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calculate n,e,d vars from p and q to create an RSA key
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def calculate_rsa_nedpq(p=1090660992520643446103273789680343, q=1162435056374824133712043309728653): | |
""" | |
input large primes p and q, returns the 5 components in a tuple (n, e, d, p, q) which can be used to construct private keys like: | |
RSA.construct() | |
https://crypto.stackexchange.com/questions/19444/rsa-given-q-p-and-e?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa | |
""" | |
def egcd(a, b): | |
x, y, u, v = 0, 1, 1, 0 | |
while a != 0: | |
q, r = b // a, b % a | |
m, n = x - u * q, y - v * q | |
b, a, x, y, u, v = a, r, u, v, m, n | |
gcd = b | |
return gcd, x, y | |
e = 65537 # the same number on generated keys to | |
# compute n | |
n = p * q | |
# Compute phi(n) | |
phi = (p - 1) * (q - 1) | |
# Compute modular inverse of e | |
gcd, a, b = egcd(e, phi) | |
d = a | |
return n, e, d, p, q |
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