topotests: add static mpls routing test

There is no test that checks for the mpls interface
configuration.
The new test checks that mpls configuration per
interface works when value is enabled or disabled.

Signed-off-by: Philippe Guibert <[email protected]>

tests/topotests/static_routing_mpls/r1/zebra.conf

@@ -0,0 +1,16 @@
+hostname r1
+ip forwarding
+ipv6 forwarding
+
+int r1-eth0
+  ip addr 192.168.1.1/24
+!
+int r1-eth1
+  ip addr 192.168.2.1/24
+!
+int lo
+  ip addr 192.0.2.1/32
+!
+int r1-eth1
+  ip addr 192.168.2.1/24
+!

tests/topotests/static_routing_mpls/r2/zebra.conf

@@ -0,0 +1,18 @@
+hostname r2
+ip forwarding
+ipv6 forwarding
+
+int r2-eth0
+  ip addr 192.168.2.2/24
+!
+int r2-eth1
+  mpls enable
+  ip addr 192.168.3.2/24
+!
+int r2-eth2
+  mpls disable
+  ip addr 172.31.3.2/24
+!
+int lo
+  ip addr 192.0.2.2/32
+!

tests/topotests/static_routing_mpls/test_static_routing_mpls.py

@@ -0,0 +1,139 @@
+#!/usr/bin/env python
+# SPDX-License-Identifier: ISC
+
+#
+# test_static_routing_mlpls.py
+# Part of NetDEF Topology Tests
+#
+# Copyright (c) 2023 by 6WIND
+#
+
+"""
+test_static_routing_mpls.py: Testing MPLS configuration with mpls interface settings
+
+"""
+
+import os
+import re
+import sys
+import pytest
+import json
+from functools import partial
+import functools
+
+# Save the Current Working Directory to find configuration files.
+CWD = os.path.dirname(os.path.realpath(__file__))
+sys.path.append(os.path.join(CWD, "../"))
+
+# pylint: disable=C0413
+# Import topogen and topotest helpers
+from lib import topotest
+from lib.topogen import Topogen, TopoRouter, get_topogen
+from lib.topolog import logger
+
+# Required to instantiate the topology builder class.
+
+#####################################################
+##
+##   Network Topology Definition
+##
+#####################################################
+
+
+def build_topo(tgen):
+    "Build function"
+
+    tgen.add_router("r1")
+    tgen.add_router("r2")
+
+    switch = tgen.add_switch("sw1")
+    switch.add_link(tgen.gears["r1"])
+
+    switch = tgen.add_switch("sw2")
+    switch.add_link(tgen.gears["r1"])
+    switch.add_link(tgen.gears["r2"])
+
+    switch = tgen.add_switch("sw3")
+    switch.add_link(tgen.gears["r2"])
+
+    switch = tgen.add_switch("sw4")
+    switch.add_link(tgen.gears["r2"])
+
+
+#####################################################
+##
+##   Tests starting
+##
+#####################################################
+def _populate_mpls_labels():
+    tgen = get_topogen()
+    cmds_list = ["echo 100000 > /proc/sys/net/mpls/platform_labels"]
+    for cmd in cmds_list:
+        for host in ("r1", "r2"):
+            logger.info("input: " + cmd)
+            output = tgen.net[host].cmd(cmd)
+            logger.info("output: " + output)
+
+
+def setup_module(module):
+    "Setup topology"
+    tgen = Topogen(build_topo, module.__name__)
+    tgen.start_topology()
+
+    _populate_mpls_labels()
+
+    # This is a sample of configuration loading.
+    router_list = tgen.routers()
+    for rname, router in router_list.items():
+        router.load_config(
+            TopoRouter.RD_ZEBRA, os.path.join(CWD, "{}/zebra.conf".format(rname))
+        )
+
+    tgen.start_router()
+
+
+def teardown_module(_mod):
+    "Teardown the pytest environment"
+    tgen = get_topogen()
+
+    # This function tears down the whole topology.
+    tgen.stop_topology()
+
+
+def _check_mpls_state_interface(router, interface, up=True):
+    output = router.vtysh_cmd("show interface {}".format(interface))
+    if up and "MPLS enabled" in output:
+        return None
+    elif not up and "MPLS enabled" not in output:
+        return None
+    return "not good"
+
+
+def _check_mpls_state(router, interface, configured=True):
+    test_func = functools.partial(
+        _check_mpls_state_interface, router, interface, up=configured
+    )
+    success, result = topotest.run_and_expect(test_func, None, count=10, wait=0.5)
+    return success
+
+
+def test_mpls_configured_on_interface():
+    "Test 'mpls' state is correctly configured on an unconfigured interfaces"
+
+    tgen = get_topogen()
+    # Don't run this test if we have any failure.
+    if tgen.routers_have_failure():
+        pytest.skip(tgen.errors)
+
+    logger.info("Checking that MPLS state is on on r2-eth1")
+    assertmsg = "r2, interface r2-eth1, mpls operational state is off, not expected"
+    assert _check_mpls_state(tgen.gears["r2"], "r2-eth1"), assertmsg
+
+    logger.info("Checking that MPLS state is off on r2-eth2")
+    assertmsg = "r2, interface r2-eth2, mpls operational state is on, not expected"
+    assert _check_mpls_state(tgen.gears["r2"], "r2-eth2", False), assertmsg
+
+
+if __name__ == "__main__":
+    args = ["-s"] + sys.argv[1:]
+    sys.exit(pytest.main(args))