Two causes made a shared shell's PTY stream lag for non-host viewers and
then arrive "all at once":
1. Nagle's algorithm — PTY echo/keystrokes/chat are tiny frames; Nagle +
delayed-ACK (amplified by Tailscale RTT) coalesced them into bursts.
Set TCP_NODELAY on the client websocket (Plain/--no-tls path) and on
each server connection's socket (via ws.io_proto.transport).
2. Head-of-line blocking — ConnectionManager.broadcast awaited each
send() serially under a global lock, so the slowest viewer gated
delivery to everyone AND stalled the server's read of the broker's
next frame, backing the stream up. Give each connection its own
bounded outbound queue + writer task; broadcast now only enqueues and
never waits on a socket. A peer that overflows its backlog (4096) is
evicted (close 1013) and resyncs on reconnect rather than buffering
without bound or being fed a gapped terminal stream. Init snapshot is
enqueued as the guaranteed-first frame (send_state -> state_frame).
Adds tests/test_manager.py (FIFO, slow-client isolation, wedged
eviction, reconnect replacement). Also fmt-clean sbx.rs/theme.rs.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
M1: enforce the declared transfer size (clamped to MAX_SIZE) on chunk
receipt in both the Rust and Python clients — a malicious sender can no
longer grow the receive buffer unboundedly.
M2: only honor X-Forwarded-For when TRUST_PROXY is set, so a direct
client can't spoof a source IP to dodge the per-IP rate limiter.
M3: evict unverified SRP sessions after a 60s TTL on each new handshake,
preventing half-finished auths from exhausting memory.
M4: drop WS frames larger than 256 KB before they hit the store or
broadcast, bounding per-message memory and flood blast radius.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
CRITICAL fixes:
- Auto-generated self-signed TLS certs (HTTPS/WSS by default)
- Removed session_key from /srp/verify response (was sent in plaintext)
- Replaced with HMAC-SHA256 ws_token for WebSocket authentication
HIGH fixes:
- WebSocket auth now validates ws_token via hmac.compare_digest()
- /clear endpoint requires Bearer admin_token (printed at server start)
- Password no longer required as CLI arg — supports env var + getpass prompt
- Removed user_ip from Message model (no longer broadcast to clients)
MEDIUM fixes:
- Rate limiter on /srp/init and /srp/verify (10 req/min/IP)
- MessageStore capped at 1000 messages (prevents RAM DoS)
- access_log disabled (was leaking request metadata)
LOW fixes:
- Username sanitization against rich markup injection
- Dead code removed from helpers.py
All 79 tests passing.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
leetcrypt