[Cryptography] Can crypto implement OS/FS protections ?

[Henry Baker]

I've been wondering how many of the current OS/page table and file
system protections can be theoretically implemented via cryptography.

I'm ignoring O(1) -- constant -- factors, so the CPU could conceivably be
executing public key operations for every instruction cache fill operation.

For example, any *return addresses* could conceivably be stored on the
stack and cryptographically signed in such a manner that they couldn't be
spoofed by an attacker.

I have to believe that someone, somewhere has already thought about
this problem.

I'm not worried about performance on current HW, because HW in the
next decade will be changing dramatically in any case.