3 # Copyright (c) 2016 Cisco and/or its affiliates.
4 # Licensed under the Apache License, Version 2.0 (the "License");
5 # you may not use this file except in compliance with the License.
6 # You may obtain a copy of the License at:
8 # http://www.apache.org/licenses/LICENSE-2.0
10 # Unless required by applicable law or agreed to in writing, software
11 # distributed under the License is distributed on an "AS IS" BASIS,
12 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 # See the License for the specific language governing permissions and
14 # limitations under the License.
16 from scapy.all import Ether, IP, ICMP
17 from resources.libraries.python.PacketVerifier \
18 import Interface, create_gratuitous_arp_request, auto_pad
19 from resources.libraries.python.TrafficScriptArg import TrafficScriptArg
22 def check_ttl(ttl_begin, ttl_end, ttl_diff):
23 if ttl_begin != ttl_end + ttl_diff:
25 "TTL changed from {} to {} but decrease by {} expected"
26 .format(ttl_begin, ttl_end, ttl_diff))
29 def ckeck_packets_equal(pkt_send, pkt_recv):
30 pkt_send_raw = auto_pad(pkt_send)
31 pkt_recv_raw = auto_pad(pkt_recv)
32 if pkt_send_raw != pkt_recv_raw:
33 print "Sent: {}".format(pkt_send_raw.encode('hex'))
34 print "Received: {}".format(pkt_recv_raw.encode('hex'))
36 Ether(pkt_send_raw).show2()
38 Ether(pkt_recv_raw).show2()
39 raise Exception("Sent packet doesn't match received packet")
43 args = TrafficScriptArg(['src_mac', 'dst_mac', 'src_ip', 'dst_ip',
44 'hops', 'first_hop_mac', 'is_dst_tg'])
46 src_if_name = args.get_arg('tx_if')
47 dst_if_name = args.get_arg('rx_if')
48 is_dst_tg = True if args.get_arg('is_dst_tg') == 'True' else False
50 src_mac = args.get_arg('src_mac')
51 first_hop_mac = args.get_arg('first_hop_mac')
52 dst_mac = args.get_arg('dst_mac')
53 src_ip = args.get_arg('src_ip')
54 dst_ip = args.get_arg('dst_ip')
55 hops = int(args.get_arg('hops'))
57 if is_dst_tg and (src_if_name == dst_if_name):
58 raise Exception("Source interface name equals destination interface name")
60 src_if = Interface(src_if_name)
61 src_if.send_pkt(str(create_gratuitous_arp_request(src_mac, src_ip)))
63 dst_if = Interface(dst_if_name)
64 dst_if.send_pkt(str(create_gratuitous_arp_request(dst_mac, dst_ip)))
66 pkt_req_send = (Ether(src=src_mac, dst=first_hop_mac) /
67 IP(src=src_ip, dst=dst_ip) /
69 src_if.send_pkt(pkt_req_send)
72 pkt_req_recv = dst_if.recv_pkt()
73 if pkt_req_recv is None:
74 raise Exception('Timeout waiting for packet')
76 check_ttl(pkt_req_send[IP].ttl, pkt_req_recv[IP].ttl, hops)
77 pkt_req_send_mod = pkt_req_send.copy()
78 pkt_req_send_mod[IP].ttl = pkt_req_recv[IP].ttl
79 del pkt_req_send_mod[IP].chksum # update checksum
80 ckeck_packets_equal(pkt_req_send_mod[IP], pkt_req_recv[IP])
82 pkt_resp_send = (Ether(src=dst_mac, dst=pkt_req_recv.src) /
83 IP(src=dst_ip, dst=src_ip) /
84 ICMP(type=0)) # echo-reply
85 dst_if.send_pkt(pkt_resp_send)
87 pkt_resp_recv = src_if.recv_pkt()
88 if pkt_resp_recv is None:
89 raise Exception('Timeout waiting for packet')
92 check_ttl(pkt_resp_send[IP].ttl, pkt_resp_recv[IP].ttl, hops)
93 pkt_resp_send_mod = pkt_resp_send.copy()
94 pkt_resp_send_mod[IP].ttl = pkt_resp_recv[IP].ttl
95 del pkt_resp_send_mod[IP].chksum # update checksum
96 ckeck_packets_equal(pkt_resp_send_mod[IP], pkt_resp_recv[IP])
99 if __name__ == "__main__":