A Touch of Evil: High-Assurance Cryptographic Hardware from Untrusted Components

The semiconductor industry is fully globalized and integrated circuits (ICs) are commonly defined, designed and fabricated in different premises across the world. This reduces production costs, but also exposes ICs to supply chain attacks, where insiders introduce malicious circuitry into the final products. Additionally, despite extensive post-fabrication testing, it is not uncommon for ICs with subtle fabrication errors to make it into production systems. While many systems may be able to tolerate a few byzantine components, this is not the case for cryptographic hardware, storing and computing on confidential data. For this reason, many error and backdoor detection techniques have been proposed over the years. So far all attempts have been either quickly circumvented, or come with unrealistically high manufacturing costs and complexity. This paper proposes Myst, a practical high-assurance architecture, that uses commercial off-the-shelf (COTS) hardware, and provides strong security guarantees, even in the presence of multiple malicious or faulty components. The key idea is to combine protective-redundancy with modern threshold cryptographic techniques to build a system tolerant to hardware trojans and errors. To evaluate our design, we build a Hardware Security Module that provides the highest level of assurance possible with COTS components. Specifically, we employ more than a hundred COTS secure crypto-coprocessors, verified to FIPS140-2 Level 4 tamper-resistance standards, and use them to realize high-confidentiality random number generation, key derivation, public key decryption and signing. Our experiments show a reasonable computational overhead (less than 1% for both Decryption and Signing) and an exponential increase in backdoor-tolerance as more ICs are added

SIGNCRYPTION ANALYZE

The aim of this paper is to provide an overview for the research that has been done so far in signcryption area. The paper also presents the extensions for the signcryption scheme and discusses the security in signcryption. The main contribution to this paper represents the implementation of the signcryption algorithm with the examples provided.ElGamal, elliptic curves, encryption, identity-based, proxy-signcryption, public key, ring-signcryption, RSA, signcryption

An efficient FIS and RSA based Signcryption Security Scheme

No Abstrac

Two results on spontaneous anonymous group signatures.

Chan Kwok Leong.Thesis (M.Phil.)--Chinese University of Hong Kong, 2005.Includes bibliographical references (leaves 72-78).Abstracts in English and Chinese.Chapter 1 --- Introduction --- p.1Chapter 2 --- Preliminaries --- p.4Chapter 2.1 --- Notation --- p.4Chapter 2.2 --- Cryptographic Primitives --- p.5Chapter 2.2.1 --- Symmetric Key Cryptography --- p.5Chapter 2.2.2 --- Asymmetric Key Cryptosystem --- p.6Chapter 2.2.3 --- Secure Hash Function --- p.7Chapter 2.2.4 --- Digital Signature --- p.8Chapter 2.2.5 --- Digital Certificate and Public Key Infrastructure --- p.8Chapter 2.3 --- Provable Security and Security Model --- p.9Chapter 2.3.1 --- Mathematics Background --- p.9Chapter 2.3.2 --- One-Way Function --- p.10Chapter 2.3.3 --- Candidate One-way Functions --- p.12Chapter 2.4 --- Proof Systems --- p.15Chapter 2.4.1 --- Zero-knowledge Protocol --- p.15Chapter 2.4.2 --- Proof-of-Knowledge Protocol --- p.17Chapter 2.4.3 --- Honest-Verifier Zero-Knowledge (HVZK) Proof of Knowl- edge Protocols (PoKs) --- p.18Chapter 2.5 --- Security Model --- p.19Chapter 2.5.1 --- Random Oracle Model --- p.19Chapter 2.5.2 --- Generic group model (GGM) --- p.20Chapter 3 --- Signature Scheme --- p.21Chapter 3.1 --- Introduction --- p.21Chapter 3.2 --- Security Notation for Digital Signature --- p.23Chapter 3.3 --- Security Proof for Digital Signature --- p.24Chapter 3.3.1 --- Random Oracle Model for Signature Scheme --- p.24Chapter 3.3.2 --- Adaptive Chosen Message Attack --- p.24Chapter 3.4 --- Schnorr Identification and Schnorr Signature --- p.25Chapter 3.4.1 --- Schnorr's ROS assumption --- p.26Chapter 3.5 --- Blind Signature --- p.27Chapter 4 --- Spontaneous Anonymous Group (SAG) Signature --- p.30Chapter 4.1 --- Introduction --- p.30Chapter 4.2 --- Background --- p.30Chapter 4.2.1 --- Group Signature --- p.30Chapter 4.2.2 --- Threshold Signature --- p.31Chapter 4.3 --- SAG signatures --- p.33Chapter 4.4 --- Formal Definitions and Constructions --- p.35Chapter 4.4.1 --- Ring-type construction --- p.36Chapter 4.4.2 --- CDS-type construction --- p.36Chapter 4.5 --- Discussion --- p.37Chapter 5 --- Blind Spontaneous Anonymous Signature --- p.39Chapter 5.1 --- Introduction --- p.39Chapter 5.2 --- Definition --- p.40Chapter 5.2.1 --- Security Model --- p.41Chapter 5.2.2 --- Definitions of security notions --- p.41Chapter 5.3 --- Constructing blind SAG signatures --- p.43Chapter 5.3.1 --- Blind SAG signature: CDS-type [1] --- p.43Chapter 5.3.2 --- "Blind SAG signature: ring-type [2, 3]" --- p.44Chapter 5.4 --- Security Analysis --- p.44Chapter 5.4.1 --- Multi-key parallel one-more unforgeability of blind signature --- p.45Chapter 5.4.2 --- Security of our blind SAG signatures --- p.47Chapter 5.5 --- Discussion --- p.49Chapter 6 --- Linkable Spontaneous Anonymous Group Signature --- p.51Chapter 6.1 --- introduction --- p.51Chapter 6.2 --- Related work --- p.51Chapter 6.3 --- Basic Building Blocks --- p.52Chapter 6.3.1 --- Proving the Knowledge of Several Discrete Logarithms --- p.53Chapter 6.3.2 --- Proving the Knowledge of d Out of n Equalities of Discrete Logarithms --- p.55Chapter 6.4 --- Security Model --- p.57Chapter 6.4.1 --- Syntax --- p.57Chapter 6.4.2 --- Notions of Security --- p.59Chapter 6.5 --- Our Construction --- p.63Chapter 6.5.1 --- An Linkable Threshold SAG Signature Scheme --- p.63Chapter 6.5.2 --- Security --- p.65Chapter 6.5.3 --- Discussions --- p.67Chapter 7 --- Conclusion --- p.70Bibliography --- p.7

Fair signature exchange via delegation on ubiquitous networks

This paper addresses the issue of autonomous fair signature exchange in emerging ubiquitous (u-) commerce systems, which require that the exchange task be delegated to authorised devices for its autonomous and secure execution. Relevant existing work is either inefficient or ineffective in dealing with such delegated exchange. To rectify this situation, this paper aims to propose an effective, efficient and secure solution to the delegated exchange to support the important autonomy feature offered by u-commerce systems. The proposed work includes a novel approach to symmetric-key based verifiable proxy encryption to make the exchange delegation flexible, efficient and simple to implement on resource-limited devices commonly used in u-commerce systems. This approach is then applied to design a new exchange protocol. An analysis of the protocol is also provided to confirm its security and fairness. Moreover, a comparison with related work is presented to demonstrate its much better efficiency and simplicity

A Secure Quorum Based Multi-Tag RFID System

Radio Frequency Identification (RFID) technology has been expanded to be used in different fields that need automatic identifying and verifying of tagged objects without human intervention. RFID technology offers a great advantage in comparison with barcodes by providing accurate information, ease of use and reducing of labour cost. These advantages have been utilised by using passive RFID tags. Although RFID technology can enhance the efficiency of different RFID applications systems, researchers have reported issues regarding the use of RFID technology. These issues are making the technology vulnerable to many threats in terms of security and privacy. Different RFID solutions, based on different cryptography primitives, have been developed. Most of these protocols focus on the use of passive RFID tags. However, due to the computation feasibility in passive RFID tags, these tags might be vulnerable to some of the security and privacy threats. , e.g. unauthorised reader can read the information inside tags, illegitimate tags or cloned tags can be accessed by a reader. Moreover, most consideration of reserchers is focus on single tag authentication and mostly do not consider scenarios that need multi-tag such as supply chain management and healthcare management. Secret sharing schemes have been also proposed to overcome the key management problem in supply chain management. However, secret sharing schemes have some scalability limitations when applied with high numbers of RFID tags. This work is mainly focused on solving the problem of the security and privacy in multi-tag RFID based system. In this work firstly, we studied different RFID protocols such as symmetric key authentication protocols, authentication protocols based on elliptic curve cryptography, secret sharing schemes and multi-tag authentication protocols. Secondly, we consider the significant research into the mutual authentication of passive RFID tags. Therefore, a mutual authentication scheme that is based on zero-knowledge proof have been proposed . The main object of this work is to develop an ECC- RFID based system that enables multi-RFID tags to be authenticated with one reader by using different versions of ECC public key encryption schemes. The protocol are relied on using threshold cryptosystems that operate ECC to generate secret keys then distribute and stored secret keys among multi RFID tags. Finally, we provide performance measurement for the implementation of the proposed protocols.Ministry of higher education and scientific research, Baghdad-Ira

A Practical Set-Membership Proof for Privacy-Preserving NFC Mobile Ticketing

To ensure the privacy of users in transport systems, researchers are working on new protocols providing the best security guarantees while respecting functional requirements of transport operators. In this paper, we design a secure NFC m-ticketing protocol for public transport that preserves users' anonymity and prevents transport operators from tracing their customers' trips. To this end, we introduce a new practical set-membership proof that does not require provers nor verifiers (but in a specific scenario for verifiers) to perform pairing computations. It is therefore particularly suitable for our (ticketing) setting where provers hold SIM/UICC cards that do not support such costly computations. We also propose several optimizations of Boneh-Boyen type signature schemes, which are of independent interest, increasing their performance and efficiency during NFC transactions. Our m-ticketing protocol offers greater flexibility compared to previous solutions as it enables the post-payment and the off-line validation of m-tickets. By implementing a prototype using a standard NFC SIM card, we show that it fulfils the stringent functional requirement imposed by transport operators whilst using strong security parameters. In particular, a validation can be completed in 184.25 ms when the mobile is switched on, and in 266.52 ms when the mobile is switched off or its battery is flat