[PATCH net-next v5 4/6] tls: update the RX key when a KeyUpdate is received

[Hannes Reinecke]

On 11/3/26 10:43 PM, Martin Belanger via B4 Relay wrote:
> From: Martin Belanger <martin.belanger at dell.com>
> 
> When a KeyUpdate arrives, kTLS blocks reads with -EKEYEXPIRED until
> the user installs the next key. A kernel user such as nvme-tcp or
> sunrpc never does, so the connection stalls.
> 
> For a socket with a registered RX secret, derive the next key and
> install it when the KeyUpdate is decrypted. The record is not passed to
> the user, so recvmsg(), splice() and read_sock() go on to the next
> record. Without a registered secret the behavior is unchanged.
> 
> A KeyUpdate that is not alone in its record, has a wrong length or an
> invalid request_update value ends the connection, as RFC 9846 section
> 4.7.3 requires. So does a peer that sends more than 8 KeyUpdates in one
> second, the same limit as GnuTLS. That case is counted as
> TlsRxRekeyError and logged, rate limited.
> 
> Reviewed-by: Chuck Lever <cel at kernel.org>
> Signed-off-by: Martin Belanger <martin.belanger at dell.com>
> ---
>   include/net/tls.h       |   7 +++
>   net/tls/Makefile        |   3 +-
>   net/tls/tls.h           |   2 +
>   net/tls/tls_keyupdate.c | 155 ++++++++++++++++++++++++++++++++++++++++++++++++
>   net/tls/tls_sw.c        |  38 +++++++++++-
>   5 files changed, 201 insertions(+), 4 deletions(-)
> 
Reviewed-by: Hannes Reinecke <hare at kernel.org>

Cheerx,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare at suse.de                                +49 911 74053 688
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