ISO/IEC 9594-11:2020

Information technology — Open systems interconnection directory — Part 11: Protocol specifications for secure operations

The scope of this Recommendation | International Standard is threefold. This Recommendation | International Standard provides guidance on how to prepare new and old protocols for cryptographic algorithm migration, and defines auxiliary cryptographic algorithms to be used for migration purposes. This Recommendation | International Standard specifies a general wrapper protocol that provides authentication, integrity and confidentiality (encryption) protection for other protocols. This wrapper protocol includes a migration path for cryptographic algorithms allowing for smooth migration to stronger cryptographic algorithms as such requirements evolve. This will allow migration to quantum-safe cryptographic algorithms. Protected protocols can then be developed without taking security and cryptographic algorithms into consideration. This Recommendation | International Standard also includes some protocols to be protected by the wrapper protocol primarily for support of public-key infrastructure (PKI). Other specifications, e.g., Recommendations or International Standards, may also develop protocols designed to be protected by the wrapper protocol.

Technologies de l'information — Interconnexion de systèmes ouverts (OSI) — Partie 11: Titre manque

General Information

• Status: Published
• Publication Date: 21-Dec-2020
• ICS: 35.100.70 - Application layer
• Technical Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Drafting Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Current Stage: 6060 - International Standard published
• Start Date: 22-Dec-2020
• Due Date: 25-Oct-2020
• Completion Date: 22-Dec-2020

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 9594-11
First edition
2020-12
Information technology — Open
systems interconnection directory —
Part 11:
Protocol specifications for secure
operations
Reference number
ISO/IEC 9594-11:2020(E)
©
ISO/IEC 2020

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ISO/IEC 9594-11:2020(E)

COPYRIGHT PROTECTED DOCUMENT
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ISO/IEC 9594-11:2020(E)

INTERNATIONAL STANDARD ISO/IEC 9594-11
RECOMMENDATION ITU-T X.510
Information technology – Open Systems Interconnection –
The Directory: Protocol specifications for secure operations



Summary
Recommendation ITU-T X.510 | ISO/IEC 9594-11 specifies a general protocol, called the wrapper protocol, that provides
cybersecurity for protocols designed for its protection. The wrapper protocol provides authentication, integrity and
optionally confidentiality (encryption). The wrapper protocol allows cybersecurity to be provided independently of the
protected protocols, which means that security may be enhanced without affecting protected protocol specifications.
The wrapper protocol is specified without specifying specific cryptographic algorithms, but is designed for plucking-in
cryptographic algorithms as required.
The wrapper protocol is designed for easy migration of cryptographic algorithms, as stronger cryptographic algorithms
become necessary.
Recommendation ITU-T X.510 | ISO/IEC 9594-11 contains recommendations for how other Recommendations and
International Standards may include features for migration of cryptographic algorithms, and it includes ASN.1
specifications to be applied for that purpose.
Recommendation ITU-T X.510 | ISO/IEC 9594-11 also specifies three protocols that make use of the wrapper protocol
protection. This includes a protocol for maintenance of authorization and validation lists (AVLs), a protocol for subscribing
of public-key certificate status and a protocol for accessing a trust broker.


History
*
Edition Recommendation Approval Study Group Unique ID
1.0 ITU-T X.510 2020-08-22 17 11.1002/1000/14320



Keywords
Certification authority, cryptography, cryptographic algorithm, digital signature, public-key certificate, PKI, quantum-safe,
trust anchor, validation.


*
To access the Recommendation, type the URL http://handle.itu.int/ in the address field of your web browser, followed by the
Recommendation's unique ID. For example, http://handle.itu.int/11.1002/1000/11830-en.
© ISO/IEC 2020 – All rights reserved
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ISO/IEC 9594-11:2020(E)

FOREWORD
The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of
telecommunications, information and communication technologies (ICTs). The ITU Telecommunication
Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical,
operating and tariff questions and issuing Recommendations on them with a view to standardizing
telecommunications on a worldwide basis.
The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes
the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics.
The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1.
In some areas of information technology which fall within ITU-T's purview, the necessary standards are
prepared on a collaborative basis with ISO and IEC.



NOTE
In this Recommendation, the expression "Administration" is used for conciseness to indicate both a
telecommunication administration and a recognized operating agency.
Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain
mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the
Recommendation is achieved when all of these mandatory provisions are met. The words "shall" or some other
obligatory language such as "must" and the negative equivalents are used to express requirements. The use of
such words does not suggest that compliance with the Recommendation is required of any party.




INTELLECTUAL PROPERTY RIGHTS
ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve
the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or
applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of
the Recommendation development process.
As of the date of approval of this Recommendation, ITU had received notice of intellectual property, protected
by patents, which may be required to implement this Recommendation. However, implementers are cautioned
that this may not represent the latest information and are therefore strongly urged to consult the TSB patent
database at http://www.itu.int/ITU-T/ipr/.



 ITU 2020
All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior
written permission of ITU.
© ISO/IEC 2020 – All rights reserved
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ISO/IEC 9594-11:2020(E)

CONTENTS
Page
SECTION 1 – GENERAL . 1
1 Scope . 1
2 Normative references . 1
2.1 Identical Recommendations | International Standards . 1
2.2 Other references . 1
3 Definitions . 2
3.1 OSI Reference Model definitions . 2
3.2 Directory model definitions . 2
3.3 Public-key and attribute certificate definitions . 2
3.4 Terms specified by this Recommendation | International Standard . 2
4 Abbreviations . 3
5 Conventions . 4
6 Common data types and special cryptographic algorithms . 4
6.1 Introduction . 4
6.2 ASN.1 information object class specification tool . 4
6.3 Multiple-cryptographic algorithm specifications . 6
6.4 Key establishment algorithms . 7
6.5 Multiple-cryptographic algorithm-value pairs . 9
6.6 Formal specification of encipherment . 11
7 General concepts for securing protocols. 11
7.1 Introduction . 11
7.2 Protected protocol plug-in concept. 12
7.3 Communications structure. 12
7.4 Another view of the relationship between the wrapper protocol and the protected protocol . 12
7.5 Structure of application protocol data unit . 13
7.6 Exception conditions . 13
SECTION 2 – THE WRAPPER PROTOCOL . 14
8 Wrapper protocol general concepts . 14
8.1 Introduction . 14
8.2 UTC time specification . 14
8.3 Use of alternative cryptographic algorithms . 14
8.4 General on establishing shared keys . 14
8.5 Sequence numbers . 15
8.6 Use of invocation identification in the wrapper protocol . 15
8.7 Mapping to underlying services . 15
8.8 Definition of protected protocols . 15
8.9 Overview of wrapper protocol data units . 15
9 Association management . 16
9.1 Introduction to association management . 16
9.2 Association handshake request . 16
9.3 Association accept . 18
9.4 Association reject due to security issues . 19
9.5 Association reject by the protected protocol . 20
9.6 Handshake security abort . 21
9.7 Handshake abort by protected protocol . 21
9.8 Data transfer security abort . 22
9.9 Abort by protected protocol . 22
9.10 Release request WrPDU . 23
9.11 Release response WrPDU . 23
9.12 Release collision. 24
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ISO/IEC 9594-11:2020(E)

Page
10 Data transfer phase . 24
10.1 Symmetric keys renewal . 24
10.2 Data transfer by the client . 24
10.3 Data transfer by the server . 26
11 Information flow . 28
11.1 Purpose and general model . 28
11.2 Protected protocol SAOC . 29
11.3 Wrapper SAOC . 29
12 Wrapper error handling . 32
12.1 General . 32
12.2 Checking of a wrapper handshake request . 32
12.3 Checking of a wrapper handshake accept . 33
12.4 Checking of data transfer WrPDUs . 34
12.5 Wrapper diagnostic codes . 36
SECTION 3 – PROTECTED PROTOCOLS . 37
13 Authorization and validation list management . 37
13.1 General on authorization and validation management . 37
13.2 Defined protected protocol data unit (PrPDU) types. 37
13.3 Authorization and validation management protocol initialization request . 38
13.4 Authorization and validation management protocol initialization accept9 . 38
13.5 Authorization and validation management protocol initialization reject . 38
13.6 Authorization and validation management protocol initialization abort . 38
13.7 Add authorization and validation list request . 39
13.8 Add authorization and validation list response . 40
13.9 Replace authorization and validation list request . 40
13.10 Replace authorization and validation list response. 40
13.11 Delete authorization and validation list request . 41
13.12 Delete authorization and validation list response . 41
13.13 Authorization and validation list abort . 42
13.14 Authorization and validation list error codes . 42
14 Certification authority subscription protocol . 43
14.1 Certification authority subscription introduction . 43
14.2 Defined protected protocol data unit (PrPDU) types. 43
14.3 Certification authority subscription protocol initialization request . 43
14.4 Certification authority subscription protocol initialization accept . 44
14.5 Certification authority subscription protocol initialization reject . 44
14.6 Certification authority subscription protocol initialization abort . 44
14.7 Public-key certificate subscription request . 44
14.8 Public-key certificate subscription response . 45
14.9 Public-key certificate un-subscription request . 46
14.10 Public-key certificate un-subscription response . 46
14.11 Public-key certificate replacements request . 47
14.12 Public-key certificate replacement response . 48
14.13 End-entity public-key certificate updates request . 49
14.14 End-entity public-key certificate updates response . 49
14.15 Certification authority subscription abort . 50
14.16 Certification authority subscription error codes . 50
15 Trust broker protocol . 51
15.1 Introduction . 51
15.2 Defined protected protocol data unit (PrPDU) types. 51
15.3 Trust broker protocol initialization request . 51
15.4 Trust broker protocol initialization accept . 52
15.5 Trust broker protocol initialization reject . 52
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ISO/IEC 9594-11:2020(E)

Page
15.6 Trust broker protocol initialization abort . 52
15.7 Trust broker request syntax . 52
15.8 Trust broker response syntax . 53
15.9 Trust broker error information . 53
Annex A − Crypto Tools in ASN.1 . 55
Annex B − Wrapper protocol in ASN.1 . 58
Annex C − Protected protocol interface to the wrapper protocol . 63
Annex D − Cryptographic algorithms . 65
Annex E − Authorization and validation list management in ASN.1 . 67
Annex F − Certification authority subscription in ASN.1 . 70
Annex G −Trust broker in ASN.1 . 74
Annex H − Migration of cryptographic algorithms . 76
H.1 Introduction . 76
H.2 Negotiation of cryptographic algorithms . 76
H.3 Non-negotiable digital signature algorithms . 77
Annex I − Auxiliary specifications . 80
Bibliography . 85

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ISO/IEC 9594-11:2020(E)

Introduction
The Internet Engineering Task Force (IETF) maintains a substantial set of protocols for supporting public-key
infrastructure (PKI). Recommendation ITU-T X.510 | ISO/IEC 9594-11 provides protocols to supplement those protocols
developed by IETF, especially for:
a) supporting new functions specified by Rec. ITU-T X.509 | ISO/IEC 9594-8, for which IETF has not
provided support, e.g., support for authorization and validation list (AVL) maintenance;
b) constraint environments, where lean protocols are required.
In addition, it specifies:
c) a wrapper protocol that provides security services for other protocols.
This Recommendation | International Standard consist of three sections as follows.
Section 1 gives general specifications for this Recommendation | International Standard.
Section 2 is the wrapper protocol specification.
Section 3 specifies some protocols to be protected by the wrapper protocol:
a) a protocol for maintaining authorization and validation lists (AVLs);
b) a protocol for subscribing public-key certificate status information from certification authorities (CAs);
and
c) a protocol for accessing a trust broker.
The following annexes are included.
Annex A, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module for
specifications to be imported by protocols providing a migration path for cryptographic algorithms.
Annex B, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module for the
wrapper protocol.
Annex C, which is an integral part of this Recommendation | International Standard, provides specifications for how a
protected protocol is wrapped by the wrapper protocol.
Annex D, which is an integral part of this Recommendation | International Standard, provides cryptographic algorithm
specification.
Annex E, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module for
maintenance of the authorization and validation lists (AVLs) protocol.
Annex F, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module for
certification authority subscription protocol.
Annex G, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module for the
trust broker protocol.
Annex H, which is not an integral part of this Recommendation | International Standard, provides guidance for
cryptographic algorithm migration.
The content of this Rec. ITU-T X.510 | ISO/IEC 9594-11 was moved to here from Rec. ITU-T X.509 (2016) |
ISO/IEC 9594-8:2017 and subsequently updated.
© ISO/IEC 2020 – All rights reserved
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ISO/IEC 9594-11:2020(E)

INTERNATIONAL STANDARD ISO/IEC 9594-11
RECOMMENDATION ITU-T X.510
Information technology – Open Systems Interconnection –
The Directory: Protocol specifications for secure operations
SECTION 1 – GENERAL
1 Scope
The scope of this Recommendation | International Standard is threefold.
This Recommendation | International Standard provides guidance on how to prepare new and old protocols for
cryptographic algorithm migration, and defines auxiliary cryptographic algorithms to be used for migration purposes.
This Recommendation | International Standard specifies a general wrapper protocol that provides authentication, integrity
and confidentiality (encryption) protection for other protocols. This wrapper protocol includes a migration path for
cryptographic algorithms allowing for smooth migration to stronger cryptographic algorithms as such requirements
evolve. This will allow migration to quantum-safe cryptographic algorithms. Protected protocols can then be developed
without taking security and cryptographic algorithms into consideration.
This Recommendation | International Standard also includes some protocols to be protected by the wrapper protocol
primarily for support of public-key infrastructure (PKI). Other specifications, e.g., Recommendations or International
Standards, may also develop protocols designed to be protected by the wrapper protocol.
2 Normative references
The following Recommendations and International Standards contain provisions which, through reference in this text,
constitute provisions of this Recommendation | International Standard. At the time of publication, the editions indicated
were valid. All Recommendations and Standards are subject to revision, and parties to agreements based on this
Recommendation | International Standard are encouraged to investigate the possibility of applying the most recent edition
of the Recommendations and Standards listed below. Members of IEC and ISO maintain registers of currently valid
International Standards. The Telecommunication Standardization Bureau of the ITU maintains a list of currently valid
ITU-T Recommendations.
2.1 Identical Recommendations | International Standards
– Recommendation ITU-T X.500 (2019) | ISO/IEC 9594-1:2020, Information technology - Open Systems
Interconnection - The Directory: Overview of concepts, models and services.
– Recommendation. ITU-T X.501 (2019) | ISO/IEC 9594-2:2020, Information technology – Open Systems
Interconnection – The Directory: Models.
– Recommendation ITU-T X.509 (2019) | ISO/IEC 9594-8:2020, Information technology – Open Systems
Interconnection – The Directory: Public-key and attribute certificate frameworks.
– Recommendation ITU-T X.511 (2019) | ISO/IEC 9594-3:2020, Information technology - Open Systems
Interconnection - The Directory: Abstract service definition.
– Recommendation ITU-T X.518 (2019)
...