Merge branch 'net-tls-add-socket-diag'

Davide Caratti says:

====================
net: tls: add socket diag

The current kernel does not provide any diagnostic tool, except
getsockopt(TCP_ULP), to know more about TCP sockets that have an upper
layer protocol (ULP) on top of them. This series extends the set of
information exported by INET_DIAG_INFO, to include data that are
specific to the ULP (and that might be meaningful for debug/testing
purposes).

patch 1/3 ensures that the control plane reads/updates ULP specific data
using RCU.

patch 2/3 extends INET_DIAG_INFO and allows knowing the ULP name for
each TCP socket that has done setsockopt(TCP_ULP) successfully.

patch 3/3 extends kTLS to let programs like 'ss' know the protocol
version and the cipher in use.

Changes since v2:
- remove unneeded #ifdef and fix reverse christmas tree in
  tls_get_info(), thanks to Jakub Kicinski

Changes since v1:
- don't worry about grace period when accessing ulp_ops, thanks to
  Jakub Kicinski and Eric Dumazet
- use rcu_dereference() to access ULP data in tls get_info(), and
  test against NULL value, thanks to Jakub Kicinski
- move RCU protected section inside tls get_info(), thanks to Jakub
  Kicinski

Changes since RFC:
- some coding style fixes, thanks to Jakub Kicinski
- add X_UNSPEC as lowest value of uAPI enums, thanks to Jakub Kicinski
- fix assignment of struct nlattr *start, thanks to Jakub Kicinski
- let tls dump RXCONF and TXCONF, suggested by Jakub Kicinski
- don't dump anything if TLS version or cipher are 0 (but still return a
  constant size in get_aux_size()), thanks to Boris Pismenny
- constify first argument of get_info() and get_size()
- use RCU to access access ulp_ops, like it's done for ca_ops
- add patch 1/3, from Jakub Kicinski
====================

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