December 2003 - cypherpunks-legacy

Re: Encrypting block driver for Linux...need some advice
by Johnathan Corgan 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- On Wed, 26 Jul 1995, Tatu Ylonen wrote: > How about using the md5 hash of the block number combined with some > secret data; e.g, the md5 hash of the passphrase reversed (I would not > want to use the password directly, as that might help in breaking the > key; on the other hand, md5 of block number alone is not good because > there is a very limited number of blocks (and the attacker knows which > block is being attacked)). I guess my question is how does knowing the IV affect the security of CBC? I assumed that it only needed to be different for each block so that identical plaintext encrypts to different ciphertext for different blocks. > You might also want to support other algorithms, particularly IDEA > (but beware, IDEA is patented and causes problems for commercial use - > non-commercial use should be free). Another algorithm to support > might be Blowfish. Yes, I plan on it. Originally, I just grabbed RSAREF for a quick and dirty drop in. > Could you describe the implementation a little? Does it use the nfs > interface, or is it somewhere in the kernel file system code? Or > kernel block device code? (User-level NFS servers may involve > difficult security issues) The software is a block device driver. To use it, a user will run an executable that will pass a filespec and key to the driver. The driver then translates calls to its block interface into calls to lseek/read/write on the underlying inode. Data is d(e)ncrypted on the fly during this process. The user can then do anything you would normally do with a block device--make a file system on it, tar files to it, use it for swap. If the provided filespec is actually located remotely, and is accessed via NFS, SMB, or some other network protocol, then the benefit is that only ciphertext is passed on the wire. I'm stuck on figuring the the proper permissions for the device special file, the attachment executable, and how to deal with one user attaching the filespec to the driver, but allowing some predefined user list have access. All potential users of the driver need to have rw permission to it, but in practice, the kernel module should only honor block read/write calls make by authorized user processes. I guess I need to step back and look a what types of threat models I should address, and go from there. That, and get a good book on Unix security :) == Johnathan Corgan "For the first time in history, it is possible to jcorgan(a)aeinet.com have absolute privacy over arbitrary distances." PGP Key Fingerprint: 4F 28 69 B8 76 2E 42 3E 8B 4C 12 BB 3A 43 D4 07 -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQEVAwUBMBfKaelPfVlQ1n99AQF7+gf+I+BV1EVPQhrT7FEygT7f8PC29kZuSseU /qDlVbBrwHfzXOMgEBEkG214p9Xv1cPFQ+IlGglo321/92pxZdModA45oM3cG1ic hv8oZ+KWIL6twhKX7M3aw5tYOBTTGcdyNqEosnntE1/eAnSEPaQgt8VLyoNBjSFN 64FZvTtR7G8O2HL26SYS1PzhEl3aPRdKv3Qw+kgu1xW+VLC5DcJs34/f1Nta6xBu gFH9mfZZg4Y4VAMMyvQN+JAm7EmmIiCWAypqnwUt0SCgnpYub2EOfoKQOJ7e5hl5 9qcaLzeJsHpLGybcfT6cSEKjJ+b9MdTXrHQRPPdr2ZehcmyVSSLA7A== =G47N -----END PGP SIGNATURE-----

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Re: Full text of David Chaum's Congressional speech
by Hal 17 Dec '03

17 Dec '03

From: "Rev. Mark Grant" <mark(a)unicorn.com> > Now, I'm not sure of this, but as far as I can see, if I was a > blackmailer wanting to receive an untraceable payment I could do the > following : > > I create my ecash serial number/hash > I blind it with a random number > I send it to the payer > > Payer blinds it again and sends it to the bank > > Bank signs it and returns it > > Payer removes their blinding and returns the result to me > > I remove my blinding and send it to the bank for payment with > no chance of being traced. > > Will this work ? I believe this will work, in most blinded-ecash systems. Another way to express it is you force the user to withdraw cash such that it comes into your wallet. There are some technical counter-measures though. One is to have some secure tamper-proof hardware which enforces certain kinds of ecash transfers. The above transfer would not be a legal one. Only transfers which would allow various forms of traceability would be allowed. Another approach was described by Chaum in one of his papers. I can't remember the details, but basically the user had to go through a preliminary transaction with the bank when he opened his account, to get a whole lot of tokens which would later be turned into ecash. He has to get a lot of them because these will be for all the ecash he will use for a whole decade (or whatever). Then the withdrawal protocol is one which turns a token into an ecash value. The result of this approach is that the blinding is in effect fixed in advance and there is no way to force different blinding under duress. I posted more detail on this to the list sometime last year but I don't remember when unfortunately. Note of course that this whole traceability business only works if you have to identify yourself to the bank whenever you deposit the money. If someone allows anonymous banknote exchange then the whole "advantage" goes out the window. IMO payee anonymity will be a desired feature of ecash systems and I think Chaum is making a mistake claiming that it will not or should not exist. Another quibble is that blackmail is not a good example. The payor doesn't want to blow the whistle on his blackmailer; the blackmailer is doing the payor a favor by giving him the option of paying money rather than having the damaging information revealed. Often the payor will know who the blackmailer is. Hal

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Re: patented vs secret (was Re: RC4)
by rross＠sci.dixie.edu 17 Dec '03

17 Dec '03

>> >> By the way, since RSA is such a vocal opponent of the Clipper chip on the >> grounds of its secret Skipjack algorithm, why does it market secret >> algorithms like RC4 and RC2? Does this seen like a double face to anyone >> else? >> >> ----------------------------------------------------------- >> Russell Ross email: rross(a)sci.dixie.edu >> 1260 N 1280 W voice: (801)628-8146 >> St. George, UT 84770-4953 > >Patented does not equal secret. The argument against Clipper (at least one >of them ;-), is that it has not been subjected to review outside of the NSA. > >I believe the code for RC4 and RC2 is accessible and has been subjected to >review by many in the crypto field - you just can't use it legally without >a license. > >Noam Source code for them is available for $25,000, but only binaries are available otherwise. The source code for RC4 was leaked or reverse-engineered, so it is widely known now, but RSA has never released the algorithm officially. I have found no documentation on the algorithm behind RC2. They are in fact secret, proprietary algorithms, with the exception of the unofficial RC4 code. ----------------------------------------------------------- Russell Ross email: rross(a)sci.dixie.edu 1260 N 1280 W voice: (801)628-8146 St. George, UT 84770-4953

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Allan Schiffman on SHTTP removing PGP support
by John Gilmore 17 Dec '03

17 Dec '03

I asked Allan, who spoke on S-HTTP at a recent BayFF meeting, about this. Date: Tue, 25 Jul 95 20:02:12 PDT From: ams(a)eit.COM (Allan M Schiffman) Its true, the most recent draft of the S-HTTP spec depreciated (that is, dropped) support for PGP encapsulation. Eric and I did this because we: 1) Hadn't implemented PGP support ourselves. 2) Knew of no other S-HTTP implementation which did (we know of three other S-HTTP implementations). 3) Were unsatisfied with the formalization of PGP encapsulation format (as opposed to the behavior of a particular program). 4) Realized that our spec didn't permit implementation given our lack of support for PGP name forms and keying materials. An alternative to dropping PGP would have been to fix this, but we didn't have the time (or the motivation, given 1-3 above). That doesn't mean "X.509 all the way" for S-HTTP, by a long shot. We have publically committed (at the IETF WTS WG last week) to support MOSS, with all its name forms and keying materials. The next draft of the spec will detail how to do this, probably emphasizing the use of new key management mechanisms made possible by Secure DNS. For what its worth, I'm no fan of X.509, although I'm on record as a believer in "multiply-rooted qualified hierarchical trust" (which presumably classifies me as an "anal hierachy fan"). -Allan

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Re: Banks and Crypto
by Robert A. Rosenberg 17 Dec '03

17 Dec '03

At 13:25 7/26/95, KDAGUIO(a)aba.com wrote: >See attached file: F:\OFFILES\KODMAIL.MSG > > > >Attachment converted: Macintosh HD:KODMAIL.MSG (????/----) (0002C85B) Is there ANY reason why you did not just paste the text of this file into your message? Also, if you are going to attach files in lieu of writing messages, it might be useful to mention what Wordprocessor was used to create the file so it can be read. In this case, what format is your file in? Thank you.

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Zyxel 28.8K/ISDN modem support of DES
by sdw＠lig.net 17 Dec '03

17 Dec '03

The data sheets for the new Zyxel modems (Elite 2864/2864I) mentions that they include DES capability. The fully ISDN 2864I without/with NT-1 retails for $699/$749. Only the I model (with built-in complete ISDN) supports DES according to the data sheet. 2864 retails for $549 and they have a non-ISDN modem even cheaper. They support almost every conceivable feature, including ISDN on both B channels, ISDN on one with analog conversion on the other, and built-in microphone and speaker jacks to better support voice capability. (The 1496E's could be used as voice mail systems, etc.) Firmware in flash EPROMS (8MBit) and supports 8MByte DRAM sockets for addon memory (used to support buffering for it's plain paper fax conversion to the built-in parallel port (without computer help)). Of course, hard to tell if there's any way to control audio recording/playing while having an active data connection with the standard eprom. IF you could find out how to control it OR if there is a way to communicate in a multichannel way to the various 'peripherals', then you could produce a pretty nifty PGP-Voice system. I didn't mention lots of other features (most inherited from the 1496's): Caller-ID, distinctive ring, touch tone recognition, V.42bis over ISDN, 460.8KBPS/serial. sdw -- Stephen D. Williams 25Feb1965 VW,OH (FBI ID) sdw(a)lig.net http://www.lig.net/sdw Consultant, Vienna,VA Mar95- 703-918-1491W 43392 Wayside Cir.,Ashburn, VA 22011 OO/Unix/Comm/NN ICBM/GPS: 39 02 37N, 77 29 16W home, 38 54 04N, 77 15 56W Pres.: Concinnous Consulting,Inc.;SDW Systems;Local Internet Gateway Co.;28May95

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Re: Sat phone permit "wire"taps
by koontz＠MasPar.COM 17 Dec '03

17 Dec '03

> "Officials said government police authorities have expressed concern >that satellite telephone systems may enable people to conduct >conversations that are out of the earshot of government investigators. Perish the thought that We the People might be sovereign.

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Attachments, crypto, et al
by Donald M. Kitchen 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- My rule is no binaries, none of the time. Grepping for whitwater and foster and routing it to /dev/null seems like a good idea too.. And a great big *plonk* to our alt.conspiracy friends... Need to learn what a pointer is... Anyway, my tri-county crime spree for the next weeks will put me in San Francisco, Alameda, and Orange counties. If anyone wants to mutually sign keys, email me and I'll try to arrange something. Unfortunately my cryptoshirt won't arrive in time. I'd be able to wear it in front of LOTS of illegal aliens. So, to make up for it, I'm going to export part of the cryptosig: # Have a nice day. -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQB1AwUBMBgIxcLa+QKZS485AQFmVAMA0AijobnuJaumiM3LKfwdUK/ENRlbadJ2 DmElG3VDRaYtx4PNPXtjVXkV3CMt2CHEEvs4nmIlieZgOn/UkK0yWDbz95+qhul/ SCwOZ7jWHrika/pJKy2UX4HaEyjHtyvq =GXbe -----END PGP SIGNATURE----- <don(a)cs.byu.edu> fRee cRyPTo! jOin the hUnt or BE tHe PrEY PGP key - http://bert.cs.byu.edu/~don or PubKey servers (0x994b8f39) June 7&14, 1995: 1st amendment repealed. Death threats ALWAYS pgp signed * This user insured by the Smith, Wesson, & Zimmermann insurance company *

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Phillip Elmer Dewitt: "I screwed up"
by Vladimir Z. Nuri 17 Dec '03

17 Dec '03

there's an interesting debate going on over in alt.internet.media-coverage. Phillip Elmer Dewitt has been posting a bit on his role in the "Rimm job". Up until about now he has been very evasive, in denial, and seemingly deflecting criticism and playing "spin doctor" with his article. however, IMHO a breakthrough just happened where below he apologizes, although not for anything specific. some on the newsgroup are pressuring him to (1) run a new time story (2) issue some kind of retraction or advice to other journalists based on what he learned from the affair. I would suggest emailing him and trying to be conciliatory (don't flame his eyebrows off), but at the same time asking him to write something substantial about his experience that can either be circulated on the internet or in some other magazine. his experience in the affair, given in simple bullet-list form, would be immensely valuable to other reporters and could help "head off at the pass" (press?) many future internet-trashing articles. this is a very invaluable opportunity for cpunks to not merely whine and rant, but to try to influence the future in a positive way through your input. also in the newsgroup is an article in which he describes how 1) he had several indications the article made "suspicious" claims from people, including Mike Godwin of EFF, who he talked to on the phone about twice or so. he also noticed that it made unsupportable claims, even the one on the cover that tried to generalize the BBS info to the Internet realm. 2) he was suspicious of Rimm at a point, particularly after Rimm refused to elaborate on his background, and called his advisor and Rimm personally, and Rimm assured him that "nothing in his background would embarrass him or Time." apparently DeWitt also had heard about the "casino study". ------- Forwarded Message From: ped(a)panix.com (Philip Elmer-DeWitt) Newsgroups: alt.internet.media-coverage,alt.culture.internet,alt.culture.usenet Subject: Re: More PEDagogy (was Re: TIME Cover on Cyberporn) Date: Thu, 27 Jul 1995 19:04:56 -0500 > Yes, the damage is done. Even an honest retraction at this > point won't alter the public perception that the net is awash in > pornography. But I could honestly tell my students PED deserves > respect rather than scorn IF HE'D SWALLOW HIS PRIDE and urge his > colleagues to learn from his mistakes. > He probably won't. I'm not sure I could take my own advice > were the roles reversed. But PED, if you can't do what you should, > at least spare us any more embarrassing rationalizations. Good advice. I don't know how else to say it, so I'll just repeat what I've said before. I screwed up. The cover story was my idea, I pushed for it, and it ran pretty much the way I wrote it. It was my mistake, and my mistake alone. I do hope other reporters will learn from it. I know I have. I've also tried to explain how it happened, not to rationalize my mistakes, but to answer specific questions. I didn't want to seem unresponsive, and I generally don't mind a little embarassment. But I think you are right; answering those questions in this forum is only creating more bad will. If people are genuinely curious about how the Cyberporn debacle came to be, I will reply to queries in e-mail. - -- Philip Elmer-DeWitt ped(a)well.com TIME Magazine http://www.pathfinder.com

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cost of attacking cards (fwd)
by fc＠all.net 17 Dec '03

17 Dec '03

Forwarded message: >From fc Thu Jul 27 19:16:26 1995 Subject: cost of attacking cards To: pgf(a)tyrell.net (Phil Fraering) Date: Thu, 27 Jul 1995 19:16:26 -0400 (EDT) In-Reply-To: <199507272242.AA05163(a)tyrell.net> from "Phil Fraering" at Jul 27, 95 05:42:57 pm X-Mailer: ELM [version 2.4 PL22] Content-Type: text Content-Length: 608 > Just wondering, but do you have a cost breakdown for the > figure of $ 500.00 for a "cash card?" I published this stuf about 4 years ago and calculated $5,000, but a few months ago I spent some time with one of the top people in this field and he claimed that $500 was the right figure and backed it up with some experiments. > Would this be a single-unit manufactured-in-one-piece card > or something else? This is based on a volume business where we are breaking cards full time. -- -> See: Info-Sec Heaven at URL http://all.net Management Analytics - 216-686-0090 - PO Box 1480, Hudson, OH 44236 -- -> See: Info-Sec Heaven at URL http://all.net Management Analytics - 216-686-0090 - PO Box 1480, Hudson, OH 44236

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