Security and Privacy - Contractor-x/bitchat GitHub Wiki

Encryption

  • Private Messages: X25519 key exchange + AES-256-GCM encryption
  • Channel Messages: Argon2id password derivation + AES-256-GCM
  • Digital Signatures: Ed25519 for message authenticity
  • Forward Secrecy: New key pairs generated each session

Privacy Features

  • No Registration: No accounts, emails, or phone numbers required
  • Ephemeral by Default: Messages exist only in device memory
  • Cover Traffic: Random delays and dummy messages prevent traffic analysis
  • Emergency Wipe: Triple-tap on logo to instantly clear all data
  • Local-First: Works completely offline, no servers involved