Diff: Help/PagePermissions

Differences between current version and predecessor to the previous major change of Help/PagePermissions.

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current version

Full recursive ACL page permissions support (Solaris / Windows style)

Boolean permissions per page and action (granted or denied) based on the current users group membership is implemented with ACL's (Access Control Lists). Opposed to the simplier unix like ugo:rwx system.
The previous system was only based on action and current user, independent of pages.

A individual page permission may be inherited from its parent pages, and from an optional master page ("." or _dotpage').
Use predefined default permissions, if a "." page does not exist.
Pagenames starting with "." have tighter default permissions. (edit, change, list disallowed)

Order of Evaluation (denial overrides granted, or vice versa?)

The array of permissions is evaluated from top to bottom.
Access is granted if the next matching group membership returns true, denied if false.
If the group membership is false, the next group is tried.
If no group membership matches the upper permissions are tried recursively:

current page => basepage => "." page => default perms.

If no group-perm pair grants access, access is denied.

Consider the following perm:

     'change' => array(ACL_ADMIN => false,
                       ACL_OWNER => true));

=> "Members of ADMIN may not change, the owner may change."

For Authentication see WikiUser.php, WikiGroup.php and main.php

I suspect ACL page permissions to degrade performance by 10%

Enable/Disable it in config/config.ini

ENABLE_PAGEPERM = true

The defined (and extendable) main.php actions map to simplier access types:

       browse => view
       edit   => edit
       create => edit or create
       remove => remove
       rename => change
       store prefs => change
       list in PageList => list

For simplicity we also map the ACL to the posix-style owner, group and world groups and read, write, execute perms, in cygwin fashion.

Groups - definition of group membership

See WikiGroup how to enable and where to store user-specific group membership. Group methods: database, file, ldap, wikipage, none

To do: explain better.

The following special groups are always predefined, even if no other group methods are provided:

• _EVERY
• _ANONYMOUS
• _BOGOUSER
• _HASHOMEPAGE
• _SIGNED
• _AUTHENTICATED
• _ADMIN
• _OWNER
• _CREATOR

Those special groups are stored in a page acl as locale-independent string.

To do: See the available translations for these special groups.

Other group names are safed as defined by the group methods. (e.g. "Other Users")

Perms - mapping of actions to permissions

PhpWiki supports individual actions, the default is browse. To simplify ACL's these actions are mapped to some special permissions (vulgo 'perms').

We currently support the following permissions which can be stored in every page, for every group.

There are no plans to support additional custom perms. The API can handle that, but there's no UI, and it would be only specific for certain plugins, which check permissions by their own.

Action <=> Perm mapping

Those perms are mapped to those actions. Action Pages (plugins) check their access restrictions by themselves.

Default Permissions

        $perm = array('view'   => array(ACL_EVERY => true),
                      'edit'   => array(ACL_EVERY => true),
                      'create' => array(ACL_EVERY => true),
                      'list'   => array(ACL_EVERY => true),
                      'remove' => array(ACL_ADMIN => true,
                                        ACL_OWNER => true),
                      'change' => array(ACL_ADMIN => true,
                                        ACL_OWNER => true));
        if (ZIPDUMP_AUTH)
            $perm['dump'] = array(ACL_ADMIN => true,
                                  ACL_OWNER => true);
        else
            $perm['dump'] = array(ACL_EVERY => true);
        // view:
        if (!ALLOW_ANON_USER) {
            if (!ALLOW_USER_PASSWORDS)
                $perm['view'] = array(ACL_SIGNED => true);
            else
                $perm['view'] = array(ACL_AUTHENTICATED => true);
            $perm['view'][ACL_BOGOUSER] = ALLOW_BOGO_LOGIN ? true : false;
        }
        // edit:
        if (!ALLOW_ANON_EDIT) {
            if (!ALLOW_USER_PASSWORDS)
                $perm['edit'] = array(ACL_SIGNED => true);
            else
                $perm['edit'] = array(ACL_AUTHENTICATED => true);
            $perm['edit'][ACL_BOGOUSER] = ALLOW_BOGO_LOGIN ? true : false;
            $perm['create'] = $perm['edit'];
        }
        return $perm;