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List of Practicals and Projects to be completed

For

.'ec/ *CS#, t/ Sem. *6rd )ear,

!-1 8rite a pro+ram to con9ert decimal number into binary number in clan+ua+e.

!-2 8rite a pro+ram to find (C5 of +i9en numbers in C lan+ua+e.

!-6 8rite a pro+ram to find +eneral and particular solution.

!- 8rite a pro+ram to implement #uclidean al+orit/m in C lan+ua+e.

!im -; 8rite a pro+ram to implement # 8rite a pro+ram to implement !dditi9e4 multiplicati9e and affine

cip/er in C lan+ua+e

!im-? 8rite a pro+ram to find multiplicati9e in9erse in C lan+ua+e.

!im-10 8rite a pro+ram to mplement %ail fence encryption in C lan+ua+e.

!im-11 8rite a pro+ram to mplement %S! al+orit/m in C lan+ua+e.

!im-12 8rite a pro+ram in C to implement 5#S al+orit/m in C lan+ua+e.

!im-16 8rite a pro+ram to mplement "uffman codin+ in C lan+ua+e.

*5!)!N!N5,

!sst. Prof. *CS#,

"%'4 "amidpur4 5el/i-6"$5


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$@#C'7# of NETWORK SECURIT !"#

$% The &'r&ose of this co'rse is to be able to e(&lain, confi)'re,*erif+, and tro'bleshoot networks sec'rit+ &robles at anintroductory le*el%

-% To learn *ario's ethods of encr+&tion as well as decr+&tion

thro')h &ractical &ro)rain) in order to i&leent in

inforation and network sec'rit+%.% To create &assword and cate)ori/ed in stron) or weak

&assword%0% To 9erify that a co&'ter network has been &ro&erl+ sec'red


4/34

Aim- Write a program to convert decimal number into binarynumber in c language.

Step:-#include#includeint dectobin(int,int*);void arrrev(int*,int);void main(){

clrscr();int num,num!,arr"$%,arr!"$%,i,temp,temp!,s,s!;

print&('n+ S+ /0123 4.:');scan&('5d',6num);print&('n+ S04/ /0123 4.:');scan&('5d',6num!);s7dectobin(num,arr);s!7dectobin(num!,arr!);print&('nn+8 92 =23+ 4 5d S:',num);&or(i7$;i


5/34

arr"A%7arr"B%; arr"B%7temp;@

@


6/34

Aim:- Write a program to find GCD of given numbers in Clanguage.Steps:-

#include#includeint ?cd(int,int);

int n,mat"$$%,i,r,r,r!,F,a,b,m;void main(){

clrscr();print&('n 8oC manG number u Cant to input to &ind the H0/7');

scan&('5d',6n);print&('n enter the numbers');

&or(i7$;i


7/34

Aim:- Write a program to encrypt a message in C language.Steps:

#include

#include#include#include

void encrGpt(char *ms?,int B)EEvoid main(){int len?th,*arr,i;len?th7strlen(ms?);

arr7(int* )malloc(len?th*siIeo&(int));&or(i7$;i


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decrGpt(ms?,B);print&('nn +8 /0N+/ 1SS2H S:5s',ms?);

?etch();

@


9/34

Aim:- Write a program to find general and particular solution.

Steps:-

#include#includevoid main(){

int a,b,c,r,r!,r,F,F,d,r,rM,rO,s7$,t7$,s7,s!7$,t7$,t!7,P$,G$,P,G;clrscr();print&('n enter the value o& a7');scan&('5d',6a);print&('n enter the value o& b7');

scan&('5d',6b);print&('n enter the value o& c 7');scan&('5d',6c);r7a;r!7b;F7$;Chile(r!>$){

F7rEr!;r7r-F*r!;r7r!;r!7r;

@d7r;i&(c5d77$){

print&('nn it has a solution');r7aEd;rM7bEd;Chile(rM>$){

F7rErM;

rO7r-F*rM;r7rM;rM7rO;s7s-F*s!;t7t-F*t!;s7s!;s!7s;t7t!;t!7t;

@print&('nn value o& s75d ,t75d',s,t);P$7(cEd)*s;G$7(cEd)*t;

print&('nnn particular solution is ?iven bG P$75d , G$75d',P$,G$);print&('nnn?eneral solution:n');print&('nnn P 7 5d 5dB',P$,bEd);print&('nnn G 7 5d - 5dB',G$,aEd);


10/34

print&('t(Chere B is an inte?er)');@elseprint&('n n it has no solution');

?etch();@


11/34

Aim:- Write a program to implement Additive, multiplicativeand affine cipher in C language.Steps:-

#include#include#include#includevoid addencrGpt(char *mms?,int B){

int len,*arr,i;len7strlen(mms?);arr7(int *)malloc(len*siIeo&(int));

&or(i7$;i


12/34

{int len,*arr,i,temp;len7strlen(mms?);arr7(int *)malloc(len*siIeo&(int));

&or(i7$;i


13/34

print&('nn + Q:'); scan&('5d',6B); addencrGpt(ms?,B); print&('nn +8 0N+/ 1SS2H S:5s',ms?);

adddecrGpt(ms?,B); print&('nn +8 /0N+/ 1SS2H S:5s',ms?); breaB;case !:print&('nn 1+N302+= 0N8'); print&('nn + Q:'); scan&('5d',6B); mulencrGpt(ms?,B); print&('nn +8 0N+/ 1SS2H S:5s',ms?); i&(?cd(B,!L)77)

{ r7!L;r!7B;t7$;t!7;Chile(r!D7$){

F7rEr!;r7r5r!;t7t-F*t!;

r7r!;r!7r;t7t!;t!7t;

@

Chile(t


14/34

#include#include#include

void addencrGpt(char *ms?,int B)

{int len?th,*mat,A;len?th7strlen(ms?);mat7(int* )malloc(len?th*siIeo&(int));&or(A7$;A


15/34

mat"A%7ms?"A%-LO;ms?"A%7(mat"A%*B)5!LJK;i&(((mat"A%*B)5!L)


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r7!L,r!7B;Chile(r!>$){F7rEr!;

r7r-F*r!;r7r!,r!7r;t7t-F*t!;t7t!,t!7t;@

i&(r77){Chile(t


18/34

Aim:- Write a program to implement !uclidean algorithm in Clanguage.Steps:-#include

#includevoid main(){

clrscr();int n,n!,r,r!,F,r;print&('n+ S+ 19:');scan&('5d',6n);print&('n+ S04/ 19:');scan&('5d',6n!);

i&(n>7$ 66 n!>7$){r7n;r!7n!;print&('ntt!t');Chile(r!D7$){ r7r5r!; F7rEr!; print&('nn5dt5dt5dt5d',F,r,r!,r); r7r!;

r!7r;@print&('nn-t5dt5dt-',r,r!);print&('nn H0/(5d,5d)75d',n,n!,r);

@elseprint&('n=23/ + + 2H2');?etch();

@


19/34

Aim:- Write a program to implement !"tended !uclidean algorithmin C language.Steps:-

#include#includevoid main(){

clrscr();int n,n!,r,r!,r,F,s7,s!7$,s,t7$,t!7,t;print&('n+ S+ 19:');scan&('5d',6n);print&('n+ S04/ 19:');

scan&('5d',6n!);i&(n>7$ 66 n!>7$){

print&('ntt!ttStS!tSt+t+!t+');r7n;r!7n!;Chile(r!D7$){

r7r5r!;F7rEr!;

s7s-F*s!;t7t-F*t!;print&('nn5dt5dt5dt5dt5dt5dt5dt5dt5dt

5d',F,r,r!,r,s,s!,s,t,t!,t);r7r!;r!7r;s7s!;s!7s;t7t!;

t!7t;@print&('nn-t5dt5dt-t5dt5dt-t5dt5dt-',r,r!,s,s!,t,t!);print&('nnH0/(5d,5d)75d',n,n!,r);

@elseprint&('n=23/ + + 2H2');

?etch(); @


20/34

Aim- Write a program to create pass#ord and find #hether givenpass#ord is strong or #ea$.Steps:-#include

#include#includevoid verGCeaB(char*,char*,int);void main(){

char un"O%,psC"O%,psCC"O%;int len;clrscr();a:print&('n+ S21:');

&&lush(stdin);?ets(un);print&('n+ N2SS4/(M-O):');&&lush(stdin);?ets(psC);len7strlen(psC);i&(len>O){

print&('n3H+8 4=ST N32S +n');?oto a;

@print&('n+ N2SS4/:');&&lush(stdin);?ets(psCC);i&(strcmp(psC,psCC)D7$){

print&('n+N 1S12+08 + S21 2/N2SS4/n');

?oto a;

@print&('nS21:');puts(un);print&('nN2SS4/:');puts(psC);

EEprint&('5d',len);verGCeaB(psC,un,len);?etch();

@void verGCeaB(char *ppsC,char *uun,int llen){

int &la?7$;


21/34

i&(strcmp(ppsC,uun)77$)&la?7;i&(llen


22/34

Aim- Write a program to find multiplicative inverse in C language.Steps:-#include

#includeint ?cd(int,int);void main(){

clrscr();int n,a,r,r!,F,r,t,t!,t;print&('na * b 04+4 (mod B)');print&('nnnter B:');scan&('5d',6n);

print&('nnnter a($


23/34

@int ?cd(int P,int G){

int i,?,n;

i&(P


24/34

Aim:- Write a program to %mplement &SA algorithm in Clanguage.Steps:-

E* 0 pro?ram &or the mplementation 4& S2 2l?orithm *E

#include#include

int phi,1,n,e,d,0,32H;

int checB(){

int i;&or(i7;e5i77$ 66 phi5i77$;i!){32H 7 ;return;@32H 7 $;@

void encrGpt()

{int i;0 7 ;&or(i7$;i< e;i)070*15n;0 7 05n;print&('ntncrGpted BeGCord : 5d',0);@

void decrGpt(){int i;1 7 ;&or(i7$;i< d;i)171*05n;1 7 15n;print&('nt/ecrGpted BeGCord : 5d',1);@

void main(){int p,F,s;


25/34

clrscr();print&('nter +Co elativelG Nrime umberst: ');scan&('5d5d',6p,6F);n 7 p*F;

phi7(p-)*(F-);print&('nt(n)t7 5d',phi);do{print&('nnnter et: ');scan&('5d',6e);checB();@Chile(32H77);d 7 ;

do{s 7 (d*e)5phi;d;@Chile(sD7);d 7 d-;print&('ntNublic QeGt: {5d,5d@',e,n);print&('ntNrivate QeGt: {5d,5d@',d,n);print&('nnnter +he Nlain +ePtt: ');scan&('5d',61);

encrGpt();print&('nnnter the 0ipher tePtt: ');scan&('5d',60);decrGpt();?etch();@


26/34

Aim:- Write a program in C to implement D!S algorithm in Clanguage.

Steps:# include # include # include # include # include int BeG"LM%7{ $,$,$,,$,$,,, $,$,,,$,,$,$,

$,,$,,$,,,, $,,,,,$,$,, ,$,$,,,$,,, ,$,,,,,$,$, ,,$,,,,,, ,,,,$,$,$, @;class /es{ public:

int BeGi"L%"MV%, total"LM%, le&t"!%, ri?ht"!%, cB"!V%, dB"!V%, ePpansion"MV%, I"MV%, Por"MV%,

sub"!%, p"!%, Por!"!%, temp"LM%, pc"OL%, ip"LM%, inv"V%"V%;

char &inal"$$$%;

void N(); void Nerm0hoice(); void Nerm0hoice!(); void Ppansion();


27/34

void inverse(); void PorWtCo(); void PorWone(int); void PorWone/(int);

void substitution(); void permutation(); void BeG?en(); char * ncrGpt(char *); char * /ecrGpt(char *);@;void /es::N() EEnitial Nermutation{ int B7OV,i;

&or(i7$;i$) B7B-V; else B7BOV; @ B7OK; &or( i7!;i$) B7B-V; else B7BOV; @@void /es::Nerm0hoice() EENermutation 0hoice-{ int B7OK,i; &or(i7$;i

pc"i%7BeG"B-%; i&(B-V>$) B7B-V; else B7BOK; @ B7L; &or( i7!V;i$) B7B-V;

else B7BOO; @ B7!V; &or(i7O!;i


28/34

{ pc"i%7BeG"B-%; B7B-V; @

@


29/34

Aim- Write a program to %mplement &ail fence encryption in Clanguage.Steps:-

#include#includevoid main(){ int i7$,B7$,A7$,l;

char a"!$%,b"$%,c"!$%; clrscr(); print&('nenter plain tePt:n '); ?ets(a); Chile(a"i%D7R$R)

{ i&(a"i%D7R R) B; @ i7$; Chile(a"i%D7R$R) { i&(a"i%D7R R) c"A%7a"i%; i;

@ c"A%7R$R;EE puts(c); A7$;l7$; &or(i7$;i


30/34

char up"!$%; int len,i7$,A7$; clrscr(); print&('nenter the tePt &or encrGption:');

?ets(tePt); Chile(tePt"i%D7R$R) { i&(i5!77$)

{ up"A%7tePt"i%; A;@i;

@ up"A%7R$R; puts(up); ?etch();

@


31/34


32/34

int i7, A7!; E* ?nome sort *E int *a 7 heap->h;

Chile(i < heap->n) { E* smaller values are Bept at the end *E

i& ( heap->&"a"i-%% >7 heap->&"a"i%% ) { i 7 A; A; @ else { sCapW(i-, i); i--; i 7 (i77$) Y A : i; @ @@

#unde& sCapW static void WheapWadd(heapWt *heap, int c){ i& ( (heap->n ) > heap->s ) { heap->h 7 realloc(heap->h, heap->s heap->cs); heap->s 7 heap->cs; @ heap->h"heap->n% 7 c; heap->n;

WheapWsort(heap);@ static int WheapWremove(heapWt *heap){ i& ( heap->n > $ ) { heap->n--; return heap->h"heap->n%; @

return -;@ E* hu&&mann code ?enerator *Ehu&&codeWt **createWhu&&manWcodes(lon? *&reFs){ hu&&codeWt **codes; heapWt *heap; lon? e&reFs"9+S*!%;

int preds"9+S*!%; int i, ePt&79+S; int r, r!;


33/34

memcpG(e&reFs, &reFs, siIeo&(lon?)*9+S); memset(6e&reFs"9+S%, $, siIeo&(lon?)*9+S);

heap 7 WheapWcreate(9+S*!, e&reFs);

i& ( heap 77 33 ) return 33;

&or(i7$; i < 9+S; i) i& ( e&reFs"i% > $ ) WheapWadd(heap, i);

Chile( heap->n > ) { r 7 WheapWremove(heap); r! 7 WheapWremove(heap); e&reFs"ePt&% 7 e&reFs"r% e&reFs"r!%;

WheapWadd(heap, ePt&); preds"r% 7 ePt&; preds"r!% 7 -ePt&; ePt&; @ r 7 WheapWremove(heap); preds"r% 7 r; WheapWdestroG(heap);

codes 7 malloc(siIeo&(hu&&codeWt *)*9+S);

int bc, bn, iP;

&or(i7$; i < 9+S; i) { bc7$; bn7$; i& ( e&reFs"i% 77 $ ) { codes"i% 7 33; continue; @ iP 7 i; Chile( abs(preds"iP%) D7 iP ) { bc Z7 ((preds"iP% >7 $) Y : $ ) code 7 bc; @ return codes;@

void &reeWhu&&manWcodes(hu&&codeWt **c){ int i;


34/34

&or(i7$; i < 9+S; i) &ree(c"i%); &ree(c);@

#de&ine 12U9+SN04/ $$ void inttobits(int c, int n, char *s){ s"n% 7 $; Chile(n > $) { s"n-% 7 (c5!) R$R; c >>7 ; n--; @

@ const char *test 7 'this is an ePample &or hu&&man encodin?'; int main(){ hu&&codeWt **r; int i; char strbit"12U9+SN04/%; const char *p;

lon? &reFs"9+S%;

memset(&reFs, $, siIeo& &reFs);

p 7 test; Chile(*p D7 R$R) &reFs"*p%;

r 7 createWhu&&manWcodes(&reFs);

&or(i7$; i < 9+S; i) { i& ( r"i% D7 33 ) { inttobits(r"i%->code, r"i%->nbits, strbit); print&('5c (5d) 5sn', i, r"i%->code, strbit); @ @

&reeWhu&&manWcodes(r);

return $;@

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Lab Manual Network security