December 2003 - cypherpunks-legacy

MATH: Brands cash, Hal's posts
by Karl Lui Barrus 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Cypherpunks, or maybe that's Atompunks, Earlier, Hal posted several excellent messages concerning Brands' cash, and some introductory material. I always find it useful to work through various protocols by hand (well, with Mathematica), working with real numbers to help understand the protocol and how it works. So like I did a long time ago when Hal posted a description of Chaumian cash, I will give an example of the protocols described. I intend to follow along Hal's posts and work math as it comes up (and try to keep the notation consistent!). I'll not be using numbers large enough to give actual security. For folks with Mathematica, the functions of interest are PowerMod[a,b,c] to calculate a^b mod c, and Mod[a,b] to calculate a mod b. Hal's first post was introductory material on discrete logs: * Generators > Discrete-log based cryptosystems generally work with a modulus n which is > prime, along with a "generator" g < n such that the series g^0, g^1, g^2, > ... , includes all values from 1 to n-1. It is pretty straightforward to > find such n's and g's. It is easy to compute g^x for any x, but > intractable to calculate x given just g^x. Finding a generator g is easy if you know the factorization of n-1. You just need to calculate g^((n-1)/q) mod n for all values of q, the prime factors of n. If any of the results are 1, then g is not a generator. So say you want to see if 5 is a generator mod 2047. The prime factors of n - 1 = 2046 are { 2, 3, 11, 31 }, so you calculate: 5 ^ (2046/2) mod 2047 = 1034 5 ^ (2046/3) mod 2047 = 622 5 ^ (2046/11) mod 2047 = 1435 5 ^ (2046/31) mod 2047 = 622 None of these turned out to equal 1, so 5 is a generator mod 2047. * Diffie-Hellman key exchange > 1. Alice chooses a random x and sends GX = g^x to Bob. Bob chooses a > random y and sends GY = g^y to Alice. Let's use g = 10, and pick p = 17389. 10 is indeed a generator mod 17389. Alice chooses x = 53, and calculates g^x mod p = 10^53 mod 17389 = 9059 Bob chooses y = 4321 and calculates g^y mod p = 10^4321 mod 17389 = 16077 They exchange, so Alice receives GY = 16077 and Bob receives GX = 9059 > 2. Alice calculates GY^x, which is g^(y*x). Bob calculates GX^y, which > is g^(x*y). Alice calculates 16077^53 mod 17389 = 11643 Bob calculates 9059^4321 mod 17389 = 11643 > 3. These are equal, so they use them as their shared secret value. Alice and Bob agree to the shared secret 11643. > An observer sees only GX and GY, and without knowledge of x and y is > unable to calculate g^(x*y). * DH-based identification protocol For this example, suppose we use g = 10, p = 17389 as above. Also, Paul chooses x = 555 to be his private key, therefore 10^555 mod 17389 = 11106 is his public key. > 1. Vicki chooses a random y and sends GY = g^y to Paul. Vicki randomly chooses y = 1994, so she sends 10^1994 mod 17389 = 13848. > 2. Paul calculates GYX = GY^x = g^(y*x) and sends that back to Vicki. Paul calculates 13848^555 mod 17389 = 8324, and sends it back. > 3. Vicki confirms that GYX = GX^y; both should be g^(x*y). Vicki checks 11106^1994 mod 17389 = 8324. This matches what Paul sent back. * Schnorr identification protocol > 1. Paul chooses a random w and sends GW = g^w to Vicki. Paul chooses w = 200, and sends 10^200 mod 17389 = 14097 to Vicki. > 2. Vicki chooses a random c and sends it to Paul. Vicki chooses c = 561 and sends this to Paul. > 3. Paul calculates r = cx+w and sends that to Vicki. Paul calculates r = 561 * 555 + 200 = 311555. > 4. Vicki confirms that g^r = (GX^c)*GW. Both should be g^(cx+w). Vicki checks: 10^315555 mod 17389 = 4594 (11106^561) 14097 mod 17389 = ((11106^561 mod 17389) * 14097) mod 17389 = 4594 * Chaum discrete log interactive signature protocol Here, we'll pick m = 1040. Thus, Paul can calculate MX = 1040^555 mod 17389 = 8608 > 1. Paul chooses a random w and sends GW = g^w and MW = m^w to Vicki. As above, Paul chooses w = 200, so he sends GW = 14097 and MW = m^w mod p = 1040^200 mod 17389 = 472 to Vicki. > 2. Vicki chooses a random c and sends it to Paul. She chooses 561 again. > 3. Paul calculates r = cx+w and sends that to Vicki. He calculates 311555 again. > 4. Vicki confirms that g^r = (GX^c)*GW. Both should be g^(cx+w). She > also confirms that m^r = (MX^c)*MW. Both should be m^(cx+w). Vicki checks g^r as above. Now she also checks: m^r mod p = 1040^311555 mod 17389 = 13723 (MX^c)*MW = (8608^561)*472 mod 17389 = 13723 * Chaum discrete log signature protocol Well, this is similar to the above protocol except a hash function is used. I'll do something similar for Hal's other posts as time permits. Karl Barrus klbarrus(a)owlnet.rice.edu -----BEGIN PGP SIGNATURE----- Version: 2.6 iQCVAgUBLl5uPsSF/V8IjI8hAQE4/AP/VNauuo2nIWvF7xukbh6zNXK/pTnD7vGM 7jQeD9Hk7z9a/GXD2OTjlKUf1HAtFRkPB95X3HS/u5TzO1RdUIoxuiUok38At8vX UUBaRXaF6JJUI8xkvgOt9qCrSnZNKhjh4wZ2JxxOUY/0rB/1TBRzPe/MIIzyy0Ee bKaCRv+gJLA= =esaf -----END PGP SIGNATURE-----

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Spoofing Weapons 2
by John Young 17 Dec '03

17 Dec '03

Forwarding mail by: misra(a)gardener.lanl.gov ("Raymond H. Misra") on Fri, 26 Aug 10:28 AM ------------------- On Aug 26, 2:11am, MEINKING(a)delphi.com wrote: > Subject: > > Each message pounds another nail into my silent coffin. Inside it is dirty, > dank and pathetic. I have received every post. I have read every post, and > each time, I have had what seems like everything to say. But I don't say > it. > > Yet I do know where I want to go, where I want to reach. I want to reach > those that have pounded the nails into my coffin, that have participated in > luring me into the apeiron, trapping me in the coffin, and discarding me > forever. > > To them I can only say this: > > "The fire is burning me. It is erupting from the inside, from the > pit of my gut and bursting forth. The flames it releases want > victims to claim for their own giddy disgust and restoration is no > longer possible." > > >From the depths of the apeiron, at a distance deeper than hell itself a > bright light expands devouring each bit of darkness in its wake. If you > listen, you can hear it speak the sound - the sound of creation. >-- End of excerpt from MEINKING(a)delphi.com You wouldn't be desribing the weapons discussion on "cypherpunks" list for the past few days, would you? -- Raymond H. Misra

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Re: DSPs
by jdd＠aiki.demon.co.uk 17 Dec '03

17 Dec '03

In message <199408262009.NAA17046(a)unix.ka9q.ampr.org> Phil Karn writes: > > Yes, but even scalar multiplication is so much faster on a DSP than on > most general purpose CPUs that it seems like a definite win. The 486 > takes from 13-42 clock cycles to perform a multiply, depending on the > operand sizes and number of significant bits in the multiplier. The Motorola DSP96002 does an integer multiply in 2 or 3 clocks, so a 33 MHz device does 11 million multiplies (and moves) a second. The chip costs about $50. The newer TI C40 does a 32-bit integer multipy in 1 clock, so a 50 MHz device can output 200 MB/s of results. It can read in a single clock cycle but writes take two cycles (sometimes more). So although it can theoretically read 200 MB/s, it can only write 100 MB/s. However, it has six serial links, each one of which has a 20 MB/s bandwidth, so in theory it can pump out 100+120 = 220 MB/s. However, in practice you would expect the chip to be I/O bound. It costs something like $200 a chip. The real advantage of the C40 is that C40s can be connected together using their serial links. This allows them to be arranged in interesting 3D topologies. In this respect the C40 is intended to be an upgrade on the transputer, which has only four links, and tends to die when connected into large 2D meshes, because the transputers spend too much of their time passing messages. If C40s are connected in pipelines, with three links used as input from the preceding stage and three links used to drive the next stage, you can run them comfortably at 60MB/s. You might choose to do three multiplies on each 32-bit operand at this rate, giving you effectively multiplications at 45 MHz at each stage of the pipeline. > Even > if you couldn't keep the pipeline full on a chip like the PowerPC, you'd > still be well ahead. Ahead of the 486 maybe, but the C40 makes the PowerPC a dog. > But then I hear people say that it's not the multiplication that slows > down modular exponentiation, it's the modular reduction. Can you elaborate? -- Jim Dixon

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FCC Regulation (fwd)
by Al Billings 17 Dec '03

17 Dec '03

---------- Forwarded message ---------- Date: Thu, 25 Aug 94 18:20:01 CDT From: Dave Hurst <hurst(a)vistatech.com> To: nexus-gaia(a)netcom.com, fringeware(a)illuminati.io.com, leri(a)pyramid.com Subject: FCC Regulation (fwd) Forwarded from the com-priv mailing list: (UPI) WASHINGTON, DC. The White House confirmed today that the FCC will become the Federal agency to assume responsibility for regulating the so-called "Information Super Highway." Today this consists of an autonomous network of computers known collectively as the Internet. Usually reliable sources revealed that the government is becoming increasingly apprehensive about the Internet's uncontrolled growth and the potential for damage to national security. A highly placed government source was quoted as saying "...now anyone with a thousand dollars can obtain the computer hardware and software necessary to communicate on the Internet. Irresponsible individuals can easily transmit messages worldwide. Clearly, there is a need for government regulation." In response to these concerns the FCC is rumored to be preparing restrictive regulations to assure "responsible use" of the Internet. The FCC is reportedly cooperating with other national and international agencies to coordinate these regulations. Several former eastern bloc countries and Italy are reportedly coordinating their internal regulation planning with the FCC. Although details are sketchy at this time, these new regulations are likely to take the form of some sort of license examination for Internet users. Despite the fact that a costly new government bureaucracy will be established, it will likely save money in the long run, according to government sources. "A single USENET posting may cost hundreds if not thousands of dollars, therefore, if licensing reduces such postings by only 10% the savings will more than recover these additional costs", said a highly placed government source. Expert government watchers have been able to piece together a fairly comprehensive picture of the soon-to-be-proposed license requirements. Based upon the past history of the FCC, the test will likely consist of three parts: theory, jurisprudence and practice. The theory portion of the examination will include written examination of the principles of digital logic, elements of generic machine language programming, and comprehensive knowledge of TCP/IP and network interfacing hardware. The jurisprudence portion will assess the candidate's basic knowledge of the regulations governing use of the Internet and will cover ethical as well as legal issues. Licensing will likely include an "Internet oath" requirement in which the candidate will swear to uphold certain basic standards of conduct. Users of the Internet will be required to broadcast their license numbers at logon and intermittently after connection to the Internet. The practice portion of the examination is likely to be the most controversial. Reportedly, all candidates must pass a typing skills examination and achieve no less than 40 words per minute to obtain a (temporary) novice license. This must be raised to 80 words per minute before a regular-status license will be issued. Novices will restricted to operating networked computers having speeds of less than 5 Mhz or operation of SLIP or dial-up connections of no greater than 2400 baud. (It is rumored that the FCC will make 5 Mhz replacement crystals available at a nominal charge to temporarily slow computers of novice operators). The FCC also recognizes that there are conditions when terminal emulators are not available. Therefore, an expert class will be established for communication using only numeric keypads and bi-digit numeric displays. Although needing a minimum of equipment, this mode will require sending, receiving and manual translation of raw ASCII codes. Guidelines for minimum communication rates for this mode have yet to be established while the FCC awaits public input. Although felt to be a desirable goal for all users, this class of license will only be required by individuals operating wireless (RF) LANS. Asked what the effect of proposed regulations would have on the Internet, a highly placed official noted that these rules "should not be considered prohibitive, as they simply bring regulation of the Internet in line with other communication modes under FCC governance." However, the source did feel that such regulations should be very helpful in restraining the rapid growth of the Internet.

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Re: (Fwd) Something of Interest
by Blanc 17 Dec '03

17 Dec '03

From: jf_avon |I received this out of the blues. I suppose that you received it |too. ........................................................... I didn't receive it, and I set off quite a round of discussion with Jim & the list, at one point. Guess I'm not considered controversial enough to get it. :>) .. Blanc

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Anon Remailers
by dwomack＠runner.utsa.edu 17 Dec '03

17 Dec '03

Some time back, Xenon maintained a list of anonymous remailers, along with what records were kept, i.e., simple counter, to & from addresses, full text for some time period, etc. I know the list is available via finger (Many compliments to those involved in that!!!), but was wondering if the record- keeping aspect was reported anywhere? And no, I've never written to whitehouse.gov, don't intend to, and wouldn't on a bet!!! Regards, Dave

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Crime Bill
by Jim choate 17 Dec '03

17 Dec '03

Does anyone know if the death penalty has been extended to weapons or arms trafficking? If so this means that simply sending a disk w/ pgp on it now rates a lethal injection.... Anywhere I can get the full text? It does not appear to be up on the white house or other gov. sources yet. Thanks.

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Re: PGP fanatacism
by nobody＠ds1.wu-wien.ac.at 17 Dec '03

17 Dec '03

Earlier, Tim May wrote: > Not only do many of us not do all this stuff (have you seen Eric > Hughes signing his messages? How about John Gilmore?), but some people > have decided to stop reading e-mail altogether. Donald Knuth, for > example. A wise man. > I'm happy that you PGP fans are thoroughly infatuated with using PGP > for everything. Just knock off the clucking and sighing about those > who don't see it as the end-all and be-all of today's communications. > It reeks of fanaticism. Interesting. I wonder what this says though... cypherpunks promote encryption, digital cash, dc nets, data havens... but wouldn't ever be caught actually using any of the above. Hell, that stuff is way too plebian. I'd rather advocate it that actually be in the uncomfortable position of following my own advice.

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Re: PGP fanatacism (Cost-benefit analysis)
by blancw＠pylon.com 17 Dec '03

17 Dec '03

Responding to msg by nobody(a)ds1.wu-wien.ac.at Interesting. I wonder what this says though... cypherpunks promote encryption, digital cash, dc nets, data havens... but wouldn't ever be caught actually using any of the above. .................................................. I think this says is that it is important to apply the appropriate tools when it is apropos and the situation calls for it, but not when there isn't sufficient cause to warrant the time & trouble. Blanc

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Crypto Panel at Rocky Mtn. Inet User's Group
by Richard Johnson 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Just a short announcement culled from the minutes of the last RMIUG meeting. It's of greatest interest to those of us in CO. I suppose the panelists on the list already know about it (but one can never be completely sure). || The next RMIUG meeting is scheduled for Tuesday, September 13th. || We will have a "Crypto-Fest" panel discussion organized by RMIUG || member Duane Thompson (ak351(a)freenet.hsc.colorado.edu) || including Phil DuBois, lawyer for Phil Zimmerman, author of the || encryption program Pretty Good Privacy (PGP), Mike Johnson, || encryption expert, engineer, software programmer, inventor of || the Diamond encryption algorith, and Phil Zimmerman himself, || speaking to us about encryption technology, the benefits and || uses of recent versions of PGP, and issues surrounding || encryption technology. The RMIUG meetings are held at the NCAR mesa facility in Boulder, CO at 7pm on the 2nd Tuesday of the month. To get there, find Table Mesa (yeah, stupid name) or South Boulder Road, and head West on it 'till you reach the end and find the building Woody Allen rapelled out of in Sleeper. The auditorium is just inside the main entrance. Show up at 6:30 for schmoozing. Rich -----BEGIN PGP SIGNATURE----- Version: 2.6 iQCVAgUBLl8EMfobez3wRbTBAQE26gP9GAjrnb/dxCP3XBKtZipjWtFE18AM7C0V t/e45SwqDXRBsn4r/5O4MEuEJUbQ0dmgBK1VvXHgwP+suPf+KbKYHi6ASFG02Ecw Mo9ZiFSUE1KHwwoiK28GrLMRBAYP5lOAKV2jyLckDfeSRmb+4fTgQB7baHH4qa7k emyKs+hlH+I= =8Rk8 -----END PGP SIGNATURE-----

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