1#!/usr/local/bin/python2.7
2# end of new fragment overlaps old one
3
4#     |XXXXX----|
5# |--------|
6
7# RFC 5722 drop overlapping fragments
8
9import os
10from addr import *
11from scapy.all import *
12
13dstaddr=sys.argv[1]
14pid=os.getpid()
15payload="ABCDEFGHIJKLOMNO"
16dummy="01234567"
17packet=IPv6(src=SRC_OUT6, dst=dstaddr)/ICMPv6EchoRequest(id=pid, data=payload)
18frag0=IPv6ExtHdrFragment(nh=58, id=pid, m=1)/str(packet)[40:56]
19frag1=IPv6ExtHdrFragment(nh=58, id=pid, offset=1)/(dummy+str(packet)[56:64])
20pkt0=IPv6(src=SRC_OUT6, dst=dstaddr)/frag0
21pkt1=IPv6(src=SRC_OUT6, dst=dstaddr)/frag1
22eth=[]
23eth.append(Ether(src=SRC_MAC, dst=PF_MAC)/pkt1)
24eth.append(Ether(src=SRC_MAC, dst=PF_MAC)/pkt0)
25
26if os.fork() == 0:
27	time.sleep(1)
28	sendp(eth, iface=SRC_IF)
29	os._exit(0)
30
31ans=sniff(iface=SRC_IF, timeout=3, filter=
32    "ip6 and src "+dstaddr+" and dst "+SRC_OUT6+" and icmp6")
33if len(ans) == 0:
34	print "no reply"
35	exit(0)
36a=ans[0]
37if a and a.type == ETH_P_IPV6 and \
38    ipv6nh[a.payload.nh] == 'ICMPv6' and \
39    icmp6types[a.payload.payload.type] == 'Echo Reply':
40	id=a.payload.payload.id
41	print "id=%#x" % (id)
42	if id != pid:
43		print "WRONG ECHO REPLY ID"
44		exit(2)
45	data=a.payload.payload.data
46	print "payload=%s" % (data)
47	if data == payload:
48		print "ECHO REPLY"
49		exit(1)
50	print "PAYLOAD!=%s" % (payload)
51	exit(2)
52print "NO ECHO REPLY"
53exit(2)
54