ix9wbCJV

1// ...
2// All NMS imports related to net.minecraft.server.v1_10_R1
3// ...
4public class SessChkMain extends JavaPlugin {
5    // ...
6    @Override
7    public void onEnable() {
8        // ...
9        this.registerListener();
10    }
11    // ...
12    private class SessChkRun implements Runnable {
13        private SessChkMain plugin;
14        private String name;
15        private String serverId;
16        public SessChkRun(SessChkMain plugin, String name, String serverId) {
17            this.plugin = plugin;
18            this.name = name;
19            this.serverId = serverId;
20        }
21        @Override
22        public void run() {
23            this.plugin.checkSession(this.name, this.serverId);
24        }
25    }
26    private class EncBegAdapter extends PacketAdapter {
27        private SessChkMain plugin;
28        public EncBegAdapter(SessChkMain plugin) {
29            super(plugin, PacketType.Login.Client.ENCRYPTION_BEGIN);
30            this.plugin = plugin;
31        }
32        @Override
33        public void onPacketSending(PacketEvent event) {
34            this.plugin.getLogger().info("Received LoginInEncryptionBegin from " + event.getPlayer().getName() + " [" + event.getPlayer().getUniqueId().toString() + "]");
35            String serverId = this.plugin.getServerId((PacketLoginInEncryptionBegin) event.getPacket().getHandle(), ((CraftServer) this.plugin.getServer()).getServer());
36            this.plugin.getLogger().info("Decrypted his sent server ID (\"" + serverId + "\") and requesting mojang check.");
37            this.plugin.getServer().getScheduler().runTaskAsynchronously(this.plugin, new SessChkRun(this.plugin, event.getPlayer().getName(), serverId));
38        }
39    }
40    private void registerListener() {
41        ProtocolLibrary.getProtocolManager().addPacketListener(new EncBegAdapter(this));
42    }
43    public String getServerId(PacketLoginInEncryptionBegin packet, MinecraftServer server) {
44        // Decryption copied from "net.minecraft.server.v1_10_R1.LoginListener.a(PacketLoginInEncryptionBegin)"
45        SecretKey loginKey = ((PacketLoginInEncryptionBegin) packet).a(server.O().getPrivate());
46        return new BigInteger(MinecraftEncryption.a("", server.O().getPublic(), loginKey)).toString(16);
47    }
48    public void checkSession(String name, String serverId) {
49        try {
50            URL url= new URL("https://sessionserver.mojang.com/session/minecraft/hasJoined?username=" + name + "&serverId=" + serverId);
51            this.getLogger().info("Starting HTTP GET request to \"https://sessionserver.mojang.com/session/minecraft/hasJoined?username=" + name + "&serverId=" + serverId + "\"");
52            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
53            if (connection.getResponseCode() == HttpURLConnection.HTTP_OK) {
54                InputStream streamIn = connection.getInputStream();
55                byte[] buffer = new byte[streamIn.available()];
56                streamIn.read(buffer);
57                streamIn.close();
58                this.getLogger().info("Received data: " + new String(buffer, "UTF-8"));
59            } else {
60                this.getLogger().info("Error: HTTP/" + Integer.toString(connection.getResponseCode()) + ", " + connection.getResponseMessage());
61            }
62        } catch (IOException e) {
63            e.printStackTrace();
64        }
65    }
66}