#!/usr/bin/perl
# **********************************************************************
# Pandora FMS Generic Unix/Perl Agent
# (c) 2009-2011 Artica Soluciones Tecnológicas
# with the help of many people. Please see http://pandorafms.org
# This code is licensed under GPL 2.0 license.
# **********************************************************************

=head1 NAME

pandora_agent - Pandora FMS Agent

=head1 VERSION

Version 4.0

=head1 USAGE

<< pandora_agent F<pandora home> >>

=cut
package PerlSvc;

use strict;
use warnings;

use POSIX qw(strftime floor);
use Sys::Hostname;
use File::Basename;
use File::Copy;
use IO::Socket;

# Agent XML data
my $Xml;

# Semaphore used to acces $Xml
my $Sem = undef;

# Semaphore used to control the number of threads
my $ThreadSem = undef;

# Load thread support
eval {
	local $SIG{__DIE__};
	require threads;
	require threads::shared;
	require Thread::Semaphore;
};
if (!$@) {
	$Sem = Thread::Semaphore->new;
	threads::shared::share (\$Xml);
	threads::shared::share (\$Sem);
}	

use constant AGENT_VERSION => '4.0.1';
use constant AGENT_BUILD => '111213';

# Commands to retrieve total memory information in kB
use constant TOTALMEMORY_CMDS => {
	linux => 'cat /proc/meminfo | grep MemTotal: | awk \'{ print $2 }\'',
	solaris => '/usr/sbin/prtconf | awk \'/Memory/ { print $3 * 1024 }\'',
	hpux => 'swapinfo -t | grep memory | awk \'{print $2}\'',
	freebsd => '/sbin/sysctl hw.physmem | awk \'{print $2 / 1024}\'',
};

# Commands to retrieve free memory information in kB
use constant FREEMEMORY_CMDS => {
	linux => 'cat /proc/meminfo | grep MemFree: | awk \'{ print $2 }\'',
	solaris => 'vmstat 1 2 | tail -1 | awk \'{ print $5 }\'',
	hpux => 'swapinfo -t | grep memory | awk \'{print $4}\'',
	freebsd => '/sbin/sysctl -n vm.stats.vm.v_page_size vm.stats.vm.v_free_count | tr "\n" " " | awk \'{ print $1 * $2 / 1024 }\'',
};

# Commands to retrieve cpu information
use constant CPUUSAGE_CMDS => {
	linux => 'vmstat 1 2 | tail -1 | awk \'{ print $13 }\'',
	solaris => 'vmstat 1 2 | tail -1 | awk \'{ print $21 }\'',
	hpux => 'vmstat 1 2 | tail -1 | awk \'{ print $16 }\'',
	freebsd => 'vmstat -n 0 1 2 | tail -1 | awk \'{ print $15 }\''
};

# Commands to retrieve process information
use constant PROC_CMDS => {
	# cpu usage, memory usage, command name
	linux => 'ps aux | awk \'NR > 1 {ps = ""; for (i = 11; i <= NF; ++i) {ps = (ps " " $i) }; print $3, $6, ps}\'',
	solaris => 'prstat 1 1 | awk \'NR > 1 {split ($10, ps, "/"); cpu = substr ($9, 1, length ($9) - 1); mem = substr ($3, 1, length ($3) - 1); print cpu, mem, ps[1]}\'',
	hpux => 'ps -elf | awk \'NR > 1 {ps = ""; for (i = 15; i <= NF; ++i) {ps = (ps " " $i) }; print 0, $10, ps}\'',
	aix => 'ps aux | awk \'NR > 1 {print $3, $6, $11}\'',
	freebsd => 'ps axww -o %cpu= -o %mem= -o command= | sed -e "s/^ *//"',
};

# Commands to retrieve partition information in kB
use constant PART_CMDS => {
	# total, available, mount point
	linux => 'df -P | awk \'NR > 1 {print $2, $4, $6}\'',
	solaris => 'df -k | awk \'NR > 1 {print $2, $4, $6}\'',
	hpux => 'df -P | awk \'NR > 1 {print $2, $4, $6}\'',
	aix => 'df -kP | awk \'NR > 1 {print $2, $4, $6}\'',
	freebsd => 'df -k | awk \'NR > 1 {print $2, $4, $6}\''
};

# Commands to call df with POSIX output format
use constant DF_CMDS => {
	# total, available, mount point
	linux => 'df -P',
	solaris => 'df -k',
	hpux => 'df -P',
	aix => 'df -kP',
	freebsd => 'df -k'
};
	
# Used to calculate the MD5 checksum of a string
use constant MOD232 => 2**32;

# Directory where pandora_agent.conf is located
my $ConfDir = '';

# Pandora FMS agent configuration file
my $ConfFile = 'pandora_agent.conf';

# Broker agent configuration files
my @BrokerPid;

# Configuration tokens
my %Conf = (
	'server_ip' => 'localhost',
	'server_path' => '/var/spool/pandora/data_in',
	'logfile' =>'/var/log/pandora/pandora_agent.log',
	'temporal' => '/var/spool/pandora',
	'interval' => 300,
	'debug' => 0,		
	'agent_name' => hostname (),
	'description' => '',
	'group' => '',
	'encoding' => 'ISO-8859-1',
	'server_port' => 41121,
	'transfer_mode' => 'tentacle',
	'server_pwd' => '',
	'server_ssl' => 'no',
	'server_opts' => '',
	'delayed_startup' => 0,
	'pandora_nice' => 10,
	'cron_mode' => 0,
	'remote_config' => 0,
	'secondary_mode' => 'never',
	'secondary_server_ip' => 'localhost',
	'secondary_server_path' => '/var/spool/pandora/data_in',
	'secondary_server_port' => 41121,
	'secondary_transfer_mode' => 'tentacle',
	'secondary_server_pwd' => '',
	'secondary_server_ssl' => 'no',
	'secondary_server_opts' => '',
	'autotime' => 0,
	'temporal_min_size' => 1,
	'timezone_offset' => 0,
	'pandora_exec' => 'pandora_agent_exec',
	'agent_threads' => 1,
	'udp_server_port' => 41122,
	'udp_server_auth_address' => '0.0.0.0',
	'udp_server' => 0,
	'proxy_mode' => 0,
	'proxy_max_connection' => 10,
	'proxy_timeout' => 1,
	'intensive_interval' => 0,
	'timestamp' => 0,
	'xml_buffer' => 0,
	'win32_monitoring_lib' => 'WMI',
);

# Service configuration;
our %Config = (ServiceName => "pandoraFMSagent",
	           DisplayName => "Pandora FMS Agent",
	           Description => "Pandora FMS Agent",
	);

# Modules
my @Modules;

# Plugins
my @Plugins;

# Logfile file handle
my $LogFileFH;

# Agent name MD5;
my $AgentMD5;

# Remote configuration file name
my $RemoteConfFile;

# Remote md5 file name
my $RemoteMD5File;

# Process data
my %Procs = (
	'__utimestamp__' => 0
);

# Partition data
my %Parts = (
	'__utimestamp__' => 0
);

# Collections
my %Collections;

# $DevNull
my $DevNull = '/dev/null';

# Shell command separator
my $CmdSep = ';';

# PID of tentacle proxy, used in proxy mode
my $tentacle_pid = undef;

# OS and OS version
my $OS = $^O;
my $OS_VERSION = guess_os_version ($OS);

# Windows specific modules
my $Win32 = undef;
if ($OS eq 'windows') {
	require PandoraWin32;
	PandoraWin32->import();
}

################################################################################
# Print usage information and exit.
################################################################################
sub print_usage () {
	print "\nUsage: $0 <Pandora home>\n\n";
	print "\tPandora home is the directory where pandora_agent.conf is located,\n";
	print "\tby default /etc/pandora.\n\n";
}

################################################################################
# Print an error message and exit.
################################################################################
sub error ($) {
	my $msg = shift;
	print ("[ERROR] $msg\n\n");
	`logger -i -t pandora_agent_daemon [ERROR] $msg 2>/dev/null`;
}

################################################################################
# Check a regular expression. Returns 1 if its valid, 0 otherwise.
################################################################################
sub valid_regexp ($) {
	my $regexp = shift;
	
	eval {
		'' =~ /$regexp/;
	};

	# Something went wrong
	return 0 if ($@);
	
	return 1;
}

################################################################################
# Recursively delete files and directories.
################################################################################
sub rmrf {
	my $path = shift;
	local *DIR;

	if (-d $path) {
		opendir (DIR, $path) || return;
		while (defined (my $file_name = readdir(DIR))) {
			next if ($file_name eq '.' || $file_name eq '..');
			rmrf ("$path/$file_name");
		}
		closedir (DIR);
		rmdir ($path);
	} else {
		unlink ($path);
	}
}

################################################################################
# Recursively set file permissions.
################################################################################
sub chmodr {
	my ($perm, $path) = @_;
	local *DIR;

	if (-d $path) {
		opendir (DIR, $path) || return;
		while (defined (my $file_name = readdir(DIR))) {
			next if ($file_name eq '.' || $file_name eq '..');
			chmodr ($perm, "$path/$file_name");
		}
		closedir (DIR);
	}
	chmod ($perm, $path);
}

################################################################################
# Open the agent logfile and start logging.
################################################################################
sub start_log (;$) {
	my $quiet = shift;

	# Get the logfile
	my $log_file_name = read_config ('logfile');
	$log_file_name = '/var/log/pandora/pandora_agent.log' unless defined ($log_file_name);

	# Open it
	if (! open ($LogFileFH, "> $log_file_name")) {
		error ("Could not open log file '$log_file_name' for writing: $!.");
	} elsif (! defined ($quiet)) {
		print "Logging to $log_file_name\n";
	}
}

################################################################################
# Close the agent logfile and stop logging.
################################################################################
sub stop_log () {
	close ($LogFileFH);
}

################################################################################
# Log a message to the agent logfile.
################################################################################
sub log_message ($$;$) {
	my ($source, $msg, $dest) = @_;
	
	if (defined ($dest)) {
		print $dest strftime ('%Y/%m/%d %H:%M:%S', localtime ()) . " - [$source] - $msg\n";
	} else {
	
		#  Check if the filehandle is open
		if (! defined (fileno ($LogFileFH))) {
			return;
		}

		#Trying to write into log file to test its writable		
		syswrite ($LogFileFH, "");
		
		#If no error, the file is writable
		if (!$!) {
			print $LogFileFH strftime ('%Y/%m/%d %H:%M:%S', localtime ()) . " - [$source] - $msg\n";
		} else {
			#If error then log into syslog!
			`logger -i -t pandora_agent_daemon [ERROR] $msg 2>/dev/null`;
		}
	}
}

################################################################################
# Add the given directory to the PATH.
################################################################################
sub add_dir_to_path {
	my $dir = shift;
	
	if ($OS eq 'windows') {
		#  Replace / with \
		$dir =~ s/\//\\/g;
		$ENV{'PATH'} .= ";$dir";
	} else {
		$ENV{'PATH'} .= ":$dir";
	}
}
################################################################################
# Parse configuration file (modules, plugins and collections)
################################################################################
sub parse_conf_modules($) {
	my ($param) = @_;
	my $module;
	
	foreach my $line (@{$param}) {
		
		next if ($line =~ m/^\s*#/) or ($line =~ m/^\s*$/);
		# Module definition
		if ($line =~ /^\s*module_begin\s*$/) {
			$module = {
				'name' => '',
				'type' => 'generic_data',
				'description' => '',
				'func' => 0,
				'params' => '',
				'description' => '',
				'interval' => 1,
				'timeout' => 0,
				'counter' => 0,
				'max' => undef,
				'min' => undef,
				'post_process' => undef,
			    'min_critical' => undef,
			    'max_critical' => undef,
			    'min_warning' => undef,
			    'max_warning' => undef,
			    'disabled' => undef,
			    'min_ff_event' => undef,
				'save' => '',
				'conditions' => [],
				'cron' => '',
				'cron_utimestamp' => 0,
				'cron_interval' => -1,
				'precondition' => [],
				'is_intensive' => 0,
				'intensive_conditions' => [],
				'intensive_match' => 0,
				'timestamp' => 0,
			};
		} elsif ($line =~ /^\s*module_name\s+(.+)$/) {
			$module->{'name'} = $1;
		} elsif ($line =~ /^\s*module_description\s+(.+)$/) {
			$module->{'description'} = $1;
		} elsif ($line =~ /^\s*module_type\s+(\S+)\s*$/) {
			$module->{'type'} = $1;
		}elsif ($line =~ /^\s*module_precondition\s+(.*)$/) {
			my $action = $1;
			
			# Numeric comparison
			if ($action =~ /^\s*([<>!=]+)\s+(\d+(?:\.\d*)?)\s+(.*)$/) {
				push (@{$module->{'precondition'}}, {'operator' => $1, 'value_1' => $2, 'command' => $3});
			# Interval
			} elsif ($action =~ /^\s*[(]\s*(\d+(?:\.\d*)?)\s*,\s*(\d+(?:\.\d*)?)\s*[)]\s+(.*)$/) {
				push (@{$module->{'precondition'}}, {'operator' => '()', 'value_1' => $1, 'value_2' => $2, 'command' => $3});
			# Regular expression
			} elsif ($action =~ /^\s*=~\s+(\S*)\s+(.*)$/) {
				if (valid_regexp ($1)) {
					push (@{$module->{'precondition'}}, {'operator' => '=~', 'value_1' => $1, 'command' => $2});
				} else {
					log_message ('setup', "Invalid regular expression in module precondition: $line");
				}
			}
		} elsif ($line =~ /^\s*module_exec\s+(.+)$/) {
			$module->{'func'} = \&module_exec;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_cpuusage\s+(.*)$/) {
			$module->{'func'} = \&module_cpuusage;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_freememory\s+(.*)$/) {
			$module->{'func'} = \&module_freememory;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_freepercentmemory\s+(.*)$/) {
			$module->{'func'} = \&module_freepercentmemory;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_proc\s+(.+)$/) {
			$module->{'func'} = \&module_proc;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_service\s+(.+)$/) {
			$module->{'func'} = \&module_service;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_cpuproc\s+(.+)$/) {
			$module->{'func'} = \&module_cpuproc;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_memproc\s+(.+)$/) {
			$module->{'func'} = \&module_memproc;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_freedisk\s+(.*)$/) {
			$module->{'func'} = \&module_freedisk;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_freepercentdisk\s+(.*)$/) {
			$module->{'func'} = \&module_freepercentdisk;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_occupiedpercentdisk\s+(.*)$/) {
			$module->{'func'} = \&module_occupiedpercentdisk;
			$module->{'params'} = $1;
		} elsif ($line =~ /^\s*module_max\s+(.*)\s*$/) {
			$module->{'max'} = $1;
		} elsif ($line =~ /^\s*module_min\s+(.*)\s*$/) {
			$module->{'min'} = $1;
		} elsif ($line =~ /^\s*module_postprocess\s+(.*)\s*$/) {
			$module->{'post_process'} = $1;
		} elsif ($line =~ /^\s*module_interval\s+(\d+)\s*$/) {
			$module->{'interval'} = $1;
		} elsif ($line =~ /^\s*module_timeout\s+(\d+)\s*$/) {
			$module->{'timeout'} = $1;
		} elsif ($line =~ /^\s*module_save\s+(\w+)$/) {
			$module->{'save'} = $1;
		} elsif ($line =~ /^\s*module_condition\s+(.*)$/) {
			my $action = $1;
			# Numeric comparison
			if ($action =~ /^\s*([<>!=]+)\s+(\d+(?:\.\d*)?)\s+(.*)$/) {
				push (@{$module->{'conditions'}}, {'operator' => $1, 'value_1' => $2, 'command' => $3});
			# Interval
			} elsif ($action =~ /^\s*[(]\s*(\d+(?:\.\d*)?)\s*,\s*(\d+(?:\.\d*)?)\s*[)]\s+(.*)$/) {
				push (@{$module->{'conditions'}}, {'operator' => '()', 'value_1' => $1, 'value_2' => $2, 'command' => $3});
			# Regular expression
			} elsif ($action =~ /^\s*=~\s+(\S*)\s+(.*)$/) {
				if (valid_regexp ($1)) {
					push (@{$module->{'conditions'}}, {'operator' => '=~', 'value_1' => $1, 'command' => $2});
				} else {
					log_message ('setup', "Invalid regular expression in module condition: $line");
				}
			}
		} elsif ($line =~ /^\s*module_intensive_condition\s+(.*)$/) {
			my $action = $1;
			
			$module->{'is_intensive'} = 1;
			
			# Numeric comparison
			if ($action =~ /^\s*([<>!=]+)\s+(\d+(?:\.\d*)?)\s*$/) {
				push (@{$module->{'intensive_conditions'}}, {'operator' => $1, 'value_1' => $2});
			# Interval
			} elsif ($action =~ /^\s*[(]\s*(\d+(?:\.\d*)?)\s*,\s*(\d+(?:\.\d*)?)\s*[)]\s*$/) {
				push (@{$module->{'intensive_conditions'}}, {'operator' => '()', 'value_1' => $1, 'value_2' => $2});
			# Regular expression
			} elsif ($action =~ /^\s*=~\s+(\S*)\s*$/) {
				if (valid_regexp ($1)) {
					push (@{$module->{'intensive_conditions'}}, {'operator' => '=~', 'value_1' => $1});
				} else {
					log_message ('setup', "Invalid regular expression in intensive condition: $line");
				}
			}
		} elsif ($line =~ /^\s*module_crontab\s+(((\*|(\d+(-\d+){0,1}))\s*){5}).*$/) {
			$module->{'cron'} = $1;
		} elsif ($line =~ /^\s*module_end\s*$/) {
			next unless ($module->{'name'} ne '') and ($module->{'func'} != 0);

			# Set the intensive interval
			if ($module->{'is_intensive'} == 1) {				
				$module->{'intensive_interval'} = $module->{'interval'};
			} else {
				$module->{'intensive_interval'} = $module->{'interval'} * ($Conf{'interval'} / $Conf{'intensive_interval'});
			}

			# Make the module run the first time
			$module->{'counter'} = $module->{'intensive_interval'};

			push (@Modules, $module);
		# Plugin
		} elsif ($line =~ /^\s*module_plugin\s+(.+)$/) {
			push (@Plugins, $1);
		# Module proc command redefinition		
		} elsif ($line =~ /^\s*module_proc_cmd\s+(.+)$/) {
			PROC_CMDS->{$OS} = $1;
		# Module freedisk command redefinition		
		} elsif ($line =~ /^\s*module_freedisk_cmd\s+(.+)$/) {
			PART_CMDS->{$OS} = $1;
		# Collection
		} elsif ($line =~ /^\s*file_collection\s+(.+)$/) {
			my $collection = $1;
			
			# Prevent path traversal attacks
			if ($collection !~ m/(\.\.)|\//) {
				$Collections{$collection} = 0;
			}
		# Min critical
		} elsif ($line =~ /^\s*module_min_critical\s+(.*)\s*$/) {
			$module->{'min_critical'} = $1;
		# Max critical
		} elsif ($line =~ /^\s*module_max_critical\s+(.*)\s*$/) {
			$module->{'max_critical'} = $1;
		# Min warning
		} elsif ($line =~ /^\s*module_min_warning\s+(.*)\s*$/) {
			$module->{'min_warning'} = $1;
		# Max warning
		} elsif ($line =~ /^\s*module_max_warning\s+(.*)\s*$/) {
			$module->{'max_warning'} = $1;
		# Disabled
		} elsif ($line =~ /^\s*module_disabled\s+(.*)\s*$/) {
			$module->{'disabled'} = $1;
		# Min ff event
		} elsif ($line =~ /^\s*module_min_ff_event\s+(.*)\s*$/) {
			$module->{'min_ff_event'} = $1;
		}
	}
	return;
}

################################################################################
# Create configuration file for broker agents.
################################################################################
sub write_broker_conf($){
	my ($broker_agent) = @_;
	my $content = '';

	if (! open (CONF_FILE, "$ConfDir/$ConfFile")) {
		error ("Could not open file '$ConfDir/$ConfFile': $!.");
		return 1;
	}
	
	if (! open (BROKER_FILE, ">$ConfDir/${broker_agent}.conf")) {
		error ("Could not write configuration file: $!");
		return 1;
	}

	while (my $line = <CONF_FILE>){

		# Skip broker definitions
		if ($line =~ m/^\s*broker_agent/) {
			next;
		}
		
		# Change the agent name
		if ($line =~ m/^\s*#*\s*agent_name\s+/) {
			$line = "agent_name $broker_agent\n";
		}
		# Change the logfile
		elsif ($line =~ m/^\s*logfile\s+(.*)/) {
			$line = 'logfile ' . dirname ($1) . "/$broker_agent.log\n";
		}

		print BROKER_FILE $line;
	}
	close (BROKER_FILE);
	close (CONF_FILE);
	return 0;
}

################################################################################
# Read configuration file. Exit on error.
################################################################################
sub read_config (;$) {
	my $token = shift;
	my @found_tokens;
	my $module;

	if (! -e "$ConfDir/$ConfFile") {
		error ("File '$ConfDir/$ConfFile' not found.");
		return undef;
	}
	
	if (! open (CONF_FILE, "$ConfDir/$ConfFile")) {
		error ("Could not open file '$ConfDir/$ConfFile': $!.");
		return undef;
	}
	
	my @file = <CONF_FILE>;
	close(CONF_FILE);
	
	foreach my $line (@file){
		# Skip comments and empty lines
		next if ($line =~ m/^\s*#/) or ($line =~ m/^\s*$/);
		
		# Token search
		if (defined ($token)) {
			if ($line =~ /^\s*(\S+)\s+(.*)$/ && $1 eq $token) {
				
				# Multiple value token
				if (wantarray ()) {
					push (@found_tokens, $2);
				}
				# Single value token
				else {
					return $2;
				}
			}
			next;
		}
		next if ($line =~ /^module\s*\w*/);
		
		# Additional configuration file
		if ($line =~ /^include\s+(.*)\s*/) {
			log_message ('setup', "include is $1");
			$Conf{'include'} = $Conf{'include'} ? "$Conf{'include'} $1" : $1;

			foreach my $file_name (glob("$1")) {
				open (FILE, "$file_name") or next;

				log_message ('setup', "reading $file_name");
				my @file_conf = <FILE>;
				parse_conf_modules(\@file_conf); 
				close (FILE);
			}
			next;
		}

		#Configuration token
		if ($line =~ /^\s*(\S+)\s+(.*)$/) {		
			log_message ('setup', "$1 is $2");
			$Conf{$1} = $2;
			
			# Remove trailing spaces
			$Conf{$1} =~ s/\s*$//;
		}
	}

	# Token search
	if (defined ($token)) {
		
		# Multiple value token
		if (wantarray ()) {
			return @found_tokens;
		}
		
		# Single value token not found.
		return undef;
	}
	
	# Set the intensive interval
	if ($Conf{'intensive_interval'} == 0) {
		$Conf{'intensive_interval'} = $Conf{'interval'};
	}

	# Set the
	if ($OS eq 'windows') {
		$Win32 = PandoraWin32->new ($Conf{'win32_monitoring_lib'});
	}
	
	# Module, plugin and collection definitions
	parse_conf_modules(\@file);

	# Update the agent MD5 since agent_name may have changed
	$AgentMD5 = md5 ($Conf{'agent_name'});
	$RemoteConfFile = "$AgentMD5.conf";
	$RemoteMD5File = "$AgentMD5.md5";
	
	# Set the maximun number of threads
	$ThreadSem = Thread::Semaphore->new ($Conf{'agent_threads'}) if defined ($Sem);

	# Set tentacle client options
	if ($Conf{'transfer_mode'} eq 'tentacle') {
		$Conf{'server_opts'} = '-x \'' . $Conf{'server_pwd'} . '\' ' . $Conf{'server_opts'} if ($Conf{'server_pwd'} ne '');
		$Conf{'server_opts'} = '-c ' . $Conf{'server_opts'} if ($Conf{'server_ssl'} eq 'yes');
	}

	# Set tentacle client options for secondary server	
	if ($Conf{'secondary_transfer_mode'} eq 'tentacle') {
		$Conf{'secondary_server_opts'} = '-x \'' . $Conf{'secondary_server_pwd'} . '\' ' . $Conf{'secondary_server_opts'} if ($Conf{'secondary_server_pwd'} ne '');
		$Conf{'secondary_server_opts'} = '-c ' . $Conf{'secondary_server_opts'} if ($Conf{'secondary_server_ssl'} eq 'yes');		
	}
}

#################################################################################
## Remove any trailing / from directory names.
#################################################################################
sub fix_directory ($) {
	my $dir = shift;

	my $char = chop ($dir);
	return $dir if ($char eq '/');
	return $dir . $char;
}



################################################################################
# Sends a file to the server.
################################################################################
#sub send_file ($;$) {
sub send_file {
	my ($file, $secondary) = @_;
	my $output;

	if ($Conf{'transfer_mode'} eq 'tentacle') {
 		$output = `tentacle_client -v -a $Conf{'server_ip'} -p $Conf{'server_port'} $Conf{'server_opts'} "$file" 2>&1 >$DevNull`;
	} elsif ($Conf{'transfer_mode'} eq 'ssh') {
 		$output = `scp -P $Conf{'server_port'} $file pandora@"$Conf{'server_ip'}:$Conf{'server_path'}" 2>&1 >$DevNull`;
	} elsif ($Conf{'transfer_mode'} eq 'ftp') {
		my $base = basename ($file);
		my $dir = dirname ($file);

		$output = `ftp -n $Conf{'server_ip'} $Conf{'server_port'} 2>&1 >$DevNull <<FEOF1
		quote USER pandora
		quote PASS $Conf{'server_pwd'}
		lcd "$dir"
		cd "$Conf{'server_path'}"
		put "$base"
		quit
		FEOF1`
	} elsif ($Conf{'transfer_mode'} eq 'local') {
		$output = `cp $file $Conf{'server_path'}/ 2>&1 >$DevNull`;
	}

	# Get the errorlevel
	my $rc = $? >> 8;
	if ($rc != 0) {
		log_message ('error', "Error sending file '$file': $output");
	}

	return $rc unless (defined ($secondary));

	# Send the file to the secondary server
	return $rc unless ($Conf{'secondary_mode'} eq 'always' || ($Conf{'secondary_mode'} eq 'on_error' && $rc != 0));
	
	swap_servers ();
	$rc = send_file ($file);
	swap_servers ();
	return $rc;
}

################################################################################
# Send buffered XML files.
################################################################################
sub send_buffered_xml_files () {

	# Read XML files from the temporal directory
	opendir(TEMPORAL, $Conf{'temporal'}) or return;
	while (my $xml_file = readdir(TEMPORAL)) { 
	
		# Skip non data files and symlinks
		next if ($xml_file !~ m/\.data$/ || -l "$Conf{'temporal'}/$xml_file");

		send_file ("$Conf{'temporal'}/$xml_file", 1);
	}
}

################################################################################
# Swap primary and secondary servers.
################################################################################
sub swap_servers () {
	($Conf{'server_ip'}, $Conf{'secondary_server_ip'}) = ($Conf{'secondary_server_ip'}, $Conf{'server_ip'});
	($Conf{'server_path'}, $Conf{'secondary_server_path'}) = ($Conf{'secondary_server_path'}, $Conf{'server_path'});
	($Conf{'server_port'}, $Conf{'secondary_server_port'}) = ($Conf{'secondary_server_port'}, $Conf{'server_port'});
	($Conf{'server_transfer_mode'}, $Conf{'secondary_server_transfer_mode'}) = ($Conf{'secondary_server_transfer_mode'}, $Conf{'server_transfer_mode'});
	($Conf{'server_pwd'}, $Conf{'secondary_server_pwd'}) = ($Conf{'secondary_server_pwd'}, $Conf{'server_pwd'});
	($Conf{'server_ssl'}, $Conf{'secondary_server_ssl'}) = ($Conf{'secondary_server_ssl'}, $Conf{'server_ssl'});
	($Conf{'server_opts'}, $Conf{'secondary_server_opts'}) = ($Conf{'secondary_server_opts'}, $Conf{'server_opts'});
}

################################################################################
# Receive a file from the server.
################################################################################
sub recv_file ($) {
	my $file = shift;
	my $output;

	if ($Conf{'transfer_mode'} eq 'tentacle') {
 		$output = `cd "$Conf{'temporal'}"$CmdSep tentacle_client -v -g -a $Conf{'server_ip'} -p $Conf{'server_port'} $Conf{'server_opts'} $file 2>&1 >$DevNull`;
	} elsif ($Conf{'transfer_mode'} eq 'ssh') {
 		$output = `scp -P $Conf{'server_port'} pandora@"$Conf{'server_ip'}:$Conf{'server_path'}/$file" $Conf{'temporal'} 2>&1 >$DevNull`;
	} elsif ($Conf{'transfer_mode'} eq 'ftp') {
		my $base = basename ($file);
		my $dir = dirname ($file);

		$output = `ftp -n $Conf{'server_ip'} $Conf{'server_port'} 2>&1 >$DevNull <<FEOF1
		quote USER pandora
		quote PASS $Conf{'server_pwd'}
		lcd "$Conf{'temporal'}"
		cd "$Conf{'server_path'}"
		get "$file"
		quit
		FEOF1`
	} elsif ($Conf{'transfer_mode'} eq 'local') {
		$output = `cp $Conf{'server_path'}/$file $Conf{'temporal'} 2>&1 >$DevNull`;
	}

	# Get the errorlevel
	my $rc = $? >> 8;
	if ($rc != 0) {
		log_message ('error', "Error retrieving file: $output");
	}

	return $rc;
}

################################################################################
# Check the server for a remote configuration.
################################################################################
sub check_remote_config () {

	return unless ($Conf{'remote_config'} eq '1');

	# Calculate the configuration file MD5 digest
	if (! open (CONF_FILE, "$ConfDir/$ConfFile")) {
		error ("Could not open file '$ConfDir/$ConfFile': $!.");
		return 1;
	}
	
	binmode(CONF_FILE);
	my $conf_md5 = md5 (join ('', <CONF_FILE>));
	close (CONF_FILE);

	# Remove temporary files if they exist as symlink to avoid symlink attack
	for my $file ("$Conf{'temporal'}/$RemoteMD5File", "$Conf{'temporal'}/$RemoteConfFile")  {
		error ("File '$file' already exists as a symlink and could not be removed: $!") if (-l $file && ! unlink($file));
	}

	# Get the remote MD5 file
	if (recv_file ($RemoteMD5File) != 0) {
		if (! open (MD5_FILE, "> $Conf{'temporal'}/$RemoteMD5File")) {
			error ("Could not open file '$ConfDir/$RemoteMD5File' for writing: $!.");
			return 1;
		}
		print MD5_FILE $conf_md5;
		close (MD5_FILE);
		copy ("$ConfDir/$ConfFile", "$Conf{'temporal'}/$RemoteConfFile");
		send_file ("$Conf{'temporal'}/$RemoteConfFile");
		send_file ("$Conf{'temporal'}/$RemoteMD5File");
		log_message ('remote config', 'Uploading configuration for the first time.');
		unlink ("$Conf{'temporal'}/$RemoteConfFile");
		unlink ("$Conf{'temporal'}/$RemoteMD5File");
		return 0;
	}

	if (! open (MD5_FILE, "< $Conf{'temporal'}/$RemoteMD5File")) {
		error ("Could not open file '$ConfDir/$RemoteMD5File' for writing: $!.");
		return 1;
	}
	
	my $remote_conf_md5 = <MD5_FILE>;
	close (MD5_FILE);
	
	# No changes
	return 0 if ($remote_conf_md5 eq $conf_md5);
	
	# Get the new configuration file
	return 1 if (recv_file ($RemoteConfFile) != 0);
	log_message ('remote config', 'Configuration has changed!');

	# Empty modules, plugins and collections
	@Modules = ();
	@Plugins = ();
	%Collections = ();

	# Save the new configuration and reload it
	move ("$Conf{'temporal'}/$RemoteConfFile", "$ConfDir/$ConfFile");
	read_config ();
	
	# Log file may have changed
	stop_log ();
	start_log ('quiet');
	
	#Set nice of the pandora_agent
	my $PID = $$;
	`renice "$Conf{'pandora_nice'}" "$PID"`;
	
	return 0;
}

################################################################################
# Launchs tentacle server in proxy mode.
################################################################################
sub launch_tentacle_proxy () {

	# Check if proxy server ip is right.
	if ($Conf{'server_ip'} ne "localhost") {	
		
		#Create a new process and launch tentacle.
		$tentacle_pid = fork();	

		if ($tentacle_pid == 0) {

			#Execute tentacle server as a daemon
			my $new_process = "tentacle_server -b ".$Conf{'server_ip'}." -g ".$Conf{'server_port'}." -c ".$Conf{'proxy_max_connection'}." -t ".$Conf{'proxy_timeout'};

			log_message ('setup', 'Proxy mode enabled');
			exec ($new_process);		
		} 
	} else {
		error ('You can not proxy to localhost');
		return 1;
	}
	
	return 0;
}

################################################################################
# Delete old collections and download new collections.
################################################################################
sub check_collections () {

	# Delete old collections
	opendir (DIR, "$ConfDir/collections") || return;
 	while (defined (my $file_name = readdir(DIR))) {
		next if ($file_name eq '.' || $file_name eq '..');

		# Do not delete md5 files associated to a collection
		$file_name =~ s/\.md5$//;

		if (! defined ($Collections{$file_name})) {
			rmrf ("$ConfDir/collections/$file_name");
			unlink ("$ConfDir/collections/$file_name.md5");
		}
	}
	closedir (DIR);

	# Download new collections
	while (my ($collection, $in_path) = each (%Collections)) {
		my $collection_file = $collection . ".zip";
		my $collection_md5_file = $collection . ".md5";

		# Add the collection directory to the PATH
		if ($in_path == 0) {
			$Collections{$collection} = 1;
			add_dir_to_path ("$ConfDir/collections/$collection");
		}

		# Get remote md5
 		if (-l "$Conf{'temporal'}/$collection_md5_file" && !unlink("$Conf{'temporal'}/$collection_md5_file")) {
			error ("File '$Conf{'temporal'}/$collection_md5_file' already exists as a symlink and could not be removed: $!.");
			return 1;
		}
		
		next unless (recv_file ($collection_md5_file) == 0);
		if (! open (MD5_FILE, "< $Conf{'temporal'}/$collection_md5_file")) {
			error ("Could not open file '$Conf{'temporal'}/$collection_md5_file' for reading: $!.");
			return 2;
		}
		
		my $remote_collection_md5 = <MD5_FILE>;
		close (MD5_FILE);
		unlink ("$Conf{'temporal'}/$collection_md5_file");

		# Read local md5
		my $local_collection_md5 = '';
		if (defined (open (MD5_FILE, "< $ConfDir/collections/$collection_md5_file"))) {
			$local_collection_md5 = <MD5_FILE>;
			close MD5_FILE;
		}

		# Check for changes
		$local_collection_md5 = $remote_collection_md5 unless defined ($local_collection_md5);
		next if ($local_collection_md5 eq $remote_collection_md5);
		
		# Download and unzip
		next unless (recv_file ($collection_file) == 0);
		rmrf ("$ConfDir/collections/$collection");
		`unzip -d "$ConfDir/collections/$collection" "$Conf{'temporal'}/$collection_file" 2>$DevNull`;
		unlink ("$Conf{'temporal'}/$collection_file");		
		
		# Save the new md5
		if (! open (MD5_FILE, "> $ConfDir/collections/$collection_md5_file")) {
			error ("Could not open file '$ConfDir/collections/$collection_md5_file' for writing: $!.");
			return 2;
		}
		
		print MD5_FILE "$remote_collection_md5";
		close (MD5_FILE);
		
		# Set proper file permissions
		chmodr (0750, "$ConfDir/collections/$collection");
	}
}

###############################################################################
# MD5 leftrotate function. See http://en.wikipedia.org/wiki/MD5#Pseudocode.
###############################################################################
sub leftrotate ($$) {
	my ($x, $c) = @_;

	return (0xFFFFFFFF & ($x << $c)) | ($x >> (32 - $c));
}

###############################################################################
# Initialize some variables needed by the MD5 algorithm.
# See http://en.wikipedia.org/wiki/MD5#Pseudocode.
###############################################################################
my (@R, @K);
sub md5_init () {

	# R specifies the per-round shift amounts
	@R = (7, 12, 17, 22,  7, 12, 17, 22,  7, 12, 17, 22,  7, 12, 17, 22,
		  5,  9, 14, 20,  5,  9, 14, 20,  5,  9, 14, 20,  5,  9, 14, 20,
		  4, 11, 16, 23,  4, 11, 16, 23,  4, 11, 16, 23,  4, 11, 16, 23,
		  6, 10, 15, 21,  6, 10, 15, 21,  6, 10, 15, 21,  6, 10, 15, 21);

	# Use binary integer part of the sines of integers (radians) as constants
	for (my $i = 0; $i < 64; $i++) {
		$K[$i] = floor(abs(sin($i + 1)) * MOD232);
	}
}

###############################################################################
# Return the MD5 checksum of the given string. 
# Pseudocode from http://en.wikipedia.org/wiki/MD5#Pseudocode.
###############################################################################
sub md5 ($) {
	my $str = shift;

	# Note: All variables are unsigned 32 bits and wrap modulo 2^32 when calculating

	# Initialize variables
	my $h0 = 0x67452301;
	my $h1 = 0xEFCDAB89;
	my $h2 = 0x98BADCFE;
	my $h3 = 0x10325476;

	# Pre-processing
	my $msg = unpack ("B*", pack ("A*", $str));
	my $bit_len = length ($msg);

	# Append "1" bit to message
	$msg .= '1';

	# Append "0" bits until message length in bits ≡ 448 (mod 512)
	$msg .= '0' while ((length ($msg) % 512) != 448);

	# Append bit /* bit, not byte */ length of unpadded message as 64-bit little-endian integer to message
	$msg .= unpack ("B64", pack ("VV", $bit_len));

	# Process the message in successive 512-bit chunks
	for (my $i = 0; $i < length ($msg); $i += 512) {

		my @w;
		my $chunk = substr ($msg, $i, 512);

		# Break chunk into sixteen 32-bit little-endian words w[i], 0 <= i <= 15
		for (my $j = 0; $j < length ($chunk); $j += 32) {
			push (@w, unpack ("V", pack ("B32", substr ($chunk, $j, 32))));
		}

		# Initialize hash value for this chunk
		my $a = $h0;
		my $b = $h1;
		my $c = $h2;
		my $d = $h3;
		my $f;
		my $g;

		# Main loop
		for (my $y = 0; $y < 64; $y++) {
			if ($y <= 15) {
				$f = $d ^ ($b & ($c ^ $d));
				$g = $y;
			}
			elsif ($y <= 31) {
				$f = $c ^ ($d & ($b ^ $c));
				$g = (5 * $y + 1) % 16;
			}
			elsif ($y <= 47) {
				$f = $b ^ $c ^ $d;
				$g = (3 * $y + 5) % 16;
			}
			else {
				$f = $c ^ ($b | (0xFFFFFFFF & (~ $d)));
				$g = (7 * $y) % 16;
			}

			my $temp = $d;
			$d = $c;
			$c = $b;
			$b = ($b + leftrotate (($a + $f + $K[$y] + $w[$g]) % MOD232, $R[$y])) % MOD232;
			$a = $temp;
		}

		# Add this chunk's hash to result so far
		$h0 = ($h0 + $a) % MOD232;
		$h1 = ($h1 + $b) % MOD232;
		$h2 = ($h2 + $c) % MOD232;
		$h3 = ($h3 + $d) % MOD232;
	}

	# Digest := h0 append h1 append h2 append h3 #(expressed as little-endian)
	return unpack ("H*", pack ("V", $h0)) . unpack ("H*", pack ("V", $h1)) . unpack ("H*", pack ("V", $h2)) . unpack ("H*", pack ("V", $h3));
}

################################################################################
# Try to guess the OS version.
################################################################################
sub guess_os_version {
	my $os = shift;
	my $os_version;

	# Linux
	if ($os eq 'linux') {
		$os_version = `cat /etc/*ease|grep PRETTY| cut -f 2 -d= | tr -d '"' 2>$DevNull`;
	# AIX
	} elsif ($os eq 'aix') {
		$os_version = "$2.$1" if (`uname -rv` =~ /\s*(\d)\s+(\d)\s*/);
	# Windows
	} elsif ($os =~ /win/i) {
		$os_version = `ver`;
		$DevNull = '/Nul';
		$CmdSep = '\&';
		$OS = "windows";

	# Solaris, HP-UX, BSD and others
	} else {
		$os_version = `uname -r`;
	}
	
	# Something went wrong
	return '' unless defined ($os_version);
	
	# Remove any trailing new lines
	chomp ($os_version);

	return $os_version;
}

################################################################################
# Execute the given module.
################################################################################
sub exec_module ($) {
	my $module = shift;

	# Need something to execute
	if ($module->{'func'} == 0) {
		$ThreadSem->up () if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1);
		return;
	}
	
	# Check module interval
	if (++($module->{'counter'}) < $module->{'intensive_interval'}) {
		$ThreadSem->up () if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1);
		return;
	}

	# Check module cron
	if (check_module_cron ($module) != 1) {
		$ThreadSem->up () if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1);
		return;
	}

	# Check module preconditions
	if (evaluate_module_preconditions ($module) == 0) {
		return;
	}
	
	# Reset module counter
	$module->{'counter'} = 0;

	# Temporarily disable strict refs
	no strict 'refs';

	# Run
	my @value = &{$module->{'func'}}($module);
	if (defined ($value[0])) {

		# Evaluate intensive conditions
		if ($module->{'is_intensive'} == 1) {
			my $intensive_match = evaluate_module_intensive_conditions ($module, $value[0]);
			if ($intensive_match == $module->{'intensive_match'} && $module->{'timestamp'} + $module->{'interval'} * $Conf{'interval'} > time ()) {
				$ThreadSem->up () if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1);
				return;
			}
			
			# Update the time reference
			$module->{'timestamp'} = time () if ($module->{'timestamp'} + $module->{'interval'} * $Conf{'interval'} <= time ());
			
			# Update the intensive match status
			$module->{'intensive_match'} = $intensive_match;
		}
		
		# Evaluate module conditions
		evaluate_module_conditions ($module, $value[0]);
		
		# Write the module XML
		write_module_xml ($module, @value);
	}
	
	# Save the module value if needed (only works for the first returned value)
	if ($module->{'save'} ne '') {
		if (defined ($value[0])) {
			$ENV{$module->{'save'}} = $value[0] ;
		} else {
			$ENV{$module->{'save'}} = '';
		}
	}
	
	$ThreadSem->up () if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1);
}

################################################################################
# Load process information.
################################################################################
sub load_procs () {
	my $utimestamp = time ();

	# Do we know hoy to get process information in this OS?
	return unless defined (PROC_CMDS->{$OS});

	# Update at most once every interval
	return if ($Procs{'__utimestamp__'} > ($utimestamp - $Conf{'interval'}));

	# Get process information
	my $cmd = PROC_CMDS->{$OS};
	my @procs = `$cmd`;
	return undef unless ($? eq 0);

	# Clear past process infomation
	%Procs = ();

	# Parse process information
	foreach my $proc (@procs) {

		chomp ($proc);		
		my @proc_info = split (/\s+/, $proc);
		next unless ($#proc_info >= 2);

		# Process command
		my $proc_cmd = join (' ', @proc_info[2..$#proc_info]);

		# Process command
		$Procs{$proc_cmd} = ();
		
		# Process CPU usage
		$Procs{$proc_cmd}{'cpu'} = $proc_info[0];

		# Process virtual size
		$Procs{$proc_cmd}{'size'} = $proc_info[1];
	}

	$Procs{'__utimestamp__'} = $utimestamp;
}

################################################################################
# Load partition information.
################################################################################
sub load_parts () {
	my $utimestamp = time ();

	# Do we know hoy to get partition information in this OS?
	return unless defined (PART_CMDS->{$OS});

	# Update at most once every interval
	return if ($Parts{'__utimestamp__'} > ($utimestamp - $Conf{'interval'}));

	# Get partition information
	my $cmd = PART_CMDS->{$OS};
	my @parts = `$cmd`;
	return undef unless ($? eq 0);

	# Parse partition information
	foreach my $part (@parts) {

		chomp ($part);		
		my @part_info = split (/\s+/, $part);
		next unless ($#part_info >= 2);
		
		my $part = join (' ', @part_info[2..$#part_info]);

		# Mount point
		$Parts{$part} = ();
		
		# Total space in kB
		$Parts{$part}{'total'} = $part_info[0];

		# Available space in kB
		$Parts{$part}{'avail'} = $part_info[1];
	}

	$Parts{'__utimestamp__'} = $utimestamp;
}

################################################################################
# Execute the given command.
################################################################################
sub module_exec ($) {
	my $module = shift;
	my @data;
	my $exe;

	# Check module parameters
	return () unless ($module->{'params'} ne '');

	# Execute the command
	if ($module->{'timeout'} == 0) {
		@data = `$module->{'params'} 2> $DevNull`;
	} else {
		my $cmd = quotemeta ($module->{'params'});
		@data = `$Conf{'pandora_exec'} $module->{'timeout'} $cmd 2> $DevNull`;
	}

	# Something went wrong or no data
	return () unless ($? eq 0 && defined ($data[0]));

	return @data;
}

################################################################################
# Get the status of a process. 1 running, 0 not running.
################################################################################
sub module_proc ($) {
	my $module = shift;
	
	# Check module parameters
	return () unless ($module->{'params'} ne '');

	# Win32
	if ($OS eq 'windows') {
		return ($Win32->get_process_status($module->{'params'}));
	}

	# Data collection layer
	load_procs ();

	return (1) if defined ($Procs{$module->{'params'}});
	return (0);
}

################################################################################
# Get the status of a service. 1 running, 0 not running.
################################################################################
sub module_service ($) {
	my $module = shift;
	
	# Check module parameters
	return () unless ($module->{'params'} ne '');

	# Win32
	if ($OS eq 'windows') {
		return ($Win32->get_service_status($module->{'params'}));
	}

	return (module_proc($module));
}

################################################################################
# Get the CPU usage of a process.
################################################################################
sub module_cpuproc ($) {
	my $module = shift;

	# Check module parameters
	return () unless ($module->{'params'} ne '');

	# Data collection layer
	load_procs ();

	return () unless defined ($Procs{$module->{'params'}}) and defined ($Procs{$module->{'params'}}{'cpu'});
	return ($Procs{$module->{'params'}}{'cpu'});
}

################################################################################
# Get the memory usage of a process in Mbytes.
################################################################################
sub module_memproc ($) {
	my $module = shift;

	# Check module parameters
	return () unless ($module->{'params'} ne '');

	# Data collection layer
	load_procs ();

	return () unless defined ($Procs{$module->{'params'}}) and defined ($Procs{$module->{'params'}}{'size'});
	return (sprintf ("%d", $Procs{$module->{'params'}}{'size'} / 1024));
}

################################################################################
# Get the free space in a partition in Mbytes.
################################################################################
sub module_freedisk ($) {
	my $module = shift;

	# Check module parameters
	return () unless ($module->{'params'} ne '');

	# Win32
	if ($OS eq 'windows') {
		return ($Win32->get_free_disk_space($module->{'params'}));
	}
	
	# Data collection layer
	load_parts ();

	return () unless defined ($Parts{$module->{'params'}}) and defined ($Parts{$module->{'params'}}{'avail'});
	
	my $avail = sprintf("%d", $Parts{$module->{'params'}}{'avail'} / 1024);
	return ($avail);
}

################################################################################
# Get the free space in a partition in %.
################################################################################
sub module_freepercentdisk ($) {
	my $module = shift;

	# Check module parameters
	return () unless ($module->{'params'} ne '');

	# Win32
	if ($OS eq 'windows') {
		return ($Win32->get_free_disk_space_percentage($module->{'params'}));
	}
	
	# Data collection layer
	load_parts ();

	return () unless defined ($Parts{$module->{'params'}}) and defined ($Parts{$module->{'params'}}{'avail'});
	
	my $availp = sprintf("%d", $Parts{$module->{'params'}}{'avail'} * 100 / $Parts{$module->{'params'}}{'total'});
	return ($availp);
}

################################################################################
# Get the occupied space in a partition in %.
################################################################################
sub module_occupiedpercentdisk ($) {
	my $module = shift;

	# Check module parameters
	return () unless ($module->{'params'} ne '');

	# Data collection layer
	load_parts ();

	return () unless defined ($Parts{$module->{'params'}}) and defined ($Parts{$module->{'params'}}{'avail'});
	
	my $occupiedp = sprintf("%d", ($Parts{$module->{'params'}}{'total'} - $Parts{$module->{'params'}}{'avail'}) * 100 / $Parts{$module->{'params'}}{'total'});
	return ($occupiedp);
}

################################################################################
# Get the CPU usage %.
################################################################################
sub module_cpuusage ($) {
	my $module = shift;

	# Win32
	if ($OS eq 'windows') {
		return ($Win32->get_cpu_usage());
	}
	
	# Do we know hoy to get CPU usage in this OS?
	return () unless defined (CPUUSAGE_CMDS->{$OS});

	# Get CPU usage
	my $cmd = CPUUSAGE_CMDS->{$OS};
	my @data = `$cmd 2> $DevNull`;

	# Something went wrong or no data
	return () unless ($? eq 0 && defined ($data[0]));

	return ($data[0]);
}

################################################################################
# Get the free space in a partition in Mbytes.
################################################################################
sub module_freememory ($) {
	my $module = shift;
	
	# Win32
	if ($OS eq 'windows') {
		return ($Win32->get_free_memory());
	}
	
	# Do we know hoy to get memory information in this OS?
	return () unless defined (FREEMEMORY_CMDS->{$OS});

	# Get available memory
	my $cmd = FREEMEMORY_CMDS->{$OS};
	my @data = `$cmd 2> $DevNull`;

	# Something went wrong or no data
	return () unless ($? eq 0 && defined ($data[0]));

	return (sprintf ("%d", $data[0] / 1024));
}

################################################################################
# Get the free space in a partition in %.
################################################################################
sub module_freepercentmemory ($) {
	my $module = shift;
	
	# Win32
	if ($OS eq 'windows') {
		return ($Win32->get_free_memory_percentage());
	}
	
	# Do we know hoy to get memory information in this OS?
	return unless defined (TOTALMEMORY_CMDS->{$OS});

	# Get CPU usage
	my $cmd = TOTALMEMORY_CMDS->{$OS};
	my @data = `$cmd 2> $DevNull`;

	# Something went wrong or no data
	return () unless ($? eq 0 && defined ($data[0]));

	# Get total memory in MB
	my $total = sprintf ("%d", $data[0] / 1024);
	
	# Get available memory in MB
	my ($avail) = module_freememory ($module);
	return () unless defined ($avail);
	
	return sprintf (("%d", $avail * 100 / $total));
}

################################################################################
# Evaluate and execute module preconditions.
################################################################################
sub evaluate_module_preconditions ($) {
	my ($module) = @_;

	# Evaluate preconditions
	foreach my $precondition (@{$module->{'precondition'}}) {
		my $data = `$precondition->{'command'} 2> $DevNull`;		
		return 0 if (evaluate_condition ($precondition, $data) == 0);
	}

	return 1;
}

################################################################################
# Evaluate a module condition. Returns 1 if the condition matches, 0 otherwise.
################################################################################
sub evaluate_condition ($$) {
	my ($condition, $data) = @_;
	
	{
		no warnings;
		if (($condition->{'operator'} eq '>' && $data > $condition->{'value_1'}) ||
			($condition->{'operator'} eq '<' && $data < $condition->{'value_1'}) ||
			($condition->{'operator'} eq '=' && $data == $condition->{'value_1'}) ||
			($condition->{'operator'} eq '!=' && $data != $condition->{'value_1'}) ||
			($condition->{'operator'} eq '=~' && $data =~ /$condition->{'value_1'}/) ||
			($condition->{'operator'} eq '()' && $data > $condition->{'value_1'} && $data < $condition->{'value_2'})) {
				return 1;
		}
	}
	
	return 0;
}


################################################################################
# Evaluate and execute module conditions.
################################################################################
sub evaluate_module_conditions ($$) {
	my ($module, $data) = @_;

	# Evaluate conditions
	foreach my $condition (@{$module->{'conditions'}}) {
		if (evaluate_condition ($condition, $data) == 1) {
				`$condition->{'command'} 2> $DevNull`;
		}
	}
}

################################################################################
# Evaluate intensive conditions.
################################################################################
sub evaluate_module_intensive_conditions ($$) {
	my ($module, $data) = @_;

	# Evaluate conditions
	foreach my $condition (@{$module->{'intensive_conditions'}}) {
		return 0 if (evaluate_condition ($condition, $data) == 0);
	}
	
	return 1;
}

################################################################################
# Checks the module's cron string. Returns 1 if the module should be run, 0 if
# not.
################################################################################
sub check_module_cron ($) {
	my $module = shift;
	
	# No cron string defined
	return 1 unless ($module->{'cron'} ne '');

	# Check if the module was already executed
	return 0 unless (time() > $module->{'cron_utimestamp'});

	# Get cron configuration
	my @cron_params = split (/\s/, $module->{'cron'});

	# Get current time
	my $current_time = time();
	my @time = localtime($current_time);

	# Minutes, hours, day of the month, month and day of the week
	my @time_params = @time[1, 2, 3, 4, 6];

	# Fix month (localtime retuns 0..11 and we need 1..12)
	$time_params[3] += 1;
	
	# Check cron parameters	
	for (my $i = 0; $i < 5; $i++) {
		
		# Wildcard
		next if ($cron_params[$i] eq '*');
		
		# Get interval
		my ($bottom, $top) = split (/-/, $cron_params[$i]);
		$top = $bottom unless defined ($top);
		
		# Check interval
		if ($bottom <= $top) {
			return 0 if ($time_params[$i] < $bottom || $time_params[$i] > $top);
		} else {
			return 0 if ($time_params[$i] < $bottom && $time_params[$i] > $top);
		}
	}

	# Do not check in the next minute, hour, day or month.
	my $offset = 0; 
	if ($module->{'cron_interval'} >= 0) {
		$offset = $module->{'cron_interval'};
	} elsif($cron_params[0] ne '*') {
		# 1 minute
		$offset = 60;
	} elsif($cron_params[1] ne '*') {
		# 1 hour
		$offset = 3600;
	} elsif($cron_params[2] ne '*' || $cron_params[4] ne '*') {
		# 1 day
		$offset = 86400;
	} elsif($cron_params[3] ne '*') {
		# 31 days
		$offset = 2678400;
	}

	$module->{'cron_utimestamp'} = $current_time + $offset;
	return 1;
}

################################################################################
# Write module data in XML format.
################################################################################
sub write_module_xml ($@) {
	my ($module, @data) = @_;

	# No data
	return unless (defined $data[0]);

	# Critical section
	$Sem->down () if (defined ($Sem));

	$Xml .= "	<module>\n" .
		"	<name><![CDATA[" . $module->{'name'} . "]]></name>\n" .
		"	<description><![CDATA[" . $module->{'description'} . "]]></description>\n" . 
		"	<type>" . $module->{'type'} . "</type>\n";

	# Interval
	$Xml .= "	<module_interval>" . $module->{'interval'} . "</module_interval>\n";
	
	# Min
	$Xml .= "	<min>" . $module->{'min'} . "</min>\n" if (defined ($module->{'min'}));

	# Max
	$Xml .= "	<max>" . $module->{'max'} . "</max>\n" if (defined ($module->{'max'}));

	# Post process
	$Xml .= "	<post_process>" . $module->{'post_process'} . "</post_process>\n" if (defined ($module->{'post_process'}));

	# Min critical
	$Xml .= "	<min_critical>" . $module->{'min_critical'} . "</min_critical>\n" if (defined ($module->{'min_critical'}));

	# Max critical
	$Xml .= "	<max_critical>" . $module->{'max_critical'} . "</max_critical>\n" if (defined ($module->{'max_critical'}));

	# Min warning
	$Xml .= "	<min_warning>" . $module->{'min_warning'} . "</min_warning>\n" if (defined ($module->{'min_warning'}));

	# Max warning
	$Xml .= "	<max_warning>" . $module->{'max_warning'} . "</max_warning>\n" if (defined ($module->{'max_warning'}));

	# Disabled
	$Xml .= "	<disabled>" . $module->{'disabled'} . "</disabled>\n" if (defined ($module->{'disabled'}));

	# Min ff event
	$Xml .= "	<min_ff_event>" . $module->{'min_ff_event'} . "</min_ff_event>\n" if (defined ($module->{'min_ff_event'}));

	# Data list
	if ($#data > 0) {
		$Xml .= "	<datalist>\n";
		foreach my $data_item (@data) {
			chomp ($data_item);
			$Xml .= "	<data><value><![CDATA[$data_item]]></value></data>\n";
		}
		$Xml .= "	</datalist>\n";
	# Single data
	} else {
		chomp ($data[0]);
		$Xml .= "	<data><![CDATA[$data[0]]]></data>\n";
	}
	$Xml .= "	</module>\n";

 	$Sem->up () if (defined ($Sem));
}

################################################################################
# Receive a UDP server signal to restart agent
################################################################################
sub udp_server_signal () {
	log_message ('udp server', 'Received signal to restart the agent.');
}

################################################################################
# Basic UDP server to restart agent on UDP signal received
################################################################################
sub udp_server ($$) {

	my $udp_port = shift;
	my $udp_auth_address = shift;
	my $parent_pid = getppid();

	my($sock, $oldmsg, $newmsg, $hisaddr, $hishost, $MAXLEN);
	$MAXLEN = 1024;

	log_message ('udp server', 'Starting UDP server listening on '.$udp_auth_address.":".$udp_port);
	$sock = IO::Socket::INET->new(LocalPort => $udp_port, Proto => 'udp') or die "socket: $@";

	while ($sock->recv($newmsg, $MAXLEN)) {
		my($port, $ipaddr) = sockaddr_in($sock->peername);
		$hishost = gethostbyaddr($ipaddr, AF_INET);

		log_message ('udp server', 'Received signal from '.$hishost);

		if (($udp_auth_address eq "0.0.0.0") || ($hishost eq $udp_auth_address)){
			if ($newmsg =~ /REFRESH AGENT/){
				# Send signal to restart agent
				kill 'SIGINT' , $parent_pid;
			}
		}
	}
}

################################################################################
# Execute the given plugin.
################################################################################
sub exec_plugin ($) {
	my $plugin = shift;

	my $output = `$plugin 2>$DevNull`;

	# Do not save the output if there was an error
	if ($? != 0) {
		$ThreadSem->up () if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1);
		return;
	}

	# Critical section
	$Sem->down () if (defined ($Sem));
	$Xml .= $output;
 	$Sem->up () if (defined ($Sem));

	$ThreadSem->up () if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1);
}

################################################################################
# TERM Handler
################################################################################
sub kill_signal_handler (){
	# Kill tentacle server if it was launched

	if (defined ($tentacle_pid)) {
			print "kill -9 $tentacle_pid\n";
			`kill -9 $tentacle_pid`;
	}
	exit (0);
}

################################################################################
# Get the free disk space in the temporal directory (in bytes).
################################################################################
sub temporal_freedisk () {

	# Call df
	return 0 unless defined (DF_CMDS->{$OS});
	my $cmd = DF_CMDS->{$OS} . ' ' . $Conf{'temporal'} . ' | awk \'NR > 1 {print $4}\'';	
	my $temporal_freedisk = `$cmd`;

	# Check for errors
	return 0 unless ($? eq 0);

	# Convert to bytes
	return 1024 * int ($temporal_freedisk);
}

################################################################################
# Launches one execution ot the Pandora FMS agent.
# Returns 1 if the agent should execute again, 0 if not.
################################################################################
sub pandora_agent_run () {

	# Must be set to 0 if the agent is a broker agent
	my $main_agent = -1;

	# Ignore signals from UDP and Tentacle server while processing execution
	if ($Conf{'udp_server'} == 1 || $Conf{'proxy_mode'}){
		$SIG{'INT'} = 'DEFAULT';
	}

	# Check for a new configuration
	check_remote_config () unless ($Conf{'debug'} eq '1');

	# Check file collections
	check_collections () unless ($Conf{'debug'} eq '1');

	# Launch broker agents
	@BrokerPid = ();
	my @broker_agents = read_config ('broker_agent');
	foreach my $broker_agent (@broker_agents) {
		
		# Create broker conf file if it does not exist
		if (! -e "$ConfDir/${broker_agent}.conf") {
			write_broker_conf($broker_agent);
		}
		
		$main_agent = fork ();
			
		# Broker agent
		if ($main_agent == 0) {
		
			# Set the configuration file
			$ConfFile = "${broker_agent}.conf";
			
			# Log to a new file
			stop_log ();
			start_log ('quiet');
				
			# Read configuration file
			@Modules = ();
			@Plugins = ();
			%Collections = ();
			read_config ();
					
			# Check for a new configuration
			check_remote_config () unless ($Conf{'debug'} eq '1');
				
			# Check file collections
			check_collections () unless ($Conf{'debug'} eq '1');
					
			# Execute
			last;
		} else {
			push (@BrokerPid, $main_agent);
		}
	}

	my $address;

	if(defined($Conf{'address'})) {
		# Check if address is auto to get the local ip
		if ($Conf{'address'} eq 'auto') {
			# Tested on Ubuntu, debian, Suse, Solaris 10 and AIX 5.1
			$address = `ifconfig -a | grep -v '127.0.0' | grep '[0-9]*\\.[0-9]*\\.[0-9]*' | awk '{ print \$2 }' | head -1 | sed -e 's/addr\\://' | sed -e 's/inet\\://'`;
			chomp($address);
		}
		else {
			$address = $Conf{'address'};
		}
	}
	
	# Clear the XML
	$Xml = "";

	# Execute modules
	foreach my $module (@Modules) {

		# Execute the module in a separate thread
		if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1) {
			$ThreadSem->down ();
			my $thr = threads->create (\&exec_module, $module);
			if (! defined ($thr)) {
				$ThreadSem->up ();
			} else {
				$thr->detach();
			}
		# Execute the module
		} else {
			exec_module ($module);
		}
	}

	# Execute plugins
	if ($Conf{'timestamp'} + $Conf{'interval'} <= time ()) {
		foreach my $plugin (@Plugins) {
	
			# Execute the plugin in a separate thread
			if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1) {
				$ThreadSem->down ();
				my $thr = threads->create (\&exec_plugin, $plugin);
				if (! defined ($thr)) {
					$ThreadSem->up ();
				} else {
					$thr->detach();
				}
			# Execute the plugin
			} else {
				exec_plugin ($plugin);
			}
		}
	}

	# Wait for all the threads
	$ThreadSem->down ($Conf{'agent_threads'}) if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1);
	$ThreadSem->up ($Conf{'agent_threads'}) if (defined ($ThreadSem) && $Conf{'agent_threads'} > 1);

	if ($Xml ne "" || $Conf{'timestamp'} + $Conf{'interval'} <= time ()) {
		
		# Update the time reference
		$Conf{'timestamp'} = time () if ($Conf{'timestamp'} + $Conf{'interval'} <= time ());
		
		# Compose the XML
		my $xml_header = "<?xml version='1.0' encoding='" . $Conf{'encoding'} . "'?>\n" .
			"<agent_data description='" . $Conf{'description'} ."' group='" . $Conf{'group'} .
			"' os_name='$OS' os_version='$OS_VERSION' interval='" . $Conf{'interval'} .
			"' version='" . AGENT_VERSION . '(Build ' . AGENT_BUILD . ')' . ($Conf{'autotime'} eq '1' ? '' : "' timestamp='" . strftime ('%Y/%m/%d %H:%M:%S', localtime ())) .
			"' agent_name='" . $Conf{'agent_name'} . "' timezone_offset='". $Conf{'timezone_offset'}; 
	
		if (defined ($Conf{'address'})) {
			$xml_header .= "' address='" .$address;
		}
		
		if (defined ($Conf{'parent_agent_name'})) {
			$xml_header .= "' parent_agent_name='" .$Conf{'parent_agent_name'};
		}
		
		# Check the gis mode (exec or manual). If exec script is defined, we execute it and get the coordenates
		if (defined ($Conf{'gis_exec'}) && (-e $Conf{'gis_exec'})) {		
			my $coord_str = `$Conf{'gis_exec'}`;
			chomp($coord_str);
			my @coords = split(',',$coord_str);
			# Check if lat and long are numeric
			if (defined($coords[0]) && defined($coords[1]) && ($coords[0] =~ /^-?(\d+)\.(\d+)$|^-?(\d+)$/) && ($coords[1] =~ /^-?(\d+)\.(\d+)$|^-?(\d+)$/)) {
				my $lat = $coords[0];
				my $long = $coords[1];
				
				$xml_header .= "' longitude='" .$long . "' latitude='" .$lat;
	
				if (defined ($coords[2])) {
					my $alt = $coords[2];
					$xml_header .= "' altitude='" .$alt;
				}
				if (defined ($Conf{'position_description'})) {
					$xml_header .= "' position_description='" .$Conf{'position_description'};
				}
			}
		}
		elsif (defined ($Conf{'longitude'}) && defined ($Conf{'latitude'})) {
			$xml_header .= "' longitude='" .$Conf{'longitude'} . "' latitude='" .$Conf{'latitude'};
			if (defined ($Conf{'altitude'})) {
				$xml_header .= "' altitude='" .$Conf{'altitude'};
			}
			if (defined ($Conf{'position_description'})) {
				$xml_header .= "' position_description='" .$Conf{'position_description'};
			}
		}
		$xml_header .= "'>\n";
		$Xml = $xml_header . $Xml . "</agent_data>";

		# Save XML data file
		my $temp_file = $Conf{'temporal'} . '/' . $Conf{'agent_name'} . '.' . time () . '.data';
		if (-l $temp_file && !unlink($temp_file)) {
			error ("File '$temp_file' already exists as a symlink and could not be removed: $!");
			return 1;
		}
		
		if (! open (TEMP_FILE, "> $temp_file")) {
			error ("Could not write XML data file: $!");
			return 1;
		}
		
		print TEMP_FILE $Xml;
		close (TEMP_FILE);

		# Debug mode
		if ($Conf{'debug'} eq '1') {
			log_message ('debug', "Wrote XML data file '$temp_file'");
			log_message ('debug', "Wrote XML data file '$temp_file'", *STDOUT);
			return 0;
		}

		# Send the XML data file
		my $rc = send_file ($temp_file, 1);
		if ($rc == 0 || $Conf{'xml_buffer'} == 0 || temporal_freedisk () < $Conf{'temporal_min_size'}) {
			unlink ($temp_file);
		}
		
		# Send buffered XML data files
		if ($Conf{'xml_buffer'} == 1) {
			send_buffered_xml_files ();
		}
	}
	
	# Enable signal capture to break the Sleep interval on UDP signal
	if ($Conf{'udp_server'} == 1) {
		$SIG{'INT'} = \&udp_server_signal;
	}

	# Sleep if main agent
	if ($main_agent != 0) {
		foreach my $broker_pid (@BrokerPid) {
			waitpid ($broker_pid, 0);
		}
		
		# Cron mode
		return (0) if ($Conf{'cron_mode'} == 1);
	}
	# Finish if broker agent
	else {
		return (0);
	}
	
	return 1;
}

################################################################################
# Service run. The Startup() function is called automatically when the service
# starts.
################################################################################
sub Startup {

	# Configure the agent
	if (configure($Config{'Parameters'}) != 0) {
		return;
	}

	# Main agent loop
	do {
		if (pandora_agent_run () == 0) {
			return;
		}
	} while (ContinueRun($Conf{'intensive_interval'}));
}

################################################################################
# Interactive run. The Interactive() function is called when PandoraAgent.exe is
# run from the commandline.
################################################################################
sub Interactive () {

	if ($#ARGV != 0) {
		print_usage ();
		return;
	}
	
	# Set the path to the configuration file
	$Config{'Parameters'} = $ARGV[0];
	
	# Run!
	Startup();
}

################################################################################
# Configure the agent.
# Returns 0 if the configuration file was properly read, 1 if not.
################################################################################
sub configure ($) {
	my $conf_dir = shift;
	
	#Handler TERM signal.
	$SIG{'TERM'} = \&kill_signal_handler;

	$ConfDir = fix_directory ($conf_dir);
	if (! -d "$ConfDir") {
		error ("Directory '$ConfDir' does not exist.");
		return 1;
	}
	
	# Add util dir to PATH in Win32
	if ($OS eq 'windows') {
		add_dir_to_path ("$ConfDir\\util");
	}

	#Pandora home path
	$ENV{'PANDORA_HOME'}=$ConfDir;

	# Get user to run as
	my $pandora_user = read_config ('pandora_user');
	if (defined ($pandora_user)) {
		# Change the EUID
		my $pandora_user_uid = getpwnam ($pandora_user);
		if (!defined ($pandora_user_uid)) {
			error ("Cannot get uid for user $pandora_user. Does the user exist and can we read /etc/passwd?");
			return 1;
		}
		$> = $pandora_user_uid;
		if ($> != $pandora_user_uid) {
			error ("Cannot run as $pandora_user: Insufficient permissions.");
			return 1;
		}
	}

	# Initialize MD5 variables
	md5_init ();

	# Start logging
	start_log ();

	log_message ('log', 'Running as user ' . getpwuid ($>)) if (defined (&getpwuid));

	# Read configuration file
	read_config ();

	$ENV{'PANDORA_AGENT'}=$Conf{'agent_name'};

	# Fix directory names
	$Conf{'temporal'} = fix_directory ($Conf{'temporal'});
	if (! -d "$Conf{'temporal'}") {
		error ("Temporal directory '" . $Conf{'temporal'} . "' does not exist.");
		return 1;
	}
	$Conf{'server_path'} = fix_directory ($Conf{'server_path'});
	$Conf{'secondary_server_path'} = fix_directory ($Conf{'secondary_server_path'});

	# Startup delay
	log_message ('log', 'Sleeping for ' . $Conf{'delayed_startup'} . ' seconds.') if 
	($Conf{'delayed_startup'} > 0);
	sleep ($Conf{'delayed_startup'});

	#Set nice of the pandora_agent
	if ($OS ne 'windows') {
		my $PID = $$;
		`renice "$Conf{'pandora_nice'}" "$PID"`;
	}

	#Launch tentacle server in proxy mode if configured
	if ($Conf{'proxy_mode'}) {
		
		#Check if user is root
		if ($> != 0) {		
			if (launch_tentacle_proxy() != 0) {
				return 1;
			}
		} else {
			error ('Proxy mode can not be launched as root');
			return 1;
		}
	}

	# Add the plugins directory to the PATH
	add_dir_to_path ("$ConfDir/plugins");

	# Start UDP server if configured
	if ($Conf{'udp_server'} == 1){
		my $pid = fork();

		if ($pid == 0){
			udp_server ($Conf{'udp_server_port'}, $Conf{'udp_server_auth_address'});
			return 1;
		}
	}
	
	return 0;
}

################################################################################
# Called before installing the service.
################################################################################
sub Install {
	if (defined ($ARGV[0])) {
		$Config{'Parameters'} = $ARGV[0];
	}
}

################################################################################
# Called before un-installing the service.
################################################################################
sub Remove {
}

################################################################################
# Main.
################################################################################

# Running as `perl pandora_agent`
if (! defined (&ContinueRun)) {

	if ($#ARGV != 0) {
		print_usage ();
		exit 1;
	}
	
	*ContinueRun = sub {
		if ($OS eq 'windows') {
			Win32::Sleep(1000*shift);
		} else {
			sleep ($Conf{'intensive_interval'});
		}
		return 1;
    };
	
	#*RunningAsService = sub {
	#	return 0;
	#};
	
	# Interactive run
	Interactive();
}

__END__

=head1 EXIT STATUS

=over 

=item 0 on Success

=item 1 on Error

=back 

=head1 CONFIGURATION

By default pandora_agent uses F</etc/pandora> as B<home configuration directory>. There is the F<pandora_agent.conf> file with all the configuration of the agent.

=head1 DEPENDENCIES


=head1 LICENSE

This is released under the GNU Lesser General Public License.

=head1 SEE ALSO


=head1 COPYRIGHT

Copyright (c) 2005-2010 Artica Soluciones Tecnologicas S.L

=cut