Provided by: policykit-1_0.102-1_i386 bug

NAME

       polkit - Authorization Framework

OVERVIEW

       PolicyKit provides an authorization API intended to be used by
       privileged programs ("MECHANISMS") offering service to unprivileged
       programs ("CLIENTS") through some form of IPC mechanism such as D-Bus
       or Unix pipes. In this scenario, the mechanism typically treats the
       client as untrusted. For every request from a client, the mechanism
       needs to determine if the request is authorized or if it should refuse
       to service the client. Using the PolicyKit API, a mechanism can offload
       this decision to a trusted party: The PolicyKit Authority.

       In addition to acting as an authority, PolicyKit allows users to obtain
       temporary authorization through authenticating either an administrative
       user or the owner of the session the client belongs to. This is useful
       for scenarios where a mechanism needs to verify that the operator of
       the system really is the user or really is an administrative user.

SYSTEM ARCHITECTURE

       The system architecture of PolicyKit is comprised of the Authority
       (implemented as a service on the system message bus) and a
       Authentication Agent per user session (provided and started by the user
       session e.g. GNOME or KDE). Additionally, PolicyKit supports a number
       of extension points - specifically, vendors and/or sites can write
       extensions to completely control authorization policy. In a block
       diagram, the architecture looks like this:

           [IMAGE][1]

                +-------------------+
                |   Authentication  |
                |       Agent       |
                +-------------------+
                | libpolkit-agent-1 |
                +-------------------+
                       ^                                  +--------+
                       |                                  | Client |
                       +--------------+                   +--------+
                                      |                        ^
                                      |                        |
               User Session           |                        |
               =======================|========================|=============
               System Context         |                        |
                                      |                        |
                                      |                    +---+
                                      V                    |
                                    /------------\         |
                                    | System Bus |         |
                                    \------------/         |
                                      ^        ^           V
                                      |        |      +---------------------+
                       +--------------+        |      |      Mechanism      |
                       |                       |      +---------------------+
                       V                       +----> | libpolkit-gobject-1 |
               +------------------+                   +---------------------+
               | org.freedesktop. |
               |    PolicyKit1    |
               +------------------+
               |   Backends and   |
               |    Extensions    |
               +------------------+

       For convenience, the libpolkit-gobject-1 library wraps the PolicyKit
       D-Bus API using GObject. However, a mechanism can also use the D-Bus
       API or the pkcheck(1) command to check authorizations.

       The libpolkit-agent-1 library provides an abstraction of the native
       authentication system, e.g.  pam(8) and also facilities registration
       and communication with the PolicyKit D-Bus service.

       PolicyKit extensions and authority backends are implemented using the
       libpolkit-backend-1 library.

       See the developer documentation[2] for more information about using and
       extending PolicyKit.

       See pklocalauthority(8) for information about the Local Authority - the
       default authority implementation shipped with PolicyKit.

AUTHENTICATION AGENTS

       An authentication agent is used to make the user of a session prove
       that the user of the session really is the user (by authenticating as
       the user) or an administrative user (by authenticating as a
       administrator). In order to integrate well with the rest of the user
       session (e.g. match the look and feel), authentication agents are meant
       to be provided by the user session that the user uses. For example, an
       authentication agent may look like this:

           [IMAGE][3]

               +----------------------------------------------------------+
               |                     Authenticate                     [X] |
               +----------------------------------------------------------+
               |                                                          |
               |  [Icon]  Authentication is required to run ATA SMART     |
               |          self tests                                      |
               |                                                          |
               |          An application is attempting to perform an      |
               |          action that requires privileges. Authentication |
               |          as the super user is required to perform this   |
               |          action.                                         |
               |                                                          |
               |          Password for root: [_________________________]  |
               |                                                          |
               | [V] Details:                                             |
               |  Drive:  ATA INTEL SSDSA2MH08 (045C)                     |
               |  Device: /dev/sda                                        |
               |  Action: org.fd.devicekit.disks.drive-ata-smart-selftest |
               |  Vendor: The DeviceKit Project                           |
               |                                                          |
               |                                  [Cancel] [Authenticate] |
               +----------------------------------------------------------+

       If the system is configured without a root account it may allow you to
       select the administrative user who is authenticating:

           [IMAGE][4]

               +----------------------------------------------------------+
               |                     Authenticate                     [X] |
               +----------------------------------------------------------+
               |                                                          |
               |  [Icon]  Authentication is required to run ATA SMART     |
               |          self tests                                      |
               |                                                          |
               |          An application is attempting to perform an      |
               |          action that requires privileges. Authentication |
               |          as one of the users below is required to        |
               |          perform this action.                            |
               |                                                          |
               |          [[Face] Patrick Bateman (bateman)         [V]]  |
               |                                                          |
               |          Password for bateman: [______________________]  |
               |                                                          |
               | [V] Details:                                             |
               |  Drive:  ATA INTEL SSDSA2MH08 (045C)                     |
               |  Device: /dev/sda                                        |
               |  Action: org.fd.devicekit.disks.drive-ata-smart-selftest |
               |  Vendor: The DeviceKit Project                           |
               |                                                          |
               |                                  [Cancel] [Authenticate] |
               +----------------------------------------------------------+

       See pklocalauthority(8) on how to set up the local authority
       implemention for systems without a root account.

DECLARING ACTIONS

       A mechanism need to declare a set of "ACTIONS" in order to use
       PolicyKit. Actions correspond to operations that clients can request
       the mechanism to carry out and are defined in XML files that the
       mechanism installs into the /usr/share/polkit-1/actions directory.

       PolicyKit actions are namespaced and can only contain the characters
       [a-z][0-9].- e.g. lower-case ASCII, digits, period and hyphen. Each XML
       file can contain more than one action but all actions need to be in the
       same namespace and the file needs to be named after the namespace and
       have the extension .policy.

       The XML file must have the following doctype declaration

           <?xml version="1.0" encoding="UTF-8"?>
           <!DOCTYPE policyconfig PUBLIC "-//freedesktop//DTD PolicyKit Policy Configuration 1.0//EN"
           "http://www.freedesktop.org/standards/PolicyKit/1.0/policyconfig.dtd">

       The policyconfig element must be present exactly once. Elements that
       can be used inside policyconfig includes:

       vendor
           The name of the project or vendor that is supplying the actions in
           the XML document. Optional.

       vendor_url
           A URL to the project or vendor that is supplying the actions in the
           XML document. Optional.

       icon_name
           An icon representing the project or vendor that is supplying the
           actions in the XML document. The icon name must adhere to the
           Freedesktop.org Icon Naming Specification[5]. Optional.

       action
           Declares an action. The action name is specified using the id
           attribute and can only contain the characters [a-z][0-9].- e.g.
           lower-case ASCII, digits, period and hyphen.

       Elements that can be used inside action includes:

       description
           A human readable description of the action, e.g.  "Install unsigned
           software".

       message
           A human readable message displayed to the user when asking for
           credentials when authentication is needed, e.g.  "Installing
           unsigned software requires authentication".

       defaults
           This element is used to specify implicit authorizations for
           clients.

           Elements that can be used inside defaults includes:

           allow_any
               Implicit authorizations that apply to any client. Optional.

           allow_inactive
               Implicit authorizations that apply to clients in inactive
               sessions on local consoles. Optional.

           allow_active
               Implicit authorizations that apply to clients in active
               sessions on local consoles. Optional.

           Each of the allow_any, allow_inactive and allow_active elements can
           contain the following values:

           no
               Not authorized.

           yes
               Authorized.

           auth_self
               Authentication by the owner of the session that the client
               originates from is required.

           auth_admin
               Authentication by an administrative user is required.

           auth_self_keep
               Like auth_self but the authorization is kept for a brief
               period.

           auth_admin_keep
               Like auth_admin but the authorization is kept for a brief
               period.

       annotate
           Used for annotating an action with a key/value pair. The key is
           specified using the the key attribute and the value is specified
           using the value attribute. This element may appear zero or more
           times. See pkexec(1) for an example of how this can be used.

       vendor
           Used for overriding the vendor on a per-action basis. Optional.

       vendor_url
           Used for overriding the vendor URL on a per-action basis. Optional.

       icon_name
           Used for overriding the icon name on a per-action basis. Optional.

       For localization, description and message elements may occur multiple
       times with different xml:lang attributes.

       To list installed PolicyKit actions, use the pkaction(1) command.

AUTHOR

       Written by David Zeuthen davidz@redhat.com with a lot of help from many
       others.

BUGS

       Please send bug reports to either the distribution or the polkit-devel
       mailing list, see the link
       http://lists.freedesktop.org/mailman/listinfo/polkit-devel on how to
       subscribe.

SEE ALSO

       pklocalauthority(8) polkitd(8) pkaction(1), pkcheck(1), pkexec(1),

NOTES

        1. /usr/share/gtk-doc/html/polkit-1/polkit-architecture.png

        2. developer documentation
           file:///usr/share/gtk-doc/html/polkit-1/index.html

        3. /usr/share/gtk-doc/html/polkit-1/polkit-authentication-agent-
           example.png

        4. /usr/share/gtk-doc/html/polkit-1/polkit-authentication-agent-
           example-wheel.png

        5. Freedesktop.org Icon Naming Specification
           http://standards.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html