/*
|
* Copyright (C) 2015 Southern Storm Software, Pty Ltd.
|
*
|
* Permission is hereby granted, free of charge, to any person obtaining a
|
* copy of this software and associated documentation files (the "Software"),
|
* to deal in the Software without restriction, including without limitation
|
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
|
* and/or sell copies of the Software, and to permit persons to whom the
|
* Software is furnished to do so, subject to the following conditions:
|
*
|
* The above copyright notice and this permission notice shall be included
|
* in all copies or substantial portions of the Software.
|
*
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
|
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
|
* DEALINGS IN THE SOFTWARE.
|
*/
|
|
#ifndef CRYPTO_GCM_h
|
#define CRYPTO_GCM_h
|
|
#include "AuthenticatedCipher.h"
|
#include "BlockCipher.h"
|
#include "GHASH.h"
|
|
class GCMCommon : public AuthenticatedCipher
|
{
|
public:
|
virtual ~GCMCommon();
|
|
size_t keySize() const;
|
size_t ivSize() const;
|
size_t tagSize() const;
|
|
bool setKey(const uint8_t *key, size_t len);
|
bool setIV(const uint8_t *iv, size_t len);
|
|
void encrypt(uint8_t *output, const uint8_t *input, size_t len);
|
void decrypt(uint8_t *output, const uint8_t *input, size_t len);
|
|
void addAuthData(const void *data, size_t len);
|
|
void computeTag(void *tag, size_t len);
|
bool checkTag(const void *tag, size_t len);
|
|
void clear();
|
|
protected:
|
GCMCommon();
|
void setBlockCipher(BlockCipher *cipher) { blockCipher = cipher; }
|
|
private:
|
BlockCipher *blockCipher;
|
GHASH ghash;
|
struct {
|
uint8_t counter[16];
|
uint8_t stream[16];
|
uint8_t nonce[16];
|
uint64_t authSize;
|
uint64_t dataSize;
|
bool dataStarted;
|
uint8_t posn;
|
} state;
|
};
|
|
template <typename T>
|
class GCM : public GCMCommon
|
{
|
public:
|
GCM() { setBlockCipher(&cipher); }
|
|
private:
|
T cipher;
|
};
|
|
#endif
|
