Re: getting around Ken Thompson's compiler Trojan

From: Casper H.S. *** (Casper.***@Sun.COM)
Date: 01/22/03 

From: Casper H.S. *** <Casper.***@Sun.COM>
Date: 22 Jan 2003 22:19:36 GMT

christopherlmarshall@yahoo.com (Chris Marshall) writes:

>First, write a program to obfuscate the source code of any other program
>by randomizing the variable and function names, as well as the names
>of the source code files.

The compiler could recognize itself from the resulting parse
trees which are abstracted from the names of variables.
(And the trojaned compiler would need to accept a certain "fuzz"
or the compiler could never evolve)

No amount of obfuscation based on names of functions/variables
would work. You would need to restructure the code and don't
forget to rename that source file too :-)

Casper 

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