sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

cryptosoft: Fully support per-operation keys for auth algorithms.

Only pre-allocate auth contexts when a session-wide key is provided or
for sessions without keys. For sessions with per-operation keys,
always initialize the on-stack context directly rather than
initializing the session context in swcr_authprepare (now removed) and
then copying that session context into the on-stack context.

This approach permits parallel auth operations without needing a
serializing lock. In addition, the previous code assumed that auth
sessions always provided an initial key unlike cipher sessions which
assume either an initial key or per-op keys.

While here, fix the Blake2 auth transforms to function like other auth
transforms where Setkey is invoked after Init rather than before.

Reviewed by: markj
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33316

crypto: Constify all transform descriptors

No functional change intended.

Reviewed by: ae, jhb
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D31196

Adjust crypto_apply function callbacks for OCF.

- crypto_apply() is only used for reading a buffer to compute a
digest, so change the data pointer to a const pointer.

- To better match m_apply(), change the data pointer type to void *
and the length from uint16_t to u_int. The length field in
particular matters as none of the apply logic was splitting requests
larger than UINT16_MAX.

- Adjust the auth_xform Update callback to match the function
prototype passed to crypto_apply() and crypto_apply_buf(). This
removes the needs for casts when using the Update callback.

- Change the Reinit and Setkey callbacks to also use a u_int length
instead of uint16_t.

- Update auth transforms for the changes. While here, use C99
initializers for auth_hash structures and avoid casts on callbacks.

Reviewed by: cem
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D25171

Import Blake2 algorithms (blake2b, blake2s) from libb2

The upstream repository is on github BLAKE2/libb2. Files landed in
sys/contrib/libb2 are the unmodified upstream files, except for one
difference: secure_zero_memory's contents have been replaced with
explicit_bzero() only because the previous implementation broke powerpc
link. Preferential use of explicit_bzero() is in progress upstream, so
it is anticipated we will be able to drop this diff in the future.

sys/crypto/blake2 contains the source files needed to port libb2 to our
build system, a wrapped (limited) variant of the algorithm to match the API
of our auth_transform softcrypto abstraction, incorporation into the Open
Crypto Framework (OCF) cryptosoft(4) driver, as well as an x86 SSE/AVX
accelerated OCF driver, blake2(4).

Optimized variants of blake2 are compiled for a number of x86 machines
(anything from SSE2 to AVX + XOP). On those machines, FPU context will need
to be explicitly saved before using blake2(4)-provided algorithms directly.
Use via cryptodev / OCF saves FPU state automatically, and use via the
auth_transform softcrypto abstraction does not use FPU.

The intent of the OCF driver is mostly to enable testing in userspace via
/dev/crypto. ATF tests are added with published KAT test vectors to
validate correctness.

Reviewed by: jhb, markj
Obtained from: github BLAKE2/libb2
Differential Revision: https://reviews.freebsd.org/D14662