Revert "crypto: remove CONFIG_CRYPTO_STATS"

This reverts commit 2beb81fbf0c01a62515a1bcef326168494ee2bd0.

While removing CONFIG_CRYPTO_STATS is a worthy goal, this also
removed unrelated infrastructure such as crypto_comp_alg_common.

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

crypto: remove CONFIG_CRYPTO_STATS

Remove support for the "Crypto usage statistics" feature
(CONFIG_CRYPTO_STATS). This feature does not appear to have ever been
used, and it is harmful because it significantly reduces performance and
is a large maintenance burden.

Covering each of these points in detail:

1. Feature is not being used

Since these generic crypto statistics are only readable using netlink,
it's fairly straightforward to look for programs that use them. I'm
unable to find any evidence that any such programs exist. For example,
Debian Code Search returns no hits except the kernel header and kernel
code itself and translations of the kernel header:
https://codesearch.debian.net/search?q=CRYPTOCFGA_STAT&literal=1&perpkg=1

The patch series that added this feature in 2018
(https://lore.kernel.org/linux-crypto/1537351855-16618-1-git-send-email-clabbe@baylibre.com/)
said "The goal is to have an ifconfig for crypto device." This doesn't
appear to have happened.

It's not clear that there is real demand for crypto statistics. Just
because the kernel provides other types of statistics such as I/O and
networking statistics and some people find those useful does not mean
that crypto statistics are useful too.

Further evidence that programs are not using CONFIG_CRYPTO_STATS is that
it was able to be disabled in RHEL and Fedora as a bug fix
(https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/2947).

Even further evidence comes from the fact that there are and have been
bugs in how the stats work, but they were never reported. For example,
before Linux v6.7 hash stats were double-counted in most cases.

There has also never been any documentation for this feature, so it
might be hard to use even if someone wanted to.

2. CONFIG_CRYPTO_STATS significantly reduces performance

Enabling CONFIG_CRYPTO_STATS significantly reduces the performance of
the crypto API, even if no program ever retrieves the statistics. This
primarily affects systems with large number of CPUs. For example,
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2039576 reported
that Lustre client encryption performance improved from 21.7GB/s to
48.2GB/s by disabling CONFIG_CRYPTO_STATS.

It can be argued that this means that CONFIG_CRYPTO_STATS should be
optimized with per-cpu counters similar to many of the networking
counters. But no one has done this in 5+ years. This is consistent
with the fact that the feature appears to be unused, so there seems to
be little interest in improving it as opposed to just disabling it.

It can be argued that because CONFIG_CRYPTO_STATS is off by default,
performance doesn't matter. But Linux distros tend to error on the side
of enabling options. The option is enabled in Ubuntu and Arch Linux,
and until recently was enabled in RHEL and Fedora (see above). So, even
just having the option available is harmful to users.

3. CONFIG_CRYPTO_STATS is a large maintenance burden

There are over 1000 lines of code associated with CONFIG_CRYPTO_STATS,
spread among 32 files. It significantly complicates much of the
implementation of the crypto API. After the initial submission, many
fixes and refactorings have consumed effort of multiple people to keep
this feature "working". We should be spending this effort elsewhere.

Cc: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: shash - remove crypto_shash_ctx_aligned()

crypto_shash_ctx_aligned() is no longer used, and it is useless now that
shash algorithms don't support nonzero alignmasks, so remove it.

Also remove crypto_tfm_ctx_aligned() which was only called by
crypto_shash_ctx_aligned(). It's unlikely to be useful again, since it
seems inappropriate to use cra_alignmask to represent alignment for the
tfm context when it already means alignment for inputs/outputs.

Signed-off-by: Eric Biggers <ebiggers@google.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: api - Remove crypto_init_ops()

Purge crypto_type::init() as well.
The last user seems to be gone with commit d63007eb954e ("crypto:
ablkcipher - remove deprecated and unused ablkcipher support").

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

crypto: api - Move low-level functions into algapi.h

A number of low-level functions were exposed in crypto.h. Move
them into algapi.h (and internal.h).

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

crypto: lib/utils - Move utilities into new header

The utilities have historically resided in algapi.h as they were
first used internally before being exported. Move them into a
new header file so external users don't see internal API details.

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

crypto: api - Move MODULE_ALIAS_CRYPTO to algapi.h

This is part of the low-level API and should not be exposed to
top-level Crypto API users.

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

crypto: algapi - Move stat reporting into algapi

The stats code resurrected the unions from the early days of
kernel crypto. This patch starts the process of moving them
out to the individual type structures as we do for everything
else.

In particular, add a report_stat function to cra_type and call
that from the stats code if available. This allows us to move
the actual code over one-by-one.

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

crypto: api - Use data directly in completion function

This patch does the final flag day conversion of all completion
functions which are now all contained in the Crypto API.

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

crypto: api - Add scaffolding to change completion function signature

The crypto completion function currently takes a pointer to a
struct crypto_async_request object. However, in reality the API
does not allow the use of any part of the object apart from the
data field. For example, ahash/shash will create a fake object
on the stack to pass along a different data field.

This leads to potential bugs where the user may try to dereference
or otherwise use the crypto_async_request object.

This patch adds some temporary scaffolding so that the completion
function can take a void * instead. Once affected users have been
converted this can be removed.

The helper crypto_request_complete will remain even after the
conversion is complete. It should be used instead of calling
the completion function directly.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Use linux/cache.h instead of asm/cache.h

Directly including asm/cache.h leads to build failures on powerpc
so replace it with linux/cache.h instead.

Fixes: e634ac4a8aaa ("crypto: api - Add crypto_tfm_ctx_dma")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Increase MAX_ALGAPI_ALIGNMASK to 127

Previously we limited the maximum alignment mask to 63. This
is mostly due to stack usage for shash. This patch introduces
a separate limit for shash algorithms and increases the general
limit to 127 which is the value that we need for DMA allocations
on arm64.

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

crypto: api - Add crypto_tfm_ctx_dma

This patch adds the helpers crypto_tfm_ctx_aligned and
crypto_tfm_ctx_dma. The first aligns the tfm context to the
value cra_alignmask. The second sets the alignment according
to dma_cache_get_alignment();

This patch also moves crypto_tfm_ctx into algapi.h.

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 - Replace kernel.h with the necessary inclusions

When kernel.h is used in the headers it adds a lot into dependency hell,
especially when there are circular dependencies are involved.

Replace kernel.h inclusion with the list of what is really being used.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Move crypto attr definitions out of crypto.h

The definitions for crypto_attr-related types and enums are not
needed by most Crypto API users. This patch moves them out of
crypto.h and into algapi.h/internal.h depending on the extent of
their use.

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: remove cipher routines from public crypto API

The cipher routines in the crypto API are mostly intended for templates
implementing skcipher modes generically in software, and shouldn't be
used outside of the crypto subsystem. So move the prototypes and all
related definitions to a new header file under include/crypto/internal.
Also, let's use the new module namespace feature to move the symbol
exports into a new namespace CRYPTO_INTERNAL.

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

crypto: algapi - Remove skbuff.h inclusion

The header file algapi.h includes skbuff.h unnecessarily since
all we need is a forward declaration for struct sk_buff. This
patch removes that inclusion.

Unfortunately skbuff.h pulls in a lot of things and drivers over
the years have come to rely on it so this patch adds a lot of
missing inclusions that result from this.

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

crypto: algapi - Move crypto_yield into internal.h

This patch moves crypto_yield into internal.h as it's only used
by internal code such as skcipher. It also adds a missing inclusion
of sched.h which is required for cond_resched.

The header files in internal.h have been cleaned up to remove some
ancient junk and add some more specific inclusions.

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

crypto: algapi - introduce the flag CRYPTO_ALG_ALLOCATES_MEMORY

Introduce a new algorithm flag CRYPTO_ALG_ALLOCATES_MEMORY. If this
flag is set, then the driver allocates memory in its request routine.
Such drivers are not suitable for disk encryption because GFP_ATOMIC
allocation can fail anytime (causing random I/O errors) and GFP_KERNEL
allocation can recurse into the block layer, causing a deadlock.

For now, this flag is only implemented for some algorithm types. We
also assume some usage constraints for it to be meaningful, since there
are lots of edge cases the crypto API allows (e.g., misaligned or
fragmented scatterlists) that mean that nearly any crypto algorithm can
allocate memory in some case. See the comment for details.

Also add this flag to CRYPTO_ALG_INHERITED_FLAGS so that when a template
is instantiated, this flag is set on the template instance if it is set
on any algorithm the instance uses.

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 - add NEED_FALLBACK to INHERITED_FLAGS

CRYPTO_ALG_NEED_FALLBACK is handled inconsistently. When it's requested
to be clear, some templates propagate that request to child algorithms,
while others don't.

It's apparently desired for NEED_FALLBACK to be propagated, to avoid
deadlocks where a module tries to load itself while it's being
initialized, and to avoid unnecessarily complex fallback chains where we
have e.g. cbc-aes-$driver falling back to cbc(aes-$driver) where
aes-$driver itself falls back to aes-generic, instead of cbc-aes-$driver
simply falling back to cbc(aes-generic). There have been a number of
fixes to this effect:

commit 89027579bc6c ("crypto: xts - Propagate NEED_FALLBACK bit")
commit d2c2a85cfe82 ("crypto: ctr - Propagate NEED_FALLBACK bit")
commit e6c2e65c70a6 ("crypto: cbc - Propagate NEED_FALLBACK bit")

But it seems that other templates can have the same problems too.

To avoid this whack-a-mole, just add NEED_FALLBACK to INHERITED_FLAGS so
that it's always inherited.

Signed-off-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: 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: cipher - make crypto_spawn_cipher() take a crypto_cipher_spawn

Now that all users of single-block cipher spawns have been converted to
use 'struct crypto_cipher_spawn' rather than the less specifically typed
'struct crypto_spawn', make crypto_spawn_cipher() take a pointer to a
'struct crypto_cipher_spawn' rather than a 'struct crypto_spawn'.

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

crypto: cipher - introduce crypto_cipher_spawn and crypto_grab_cipher()

Currently, "cipher" (single-block cipher) spawns are usually initialized
by using crypto_get_attr_alg() to look up the algorithm, then calling
crypto_init_spawn(). In one case, crypto_grab_spawn() is used directly.

The former way is different from how skcipher, aead, and akcipher spawns
are initialized (they use crypto_grab_*()), and for no good reason.
This difference introduces unnecessary complexity.

The crypto_grab_*() functions used to have some problems, like not
holding a reference to the algorithm and requiring the caller to
initialize spawn->base.inst. But those problems are fixed now.

Also, the cipher spawns are not strongly typed; e.g., the API requires
that the user manually specify the flags CRYPTO_ALG_TYPE_CIPHER and
CRYPTO_ALG_TYPE_MASK. Though the "cipher" algorithm type itself isn't
yet strongly typed, we can start by making the spawns strongly typed.

So, let's introduce a new 'struct crypto_cipher_spawn', and functions
crypto_grab_cipher() and crypto_drop_cipher() to grab and drop them.

Later patches will convert all cipher spawns to use these, then make
crypto_spawn_cipher() take 'struct crypto_cipher_spawn' as well, instead
of a bare 'struct crypto_spawn' as it currently does.

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: 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 - 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: 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: skcipher - remove the "blkcipher" algorithm type

Now that all "blkcipher" algorithms have been converted to "skcipher",
remove the blkcipher algorithm type.

The skcipher (symmetric key cipher) algorithm type was introduced a few
years ago to replace both blkcipher and ablkcipher (synchronous and
asynchronous block cipher). The advantages of skcipher include:

- A much less confusing name, since none of these algorithm types have
ever actually been for raw block ciphers, but rather for all
length-preserving encryption modes including block cipher modes of
operation, stream ciphers, and other length-preserving modes.

- It unified blkcipher and ablkcipher into a single algorithm type
which supports both synchronous and asynchronous implementations.
Note, blkcipher already operated only on scatterlists, so the fact
that skcipher does too isn't a regression in functionality.

- Better type safety by using struct skcipher_alg, struct
crypto_skcipher, etc. instead of crypto_alg, crypto_tfm, etc.

- It sometimes simplifies the implementations of algorithms.

Also, the blkcipher API was no longer being tested.

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

crypto: api - Remove redundant #ifdef in crypto_yield()

While looking at CONFIG_PREEMPT dependencies treewide the #ifdef in
crypto_yield() matched.

CONFIG_PREEMPT and CONFIG_PREEMPT_VOLUNTARY are mutually exclusive so the
extra !CONFIG_PREEMPT conditional is redundant.

cond_resched() has only an effect when CONFIG_PREEMPT_VOLUNTARY is set,
otherwise it's a stub which the compiler optimizes out.

Remove the whole conditional.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-crypto@vger.kernel.org
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
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 - 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: 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 - Remove unused crypto_type lookup function

The lookup function in crypto_type was only used for the implicit
IV generators which have been completely removed from the crypto
API.

This patch removes the lookup function as it is now useless.

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

crypto: algapi - make crypto_xor() take separate dst and src arguments

There are quite a number of occurrences in the kernel of the pattern

if (dst != src)
memcpy(dst, src, walk.total % AES_BLOCK_SIZE);
crypto_xor(dst, final, walk.total % AES_BLOCK_SIZE);

or

crypto_xor(keystream, src, nbytes);
memcpy(dst, keystream, nbytes);

where crypto_xor() is preceded or followed by a memcpy() invocation
that is only there because crypto_xor() uses its output parameter as
one of the inputs. To avoid having to add new instances of this pattern
in the arm64 code, which will be refactored to implement non-SIMD
fallbacks, add an alternative implementation called crypto_xor_cpy(),
taking separate input and output arguments. This removes the need for
the separate memcpy().

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
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: api - Add crypto_requires_off helper

This patch adds crypto_requires_off which is an extension of
crypto_requires_sync for similar bits such as NEED_FALLBACK.

Cc: stable@vger.kernel.org #4.10
Suggested-by: Marcelo Cerri <marcelo.cerri@canonical.com>
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: engine - move crypto engine to its own header

This patch move the whole crypto engine API to its own header
crypto/engine.h.

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

crypto: api - Optimise away crypto_yield when hard preemption is on

When hard preemption is enabled there is no need to explicitly
call crypto_yield. This patch eliminates it if that is the case.

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: hash - Remove crypto_hash interface

This patch removes all traces of the crypto_hash interface, now
that everyone has switched over to shash or ahash.

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

crypto: engine - Introduce the block request crypto engine framework

Now block cipher engines need to implement and maintain their own queue/thread
for processing requests, moreover currently helpers provided for only the queue
itself (in crypto_enqueue_request() and crypto_dequeue_request()) but they
don't help with the mechanics of driving the hardware (things like running the
request immediately, DMA map it or providing a thread to process the queue in)
even though a lot of that code really shouldn't vary that much from device to
device.

Thus this patch provides a mechanism for pushing requests to the hardware
as it becomes free that drivers could use. And this framework is patterned
on the SPI code and has worked out well there.
(https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/
drivers/spi/spi.c?id=ffbbdd21329f3e15eeca6df2d4bc11c04d9d91c0)

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: api - Introduce crypto_queue_len() helper function

This patch introduces crypto_queue_len() helper function to help to get the
queue length in the crypto queue list now.

Signed-off-by: Baolin Wang <baolin.wang@linaro.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: aead - Convert top level interface to new style

This patch converts the top-level aead interface to the new style.
All user-level AEAD interface code have been moved into crypto/aead.h.

The allocation/free functions have switched over to the new way of
allocating tfms.

This patch also removes the double indrection on setkey so the
indirection now exists only at the alg level.

Apart from these there are no user-visible changes.

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 - 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 - Move crypto_yield() to algapi.h

It makes no sense for crypto_yield() to be defined in scatterwalk.h ,
move it into algapi.h as it's an internal function to crypto API.

Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: allow blkcipher walks over AEAD data

This adds the function blkcipher_aead_walk_virt_block, which allows the caller
to use the blkcipher walk API to handle the input and output scatterlists.

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

crypto: remove direct blkcipher_walk dependency on transform

In order to allow other uses of the blkcipher walk API than the blkcipher
algos themselves, this patch copies some of the transform data members to the
walk struct so the transform is only accessed at walk init time.

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

crypto: crypto_memneq - add equality testing of memory regions w/o timing leaks

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>

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: Add a report function pointer to crypto_type

We add a report function pointer to struct crypto_type. This function
pointer is used from the crypto userspace configuration API to report
crypto algorithms to userspace.

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

crypto: skcipher - Add ablkcipher_walk interfaces

These are akin to the blkcipher_walk helpers.

The main differences in the async variant are:

1) Only physical walking is supported. We can't hold on to
kmap mappings across the async operation to support virtual
ablkcipher_walk operations anyways.

2) Bounce buffers used for async more need to be persistent and
freed at a later point in time when the async op completes.
Therefore we maintain a list of writeback buffers and require
that the ablkcipher_walk user call the 'complete' operation
so we can copy the bounce buffers out to the real buffers and
free up the bounce buffer chunks.

These interfaces will be used by the new Niagara2 crypto driver.

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

crypto: hash - Remove legacy hash/digest code

6941c3a0 disabled compilation of the legacy digest code but didn't
actually remove it. Rectify this. Also, remove the crypto_hash_type
extern declaration from algapi.h now that the struct is gone.

Signed-off-by: Benjamin Gilbert <bgilbert@cs.cmu.edu>
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 aligned ctx helper

The aligned ctx helper was using a bogus alignment value thas was
one off the correct value. Fortunately the current users do not
require anything beyond the natural alignment of the platform so
this hasn't caused a problem.

This patch fixes that and also removes the unnecessary minimum
check since if the alignment is less than the natural alignment
then the subsequent ALIGN operation should be a noop.

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

crypto: cryptd - Switch to template create API

This patch changes cryptd to use the template->create function
instead of alloc in anticipation for the switch to new style
ahash algorithms.

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

crypto: api - Remove frontend argument from extsize/init_tfm

As the extsize and init_tfm functions belong to the frontend the
frontend argument is superfluous.

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 - Add new template create function

This patch introduces the template->create function intended
to replace the existing alloc function. The intention is for
create to handle the registration directly, whereas currently
the caller of alloc has to handle the registration.

This allows type-specific code to be run prior to registration.

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

crypto: hash - Export shash through hash

This patch allows shash algorithms to be used through the old hash
interface. This is a transitional measure so we can convert the
underlying algorithms to shash before converting the users across.

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

crypto: api - Rebirth of crypto_alloc_tfm

This patch reintroduces a completely revamped crypto_alloc_tfm.
The biggest change is that we now take two crypto_type objects
when allocating a tfm, a frontend and a backend. In fact this
simply formalises what we've been doing behind the API's back.

For example, as it stands crypto_alloc_ahash may use an
actual ahash algorithm or a crypto_hash algorithm. Putting
this in the API allows us to do this much more cleanly.

The existing types will be converted across gradually.

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

crypto: api - Move type exit function into crypto_tfm

The type exit function needs to undo any allocations done by the type
init function. However, the type init function may differ depending
on the upper-level type of the transform (e.g., a crypto_blkcipher
instantiated as a crypto_ablkcipher).

So we need to move the exit function out of the lower-level
structure and into crypto_tfm itself.

As it stands this is a no-op since nobody uses exit functions at
all. However, all cases where a lower-level type is instantiated
as a different upper-level type (such as blkcipher as ablkcipher)
will be converted such that they allocate the underlying transform
and use that instead of casting (e.g., crypto_ablkcipher casted
into crypto_blkcipher). That will need to use a different exit
function depending on the upper-level type.

This patch also allows the type init/exit functions to call (or not)
cra_init/cra_exit instead of always calling them from the top level.

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

crypto: hash - Move ahash functions into crypto/hash.h

All new crypto interfaces should go into individual files as much
as possible in order to ensure that crypto.h does not collapse under
its own weight.

This patch moves the ahash code into crypto/hash.h and crypto/internal/hash.h
respectively.

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

[CRYPTO] hash: Add asynchronous hash support

This patch adds asynchronous hash and digest support.

Signed-off-by: Loc Ho <lho@amcc.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] skcipher: Remove crypto_spawn_ablkcipher

Now that gcm and authenc have been converted to crypto_spawn_skcipher,
this patch removes the obsolete crypto_spawn_ablkcipher function.

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

[CRYPTO] skcipher: Add crypto_grab_skcipher interface

Note: From now on the collective of ablkcipher/blkcipher/givcipher will
be known as skcipher, i.e., symmetric key cipher. The name blkcipher has
always been much of a misnomer since it supports stream ciphers too.

This patch adds the function crypto_grab_skcipher as a new way of getting
an ablkcipher spawn. The problem is that previously we did this in two
steps, first getting the algorithm and then calling crypto_init_spawn.

This meant that each spawn user had to be aware of what type and mask to
use for these two steps. This is difficult and also presents a problem
when the type/mask changes as they're about to be for IV generators.

The new interface does both steps together just like crypto_alloc_ablkcipher.

As a side-effect this also allows us to be stronger on type enforcement
for spawns. For now this is only done for ablkcipher but it's trivial
to extend for other types.

This patch also moves the type/mask logic for skcipher into the helpers
crypto_skcipher_type and crypto_skcipher_mask.

Finally this patch introduces the function crypto_require_sync to determine
whether the user is specifically requesting a sync algorithm.

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] ablkcipher: Add distinct ABLKCIPHER type

Up until now we have ablkcipher algorithms have been identified as
type BLKCIPHER with the ASYNC bit set. This is suboptimal because
ablkcipher refers to two things. On the one hand it refers to the
top-level ablkcipher interface with requests. On the other hand it
refers to and algorithm type underneath.

As it is you cannot request a synchronous block cipher algorithm
with the ablkcipher interface on top. This is a problem because
we want to be able to eventually phase out the blkcipher top-level
interface.

This patch fixes this by making ABLKCIPHER its own type, just as
we have distinct types for HASH and DIGEST. The type it associated
with the algorithm implementation only.

Which top-level interface is used for synchronous block ciphers is
then determined by the mask that's used. If it's a specific mask
then the old blkcipher interface is given, otherwise we go with the
new ablkcipher interface.

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

[CRYPTO] blkcipher: Added blkcipher_walk_virt_block

This patch adds the helper blkcipher_walk_virt_block which is similar to
blkcipher_walk_virt but uses a supplied block size instead of the block
size of the block cipher. This is useful for CTR where the block size is
1 but we still want to walk by the block size of the underlying cipher.

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] ablkcipher: Remove queue pointer from common alg object

Since not everyone needs a queue pointer and those who need it can
always get it from the context anyway the queue pointer in the
common alg object is redundant.

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

[CRYPTO] api: Add aead crypto type

This patch adds crypto_aead which is the interface for AEAD
(Authenticated Encryption with Associated Data) algorithms.

AEAD algorithms perform authentication and encryption in one
step. Traditionally users (such as IPsec) would use two
different crypto algorithms to perform these. With AEAD
this comes down to one algorithm and one operation.

Of course if traditional algorithms were used we'd still
be doing two operations underneath. However, real AEAD
algorithms may allow the underlying operations to be
optimised as well.

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

[CRYPTO] api: Add crypto_ablkcipher_ctx_aligned

This is function does the same thing for ablkcipher that is done for
blkcipher by crypto_blkcipher_ctx_aligned(): it returns an aligned
address of the private ctx.

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

[CRYPTO] cryptd: Add software async crypto daemon

This patch adds the cryptd module which is a template that takes a
synchronous software crypto algorithm and converts it to an asynchronous
one by executing it in a kernel thread.

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] digest: Added user API for new hash type

The existing digest user interface is inadequate for support asynchronous
operations. For one it doesn't return a value to indicate success or
failure, nor does it take a per-operation descriptor which is essential
for the issuing of requests while other requests are still outstanding.

This patch is the first in a series of steps to remodel the interface
for asynchronous operations.

For the ease of transition the new interface will be known as "hash"
while the old one will remain as "digest".

This patch also changes sg_next to allow chaining.

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

[CRYPTO] cipher: Added block ciphers for CBC/ECB

This patch adds two block cipher algorithms, CBC and ECB. These
are implemented as templates on top of existing single-block cipher
algorithms. They invoke the single-block cipher through the new
encrypt_one/decrypt_one interface.

This also optimises the in-place encryption and decryption to remove
the cost of an IV copy each round.

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

[CRYPTO] cipher: Added block cipher type

This patch adds the new type of block ciphers. Unlike current cipher
algorithms which operate on a single block at a time, block ciphers
operate on an arbitrarily long linear area of data. As it is block-based,
it will skip any data remaining at the end which cannot form a block.

The block cipher has one major difference when compared to the existing
block cipher implementation. The sg walking is now performed by the
algorithm rather than the cipher mid-layer. This is needed for drivers
that directly support sg lists. It also improves performance for all
algorithms as it reduces the total number of indirect calls by one.

In future the existing cipher algorithm will be converted to only have
a single-block interface. This will be done after all existing users
have switched over to the new block cipher type.

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

[CRYPTO] scatterwalk: Prepare for block ciphers

This patch prepares the scatterwalk code for use by the new block cipher
type.

Firstly it halves the size of scatter_walk on 32-bit platforms. This
is important as we allocate at least two of these objects on the stack
for each block cipher operation.

It also exports the symbols since the block cipher code can be built as
a module.

Finally there is a hack in scatterwalk_unmap that relies on progress
being made. Unfortunately, for hardware crypto we can't guarantee
progress to be made since the hardware can fail.

So this also gets rid of the hack by not advancing the address returned
by scatterwalk_map.

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

[CRYPTO] cipher: Added encrypt_one/decrypt_one

This patch adds two new operations for the simple cipher that encrypts or
decrypts a single block at a time. This will be the main interface after
the existing block operations have moved over to the new block ciphers.

It also adds the crypto_cipher type which is currently only used on the
new operations but will be extended to setkey as well once existing users
have been converted to use block ciphers where applicable.

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

[CRYPTO] api: Added crypto_type support

This patch adds the crypto_type structure which will be used for all new
crypto algorithm types, beginning with block ciphers.

The primary purpose of this abstraction is to allow different crypto_type
objects for crypto algorithms of the same type, in particular, there will
be a different crypto_type objects for asynchronous algorithms.

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: 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>