Hook keywrap source code into Kconfig and Makefile
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Setkey function has been split into set_priv_key and set_pub_key.
Akcipher requests takes sgl for src and dst instead of void *.
Users of the API i.e. two existing RSA implementation and
test mgr code have been updated accordingly.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch introduces the crypto skcipher interface which aims
to replace both blkcipher and ablkcipher.
It's very similar to the existing ablkcipher interface. The
main difference is the removal of the givcrypt interface. In
order to make the transition easier for blkcipher users, there
is a helper SKCIPHER_REQUEST_ON_STACK which can be used to place
a request on the stack for synchronous transforms.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The Kconfig option NULL2 has been added as CRYPTO_MANAGER now
depends indirectly on NULL2. However, the Makefile was not updated
to use the new option, resulting in potential build failures when
only NULL2 is enabled.
Fixes: 149a39717d ("crypto: aead - Add type-safe geniv init/exit helpers")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The core of the Jitter RNG is intended to be compiled with -O0. To
ensure that the Jitter RNG can be compiled on all architectures,
separate out the RNG core into a stand-alone C file that can be compiled
with -O0 which does not depend on any kernel include file.
As no kernel includes can be used in the C file implementing the core
RNG, any dependencies on kernel code must be extracted.
A second file provides the link to the kernel and the kernel crypto API
that can be compiled with the regular compile options of the kernel.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add a new rsa generic SW implementation.
This implements only cryptographic primitives.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Added select on ASN1.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add Public Key Encryption API.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Made CRYPTO_AKCIPHER invisible like other type config options.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Replace the global -O0 compiler flag from the Makefile with GCC
pragmas to mark only the functions required to be compiled without
optimizations.
This patch also adds a comment describing the rationale for the
functions chosen to be compiled without optimizations.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This AEAD uses a chacha20 ablkcipher and a poly1305 ahash to construct the
ChaCha20-Poly1305 AEAD as defined in RFC7539. It supports both synchronous and
asynchronous operations, even if we currently have no async chacha20 or poly1305
drivers.
Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Poly1305 is a fast message authenticator designed by Daniel J. Bernstein.
It is further defined in RFC7539 as a building block for the ChaCha20-Poly1305
AEAD for use in IETF protocols.
This is a portable C implementation of the algorithm without architecture
specific optimizations, based on public domain code by Daniel J. Bernstein and
Andrew Moon.
Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ChaCha20 is a high speed 256-bit key size stream cipher algorithm designed by
Daniel J. Bernstein. It is further specified in RFC7539 for use in IETF
protocols as a building block for the ChaCha20-Poly1305 AEAD.
This is a portable C implementation without any architecture specific
optimizations. It uses a 16-byte IV, which includes the 12-byte ChaCha20 nonce
prepended by the initial block counter. Some algorithms require an explicit
counter value, for example the mentioned AEAD construction.
Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The CPU Jitter RNG provides a source of good entropy by
collecting CPU executing time jitter. The entropy in the CPU
execution time jitter is magnified by the CPU Jitter Random
Number Generator. The CPU Jitter Random Number Generator uses
the CPU execution timing jitter to generate a bit stream
which complies with different statistical measurements that
determine the bit stream is random.
The CPU Jitter Random Number Generator delivers entropy which
follows information theoretical requirements. Based on these
studies and the implementation, the caller can assume that
one bit of data extracted from the CPU Jitter Random Number
Generator holds one bit of entropy.
The CPU Jitter Random Number Generator provides a decentralized
source of entropy, i.e. every caller can operate on a private
state of the entropy pool.
The RNG does not have any dependencies on any other service
in the kernel. The RNG only needs a high-resolution time
stamp.
Further design details, the cryptographic assessment and
large array of test results are documented at
http://www.chronox.de/jent.html.
CC: Andreas Steffen <andreas.steffen@strongswan.org>
CC: Theodore Ts'o <tytso@mit.edu>
CC: Sandy Harris <sandyinchina@gmail.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a new AEAD IV generator echainiv. It is intended
to replace the existing skcipher IV generator eseqiv.
If the underlying AEAD algorithm is using the old AEAD interface,
then echainiv will simply use its IV generator.
Otherwise, echainiv will encrypt a counter just like eseqiv but
it'll first xor it against a previously stored IV similar to
chainiv.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Enable compilation of the AEAD AF_ALG support and provide a Kconfig
option to compile the AEAD AF_ALG support.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Enable compilation of the RNG AF_ALG support and provide a Kconfig
option to compile the RNG AF_ALG support.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch introduces the multi-buffer crypto daemon which is responsible
for submitting crypto jobs in a work queue to the responsible multi-buffer
crypto algorithm. The idea of the multi-buffer algorihtm is to put
data streams from multiple jobs in a wide (AVX2) register and then
take advantage of SIMD instructions to do crypto computation on several
buffers simultaneously.
The multi-buffer crypto daemon is also responsbile for flushing the
remaining buffers to complete the computation if no new buffers arrive
for a while.
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch removes the build-time test that ensures at least one RNG
is set. Instead we will simply not build drbg if no options are set
through Kconfig.
This also fixes a typo in the name of the Kconfig option CRYTPO_DRBG
(should be CRYPTO_DRBG).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We added the soft module dependency of crc32c module alias
to generic crc32c module so other hardware accelerated crc32c
modules could get loaded and used before the generic version.
We also renamed the crypto/crc32c.c containing the generic
crc32c crypto computation to crypto/crc32c_generic.c according
to convention.
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Disabling compiler optimizations can be fragile, since a new
optimization could be added to -O0 or -Os that breaks the assumptions
the code is making.
Instead of disabling compiler optimizations, use a dummy inline assembly
(based on RELOC_HIDE) to block the problematic kinds of optimization,
while still allowing other optimizations to be applied to the code.
The dummy inline assembly is added after every OR, and has the
accumulator variable as its input and output. The compiler is forced to
assume that the dummy inline assembly could both depend on the
accumulator variable and change the accumulator variable, so it is
forced to compute the value correctly before the inline assembly, and
cannot assume anything about its value after the inline assembly.
This change should be enough to make crypto_memneq work correctly (with
data-independent timing) even if it is inlined at its call sites. That
can be done later in a followup patch.
Compile-tested on x86_64.
Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.eti.br>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull crypto update from Herbert Xu:
- Made x86 ablk_helper generic for ARM
- Phase out chainiv in favour of eseqiv (affects IPsec)
- Fixed aes-cbc IV corruption on s390
- Added constant-time crypto_memneq which replaces memcmp
- Fixed aes-ctr in omap-aes
- Added OMAP3 ROM RNG support
- Add PRNG support for MSM SoC's
- Add and use Job Ring API in caam
- Misc fixes
[ NOTE! This pull request was sent within the merge window, but Herbert
has some questionable email sending setup that makes him public enemy
#1 as far as gmail is concerned. So most of his emails seem to be
trapped by gmail as spam, resulting in me not seeing them. - Linus ]
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (49 commits)
crypto: s390 - Fix aes-cbc IV corruption
crypto: omap-aes - Fix CTR mode counter length
crypto: omap-sham - Add missing modalias
padata: make the sequence counter an atomic_t
crypto: caam - Modify the interface layers to use JR API's
crypto: caam - Add API's to allocate/free Job Rings
crypto: caam - Add Platform driver for Job Ring
hwrng: msm - Add PRNG support for MSM SoC's
ARM: DT: msm: Add Qualcomm's PRNG driver binding document
crypto: skcipher - Use eseqiv even on UP machines
crypto: talitos - Simplify key parsing
crypto: picoxcell - Simplify and harden key parsing
crypto: ixp4xx - Simplify and harden key parsing
crypto: authencesn - Simplify key parsing
crypto: authenc - Export key parsing helper function
crypto: mv_cesa: remove deprecated IRQF_DISABLED
hwrng: OMAP3 ROM Random Number Generator support
crypto: sha256_ssse3 - also test for BMI2
crypto: mv_cesa - Remove redundant of_match_ptr
crypto: sahara - Remove redundant of_match_ptr
...
This patch provides a single place for information about hash algorithms,
such as hash sizes and kernel driver names, which will be used by IMA
and the public key code.
Changelog:
- Fix sparse and checkpatch warnings
- Move hash algo enums to uapi for userspace signing functions.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
When comparing MAC hashes, AEAD authentication tags, or other hash
values in the context of authentication or integrity checking, it
is important not to leak timing information to a potential attacker,
i.e. when communication happens over a network.
Bytewise memory comparisons (such as memcmp) are usually optimized so
that they return a nonzero value as soon as a mismatch is found. E.g,
on x86_64/i5 for 512 bytes this can be ~50 cyc for a full mismatch
and up to ~850 cyc for a full match (cold). This early-return behavior
can leak timing information as a side channel, allowing an attacker to
iteratively guess the correct result.
This patch adds a new method crypto_memneq ("memory not equal to each
other") to the crypto API that compares memory areas of the same length
in roughly "constant time" (cache misses could change the timing, but
since they don't reveal information about the content of the strings
being compared, they are effectively benign). Iow, best and worst case
behaviour take the same amount of time to complete (in contrast to
memcmp).
Note that crypto_memneq (unlike memcmp) can only be used to test for
equality or inequality, NOT for lexicographical order. This, however,
is not an issue for its use-cases within the crypto API.
We tried to locate all of the places in the crypto API where memcmp was
being used for authentication or integrity checking, and convert them
over to crypto_memneq.
crypto_memneq is declared noinline, placed in its own source file,
and compiled with optimizations that might increase code size disabled
("Os") because a smart compiler (or LTO) might notice that the return
value is always compared against zero/nonzero, and might then
reintroduce the same early-return optimization that we are trying to
avoid.
Using #pragma or __attribute__ optimization annotations of the code
for disabling optimization was avoided as it seems to be considered
broken or unmaintained for long time in GCC [1]. Therefore, we work
around that by specifying the compile flag for memneq.o directly in
the Makefile. We found that this seems to be most appropriate.
As we use ("Os"), this patch also provides a loop-free "fast-path" for
frequently used 16 byte digests. Similarly to kernel library string
functions, leave an option for future even further optimized architecture
specific assembler implementations.
This was a joint work of James Yonan and Daniel Borkmann. Also thanks
for feedback from Florian Weimer on this and earlier proposals [2].
[1] http://gcc.gnu.org/ml/gcc/2012-07/msg00211.html
[2] https://lkml.org/lkml/2013/2/10/131
Signed-off-by: James Yonan <james@openvpn.net>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Create a generic version of ablk_helper so it can be reused
by other architectures.
Acked-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Unfortunately, even with a softdep some distros fail to include
the necessary modules in the initrd. Therefore this patch adds
a fallback path to restore existing behaviour where we cannot
load the new crypto crct10dif algorithm.
In order to do this, the underlying crct10dif has been split out
from the crypto implementation so that it can be used on the
fallback path.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch reinstates commits
67822649d739761214ee0b95a7f85731d939625a2d31e518a4
Now that module softdeps are in the kernel we can use that to resolve
the boot issue which cause the revert.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull crypto fixes from Herbert Xu:
"This push fixes a memory corruption issue in caam, as well as
reverting the new optimised crct10dif implementation as it breaks boot
on initrd systems.
Hopefully crct10dif will be reinstated once the supporting code is
added so that it doesn't break boot"
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
Revert "crypto: crct10dif - Wrap crc_t10dif function all to use crypto transform framework"
crypto: caam - Fixed the memory out of bound overwrite issue
This reverts commits
67822649d739761214ee0b95a7f85731d939625a2d31e518a4
Unfortunately this change broke boot on some systems that used an
initrd which does not include the newly created crct10dif modules.
As these modules are required by sd_mod under certain configurations
this is a serious problem.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add support for lz4 and lz4hc compression algorithm using the lib/lz4/*
codebase.
[akpm@linux-foundation.org: fix warnings]
Signed-off-by: Chanho Min <chanho.min@lge.com>
Cc: "Darrick J. Wong" <djwong@us.ibm.com>
Cc: Bob Pearson <rpearson@systemfabricworks.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Herbert Xu <herbert@gondor.hengli.com.au>
Cc: Yann Collet <yann.collet.73@gmail.com>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When CRC T10 DIF is calculated using the crypto transform framework, we
wrap the crc_t10dif function call to utilize it. This allows us to
take advantage of any accelerated CRC T10 DIF transform that is
plugged into the crypto framework.
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Patch adds support for NIST recommended block cipher mode CMAC to CryptoAPI.
This work is based on Tom St Denis' earlier patch,
http://marc.info/?l=linux-crypto-vger&m=135877306305466&w=2
Cc: Tom St Denis <tstdenis@elliptictech.com>
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds crc32 algorithms to shash crypto api. One is wrapper to
gerneric crc32_le function. Second is crc32 pclmulqdq implementation. It
use hardware provided PCLMULQDQ instruction to accelerate the CRC32 disposal.
This instruction present from Intel Westmere and AMD Bulldozer CPUs.
For intel core i5 I got 450MB/s for table implementation and 2100MB/s
for pclmulqdq implementation.
Signed-off-by: Alexander Boyko <alexander_boyko@xyratex.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
CAST5 and CAST6 both use same lookup tables, which can be moved shared module
'cast_common'.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull module signing support from Rusty Russell:
"module signing is the highlight, but it's an all-over David Howells frenzy..."
Hmm "Magrathea: Glacier signing key". Somebody has been reading too much HHGTTG.
* 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (37 commits)
X.509: Fix indefinite length element skip error handling
X.509: Convert some printk calls to pr_devel
asymmetric keys: fix printk format warning
MODSIGN: Fix 32-bit overflow in X.509 certificate validity date checking
MODSIGN: Make mrproper should remove generated files.
MODSIGN: Use utf8 strings in signer's name in autogenerated X.509 certs
MODSIGN: Use the same digest for the autogen key sig as for the module sig
MODSIGN: Sign modules during the build process
MODSIGN: Provide a script for generating a key ID from an X.509 cert
MODSIGN: Implement module signature checking
MODSIGN: Provide module signing public keys to the kernel
MODSIGN: Automatically generate module signing keys if missing
MODSIGN: Provide Kconfig options
MODSIGN: Provide gitignore and make clean rules for extra files
MODSIGN: Add FIPS policy
module: signature checking hook
X.509: Add a crypto key parser for binary (DER) X.509 certificates
MPILIB: Provide a function to read raw data into an MPI
X.509: Add an ASN.1 decoder
X.509: Add simple ASN.1 grammar compiler
...
Create a key type that can be used to represent an asymmetric key type for use
in appropriate cryptographic operations, such as encryption, decryption,
signature generation and signature verification.
The key type is "asymmetric" and can provide access to a variety of
cryptographic algorithms.
Possibly, this would be better as "public_key" - but that has the disadvantage
that "public key" is an overloaded term.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This patch add the 842 cryptographic API driver that
submits compression requests to the 842 hardware compression
accelerator driver (nx-compress).
If the hardware accelerator goes offline for any reason
(dynamic disable, migration, etc...), this driver will use LZO
as a software failover for all future compression requests.
For decompression requests, the 842 hardware driver contains
a software implementation of the 842 decompressor to support
the decompression of data that was compressed before the accelerator
went offline.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rename cast6 module to cast6_generic to allow autoloading of optimized
implementations. Generic functions and s-boxes are exported to be able to use
them within optimized implementations.
Signed-off-by: Johannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rename cast5 module to cast5_generic to allow autoloading of optimized
implementations. Generic functions and s-boxes are exported to be able to use
them within optimized implementations.
Signed-off-by: Johannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rename camellia module to camellia_generic to allow optimized assembler
implementations to autoload with module-alias.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Now that serpent.c has been cleaned from checkpatch warnings,
we can do clean rename.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rename module from serpent.ko to serpent_generic.ko and add module alias. This
is to allow assembler implementation to autoload on 'modprobe serpent'. Also
add driver_name and priority for serpent cipher.
CC: Dag Arne Osvik <osvik@ii.uib.no>
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a basic userspace configuration API for the crypto layer.
With this it is possible to instantiate, remove and to show crypto
algorithms from userspace.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rename blowfish to blowfish_generic so that assembler versions of blowfish
cipher can autoload. Module alias 'blowfish' is added.
Also fix checkpatch warnings.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Patch splits up the blowfish crypto routine into a common part (key setup)
which will be used by blowfish crypto modules (x86_64 assembly and generic-c).
Also fixes errors/warnings reported by checkpatch.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ESP with separate encryption/authentication algorithms needs a special
treatment for the associated data. This patch add a new algorithm that
handles esp with extended sequence numbers.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changed Makefile to use <modules>-y instead of <modules>-objs.
Signed-off-by: Tracey Dent <tdent48227@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the af_alg plugin for symmetric key ciphers,
corresponding to the ablkcipher kernel operation type.
Keys can optionally be set through the setsockopt interface.
Once a sendmsg call occurs without MSG_MORE no further writes
may be made to the socket until all previous data has been read.
IVs and and whether encryption/decryption is performed can be
set through the setsockopt interface or as a control message
to sendmsg.
The interface is completely synchronous, all operations are
carried out in recvmsg(2) and will complete prior to the system
call returning.
The splice(2) interface support reading the user-space data directly
without copying (except that the Crypto API itself may copy the data
if alignment is off).
The recvmsg(2) interface supports directly writing to user-space
without additional copying, i.e., the kernel crypto interface will
receive the user-space address as its output SG list.
Thakns to Miloslav Trmac for reviewing this and contributing
fixes and improvements.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: David S. Miller <davem@davemloft.net>
This patch adds the af_alg plugin for hash, corresponding to
the ahash kernel operation type.
Keys can optionally be set through the setsockopt interface.
Each sendmsg call will finalise the hash unless sent with a MSG_MORE
flag.
Partial hash states can be cloned using accept(2).
The interface is completely synchronous, all operations will
complete prior to the system call returning.
Both sendmsg(2) and splice(2) support reading the user-space
data directly without copying (except that the Crypto API itself
may copy the data if alignment is off).
For now only the splice(2) interface supports performing digest
instead of init/update/final. In future the sendmsg(2) interface
will also be modified to use digest/finup where possible so that
hardware that cannot return a partial hash state can still benefit
from this interface.
Thakns to Miloslav Trmac for reviewing this and contributing
fixes and improvements.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Martin Willi <martin@strongswan.org>
