Cryptography-Digest Digest #375, Volume #14 Thu, 17 May 01 21:13:01 EDT
Contents:
TC15 improvement bigtime ("Tom St Denis")
Re: taking your PC in for repair? WARNING: What will they find? (Who Dat ?)
Comparing two encrypted numbers ("Martin Schweitzer")
Re: Computing power in the world ([EMAIL PROTECTED])
Re: Comparing two encrypted numbers (David Wagner)
Re: Kernaugh maps (try #2) (thompson)
Re: Kernaugh maps (try #2) ("Paul Pires")
Re: Kernaugh maps (try #2) ("Tom St Denis")
Help working through RSA example in Applied Cryptography 2nd edition p. 468
(Beatlebum)
Re: PRNG question from newbie ("Henrick Hellstr�m")
Re: OFF-topic by now - UK crime statistics (was Re: Best, Strongest ("Trevor L.
Jackson, III")
Re: Security proof for Steak ("Henrick Hellstr�m")
Re: Questionable security measures (CIC and Cloakware!) ("Paul Pires")
----------------------------------------------------------------------------
From: "Tom St Denis" <[EMAIL PROTECTED]>
Subject: TC15 improvement bigtime
Date: Thu, 17 May 2001 22:13:19 GMT
I changed the LT (this is not on my website yet) in TC15 from the simple
cyclic thing to
a = ROTL(a, 3);
b = ROTL(b, 5);
c = ROTL(c, 11);
temp = (c*3) + (d*9);
a += temp;
b -= temp;
temp = (a*3) + (b*9);
c += temp;
d -= temp;
Where ROTL is a rotate left (cyclic).
When plugged into TC15 there are no good 1R differentials in fact the rate
of avalanche is much much higher than compared to the original LT. What's
more is that the mult and adds are nonlinear in GF(2) which makes this even
less linear.
If I reduce TC15 to eight rounds this code takes 162 cycles per block (in
x86 assembler) which is about 10 cycles per byte. If we assume about 6
sboxes are active per round (which is not likely)and that we can somehow get
by 2 rounds for free the best differential will have a prob of (2^-2)*36 =
2^-72 which is far out of reach of practical attacks. Although I doubt
there will be any attacks involving under 36 sboxes in eight rounds.
Seems neato. I the modified TC15 source is on my website but keep in mind
ITS A TOY CIPHER. I already got email requesting commercial use of TC15..
BADBAD BAD... Don't use these ciphers!
http://tomstdenis.home.dhs.org/tc15a.c
Tom
------------------------------
From: Who Dat ? <?????@?????>
Crossposted-To:
alt.privacy,alt.security.pgp,alt.security.scramdisk,alt.privacy.anon-server
Subject: Re: taking your PC in for repair? WARNING: What will they find?
Date: Thu, 17 May 2001 18:17:07 -0400
On Thu, 17 May 2001 15:40:41 -0500 "blackc1" <[EMAIL PROTECTED]> wrote:
>-----BEGIN PGP SIGNED MESSAGE-----
>Hash: SHA1
>
>"EE Support" <[EMAIL PROTECTED]> wrote in
>message news:qihM6.10096$[EMAIL PROTECTED]...
>> By now you will have witnessed the mass hysteria about Evidence
>> Eliminator.
>>
>> Evidence Eliminator is a really easy-to-use one click program which
>> is fully proven to defeat all forensic analysis software.
>>
>> It can defeat even the tools used by the US Secret Service, and the
>> USA Customs Service and LAPD.
>
>Wrong. Data can be recovered after using this product.
Where is your proof? Please provide proof that Evidence Eliminator does not
perform as advertised.
Visit our website and see for yourself that E.E. does what we claim
and a whole lot more.
http://www.evidence-eliminator.pyar.com
>-----BEGIN PGP SIGNATURE-----
>Version: PGPfreeware 6.5.8 for non-commercial use <http://www.pgp.com>
>
>iQA/AwUBOwQ3RwdsIqSi1TBNEQIZXwCguj0e57m6LvFv1J/V4i+Q1M3J8iwAoPtA
>kn03znZurLzovP0dLCo1E5sk
>=2mvq
>-----END PGP SIGNATURE-----
>
>
------------------------------
From: "Martin Schweitzer" <[EMAIL PROTECTED]>
Subject: Comparing two encrypted numbers
Date: Fri, 18 May 2001 08:24:00 +1000
Is anyone aware of a technique that allows two encrypted numbers to be
compared without decryping them? I am told that there was a paper presented
at RSA 2000 which mentions this, but I cannot find any reference to that
paper.
Thanks.
------------------------------
From: [EMAIL PROTECTED]
Subject: Re: Computing power in the world
Date: Thu, 17 May 2001 23:44:33 GMT
On Thu, 15 Mar 2001 20:09:54 GMT, AirBete<[EMAIL PROTECTED]>
wrote:
>Hi all,
>
>What is the up-to-date estimate of the total computing power in the world in
>mips-years?
>
>In 1994 (Odlyzko), it was beleive that the total computing power in the world
>was 3 x 10^8 mips-years. A safe estimate for the next 20 years was then between
>10^10 - 10^11 mips-years. This is why 10^12 mips-years was considered to be
>infeasable. But what about today and what is the forecast for the next 20 years?
>
>Thanks.
>
>AirBete.
I am coming into this late, but I noticed something in the responses,
that you seemed to miss
mips-years is mips * years
= (mip/sec) * years
= (mip/sec) * ( 31557600 sec/ 1 year) * years
= 31.557.600 * mip
= 3.1557600 * 10^13 instructions
------------------------------
From: [EMAIL PROTECTED] (David Wagner)
Subject: Re: Comparing two encrypted numbers
Date: 17 May 2001 23:50:35 GMT
Martin Schweitzer wrote:
>Is anyone aware of a technique that allows two encrypted numbers to be
>compared without decryping them?
What kind of encryption? (Randomized or not? Public-key or not?)
Do you want an interactive protocol, or a non-interactive proof?
If the former, who is trusted and who isn't? What's the setting?
In general, the answer is yes, but we'll need more information about
what you're looking for to answer your question in more detail.
------------------------------
Subject: Re: Kernaugh maps (try #2)
From: [EMAIL PROTECTED] (thompson)
Date: Fri, 18 May 2001 00:35:46 GMT
"Tom St Denis" <[EMAIL PROTECTED]> wrote in
news:rwXM6.120696$[EMAIL PROTECTED]:
>
> "Jeffrey Walton" <[EMAIL PROTECTED]> wrote in message
> news:3b043aff$0$[EMAIL PROTECTED]...
>> : So the Kernaugh map is just a way to
>> : optimize the expressions for where a 1 occurs in the table?
>>
>> I find it easier and less error prone than reducing by hand. As jlcooke
>> stated, it can be bone with min terms (0s) also.
>>
>> Also, this method only works for 4 inputs (possibly 6 if you can do this
>> with a cube - that would be impressive, but not impossible).
>>
>> If you eventually want to reduce larger equations (for example, 8
>> inputs), use the Quine-McClusky method. This method has the added
>> benefit of being programmable. Its a little more difficult to work by
>> hand.
>
> I've seen a couple of sites about QM but they don't really explain what
> happens... they mainly say "I start with xyz and end with abc"..
>
> Any beginner info you can share?
>
> Thanks,
> Tom
>
>
I have a C program that takes up to 12 inputs (easily expanded if need be)
that performs the Quine-McCluskey method. I found it on the web years ago.
A header comment indicates that it was written in '81.
It uses a command line interface, and you enter the table a line at a time.
However, the table can be in a .txt file that you can pipe into the
program, in DOS/Unix fashion (e.g., QM <my_table.txt >my_output.txt).
I don't have a web site to post it. I could zip it up (.c, .exe, and .txt
example files) and post it here -- but this is NOT a binary ng. I don't
give out my email address on ng's anymore, due to too much spam. Any
suggestions for posting this or requests for it please post here and I'll
check back in a day or so.
Unfortunately, the code does not explain the theory of operation.
Cheers
------------------------------
From: "Paul Pires" <[EMAIL PROTECTED]>
Subject: Re: Kernaugh maps (try #2)
Date: Thu, 17 May 2001 17:43:47 -0700
I would be very interested in obtaining a copy.
Please Email a copy to me if you can.
[EMAIL PROTECTED]
I dont worry about spammers, their about the only
ones who respond to my posts :-)
Thank you.
Paul
thompson <[EMAIL PROTECTED]> wrote in message
news:C7_M6.15596$[EMAIL PROTECTED]...
> "Tom St Denis" <[EMAIL PROTECTED]> wrote in
> news:rwXM6.120696$[EMAIL PROTECTED]:
>
> >
> > "Jeffrey Walton" <[EMAIL PROTECTED]> wrote in message
> > news:3b043aff$0$[EMAIL PROTECTED]...
> >> : So the Kernaugh map is just a way to
> >> : optimize the expressions for where a 1 occurs in the table?
> >>
> >> I find it easier and less error prone than reducing by hand. As jlcooke
> >> stated, it can be bone with min terms (0s) also.
> >>
> >> Also, this method only works for 4 inputs (possibly 6 if you can do this
> >> with a cube - that would be impressive, but not impossible).
> >>
> >> If you eventually want to reduce larger equations (for example, 8
> >> inputs), use the Quine-McClusky method. This method has the added
> >> benefit of being programmable. Its a little more difficult to work by
> >> hand.
> >
> > I've seen a couple of sites about QM but they don't really explain what
> > happens... they mainly say "I start with xyz and end with abc"..
> >
> > Any beginner info you can share?
> >
> > Thanks,
> > Tom
> >
> >
>
>
>
> I have a C program that takes up to 12 inputs (easily expanded if need be)
> that performs the Quine-McCluskey method. I found it on the web years ago.
> A header comment indicates that it was written in '81.
>
> It uses a command line interface, and you enter the table a line at a time.
> However, the table can be in a .txt file that you can pipe into the
> program, in DOS/Unix fashion (e.g., QM <my_table.txt >my_output.txt).
>
> I don't have a web site to post it. I could zip it up (.c, .exe, and .txt
> example files) and post it here -- but this is NOT a binary ng. I don't
> give out my email address on ng's anymore, due to too much spam. Any
> suggestions for posting this or requests for it please post here and I'll
> check back in a day or so.
>
> Unfortunately, the code does not explain the theory of operation.
>
> Cheers
------------------------------
From: "Tom St Denis" <[EMAIL PROTECTED]>
Subject: Re: Kernaugh maps (try #2)
Date: Fri, 18 May 2001 00:47:26 GMT
"thompson" <[EMAIL PROTECTED]> wrote in message
news:C7_M6.15596$[EMAIL PROTECTED]...
> "Tom St Denis" <[EMAIL PROTECTED]> wrote in
> news:rwXM6.120696$[EMAIL PROTECTED]:
>
> >
> > "Jeffrey Walton" <[EMAIL PROTECTED]> wrote in message
> > news:3b043aff$0$[EMAIL PROTECTED]...
> >> : So the Kernaugh map is just a way to
> >> : optimize the expressions for where a 1 occurs in the table?
> >>
> >> I find it easier and less error prone than reducing by hand. As
jlcooke
> >> stated, it can be bone with min terms (0s) also.
> >>
> >> Also, this method only works for 4 inputs (possibly 6 if you can do
this
> >> with a cube - that would be impressive, but not impossible).
> >>
> >> If you eventually want to reduce larger equations (for example, 8
> >> inputs), use the Quine-McClusky method. This method has the added
> >> benefit of being programmable. Its a little more difficult to work by
> >> hand.
> >
> > I've seen a couple of sites about QM but they don't really explain what
> > happens... they mainly say "I start with xyz and end with abc"..
> >
> > Any beginner info you can share?
> >
> > Thanks,
> > Tom
> >
> >
>
>
>
> I have a C program that takes up to 12 inputs (easily expanded if need be)
> that performs the Quine-McCluskey method. I found it on the web years ago.
> A header comment indicates that it was written in '81.
>
> It uses a command line interface, and you enter the table a line at a
time.
> However, the table can be in a .txt file that you can pipe into the
> program, in DOS/Unix fashion (e.g., QM <my_table.txt >my_output.txt).
>
> I don't have a web site to post it. I could zip it up (.c, .exe, and .txt
> example files) and post it here -- but this is NOT a binary ng. I don't
> give out my email address on ng's anymore, due to too much spam. Any
> suggestions for posting this or requests for it please post here and I'll
> check back in a day or so.
>
> Unfortunately, the code does not explain the theory of operation.
This would be neat to toy with. You can publicly ftp it to 24.112.8.23,
port number 2121, u/p = scicrypt/scicrypt.
All are welcomed to ftp there and back.
Tom
------------------------------
From: [EMAIL PROTECTED] (Beatlebum)
Subject: Help working through RSA example in Applied Cryptography 2nd edition p. 468
Date: Fri, 18 May 2001 00:54:02 GMT
I'm stumped by the line that reads:
d = 79^-1 mod 3220 = 1019
Obviously I'm reading the notation wrong, but 79^-1 is 0.0126...,
how the heck does 1019 come out of this?
TIA
Beatle.
------------------------------
From: "Henrick Hellstr�m" <[EMAIL PROTECTED]>
Subject: Re: PRNG question from newbie
Date: Fri, 18 May 2001 02:50:54 +0200
I have put together a specification of Steak as a pdf, modified the cipher
slightly according to some kind suggestions, and wrote down an
assembler-free implementation. Furthermore I boldly raised some outraging
security claims, hoping to wake someone up. ;-)
The links to the Steak2 documents can be found at
http://www.streamsec.com/steak.asp at the bottom of the page.
Could you (Paul Pires) please send me your specification of the "Bleaming
Strock cipher" as a pdf?
--
Henrick Hellstr�m [EMAIL PROTECTED]
StreamSec HB http://www.streamsec.com
"Paul Pires" <[EMAIL PROTECTED]> skrev i meddelandet
news:36EM6.130800$[EMAIL PROTECTED]...
>
> Henrick Hellstr�m <[EMAIL PROTECTED]> wrote in message
news:9duvhs$dur$[EMAIL PROTECTED]...
> > "Paul Pires" <[EMAIL PROTECTED]> skrev i meddelandet
> > news:HgBM6.32288$[EMAIL PROTECTED]...
> > > I'll make you a deal. I'll look at yours and comment if you'll
> > > do the same with mine :-)
> >
> >
> > Sure. Where can I find it?
>
> Well, the brief description is right here in Sci.crypt.
>
> Re: Comments appreciated. (Was, Bleaming Strock cipher)
>
> I have a more comprehensive description in PDF
> form I could send if you find it of interest. I looked
> at your web reference. Do you have a PDF or text
> version? I prefer to do my reading on the porch.
> I'm old fasioned, reading off a screen just doesn't
> work best for me.
> >
> >
> > --
> > Henrick Hellstr�m [EMAIL PROTECTED]
> > StreamSec HB http://www.streamsec.com
> >
> >
>
>
>
------------------------------
From: "Trevor L. Jackson, III" <[EMAIL PROTECTED]>
Subject: Re: OFF-topic by now - UK crime statistics (was Re: Best, Strongest
Date: Fri, 18 May 2001 00:54:16 GMT
"Douglas A. Gwyn" wrote:
> "Trevor L. Jackson, III" wrote:
> > And in the U.S. B&E, while a violent crime, does not rise to the level
> > of a threat of death or great bodily harm. The only actions that
> > justify a potentially lethal response are rape, arson, a lethal threat
> > and their respective attempts.
>
> That's not quite right, and the details are jurisdiction-dependent.
Hardly.
>
> In most US jurisdictions, one may lawfully use deadly force to stop
> what a reasonable person would perceive to be an immediate threat
> of death or grave bodily harm to self or others to whom one is
> commonly considered to owe protection (family, guests).
In fact, that protection extends to any innocent. And rape and arson are
considered exactly such a threat.
> In some
> US jurisdictions uninvited intruders (trespassers) in one's home
> are assumed de facto to present sufficient threat to permit use of
> deadly force.
No. The criteria are ability, opportunity, and jeopardy, and all three must
be present in order to justify the use of lethal force. There is no US
jurisdiction in which mere presence satisfies those criteria.
I suspect you may have replaced "threat" with "use". The presence of an
intruder certainly justifies the threat of deadly force, but does not even
begin to justify the use of deadly force.
> However, once they are fleeing the scene, the law
> considers the immediate threat to have passed. For specific
> information on the theoretical rules *and* their practical
> implementation in your own jurisdiction, it is best to consult a
> local specialist in such laws. In the basic handgun training
> I underwent many years ago, this topic was an important part of
> the course.
It is probably the most important aspect, answering the question of "when"
rather than "how".
------------------------------
From: "Henrick Hellstr�m" <[EMAIL PROTECTED]>
Subject: Re: Security proof for Steak
Date: Fri, 18 May 2001 02:58:46 +0200
I have put together a specification of Steak as a pdf, modified the cipher
slightly according to your kind suggestions, and wrote down an
assembler-free implementation. The links to the Steak2 documents can be
found at
http://www.streamsec.com/steak.asp at the bottom of the page.
--
Henrick Hellstr�m [EMAIL PROTECTED]
StreamSec HB http://www.streamsec.com
"Benjamin Goldberg" <[EMAIL PROTECTED]> skrev i meddelandet
news:[EMAIL PROTECTED]...
> Henrick Hellstr�m wrote:
> >
> > "Benjamin Goldberg" <[EMAIL PROTECTED]> skrev i meddelandet
> > news:[EMAIL PROTECTED]...
> > > Henrick Hellstr�m wrote:
> > > >
> > > > Have a look at http://www.streamsec.com/sattacks.asp
> > > >
> > > > It might be considered to be a draft so far. I would appreciate
> > > > any
> > > > comments.
> > >
> > > I didn't look at the security proof, but did glance at the source
> > > code.
> > >
> > > My comments:
> [snip]
> > > Wtf are those big huge tables?
> >
> > They are described on the page http://www.streamsec.com/mt.asp. I
> > probably ought to insert a link from the reference source code to that
> > page.
> >
> > The table in the source code is the expansion of a 32x32 linear bit
> > matrix, so that only four lookups will be needed for each 32 bit input
> > (one for each byte of the input). The design rationale for choosing
> > that particular matrix is purely empirical, but it might be re-created
> > in a few steps:
> > a) Start with the 4x4 MDS matrix of TwoFish.
> > b) Apply a quadruple of s-boxes so that the matrix degenerates into a
> > 32x32 invertible bit matrix over GF(2).
> > c) Transpose the rows and then the columns of the 32x32 matrix
> > according to a pair of constant permutations.
>
> How much code would it take to do this? How does that compare to the
> size of writing the tables into your source directly?
>
> You've explained it only partially. You haven't said what those four
> sboxes are, and you haven't said what the permutations are.
>
> > > How the bleep do I know that they
> > > aren't some sort of back door?
> >
> > You don't. It is impossible to prove that there is no backdoor. But a
> > partial justification would be the fact that Steak uses random single
> > cycle s-boxes, and as far as my imagination goes it is impossible that
> > any back door into the linear matrix would be there for any internal
> > key data and any vector size. Basically, what I am saying is that
> > there might be (small) sets of weak keys, but not really any back
> > door.
>
> Is there a distinguisher for these weak keys?
>
> --
> Shift to the left, shift to the right, mask in, mask out, BYTE, BYTE,
> BYTE !!!
------------------------------
From: "Paul Pires" <[EMAIL PROTECTED]>
Subject: Re: Questionable security measures (CIC and Cloakware!)
Date: Thu, 17 May 2001 17:55:09 -0700
Tom St Denis <[EMAIL PROTECTED]> wrote in message
news:CWXM6.120842$[EMAIL PROTECTED]...
>
> "Mok-Kong Shen" <[EMAIL PROTECTED]> wrote in message
> news:[EMAIL PROTECTED]...
> >
> >
> > Tom St Denis wrote:
> > >
> > > Cloakware just released a product that uses CIC's signature detection
> > > algorithms but they won't release the details (I know since I work for
> > > Cloakware).
> > >
> > > This is a shameful crypto-practice and both companies should be a shame
> of
> > > themselves.
> > >
> > > Reminds me of the RSA SecurID "scandal". It is secure because ... umm
> ...
> > > we say so!
> >
> > You said above that you are working for that firm? So
> > you are presumably under some sort of non-disclosure
> > agreement? (I simply wonder that you could scold your
> > employer publically without endangering your contract.)
>
> Technically I am like an intern at the company. I wasn't working on the
> Signature stuff but when I asked if I could try analyzing it they told me
> "We are under a NDA from CIC .. so no...".
>
> I don't really blame Cloakware but I wish they would say "CIC if you want us
> to use this we will go public".
>
> My main function there is R&D so I would figure getting "info" would be part
> of it... hmm..
>
> So far what I have said to this usenet is not under my NDA... so that's no
> prob...
>
> I wish more people would speak up when their company does silly things.
There weren't any gray crayons in your box when you were growing up,
where there?
Courage and conviction rarely conflict with discretion if you put a little
thought into it. This boss might be disposable but the next one may have
already formed an opinion on you. You can't fight the good fight if you
aren't playing the game. Don't get tossed out too soon. "Fair" or "right"
doesn't matter when you shoot off your own foot. Of course, if you think
that's the way it should be done, go for it big! swipe their source and
post it!, NOT.
You are far more competent than that.
Paul
>
> Tom
>
>
------------------------------
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