don't create EVP_CIPHER_CTX for each AEAD/Chacha20/Poly1305 message

libi2pd/Crypto.h

@@ -187,10 +187,42 @@ namespace crypto
 	};
 
 // AEAD/ChaCha20/Poly1305
-	bool AEADChaCha20Poly1305 (const uint8_t * msg, size_t msgLen, const uint8_t * ad, size_t adLen, const uint8_t * key, const uint8_t * nonce, uint8_t * buf, size_t len, bool encrypt); // msgLen is len without tag
 
-	void AEADChaCha20Poly1305Encrypt (const std::vector<std::pair<uint8_t *, size_t> >& bufs, const uint8_t * key, const uint8_t * nonce, uint8_t * mac); // encrypt multiple buffers with zero ad
+	class AEADChaCha20Poly1305Encryptor
+	{
+		public:
 
+			AEADChaCha20Poly1305Encryptor ();
+			~AEADChaCha20Poly1305Encryptor ();
+
+			bool Encrypt (const uint8_t * msg, size_t msgLen, const uint8_t * ad, size_t adLen,
+				const uint8_t * key, const uint8_t * nonce, uint8_t * buf, size_t len); // msgLen is len without tag
+
+			void Encrypt (const std::vector<std::pair<uint8_t *, size_t> >& bufs, const uint8_t * key, const uint8_t * nonce, uint8_t * mac); // encrypt multiple buffers with zero ad
+			
+		private:
+
+			EVP_CIPHER_CTX * m_Ctx;	
+	};	
+
+	class AEADChaCha20Poly1305Decryptor
+	{
+		public:
+
+			AEADChaCha20Poly1305Decryptor ();
+			~AEADChaCha20Poly1305Decryptor ();
+
+			bool Decrypt (const uint8_t * msg, size_t msgLen, const uint8_t * ad, size_t adLen,
+				const uint8_t * key, const uint8_t * nonce, uint8_t * buf, size_t len); // msgLen is len without tag
+			
+		private:
+
+			EVP_CIPHER_CTX * m_Ctx;	
+	};	
+	
+	bool AEADChaCha20Poly1305 (const uint8_t * msg, size_t msgLen, const uint8_t * ad, size_t adLen,
+		const uint8_t * key, const uint8_t * nonce, uint8_t * buf, size_t len, bool encrypt); // msgLen is len without tag
+	
 // ChaCha20
 	void ChaCha20 (const uint8_t * msg, size_t msgLen, const uint8_t * key, const uint8_t * nonce, uint8_t * out);