Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Overhaul driver/subsystem api's:
o make all crypto drivers have a device_t; pseudo drivers like the s/w
crypto driver synthesize one
o change the api between the crypto subsystem and drivers to use kobj;
cryptodev_if.m defines this api
o use the fact that all crypto drivers now have a device_t to add support
for specifying which of several potential devices to use when doing
crypto operations
o add new ioctls that allow user apps to select a specific crypto device
to use (previous ioctls maintained for compatibility)
o overhaul crypto subsystem code to eliminate lots of cruft and hide
implementation details from drivers
o bring in numerous fixes from Michale Richardson/hifn; mostly for
795x parts
o add an optional mechanism for mmap'ing the hifn 795x public key h/w
to user space for use by openssl (not enabled by default)
o update crypto test tools to use new ioctl's and add cmd line options
to specify a device to use for tests

These changes will also enable much future work on improving the core
crypto subsystem; including proper load balancing and interposing code
between the core and drivers to dispatch small operations to the s/w
driver as appropriate.

These changes were instigated by the work of Michael Richardson.

Reviewed by: pjd
Approved by: re

- Fix a very old bug in HMAC/SHA{384,512}. When HMAC is using SHA384
or SHA512, the blocksize is 128 bytes, not 64 bytes as anywhere else.
The bug also exists in NetBSD, OpenBSD and various other independed
implementations I look at.
- We cannot decide which hash function to use for HMAC based on the key
length, because any HMAC function can use any key length.
To fix it split CRYPTO_SHA2_HMAC into three algorithm:
CRYPTO_SHA2_256_HMAC, CRYPTO_SHA2_384_HMAC and CRYPTO_SHA2_512_HMAC.
Those names are consistent with OpenBSD's naming.
- Remove authsize field from auth_hash structure.
- Allow consumer to define size of hash he wants to receive.
This allows to use HMAC not only for IPsec, where 96 bits MAC is requested.
The size of requested MAC is defined at newsession time in the cri_mlen
field - when 0, entire MAC will be returned.
- Add swcr_authprepare() function which prepares authentication key.
- Allow to provide key for every authentication operation, not only at
newsession time by honoring CRD_F_KEY_EXPLICIT flag.
- Make giving key at newsession time optional - don't try to operate on it
if its NULL.
- Extend COPYBACK()/COPYDATA() macros to handle CRYPTO_BUF_CONTIG buffer
type as well.
- Accept CRYPTO_BUF_IOV buffer type in swcr_authcompute() as we have
cuio_apply() now.
- 16 bits for key length (SW_klen) is more than enough.

Reviewed by: sam

/* -> /*- for license, minor formatting changes

In-kernel crypto framework derived from openbsd. This facility provides
a consistent interface to h/w and s/w crypto algorithms for use by the
kernel and (for h/w at least) by user-mode apps. Access for user-level
code is through a /dev/crypto device that'll eventually be used by openssl
to (potentially) accelerate many applications. Coming soon is an IPsec
that makes use of this service to accelerate ESP, AH, and IPCOMP protocols.

Included here is the "core" crypto support, /dev/crypto driver, various
crypto algorithms that are not already present in the KAME crypto area,
and support routines used by crypto device drivers.

Obtained from: openbsd