// Copyright 2005-2019 The Mumble Developers. All rights reserved.
// Use of this source code is governed by a BSD-style license
// that can be found in the LICENSE file at the root of the
// Mumble source tree or at <https://www.mumble.info/LICENSE>.

#ifndef MUMBLE_CRYPTSTATE_H_
#define MUMBLE_CRYPTSTATE_H_

#include <openssl/aes.h>

#define AES_KEY_SIZE_BITS   128
#define AES_KEY_SIZE_BYTES  (AES_KEY_SIZE_BITS/8)

#include "Timer.h"

class CryptState {
	private:
		Q_DISABLE_COPY(CryptState)
	public:
		unsigned char raw_key[AES_KEY_SIZE_BYTES];
		unsigned char encrypt_iv[AES_BLOCK_SIZE];
		unsigned char decrypt_iv[AES_BLOCK_SIZE];
		unsigned char decrypt_history[0x100];

		unsigned int uiGood;
		unsigned int uiLate;
		unsigned int uiLost;
		unsigned int uiResync;

		unsigned int uiRemoteGood;
		unsigned int uiRemoteLate;
		unsigned int uiRemoteLost;
		unsigned int uiRemoteResync;

		AES_KEY	encrypt_key;
		AES_KEY decrypt_key;
		Timer tLastGood;
		Timer tLastRequest;
		bool bInit;
		CryptState();

		bool isValid() const;
		void genKey();
		void setKey(const unsigned char *rkey, const unsigned char *eiv, const unsigned char *div);
		void setDecryptIV(const unsigned char *iv);

		bool ocb_encrypt(const unsigned char *plain, unsigned char *encrypted, unsigned int len, const unsigned char *nonce, unsigned char *tag,
				bool modifyPlainOnXEXStarAttack = true);
		bool ocb_decrypt(const unsigned char *encrypted, unsigned char *plain, unsigned int len, const unsigned char *nonce, unsigned char *tag);

		bool decrypt(const unsigned char *source, unsigned char *dst, unsigned int crypted_length);
		bool encrypt(const unsigned char *source, unsigned char *dst, unsigned int plain_length);
};

#endif
