Separate files needing GPL license

[csit.git] / GPL / traffic_scripts / policer.py

diff --git a/GPL/traffic_scripts/policer.py b/GPL/traffic_scripts/policer.py
new file mode 100644 (file)
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+++ b/GPL/traffic_scripts/policer.py
@@ -0,0 +1,122 @@
+#!/usr/bin/env python3
+
+# Copyright (c) 2020 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.
+
+"""Traffic script for IPsec verification."""
+
+import sys
+import logging
+
+from ipaddress import ip_address
+from scapy.layers.l2 import Ether
+from scapy.layers.inet import IP, TCP
+from scapy.layers.inet6 import IPv6, ICMPv6ND_NS
+from scapy.packet import Raw
+
+from .TrafficScriptArg import TrafficScriptArg
+from .PacketVerifier import RxQueue, TxQueue
+
+
+def check_ipv4(pkt_recv, dscp):
+    """Check received IPv4 IPsec packet.
+
+    :param pkt_recv: Received packet to verify.
+    :param dscp: DSCP value to check.
+    :type pkt_recv: scapy.Ether
+    :type dscp: int
+    :raises RuntimeError: If received packet is invalid.
+    """
+    if not pkt_recv.haslayer(IP):
+        raise RuntimeError(f"Not an IPv4 packet received: {pkt_recv!r}")
+
+    rx_dscp = pkt_recv[IP].tos >> 2
+    if rx_dscp != dscp:
+        raise RuntimeError(f"Invalid DSCP {rx_dscp} should be {dscp}")
+
+    if not pkt_recv.haslayer(TCP):
+        raise RuntimeError(f"Not a TCP packet received: {pkt_recv!r}")
+
+
+def check_ipv6(pkt_recv, dscp):
+    """Check received IPv6 IPsec packet.
+
+    :param pkt_recv: Received packet to verify.
+    :param dscp: DSCP value to check.
+    :type pkt_recv: scapy.Ether
+    :type dscp: int
+    :raises RuntimeError: If received packet is invalid.
+    """
+    if not pkt_recv.haslayer(IPv6):
+        raise RuntimeError(f"Not an IPv6 packet received: {pkt_recv!r}")
+
+    rx_dscp = pkt_recv[IPv6].tc >> 2
+    if rx_dscp != dscp:
+        raise RuntimeError(f"Invalid DSCP {rx_dscp} should be {dscp}")
+
+    if not pkt_recv.haslayer(TCP):
+        raise RuntimeError(f"Not a TCP packet received: {pkt_recv!r}")
+
+
+# TODO: Pylint says too-many-locals and too-many-statements. Refactor!
+def main():
+    """Send and receive TCP packet."""
+    args = TrafficScriptArg(
+        [u"src_mac", u"dst_mac", u"src_ip", u"dst_ip", u"dscp"]
+    )
+
+    rxq = RxQueue(args.get_arg(u"rx_if"))
+    txq = TxQueue(args.get_arg(u"tx_if"))
+
+    src_mac = args.get_arg(u"src_mac")
+    dst_mac = args.get_arg(u"dst_mac")
+    src_ip = args.get_arg(u"src_ip")
+    dst_ip = args.get_arg(u"dst_ip")
+    dscp = int(args.get_arg(u"dscp"))
+
+    ip_layer = IPv6 if ip_address(src_ip).version == 6 else IP
+
+    sent_packets = list()
+    pkt_send = (Ether(src=src_mac, dst=dst_mac) /
+                ip_layer(src=src_ip, dst=dst_ip) /
+                TCP())
+
+    pkt_send /= Raw()
+    sent_packets.append(pkt_send)
+    txq.send(pkt_send)
+
+    while True:
+        pkt_recv = rxq.recv(2, sent_packets)
+        if pkt_recv is None:
+            raise RuntimeError(u"ICMPv6 echo reply Rx timeout")
+
+        if pkt_recv.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 pkt_recv is None:
+        raise RuntimeError(u"Rx timeout")
+
+    if ip_layer == IP:
+        check_ipv4(pkt_recv, dscp)
+    else:
+        check_ipv6(pkt_recv, dscp)
+
+    sys.exit(0)
+
+
+if __name__ == u"__main__":
+    main()