IOT is developing more and more rapidly, and the deployed link devices are growing explosively. Many of the devices in the Internet of Things are small devices such as sensors and gateways. IoT devices are not as powerful as PCs and other devices, but the large number of them is still very attractive to hackers. In the past year, many large-scale IOT-based DDOS attacks have occurred, which has attracted widespread attention and some security defense measures have been taken one after another.
The most basic chips of the Internet of Things are the Arm architecture. As of now, the arm ecosystem partners have shipped more than 100 billion arm-based chips, and it is expected that 100 billion arm-based chips will be shipped from now until 2021. ARMs are everywhere in the Internet of Things field. How can we protect our security from the underlying chips? Paul Williamson, vice president of
arm and general manager of the Internet of Things Device IP Business Group, said: "For the entire industrial value chain from the end to the cloud, security should not be an after-reparation measure. By 2021, the cumulative shipment of the arm-based chips in the arm ecosystem will reach 200 billion. 200 billion is an amazing number, which also means that the heavy responsibility of the arm and the arm ecosystem to jointly ensure that the increasingly diversified interconnected devices can be based on a common security foundation." To this end, arm announced the launch of the first industry-wide framework - Platform Security Architecture (PSA) to create secure IoT devices from the underlying chip level.
IOT network involves many parts such as chips, devices, networks, applications, and clouds. Security issues must be paid attention to in every link. Many well-known device manufacturers, application manufacturers, system manufacturers, cloud service providers, etc. have announced the basic principles of PSA, which supports ARM's platform security architecture.
PSA platform security architecture is a whole composed of threat model, security analysis, and hardware and firmware architecture specifications. PSA provides a framework based on industry best practices through which consistent security design can be achieved at the hardware and firmware level. This architecture provides a common rule for device manufacturers to reduce development costs, time and risks when dealing with IoT security issues. In addition, Arm also launched an open source (source code is expected to be released in early 2018) reference implementation for Armv8-M-based devices. The components of PSA are constructed according to three aspects: analysis, architecture and implementation.
analysis fully understands risks and threat factors, starts from a series of threat models and security analysis, and considers a variety of IoT use cases in combination with assets and potential threats. The model analysis contained in PSA can be used as examples and guiding principles to solve similar problems encountered in other cases. This method is based on the formal safety certification process commonly used in the industry.
architecture creates architecture specifications for firmware and hardware, covering core security principles identified through security analysis, and providing consistent functions and interfaces. These common principles include device identity, trusted startup, secure OTA software updates, and certificate-based authentication.
implementation Arm provides a variety of security technologies and chip IPs to help designers build more secure systems. The open-source Trusted Firmware-M will serve as the industry's entry point on the software side, providing reference implementation for PSA.
Arm proposes a 4-step model for IoT-related standards. First, the identity of the device must be unique; second, a trusted known startup program; third, if any potential problems occur, a software upgrade must be implemented; fourth, certificate-based authentication, that is, ensure that the device that communicates with you is indeed trustworthy, rather than fake devices.
PSA is not restricted by the operating system and is able to obtain support from all Arm RTOS and its software vendor partners, including the latest version of Mbed OS that has been recognized by the market. In addition, Arm has launched new members of the security IP product family: Arm TrustZone CryptoIsland and Arm CoreSight SDC-600. Among them, Arm TrustZone CryptoIsland – it is a new series of highly integrated security subsystems designed to achieve on-chip smart card level security.The first generation of the product, CryptoIsland-300, is aimed at applications that require high isolation and security, such as LPWA, storage and automobiles. The Arm CoreSight SDC-600 secure debugging channel can support complete debugging functions without sacrificing system security, and integrates a dedicated verification mechanism for debugging access, making it easier for the device to debug during its life cycle.
PSA is an economical, upgradeable, scalable and easy to implement security framework created by Arm. It is unquestionable to use PSA to be more secure than before, but it is not absolutely safe. For example, Arm's security IP Arm CoreSight SDC-600 can support a secure debugging channel. Is this secure debugging channel necessarily safe? I'm afraid it may not be, but as long as the value of cracking far exceeds the benefits obtained by cracking it, it will be safe in most cases.
