[sr-dev] notify cseq is not incremented

[Juha Heinanen]

while doing some presence tests with master i noticed that when presence
server sends notify that terminates subscription due to change in xcap
authorization rules, cseq in the notify is same as in previous one.

rfc3261 says in 12.2.1 UAC Behavior:

   Requests within a dialog MUST contain strictly monotonically
   increasing and contiguous CSeq sequence numbers (increasing-by-one)
   in each direction (excepting ACK and CANCEL of course, whose numbers
   equal the requests being acknowledged or cancelled).

so this looks like a bug to twinkle (and me).  below is sip debug from
twinkle (subscriber).

-- juha

+++ 2-5-2012 08:50:41.158705 INFO SIP ::process_sip_msg
Received from: tcp:192.98.103.10:5060
NOTIFY sip:jh at 192.98.103.10:5074;transport=tcp SIP/2.0
Via: SIP/2.0/TCP 192.98.103.10;branch=z9hG4bK4da2.6447f6ae08e84f0c0fbec6f7090757cc.0;i=c1
Via: SIP/2.0/TCP 127.0.0.1:5082;branch=z9hG4bK4da2.4e788af3000000000000000000000000.0
To: sip:jh at test.fi;tag=pqazy
From: sip:test at test.fi;tag=4a664ec84c547b2d0bc0fe8965f834e4-8a4b
CSeq: 2 NOTIFY
Call-ID: byxobtomskpzmos at siika.tutpro.com
Content-Length: 210
User-Agent: OpenXg Presence/XCAP Server  (3.3.0-dev8 (x86_64/linux))
Max-Forwards: 69
Event: presence
Contact: <sip:127.0.0.1:5082;alias=127.0.0.1~35306~2;transport=tcp>
Subscription-State: active;expires=3670
Content-Type: application/pidf+xml

<?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" entity="sip:test at test.fi">
  <tuple id="gxsdoz">
    <status>
      <basic>open</basic>
    </status>
  </tuple>
</presence>

---

+++ 2-5-2012 08:50:41.161169 INFO SIP ::send_sip_tcp
Send to: tcp:192.98.103.10:5060
SIP/2.0 200 OK
Via: SIP/2.0/TCP 192.98.103.10;branch=z9hG4bK4da2.6447f6ae08e84f0c0fbec6f7090757cc.0;i=c1,SIP/2.0/TCP 127.0.0.1:5082;branch=z9hG4bK4da2.4e788af3000000000000000000000000.0
To: <sip:jh at test.fi>;tag=pqazy
From: <sip:test at test.fi>;tag=4a664ec84c547b2d0bc0fe8965f834e4-8a4b
Call-ID: byxobtomskpzmos at siika.tutpro.com
CSeq: 2 NOTIFY
Server: Twinkle/1.4.2
Content-Length: 0


---

+++ 2-5-2012 08:51:00.381465 INFO SIP ::process_sip_msg
Received from: tcp:192.98.103.10:5060
NOTIFY sip:jh at 192.98.103.10:5074;transport=tcp SIP/2.0
Via: SIP/2.0/TCP 192.98.103.10;branch=z9hG4bK4da2.fd70b43b9da3c3b488208a61595b1112.0;i=c1
Via: SIP/2.0/TCP 127.0.0.1:5082;branch=z9hG4bK4da2.444a74e2000000000000000000000000.0
To: sip:jh at test.fi;tag=pqazy
From: sip:test at test.fi;tag=4a664ec84c547b2d0bc0fe8965f834e4-8a4b
CSeq: 2 NOTIFY
Call-ID: byxobtomskpzmos at siika.tutpro.com
Content-Length: 0
User-Agent: OpenXg Presence/XCAP Server  (3.3.0-dev8 (x86_64/linux))
Max-Forwards: 69
Event: presence
Contact: <sip:127.0.0.1:5082;alias=127.0.0.1~35306~2;transport=tcp>
Subscription-State: terminated;reason=terminated

---

+++ 2-5-2012 08:51:00.381794 WARNING NORMAL t_subscription_dialog::recvd_request
CSeq seqnr is out of sequence.
Reveived seqnr: 2
Remote seqnr: 2