selftests: openvswitch: Fix escape chars in regexp.

Character sequences starting with `\` are interpreted by python as
escaped Unicode characters. However, they have other meaning in
regular expressions (e.g: "\d").

It seems Python >= 3.12 starts emitting a SyntaxWarning when these
escaped sequences are not recognized as valid Unicode characters.

An example of these warnings:

tools/testing/selftests/net/openvswitch/ovs-dpctl.py:505:
SyntaxWarning: invalid escape sequence '\d'

Fix all the warnings by flagging literals as raw strings.

Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Link: https://lore.kernel.org/r/20240416090913.2028475-1-amorenoz@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: openvswitch: Add validation for the recursion test

Add a test case into the netlink checks that will show the number of
nested action recursions won't exceed 16. Going to 17 on a small
clone call isn't enough to exhaust the stack on (most) systems, so
it should be safe to run even on systems that don't have the fix
applied.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240207132416.1488485-3-aconole@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: openvswitch: Fix the ct_tuple for v4

The ct_tuple v4 data structure decode / encode routines were using
the v6 IP address decode and relying on default encode. This could
cause exceptions during encode / decode depending on how a ct4
tuple would appear in a netlink message.

Caught during code review.

Fixes: e52b07aa1a54 ("selftests: openvswitch: add flow dump support")
Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: openvswitch: Skip drop testing on older kernels

Kernels that don't have support for openvswitch drop reasons also
won't have the drop counter reasons, so we should skip the test
completely. It previously wasn't possible to build a test case
for this without polluting the datapath, so we introduce a mechanism
to clear all the flows from a datapath allowing us to test for
explicit drop actions, and then clear the flows to build the
original test case.

Fixes: 4242029164d6 ("selftests: openvswitch: add explicit drop testcase")
Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: openvswitch: Add version check for pyroute2

Paolo Abeni reports that on some systems the pyroute2 version isn't
new enough to run the test suite. Ensure that we support a minimum
version of 0.6 for all cases (which does include the existing ones).
The 0.6.1 version was released in May of 2021, so should be
propagated to most installations at this point.

The alternative that Paolo proposed was to only skip when the
add-flow is being run. This would be okay for most cases, except
if a future test case is added that needs to do flow dump without
an associated add (just guessing). In that case, it could also be
broken and we would need additional skip logic anyway. Just draw
a line in the sand now.

Fixes: 25f16c873fb1 ("selftests: add openvswitch selftest suite")
Reported-by: Paolo Abeni <pabeni@redhat.com>
Closes: https://lore.kernel.org/lkml/8470c431e0930d2ea204a9363a60937289b7fdbe.camel@redhat.com/
Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: openvswitch: add explicit drop action

From: Eric Garver <eric@garver.life>

This adds an explicit drop action. This is used by OVS to drop packets
for which it cannot determine what to do. An explicit action in the
kernel allows passing the reason _why_ the packet is being dropped or
zero to indicate no particular error happened (i.e: OVS intentionally
dropped the packet).

Since the error codes coming from userspace mean nothing for the kernel,
we squash all of them into only two drop reasons:
- OVS_DROP_EXPLICIT_WITH_ERROR to indicate a non-zero value was passed
- OVS_DROP_EXPLICIT to indicate a zero value was passed (no error)

e.g. trace all OVS dropped skbs

# perf trace -e skb:kfree_skb --filter="reason >= 0x30000"
[..]
106.023 ping/2465 skb:kfree_skb(skbaddr: 0xffffa0e8765f2000, \
location:0xffffffffc0d9b462, protocol: 2048, reason: 196611)

reason: 196611 --> 0x30003 (OVS_DROP_EXPLICIT)

Also, this patch allows ovs-dpctl.py to add explicit drop actions as:
"drop" -> implicit empty-action drop
"drop(0)" -> explicit non-error action drop
"drop(42)" -> explicit error action drop

Signed-off-by: Eric Garver <eric@garver.life>
Co-developed-by: Adrian Moreno <amorenoz@redhat.com>
Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: openvswitch: add ct-nat test case with ipv4

Building on the previous work, add a very simplistic NAT case
using ipv4. This just tests dnat transformation

Signed-off-by: Aaron Conole <aconole@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

selftests: openvswitch: add basic ct test case parsing

Forwarding via ct() action is an important use case for openvswitch, but
generally would require using a full ovs-vswitchd to get working. Add a
ct action parser for basic ct test case.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Reviewed-by: Adrian Moreno <amorenoz@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

selftests: openvswitch: support key masks

The default value for the mask actually depends on the value (e.g: if
the value is non-null, the default is full-mask), so change the convert
functions to accept the full, possibly masked string and let them figure
out how to parse the different values.

Also, implement size-aware int parsing.

With this patch we can now express flows such as the following:
"eth(src=0a:ca:fe:ca:fe:0a/ff:ff:00:00:ff:00)"
"eth(src=0a:ca:fe:ca:fe:0a)" -> mask = ff:ff:ff:ff:ff:ff
"ipv4(src=192.168.1.1)" -> mask = 255.255.255.255
"ipv4(src=192.168.1.1/24)"
"ipv4(src=192.168.1.1/255.255.255.0)"
"tcp(src=8080)" -> mask = 0xffff
"tcp(src=8080/0xf0f0)"

Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Acked-by: Aaron Conole <aconole@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

selftests: openvswitch: add an initial flow programming case

The openvswitch self-tests can test much of the control side of
the module (ie: what a vswitchd implementation would process),
but the actual packet forwarding cases aren't supported, making
the testing of limited value.

Add some flow parsing and an initial ARP based test case using
arping utility. This lets us display flows, add some basic
output flows with simple matches, and test against a known good
forwarding case.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Reviewed-by: Adrian Moreno <amorenoz@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

selftests: openvswitch: add support for upcall testing

The upcall socket interface can be exercised now to make sure that
future feature adjustments to the field can maintain backwards
compatibility.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: openvswitch: add flow dump support

Add a basic set of fields to print in a 'dpflow' format. This will be
used by future commits to check for flow fields after parsing, as
well as verifying the flow fields pushed into the kernel from
userspace.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: openvswitch: add interface support

Includes an associated test to generate netns and connect
interfaces, with the option to include packet tracing.

This will be used in the future when flow support is added
for additional test cases.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: openvswitch: adjust datapath NL message declaration

The netlink message for creating a new datapath takes an array
of ports for the PID creation. This shouldn't cause much issue
but correct it for future cases where we need to do decode of
datapath information that could include the per-cpu PID map.

Fixes: 25f16c873fb1 ("selftests: add openvswitch selftest suite")
Signed-off-by: Aaron Conole <aconole@redhat.com>
Link: https://lore.kernel.org/r/20230412115828.3991806-1-aconole@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: add openvswitch selftest suite

Previous commit resolves a WARN splat that can be difficult to reproduce,
but with the ovs-dpctl.py utility, it can be trivial. Introduce a test
case which creates a DP, and then downgrades the feature set. This will
include a utility 'ovs-dpctl.py' that can be extended to do additional
tests and diagnostics.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>