Network Working Group S. Nandakumar Internet-Draft C. Jennings Intended status: Standards Track S. Cooley Expires: May 3, 2018 Cisco October 30, 2017 Solution Requirements - Secure Firmware Upgrade (SecFU) draft-nandakumar-suit-secfu-requirements-00 Abstract The IETF SUIT effort has been forming to define a secure firmware upgrade solution for Internet of Things (IOT). Recent vulnerabilities and the need to upgrade firmware on the IoT devices for security updates in a standardized, secure, and automated fashion has been the driving force behind this work. This specification is a requirements document to aid in developing a solution for Secure Firmware upgrade of the IoT devices. 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 May 3, 2018. Copyright Notice Copyright (c) 2017 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 Nandakumar, et al. Expires May 3, 2018 [Page 1] Internet-Draft SecFU October 2017 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 . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Solution Requirements . . . . . . . . . . . . . . . . . . . . 2 3. IANA Consideration . . . . . . . . . . . . . . . . . . . . . 4 4. Security Considerations . . . . . . . . . . . . . . . . . . . 4 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 4 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction This draft outlines a set of requirements around firmware download for IoT devices. A sketch of a proposed solution can be found in . 2. Solution Requirements Informally, a secure firmware upgrade solution might need to address following components: o Secure firmware description container format, in the form of Manifest o Locating a server to download the firmware from o Downloading the manifest and the firmware image(s) o Cryptographic validation of the manifest and signed code images o Complete the installation Given above tasks, this specification breaks down the secure firmware upgrade solution into following requirements: 1. Solution must allow devices that delete the old firmware before installing the new firmware. Thus implying a solution that can easily be implementable on a minimal boot-loader 2. Solution must enable devices that have enough memory to have the new firmware image of the firmware simultaneously loaded with the existing image. 3. The manifest format should be self describing. Nandakumar, et al. Expires May 3, 2018 [Page 2] Internet-Draft SecFU October 2017 4. Allow a given device to decide which manifest format is appropriate for it choosing from JSON, CBOR, or perhaps ASN.1 if there is a a device vendor that plans to use this 5. Manifest must allow metadata about the firmware sourced by a single manufacturer 6. Optionally, the solution may allow the manifest to describe metadata about firmwares from different providers 7. The solution should enable firmware that is delivered as a single image 8. Optionally, the solution may enable firmware to be split into multiple images. 9. The charter should recommend a solution agnostic to the format of the firmware image and inter dependencies. Dependency management is complicated and is by nature proprietary and should not be in the initial scope. 10. The proposed solution must provide mechanism to discover where to download the firmware where that mechanism includes the ability for a local cache. 11. The proposed solution should allow flexibility to choose the underlying transport protocol as defined by the deployment scenarios. The WG should define a MTI set of protocols that firmware servers need to implement and clients can choose which one to use 12. The proposed solution must require a device to validate signatures on the manifest and firmware image(s) 13. Optionally, the solution might want to support encrypted manifest and firmware 14. The proposed solution should enable crypto agility and prevent roll-back attacks. 15. Solution should allow for secure transition between the generations of the keying material 16. Charter should not invent new crypto or transports and use existing techniques Nandakumar, et al. Expires May 3, 2018 [Page 3] Internet-Draft SecFU October 2017 3. IANA Consideration Not Applicable 4. Security Considerations Not Applicable 5. Acknowledgements Thanks IOTSU workshop. Authors' Addresses Suhas Nandakumar Cisco Email: snandaku@cisco.com Cullen Jennings Cisco Email: fluffy@iii.ca Shaun Cooley Cisco Email: scooley@cisco.com Nandakumar, et al. Expires May 3, 2018 [Page 4]