Added safety checks to not send garbage bits

Author: TwoTenPvP

MLAPI/Data/NetworkConfig.cs

@@ -221,6 +221,7 @@ public string ToBase64()
                     writer.WriteBool(config.EnableSceneSwitching);
                     writer.WriteBool(config.EnableTimeResync);
                     writer.WriteBits((byte)config.AttributeMessageMode, 3);
+                    stream.ZeroLastByteGarbageBits();
 
                     return Convert.ToBase64String(stream.ToArray());
                 }
@@ -353,7 +354,7 @@ public ulong GetConfig(bool cache = true)
                     writer.WriteBool(EnableSceneSwitching);
                     writer.WriteBool(SignKeyExchange);
                     writer.WriteBits((byte)AttributeMessageMode, 3);
-                    writer.WritePadBits();
+                    stream.ZeroLastByteGarbageBits();
 
                     if (cache)
                     {

MLAPI/NetworkingManagerComponents/Binary/BitStream.cs

@@ -439,6 +439,16 @@ public byte[] ToArray()
             return copy;
         }
 
+        /// <summary>
+        /// Sets the unused bits of the last byte to 0s
+        /// </summary>
+        public void ZeroLastByteGarbageBits()
+        {
+            if (BitAligned) return;
+
+            target[Length] &= (byte)~(0xFF << (int)(BitLength % 8));
+        }
+
         /// <summary>
         /// Returns hex encoded version of the buffer
         /// </summary>

MLAPI/NetworkingManagerComponents/Core/InternalMessageHandler.Send.cs

@@ -1,6 +1,4 @@
-using System.IO;
-using System.Security.Cryptography;
-using MLAPI.Data;
+using MLAPI.Data;
 using MLAPI.Profiling;
 using MLAPI.Serialization;
 
@@ -10,7 +8,10 @@ internal static partial class InternalMessageHandler
     {
         internal static void Send(uint clientId, byte messageType, string channelName, BitStream messageStream, SecuritySendFlags flags, bool skipQueue = false)
         {
+            messageStream.ZeroLastByteGarbageBits();
+
             if (NetworkingManager.singleton.isServer && clientId == NetworkingManager.singleton.ServerClientId) return;
+
             using (BitStream stream = MessageManager.WrapMessage(messageType, clientId, messageStream, flags))
             {
                 NetworkProfiler.StartEvent(TickType.Send, (uint)stream.Length, channelName, MLAPIConstants.MESSAGE_NAMES[messageType]);
@@ -37,6 +38,8 @@ internal static void Send(byte messageType, string channelName, BitStream messag
             }
             else
             {
+                messageStream.ZeroLastByteGarbageBits();
+
                 using (BitStream stream = MessageManager.WrapMessage(messageType, 0, messageStream, flags))
                 {
                     NetworkProfiler.StartEvent(TickType.Send, (uint)stream.Length, channelName, MLAPIConstants.MESSAGE_NAMES[messageType]);
@@ -68,6 +71,8 @@ internal static void Send(byte messageType, string channelName, uint clientIdToI
             }
             else
             {
+                messageStream.ZeroLastByteGarbageBits();
+
                 using (BitStream stream = MessageManager.WrapMessage(messageType, 0, messageStream, flags))
                 {
                     NetworkProfiler.StartEvent(TickType.Send, (uint)stream.Length, channelName, MLAPIConstants.MESSAGE_NAMES[messageType]);