improve default route service to detect connected routers and use the addresses of the first one found

daemon/core/services/utility.py

@@ -1,13 +1,13 @@
 """
 utility.py: defines miscellaneous utility services.
 """
-
 import os
 
 import netaddr
 
 from core import constants, utils
 from core.errors import CoreCommandError
+from core.nodes.base import CoreNode
 from core.services.coreservices import CoreService, ServiceMode
 
 
@@ -77,27 +77,26 @@ class DefaultRouteService(UtilService):
 
     @classmethod
     def generate_config(cls, node, filename):
+        # only add default routes for linked routing nodes
+        routes = []
+        for other_node in node.session.nodes.values():
+            if not isinstance(other_node, CoreNode):
+                continue
+            if other_node.type not in ["router", "mdr"]:
+                continue
+            commonnets = node.commonnets(other_node)
+            if commonnets:
+                _, _, router_eth = commonnets[0]
+                for x in router_eth.addrlist:
+                    addr, prefix = x.split("/")
+                    routes.append(addr)
+                break
         cfg = "#!/bin/sh\n"
         cfg += "# auto-generated by DefaultRoute service (utility.py)\n"
-        for ifc in node.netifs():
-            if hasattr(ifc, "control") and ifc.control is True:
-                continue
-            cfg += "\n".join(map(cls.addrstr, ifc.addrlist))
-            cfg += "\n"
+        for route in routes:
+            cfg += f"ip route add default via {route}\n"
         return cfg
 
-    @staticmethod
-    def addrstr(x):
-        net = netaddr.IPNetwork(x)
-        if net[1] == net[-2]:
-            return ""
-        else:
-            if os.uname()[0] == "Linux":
-                rtcmd = "ip route add default via"
-            else:
-                raise Exception("unknown platform")
-            return "%s %s" % (rtcmd, net[1])
-
 
 class DefaultMulticastRouteService(UtilService):
     name = "DefaultMulticastRoute"