Function decrypt

tests/binary/rsa/src/main.rs:70–72

RSA decryption: m = c^d mod n

(priv_key: &PrivateKey, ciphertext: u64)

// RSA decryption: m = c^d mod n
fn decrypt(priv_key: &PrivateKey, ciphertext: u64) -> u64 {
    mod_exp(ciphertext, priv_key.d, priv_key.n)
}

// Main test function
fn main() {