Interfacing changes:

- Split into methods.
    - Added a cli interface with commands 'gen <filename>' to generate keys
      and 'encrypt <message> <publicKey>' to encrypt a message
      to the passed key.
    - Read and save keys.
This commit is contained in:
HeshamTB 2020-04-16 12:35:42 +03:00
parent 4bd8fcf1dd
commit a1e05a572a
Signed by: Hesham
GPG Key ID: 74876157D199B09E

61
rsa.py
View File

@ -5,18 +5,36 @@
import math
import os
import decimal
import sys
def main():
if sys.argv[1] == "gen" and len(sys.argv) == 3:
n ,e ,d = generateKeys()
key = (n, e, d)
keyFileName = sys.argv[2]
try:
saveKeyFile(key, keyFileName)
except IOError:
print("could not write file")
exit(1)
except Exception as ex:
print(ex)
exit(1)
if sys.argv[1] == "encrypt" and len(sys.argv) == 4:
msg = sys.argv[2]
keyName = sys.argv[3]
key = readKeyFile(keyName)
key_public = (key[0], key[1])
msg_encrypted = encrypt(msg, key_public)
def generateKeys(bits=64):
#Primes of size 32 bit random
#resulting in a 64-bit key mod
p = getPrime(32)
print("p: ", p)
q = getPrime(32)
print("q: ", q)
p = getPrime(int(bits/2))
q = getPrime(int(bits/2))
n = p*q
print("n: ", n)
#print("n: ", n)
print("%d bit key" % n.bit_length())
#lamda(n) = LCM(p-1, q-1)
@ -26,23 +44,21 @@ def main():
#lcm = abs((p-1) * (q-1)) / gcd
#print("LCM: ", lcm)
phi = (p-1)*(q-1)
print("phi: ", phi)
#print("phi: ", phi)
#e exponant should be 1 < e < lamda(n) and GCD(e, lamda(n)) = 1 (coprime)
# recommended value is 65,537
e = 65537
d = pow(e,-1,phi)
print("d: ", d)
print("--------------")
print("public key (%d, %d)" % (n,e) )
#print("d: ", d)
print("---------------------------------")
print("public key (%d, %d)" % (n,e))
return n, e, d
msg_text = "Hello"
msg_number_form = int.from_bytes(msg_text.encode(),"little")
print("Message: %s or %d" % (msg_text, msg_number_form))
def encrypt(message, publicKey):
return None
msg_encrypted_number_form = pow(msg_number_form, e, n)
print("Encrypted msg: ", msg_encrypted_number_form)
msg_decrypted_number_form = pow(msg_encrypted_number_form, d, n)
print("Decrypted msg: ", msg_decrypted_number_form)
def decrypt(cipher, privateKey, n):
pass
def getPrime(bits):
while True:
@ -74,6 +90,17 @@ def isPrime(number):
return False
return True
def readKeyFile(keyName):
key = tuple()
with open(keyName, "r") as keyFile:
tempkey = keyFile.readlines()
key = (int(tempkey[0].strip()), int(tempkey[1].strip()), int(tempkey[2].strip()))
return key
def saveKeyFile(key, fileName):
with open(fileName, "w") as keyFile:
keyFile.write("{0}\n{1}\n{2}\n".format(key[0], key[1], key[2]))
if __name__ == "__main__":
main()