Clipcast

LAN clipboard sync: copy on one device, paste on another. Encrypted (AES-256-GCM), ordered (Lamport clock), no accounts, no cloud.

Subproject	What	Stack
desktop/	Daemon for Linux (X11/Wayland) and Windows	Rust, no async runtime
android/	Android client (8.0+, framework UI only)	Kotlin, Android SDK only

Both speak the same wire protocol: v1 UDP datagrams for short text plus a v2 TCP side channel for large text and images (announce + encrypted fetch). The cross-implementation test vectors in desktop/docs/ are the contract between them.

Security limits (read before running)

• One shared 32-byte key (base64, clipcast keygen) encrypts everything. Anyone with the key — and LAN access — can read the clipboard traffic, text and images alike.
• Keys live in plaintext: ~/.config/clipcast/key on desktop, app-private SharedPreferences on Android. Protect the machines, not just the key.
• No forward secrecy, no replay protection beyond Lamport ordering, no hardening against a malicious LAN peer beyond authentication.
• Image sizes and timing leak as metadata, and sent images sit temporarily on disk so peers can fetch them: ~/.local/state/clipcast/images/ on desktop (0600, 10-minute TTL), app-private cache on Android.
• Android applies at most ~512 KiB per text paste (Binder limit); larger transfers are refused, never partially applied. Images paste as content URIs, so the Binder limit does not apply to them (16 MiB sync limit).

Layout

clipcast/
  desktop/    Rust daemon (Cargo.toml, src/, tests/, docs/, contrib/)
  android/    Gradle project (settings.gradle.kts, app/)
  README.md   this file
  LICENSE     MIT

License

MIT — see LICENSE.