Reverse Proxy Configuration

RiDDiX - Matrix Synapse Panel binds to 127.0.0.1:3000 and should be served behind a reverse proxy with TLS termination.

Nginx

Basic Configuration

server {
    listen 443 ssl http2;
    server_name portal.example.com;

    ssl_certificate /etc/letsencrypt/live/portal.example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/portal.example.com/privkey.pem;

    # Security headers
    add_header Strict-Transport-Security "max-age=63072000; includeSubDomains; preload" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-Frame-Options "DENY" always;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;

    # Proxy to the app
    location / {
        proxy_pass http://127.0.0.1:3000;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";

        # Timeouts
        proxy_connect_timeout 60s;
        proxy_send_timeout 60s;
        proxy_read_timeout 60s;
    }

    # Asset uploads (increase body size for branding assets)
    client_max_body_size 5M;
}

# HTTP to HTTPS redirect
server {
    listen 80;
    server_name portal.example.com;
    return 301 https://$host$request_uri;
}

Important Headers

Header	Purpose
X-Real-IP	Client IP for rate limiting and audit logging
X-Forwarded-For	Proxy chain for IP detection
X-Forwarded-Proto	Protocol detection for secure cookies
Host	Required for correct URL generation

The application reads client IP from X-Forwarded-For first, then X-Real-IP, for rate limiting and audit log entries.

Caddy

Caddy provides automatic HTTPS with Let's Encrypt.

Caddyfile

portal.example.com {
    reverse_proxy 127.0.0.1:3000

    header {
        Strict-Transport-Security "max-age=63072000; includeSubDomains; preload"
        X-Content-Type-Options "nosniff"
        X-Frame-Options "DENY"
        Referrer-Policy "strict-origin-when-cross-origin"
    }
}

Caddy automatically:

• Obtains and renews TLS certificates
• Sets X-Forwarded-For, X-Forwarded-Proto, and X-Real-IP headers
• Handles HTTP to HTTPS redirects

Traefik

Docker Labels

If running Traefik as a Docker reverse proxy:

services:
  app:
    # ... existing config
    labels:
      - "traefik.enable=true"
      - "traefik.http.routers.portal.rule=Host(`portal.example.com`)"
      - "traefik.http.routers.portal.entrypoints=websecure"
      - "traefik.http.routers.portal.tls.certresolver=letsencrypt"
      - "traefik.http.services.portal.loadbalancer.server.port=3000"
      - "traefik.http.middlewares.portal-headers.headers.stsSeconds=63072000"
      - "traefik.http.middlewares.portal-headers.headers.stsIncludeSubdomains=true"
      - "traefik.http.middlewares.portal-headers.headers.contentTypeNosniff=true"
      - "traefik.http.middlewares.portal-headers.headers.frameDeny=true"
      - "traefik.http.routers.portal.middlewares=portal-headers"
    networks:
      - portal
      - traefik

Session Cookie and Authentication

The session cookie's Secure flag is determined by APP_URL:

• APP_URL=https://... → cookie has Secure flag → browser only sends it over HTTPS ✓
• APP_URL=http://... → cookie has no Secure flag → works over plain HTTP ✓

You can override this with COOKIE_SECURE=true or COOKIE_SECURE=false in your .env file.

danger

If your reverse proxy provides HTTPS to the browser but connects to the app via HTTP internally, set APP_URL to the public HTTPS URL. The Secure flag is about browser-to-proxy communication, not proxy-to-app.

Security Considerations

• Always use HTTPS in production. Set APP_URL to your public HTTPS URL (e.g., https://portal.example.com).
• Do not expose port 3000 to the internet. The app binds to 127.0.0.1 by default in the Docker Compose configuration.
• Ensure X-Forwarded-For or X-Real-IP headers are set by your proxy. These are used for rate limiting and audit logging. Without them, all requests appear to come from the proxy's IP.
• Set client_max_body_size (Nginx) to at least 5 MB for branding asset uploads.