Paper/CraftBukkit-Patches/0019-Orebfuscator.patch

From 90de56da643bde4b842cc958a4b449634bb9ba8c Mon Sep 17 00:00:00 2001
From: md_5 <md_5@live.com.au>
Date: Thu, 16 May 2013 18:51:05 +1000
Subject: [PATCH] Orebfuscator


diff --git a/src/main/java/net/minecraft/server/EntityFallingBlock.java b/src/main/java/net/minecraft/server/EntityFallingBlock.java
index 17d837d..c7cd0ca 100644
--- a/src/main/java/net/minecraft/server/EntityFallingBlock.java
+++ b/src/main/java/net/minecraft/server/EntityFallingBlock.java
@@ -94,6 +94,7 @@ public class EntityFallingBlock extends Entity {
                     }
 
                     this.world.setAir(i, j, k);
+                    world.spigotConfig.antiXrayInstance.updateNearbyBlocks(world, i, j, k); // Spigot
                 }
 
                 if (this.onGround) {
diff --git a/src/main/java/net/minecraft/server/Explosion.java b/src/main/java/net/minecraft/server/Explosion.java
index ef220c1..2063769 100644
--- a/src/main/java/net/minecraft/server/Explosion.java
+++ b/src/main/java/net/minecraft/server/Explosion.java
@@ -240,6 +240,7 @@ public class Explosion {
                 j = chunkposition.y;
                 k = chunkposition.z;
                 l = this.world.getTypeId(i, j, k);
+                world.spigotConfig.antiXrayInstance.updateNearbyBlocks(world, i, j, k); // Spigot
                 if (flag) {
                     double d0 = (double) ((float) i + this.world.random.nextFloat());
                     double d1 = (double) ((float) j + this.world.random.nextFloat());
diff --git a/src/main/java/net/minecraft/server/Packet51MapChunk.java b/src/main/java/net/minecraft/server/Packet51MapChunk.java
index d11c0ea..efe102e 100644
--- a/src/main/java/net/minecraft/server/Packet51MapChunk.java
+++ b/src/main/java/net/minecraft/server/Packet51MapChunk.java
@@ -46,6 +46,7 @@ public class Packet51MapChunk extends Packet {
 
         this.d = chunkmap.c;
         this.c = chunkmap.b;
+        chunk.world.spigotConfig.antiXrayInstance.obfuscateSync(chunk.x, chunk.z, i, chunkmap.a, chunk.world); // Spigot
 
         try {
             this.inflatedBuffer = chunkmap.a;
diff --git a/src/main/java/net/minecraft/server/Packet56MapChunkBulk.java b/src/main/java/net/minecraft/server/Packet56MapChunkBulk.java
index 129dc4f..a2cd9b0 100644
--- a/src/main/java/net/minecraft/server/Packet56MapChunkBulk.java
+++ b/src/main/java/net/minecraft/server/Packet56MapChunkBulk.java
@@ -28,6 +28,7 @@ public class Packet56MapChunkBulk extends Packet {
         }
     };
     // CraftBukkit end
+    private World world; // Spigot
 
     public Packet56MapChunkBulk() {}
 
@@ -46,6 +47,9 @@ public class Packet56MapChunkBulk extends Packet {
             Chunk chunk = (Chunk) list.get(k);
             ChunkMap chunkmap = Packet51MapChunk.a(chunk, true, '\uffff');
 
+            // Spigot start
+            world = chunk.world;
+            /*
             if (buildBuffer.length < j + chunkmap.a.length) {
                 byte[] abyte = new byte[j + chunkmap.a.length];
 
@@ -54,6 +58,8 @@ public class Packet56MapChunkBulk extends Packet {
             }
 
             System.arraycopy(chunkmap.a, 0, buildBuffer, j, chunkmap.a.length);
+            */
+            // Spigot end
             j += chunkmap.a.length;
             this.c[k] = chunk.x;
             this.d[k] = chunk.z;
@@ -81,6 +87,22 @@ public class Packet56MapChunkBulk extends Packet {
         if (this.buffer != null) {
             return;
         }
+        // Spigot start
+        int finalBufferSize = 0;
+        // Obfuscate all sections
+        for (int i = 0; i < a.length; i++) {
+            world.spigotConfig.antiXrayInstance.obfuscate(c[i], d[i], a[i], inflatedBuffers[i], world);
+            finalBufferSize += inflatedBuffers[i].length;
+        }
+
+        // Now it's time to efficiently copy the chunk to the build buffer
+        buildBuffer = new byte[finalBufferSize];
+        int bufferLocation = 0;
+        for (int i = 0; i < a.length; i++) {
+            System.arraycopy(inflatedBuffers[i], 0, buildBuffer, bufferLocation, inflatedBuffers[i].length);
+            bufferLocation += inflatedBuffers[i].length;
+        }
+        // Spigot end
 
         Deflater deflater = localDeflater.get();
         deflater.reset();
diff --git a/src/main/java/net/minecraft/server/PlayerInteractManager.java b/src/main/java/net/minecraft/server/PlayerInteractManager.java
index 1243d1d..9ec8997 100644
--- a/src/main/java/net/minecraft/server/PlayerInteractManager.java
+++ b/src/main/java/net/minecraft/server/PlayerInteractManager.java
@@ -184,6 +184,7 @@ public class PlayerInteractManager {
                     this.o = j1;
                 }
             }
+            world.spigotConfig.antiXrayInstance.updateNearbyBlocks(world, i, j, k); // Spigot
         }
     }
 
diff --git a/src/main/java/org/spigotmc/AntiXray.java b/src/main/java/org/spigotmc/AntiXray.java
new file mode 100644
index 0000000..c29b789
--- /dev/null
+++ b/src/main/java/org/spigotmc/AntiXray.java
@@ -0,0 +1,203 @@
+package org.spigotmc;
+
+import gnu.trove.set.TByteSet;
+import gnu.trove.set.hash.TByteHashSet;
+import net.minecraft.server.Block;
+import net.minecraft.server.World;
+
+public class AntiXray
+{
+
+    private static final CustomTimingsHandler update = new CustomTimingsHandler( "xray - update" );
+    private static final CustomTimingsHandler obfuscate = new CustomTimingsHandler( "xray - obfuscate" );
+    /*========================================================================*/
+    // Used to keep track of which blocks to obfuscate
+    private final boolean[] obfuscateBlocks = new boolean[ Short.MAX_VALUE ];
+    // Used to select a random replacement ore
+    private byte[] replacementOres;
+
+    public AntiXray(SpigotWorldConfig config)
+    {
+        // Set all listed blocks as true to be obfuscated
+        for ( int id : config.blocks )
+        {
+            obfuscateBlocks[id] = true;
+        }
+
+        // For every block
+        TByteSet blocks = new TByteHashSet();
+        for ( int i = 0; i < obfuscateBlocks.length; i++ )
+        {
+            // If we are obfuscating it
+            if ( obfuscateBlocks[i] )
+            {
+                Block block = Block.byId[i];
+                // Check it exists and is not a tile entity
+                if ( block != null && !block.t() /* isTileEntity */ )
+                {
+                    // Add it to the set of replacement blocks
+                    blocks.add( (byte) i );
+                }
+            }
+        }
+        // Bake it to a flat array of replacements
+        replacementOres = blocks.toArray();
+    }
+
+    /**
+     * Starts the timings handler, then updates all blocks within the set radius
+     * of the given coordinate, revealing them if they are hidden ores.
+     */
+    public void updateNearbyBlocks(World world, int x, int y, int z)
+    {
+        if ( world.spigotConfig.antiXray )
+        {
+            update.startTiming();
+            updateNearbyBlocks( world, x, y, z, 2 ); // 2 is the radius, we shouldn't change it as that would make it exponentially slower
+            update.stopTiming();
+        }
+    }
+
+    /**
+     * Starts the timings handler, and then removes all non exposed ores from
+     * the chunk buffer.
+     */
+    public void obfuscateSync(int chunkX, int chunkY, int bitmask, byte[] buffer, World world)
+    {
+        if ( world.spigotConfig.antiXray )
+        {
+            obfuscate.startTiming();
+            obfuscate( chunkX, chunkY, bitmask, buffer, world );
+            obfuscate.stopTiming();
+        }
+    }
+
+    /**
+     * Removes all non exposed ores from the chunk buffer.
+     */
+    public void obfuscate(int chunkX, int chunkY, int bitmask, byte[] buffer, World world)
+    {
+        // If the world is marked as obfuscated
+        if ( world.spigotConfig.antiXray )
+        {
+            // Initial radius to search around for air
+            int initialRadius = 1;
+            // Which block in the buffer we are looking at, anywhere from 0 to 16^4
+            int index = 0;
+            // The iterator marking which random ore we should use next
+            int randomOre = 0;
+
+            // Chunk corner X and Z blocks
+            int startX = chunkX << 4;
+            int startZ = chunkY << 4;
+
+            // Chunks can have up to 16 sections
+            for ( int i = 0; i < 16; i++ )
+            {
+                // If the bitmask indicates this chunk is sent...
+                if ( ( bitmask & 1 << i ) != 0 )
+                {
+                    // Work through all blocks in the chunk, y,z,x
+                    for ( int y = 0; y < 16; y++ )
+                    {
+                        for ( int z = 0; z < 16; z++ )
+                        {
+                            for ( int x = 0; x < 16; x++ )
+                            {
+                                // Grab the block ID in the buffer.
+                                // TODO: extended IDs are not yet supported
+                                int blockId = buffer[index] & 0xFF;
+                                // Check if the block should be obfuscated
+                                if ( obfuscateBlocks[blockId] )
+                                {
+                                    // TODO: Don't really understand this, but if radius is not 0 and the world isn't loaded, bail out
+                                    if ( initialRadius != 0 && !isLoaded( world, startX + x, ( i << 4 ) + y, startZ + z, initialRadius ) )
+                                    {
+                                        continue;
+                                    }
+                                    // On the otherhand, if radius is 0, or the nearby blocks are all non air, we can obfuscate
+                                    if ( initialRadius == 0 || !hasTransparentBlockAdjacent( world, startX + x, ( i << 4 ) + y, startZ + z, initialRadius ) )
+                                    {
+                                        switch ( world.spigotConfig.engineMode )
+                                        {
+                                            case 1:
+                                                // Replace with stone
+                                                buffer[index] = (byte) Block.STONE.id;
+                                                break;
+                                            case 2:
+                                                // Replace with random ore.
+                                                if ( randomOre >= replacementOres.length )
+                                                {
+                                                    randomOre = 0;
+                                                }
+                                                buffer[index] = replacementOres[randomOre++];
+                                                break;
+                                        }
+                                    }
+                                }
+
+                                // For some reason we can get too far ahead of ourselves (concurrent modification on bulk chunks?) so if we do, just abort and move on
+                                if ( ++index >= buffer.length )
+                                {
+                                    return;
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    private void updateNearbyBlocks(World world, int x, int y, int z, int radius)
+    {
+        // If the block in question is loaded
+        if ( world.isLoaded( x, y, z ) )
+        {
+            // Get block id
+            int id = world.getTypeId( x, y, z );
+
+            // See if it needs update
+            if ( obfuscateBlocks[id] )
+            {
+                // Send the update
+                world.notify( x, y, z );
+            }
+
+            // Check other blocks for updates
+            if ( radius > 0 )
+            {
+                updateNearbyBlocks( world, x + 1, y, z, radius - 1 );
+                updateNearbyBlocks( world, x - 1, y, z, radius - 1 );
+                updateNearbyBlocks( world, x, y + 1, z, radius - 1 );
+                updateNearbyBlocks( world, x, y - 1, z, radius - 1 );
+                updateNearbyBlocks( world, x, y, z + 1, radius - 1 );
+                updateNearbyBlocks( world, x, y, z - 1, radius - 1 );
+            }
+        }
+    }
+
+    private static boolean isLoaded(World world, int x, int y, int z, int radius)
+    {
+        return world.isLoaded( x, y, z )
+                || ( radius > 0
+                && ( isLoaded( world, x + 1, y, z, radius - 1 )
+                || isLoaded( world, x - 1, y, z, radius - 1 )
+                || isLoaded( world, x, y + 1, z, radius - 1 )
+                || isLoaded( world, x, y - 1, z, radius - 1 )
+                || isLoaded( world, x, y, z + 1, radius - 1 )
+                || isLoaded( world, x, y, z - 1, radius - 1 ) ) );
+    }
+
+    private static boolean hasTransparentBlockAdjacent(World world, int x, int y, int z, int radius)
+    {
+        return !Block.l( world.getTypeId( x, y, z ) ) /* isSolidBlock */
+                || ( radius > 0
+                && ( hasTransparentBlockAdjacent( world, x + 1, y, z, radius - 1 )
+                || hasTransparentBlockAdjacent( world, x - 1, y, z, radius - 1 )
+                || hasTransparentBlockAdjacent( world, x, y + 1, z, radius - 1 )
+                || hasTransparentBlockAdjacent( world, x, y - 1, z, radius - 1 )
+                || hasTransparentBlockAdjacent( world, x, y, z + 1, radius - 1 )
+                || hasTransparentBlockAdjacent( world, x, y, z - 1, radius - 1 ) ) );
+    }
+}
diff --git a/src/main/java/org/spigotmc/SpigotWorldConfig.java b/src/main/java/org/spigotmc/SpigotWorldConfig.java
index 81879e6..0a304e8 100644
--- a/src/main/java/org/spigotmc/SpigotWorldConfig.java
+++ b/src/main/java/org/spigotmc/SpigotWorldConfig.java
@@ -1,5 +1,6 @@
 package org.spigotmc;
 
+import java.util.Arrays;
 import java.util.List;
 import org.bukkit.Bukkit;
 import org.bukkit.configuration.file.YamlConfiguration;
@@ -123,4 +124,25 @@ public class SpigotWorldConfig
         viewDistance = getInt( "view-distance", Bukkit.getViewDistance() );
         log( "View Distance: " + viewDistance );
     }
+
+    public boolean antiXray = true;
+    public int engineMode = 1;
+    public List<Integer> blocks = Arrays.asList( new Integer[]
+    {
+        1, 5, 14, 15, 16, 21, 48, 49, 54, 56, 73, 74, 82, 129, 130
+    } );
+    public AntiXray antiXrayInstance;
+    private void antiXray()
+    {
+        antiXray = getBoolean( "anti-xray.enabled", antiXray );
+        log( "Anti X-Ray: " + antiXray );
+
+        engineMode = getInt( "anti-xray.engine-mode", engineMode );
+        log( "\tEngine Mode: " + engineMode );
+
+        blocks = getList( "anti-xray.blocks", blocks );
+        log( "\tBlocks: " + blocks );
+        
+        antiXrayInstance = new AntiXray( this );
+    }
 }
-- 
1.8.1.2