Explore the security implications of truncation in pseudorandom functions (PRFs) through this 25-minute conference talk. Delve into the tight bounds for keyed sponges and truncated CBC, examining their exact PRF security. Learn about HMAC, sponge construction, and the random permutation model. Understand distinguishers and how to exploit message length. Gain insights into the intuition and challenges of proofs in this context. Discuss the key problems in the standard model, keeper pending issues, and open problems in the field of cryptography.
The Exact PRF Security of Truncation - Tight Bounds for Keyed Sponges and Truncated CBC
Overview
Syllabus
Intro
Pseudorandom functions
HMAC
Sponge Construction
Random permutation model
Distinguisher
Exploit Message Length
Truncated CBC
Intuition of Proof
Challenges of Proof
Approach
Key Problem
Standard Model
Keeper Pending
Open Problem
Taught by
TheIACR
