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Do Broken Hash Functions Affect the Security of Time-Stamping Schemes? [chapter]

Ahto Buldas, Sven Laur
2006 Lecture Notes in Computer Science  
We study the influence of collision-finding attacks on the security of time-stamping schemes.  ...  This does not contradict the black-box separations results because the MD structure is already a deviation from the black-box setting.  ...  in a black-box way.  ... 
doi:10.1007/11767480_4 fatcat:ayfm6ch22vg7lkmvf3cvuhcmn4

A Generalization of PGV-Hash Functions and Security Analysis in Black-Box Model [chapter]

Wonil Lee, Mridul Nandi, Palash Sarkar, Donghoon Chang, Sangjin Lee, Kouichi Sakurai
2004 Lecture Notes in Computer Science  
Here, we generalize the definition of PGV-hash function into a hash family and prove that besides the previous 20 hash functions we have 22 more collision resistant and one-way secure hash families.  ...  In [1] it was proved that 20 out of 64 PGV-hash functions [2] based on block cipher are collision resistant and one-way-secure in blackbox model of the underlying block cipher.  ...  In the new definitions we have more secure hash family (42 hash families) with respect to collision resistant and one-wayness.  ... 
doi:10.1007/978-3-540-27800-9_19 fatcat:sdbn3by2nrec7im7m33ggryqrq

Multi-collision resistance: a paradigm for keyless hash functions

Nir Bitansky, Yael Tauman Kalai, Omer Paneth
2018 Proceedings of the 50th Annual ACM SIGACT Symposium on Theory of Computing - STOC 2018  
Relying on such keyless functions, we improve on the best known round complexity for these applications.  ...  We study the notion of multi-collision resistance of hash functions -a natural relaxation of collisionresistance that only guarantees the intractability of finding many (rather than two) inputs that map  ...  We are grateful to Oded Goldreich for valuable discussions and suggestions regarding the presentation of our results.  ... 
doi:10.1145/3188745.3188870 dblp:conf/stoc/BitanskyKP18 fatcat:wkozeczwgvhz7cmwj6ev4nmuki

New Constructions for Secure Hash Functions [chapter]

William Aiello, Stuart Haber, Ramarathnam Venkatesan
1998 Lecture Notes in Computer Science  
We present new, efficient and practical schemes for construction of collision-resistant hash functions, and analyze some simple methods for combining existing hash-function designs so as to enhance their  ...  There are several collision-resistant hash functions based on des for which there are no known effective attacks, but which are too slow for most practical applications.  ...  The third author thanks Yacov Yacobi, whose questions regarding a smart-card application provided the initial interest in this problem.  ... 
doi:10.1007/3-540-69710-1_11 fatcat:swc6uitehvgkvfc7cn4nd2axbu

Analysis of the Kupyna-256 Hash Function [chapter]

Christoph Dobraunig, Maria Eichlseder, Florian Mendel
2016 Lecture Notes in Computer Science  
More specifically, we describe collision attacks on the compression function for 6 (out of 10) rounds of Kupyna-256 with an attack complexity of 2 70 , and for 7 rounds with complexity 2 125.8 .  ...  In addition, we can use the rebound attack for creating collisions for the round-reduced hash function itself.  ...  Acknowledgments The research leading to these results has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 644052 (HECTOR).  ... 
doi:10.1007/978-3-662-52993-5_29 fatcat:twmzrydsabgn3evjapjagz73vu

Cryptographic Functions from Worst-Case Complexity Assumptions [chapter]

Daniele Micciancio
2009 The LLL Algorithm  
In this paper we give a survey of the constructions and proof techniques used in this area, explain the importance of basing cryptographic functions on the worst-case complexity of lattice problems, and  ...  A remarkable feature of lattice-based cryptographic functions is that they can be proved secure (that is, hard to break on the average) based on the assumption that the underlying lattice problems are  ...  No public key encryption scheme based on an arbitrary one-way or collision resistant hash function family is known, and any such construction must necessarily be non black-box [18] .  ... 
doi:10.1007/978-3-642-02295-1_13 dblp:series/isc/Micciancio10 fatcat:2nvkrtnrnbg6fhriq5wiybvnwy

Finding Bugs in Cryptographic Hash Function Implementations

Nicky Mouha, Mohammad S. Raunak, D. Richard Kuhn, Raghu Kacker
2018 IEEE Transactions on Reliability  
We revisit the NIST hash function competition, which was used to develop the SHA-3 standard, and apply a new testing strategy to all available reference implementations.  ...  Motivated by the cryptographic properties that a hash function should satisfy, we develop four tests.  ...  Responsible disclosure: to the best of our knowledge, none of the SHA-3 candidate algorithms are used in commercial products, except for Keccak, which became the SHA-3 standard.  ... 
doi:10.1109/tr.2018.2847247 pmid:31092953 pmcid:PMC6512998 fatcat:nn3vxn5eqjg3dfu57wunfgo7fq

Functional Graphs and Their Applications in Generic Attacks on Iterated Hash Constructions

Zhenzhen Bao, Jian Guo, Lei Wang
2018 IACR Transactions on Symmetric Cryptology  
We show that the properties of the cycle search algorithm, the chain evaluation algorithm and the collision search algorithm can be described based on statistic results on the functional graph.  ...  We provide a systematic exposition of concepts of cycles, deep-iterate images, collisions and their roles in cryptanalysis of iterated hash constructions.  ...  Acknowledgments The authors would like to thank the reviewers of FSE 2018 for their detailed comments and valuable suggestions.  ... 
doi:10.46586/tosc.v2018.i1.201-253 fatcat:e5ceef32e5bsppj7dfxha3uc6y

Physical One-Way Functions

R. Pappu
2002 Science  
This dissertation introduces physical one-way functions and physical one-way hash functions as primitives for physical analogs of cryptosystems.  ...  Modern cryptography relies on algorithmic one-way functions -numerical functions which are easy to compute but very difficult to invert.  ...  I want to thank Neil Gershenfeld, my thesis advisor, for his vision, energy, enthusiasm, and  ... 
doi:10.1126/science.1074376 pmid:12242435 fatcat:okqvbdehhrga7pf53yl5uvqqcy

Functional Graphs and Their Applications in Generic Attacks on Iterated Hash Constructions

Zhenzhen Bao, Jian Guo, Lei Wang
2018 IACR Transactions on Symmetric Cryptology  
We show that the properties of the cycle search algorithm, the chain evaluation algorithm and the collision search algorithm can be described based on statistic results on the functional graph.  ...  We provide a systematic exposition of concepts of cycles, deep-iterate images, collisions and their roles in cryptanalysis of iterated hash constructions.  ...  Acknowledgments The authors would like to thank the reviewers of FSE 2018 for their detailed comments and valuable suggestions.  ... 
doi:10.13154/tosc.v2018.i1.201-253 dblp:journals/tosc/BaoGW18 fatcat:5mmdl3sfrfce7cacblfs77yzxi

The Symbiosis between Collision and Preimage Resistance [chapter]

Elena Andreeva, Martijn Stam
2011 Lecture Notes in Computer Science  
We show the implications of our result for iterated hash functions and hash chains, where the latter is related to the Winternitz one-time signature scheme.  ...  We give an in-depth analysis of existing preimage resistance notions, introduce several new notions, and establish relations and separations between the known and new preimage notions.  ...  Introduction This paper sheds fresh light on an old topic, namely how to define the basic security properties of cryptographic hash functions.  ... 
doi:10.1007/978-3-642-25516-8_10 fatcat:qzj7ukdtu5c3damznft5ubpvv4

Are PCPs Inherent in Efficient Arguments?

Guy N. Rothblum, Salil Vadhan
2010 Computational Complexity  
Acknowledgements We thank Oded Goldreich for illuminating conversations and encouragement, Luca Trevisan for an old discussion which led to the bounded-adversary pseudorandom functions we use in Section  ...  5, and the anonymous CCC 2009 reviewers for their helpful comments.  ...  We can use this intuition to transform (black-box) constructions of arguments from collision-resistant hash families (CRHFs) or one-way functions into PCPs unconditionally or under relatively mild complexity  ... 
doi:10.1007/s00037-010-0291-3 fatcat:pq6bq5px6bdbxdzdyg3yaw6udm

Are PCPs Inherent in Efficient Arguments?

Guy N. Rothblum, Salil Vadhan
2009 2009 24th Annual IEEE Conference on Computational Complexity  
Acknowledgements We thank Oded Goldreich for illuminating conversations and encouragement, Luca Trevisan for an old discussion which led to the bounded-adversary pseudorandom functions we use in Section  ...  5, and the anonymous CCC 2009 reviewers for their helpful comments.  ...  We can use this intuition to transform (black-box) constructions of arguments from collision-resistant hash families (CRHFs) or one-way functions into PCPs unconditionally or under relatively mild complexity  ... 
doi:10.1109/ccc.2009.40 dblp:conf/coco/RothblumV09 fatcat:wrr4mj5lw5f5ln7sim4m3wlbda

Verifiable Delay Functions [chapter]

Dan Boneh, Joseph Bonneau, Benedikt Bünz, Ben Fisch
2018 Lecture Notes in Computer Science  
We study the problem of building a verifiable delay function (VDF).  ...  We formalize the requirements for VDFs and present new candidate constructions that are the first to achieve an exponential gap between evaluation and verification time.  ...  We thank the CRYPTO reviewers for their helpful comments. This work was supported by NSF, a grant from ONR, the Simons Foundation, and a Google faculty fellowship.  ... 
doi:10.1007/978-3-319-96884-1_25 fatcat:dmqgme5jnzgpvhppmnnrapm5lm

Simpira v2: A Family of Efficient Permutations Using the AES Round Function [chapter]

Shay Gueron, Nicky Mouha
2016 Lecture Notes in Computer Science  
Black, J., Rogaway, P., Shrimpton, T.: Black-Box Analysis of the Block-Cipher- Based Hash-Function Constructions from PGV. In: CRYPTO 2002. LNCS, vol. 2442, pp. 320–335. Springer (2002) 15.  ...  Permutation-based hashing. Achieving 128-bit collision resistance with a 128-bit permutation has been shown to be impossible [71].  ... 
doi:10.1007/978-3-662-53887-6_4 fatcat:3wjksrkgqzgo3pg57fpdq6cffu
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