ALL the CTFS of Crypto2025 finally

crypto-asimmetric/inferious_prime/test.py

@@ -0,0 +1,30 @@
+#!/usr/bin/env python3
+
+from Cryptodome.PublicKey import RSA
+
+
+#kth root of the number n
+def iroot(k, n):
+    u, s = n, n+1
+    while u < s:
+        s = u
+        t = (k-1) * s + n // pow(s, k-1)
+        u = t // k
+    return s
+
+if __name__ == '__main__':
+
+    e = 3
+    # d = rsa_keypair.d
+    n = 388435672474892257936058543724812684332943095105091384265939
+    m = b'A'*8
+    m_int = int.from_bytes(m,byteorder='big')
+
+    c = pow(m_int,e,n)
+
+    decrypted_int = iroot(e, c)
+    print(decrypted_int)
+    print(decrypted_int.to_bytes(decrypted_int.bit_length() // 8 +1, byteorder='big').decode())
+
+    dec = pow(c, 1/3)
+    print(dec)