From a298fd775b537839214802f161634215d2f827a8 Mon Sep 17 00:00:00 2001

From: Chad Smith <chad.smith@canonical.com>

Date: Tue, 9 May 2017 20:23:05 -0600

Subject: [PATCH] sysconfig: Raise ValueError when multiple default gateways

 are present.

Fixed setting Route.has_set_default_ipv6 or *_ipv4 to track whether a

route already has a default gateway defined. The code was setting

Route.has_set_default which wasn't checked when raising "duplicate

gateway" ValueErrors. Added unit tests to exercise this expected raised

ValueError. Also moved is_ipv6 = subnet.get('ipv6') logic out of a for

loop because we don't need to recalculate the same value every route

iteration.

LP: #1687485

(cherry picked from commit dd03bb411c9a6f10854a3bbc3223b204c3d4d174)

Resolves: rhbz#1438082

---

 cloudinit/net/sysconfig.py  | 14 ++++-----

 tests/unittests/test_net.py | 76 +++++++++++++++++++++++++++++++++++++++++++++

 2 files changed, 83 insertions(+), 7 deletions(-)

diff --git a/cloudinit/net/sysconfig.py b/cloudinit/net/sysconfig.py

index 29c906f..d521d5c 100644

--- a/cloudinit/net/sysconfig.py

+++ b/cloudinit/net/sysconfig.py

@@ -230,12 +230,8 @@ class Renderer(renderer.Renderer):

                                                       iface_cfg.name))

         if 'netmask' in subnet:

             iface_cfg['NETMASK'] = subnet['netmask']

+        is_ipv6 = subnet.get('ipv6')

         for route in subnet.get('routes', []):

-            if subnet.get('ipv6'):

-                gw_cfg = 'IPV6_DEFAULTGW'

-            else:

-                gw_cfg = 'GATEWAY'

-

             if _is_default_route(route):

                 if (

                         (subnet.get('ipv4') and

@@ -256,8 +252,12 @@ class Renderer(renderer.Renderer):

                 # also provided the default route?

                 iface_cfg['DEFROUTE'] = True

                 if 'gateway' in route:

-                    iface_cfg[gw_cfg] = route['gateway']

-                route_cfg.has_set_default = True

+                    if is_ipv6:

+                        iface_cfg['IPV6_DEFAULTGW'] = route['gateway']

+                        route_cfg.has_set_default_ipv6 = True

+                    else:

+                        iface_cfg['GATEWAY'] = route['gateway']

+                        route_cfg.has_set_default_ipv4 = True

             else:

                 gw_key = 'GATEWAY%s' % route_cfg.last_idx

                 nm_key = 'NETMASK%s' % route_cfg.last_idx

diff --git a/tests/unittests/test_net.py b/tests/unittests/test_net.py

index ce13664..262c6d5 100755

--- a/tests/unittests/test_net.py

+++ b/tests/unittests/test_net.py

@@ -515,6 +515,82 @@ USERCTL=no

 """.lstrip()

             self.assertEqual(expected_content, content)

+    def test_multiple_ipv4_default_gateways(self):

+        """ValueError is raised when duplicate ipv4 gateways exist."""

+        net_json = {

+            "services": [{"type": "dns", "address": "172.19.0.12"}],

+            "networks": [{

+                "network_id": "dacd568d-5be6-4786-91fe-750c374b78b4",

+                "type": "ipv4", "netmask": "255.255.252.0",

+                "link": "tap1a81968a-79",

+                "routes": [{

+                    "netmask": "0.0.0.0",

+                    "network": "0.0.0.0",

+                    "gateway": "172.19.3.254",

+                }, {

+                    "netmask": "0.0.0.0",  # A second default gateway

+                    "network": "0.0.0.0",

+                    "gateway": "172.20.3.254",

+                }],

+                "ip_address": "172.19.1.34", "id": "network0"

+            }],

+            "links": [

+                {

+                    "ethernet_mac_address": "fa:16:3e:ed:9a:59",

+                    "mtu": None, "type": "bridge", "id":

+                    "tap1a81968a-79",

+                    "vif_id": "1a81968a-797a-400f-8a80-567f997eb93f"

+                },

+            ],

+        }

+        macs = {'fa:16:3e:ed:9a:59': 'eth0'}

+        render_dir = self.tmp_dir()

+        network_cfg = openstack.convert_net_json(net_json, known_macs=macs)

+        ns = network_state.parse_net_config_data(network_cfg,

+                                                 skip_broken=False)

+        renderer = sysconfig.Renderer()

+        with self.assertRaises(ValueError):

+            renderer.render_network_state(ns, render_dir)

+        self.assertEqual([], os.listdir(render_dir))

+

+    def test_multiple_ipv6_default_gateways(self):

+        """ValueError is raised when duplicate ipv6 gateways exist."""

+        net_json = {

+            "services": [{"type": "dns", "address": "172.19.0.12"}],

+            "networks": [{

+                "network_id": "public-ipv6",

+                "type": "ipv6", "netmask": "",

+                "link": "tap1a81968a-79",

+                "routes": [{

+                    "gateway": "2001:DB8::1",

+                    "netmask": "::",

+                    "network": "::"

+                }, {

+                    "gateway": "2001:DB9::1",

+                    "netmask": "::",

+                    "network": "::"

+                }],

+                "ip_address": "2001:DB8::10", "id": "network1"

+            }],

+            "links": [

+                {

+                    "ethernet_mac_address": "fa:16:3e:ed:9a:59",

+                    "mtu": None, "type": "bridge", "id":

+                    "tap1a81968a-79",

+                    "vif_id": "1a81968a-797a-400f-8a80-567f997eb93f"

+                },

+            ],

+        }

+        macs = {'fa:16:3e:ed:9a:59': 'eth0'}

+        render_dir = self.tmp_dir()

+        network_cfg = openstack.convert_net_json(net_json, known_macs=macs)

+        ns = network_state.parse_net_config_data(network_cfg,

+                                                 skip_broken=False)

+        renderer = sysconfig.Renderer()

+        with self.assertRaises(ValueError):

+            renderer.render_network_state(ns, render_dir)

+        self.assertEqual([], os.listdir(render_dir))

+

     def test_openstack_rendering_samples(self):

         tmp_dir = tempfile.mkdtemp()

         self.addCleanup(shutil.rmtree, tmp_dir)