Correcting Subverted Random Oracles

Explore a presentation from Crypto 2018 on correcting subverted random oracles, delving into the vulnerabilities of hash functions and proposed solutions. Learn about hash implementation optimization, subversion attacks, chain takeover attacks, and methods to repair compromised hash functions. Examine the modeling and analysis of correcting subverted random oracles, including the rejection resampling lemma and final construction. Gain insights into preventing chain takeovers and consider open problems in this critical area of cryptography.

Syllabus

Intro
Hash Functions are Useful
Hash Implementation Can Be Optimized
Common Deployment
Subversion Attack
A Crafty Subversion
Chain Takeover Attack
The Crooked Hash
Goal: Repair Subverted Hash
Correcting Subverted ROs 1: Modeling
Rationale Behind
Correcting Subverted ROs III: Analysis
Two Challenges Remain
A New Machinery: Rejection Resampling Lemma
The Final Construction and Analysis
Preventing Chain Takeover
Reflections
Open Problems