#include <Windows.h> //这里面有byte类型 ,这时一个windows下面是用的库包,利用这个库包实现了很多函数,但是只能在windows下用
#include <iostream>
#include <string.h>
#include <stdlib.h>
#include <math.h>
using namespace std;
//4个内联函数,因为常用,所以提高运行效率用内联来写.
/*4组计算函数*/
inline unsigned int F(unsigned int X, unsigned int Y, unsigned int Z)
{
return (X & Y) | ((~X) & Z);
}
inline unsigned int G(unsigned int X, unsigned int Y, unsigned int Z)
{
return (X & Z) | (Y & (~Z));
}
inline unsigned int H(unsigned int X, unsigned int Y, unsigned int Z)
{
return X ^ Y ^ Z;
}
inline unsigned int I(unsigned int X, unsigned int Y, unsigned int Z)
{
return Y ^ (X | (~Z));
}
/*4组计算函数结束*/
/*32位数循环左移实现函数roll*/
void ROL(unsigned int &s, unsigned short cx)
{
if (cx > 32)cx %= 32;//写成一行了,如果平移大于32了,就余等32.
s = (s << cx) | (s >> (32 - cx)); //如果左边是0,那么就取右边的.
return;
}
/*BL互转，接收UINT类型*/
void ltob(unsigned int &i)
{
unsigned int tmp = i;//保存副本
byte *psour = (byte*)&tmp, *pdes = (byte*)&i;
pdes += 3;//调整指针，准备左右调转
for (short i = 3; i >= 0; --i)
{
CopyMemory(pdes - i, psour + i, 1); //表示从psour+i 这个值赋值到pdes-i这个地址,复制的长度是1.
}
return;
}
/*
MD5循环计算函数，label=第几轮循环（1<=label<=4），lGroup数组=4个种子副本，M=数据（16组32位数指针）
种子数组排列方式: --A--D--C--B--，即 lGroup[0]=A; lGroup[1]=D; lGroup[2]=C; lGroup[3]=B;
*/
void AccLoop(unsigned short label, unsigned int *lGroup, void *M)
{
unsigned int *i1, *i2, *i3, *i4, TAcc, tmpi = 0; //定义:4个指针； T表累加器； 局部变量
typedef unsigned int(*clac)(unsigned int X, unsigned int Y, unsigned int Z); //定义函数类型
const unsigned int rolarray[4][4] = {
{ 7, 12, 17, 22 },
{ 5, 9, 14, 20 },
{ 4, 11, 16, 23 },
{ 6, 10, 15, 21 }
};//循环左移-位数表
const unsigned short mN[4][16] = {
{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 },
{ 1, 6, 11, 0, 5, 10, 15, 4, 9, 14, 3, 8, 13, 2, 7, 12 },
{ 5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2 },
{ 0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9 }
};//数据坐标表
const unsigned int *pM = static_cast<unsigned int*>(M);//转换类型为32位的Uint
TAcc = ((label - 1) * 16) + 1; //根据第几轮循环初始化T表累加器
clac clacArr[4] = { F, G, H, I }; //定义并初始化计算函数指针数组
/*一轮循环开始（16组->16次）*/
for (short i = 0; i < 16; ++i)
{
/*进行指针自变换*/
i1 = lGroup + ((0 + i) % 4);
i2 = lGroup + ((3 + i) % 4);
i3 = lGroup + ((2 + i) % 4);
i4 = lGroup + ((1 + i) % 4);
/*第一步计算开始: A+F(B,C,D)+M[i]+T[i+1] 注:第一步中直接计算T表*/
tmpi = (*i1 + clacArr[label - 1](*i2, *i3, *i4) + pM[(mN[label - 1][i])] + (unsigned int)(0x100000000UL * abs(sin((double)(TAcc + i)))));
ROL(tmpi, rolarray[label - 1][i % 4]);//第二步:循环左移
*i1 = *i2 + tmpi;//第三步:相加并赋值到种子
}
return;
}
/*接口函数，并执行数据填充*/
unsigned int* MD5(const char* mStr)
{
unsigned int mLen = strlen(mStr); //计算字符串长度
if (mLen < 0) return 0;
unsigned int FillSize = 448 - ((mLen * 8) % 512); //计算需填充的bit数
unsigned int FSbyte = FillSize / 8; //以字节表示的填充数
unsigned int BuffLen = mLen + 8 + FSbyte; //缓冲区长度或者说填充后的长度
unsigned char *md5Buff = new unsigned char[BuffLen]; //分配缓冲区
CopyMemory(md5Buff, mStr, mLen); //复制字符串到缓冲区
/*数据填充开始*/
md5Buff[mLen] = 0x80; //第一个bit填充1
ZeroMemory(&md5Buff[mLen + 1], FSbyte - 1); //其它bit填充0，另一可用函数为FillMemory
unsigned long long lenBit = mLen * 8ULL; //计算字符串长度，准备填充
CopyMemory(&md5Buff[mLen + FSbyte], &lenBit, 8); //填充长度
/*数据填充结束*/
/*运算开始*/
unsigned int LoopNumber = BuffLen / 64; //以16个字为一分组，计算分组数量
unsigned int A = 0x67452301, B = 0x0EFCDAB89, C = 0x98BADCFE, D = 0x10325476;//初始4个种子，小端类型
unsigned int *lGroup = new unsigned int[4]{ A, D, C, B}; //种子副本数组,并作为返回值返回
for (unsigned int Bcount = 0; Bcount < LoopNumber; ++Bcount) //分组大循环开始
{
/*进入4次计算的小循环*/
for (unsigned short Lcount = 0; Lcount < 4;)
{
AccLoop(++Lcount, lGroup, &md5Buff[Bcount * 64]);
}
/*数据相加作为下一轮的种子或者最终输出*/
A = (lGroup[0] += A);
B = (lGroup[3] += B);
C = (lGroup[2] += C);
D = (lGroup[1] += D);
}
/*转换内存中的布局后才能正常显示*/
ltob(lGroup[0]);
ltob(lGroup[1]);
ltob(lGroup[2]);
ltob(lGroup[3]);
delete[] md5Buff; //清除内存并返回
return lGroup;
}
int main(){
char *a="dfdsasdf";
cout<<MD5(a)[0]<<endl;
cout<<MD5(a)[1]<<endl;
cout<<MD5(a)[2]<<endl;
cout<<MD5(a)[3]<<endl;
}