xref: /openbsd-src/regress/sys/netinet/frag/frag_overlimit.py (revision 973a68518aa41045fe1413aa3bbe246a4ca04cc4)
1*973a6851Sbluhm#!/usr/local/bin/python3
2*973a6851Sbluhm
3*973a6851Sbluhmprint("ping fragment at index boundary that cannot be requeued")
4*973a6851Sbluhm
5*973a6851Sbluhm#                               index boundary 4096 |
6*973a6851Sbluhm# |--------------|
7*973a6851Sbluhm#                 ....
8*973a6851Sbluhm#                     |--------------|
9*973a6851Sbluhm#                                                   |--------------|
10*973a6851Sbluhm#                                                                   ....----|
11*973a6851Sbluhm#                                              |XXXX-----|
12*973a6851Sbluhm#                                    |--------------|
13*973a6851Sbluhm
14*973a6851Sbluhm# this should trigger "fragment requeue limit exceeded" log in kernel
15*973a6851Sbluhm
16*973a6851Sbluhmimport os
17*973a6851Sbluhmfrom itertools import chain
18*973a6851Sbluhmfrom addr import *
19*973a6851Sbluhmfrom scapy.all import *
20*973a6851Sbluhm
21*973a6851Sbluhmpid=os.getpid()
22*973a6851Sbluhmeid=pid & 0xffff
23*973a6851Sbluhmpayload=b"ABCDEFGHIJKLMNOP"
24*973a6851Sbluhmdummy=b"01234567"
25*973a6851Sbluhmfragsize=64
26*973a6851Sbluhmboundary=4096
27*973a6851Sbluhmfragnum=int(boundary/fragsize)
28*973a6851Sbluhmpacket=IP(src=LOCAL_ADDR, dst=REMOTE_ADDR)/ \
29*973a6851Sbluhm    ICMP(type='echo-request', id=eid)/ \
30*973a6851Sbluhm    (int((boundary+boundary)/len(payload)) * payload)
31*973a6851Sbluhmfrag=[]
32*973a6851Sbluhmfid=pid & 0xffff
33*973a6851Sbluhmfor i in chain(range(fragnum-1), range(fragnum, fragnum+fragnum-1)):
34*973a6851Sbluhm	frag.append(IP(src=LOCAL_ADDR, dst=REMOTE_ADDR, proto=1, id=fid,
35*973a6851Sbluhm	    frag=(i*fragsize)>>3, flags='MF')/
36*973a6851Sbluhm	    bytes(packet)[20+i*fragsize:20+(i+1)*fragsize])
37*973a6851Sbluhmfrag.append(IP(src=LOCAL_ADDR, dst=REMOTE_ADDR, proto=1, id=fid,
38*973a6851Sbluhm    frag=(boundary+boundary-fragsize)>>3)/
39*973a6851Sbluhm    bytes(packet)[20+boundary+boundary-fragsize:])
40*973a6851Sbluhmfrag.append(IP(src=LOCAL_ADDR, dst=REMOTE_ADDR, proto=1, id=fid,
41*973a6851Sbluhm    frag=(boundary-8)>>3, flags='MF')/
42*973a6851Sbluhm    (dummy+bytes(packet)[20+boundary:20+boundary+8]))
43*973a6851Sbluhmfrag.append(IP(src=LOCAL_ADDR, dst=REMOTE_ADDR, proto=1, id=fid,
44*973a6851Sbluhm    frag=(boundary-fragsize)>>3, flags='MF')/
45*973a6851Sbluhm    bytes(packet)[20+boundary-fragsize:20+boundary])
46*973a6851Sbluhmeth=[]
47*973a6851Sbluhmfor f in frag:
48*973a6851Sbluhm	eth.append(Ether(src=LOCAL_MAC, dst=REMOTE_MAC)/f)
49*973a6851Sbluhm
50*973a6851Sbluhmif os.fork() == 0:
51*973a6851Sbluhm	time.sleep(1)
52*973a6851Sbluhm	for e in eth:
53*973a6851Sbluhm		sendp(e, iface=LOCAL_IF)
54*973a6851Sbluhm		time.sleep(0.001)
55*973a6851Sbluhm	os._exit(0)
56*973a6851Sbluhm
57*973a6851Sbluhmans=sniff(iface=LOCAL_IF, timeout=10, filter=
58*973a6851Sbluhm    "ip and src "+REMOTE_ADDR+" and dst "+LOCAL_ADDR+" and icmp")
59*973a6851Sbluhmfor a in ans:
60*973a6851Sbluhm	if a and a.type == ETH_P_IP and \
61*973a6851Sbluhm	    a.payload.proto == 1 and \
62*973a6851Sbluhm	    a.payload.frag == 0 and \
63*973a6851Sbluhm	    icmptypes[a.payload.payload.type] == 'echo-reply':
64*973a6851Sbluhm		id=a.payload.payload.id
65*973a6851Sbluhm		print("id=%#x" % (id))
66*973a6851Sbluhm		if id != eid:
67*973a6851Sbluhm			print("WRONG ECHO REPLY ID")
68*973a6851Sbluhm			exit(2)
69*973a6851Sbluhm		print("ECHO REPLY")
70*973a6851Sbluhm		exit(1)
71*973a6851Sbluhmprint("no echo reply")
72*973a6851Sbluhmexit(0)
73