fix(settings): define a 'heartbeat' route, so SecurityHeaders can handle redirected root

[smokris]

Problem

On sites where the root (/) path is redirected (e.g. when using the Social login plugin), the Admin Overview page incorrectly shows errors about security headers not being set:

Some headers are not set correctly on your instance - The X-Robots-Tag HTTP header is not set to noindex,nofollow. This is a potential security or privacy risk, as it is recommended to adjust this setting accordingly. - The X-Permitted-Cross-Domain-Policies HTTP header is not set to none. This is a potential security or privacy risk, as it is recommended to adjust this setting accordingly. For more details see the documentation ↗.

Analysis

In lib/base.php, the request path /heartbeat is handled specially by returning early, but no formal route is defined for it.

OCA\Settings\SetupChecks\SecurityHeaders calls URLGenerator::linkToRoute('heartbeat'), but the generated URL is emptystring, since there's no route defined by that name.

It then performs a request on the root (/) path (instead of the expected /heartbeat path). On sites where the root path redirects, SecurityHeaders then incorrectly analyzes the headers of the redirect, instead of analyzing the headers of the Nextcloud heartbeat page.

Proposed solution

Define a heartbeat route, so that URLGenerator::linkToRoute('heartbeat') returns /heartbeat as the SecurityHeaders test seems to expect.

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• [~] Screenshots before/after for front-end changes — N/A
• [~] Documentation (manuals or wiki) has been updated or is not required — N/A
• [~] Backports requested where applicable (ex: critical bugfixes) — N/A

[provokateurin]

It would be good to add a test to the setup checks that validates that the check now works.

[provokateurin]

Suggested change

	/** @var Router */
	private $router;
	private Router $router;

[provokateurin]

TBH I've never seen this warning on my local dev instance, can you tell me how to reproduce it?

[come-nc]

I cannot tell if adding a route like this is the right fix for this. The heartbeat short circuits a lot of things so it cannot be put in a controller.
It is still a supported URL endpoint so maybe it’s fine to add it like that?

[github-actions]

Hello there,
Thank you so much for taking the time and effort to create a pull request to our Nextcloud project.

We hope that the review process is going smooth and is helpful for you. We want to ensure your pull request is reviewed to your satisfaction. If you have a moment, our community management team would very much appreciate your feedback on your experience with this PR review process.

Your feedback is valuable to us as we continuously strive to improve our community developer experience. Please take a moment to complete our short survey by clicking on the following link: https://cloud.nextcloud.com/apps/forms/s/i9Ago4EQRZ7TWxjfmeEpPkf6

Thank you for contributing to Nextcloud and we hope to hear from you soon!

[cdammanintopix]

Hello,
Thank you for this fix.
Without it, I had the following issue in my logs:

{
  "reqId": "xxxxxxxxxx",
  "level": 1,
  "time": "2024-05-22T08:09:18+00:00",
  "remoteAddr": "xxxxxxxxxx",
  "user": "xxxxxxxxxx",
  "app": "no app in context",
  "method": "GET",
  "url": "/settings/ajax/checksetup",
  "message": "Unable to generate a URL for the named route \"heartbeat\" as such route does not exist.",
  "userAgent": "xxxxxxxxxx",
  "version": "29.0.0.19",
  "exception": {
    "Exception": "Symfony\\Component\\Routing\\Exception\\RouteNotFoundException",
    "Message": "Unable to generate a URL for the named route \"heartbeat\" as such route does not exist.",
    "Code": 0,
    "Trace": [
      {
        "file": "/var/www/html/lib/private/Route/Router.php",
        "line": 410,
        "function": "generate",
        "class": "Symfony\\Component\\Routing\\Generator\\UrlGenerator",
        "type": "->",
        "args": [
          "heartbeat",
          [],
          1
        ]
      },
      {
        "file": "/var/www/html/lib/private/Route/CachingRouter.php",
        "line": 65,
        "function": "generate",
        "class": "OC\\Route\\Router",
        "type": "->",
        "args": [
          "heartbeat",
          [],
          false
        ]
      },
      {
        "file": "/var/www/html/lib/private/URLGenerator.php",
        "line": 103,
        "function": "generate",
        "class": "OC\\Route\\CachingRouter",
        "type": "->",
        "args": [
          "heartbeat",
          []
        ]
      },
      {
        "file": "/var/www/html/apps/settings/lib/SetupChecks/SecurityHeaders.php",
        "line": 60,
        "function": "linkToRoute",
        "class": "OC\\URLGenerator",
        "type": "->",
        "args": [
          "heartbeat"
        ]
      },
      {
        "file": "/var/www/html/lib/private/SetupCheck/SetupCheckManager.php",
        "line": 51,
        "function": "run",
        "class": "OCA\\Settings\\SetupChecks\\SecurityHeaders",
        "type": "->",
        "args": []
      },
      {
        "file": "/var/www/html/apps/settings/lib/Controller/CheckSetupController.php",
        "line": 179,
        "function": "runAll",
        "class": "OC\\SetupCheck\\SetupCheckManager",
        "type": "->",
        "args": []
      },
      {
        "file": "/var/www/html/lib/private/AppFramework/Http/Dispatcher.php",
        "line": 232,
        "function": "check",
        "class": "OCA\\Settings\\Controller\\CheckSetupController",
        "type": "->",
        "args": []
      },
      {
        "file": "/var/www/html/lib/private/AppFramework/Http/Dispatcher.php",
        "line": 138,
        "function": "executeController",
        "class": "OC\\AppFramework\\Http\\Dispatcher",
        "type": "->",
        "args": [
          [
            "OCA\\Settings\\Controller\\CheckSetupController"
          ],
          "check"
        ]
      },
      {
        "file": "/var/www/html/lib/private/AppFramework/App.php",
        "line": 184,
        "function": "dispatch",
        "class": "OC\\AppFramework\\Http\\Dispatcher",
        "type": "->",
        "args": [
          [
            "OCA\\Settings\\Controller\\CheckSetupController"
          ],
          "check"
        ]
      },
      {
        "file": "/var/www/html/lib/private/Route/Router.php",
        "line": 338,
        "function": "main",
        "class": "OC\\AppFramework\\App",
        "type": "::",
        "args": [
          "OCA\\Settings\\Controller\\CheckSetupController",
          "check",
          [
            "OC\\AppFramework\\DependencyInjection\\DIContainer"
          ],
          [
            "settings.checksetup.check"
          ]
        ]
      },
      {
        "file": "/var/www/html/lib/base.php",
        "line": 1050,
        "function": "match",
        "class": "OC\\Route\\Router",
        "type": "->",
        "args": [
          "/settings/ajax/checksetup"
        ]
      },
      {
        "file": "/var/www/html/index.php",
        "line": 49,
        "function": "handleRequest",
        "class": "OC",
        "type": "::",
        "args": []
      }
    ],
    "File": "/var/www/html/3rdparty/symfony/routing/Generator/UrlGenerator.php",
    "Line": 144,
    "message": "Unable to generate a URL for the named route \"heartbeat\" as such route does not exist.",
    "exception": [],
    "CustomMessage": "Unable to generate a URL for the named route \"heartbeat\" as such route does not exist."
  },
  "id": "xxxxxxxxxx"
}

Applying this change fixed the issue.

Setup to reproduce: run the docker image as mentioned in the docs with version 29, and go to the page /settings/admin/overview