#!/usr/bin/env python3

# https://stackoverflow.com/a/18266970

from Crypto.PublicKey import RSA
from struct import pack
from hashlib import sha3_512
from sys import argv
from base64 import b64decode, b64encode


class PRNG(object):
    def __init__(self, seed):
        self.index = 0
        self.seed = sha3_512(seed).digest()
        self.buffer = b""

    def __call__(self, n):
        while len(self.buffer) < n:
            self.buffer += sha3_512(self.seed + pack("<d", self.index)).digest()
            self.index += 1

        result, self.buffer = self.buffer[:n], self.buffer[n:]
        return result


bits = int(argv[1])
secret = b64decode(argv[2])
key = RSA.generate(bits, randfunc=PRNG(secret))

print(
    b64encode(key.export_key('DER')).decode()
)