Changes between Initial Version and Version 1 of TracFineGrainedPermissions


Ignore:
Timestamp:
Sep 18, 2010 11:49:36 AM (9 years ago)
Author:
trac
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • TracFineGrainedPermissions

    v1 v1  
     1= Fine grained permissions =
     2
     3Before Trac 0.11, it was only possible to define fine-grained permissions checks on the repository browser sub-system.
     4
     5Since 0.11, there's a general mechanism in place that allows custom permission policy plugins to grant or deny any action on any kind of Trac resources, even at the level of specific versions of such resources.
     6
     7Note that for Trac 0.12, `authz_policy` has been integrated in trunk branch as `tracopt.perm.authz_policy.*`
     8
     9== Permission Policies ==
     10
     11=== !AuthzPolicy ===
     12
     13An example policy based on an Authz-style system has been added. See
     14[trac:source:branches/0.11-stable/sample-plugins/permissions/authz_policy.py authz_policy.py] for details (current version requires >= Python 2.4). (See also [trac:source:branches/0.11-stable/sample-plugins/permissions sample-plugins/permissions] for more samples.)
     15
     16 - Install [http://www.voidspace.org.uk/python/configobj.html ConfigObj] (required).
     17 - Copy authz_policy.py into your plugins directory.
     18 - Put a [http://swapoff.org/files/authzpolicy.conf authzpolicy.conf] file somewhere, preferably on a secured location on the server, not readable for others than the webuser. If the  file contains non-ASCII characters, the UTF-8 encoding should be used.
     19 - Update your `trac.ini`:
     20   1. modify the [TracIni#trac-section permission_policies] entry in the `[trac]` section
     21{{{
     22[trac]
     23...
     24permission_policies = AuthzPolicy, DefaultPermissionPolicy, LegacyAttachmentPolicy
     25}}}
     26   2. add a new `[authz_policy]` section
     27{{{
     28[authz_policy]
     29authz_file = /some/trac/env/conf/authzpolicy.conf
     30}}}
     31   3. enable the single file plugin
     32{{{
     33[components]
     34...
     35authz_policy.* = enabled
     36}}}
     37
     38Note that the order in which permission policies are specified is quite critical,
     39as policies will be examined in the sequence provided.
     40
     41A policy will return either `True`, `False` or `None` for a given permission check.
     42Only if the return value is `None` will the ''next'' permission policy be consulted.
     43If no policy explicitly grants the permission, the final result will be `False`
     44(i.e. no permission).
     45
     46For example, if the `authz_file` contains:
     47{{{
     48[wiki:WikiStart@*]
     49* = WIKI_VIEW
     50
     51[wiki:PrivatePage@*]
     52john = WIKI_VIEW
     53* =
     54}}}
     55and the default permissions are set like this:
     56{{{
     57john           WIKI_VIEW
     58jack           WIKI_VIEW
     59# anonymous has no WIKI_VIEW
     60}}}
     61
     62Then:
     63 - All versions of WikiStart will be viewable by everybody (including anonymous)
     64 - !PrivatePage will be viewable only by john
     65 - other pages will be viewable only by john and jack
     66
     67
     68=== mod_authz_svn-like permission policy ===
     69
     70At the time of this writing, the old fine grained permissions system from Trac 0.10 and before used for restricting access to the repository has not yet been converted to a permission policy component, but from the user point of view, this makes little if no difference.
     71
     72That kind of fine-grained permission control needs a definition file, which is the one used by Subversion's mod_authz_svn.
     73More information about this file format and about its usage in Subversion is available in the  [http://svnbook.red-bean.com/en/1.5/svn.serverconfig.pathbasedauthz.html Path-Based Authorization] section in the Server Configuration chapter of the svn book.
     74
     75Example:
     76{{{
     77[/]
     78* = r
     79
     80[/branches/calc/bug-142]
     81harry = rw
     82sally = r
     83
     84[/branches/calc/bug-142/secret]
     85harry =
     86}}}
     87
     88 * '''/''' = ''Everyone has read access by default''
     89 * '''/branches/calc/bug-142''' = ''harry has read/write access, sally read only''
     90 * '''/branches/calc/bug-142/secret''' = ''harry has no access, sally has read access (inherited as a sub folder permission)''
     91
     92==== Trac Configuration ====
     93
     94To activate fine grained permissions you __must__ specify the {{{authz_file}}} option in the {{{[trac]}}} section of trac.ini. If this option is set to null or not specified the permissions will not be used.
     95
     96{{{
     97[trac]
     98authz_file = /path/to/svnaccessfile
     99}}}
     100
     101If you want to support the use of the `[`''modulename''`:/`''some''`/`''path''`]` syntax within the `authz_file`, add
     102
     103{{{
     104authz_module_name = modulename
     105}}}
     106
     107where ''modulename'' refers to the same repository indicated by the `repository_dir` entry in the `[trac]` section. As an example, if the `repository_dir` entry in the `[trac]` section is {{{/srv/active/svn/blahblah}}}, that would yield the following:
     108
     109{{{
     110[trac]
     111authz_file = /path/to/svnaccessfile
     112authz_module_name = blahblah
     113...
     114repository_dir = /srv/active/svn/blahblah
     115}}}
     116
     117where the svn access file, {{{/path/to/svnaccessfile}}}, contains entries such as {{{[blahblah:/some/path]}}}.
     118
     119'''Note:''' Usernames inside the Authz file __must__ be the same as those used inside trac.
     120
     121==== Subversion Configuration ====
     122
     123The same access file is typically applied to the corresponding Subversion repository using an Apache directive like this:
     124{{{
     125<Location /repos>
     126  DAV svn
     127  SVNParentPath /usr/local/svn
     128
     129  # our access control policy
     130  AuthzSVNAccessFile /path/to/svnaccessfile
     131</Location>
     132}}}
     133
     134For information about how to restrict access to entire projects in a multiple project environment see [trac:wiki:TracMultipleProjectsSVNAccess]
     135
     136== Getting TracFineGrainedPermissions to work ==
     137
     138Don't forget to restart Trac engine to apply new configuration if you are running tracd standalone server.
     139
     140----
     141See also: TracPermissions,
     142[http://trac-hacks.org/wiki/FineGrainedPageAuthzEditorPlugin TracHacks:FineGrainedPageAuthzEditorPlugin] for a simple editor plugin.