NAME

Apache2::Access - A Perl API for Apache request object: Access, Authentication and Authorization.

Synopsis

  use Apache2::Access ();
  
  # allow only GET method
  $r->allow_methods(1, qw(GET));
  
  # Apache Options value
  $options = $r->allow_options();
  
  # Apache AllowOverride value
  $allow_override = $r->allow_overrides();
  
  # which Options are allowed by AllowOverride (since Apache 2.2)
  $allow_override_opts = $r->allow_override_opts();
  
  # auth name ("foo bar")
  $auth_name = $r->auth_name();
  
  # auth type
  $auth_type = $r->auth_type();
  $r->auth_type("Digest");
  
  # Basic authentication process
  my ($rc, $passwd) = $r->get_basic_auth_pw();
  
  # the login name of the remote user (RFC1413)
  $remote_logname = $r->get_remote_logname();
  
  # dynamically figure out which auth has failed
  $r->note_auth_failure();
  
  # note Basic auth failure
  $r->note_basic_auth_failure();
  
  # note Digest auth failure
  $r->note_digest_auth_failure();
  
  # Apache Request value(s)
  $requires = $r->requires();
  
  # Apache Satisfy value (as a number)
  $satisfy = $r->satisfies();
  
  # check whether some auth is configured
  $need_auth = $r->some_auth_required();

Description

The API provided by this module deals with access, authentication and authorization phases.

Apache2::Access extends Apache2::RequestRec.

API

Apache2::Access provides the following functions and/or methods:

`allow_methods`

Specify which HTTP methods are allowed

  $r->allow_methods($reset);
  $r->allow_methods($reset, @methods);

obj: $r ( Apache2::RequestRec object ): The current request
arg1: $reset ( boolean ): If a true value is passed all the previously allowed methods are removed. Otherwise the list is left intact.
opt arg2: @methods ( array of strings ): a list of HTTP methods to be allowed (e.g. GET and POST)
ret: no return value
since: 2.0.00

For example: here is how to allow only GET and POST methods, regardless to what was the previous setting:

  $r->allow_methods(1, qw(GET POST));

`allow_options`

Retrieve the value of Options for this request

  $options = $r->allow_options();

obj: $r ( Apache2::RequestRec object ): The current request
ret: $options ( integer ): the Options bitmask. Normally used with bitlogic operators against Apache2::Const :options constants.
since: 2.0.00

For example if the configuration for the current request was:

  Options None
  Options Indexes FollowSymLinks

The following applies:

  use Apache2::Const -compile => qw(:options);
  $r->allow_options & Apache2::Const::OPT_INDEXES;   # TRUE
  $r->allow_options & Apache2::Const::OPT_SYM_LINKS; # TRUE
  $r->allow_options & Apache2::Const::OPT_EXECCGI;   # FALSE

`allow_overrides`

Retrieve the value of AllowOverride for this request

  $allow_override = $r->allow_overrides();

obj: $r ( Apache2::RequestRec object ): The current request
ret: $allow_override ( integer ): the AllowOverride bitmask. Normally used with bitlogic operators against Apache2::Const :override constants.
since: 2.0.00

For example if the configuration for the current request was:

  AllowOverride AuthConfig

The following applies:

  use Apache2::Const -compile => qw(:override);
  $r->allow_overrides & Apache2::Const::OR_AUTHCFG; # TRUE
  $r->allow_overrides & Apache2::Const::OR_LIMIT; # FALSE

`allow_override_opts`

Retrieve the bitmask of allowed Options set by AllowOverride Options=... for this request

  $override_opts = $r->allow_override_opts();

Enabling single options was introduced in Apache 2.2. For Apache 2.0 this function returns Apache2::Const::OPT_UNSET | Apache2::Const::OPT_ALL | Apache2::Const::OPT_INCNOEXEC | Apache2::Const::OPT_SYM_OWNER | Apache2::Const::OPT_MULTI, which corresponds to the default value (if not set) for Apache 2.2.

obj: $r ( Apache2::RequestRec object ): The current request
ret: $override_opts ( integer ): the override options bitmask. Normally used with bitlogic operators against Apache2::Const :options constants.
since: 2.0.3

For example if the configuration for the current request was:

  AllowOverride Options=Indexes,ExecCGI

The following applies:

  use Apache2::Const -compile => qw(:options);
  $r->allow_override_opts & Apache2::Const::OPT_EXECCGI; # TRUE
  $r->allow_override_opts & Apache2::Const::OPT_SYM_LINKS; # FALSE

`auth_name`

Get/set the current Authorization realm (the per directory configuration directive AuthName):

  $auth_name = $r->auth_name();
  $auth_name = $r->auth_name($new_auth_name);

obj: $r ( Apache2::RequestRec object ): The current request
opt arg1: $new_auth_name ( string ): If $new_auth_name is passed a new AuthName value is set
ret: $ ( integer ): The current value of AuthName
since: 2.0.00

The AuthName directive creates protection realm within the server document space. To quote RFC 1945 "These realms allow the protected resources on a server to be partitioned into a set of protection spaces, each with its own authentication scheme and/or authorization database." The client uses the root URL of the server to determine which authentication credentials to send with each HTTP request. These credentials are tagged with the name of the authentication realm that created them. Then during the authentication stage the server uses the current authentication realm, from $r->auth_name, to determine which set of credentials to authenticate.

`auth_type`

Get/set the type of authorization required for this request (the per directory configuration directive AuthType):

  $auth_type = $r->auth_type();
  $auth_type = $r->auth_type($new_auth_type);

obj: $r ( Apache2::RequestRec object ): The current request
opt arg1: $new_auth_type ( string ): If $new_auth_type is passed a new AuthType value is set
ret: $ ( integer ): The current value of AuthType
since: 2.0.00

Normally AuthType would be set to Basic to use the basic authentication scheme defined in RFC 1945, Hypertext Transfer Protocol -- HTTP/1.0. However, you could set to something else and implement your own authentication scheme.

`get_basic_auth_pw`

Get the password from the request headers

  my ($rc, $passwd) = $r->get_basic_auth_pw();

obj: $r ( Apache2::RequestRec object ): The current request
ret1: $rc ( Apache2::Const constant ): Apache2::Const::OK if the $passwd value is set (and assured a correct value in $r->user); otherwise it returns an error code, either Apache2::Const::HTTP_INTERNAL_SERVER_ERROR if things are really confused, Apache2::Const::HTTP_UNAUTHORIZED if no authentication at all seemed to be in use, or Apache2::Const::DECLINED if there was authentication, but it wasn't Basic (in which case, the caller should presumably decline as well).
ret2: $ret (string): The password as set in the headers (decoded)
since: 2.0.00

If AuthType is not set, this handler first sets it to Basic.

`get_remote_logname`

Retrieve the login name of the remote user (RFC1413)

  $remote_logname = $r->get_remote_logname();

obj: $r ( Apache2::RequestRec object ): The current request
ret: $remote_logname ( string ): The username of the user logged in to the client machine, or an empty string if it could not be determined via RFC1413, which involves querying the client's identd or auth daemon.
since: 2.0.00

Do not confuse this method with $r->user, which provides the username provided by the user during the server authentication.

`note_auth_failure`

Setup the output headers so that the client knows how to authenticate itself the next time, if an authentication request failed. This function works for both basic and digest authentication

  $r->note_auth_failure();

obj: $r ( Apache2::RequestRec object ): The current request
ret: no return value
since: 2.0.00

This method requires AuthType to be set to Basic or Digest. Depending on the setting it'll call either $r->note_basic_auth_failure or $r->note_digest_auth_failure.

`note_basic_auth_failure`

Setup the output headers so that the client knows how to authenticate itself the next time, if an authentication request failed. This function works only for basic authentication

  $r->note_basic_auth_failure();

obj: $r ( Apache2::RequestRec object ): The current request
ret: no return value
since: 2.0.00

`note_digest_auth_failure`

Setup the output headers so that the client knows how to authenticate itself the next time, if an authentication request failed. This function works only for digest authentication.

  $r->note_digest_auth_failure();

obj: $r ( Apache2::RequestRec object ): The current request
ret: no return value
since: 2.0.00

`requires`

Retrieve information about all of the requires directives for this request

  $requires = $r->requires

obj: $r ( Apache2::RequestRec object ): The current request
ret: $requires ( ARRAY ref ): Returns an array reference of hash references, containing information related to the require directive.
since: 2.0.00

This is normally used for access control.

For example if the configuration had the following require directives:

    Require user  goo bar
    Require group bar tar

this method will return the following datastructure:

  [
    {
      'method_mask' => -1,
      'requirement' => 'user goo bar'
    },
    {
      'method_mask' => -1,
      'requirement' => 'group bar tar'
    }
  ];

The requirement field is what was passed to the Require directive. The method_mask field is a bitmask which can be modified by the Limit directive, but normally it can be safely ignored as it's mostly used internally. For example if the configuration was:

    Require user goo bar
    Require group bar tar
    <Limit POST>
       Require valid-user
    </Limit>

and the request method was POST, $r->requires will return:

  [
    {
      'method_mask' => -1,
      'requirement' => 'user goo bar'
    },
    {
      'method_mask' => -1,
      'requirement' => 'group bar tar'
    }
    {
      'method_mask' => 4,
      'requirement' => 'valid-user'
    }
  ];

But if the request method was GET, it will return only:

  [
    {
      'method_mask' => -1,
      'requirement' => 'user goo bar'
    },
    {
      'method_mask' => -1,
      'requirement' => 'group bar tar'
    }
  ];

As you can see Apache gives you the requirements relevant for the current request, so the method_mask is irrelevant.

It is also a good time to remind that in the general case, access control directives should not be placed within a <Limit> section. Refer to the Apache documentation for more information.

Using the same configuration and assuming that the request was of type POST, the following code inside an Auth handler:

  my %require =
      map { my ($k, $v) = split /\s+/, $_->{requirement}, 2; ($k, $v||'') }
      @{ $r->requires };

will populate %require with the following pairs:

  'group' => 'bar tar',
  'user' => 'goo bar',
  'valid-user' => '',

`satisfies`

How the requires lines must be met. What's the applicable value of the Satisfy directive:

  $satisfy = $r->satisfies();

obj: $r ( Apache2::RequestRec object )

The current request

ret: $satisfy ( integer )

How the requirements must be met. One of the Apache2::Const :satisfy constants:

Apache2::Const::SATISFY_ANY, Apache2::Const::SATISFY_ALL and Apache2::Const::SATISFY_NOSPEC.

since: 2.0.00

See the documentation for the Satisfy directive in the Apache documentation.

`some_auth_required`

Can be used within any handler to determine if any authentication is required for the current request:

  $need_auth = $r->some_auth_required();

obj: $r ( Apache2::RequestRec object ): The current request
ret: $need_auth ( boolean ): TRUE if authentication is required, FALSE otherwise
since: 2.0.00

Copyright

mod_perl 2.0 and its core modules are copyrighted under The Apache Software License, Version 2.0.

Authors

The mod_perl development team and numerous contributors.