First commit

lib/rsa.py

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+# Python RSA implementation
+
+import random
+import sys
+
+import lib.arithmetics as arithm
+import lib.miller_rabin as miller
+
+def get_p_and_q(n: int) -> (int, int):
+    # Get two random prime numbers
+    p = miller.get_random_prime(n)
+    q = miller.get_random_prime(n)
+    # Ensure the two numbers are differents
+    while p == q:
+        q = get_random_prime(n)
+    return (p, q)
+
+def get_keys(l: int) -> int:
+    p, q = get_p_and_q(l // 2)
+    n = p * q 
+    phy_n = (p - 1) * (q - 1)
+    e = 65537
+    while arithm.gcd(e, phy_n) != 1:
+        p, q = get_p_and_q(l // 2)
+        n = p * q 
+        phy_n = (p - 1) * (q - 1)
+    d = arithm.mod_inverse(e, phy_n)
+    return (e, d, n)
+
+def encrypt(m: int, e: int, n: int) -> int:
+    return arithm.modpow(m, e, n)
+
+def decrypt(c: int, d: int, n: int) -> int:
+    return arithm.modpow(c, d, n)
+