add basic server configuration + password protection

.gitignore

@@ -1 +1,2 @@
 /target
+server-config.json

Cargo.lock

@@ -70,6 +70,8 @@ dependencies = [
  "half",
  "parking_lot",
  "rand",
+ "serde",
+ "serde_json",
  "tokio",
 ]
 
@@ -131,6 +133,12 @@ version = "0.3.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d231dfb89cfffdbc30e7fc41579ed6066ad03abda9e567ccafae602b97ec5024"
 
+[[package]]
+name = "itoa"
+version = "1.0.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "49f1f14873335454500d59611f1cf4a4b0f786f9ac11f4312a78e4cf2566695b"
+
 [[package]]
 name = "libc"
 version = "0.2.153"
@@ -290,12 +298,49 @@ version = "0.1.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d626bb9dae77e28219937af045c257c28bfd3f69333c512553507f5f9798cb76"
 
+[[package]]
+name = "ryu"
+version = "1.0.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e86697c916019a8588c99b5fac3cead74ec0b4b819707a682fd4d23fa0ce1ba1"
+
 [[package]]
 name = "scopeguard"
 version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
+[[package]]
+name = "serde"
+version = "1.0.198"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9846a40c979031340571da2545a4e5b7c4163bdae79b301d5f86d03979451fcc"
+dependencies = [
+ "serde_derive",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.198"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e88edab869b01783ba905e7d0153f9fc1a6505a96e4ad3018011eedb838566d9"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "serde_json"
+version = "1.0.116"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3e17db7126d17feb94eb3fad46bf1a96b034e8aacbc2e775fe81505f8b0b2813"
+dependencies = [
+ "itoa",
+ "ryu",
+ "serde",
+]
+
 [[package]]
 name = "signal-hook-registry"
 version = "1.4.1"

Cargo.toml

@@ -8,4 +8,6 @@ flate2 = "1"
 half = "2"
 parking_lot = "0.12.1"
 rand = "0.8"
+serde = { version = "1", features = ["derive"] }
+serde_json = "1"
 tokio = {version = "1", features = ["full"]}

src/main.rs

@@ -1,13 +1,32 @@
-use server::Server;
+use std::path::PathBuf;
+
+use server::{config::ServerConfig, Server};
 
 mod level;
 mod packet;
 mod player;
 mod server;
 
+const CONFIG_FILE: &str = "./server-config.json";
+
 #[tokio::main]
 async fn main() -> std::io::Result<()> {
-	let mut server = Server::new().await?;
+	let config_path = PathBuf::from(CONFIG_FILE);
+	let config = if config_path.exists() {
+		serde_json::from_str(&std::fs::read_to_string(config_path)?)
+			.expect("failed to deserialize config")
+	} else {
+		let config = ServerConfig::default();
+		std::fs::write(
+			config_path,
+			serde_json::to_string_pretty(&config).expect("failed to serialize default config"),
+		)?;
+		config
+	};
+
+	println!("starting server with config: {config:#?}");
+
+	let mut server = Server::new(config).await?;
 
 	server.run().await?;
 

src/server.rs

@@ -1,3 +1,4 @@
+pub mod config;
 mod network;
 
 use std::sync::Arc;
@@ -8,6 +9,8 @@ use tokio::{net::TcpListener, sync::RwLock};
 
 use crate::{level::Level, player::Player};
 
+use self::config::ServerConfig;
+
 const DEFAULT_SERVER_SIZE: usize = 128;
 
 /// the server
@@ -28,18 +31,25 @@ pub struct ServerData {
 	pub players: Vec<Player>,
 	/// list of player ids which have been freed up
 	pub free_player_ids: Vec<i8>,
+	/// the server's config
+	pub config: ServerConfig,
 }
 
 impl Server {
 	/// creates a new server with a generated level
-	pub async fn new() -> std::io::Result<Self> {
+	pub async fn new(config: ServerConfig) -> std::io::Result<Self> {
 		println!("generating level");
 		let mut rng = rand::thread_rng();
-		let mut level = Level::new(
-			DEFAULT_SERVER_SIZE,
-			DEFAULT_SERVER_SIZE,
-			DEFAULT_SERVER_SIZE,
-		);
+		let (level_x, level_y, level_z) = if let Some(size) = &config.level_size {
+			(size.x, size.y, size.z)
+		} else {
+			(
+				DEFAULT_SERVER_SIZE,
+				DEFAULT_SERVER_SIZE,
+				DEFAULT_SERVER_SIZE,
+			)
+		};
+		let mut level = Level::new(level_x, level_y, level_z);
 		for x in 0..level.x_size {
 			for y in 0..(level.y_size / 2) {
 				for z in 0..level.z_size {
@@ -49,11 +59,11 @@ impl Server {
 		}
 		println!("done!");
 
-		Self::new_with_level(level).await
+		Self::new_with_level(config, level).await
 	}
 
 	/// creates a new server with the given level
-	pub async fn new_with_level(level: Level) -> std::io::Result<Self> {
+	pub async fn new_with_level(config: ServerConfig, level: Level) -> std::io::Result<Self> {
 		let listener = TcpListener::bind("127.0.0.1:25565").await?;
 
 		Ok(Self {
@@ -61,6 +71,7 @@ impl Server {
 				level,
 				players: Default::default(),
 				free_player_ids: Vec::new(),
+				config,
 			})),
 			listener,
 		})

src/server/config.rs

@@ -0,0 +1,39 @@
+use serde::{Deserialize, Serialize};
+
+/// configuration for the server
+#[derive(Debug, Serialize, Deserialize)]
+pub struct ServerConfig {
+	/// the server's name
+	pub name: String,
+	/// the server's motd
+	pub motd: String,
+	/// the server's password, if any
+	pub password: Option<String>,
+	/// the level's size
+	pub level_size: Option<ConfigCoordinates>,
+	/// the level's spawn point
+	pub spawn: Option<ConfigCoordinates>,
+}
+
+impl Default for ServerConfig {
+	fn default() -> Self {
+		Self {
+			name: "classic server wowie".to_string(),
+			motd: "here's the default server motd".to_string(),
+			password: None,
+			level_size: None,
+			spawn: None,
+		}
+	}
+}
+
+/// coordinates as stored in configuration
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ConfigCoordinates {
+	/// the X coordinate
+	pub x: usize,
+	/// the Y coordinate
+	pub y: usize,
+	/// the Z coordinate
+	pub z: usize,
+}

src/server/network.rs

@@ -98,12 +98,11 @@ async fn handle_stream_inner(
 						let mut reader = PacketReader::new(&read_buf);
 
 						if let Some(packet) = ClientPacket::read(packet_buf[0], &mut reader) {
-							// println!("{packet:#?}");
 							match packet {
 								ClientPacket::PlayerIdentification {
 									protocol_version,
 									username,
-									verification_key: _,
+									verification_key,
 									_unused,
 								} => {
 									if protocol_version != 0x07 {
@@ -114,6 +113,12 @@ async fn handle_stream_inner(
 
 									let mut data = data.write().await;
 
+									if let Some(password) = &data.config.password {
+										if verification_key != *password {
+											return Ok(Some("Incorrect password!".to_string()));
+										}
+									}
+
 									for player in &data.players {
 										if player.username == username {
 											return Ok(Some(
@@ -144,8 +149,8 @@ async fn handle_stream_inner(
 
 									reply_queue.push_back(ServerPacket::ServerIdentification {
 										protocol_version: 0x07,
-										server_name: "test server".to_string(),
-										server_motd: "whoaaaaaa".to_string(),
+										server_name: data.config.name.clone(),
+										server_motd: data.config.motd.clone(),
 										user_type: PlayerType::Normal,
 									});
 
@@ -156,12 +161,19 @@ async fn handle_stream_inner(
 									let username = player.username.clone();
 									data.players.push(player);
 
+									let (spawn_x, spawn_y, spawn_z) =
+										if let Some(spawn) = &data.config.spawn {
+											(spawn.x, spawn.y, spawn.z)
+										} else {
+											(16, data.level.y_size / 2 + 2, 16)
+										};
+
 									let spawn_packet = ServerPacket::SpawnPlayer {
 										player_id: *own_id,
 										player_name: username.clone(),
-										x: f16::from_f32(16.5),
-										y: f16::from_f32((data.level.y_size / 2 + 2) as f32),
-										z: f16::from_f32(16.5),
+										x: f16::from_f32(spawn_x as f32 + 0.5),
+										y: f16::from_f32(spawn_y as f32),
+										z: f16::from_f32(spawn_z as f32 + 0.5),
 										yaw: 0,
 										pitch: 0,
 									};