+#!/usr/bin/env python
+# Copyright (c) 2016 Cisco and/or its affiliates.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Router advertisement check script."""
+
+import sys
+import ipaddress
+
+from resources.libraries.python.PacketVerifier import RxQueue
+from resources.libraries.python.TrafficScriptArg import TrafficScriptArg
+
+
+def mac_to_ipv6_linklocal(mac):
+ """Transfer MAC address into specific link-local IPv6 address.
+
+ :param mac: MAC address to be transferred.
+ :type mac: str
+ :return: IPv6 link-local address.
+ :rtype: str
+ """
+ # Remove the most common delimiters: dots, dashes, etc.
+ mac_value = int(mac.translate(None, ' .:-'), 16)
+
+ # Split out the bytes that slot into the IPv6 address
+ # XOR the most significant byte with 0x02, inverting the
+ # Universal / Local bit
+ high2 = mac_value >> 32 & 0xffff ^ 0x0200
+ high1 = mac_value >> 24 & 0xff
+ low1 = mac_value >> 16 & 0xff
+ low2 = mac_value & 0xffff
+
+ return 'fe80::{:04x}:{:02x}ff:fe{:02x}:{:04x}'.format(
+ high2, high1, low1, low2)
+
+
+def main():
+ """Check packets on specific port and look for the Router Advertisement
+ part.
+ """
+
+ args = TrafficScriptArg(['src_mac'])
+
+ rx_if = args.get_arg('rx_if')
+ src_mac = args.get_arg('src_mac')
+ rxq = RxQueue(rx_if)
+
+ ether = rxq.recv(8)
+
+ # Check whether received packet contains layer RA and check other values
+ if ether is None:
+ raise RuntimeError('ICMP echo Rx timeout')
+
+ if not ether.haslayer('ICMPv6ND_RA'):
+ raise RuntimeError('Not an RA packet received {0}'
+ .format(ether.__repr__()))
+
+ address = ipaddress.IPv6Address(unicode(ether['IPv6'].src))
+ link_local = ipaddress.IPv6Address(unicode(mac_to_ipv6_linklocal(src_mac)))
+
+ if address != link_local:
+ raise RuntimeError(
+ 'Source address ({0}) not matching link local address({1})'.format(
+ address, link_local))
+
+ if ether['IPv6'].hlim != 255:
+ raise RuntimeError('Hop limit not correct: {0}!=255'.format(
+ ether['IPv6'].hlim))
+
+ ra_code = ether['ICMPv6 Neighbor Discovery - Router Advertisement'].code
+ if ra_code != 0:
+ raise RuntimeError('ICMP code: {0} not correct. '.format(ra_code))
+
+ sys.exit(0)
+
+if __name__ == "__main__":
+ main()
Code Review / csit.git / commitdiff