Implemented joining with local minecraft accounts

src/main/java/net/raphimc/viaproxy/ViaProxy.java

@@ -21,6 +21,7 @@ import net.raphimc.viaproxy.protocolhack.ProtocolHack;
 import net.raphimc.viaproxy.proxy.ProxyConnection;
 import net.raphimc.viaproxy.proxy.client2proxy.Client2ProxyChannelInitializer;
 import net.raphimc.viaproxy.proxy.client2proxy.Client2ProxyHandler;
+import net.raphimc.viaproxy.saves.SaveManager;
 import net.raphimc.viaproxy.ui.ViaProxyUI;
 import net.raphimc.viaproxy.util.logging.Logger;
 
@@ -31,8 +32,10 @@ public class ViaProxy {
 
     public static final String VERSION = "${version}";
 
+    public static SaveManager saveManager;
     public static NetServer currentProxyServer;
     public static Thread loaderThread;
+    public static Thread accountRefreshThread;
     public static ChannelGroup c2pChannels;
 
     public static void main(String[] args) throws Throwable {
@@ -49,6 +52,7 @@ public class ViaProxy {
         Logger.setup();
         ConsoleHandler.hookConsole();
         Logger.LOGGER.info("Initializing ViaProxy v" + VERSION + "...");
+        saveManager = new SaveManager();
         VersionEnum.init();
         setNettyParameters();
         MCPipeline.useOptimizedPipeline();
@@ -57,12 +61,17 @@ public class ViaProxy {
             ProtocolHack.init();
             PluginManager.loadPlugins();
         }, "ViaProtocolHack-Loader");
+        accountRefreshThread = new Thread(() -> {
+            saveManager.accountsSave.refreshAccounts();
+        }, "AccountRefresh");
 
         if (args.length == 0 && !GraphicsEnvironment.isHeadless()) {
             loaderThread.start();
+            accountRefreshThread.start();
             final ViaProxyUI[] ui = new ViaProxyUI[1];
             SwingUtilities.invokeLater(() -> ui[0] = new ViaProxyUI());
             loaderThread.join();
+            accountRefreshThread.join();
             ui[0].setReady();
             Logger.LOGGER.info("ViaProxy started successfully!");
             return;

src/main/java/net/raphimc/viaproxy/cli/options/Options.java

@@ -1,6 +1,7 @@
 package net.raphimc.viaproxy.cli.options;
 
 import joptsimple.*;
+import net.raphimc.mcauth.step.java.StepMCProfile;
 import net.raphimc.vialegacy.util.VersionEnum;
 import net.raphimc.viaproxy.util.logging.Logger;
 
@@ -27,6 +28,9 @@ public class Options {
     public static boolean LOCAL_SOCKET_AUTH;
     public static boolean BETACRAFT_AUTH;
 
+    // GUI only config options
+    public static StepMCProfile.MCProfile MC_ACCOUNT;
+
     public static void parse(final String[] args) throws IOException {
         final OptionParser parser = new OptionParser();
         final OptionSpec<Void> help = parser.acceptsAll(asList("help", "h", "?"), "Get a list of all arguments").forHelp();

src/main/java/net/raphimc/viaproxy/protocolhack/providers/ViaProxyOldAuthProvider.java

@@ -2,14 +2,14 @@ package net.raphimc.viaproxy.protocolhack.providers;
 
 import com.viaversion.viaversion.api.connection.UserConnection;
 import net.raphimc.vialegacy.protocols.release.protocol1_3_1_2to1_2_4_5.providers.OldAuthProvider;
-import net.raphimc.viaproxy.proxy.CustomPayloadInterface;
+import net.raphimc.viaproxy.proxy.ExternalInterface;
 import net.raphimc.viaproxy.proxy.ProxyConnection;
 
 public class ViaProxyOldAuthProvider extends OldAuthProvider {
 
     @Override
     public void sendAuthRequest(final UserConnection user, final String serverId) throws Throwable {
-        CustomPayloadInterface.joinServer(serverId, ProxyConnection.fromUserConnection(user));
+        ExternalInterface.joinServer(serverId, ProxyConnection.fromUserConnection(user));
     }
 
 }

src/main/java/net/raphimc/viaproxy/proxy/CustomPayloadInterface.java

@@ -1,66 +0,0 @@
-package net.raphimc.viaproxy.proxy;
-
-import io.netty.buffer.ByteBuf;
-import io.netty.buffer.Unpooled;
-import net.raphimc.netminecraft.packet.PacketTypes;
-import net.raphimc.netminecraft.packet.impl.login.C2SLoginKeyPacket1_19;
-import net.raphimc.viaproxy.cli.options.Options;
-import net.raphimc.viaproxy.util.LocalSocketClient;
-import net.raphimc.viaproxy.util.logging.Logger;
-
-import java.math.BigInteger;
-import java.nio.charset.StandardCharsets;
-import java.util.Base64;
-import java.util.concurrent.*;
-
-public class CustomPayloadInterface {
-
-    public static final String OPENAUTHMOD_BASE_CHANNEL = "oam:";
-    public static final byte[] OPENAUTHMOD_LEGACY_MAGIC_BYTES = new byte[]{2, 20, 12, 3}; // 1.8 - 1.12.2
-    public static final String OPENAUTHMOD_LEGACY_MAGIC_STRING = new String(OPENAUTHMOD_LEGACY_MAGIC_BYTES, StandardCharsets.UTF_8); // 1.8 - 1.12.2
-    public static final int OPENAUTHMOD_LEGACY_MAGIC_INT = new BigInteger(OPENAUTHMOD_LEGACY_MAGIC_BYTES).intValueExact(); // 1.8 - 1.12.2
-
-    // Request
-    public static final String OPENAUTHMOD_JOIN_CHANNEL = OPENAUTHMOD_BASE_CHANNEL + "join"; // 1.8 - latest
-    public static final String OPENAUTHMOD_SIGN_NONCE_CHANNEL = OPENAUTHMOD_BASE_CHANNEL + "sign_nonce"; // 1.19 - latest
-
-    // Response
-    public static final String OPENAUTHMOD_DATA_CHANNEL = OPENAUTHMOD_BASE_CHANNEL + "data"; // 1.8 - latest
-
-    public static void joinServer(final String serverIdHash, final ProxyConnection proxyConnection) throws InterruptedException, ExecutionException {
-        Logger.u_info("auth", proxyConnection.getC2P().remoteAddress(), proxyConnection.getGameProfile(), "Trying to join online mode server");
-        if (Options.OPENAUTHMOD_AUTH) {
-            try {
-                final ByteBuf response = proxyConnection.sendCustomPayload(OPENAUTHMOD_JOIN_CHANNEL, PacketTypes.writeString(Unpooled.buffer(), serverIdHash)).get(6, TimeUnit.SECONDS);
-                if (response == null) throw new TimeoutException();
-                if (response.isReadable() && !response.readBoolean()) throw new TimeoutException();
-            } catch (TimeoutException e) {
-                proxyConnection.kickClient("§cAuthentication cancelled! You need to install OpenAuthMod in order to join this server.");
-            }
-        } else if (Options.LOCAL_SOCKET_AUTH) {
-            new LocalSocketClient(48941).request("authenticate", serverIdHash);
-        }
-    }
-
-    public static void signNonce(final byte[] nonce, final C2SLoginKeyPacket1_19 packet, final ProxyConnection proxyConnection) throws InterruptedException, ExecutionException {
-        Logger.u_info("auth", proxyConnection.getC2P().remoteAddress(), proxyConnection.getGameProfile(), "Requesting nonce signature");
-        if (Options.OPENAUTHMOD_AUTH) {
-            try {
-                final ByteBuf response = proxyConnection.sendCustomPayload(OPENAUTHMOD_SIGN_NONCE_CHANNEL, PacketTypes.writeByteArray(Unpooled.buffer(), nonce)).get(4, TimeUnit.SECONDS);
-                if (response == null) throw new TimeoutException();
-                if (!response.readBoolean()) throw new TimeoutException();
-                packet.salt = response.readLong();
-                packet.signature = PacketTypes.readByteArray(response);
-            } catch (TimeoutException e) {
-                proxyConnection.kickClient("§cAuthentication cancelled! You need to install OpenAuthMod in order to join this server.");
-            }
-        } else if (Options.LOCAL_SOCKET_AUTH) {
-            final String[] response = new LocalSocketClient(48941).request("sign_nonce", Base64.getEncoder().encodeToString(nonce));
-            if (response != null && response[0].equals("success")) {
-                packet.salt = Long.valueOf(response[1]);
-                packet.signature = Base64.getDecoder().decode(response[2]);
-            }
-        }
-    }
-
-}

src/main/java/net/raphimc/viaproxy/proxy/ExternalInterface.java

@@ -0,0 +1,123 @@
+package net.raphimc.viaproxy.proxy;
+
+import com.github.steveice10.mc.auth.data.GameProfile;
+import com.github.steveice10.mc.auth.util.UUIDSerializer;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+import net.raphimc.netminecraft.packet.PacketTypes;
+import net.raphimc.netminecraft.packet.impl.login.*;
+import net.raphimc.viaproxy.cli.options.Options;
+import net.raphimc.viaproxy.protocolhack.providers.ViaProxyGameProfileFetcher;
+import net.raphimc.viaproxy.util.LocalSocketClient;
+import net.raphimc.viaproxy.util.logging.Logger;
+
+import java.math.BigInteger;
+import java.nio.charset.StandardCharsets;
+import java.security.*;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.X509EncodedKeySpec;
+import java.time.Instant;
+import java.util.Base64;
+import java.util.UUID;
+import java.util.concurrent.*;
+
+public class ExternalInterface {
+
+    public static final String OPENAUTHMOD_BASE_CHANNEL = "oam:";
+    public static final byte[] OPENAUTHMOD_LEGACY_MAGIC_BYTES = new byte[]{2, 20, 12, 3}; // 1.8 - 1.12.2
+    public static final String OPENAUTHMOD_LEGACY_MAGIC_STRING = new String(OPENAUTHMOD_LEGACY_MAGIC_BYTES, StandardCharsets.UTF_8); // 1.8 - 1.12.2
+    public static final int OPENAUTHMOD_LEGACY_MAGIC_INT = new BigInteger(OPENAUTHMOD_LEGACY_MAGIC_BYTES).intValueExact(); // 1.8 - 1.12.2
+
+    // Request
+    public static final String OPENAUTHMOD_JOIN_CHANNEL = OPENAUTHMOD_BASE_CHANNEL + "join"; // 1.8 - latest
+    public static final String OPENAUTHMOD_SIGN_NONCE_CHANNEL = OPENAUTHMOD_BASE_CHANNEL + "sign_nonce"; // 1.19 - latest
+
+    // Response
+    public static final String OPENAUTHMOD_DATA_CHANNEL = OPENAUTHMOD_BASE_CHANNEL + "data"; // 1.8 - latest
+
+
+    public static void fillPlayerData(final C2SLoginHelloPacket1_7 loginHello, final ProxyConnection proxyConnection) throws NoSuchAlgorithmException, InvalidKeySpecException {
+        proxyConnection.setLoginHelloPacket(loginHello);
+        if (proxyConnection.getLoginHelloPacket() instanceof C2SLoginHelloPacket1_19_3) {
+            proxyConnection.setGameProfile(new GameProfile(((C2SLoginHelloPacket1_19_3) proxyConnection.getLoginHelloPacket()).uuid, proxyConnection.getLoginHelloPacket().name));
+        } else {
+            proxyConnection.setGameProfile(new GameProfile((UUID) null, loginHello.name));
+        }
+
+        if (Options.LOCAL_SOCKET_AUTH) {
+            String[] response = new LocalSocketClient(48941).request("getusername");
+            if (response != null && response[0].equals("success")) {
+                proxyConnection.setGameProfile(new GameProfile((UUID) null, response[1]));
+            }
+
+            response = new LocalSocketClient(48941).request("get_public_key_data");
+            if (response != null && response[0].equals("success")) {
+                final String name = proxyConnection.getGameProfile().getName();
+                final UUID uuid = UUIDSerializer.fromString(response[1].replaceFirst("(\\p{XDigit}{8})(\\p{XDigit}{4})(\\p{XDigit}{4})(\\p{XDigit}{4})(\\p{XDigit}+)", "$1-$2-$3-$4-$5"));
+                final PublicKey publicKey = KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(Base64.getDecoder().decode(response[2])));
+                final byte[] keySignature = Base64.getDecoder().decode(response[3]);
+                final Instant expiresAt = Instant.ofEpochMilli(Long.parseLong(response[4]));
+
+                proxyConnection.setGameProfile(new GameProfile(uuid, name));
+                proxyConnection.setLoginHelloPacket(new C2SLoginHelloPacket1_19_3(name, expiresAt, publicKey, keySignature, uuid));
+            }
+        } else if (Options.MC_ACCOUNT != null) {
+            proxyConnection.setGameProfile(new GameProfile(Options.MC_ACCOUNT.id(), Options.MC_ACCOUNT.name()));
+            // TODO: Key
+        }
+
+        proxyConnection.getLoginHelloPacket().name = proxyConnection.getGameProfile().getName();
+        if (proxyConnection.getLoginHelloPacket() instanceof C2SLoginHelloPacket1_19_3) {
+            ((C2SLoginHelloPacket1_19_3) proxyConnection.getLoginHelloPacket()).uuid = proxyConnection.getGameProfile().getId();
+        }
+    }
+
+    public static void joinServer(final String serverIdHash, final ProxyConnection proxyConnection) throws InterruptedException, ExecutionException {
+        Logger.u_info("auth", proxyConnection.getC2P().remoteAddress(), proxyConnection.getGameProfile(), "Trying to join online mode server");
+        if (Options.OPENAUTHMOD_AUTH) {
+            try {
+                final ByteBuf response = proxyConnection.sendCustomPayload(OPENAUTHMOD_JOIN_CHANNEL, PacketTypes.writeString(Unpooled.buffer(), serverIdHash)).get(6, TimeUnit.SECONDS);
+                if (response == null) throw new TimeoutException();
+                if (response.isReadable() && !response.readBoolean()) throw new TimeoutException();
+            } catch (TimeoutException e) {
+                proxyConnection.kickClient("§cAuthentication cancelled! You need to install OpenAuthMod in order to join this server.");
+            }
+        } else if (Options.LOCAL_SOCKET_AUTH) {
+            new LocalSocketClient(48941).request("authenticate", serverIdHash);
+        } else if (Options.MC_ACCOUNT != null) {
+            try {
+                ViaProxyGameProfileFetcher.sessionService.joinServer(new GameProfile(Options.MC_ACCOUNT.id(), Options.MC_ACCOUNT.name()), Options.MC_ACCOUNT.prevResult().prevResult().access_token(), serverIdHash);
+            } catch (Throwable e) {
+                proxyConnection.kickClient("§cFailed to authenticate with Mojang servers! Please try again later.");
+            }
+        } else {
+            proxyConnection.kickClient("§cThis server is in online mode and requires a valid authentication mode.");
+        }
+    }
+
+    public static void signNonce(final byte[] nonce, final C2SLoginKeyPacket1_19 packet, final ProxyConnection proxyConnection) throws InterruptedException, ExecutionException {
+        Logger.u_info("auth", proxyConnection.getC2P().remoteAddress(), proxyConnection.getGameProfile(), "Requesting nonce signature");
+        if (Options.OPENAUTHMOD_AUTH) {
+            try {
+                final ByteBuf response = proxyConnection.sendCustomPayload(OPENAUTHMOD_SIGN_NONCE_CHANNEL, PacketTypes.writeByteArray(Unpooled.buffer(), nonce)).get(4, TimeUnit.SECONDS);
+                if (response == null) throw new TimeoutException();
+                if (!response.readBoolean()) throw new TimeoutException();
+                packet.salt = response.readLong();
+                packet.signature = PacketTypes.readByteArray(response);
+            } catch (TimeoutException e) {
+                proxyConnection.kickClient("§cAuthentication cancelled! You need to install OpenAuthMod in order to join this server.");
+            }
+        } else if (Options.LOCAL_SOCKET_AUTH) {
+            final String[] response = new LocalSocketClient(48941).request("sign_nonce", Base64.getEncoder().encodeToString(nonce));
+            if (response != null && response[0].equals("success")) {
+                packet.salt = Long.valueOf(response[1]);
+                packet.signature = Base64.getDecoder().decode(response[2]);
+            }
+        } else if (Options.MC_ACCOUNT != null) { // TODO: Key
+            proxyConnection.kickClient("§cJoining servers which requires a signed nonce is not yet supported.");
+        } else {
+            proxyConnection.kickClient("§cThis server is in online mode and requires a valid authentication mode.");
+        }
+    }
+
+}

src/main/java/net/raphimc/viaproxy/proxy/ProxyConnection.java

@@ -179,7 +179,7 @@ public class ProxyConnection extends NetClient {
                     PacketTypes.writeString(disconnectPacketData, channel);
                     PacketTypes.writeVarInt(disconnectPacketData, id);
                     disconnectPacketData.writeBytes(data);
-                    this.c2p.writeAndFlush(new S2CLoginDisconnectPacket(messageToJson("§cYou need to install OpenAuthMod in order to join this server.§k\n" + Base64.getEncoder().encodeToString(ByteBufUtil.getBytes(disconnectPacketData)) + "\n" + CustomPayloadInterface.OPENAUTHMOD_LEGACY_MAGIC_STRING))).addListener(ChannelFutureListener.FIRE_EXCEPTION_ON_FAILURE);
+                    this.c2p.writeAndFlush(new S2CLoginDisconnectPacket(messageToJson("§cYou need to install OpenAuthMod in order to join this server.§k\n" + Base64.getEncoder().encodeToString(ByteBufUtil.getBytes(disconnectPacketData)) + "\n" + ExternalInterface.OPENAUTHMOD_LEGACY_MAGIC_STRING))).addListener(ChannelFutureListener.FIRE_EXCEPTION_ON_FAILURE);
                 }
                 break;
             case PLAY:

src/main/java/net/raphimc/viaproxy/proxy/client2proxy/Client2ProxyHandler.java

@@ -1,7 +1,5 @@
 package net.raphimc.viaproxy.proxy.client2proxy;
 
-import com.github.steveice10.mc.auth.data.GameProfile;
-import com.github.steveice10.mc.auth.util.UUIDSerializer;
 import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
@@ -26,7 +24,6 @@ import net.raphimc.viaproxy.proxy.proxy2server.Proxy2ServerHandler;
 import net.raphimc.viaproxy.proxy.util.CloseAndReturn;
 import net.raphimc.viaproxy.proxy.util.ExceptionUtil;
 import net.raphimc.viaproxy.util.ArrayHelper;
-import net.raphimc.viaproxy.util.LocalSocketClient;
 import net.raphimc.viaproxy.util.logging.Logger;
 
 import javax.crypto.SecretKey;
@@ -34,9 +31,9 @@ import java.math.BigInteger;
 import java.nio.charset.StandardCharsets;
 import java.security.*;
 import java.security.spec.InvalidKeySpecException;
-import java.security.spec.X509EncodedKeySpec;
 import java.time.Instant;
-import java.util.*;
+import java.util.Arrays;
+import java.util.Random;
 import java.util.regex.Pattern;
 
 public class Client2ProxyHandler extends SimpleChannelInboundHandler<IPacket> {
@@ -208,31 +205,17 @@ public class Client2ProxyHandler extends SimpleChannelInboundHandler<IPacket> {
             }
         }
 
-        this.proxyConnection.setLoginHelloPacket(packet);
+        ExternalInterface.fillPlayerData(packet, this.proxyConnection);
-        this.proxyConnection.setGameProfile(new GameProfile((UUID) null, packet.name));
 
         if (Options.ONLINE_MODE) {
             this.proxyConnection.getC2P().writeAndFlush(new S2CLoginKeyPacket1_8("", KEY_PAIR.getPublic().getEncoded(), this.verifyToken)).addListener(ChannelFutureListener.FIRE_EXCEPTION_ON_FAILURE);
         } else {
-            if (Options.LOCAL_SOCKET_AUTH) {
+            this.proxyConnection.getChannel().writeAndFlush(this.proxyConnection.getLoginHelloPacket()).addListener(ChannelFutureListener.FIRE_EXCEPTION_ON_FAILURE);
-                String[] response = new LocalSocketClient(48941).request("getusername");
-                if (response != null && response[0].equals("success")) {
-                    this.proxyConnection.setGameProfile(new GameProfile((UUID) null, response[1]));
-                }
-                response = new LocalSocketClient(48941).request("get_public_key_data");
-                if (response != null && response[0].equals("success")) {
-                    final UUID uuid = UUIDSerializer.fromString(response[1].replaceFirst("(\\p{XDigit}{8})(\\p{XDigit}{4})(\\p{XDigit}{4})(\\p{XDigit}{4})(\\p{XDigit}+)", "$1-$2-$3-$4-$5"));
-                    final PublicKey publicKey = KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(Base64.getDecoder().decode(response[2])));
-                    packet = new C2SLoginHelloPacket1_19_3(packet.name, Instant.ofEpochMilli(Long.parseLong(response[4])), publicKey, Base64.getDecoder().decode(response[3]), uuid);
-                }
-            }
-
-            this.proxyConnection.getChannel().writeAndFlush(packet).addListener(ChannelFutureListener.FIRE_EXCEPTION_ON_FAILURE);
         }
     }
 
     private void handleLoginKey(final C2SLoginKeyPacket1_7 packet) throws GeneralSecurityException, InterruptedException {
-        if (this.proxyConnection.getClientVersion().isOlderThanOrEqualTo(VersionEnum.r1_12_2) && new String(packet.encryptedNonce, StandardCharsets.UTF_8).equals(CustomPayloadInterface.OPENAUTHMOD_DATA_CHANNEL)) { // 1.8-1.12.2 OpenAuthMod response handling
+        if (this.proxyConnection.getClientVersion().isOlderThanOrEqualTo(VersionEnum.r1_12_2) && new String(packet.encryptedNonce, StandardCharsets.UTF_8).equals(ExternalInterface.OPENAUTHMOD_DATA_CHANNEL)) { // 1.8-1.12.2 OpenAuthMod response handling
             final ByteBuf byteBuf = Unpooled.wrappedBuffer(packet.encryptedSecretKey);
             this.proxyConnection.handleCustomPayload(PacketTypes.readVarInt(byteBuf), byteBuf);
             return;
@@ -283,7 +266,7 @@ public class Client2ProxyHandler extends SimpleChannelInboundHandler<IPacket> {
 
     private boolean handlePlayCustomPayload(final ByteBuf packet) {
         final String channel = PacketTypes.readString(packet, Short.MAX_VALUE); // channel
-        if (channel.equals(CustomPayloadInterface.OPENAUTHMOD_DATA_CHANNEL)) {
+        if (channel.equals(ExternalInterface.OPENAUTHMOD_DATA_CHANNEL)) {
             return this.proxyConnection.handleCustomPayload(PacketTypes.readVarInt(packet), packet);
         }
         return false;

src/main/java/net/raphimc/viaproxy/proxy/proxy2server/Proxy2ServerHandler.java

@@ -11,7 +11,7 @@ import net.raphimc.netminecraft.packet.impl.login.*;
 import net.raphimc.vialegacy.protocols.release.protocol1_7_2_5to1_6_4.storage.ProtocolMetadataStorage;
 import net.raphimc.vialegacy.util.VersionEnum;
 import net.raphimc.viaproxy.cli.options.Options;
-import net.raphimc.viaproxy.proxy.CustomPayloadInterface;
+import net.raphimc.viaproxy.proxy.ExternalInterface;
 import net.raphimc.viaproxy.proxy.ProxyConnection;
 import net.raphimc.viaproxy.proxy.util.ExceptionUtil;
 import net.raphimc.viaproxy.util.logging.Logger;
@@ -76,7 +76,7 @@ public class Proxy2ServerHandler extends SimpleChannelInboundHandler<IPacket> {
             auth = this.proxyConnection.getUserConnection().get(ProtocolMetadataStorage.class).authenticate;
         }
         if (auth) {
-            CustomPayloadInterface.joinServer(serverHash, this.proxyConnection);
+            ExternalInterface.joinServer(serverHash, this.proxyConnection);
         }
 
         final byte[] encryptedSecretKey = CryptUtil.encryptData(publicKey, secretKey.getEncoded());
@@ -84,7 +84,7 @@ public class Proxy2ServerHandler extends SimpleChannelInboundHandler<IPacket> {
 
         final C2SLoginKeyPacket1_19_3 loginKey = new C2SLoginKeyPacket1_19_3(encryptedSecretKey, encryptedNonce);
         if (this.proxyConnection.getLoginHelloPacket() instanceof C2SLoginHelloPacket1_19 && ((C2SLoginHelloPacket1_19) this.proxyConnection.getLoginHelloPacket()).key != null) {
-            CustomPayloadInterface.signNonce(packet.nonce, loginKey, this.proxyConnection);
+            ExternalInterface.signNonce(packet.nonce, loginKey, this.proxyConnection);
         }
         this.proxyConnection.getChannel().writeAndFlush(loginKey).addListener(ChannelFutureListener.FIRE_EXCEPTION_ON_FAILURE);
 

src/main/java/net/raphimc/viaproxy/saves/AbstractSave.java

@@ -0,0 +1,21 @@
+package net.raphimc.viaproxy.saves;
+
+import com.google.gson.JsonElement;
+
+public abstract class AbstractSave {
+
+    private final String name;
+
+    public AbstractSave(final String name) {
+        this.name = name;
+    }
+
+    public abstract void load(final JsonElement jsonElement) throws Throwable;
+
+    public abstract JsonElement save() throws Throwable;
+
+    public String getName() {
+        return this.name;
+    }
+
+}

src/main/java/net/raphimc/viaproxy/saves/SaveManager.java

@@ -0,0 +1,76 @@
+package net.raphimc.viaproxy.saves;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonObject;
+import net.lenni0451.reflect.stream.RStream;
+import net.raphimc.viaproxy.saves.impl.AccountsSave;
+import net.raphimc.viaproxy.util.logging.Logger;
+
+import java.io.*;
+
+public class SaveManager {
+
+    private static final File SAVE_FILE = new File("saves.json");
+    private static final Gson GSON = new Gson();
+
+    public final AccountsSave accountsSave = new AccountsSave();
+
+    public SaveManager() {
+        this.load();
+    }
+
+    public void load() {
+        try {
+            if (!SAVE_FILE.exists()) {
+                SAVE_FILE.createNewFile();
+                this.save();
+            }
+
+            final FileReader reader = new FileReader(SAVE_FILE);
+            final JsonObject saveObject = GSON.fromJson(reader, JsonObject.class);
+            reader.close();
+
+            RStream
+                    .of(this)
+                    .fields()
+                    .filter(field -> AbstractSave.class.isAssignableFrom(field.type()))
+                    .forEach(field -> {
+                        final AbstractSave save = field.get();
+                        try {
+                            if (saveObject.has(save.getName())) {
+                                save.load(saveObject.get(save.getName()));
+                            }
+                        } catch (Throwable e) {
+                            Logger.LOGGER.error("Failed to load save " + save.getName(), e);
+                        }
+                    });
+        } catch (Throwable e) {
+            Logger.LOGGER.error("Failed to load saves from file", e);
+        }
+    }
+
+    public void save() {
+        try {
+            final JsonObject saveObject = new JsonObject();
+            RStream
+                    .of(this)
+                    .fields()
+                    .filter(field -> AbstractSave.class.isAssignableFrom(field.type()))
+                    .forEach(field -> {
+                        final AbstractSave save = field.get();
+                        try {
+                            saveObject.add(save.getName(), save.save());
+                        } catch (Throwable e) {
+                            Logger.LOGGER.error("Failed to save save " + save.getName(), e);
+                        }
+                    });
+
+            final FileWriter writer = new FileWriter(SAVE_FILE);
+            GSON.toJson(saveObject, writer);
+            writer.close();
+        } catch (Throwable e) {
+            Logger.LOGGER.error("Failed to save saves to file", e);
+        }
+    }
+
+}

src/main/java/net/raphimc/viaproxy/saves/impl/AccountsSave.java

@@ -0,0 +1,63 @@
+package net.raphimc.viaproxy.saves.impl;
+
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import net.raphimc.mcauth.MinecraftAuth;
+import net.raphimc.mcauth.step.java.StepMCProfile;
+import net.raphimc.mcauth.util.MicrosoftConstants;
+import net.raphimc.viaproxy.saves.AbstractSave;
+import net.raphimc.viaproxy.util.logging.Logger;
+import org.apache.http.impl.client.CloseableHttpClient;
+
+import java.util.*;
+
+public class AccountsSave extends AbstractSave {
+
+    private List<StepMCProfile.MCProfile> accounts = new ArrayList<>();
+
+    public AccountsSave() {
+        super("accounts");
+    }
+
+    @Override
+    public void load(JsonElement jsonElement) throws Exception {
+        this.accounts = new ArrayList<>();
+        for (JsonElement element : jsonElement.getAsJsonArray()) {
+            this.accounts.add(MinecraftAuth.Java.Title.MC_PROFILE.fromJson(element.getAsJsonObject()));
+        }
+    }
+
+    @Override
+    public JsonElement save() {
+        final JsonArray array = new JsonArray();
+        for (StepMCProfile.MCProfile account : this.accounts) {
+            array.add(account.toJson());
+        }
+        return array;
+    }
+
+    public void addAccount(final StepMCProfile.MCProfile profile) {
+        this.accounts.add(profile);
+    }
+
+    public void removeAccount(final StepMCProfile.MCProfile profile) {
+        this.accounts.remove(profile);
+    }
+
+    public void refreshAccounts() {
+        final List<StepMCProfile.MCProfile> accounts = new ArrayList<>();
+        for (StepMCProfile.MCProfile account : this.accounts) {
+            try (final CloseableHttpClient httpClient = MicrosoftConstants.createHttpClient()) {
+                accounts.add(MinecraftAuth.Java.Title.MC_PROFILE.refresh(httpClient, account));
+            } catch (Throwable e) {
+                Logger.LOGGER.error("Failed to refresh account " + account.name() + ", removing it from the list.", e);
+            }
+        }
+        this.accounts = accounts;
+    }
+
+    public List<StepMCProfile.MCProfile> getAccounts() {
+        return Collections.unmodifiableList(this.accounts);
+    }
+
+}

src/main/java/net/raphimc/viaproxy/ui/impl/GeneralTab.java

@@ -94,7 +94,7 @@ public class GeneralTab extends AUITab {
             authMethodLabel.setBounds(10, 200, 400, 20);
             contentPane.add(authMethodLabel);
 
-            this.authMethod = new JComboBox<>(new String[]{"Use OpenAuthMod"});
+            this.authMethod = new JComboBox<>(new String[]{"Use stored account", "Use OpenAuthMod"});
             this.authMethod.setBounds(10, 220, 465, 20);
             contentPane.add(this.authMethod);
         }
@@ -149,7 +149,7 @@ public class GeneralTab extends AUITab {
             final String serverAddress = this.serverAddress.getText();
             final VersionEnum serverVersion = (VersionEnum) this.serverVersion.getSelectedItem();
             final int bindPort = (int) this.bindPort.getValue();
-            final String authMethod = (String) this.authMethod.getSelectedItem();
+            final int authMethod = this.authMethod.getSelectedIndex();
             final boolean betaCraftAuth = this.betaCraftAuth.isSelected();
             final boolean proxyOnlineMode = this.proxyOnlineMode.isSelected();
 
@@ -162,10 +162,14 @@ public class GeneralTab extends AUITab {
                 Options.CONNECT_ADDRESS = hostAndPort.getHost();
                 Options.CONNECT_PORT = hostAndPort.getPortOrDefault(25565);
                 Options.PROTOCOL_VERSION = serverVersion;
-
-                Options.OPENAUTHMOD_AUTH = true;
                 Options.BETACRAFT_AUTH = betaCraftAuth;
 
+                if (authMethod == 0 && Options.MC_ACCOUNT == null && !ViaProxy.saveManager.accountsSave.getAccounts().isEmpty()) {
+                    Options.MC_ACCOUNT = ViaProxy.saveManager.accountsSave.getAccounts().get(0);
+                } else if (authMethod == 1) {
+                    Options.OPENAUTHMOD_AUTH = true;
+                }
+
                 ViaProxy.startProxy();
 
                 SwingUtilities.invokeLater(() -> {

src/main/java/net/raphimc/viaproxy/ui/impl/OnlineModeTab.java

@@ -2,6 +2,8 @@ package net.raphimc.viaproxy.ui.impl;
 
 import net.raphimc.mcauth.MinecraftAuth;
 import net.raphimc.mcauth.step.java.StepMCProfile;
+import net.raphimc.viaproxy.ViaProxy;
+import net.raphimc.viaproxy.cli.options.Options;
 import net.raphimc.viaproxy.ui.AUITab;
 import net.raphimc.viaproxy.ui.ViaProxyUI;
 import net.raphimc.viaproxy.ui.popups.AddAccountPopup;
@@ -30,17 +32,22 @@ public class OnlineModeTab extends AUITab {
             infoLabel.setBounds(10, 10, 500, 20);
             contentPane.add(infoLabel);
         }
+        {
+            JLabel info2Label = new JLabel("You can select the account to use by right clicking it. By default the first one will be used.");
+            info2Label.setBounds(10, 30, 500, 20);
+            contentPane.add(info2Label);
+        }
         {
             JLabel infoLabel = new JLabel("<html>If you change your account frequently, you might want to install <a href=\"\">OpenAuthMod</a> on your</html>");
-            infoLabel.setBounds(10, 40, 500, 20);
+            infoLabel.setBounds(10, 60, 500, 20);
             contentPane.add(infoLabel);
 
             JLabel infoLabel2 = new JLabel("client. This allows ViaProxy to use the account you are logged in with on the client.");
-            infoLabel2.setBounds(10, 60, 500, 20);
+            infoLabel2.setBounds(10, 80, 500, 20);
             contentPane.add(infoLabel2);
 
             JLabel clickRect = new JLabel();
-            clickRect.setBounds(353, 40, 80, 20);
+            clickRect.setBounds(353, 60, 80, 20);
             clickRect.addMouseListener(new MouseAdapter() {
                 @Override
                 public void mouseReleased(MouseEvent e) {
@@ -51,7 +58,7 @@ public class OnlineModeTab extends AUITab {
         }
         {
             JScrollPane scrollPane = new JScrollPane();
-            scrollPane.setBounds(10, 85, 465, 205);
+            scrollPane.setBounds(10, 105, 465, 185);
             contentPane.add(scrollPane);
 
             DefaultListModel<String> model = new DefaultListModel<>();
@@ -59,12 +66,31 @@ public class OnlineModeTab extends AUITab {
             scrollPane.setViewportView(this.accountsList);
 
             JPopupMenu contextMenu = new JPopupMenu();
+            JMenuItem selectItem = new JMenuItem("Use to join online mode servers");
+            selectItem.addActionListener(e -> {
+                int index = this.accountsList.getSelectedIndex();
+                if (index != -1) {
+                    final StepMCProfile.MCProfile account = ViaProxy.saveManager.accountsSave.getAccounts().get(index);
+                    if (account != null) {
+                        Options.MC_ACCOUNT = account;
+                    } else {
+                        throw new IllegalStateException("Account is null");
+                    }
+                }
+            });
+            contextMenu.add(selectItem);
             JMenuItem removeItem = new JMenuItem("Remove");
             removeItem.addActionListener(e -> {
                 int index = this.accountsList.getSelectedIndex();
                 if (index != -1) {
                     model.remove(index);
-                    //TODO: Remove from save
+                    final StepMCProfile.MCProfile account = ViaProxy.saveManager.accountsSave.getAccounts().get(index);
+                    if (account != null) {
+                        ViaProxy.saveManager.accountsSave.removeAccount(account);
+                        ViaProxy.saveManager.save();
+                    } else {
+                        throw new IllegalStateException("Account is null");
+                    }
                 }
                 if (index < model.getSize()) this.accountsList.setSelectedIndex(index);
                 else if (index > 0) this.accountsList.setSelectedIndex(index - 1);
@@ -89,10 +115,11 @@ public class OnlineModeTab extends AUITab {
                         });
                         SwingUtilities.invokeLater(() -> {
                             this.closePopup();
+                            ViaProxy.saveManager.accountsSave.addAccount(profile);
+                            ViaProxy.saveManager.save();
                             DefaultListModel<String> model = (DefaultListModel<String>) this.accountsList.getModel();
                             model.addElement(profile.name());
                             this.frame.showInfo("The account " + profile.name() + " was added successfully.");
-                            //TODO: Add to save
                         });
                     } catch (InterruptedException ignored) {
                     } catch (TimeoutException e) {
@@ -114,6 +141,12 @@ public class OnlineModeTab extends AUITab {
         }
     }
 
+    @Override
+    public void setReady() {
+        final DefaultListModel<String> model = (DefaultListModel<String>) this.accountsList.getModel();
+        ViaProxy.saveManager.accountsSave.getAccounts().forEach(account -> model.addElement(account.name()));
+    }
+
     private void closePopup() {
         this.addAccountPopup.markExternalClose();
         this.addAccountPopup.setVisible(false);