- Merge Breaking changes.

Signed-off-by: syeyoung <cyoung06@naver.com>

22 files changed, 731 insertions, 725 deletions

diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/Main.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/Main.java
index 7cc0f806..921adca9 100755
--- a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/Main.java
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/Main.java
@@ -61,7 +61,7 @@ public class Main
 
     private static Main main;
 
-    private File configDir;
+    private static File configDir;
 
     private DGInterface dgInterface;
     private Authenticator authenticator = new Authenticator();
@@ -69,6 +69,10 @@ public class Main
 
     private List<DungeonsGuideReloadListener> listeners = new ArrayList<>();
 
+    public static File getConfigDir() {
+        return configDir;
+    }
+
     public void addDGReloadListener(DungeonsGuideReloadListener dungeonsGuideReloadListener) {
         listeners.add(Objects.requireNonNull(dungeonsGuideReloadListener));
     }
@@ -111,7 +115,7 @@ public class Main
             listener.unloadReference();
         }
         if (currentLoader != null) {
-            currentLoader.unloadJar();
+            currentLoader.unloadDungeonsGuide();
         }
         currentLoader = null;
     }
@@ -126,8 +130,7 @@ public class Main
     }
     private void partialLoad(IDGLoader newLoader) throws ClassNotFoundException, InstantiationException, IllegalAccessException {
         if (dgInterface != null) throw new IllegalStateException("DG is loaded");
-        newLoader.loadJar(authenticator);
-        dgInterface = newLoader.getInstance();
+        dgInterface = newLoader.loadDungeonsGuide();
         currentLoader = newLoader;
     }
 
diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/AuthManager.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/AuthManager.java
new file mode 100644
index 00000000..23d9cf06
--- /dev/null
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/AuthManager.java
@@ -0,0 +1,140 @@
+package kr.syeyoung.dungeonsguide.launcher.auth;
+
+import com.google.common.base.Throwables;
+import com.google.common.util.concurrent.ThreadFactoryBuilder;
+import com.google.gson.JsonObject;
+import com.mojang.authlib.exceptions.AuthenticationException;
+import kr.syeyoung.dungeonsguide.launcher.auth.authprovider.AuthProvider;
+import kr.syeyoung.dungeonsguide.launcher.auth.authprovider.DgAuth.DgAuth;
+import kr.syeyoung.dungeonsguide.launcher.auth.authprovider.DgAuth.DgAuthUtil;
+import kr.syeyoung.dungeonsguide.mod.chat.ChatTransmitter;
+import kr.syeyoung.dungeonsguide.mod.events.impl.AuthChangedEvent;
+import kr.syeyoung.dungeonsguide.mod.stomp.StompManager;
+import lombok.Setter;
+import net.minecraft.client.Minecraft;
+import net.minecraftforge.common.MinecraftForge;
+import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
+import net.minecraftforge.fml.common.gameevent.TickEvent;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+import java.io.IOException;
+import java.security.KeyPair;
+import java.security.NoSuchAlgorithmException;
+import java.util.Objects;
+import java.util.concurrent.*;
+
+
+public class AuthManager {
+    Logger logger = LogManager.getLogger("AuthManger");
+
+    private static AuthManager INSTANCE;
+
+    public static AuthManager getInstance() {
+        if(INSTANCE == null) INSTANCE = new AuthManager();
+        return INSTANCE;
+    }
+
+    @Setter
+    private String baseserverurl = "https://dungeons.guide";
+
+    private AuthToken currentToken = new NullToken();
+
+    public String getToken() {
+        return currentToken.getToken();
+    }
+
+
+    public KeyPair getKeyPair(){
+        return currentToken.getRSAKeyForAuth();
+    }
+
+
+    private volatile boolean initlock = false;
+
+    public void init() {
+        if (initlock) {
+            logger.info("Cannot init AuthManger twice");
+            return;
+        }
+
+        reauth();
+
+        initlock = true;
+
+
+        MinecraftForge.EVENT_BUS.register(this);
+
+        ThreadFactory namedThreadFactory = new ThreadFactoryBuilder().setNameFormat("DgAuth Pool").build();
+        final ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1, namedThreadFactory);
+        scheduler.scheduleAtFixedRate(() -> {
+            if (getToken() != null) {
+                JsonObject obj = DgAuthUtil.getJwtPayload(getToken());
+                if (!obj.get("uuid").getAsString().replace("-", "").equals(Minecraft.getMinecraft().getSession().getPlayerID())) {
+                    shouldReAuth = true;
+                }
+            }
+
+
+        }, 10,2000, TimeUnit.MILLISECONDS);
+    }
+
+    boolean shouldReAuth = true;
+    int tickCounter;
+
+    @SubscribeEvent
+    public void onTickClientTick(TickEvent.ClientTickEvent event) {
+        if (event.phase != TickEvent.Phase.START) return;
+
+        if (tickCounter % 200 == 0) {
+            tickCounter = 0;
+            reauth();
+        }
+        tickCounter++;
+    }
+
+    public boolean isPlebUser(){
+        return Objects.equals(getInstance().getPlanType(), "OPENSOURCE");
+    }
+
+    public String getPlanType(){
+        if(getToken() == null) return null;
+
+
+       JsonObject jwt = DgAuthUtil.getJwtPayload(getToken());
+
+       if(!jwt.has("plan")) return null;
+
+       return jwt.get("plan").getAsString();
+
+    }
+
+    void reauth() {
+        if (!shouldReAuth) return;
+        shouldReAuth = false;
+        currentToken = new NullToken();
+        try {
+            currentProvider = new DgAuth(baseserverurl).createAuthProvider();
+            if (currentProvider.getToken() == null) {
+                shouldReAuth = true;
+                currentProvider = null;
+                ChatTransmitter.addToQueue("§eDungeons Guide §7:: §r§cDG auth failed, trying again in ten seconds", true);
+                logger.info("DG auth failed, trying again in a second");
+            } else {
+                // RE-AUTHed SUCCESSFULLY HOORAY
+                // for some reason the forge events don't work in pre init, so I call the callback directly
+                StompManager.getInstance().init();
+                MinecraftForge.EVENT_BUS.post(new AuthChangedEvent());
+            }
+        } catch (NoSuchAlgorithmException | AuthenticationException | IOException e) {
+
+            shouldReAuth = true;
+            currentProvider = null;
+            ChatTransmitter.addToQueue("§eDungeons Guide §7:: §r§cDG auth failed, trying again in ten seconds", true);
+            logger.error("Re-auth failed with message {}, trying again in a ten seconds", String.valueOf(Throwables.getRootCause(e)));
+        }
+
+    }
+
+
+}
diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/AuthToken.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/AuthToken.java
new file mode 100644
index 00000000..cb7c03da
--- /dev/null
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/AuthToken.java
@@ -0,0 +1,17 @@
+package kr.syeyoung.dungeonsguide.launcher.auth;
+
+import java.security.KeyPair;
+import java.security.interfaces.RSAKey;
+import java.time.Instant;
+
+public interface AuthToken {
+    boolean isUserVerified();
+    boolean hasFullCapability();
+    boolean isAuthenticated();
+
+    Instant getExpiryInstant();
+
+    KeyPair getRSAKeyForAuth();
+
+    String getToken();
+}
diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/AuthUtil.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/AuthUtil.java
new file mode 100644
index 00000000..9ce02643
--- /dev/null
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/AuthUtil.java
@@ -0,0 +1,70 @@
+package kr.syeyoung.dungeonsguide.launcher.auth;
+
+import com.google.gson.JsonElement;
+import com.google.gson.JsonParser;
+
+import javax.crypto.*;
+import javax.crypto.spec.IvParameterSpec;
+import javax.crypto.spec.SecretKeySpec;
+import javax.net.ssl.HttpsURLConnection;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.net.URL;
+import java.security.*;
+
+public class AuthUtil {
+    private AuthUtil() {}
+
+    public static KeyPair getKeyPair() throws NoSuchAlgorithmException {
+        KeyPairGenerator a = null;
+        a = KeyPairGenerator.getInstance("RSA");
+        a.initialize(1024);
+        return a.generateKeyPair();
+    }
+
+
+    public static JsonElement getJsonSecured(String u) throws IOException, NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException, InvalidAlgorithmParameterException{
+
+        int length = 0;
+        CipherInputStream cipherInputStream = null;
+
+        HttpsURLConnection httpsURLConnection = (HttpsURLConnection) new URL(u).openConnection();
+        httpsURLConnection.setRequestProperty("User-Agent", "DungeonsGuide/1.0");
+        httpsURLConnection.setRequestProperty("Content-Type", "application/json");
+        httpsURLConnection.setRequestMethod("GET");
+        httpsURLConnection.setRequestProperty("Authorization", AuthManager.getInstance().getToken());
+        httpsURLConnection.setDoInput(true);
+        httpsURLConnection.setDoOutput(true);
+
+        InputStream inputStream = httpsURLConnection.getInputStream();
+        byte[] lengthPayload = new byte[4];
+        inputStream.read(lengthPayload);
+        length = ((lengthPayload[0] & 0xFF) << 24) |
+                ((lengthPayload[1] & 0xFF) << 16) |
+                ((lengthPayload[2] & 0xFF) << 8) |
+                ((lengthPayload[3] & 0xFF));
+        while (inputStream.available() < length) ;
+        byte[] keyPayload = new byte[length];
+        inputStream.read(keyPayload);
+
+        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
+        cipher.init(Cipher.DECRYPT_MODE, AuthManager.getInstance().getKeyPair().getPrivate());
+        byte[] AESKey = cipher.doFinal(keyPayload);
+
+        cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
+        SecretKeySpec secretKeySpec = new SecretKeySpec(AESKey, "AES");
+        IvParameterSpec ivParameterSpec = new IvParameterSpec(AESKey);
+        cipher.init(Cipher.DECRYPT_MODE, secretKeySpec, ivParameterSpec);
+        cipherInputStream = new CipherInputStream(inputStream, cipher);
+        cipherInputStream.read(lengthPayload);
+        length = ((lengthPayload[0] & 0xFF) << 24) |
+                ((lengthPayload[1] & 0xFF) << 16) |
+                ((lengthPayload[2] & 0xFF) << 8) |
+                ((lengthPayload[3] & 0xFF));
+
+        httpsURLConnection.disconnect();
+
+        return new JsonParser().parse(new InputStreamReader(cipherInputStream));
+    }
+}
diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/InvalidDungeonsGuideCredentialsException.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/InvalidDungeonsGuideCredentialsException.java
new file mode 100644
index 00000000..ebe78196
--- /dev/null
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/InvalidDungeonsGuideCredentialsException.java
@@ -0,0 +1,8 @@
+package kr.syeyoung.dungeonsguide.launcher.auth;
+
+public class InvalidDungeonsGuideCredentialsException extends Throwable {
+
+    public InvalidDungeonsGuideCredentialsException(String message) {
+        super(message);
+    }
+}
diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/NullToken.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/NullToken.java
new file mode 100644
index 00000000..ddbfe58f
--- /dev/null
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/NullToken.java
@@ -0,0 +1,36 @@
+package kr.syeyoung.dungeonsguide.launcher.auth;
+
+import java.security.KeyPair;
+import java.time.Instant;
+
+public class NullToken implements AuthToken {
+    @Override
+    public boolean isUserVerified() {
+        return false;
+    }
+
+    @Override
+    public boolean hasFullCapability() {
+        return false;
+    }
+
+    @Override
+    public boolean isAuthenticated() {
+        return false;
+    }
+
+    @Override
+    public Instant getExpiryInstant() {
+        return Instant.MIN;
+    }
+
+    @Override
+    public KeyPair getRSAKeyForAuth() {
+        return null;
+    }
+
+    @Override
+    public String getToken() {
+        return null;
+    }
+}
diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/ResourceManager.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/ResourceManager.java
new file mode 100644
index 00000000..721b629f
--- /dev/null
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/ResourceManager.java
@@ -0,0 +1,164 @@
+package kr.syeyoung.dungeonsguide.launcher.auth;
+
+import lombok.Setter;
+import net.minecraftforge.common.MinecraftForge;
+import org.apache.commons.codec.binary.Base64;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+import javax.crypto.*;
+import javax.crypto.spec.IvParameterSpec;
+import javax.crypto.spec.SecretKeySpec;
+import javax.net.ssl.HttpsURLConnection;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.security.*;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.X509EncodedKeySpec;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipInputStream;
+
+public class ResourceManager {
+
+    Logger logger = LogManager.getLogger("ResourceManager");
+
+    @Setter
+    private String baseUrl;
+    @Setter
+    private String BASE64_X509ENCODEDKEYSPEC;
+    private final HashMap<String, byte[]> loadedResources = new HashMap<>();
+
+
+    private static ResourceManager instance;
+    public static ResourceManager getInstance() {
+        if(instance == null) {
+            instance = new ResourceManager();
+            MinecraftForge.EVENT_BUS.register(instance);
+        }
+        return instance;
+    }
+
+    private ResourceManager() {
+    }
+
+    public Map<String, byte[]> getResources() {
+        return loadedResources;
+    }
+
+
+    public void downloadAssets(String version) throws InvalidDungeonsGuideCredentialsException {
+        if(AuthManager.getInstance().getToken() == null) throw new InvalidDungeonsGuideCredentialsException("Not Authenticated while downloading assets");
+        try {
+            // version not being null indicates that the user is "premium"
+            // so we download the special version
+            if (version != null)
+                downloadSafe( baseUrl + "/resource/version?v=" + version, true);
+
+            if(!AuthManager.getInstance().isPlebUser()){
+                downloadSafe(baseUrl + "/resource/roomdata", false);
+            } else {
+                logger.error("The current User is a pleb not downloading user data");
+            }
+
+        } catch (Exception t) {
+            t.printStackTrace();
+        }
+
+    }
+
+    private void downloadSafe(String url, boolean isValidateSignature) throws IOException, NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException, InvalidAlgorithmParameterException, SignatureException, InvalidKeySpecException {
+        HttpsURLConnection dgConnection = (HttpsURLConnection) new URL(url).openConnection();
+        dgConnection.setRequestProperty("User-Agent", "DungeonsGuide/1.0");
+        dgConnection.setRequestProperty("Content-Type", "application/json");
+        dgConnection.setRequestMethod("GET");
+        dgConnection.setRequestProperty("Authorization", AuthManager.getInstance().getToken());
+        dgConnection.setDoInput(true);
+        dgConnection.setDoOutput(true);
+
+        InputStream inputStream = dgConnection.getInputStream();
+        byte[] lengthBytes = new byte[4];
+        inputStream.read(lengthBytes);
+        int length = ((lengthBytes[0] & 0xFF) << 24) |
+                ((lengthBytes[1] & 0xFF) << 16) |
+                ((lengthBytes[2] & 0xFF) << 8) |
+                ((lengthBytes[3] & 0xFF));
+        while (inputStream.available() < length) ;
+        byte[] keyPayload = new byte[length];
+        inputStream.read(keyPayload);
+
+        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
+        cipher.init(Cipher.DECRYPT_MODE, AuthManager.getInstance().getKeyPair().getPrivate());
+        byte[] h = cipher.doFinal(keyPayload);
+
+        cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
+        SecretKeySpec keySpec = new SecretKeySpec(h, "AES");
+        IvParameterSpec ivSpec = new IvParameterSpec(h);
+        cipher.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);
+        CipherInputStream cipherInputStream = new CipherInputStream(inputStream, cipher);
+
+        cipherInputStream.read(lengthBytes);
+        length = ((lengthBytes[0] & 0xFF) << 24) |
+                ((lengthBytes[1] & 0xFF) << 16) |
+                ((lengthBytes[2] & 0xFF) << 8) |
+                ((lengthBytes[3] & 0xFF));
+
+        int totalLen = length;
+        ByteArrayOutputStream bos = new ByteArrayOutputStream();
+        byte[] buff = new byte[256];
+        while (totalLen > 0) {
+            int len = cipherInputStream.read(buff, 0, Math.min(buff.length,  totalLen));
+            totalLen -= len;
+            bos.write(buff, 0, len);
+        }
+        byte[] body = bos.toByteArray();
+
+        byte[] signed;
+        if (isValidateSignature) {
+            cipherInputStream.read(lengthBytes,0 , 4);
+            length = ((lengthBytes[0] & 0xFF) << 24) |
+                    ((lengthBytes[1] & 0xFF) << 16) |
+                    ((lengthBytes[2] & 0xFF) << 8) |
+                    ((lengthBytes[3] & 0xFF));
+
+            totalLen = length;
+            bos = new ByteArrayOutputStream();
+            while (totalLen > 0) {
+                int len = cipherInputStream.read(buff, 0, Math.min(buff.length,  totalLen));
+                totalLen -= len;
+                bos.write(buff, 0, len);
+            }
+            signed = bos.toByteArray();
+
+            Signature sign = Signature.getInstance("SHA512withRSA");
+            sign.initVerify(getPublicKey(BASE64_X509ENCODEDKEYSPEC));
+            sign.update(body);
+            boolean truth = sign.verify(signed);
+            if (!truth) throw new SignatureException("DG SIGNATURE FORGED");
+        }
+
+        ZipInputStream zipInputStream = new ZipInputStream(new ByteArrayInputStream(body));
+        ZipEntry zipEntry;
+        while ((zipEntry=zipInputStream.getNextEntry()) != null) {
+            byte[] buffer = new byte[256];
+            ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
+            int p;
+            while((p = zipInputStream.read(buffer)) > 0) {
+                byteArrayOutputStream.write(buffer, 0, p);
+            }
+            this.loadedResources.put(zipEntry.getName(), byteArrayOutputStream.toByteArray());
+        }
+    }
+
+
+    public static PublicKey getPublicKey(String base64X509EncodedKeySpec) throws NoSuchAlgorithmException, InvalidKeySpecException {
+        X509EncodedKeySpec spec = new X509EncodedKeySpec(Base64.decodeBase64(base64X509EncodedKeySpec));
+
+        return KeyFactory.getInstance("RSA").generatePublic(spec);
+    }
+
+}
diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/AuthProvider.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/AuthProvider.java
new file mode 100644
index 00000000..d469c729
--- /dev/null
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/AuthProvider.java
@@ -0,0 +1,16 @@
+package kr.syeyoung.dungeonsguide.launcher.auth.authprovider;
+
+import com.mojang.authlib.exceptions.AuthenticationException;
+
+import java.io.IOException;
+import java.security.KeyPair;
+import java.security.NoSuchAlgorithmException;
+
+public interface AuthProvider {
+    String getToken();
+
+    KeyPair getRsaKey();
+
+
+    AuthProvider createAuthProvider() throws NoSuchAlgorithmException, AuthenticationException, IOException;
+}
diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/DgAuth/DgAuth.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/DgAuth/DgAuth.java
new file mode 100644
index 00000000..dca9ce33
--- /dev/null
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/DgAuth/DgAuth.java
@@ -0,0 +1,46 @@
+package kr.syeyoung.dungeonsguide.launcher.auth.authprovider.DgAuth;
+
+import com.mojang.authlib.exceptions.AuthenticationException;
+import kr.syeyoung.dungeonsguide.launcher.auth.AuthUtil;
+import kr.syeyoung.dungeonsguide.launcher.auth.authprovider.AuthProvider;
+
+import java.io.IOException;
+import java.security.KeyPair;
+import java.security.NoSuchAlgorithmException;
+
+public class DgAuth implements AuthProvider {
+
+    private final String authServerUrl;
+
+    public DgAuth(String authServerUrl){
+        this.authServerUrl = authServerUrl;
+    }
+
+    private String token;
+    private KeyPair rsaKey;
+
+    @Override
+    public String getToken() {
+        return token;
+    }
+
+    @Override
+    public KeyPair getRsaKey() {
+        return rsaKey;
+    }
+
+
+    @Override
+    public AuthProvider createAuthProvider() throws NoSuchAlgorithmException, AuthenticationException, IOException {
+        this.rsaKey = AuthUtil.getKeyPair();
+
+        String tempToken = DgAuthUtil.requestAuth(this.authServerUrl);
+
+        DgAuthUtil.checkSessionAuthenticity(tempToken);
+
+        this.token = DgAuthUtil.verifyAuth(tempToken, rsaKey.getPublic(), authServerUrl);
+
+        return this;
+    }
+
+}
diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/DgAuth/DgAuthUtil.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/DgAuth/DgAuthUtil.java
new file mode 100644
index 00000000..53b57e1a
--- /dev/null
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/DgAuth/DgAuthUtil.java
@@ -0,0 +1,88 @@
+package kr.syeyoung.dungeonsguide.launcher.auth.authprovider.DgAuth;
+
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+import com.mojang.authlib.GameProfile;
+import com.mojang.authlib.exceptions.AuthenticationException;
+import com.mojang.authlib.minecraft.MinecraftSessionService;
+import net.minecraft.client.Minecraft;
+import net.minecraft.util.Session;
+import org.apache.commons.codec.binary.Base64;
+import org.apache.commons.io.IOUtils;
+
+import javax.net.ssl.HttpsURLConnection;
+import java.io.IOException;
+import java.math.BigInteger;
+import java.net.URL;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.security.PublicKey;
+
+public class DgAuthUtil {
+    private DgAuthUtil(){}
+
+    public static String requestAuth(String baseurl) throws IOException {
+        GameProfile profile = Minecraft.getMinecraft().getSession().getProfile();
+
+        HttpsURLConnection connection = (HttpsURLConnection) new URL(baseurl + "/auth/requestAuth").openConnection();
+        connection.setRequestProperty("User-Agent", "DungeonsGuide/1.0");
+        connection.setRequestProperty("Content-Type", "application/json");
+        connection.setRequestMethod("POST");
+        connection.setDoInput(true);
+        connection.setDoOutput(true);
+
+        connection.getOutputStream().write(("{\"uuid\":\""+profile.getId().toString()+"\",\"nickname\":\""+profile.getName()+"\"}").getBytes());
+        String payload = String.join("\n", IOUtils.readLines(connection.getErrorStream() == null ? connection.getInputStream() : connection.getErrorStream()));
+
+        JsonObject json = (JsonObject) new JsonParser().parse(payload);
+
+        if (!"ok".equals(json.get("status").getAsString())) {
+            return null;
+        }
+        return json.get("data").getAsString();
+    }
+
+    public static void checkSessionAuthenticity(String tempToken) throws NoSuchAlgorithmException, AuthenticationException {
+        JsonObject d = getJwtPayload(tempToken);
+        byte[] sharedSecret = Base64.decodeBase64(d.get("sharedSecret").getAsString());
+        byte[] publicKey =Base64.decodeBase64(d.get("publicKey").getAsString());
+        String hash = calculateServerHash(sharedSecret, publicKey);
+
+        Session session = Minecraft.getMinecraft().getSession();
+        MinecraftSessionService yggdrasilMinecraftSessionService = Minecraft.getMinecraft().getSessionService();
+        yggdrasilMinecraftSessionService.joinServer(session.getProfile(), session.getToken(), hash);
+    }
+
+    public static String verifyAuth(String tempToken, PublicKey clientKey, String baseurl) throws IOException {
+        HttpsURLConnection urlConnection = (HttpsURLConnection) new URL(baseurl + "/auth/authenticate").openConnection();
+        urlConnection.setRequestMethod("POST");
+        urlConnection.setRequestProperty("User-Agent", "DungeonsGuide/1.0");
+        urlConnection.setRequestProperty("Content-Type", "application/json");
+        urlConnection.setDoInput(true);
+        urlConnection.setDoOutput(true);
+
+        urlConnection.getOutputStream().write(("{\"jwt\":\""+tempToken+"\",\"publicKey\":\""+Base64.encodeBase64URLSafeString(clientKey.getEncoded())+"\"}").getBytes());
+        String payload = String.join("\n", IOUtils.readLines(urlConnection.getErrorStream() == null ? urlConnection.getInputStream() : urlConnection.getErrorStream()));
+
+        JsonObject jsonObject = (JsonObject) new JsonParser().parse(payload);
+        if (!"ok".equals(jsonObject.get("status").getAsString())) {
+            return null;
+        }
+        return jsonObject.get("data").getAsString();
+    }
+
+    public static JsonObject getJwtPayload(String jwt) {
+        String midPart = jwt.split("\\.")[1].replace("+", "-").replace("/", "_");
+        String base64Decode = new String(Base64.decodeBase64(midPart)); // padding
+        return (JsonObject) new JsonParser().parse(base64Decode);
+    }
+
+    public static String calculateServerHash(byte[] a, byte[] b) throws NoSuchAlgorithmException {
+        MessageDigest c = MessageDigest.getInstance("SHA-1");
+        c.update("".getBytes());
+        c.update(a);
+        c.update(b);
+        byte[] d = c.digest();
+        return new BigInteger(d).toString(16);
+    }
+}
diff --git a/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/NullAuth.java b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/NullAuth.java
new file mode 100644
index 00000000..303cfb0a
--- /dev/null
+++ b/loader/src/main/java/kr/syeyoung/dungeonsguide/launcher/auth/authprovider/NullAuth.java
@@ -0,0 +1,62 @@
+package kr.syeyoung.dungeonsguide.launcher.auth.authprovider;
+
+import com.mojang.authlib.exceptions.AuthenticationException;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+import java.io.IOException;
+import java.security.KeyPair;
+import java.security.NoSuchAlgorithmException;
+import java.security.PrivateKey;
+import java.security.PublicKey;
+
+public class NullAuth implements AuthProvider {