Unmanned Aerial Vehicles (UAVs), commonly known as drones, are aircrafts without a human pilot aboard. The flight of drones can be controlled with a remote control by an operator located at the ground station, or fully autonomously by onboard computers. Drones are mostly found in the military. However, over the recent years, they have attracted the interest of industry and civilian sectors.
With the recent advance of sensor and embedded device technologies, various sensors will be embedded in city infrastructure to monitor various city-related information. In this context, drones can be effectively utilized in many safety-critical applications for collecting data from sensors on the ground and transmitting configuration instructions or task requests to these sensors.
However, drones, like many networked devices, are vulnerable to cyber and physical attacks.
Challenges for secure drone applications can be divided in four aspects: 1) securing communication between drones and sensors, 2) securing sensor localization when drones locate sensors, 3) providing secure drone platforms to protect sensitive data against physical capture attacks and detect modifications to drone software, and 4) protecting secret keys in drones under white-box attack environments.
To address the first challenge, a suite of cryptographic protocols is proposed. The protocols are based on certificateless cryptography and support authenticated key agreement, non-repudiation and user revocation. To minimize the energy required by a drone, a dual channel strategy is introduced.
To address the second challenge, a drone positioning strategy and a technique that can filter out malicious location references are proposed.
The third challenge is addressed by a solution integrating techniques for software-based attestation and data encryption.
For attestation, free memory spaces are filled with pseudo-random numbers, which are also utilized to encrypt data collected by the drone like a stream cipher.
A dynamic white-box encryption scheme is proposed to address the fourth challenge. Short secret key are converted into large look-up tables and the tables are periodically shuffled by a shuffling mechanism which is secure against white-box attackers.