Ignore case in DNS forwards lookup results

python/nav/asyncdns.py

@@ -71,7 +71,7 @@ class Resolver(object):
 
     def __init__(self):
         self._resolvers = cycle(
-            [client.Resolver('/etc/resolv.conf') for _i in range(3)]
+            [client.Resolver("/etc/resolv.conf") for _i in range(3)]
         )
         self.results = defaultdict(list)
         self._finished = False
@@ -136,7 +136,7 @@ def lookup(self, name):
         """Returns a deferred object with all records related to hostname"""
 
         if isinstance(name, str):
-            name = name.encode('idna')
+            name = name.encode("idna")
 
         resolver = next(self._resolvers)
         return [resolver.lookupAddress(name), resolver.lookupIPV6Address(name)]
@@ -148,7 +148,7 @@ def _extract_records(result, name):
 
         for record_list in result:
             for record in record_list:
-                if str(record.name) == name:
+                if str(record.name).lower() == name.lower():
                     if record.type == dns.A:
                         address_list.append(
                             socket.inet_ntop(socket.AF_INET, record.payload.address)

tests/unittests/asyncdns_test.py

@@ -0,0 +1,42 @@
+from mock import Mock
+from twisted.names import dns
+
+from nav.asyncdns import ForwardResolver
+
+BUICK_NAME = "buick.lab.uninett.no"
+
+
+def test_forward_lookup_should_work_with_ipv4_results():
+    record = Mock()
+    record.name = BUICK_NAME
+    record.type = dns.A
+    record.payload.address = b"\xac\x00\x00\x01"
+    result = [[record]]
+    result_name, address_list = ForwardResolver._extract_records(result, BUICK_NAME)
+
+    assert result_name == BUICK_NAME
+    assert address_list == ["172.0.0.1"]
+
+
+def test_forward_lookup_should_work_with_ipv6_results():
+    record = Mock()
+    record.name = BUICK_NAME
+    record.type = dns.AAAA
+    record.payload.address = b" \x01\r\xb833DDUUffww\x88\x88"
+    result = [[record]]
+    result_name, address_list = ForwardResolver._extract_records(result, BUICK_NAME)
+
+    assert result_name == BUICK_NAME
+    assert address_list == ["2001:db8:3333:4444:5555:6666:7777:8888"]
+
+
+def test_forward_lookup_should_work_with_different_case_name_results():
+    record = Mock()
+    record.name = "bUiCk.LaB.uNiNeTt.No"
+    record.type = dns.A
+    record.payload.address = b"\x9e&\x98\xa2"
+    result = [[record]]
+    result_name, address_list = ForwardResolver._extract_records(result, BUICK_NAME)
+
+    assert result_name == BUICK_NAME
+    assert address_list == ["158.38.152.162"]