From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Cryptite Date: Wed, 6 Oct 2021 11:03:01 -0500 Subject: [PATCH] (Slice) Packet obfuscation and reduction Minecraft is overzealous about packet updates for Entities. In Loka's case, we want to reduce as many unnecessary packet updates as possible. This patch is likely to be updated over and over in terms of reducing packet sends. In summary, this patch creates the concept of a "foreignValue" of a packet's data. We treat packets in two ways: 1) The packet sent to the player itself (the normal way). This always has all of the values as usual. 2) The packet data as seen by any other (foreign) players. This patch adds the ability to set a "foreignValue" for an entity value so as to obfuscate data received by other players. The current packets modified/obfuscated are the following: # This reduces the amount of health packet updates as well which is great for players in combat. # Air level packets are sent PER-TICK, and as such a player with any change in air level will only spam themselves # with packets instead of every single player within tracking distance diff --git a/src/main/java/net/minecraft/network/syncher/SynchedEntityData.java b/src/main/java/net/minecraft/network/syncher/SynchedEntityData.java index 0f99733660f91280e4c6262cf75b3c9cae86f65a..ba9f8fe6fafc54bbdfb104de28af4b392feb4483 100644 --- a/src/main/java/net/minecraft/network/syncher/SynchedEntityData.java +++ b/src/main/java/net/minecraft/network/syncher/SynchedEntityData.java @@ -22,6 +22,7 @@ public class SynchedEntityData { private final SyncedDataHolder entity; private final SynchedEntityData.DataItem[] itemsById; private boolean isDirty; + private boolean isForeignDirty; // Slice SynchedEntityData(SyncedDataHolder trackedEntity, SynchedEntityData.DataItem[] entries) { this.entity = trackedEntity; @@ -63,6 +64,16 @@ public class SynchedEntityData { } public void set(EntityDataAccessor key, T value, boolean force) { + // Slice start + this.set(key, value, null, force); + } + + public void set(EntityDataAccessor key, T value, T foreignValue) { + this.set(key, value, foreignValue, false); + } + + public void set(EntityDataAccessor key, T value, T foreignValue, boolean force) { + // Slice end SynchedEntityData.DataItem datawatcher_item = this.getItem(key); if (force || ObjectUtils.notEqual(value, datawatcher_item.getValue())) { @@ -72,6 +83,12 @@ public class SynchedEntityData { this.isDirty = true; } + // Slice start + if (foreignValue != null && ObjectUtils.notEqual(foreignValue, datawatcher_item.getForeignValue())) { + datawatcher_item.setForeignValue(foreignValue); + this.isForeignDirty = true; + } + // Slice end } // CraftBukkit start - add method from above @@ -81,6 +98,12 @@ public class SynchedEntityData { } // CraftBukkit end + // Slice start + public boolean isForeignDirty() { + return this.isForeignDirty; + } + // Slice end + public boolean isDirty() { return this.isDirty; } @@ -108,6 +131,29 @@ public class SynchedEntityData { } } + // Slice start + @Nullable + public List> packForeignDirty(List> unpackedData) { + List> list = null; + + for (DataValue dataItem : unpackedData) { + DataItem item = this.itemsById[dataItem.id()]; + if (item.isDirty(true)) { + item.setForeignDirty(false); + + if (list == null) { + list = new ArrayList<>(); + } + + list.add(item.copy(true)); + } + } + + this.isForeignDirty = false; + return list; + } + // Slice end + @Nullable public List> getNonDefaultValues() { List> list = null; @@ -171,11 +217,14 @@ public class SynchedEntityData { T value; private final T initialValue; private boolean dirty; + @Nullable T foreignValue = null; // Slice + private boolean foreignDirty; // Slice public DataItem(EntityDataAccessor data, T value) { this.accessor = data; this.initialValue = value; this.value = value; + this.foreignDirty = true; // Slice } public EntityDataAccessor getAccessor() { @@ -202,6 +251,35 @@ public class SynchedEntityData { return this.initialValue.equals(this.value); } + // Slice start + public void setForeignValue(T foreignValue) { + this.foreignValue = foreignValue; + this.foreignDirty = true; + } + + public @Nullable T getForeignValue() { + return this.foreignValue; + } + + public boolean isDirty(boolean foreign) { + if (foreign) { + //There must be a foreign value in order for this to be dirty, otherwise we consider this a normal + //value and check the normal dirty flag. + return this.foreignValue == null || this.foreignDirty; + } + + return this.dirty; + } + + public void setForeignDirty(boolean dirty) { + this.foreignDirty = dirty; + } + + public SynchedEntityData.DataValue copy(boolean foreign) { + return SynchedEntityData.DataValue.create(this.accessor, this.accessor.serializer().copy((foreign && this.foreignValue != null ? this.foreignValue : this.value))); + } + // Slice end + public SynchedEntityData.DataValue value() { return SynchedEntityData.DataValue.create(this.accessor, this.value); } diff --git a/src/main/java/net/minecraft/server/level/ServerEntity.java b/src/main/java/net/minecraft/server/level/ServerEntity.java index a2279262c93408c11f5d2290b48fd794975e8cfe..09975c9be245207281b616f77c768aa048b0c140 100644 --- a/src/main/java/net/minecraft/server/level/ServerEntity.java +++ b/src/main/java/net/minecraft/server/level/ServerEntity.java @@ -148,7 +148,7 @@ public class ServerEntity { } } - if (this.forceStateResync || this.tickCount % this.updateInterval == 0 || this.entity.hasImpulse || this.entity.getEntityData().isDirty()) { // Paper - fix desync when a player is added to the tracker + if (this.forceStateResync || this.tickCount % this.updateInterval == 0 || this.entity.hasImpulse || this.entity.getEntityData().isForeignDirty()) { // Slice// Paper - fix desync when a player is added to the tracker int i; int j; @@ -390,7 +390,15 @@ public class ServerEntity { if (list != null) { this.trackedDataValues = datawatcher.getNonDefaultValues(); - this.broadcastAndSend(new ClientboundSetEntityDataPacket(this.entity.getId(), list)); + // Slice start + if (!(this.entity instanceof ServerPlayer)) { + list = datawatcher.packForeignDirty(list); + } + + if (list != null) { + this.broadcastAndSend(new ClientboundSetEntityDataPacket(this.entity.getId(), list)); + } + // Slice end } if (this.entity instanceof LivingEntity) { diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java index 88d01e59869f8e6c528fb3ae1485cd86a23cb383..6f330f99a80f291bce638b0769e5ed00c283ac78 100644 --- a/src/main/java/net/minecraft/world/entity/Entity.java +++ b/src/main/java/net/minecraft/world/entity/Entity.java @@ -3470,7 +3470,7 @@ public abstract class Entity implements SyncedDataHolder, Nameable, EntityAccess this.entityData.markDirty(Entity.DATA_AIR_SUPPLY_ID); return; } - this.entityData.set(Entity.DATA_AIR_SUPPLY_ID, event.getAmount()); + this.entityData.set(Entity.DATA_AIR_SUPPLY_ID, event.getAmount(), getMaxAirSupply()); // Slice // CraftBukkit end } diff --git a/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java b/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java index b6a4753252b748c06a62b7faa6b05c1fb904d62e..86e12495ce807ba06210535350caa7db5e15d139 100644 --- a/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java +++ b/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java @@ -111,7 +111,7 @@ public class FallingBlockEntity extends Entity { } public void setStartPos(BlockPos pos) { - this.entityData.set(FallingBlockEntity.DATA_START_POS, pos); + this.entityData.set(FallingBlockEntity.DATA_START_POS, pos, BlockPos.ZERO); // Slice } public BlockPos getStartPos() { diff --git a/src/main/java/net/minecraft/world/entity/item/PrimedTnt.java b/src/main/java/net/minecraft/world/entity/item/PrimedTnt.java index 09f09a8fbf0eee62295001ce5b7ed5329445d2b0..16340c2f8a948136c9fe0b2314c9ec7cbee74937 100644 --- a/src/main/java/net/minecraft/world/entity/item/PrimedTnt.java +++ b/src/main/java/net/minecraft/world/entity/item/PrimedTnt.java @@ -182,7 +182,7 @@ public class PrimedTnt extends Entity implements TraceableEntity { } public void setFuse(int fuse) { - this.entityData.set(PrimedTnt.DATA_FUSE_ID, fuse); + this.entityData.set(PrimedTnt.DATA_FUSE_ID, fuse, (fuse / 10) * 10); // Slice } public int getFuse() { diff --git a/src/main/java/net/minecraft/world/entity/player/Player.java b/src/main/java/net/minecraft/world/entity/player/Player.java index 686374e89e41b0917791264f3281f7384835bca8..74130ccef989757b81507f084cc30a0e593ecaf3 100644 --- a/src/main/java/net/minecraft/world/entity/player/Player.java +++ b/src/main/java/net/minecraft/world/entity/player/Player.java @@ -645,7 +645,7 @@ public abstract class Player extends LivingEntity { public void increaseScore(int score) { int j = this.getScore(); - this.entityData.set(Player.DATA_SCORE_ID, j + score); + this.entityData.set(Player.DATA_SCORE_ID, j + score, 0); // Slice } public void startAutoSpinAttack(int riptideTicks) {