Abstract procedures for IP address warnings

Originaly there should be only two occurencees of this warning, one for
server, one for client. But obviously is not possible with current
installers to achive this goal, so I have to extract code to not mess
with 5 times copy and paste.

https://fedorahosted.org/freeipa/ticket/5814

Reviewed-By: David Kupka <dkupka@redhat.com>

ipalib/util.py

@@ -21,7 +21,10 @@
 Various utility functions.
 """
 
-from __future__ import absolute_import
+from __future__ import (
+    absolute_import,
+    print_function,
+)
 
 import os
 import socket
@@ -29,6 +32,7 @@ import re
 import decimal
 import dns
 import encodings
+import sys
 from weakref import WeakKeyDictionary
 
 import netaddr
@@ -45,6 +49,7 @@ from ipapython.ssh import SSHPublicKey
 from ipapython.dn import DN, RDN
 from ipapython.dnsutil import DNSName
 from ipapython.dnsutil import resolve_ip_addresses
+from ipapython.ipa_log_manager import root_logger
 
 if six.PY3:
     unicode = str
@@ -994,3 +999,23 @@ def check_principal_realm_in_trust_namespace(api_instance, *keys):
                 name='krbprincipalname',
                 error=_('realm or UPN suffix overlaps with trusted domain '
                         'namespace'))
+
+
+def network_ip_address_warning(addr_list):
+    for ip in addr_list:
+        if ip.is_network_addr():
+            root_logger.warning("IP address %s might be network address", ip)
+            # fixme: once when loggers will be fixed, we can remove this
+            # print
+            print("WARNING: IP address {} might be network address".format(ip),
+                  file=sys.stderr)
+
+
+def broadcast_ip_address_warning(addr_list):
+    for ip in addr_list:
+        if ip.is_broadcast_addr():
+            root_logger.warning("IP address %s might be broadcast address", ip)
+            # fixme: once when loggers will be fixed, we can remove this
+            # print
+            print("WARNING: IP address {} might be broadcast address".format(
+                ip), file=sys.stderr)