[PATCH 0/8] nvme-tcp: Support receiving KeyUpdate requests

[alistair23 at gmail.com]

From: Alistair Francis <alistair.francis at wdc.com>

The TLS 1.3 specification allows the TLS client or server to send a
KeyUpdate. This is generally used when the sequence is about to
overflow or after a certain amount of bytes have been encrypted.

The TLS spec doesn't mandate the conditions though, so a KeyUpdate
can be sent by the TLS client or server at any time. This includes
when running NVMe-OF over a TLS 1.3 connection.

As such Linux should be able to handle a KeyUpdate event, as the
other NVMe side could initiate a KeyUpdate.

Upcoming WD NVMe-TCP hardware controllers implement TLS support
and send KeyUpdate requests.

This series builds on top of the existing TLS EKEYEXPIRED work,
which already detects a KeyUpdate request. We can now pass that
information up to the NVMe layer (target and host) and then pass
it up to userspace.

Userspace (ktls-utils) will need to save the connection state
in the keyring during the initial handshake. The kernel then
provides the key serial back to userspace when handling a
KeyUpdate. Userspace can use this to restore the connection
information and then update the keys, this final process
is similar to the initial handshake.

Link: https://datatracker.ietf.org/doc/html/rfc8446#section-4.6.3

Alistair Francis (8):
  net/handshake: Store the key serial number on completion
  net/handshake: Make handshake_req_cancel public
  net/handshake: Expose handshake_sk_destruct_req publically
  tls: Allow callers to clear errors
  net/handshake: Support KeyUpdate message types
  nvme-tcp: Support KeyUpdate
  net/handshake: Support decoding the HandshakeType
  nvmet-tcp: Support KeyUpdate

 Documentation/netlink/specs/handshake.yaml | 19 +++++-
 Documentation/networking/tls-handshake.rst |  4 +-
 drivers/nvme/host/tcp.c                    | 78 ++++++++++++++++++++--
 drivers/nvme/target/tcp.c                  | 71 ++++++++++++++++++--
 include/net/handshake.h                    | 18 ++++-
 include/net/tls.h                          |  6 ++
 include/net/tls_prot.h                     | 17 +++++
 include/uapi/linux/handshake.h             | 14 ++++
 net/handshake/alert.c                      | 26 ++++++++
 net/handshake/genl.c                       |  5 +-
 net/handshake/handshake-test.c             |  1 +
 net/handshake/handshake.h                  |  1 -
 net/handshake/request.c                    | 17 +++++
 net/handshake/tlshd.c                      | 46 +++++++++++--
 net/sunrpc/svcsock.c                       |  3 +-
 net/sunrpc/xprtsock.c                      |  3 +-
 16 files changed, 300 insertions(+), 29 deletions(-)

-- 
2.50.1