src/crypto.rs

   1 use openssl::{symm, sha::sha256};
   2 use rand::prelude::*;
   3
   4 /// Encrypt the given text with the given key. The key length must be 128 bits encoded in base64.
   5 /// Ouput format:
   6 /// Format "1" + base_64(<IV> + <hash(message)> + <aes(message)>)
   7 /// IV: 16 bytes randomized.
   8 /// Mode : CBC.
   9 pub fn encrypt(key: &str, plain_text: &str) -> String {
  10     let key_as_bytes = base64::decode(key).expect("Unable to decode base64 encoded key");
  11     assert!(key_as_bytes.len() == 16);
  12
  13     let text_as_bytes = plain_text.as_bytes();
  14
  15     let iv = rand::thread_rng().gen::<[u8; 16]>();
  16
  17     let cipher_text =
  18         symm::encrypt(symm::Cipher::aes_128_cbc(), &key_as_bytes, Some(&iv), text_as_bytes)
  19             .expect("Unable to encrypt message");
  20
  21     let hash_text = sha256(&text_as_bytes);
  22
  23     let mut result: Vec<u8> = Vec::new();
  24     result.extend(&iv);
  25     result.extend(&hash_text);
  26     result.extend(&cipher_text);
  27
  28     String::from("1") + &base64::encode(&result)
  29 }
  30
  31 pub fn decrypt(key: &str, cipher_text: &str) -> Option<String> {
  32     if cipher_text.chars() != '1' {
  33         return None;
  34     }
  35
  36     println!("cypher: {}", cipher_text);
  37     Some(String::new())
  38 }