aboutsummaryrefslogtreecommitdiffhomepage
path: root/patches/server/0958-Handle-Large-Packets-disconnecting-client.patch
blob: ea20a101a74d1464064d2b30d2e8c98730a97c27 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Tue, 27 Nov 2018 21:18:06 -0500
Subject: [PATCH] Handle Large Packets disconnecting client

If a players inventory is too big to send in a single packet,
split the inventory set into multiple packets instead.

diff --git a/src/main/java/net/minecraft/network/Connection.java b/src/main/java/net/minecraft/network/Connection.java
index a8dfe7a4b3d01bf75587be078f471d1ef1d7a667..ea16dfa718b526d6520d7fcfc21d28f972f1f2bf 100644
--- a/src/main/java/net/minecraft/network/Connection.java
+++ b/src/main/java/net/minecraft/network/Connection.java
@@ -176,6 +176,21 @@ public class Connection extends SimpleChannelInboundHandler<Packet<?>> {
     }
 
     public void exceptionCaught(ChannelHandlerContext channelhandlercontext, Throwable throwable) {
+        // Paper start - Handle large packets disconnecting client
+        if (throwable instanceof io.netty.handler.codec.EncoderException && throwable.getCause() instanceof PacketEncoder.PacketTooLargeException packetTooLargeException) {
+            final Packet<?> packet = packetTooLargeException.getPacket();
+            if (packet.packetTooLarge(this)) {
+                ProtocolSwapHandler.handleOutboundTerminalPacket(channelhandlercontext, packet);
+                return;
+            } else if (packet.isSkippable()) {
+                Connection.LOGGER.debug("Skipping packet due to errors", throwable.getCause());
+                ProtocolSwapHandler.handleOutboundTerminalPacket(channelhandlercontext, packet);
+                return;
+            } else {
+                throwable = throwable.getCause();
+            }
+        }
+        // Paper end - Handle large packets disconnecting client
         if (throwable instanceof SkipPacketException) {
             Connection.LOGGER.debug("Skipping packet due to errors", throwable.getCause());
         } else {
diff --git a/src/main/java/net/minecraft/network/PacketEncoder.java b/src/main/java/net/minecraft/network/PacketEncoder.java
index 046bfc212b640de174b300e7a05cc30bb3cac93e..af3ec112e142a2c91c46882dad6180b18f39eec2 100644
--- a/src/main/java/net/minecraft/network/PacketEncoder.java
+++ b/src/main/java/net/minecraft/network/PacketEncoder.java
@@ -40,7 +40,33 @@ public class PacketEncoder<T extends PacketListener> extends MessageToByteEncode
 
             throw var9;
         } finally {
+            // Paper start - Handle large packets disconnecting client
+            int packetLength = byteBuf.readableBytes();
+            if (packetLength > MAX_PACKET_SIZE || (packetLength > MAX_FINAL_PACKET_SIZE && packet.hasLargePacketFallback())) {
+                throw new PacketTooLargeException(packet, packetLength);
+            }
+            // Paper end - Handle large packets disconnecting client
             ProtocolSwapHandler.handleOutboundTerminalPacket(channelHandlerContext, packet);
         }
     }
+
+    // Paper start
+    // packet size is encoded into 3-byte varint
+    private static final int MAX_FINAL_PACKET_SIZE = (1 << 21) - 1;
+    // Vanilla Max size for the encoder (before compression)
+    private static final int MAX_PACKET_SIZE = 8388608;
+
+    public static class PacketTooLargeException extends RuntimeException {
+        private final Packet<?> packet;
+
+        PacketTooLargeException(Packet<?> packet, int packetLength) {
+            super("PacketTooLarge - " + packet.getClass().getSimpleName() + " is " + packetLength + ". Max is " + MAX_PACKET_SIZE);
+            this.packet = packet;
+        }
+
+        public Packet<?> getPacket() {
+            return this.packet;
+        }
+    }
+    // Paper end
 }
diff --git a/src/main/java/net/minecraft/network/protocol/Packet.java b/src/main/java/net/minecraft/network/protocol/Packet.java
index 4c776c591dd0a7b36945a6487fdfe86d1187b4af..82fc12ffbd1585b4a8d09a025914830af77b0f8d 100644
--- a/src/main/java/net/minecraft/network/protocol/Packet.java
+++ b/src/main/java/net/minecraft/network/protocol/Packet.java
@@ -11,6 +11,19 @@ public interface Packet<T extends PacketListener> {
 
     void handle(T listener);
 
+    // Paper start
+    default boolean hasLargePacketFallback() {
+        return false;
+    }
+
+    /**
+     * override {@link #hasLargePacketFallback()} to return true when overriding in subclasses
+     */
+    default boolean packetTooLarge(net.minecraft.network.Connection manager) {
+        return false;
+    }
+    // Paper end
+
     default boolean isSkippable() {
         return false;
     }
diff --git a/src/main/java/net/minecraft/network/protocol/game/ClientboundContainerSetContentPacket.java b/src/main/java/net/minecraft/network/protocol/game/ClientboundContainerSetContentPacket.java
index 7e555ece0555b3d2a983ab2c39c5e7ec23fc7e88..8cca2ac616a2c80268c96b9f95e33f834a0fc8fd 100644
--- a/src/main/java/net/minecraft/network/protocol/game/ClientboundContainerSetContentPacket.java
+++ b/src/main/java/net/minecraft/network/protocol/game/ClientboundContainerSetContentPacket.java
@@ -36,6 +36,21 @@ public class ClientboundContainerSetContentPacket implements Packet<ClientGamePa
         this.carriedItem = ItemStack.OPTIONAL_STREAM_CODEC.decode(buf);
     }
 
+    // Paper start - Handle large packets disconnecting client
+    @Override
+    public boolean hasLargePacketFallback() {
+        return true;
+    }
+
+    @Override
+    public boolean packetTooLarge(net.minecraft.network.Connection manager) {
+        for (int i = 0 ; i < this.items.size() ; i++) {
+            manager.send(new ClientboundContainerSetSlotPacket(this.containerId, this.stateId, i, this.items.get(i)));
+        }
+        return true;
+    }
+    // Paper end - Handle large packets disconnecting client
+
     private void write(RegistryFriendlyByteBuf buf) {
         buf.writeByte(this.containerId);
         buf.writeVarInt(this.stateId);
diff --git a/src/main/java/net/minecraft/network/protocol/game/ClientboundLevelChunkPacketData.java b/src/main/java/net/minecraft/network/protocol/game/ClientboundLevelChunkPacketData.java
index ec1cb034d840633240f2b379b09f7d2f1c8971a5..cf8fd671490863e126c059157e1ca234e6509d9f 100644
--- a/src/main/java/net/minecraft/network/protocol/game/ClientboundLevelChunkPacketData.java
+++ b/src/main/java/net/minecraft/network/protocol/game/ClientboundLevelChunkPacketData.java
@@ -52,7 +52,7 @@ public class ClientboundLevelChunkPacketData {
             throw new RuntimeException("Can't read heightmap in packet for [" + x + ", " + z + "]");
         } else {
             int i = buf.readVarInt();
-            if (i > 2097152) {
+            if (i > 2097152) { // Paper - diff on change - if this changes, update PacketEncoder
                 throw new RuntimeException("Chunk Packet trying to allocate too much memory on read.");
             } else {
                 this.buffer = new byte[i];