A notion

["Justin R. Smith" <jsmith@mcs.drexel.edu>]

It occurred to me that custom versions of software can be more secure
than standard versions because various exploits (like stack smashing,
etc.) require precise knowledge of certain sizes and distances in RAM
(for instance, the distance from the end of a buffer to the return
point...).

Isn't it possible to develop a "randomizing C compiler" that randomly
varies these distances every time it compiles a program? No two compiles
of the same source code would be exactly the same (but they would
execute the same way).

This might involve inserting small random-sized blocks of dead code, or
doing returns from subroutines through a level of indirection (i.e.,
putting the actual return at some random location in the object code
with a branch to it).

Done right, this might not degrade performance significantly.


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