Re: [PATCH net-next v2] selftests/net/openvswitch: add SCTP flow key test

[Ilya Maximets <i.maximets@ovn.org>]

On 7/7/26 5:47 AM, Minxi Hou wrote:
> Register OVS_KEY_ATTR_SCTP in the flow key parser so that sctp()
> can be used in flow specifications. The ovs_key_sctp class already
> exists (with src/dst fields matching the TCP/UDP siblings) but was
> not wired into the parser, so the token was silently dropped and the
> kernel rejected the flow.
> 
> Add test_sctp_connect_v4 exercising the SCTP flow key with
> port-specific matching: sctp(dst=4443) for client-to-server and
> sctp(src=4443) for server-to-client.
> 
> Wait for ncat readiness with ovs_wait instead of a fixed sleep so
> the test does not race against ncat startup. Use grep -c on the
> listening message to distinguish between successive ncat instances
> that share the same stderr log. Kill the previous server before
> respawning to avoid EADDRINUSE on the SCTP port.
> 
> Signed-off-by: Minxi Hou <houminxi@gmail.com>
> ---
> v1 -> v2: replace sleep with ovs_wait on ncat listening output,
>           kill previous ncat server before respawning to avoid
>           port conflict (Aaron review feedback)
> 
>  .../selftests/net/openvswitch/openvswitch.sh  | 102 ++++++++++++++++++
>  .../selftests/net/openvswitch/ovs-dpctl.py    |   5 +
>  2 files changed, 107 insertions(+)
> 
> diff --git a/tools/testing/selftests/net/openvswitch/openvswitch.sh b/tools/testing/selftests/net/openvswitch/openvswitch.sh
> index 2954245129a2..9c364eeb2ec2 100755
> --- a/tools/testing/selftests/net/openvswitch/openvswitch.sh
> +++ b/tools/testing/selftests/net/openvswitch/openvswitch.sh
> @@ -32,6 +32,7 @@ tests="
>  	dec_ttl					ttl: dec_ttl decrements IP TTL
>  	flow_set				flow-set: Flow modify
>  	action_set				set: SET action rewrites fields
> +	sctp_connect_v4				sctp: SCTP flow key matching
>  	psample					psample: Sampling packets with psample"
>  
>  info() {
> @@ -443,6 +444,107 @@ test_action_set() {
>  	return 0
>  }
>  
> +# sctp_connect_v4 test
> +# - sctp(dst=4443) matches client-to-server INIT
> +# - sctp(src=4443) matches server-to-client INIT-ACK
> +# - remove flows and verify connection fails, reinstall and recover
> +test_sctp_connect_v4() {
> +	local t="test_sctp_connect_v4"
> +
> +	which ncat >/dev/null 2>&1 || return $ksft_skip

Not a full review, but can we avoid ncat?  We already use nc in other
tests, using different implementations of the same thing in different
tests doesn't sound like a good idea.  On mnay systems nc and ncat
will be different implementations with different options and behavior.

Best regards, Ilya Maximets.