Pointer esph is being assigned a value that is never read, esph is
re-assigned and only read inside an if statement, hence the
initialization is redundant and can be removed.

Cleans up clang warning:
net/ipv4/esp4.c:657:21: warning: Value stored to 'esph' during
its initialization is never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

Overlapping changes all over.

The mini-qdisc bits were a little bit tricky, however.

Signed-off-by: David S. Miller <davem@davemloft.net>

Currently esp will happily create an xfrm state with an unknown
encap type for IPv4, without setting the necessary state parameters.
This patch fixes it by returning -EINVAL.

There is a similar problem in IPv6 where if the mode is unknown
we will skip initialisation while returning zero.  However, this
is harmless as the mode has already been checked further up the
stack.  This patch removes this anomaly by aligning the IPv6
behaviour with IPv4 and treating unknown modes (which cannot
actually happen) as transport mode.

Fixes: 38320c70d282 ("[IPSEC]: Use crypto_aead and authenc in ESP")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

We support asynchronous crypto on layer 2 ESP now.
So no need to force synchronous crypto fallback on
offloading anymore.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

This patch implements asynchronous crypto callbacks
and a backlog handler that can be used when IPsec
is done at layer 2 in the TX path. It also extends
the skb validate functions so that we can update
the driver transmit return codes based on async
crypto operation or to indicate that we queued the
packet in a backlog queue.

Joint work with: Aviv Heller <avivh@mellanox.com>

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

Replace -EBUSY with -ENOSPC when handling transient busy
indication in the absence of backlog.

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

Three cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>

In conjunction with crypto offload [1], removing the ESP trailer by
hardware can potentially improve the performance by avoiding (1) a
cache miss incurred by reading the nexthdr field and (2) the necessity
to calculate the csum value of the trailer in order to keep skb->csum
valid.

This patch introduces the changes to the xfrm stack and merely serves
as an infrastructure. Subsequent patch to mlx5 driver will put this to
a good use.

[1] https://www.mail-archive.com/netdev@vger.kernel.org/msg175733.html

Signed-off-by: Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

We use skb_availroom to calculate the skb tailroom for the
ESP trailer. skb_availroom calculates the tailroom and
subtracts this value by reserved_tailroom. However
reserved_tailroom is a union with the skb mark. This means
that we subtract the tailroom by the skb mark if set.
Fix this by using skb_tailroom instead.

Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

We allocate the page fragment for the ESP trailer inside
a spinlock, but consume it outside of the lock. This
is racy as some other cou could get the same page fragment
then. Fix this by consuming the page fragment inside the
lock too.

Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>