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I heard /. was good about having 04/01 day jokes, but I didn't think this good.... I love it... the articles, the cookies... best so far is the userfriendly/segfault/bedope
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Four years in jail
No Trial, No Bail
*** FREE KEVIN ***

paraphasing/quoting from Applied Cryptography (pp 14-15)

(NOTE: this example is random Key XOR'd against ASCII text, this is different then the percentages for this contest. This also assumes that the key is small.)

1) Discover the length of the key using process known as counting coincidences.
XOR the cyphertext against itself shifted various numbers of bytes and count those bytes that are equal.

If the displacement is a multiple of the Key length then > 6% of the bytes are equal.

If it is not a multiple then less then 0.4 % are equal.

This is called then index of coincidence. Take you smallest displacment (the one w/ greater then 6%), this is the number we want for step 2

2) Shift the ciphertext by that length and XOR it with itself. This removes the key and leaves you with plaintext XOR'd with the plaintext shifted the lenght of the key (the number we found).

3) The fun part.
English has 1.3 bits of real information per byte, so there is plenty of redundancy in order to find the exact plaintext.

Remember we are only dealing with ASCII here. The percentages are different, but the concepts are the same. Thanks Mr. Schneier!!!
--
Four years in jail
No Trial, No Bail
*** FREE KEVIN ***

paraphasing/quoting from Applied Cryptography (pp 14-15) (NOTE: this example is random Key XOR'd against ASCII text, this is different then the percentages for this contest. This also assumes that the key is small.) 1) Discover the length of the key using process known as counting coincidences. XOR the cyphertext against itself shifted various numbers of bytes and count those bytes that are equal. If the displacement is a multiple of the Key length then > 6% of the bytes are equal. If it is not a multiple then less then 0.4 % are equal. This is called then index of coincidence. Take you smallest displacment (the one w/ greater then 6%), this is the number we want for step 2 2) Shift the ciphertext by that length and XOR it with itself. This removes the key and leaves you with plaintext XOR'd with the plaintext shifted the lenght of the key (the number we found). 3) The fun part. English has 1.3 bits of real information per byte, so there is plenty of redundancy in order to find the exact plaintext. Remember we are only dealing with ASCII here. The percentages are different, but the concepts are the same. Thanks Mr. Schneier!!!
--
Four years in jail
No Trial, No Bail
*** FREE KEVIN ***

Evolution through technology.
I for one think this is great.

I hope the technology isn't hoarded and I hope it doesn't drive poor chicken farmers in to a worse state. But I do like the technology that allows this stuff to happen.

Eventually it means the cures for all sorts of genetic disorders, from alcholism to obeseity. And yes, it does mean that people will be able to pick which color skin/eyes/etc their kids will have. I don't care. Physical appearence does not matter. Discrimination about appearence is the problem. Hopefully racisim will end when people realize that it genetically doesn't matter. (but by that logic it would have already ended.... hmm, if physical appearence was based on a die role and not on your parents...soon it could be...) Anyway I believe that saving lives is worth it.
(i wish there was a spell check)
--
Four years in jail
No Trial, No Bail
*** FREE KEVIN ***

Please correct me if I am wrong, but a glance at this code seems to look like a simple Xor.
P ^ Key = C;
C ^ Key = P;
So all one has to do is figure out the length of the key. There is a method to do that called counting coincidences (breifly explained in Applied Cryptography, a wonderfull book). Then shift the ciphertext, C, by the length of the Key and you effectivly have P ^ (P shifted the length of Key). With this infomation (ASCII ^ ASCII), we should significantly reduce the possible choices and be able to pick the correct plaintext, P.

Or not. Maybe I'm just tired....or missing something. I'll look in to it tomorrow after class if no one has figured it out by then.
--
Four years in jail
No Trial, No Bail
*** FREE KEVIN ***

Our records have stickers with a warning from tipper
'coz they're no good for kids
If we'd get her we'd strip her
--KMFDM

If Gore is the future: Clipper, CDA, and mass censorship will only be the tip of the iceberg.

He is the father^H^H^H^H^H^Hkiller of the vast network of free speach known as the Internet.
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Four years in jail
No Trial, No Bail
*** FREE KEVIN ***

Not only did it get moderated, I plugged in my threshold to -133 and -666 and I didn't see any of them.

I knew it was there, because I read the comments when this article only had one comment on it. Then I went back to coding for a class of mine. Later, I wanted to read your original post, and sure enough they were gone. Had to search for them. (hint: first)

I am wondering if this is worse then the negative scores on posts critical of linux.com
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Four years in jail
No Trial, No Bail
*** FREE KEVIN ***

This charade limits the quality of work (no peer review) and the benifits for workers (no jobs). A more interesting model based on the bounty system is instead of the bounty going personally to you, the money is donated to a preset charity. With this model there is peer review (no incentive to hide code). This might incourage more people to work for free software, thinking that they are helping two things at once.
--
Four years in jail
No Trial, No Bail
*** FREE KEVIN ***