Protocol: call the encryptor once before sending data

src/ClientHandle.cpp

@@ -238,6 +238,7 @@ void cClientHandle::ProcessProtocolOut()
 	// to prevent it being reset between the null check and the Send:
 	if (auto Link = m_Link; Link != nullptr)
 	{
+		m_Protocol->DataPrepared(OutgoingData);
 		Link->Send(OutgoingData.data(), OutgoingData.size());
 	}
 }

src/Protocol/Protocol.h

@@ -346,10 +346,15 @@ public:
 		Game = 3,
 	};
 
-	/** Called to process them, when client sends some data.
+	/** Called by cClientHandle to process data, when the client sends some.
 	The protocol uses the provided buffers for storage and processing, and must have exclusive access to them. */
 	virtual void DataReceived(cByteBuffer & a_Buffer, ContiguousByteBuffer && a_Data) = 0;
 
+	/** Called by cClientHandle to finalise a buffer of prepared data before they are sent to the client.
+	Descendants may for example, encrypt the data if needed.
+	The protocol modifies the provided buffer in-place. */
+	virtual void DataPrepared(ContiguousByteBuffer & a_Data) = 0;
+
 	// Sending stuff to clients (alphabetically sorted):
 	virtual void SendAttachEntity               (const cEntity & a_Entity, const cEntity & a_Vehicle) = 0;
 	virtual void SendBlockAction                (int a_BlockX, int a_BlockY, int a_BlockZ, char a_Byte1, char a_Byte2, BLOCKTYPE a_BlockType) = 0;
@@ -466,9 +471,6 @@ protected:
 	/** Returns the current protocol's version, for handling status requests. */
 	virtual Version GetProtocolVersion() const = 0;
 
-	/** A generic data-sending routine, all outgoing packet data needs to be routed through this so that descendants may override it. */
-	virtual void SendData(ContiguousByteBufferView a_Data) = 0;
-
 	/** Sends a single packet contained within the cPacketizer class.
 	The cPacketizer's destructor calls this to send the contained packet; protocol may transform the data (compression in 1.8 etc). */
 	virtual void SendPacket(cPacketizer & a_Packet) = 0;

src/Protocol/Protocol_1_8.cpp

@@ -188,6 +188,18 @@ void cProtocol_1_8_0::DataReceived(cByteBuffer & a_Buffer, ContiguousByteBuffer
 
 
 
+void cProtocol_1_8_0::DataPrepared(ContiguousByteBuffer & a_Data)
+{
+	if (m_IsEncrypted)
+	{
+		m_Encryptor.ProcessData(a_Data.data(), a_Data.size());
+	}
+}
+
+
+
+
+
 void cProtocol_1_8_0::SendAttachEntity(const cEntity & a_Entity, const cEntity & a_Vehicle)
 {
 	ASSERT(m_State == 3);  // In game mode?
@@ -370,7 +382,7 @@ void cProtocol_1_8_0::SendChunkData(const ContiguousByteBufferView a_ChunkData)
 	ASSERT(m_State == 3);  // In game mode?
 
 	cCSLock Lock(m_CSPacket);
-	SendData(a_ChunkData);
+	m_Client->SendData(a_ChunkData);
 }
 
 
@@ -3003,31 +3015,6 @@ void cProtocol_1_8_0::SendEntitySpawn(const cEntity & a_Entity, const UInt8 a_Ob
 
 
 
-void cProtocol_1_8_0::SendData(ContiguousByteBufferView a_Data)
-{
-	if (m_IsEncrypted)
-	{
-		std::byte Encrypted[8 KiB];  // Larger buffer, we may be sending lots of data (chunks)
-
-		while (a_Data.size() > 0)
-		{
-			const auto NumBytes = (a_Data.size() > sizeof(Encrypted)) ? sizeof(Encrypted) : a_Data.size();
-			m_Encryptor.ProcessData(Encrypted, a_Data.data(), NumBytes);
-			m_Client->SendData({ Encrypted, NumBytes });
-
-			a_Data = a_Data.substr(NumBytes);
-		}
-	}
-	else
-	{
-		m_Client->SendData(a_Data);
-	}
-}
-
-
-
-
-
 void cProtocol_1_8_0::SendPacket(cPacketizer & a_Pkt)
 {
 	ASSERT(m_OutPacketBuffer.GetReadableSpace() == m_OutPacketBuffer.GetUsedSpace());
@@ -3045,7 +3032,7 @@ void cProtocol_1_8_0::SendPacket(cPacketizer & a_Pkt)
 		cProtocol_1_8_0::CompressPacket(m_Compressor, CompressedPacket);
 
 		// Send the packet's payload compressed:
-		SendData(CompressedPacket);
+		m_Client->SendData(CompressedPacket);
 	}
 	else
 	{
@@ -3054,10 +3041,10 @@ void cProtocol_1_8_0::SendPacket(cPacketizer & a_Pkt)
 		ContiguousByteBuffer LengthData;
 		m_OutPacketLenBuffer.ReadAll(LengthData);
 		m_OutPacketLenBuffer.CommitRead();
-		SendData(LengthData);
+		m_Client->SendData(LengthData);
 
 		// Send the packet's payload directly:
-		SendData(PacketData);
+		m_Client->SendData(PacketData);
 	}
 
 	// Log the comm into logfile:

src/Protocol/Protocol_1_8.h

@@ -36,11 +36,10 @@ public:
 
 	cProtocol_1_8_0(cClientHandle * a_Client, const AString & a_ServerAddress, State a_State);
 
-	/** Called to process them, when client sends some data.
-	The protocol uses the provided buffers for storage and processing, and must have exclusive access to them. */
 	virtual void DataReceived(cByteBuffer & a_Buffer, ContiguousByteBuffer && a_Data) override;
+	virtual void DataPrepared(ContiguousByteBuffer & a_Data) override;
 
-	/** Sending stuff to clients (alphabetically sorted): */
+	// Sending stuff to clients (alphabetically sorted):
 	virtual void SendAttachEntity               (const cEntity & a_Entity, const cEntity & a_Vehicle) override;
 	virtual void SendBlockAction                (int a_BlockX, int a_BlockY, int a_BlockZ, char a_Byte1, char a_Byte2, BLOCKTYPE a_BlockType) override;
 	virtual void SendBlockBreakAnim	            (UInt32 a_EntityID, int a_BlockX, int a_BlockY, int a_BlockZ, char a_Stage) override;
@@ -216,9 +215,6 @@ protected:
 	/** Sends the entity type and entity-dependent data required for the entity to initially spawn. */
 	virtual void SendEntitySpawn(const cEntity & a_Entity, const UInt8 a_ObjectType, const Int32 a_ObjectData);
 
-	/** Sends the data to the client, encrypting them if needed. */
-	virtual void SendData(ContiguousByteBufferView a_Size) override;
-
 	/** Sends the packet to the client. Called by the cPacketizer's destructor. */
 	virtual void SendPacket(cPacketizer & a_Packet) override;
 

src/mbedTLS++/AesCfb128Encryptor.cpp

@@ -43,8 +43,8 @@ void cAesCfb128Encryptor::Init(const Byte a_Key[16], const Byte a_IV[16])
 
 
 
-void cAesCfb128Encryptor::ProcessData(std::byte * const a_EncryptedOut, const std::byte * const a_PlainIn, size_t a_Length)
+void cAesCfb128Encryptor::ProcessData(std::byte * const a_PlainIn, const size_t a_Length)
 {
 	ASSERT(IsValid());  // Must Init() first
-	mbedtls_aes_crypt_cfb8(&m_Aes, MBEDTLS_AES_ENCRYPT, a_Length, m_IV, reinterpret_cast<const unsigned char *>(a_PlainIn), reinterpret_cast<unsigned char *>(a_EncryptedOut));
+	mbedtls_aes_crypt_cfb8(&m_Aes, MBEDTLS_AES_ENCRYPT, a_Length, m_IV, reinterpret_cast<const unsigned char *>(a_PlainIn), reinterpret_cast<unsigned char *>(a_PlainIn));
 }

src/mbedTLS++/AesCfb128Encryptor.h

@@ -26,13 +26,14 @@ public:
 	/** Initializes the decryptor with the specified Key / IV */
 	void Init(const Byte a_Key[16], const Byte a_IV[16]);
 
-	/** Encrypts a_Length bytes of the plain data; produces a_Length output bytes */
+	/** Encrypts a_Length bytes of the plain data in-place; produces a_Length output bytes */
-	void ProcessData(std::byte * a_EncryptedOut, const std::byte * a_PlainIn, size_t a_Length);
+	void ProcessData(std::byte * a_PlainIn, size_t a_Length);
 
 	/** Returns true if the object has been initialized with the Key / IV */
 	bool IsValid(void) const { return m_IsValid; }
 
 protected:
+
 	mbedtls_aes_context m_Aes;
 
 	/** The InitialVector, used by the CFB mode encryption */
@@ -41,8 +42,3 @@ protected:
 	/** Indicates whether the object has been initialized with the Key / IV */
 	bool m_IsValid;
 } ;
-
-
-
-
-