Merge branch 'net-ktls'

Dave Watson says:

====================
net: kernel TLS

This series adds support for kernel TLS encryption over TCP sockets.
A standard TCP socket is converted to a TLS socket using a setsockopt.
Only symmetric crypto is done in the kernel, as well as TLS record
framing.  The handshake remains in userspace, and the negotiated
cipher keys/iv are provided to the TCP socket.

We implemented support for this API in OpenSSL 1.1.0, the code is
available at https://github.com/Mellanox/tls-openssl/tree/master

It should work with any TLS library with similar modifications,
a test tool using gnutls is here: https://github.com/Mellanox/tls-af_ktls_tool

RFC patch to openssl:
https://mta.openssl.org/pipermail/openssl-dev/2017-June/009384.html

Changes from V2:

* EXPORT_SYMBOL_GPL in patch 1
* Ensure cleanup code always called before sk_stream_kill_queues to
  avoid warnings

Changes from V1:

* EXPORT_SYMBOL GPL in patch 2
* Add link to OpenSSL patch & gnutls example in documentation patch.
* sk_write_pending check was rolled in to wait_for_memory path,
  avoids special case and fixes lock inbalance issue.
* Unify flag handling for sendmsg/sendfile

Changes from RFC V2:

* Generic ULP (upper layer protocol) framework instead of TLS specific
  setsockopts
* Dropped Mellanox hardware patches, will come as separate series.
  Framework will work for both.

RFC V2:

http://www.mail-archive.com/netdev@vger.kernel.org/msg160317.html

Changes from RFC V1:

* Socket based on changing TCP proto_ops instead of crypto framework
* Merged code with Mellanox's hardware tls offload
* Zerocopy sendmsg support added - sendpage/sendfile is no longer
  necessary for zerocopy optimization

RFC V1:

http://www.mail-archive.com/netdev@vger.kernel.org/msg88021.html

* Socket based on crypto userspace API framework, required two
  sockets in userspace, one encrypted, one unencrypted.

Paper: https://netdevconf.org/1.2/papers/ktls.pdf
====================

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