New subject: Kamailio does not add port number to addresses in Via, Record-Route headers

11 Dec 2017

Hello all,

I have the following issue in my configuration, tested with 5.2.0-rc1 so
far:

At some point, I set the $fs pseudovariable to force a request to be
relayed through a specific socket. Although this is honoured by kamailio
(i.e. the request does indeed leave the kamailio host from the respective
socket), the port number is not added to the Via and RR headers. As a
result, all replies to the request, as well as all subsequent requests from
the other SIP UA are relayed to the default port, 5060. Here's an example:

SIP UAC to kamailio:
INVITE 192.168.1.1:5060 ---> 192.168.1.254:5060
Kamailio to UAS ($fs is set):
INVITE 2.2.2.2:5066 ---> 3.3.3.3:5060
Topmost Via in request relayed by kamailio is:
SIP/2.0/UDP 2.2.2.2;branch=aaaaaaaaaaaaaa    <- port 5066 is not added
Topmost RR in request relayed by kamailio is:
<sip:2.2.2.2;r2=on;lr;did=bbbbbbb;nat=yes>    <- port 5066 is not added
RESULT: Reply from UAS is sent to 2.2.2.2:5060

Is this behaviour valid? Am I missing anything? Kamailio is configured to
listen on both sockets on IP 2.2.2.2, namely: a) udp:2.2.2.2:5060 and b)
2.2.2.2:5066. Thanks.

BR,
George