As documented in the Apache NiFi Wiki Feature Roadmap (Security), I have wanted to implement for some time a feature where the administrator of a NiFi instance does not have to know the intricate details of TLS configuration in order to deploy a secure instance. What I propose is the following:
- The administrator can set the TLS security settings to high, medium, and low
- These settings have accompanying descriptions explaining that "high means most secure (with lower backwards compatibility)", "medium tries to strike a balance between security and compatibility", and "low allows for more widespread legacy compatibility with less emphasis on security".
- The cipher suite lists and protocol versions for each would be downloaded from the Mozilla TLS Observatory, which publishes updated definitions for each of "modern", "intermediate", and "legacy" options at initial startup and at regular intervals.
- For deployments in an airgapped or other environment without desired connectivity to this service, or where the source is preferred to be controlled by an organizational entity, an alternate service endpoint can be configured (for proof of concept, this could even be the NiFi instance itself reading a file from disk and returning JSON over an HTTP endpoint).
- When a new definition is received or selected, the application framework would either:
- Restart the Jetty server automatically in a pre-configured timeframe
- Wait for all queues to empty and then restart
- Provide a visual alert (bulletin, etc.) that new definitions were received and a manual restart is required
- This setting could be set in a variety of ways:
- Directly in nifi.properties before the first application launch
- Given as an argument to an enhanced TLS Toolkit (i.e. ./bin/tls-toolkit.sh standalone ... -S high) and then the resulting nifi.properties placed in the correct location
- Through a UI configuration option (this would need to be restricted to the appropriate NiFi permissions and would require a Jetty server restart)
- The definitions would "grow" with the ecosystem (i.e. as a new vulnerability is discovered or a new protocol version/cipher suite is made available, it is automatically added/removed from the definition, thus continually improving the security stance of the application without requiring active monitoring and input from an administrator)
|Create service to retrieve TLS configurations from remote endpoint||Open||Unassigned|
|Create JSON reader, writer, signer, and verifier||Open||Unassigned|
|Configure JettyServer with custom TLS protocols and cipher suites||In Progress|