C4/SIP/SIPServer.pm

   1 package SIPServer;
   2
   3 use strict;
   4 use warnings;
   5 # use Exporter;
   6 use Sys::Syslog qw(syslog);
   7 use Net::Server::PreFork;
   8 use IO::Socket::INET;
   9 use Socket qw(:DEFAULT :crlf);
  10 use Data::Dumper;               # For debugging
  11 require UNIVERSAL::require;
  12
  13 #use Sip qw(readline);
  14 use Sip::Constants qw(:all);
  15 use Sip::Configuration;
  16 use Sip::Checksum qw(checksum verify_cksum);
  17 use Sip::MsgType;
  18
  19 use constant LOG_SIP => "local6"; # Local alias for the logging facility
  20
  21 use vars qw(@ISA $VERSION);
  22
  23 BEGIN {
  24         $VERSION = 1.02;
  25         @ISA = qw(Net::Server::PreFork);
  26 }
  27
  28 #
  29 # Main  # not really, since package SIPServer
  30 #
  31 # FIXME: Is this a module or a script?
  32 # A script with no MAIN namespace?
  33 # A module that takes command line args?
  34
  35 my %transports = (
  36     RAW    => \&raw_transport,
  37     telnet => \&telnet_transport,
  38     # http   => \&http_transport,       # for http just use the OPAC
  39 );
  40
  41 #
  42 # Read configuration
  43 #
  44 my $config = new Sip::Configuration $ARGV[0];
  45 print STDERR "SIPServer config: \n" . Dumper($config) . "\nEND SIPServer config.\n";
  46 my @parms;
  47
  48 #
  49 # Ports to bind
  50 #
  51 foreach my $svc (keys %{$config->{listeners}}) {
  52     push @parms, "port=" . $svc;
  53 }
  54
  55 #
  56 # Logging
  57 #
  58 # Log lines look like this:
  59 # Jun 16 21:21:31 server08 steve_sip[19305]: ILS::Transaction::Checkout performing checkout...
  60 # [  TIMESTAMP  ] [ HOST ] [ IDENT ]  PID  : Message...
  61 #
  62 # The IDENT is determined by config file 'server-params' arguments
  63
  64
  65 #
  66 # Server Management: set parameters for the Net::Server::PreFork
  67 # module.  The module silently ignores parameters that it doesn't
  68 # recognize, and complains about invalid values for parameters
  69 # that it does.
  70 #
  71 if (defined($config->{'server-params'})) {
  72     while (my ($key, $val) = each %{$config->{'server-params'}}) {
  73                 push @parms, $key . '=' . $val;
  74     }
  75 }
  76
  77 print scalar(localtime),  " -- startup -- procid:$$\n";
  78 print "Params for Net::Server::PreFork : \n" . Dumper(\@parms);
  79
  80 #
  81 # This is the main event.
  82 __PACKAGE__ ->run(@parms);
  83
  84 #
  85 # Child
  86 #
  87
  88 # process_request is the callback used by Net::Server to handle
  89 # an incoming connection request.
  90
  91 sub process_request {
  92     my $self = shift;
  93     my $service;
  94     my ($sockaddr, $port, $proto);
  95     my $transport;
  96
  97     $self->{config} = $config;
  98
  99     my $sockname = getsockname(STDIN);
 100     ($port, $sockaddr) = sockaddr_in($sockname);
 101     $sockaddr = inet_ntoa($sockaddr);
 102     $proto = $self->{server}->{client}->NS_proto();
 103
 104     $self->{service} = $config->find_service($sockaddr, $port, $proto);
 105
 106     if (!defined($self->{service})) {
 107                 syslog("LOG_ERR", "process_request: Unknown recognized server connection: %s:%s/%s", $sockaddr, $port, $proto);
 108                 die "process_request: Bad server connection";
 109     }
 110
 111     $transport = $transports{$self->{service}->{transport}};
 112
 113     if (!defined($transport)) {
 114                 syslog("LOG_WARNING", "Unknown transport '%s', dropping", $service->{transport});
 115                 return;
 116     } else {
 117                 &$transport($self);
 118     }
 119 }
 120
 121 #
 122 # Transports
 123 #
 124
 125 sub raw_transport {
 126     my $self = shift;
 127     my ($input);
 128     my $service = $self->{service};
 129     my $strikes = 3;
 130
 131     eval {
 132                 local $SIG{ALRM} = sub { die "raw_transport Timed Out!\n"; };
 133                 syslog("LOG_DEBUG", "raw_transport: timeout is %d", $service->{timeout});
 134                 while ($strikes--) {
 135                     alarm $service->{timeout};
 136                     $input = Sip::read_SIP_packet(*STDIN);
 137                     alarm 0;
 138                         if (!$input) {
 139                                 # EOF on the socket
 140                                 syslog("LOG_INFO", "raw_transport: shutting down: EOF during login");
 141                                 return;
 142                     }
 143                     $input =~ s/[\r\n]+$//sm;   # Strip off trailing line terminator(s)
 144                     last if Sip::MsgType::handle($input, $self, LOGIN);
 145                 }
 146         };
 147
 148     if (length $@) {
 149                 syslog("LOG_ERR", "raw_transport: LOGIN ERROR: '$@'");
 150                 die "raw_transport: login error (timeout? $@), exiting";
 151     } elsif (!$self->{account}) {
 152                 syslog("LOG_ERR", "raw_transport: LOGIN FAILED");
 153                 die "raw_transport: Login failed (no account), exiting";
 154     }
 155
 156     syslog("LOG_DEBUG", "raw_transport: uname/inst: '%s/%s'",
 157            $self->{account}->{id},
 158            $self->{account}->{institution});
 159
 160     $self->sip_protocol_loop();
 161     syslog("LOG_INFO", "raw_transport: shutting down");
 162 }
 163
 164 sub get_clean_string ($) {
 165         my $string = shift;
 166         if (defined $string) {
 167                 syslog("LOG_DEBUG", "get_clean_string  pre-clean(length %s): %s", length($string), $string);
 168                 chomp($string);
 169                 $string =~ s/^[^A-z0-9]+//;
 170                 $string =~ s/[^A-z0-9]+$//;
 171                 syslog("LOG_DEBUG", "get_clean_string post-clean(length %s): %s", length($string), $string);
 172         } else {
 173                 syslog("LOG_INFO", "get_clean_string called on undefined");
 174         }
 175         return $string;
 176 }
 177
 178 sub get_clean_input {
 179         local $/ = "\012";
 180         my $in = <STDIN>;
 181         $in = get_clean_string($in);
 182         while (my $extra = <STDIN>){
 183                 syslog("LOG_ERR", "get_clean_input got extra lines: %s", $extra);
 184         }
 185         return $in;
 186 }
 187
 188 sub telnet_transport {
 189     my $self = shift;
 190     my ($uid, $pwd);
 191     my $strikes = 3;
 192     my $account = undef;
 193     my $input;
 194     my $config  = $self->{config};
 195         my $timeout = $self->{service}->{timeout} || $config->{timeout} || 30;
 196         syslog("LOG_DEBUG", "telnet_transport: timeout is %s", $timeout);
 197
 198     eval {
 199         local $SIG{ALRM} = sub { die "telnet_transport: Timed Out ($timeout seconds)!\n"; };
 200         local $| = 1;                   # Unbuffered output
 201         $/ = "\015";            # Internet Record Separator (lax version)
 202     # Until the terminal has logged in, we don't trust it
 203     # so use a timeout to protect ourselves from hanging.
 204
 205         while ($strikes--) {
 206             print "login: ";
 207                 alarm $timeout;
 208                 # $uid = &get_clean_input;
 209                 $uid = <STDIN>;
 210             print "password: ";
 211             # $pwd = &get_clean_input || '';
 212                 $pwd = <STDIN>;
 213                 alarm 0;
 214
 215                 syslog("LOG_DEBUG", "telnet_transport 1: uid length %s, pwd length %s", length($uid), length($pwd));
 216                 $uid = get_clean_string ($uid);
 217                 $pwd = get_clean_string ($pwd);
 218                 syslog("LOG_DEBUG", "telnet_transport 2: uid length %s, pwd length %s", length($uid), length($pwd));
 219
 220             if (exists ($config->{accounts}->{$uid})
 221                 && ($pwd eq $config->{accounts}->{$uid}->password())) {
 222                         $account = $config->{accounts}->{$uid};
 223                         Sip::MsgType::login_core($self,$uid,$pwd) and last;
 224             }
 225                 syslog("LOG_WARNING", "Invalid login attempt: '%s'", ($uid||''));
 226                 print("Invalid login$CRLF");
 227         }
 228     }; # End of eval
 229
 230     if ($@) {
 231                 syslog("LOG_ERR", "telnet_transport: Login timed out");
 232                 die "Telnet Login Timed out";
 233     } elsif (!defined($account)) {
 234                 syslog("LOG_ERR", "telnet_transport: Login Failed");
 235                 die "Login Failure";
 236     } else {
 237                 print "Login OK.  Initiating SIP$CRLF";
 238     }
 239
 240     $self->{account} = $account;
 241     syslog("LOG_DEBUG", "telnet_transport: uname/inst: '%s/%s'", $account->{id}, $account->{institution});
 242     $self->sip_protocol_loop();
 243     syslog("LOG_INFO", "telnet_transport: shutting down");
 244 }
 245
 246 #
 247 # The terminal has logged in, using either the SIP login process
 248 # over a raw socket, or via the pseudo-unix login provided by the
 249 # telnet transport.  From that point on, both the raw and the telnet
 250 # processes are the same:
 251 sub sip_protocol_loop {
 252         my $self = shift;
 253         my $service = $self->{service};
 254         my $config  = $self->{config};
 255         my $input;
 256
 257     # The spec says the first message will be:
 258         #       SIP v1: SC_STATUS
 259         #       SIP v2: LOGIN (or SC_STATUS via telnet?)
 260     # But it might be SC_REQUEST_RESEND.  As long as we get
 261     # SC_REQUEST_RESEND, we keep waiting.
 262
 263     # Comprise reports that no other ILS actually enforces this
 264     # constraint, so we'll relax about it too.
 265     # Using the SIP "raw" login process, rather than telnet,
 266     # requires the LOGIN message and forces SIP 2.00.  In that
 267         # case, the LOGIN message has already been processed (above).
 268         #
 269         # In short, we'll take any valid message here.
 270         #my $expect = SC_STATUS;
 271     my $expect = '';
 272     my $strikes = 3;
 273     while ($input = Sip::read_SIP_packet(*STDIN)) {
 274                 # begin input hacks ...  a cheap stand in for better Telnet layer
 275                 $input =~ s/^[^A-z0-9]+//s;     # Kill leading bad characters... like Telnet handshakers
 276                 $input =~ s/[^A-z0-9]+$//s;     # Same on the end, should get DOSsy ^M line-endings too.
 277                 while (chomp($input)) {warn "Extra line ending on input";}
 278                 unless ($input) {
 279                         if ($strikes--) {
 280                                 syslog("LOG_ERR", "sip_protocol_loop: empty input skipped");
 281                                 next;
 282                         } else {
 283                                 syslog("LOG_ERR", "sip_protocol_loop: quitting after too many errors");
 284                                 die "sip_protocol_loop: quitting after too many errors";
 285                         }
 286                 }
 287                 # end cheap input hacks
 288                 my $status = Sip::MsgType::handle($input, $self, $expect);
 289                 if (!$status) {
 290                         syslog("LOG_ERR", "sip_protocol_loop: failed to handle %s",substr($input,0,2));
 291                         die "sip_protocol_loop: failed Sip::MsgType::handle('$input', $self, '$expect')";
 292                 }
 293                 next if $status eq REQUEST_ACS_RESEND;
 294                 if ($expect && ($status ne $expect)) {
 295                         # We received a non-"RESEND" that wasn't what we were expecting.
 296                     syslog("LOG_ERR", "sip_protocol_loop: expected %s, received %s, exiting", $expect, $input);
 297                         die "sip_protocol_loop: exiting: expected '$expect', received '$status'";
 298                 }
 299                 # We successfully received and processed what we were expecting
 300                 $expect = '';
 301         }
 302 }
 303
 304 1;
 305 __END__