text: // Crypto/Sha1.cpp
  // This file is based on public domain
  // Steve Reid and Wei Dai's code from Crypto++
  
  #include "StdAfx.h"
  
  #include "../../../C/RotateDefs.h"
  
  #include "Sha1.h"
  
  namespace NCrypto {
  namespace NSha1 {
  
  // define it for speed optimization
  // #define _SHA1_UNROLL
  
  static const unsigned kNumW =
    #ifdef _SHA1_UNROLL
    16;
    #else
    80;
    #endif
    
  
  #define w0(i) (W[(i)] = data[(i)])
  
  #ifdef _SHA1_UNROLL
  #define w1(i) (W[(i)&15] = rotlFixed(W[((i)-3)&15] ^ W[((i)-8)&15] ^ W[((i)-14)&15] ^ W[((i)-16)&15], 1))
  #else
  #define w1(i) (W[(i)] = rotlFixed(W[(i)-3] ^ W[(i)-8] ^ W[(i)-14] ^ W[(i)-16], 1))
  #endif
  
  #define f1(x,y,z) (z^(x&(y^z)))
  #define f2(x,y,z) (x^y^z)
  #define f3(x,y,z) ((x&y)|(z&(x|y)))
  #define f4(x,y,z) (x^y^z)
  
  #define RK1(a,b,c,d,e,i, f, w, k) e += f(b,c,d) + w(i) + k + rotlFixed(a,5); b = rotlFixed(b,30);
  
  #define R0(a,b,c,d,e,i) RK1(a,b,c,d,e,i, f1, w0, 0x5A827999)
  #define R1(a,b,c,d,e,i) RK1(a,b,c,d,e,i, f1, w1, 0x5A827999)
  #define R2(a,b,c,d,e,i) RK1(a,b,c,d,e,i, f2, w1, 0x6ED9EBA1)
  #define R3(a,b,c,d,e,i) RK1(a,b,c,d,e,i, f3, w1, 0x8F1BBCDC)
  #define R4(a,b,c,d,e,i) RK1(a,b,c,d,e,i, f4, w1, 0xCA62C1D6)
  
  #define RX_1_4(rx1, rx4, i) rx1(a,b,c,d,e,i); rx4(e,a,b,c,d,i+1); rx4(d,e,a,b,c,i+2); rx4(c,d,e,a,b,i+3); rx4(b,c,d,e,a,i+4);
  #define RX_5(rx, i) RX_1_4(rx, rx, i);
  
  void CContextBase::Init()
  {
    _state[0] = 0x67452301;
    _state[1] = 0xEFCDAB89;
    _state[2] = 0x98BADCFE;
    _state[3] = 0x10325476;
    _state[4] = 0xC3D2E1F0;
    _count = 0;
  }
  
  void CContextBase::GetBlockDigest(UInt32 *data, UInt32 *destDigest, bool returnRes)
  {
    UInt32 a, b, c, d, e;
    UInt32 W[kNumW];
  
    a = _state[0];
    b = _state[1];
    c = _state[2];
    d = _state[3];
    e = _state[4];
    #ifdef _SHA1_UNROLL
    RX_5(R0, 0); RX_5(R0, 5); RX_5(R0, 10);
    #else
    int i;
    for (i = 0; i < 15; i += 5) { RX_5(R0, i); }
    #endif
  
    RX_1_4(R0, R1, 15);
  
  
    #ifdef _SHA1_UNROLL
    RX_5(R2, 20); RX_5(R2, 25); RX_5(R2, 30); RX_5(R2, 35);
    RX_5(R3, 40); RX_5(R3, 45); RX_5(R3, 50); RX_5(R3, 55);
    RX_5(R4, 60); RX_5(R4, 65); RX_5(R4, 70); RX_5(R4, 75);
    #else
    i = 20;
    for (; i < 40; i += 5) { RX_5(R2, i); }
    for (; i < 60; i += 5) { RX_5(R3, i); }
    for (; i < 80; i += 5) { RX_5(R4, i); }
    #endif
  
    destDigest[0] = _state[0] + a;
    destDigest[1] = _state[1] + b;
    destDigest[2] = _state[2] + c;
    destDigest[3] = _state[3] + d;
    destDigest[4] = _state[4] + e;
  
    if (returnRes)
      for (int i = 0 ; i < 16; i++)
        data[i] = W[kNumW - 16 + i];
    
    // Wipe variables
    // a = b = c = d = e = 0;
  }
  
  void CContextBase::PrepareBlock(UInt32 *block, unsigned size) const
  {
    unsigned curBufferPos = size & 0xF;
    block[curBufferPos++] = 0x80000000;
    while (curBufferPos != (16 - 2))
      block[curBufferPos++] = 0;
    const UInt64 lenInBits = (_count << 9) + ((UInt64)size << 5);
    block[curBufferPos++] = (UInt32)(lenInBits >> 32);
    block[curBufferPos++] = (UInt32)(lenInBits);
  }
  
  void CContext::Update(const Byte *data, size_t size)
  {
    unsigned curBufferPos = _count2;
    while (size--)
    {
      int pos = (int)(curBufferPos & 3);
      if (pos == 0)
        _buffer[curBufferPos >> 2] = 0;
      _buffer[curBufferPos >> 2] |= ((UInt32)*data++) << (8 * (3 - pos));
      if (++curBufferPos == kBlockSize)
      {
        curBufferPos = 0;
        CContextBase::UpdateBlock(_buffer, false);
      }
    }
    _count2 = curBufferPos;
  }
  
  void CContext::UpdateRar(Byte *data, size_t size, bool rar350Mode)
  {
    bool returnRes = false;
    unsigned curBufferPos = _count2;
    while (size--)
    {
      int pos = (int)(curBufferPos & 3);
      if (pos == 0)
        _buffer[curBufferPos >> 2] = 0;
      _buffer[curBufferPos >> 2] |= ((UInt32)*data++) << (8 * (3 - pos));
      if (++curBufferPos == kBlockSize)
      {
        curBufferPos = 0;
        CContextBase::UpdateBlock(_buffer, returnRes);
        if (returnRes)
          for (int i = 0; i < kBlockSizeInWords; i++)
          {
            UInt32 d = _buffer[i];
            data[i * 4 + 0 - kBlockSize] = (Byte)(d);
            data[i * 4 + 1 - kBlockSize] = (Byte)(d >>  8);
            data[i * 4 + 2 - kBlockSize] = (Byte)(d >> 16);
            data[i * 4 + 3 - kBlockSize] = (Byte)(d >> 24);
          }
        returnRes = rar350Mode;
      }
    }
    _count2 = curBufferPos;
  }
  
  void CContext::Final(Byte *digest)
  {
    const UInt64 lenInBits = (_count << 9) + ((UInt64)_count2 << 3);
    unsigned curBufferPos = _count2;
    int pos = (int)(curBufferPos & 3);
    curBufferPos >>= 2;
    if (pos == 0)
      _buffer[curBufferPos] = 0;
    _buffer[curBufferPos++] |= ((UInt32)0x80) << (8 * (3 - pos));
  
    while (curBufferPos != (16 - 2))
    {
      curBufferPos &= 0xF;
      if (curBufferPos == 0)
        UpdateBlock();
      _buffer[curBufferPos++] = 0;
    }
    _buffer[curBufferPos++] = (UInt32)(lenInBits >> 32);
    _buffer[curBufferPos++] = (UInt32)(lenInBits);
    UpdateBlock();
  
    int i;
    for (i = 0; i < kDigestSizeInWords; i++)
    {
      UInt32 state = _state[i] & 0xFFFFFFFF;
      *digest++ = (Byte)(state >> 24);
      *digest++ = (Byte)(state >> 16);
      *digest++ = (Byte)(state >> 8);
      *digest++ = (Byte)(state);
    }
    Init();
  }
  
  ///////////////////////////
  // Words version
  
  void CContext32::Update(const UInt32 *data, size_t size)
  {
    while (size--)
    {
      _buffer[_count2++] = *data++;
      if (_count2 == kBlockSizeInWords)
      {
        _count2 = 0;
        UpdateBlock();
      }
    }
  }
  
  void CContext32::Final(UInt32 *digest)
  {
    const UInt64 lenInBits = (_count << 9) + ((UInt64)_count2 << 5);
    unsigned curBufferPos = _count2;
    _buffer[curBufferPos++] = 0x80000000;
    while (curBufferPos != (16 - 2))
    {
      curBufferPos &= 0xF;
      if (curBufferPos == 0)
        UpdateBlock();
      _buffer[curBufferPos++] = 0;
    }
    _buffer[curBufferPos++] = (UInt32)(lenInBits >> 32);
    _buffer[curBufferPos++] = (UInt32)(lenInBits);
    GetBlockDigest(_buffer, digest);
    Init();
  }
  
  }}
  