Files
LEDMatrix/web_interface
ChuckBuildsandClaude Opus 5 e450a6dfb6 fix(composer): stop payload text reaching generated Python as code
Review flagged this as critical and it is: the composer builds manager.py
by interpolating payload values into source text, /api/install writes
that file into plugins_dir, and the plugin loader imports and executes
it. The ast.parse check further down rejects only *invalid* syntax, and
an injected `import os` is perfectly valid.

Confirmed against the code before this commit. A plugin name carrying a
triple quote closes the module docstring and everything after it becomes
module-level code:

    generated manager.py parses: True
    injected module-level statements: ['import os', 'PWNED = os.getuid()']

and a geometry value is interpolated verbatim, because the parameter is
annotated int but arrives as JSON:

    _compute_pos_expr('0 or __import__("os").system("id")', 'right', 'width')
      -> 'width - 0 or __import__("os").system("id")'
    generated source: x=0 or __import__("os").system("id"),

Three fixes. _safe_int coerces and optionally clamps, and
_compute_pos_expr applies it to its own argument -- which covers all
twenty-odd call sites at once rather than patching each. _rgb_expr does
the same for the eight colour interpolations, clamping channels to
0-255. Line endpoints and widths go through it too.

For the docstring, _reject_source_breaking refuses a plugin name
containing a quote, backslash or newline. Rejecting rather than escaping:
these are display names, none of that belongs in one, and a clear "Plugin
name cannot contain a double quote." beats silently mangling what the
user typed.

Verified: all three exploits now refused or neutered, and each defence
mutation-checked separately --

    coercion removed in _compute_pos_expr ->  8 failed
    docstring guard removed               ->  5 failed
    colour channels interpolated raw      -> 13 failed

87 tests, covering seven expression payloads across seven geometry
fields and three colour channels, five literal-breaking names, and the
clean case asserting a normal payload still yields no module-level
statements at all.

One aside: the first version of this test file put the exploit string
in its own module docstring, which closed it and made the file a syntax
error -- the same bug, one level up. It now describes the payload rather
than embedding it.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01STMbQE4YctTacQXfbYqKuW
2026-08-21 19:03:13 -04:00
..
2025-12-27 14:15:49 -05:00
2025-12-27 14:15:49 -05:00
2025-12-27 14:15:49 -05:00

LED Matrix Web Interface V3

Modern, production web interface for controlling the LED Matrix display.

Overview

This directory contains the active V3 web interface with the following features:

  • Real-time display preview via Server-Sent Events (SSE)
  • Plugin management and configuration
  • System monitoring and logs
  • Modern, responsive UI
  • RESTful API

Directory Structure

web_interface/
├── app.py                    # Main Flask application
├── start.py                  # Startup script
├── run.sh                    # Shell runner script
├── requirements.txt          # Python dependencies
├── blueprints/               # Flask blueprints
│   ├── api_v3.py            # API endpoints
│   └── pages_v3.py          # Page routes
├── templates/                # HTML templates
│   └── v3/
│       ├── base.html
│       ├── index.html
│       └── partials/
└── static/                   # CSS/JS assets
    └── v3/
        ├── app.css
        └── app.js

Running the Web Interface

Standalone (Development)

From the project root:

python3 web_interface/start.py

Or using the shell script:

./web_interface/run.sh

As a Service (Production)

The web interface can run as a systemd service that starts automatically based on the web_display_autostart configuration setting:

sudo systemctl start ledmatrix-web
sudo systemctl enable ledmatrix-web  # Start on boot

Accessing the Interface

Once running, access the web interface at:

Configuration

The web interface reads configuration from:

  • config/config.json - Main configuration
  • config/config_secrets.json - API keys and secrets

API Documentation

The V3 API is mounted at /api/v3/ (app.py:144). For the complete list and request/response formats, see docs/REST_API_REFERENCE.md. Quick reference for the most common endpoints:

Configuration

  • GET /api/v3/config/main - Get main configuration
  • POST /api/v3/config/main - Save main configuration
  • GET /api/v3/config/secrets - Get secrets configuration
  • POST /api/v3/config/raw/main - Save raw main config (Config Editor)
  • POST /api/v3/config/raw/secrets - Save raw secrets

Display & System Control

  • GET /api/v3/system/status - System status
  • POST /api/v3/system/action - Control display (action body: start_display, stop_display, restart_display_service, restart_web_service, git_pull, reboot_system, shutdown_system, enable_autostart, disable_autostart)
  • GET /api/v3/display/current - Current display frame
  • GET /api/v3/display/on-demand/status - On-demand status
  • POST /api/v3/display/on-demand/start - Trigger on-demand display
  • POST /api/v3/display/on-demand/stop - Clear on-demand

Plugins

  • GET /api/v3/plugins/installed - List installed plugins
  • GET /api/v3/plugins/config?plugin_id=<id> - Get plugin config
  • POST /api/v3/plugins/config - Update plugin configuration
  • GET /api/v3/plugins/schema?plugin_id=<id> - Get plugin schema
  • POST /api/v3/plugins/toggle - Enable/disable plugin
  • POST /api/v3/plugins/install - Install from registry
  • POST /api/v3/plugins/install-from-url - Install from GitHub URL
  • POST /api/v3/plugins/uninstall - Uninstall plugin
  • POST /api/v3/plugins/update - Update plugin

Plugin Store

  • GET /api/v3/plugins/store/list - List available registry plugins
  • GET /api/v3/plugins/store/github-status - GitHub authentication status
  • POST /api/v3/plugins/store/refresh - Refresh registry from GitHub

Real-time Streams (SSE)

SSE stream endpoints are defined directly on the Flask app (app.py:607-619 — includes the CSRF exemption and rate-limit hookup alongside the three route definitions), not on the api_v3 blueprint:

  • GET /api/v3/stream/stats - System statistics stream
  • GET /api/v3/stream/display - Display preview stream
  • GET /api/v3/stream/logs - Service logs stream

Development

When making changes to the web interface:

  1. Edit files in this directory
  2. Test changes by running python3 web_interface/start.py
  3. Restart the service if running: sudo systemctl restart ledmatrix-web

Notes

  • Templates and static files use the v3/ prefix to allow for future versions
  • The interface uses Flask blueprints for modular organization
  • SSE streams provide real-time updates without polling