text: /**
  * Copyright (c) 2017-2050
  * All rights reserved.
  *
  * @Author:MXWXZ
  * @Date:2017/12/17
  *
  * @Description:adapted from 黑猫崽儿 http://blog.csdn.net/c_duoduo/article/details/43889759
  */
  #include "stdafx.h"
  #include "sha256.h"
  
  namespace CryptoLib {
  //////////////////////////////////////////////////////////////////////////
  #define SHA256_ROTL(a,b) (((a>>(32-b))&(0x7fffffff>>(31-b)))|(a<<b))
  #define SHA256_SR(a,b) ((a>>b)&(0x7fffffff>>(b-1)))
  #define SHA256_Ch(x,y,z) ((x&y)^((~x)&z))
  #define SHA256_Maj(x,y,z) ((x&y)^(x&z)^(y&z))
  #define SHA256_E0(x) (SHA256_ROTL(x,30)^SHA256_ROTL(x,19)^SHA256_ROTL(x,10))
  #define SHA256_E1(x) (SHA256_ROTL(x,26)^SHA256_ROTL(x,21)^SHA256_ROTL(x,7))
  #define SHA256_O0(x) (SHA256_ROTL(x,25)^SHA256_ROTL(x,14)^SHA256_SR(x,3))
  #define SHA256_O1(x) (SHA256_ROTL(x,15)^SHA256_ROTL(x,13)^SHA256_SR(x,10))
  //////////////////////////////////////////////////////////////////////////
  char* Hash_SHA256::StrSHA256(const char* str, long long length, char* sha256) {
      char *pp, *ppend;
      long l, i, W[64], T1, T2, A, B, C, D, E, F, G, H, H0, H1, H2, H3, H4, H5, H6, H7;
      H0 = 0x6a09e667, H1 = 0xbb67ae85, H2 = 0x3c6ef372, H3 = 0xa54ff53a;
      H4 = 0x510e527f, H5 = 0x9b05688c, H6 = 0x1f83d9ab, H7 = 0x5be0cd19;
      long K[64] = {
          0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
          0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
          0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
          0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
          0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
          0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
          0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
          0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,
      };
      l = (long)(length + ((length % 64 > 56) ? (128 - length % 64) : (64 - length % 64)));
      if (!(pp = (char*)malloc((unsigned long)l))) return 0;
      for (i = 0; i < length; pp[i + 3 - 2 * (i % 4)] = str[i], i++);
      for (pp[i + 3 - 2 * (i % 4)] = 128, i++; i < l; pp[i + 3 - 2 * (i % 4)] = 0, i++);
      *((long*)(pp + l - 4)) = (long)(length << 3);
      *((long*)(pp + l - 8)) = (long)(length >> 29);
      for (ppend = pp + l; pp < ppend; pp += 64) {
          for (i = 0; i < 16; W[i] = ((long*)pp)[i], i++);
          for (i = 16; i < 64; W[i] = (SHA256_O1(W[i - 2]) + W[i - 7] + SHA256_O0(W[i - 15]) + W[i - 16]), i++);
          A = H0, B = H1, C = H2, D = H3, E = H4, F = H5, G = H6, H = H7;
          for (i = 0; i < 64; i++) {
              T1 = H + SHA256_E1(E) + SHA256_Ch(E, F, G) + K[i] + W[i];
              T2 = SHA256_E0(A) + SHA256_Maj(A, B, C);
              H = G, G = F, F = E, E = D + T1, D = C, C = B, B = A, A = T1 + T2;
          }
          H0 += A, H1 += B, H2 += C, H3 += D, H4 += E, H5 += F, H6 += G, H7 += H;
      }
      free(pp - l);
      sprintf(sha256, "%08x%08x%08x%08x%08x%08x%08x%08x", H0, H1, H2, H3, H4, H5, H6, H7);
      return sha256;
  }
  char* Hash_SHA256::FileSHA256(const char* file, char* sha256) {
      FILE* fh;
      char* addlp, T[64];
      long addlsize, j, W[64], T1, T2, A, B, C, D, E, F, G, H, H0, H1, H2, H3, H4, H5, H6, H7;
      long long length, i, cpys;
      void *pp, *ppend;
      H0 = 0x6a09e667, H1 = 0xbb67ae85, H2 = 0x3c6ef372, H3 = 0xa54ff53a;
      H4 = 0x510e527f, H5 = 0x9b05688c, H6 = 0x1f83d9ab, H7 = 0x5be0cd19;
      long K[64] = {
          0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
          0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
          0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
          0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
          0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
          0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
          0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
          0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,
      };
      fh = fopen(file, "rb");
      assert(fh);
      fseek(fh, 0, SEEK_END);
      length = _ftelli64(fh);
      addlsize = (56 - length % 64 > 0) ? (64) : (128);
      if (!(addlp = (char*)malloc(addlsize))) return 0;
      cpys = ((length - (56 - length % 64)) > 0) ? (length - length % 64) : (0);
      j = (long)(length - cpys);
      if (!(pp = (char*)malloc(j))) return 0;
      fseek(fh, -j, SEEK_END);
      fread(pp, 1, j, fh);
      for (i = 0; i < j; addlp[i + 3 - 2 * (i % 4)] = ((char*)pp)[i], i++);
      free(pp);
      for (addlp[i + 3 - 2 * (i % 4)] = 128, i++; i < addlsize; addlp[i + 3 - 2 * (i % 4)] = 0, i++);
      *((long*)(addlp + addlsize - 4)) = (long)(length << 3);
      *((long*)(addlp + addlsize - 8)) = (long)(length >> 29);
      for (rewind(fh); 64 == fread(W, 1, 64, fh);) {
          for (i = 0; i < 64; T[i + 3 - 2 * (i % 4)] = ((char*)W)[i], i++);
          for (i = 0; i < 16; W[i] = ((long*)T)[i], i++);
          for (i = 16; i < 64; W[i] = (SHA256_O1(W[i - 2]) + W[i - 7] + SHA256_O0(W[i - 15]) + W[i - 16]), i++);
          A = H0, B = H1, C = H2, D = H3, E = H4, F = H5, G = H6, H = H7;
          for (i = 0; i < 64; i++) {
              T1 = H + SHA256_E1(E) + SHA256_Ch(E, F, G) + K[i] + W[i];
              T2 = SHA256_E0(A) + SHA256_Maj(A, B, C);
              H = G, G = F, F = E, E = D + T1, D = C, C = B, B = A, A = T1 + T2;
          }
          H0 += A, H1 += B, H2 += C, H3 += D, H4 += E, H5 += F, H6 += G, H7 += H;
      }
      for (pp = addlp, ppend = addlp + addlsize; pp < ppend; pp = (long*)pp + 16) {
          for (i = 0; i < 16; W[i] = ((long*)pp)[i], i++);
          for (i = 16; i < 64; W[i] = (SHA256_O1(W[i - 2]) + W[i - 7] + SHA256_O0(W[i - 15]) + W[i - 16]), i++);
          A = H0, B = H1, C = H2, D = H3, E = H4, F = H5, G = H6, H = H7;
          for (i = 0; i < 64; i++) {
              T1 = H + SHA256_E1(E) + SHA256_Ch(E, F, G) + K[i] + W[i];
              T2 = SHA256_E0(A) + SHA256_Maj(A, B, C);
              H = G, G = F, F = E, E = D + T1, D = C, C = B, B = A, A = T1 + T2;
          }
          H0 += A, H1 += B, H2 += C, H3 += D, H4 += E, H5 += F, H6 += G, H7 += H;
      }
      free(addlp); fclose(fh);
      sprintf(sha256, "%08x%08x%08x%08x%08x%08x%08x%08x", H0, H1, H2, H3, H4, H5, H6, H7);
      return sha256;
  }
  
  STRX Hash_SHA256::Generate(CSTRX dat) {
      string rec;
  #if CRYPTOLIB_ENABLE_UTF8ONLY
      rec = dat.GetUTF8Str().GetString();
  #else
      rec = dat.GetString();
  #endif
      const char* str = rec.c_str();
      char result[65];
      StrSHA256(str, strlen(str), result);
      return STRX(result);
  }
  
  STRX Hash_SHA256::GenerateFile(CSTRX filename) {
      char result[65];
      FileSHA256(filename.GetString().c_str(), result);
      return STRX(result);
  }
  }    // namespace CryptoLib
  