Search

The success of new technologies depends on whether proper usage models can be found to support them. In this paper we present such a model for Intel's Software Guard Extensions (SGX) -- the leveraging of the technology to provide copy protection to software. We describe the system that we architected, designed and implemented, which transforms, in a fully automated manner, off-the-shelve applications into secured versions that run on top of the enclaves. Our system can be delivered as stand-alone, but also as a layer in existing software copy protection stacks.

During the last decade, social networks' free dissemination of personal information has reached a wide acceptance. Most of today's Internet users, especially teenagers, publish various kinds of sensitive information, without realizing that this information is preserved and might be detrimental to their future life and career. We present X-pire 2.0, which overcomes this unsatisfactory situation and puts users back in control of their published data. X-pire 2.0 is the first system that provides a digital expiration date and integrates robust protection against attackers creating digital copies of content before the expiration date has been reached. Our system leverages state-of-the-art trusted computing technologies and seamlessly integrates into the existing infrastructure on the Internet. X-pire 2.0 allows to add and enforce a digital expiration date on images that can be uploaded to existing social networks, since our enforcement is even robust against image recompression during upload. We implemented X-pire 2.0 for Android and show its practicality by publishing protected images in Google+ and Flickr.

Defining Digital Rights Management (DRM) is a complex task. There is no unique universal definition. There are many legal, economic, functional, and technical definitions. This complexity induces also that there is not one unique modeling of DRM. Each model should help to compare different DRM systems and easily highlight the differences and the similarities between them. One of the weaknesses of the current models is that none puts specifically the focus on the most important characteristics of DRM: protection of content and rights management. We propose a four-layer model that complements traditional ones. Using trust layer, rights management layer, rights enforcement layer, and content protection layer, this model is security oriented. It is suitable to describe any content protections such as DRM, conditional access, copy protection or even pre-recorded content protection systems.

The Advanced Access Content System (AACS) is the copy protection scheme for the new generation of high-definition DVD movies. Fundamentally,AACS is based on crypto-graphic principles. However, it has found a limited use for digital watermarking: first for playback control, and then, to a lesser extent,for forensics. This paper characterizes the forensic approach, and then describes AACS's "theatrical" and "consumer "watermarks and how they are used.

In this paper, we propose several methods to increase the difficulty of reverse engineering applications, with special emphasis on preventing the circumvention of copy protection mechanisms that permit only authorized users to execute the applications. We apply the hashing function to transform some constants in the software and recover them during the execution with the correct input of the password. The security of such a method depends on the hardness of the invertibility of the hashing function.

With the explosive growth of networked collections of musical material, there is a need to establish a mechanism like a digital library to manage music data. This paper presents a content-based processing paradigm of popular song collections to facilitate the realization of a music digital library. The paradigm is built on the automatic extraction of information of interest from music audio signals. Because the vocal part is often the heart of a popular song, we focus on developing techniques to exploit the solo vocal signals underlying an accompanied performance. This supports the necessary functions of a music digital library, namely, music data organization, music information retrieval/recommendation, and copyright protection.

The current landscape for digital rights management(DRM) consists of various ad hoc technologies and platforms that largely focus on copy protection. The fragmented nature of the DRM industry in 2004 is somewhat reminiscent of the telecommunications industry in the late 1980's. At that time various networking technologies were available, and what was needed was a technology that could integrate existing networks and provide various services to users. The OSI layered framework and the TCP/IP communications protocol suite provided a solution to this situation. The OSI model divides the process of digital data communications into layers. Likewise, in this paper we divide the process of DRM into layers in which various services are offered to the users of digital content at each layer. Three blocks of layers have been identified. The upper layers deal with the end-to-end functions of the application, the middle layers deal with rights expression and interpretation, and the lower layers ensure rights enforcement. This paper describes how responsibilities might be distributed among the various layers, and considers where in these layers it would be appropriate to define protocols and standards.

Recently, there is a growing interest in the research community to use tamper-resistant processors for software copy protection. Many of these tamper-resistant systems rely on a specially tailored secure processor to prevent, 1) illegal software duplication, 2) unauthorized software modification, and 3)unauthorized software reverse engineering. The published techniques primarily focused on feasibility demonstration and design details rather than analyzing security risks and potential attacks from an adversary's perspective. The uniqueness of software copy protection may lead to some potential attacks on such a secure environment that have been largely ignored or insufficiently addressed in the literature. One should not take security for granted just because it is implemented on a tamper-resistant secure processor. Detailed analysis on some proposed ideas reveal potential vulnerability and attacks. Some of the attacks are known to the security community, nevertheless, their implications to software copy protection are not well understood and discussed. This paper presents these cases for designers to improve their systems and circumvent the potential security pitfalls and for users of such systems to be aware of the potential risks

CSS, the first system to protect multimedia content on the new DVD medium failed badly, because both its encryption algorithm and its key management could easily be broken. A new industry initiative, the 4C Entity, LLC (founded by IBM, Intel, Matsushita and Toshiba), presents a more mature approach, called "Copy Protection for Prerecorded Media" (CPPM), which has already been adopted in DVD-Audio.A key-feature of CPPM is its advanced key-management, which allows for system renewability by revoking compromised devices. Renewability means that content provider can encrypt the content, such that compromised devices cannot decrypt it, whereas non-compromised devices still can.In this paper, we review the basic concepts of CPPM and propose a framework to study its cryptographic strengths based on the published specifications. We will focus our assessment especially on CPPM's key-management scheme, which, unfortunately, is not completely specified in the official publicly available specification. As a consequence, it is currently unknown, how the 4C Entity selects the device keys that are assigned to devices. As a main contribution we propose several suitable key-assignment strategies based on finite geometric structures and study their security.

Based on existing technology used in image and video watermarking, we have developed a robust audio watermarking technique. The embedding algorithm operates in frequency domain, where the magnitudes of the Fourier coefficients are slightly modified. In the temporal domain, an additional scale parameter and gain function are necessary to refine the watermark and achieve perceptual transparency. Watermark detection relies on the Symmetrical Phase Only Matched Filtering (SPOMF) cross-correlation approach. Not only the presence of a watermark, but also its cyclic shift is detected. This shift supports a multi-bit payload for one particular watermark sequence. The watermarking technology proved to be very robust to a large number of signal processing “attacks” such as MP3 (64 kb/s), all-pass filtering, echo addition, time-scale modification, resampling, noise addition, etc. It is expected that this approach may contribute in a wide variety of existing (e.g. monitoring and copy protection) and future applications.

A number of researchers have proposed using digital marks to provide ownership identification for intellectual property. Many of these techniques share three specific weaknesses: complexity of copy detection, vulnerability to mark removal after revelation for ownership verification, and mark integrity issues due to partial mark removal. This paper presents a method for watermarking field programmable gate array (FPGA) intellectual property (IP) that achieves robustness by responding to these three weaknesses. The key technique involves using secure hash functions to generate and embed multiple small marks that are more detectable, verifiable, and secure than existing IP protection techniques.