Paper/patches/server/0822-Validate-usernames.patch

71 lines
3.8 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 dcabb783bed9160f7d602d551cf7e8d004abbca1..e581656c4450be708f1a91a42b5b1da9105df6f3 100644
--- a/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerLoginPacketListenerImpl.java
@@ -70,6 +70,7 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener
private ProfilePublicKey playerProfilePublicKey;
public String hostname = ""; // CraftBukkit - add field
private int velocityLoginMessageId = -1; // Paper - Velocity support
+ public boolean iKnowThisMayNotBeTheBestIdeaButPleaseDisableUsernameValidation = false; // Paper - username validation overriding
public ServerLoginPacketListenerImpl(MinecraftServer server, Connection connection) {
this.state = ServerLoginPacketListenerImpl.State.HELLO;
@@ -262,10 +263,38 @@ public class ServerLoginPacketListenerImpl implements ServerLoginPacketListener
}
}
+ // 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
try {
this.playerProfilePublicKey = ServerLoginPacketListenerImpl.validatePublicKey(packet, this.server.getServiceSignatureValidator(), this.server.enforceSecureProfile());
diff --git a/src/main/java/net/minecraft/server/players/PlayerList.java b/src/main/java/net/minecraft/server/players/PlayerList.java
index 6d013360d35c54d1493849b22c9d65b18147cc33..c0ed1103e649e619c58f59c7bedd6a18a58f71ea 100644
--- a/src/main/java/net/minecraft/server/players/PlayerList.java
+++ b/src/main/java/net/minecraft/server/players/PlayerList.java
@@ -707,7 +707,7 @@ 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);
}
}