selftests: forwarding: Fix layer 2 miss test flakiness

After enabling a multicast querier on the bridge (like the test is
doing), the bridge will wait for the Max Response Delay before starting
to forward according to its MDB in order to let Membership Reports
enough time to be received and processed.

Currently, the test is waiting for exactly the default Max Response
Delay (10 seconds) which is racy and leads to failures [1].

Fix by reducing the Max Response Delay to 1 second.

[1]
[...]
# TEST: L2 miss - Multicast (IPv4) [FAIL]
# Unregistered multicast filter was hit after adding MDB entry

Fixes: 8c33266ae26a ("selftests: forwarding: Add layer 2 miss test cases")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20240208155529.1199729-2-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: forwarding: tc_flower_l2_miss: Fix failing test with old libnet

As explained in commit 8bcfb4ae4d97 ("selftests: forwarding: Fix failing
tests with old libnet"), old versions of libnet (used by mausezahn) do
not use the "SO_BINDTODEVICE" socket option. For IP unicast packets,
this can be solved by prefixing mausezahn invocations with "ip vrf
exec". However, IP multicast packets do not perform routing and simply
egress the bound device, which does not exist in this case.

Fix by specifying the source and destination MAC of the packet which
will cause mausezahn to use a packet socket instead of an IP socket.

Fixes: 8c33266ae26a ("selftests: forwarding: Add layer 2 miss test cases")
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Closes: https://lore.kernel.org/netdev/adc5e40d-d040-a65e-eb26-edf47dac5b02@alu.unizg.hr/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230808141503.4060661-15-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: forwarding: Fix layer 2 miss test syntax

The test currently specifies "l2_miss" as "true" / "false", but the
version that eventually landed in iproute2 uses "1" / "0" [1]. Align the
test accordingly.

[1] https://lore.kernel.org/netdev/20230607153550.3829340-1-idosch@nvidia.com/

Fixes: 8c33266ae26a ("selftests: forwarding: Add layer 2 miss test cases")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: forwarding: Add layer 2 miss test cases

Add test cases to verify that the bridge driver correctly marks layer 2
misses only when it should and that the flower classifier can match on
this metadata.

Example output:

# ./tc_flower_l2_miss.sh
TEST: L2 miss - Unicast [ OK ]
TEST: L2 miss - Multicast (IPv4) [ OK ]
TEST: L2 miss - Multicast (IPv6) [ OK ]
TEST: L2 miss - Link-local multicast (IPv4) [ OK ]
TEST: L2 miss - Link-local multicast (IPv6) [ OK ]
TEST: L2 miss - Broadcast [ OK ]

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>