Allow the use of the iPXE DRBG implementation in BSD-licensed
projects.
Requested-by: Sean Davis <dive@hq.endersgame.net>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[rng] Add ANS X9.82 Approved Hash_df derivation function
ANS X9.82 specifies several Approved derivation functions for use in
distributing entropy throughout a buffer. One such derivation
function is Hash_df, which can be implemented using the existing iPXE
SHA-1 functionality.
Signed-off-by: Michael Brown <mcb30@ipxe.org>