easy7zip/CPP/7zip/Crypto/Sha1.h

// Crypto/Sha1.h
// This file is based on public domain
// Steve Reid and Wei Dai's code from Crypto++

#ifndef __CRYPTO_SHA1_H
#define __CRYPTO_SHA1_H

#include <stddef.h>

#include "../../Common/MyTypes.h"

// Sha1 implementation in RAR before version 3.60 has bug:
// it changes data bytes in some cases.
// So this class supports both versions: normal_SHA and rar3Mode

namespace NCrypto {
namespace NSha1 {

const unsigned kBlockSize = 64;
const unsigned kDigestSize = 20;

const unsigned kBlockSizeInWords = (kBlockSize >> 2);
const unsigned kDigestSizeInWords = (kDigestSize >> 2);

class CContextBase
{
protected:
  UInt32 _state[5];
  UInt64 _count;
  void UpdateBlock(UInt32 *data, bool returnRes = false)
  {
    GetBlockDigest(data, _state, returnRes);
    _count++;
  }
public:
  void Init();
  void GetBlockDigest(UInt32 *blockData, UInt32 *destDigest, bool returnRes = false);
  // PrepareBlock can be used only when size <= 13. size in Words
  void PrepareBlock(UInt32 *block, unsigned int size) const;
};

class CContextBase2: public CContextBase
{
protected:
  unsigned _count2;
  UInt32 _buffer[kBlockSizeInWords];
  void UpdateBlock() { CContextBase::UpdateBlock(_buffer); }
public:
  void Init() { CContextBase::Init(); _count2 = 0; }
};

class CContext: public CContextBase2
{
public:
  void Update(const Byte *data, size_t size);
  void UpdateRar(Byte *data, size_t size, bool rar350Mode);
  void Final(Byte *digest);
};

class CContext32: public CContextBase2
{
public:
  void Update(const UInt32 *data, size_t size);
  void Final(UInt32 *digest);
};

}}

#endif