not as secure as I'd like. It's probably the best available at the moment. This should definitely change. What I'd *really* like to do would be to write a client and server to make an anonymous pool act like normal email ... this is really the only way I can think of to make replying easy but also to have good security. I'm sort of surprised someone has not done this yet. It'd be pseudonymous, your client would only look at messages for you or for everyone (for your convenience -- of course anyone could look at anything, but it'll all be PGP'ed, so...) Some really neat things that could be done w/this... for folks willing to trust the sever to some degree, cross-referencing of pseudonyms and public keys could be done, allowing joe user to just mail to a pseudonym -- this would be good in cases where one party wishes to hide, while the other has nothing to hide and is possibly very non-technical. He'd have no guarantee that someone wasn't reading his mail to the pseudonymous party, on the way in, but the p.n. party would not have to worry about having his real address cross-referenced, or about the server having the key to decrypt his real (included) address in memory or on disk. Anon pools are obviously doable right now, with a mailing list, but the inconvenience of using one like this is a real barrier. An anonymous pool; Usenet-like -- distributed over many machines in many countries, but with pseudonyms instead of "real names" and public keys as addresses. This is definitely doable, right now. NNTP-type servers doing news and mail service. As the scale got larger, we'd of course not want to send everyone's mail to all the servers, but tying a user down only as far as to a given server would probably not be a problem -- look at all the different folks that may use one NNTP server. Perhaps mail for a given user could be sent to several different servers to keep things muddy. Mixmaster does not currently run on Linux, is that correct? Anyone know what the problem is, or have an idea what amt of work would be involved in porting it? I'd like to look at this. Really, though, everything out there is pretty unsatisfactory -- only anonymous pools and DC-nets have the characteristics I'm interested in. Anyone on the list doing any serious work on DC-nets? I find these extremely exciting, and don't see much brainstoming on implementation going on. regards, Craig.

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Re: T.A.Z. on Disk
by Angus Patterson 17 Dec '03

17 Dec '03

On Fri, 20 Jan 1995, Charles Bell wrote: > > > > The book "Temporary Autonomous Zone" is available online at wiretap.spies.com > > Available how, exactly? Sorry about that. The hazards of being brief, I guess (never post when you're half asleep). Gopher and ftp work for the same address on this one. /Library/Documents/taz.txt is good for ftp, or try the /Electronic Books at Wiretap heading on the first menu, if you use gopher. The pointers to the other etext sites might lead you to his other stuff (there were two others as far as I can remember).

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Crypto Anarchy/Libertarians in WSJ
by frissell＠panix.com 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Today's WSJ Front Page Left Column Less Is More Libertarian Impulses Show Growing Appeal Among the Disaffected When the Government Fails Many Voters are Asking: Who Needs it Anyway? Mixed Blessing to the GOP "Mr. Frezza...doesn't just want to cut government: He questions the very need for most of it. He figures that in a world in which computer wizards are close to creating their own private, encrypted digital cash system for making transactions without any government involvement, the need for centralized authority is shrivling." DCF -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQCVAwUBLx/FiIVO4r4sgSPhAQEhmgP/dxCXAPS6iu/Zb9P7AuC6D8aDg94vZABs VjlXXXXWjkHedveIjQ9qdU8xELblzZiMlu35SKKygLvsD2a8bNXiC2FxBnA/H716 Dj4UHksctV3wJSZuwq6z8/fZds0Dg5GJLYbAUrbdInp/tM7TMrAhUVLFVkVpzhzk 25aXzmIiv5U= =4FOR -----END PGP SIGNATURE----- ************************************************************************* ATMs, Contracting Out, Digital Switching, Downsizing, EDI, Fax, Fedex, Home Workers, Internet, Just In Time, Leasing, Mail Receiving, Phone Cards, Quants, Securitization, Temping, Voice Mail.

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Re: T.A.Z. on Disk
by dmandl＠bear.com 17 Dec '03

17 Dec '03

> From: blancw(a)pylon.com > > *T.A.Z. = The Autonomous Zone T.A.Z. = Temporary Autonomous Zone --Dave.

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Re: T.A.Z. on Disk
by dmandl＠bear.com 17 Dec '03

17 Dec '03

There's a Hakim Bey web site with the full text of TAZ and a bunch of other things, including the pamphlet "Radio Sermonettes" and various other essays. I've got the URL at home, so I can post it to the list tonight (sorry, but it's easier than asking people to email me for it individually). The text, at that site at least, is the absolutely authorized original (from our original files). I've got other odds and ends by H.B. that have never been made available on the net which I may or may not get around to posting in the next few weeks. The followup to TAZ (the book), which will probably be called "The No-Go Zone," will be out in about six months. Well, maybe nine... --Dave. > From: Angus Patterson <s675570(a)aix1.uottawa.ca> > > On Fri, 20 Jan 1995, Charles Bell wrote: > > > > > > > The book "Temporary Autonomous Zone" is available online at > wiretap.spies.com > > > > Available how, exactly? > Sorry about that. > The hazards of being brief, I guess (never post when you're half asleep). > Gopher and ftp work for the same address on this one. > /Library/Documents/taz.txt is good for ftp, or try the > /Electronic Books at Wiretap heading on the first menu, if you use > gopher. The pointers to the other etext sites might lead you to his other > stuff (there were two others as far as I can remember).

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Re: T.A.Z. on Disk
by Mark Grant 17 Dec '03

17 Dec '03

On Fri, 20 Jan 1995, Angus Patterson wrote: > I also saw another e-book site that had some more of his stuff, can't > remember what it was though. There's some more on the WWW at http://www.uio.no/~mwatz/bey/index.html. Mark

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Re: T.A.Z. on Disk
by John Young 17 Dec '03

17 Dec '03

On Fri, 20 Jan 1995 Mark Grant <mark(a)unicorn.com> said: Another source is via Nesta Stubbs inspirational home page: http://www.mcs.com/~nesta/home.html The NO address is referenced by Nesta, stylistically inimicably.

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And another thing (Hakim Bey)
by dmandl＠bear.com 17 Dec '03

17 Dec '03

Also, the current issue of "Axcess" magazine (a slick cyber-zine) has an interview with Hakim Bey in which he mentions the cypherpunks as one of the few groups doing something worthwhile in cyberspace, or words to that effect. I'd post the short passage, but the copy emailed to me by the editor was garbled (heh). --Dave.

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Re: Remailer-on-a-CD
by jalicqui＠prairienet.org 17 Dec '03

17 Dec '03

Ed wrote: >If you look out on ftp.netcom.com:/pub/ec/ecarp/linux*, you'll find a bare- >bones Linux set that will install right in a DOS filesystem (it's a .ZIP file). >It's intended for SLIP clients, but it could easily be adapted for setting >up an "instant remailer". I saw your announcement on comp.os.linux.announce right after suggesting the "instant remailer" idea. (what timing!) Already got it, and plan on playing with it a little bit to see what fun we could have. (5-floppy remailer install, anyone?)

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Re: traffic analyzing Chaum's digital mix
by Hal 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- From: Wei Dai <weidai(a)eskimo.com> > I have been thinking about the problem of traffic analysis of a > remailer. > [...] > The basic approach is to use this raw traffic information to calculate a > SCORE for each user of the remailer with respect to Alice, where the > user with the highest SCORE is the person Alice is most probably > communicating with. The idea is that with a Chaumian mix, every time > Alice sends a message to Bob there is always a pattern of Alice sending > a message to the mix, followed by Bob receiving a message from the mix > during the next batch. By counting the number of such correlations for > each user over a period of time, and taking into account the fact that > users who receive more messages from the mix will have higher numbers > of coincidental correlations, a SCORE can be calculated so that it would > be a good indication over the long run of the probability that a particular > user is communicating with Alice. This sounds like a good idea. It was very interesting to see your earlier result on the impact of dummy messages on this approach. Even a relatively small number of batches without dummy messages allows continual accumulation of incriminating information. I know that the Eurocrypt 89 proceedings had some articles on cryptanalyzing Chaum's mixes. My library has an excellent crypto selection but is missing this volume. Can anyone who has read this say whether there is anything in those papers that isn't obvious? Another interesting aspect of your analysis is the possible role of latency. Earlier I had thought of latency as primarily a way of doing mixing, an alternative or addition to batching which mixes messages without holding them up quite as much. But in terms of this in/out analysis latency could play a part in blurring the batch boundaries, adding more uncertainty and making the job of the analyst harder so he would need more data to establish his scores. Hal -----BEGIN PGP SIGNATURE----- Version: 2.6 iQBVAwUBLx/jixnMLJtOy9MBAQGFzwH/diYW0NSddacKyXGvsBc53FsR47R+4BSS pVprHz2LfpVl7U2FFAePMjZIGr5w24hA6nxn1brAO9v6JkVzgUabvA== =Vehs -----END PGP SIGNATURE-----

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