vpp: T9062: Enable DHCP/DHCPv6 client detection on VLAN sub-interfaces

The 'ip4-dhcp-client-detect' and 'ip6-icmp-ra-punt' VPP features were only
ever enabled on the base ethernet interface, so DHCP and DHCPv6 clients
never worked on VLAN sub-interfaces (vif/vif-s) of a VPP-managed interface.
Apply the same feature toggles to each vif/vif-s using its own address
configuration. vif-c is intentionally excluded, as Q-in-Q sub-interfaces
are not currently functional under VPP.

2 files changed, 79 insertions, 14 deletions

diff --git a/smoketest/scripts/cli/test_vpp.py b/smoketest/scripts/cli/test_vpp.py
index 7813dfdf5..35150a74a 100755
--- a/smoketest/scripts/cli/test_vpp.py
+++ b/smoketest/scripts/cli/test_vpp.py
@@ -210,6 +210,59 @@ class TestVPP(VyOSUnitTestSHIM.TestCase):
             )
             self.assertTrue(icmpv6_ra_punt_feature.is_enabled)
 
+        # DHCP/DHCPv6 must also work on VLAN sub-interfaces
+        vlan = '10'
+        vif_interface = f'{interface}.{vlan}'
+        self.cli_set(
+            ['interfaces', 'ethernet', interface, 'vif', vlan, 'address', 'dhcp']
+        )
+        self.cli_set(
+            ['interfaces', 'ethernet', interface, 'vif', vlan, 'address', 'dhcpv6']
+        )
+        self.cli_commit()
+
+        # check 'ip4-dhcp-client-detect' feature is enabled
+        vif_client_detect_feature = vpp.api.feature_is_enabled(
+            sw_if_index=vpp.get_sw_if_index(vif_interface),
+            feature_name='ip4-dhcp-client-detect',
+            arc_name='ip4-unicast',
+        )
+        self.assertTrue(vif_client_detect_feature.is_enabled)
+
+        # check 'ip6-icmp-ra-punt' feature is enabled
+        # for ip6-unicast and ip6-multicast arcs
+        for arc_name in ['ip6-unicast', 'ip6-multicast']:
+            vif_icmpv6_ra_punt_feature = vpp.api.feature_is_enabled(
+                sw_if_index=vpp.get_sw_if_index(vif_interface),
+                feature_name='ip6-icmp-ra-punt',
+                arc_name=arc_name,
+            )
+            self.assertTrue(vif_icmpv6_ra_punt_feature.is_enabled)
+
+        # remove DHCP/DHCPv6 from the VLAN sub-interface
+        self.cli_delete(['interfaces', 'ethernet', interface, 'vif', vlan, 'address'])
+        self.cli_commit()
+
+        # check 'ip4-dhcp-client-detect' feature is disabled
+        vif_client_detect_feature = vpp.api.feature_is_enabled(
+            sw_if_index=vpp.get_sw_if_index(vif_interface),
+            feature_name='ip4-dhcp-client-detect',
+            arc_name='ip4-unicast',
+        )
+        self.assertFalse(vif_client_detect_feature.is_enabled)
+
+        # check 'ip6-icmp-ra-punt' feature is disabled
+        for arc_name in ['ip6-unicast', 'ip6-multicast']:
+            vif_icmpv6_ra_punt_feature = vpp.api.feature_is_enabled(
+                sw_if_index=vpp.get_sw_if_index(vif_interface),
+                feature_name='ip6-icmp-ra-punt',
+                arc_name=arc_name,
+            )
+            self.assertFalse(vif_icmpv6_ra_punt_feature.is_enabled)
+
+        # cleanup: delete the VLAN sub-interface
+        self.cli_delete(['interfaces', 'ethernet', interface, 'vif', vlan])
+
     def test_02_vpp_vxlan(self):
         vxlan_path = interfaces_path + ['vxlan']
         vni = '23'
diff --git a/src/conf_mode/interfaces_ethernet.py b/src/conf_mode/interfaces_ethernet.py
index 1368f2c6e..40b7843be 100755
--- a/src/conf_mode/interfaces_ethernet.py
+++ b/src/conf_mode/interfaces_ethernet.py
@@ -455,20 +455,32 @@ def apply(ethernet):
     if vpp_iface_config is not None and is_systemd_service_running('vpp.service'):
         vpp_api = VPPControl()
 
-        # Enable ip4-dhcp-client-detect feature for DHCP-configured interfaces.
-        # This feature is required for VPP to process DHCP packets and assign addresses.
-        if 'dhcp' in ethernet.get('address', []):
-            vpp_api.enable_dhcp_client(ifname)
-        else:
-            vpp_api.disable_dhcp_client(ifname)
-
-        # Enable ip6-icmp-ra-punt feature for DHCPv6-configured interfaces.
-        if 'dhcpv6' in ethernet.get('address', []) or (
-            'autoconf' in ethernet.get('ipv6', {}).get('address', {})
-        ):
-            vpp_api.enable_icmpv6_ra_punt(ifname)
-        else:
-            vpp_api.disable_icmpv6_ra_punt(ifname)
+        # Enable ip4-dhcp-client-detect/ip6-icmp-ra-punt features for
+        # DHCP/DHCPv6/autoconf-configured interfaces. These features are
+        # required for VPP to process DHCP(v6) packets and assign addresses.
+        # Applies to the interface itself and its VLAN sub-interfaces
+        # (vif, vif_s).vif-c (Q-in-Q) is intentionally excluded, as it is
+        # not currently functional under VPP.
+        dhcp_targets = [(ifname, ethernet)]
+        dhcp_targets += [
+            (vif['ifname'], vif) for vif in ethernet.get('vif', {}).values()
+        ]
+        dhcp_targets += [
+            (vif_s['ifname'], vif_s) for vif_s in ethernet.get('vif_s', {}).values()
+        ]
+
+        for dhcp_ifname, dhcp_config in dhcp_targets:
+            if 'dhcp' in dhcp_config.get('address', []):
+                vpp_api.enable_dhcp_client(dhcp_ifname)
+            else:
+                vpp_api.disable_dhcp_client(dhcp_ifname)
+
+            if 'dhcpv6' in dhcp_config.get('address', []) or (
+                'autoconf' in dhcp_config.get('ipv6', {}).get('address', {})
+            ):
+                vpp_api.enable_icmpv6_ra_punt(dhcp_ifname)
+            else:
+                vpp_api.disable_icmpv6_ra_punt(dhcp_ifname)
 
         # If the interface is managed by the VPP DPDK driver, synchronize runtime
         # parameters between Linux and the corresponding VPP LCP interface