Cryptography-Digest Digest #150, Volume #10 Tue, 31 Aug 99 18:13:03 EDT
Contents:
Re: Which of these books are better ? (Doug Stell)
Re: HIV testing (Medical Electronics Lab)
Re: What if RSA / factoring really breaks? (DJohn37050)
Re: Can we have randomness in the physical world of "Cause and Effect" ? (John
Savard)
Re: Pincodes ([EMAIL PROTECTED])
Re: Pincodes (John Savard)
Re: WinZip 7.0 (David Hamer)
Re: n-ary Huffman Template Algorithm (Mok-Kong Shen)
Re: original source code for robert morris crypt.c circa 1970's (Keith A Monahan)
Re: 512 bit number factored (Paul Koning)
Re: What if RSA / factoring really breaks? ("David J Whalen-Robinson")
Re: On employing message-decoys (Mok-Kong Shen)
Re: 512 bit number factored (Paul Koning)
Implementing crypto algorithms in Fortran. ("Steven Alexander")
Re: 512 bit number factored ([EMAIL PROTECTED])
Re: Implementing crypto algorithms in Fortran. ("Tony T. Warnock")
Re: Cryptography Items and Issues (Ian Goldberg)
Unpatented Public/private key system ("Micha�l Chass�")
Re: Unpatented Public/private key system (SCOTT19U.ZIP_GUY)
Re: Implementing crypto algorithms in Fortran. (SCOTT19U.ZIP_GUY)
Re: 512 bit number factored (Paul Crowley)
Ciphertext disguised as plaintext? (newbie question) (Matt Gibson)
----------------------------------------------------------------------------
From: [EMAIL PROTECTED] (Doug Stell)
Subject: Re: Which of these books are better ?
Date: Tue, 31 Aug 1999 15:09:38 GMT
On Tue, 31 Aug 1999 04:23:24 GMT, "JaeYong Kim" <[EMAIL PROTECTED]>
wrote:
>for both conceptional understanding and mathematical understanding..
>1. Applied Cryptography, Bruce Schneier
>2. Handbook of Applied cryptography, Menezes et al
>3. Cryptography: Theory and Practice, Stinson
The books are very different and largely complementary. So it is hard
to answer your question.
1. Applied Cryptography, Bruce Schneier:
I think of this as the Cryptographer's Desk Reference. It has a little
of everything and points you to where you can get more detail. It is
probably the best book for the beginner to start with and a good
reference for everyone else.
2. Handbook of Applied cryptography, Menezes et al:
This is a much more comprehensive text on a narrower set of topics,
most notably the math. Menezes and van Stone are outstanding math
professors. It is fairly easy reading, although not as easy as
Schneier's book.
3. Cryptography: Theory and Practice, Stinson:
This is a fairly heavy textbook.
------------------------------
From: Medical Electronics Lab <[EMAIL PROTECTED]>
Subject: Re: HIV testing
Date: Tue, 31 Aug 1999 11:39:22 -0500
Doug Goncz wrote:
> There is no newsgroup to discuss social implications of cryptographic
> technology, as far as I know.
Repost it to talk.politics.crypto. You'll get
more responses :-)
Patience, persistence, truth,
Dr. mike
------------------------------
From: [EMAIL PROTECTED] (DJohn37050)
Subject: Re: What if RSA / factoring really breaks?
Date: 31 Aug 1999 15:26:57 GMT
Triple DES.
Don Johnson
------------------------------
From: [EMAIL PROTECTED] (John Savard)
Crossposted-To: sci.physics
Subject: Re: Can we have randomness in the physical world of "Cause and Effect" ?
Date: Tue, 31 Aug 1999 16:51:26 GMT
Dave Knapp <[EMAIL PROTECTED]> wrote, in part:
>Quantum mechanics requires either true randomness or nonlocality.
While, as someone has pointed out, many worlds can substitute for
randomness, I don't see how either one substitutes for nonlocality -
required by the EPR experiment.
However, I do *have* a substitute for nonlocality; faster-than-light
phenomena, so far internal to quantum systems. But that is still a
separate and additional requirement in addition to randomness, as I
understand it.
John Savard ( teneerf<- )
http://www.ecn.ab.ca/~jsavard/crypto.htm
------------------------------
From: [EMAIL PROTECTED]
Subject: Re: Pincodes
Date: Tue, 31 Aug 1999 17:23:14 GMT
In article <WDSy3.134$[EMAIL PROTECTED]>,
"JuDa$" <[EMAIL PROTECTED]> wrote:
>
> Hello !
>
> I need help to break pincodes, can somebody help me please ?
>
What do you mean by pincodes?
Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't.
------------------------------
From: [EMAIL PROTECTED] (John Savard)
Subject: Re: Pincodes
Date: Tue, 31 Aug 1999 17:52:46 GMT
"JuDa$" <[EMAIL PROTECTED]> wrote, in part:
>I need help to break pincodes, can somebody help me please ?
a) Why do you think that anyone would want to help you steal money
from people's bank accounts, and
b) what makes you think there is a code to break: surely it would be
safer to store a hash of the PIN number at a central site than on the
magnetic stripe of the card.
Of course, if the bank absolutely insists on letting people withdraw
some small sum of money when the lines are down, they could still
protect against hackers as follows:
1) Record only a hash of the PIN on the card, not the PIN itself.
2) Encrypt that hash - with one of a thousand or more keys, stored on
a hard disk at each bank machine - with an indication of which key to
use placed on the card.
That ought to protect against a dictionary-search attack.
John Savard ( teneerf<- )
http://www.ecn.ab.ca/~jsavard/crypto.htm
------------------------------
Date: Tue, 31 Aug 1999 08:34:09 -0400
From: David Hamer <[EMAIL PROTECTED]>
Subject: Re: WinZip 7.0
Thank you...
DHH
"[ Dr. Jeff ]" wrote:
> In article <[EMAIL PROTECTED]>,
> David Hamer <[EMAIL PROTECTED]> wrote:
> >Can anyone point me towards a password-recovery utility - freeware
> >or shareware - for WinZip v7.0 ??
>
> Http://www.elcomsoft.com/azpr.html It's well worth the price
> asked. You're welcome.
------------------------------
From: Mok-Kong Shen <[EMAIL PROTECTED]>
Crossposted-To: sci.image.processing,sci.math,alt.comp.compression
Subject: Re: n-ary Huffman Template Algorithm
Date: Tue, 31 Aug 1999 20:33:42 +0200
Alex Vinokur wrote:
>
> Mok-Kong Shen <[EMAIL PROTECTED]> wrote:
> > A question just for my understanding: How can frequencies be
> > non-numerical at all? If you have a number of frequencies and have
> > only their ordering according to magnitude but not know their
> > numerical values, how can you expect to obtain a coding that is
> > optimal?
> > So from Huffman algorithm point of view
> > it is not important what type of cost is.
> > The algorithm is using only operator< and operator+.
This only reflects the fact that a Huffman tree can correspond to a
wide range of frequency distributions, i.e. that a Huffman tree does
not uniquely defines the frequencies of the nodes. But a non-numerical
data type 'by definition' can't support the operator + (excepting that
+ is often employed to represent string concatenation, so A + B becomes
aabb, if A is the string 'aa' and B is the string 'bb'). Could you show
(with a concrete real-life example) an instance of a 'non-numerical
cost', i.e. the 'value' of a variable of that type and the result of
applying your operator + on two such 'values' so that one may better
comprehend the semantics of that operator?
M. K. Shen
------------------------------
From: [EMAIL PROTECTED] (Keith A Monahan)
Subject: Re: original source code for robert morris crypt.c circa 1970's
Date: 31 Aug 1999 12:57:29 GMT
Robert Morris, was that the father of Robert "Tap-in" Morris, the guy
who wrote the internet worm back in '88 ?
Same guy?
Keith
dan braun ([EMAIL PROTECTED]) wrote:
: Does anybody have a copy of the original (circa 1970?) source code for
: robert h. morris' crypt.c?
: thanks in advance
: dan
: --
: Dan Braun - Broadcast Engineer
: Toronto, Ontario, Canada
: [EMAIL PROTECTED], [EMAIL PROTECTED]
------------------------------
From: Paul Koning <[EMAIL PROTECTED]>
Subject: Re: 512 bit number factored
Date: Tue, 31 Aug 1999 14:17:21 -0400
DJohn37050 wrote:
>
> The counter to using the largest key possible is performance and
> interoperability. Some constrained devices can only use smaller keys with
> acceptable performance. Security is fine as long as it does not impede what
> one wants to do! And if someone else can only handle smaller keys, then I must
> also to talk to them. So a goal is to find a key that is large enough to not
> attack and small enough for good performance.
No, I'd say the right algorithm is to choose a key that's comfortably
large enough and scrap any hardware too wimpy to support it. In this
day
of 0.15 um ASIC geometries there is no excuse for devices that can't
support
at least a 1k bit key.
paul
------------------------------
From: "David J Whalen-Robinson" <[EMAIL PROTECTED]>
Subject: Re: What if RSA / factoring really breaks?
Date: Tue, 31 Aug 1999 14:28:57 -0400
JPeschel <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> David J Whalen-Robinson <[EMAIL PROTECTED]>writes, in part:
>
> >Nobody is ready for that, but there are other algorithms to move to.
> >(DES would still be secure, and there are public key alternatives not
> >reliant on
> >factoring.)
> But DES is already insecure.
It's true that 56 bits is a small key space.
I just mean that it wouldn't get any easier if the factoring problem was
solved.
(at least as far as I know )
It would still be as secure as it is now, which, as you suggest, may not be
that much!
I mentioned the DES family of encryption because I believe that it's
commonly used
in goverment systems, and people would still have to take the time to crack
those keys.
I'm not recommending that anybody move to DES.
>
> Joe
>
>
> __________________________________________
>
> Joe Peschel
> D.O.E. SysWorks
> http://members.aol.com/jpeschel/index.htm
> __________________________________________
>
------------------------------
From: Mok-Kong Shen <[EMAIL PROTECTED]>
Subject: Re: On employing message-decoys
Date: Tue, 31 Aug 1999 20:30:45 +0200
Sundial Services wrote:
>
> -- then the best approach is probably to use an algorithm that, you are
> as certain as you can be, cannot be broken within the 24 hour lifespan
> of the data.
It is (implicitly) assumed that the communicaton partners have employed
the best algoritms available to them under the financial, technical,
legal (Wassenaar Arrangement, etc.) or other prevailing controlling
conditions and that the analyst cannot or cannot afford to utilize
additional resources beyond what is estimated by Alice.
M. K. Shen
------------------------------
From: Paul Koning <[EMAIL PROTECTED]>
Subject: Re: 512 bit number factored
Date: Tue, 31 Aug 1999 14:11:16 -0400
"Douglas A. Gwyn" wrote:
>
> Note that factoring a 512-bit number is in itself not interesting;
> I can do that myself for certain numbers. What would be interesting
> would be the development of a method that can rapidly factor *any*
> 512-bit number, e.g. the product of randomly-selected primes having
> widths around 250 bits. (If the method is any good, it could be
> used in the process of selecting primes, to verify their primeness.)
> One hopes that that is what was reported. (My Dutch isn't good
> enough to read the original article.)
It says that they factored the RSA-155 challenge. One would assume
that used randomly picked primes, or at least definitely not
"easy" primes.
paul
--
!-----------------------------------------------------------------------
! Paul Koning, NI1D, D-20853
! Xedia Corporation, 50 Nagog Park, Acton, MA 01720, USA
! phone: +1 978 263 0060 ext 115, fax: +1 978 263 8386
! email: [EMAIL PROTECTED]
! Pgp: 27 81 A9 73 A6 0B B3 BE 18 A3 BF DD 1A 59 51 75
!-----------------------------------------------------------------------
! "The only purpose for which power can be rightfully exercised over
! any member of a civilized community, against his will, is to prevent
! harm to others. His own good, either physical or moral, is not
! a sufficient warrant." -- John Stuart Mill, "On Liberty" 1859
------------------------------
From: "Steven Alexander" <[EMAIL PROTECTED]>
Subject: Implementing crypto algorithms in Fortran.
Date: Tue, 31 Aug 1999 12:30:30 -0700
As a project for a Fortran programming class, I would like to build a
utility that can encrypt files using one of 2-3 different algorithms. I
would like to use DES as one of them not for its security value(56bits is
too damn short) but because it seems to be a good learning tool for
cryptographers and cryptanalysts alike. Anyway, it does not seem that
Fortran natively supports unsigned integers which will completely botch my
implementations. If anyone has any information on using unsigned integers
in Fortran or implementing any cryptosystem in Fortran I would greatly
appreciate their help. I'm not asking for anyone to write my homework, I
just want to know how it can be done. Thanks in advance.
-steven alexander
[EMAIL PROTECTED]
------------------------------
From: [EMAIL PROTECTED]
Subject: Re: 512 bit number factored
Date: 30 Aug 1999 14:11:38 -0400
In article <[EMAIL PROTECTED]>, "Douglas A. Gwyn" <[EMAIL PROTECTED]> writes:
>Note that factoring a 512-bit number is in itself not interesting;
>I can do that myself for certain numbers. What would be interesting
>would be the development of a method that can rapidly factor *any*
>512-bit number, e.g. the product of randomly-selected primes having
>widths around 250 bits. (If the method is any good, it could be
If you accept 4 days on c. 3000 pc's followed by 2 weeks on
a Cray C90, as "rapidly factor" then that's what we've demonstrated.
The 256-bit primes were randomly selected at/by RSA shortly after
RSA129 was factored. The method is the number field sieve.
B. Dodson
------------------------------
From: "Tony T. Warnock" <[EMAIL PROTECTED]>
Subject: Re: Implementing crypto algorithms in Fortran.
Date: Tue, 31 Aug 1999 14:18:39 -0600
Reply-To: [EMAIL PROTECTED]
Steven,
Although Fortran does not support unsigned integers, this should be no problem
in implementing either DES or other algorithms. The main tools you will need
are the Fortran shift and boolean operators. These operate (bitwise) on
integers so the sign bit does not matter, it's just another bit. RSA would be
more of a problem, not so much because of the signs but because
multi-precision integers are difficult to program.
DES ought to run quite well. I've implemented similar algorithms (in Fortran
of course) with no problems. IDEA uses only 16-bit arithmetic so it would run
well in a 32-bit environment.
Tony
> As a project for a Fortran programming class, I would like to build a
> utility that can encrypt files using one of 2-3 different algorithms. I
> would like to use DES as one of them not for its security value(56bits is
> too damn short) but because it seems to be a good learning tool for
> cryptographers and cryptanalysts alike. Anyway, it does not seem that
> Fortran natively supports unsigned integers which will completely botch my
> implementations. If anyone has any information on using unsigned integers
> in Fortran or implementing any cryptosystem in Fortran I would greatly
> appreciate their help. I'm not asking for anyone to write my homework, I
> just want to know how it can be done. Thanks in advance.
>
------------------------------
From: [EMAIL PROTECTED] (Ian Goldberg)
Subject: Re: Cryptography Items and Issues
Date: 31 Aug 1999 20:47:42 GMT
In article <[EMAIL PROTECTED]>,
Stefek Zaba <[EMAIL PROTECTED]> wrote:
>In sci.crypt, JPeschel ([EMAIL PROTECTED]) wrote:
>
>> Though it's been a quite a while, I seem to remember this sort of "backdoor"
>> as fairly common, no matter what the crypto algorithm. Wasn't the techique
>
> [ of fixing all but 40 bits of a blockcipher key ]
>
>> once
>> used by Netscape in the international versions of its browser?
>
>Not in any sinister way: it was, and continues to be, the documented way in
>which RC5 is weakened for export (prior to www.fortify.net 'ing :-) in
>Netscape browsers; that is, for simplicity of coding, the key fed into the
>RC5 implementation is 128 bits in length whether the "export" or "domestic"
>mode is being used; but the "export" flavour has 88 of the 128 bits fixed.
>
>At least, that's what my memory tells me I heard/read from usually reliable
>sources was the case.
Almost. It's RC4, not RC5, and it works like this:
Pick a random 128-bit value. (If you're a furriner, send 88 bits of it
in the clear.) Hash the value through MD5. Use that result as the RC4 key.
Note the distinction between using a fixed value for the 88 bits and just
publishing the bits you randomly choose. The former allows for a dictionary
attack; the latetr doesn't.
- Ian
------------------------------
From: "Micha�l Chass�" <[EMAIL PROTECTED]>
Subject: Unpatented Public/private key system
Date: Tue, 31 Aug 1999 16:08:51 -0400
Hi,
I'd like to know some Public/Private key system that aren't patented
(that I can use on the public domain) and, if possible, references to have
informations about them.
Also, does someone has a suggestion of unpatented strong encryption
algorithm possible to use with Visial Basic 5.0
Thank's
Micha�l Chass�
Qu�bec, Canada
------------------------------
From: [EMAIL PROTECTED] (SCOTT19U.ZIP_GUY)
Subject: Re: Unpatented Public/private key system
Date: Tue, 31 Aug 1999 22:09:37 GMT
In article <kEWy3.75$[EMAIL PROTECTED]>, "Micha�l Chass�"
<[EMAIL PROTECTED]> wrote:
>Hi,
>
> I'd like to know some Public/Private key system that aren't patented
>(that I can use on the public domain) and, if possible, references to have
>informations about them.
>
> Also, does someone has a suggestion of unpatented strong encryption
>algorithm possible to use with Visial Basic 5.0
>
>
>
You can attempt to use by program in Visual Basic But since Basic is usually
very very bad at doing things fast it may take for every to run. Check out
scott19u at my site. You have my persmission to attempt such a mission if
you choose to. But I can't really belive one would write seriuos encryption in
such a slow language.
David A. Scott
--
SCOTT19U.ZIP NOW AVAILABLE WORLD WIDE
http://www.jim.com/jamesd/Kong/scott19u.zip
http://members.xoom.com/ecil/index.htm
NOTE EMAIL address is for SPAMERS
------------------------------
From: [EMAIL PROTECTED] (SCOTT19U.ZIP_GUY)
Subject: Re: Implementing crypto algorithms in Fortran.
Date: Tue, 31 Aug 1999 22:04:25 GMT
In article <7qhd77$[EMAIL PROTECTED]>, [EMAIL PROTECTED] (Paul Rubin) wrote:
>In article <S5Wy3.9525$[EMAIL PROTECTED]>,
>Steven Alexander <[EMAIL PROTECTED]> wrote:
>>As a project for a Fortran programming class, I would like to build a
>>utility that can encrypt files using one of 2-3 different algorithms. I
>>would like to use DES as one of them not for its security value(56bits is
>>too damn short) but because it seems to be a good learning tool for
>>cryptographers and cryptanalysts alike. Anyway, it does not seem that
>>Fortran natively supports unsigned integers which will completely botch my
>>implementations. If anyone has any information on using unsigned integers
>>in Fortran or implementing any cryptosystem in Fortran I would greatly
>>appreciate their help. I'm not asking for anyone to write my homework, I
>>just want to know how it can be done. Thanks in advance.
>
Actually I have used Fortran for over 30 years and fortran is a very
easy langage to do the programing you want. The use of unsigned integers
or signed integers is only as a convience to the porgramer. IF the machine
your on uses 2's complimnet arithmetic then you can use signed numbers
as unsigned. The only porblem usually occure in the mind of the porgramer
during the actaul writting of the number out or the entering of the number in
to the porgram. But fortran on most machines in most implimentions handles
the numbers perfectly. Example lets say your intergers are I*2 wich is 16
bits the number 3 is 3 if you think about it as signed or unsigned. But the
number -2 can be thought of as 65534. You might have problems with arrays if
you use the whole number as an index but you can even handle that if you use
your brain a little.
>There is a Fortran implementation of DES in the first (but not the
>second) edition of "Numerical Recipes", by Press, Teukolsky et al.
>
David A. Scott
--
SCOTT19U.ZIP NOW AVAILABLE WORLD WIDE
http://www.jim.com/jamesd/Kong/scott19u.zip
http://members.xoom.com/ecil/index.htm
NOTE EMAIL address is for SPAMERS
------------------------------
From: Paul Crowley <[EMAIL PROTECTED]>
Subject: Re: 512 bit number factored
Date: 31 Aug 1999 21:49:53 +0100
Bob Silverman <[EMAIL PROTECTED]> writes:
> Secondly, as Ron himself has admitted, when he made the
> claim about '40 quadrillion years' for RSA-129, he had forgotten
> about the continued fraction algorithm. (invented in 1970). Ron
> had only considered trial division when he made this now
> famous and mistaken estimate. Even back in 1977 it would
> not have taken anywhere close to what Ron had estimated.
> (But it was legitimately out of reach then)
The telling of this one I remember was that Ron was thinking of the
Pollard rho technique, which had been developed recently, but that he
had not considered more effective techniques that were already known.
But I could be mistaken.
--
__
\/ o\ [EMAIL PROTECTED] Got a Linux strategy? \ /
/\__/ Paul Crowley http://www.hedonism.demon.co.uk/paul/ /~\
------------------------------
From: [EMAIL PROTECTED] (Matt Gibson)
Subject: Ciphertext disguised as plaintext? (newbie question)
Date: Tue, 31 Aug 1999 22:06:21 +0100
(Apologies if this is an FAQ; I did read search the FAQ and Deja, but
perhaps I was using the wrong terminology.)
Are there any automatic encryption systems which produce a ciphertext
which appears, at least to a casual glance, to be a plaintext? Is there
a word for a system like this?
Thanks,
Matt
--
"It's the gaps between the rain that count,
and learning how to live amongst them"
-- Jeff Noon, _Pixel Juice_
Matt Gibson http://www.gothick.dial.pipex.com
------------------------------
** FOR YOUR REFERENCE **
The service address, to which questions about the list itself and requests
to be added to or deleted from it should be directed, is:
Internet: [EMAIL PROTECTED]
You can send mail to the entire list (and sci.crypt) via:
Internet: [EMAIL PROTECTED]
End of Cryptography-Digest Digest
******************************
