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Eindhoven University of Technology MASTER a Diskless Cluster Eindhoven University of Technology MASTER A diskless cluster architecture for hashing operations Antakis, S. Award date: 2010 Link to publication Disclaimer This document contains a student thesis (bachelor's or master's), as authored by a student at Eindhoven University of Technology. Student theses are made available in the TU/e repository upon obtaining the required degree. The grade received is not published on the document as presented in the repository. The required complexity or quality of research of student theses may vary by program, and the required minimum study period may vary in duration. General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain Technische Universiteit of Eindhoven Department of Computer Science & Mathematics A Diskless Cluster Architecture for Hashing Operations by Spyridon Antakis Supervisor Benne de Weger Mentor Padraic Garvey Intel Shannon, Ireland August 2010 Acknowledgements Passion comes within the mind. It is a state of mind which purely define us. It is an unavoidable consequence of our weak nature. There are no definitions or confinements and there should not be. Each individual is a part of a project called "world". The mission is to accomplish personal balance between of a life that comes with choices. Anything else, just belongs to the process. We are carved from our experiences and we are judged from our actions. Shameless and proud for what we are, we should continue. At the moment on which we reach our mental complete- ness, we know that we arrived to our final destination. I do not need from you to understand, I do not need from you to believe, I just need to accept and proceed. The truth always lies at different levels, mine is inside my passions. Expectations arise and set, I just need to fulfill them. Seizing every single moment of life finally brings me to the ultimate conclusion, "life is too short to have them all", but still is a great walk that I should enjoy. After all, it is the only way to really know myself. As each journey comes to an end, a circle closes and harmony persists. Through a long-run which was meant to shape me, I am rewarded. And now I know, here I stand to pay my respects to my inspirers. Thank you, for being all along. Spyridon Antakis Preface The current document constitutes an attempt to investigate the behavior of a cluster based architecture with respect to the performance of several open source hashing implementations. Hashing algorithms find applicability in a majority of cryptographic operations and thus, such a research effort obtains a significant value. By considering also the fact that most of the benchmarked hashing implementations are included in all standard Linux Distributions, the presented results have an even more broad meaning. More precisely, by building a diskless cluster a number of well- known hashing tools are successfully tested, under a variety of different hardware. An interesting aspect of the entire experiment is the inclusion of a new hashing prototype, called Skein. This algorithm was developed from a group of security experts and at the moment, it has been qualified to the pre-final round of NIST Hashing Competition. At the end of 2010, this competition will define the final competitors for the standardization of SHA-3. Skein is believed to be one of the promising candidates for winning the competition and since its authors reported that is faster from SHA-2, it was considered tempting to be benchmarked and compared to the existing hashing algorithms. However, the benchmarking of this hybrid proposal was based on one of the few available implementations, which is written as a python library. Therefore, there are no significant comparative references and only the sample performance reports that Skein's authors published, represent a possible metric. The initial inspiration for our research was derived from several different security aspects, but its main root lies on an existing vulnerability of the Wi-Fi Protected Access (WPA) protocol. The Pre-Shared Key (PSK) mode of this protocol is known to be vulnerable against off-line dictionary attacks, nevertheless the intensive hashing computations for performing the attack require an enormous processing power. As it was described in previous WPA-PSK cryptanalysis attempts, the concept of pre-computed hashing could be used for optimizing the attack. In practice, there is a vital need for powerful processing capabilities, since only then you could end up with desired results inside a feasible time frame. The technique of hashing pre-computations is not something new and an entire methodology for generating pre-computed lookup tables exists for several years now, mostly known as rainbow tables. This technique is still able to spare us computational time and decrease the processing workload, especially when salting is omitted. Motivated purely by the idea of exploiting the scalability of hashing operations, the vision of building a diskless cluster architecture became an interesting task. Even though this document does not conduct experiments with the latest available hardware, it will become obvious during the review of the content that this does not oppose any limita- tions for using cutting edge processing hardware. The capabilities of the diskless cluster architecture are based on the resources that cluster includes and the restrictions that these resources induce. Thus, there are no specific hardware requirements and nothing stops an architect to transform this basic architecture to a dedicated crypto-cluster. As it will be briefly discussed in one of the chapters, todays emerging technology for cryptography focuses on developing embedded mechanisms inside the new generations of processors, that will be able to deliver cryptographic acceler- ation at amazingly high-rates. A combination of the described diskless cluster architecture with such accelerators, it is strongly believed that could provide an extremely powerful dedicated structure for cryptographic operations. Unfortunately, for reasons that we will briefly discuss under the content of this document, these experiments were not performed and were left as a potential future work. Nevertheless, all the needed details are included and the conclusions for the benefits for such a combination, it is believed that would be feasible to be extracted from the content of this research. The several sections of this dissertation try to give an in depth insight on the different involved issues, which arise from the proposed architecture. Even if it is almost impossible to exhaust all the existing aspects, our efforts focus on presenting all the details and information that could have a significant value for the research community. The perception of the author with respect to the revealed drawbacks and advantages is discussed and a concrete evaluation on the benchmarked hashing algorithms (e.g. MD5, SHA-1, SHA-2, Tiger, Whirlpool, Skein) is performed. Two basic test cases are applied and through a statistical analysis the reader is able to comprehend and highlight all the interesting points, by comparing also the variations of hashing algorithms. At this point it should be mentioned, that this document does not aim to provide extended details on the theoretical nature of hashing algorithms and only a sufficient necessary background is provided. Moreover, it does not attempt to apply any brute force attacks on the existing WPA-PSK vulnerability and the case study on WPA-PSK is presented only as an example for the usability that this architecture could have on the field of cryptanalysis. The main objective is to identify and investigate the behavior of the hashing algorithms on the cluster-based architecture. The focus remains strictly on the processing of the computational workload and the general behavior of the cluster architecture. The high-end goal is to inspire additional research on the field of clustering for cryptography and answer a number of research questions with respect to the proposed model. Contents Contents Acknowledgements .................................................. 3 Preface .......................................................... 5 List of Figures ..................................................... 9 1 Hashing on a Diskless Cluster ......................................... 11 1.1 Hash Function Design Principles . 12 1.1.1 Definitions & Security Properties . 12 1.1.2 Generic Attacks . 13 1.2 Hashing Algorithms . 13 1.2.1 MD5: Message Digest Algorithm 5 . 14 1.2.2 SHA-1: Secure Hash Algorithm 1 . 14 1.2.3 SHA-2: Secure Hash Algorithm 2 . 14 1.2.4 Whirlpool . 15 1.2.5 Tiger . 15 1.3 NIST Competition . 15 1.3.1 Skein . 15 2 Areas of Applicability .............................................. 17 2.1 Security Protocols . 17 2.2 Digital Forensics . 18 2.3 Cryptanalysis Tools . 19 2.4 A Case Study for Wi-Fi Protected Access (WPA) . 20 2.4.1 The Key Hierarchy . 20 2.4.2 The 4-Way Handshake . 21 2.4.3 Performing the Attack . 22 2.4.4 Previous Experiments . 22 3 On the way of Benchmarking .......................................... 24 3.1 General Concept . 24 3.2 The Puzzle of Hardware . 25 3.3 Database . 28 3.4 Open Source Hashing Implementations . 28 3.5 Shell Scripts . 29 3.6 Research Questions . 30 4 Building a Scalable Cluster ........................................... 33 4.1 The Diskless Architecture . 33 4.2 Clustering Tools . 34 4.2.1 Diskless Remote Boot in Linux (DRBL) . 34 4.2.2 TORQUE & Maui . 36 4.3 Job Scheduling & Scripts . 37 5 Hardware Acceleration for Cryptography .................................. 39 5.1 Intel EP80579 Processor .
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