Re: [PATCH 04/12] net/ena: fix build with GCC 12

[Stephen Hemminger <stephen@networkplumber.org>]

On Sat, 21 May 2022 11:49:47 +0200
Morten Brørup <mb@smartsharesystems.com> wrote:

> > 
> > Also, worth considering dropping DPDK random number generator
> > in userspace for security reasons and just using more secure kernel
> > code.  
> 
> Absolutely not! We need a fast pseudorandom number generator in DPDK.
> 
> If anything, we could consider renaming the functions and header file to reflect that they are pseudorandom number generators, and not (cryptographically) random generators. That would cause an API/ABI breakage, so it's probably not going to happen. ;-)


The Linux kernel has received an way more attention on random numbers than
DPDK. If you follow the history, what happens is that a simple dumb LCG
or similar random number generator gets invented, and then gets used for
lots of things that people don't think need a strong generator.

Followed by DoS and other attacks where the weak random number generator
is broken when used for doing things like creating sequence numbers of
TCP port assignment.  This is then followed by even more work on the
kernel random number generator to make the default random number generator
stronger.

I bring up this history, so that DPDK won't have to repeat it.

Right now the DPDK random number generator is insecure because it uses
long but weak PRNG and never reseeds itself.

See:
https://lwn.net/Articles/884875/

There is also FIPS to consider.
https://lwn.net/Articles/877607/

Since random number generators are hard, prefer that someone else do it :-)