#!/user/bin/perl

###########################################################################
#                                                                         #
#        GateKeeper                                                       #
#                                                                         #
#        (C) 2016 Domero, Groningen, NL                                   #
#        chaosje@gmail.nl                                                 #
#                                                                         #
#        ALL RIGHTS RESERVED                                              #
#                                                                         #
###########################################################################

use gserv;
use grand qw(rand randomhex);
use gutil qw(validip gettime);

my $ESQUIT=0;

$SIG{INT}=\&stopserver;
$SIG{PIPE}=\&clientquit;
$SIG{__DIE__}=\&fatalerror;
$SIG{__WARN__}=\&warning;

my @ALLOWED=();
my $SERVPASS = "Vg5ks4d7JuBnWqsTFFsLpQYkGffW67Gbc9m0feEg65";

my $serv=gserv::init(\&handleinput,\&handleloop);
$serv->{name}="GateKeeper v1.0.1 (C) 2016 Domero";
$serv->{pingtime}=10;
$serv->{pingtimeout}=10;
$serv->{server}{port}=7010;
$serv->{idletimeout}=30;
$serv->{allowedip}= [ '127.0.0.1','94.212.45.34','141.138.137.123' ];

open OUTPUT, '>>', "gatekeeper.log" or die "Can't create filehandle: $!";

$serv->start;
while (!$ESQUIT) {
  $serv->takeloop();
}

sub fatalerror {
  print OUTPUT "!!!! FATAL ERROR !!!! $!";
  $ESQUIT=1
}

sub warning {
  print OUTPUT "!! WARNING !! $!";
}

sub stopserver { print OUTPUT "** Shutting down server!!!!\n"; $ESQUIT=1 }

sub clientquit {
  if ($serv->{activeclient}) {
    $serv->{activeclient}{killme}=1;
  }
}

sub addclient {
  my ($ip,$pass,$verify) = @_;
  my $client={
    ip => $ip, pass => $pass, verify => $verify
  };
  push @ALLOWED,$client
}

sub delclient {
  my ($ip,$port) = @_;
  my $i=0;
  while ($i<=$#ALLOWED) {
    print $ALLOWED[$i]{ip}."\n"; 
    if (($ALLOWED[$i]{ip} eq $ip) && ($ALLOWED[$i]{port} eq $port)) {
      splice(@ALLOWED,$i,1); return
    }
    $i++
  }
}

sub search {
  my ($verify) = @_;
  foreach my $client (@ALLOWED) {
    if ($client->{verify} eq $verify) {
      return $client
    }
  }
  return {}
}

sub checkip {
  my ($ip) = @_;
  foreach my $client (@ALLOWED) {
    if ($client->{ip} eq $ip) {
      return 1
    }
  }
  return 0
}

sub handleinput {
  my ($command,$client,$data) = @_;
  if ($command eq 'connect') {
    if (!checkip($client->{ip})) {
      print OUTPUT gettime()." !! ATTACK $client->{ip}:$client->{port}\n";
      $client->{killme}=1
    }
  } elsif ($command eq 'input') {
    if (!length($data)) { return }
    if ($data =~ /^login ([a-zA-Z0-9]+) ([0-9\.]+)$/) {
      if (($1 eq $SERVPASS) && (validip($2))) {
        my $pass=randomhex(rand(100)+150);
        my $verify=randomhex(20);
        addclient($2,$pass,$verify);
        gserv::out($client,$pass." ".$verify);
        print OUTPUT gettime()." CREATE $pass for $2\n"
      }
    } elsif ($data =~ /^getpass ([0-9A-Z]{20})$/) {
      my $verify=$1;
      my $check=search($verify);
      if ($check->{ip} eq $client->{ip}) {
        gserv::out($client,$check->{pass});
        print OUTPUT gettime()." SERVED $client->{ip}:$client->{port}\n";
        $client->{killme}=1
      } else {
        print OUTPUT gettime()." ** ILLEGAL REQUEST $client->{ip}:$client->{port} $verify\n";
        $client->{killme}=1
      }
    }
  } elsif ($command eq 'error') {
    print OUTPUT gettime()." ERROR $client->{ip}:$client->{port} $data\n"
  } elsif ($command eq 'quit') {
    print OUTPUT gettime()." QUIT $client->{ip}:$client->{port}\n";
    delclient($client->{ip},$client->{port})
  }
}

sub handleloop {
  my ($client) = @_;

}