Include aliases in the fqdns grains

Add UT for "is_fqdn"

Add "is_fqdn" check to the network utils

Bugfix: include FQDNs aliases

Deprecate UnitTest assertion in favour of built-in assert keyword

Add UT for fqdns aliases

Leverage cached interfaces, if any.

salt/grains/core.py

@@ -2191,14 +2191,13 @@ def fqdns():
     grains = {}
     fqdns = set()
 
-    addresses = salt.utils.network.ip_addrs(include_loopback=False,
-                                            interface_data=_INTERFACES)
-    addresses.extend(salt.utils.network.ip_addrs6(include_loopback=False,
-                                                  interface_data=_INTERFACES))
+    addresses = salt.utils.network.ip_addrs(include_loopback=False, interface_data=_get_interfaces())
+    addresses.extend(salt.utils.network.ip_addrs6(include_loopback=False, interface_data=_get_interfaces()))
     err_message = 'Exception during resolving address: %s'
     for ip in addresses:
         try:
-            fqdns.add(socket.getfqdn(socket.gethostbyaddr(ip)[0]))
+            name, aliaslist, addresslist = socket.gethostbyaddr(ip)
+            fqdns.update([socket.getfqdn(name)] + [als for als in aliaslist if salt.utils.network.is_fqdn(als)])
         except socket.herror as err:
             if err.errno == 0:
                 # No FQDN for this IP address, so we don't need to know this all the time.
@@ -2208,8 +2207,7 @@ def fqdns():
         except (socket.error, socket.gaierror, socket.timeout) as err:
             log.error(err_message, err)
 
-    grains['fqdns'] = sorted(list(fqdns))
-    return grains
+    return {"fqdns": sorted(list(fqdns))}
 
 
 def ip_fqdn():

salt/utils/network.py

@@ -1904,3 +1904,15 @@ def dns_check(addr, port, safe=False, ipv6=None):
             raise SaltClientError()
         raise SaltSystemExit(code=42, msg=err)
     return resolved
+
+
+def is_fqdn(hostname):
+    """
+    Verify if hostname conforms to be a FQDN.
+
+    :param hostname: text string with the name of the host
+    :return: bool, True if hostname is correct FQDN, False otherwise
+    """
+
+    compliant = re.compile(r"(?!-)[A-Z\d\-\_]{1,63}(?<!-)$", re.IGNORECASE)
+    return "." in hostname and len(hostname) < 0xff and all(compliant.match(x) for x in hostname.rstrip(".").split("."))

tests/unit/grains/test_core.py

@@ -863,10 +863,32 @@ def test_fqdns_return(self):
         ret = {'fqdns': ['bluesniff.foo.bar', 'foo.bar.baz', 'rinzler.evil-corp.com']}
         with patch.object(socket, 'gethostbyaddr', side_effect=reverse_resolv_mock):
             fqdns = core.fqdns()
-            self.assertIn('fqdns', fqdns)
-            self.assertEqual(len(fqdns['fqdns']), len(ret['fqdns']))
-            self.assertEqual(set(fqdns['fqdns']), set(ret['fqdns']))
+            assert "fqdns" in fqdns
+            assert len(fqdns['fqdns']) == len(ret['fqdns'])
+            assert set(fqdns['fqdns']) == set(ret['fqdns'])
 
+    @skipIf(not salt.utils.platform.is_linux(), 'System is not Linux')
+    @patch.object(salt.utils.platform, 'is_windows', MagicMock(return_value=False))
+    @patch('salt.utils.network.ip_addrs', MagicMock(return_value=['1.2.3.4', '5.6.7.8']))
+    @patch('salt.utils.network.ip_addrs6',
+           MagicMock(return_value=['fe80::a8b2:93ff:fe00:0', 'fe80::a8b2:93ff:dead:beef']))
+    @patch('salt.utils.network.socket.getfqdn', MagicMock(side_effect=lambda v: v))  # Just pass-through
+    def test_fqdns_aliases(self):
+        '''
+        FQDNs aliases
+        '''
+        reverse_resolv_mock = [('foo.bar.baz', ["throwmeaway", "this.is.valid.alias"], ['1.2.3.4']),
+                               ('rinzler.evil-corp.com', ["false-hostname", "badaliass"], ['5.6.7.8']),
+                               ('foo.bar.baz', [], ['fe80::a8b2:93ff:fe00:0']),
+                               ('bluesniff.foo.bar', ["alias.bluesniff.foo.bar"], ['fe80::a8b2:93ff:dead:beef'])]
+        with patch.object(socket, 'gethostbyaddr', side_effect=reverse_resolv_mock):
+            fqdns = core.fqdns()
+            assert "fqdns" in fqdns
+            for alias in ["this.is.valid.alias", "alias.bluesniff.foo.bar"]:
+                assert alias in fqdns["fqdns"]
+
+            for alias in ["throwmeaway", "false-hostname", "badaliass"]:
+                assert alias not in fqdns["fqdns"]
     def test_core_virtual(self):
         '''
         test virtual grain with cmd virt-what

tests/unit/utils/test_network.py

@@ -547,3 +547,22 @@ def test_mac_str_to_bytes(self):
         self.assertRaises(ValueError, network.mac_str_to_bytes, 'a0:b0:c0:d0:e0:fg')
         self.assertEqual(b'\x10\x08\x06\x04\x02\x00', network.mac_str_to_bytes('100806040200'))
         self.assertEqual(b'\xf8\xe7\xd6\xc5\xb4\xa3', network.mac_str_to_bytes('f8e7d6c5b4a3'))
+
+    def test_is_fqdn(self):
+        """
+        Test is_fqdn function passes possible FQDN names.
+
+        :return: None
+        """
+        for fqdn in ["host.domain.com", "something.with.the.dots.still.ok", "UPPERCASE.ALSO.SHOULD.WORK",
+                     "MiXeD.CaSe.AcCePtAbLe", "123.host.com", "host123.com", "some_underscore.com", "host-here.com"]:
+            assert network.is_fqdn(fqdn)
+
+    def test_is_not_fqdn(self):
+        """
+        Test is_fqdn function rejects FQDN names.
+
+        :return: None
+        """
+        for fqdn in ["hostname", "/some/path", "$variable.here", "verylonghostname.{}".format("domain" * 45)]:
+            assert not network.is_fqdn(fqdn)