Check payload size

modmuss50 · Oct 29, 2023 · ee43962 · ee43962
1 parent 0596ed7
commit ee43962
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Showing 5 changed files with 36 additions and 6 deletions.
diff --git a/...rking-api-v1/src/main/java/net/fabricmc/fabric/impl/networking/payload/PayloadHelper.java b/...rking-api-v1/src/main/java/net/fabricmc/fabric/impl/networking/payload/PayloadHelper.java
@@ -25,7 +25,13 @@ public static void write(PacketByteBuf byteBuf, PacketByteBuf data) {
 		byteBuf.writeBytes(data.copy());
 	}
 
-	public static PacketByteBuf read(PacketByteBuf byteBuf) {
+	public static PacketByteBuf read(PacketByteBuf byteBuf, int maxSize) {
+		int size = byteBuf.readableBytes();
+
+		if (size < 0 || size > maxSize) {
+			throw new IllegalArgumentException("Payload may not be larger than %d bytes".formatted(maxSize));
+		}
+
 		PacketByteBuf newBuf = PacketByteBufs.create();
 		newBuf.writeBytes(byteBuf.copy());
 		byteBuf.skipBytes(byteBuf.readableBytes());

diff --git a/...pi-v1/src/main/java/net/fabricmc/fabric/mixin/networking/CustomPayloadC2SPacketMixin.java b/...pi-v1/src/main/java/net/fabricmc/fabric/mixin/networking/CustomPayloadC2SPacketMixin.java
@@ -16,7 +16,9 @@
 
 package net.fabricmc.fabric.mixin.networking;
 
+import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
@@ -31,12 +33,16 @@
 
 @Mixin(CustomPayloadC2SPacket.class)
 public class CustomPayloadC2SPacketMixin {
+	@Shadow
+	@Final
+	private static int MAX_PAYLOAD_SIZE;
+
 	@Inject(
 			method = "readPayload",
 			at = @At(value = "INVOKE", target = "Lnet/minecraft/network/packet/c2s/common/CustomPayloadC2SPacket;readUnknownPayload(Lnet/minecraft/util/Identifier;Lnet/minecraft/network/PacketByteBuf;)Lnet/minecraft/network/packet/UnknownCustomPayload;"),
 			cancellable = true
 	)
 	private static void readPayload(Identifier id, PacketByteBuf buf, CallbackInfoReturnable<CustomPayload> cir) {
-		cir.setReturnValue(new PacketByteBufPayload(id, PayloadHelper.read(buf)));
+		cir.setReturnValue(new PacketByteBufPayload(id, PayloadHelper.read(buf, MAX_PAYLOAD_SIZE)));
 	}
 }
diff --git a/...pi-v1/src/main/java/net/fabricmc/fabric/mixin/networking/CustomPayloadS2CPacketMixin.java b/...pi-v1/src/main/java/net/fabricmc/fabric/mixin/networking/CustomPayloadS2CPacketMixin.java
@@ -16,7 +16,9 @@
 
 package net.fabricmc.fabric.mixin.networking;
 
+import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
@@ -31,12 +33,16 @@
 
 @Mixin(CustomPayloadS2CPacket.class)
 public class CustomPayloadS2CPacketMixin {
+	@Shadow
+	@Final
+	private static int MAX_PAYLOAD_SIZE;
+
 	@Inject(
 			method = "readPayload",
 			at = @At(value = "INVOKE", target = "Lnet/minecraft/network/packet/s2c/common/CustomPayloadS2CPacket;readUnknownPayload(Lnet/minecraft/util/Identifier;Lnet/minecraft/network/PacketByteBuf;)Lnet/minecraft/network/packet/UnknownCustomPayload;"),
 			cancellable = true
 	)
 	private static void readPayload(Identifier id, PacketByteBuf buf, CallbackInfoReturnable<CustomPayload> cir) {
-		cir.setReturnValue(new PacketByteBufPayload(id, PayloadHelper.read(buf)));
+		cir.setReturnValue(new PacketByteBufPayload(id, PayloadHelper.read(buf, MAX_PAYLOAD_SIZE)));
 	}
 }
diff --git a/...1/src/main/java/net/fabricmc/fabric/mixin/networking/LoginQueryRequestS2CPacketMixin.java b/...1/src/main/java/net/fabricmc/fabric/mixin/networking/LoginQueryRequestS2CPacketMixin.java
@@ -16,7 +16,9 @@
 
 package net.fabricmc.fabric.mixin.networking;
 
+import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
@@ -31,8 +33,12 @@
 
 @Mixin(LoginQueryRequestS2CPacket.class)
 public class LoginQueryRequestS2CPacketMixin {
+	@Shadow
+	@Final
+	private static int MAX_PAYLOAD_SIZE;
+
 	@Inject(method = "readPayload", at = @At("HEAD"), cancellable = true)
 	private static void readPayload(Identifier id, PacketByteBuf buf, CallbackInfoReturnable<LoginQueryRequestPayload> cir) {
-		cir.setReturnValue(new PacketByteBufLoginQueryRequestPayload(id, PayloadHelper.read(buf)));
+		cir.setReturnValue(new PacketByteBufLoginQueryRequestPayload(id, PayloadHelper.read(buf, MAX_PAYLOAD_SIZE)));
 	}
 }
diff --git a/.../src/main/java/net/fabricmc/fabric/mixin/networking/LoginQueryResponseC2SPacketMixin.java b/.../src/main/java/net/fabricmc/fabric/mixin/networking/LoginQueryResponseC2SPacketMixin.java
@@ -16,20 +16,26 @@
 
 package net.fabricmc.fabric.mixin.networking;
 
+import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 
 import net.minecraft.network.PacketByteBuf;
-import net.minecraft.network.packet.c2s.login.LoginQueryResponsePayload;
 import net.minecraft.network.packet.c2s.login.LoginQueryResponseC2SPacket;
+import net.minecraft.network.packet.c2s.login.LoginQueryResponsePayload;
 
 import net.fabricmc.fabric.impl.networking.payload.PacketByteBufLoginQueryResponse;
 import net.fabricmc.fabric.impl.networking.payload.PayloadHelper;
 
 @Mixin(LoginQueryResponseC2SPacket.class)
 public class LoginQueryResponseC2SPacketMixin {
+	@Shadow
+	@Final
+	private static int MAX_PAYLOAD_SIZE;
+
 	@Inject(method = "readPayload", at = @At("HEAD"), cancellable = true)
 	private static void readResponse(int queryId, PacketByteBuf buf, CallbackInfoReturnable<LoginQueryResponsePayload> cir) {
 		boolean hasPayload = buf.readBoolean();
@@ -39,6 +45,6 @@ private static void readResponse(int queryId, PacketByteBuf buf, CallbackInfoRet
 			return;
 		}
 
-		cir.setReturnValue(new PacketByteBufLoginQueryResponse(PayloadHelper.read(buf)));
+		cir.setReturnValue(new PacketByteBufLoginQueryResponse(PayloadHelper.read(buf, MAX_PAYLOAD_SIZE)));
 	}
 }