Small WordPress plugin to auto-login users from a link

SPAM BIDS WARNING: Your bid will be rejected automatically if it appears to be generated by a bot: * it asks for more information without asking a *specific question*; or * it asks me to contact you to discuss the project without saying what information is required. Thank you for your understanding. --- I would like someone to create an open source and released/documented [login to view URL] plugin to automatically log in users from a link. The link would look like [login to view URL] and assuming the 'user' and 'secret' parameters are okay, the user should be redirected to the value of the 'url' parameter. Otherwise it should redirect to a different page configured in the plugin's settings (see below). This is functionality I need as part of a much wider project, and I felt it was something I wanted to contribute back to the extraordinary WordPress community. The overall technique to use to auto login is documented on Stack Overflow: [login to view URL] However, that's not a plugin, doesn't use a 'salt', and uses old MD5 hash instead of my desired SHA256 hash. Also I think this technique will be useful to intercept the link in the plugin init code: [login to view URL] The plugin also needs a settings page with these settings an admin can configure: 1. page address to intercept, by default: /auto-login 2. shared 'salt' which is concatenated with the users's email and then hashed using SHA256 (by default a random 30 character string created when the plugin is first initialised) 3. multiselect/checkboxes to select which WordPress User Role(s) can be automatically logged in (e.g. probably don't want Admins logged in automatically) 4. the default page to redirect to if the link param 'url' is NOT provided (by default /my-account/) 5. the page to redirect to if the secret hash and email are incorrect (by default /[login to view URL]). The plugin needs to be released on GitHub with a GPL licence, and on [login to view URL] with sufficient documentation for someone to understand what it does and how to use it, including a screenshot of the settings screen. Note there is another plugin [login to view URL] but this doesn't have the functionality I'm looking for.