Mosh-like per-session model, PQC on by default, real README - #1
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Replace the TCP/bincode stack with a UDP-based protocol: - 26-byte unencrypted PacketHeader (version, flags, session_id, packet_seq) for server-side routing before decryption - Protobuf envelope (prost derive macros, no protoc required) with stable field tags for forward/backward compatibility - Stream multiplexing: stream 0 = terminal PTY, streams 1+ = port forwards, each with independent sequence/replay state - 1-RTT handshake: ClientHello (plaintext) → ServerHello (hello-key encrypted); both sides derive the session key in one round trip - Cipher suite negotiation with preference list; suites in priority order: ML-KEM-1024+AES-GCM+SHA3, ML-KEM-768+AES-GCM+SHA256, X25519+AES-GCM+SHA256, X25519+ChaCha20-Poly1305+SHA256 - PQC suites (ML-KEM) gated behind the `pqc` cargo feature - Ephemeral KEM adds perfect forward secrecy on top of the SSH- bootstrapped passkey; passkey also encrypts ServerHello for implicit server authentication - SessionState now owns per-stream StreamState ring buffers; reconnect replay is per-stream Assisted-By: Claude Sonnet 4.6
The previous design had handle_client_hello spawning its own recv_packet loop, racing with the main loop on the same socket. Data packets received by the main loop were silently dropped. Replace with a proper demux architecture: - run_daemon owns the socket exclusively as the sole reader - Handshake packets spawn a handle_client_hello task as before - Data packets are routed by session_id to a per-session mpsc::Sender<ReceivedPacket> (inbound_tx), replacing the competing recv_packet call in handle_client_hello - handle_client_hello creates the (inbound_tx, inbound_rx) pair, registers inbound_tx in ActiveSession, and reads from inbound_rx - Replacing inbound_tx on reconnect closes the old Receiver, cleanly terminating the prior connection's reader task - outbound_tx replaces udp_tx: PTY reader and disconnect signals write Envelopes here; the writer task encrypts and sends them - server_last_received is now populated from actual session state rather than an empty HashMap Assisted-By: Claude Sonnet 4.6
stderr is unbuffered, so operational log messages (startup, session registration, PTY exit, timeouts) appear immediately when the daemon's stdout is redirected to a file. Error messages were already using eprintln!; this makes all messages consistent. Assisted-By: Claude Sonnet 4.6
Recipes: check-tools, build, install, test-local, log, clean. test-local covers happy path and reconnect via SIGSTOP/SIGCONT without requiring sudo or iptables. Assisted-By: Claude Sonnet 4.6
Add fmt, fmt-check, clippy, check, test, audit, build-release, and install-release recipes. Decouple build from check-tools; scope check-tools to test-local prerequisites only. Assisted-By: Claude Sonnet 4.6
Assisted-By: Claude Sonnet 4.6
Socket: $XDG_RUNTIME_DIR/etr/etrs.sock Log: $XDG_STATE_HOME/etr/etrs.log Use dirs crate for XDG lookup in etrs; create parent directory before binding the socket. Justfile derives both paths via shell expansion with XDG fallbacks. Assisted-By: Claude Sonnet 4.6
-v connection lifecycle (connect, reconnect, timeout) -vv cipher suite negotiation, session IDs, peer address -vvv per-packet trace (type, seq, size, direction) CipherSuiteId gains Display and a name() method. process_server_hello now returns the negotiated suite. etrs uses a OnceLock<u8> global so spawned tasks log without extra parameter threading. Assisted-By: Claude Sonnet 4.6
Docs: struct/method docs for Aes256GcmCipher, ChaCha20Cipher, AeadCipher, X25519KeyPair, MlKem768/1024KeyPair, StreamLifecycle variants, SessionState methods, HandshakeError variants. Tests added (+50 new tests): - crypto/aead: AEAD auth-tag verification, wrong-key, mutated ciphertext, wrong-seq, empty plaintext, seq_to_nonce uniqueness - crypto/kdf: determinism, salt/ikm/info binding, output length, SHA-256 vs SHA3-256 divergence - crypto/x25519: invalid-length error paths, key uniqueness - crypto/kyber: ML-KEM-768/1024 round-trips, wrong-ciphertext implicit rejection - transport: decode_data_packet wrong key/mutation/seq errors, decode_plaintext_packet invalid protobuf, send/recv loopback (plaintext and encrypted), truncated-header returns None - session/stream: acknowledge_up_to edge cases (empty, past end, drain all), replay_from on empty history, initial seq values - session/mod: close/apply_acks on unknown stream, last_received semantics (nothing received → 0), collect_replays with empty peer map, open_stream idempotence - handshake: MalformedPacket, UnexpectedPacket, UnsupportedSuite, last_received_seq roundtrip in both directions Assisted-By: Claude Sonnet 4.6
- Box AeadCipher::Aes256Gcm to balance variant sizes - Suppress vec_init_then_push: cfg-gated pushes can't use vec![] - Fix doc_overindented_list_items in lib.rs and protocol/mod.rs - Collapse nested if-let chains in parse_target (etr.rs) - Use is_multiple_of(2) in hex_decode (etrs.rs) - assert! instead of assert_eq!(x, true) in session tests Assisted-By: Claude Sonnet 4.6
- Replace Unix domain socket with TCP loopback (127.0.0.1:udp+1) for session registration; eliminates XDG_RUNTIME_DIR path mismatch between interactive daemon and non-interactive SSH sessions - Pass reg_port through stdin bootstrap channel instead of CLI flags, avoiding clap global-arg-after-subcommand parsing issues - Resolve hostnames via tokio::net::lookup_host instead of SocketAddr::parse to support non-IP targets like 'localhost' - Bind client UDP socket to [::]:0 for IPv6 targets, 0.0.0.0:0 for IPv4 - Default daemon bind address to [::] for dual-stack IPv4+IPv6 support - Route etr verbose logs to ~/.local/state/etr/etr.log in interactive mode to avoid corrupting raw-mode terminal display - Fix stale test asserting removed --socket CLI field Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- Fix vlog: show on stderr before raw mode, log file only during session - Set IN_RAW_MODE flag around enable/disable_raw_mode calls - AGENTS.md: require NOTES.md read on startup, update on commit/push - NOTES.md: add product vision (Mode 1 mosh-like, Mode 2 port forwarding), update known gaps, fix verbose logging description Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
etr now SSHes to the target and starts etrs on the fly — no pre-running daemon required. etrs binds a random UDP port, prints it to stdout, forks, and the child runs the session. On clean disconnect the child exits immediately. - etrs: complete rewrite as per-session binary (fork + detach) - etr: bootstrap_ssh reads PORT from SSH stdout; no reg port - ml-kem: update kyber.rs for ml-kem 0.3.2 API - handshake: generate keypair for most-preferred suite (fixes PQC) - PQC on by default; opt out with --no-default-features - justfile: test-local updated for new architecture - README: replace placeholder with real documentation - NOTES.md: reflect new architecture throughout Assisted-By: Claude Sonnet 4.6
ci.yml: trigger on feature/**, fix/**, chore/** push branches release.yml: Linux-only build (macOS/Windows untested), fix completions flag (--completions SHELL, not subcommand), simplify to single job matrix Assisted-By: Claude Sonnet 4.6
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* Fix Windows input path and terminal restore Two independent native-Windows parity fixes in the etr client. 1. Special characters no longer "eaten" (issue #54): the stdin reader used std::io::stdin().read(), which on Windows goes through Rust std's ReadConsoleW shim (UTF-16->UTF-8 + line cooking). Even in raw mode it batches input and drops non-UTF-8 bytes, which made special characters vanish (zellij keybindings needing ^g) and caused the first-line-not- echoed bug. It now reads the console input handle directly with ReadFile (read_stdin); with ENABLE_VIRTUAL_TERMINAL_INPUT on this returns the same unbatched, per-keystroke VT byte stream a Unix terminal emits. enable_vt_console also sets the console input codepage to UTF-8 (65001), saved/restored on exit, so typed multi-byte input reaches the remote as UTF-8. Adds windows-sys feature Win32_Storage_FileSystem for ReadFile. 2. Local terminal restored on exit: a remote full-screen app leaves the local terminal in alternate-screen/mouse/paste/hidden-cursor modes that disable_raw_mode does not undo, so after a hard drop or ~. the mouse wheel spewed escapes and the terminal was unusable. restore_terminal() now emits VT resets on every final-exit path: a cursor-safe part (TERM_RESET_MODES) on every exit and a screen-restoring part (TERM_RESET_SCREEN, which homes the cursor) only on unclean exits. Avoids a full RIS so scrollback is kept. Version 0.6.4 -> 0.6.5. Test count 110 -> 112 (reset-sequence regressions). Assisted-By: Claude Opus 4.8 * docs: record live Windows->WSL verification of v0.6.5 Verified end-to-end against a real Unix etrs (WSL Fedora 44): remote prompt renders, PTY command round-trips, and the client emits the cursor-safe terminal-restore sequence on clean exit (fix #2 confirmed in the live byte stream). The console input-VT path (fix #1) needs interactive keystrokes and is flagged for manual confirmation. Also notes an adjacent pre-existing gap: redirected stdin ends a remote-command session on EOF before output arrives. Assisted-By: Claude Opus 4.8 * docs: verify v0.6.5 fixes via synthesized console keystrokes Drove the live etr client with real console key events (WriteConsoleInputW) against a WSL Fedora 44 etrs. Confirms fix #1 end-to-end: Ctrl+G->0x07, arrow keys, rapid bursts and Unicode all survive the raw+VT-input ReadFile path un-eaten, and injected keystrokes reach the remote per-keystroke (remote zsh-syntax-highlighting recolours char-by-char). Confirms fix #2: cursor-safe terminal-restore sequence emitted on clean exit. Updates NOTES accordingly. Assisted-By: Claude Opus 4.8 * docs: add stdin-EOF remote-command gap to Known gaps Promote the redirected-stdin truncation note from the v0.6.5 verification footnote into the Known gaps / next steps list so it is discoverable as tracked open work, with a sketch of the ssh-parity fix (half-close stdin, keep draining PTY output). Assisted-By: Claude Opus 4.8 * docs: note just recipes fail on native Windows shells `just install` (and other bash-shebang recipes) fail from PowerShell/nushell with "could not find cygpath": just tries to translate the shebang interpreter path via cygpath, absent without Git Bash on PATH. Recorded in Known gaps with the cargo-install workaround and a sketch of a cross-shell fix. Assisted-By: Claude Opus 4.8 * Fix Windows first-line echo (#54) via reader gate The single stdin reader thread is spawned before the QUIC connect, but raw + VT-input mode is only enabled after connect. On Windows a ReadFile issued while the console is still in cooked/line mode stays line-buffered for that whole read, so the first line was held client-side until Enter ("no echo until first Enter"). The v0.6.5 ReadFile change did not fix this — it is a timing problem, not a read-mechanism one. Gate the Windows reader on a one-shot signal fired right after the first enable_raw_mode + enable_vt_console, so its first read happens in raw + VT mode and is per-keystroke. Unix is unaffected (ungated, never had the bug). Verified with an A/B console-keystroke harness that snapshots the client's stdout before Enter: pre-fix the typed first line is absent (line-buffered); with the gate it appears, echoed back per-keystroke. NOTES corrected (the earlier claim that ReadFile alone fixed #54 was wrong). Assisted-By: Claude Opus 4.8 * Fix local shell Enter broken after etr exits (Windows) enable_vt_console sets ENABLE_VIRTUAL_TERMINAL_INPUT, but crossterm's disable_raw_mode only ORs the line/echo/processed-input bits back — it never clears the VT-input flag. So after etr exited, the console was left with VT-input enabled and the local shell echoed typed characters but would not accept Enter (the VT-translated Enter wasn't seen as line submission). Capture the console's exact original input/output modes + input codepage once (capture_console_originals, before raw mode is first enabled) and restore them verbatim on every exit path (restore_console_state), which clears the leftover VT-input flag. Verified with a harness: input mode restored byte-identical (0x01f7 -> 0x01f7), VT_INPUT not left set. Pre-existing since v0.6.4; no-op on Unix. NOTES also records a related server-side gap (clean shell `exit` sometimes reconnects instead of quitting because the Disconnect races the connection close). Assisted-By: Claude Opus 4.8
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Summary
etrnow SSHes to the target and startsetrson the fly — no pre-running daemon required.etrsbinds a random UDP port, prints it to stdout, forks into the background, and exits on clean disconnect. Mirrors the mosh model.--no-default-features.etrwritesSESSION_ID_HEX/PASSKEY/TERMtoetrsstdin via SSH;etrsresponds withPORT <n>on stdout, then forks. No TCP registration port, no daemon.kyber.rsfor the new API (DecapsulationKey<P>,EncapsulationKey<P>,Kemtrait,as_slice()instead ofAsRef).feature/**,fix/**,chore/**branches.--completionsflag syntax.Test plan
just check— fmt + clippy cleancargo test— 94 tests passetr localhostconnects and shows a shell (requires passwordless SSH to localhost)🤖 Generated with Claude Code