MD5

/************************************************************
MD5校验和计算小程序（C）
************************************************************/

#ifndef __MD5_INCLUDED__
#define __MD5_INCLUDED__


//MD5摘要值结构体
typedef struct MD5VAL_STRUCT
{
    unsigned int a;
    unsigned int b;
    unsigned int c;
    unsigned int d;
} MD5VAL;

//计算字符串的MD5值(若不指定长度则由函数计算)
MD5VAL md5(char * str, unsigned int size=0);

//MD5文件摘要
MD5VAL md5File(FILE * fpin);

//直接计算文件MD5
char * md5FileValue(char * fname);

//字符串md5加密
void md5Str(char * input, char * output);

#endif

/************************************************************
MD5校验和计算程序（C）
************************************************************/

//DEFINES for MD5
#include "stdafx.h"

#define UINT4 unsigned int


/* 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) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }
#define GG(a, b, c, d, x, s, ac) { \
 (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }
#define HH(a, b, c, d, x, s, ac) { \
 (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }
#define II(a, b, c, d, x, s, ac) { \
 (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }

// Constants for MD5 Transform 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

//===============

#include <stdio.h>
#include <string.h>
#include "Md5.h"

//Endian convert: big <-> little
unsigned int conv(unsigned int a)
{
    unsigned int b=0;
    b|=(a<<24)&0xff000000;
    b|=(a<<8)&0x00ff0000;
    b|=(a>>8)&0x0000ff00;
    b|=(a>>24)&0x000000ff;
    return b;
}

//MD5摘要
MD5VAL md5(char * str, unsigned int size)
{
    if(size==0)
        size=strlen(str);
    unsigned int m=size%64;
    unsigned int lm=size-m;  //数据整块长度
    unsigned int ln;  //数据补位后长度
    if(m<56)
        ln=lm+64;
    else
        ln=lm+128;
    unsigned char * strw=new unsigned char[ln];
    unsigned int i;
    //复制原字串到缓冲区strw
    for(i=0;i<size;i++)
        strw[i]=str[i];
    //补位
    strw[i++]=0x80;
    for(i;i<ln-8;i++)
        strw[i]=0x00;
    //补长度
    unsigned int * x=(unsigned int *)(strw+i);
    *(x++)=size<<3;
    *(x++)=size>>29;
    //初始化MD5参数
    MD5VAL val={0x67452301,0xefcdab89,0x98badcfe,0x10325476};
    unsigned int &a=val.a, &b=val.b, &c=val.c, &d=val.d;
    unsigned int aa,bb,cc,dd;
    for(i=0;i<ln;i+=64)
    {
        x=(unsigned int *)(strw+i);
        // Save the values
        aa=a; bb=b; cc=c; dd=d;
        // 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 */
        // Add the original values
        a+=aa;
        b+=bb;
        c+=cc;
        d+=dd;
    }
    delete[] strw;
    return val;
}

#define BUFFER_SIZE 4096   //必须是64的倍数
static unsigned char * Buffer=NULL;
//MD5文件摘要
MD5VAL md5File(FILE * fpin)
{
    if(!Buffer)
        Buffer=new unsigned char[BUFFER_SIZE+64];
    unsigned char * buf=Buffer;
    MD5VAL val={0x67452301,0xefcdab89,0x98badcfe,0x10325476};
    unsigned int &a=val.a, &b=val.b, &c=val.c, &d=val.d;
    unsigned int aa,bb,cc,dd;
    unsigned int i,j,count,co;
    unsigned int * x;
    i=0;
    do
    {
        count=fread(buf,1,BUFFER_SIZE,fpin);
        i+=count;
        if(count==BUFFER_SIZE)
            co=BUFFER_SIZE;
        else
        {
            j=count;
            buf[j++]=0x80;
            for(j;j%64!=56;j++)
                buf[j]=0x00;
            *(unsigned int *)(buf+j)=i<<3; j+=4;
            *(unsigned int *)(buf+j)=i>>29; j+=4;
            co=j;
        }
        for(j=0;j<co;j+=64)
        {
            x=(unsigned int *)(buf+j);
            // Save the values
            aa=a; bb=b; cc=c; dd=d;
            // 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 */
            // Add the original values
            a+=aa;
            b+=bb;
            c+=cc;
            d+=dd;
        }

    } while(count==BUFFER_SIZE);
    return val;
}

/* 获得文件的MD5值 */
char * md5FileValue(char * fname)
{
    static char md5[33]={0};
    MD5VAL val;
    
    FILE * fp = nullptr;
    fopen_s(&fp,fname, "rb");
    if(fp)
    {
        val=md5File(fp);
        sprintf_s(md5, "%08x%08x%08x%08x",conv(val.a),conv(val.b),conv(val.c),conv(val.d));
        fclose(fp);
    }
    
    return md5;
}

/* 获得字串的MD5值 */
void md5Str(char * input, char * output)
{
    MD5VAL val;
    val=md5(input, strlen(input));
    sprintf_s(output, strlen(output),"%08x%08x%08x%08x",conv(val.a),conv(val.b),conv(val.c),conv(val.d));
    
}