<div>
<ul>
<li><a href="#TWiki Access Control"> TWiki Access Control</a><ul>
- <li><a href="#Overview"> Overview</a></li>
+ <li><a href="#An Important Control Considerati"> An Important Control Consideration</a></li>
<li><a href="#Users and Groups"> Users and Groups</a><ul>
<li><a href="#Managing Users"> Managing Users</a></li>
<li><a href="#Managing Groups"> Managing Groups</a></li>
<li><a href="#Deny Renaming by Web"> Deny Renaming by Web</a></li>
</ul>
</li>
- <li><a href="#Restricting Read Access"> Restricting Read Access</a><ul>
- <li><a href="#Known Issues"> Known Issues</a><ul>
- <li><a href="#Selective Unrestricted Web Acces"> Selective Unrestricted Web Access</a></li>
- </ul>
- </li>
+ <li><a href="#Restricting Web Access"> Restricting Web Access</a><ul>
+ <li><a href="#Create Hidden Webs"> Create Hidden Webs</a></li>
+ <li><a href="#Create Authenticated Access By W"> Create Authenticated Access By Web</a></li>
</ul>
</li>
+ <li><a href="#Hiding Control Settings"> Hiding Control Settings</a></li>
<li><a href="#The _SuperAdminGroup"> The SuperAdminGroup</a></li>
</ul>
</li>
</ul>
</div>
-## <a name="TWiki Access Control"></a> TWiki Access Control
+# <a name="TWiki Access Control"></a> TWiki Access Control
_Restricting read and write access to topics and webs, by users and groups_
-### <a name="Overview"></a> Overview
+[[TWikiAccessControl]] allows you restrict access to single topics and entire webs, by individual user and by user groups, in three main areas: view; edit & attach; and rename/move/delete. These controls, combined with [[TWikiUserAuthentication]], let you easily create and manage an extremely flexible, fine-grained privilege system.
-%WIKITOOLNAME% allows you to define restrictions of who is allowed to view a %WIKITOOLNAME% web, make changes to topics or attach files.
+## <a name="An Important Control Considerati"></a> An Important Control Consideration
-**IMPORTANT NOTE:** Think twice before restricting read or write access to a web or a topic, because an open system where everybody can contribute is the essence of the [[WikiCulture]]. Experience shows that unrestricted write access works very well because:
+Open, freeform editing is the essence of the [[WikiCulture]] - it's what makes TWiki different and often more effective than other collaboration tools. So, it is strongly recommended that decisions to restrict read or write access to a web or a topic are made with care. Experience shows that _unrestricted write access_ works very well because:
- Peer influence is enough to ensure that only relevant content is posted.
-- Peer editing - edit anything on a page - keeps topics focussed.
+
+- Peer editing - the ability to rearrange anything on a page - keeps topics focussed.
+
- All content is preserved under revision control.
- - Edits can be undone by the [[TWikiAdminGroup]] (the default administrators group; see [[Managing Groups|Main/WebHome#ManagingGroups]]).
- - Editing and refactoring (condensing a long topic) is encouraged (there's a safety net).
+ - Edits can be undone by the [[TWikiAdminGroup]] (the default administrators group; see #ManagingGroups).
+ - Users are encouraged to edit and refactor (condense a long topic), since there's a safety net.
-### <a name="Users and Groups"></a> Users and Groups
+As a collaboration guideline:
-Access control is based on users and groups.
+- Create broad groups (more and varied input), and...
+- Avoid creating view-only users (if you can read it, you can contribute to it).
-#### <a name="Managing Users"></a> Managing Users
+## <a name="Users and Groups"></a> Users and Groups
-A user is created by with the TWikiRegistration form. The process generates a topic in the Main web in the new user's [[WikiName]]. The default visitor name is [[TWikiGuest]].
+Access control is based on users and groups. Users are defined by their [[WikiNames]], an then organized in unlimited combinations under different user groups.
-- Users can be authenticated using Basic Authentication or SSL. [[TWiki Authentication|Main/TWikiDocumentation#TWikiAuthentication]] has more.
+### <a name="Managing Users"></a> Managing Users
-<a name="ManagingGroups"></a>
+A user is created by with the [[TWikiRegistration]] form. The process generates a topic in the Main web in the new user's [[WikiName]]. The default visitor name is [[TWikiGuest]].
-#### <a name="Managing Groups"></a> Managing Groups
+- Users can be authenticated using Basic Authentication or SSL. [[TWikiUserAuthentication]] is required in order to track user identities.
-Groups are defined by group topics in the Main web, like the [[TWikiAdminGroup]].
+<a name="ManagingGroups"></a>
+
+### <a name="Managing Groups"></a> Managing Groups
-- A group topic name must end in **\_Group**
-- The group topic should define these two variables:
+Groups are defined by group topics in the <code>**Main**</code> web, like the [[TWikiAdminGroup]]. To start a new group:
-> - - Set GROUP = < list of users and groups >
-> - Set ALLOWTOPICCHANGE = < list of users and groups >
+1. **Create** a new topic with A name that ends in **Group**, `SomeGroup`
+2. **Define** two variables:
+ - Set GROUP = < list of users and groups >
+ - Set ALLOWTOPICCHANGE = < list of users and groups >
-- GROUP defines the members of the group; it is a comma delimited list of users and other groups. Example: <br /><code>** \* Set GROUP = Main.SomeUser, Main.OtherUser, Main.SomeOtherGroup**</code>
-- ALLOWTOPICCHANGE defines who is allowed to change the group topic; it is a comma delimited list of users and groups. You typically want to restrict that to the members of the group itself, so it should contain the name of the topic, i.e. <br />` * Set ALLOWTOPICCHANGE = Main.TWikiAdminGroup`<br /> for the TWikiAdminGroup topic. (This is to prevent users not in the group from editing the topic and gaining unauthorized membership to the group.)
+- GROUP is a comma-separated list of users and of other groups:<br /><code>** Set GROUP = Main.SomeUser, Main.OtherUser, Main.SomeOtherGroup**</code>
-### <a name="Restricting Write Access"></a> Restricting Write Access
+- ALLOWTOPICCHANGE defines who is allowed to change the group topic; it is a comma delimited list of users and groups. You typically want to restrict that to the members of the group itself, so it should contain the name of the topic,<br /><code>** Set ALLOWTOPICCHANGE = Main.TWikiAdminGroup**</code><br /> for the TWikiAdminGroup topic. (This prevents users not in the group from editing the topic and from gaining unauthorized membership to the group.)
-#### <a name="Deny Editing by Topic"></a> Deny Editing by Topic
+## <a name="Restricting Write Access"></a> Restricting Write Access
-You can define restrictions of who is allowed to make changes to a topic or attach files to it.
+You can define who is allowed to make changes to a web or a topic.
-Define one or both of these variables in a topic, preferably at the end of the topic:
+### <a name="Deny Editing by Topic"></a> Deny Editing by Topic
-- Set DENYTOPICCHANGE = < list of users and groups >
-- Set ALLOWTOPICCHANGE = < list of users and groups >
+Denying editing of a topic also restricts attaching files to it; both privileges are assigned together.
-DENYTOPICCHANGE defines users or groups that **are not** allowed to make changes to the topic. It is a comma delimited list of users and groups. Example: <br />` * Set DENYTOPICCHANGE = Main.SomeBadBoy, Main.SomeBadGirl, Main.SomeHackerGroup`
+- Define one or both of these variables in a topic, preferably at the end of the page:
+ - Set DENYTOPICCHANGE = < list of users and groups >
+ - Set ALLOWTOPICCHANGE = < list of users and groups >
-ALLOWTOPICCHANGE defines users or groups that **are** allowed to make changes to the topic. It is a comma delimited list of users and groups. Example: <br />` * Set ALLOWTOPICCHANGE = Main.SomeGoodGuy, Main.SomeGoodGirl, Main.TWikiAdminGroup`
+- DENYTOPICCHANGE defines users or groups that **are not** allowed to make changes to the topic. It is a comma delimited list of users and groups. Example: <br />` * Set DENYTOPICCHANGE = Main.SomeBadBoy, Main.SomeBadGirl, Main.SomeHackerGroup`
-DENYTOPICCHANGE is evaluated before ALLOWTOPICCHANGE. Access is denied if the authenticated person is in the DENYTOPICCHANGE list, or not in the ALLOWTOPICCHANGE list. Access is granted in case DENYTOPICCHANGE and ALLOWTOPICCHANGE is not defined.
+- ALLOWTOPICCHANGE defines users or groups that **are** allowed to make changes to the topic. It is a comma delimited list of users and groups. Example: <br />` * Set ALLOWTOPICCHANGE = Main.SomeGoodGuy, Main.SomeGoodGirl, Main.TWikiAdminGroup`
-#### <a name="Deny Editing by Web"></a> Deny Editing by Web
+- DENYTOPICCHANGE is evaluated before ALLOWTOPICCHANGE. Access is denied if the authenticated person is in the DENYTOPICCHANGE list, or not in the ALLOWTOPICCHANGE list. Access is granted in case DENYTOPICCHANGE and ALLOWTOPICCHANGE is not defined.
-You can define restrictions of who is allowed to make changes to a %WIKITOOLNAME% web. This includes creating new topics, changing topics or attaching files.
+### <a name="Deny Editing by Web"></a> Deny Editing by Web
-Define one or both of these variable in the [[WebPreferences]] topic:
+Restricting web-level editing blocks creating new topics, changing topics or attaching files.
-- Set DENYWEBCHANGE = < list of users and groups >
-- Set ALLOWWEBCHANGE = < list of users and groups >
+- Define one or both of these variable in the [[WebPreferences]] topic:
+ - Set DENYWEBCHANGE = < list of users and groups >
+ - Set ALLOWWEBCHANGE = < list of users and groups >
-The same rules apply like the one for Access Control for Individual Topics; with these additions:
+The same rules apply as for restricting topics, with these additions:
- DENYTOPICCHANGE (in topic) overrides DENYWEBCHANGE (in WebPreferences)
- ALLOWTOPICCHANGE (in topic) overrides ALLOWWEBCHANGE (in WebPreferences)
-### <a name="Restricting Rename Access"></a> Restricting Rename Access
-
-#### <a name="Deny Renaming by Topic"></a> Deny Renaming by Topic
+## <a name="Restricting Rename Access"></a> Restricting Rename Access
-You can define restrictions of who is allowed to rename a topic. Note that users need this permission in addition to the CHANGE permission in order to rename a topic. They also need CHANGE access to change references in referring topics.
+You can define who is allowed to rename, move or delete a topic, or rename a web.
-Define one or both of these variables in a topic, preferably at the end of the topic:
+### <a name="Deny Renaming by Topic"></a> Deny Renaming by Topic
-- Set DENYTOPICRENAME = < list of users and groups >
-- Set ALLOWTOPICRENAME = < list of users and groups >
+To allow a user to rename, move or delete a topic, they also need write (editing) permission. They also need write access to change references in referring topics.
-DENYTOPICCRENAME defines users or groups that **are not** allowed to rename the topic. It is a comma delimited list of users and groups. Example: <br />` * Set DENYTOPICRENAME = Main.SomeBadBoy, Main.SomeBadGirl, Main.SomeHackerGroup`
+- Define one or both of these variables in a topic, preferably at the end of the topic:
+ - Set DENYTOPICRENAME = < list of users and groups >
+ - Set ALLOWTOPICRENAME = < list of users and groups >
-ALLOWTOPICRENAME defines users or groups that **are** allowed to rename the topic. It is a comma delimited list of users and groups. Example: <br />` * Set ALLOWTOPICRENAME = Main.SomeGoodGuy, Main.SomeGoodGirl, Main.TWikiAdminGroup`
+- DENYTOPICCRENAME defines users or groups that **are not** allowed to rename the topic. It is a comma delimited list of users and groups. Example: <br />` * Set DENYTOPICRENAME = Main.SomeBadBoy, Main.SomeBadGirl, Main.SomeHackerGroup`
-DENYTOPICRENAME is evaluated before ALLOWTOPICRENAME. Access is denied if the authenticated person is in the DENYTOPICRENAME list, or not in the ALLOWTOPICRENAME list. Access is granted in case DENYTOPICRENAME and ALLOWTOPICRENAME is not defined.
+- ALLOWTOPICRENAME defines users or groups that **are** allowed to rename the topic. It is a comma delimited list of users and groups. Example: <br />` * Set ALLOWTOPICRENAME = Main.SomeGoodGuy, Main.SomeGoodGirl, Main.TWikiAdminGroup`
-#### <a name="Deny Renaming by Web"></a> Deny Renaming by Web
+- DENYTOPICRENAME is evaluated before ALLOWTOPICRENAME. Access is denied if the authenticated person is in the DENYTOPICRENAME list, or not in the ALLOWTOPICRENAME list. Access is granted in case DENYTOPICRENAME and ALLOWTOPICRENAME is not defined.
-You can define restrictions of who is allowed to do renames for a %WIKITOOLNAME% web.
+### <a name="Deny Renaming by Web"></a> Deny Renaming by Web
-Define one or both of these variable in the [[WebPreferences]] topic:
+You can define restrictions of who is allowed to rename a %WIKITOOLNAME% web.
-- Set DENYWEBRENAME = < list of users and groups >
-- Set ALLOWWEBRENAME = < list of users and groups >
+- Define one or both of these variable in the [[WebPreferences]] topic:
+ - Set DENYWEBRENAME = < list of users and groups >
+ - Set ALLOWWEBRENAME = < list of users and groups >
-The same rules apply like the one for Access Control for Individual Topics; with these additions:
+The same rules apply as for topics, with these additions:
- DENYTOPICRENAME (in topic) overrides DENYWEBRENAME (in WebPreferences)
- ALLOWTOPICRENAME (in topic) overrides ALLOWWEBRENAME (in WebPreferences)
-### <a name="Restricting Read Access"></a> Restricting Read Access
+## <a name="Restricting Web Access"></a> Restricting Web Access
-You can define restrictions of who is allowed to view a %WIKITOOLNAME% web.
+You can prevent selected users and groups from accessing certain webs, by hiding them using restricting read access, or by requiring login. There are two basic methods, one simple, using standard preferences variables to hide a web, but offering low security, and a secure log-in approach that is currently a workaround, involving some minor script and filesystem modification.
-Define one or both of these variable in the [[WebPreferences]] topic:
+### <a name="Create Hidden Webs"></a> Create Hidden Webs
-- Set DENYWEBVIEW = < list of users and groups >
-- Set ALLOWWEBVIEW = < list of users and groups >
+You can prevent selected users and groups from viewing certain %WIKITOOLNAME% webs by setting one or both of these variables in each web's [[WebPreferences]] topic:
-#### <a name="Known Issues"></a> Known Issues
+- - Set DENYWEBVIEW = < list of users and groups >
+ - Set ALLOWWEBVIEW = < list of users and groups >
+- If keeping a hidden web out of general use is a consideration, you should also prevent the "all webs" search option from accessing each hidden web, by enabling the <code>**NOSEARCHALL**</code> variable in [[WebPreferences]]:
+ - Set NOSEARCHALL = on
+ - It is not recommended to restrict view access to individual topics since all content is searchable _within_ a web.
+- %H%This method only works if the <code>**view**</code> script is authenticated, which means that all users have to login, even for read-only access. (An open guest account, like [[TWikiGuest]], can get around this, allowing anyone to login with, for example, view-only access for public webs.) [[TWikiInstallationGuide]] has more on Basic Authentication, using the <code>**.htaccess**</code> file.
+- %X% **Hiding webs is not very secure**, as there is a way to circumvent the read access restriction. It can be useful in certain situations - for example, to simplify site organization and clutter, by hiding low traffic webs - but is not recommended for securing sensitive content.
+
+### <a name="Create Authenticated Access By W"></a> Create Authenticated Access By Web
+
+To selectively restrict web access with the security of Basic Authentication, there is a reliable workaround that involves some straightforward code modification:
+
+1. Set aside the <code>**view**</code> script (rename) and create a <code>**view**</code> subdirectory in its place.
+2. In the <code>**view**</code> subdirectory, create a separate copy of a modified viewing script for each web, and create <code>**.htaccess**</code> settings for the restricted webs.
+ - %T% You can use symbolic links to a single copy of the viewing script to make any script updates that much easier.
+
+> **Example of viewing script**
+>
+> <code>**redirect**</code>
+>
+> #!/usr/bin/perl -w
+> #
+>
+> chdir '..';
+>
+> # Adjust SCRIPT and PATH_INFO variables to account for the changed directory
+> my $web = $ENV{SCRIPT_NAME};
+> $web =~ s#^.*/view(/[^/]*).*$#$1#; # isolate the path element after "view"
+> $ENV{PATH_TRANSLATED} =~ s#(/[^/]*)$#$web$1#;
+> $ENV{PATH_INFO} =~ s#(/[^/]*)$#$web$1#;
+> $ENV{SCRIPT_NAME} =~ s#/view$web#/view#;
+> $ENV{SCRIPT_FILENAME} =~ s#/view$web#/view#;
+>
+> # open (LOG, '>>/tmp/redirect.log');
+> # print LOG join ("\n", scalar localtime (time ()), %ENV);
+> # close LOG;
+> exec ('/usr/bin/perl', '-wT', 'view.orig') or
+>
+> print <<EOF;
+> Content-type: text/plain
+>
+> Error executing /cgi-bin/view.orig: $?
+> Click the BACK button in your browser and contact webmaster\@bcs-oops.org.
+>
+> EOF
+
+- **_(Mod by [[ImmoHuneke]] - 16 Mar 2002)_**
+
+**A SECOND OPTION:** A less reliable workaround that also requires code changes is available to provide the same unrestricted viewing access, with authentication required only on selected webs:
+
+1. **Omit** the <code>**view**</code> script from the `.htaccess` file.
+2. **Enable** the <code>**$doRememberRemoteUser**</code> flag in <code>**lib/TWiki.cfg**</code> as described in [[TWikiUserAuthentication]]. %WIKITOOLNAME% will now remember the IP address of an authenticated user. 1. **Copy** the <code>**view**</code> script to <code>**viewauth**</code> (or better, create a symbolic link) 1. **Add** <code>**viewauth**</code> to the list of authenticated scripts in the .htaccess file.
+ - When a user accesses a web where you enabled view restriction, %WIKITOOLNAME% will redirect from the `view` script to the `viewauth` script once (this happens only if the user has never edited a topic). Doing so will ask for authentication. The `viewauth` script shows the requested topic if the user could log on and if the user is authorized to see that web.
+ - If you enable view restriction for a web, it is recommended to restrict search "all webs" from searching this web. Enable this restriction with the <code>**NOSEARCHALL**</code> variable in its [[WebPreferences]], like:
+ - Set NOSEARCHALL = on
+ - It is not recommended to restrict view access to individual topics since all content is searchable _within_ a web.
-- The view restriction is not suitable for very sensitive content since there is a way to circumvent the read access restriction.
-- Read access restriction only works if the view script is authenticated, that means that users need to log on also just to read topics. [[TWiki Installation Guide|Main/TWikiDocumentation#TWikiInstallationGuide]] has more on Basic Authentication based on the <code>**.htaccess**</code> file.
+## <a name="Hiding Control Settings"></a> Hiding Control Settings
-##### <a name="Selective Unrestricted Web Acces"></a> Selective Unrestricted Web Access
+- %T% To hide access control settings from normal browser viewing, place them in comment markers.
-- There is a workaround if you prefer to have unrestricted access to view topics located in normal webs, and to authenticate users only for webs where view restriction is enabled:
- - Leave the <code>**view**</code> script non-authenticated in the `.htaccess` file.
- - Enable the <code>**$doRememberRemoteUser**</code> flag in <code>**lib/wikicfg.pm**</code> as described in [[User Authentication|Main/TWikiDocumentation#TWikiUserAuthentication]]. %WIKITOOLNAME% will now remember the IP address of an authenticated user.
- - Copy the <code>**view**</code> script to <code>**viewauth**</code> (or better, create a symbolic link)
- - Add <code>**viewauth**</code> to the list of authenticated scripts in the .htaccess file.
- - When a user accesses a web where you enabled view restriction, %WIKITOOLNAME% will redirect from the `view` script to the `viewauth` script once (this happens only if the user has never edited a topic). Doing so will ask for authentication. The `viewauth` script shows the requested topic if the user could log on and if the user is authorized to see that web.
-- If you enable view restriction for a web, it is recommended to restrict search "all webs" from searching this web. Enable this restriction with the <code>**NOSEARCHALL**</code> variable in its [[WebPreferences]], like:
- - Set NOSEARCHALL = on
-- It is not recommended to restrict view access to individual topics since all content is searchable _within_ a web.
+> <!--
+>
+> <br />
+>
+> Set DENYTOPICCHANGE = Main.SomeGroup
+>
+> <br />
+>
+> -->
-### <a name="The _SuperAdminGroup"></a> The SuperAdminGroup
+<a name="SuperAdminGroup"></a>
-The above schema can lock completely a topic in case of a typing error of the ALLOWTOPICCHANGE setting (see [[UnchangeableTopicBug]] for more detail). To avoid this:
+## <a name="The _SuperAdminGroup"></a> The SuperAdminGroup
-- Set the <code>**$superAdminGroup**</code> variable in <code>**lib/TWiki.cfg**</code> to the name of a group of users that are always allowed to edit/view topics.
+By mistyping a user or group name in the ALLOWTOPICCHANGE setting, it's possible to lock a topic so that it no-one can edit it from a browser. To avoid this:
- $superAdminGroup = "TWikiAdminGroup";
+- Set the `$superAdminGroup` variable in `lib/TWiki.cfg` to the name of a group of users that are always allowed to edit/view topics.
-- The default setting is not to have superusers.
+> $superAdminGroup = "TWikiAdminGroup";
--- [[PeterThoeny]] - 16 Mar 2001 <br /> -- [[AndreaSterbini]] - 11 Apr 2001 <br />
+- The default setting is not to have superusers.
-**_Related topics:_** [[TWikiPreferences]], [[WebPreferences]] (in every web), [[TWikiAdminGroup]], [[TWikiGroups]]
+-- [[MikeMannix]] - 20 Mar 2002
git://git.openafs.org / openafs-wiki.git / blobdiff