Internet DRAFT - draft-richardson-6tisch-idevid-cert
draft-richardson-6tisch-idevid-cert
Network Working Group M. Richardson
Internet-Draft SSW
Intended status: Informational March 26, 2015
Expires: September 27, 2015
X509.v3 certificate extension for authorization of device ownership
draft-richardson-6tisch-idevid-cert-01
Abstract
This document details an X.509 extension to provide authorization and
indication of ownership of a constrained device containing 802.1AR
IDevID.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 27, 2015.
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Richardson Expires September 27, 2015 [Page 1]
Internet-Draft 6tisch-security March 2015
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . 3
2. Autonomous System Identifier Delegation Extension . . . . . 4
2.1. Context . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Specification . . . . . . . . . . . . . . . . . . . . . 4
2.2.1. Criticality . . . . . . . . . . . . . . . . . . . . 5
2.2.2. Syntax . . . . . . . . . . . . . . . . . . . . . . . 5
2.2.3. Type IDevID . . . . . . . . . . . . . . . . . . . . 5
2.2.4. Elements asnum, rdi, and Type ASIdentifierChoice . . 5
2.2.5. Element inherit . . . . . . . . . . . . . . . . . . 6
2.2.6. Element asIdsOrRanges . . . . . . . . . . . . . . . 6
2.2.7. Type ASIdOrRange . . . . . . . . . . . . . . . . . . 6
2.2.8. Element id . . . . . . . . . . . . . . . . . . . . . 6
2.2.9. Element range . . . . . . . . . . . . . . . . . . . 6
2.2.10. Type IDevIDRange . . . . . . . . . . . . . . . . . . 6
2.2.11. Elements min and max . . . . . . . . . . . . . . . . 6
2.2.12. Type IDevId . . . . . . . . . . . . . . . . . . . . 6
2.3. Autonomous System Identifier Delegation Extension
Certification . . . . . . . . . . . . . . . . . . . . . . 7
3. Security Considerations . . . . . . . . . . . . . . . . . . 7
4. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 7
5. Appendix A -- ASN.1 Module . . . . . . . . . . . . . . . . . 7
6. Appendix C -- Example of an AS Identifier Delegation
Extension . . . . . . . . . . . . . . . . . . . . . . . . . . 8
7. Normative References . . . . . . . . . . . . . . . . . . . . 8
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 8
1. Introduction
This document defines two X.509 v3 certificate extensions that
authorize the transfer of the right-to-use for a set of devices
identified by 802.1AR IDevID from a production Factory through
national and regional distributors (VARs) to Plant Owners/Operators.
This extension binds a list of IDevID identifiers to the subject
(private key holder) of a certificate. The issuer of the certificate
is an entity (e.g., a Factory) that has produced the device to to
transfer ownership set of IDevID to the subject of the certificate.
These certificates provide a scalable, no-touch means of verifying
the ownership of a constrainted device. The constrained is
initialized with the trusted certificate of the Factory at the
Factory. This process may be used by enrollment protocols such as
1x, PANA, EAP-TLS and RPL to validate that the network infrastructure
being presented is the legitimate infrastructure for the constrainted
device.
Richardson Expires September 27, 2015 [Page 2]
Internet-Draft 6tisch-security March 2015
Sections 2 specify several rules about the encoding of the extensions
defined in this specification that MUST be followed. These encoding
rules serve the following purposes. First, they result in a unique
encoding of the extension's value; two instances of an extension can
be compared for equality octet-by-octet. Second, they achieve the
minimal size encoding of the information. Third, they allow relying
parties to use one-pass algorithms when performing certification path
validation; in particular, the relying parties do not need to sort
the information, or to implement extra code in the subset checking
algorithms to handle several boundary cases (adjacent, overlapping,
or subsumed ranges).
1.1. Terminology
It is assumed that the reader is familiar with the terms and concepts
described in "Internet X.509 Public Key Infrastructure Certificate
and Certificate Revocation List (CRL) Profile" [RFC3280], "INTERNET
PROTOCOL" [RFC791], "Internet Protocol Version 6 (IPv6) Addressing
Architecture" [RFC3513], "INTERNET REGISTRY IP ALLOCATION GUIDELINES"
[RFC2050], and related regional Internet registry address management
policy documents. Some relevant terms include:
allocate - the transfer of custodianship of a resource to an
intermediate organization (see [RFC2050]).
assign - the transfer of custodianship of a resource to an end
organization (see [RFC2050]).
Autonomous System (AS) - a set of routers under a single technical
administration with a uniform policy, using one or more interior
gateway protocols and metrics to determine how to route packets
within the autonomous system, and using an exterior gateway protocol
to determine how to route packets to other autonomous systems.
Autonomous System number - a 32-bit number that identifies an
autonomous system.
delegate - transfer of custodianship (that is, the right-to-use) of
an IP address block or AS identifier through issuance of a
certificate to an entity.
initial octet - the first octet in the value of a DER encoded BIT
STRING [X.690].
IDevID - a variable octet identifier written as in hexadecimal.
While there is no length limit to the IDevID, a Factory is expected
to pick a particularly length and stick to that length so that the
IDevID can be aggregated by simple integer enumeration.
Richardson Expires September 27, 2015 [Page 3]
Internet-Draft 6tisch-security March 2015
subsequent octets - the second through last octets in the value of a
DER encoded BIT STRING [X.690].
trust anchor - a certificate that is to be trusted when performing
certification path validation (see [RFC3280]).
The keywords MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT, SHOULD,
SHOULD NOT, RECOMMENDED, and MAY, and OPTIONAL, when they appear in
this document, are to be interpreted as described in [RFC2119].
2. Autonomous System Identifier Delegation Extension
This extension conveys the delegation of ownership of a device
identified by an 802.1AR Device ID to an entity by binding those
IDevID to a public key belonging to the entity.
2.1. Context
802.1AR defines a mechanism by which a manufacturer may place a
certificate that attests to the a device's identity into the device
at manufacturer time. This mechanism permits a device to
cryptographically identify itself to a network. The device, however
is unable to know to which network it belongs. This extension
permits the manufacturer, using the same trusted anchor to delegate
ownership of the device to the end user (possibly via a series of
intermediaries, such as a supplier chain). The use of such a
certificate chain can be easily verified by the device, and
therefore, combined with 802.1AR, permits mutual authentication of
devices and network entities.
2.2. Specification
The OID for this extension is id-pe-iDevID.
id-pe-iDevID OBJECT IDENTIFIER ::= { id-pe IANA-TBD }
where [RFC3280] defines:
id-pkix OBJECT IDENTIFIER ::= { iso(1) identified-organization(3)
dod(6) internet(1) security(5) mechanisms(5) pkix(7) }
id-pe OBJECT IDENTIFIER ::= { id-pkix 1 }
Figure 1: OID
Richardson Expires September 27, 2015 [Page 4]
Internet-Draft 6tisch-security March 2015
2.2.1. Criticality
This extension SHOULD be CRITICAL. The intended use of this
extension is to connote an ownership of the device specified in the
extension. A CA marks the extension as CRITICAL to convey the notion
that a relying party must understand the semantics of the extension
to make use of the certificate for the purpose it was issued. Newly
created applications that use certificates containing this extension
are expected to recognize the extension.
2.2.2. Syntax
id-pe-iDevID OBJECT IDENTIFIER ::= { id-pe IANA_TBD }
IDevID ::= SEQUENCE { idevnum [0] EXPLICIT
IDevIDChoice OPTIONAL,
rdi [1] EXPLICIT ASIdentifierChoice OPTIONAL
}
IDevIDChoice ::= CHOICE { inherit NULL, -- inherit from issuer --
iDevIdsOrRanges SEQUENCE OF iDevIdOrRange
}
IDevIdOrRange ::= CHOICE { id IDevId, range IDevRange }
IDevRange ::= SEQUENCE { min IDevId, max IDevId }
IDevId ::= INTEGER
Figure 2: OID
2.2.3. Type IDevID
The IDevID type is a SEQUENCE containing one or more forms of Device
Identifiers-- IDevID numbers (in the idevnum element) or routing
domain identifiers (in the rdi element). When the IDevID type
contains multiple forms of identifiers, the idevnum entry MUST
precede the rdi entry. IDevID numbers are used by 802.1AR and are
specified there.
2.2.4. Elements asnum, rdi, and Type ASIdentifierChoice
The idevnum and rdi elements are both of type IDevIDChoice. The
IDevIDChoice type is a CHOICE of either the inherit or asIdsOrRanges
element.
XXX - But I don't think we need this CHOICE
Richardson Expires September 27, 2015 [Page 5]
Internet-Draft 6tisch-security March 2015
2.2.5. Element inherit
If the IDevIDChoice choice contains the inherit element, then the set
of authorized IDevIDs is taken from the issuer's certificate, or from
the issuer's issuer's certificate, recursively, until a certificate
containing an IDevIDChoice containing an iDevIdsOrRanges element is
located. If no authorization is being granted for a particular form
of IDevID, then there MUST NOT be a corresponding idevnum/rdi member
in the IDevID sequence.
2.2.6. Element asIdsOrRanges
The asIdsOrRanges element is a SEQUENCE of ASIdOrRange types. Any
pair of items in the asIdsOrRanges SEQUENCE MUST NOT overlap. Any
contiguous series of AS identifiers MUST be combined into a single
range whenever possible. The AS identifiers in the asIdsOrRanges
element MUST be sorted by increasing numeric value.
2.2.7. Type ASIdOrRange
The ASIdOrRange type is a CHOICE of either a single integer (IDevId)
or a single sequence (IdevIDRange).
2.2.8. Element id
The id element has type ASId.
2.2.9. Element range
The range element has type ASRange.
2.2.10. Type IDevIDRange
The IDevIDRange type is a SEQUENCE consisting of a min and a max
element, and is used to specify a range of IDevID identifier values.
2.2.11. Elements min and max
The min and max elements have type IDevID. The min element is used
to specify the value of the minimum IDevID identifier in the range,
and the max element specifies the value of the maximum IDevID
identifier in the range.
2.2.12. Type IDevId
The IDevId type is an INTEGER. XXX - this will need work
Richardson Expires September 27, 2015 [Page 6]
Internet-Draft 6tisch-security March 2015
2.3. Autonomous System Identifier Delegation Extension Certification
Path Validation
Certification path validation of a certificate containing the
autonomous system identifier delegation extension requires additional
processing. As each certificate in a path is validated, the AS
identifiers in the autonomous system identifier delegation extension
of that certificate MUST be subsumed by the AS identifiers in the
autonomous system identifier delegation extension in the issuer's
certificate. Validation MUST fail when this is not the case. A
certificate that is a trust anchor for certification path validation
of certificates containing the autonomous system identifier
delegation extension, as well as all certificates along the path,
MUST each contain the autonomous system identifier delegation
extension. The initial set of allowed AS identifiers is taken from
the trust anchor certificate.
3. Security Considerations
This specification describes an X.509 extension. Since X.509
certificates are digitally signed, no additional integrity service is
necessary. Certificates with these extensions need not be kept
secret, and unrestricted and anonymous access to these certificates
has no security implications.
However, security factors outside the scope of this specification
will affect the assurance provided to certificate users. This
section highlights critical issues that should be considered by
implementors, administrators, and users.
This extensions represent authorization information, i.e., a right-
to-use/ownership statement for a device. They were developed to
support zero-touch autonomic configuration of constrained devices in
a sensor network. As a result of this capability model, the Subject
field is largely irrelevant for security purposes, contrary to common
PKI conventions.
4. Acknowledgments
This document was cribbed extensively from RFC3779, however, errors
were introduced here.
5. Appendix A -- ASN.1 Module
This normative appendix will describes the IDevID extensions used by
conforming PKI components in ASN.1 syntax.
Richardson Expires September 27, 2015 [Page 7]
Internet-Draft 6tisch-security March 2015
6. Appendix C -- Example of an AS Identifier Delegation Extension
A critical X.509 v3 certificate extension that specifies:
7. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
Author's Address
Michael C. Richardson
Sandelman Software Works
470 Dawson Avenue
Ottawa, ON K1Z 5V7
CA
Email: mcr+ietf@sandelman.ca
URI: http://www.sandelman.ca/
Richardson Expires September 27, 2015 [Page 8]
