Method decrypt_env_vars

dstack-util/src/system_setup.rs:1437–1457

(
        &self,
        key: &[u8],
        ciphertext: &[u8],
        allowed: &BTreeSet<String>,
    )

impl Stage1<'_> {
    fn decrypt_env_vars(
        &self,
        key: &[u8],
        ciphertext: &[u8],
        allowed: &BTreeSet<String>,
    ) -> Result<BTreeMap<String, String>> {
        let vars = if !key.is_empty() && !ciphertext.is_empty() {
            info!("Processing encrypted env");
            let env_crypt_key: [u8; 32] = key
                .try_into()
                .ok()
                .context("Invalid env crypt key length")?;
            let decrypted_json =
                dh_decrypt(env_crypt_key, ciphertext).context("Failed to decrypt env file")?;
            crate::parse_env_file::parse_env(&decrypted_json, allowed)?
        } else {
            info!("No encrypted env, using default");
            Default::default()
        };
        Ok(vars)
    }

    fn write_env_file(&self, env_vars: &BTreeMap<String, String>) -> Result<()> {
        info!("Writing env");