Sorry Folks. I commited to a wrong respository. I was testing it against the latest version py3k and I thought i moved it back to my original respository.
Apologize for the trouble and I shall remove it immediately. -- Senthil On Mon, Jan 3, 2011 at 5:47 PM, senthil.kumaran <python-check...@python.org> wrote: > Author: senthil.kumaran > Date: Mon Jan 3 10:47:09 2011 > New Revision: 87677 > > Log: > py3k implmentation of RSA algorithm, > > > > Added: > python/branches/py3k/py3rsa.py (contents, props changed) > > Added: python/branches/py3k/py3rsa.py > ============================================================================== > --- (empty file) > +++ python/branches/py3k/py3rsa.py Mon Jan 3 10:47:09 2011 > @@ -0,0 +1,181 @@ > +# Copyright (c) 2010 Russell Dias > +# Licensed under the MIT licence. > +# http://www.inversezen.com > +# > +# This is an implementation of the RSA public key > +# encryption written in Python by Russell Dias > + > +__author__ = 'Russell Dias // inversezen.com' > +# Py3k port done by Senthil (sent...@uthcode.com) > +__date__ = '05/12/2010' > +__version__ = '0.0.1' > + > +import random > +from math import log > + > +def gcd(u, v): > + """ The Greatest Common Divisor, returns > + the largest positive integer that divides > + u with v without a remainder. > + """ > + while v: > + u, v = u, u % v > + return u > + > +def eec(u, v): > + """ The Extended Eculidean Algorithm > + For u and v this algorithm finds (u1, u2, u3) > + such that uu1 + vu2 = u3 = gcd(u, v) > + > + We also use auxiliary vectors (v1, v2, v3) and > + (tmp1, tmp2, tmp3) > + """ > + (u1, u2, u3) = (1, 0, u) > + (v1, v2, v3) = (0, 1, v) > + while (v3 != 0): > + quotient = u3 // v3 > + tmp1 = u1 - quotient * v1 > + tmp2 = u2 - quotient * v2 > + tmp3 = u3 - quotient * v3 > + (u1, u2, u3) = (v1, v2, v3) > + (v1, v2, v3) = (tmp1, tmp2, tmp3) > + return u3, u1, u2 > + > +def stringEncode(string): > + """ Brandon Sterne's algorithm to convert > + string to long > + """ > + message = 0 > + messageCount = len(string) - 1 > + > + for letter in string: > + message += (256**messageCount) * ord(letter) > + messageCount -= 1 > + return message > + > +def stringDecode(number): > + """ Convert long back to string > + """ > + > + letters = [] > + text = '' > + integer = int(log(number, 256)) > + > + while(integer >= 0): > + letter = number // (256**integer) > + letters.append(chr(letter)) > + number -= letter * (256**integer) > + integer -= 1 > + for char in letters: > + text += char > + > + return text > + > +def split_to_odd(n): > + """ Return values 2 ^ k, such that 2^k*q = n; > + or an odd integer to test for primiality > + Let n be an odd prime. Then n-1 is even, > + where k is a positive integer. > + """ > + k = 0 > + while (n > 0) and (n % 2 == 0): > + k += 1 > + n >>= 1 > + return (k, n) > + > +def prime(a, q, k, n): > + if pow(a, q, n) == 1: > + return True > + elif (n - 1) in [pow(a, q*(2**j), n) for j in range(k)]: > + return True > + else: > + return False > + > +def miller_rabin(n, trials): > + """ > + There is still a small chance that n will return a > + false positive. To reduce risk, it is recommended to use > + more trials. > + """ > + # 2^k * q = n - 1; q is an odd int > + (k, q) = split_to_odd(n - 1) > + > + for trial in range(trials): > + a = random.randint(2, n-1) > + if not prime(a, q, k, n): > + return False > + return True > + > +def get_prime(k): > + """ Generate prime of size k bits, with 50 tests > + to ensure accuracy. > + """ > + prime = 0 > + while (prime == 0): > + prime = random.randrange(pow(2,k//2-1) + 1, pow(2, k//2), 2) > + if not miller_rabin(prime, 50): > + prime = 0 > + return prime > + > +def modular_inverse(a, m): > + """ To calculate the decryption exponent such that > + (d * e) mod phi(N) = 1 OR g == 1 in our implementation. > + Where m is Phi(n) (PHI = (p-1) * (q-1) ) > + > + s % m or d (decryption exponent) is the multiplicative inverse of > + the encryption exponent e. > + """ > + g, s, t = eec(a, m) > + if g == 1: > + return s % m > + else: > + return None > + > +def key_gen(bits): > + """ The public encryption exponent e, > + can be an artibrary prime number. > + > + Obviously, the higher the number, > + the more secure the key pairs are. > + """ > + e = 17 > + p = get_prime(bits) > + q = get_prime(bits) > + d = modular_inverse(e, (p-1)*(q-1)) > + return p*q,d,e > + > +def write_to_file(e, d, n): > + """ Write our public and private keys to file > + """ > + public = open("publicKey", "w") > + public.write(str(e)) > + public.write("\n") > + public.write(str(n)) > + public.close() > + > + private = open("privateKey", "w") > + private.write(str(d)) > + private.write("\n") > + private.write(str(n)) > + private.close() > + > + > +if __name__ == '__main__': > + bits = input("Enter the size of your key pairs, in bits: ") > + > + n, d, e = key_gen(int(bits)) > + > + #Write keys to file > + write_to_file(e, d, n) > + > + print("Your keys pairs have been saved to file") > + > + m = input("Enter the message you would like to encrypt: ") > + > + m = stringEncode(m) > + encrypted = pow(m, e, n) > + > + print("Your encrypted message is: %s" % encrypted) > + decrypted = pow(encrypted, d, n) > + message = stringDecode(decrypted) > + print("You message decrypted is: %s" % message) > _______________________________________________ > Python-checkins mailing list > python-check...@python.org > http://mail.python.org/mailman/listinfo/python-checkins > -- Senthil _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
