Provided by: dacs_1.4.28b-3ubuntu2_i386 bug


       dacs_signout - DACS signout service


       dacs_signout [dacsoptions[1]]


       This web service is part of the DACS suite.

       The dacs_signout web service is invoked from a web browser to cause one
       or more sets of DACS credentials for the current federation[2], stored
       as HTTP cookies, to be removed from the browser. This is done by
       replacing one or more existing cookies with cookies that have expired.
       The effect is that the user agent signs out (logs off) identities
       previously obtained through dacs_authenticate(8)[3] or any other DACS
       authentication method. A DACS-enabled portal will typically provide
       users with a link or web page form to invoke this service.

       By default, all credentials are removed, but credentials can be
       selected for deletion based on a particular username (who the user was
       authenticated as) or a particular jurisdiction (the jurisdiction that
       performed that authentication).

       Should copies of the selected credentials exist outside of the browser,
       they may still be valid; only the browser's copies are destroyed.

       The SIGNOUT_HANDLER[4] directive can optionally be used to specify
       where the user should be redirected before this service terminates,
       provided FORMAT does not select a variety of XML output (see
       dacs.conf(5)[5]). If XML output is selected, a document conforming to
       dacs_current_credentials.dtd[6] is returned.

       Explicitly signing off using this web service is generally unnecessary
       because DACS credentials will either become invalid when their lifetime
       is reached (see AUTH_CREDENTIALS_DEFAULT_LIFETIME_SECS[7]) or will be
       automatically deleted when the user's browser session terminates (or a
       session with a trusted servlet ends). A user can also sign off by
       deleting his browser's DACS cookies. Middleware can simply discard

       As DACS credentials are relative to a particular federation of DACS
       servers, only those credentials that are associated with the federation
       of the DACS server that receives the service request will be affected
       by this service. This implies that a user who wants to explicitly sign
       out must do so for each federation in which he or she is currently

   Web Service Arguments
       In addition to the standard CGI arguments[8], dacs_signout understands
       the following CGI arguments:

           If present, all credentials associated with this username will be
           deleted. If not provided, the username in the credentials is

           If present, all credentials associated with this jurisdiction
           (given as its JURISDICTION_NAME[9]) will be deleted. If not
           provided, the jurisdiction in the credentials is immaterial.

           This optional parameter is as described for the
           dacs_authenticate(8)[3] service.

       The optional parameters are used to delete only those credentials that
       match a particular username or jurisdiction (or both). If neither
       parameter is specified in the service request, all DACS cookies
       associated with the federation that receives the service request will
       be deleted.

       The name matching method can be configured through the NAME_COMPARE[10]

           DACS does not currently provide an inactivity timeout feature, but
           it may appear in a future release. One way to add it would be to
           take advantage of the user tracking[11] capability, which can
           record all of a user's requests for DACS-wrapped services within a
           federation. By simply comparing the current time with the time
           stamp of the user's last service request, the user's idle time can
           be determined. If the idle time exceeds a configured maximum,
           dacs_acs(8)[12] would consider the user's credentials to be invalid
           (effectively expired) and take appropriate action. A
           straightforward implementation would be a relatively simple
           enhancement to DACS; its main drawback, for those that enable it,
           is the extra performance hit incurred from user tracking and having
           to compute idle time during access control processing - whether
           this hit is significant will depend on your platforms, the
           configuration of your federation, and user activity patterns.


       To signout from all identities in the EXAMPLE federation, a user would
       simply invoke a URL like:


       To signout only from the identity EXAMPLE::FEDROOT:bobo, a URL like the
       following might be invoked:


       To signout from only those identities in the EXAMPLE federation having
       a username component bobo, invoke a URL like:


       This would signoff from EXAMPLE::FEDROOT:bobo and EXAMPLE::DSS:bobo,
       for instance.


       The program exits 0 if everything was fine, 1 if an error occurred.


       dacs_authenticate(8)[3], dacs_current_credentials(8)[13],
       dacs_auth_agent(8)[14], dacs_auth_transfer(8)[15],
       dacs_select_credentials(8)[16], dacsauth(1)[17], dacscred(1)[18]

       The DACS distribution includes an example of a "log off" web page:


       Distributed Systems Software ([20])


       Copyright2003-2012 Distributed Systems Software. See the LICENSE[21]
       file that accompanies the distribution for licensing information.


        1. dacsoptions

        2. current federation

        3. dacs_authenticate(8)


        5. dacs.conf(5)

        6. dacs_current_credentials.dtd


        8. standard CGI arguments


       10. NAME_COMPARE

       11. user tracking

       12. dacs_acs(8)

       13. dacs_current_credentials(8)

       14. dacs_auth_agent(8)

       15. dacs_auth_transfer(8)

       16. dacs_select_credentials(8)

       17. dacsauth(1)

       18. dacscred(1)

       19. html/examples/signout.html


       21. LICENSE