15 Sep
2019
15 Sep
'19
4:34 a.m.
I'm going to keep testing against the issue I originally reported, and
probably wait until after 5.3 is released. My issue may also be related to a
combination of TCPOPS keepalive not keeping the proper connection open for
UAC -> Kamailio/LCR -> TLS Gateway
The connection that's kept open to the TLS Gateway is the original forward of
the INVITE
<Kamailio IP>:<ephemeral port> -> <TLS Gateway>:<Port 5061>
The subsequent in-dialog connections (such as BYE from the UAC to the TLS
Gateway) don't use the original TLS connection so they are prevented from re-
connecting to the TLS Gateway.
Again, I have to do more testing to clear up the root issue on my end.
Also, for a more compact config, would the following achieve the same thing...
route[NATMANAGE] {
#!ifdef WITH_NAT
if(is_request()) {
if(has_totag()) {
if(check_route_param("nat=yes")) {
setbflag(FLB_NATB);
### Add the command here....
set_forward_no_connect();
}
}
}
...
On Wednesday, September 11, 2019 1:21:34 AM CDT Daniel-Constantin Mierla
wrote:
It no longer looks like an issue related to
set_reply_no_connect() or
set_forward_no_connect() added by the commit you referenced. Those were
added to prevent attempting to connect to devices behind the nat (in
that case the device has to maintain the connection, otherwise nobody
can connect back to it) as well as prevent someone in the wild sending a
request then closing the connection, without waiting for the reply,
which is typically routed back to via, commonly with an ephemeral port.
The follow up commit I did it in master recently is no longer setting
the flag for requests within dialog, but I understand you have
connection problems for requests within dialog, am I right?
Cheers,
Daniel
On 10.09.19 01:08, Anthony Joseph Messina wrote:
> I still ran into some trouble when one side was NAT'd.
>
> Am I correct in thinking that it would be undesirable to maintain a
> TCP/TLS
> connection to an upstream TLS gateway that is using the well-known port
> 5061?
>
> I was thinking this may be a case for TCP_REUSEPORT and force_send_socket,
> but that seems a little complex seeing as I can just let Kamailio
> reconnect (when necessary) rather than preventing the outbound TLS from
> connecting when it would otherwise succeed.
>
> I'll try and work through more detailed configuration scenarios. -A
>
> On Monday, September 9, 2019 2:12:07 AM CDT Daniel-Constantin Mierla
wrote:
>> Hello,
>>
>> I relaxed that condition to not connect on forwarding only for initial
>> requests going though nat. Can you test with latest master and see how
>> is going for your use case?
>>
>> Cheers,
>> Daniel
>>
>> On 09.09.19 02:00, Anthony Joseph Messina wrote:
>>> In preparation for the 5.3 release, I've been testing the following
>>> configuration change for TCP/TLS connections:
>>>
>>> https://github.com/kamailio/kamailio/commit/
>>> 8bba208fe6ae7ccb4c92362b8c33f1530b9f56da
>>>
>>> route[REQINIT] {
>>>
>>> # no connect for sending replies
>>> set_reply_no_connect();
>>> if(has_totag()) {
>>>
>>> # no connect for requests within dialog
>>> set_forward_no_connect();
>>>
>>> }
>>>
>>> This change creates issues when a UAC TLS INVITE routes to an upstream
>>> gateway using TLS to port 5061 (via the LCR module). Kamailio sends the
>>> initial outbound TLS connection from a local ephemeral port. The TCPOPS
>>> tcp_keepalive_enable function issues keepalives from the local ephemeral
>>> port to the gateway port 5061:
>>>
>>> https://kamailio.org/docs/modules/stable/modules/
>>> tcpops#tcpops.f.tcp_keepalive_enable
>>>
>>> Even so, the TLS connection eventually times out, after which in-dialog
>>> requests from the UAC are no longer able to reach the upstream gateway.
>>>
>>> ERROR: tm [../../core/forward.h:293]: msg_send_buffer(): tcp_send failed
>>> WARNING: tm [t_fwd.c:1570]: t_send_branch(): sending request on branch 0
>>> failed
>>> ERROR: sl [sl_funcs.c:372]: sl_reply_error(): stateless error reply
>>> used:
>>> Unfortunately error on sending to next hop occurred (477/SL)
>>>
>>> I figure I must be doing something wrong with my TCPOPS here. Is a TLS
>>> connection to an upstream gateway supposed to be maintained throughout
>>> the
>>> duration of a call?