c/c++语言开发共享C++ 递归遍历文件并计算MD5的实例代码

    #ifndef md5_h      #define md5_h        #include <string>      #include <fstream>        /* type define */      typedef unsigned char byte;      typedef unsigned int uint32;        using std::string;      using std::ifstream;        /* md5 declaration. */      class md5 {      public:      md5();      md5(const void* input, size_t length);      md5(const string& str);      md5(ifstream& in);      void update(const void* input, size_t length);      void update(const string& str);      void update(ifstream& in);      const byte* digest();      string tostring();      void reset();        private:      void update(const byte* input, size_t length);      void final();      void transform(const byte block[64]);      void encode(const uint32* input, byte* output, size_t length);      void decode(const byte* input, uint32* output, size_t length);      string bytestohexstring(const byte* input, size_t length);        /* class uncopyable */      md5(const md5&);      md5& operator=(const md5&);        private:      uint32 _state[4]; /* state (abcd) */      uint32 _count[2]; /* number of bits, modulo 2^64 (low-order word first) */      byte _buffer[64]; /* input buffer */      byte _digest[16]; /* message digest */      bool _finished;   /* calculate finished ? */        static const byte padding[64]; /* padding for calculate */      static const char hex[16];      enum { buffer_size = 1024 };      };        #endif /*md5_h*/

     #include "md5.h"        using namespace std;        /* constants for md5transform routine. */      #define s11 7      #define s12 12      #define s13 17      #define s14 22      #define s21 5      #define s22 9      #define s23 14      #define s24 20      #define s31 4      #define s32 11      #define s33 16      #define s34 23      #define s41 6      #define s42 10      #define s43 15      #define s44 21          /* f, g, h and i are basic md5 functions.      */      #define f(x, y, z) (((x) & (y)) | ((~x) & (z)))      #define g(x, y, z) (((x) & (z)) | ((y) & (~z)))      #define h(x, y, z) ((x) ^ (y) ^ (z))      #define i(x, y, z) ((y) ^ ((x) | (~z)))        /* rotate_left rotates x left n bits.      */      #define rotate_left(x, n) (((x) << (n)) | ((x) >> (32-(n))))        /* ff, gg, hh, and ii transformations for rounds 1, 2, 3, and 4.      rotation is separate from addition to prevent recomputation.      */      #define ff(a, b, c, d, x, s, ac) {     (a) += f ((b), (c), (d)) + (x) + ac;     (a) = rotate_left ((a), (s));     (a) += (b);     }      #define gg(a, b, c, d, x, s, ac) {     (a) += g ((b), (c), (d)) + (x) + ac;     (a) = rotate_left ((a), (s));     (a) += (b);     }      #define hh(a, b, c, d, x, s, ac) {     (a) += h ((b), (c), (d)) + (x) + ac;     (a) = rotate_left ((a), (s));     (a) += (b);     }      #define ii(a, b, c, d, x, s, ac) {     (a) += i ((b), (c), (d)) + (x) + ac;     (a) = rotate_left ((a), (s));     (a) += (b);     }          const byte md5::padding[64] = { 0x80 };      const char md5::hex[16] = {      ‘0‘, ‘1‘, ‘2‘, ‘3‘,      ‘4‘, ‘5‘, ‘6‘, ‘7‘,      ‘8‘, ‘9‘, ‘a‘, ‘b‘,      ‘c‘, ‘d‘, ‘e‘, ‘f‘      };          /* default construct. */      md5::md5() {      reset();      }        /* construct a md5 object with a input buffer. */      md5::md5(const void* input, size_t length) {      reset();      update(input, length);      }        /* construct a md5 object with a string. */      md5::md5(const string& str) {      reset();      update(str);      }        /* construct a md5 object with a file. */      md5::md5(ifstream& in) {      reset();      update(in);      }        /* return the message-digest */      const byte* md5::digest() {        if (!_finished) {         _finished = true;         final();      }      return _digest;      }        /* reset the calculate state */      void md5::reset() {        _finished = false;      /* reset number of bits. */      _count[0] = _count[1] = 0;      /* load magic initialization constants. */      _state[0] = 0x67452301;      _state[1] = 0xefcdab89;      _state[2] = 0x98badcfe;      _state[3] = 0x10325476;      }        /* updating the context with a input buffer. */      void md5::update(const void* input, size_t length) {      update((const byte*)input, length);      }        /* updating the context with a string. */      void md5::update(const string& str) {      update((const byte*)str.c_str(), str.length());      }        /* updating the context with a file. */      void md5::update(ifstream& in) {        if (!in) {         return;      }        std::streamsize length;      char buffer[buffer_size];      while (!in.eof()) {         in.read(buffer, buffer_size);         length = in.gcount();         if (length > 0) {          update(buffer, length);         }      }      in.close();      }        /* md5 block update operation. continues an md5 message-digest      operation, processing another message block, and updating the      context.      */      void md5::update(const byte* input, size_t length) {        uint32 i, index, partlen;        _finished = false;        /* compute number of bytes mod 64 */      index = (uint32)((_count[0] >> 3) & 0x3f);        /* update number of bits */      if ((_count[0] += ((uint32)length << 3)) < ((uint32)length << 3)) {         ++_count[1];      }      _count[1] += ((uint32)length >> 29);        partlen = 64 - index;        /* transform as many times as possible. */      if (length >= partlen) {           memcpy(&_buffer[index], input, partlen);         transform(_buffer);           for (i = partlen; i + 63 < length; i += 64) {          transform(&input[i]);         }         index = 0;        } else {         i = 0;      }        /* buffer remaining input */      memcpy(&_buffer[index], &input[i], length - i);      }        /* md5 finalization. ends an md5 message-_digest operation, writing the      the message _digest and zeroizing the context.      */      void md5::final() {        byte bits[8];      uint32 oldstate[4];      uint32 oldcount[2];      uint32 index, padlen;        /* save current state and count. */      memcpy(oldstate, _state, 16);      memcpy(oldcount, _count, 8);        /* save number of bits */      encode(_count, bits, 8);        /* pad out to 56 mod 64. */      index = (uint32)((_count[0] >> 3) & 0x3f);      padlen = (index < 56) ? (56 - index) : (120 - index);      update(padding, padlen);        /* append length (before padding) */      update(bits, 8);        /* store state in digest */      encode(_state, _digest, 16);        /* restore current state and count. */      memcpy(_state, oldstate, 16);      memcpy(_count, oldcount, 8);      }        /* md5 basic transformation. transforms _state based on block. */      void md5::transform(const byte block[64]) {        uint32 a = _state[0], b = _state[1], c = _state[2], d = _state[3], x[16];        decode(block, x, 64);        /* round 1 */      ff (a, b, c, d, x[ 0], s11, 0xd76aa478); /* 1 */      ff (d, a, b, c, x[ 1], s12, 0xe8c7b756); /* 2 */      ff (c, d, a, b, x[ 2], s13, 0x242070db); /* 3 */      ff (b, c, d, a, x[ 3], s14, 0xc1bdceee); /* 4 */      ff (a, b, c, d, x[ 4], s11, 0xf57c0faf); /* 5 */      ff (d, a, b, c, x[ 5], s12, 0x4787c62a); /* 6 */      ff (c, d, a, b, x[ 6], s13, 0xa8304613); /* 7 */      ff (b, c, d, a, x[ 7], s14, 0xfd469501); /* 8 */      ff (a, b, c, d, x[ 8], s11, 0x698098d8); /* 9 */      ff (d, a, b, c, x[ 9], s12, 0x8b44f7af); /* 10 */      ff (c, d, a, b, x[10], s13, 0xffff5bb1); /* 11 */      ff (b, c, d, a, x[11], s14, 0x895cd7be); /* 12 */      ff (a, b, c, d, x[12], s11, 0x6b901122); /* 13 */      ff (d, a, b, c, x[13], s12, 0xfd987193); /* 14 */      ff (c, d, a, b, x[14], s13, 0xa679438e); /* 15 */      ff (b, c, d, a, x[15], s14, 0x49b40821); /* 16 */        /* round 2 */      gg (a, b, c, d, x[ 1], s21, 0xf61e2562); /* 17 */      gg (d, a, b, c, x[ 6], s22, 0xc040b340); /* 18 */      gg (c, d, a, b, x[11], s23, 0x265e5a51); /* 19 */      gg (b, c, d, a, x[ 0], s24, 0xe9b6c7aa); /* 20 */      gg (a, b, c, d, x[ 5], s21, 0xd62f105d); /* 21 */      gg (d, a, b, c, x[10], s22, 0x2441453); /* 22 */      gg (c, d, a, b, x[15], s23, 0xd8a1e681); /* 23 */      gg (b, c, d, a, x[ 4], s24, 0xe7d3fbc8); /* 24 */      gg (a, b, c, d, x[ 9], s21, 0x21e1cde6); /* 25 */      gg (d, a, b, c, x[14], s22, 0xc33707d6); /* 26 */      gg (c, d, a, b, x[ 3], s23, 0xf4d50d87); /* 27 */      gg (b, c, d, a, x[ 8], s24, 0x455a14ed); /* 28 */      gg (a, b, c, d, x[13], s21, 0xa9e3e905); /* 29 */      gg (d, a, b, c, x[ 2], s22, 0xfcefa3f8); /* 30 */      gg (c, d, a, b, x[ 7], s23, 0x676f02d9); /* 31 */      gg (b, c, d, a, x[12], s24, 0x8d2a4c8a); /* 32 */        /* round 3 */      hh (a, b, c, d, x[ 5], s31, 0xfffa3942); /* 33 */      hh (d, a, b, c, x[ 8], s32, 0x8771f681); /* 34 */      hh (c, d, a, b, x[11], s33, 0x6d9d6122); /* 35 */      hh (b, c, d, a, x[14], s34, 0xfde5380c); /* 36 */      hh (a, b, c, d, x[ 1], s31, 0xa4beea44); /* 37 */      hh (d, a, b, c, x[ 4], s32, 0x4bdecfa9); /* 38 */      hh (c, d, a, b, x[ 7], s33, 0xf6bb4b60); /* 39 */      hh (b, c, d, a, x[10], s34, 0xbebfbc70); /* 40 */      hh (a, b, c, d, x[13], s31, 0x289b7ec6); /* 41 */      hh (d, a, b, c, x[ 0], s32, 0xeaa127fa); /* 42 */      hh (c, d, a, b, x[ 3], s33, 0xd4ef3085); /* 43 */      hh (b, c, d, a, x[ 6], s34, 0x4881d05); /* 44 */      hh (a, b, c, d, x[ 9], s31, 0xd9d4d039); /* 45 */      hh (d, a, b, c, x[12], s32, 0xe6db99e5); /* 46 */      hh (c, d, a, b, x[15], s33, 0x1fa27cf8); /* 47 */      hh (b, c, d, a, x[ 2], s34, 0xc4ac5665); /* 48 */        /* round 4 */      ii (a, b, c, d, x[ 0], s41, 0xf4292244); /* 49 */      ii (d, a, b, c, x[ 7], s42, 0x432aff97); /* 50 */      ii (c, d, a, b, x[14], s43, 0xab9423a7); /* 51 */      ii (b, c, d, a, x[ 5], s44, 0xfc93a039); /* 52 */      ii (a, b, c, d, x[12], s41, 0x655b59c3); /* 53 */      ii (d, a, b, c, x[ 3], s42, 0x8f0ccc92); /* 54 */      ii (c, d, a, b, x[10], s43, 0xffeff47d); /* 55 */      ii (b, c, d, a, x[ 1], s44, 0x85845dd1); /* 56 */      ii (a, b, c, d, x[ 8], s41, 0x6fa87e4f); /* 57 */      ii (d, a, b, c, x[15], s42, 0xfe2ce6e0); /* 58 */      ii (c, d, a, b, x[ 6], s43, 0xa3014314); /* 59 */      ii (b, c, d, a, x[13], s44, 0x4e0811a1); /* 60 */      ii (a, b, c, d, x[ 4], s41, 0xf7537e82); /* 61 */      ii (d, a, b, c, x[11], s42, 0xbd3af235); /* 62 */      ii (c, d, a, b, x[ 2], s43, 0x2ad7d2bb); /* 63 */      ii (b, c, d, a, x[ 9], s44, 0xeb86d391); /* 64 */        _state[0] += a;      _state[1] += b;      _state[2] += c;      _state[3] += d;      }        /* encodes input (ulong) into output (byte). assumes length is      a multiple of 4.      */      void md5::encode(const uint32* input, byte* output, size_t length) {        for (size_t i = 0, j = 0; j < length; ++i, j += 4) {         output[j]= (byte)(input[i] & 0xff);         output[j + 1] = (byte)((input[i] >> 8) & 0xff);         output[j + 2] = (byte)((input[i] >> 16) & 0xff);         output[j + 3] = (byte)((input[i] >> 24) & 0xff);      }      }        /* decodes input (byte) into output (ulong). assumes length is      a multiple of 4.      */      void md5::decode(const byte* input, uint32* output, size_t length) {        for (size_t i = 0, j = 0; j < length; ++i, j += 4) {         output[i] = ((uint32)input[j]) | (((uint32)input[j + 1]) << 8) |         (((uint32)input[j + 2]) << 16) | (((uint32)input[j + 3]) << 24);      }      }        /* convert byte array to hex string. */      string md5::bytestohexstring(const byte* input, size_t length) {        string str;      str.reserve(length << 1);      for (size_t i = 0; i < length; ++i) {         int t = input[i];         int a = t / 16;         int b = t % 16;         str.append(1, hex[a]);         str.append(1, hex[b]);      }      return str;      }        /* convert digest to string value */      string md5::tostring() {      return bytestohexstring(digest(), 16);      }

     #include "md5.h"      #include <iostream>        using namespace std;        void printmd5(const string& str, md5& md5) {            cout << "md5("" << str << "") = " << md5.tostring() << endl;      }        int main() {             md5 md5;           md5.update("");           printmd5("", md5);             md5.update("a");           printmd5("a", md5);             md5.update("bc");           printmd5("abc", md5);             md5.update("defghijklmnopqrstuvwxyz");           printmd5("abcdefghijklmnopqrstuvwxyz", md5);             md5.reset();           md5.update("message digest");           printmd5("message digest", md5);             md5.reset();           md5.update(ifstream("d:\test.txt"));           printmd5("d:\test.txt", md5);            return 0;      }

  /*	遍历目录下所有文件,对比 md5  	path：文件夹路径（末尾不要有‘‘）  	format：要筛选的文件后缀名  	str_md5：md5 字符串  	isfound：是否匹配到与 str_md5 相等的 md5 值  */   void findallfile_md5(const char * path,const char * format,string str_md5,bool &isfound)  {  	// 路径末尾追加 ‘*.*‘      char newpath[200];      strcpy(newpath, path);      strcat(newpath, "\*.*");           // 找到目录下的第一个文件 #include <io.h>  	_finddata_t finddata;  	/*	文件信息结构体  		struct _finddata_t{               unsigned attrib;			// 文件属性               time_t time_create;		// 创建时的时间戳               time_t time_access;		// 最后一次被访问时的时间戳               time_t time_write;			// 最后一次被修改时的时间戳               _fsize_t size;				// 文件字节大小               char name[_max_fname];		// 文件名          };  	*/  	long handle = _findfirst(newpath, &finddata);  	if (handle == -1){return;}              	// 遍历文件和文件夹      while (_findnext(handle, &finddata) == 0){          // 文件夹  		if (finddata.attrib & _a_subdir){  			// 文件夹名不能有敏感字符 ‘.‘、‘..‘  			if (strcmp(finddata.name, ".") == 0 || strcmp(finddata.name, "..") == 0){continue;}                    			// 进入这个文件夹继续遍历              strcpy(newpath, path);              strcat(newpath, "\");              strcat(newpath, finddata.name);              findallfile_md5(newpath,format,str_md5,isfound);  		}  		// 文件          else{  			// 判断是不是指定后缀的文件              if(strstr( finddata.name,format)){                      // 输出（用来测试）  				//cout << "finddata.size = " << finddata.size << endl;  				//cout << "finddata.name = " << finddata.name << endl;  				//cout << "path = " << path << endl;  				  				// 取文件全路径  				string str_fullpath = path;  				str_fullpath+="\"; str_fullpath+=finddata.name;    				// 取文件 md5,判断是否匹配特征  				md5 md5;  				md5.reset();  				md5.update(ifstream(str_fullpath));  				if(md5.tostring() == str_md5){isfound = true;}              }          }      }    	// 关闭搜索句柄      _findclose(handle);      }

  	// 获取 %temp% 目录  	tchar lptemppathbuffer[max_path];  	gettemppath(max_path,lptemppathbuffer);    	// 删除末尾 ‘‘  	string str_temppath = lptemppathbuffer;  	str_temppath = str_temppath.substr(0,str_temppath.length()-1);    	// 遍历目录下所有 exe 文件,匹配 md5  	bool isfound = false;  	findallfile_md5(stringtocharp(str_temppath),".exe","52f5ce92c6f72c7e193b560bf4e76330",isfound);  	if(isfound){cout << "找到了！" << endl;;}

  #include "md5.h"    using namespace std;    /* constants for md5transform routine. */  #define s11 7  #define s12 12  #define s13 17  #define s14 22  #define s21 5  #define s22 9  #define s23 14  #define s24 20  #define s31 4  #define s32 11  #define s33 16  #define s34 23  #define s41 6  #define s42 10  #define s43 15  #define s44 21      /* f, g, h and i are basic md5 functions.  */  #define f(x, y, z) (((x) & (y)) | ((~x) & (z)))  #define g(x, y, z) (((x) & (z)) | ((y) & (~z)))  #define h(x, y, z) ((x) ^ (y) ^ (z))  #define i(x, y, z) ((y) ^ ((x) | (~z)))    /* rotate_left rotates x left n bits.  */  #define rotate_left(x, n) (((x) << (n)) | ((x) >> (32-(n))))    /* ff, gg, hh, and ii transformations for rounds 1, 2, 3, and 4.  rotation is separate from addition to prevent recomputation.  */  #define ff(a, b, c, d, x, s, ac) {   (a) += f ((b), (c), (d)) + (x) + ac;   (a) = rotate_left ((a), (s));   (a) += (b);   }  #define gg(a, b, c, d, x, s, ac) {   (a) += g ((b), (c), (d)) + (x) + ac;   (a) = rotate_left ((a), (s));   (a) += (b);   }  #define hh(a, b, c, d, x, s, ac) {   (a) += h ((b), (c), (d)) + (x) + ac;   (a) = rotate_left ((a), (s));   (a) += (b);   }  #define ii(a, b, c, d, x, s, ac) {   (a) += i ((b), (c), (d)) + (x) + ac;   (a) = rotate_left ((a), (s));   (a) += (b);   }      const byte md5::padding[64] = { 0x80 };  const char md5::hex[16] = {  '0', '1', '2', '3',  '4', '5', '6', '7',  '8', '9', 'a', 'b',  'c', 'd', 'e', 'f'  };      /* default construct. */  md5::md5() {      reset();  }    /* construct a md5 object with a input buffer. */  md5::md5(const void* input, size_t length) {      reset();      update(input, length);  }    /* construct a md5 object with a string. */  md5::md5(const string& str) {      reset();      update(str);  }    /* construct a md5 object with a file. */  md5::md5(ifstream& in) {      reset();      update(in);  }    /* return the message-digest */  const byte* md5::digest() {        if (!_finished) {          _finished = true;          final();      }      return _digest;  }    /* reset the calculate state */  void md5::reset() {        _finished = false;      /* reset number of bits. */      _count[0] = _count[1] = 0;      /* load magic initialization constants. */      _state[0] = 0x67452301;      _state[1] = 0xefcdab89;      _state[2] = 0x98badcfe;      _state[3] = 0x10325476;  }    /* updating the context with a input buffer. */  void md5::update(const void* input, size_t length) {      update((const byte*)input, length);  }    /* updating the context with a string. */  void md5::update(const string& str) {      update((const byte*)str.c_str(), str.length());  }    /* updating the context with a file. */  void md5::update(ifstream& in) {        if (!in) {          return;      }        std::streamsize length;      char buffer[buffer_size];      while (!in.eof()) {          in.read(buffer, buffer_size);          length = in.gcount();          if (length > 0) {              update(buffer, length);          }      }      in.close();  }    /* md5 block update operation. continues an md5 message-digest  operation, processing another message block, and updating the  context.  */  void md5::update(const byte* input, size_t length) {        uint32 i, index, partlen;        _finished = false;        /* compute number of bytes mod 64 */      index = (uint32)((_count[0] >> 3) & 0x3f);        /* update number of bits */      if ((_count[0] += ((uint32)length << 3)) < ((uint32)length << 3)) {          ++_count[1];      }      _count[1] += ((uint32)length >> 29);        partlen = 64 - index;        /* transform as many times as possible. */      if (length >= partlen) {            memcpy(&_buffer[index], input, partlen);          transform(_buffer);            for (i = partlen; i + 63 < length; i += 64) {              transform(&input[i]);          }          index = 0;        }      else {          i = 0;      }        /* buffer remaining input */      memcpy(&_buffer[index], &input[i], length - i);  }    /* md5 finalization. ends an md5 message-_digest operation, writing the  the message _digest and zeroizing the context.  */  void md5::final() {        byte bits[8];      uint32 oldstate[4];      uint32 oldcount[2];      uint32 index, padlen;        /* save current state and count. */      memcpy(oldstate, _state, 16);      memcpy(oldcount, _count, 8);        /* save number of bits */      encode(_count, bits, 8);        /* pad out to 56 mod 64. */      index = (uint32)((_count[0] >> 3) & 0x3f);      padlen = (index < 56) ? (56 - index) : (120 - index);      update(padding, padlen);        /* append length (before padding) */      update(bits, 8);        /* store state in digest */      encode(_state, _digest, 16);        /* restore current state and count. */      memcpy(_state, oldstate, 16);      memcpy(_count, oldcount, 8);  }    /* md5 basic transformation. transforms _state based on block. */  void md5::transform(const byte block[64]) {        uint32 a = _state[0], b = _state[1], c = _state[2], d = _state[3], x[16];        decode(block, x, 64);        /* round 1 */      ff(a, b, c, d, x[0], s11, 0xd76aa478); /* 1 */      ff(d, a, b, c, x[1], s12, 0xe8c7b756); /* 2 */      ff(c, d, a, b, x[2], s13, 0x242070db); /* 3 */      ff(b, c, d, a, x[3], s14, 0xc1bdceee); /* 4 */      ff(a, b, c, d, x[4], s11, 0xf57c0faf); /* 5 */      ff(d, a, b, c, x[5], s12, 0x4787c62a); /* 6 */      ff(c, d, a, b, x[6], s13, 0xa8304613); /* 7 */      ff(b, c, d, a, x[7], s14, 0xfd469501); /* 8 */      ff(a, b, c, d, x[8], s11, 0x698098d8); /* 9 */      ff(d, a, b, c, x[9], s12, 0x8b44f7af); /* 10 */      ff(c, d, a, b, x[10], s13, 0xffff5bb1); /* 11 */      ff(b, c, d, a, x[11], s14, 0x895cd7be); /* 12 */      ff(a, b, c, d, x[12], s11, 0x6b901122); /* 13 */      ff(d, a, b, c, x[13], s12, 0xfd987193); /* 14 */      ff(c, d, a, b, x[14], s13, 0xa679438e); /* 15 */      ff(b, c, d, a, x[15], s14, 0x49b40821); /* 16 */        /* round 2 */      gg(a, b, c, d, x[1], s21, 0xf61e2562); /* 17 */      gg(d, a, b, c, x[6], s22, 0xc040b340); /* 18 */      gg(c, d, a, b, x[11], s23, 0x265e5a51); /* 19 */      gg(b, c, d, a, x[0], s24, 0xe9b6c7aa); /* 20 */      gg(a, b, c, d, x[5], s21, 0xd62f105d); /* 21 */      gg(d, a, b, c, x[10], s22, 0x2441453); /* 22 */      gg(c, d, a, b, x[15], s23, 0xd8a1e681); /* 23 */      gg(b, c, d, a, x[4], s24, 0xe7d3fbc8); /* 24 */      gg(a, b, c, d, x[9], s21, 0x21e1cde6); /* 25 */      gg(d, a, b, c, x[14], s22, 0xc33707d6); /* 26 */      gg(c, d, a, b, x[3], s23, 0xf4d50d87); /* 27 */      gg(b, c, d, a, x[8], s24, 0x455a14ed); /* 28 */      gg(a, b, c, d, x[13], s21, 0xa9e3e905); /* 29 */      gg(d, a, b, c, x[2], s22, 0xfcefa3f8); /* 30 */      gg(c, d, a, b, x[7], s23, 0x676f02d9); /* 31 */      gg(b, c, d, a, x[12], s24, 0x8d2a4c8a); /* 32 */        /* round 3 */      hh(a, b, c, d, x[5], s31, 0xfffa3942); /* 33 */      hh(d, a, b, c, x[8], s32, 0x8771f681); /* 34 */      hh(c, d, a, b, x[11], s33, 0x6d9d6122); /* 35 */      hh(b, c, d, a, x[14], s34, 0xfde5380c); /* 36 */      hh(a, b, c, d, x[1], s31, 0xa4beea44); /* 37 */      hh(d, a, b, c, x[4], s32, 0x4bdecfa9); /* 38 */      hh(c, d, a, b, x[7], s33, 0xf6bb4b60); /* 39 */      hh(b, c, d, a, x[10], s34, 0xbebfbc70); /* 40 */      hh(a, b, c, d, x[13], s31, 0x289b7ec6); /* 41 */      hh(d, a, b, c, x[0], s32, 0xeaa127fa); /* 42 */      hh(c, d, a, b, x[3], s33, 0xd4ef3085); /* 43 */      hh(b, c, d, a, x[6], s34, 0x4881d05); /* 44 */      hh(a, b, c, d, x[9], s31, 0xd9d4d039); /* 45 */      hh(d, a, b, c, x[12], s32, 0xe6db99e5); /* 46 */      hh(c, d, a, b, x[15], s33, 0x1fa27cf8); /* 47 */      hh(b, c, d, a, x[2], s34, 0xc4ac5665); /* 48 */        /* round 4 */      ii(a, b, c, d, x[0], s41, 0xf4292244); /* 49 */      ii(d, a, b, c, x[7], s42, 0x432aff97); /* 50 */      ii(c, d, a, b, x[14], s43, 0xab9423a7); /* 51 */      ii(b, c, d, a, x[5], s44, 0xfc93a039); /* 52 */      ii(a, b, c, d, x[12], s41, 0x655b59c3); /* 53 */      ii(d, a, b, c, x[3], s42, 0x8f0ccc92); /* 54 */      ii(c, d, a, b, x[10], s43, 0xffeff47d); /* 55 */      ii(b, c, d, a, x[1], s44, 0x85845dd1); /* 56 */      ii(a, b, c, d, x[8], s41, 0x6fa87e4f); /* 57 */      ii(d, a, b, c, x[15], s42, 0xfe2ce6e0); /* 58 */      ii(c, d, a, b, x[6], s43, 0xa3014314); /* 59 */      ii(b, c, d, a, x[13], s44, 0x4e0811a1); /* 60 */      ii(a, b, c, d, x[4], s41, 0xf7537e82); /* 61 */      ii(d, a, b, c, x[11], s42, 0xbd3af235); /* 62 */      ii(c, d, a, b, x[2], s43, 0x2ad7d2bb); /* 63 */      ii(b, c, d, a, x[9], s44, 0xeb86d391); /* 64 */        _state[0] += a;      _state[1] += b;      _state[2] += c;      _state[3] += d;  }    /* encodes input (ulong) into output (byte). assumes length is  a multiple of 4.  */  void md5::encode(const uint32* input, byte* output, size_t length) {        for (size_t i = 0, j = 0; j < length; ++i, j += 4) {          output[j] = (byte)(input[i] & 0xff);          output[j + 1] = (byte)((input[i] >> 8) & 0xff);          output[j + 2] = (byte)((input[i] >> 16) & 0xff);          output[j + 3] = (byte)((input[i] >> 24) & 0xff);      }  }    /* decodes input (byte) into output (ulong). assumes length is  a multiple of 4.  */  void md5::decode(const byte* input, uint32* output, size_t length) {        for (size_t i = 0, j = 0; j < length; ++i, j += 4) {          output[i] = ((uint32)input[j]) | (((uint32)input[j + 1]) << 8) |              (((uint32)input[j + 2]) << 16) | (((uint32)input[j + 3]) << 24);      }  }    /* convert byte array to hex string. */  string md5::bytestohexstring(const byte* input, size_t length) {        string str;      str.reserve(length << 1);      for (size_t i = 0; i < length; ++i) {          int t = input[i];          int a = t / 16;          int b = t % 16;          str.append(1, hex[a]);          str.append(1, hex[b]);      }      return str;  }    /* convert digest to string value */  string md5::tostring() {      return bytestohexstring(digest(), 16);  }