Merge lp:~niedbalski/charm-helpers/lp1671861 into lp:charm-helpers

[Jorge Niedbalski]

Fix required for solving LP: #1671861.

- Extends the get_address_in_network function
to use a prefix when the netmask comes in the 'ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff::/128' format.

- Link-local and loopback addresses are skipped
- Added tests to validate the change.

[lp:~niedbalski/charm-helpers/lp1671861]

714. By Jorge Niedbalski on 2017-03-10

Additional fix

715. By Jorge Niedbalski on 2017-03-10

Additional fixes to the _get_address_from_network function

[Felipe Reyes (freyes)]

the tests are OK, and the code looks code to me.

I tested the code against my local ipv6 address and does the right thing detecting them.

[Felipe Reyes (freyes)]

review: Approve

=== modified file 'charmhelpers/contrib/network/ip.py'
--- charmhelpers/contrib/network/ip.py	2017-03-06 23:51:06 +0000
+++ charmhelpers/contrib/network/ip.py	2017-03-10 18:27:45 +0000
@@ -67,6 +67,24 @@
     raise ValueError(errmsg)
 
 
+def _get_ipv6_network_from_address(address):
+    """Get an netaddr.IPNetwork for the given IPv6 address
+    :param address: a dict as returned by netifaces.ifaddresses
+    :returns netaddr.IPNetwork: None if the address is a link local or loopback
+    address
+    """
+    if address['addr'].startswith('fe80') or address['addr'] == "::1":
+        return None
+
+    prefix = address['netmask'].split("/")
+    if len(prefix) > 1:
+        netmask = prefix[1]
+    else:
+        netmask = address['netmask']
+    return netaddr.IPNetwork("%s/%s" % (address['addr'],
+                                        netmask))
+
+
 def get_address_in_network(network, fallback=None, fatal=False):
     """Get an IPv4 or IPv6 address within the network from the host.
 
@@ -100,11 +118,9 @@
 
             if network.version == 6 and netifaces.AF_INET6 in addresses:
                 for addr in addresses[netifaces.AF_INET6]:
-                    if not addr['addr'].startswith('fe80'):
-                        cidr = netaddr.IPNetwork("%s/%s" % (addr['addr'],
-                                                            addr['netmask']))
-                        if cidr in network:
-                            return str(cidr.ip)
+                    cidr = _get_ipv6_network_from_address(addr)
+                    if cidr and cidr in network:
+                        return str(cidr.ip)
 
     if fallback is not None:
         return fallback
@@ -180,18 +196,18 @@
 
         if address.version == 6 and netifaces.AF_INET6 in addresses:
             for addr in addresses[netifaces.AF_INET6]:
-                if not addr['addr'].startswith('fe80'):
-                    network = netaddr.IPNetwork("%s/%s" % (addr['addr'],
-                                                           addr['netmask']))
-                    cidr = network.cidr
-                    if address in cidr:
-                        if key == 'iface':
-                            return iface
-                        elif key == 'netmask' and cidr:
-                            return str(cidr).split('/')[1]
-                        else:
-                            return addr[key]
+                network = _get_ipv6_network_from_address(addr)
+                if not network:
+                    continue
 
+                cidr = network.cidr
+                if address in cidr:
+                    if key == 'iface':
+                        return iface
+                    elif key == 'netmask' and cidr:
+                        return str(cidr).split('/')[1]
+                    else:
+                        return addr[key]
     return None
 
 

=== modified file 'tests/contrib/network/test_ip.py'
--- tests/contrib/network/test_ip.py	2017-03-06 23:51:06 +0000
+++ tests/contrib/network/test_ip.py	2017-03-10 18:27:45 +0000
@@ -34,6 +34,8 @@
               'netmask': 'ffff:ffff:ffff:ffff::'},
              {'addr': 'fe80::3e97:eff:fe8b:1cf7%eth0',
               'netmask': 'ffff:ffff:ffff:ffff::'},
+             {'netmask': 'ffff:ffff:ffff:ffff::/64',
+              'addr': 'fd2d:dec4:cf59:3c16::1'},
              {'addr': '2001:db8:1::',
               'netmask': 'ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff'}],
         17: [{'addr': '3c:97:0e:8b:1c:f7',
@@ -214,6 +216,19 @@
     def test_get_address_in_network_not_found_not_fatal(self):
         self._test_get_address_in_network(None, '172.16.0.0/16', fatal=False)
 
+    @patch.object(netifaces, 'ifaddresses')
+    @patch.object(netifaces, 'interfaces')
+    def test_get_address_in_network_netmask(self, _interfaces, _ifaddresses):
+        """
+        Validates that get_address_in_network works with a netmask
+        that uses the format 'ffff:ffff:ffff::/prefixlen'
+        """
+        _interfaces.return_value = DUMMY_ADDRESSES.keys()
+        _ifaddresses.side_effect = DUMMY_ADDRESSES.__getitem__
+        self._test_get_address_in_network('fd2d:dec4:cf59:3c16::1',
+                                          'fd2d:dec4:cf59:3c16::/64',
+                                          fatal=False)
+
     def test_is_address_in_network(self):
         self.assertTrue(
             net_ip.is_address_in_network(