package net.md_5.bungee.query;
import io.netty.buffer.ByteBuf;
import io.netty.channel.AddressedEnvelope;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.socket.DatagramPacket;
import java.nio.ByteOrder;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Random;
import java.util.concurrent.TimeUnit;
import java.util.logging.Level;
import lombok.RequiredArgsConstructor;
import net.md_5.bungee.api.ProxyServer;
import net.md_5.bungee.api.config.ListenerInfo;
import net.md_5.bungee.api.connection.ProxiedPlayer;
@RequiredArgsConstructor
public class QueryHandler extends SimpleChannelInboundHandler<DatagramPacket>
{
private final ProxyServer bungee;
private final ListenerInfo listener;
/*========================================================================*/
private final Random random = new Random();
private final Map<Integer, Long> sessions = new HashMap<>();
private void writeShort(ByteBuf buf, int s)
{
buf.order( ByteOrder.LITTLE_ENDIAN ).writeShort( s );
}
private void writeNumber(ByteBuf buf, int i)
{
writeString( buf, Integer.toString( i ) );
}
private void writeString(ByteBuf buf, String s)
{
for ( char c : s.toCharArray() )
{
buf.writeByte( c );
}
buf.writeByte( 0x00 );
}
@Override
protected void channelRead0(ChannelHandlerContext ctx, DatagramPacket msg) throws Exception
{
ByteBuf in = msg.content();
if ( in.readUnsignedByte() != 0xFE || in.readUnsignedByte() != 0xFD )
{
bungee.getLogger().log( Level.WARNING, "Query - Incorrect magic!: {0}", msg.sender() );
return;
}
ByteBuf out = ctx.alloc().buffer();
AddressedEnvelope response = new DatagramPacket( out, msg.sender() );
byte type = in.readByte();
int sessionId = in.readInt();
if ( type == 0x09 )
{
out.writeByte( 0x09 );
out.writeInt( sessionId );
int challengeToken = random.nextInt();
sessions.put( challengeToken, System.currentTimeMillis() );
writeNumber( out, challengeToken );
}
if ( type == 0x00 )
{
int challengeToken = in.readInt();
Long session = sessions.get( challengeToken );
if ( session == null || System.currentTimeMillis() - session > TimeUnit.SECONDS.toMillis( 30 ) )
{
throw new IllegalStateException( "No session!" );
}
out.writeByte( 0x00 );
out.writeInt( sessionId );
if ( in.readableBytes() == 0 )
{
// Short response
writeString( out, listener.getMotd() ); // MOTD
writeString( out, "SMP" ); // Game Type
writeString( out, "BungeeCord_Proxy" ); // World Name
writeNumber( out, bungee.getOnlineCount() ); // Online Count
writeNumber( out, listener.getMaxPlayers() ); // Max Players
writeShort( out, listener.getHost().getPort() ); // Port
writeString( out, listener.getHost().getHostString() ); // IP
} else if ( in.readableBytes() == 4 )
{
// Long Response
out.writeBytes( new byte[]
{
0x73, 0x70, 0x6C, 0x69, 0x74, 0x6E, 0x75, 0x6D, 0x00, (byte) 0x80, 0x00
} );
Map<String, String> data = new LinkedHashMap<>();
data.put( "hostname", listener.getMotd() );
data.put( "gametype", "SMP" );
// Start Extra Info
data.put( "game_id", "MINECRAFT" );
data.put( "version", bungee.getGameVersion() );
data.put( "plugins", "" );
// End Extra Info
data.put( "map", "BungeeCord_Proxy" );
data.put( "numplayers", Integer.toString( bungee.getOnlineCount() ) );
data.put( "maxplayers", Integer.toString( listener.getMaxPlayers() ) );
data.put( "hostport", Integer.toString( listener.getHost().getPort() ) );
data.put( "hostip", listener.getHost().getHostString() );
for ( Map.Entry<String, String> entry : data.entrySet() )
{
writeString( out, entry.getKey() );
writeString( out, entry.getValue() );
}
out.writeByte( 0x00 ); // Null
// Padding
writeString( out, "\01player_\00" );
// Player List
for ( ProxiedPlayer p : bungee.getPlayers() )
{
writeString( out, p.getName() );
}
out.writeByte( 0x00 ); // Null
} else
{
// Error!
throw new IllegalStateException( "Invalid data request packet" );
}
}
ctx.writeAndFlush( response );
}
}