If you develop firmware then you probably LOVE C and C++ so here are my guidelines for developing firmware for IoT devices that is “somewhat” resistant to hacking and vulnerabilities.
When developing firmware, I am always mindful of the potential vulnerabilities that can exist in the devices I design, particularly in the case of IoT devices that might be exposed to wireless security threats.
To help ensure the security and integrity of my firmware, I follow a number of guidelines and best practices.
- For example, I make sure to implement secure boot mechanisms to prevent attackers from flashing malicious firmware onto the device. This can include using code signing and verification to ensure that only trusted firmware images are executed and implementing measures to detect and prevent tampering with the boot process. For production, fuses are burned to prevent access to critical MCU functions.
- I also enable appropriate memory protection mechanisms to prevent unauthorized access to sensitive data stored in memory. This can include using memory protection units (MPUs) to set permissions on memory regions and implementing secure memory management techniques to prevent buffer overflows and other memory-related attacks.
- To protect against interception and modification of communication, I use secure communication channels such as encrypted USB or UART or turn them off completely in the production code.
- If the device supports over-the-air (OTA) updates, I make sure to implement a secure update process to prevent attackers from installing malicious firmware. This can include using code signing and verification to ensure the authenticity and integrity of the update, as well as implementing robust recovery mechanisms to handle any failures or errors during the update process.
- To secure the physical device and prevent attackers from gaining access to the hardware, I implement measures such as using tamper-resistant enclosures and implementing measures to detect and respond to physical tampering.
- In addition to these measures, I also follow best practices for coding and development in embedded systems. This can include using static code analysis tools to identify potential vulnerabilities and implementing measures to protect against common attacks such as stack smashing and heap overflow.
- I regularly perform security testing and assessments, such as code reviews, penetration testing, and vulnerability scanning, to identify and address any potential security issues.
By following these guidelines, I have had good results in developing secure code.