libvirt: Always escape IPv6 addresses when used in migration URI

If IPv6 is passed to URI it should be wrapped within square brackets.
This patch detects IPv6 to form migration URI properly. Domain name, IPv4 or
already bracketed IPv6 address will pass as is

Extend tests to include collapsed IPv6 addresses and IPv6 addresses with
port

Change-Id: I1201db996ea6ceaebd49479b298d74585a78b006
Closes-Bug: #1786058

nova/tests/unit/virt/libvirt/test_driver.py

@@ -9910,6 +9910,10 @@ class LibvirtConnTestCase(test.NoDBTestCase,
                              etree.tostring(config, encoding='unicode'))
 
     def test_live_migration_uri(self):
+        addresses = ('127.0.0.1', '127.0.0.1:4444', '[::1]:4444',
+                    '[0:0:0:0:0:0:0:1]:4444', u'127.0.0.1', u'destination',
+        )
+
         hypervisor_uri_map = (
             ('xen', 'xenmigr://%s/system'),
             ('kvm', 'qemu+tcp://%s/system'),
@@ -9918,17 +9922,42 @@ class LibvirtConnTestCase(test.NoDBTestCase,
             # anything else will return None
             ('lxc', None),
         )
-        dest = 'destination'
-        for hyperv, uri in hypervisor_uri_map:
-            self.flags(virt_type=hyperv, group='libvirt')
-            drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), False)
-            if uri is not None:
-                uri = uri % dest
-                self.assertEqual(uri, drvr._live_migration_uri(dest))
-            else:
-                self.assertRaises(exception.LiveMigrationURINotAvailable,
-                                  drvr._live_migration_uri,
-                                  dest)
+
+        drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), False)
+        for dest in addresses:
+            for hyperv, uri in hypervisor_uri_map:
+                self.flags(virt_type=hyperv, group='libvirt')
+                if uri is not None:
+                    uri = uri % dest
+                    self.assertEqual(uri, drvr._live_migration_uri(dest))
+                else:
+                    self.assertRaises(exception.LiveMigrationURINotAvailable,
+                                      drvr._live_migration_uri,
+                                      dest)
+
+    def test_live_migration_uri_ipv6(self):
+        addresses = ('::1', '0:0:0:0:0:0:0:1', u'::1')
+
+        hypervisor_uri_map = (
+            ('xen', 'xenmigr://[%s]/system'),
+            ('kvm', 'qemu+tcp://[%s]/system'),
+            ('qemu', 'qemu+tcp://[%s]/system'),
+            ('parallels', 'parallels+tcp://[%s]/system'),
+            # anything else will return None
+            ('lxc', None),
+        )
+
+        for dest in addresses:
+            for hyperv, uri in hypervisor_uri_map:
+                self.flags(virt_type=hyperv, group='libvirt')
+                drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), False)
+                if uri is not None:
+                    uri = uri % dest
+                    self.assertEqual(uri, drvr._live_migration_uri(dest))
+                else:
+                    self.assertRaises(exception.LiveMigrationURINotAvailable,
+                                      drvr._live_migration_uri,
+                                      dest)
 
     def test_live_migration_uri_forced(self):
         dest = 'destination'
@@ -9984,12 +10013,26 @@ class LibvirtConnTestCase(test.NoDBTestCase,
         self.flags(virt_type='kvm', group='libvirt')
 
         drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), False)
-        addresses = ('127.0.0.1', '127.0.0.1:4444',
-                     '0:0:0:0:0:0:0:1', '[0:0:0:0:0:0:0:1]:4444',
-                     u'127.0.0.1', u'destination')
+        addresses = ('127.0.0.1', '127.0.0.1:4444', '[::1]:4444',
+                    '[0:0:0:0:0:0:0:1]:4444', u'127.0.0.1', u'destination',
+        )
+
         for dest in addresses:
+            uri = 'tcp://%s'
             result = drvr._migrate_uri(dest)
-            self.assertEqual('tcp://%s' % dest, result)
+            self.assertEqual(uri % dest, result)
+            self.assertIsInstance(result, str)
+
+    def test_migrate_uri_forced_live_migration_inboud_addr_ipv6(self):
+        self.flags(virt_type='kvm', group='libvirt')
+
+        drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), False)
+        addresses = ('::1', '0:0:0:0:0:0:0:1', u'::1')
+
+        for dest in addresses:
+            uri = 'tcp://[%s]'
+            result = drvr._migrate_uri(dest)
+            self.assertEqual(uri % dest, result)
             self.assertIsInstance(result, str)
 
     def test_update_volume_xml_no_serial(self):

nova/virt/libvirt/driver.py

@@ -61,6 +61,7 @@ from oslo_utils import encodeutils
 from oslo_utils import excutils
 from oslo_utils import fileutils
 from oslo_utils import importutils
+from oslo_utils import netutils as oslo_netutils
 from oslo_utils import strutils
 from oslo_utils import timeutils
 from oslo_utils import units
@@ -734,6 +735,8 @@ class LibvirtDriver(driver.ComputeDriver):
             'xen': 'xenmigr://%s/system',
             'parallels': 'parallels+tcp://%s/system',
         }
+        dest = oslo_netutils.escape_ipv6(dest)
+
         virt_type = CONF.libvirt.virt_type
         # TODO(pkoniszewski): Remove fetching live_migration_uri in Pike
         uri = CONF.libvirt.live_migration_uri
@@ -753,6 +756,8 @@ class LibvirtDriver(driver.ComputeDriver):
     @staticmethod
     def _migrate_uri(dest):
         uri = None
+        dest = oslo_netutils.escape_ipv6(dest)
+
         # Only QEMU live migrations supports migrate-uri parameter
         virt_type = CONF.libvirt.virt_type
         if virt_type in ('qemu', 'kvm'):

releasenotes/notes/libvirt_fix_ipv6_live_migration-bbcde8f3b7d17921.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - A change has been introduced in the libvirt driver to correctly handle
+    IPv6 addresses for live migration.