Building end-to-end security for Messenger
Dec 7, 2023Jon Millican, Reed Riley
Summary
This post details the rollout of end-to-end encryption (E2EE) by default for personal conversations on Messenger. It introduces the Labyrinth encrypted storage protocol for end-to-end encrypting stored messaging history between devices and describes the core cryptographic protocol for transmitting messages between clients. Key technical challenges addressed include multi-device capability, feature support (e.g., sticker library search using OHAI and Anonymous Credentials), message history management with Labyrinth, and web support for E2EE.
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