5 Apr
2017
5 Apr
'17
4:35 p.m.
On Wed, Apr 05, 2017 at 02:25:29PM +0200, Abdoul Osséni wrote:
The advantage of the SIP ping options is a
bidirectional traffic through
NAT. I think in this case, my issue will be solved.
Due to some limitations of the nat helper pinger (3 backends, one should
ping at hh:mm:00, the other at hh:mm:20 and last at hh:mm:40) I decided
to run my own external pinger process that sends OPTIONS to all
registered users via kamailio (in my case via a loadbalancer based on
path headers). Based on the $fU and source ip these requests are forwarded to the
endpoints (in my example from path received header, in your case that may be just received
(and transport for the tcp/tls clients) in contact).
kamailio.cfg option forwarding:
if(is_method("OPTIONS") && $fU=="pinger" &&
is_in_subnet($si, "127.0.0.0/8")) {
record_route();
remove_hf("Route");
$avp(route)=$(hdr(Route)[0]);
$avp(route)=$(avp(route){s.strip,1});
$avp(route)=$(avp(route){s.striptail,1});
$avp(received)=$(avp(route){uri.param,received});
$avp(received)=$(avp(received){s.unescape.param});
$du=$avp(received);
route(RELAY);
exit;
}
The options are generated with a php script:
if($res=mysql_query("select * from location order by rand()"))
{
while($row=mysql_fetch_assoc($res))
{
usleep(1000);
$branch=uniqid();
$dst=preg_replace('/.*(a)([^;]+);.*/',"$1",$row['path'])uot;,$row['path']);
$dst=explode(':',$dst);
if(count($dst)<2)
{
$dst[1]=5060;
}
$str=<<<EOS
OPTIONS {$row['contact']} SIP/2.0\r
Via: SIP/2.0/UDP 127.0.1.1:$listenport;branch=$branch;rport;alias\r
Route: {$row['path']}\r
From: sip:pinger@my.doma.in;tag={$row['ruid']}\r
To: {$row['contact']}\r
Call-ID: {$row['id']}-$listenport-$uid@localhost\r
CSeq: 1 OPTIONS\r
Content-Length: 0\r
\r
EOS;
socket_sendto($sock,$str,strlen($str),MSG_EOR,$dst[0],$dst[1]);
}
}