A Survey on Lightweight Entity Authentication with Strong PUFs
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paper_title: Cloning Physically Unclonable Functions

paper_content:

As system security demands continue to evolve, Physically Unclonable Functions (PUFs) are a promising solution for secure storage on Integrated Circuits (ICs). SRAM PUFs are among the most popular types of PUFs, since they require no additional circuitry and can be implemented with on-die memories such as caches and data memory that are readily available on both ASICs and FPGAs. This work demonstrates that SRAM PUFs are not well suited as PUFs, as they do not meet several requirements that constitute an ideal PUF. The compact nature of SRAM, standard interconnects and resiliency to environmental effects make SRAM PUFs particularly easy to clone. We consider several ways in which SRAM PUFs can be characterized and demonstrate a Focused Ion Beam circuit edit with which we were able to produce a physical clone of our Proof-of-Concept SRAM PUF implementation. As a result of the circuit edit, when challenged, the physical clone produced an identical physical response to the original device. To the best of our knowledge, this is the first work in which a physical clone of a Physically Unclonable Function was produced.
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paper_title: A technique to build a secret key in integrated circuits for identification and authentication applications

paper_content:

This paper describes a technique that exploits the statistical delay variations of wires and transistors across ICs to build a secret key unique to each IC. To explore its feasibility, we fabricated a candidate circuit to generate a response based on its delay characteristics. We show that there exists enough delay variation across ICs implementing, the proposed circuit to identify individual ICs. Further. the circuit, functions reliably over a practical range of environmental variation such as temperature and voltage.
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paper_title: Efficient Power and Timing Side Channels for Physical Unclonable Functions

paper_content:

One part of the original PUF promise was their improved resilience against physical attack methods, such as cloning, invasive techniques, and arguably also side channels. In recent years, however, a number of effective physical attacks on PUFs have been developed [17,18,20,8,2]. This paper continues this line of research, and introduces the first power and timing side channels SCs on PUFs, more specifically on Arbiter PUF variants. Concretely, we attack so-called XOR Arbiter PUFs and Lightweight PUFs, which prior to our work were considered the most secure members of the Arbiter PUF family [28,30]. We show that both architectures can be tackled with polynomial complexity by a combined SC and machine learning approach. ::: ::: Our strategy is demonstrated in silicon on FPGAs, where we attack the above two architectures for up to 16 XORs and 512 bits. For comparison, in earlier works XOR-based Arbiter PUF designs with only up to 5 or 6 XORs and 64 or 128 bits had been tackled successfully. Designs with 8 XORs and 512 bits had been explicitly recommended as secure for practical use [28,30]. ::: ::: Together with recent modeling attacks [28,30], our work shows that unless suitable design countermeasures are put in place, no remaining member of the Arbiter PUF family resists all currently known attacks. Our work thus motivates research on countermeasures in Arbiter PUFs, or on the development of entirely new Strong PUF designs with improved resilience.
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paper_title: Physical Characterization of Arbiter PUFs

paper_content:

As intended by its name, Physically Unclonable Functions PUFs are considered as an ultimate solution to deal with insecure storage, hardware counterfeiting, and many other security problems. However, many different successful attacks have already revealed vulnerabilities of certain digital intrinsic PUFs. Although settling-state-based PUFs, such as SRAM PUFs, can be physically cloned by semi-invasive and fully-invasive attacks, successful attacks on timing-based PUFs were so far limited to modeling attacks. Such modeling requires a large subset of challenge-response-pairs CRP to successfully model the targeted PUF. In order to provide a final security answer, this paper proves that all arbiter-based i.e. controlled and XOR-enhanced PUFs can be completely and linearly characterized by means of photonic emission analysis. Our experimental setup is capable of measuring every PUF-internal delay with a resolution of 6 picoseconds. Due to this resolution we indeed require only the theoretical minimum number of linear independent equations i.e. physical measurements to directly solve the underlying inhomogeneous linear system. Moreover, we neither require to know the actual PUF challenges nor the corresponding PUF responses for our physical delay extraction. On top of that devastating result, we are also able to further simplify our setup for easier physical measurement handling. We present our practical results for a real arbiter PUF implementation on a Complex Programmable Logic Device CPLD from Altera manufactured in a 180 nanometer process.
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paper_title: Physical unclonable functions for device authentication and secret key generation

paper_content:

Physical Unclonable Functions (PUFs) are innovative circuit primitives that extract secrets from physical characteristics of integrated circuits (ICs). We present PUF designs that exploit inherent delay characteristics of wires and transistors that differ from chip to chip, and describe how PUFs can enable low-cost authentication of individual ICs and generate volatile secret keys for cryptographic operations.
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paper_title: PUF Modeling Attacks on Simulated and Silicon Data

paper_content:

We discuss numerical modeling attacks on several proposed strong physical unclonable functions (PUFs). Given a set of challenge-response pairs (CRPs) of a Strong PUF, the goal of our attacks is to construct a computer algorithm which behaves indistinguishably from the original PUF on almost all CRPs. If successful, this algorithm can subsequently impersonate the Strong PUF, and can be cloned and distributed arbitrarily. It breaks the security of any applications that rest on the Strong PUF's unpredictability and physical unclonability. Our method is less relevant for other PUF types such as Weak PUFs. The Strong PUFs that we could attack successfully include standard Arbiter PUFs of essentially arbitrary sizes, and XOR Arbiter PUFs, Lightweight Secure PUFs, and Feed-Forward Arbiter PUFs up to certain sizes and complexities. We also investigate the hardness of certain Ring Oscillator PUF architectures in typical Strong PUF applications. Our attacks are based upon various machine learning techniques, including a specially tailored variant of logistic regression and evolution strategies. Our results are mostly obtained on CRPs from numerical simulations that use established digital models of the respective PUFs. For a subset of the considered PUFs-namely standard Arbiter PUFs and XOR Arbiter PUFs-we also lead proofs of concept on silicon data from both FPGAs and ASICs. Over four million silicon CRPs are used in this process. The performance on silicon CRPs is very close to simulated CRPs, confirming a conjecture from earlier versions of this work. Our findings lead to new design requirements for secure electrical Strong PUFs, and will be useful to PUF designers and attackers alike.
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paper_title: Fuzzy Extractors: How to Generate Strong Keys from Biometrics and Other Noisy Data

paper_content:

We provide formal definitions and efficient secure techniques for - turning biometric information into keys usable for any cryptographic application, and - reliably and securely authenticating biometric data. Our techniques apply not just to biometric information, but to any keying material that, unlike traditional cryptographic keys, is (1) not reproducible precisely and (2) not distributed uniformly. We propose two primitives: a fuzzy extractor extracts nearly uniform randomness R from its biometric input; the extraction is error-tolerant in the sense that R will be the same even if the input changes, as long as it remains reasonably close to the original. Thus, R can be used as a key in any cryptographic application. A secure sketch produces public information about its biometric input w that does not reveal w, and yet allows exact recovery of w given another value that is close to w. Thus, it can be used to reliably reproduce error-prone biometric inputs without incurring the security risk inherent in storing them. In addition to formally introducing our new primitives, we provide nearly optimal constructions of both primitives for various measures of closeness of input data, such as Hamming distance, edit distance, and set difference.
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paper_title: Power-Up SRAM State as an Identifying Fingerprint and Source of True Random Numbers

paper_content:

Intermittently powered applications create a need for low-cost security and privacy in potentially hostile environments, supported by primitives including identification and random number generation. Our measurements show that power-up of SRAM produces a physical fingerprint. We propose a system of fingerprint extraction and random numbers in SRAM (FERNS) that harvests static identity and randomness from existing volatile CMOS memory without requiring any dedicated circuitry. The identity results from manufacture-time physically random device threshold voltage mismatch, and the random numbers result from runtime physically random noise. We use experimental data from high-performance SRAM chips and the embedded SRAM of the WISP UHF RFID tag to validate the principles behind FERNS. For the SRAM chip, we demonstrate that 8-byte fingerprints can uniquely identify circuits among a population of 5,120 instances and extrapolate that 24-byte fingerprints would uniquely identify all instances ever produced. Using a smaller population, we demonstrate similar identifying ability from the embedded SRAM. In addition to identification, we show that SRAM fingerprints capture noise, enabling true random number generation. We demonstrate that a 512-byte SRAM fingerprint contains sufficient entropy to generate 128-bit true random numbers and that the generated numbers pass the NIST tests for runs, approximate entropy, and block frequency.
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paper_title: FPGA Intrinsic PUFs and Their Use for IP Protection

paper_content:

In recent years, IP protection of FPGA hardware designs has become a requirement for many IP vendors. In [34], Simpson and Schaumont proposed a fundamentally different approach to IP protection on FPGAs based on the use of Physical Unclonable Functions (PUFs). Their work only assumes the existence of a PUF on the FPGAs without actually proposing a PUF construction. In this paper, we propose new protocols for the IP protection problem on FPGAs and provide the first construction of a PUF intrinsic to current FPGAs based on SRAM memory randomness present on current FPGAs. We analyze SRAM-based PUF statistical properties and investigate the trade offs that can be made when implementing a fuzzy extractor.
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paper_title: Reverse Fuzzy Extractors: Enabling Lightweight Mutual Authentication for PUF-Enabled RFIDs

paper_content:

RFID-based tokens are increasingly used in electronic payment and ticketing systems for mutual authentication of tickets and terminals. These systems typically use cost-effective tokens without expensive hardware protection mechanisms and are exposed to hardware attacks that copy and maliciously modify tokens. Physically Unclonable Functions (PUFs) are a promising technology to protect against such attacks by binding security critical data to the physical characteristics of the underlying hardware. However, existing PUF-based authentication schemes for RFID do not support mutual authentication, are often vulnerable to emulation and denial-of service attacks, and allow only for a limited number of authentications.
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paper_title: Secure remote authentication using biometric data

paper_content:

Biometric data offer a potential source of high-entropy, secret information that can be used in cryptographic protocols provided two issues are addressed: (1) biometric data are not uniformly distributed; and (2) they are not exactly reproducible. Recent work, most notably that of Dodis, Reyzin, and Smith, has shown how these obstacles may be overcome by allowing some auxiliary public information to be reliably sent from a server to the human user. Subsequent work of Boyen has shown how to extend these techniques, in the random oracle model, to enable unidirectional authentication from the user to the server without the assumption of a reliable communication channel. We show two efficient techniques enabling the use of biometric data to achieve mutual authentication or authenticated key exchange over a completely insecure (i.e., adversarially controlled) channel. In addition to achieving stronger security guarantees than the work of Boyen, we improve upon his solution in a number of other respects: we tolerate a broader class of errors and, in one case, improve upon the parameters of his solution and give a proof of security in the standard model.
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paper_title: Fuzzy Extractors: How to Generate Strong Keys from Biometrics and Other Noisy Data

paper_content:

We provide formal definitions and efficient secure techniques for - turning biometric information into keys usable for any cryptographic application, and - reliably and securely authenticating biometric data. Our techniques apply not just to biometric information, but to any keying material that, unlike traditional cryptographic keys, is (1) not reproducible precisely and (2) not distributed uniformly. We propose two primitives: a fuzzy extractor extracts nearly uniform randomness R from its biometric input; the extraction is error-tolerant in the sense that R will be the same even if the input changes, as long as it remains reasonably close to the original. Thus, R can be used as a key in any cryptographic application. A secure sketch produces public information about its biometric input w that does not reveal w, and yet allows exact recovery of w given another value that is close to w. Thus, it can be used to reliably reproduce error-prone biometric inputs without incurring the security risk inherent in storing them. In addition to formally introducing our new primitives, we provide nearly optimal constructions of both primitives for various measures of closeness of input data, such as Hamming distance, edit distance, and set difference.
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paper_title: Side-channel analysis of PUFs and fuzzy extractors

paper_content:

Embedded security systems based on Physical Unclonable Functions (PUFs) offer interesting protection properties, such as tamper resistance and unclonability. However, to establish PUFs as a high security primitive in the long run, their vulnerability to side-channel attacks has to be investigated. For this purpose, we analysed the side-channel leakage of PUF architectures and fuzzy extractor implementations. We identified several attack vectors within common PUF constructions and introduce two side-channel attacks on fuzzy extractors. Our proof-of-concept attack on an FPGA implementation of a fuzzy extractor shows that it is possible to extract the cryptographic key derived from a PUF by side-channel analysis.
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paper_title: Fuzzy Extractors: How to Generate Strong Keys from Biometrics and Other Noisy Data

paper_content:

We provide formal definitions and efficient secure techniques for ::: ::: ::: turning biometric information into keys usable for any cryptographic application, and ::: ::: ::: reliably and securely authenticating biometric data.
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paper_title: Helper Data Algorithms for PUF-Based Key Generation: Overview and Analysis

paper_content:

Security-critical products rely on the secrecy and integrity of their cryptographic keys. This is challenging for low-cost resource-constrained embedded devices, with an attacker having physical access to the integrated circuit (IC). Physically, unclonable functions are an emerging technology in this market. They extract bits from unavoidable IC manufacturing variations, remarkably analogous to unique human fingerprints. However, post-processing by helper data algorithms (HDAs) is indispensable to meet the stringent key requirements: reproducibility, high-entropy, and control. The novelty of this paper is threefold. We are the first to provide an in-depth and comprehensive literature overview on HDAs. Second, our analysis does expose new threats regarding helper data leakage and manipulation. Third, we identify several hiatuses/open problems in existing literature.
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paper_title: Differential template attacks on PUF enabled cryptographic devices

paper_content:

In this paper we provide the first practical attacks on software implementations of fuzzy extractors (FEs). The significance of these attacks stem from the fact that FEs are becoming an essential building block in the implementations of physical unclonable function (PUF) enabled devices. In fact, almost every single implementation of PUFs heavily relies on using a FE. Our attacks exploit the information leaked through the power side-channel in the initial stages of error correction and can be used to recover the FE input which would essentially mean cloning the PUF device. More specifically, our attacks target the initial step in the syndrome decoding phase of BCH and Reed-Solomon (RS) decoder implementations where the input (PUF response) is read. We report two attacks: a simple power analysis (SPA) attack where we make use of conditional checks in a naive implementation to recover the PUF response by simply observing time shifts in the power consumption profile. In our second attack, we assume all conditional executions are removed making the device secure against SPA attacks. Instead, we mount a new kind of template attack on a two instruction sequence to recover the FE input (or PUF output).
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paper_title: An Accurate Probabilistic Reliability Model for Silicon PUFs

paper_content:

The power of an accurate model for describing a physical process or designing a physical system is beyond doubt. The currently used reliability model for physically unclonable functions (PUFs) assumes an equally likely error for every evaluation of every PUF response bit. This limits an accurate description since experiments show that certain responses are more error-prone than others, but this fixed error rate model only captures average case behavior. We introduce a new PUF reliability model taking this observed heterogeneous nature of PUF cells into account. An extensive experimental validation demonstrates the new predicted distributions describe the empirically observed data statistics almost perfectly, even considering sensitivity to operational temperature. This allows studying PUF reliability behavior in full detail, including average and worst case probabilities, and is an invaluable tool for designing more efficient and better adapted PUFs and PUF-based systems.
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paper_title: A technique to build a secret key in integrated circuits for identification and authentication applications

paper_content:

This paper describes a technique that exploits the statistical delay variations of wires and transistors across ICs to build a secret key unique to each IC. To explore its feasibility, we fabricated a candidate circuit to generate a response based on its delay characteristics. We show that there exists enough delay variation across ICs implementing, the proposed circuit to identify individual ICs. Further. the circuit, functions reliably over a practical range of environmental variation such as temperature and voltage.
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paper_title: Testing Techniques for Hardware Security

paper_content:

System security has emerged as a premier design requirement. While there has been an enormous body of impressive work on testing integrated circuits (ICs) desiderata such as manufacturing correctness, delay, and power, there is no reported effort to systematically test IC security in hardware. Our goal is to provide an impetus for this line of research and development by introducing techniques and methodology for rigorous testing of physically unclonable functions (PUFs). Recently, PUFs received a great deal of attention as security mechanisms due to their flexibility to form numerous security protocols and intrinsic resiliency against physical and side channels attacks. We study three classes of PUFs properties to design pertinent test methods: (i) predictability, (ii) sensitivity to component accuracy, and (iii) susceptibility to reverse engineering. As our case studies, we analyze two popular PUF structures, linear and feed-forward, and show that their security is not adequate from several points of view. The technical highlights of the paper are the first non-destructive technique for PUF reverse engineering and a new PUF structure that is capable of passing our security tests.
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paper_title: PUF Modeling Attacks on Simulated and Silicon Data

paper_content:

We discuss numerical modeling attacks on several proposed strong physical unclonable functions (PUFs). Given a set of challenge-response pairs (CRPs) of a Strong PUF, the goal of our attacks is to construct a computer algorithm which behaves indistinguishably from the original PUF on almost all CRPs. If successful, this algorithm can subsequently impersonate the Strong PUF, and can be cloned and distributed arbitrarily. It breaks the security of any applications that rest on the Strong PUF's unpredictability and physical unclonability. Our method is less relevant for other PUF types such as Weak PUFs. The Strong PUFs that we could attack successfully include standard Arbiter PUFs of essentially arbitrary sizes, and XOR Arbiter PUFs, Lightweight Secure PUFs, and Feed-Forward Arbiter PUFs up to certain sizes and complexities. We also investigate the hardness of certain Ring Oscillator PUF architectures in typical Strong PUF applications. Our attacks are based upon various machine learning techniques, including a specially tailored variant of logistic regression and evolution strategies. Our results are mostly obtained on CRPs from numerical simulations that use established digital models of the respective PUFs. For a subset of the considered PUFs-namely standard Arbiter PUFs and XOR Arbiter PUFs-we also lead proofs of concept on silicon data from both FPGAs and ASICs. Over four million silicon CRPs are used in this process. The performance on silicon CRPs is very close to simulated CRPs, confirming a conjecture from earlier versions of this work. Our findings lead to new design requirements for secure electrical Strong PUFs, and will be useful to PUF designers and attackers alike.
---
paper_title: FPGA Intrinsic PUFs and Their Use for IP Protection

paper_content:

In recent years, IP protection of FPGA hardware designs has become a requirement for many IP vendors. In [34], Simpson and Schaumont proposed a fundamentally different approach to IP protection on FPGAs based on the use of Physical Unclonable Functions (PUFs). Their work only assumes the existence of a PUF on the FPGAs without actually proposing a PUF construction. In this paper, we propose new protocols for the IP protection problem on FPGAs and provide the first construction of a PUF intrinsic to current FPGAs based on SRAM memory randomness present on current FPGAs. We analyze SRAM-based PUF statistical properties and investigate the trade offs that can be made when implementing a fuzzy extractor.
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paper_title: Modeling attacks on physical unclonable functions

paper_content:

We show in this paper how several proposed Physical Unclonable Functions (PUFs) can be broken by numerical modeling attacks. Given a set of challenge-response pairs (CRPs) of a PUF, our attacks construct a computer algorithm which behaves indistinguishably from the original PUF on almost all CRPs. This algorithm can subsequently impersonate the PUF, and can be cloned and distributed arbitrarily. This breaks the security of essentially all applications and protocols that are based on the respective PUF. The PUFs we attacked successfully include standard Arbited PUFs and Ring Oscillator PUFs of arbitrary sizes, and XO Arbiter PUFs, Lightweight Secure PUFs, and Feed-Forward Arbiter PUFs of up to a given size and complexity. Our attacks are based upon various machine learning techniques including Logistic Regression and Evolution Strategies. Our work leads to new design requirements for secure electrical PUFs, and will be useful to PUF designers and attackers alike.
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paper_title: Slender PUF Protocol: A Lightweight, Robust, and Secure Authentication by Substring Matching

paper_content:

We introduce Slender PUF protocol, an efficient and secure method to authenticate the responses generated from a Strong Physical Unclonable Function (PUF). The new method is lightweight, and suitable for energy constrained platforms such as ultra-low power embedded systems for use in identification and authentication applications. The proposed protocol does not follow the classic paradigm of exposing the full PUF responses (or a transformation of the full string of responses) on the communication channel. Instead, random subsets of the responses are revealed and sent for authentication. The response patterns are used for authenticating the prover device with a very high probability. We perform a thorough analysis of the method's resiliency to various attacks which guides adjustment of our protocol parameters for an efficient and secure implementation. We demonstrate that Slender PUF protocol, if carefully designed, will be resilient against all known machine learning attacks. In addition, it has the great advantage of an inbuilt PUF error tolerance. Thus, Slender PUF protocol is lightweight and does not require costly additional error correction, fuzzy extractors, and hash modules suggested in most previously known PUF-based robust authentication techniques. The low overhead and practicality of the protocol are confirmed by a set of hardware implementation and evaluations.
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paper_title: Recyclable PUFs: logically reconfigurable PUFs

paper_content:

Physically Unclonable Functions (PUFs) are security primitives that exploit intrinsic random physical variations of hardware components. In the recent years, many security solutions based on PUFs have been proposed, including identification/authentication schemes, key storage and hardware-entangled cryptography. Existing PUF instantiations typically exhibit a static challenge/response behavior, while many practical applications would benefit from reconfigurable PUFs. Examples include the revocation or update of “secrets” in PUF-based key storage or cryptographic primitives based on PUFs. In this paper, we present the concept of logically reconfigurable PUFs (LR-PUFs) that allow changing the challenge/response behavior without physically replacing or modifying the underlying PUF. We present two efficient LR-PUF constructions and evaluate their performance and security. In this context, we introduce a formal security model for LR-PUFs. Finally, we discuss several practical applications of LR-PUFs focusing on lightweight solutions for resource-constrained embedded devices, in particular RFIDs.
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paper_title: Reverse Fuzzy Extractors: Enabling Lightweight Mutual Authentication for PUF-Enabled RFIDs

paper_content:

RFID-based tokens are increasingly used in electronic payment and ticketing systems for mutual authentication of tickets and terminals. These systems typically use cost-effective tokens without expensive hardware protection mechanisms and are exposed to hardware attacks that copy and maliciously modify tokens. Physically Unclonable Functions (PUFs) are a promising technology to protect against such attacks by binding security critical data to the physical characteristics of the underlying hardware. However, existing PUF-based authentication schemes for RFID do not support mutual authentication, are often vulnerable to emulation and denial-of service attacks, and allow only for a limited number of authentications.
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paper_title: Design and Implementation of PUF-Based "Unclonable" RFID ICs for Anti-Counterfeiting and Security Applications

paper_content:

Physical unclonable functions (PUFs) exploit the physical characteristics of the silicon and the IC manufacturing process variations to uniquely characterize each and every silicon chip. Since it is practically impossible to model, copy, or control the IC manufacturing process variations, PUFs not only make these chips unique, but also effectively unclonable. Exploiting the inherent variations in the IC manufacturing process, PUFs provide a secure, robust, low cost mechanism to authenticate silicon chips. This makes PUFs attractive for RFID ICs where cost and security are the key requirements. In this paper we present the design and implementation of PUF enabled "unclonable" RFIDs. The PUF-enabled RFID has been fabricated in 0.18 mu technology, and extensive testing results demonstrate that PUFs can securely authenticate an RFID with minimal overheads. We also highlight the advantages of PUF based RFIDs in anti-counterfeiting and security applications.
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paper_title: A noise bifurcation architecture for linear additive physical functions

paper_content:

Physical Unclonable Functions (PUFs) allow a silicon device to be authenticated based on its manufacturing variations using challenge/response evaluations. Popular realizations use linear additive functions as building blocks. Security is scaled up using non-linear mixing (e.g., adding XORs). Because the responses are physically derived and thus noisy, the resulting explosion in noise impacts both the adversary (which is desirable) as well as the verifier (which is undesirable). We present the first architecture for linear additive physical functions where the noise seen by the adversary and the noise seen by the verifier are bifurcated by using a randomized decimation technique and a novel response recovery method at an authentication verification server. We allow the adversary's noise η ::: a ::: → 0.50 while keeping the verifier's noise η ::: v ::: constant, using a parameter-based authentication modality that does not require explicit challenge/response pair storage at the server. We present supporting data using 28nm FPGA PUF noise results as well as machine learning attack results. We demonstrate that our architecture can also withstand recent side-channel attacks that filter the noise (to clean up training challenge/response labels) prior to machine learning.
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paper_title: Reverse Fuzzy Extractors: Enabling Lightweight Mutual Authentication for PUF-Enabled RFIDs

paper_content:

RFID-based tokens are increasingly used in electronic payment and ticketing systems for mutual authentication of tickets and terminals. These systems typically use cost-effective tokens without expensive hardware protection mechanisms and are exposed to hardware attacks that copy and maliciously modify tokens. Physically Unclonable Functions (PUFs) are a promising technology to protect against such attacks by binding security critical data to the physical characteristics of the underlying hardware. However, existing PUF-based authentication schemes for RFID do not support mutual authentication, are often vulnerable to emulation and denial-of service attacks, and allow only for a limited number of authentications.
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paper_title: IBIHOP: Proper Privacy Preserving Mutual RFID Authentication.

paper_content:

One of the concerns that comes with the use of RFID tags is that these respond to any query. This can be overcome by having mutual authentication between reader and tag. However, the ordering between the two authentication steps is crucial. In this paper, we formalise mutual RFID authentication: capturing the necessary coupling between tag authentication and reader authentication as well as the ordering between these authentication steps. We show that the reader needs to authenticate first to the yet unknown tag to 1) preserve the tag’s privacy, 2) make it more resistant to side-channel analysis and 3) ensure that the end-user can observe the protocol’s output. We propose a generic construction to transform existing private RFID authentication protocols into proper private RFID mutual authentication protocols. Finally, we design a very efficient wide-strong private RFID mutual authentication protocol that requires the tag to compute only three scalar-elliptic curve point multiplications. We also show how this new protocol can be implemented efficiently in hardware.
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paper_title: Enhancing RFID Security and Privacy by Physically Unclonable Functions

paper_content:

Radio frequency identification (RFID) is a technology that enables RFID readers to perform fully automatic wireless identification of objects that are labeled with RFID tags. Initially, this technology was mainly used for electronic labeling of pallets, cartons, and products to enable seamless supervision of supply chains. Today, RFID technology is widely deployed to many other applications as well, including animal and product identification [2, 42], access control [2, 47], electronic tickets [47] and passports [27], and even human implantation [30].
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paper_title: RFID-tags for Anti-Counterfeiting

paper_content:

RFID-tags are becoming very popular tools for identification of products. As they have a small microchip on board, they offer functionality that can be used for security purposes. This chip functionality makes it possible to verify the authenticity of a product and hence to detect and prevent counterfeiting. In order to be successful for these security purposes too, RFID-tags have to be resistant against many attacks, in particular against cloning of the tag. In this paper, we investigate how an RFID-tag can be made unclonable by linking it inseparably to a Physical Unclonable Function (PUF). We present the security protocols that are needed for the detection of the authenticity of a product when it is equipped with such a system. We focus on off-line authentication because it is very attractive from a practical point of view. We show that a PUF based solution for RFID-tags is feasible in the off-line case.
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paper_title: A PUF-based ultra-lightweight mutual-authentication RFID protocol

paper_content:

Radio Frequency Identification (RFID) is a technology used for automatic identification of objects, people, and virtually anything one can think of. Applications of RFID technology are expanding and its usage has been adopted worldwide. As such, major efforts have been made to secure the communications in RFID systems and to protect them from various attacks. This paper surveys RFID security vulnerabilities and some of the proposed solutions that guard against these vulnerabilities. Then, a novel approach to achieve mutual authentication for ultra-lightweight tags is proposed using Physically Unclonable Functions (PUFs). The proposed approach provides robust security properties as well as good performance.
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paper_title: PUF-enhanced offline RFID security and privacy

paper_content:

RFID (Radio Frequency IDentification) based communication solutions have been widely used nowadays for mobile environments such as access control for secure system, ticketing systems for transportation, and sport events. These systems usually depend on readers that are not continuously connected to a secure backend system. Thus, the readers should be able to perform their duties even in offline mode, which generally requires the management by the readers of the susceptible data. The use of RFID may cause several security and privacy issues such as traceability of tag owner, malicious eavesdropping and cloning of tags. Besides, when a reader is compromised by an adversary, the solution to resolve these issues getting worse. In order to handle these issues, several RFID authentication protocols have been recently proposed; but almost none of them provide strong privacy for the tag owner. On the other hand, several frameworks have been proposed to analyze the security and privacy but none of them consider offline RFID system. Motivated by this need, in this paper, we first revisit Vaudenay's model, extend it by considering offline RFID system and introduce the notion of compromise reader attacks. Then, we propose an efficient RFID mutual authentication protocol. Our protocol is based on the use of physically unclonable functions (PUFs) which provide cost-efficient means to the fingerprint chips based on their physical properties. We prove that our protocol provides destructive privacy for tag owner even against reader attacks.
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paper_title: Physical One-Way Functions

paper_content:

Modern cryptographic practice rests on the use of one-way functions, which are easy to evaluate but difficult to invert. Unfortunately, commonly used one-way functions are either based on unproven conjectures or have known vulnerabilities. We show that instead of relying on number theory, the mesoscopic physics of coherent transport through a disordered medium can be used to allocate and authenticate unique identifiers by physically reducing the medium's microstructure to a fixed-length string of binary digits. These physical one-way functions are inexpensive to fabricate, prohibitively difficult to duplicate, admit no compact mathematical representation, and are intrinsically tamper-resistant. We provide an authentication protocol based on the enormous address space that is a principal characteristic of physical one-way functions.
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paper_title: Efficient and practical authentication of PUF-based RFID tags in supply chains

paper_content:

We propose new methodologies for the authentication of RFID tags along supply chains, exploiting tags equipped with a Physical Unclonable Function (PUF) device. Unlike state-of-the-art approaches that require sharing a large database of challenge-response pairs (CRPs), we achieve a constant amount of shared secret data, oblivious of the number of CRPs and tags to be handled. Such data can be distributed using a secure hardware token. The rest of the data can be released over an insecure one-way communication channel that can be realized by shipping storage media along with goods. We discuss the applicative scenario and perform experiments on pre-production PUF-based tags in order to assess the applicability of our approaches.
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paper_title: Design and Implementation of PUF-Based "Unclonable" RFID ICs for Anti-Counterfeiting and Security Applications

paper_content:

Physical unclonable functions (PUFs) exploit the physical characteristics of the silicon and the IC manufacturing process variations to uniquely characterize each and every silicon chip. Since it is practically impossible to model, copy, or control the IC manufacturing process variations, PUFs not only make these chips unique, but also effectively unclonable. Exploiting the inherent variations in the IC manufacturing process, PUFs provide a secure, robust, low cost mechanism to authenticate silicon chips. This makes PUFs attractive for RFID ICs where cost and security are the key requirements. In this paper we present the design and implementation of PUF enabled "unclonable" RFIDs. The PUF-enabled RFID has been fabricated in 0.18 mu technology, and extensive testing results demonstrate that PUFs can securely authenticate an RFID with minimal overheads. We also highlight the advantages of PUF based RFIDs in anti-counterfeiting and security applications.
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paper_title: Physical One-Way Functions

paper_content:

Modern cryptographic practice rests on the use of one-way functions, which are easy to evaluate but difficult to invert. Unfortunately, commonly used one-way functions are either based on unproven conjectures or have known vulnerabilities. We show that instead of relying on number theory, the mesoscopic physics of coherent transport through a disordered medium can be used to allocate and authenticate unique identifiers by physically reducing the medium's microstructure to a fixed-length string of binary digits. These physical one-way functions are inexpensive to fabricate, prohibitively difficult to duplicate, admit no compact mathematical representation, and are intrinsically tamper-resistant. We provide an authentication protocol based on the enormous address space that is a principal characteristic of physical one-way functions.
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paper_title: Controlled physical random functions

paper_content:

A physical random function (PUF) is a random function that can only be evaluated with the help of a complex physical system. We introduce controlled physical random functions (CPUFs) which are PUFs that can only be accessed via an algorithm that is physically bound to the PUF in an inseparable way. CPUFs can be used to establish a shared secret between a physical device and a remote user. We present protocols that make this possible in a secure and flexible way, even in the case of multiple mutually mistrusting parties. Once established, the shared secret can be used to enable a wide range of applications. We describe certified execution, where a certificate is produced that proves that a specific computation was carried out on a specific processor. Certified execution has many benefits, including protection against malicious nodes in distributed computation networks. We also briefly discuss a software licensing application.
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paper_title: Silicon physical random functions

paper_content:

We introduce the notion of a Physical Random Function (PUF). We argue that a complex integrated circuit can be viewed as a silicon PUF and describe a technique to identify and authenticate individual integrated circuits (ICs).We describe several possible circuit realizations of different PUFs. These circuits have been implemented in commodity Field Programmable Gate Arrays (FPGAs). We present experiments which indicate that reliable authentication of individual FPGAs can be performed even in the presence of significant environmental variations.We describe how secure smart cards can be built, and also briefly describe how PUFs can be applied to licensing and certification applications.
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paper_title: Controlled physical random functions and applications

paper_content:

The cryptographic protocols that we use in everyday life rely on the secure storage of keys in consumer devices. Protecting these keys from invasive attackers, who open a device to steal its key, is a challenging problem. We propose controlled physical random functions (CPUFs) as an alternative to storing keys and describe the core protocols that are needed to use CPUFs. A physical random functions (PUF) is a physical system with an input and output. The functional relationship between input and output looks like that of a random function. The particular relationship is unique to a specific instance of a PUF, hence, one needs access to a particular PUF instance to evaluate the function it embodies. The cryptographic applications of a PUF are quite limited unless the PUF is combined with an algorithm that limits the ways in which the PUF can be evaluated; this is a CPUF. A major difficulty in using CPUFs is that you can only know a small set of outputs of the PUF—the unknown outputs being unrelated to the known ones. We present protocols that get around this difficulty and allow a chain of trust to be established between the CPUF manufacturer and a party that wishes to interact securely with the PUF device. We also present some elementary applications, such as certified execution.
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paper_title: Cryptanalysis of Lightweight Mutual Authentication and Ownership Transfer for RFID Systems

paper_content:

Radio Frequency Identification (RFID) is a technology increasingly used in many applications for object identification. Ownership transfer of RFID tags is also another important requirement for some applications. Namely, the owner of an RFID tag may be required to change several times during its life-cycle. For an ownership transfer, the server of the new owner takes over tag authorization in order to have a secure communication with the tag by obtaining necessary private information from the old owner. Security and privacy are two major concerns for these applications, and they are definitely critical points when tags are required to provide a proof of identity. However, it is a challenging task to design an authentication protocol due to the limited resource of low-cost RFID tags. Kulseng \textit{et al.} recently proposed a lightweight RFID authentication protocol at INFOCOM 2010. They also extended this scheme to secure the ownership transfer of RFID tags. Both protocols use a combination of Physically Unclonable Functions (PUFs) and Linear Feedback Shift Registers (LFSRs). They claim that in this way the number of gates can be significantly decreased and the most efficient protocol can be obtained with respect to the existing protocols. In this paper, we revisit their protocol and show that there are actually several serious protocol issues which compromises the overall security. First of all, they claim that the message blocking attack works only if the final message is blocked. However, we show that this attack still works between the reader and the tag even if the third message is blocked or dropped. Secondly, we show that their protocols are not resistant message injection attack due to the lack of message integrity. We also highlight that the LFSR has been misused in their scheme which yields a vulnerability of privacy. Finally, their ownership transfer protocol does not provide tag privacy against the old owner of the tag.
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paper_title: Physically Unclonable Function-Based Security and Privacy in RFID Systems

paper_content:

Radio frequency identification (RFID) is an increasingly popular technology that uses radio signals for object identification. Tracking and authentication in RFID tags have raised many privacy and security concerns. On the other hand, known privacy and security cryptographic defenses are too hardware-expensive to incorporate into low-cost RFID tags. In this paper, we propose hardware-based approaches to RFID security that rely on physically unclonable functions (PUFs). These functions exploit the inherent variability of wire delays and parasitic gate delays in manufactured circuits, and may be implemented with an order-of-magnitude reduction in gate count as compared with traditional cryptographic functions. We describe protocols for privacy-preserving tag identification and secure message authentication codes. We compare PUFs to digital cryptographic functions, address other uses of PUFs to enhance RFID security and suggest interesting directions for future research. The proposed solutions are efficient, practical, and appropriate for low-cost RFID systems
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paper_title: Physical unclonable functions for device authentication and secret key generation

paper_content:

Physical Unclonable Functions (PUFs) are innovative circuit primitives that extract secrets from physical characteristics of integrated circuits (ICs). We present PUF designs that exploit inherent delay characteristics of wires and transistors that differ from chip to chip, and describe how PUFs can enable low-cost authentication of individual ICs and generate volatile secret keys for cryptographic operations.
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paper_title: Reverse Fuzzy Extractors: Enabling Lightweight Mutual Authentication for PUF-Enabled RFIDs

paper_content:

RFID-based tokens are increasingly used in electronic payment and ticketing systems for mutual authentication of tickets and terminals. These systems typically use cost-effective tokens without expensive hardware protection mechanisms and are exposed to hardware attacks that copy and maliciously modify tokens. Physically Unclonable Functions (PUFs) are a promising technology to protect against such attacks by binding security critical data to the physical characteristics of the underlying hardware. However, existing PUF-based authentication schemes for RFID do not support mutual authentication, are often vulnerable to emulation and denial-of service attacks, and allow only for a limited number of authentications.
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paper_title: Lightweight Mutual Authentication and Ownership Transfer for RFID Systems

paper_content:

The promise of RFID technology has been evidently foreseeable due to the low cost and high convenience value of RFID tags. However, the low-cost RFID tags poses new challenges to security and privacy. Some solutions utilize expensive cryptographic primitives such as hash or encryption functions, and some lightweight approaches have been reported to be broken. In this paper, we propose a lightweight solution to Mutual Authentication for RFID systems in which only the authenticated readers and tags can successfully communicate with each other. Then, we adapt our Mutual Authentication scheme to secure the Ownership Transfer of RFID tags. Our mutual authentication and ownership transfer protocols are realized utilizing minimalistic cryptography such as Physically Unclonable Functions (PUF) and Linear Feedback Shift Registers (LFSR). PUFs and LFSRs are very efficient in hardware and particularly suitable for the low-cost RFID tags. Compared to existing solutions built on top of hash functions that require 8000 to 10000 gates, our schemes demand only 784 gates for 64-bit variables and can be easily accommodated by the cheapest RFID tags with only 2000 gates available for security functions.
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paper_title: Enhancing RFID Security and Privacy by Physically Unclonable Functions

paper_content:

Radio frequency identification (RFID) is a technology that enables RFID readers to perform fully automatic wireless identification of objects that are labeled with RFID tags. Initially, this technology was mainly used for electronic labeling of pallets, cartons, and products to enable seamless supervision of supply chains. Today, RFID technology is widely deployed to many other applications as well, including animal and product identification [2, 42], access control [2, 47], electronic tickets [47] and passports [27], and even human implantation [30].
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paper_title: Recyclable PUFs: logically reconfigurable PUFs

paper_content:

Physically Unclonable Functions (PUFs) are security primitives that exploit intrinsic random physical variations of hardware components. In the recent years, many security solutions based on PUFs have been proposed, including identification/authentication schemes, key storage and hardware-entangled cryptography. Existing PUF instantiations typically exhibit a static challenge/response behavior, while many practical applications would benefit from reconfigurable PUFs. Examples include the revocation or update of “secrets” in PUF-based key storage or cryptographic primitives based on PUFs. In this paper, we present the concept of logically reconfigurable PUFs (LR-PUFs) that allow changing the challenge/response behavior without physically replacing or modifying the underlying PUF. We present two efficient LR-PUF constructions and evaluate their performance and security. In this context, we introduce a formal security model for LR-PUFs. Finally, we discuss several practical applications of LR-PUFs focusing on lightweight solutions for resource-constrained embedded devices, in particular RFIDs.
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paper_title: On the Pitfalls of Using Arbiter-PUFs as Building Blocks

paper_content:

Physical unclonable functions (PUFs) have emerged as a promising solution for securing resource-constrained embedded devices such as RFID tokens. PUFs use the inherent physical differences of every chip to either securely authenticate the chip or generate cryptographic keys without the need of nonvolatile memory. However, PUFs have shown to be vulnerable to model building attacks if the attacker has access to challenge and response pairs. In these model building attacks, machine learning is used to determine the internal parameters of the PUF to build an accurate software model. Nevertheless, PUFs are still a promising building block and several protocols and designs have been proposed that are believed to be resistant against machine learning attacks. In this paper, we take a closer look at two such protocols, one based on reverse fuzzy extractors and one based on pattern matching. We show that it is possible to attack these protocols using machine learning despite the fact that an attacker does not have access to direct challenge and response pairs. The introduced attacks demonstrate that even highly obfuscated responses can be used to attack PUF protocols. Hence, this paper shows that even protocols in which it would be computationally infeasible to compute enough challenge and response pairs for a direct machine learning attack can be attacked using machine learning.
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paper_title: PUF-based secure test wrapper design for cryptographic SoC testing

paper_content:

Globalization of the semiconductor industry increases the vulnerability of integrated circuits. This particularly becomes a major concern for cryptographic IP blocks integrated on a System-on-Chip (SoC). The trustworthiness of these cryptographic blocks can be ensured with a secure test strategy. Presently, the IEEE 1500 Test Wrapper has emerged as the test standard for industrial SoCs. Additionally a secure activation mechanism has been proposed to this standard in order to restrict access to the testing interface to eligible testers by using a cryptographic authentication mechanism. This access mechanism is necessary in order not to provide any side-channels which may leak secret information for attackers. However, this approach requires the authentication mechanism to be implemented in hardware incurring an area overhead, and the authentication secrets to be securely stored in non-volatile memory (NVM), which may be susceptible to side-channel attacks. In this work, we enhance the secure test wrapper allowing testing of multiple IP blocks using a PUF-based authentication mechanism which overcomes the necessity of secure NVM and reduces the implementation overhead.
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paper_title: Mutual Authentication Protocol for Enhanced RFID Security and Anti-counterfeiting

paper_content:

Radio Frequency Identification (RFID) is a technology that has been widely used in daily life, such as in access control, in electronic passports, public transportation, payment and ticketing. The reader communicates with the RFID tags using a wireless channel where the security and privacy requirements are satisfied via cryptographic building blocks (e. g, hash functions, symmetric encryptions and secure authentication protocol). However, since the RFID information may be easily unveiled over the air, security and the privacy issues always exist. In this paper, we propose a new mutual authentication protocol in RFID systems. This protocol uses an ID tag which is encrypted with a hash function and a stream cipher based OTP by challenge-response pair of a PUF (Physically Unclonable Function), thus there is no key disclosure problem in our protocol. NLM-128 stream cipher is used to generate the OTP value, it provides low-resource hardware implementation, which is appropriate for ubiquitous computing devices such as a sensor in USN or a RFID tag. It takes a 128-bit key and a 128-bit initialization vector, has 258-bits of internal stage, and achieves a security level of 2128.
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paper_title: Breaking NLM-MAC Generator

paper_content:

NLM generator, designed by HoonJae Lee, SangMin Sung, HyeongRag Kim, is the strengthened version of the LM-type summation generator with two memory bits; which uses non-linear combination of linear feedback shift register and non-linear feedback shift register. Recently, the cipher along with a massage authenticate function have been proposed for a lightweight communication framework in wireless sensor networks. Also, the generator has been used in two different RFID mutual authentication protocols and a protocol to secure access in internet. This paper indicates some critical cryptographic weak points leading to the key recovery and forgery attack. We prove the internal state of NLMn can be recovered with time complexity about nlog7×2 where the total length of internal state is 2 · n + 2 bits. The attack needs about n keystream bits. We also show attacker is able forge any MAC tag in real time by having only one pair (MAC tag, cipher-text). The proposed attacks are completely practical and break the scheme with negligible error probability.
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paper_title: PUF-Based RFID authentication protocol against secret key leakage

paper_content:

RFID tags are now pervasive in our everyday life. They raise a lot of security and privacy issues. Many authentication protocols against these problems assume that the tags can contain a secret key that is unknown to the adversary. However, physical attacks can lead to key exposure and full security breaks. On the other hand, many protocols are only described and analyzed. However, we cannot explain why they are designed like that. Compare with the previous protocols, we first propose a universal RFID authentication protocol and show the principle why the protocol is designed. It can be instantiated for various types and achieve different security properties according to the implementation of the functions. Then we introduce a general prototype of delay-based PUF for low-cost RFID systems and propose a new lightweight RFID authentication protocol based on the general prototype of PUF. The new protocol not only resists the physical attacks and secret key leakage, but also prevents the asynchronization between the reader and the tag. It also can resist the replay attack, man-in-the-middle attack etc. Finally, we show that it is efficient and practical for low-cost RFID systems.
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paper_title: Lightweight Mutual Authentication and Ownership Transfer for RFID Systems

paper_content:

The promise of RFID technology has been evidently foreseeable due to the low cost and high convenience value of RFID tags. However, the low-cost RFID tags poses new challenges to security and privacy. Some solutions utilize expensive cryptographic primitives such as hash or encryption functions, and some lightweight approaches have been reported to be broken. In this paper, we propose a lightweight solution to Mutual Authentication for RFID systems in which only the authenticated readers and tags can successfully communicate with each other. Then, we adapt our Mutual Authentication scheme to secure the Ownership Transfer of RFID tags. Our mutual authentication and ownership transfer protocols are realized utilizing minimalistic cryptography such as Physically Unclonable Functions (PUF) and Linear Feedback Shift Registers (LFSR). PUFs and LFSRs are very efficient in hardware and particularly suitable for the low-cost RFID tags. Compared to existing solutions built on top of hash functions that require 8000 to 10000 gates, our schemes demand only 784 gates for 64-bit variables and can be easily accommodated by the cheapest RFID tags with only 2000 gates available for security functions.
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paper_title: Slender PUF Protocol: A Lightweight, Robust, and Secure Authentication by Substring Matching

paper_content:

We introduce Slender PUF protocol, an efficient and secure method to authenticate the responses generated from a Strong Physical Unclonable Function (PUF). The new method is lightweight, and suitable for energy constrained platforms such as ultra-low power embedded systems for use in identification and authentication applications. The proposed protocol does not follow the classic paradigm of exposing the full PUF responses (or a transformation of the full string of responses) on the communication channel. Instead, random subsets of the responses are revealed and sent for authentication. The response patterns are used for authenticating the prover device with a very high probability. We perform a thorough analysis of the method's resiliency to various attacks which guides adjustment of our protocol parameters for an efficient and secure implementation. We demonstrate that Slender PUF protocol, if carefully designed, will be resilient against all known machine learning attacks. In addition, it has the great advantage of an inbuilt PUF error tolerance. Thus, Slender PUF protocol is lightweight and does not require costly additional error correction, fuzzy extractors, and hash modules suggested in most previously known PUF-based robust authentication techniques. The low overhead and practicality of the protocol are confirmed by a set of hardware implementation and evaluations.
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paper_title: Robust and Reverse-Engineering Resilient PUF Authentication and Key-Exchange by Substring Matching

paper_content:

This paper proposes novel robust and low-overhead physical unclonable function (PUF) authentication and key exchange protocols that are resilient against reverse-engineering attacks. The protocols are executed between a party with access to a physical PUF (prover) and a trusted party who has access to the PUF compact model (verifier). The proposed protocols do not follow the classic paradigm of exposing the full PUF responses or a transformation of them. Instead, random subsets of the PUF response strings are sent to the verifier so the exact position of the subset is obfuscated for the third-party channel observers. Authentication of the responses at the verifier side is done by matching the substring to the available full response string; the index of the matching point is the actual obfuscated secret (or key) and not the response substring itself. We perform a thorough analysis of resiliency of the protocols against various adversarial acts, including machine learning and statistical attacks. The attack analysis guides us in tuning the parameters of the protocol for an efficient and secure implementation. The low overhead and practicality of the protocols are evaluated and confirmed by hardware implementation.
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paper_title: Slender PUF Protocol: A Lightweight, Robust, and Secure Authentication by Substring Matching

paper_content:

We introduce Slender PUF protocol, an efficient and secure method to authenticate the responses generated from a Strong Physical Unclonable Function (PUF). The new method is lightweight, and suitable for energy constrained platforms such as ultra-low power embedded systems for use in identification and authentication applications. The proposed protocol does not follow the classic paradigm of exposing the full PUF responses (or a transformation of the full string of responses) on the communication channel. Instead, random subsets of the responses are revealed and sent for authentication. The response patterns are used for authenticating the prover device with a very high probability. We perform a thorough analysis of the method's resiliency to various attacks which guides adjustment of our protocol parameters for an efficient and secure implementation. We demonstrate that Slender PUF protocol, if carefully designed, will be resilient against all known machine learning attacks. In addition, it has the great advantage of an inbuilt PUF error tolerance. Thus, Slender PUF protocol is lightweight and does not require costly additional error correction, fuzzy extractors, and hash modules suggested in most previously known PUF-based robust authentication techniques. The low overhead and practicality of the protocol are confirmed by a set of hardware implementation and evaluations.
---
paper_title: On the Pitfalls of Using Arbiter-PUFs as Building Blocks

paper_content:

Physical unclonable functions (PUFs) have emerged as a promising solution for securing resource-constrained embedded devices such as RFID tokens. PUFs use the inherent physical differences of every chip to either securely authenticate the chip or generate cryptographic keys without the need of nonvolatile memory. However, PUFs have shown to be vulnerable to model building attacks if the attacker has access to challenge and response pairs. In these model building attacks, machine learning is used to determine the internal parameters of the PUF to build an accurate software model. Nevertheless, PUFs are still a promising building block and several protocols and designs have been proposed that are believed to be resistant against machine learning attacks. In this paper, we take a closer look at two such protocols, one based on reverse fuzzy extractors and one based on pattern matching. We show that it is possible to attack these protocols using machine learning despite the fact that an attacker does not have access to direct challenge and response pairs. The introduced attacks demonstrate that even highly obfuscated responses can be used to attack PUF protocols. Hence, this paper shows that even protocols in which it would be computationally infeasible to compute enough challenge and response pairs for a direct machine learning attack can be attacked using machine learning.
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paper_title: Attacking PUF-Based Pattern Matching Key Generators via Helper Data Manipulation

paper_content:

Physically Unclonable Functions (PUFs) provide a unique signature for integrated circuits (ICs), similar to a fingerprint for humans. They are primarily used to generate secret keys, hereby exploiting the unique manufacturing variations of an IC. Unfortunately, PUF output bits are not perfectly reproducible and non-uniformly distributed. To obtain a high-quality key, one needs to implement additional post-processing logic on the same IC. Fuzzy extractors are the well-established standard solution. Pattern Matching Key Generators (PMKGs) have been proposed as an alternative. In this work, we demonstrate the latter construction to be vulnerable against manipulation of its public helper data. Full key recovery is possible, although depending on system design choices. We demonstrate our attacks using a 4-XOR arbiter PUF, manufactured in 65nm CMOS technology. We also propose a simple but effective countermeasure.
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paper_title: Design of a Security Protocol for Low-Cost RFID

paper_content:

To solve the security problems in low-cost RFID system, we propose a protocol based on key-chain. Taking full advantage of features that the back-end database can store a lot of keys and the PUF circuit can generate a large number of non-replication keys, the protocol compares challenge/response key pairs obtained from PUF operation in the tag with key stored in the back-end database. And then the protocol achieves mutual authentication with high security.
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paper_title: High-Efficient RFID Authentication Protocol Based on Physical Unclonable Function

paper_content:

RFID(Radio Frequency Identiﬁcation) is an increasingly popular technology that uses radio signals for object identiﬁcation. Tracking and authentication in RFID tags have raised many privacy and security concerns.Known privacy and security cryptographic defenses are too hardware-expensive to incorporate into low-cost RFID tags.This paper presents a low-cost and efficiency security protocol based on Physical Unclonable Functions(PUF), which solved the problems of existing security authentication protocol and can resist eavesdropping attack, replay attack, physical attack and tracking attack, with forward-security and backward-security.
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paper_title: Keying Hash Functions for Message Authentication

paper_content:

The use of cryptographic hash functions like MD5 or SHA-1 for message authentication has become a standard approach in many applications, particularly Internet security protocols. Though very easy to implement, these mechanisms are usually based on ad hoc techniques that lack a sound security analysis. ::: ::: We present new, simple, and practical constructions of message authentication schemes based on a cryptographic hash function. Our schemes, NMAC and HMAC, are proven to be secure as long as the underlying hash function has some reasonable cryptographic strengths. Moreover we show, in a quantitative way, that the schemes retain almost all the security of the underlying hash function. The performance of our schemes is essentially that of the underlying hash function. Moreover they use the hash function (or its compression function) as a black box, so that widely available library code or hardwair can be used to implement them in a simple way, and replaceability of the underlying hash function is easily supported.
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paper_title: HRP: A HMAC-based RFID mutual authentication protocol using PUF

paper_content:

RFID is one of the promising automatic identification systems. However, RFID is vulnerable to various threats such as tracking ID, cloning attack, spoofing attack, etc. Some mutual authentication protocols utilize cryptographic functions such as hash, but retrieving efficiency is very low. A naive challenge-response protocols based on PUF which is innovative circuit primitives require maintaining huge challenge-response pairs. Some lightweight protocols based on PUF have been reported to be broken. This paper proposes a HMAC-based mutual authentication protocol using PUF for RFID to address the problems of previous protocols as above mentioned. The proposed protocol provides robust security properties as well as efficient enough for the active tags in terms of the computation.
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paper_title: Mutual authentication in wireless body sensor networks (WBSN) based on Physical Unclonable Function (PUF)

paper_content:

Wireless sensor networks are capable of deploying large, self-organized and adaptable sets of sensors for military, environmental, healthcare, remote monitoring and many other applications. Unfortunately, the simplicity and low-cost nature of these sensors make it easy for attackers to clone the authentication protocol of compromised nodes in the network. Due to unprotected nature of the wireless sensor networks, an adversary can capture messages and compromise the safety of the sensor nodes, make replicas of the authentication codes and then launch a variety of attacks with these clones. In this paper, we propose a new mutual authentication scheme for the wireless body sensor networks which is based on a Physical Unclonable Function (PUF). To identify between the sink and nodes we use a pair of challenge-response values, which are generated by the PUF in each sensor node. Also, each node needs to complete the hashed and MAC operations in the entire verification process. Analysis indicates that the scheme is efficient and robust against different attacks, such as clone attacks, replay attack, etc.
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paper_title: A noise bifurcation architecture for linear additive physical functions

paper_content:

Physical Unclonable Functions (PUFs) allow a silicon device to be authenticated based on its manufacturing variations using challenge/response evaluations. Popular realizations use linear additive functions as building blocks. Security is scaled up using non-linear mixing (e.g., adding XORs). Because the responses are physically derived and thus noisy, the resulting explosion in noise impacts both the adversary (which is desirable) as well as the verifier (which is undesirable). We present the first architecture for linear additive physical functions where the noise seen by the adversary and the noise seen by the verifier are bifurcated by using a randomized decimation technique and a novel response recovery method at an authentication verification server. We allow the adversary's noise η ::: a ::: → 0.50 while keeping the verifier's noise η ::: v ::: constant, using a parameter-based authentication modality that does not require explicit challenge/response pair storage at the server. We present supporting data using 28nm FPGA PUF noise results as well as machine learning attack results. We demonstrate that our architecture can also withstand recent side-channel attacks that filter the noise (to clean up training challenge/response labels) prior to machine learning.
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Title: A Survey on Lightweight Entity Authentication with Strong PUFs

Section 1: INTRODUCTION
Description 1: Write about the common authentication scenario involving a low-cost token and a resource-rich server, the objectives of entity authentication, and an overview of how the current work extends prior research including additional protocol analysis and token privacy.

Section 2: Secure Sketches and Fuzzy Extractors
Description 2: Discuss the reconstruction methods for PUF responses using secure sketches and fuzzy extractors, and describe their implementation details and helper data leakage considerations.

Section 3: PROTOCOL REQUIREMENTS
Description 3: Introduce the special protocol design requirements for PUFs, detailing each requirement such as complete specification, leakage resilience, and noisiness handling among others in subsections 3.1 to 3.10.

Section 4: AUTHENTICATION VIA PUF-BASED KEY GENERATION
Description 4: Present how conventional authentication protocols can be adapted by replacing key storage with PUF-based key generation to enhance physical security, and describe various references and existing literature in this context.

Section 5: STRONG PUF PROTOCOL ANALYSIS
Description 5: Chronologically describe and analyze the development of strong PUF protocols, covering various proposals and their evaluations, including the analysis of basic authentication methods, controlled PUFs, and other specific protocols up to the latest innovations.

Section 6: OVERVIEW AND DISCUSSION
Description 6: Summarize the findings from the protocol analysis, categorizing protocols into PUF-based key generation and strong PUF obfuscation, and discuss their security and practicality.

Section 7: CONCLUSION
Description 7: Conclude by summarizing the various studied protocols, emphasizing that although strong PUFs have not yet achieved ideal cryptographic properties, conventional PUF-based key generation provides a promising alternative for lightweight entity authentication, and suggest directions for future research.