A Comprehensive Review of TLSNotary Protocol

TL;DR

This paper reviews the TLSNotary protocol, which enhances TLS security by enabling proof of data provenance using secure multi-party computation and zero-knowledge proofs, without server modifications.

Contribution

It provides a comprehensive overview of the TLSNotary protocol, detailing its cryptographic foundations and operational mechanisms, highlighting its novel approach to proof generation in TLS sessions.

Findings

TLSNotary enables proof of data provenance in TLS sessions.

The protocol leverages MPC and zero-knowledge proofs for security.

No server-side changes are required for implementation.

Abstract

Transport Layer Security (TLS) protocol is a cryptographic protocol designed to secure communication over the internet. The TLS protocol has become a fundamental in secure communication, most commonly used for securing web browsing sessions. In this work, we investigate the TLSNotary protocol, which aim to enable the Client to obtain proof of provenance for data from TLS session, while getting as much as possible from the TLS security properties. To achieve such proofs without any Server-side adjustments or permissions, the power of secure multi-party computation (MPC) together with zero knowledge proofs is used to extend the standard TLS Protocol. To make the compliacted landscape of MPC as comprehensible as possible we first introduce the cryptographic primitives required to understand the TLSNotary protocol and go through standard TLS protocol. Finally, we look at the TLSNotary protocol in detail.