Ignore unexpected ICMPv6 Neighbor Discovery - Neighbor Solicitation packets

[csit.git] / resources / traffic_scripts / icmpv6_echo.py

diff --git a/resources/traffic_scripts/icmpv6_echo.py b/resources/traffic_scripts/icmpv6_echo.py
index 4bf573a..a18896b 100755 (executable)
--- a/resources/traffic_scripts/icmpv6_echo.py
+++ b/resources/traffic_scripts/icmpv6_echo.py
@@ -17,13 +17,19 @@
 
 import sys
 import logging
+
+# pylint: disable=no-name-in-module
+# pylint: disable=import-error
 logging.getLogger("scapy.runtime").setLevel(logging.ERROR)
-from resources.libraries.python.PacketVerifier import RxQueue, TxQueue,\
-    checksum_equal
-from resources.libraries.python.TrafficScriptArg import TrafficScriptArg
-from scapy.layers.inet6 import IPv6, ICMPv6ND_NA, ICMPv6NDOptDstLLAddr
-from scapy.layers.inet6 import ICMPv6EchoRequest, ICMPv6EchoReply
+
 from scapy.all import Ether
+from scapy.layers.inet6 import IPv6, ICMPv6ND_NA, ICMPv6ND_NS
+from scapy.layers.inet6 import ICMPv6NDOptDstLLAddr
+from scapy.layers.inet6 import ICMPv6EchoRequest, ICMPv6EchoReply
+
+from resources.libraries.python.PacketVerifier import RxQueue, TxQueue
+from resources.libraries.python.PacketVerifier import checksum_equal
+from resources.libraries.python.TrafficScriptArg import TrafficScriptArg
 
 
 def main():
@@ -43,52 +49,60 @@ def main():
 
     # send ICMPv6 neighbor advertisement message
     pkt_send = (Ether(src=src_mac, dst='ff:ff:ff:ff:ff:ff') /
-                        IPv6(src=src_ip, dst='ff02::1:ff00:2') /
-                        ICMPv6ND_NA(tgt=src_ip, R=0) /
-                        ICMPv6NDOptDstLLAddr(lladdr=src_mac))
+                IPv6(src=src_ip, dst='ff02::1:ff00:2') /
+                ICMPv6ND_NA(tgt=src_ip, R=0) /
+                ICMPv6NDOptDstLLAddr(lladdr=src_mac))
     sent_packets.append(pkt_send)
     txq.send(pkt_send)
 
     # send ICMPv6 echo request
     pkt_send = (Ether(src=src_mac, dst=dst_mac) /
-                        IPv6(src=src_ip, dst=dst_ip) /
-                        ICMPv6EchoRequest(id=echo_id, seq=echo_seq))
+                IPv6(src=src_ip, dst=dst_ip) /
+                ICMPv6EchoRequest(id=echo_id, seq=echo_seq))
     sent_packets.append(pkt_send)
     txq.send(pkt_send)
 
     # receive ICMPv6 echo reply
-    ether = rxq.recv(2, sent_packets)
-    if ether is None:
-        raise RuntimeError('ICMPv6 echo reply Rx timeout')
+    while True:
+        ether = rxq.recv(2, sent_packets)
+        if ether is None:
+            raise RuntimeError('ICMPv6 echo reply Rx timeout')
+
+        if ether.haslayer(ICMPv6ND_NS):
+            # read another packet in the queue if the current one is ICMPv6ND_NS
+            continue
+        else:
+            # otherwise process the current packet
+            break
 
     if not ether.haslayer(IPv6):
-        raise RuntimeError('Unexpected packet with no IPv6 received {0}'.format(
-            ether.__repr__()))
+        raise RuntimeError('Unexpected packet with no IPv6 received {0}'.
+                           format(ether.__repr__()))
 
-    ipv6 = ether['IPv6']
+    ipv6 = ether[IPv6]
 
     if not ipv6.haslayer(ICMPv6EchoReply):
-        raise RuntimeError(
-            'Unexpected packet with no IPv6 ICMP received {0}'.format(
-                ipv6.__repr__()))
+        raise RuntimeError('Unexpected packet with no ICMPv6 echo reply '
+                           'received {0}'.format(ipv6.__repr__()))
 
-    icmpv6 = ipv6['ICMPv6 Echo Reply']
+    icmpv6 = ipv6[ICMPv6EchoReply]
 
     # check identifier and sequence number
     if icmpv6.id != echo_id or icmpv6.seq != echo_seq:
-        raise RuntimeError(
-            'Invalid ICMPv6 echo reply received ID {0} seq {1} should be ' \
-            'ID {2} seq {3}'.format(icmpv6.id, icmpv6.seq, echo_id, echo_seq))
+        raise RuntimeError('Invalid ICMPv6 echo reply received ID {0} seq {1} '
+                           'should be ID {2} seq {3}'.
+                           format(icmpv6.id, icmpv6.seq, echo_id, echo_seq))
 
     # verify checksum
     cksum = icmpv6.cksum
     del icmpv6.cksum
     tmp = ICMPv6EchoReply(str(icmpv6))
     if not checksum_equal(tmp.cksum, cksum):
-        raise RuntimeError(
-            'Invalid checksum {0} should be {1}'.format(cksum, tmp.cksum))
+        raise RuntimeError('Invalid checksum {0} should be {1}'.
+                           format(cksum, tmp.cksum))
 
     sys.exit(0)
 
+
 if __name__ == "__main__":
     main()