Dean Wilson@UnixDaemon: ... It's not even close to relevant.

Sat, 15 Jan 2005

Russian Roulette -- Bash Style
There are a list of things you don't want to see in your Unix machines start up scripts but one of the leaders has to be a snippet like this:

[ $[ $RANDOM % 6 ] == 0 ] && rm -rf / || echo "You live. For now."

Before we look at what the chunk of code is supposed to actually do it's worth mentioning that $RANDOM is a built-in shell variable. Each time it is read it will return a random integer between 0 and 32767. It's worth noting that although it's called $RANDOM it is no where near random enough to be used in any sensible crypto or security code / system.

Now back to the code itself, every time it runs you have a one in six chance of wiping your machine. It's not nice and once you know about $RANDOM it's not all that clever either.

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Posted: 2005/01/15 11:40 | /codinghorrors | Permanent link to this entry | This entry + same date

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