Proxy Support

[Tert0]

This PR adds Proxy Support.

TODO

• Velocity Support
• Bungeecord Support
• Add Plugin Message API (Client Event)
• VELOCITY_MODERN_FORWARDING_WITH_KEY_V2

Closes #39

[rj00a]

Looking good so far!

[rj00a]

Where did you get your information on how the proxies work?

[Tert0]

I've read the source code of Velocity and the PaperMC Implementation

[rj00a]

Reviewing this now. Will be pushing changes tomorrow.

[rj00a]

Changes I've Made

• Cleaned up documentation in config.rs.
• The handle_login function was quite large so I moved all that logic into a new submodule.
• Removed the proxy module since there wasn't much there.
• Removed incorrect uses of unwrap and expect. (If we panic it would bring down the whole server).
• Used existing types to parse where applicable.
• Set the IP address of the client in the BungeeCord login procedure.
• Removed Velocity version check. Let me know if it was wrong to remove this.
• More descriptive error messages.
• Many stylistic adjustments and optimizations.

Issues to Resolve Before Merging

• The second element of the NUL-delimited list in the BungeeCord procedure appears to be the client's IP address, but I'm not certain. Can you confirm?
• VELOCITY_MODERN_FORWARDING_WITH_KEY_V2 is unimplemented. Probably not a blocker for merging. Not sure how important it is.
• After logging in with ConnectionMode::BungeeCord or ConnectionMode::Velocity, the client fails to fully join and is disconnected with the following error. This problem exists before and after my changes.

[Tert0]

• The second element of the NUL-delimited list in the BungeeCord procedure appears to be the client's IP address, but I'm not certain. Can you confirm?

I think it's the IP you have used to conntect to the server. (e.g. 127.0.0.1 or localhost)

• VELOCITY_MODERN_FORWARDING_WITH_KEY_V2 is unimplemented. Probably not a blocker for merging. Not sure how important it is.

I think i forget to Push These changes, so i'll push them later.

[rj00a]

I think it's the IP you have used to conntect to the server. (e.g. 127.0.0.1 or localhost)

When I tried it, the first element was localhost while the second was 127.0.0.1. So I think the first is the address the player used to connect (possibly requiring DNS lookup) while the second is the address of the connecting player. Correct me if I'm wrong.

[rj00a]

I'm going to go ahead and merge what we have here to avoid conflicts.