Cryptography-Digest Digest #713, Volume #9 Sun, 13 Jun 99 15:13:02 EDT
Contents:
Re: Slide Attack on Scott19u.zip (SCOTT19U.ZIP_GUY)
Re: OTP is it really ugly to use or not? (fungus)
Re: Prime number generators... (David A Molnar)
Re: Slide Attack on Scott19u.zip (SCOTT19U.ZIP_GUY)
"Breaking" a cipher (Bernie Cosell)
Re: RC4 Shell Extension / COM Server ([EMAIL PROTECTED])
Re: Prime number generators... ([EMAIL PROTECTED])
Re: differential cryptanalysis (Rod Ramsey)
quick notice ([EMAIL PROTECTED])
Re: Slide Attack on Scott19u.zip ([EMAIL PROTECTED])
----------------------------------------------------------------------------
From: [EMAIL PROTECTED] (SCOTT19U.ZIP_GUY)
Subject: Re: Slide Attack on Scott19u.zip
Date: Sun, 13 Jun 1999 17:11:09 GMT
In article <7k0et9$14o$[EMAIL PROTECTED]>, [EMAIL PROTECTED] wrote:
>In article <[EMAIL PROTECTED]>,
> fungus <[EMAIL PROTECTED]> wrote:
>> One thing is when a person is willing to discuss algorithms and
>> methods.
>>
>> Another thing is when somebody goes on and on about a program with
>> no published algorithms, methodology, or reasoning behind it, just
>> a big pile of messy C code for us to inspect if we can be bothered.
>>
>> D. Scott has been pushing scott19 for about a year now. He claims
>> it's the answer to the NSA and that things like PGP shouldn't
>> be trusted. Then, as soon as somebody looks at it seriously it
>> falls apart.
>>
>> It happened with scott16u, the result was scott19u. It happened with
>> scott19u and I have a horrible feeling that the "answer" will be
>> scott20u. The process will start all over again.
>
>Well I learnt. I wrote the first simple cipher. I didn't like it,
>plus david wagner broke it (without round keys). So I wrote the newer
>simple cipher. It requires far less ram and has a better design. The
>thing is I understand why the first one was broken, I didn't just re-
>invent the wheel (or problem in this case).
>
>I actually understood the problem with the PHTs... maybe Dave Scott can
>learn about efficient algorithm design? Maybe he will learn, I think
>we should grant him a little patience. He thinks he is the be-all in
>the world. Let him mature a bit and maybe he could contribute
>usefullness.
>
>My new cipher is at http://mypage.goplay.com/tomstdenis/simple2.c
>
>As I said it's much easier to follow then my first. It's basically a
>UFN but has diffusion in both directions. It relies on mixing add/xor
>and the sboxes from CAST-128 for security. It includes a variable
>length key schedule as well.
>
>It probably could be broken but I hope to learn something (like I did
>with the first) from it.
>
>(BTW I gave up writing papers as most of my ideas are lessons not
>actual ciphers that could be used. The C code is clean and easy to
>follow so most people can analyze it fairly quickly)
>
>Tom
Tom you are don't seem to understand that I do learn. You are jumping
in on this thread as a jhonny come lately. Mr BS and Mr Wagner have
a large hatred for people that are not in the crypto click. I have done
everything possible to help these individuals with my code. They have
the time to say its broken. But never the time to do an honest evaluation.
They only comment on ameture stuff that they can easily break. Hang
around this group for a few years and you will see.
As for my style it is my style and the source code is inculded if you
would get off your high horse even a newcomer that you could follow the
code but you have to think and use your brain a little. So give it a try.
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: fungus <[EMAIL PROTECTED]>
Subject: Re: OTP is it really ugly to use or not?
Date: Sun, 13 Jun 1999 19:20:03 +0200
[EMAIL PROTECTED] wrote:
>
> In article <[EMAIL PROTECTED]>,
> fungus <[EMAIL PROTECTED]> wrote:
> > eg. RC4.
>
> Wrong
Read the original post again...I never said RC4 was uncrackable,
I gave it as an example of a pseudo-OTP.
--
<\___/>
/ O O \
\_____/ FTB.
------------------------------
From: David A Molnar <[EMAIL PROTECTED]>
Subject: Re: Prime number generators...
Date: 13 Jun 1999 16:42:15 GMT
James Pate Williams, Jr. <[EMAIL PROTECTED]> wrote:
> On 13 Jun 1999 15:39:27 GMT, Krunoslav Leljak <[EMAIL PROTECTED]>
> wrote:
>>It seems that prime number generators of all numeric libraries
>>OCCASIONALY hang slower computers. Is that happening to
>>somebody else?
> When I had a Pentium I 90 MHz machine with 16 MB of RAM F-Secure SSH
> used to hang-up when I tried to generate a RSA key greater than
You know, if this is true, then it's really really sad.
A custom version of PGP (anyone remember Nation Spanning Assurance
2.9 ??)used to generate
2048-bit public key pairs just _fine_ on my old _286_. Granted,
it took fifteen minutes, but it worked. and we liked it!
-David
> 512-bits. Now that I have a Pentium II 450 MHz with 128 MB of RAM this
------------------------------
From: [EMAIL PROTECTED] (SCOTT19U.ZIP_GUY)
Subject: Re: Slide Attack on Scott19u.zip
Date: Sun, 13 Jun 1999 17:28:59 GMT
In article <7k0g8r$1ig$[EMAIL PROTECTED]>, [EMAIL PROTECTED] wrote:
>In article <7k0c8k$21im$[EMAIL PROTECTED]>,
> [EMAIL PROTECTED] (SCOTT19U.ZIP_GUY) wrote:
>>
>> Actually you are lying it never happened with scott16u. I made
>scott19u
>> since it was the largest size that could have a key that could cover
>any
>> possible single cycle S-table of 19 bits. Why do you have to ly and
>if you
>> read Horst's last comment he says it does not fall apart under the
>basic
>> Slide Attack. Yet assholes like you keep remembering the partial
>comments
>> of the spammer mr BS and David Wagner who consider it dead yet don't
>> have the time to look at it.
>> I am not a kiss ass false crypto god that is afraid some ametuer is
>going
>> to shoe them up. When can ass holes like you get that through your
>thick
>> head. Again for you 'SCOTT16U" was never broken and I have a contest
>> for it with a thousand dollars that expires on Nov 11 this year. Last
>year
>> one of the crypto gods called the contest a joke since it was a short
>time
>> the asshole went in to say not enough time. I had to write the
>asshole to
>> explain that it didn't expire to NOV 11 1999 needless to say the
>asshole
>> never correct his error. They like to make sweeping statements to
>mislead
>> but seldom clean up the mis truths they spread. And assholes like you
>> continue to spread there lies.
>
>
>You still don't get it do you? Too bad. You think the whole point of
>this is to have some super duper encryption algorithm. I think it is a
>means to advance cryptography. I am by no means a leader here. I have
>lots to learn, but I am. You profess that your algorithm is super
>duper strong, perhaps it is, but really what is so good about it?
>
>Many ciphers are practically secure (i.e require over 2^128 work to
>crack etc...) and are much easier to use then yours. The point of
>cryptography in my eyes is to prevent (or deter) fraud. I really don't
>care what you had for lunch yesterday, neither does the NSA. If your
>algorithm cannot be mass produced in any way, shape or form then what
>is the point?
>
>I can build a secure block cipher too, just give me 2^67 bytes of ram
>and 2^64 time and I will be with you. But that's not the point. The
>idea is to take 2^10 bytes of ram and 2^5 time... etc...
>
The idea for me any way is to write something that so not to slow
that should run on a PC and give people the maximun secrity in the
encrypted result and not to see how close I can skate to making the
key short. What you don't understand is that once one has a keyenc.key
file you can use your short pass phrase as the key much as in PGP
I hope the consept it not over your head.
>So get off your high horse and realize that you don't know everything.
>Neither does David Wagner, the infamous Bruce and even me. If you can
If you read the "infamous Bruce" posts you can see the stuff he writes.
He clains ametuers can't write or come up with good encryption methods
he is the one on the high horse. Yet he critizes other with out looking
because of his ego he thinks he knows all. ALso if you bother to read his
posts he had a comment that it is much harder to design an emcryption
method with a large key so maybe you can't do it. But I feel that maybe
you can. As far as the "Slide Attack" goes there was a post about Blowfish
and this attack. I don't know if the post was true. But if it was how could
the great cypto god design such a poor cipher. The reason I doubt if it was
true is becasue both guys are in the club and need to pat each other on
the back know and then so I doubt if the break is true. Because if it was
true they would most likely hid the facts or at least down play the
significance of it.
>learn (or appreciate other peoples views) something from your
>experiences then well I would be more then happy to tag along and help
>out. But you are so set in your ways that I don't know why people
>(including me) even respond to you.
>
>BTW a single message is not much of a contest. What if I found a break
>(just hear me out) that requires 2^30 chosen plaintexts. It's still a
This contest is more fair than the IDEA contest run awhile back if
you bother to take a look. But then your new to this game and
don't know much. But you catch on quick when it comes to trying
to look good but you don't know enough yet. Sice you are still wet
behind the ears.
>break but I cannot use that to crack your one message. I would put the
>1000$ towards the first person to break your cipher. and how do we
>know that the 'ciphertext' is really not just random bytes thrown
>together?
>
>Tom
Tom do you have a 1000 dollars that you can put towards a contest.
Do you think it is ethical to run a contest and offer a prise with out
having that much spare cash. I don't think that would be ethical but
maybe you ethical level is lower than mine.
Also you don't know if the contest is random jiberish but the
last ones where not. I have been posting for years I am not
about to run a contest and not have the solution file. However
your new with no history you might run such a contest.
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] (Bernie Cosell)
Subject: "Breaking" a cipher
Date: Sun, 13 Jun 1999 16:24:22 GMT
In a bunch of threads [mostly fueled by PR from the EFF], folks keep
talking about "breaking" DES" and "breaking RSA" and such. There's a
semantic problem here for me that I need some help with:
Every key-based system is "breakable". The only interesting data on that
is the "cost/time" curve. If someone finds a more efficient search, or the
cost of hardware comes down, the cost/time curve can shrink and change
shape, but there's been no fundamental change in the strength of the
cryptosystem, at the abstract level. I'd guess that there have been
installations that can decrypt a single DES-encrypted message in under an
hour for decades, big deal... of course the *cost* of doing such a thing
has come down wildly, but [IMO] that was a largely expected result [given
Moores' law, you'd expect the cost to decrypt within a particular time
limit to halve every year and a half or something like that]
As a practical matter, I always thought that Information Managers had to
estimate a similar graph: in this case it is the dollar value of their
information if it is disclosed within particular time frames. Then you
match your disclosure-cost against the cryptosystem-breaking-cost and pick
a system [or key size or whatever] appropriately. [yes, there are more
considerations... I'm just focusing on this one aspect at the moment].
Anyhow, I don't consider that activity, nor the shrinking of the decrypt
cost/time curve to be "breaking" a cryptosystem. It is a valuable and
important exercise, so that we can keep tabs on the cost/time to decrypt
curve, but I don't consider _getting_ datapoints for that curve as
"breaking".
In my odd semantic world, "breaking" a cryptosystem means finding a
weakness in the underlying algorithm that actually _decreases_the_work_ to
decrypt [not merely making doing the same work faster or cheaper, which is
just like checking the NYSE to get todays' value for one of your stocks,
getting today's value for a datapoint on the cost/time decrypt curve].
There are _big_ breaks, that might involve finding a way to lessen the work
to decrypt from exponential to polynomial; and there are littler breaks
[e.g., that just reduce the exponent some]. But unless a discovery
*intrinsically* weakens a cryptosystem, I don't consider it to have been
"broken".
Does this usage jibe with any of you, or am I just out in left field by
myself here??
/Bernie\
--
Bernie Cosell Fantasy Farm Fibers
[EMAIL PROTECTED] Pearisburg, VA
--> Too many people, too few sheep <--
------------------------------
From: [EMAIL PROTECTED]
Subject: Re: RC4 Shell Extension / COM Server
Date: Sun, 13 Jun 1999 16:43:20 GMT
In article <7k0ka0$2n2$[EMAIL PROTECTED]>,
[EMAIL PROTECTED] wrote:
> http://community.wow.net/grt/rc4se.html
> 128 bit RC4 (TM) Encryption
> Shell Extension and COM Automation
> Server for Windows 95/98/NT4.
> 115 KB.
> Freeware. Freely distributable.
I installed it and it works great. I have some suggestions and
questions.
Suggestions:
1) It should be clear what operation you are performing. In the case
of RC4 they are both the same so there should be no 'encrypt/decrypt'
just process.
2) There should be a dialog either displaying the process or prompting
the user to tell them it's done
Questions:
1) What do the check boxes do? Encrypt/decrypt is the same thing.
What type of compression is it?
2) What passwd hashing algorithm does it use?
3) What type of protection (i.e virtual mem clearing) does the app
perform?
Tom
--
PGP public keys. SPARE key is for daily work, WORK key is for
published work. The spare is at
'http://members.tripod.com/~tomstdenis/key_s.pgp'. Work key is at
'http://members.tripod.com/~tomstdenis/key.pgp'. Try SPARE first!
Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't.
------------------------------
From: [EMAIL PROTECTED]
Subject: Re: Prime number generators...
Date: Sun, 13 Jun 1999 16:47:59 GMT
In article <7k0jbf$qr8$[EMAIL PROTECTED]>,
Krunoslav Leljak <[EMAIL PROTECTED]> wrote:
> It seems that prime number generators of all numeric libraries
> OCCASIONALY hang slower computers. Is that happening to
> somebody else?
Well if ALL algorithms hang ALL slow computers, and NO fast computers
maybe it just takes to long?
It really depends on the platform and algorithm used to test for
primality. I know in PGP it takes about 20 seconds max to gen the keys
on my MII 300 so I would imagine on smaller machines it could take
quite a bit (Hmm makes me want to get a PIII...)
Tom
--
PGP public keys. SPARE key is for daily work, WORK key is for
published work. The spare is at
'http://members.tripod.com/~tomstdenis/key_s.pgp'. Work key is at
'http://members.tripod.com/~tomstdenis/key.pgp'. Try SPARE first!
Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't.
------------------------------
From: [EMAIL PROTECTED] (Rod Ramsey)
Subject: Re: differential cryptanalysis
Date: 13 Jun 1999 17:47:25 GMT
>[EMAIL PROTECTED] wrote:
>> ps. I know this is not the subject of sci.crypt, but where can I get a
>> prog to view .ps files under ugh.. win '95
All the files on this particular site are available in PDF (acrobat) format
anyway. I find that much easier to deal with. Seems most technical paper
sites are beginning to offer the choice.
Rod
------------------------------
From: [EMAIL PROTECTED]
Subject: quick notice
Date: Sun, 13 Jun 1999 17:01:30 GMT
=====BEGIN PGP SIGNED MESSAGE=====
Hash: SHA1
In case anyone wants to send me PGP mail or verify my signatures. My
key is now at
my new site. If you already have my 'work' key then you are set. I
am not using the spare
anymore but I still have it just in case.
Thanks for your time,
Tom
- --
PGP key is at:
'http://http://mypage.goplay.com/tomstdenis/key.pgp'.
=====BEGIN PGP SIGNATURE=====
Version: PGPfreeware 6.0.2i
iQA/AwUBN2Pi8cnv2fqXBZQeEQJzfwCfT1aD4dlWFXuPpkmDJVm83S27BxsAn3EH
0qyGpa3o099juscI5tC+3Q6l
=Gjx5
=====END PGP SIGNATURE=====
Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't.
------------------------------
From: [EMAIL PROTECTED]
Subject: Re: Slide Attack on Scott19u.zip
Date: Sun, 13 Jun 1999 17:53:36 GMT
In article <7k0m86$1626$[EMAIL PROTECTED]>,
[EMAIL PROTECTED] (SCOTT19U.ZIP_GUY) wrote:
> The idea for me any way is to write something that so not to slow
> that should run on a PC and give people the maximun secrity in the
> encrypted result and not to see how close I can skate to making the
> key short. What you don't understand is that once one has a keyenc.key
> file you can use your short pass phrase as the key much as in PGP
> I hope the consept it not over your head.
Geez let me see if I can understand. Sloppy + Slow = Good ?
> If you read the "infamous Bruce" posts you can see the stuff he
writes.
> He clains ametuers can't write or come up with good encryption methods
> he is the one on the high horse. Yet he critizes other with out
looking
> because of his ego he thinks he knows all. ALso if you bother to read
his
> posts he had a comment that it is much harder to design an emcryption
> method with a large key so maybe you can't do it. But I feel that
maybe
> you can. As far as the "Slide Attack" goes there was a post about
Blowfish
> and this attack. I don't know if the post was true. But if it was how
could
> the great cypto god design such a poor cipher. The reason I doubt if
it was
> true is becasue both guys are in the club and need to pat each other
on
> the back know and then so I doubt if the break is true. Because if it
was
> true they would most likely hid the facts or at least down play the
> significance of it.
The break on blowfish was against a variant which had the round keys
removed. Of course you would know that if you read the paper, you know
nothing waste of space. (Revenge is bittersweet...)
> This contest is more fair than the IDEA contest run awhile back if
> you bother to take a look. But then your new to this game and
> don't know much. But you catch on quick when it comes to trying
> to look good but you don't know enough yet. Sice you are still wet
> behind the ears.
Well I just got out of the shower, how did you know that? Most
contests have a purpose. The DES challenge was to show that the key
could be searched really quickly. The Twofish team put $10000 dollars
where their math is. They put the money towards the first person to
break the cipher, not a message. You could do the same.
> Tom do you have a 1000 dollars that you can put towards a contest.
> Do you think it is ethical to run a contest and offer a prise with out
> having that much spare cash. I don't think that would be ethical but
> maybe you ethical level is lower than mine.
> Also you don't know if the contest is random jiberish but the
> last ones where not. I have been posting for years I am not
> about to run a contest and not have the solution file. However
> your new with no history you might run such a contest.
I don't need to pay people to talk to me. If I want to break my own
algorithm I will ask for comments and work it out myself. Unlike you I
ask for help and am receptive. David helped point out a method of
breaking my simpler cipher (the first one without round keys), now I
can see why round keys are very important. etc...
I think you should really just calm down. This is suppose to be about
cryptography and not who you can attack next. We all have tried to
help you, and you insist on being a mean bitter person. I maybe the
youngest poster here but I am no fool. Good day to you sir.
Tom
--
PGP key is at:
'http://http://mypage.goplay.com/tomstdenis/key.pgp'.
Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't.
------------------------------
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