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63 lines
1.4 KiB
Python
63 lines
1.4 KiB
Python
from math import gcd
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def est_premier(n):
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if n < 2:
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return False
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for i in range(2, int(n**0.5) + 1):
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if n % i == 0:
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return False
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return True
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def liste_premier_inf(n):
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return [i for i in range(2, n+1) if est_premier(i)]
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def pgcd(a, b):
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while b:
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a, b = b, a % b
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return a
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def cle_publique_possible(a, b):
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n = a * b
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return [i for i in range(1, n) if pgcd(i, n) == 1]
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def inverse(e, n):
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t, newt = 0, 1
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r, newr = n, e
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while newr != 0:
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quotient = r // newr
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t, newt = newt, t - quotient * newt
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r, newr = newr, r - quotient * newr
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if r > 1:
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raise ValueError("L'inverse modulaire n'existe pas")
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if t < 0:
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t += n
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return t
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def chaine_en_liste(chaine):
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return [ord(c) for c in chaine]
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def chiffre(e, N, liste):
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return [pow(x, e, N) for x in liste]
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def dechiffre(d, N, liste):
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return [pow(x, d, N) for x in liste]
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def liste_en_chaine(liste):
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return ''.join(chr(x) for x in liste)
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a, b = 61, 53
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N = a * b
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phi = (a - 1) * (b - 1)
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e = 17
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d = inverse(e, phi)
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message = "RSA"
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message_code = chaine_en_liste(message)
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message_chiffre = chiffre(e, N, message_code)
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message_dechiffre = dechiffre(d, N, message_chiffre)
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message_final = liste_en_chaine(message_dechiffre)
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print("Message initial:", message)
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print("Message chiffré:", message_chiffre)
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print("Message déchiffré:", message_final)
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