Cryptography

Comprehensive Deniability Analysis of Signal Handshake Protocols: X3DH, PQXDH to Fully Post-Quantum with Deniable Ring Signatures

The Signal protocol relies on a handshake protocol, formerly X3DH and now PQXDH, to set up secure conversations. One of its privacy properties, of value to Signal, is deniability, …

Shuichi Katsumata

Bundled Authenticated Key Exchange: A Concrete Treatment of (Post-Quantum) Signal's Handshake Protocol

The Signal protocol relies on a special handshake protocol, formerly X3DH and now PQXDH, to set up secure conversations. Prior analysis of these protocols (or proposals for …

Shuichi Katsumata

Optimizations and Practicality of High-Security CSIDH

We propose higher-security parametersets of CSIDH, and present highly-optimized implementations. We measure the performance when using these parameters in TLS, and show that the …

fabio-campos

A tale of two models: formal verification of KEMTLS in Tamarin

We prove the security of KEMTLS in two Tamarin models. One mode is based on the Cremers et al. model of TLS 1.3; the other closely resembles our pen-and-paper proofs. These models …

Sofía Celi
Invited Lecture: TLS and Post-Quantum (Applied Cryptography, Radboud University) featured image

Invited Lecture: TLS and Post-Quantum (Applied Cryptography, Radboud University)

Invited lecture about TLS, its history and making TLS post quantum. I also discuss KEMTLS.

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Thom Wiggers

Building confidence in cryptographic protocols

An introduction to formal analysis and our proof of the security of KEMTLS.

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Thom Wiggers

More efficient post-quantum KEMTLS with pre-distributed public keys

We make KEMTLS more efficient in scenarios where the client already has the server's long-term public key, for example through caching or because it's pre-installed.

Peter Schwabe

Verifying Post Quantum Signatures in 8kB of RAM

In this paper, we study implementations of post-quantum signature schemes on resource-constrained devices. We focus on verification of signatures and cover NIST PQC round-3 …

ruben-gonzalez

Practically Solving LPN

We analyse the difficulty of the LPN problem in restricted memory.

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Thom Wiggers

Post-Quantum TLS without handshake signatures

We present an alternative to TLS 1.3, by authenticating using only Key-Encapsulation Mechanisms. This allows us to get rid of handshake signatures, as post-quantum signature …

Peter Schwabe