1#!/usr/local/bin/python2.7
2
3print "ping6 fragment that overlaps the second fragment with the head"
4
5# |----|
6#      |----|
7#      |XXXXXXXXX|
8#           |----|
9
10import os
11from addr import *
12from scapy.all import *
13
14pid=os.getpid()
15eid=pid & 0xffff
16payload="ABCDEFGHIJKLMNOP"
17dummy="0123456701234567"
18packet=IPv6(src=LOCAL_ADDR6, dst=REMOTE_ADDR6)/ \
19    ICMPv6EchoRequest(id=eid, data=payload)
20frag=[]
21fid=pid & 0xffffffff
22frag.append(IPv6ExtHdrFragment(nh=58, id=fid, m=1)/str(packet)[40:48])
23frag.append(IPv6ExtHdrFragment(nh=58, id=fid, offset=1, m=1)/str(packet)[48:56])
24frag.append(IPv6ExtHdrFragment(nh=58, id=fid, offset=1)/dummy)
25frag.append(IPv6ExtHdrFragment(nh=58, id=fid, offset=2)/str(packet)[56:64])
26eth=[]
27for f in frag:
28	pkt=IPv6(src=LOCAL_ADDR6, dst=REMOTE_ADDR6)/f
29	eth.append(Ether(src=LOCAL_MAC, dst=REMOTE_MAC)/pkt)
30
31if os.fork() == 0:
32	time.sleep(1)
33	sendp(eth, iface=LOCAL_IF)
34	os._exit(0)
35
36ans=sniff(iface=LOCAL_IF, timeout=3, filter=
37    "ip6 and src "+REMOTE_ADDR6+" and dst "+LOCAL_ADDR6+" and icmp6")
38for a in ans:
39	if a and a.type == ETH_P_IPV6 and \
40	    ipv6nh[a.payload.nh] == 'ICMPv6' and \
41	    icmp6types[a.payload.payload.type] == 'Echo Reply':
42		id=a.payload.payload.id
43		print "id=%#x" % (id)
44		if id != eid:
45			print "WRONG ECHO REPLY ID"
46			exit(2)
47		data=a.payload.payload.data
48		print "payload=%s" % (data)
49		if data == payload:
50			print "ECHO REPLY"
51			exit(1)
52		print "PAYLOAD!=%s" % (payload)
53		exit(2)
54print "no echo reply"
55exit(0)
56