From: owner-atnp_sgb2@cena.fr on behalf of Tony Kerr
[tony.kerr@cival.co.uk]
Sent: 14 October 2002 14:34
To: atnp_ccb_chair@tls.cena.fr
Cc: atnp_sgb2@tls.cena.fr; atnp_ccb_sme4@tls.cena.fr;
atnp_sgb3@tls.cena.fr
Subject: PDR M2080002 - ULCS - SE-Transfer End Flag - RESOLVED

Title: 			ULCS - SE-Transfer End Flag

PDR Reference:          	M2080002

Originator Reference:

SARPs Document Reference:   	Ed 3 Sub-Volume IV, section 4.8.5 (SA-CF)

CAMAL Document Reference:	Draft ed 2, Part IV, section 2.15

P/OICS Document Reference	-

Status:                     	RESOLVED

Impact:					B

PDR Revision Date:              	04 Oct 2002 (Proposed -> Resolved)
						23 Sep 2002 (Accepted -> Proposed)
						05 Sep 2002 (Submitted -> Accepted)
						13 Aug 2002 (Submitted)

Submitting State/Organization:    	CIVAL Consulting Ltd

Submitting Author Name:          	A J Kerr

Submitting Author E-mail Address:  	tony.kerr@cival.co.uk

Submitting Author Supplemental Contact Information: Tel: +44 (0)1252 724386

SARPs Date:                      	Doc 9705 Ed 3 (Jul 02)

P/OICS Date:				-

SARPs Language:                  	English

Summary of Defect:

According to the Security Exchange Protocol Machine (SEPM) defined in
normative Annex A of the SESE protocol specification (ISO/IEC 11586-3 |
ITU-T Rec. X.832), the End Flag of the SE-Transfer service is used to
control SEPM state transitions.  In the ATN Security ASO specification, the
End Flag is "not used" in all invocations of SE-TRANSFER.  The effect of
this is that the flag takes its default value of FALSE and SEPM gets stuck
in STA1 Exchange State as soon as the first SE-Transfer req is issued or
SETR APDU is received.  This in turn could lead to SESE implementations
detecting false sequence errors in security exchanges, and also affects the
handling of SE-U-Abort req and SEAB APDU input events, which are only valid
in STA1.

According to the SESE service definition (ISO/IEC 11586-2 | ITU-T Rec.
X.831), the End Flag is "U" (User option) in SE-Transfer req and "C(=)" in
SE-Transfer ind.  However, endFlag is NOT optional in the ASN.1 definition
of the SETransfer APDU; it is DEFAULT FALSE.  Support for the end flag is
mandatory in the PICS.


Assigned SME:                    	Sub-Volume IV SME

Proposed SARPs amendment:

In Table 4.8-7, change End flag from "not used" to "False"
In Table 4.8-13, change End flag from "not used" to "True"
In Table 4.8-17, change End flag from "not used" to "True"

Proposed CAMAL (ed 2) amendment:

In Table IV-2-29, change End flag from "Not used" to "False"
In Table IV-2-32, change End flag from "Not used" to "False"
In Table IV-2-40, change End flag from "absent" to "True"
In Table IV-2-43, change End flag from "absent" to "True"
In Table IV-2-58, change End flag from "Not used" to "False"
In Table IV-2-61, change End flag from "Not used" to "False"
In Table IV-2-68, change End flag from "absent" to "True"
In Table IV-2-71, change End flag from "absent" to "True"
In Table IV-2-78, change End flag from "absent" to "True"
In Table IV-2-81, change End flag from "absent" to "True"
In Table IV-2-88, change End flag from "absent" to "True"
In Table IV-2-91, change End flag from "absent" to "True"
In Table IV-2-98, change End flag from "absent" to "True"
In Table IV-2-99, change End flag from "absent" to "True"
In Table IV-2-106, change End flag from "absent" to "True"
In Table IV-2-109, change End flag from "absent" to "True"
In Table IV-2-116, change End flag from "absent" to "True"
In Table IV-2-119, change End flag from "absent" to "True"

In 2.15.6.2:
REPLACE "endFlag = FALSE (default value)" with "endFlag = TRUE"
REPLACE "2X ('X' is the binary string '001'B)" WITH "23"
REPLACE
01 0	Bitmap: invocationId absent (default
	noInvocationId, startFlag present, endFlag
	absent (default FALSE)
WITH
01 1	Bitmap: invocationId absent (default
	noInvocationId, startFlag present, endFlag
	present

AFTER "1	(u)startFlag(/u) BOOLEAN = TRUE"
APPEND "1	(u)endFlag(/u)	BOOLEAN = TRUE"
((u) indicates underline)

In 2.15.6.3:
REPLACE "endFlag = FALSE (default value)" with "endFlag = TRUE"
REPLACE "0X ('X' is the binary string '00'B)"
WITH  "0X ('X' is the binary string '001'B)"

REPLACE
00 0	Bitmap: invocationId absent (default
	noInvocationId, startFlag absent (default
	FALSE), endFlag absent (default FALSE)
WITH
00 1	Bitmap: invocationId absent (default
	noInvocationId, startFlag absent (default
	FALSE), endFlag present

AFTER "0000 00	Padding to octet boundary for seItem"
APPEND "1	(u)endFlag(/u)	BOOLEAN = TRUE"
((u) indicates underline)


Impact on interoperability:

Without the amendment proposed in this PDR, endFlag will always have the
default FALSE value and hence be omitted from SETransfer APDUs.  With the
amendment, endFlag will be TRUE in all currently defined security exchanges
apart from the initial signed key management message.  This will add one
extra bit to the air-ground message in these cases.  SASO implementations
that exceed the SARPs requirements and rigorously check the value of the end
flag may fail when receiving a SETR with the flag unexpectedly set to TRUE.

PDR Validation Status:  Inspection should be sufficient.

SME Recommendation to CCB: 	Resolved

CCB Decision:       		Resolved (CCB/16, Toulouse, 04 Oct 2002)