/*
* This file is part of LanternServer, licensed under the MIT License (MIT).
*
* Copyright (c) LanternPowered <https://www.lanternpowered.org>
* Copyright (c) SpongePowered <https://www.spongepowered.org>
* Copyright (c) contributors
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the Software), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
/*
* Copyright (c) 2011-2014 Glowstone - Tad Hardesty
* Copyright (c) 2010-2011 Lightstone - Graham Edgecombe
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package org.lanternpowered.server.network.rcon;
import io.netty.buffer.ByteBuf;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.util.AttributeKey;
import org.lanternpowered.server.game.Lantern;
import org.spongepowered.api.Sponge;
import org.spongepowered.api.event.SpongeEventFactory;
import org.spongepowered.api.event.cause.Cause;
import org.spongepowered.api.event.network.rcon.RconConnectionEvent;
import java.nio.charset.StandardCharsets;
public class RconHandler extends SimpleChannelInboundHandler<ByteBuf> {
private static final AttributeKey<RconSource> SOURCE = AttributeKey.valueOf("rcon-source");
private static final byte FAILURE = -1;
private static final byte TYPE_RESPONSE = 0;
private static final byte TYPE_COMMAND = 2;
private static final byte TYPE_LOGIN = 3;
private final RconServer server;
private final String password;
public RconHandler(RconServer server, String password) {
this.password = password;
this.server = server;
}
@Override
protected void channelRead0(ChannelHandlerContext ctx, ByteBuf buf) throws Exception {
if (buf.readableBytes() < 8) {
return;
}
int requestId = buf.readIntLE();
int type = buf.readIntLE();
byte[] payloadData = new byte[buf.readableBytes() - 2];
buf.readBytes(payloadData);
String payload = new String(payloadData, StandardCharsets.UTF_8);
// Two byte padding
buf.readBytes(2);
if (type == TYPE_LOGIN) {
handleLogin(ctx, payload, this.password, requestId);
} else if (type == TYPE_COMMAND) {
handleCommand(ctx, payload, requestId);
} else {
sendLargeResponse(ctx, requestId, "Unknown request " + Integer.toHexString(type));
}
}
@Override
public void channelActive(ChannelHandlerContext ctx) {
Channel channel = ctx.channel();
RconSource source = this.server.newSource(channel);
if (!channel.attr(SOURCE).compareAndSet(null, source)) {
throw new IllegalStateException("Rcon source may not be set more than once!");
}
this.server.onChannelActive(source);
RconConnectionEvent.Connect event = SpongeEventFactory.createRconConnectionEventConnect(Cause.source(source).build(), source);
Sponge.getEventManager().post(event);
}
@Override
public void channelInactive(ChannelHandlerContext ctx) {
Channel channel = ctx.channel();
RconSource source = channel.attr(SOURCE).getAndRemove();
RconConnectionEvent.Disconnect event = SpongeEventFactory.createRconConnectionEventDisconnect(Cause.source(source).build(), source);
Sponge.getEventManager().post(event);
this.server.onChannelInactive(source);
}
private static void handleLogin(ChannelHandlerContext ctx, String payload, String password, int requestId) {
RconSource source = ctx.channel().attr(SOURCE).get();
if (password.equals(payload)) {
RconConnectionEvent.Login event = SpongeEventFactory.createRconConnectionEventLogin(Cause.source(source).build(), source);
if (!Sponge.getEventManager().post(event)) {
source.setLoggedIn(true);
sendResponse(ctx, requestId, TYPE_COMMAND, "");
Lantern.getLogger().info("Rcon connection from [" + ctx.channel().remoteAddress() + "]");
return;
}
}
source.setLoggedIn(false);
sendResponse(ctx, FAILURE, TYPE_COMMAND, "");
}
private static void handleCommand(ChannelHandlerContext ctx, String payload, int requestId) {
RconSource source = ctx.channel().attr(SOURCE).get();
if (!source.getLoggedIn()) {
sendResponse(ctx, FAILURE, TYPE_COMMAND, "");
return;
}
Sponge.getCommandManager().process(source, payload);
sendLargeResponse(ctx, requestId, source.flush());
}
private static void sendResponse(ChannelHandlerContext ctx, int requestId, int type, String payload) {
ByteBuf buf = ctx.alloc().buffer();
buf.writeIntLE(requestId);
buf.writeIntLE(type);
buf.writeBytes(payload.getBytes(StandardCharsets.UTF_8));
buf.writeByte(0);
buf.writeByte(0);
ctx.write(buf);
}
private static void sendLargeResponse(ChannelHandlerContext ctx, int requestId, String payload) {
if (payload.length() == 0) {
sendResponse(ctx, requestId, TYPE_RESPONSE, "");
return;
}
int start = 0;
while (start < payload.length()) {
int length = payload.length() - start;
int truncated = length > 2048 ? 2048 : length;
sendResponse(ctx, requestId, TYPE_RESPONSE, payload.substring(start, truncated));
start += truncated;
}
}
}