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Using Indistinguishability Obfuscation via UCEs [chapter]

Christina Brzuska, Arno Mittelbach
2014 Lecture Notes in Computer Science  
We provide the first standard model construction for a powerful class of Universal Computational Extractors (UCEs; Bellare et al. Crypto 2013) based on indistinguishability obfuscation.  ...  Our construction is based on puncturable PRFs (Sahai und Waters; STOC 2014) and indistinguishability obfuscation. However, our proof also relies on point obfuscation under auxiliary inputs (AIPO).  ...  Indeed, our hash-function construction only consists of a (puncturable) PRF that is obfuscated via an indistinguishability obfuscator (iO): Hash Construction: iO(PRF(k, .)) .  ... 
doi:10.1007/978-3-662-45608-8_7 fatcat:6mvjrtuypff3xanz27v2qcxirq

Universal Computational Extractors and the Superfluous Padding Assumption for Indistinguishability Obfuscation [article]

Christina Brzuska, Arno Mittelbach
2015 IACR Cryptology ePrint Archive  
We study the blow-up that occurs in indistinguishability obfuscation proof techniques due to puncturing and state the Superfluous Padding Assumption for indistinguishability obfuscation which allows us  ...  Brzuska, Farshim and Mittelbach (CRYPTO 2014) showed that a large class of UCE assumptions with computationally unpredictable sources cannot be achieved, if indistinguishability obfuscation exists.  ...  Point Obfuscation from UCEs For our construction of a UCE[S sup ∩ S q-query ] secure function (Section 5) we used indistinguishability obfuscation and composable AIPOs (for statistically unpredictable  ... 
dblp:journals/iacr/BrzuskaM15 fatcat:re77cqzwnnbwhhnvxgyrt2dmfi

Indistinguishability Obfuscation and UCEs: The Case of Computationally Unpredictable Sources [chapter]

Christina Brzuska, Pooya Farshim, Arno Mittelbach
2014 Lecture Notes in Computer Science  
We extend our attack to show that indistinguishability obfuscation is sufficient to also break the UCE security of any hash function against bounded parallel sources.  ...  We show that the existence of indistinguishability obfuscation (iO) implies (non-black-box) attacks on all the definitions that BHK proposed within their UCE framework in the original version of their  ...  Let H be a UCE[S cup ∩ S prl τ,σ,q ]-secure hash function, iO be an indistinguishability obfuscator, and let us assume once again that H.ol(λ) ≥ 2 · H.kl(λ).  ... 
doi:10.1007/978-3-662-44371-2_11 fatcat:r3cxk4frozaodgqx3mkw4r7lsy

Idea: Benchmarking Indistinguishability Obfuscation – A Candidate Implementation [chapter]

Sebastian Banescu, Martín Ochoa, Nils Kunze, Alexander Pretschner
2015 Lecture Notes in Computer Science  
We present the results of preliminary experiments implementing the Candidate Indistinguishability Obfuscation algorithm recently proposed by Garg et al. [1] .  ...  We show how different parameters of the input circuits impact the performance and the size of the obfuscated programs.  ...  As research advances towards practical fully homomorphic encryption, we expect our initial and open implementation of the candidate indistinguishability obfuscation algorithm to foster improvements by  ... 
doi:10.1007/978-3-319-15618-7_12 fatcat:wynpl6csjvdupcbztxq5456mlu

A Unified Approach to Idealized Model Separations via Indistinguishability Obfuscation [chapter]

Matthew D. Green, Jonathan Katz, Alex J. Malozemoff, Hong-Sheng Zhou
2016 Lecture Notes in Computer Science  
In this work we refute this possibility, assuming the existence of indistinguishability obfuscation. We do so in the following way.  ...  All our constructions use indistinguishability obfuscation, defined as follows. Indistinguishability obfuscation. Let {C λ } be the class of circuits of size at most λ.  ...  [11] showed that using indistinguishability obfuscation, several definitions within the UCE framework [5] (a framework which is designed to replace the random oracle model in many settings) cannot  ... 
doi:10.1007/978-3-319-44618-9_31 fatcat:4hh3ho73hnfb7gyjmc4fbgjye4

Indistinguishability Obfuscation versus Multi-bit Point Obfuscation with Auxiliary Input [chapter]

Christina Brzuska, Arno Mittelbach
2014 Lecture Notes in Computer Science  
Towards this goal, we build on techniques by Brzuska, Farshim and Mittelbach (Crypto 2014) who use indistinguishability obfuscation as a mean to attack a large class of assumptions from the Universal Computational  ...  We show that if indistinguishability obfuscation exists, then MB-AIPO does not.  ...  We obfuscate the test function via indistinguishability obfuscation and prove that it is indistinguishable from an obfuscation of the zero circuit 0, the circuit that returns 0 on all inputs.  ... 
doi:10.1007/978-3-662-45608-8_8 fatcat:b6u6guuiz5f5zarmxgs2fvhqdu

Random-Oracle Uninstantiability from Indistinguishability Obfuscation [chapter]

Christina Brzuska, Pooya Farshim, Arno Mittelbach
2015 Lecture Notes in Computer Science  
Assuming the existence of indistinguishability obfuscation (iO), we show that a number of prominent transformations in the random-oracle model are uninstantiable in the standard model.  ...  The techniques that we use to establish this result are flexible and lend themselves to a number of other transformations such as the classical Fujisaki-Okamoto transform (CRYPTO 1998) and transformations  ...  This occurs with only a negligible probability via the union bound. The proof then follows from the security of the indistinguishability obfuscator.  ... 
doi:10.1007/978-3-662-46497-7_17 fatcat:x4kztrpkyrgm7clzws2z26oic4

Two-Round Secure MPC from Indistinguishability Obfuscation [chapter]

Sanjam Garg, Craig Gentry, Shai Halevi, Mariana Raykova
2014 Lecture Notes in Computer Science  
Our main tool is indistinguishability obfuscation, for which a candidate construction was recently proposed by Garg et al.  ...  We obtain UC security with abort against static malicious adversaries, and fairness if there is an honest majority.  ...  Indistinguishability Obfuscators We will start by recalling the notion of indistinguishability obfuscation (iO) recently realized in [GGH + 13b] using candidate multilinear maps[GGH13a].  ... 
doi:10.1007/978-3-642-54242-8_4 fatcat:yryw35hxjzbevoi4jzngrefz4q

Point-Function Obfuscation: A Framework and Generic Constructions [chapter]

Mihir Bellare, Igors Stepanovs
2015 Lecture Notes in Computer Science  
We answer this in the affirmative with three generic constructions, the first based on indistinguishability obfuscation, the second on deterministic public-key encryption and the third on universal computational  ...  We end with a broader look that relates different known and possible notions of point function obfuscation to each other and to ours.  ...  We also get IND[X seup ∩ X 1 ]-secure obfuscators under the DLIN, Subgroup Indistinguishability and LWE assumptions via [16, 49, 47] .  ... 
doi:10.1007/978-3-662-49099-0_21 fatcat:sz75rzoeqvghtetoxjafx2bl3q

Contention in Cryptoland: Obfuscation, Leakage and UCE [chapter]

Mihir Bellare, Igors Stepanovs, Stefano Tessaro
2015 Lecture Notes in Computer Science  
input DH inversion) assumption, which has been used to achieve many goals including point-function obfuscation (2) iO (indistinguishability obfuscation) for all circuits cannot co-exist with key-message  ...  leakage-resilient symmetric encryption (3) iO cannot co-exist with hash functions that are UCE secure for computationally unpredictable split sources.  ...  We use the definitional framework of BST [7] which parameterizes security via classes of circuit samplers. Let Obf be an obfuscator.  ... 
doi:10.1007/978-3-662-49099-0_20 fatcat:3rrsxiqoqzbm7f5ale2fizmxfa

On the Correlation Intractability of Obfuscated Pseudorandom Functions [chapter]

Ran Canetti, Yilei Chen, Leonid Reyzin
2015 Lecture Notes in Computer Science  
We assume the existence of sub-exponentially secure indistinguishability obfuscators, puncturable pseudorandom functions, and input-hiding obfuscators for evasive circuits.  ...  For example, consider the hash function used to build the block chain in the Bitcoin protocol [Nak08].  ...  Obfuscation In this work we use indistinguishability obfuscation for all circuits, and input-hiding obfuscation for all evasive circuit collections.  ... 
doi:10.1007/978-3-662-49096-9_17 fatcat:abjanoqpvbevdmufe3ccqwhcja

Two-Round Adaptively Secure MPC from Indistinguishability Obfuscation [chapter]

Sanjam Garg, Antigoni Polychroniadou
2015 Lecture Notes in Computer Science  
In this work, using indistinguishability obfuscation, we construct the first UC two-round Multi-Party computation protocol secure against any active, adaptive adversary corrupting an arbitrary number of  ...  Indistinguishability Obfuscators We will start by recalling the notion of indistinguishability obfuscation (iO) recently realized in [GGH + 13b] using candidate multilinear maps [GGH13a] .  ...  Security is proved via a simulator provided in Section 4 and indistinguishability is argued in Section 5.  ... 
doi:10.1007/978-3-662-46497-7_24 fatcat:vzypfce6dvaj7fdfmigp2t2rbu

Adaptively Secure Two-Party Computation from Indistinguishability Obfuscation [chapter]

Ran Canetti, Shafi Goldwasser, Oxana Poburinnaya
2015 Lecture Notes in Computer Science  
It requires a global (non-programmable) reference string and is based on one way functions and general-purpose indistinguishability obfuscation with sub-exponential security, as well as augmented non-committing  ...  [STOC 02] compiler, achieves UC security with comparable efficiency parameters, but is no longer incoercible.  ...  Finally, all works use the CRS model, where the CRS contains indistinguishability-obfuscated programs.  ... 
doi:10.1007/978-3-662-46497-7_22 fatcat:4illwoapijfs7mkhi2pkdiat5a

Candidate Differing-Inputs Obfuscation from Indistinguishability Obfuscation and Auxiliary-Input Point Obfuscation [article]

Dongxue Pan, Hongda Li, Peifang Ni
2018 IACR Cryptology ePrint Archive  
It allows the obfuscation algorithm to additionally take as input the random coins used to sample the circuit pair (including the circuit to be obfuscated) and thus the obfuscation algorithm can use the  ...  Differing-inputs obfuscation (diO) , first proposed by Barak et. al. [4], provides stronger security than that provided by indistinguishability obfuscation (iO).  ...  We are grateful to Stefano Tessaro for reminding us of the relation between Canetti's strong DDH assumption [14] and the existence of VGB obfuscation for all circuits shown in [6] .  ... 
dblp:journals/iacr/PanLN18 fatcat:xqbhog4qyfgdxpmotq73xb4t4u

Implementing Resettable UC-Functionalities with Untrusted Tamper-Proof Hardware-Tokens [chapter]

Nico Döttling, Thilo Mie, Jörn Müller-Quade, Tobias Nilges
2013 Lecture Notes in Computer Science  
We show that even a simple functionality cannot be realized non-interactively using a single token.  ...  Our main result consists of two protocols, realizing functionalities that are sufficient to UC-realize any resettable two-party functionality.  ...  In this protocol the hardware token is used like a UC-commitment which is opened via the possession of a secret which is sent by the sender in the unveil phase.  ... 
doi:10.1007/978-3-642-36594-2_36 fatcat:ojklbkrgfzhebe5f6emiaewa2i
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