Bindings to 'smcrypto' < https://github.com/zhuobie/smcrypto>: a 'Rust' implementation of China's Standards of Encryption Algorithms, which is usually called 'ShangMi(SM)' algorithms. It contains 'SM3' message digest algorithm, 'SM2' asymmetric encryption algorithm and 'SM4' symmetric encryption algorithm. Users can do message hash, encrypt/decrypt, sign/verify, key exchange and more.