Changing the source on incoming messages

Yaakov_Metzger@xxxxxxxxxx (Metzger Kobi) · Wed, 9 Oct 2002 15:06:58 +0200

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Hi,

I am quite new to the netfilter buisiness, however I have the following
problem that I am not sure wether i can solve using iptables.

I would like to fool an aplication in my computer so while it thinks it
communicates with x.y.z.w it will actually connect to a.b.c.d. (port number
unchanged).

I succeeded in diverting the outgoing messages using DNAT on teh OUTPUT. The
problem is that I could not change the source address on the incoming
messages,
 and the aplication won't work if the source is different. The SNAT cannot
be put on the incoming messages (while DNAT can be put
on outgoing messages).

Is there any other way to do this without touching other components on the
net, and without touching the application.

Coby.

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<TITLE>Changing the source on incoming messages</TITLE>
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<P><FONT SIZE=3D2 FACE=3D"Arial">Hi,</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">I am quite new to the netfilter =
buisiness, however I have the following problem that I am not sure =
wether i can solve using iptables.</FONT></P>

I would like to fool an aplication in =
my computer so while it thinks it communicates with x.y.z.w it will =
actually connect to a.b.c.d. (port number unchanged).

I succeeded in diverting the outgoing =
messages using DNAT on teh OUTPUT. The problem is that I could not =
change the source address on the incoming messages,

&nbsp;and the aplication won't work if =
the source is different. The SNAT cannot be put on the incoming =
messages (while DNAT can be put

<P><FONT SIZE=3D2 FACE=3D"Arial">on outgoing messages).</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Is there any other way to do this =
without touching other components on the net, and without touching the =
application.</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Coby.</FONT>
</P>

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