Help - Adding size to a document? -> No security, think differently

[Osamu Aoki]

Hi,

(I send direct reply to OP and Ubuntu intentionally with reason... I am
afraid message from OP may spread a wrong idea.)

I know double posting to ML (Debian and Ubuntu in this case.)  is not
generally considered good.  If the original poster uses Ubuntu, he
should post there only.

On Sun, Nov 23, 2008 at 04:39:19PM +0100, Manuel Gomez wrote:
> Hi, i would like to add more size to a document to avoid hackers. If the
> size is too big, Trojans won't download the archive (it would take days
> and days...)
> 
> How could i do this? I am using "SFX compiler" for join an archive (3
> gb, for example) with my documents, but i would like to know how its
> done.

Although I do not agree his method to be valid one, one can create big
3GB random file by:

 $ dd if=/dev/urandom of=random.bin bs=1024 count=$((3*1024*1024))

For random text file with about 3GB:

 $ dd if=/dev/urandom bs=1024 count=$((1024*1024)) 2>/dev/null | od -t x1 - > random.txt

But if a hacker roots a badly configured system, he can use the
extraction utility to remove junk big one and get files he need.

What one should use is good security measures:
 * well configured system to protect system.
 http://www.debian.org/doc/manuals/securing-debian-howto/index.en.html
 * data encryption technology to make is useless even if a file is stolen.
 http://people.debian.org/~osamu/pub/getwiki/html/ch11.en.html#datasecurityinfrastructure
 http://people.debian.org/~osamu/pub/getwiki/html/ch10.en.html#dataencryptiontips

Cheers,

Osamu