Potato/potato/src/main.rs
2025-03-05 12:21:53 +01:00

544 lines
20 KiB
Rust

use std::{
collections::HashMap,
fmt::Debug,
fs::read_to_string,
io::{Cursor, Read, Write},
net::{Shutdown, SocketAddr, TcpListener, TcpStream},
path::PathBuf,
sync::Arc,
thread,
};
use potato_protocol::{
datatypes::{identifier::Identifier, pack::Pack, var_int::VarInt},
packet::{
Packet,
clientbound::{
self, GameEventPacket, SetChunkCacheCenterPacket,
registry_data::{
Biome, BiomeEffects, DamageType, DimensionType, PaintingVariant, RegistryData,
RegistryDataEntry, WolfVariant,
},
status_response,
},
serverbound,
},
packet_encodable::{Json, Nbt, PacketDecodeError, PacketEncodable, PacketEncodeError},
};
use thiserror::Error;
fn main() {
println!("Looking for datapacks...");
let datapacks: Vec<PathBuf> = std::fs::read_dir("run/datapacks")
.expect("Failed to read datapacks directory")
.map(|f| f.unwrap().path())
.filter(|p| p.is_dir())
.collect();
println!("Found {} datapacks", datapacks.len());
println!("Loading datapacks...");
let mut damage_types = HashMap::new();
for datapack in datapacks {
let datapack_name = datapack.file_name().unwrap().to_str().unwrap();
println!("Loading datapack: {}", datapack_name);
let path = datapack.join("data/minecraft/damage_type");
if let Ok(files) = std::fs::read_dir(path) {
for file in files {
let file = file.unwrap().path();
let name = file.file_stem().unwrap().to_str().unwrap().to_owned();
let data: DamageType = serde_json::from_str(&read_to_string(file).unwrap())
.expect("Failed to parse damage type");
damage_types.insert(Identifier::minecraft(name), data);
}
}
}
println!("Finished loading datapacks");
println!("Loaded {} damage types", damage_types.len());
let registries = Arc::new(Registries { damage_types });
let listener = TcpListener::bind("127.0.0.1:25565").unwrap();
println!("listening started, ready to accept");
for stream in listener.incoming() {
let registries = registries.clone();
match stream {
Err(e) => println!("Accept ERROR: {}", e),
// Explicit drop because of the diverging branches
Ok(stream) => drop(thread::spawn(|| handle_client(stream, registries))),
}
}
}
fn handle_client(stream: TcpStream, registries: Arc<Registries>) {
if let Ok(mut client) = ClientConnection::new(stream, registries) {
loop {
match client.read_packet() {
Ok(_) => (),
Err(e) => {
println!("[{}] Error while handling packets: {}", client.address, e);
// Make sure the connection is closed.
let _ = client.stream.shutdown(Shutdown::Both);
break;
}
}
}
}
}
#[derive(Debug)]
enum ConnectionState {
Handshaking,
Status,
Login,
Configuration,
Play,
}
struct ClientConnection {
stream: TcpStream,
address: SocketAddr,
state: ConnectionState,
recv_buffer: Vec<u8>,
registries: Arc<Registries>,
}
struct Registries {
damage_types: HashMap<Identifier, DamageType>,
}
// Max packet size is 2MB in vanilla
const RECV_BUFFER_SIZE: usize = 1024 * 1024 * 2;
#[allow(clippy::enum_variant_names)]
#[derive(Error, Debug)]
enum ConnectionError {
#[error("IO error while reading packet: {0}")]
IoError(#[from] std::io::Error),
#[error("Error while decoding packet: {0}")]
DecodeError(#[from] PacketDecodeError),
#[error("Error while encoding packet: {0}")]
EncodeError(#[from] PacketEncodeError),
#[error("Client provided invalid next state")]
InvalidNextState,
#[error("Finished")]
Finished,
}
// TODO: Need to start sending keep alive packets once we enter configuration phase
impl ClientConnection {
fn new(
stream: TcpStream,
registries: Arc<Registries>,
) -> Result<ClientConnection, std::io::Error> {
let address = stream.peer_addr()?;
Ok(ClientConnection {
state: ConnectionState::Handshaking,
address,
stream,
recv_buffer: vec![0; RECV_BUFFER_SIZE],
registries,
})
}
fn read_packet(&mut self) -> Result<(), ConnectionError> {
let packet_size: usize = VarInt::read(&mut self.stream)?.into();
self.stream
.read_exact(&mut self.recv_buffer[..packet_size])?;
self.handle_packet(packet_size)
}
fn send_packet<T: Packet>(&mut self, packet: &T) -> Result<(), ConnectionError> {
println!("[{} ({:?})] -> {:?}", self.address, self.state, packet);
let buffer = &mut Vec::new();
// Encode ID
let packet_id: i32 = match self.state {
ConnectionState::Handshaking => T::HANDSHAKE_ID,
ConnectionState::Status => T::STATUS_ID,
ConnectionState::Login => T::LOGIN_ID,
ConnectionState::Configuration => T::CONFIGURATION_ID,
ConnectionState::Play => T::PLAY_ID,
};
if packet_id == -1 {
return Err(ConnectionError::EncodeError(
PacketEncodeError::InvalidPacketId(packet_id),
));
}
let packet_id: VarInt = packet_id.into();
packet_id.encode_packet(buffer)?;
// Encode packet
packet.encode_packet(buffer)?;
// Encode length
let length_buffer = &mut Vec::new();
let length: VarInt = buffer.len().into();
length.encode_packet(length_buffer)?;
// Print raw packet bytes
// println!(
// "{:X?} ({}) {:X?} ({})",
// length_buffer,
// length_buffer.len(),
// buffer,
// buffer.len()
// );
// Send packet
self.stream.write_all(length_buffer)?;
self.stream.write_all(buffer)?;
Ok(())
}
fn handle_packet(&mut self, length: usize) -> Result<(), ConnectionError> {
match self.state {
ConnectionState::Handshaking => {
self.handle_handshaking(length)?;
}
ConnectionState::Status => {
self.handle_status(length)?;
}
ConnectionState::Login => {
self.handle_login(length)?;
}
ConnectionState::Configuration => {
self.handle_configuration(length)?;
}
ConnectionState::Play => {
self.handle_play(length)?;
}
}
Ok(())
}
fn handle_handshaking(&mut self, length: usize) -> Result<(), ConnectionError> {
let cursor = &mut Cursor::new(&self.recv_buffer[..length]);
let id = VarInt::decode_packet(cursor)?.into();
match id {
serverbound::IntentionPacket::HANDSHAKE_ID => {
let packet = serverbound::IntentionPacket::decode_packet(cursor)?;
println!("[{} (Handshaking)] <- {:?}", self.address, packet,);
self.change_state_num(packet.next_state.into())?
}
// TODO: Legacy server list ping
_ => {
println!(
"[{} (Handshaking)] <- Unknown packet id: {} with length {} data: {:X?}",
self.address,
id,
length,
&self.recv_buffer[..length]
);
}
}
Ok(())
}
fn handle_status(&mut self, length: usize) -> Result<(), ConnectionError> {
let cursor = &mut Cursor::new(&self.recv_buffer[..length]);
let id: i32 = VarInt::decode_packet(cursor)?.into();
match id {
serverbound::StatusRequestPacket::STATUS_ID => {
let packet = serverbound::StatusRequestPacket;
println!("[{} (Status)] <- {:?}", self.address, packet);
self.send_packet(&clientbound::StatusResponsePacket {
status: Json(status_response::StatusResponseData {
version: status_response::Version {
name: "Rust 1.21.4".to_owned(),
protocol: 769,
},
players: status_response::Players {
max: 500,
online: 0,
sample: vec![],
},
description: status_response::Description {
text: "A rust server!".to_owned(),
},
favicon: None,
enforce_secure_chat: false,
}),
})?;
}
serverbound::PingRequestPacket::STATUS_ID => {
let packet = serverbound::PingRequestPacket::decode_packet(cursor)?;
println!("[{} (Status)] <- {:?}", self.address, packet);
self.send_packet(&clientbound::PongResponsePacket {
timestamp: packet.timestamp,
})?;
self.stream.shutdown(Shutdown::Both)?;
return Err(ConnectionError::Finished);
}
_ => {
println!(
"[{} (Status)] <- Unknown packet id: {} with length {} data: {:X?}",
self.address,
id,
length,
&self.recv_buffer[..length]
);
}
}
Ok(())
}
fn handle_login(&mut self, length: usize) -> Result<(), ConnectionError> {
let cursor = &mut Cursor::new(&self.recv_buffer[..length]);
let id: i32 = VarInt::decode_packet(cursor)?.into();
match id {
serverbound::HelloPacket::LOGIN_ID => {
let packet = serverbound::HelloPacket::decode_packet(cursor)?;
println!("[{} (Login)] <- {:?}", self.address, packet);
self.send_packet(&clientbound::LoginFinishedPacket {
uuid: packet.uuid,
username: packet.name,
properties: vec![],
})?;
}
serverbound::LoginAcknowledgedPacket::LOGIN_ID => {
let packet = serverbound::LoginAcknowledgedPacket::decode_packet(cursor)?;
println!("[{} (Login)] <- {:?}", self.address, packet);
self.change_state(ConnectionState::Configuration)?;
self.send_packet(&clientbound::SelectKnownPacksPacket {
packs: vec![Pack {
namespace: "minecraft".to_owned(),
id: "core".to_owned(),
version: "1.21.4".to_owned(),
}],
})?;
}
_ => {
println!(
"[{} (Login)] <- Unknown packet id: {} with length {} data: {:X?}",
self.address,
id,
length,
&self.recv_buffer[..length]
);
}
}
Ok(())
}
fn handle_configuration(&mut self, length: usize) -> Result<(), ConnectionError> {
let cursor = &mut Cursor::new(&self.recv_buffer[..length]);
let id: i32 = VarInt::decode_packet(cursor)?.into();
match id {
serverbound::ClientInformationPacket::CONFIGURATION_ID => {
let packet = serverbound::ClientInformationPacket::decode_packet(cursor)?;
println!("[{} (Configuration)] <- {:?}", self.address, packet);
}
serverbound::CustomPayloadPacket::CONFIGURATION_ID => {
let packet = serverbound::CustomPayloadPacket::decode_packet(cursor)?;
println!("[{} (Configuration)] <- {:?}", self.address, packet);
}
serverbound::SelectKnownPacksPacket::CONFIGURATION_ID => {
let packet = serverbound::SelectKnownPacksPacket::decode_packet(cursor)?;
println!("[{} (Configuration)] <- {:?}", self.address, packet);
self.send_packet(&clientbound::RegistryDataPacket {
registry_id: Identifier::minecraft_str("dimension_type"),
entries: vec![RegistryDataEntry {
id: Identifier::minecraft_str("overworld"),
data: Some(Nbt(RegistryData::DimensionType(DimensionType {
fixed_time: None,
has_skylight: 1,
has_ceiling: 0,
ultrawarm: 0,
natural: 1,
coordinate_scale: 1.,
bed_works: 1,
respawn_anchor_works: 0,
min_y: 0,
height: 256,
logical_height: 256,
infiniburn: "#minecraft:infiniburn_overworld".to_owned(),
effects: "minecraft:overworld".to_owned(),
ambient_light: 0.,
piglin_safe: 1,
has_raids: 1,
monster_spawn_light_level: 0,
monster_spawn_block_light_limit: 0,
}))),
}],
})?;
self.send_packet(&clientbound::RegistryDataPacket {
registry_id: Identifier::minecraft_str("painting_variant"),
entries: vec![RegistryDataEntry {
id: Identifier::minecraft_str("backyard"),
data: Some(Nbt(RegistryData::PaintingVariant(PaintingVariant {
asset_id: "minecraft:backyard".to_owned(),
height: 2,
width: 2,
}))),
}],
})?;
self.send_packet(&clientbound::RegistryDataPacket {
registry_id: Identifier::minecraft_str("wolf_variant"),
entries: vec![RegistryDataEntry {
id: Identifier::minecraft_str("ashen"),
data: Some(Nbt(RegistryData::WolfVariant(WolfVariant {
wild_texture: "minecraft:entity/wolf/wolf_ashen".to_owned(),
tame_texture: "minecraft:entity/wolf/wolf_ashen_tame".to_owned(),
angry_texture: "minecraft:entity/wolf/wolf_ashen_angry".to_owned(),
biomes: vec![],
}))),
}],
})?;
let damage_type_registry_entries = self
.registries
.damage_types
.iter()
.map(|(key, value)| RegistryDataEntry {
id: key.clone(),
data: Some(Nbt(RegistryData::DamegeType(value.clone()))),
})
.collect();
self.send_packet(&clientbound::RegistryDataPacket {
registry_id: Identifier::minecraft_str("damage_type"),
entries: damage_type_registry_entries,
})?;
self.send_packet(&clientbound::RegistryDataPacket {
registry_id: Identifier::minecraft_str("worldgen/biome"),
entries: vec![RegistryDataEntry {
id: Identifier::minecraft_str("plains"),
data: Some(Nbt(RegistryData::Biome(Biome {
has_precipitation: 0,
temperature: 0.,
temperature_modifier: None,
downfall: 0.,
effects: BiomeEffects {
fog_color: 0,
water_color: 0,
water_fog_color: 0,
sky_color: 0,
foliage_color: None,
grass_color: None,
grass_color_modifier: None,
particle: None,
ambient_sound: None,
mood_sound: None,
additions_sound: None,
music: None,
},
}))),
}],
})?;
self.send_packet(&clientbound::FinishConfigurationPacket)?;
}
serverbound::FinishConfigurationPacket::CONFIGURATION_ID => {
let packet = serverbound::finish_configuration::FinishConfigurationPacket;
println!("[{} (Configuration)] <- {:?}", self.address, packet);
self.change_state(ConnectionState::Play)?;
self.send_packet(&clientbound::LoginPacket {
entity_id: 0,
is_hardcore: false,
dimension_names: vec![],
max_players: 500.into(),
view_distance: 10.into(),
simulation_distance: 10.into(),
reduced_debug_info: false,
enable_respawn_screen: true,
do_limited_crafting: false,
dimension_type: 0.into(),
dimension_name: Identifier::minecraft("overworld".to_owned()),
hashed_seed: 0,
game_mode: 1,
previous_game_mode: -1,
is_debug: false,
is_flat: false,
death_info: None,
portal_cooldown: 0.into(),
sea_level: 63.into(),
enforces_secure_chat: false,
})?;
self.send_packet(&GameEventPacket {
event: 13,
data: 0.,
})?;
self.send_packet(&SetChunkCacheCenterPacket {
x: 0.into(),
z: 0.into(),
})?;
}
_ => {
println!(
"[{} (Configuration)] <- Unknown packet id: {} with length {} data: {:X?}",
self.address,
id,
length,
&self.recv_buffer[..length]
);
}
}
Ok(())
}
fn handle_play(&mut self, length: usize) -> Result<(), ConnectionError> {
let cursor = &mut Cursor::new(&self.recv_buffer[..length]);
let id: i32 = VarInt::decode_packet(cursor)?.into();
match id {
serverbound::ClientTickEndPacket::PLAY_ID => {
serverbound::ClientTickEndPacket::decode_packet(cursor)?;
}
serverbound::MovePlayerPosPacket::PLAY_ID => {
let _packet = serverbound::MovePlayerPosPacket::decode_packet(cursor)?;
// println!("[{} (Play)] <- {:?}", self.address, packet);
}
serverbound::MovePlayerPosRotPacket::PLAY_ID => {
let _packet = serverbound::MovePlayerPosRotPacket::decode_packet(cursor)?;
// println!("[{} (Play)] <- {:?}", self.address, packet);
}
serverbound::MovePlayerRotPacket::PLAY_ID => {
let _packet = serverbound::MovePlayerRotPacket::decode_packet(cursor)?;
// println!("[{} (Play)] <- {:?}", self.address, packet);
}
_ => {
println!(
"[{} (Play)] <- Unknown packet id: {} with length {} data: {:X?}",
self.address,
id,
length,
&self.recv_buffer[..length]
);
}
}
Ok(())
}
fn change_state_num(&mut self, state: i32) -> Result<(), ConnectionError> {
let new_state = match state {
1 => ConnectionState::Status,
2 => ConnectionState::Login,
_ => return Err(ConnectionError::InvalidNextState),
};
self.change_state(new_state)
}
fn change_state(&mut self, new_state: ConnectionState) -> Result<(), ConnectionError> {
println!("[{}] {:?} -> {:?}", self.address, self.state, new_state);
self.state = new_state;
Ok(())
}
}