sslh -- an applicative-level protocol multiplexer
2022-07-05, 09:30–09:50 (Europe/Paris), Amphitheater

Once upon a time, corporate firewalls started to block port 22. But we could still ssh to port 443. sslh was originally written to listen to port 443, figure out the protocol between SSH and TLS, and forward it appropriately. 15 years in the making, sslh now supports many other protocols, including TLS SNI. We will cover the main functions and configuration of the tool, both for firewall evasion (its original, malicious use), service hiding and SNI frontend (its current, benign use).

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After studying electronics and computer architecture, Yves spent a decade developing embedded software, first in a small business, then at Airbus. He then moved on to the Airbus A350 design office to work on its security. There, he practiced supplier management, systems engineering, and security requirements for systems with critical, safety-related impacts. Since then he has worked on various topics related to security, from governance to formal proofs of security properties, in several industrial domains such as aeronautics, railway and automotive.

Unsatisfied with the lack of coding in the professional life of a security architect, he finds any excuse he can to develop new tools.

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