adds rsa and diffie helman

ciphers/utils.py

@@ -1,10 +1,30 @@
+import numpy as np
+
+
 def int_to_bin(number: int, block_size=8) -> str:
     binary = bin(number)[2:]
     return '0' * (block_size - len(binary)) + binary
 
 
 def char_2_num(letter: str) -> int:
-    return ord(letter) - ord('a')
+    return ord(letter.lower()) - ord('a')
+
+
+def token_2_num(word: str) -> list:
+    return [char_2_num(letter) for letter in word]
+
+
+def to_val(word: str, base: int = 26) -> int:
+    value = 0
+    for index, letter in enumerate(word[::-1]):
+        value += char_2_num(letter) * pow(base, index)
+    return value
+
+
+def incidence_of_coincidence(frequency: list) -> float:
+    f = np.array(frequency)
+    N = f.sum()
+    return (f * (f - 1)).sum() / (N * (N - 1))
 
 
 def num_2_char(number: int) -> str:

diffie-hellman/diffie_hellman.py

@@ -0,0 +1,17 @@
+from mathematics import *
+
+
+a = 2
+p = 11
+
+# eve
+X_1 = 6
+Y_1 = 9
+
+# bob
+Y_2 = 3
+X_2 = discrete_log(3, 2, 11)
+
+K = a ** (X_1 * X_2) % 11
+print(K)
+

diffie-hellman/discrete-log-brute-force.py

@@ -0,0 +1,12 @@
+from mathematics import *
+import pprint
+import pandas
+
+a = 2
+b = 7
+m = 9
+
+# table = pandas.DataFrame(discrete_log_table(7))
+# print(table)
+
+print(discrete_log(9, 2, 11))

mathematics/arithmetic.py

@@ -150,6 +150,14 @@ def totient(number: int) -> int:
     return count
 
 
+def relatively_prime_numbers(n):
+    numbers = []
+    for i in range(1, n):
+        if relatively_prime(i, n):
+            numbers.append(i)
+    return numbers
+
+
 def crt_representation(number: int, crt: tuple) -> list:
     result = []
     for mod in crt:
@@ -177,3 +185,19 @@ def is_product_of_2_primes(number: int) -> bool:
             if is_prime(i) and is_prime(quotient):
                 return True
     return False
+
+
+def discrete_log_table(number: int) -> list:
+    table = []
+    for i in range(1, number):
+        row = []
+        for j in range(1, number):
+            row.append(pow(i, j, number))
+        table.append(row)
+    return table
+
+
+def discrete_log(n, b, m):
+    for i in range(m):
+        if pow(b, i, m) == n:
+            return i

requirements.txt

@@ -1 +1,2 @@
 numpy
+pandas

rsa/rsa_sample.py

@@ -0,0 +1,25 @@
+from mathematics import *
+import random
+
+
+p, q = 5, 11
+n = p * q
+print('n:', n)
+phi_n = totient(n)
+print('totient:', phi_n)
+phi_n_list = relatively_prime_numbers(phi_n)
+print(phi_n_list)
+# e = phi_n_list[random.randint(0, len(phi_n_list))]
+e = 17
+print('e:', e)
+d = multiplicative_inverse(e, phi_n)
+print('d:', d)
+
+# m = random.randint(0, n)
+m = 8
+c = pow(m, e, n)
+print('plaintext:', m)
+print('ciphertext:', c)
+
+p = pow(c, d, n)
+print('decrypted:', p)

test.py

@@ -1,13 +1,8 @@
 from mathematics import *
 from ciphers import *
+from ciphers.utils import *
 import numpy as np
+import math
+import tensorflow
 
-plaintext = 'meetmelater'
-
-caesar_cipher = CaesarShiftCipher(shift=23)
-permutation_cipher = PermutationCipher(key=[3, 5, 2, 4, 1])
-
-ciphertext = caesar_cipher.encrypt(plaintext)
-
-print(ciphertext)
-print(permutation_cipher.encrypt(ciphertext))
+print(tensorflow.version.VERSION)