Paper/patches/unapplied/server/0777-Validate-usernames.patch
2023-03-14 18:11:24 +01:00

71 lines
3.7 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Sat, 1 Jan 2022 05:19:37 -0800
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 b6dc42aef6458b0c09007bb0e13048b99531f8c0..7e8401a05905775f7209abb1269e24aad409af50 100644
--- a/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
@@ -60,6 +60,7 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
private final String serverId;
@Nullable
private ServerPlayer delayedAcceptPlayer;
+ public boolean iKnowThisMayNotBeTheBestIdeaButPleaseDisableUsernameValidation = false; // Paper - username validation overriding
public ServerLoginPacketListenerImpl(MinecraftServer server, Connection connection) {
this.state = ServerLoginPacketListenerImpl.State.HELLO;
@@ -212,10 +213,38 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener,
// Paper end
}
+ // 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(ServerLoginPacketListenerImpl.isValidUsername(packet.name()), "Invalid characters in username", new Object[0]);
+ // Paper start - validate usernames
+ 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
GameProfile gameprofile = this.server.getSingleplayerProfile();
if (gameprofile != null && packet.name().equalsIgnoreCase(gameprofile.getName())) {
diff --git a/src/main/java/net/minecraft/server/players/PlayerList.java b/src/main/java/net/minecraft/server/players/PlayerList.java
index d396e2cb91aa99d60c898f86e0f33d3ce3f885cd..147d955d8be63255ff74457c2c3b92cd22577342 100644
--- a/src/main/java/net/minecraft/server/players/PlayerList.java
+++ b/src/main/java/net/minecraft/server/players/PlayerList.java
@@ -652,7 +652,7 @@ public abstract class PlayerList {
for (int i = 0; i < this.players.size(); ++i) {
entityplayer = (ServerPlayer) this.players.get(i);
- if (entityplayer.getUUID().equals(uuid)) {
+ if (entityplayer.getUUID().equals(uuid) || (io.papermc.paper.configuration.GlobalConfiguration.get().proxies.isProxyOnlineMode() && entityplayer.getGameProfile().getName().equalsIgnoreCase(gameprofile.getName()))) { // Paper - validate usernames
list.add(entityplayer);
}
}