On Sat, Jul 10, 2021 at 9:55 PM David Edelsohn dje.gcc@gmail.com wrote:
On Sat, Jul 10, 2021 at 2:45 PM Maamoun TK maamoun.tk@googlemail.com wrote:
On Fri, Jul 9, 2021 at 10:08 AM Niels Möller nisse@lysator.liu.se
wrote:
Maamoun TK maamoun.tk@googlemail.com writes:
My concern is if the program terminates then the operation system will deallocate the program's
stack
without clearing its content so that leftover data will remain
somewhere
at
the RAM which could be a subject for a memory allocation or dumbing
by
other programs.
I think the kernel is responsible for clearing that memory before handing it out to a new process. If it didn't, that would be a huge security problem. I'm fairly sure operating systems do this correctly. (And I would be a bit curious to know of any exceptions, maybe some embedded or ancient systems don't do it?)
You are right, modern operating systems are supposed to have this functionality but accessing some program's memory is pretty easy
nowadays,
I think it's a good practice to clean behind the cipher functions for
what
it makes sense and whenever possible.
In another topic, I've optimized the SHA-512 algorithm for arm64 architecture but it turned out all CFarm variants don't support SHA-512 crypto extension so I can't do any performance or correctness testing for now. Do you know any CFarm alternative that supports SHA-512 and SHA3 extensions for arm64 architectures?
There is a new AArch64 system in the GCC Compile Farm that has not been installed yet. That system might provide the SHA-512 support. It will have an Ampere eMAG processor supporting ARMv8.
Thanks, David