dnsdist: Add a regression test for the DoH concurrent conn limit

diff --git a/regression-tests.dnsdist/test_DOH.py b/regression-tests.dnsdist/test_DOH.py
index cd12c96133d215b4825cea91a9760fa8d04cff0c..9fcb4b52977a1753bb349a955144519b39c6725c 100644 (file)
--- a/regression-tests.dnsdist/test_DOH.py
+++ b/regression-tests.dnsdist/test_DOH.py
@@ -1329,3 +1329,57 @@ class TestDOHForwardedToTCPOnly(DNSDistDOHTest):
         receivedQuery.id = query.id
         self.assertEqual(receivedQuery, query)
         self.assertEqual(receivedResponse, response)
+
+class TestDOHLimits(DNSDistDOHTest):
+    _serverName = 'tls.tests.dnsdist.org'
+    _caCert = 'ca.pem'
+    _dohServerPort = 8443
+    _dohBaseURL = ("https://%s:%d/" % (_serverName, _dohServerPort))
+    _serverKey = 'server.key'
+    _serverCert = 'server.chain'
+    _maxTCPConnsPerClient = 3
+    _config_template = """
+    newServer{address="127.0.0.1:%s"}
+    addDOHLocal("127.0.0.1:%s", "%s", "%s", { "/" })
+    setMaxTCPConnectionsPerClient(%s)
+    """
+    _config_params = ['_testServerPort', '_dohServerPort', '_serverCert', '_serverKey', '_maxTCPConnsPerClient']
+
+    def testConnsPerClient(self):
+        """
+        DoH Limits: Maximum number of conns per client
+        """
+        name = 'maxconnsperclient.doh.tests.powerdns.com.'
+        query = dns.message.make_query(name, 'A', 'IN')
+        url = self.getDOHGetURL(self._dohBaseURL, query)
+        conns = []
+
+        for idx in range(self._maxTCPConnsPerClient + 1):
+            conn = self.openDOHConnection(self._dohServerPort, self._caCert, timeout=2.0)
+            conn.setopt(pycurl.URL, url)
+            conn.setopt(pycurl.RESOLVE, ["%s:%d:127.0.0.1" % (self._serverName, self._dohServerPort)])
+            conn.setopt(pycurl.SSL_VERIFYPEER, 1)
+            conn.setopt(pycurl.SSL_VERIFYHOST, 2)
+            conn.setopt(pycurl.CAINFO, self._caCert)
+            conns.append(conn)
+
+        count = 0
+        failed = 0
+        for conn in conns:
+            try:
+                data = conn.perform_rb()
+                rcode = conn.getinfo(pycurl.RESPONSE_CODE)
+                count = count + 1
+            except:
+                failed = failed + 1
+
+        for conn in conns:
+            conn.close()
+
+        # wait a bit to be sure that dnsdist closed the connections
+        # and decremented the counters on its side, otherwise subsequent
+        # connections will be dropped
+        time.sleep(1)
+
+        self.assertEqual(count, self._maxTCPConnsPerClient)
+        self.assertEqual(failed, 1)