#!/usr/local/bin/perl
$|=1;

# birdseye.cgi: a simple server and network utility script
# Release 1.0 on 10/22/98                                         
# (C) 1998 BigNoseBird.Com, Inc. This program is freeware and may
# be used at no cost to you (just leave this notice intact).
# Feel free to modify, hack, and play  with this script. Just 
# be very, very careful what you choose to run. This script is
# offered AS-IS with no warranties or guarantees. In other words,
# you are alone responsible for the use or misuse of this script.
# If you are able to, please test all command line programs via
# telnet at the unix prompt before placing them in the script.

##################################################################
#
#      INSTRUCTIONS
#
# Upload this file to your cgi-bin enabled directory. 
# If you are using a PC or Mac to access a unix server, be sure
# to upload the script as an ASCII file and not as BINARY.
# It is important to read the CONFIGURATION section carefully.
# The only items you need to set are the commands, the number
# of seconds the script should run before stopping, and the
# valid domains that can call the script.
#
# The birdseye.html form only has to provide at the most, two
# items- program and target.

##################################################################
#
#      CONFIGURATION SECTION
#
#The maximum number of seconds this script should run before quiting.
#It is important to do this, so that you do not create a denial of
#service attack on yourself or others if you use the wrong ping
#options. Some commands, such as a traceroute against a firewall
#can go on for quite a while before the maximum hops are reached.
#set this to a reasonable value.

$SECONDS=75;

#Just in case we do not want to provide the use of this script to
#other site's pages..... Place your domain information in the array
#below. Use only lower case letters!
#to activate, remove the # (comment character) at the start of the line.

@OKAYDOMAINS=('http://yourdomain.com', 'http://www.yourdomain.com');

# put your list of commands here. the first column is the code you
# will put in your form for program, ie value="1". The H at the start
# of a code indicates that an argument,ie host name MUST be specified.
# If no hostname (target) is specified by the user, then the CGI
# environment variable 'REMOTE_ADDR' will be used- the user's current
# IP address.
#
# The actual locations of various utility programs vary from server
# to server. PLEASE. Do not write asking where yours are. Write to
# your server administrator, or telnet to your site and use the 
# 'which' command to get the information.
# The examples below are particular to our site.

  %commands = (
    '1', '/usr/etc/ping -c 5 ',
    '2', '/usr/local/bin/traceroute ',
    'H3', '/usr/local/bin/whois ',
    'H4', '/usr/bsd/finger ',
     '5', '/bin/sar ',
     '6', '/usr/bsd/uptime '
              );

# REMEMBER! The 'H' in the command code means that the user must
# enter something in the 'target' field.

# you can also use this script as your own personal website monitor.
# for security reasons, you might want to htaccess protect the page
# calling these functions. Also, use wierd values for the program 
# codes so people can't try and guess them. Trust me, these are not
# the values on my server. ;-)
#
# IMPORTANT!  Do NOT use an 'H' in the codes listed below.
#
# These are examples only. You can do whatever you want, but do
# be careful. To add more programs to the %command list above,
# stick them between traceroute and whois to avoid making 
# punctuation errors, ie, the commas at the end of all lines but
# the last. Also, all items must be entered as pairs.

   'Z1AB2', "/bin/who -u",   #display users on line along with idle time
   'UA81R', "/bin/netstat",  #show server network connection status
   'DVJ87', "/bin/ps -ef",   #show all system processes
   '87UYY', "/bin/sar ; /bin/ps -ef", #run both sar and ps commands

#HINTS! In Linux, "ps axef" will give you a cool process tree. The -ef
#       option does not act the same as most other flavors of unix.
#       Linix also does not have a sar command.

##################################################################
#       THERE IS NOTHING YOU NEED DO BEYOND THIS POINT
##################################################################
# and let the script begin!

# to prevent runaways, call it quits after SECONDS seconds.

  $SIG{'ALRM'} =\&alarm_handle;
  alarm($SECONDS ? $SECONDS : 1);     

  &valid_page;

  &decode_vars;

  if ($TARGET_HOST eq "" && $PROGRAM =~/H/)
    {print "Content-type: text/html\n\n";
     print "\nNo argument was sent to the command\n";
     exit 0;           
    }

  if ($TARGET_HOST eq "" && $PROGRAM !=~/H/ 
        && $ENV{'REQUEST_METHOD'} eq "POST")
    { $TARGET_HOST=$ENV{'REMOTE_ADDR'}; }

  if ($commands{$PROGRAM} eq "")
    {print "Content-type: text/html\n\n";
     print "\nNo command was specified...";
     exit 0;           
    }

   &run_command;
   exit;
##################################################################
sub run_command
{
   print "Content-type: text/html\n\n";
   print "<HTML><PRE>\n";
   print "<B>Please wait for script to run, or time out</B>\n";
   if ($TARGET_HOST ne "")
    { print "<B>RESULTS OF $commands{$PROGRAM} on $TARGET_HOST</B>\n\n";}
    else
    { print "<B>RESULTS OF $commands{$PROGRAM}</B>\n\n";}
   open (IX,"$commands{$PROGRAM} $TARGET_HOST |");
   while (<IX>)
    {
       chop $_;
       print "$_\n";
    }
   print <<__END_OF_FOOTER__;
   </PRE>
   <B>Done! Press your back button to return or
   <A HREF="$ENV{'HTTP_REFERER'}">Click Here</A>.</B>
   <P>
   <B><I>Birdseye.cgi</I> is another free script from
   <A HREF="http://bignosebird.com/">BigNoseBird.Com</A></B>
   </HTML>
__END_OF_FOOTER__
   close (IX);
}

##################################################################
sub alarm_handle        
{                  
  alarm(0);        
  terminate();     
}                  
                   
##################################################################
sub terminate      
{                  
 print "Content-type: text/html\n\n";
 print "\nYour request exceeded the maximum time limit...\n";
 exit 0;           
}                  

##################################################################
# special security items.
# 1. only allow legal characters in.
# 2. we do not have to worry about bogus commands being passed
#    since we are using a hash with codes for the actual system
#    commands.
# 3. change the code below at your own risk of server death!

sub decode_vars
{
  $i=0;
  if ( $ENV{'REQUEST_METHOD'} ne "POST")
   { $temp=$ENV{'QUERY_STRING'};}
   else { read(STDIN,$temp,$ENV{'CONTENT_LENGTH'});}                                          
  @pairs=split(/&/,$temp);
  foreach $item(@pairs)
   {
    ($key,$content)=split(/=/,$item,2);
    $content=~tr/+/ /;
    $content=~s/%(..)/pack("c",hex($1))/ge;
    $content=~s/\012//g;
    $content=~s/\015//g;
    $content=~s/ //g;
    $fields{$key}=$content;
   }

  $PROGRAM=$fields{'program'};

  if ($fields{'target'}=~ /^([-\@\w.]+)$/ || $fields{'target'} eq "") 
    {$TARGET_HOST=$fields{'target'};
     return;
    }
    else 
     {$TARGET_HOST="";
      print "Content-type: text/html\n\n";
      print "Illegal Character(s) sent...";      
      exit;
     }                                              
}

##################################################################
sub valid_page
{
 if (@OKAYDOMAINS == 0) {return;}
  $DOMAIN_OK=0;
  $RF=$ENV{'HTTP_REFERER'};
  $RF=~tr/A-Z/a-z/;
  foreach $ts (@OKAYDOMAINS)
   {
     if ($RF =~ /$ts/) { return; }
   }
  if ( $DOMAIN_OK == 0)
   { print "Content-type: text/html\n\n Sorry, can't do this from here....";
     exit;
   }
}