Merge branch 'GrimAnticheat:2.0' into 2.0

Author: Anthony01M

README.md

@@ -1,6 +1,6 @@
 # GrimAC
 
-This project is considered feature complete for the 2.0 (open-source) branch of this project. If you would like a bugfix or enhancement and cannot sponsor the work, pull requests are welcome. You can join the [discord](https://discord.gg/SEywtQMt29) for jar releases & changelogs.
+This project is considered feature complete for the 2.0 (open-source) branch of this project. If you would like a bugfix or enhancement and cannot sponsor the work, pull requests are welcome. You can join the [discord](https://discord.com/invite/kqQAhTmkUF) for jar releases & changelogs.
 
 GrimAC is an open source Minecraft anticheat designed for 1.20 and supports 1.8-1.20. It is free while in beta. It will eventually become paid and/or will include offering additional subscription based paid checks. Geyser players are fully exempt.
 

build.gradle.kts

@@ -10,7 +10,7 @@ plugins {
 
 
 group = "ac.grim.grimac"
-version = "2.3.63"
+version = "2.3.64"
 description = "Libre simulation anticheat designed for 1.20 with 1.8-1.20 support, powered by PacketEvents 2.0."
 java.sourceCompatibility = JavaVersion.VERSION_1_8
 java.targetCompatibility = JavaVersion.VERSION_1_8
@@ -41,7 +41,7 @@ dependencies {
 
     implementation("org.jetbrains:annotations:24.1.0")
     compileOnly("org.geysermc.floodgate:api:2.0-SNAPSHOT")
-    compileOnly("org.spigotmc:spigot-api:1.20.6-R0.1-SNAPSHOT")
+    compileOnly("org.spigotmc:spigot-api:1.18.2-R0.1-SNAPSHOT")
     compileOnly("com.viaversion:viaversion-api:4.9.4-SNAPSHOT")
     //
     compileOnly("io.netty:netty-all:4.1.85.Final")

src/main/java/ac/grim/grimac/checks/impl/badpackets/BadPacketsZ.java

@@ -0,0 +1,102 @@
+package ac.grim.grimac.checks.impl.badpackets;
+
+import ac.grim.grimac.checks.Check;
+import ac.grim.grimac.checks.CheckData;
+import ac.grim.grimac.checks.type.PacketCheck;
+import ac.grim.grimac.player.GrimPlayer;
+import com.github.retrooper.packetevents.event.PacketReceiveEvent;
+import com.github.retrooper.packetevents.protocol.player.ClientVersion;
+import com.github.retrooper.packetevents.protocol.player.DiggingAction;
+import com.github.retrooper.packetevents.util.Vector3i;
+import com.github.retrooper.packetevents.wrapper.play.client.WrapperPlayClientPlayerDigging;
+
+import static ac.grim.grimac.events.packets.patch.ResyncWorldUtil.resyncPosition;
+import static ac.grim.grimac.utils.nmsutil.BlockBreakSpeed.getBlockDamage;
+
+@CheckData(name = "BadPacketsZ", experimental = true)
+public class BadPacketsZ extends Check implements PacketCheck {
+    public BadPacketsZ(final GrimPlayer player) {
+        super(player);
+    }
+
+    private boolean exemptNextFinish = false;
+    private Vector3i lastBlock, lastLastBlock = null;
+    private final int exemptedY = player.getClientVersion().isNewerThanOrEquals(ClientVersion.V_1_8) ? 4095 : 255;
+
+    // The client sometimes sends a wierd cancel packet
+    private boolean shouldExempt(final Vector3i pos) {
+        // lastLastBlock is always null when this happens, and lastBlock isn't
+        if (lastLastBlock != null || lastBlock == null)
+            return false;
+
+        // on pre 1.14.4 clients, the YPos of this packet is always the same
+        if (player.getClientVersion().isOlderThan(ClientVersion.V_1_14_4) && pos.y != exemptedY)
+            return false;
+
+        // the client only sends this packet if the last block was an instant break
+        if (getBlockDamage(player, lastBlock) < 1)
+            return false;
+
+        // and if this block is not an instant break
+        return player.getClientVersion().isOlderThan(ClientVersion.V_1_14_4) || getBlockDamage(player, pos) < 1;
+    }
+
+    private String formatted(Vector3i vec) {
+        return vec == null ? "null" : vec.x + ", " + vec.y + ", " + vec.z;
+    }
+
+    public void handle(PacketReceiveEvent event, WrapperPlayClientPlayerDigging dig) {
+        if (dig.getAction() == DiggingAction.START_DIGGING) {
+            lastLastBlock = lastBlock;
+            lastBlock = dig.getBlockPosition();
+
+            exemptNextFinish = player.getClientVersion().isNewerThanOrEquals(ClientVersion.V_1_14_4) && getBlockDamage(player, lastBlock) >= 1;
+            return;
+        }
+
+        if (dig.getAction() == DiggingAction.CANCELLED_DIGGING) {
+            if (shouldExempt(dig.getBlockPosition())) {
+                lastLastBlock = null;
+                lastBlock = null;
+                return;
+            }
+
+            exemptNextFinish = false;
+
+            if ((lastBlock == null || !lastBlock.equals(dig.getBlockPosition())) && (lastLastBlock == null || !lastLastBlock.equals(dig.getBlockPosition()))) {
+                if (flagAndAlert("action=CANCELLED_DIGGING, last=" + formatted(lastBlock) + "/" + formatted(lastLastBlock) + ", pos=" + formatted(dig.getBlockPosition()))) {
+                    if (shouldModifyPackets()) {
+                        event.setCancelled(true);
+                        player.onPacketCancel();
+                    }
+                }
+            }
+
+            lastLastBlock = null;
+            lastBlock = null;
+        }
+
+        if (dig.getAction() == DiggingAction.FINISHED_DIGGING) {
+            if (exemptNextFinish) {
+                exemptNextFinish = false;
+                return;
+            }
+
+            if ((lastBlock == null || !lastBlock.equals(dig.getBlockPosition())) && (lastLastBlock == null || !lastLastBlock.equals(dig.getBlockPosition()))) {
+                if (flagAndAlert("action=FINISHED_DIGGING, last=" + formatted(lastBlock) + "/" + formatted(lastLastBlock) + ", pos=" + formatted(dig.getBlockPosition()))) {
+                    if (shouldModifyPackets()) {
+                        event.setCancelled(true);
+                        player.onPacketCancel();
+                        resyncPosition(player, dig.getBlockPosition());
+                    }
+                }
+            }
+
+            // 1.14.4+ clients don't send another start break in protected regions
+            if (player.getClientVersion().isOlderThan(ClientVersion.V_1_14_4)) {
+                lastLastBlock = null;
+                lastBlock = null;
+            }
+        }
+    }
+}

src/main/java/ac/grim/grimac/commands/GrimLog.java

@@ -30,7 +30,7 @@ public void onLog(CommandSender sender, int flagId) {
         } else {
             String uploading = GrimAPI.INSTANCE.getConfigManager().getConfig().getStringElse("upload-log-start", "%prefix% &fUploading log... please wait");
             String success = GrimAPI.INSTANCE.getConfigManager().getConfig().getStringElse("upload-log", "%prefix% &fUploaded debug to: %url%");
-            String failure = GrimAPI.INSTANCE.getConfigManager().getConfig().getStringElse("upload-log-upload-failure", "%prefix% &cSomething went wrong while uploading this log, see console for more info");
+            String failure = GrimAPI.INSTANCE.getConfigManager().getConfig().getStringElse("upload-log-upload-failure", "%prefix% &cSomething went wrong while uploading this log, see console for more information.");
 
             sender.sendMessage(MessageUtil.format(uploading));
 

src/main/java/ac/grim/grimac/commands/GrimProfile.java

@@ -29,7 +29,7 @@ public void onConsoleDebug(CommandSender sender, OnlinePlayer target) {
 
         // Short circuit due to minimum java requirements for MultiLib
         if (PacketEvents.getAPI().getServerManager().getVersion().isNewerThanOrEquals(ServerVersion.V_1_18) && MultiLibUtil.isExternalPlayer(target.getPlayer())) {
-            String alertString = GrimAPI.INSTANCE.getConfigManager().getConfig().getStringElse("player-not-this-server", "%prefix% &cPlayer isn't on this server!");
+            String alertString = GrimAPI.INSTANCE.getConfigManager().getConfig().getStringElse("player-not-this-server", "%prefix% &cThis player isn't on this server!");
             sender.sendMessage(MessageUtil.format(alertString));
             return;
         }

src/main/java/ac/grim/grimac/commands/GrimSpectate.java

@@ -33,7 +33,7 @@ public void onSpectate(CommandSender sender, @Optional OnlinePlayer target) {
         }
 
         if (target == null || (PacketEvents.getAPI().getServerManager().getVersion().isNewerThanOrEquals(ServerVersion.V_1_18) && MultiLibUtil.isExternalPlayer(target.getPlayer()))) {
-            String message = GrimAPI.INSTANCE.getConfigManager().getConfig().getStringElse("player-not-this-server", "%prefix% &cPlayer isn't on this server!");
+            String message = GrimAPI.INSTANCE.getConfigManager().getConfig().getStringElse("player-not-this-server", "%prefix% &cThis player isn't on this server!");
             sender.sendMessage(MessageUtil.format(message));
             return;
         }

src/main/java/ac/grim/grimac/commands/GrimStopSpectating.java

@@ -23,7 +23,7 @@ public void onStopSpectate(CommandSender sender, String[] args) {
             boolean teleportBack = string == null || !string.equalsIgnoreCase("here");
             GrimAPI.INSTANCE.getSpectateManager().disable(player, teleportBack);
         } else {
-            String message = GrimAPI.INSTANCE.getConfigManager().getConfig().getStringElse("cannot-spectate-return", "%prefix% &cYou can only do this after spectating a player");
+            String message = GrimAPI.INSTANCE.getConfigManager().getConfig().getStringElse("cannot-spectate-return", "%prefix% &cYou can only do this after spectating a player.");
             sender.sendMessage(MessageUtil.format(message));
         }
     }

src/main/java/ac/grim/grimac/events/packets/CheckManagerListener.java

@@ -2,6 +2,7 @@
 
 import ac.grim.grimac.GrimAPI;
 import ac.grim.grimac.checks.impl.badpackets.BadPacketsX;
+import ac.grim.grimac.checks.impl.badpackets.BadPacketsZ;
 import ac.grim.grimac.events.packets.patch.ResyncWorldUtil;
 import ac.grim.grimac.player.GrimPlayer;
 import ac.grim.grimac.utils.anticheat.update.*;
@@ -321,7 +322,9 @@ private static void handleBlockPlaceOrUseItem(PacketWrapper packet, GrimPlayer p
     }
 
     private boolean isMojangStupid(GrimPlayer player, WrapperPlayClientPlayerFlying flying) {
-        double threshold = player.getMovementThreshold();
+        final Location location = flying.getLocation();
+        final double threshold = player.getMovementThreshold();
+
         // Don't check duplicate 1.17 packets (Why would you do this mojang?)
         // Don't check rotation since it changes between these packets, with the second being irrelevant.
         //
@@ -333,21 +336,34 @@ private boolean isMojangStupid(GrimPlayer player, WrapperPlayClientPlayerFlying
                         // Mojang added this stupid mechanic in 1.17
                         && (player.getClientVersion().isNewerThanOrEquals(ClientVersion.V_1_17) &&
                         // Due to 0.03, we can't check exact position, only within 0.03
-                        player.filterMojangStupidityOnMojangStupidity.distanceSquared(flying.getLocation().getPosition()) < threshold * threshold))
+                        player.filterMojangStupidityOnMojangStupidity.distanceSquared(location.getPosition()) < threshold * threshold))
                         // If the player was in a vehicle, has position and look, and wasn't a teleport, then it was this stupid packet
                         || player.compensatedEntities.getSelf().inVehicle())) {
+
+            // Mark that we want this packet to be cancelled from reaching the server
+            // Additionally, only yaw/pitch matters: https://github.com/GrimAnticheat/Grim/issues/1275#issuecomment-1872444018
+            // 1.9+ isn't impacted by this packet as much.
+            if (PacketEvents.getAPI().getServerManager().getVersion().isOlderThanOrEquals(ServerVersion.V_1_9)) {
+                if (GrimAPI.INSTANCE.getConfigManager().getConfig().getBooleanElse("cancel-duplicate-packet", true)) {
+                    player.packetStateData.cancelDuplicatePacket = true;
+                }
+            } else {
+                // Override location to force it to use the last real position of the player. Prevents position-related bypasses like nofall.
+                flying.setLocation(new Location(player.filterMojangStupidityOnMojangStupidity.getX(), player.filterMojangStupidityOnMojangStupidity.getY(), player.filterMojangStupidityOnMojangStupidity.getZ(), location.getYaw(), location.getPitch()));
+            }
+
             player.packetStateData.lastPacketWasOnePointSeventeenDuplicate = true;
 
-            if (player.xRot != flying.getLocation().getYaw() || player.yRot != flying.getLocation().getPitch()) {
+            if (player.xRot != location.getYaw() || player.yRot != location.getPitch()) {
                 player.lastXRot = player.xRot;
                 player.lastYRot = player.yRot;
             }
 
             // Take the pitch and yaw, just in case we were wrong about this being a stupidity packet
-            player.xRot = flying.getLocation().getYaw();
-            player.yRot = flying.getLocation().getPitch();
+            player.xRot = location.getYaw();
+            player.yRot = location.getPitch();
 
-            player.packetStateData.lastClaimedPosition = flying.getLocation().getPosition();
+            player.packetStateData.lastClaimedPosition = location.getPosition();
             return true;
         }
         return false;
@@ -399,6 +415,7 @@ public void onPacketReceive(PacketReceiveEvent event) {
 
         // The player flagged crasher or timer checks, therefore we must protect predictions against these attacks
         if (event.isCancelled() && (WrapperPlayClientPlayerFlying.isFlying(event.getPacketType()) || event.getPacketType() == PacketType.Play.Client.VEHICLE_MOVE)) {
+            player.packetStateData.cancelDuplicatePacket = false;
             return;
         }
 
@@ -435,6 +452,7 @@ public void onPacketReceive(PacketReceiveEvent event) {
             WrappedBlockState block = player.compensatedWorld.getWrappedBlockStateAt(dig.getBlockPosition());
 
             player.checkManager.getPacketCheck(BadPacketsX.class).handle(event, dig, block.getType());
+            player.checkManager.getPacketCheck(BadPacketsZ.class).handle(event, dig);
 
             if (dig.getAction() == DiggingAction.FINISHED_DIGGING) {
                 // Not unbreakable
@@ -546,6 +564,11 @@ public void onPacketReceive(PacketReceiveEvent event) {
         // Such as the NoFall check setting the player to not be on the ground
         player.checkManager.onPacketReceive(event);
 
+        if (player.packetStateData.cancelDuplicatePacket) {
+            event.setCancelled(true);
+            player.packetStateData.cancelDuplicatePacket = false;
+        }
+
         // Finally, remove the packet state variables on this packet
         player.packetStateData.lastPacketWasOnePointSeventeenDuplicate = false;
         player.packetStateData.lastPacketWasTeleport = false;

src/main/java/ac/grim/grimac/events/packets/PacketPlayerRespawn.java

@@ -24,12 +24,39 @@
 import java.util.List;
 import java.util.Objects;
 
+/**
+ * PlayerRespawnS2CPacket info (1.20.2+):
+ * If the world is different (check via registry key), world is recreated (all entities etc destroyed).
+ * <p>
+ * Client player is ALWAYS recreated
+ * <p>
+ * If the packet has the `KEEP_TRACKED_DATA` flag:
+ * Sneaking and Sprinting fields are kept on the new client player.
+ * <p>
+ * If the packet has the `KEEP_ATTRIBUTES` flag:
+ * Attributes are kept.
+ * <p>
+ * New client player is initialised:
+ * Pose is set to standing.
+ * Velocity is set to zero.
+ * Pitch is set to 0.
+ * Yaw is set to -180.
+ */
+// TODO update for 1.20.2-
 public class PacketPlayerRespawn extends PacketListenerAbstract {
 
     public PacketPlayerRespawn() {
         super(PacketListenerPriority.HIGH);
     }
 
+    private static final byte KEEP_ATTRIBUTES = 1;
+    private static final byte KEEP_TRACKED_DATA = 2;
+    private static final byte KEEP_ALL = 3;
+
+    private boolean hasFlag(WrapperPlayServerRespawn respawn, byte flag) {
+        return (respawn.getKeptData() & flag) != 0;
+    }
+
     @Override
     public void onPacketSend(PacketSendEvent event) {
         if (event.getPacketType() == PacketType.Play.Server.UPDATE_HEALTH) {
@@ -101,11 +128,17 @@ public void onPacketSend(PacketSendEvent event) {
             player.latencyUtils.addRealTimeTask(player.lastTransactionSent.get() + 1, () -> {
                 player.isSneaking = false;
                 player.lastOnGround = false;
+                player.onGround = false;
                 player.isInBed = false;
                 player.packetStateData.packetPlayerOnGround = false; // If somewhere else pulls last ground to fix other issues
                 player.packetStateData.lastClaimedPosition = new Vector3d();
                 player.filterMojangStupidityOnMojangStupidity = new Vector3d();
-                player.lastSprintingForSpeed = false; // This is reverted even on 1.18 clients
+
+                if (player.getClientVersion().isNewerThanOrEquals(ClientVersion.V_1_19_4)) {
+                    player.isSprinting = !this.hasFlag(respawn, KEEP_TRACKED_DATA);
+                } else {
+                    player.lastSprintingForSpeed = false;
+                }
 
                 player.checkManager.getPacketCheck(BadPacketsE.class).handleRespawn(); // Reminder ticks reset
 
@@ -141,6 +174,20 @@ public void onPacketSend(PacketSendEvent event) {
                 if (PacketEvents.getAPI().getServerManager().getVersion().isNewerThanOrEquals(ServerVersion.V_1_17)) {
                     player.compensatedWorld.setDimension(respawn.getDimension(), event.getUser());
                 }
+
+                // TODO this needs to be done for other client versions as well. And there should probably be some attribute holder that we can just call reset() on.
+                if (player.getClientVersion().isNewerThanOrEquals(ClientVersion.V_1_20_5) && !this.hasFlag(respawn, KEEP_ATTRIBUTES)) {
+                    // Reset attributes if not kept
+                    final PacketEntitySelf self = player.compensatedEntities.getSelf();
+                    self.gravityAttribute = 0.08d;
+                    self.stepHeight = 0.6f;
+                    self.scale = 1.0f;
+                    self.setJumpStrength(0.42f);
+                    self.setBreakSpeedMultiplier(1.0f);
+                    self.setBlockInteractRange(4.5);
+                    self.setEntityInteractRange(3.0);
+                    player.compensatedEntities.hasSprintingAttributeEnabled = false;
+                }
             });
         }
     }

src/main/java/ac/grim/grimac/manager/CheckManager.java

@@ -92,6 +92,7 @@ public CheckManager(GrimPlayer player) {
                 .put(BadPacketsW.class, new BadPacketsW(player))
                 .put(BadPacketsX.class, new BadPacketsX(player))
                 .put(BadPacketsY.class, new BadPacketsY(player))
+                .put(BadPacketsZ.class, new BadPacketsZ(player))
                 .put(FastBreak.class, new FastBreak(player))
                 .put(TransactionOrder.class, new TransactionOrder(player))
                 .put(NoSlowB.class, new NoSlowB(player))