view release on metacpan or  search on metacpan

lib/Apache/ASP/StateManager.pm  view on Meta::CPAN

	
	# cookieless session support, cascading values
	$self->{session_url_parse_match} = &config($self, 'SessionQueryParseMatch');
	$self->{session_url_parse} = $self->{session_url_parse_match} || &config($self, 'SessionQueryParse');
	$self->{session_url_match} = $self->{session_url_parse_match} || &config($self, 'SessionQueryMatch');
	$self->{session_url} = $self->{session_url_parse} || $self->{session_url_match} || &config($self, 'SessionQuery');
	$self->{session_url_force} = &config($self, 'SessionQueryForce');
	
	$self->{session_serialize} = &config($self, 'SessionSerialize');
	$self->{secure_session}    = &config($self, 'SecureSession');
	$self->{http_only_session} = &config($self, 'HTTPOnlySession');
	# session timeout in seconds since that is what we work with internally
	$self->{session_timeout}   = &config($self, 'SessionTimeout', undef, $SessionTimeout) * 60;
	$self->{'ua'}              = $self->{headers_in}->get('User-Agent') || 'UNKNOWN UA';
	# refresh group by some increment smaller than session timeout
	# to withstand DoS, bruteforce guessing attacks
	# defaults to checking the group once every 2 minutes
	$self->{group_refresh}     = int($self->{session_timeout} / $self->{state_manager});
	
	# Session state is dependent on internal state

	# load at runtime for CGI environments, preloaded for mod_perl
	require Apache::ASP::Session;

	$session = $self->{Session} = &Apache::ASP::Session::new($self)
	  || $self->Die("can't create session");
	$self->{state_serialize} && $session->Lock();
	
    } else {
	$self->{dbg} && $self->Debug("no sessions allowed config");
    }

    # update after long state init, possible with SessionSerialize config
    $self->{Response}->IsClientConnected();

    # POSTPOSE STATE EVENTS, so we can delay the Response object creation
    # until after the state objects are created
    if($session) {
	my $last_session_timeout;
	if($session->Started()) {
	    # we only want one process purging at a time
	    if($self->{app_state}) {
		$internal->LOCK();
		if(($last_session_timeout = $internal->{LastSessionTimeout} || 0) < time()) {
		    $internal->{'LastSessionTimeout'} = $self->{session_timeout} + time;
		    $internal->UNLOCK();
		    $self->{Application}->Lock;
		    my $obj = tied(%{$self->{Application}});
		    if($self->CleanupGroups('PURGE')) {
			$last_session_timeout && $global_asa->ApplicationOnEnd();
			$global_asa->ApplicationOnStart();
		    }
		    $self->{Application}->UnLock;
		} 
		$internal->UNLOCK();
	    }
	    $global_asa->SessionOnStart();
	}

	if($self->{app_state}) {
	    # The last session timeout should only be updated every group_refresh period
	    # another optimization, rand() so not all at once either
	    $internal->LOCK();
	    $last_session_timeout ||= $internal->{'LastSessionTimeout'};
	    if($last_session_timeout < $self->{session_timeout} + time + 
	       (rand() * $self->{group_refresh} / 2)) 
	      {
		  $self->{dbg} && $self->Debug("updating LastSessionTimeout from $last_session_timeout");
		  $internal->{'LastSessionTimeout'} = 
		    $self->{session_timeout} + time() + $self->{group_refresh};
	      }
	    $internal->UNLOCK();
	}
    }

    $self;
}

# Cleanup a state group, by default the group of the current session
# We do this currently in DESTROY, which happens after the current
# script has been executed, so that cleanup doesn't happen until
# after output to user
#
# We always exit unless there is a $Session defined, since we only 
# cleanup groups of sessions if sessions are allowed for this script
sub CleanupGroup {
    my($self, $group_id, $force) = @_;
    return unless $self->{Session};

    my $asp = $self; # bad hack for some moved around code
    $force ||= 0;

    # GET GROUP_ID
    my $state;
    unless($group_id) {
	$state = $self->{Session}{_STATE};
	$group_id = $state->GroupId();
    }

    # we must have a group id to work with
    $asp->Error("no group id") unless $group_id;
    my $group_key = "GroupId" . $group_id;

    # cleanup timed out sessions, from current group
    my $internal = $asp->{Internal};
    $internal->LOCK();
    my $group_check = $internal->{$group_key} || 0;
    unless($force || ($group_check < time())) {
	$internal->UNLOCK();
	return;
    }
    
    # set the next group_check, randomize a bit to unclump the group checks,
    # for 20 minute session timeout, had rand() / 2 + .5, but it was still
    # too clumpy, going with pure rand() now, even if a bit less efficient

    my $next_check = int($asp->{group_refresh} * rand()) + 1;
    $internal->{$group_key} = time() + $next_check;
    $internal->UNLOCK();

    ## GET STATE for group