Fix overly strong name validation in player heads

Closes #10477

3 files changed, 27 insertions, 20 deletions

diff --git a/patches/server/0663-Validate-usernames.patch b/patches/server/0663-Validate-usernames.patch
index 51eedf4f14..d3b04f3950 100644
--- a/patches/server/0663-Validate-usernames.patch
+++ b/patches/server/0663-Validate-usernames.patch
@@ -5,7 +5,7 @@ Subject: [PATCH] Validate usernames
 
 
 diff --git a/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
-index b968026728b8b4e549eed9fa9b43919c6c19eb7a..c44a15fc358c28345302b1bf37fc4b111a77fe0e 100644
+index b968026728b8b4e549eed9fa9b43919c6c19eb7a..9bcded0466f3b10fafd709edc44c60f85cb48b7f 100644
 --- a/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
 +++ b/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
 @@ -83,6 +83,7 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
@@ -16,12 +16,18 @@ index b968026728b8b4e549eed9fa9b43919c6c19eb7a..c44a15fc358c28345302b1bf37fc4b11
  
      public ServerLoginPacketListenerImpl(MinecraftServer server, Connection connection, boolean transferred) {
          this.state = ServerLoginPacketListenerImpl.State.HELLO;
-@@ -164,7 +165,7 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
+@@ -164,7 +165,13 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
      @Override
      public void handleHello(ServerboundHelloPacket packet) {
          Validate.validState(this.state == ServerLoginPacketListenerImpl.State.HELLO, "Unexpected hello packet", new Object[0]);
 -        Validate.validState(StringUtil.isValidPlayerName(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(StringUtil.isValidPlayerName(packet.name()), "Invalid characters in username", new Object[0]); // Paper - config username validation
++        // Paper start - Validate usernames
++        if (io.papermc.paper.configuration.GlobalConfiguration.get().proxies.isProxyOnlineMode()
++            && io.papermc.paper.configuration.GlobalConfiguration.get().unsupportedSettings.performUsernameValidation
++            && !this.iKnowThisMayNotBeTheBestIdeaButPleaseDisableUsernameValidation) {
++            Validate.validState(StringUtil.isReasonablePlayerName(packet.name()), "Invalid characters in username", new Object[0]);
++        }
++        // Paper end - Validate usernames
          this.requestedUsername = packet.name();
          GameProfile gameprofile = this.server.getSingleplayerProfile();
  
@@ -39,22 +45,21 @@ index d7bbdcc97745246718c92c9aba56d9f926897975..7406784899ba5f3575adf1ffe5e5d85a
              }
          }
 diff --git a/src/main/java/net/minecraft/util/StringUtil.java b/src/main/java/net/minecraft/util/StringUtil.java
-index d3fc549a08993376c76c4ebebb788fea3f4ddf69..ae7ef47446c15b8a6878dd2d31b60cd0670eaf83 100644
+index d3fc549a08993376c76c4ebebb788fea3f4ddf69..0bd191acb9596d3aa21c337230d26f09d26f6888 100644
 --- a/src/main/java/net/minecraft/util/StringUtil.java
 +++ b/src/main/java/net/minecraft/util/StringUtil.java
-@@ -64,7 +64,23 @@ public class StringUtil {
+@@ -67,6 +67,25 @@ public class StringUtil {
+         return name.length() <= 16 && name.chars().filter(c -> c <= 32 || c >= 127).findAny().isEmpty();
      }
  
-     public static boolean isValidPlayerName(String name) {
--        return name.length() <= 16 && name.chars().filter(c -> c <= 32 || c >= 127).findAny().isEmpty();
-+        // Paper start - username validation overriding
-+        if (name == null || name.isEmpty() || name.length() > 16) {
++    // Paper start - Username validation
++    public static boolean isReasonablePlayerName(final String name) {
++        if (name.isEmpty() || name.length() > 16) {
 +            return false;
 +        }
 +
 +        for (int i = 0, len = name.length(); i < len; ++i) {
-+            char c = name.charAt(i);
-+
++            final char c = name.charAt(i);
 +            if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || (c == '_' || c == '.')) {
 +                continue;
 +            }
@@ -63,7 +68,9 @@ index d3fc549a08993376c76c4ebebb788fea3f4ddf69..ae7ef47446c15b8a6878dd2d31b60cd0
 +        }
 +
 +        return true;
-+        // Paper end - username validation overriding
-     }
- 
++    }
++    // Paper end - Username validation
++
      public static String filterText(String string) {
+         return filterText(string, false);
+     }
diff --git a/patches/server/0752-Add-Velocity-IP-Forwarding-Support.patch b/patches/server/0752-Add-Velocity-IP-Forwarding-Support.patch
index 0987d6a956..717824d206 100644
--- a/patches/server/0752-Add-Velocity-IP-Forwarding-Support.patch
+++ b/patches/server/0752-Add-Velocity-IP-Forwarding-Support.patch
@@ -134,7 +134,7 @@ index 784788d8d3d1a07efbd406b6c463e046699081e2..fdff82ed5dbf5176d470b9b6c41acfe6
                  DedicatedServer.LOGGER.warn("While this makes the game possible to play without internet access, it also opens up the ability for hackers to connect with any username they choose.");
              }
 diff --git a/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
-index c44a15fc358c28345302b1bf37fc4b111a77fe0e..3333cb70744dc7ef8b181d332b63766aaaaad11f 100644
+index 9bcded0466f3b10fafd709edc44c60f85cb48b7f..cb006ae0e5be2f1d31261bdd36964229ec44416d 100644
 --- a/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
 +++ b/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
 @@ -84,6 +84,7 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
@@ -145,7 +145,7 @@ index c44a15fc358c28345302b1bf37fc4b111a77fe0e..3333cb70744dc7ef8b181d332b63766a
  
      public ServerLoginPacketListenerImpl(MinecraftServer server, Connection connection, boolean transferred) {
          this.state = ServerLoginPacketListenerImpl.State.HELLO;
-@@ -176,6 +177,16 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
+@@ -182,6 +183,16 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
                  this.state = ServerLoginPacketListenerImpl.State.KEY;
                  this.connection.send(new ClientboundHelloPacket("", this.server.getKeyPair().getPublic().getEncoded(), this.challenge, true));
              } else {
@@ -162,7 +162,7 @@ index c44a15fc358c28345302b1bf37fc4b111a77fe0e..3333cb70744dc7ef8b181d332b63766a
                  // CraftBukkit start
                  // Paper start - Cache authenticator threads
                  authenticatorPool.execute(new Runnable() {
-@@ -328,6 +339,12 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
+@@ -334,6 +345,12 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
  
      // CraftBukkit start
      private GameProfile callPlayerPreLoginEvents(GameProfile gameprofile) throws Exception { // Paper - Add more fields to AsyncPlayerPreLoginEvent
@@ -175,7 +175,7 @@ index c44a15fc358c28345302b1bf37fc4b111a77fe0e..3333cb70744dc7ef8b181d332b63766a
          String playerName = gameprofile.getName();
          java.net.InetAddress address = ((java.net.InetSocketAddress) this.connection.getRemoteAddress()).getAddress();
          java.util.UUID uniqueId = gameprofile.getId();
-@@ -373,6 +390,51 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
+@@ -379,6 +396,51 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
  
      @Override
      public void handleCustomQueryPacket(ServerboundCustomQueryAnswerPacket packet) {
diff --git a/patches/server/1011-Use-Velocity-compression-and-cipher-natives.patch b/patches/server/1011-Use-Velocity-compression-and-cipher-natives.patch
index 659e02628d..95f9b5544d 100644
--- a/patches/server/1011-Use-Velocity-compression-and-cipher-natives.patch
+++ b/patches/server/1011-Use-Velocity-compression-and-cipher-natives.patch
@@ -352,10 +352,10 @@ index a08d9aa6e420f691795df9b627a9cd5b5c0112c5..52f537b7bfbdeaad9d17c0e88a1ed1c8
                  protected void initChannel(Channel channel) {
                      try {
 diff --git a/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
-index 3333cb70744dc7ef8b181d332b63766aaaaad11f..765cf12c1558afd9686793b18388fc229c55d2d8 100644
+index cb006ae0e5be2f1d31261bdd36964229ec44416d..b656741eb68adeb04bf995f1045902cb6bd5f2e7 100644
 --- a/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
 +++ b/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
-@@ -274,12 +274,14 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
+@@ -280,12 +280,14 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
              }
  
              SecretKey secretkey = packet.getSecretKey(privatekey);