//! Implements an Aes256Siv encryption engine //! //! Can be initialised from scratch or with a pw/salt //! combintaion which derives a key via the `keybob` crate. use crate::lcc::crypto::{random, Key}; use crate::lcc::traits::{AutoEncoder, Encryptable, EncryptionHandler}; use crate::lcc::{EncryptedBody, PackedData}; use super::databody::DataBody; use miscreant::{Aead, Aes256SivAead}; impl Encryptable for DataBody {} pub struct AesEngine { ctx: Aes256SivAead, key: Key, iv: Vec<u8>, } impl AesEngine { /// Initialise an AesEngine and take ownership of a raw key pub fn new(key: Key) -> Self { assert!(key.len() == 64); Self { ctx: Aes256SivAead::new(&key.as_slice()), iv: random::bytes(64), key, } } fn encrypt_primitive(&mut self, data: &Vec<u8>) -> PackedData { let nonce = random::bytes(64); let iv = &self.iv.as_slice(); let encrypted = self.ctx.seal(nonce.as_slice(), iv, data.as_slice()); PackedData { iv: self.iv.clone(), data: encrypted, nonce: nonce, } } fn decrypt_primitive(&mut self, packed: &PackedData) -> Option<Vec<u8>> { let iv = &self.iv.as_slice(); Some( self.ctx .open(packed.nonce.as_slice(), iv, packed.data.as_slice()) .ok()?, ) } } impl EncryptionHandler<DataBody> for AesEngine { fn encrypt(&mut self, item: DataBody) -> EncryptedBody { let ser = item.encode().unwrap(); let data = self .encrypt_primitive(&ser.as_bytes().to_vec()) .encode() .unwrap(); EncryptedBody { data } } fn decrypt(&mut self, item: EncryptedBody) -> Option<DataBody> { let packed = PackedData::decode(&item.data).ok()?; Some(DataBody::decode(&String::from_utf8(self.decrypt_primitive(&packed)?).ok()?).ok()?) } }