[fix] WireGuard auto tunnel provisioning broken with IPv6 #721

openwisp_controller/config/base/vpn.py

@@ -629,6 +629,12 @@ def auto_client(self, auto_cert=True, template_backend_class=None):
                     vxlan=self.config.get("vxlan", [{}])[0],
                     **context_keys,
                 )
+                if self.subnet and self.subnet.subnet.version == 6:
+                    for interface in auto.get("interfaces", []):
+                        if interface.get("type") == "wireguard":
+                            for addr in interface.get("addresses", []):
+                                addr["family"] = "ipv6"
+                                addr["mask"] = 128
             # If the backend is 'zerotier' then
             # call auto_client and update the config
             elif self._is_backend_type("zerotier") and template_backend_class:

openwisp_controller/config/tests/test_vpn.py

@@ -640,6 +640,20 @@ def test_auto_client(self):
         )
         self.assertEqual(auto, expected)
 
+    def test_auto_client_ipv6(self):
+        device, vpn, template = self._create_wireguard_vpn_template(
+            vpn_options={
+                "subnet": self._create_subnet(
+                    name="wireguard ipv6", subnet="fdca:1234::/64"
+                )
+            }
+        )
+        auto = vpn.auto_client(template_backend_class=template.backend_class)
+        addresses = auto["interfaces"][0]["addresses"]
+        self.assertEqual(len(addresses), 1)
+        self.assertEqual(addresses[0]["family"], "ipv6")
+        self.assertEqual(addresses[0]["mask"], 128)
+
     def test_change_vpn_backend(self):
         vpn = self._create_vpn(name="new", backend=self._BACKENDS["openvpn"])
         subnet = self._create_subnet(