On Fri, 19 Apr 2002, Leif K-Brooks wrote:
I have a website where people can signup. Some jerk just made a program
that cheats by signing up automaticly and transfering what he gets when
he starts (you can get virtual money in my game). Does anyone have code
to stop automatic signups? I would write it, but he's about to
distribute his program, which would create quite q mess and unbalance
the game. Thanks if you can help!
To defeat a program you need to come up with something that only a person
can do.
One idea would be to generate a 3-digit number and use GD to display it as
a GIF. Randomly vary the offset and colors so he can't just hash out all
the possibilities. Display the GIF image, and require that the user look
at it and enter that number in order to have their registration processed.
This works because people's brains are very good at pattern recognition
but computers are awful at it.
miguel
--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php
