Securing IoT Devices with Tiny-AES-C and the APM32F003

The APM32F003 is a powerful microcontroller that is ideal for use in IoT devices due to its wide range of peripheral interfaces, and compact size. But APM32F003 does not have a built-in AES encryption and decryption module. This project use software to achieve AES encryption and decryption.

In this article, we will explore how to use the Tiny-AES-C library with the APM32F003 microcontroller to encrypt and decrypt data and to add an extra layer of security to your IoT device.APM32F003x4x6 series MCU is based on Arm® Cortex®-M0+ core, has a wide temperature range, high-precision and low-temperature bleaching. ESD is up to 8KV, with strong anti-interference ability; integrated high-speed internal oscillator, the complete range accuracy is within ± 3%, which can reach ± 1% after user calibration; support TSSOPD20, SOP20 and highly compact 3x3mm miniaturized package QFN20, which is conducive to improving system integration and reducing BOM material cost. At present, it has been successfully applied in wireless charging, motor control, electric toys, intelligent door locks and small household appliances, which are cost-sensitive and work in a relatively harsh environment.

It has a wide range of peripheral interfaces, including I2C, SPI, UART, and GPIO, making it a versatile chip that can be used in a variety of IoT devices.

Tiny-AES-C is an open-source software library that provides lightweight and efficient AES encryption for resource-constrained devices like the APM32F003. It supports key sizes of 128, 192, and 256 bits and can encrypt and decrypt data in ECB (Electronic Codebook), CBC (Cipher Block Chaining), CFB (Cipher Feedback mode), or OFB (Output Feedback mode).Let's look at a practical example of how to use the Tiny-AES-C library with the APM32F003 microcontroller to add security to an IoT device. In this example, we will use I2C protocol to transmit the encrypted data between two devices.

Include the following encryption and decryption tests in the code:

test_encrypt_cbc();
test_decrypt_cbc();
test_encrypt_ctr();
test_decrypt_ctr();
test_decrypt_ecb();
test_encrypt_ecb();
test_encrypt_ecb_verbose();

By utilizing the Tiny-AES-C library with the APM32F003 microcontroller, we can add an extra layer of security to our IoT devices, ensuring that the data we transmit is encrypted and protected from potential attacks. The wide range of peripheral interfaces of the APM32F003 make it an ideal choice for IoT devices, and the Tiny-AES-C library provides a lightweight and efficient way to add encryption to our projects.