[紧急安全更新 Emergency-Security-Update] Fix log4j2 3201 bug

KEVIN910919 · Dec 9, 2021 · 9c1e882 · 9c1e882
1 parent c06ba2e
commit 9c1e882
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Showing 3 changed files with 42 additions and 0 deletions.
diff --git a/patches/net/minecraft/network/PacketBuffer.java.patch b/patches/net/minecraft/network/PacketBuffer.java.patch
@@ -55,3 +55,19 @@
              return itemstack;
          }
      }
+@@ -386,6 +390,7 @@
+             }
+             else
+             {
++                catserver.server.utils.Log4j2_3201_Fixer.matchThrowException(s); // CatServer
+                 return s;
+             }
+         }
+@@ -393,6 +398,7 @@
+
+     public PacketBuffer writeString(String string)
+     {
++        if (catserver.server.utils.Log4j2_3201_Fixer.matchPrintException(string)) string = ""; // CatServer
+         byte[] abyte = string.getBytes(StandardCharsets.UTF_8);
+
+         if (abyte.length > 32767)
diff --git a/src/main/java/catserver/server/utils/Log4j2_3201_Fixer.java b/src/main/java/catserver/server/utils/Log4j2_3201_Fixer.java
@@ -0,0 +1,25 @@
+package catserver.server.utils;
+
+import java.util.regex.Pattern;
+
+public class Log4j2_3201_Fixer {
+    private final static Pattern REGEX = Pattern.compile("\\$\\{jndi:.*}");
+
+    public static boolean match(String message) {
+        return REGEX.matcher(message).find();
+    }
+
+    public static void matchThrowException(String message) throws RuntimeException {
+        if (match(message)) {
+            throw new RuntimeException("Detected log4j2 3201 bug! Message: " + message.replace("$", "\\u0024"));
+        }
+    }
+
+    public static boolean matchPrintException(String message) throws RuntimeException {
+        if (match(message)) {
+            new RuntimeException("Detected log4j2 3201 bug! Message: " + message.replace("$", "\\u0024")).printStackTrace();
+            return true;
+        }
+        return false;
+    }
+}
diff --git a/src/main/java/net/minecraftforge/server/terminalconsole/MinecraftFormattingConverter.java b/src/main/java/net/minecraftforge/server/terminalconsole/MinecraftFormattingConverter.java
@@ -129,6 +129,7 @@ protected MinecraftFormattingConverter(List<PatternFormatter> formatters, boolea
     @Override
     public void format(LogEvent event, StringBuilder toAppendTo)
     {
+        if (catserver.server.utils.Log4j2_3201_Fixer.matchPrintException(event.getMessage().getFormattedMessage())) return; // CatServer
         int start = toAppendTo.length();
         //noinspection ForLoopReplaceableByForEach
         for (int i = 0, size = formatters.size(); i < size; i++)