#! /usr/bin/perl
# 
# backupConfig.pl is a PERL script intended to copy the current running config
# of an IOS Cisco device to a specified TFTP server. The name of the config is 
# constructed using the IP address of the device, and appending the string 
# "-config" to it. The username, password and enable password must be supplied 
# for each device specified as an IP address. The script is adapted from the 
# examples at http://nettelnetcisco.sourceforge.net/docs.html
#
# Versions
# --------
# 0.1	-	Initial version
# 0.2	-	Uses only just-in-time processing for devices from config file
# 0.3	-	Performs local write to file of running config
#
# Note: The TFTP component of the script has not been tested and has been 
# commented out. The file only performs a write to a local file of the running
# config and displays the running confirm to STDOUT.
#

use Net::Telnet::Cisco;
use strict;
use warnings;



#
# Global variables
#
my $tftp_server = "192.168.1.1";
my $config = "backupConfig.txt";
my $DEBUG = 0;
my $INFO = 0;



#
# backupConfig sub-routine opens the config tile and parses it to constucts a list
# of devices together with the login and enable credentials. Each line in the 
# config file must specify the IP address of the device, the type of the device,
# the IOS version of the device, the logon username, the logon password and the 
# enable password. Each field must be separated by a sequence of ~~~ characters 
# e.g.;
# "192.168.1.254"~~~"router"~~~"12"~~~"noc"~~~"password"~~~"en-password"
# "192.168.1.253"~~~"switch"~~~"12"~~~"noc"~~~"password"~~~"en-password"
#
sub backupConfig {
	# debug code trace
	if ( $DEBUG ) { printf( "DEBUG: backupConfig()\n" ); }

	# open the config file or die trying :)
	open( CONFIG, "<".$config ) or die( "DIE: Unable to open config file : " . $config );

	while( <CONFIG> ) {
		# read the line
		my $lineRead = $_;
		chomp( $lineRead );
		if ( $DEBUG ) { printf( "DEBUG: backupConfig - $lineRead\n" ); }

		# split the line into fields
		my @splitFields = split( "~~~", $lineRead );
		if ( $DEBUG ) { printf( "DEBUG: backupConfig - @splitFields\n" ); }
		my $ipAddress = $splitFields[0];
		my $deviceType = $splitFields[1];
		my $iosVersion = $splitFields[2];
		my $username = $splitFields[3];
		my $password = $splitFields[4];
		my $enPassword = $splitFields[5];

		# attempt to get the config for the device
		processDevice( $ipAddress, $deviceType, $iosVersion, $username, $password, $enPassword );
	}

	# close the file
	close( CONFIG );
}



# 
# executeCmd is a sub-routine to execute a specified command on the Cisco 
# device specified. The command, the device IP address, and the login credentials
# must be supplied
#
# @param cmd	- the command to be executed on the device
# @param host	- the IP address of the Cisco device
# @param username	- the initial device login username
# @param password	- the initial device login password
# @param enablePass	- the enable/privilege device login password
#
# @returns Array	- array of Strings representing the output of the command 
#
sub executeCmd {
	# debug code trace
	if ($DEBUG) { printf( "DEBUG: executeCmd()\n" ); }

	# get function paramaters
	my $cmd = shift;
	my $host = shift;
	my $username = shift;
	my $password = shift;
	my $enablePass = shift;

	# validate parameters
	if ( !defined( $cmd )) {
		printf( "ERROR: executeCmd() - Command not defined\n" ); 
		return;
	}
	if ( !defined( $host )) {
		printf( "ERROR: executeCmd() - Host not defined\n" );
		return;
	}
	if ( !defined( $username )) {
		printf("ERROR: executeCmd() - Username not defined\n");
		return;
	}
	if ( !defined( $password )) {
		printf("ERROR: executeCmd() - Password not defined\n");
		return;
	}
	if ( !defined( $enablePass )) {
		printf("ERROR: executeCmd() - Enable password not defined\n");
		return;
	}
	if ( $INFO ) { printf( "INFO: executeCmd( $cmd, $host, $username, $password, $enablePass )\n" ); }

	# connect to cisco device
	my $session = Net::Telnet::Cisco->new( Host => $host );
	$session->login( $username, $password );

	# escalate privilege
	my @output;
	if ( $session->enable( $enablePass )) {
		# execute the command and capture output
		@output = $session->cmd( $cmd );

		if ( $INFO ) {
			foreach ( @output ) {
  				print "$_";
			}
		}
	} else {
		printf( "ERROR: executeCmd() - Unable to escalate privileges\n" );
    		warn "WARN : Unable to escalate privileges : " . $session->errmsg;
	}

	# close session to cisco device
	$session->close;
	return \@output;
}



#
# getTFTPCmd is a sub-routine to construct the appropriate command string for 
# the host supplied. The type of device and the IOS version must also be supplied
#
# @param host	- the IP address of the Cisco device
# @param ver	- the major IOS version number, {12,11,10}
# @param type	- the Cisco device type, {"router","switch"}
#
# @returns String	- the command string to copy the config to the tftp server
#
sub getTFTPCmd {
	# debug code trace
	if ( $DEBUG ) { printf( "DEBUG: getTFTPCmd()\n" ); }

	# get function parameters
	my $host = shift;
	my $type = shift;
	my $ver = shift;
	my $cmd = "";

	# validate parameters
	if ( !defined( $host )) {
		printf( "ERROR: getTFTPCmd() - Host not defined\n" );
		return undef;
	}
	if ( !defined( $type )) {
		printf( "ERROR: getTFTPCmd() - Device type not defined\n" );
		return;
	}
	if ( !defined( $ver )) {
		printf( "ERROR: getTFTPCmd() - IOS version not defined\n" );
		return;
	}
	if ( $INFO ) { printf( "INFO: getTFTPCmd( $host, $type, $ver )\n" ); }


	# determine type of device
  	if ( $type eq "router" ) {
		# check ios version and construct command
      		if ( $ver >= 12 ) {
			$cmd = "copy system:/running-config tftp://$tftp_server/$host-config\n\n\n";
      		} elsif ( $ver >= 11 ) {
          		$cmd = "copy running-config tftp\n$tftp_server\n$host-config\n";
      		} elsif ( $ver >= 10 ) {
          		$cmd = "write net\n$tftp_server\n$host-config\n\n";
      		}
  	} elsif ( $type eq "switch" ) {
      		$cmd = "copy system:/running-config tftp://$tftp_server/$host-config\n\n\n";
  	}

	# return the TFTP command as a string
	if ( $INFO ) { printf( "INFO: getTFTPCmd() - \"$cmd\"\n" ); }
	return $cmd
}



#
# processDevice sub-routine performs the backup of the config on the on the Cisco
# device specified. The IP address of the host, the type of device, the version 
# of the IOS, the logon username and password, and the enable password must be 
# supplied. The TFTP command is executed on the device, along with a write of the
# current running config to the backup file. The backup filename is constructed 
# using the IP address of the device, and appending the string "-config" to it.
#
# @param ipAddress 	- the IP address of the Cisco device
# @param deviceType	- the Cisco device type, {"router","switch"}
# @param iosVersion	- the major IOS version number, {12,11,10}
# @param username	- the logon username
# @param password	- the logon password
# @param enPassword	- the enable password
#
sub processDevice {
	# debug code trace
	if ( $DEBUG ) { printf( "DEBUG: processDevice()\n" ); }

	# get function paramaters
	my $ipAddress = shift;
	my $deviceType = shift;
	my $iosVersion = shift;
	my $username = shift;
	my $password = shift;
	my $enPassword = shift;

	# validate paramaters
	if ( !defined( $ipAddress )) {
		printf( "ERROR: processDevice() - Host not defined\n" );
		return;
	}
	if ( !defined( $deviceType )) {
		printf( "ERROR: processDevice() - Device type not defined\n" );
		return;
	}
	if ( !defined( $iosVersion )) {
		printf( "ERROR: processDevice() - IOS version not defined\n" );
		return;
	}
	if ( !defined( $username )) {
		printf( "ERROR: processDevice() - Username not defined\n" );
		return;
	}
	if ( !defined( $password )) {
		printf( "ERROR: processDevice() - Password not defined\n" );
		return;
	}
	if ( !defined( $enPassword )) {
		printf( "ERROR: processDevice() - Enable password not defined\n" );
		return;
	}
	if ( $INFO ) { printf( "INFO: processDevice( $ipAddress, $deviceType, $iosVersion, $username, $password, $enPassword )\n" ); }

	# get the TFTP command and execute on the cisco device
	#my $cmd = getTFTPCmd( $ipAddress, $deviceType, $iosVersion );
	#executeCmd( $cmd, $ipAddress, $username, $password, $enPassword );

	# get a running config and write to a local file
	$cmd = "show run";
        my $running_config = executeCmd( $cmd, $ipAddress, $username, $password, $enPassword );

	foreach my $dataLine ( @{$running_config} ) {
  		printf("%s", $dataLine );
	}

	writeToFile( $ipAddress."-config", $running_config );
}



#
# writeToFile sub-routine writes the data supplied as an array of String to the
# file created using the filename supplied
#
# @param $filename	- String representing the name of the file to write to
# @param @data	- array of Strings 
#

sub writeToFile {
	# debug code trace
	if ( $DEBUG ) { printf( "DEBUG: writeToFile()\n" ); }

	# get function parameters
	my $filename = shift;
	my $data_ref = shift;

	# validate function paramaters
	if ( !defined( $data_ref )) {
		printf( "ERROR: writeToFile() - Data not defined\n" );
		return;
	}
	if ( !defined( $filename )) {
		printf( "ERROR: writeToFile() - Filename not defined\n" );
		return;
	}

	# create file with filename
	open( DATA, ">$filename" );
	foreach ( @{$data_ref} ) {
  		print DATA "$_";
	}
	close( DATA );
}


backupConfig();