add patch for negative infinity and infinity attributes causing disconnect

src/main/java/ca/momothereal/mojangson/MojangsonFinder.java

@@ -0,0 +1,21 @@
+package ca.momothereal.mojangson;
+
+import ca.momothereal.mojangson.ex.MojangsonParseException;
+import ca.momothereal.mojangson.value.*;
+
+import static ca.momothereal.mojangson.MojangsonToken.*;
+
+public class MojangsonFinder {
+
+    /**
+     * Automatically detects the appropriate MojangsonValue from the given value.
+     * @param value The value to parse
+     * @return The resulting MojangsonValue. If the type couldn't be found, it falls back to MojangsonString
+     * @throws MojangsonParseException if the given value could not be parsed
+     */
+    public static MojangsonValue readFromValue(String value) throws MojangsonParseException {
+        MojangsonValue val = new MojangsonString();
+        val.read(value);
+        return val;
+    }
+}

src/main/java/ca/momothereal/mojangson/MojangsonToken.java

@@ -0,0 +1,47 @@
+package ca.momothereal.mojangson;
+
+public enum MojangsonToken {
+
+    COMPOUND_START(0, "Compound_Start", '{'),
+    COMPOUND_END(1, "Compound_End", '}'),
+    ELEMENT_SEPERATOR(2, "Element_Seperator", ','),
+    ARRAY_START(3, "Array_Start", '['),
+    ARRAY_END(4, "Array_End", ']'),
+    ELEMENT_PAIR_SEPERATOR(5, "Pair_Seperator", ':'),
+
+    STRING_QUOTES(6, "String_Quotes", '\"'),
+    DOUBLE_SUFFIX(8, "Double_Suffix", 'd'),
+    BYTE_SUFFIX(9, "Byte_Suffix", 'b'),
+    FLOAT_SUFFIX(10, "Float_Suffix", 'f'),
+    SHORT_SUFFIX(11, "Short_Suffix", 's'),
+    LONG_SUFFIX(12, "Long_Suffix", 'l'),
+
+    WHITE_SPACE(13, "WhiteSpace", ' ');
+
+    private int id;
+    private String name;
+    private char symbol;
+
+    MojangsonToken(int id, String name, char symbol) {
+        this.id = id;
+        this.name = name;
+        this.symbol = symbol;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public char getSymbol() {
+        return symbol;
+    }
+
+    @Override
+    public String toString() {
+        return String.valueOf(symbol);
+    }
+}

src/main/java/ca/momothereal/mojangson/ex/MojangsonParseException.java

@@ -0,0 +1,35 @@
+package ca.momothereal.mojangson.ex;
+
+public class MojangsonParseException extends Exception {
+
+    private ParseExceptionReason reason;
+
+    public MojangsonParseException(String message, ParseExceptionReason reason) {
+        super(message);
+        this.reason = reason;
+    }
+
+    public ParseExceptionReason getReason() {
+        return reason;
+    }
+
+    @Override
+    public String getMessage() {
+        return reason.getMessage() + ": " + super.getMessage();
+    }
+
+    public enum ParseExceptionReason {
+        INVALID_FORMAT_NUM("Given value is not numerical"),
+        UNEXPECTED_SYMBOL("Unexpected symbol in Mojangson string");
+
+        private String message;
+
+        ParseExceptionReason(String message) {
+            this.message = message;
+        }
+
+        public String getMessage() {
+            return message;
+        }
+    }
+}

src/main/java/ca/momothereal/mojangson/value/MojangsonCompound.java

@@ -0,0 +1,118 @@
+package ca.momothereal.mojangson.value;
+
+import ca.momothereal.mojangson.MojangsonFinder;
+import ca.momothereal.mojangson.ex.MojangsonParseException;
+
+import java.util.*;
+
+import static ca.momothereal.mojangson.MojangsonToken.*;
+
+public class MojangsonCompound extends HashMap<String, List<MojangsonValue>> implements MojangsonValue<Map<String, MojangsonValue>> {
+
+    private final int C_COMPOUND_START = 0;      // Parsing context
+    private final int C_COMPOUND_PAIR_KEY = 1;   // Parsing context
+    private final int C_COMPOUND_PAIR_VALUE = 2; // Parsing context
+
+    public MojangsonCompound() {
+
+    }
+
+    public MojangsonCompound(Map map) {
+        super(map);
+    }
+
+    @Override
+    public void write(StringBuilder builder) {
+        builder.append(COMPOUND_START);
+        boolean start = true;
+
+        for (String key : keySet()) {
+            if (start) {
+                start = false;
+            } else {
+                builder.append(ELEMENT_SEPERATOR);
+            }
+
+            builder.append(key).append(ELEMENT_PAIR_SEPERATOR);
+            List<MojangsonValue> value = get(key);
+            for(MojangsonValue val : value)
+            {
+                val.write(builder);
+            }
+        }
+        builder.append(COMPOUND_END);
+    }
+
+    @Override
+    public void read(String string) throws MojangsonParseException {
+        int context = C_COMPOUND_START;
+        String tmp_key = "", tmp_val = "";
+        int scope = 0;
+        boolean inString = false;
+
+        for (int index = 0; index < string.length(); index++) {
+            Character character = string.charAt(index);
+
+            if (character == STRING_QUOTES.getSymbol()) {
+                inString = !inString;
+            }
+            if (character == WHITE_SPACE.getSymbol()) {
+                if (!inString)
+                    continue;
+            }
+            if ((character == COMPOUND_START.getSymbol() || character == ARRAY_START.getSymbol()) && !inString) {
+                scope++;
+            }
+            if ((character == COMPOUND_END.getSymbol() || character == ARRAY_END.getSymbol()) && !inString) {
+                scope--;
+            }
+            if (context == C_COMPOUND_START) {
+                if (character != COMPOUND_START.getSymbol()) {
+                    parseException(index, character);
+                    return;
+                }
+                context++;
+                continue;
+            }
+            if (context == C_COMPOUND_PAIR_KEY) {
+                if (character == ELEMENT_PAIR_SEPERATOR.getSymbol() && scope <= 1) {
+                    context++;
+                    continue;
+                }
+                tmp_key += character;
+                continue;
+            }
+            if (context == C_COMPOUND_PAIR_VALUE) {
+                if ((character == ELEMENT_SEPERATOR.getSymbol() || character == COMPOUND_END.getSymbol()) && scope <= 1 && !inString) {
+                    context = C_COMPOUND_PAIR_KEY;
+                    computeIfAbsent(tmp_key, k -> new ArrayList<>()).add(MojangsonFinder.readFromValue(tmp_val));
+                    tmp_key = tmp_val = "";
+                    continue;
+                }
+                tmp_val += character;
+            }
+        }
+    }
+
+    @Override
+    public Map<String, MojangsonValue> getValue() {
+        HashMap<String, MojangsonValue> hack = new HashMap<>();
+        for(String string : keySet())
+        {
+            for(MojangsonValue value : get(string))
+            {
+                hack.put(string, value);
+            }
+        }
+        return hack;
+    }
+
+    @Override
+    public Class getValueClass() {
+        return Map.class;
+    }
+
+    private void parseException(int index, char symbol) throws MojangsonParseException {
+        throw new MojangsonParseException("Index: " + index + ", symbol: \'" + symbol + "\'", MojangsonParseException.ParseExceptionReason.UNEXPECTED_SYMBOL);
+    }
+}

src/main/java/ca/momothereal/mojangson/value/MojangsonString.java

@@ -0,0 +1,46 @@
+package ca.momothereal.mojangson.value;
+
+import ca.momothereal.mojangson.MojangsonToken;
+import ca.momothereal.mojangson.ex.MojangsonParseException;
+
+public class MojangsonString implements MojangsonValue<String> {
+    private String value;
+
+    public MojangsonString() {
+
+    }
+
+    public MojangsonString(String value) {
+        this.value = value;
+    }
+
+    public String getValue() {
+        return value;
+    }
+
+    public void setValue(String value) {
+        this.value = value;
+    }
+
+    @Override
+    public void write(StringBuilder builder) {
+        builder.append(MojangsonToken.STRING_QUOTES).append(value).append(MojangsonToken.STRING_QUOTES);
+    }
+
+    @Override
+    public Class getValueClass() {
+        return String.class;
+    }
+
+    @Override
+    public void read(String string) throws MojangsonParseException {
+        Character lastChar = string.charAt(string.length() - 1);
+        Character firstChar = string.charAt(0);
+
+        if (firstChar == MojangsonToken.STRING_QUOTES.getSymbol() && lastChar == MojangsonToken.STRING_QUOTES.getSymbol()) {
+            value = string.substring(1, string.length() - 1);
+        } else {
+            value = string;
+        }
+    }
+}

src/main/java/ca/momothereal/mojangson/value/MojangsonValue.java

@@ -0,0 +1,36 @@
+package ca.momothereal.mojangson.value;
+
+import ca.momothereal.mojangson.ex.MojangsonParseException;
+
+/**
+ * Represents a value inside a compound or array.
+ * @param <T> The type of value this MojangsonValue holds
+ */
+public interface MojangsonValue<T> {
+
+    /**
+     * Writes the value to a StringBuilder buffer.
+     * @param builder The buffer to write to
+     */
+    void write(StringBuilder builder);
+
+    /**
+     * Parses and updates the current value to the given string representation
+     * @param string The string representation of the value
+     * @throws MojangsonParseException if the given value cannot be parsed
+     */
+    void read(String string) throws MojangsonParseException;
+
+    /**
+     * Gets the current literal value
+     * @return The current literal value of the MojangsonValue
+     */
+    T getValue();
+
+    /**
+     * Gets the literal value's class
+     * @return The literal value's class
+     */
+    Class getValueClass();
+
+}

src/main/java/me/totalfreedom/totalfreedommod/MovementValidator.java

@@ -1,11 +1,24 @@
 package me.totalfreedom.totalfreedommod;
 
+import ca.momothereal.mojangson.ex.MojangsonParseException;
+import ca.momothereal.mojangson.value.MojangsonCompound;
+import ca.momothereal.mojangson.value.MojangsonValue;
+import net.minecraft.server.v1_12_R1.NBTTagCompound;
+import net.minecraft.server.v1_12_R1.NBTTagList;
+import org.bukkit.ChatColor;
+import org.bukkit.Material;
+import org.bukkit.craftbukkit.v1_12_R1.inventory.CraftItemStack;
 import org.bukkit.entity.Player;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.EventPriority;
+import org.bukkit.event.player.PlayerItemHeldEvent;
 import org.bukkit.event.player.PlayerLoginEvent;
 import org.bukkit.event.player.PlayerMoveEvent;
 import org.bukkit.event.player.PlayerTeleportEvent;
+import org.bukkit.inventory.ItemStack;
+
+import java.util.List;
+import java.util.Objects;
 
 public class MovementValidator extends FreedomService
 {
@@ -48,6 +61,43 @@ public class MovementValidator extends FreedomService
             event.setCancelled(true);
             player.teleport(player.getWorld().getSpawnLocation());
         }
+
+        if (exploitItem(event.getPlayer().getInventory().getHelmet()))
+        {
+            event.getPlayer().getInventory().setHelmet(new ItemStack(Material.AIR));
+            event.getPlayer().sendMessage(ChatColor.RED + "An item with both negative infinity and positive infinity attributes was cleared from your helmet slot.");
+            event.setCancelled(true);
+        }
+        if (exploitItem(event.getPlayer().getInventory().getBoots()))
+        {
+            event.getPlayer().getInventory().setBoots(new ItemStack(Material.AIR));
+            event.getPlayer().sendMessage(ChatColor.RED + "An item with both negative infinity and positive infinity attributes was cleared from your boots slot.");
+            event.setCancelled(true);
+        }
+        if (exploitItem(event.getPlayer().getInventory().getLeggings()))
+        {
+            event.getPlayer().getInventory().setLeggings(new ItemStack(Material.AIR));
+            event.getPlayer().sendMessage(ChatColor.RED + "An item with both negative infinity and positive infinity attributes was cleared from your leggings slot.");
+            event.setCancelled(true);
+        }
+        if (exploitItem(event.getPlayer().getInventory().getChestplate()))
+        {
+            event.getPlayer().getInventory().setChestplate(new ItemStack(Material.AIR));
+            event.getPlayer().sendMessage(ChatColor.RED + "An item with both negative infinity and positive infinity attributes was cleared from your chestplate slot.");
+            event.setCancelled(true);
+        }
+        if (exploitItem(event.getPlayer().getInventory().getItemInMainHand()))
+        {
+            event.getPlayer().getInventory().setItemInMainHand(new ItemStack(Material.AIR));
+            event.getPlayer().sendMessage(ChatColor.RED + "An item with both negative infinity and positive infinity attributes was cleared from your hand.");
+            event.setCancelled(true);
+        }
+        if (exploitItem(event.getPlayer().getInventory().getItemInOffHand()))
+        {
+            event.getPlayer().getInventory().setItemInOffHand(new ItemStack(Material.AIR));
+            event.getPlayer().sendMessage(ChatColor.RED + "An item with both negative infinity and positive infinity attributes was cleared from your offhand.");
+            event.setCancelled(true);
+        }
     }
 
     @EventHandler(priority = EventPriority.HIGH)
@@ -62,4 +112,73 @@ public class MovementValidator extends FreedomService
         }
     }
 
+    @EventHandler
+    public void onPlayerHoldItem(PlayerItemHeldEvent event)
+    {
+        if (exploitItem(event.getPlayer().getInventory().getItemInMainHand()))
+        {
+            event.getPlayer().getInventory().setItemInMainHand(new ItemStack(Material.AIR));
+            event.getPlayer().sendMessage(ChatColor.RED + "An item with both negative infinity and positive infinity attributes was cleared from your hand.");
+        }
+        if (exploitItem(event.getPlayer().getInventory().getItemInOffHand()))
+        {
+            event.getPlayer().getInventory().setItemInOffHand(new ItemStack(Material.AIR));
+            event.getPlayer().sendMessage(ChatColor.RED + "An item with both negative infinity and positive infinity attributes was cleared from your offhand.");
+        }
+    }
+
+    private Boolean exploitItem(ItemStack item)
+    {
+        net.minecraft.server.v1_12_R1.ItemStack nmsStack = CraftItemStack.asNMSCopy(item);
+        NBTTagList modifiers = getAttributeList(nmsStack);
+        MojangsonCompound compound = new MojangsonCompound();
+        boolean foundNegative = false;
+        boolean foundPositive = false;
+        try
+        {
+            String mod = modifiers.toString();
+            String fancy = ("{" + (mod.substring(1, mod.length() - 1).replace("{", "").replace("}", "")) + "}");
+            compound.read(fancy);
+            for (String key : compound.keySet())
+            {
+                if (Objects.equals(key, "Amount")) //null-safe .equals()
+                {
+                    List<MojangsonValue> values = compound.get(key);
+                    for (MojangsonValue val : values)
+                    {
+                        if (val.getValue().toString().equals("Infinityd"))
+                        {
+                            foundPositive = true;
+                        }
+                        if (val.getValue().toString().equals("-Infinityd"))
+                        {
+                            foundNegative = true;
+                        }
+                    }
+                }
+            }
+        }
+        catch (MojangsonParseException e)
+        {
+            e.printStackTrace();
+        }
+        return foundNegative && foundPositive;
+    }
+
+
+    private NBTTagList getAttributeList(net.minecraft.server.v1_12_R1.ItemStack stack)
+    {
+        if (stack.getTag() == null)
+        {
+            stack.setTag(new NBTTagCompound());
+        }
+        NBTTagList attr = stack.getTag().getList("AttributeModifiers", 10);
+        if (attr == null)
+        {
+            stack.getTag().set("AttributeModifiers", new NBTTagList());
+        }
+        return stack.getTag().getList("AttributeModifiers", 10);
+    }
 }
+
+