[rng] Add ANS X9.82 Approved Source of Entropy Input
ANS X9.82 specifies several Approved Sources of Entropy Input (SEI).
One such SEI uses an entropy source as the Source of Entropy Input,
condensing each entropy source output after each GetEntropy call.
This can be implemented relatively cheaply in iPXE and avoids the need
to allocate potentially very large buffers.
(Note that the terms "entropy source" and "Source of Entropy Input"
are not synonyms within the context of ANS X9.82.)
Use the iPXE API mechanism to allow entropy sources to be selected at
compilation time.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
ANS X9.82 specifies several Approved algorithms for use in a
Deterministic Random Bit Generator (DRBG). One such algorithm is
HMAC_DRBG, which can be implemented using the existing iPXE SHA-1 and
HMAC functionality. This algorithm provides a maximum security
strength of 128 bits.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown