Suggestion: secure Nginx reverse proxy and add collabora

Docs Issues
1

Hello,
I’ve been doing some reading re securing Nginx servers and thought I’d share it with the community. I have noticed several weaknesses in the suggested configuration. The test by SSLabs gave me a low score. The following config gave me an A+ for the SSL test and no vulnerabilities by gixy. I’m using nginx v1.14.2 on Debian 10.
I’m using Collabora CODE instead of the docker, I added it to the config on the same domain. This way I only need one certificate. I enabled SSL termination in the loolwsd.xml config file of Collabora.

server {
    client_max_body_size 200M;
    server_name cells.mydomain.com;

    #Security measure to stop clickjacking attacks
    add_header X-Frame-Options "SAMEORIGIN";
    #Security measure, add HSTS
    add_header Strict-Transport-Security "max-age=31536000; includeSubdomains; preload";

    location / {
            proxy_buffering off;
            proxy_pass https://localhost:8080$request_uri;
            proxy_pass_request_headers on;
            #proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
    }

    location /ws {
            proxy_buffering off;
            proxy_pass https://localhost:8080;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
            proxy_read_timeout 86400;
    }


    # static files
    location ^~ /loleaflet {
        proxy_pass http://localhost:9980;
        proxy_set_header Host $host;
    }

    # WOPI discovery URL
    location ^~ /hosting/discovery {
        proxy_pass http://localhost:9980;
        proxy_set_header Host $host;
    }

    # Capabilities
    location ^~ /hosting/capabilities {
        proxy_pass http://localhost:9980;
        proxy_set_header Host $host;
    }

    # main websocket
    location ~ ^/lool/(.*)/ws$ {
        proxy_pass http://localhost:9980;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";
        proxy_set_header Host $host;
        proxy_read_timeout 36000s;
    }

    # download, presentation and image upload
    location ~ ^/lool {
        proxy_pass http://localhost:9980;
        proxy_set_header Host $host;
    }

    # Admin Console websocket
    location ^~ /lool/adminws {
        proxy_pass http://localhost:9980;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";
        proxy_set_header Host $host;
        proxy_read_timeout 36000s;
    }

    error_log /var/log/nginx/cells-proxy-error.log;
    access_log /var/log/nginx/cells-proxy-access.log;


    listen [::]:443 ssl;
    listen 443 ssl;
    ssl_certificate     /etc/letsencrypt/live/cells.mydomain.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/cells.mydomain.com/privkey.pem;
    ssl_protocols       TLSv1.2;
    ssl_ciphers         HIGH:!aNULL:!MD5;
    #Generated using openssl dhparam -out dhparam.pem 4096
    #Fixes weak Diffie-Hellman keys
    ssl_dhparam         /etc/ssl/certs/dhparam.pem;

}

server {
    if ($host = cells.mydomain.com) {
        return 301 https://$host$request_uri;
    }

    listen 80;
    listen [::]:80;
    server_name cells.mydomain.com;
    return 404;
}
server {
    listen 33060 ssl http2;
    listen [::]:33060 ssl http2;
  ssl_certificate     /etc/letsencrypt/live/cells.mydomain.com/fullchain.pem;
  ssl_certificate_key /etc/letsencrypt/live/cells.mydomain.com/privkey.pem;
  ssl_protocols       TLSv1.2;
  ssl_ciphers         HIGH:!aNULL:!MD5;
  keepalive_timeout 600s;

    location / {
        grpc_pass grpcs://localhost:33060;
    }

  error_log /var/log/nginx/proxy-grpc-error.log;
  access_log /var/log/nginx/proxy-grpc-access.log;
}

I followed quite a few articles and guides so I can’t credit them all, and fortunately Collabora has this useful page about configing nginx.

I hope it’ll be useful for someone

2

Hello @benw ,

Thank you for your suggestion, we will take a look, test and update the documentation accordingly.