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Re: Adding support for LZIP to dpkg, using that instead of xz, archive wide



Joerg Jaspert <joerg@debian.org> writes:

> On 14026 March 1977, Vincent Lefevre wrote:
>
>>> > contents that match in size and sum(1). I did it just with an
>>> > editor, ddrescue and data from /dev/urandom, by brute force, without
>>> > any knowledge about the algorithm of sum. And I did it not once, but
>>> > twice.
>>> sum(1) just gives a 16-bit checksum! So, it suffices to generate
>>> N*65536 random compressed tarballs to get around N collisions with
>>> a given file. Then the only problem is to get the right size, but
>>> if one has random input, it is (almost) not compressible, so that
>>> one will get "almost" the same size for each tarball. By controlling
>>> how compression is done to reach the right size, this should even be
>>> easier.
>> The following script gives lzip collisions after a few seconds between
>> arbitrary lzip tarballs. This is easier that a collision with a fixed
>> tarball because of the birthday paradox. But one can do something
>> similar by going to at most a few millions to get a collision with
>> some given tarball of about 64 KB.
>
> Is it only me thinking it now or is this really gone over way into the
> comedy section? Why isn't this on -curiosa?

NO, it definitely isn't just you -- and the rest of your post was spot on too.

Please stop this nonsense forthwith.

Cheers, Phil.
-- 
|)|  Philip Hands  [+44 (0)20 8530 9560]  HANDS.COM Ltd.
|-|  http://www.hands.com/    http://ftp.uk.debian.org/
|(|  Hugo-Klemm-Strasse 34,   21075 Hamburg,    GERMANY

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