C4/SIP/SIPServer.pm

   1 #!/usr/bin/perl
   2 package C4::SIP::SIPServer;
   3
   4 use strict;
   5 use warnings;
   6 use FindBin qw($Bin);
   7 use lib "$Bin";
   8 use Net::Server::PreFork;
   9 use IO::Socket::INET;
  10 use Socket qw(:DEFAULT :crlf);
  11 use Scalar::Util qw(blessed);
  12 require UNIVERSAL::require;
  13
  14 use C4::Context;
  15 use C4::SIP::Sip qw(syslog);
  16 use C4::SIP::Sip::Constants qw(:all);
  17 use C4::SIP::Sip::Configuration;
  18 use C4::SIP::Sip::Checksum qw(checksum verify_cksum);
  19 use C4::SIP::Sip::MsgType qw( handle login_core );
  20 use C4::SIP::Logger qw(set_logger);
  21
  22 use Koha::Caches;
  23
  24 use Koha::Logger;
  25 use C4::SIP::Trapper;
  26 tie *STDERR, "C4::SIP::Trapper";
  27
  28 use base qw(Net::Server::PreFork);
  29
  30 use constant LOG_SIP => "local6"; # Local alias for the logging facility
  31
  32 #
  33 # Main  # not really, since package SIPServer
  34 #
  35 # FIXME: Is this a module or a script?
  36 # A script with no MAIN namespace?
  37 # A module that takes command line args?
  38
  39 # Set interface to 'sip'
  40 C4::Context->interface('sip');
  41
  42 my %transports = (
  43     RAW    => \&raw_transport,
  44     telnet => \&telnet_transport,
  45 );
  46
  47 #
  48 # Read configuration
  49 #
  50 my $config = C4::SIP::Sip::Configuration->new( $ARGV[0] );
  51 my @parms;
  52
  53 #
  54 # Ports to bind
  55 #
  56 foreach my $svc (keys %{$config->{listeners}}) {
  57     push @parms, "port=" . $svc;
  58 }
  59
  60 #
  61 # Logging
  62 #
  63 # Log lines look like this:
  64 # Jun 16 21:21:31 server08 steve_sip[19305]: ILS::Transaction::Checkout performing checkout...
  65 # [  TIMESTAMP  ] [ HOST ] [ IDENT ]  PID  : Message...
  66 #
  67 # The IDENT is determined by config file 'server-params' arguments
  68
  69
  70 #
  71 # Server Management: set parameters for the Net::Server::PreFork
  72 # module.  The module silently ignores parameters that it doesn't
  73 # recognize, and complains about invalid values for parameters
  74 # that it does.
  75 #
  76 if (defined($config->{'server-params'})) {
  77     while (my ($key, $val) = each %{$config->{'server-params'}}) {
  78                 push @parms, $key . '=' . $val;
  79     }
  80 }
  81
  82
  83 #
  84 # This is the main event.
  85 __PACKAGE__ ->run(@parms);
  86
  87 #
  88 # Child
  89 #
  90
  91 # process_request is the callback used by Net::Server to handle
  92 # an incoming connection request.
  93
  94 sub process_request {
  95     my $self = shift;
  96     my $service;
  97     my ($sockaddr, $port, $proto);
  98     my $transport;
  99
 100     $self->{config} = $config;
 101
 102     # Flushing L1 to make sure the request will be processed using the correct data
 103     Koha::Caches->flush_L1_caches();
 104
 105     $self->{account} = undef;  # Clear out the account from the last request, it may be different
 106     $self->{logger} = set_logger( Koha::Logger->get( { interface => 'sip' } ) );
 107
 108     # Flush previous MDCs to prevent accidentally leaking incorrect MDC-entries
 109     Log::Log4perl::MDC->put( "accountid", undef );
 110     Log::Log4perl::MDC->put( "peeraddr",  undef );
 111
 112     my $sockname = getsockname(STDIN);
 113
 114     # Check if socket connection is IPv6 before resolving address
 115     my $family = Socket::sockaddr_family($sockname);
 116     if ($family == AF_INET6) {
 117       ($port, $sockaddr) = sockaddr_in6($sockname);
 118       $sockaddr = Socket::inet_ntop(AF_INET6, $sockaddr);
 119     } else {
 120       ($port, $sockaddr) = sockaddr_in($sockname);
 121       $sockaddr = inet_ntoa($sockaddr);
 122     }
 123     $proto = $self->{server}->{client}->NS_proto();
 124
 125     $self->{service} = $config->find_service($sockaddr, $port, $proto);
 126
 127     if (!defined($self->{service})) {
 128                 syslog("LOG_ERR", "process_request: Unknown recognized server connection: %s:%s/%s", $sockaddr, $port, $proto);
 129                 die "process_request: Bad server connection";
 130     }
 131
 132     $transport = $transports{$self->{service}->{transport}};
 133
 134     if (!defined($transport)) {
 135                 syslog("LOG_WARNING", "Unknown transport '%s', dropping", $service->{transport});
 136                 return;
 137     } else {
 138                 &$transport($self);
 139     }
 140     return;
 141 }
 142
 143 #
 144 # Transports
 145 #
 146
 147 sub raw_transport {
 148     my $self = shift;
 149     my $input;
 150     my $service = $self->{service};
 151     # If using Net::Server::PreFork you may already have account set from a previous session
 152     # Ensure you dont
 153     if ($self->{account}) {
 154         delete $self->{account};
 155     }
 156
 157     # Timeout the while loop if we get stuck in it
 158     # In practice it should only iterate once but be prepared
 159     local $SIG{ALRM} = sub { die 'raw transport Timed Out!' };
 160     my $timeout = $self->get_timeout({ transport => 1 });
 161     syslog('LOG_DEBUG', "raw_transport: timeout is $timeout");
 162     alarm $timeout;
 163     while (!$self->{account}) {
 164         $input = read_request();
 165         if (!$input) {
 166             # EOF on the socket
 167             syslog("LOG_INFO", "raw_transport: shutting down: EOF during login");
 168             return;
 169         }
 170         $input =~ s/[\r\n]+$//sm; # Strip off trailing line terminator(s)
 171         my $reg = qr/^${\(LOGIN)}/;
 172         last if $input !~ $reg ||
 173             C4::SIP::Sip::MsgType::handle($input, $self, LOGIN);
 174     }
 175     alarm 0;
 176
 177     $self->{logger} = set_logger(
 178         Koha::Logger->get(
 179             {
 180                 interface => 'sip',
 181                 category  => $self->{account}->{id}, # Add id to namespace
 182             }
 183         )
 184     );
 185
 186     # Set MDCs after properly authenticating
 187     Log::Log4perl::MDC->put( "accountid", $self->{account}->{id} );
 188     Log::Log4perl::MDC->put( "peeraddr",  $self->{server}->{peeraddr} );
 189
 190     syslog("LOG_DEBUG", "raw_transport: uname/inst: '%s/%s'",
 191         $self->{account}->{id},
 192         $self->{account}->{institution});
 193     if (! $self->{account}->{id}) {
 194         syslog("LOG_ERR","Login failed shutting down");
 195         return;
 196     }
 197
 198     $self->sip_protocol_loop();
 199     syslog("LOG_INFO", "raw_transport: shutting down");
 200     return;
 201 }
 202
 203 sub get_clean_string {
 204         my $string = shift;
 205         if (defined $string) {
 206                 syslog("LOG_DEBUG", "get_clean_string  pre-clean(length %s): %s", length($string), $string);
 207                 chomp($string);
 208                 $string =~ s/^[^A-z0-9]+//;
 209                 $string =~ s/[^A-z0-9]+$//;
 210                 syslog("LOG_DEBUG", "get_clean_string post-clean(length %s): %s", length($string), $string);
 211         } else {
 212                 syslog("LOG_INFO", "get_clean_string called on undefined");
 213         }
 214         return $string;
 215 }
 216
 217 sub get_clean_input {
 218         local $/ = "\012";
 219         my $in = <STDIN>;
 220         $in = get_clean_string($in);
 221         while (my $extra = <STDIN>){
 222                 syslog("LOG_ERR", "get_clean_input got extra lines: %s", $extra);
 223         }
 224         return $in;
 225 }
 226
 227 sub telnet_transport {
 228     my $self = shift;
 229     my ($uid, $pwd);
 230     my $strikes = 3;
 231     my $account = undef;
 232     my $input;
 233     my $config  = $self->{config};
 234     my $timeout = $self->get_timeout({ transport => 1 });
 235     syslog("LOG_DEBUG", "telnet_transport: timeout is $timeout");
 236
 237     eval {
 238         local $SIG{ALRM} = sub { die "telnet_transport: Timed Out ($timeout seconds)!\n"; };
 239         local $| = 1;                   # Unbuffered output
 240         $/ = "\015";            # Internet Record Separator (lax version)
 241     # Until the terminal has logged in, we don't trust it
 242     # so use a timeout to protect ourselves from hanging.
 243
 244         while ($strikes--) {
 245             print "login: ";
 246                 alarm $timeout;
 247                 # $uid = &get_clean_input;
 248                 $uid = <STDIN>;
 249             print "password: ";
 250             # $pwd = &get_clean_input || '';
 251                 $pwd = <STDIN>;
 252                 alarm 0;
 253
 254                 syslog("LOG_DEBUG", "telnet_transport 1: uid length %s, pwd length %s", length($uid), length($pwd));
 255                 $uid = get_clean_string ($uid);
 256                 $pwd = get_clean_string ($pwd);
 257                 syslog("LOG_DEBUG", "telnet_transport 2: uid length %s, pwd length %s", length($uid), length($pwd));
 258
 259             if (exists ($config->{accounts}->{$uid})
 260                 && ($pwd eq $config->{accounts}->{$uid}->{password})) {
 261                         $account = $config->{accounts}->{$uid};
 262                         if ( C4::SIP::Sip::MsgType::login_core($self,$uid,$pwd) ) {
 263                 last;
 264             }
 265             }
 266                 syslog("LOG_WARNING", "Invalid login attempt: '%s'", ($uid||''));
 267                 print("Invalid login$CRLF");
 268         }
 269     }; # End of eval
 270
 271     if ($@) {
 272                 syslog("LOG_ERR", "telnet_transport: Login timed out");
 273                 die "Telnet Login Timed out";
 274     } elsif (!defined($account)) {
 275                 syslog("LOG_ERR", "telnet_transport: Login Failed");
 276                 die "Login Failure";
 277     } else {
 278                 print "Login OK.  Initiating SIP$CRLF";
 279     }
 280
 281     $self->{account} = $account;
 282     syslog("LOG_DEBUG", "telnet_transport: uname/inst: '%s/%s'", $account->{id}, $account->{institution});
 283     $self->sip_protocol_loop();
 284     syslog("LOG_INFO", "telnet_transport: shutting down");
 285     return;
 286 }
 287
 288 #
 289 # The terminal has logged in, using either the SIP login process
 290 # over a raw socket, or via the pseudo-unix login provided by the
 291 # telnet transport.  From that point on, both the raw and the telnet
 292 # processes are the same:
 293 sub sip_protocol_loop {
 294     my $self = shift;
 295     my $service = $self->{service};
 296     my $config  = $self->{config};
 297     my $timeout = $self->get_timeout({ client => 1 });
 298
 299     # The spec says the first message will be:
 300     #     SIP v1: SC_STATUS
 301     #     SIP v2: LOGIN (or SC_STATUS via telnet?)
 302     # But it might be SC_REQUEST_RESEND.  As long as we get
 303     # SC_REQUEST_RESEND, we keep waiting.
 304
 305     # Comprise reports that no other ILS actually enforces this
 306     # constraint, so we'll relax about it too.
 307     # Using the SIP "raw" login process, rather than telnet,
 308     # requires the LOGIN message and forces SIP 2.00.  In that
 309     # case, the LOGIN message has already been processed (above).
 310
 311     # In short, we'll take any valid message here.
 312     eval {
 313         local $SIG{ALRM} = sub {
 314             syslog( 'LOG_DEBUG', 'Inactive: timed out' );
 315             die "Timed Out!\n";
 316         };
 317         my $previous_alarm = alarm($timeout);
 318
 319         while ( my $inputbuf = read_request() ) {
 320             if ( !defined $inputbuf ) {
 321                 return;    #EOF
 322             }
 323             alarm($timeout);
 324
 325             unless ($inputbuf) {
 326                 syslog( "LOG_ERR", "sip_protocol_loop: empty input skipped" );
 327                 print("96$CR");
 328                 next;
 329             }
 330
 331             my $status = C4::SIP::Sip::MsgType::handle( $inputbuf, $self, q{} );
 332             if ( !$status ) {
 333                 syslog(
 334                     "LOG_ERR",
 335                     "sip_protocol_loop: failed to handle %s",
 336                     substr( $inputbuf, 0, 2 )
 337                 );
 338             }
 339             next if $status eq REQUEST_ACS_RESEND;
 340         }
 341         alarm($previous_alarm);
 342         return;
 343     };
 344     if ( $@ =~ m/timed out/i ) {
 345         return;
 346     }
 347     return;
 348 }
 349
 350 sub read_request {
 351       my $raw_length;
 352       local $/ = "\015";
 353
 354     # proper SPEC: (octal) \015 = (hex) x0D = (dec) 13 = (ascii) carriage return
 355       my $buffer = <STDIN>;
 356       if ( defined $buffer ) {
 357           STDIN->flush();    # clear an extra linefeed
 358           chomp $buffer;
 359           $raw_length = length $buffer;
 360           $buffer =~ s/^\s*[^A-z0-9]+//s;
 361 # Every line must start with a "real" character.  Not whitespace, control chars, etc.
 362           $buffer =~ s/[^A-z0-9]+$//s;
 363
 364 # Same for the end.  Note this catches the problem some clients have sending empty fields at the end, like |||
 365           $buffer =~ s/\015?\012//g;    # Extra line breaks must die
 366           $buffer =~ s/\015?\012//s;    # Extra line breaks must die
 367           $buffer =~ s/\015*\012*$//s;
 368
 369     # treat as one line to include the extra linebreaks we are trying to remove!
 370       }
 371       else {
 372           syslog( 'LOG_DEBUG', 'EOF returned on read' );
 373           return;
 374       }
 375       my $len = length $buffer;
 376       if ( $len != $raw_length ) {
 377           my $trim = $raw_length - $len;
 378           syslog( 'LOG_DEBUG', "read_request trimmed $trim character(s) " );
 379       }
 380
 381       syslog( 'LOG_INFO', "INPUT MSG: '$buffer'" );
 382       return $buffer;
 383 }
 384
 385 # $server->get_timeout({ $type => 1, fallback => $fallback });
 386 #     where $type is transport | client | policy
 387 #
 388 # Centralizes all timeout logic.
 389 # Transport refers to login process, client to active connections.
 390 # Policy timeout is transaction timeout (used in ACS status message).
 391 #
 392 # Fallback is optional. If you do not pass transport, client or policy,
 393 # you will get fallback or hardcoded default.
 394
 395 sub get_timeout {
 396     my ( $server, $params ) = @_;
 397     my $fallback = $params->{fallback} || 30;
 398     my $service = $server->{service} // {};
 399     my $config = $server->{config} // {};
 400
 401     if( $params->{transport} ||
 402         ( $params->{client} && !exists $service->{client_timeout} )) {
 403         # We do not allow zero values here.
 404         # Note: config/timeout seems to be deprecated.
 405         return $service->{timeout} || $config->{timeout} || $fallback;
 406
 407     } elsif( $params->{client} ) {
 408         # We know that client_timeout exists now.
 409         # We do allow zero values here to indicate no timeout.
 410         return 0 if $service->{client_timeout} =~ /^0+$|\D/;
 411         return $service->{client_timeout};
 412
 413     } elsif( $params->{policy} ) {
 414         my $policy = $server->{policy} // {};
 415         my $rv = sprintf( "%03d", $policy->{timeout} // 0 );
 416         if( length($rv) != 3 ) {
 417             syslog( "LOG_ERR", "Policy timeout has wrong size: '%s'", $rv );
 418             return '000';
 419         }
 420         return $rv;
 421
 422     } else {
 423         return $fallback;
 424     }
 425 }
 426
 427 1;
 428
 429 __END__