X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FCatalyst%2FPlugin%2FSession.pm;h=732b56c57a07f440e417bce920f4318ba15a0442;hb=ec299c02b224a28ab5fcec81c908f82563445382;hp=e5b3934508087bb7af65c72028c917edaacb1446;hpb=0974ac0669aaf4c828c42786e877e5a20880f1f7;p=catagits%2FCatalyst-Plugin-Session.git diff --git a/lib/Catalyst/Plugin/Session.pm b/lib/Catalyst/Plugin/Session.pm index e5b3934..732b56c 100644 --- a/lib/Catalyst/Plugin/Session.pm +++ b/lib/Catalyst/Plugin/Session.pm @@ -10,11 +10,28 @@ use NEXT; use Catalyst::Exception (); use Digest (); use overload (); +use Object::Signature (); -our $VERSION = "0.02"; +our $VERSION = "0.09"; +my @session_data_accessors; # used in delete_session BEGIN { - __PACKAGE__->mk_accessors(qw/_sessionid _session session_delete_reason/); + __PACKAGE__->mk_accessors( + "_session_delete_reason", + @session_data_accessors = qw/ + _sessionid + _session + _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 { @@ -57,98 +74,310 @@ sub setup_session { $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 { my $c = shift; + $c->_save_session_expires; + $c->_save_session; + $c->_save_flash; + $c->_save_session_id; + + $c->NEXT::finalize(@_); +} + +sub _save_session_id { + my $c = shift; +} + +sub _save_session_expires { + my $c = shift; + + if ( defined(my $expires = $c->_session_expires) ) { + my $sid = $c->sessionid; + $c->store_session_data( "expires:$sid" => $expires ); + + $c->_session_expires(undef); + $c->_tried_loading_session_expires(undef); + } +} + +sub _save_session { + my $c = shift; + if ( my $session_data = $c->_session ) { - # all sessions are extended at the end of the request - my $now = time; - @{ $session_data }{qw/__updated __expires/} = - ( $now, $c->config->{session}{expires} + $now ); - $c->store_session_data( $c->sessionid, $session_data ); + no warnings 'uninitialized'; + if ( Object::Signature::signature($session_data) ne + $c->_session_data_sig ) + { + $session_data->{__updated} = time(); + my $sid = $c->sessionid; + $c->store_session_data( "session:$sid" => $session_data ); + } + + $c->_session(undef); + $c->_tried_loading_session_data(undef); } +} - $c->NEXT::finalize(@_); +sub _save_flash { + my $c = shift; + + if ( my $flash_data = $c->_flash ) { + + 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}; + } + } + + my $sid = $c->sessionid; + + if (%$flash_data) { + $c->store_session_data( "flash:$sid", $flash_data ); + } + else { + $c->delete_session_data("flash:$sid"); + } + + $c->_flash(undef); + $c->_tried_loading_flash_data(undef); + } } -sub prepare_action { +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 ) { - no warnings 'uninitialized'; # ne __address + my $expires = $c->get_session_data("expires:$sid") || 0; - my $session_data = $c->_session || $c->_session( $c->get_session_data($sid) ); - if ( !$session_data or $session_data->{__expires} < time ) { + if ( $expires >= time() ) { + return $c->extend_session_expires( $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->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; + } - # session expired - $c->log->debug("Deleting session $sid (expired)") if $c->debug; - $c->delete_session("session expired"); + $c->log->debug(qq/Restored session "$sid"/) if $c->debug; + $c->_session_data_sig( Object::Signature::signature($session_data) ) if $session_data; + $c->_expire_session_keys; + + return $session_data; } - elsif ($c->config->{session}{verify_address} - && $session_data->{__address} ne $c->request->address ) + } + + 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->log->warn( - "Deleting session $sid due to address mismatch (" - . $session_data->{__address} . " != " - . $c->request->address . ")", - ); - $c->delete_session("address mismatch"); - } - else { - $c->log->debug(qq/Restored session "$sid"/) if $c->debug; + $c->_flash_key_hashes({ map { $_ => Object::Signature::signature( \$flash_data->{$_} ) } keys %$flash_data }); + + return $flash_data; } } - $c->NEXT::prepare_action(@_); + 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 delete_session { my ( $c, $msg ) = @_; + $c->log->debug("Deleting session") 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 + $c->$_(undef) for @session_data_accessors; + + $c->_session_delete_reason($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->_session_expires ) ) { + return $expires; + } elsif ( defined( $expires = $c->_load_session_expires ) ) { + $c->_session_expires($expires); + return $expires; + } else { + return 0; + } +} + +sub extend_session_expires { + my ( $c, $expires ) = @_; + $c->_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 ) = @_; + $c->_session_expires( my $exp = $c->calculate_initial_session_expires ); + $exp; } sub sessionid { - my $c = shift; - - if ( @_ ) { - if ( $c->validate_session_id( my $sid = shift ) ) { - return $c->_sessionid( $sid ); - } else { - my $err = "Tried to set invalid session ID '$sid'"; - $c->log->error( $err ); - Catalyst::Exception->throw( $err ); - } - } + my $c = shift; + + return $c->_sessionid || $c->_load_sessionid; +} - return $c->_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 ) = @_; + my ( $c, $sid ) = @_; - $sid =~ /^[a-f\d]+$/i; + $sid and $sid =~ /^[a-f\d]+$/i; } sub session { my $c = shift; - $c->_session || do { - my $sid = $c->generate_session_id; - $c->sessionid($sid); + $c->_session || $c->_load_session || do { + $c->create_session_id_if_needed; + $c->initialize_session_data; + }; +} + +sub keep_flash { + my ( $c, @keys ) = @_; + my $href = $c->_flash_keep_keys || $c->_flash_keep_keys({}); + (@{$href}{@keys}) = ((undef) x @keys); +} + +sub flash { + my $c = shift; + $c->_flash || $c->_load_flash || do { + $c->create_session_id_if_needed; + $c->_flash( {} ); + } +} - $c->log->debug(qq/Created session "$sid"/) if $c->debug; +sub session_expire_key { + my ( $c, %keys ) = @_; - $c->initialize_session_data; - }; + my $now = time; + @{ $c->session->{__expire_keys} }{ keys %keys } = + map { $now + $_ } values %keys; } sub initialize_session_data { @@ -156,17 +385,18 @@ sub initialize_session_data { my $now = time; - return $c->_session({ - __created => $now, - __updated => $now, - __expires => $now + $c->config->{session}{expires}, - - ( - $c->config->{session}{verify_address} - ? ( __address => $c->request->address ) - : () - ), - }); + return $c->_session( + { + __created => $now, + __updated => $now, + + ( + $c->config->{session}{verify_address} + ? ( __address => $c->request->address ) + : () + ), + } + ); } sub generate_session_id { @@ -177,6 +407,25 @@ 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 { @@ -189,17 +438,16 @@ my $usable; sub _find_digest () { unless ($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); @@ -217,6 +465,12 @@ sub dump_these { ); } + +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__ @@ -322,6 +576,63 @@ requests. 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). 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 keep_flash @keys + +If you wawnt to keep a flash key for the next request too, even if it hasn't +changed, call C 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 if provided. + =item session_delete_reason This accessor contains a string with the reason a session was deleted. Possible @@ -339,9 +650,27 @@ C =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 + + $c->session_expire_key( __user => 3600 ); + +Will make the session data survive, but the user will still be logged out after +an hour. + +Note that these values are not auto extended. + =back -=item INTERNAL METHODS +=head1 INTERNAL METHODS =over 4 @@ -362,25 +691,34 @@ listed in L. =item prepare_action -This methoid is extended, and will restore session data and check it for -validity if a session id is defined. It assumes that the State plugin will -populate the C key beforehand. +This methoid is extended. + +It's only effect is if the (off by default) C configuration +parameter is on - then it will copy the contents of the flash to the stash at +prepare time. =item finalize This method is extended and will extend the expiry time, as well as persist the session data if a session exists. -=item delete_session REASON - -This method is used to invalidate a session. It takes an optional parameter -which will be saved in C if provided. - =item initialize_session_data This method will initialize the internal structure of the session, and is called by the C method if appropriate. +=item create_session_id + +Creates a new session id using C if there is no session ID +yet. + +=item validate_session_id SID + +Make sure a session ID is of the right format. + +This currently ensures that the session ID string is any amount of case +insensitive hexadecimal characters. + =item generate_session_id This method will return a string that can be used as a session ID. It is @@ -395,13 +733,6 @@ overridable in case you want to provide more random data. Currently it returns a concatenated string which contains: -=item validate_session_id SID - -Make sure a session ID is of the right format. - -This currently ensures that the session ID string is any amount of case -insensitive hexadecimal characters. - =over 4 =item * @@ -496,6 +827,12 @@ hours). When true, C<<$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. +=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 (if any) to the stash. + =back =head1 SPECIAL KEYS @@ -507,14 +844,11 @@ are automatically set: =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 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 @@ -529,6 +863,8 @@ This value is only populated if C is true in the configuration. =head1 CAVEATS +=head2 Round the Robin Proxies + C 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 @@ -540,12 +876,63 @@ that it's OK for the address of the client to change. When the server sees that 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 -Sebastian Riedel +=over 4 + +=item Andy Grundman + +=item Christian Hansen + +=item Yuval Kogman, C (current maintainer) + +=item Sebastian Riedel + +=back + +And countless other contributers from #catalyst. Thanks guys! =head1 COPYRIGHT & LICENSE