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Date:   Wed, 24 Aug 2022 14:46:32 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Leonard Crestez <cdleonard@gmail.com>
Cc:     Dmitry Safonov <dima@arista.com>, David Ahern <dsahern@kernel.org>,
        Andy Lutomirski <luto@amacapital.net>,
        Ard Biesheuvel <ardb@kernel.org>,
        Bob Gilligan <gilligan@arista.com>,
        Dmitry Safonov <0x7f454c46@gmail.com>,
        Eric Biggers <ebiggers@kernel.org>,
        Francesco Ruggeri <fruggeri@arista.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Ivan Delalande <colona@arista.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Salam Noureddine <noureddine@arista.com>,
        Shuah Khan <shuah@kernel.org>, netdev@vger.kernel.org,
        linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>
Subject: Re: [PATCH 00/31] net/tcp: Add TCP-AO support
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> I think it would make sense to push key validity times and the key selection
> policy entirely in the kernel so that it can handle key rotation/expiration
> by itself. This way userspace only has to configure the keys and doesn't
> have to touch established connections at all.

I know nothing aobut TCP-AO, nor much about kTLS. But doesn't kTLS
have the same issue? Is there anything which can be learnt from kTLS?
Maybe the same mechanisms can be used? No point inventing something
new if you can copy/refactor working code?

> My series has a "flags" field on the key struct where it can filter by IP,
> prefix, ifindex and so on. It would be possible to add additional flags for
> making the key only valid between certain times (by wall time).

What out for wall clock time, it jumps around in funny ways. Plus the
kernel has no idea what time zone the wall the wall clock is mounted
on is in.

    Andrew