MD5加密算法
MD5功能:
1.输入任意长度的信息,经过处理,输出为128位的信息(数字指纹);
2.不同的输入得到的不同的结果(唯一性);
3.根据128位的输出结果不可能反推出输入的信息(不可逆);
MD5使用:添加下面的头文件和实现文件
string c,key; c="203"; MD5 iMD5; iMD5.GenerateMD5( (unsigned char*)c.c_str(), c.size() ); key = iMD5.ToString();
头文件:
#ifndef _CMD5_H #define _CMD5_H //#pragma warning(disable:4786) #include <string> using namespace std; /*! * Manage MD5. */ class MD5 { private: #define uint8 unsigned char #define uint32 unsigned long int struct md5_context { uint32 total[2]; uint32 state[4]; uint8 buffer[64]; }; void md5_starts( struct md5_context *ctx ); void md5_process( struct md5_context *ctx, uint8 data[64] ); void md5_update( struct md5_context *ctx, uint8 *input, uint32 length ); void md5_finish( struct md5_context *ctx, uint8 digest[16] ); public: //! construct a CMD5 from any buffer void GenerateMD5(unsigned char* buffer,int bufferlen); //! construct a CMD5 MD5(); //! construct a md5src from char * MD5(const char * md5src); //! construct a CMD5 from a 16 bytes md5 MD5(unsigned long* md5src); //! add a other md5 MD5 operator +(MD5 adder); //! just if equal bool operator ==(MD5 cmper); //! give the value from equer // void operator =(CMD5 equer); //! to a string string ToString(); unsigned long m_data[4]; }; #endif /* md5.h */
实现文件:
/* * RFC 1321 compliant MD5 implementation, * by Christophe Devine <devine@cr0.net>; * this program is licensed under the GPL. */ #include "Md5.h" #include <stdio.h> #include <stdlib.h> #include <string.h> #define GET_UINT32(n,b,i) \ { \ (n) = (uint32) ((uint8 *) b)[(i)] \ | (((uint32) ((uint8 *) b)[(i)+1]) << 8) \ | (((uint32) ((uint8 *) b)[(i)+2]) << 16) \ | (((uint32) ((uint8 *) b)[(i)+3]) << 24); \ } #define PUT_UINT32(n,b,i) \ { \ (((uint8 *) b)[(i)] ) = (uint8) (((n) ) & 0xFF); \ (((uint8 *) b)[(i)+1]) = (uint8) (((n) >> 8) & 0xFF); \ (((uint8 *) b)[(i)+2]) = (uint8) (((n) >> 16) & 0xFF); \ (((uint8 *) b)[(i)+3]) = (uint8) (((n) >> 24) & 0xFF); \ } //extern pthread_mutex_t mutexMemory; void MD5::md5_starts( struct md5_context *ctx ) { ctx->total[0] = 0; ctx->total[1] = 0; ctx->state[0] = 0x67452301; ctx->state[1] = 0xEFCDAB89; ctx->state[2] = 0x98BADCFE; ctx->state[3] = 0x10325476; } void MD5::md5_process( struct md5_context *ctx, uint8 data[64] ) { uint32 A, B, C, D, X[16]; GET_UINT32( X[0], data, 0 ); GET_UINT32( X[1], data, 4 ); GET_UINT32( X[2], data, 8 ); GET_UINT32( X[3], data, 12 ); GET_UINT32( X[4], data, 16 ); GET_UINT32( X[5], data, 20 ); GET_UINT32( X[6], data, 24 ); GET_UINT32( X[7], data, 28 ); GET_UINT32( X[8], data, 32 ); GET_UINT32( X[9], data, 36 ); GET_UINT32( X[10], data, 40 ); GET_UINT32( X[11], data, 44 ); GET_UINT32( X[12], data, 48 ); GET_UINT32( X[13], data, 52 ); GET_UINT32( X[14], data, 56 ); GET_UINT32( X[15], data, 60 ); #define S(x,n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n))) #define P(a,b,c,d,k,s,t) \ { \ a += F(b,c,d) + X[k] + t; a = S(a,s) + b; \ } A = ctx->state[0]; B = ctx->state[1]; C = ctx->state[2]; D = ctx->state[3]; #define F(x,y,z) (z ^ (x & (y ^ z))) P( A, B, C, D, 0, 7, 0xD76AA478 ); P( D, A, B, C, 1, 12, 0xE8C7B756 ); P( C, D, A, B, 2, 17, 0x242070DB ); P( B, C, D, A, 3, 22, 0xC1BDCEEE ); P( A, B, C, D, 4, 7, 0xF57C0FAF ); P( D, A, B, C, 5, 12, 0x4787C62A ); P( C, D, A, B, 6, 17, 0xA8304613 ); P( B, C, D, A, 7, 22, 0xFD469501 ); P( A, B, C, D, 8, 7, 0x698098D8 ); P( D, A, B, C, 9, 12, 0x8B44F7AF ); P( C, D, A, B, 10, 17, 0xFFFF5BB1 ); P( B, C, D, A, 11, 22, 0x895CD7BE ); P( A, B, C, D, 12, 7, 0x6B901122 ); P( D, A, B, C, 13, 12, 0xFD987193 ); P( C, D, A, B, 14, 17, 0xA679438E ); P( B, C, D, A, 15, 22, 0x49B40821 ); #undef F #define F(x,y,z) (y ^ (z & (x ^ y))) P( A, B, C, D, 1, 5, 0xF61E2562 ); P( D, A, B, C, 6, 9, 0xC040B340 ); P( C, D, A, B, 11, 14, 0x265E5A51 ); P( B, C, D, A, 0, 20, 0xE9B6C7AA ); P( A, B, C, D, 5, 5, 0xD62F105D ); P( D, A, B, C, 10, 9, 0x02441453 ); P( C, D, A, B, 15, 14, 0xD8A1E681 ); P( B, C, D, A, 4, 20, 0xE7D3FBC8 ); P( A, B, C, D, 9, 5, 0x21E1CDE6 ); P( D, A, B, C, 14, 9, 0xC33707D6 ); P( C, D, A, B, 3, 14, 0xF4D50D87 ); P( B, C, D, A, 8, 20, 0x455A14ED ); P( A, B, C, D, 13, 5, 0xA9E3E905 ); P( D, A, B, C, 2, 9, 0xFCEFA3F8 ); P( C, D, A, B, 7, 14, 0x676F02D9 ); P( B, C, D, A, 12, 20, 0x8D2A4C8A ); #undef F #define F(x,y,z) (x ^ y ^ z) P( A, B, C, D, 5, 4, 0xFFFA3942 ); P( D, A, B, C, 8, 11, 0x8771F681 ); P( C, D, A, B, 11, 16, 0x6D9D6122 ); P( B, C, D, A, 14, 23, 0xFDE5380C ); P( A, B, C, D, 1, 4, 0xA4BEEA44 ); P( D, A, B, C, 4, 11, 0x4BDECFA9 ); P( C, D, A, B, 7, 16, 0xF6BB4B60 ); P( B, C, D, A, 10, 23, 0xBEBFBC70 ); P( A, B, C, D, 13, 4, 0x289B7EC6 ); P( D, A, B, C, 0, 11, 0xEAA127FA ); P( C, D, A, B, 3, 16, 0xD4EF3085 ); P( B, C, D, A, 6, 23, 0x04881D05 ); P( A, B, C, D, 9, 4, 0xD9D4D039 ); P( D, A, B, C, 12, 11, 0xE6DB99E5 ); P( C, D, A, B, 15, 16, 0x1FA27CF8 ); P( B, C, D, A, 2, 23, 0xC4AC5665 ); #undef F #define F(x,y,z) (y ^ (x | ~z)) P( A, B, C, D, 0, 6, 0xF4292244 ); P( D, A, B, C, 7, 10, 0x432AFF97 ); P( C, D, A, B, 14, 15, 0xAB9423A7 ); P( B, C, D, A, 5, 21, 0xFC93A039 ); P( A, B, C, D, 12, 6, 0x655B59C3 ); P( D, A, B, C, 3, 10, 0x8F0CCC92 ); P( C, D, A, B, 10, 15, 0xFFEFF47D ); P( B, C, D, A, 1, 21, 0x85845DD1 ); P( A, B, C, D, 8, 6, 0x6FA87E4F ); P( D, A, B, C, 15, 10, 0xFE2CE6E0 ); P( C, D, A, B, 6, 15, 0xA3014314 ); P( B, C, D, A, 13, 21, 0x4E0811A1 ); P( A, B, C, D, 4, 6, 0xF7537E82 ); P( D, A, B, C, 11, 10, 0xBD3AF235 ); P( C, D, A, B, 2, 15, 0x2AD7D2BB ); P( B, C, D, A, 9, 21, 0xEB86D391 ); #undef F ctx->state[0] += A; ctx->state[1] += B; ctx->state[2] += C; ctx->state[3] += D; } void MD5::md5_update( struct md5_context *ctx, uint8 *input, uint32 length ) { uint32 left, fill; if( ! length ) return; left = ( ctx->total[0] >> 3 ) & 0x3F; fill = 64 - left; ctx->total[0] += length << 3; ctx->total[1] += length >> 29; ctx->total[0] &= 0xFFFFFFFF; ctx->total[1] += ctx->total[0] < length << 3; if( left && length >= fill ) { memcpy( (void *) (ctx->buffer + left), (void *) input, fill ); md5_process( ctx, ctx->buffer ); length -= fill; input += fill; left = 0; } while( length >= 64 ) { md5_process( ctx, input ); length -= 64; input += 64; } if( length ) { memcpy( (void *) (ctx->buffer + left), (void *) input, length ); } } static uint8 md5_padding[64] = { 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; void MD5::md5_finish( struct md5_context *ctx, uint8 digest[16] ) { uint32 last, padn; uint8 msglen[8]; PUT_UINT32( ctx->total[0], msglen, 0 ); PUT_UINT32( ctx->total[1], msglen, 4 ); last = ( ctx->total[0] >> 3 ) & 0x3F; padn = ( last < 56 ) ? ( 56 - last ) : ( 120 - last ); md5_update( ctx, md5_padding, padn ); md5_update( ctx, msglen, 8 ); PUT_UINT32( ctx->state[0], digest, 0 ); PUT_UINT32( ctx->state[1], digest, 4 ); PUT_UINT32( ctx->state[2], digest, 8 ); PUT_UINT32( ctx->state[3], digest, 12 ); } void MD5::GenerateMD5(unsigned char* buffer,int bufferlen) { struct md5_context context; md5_starts (&context); md5_update (&context, buffer, bufferlen); md5_finish (&context,(unsigned char*)m_data); } MD5::MD5() { for(int i=0;i<4;i++) m_data[i]=0; } MD5::MD5(unsigned long* md5src) { memcpy(m_data,md5src,16); } int _httoi(const char *value) { struct CHexMap { char chr; int value; }; const int HexMapL = 16; CHexMap HexMap[HexMapL] = { {'0', 0}, {'1', 1}, {'2', 2}, {'3', 3}, {'4', 4}, {'5', 5}, {'6', 6}, {'7', 7}, {'8', 8}, {'9', 9}, {'a', 10}, {'b', 11}, {'c', 12}, {'d', 13}, {'e', 14}, {'f', 15} }; //pthread_mutex_lock(&mutexMemory); char *mstr = strdup(value); //pthread_mutex_unlock(&mutexMemory); char *s = mstr; int result = 0; if (*s == '0' && *(s + 1) == 'X') s += 2; bool firsttime = true; while (*s != '/0') { bool found = false; for (int i = 0; i < HexMapL; i++) { if (*s == HexMap[i].chr) { if (!firsttime) result <<= 4; result |= HexMap[i].value; found = true; break; } } if (!found) break; s++; firsttime = false; } //pthread_mutex_lock(&mutexMemory); free(mstr); //pthread_mutex_unlock(&mutexMemory); return result; } MD5::MD5(const char* md5src) { if (strcmp(md5src,"")==0) { for(int i=0;i<4;i++) m_data[i]=0; return; } for(int j = 0; j < 16; j++ ) { char buf[10]; strncpy(buf,md5src,2); md5src+=2; ((unsigned char*)m_data)[j] = _httoi(buf); } } MD5 MD5::operator +(MD5 adder) { unsigned long m_newdata[4]; for(int i=0;i<4;i++) m_newdata[i]=m_data[i]^(adder.m_data[i]); return MD5(m_newdata); } bool MD5::operator ==(MD5 cmper) { return (memcmp(cmper.m_data ,m_data,16)==0); } //void MD5::operator =(MD5 equer) //{ // memcpy(m_data,equer.m_data ,16); //} string MD5::ToString() { char output[33]; for(int j = 0; j < 16; j++ ) { sprintf( output + j * 2, "%02x", ((unsigned char*)m_data)[j]); } return string(output); }