Subject: [Tsvwg] SHUTDOWN COMPLETE chunk bundled with DATA chunk

From: "Andrey Konstantinov" <[email-masked]>
Date: Fri, 25 May 2007 11:53:23 +0400

Hi,

I have a question, because I can not find the answer in RFC 2960.

There is a situation when SCTP receives packet with two chunks. First chunk
is SHUTDOWN COMPLETE, second chunk is DATA.
I know that packet is formed wrongly by remote side, but what is exact
behaviour on this packet?

I expect two variants:
1. SCTP stops processing of the message after SHUTDOWN COMPLETE chunk.
2. SCTP sends ABORT chunk on DATA chunk since the SHUTDOWN COMPLETE
chunk has been processed and there is no association for the DATA chunk.

Could you say me what solution is correct?

Best regards,
Andrey Konstantinov

---

From: devayya <[email-masked]>
Date: Fri, 25 May 2007 13:37:39 +0530

Andrey,

Since the SHUTDOWN COMPLETE is first chunk in the packet then the 
association state will reach CLOSED state. and so

The RFC 2960 says,

"A DATA chunk received in CLOSED is out of the blue and SHOULD be 
handled per 8.4."

Regards,
devayya

Andrey Konstantinov wrote:

> There is a situation when SCTP receives packet with two chunks. First 
> chunk is SHUTDOWN COMPLETE, second chunk is DATA.

---

From: Michael Tuexen <[email-masked]>
Date: Fri, 25 May 2007 10:56:12 +0200

Hi,

this is an error case where the packet violates many rules... This is  
even a conformance
test of the ETSI test suite:

TPId: SCTP_BDC_I_7_3

Status: Mandatory

Precondition: Association is established between tester and SUT is in  
SHUTDOWN-ACK sent state. Arrange
the data at the tester such that DATA chunks are multiplexed with  
SHUTDOWN COMPLETE
chunk with SHUTDOWN-COMPLETE as the first chunk.

Ref: RFC 2960 [1], section 6.10.

Purpose: Ensure that the IUT on receipt of any DATA chunks bundled  
with SHUTDOWN-COMPLETE
chunk discards this packet and remains in SHUTDOWN-ACK sent state or  
sends an ABORT
or accepts the SHUTDOWN-COMPLETE but ignores the DATA chunks.

Best regards
Michael

On May 25, 2007, at 10:07 AM, devayya wrote:

>>  There is a situation when SCTP receives packet with two chunks.  
>> First chunk is SHUTDOWN COMPLETE, second chunk is DATA.
>> I know that packet is formed wrongly by remote side, but what is  
>> exact behaviour on this packet?
>>  I expect two variants:
>> 2. SCTP sends ABORT chunk on DATA chunk since the SHUTDOWN  
>> COMPLETE chunk has been processed and there is no association for  
>> the DATA chunk.