A Firmware Update Architecture for Internet of Things
draft-ietf-suit-architecture-16
SUIT B. Moran
Internet-Draft H. Tschofenig
Intended status: Informational Arm Limited
Expires: July 31, 2021 D. Brown
Linaro
M. Meriac
Consultant
January 27, 2021
A Firmware Update Architecture for Internet of Things
draft-ietf-suit-architecture-16
Abstract
Vulnerabilities in Internet of Things (IoT) devices have raised the
need for a reliable and secure firmware update mechanism suitable for
devices with resource constraints. Incorporating such an update
mechanism is a fundamental requirement for fixing vulnerabilities but
it also enables other important capabilities such as updating
configuration settings as well as adding new functionality.
In addition to the definition of terminology and an architecture this
document motivates the standardization of a manifest format as a
transport-agnostic means for describing and protecting firmware
updates.
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 July 31, 2021.
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Internet-Draft A Firmware Update Architecture for IoT January 2021
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 5
2.1. Terms . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2. Stakeholders . . . . . . . . . . . . . . . . . . . . . . 6
2.3. Functions . . . . . . . . . . . . . . . . . . . . . . . . 7
3. Architecture . . . . . . . . . . . . . . . . . . . . . . . . 8
4. Invoking the Firmware . . . . . . . . . . . . . . . . . . . . 13
4.1. The Bootloader . . . . . . . . . . . . . . . . . . . . . 14
5. Types of IoT Devices . . . . . . . . . . . . . . . . . . . . 15
5.1. Single MCU . . . . . . . . . . . . . . . . . . . . . . . 16
5.2. Single CPU with Secure - Normal Mode Partitioning . . . . 16
5.3. Symmetric Multiple CPUs . . . . . . . . . . . . . . . . . 16
5.4. Dual CPU, shared memory . . . . . . . . . . . . . . . . . 16
5.5. Dual CPU, other bus . . . . . . . . . . . . . . . . . . . 17
6. Manifests . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7. Securing Firmware Updates . . . . . . . . . . . . . . . . . . 19
8. Example . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25
10. Security Considerations . . . . . . . . . . . . . . . . . . . 25
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 25
12. Informative References . . . . . . . . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 28
1. Introduction
Firmware updates can help to fix security vulnerabilities, and
performing updates is an important building block in securing IoT
devices. Due to rising concerns about insecure IoT devices the
Internet Architecture Board (IAB) organized a 'Workshop on Internet
of Things (IoT) Software Update (IOTSU)' [RFC8240] to take a look at
the bigger picture. The workshop revealed a number of challenges for
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