This patch converts the low-level crypto_rng interface to the
"new" style.

This allows existing implementations to be converted over one-
by-one.  Once that is complete we can then remove the old rng
interface.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

There is no reason why crypto_rng_reset should modify the seed
so this patch marks it as const.  Since our algorithms don't
export a const seed function yet we have to go through some
contortions for now.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch adds the new top-level function crypto_rng_generate
which generates random numbers with additional input.  It also
extends the mid-level rng_gen_random function to take additional
data as input.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch converts the top-level crypto_rng to the "new" style.
It was the last algorithm type added before we switched over
to the new way of doing things exemplified by shash.

All users will automatically switch over to the new interface.

Note that this patch does not touch the low-level interface to
rng implementations.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Change the RNGs to always return 0 in success case.

This patch ensures that seqiv.c works with RNGs other than krng. seqiv
expects that any return code other than 0 is an error. Without the
patch, rfc4106(gcm(aes)) will not work when using a DRBG or an ANSI
X9.31 RNG.
Signed-off-by: NStephan Mueller <smueller@chronox.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

The API function calls exported by the kernel crypto API for RNGs to
be used by consumers are documented.
Signed-off-by: NStephan Mueller <smueller@chronox.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch adds a random number generator interface as well as a
cryptographic pseudo-random number generator based on AES.  It is
meant to be used in cases where a deterministic CPRNG is required.

One of the first applications will be as an input in the IPsec IV
generation process.
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>