If `settings.json` contains a user without a `password` property then
nobody should be able to log in as that user using the built-in HTTP
basic authentication. This is true both with and without this change,
but before this change it wasn't immediately obvious that a malicious
user couldn't use an empty or null password to log in as such a user.
This commit adds an explicit nullish check and some unit tests to
ensure that an empty or null password will not work if the `password`
property is null or undefined.
Before this change, the authorize hook was invoked twice: once before
authentication and again after (if settings.requireAuthorization is
true). Now pre-authentication authorization is instead handled by a
new preAuthorize hook, and the authorize hook is only invoked after
the user has authenticated.
Rationale: Without this change it is too easy to write an
authorization plugin that is too permissive. Specifically:
* If the plugin does not check the path for /admin then a non-admin
user might be able to access /admin pages.
* If the plugin assumes that the user has already been authenticated
by the time the authorize function is called then unauthenticated
users might be able to gain access to restricted resources.
This change also avoids calling the plugin's authorize function twice
per access, which makes it easier for plugin authors to write an
authorization plugin that is easy to understand.
This change may break existing authorization plugins: After this
change, the authorize hook will no longer be able to authorize
non-admin access to /admin pages. This is intentional. Access to admin
pages should instead be controlled via the `is_admin` user setting,
which can be set in the config file or by an authentication plugin.
Also:
* Add tests for the authenticate and authorize hooks.
* Disable the authentication failure delay when testing.
This makes it possible for reverse proxies to transform 403 errors
into something like "upgrade to a premium account to access this
pad".
Also add some webaccess tests.