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NAME

POE::Component::SSLify::NonBlock - Nonblocking SSL for POE with client certificate verification.

SYNOPSIS

Server-side usage

   # Import the modules
   use POE::Component::SSLify qw( SSLify_Options SSLify_GetCTX );
   use POE::Component::SSLify::NonBlock qw( Server_SSLify_NonBlock );

   # Set the key + certificate file, only one time needed.
   eval { SSLify_Options( 'server.key', 'server.crt' ) };
   if ( $@ ) {
      # Unable to load key or certificate file...
   }

   # Create a normal SocketFactory wheel or something
   my $factory = POE::Wheel::SocketFactory->new( ... );

   # Converts the socket into a SSL socket POE can communicate with, every time on new socket needed.
   eval { $socket = Server_SSLify_NonBlock( SSLify_GetCTX(), $socket, { } ) };
   if ( $@ ) {
      # Unable to SSLify it...
   }

   # Now, hand it off to ReadWrite
   my $rw = POE::Wheel::ReadWrite->new(
      Handle   =>   $socket,
      ...
   );

ABSTRACT

Nonblocking SSL for POE with client certificate verification.

DESCRIPTION

This component represents a common way of using ssl on a server, which needs to ensure that no client can block the whole server. Further it allows to verificate client certificates.

Non-Blocking needed, especially on client certificate verification

SSL is a protocol which interacts with the client during the handshake multiple times. If the socket is blocking, as on pure POE::Component::SSLify, a client can block the whole server. Especially if you want to do client certificate verification, the user has the abilty to choose a client certificate. In this situation the ssl handshake is waiting, and in blocked mode the whole server also stops responding.

Client certificate verification

You have three opportunities to do client certificate verification:

  Easiest way: 
    Verify the certificate and let OpenSSL reject the connection during ssl handshake if there is no certificate or it is unstrusted.

  Advanced way:
    Verify the certificate and poe handler determines if there is no certificate or it is unstrusted.

  Complicated way:
    Verify the certificate and poe handler determines if there is no certificate, it is unstrusted or if it is blocked by a CRL.

Easiest way: Client certificat rejection in ssl handshake

Generally you can use the "Server-side usage" example above, but you have to enable the client certification feature with the "clientcertrequest" parameter. The Server_SSLify_NonBlock function allows a hash for parameters:

   use POE::Component::SSLify qw( SSLify_Options SSLify_GetCTX );
   use POE::Component::SSLify::NonBlock qw( Server_SSLify_NonBlock SSLify_Options_NonBlock_ClientCert Server_SSLify_NonBlock_ClientCertVerifyAgainstCRL Server_SSLify_NonBlock_ClientCertificateExists Server_SSLify_NonBlock_ClientCertIsValid Server_SSLify_NonBlock_SSLDone );
   use POE qw( Wheel::SocketFactory Driver::SysRW Filter::Stream Wheel::ReadWrite );

   eval { SSLify_Options( 'server.key', 'server.crt' ) };
   die "SSLify_Options: ".$@ if ( $@ );

   eval { SSLify_Options_NonBlock_ClientCert(SSLify_GetCTX(), 'ca.crt') };
   die "SSLify_Options_NonBlock_ClientCert: ".$@ if ( $@ );

   POE::Session->create(
      inline_states => {
         _start => sub {
            my ( $heap, $kernel ) = @_[ HEAP, KERNEL ];
            $heap->{server_wheel} = POE::Wheel::SocketFactory->new(
               BindAddress  => "0.0.0.0",
               BindPort     => 443,
               Reuse        => 'yes',
               SuccessEvent => 'client_accept',
               FailureEvent => 'accept_failure',
            );
         },
         client_accept => sub {
            my ( $heap, $kernel, $socket ) = @_[ HEAP, KERNEL, ARG0 ];
            eval { $socket = Server_SSLify_NonBlock( SSLify_GetCTX(), $socket, {
               clientcertrequest => 1,
               debug => 1
            } ) };
            if ( $@ ) {
               print "SSL Failed: ".$@."\n";
               delete $heap->{server}->{$wheel_id}->{wheel};
            }
            my $io_wheel = POE::Wheel::ReadWrite->new(
               Handle     => $socket,
               Driver     => POE::Driver::SysRW->new,
               Filter     => POE::Filter::Stream->new,
               InputEvent => 'client_input'
            );
            $heap->{server}->{$io_wheel->ID()}->{wheel} = $io_wheel;
            $heap->{server}->{$io_wheel->ID()}->{socket} = $socket;
         },
         client_input => sub {
            my ( $heap, $kernel, $input, $wheel_id ) = @_[ HEAP, KERNEL, ARG0, ARG1 ];
            $heap->{server}->{$wheel_id}->{wheel}->put("[".$wheel_id."] Yeah! You're authenticated!\n") if $canwrite;
            $kernel->yield("disconnect" => $wheel_id);
         },
         disconnect => sub {
            my ($heap, $kernel, $wheel_id) = @_[HEAP, KERNEL, ARG0];
            $kernel->delay(close_delayed => 1, $wheel_id)
               unless ($heap->{server}->{$wheel_id}->{disconnecting}++);
         },
         close_delayed => sub {
            my ($kernel, $heap, $wheel_id) = @_[KERNEL, HEAP, ARG0];
            delete $heap->{server}->{$wheel_id}->{wheel};
            delete $heap->{server}->{$wheel_id}->{socket};
         }
      }
   );
    
   $poe_kernel->run();

Now the server sends the request for a client certificate during SSL handshake. By default, POE::Component::SSLify::NonBlock aborts the connection if "clientcertrequest" is set and there is no client certificat or the certificate is not trusted.

Advanced way: Client certificat reject in POE Handler

   use POE::Component::SSLify qw( SSLify_Options SSLify_GetCTX );
   use POE::Component::SSLify::NonBlock qw( Server_SSLify_NonBlock SSLify_Options_NonBlock_ClientCert Server_SSLify_NonBlock_ClientCertVerifyAgainstCRL Server_SSLify_NonBlock_ClientCertificateExists Server_SSLify_NonBlock_ClientCertIsValid Server_SSLify_NonBlock_SSLDone );
   use POE qw( Wheel::SocketFactory Driver::SysRW Filter::Stream Wheel::ReadWrite );

   eval { SSLify_Options( 'server.key', 'server.crt' ) };
   die "SSLify_Options: ".$@ if ( $@ );

   eval { SSLify_Options_NonBlock_ClientCert(SSLify_GetCTX(), 'ca.crt') };
   die "SSLify_Options_NonBlock_ClientCert: ".$@ if ( $@ );

   POE::Session->create(
      inline_states => {
         _start => sub {
            my ( $heap, $kernel ) = @_[ HEAP, KERNEL ];
            $heap->{server_wheel} = POE::Wheel::SocketFactory->new(
               BindAddress  => "0.0.0.0",
               BindPort     => 443,
               Reuse        => 'yes',
               SuccessEvent => 'client_accept',
               FailureEvent => 'accept_failure',
            );
         },
         client_accept => sub {
            my ( $heap, $kernel, $socket ) = @_[ HEAP, KERNEL, ARG0 ];
            eval { $socket = Server_SSLify_NonBlock( SSLify_GetCTX(), $socket, {
               clientcertrequest => 1,
               noblockbadclientcert => 1,
               debug => 1
            } ) };
            if ( $@ ) {
               print "SSL Failed: ".$@."\n";
               delete $heap->{server}->{$wheel_id}->{wheel};
            }
            my $io_wheel = POE::Wheel::ReadWrite->new(
               Handle     => $socket,
               Driver     => POE::Driver::SysRW->new,
               Filter     => POE::Filter::Stream->new,
               InputEvent => 'client_input'
            );
            $heap->{server}->{$io_wheel->ID()}->{wheel} = $io_wheel;
            $heap->{server}->{$io_wheel->ID()}->{socket} = $socket;
         },
         client_input => sub {
            my ( $heap, $kernel, $input, $wheel_id ) = @_[ HEAP, KERNEL, ARG0, ARG1 ];
            my $canwrite = exists $heap->{server}->{$wheel_id}->{wheel} &&
                             (ref($heap->{server}->{$wheel_id}->{wheel}) eq "POE::Wheel::ReadWrite");
            my $socket = $heap->{server}->{$wheel_id}->{socket};
            return unless Server_SSLify_NonBlock_SSLDone($socket);
            if (!(Server_SSLify_NonBlock_ClientCertificateExists($socket))) {
               $heap->{server}->{$wheel_id}->{wheel}->put("[".$wheel_id."] NoClientCertExists\n") if $canwrite;
               return $kernel->yield("disconnect" => $wheel_id);
            } elsif(!(Server_SSLify_NonBlock_ClientCertIsValid($socket))) {
              $heap->{server}->{$wheel_id}->{wheel}->put("[".$wheel_id."] ClientCertInvalid\n") if $canwrite;
               return $kernel->yield("disconnect" => $wheel_id);
            }
            $heap->{server}->{$wheel_id}->{wheel}->put("[".$wheel_id."] Yeah! You're authenticated!\n") if $canwrite;
            $kernel->yield("disconnect" => $wheel_id);
         },
         disconnect => sub {
            my ($heap, $kernel, $wheel_id) = @_[HEAP, KERNEL, ARG0];
            $kernel->delay(close_delayed => 1, $wheel_id)
               unless ($heap->{server}->{$wheel_id}->{disconnecting}++);
         },
         close_delayed => sub {
            my ($kernel, $heap, $wheel_id) = @_[KERNEL, HEAP, ARG0];
            delete $heap->{server}->{$wheel_id}->{wheel};
            delete $heap->{server}->{$wheel_id}->{socket};
         }
      }
   );
    
   $poe_kernel->run();

Complicated way: Client certificate reject in POE Handler with CRL support

WARNING: To use this you have to patch the lines from net-ssleay-patch fike into Net::SSLeay (you find the patch in the base path of the tar.gz packet). Then recompile and reinstall the Net::SSLeay package.

   use POE::Component::SSLify qw( SSLify_Options SSLify_GetCTX );
   use POE::Component::SSLify::NonBlock qw( Server_SSLify_NonBlock SSLify_Options_NonBlock_ClientCert Server_SSLify_NonBlock_ClientCertVerifyAgainstCRL Server_SSLify_NonBlock_ClientCertificateExists Server_SSLify_NonBlock_ClientCertIsValid Server_SSLify_NonBlock_SSLDone );
   use POE qw( Wheel::SocketFactory Driver::SysRW Filter::Stream Wheel::ReadWrite );

   eval { SSLify_Options( 'server.key', 'server.crt' ) };
   die "SSLify_Options: ".$@ if ( $@ );

   eval { SSLify_Options_NonBlock_ClientCert(SSLify_GetCTX(), 'ca.crt') };
   die "SSLify_Options_NonBlock_ClientCert: ".$@ if ( $@ );

   POE::Session->create(
      inline_states => {
         _start => sub {
            my ( $heap, $kernel ) = @_[ HEAP, KERNEL ];
            $heap->{server_wheel} = POE::Wheel::SocketFactory->new(
               BindAddress  => "0.0.0.0",
               BindPort     => 443,
               Reuse        => 'yes',
               SuccessEvent => 'client_accept',
               FailureEvent => 'accept_failure',
            );
         },
         client_accept => sub {
            my ( $heap, $kernel, $socket ) = @_[ HEAP, KERNEL, ARG0 ];
            eval { $socket = Server_SSLify_NonBlock( SSLify_GetCTX(), $socket, {
               clientcertrequest => 1,
               noblockbadclientcert => 1,
               getserial => 1,
               debug => 1
            } ) };
            if ( $@ ) {
               print "SSL Failed: ".$@."\n";
               delete $heap->{server}->{$wheel_id}->{wheel};
            }
            my $io_wheel = POE::Wheel::ReadWrite->new(
               Handle     => $socket,
               Driver     => POE::Driver::SysRW->new,
               Filter     => POE::Filter::Stream->new,
               InputEvent => 'client_input'
            );
            $heap->{server}->{$io_wheel->ID()}->{wheel} = $io_wheel;
            $heap->{server}->{$io_wheel->ID()}->{socket} = $socket;
         },
         client_input => sub {
            my ( $heap, $kernel, $input, $wheel_id ) = @_[ HEAP, KERNEL, ARG0, ARG1 ];
            my $canwrite = exists $heap->{server}->{$wheel_id}->{wheel} &&
                             (ref($heap->{server}->{$wheel_id}->{wheel}) eq "POE::Wheel::ReadWrite");
            my $socket = $heap->{server}->{$wheel_id}->{socket};
            return unless Server_SSLify_NonBlock_SSLDone($socket);
            if (!(Server_SSLify_NonBlock_ClientCertificateExists($socket))) {
               $heap->{server}->{$wheel_id}->{wheel}->put("[".$wheel_id."] NoClientCertExists\n") if $canwrite;
               return $kernel->yield("disconnect" => $wheel_id);
            } elsif(!(Server_SSLify_NonBlock_ClientCertIsValid($socket))) {
              $heap->{server}->{$wheel_id}->{wheel}->put("[".$wheel_id."] ClientCertInvalid\n") if $canwrite;
               return $kernel->yield("disconnect" => $wheel_id);
            } elsif(!(Server_SSLify_NonBlock_ClientCertVerifyAgainstCRL($socket, 'ca.crl'))) {
               $heap->{server}->{$wheel_id}->{wheel}->put("[".$wheel_id."] CRL\n") if $canwrite;
               return $kernel->yield("disconnect" => $wheel_id);
            }
            $heap->{server}->{$wheel_id}->{wheel}->put("[".$wheel_id."] Yeah! You're authenticated!\n") if $canwrite;
            $kernel->yield("disconnect" => $wheel_id);
         },
         disconnect => sub {
            my ($heap, $kernel, $wheel_id) = @_[HEAP, KERNEL, ARG0];
            $kernel->delay(close_delayed => 1, $wheel_id)
               unless ($heap->{server}->{$wheel_id}->{disconnecting}++);
         },
         close_delayed => sub {
            my ($kernel, $heap, $wheel_id) = @_[KERNEL, HEAP, ARG0];
            delete $heap->{server}->{$wheel_id}->{wheel};
            delete $heap->{server}->{$wheel_id}->{socket};
         }
      }
   );
    
   $poe_kernel->run();

STARRTTLS

Starting version 0.40, you can do SSL after plain text. This is often called "STARTTLS", "AUTH TLS" or "AUTH SSL". Here an FTP example:

   use POE::Component::SSLify qw( SSLify_Options SSLify_GetCTX );
   use POE::Component::SSLify::NonBlock qw( Server_SSLify_NonBlock SSLify_Options_NonBlock_ClientCert Server_SSLify_NonBlock_ClientCertVerifyAgainstCRL Server_SSLify_NonBlock_ClientCertificateExists Server_SSLify_NonBlock_ClientCertIsValid Server_SSLify_NonBlock_SSLDone Server_SSLify_NonBlock_STARTTLS);
   use POE qw( Wheel::SocketFactory Driver::SysRW Filter::Stream Wheel::ReadWrite );

   eval { SSLify_Options( 'server.key', 'server.crt' ) };
   die "SSLify_Options: ".$@ if ( $@ );

   eval { SSLify_Options_NonBlock_ClientCert(SSLify_GetCTX(), 'ca.crt' ) };
   die "SSLify_Options_NonBlock_ClientCert: ".$@ if ( $@ );

   POE::Session->create(
      inline_states => {
         _start => sub {
            my ( $heap, $kernel ) = @_[ HEAP, KERNEL ];
            $heap->{server_wheel} = POE::Wheel::SocketFactory->new(
               BindAddress  => "0.0.0.0",
               BindPort     => 443,
               Reuse        => 'yes',
               SuccessEvent => 'client_accept',
               FailureEvent => 'accept_failure',
            );
         },
         client_accept => sub {
            my ( $heap, $kernel, $socket ) = @_[ HEAP, KERNEL, ARG0 ];
            eval { $socket = Server_SSLify_NonBlock( SSLify_GetCTX(), $socket, {
               debug => 1,
               starttls => 1
            } ) };
            if ( $@ ) {
               print "SSL Failed: ".$@."\n";
               delete $heap->{server}->{$wheel_id}->{wheel};
            }
            my $io_wheel = POE::Wheel::ReadWrite->new(
               Handle     => $socket,
               Driver     => POE::Driver::SysRW->new,
               Filter     => POE::Filter::Stream->new,
               InputEvent => 'client_input'
            );
            $heap->{server}->{$io_wheel->ID()}->{wheel} = $io_wheel;
            $heap->{server}->{$io_wheel->ID()}->{socket} = $socket;
            $io_wheel->put("220 ProFTPD\r\n");
         },
         client_input => sub {
            my ( $heap, $kernel, $input, $wheel_id ) = @_[ HEAP, KERNEL, ARG0, ARG1 ];
            my $canwrite = exists $heap->{server}->{$wheel_id}->{wheel} &&
                             (ref($heap->{server}->{$wheel_id}->{wheel}) eq "POE::Wheel::ReadWrite");
            my $socket = $heap->{server}->{$wheel_id}->{socket};
            if (($input =~ /TLS/i) ||
                ($input =~ /SSL/i)) {
               $heap->{server}->{$wheel_id}->{wheel}->put("220 starttls\r\n");
               $heap->{server}->{$wheel_id}->{wheel}->flush();
               Server_SSLify_NonBlock_STARTTLS($socket);
            }
            return unless Server_SSLify_NonBlock_SSLDone($socket);
            $heap->{server}->{$wheel_id}->{wheel}->put("220 Yeah! You're authenticated!\n") if ($canwrite && (!$heap->{server}->{$wheel_id}->{disconnecting}));
            $kernel->yield("disconnect" => $wheel_id);
         },
         disconnect => sub {
            my ($heap, $kernel, $wheel_id) = @_[HEAP, KERNEL, ARG0];
            $kernel->delay(close_delayed => 1, $wheel_id)
               unless ($heap->{server}->{$wheel_id}->{disconnecting}++);
         },
         close_delayed => sub {
            my ($kernel, $heap, $wheel_id) = @_[KERNEL, HEAP, ARG0];
            delete $heap->{server}->{$wheel_id}->{wheel};
            delete $heap->{server}->{$wheel_id}->{socket};
         }
      }
   );
    
   $poe_kernel->run();

FUNCTIONS

SSLify_Options_NonBlock_ClientCert($ctx, $cacrt)

Configures ssl ctx(context) to request from the client a certificate for authentication, which is verificated against the configured CA in the file $cacrt.

   SSLify_Options_NonBlock_ClientCert(SSLify_GetCTX(), 'ca.crt');

Note:

   SSLify_Options from POE::Component::SSLify must be called first!

Server_SSLify_NonBlock($ctx, $socket, %$options)

Similar to Server_SSLify from POE::Component::SSLify. It needs further the CTX of POE::Component::SSLify and a hash for special options:

   my $socket = shift;   # get the socket from somewhere
   $socket = Server_SSLify_NonBlock(SSLify_GetCTX(), $socket, { option1 => 1, option1 => 2,... });

Options are:

   clientcertrequest
      The client gets requested for a client certificat during 
      ssl handshake

   noblockbadclientcert
      If the client does not provide a client certificate or the
      client certificate is untrusted, the connection will not
      be aborted. You can check for the errors via the functions
      Server_SSLify_NonBlock_ClientCertificateExists and
      Server_SSLify_NonBlock_ClientCertIsValid.

   debug
      Get debug messages during ssl handshake. Especially usefull
      for Server_SSLify_NonBlock_ClientCertVerifyAgainstCRL.

   getserial
      Request the serial of the client certificate during
      ssl handshake.
      
      WARNING: You have to patch Net::SSLeay to provide the
               Net::SSLeay::X509_get_serialNumber function
               before you can set the getserial option! See the
               file net-ssleay-patch in the base path of the
               tar.gz of the packet.

   starttls
      Don't actually do SSL but later. It is initiated if you
      call Server_SSLify_NonBlock_STARTTLS.

Note:

   SSLify_Options from POE::Component::SSLify must be set first!

Server_SSLify_NonBlock_SSLDone

Checks if the SSL handshake has been completed.

   Server_SSLify_NonBlock_SSLDone($socket);

Server_SSLify_NonBlock_ClientCertificateExists($socket)

Verify if the client commited a valid client certificate.

  Server_SSLify_NonBlock_ClientCertificateExists($socket);

Server_SSLify_NonBlock_ClientCertIsValid($socket)

Verify if the client certificate is trusted by a loaded CA (see SSLify_Options_NonBlock_ClientCert).

  Server_SSLify_NonBlock_ClientCertIsValid($socket);

Server_SSLify_NonBlock_STARTTLS($socket)

Initiates SSL after plain text conversation. You have to use the starttls option in Server_SSLify_NonBlock.

  Server_SSLify_NonBlock_STARTTLS($socket)

See STARTTLS example above.

Server_SSLify_NonBlock_ClientCertVerifyAgainstCRL($socket, $crlfile)

Opens a CRL file, and verify if the serial of the client certificate is not contained in the CRL file. No file caching is done, each call opens the file again.

Note: If your CRL file is missing, can not be opened is empty, or has no blocked certificate at all, every call will get blocked.

  Server_SSLify_NonBlock_ClientCertVerifyAgainstCRL($socket, 'ca.crl');
  
   WARNING: You have to patch Net::SSLeay to provide the
            Net::SSLeay::verify_serial_against_crl_file function
            before you can set the getserial option! See the
            file net-ssleay-patch in the base path of the tar.gz
            of the packet.

Server_SSLify_NonBlock_GetClientCertificateIDs($socket)

Fetches the IDs as array of the clients certifcate and its signees.

Retruns empty list if you did not patch Net::SSLeay.

hexdump($string)

Returns string data in hex format.

For example:

  perl -e 'use POE::Component::SSLify::NonBlock; print POE::Component::SSLify::NonBlock::hexdump("test")."\n";'
  74:65:73:74

Futher functions...

You can use all functions from POE::Component::SSLify !

NOTES

Based on POE::Component::SSLify

This module is based on POE::Component::SSLify, so POE::Component::SSLify::NonBlock has the same issues.

EXPORT

Puts all of the above functions in @EXPORT_OK so you have to request them directly

BUGS

Server_SSLify_NonBlock_ClientCertVerifyAgainstCRL: certificate serials

Server_SSLify_NonBlock_ClientCertVerifyAgainstCRL also verifies against the serial of the CA! Make sure that you never use the serial of the CA for client certificates!

Win32

I did not test POE::Component::SSLify::NonBlock on Win32 platforms at all!

SEE ALSO

POE::Component::SSLify

Net::SSLeay

AUTHOR

pRiVi <pRiVi@cpan.org>

PROPS

This code is based on Apocalypse module POE::Component::SSLify, improved by client certification code and non-blocking sockets.

Copyright 2010 by Markus Mueller/Apocalypse/Rocco Caputo/Dariusz Jackowski.

COPYRIGHT AND LICENSE

Copyright 2010 by Markus Mueller

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.