use Catalyst::Exception ();
use Digest ();
use overload ();
+use Object::Signature ();
+use Carp;
-our $VERSION = "0.01";
+our $VERSION = '0.20';
+my @session_data_accessors; # used in delete_session
BEGIN {
- __PACKAGE__->mk_accessors(qw/sessionid session_delete_reason/);
+ __PACKAGE__->mk_accessors(
+ "_session_delete_reason",
+ @session_data_accessors = qw/
+ _sessionid
+ _session
+ _session_expires
+ _extended_session_expires
+ _session_data_sig
+ _flash
+ _flash_keep_keys
+ _flash_key_hashes
+ _tried_loading_session_id
+ _tried_loading_session_data
+ _tried_loading_session_expires
+ _tried_loading_flash_data
+ /
+ );
}
sub setup {
%$cfg = (
expires => 7200,
- verify_address => 1,
+ verify_address => 0,
%$cfg,
);
$c->NEXT::setup_session();
}
+sub prepare_action {
+ my $c = shift;
+
+ if ( $c->config->{session}{flash_to_stash}
+ and $c->sessionid
+ and my $flash_data = $c->flash )
+ {
+ @{ $c->stash }{ keys %$flash_data } = values %$flash_data;
+ }
+
+ $c->NEXT::prepare_action(@_);
+}
+
+sub finalize_headers {
+ my $c = shift;
+
+ # fix cookie before we send headers
+ $c->_save_session_expires;
+
+ return $c->NEXT::finalize_headers(@_);
+}
+
sub finalize {
my $c = shift;
+ my $ret = $c->NEXT::finalize(@_);
+
+ # then finish the rest
+ $c->finalize_session;
+ return $ret;
+}
- if ( $c->{session} ) {
+sub finalize_session {
+ my $c = shift;
- # all sessions are extended at the end of the request
- my $now = time;
- @{ $c->{session} }{qw/__updated __expires/} =
- ( $now, $c->config->{session}{expires} + $now );
- $c->store_session_data( $c->sessionid, $c->{session} );
+ $c->NEXT::finalize_session;
+
+ $c->_save_session_id;
+ $c->_save_session;
+ $c->_save_flash;
+
+ $c->_clear_session_instance_data;
+}
+
+sub _save_session_id {
+ my $c = shift;
+
+ # we already called set when allocating
+ # no need to tell the state plugins anything new
+}
+
+sub _save_session_expires {
+ my $c = shift;
+
+ if ( defined($c->_session_expires) ) {
+ my $expires = $c->session_expires; # force extension
+
+ my $sid = $c->sessionid;
+ $c->store_session_data( "expires:$sid" => $expires );
}
+}
+
+sub _save_session {
+ my $c = shift;
+
+ if ( my $session_data = $c->_session ) {
- $c->NEXT::finalize(@_);
+ no warnings 'uninitialized';
+ if ( Object::Signature::signature($session_data) ne
+ $c->_session_data_sig )
+ {
+ $session_data->{__updated} = time();
+ my $sid = $c->sessionid;
+ $c->store_session_data( "session:$sid" => $session_data );
+ }
+ }
}
-sub prepare_action {
+sub _save_flash {
my $c = shift;
- if ( my $sid = $c->sessionid ) {
- my $s = $c->{session} ||= $c->get_session_data($sid);
- if ( !$s or $s->{__expires} < time ) {
+ if ( my $flash_data = $c->_flash ) {
- # session expired
- $c->log->debug("Deleting session $sid (expired)") if $c->debug;
- $c->delete_session("session expired");
+ my $hashes = $c->_flash_key_hashes || {};
+ my $keep = $c->_flash_keep_keys || {};
+ foreach my $key ( keys %$hashes ) {
+ if ( !exists $keep->{$key} and Object::Signature::signature( \$flash_data->{$key} ) eq $hashes->{$key} ) {
+ delete $flash_data->{$key};
+ }
}
- elsif ($c->config->{session}{verify_address}
- && $c->{session}{__address}
- && $c->{session}{__address} ne $c->request->address )
- {
- $c->log->warn(
- "Deleting session $sid due to address mismatch ("
- . $c->{session}{__address} . " != "
- . $c->request->address . ")",
- );
- $c->delete_session("address mismatch");
+
+ my $sid = $c->sessionid;
+
+ if (%$flash_data) {
+ $c->store_session_data( "flash:$sid", $flash_data );
}
else {
+ $c->delete_session_data("flash:$sid");
+ }
+ }
+}
+
+sub _load_session_expires {
+ my $c = shift;
+ return $c->_session_expires if $c->_tried_loading_session_expires;
+ $c->_tried_loading_session_expires(1);
+
+ if ( my $sid = $c->sessionid ) {
+ my $expires = $c->get_session_data("expires:$sid") || 0;
+
+ if ( $expires >= time() ) {
+ $c->_session_expires( $expires );
+ return $expires;
+ } else {
+ $c->delete_session( "session expired" );
+ return 0;
+ }
+ }
+
+ return;
+}
+
+sub _load_session {
+ my $c = shift;
+ return $c->_session if $c->_tried_loading_session_data;
+ $c->_tried_loading_session_data(1);
+
+ if ( my $sid = $c->sessionid ) {
+ if ( $c->_load_session_expires ) { # > 0
+
+ my $session_data = $c->get_session_data("session:$sid") || return;
+ $c->_session($session_data);
+
+ no warnings 'uninitialized'; # ne __address
+ if ( $c->config->{session}{verify_address}
+ && $session_data->{__address} ne $c->request->address )
+ {
+ $c->log->warn(
+ "Deleting session $sid due to address mismatch ("
+ . $session_data->{__address} . " != "
+ . $c->request->address . ")"
+ );
+ $c->delete_session("address mismatch");
+ return;
+ }
+
$c->log->debug(qq/Restored session "$sid"/) if $c->debug;
+ $c->_session_data_sig( Object::Signature::signature($session_data) ) if $session_data;
+ $c->_expire_session_keys;
+
+ return $session_data;
}
}
- $c->NEXT::prepare_action(@_);
+ return;
+}
+
+sub _load_flash {
+ my $c = shift;
+ return $c->_flash if $c->_tried_loading_flash_data;
+ $c->_tried_loading_flash_data(1);
+
+ if ( my $sid = $c->sessionid ) {
+ if ( my $flash_data = $c->_flash
+ || $c->_flash( $c->get_session_data("flash:$sid") ) )
+ {
+ $c->_flash_key_hashes({ map { $_ => Object::Signature::signature( \$flash_data->{$_} ) } keys %$flash_data });
+
+ return $flash_data;
+ }
+ }
+
+ return;
+}
+
+sub _expire_session_keys {
+ my ( $c, $data ) = @_;
+
+ my $now = time;
+
+ my $expire_times = ( $data || $c->_session || {} )->{__expire_keys} || {};
+ foreach my $key ( grep { $expire_times->{$_} < $now } keys %$expire_times ) {
+ delete $c->_session->{$key};
+ delete $expire_times->{$key};
+ }
+}
+
+sub _clear_session_instance_data {
+ my $c = shift;
+ $c->$_(undef) for @session_data_accessors;
+ $c->NEXT::_clear_session_instance_data; # allow other plugins to hook in on this
}
sub delete_session {
my ( $c, $msg ) = @_;
+ $c->log->debug("Deleting session" . ( defined($msg) ? "($msg)" : '(no reason given)') ) if $c->debug;
+
# delete the session data
- my $sid = $c->sessionid;
- $c->delete_session_data($sid);
+ if ( my $sid = $c->sessionid ) {
+ $c->delete_session_data("${_}:${sid}") for qw/session expires flash/;
+ $c->delete_session_id($sid);
+ }
# reset the values in the context object
- $c->{session} = undef;
- $c->sessionid(undef);
- $c->session_delete_reason($msg);
+ # see the BEGIN block
+ $c->_clear_session_instance_data;
+
+ $c->_session_delete_reason($msg);
+}
+
+sub session_delete_reason {
+ my $c = shift;
+
+ $c->session_is_valid; # check that it was loaded
+
+ $c->_session_delete_reason(@_);
+}
+
+sub session_expires {
+ my $c = shift;
+
+ if ( defined( my $expires = $c->_extended_session_expires ) ) {
+ return $expires;
+ } elsif ( defined( $expires = $c->_load_session_expires ) ) {
+ return $c->extend_session_expires( $expires );
+ } else {
+ return 0;
+ }
+}
+
+sub extend_session_expires {
+ my ( $c, $expires ) = @_;
+ $c->_extended_session_expires( my $updated = $c->calculate_extended_session_expires( $expires ) );
+ $c->extend_session_id( $c->sessionid, $updated );
+ return $updated;
+}
+
+sub calculate_initial_session_expires {
+ my $c = shift;
+ return ( time() + $c->config->{session}{expires} );
+}
+
+sub calculate_extended_session_expires {
+ my ( $c, $prev ) = @_;
+ $c->calculate_initial_session_expires;
+}
+
+sub reset_session_expires {
+ my ( $c, $sid ) = @_;
+
+ my $exp = $c->calculate_initial_session_expires;
+ $c->_session_expires( $exp );
+ $c->_extended_session_expires( $exp );
+ $exp;
+}
+
+sub sessionid {
+ my $c = shift;
+
+ return $c->_sessionid || $c->_load_sessionid;
+}
+
+sub _load_sessionid {
+ my $c = shift;
+ return if $c->_tried_loading_session_id;
+ $c->_tried_loading_session_id(1);
+
+ if ( defined( my $sid = $c->get_session_id ) ) {
+ if ( $c->validate_session_id($sid) ) {
+ # temporarily set the inner key, so that validation will work
+ $c->_sessionid($sid);
+ return $sid;
+ } else {
+ my $err = "Tried to set invalid session ID '$sid'";
+ $c->log->error($err);
+ Catalyst::Exception->throw($err);
+ }
+ }
+
+ return;
+}
+
+sub session_is_valid {
+ my $c = shift;
+
+ # force a check for expiry, but also __address, etc
+ if ( $c->_load_session ) {
+ return 1;
+ } else {
+ return;
+ }
+}
+
+sub validate_session_id {
+ my ( $c, $sid ) = @_;
+
+ $sid and $sid =~ /^[a-f\d]+$/i;
}
sub session {
my $c = shift;
- return $c->{session} if $c->{session};
+ $c->_session || $c->_load_session || do {
+ $c->create_session_id_if_needed;
+ $c->initialize_session_data;
+ };
+}
- my $sid = $c->generate_session_id;
- $c->sessionid($sid);
+sub keep_flash {
+ my ( $c, @keys ) = @_;
+ my $href = $c->_flash_keep_keys || $c->_flash_keep_keys({});
+ (@{$href}{@keys}) = ((undef) x @keys);
+}
- $c->log->debug(qq/Created session "$sid"/) if $c->debug;
+sub _flash_data {
+ my $c = shift;
+ $c->_flash || $c->_load_flash || do {
+ $c->create_session_id_if_needed;
+ $c->_flash( {} );
+ };
+}
- return $c->initialize_session_data;
+sub _set_flash {
+ my $c = shift;
+ if (@_) {
+ my $items = @_ > 1 ? {@_} : $_[0];
+ croak('flash takes a hash or hashref') unless ref $items;
+ @{ $c->_flash }{ keys %$items } = values %$items;
+ }
}
-sub initialize_session_data {
+sub flash {
my $c = shift;
+ $c->_flash_data;
+ $c->_set_flash(@_);
+ return $c->_flash;
+}
+
+sub clear_flash {
+ my $c = shift;
+
+ #$c->delete_session_data("flash:" . $c->sessionid); # should this be in here? or delayed till finalization?
+ $c->_flash_key_hashes({});
+ $c->_flash_keep_keys({});
+ $c->_flash({});
+}
+
+sub session_expire_key {
+ my ( $c, %keys ) = @_;
my $now = time;
+ @{ $c->session->{__expire_keys} }{ keys %keys } =
+ map { $now + $_ } values %keys;
+}
- return $c->{session} = {
- __created => $now,
- __updated => $now,
- __expires => $now + $c->config->{session}{expires},
+sub initialize_session_data {
+ my $c = shift;
- (
- $c->config->{session}{verify_address}
- ? ( __address => $c->request->address )
- : ()
- ),
- };
+ my $now = time;
+
+ return $c->_session(
+ {
+ __created => $now,
+ __updated => $now,
+
+ (
+ $c->config->{session}{verify_address}
+ ? ( __address => $c->request->address )
+ : ()
+ ),
+ }
+ );
}
sub generate_session_id {
return $digest->hexdigest;
}
+sub create_session_id_if_needed {
+ my $c = shift;
+ $c->create_session_id unless $c->sessionid;
+}
+
+sub create_session_id {
+ my $c = shift;
+
+ my $sid = $c->generate_session_id;
+
+ $c->log->debug(qq/Created session "$sid"/) if $c->debug;
+
+ $c->_sessionid($sid);
+ $c->reset_session_expires;
+ $c->set_session_id($sid);
+
+ return $sid;
+}
+
my $counter;
sub session_hash_seed {
sub _find_digest () {
unless ($usable) {
- foreach my $alg (qw/SHA-1 MD5 SHA-256/) {
- eval {
- my $obj = Digest->new($alg);
+ foreach my $alg (qw/SHA-1 SHA-256 MD5/) {
+ if ( eval { Digest->new($alg) } ) {
$usable = $alg;
- return $obj;
- };
+ last;
+ }
}
- $usable
- or Catalyst::Exception->throw(
+ Catalyst::Exception->throw(
"Could not find a suitable Digest module. Please install "
- . "Digest::SHA1, Digest::SHA, or Digest::MD5" );
+ . "Digest::SHA1, Digest::SHA, or Digest::MD5" )
+ unless $usable;
}
return Digest->new($usable);
);
}
+
+sub get_session_id { shift->NEXT::get_session_id(@_) }
+sub set_session_id { shift->NEXT::set_session_id(@_) }
+sub delete_session_id { shift->NEXT::delete_session_id(@_) }
+sub extend_session_id { shift->NEXT::extend_session_id(@_) }
+
__PACKAGE__;
__END__
=head1 NAME
-Catalyst::Plugin::Session - Generic Session plugin - ties together server side
-storage and client side tickets required to maintain session data.
+Catalyst::Plugin::Session - Generic Session plugin - ties together server side storage and client side state required to maintain session data.
=head1 SYNOPSIS
- use Catalyst qw/Session Session::Store::FastMmap Session::State::Cookie/;
+ # To get sessions to "just work", all you need to do is use these plugins:
+
+ use Catalyst qw/
+ Session
+ Session::Store::FastMmap
+ Session::State::Cookie
+ /;
+
+ # you can replace Store::FastMmap with Store::File - both have sensible
+ # default configurations (see their docs for details)
+
+ # more complicated backends are available for other scenarios (DBI storage,
+ # etc)
+
+
+ # after you've loaded the plugins you can save session data
+ # For example, if you are writing a shopping cart, it could be implemented
+ # like this:
sub add_item : Local {
my ( $self, $c ) = @_;
my $item_id = $c->req->param("item");
- # $c->session is stored across requests, so
- # other actions will see these values
+ # $c->session is a hash ref, a bit like $c->stash
+ # the difference is that it' preserved across requests
push @{ $c->session->{items} }, $item_id;
# values in $c->session are restored
$c->stash->{items_to_display} =
- [ map { MyModel->retrieve($_) } @{ $c->session->{items} } ];
+ [ map { MyModel->retrieve($_) } @{ $c->session->{items} } ];
$c->forward("MyView");
}
This plugin links the two pieces together.
+=head1 RECOMENDED BACKENDS
+
+=over 4
+
+=item Session::State::Cookie
+
+The only really sane way to do state is using cookies.
+
+=item Session::Store::File
+
+A portable backend, based on Cache::File.
+
+=item Session::Store::FastMmap
+
+A fast and flexible backend, based on Cache::FastMmap.
+
+=back
+
=head1 METHODS
=over 4
This method will automatically create a new session and session ID if none
exists.
+=item session_expires
+
+=item session_expires $reset
+
+This method returns the time when the current session will expire, or 0 if
+there is no current session. If there is a session and it already expired, it
+will delete the session and return 0 as well.
+
+If the C<$reset> parameter is true, and there is a session ID the expiry time
+will be reset to the current time plus the time to live (see
+L</CONFIGURATION>). This is used when creating a new session.
+
+=item flash
+
+This is like Ruby on Rails' flash data structure. Think of it as a stash that
+lasts for longer than one request, letting you redirect instead of forward.
+
+The flash data will be cleaned up only on requests on which actually use
+$c->flash (thus allowing multiple redirections), and the policy is to delete
+all the keys which haven't changed since the flash data was loaded at the end
+of every request.
+
+ sub moose : Local {
+ my ( $self, $c ) = @_;
+
+ $c->flash->{beans} = 10;
+ $c->response->redirect( $c->uri_for("foo") );
+ }
+
+ sub foo : Local {
+ my ( $self, $c ) = @_;
+
+ my $value = $c->flash->{beans};
+
+ # ...
+
+ $c->response->redirect( $c->uri_for("bar") );
+ }
+
+ sub bar : Local {
+ my ( $self, $c ) = @_;
+
+ if ( exists $c->flash->{beans} ) { # false
+
+ }
+ }
+
+=item clear_flash
+
+Zap all the keys in the flash regardless of their current state.
+
+=item keep_flash @keys
+
+If you want to keep a flash key for the next request too, even if it hasn't
+changed, call C<keep_flash> and pass in the keys as arguments.
+
+=item delete_session REASON
+
+This method is used to invalidate a session. It takes an optional parameter
+which will be saved in C<session_delete_reason> if provided.
+
=item session_delete_reason
This accessor contains a string with the reason a session was deleted. Possible
=back
+=item session_expire_key $key, $ttl
+
+Mark a key to expire at a certain time (only useful when shorter than the
+expiry time for the whole session).
+
+For example:
+
+ __PACKAGE__->config->{session}{expires} = 1000000000000; # forever
+
+ # later
+
+ $c->session_expire_key( __user => 3600 );
+
+Will make the session data survive, but the user will still be logged out after
+an hour.
+
+Note that these values are not auto extended.
+
+=back
+
+=head1 INTERNAL METHODS
+
+=over 4
+
=item setup
This method is extended to also make calls to
=item prepare_action
-This methoid is extended, and will restore session data and check it for
-validity if a session id is defined. It assumes that the State plugin will
-populate the C<sessionid> key beforehand.
+This methoid is extended.
-=item finalize
+It's only effect is if the (off by default) C<flash_to_stash> configuration
+parameter is on - then it will copy the contents of the flash to the stash at
+prepare time.
-This method is extended and will extend the expiry time, as well as persist the
-session data if a session exists.
+=item finalize_headers
-=item delete_session REASON
+This method is extended and will extend the expiry time before sending
+the response.
-This method is used to invalidate a session. It takes an optional parameter
-which will be saved in C<session_delete_reason> if provided.
+=item finalize
+
+This method is extended and will call finalize_session after the other
+finalizes run. Here we persist the session data if a session exists.
=item initialize_session_data
This method will initialize the internal structure of the session, and is
called by the C<session> method if appropriate.
+=item create_session_id
+
+Creates a new session id using C<generate_session_id> if there is no session ID
+yet.
+
+=item validate_session_id SID
+
+Make sure a session ID is of the right format.
+
+This currently ensures that the session ID string is any amount of case
+insensitive hexadecimal characters.
+
=item generate_session_id
This method will return a string that can be used as a session ID. It is
=over 4
-=item *
+=item * A counter
-A counter
+=item * The current time
-=item *
+=item * One value from C<rand>.
-The current time
+=item * The stringified value of a newly allocated hash reference
-=item *
-
-One value from C<rand>.
-
-=item *
-
-The stringified value of a newly allocated hash reference
-
-=item *
-
-The stringified value of the Catalyst context object
+=item * The stringified value of the Catalyst context object
=back
Also have a look at L<Crypt::Random> and the various openssl bindings - these
modules provide APIs for cryptographically secure random data.
+=item finalize_session
+
+Clean up the session during C<finalize>.
+
+This clears the various accessors after saving to the store.
+
=item dump_these
See L<Catalyst/dump_these> - ammends the session data structure to the list of
dumped objects if session ID is defined.
+
+=item calculate_extended_session_expires
+
+=item calculate_initial_session_expires
+
+=item create_session_id_if_needed
+
+=item delete_session_id
+
+=item extend_session_expires
+
+=item extend_session_id
+
+=item get_session_id
+
+=item reset_session_expires
+
+=item session_is_valid
+
+=item set_session_id
+
=back
=head1 USING SESSIONS DURING PREPARE
C<prepare_action> L<Catalyst::Plugin::Session> will actually load the data from
the store.
- sub prepare_action {
- my $c = shift;
+ sub prepare_action {
+ my $c = shift;
- # don't touch $c->session yet!
-
- $c->NEXT::prepare_action( @_ );
+ # don't touch $c->session yet!
- $c->session; # this is OK
- $c->sessionid; # this is also OK
- }
+ $c->NEXT::prepare_action( @_ );
+
+ $c->session; # this is OK
+ $c->sessionid; # this is also OK
+ }
=head1 CONFIGURATION
=item verify_address
-When false, C<< $c->request->address >> will be checked at prepare time. If it
-is not the same as the address that initiated the session, the session is
-deleted.
+When true, C<<$c->request->address>> will be checked at prepare time. If it is
+not the same as the address that initiated the session, the session is deleted.
+
+Defaults to false.
+
+=item flash_to_stash
+
+This option makes it easier to have actions behave the same whether they were
+forwarded to or redirected to. On prepare time it copies the contents of
+C<flash> (if any) to the stash.
=back
=item __expires
-A timestamp whose value is the last second when the session is still valid. If
-a session is restored, and __expires is less than the current time, the session
-is deleted.
+This key no longer exists. Use C<session_expires> instead.
=item __updated
-The last time a session was saved. This is the value of
-C<< $c->{session}{__expires} - $c->config->{session}{expires} >>.
+The last time a session was saved to the store.
=item __created
=item __address
The value of C<< $c->request->address >> at the time the session was created.
-This value is only populated of C<verify_address> is true in the configuration.
+This value is only populated if C<verify_address> is true in the configuration.
=back
=head1 CAVEATS
+=head2 Round the Robin Proxies
+
C<verify_address> could make your site inaccessible to users who are behind
load balanced proxies. Some ISPs may give a different IP to each request by the
same client due to this type of proxying. If addresses are verified these
this box is checked it should delete the C<__address> sepcial key from the
session hash when the hash is first created.
+=head2 Race Conditions
+
+In this day and age where cleaning detergents and dutch football (not the
+american kind) teams roam the plains in great numbers, requests may happen
+simultaneously. This means that there is some risk of session data being
+overwritten, like this:
+
+=over 4
+
+=item 1.
+
+request a starts, request b starts, with the same session id
+
+=item 2.
+
+session data is loaded in request a
+
+=item 3.
+
+session data is loaded in request b
+
+=item 4.
+
+session data is changed in request a
+
+=item 5.
+
+request a finishes, session data is updated and written to store
+
+=item 6.
+
+request b finishes, session data is updated and written to store, overwriting
+changes by request a
+
+=back
+
+If this is a concern in your application, a soon to be developed locking
+solution is the only safe way to go. This will have a bigger overhead.
+
+For applications where any given user is only making one request at a time this
+plugin should be safe enough.
+
=head1 AUTHORS
Andy Grundman
+
Christian Hansen
-Yuval Kogman, C<nothingmuch@woobling.org>
+
+Yuval Kogman, C<nothingmuch@woobling.org> (current maintainer)
+
Sebastian Riedel
-=head1 COPYRIGHT & LICNESE
+And countless other contributers from #catalyst. Thanks guys!
+
+=head1 COPYRIGHT & LICENSE
- Copyright (c) 2005 the aforementioned authors. All rights
- reserved. This program is free software; you can redistribute
- it and/or modify it under the same terms as Perl itself.
+ Copyright (c) 2005 the aforementioned authors. All rights
+ reserved. This program is free software; you can redistribute
+ it and/or modify it under the same terms as Perl itself.
=cut