I2P -> .NET

libdotnet/ChaCha20.h

@@ -0,0 +1,72 @@
+/*
+* Copyright (c) 2013-2018, The PurpleI2P Project
+*
+* This file is part of Purple dotnet project and licensed under BSD3
+*
+* See full license text in LICENSE file at top of project tree
+*
+* Kovri go write your own code
+*
+*/
+#ifndef LIBDOTNET_CHACHA20_H
+#define LIBDOTNET_CHACHA20_H
+#include <cstdint>
+#include <cstring>
+#include <inttypes.h>
+#include <string.h>
+#include "Crypto.h"
+
+#if !OPENSSL_AEAD_CHACHA20_POLY1305
+namespace dotnet
+{
+namespace crypto
+{
+ 	const std::size_t CHACHA20_KEY_BYTES = 32;
+  	const std::size_t CHACHA20_NOUNCE_BYTES = 12;
+	
+namespace chacha
+{
+	constexpr std::size_t blocksize = 64;	
+	constexpr int rounds = 20;
+
+	struct Chacha20State;
+	struct Chacha20Block
+	{
+	  Chacha20Block () {};
+	  Chacha20Block (Chacha20Block &&) = delete;
+
+	  uint8_t data[blocksize];
+
+	  void operator << (const Chacha20State & st);
+	};
+
+	struct Chacha20State
+	{
+		Chacha20State (): offset (0) {};
+		Chacha20State (Chacha20State &&) = delete;
+
+		Chacha20State & operator += (const Chacha20State & other)
+		{
+			for(int i = 0; i < 16; i++)
+				data[i] += other.data[i];
+			return *this;
+		}
+
+		void Copy(const Chacha20State & other)
+		{
+		   memcpy(data, other.data, sizeof(uint32_t) * 16);
+		}
+		uint32_t data[16];
+		Chacha20Block block;
+		size_t offset; 
+	};
+
+	void Chacha20Init (Chacha20State& state, const uint8_t * nonce, const uint8_t * key, uint32_t counter);
+	void Chacha20SetCounter (Chacha20State& state, uint32_t counter);
+	void Chacha20Encrypt (Chacha20State& state, uint8_t * buf, size_t sz); // encrypt buf in place	
+}
+} 
+}
+#endif
+
+#endif