1 files changed, 151 insertions, 0 deletions
diff --git a/EssentialsAntiCheat/src/com/earth2me/essentials/anticheat/checks/moving/NoFallCheck.java b/EssentialsAntiCheat/src/com/earth2me/essentials/anticheat/checks/moving/NoFallCheck.java
new file mode 100644
index 000000000..6a531e3c2
--- /dev/null
+++ b/EssentialsAntiCheat/src/com/earth2me/essentials/anticheat/checks/moving/NoFallCheck.java
@@ -0,0 +1,151 @@
+package com.earth2me.essentials.anticheat.checks.moving;
+
+import com.earth2me.essentials.anticheat.NoCheat;
+import com.earth2me.essentials.anticheat.NoCheatPlayer;
+import com.earth2me.essentials.anticheat.actions.ParameterName;
+import com.earth2me.essentials.anticheat.data.Statistics.Id;
+import java.util.Locale;
+
+
+/**
+ * A check to see if people cheat by tricking the server to not deal them fall damage.
+ *
+ */
+public class NoFallCheck extends MovingCheck
+{
+	public NoFallCheck(NoCheat plugin)
+	{
+		super(plugin, "moving.nofall");
+	}
+
+	/**
+	 * Calculate if and how much the player "failed" this check.
+	 *
+	 */
+	public void check(NoCheatPlayer player, MovingData data, MovingConfig cc)
+	{
+
+		// If the player is serverside in creative mode, we have to stop here to
+		// avoid hurting him when he switches back to "normal" mode
+		if (player.isCreative())
+		{
+			data.fallDistance = 0F;
+			data.lastAddedFallDistance = 0F;
+			return;
+		}
+
+		// This check is pretty much always a step behind for technical reasons.
+		if (data.fromOnOrInGround)
+		{
+			// Start with zero fall distance
+			data.fallDistance = 0F;
+		}
+
+		if (cc.nofallaggressive && data.fromOnOrInGround && data.toOnOrInGround && data.from.y <= data.to.y && player.getPlayer().getFallDistance() > 3.0F)
+		{
+			data.fallDistance = player.getPlayer().getFallDistance();
+			data.nofallVL += data.fallDistance;
+			incrementStatistics(player, Id.MOV_NOFALL, data.fallDistance);
+
+			// Execute whatever actions are associated with this check and the
+			// violation level and find out if we should cancel the event
+			final boolean cancel = executeActions(player, cc.nofallActions, data.nofallVL);
+			if (cancel)
+			{
+				player.dealFallDamage();
+			}
+			data.fallDistance = 0F;
+		}
+
+		// If we increased fall height before for no good reason, reduce now by
+		// the same amount
+		if (player.getPlayer().getFallDistance() > data.lastAddedFallDistance)
+		{
+			player.getPlayer().setFallDistance(player.getPlayer().getFallDistance() - data.lastAddedFallDistance);
+		}
+
+		data.lastAddedFallDistance = 0;
+
+		// We want to know if the fallDistance recorded by the game is smaller
+		// than the fall distance recorded by the plugin
+		final float difference = data.fallDistance - player.getPlayer().getFallDistance();
+
+		if (difference > 1.0F && data.toOnOrInGround && data.fallDistance > 2.0F)
+		{
+			data.nofallVL += difference;
+			incrementStatistics(player, Id.MOV_NOFALL, difference);
+
+			// Execute whatever actions are associated with this check and the
+			// violation level and find out if we should cancel the event
+			final boolean cancel = executeActions(player, cc.nofallActions, data.nofallVL);
+
+			// If "cancelled", the fall damage gets dealt in a way that's
+			// visible to other plugins
+			if (cancel)
+			{
+				// Increase the fall distance a bit :)
+				final float totalDistance = data.fallDistance + difference * (cc.nofallMultiplier - 1.0F);
+
+				player.getPlayer().setFallDistance(totalDistance);
+			}
+
+			data.fallDistance = 0F;
+		}
+
+		// Increase the fall distance that is recorded by the plugin, AND set
+		// the fall distance of the player
+		// to whatever he would get with this move event. This modifies
+		// Minecrafts fall damage calculation
+		// slightly, but that's still better than ignoring players that try to
+		// use "teleports" or "stepdown"
+		// to avoid falldamage. It is only added for big height differences
+		// anyway, as to avoid to much deviation
+		// from the original Minecraft feeling.
+
+		final double oldY = data.from.y;
+		final double newY = data.to.y;
+
+		if (oldY > newY)
+		{
+			final float dist = (float)(oldY - newY);
+			data.fallDistance += dist;
+
+			if (dist > 1.0F)
+			{
+				data.lastAddedFallDistance = dist;
+				player.getPlayer().setFallDistance(player.getPlayer().getFallDistance() + dist);
+			}
+			else
+			{
+				data.lastAddedFallDistance = 0.0F;
+			}
+		}
+		else
+		{
+			data.lastAddedFallDistance = 0.0F;
+		}
+
+		// Reduce falldamage violation level
+		data.nofallVL *= 0.95D;
+
+		return;
+	}
+
+	@Override
+	public String getParameter(ParameterName wildcard, NoCheatPlayer player)
+	{
+
+		if (wildcard == ParameterName.VIOLATIONS)
+		{
+			return String.format(Locale.US, "%d", (int)getData(player).nofallVL);
+		}
+		else if (wildcard == ParameterName.FALLDISTANCE)
+		{
+			return String.format(Locale.US, "%.2f", getData(player).fallDistance);
+		}
+		else
+		{
+			return super.getParameter(wildcard, player);
+		}
+	}
+}