Ypghost should be self-contained in one C file, other than the libpcap
portable packet capturing library.

If you haven't got libpcap use archie to find it, or try getting the
file libpcap-0.0.6.tar.Z from the top level directory of anonymous ftp
at ftp.ee.lbl.gov.  Unfortunately development seems to have stopped on
libpcap and the linux version of libpcap isn't incorporated into the
standard release, so you'll probably have to get it from the patched
version of tcpdump for linux, if you haven't already got it from my
page.  You almost certainly want to get the latest version of libpcap.
Naturally you'll need to follow the instructions that come with
libpcap that tells you how to compile it.

Ypghost also needs a proper 4.4BSDlite style implementation of raw
sockets in order to be able to spoof the source address in the IP
header.  Old kernels such as SunOS 4.1.3 and all current Linux kernels
will set the source address to the address of the interface (i.e. it
wont work).  I expect linux to be fixed fairly soon but until then
see the file LINUXMOD that tells you how to modify the kernel.

Compiling just basically consists of typing something like:

cc -o ypghost ypghost.c -lpcap

Where,

  cc		is a sensible ANSI C compiler, such as gcc, or /usr/ucb/cc
		on SunOS 5.4

  ypghost.c	is the version of ypghost.c you have, such as ypghost001.c

  -lpcap	specifies to use the libpcap.a library.  If you have not
		got this *installed* on your system, you'll have to also
		use some more options to specify extra directorys that
		the compiler should look in for librarys and header files.

On SunOS 5.4 you might also need to specify some extra librarys with
-lsocket and possibly -lnsl.

For example, on SunOS 5.4, if you had the libpcap.a and pcap.h files in
the directory libpcap in the parent directory (i.e. ../libpcap), you
might try:

/usr/ucb/cc -I../libpcap -L../libpcap -o ypghost ypghost.c -lpcap -lsocket

I'm sure you'll work it out.

Finally, just in case you haven't read this elsewhere, I'm not responsible
for anything ypghost does.

Arny - cs6171@scitsc.wlv.ac.uk

			http://www.scit.wlv.ac.uk/~cs6171/hack/index.html

