SUIT Working Group H. Birkholz
Internet-Draft Fraunhofer SIT
Intended status: Standards Track July 18, 2018
Expires: January 19, 2019

A SUIT Manifest Extension for Concise Software Identifiers
draft-birkholz-suit-coswid-manifest-00

Abstract

This document defines a resource extension for Concise Software Identifiers (CoSWID) that represents a SUIT firmware manifest. This extension combines the information elements of the SUIT information model with the semantic expressiveness of Software Identifiers. In consequence, this composite enables the integration of Firmware Updates for the Internet of Things (SUIT) in existing work-flows for updates of software components in general.

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 https://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 January 19, 2019.

Copyright Notice

Copyright (c) 2018 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 (https://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.


Table of Contents

1. Introduction

Firmware updates are quite similar to software update of applications – composites of software components – for example, servers or user-devices. Attributes and semantic dependencies as defined by Concise Software Identifies [I-D.ietf-sacm-coswid] are equivalent. In contrast, location and target definitions as well as the characteristics that are specific to an update campaign of a SUIT require a specific set of addiction information elements. The semantics regarding SUIT specific information elements are defined by the SUIT Information Model [I-D.ietf-suit-information-model]. Correspondingly, the CoSWID extension defined in this document uses CDDL extension points to add SUIT information elements to the standard Concise Software Identifiers.

The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “NOT RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.

2. SUIT Manifest Extension

The following CDDL data definition is intended to be used as an extension to the CoSWID CDDL data definition. Corresponding terms, such as Resources, Processors and Targets of input nodes and output nodes are covered by the SUIT Information Model and Architecture [I-D.ietf-suit-architecture].

3. SUIT Manifest Resource Data Definition

The following CDDL data definition MUST be added to Payload or Evidence Resources via CDDL extension points in order to express SUIT Manifests in Concise Software Identifiers.

$$payload-extension  //= (suit.manifest-entry,)
$$evidence-extension  //= (suit.manifest-entry,)

suit-manifest = {
  suit.manifest-version,
  suit.digest-info,
  suit.text-reference,
  suit.nonce,
  suit.sequence-number,
  ? suit.pre-condition,
  ? suit.post-condition,
  ? suit.directives,
  ? suit.resources,
  ? suit.processors,
  ? suit.targets,
  ? suit.extensions,
}

suit.manifest-entry = (59: suit-manifest / [ 2* suit-manifest ] )
suit.manifest-version = (60: 1)
suit.digest-info = (61: [ suit.digest-algorithm,
                          ? suit.digest-parameters,
                        ]
                   )
suit.digest-algorithm = uint
suit.digest-parameters = bytes
suit.text-reference = (62: bytes)
suit.nonce = (63: bytes)
suit.sequence-number = (64: uint)
suit.pre-condition = (suit.id-condition // suit.time-condition // suit.image-condition // suit.custom-condition)
suit.post-condition = (suit.image-condition // suit.custom-condition)
suit.id-condition = (65: [ + [ suit.vendor / suit.class / suit.device,
                               suit.uuid,
                             ]
                         ]
                    ) 
suit.vendor = 0
suit.class = 1
suit.device = 2
suit.uuid = bstr .size 16
suit.time-condition = (66: [ + [ suit.install-after / suit.best-before,
                                 suit.timestamp,
                               ]
                           ]
                      )
suit.install-after = 0
suit.best-before = 1
suit.timestamp = uint .size 8
suit.image-condition = (67: [ + [ suit.current-content / suit.not-current-content,
                                  suit.storage-identifier,
                                  ? suit.digest,
                                ]
                            ]
                       )
suit.current-content = 0
suit.not-current-content = 1
suit.digest = bytes
suit.storage-identifier = bytes
suit.custom-condition = (68: [ nint,
                               suit.condition-parameters,
                             ]
                        )
suit.condition-parameters = bytes
suit.directives = (69: { + int => bytes } )
suit.resources = (70: [ + [ suit.resource-type,
                            suit.uri-list,
                            suit.digest,
                            suit.onode,
                            ? suit.size,
                          ]
                      ] 
                 )
suit.resource-type = suit.payload / suit.dependency / suit.key / suit.alias
suit.payload = 0
suit.dependency = 1
suit.key = 2
suit.alias = 3
suit.uri-list = { + int => text }
suit.size = uint
suit.onode = bytes
suit.processors = (71: [ + [ suit.decrypt / suit.decompress / suit.undiff / suit.relocate / suit.unrelocate,
                             suit.parameters,
                             suit.inode,
                             suit.onode,
                           ]
                       ]
                  )
suit.decrypt = 0
suit.decompress = 1
suit.undiff = 2
suit.relocate = 3
suit.unrelocate = 4
suit.parameters = bytes
suit.inode = bytes
suit.targets = (72: [ + [ suit.component-id,
                          suit.storage-identifier,
                          suit.inode,
                          ? suit.encoding,
                        ]
                    ]
                )
suit.component-id = [ + bytes ]
suit.encoding = bytes
suit.extensions = (73: { + int => bytes } )

4. Future Updates

This draft is intended to incorporate the extension registry that will be defined by Concise Software Identifiers. Until then, a consecutive numbering system in alignment to the labels used in Concise Software Identifiers is applied.

5. Security Considerations

TBD

6. Acknowledgments

TBD

7. Change Log

Initial Contribution

8. Contributors

TBD

9. Normative References

[I-D.ietf-sacm-coswid] Birkholz, H., Fitzgerald-McKay, J., Schmidt, C. and D. Waltermire, "Concise Software Identifiers", Internet-Draft draft-ietf-sacm-coswid-06, July 2018.
[I-D.ietf-suit-architecture] Moran, B., Meriac, M., Tschofenig, H. and D. Brown, "A Firmware Update Architecture for Internet of Things Devices", Internet-Draft draft-ietf-suit-architecture-01, July 2018.
[I-D.ietf-suit-information-model] Moran, B., Tschofenig, H. and H. Birkholz, "Firmware Updates for Internet of Things Devices - An Information Model for Manifests", Internet-Draft draft-ietf-suit-information-model-01, July 2018.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017.

Author's Address

Henk Birkholz Fraunhofer SIT Rheinstrasse 75 Darmstadt, 64295 Germany EMail: henk.birkholz@sit.fraunhofer.de