From f97405604deef438f759a05ad18037a66e15eff5 Mon Sep 17 00:00:00 2001
From: RaphiMC <50594595+RaphiMC@users.noreply.github.com>
Date: Thu, 2 Nov 2023 19:30:46 +0100
Subject: [PATCH] Added event to skip Mojang auth

---
 .../plugins/events/PreMojangAuthEvent.java    | 35 +++++++++++++++++++
 .../packethandler/LoginPacketHandler.java     | 28 ++++++++-------
 2 files changed, 50 insertions(+), 13 deletions(-)
 create mode 100644 src/main/java/net/raphimc/viaproxy/plugins/events/PreMojangAuthEvent.java

diff --git a/src/main/java/net/raphimc/viaproxy/plugins/events/PreMojangAuthEvent.java b/src/main/java/net/raphimc/viaproxy/plugins/events/PreMojangAuthEvent.java
new file mode 100644
index 00000000..e8fd357d
--- /dev/null
+++ b/src/main/java/net/raphimc/viaproxy/plugins/events/PreMojangAuthEvent.java
@@ -0,0 +1,35 @@
+/*
+ * This file is part of ViaProxy - https://github.com/RaphiMC/ViaProxy
+ * Copyright (C) 2023 RK_01/RaphiMC and contributors
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+package net.raphimc.viaproxy.plugins.events;
+
+import net.raphimc.viaproxy.plugins.events.types.EventCancellable;
+import net.raphimc.viaproxy.proxy.session.ProxyConnection;
+
+public class PreMojangAuthEvent extends EventCancellable {
+
+    private final ProxyConnection proxyConnection;
+
+    public PreMojangAuthEvent(final ProxyConnection proxyConnection) {
+        this.proxyConnection = proxyConnection;
+    }
+
+    public ProxyConnection getProxyConnection() {
+        return this.proxyConnection;
+    }
+
+}
diff --git a/src/main/java/net/raphimc/viaproxy/proxy/packethandler/LoginPacketHandler.java b/src/main/java/net/raphimc/viaproxy/proxy/packethandler/LoginPacketHandler.java
index 91e14e52..a561d635 100644
--- a/src/main/java/net/raphimc/viaproxy/proxy/packethandler/LoginPacketHandler.java
+++ b/src/main/java/net/raphimc/viaproxy/proxy/packethandler/LoginPacketHandler.java
@@ -32,6 +32,7 @@
 import net.raphimc.viaproxy.cli.options.Options;
 import net.raphimc.viaproxy.plugins.PluginManager;
 import net.raphimc.viaproxy.plugins.events.ClientLoggedInEvent;
+import net.raphimc.viaproxy.plugins.events.PreMojangAuthEvent;
 import net.raphimc.viaproxy.proxy.LoginState;
 import net.raphimc.viaproxy.proxy.external_interface.AuthLibServices;
 import net.raphimc.viaproxy.proxy.external_interface.ExternalInterface;
@@ -121,20 +122,21 @@ public boolean handleC2P(IPacket packet, List<ChannelFutureListener> listeners)
             final SecretKey secretKey = CryptUtil.decryptSecretKey(KEY_PAIR.getPrivate(), loginKeyPacket.encryptedSecretKey);
             this.proxyConnection.getC2P().attr(MCPipeline.ENCRYPTION_ATTRIBUTE_KEY).set(new AESEncryption(secretKey));
 
-            final String userName = this.proxyConnection.getGameProfile().getName();
-
-            try {
-                final String serverHash = new BigInteger(CryptUtil.computeServerIdHash("", KEY_PAIR.getPublic(), secretKey)).toString(16);
-                final GameProfile mojangProfile = AuthLibServices.SESSION_SERVICE.hasJoinedServer(this.proxyConnection.getGameProfile(), serverHash, null);
-                if (mojangProfile == null) {
-                    Logger.u_err("auth", this.proxyConnection.getC2P().remoteAddress(), this.proxyConnection.getGameProfile(), "Invalid session");
-                    this.proxyConnection.kickClient("§cInvalid session! Please restart minecraft (and the launcher) and try again.");
-                } else {
-                    this.proxyConnection.setGameProfile(mojangProfile);
+            if (!PluginManager.EVENT_MANAGER.call(new PreMojangAuthEvent(this.proxyConnection)).isCancelled()) {
+                final String userName = this.proxyConnection.getGameProfile().getName();
+                try {
+                    final String serverHash = new BigInteger(CryptUtil.computeServerIdHash("", KEY_PAIR.getPublic(), secretKey)).toString(16);
+                    final GameProfile mojangProfile = AuthLibServices.SESSION_SERVICE.hasJoinedServer(this.proxyConnection.getGameProfile(), serverHash, null);
+                    if (mojangProfile == null) {
+                        Logger.u_err("auth", this.proxyConnection.getC2P().remoteAddress(), this.proxyConnection.getGameProfile(), "Invalid session");
+                        this.proxyConnection.kickClient("§cInvalid session! Please restart minecraft (and the launcher) and try again.");
+                    } else {
+                        this.proxyConnection.setGameProfile(mojangProfile);
+                    }
+                    Logger.u_info("auth", this.proxyConnection.getC2P().remoteAddress(), this.proxyConnection.getGameProfile(), "Authenticated as " + this.proxyConnection.getGameProfile().getId().toString());
+                } catch (Throwable e) {
+                    throw new RuntimeException("Failed to make session request for user '" + userName + "'!", e);
                 }
-                Logger.u_info("auth", this.proxyConnection.getC2P().remoteAddress(), this.proxyConnection.getGameProfile(), "Authenticated as " + this.proxyConnection.getGameProfile().getId().toString());
-            } catch (Throwable e) {
-                throw new RuntimeException("Failed to make session request for user '" + userName + "'!", e);
             }
 
             PluginManager.EVENT_MANAGER.call(new ClientLoggedInEvent(proxyConnection));