NIS HMAC Implementation

#include
#include
#include

#define SIZE 64

typedef unsigned char uchar ;
int main ( int argc, char * argv[] )
{
FILE * kfp ;
FILE * ifp ;
FILE * ofp ;
FILE * tfp ;
uchar c[2] ;
uchar ch;
uchar key[SIZE] = { 0x00 } ;
uchar ipad[SIZE] ;
uchar opad[SIZE] ;
uchar command[100] ;
int i;

if ( 4 != argc )
{
printf( "Incorrect Usage!\n" ) ;
printf( "Correct Usage is ./hmac

" ) ;
}
for ( i = 0; i < SIZE; i++ )
{
ipad[i] = 0x36 ;
opad[i] = 0x5C ;
}


kfp = fopen( argv[1], "r+b" ) ;
ofp = fopen( argv[3], "w+b" ) ;
tfp = fopen( "temp", "w+b" ) ;

fread( key, sizeof( uchar ), SIZE, kfp ) ;
fclose ( kfp );

for ( i = 0; i < SIZE; i++ )
{
key[i] = key[i] ^ ipad[i] ;
}

fwrite( key, sizeof( uchar ), SIZE, tfp ) ;
fclose( tfp ) ;

sprintf( command, "cat %s >> temp", argv[2]) ;
system( command ) ;
system( "./md5 temp > temp1" ) ;

kfp = fopen( argv[1], "r+b" ) ;
fread( key, sizeof( uchar ), SIZE, kfp ) ;
fclose ( kfp );
for ( i = 0; i < SIZE; i++ )
{
key[i] = key[i] ^ opad[i] ;
fwrite( &key[i], sizeof( uchar ), 1, ofp ) ;
}

tfp = fopen( "temp1", "r+b" ) ;
for ( i = 0; i < 16; i++ )
{
fread( c, sizeof( uchar ), 2, tfp );
c[0] -= '0' ;
if ( c[0] > 9 )
{
c[0] = c[0] + '0' - 'a' + 10 ;
}

c[1] -= '0' ;
if ( c[1] > 9 )
{
c[1] = c[1] + '0' - 'a' + 10 ;
}
ch = ( c[0] << 4 ) | c[1] ;
fwrite( &ch, sizeof( uchar ), 1, ofp ) ;
}
fclose( ofp ) ;

sprintf( command, "./md5 %s > temp", argv[3] ) ;
system( command ) ;
system( "cat temp" ) ;
printf( "\n" ) ;

return 0;
}

//OUTPUT:

root@root:~$ ./a.out key.txt hmac.c output.txt
7d1ef72ee877ec646f700288e0693462


Kaeyfile contents:
MHCVGFDC&^$$#@%^MHCVGFDC&^$$#@%^MHCVGFDC&^$$#@%^MHCVGFDC&^$$#@%^

NIS SDES Implementation

#include
#include

typedef unsigned short int uint16 ;
typedef unsigned char uchar;

#define BIT( b, n ) ( ( b >> n ) & 0x01 )

uint16 p10( uint16 );
uint16 p8( uint16 );
uint16 p4( uint16 ) ;
uint16 ip( uint16 );
uint16 ip_inv( uint16 );
uint16 ep( uint16 );
uint16 swap( uint16 );
void print( uint16 );
void genkeys( uint16, uint16*, uint16* );
uint16 encrypt( uint16, uint16, uint16) ;



uint16 S0[4][4] =
{
{ 1, 0, 3, 2 },
{ 3, 2, 1, 0 },
{ 0, 2, 1, 3 },
{ 3, 1, 0, 3 }
};
uint16 S1[4][4] =
{
{ 0, 1, 2, 3 },
{ 2, 0, 1, 3 },
{ 3, 0, 1, 0 },
{ 2, 1, 0, 3 }
};


void dispCorrectUsage()
{
printf( "Incorrect Usage!\n" ) ;
printf( "Correct Usage is: [

]\n" ) ;
printf( "Options:\n\t-e : Encrypt input file\n\t-d: Decrypt Input file\n" ) ;
printf( "If output file is missing, the output is redirected to the standard output\n" ) ;
return;
}

int main ( int argc, char * argv[] )
{
uint16 input,output;
uint16 key,key1,key2;
uint16 tmp;
FILE * ifp;
FILE * ofp;
uchar ch;

key = 0x097;
genkeys( key, &key1, &key2 );

if ( ( argc < 2 ) || ( argc > 4 ) )
{
dispCorrectUsage();
exit( EXIT_FAILURE ) ;
}

ifp = fopen( argv[2], "r+b" ) ;
if ( NULL == ifp )
{
printf( "Unable to open Input file!\n" ) ;
exit( EXIT_FAILURE ) ;
}

if ( 4 == argc )
{
ofp = fopen( argv[3], "w+b" );
if ( NULL == ofp )
{
printf( "Unable to open Output file!\n" ) ;
exit( EXIT_FAILURE ) ;
}
}
else
{
ofp = stdout;
}

genkeys( key, &key1, &key2 );

if ( '-' == argv[1][0] )
{
if ( 'e' == argv[1][1] )
{
while ( 0 != ( fread( &ch, sizeof( uchar ), 1, ifp ) ) )
{
input = ( uint16 ) ch;
output = encrypt( input, key1, key2 ) ;
ch = ( uchar ) output;
fwrite( &ch, sizeof( uchar ), 1, ofp ) ;
}
}
else if ( 'd' == argv[1][1] )
{
while ( 0 != ( fread( &ch, sizeof( uchar ), 1, ifp ) ) )
{
input = ( uint16 ) ch;
output = encrypt( input, key2, key1 ) ;
ch = ( uchar ) output;
fwrite( &ch, sizeof( uchar ), 1, ofp ) ;
}

}
}

return 0;
}

//9876543210 -> 7583609124
uint16 p10 ( uint16 num )
{
uint16 temp = 0x00 ;

temp |= BIT( num, 7 ) << 9;
temp |= BIT( num, 5 ) << 8;
temp |= BIT( num, 8 ) << 7;
temp |= BIT( num, 3 ) << 6;
temp |= BIT( num, 6 ) << 5;
temp |= BIT( num, 0 ) << 4;
temp |= BIT( num, 9 ) << 3;
temp |= BIT( num, 1 ) << 2;
temp |= BIT( num, 2 ) << 1;
temp |= BIT( num, 4 );

return temp ;
}

//9876543210 -> 47362501
uint16 p8( uint16 num )
{
uint16 temp = 0x00 ;

temp |= BIT( num, 4 ) << 7;
temp |= BIT( num, 7 ) << 6;
temp |= BIT( num, 3 ) << 5;
temp |= BIT( num, 6 ) << 4;
temp |= BIT( num, 2 ) << 3;
temp |= BIT( num, 5 ) << 2;
temp |= BIT( num, 0 ) << 1;
temp |= BIT( num, 1 );

return temp;
}

//3210 -> 2013
uint16 p4( uint16 num )
{
uint16 temp = 0x00;

temp |= BIT( num, 2 ) << 3;
temp |= BIT( num, 0 ) << 2;
temp |= BIT( num, 1 ) << 1;
temp |= BIT( num, 3 ) ;

return temp;
}

//76543210 -> 62574031
uint16 ip( uint16 num )
{
uint16 temp = 0x00;

temp |= BIT( num, 6 ) << 7;
temp |= BIT( num, 2 ) << 6;
temp |= BIT( num, 5 ) << 5;
temp |= BIT( num, 7 ) << 4;
temp |= BIT( num, 4 ) << 3;
temp |= BIT( num, 0 ) << 2;
temp |= BIT( num, 3 ) << 1;
temp |= BIT( num, 1 );

return temp;
}


//76543210 -> 47531602
uint16 ip_inv( uint16 num )
{
uint16 temp = 0x00;

temp |= BIT( num, 4 ) << 7;
temp |= BIT( num, 7 ) << 6;
temp |= BIT( num, 5 ) << 5;
temp |= BIT( num, 3 ) << 4;
temp |= BIT( num, 1 ) << 3;
temp |= BIT( num, 6 ) << 2;
temp |= BIT( num, 0 ) << 1;
temp |= BIT( num, 2 );

return temp;
}


//3210 -> 03212103
uint16 ep( uint16 num )
{
uint16 temp = 0x00;

temp |= BIT( num, 0 ) << 7;
temp |= BIT( num, 3 ) << 6;
temp |= BIT( num, 2 ) << 5;
temp |= BIT( num, 1 ) << 4;
temp |= BIT( num, 2 ) << 3;
temp |= BIT( num, 1 ) << 2;
temp |= BIT( num, 0 ) << 1;
temp |= BIT( num, 3 );

return temp;
}

//76543210 -> 32107654
uint16 swap( uint16 num )
{
uint16 temp = 0x00;

temp |= BIT( num, 3 ) << 7;
temp |= BIT( num, 2 ) << 6;
temp |= BIT( num, 1 ) << 5;
temp |= BIT( num, 0 ) << 4;
temp |= BIT( num, 7 ) << 3;
temp |= BIT( num, 6 ) << 2;
temp |= BIT( num, 5 ) << 1;
temp |= BIT( num, 4 );

return temp;
}

// rotate x left y bits, total size is 5 bits
#define ROT_L5(x,y) ((( (x) << (y) ) | ( (x) >> (5-y) )) & 0x1F )
// get the right 5 bits of x
#define RIGHT5(x) ( (x) & 0x1F )
// get the left 5 bits of x
#define LEFT5(x) ( ( (x) >> 5 ) & 0x1F )
// get the right 4 bits of x
#define RIGHT4(x) ( (x) & 0x0F )
// get the left 4 bits of x
#define LEFT4(x) ( ( (x) >> 4 ) & 0x0F )



void print( uint16 num )
{
int i;

for ( i = 9; i >= 0; i-- )
{
printf( "%u", BIT( num, i ) ) ;
}

return;
}

// Generating the two keys
void genkeys( uint16 key, uint16* key1, uint16* key2 )
{
uint16 k1, k2;
uint16 temp;
uint16 left, right;

temp = p10( key ) ;
left = LEFT5( temp ) ;
right = RIGHT5( temp ) ;

left = ROT_L5( left, 1 );
right = ROT_L5( right, 1 );
temp = ( left << 5 ) | right ;
k1 = p8( temp ) ;

left = ROT_L5( left, 2 ) ;
right = ROT_L5( right, 2 ) ;
temp = ( left << 5 ) | right ;
k2 = p8( temp ) ;

*key1 = k1;
*key2 = k2;
return;
}

uint16 F( uint16 input, uint16 key )
{
uint16 answer= 0x00;
uint16 temp;
uint16 left;
uint16 right;
uint16 row, col;

temp = ep( input ) ;
temp = temp ^ key;
left = LEFT4( temp );
right = RIGHT4( temp );

row = ( BIT(left, 3 ) << 1 ) | BIT(left, 0 );
col = ( BIT(left, 2 ) << 1 ) | BIT(left, 1 );
answer = S0[row][col] << 2;

row = ( BIT(right, 3 ) << 1 ) | BIT(right, 0 );
col = ( BIT(right, 2 ) << 1 ) | BIT(right, 1 );
answer |= S1[row][col];

answer = p4( answer ) ;

return answer;
}


// fk(L,R,SK) = ( L ^ F(R,SK),R )
uint16 f_k( uint16 input, uint16 key )
{
uint16 answer;
uint16 left, right;
uint16 temp;

left = LEFT4( input ) ;
right = RIGHT4( input );
temp = left ^ F( right, key );
answer = ( temp << 4 ) | right ;

return answer;
}


uint16 encrypt( uint16 input, uint16 key1, uint16 key2 )
{
uint16 answer;
uint16 temp;

temp = ip( input ) ;
temp = f_k( temp, key1 ) ;
temp = swap( temp ) ;
temp = f_k( temp, key2 ) ;
answer = ip_inv( temp ) ;

return answer;
}


//OUTPUT:

C:\TC\BIN>sdes -e ip.txt op.txt

C:\TC\BIN>sdes -d op.txt
Hello World

ip.txt:-
Hello World

op.txt:-
SĺºgEég«º”

Program for sum of series

//Program to calculate the sum of series

#include
#include
long int factorial(int n);
void main()
{
int n,i;
float s,r;
char c;
clrscr();
repeat : printf("\nYou have this series:- 1/1! + 2/2! + 3/3! + 4/4! ...");
printf("\n\nTo which term you want its sum? ");
scanf("%d",&n);
s=0;
for (i=1;i<=n;i++)
{ s=s+((float)i/(float)factorial(i)); }
printf("\nThe sum of '[%d]' terms is : %f",n,s);
fflush(stdin);
printf ("\n\nDo you want to continue?(y/n):- ");
scanf("%c",&c);
if (c=='y')
goto repeat;
getch();
}

long int factorial(int n)
{
if (n<=1)
return(1);
else
n=n*factorial(n-1);
return(n);
}

Pyramid of nos

//Pyramid of Numbers

#include
#include

int pyramid( int length )
{
clrscr();
int line = 1;
int j = 1, i, k = length;

while( length-- )
{
if( j == 1 )
{
for( i = 1; i <= length + 5; i++ )
printf( "" );
printf( "%d", j++ );printf("\n");
k--;
line++;
}

else if( i % 2 )
{
for( i = 1; i <= length + 5; i++ )
printf( "" );
for( i = 1; i <= line; i++ )
printf( "%d ", ( j++ % 10 ) );
printf( "\n" );
line++;
k--;
}

else
{
for( i = 1; i <= length + 5 ; i++ )
printf( "" );
for( i = 1; i <= line; i++ )
printf( "%d ", ( j++ % 10 ) );
printf( "\n" );
line++;
k--;
}
}

return 0;
}

int main( )
{
clrscr();
int length;

printf( "Enter the list length" );
scanf( "%d", &length );

pyramid( length );
getch( );
return 0;
}

Polynomial Multiplication

//Polynomial Multiplication

#include
#include
#include

typedef struct poly
{
int coeff,expo;
}P;
P p1[10],p2[10],p3[20]={0};
int t1,t2;

void multiply();

void main()
{
int i,ch;
char cho;
clrscr();

printf("Please enter number of terms in p1: ");
scanf("%d",&t1);
printf("\nPlease enter coeff. & expo of terms in p1\n");
for(i=0;i {
scanf("%d%d",&p1[i].coeff,&p1[i].expo);
}
printf("\n\nPlease enter number of terms in p2: ");
scanf("%d",&t2);
printf("\nPlease enter coeff. & expo of terms in p2\n");
for(i=0;i {
scanf("%d%d",&p2[i].coeff,&p2[i].expo);
}

do
{
clrscr();
printf("First polynomial is\n");
for(i=0;i<(t1-1);i++)
{
printf("(%d x^%d) + ",p1[i].coeff,p1[i].expo);
}
printf("(%d x^%d)",p1[i].coeff,p1[i].expo);
printf("\n\nSecond polynomial is\n");
for(i=0;i<(t2-1);i++)
{
printf("(%d x^%d) + ",p2[i].coeff,p2[i].expo);
}
printf("(%d x^%d)",p2[i].coeff,p2[i].expo);

printf("\n\n\tYour choices are:\n");
printf(" \t1:Multiplication\n \t2:Exit\n\n");
printf("\n\nPlease enter your choice: ");
scanf("%d",&ch);

switch(ch)
{
case 1:
multiply();
break;

case 2:
exit();

default:
printf("\n\nInvalid choice");
}
printf("\nPress y to continue and any other key to stop:");
fflush(stdin);
scanf("%c",&ch);
}
while(cho=='y' || cho=='Y');
getch();
}

void multiply()
{
int i=0,j=0,k=0,cnt=0,exp,coef,flag;
for(i=0;i<20;i++)
{
p3[i].coeff=0;
p3[i].expo=0;
}
i=0;
while(i {
j=0;
while(j {
flag=0;
coef=p1[i].coeff*p2[j].coeff;
exp=p1[i].expo+p2[j].expo;
for(cnt=0;cnt {
if(p3[cnt].expo==exp)
{
p3[cnt].coeff=p3[cnt].coeff+coef;
flag=1;
}
}
if(flag==0)
{
p3[k].expo=exp;
p3[k].coeff=coef;
k++;
}
j++;
}
i++;
}
printf("\nMultiplication is \n");
for(i=0;i<(k-1);i++)
{
printf("(%d x^%d) + ",p3[i].coeff,p3[i].expo);
}
printf("(%d x^%d)",p3[i].coeff,p3[i].expo);
}

Vowels Count

//Program to calculate frequency of vowels in a string

#include
#include
void main()
{
int a=0,e=0,i=0,o=0,u=0,sum=0;
char c;
clrscr();
printf("\nEnter string:- ");
printf("\nString will be terminated if you press Ctrl-Z & then ENTER.");
printf("\nSTRING:- ");
while ((c=getchar())!=EOF)
{
if (c=='a'||c=='A')
a=a+1;
if (c=='e'||c=='E')
e=e+1;
if (c=='i'||c=='I')
i=i+1;
if (c=='o'||c=='O')
o=o+1;
if (c=='u'||c=='U')
u=u+1;
}

sum=a+e+i+o+u;
printf("\n\nFrequency of vowel 'a' is %d.",a);
printf("\nFrequency of vowel 'e' is %d.",e);
printf("\nFrequency of vowel 'i' is %d.",i);
printf("\nFrequency of vowel 'o' is %d.",o);
printf("\nFrequency of vowel 'u' is %d.",u);
printf("\nTotal no. of vowels in the text is %d.",sum);
printf("\n\nHAVE A NICE DAY! BYE.");
getch();
}

Matrix Implementation

#include
#include
#include
int a[10][10],b[10][10],x[10][10];
void add()
{
int r,c,i,j,n;
cout<<"ENTER THE ORDER OF MATRIX : ";
cin>>n;
r=n;
c=n;
cout<<"ENTER THE ELEMENTS FOR MATRIX 'A' :"< for(i=0;i {
for(j=0;j {
cin>>a[i][j];
}
}
cout<<"ENTER THE ELEMENTS FOR MATRIX 'B' : "< for(i=0;i {
for(j=0;j {
cin>>b[i][j];
}
}
clrscr();

cout<<"MATRIX 'A' IS "< for(i=0;i {
for(j=0;j {
cout< }
cout< }

cout<<"MATRIX 'B' IS "< for(i=0;i {
for(j=0;j {
cout< }
cout< }
//.....................ADDITION OF MATRIX........................

for(i=0;i {
for(j=0;j {
x[i][j]=a[i][j]+b[i][j];
}
}

cout<<"THE SUM OF TWO ENTERED MATRIX IS "< for(i=0;i {
for(j=0;j {
cout< }
cout< }
}

void multiply()
{
int r1,c1,r2,c2,i,j,k;
clrscr();
cout<<"ENTER THE NO.OF ROWS OF MATRIX (A) : ";
cin>>r1;
cout<<"ENTER THE NO.OF COLOUMS OF MATRIX (A) :";
cin>>c1;
cout<<"ENTER THE ELEMENTS FOR MATRIX (A) :"< for(i=0;i {
for(j=0;j {
cin>>a[i][j];
}
}

cout<<"ENTER THE NO.OF ROWS OF MATRIX (B) : ";
cin>>r2;
cout<<"ENTER THE NO.OF COLOUMS OF MATRIX (B) : ";
cin>>c2;
cout<<"ENTER THE ELEMENTS FOR MATRIX (B) :"< for(i=0;i {
for(j=0;j {
cin>>b[i][j];
}
}

clrscr();
cout<<"MATRIX 'A' IS "< for(i=0;i {
for(j=0;j {
cout< }
cout< }

cout<<"MATRIX 'B' IS "< for(i=0;i {
for(j=0;j {
cout< }
cout< }

if(c1!=r2)
{
cout<<"MULTIPLICATION IS NOT POSSIBLE ";
}
else
{
for(i=0;i {
for(j=0;j {
x[i][j]=0;
for(k=0;k {
x[i][j]=x[i][j]+(a[i][k]*b[k][j]);
}
}
}
}

cout<<"MULTIPLICATION OF TWO MATRIX IS "< for(i=0;i {
for(j=0;j {
cout< }
cout< }
}

void main()
{
clrscr();
while(1)
{
int ch;
cout<<"

";
cout<<"...ENTER YOUR CHOICE........"<cout<<"1. ADDITION OF TWO MATRIX "<cout<<"2. MULTIPLICATION OF TWO MATRIX "<cout<<"3. EXIT "<cin>>ch;
switch(ch)
{
case 1:
add();
break;
case 2:
multiply();
break;
case 3:
exit(0);
default :
cout<<"INVALID CHOICE !! ENTER CORRECT CHOICE";
}
//getch();
}
}

LCM GCD implementation

//Finding LCM and GCD

#include
#include

void main()
{
int a[20],n,i,j,c,max,min;
unsigned long prod;
clrscr();
printf("Enter the no. of entries: ");
scanf("%d",&n);
printf("Enter the entries:");
for(i=0;i {
scanf("%d",&c);
if(c>0)
a[i]=c;
else
{
printf("Invalid Entry");
return;
}
}

max=a[0];
for(i=0;i if(a[i]>=max)
max=a[i];
min=a[0];
for(i=0;i if(a[i] min=a[i];

for(i=0,prod=1;i prod=prod*a[i];

for(i=max;i<=prod;i+=max)
{

c=0;
for(j=0;j if(i%a[j]==0)
c+=1;
if(c==n)
{ printf("The LCM of the nos: %d",i);
break;
}
}

for(i=min;i>0;i--)
{
if (min%i==0)
{
c=0;
for(j=0;j if(a[j]%i==0)
c+=1;
}
if(c==n)
{
printf("The GCD of the nos: %d",i);
break;
}
}
getch();
}

Factorial

//Factorial Function

#include
#include

long int factorial(int n);

void main()
{
int n,i;
float s,r;
char c;
clrscr();
repeat : printf("You have this series:- 1/1! + 2/2! + 3/3! + 4/4!..");
printf("To which term you want its sum? ");
scanf("%d",&n);
s=0;
for (i=1;i<=n;i++)
{
s=s+((float)i/(float)factorial(i));
}
printf("The sum of %d terms is %f",n,s);
fflush(stdin);
printf ("Do you want to continue?(y/n):- ");
scanf("%c",&c);
if (c=='y')
goto repeat;
getch();
}

long int factorial(int n)
{
if (n<=1)
return(1);
else
n=n*factorial(n-1);
return(n);
}

Bubble Sort

//Bsort, bubble sort [array]

#include
#include


void bubble_sort(int a[], int size);

int main(void)
{
clrscr();

int arr[10] = {10, 4, 2, 1, 6, 5, 8, 7, 3, 9};
int i = 0;

printf("before:\n");
for(i = 0; i < 10; i++) printf("%d ", arr[i]);
printf("\n");

bubble_sort(arr, 10);

printf("after:\n");
for(i = 0; i < 10; i++) printf("%d ", arr[i]);
printf("\n");
getch();

return 0;
}

void bubble_sort(int a[], int size)
{
int switched = 1;
int hold = 0;
int i = 0;
int j = 0;

size -= 1;

for(i = 0; i < size && switched; i++)
{
switched = 0;
for(j = 0; j < size - i; j++)
if(a[j] > a[j+1])
{
switched = 1;
hold = a[j];
a[j] = a[j + 1];
a[j + 1] = hold;
}
}

getch();
}

Binary Search

//Binary search [int array]

#include
#include

#define TRUE 0
#define FALSE 1

int main(void)
{
int array[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
int left = 0;
int right = 10;
int middle = 0;
int number = 0;
int bsearch = FALSE;
int i = 0;

printf("ARRAY: ");
for(i = 1; i <= 10; i++)
printf("[%d] ", i);

printf("\nSearch for Number: ");
scanf("%d", &number);

while(bsearch == FALSE && left <= right)
{
middle = (left + right) / 2;
if(number == array[middle])
{
bsearch = TRUE;
printf("** Number Found **\n");
}
else
{
if(number < array[middle]) right = middle - 1;
if(number > array[middle]) left = middle + 1;
}
}

if(bsearch == FALSE)
printf("-- Number Not found --\n");
getch();


return 0;
}

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
*/

NIS RSA Algorithm

#include
#include
#include

void main()
{
clrscr();
unsigned long p,q,n,m,M,e,d,i,C,M1;
cout<<"Enter value of P : ";
cin>>p;
cout<<"Enter value of Q : ";
cin>>q;
n=p*q;
m=(p-1)*(q-1);
for(e=1;e {
if(m%e!=0)
break;
}
d=0;
do
{
d++;
i=(((e*d)-1)%m);
}while(i!=0);
cout<<"e : "< cout<<"d : "< cout<<"Enter value of M : ";
cin>>M;
C=pow(M,e);
C=C%n;
cout<<"Encryption C : "<
M1=pow(C,d);
M1=M1%n;
cout<<"Decryption M1 : "<
getch();
}

NIS Port Scanning

import java.net.*;
import java.io.*;
class Port
{
public static void main(String args[]) throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
String host;
int start,end,avail,unavail,i;
Socket sk;
avail=0;
unavail=0;
System.out.println("Enter the host name : ");
host=br.readLine();
System.out.println("Enter the starting port no : ");
start=Integer.parseInt(br.readLine());
System.out.println("Enter the ending port no : ");
end=Integer.parseInt(br.readLine());
for(i=start;i<=end;i++)
{
System.out.print("Port No. " + i);
try
{
sk=new Socket(host,i);
System.out.println(" : Available");
avail++;
}
catch(Exception E)
{
System.out.println(" : Unavailable");
unavail++;
}
}
System.out.println("Total available port : " + avail);
System.out.println("Total unavailable port : " + unavail);
}
}

NIS Host-IP & Vice versa

import java.io.*;
import java.net.*;

class Host
{
public static void main(String args[]) throws UnknownHostException
{
InetAddress in_obj;
String str;
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
//get name of local computer & initialise the object
in_obj=InetAddress.getLocalHost();
System.out.println("getLocalHost : " + in_obj);
System.out.println();
//get name of local computer
str=in_obj.getHostName();
System.out.println("getHostName : " + str);
System.out.println();
//get canonical host name [local computer]
str=in_obj.getCanonicalHostName();
System.out.println("getCanonicalHostName : " + str);
System.out.println();
//get Host address [local computer]
str=in_obj.getHostAddress();
System.out.println("getHostAddress : " + str);
System.out.println();
//get remote pc info
in_obj=InetAddress.getByName("localhost");
System.out.println(in_obj);
}
}

NIS One time padding

Code :
#include
#include
#include
void main(int argc,char *argv[])
{
FILE *ip, *key, *op;
unsigned char ic, kc, oc;
clrscr();
if(argc!=4)
{
printf("Not valid parameter list...");
}
else
{
fseek(ip,SEEK_SET,0);
ip=fopen(argv[1],"r");
key=fopen(argv[2],"r");
op=fopen(argv[3],"w");
if( (ip==NULL) || (key==NULL) || (op==NULL) )
{
printf("File opening error...");
}
else
{
fread(&ic, sizeof(unsigned char), 1, ip);
do
{
fread(&kc, sizeof(unsigned char), 1, key);
oc=ic ^ kc;
printf("%c",ic);
fwrite(&oc, sizeof(unsigned char), 1, op);
}while(fread(&ic, sizeof(unsigned char), 1, ip));
}
fclose(op);
fclose(key);
fclose(ip);
}
getch();
}

Key File
QWERTYUIOPASDFGHJKLZXCVBNM

NIS Diffe Helman Program

#include
#include
#include

long double mod (long double q,long n)
{
long double rem=0, quo;
quo=q/n;
quo=floor(quo);
rem=q-(quo*n);
return rem;
}

int check_root(long int q,long int a)
{
long double arr[100];
int i,j,k=0,flag=1;
for(i=1;i {
arr[k]=mod(pow(a,i),q);
k++;
}
for(i=0;i {
for(j=0;j {
if ((i!=j) && (arr[i]==arr[j]))
{
flag=0;
break;
}
}
}
return flag;
}
void main()
{
clrscr();
long q,prem_root=2;
long p_A,k_A,p_B,k_B,pub_A,pub_B;
cout<<"Enter prime no : ";
cin>>q;
do
{
prem_root++;
}while(check_root(q,prem_root));

cout<<"Enter private key of A : ";
cin>>p_A;
pub_A=mod(pow(prem_root,p_A),q);

cout<<"Enter private key of B : ";
cin>>p_B;
pub_B=mod(pow(prem_root,p_B),q);

k_A=mod(pow(pub_B,p_A),q);
k_B=mod(pow(pub_A,p_B),q);

cout<<"Public key A : "< cout<<"Public key B : "< if(k_A==k_B)
{
cout<<"Key exchange successful...";
}
else
{
cout<<"Key exchange unsuccessful...";
}
getch();
}