gui_nofilehandling.py

from Tkinter import *
import random
import math

letters={chr(i):i for i in range(256)}

numbers={}
for letter,num in letters.items():
    numbers[num]=letter
   

def exponentMod(A,B,C) :
 
    if (A == 0):
        return 0

    if (B == 0):
        return 1
 
    if (B % 2 == 0):
        y = exponentMod(A, B / 2, C)
        y = (y * y) % C
 
    else:
        y = A % C
        y = (y * exponentMod(A, B - 1, C) % C) % C 
   
    return (int)((y + C) % C) 

def isPrime(n):
    for i in range(2,int(n**0.5)+1):
        if n%i==0:
            return False
    return True


def gcd(x,y): 
    if(y==0): 
        return x 
    else: 
        return gcd(y,x%y)


def gen_public_key(n,phi):
	list_random_e=[i for i in range(1,phi) if (n%i!=0 and gcd(i,phi) ==1)]
	e=random.choice(list_random_e)
	return (n,e)

def gen_private_key(n,phi,e):
	list_random_k=[i for i in range(1,phi) if (((i*phi)+1)%e ==0)]
	k=random.choice(list_random_k)
	d=((k*phi)+1)/e
	return (n,d)
'''
f=open("toBeEncrypted.txt","r")
z=f.read()
f.close()		
'''
primes=[i for i in range(26,1000) if isPrime(i)]
p=random.choice(primes)
primes.remove(p)
q=random.choice(primes)

n=p*q
phi=(p-1)*(q-1)

public_key=gen_public_key(n,phi)
print "public key (n,e) : ",public_key
private_key=gen_private_key(n,phi,public_key[1])
print "private key (n,d) ",private_key


def change(c):
	d=""
	while(c>0):
		digit=c%10
		e=random.randint(0,9)
		d+=str(e)+str(digit)   #adding random then actual digit , on reversing we get actual digit followed by random no
		c=c/10
	return d[::-1]
	


def Encrypt():
	tog=""
	for i in entryvalue.get():
		c=exponentMod(letters[i],public_key[1],n)
		s=change(c)
		s=s+" "
		tog=tog+s
	listbox.insert(0,tog)


def changeback(i):
	print i
	original=""
	for n in range(0,len(i)):
		if(n%2==0):
			original+=i[n]
		
	return int(original)

def Decrypt():
	list_of=entryvalue2.get().split()
	decrypted_pwd=""
	for i in list_of:
		cipher=changeback(i)
		decryp=exponentMod(cipher,private_key[1],n)
		dmsg=numbers[decryp]
		decrypted_pwd=decrypted_pwd+dmsg
	listbox2.insert(0,decrypted_pwd)

	


root = Tk()    
# GUI title                
root.title('RSA ENCRYPTOR AND DECRYPTOR')   

# ******************plaintext input*****************
l = Label(root,text='Input the plaintext')
l.pack() 

# input plaintext
entryvalue = Entry(root) 
entryvalue.pack()

# click the Encrypt button
button = Button(root,text="Encrypt",command=Encrypt) 
button.pack()

# show the ciphertext info.
show = Label(root,text='Show Ciphertext:')
show.pack() 
listbox  = Listbox(root,height = 10, width = 300)        
listbox.pack() 
# ******************plaintext input ending*****************





# ******************ciphertext input*****************
label = Label(root,text='Input the ciphertext')
label.pack() 

# input ciphertext
entryvalue2 = Entry(root) 
entryvalue2.pack()

# click the Decrypt button
button2 = Button(root,text="Decrypt",command=Decrypt) 
button2.pack()

# show the plaintext info.
show2 = Label(root,text='Show Plaintext:')
show2.pack() 
listbox2  = Listbox(root,height = 10, width = 300)         
listbox2.pack() 
# ******************ciphertext input ending*****************


root.mainloop()