Merge pull request #2930 from Netflix/powerdnsplugin_01

Fixing authorization lookup code to fix duplicate domain authorizations bug

lemur/plugins/lemur_acme/plugin.py

@@ -54,18 +54,30 @@ class AcmeHandler(object):
             current_app.logger.error(f"Unable to fetch DNS Providers: {e}")
             self.all_dns_providers = []
 
-    def find_dns_challenge(self, host, authorizations):
+    def get_dns_challenges(self, host, authorizations):
+        """Get dns challenges for provided domain"""
+
+        domain_to_validate, is_wildcard = self.strip_wildcard(host)
         dns_challenges = []
         for authz in authorizations:
-            if not authz.body.identifier.value.lower() == host.lower():
+            if not authz.body.identifier.value.lower() == domain_to_validate.lower():
+                continue
+            if is_wildcard and not authz.body.wildcard:
+                continue
+            if not is_wildcard and authz.body.wildcard:
                 continue
             for combo in authz.body.challenges:
                 if isinstance(combo.chall, challenges.DNS01):
                     dns_challenges.append(combo)
+
         return dns_challenges
 
-    def maybe_remove_wildcard(self, host):
+    def strip_wildcard(self, host):
-        return host.replace("*.", "")
+        """Removes the leading *. and returns Host and whether it was removed or not (True/False)"""
+        prefix = "*."
+        if host.startswith(prefix):
+            return host[len(prefix):], True
+        return host, False
 
     def maybe_add_extension(self, host, dns_provider_options):
         if dns_provider_options and dns_provider_options.get(
@@ -86,9 +98,8 @@ class AcmeHandler(object):
         current_app.logger.debug("Starting DNS challenge for {0}".format(host))
 
         change_ids = []
-
+        dns_challenges = self.get_dns_challenges(host, order.authorizations)
-        host_to_validate = self.maybe_remove_wildcard(host)
+        host_to_validate, _ = self.strip_wildcard(host)
-        dns_challenges = self.find_dns_challenge(host_to_validate, order.authorizations)
         host_to_validate = self.maybe_add_extension(
             host_to_validate, dns_provider_options
         )
@@ -325,7 +336,7 @@ class AcmeHandler(object):
                     )
                     dns_provider_options = json.loads(dns_provider.credentials)
                     account_number = dns_provider_options.get("account_id")
-                    host_to_validate = self.maybe_remove_wildcard(authz_record.host)
+                    host_to_validate, _ = self.strip_wildcard(authz_record.host)
                     host_to_validate = self.maybe_add_extension(
                         host_to_validate, dns_provider_options
                     )
@@ -357,7 +368,7 @@ class AcmeHandler(object):
                 dns_provider_options = json.loads(dns_provider.credentials)
                 account_number = dns_provider_options.get("account_id")
                 dns_challenges = authz_record.dns_challenge
-                host_to_validate = self.maybe_remove_wildcard(authz_record.host)
+                host_to_validate, _ = self.strip_wildcard(authz_record.host)
                 host_to_validate = self.maybe_add_extension(
                     host_to_validate, dns_provider_options
                 )

lemur/plugins/lemur_acme/tests/test_acme.py

@@ -23,11 +23,12 @@ class TestAcme(unittest.TestCase):
         }
 
     @patch("lemur.plugins.lemur_acme.plugin.len", return_value=1)
-    def test_find_dns_challenge(self, mock_len):
+    def test_get_dns_challenges(self, mock_len):
         assert mock_len
 
         from acme import challenges
 
+        host = "example.com"
         c = challenges.DNS01()
 
         mock_authz = Mock()
@@ -35,9 +36,18 @@ class TestAcme(unittest.TestCase):
         mock_entry = Mock()
         mock_entry.chall = c
         mock_authz.body.resolved_combinations.append(mock_entry)
-        result = yield self.acme.find_dns_challenge(mock_authz)
+        result = yield self.acme.get_dns_challenges(host, mock_authz)
         self.assertEqual(result, mock_entry)
 
+    def test_strip_wildcard(self):
+        expected = ("example.com", False)
+        result = self.acme.strip_wildcard("example.com")
+        self.assertEqual(expected, result)
+
+        expected = ("example.com", True)
+        result = self.acme.strip_wildcard("*.example.com")
+        self.assertEqual(expected, result)
+
     def test_authz_record(self):
         a = plugin.AuthorizationRecord("host", "authz", "challenge", "id")
         self.assertEqual(type(a), plugin.AuthorizationRecord)
@@ -45,9 +55,9 @@ class TestAcme(unittest.TestCase):
     @patch("acme.client.Client")
     @patch("lemur.plugins.lemur_acme.plugin.current_app")
     @patch("lemur.plugins.lemur_acme.plugin.len", return_value=1)
-    @patch("lemur.plugins.lemur_acme.plugin.AcmeHandler.find_dns_challenge")
+    @patch("lemur.plugins.lemur_acme.plugin.AcmeHandler.get_dns_challenges")
     def test_start_dns_challenge(
-        self, mock_find_dns_challenge, mock_len, mock_app, mock_acme
+        self, mock_get_dns_challenges, mock_len, mock_app, mock_acme
     ):
         assert mock_len
         mock_order = Mock()
@@ -65,7 +75,7 @@ class TestAcme(unittest.TestCase):
         mock_dns_provider.create_txt_record = Mock(return_value=1)
 
         values = [mock_entry]
-        iterable = mock_find_dns_challenge.return_value
+        iterable = mock_get_dns_challenges.return_value
         iterator = iter(values)
         iterable.__iter__.return_value = iterator
         result = self.acme.start_dns_challenge(
@@ -127,12 +137,12 @@ class TestAcme(unittest.TestCase):
     @patch("acme.client.Client")
     @patch("OpenSSL.crypto", return_value="mock_cert")
     @patch("josepy.util.ComparableX509")
-    @patch("lemur.plugins.lemur_acme.plugin.AcmeHandler.find_dns_challenge")
+    @patch("lemur.plugins.lemur_acme.plugin.AcmeHandler.get_dns_challenges")
     @patch("lemur.plugins.lemur_acme.plugin.current_app")
     def test_request_certificate(
         self,
         mock_current_app,
-        mock_find_dns_challenge,
+        mock_get_dns_challenges,
         mock_jose,
         mock_crypto,
         mock_acme,