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<DIV><FONT face=Arial size=2>Hi,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I am new to SER and I am looking for how to
determine whether the caller and the callee are behind NAT. I found some example
code from Zeus. But I do not understand how I can distinguished whether the
caller is the caller and the callee is the callee. Here is the
code:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial
size=2>/**************************************************************************************************************************/</FONT></DIV>
<DIV><PRE>Jan,
See below. Also, always CC the list so that other people can help you.
Zeus
><I> >
</I>><I> > Flag 4 is set when the caller is behind NAT.
</I>><I> > Flag 5 is set when the callee is behind NAT.
</I>
><I> Would you be so kind and tell me how do you test messages to
</I>><I> set these
</I>><I> flags?
</I>
/*
Check for UAC behind NAT
This is done by nat_uac_test("7") which checks for
1. RFC 1918 address in Contact - 01
2. different src_ip and Via header - 02
3. RFC1918 in Top Via - 04
*/
</PRE><PRE>/*********************************************************************************************************************</PRE><PRE>1. Right here - it seems to me that if both the caller and the callee are behind NAT. It will be flag as (4) and do the force_rport.</PRE><PRE>*********************************************************************************************************************/</PRE><PRE> if (nat_uac_test("3")) { /* 1 + 2 = 3 */
xlog("L_NOTICE", "%rm: Client is behind NAT\n");
setflag(4); /* Flag it's a nated R-URI */
if (method=="REGISTER" || !search("^Record-Route:")) {
force_rport();
if (!method=="MESSAGE") { /* MESSAGE has no Contact header, see RFC 3428 */
fix_nated_contact();
};
};
} else {
xlog("L_NOTICE", "%rm: Client is not behind a NAT\n");
};</PRE><PRE>... Other checking ...</PRE><PRE>/********************************************************************************************************************</PRE><PRE>2. Then down here - it seems to me that the caller and the callee will be mark as flag 5. Then save into the location. Later on, how can I tell if</PRE><PRE>the packet comes to SER is a caller or the callee ????. I could not understand this.</PRE><PRE>********************************************************************************************************************/
if (method=="REGISTER") {
if (isflagset(4)) {
setflag(5); /* Turn on NAT Ping and flag it as a NAT callee */
};
if (!save("location")) {
xlog("L_ERR", "%rm: Failed\n");
sl_reply_error();
};
break;
};
/********************************************************************************************************************/
</PRE><PRE>I am trying to make SER works with two UAs behind a same NAT. Any help would be very appreciated.</PRE><PRE> </PRE><PRE>Regards,</PRE><PRE>Trong
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