PicoLimbo/src/main/java/ua/nanit/limbo/connection/ClientConnection.java
2023-09-27 20:06:54 +03:00

336 lines
11 KiB
Java

/*
* Copyright (C) 2020 Nan1t
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
package ua.nanit.limbo.connection;
import com.grack.nanojson.JsonArray;
import com.grack.nanojson.JsonObject;
import com.grack.nanojson.JsonParser;
import com.grack.nanojson.JsonParserException;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import org.jetbrains.annotations.NotNull;
import ua.nanit.limbo.connection.pipeline.PacketDecoder;
import ua.nanit.limbo.connection.pipeline.PacketEncoder;
import ua.nanit.limbo.protocol.ByteMessage;
import ua.nanit.limbo.protocol.Packet;
import ua.nanit.limbo.protocol.packets.login.PacketDisconnect;
import ua.nanit.limbo.protocol.packets.play.PacketKeepAlive;
import ua.nanit.limbo.protocol.registry.State;
import ua.nanit.limbo.protocol.registry.Version;
import ua.nanit.limbo.server.LimboServer;
import ua.nanit.limbo.server.Logger;
import ua.nanit.limbo.util.UuidUtil;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.security.InvalidKeyException;
import java.security.MessageDigest;
import java.util.UUID;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;
public class ClientConnection extends ChannelInboundHandlerAdapter {
private final LimboServer server;
private final Channel channel;
private final GameProfile gameProfile;
private final PacketDecoder decoder;
private final PacketEncoder encoder;
private State state;
private Version clientVersion;
private SocketAddress address;
private int velocityLoginMessageId = -1;
public ClientConnection(Channel channel, LimboServer server, PacketDecoder decoder, PacketEncoder encoder) {
this.server = server;
this.channel = channel;
this.decoder = decoder;
this.encoder = encoder;
this.address = channel.remoteAddress();
this.gameProfile = new GameProfile();
}
public UUID getUuid() {
return gameProfile.getUuid();
}
public String getUsername() {
return gameProfile.getUsername();
}
public SocketAddress getAddress() {
return address;
}
public Version getClientVersion() {
return clientVersion;
}
public GameProfile getGameProfile() {
return gameProfile;
}
@Override
public void channelInactive(@NotNull ChannelHandlerContext ctx) throws Exception {
if (state.equals(State.PLAY) || state.equals(State.CONFIGURATION)) {
server.getConnections().removeConnection(this);
}
super.channelInactive(ctx);
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
if (channel.isActive()) {
Logger.error("Unhandled exception: ", cause);
}
}
@Override
public void channelRead(@NotNull ChannelHandlerContext ctx, @NotNull Object msg) {
handlePacket(msg);
}
public void handlePacket(Object packet) {
if (packet instanceof Packet) {
((Packet)packet).handle(this, server);
}
}
public void fireLoginSuccess() {
if (server.getConfig().getInfoForwarding().isModern() && velocityLoginMessageId == -1) {
disconnectLogin("You need to connect with Velocity");
return;
}
sendPacket(PacketSnapshots.PACKET_LOGIN_SUCCESS);
server.getConnections().addConnection(this);
// Preparing for configuration mode
if (clientVersion.moreOrEqual(Version.V1_20_2)) {
updateEncoderState(State.CONFIGURATION);
return;
}
spawnPlayer();
}
public void spawnPlayer() {
updateState(State.PLAY);
Runnable sendPlayPackets = () -> {
writePacket(PacketSnapshots.PACKET_JOIN_GAME);
writePacket(PacketSnapshots.PACKET_PLAYER_ABILITIES);
if (clientVersion.less(Version.V1_9)) {
writePacket(PacketSnapshots.PACKET_PLAYER_POS_AND_LOOK_LEGACY);
} else {
writePacket(PacketSnapshots.PACKET_PLAYER_POS_AND_LOOK);
}
if (clientVersion.moreOrEqual(Version.V1_19_3))
writePacket(PacketSnapshots.PACKET_SPAWN_POSITION);
if (server.getConfig().isUsePlayerList() || clientVersion.equals(Version.V1_16_4))
writePacket(PacketSnapshots.PACKET_PLAYER_INFO);
if (clientVersion.moreOrEqual(Version.V1_13)) {
writePacket(PacketSnapshots.PACKET_DECLARE_COMMANDS);
if (PacketSnapshots.PACKET_PLUGIN_MESSAGE != null)
writePacket(PacketSnapshots.PACKET_PLUGIN_MESSAGE);
}
if (PacketSnapshots.PACKET_BOSS_BAR != null && clientVersion.moreOrEqual(Version.V1_9))
writePacket(PacketSnapshots.PACKET_BOSS_BAR);
if (PacketSnapshots.PACKET_JOIN_MESSAGE != null)
writePacket(PacketSnapshots.PACKET_JOIN_MESSAGE);
if (PacketSnapshots.PACKET_TITLE_TITLE != null && clientVersion.moreOrEqual(Version.V1_8))
writeTitle();
if (PacketSnapshots.PACKET_HEADER_AND_FOOTER != null && clientVersion.moreOrEqual(Version.V1_8))
writePacket(PacketSnapshots.PACKET_HEADER_AND_FOOTER);
sendKeepAlive();
};
if (clientVersion.lessOrEqual(Version.V1_7_6)) {
this.channel.eventLoop().schedule(sendPlayPackets, 100, TimeUnit.MILLISECONDS);
} else {
sendPlayPackets.run();
}
}
public void onLoginAcknowledgedReceived() {
updateState(State.CONFIGURATION);
if (PacketSnapshots.PACKET_PLUGIN_MESSAGE != null)
writePacket(PacketSnapshots.PACKET_PLUGIN_MESSAGE);
writePacket(PacketSnapshots.PACKET_REGISTRY_DATA);
sendPacket(PacketSnapshots.PACKET_FINISH_CONFIGURATION);
}
public void disconnectLogin(String reason) {
if (isConnected() && state == State.LOGIN) {
PacketDisconnect disconnect = new PacketDisconnect();
disconnect.setReason(reason);
sendPacketAndClose(disconnect);
}
}
public void writeTitle() {
if (clientVersion.moreOrEqual(Version.V1_17)) {
writePacket(PacketSnapshots.PACKET_TITLE_TITLE);
writePacket(PacketSnapshots.PACKET_TITLE_SUBTITLE);
writePacket(PacketSnapshots.PACKET_TITLE_TIMES);
} else {
writePacket(PacketSnapshots.PACKET_TITLE_LEGACY_TITLE);
writePacket(PacketSnapshots.PACKET_TITLE_LEGACY_SUBTITLE);
writePacket(PacketSnapshots.PACKET_TITLE_LEGACY_TIMES);
}
}
public void sendKeepAlive() {
if (state.equals(State.PLAY)) {
PacketKeepAlive keepAlive = new PacketKeepAlive();
keepAlive.setId(ThreadLocalRandom.current().nextLong());
sendPacket(keepAlive);
}
}
public void sendPacket(Object packet) {
if (isConnected())
channel.writeAndFlush(packet, channel.voidPromise());
}
public void sendPacketAndClose(Object packet) {
if (isConnected())
channel.writeAndFlush(packet).addListener(ChannelFutureListener.CLOSE);
}
public void writePacket(Object packet) {
if (isConnected())
channel.write(packet, channel.voidPromise());
}
public boolean isConnected() {
return channel.isActive();
}
public void updateState(State state) {
this.state = state;
decoder.updateState(state);
encoder.updateState(state);
}
public void updateDecoderState(State state) {
decoder.updateState(state);
}
public void updateEncoderState(State state) {
encoder.updateState(state);
}
public void updateVersion(Version version) {
clientVersion = version;
decoder.updateVersion(version);
encoder.updateVersion(version);
}
public void setAddress(String host) {
this.address = new InetSocketAddress(host, ((InetSocketAddress)this.address).getPort());
}
boolean checkBungeeGuardHandshake(String handshake) {
String[] split = handshake.split("\00");
if (split.length != 4)
return false;
String socketAddressHostname = split[1];
UUID uuid = UuidUtil.fromString(split[2]);
JsonArray arr;
try {
arr = JsonParser.array().from(split[3]);
} catch (JsonParserException e) {
return false;
}
String token = null;
for (Object obj : arr) {
if (obj instanceof JsonObject) {
JsonObject prop = (JsonObject) obj;
if (prop.getString("name").equals("bungeeguard-token")) {
token = prop.getString("value");
break;
}
}
}
if (!server.getConfig().getInfoForwarding().hasToken(token))
return false;
setAddress(socketAddressHostname);
gameProfile.setUuid(uuid);
Logger.debug("Successfully verified BungeeGuard token");
return true;
}
int getVelocityLoginMessageId() {
return velocityLoginMessageId;
}
void setVelocityLoginMessageId(int velocityLoginMessageId) {
this.velocityLoginMessageId = velocityLoginMessageId;
}
boolean checkVelocityKeyIntegrity(ByteMessage buf) {
byte[] signature = new byte[32];
buf.readBytes(signature);
byte[] data = new byte[buf.readableBytes()];
buf.getBytes(buf.readerIndex(), data);
try {
Mac mac = Mac.getInstance("HmacSHA256");
mac.init(new SecretKeySpec(server.getConfig().getInfoForwarding().getSecretKey(), "HmacSHA256"));
byte[] mySignature = mac.doFinal(data);
if (!MessageDigest.isEqual(signature, mySignature))
return false;
} catch (InvalidKeyException |java.security.NoSuchAlgorithmException e) {
throw new AssertionError(e);
}
int version = buf.readVarInt();
if (version != 1)
throw new IllegalStateException("Unsupported forwarding version " + version + ", wanted " + '\001');
return true;
}
}