#384 B2B and CANCEL transaction

[Denis]

Hello!
There are two proxies of version 1.6.4.-2 which has been installed on the same server.
One proxy (proxy1) using B2B “top hiding” and located in /usr/local/sbc and using one signaling port
Another proxy (proxy2) is just SIP proxy and located in /usr/local/opensips1.6.4/ and using another signaling port
Both proxies using the same ip address of the server
Call flow:
some UA – proxy1 – proxy2 – some gateway
When UA generate CANCEL then proxy1 does some strange things with FROM or TO uri headers (you can see it in attachment). Because of this proxy2 cannot parse CANCEL properly and transaction in proxy2 cannot be canceled.
I found that this problem appears when I use append_hf() to add some header in local route of the proxy1 before sending INVITE to proxy2. Without this adding problem disappears.

[Denis]

cancel debug

[Anca Vamanu]

Hi Bogdan,

This bug fix requires further work in tm module, in local_route processing, so as to update the shortcuts in tm when lumps are applied for headers also. The fix that was committed last week solved this problem only when body lumps were applied.
Unfortunately, I don't have time to work on this, so I have removed the assignation to me for this bug report.

Regards,
Anca

[Ryan Bullock]

I am having the same issue. If I apply any changes to an Invite generated from the b2bua and then a CANCEL is sent from ua, the opensips b2bua ends up doing odd things to the CANCEL requests that it generates.

When not applying changes to the Invite the subsequent CANCEL will be properly formatted, although it does not appear to respect the User-Agent string set in the configuration.

[Logan]

I'm seeing the same thing.

Reference:

192.168.1.146 = Opensips Proxy
192.168.1.145 = Opensips B2BUA
10.2.3.245 = Carrier

U 2011/12/01 22:51:11.558887 192.168.1.146:5060 -> 192.168.1.145:5090
CANCEL sip:9993512125551212@192.168.1.145:5090 SIP/2.0.
Via: SIP/2.0/UDP 192.168.1.146;branch=z9hG4bK2df7.78db1d81.0.
From: "James Logan" <sip:8884442222@192.168.1.137>;tag=as06eabdcd.
Call-ID: 40c30c6459b3eaa4683991082381cadb@192.168.1.137.
To: "12125551212" <sip:12125551212@192.168.1.146>.
CSeq: 102 CANCEL.
Max-Forwards: 70.
User-Agent: Opensips.
Content-Length: 0.
.

U 2011/12/01 22:51:11.559378 192.168.1.145:5090 -> 192.168.1.146:5060
SIP/2.0 200 canceling.
Via: SIP/2.0/UDP 192.168.1.146;branch=z9hG4bK2df7.78db1d81.0.
From: "James Logan" <sip:8884442222@192.168.1.137>;tag=as06eabdcd.
Call-ID: 40c30c6459b3eaa4683991082381cadb@192.168.1.137.
To: "12125551212" <sip:12125551212@192.168.1.146>;tag=3330ae74b9cf9aed85afbc9203dd6238-715f
CSeq: 102 CANCEL.
Server: B2BUA.
Content-Length: 0.
.

U 2011/12/01 22:51:11.559527 192.168.1.145:5090 -> 10.2.3.245:5060
CANCEL ............i...............i.. SIP/2.0.
Via: SIP/2.0/UDP 192.168.1.145:5090;branch=z9hG4bK5421.22999dd2.0.
........B2B.256.3572553sip:+12125551212@10.2.3.245sip:8884442222@192.168.1.1379120d3`.....p..i...........................................q.i............
........ CANCEL.
User-Agent: OpenSIPS (1.7.1-notls (x86_64/linux)).
Max-Forwards: 70.
User-Agent: Opensips.
Init-CallID: 40c30c6459b3eaa4683991082381cadb@192.168.1.137.
Contact: <sip:192.168.1.145:5090>.

[a719719]

This bug is also present in version 1.7.2.

It can be reproduced with this configuration file: http://pastebin.freeswitch.org/18579
192.168.178.2 = softphone
192.168.178.28 = OpenSIPS 1.7.2
192.168.178.29 = Asterisk

There are two problems:

1. Mangled ACK: http://pastebin.freeswitch.org/18580
This problem occurs every 5-15 calls. I have no idea what is triggering it and why it doesn't happen every call.

2. Mangled CANCEL and default User-Agent header in the CANCEL: http://pastebin.freeswitch.org/18581
Only in the CANCEL request the default User-Agent header is present. This happens every call.
The mangled CANCEL message is quite rare and i have no idea what is triggering it.

[a719719]

The user-agent issue is unrelated to the mangeling of messages. Fix for that was: http://opensips.svn.sourceforge.net/viewvc/opensips?view=revision&sortby=date&revision=8766

The fix for the mangeling of messages is related to http://opensips.svn.sourceforge.net/viewvc/opensips?view=revision&sortby=date&revision=8003 if i understand the comment of anca_vamanu correct but i am not able to write the patch.

Question to the other reporters of this problem; did you find a workarround to use append_hf() with B2B?

[Bogdan-Andrei Iancu]

Investigating possible fixes

[Bogdan-Andrei Iancu]

Hi all,

This was fixed in trunk / 1.8.0 - backport is a bit hard to do , so better consider upgrading to 1.8.0

Regards,
Bogdan