NIS MD5

/* Implementation of MD5 */

#include
#include
#include
#include
#include

unsigned long leftrotate(unsigned long,int);
double myabs(double x);

int main()
{
clrscr();
char tempchar;
int m,h;
char fileName[75];
char message[1000];
FILE *fp;
char ch;
unsigned long temp;
unsigned long w[20];
int n;
unsigned long sineInt[64];
int i;

int r[64]={7,12,17,22,7,12,17,22,7,12,17,22,7,12,17,22,5,9,14,20,5,9,14,20,5,9,14,20,5,9,14,20,4,11,16,23,4,11,16,23,4,11,16,23,4,11,16,23,6,10,15,21,6,10,15,21,6,10,15,21,6,10,15,21};
for(i=0;i<64;i++)
{
sineInt[i]=(unsigned long)floor(myabs(sin(i+1)*pow(2,32)));
}
//printf("\nEnter name of the file containing message:");
fp=fopen("c:\\message.txt","r");

i=0;
while(!feof(fp))
{
ch=fgetc(fp);
message[i]=ch;
i++;
}
message[i-1]=0x80;
message[i]='\0';
int no_of_bits=strlen(message)*8;
int message_length=no_of_bits-8;
unsigned long msg_length=message_length;

int bits_to_pad=((512-(no_of_bits%512))+448)%512;

int j=0;
for (j=0;j{
message[i+j]=0x00;
}

message[i+j]='\0';
i=i+j;

unsigned char *ptrchar;
ptrchar= (unsigned char *)(&msg_length);
message[i]=ptrchar[0];
message[i+1]=ptrchar[1];
message[i+2]=ptrchar[2];
message[i+3]=ptrchar[3];
message[i+4]=0x00;
message[i+5]=0x00;
message[i+6]=0x00;
message[i+7]=0x00;

i=i+8;

unsigned long A,B,C,D;

A=0x67452301;
B=0xefcdab89;
C=0x98badcfe;
D=0x10325476;

unsigned long a,b,c,d,f,g;

char message_chunk[70];
int no_of_chunks=(i*8)/512;
int k;
for(j=0;j{
for(k=0;k<64;k++)
{
message_chunk[k]=message[(j*64)+k];
}

for(n=0;n<16;n++)
{
w[n]=*((unsigned long *)(&message_chunk[n*4]));
}


a=A;
b=B;
c=C;
d=D;

for(k=0;k<64;k++)
{
if (k>=0 && k<=15) //round one
{
f=(b & c) | ((~b) & d);
g=k;
}
else if(k>=16 && k<=31) //round two
{
f=(b & d) | (c & (~d));
g=(5*k+1) % 16;
}
else if(k>=32 && k<=47) //round three
{
f=b^c^d;
g=(3*k+5)%16;
}
else if(k>=48 && k<=63) //round four
{
f=c ^ (b | (~d));
g=(7*k)%16;
}
temp=d;
d=c;
c=b;
b=b+leftrotate((a+f+sineInt[k]+w[g]),r[k]);
a=temp;

}
A=A+a;
B=B+b;
C=C+c;
D=D+d;
}

printf("\nThe MD5 hash is:");
ptrchar=(unsigned char *)(&A);
for (h=0;h<4;h++)
printf("%0.2X",ptrchar[h]);
cout<<" ";

ptrchar=(unsigned char *)(&B);
for (h=0;h<4;h++)
printf("%0.2X",ptrchar[h]);
cout<<" ";

ptrchar=(unsigned char *)(&C);
for (h=0;h<4;h++)
printf("%0.2X",ptrchar[h]);
cout<<" ";

ptrchar=(unsigned char *)(&D);
for (h=0;h<4;h++)
printf("%0.2X",ptrchar[h]);

getch();
return 0;
}



//This function circularly left-shifts 'x' by 'c' bits
unsigned long leftrotate(unsigned long x,int c)
{
return ((x<>(32-c)));
}
double myabs(double x)
{
if (x<0)
return -1*x;
else
return x;
}


/*
OUTPUT

Enter name of the file containing message:abc.txt
The message is:The quick brown fox jumps over the lazy dog.
The MD5 hash is:E4D909C2 90D0FB1C A068FFAD DF22CBD0

Enter name of the file containing message:abc.txt
The message is:The quick brown fox jumps over the lazy dog
The MD5 hash is:9E107D9D 372BB682 6BD81D35 42A419D6
*/