# Unix Persist

{% hint style="success" %}
Hack Responsibly.

Always ensure you have **explicit** permission to access any computer system **before** using any of the techniques contained in these documents. You accept full responsibility for your actions by applying any knowledge gained here.
{% endhint %}

### Cron

### Startup Scripts

Add script to run at startup: `update-rc.d </path/to/the/script> defaults` (needs 755 permissions)

### Accounts

#### Add Account & Password to /etc/passwd

* Generate password with `openssl passwd -1 -salt $username $password`
* Add to `/etc/passwd` file which is in the format:
  * `$UserName:$generated_password:$UID:$GUID:$comment:$home_dir:$default_shell`
  * `$comment` is usually the user's Full Name. Check the `/etc/passwd` file to ensure you match local standards.
  * (assumes you have write privilege to this file!).