Re: [Users] Checking Request-URI

Andreas Sikkema wrote:

Hi,

Yesterday I noticed something strange happenign one on of our servers. Calls were being sent to servers within our VoIP platform by OpenSER without (as far as I can see) really being handled according to our OpenSER configuration.

When I looked into it, I found that the Request-URI contained the IP address of the internal server, instead of the IP address of our OpenSER machine or our SIP domain.

Maybe someone sent a SIP message with the local IP address in the R-URI to your proxy. According to your config this should not matter as you rewrite the domain for every incoming SIP request - except for loose-route.

For loose-route I would suggest to check for a to-tag too. Then, the called SIP UA should reject the call. You could also use dialog module to see if a dialog exists before forwarding in loose_route.

regards klaus

How can I check that the Request-URI contains only the SIP domain or the IP address of the OpenSER server?

Might this have something to do with the loose_route() block?

Here's (heavily edited) basically our INVITE handling code from openser.cfg:

if (loose_route()) { use_media_proxy();

t_relay(); exit; };

if (method=="INVITE") { t_on_reply("1");

rewritehost("SIP_DOMAIN");

# Check if it is international number format if (uri=~"^sip:00") { strip(2); };

if ( (method == "INVITE") ) { if (!proxy_authorize("SIP_DOMAIN", "subscriber")) { proxy_challenge("SIP_DOMAIN", "0"); exit; };

# let's check from=id ... avoids accounting confusion
if (!check_from())
{
	sl_send_reply("403", "That is ugly -- use

From=id next time (gw)"); exit; }; };

if (is_uri_host_local()) { log("ATS: incoming message is for a local host ($tu)");

route(3);

};