[SR-Users] Unknown caller gets online user's identity

[g.aloitus at gmail.com]

Hello,

I'm using Kamailio version 4.1.4+precise (amd64).

I have followed "Kamailio 4.0.x and Asterisk 11.3.0 Realtime Integration 
using Asterisk Database" 
(http://kb.asipto.com/asterisk:realtime:kamailio-4.0.x-asterisk-11.3.0-astdb). 
One main difference in my setup compared to that one is that I continued 
use of Kamailio's database.

The problem is as follows:

I decided to put Kamailio and through it Asterisk reachable from 
internet. I have tried to configure Asterisk so that only calls of 
registered users would be possible, and they could only call to other 
registered users or conference rooms and echo test number.

Then I took the following steps:

I ensured that there was no online users with kamctl online. Then I 
launched MicroSIP (www.microsip.org), but I did not defined account, I 
simply set the protocol to tls and media encryption to mandatory, 
because I'm using these.

I called to extension with xxx at my.public.ip.address (where xxx is 
extension) getting "unauthorized". And that was what I wanted.

But if there is online users, calls go through, and incoming call is 
coming from Asterisk (in syslog I can find out that src_user=asterisk).

Kamailio and Asterisk are listening the same IP address, but different 
port. I have refused connections to the Asterisk's port with iptables.

I have defined my public IP address as domain in sip.conf. There is also 
other domain defined which corresponds to users' domain I am using in 
Kamailio's database.

In kamailio.cfg there is if statement which prevents Kamailio not to be 
open relay:

if (from_uri!=myself && uri!=myself)
...

If I change this for example:

if (from_uri!=myself || uri!=myself)

I get what I want this time: no calls from outside, but I somewhat think 
that this is not a final solution.

I have not found from log files such information which would have helped 
me. I have not yet investigated this problem so much that I could tell 
the logic behind the selection of online user's identity which is used. 
However, if I make a call to conference room I notice that Asterisk is 
thinking that one of online users has joined the conference.

If I can recall correctly, I started with Kamailio version 3.2, and 
integrated it with Asterisk 11 (currently 11.10.2). Is there something 
which has changed in Kamailio, but what I have not changed in my setup 
which could explain this.

Best,

Teijo