This PR implements the base foundation of the code signing and integrity check. In this PR implemented is the signing and verification logic, as well as commands to sign single apps or the core repository.
Furthermore, there is a basic implementation to display problems with the code integrity on the update screen.
Code signing basically happens the following way:
- There is a ownCloud Root Certificate authority stored `resources/codesigning/root.crt` (in this PR I also ship the private key which we obviously need to change before a release 😉). This certificate is not intended to be used for signing directly and only is used to sign new certificates.
- Using the `integrity:sign-core` and `integrity:sign-app` commands developers can sign either the core release or a single app. The core release needs to be signed with a certificate that has a CN of `core`, apps need to be signed with a certificate that either has a CN of `core` (shipped apps!) or the AppID.
- The command generates a signature.json file of the following format:
```json
{
"hashes": {
"/filename.php": "2401fed2eea6f2c1027c482a633e8e25cd46701f811e2d2c10dc213fd95fa60e350bccbbebdccc73a042b1a2799f673fbabadc783284cc288e4f1a1eacb74e3d",
"/lib/base.php": "55548cc16b457cd74241990cc9d3b72b6335f2e5f45eee95171da024087d114fcbc2effc3d5818a6d5d55f2ae960ab39fd0414d0c542b72a3b9e08eb21206dd9"
},
"certificate": "-----BEGIN CERTIFICATE-----MIIBvTCCASagAwIBAgIUPvawyqJwCwYazcv7iz16TWxfeUMwDQYJKoZIhvcNAQEF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\niG+UxI/MNcWV0uJg9S63LF8=\n-----END CERTIFICATE-----",
"signature": "U29tZVNpZ25lZERhdGFFeGFtcGxl"
}
```
`hashes` is an array of all files in the folder with their corresponding SHA512 hashes (this is actually quite cheap to calculate), the `certificate` is the certificate used for signing. It has to be issued by the ownCloud Root Authority and it's CN needs to be permitted to perform the required action. The `signature` is then a signature of the `hashes` which can be verified using the `certificate`.
Steps to do in other PRs, this is already a quite huge one:
- Add nag screen in case the code check fails to ensure that administrators are aware of this.
- Add code verification also to OCC upgrade and unify display code more.
- Add enforced code verification to apps shipped from the appstore with a level of "official"
- Add enfocrced code verification to apps shipped from the appstore that were already signed in a previous release
- Add some developer documentation on how devs can request their own certificate
- Check when installing ownCloud
- Add support for CRLs to allow revoking certificates
**Note:** The upgrade checks are only run when the instance has a defined release channel of `stable` (defined in `version.php`). If you want to test this, you need to change the channel thus and then generate the core signature:
```
➜ master git:(add-integrity-checker) ✗ ./occ integrity:sign-core --privateKey=resources/codesigning/core.key --certificate=resources/codesigning/core.crt
Successfully signed "core"
```
Then increase the version and you should see something like the following:
As you can see a failed code check will not prevent the further update. It will instead just be a notice to the admin. In a next step we will add some nag screen.
For packaging stable releases this requires the following additional steps as a last action before zipping:
1. Run `./occ integrity:sign-core` once
2. Run `./occ integrity:sign-app` _for each_ app. However, this can be simply automated using a simple foreach on the apps folder.
* if you install owncloud via package it is not
possible to skip migration tests
* this also allows to disable migration tests for
an instance by default
If no array of arrays is submitted make sure we still keep $sharedUsers
and $sharedGroups as arrays so the rest of the code keeps functioning as
it should.
* this is the preparation for some upcoming logger related changes
* also fixes an issue in the public interface where we request
an internal class as parameter
Issue report:
> Hum, well I upgraded the package then visited the web interface to
trigger the update and it failed; the UI would say there was a
possible CSRF attack and after that it'd be stuck in maintenance mode.
Tried a few times (by editing maintenance to false in owncloud.conf)
and same result each time.
That smells partially like an issue caused by our EventSource implementation, due to legacy concerns the CSRF verification happens within the EventSource handling and not when the actual endpoint is called, what happens here then is:
1. User has somehow an invalid CSRF token in session (or none at all)
2. User clicks the update button
3. Invalid CSRF token is sent to update.php - no CSRF check there => Instance gets set in maintenance mode
4. Invalid CSRF token is processed by the EventSource code => Code Execution is stopped and ownCloud is stuck in maintenance mode
I have a work-around for this problem, basically it verifies the CSRF token already in step 3 and cancels execution then. The same error will be shown to the user however he can work around it by refreshing the page – as stated by the error. I think that’s an acceptable behaviour for now: INSERT LINK
To verify this test:
1. Delete your ownCloud cookies
2. Increment the version in version.php
3. Try to upgrade
=> Before the patch: Instance shows an error, is set to upgrade mode and a refresh does not help
=> After the patch: Instance shows an error, a refresh helps though.
This is not really the best fix as a better solution would be to catch such situations when bootstrapping ownCloud, however, I don’t dare to touch base.php for this sake only, you never know what breaks then…
That said: There might be other bugs as well, especially the stacktrace is somewhat confusing but then again it installing ownCloud under /usr/share/owncloud/ and I bet that is part of the whole issue ;-)
