The updated memory management is described in the top part of the code.
As one benefit of the changed memory management, the AIO and synchronous
operation is now implemented in one common function. The AF_ALG
operation uses the async kernel crypto API interface for each cipher
operation. Thus, the only difference between the AIO and sync operation
types visible from user space is:

1. the callback function to be invoked when the asynchronous operation
   is completed

2. whether to wait for the completion of the kernel crypto API operation
   or not

The change includes the overhaul of the TX and RX SGL handling. The TX
SGL holding the data sent from user space to the kernel is now dynamic
similar to algif_skcipher. This dynamic nature allows a continuous
operation of a thread sending data and a second thread receiving the
data. These threads do not need to synchronize as the kernel processes
as much data from the TX SGL to fill the RX SGL.

The caller reading the data from the kernel defines the amount of data
to be processed. Considering that the interface covers AEAD
authenticating ciphers, the reader must provide the buffer in the
correct size. Thus the reader defines the encryption size.
Signed-off-by: NStephan Mueller <smueller@chronox.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

This patch uses refcount_inc_not_zero() instead of
atomic_inc_not_zero_hint() due to absense of a _hint()
version of refcount API. If the hint() version must
be used, we might need to revisit API.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some cipher implementations will crash if you try to use them
without calling setkey first.  This patch adds a check so that
the accept(2) call will fail with -ENOKEY if setkey hasn't been
done on the socket yet.

Fixes: 400c40cf ("crypto: algif - add AEAD support")
Cc: <stable@vger.kernel.org>
Signed-off-by: NStephan Mueller <smueller@chronox.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

The algif_aead completion function tries to deduce the aead_request
from the crypto_async_request argument.  This is broken because
the API does not guarantee that the same request will be pased to
the completion function.  Only the value of req->data can be used
in the completion function.

This patch fixes it by storing a pointer to sk in areq and using
that instead of passing in sk through req->data.

Fixes: 83094e5e ("crypto: af_alg - add async support to...")
Cc: <stable@vger.kernel.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>

Fix up affected files that include this signal functionality via sched.h.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Kernel panics when userspace program try to access AEAD interface.
Remove node from Linked List before freeing its memory.

Cc: <stable@vger.kernel.org>
Signed-off-by: NHarsh Jain <harsh@chelsio.com>
Reviewed-by: NStephan Müller <smueller@chronox.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

The previous description have been misleading and partially incorrect.
Reported-by: NHarsh Jain <harshjain.prof@gmail.com>
Signed-off-by: NStephan Mueller <smueller@chronox.de>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

In case the user provided insufficient data, the code may return
prematurely without any operation. In this case, the processed
data indicated with outlen is zero.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NStephan Mueller <smueller@chronox.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

For encryption, the AEAD ciphers require AAD || PT as input and generate
AAD || CT || Tag as output and vice versa for decryption. Prior to this
patch, the AF_ALG interface for AEAD ciphers requires the buffer to be
present as input for encryption. Similarly, the output buffer for
decryption required the presence of the tag buffer too. This implies
that the kernel reads / writes data buffers from/to kernel space
even though this operation is not required.

This patch changes the AF_ALG AEAD interface to be consistent with the
in-kernel AEAD cipher requirements.

Due to this handling, he changes are transparent to user space with one
exception: the return code of recv indicates the mount of output buffer.
That output buffer has a different size compared to before the patch
which implies that the return code of recv will also be different.
For example, a decryption operation uses 16 bytes AAD, 16 bytes CT and
16 bytes tag, the AF_ALG AEAD interface before showed a recv return
code of 48 (bytes) whereas after this patch, the return code is 32
since the tag is not returned any more.
Reported-by: NMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: NStephan Mueller <smueller@chronox.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Handle the case when the caller provided a zero buffer to
sendmsg/sendpage. Such scenario is legal for AEAD ciphers when no
plaintext / ciphertext and no AAD is provided and the caller only
requests the generation of the tag value.
Signed-off-by: NStephan Mueller <smueller@chronox.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Similar to commit 14135f30 ("inet: fix sleeping inside inet_wait_for_connect()"),
sk_wait_event() needs to fix too, because release_sock() is blocking,
it changes the process state back to running after sleep, which breaks
the previous prepare_to_wait().

Switch to the new wait API.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Following the async change for algif_skcipher
this patch adds similar async read to algif_aead.

changes in v3:
- add call to aead_reset_ctx directly from aead_put_sgl instead of calling
  them separatelly one after the other
- remove wait from aead_sock_destruct function as it is not needed
  when sock_hold is used

changes in v2:
- change internal data structures from fixed size arrays, limited to
  RSGL_MAX_ENTRIES, to linked list model with no artificial limitation.
- use sock_kmalloc instead of kmalloc for memory allocation
- use sock_hold instead of separate atomic ctr to wait for outstanding
  request
Signed-off-by: NTadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch is a cleanup to make following patch easier to
review.

Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
from (struct socket)->flags to a (struct socket_wq)->flags
to benefit from RCU protection in sock_wake_async()

To ease backports, we rename both constants.

Two new helpers, sk_set_bit(int nr, struct sock *sk)
and sk_clear_bit(int net, struct sock *sk) are added so that
following patch can change their implementation.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The memory barrier in the helper wq_has_sleeper is needed by just
about every user of waitqueue_active.  This patch generalises it
by making it take a wait_queue_head_t directly.  The existing
helper is renamed to skwq_has_sleeper.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some variable are set as int but store only positive values.
Furthermore there are used in operation/function that wait for unsigned
value.
This patch set them as size_t.
Signed-off-by: NLABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

The tsgl scatterlist must be re-initialized after each
operation. Otherwise the sticky bits in the page_link will corrupt the
list with pre-mature termination or false chaining.
Signed-off-by: NLars Persson <larper@axis.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch removes the CRYPTO_ALG_AEAD_NEW flag now that everyone
has been converted.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

As the AEAD conversion is still ongoing, we do not yet wish to
export legacy AEAD implementations to user-space, as their calling
convention will change.

This patch actually disables all AEAD algorithms because some of
them (e.g., cryptd) will need to be modified to propagate this flag.

Subsequent patches will reenable them on an individual basis.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch makes use of the new AEAD interface which uses a single
SG list instead of separate lists for the AD and plain text.

Note that the user-space interface now requires both input and
output to be of the same length, and both must include space for
the AD as well as the authentication tag.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch fixes it.
Also minor updates to comments.
Signed-off-by: NTadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

All users of AEAD should include crypto/aead.h instead of
include/linux/crypto.h.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Acked-by: NDavid S. Miller <davem@davemloft.net>

The networking updates from David Miller removed the iocb argument from
sendmsg and recvmsg (in commit 1b784140: "net: Remove iocb argument
from sendmsg and recvmsg"), but the crypto code had added new instances
of them.

When I pulled the crypto update, it was a silent semantic mis-merge, and
I overlooked the new warning messages in my test-build.  I try to fix
those in the merge itself, but that relies on me noticing. Oh well.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adds the AEAD support for AF_ALG.

The implementation is based on algif_skcipher, but contains heavy
modifications to streamline the interface for AEAD uses.

To use AEAD, the user space consumer has to use the salg_type named
"aead".

The AEAD implementation includes some overhead to calculate the size of
the ciphertext, because the AEAD implementation of the kernel crypto API
makes implied assumption on the location of the authentication tag. When
performing an encryption, the tag will be added to the created
ciphertext (note, the tag is placed adjacent to the ciphertext). For
decryption, the caller must hand in the ciphertext with the tag appended
to the ciphertext. Therefore, the selection of the used memory
needs to add/subtract the tag size from the source/destination buffers
depending on the encryption type. The code is provided with comments
explaining when and how that operation is performed.

A fully working example using all aspects of AEAD is provided at
http://www.chronox.de/libkcapi.htmlSigned-off-by: NStephan Mueller <smueller@chronox.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>