6 Aug
2015
6 Aug
'15
10:21 p.m.
First, a spec reference: https://tools.ietf.org/html/rfc3261#section-10.2.4
A UA SHOULD use the same Call-ID for all registrations
during a single boot cycle.
On the surface is is then reasonable for Kamailio to default to contact lookup by contact
and Call-ID. It does, however, [default to contact only
lookup](http://kamailio.org/docs/modules/4.2.x/modules/usrloc.html#usrloc.p….
In a repeat registration scenario like this:
~15:32:28
```
REGISTER sip:ben-test.callix.com.br SIP/2.0
Call-ID: aa26998a7a2648a6243a11eda51a3aa6(a)172.31.31.221
CSeq: 2 REGISTER
From:
<sip:destination_007@ben-test.callix.com.br>;tag=61616278_117e27da_7c77d0dd_13a609f6-c985-463b-b43f-ac43090d221e
To: <sip:destination_007@ben-test.callix.com.br>
Max-Forwards: 70
Contact: <sip:destination_007@172.31.31.221:5080>
User-Agent: Callix/Click2Call
Expires: 180
Via: SIP/2.0/UDP
chandler.localdomain:5080;branch=z9hG4bK13a609f6-c985-463b-b43f-ac43090d221e_7c77d0dd_e6dd0acb-255f-4c1c-afe6-67a360a7f581
Authorization: Digest
username="destination_007",realm="ben-test.callix.com.br",nonce="VcItt1XCLIsaLIdqq1Uo9wYmRIbpfQhP",uri="sip:ben-test.callix.com.br",response="0a014dd4613deb4b89fc9457d43d5cee"
Route: <sip:registrar.oneclick.callix.com.br;lr>
Content-Length: 0
SIP/2.0 200 OK
Call-ID: aa26998a7a2648a6243a11eda51a3aa6(a)172.31.31.221
CSeq: 2 REGISTER
From:
<sip:destination_007@ben-test.callix.com.br>;tag=61616278_117e27da_7c77d0dd_13a609f6-c985-463b-b43f-ac43090d221e
To:
<sip:destination_007@ben-test.callix.com.br>;tag=b27e1a1d33761e85846fc98f5f3a7e58.73ee
Via: SIP/2.0/UDP
chandler.localdomain:5080;branch=z9hG4bK13a609f6-c985-463b-b43f-ac43090d221e_7c77d0dd_e6dd0acb-255f-4c1c-afe6-67a360a7f581;received=172.31.31.221
Contact: <sip:destination_007@172.31.31.221:5080>;expires=180
Supported: outbound
Server: kamailio (4.1.6 (x86_64/linux))
Content-Length: 0
```
~15:34:28
```
REGISTER sip:ben-test.callix.com.br SIP/2.0
Call-ID: d6a13584901f0336dd9f877f125f1574(a)172.31.31.221
CSeq: 2 REGISTER
From:
<sip:destination_007@ben-test.callix.com.br>;tag=10060555_117e27da_7c77d0dd_13a609f6-c985-463b-b43f-ac43090d221e
To: <sip:destination_007@ben-test.callix.com.br>
Max-Forwards: 70
Contact: <sip:destination_007@172.31.31.221:5080>
User-Agent: Callix/Click2Call
Expires: 180
Via: SIP/2.0/UDP
chandler.localdomain:5080;branch=z9hG4bK13a609f6-c985-463b-b43f-ac43090d221e_7c77d0dd_4c667124-f13e-4bae-b637-4f19472bd417
Authorization: Digest
username="destination_007",realm="ben-test.callix.com.br",nonce="VcIuMFXCLQQbB0Z4Q92WkVEu4iM2wjU3",uri="sip:ben-test.callix.com.br",response="8161b70052e50a5e3f51a843080c1eac"
Route: <sip:registrar.oneclick.callix.com.br;lr>
Content-Length: 0
SIP/2.0 200 OK
Call-ID: d6a13584901f0336dd9f877f125f1574(a)172.31.31.221
CSeq: 2 REGISTER
From:
<sip:destination_007@ben-test.callix.com.br>;tag=10060555_117e27da_7c77d0dd_13a609f6-c985-463b-b43f-ac43090d221e
To:
<sip:destination_007@ben-test.callix.com.br>;tag=b27e1a1d33761e85846fc98f5f3a7e58.6229
Via: SIP/2.0/UDP
chandler.localdomain:5080;branch=z9hG4bK13a609f6-c985-463b-b43f-ac43090d221e_7c77d0dd_4c667124-f13e-4bae-b637-4f19472bd417;received=172.31.31.221
Contact: <sip:destination_007@172.31.31.221:5080>;expires=180
Supported: outbound
Server: kamailio (4.1.6 (x86_64/linux))
Content-Length: 0
```
I see the following queries in the Kamailio logs:
```
Aug 5 15:32:28 lexington /usr/sbin/kamailio[12366]: DEBUG: db_postgres [km_dbase.c:230]:
db_postgres_submit_query(): sending query ok: 0x7fc5155669a0 (1) - [insert into location
(username,contact,expires,q,callid,cseq,flags,cflags,user_agent,received,path,socket,methods,last_modified,ruid,instance,reg_id,domain
) values
('destination_007','sip:destination_007@172.31.31.221:5080','2015-08-05
15:35:28',-1.00
,'aa26998a7a2648a6243a11eda51a3aa6@172.31.31.221',2,0,0,'Callix/Click2Call',NULL,NULL,'udp:172.31.26.82:5060',NULL,'2015-08-05
15:32:28','uloc-55c220c7-304e-96',NULL,0,'ben-test.callix.com.br')]
Aug 5 15:34:28 lexington /usr/sbin/kamailio[12364]: DEBUG: db_postgres [km_dbase.c:230]:
db_postgres_submit_query(): sending query ok: 0x7fc5155669a0 (2) - [select
contact,expires,q,callid,cseq,flags,cflags,user_agent,received,path,socket,methods,last_modified,ruid,instance,reg_id
from location where username='destination_007' AND
domain='ben-test.callix.com.br' order by q]
Aug 5 15:34:28 lexington /usr/sbin/kamailio[12364]: DEBUG: db_postgres [km_dbase.c:230]:
db_postgres_submit_query(): sending query ok: 0x7fc5155669a0 (1) - [update location set
expires='2015-08-05 15:37:28',q=-1.00
,cseq=2,flags=0,cflags=0,user_agent='Callix/Click2Call',received=NULL,path=NULL,socket='udp:172.31.26.82:5060',methods=NULL,last_modified='2015-08-05
15:34:28',ruid='uloc-55c220c7-304e-96',instance=NULL,reg_id=0,contact='sip:destination_007@172.31.31.221:5080'
where username='destination_007' AND
contact='sip:destination_007@172.31.31.221:5080' AND
callid='d6a13584901f0336dd9f877f125f1574(a)172.31.31.221' AND
domain='ben-test.callix.com.br']
```
Evidently the contact-only nature of usrloc lookup is not being respected when a follow-up
registration is attempted. This means that every pre-expiry registration for a static
contact from a UA which does not comply with RFC3621's normative `SHOULD` will
silently fail. This is not a big deal; most do comply and I could fix mine to comply.
What is a bigger deal is that if the UA is restarted, it is not to be reasonably expected
to maintain the same CallID. It will use a new CallID (precisely the same way as my
"faulty" UA does) on its first registration. If this occurs while there is an
active registration for the same Contact, this new registration will effectively be
ignored.
I *think*, though I'm likely to be corrected, that we should only be including the
CallID in the UPDATE's WHERE clause if we used it in the SELECT and got a result. In
my "faulty" UA case, this would at least leave me with duplicate registrations
rather than 0 registrations. I could then follow the normative `SHOULD` and eliminate the
duplication.
Caveat that I have only tested with usrloc's `dbmode` parameter as `3`. I am using
Postgres.
---
Reply to this email directly or view it on GitHub:
https://github.com/kamailio/kamailio/issues/280