Test the ECN observer functions

pathspider/observer/tcp.py

@@ -5,7 +5,7 @@
 TCP_SYN = 0x02
 
 TCP_SEC = ( TCP_SYN | TCP_ECE | TCP_CWR )
-TCP_SAEW = (TCP_SYN | TCP_ACK | TCP_ECE | TCP_CWR)
+TCP_SAEC = (TCP_SYN | TCP_ACK | TCP_ECE | TCP_CWR)
 TCP_SAE = (TCP_SYN | TCP_ACK | TCP_ECE)
 
 def tcp_setup(rec, ip):

pathspider/plugins/ecn.py

@@ -19,7 +19,7 @@
 from pathspider.observer.tcp import tcp_handshake
 from pathspider.observer.tcp import tcp_complete
 from pathspider.observer.tcp import TCP_SAE
-from pathspider.observer.tcp import TCP_SAEW
+from pathspider.observer.tcp import TCP_SAEC
 
 Connection = collections.namedtuple("Connection", ["client", "port", "state", "tstart"])
 SpiderRecord = collections.namedtuple("SpiderRecord", ["ip", "rport", "port",
@@ -41,16 +41,16 @@ def ecn_setup(rec, ip):
     return True
 
 def ecn_code(rec, ip, rev):
-    EZ = 0x01
-    EO = 0x02
+    EZ = 0x02
+    EO = 0x01
     CE = 0x03
 
-    if (ip.traffic_class & EZ == EZ):
+    if (ip.traffic_class & CE == EZ):
         if rev:
             rec['rev_ez'] = True
         else:
             rec['fwd_ez'] = True
-    if (ip.traffic_class & EO == EO):
+    if (ip.traffic_class & CE == EO):
         if rev:
             rec['rev_eo'] = True
         else:
@@ -190,7 +190,7 @@ def combine_flows(self, flow):
                 cond_conn = 'ecn.connectivity.offline'
             conditions.append(cond_conn)
 
-            if flows[1]['rev_syn_flags'] & TCP_SAEW == TCP_SAE:
+            if flows[1]['rev_syn_flags'] & TCP_SAEC == TCP_SAE:
                 negotiated = True
                 conditions.append('ecn.negotiated')
             else:

tests/test_observer_ecn.py

@@ -0,0 +1,93 @@
+
+import logging
+import queue
+import threading
+
+import nose
+
+from pathspider.base import SHUTDOWN_SENTINEL
+from pathspider.observer import Observer
+
+from pathspider.observer import basic_flow
+from pathspider.observer.tcp import TCP_SEC
+from pathspider.observer.tcp import TCP_SAE
+from pathspider.plugins.ecn import ECN
+
+def test_observer_ecn():
+    try:
+        import plt # libtrace may not be available
+    except:
+        raise nose.SkipTest
+
+    lturi = "pcap:tests/testdata/tcp_ecn.pcap"
+
+    logging.getLogger().setLevel(logging.INFO)
+
+    spider = ECN(1, lturi, None)
+    o = spider.create_observer()
+    q = queue.Queue()
+    t = threading.Thread(target=o.run_flow_enqueuer,
+                         args=(q,),
+                         daemon=True)
+    t.start()
+
+    flows = []
+    while True:
+        f = q.get()
+        if f == SHUTDOWN_SENTINEL:
+            break
+        flows.append(f)
+
+    assert len(flows) == 1
+
+    flow = flows[0]
+    assert flow['sp'] == 46557
+    assert flow['dp'] == 80
+    assert flow['fwd_syn_flags'] == TCP_SEC
+    assert flow['rev_syn_flags'] == TCP_SAE
+    assert flow['tcp_connected'] == True
+    assert flow['fwd_fin'] == True
+    assert flow['rev_fin'] == True
+    assert flow['fwd_rst'] == False
+    assert flow['rev_rst'] == False
+    assert flow['fwd_ez'] == True
+    assert flow['rev_ez'] == True
+    assert flow['fwd_eo'] == False
+    assert flow['rev_eo'] == False
+    assert flow['fwd_ce'] == False
+    assert flow['rev_ce'] == True
+
+def test_observer_ecn_partial_flow():
+    try:
+        import plt # libtrace may not be available
+    except:
+        raise nose.SkipTest
+
+    lturi = "pcap:tests/testdata/tcp_http.pcap"
+
+    logging.getLogger().setLevel(logging.INFO)
+
+    spider = ECN(1, lturi, None)
+    o = spider.create_observer()
+    q = queue.Queue()
+    t = threading.Thread(target=o.run_flow_enqueuer,
+                         args=(q,),
+                         daemon=True)
+    t.start()
+
+    flows = []
+    while True:
+        f = q.get()
+        if f == SHUTDOWN_SENTINEL:
+            break
+        flows.append(f)
+
+    assert len(flows) == 3
+
+    for flow in flows:
+        assert flow['fwd_ez'] == False
+        assert flow['rev_ez'] == False
+        assert flow['fwd_eo'] == False
+        assert flow['rev_eo'] == False
+        assert flow['fwd_ce'] == False
+        assert flow['rev_ce'] == False