Allow Ipv6 addresses for nova_metadata_host

Current logic didn't check if the nova_metadata_host is an IPv6 address
causing the proxy request to fail with an exception because the url is
not valid.

This patchs check if the nova_metadata_host is an IPv6 address and
create a valid url enclosing the IPv6 address with brackets

Closes-Bug: #1796593

Change-Id: Ibfebffcec2c8860237a1f151084de978a7863bd8
Signed-off-by: aojeagarcia <aojeagarcia@suse.com>
(cherry picked from commit 85588ad38e)

neutron/agent/metadata/agent.py

@@ -32,6 +32,7 @@ from neutron.agent.linux import utils as agent_utils
 from neutron.agent import rpc as agent_rpc
 from neutron.common import cache_utils as cache
 from neutron.common import constants as n_const
+from neutron.common import ipv6_utils
 from neutron.common import rpc as n_rpc
 from neutron.common import topics
 from neutron.conf.agent.metadata import config
@@ -172,8 +173,10 @@ class MetadataProxyHandler(object):
             'X-Instance-ID-Signature': self._sign_instance_id(instance_id)
         }
 
-        nova_host_port = '%s:%s' % (self.conf.nova_metadata_host,
-                                    self.conf.nova_metadata_port)
+        nova_host_port = ipv6_utils.valid_ipv6_url(
+            self.conf.nova_metadata_host,
+            self.conf.nova_metadata_port)
+
         url = urlparse.urlunsplit((
             self.conf.nova_metadata_protocol,
             nova_host_port,

neutron/common/ipv6_utils.py

@@ -75,3 +75,15 @@ def is_ipv6_pd_enabled(subnet):
        constants.IPV6_PD_POOL_ID
     """
     return subnet.get('subnetpool_id') == const.IPV6_PD_POOL_ID
+
+
+def valid_ipv6_url(host, port):
+    """Given a host and a port returns a valid URL
+       RFC2732 https://tools.ietf.org/html/rfc2732
+       square brackets always required in ipv6 URI.
+    """
+    if netaddr.valid_ipv6(host):
+        uri = '[%s]:%s' % (host, port)
+    else:
+        uri = '%s:%s' % (host, port)
+    return uri

neutron/tests/unit/common/test_ipv6_utils.py

@@ -113,3 +113,28 @@ class TestIsEui64Address(base.BaseTestCase):
                'fffe::0cad:12fe:fe44:5566',
                'ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff')
         self._test_eui_64(ips, False)
+
+
+class TestValidIpv6URL(base.BaseTestCase):
+
+    def test_valid_ipv6_url(self):
+        host = "::1"
+        port = 443
+        self.assertEqual("[::1]:443", ipv6_utils.valid_ipv6_url(host, port))
+
+    def test_invalid_ipv6_url(self):
+        host = "::1"
+        port = 443
+        self.assertNotEqual("::1:443", ipv6_utils.valid_ipv6_url(host, port))
+
+    def test_valid_ipv4_url(self):
+        host = "192.168.1.2"
+        port = 443
+        self.assertEqual("192.168.1.2:443",
+                         ipv6_utils.valid_ipv6_url(host, port))
+
+    def test_valid_hostname_url(self):
+        host = "controller"
+        port = 443
+        self.assertEqual("controller:443",
+                         ipv6_utils.valid_ipv6_url(host, port))