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