Merge c5824f39e1 into 1187a59b18

Assets/Mirror/Tests/Editor/Transports/EncryptionTransportTransportTest.cs

@@ -22,7 +22,7 @@ public void Setup()
             GameObject gameObject = new GameObject();
 
             encryption = gameObject.AddComponent<EncryptionTransport>();
-            encryption.inner = inner;
+            encryption.Inner = inner;
         }
 
         [TearDown]

Assets/Mirror/Transports/Encryption/Editor/EncryptionTransportInspector.cs

@@ -17,11 +17,11 @@ public class EncryptionTransportInspector : UnityEditor.Editor
 
         void OnEnable()
         {
-            innerProperty = serializedObject.FindProperty("inner");
-            clientValidatesServerPubKeyProperty = serializedObject.FindProperty("clientValidateServerPubKey");
-            clientTrustedPubKeySignaturesProperty = serializedObject.FindProperty("clientTrustedPubKeySignatures");
-            serverKeypairPathProperty = serializedObject.FindProperty("serverKeypairPath");
-            serverLoadKeyPairFromFileProperty = serializedObject.FindProperty("serverLoadKeyPairFromFile");
+            innerProperty = serializedObject.FindProperty("Inner");
+            clientValidatesServerPubKeyProperty = serializedObject.FindProperty("ClientValidateServerPubKey");
+            clientTrustedPubKeySignaturesProperty = serializedObject.FindProperty("ClientTrustedPubKeySignatures");
+            serverKeypairPathProperty = serializedObject.FindProperty("ServerKeypairPath");
+            serverLoadKeyPairFromFileProperty = serializedObject.FindProperty("ServerLoadKeyPairFromFile");
         }
 
         public override void OnInspectorGUI()
@@ -77,5 +77,8 @@ public override void OnInspectorGUI()
 
             serializedObject.ApplyModifiedProperties();
         }
+
+        [CustomEditor(typeof(ThreadedEncryptionTransport), true)]
+        class EncryptionThreadedTransportInspector : EncryptionTransportInspector {}
     }
 }

Assets/Mirror/Transports/Encryption/EncryptedConnection.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Security.Cryptography;
 using System.Text;
+using System.Threading;
 using Mirror.BouncyCastle.Crypto;
 using Mirror.BouncyCastle.Crypto.Agreement;
 using Mirror.BouncyCastle.Crypto.Digests;
@@ -14,32 +15,32 @@ namespace Mirror.Transports.Encryption
     public class EncryptedConnection
     {
         // 256-bit key
-        private const int KeyLength = 32;
+        const int KeyLength = 32;
         // 512-bit salt for the key derivation function
-        private const int HkdfSaltSize = KeyLength * 2;
+        const int HkdfSaltSize = KeyLength * 2;
 
         // Info tag for the HKDF, this just adds more entropy
-        private static readonly byte[] HkdfInfo = Encoding.UTF8.GetBytes("Mirror/EncryptionTransport");
+        static readonly byte[] HkdfInfo = Encoding.UTF8.GetBytes("Mirror/EncryptionTransport");
 
         // fixed size of the unique per-packet nonce. Defaults to 12 bytes/96 bits (not recommended to be changed)
-        private const int NonceSize = 12;
+        const int NonceSize = 12;
 
         // this is the size of the "checksum" included in each encrypted payload
         // 16 bytes/128 bytes is the recommended value for best security
         // can be reduced to 12 bytes for a small space savings, but makes encryption slightly weaker.
         // Setting it lower than 12 bytes is not recommended
-        private const int MacSizeBytes = 16;
+        const int MacSizeBytes = 16;
 
-        private const int MacSizeBits = MacSizeBytes * 8;
+        const int MacSizeBits = MacSizeBytes * 8;
 
         // How much metadata overhead we have for regular packets
         public const int Overhead = sizeof(OpCodes) + MacSizeBytes + NonceSize;
 
         // After how many seconds of not receiving a handshake packet we should time out
-        private const double DurationTimeout = 2; // 2s
+        const double DurationTimeout = 2; // 2s
 
         // After how many seconds to assume the last handshake packet got lost and to resend another one
-        private const double DurationResend = 0.05; // 50ms
+        const double DurationResend = 0.05; // 50ms
 
 
         // Static fields for allocation efficiency, makes this not thread safe
@@ -48,20 +49,19 @@ public class EncryptedConnection
         // Set up a global cipher instance, it is initialised/reset before use
         // (AesFastEngine used to exist, but was removed due to side channel issues)
         // use AesUtilities.CreateEngine here as it'll pick the hardware accelerated one if available (which is will not be unless on .net core)
-        private static readonly GcmBlockCipher Cipher = new GcmBlockCipher(AesUtilities.CreateEngine());
+        static readonly ThreadLocal<GcmBlockCipher> Cipher = new ThreadLocal<GcmBlockCipher>(() => new GcmBlockCipher(AesUtilities.CreateEngine()));
 
         // Set up a global HKDF with a SHA-256 digest
-        private static readonly HkdfBytesGenerator Hkdf = new HkdfBytesGenerator(new Sha256Digest());
+        static readonly ThreadLocal<HkdfBytesGenerator> Hkdf = new ThreadLocal<HkdfBytesGenerator>(() => new HkdfBytesGenerator(new Sha256Digest()));
 
         // Global byte array to store nonce sent by the remote side, they're used immediately after
-        private static readonly byte[] ReceiveNonce = new byte[NonceSize];
+        static readonly ThreadLocal<byte[]> ReceiveNonce = new ThreadLocal<byte[]>(() => new byte[NonceSize]);
 
         // Buffer for the remote salt, as bouncycastle needs to take a byte[] *rolls eyes*
-        private static byte[] _tmpRemoteSaltBuffer = new byte[HkdfSaltSize];
+        static readonly ThreadLocal<byte[]> TMPRemoteSaltBuffer = new ThreadLocal<byte[]>(() => new byte[HkdfSaltSize]);
+
         // buffer for encrypt/decrypt operations, resized larger as needed
-        // this is also the buffer that will be returned to mirror via ArraySegment
-        // so any thread safety concerns would need to take extra care here
-        private static byte[] _tmpCryptBuffer = new byte[2048];
+        static ThreadLocal<byte[]> TMPCryptBuffer = new ThreadLocal<byte[]>(() => new byte[2048]);
 
         // packet headers
         enum OpCodes : byte
@@ -70,7 +70,7 @@ enum OpCodes : byte
             Data = 1,
             HandshakeStart = 2,
             HandshakeAck = 3,
-            HandshakeFin = 4,
+            HandshakeFin = 4
         }
 
         enum State
@@ -91,37 +91,37 @@ enum State
             Ready
         }
 
-        private State _state = State.WaitingHandshake;
+        State state = State.WaitingHandshake;
 
         // Key exchange confirmed and data can be sent freely
-        public bool IsReady => _state == State.Ready;
+        public bool IsReady => state == State.Ready;
         // Callback to send off encrypted data
-        private Action<ArraySegment<byte>, int> _send;
+        readonly Action<ArraySegment<byte>, int> send;
         // Callback when received data has been decrypted
-        private Action<ArraySegment<byte>, int> _receive;
+        readonly Action<ArraySegment<byte>, int> receive;
         // Callback when the connection becomes ready
-        private Action _ready;
+        readonly Action ready;
         // On-error callback, disconnect expected
-        private Action<TransportError, string> _error;
+        readonly Action<TransportError, string> error;
         // Optional callback to validate the remotes public key, validation on one side is necessary to ensure MITM resistance
         // (usually client validates the server key)
-        private Func<PubKeyInfo, bool> _validateRemoteKey;
+        readonly Func<PubKeyInfo, bool> validateRemoteKey;
         // Our asymmetric credentials for the initial DH exchange
-        private EncryptionCredentials _credentials;
-        private byte[] _hkdfSalt;
+        EncryptionCredentials credentials;
+        readonly byte[] hkdfSalt;
 
         // After no handshake packet in this many seconds, the handshake fails
-        private double _handshakeTimeout;
+        double handshakeTimeout;
         // When to assume the last handshake packet got lost and to resend another one
-        private double _nextHandshakeResend;
+        double nextHandshakeResend;
 
 
         // we can reuse the _cipherParameters here since the nonce is stored as the byte[] reference we pass in
         // so we can update it without creating a new AeadParameters instance
         // this might break in the future! (will cause bad data)
-        private byte[] _nonce = new byte[NonceSize];
-        private AeadParameters _cipherParametersEncrypt;
-        private AeadParameters _cipherParametersDecrypt;
+        byte[] nonce = new byte[NonceSize];
+        AeadParameters cipherParametersEncrypt;
+        AeadParameters cipherParametersDecrypt;
 
 
         /*
@@ -130,7 +130,7 @@ enum State
          *
          * The client does this, since the fin is not acked explicitly, but by receiving data to decrypt
          */
-        private readonly bool _sendsFirst;
+        readonly bool sendsFirst;
 
         public EncryptedConnection(EncryptionCredentials credentials,
             bool isClient,
@@ -140,28 +140,24 @@ public EncryptedConnection(EncryptionCredentials credentials,
             Action<TransportError, string> errorAction,
             Func<PubKeyInfo, bool> validateRemoteKey = null)
         {
-            _credentials = credentials;
-            _sendsFirst = isClient;
-            if (!_sendsFirst)
-            {
+            this.credentials = credentials;
+            sendsFirst = isClient;
+            if (!sendsFirst)
                 // salt is controlled by the server
-                _hkdfSalt = GenerateSecureBytes(HkdfSaltSize);
-            }
-            _send = sendAction;
-            _receive = receiveAction;
-            _ready = readyAction;
-            _error = errorAction;
-            _validateRemoteKey = validateRemoteKey;
+                hkdfSalt = GenerateSecureBytes(HkdfSaltSize);
+            send = sendAction;
+            receive = receiveAction;
+            ready = readyAction;
+            error = errorAction;
+            this.validateRemoteKey = validateRemoteKey;
         }
 
         // Generates a random starting nonce
-        private static byte[] GenerateSecureBytes(int size)
+        static byte[] GenerateSecureBytes(int size)
         {
             byte[] bytes = new byte[size];
             using (RandomNumberGenerator rng = RandomNumberGenerator.Create())
-            {
                 rng.GetBytes(bytes);
-            }
 
             return bytes;
         }
@@ -170,7 +166,7 @@ public void OnReceiveRaw(ArraySegment<byte> data, int channel)
         {
             if (data.Count < 1)
             {
-                _error(TransportError.Unexpected, "Received empty packet");
+                error(TransportError.Unexpected, "Received empty packet");
                 return;
             }
 
@@ -181,94 +177,80 @@ public void OnReceiveRaw(ArraySegment<byte> data, int channel)
                 {
                     case OpCodes.Data:
                         // first sender ready is implicit when data is received
-                        if (_sendsFirst && _state == State.WaitingHandshakeReply)
-                        {
+                        if (sendsFirst && state == State.WaitingHandshakeReply)
                             SetReady();
-                        }
                         else if (!IsReady)
-                        {
-                            _error(TransportError.Unexpected, "Unexpected data while not ready.");
-                        }
+                            error(TransportError.Unexpected, "Unexpected data while not ready.");
 
                         if (reader.Remaining < Overhead)
                         {
-                            _error(TransportError.Unexpected, "received data packet smaller than metadata size");
+                            error(TransportError.Unexpected, "received data packet smaller than metadata size");
                             return;
                         }
 
                         ArraySegment<byte> ciphertext = reader.ReadBytesSegment(reader.Remaining - NonceSize);
-                        reader.ReadBytes(ReceiveNonce, NonceSize);
+                        reader.ReadBytes(ReceiveNonce.Value, NonceSize);
 
                         Profiler.BeginSample("EncryptedConnection.Decrypt");
                         ArraySegment<byte> plaintext = Decrypt(ciphertext);
                         Profiler.EndSample();
                         if (plaintext.Count == 0)
-                        {
                             // error
                             return;
-                        }
-                        _receive(plaintext, channel);
+                        receive(plaintext, channel);
                         break;
                     case OpCodes.HandshakeStart:
-                        if (_sendsFirst)
+                        if (sendsFirst)
                         {
-                            _error(TransportError.Unexpected, "Received HandshakeStart packet, we don't expect this.");
+                            error(TransportError.Unexpected, "Received HandshakeStart packet, we don't expect this.");
                             return;
                         }
 
-                        if (_state == State.WaitingHandshakeReply)
-                        {
+                        if (state == State.WaitingHandshakeReply)
                             // this is fine, packets may arrive out of order
                             return;
-                        }
 
-                        _state = State.WaitingHandshakeReply;
+                        state = State.WaitingHandshakeReply;
                         ResetTimeouts();
-                        CompleteExchange(reader.ReadBytesSegment(reader.Remaining), _hkdfSalt);
+                        CompleteExchange(reader.ReadBytesSegment(reader.Remaining), hkdfSalt);
                         SendHandshakeAndPubKey(OpCodes.HandshakeAck);
                         break;
                     case OpCodes.HandshakeAck:
-                        if (!_sendsFirst)
+                        if (!sendsFirst)
                         {
-                            _error(TransportError.Unexpected, "Received HandshakeAck packet, we don't expect this.");
+                            error(TransportError.Unexpected, "Received HandshakeAck packet, we don't expect this.");
                             return;
                         }
 
                         if (IsReady)
-                        {
                             // this is fine, packets may arrive out of order
                             return;
-                        }
 
-                        if (_state == State.WaitingHandshakeReply)
-                        {
+                        if (state == State.WaitingHandshakeReply)
                             // this is fine, packets may arrive out of order
                             return;
-                        }
 
 
-                        _state = State.WaitingHandshakeReply;
+                        state = State.WaitingHandshakeReply;
                         ResetTimeouts();
-                        reader.ReadBytes(_tmpRemoteSaltBuffer, HkdfSaltSize);
-                        CompleteExchange(reader.ReadBytesSegment(reader.Remaining), _tmpRemoteSaltBuffer);
+                        reader.ReadBytes(TMPRemoteSaltBuffer.Value, HkdfSaltSize);
+                        CompleteExchange(reader.ReadBytesSegment(reader.Remaining), TMPRemoteSaltBuffer.Value);
                         SendHandshakeFin();
                         break;
                     case OpCodes.HandshakeFin:
-                        if (_sendsFirst)
+                        if (sendsFirst)
                         {
-                            _error(TransportError.Unexpected, "Received HandshakeFin packet, we don't expect this.");
+                            error(TransportError.Unexpected, "Received HandshakeFin packet, we don't expect this.");
                             return;
                         }
 
                         if (IsReady)
-                        {
                             // this is fine, packets may arrive out of order
                             return;
-                        }
 
-                        if (_state != State.WaitingHandshakeReply)
+                        if (state != State.WaitingHandshakeReply)
                         {
-                            _error(TransportError.Unexpected,
+                            error(TransportError.Unexpected,
                                 "Received HandshakeFin packet, we didn't expect this yet.");
                             return;
                         }
@@ -277,24 +259,25 @@ public void OnReceiveRaw(ArraySegment<byte> data, int channel)
 
                         break;
                     default:
-                        _error(TransportError.InvalidReceive, $"Unhandled opcode {(byte)opcode:x}");
+                        error(TransportError.InvalidReceive, $"Unhandled opcode {(byte)opcode:x}");
                         break;
                 }
             }
         }
-        private void SetReady()
+
+        void SetReady()
         {
             // done with credentials, null out the reference
-            _credentials = null;
+            credentials = null;
 
-            _state = State.Ready;
-            _ready();
+            state = State.Ready;
+            ready();
         }
 
-        private void ResetTimeouts()
+        void ResetTimeouts()
         {
-            _handshakeTimeout = 0;
-            _nextHandshakeResend = -1;
+            handshakeTimeout = 0;
+            nextHandshakeResend = -1;
         }
 
         public void Send(ArraySegment<byte> data, int channel)
@@ -307,161 +290,149 @@ public void Send(ArraySegment<byte> data, int channel)
                 Profiler.EndSample();
 
                 if (encrypted.Count == 0)
-                {
                     // error
                     return;
-                }
                 writer.WriteBytes(encrypted.Array, 0, encrypted.Count);
                 // write nonce after since Encrypt will update it
-                writer.WriteBytes(_nonce, 0, NonceSize);
-                _send(writer.ToArraySegment(), channel);
+                writer.WriteBytes(nonce, 0, NonceSize);
+                send(writer.ToArraySegment(), channel);
             }
         }
 
-        private ArraySegment<byte> Encrypt(ArraySegment<byte> plaintext)
+        ArraySegment<byte> Encrypt(ArraySegment<byte> plaintext)
         {
             if (plaintext.Count == 0)
-            {
                 // Invalid
                 return new ArraySegment<byte>();
-            }
             // Need to make the nonce unique again before encrypting another message
             UpdateNonce();
             // Re-initialize the cipher with our cached parameters
-            Cipher.Init(true, _cipherParametersEncrypt);
+            Cipher.Value.Init(true, cipherParametersEncrypt);
 
             // Calculate the expected output size, this should always be input size + mac size
-            int outSize = Cipher.GetOutputSize(plaintext.Count);
+            int outSize = Cipher.Value.GetOutputSize(plaintext.Count);
 #if UNITY_EDITOR
             // expecting the outSize to be input size + MacSize
             if (outSize != plaintext.Count + MacSizeBytes)
-            {
                 throw new Exception($"Encrypt: Unexpected output size (Expected {plaintext.Count + MacSizeBytes}, got {outSize}");
-            }
 #endif
             // Resize the static buffer to fit
-            EnsureSize(ref _tmpCryptBuffer, outSize);
+            byte[] cryptBuffer = TMPCryptBuffer.Value;
+            EnsureSize(ref cryptBuffer, outSize);
+            TMPCryptBuffer.Value = cryptBuffer;
+            
             int resultLen;
             try
             {
                 // Run the plain text through the cipher, ProcessBytes will only process full blocks
                 resultLen =
-                    Cipher.ProcessBytes(plaintext.Array, plaintext.Offset, plaintext.Count, _tmpCryptBuffer, 0);
+                    Cipher.Value.ProcessBytes(plaintext.Array, plaintext.Offset, plaintext.Count, cryptBuffer, 0);
                 // Then run any potentially remaining partial blocks through with DoFinal (and calculate the mac)
-                resultLen += Cipher.DoFinal(_tmpCryptBuffer, resultLen);
+                resultLen += Cipher.Value.DoFinal(cryptBuffer, resultLen);
             }
             // catch all Exception's since BouncyCastle is fairly noisy with both standard and their own exception types
             //
             catch (Exception e)
             {
-                _error(TransportError.Unexpected, $"Unexpected exception while encrypting {e.GetType()}: {e.Message}");
+                error(TransportError.Unexpected, $"Unexpected exception while encrypting {e.GetType()}: {e.Message}");
                 return new ArraySegment<byte>();
             }
 #if UNITY_EDITOR
             // expecting the result length to match the previously calculated input size + MacSize
             if (resultLen != outSize)
-            {
                 throw new Exception($"Encrypt: resultLen did not match outSize (expected {outSize}, got {resultLen})");
-            }
 #endif
-            return new ArraySegment<byte>(_tmpCryptBuffer, 0, resultLen);
+            return new ArraySegment<byte>(cryptBuffer, 0, resultLen);
         }
 
-        private ArraySegment<byte> Decrypt(ArraySegment<byte> ciphertext)
+        ArraySegment<byte> Decrypt(ArraySegment<byte> ciphertext)
         {
             if (ciphertext.Count <= MacSizeBytes)
             {
-                _error(TransportError.Unexpected, $"Received too short data packet (min {{MacSizeBytes + 1}}, got {ciphertext.Count})");
+                error(TransportError.Unexpected, $"Received too short data packet (min {{MacSizeBytes + 1}}, got {ciphertext.Count})");
                 // Invalid
                 return new ArraySegment<byte>();
             }
             // Re-initialize the cipher with our cached parameters
-            Cipher.Init(false, _cipherParametersDecrypt);
+            Cipher.Value.Init(false, cipherParametersDecrypt);
 
             // Calculate the expected output size, this should always be input size - mac size
-            int outSize = Cipher.GetOutputSize(ciphertext.Count);
+            int outSize = Cipher.Value.GetOutputSize(ciphertext.Count);
 #if UNITY_EDITOR
             // expecting the outSize to be input size - MacSize
             if (outSize != ciphertext.Count - MacSizeBytes)
-            {
                 throw new Exception($"Decrypt: Unexpected output size (Expected {ciphertext.Count - MacSizeBytes}, got {outSize}");
-            }
 #endif
-            // Resize the static buffer to fit
-            EnsureSize(ref _tmpCryptBuffer, outSize);
+
+            byte[] cryptBuffer = TMPCryptBuffer.Value;
+            EnsureSize(ref cryptBuffer, outSize);
+            TMPCryptBuffer.Value = cryptBuffer;
+
             int resultLen;
             try
             {
                 // Run the ciphertext through the cipher, ProcessBytes will only process full blocks
                 resultLen =
-                    Cipher.ProcessBytes(ciphertext.Array, ciphertext.Offset, ciphertext.Count, _tmpCryptBuffer, 0);
+                    Cipher.Value.ProcessBytes(ciphertext.Array, ciphertext.Offset, ciphertext.Count, cryptBuffer, 0);
                 // Then run any potentially remaining partial blocks through with DoFinal (and calculate/check the mac)
-                resultLen += Cipher.DoFinal(_tmpCryptBuffer, resultLen);
+                resultLen += Cipher.Value.DoFinal(cryptBuffer, resultLen);
             }
             // catch all Exception's since BouncyCastle is fairly noisy with both standard and their own exception types
             catch (Exception e)
             {
-                _error(TransportError.Unexpected, $"Unexpected exception while decrypting {e.GetType()}: {e.Message}. This usually signifies corrupt data");
+                error(TransportError.Unexpected, $"Unexpected exception while decrypting {e.GetType()}: {e.Message}. This usually signifies corrupt data");
                 return new ArraySegment<byte>();
             }
 #if UNITY_EDITOR
             // expecting the result length to match the previously calculated input size + MacSize
             if (resultLen != outSize)
-            {
                 throw new Exception($"Decrypt: resultLen did not match outSize (expected {outSize}, got {resultLen})");
-            }
 #endif
-            return new ArraySegment<byte>(_tmpCryptBuffer, 0, resultLen);
+            return new ArraySegment<byte>(cryptBuffer, 0, resultLen);
         }
 
-        private void UpdateNonce()
+        void UpdateNonce()
         {
             // increment the nonce by one
             // we need to ensure the nonce is *always* unique and not reused
             // easiest way to do this is by simply incrementing it
             for (int i = 0; i < NonceSize; i++)
             {
-                _nonce[i]++;
-                if (_nonce[i] != 0)
-                {
+                nonce[i]++;
+                if (nonce[i] != 0)
                     break;
             }
         }
-        }
 
-        private static void EnsureSize(ref byte[] buffer, int size)
+        static void EnsureSize(ref byte[] buffer, int size)
         {
             if (buffer.Length < size)
-            {
                 // double buffer to avoid constantly resizing by a few bytes
                 Array.Resize(ref buffer, Math.Max(size, buffer.Length * 2));
         }
-        }
 
-        private void SendHandshakeAndPubKey(OpCodes opcode)
+        void SendHandshakeAndPubKey(OpCodes opcode)
         {
             using (NetworkWriterPooled writer = NetworkWriterPool.Get())
             {
                 writer.WriteByte((byte)opcode);
                 if (opcode == OpCodes.HandshakeAck)
-                {
-                    writer.WriteBytes(_hkdfSalt, 0, HkdfSaltSize);
-                }
-                writer.WriteBytes(_credentials.PublicKeySerialized, 0, _credentials.PublicKeySerialized.Length);
-                _send(writer.ToArraySegment(), Channels.Unreliable);
+                    writer.WriteBytes(hkdfSalt, 0, HkdfSaltSize);
+                writer.WriteBytes(credentials.PublicKeySerialized, 0, credentials.PublicKeySerialized.Length);
+                send(writer.ToArraySegment(), Channels.Unreliable);
             }
         }
 
-        private void SendHandshakeFin()
+        void SendHandshakeFin()
         {
             using (NetworkWriterPooled writer = NetworkWriterPool.Get())
             {
                 writer.WriteByte((byte)OpCodes.HandshakeFin);
-                _send(writer.ToArraySegment(), Channels.Unreliable);
+                send(writer.ToArraySegment(), Channels.Unreliable);
             }
         }
 
-        private void CompleteExchange(ArraySegment<byte> remotePubKeyRaw, byte[] salt)
+        void CompleteExchange(ArraySegment<byte> remotePubKeyRaw, byte[] salt)
         {
             AsymmetricKeyParameter remotePubKey;
             try
@@ -470,11 +441,11 @@ private void CompleteExchange(ArraySegment<byte> remotePubKeyRaw, byte[] salt)
             }
             catch (Exception e)
             {
-                _error(TransportError.Unexpected, $"Failed to deserialize public key of remote. {e.GetType()}: {e.Message}");
+                error(TransportError.Unexpected, $"Failed to deserialize public key of remote. {e.GetType()}: {e.Message}");
                 return;
             }
 
-            if (_validateRemoteKey != null)
+            if (validateRemoteKey != null)
             {
                 PubKeyInfo info = new PubKeyInfo
                 {
@@ -482,9 +453,9 @@ private void CompleteExchange(ArraySegment<byte> remotePubKeyRaw, byte[] salt)
                     Serialized = remotePubKeyRaw,
                     Key = remotePubKey
                 };
-                if (!_validateRemoteKey(info))
+                if (!validateRemoteKey(info))
                 {
-                    _error(TransportError.Unexpected, $"Remote public key (fingerprint: {info.Fingerprint}) failed validation. ");
+                    error(TransportError.Unexpected, $"Remote public key (fingerprint: {info.Fingerprint}) failed validation. ");
                     return;
                 }
             }
@@ -493,7 +464,7 @@ private void CompleteExchange(ArraySegment<byte> remotePubKeyRaw, byte[] salt)
             // This gives us the same key on the other side, with our public key and their remote
             // It's like magic, but with math!
             ECDHBasicAgreement ecdh = new ECDHBasicAgreement();
-            ecdh.Init(_credentials.PrivateKey);
+            ecdh.Init(credentials.PrivateKey);
             byte[] sharedSecret;
             try
             {
@@ -502,33 +473,33 @@ private void CompleteExchange(ArraySegment<byte> remotePubKeyRaw, byte[] salt)
             catch
                 (Exception e)
             {
-                _error(TransportError.Unexpected, $"Failed to calculate the ECDH key exchange. {e.GetType()}: {e.Message}");
+                error(TransportError.Unexpected, $"Failed to calculate the ECDH key exchange. {e.GetType()}: {e.Message}");
                 return;
             }
 
             if (salt.Length != HkdfSaltSize)
             {
-                _error(TransportError.Unexpected, $"Salt is expected to be {HkdfSaltSize} bytes long, got {salt.Length}.");
+                error(TransportError.Unexpected, $"Salt is expected to be {HkdfSaltSize} bytes long, got {salt.Length}.");
                 return;
             }
 
-            Hkdf.Init(new HkdfParameters(sharedSecret, salt, HkdfInfo));
+            Hkdf.Value.Init(new HkdfParameters(sharedSecret, salt, HkdfInfo));
 
             // Allocate a buffer for the output key
             byte[] keyRaw = new byte[KeyLength];
 
             // Generate the output keying material
-            Hkdf.GenerateBytes(keyRaw, 0, keyRaw.Length);
+            Hkdf.Value.GenerateBytes(keyRaw, 0, keyRaw.Length);
 
             KeyParameter key = new KeyParameter(keyRaw);
 
             // generate a starting nonce
-            _nonce = GenerateSecureBytes(NonceSize);
+            nonce = GenerateSecureBytes(NonceSize);
 
             // we pass in the nonce array once (as it's stored by reference) so we can cache the AeadParameters instance
             // instead of creating a new one each encrypt/decrypt
-            _cipherParametersEncrypt = new AeadParameters(key, MacSizeBits, _nonce);
-            _cipherParametersDecrypt = new AeadParameters(key, MacSizeBits, ReceiveNonce);
+            cipherParametersEncrypt = new AeadParameters(key, MacSizeBits, nonce);
+            cipherParametersDecrypt = new AeadParameters(key, MacSizeBits, ReceiveNonce.Value);
         }
 
         /**
@@ -537,53 +508,41 @@ private void CompleteExchange(ArraySegment<byte> remotePubKeyRaw, byte[] salt)
         public void TickNonReady(double time)
         {
             if (IsReady)
+                return;
+
+            // Timeout reset
+            if (handshakeTimeout == 0)
+                handshakeTimeout = time + DurationTimeout;
+            else if (time > handshakeTimeout)
             {
+                error?.Invoke(TransportError.Timeout, $"Timed out during {state}, this probably just means the other side went away which is fine.");
                 return;
             }
 
             // Timeout reset
-            if (_handshakeTimeout == 0)
+            if (nextHandshakeResend < 0)
             {
-                _handshakeTimeout = time + DurationTimeout;
-            }
-            else if (time > _handshakeTimeout)
-            {
-                _error?.Invoke(TransportError.Timeout, $"Timed out during {_state}, this probably just means the other side went away which is fine.");
+                nextHandshakeResend = time + DurationResend;
                 return;
             }
 
-            // Timeout reset
-            if (_nextHandshakeResend < 0)
-            {
-                _nextHandshakeResend = time + DurationResend;
-                return;
-            }
-
-            if (time < _nextHandshakeResend)
-            {
+            if (time < nextHandshakeResend)
                 // Resend isn't due yet
                 return;
-            }
 
-            _nextHandshakeResend = time + DurationResend;
-            switch (_state)
+            nextHandshakeResend = time + DurationResend;
+            switch (state)
             {
                 case State.WaitingHandshake:
-                    if (_sendsFirst)
-                    {
+                    if (sendsFirst)
                         SendHandshakeAndPubKey(OpCodes.HandshakeStart);
-                    }
 
                     break;
                 case State.WaitingHandshakeReply:
-                    if (_sendsFirst)
-                    {
+                    if (sendsFirst)
                         SendHandshakeFin();
-                    }
                     else
-                    {
                         SendHandshakeAndPubKey(OpCodes.HandshakeAck);
-                    }
 
                     break;
                 case State.Ready: // IsReady is checked above & early-returned

Assets/Mirror/Transports/Encryption/EncryptionCredentials.cs

@@ -51,13 +51,11 @@ public static byte[] SerializePublicKey(AsymmetricKeyParameter publicKey)
             return publicKeyInfo.ToAsn1Object().GetDerEncoded();
         }
 
-        public static AsymmetricKeyParameter DeserializePublicKey(ArraySegment<byte> pubKey)
-        {
+        public static AsymmetricKeyParameter DeserializePublicKey(ArraySegment<byte> pubKey) =>
             // And then we do this to deserialize from the DER (from above)
             // the "new MemoryStream" actually saves an allocation, since otherwise the ArraySegment would be converted
             // to a byte[] first and then shoved through a MemoryStream
-            return PublicKeyFactory.CreateKey(new MemoryStream(pubKey.Array, pubKey.Offset, pubKey.Count, false));
-        }
+            PublicKeyFactory.CreateKey(new MemoryStream(pubKey.Array, pubKey.Offset, pubKey.Count, false));
 
         public static byte[] SerializePrivateKey(AsymmetricKeyParameter privateKey)
         {
@@ -66,13 +64,11 @@ public static byte[] SerializePrivateKey(AsymmetricKeyParameter privateKey)
             return privateKeyInfo.ToAsn1Object().GetDerEncoded();
         }
 
-        public static AsymmetricKeyParameter DeserializePrivateKey(ArraySegment<byte> privateKey)
-        {
+        public static AsymmetricKeyParameter DeserializePrivateKey(ArraySegment<byte> privateKey) =>
             // And then we do this to deserialize from the DER (from above)
             // the "new MemoryStream" actually saves an allocation, since otherwise the ArraySegment would be converted
             // to a byte[] first and then shoved through a MemoryStream
-            return PrivateKeyFactory.CreateKey(new MemoryStream(privateKey.Array, privateKey.Offset, privateKey.Count, false));
-        }
+            PrivateKeyFactory.CreateKey(new MemoryStream(privateKey.Array, privateKey.Offset, privateKey.Count, false));
 
         public static string PubKeyFingerprint(ArraySegment<byte> publicKeyBytes)
         {
@@ -90,7 +86,7 @@ public void SaveToFile(string path)
             {
                 PublicKeyFingerprint = PublicKeyFingerprint,
                 PublicKey = Convert.ToBase64String(PublicKeySerialized),
-                PrivateKey= Convert.ToBase64String(SerializePrivateKey(PrivateKey)),
+                PrivateKey= Convert.ToBase64String(SerializePrivateKey(PrivateKey))
             });
             File.WriteAllText(path, json);
         }
@@ -104,9 +100,7 @@ public static EncryptionCredentials LoadFromFile(string path)
             byte[] privateKeyBytes = Convert.FromBase64String(serializedPair.PrivateKey);
 
             if (serializedPair.PublicKeyFingerprint != PubKeyFingerprint(new ArraySegment<byte>(publicKeyBytes)))
-            {
                 throw new Exception("Saved public key fingerprint does not match public key.");
-            }
             return new EncryptionCredentials
             {
                 PublicKeySerialized = publicKeyBytes,
@@ -115,7 +109,7 @@ public static EncryptionCredentials LoadFromFile(string path)
             };
         }
 
-        private class SerializedPair
+        class SerializedPair
         {
             public string PublicKeyFingerprint;
             public string PublicKey;

Assets/Mirror/Transports/Encryption/EncryptionTransport.cs

@@ -12,28 +12,27 @@ public class EncryptionTransport : Transport, PortTransport
     {
         public override bool IsEncrypted => true;
         public override string EncryptionCipher => "AES256-GCM";
-        public Transport inner;
+        [FormerlySerializedAs("inner")]
+        public Transport Inner;
 
         public ushort Port
         {
             get
             {
-                if (inner is PortTransport portTransport)
-                {
+                if (Inner is PortTransport portTransport)
                     return portTransport.Port;
-                }
 
-                Debug.LogError($"EncryptionTransport can't get Port because {inner} is not a PortTransport");
+                Debug.LogError($"EncryptionTransport can't get Port because {Inner} is not a PortTransport");
                 return 0;
             }
             set
             {
-                if (inner is PortTransport portTransport)
+                if (Inner is PortTransport portTransport)
                 {
                     portTransport.Port = value;
                     return;
                 }
-                Debug.LogError($"EncryptionTransport can't set Port because {inner} is not a PortTransport");
+                Debug.LogError($"EncryptionTransport can't set Port because {Inner} is not a PortTransport");
             }
         }
 
@@ -41,81 +40,78 @@ public enum ValidationMode
         {
             Off,
             List,
-            Callback,
+            Callback
         }
 
-        public ValidationMode clientValidateServerPubKey;
+        [FormerlySerializedAs("clientValidateServerPubKey")]
+        public ValidationMode ClientValidateServerPubKey;
+        [FormerlySerializedAs("clientTrustedPubKeySignatures")]
         [Tooltip("List of public key fingerprints the client will accept")]
-        public string[] clientTrustedPubKeySignatures;
-        public Func<PubKeyInfo, bool> onClientValidateServerPubKey;
-        public bool serverLoadKeyPairFromFile;
-        public string serverKeypairPath = "./server-keys.json";
+        public string[] ClientTrustedPubKeySignatures;
+        public Func<PubKeyInfo, bool> OnClientValidateServerPubKey;
+        [FormerlySerializedAs("serverLoadKeyPairFromFile")]
+        public bool ServerLoadKeyPairFromFile;
+        [FormerlySerializedAs("serverKeypairPath")]
+        public string ServerKeypairPath = "./server-keys.json";
 
-        private EncryptedConnection _client;
+        EncryptedConnection client;
 
-        private Dictionary<int, EncryptedConnection> _serverConnections = new Dictionary<int, EncryptedConnection>();
+        readonly Dictionary<int, EncryptedConnection> serverConnections = new Dictionary<int, EncryptedConnection>();
 
-        private List<EncryptedConnection> _serverPendingConnections =
+        readonly List<EncryptedConnection> serverPendingConnections =
             new List<EncryptedConnection>();
 
-        private EncryptionCredentials _credentials;
-        public string EncryptionPublicKeyFingerprint => _credentials?.PublicKeyFingerprint;
-        public byte[] EncryptionPublicKey => _credentials?.PublicKeySerialized;
+        EncryptionCredentials credentials;
+        public string EncryptionPublicKeyFingerprint => credentials?.PublicKeyFingerprint;
+        public byte[] EncryptionPublicKey => credentials?.PublicKeySerialized;
 
-        private void ServerRemoveFromPending(EncryptedConnection con)
+        void ServerRemoveFromPending(EncryptedConnection con)
         {
-            for (int i = 0; i < _serverPendingConnections.Count; i++)
-            {
-                if (_serverPendingConnections[i] == con)
+            for (int i = 0; i < serverPendingConnections.Count; i++)
+                if (serverPendingConnections[i] == con)
                 {
                     // remove by swapping with last
-                    int lastIndex = _serverPendingConnections.Count - 1;
-                    _serverPendingConnections[i] = _serverPendingConnections[lastIndex];
-                    _serverPendingConnections.RemoveAt(lastIndex);
+                    int lastIndex = serverPendingConnections.Count - 1;
+                    serverPendingConnections[i] = serverPendingConnections[lastIndex];
+                    serverPendingConnections.RemoveAt(lastIndex);
                     break;
                 }
         }
-        }
 
-        private void HandleInnerServerDisconnected(int connId)
+        void HandleInnerServerDisconnected(int connId)
         {
-            if (_serverConnections.TryGetValue(connId, out EncryptedConnection con))
+            if (serverConnections.TryGetValue(connId, out EncryptedConnection con))
             {
                 ServerRemoveFromPending(con);
-                _serverConnections.Remove(connId);
+                serverConnections.Remove(connId);
             }
             OnServerDisconnected?.Invoke(connId);
         }
 
-        private void HandleInnerServerError(int connId, TransportError type, string msg)
-        {
-            OnServerError?.Invoke(connId, type, $"inner: {msg}");
-        }
+        void HandleInnerServerError(int connId, TransportError type, string msg) => OnServerError?.Invoke(connId, type, $"inner: {msg}");
 
-        private void HandleInnerServerDataReceived(int connId, ArraySegment<byte> data, int channel)
-        {
-            if (_serverConnections.TryGetValue(connId, out EncryptedConnection c))
+        void HandleInnerServerDataReceived(int connId, ArraySegment<byte> data, int channel)
         {
+            if (serverConnections.TryGetValue(connId, out EncryptedConnection c))
                 c.OnReceiveRaw(data, channel);
         }
-        }
 
-        private void HandleInnerServerConnected(int connId) => HandleInnerServerConnected(connId, inner.ServerGetClientAddress(connId));
+        void HandleInnerServerConnected(int connId) => HandleInnerServerConnected(connId, Inner.ServerGetClientAddress(connId));
 
-        private void HandleInnerServerConnected(int connId, string clientRemoteAddress)
+        void HandleInnerServerConnected(int connId, string clientRemoteAddress)
         {
-            Debug.Log($"[EncryptionTransport] New connection #{connId}");
+            Debug.Log($"[EncryptionTransport] New connection #{connId} from {clientRemoteAddress}");
             EncryptedConnection ec = null;
             ec = new EncryptedConnection(
-                _credentials,
+                credentials,
                 false,
-                (segment, channel) => inner.ServerSend(connId, segment, channel),
+                (segment, channel) => Inner.ServerSend(connId, segment, channel),
                 (segment, channel) => OnServerDataReceived?.Invoke(connId, segment, channel),
                 () =>
                 {
                     Debug.Log($"[EncryptionTransport] Connection #{connId} is ready");
+                    // ReSharper disable once AccessToModifiedClosure
                     ServerRemoveFromPending(ec);
-                    //OnServerConnected?.Invoke(connId);
                     OnServerConnectedWithAddress?.Invoke(connId, clientRemoteAddress);
                 },
                 (type, msg) =>
@@ -123,32 +119,25 @@ private void HandleInnerServerConnected(int connId, string clientRemoteAddress)
                     OnServerError?.Invoke(connId, type, msg);
                     ServerDisconnect(connId);
                 });
-            _serverConnections.Add(connId, ec);
-            _serverPendingConnections.Add(ec);
+            serverConnections.Add(connId, ec);
+            serverPendingConnections.Add(ec);
         }
 
-        private void HandleInnerClientDisconnected()
+        void HandleInnerClientDisconnected()
         {
-            _client = null;
+            client = null;
             OnClientDisconnected?.Invoke();
         }
 
-        private void HandleInnerClientError(TransportError arg1, string arg2)
-        {
-            OnClientError?.Invoke(arg1, $"inner: {arg2}");
-        }
+        void HandleInnerClientError(TransportError arg1, string arg2) => OnClientError?.Invoke(arg1, $"inner: {arg2}");
 
-        private void HandleInnerClientDataReceived(ArraySegment<byte> data, int channel)
-        {
-            _client?.OnReceiveRaw(data, channel);
-        }
+        void HandleInnerClientDataReceived(ArraySegment<byte> data, int channel) => client?.OnReceiveRaw(data, channel);
 
-        private void HandleInnerClientConnected()
-        {
-            _client = new EncryptedConnection(
-                _credentials,
+        void HandleInnerClientConnected() =>
+            client = new EncryptedConnection(
+                credentials,
                 true,
-                (segment, channel) => inner.ClientSend(segment, channel),
+                (segment, channel) => Inner.ClientSend(segment, channel),
                 (segment, channel) => OnClientDataReceived?.Invoke(segment, channel),
                 () =>
                 {
@@ -160,25 +149,23 @@ private void HandleInnerClientConnected()
                     ClientDisconnect();
                 },
                 HandleClientValidateServerPubKey);
-        }
 
-        private bool HandleClientValidateServerPubKey(PubKeyInfo pubKeyInfo)
+        bool HandleClientValidateServerPubKey(PubKeyInfo pubKeyInfo)
         {
-            switch (clientValidateServerPubKey)
+            switch (ClientValidateServerPubKey)
             {
                 case ValidationMode.Off:
                     return true;
                 case ValidationMode.List:
-                    return Array.IndexOf(clientTrustedPubKeySignatures, pubKeyInfo.Fingerprint) >= 0;
+                    return Array.IndexOf(ClientTrustedPubKeySignatures, pubKeyInfo.Fingerprint) >= 0;
                 case ValidationMode.Callback:
-                    return onClientValidateServerPubKey(pubKeyInfo);
+                    return OnClientValidateServerPubKey(pubKeyInfo);
                 default:
                     throw new ArgumentOutOfRangeException();
             }
         }
 
-        void Awake()
-        {
+        void Awake() =>
             // check if encryption via hardware acceleration is supported.
             // this can be useful to know for low end devices.
             //
@@ -188,27 +175,26 @@ void Awake()
             //   https://github.com/bcgit/bc-csharp/blob/449940429c57686a6fcf6bfbb4d368dec19d906e/crypto/src/crypto/engines/AesEngine_X86.cs
             // which Unity does not support yet.
             Debug.Log($"EncryptionTransport: IsHardwareAccelerated={AesUtilities.IsHardwareAccelerated}");
-        }
 
-        public override bool Available() => inner.Available();
+        public override bool Available() => Inner.Available();
 
-        public override bool ClientConnected() => _client != null && _client.IsReady;
+        public override bool ClientConnected() => client != null && client.IsReady;
 
         public override void ClientConnect(string address)
         {
-            switch (clientValidateServerPubKey)
+            switch (ClientValidateServerPubKey)
             {
                 case ValidationMode.Off:
                     break;
                 case ValidationMode.List:
-                    if (clientTrustedPubKeySignatures == null || clientTrustedPubKeySignatures.Length == 0)
+                    if (ClientTrustedPubKeySignatures == null || ClientTrustedPubKeySignatures.Length == 0)
                     {
                         OnClientError?.Invoke(TransportError.Unexpected, "Validate Server Public Key is set to List, but the clientTrustedPubKeySignatures list is empty.");
                         return;
                     }
                     break;
                 case ValidationMode.Callback:
-                    if (onClientValidateServerPubKey == null)
+                    if (OnClientValidateServerPubKey == null)
                     {
                         OnClientError?.Invoke(TransportError.Unexpected, "Validate Server Public Key is set to Callback, but the onClientValidateServerPubKey handler is not set");
                         return;
@@ -217,95 +203,79 @@ public override void ClientConnect(string address)
                 default:
                     throw new ArgumentOutOfRangeException();
             }
-            _credentials = EncryptionCredentials.Generate();
-            inner.OnClientConnected = HandleInnerClientConnected;
-            inner.OnClientDataReceived = HandleInnerClientDataReceived;
-            inner.OnClientDataSent = (bytes, channel) => OnClientDataSent?.Invoke(bytes, channel);
-            inner.OnClientError = HandleInnerClientError;
-            inner.OnClientDisconnected = HandleInnerClientDisconnected;
-            inner.ClientConnect(address);
+            credentials = EncryptionCredentials.Generate();
+            Inner.OnClientConnected = HandleInnerClientConnected;
+            Inner.OnClientDataReceived = HandleInnerClientDataReceived;
+            Inner.OnClientDataSent = (bytes, channel) => OnClientDataSent?.Invoke(bytes, channel);
+            Inner.OnClientError = HandleInnerClientError;
+            Inner.OnClientDisconnected = HandleInnerClientDisconnected;
+            Inner.ClientConnect(address);
         }
 
         public override void ClientSend(ArraySegment<byte> segment, int channelId = Channels.Reliable) =>
-            _client?.Send(segment, channelId);
+            client?.Send(segment, channelId);
 
-        public override void ClientDisconnect() => inner.ClientDisconnect();
+        public override void ClientDisconnect() => Inner.ClientDisconnect();
 
-        public override Uri ServerUri() => inner.ServerUri();
+        public override Uri ServerUri() => Inner.ServerUri();
 
-        public override bool ServerActive() => inner.ServerActive();
+        public override bool ServerActive() => Inner.ServerActive();
 
         public override void ServerStart()
         {
-            if (serverLoadKeyPairFromFile)
-            {
-                _credentials = EncryptionCredentials.LoadFromFile(serverKeypairPath);
-            }
+            if (ServerLoadKeyPairFromFile)
+                credentials = EncryptionCredentials.LoadFromFile(ServerKeypairPath);
             else
-            {
-                _credentials = EncryptionCredentials.Generate();
-            }
+                credentials = EncryptionCredentials.Generate();
 #pragma warning disable CS0618 // Type or member is obsolete
-            inner.OnServerConnected = HandleInnerServerConnected;
+            Inner.OnServerConnected = HandleInnerServerConnected;
 #pragma warning restore CS0618 // Type or member is obsolete
-            inner.OnServerConnectedWithAddress = HandleInnerServerConnected;
-            inner.OnServerDataReceived = HandleInnerServerDataReceived;
-            inner.OnServerDataSent = (connId, bytes, channel) => OnServerDataSent?.Invoke(connId, bytes, channel);
-            inner.OnServerError = HandleInnerServerError;
-            inner.OnServerDisconnected = HandleInnerServerDisconnected;
-            inner.ServerStart();
+            Inner.OnServerConnectedWithAddress = HandleInnerServerConnected;
+            Inner.OnServerDataReceived = HandleInnerServerDataReceived;
+            Inner.OnServerDataSent = (connId, bytes, channel) => OnServerDataSent?.Invoke(connId, bytes, channel);
+            Inner.OnServerError = HandleInnerServerError;
+            Inner.OnServerDisconnected = HandleInnerServerDisconnected;
+            Inner.ServerStart();
         }
 
         public override void ServerSend(int connectionId, ArraySegment<byte> segment, int channelId = Channels.Reliable)
         {
-            if (_serverConnections.TryGetValue(connectionId, out EncryptedConnection connection) && connection.IsReady)
-            {
+            if (serverConnections.TryGetValue(connectionId, out EncryptedConnection connection) && connection.IsReady)
                 connection.Send(segment, channelId);
         }
-        }
 
-        public override void ServerDisconnect(int connectionId)
-        {
+        public override void ServerDisconnect(int connectionId) =>
             // cleanup is done via inners disconnect event
-            inner.ServerDisconnect(connectionId);
-        }
+            Inner.ServerDisconnect(connectionId);
 
-        public override string ServerGetClientAddress(int connectionId) => inner.ServerGetClientAddress(connectionId);
+        public override string ServerGetClientAddress(int connectionId) => Inner.ServerGetClientAddress(connectionId);
 
-        public override void ServerStop() => inner.ServerStop();
+        public override void ServerStop() => Inner.ServerStop();
 
         public override int GetMaxPacketSize(int channelId = Channels.Reliable) =>
-            inner.GetMaxPacketSize(channelId) - EncryptedConnection.Overhead;
+            Inner.GetMaxPacketSize(channelId) - EncryptedConnection.Overhead;
 
-        public override void Shutdown() => inner.Shutdown();
+        public override void Shutdown() => Inner.Shutdown();
 
-        public override void ClientEarlyUpdate()
-        {
-            inner.ClientEarlyUpdate();
-        }
+        public override void ClientEarlyUpdate() => Inner.ClientEarlyUpdate();
 
         public override void ClientLateUpdate()
         {
-            inner.ClientLateUpdate();
+            Inner.ClientLateUpdate();
             Profiler.BeginSample("EncryptionTransport.ServerLateUpdate");
-            _client?.TickNonReady(NetworkTime.localTime);
+            client?.TickNonReady(NetworkTime.localTime);
             Profiler.EndSample();
         }
 
-        public override void ServerEarlyUpdate()
-        {
-            inner.ServerEarlyUpdate();
-        }
+        public override void ServerEarlyUpdate() => Inner.ServerEarlyUpdate();
 
         public override void ServerLateUpdate()
         {
-            inner.ServerLateUpdate();
+            Inner.ServerLateUpdate();
             Profiler.BeginSample("EncryptionTransport.ServerLateUpdate");
             // Reverse iteration as entries can be removed while updating
-            for (int i = _serverPendingConnections.Count - 1; i >= 0; i--)
-            {
-                _serverPendingConnections[i].TickNonReady(NetworkTime.time);
-            }
+            for (int i = serverPendingConnections.Count - 1; i >= 0; i--)
+                serverPendingConnections[i].TickNonReady(NetworkTime.time);
             Profiler.EndSample();
         }
     }

Assets/Mirror/Transports/Encryption/ThreadedEncryptionTransport.cs

@@ -0,0 +1,314 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Net;
+using Mirror.BouncyCastle.Crypto;
+using UnityEngine;
+using UnityEngine.Profiling;
+using UnityEngine.Serialization;
+using Debug = UnityEngine.Debug;
+
+namespace Mirror.Transports.Encryption
+{
+    [HelpURL("https://mirror-networking.gitbook.io/docs/manual/transports/encryption-transport")]
+    public class ThreadedEncryptionTransport : ThreadedTransport, PortTransport
+    {
+        public override bool IsEncrypted => true;
+        public override string EncryptionCipher => "AES256-GCM";
+        [FormerlySerializedAs("inner")]
+        public ThreadedTransport Inner;
+
+        public ushort Port
+        {
+            get
+            {
+                if (Inner is PortTransport portTransport)
+                    return portTransport.Port;
+
+                Debug.LogError($"ThreadedEncryptionTransport can't get Port because {Inner} is not a PortTransport");
+                return 0;
+            }
+            set
+            {
+                if (Inner is PortTransport portTransport)
+                {
+                    portTransport.Port = value;
+                    return;
+                }
+                Debug.LogError($"ThreadedEncryptionTransport can't set Port because {Inner} is not a PortTransport");
+            }
+        }
+
+        public enum ValidationMode
+        {
+            Off,
+            List,
+            Callback
+        }
+
+        [FormerlySerializedAs("clientValidateServerPubKey")]
+        public ValidationMode ClientValidateServerPubKey;
+        [FormerlySerializedAs("clientTrustedPubKeySignatures")]
+        [Tooltip("List of public key fingerprints the client will accept")]
+        public string[] ClientTrustedPubKeySignatures;
+        /// <summary>
+        /// Called when a client connects to a server
+        /// ATTENTION: NOT THREAD SAFE.
+        /// This will be called on the worker thread.
+        /// </summary>
+        public Func<PubKeyInfo, bool> OnClientValidateServerPubKey;
+        [FormerlySerializedAs("serverLoadKeyPairFromFile")]
+        public bool ServerLoadKeyPairFromFile;
+        [FormerlySerializedAs("serverKeypairPath")]
+        public string ServerKeypairPath = "./server-keys.json";
+
+        EncryptedConnection client;
+
+        readonly Dictionary<int, EncryptedConnection> serverConnections = new Dictionary<int, EncryptedConnection>();
+
+        readonly List<EncryptedConnection> serverPendingConnections =
+            new List<EncryptedConnection>();
+
+        EncryptionCredentials credentials;
+        public string EncryptionPublicKeyFingerprint => credentials?.PublicKeyFingerprint;
+        public byte[] EncryptionPublicKey => credentials?.PublicKeySerialized;
+
+        // Used for threaded time keeping as unitys Time.time is not thread safe
+        Stopwatch stopwatch = Stopwatch.StartNew();
+
+        void ServerRemoveFromPending(EncryptedConnection con)
+        {
+            for (int i = 0; i < serverPendingConnections.Count; i++)
+                if (serverPendingConnections[i] == con)
+                {
+                    // remove by swapping with last
+                    int lastIndex = serverPendingConnections.Count - 1;
+                    serverPendingConnections[i] = serverPendingConnections[lastIndex];
+                    serverPendingConnections.RemoveAt(lastIndex);
+                    break;
+                }
+        }
+
+        void HandleInnerServerDisconnected(int connId)
+        {
+            if (serverConnections.TryGetValue(connId, out EncryptedConnection con))
+            {
+                ServerRemoveFromPending(con);
+                serverConnections.Remove(connId);
+            }
+            OnThreadedServerDisconnected(connId);
+        }
+
+        void HandleInnerServerError(int connId, TransportError type, string msg) => OnThreadedServerError(connId, type, $"inner: {msg}");
+
+        void HandleInnerServerDataReceived(int connId, ArraySegment<byte> data, int channel)
+        {
+            if (serverConnections.TryGetValue(connId, out EncryptedConnection c))
+                c.OnReceiveRaw(data, channel);
+        }
+
+        void HandleInnerServerConnected(int connId) => HandleInnerServerConnected(connId, Inner.ServerGetClientAddress(connId));
+
+        void HandleInnerServerConnected(int connId, string clientRemoteAddress)
+        {
+            Debug.Log($"[ThreadedEncryptionTransport] New connection #{connId} from {clientRemoteAddress}");
+            EncryptedConnection ec = null;
+            ec = new EncryptedConnection(
+                credentials,
+                false,
+                (segment, channel) => Inner.ServerSend(connId, segment, channel),
+                (segment, channel) => OnThreadedServerReceive(connId, segment, channel),
+                () =>
+                {
+                    Debug.Log($"[ThreadedEncryptionTransport] Connection #{connId} is ready");
+                    // ReSharper disable once AccessToModifiedClosure
+                    ServerRemoveFromPending(ec);
+                    OnThreadedServerConnected(connId, new IPEndPoint(IPAddress.Parse(clientRemoteAddress), 0));
+                },
+                (type, msg) =>
+                {
+                    OnThreadedServerError(connId, type, msg);
+                    ServerDisconnect(connId);
+                });
+            serverConnections.Add(connId, ec);
+            serverPendingConnections.Add(ec);
+        }
+
+        void HandleInnerClientDisconnected()
+        {
+            client = null;
+            OnThreadedClientDisconnected();
+        }
+
+        void HandleInnerClientError(TransportError arg1, string arg2) => OnThreadedClientError(arg1, $"inner: {arg2}");
+
+        void HandleInnerClientDataReceived(ArraySegment<byte> data, int channel) => client?.OnReceiveRaw(data, channel);
+
+        void HandleInnerClientConnected() =>
+            client = new EncryptedConnection(
+                credentials,
+                true,
+                (segment, channel) => Inner.ClientSend(segment, channel),
+                (segment, channel) => OnThreadedClientReceive(segment, channel),
+                () =>
+                {
+                    OnThreadedClientConnected();
+                },
+                (type, msg) =>
+                {
+                    OnThreadedClientError(type, msg);
+                    ClientDisconnect();
+                },
+                HandleClientValidateServerPubKey);
+
+        bool HandleClientValidateServerPubKey(PubKeyInfo pubKeyInfo)
+        {
+            switch (ClientValidateServerPubKey)
+            {
+                case ValidationMode.Off:
+                    return true;
+                case ValidationMode.List:
+                    return Array.IndexOf(ClientTrustedPubKeySignatures, pubKeyInfo.Fingerprint) >= 0;
+                case ValidationMode.Callback:
+                    return OnClientValidateServerPubKey(pubKeyInfo);
+                default:
+                    throw new ArgumentOutOfRangeException();
+            }
+        }
+
+        protected override void Awake()
+        {
+            base.Awake();
+            // check if encryption via hardware acceleration is supported.
+            // this can be useful to know for low end devices.
+            //
+            // hardware acceleration requires netcoreapp3.0 or later:
+            //   https://github.com/bcgit/bc-csharp/blob/449940429c57686a6fcf6bfbb4d368dec19d906e/crypto/src/crypto/AesUtilities.cs#L18
+            // because AesEngine_x86 requires System.Runtime.Intrinsics.X86:
+            //   https://github.com/bcgit/bc-csharp/blob/449940429c57686a6fcf6bfbb4d368dec19d906e/crypto/src/crypto/engines/AesEngine_X86.cs
+            // which Unity does not support yet.
+            Debug.Log($"ThreadedEncryptionTransport: IsHardwareAccelerated={AesUtilities.IsHardwareAccelerated}");
+        }
+
+        public override bool Available() => Inner.Available();
+
+        protected override void ThreadedClientConnect(string address)
+        {
+            switch (ClientValidateServerPubKey)
+            {
+                case ValidationMode.Off:
+                    break;
+                case ValidationMode.List:
+                    if (ClientTrustedPubKeySignatures == null || ClientTrustedPubKeySignatures.Length == 0)
+                    {
+                        OnThreadedClientError(TransportError.Unexpected, "Validate Server Public Key is set to List, but the clientTrustedPubKeySignatures list is empty.");
+                        return;
+                    }
+                    break;
+                case ValidationMode.Callback:
+                    if (OnClientValidateServerPubKey == null)
+                    {
+                        OnThreadedClientError(TransportError.Unexpected, "Validate Server Public Key is set to Callback, but the onClientValidateServerPubKey handler is not set");
+                        return;
+                    }
+                    break;
+                default:
+                    throw new ArgumentOutOfRangeException();
+            }
+            credentials = EncryptionCredentials.Generate();
+            Inner.OnClientConnected = HandleInnerClientConnected;
+            Inner.OnClientDataReceived = HandleInnerClientDataReceived;
+            Inner.OnClientDataSent = (bytes, channel) => OnThreadedClientSend(bytes, channel);
+            Inner.OnClientError = HandleInnerClientError;
+            Inner.OnClientDisconnected = HandleInnerClientDisconnected;
+            Inner.ClientConnect(address);
+        }
+
+        protected override void ThreadedClientConnect(Uri address) => Inner.ClientConnect(address);
+
+        protected override void ThreadedClientSend(ArraySegment<byte> segment, int channelId) =>
+            client?.Send(segment, channelId);
+
+        protected override void ThreadedClientDisconnect() => Inner.ClientDisconnect();
+
+        protected override void ThreadedServerStart()
+        {
+            if (ServerLoadKeyPairFromFile)
+                credentials = EncryptionCredentials.LoadFromFile(ServerKeypairPath);
+            else
+                credentials = EncryptionCredentials.Generate();
+#pragma warning disable CS0618 // Type or member is obsolete
+            Inner.OnServerConnected = HandleInnerServerConnected;
+#pragma warning restore CS0618 // Type or member is obsolete
+            Inner.OnServerConnectedWithAddress = HandleInnerServerConnected;
+            Inner.OnServerDataReceived = HandleInnerServerDataReceived;
+            Inner.OnServerDataSent = (connId, bytes, channel) => OnThreadedServerSend(connId, bytes, channel);
+            Inner.OnServerError = HandleInnerServerError;
+            Inner.OnServerDisconnected = HandleInnerServerDisconnected;
+            Inner.ServerStart();
+        }
+
+        protected override void ThreadedServerSend(int connectionId, ArraySegment<byte> segment, int channelId)
+        {
+            if (serverConnections.TryGetValue(connectionId, out EncryptedConnection connection) && connection.IsReady)
+                connection.Send(segment, channelId);
+        }
+
+        protected override void ThreadedServerDisconnect(int connectionId) =>
+            // cleanup is done via inners disconnect event
+            Inner.ServerDisconnect(connectionId);
+
+        protected override void ThreadedClientEarlyUpdate() {}
+
+        protected override void ThreadedServerStop() => Inner.ServerStop();
+
+        public override Uri ServerUri() => Inner.ServerUri();
+
+        public override int GetMaxPacketSize(int channelId = Channels.Reliable) =>
+            Inner.GetMaxPacketSize(channelId) - EncryptedConnection.Overhead;
+
+        protected override void ThreadedShutdown() => Inner.Shutdown();
+
+        public override void ClientEarlyUpdate()
+        {
+            base.ClientEarlyUpdate();
+            Inner.ClientEarlyUpdate();
+        }
+
+        public override void ClientLateUpdate()
+        {
+            base.ClientLateUpdate();
+            Inner.ClientLateUpdate();
+        }
+
+        protected override void ThreadedClientLateUpdate()
+        {
+            Profiler.BeginSample("ThreadedEncryptionTransport.ServerLateUpdate");
+            client?.TickNonReady(stopwatch.Elapsed.TotalSeconds);
+            Profiler.EndSample();
+        }
+
+        protected override void ThreadedServerEarlyUpdate() {}
+
+        public override void ServerEarlyUpdate()
+        {
+            base.ServerEarlyUpdate();
+            Inner.ServerEarlyUpdate();
+        }
+
+        public override void ServerLateUpdate()
+        {
+            base.ServerLateUpdate();
+            Inner.ServerLateUpdate();
+        }
+
+        protected override void ThreadedServerLateUpdate()
+        {
+            Profiler.BeginSample("ThreadedEncryptionTransport.ServerLateUpdate");
+            // Reverse iteration as entries can be removed while updating
+            for (int i = serverPendingConnections.Count - 1; i >= 0; i--)
+                serverPendingConnections[i].TickNonReady(stopwatch.Elapsed.TotalSeconds);
+            Profiler.EndSample();
+        }
+    }
+}

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