Mbed TLS − KBOOT • Overview of Methods • Development Steps • Key Management Options • Resources and Next Steps

How to protect your firmware against malicious attacks using the latest Kinetis development board

April 25, 2017

IoT and Security Solutions

PUBLIC PUBLIC 0 Agenda • IoT Phishing: “I have a bad feeling about this…” • Applying a security model • NXP Kinetis MCU solution − Kinetis K28F MCU − mbed TLS − KBOOT • Overview of methods • Development steps • Key management options • Resources and next steps

PUBLIC 2 1 IoT: Phishing with Edge Nodes

PUBLIC 3 3 Driving Internet of Things (IoT) Innovation

Society Data centers Vehicle

Cities Transactions

PUBLIC 4 Phishing with IoT Edge Node Lures – A new attack vector to prepare for.

• By now, people from all walks of life are aware of email phishing scams that are used to inject malware onto personal computing devices. • But what about a phishing attack that uses an IoT edge node as a lure? • How can this happen?

End node that has been tampered with to contain malicious firmware Attacker access to network interfaces leading to additional breaches or User dDoS acceptance and provisioning of the device with secret data PUBLIC 5 2 Applying a Security Model

PUBLIC 6 Begin with a Security Model

• The rules in place that identify the data that should be protected • For example • The management of firmware, secret keys, user and application data Policies • Passwords, personal information, network credentials

• The definition of the attacks and attackers that the end device will face and protect against • Considers the access to the device, and cost of the attack Threat • For example • Expert attackers who will use off the shelf tools to gain access and insert malware landscape

• The means by which the policies for the device are enforced • Involves the application of security technology to achieve product goals • For example Methods • Protecting secret keys with tamper response using the Kinetis MCU anti-tamper

PUBLIC 7 A Security Model | Methods Security Technology: Hardware View

Threat Policies Methods Landscape

• Crypto Acceleration

− ‘mmCAU’, for low-end Kinetis Only − ‘LTC’, for high-end Kinetis authenticated − ‘CAAM’ for i.MX firmware • Trusted Execution ® should be − ARM TrustZone − ‘Secure boot executed − ‘RTIC’ (Runtime Integrity Checker)

− Secure debug Physical access to − Secure storage − Resource domain isolation (MPU, FAC) the device • Tamper Resistance communication ports − Erases secrets at tamper detect

− Active and passive tampers

PUBLIC 8 Security Technology | Secure Boot System View

Authenticated Application code Manufacturing Development Tool chain, Key management, Code Unchangeable Boot Code Signing tools RTOS Cryptography Stack Bootloader Code Confidentiality and/or Boot interfaces, Command parser, Middleware Authentication Memory programming

SDK Low Level Drivers SDK Deployment Trusted configurations for chip firewalls and interfaces for protection of resources Application tool chain, Host programmer Hardware providing physical & logical security MCU features for trust, crypto and anti-tamper

PUBLIC 9 3 NXP Kinetis MCU Solution

PUBLIC 10 10 Kinetis K27/K28 USB MCUs Industry’s Largest Embedded SRAM Memory on ARM® Cortex®-M4-based MCU, Optimized for Portable Devices

Largest Embedded SRAM • 1MB of embedded SRAM plus 2MB of Flash memory to enable longer battery life and richer graphics in portable display applications Lower System Power • 150 MHz Kinetis MCU enables advanced integration in battery-operated applications Advanced Integration • Reduces system board footprint required by wearables and other low-end graphic display systems Complete Enablement • Low-cost FRDM-K28F development platform, optional 5” LCD display board with capacitive touch from MikroElektronika, MCUXpresso software and tools

PUBLIC 11 Kinetis K27F/K28F HW and SW Enablement Plan

K28F ADDS-ON BASELINE SW OPTIONAL BORAD HW BOARD HW BOARDS SW ENABLEMENT ENABLEMENT FEATURES CONNECTOR Kinetis SDK 2.x FRDM-KW41Z Arduino IDE: BLE + IAR BLE stack running on KW41Z (UART) • MCUXPresso IDE + FreeRTOS • IAR Arrow GT202 QCA4002 Wi-Fi drivers to be Arduino WI-FI • KEIL Wi-Fi stack running on QCA4002 ported to Kinetis SDK 2.x (UART) Kinetis SDK 2.x (TBD) FRDM-K28F FRDM-KW24D512 or FRDM-KW41Z + FreeRTOS Arduino THREAD SW Stack running on KWx wireless SoC + IAR (UART) RTOS: Low-cost evaluation + NXP Thread SW SDK • FreeRTOS platform for K27F/K28F family Bare metal (no RTOS) MikroElectronika MCUXPresso SDK 2.x with on-board discrete power LCD 5' LCD display + capacitive touch + MicroEJ (3rd party) SW support FlexIO management, Accelerometer, DISPLAY connected through FlexIO interface + emWIN (3rd party) SW support SDRAM memory, QuadSPI (8080 and/or 6800 modes) Kinetis Expert: Serial Flash, USB High-Speed • Power Estimator tool FRDM-STBC-AGM01 (Sensor Fusion) Kinetis SDK 2.x (TBD) connector and Full-Speed USB Arduino • Pin Configuration tool SENSOR 9-axis inertial measurement solution: + FreeRTOS/Bare Metal OpenSDA (I2C / SPI) • Clock Configuration tool 3-axis Gyro, 3D Accelero + Magneto + Sensing SDK 1.0 • Peripheral configuration ARD-AUDIO-DA7212 Target resale price: $40 2-channel audio codec w/ capless Arduino tool AUDIO Kinetis SDK 2.x (TBD) headphone driver and 3.5mm stereo (I2S) AUX input jack socket NXP HomeKit SDK 1.x MCUXPresso SDK 2.x HOMEKIT FRDM-TWRPI + TWRPI-I2C* + Kinetis SDK 1.3 Arduino & MFI MFi Adaptor boards + FreeRTOS (I2C) + IDE (IAR or KDS)

PUBLIC 12 Security Technology | System view : Hardware

SDK Low Level Drivers SDK Deployment Trusted configurations for chip firewalls and interfaces for protection of resources Application tool chain, Host programmer Kinetis K28F Hardware Features: Flash Security, Flash Block Protection, HW acceleration for SHA256 and AES, TRNG

PUBLIC 13 Kinetis Low Power 32-bit MCs Based on ARM® Cortex®-M Cores

PUBLIC 14 Kinetis Security Technology | Essential Hardware Features

• Flash security and protection features are found on all Kinetis devices • Security features − Kinetis offers several levels of flash security − Flash security is a system-level feature ▪ The flash is fully functional when secured (firmware updates are still possible if resident firmware is setup to program the flash) ▪ Security effects are really a system level concern. The security setting determines what the SoC will allow. − Software IP is a large investment. Enabling security helps to protect that IP investment.

• Protection features − Flash protection can be used to prevent erase or programming − Initial protection values are loaded from the flash configuration field at reset

PUBLIC 15 Flash Block Protections to Protect Boot Code

0x0000_0000 Program Flash size / 32 FPROT3[PROT0]

Program Flash size / 32 FPROT3[PROT1]

Program Flash size / 32 FPROT3[PROT2]

*** *** ***

Program Flash size / 32 FPROT0[PROT30]

0x0020_0000 Program Flash size / 32 FPROT0[PROT31]

PUBLIC 16 Security Technology | System View : SDK & Toolchain

Authenticated Application code

Manufacturing MCUXpresso IDE, Key management, Code Signing tools Unchangeable Boot Code RTOS Cryptography Stack Bootloader Code Confidentiality and/or Boot interfaces, Command parser, Middleware Authentication Memory programming

MCUXpresso SDK SDK Deployment Application tool chain, Host programmer Kinetis K28F Hardware Features: Flash Security, Flash Block Protection, HW acceleration for SHA256 and AES, TRNG

PUBLIC 17 Tool Chain and Software Feature-rich, unlimited code size, optimized for ease-of-use, based on industry standard Eclipse framework MCUXpresso Software and Tools for NXP’s Kinetis and LPC MCUs for Kinetis and LPC microcontrollers Application development with Eclipse and GCC-based IDE for advanced editing, compiling and debugging MCUXpresso IDE Supports custom development Available Edit, compile, debug and optimize in an boards, Freedom, Tower and now! intuitive and powerful IDE LPCXpresso boards with debug probes from NXP, P&E and Segger

Free Edition: Full Featured, unlimited MCUXpresso SDK Code Size, no special activation Available Runtime software including peripheral needed, community based support now! drivers, middleware, RTOS, demos and Pro Edition: Email IDE support, more Advanced Trace Features

MCUXpresso Config Tools Available now! Online and desktop tool suite for system configuration and optimization

PUBLIC 18 Tool Chain and Software

MCUXpresso Software and Tools for Kinetis and LPC microcontrollers

Architecture: MCUXpresso IDE ▪ CMSIS-CORE compatible Available ▪ Single driver for each peripheral now! Edit, compile, debug and optimize in an ▪ Transactional APIs w/ optional DMA intuitive and powerful IDE support for communication peripherals

Integrated RTOS: MCUXpresso SDK ▪ FreeRTOS v9 ▪ RTOS-native driver wrappers Available Runtime software including peripheral now! drivers, middleware, RTOS, demos and more Integrated Stacks and Middleware ▪ USB Host, Device and OTG ▪ lwIP, FatFS ▪ Crypto acceleration plus wolfSSL & MCUXpresso Config Tools mbedTLS Available ▪ SD and eMMC card support now! Online and desktop tool suite for system configuration and optimization

PUBLIC 19 Security Technology | System View : Cryptography Stack

Authenticated Application code

Manufacturing MCUXpresso IDE, Key management, Code Signing tools Unchangeable Boot Code RTOS mbed TLS Bootloader Public Key/Private Key Generation, Boot interfaces, Command parser, Middleware Signature Generation &Verification Memory programming

MCUXpresso SDK SDK Deployment Application tool chain, Host programmer Kinetis K28F Hardware Features: Flash Security, Flash Block Protection, HW acceleration for SHA256 and AES, TRNG

PUBLIC 20 Support For Use of HW Accelerators with mbed TLS

PUBLIC 21 mbed TLS

PUBLIC 22 https://tls.mbed.org/high-level-design https://tls.mbed.org/module-level-design-public-key

PUBLIC 23 https://tls.mbed.org/core-features

Scalable Security Level Align to HW Capabilities & Security levels

PUBLIC 24 mbed TLS file Structure Allows Lightweight Implementations

PUBLIC 25 Security Technology | System View: Bootloader and Tools

Manufacturing Authenticated Application code MCUXpresso IDE, Key management, Code Signing tools (Kinetis hardware with Unchangeable Boot Code KBOOT and host RTOS tools) mbed TLS KBOOT Public Key/Private Key Generation, Boot interfaces, Command parser, Middleware Signature Generation &Verification Memory programming

MCUXpresso SDK SDK Deployment Application tool chain, Host programmer Kinetis K28F Hardware Features: Flash Security, Flash Block Protection, HW acceleration for SHA256 and AES, TRNG

PUBLIC 26 KBOOT: Kinetis Bootloadercccccc

HOST TOOLS: Kinetis Flash Tool, blhost, elftosb, Kinetis MCU Host

PUBLIC 27 HOST TOOLS: Kinetis Flash Tool, blhost, elftosb, Kinetis MCU Host

Elftosb : Command line Graphical user Kinetis K66 processing of program that interface to application that binaries, elf and interfaces to a interface to a performs host

SREC files into Blhost Kinetis MCU Kinetis MCU functionality to a Elftosb secure binaries running KBOOT running KBOOT Kinetis MCU (Special formats running KBOOT to work with KBOOT) Supports every Easier to use than KBOOT command blhost, but not as

Capable of powerful Kinetis Flash Tool Kinetis Flash encrypting files, Kinetis MCU Host generating keys

The Elftosb and blhost tool is command line driven and can be separately built to run on Windows® OS, Linux® OS, and Apple Mac® OS.

PUBLIC 28 KBOOT Definitions and Use

• BD file: Short for boot descriptor file. This is an input command file to be used by elftosb for created SB files • SB file: Short for secure binary file. This is the output of elftosb which is used to pass commands and data to a Kinetis MCU running KBOOT Input files

Input files Keys for Firmware encrypt

SREC USB FS K28F HW blhost with KBOOT Binary elftosb SB file

ELF

Input files Commands

BD file PUBLIC 29 4 Overview of Methods

PUBLIC 30 30 Using KBOOT for Signature Generation

• Factory KBOOT application • Production KBOOT application − This bootloader application is for use in a − This bootloader application is for use in a secure manufacturing environment. The deployed device. The main security main security functions in addition to functions in addition to bootloader bootloader functions are to generate a functions are to check the signature of PUB/PRIV key pair and to generate the application code using the public key, signature for application code using the and only allow execution of the application private key. code if the signature is authentic. K28F Hardware Production KBOOT HW for KBOOT Factory Application

HOST TOOLS: Kinetis Flash Tool, blhost, elftosb, Kinetis MCU Host

PUBLIC 31 Overview of the Method

• Typical Application Development • Final production image

0x0000_0000 0x0000_0000 KBOOT Your IoT Protected 0x0000_8000 Public key Application mbed TLS Unchangeable code 0x0000_FFFF (Cryptography)

0x0001_0000 Manufacturing Your IoT application code

0x0020_0000 0x0020_0000 Signature

PUBLIC 32 Overview of the Method

• Typical Application Development • Final production image

0x0000_0000 0x0000_0000 KBOOT KBOOT Your IoT Public key 0x0000_8000 KBOOT : Secure BootApplication mbed TLS 1) Always runs after chipcode reset and (Cryptography) checks defined interfaces (ie. USB) for 0x0000_FFFF host connection to get new firmware • Application code authentication is 0x0001_0000 applied before allowing application to run Your IoT • Protected by chip HW application mechanisms, can be made code immutable

0x0020_0000 0x0020_0000 Signature

PUBLIC 33 Overview of the Method

• Typical Application Development • Final production image

0x0000_0000 0x0000_0000 mbed TLS KBOOT Your IoT KBOOT 1) Used to hash the application code 0x0000_8000 Public key space then toApplication perform an ECDSA mbed TLS Verify using the signaturecode provided (Cryptography) by the firmware 0x0000_FFFF 0x0001_0000 Your IoT application code

0x0020_0000 0x0020_0000 Signature

PUBLIC 34 Overview of the Method

• Typical Application Development • Final production image

0x0000_0000 0x0000_0000 KBOOT Your IoT KBOOT Application Code Changes 0x0000_8000 Public key 1) Only use internalApplication flash after mbed TLS KBOOT (0xFFFF)code (Cryptography) 2) Add Boot Configuration area 0x0000_FFFF to hold information for the 0x0001_0000 bootloader Your IoT application code

0x0020_0000 0x0020_0000 Signature

PUBLIC 35 Using KBOOT for Signature Generation

Your Secure manufacturing facility

Factory App SREC SB Host PC with Host PC with K28F HW KBOOT tools KBOOT tools for KBOOT USB FS Factory Factory Elftosb Factory Application BD blhost PubKey SB bin Signature bin Elftosb blhost