43 lines
1002 B
Python
43 lines
1002 B
Python
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#!/usr/bin/python
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import math
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def linear_diophantine_equation(a, b):
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if b > a:
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return linear_diophantine_equation(b, a)
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if b == 0:
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return a, 1, 0
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d, x, y = linear_diophantine_equation(b, a % b)
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return (d, y, x - (a // b) * y)
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# c = (a * b) % p
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c = 0x7E65D68F84862CEA3FCC15B966767CCAED530B87FC4061517A1497A03D2
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p = 0xDD8E05FF296C792D2855DB6B5331AF9D112876B41D43F73CEF3AC7425F9
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b = 0x7BBE3A50F28B2BA511A860A0A32AD71D4B5B93A8AE295E83350E68B57E5
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def test_solution(a):
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return (a * b) % p == c
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d, x, y = linear_diophantine_equation(b, p)
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a = y * c
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a += abs(a // p) * p
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solution = hex(a).replace("-", "")[2:]
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# print(p/b)
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while len(solution) != 2*29:
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a += p
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solution = hex(a).replace("-", "")[2:]
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if not test_solution(a):
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print("Not a valid solution")
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exit()
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ascii = ''.join([chr(int(solution[i:i+2],16)) for i in range(0, len(solution), 2)])
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if ascii[0:4] == "HV18":
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print(hex(a))
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print(ascii)
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break
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