Catalyst::Plugin::Authorization::ACL(3pm)

1Catalyst::Plugin::AuthoUrsiezratCioonnt:r:iAbCuLt(e3d)PCeartlalDyosctu:m:ePnltuagtiino:n:Authorization::ACL(3)
2
3
4

NAME

6       Catalyst::Plugin::Authorization::ACL - ACL support for Catalyst
7       applications.
8

SYNOPSIS

10               use Catalyst qw/
11                       Authentication
12                       Authorization::Roles
13                       Authorization::ACL
14               /;
15
16               __PACKAGE__->setup;
17
18               __PACKAGE__->deny_access_unless(
19                       "/foo/bar",
20                       [qw/nice_role/],
21               );
22
23               __PACKAGE__->allow_access_if(
24                       "/foo/bar/gorch",
25                       sub { return $boolean },
26               );
27

DESCRIPTION

29       This module provides Access Control List style path protection, with
30       arbitrary rules for Catalyst applications. It operates only on the
31       Catalyst private namespace, at least at the moment.
32
33       The two hierarchies of actions and controllers in Catalyst are:
34
35       Private Namespace
36           Every action has its own private path. This path reflects the Perl
37           namespaces the actions were born in, and the namespaces of their
38           controllers.
39
40       External Namespace
41           Some actions are also directly accessible from the outside, via a
42           URL.
43
44           The private and external paths will be the same, if you are using
45           Local actions. Alternatively you can use "Path", "Regex", or
46           "Global" to specify a different external path for your action.
47
48       The ACL module currently only knows to exploit the private namespace.
49       In the future extensions may be made to support external namespaces as
50       well.
51
52       Various types of rules are supported, see the list under "RULES".
53
54       When a path is visited, rules are tested one after the other, with the
55       most exact rule fitting the path first, and continuing up the path.
56       Testing continues until a rule explcitly allows or denies access.
57

METHODS

59   allow_access_if
60       Arguments: $path, $rule
61
62       Check the rule condition and allow access to the actions under $path if
63       the rule returns true.
64
65       This is normally useful to allow acces only to a specific part of a
66       tree whose parent has a "deny_access_unless" clause attached to it.
67
68       If the rule test returns false access is not denied or allowed. Instead
69       the next rule in the chain will be checked - in this sense the
70       combinatory behavior of these rules is like logical OR.
71
72   allow_access_if_any
73       Arguments: $path, \@roles
74
75       Same as above for any role in the list.
76
77   deny_access_unless
78       Arguments: $path, $rule
79
80       Check the rule condition and disallow access if the rule returns false.
81
82       This is normally useful to restrict access to any portion of the
83       application unless a certain condition can be met.
84
85       If the rule test returns true access is not allowed or denied. Instead
86       the next rule in the chain will be checked - in this sense the
87       combinatory behavior of these rules is like logical AND.
88
89   deny_access_unless_any
90       Arguments: $path, \@roles
91
92       Same as above for any role in the list.
93
94   allow_access
95   deny_access
96       Arguments: $path
97
98       Unconditionally allow or deny access to a path.
99
100   acl_add_rule
101       Arguments: $path, $rule, [ $filter ]
102
103       Manually add a rule to all the actions under $path using the more
104       flexible (but more verbose) method:
105
106           __PACKAGE__->acl_add_rule(
107               "/foo",
108               sub { ... }, # see FLEXIBLE RULES below
109               sub {
110                   my $action = shift;
111                   # return a true value if you want to apply the rule to this action
112                   # called for all the actions under "/foo"
113               }
114           };
115
116       In this case the rule must be a sub reference (or method name) to be
117       invoked on $c.
118
119       The default filter will skip all actions starting with an underscore,
120       namely "_DISPATCH", "_AUTO", etc (but not "auto", "begin", et al).
121
122   acl_access_denied
123       Arguments: $c, $class, $action, $err
124
125   acl_access_allowed
126       Arguments: $c, $class, $action
127
128       The default event handlers for access denied or allowed conditions. See
129       below on handling access violations.
130
131   acl_allow_root_internals
132       Adds rules that permit access to the root controller (YourApp.pm)
133       "auto", "begin" and "end" unconditionally.
134

EXTENDED METHODS

136   execute
137       The hook for rule evaluation
138
139   setup_actions

RULE EVALUATION

141       When a rule is attached to an action the "distance" from the path it
142       was specified in is recorded. The closer the path is to the rule, the
143       earlier it will be checked.
144
145       Any rule can either explicitly deny or explicitly allow access to a
146       particular action. If a rule does not explicitly allow or permit
147       access, the next rule is checked, until the list of rules is finished.
148       If no rule has determined a policy, access to the path will be
149       permitted.
150

PATHS

152       To apply a rule to an action or group of actions you must supply a
153       path.
154
155       This path is what you should see dumped at the beginning of the
156       Catalyst server's debug output.
157
158       For example, for the "foo" action defined at the root level of your
159       application, specify "/foo". Under the "Moose" controller (e.g.
160       "MyApp::C::Moose", the action "bar" will be "/moose/bar").
161
162       The "distance" a path has from an action that is contained in it is the
163       the difference in the number of slashes between the path of the action,
164       and the path to which the rule was applied.
165

RULES

167   Easy Rules
168       There are several kinds of rules you can create without using the
169       complex interface described in "FLEXIBLE RULES".
170
171       The easy rules are all predicate list oriented. "allow_access_if" will
172       explicitly allow access if the predicate is true, and
173       "deny_access_unless" will explicitly disallow if the predicate is
174       false.
175
176       Role Lists
177             __PACAKGE__->deny_access_unless_any( "/foo/bar", [qw/admin moose_trainer/] );
178
179           When the role is evaluated the
180           Catalyst::Plugin::Authorization::Roles will be used to check
181           whether the currently logged in user has the specified roles.
182
183           If "allow_access_if_any" is used, the presence of any of the roles
184           in the list will immediately permit access, and if
185           "deny_access_unless_any" is used, the lack of all of the roles will
186           immediately deny access.
187
188           Similarly, if "allow_access_if" is used, the presence of all the
189           roles will immediately permit access, and if "deny_access_unless"
190           is used, the lack of any of the roles will immediately deny access.
191
192           When specifying a role list without the
193           Catalyst::Plugin::Authorization::Roles plugin loaded the ACL engine
194           will throw an error.
195
196       Predicate Code Reference / Method Name
197           The code reference or method is invoked with the context and the
198           action objects. The boolean return value will determine the
199           behavior of the rule.
200
201               __PACKAGE__->allow_access_if( "/gorch", sub { ... } );
202               __PACKAGE__->deny_access_unless( "/moose", "method_name" );
203
204           When specifying a method name the rule engine ensures that it can
205           be invoked using "can" in UNIVERSAL.
206
207       Constant
208           You can use "undef", 0 and '' to use as a constant false predicate,
209           or 1 to use as a constant true predicate.
210
211   Flexible Rules
212       These rules are the most annoying to write but provide the most
213       flexibility.
214
215       All access control is performed using exceptions -
216       $Catalyst::Plugin::Authorization::ACL::Engine::DENIED, and
217       $Catalyst::Plugin::Authorization::ACL::Engine::ALLOWED (these can be
218       imported from the engine module).
219
220       If no rule decides to explicitly allow or deny access, access will be
221       permitted.
222
223       Here is a rule that will always break out of rule processing by either
224       explicitly allowing or denying access based on how much mojo the
225       current user has:
226
227           __PACKAGE__->acl_add_rule(
228               "/foo",
229               sub {
230                   my ( $c, $action ) = @_;
231
232                   if ( $c->user->mojo > 50 ) {
233                       die $ALLOWED;
234                   } else {
235                       die $DENIED;
236                   }
237               }
238           );
239

HANDLING DENIAL

241       There are two plugin methods that can be called when a rule makes a
242       decision about an action:
243
244       acl_access_allowed
245           A no-op
246
247       acl_access_denied
248           Looks for a private action named "access_denied" from the denied
249           action's controller and outwards (much like "auto"), and if none is
250           found throws an access denied exception.
251
252       forcibly_allow_access
253           Within an "access_denied" action this will immediately cause the
254           blocked action to be executed anyway.
255
256       This means that you have several alternatives:
257
258   Provide an "access_denied" action
259           package MyApp::Controller::Foo;
260
261           sub access_denied : Private {
262               my ( $self, $c, $action ) = @_;
263
264               ...
265               $c->forcibly_allow_access
266                   if $you->mean_it eq "really";
267           }
268
269       If you call "forcibly_allow_access" then the blocked action will be
270       immediately unblocked. Otherwise the execution of the action will
271       cease, and return to it's caller or end.
272
273   Cleanup in "end"
274           sub end : Private {
275               my ( $self, $c ) = @_;
276
277               if ( $c->error and $c->error->[-1] eq "access denied" ) {
278                   $c->error(0); # clear the error
279
280                   # access denied
281               } else {
282                   # normal end
283               }
284           }
285
286   Override the plugin event handler methods
287           package MyApp;
288
289           sub acl_access_allowed {
290               my ( $c, $class, $action ) = @_;
291               ...
292           }
293
294           sub acl_access_denied {
295               my ( $c, $class, $action, $err ) = @_;
296               ...
297           }
298
299       $class is the controller class the $action object was going to be
300       executed in, and $err is the exception cought during rule evaluation,
301       if any (access is denied if a rule raises an exception).
302

AUTHOR

309       Yuval Kogman <nothingmuch@woobling.org>
310

CONTRIBUTORS

312       castaway: Jess Robinson
313
314       caelum: Rafael Kitover <rkitover@cpan.org>
315

COPYRIGHT & LICENSE

317       Copyright (c) 2005 - 2009 the Catalyst::Plugin::Authorization::ACL
318       "AUTHOR" and "CONTRIBUTORS" as listed above.
319
320       This library is free software; you can redistribute it and/or modify it
321       under the same terms as Perl itself.
322
323
324
325perl v5.30.1                      2020-0C1a-t2a9lyst::Plugin::Authorization::ACL(3)