1
2Building fragrouter
3-------------------
4
5To build fragrouter on a supported platform:
6
7	% ./configure ; make
8
9If you get it to work on a platform not listed above, please let us
10know!
11
12Installing fragrouter
13---------------------
14
15To install fragrouter, as root:
16
17	# make install
18
19This will install the fragrouter binary and man page (by default,
20/usr/local/sbin/fragrouter and /usr/local/man/man8/fragrouter.8).
21
22Running fragrouter
23------------------
24
25Fragrouter can not be used to fragment traffic originating from the
26same machine on which it runs. This is by design, to help prevent
27abuse of this software.
28
29To fragment all attacks going from host hax0r to host victim, via
30fragrouter running on host middleman, do the following:
31
321. On host hax0r, set a host route to victim through middleman:
33
34	# route add victim middleman
35	add host victim: gateway middleman
36
372. Start fragrouter running on host middleman:
38
39	# fragrouter -F1
40	fragrouter: frag-1 started
41
423. Send attacks normally from hax0r to victim. Fragrouter on middleman
43   will accept traffic from hax0r, fragment it, and forward the
44   transformed stream to victim. The return path will NOT go through
45   the fragrouter.
46
474. To stop fragrouter, hit ^C (control-c).
48
49Known Problems
50--------------
51
52Fragrouter will NOT fragment traffic originating from the host it's
53running on. This was a conscious design decision, to help prevent
54abuse of this software.
55
56Fragrouter and the attacking machine need to be on the same network
57segment (behind a router), while the victim host needs to be on a
58separate network entirely. This is because the route from the attacker
59to the victim is asymmetric when fragrouter is running.
60
61The machine running fragrouter should not be running a sniffer (or any
62other program which sets the interface in promiscuous mode). Although
63fragrouter will still work, the latency in resending packets will be
64much worse.
65
66This is only proof-of-concept test code. Works for me. YMMV.
67
68Troubleshooting
69---------------
70
71Fragrouter will print a tcpdump-style output line for every
72packet/fragment it forwards. If you aren't seeing ANY output,
73fragrouter isn't accepting any packets.
74
75To aid in debugging, recompile fragrouter with -DDEBUG added to the
76CFLAGS line of the auto-generated top-level Makefile. This will make
77fragrouter's output a bit more verbose.
78
79
80---
81$Id: INSTALL,v 1.8 1999/05/27 04:18:45 dugsong Exp $
82