Changes between Version 1 and Version 2 of TracFineGrainedPermissions


Ignore:
Timestamp:
Dec 31, 2012, 5:48:45 PM (7 years ago)
Author:
trac
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • TracFineGrainedPermissions

    v1 v2  
    33Before Trac 0.11, it was only possible to define fine-grained permissions checks on the repository browser sub-system.
    44
    5 Since 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.
     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 as an optional module (in `tracopt.perm.authz_policy.*`), so it's installed by default and can simply be activated via the //Plugins// panel in the Trac administration module.
     8
    69
    710== Permission Policies ==
    811
    9 === !AuthzPolicy ===
    10 
    11 An example policy based on an Authz-style system has been added. See
    12 [source:trunk/sample-plugins/permissions/authz_policy.py] for details. (See also [source:trunk/sample-plugins/permissions] for more samples.)
    13 
    14  - Install [http://www.voidspace.org.uk/python/configobj.html ConfigObj] (required).
    15  - Copy authz_policy.py into your plugins directory.
    16  - 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.
    17  - Update your `trac.ini`:
     12A great diversity of permission policies can be implemented, and Trac comes with a few examples.
     13
     14Which policies are currently active is determined by a configuration setting in TracIni:
     15e.g.
     16{{{
     17[trac]
     18permission_policies = AuthzSourcePolicy, DefaultPermissionPolicy, LegacyAttachmentPolicy
     19}}}
     20This lists the [#AuthzSourcePolicy] described below as the first policy, followed by the !DefaultPermissionPolicy which checks for the traditional coarse grained style permissions described in TracPermissions, and the !LegacyAttachmentPolicy which knows how to use the coarse grained permissions for checking the permissions available on attachments.
     21
     22Among the possible optional choices, there is [#AuthzPolicy], a very generic permission policy, based on an Authz-style system. See
     23[trac:source:branches/0.12-stable/tracopt/perm/authz_policy.py authz_policy.py] for details.
     24
     25Another popular permission policy [#AuthzSourcePolicy], re-implements the pre-0.12 support for checking fine-grained permissions limited to Subversion repositories in terms of the new system.
     26
     27See also [trac:source:branches/0.12-stable/sample-plugins/permissions sample-plugins/permissions] for more examples.
     28
     29
     30=== !AuthzPolicy ===
     31==== Configuration ====
     32* Install [http://www.voidspace.org.uk/python/configobj.html ConfigObj] (still needed for 0.12).
     33* Copy authz_policy.py into your plugins directory.
     34* 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.
     35* Update your `trac.ini`:
     36  1. modify the [TracIni#trac-section permission_policies] entry in the `[trac]` section
    1837{{{
    1938[trac]
    2039...
    2140permission_policies = AuthzPolicy, DefaultPermissionPolicy, LegacyAttachmentPolicy
    22 
     41}}}
     42  2. add a new `[authz_policy]` section
     43{{{
    2344[authz_policy]
    2445authz_file = /some/trac/env/conf/authzpolicy.conf
    25 
     46}}}
     47  3. enable the single file plugin
     48{{{
    2649[components]
    2750...
    28 authz_policy = enabled
    29 }}}
    30 
     51# Trac 0.12
     52tracopt.perm.authz_policy.* = enabled
     53# for Trac 0.11 use this
     54#authz_policy.* = enabled
     55}}}
     56==== Usage Notes ====
    3157Note that the order in which permission policies are specified is quite critical,
    3258as policies will be examined in the sequence provided.
    3359
    34 A policy will return either `True`, `False` or `None` for a given permission check.
    35 Only if the return value is `None` will the ''next'' permission policy be consulted.
    36 If no policy explicitly grants the permission, the final result will be `False`
    37 (i.e. no permission).
     60A policy will return either `True`, `False` or `None` for a given permission check. `True` is returned if the policy explicitly grants the permission. `False` is returned if the policy explicitly denies the permission. `None` is returned if the policy is unable to either grant or deny the permission.
     61
     62NOTE: Only if the return value is `None` will the ''next'' permission policy be consulted.
     63If none of the policies explicitly grants the permission, the final result will be `False`
     64(i.e. permission denied).
     65
     66The `authzpolicy.conf` file is a `.ini` style configuration file:
     67{{{
     68[wiki:PrivatePage@*]
     69john = WIKI_VIEW, !WIKI_MODIFY
     70jack = WIKI_VIEW
     71* =
     72}}}
     73* Each section of the config is a glob pattern used to match against a Trac resource
     74  descriptor. These descriptors are in the form:
     75{{{
     76<realm>:<id>@<version>[/<realm>:<id>@<version> ...]
     77}}}
     78  Resources are ordered left to right, from parent to child. If any
     79  component is inapplicable, `*` is substituted. If the version pattern is
     80  not specified explicitely, all versions (`@*`) is added implicitly
     81
     82  Example: Match the WikiStart page
     83{{{
     84[wiki:*]
     85[wiki:WikiStart*]
     86[wiki:WikiStart@*]
     87[wiki:WikiStart]
     88}}}
     89
     90  Example: Match the attachment `wiki:WikiStart@117/attachment/FOO.JPG@*`
     91  on WikiStart
     92{{{
     93[wiki:*]
     94[wiki:WikiStart*]
     95[wiki:WikiStart@*]
     96[wiki:WikiStart@*/attachment/*]
     97[wiki:WikiStart@117/attachment/FOO.JPG]
     98}}}
     99
     100* Sections are checked against the current Trac resource descriptor '''IN ORDER''' of
     101  appearance in the configuration file. '''ORDER IS CRITICAL'''.
     102
     103* Once a section matches, the current username is matched against the keys
     104  (usernames) of the section, '''IN ORDER'''.
     105  * If a key (username) is prefixed with a `@`, it is treated as a group.
     106  * If a value (permission) is prefixed with a `!`, the permission is
     107    denied rather than granted.
     108
     109  The username will match any of 'anonymous',
     110  'authenticated', <username> or '*', using normal Trac permission rules.
    38111
    39112For example, if the `authz_file` contains:
     
    44117[wiki:PrivatePage@*]
    45118john = WIKI_VIEW
    46 * =
     119* = !WIKI_VIEW
    47120}}}
    48121and the default permissions are set like this:
     
    54127
    55128Then:
    56  - All versions of WikiStart will be viewable by everybody (including anonymous)
    57  - !PrivatePage will be viewable only by john
    58  - other pages will be viewable only by john and jack
    59 
    60 
    61 === mod_authz_svn-like permission policy ===
    62 
    63 At 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 differences.
     129  * All versions of WikiStart will be viewable by everybody (including anonymous)
     130  * !PrivatePage will be viewable only by john
     131  * other pages will be viewable only by john and jack
     132
     133Groups:
     134{{{
     135[groups]
     136admins = john, jack
     137devs = alice, bob
     138
     139[wiki:Dev@*]
     140@admins = TRAC_ADMIN
     141@devs = WIKI_VIEW
     142* =
     143
     144[*]
     145@admins = TRAC_ADMIN
     146* =
     147}}}
     148
     149Then:
     150- everything is blocked (whitelist approach), but
     151- admins get all TRAC_ADMIN everywhere and
     152- devs can view wiki pages.
     153
     154Some repository examples (Browse Source specific):
     155{{{
     156# A single repository:
     157[repository:test_repo@*]
     158john = BROWSER_VIEW, FILE_VIEW
     159# John has BROWSER_VIEW and FILE_VIEW for the entire test_repo
     160
     161# All repositories:
     162[repository:*@*]
     163jack = BROWSER_VIEW, FILE_VIEW
     164# John has BROWSER_VIEW and FILE_VIEW for all repositories
     165}}}
     166
     167Very fine grain repository access:
     168{{{
     169# John has BROWSER_VIEW and FILE_VIEW access to trunk/src/some/location/ only
     170[repository:test_repo@*/source:trunk/src/some/location/*@*]
     171john = BROWSER_VIEW, FILE_VIEW
     172
     173
     174# John has BROWSER_VIEW and FILE_VIEW access to only revision 1 of all files at trunk/src/some/location only
     175[repository:test_repo@*/source:trunk/src/some/location/*@1]
     176john = BROWSER_VIEW, FILE_VIEW
     177
     178
     179# John has BROWSER_VIEW and FILE_VIEW access to all revisions of 'somefile' at trunk/src/some/location only
     180[repository:test_repo@*/source:trunk/src/some/location/somefile@*]
     181john = BROWSER_VIEW, FILE_VIEW
     182
     183
     184# John has BROWSER_VIEW and FILE_VIEW access to only revision 1 of 'somefile' at trunk/src/some/location only
     185[repository:test_repo@*/source:trunk/src/some/location/somefile@1]
     186john = BROWSER_VIEW, FILE_VIEW
     187}}}
     188
     189Note: In order for Timeline to work/visible for John, we must add CHANGESET_VIEW to the above permission list.
     190
     191
     192=== !AuthzSourcePolicy  (mod_authz_svn-like permission policy) === #AuthzSourcePolicy
     193
     194At the time of this writing, the old fine grained permissions system from Trac 0.11 and before used for restricting access to the repository has  been converted to a permission policy component, but from the user point of view, this makes little if no difference.
    64195
    65196That kind of fine-grained permission control needs a definition file, which is the one used by Subversion's mod_authz_svn.
    66 More information about this file format and about its usage in Subversion is available in the [http://svnbook.red-bean.com/svnbook/book.html#svn-ch-6-sect-4.4.2 Subversion Book (Per-Directory Access Control)].
     197More 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.
    67198
    68199Example:
     
    92223}}}
    93224
    94 if you want to support the use of the `[`''modulename''`:/`''some''`/`''path''`]` syntax within the `authz_file`, add
     225If you want to support the use of the `[`''modulename''`:/`''some''`/`''path''`]` syntax within the `authz_file`, add
    95226
    96227{{{
     
    98229}}}
    99230
    100 where ''modulename'' refers to the same repository indicated by the `repository_dir` entry in the `[trac]` section.
     231where ''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:
     232
     233{{{
     234[trac]
     235authz_file = /path/to/svnaccessfile
     236authz_module_name = blahblah
     237...
     238repository_dir = /srv/active/svn/blahblah
     239}}}
     240
     241where the svn access file, {{{/path/to/svnaccessfile}}}, contains entries such as {{{[blahblah:/some/path]}}}.
    101242
    102243'''Note:''' Usernames inside the Authz file __must__ be the same as those used inside trac.
     244
     245As of version 0.12, make sure you have ''!AuthzSourcePolicy'' included in the permission_policies list in trac.ini, otherwise the authz permissions file will be ignored.
     246
     247{{{
     248[trac]
     249permission_policies = AuthzSourcePolicy, DefaultPermissionPolicy, LegacyAttachmentPolicy
     250}}}
    103251
    104252==== Subversion Configuration ====
     
    117265For information about how to restrict access to entire projects in a multiple project environment see [trac:wiki:TracMultipleProjectsSVNAccess]
    118266
     267== Debugging permissions
     268In trac.ini set:
     269{{{
     270[logging]
     271log_file = trac.log
     272log_level = DEBUG
     273log_type = file
     274}}}
     275
     276And watch:
     277{{{
     278tail -n 0 -f log/trac.log | egrep '\[perm\]|\[authz_policy\]'
     279}}}
     280
     281to understand what checks are being performed. See the sourced documentation of the plugin for more info.
     282
     283
    119284----
    120 See also: TracPermissions
     285See also: TracPermissions,
     286[http://trac-hacks.org/wiki/FineGrainedPageAuthzEditorPlugin TracHacks:FineGrainedPageAuthzEditorPlugin] for a simple editor plugin.