- cypherpunks-legacy - lists.cpunks.org

scheme
by Mike Johnson 26 Feb '93

26 Feb '93

> This encryption scheme uses XOR to encrypt data 1 character > at a time. Because of this it is suitable for protocols > where you need to send single bytes (or less) at a time. > Examples of this would be interactive ascii. Also it > is easily applicable to crippled lines like 7 bit lines. > This is because if the plaintext is 7 bits you can send > just the 7 bits after the XOR. Even more general you can > use it to encrypt any size at a time, down to single bits > if you just have 1 bit to send immediately and dont want > to wait for more data to become applicable. > Ok. So what are its disavantages? Syncronization, as > soon as synchronization is gone thats it, its all over. Each > block of 'pad' is generated from previous plaintext, if you > cant figure out the previous plaintext you are lost. > > Notice it uses a hash() function, this could be anything, ie > DES, or perhaps a one way function (no unhash() is ever needed). > The algorithm is fairly simple, the beginning is a bit wierd > and could have been done several ways. The first 8 bits in > this implementation are used for synchronization. > ...(source code omitted) If you use DES, you are just using a variation of DES in cipher block chaining mode. If you use some other hash function, your cipher is as weak as the hash function. If you use key bytes directly to XOR with, and never reuse key material, you have a variation of the one time pad (which is good, but takes LOTS of key material). If you reuse key material when XORing it directly, you have a weak cipher vulnerable to a known plain text attack. There is nothing really new here... For more info on this, if you have a PC and a modem, you can call a BBS at 303-938-9654, download CRYPTMPJ.ZIP, and read THESIS.DOC in that file. Perhaps one of you could put this file at an ftp site for wider distribution? The stuff in that file about data compression is kind of out of date, but the cryptographic information (including some source code) might be of interest to some others in this group. Mike Johnson mikej(a)exabyte.com

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Dining Crypto -- An Introduction
by Duncan/Lois Frissell 26 Feb '93

26 Feb '93

(Timothy May) Thanks for your repost of your message from the "Dawn of Time" (August 1992). Your list of "What DC Nets are Good For" was not specific enough for my taste. What DC Nets (untraceable communications) are good for: 1) Once voice/video/VR makes it to the nets and once we have enough bandwidth/speed even realtime communications can be untraceable: It's December 2000 and President Elect Clinton (Hilary) calls me for advice. The call goes to my "Virtual Communications Server" located "Somewhere on the Nets". The packets are forwarded to me after being split up and sent their various ways through anonymous remailers. My half of the conversation travels back the same way. The packets pay the anonymous remailers for their services with digital cash attached to their address headers. We notice no time lag because the nets are fast and the packets carry a "realtime" priority. With the proper setup, the President of the US will be talking to me without knowing (or being able to find out) where (or who) I am. 2) This means markets freed from even the theoretical possibility of regulation. Anything that can be digitized can be sold with no restraints save the absence of a willing buyer. Books, movies, VR epics, financial products, and all non-physical services can be traded without coercion (and without taxation). Remember too that "non-physical services" includes almost all management and professional services. The technique of "anonymous credentials" can be used to check out those you deal with. 3) The lack of regulation in the "spiritual realm" will distort market transactions in the still controlled "physical realm." People will tend to "unbundle" the non-physical aspects of their services and sell them on the nets even if it is less convenient to do so because of the *tax* savings. 4) The reduction is government "revenue" as economic activity transfers to the nets will induce a beneficial downward spiral in the authority and power of government. 5) People who become used to freedom in one part of their lives (their work and play on the nets) will not enjoy the coercion they suffer in the remainder of their lives (the place they sleep). They will have the motivation and the tools to liberate their whole lives. All without the Libertarian Party converting a single person. Freedom is a powerful recruiter. Duncan Frissell

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No Subject
by trump＠pluto.ee.cua.edu 26 Feb '93

26 Feb '93

things on my mind well i am relatively new to the cypherpunks list so i have a few comments to make on my behalf. (1) i read in a message about the current rise in the member of subscribers and this rise was passively related to Mondo. There was also some concern expressed in this message about the number of people dropping the list and from those comments i reply that the list does generate an awful lot of mail. And this mail is often quite technical (well if i was talking from a technically illiterate point of view it would very technical... i generally can follow the idea and their technicality though) and this technicality is a turn off to the Mondo type. I know that Mondo has said allot about the problems of personal security on the information age but not in tech-speek... i believe that most of the Mondo types will unsubscribe from this list because it is not a part of their focal of interest. Yes the list talks about current issues but again from a technical point of view and for the Mondo crowed n general it is a real turn off. (2) Att Mail is nice. If anyone cares i will find out about what features it has... i.e. ftp, telnet, irc, etc... My sister is an Att employee and she is given an attmail.com address for her on the go and work sight mail... it is nice because i can stay in contact with her because Att mail has a 800 international dialup. My sister has a portable NCR computer with modem and can get my mail where ever she is. In 1992 she was back and forth from Puerto Rico and New Jersey for AT&T now she is all over Europe. A very nice convenience for the (wo)man on the run. (3) Am I from D.C. and i am unsure if the world knows about this but in November the Secret Service raided our 26oo meeting at the Pentagon City mall. I know that we here in D.C. have all the more concern about security and frequently use are PGP keys because there is little doubt that our BBS are being taped et cetera and i am certain that in the near future there will be an upsurge of us D.C. boyz to your list. (4) About DES. The data encryption standard is, no doubt in my mind, quite cracked by NSA. If it is not completely cracked it is at least very easy to get into by these boys. I have found that there is too much evidence that NSA has gotten in to DES pretty well. For starters (not a proof by the way) the cryptographers who work for NSA spend most of their time breaking encryption and its pretty mind boggling to think that no short cuts have been found to DES by a bunch of dedicated cyptographers. Damn if that was my job and my field of knowledge i am sure i would have at least a little short cut of some sort. So i have been doing a little work on DES but i am unsure about the validity of my ideas and their effects on encryption... if i do feel that i find something i will certainly let it out but i was just wondering if people had any DES source in all or any languages??? it would be very helpful to get cross language DES source... Well i hope that this note wasn't too boring but i felt that i had to get it out to the list. so hopefully i will get some

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Overload! Unsubscribe with regrets
by Vince Tessier 26 Feb '93

26 Feb '93

I regret that I do not have time to keep up with the volume of mail this list generates, and must unsubscribe. If, however, you are able to digestify all the mail into a single piece, I would be interested again. -- Vince -- Vince Tessier (vtessier(a)vela.acs.oakland.edu) "When guns are outlawed, only Carl Rowan will have guns."

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Re: Law&Disorder (fwd)
by mbrennan＠netcom.com 26 Feb '93

26 Feb '93

Everything is happening in the Bay Area. And I'm stuck down here in the L.A. wasteland (sigh). Oh well. At least there's mailing lists. ----------------------------------------------------------------------------- Michael Brennan Internet: mbrennan(a)netcom.com Compuserve: 76206,2462 Applelink: M.BRENNAN

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Re: Poor Man's Anonymous Remailer
by George A. Gleason 26 Feb '93

26 Feb '93

Duncan's posting about AT&T mail as a "poor man's anonymous mailbox" misses one crucial fact. The moment you dial an 800 number, you generate a record of your phone number via ANI, which means AT&T gets that information in realtime and can probably correlate it with your phone account and service address and name. If you want anonymity, never ever ever use any service which requires you call in via an 800 number. -gg(a)well.sf.ca.us

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Re: Finding Mac PGP software?
by mbrennan＠netcom.com 25 Feb '93

25 Feb '93

Dave Banisar <banisar(a)washofc.cpsr.org> writes: > MacPGP is available at mac.archives.umich.edu via gopher and FTP. Dave, I've tried ftp'ing to that site, but I get "unknown site". Is that really the correct address? I appreciate the info. ----------------------------------------------------------------------------- Michael Brennan Internet: mbrennan(a)netcom.com Compuserve: 76206,2462 Applelink: M.BRENNAN

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Job Available
by dnorris＠ibeam.intel.com 25 Feb '93

25 Feb '93

Intel (Mobile Software Architecture and Technology group) is seeking a person to be responsible for all security issues related to mobile computers. Applicant should have a BS/MS Degree in Computer Science, and more than 2 years experience in software architecture. Experience in MSDOS and/or Windows development environment is required. Experience with software, network and/or portable computer security is desired. Authentication and Encryption experience is required. Experience with challenge/response devices and Defender(TM) type devices is desired. This individual will be a senior level individual contributor that will be responsible for all aspects of security in a laptop/palmtop environment. Problems must be identified and solutions advocated within Intel and to outside vendors. Prototypes and Proof-of-Concept software must be developed. Partial responsibilities include: Work with Corporate Business Development to recommend investment in outside security companies. Evaluate security products from outside vendors. Present portable security vision at trade shows and conferences. Be an Intel expert on security. Work with Corporate Information Services to incorporate new security products within Intel. The position is available in Hillsboro Oregon (a suburb of Portland). For more information please contact either Nancy Ohlson (503) 696-2572 or David Norris dnorris(a)ibeam.intel.com Please do not post responses to cypherpunks.

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Unsubscribe me
by Christo Delaroderie 25 Feb '93

25 Feb '93

Please unscribe me. ctd

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Re: Anonymous flooding
by tcmay＠netcom.com 25 Feb '93

25 Feb '93

Johan Helsingius <julf(a)penet.FI> writes: >> Ultimately, I think this is the only way that anonymous remailers will >> be able to function. Otherwise, the public outcry the first time one of >> these remailers are abused will cause these full remailers to be >> shutdown, or otherwise cut off from the net. > >Exactly as has happened to anon.penet.fi. ;-) > > Julf Have I missed something? Has anon.penet.fi been shut down or cut off from the net? Please fill us in. I think most of us are rooting for you and your system (though some *.army.mil readers are probably not--they just can't stand the thought of defense secrets being sold on crypto anarchy nets!). -Tim -- 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: 2^756839 | Public Key: MailSafe and PGP available.

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