Randy Kramer wrote:
> On Friday 29 August 2008 06:41 am, Michael Morin wrote:
>> If a "hacker" has write access to your end user's files (including the 
>> program you gave them), they can change it however they want.  There's 
>> nothing you can do there.  There are some methods involving 
>> cryptographically signed binaries and such, but there are always way 
>> around it.
> 
> Another approach to the problem is to strictly separate code from data (and 
> store all variables and the like separate from the code), then put the code 
> into ROM or similar.
> 
> Randy Kramer

Even that's not effective.  ROM dumps are not difficult to obtain, ROM 
chips are not difficult to replace with flash chips or even an interface 
to your PC.  You also can't really do that with a Ruby program either.

The only semi-effective way I've seen to do this is with gaming 
consoles.  The Xbox will only run signed code.  This is problematic 
though, only people with the correct keys can produce code that will run 
on the Xbox (which Microsoft charges large sums of money for) and it was 
still cracked (at least the first Xbox was).

-- 
Michael Morin
Guide to Ruby
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