fn main() {
    use rsa::pkcs8::EncodePublicKey;
    use rsa::sha2::Digest;
    use rsa::RsaPrivateKey;
    use rsa8 as rsa;

    let mut rng = rand::thread_rng();
    let bits = 2048;
    let data = vec![0_u8; 100];

    let private_key = RsaPrivateKey::new(&mut rng, bits).expect("failed to generate a key");
    let public_key = private_key.to_public_key();

    let mut h = rsa::sha2::Sha256::default();
    h.update(&data);
    let hash = h.finalize();

    let pss = rsa::Pss::new::<rsa::sha2::Sha256>();
    let sig = private_key.sign_with_rng(&mut rng, pss, &hash).unwrap();

    let pem = public_key
        .to_public_key_pem(rsa::pkcs8::LineEnding::LF)
        .unwrap();

    dbg!(&pem, hex::encode(hash), hex::encode(&sig));
    t_rsa8(&pem, &hash, &sig);
    t_rsa9(&pem, &hash, &sig);
}

fn t_rsa8(public_key_pem: &str, hashed_data: &[u8], sig: &[u8]) {
    use rsa8::pkcs8::DecodePublicKey;
    use rsa8::{PublicKey, RsaPublicKey};

    println!("START RSA-8");

    let pk = RsaPublicKey::from_public_key_pem(public_key_pem).expect("Failed to parse PEM");
    pk.verify(rsa8::Pss::new::<rsa8::sha2::Sha256>(), hashed_data, sig)
        .expect("Failed to verify data against signature");

    println!("END RSA-8");
}

fn t_rsa9(public_key_pem: &str, hashed_data: &[u8], sig: &[u8]) {
    use rsa9::pkcs8::DecodePublicKey;
    use rsa9::RsaPublicKey;

    println!("START RSA-9");

    let pk = RsaPublicKey::from_public_key_pem(public_key_pem).expect("Failed to parse PEM");
    pk.verify(rsa9::Pss::new::<rsa9::sha2::Sha256>(), hashed_data, sig)
        .expect("Failed to verify data against signature");

    println!("END RSA-9");
}