# Modeling Random Oracles Under Unpredictable Queries

@inproceedings{Farshim2016ModelingRO, title={Modeling Random Oracles Under Unpredictable Queries}, author={Pooya Farshim and Arno Mittelbach}, booktitle={FSE}, year={2016} }

In recent work, Bellare, Hoang, and Keelveedhi CRYPTO 2013 introduced a new abstraction called Universal Computational Extractors UCEs, and showed how they can replace random oracles ROs across a wide range of cryptosystems. We formulate a new framework, called Interactive Computational Extractors ICEs, that extends UCEs by viewing them as models of ROs under unpredictable aka. high-entropy queries. We overcome a number of limitations of UCEs in the new framework, and in particular prove the…

## 6 Citations

### Constant Round Maliciously Secure 2PC with Function-independent Preprocessing using LEGO

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This paper provides the first implementation of a protocol from the LEGO family that has a constant number of rounds and is optimized for the offline/online setting with function-independent preprocessing and is significantly more efficient than previous protocols when considering a high latency network.

### Context-Restricted Indifferentiability: Generalizing UCE and Implications on the Soundness of Hash-Function Constructions

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- 2017

It is proved that a non-interactive version of RO-CRI is equivalent to the UCE framework, and therefore RO- CRI leads to natural interactive generalizations of existing UCE families, and new, more fine-grained soundness properties for hash function constructions are proposed which go beyond collision-resistance and indifferentiability guarantees.

### Short Digital Signatures and ID-KEMs via Truncation Collision Resistance

- Computer Science, MathematicsASIACRYPT
- 2018

This work describes how standard- model constructions of public-key cryptosystems that previously seemed to require a programmable random oracle can be leveraged to obtain standard-model construction of identity-based key encapsulation mechanisms and digital signatures with full adaptive security.

### On Generalizations of Composable Security

- Computer Science, Mathematics
- 2020

The paradigm of provable security can be traced back to Shannon’s seminal work on the one-time pad encryption, but this work does not handily generalize to other types of schemes and flavors of security.

### Public-Seed Pseudorandom Permutations

- Computer Science, MathematicsEUROCRYPT
- 2017

This paper introduces and study the notion of a public-seed pseudorandom permutation (psPRP), which is inspired by the UCE notion by Bellare, Hoang, and Keelveedhi (CRYPTO ’13).

### Security Definitions for Hash Functions: Combining UCE and Indifferentiability

- Computer Science, MathematicsSCN
- 2018

This paper states that no hash function realizes a random oracle and no real compression function realizes an ideal one, so hash function constructions are commonly proven to be secure by showing them to be indifferentiable from arandom oracle when using an ideal compression function.

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