Bug#500512: Wrong "via" header IP address

[Casper Langemeijer]

Hi All,

I try to connect from my home through a VPN connection to an asterisk
server. VPN and office network addresses are 172.24.x.x. My local
network is 192.168.1.x

linphone is advertising 192.168.1.22 (my local network IP) as host in
the "via" header.

I can see my asterisk server contacting 192.168.1.22 in my office
firewall error log. Apparently it receives the REGISTER packet and
responds to the IP in the "via" header.

Originally the sender address of the packets was my local network IP as
well. According to bugreport
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=500512#25 a possible
solution was to add an explicit route to my asterisk server, so I did.

$ route add 172.24.1.8 ppp0

It fixed that part of the problem. This seems to be the same issue as
mentioned in this debian bugreport.

Here is one of the REGISTER packets sent, copied from the Linphone debug
window:

message: cb_sndreq_retransmission (id=4)
message: eXosip: timer sec:4 usec:10000!
message: DNS resolution with 172.24.1.8:5060
message: getaddrinfo returned the following addresses:
message: 172.24.1.8 port 5060
message: Message sent: (to dest=172.24.1.8:5060)
REGISTER sip:172.24.1.8 SIP/2.0
Via: SIP/2.0/UDP 192.168.1.22:5060;rport;branch=z9hG4bK898566468
From: <sip:prdgfksj40 at 172.24.1.8>;tag=1790236968
To: <sip:prdgfksj40 at 172.24.1.8>
Call-ID: 952225778
CSeq: 4 REGISTER
Contact: <sip:prdgfksj40 at 172.24.4.3>
Max-Forwards: 70
User-Agent: Linphone/3.3.2 (eXosip2/3.3.0)
Expires: 600
Content-Length: 0

If I can help you by providing any other information, please let me
know.

Thank you,

Casper