Merge lp:~lamont/maas/bug-1603590-1.9 into lp:maas/1.9

[LaMont Jones]

Allow link-local addresses (fe80::/64) for the default gateway for a subnet.

Allow link-local addresses (fe80::/64) for the default gateway for a subnet.

[Mike Pontillo (mpontillo)]

LGTM.

review: Approve

=== modified file 'docs/changelog.rst'
--- docs/changelog.rst	2016-07-13 01:23:13 +0000
+++ docs/changelog.rst	2016-07-18 17:26:29 +0000
@@ -2,6 +2,11 @@
 Changelog
 =========
 
+1.9.5
+=====
+
+LP: #1603590    [1.9] MAAS does not allow link-local address for default gateway on ipv6 subnet.
+
 1.9.4
 =====
 
 
=== modified file 'src/maasserver/models/subnet.py'
--- src/maasserver/models/subnet.py	2015-12-03 10:41:08 +0000
+++ src/maasserver/models/subnet.py	2016-07-18 17:26:29 +0000
@@ -383,7 +383,17 @@
         if self.gateway_ip is None or self.gateway_ip == '':
             return
         gateway_addr = IPAddress(self.gateway_ip)
-        if gateway_addr not in self.get_ipnetwork():
+        network = self.get_ipnetwork()
+        if gateway_addr in network:
+            # If the gateway is in the network, it is fine.
+            return
+        elif network.version == 6 and gateway_addr.is_link_local():
+            # If this is an IPv6 network and the gateway is in the link-local
+            # network (fe80::/64 -- required to be configured by the spec),
+            # then it is also valid.
+            return
+        else:
+            # The gateway is not valid for the network.
             message = "Gateway IP must be within CIDR range."
             raise ValidationError({'gateway_ip': [message]})
 
 
=== modified file 'src/maasserver/models/tests/test_subnet.py'
--- src/maasserver/models/tests/test_subnet.py	2015-11-06 01:55:30 +0000
+++ src/maasserver/models/tests/test_subnet.py	2016-07-18 17:26:29 +0000
@@ -445,6 +445,23 @@
             {'gateway_ip': ["Gateway IP must be within CIDR range."]},
             error.message_dict)
 
+    def test_allows_fe80_gateway(self):
+        network = factory.make_ipv6_network(slash=64)
+        gateway_ip = factory.pick_ip_in_network(IPNetwork('fe80::/64'))
+        subnet = factory.make_Subnet(
+            cidr=unicode(network), gateway_ip=gateway_ip)
+        self.assertEqual(subnet.gateway_ip, gateway_ip)
+
+    def test_denies_fe80_gateway_for_ipv4(self):
+        network = factory.make_ipv4_network(slash=22)
+        gateway_ip = factory.pick_ip_in_network(IPNetwork('fe80::/64'))
+        error = self.assertRaises(
+            ValidationError, factory.make_Subnet,
+            cidr=unicode(network), gateway_ip=gateway_ip)
+        self.assertEqual(
+            {'gateway_ip': ["Gateway IP must be within CIDR range."]},
+            error.message_dict)
+
     def test_create_from_cidr_creates_subnet(self):
         vlan = factory.make_VLAN()
         cidr = unicode(factory.make_ip4_or_6_network().cidr)