130 research outputs found
Leighton-Micali Hash-Based Signatures in the Quantum Random-Oracle Model
Digital signatures constructed solely from hash functions offer competitive signature sizes and fast signing and verifying times. Moreover, the security of hash functions against a quantum adversary is believed to be well understood. This means that hash-based signatures are strong candidates for standard use in a post-quantum world. The Leighton-Micali signature scheme (LMS) is one such scheme being considered for standardization. However all systematic analyses of LMS have only considered a classical adversary. In this work we close this gap by showing a proof of the security of LMS in the quantum random-oracle model. Our results match the bounds imposed by Grover\u27s search algorithm within a constant factor, and remain tight in the multi-user setting
On the Role of Hash-Based Signatures in Quantum-Safe Internet of Things:Current Solutions and Future Directions
The Internet of Things (IoT) is gaining ground as a pervasive presence around
us by enabling miniaturized things with computation and communication
capabilities to collect, process, analyze, and interpret information.
Consequently, trustworthy data act as fuel for applications that rely on the
data generated by these things, for critical decision-making processes, data
debugging, risk assessment, forensic analysis, and performance tuning.
Currently, secure and reliable data communication in IoT is based on public-key
cryptosystems such as Elliptic Curve Cryptosystem (ECC). Nevertheless, reliance
on the security of de-facto cryptographic primitives is at risk of being broken
by the impending quantum computers. Therefore, the transition from classical
primitives to quantum-safe primitives is indispensable to ensure the overall
security of data en route. In this paper, we investigate applications of one of
the post-quantum signatures called Hash-Based Signature (HBS) schemes for the
security of IoT devices in the quantum era. We give a succinct overview of the
evolution of HBS schemes with emphasis on their construction parameters and
associated strengths and weaknesses. Then, we outline the striking features of
HBS schemes and their significance for the IoT security in the quantum era. We
investigate the optimal selection of HBS in the IoT networks with respect to
their performance-constrained requirements, resource-constrained nature, and
design optimization objectives. In addition to ongoing standardization efforts,
we also highlight current and future research and deployment challenges along
with possible solutions. Finally, we outline the essential measures and
recommendations that must be adopted by the IoT ecosystem while preparing for
the quantum world.Comment: 18 pages, 7 tables, 7 figure
Digital Signature Schemes Based on Hash Functions
Cryptographers and security experts around the world have been awakened to the reality that one day (potentially soon) large-scale quantum computers may be available. Most of the public-key cryptosystems employed today on the Internet, in both software and in hardware, are based on number-theoretic problems which are thought to be intractable on a classical (non-quantum) computer and hence are considered secure. The most popular such examples are the RSA encryption and signature schemes, and the Elliptic Curve Diffie-Hellman (ECDH) key-exchange protocol employed widely in the SSL/TLS protocols. However, these schemes offer essentially zero security against an adversary in possession of a large-scale quantum computer. Thus, there is an urgent need to develop, analyze and implement cryptosystems and algorithms that are secure against such adversaries. It is widely believed that cryptographic hash functions are naturally resilient to attacks by a quantum adversary, and thus, signature schemes have been developed whose security relies on this belief.
The goal of this thesis is to give an overview of hash-based cryptography. We describe the most important hash-based signature schemes as well as the schemes and protocols used as subroutines within them. We give a juxtaposition between stateful and stateless signature schemes, discussing the pros and cons of both while including detailed examples. Furthermore, we detail serious flaws in the security proof for the WOTS-PRF signature scheme. This scheme had the feature that its security proof was based on minimal security assumptions, namely the pseudorandomness of the underlying function family. We explore how this flawed security argument affects the other signature schemes that utilize WOTS-PRF
A Secure Cooperative Sensing Protocol for Cognitive Radio Networks
Cognitive radio networks sense spectrum occupancy
and manage themselves to operate in unused bands without disturbing licensed users. Spectrum sensing is more accurate if jointly performed by several reliable nodes. Even though cooperative sensing is an active area of research, the secure
authentication of local sensing reports remains unsolved, thus empowering false results. This paper presents a distributed protocol based on digital signatures and hash functions, and an
analysis of its security features. The system allows determining a final sensing decision from multiple sources in a quick and secure way.Las redes de radio cognitiva detectora de espectro se las arreglan para operar en las nuevas bandas sin molestar a los usuarios con licencia. La detección de espectro es más precisa
si el conjunto está realizado por varios nodos fiables. Aunque la detección cooperativa es un área activa de investigación, la autenticación segura de informes locales de detección no ha sido resuelta, por lo tanto se pueden dar resultados falsos. Este trabajo presenta un protocolo distribuido basado en firmas digitales y en funciones hash, y un análisis de sus características de seguridad. El sistema permite determinar una decisión final de detección de múltiples fuentes de una manera rápida y segura.Les xarxes de ràdio cognitiva detectora d'espectre se les arreglen per operar en les noves bandes sense destorbar els usuaris amb llicència. La detecció d'espectre és més precisa
si el conjunt està realitzat per diversos nodes fiables. Encara que la detecció cooperativa és una àrea activa d'investigació, l'autenticació segura d'informes locals de detecció no ha estat resolta, per tant es poden donar resultats falsos. Aquest treball presenta un protocol distribuït basat en signatures digitals i en funcions hash, i una anàlisi de les seves característiques de seguretat. El sistema permet determinar una decisió final de detecció de múltiples fonts d'una manera ràpida i segura
Hash-based signatures for the internet of things
While numerous digital signature schemes exist in the literature, most real-world system rely on RSA-based signature schemes or on the digital signature algorithm (DSA), including its elliptic curve cryptography variant ECDSA. In this position paper we review a family of alternative signature schemes, based on hash functions, and we make the case for their application in Internet of Things (IoT) settings. Hash-based signatures provide postquantum security, and only make minimal security assumptions, in general requiring only a secure cryptographic hash function. This makes them extremely flexible, as they can be implemented on top of any hash function that satisfies basic security properties. Hash-based signatures also feature numerous parameters defining aspects such as signing speed and key size, that enable trade-offs in constrained environments. Simplicity of implementation and customization make hash based signatures an attractive candidate for the IoT ecosystem, which is composed of a number of diverse, constrained devices
LMS-SM3 and HSS-SM3: Instantiating Hash-based Post-Quantum Signature Schemes with SM3
We instantiate the hash-based post-quantum stateful signature schemes LMS and HSS described in RFC 8554 and NIST SP 800-208 with SM3, and report on the results of the preliminary performance test
CRUST: Cryptographic Remote Untrusted Storage without Public Keys
This paper presents CRUST, a stackable file system layer designed to provide secure file sharing over remote untrusted storage systems. CRUST is intended to be layered over insecure network file systems without changing the existing systems.
In our approach, data at rest is kept encrypted, and data integrity and access control are provided by cryptographic means. Our design completely avoids public-key cryptography operations and uses more efficient symmetric-key alternatives to achieve improved performance. As a generic and self-contained system, CRUST includes its own in-band key distribution mechanism and does not rely on any special capabilities of the server or the clients.
We have implemented CRUST as a Linux file system and shown that it performs comparably with typical underlying file systems, while providing significantly stronger security
- …