Cryptography-Digest Digest #528, Volume #10 Mon, 8 Nov 99 20:13:05 EST
Contents:
Re: How protect HDisk against Customs when entering Great Britain (Anonymous)
Re: Proposal: Inexpensive Method of "True Random Data" Generation ("Douglas A. Gwyn")
Re: What sort of noise should encrypted stuff look like? ("Douglas A. Gwyn")
Re: Re: How protect HDisk against Customs when entering Great Britain (CoyoteRed)
Re: Re: How protect HDisk against Customs when entering Great Britain (CoyoteRed)
Re: Doesn't Bruce Schneier practice what he preaches? (Bruce Schneier)
Re: Doesn't Bruce Schneier practice what he preaches? (Bruce Schneier)
Re: Q: Removal of bias (Mok-Kong Shen)
Re: Scientific Progress and the NSA (was: Bruce Schneier's Crypto Comments...)
(Bruce Schneier)
Re: Signals From Intelligent Space Aliens? Forget About It. (John Kennedy)
Re: Doesn't Bruce Schneier practice what he preaches? (John Kennedy)
which international version ("Nicholas Cole")
Encryption Placement (Benjamin Valenti)
Re: Incompatible algorithms ([EMAIL PROTECTED])
----------------------------------------------------------------------------
Date: 8 Nov 1999 21:39:33 -0000
From: Anonymous <Use-Author-Address-Header@[127.1]>
Subject: Re: How protect HDisk against Customs when entering Great Britain
Crossposted-To:
alt.security.pgp,comp.security.pgp.discuss,comp.security.pgp.tech,alt.privacy,alt.privacy.anon-server
Bruno Wolff III <[EMAIL PROTECTED]> wrote:
: You lack imagination. Better would be to reprogram the floppy to start
: damaging other peoples systems after about 10 scans. After that story gets
: out no one is going to trust them to boot their system off their floppies.
There is already a well-known name for this technology. It's called "virus".
------------------------------
Crossposted-To: sci.math,sci.misc,sci.physics
From: "Douglas A. Gwyn" <[EMAIL PROTECTED]>
Subject: Re: Proposal: Inexpensive Method of "True Random Data" Generation
Date: Mon, 8 Nov 1999 20:37:42 GMT
"Steven B. Harris" wrote:
> No kidding?
Not only "no kidding", but the original hex-digit-only algorithm
has been augmented by further work and now we can produce any
arbitrary decimal digit of pi. It shouldn't take long to locate
more info via a Web search.
------------------------------
From: "Douglas A. Gwyn" <[EMAIL PROTECTED]>
Subject: Re: What sort of noise should encrypted stuff look like?
Date: Mon, 8 Nov 1999 20:43:27 GMT
wtshaw wrote:
> Given a *good* spectrum in ciphertext, you can skew it to make a
> misleading one of your own picking.
It would cost you bandwidth. Why bother?
------------------------------
From: [EMAIL PROTECTED] (CoyoteRed)
Subject: Re: Re: How protect HDisk against Customs when entering Great Britain
Date: Mon, 08 Nov 1999 21:43:46 GMT
Reply-To: this news group unless otherwise instructed!
On Mon, 08 Nov 1999 11:04:11 -0500, "Trevor Jackson, III"
<[EMAIL PROTECTED]> wrote:
>CoyoteRed wrote:
>
>> We deserve privacy only when it's nobodies' business but our own.
>
>I think you have the presumption inverted. We deserve privacy in all areas
>except where there is an overriding public interest, narrowly construed.
>
No, I think I have it right.
If /it's/ no one else's business, then I can keep it to myself or tell
the world. When /it's/ no one else's business then they have no claim
on it and therefore no control. But as soon as /it/ becomes some one
else's business, then it is no longer private.
The problem is when does /it/ become some one else's business. Child
abuse and molestation, rape, murder, assault, battery, etc.; the list
goes on. This is when your privacy ends.
If you are doing something that does not harm, or take advantage of,
anyone else, then /it/ is no one else's business.
>Also, we only "deserve" privacy if we are willing to defend it.
Also, we "deserve" privacy at all times, up to the point where we
interfere with someone else's rights. Then are right's must be
balanced against the other's.
But, maybe we'll just to agree to disagree...
--
CoyoteRed
CoyoteRed <at> bigfoot <dot> com
http://go.to/CoyoteRed
PGP key ID: 0xA60C12D1 at ldap://certserver.pgp.com
------------------------------
From: [EMAIL PROTECTED] (CoyoteRed)
Subject: Re: Re: How protect HDisk against Customs when entering Great Britain
Date: Mon, 08 Nov 1999 21:43:51 GMT
Reply-To: this news group unless otherwise instructed!
On 08 Nov 1999 11:44:43 -0500, Stephen Carpenter
<[EMAIL PROTECTED]> wrote:
>[EMAIL PROTECTED] (Coyote-Red) writes:
>
>
>> If there wasn't any demand...
>
>Thats a big if...there will ALWAYS be demand.
True... But a large demand needs to be answered with a large supply
and we both know where that leads.
>
>Some people have fantasies about having sex with children. In fact
>I doubt you will find those fantasies to be uncommon. Its considered
>"perverse" in our society (in other societies throughout time it was
>perfectly acceptable and common), that "perversion" alone is enough to
>entice people.
It also depends on your definition of kiddie porn. When Dr. Laura
talks about how perverse it is for some guy to look at a budding 13
years old, I get very mad. Does this mean that I was some kind of a
deviant when I was 12, 13, 14 years old?! I know I sure did look back
then! Was that wrong? No, I don't think so. But what is wrong is
for grown men using girls to make money for them; be it by force,
manipulation, or other wise. We have rules about when citizens become
emancipated for a reason.
>The simple fact is, that id someone sits in his own home, or on his laptop
>and looks at a picture of anything, he is harming noone.
He, himself, may not be doing harm, but he is part of the market and
the market, on a whole, is what comprises the demand and ,ultimately,
the harm.
>However, taking away everyones privacy solves nothing.
I'm not saying taking away /everyone's/ privacy. Just that you can't
have total privacy supplant someone else's right to be free from harm.
>
>Its the drug war all over again. A few people decide something is morally
>wrong, and decide that everyone is going to have to conduct their personal
>private life by these moral rules.
Well, actually, morality is determined by the majority. They majority
will do what they /think/ is right and how it looks to others. If
people didn't care about how others may view them because of what they
believe in, then the world would be a very different place.
>> Same with most of the other vises, except this is against defenseless
>> individuals and that's where I draw the line.
>
>And your right to draw the line but...
>veiwing a picture does nothing. When the picture is taken, th damage is
>already done. Go after the people taking the pictures..
Agreed! However, after the one picture is viewed what comes next is
the problem. If more pictures are viewed we will sooner or later run
out. If we want more, then MORE DAMAGE NEEDS TO BE DONE!
>
>Besides...the only way to catch them, is to invade on EVERYONES privacy
>across the board. If you ask me, thats tantamount to saying "Everyone is
>guilty until proven innocent" or "Its better to jail a hundred innocent men
>then to let a single guilty men go free"
I don't think so. The internet can be looked at as our streets and
our PCs are our homes. The police patrol the streets, but don't come
into our homes. Now, when a police officer sees something suspicious
then he may investigate further; surveillance, wire tapping, etc.
until he builds a case against the suspect. Then with probable cause,
and the proper authority, he can enter your home. This can be the
same way with the internet. No need to invade people's PCs (homes)
until there is probable cause. Monitor the traffic. People seem to
like to talk about privacy on the internet and say nothing about
people being able to plainly view the visitors to their homes.
I'm a very private person, this one of the reasons that I use a 'nym.
No one /needs/ to know who I am. But also I'm a father and a father's
responsiblilty is to protect his children from, and to educate them
about, the dangers out there.
--
CoyoteRed
CoyoteRed <at> bigfoot <dot> com
http://go.to/CoyoteRed
PGP key ID: 0xA60C12D1 at ldap://certserver.pgp.com
------------------------------
From: [EMAIL PROTECTED] (Bruce Schneier)
Subject: Re: Doesn't Bruce Schneier practice what he preaches?
Date: Mon, 08 Nov 1999 21:48:38 GMT
On Sun, 31 Oct 1999 22:18:34 -0500, "Adam Durana" <[EMAIL PROTECTED]>
wrote:
>Hi,
>
>I think you guys are missing the real point Schneier was trying to get
>across. He was not saying give out the source code to your software, he was
>saying that the encryption methods used in your software should be public.
>You have to trust that the designers and coders of the software correctly
>implemented it. Thats a lot of trust to put in someone, but you can test
>the software to make sure it is correctly implemented in most cases. (Test
>vectors?) There is a great deal of software that uses secret methods and
>there is no way to tell if it is secure, until someone breaks it or reverse
>engineers it. What Schneier was saying is that the encryption methods used
>in software should be public, because the strength of a method should rest
>in itself, not in its obsurcity.
Again, I have been away and I don't have accesss to the beginning of
this thread. I don't know about what I said when, but I do believe
that open source software (with public source code) has a better
chance of being secure than closed source software. So the person who
chided me for not releasing the source code to PasswordSafe had an
excellent point.
Bruce
**********************************************************************
Bruce Schneier, Counterpane Internet Security, Inc. Phone: 612-823-1098
101 E Minnehaha Parkway, Minneapolis, MN 55419 Fax: 612-823-1590
Free crypto newsletter. See: http://www.counterpane.com
------------------------------
From: [EMAIL PROTECTED] (Bruce Schneier)
Subject: Re: Doesn't Bruce Schneier practice what he preaches?
Date: Mon, 08 Nov 1999 21:49:29 GMT
On Mon, 01 Nov 1999 07:39:14 -0500, John Kennedy
<[EMAIL PROTECTED]> wrote:
>>If that's all Schneier meant, then he's wrong. Just knowing the algorithms
>>used is not enough. You have to know that they were put together correctly,
>>for example, that any random number generators used were not chilled, that
>>any keys created were not chosen with malice, that no key bits were being
>>leaked somehow.
This is all true.
>>Schneier knows all this. That's why I suspect you're misinterpretting him.
I agree. I was probably misinterpreted. Wouldn't be the first time.
>Just so. The only thing I can figure is that he doesn't really
>consider Password Safe a security tool. But it is positioned as one
>and the use of Blowfish would strongly imply that it is one.
It is. And I will release source code for the next version.
Bruce
**********************************************************************
Bruce Schneier, Counterpane Internet Security, Inc. Phone: 612-823-1098
101 E Minnehaha Parkway, Minneapolis, MN 55419 Fax: 612-823-1590
Free crypto newsletter. See: http://www.counterpane.com
------------------------------
From: Mok-Kong Shen <[EMAIL PROTECTED]>
Subject: Re: Q: Removal of bias
Date: Mon, 08 Nov 1999 22:39:41 +0100
Scott Nelson wrote:
>
> Most of the existing entropy collectors use hash functions.
> I suppose that means the rule of thumb for XOR and
> Von Neumann is "don't use them."
>
> In my opinion, XOR is never useful, or rather,
> anywhere you'd use an XOR, it's better to use a CRC.
> CRC is, after all, nothing more than XOR with feedback.
> Single chip solutions for CRC exist, and cost virtually
> the same as an xor gate. These are mainly used in
> hardware only (no computer or micro-controller) devices.
I believe though that for software XOR has the advantage of simpler
implementation. That simplicity gives also an intuitive feeling
that it works in bias removal, while for CRC that intuition appears
not to easy to gain, I suppose. Does anyone know references of
experimental comparisons of XOR with CRC and hashs?
M. K. Shen
------------------------------
From: [EMAIL PROTECTED] (Bruce Schneier)
Subject: Re: Scientific Progress and the NSA (was: Bruce Schneier's Crypto
Comments...)
Date: Mon, 08 Nov 1999 21:56:19 GMT
On Sun, 31 Oct 1999 11:27:25 -0500, Nicol So <[EMAIL PROTECTED]>
wrote:
>In http://slashdot.org/interviews/99/10/29/0832246.shtml, Bruce Schneier
>says:
>
>>But how much of an edge [the NSA has over the open community]? Until
>>recently, I would have stated unquestionably that the NSA is a decade
>>ahead of the state of the art in cipher design and analysis. Now, I'm
>>not so sure.
>>
>>Over the past five years, there has been a lot of open research in
>>cryptography. ... The best and brightest of the cryptographers are
>>staying in the open academic community, and are not being swallowed up
>>by the NSA ... There is a vibrant academic community in cryptography;
>>people can exchange ideas, share research, build on each other's work.
>>We've seen attacks against the NSA-designed algorithm Skipjack that
>>almost certainly were not known by the NSA. ... We've seen other
>>attacks that, I believe, were not known by the NSA. ... The public
>>research community is now doing cutting-edge research in cryptography.
>>
>>Now this doesn't mean we are better than they are. Certainly the NSA
>>knows more about cryptography than the public community does. They
>>read everything we publish, and we read nothing that they publish.
>>... That imbalance alone will always give them an edge in knowledge.
>>But I think that edge is closing rapidly.
>
>Bruce Schneier seems to suggest that the NSA is not much ahead of the
>open research community. I'm skeptical of that suggestion--I just don't
>think we can reliably tell.
I agree. We cannot reliably tell. I was just giving my thoughts.
Bruce
**********************************************************************
Bruce Schneier, Counterpane Internet Security, Inc. Phone: 612-823-1098
101 E Minnehaha Parkway, Minneapolis, MN 55419 Fax: 612-823-1590
Free crypto newsletter. See: http://www.counterpane.com
------------------------------
From: John Kennedy <[EMAIL PROTECTED]>
Crossposted-To: alt.military,talk.politics.misc,talk.politics.crypto
Subject: Re: Signals From Intelligent Space Aliens? Forget About It.
Date: Mon, 08 Nov 1999 17:12:20 -0500
On 8 Nov 1999 20:27:29 GMT, [EMAIL PROTECTED] (Bill Unruh) wrote:
>National Security necessitates that we must assume that there are no
>friendly ghosts. We need to spend at least 10 billion a year on anti
>ghost weapons. Much more important than protecting against space aliens.
>(ghosts are here already and they have a much greater insight into how
>we work and what our weaknesses are.)
Who ya gonna call?
NSA!
(I an't 'fraid of no spooks!)
-
John Kennedy
The Wild Shall Wild Remain!
http://members.xoom.com/rational1/wild/
------------------------------
From: John Kennedy <[EMAIL PROTECTED]>
Subject: Re: Doesn't Bruce Schneier practice what he preaches?
Date: Mon, 08 Nov 1999 17:32:40 -0500
On Mon, 08 Nov 1999 21:49:29 GMT, [EMAIL PROTECTED] (Bruce
Schneier) wrote:
>On Mon, 01 Nov 1999 07:39:14 -0500, John Kennedy
><[EMAIL PROTECTED]> wrote:
>
>>>If that's all Schneier meant, then he's wrong. Just knowing the algorithms
>>>used is not enough. You have to know that they were put together correctly,
>>>for example, that any random number generators used were not chilled, that
>>>any keys created were not chosen with malice, that no key bits were being
>>>leaked somehow.
>
>This is all true.
>
>>>Schneier knows all this. That's why I suspect you're misinterpretting him.
>
>I agree. I was probably misinterpreted. Wouldn't be the first time.
>
>>Just so. The only thing I can figure is that he doesn't really
>>consider Password Safe a security tool. But it is positioned as one
>>and the use of Blowfish would strongly imply that it is one.
>
>It is. And I will release source code for the next version.
Can't say fairer than that.
-
John Kennedy
The Wild Shall Wild Remain!
http://members.xoom.com/rational1/wild/
------------------------------
From: "Nicholas Cole" <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp,comp.security.pgp.discuss
Subject: which international version
Date: Mon, 8 Nov 1999 22:39:45 -0000
The FTP server of the PGPi site in the Netherlands seems to contain two
versions of PGP 6.5.1 for international use.
PGPi is the version we know and love, although it seems to have been signed
by Imad this time around.
PGP int is an International Freeware version which seems to me to be
identical to the PGPi version (even down to using RSA keys) but which seems
to have been produced by the company which produces the versions for
PGPinternational.
Can anyone think of valid reasons for running one rather than the other?
NC
ps. Apologies if this message appears twice.....bug in my server, I think
------------------------------
From: Benjamin Valenti <[EMAIL PROTECTED]>
Subject: Encryption Placement
Date: Mon, 08 Nov 1999 17:43:22 -0500
This is a cryptographically signed message in MIME format.
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I am aware that there are three OSI layers where encryption is
implemented: application, network, and data-link layers. What are the
differences between each? What are the reason for choosing one over
another? What are the advantages and disadvantages to using one or the
other? If there is a source online, I haven't found it and could use
some help. Please help me or at least point me in the right direction.
Thank you!
--
Benjamin Valenti
_________________________________
BOOZ � ALLEN & HAMILTON INC.
National Security Team
3190 Fairview Park Drive
Falls Church, VA 22042
P: 703/289-5260
F: 703/289-5825
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==============msD5CF7C035465383BC3611EA6==
------------------------------
From: [EMAIL PROTECTED]
Subject: Re: Incompatible algorithms
Date: Mon, 08 Nov 1999 23:09:59 GMT
Hey all,
Mr. Polk, what you are describing is a 'group' function. From AC,
we have the definition of 'closed'
Ek1(Ek2(P)) = Ek3(P)
which seems to match your idea of compatibility. If a particular
algorithm is closed then the set on encryptions form a group. Modern
algorithms must not be a group or they would be useless for multiple
encryption. DES, for one, has been proven to not be a group in "DES is
not a Group" by Campbell and Wiener.
It is typically a very difficult problem to -prove- an algorithm is not
a group. I have not heard of any proofs for the AES candidates.
Also of interest how far an algorithm is from being a group or if it has
sub-groupgs. AC has a good discussion on the topic, great book.
--Matthew
In article <[EMAIL PROTECTED]>,
Max Polk <[EMAIL PROTECTED]> wrote:
> I have a question about the existance of what I call "incompatible"
> algorithms.
>
> If a plaintext message M is encrypted with algorithm E to produce
> ciphertext C, i.e.:
>
> E(M)=C
>
> then there are many algorithms E1, E2, E3, etc. that are "compatible"
> with algorithm E such that the time complexity of breaking E1(E(M)) is
> the same order of magnitude as breaking E(M). That is to say, you
aren't
> adding security by encrypting a message twice when the algorithms are
> "compatible". If "T" is the time to break ciphertext, then:
>
> T(E1(E(M))) is approximately equal to T(E(M))
>
> and if we use "big-oh" notation O as the order of magnitude of the
time
> complexity to break ciphertext, then
>
> O(E1 x E) = O(E).
>
> For example, algorithm E is a simple letter substitution, and
algorithm
> E1 is a different simple letter substitution. In this case, E1 and E
are
> 100% compatible in both order of magnitude of time complexity as well
> as time complexity itself. There is an algorithm E2 that is a simple
> letter substitution representing the combination of E1 and E.
>
> My question is whether there exists "incompatible" algorithms E and E1
> such that there exists no E2 that is a composite of E1 and E:
>
> E2(M) = E1(E(M))
>
> whose order of magnitude to break the ciphertext is the same as the
order
> of magnitude to break the ciphertext produced by applying E then E1 to
> the plaintext. That is:
>
> O(E2) != O(E1 x E)
>
> If there exists such a pair of algorithms E and E1, then encrypting a
> message with one then the next algorithm is an order of magnitude more
> difficult to break than any existing equivalent composite algorithm.
>
> If these algorithms exist, then they are "incompatible" in the sense
that
> one cannot obtain a composite algorithm equally difficult to break.
> Stated another way, applying incompatible algorithms make breaking the
> resulting ciphertext at least an order of magnitude higher.
>
> Furthermore, if it can be proven that such "incompatible" algorithms
> exist, then we can explore the possibility of finding a mathematical
> inductive proof to show the existence of a chain of incompatible
> algorithms. For example, there exists no E3 such that
>
> O(E2) > O(E1 x E)
> and
> O(E3) > O(E2 x E1).
>
> Any attempt to break a chain of such "incompatible" algorithms then
grows
> in order of magnitude at each step to such a degree of complexity as
to
> make the ciphertext arbitrarily secure.
>
> If this is all true, it may be possible to make the time complexity of
> breaking the ciphertext 10 to the power of n where n equals the number
of
> steps in the chain.
>
> In this case, each additional algorithm applied makes the solution
grow
> very rapidly. Only 10 algorithms applied successively, each taking 10
> seconds to break, results in a solution time of 10 to the power of 10
> seconds, or about 316 years.
>
> Has any research been done on the existence of "incompatible"
algorithms,
> especially in the context of producing arbitrarily secure ciphertext?
>
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Before you buy.
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