1#!/usr/local/bin/python2.7
2# start of new fragment overlaps old one
3
4# |--------|
5#     |XXXXX----|
6
7# RFC 5722 drop overlapping fragments
8
9import os
10import threading
11from addr import *
12from scapy.all import *
13
14class Sniff1(threading.Thread):
15	filter = None
16	captured = None
17	packet = None
18	def run(self):
19		self.captured = sniff(iface=SRC_IF, filter=self.filter,
20		    count=1, timeout=3)
21		if self.captured:
22			self.packet = self.captured[0]
23
24dstaddr=sys.argv[1]
25pid=os.getpid()
26eid=pid & 0xffff
27payload="ABCDEFGHIJKLOMNO"
28dummy="01234567"
29packet=IPv6(src=SRC_OUT6, dst=dstaddr)/ICMPv6EchoRequest(id=eid, data=payload)
30fid=pid & 0xffffffff
31frag0=IPv6ExtHdrFragment(nh=58, id=fid, m=1)/str(packet)[40:56]
32frag1=IPv6ExtHdrFragment(nh=58, id=fid, offset=1)/(dummy+str(packet)[56:64])
33pkt0=IPv6(src=SRC_OUT6, dst=dstaddr)/frag0
34pkt1=IPv6(src=SRC_OUT6, dst=dstaddr)/frag1
35eth=[]
36eth.append(Ether(src=SRC_MAC, dst=PF_MAC)/pkt0)
37eth.append(Ether(src=SRC_MAC, dst=PF_MAC)/pkt1)
38
39sniffer = Sniff1();
40sniffer.filter = "ip6 and src %s and dst %s and icmp6" % (dstaddr, SRC_OUT6)
41sniffer.start()
42time.sleep(1)
43sendp(eth, iface=SRC_IF)
44sniffer.join(timeout=5)
45a = sniffer.packet
46
47if a is None:
48	print "no reply"
49	exit(0)
50if a and a.type == ETH_P_IPV6 and \
51    ipv6nh[a.payload.nh] == 'ICMPv6' and \
52    icmp6types[a.payload.payload.type] == 'Echo Reply':
53	id=a.payload.payload.id
54	print "id=%#x" % (id)
55	if id != eid:
56		print "WRONG ECHO REPLY ID"
57		exit(2)
58	data=a.payload.payload.data
59	print "payload=%s" % (data)
60	if data == payload:
61		print "ECHO REPLY"
62		exit(1)
63	print "PAYLOAD!=%s" % (payload)
64	exit(2)
65print "NO ECHO REPLY"
66exit(2)
67