现代密码学入门指北

题目在Crypto_in_CTFRu_Men_Zhi_Bei_.pdf中。

 from Crypto.Util.number import bytes_to_long, getPrime
 from secret import flag
 p = getPrime(128)
 q = getPrime(128)
 n = p*q
 e = 65537
 m = bytes_to_long(flag)
 c = pow(m, e, n)
 print(f"n = {n}")
 print(f"p = {p}")
 print(f"q = {q}")
 print(f"c = {c}")
 '''
 n = 
 p = 
 q = 
 c = 
 '''

已知n, p, q, c，求m。 简单的rsa解密即可。

from gmpy2 import *
from Crypto.Util.number import *

n = 
p = 
q = 
c = 
e = 
phi = (p - 1) * (q - 1)
d = invert(e, phi)
M = pow(c, d, n)
print(long_to_bytes(M))