crypto: api - Disallow identical driver names

Disallow registration of two algorithms with identical driver names.

Cc: <stable@vger.kernel.org>
Reported-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Use work queue in crypto_destroy_instance

The function crypto_drop_spawn expects to be called in process
context. However, when an instance is unregistered while it still
has active users, the last user may cause the instance to be freed
in atomic context.

Fix this by delaying the freeing to a work queue.

Fixes: 6bfd48096ff8 ("[CRYPTO] api: Added spawns")
Reported-by: Florent Revest <revest@chromium.org>
Reported-by: syzbot+d769eed29cc42d75e2a3@syzkaller.appspotmail.com
Reported-by: syzbot+610ec0671f51e838436e@syzkaller.appspotmail.com
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Florent Revest <revest@chromium.org>
Acked-by: Florent Revest <revest@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: engine - fix crypto_queue backlog handling

CRYPTO_TFM_REQ_MAY_BACKLOG tells the crypto driver that it should
internally backlog requests until the crypto hw's queue becomes
full. At that point, crypto_engine backlogs the request and returns
-EBUSY. Calling driver such as dm-crypt then waits until the
complete() function is called with a status of -EINPROGRESS before
sending a new request.

The problem lies in the call to complete() with a value of -EINPROGRESS
that is made when a backlog item is present on the queue. The call is
done before the successful execution of the crypto request. In the case
that do_one_request() returns < 0 and the retry support is available,
the request is put back in the queue. This leads upper drivers to send
a new request even if the queue is still full.

The problem can be reproduced by doing a large dd into a crypto
dm-crypt device. This is pretty easy to see when using
Freescale CAAM crypto driver and SWIOTLB dma. Since the actual amount
of requests that can be hold in the queue is unlimited we get IOs error
and dma allocation.

The fix is to call complete with a value of -EINPROGRESS only if
the request is not enqueued back in crypto_queue. This is done
by calling complete() later in the code. In order to delay the decision,
crypto_queue is modified to correctly set the backlog pointer
when a request is enqueued back.

Fixes: 6a89f492f8e5 ("crypto: engine - support for parallel requests based on retry mechanism")
Co-developed-by: Sylvain Ouellet <souellet@genetec.com>
Signed-off-by: Sylvain Ouellet <souellet@genetec.com>
Signed-off-by: Olivier Bacon <obacon@genetec.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Demote BUG_ON() in crypto_unregister_alg() to a WARN_ON()

The crypto_unregister_alg() function expects callers to ensure that any
algorithm that is unregistered has a refcnt of exactly 1, and issues a
BUG_ON() if this is not the case. However, there are in fact drivers that
will call crypto_unregister_alg() without ensuring that the refcnt has been
lowered first, most notably on system shutdown. This causes the BUG_ON() to
trigger, which prevents a clean shutdown and hangs the system.

To avoid such hangs on shutdown, demote the BUG_ON() in
crypto_unregister_alg() to a WARN_ON() with early return. Cc stable because
this problem was observed on a 6.2 kernel, cf the link below.

Link: https://lore.kernel.org/r/87r0tyq8ph.fsf@toke.dk
Cc: stable@vger.kernel.org
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: rng - Count error stats differently

Move all stat code specific to rng into the rng code.

While we're at it, change the stats so that bytes and counts
are always incremented even in case of error. This allows the
reference counting to be removed as we can now increment the
counters prior to the operation.

After the operation we simply increase the error count if necessary.
This is safe as errors can only occur synchronously (or rather,
the existing code already ignored asynchronous errors which are
only visible to the callback function).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: skcipher - Count error stats differently

Move all stat code specific to skcipher into the skcipher code.

While we're at it, change the stats so that bytes and counts
are always incremented even in case of error. This allows the
reference counting to be removed as we can now increment the
counters prior to the operation.

After the operation we simply increase the error count if necessary.
This is safe as errors can only occur synchronously (or rather,
the existing code already ignored asynchronous errors which are
only visible to the callback function).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: kpp - Count error stats differently

Move all stat code specific to kpp into the kpp code.

While we're at it, change the stats so that bytes and counts
are always incremented even in case of error. This allows the
reference counting to be removed as we can now increment the
counters prior to the operation.

After the operation we simply increase the error count if necessary.
This is safe as errors can only occur synchronously (or rather,
the existing code already ignored asynchronous errors which are
only visible to the callback function).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: acomp - Count error stats differently

Move all stat code specific to acomp into the acomp code.

While we're at it, change the stats so that bytes and counts
are always incremented even in case of error. This allows the
reference counting to be removed as we can now increment the
counters prior to the operation.

After the operation we simply increase the error count if necessary.
This is safe as errors can only occur synchronously (or rather,
the existing code already ignored asynchronous errors which are
only visible to the callback function).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: hash - Count error stats differently

Move all stat code specific to hash into the hash code.

While we're at it, change the stats so that bytes and counts
are always incremented even in case of error. This allows the
reference counting to be removed as we can now increment the
counters prior to the operation.

After the operation we simply increase the error count if necessary.
This is safe as errors can only occur synchronously (or rather,
the existing code already ignored asynchronous errors which are
only visible to the callback function).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: akcipher - Count error stats differently

Move all stat code specific to akcipher into the akcipher code.

While we're at it, change the stats so that bytes and counts
are always incremented even in case of error. This allows the
reference counting to be removed as we can now increment the
counters prior to the operation.

After the operation we simply increase the error count if necessary.
This is safe as errors can only occur synchronously (or rather,
the existing code already ignored asynchronous errors which are
only visible to the callback function).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: aead - Count error stats differently

Move all stat code specific to aead into the aead code.

While we're at it, change the stats so that bytes and counts
are always incremented even in case of error. This allows the
reference counting to be removed as we can now increment the
counters prior to the operation.

After the operation we simply increase the error count if necessary.
This is safe as errors can only occur synchronously (or rather,
the existing code already ignored asynchronous errors which are
only visible to the callback function).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - compile out crypto_boot_test_finished when tests disabled

The crypto_boot_test_finished static key is unnecessary when self-tests
are disabled in the kconfig, so optimize it out accordingly, along with
the entirety of crypto_start_tests(). This mainly avoids the overhead
of an unnecessary static_branch_enable() on every boot.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algboss - optimize registration of internal algorithms

Since algboss always skips testing of algorithms with the
CRYPTO_ALG_INTERNAL flag, there is no need to go through the dance of
creating the test kthread, which creates a lot of overhead. Instead, we
can just directly finish the algorithm registration, like is now done
when self-tests are disabled entirely.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - optimize algorithm registration when self-tests disabled

Currently, registering an algorithm with the crypto API always causes a
notification to be posted to the "cryptomgr", which then creates a
kthread to self-test the algorithm. However, if self-tests are disabled
in the kconfig (as is the default option), then this kthread just
notifies waiters that the algorithm has been tested, then exits.

This causes a significant amount of overhead, especially in the kthread
creation and destruction, which is not necessary at all. For example,
in a quick test I found that booting a "minimum" x86_64 kernel with all
the crypto options enabled (except for the self-tests) takes about 400ms
until PID 1 can start. Of that, a full 13ms is spent just doing this
pointless dance, involving a kthread being created, run, and destroyed
over 200 times. That's over 3% of the entire kernel start time.

Fix this by just skipping the creation of the test larval and the
posting of the registration notification entirely, when self-tests are
disabled.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: lib - move __crypto_xor into utils

CRYPTO_LIB_CHACHA depends on CRYPTO for __crypto_xor, defined in
crypto/algapi.c. This is a layering violation because the dependencies
should only go in the other direction (crypto/ => lib/crypto/). Also
the correct dependency would be CRYPTO_ALGAPI, not CRYPTO. Fix this by
moving __crypto_xor into the utils module in lib/crypto/.

Note that CRYPTO_LIB_CHACHA_GENERIC selected XOR_BLOCKS, which is
unrelated and unnecessary. It was perhaps thought that XOR_BLOCKS was
needed for __crypto_xor, but that's not the case.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: crypto_xor - use helpers for unaligned accesses

Dereferencing a misaligned pointer is undefined behavior in C, and may
result in codegen on architectures such as ARM that trigger alignments
traps and expensive fixups in software.

Instead, use the get_aligned()/put_aligned() accessors, which are cheap
or even completely free when CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y.

In the converse case, the prior alignment checks ensure that the casts
are safe, and so no unaligned accessors are necessary.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - allow algs only in specific constructions in FIPS mode

Currently we do not distinguish between algorithms that fail on
the self-test vs. those which are disabled in FIPS mode (not allowed).
Both are marked as having failed the self-test.

Recently the need arose to allow the usage of certain algorithms only
as arguments to specific template instantiations in FIPS mode. For
example, standalone "dh" must be blocked, but e.g. "ffdhe2048(dh)" is
allowed. Other potential use cases include "cbcmac(aes)", which must
only be used with ccm(), or "ghash", which must be used only for
gcm().

This patch allows this scenario by adding a new flag FIPS_INTERNAL to
indicate those algorithms that are not FIPS-allowed. They can then be
used as template arguments only, i.e. when looked up via
crypto_grab_spawn() to be more specific. The FIPS_INTERNAL bit gets
propagated upwards recursively into the surrounding template
instances, until the construction eventually matches an explicit
testmgr entry with ->fips_allowed being set, if any.

The behaviour to skip !->fips_allowed self-test executions in FIPS
mode will be retained. Note that this effectively means that
FIPS_INTERNAL algorithms are handled very similarly to the INTERNAL
ones in this regard. It is expected that the FIPS_INTERNAL algorithms
will receive sufficient testing when the larger constructions they're
a part of, if any, get exercised by testmgr.

Note that as a side-effect of this patch algorithms which are not
FIPS-allowed will now return ENOENT instead of ELIBBAD. Hopefully
this is not an issue as some people were relying on this already.

Link: https://lore.kernel.org/r/YeEVSaMEVJb3cQkq@gondor.apana.org.au
Originally-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Nicolai Stange <nstange@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: testmgr - Move crypto_simd_disabled_for_test out

As testmgr is part of cryptomgr which was designed to be unloadable
as a module, it shouldn't export any symbols for other crypto
modules to use as that would prevent it from being unloaded. All
its functionality is meant to be accessed through notifiers.

The symbol crypto_simd_disabled_for_test was added to testmgr
which caused it to be pinned as a module if its users were also
loaded. This patch moves it out of testmgr and into crypto/algapi.c
so cryptomgr can again be unloaded and replaced on demand.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Move cryptomgr soft dependency into algapi

The soft dependency on cryptomgr is only needed in algapi because
if algapi isn't present then no algorithms can be loaded. This
also fixes the case where api is built-in but algapi is built as
a module as the soft dependency would otherwise get lost.

Fixes: 8ab23d547f65 ("crypto: api - Add softdep on cryptomgr")
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Fix boot-up crash when crypto manager is disabled

When the crypto manager is disabled, we need to explicitly set
the crypto algorithms' tested status so that they can be used.

Fixes: cad439fc040e ("crypto: api - Do not create test larvals if...")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: Ido Schimmel <idosch@idosch.org>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Do not create test larvals if manager is disabled

The delayed boot-time testing patch created a dependency loop
between api.c and algapi.c because it added a crypto_alg_tested
call to the former when the crypto manager is disabled.

We could instead avoid creating the test larvals if the crypto
manager is disabled. This avoids the dependency loop as well
as saving some unnecessary work, albeit in a very unlikely case.

Reported-by: Nathan Chancellor <nathan@kernel.org>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: kernel test robot <lkp@intel.com>
Fixes: adad556efcdd ("crypto: api - Fix built-in testing dependency failures")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Fix built-in testing dependency failures

When complex algorithms that depend on other algorithms are built
into the kernel, the order of registration must be done such that
the underlying algorithms are ready before the ones on top are
registered. As otherwise they would fail during the self-test
which is required during registration.

In the past we have used subsystem initialisation ordering to
guarantee this. The number of such precedence levels are limited
and they may cause ripple effects in other subsystems.

This patch solves this problem by delaying all self-tests during
boot-up for built-in algorithms. They will be tested either when
something else in the kernel requests for them, or when we have
finished registering all built-in algorithms, whichever comes
earlier.

Reported-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - remove CRYPTOA_U32 and related functions

According to the advice of Eric and Herbert, type CRYPTOA_U32
has been unused for over a decade, so remove the code related to
CRYPTOA_U32.

After removing CRYPTOA_U32, the type of the variable attrs can be
changed from union to struct.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - use common mechanism for inheriting flags

The flag CRYPTO_ALG_ASYNC is "inherited" in the sense that when a
template is instantiated, the template will have CRYPTO_ALG_ASYNC set if
any of the algorithms it uses has CRYPTO_ALG_ASYNC set.

We'd like to add a second flag (CRYPTO_ALG_ALLOCATES_MEMORY) that gets
"inherited" in the same way. This is difficult because the handling of
CRYPTO_ALG_ASYNC is hardcoded everywhere. Address this by:

- Add CRYPTO_ALG_INHERITED_FLAGS, which contains the set of flags that
have these inheritance semantics.

- Add crypto_algt_inherited_mask(), for use by template ->create()
methods. It returns any of these flags that the user asked to be
unset and thus must be passed in the 'mask' to crypto_grab_*().

- Also modify crypto_check_attr_type() to handle computing the 'mask'
so that most templates can just use this.

- Make crypto_grab_*() propagate these flags to the template instance
being created so that templates don't have to do this themselves.

Make crypto/simd.c propagate these flags too, since it "wraps" another
algorithm, similar to a template.

Based on a patch by Mikulas Patocka <mpatocka@redhat.com>
(https://lore.kernel.org/r/alpine.LRH.2.02.2006301414580.30526@file01.intranet.prod.int.rdu2.redhat.com).

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - create function to add request in front of queue

Add crypto_enqueue_request_head function that enqueues a
request in front of queue.
This will be used in crypto-engine, on error path. In case a request
was not executed by hardware, enqueue it back in front of queue (to
keep the order of requests).

Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Fix use-after-free and race in crypto_spawn_alg

There are two problems in crypto_spawn_alg. First of all it may
return spawn->alg even if spawn->dead is set. This results in a
double-free as detected by syzbot.

Secondly the setting of the DYING flag is racy because we hold
the read-lock instead of the write-lock. We should instead call
crypto_shoot_alg in a safe manner by gaining a refcount, dropping
the lock, and then releasing the refcount.

This patch fixes both problems.

Reported-by: syzbot+fc0674cde00b66844470@syzkaller.appspotmail.com
Fixes: 4f87ee118d16 ("crypto: api - Do not zap spawn->alg")
Fixes: 73669cc55646 ("crypto: api - Fix race condition in...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - Avoid spurious modprobe on LOADED

Currently after any algorithm is registered and tested, there's an
unnecessary request_module("cryptomgr") even if it's already loaded.
Also, CRYPTO_MSG_ALG_LOADED is sent twice, and thus if the algorithm is
"crct10dif", lib/crc-t10dif.c replaces the tfm twice rather than once.

This occurs because CRYPTO_MSG_ALG_LOADED is sent using
crypto_probing_notify(), which tries to load "cryptomgr" if the
notification is not handled (NOTIFY_DONE). This doesn't make sense
because "cryptomgr" doesn't handle this notification.

Fix this by using crypto_notify() instead of crypto_probing_notify().

Fixes: dd8b083f9a5e ("crypto: api - Introduce notifier for new crypto algorithms")
Cc: <stable@vger.kernel.org> # v4.20+
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - remove crypto_template::{alloc,free}()

Now that all templates provide a ->create() method which creates an
instance, installs a strongly-typed ->free() method directly to it, and
registers it, the older ->alloc() and ->free() methods in
'struct crypto_template' are no longer used. Remove them.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - fold crypto_init_spawn() into crypto_grab_spawn()

Now that crypto_init_spawn() is only called by crypto_grab_spawn(),
simplify things by moving its functionality into crypto_grab_spawn().

In the process of doing this, also be more consistent about when the
spawn and instance are updated, and remove the crypto_spawn::dropref
flag since now it's always set.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - remove obsoleted instance creation helpers

Remove lots of helper functions that were previously used for
instantiating crypto templates, but are now unused:

- crypto_get_attr_alg() and similar functions looked up an inner
algorithm directly from a template parameter. These were replaced
with getting the algorithm's name, then calling crypto_grab_*().

- crypto_init_spawn2() and similar functions initialized a spawn, given
an algorithm. Similarly, these were replaced with crypto_grab_*().

- crypto_alloc_instance() and similar functions allocated an instance
with a single spawn, given the inner algorithm. These aren't useful
anymore since crypto_grab_*() need the instance allocated first.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - pass instance to crypto_grab_spawn()

Currently, crypto_spawn::inst is first used temporarily to pass the
instance to crypto_grab_spawn(). Then crypto_init_spawn() overwrites it
with crypto_spawn::next, which shares the same union. Finally,
crypto_spawn::inst is set again when the instance is registered.

Make this less convoluted by just passing the instance as an argument to
crypto_grab_spawn() instead.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - make crypto_grab_spawn() handle an ERR_PTR() name

To allow further simplifying template ->create() functions, make
crypto_grab_spawn() handle an ERR_PTR() name by passing back the error.

For most templates, this will allow the result of crypto_attr_alg_name()
to be passed directly to crypto_grab_*(), rather than first having to
assign it to a variable [where it can then potentially be misused, as it
was in the rfc7539 template prior to commit 5e27f38f1f3f ("crypto:
chacha20poly1305 - set cra_name correctly")] and check it for error.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - make crypto_drop_spawn() a no-op on uninitialized spawns

Make crypto_drop_spawn() do nothing when the spawn hasn't been
initialized with an algorithm yet. This will allow simplifying error
handling in all the template ->create() functions, since on error they
will be able to just call their usual "free instance" function, rather
than having to handle dropping just the spawns that have been
initialized so far.

This does assume the spawn starts out zero-filled, but that's always the
case since instances are allocated with kzalloc(). And some other code
already assumes this anyway.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Retain alg refcount in crypto_grab_spawn

This patch changes crypto_grab_spawn to retain the reference count
on the algorithm. This is because the caller needs to access the
algorithm parameters and without the reference count the algorithm
can be freed at any time.

The reference count will be subsequently dropped by the crypto API
once the instance has been registered. The helper crypto_drop_spawn
will also conditionally drop the reference count depending on whether
it has been registered.

Note that the code is actually added to crypto_init_spawn. However,
unless the caller activates this by setting spawn->dropref beforehand
then nothing happens. The only caller that sets dropref is currently
crypto_grab_spawn.

Once all legacy users of crypto_init_spawn disappear, then we can
kill the dropref flag.

Internally each instance will maintain a list of its spawns prior
to registration. This memory used by this list is shared with
other fields that are only used after registration. In order for
this to work a new flag spawn->registered is added to indicate
whether spawn->inst can be used.

Fixes: d6ef2f198d4c ("crypto: api - Add crypto_grab_spawn primitive")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - make unregistration functions return void

Some of the algorithm unregistration functions return -ENOENT when asked
to unregister a non-registered algorithm, while others always return 0
or always return void. But no users check the return value, except for
two of the bulk unregistration functions which print a message on error
but still always return 0 to their caller, and crypto_del_alg() which
calls crypto_unregister_instance() which always returns 0.

Since unregistering a non-registered algorithm is always a kernel bug
but there isn't anything callers should do to handle this situation at
runtime, let's simplify things by making all the unregistration
functions return void, and moving the error message into
crypto_unregister_alg() and upgrading it to a WARN().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - fix unexpectedly getting generic implementation

When CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y, the first lookup of an
algorithm that needs to be instantiated using a template will always get
the generic implementation, even when an accelerated one is available.

This happens because the extra self-tests for the accelerated
implementation allocate the generic implementation for comparison
purposes, and then crypto_alg_tested() for the generic implementation
"fulfills" the original request (i.e. sets crypto_larval::adult).

This patch fixes this by only fulfilling the original request if
we are currently the best outstanding larval as judged by the
priority. If we're not the best then we will ask all waiters on
that larval request to retry the lookup.

Note that this patch introduces a behaviour change when the module
providing the new algorithm is unregistered during the process.
Previously we would have failed with ENOENT, after the patch we
will instead redo the lookup.

Fixes: 9a8a6b3f0950 ("crypto: testmgr - fuzz hashes against...")
Fixes: d435e10e67be ("crypto: testmgr - fuzz skciphers against...")
Fixes: 40153b10d91c ("crypto: testmgr - fuzz AEADs against...")
Reported-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Add more comments to crypto_remove_spawns

This patch explains the logic behind crypto_remove_spawns and its
underling crypto_more_spawns.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Do not zap spawn->alg

Currently when a spawn is removed we will zap its alg field.
This is racy because the spawn could belong to an unregistered
instance which may dereference the spawn->alg field.

This patch fixes this by keeping spawn->alg constant and instead
adding a new spawn->dead field to indicate that a spawn is going
away.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Fix race condition in crypto_spawn_alg

The function crypto_spawn_alg is racy because it drops the lock
before shooting the dying algorithm. The algorithm could disappear
altogether before we shoot it.

This patch fixes it by moving the shooting into the locked section.

Fixes: 6bfd48096ff8 ("[CRYPTO] api: Added spawns")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Check spawn->alg under lock in crypto_drop_spawn

We need to check whether spawn->alg is NULL under lock as otherwise
the algorithm could be removed from under us after we have checked
it and found it to be non-NULL. This could cause us to remove the
spawn from a non-existent list.

Fixes: 7ede5a5ba55a ("crypto: api - Fix crypto_drop_spawn crash...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: ablkcipher - remove deprecated and unused ablkcipher support

Now that all users of the deprecated ablkcipher interface have been
moved to the skcipher interface, ablkcipher is no longer used and
can be removed.

Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - require cra_name and cra_driver_name

Now that all algorithms explicitly set cra_driver_name, make it required
for algorithm registration and remove the code that generated a default
cra_driver_name.

Also add an explicit check that cra_name is set too, since that's
obviously required too, yet it didn't seem to be checked anywhere.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: algapi - remove crypto_tfm_in_queue()

Remove the crypto_tfm_in_queue() function, which is unused.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - add a helper to (un)register a array of templates

This patch add a helper to (un)register a array of templates. The
following patches will use this helper to simplify the code.

Signed-off-by: Xiongfeng Wang <xiongfeng.wang@linaro.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - reject NULL crypto_spawn::inst

It took me a while to notice the bug where the adiantum template left
crypto_spawn::inst == NULL, because this only caused problems in certain
cases where algorithms are dynamically loaded/unloaded.

More improvements are needed, but for now make crypto_init_spawn()
reject this case and WARN(), so this type of bug will be noticed
immediately in the future.

Note: I checked all callers and the adiantum template was the only place
that had this wrong. So this WARN shouldn't trigger anymore.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - remove crypto_alloc_instance()

Now that all "blkcipher" templates have been converted to "skcipher",
crypto_alloc_instance() is no longer used. And it's not useful any
longer as it creates an old-style weakly typed instance rather than a
new-style strongly typed instance. So remove it, and now that the name
is freed up rename crypto_alloc_instance2() to crypto_alloc_instance().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: user - Add crypto_stats_init

This patch add the crypto_stats_init() function.
This will permit to remove some ifdef from __crypto_register_alg().

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: user - rename err_cnt parameter

Since now all crypto stats are on their own structures, it is now
useless to have the algorithm name in the err_cnt member.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: user - Split stats in multiple structures

Like for userspace, this patch splits stats into multiple structures,
one for each algorithm class.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: user - fix use_after_free of struct xxx_request

All crypto_stats functions use the struct xxx_request for feeding stats,
but in some case this structure could already be freed.

For fixing this, the needed parameters (len and alg) will be stored
before the request being executed.
Fixes: cac5818c25d0 ("crypto: user - Implement a generic crypto statistics")
Reported-by: syzbot <syzbot+6939a606a5305e9e9799@syzkaller.appspotmail.com>

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: user - convert all stats from u32 to u64

All the 32-bit fields need to be 64-bit. In some cases, UINT32_MAX crypto
operations can be done in seconds.

Reported-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: user - made crypto_user_stat optional

Even if CRYPTO_STATS is set to n, some part of CRYPTO_STATS are
compiled.
This patch made all part of crypto_user_stat uncompiled in that case.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: user - Implement a generic crypto statistics

This patch implement a generic way to get statistics about all crypto
usages.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Introduce notifier for new crypto algorithms

Introduce a facility that can be used to receive a notification
callback when a new algorithm becomes available. This can be used by
existing crypto registrations to trigger a switch from a software-only
algorithm to a hardware-accelerated version.

A new CRYPTO_MSG_ALG_LOADED state is introduced to the existing crypto
notification chain, and the register/unregister functions are exported
so they can be called by subsystems outside of crypto.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Suggested-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Introduce generic max blocksize and alignmask

In the quest to remove all stack VLA usage from the kernel[1], this
exposes a new general upper bound on crypto blocksize and alignmask
(higher than for the existing cipher limits) for VLA removal,
and introduces new checks.

At present, the highest cra_alignmask in the kernel is 63. The highest
cra_blocksize is 144 (SHA3_224_BLOCK_SIZE, 18 8-byte words). For the
new blocksize limit, I went with 160 (20 8-byte words).

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - laying defines and checks for statically allocated buffers

In preparation for the removal of VLAs[1] from crypto code.
We create 2 new compile-time constants: all ciphers implemented
in Linux have a block size less than or equal to 16 bytes and
the most demanding hw require 16 bytes alignment for the block
buffer.
We also enforce these limits in crypto_check_alg when a new
cipher is registered.

[1] http://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Keep failed instances alive

This patch reverts commit 9c521a200bc3 ("crypto: api - remove
instance when test failed") and fixes the underlying problem
in a different way.

To recap, prior to the reverted commit, an instance that fails
a self-test is kept around. However, it would satisfy any new
lookups against its name and therefore the system may accumlulate
an unbounded number of failed instances for the same algorithm
name.

The reverted commit fixed it by unregistering the instance. Hoever,
this still does not prevent the creation of the same failed instance
over and over again each time the name is looked up.

This patch fixes it by keeping the failed instance around, just as
we would if it were a normal algorithm. However, the lookup code
has been udpated so that we do not attempt to create another
instance as long as this failed one is still registered. Of course,
you could still force a new creation by deleting the instance from
user-space.

A new error (ELIBBAD) has been commandeered for this purpose and
will be returned when all registered algorithm of a given name
have failed the self-test.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - remove unused notifications

There is a message posted to the crypto notifier chain when an algorithm
is unregistered, and when a template is registered or unregistered. But
nothing is listening for those messages; currently there are only
listeners for the algorithm request and registration messages.

Get rid of these unused notifications for now.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - convert cra_refcnt to refcount_t

Reference counters should use refcount_t rather than atomic_t, since the
refcount_t implementation can prevent overflows, reducing the
exploitability of reference leak bugs. crypto_alg.cra_refcount is a
reference counter with the usual semantics, so switch it over to
refcount_t.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - fix NULL dereference in crypto_remove_spawns()

syzkaller triggered a NULL pointer dereference in crypto_remove_spawns()
via a program that repeatedly and concurrently requests AEADs
"authenc(cmac(des3_ede-asm),pcbc-aes-aesni)" and hashes "cmac(des3_ede)"
through AF_ALG, where the hashes are requested as "untested"
(CRYPTO_ALG_TESTED is set in ->salg_mask but clear in ->salg_feat; this
causes the template to be instantiated for every request).

Although AF_ALG users really shouldn't be able to request an "untested"
algorithm, the NULL pointer dereference is actually caused by a
longstanding race condition where crypto_remove_spawns() can encounter
an instance which has had spawn(s) "grabbed" but hasn't yet been
registered, resulting in ->cra_users still being NULL.

We probably should properly initialize ->cra_users earlier, but that
would require updating many templates individually. For now just fix
the bug in a simple way that can easily be backported: make
crypto_remove_spawns() treat a NULL ->cra_users list as empty.

Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: change transient busy return code to -ENOSPC

The crypto API was using the -EBUSY return value to indicate
both a hard failure to submit a crypto operation into a
transformation provider when the latter was busy and the backlog
mechanism was not enabled as well as a notification that the
operation was queued into the backlog when the backlog mechanism
was enabled.

Having the same return code indicate two very different conditions
depending on a flag is both error prone and requires extra runtime
check like the following to discern between the cases:

if (err == -EINPROGRESS ||
(err == -EBUSY && (ahash_request_flags(req) &
CRYPTO_TFM_REQ_MAY_BACKLOG)))

This patch changes the return code used to indicate a crypto op
failed due to the transformation provider being transiently busy
to -ENOSPC.

Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - use separate dst and src operands for __crypto_xor()

In preparation of introducing crypto_xor_cpy(), which will use separate
operands for input and output, modify the __crypto_xor() implementation,
which it will share with the existing crypto_xor(), which provides the
actual functionality when not using the inline version.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - Use pr_err common logging style.

Use more common error logging style.

Signed-off-by: Karim Eshapa <karim.eshapa@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - annotate expected branch behavior in crypto_inc()

To prevent unnecessary branching, mark the exit condition of the
primary loop as likely(), given that a carry in a 32-bit counter
occurs very rarely.

On arm64, the resulting code is emitted by GCC as

9a8: cmp w1, #0x3
9ac: add x3, x0, w1, uxtw
9b0: b.ls 9e0 <crypto_inc+0x38>
9b4: ldr w2, [x3,#-4]!
9b8: rev w2, w2
9bc: add w2, w2, #0x1
9c0: rev w4, w2
9c4: str w4, [x3]
9c8: cbz w2, 9d0 <crypto_inc+0x28>
9cc: ret

where the two remaining branch conditions (one for size < 4 and one for
the carry) are statically predicted as non-taken, resulting in optimal
execution in the vast majority of cases.

Also, replace the open coded alignment test with IS_ALIGNED().

Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - make crypto_xor() and crypto_inc() alignment agnostic

Instead of unconditionally forcing 4 byte alignment for all generic
chaining modes that rely on crypto_xor() or crypto_inc() (which may
result in unnecessary copying of data when the underlying hardware
can perform unaligned accesses efficiently), make those functions
deal with unaligned input explicitly, but only if the Kconfig symbol
HAVE_EFFICIENT_UNALIGNED_ACCESS is set. This will allow us to drop
the alignmasks from the CBC, CMAC, CTR, CTS, PCBC and SEQIV drivers.

For crypto_inc(), this simply involves making the 4-byte stride
conditional on HAVE_EFFICIENT_UNALIGNED_ACCESS being set, given that
it typically operates on 16 byte buffers.

For crypto_xor(), an algorithm is implemented that simply runs through
the input using the largest strides possible if unaligned accesses are
allowed. If they are not, an optimal sequence of memory accesses is
emitted that takes the relative alignment of the input buffers into
account, e.g., if the relative misalignment of dst and src is 4 bytes,
the entire xor operation will be completed using 4 byte loads and stores
(modulo unaligned bits at the start and end). Note that all expressions
involving misalign are simply eliminated by the compiler when
HAVE_EFFICIENT_UNALIGNED_ACCESS is defined.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Clear CRYPTO_ALG_DEAD bit before registering an alg

Make sure CRYPTO_ALG_DEAD bit is cleared before proceeding with
the algorithm registration. This fixes qat-dh registration when
driver is restarted

Cc: <stable@vger.kernel.org>
Signed-off-by: Salvatore Benedetto <salvatore.benedetto@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Add crypto_inst_setname

This patch adds the helper crypto_inst_setname because the current
helper crypto_alloc_instance2 is no longer useful given that we
now look up the algorithm after we allocate the instance object.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Add crypto_type_has_alg helper

This patch adds the helper crypto_type_has_alg which is meant
to replace crypto_has_alg for new-style crypto types. Rather
than hard-coding type/mask information they're now retrieved
from the crypto_type object.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - use list_first_entry_or_null and list_next_entry

Simplify crypto_more_spawns() with list_first_entry_or_null()
and list_next_entry().

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Only abort operations on fatal signal

Currently a number of Crypto API operations may fail when a signal
occurs. This causes nasty problems as the caller of those operations
are often not in a good position to restart the operation.

In fact there is currently no need for those operations to be
interrupted by user signals at all. All we need is for them to
be killable.

This patch replaces the relevant calls of signal_pending with
fatal_signal_pending, and wait_for_completion_interruptible with
wait_for_completion_killable, respectively.

Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Add instance free function to crypto_type

Currently the task of freeing an instance is given to the crypto
template. However, it has no type information on the instance so
we have to resort to checking type information at runtime.

This patch introduces a free function to crypto_type that will be
used to free an instance. This can then be used to free an instance
in a type-safe manner.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Remove unused __crypto_dequeue_request

The function __crypto_dequeue_request is completely unused.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Include alignment in crypto_alg_extsize

This patch ensures that the tfm context always has enough extra
memory to ensure that it is aligned according to cra_alignment.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Add crypto_grab_spawn primitive

This patch adds a new primitive crypto_grab_spawn which is meant
to replace crypto_init_spawn and crypto_init_spawn2. Under the
new scheme the user no longer has to worry about reference counting
the alg object before it is subsumed by the spawn.

It is pretty much an exact copy of crypto_grab_aead.

Prior to calling this function spawn->frontend and spawn->inst
must have been set.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Fix build error when modules are disabled

The commit 59afdc7b32143528524455039e7557a46b60e4c8 ("crypto:
api - Move module sig ifdef into accessor function") broke the
build when modules are completely disabled because we directly
dereference module->name.

This patch fixes this by using the accessor function module_name.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Include linux/fips.h

All users of fips_enabled should include linux/fips.h directly
instead of getting it through internal.h.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Move module sig ifdef into accessor function

Currently we're hiding mod->sig_ok under an ifdef in open code.
This patch adds a module_sig_ok accessor function and removes that
ifdef.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>

crypto: api - Add crypto_alg_extsize helper

This patch adds a crypto_alg_extsize helper that can be used
by algorithm types such as pcompress and shash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: fix broken crypto_register_instance() module handling

Commit 9c521a200bc3 ("crypto: api - remove instance when test failed")
tried to grab a module reference count before the module was even set.

Worse, it then goes on to free the module reference count after it is
set so you quickly end up with a negative module reference count which
prevents people from using any instances belonging to that module.

This patch moves the module initialisation before the reference
count.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

crypto: api - remove instance when test failed

A cipher instance is added to the list of instances unconditionally
regardless of whether the associated test failed. However, a failed
test implies that during another lookup, the cipher instance will
be added to the list again as it will not be found by the lookup
code.

That means that the list can be filled up with instances whose tests
failed.

Note: tests only fail in reality in FIPS mode when a cipher is not
marked as fips_allowed=1. This can be seen with cmac(des3_ede) that does
not have a fips_allowed=1. When allocating the cipher, the allocation
fails with -ENOENT due to the missing fips_allowed=1 flag (which
causes the testmgr to return EINVAL). Yet, the instance of
cmac(des3_ede) is shown in /proc/crypto. Allocating the cipher again
fails again, but a 2nd instance is listed in /proc/crypto.

The patch simply de-registers the instance when the testing failed.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Move alg ref count init to crypto_check_alg

We currently initialise the crypto_alg ref count in the function
__crypto_register_alg. As one of the callers of that function
crypto_register_instance needs to obtain a ref count before it
calls __crypto_register_alg, we need to move the initialisation
out of there.

Since both callers of __crypto_register_alg call crypto_check_alg,
this is the logical place to perform the initialisation.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Stephan Mueller <smueller@chronox.de>

crypto: api - Change crypto_unregister_instance argument type

This patch makes crypto_unregister_instance take a crypto_instance
instead of a crypto_alg. This allows us to remove a duplicate
CRYPTO_ALG_INSTANCE check in crypto_unregister_instance.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Fix races in crypto_unregister_instance

There are multiple problems in crypto_unregister_instance:

1) The cra_refcnt BUG_ON check is racy and can cause crashes.
2) The cra_refcnt check shouldn't exist at all.
3) There is no reference on tmpl to protect the tmpl->free call.

This patch rewrites the function using crypto_remove_spawn which
now morphs into crypto_remove_instance.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - fixed style erro in algapi.c

Fixed style error identified by checkpatch.

WARNING: Missing a blank line after declarations
+ int err = crypto_remove_alg(&inst->alg, &users);
+ BUG_ON(err);

Signed-off-by: Joshua I. James <joshua@cybercrimetech.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: include crypto- module prefix in template

This adds the module loading prefix "crypto-" to the template lookup
as well.

For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly
includes the "crypto-" prefix at every level, correctly rejecting "vfat":

net-pf-38
algif-hash
crypto-vfat(blowfish)
crypto-vfat(blowfish)-all
crypto-vfat

Reported-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: fips - only panic on bad/missing crypto mod signatures

Per further discussion with NIST, the requirements for FIPS state that
we only need to panic the system on failed kernel module signature checks
for crypto subsystem modules. This moves the fips-mode-only module
signature check out of the generic module loading code, into the crypto
subsystem, at points where we can catch both algorithm module loads and
mode module loads. At the same time, make CONFIG_CRYPTO_FIPS dependent on
CONFIG_MODULE_SIG, as this is entirely necessary for FIPS mode.

v2: remove extraneous blank line, perform checks in static inline
function, drop no longer necessary fips.h include.

CC: "David S. Miller" <davem@davemloft.net>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Stephan Mueller <stephan.mueller@atsec.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sanitize argument for format string

The template lookup interface does not provide a way to use format
strings, so make sure that the interface cannot be abused accidentally.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hlist: drop the node parameter from iterators

I'm not sure why, but the hlist for each entry iterators were conceived

list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

- Fix up the actual hlist iterators in linux/list.h
- Fix up the declaration of other iterators based on the hlist ones.
- A very small amount of places were using the 'node' parameter, this
was modified to use 'obj->member' instead.
- Coccinelle didn't handle the hlist_for_each_entry_safe iterator
properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
<+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

crypto: use ERR_CAST

Replace PTR_ERR followed by ERR_PTR by ERR_CAST, to be more concise.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression err,x;
@@
- err = PTR_ERR(x);
if (IS_ERR(x))
- return ERR_PTR(err);
+ return ERR_CAST(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - Move larval completion into algboss

It has been observed that sometimes the crypto allocation code
will get stuck for 60 seconds or multiples thereof. This is
usually caused by an algorithm failing to pass the self-test.

If an algorithm fails to be constructed, we will immediately notify
all larval waiters. However, if it succeeds in construction, but
then fails the self-test, we won't notify anyone at all.

This patch fixes this by merging the notification in the case
where the algorithm fails to be constructed with that of the
the case where it pases the self-test. This way regardless of
what happens, we'll give the larval waiters an answer.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: Add bulk algorithm registration interface

Hardware crypto engines frequently need to register a selection of
different algorithms with the core. Simplify their code slightly,
especially the error handling, by providing functions to register a
number of algorithms in a single call.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: Unlink and free instances when deleted

We leak the crypto instance when we unregister an instance with
crypto_del_alg(). Therefore we introduce crypto_unregister_instance()
to unlink the crypto instance from the template's instances list and
to free the recources of the instance properly.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: Export crypto_remove_final

The upcomming crypto usrerspace configuration api needs
to remove the spawns on top on an algorithm, so export
crypto_remove_final.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: Export crypto_remove_spawns

The upcomming crypto usrerspace configuration api needs
to remove the spawns on top on an algorithm, so export
crypto_remove_spawns.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: Add a flag to identify crypto instances

The upcomming crypto user configuration api needs to identify
crypto instances. This patch adds a flag that is set if the
algorithm is an instance that is build from templates.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: algapi - Remove unneeded null check

We don't check "frontend" consistently in crypto_init_spawn2(). We
check it at the start of the function but then we dereference it
unconditionally in the parameter list when we call crypto_init_spawn().

I looked at the places that call crypto_init_spawn2() and "frontend" is
always a valid pointer so I removed the check for null.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

crypto: algapi - Fix checkpatch errors

Signed-off-by: Richard Hartmann <richih.mailinglist@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Do not displace newly registered algorithms

We have a mechanism where newly registered algorithms of a higher
priority can displace existing instances that use a different
implementation of the same algorithm with a lower priority.

Unfortunately the same mechanism can cause a newly registered
algorithm to displace itself if it depends on an existing version
of the same algorithm.

This patch fixes this by keeping all algorithms that the newly
reigstered algorithm depends on, thus protecting them from being
removed.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: skcipher - Fix skcipher_dequeue_givcrypt NULL test

As struct skcipher_givcrypt_request includes struct crypto_request
at a non-zero offset, testing for NULL after converting the pointer
returned by crypto_dequeue_request does not work. This can result
in IPsec crashes when the queue is depleted.

This patch fixes it by doing the pointer conversion only when the
return value is non-NULL. In particular, we create a new function
__crypto_dequeue_request that does the pointer conversion.

Reported-by: Brad Bosch <bradbosch@comcast.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Fix crypto_drop_spawn crash on blank spawns

This patch allows crypto_drop_spawn to be called on spawns that
have not been initialised or have failed initialisation. This
fixes potential crashes during initialisation without adding
special case code.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Add crypto_attr_alg2 helper

This patch adds the helper crypto_attr_alg2 which is similar to
crypto_attr_alg but takes an extra frontend argument. This is
intended to be used by new style algorithm types such as shash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Add new style spawn support

This patch modifies the spawn infrastructure to support new style
algorithms like shash. In particular, this means storing the
frontend type in the spawn and using crypto_create_tfm to allocate
the tfm.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Add crypto_alloc_instance2

This patch adds a new argument to crypto_alloc_instance which
sets aside some space before the instance for use by algorithms
such as shash that place type-specific data before crypto_alg.

For compatibility the function has been renamed so that existing
users aren't affected.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Fix algorithm test race that broke aead initialisation

When we complete a test we'll notify everyone waiting on it, drop
the mutex, and then remove the test larval (after reacquiring the
mutex). If one of the notified parties tries to register another
algorithm with the same driver name prior to the removal of the
test larval, they will fail with EEXIST as only one algorithm of
a given name can be tested at any time.

This broke the initialisation of aead and givcipher algorithms as
they will register two algorithms with the same driver name, in
sequence.

This patch fixes the problem by marking the larval as dead before
we drop the mutex, and also ignoring all dead or dying algorithms
on the registration path.

Tested-by: Andreas Steffen <andreas.steffen@strongswan.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Use test infrastructure

This patch makes use of the new testing infrastructure by requiring
algorithms to pass a run-time test before they're made available to
users.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Export crypto_alg_lookup instead of __crypto_alg_lookup

Since the only user of __crypto_alg_lookup is doing exactly what
crypto_alg_lookup does, we can now the latter in lieu of the former.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Add crypto_attr_alg_name

This patch adds a new helper crypto_attr_alg_name which is basically the
first half of crypto_attr_alg. That is, it returns an algorithm name
parameter as a string without looking it up. The caller can then look it
up immediately or defer it until later.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Add crypto_inc and crypto_xor

With the addition of more stream ciphers we need to curb the proliferation
of ad-hoc xor functions. This patch creates a generic pair of functions,
crypto_inc and crypto_xor which does big-endian increment and exclusive or,
respectively.

For optimum performance, they both use u32 operations so alignment must be
as that of u32 even though the arguments are of type u8 *.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Fix potential race in crypto_remove_spawn

As it is crypto_remove_spawn may try to unregister an instance which is
yet to be registered. This patch fixes this by checking whether the
instance has been registered before attempting to remove it.

It also removes a bogus cra_destroy check in crypto_register_instance as
1) it's outside the mutex;
2) we have a check in __crypto_register_alg already.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Explain the comparison on larval cra_name

This patch adds a comment to explain why we compare the cra_driver_name of
the algorithm being registered against the cra_name of a larval as opposed
to the cra_driver_name of the larval.

In fact larvals have only one name, cra_name which is the name that was
requested by the user. The test here is simply trying to find out whether
the algorithm being registered can or can not satisfy the larval.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] blkcipher: Remove alignment restriction on block size

Previously we assumed for convenience that the block size is a multiple of
the algorithm's required alignment. With the pending addition of CTR this
will no longer be the case as the block size will be 1 due to it being a
stream cipher. However, the alignment requirement will be that of the
underlying implementation which will most likely be greater than 1.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] aead: Add authenc

This patch adds the authenc algorithm which constructs an AEAD algorithm
from an asynchronous block cipher and a hash. The construction is done
by concatenating the encrypted result from the cipher with the output
from the hash, as is used by the IPsec ESP protocol.

The authenc algorithm exists as a template with four parameters:

authenc(auth, authsize, enc, enckeylen).

The authentication algorithm, the authentication size (i.e., truncating
the output of the authentication algorithm), the encryption algorithm,
and the encryption key length. Both the size field and the key length
field are in bytes. For example, AES-128 with SHA1-HMAC would be
represented by

authenc(hmac(sha1), 12, cbc(aes), 16)

The key for the authenc algorithm is the concatenation of the keys for
the authentication algorithm with the encryption algorithm. For the
above example, if a key of length 36 bytes is given, then hmac(sha1)
would receive the first 20 bytes while the last 16 would be given to
cbc(aes).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Add support for multiple template parameters

This patch adds support for having multiple parameters to
a template, separated by a comma. It also adds support
for integer parameters in addition to the current algorithm
parameter type.

This will be used by the authenc template which will have
four parameters: the authentication algorithm, the encryption
algorithm, the authentication size and the encryption key
length.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Wake up all waiters when larval completes

Right now when a larval matures or when it dies of an error we
only wake up one waiter. This would cause other waiters to timeout
unnecessarily. This patch changes it to use complete_all to wake
up all waiters.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Do not remove users unless new algorithm matches

As it is whenever a new algorithm with the same name is registered
users of the old algorithm will be removed so that they can take
advantage of the new algorithm. This presents a problem when the
new algorithm is not equivalent to the old algorithm. In particular,
the new algorithm might only function on top of the existing one.

Hence we should not remove users unless they can make use of the
new algorithm.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Add async blkcipher type

This patch adds the mid-level interface for asynchronous block ciphers.
It also includes a generic queueing mechanism that can be used by other
asynchronous crypto operations in future.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] templates: Pass type/mask when creating instances

This patch passes the type/mask along when constructing instances of
templates. This is in preparation for templates that may support
multiple types of instances depending on what is requested. For example,
the planned software async crypto driver will use this construct.

For the moment this allows us to check whether the instance constructed
is of the correct type and avoid returning success if the type does not
match.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Allow multiple frontends per backend

This patch adds support for multiple frontend types for each backend
algorithm by passing the type and mask through to the backend type
init function.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Add type-safe spawns

This patch allows spawns of specific types (e.g., cipher) to be allocated.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Remove deprecated interface

This patch removes the old cipher interface and related code.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Add common instance initialisation code

This patch adds the helpers crypto_get_attr_alg and crypto_alloc_instance
which can be used by simple one-argument templates like hmac to process
input parameters and allocate instances.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] api: Added spawns

Spawns lock a specific crypto algorithm in place. They can then be used
with crypto_spawn_tfm to allocate a tfm for that algorithm. When the base
algorithm of a spawn is deregistered, all its spawns will be automatically
removed.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

[CRYPTO] api: Allow algorithm lookup by type

This patch also adds the infrastructure to pick an algorithm based on
their type. For example, this allows you to select the encryption
algorithm "aes", instead of any algorithm registered under the name
"aes". For now this is only accessible internally. Eventually it
will be made available through crypto_alloc_tfm.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

[CRYPTO] api: Added event notification

This patch adds a notifier chain for algorithm/template registration events.
This will be used to register compound algorithms such as cbc(aes). In
future this will also be passed onto user-space through netlink.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

[CRYPTO] api: Add template registration

A crypto_template generates a crypto_alg object when given a set of
parameters. this patch adds the basic data structure fo templates
and code to handle their registration/deregistration.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

[CRYPTO] api: Split out low-level API

The crypto API is made up of the part facing users such as IPsec and the
low-level part which is used by cryptographic entities such as algorithms.
This patch splits out the latter so that the two APIs are more clearly
delineated. As a bonus the low-level API can now be modularised if all
algorithms are built as modules.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>