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Re: Steganography - Encryption challenge


2004-09-08 05:59:55 AM
delphi150
Craig Stuntz [TeamB] writes:
Quote
I am not talking about your contest in particular, but "crack my
cyphertext" challenges (which are quite common) in general, and why
they begin to sound tiresome pretty quickly.
I am positive Dennis already knows that.
In general, people post these kinds of challenges because they think
"this can not be so hard", eventually gets it trashed, and learns a
valuable lesson from the experience. It is 99.999% of all cases just a
learning curve phenomenon. It is more effective to learn by reading all
of the articles that are available on the web, though, at least if you
want to do it right. Just some general advice. <g>
--
Henrick Hellström
www.streamsec.com
 
 

Re: Steganography - Encryption challenge

"James" <sundiskAThotpop.com>writes
Quote
Steganography sounds very interesting.Where can I find some good examples
that do that? I am not interested in the encryption but how you put the
text
in the picture. Can it be any type of image or just bmp?
I used PNG because the file format's architecture is intended to be
extended.
You can simply define your own "chunk type" and register it with the PNG
object.
www.libpng.org/pub/png/spec/
I believe you can do things with jpg as well, but I haven't looked into
that...
-d
 

Re: Steganography - Encryption challenge

"Ingvar Nilsen" <XXXX@XXXXX.COM>writes
Quote
The big question, as Craig points out, is to what extent such an
algorithm is usable. And to find out that, original source, encrypted
data and the algorithm has to be available all together.

Then it becomes interesting :)
I have heard that argument a thousand times.
If I gave you the algorithm and the source, you still wouldn't be able to
crack a single encrypted file given even one hundred encrypted examples; the
only thing that would accomplish, is that that algorithm is no longer
secret.
I don't wish to share the algo, so no amount of bullying or derision will
change that...
You do have the opportunity to win USD $500, however.
<g>
-d
 

Re: Steganography - Encryption challenge

Ingvar Nilsen writes:
Quote
Is is not difficult to write an encryption algorithm using Delphi that
is extremely difficult to crack. I have written several myself.
Indeed:
lCT := EncryptString(MustFindCipherClass(caRijndael,cmCBC),
lKey,lIV,lPT);
Quote
The big question, as Craig points out, is to what extent such an
algorithm is usable. And to find out that, original source, encrypted
data and the algorithm has to be available all together.

Then it becomes interesting :)
No.
The chances that the algorithm would turn out to be usable if submitted
to public review, are about as small as the chances that someone without
any medical education or experience would be be able to perform a
successful brain surgery.
I don't state this out of disrespect for Dennis. I state this because it
is a fact. No one does this right the first time they try.
--
Henrick Hellström
www.streamsec.com
 

Re: Steganography - Encryption challenge

Quote
It is even more interesting to put pictures in text :)
This message contains the screen shot of the new Delphi 9 splash screen,
try to find it..
This is a encoded message for you:
NAD voitaloisn wlil be dlaet wtih siwflty and hralshy.
Hehe!
--
Anders Ohlsson - Borland Developer Relations - bdn.borland.com/
Borland Software Corporation - www.borland.com/ - Excellence Endures
Enabling our customers to move into the future without abandoning their past
blogs.borland.com/ao/
homepages.borland.com/aohlsson/blog_beta/
 

Re: Steganography - Encryption challenge

Quote
>NAD voitaloisn wlil be dlaet wtih siwflty and hralshy.
And violations will dealt with swiftly and rashly
I feel like that detective "Monk".
 

Re: Steganography - Encryption challenge

"Dennis Landi" <XXXX@XXXXX.COM>writes
Quote
I feel like that detective "Monk".


that is, obsessive-compulsive.
 

Re: Steganography - Encryption challenge

Quote


And violations will dealt with swiftly and rashly

Yur'oe epxireecnnig smee dtaa lsos...
www.cafepress.com/crazyswedeshop
:)
--
Anders Ohlsson - Borland Developer Relations - bdn.borland.com/
Borland Software Corporation - www.borland.com/ - Excellence Endures
Enabling our customers to move into the future without abandoning their past
blogs.borland.com/ao/
homepages.borland.com/aohlsson/blog_beta/
 

Re: Steganography - Encryption challenge

Quote
"Dennis Landi" <XXXX@XXXXX.COM>writes

>>NAD voitaloisn wlil be dlaet wtih siwflty and hralshy.

And violations will dealt with swiftly and rashly

I feel like that detective "Monk".
Sorry, you haven't won the $500. I believe the upper-case part of Anders
message was significant.
However, lawyers prevent me saying any more on the matter.
[and I claim my free Borland sticker]
Regards,
Roddy
 

Re: Steganography - Encryption challenge

"Roddy Pratt" <roddy at rascular dot com>writes
Quote
>"Dennis Landi" <XXXX@XXXXX.COM>writes
news:XXXX@XXXXX.COM...
>
>>>NAD voitaloisn wlil be dlaet wtih siwflty and hralshy.
>
>And violations will dealt with swiftly and rashly
>
>I feel like that detective "Monk".

Sorry, you haven't won the $500. I believe the upper-case part of Anders
message was significant.

doh!
NDA, of course!
 

Re: Steganography - Encryption challenge

"Anders Ohlsson (Borland)" <XXXX@XXXXX.COM>writes
Quote
>
>
>And violations will dealt with swiftly and rashly
>

Yur'oe epxireecnnig smee dtaa lsos...

You think I am that easily distracted by a casual puzzle encounter?
Your right!
Quote
www.cafepress.com/crazyswedeshop

:)

--
Anders Ohlsson - Borland Developer Relations - bdn.borland.com/
Borland Software Corporation - www.borland.com/ - Excellence
Endures
Enabling our customers to move into the future without abandoning their
past
blogs.borland.com/ao/
homepages.borland.com/aohlsson/blog_beta/

 

Re: Steganography - Encryption challenge

Dennis Landi writes:
Quote
This challenge is simply an educational benchmark for me. Its an
efficient means of proving a few things. One thing that I *hope*
happens is that some smart hacker immediatly cracks the encryption if
such a thing was doable. If such a thing were to happen then I would
gladly pay USD $500 for that valuable lesson.
What on earth would you learn from that?
Is is not difficult to write an encryption algorithm using Delphi that
is extremely difficult to crack. I have written several myself.
Quote
So that you don't misunderstand, the whole point of the challenge is
to see if this encryption is indeed easily crackable.
There is no such smart hacker, and if it is crackable, the only thing
you would learn is that your algorithm is way below average :-)
Quote
It won't prove that is *isn't* crackable, given time, since we would
have to allow time and a documented concerted effort to occur to ever
make that claim, if ever...
In most cases, it is crackable. Depending on the number of available
encrypted files, and the amount of efforts put in.
The big question, as Craig points out, is to what extent such an
algorithm is usable. And to find out that, original source, encrypted
data and the algorithm has to be available all together.
Then it becomes interesting :)
--
Ingvar Nilsen
 

Re: Steganography - Encryption challenge

"Ingvar Nilsen" <XXXX@XXXXX.COM>writes
Quote
It is even more interesting to put pictures in text :)
This message contains the screen shot of the new Delphi 9 splash screen,
try to find it..

No luck, but I did find the new C++Builder 7 splash screen, losslessly
encoded into the last full stop...
But, every decoding is another encoding.... ;>)
- Roddy
 

Re: Steganography - Encryption challenge

"Dennis Landi" <XXXX@XXXXX.COM>writes
Quote

>>NAD voitaloisn wlil be dlaet wtih siwflty and hralshy.

And violations will dealt with swiftly and rashly
And
Wrong.
Quote
rashly
Also wrong.
 

Re: Steganography - Encryption challenge

James writes:
Quote
Steganography sounds very interesting.Where can I find some good
examples that do that? I am not interested in the encryption but how
you put the text in the picture.
It is even more interesting to put pictures in text :)
This message contains the screen shot of the new Delphi 9 splash screen,
try to find it..
--
Ingvar Nilsen