Developer Builds Password Manager with Plausible Deniability Using Argon2id and XChaCha20-Poly1305
A Java backend developer rewrote a personal password manager originally built with Electron and React, migrating it to Tauri and Rust while redesigning its storage to support plausible deniability. The new implementation derives keys with Argon2id using a single per-install salt and encrypts files with XChaCha20-Poly1305, storing only random 32-character hex filenames without any headers or magic bytes. Multiple decoy vaults of identical size are created automatically for every user, and all files in the folder receive synchronized timestamps to eliminate metadata-based identification of the active vault. History and sync data are stored as additional encrypted files of the same format, making it impossible to distinguish real from decoy vaults from the filesystem alone. The approach mirrors VeraCrypt hidden volumes but operates on ordinary files and folders, with the explicit goal of providing deniability when a user is compelled to reveal a password.
HabrOct 18, 2026Translated from Russian