From 1e5f3471699840ab11eed101c5ea38cc5f53600c Mon Sep 17 00:00:00 2001
From: Owen1212055 <23108066+Owen1212055@users.noreply.github.com>
Date: Wed, 6 Dec 2023 20:26:58 -0500
Subject: [PATCH] Clean up username validation logic

---
 patches/server/Validate-usernames.patch | 65 +++++++++++++------------
 1 file changed, 33 insertions(+), 32 deletions(-)

diff --git a/patches/server/Validate-usernames.patch b/patches/server/Validate-usernames.patch
index 26dd83291a..fcc7c1165c 100644
--- a/patches/server/Validate-usernames.patch
+++ b/patches/server/Validate-usernames.patch
@@ -17,41 +17,11 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
      public ServerLoginPacketListenerImpl(MinecraftServer server, Connection connection) {
          this.state = ServerLoginPacketListenerImpl.State.HELLO;
 @@ -0,0 +0,0 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
-         return this.requestedUsername != null ? this.requestedUsername + " (" + s + ")" : s;
-     }
- 
-+    // Paper start - validate usernames
-+    public static boolean validateUsername(String in) {
-+        if (in == null || in.isEmpty() || in.length() > 16) {
-+            return false;
-+        }
-+
-+        for (int i = 0, len = in.length(); i < len; ++i) {
-+            char c = in.charAt(i);
-+
-+            if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || (c == '_' || c == '.')) {
-+                continue;
-+            }
-+
-+            return false;
-+        }
-+
-+        return true;
-+    }
-+    // Paper end - validate usernames
-+
      @Override
      public void handleHello(ServerboundHelloPacket packet) {
          Validate.validState(this.state == ServerLoginPacketListenerImpl.State.HELLO, "Unexpected hello packet", new Object[0]);
-         Validate.validState(Player.isValidUsername(packet.name()), "Invalid characters in username", new Object[0]);
-+        // Paper start - validate usernames -- TODO: Do we need this?
-+        if (io.papermc.paper.configuration.GlobalConfiguration.get().proxies.isProxyOnlineMode() && io.papermc.paper.configuration.GlobalConfiguration.get().unsupportedSettings.performUsernameValidation) {
-+            if (!this.iKnowThisMayNotBeTheBestIdeaButPleaseDisableUsernameValidation && !validateUsername(packet.name())) {
-+                ServerLoginPacketListenerImpl.this.disconnect("Failed to verify username!");
-+                return;
-+            }
-+        }
-+        // Paper end - validate usernames
+-        Validate.validState(Player.isValidUsername(packet.name()), "Invalid characters in username", new Object[0]);
++        if (io.papermc.paper.configuration.GlobalConfiguration.get().proxies.isProxyOnlineMode() && io.papermc.paper.configuration.GlobalConfiguration.get().unsupportedSettings.performUsernameValidation && !this.iKnowThisMayNotBeTheBestIdeaButPleaseDisableUsernameValidation) Validate.validState(Player.isValidUsername(packet.name()), "Invalid characters in username", new Object[0]); // Paper - config username validation
          this.requestedUsername = packet.name();
          GameProfile gameprofile = this.server.getSingleplayerProfile();
  
@@ -68,3 +38,34 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
                  list.add(entityplayer);
              }
          }
+diff --git a/src/main/java/net/minecraft/world/entity/player/Player.java b/src/main/java/net/minecraft/world/entity/player/Player.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/net/minecraft/world/entity/player/Player.java
++++ b/src/main/java/net/minecraft/world/entity/player/Player.java
+@@ -0,0 +0,0 @@ public abstract class Player extends LivingEntity {
+     }
+ 
+     public static boolean isValidUsername(String name) {
+-        return name.length() > 16 ? false : name.chars().filter((i) -> {
+-            return i <= 32 || i >= 127;
+-        }).findAny().isEmpty();
++        // Paper start
++        if (name == null || name.isEmpty() || name.length() > 16) {
++            return false;
++        }
++
++        for (int i = 0, len = name.length(); i < len; ++i) {
++            char c = name.charAt(i);
++
++            if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || (c == '_' || c == '.')) {
++                continue;
++            }
++
++            return false;
++        }
++
++        return true;
++        // Paper end
+     }
+ 
+     public static float getPickRange(boolean creative) {