From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Spottedleaf Date: Fri, 30 Oct 2020 22:37:16 -0700 Subject: [PATCH] Add packet limiter config Example config: packet-limiter: kick-message: '&cSent too many packets' limits: all: interval: 7.0 max-packet-rate: 500.0 ServerboundPlaceRecipePacket: interval: 4.0 max-packet-rate: 5.0 action: DROP all section refers to all incoming packets, the action for all is hard coded to KICK. For specific limits, the section name is the class's name, and an action can be defined: DROP or KICK If interval or rate are less-than 0, the limit is ignored diff --git a/src/main/java/net/minecraft/network/Connection.java b/src/main/java/net/minecraft/network/Connection.java index 363829a3bce2803e234ff81ae4b0cba3072fd5f9..7f089f7451b956e4c8cb6581354beb5fc4e45318 100644 --- a/src/main/java/net/minecraft/network/Connection.java +++ b/src/main/java/net/minecraft/network/Connection.java @@ -135,6 +135,22 @@ public class Connection extends SimpleChannelInboundHandler> { } } // Paper end - allow controlled flushing + // Paper start - packet limiter + protected final Object PACKET_LIMIT_LOCK = new Object(); + protected final @Nullable io.papermc.paper.util.IntervalledCounter allPacketCounts = io.papermc.paper.configuration.GlobalConfiguration.get().packetLimiter.allPackets.isEnabled() ? new io.papermc.paper.util.IntervalledCounter( + (long)(io.papermc.paper.configuration.GlobalConfiguration.get().packetLimiter.allPackets.interval() * 1.0e9) + ) : null; + protected final java.util.Map>, io.papermc.paper.util.IntervalledCounter> packetSpecificLimits = new java.util.HashMap<>(); + + private boolean stopReadingPackets; + private void killForPacketSpam() { + this.sendPacket(new ClientboundDisconnectPacket(io.papermc.paper.adventure.PaperAdventure.asVanilla(io.papermc.paper.configuration.GlobalConfiguration.get().packetLimiter.kickMessage)), (future) -> { + this.disconnect(io.papermc.paper.adventure.PaperAdventure.asVanilla(io.papermc.paper.configuration.GlobalConfiguration.get().packetLimiter.kickMessage)); + }); + this.setReadOnly(); + this.stopReadingPackets = true; + } + // Paper end - packet limiter public Connection(PacketFlow side) { this.receiving = side; @@ -215,6 +231,45 @@ public class Connection extends SimpleChannelInboundHandler> { protected void channelRead0(ChannelHandlerContext channelhandlercontext, Packet packet) { if (this.channel.isOpen()) { + // Paper start - packet limiter + if (this.stopReadingPackets) { + return; + } + if (this.allPacketCounts != null || + io.papermc.paper.configuration.GlobalConfiguration.get().packetLimiter.overrides.containsKey(packet.getClass())) { + long time = System.nanoTime(); + synchronized (PACKET_LIMIT_LOCK) { + if (this.allPacketCounts != null) { + this.allPacketCounts.updateAndAdd(1, time); + if (this.allPacketCounts.getRate() >= io.papermc.paper.configuration.GlobalConfiguration.get().packetLimiter.allPackets.maxPacketRate()) { + this.killForPacketSpam(); + return; + } + } + + for (Class check = packet.getClass(); check != Object.class; check = check.getSuperclass()) { + io.papermc.paper.configuration.GlobalConfiguration.PacketLimiter.PacketLimit packetSpecificLimit = + io.papermc.paper.configuration.GlobalConfiguration.get().packetLimiter.overrides.get(check); + if (packetSpecificLimit == null || !packetSpecificLimit.isEnabled()) { + continue; + } + io.papermc.paper.util.IntervalledCounter counter = this.packetSpecificLimits.computeIfAbsent((Class)check, (clazz) -> { + return new io.papermc.paper.util.IntervalledCounter((long)(packetSpecificLimit.interval() * 1.0e9)); + }); + counter.updateAndAdd(1, time); + if (counter.getRate() >= packetSpecificLimit.maxPacketRate()) { + switch (packetSpecificLimit.action()) { + case DROP: + return; + case KICK: + this.killForPacketSpam(); + return; + } + } + } + } + } + // Paper end - packet limiter try { Connection.genericsFtw(packet, this.packetListener); } catch (RunningOnDifferentThreadException cancelledpackethandleexception) {