mailu/nginx/conf/nginx.conf

#  Basic configuration
user nginx;
worker_processes 4;
error_log /dev/stderr info;
pid /var/run/nginx.pid;
load_module "modules/ngx_mail_module.so";

events {
    worker_connections  1024;
}

http {
    # Standard HTTP configuration with slight hardening
    include /etc/nginx/mime.types;
    default_type application/octet-stream;
    access_log /dev/stdout;
    sendfile on;
    keepalive_timeout  65;
    server_tokens off;

    server {
      listen 80;

      # TLS configuration
      {% if TLS and not TLS_ERROR %}
      listen 443 ssl;

      ssl_protocols TLSv1.1 TLSv1.2;
      ssl_ciphers 'EDH+CAMELLIA:EDH+aRSA:EECDH+aRSA+AESGCM:EECDH+aRSA+SHA256:EECDH:+CAMELLIA128:+AES128:+SSLv3:!aNULL:!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!DSS:!RC4:!SEED:!IDEA:!ECDSA:kEDH:CAMELLIA128-SHA:AES128-SHA';
      ssl_prefer_server_ciphers on;
      ssl_session_timeout 5m;
      ssl_session_cache shared:SSL:50m;
      ssl_certificate {{ TLS[0] }};
      ssl_certificate_key {{ TLS[1] }};

      add_header Strict-Transport-Security max-age=15768000;

      if ($scheme = http) {
        return 301 https://$host$request_uri;
      }
      {% endif %}

      {% if TLS_FLAVOR == 'letsencrypt' %}
      location ^~ /.well-known/acme-challenge/ {
          proxy_pass http://localhost:8000;
      }
      {% endif %}

      # Actual logic
      {% if TLS_ERROR %}
      location / {
        return 403
      }
      {% else %}
      {% if WEBMAIL != 'none' %}
      location / {
        return 301 $scheme://$host/webmail/;
      }

      location /webmail {
        rewrite ^/webmail/(.*) /$1 break;
        proxy_pass http://webmail;
      }
      {% endif %}

      {% if ADMIN == 'true' %}
      location /admin {
        return 301 $scheme://$host/admin/ui;
      }
      location ~ /admin/(ui|static) {
        rewrite ^/admin/(.*) /$1 break;
        proxy_set_header X-Forwarded-Prefix /admin;
        proxy_pass http://admin;
      }
      {% endif %}

      {% if WEBDAV != 'none' %}
      location /webdav {
        rewrite ^/webdav/(.*) /$1 break;
        proxy_pass http://webdav:5232;
      }
      {% endif %}
      {% endif %}
    }
}

mail {
    server_name {{ HOSTNAMES.split(",")[0] }};
    auth_http http://{{ ADMIN_ADDRESS }}/internal/nginx;
    proxy_pass_error_message on;

    server {
      listen 25;
      protocol smtp;
      smtp_auth plain;
    }

    server {
      listen 143;
      protocol imap;
      imap_auth plain;
    }
}