From 540d970a4d59faeee5c7c2e6e417254b5ed37b46 Mon Sep 17 00:00:00 2001
From: Andrew Steinborn <git@steinborn.me>
Date: Tue, 6 Jul 2021 07:32:13 +0000
Subject: [PATCH] Minecraft 1.17.1 support (#530)

---
 .../api/network/ProtocolVersion.java          |  3 +-
 .../com/velocitypowered/proxy/Velocity.java   | 11 ------
 .../netty/MinecraftCompressDecoder.java       |  2 +-
 .../MinecraftCompressorAndLengthEncoder.java  | 35 ++-----------------
 4 files changed, 6 insertions(+), 45 deletions(-)

diff --git a/api/src/main/java/com/velocitypowered/api/network/ProtocolVersion.java b/api/src/main/java/com/velocitypowered/api/network/ProtocolVersion.java
index 0bbdc45bb..bdddd586d 100644
--- a/api/src/main/java/com/velocitypowered/api/network/ProtocolVersion.java
+++ b/api/src/main/java/com/velocitypowered/api/network/ProtocolVersion.java
@@ -54,7 +54,8 @@ public enum ProtocolVersion {
   MINECRAFT_1_16_2(751, "1.16.2"),
   MINECRAFT_1_16_3(753, "1.16.3"),
   MINECRAFT_1_16_4(754, "1.16.4", "1.16.5"),
-  MINECRAFT_1_17(755, "1.17");
+  MINECRAFT_1_17(755, "1.17"),
+  MINECRAFT_1_17_1(756, "1.17.1");
 
   private static final int SNAPSHOT_BIT = 30;
 
diff --git a/proxy/src/main/java/com/velocitypowered/proxy/Velocity.java b/proxy/src/main/java/com/velocitypowered/proxy/Velocity.java
index 2362a4df7..25b3a7c47 100644
--- a/proxy/src/main/java/com/velocitypowered/proxy/Velocity.java
+++ b/proxy/src/main/java/com/velocitypowered/proxy/Velocity.java
@@ -35,17 +35,6 @@ public class Velocity {
     // How inconvenient. Force AWT to work with its head chopped off.
     System.setProperty("java.awt.headless", "true");
 
-    // By default, Netty allocates 16MiB arenas for the PooledByteBufAllocator. This is too much
-    // memory for Minecraft, which imposes a maximum packet size of 2MiB! We'll use 4MiB as a more
-    // sane default.
-    //
-    // Note: io.netty.allocator.pageSize << io.netty.allocator.maxOrder is the formula used to
-    // compute the chunk size. We lower maxOrder from its default of 11 to 9. (We also use a null
-    // check, so that the user is free to choose another setting if need be.)
-    if (System.getProperty("io.netty.allocator.maxOrder") == null) {
-      System.setProperty("io.netty.allocator.maxOrder", "9");
-    }
-
     // If Velocity's natives are being extracted to a different temporary directory, make sure the
     // Netty natives are extracted there as well
     if (System.getProperty("velocity.natives-tmpdir") != null) {
diff --git a/proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftCompressDecoder.java b/proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftCompressDecoder.java
index ccadf9d72..82fb4c153 100644
--- a/proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftCompressDecoder.java
+++ b/proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftCompressDecoder.java
@@ -30,7 +30,7 @@ import java.util.List;
 
 public class MinecraftCompressDecoder extends MessageToMessageDecoder<ByteBuf> {
 
-  private static final int VANILLA_MAXIMUM_UNCOMPRESSED_SIZE = 2 * 1024 * 1024; // 2MiB
+  private static final int VANILLA_MAXIMUM_UNCOMPRESSED_SIZE = 8 * 1024 * 1024; // 8MiB
   private static final int HARD_MAXIMUM_UNCOMPRESSED_SIZE = 16 * 1024 * 1024; // 16MiB
 
   private static final int UNCOMPRESSED_CAP =
diff --git a/proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftCompressorAndLengthEncoder.java b/proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftCompressorAndLengthEncoder.java
index 28d005161..67ec9e1e2 100644
--- a/proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftCompressorAndLengthEncoder.java
+++ b/proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftCompressorAndLengthEncoder.java
@@ -29,9 +29,6 @@ import java.util.zip.DataFormatException;
 
 public class MinecraftCompressorAndLengthEncoder extends MessageToByteEncoder<ByteBuf> {
 
-  private static final boolean MUST_USE_SAFE_AND_SLOW_COMPRESSION_HANDLING =
-      Boolean.getBoolean("velocity.increased-compression-cap");
-
   private int threshold;
   private final VelocityCompressor compressor;
 
@@ -49,15 +46,11 @@ public class MinecraftCompressorAndLengthEncoder extends MessageToByteEncoder<By
       ProtocolUtils.writeVarInt(out, 0);
       out.writeBytes(msg);
     } else {
-      if (MUST_USE_SAFE_AND_SLOW_COMPRESSION_HANDLING) {
-        handleCompressedSafe(ctx, msg, out);
-      } else {
-        handleCompressedFast(ctx, msg, out);
-      }
+      handleCompressed(ctx, msg, out);
     }
   }
 
-  private void handleCompressedFast(ChannelHandlerContext ctx, ByteBuf msg, ByteBuf out)
+  private void handleCompressed(ChannelHandlerContext ctx, ByteBuf msg, ByteBuf out)
       throws DataFormatException {
     int uncompressed = msg.readableBytes();
 
@@ -73,9 +66,7 @@ public class MinecraftCompressorAndLengthEncoder extends MessageToByteEncoder<By
     }
     int compressedLength = out.writerIndex() - startCompressed;
     if (compressedLength >= 1 << 21) {
-      throw new DataFormatException("The server sent a very large (over 2MiB compressed) packet. "
-          + "Please restart Velocity with the JVM flag -Dvelocity.increased-compression-cap=true "
-          + "to fix this issue.");
+      throw new DataFormatException("The server sent a very large (over 2MiB compressed) packet.");
     }
 
     int writerIndex = out.writerIndex();
@@ -85,26 +76,6 @@ public class MinecraftCompressorAndLengthEncoder extends MessageToByteEncoder<By
     out.writerIndex(writerIndex);
   }
 
-  private void handleCompressedSafe(ChannelHandlerContext ctx, ByteBuf msg, ByteBuf out)
-      throws DataFormatException {
-    int uncompressed = msg.readableBytes();
-    ByteBuf tmpBuf = MoreByteBufUtils.preferredBuffer(ctx.alloc(), compressor, uncompressed - 1);
-    try {
-      ProtocolUtils.writeVarInt(tmpBuf, uncompressed);
-      ByteBuf compatibleIn = MoreByteBufUtils.ensureCompatible(ctx.alloc(), compressor, msg);
-      try {
-        compressor.deflate(compatibleIn, tmpBuf);
-      } finally {
-        compatibleIn.release();
-      }
-
-      ProtocolUtils.writeVarInt(out, tmpBuf.readableBytes());
-      out.writeBytes(tmpBuf);
-    } finally {
-      tmpBuf.release();
-    }
-  }
-
   @Override
   protected ByteBuf allocateBuffer(ChannelHandlerContext ctx, ByteBuf msg, boolean preferDirect)
       throws Exception {