[Savannah-register-public] [task #10138] Submission of Swiss army knife of file signature checksum tool

[Mario Castelán Castro]

Follow-up Comment #3, task #10138 (project administration):

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256

February 7th 2010 in GNU Savannah task 10138: "Submission of Swiss
army knife of file signature checksum tool"

Thanks for your fast response Tong.

>As for crc32.c, the zlib crc32 function can't be used directly since
>it is using the 0xFFFFFFFF pre & post condition [...]

Do you need to use an particular polynomial for the CRC?

The program will not interfact to libogg or any other, true?, then you
can use any polynomial for the CRC, or use another algorithm instead.

I'm not sure, but I think MD4 is faster than CRC32 in software since
it is not complex and it works by wide blocks, not by stream like CRC.
Apart it result is wider, so random colisions are more unlikley than
with CRC.

The above is just technical advice, you are not required to use any
particular algorithm to host in savannah.  Patented ones can't be used
in free software, since they impose propietary, unacceptable
restictions, there are a few exeptions like CAST4, wich is patented
but can be freely used.

>However, there is no copyright and licensing info in source. I've
>written to the author since, but haven't get reply yet:

Note that in GNU project (And therefore in Savannah, part of the GNU
project) we don't support the open source software but the free (As in
freedom) one, plese read
http://www.gnu.org/philosophy/open-source-misses-the-point.html.

You must label, at least inside savannah your projects as free, that
is a requirement: https://savannah.gnu.org/register/requirements.php.

Remember, Copyright don't cover ideas by itself but the manner they
are expressed.  You can rewrite any software (Unless it is cover by
patents) keeping the same algorithm and design, If the result don't
seems related to the "original" version then you can assign the
copyright of the revised version to you, and release it under a free
licence of your choice (I suggest the GNU GPL of course, but that is
up to you).

So if the author of the CRC implementation you want to use don't
release it as free software, or you don't want to wait, rewrite it
from scratch, or use another hash instead (Like sugessted above).

Regards.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)

iEYEAREIAAYFAktvQfQACgkQZ4DA0TLic4hCwgCfT2zqfLJ9HsRomF4p2uY0SHSM
HJcAn1p08Tug6WAu22OrLTvufUpsnmE/
=gu4P
-----END PGP SIGNATURE-----


    _______________________________________________________

Reply to this item at:

  <http://savannah.gnu.org/task/?10138>

_______________________________________________
  Mensaje enviado vai/por Savannah
  http://savannah.gnu.org/