A Modular Treatment of Blind Signatures from Identification Schemes

Explore a comprehensive presentation on blind signatures derived from identification schemes in this 21-minute conference talk from EUROCRYPT 2019. Delve into the concept of one-more unforgeability and its application to anonymous compact blind signatures. Examine linear hash functions and their role in three-move identification schemes. Investigate the one-more man-in-the-middle security model and its implications for linear identification schemes. Discover the main technical ingredients, including a new forking lemma, and learn about the generic framework for linear hash functions. Understand the transition from linear identification schemes to blind signatures, with a focus on the Okamoto-Schnorr example. Conclude with a summary of key findings and explore open questions in this cutting-edge cryptographic research.

Intro
One-More Unforgeability
Motivation: Anonymous
Compact Blind Signatures
Linear Hash Functions
(Three-Move) ID Scheme
Linear Hash Function ID Scheme
One-More Man-in-the-Middle Security (OMMIM)
Security of Linear ID Scheme
Proof Ingredients
Main Technical Ingredient: New Forking Lemma
Generic Framework Linear Hash Function
From Linear ID to Blind Signatures
Example: Okamoto-Schnorr
Summary
Open Questions