Getting Started with Secure Embedded Systems

Build secure and reliable IoT applications for micro:bit and Raspberry Pi Pico by using Rust and Tock.

One of the first Operating Systems written in Rust, Tock is designed to safely run multiple applications on low power devices, enabling you to build a secure foundation for IoT systems. It is an open-source OS that has recently gained popularity as companies such as Google[1] explore and integrate it into their products.

This book guides you through the steps necessary to customize and integrate Tock into your devices. First, you'll explore the characteristics of Tock and how to run it on two of the most popular IoT platforms: micro:bit and Raspberry Pi Pico. You’ll also take a look at Rust and how to use it for building secure applications with Tock.

The book focuses on the Tock kernel internals and presents the steps necessary to integrate new features. From simple drivers to the more complex asynchronous ones, you are provided with a detailed description of the Tock kernel API.

Next, you'll review the Tock applications framework for C. Starting from simple Tock APIs to the more complex Inter-Process Communication system, this book provides a complete overview of the Tock application ecosystem.

By taking a practical approach, Getting Started with Secure Embedded Systems provides a starting point for building a secure IoT foundation using the Tock Operating System.

YOU WILL:

* Use Rust for embedded systems development
* Write applications and drivers for Tock
* Customize the Tock kernel for specific hardware platforms
* Set a solid base for building secure and reliable IoT applications
Use Tock to ensure the security of your microcontrollers and integrate them into your projects * Manage products that rely on Tock

WHO THIS BOOK IS FOR

IoT system designers, developers, and integrators who are familiar with operating systems concepts. The book can also be suitable for people with less experience, who want to gain an overview of the latest hardware and software technologies related to building secure IoT systems.

ALEXANDRU RADOVICI has a PhD in the field of mobile computing and works as an Assistant Professor at the Politehnica University of Bucharest, teaching subjects related to operating systems, compilers and Internet of Things. Alexandru believes in the power of education and teaching is his passion, so 14 years ago he founded an NGO that focuses on organizing IT educational events. Alexandru is also the co-founder and CTO of Wyliodrin, being in touch with the latest IoT technologies. Alexandru has been a contributor to Tock, adding boards such as the STM32 Discovery Kit and adding support for screens and touch screens.

IOANA CULIC is currently a PhD candidate in the field of Internet of Things and the co-founder of Wyliodrin, a company that offers educational and industrial IoT solutions. She is a Teaching Assistant at the Politehnica University of Bucharest and has also been teaching IoT technologies to high-school and university students at different events for the last five years. Despite the technical background, writing has always been Ioana’s passion and she managed to mix the two. She has published several articles in magazines such as the MagPi and Make Magazine and books on Internet of Things technologies. Ioana has been porting JavaScript to Tock.

CHAPTER 1: Introduction to Embedded Operating Systems

● FreeRTOS

● RIOT OS

● Zephyr

● Mbed OS

● Why is TockOS new and different?

CHAPTER 2: Modern Low Power Microcontrollers

● Main functional components of modern microcontrollers

● Processing unit

o ARM Cortex-M

o RISC-V IMC and IMAC

● General memory layout

● Persistent storage

● Communications busses

● Debug

CHAPTER 3: The TockOS System Architecture

● Architecture

● Memory Layout

● Kernel

○ Hardware Abstraction Layer

○ Capsules

● Applications

● Flashing the system

● Examples

CHAPTER 4: Running TockOS

● Preparing the tools

● Understanding the kernel’s source code

● Compiling the kernel

● Understanding the user land application source code

● Compiling an application

● Running using an emulator (RISC-V)

● Running using a real device (STM32F412)

CHAPTER 5: Writing Applications

● TockOS System calls

● The TockOS API library

● Adding a third-party library

● Building for several architectures

● TockOS Application Distribution

CHAPTER 6: Rust for TockOS

● Introduction to Rust

● Lifetimes

● Mutable references

CHAPTER 7: Writing a capsule

● Capsule architecture

● Asynchronous API

● The Hardware Interface Layer

● Using a timer (for delays)

● System calls implementation

● Writing a component

● Using the capsule from an application

CHAPTER 8: Writing a Sensor Capsule

● Sensor HILs

● Virtual Device Interfaces

● Using the ADC device

● Implementing the system calls

● Using the capsule from an application

CHAPTER 9: Using Communication Busses

● UART

● SPI

● i2C

● BLE

● Basic Networking

CHAPTER 10: Building for a Custom System

● Creating a new board

● Memory layout

● Adding capsules

● Enabling and setting up hardware

● Starting the kernel

CHAPTER 11: Designing a Hardware Interface Layer

● The HIL trait

● Designing the HIL

CHAPTER 12: Porting TockOS

● The microcontroller architecture

o MPU setup

o interrupts

o bootstrapping

● The chip

o The interrupt vector

o Enabling peripherals

o Implementing basic HILs

CHAPTER 13: Contributing to TockOS

● Creating a Pull Request

● Automatic testing

● Review process