Re: [sr-dev] force_rtp_proxy() usage with IP that is not natively homed

Sorry for cross-posting from k-users; was hoping maybe someone here has some insights, as rtpproxy is a sparsely documented topic. -------- Original Message -------- Subject: force_rtp_proxy() usage with IP that is not natively homed Date: Mon, 02 Nov 2009 01:23:40 -0500 From: Alex Balashov <abalashov(a)evaristesys.com> To: kamailio <users(a)lists.kamailio.org> Greetings, Please excuse the apparent silliness of this request, but I am curious  if there is a combination of flags passed to force_rtp_proxy() and/or rtpproxy invocation options that can allow force_rtp_proxy() to substitute an SDP endpoint IP that is not a physical device/interface on the host on which rtpproxy is running? Let me explain further: 1. I have a host with a single network interface that has private IP 192.168.1.254. 2. I am receiving an inbound call from outside the network, coming in on a public IP address 4.4.4.4 that is a 1-to-1 DNAT/SNAT to 192.168.1.254. 3. The call is forwarded to a PBX on the same LAN as the native interface, e.g. 192.168.1.250. 4. I would like to set up SDP in such a way that 192.168.1.250 sendsmedia to the 192.168.1.254 interface while the outside host initiating the call sends its media to 4.4.4.4. Under normal circumstances in which both the public and private interface were physically present on the machine, this would call for the use of "bridging" mode (rtpproxy invoked with -l 4.4.4.4/192.168.1.254 and use of "ie" and "ei" flags with force_rtp_proxy() - we have previously established that rtpproxy_offer/answer do not actually seem to work as advertised). But is it possible to "bridge" to an IP that is not routed to the box? I expected that force_rtp_proxy()'s second parameter - ip_address - would do this.  However, this does not appear to let me override the SDP endpoint with any IP address I want;  it seems that I am still limited to choosing from those IPs physically available on the rtpproxy host.  I would guess that this is because ip_address is passed as a parameter through rtpproxy's control API socket and is validated by rtpproxy itself, and if it is not a local existing address, is overridden with one that is. Is there a clever combination of flags that can be used to accomplish this, or is it a lost cause? Thanks! -- Alex Balashov - Principal Evariste Systems Web     : http://www.evaristesys.com/ Tel     : (+1) (678) 954-0670 Direct  : (+1) (678) 954-0671 -- Alex Balashov - Principal Evariste Systems Web     : http://www.evaristesys.com/ Tel     : (+1) (678) 954-0670 Direct  : (+1) (678) 954-0671 _______________________________________________ sr-dev mailing list sr-dev(a)lists.sip-router.org http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-dev