Eyedecrypt—private interactions in plain sight

Abstract

We introduce EyeDecrypt, a novel technology for privacy-preserving human-computer interaction. EyeDecrypt allows only authorized users to decipher data shown on a display, such as an electronic screen or plain printed material; in the former case, the authorized user can then interact with the system (e.g., by pressing buttons on the screen), without revealing the details of the interaction to others who may be watching or to the system itself. The user views the decrypted data on a closely-held personal device, such as a pair of smart glasses with a camera and heads-up display, or a smartphone. The data is displayed as an image overlay on the personal device, which we assume cannot be viewed by the adversary. The overlay is a form of augmented reality that not only allows the user to view the protected data, but also to securely enter input into the system by randomizing the input interface. EyeDecrypt consists of three main components: a visualizable encryption scheme; a dataglyph-based visual encoding scheme for the ciphertexts generated by the encryption scheme; and a randomized input and augmented reality scheme that protects user inputs without harming usability. We describe all aspects of EyeDecrypt, from security definitions, constructions and analysis, to implementation details of a prototype developed on a smartphone.