Question about mpz_clear
Thu, 19 Jun 2003 10:49:15 +0200
Kevin Ryde wrote:
> "Eric M. Hopper" <firstname.lastname@example.org> writes:
>>Does this clear the memory associated with a given variable zeroed?
>>Is there an easy way to make sure it is?
> mp_set_memory_functions will let you have your own free function.
I am having a slight problem with that. I have ascertained that I often
have a lot of mpsomething with rather short limbs; it would be efficient
to store the limbs contiguous to the 'enveloppe' data; unfortunately,
the free function would then require more info than just the limb
pointer. Is it conceivable to change the library for that? I might do
it, but am not keen on starting a modif that would not be accepted in
the official tree...
>>I'm designing some software that does cryptography, and I would like to
>>ensure that decrypted private keys are lying around in memory in a
>>decrypted state for as little time as possible.
> Lots of gmp routines put operand data on the stack too.
When that happens, is it not just the pointer data that is on the stack,
with the limbs *always* in the malloc arena? (Of course my proposal
would invalidate that!)
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