This PR addresses some consistency issues that was introduced or discovered with the nodestore.
nodestore:
Now returns the node that is being put or updated when it is finished. This closes a race condition where when we read it back, we do not necessarily get the node with the given change and it ensures we get all the other updates from that batch write.
auth:
Authentication paths have been unified and simplified. It removes a lot of bad branches and ensures we only do the minimal work.
A comprehensive auth test set has been created so we do not have to run integration tests to validate auth and it has allowed us to generate test cases for all the branches we currently know of.
integration:
added a lot more tooling and checks to validate that nodes reach the expected state when they come up and down. Standardised between the different auth models. A lot of this is to support or detect issues in the changes to nodestore (races) and auth (inconsistencies after login and reaching correct state)
This PR was assisted, particularly tests, by claude code.
* feat: add verify client config for embedded DERP
* refactor: embedded DERP no longer verify clients via HTTP
- register the `headscale://` protocol in `http.DefaultTransport` to intercept network requests
- update configuration to use a single boolean option `verify_clients`
* refactor: use `http.HandlerFunc` for type definition
* refactor: some renaming and restructuring
* chore: some renaming and fix lint
* test: fix TestDERPVerifyEndpoint
- `tailscale debug derp` use random node private key
* test: add verify clients integration test for embedded DERP server
* fix: apply code review suggestions
* chore: merge upstream changes
* fix: apply code review suggestions
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Co-authored-by: Kristoffer Dalby <kristoffer@dalby.cc>
