Writeup for Crypto Problems in HufuCTF 2020

Writeup for 3 crypto challenges in 虎符CTF 2020 (2020-04-19 09:00 +8h).
- (easy) GM: recover every bit of RSA message by using legendre symbol
- (medium) mceliece: break a Mceliece cryptosystem with small parameters
- (easy) pell: solve specified pell equations.