Scissors/patches/server/0053-Add-depth-limit-to-Component-deserializer.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Luna <lunahatesgogle@gmail.com>
Date: Wed, 31 May 2023 20:44:20 -0300
Subject: [PATCH] Add depth limit to Component deserializer


diff --git a/src/main/java/com/github/atlasmediagroup/scissors/ScissorsConfig.java b/src/main/java/com/github/atlasmediagroup/scissors/ScissorsConfig.java
index bb58d90e9d676761a43a12cbc1c3b687d00654b1..74f33cba7d713eddca5a58a2b33cad357792145e 100644
--- a/src/main/java/com/github/atlasmediagroup/scissors/ScissorsConfig.java
+++ b/src/main/java/com/github/atlasmediagroup/scissors/ScissorsConfig.java
@@ -65,8 +65,8 @@ public class ScissorsConfig
         config.options().header(HEADER);
         config.options().copyDefaults(true);
 
-        version = getInt("config-version", 3);
-        set("config-version", 3);
+        version = getInt("config-version", 4);
+        set("config-version", 4);
         readConfig(ScissorsConfig.class, null);
     }
 
@@ -146,6 +146,12 @@ public class ScissorsConfig
         disableGameMasterBlocks = getBoolean("disableGameMasterBlocks", false);
     }
 
+    public static int componentDepthLimit = 128;
+    private static void componentDepthLimit()
+    {
+        componentDepthLimit = getInt("componentDepthLimit", 128);
+    }
+
     private static void set(String path, Object val)
     {
         config.set(path, val);
diff --git a/src/main/java/net/minecraft/network/chat/Component.java b/src/main/java/net/minecraft/network/chat/Component.java
index 474ed00c09d58a7796cd543c9bcf8752e2f9f742..68e99223b0b084bdfdb9990780150bbc7d8ad8ea 100644
--- a/src/main/java/net/minecraft/network/chat/Component.java
+++ b/src/main/java/net/minecraft/network/chat/Component.java
@@ -1,5 +1,6 @@
 package net.minecraft.network.chat;
 
+import com.github.atlasmediagroup.scissors.ScissorsConfig; // Scissors
 import com.google.common.collect.Lists;
 import io.papermc.paper.adventure.AdventureComponent; // Paper
 import com.google.gson.Gson;
@@ -33,6 +34,7 @@ import net.minecraft.util.GsonHelper;
 import net.minecraft.util.LowerCaseEnumTypeAdapterFactory;
 // CraftBukkit start
 import com.google.common.collect.Streams;
+import java.util.regex.Pattern; // Scissors
 import java.util.stream.Stream;
 // CraftBukkit end
 
@@ -192,27 +194,31 @@ public interface Component extends Message, FormattedText, Iterable<Component> {
                 throw new IllegalStateException("Couldn't get field 'lineStart' for JsonReader", nosuchfieldexception);
             }
         });
+        private static final Pattern PLACEHOLDER_PATTERN = Pattern.compile("%[0-9]+\\$s"); // Scissors
 
         public Serializer() {}
 
-        public MutableComponent deserialize(JsonElement jsonelement, Type type, JsonDeserializationContext jsondeserializationcontext) throws JsonParseException {
+        // Scissors start
+        private MutableComponent deserialize(JsonElement jsonelement, JsonDeserializationContext jsondeserializationcontext, int depth) throws JsonParseException {
+            if (depth > ScissorsConfig.componentDepthLimit) {
+                throw new JsonParseException("Depth limit exceeded");
+            }
+
             if (jsonelement.isJsonPrimitive()) {
                 return new TextComponent(jsonelement.getAsString());
             } else if (!jsonelement.isJsonObject()) {
                 if (jsonelement.isJsonArray()) {
                     JsonArray jsonarray = jsonelement.getAsJsonArray();
-                    // Scissors start
                     if (jsonarray.size() <= 0) {
                         throw new JsonParseException("Unexpected empty array of components");
                     }
-                    // Scissors end
                     
                     MutableComponent ichatmutablecomponent = null;
                     Iterator iterator = jsonarray.iterator();
 
                     while (iterator.hasNext()) {
                         JsonElement jsonelement1 = (JsonElement) iterator.next();
-                        MutableComponent ichatmutablecomponent1 = this.deserialize(jsonelement1, jsonelement1.getClass(), jsondeserializationcontext);
+                        MutableComponent ichatmutablecomponent1 = this.deserialize(jsonelement1, jsondeserializationcontext, depth + 1);
 
                         if (ichatmutablecomponent == null) {
                             ichatmutablecomponent = ichatmutablecomponent1;
@@ -236,12 +242,17 @@ public interface Component extends Message, FormattedText, Iterable<Component> {
 
                     if (jsonobject.has("translate")) {
                         s = GsonHelper.getAsString(jsonobject, "translate");
+ 
+                        // Penalize depth for placeholders in translate & fallback
+                        long translate_placeholders = PLACEHOLDER_PATTERN.matcher(s).results().count();
+                        int penalty = (int)translate_placeholders * 12;
+
                         if (jsonobject.has("with")) {
                             JsonArray jsonarray1 = GsonHelper.getAsJsonArray(jsonobject, "with");
                             Object[] aobject = new Object[jsonarray1.size()];
 
                             for (int i = 0; i < aobject.length; ++i) {
-                                aobject[i] = this.deserialize(jsonarray1.get(i), type, jsondeserializationcontext);
+                                aobject[i] = this.deserialize(jsonarray1.get(i), jsondeserializationcontext, depth + 1 + penalty);
                                 if (aobject[i] instanceof TextComponent) {
                                     TextComponent chatcomponenttext = (TextComponent) aobject[i];
 
@@ -264,7 +275,7 @@ public interface Component extends Message, FormattedText, Iterable<Component> {
 
                         object = new ScoreComponent(GsonHelper.getAsString(jsonobject1, "name"), GsonHelper.getAsString(jsonobject1, "objective"));
                     } else if (jsonobject.has("selector")) {
-                        Optional<Component> optional = this.parseSeparator(type, jsondeserializationcontext, jsonobject);
+                        Optional<Component> optional = this.parseSeparator(jsondeserializationcontext, jsonobject, depth + 1);
 
                         object = new SelectorComponent(GsonHelper.getAsString(jsonobject, "selector"), optional);
                     } else if (jsonobject.has("keybind")) {
@@ -275,7 +286,7 @@ public interface Component extends Message, FormattedText, Iterable<Component> {
                         }
 
                         s = GsonHelper.getAsString(jsonobject, "nbt");
-                        Optional<Component> optional1 = this.parseSeparator(type, jsondeserializationcontext, jsonobject);
+                        Optional<Component> optional1 = this.parseSeparator(jsondeserializationcontext, jsonobject, depth + 1);
                         boolean flag = GsonHelper.getAsBoolean(jsonobject, "interpret", false);
 
                         if (jsonobject.has("block")) {
@@ -300,7 +311,7 @@ public interface Component extends Message, FormattedText, Iterable<Component> {
                     }
 
                     for (int j = 0; j < jsonarray2.size(); ++j) {
-                        ((MutableComponent) object).append(this.deserialize(jsonarray2.get(j), type, jsondeserializationcontext));
+                        ((MutableComponent) object).append(this.deserialize(jsonarray2.get(j), jsondeserializationcontext, depth + 1));
                     }
                 }
 
@@ -309,8 +320,13 @@ public interface Component extends Message, FormattedText, Iterable<Component> {
             }
         }
 
-        private Optional<Component> parseSeparator(Type type, JsonDeserializationContext context, JsonObject json) {
-            return json.has("separator") ? Optional.of(this.deserialize(json.get("separator"), type, context)) : Optional.empty();
+        public MutableComponent deserialize(JsonElement jsonelement, Type type, JsonDeserializationContext jsondeserializationcontext) throws JsonParseException {
+            return this.deserialize(jsonelement, jsondeserializationcontext, 1);
+        }
+
+        private Optional<Component> parseSeparator(JsonDeserializationContext context, JsonObject json, int depth) {
+            return json.has("separator") ? Optional.of(this.deserialize(json.get("separator"), context, depth + 1)) : Optional.empty();
+            // Scissors end
         }
 
         private void serializeStyle(Style style, JsonObject json, JsonSerializationContext context) {