Survey on Camera Based Communication for Location-Aware Secure Authentication and Communication
Total Page：16
File Type：pdf, Size：1020Kb
Survey on Camera based Communication for Location-Aware Secure Authentication and Communication Hannes Plank∗, Christian Stegery, Thomas Ruprechter∗, Gerald Holweg∗, Norbert Druml∗ ∗Infineon Technologies Austria AG, Graz, Austria yInstitute for Technical Informatics, Graz University of Technology, Austria fhannes.plank, thomas.ruprechter, gerald.holweg, norbert.drumlg@infineon.com, [email protected] Abstract—Contactless communication and authentication in without the owner’s presence. Francillon et al. [1] successfully the RF-domain is still impaired from relay attacks. Countermea- executed this attack on 10 different car models and were able sures like distance bounding protocols are difficult to implement to gain entry and to start the engine. Distance bounding pro- properly and are still continuously broken by sophisticated attacks. This work reviews a variety of approaches to counter- tocols can limit the maximum allowed distance between two act relay attacks by adding location-awareness to the security communication partners, but have been successfully attacked. concept. Camera based optical line of sight communication is If both communication partners can determine their relative an alternative to RF communication and provides location- position in a reliable way, the vulnerability against relay- awareness by the ability of sensing communication partners. attacks might improve [2]. Concepts and methods of this field are introduced and their contribution to location-aware security analyzed. This work discusses security aspects of location-awareness Finally, we present OptiSec3D, which is our novel approach with a focus on camera based communication systems. Camera to use Time-of-Flight 3D cameras for secure communication. based communication systems can have the ability to sense Our proposed system combines state-of-the-art cryptographic their communication partner, and visually detect attackers. security with 3D depth recognition and camera based optical However, most approaches have a limited range and just communication. Various attack scenarios are identified and discussed. We show how our system can improve the security rely on the optical channel for security. We introduce our of previous camera-based communication systems and how it OptiSec3D approach, which overcomes the boundaries of can drastically reduce the risk of relay attacks. other camera based communication systems by using Time- Keywords—Time-of-Flight, contactless authentication, camera of-Flight 3D cameras. Our security concept relies on state- based communication, security, 3D sensing of-the-art hardware-accelerated cryptography in combination with Time-of-Flight 3D sensing and its optical communication I. INTRODUCTION ability. The demand for secure contactless authentication and com- munication methods is growing steadily. Applications range II. TIME-OF-FLIGHT 3D SENSING from mobile payment, access control, device pairing, elec- Time-of-Flight is a sensing technology that provides dis- tronic passports to keyless car entry and start systems. In tance information by measuring the travel time of emitted these applications, the devices face the challenge to establish light. There are two fundamental Time-of-Flight principles, the a secure connection over an insecure channel. While cryp- direct and the indirect measurement approaches. The indirect tographic methods, like Diffie-Hellman key exchange, digital method, which is illustrated in Fig. 2, measures distance signatures and message authentication can be combined to a information by analyzing the phase shift between the emitted secure protocol, the risk of relay attacks persists. modulated infrared light and the reflected light with the help of An example of a relay attack on a keyless car entry system is illustrated in Fig. 1. An attacker relays the communication between an entry token to the car. Access can be gained LED / Laser Illumination Optical Signal Electrical Signal Modulation 3D Block Scene Time-of-Flight Sensor Electrical Signal Depth Relflected Post Data Optical Signal Phase Shift Raw Processing Amplitude Data Data Reflected Electrical Signal Fig. 2. The concept of PMD-based Time-of-Flight 3D sensing, obtained with Fig. 1. Concept of a relay attack on passive keyless car entry systems changes from [3]. photonic mixing devices (PMD), as explained by the authors not designed for localization. The main motivation for Wifi in [4]. localization is not security, but indoor navigation and location Thanks to this concept (monocular, no baseline required, lit- based services. tle power consumption), PMD-based Time-of-Flight cameras Wifi fingerprinting is a well-established technique, offering can be easily miniaturized and integrated into small embedded coarse localization. It requires a time-consuming calibration devices in a very robust way. The raw data, which is gathered of the signal strength indicator (RSSI) in the network [19]. by the sensor, is then post processed by a processing pipeline. Because of the Wifi signal characteristics, the RSSI depends The outcome of this pipeline is 3D depth information of the on the location. The problem with Wifi fingerprinting is that scenery and amplitude information, which can be used as a it requires an RSSI map of the Wifi access point and is robust infrared image. Given these features, future Time-of- thus volatile to environmental changes. SecureAngle [20] is a Flight camera systems will enable the concept of ubiquitous system to overcome fingerprinting based techniques by using real-time geometry devices that provide 3D data for our multi-antenna access points to create unique angle signatures everyday applications. of the clients. There are approaches to enrich Wifi-based localization with additional signals, cf. Niu et al. with Zigbee III. LOCATION-AWARENESS IN THE RF-DOMAIN [21]. Tippenhauer et al. [22] show that Wifi-based localization This section reviews approaches aiming to tackle the re- can be spoofed by replaying localization signals. There are maining problems of secure communication over an insecure countermeasures possible but according to Tippenhauer, Wifi- channel by introducing distance or location-awareness. Relay based localization cannot be reliably used in security applica- attacks, also named mafia fraud attacks, prove to be sever and tions. difficult to avoid. As listed by Fischlin et al. [5], relay attacks A different paradigm for localization is sound positioning have been successfully implemented on applications such as [23]. According to Clulow [16], sound positioning offers pre- Bluetooth [6], [7], smartcards [8], [9], [10], [11], electronic cise localization due to the slower propagation speed of sound. passports [12], voting systems [13] and passive keyless car Sound-based security mechanisms are however vulnerable to entry systems [1]. relay attacks because the communication can be relayed over Distance bounding protocols [14] are the most common a faster medium. protection against relay attacks. The core concept is to intro- Visible light communication (VLC) has recently gained mo- duce an upper bound on the distance between communication mentum through the rise of the Internet of Things (IoT). The partners. This bound is usually enforced by timing the delay security aspects of visible light communications are discussed between a sent message the reply of the partner. This limited by Rohner et al. [24] in their survey. Physical security features reply time hampers an attacker to rely the message to a third of the visible light channel were introduced by Mostafa et al. party which is not within this boundary. in [25] and [26]. They use null-steering, artificial noise and Brelurut et al. [15] provide a recent survey about distance beamforming to mitigate eavesdropping. bounding protocols. According to Clulow et al. [16], some hardware is not fit to handle the tight timing constraints of IV. CAMERA-BASED COMMUNICATION distance bounding. Sometimes, the clocks are not precise There are several approaches to use cameras for optical enough to reliably employ distance bounding. The protocols communication. The obvious benefit for secure communica- are often just implemented in software layers, which also tion is that due to the optical line-of-sight communication doesn’t allow strict distance bounding. This is due the fact principle, an attacker needs to be within the field of view that the time a message travels through the air is very low of the cameras. This section provides an overlook on camera compared to the response time of an electronic device. An communication principles. Security aspects of camera com- attacker can be faster at relaying messages, spoofing the munication are reviewed in Section V. original distance. There are approaches, like Clulow et al. Analyzing image data can lead to recognition of the com- outlined in [16], to avoid this by using probabilistic models munication partner and validation of its location. The limited about timing behavior to detect attackers. Despite the past frame-rate of common image sensors is compensated by the research effort, which resulted in over 40 distance bounding high numbers of pixels. This guarantees enough bandwidth protocols, they still show vulnerability against attacks [16], for a lot of applications. The most common way to use [17]. Cremers et al. [17] proposed distance hijacking attacks, 2D cameras for communication is using displays to stream where the attacker uses unsuspecting third parties to verify the 2D barcodes. This principle is known as pixelated multiple distance measurement.