{% extends "core.j2" %}

{% block app_specific %}
  # CryptPad serves static assets over these two domains.
  # `main_domain` is what users will enter in their address bar.
  # Privileged computation such as key management is handled in this scope
  # UI content is loaded via the `sandbox_domain`.
  # "Content Security Policy" headers prevent content loaded via the sandbox
  # from accessing privileged information.
  # These variables must be different to take advantage of CryptPad's sandboxing techniques.
  # In the event of an XSS vulnerability in CryptPad's front-end code
  # this will limit the amount of information accessible to attackers.
  set $main_domain "{{ item.ssl_name }}";
  set $sandbox_domain "sandbox.{{ item.ssl_name }}";

  # CryptPad's dynamic content (websocket traffic and encrypted blobs)
  # can be served over separate domains. Using dedicated domains (or subdomains)
  # for these purposes allows you to move them to a separate machine at a later date
  # if you find that a single machine cannot handle all of your users.
  # If you don't use dedicated domains, this can be the same as $main_domain
  # If you do, they'll be added as exceptions to any rules which block connections to remote domains.
  set $api_domain "{{ item.ssl_name }}";
  set $files_domain "{{ item.ssl_name }}";

  add_header Access-Control-Allow-Origin "*";

  set $coop '';
  if ($uri ~ ^\/sheet\/.*$) { set $coop 'same-origin'; }

  # Enable SharedArrayBuffer in Firefox (for .xlsx export)
  add_header Cross-Origin-Resource-Policy cross-origin;
  add_header Cross-Origin-Opener-Policy $coop;
  add_header Cross-Origin-Embedder-Policy require-corp;
  # any static assets loaded with "ver=" in their URL will be cached for a year
  if ($args ~ ver=) {
    set $cacheControl max-age=31536000;
  }
  if ($uri ~ ^/.*(\/|\.html)$) {
    set $cacheControl no-cache;
  }
  # Will not set any header if it is emptystring
  add_header Cache-Control $cacheControl;

  # CSS can be dynamically set inline, loaded from the same domain, or from $main_domain
  set $styleSrc   "'unsafe-inline' 'self' ${main_domain}";

  # connect-src restricts URLs which can be loaded using script interfaces
  set $connectSrc "'self' https://${main_domain} ${main_domain} https://${api_domain} blob: wss://${api_domain} ${api_domain} ${files_domain}";

  # fonts can be loaded from data-URLs or the main domain
  set $fontSrc    "'self' data: ${main_domain}";

  # images can be loaded from anywhere, though we'd like to deprecate this as it allows the use of images for tracking
  set $imgSrc     "'self' data: * blob: ${main_domain}";

  # frame-src specifies valid sources for nested browsing contexts.
  # this prevents loading any iframes from anywhere other than the sandbox domain
  set $frameSrc   "'self' ${sandbox_domain} blob:";

  # specifies valid sources for loading media using video or audio
  set $mediaSrc   "'self' data: * blob: ${main_domain}";

  # defines valid sources for webworkers and nested browser contexts
  # deprecated in favour of worker-src and frame-src
  set $childSrc   "https://${main_domain}";

  # specifies valid sources for Worker, SharedWorker, or ServiceWorker scripts.
  # supercedes child-src but is unfortunately not yet universally supported.
  set $workerSrc  "https://${main_domain}";

  # script-src specifies valid sources for javascript, including inline handlers
  set $scriptSrc  "'self' resource: ${main_domain}";

  set $unsafe 0;
  # the following assets are loaded via the sandbox domain
  # they unfortunately still require exceptions to the sandboxing to work correctly.
  if ($uri = "/sheet/inner.html") { set $unsafe 1; }
  if ($uri ~ ^\/common\/onlyoffice\/.*\/index\.html.*$) { set $unsafe 1; }

  # everything except the sandbox domain is a privileged scope, as they might be used to handle keys
  if ($host != $sandbox_domain) { set $unsafe 0; }

  # privileged contexts allow a few more rights than unprivileged contexts, though limits are still applied
  if ($unsafe) {
    set $scriptSrc "'self' 'unsafe-eval' 'unsafe-inline' resource: ${main_domain}";
  }

  # Finally, set all the rules you composed above.
  add_header Content-Security-Policy "default-src 'none'; child-src $childSrc; worker-src $workerSrc; media-src $mediaSrc; style-src $styleSrc; script-src $scriptSrc; connect-src $connectSrc; font-src $fontSrc; img-src $imgSrc; frame-src $frameSrc;";

{% endblock %}

{% block root %}
  
    root {{ nginx_www_dir }}{{ item.root }};
    index index.html;
    error_page 404 /customize.dist/404.html;

    # Finally, serve anything the above exceptions don't govern.
    try_files /www/$uri /www/$uri/index.html /customize/$uri;
{% endblock %}
{% block location%}
  location ^~ /cryptpad_websocket {
    proxy_pass http://{{ item.proxy_pass }}:3000;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header Host $host;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

    # WebSocket support (nginx 1.4)
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection upgrade;
  }

  location ^~ /customize.dist/ {
    # This is needed in order to prevent infinite recursion between /customize/ and the root
  }

  # try to load customizeable content via /customize/ and fall back to the default content
  # located at /customize.dist/
  # This is what allows you to override behaviour.
  location ^~ /customize/ {
    rewrite ^/customize/(.*)$ $1 break;
    try_files /customize/$uri /customize.dist/$uri;
  }

  # /api/config is loaded once per page load and is used to retrieve
  # the caching variable which is applied to every other resource
  # which is loaded during that session.
  location = /api/config {
    proxy_pass http://{{ item.proxy_pass }}:3000;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header Host $host;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  }

  # encrypted blobs are immutable and are thus cached for a year
  location ^~ /blob/ {
    if ($request_method = 'OPTIONS') {
      add_header 'Access-Control-Allow-Origin' '*';
      add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
      add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range';
      add_header 'Access-Control-Max-Age' 1728000;
      add_header 'Content-Type' 'application/octet-stream; charset=utf-8';
      add_header 'Content-Length' 0;
      return 204;
    }
    add_header Cache-Control max-age=31536000;
    add_header 'Access-Control-Allow-Origin' '*';
    add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
    add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range,Content-Length';
    add_header 'Access-Control-Expose-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range,Content-Length';
    try_files $uri =404;
  }

  # the "block-store" serves encrypted payloads containing users' drive keys
  # these payloads are unlocked via login credentials. They are mutable
  # and are thus never cached. They're small enough that it doesn't matter, in any case.
  location ^~ /block/ {
    add_header Cache-Control max-age=0;
    try_files $uri =404;
  }

  # This block provides an alternative means of loading content
  # otherwise only served via websocket. This is solely for debugging purposes,
  # and is thus not allowed by default.
  location ^~ /datastore/ {
    add_header Cache-Control max-age=0;
    try_files $uri =404;
  }

  # The nodejs server has some built-in forwarding rules to prevent
  # URLs like /pad from resulting in a 404. This simply adds a trailing slash
  # to a variety of applications.
  location ~ ^/(register|login|settings|user|pad|drive|poll|slide|code|whiteboard|file|media|profile|contacts|todo|filepicker|debug|kanban|sheet|support|admin|notifications|teams)$ {
    rewrite ^(.*)$ $1/ redirect;
  }
{% endblock %}