kestrove-desktop/README.md

# kestrove-desktop

**Windows and Linux** app built on Tauri 2. The Rust side links `kestrove-core`'s `kv-ffi`
directly. The web UI only renders and never touches keys. macOS uses the native `kestrove-apple` app.

Also ships `kestrove-nmh`, the **native-messaging host** that bridges `kestrove-browser` to the app.
On a Mac, the Kestrove Mac app serves the browser extension itself (Chrome, Edge, Brave, Vivaldi, Arc,
Firefox), so this app isn't needed there; it still builds on macOS for development.

```bash
# prerequisites: rustup, Node 20+, and Tauri's OS deps (https://tauri.app/start/prerequisites/)
npm install
npm run tauri dev
npm run tauri build                   # MSI/NSIS on Windows, AppImage/deb on Linux
npm run tauri build -- --debug --bundles app   # macOS dev build (Kestrove.app)
npm run tauri icon assets/logo.png    # regenerate src-tauri/icons (placeholder logo)
(cd src-tauri && cargo clippy --all-targets -- -D warnings && cargo test)
```

The vault lives in the OS app-data dir (`vault.sqlite`, plus `pairings.json`, `settings.json` and
`secret-key`, all owner-only). Closing the window keeps Kestrove in the tray so the browser extension
keeps working; Quit is in the tray menu.

## Browser integration (docs/05)

```
extension ─ native messaging (stdio) ─▶ kestrove-nmh ─ local IPC ─▶ app (broker)
            └──────────── pairing channel: X25519 → 6 words → AES-256-GCM, end to end ───────────┘
```

The bridge is shared with the macOS app and lives in kestrove-core: `crates/kv-ipc` (framing, IPC),
`crates/kv-nmh` (the host) and `kv-ffi`'s `browser-bridge` feature (`src/bridge/`: broker, pairing
channel). This crate re-exports them under the old module names.

* **IPC** (`kv-ipc`): Unix socket `$XDG_RUNTIME_DIR/kestrove/nmh.sock` (macOS: the per-user temp
  dir), dir 0700, socket 0600, peer uid checked on both ends. Windows: `\\.\pipe\kestrove-nmh-<user>`,
  first instance only, local clients only, DACL for the current user, client token SID checked
  (compile-checked only). `KESTROVE_IPC_DIR` isolates an instance for tests.
* **Pairing** (`bridge/channel.rs`, mirrored by kestrove-browser `src/channel.ts`, shared test vectors):
  both UIs show 6 words; the user confirms in the app (needs an unlocked vault) and in the extension.
  Each connection derives a fresh session key from both sides' nonces; messages carry strict
  counters, so replay and reordering fail. `kestrove-nmh` only relays ciphertext.
* **Protocol** (`bridge/broker.rs`): `query` → identities for the origin (`items_for_url`); `fill`/`totp`
  re-check that the item matches the origin and need an unlocked vault; `save` shows a prompt in
  the app (new login or password update).
* **Native host manifests**: `native-messaging/install.sh` (Linux; macOS for development only, the Mac
  app registers its own) and `install.ps1` (Windows, HKCU registry) fill in the host path and extension ids.
* **Tests**: `cargo test` (unit tests + `tests/nmh_stdio.rs`, which drives the real `kestrove-nmh`
  over stdio through the paired channel). `examples/test-host.rs` is a headless, auto-approving
  stand-in for the app used by kestrove-browser's interop and Chrome end-to-end tests.

## Auto-lock

10 minutes idle by default (Settings), plus screen lock and sleep (`autolock.rs`). Idle time is the
system's on Windows (`GetLastInputInfo`) and macOS; on Linux it is activity inside Kestrove (UI input
and fills). Screen lock: Windows input-desktop check, Linux logind `LockedHint`, macOS session dictionary.
Sleep: a jump in the wall clock between polls.

## Sync and onboarding (docs/03, docs/10)

* **First start** offers four ways in: **Use my phone** (default: type the server URL, scan the QR on screen
  with a signed-in phone, compare the 6-digit code, then type only the master password), **Emergency Kit**
  (PDF, or a PNG/JPEG photo of its QR), **Paste setup code**, and **New account** (server URL + the server's
  `KV_SETUP_CODE`).
* **Device key** (`device_key.rs`): Windows TPM via CNG, else a DPAPI-sealed software key; Linux Secret Service,
  else a 0600 file (with a warning in Settings); macOS dev runs use the keychain. `KESTROVE_DEVICE_KEY=file`
  forces the file store.
* **Sync** (`sync.rs`) runs after unlock, after a save, every 15 minutes while unlocked, and on "Sync now".
  Lock drops all keys (core), cancels a scan-to-join and revokes an "Add a device" ticket still on screen.
  An integrity alarm shows a hard alert and a banner; syncing that vault stops.
* **Settings → Devices**: approve pending devices (compare fingerprints), remove devices, **Add a phone or
  tablet** (10-minute single-use QR; Done/Cancel revokes it) and **Approve a computer** (paste the join code a
  new computer shows under "No phone?").
* **Two instances on one machine**: `KESTROVE_DATA_DIR=/tmp/kv-b Kestrove.app/Contents/MacOS/kestrove-desktop`
  (the second one has no browser integration). `KESTROVE_DEVICE_NAME` overrides the device name.
* **Live test**: `tests/live_sync.rs` (ignored) drives three instances against a running server; see its header.

## Roadmap (M3, kestrove-spec/docs/07)
- [ ] Unlock with Windows Hello (KeyCredentialManager, TPM) and libsecret on Linux
- [x] Persistent vault (`VaultCore::open` in app data)
- [x] Sync, device approval and scan-to-join onboarding
- [x] Auto-lock on idle, screen lock and suspend
- [x] Local IPC between `kestrove-nmh` and the app, plus the pairing AEAD channel
- [x] Native-messaging manifest installers (`native-messaging/install.sh`, `install.ps1`)
- [ ] **Quick Access** global hotkey (Ctrl+Shift+Space): search, then copy or auto-type (Windows `SendInput`, X11 XTest; Wayland gets copy only)
- [ ] MSI/deb installers run the manifest installers
- [ ] Windows 11 passkey plugin provider