diff --git a/docs/example.nginx.conf b/docs/example.nginx.conf index 462b205fd..70b62b709 100644 --- a/docs/example.nginx.conf +++ b/docs/example.nginx.conf @@ -7,15 +7,29 @@ server { listen 443 ssl http2; - # XXX These two variables + # 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 "your-main-domain.com"; set $sandbox_domain "your-sandbox-domain.com"; - # The $api_domain and $files_domain are optional + # 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 "api.your-main-domain.com"; set $files_domain "files.your-main-domain.com"; - server_name $main_domain $sandbox_domain; + # nginx doesn't let you set server_name via variables, so you need to hardcode your domains here + server_name your-main-domain.com your-sandbox-domain.com; ssl_certificate /home/cryptpad/.acme.sh/your-main-domain.com/fullchain.cer; ssl_certificate_key /home/cryptpad/.acme.sh/your-main-domain.com/your-main-domain.com.key; @@ -38,33 +52,64 @@ server { index index.html; error_page 404 /customize.dist/404.html; + # any static assets loaded with "ver=" in their URL will be cached for a year if ($args ~ ver=) { set $cacheControl max-age=31536000; } # 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}"; - set $scriptSrc "'self' ${main_domain}"; + + # connect-src restricts URLs which can be loaded using script interfaces set $connectSrc "'self' https://${main_domain} wss://${main_domain} $main_domain https://${api_domain} blob:"; + + # 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' ${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 = "/pad/inner.html") { set $unsafe 1; } if ($uri = "/sheet/inner.html") { set $unsafe 1; } if ($uri = "/common/onlyoffice/web-apps/apps/spreadsheeteditor/main/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.cryptpad.info) { 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' ${main_domain}"; } - 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;"; + # 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;"; + # The nodejs process can handle all traffic whether accessed over websocket or as static assets + # We prefer to serve static content from nginx directly and to leave the API server to handle + # the dynamic content that only it can manage. This is primarily an optimization location ^~ /cryptpad_websocket { proxy_pass http://localhost:3000; proxy_set_header X-Real-IP $remote_addr; @@ -77,33 +122,20 @@ server { proxy_set_header Connection upgrade; } - location ^~ /datastore/ { - alias /home/cryptpad/office.cryptpad/data/datastore; - if ($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' 0; - add_header 'Content-Type' 'application/octet-stream; charset=utf-8'; - add_header 'Content-Length' 0; - return 204; - } - add_header Cache-Control max-age=0; - 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-Expose-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range'; - try_files $uri =404; - } - location ^~ /customize.dist/ { # This is needed in order to prevent infinite recursion between /customize/ and the root } + # try to load customizeable content via /customize/ and fall back to the default content + # located at /customize.dist/ + # This is what allows you to override behaviour. location ^~ /customize/ { rewrite ^/customize/(.*)$ $1 break; try_files /customize/$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://localhost:3000; proxy_set_header X-Real-IP $remote_addr; @@ -111,24 +143,35 @@ server { proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; } + # encrypted blobs are immutable and are thus cached for a year location ^~ /blob/ { add_header Cache-Control max-age=31536000; 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; } - location ^~ /datastore/ { - 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 ^(.*)$ $1/ redirect; } + # Finally, serve anything the above exceptions don't govern. try_files /www/$uri /www/$uri/index.html /customize/$uri; }