ethernet-gateway v0.6.0

Added

Configuration web server

• Optional HTTP listener that renders the same settings page the
  desktop GUI does, in a browser. Off by default; toggle in the GUI
  Server frame (new "Web Server" row between Telnet and Kermit) or
  the telnet Configuration > Server Configuration menu's
  W / B keys. Port defaults to 8080.
• Hand-rolled HTTP/1.1 on tokio (no new dependencies) implementing
  GET / (settings page), GET /logo.png (the same logo the GUI
  uses), GET /logs (2-second polled log tail), GET /serial-ports
  (live device enumeration for the dropdown refresh), and
  POST /save (config persist + optional restart).
• Per-frame Save buttons matching the GUI's three behaviors:
  Server's Save and Restart (full server restart cycles through
  main.rs exactly the way the GUI does), Serial's Save (just
  reloads serial managers via serial::restart_all_serial), and the
  plain Save on every other frame (persist only). Unknown action
  values fall back to plain Save so a hand-crafted POST with a typo
  can't accidentally restart the server.
• POST → 303 See Other → GET pattern: the save handler redirects
  to /?notice=Configuration%20saved. so a browser reload after
  submit doesn't resubmit the form. Client-side
  history.replaceState strips the ?notice= query right after
  render so the banner appears once per save instead of persisting
  across refreshes.
• Serial-port dropdown + refresh button populated server-side
  from serialport::available_ports() (the same source the GUI
  ComboBox uses); a small ↻ button next to each port re-scans via
  GET /serial-ports and rewrites both selects' options in-place
  without a full page reload. Operator's selection is preserved
  across refreshes, and a saved port that isn't currently detected
  stays visible with a (saved) suffix.
• CSS Grid Server-frame layout so the two Port: colons in each
  column line up across rows; per-port inputs sized to 6 chars (any
  valid TCP port fits) so the More button fits on row 1 alongside
  Telnet + Web Server.
• JS modal popups for the More views, plus inline confirmation
  dialogs that warn before disabling the web server or changing the
  web port — both actions break the operator's current connection.
• Connection-breaking notice included in the post-save banner
  when the operator's just-confirmed change will sever the browser
  session (e.g. "Web server port changed to 9090. Reconnect at the
  new port.").

Web auth and lockout

• HTTP Basic Auth gated on the same security_enabled flag that
  guards telnet. Uses the project's existing length-leak-resistant
  constant_time_eq from telnet.rs.
• Shared brute-force lockout map with telnet and SSH. Three
  failures across any of the three protocols trip a 5-minute IP ban
  (the same LockoutMap the telnet listener uses); failed web
  attempts respond with 429 Too Many Requests + Retry-After: 300
  once the threshold is crossed. The 429 fires before the auth
  check on every subsequent request, so a banned IP can't keep us
  busy parsing malformed POSTs either.
• Same IP-safety allowlist as telnet: when login is not required
  and disable_ip_safety is off, only private / loopback /
  link-local source IPs are accepted (and *.*.*.1 gateway
  addresses are rejected).

Web defense-in-depth

• 30-second read timeout on read_request to stop slow-loris clients
  from parking a tokio task indefinitely.
• MAX_INFLIGHT = 16 concurrent connections with a Drop-guarded
  slot release; excess connections get a 503 Service Unavailable +
  Retry-After: 5 rather than being parked behind the read timeout.
• 16 KB cap on request headers, 64 KB cap on POST body — bounded so
  a hostile peer can't drive the per-connection buffer to OOM.
• UTF-8 round-trip safe: url_decode accumulates percent-decoded
  bytes into a Vec<u8> then runs from_utf8_lossy, so values like
  weather_zip = 日本語 survive the form → config-file → form
  cycle without corruption.

Changed

Unified telnet / SSH / web credentials

• One username / password pair now covers the telnet menu, the
  SSH server, and the web configuration UI. The old per-protocol
  ssh_username / ssh_password config keys are gone. Defaults
  unchanged at admin / changeme.
• One-time migration: if the operator's egateway.conf still has
  non-default ssh_username / ssh_password values and the
  unified username / password are still at the factory defaults,
  the legacy SSH values are adopted into the unified pair on load
  (with a Note: migrating legacy ssh_username=… log line). Once
  the next save runs, the legacy keys disappear from the written
  file. If both pairs were already customized, the unified pair
  wins (the legacy SSH values are silently dropped).
• GUI Security frame collapses from two rows (separate Telnet /
  SSH credential rows) to one Login User / Pass row + a spacer
  that keeps the frame the same height as the adjacent Server frame.
• Telnet Security menu drops the S (Set SSH username) /
  W (Set SSH password) items; the remaining U / P items now
  read Set username / Set password (no more "telnet"
  qualifier). Status shows a single Username: / Password:
  pair instead of two.
• Help screens under Configuration > Security and
  Configuration > Server Configuration updated: the security
  help notes "One username/password covers telnet, SSH, and the
  web UI" and the server help describes the new W (Toggle Web) /
  B (Set Web port) keys.

GUI Server frame

• Fixed-width listener column slots so the two Port: colons line
  up between rows — the same colon-alignment the web frame gets
  from CSS Grid. The earlier hand-tuned add_space(16.0) left the
  colons at different X positions because "Telnet" / "SSH" and
  "Web Server" / "Kermit Server" have different intrinsic widths.
• More button moved up to row 1 (with Telnet + Web Server),
  mirroring the web layout.

GUI Serial Ports frame (web-side parity adjustments)

• Web Serial frame's header now carries both ports' Enabled
  checkboxes alongside per-port titles ("Serial Port A" / "Serial
  Port B"), matching the GUI's layout exactly. Per-port rows are
  now Port X: [select ▼] [↻] Baud: [...] [More...] with the More
  button kept on the same line via a no-wrap row class.

Logger

• Added a parallel non-draining snapshot(max) API alongside the
  existing drain(). The GUI keeps using drain() for its
  per-frame console accumulator; the web /logs endpoint polls
  snapshot() so the two views don't compete for log lines.