#!/usr/bin/perl
use strict;
my $VERSION = '0.2';
my $COPYRIGHT = 'Copyright (C) 2005-2011 Jonathan Buhacoff <jonathan@buhacoff.net>';
my $LICENSE = 'http://www.gnu.org/licenses/gpl.txt';
my %status = ( 'OK' => 0, 'WARNING' => 1, 'CRITICAL' => 2, 'UNKNOWN' => 3 );

#### IDEA AND INITIAL IMPLEMENTATION BASED ON CHECK_IMAP_RECEIVE WAS CONTRIBUTED BY JOHAN ROMME from THE NETHERLANDS 14 Oct 2011

# look for required modules
exit $status{UNKNOWN} unless load_modules(qw/Getopt::Long Mail::IMAPClient/);

BEGIN {
	if( grep { /^--hires$/ } @ARGV ) {
		eval "use Time::HiRes qw(time);";
		warn "Time::HiRes not installed\n" if $@;
	}
}

# get options from command line
Getopt::Long::Configure("bundling");
my $verbose = 0;
my $help = "";
my $help_usage = "";
my $show_version = "";
my $imap_server = "";
my $default_imap_port = "143";
my $default_imap_ssl_port = "993";
my $imap_port = "";
my $username = "";
my $password = "";
my $mailbox = "INBOX";
my $warntime = 15;
my $criticaltime = 30;
my $timeout = 60;
my $peek = "";
my $ssl = 0;
my $tls = 0;
my $time_hires = "";
my $ok;
$ok = Getopt::Long::GetOptions(
	"V|version"=>\$show_version,
	"v|verbose+"=>\$verbose,"h|help"=>\$help,"usage"=>\$help_usage,
	"w|warning=i"=>\$warntime,"c|critical=i"=>\$criticaltime,"t|timeout=i"=>\$timeout,
	# imap settings
	"H|hostname=s"=>\$imap_server,"p|port=i"=>\$imap_port,
	"U|username=s"=>\$username,"P|password=s"=>\$password, "m|mailbox=s"=>\$mailbox,
	"ssl!"=>\$ssl, "tls!"=>\$tls,
	# search settings
	"peek!"=>\$peek,
	# Time
	"hires"=>\$time_hires,
	);

if( $show_version ) {
	print "$VERSION\n";
	if( $verbose ) {
		print "Default warning threshold: $warntime seconds\n";
		print "Default critical threshold: $criticaltime seconds\n";
		print "Default timeout: $timeout seconds\n";
	}
	exit $status{UNKNOWN};
}

if( $help ) {
	exec "perldoc", $0 or print "Try `perldoc $0`\n";
	exit $status{UNKNOWN};
}

my @required_module = ();
push @required_module, 'IO::Socket::SSL' if $ssl || $tls;
exit $status{UNKNOWN} unless load_modules(@required_module);

if( $help_usage
	||
	( $imap_server eq "" || $username eq "" || $password eq "" )
  ) {
	print "Usage: $0 -H host [-p port] -U username -P password [--imap-retries <tries>]\n";
	exit $status{UNKNOWN};
}


# initialize
my $report = new PluginReport;
my $time_start = time;

# connect to IMAP server
print "connecting to server $imap_server\n" if $verbose > 2;
my $imap;
eval {
	local $SIG{ALRM} = sub { die "exceeded timeout $timeout seconds\n" }; # NB: \n required, see `perldoc -f alarm`
	alarm $timeout;
	
	if( $ssl || $tls ) {
		$imap_port = $default_imap_ssl_port unless $imap_port;		
		my $socket = IO::Socket::SSL->new("$imap_server:$imap_port");
		die IO::Socket::SSL::errstr() unless $socket;
		$socket->autoflush(1);
		$imap = Mail::IMAPClient->new(Socket=>$socket, Debug => 0 );
		$imap->State(Mail::IMAPClient->Connected);
		$imap->_read_line() if "$Mail::IMAPClient::VERSION" le "2.2.9"; # necessary to remove the server's "ready" line from the input buffer for old versions of Mail::IMAPClient. Using string comparison for the version check because the numeric didn't work on Darwin and for Mail::IMAPClient the next version is 2.3.0 and then 3.00 so string comparison works
		$imap->User($username);
		$imap->Password($password);
		$imap->login() or die "$@";
	}
	else {
		$imap_port = $default_imap_port unless $imap_port;		
		$imap = Mail::IMAPClient->new(Debug => 0 );		
		$imap->Server("$imap_server:$imap_port");
		$imap->User($username);
		$imap->Password($password);
		$imap->connect() or die "$@";
	}

	$imap->Peek(1) if $peek;
	$imap->Ignoresizeerrors(1);

	alarm 0;
};
if( $@ ) {
	chomp $@;
	print "IMAP QUOTA CRITICAL - Could not connect to $imap_server port $imap_port: $@\n";
	exit $status{CRITICAL};	
}
unless( $imap ) {
	print "IMAP QUOTA CRITICAL - Could not connect to $imap_server port $imap_port: $@\n";
	exit $status{CRITICAL};
}
my $time_connected = time;

my $quotaUsed;
my $quotaLimit;
my $quotaPercentage;
my $quotaPercentageWarning = 80;
my $quotaPercentageCritical = 90;
my $quotaMessage;

# look for the quota limits
my $tries = 0;
my @msgs;

eval {
	  my $k;
	  my @l = $imap->getquotaroot();
	  foreach $k (@l) {
		print "$k\n" if $verbose > 2;
		if ($k =~ /STORAGE +(\d+) +(\d+)/) {
		  $quotaUsed = $1;
		  $quotaLimit = $2;
		}
	  }
	  if (!length($quotaUsed) && !length($quotaLimit)) {
		print "no answer from imap host\n" if $verbose > 2;
	  } elsif (!length($quotaUsed) || !length($quotaLimit) {
		print "incorrect answer from imap host\n";
	$imap->close();
	exit $status{UNKNOWN};
	  } else {
		$quotaPercentage = sprintf("%.1f", (100 * $quotaUsed) / $quotaLimit);
		$quotaMessage = "$quotaUsed $quotaLimit - $quotaPercentage%";
	  }
};
if( $@ ) {
	chomp $@;
	print "IMAP QUOTA CRITICAL - Could not check quota at $imap_server port $imap_port: $@\n";
	exit $status{CRITICAL};	
}


# disconnect from IMAP server
print "disconnecting from server\n" if $verbose > 2;
$imap->logout();

# calculate elapsed time and issue warnings
my $time_end = time;
my $elapsedtime = $time_end - $time_start;
$report->{seconds} = $elapsedtime;

# print report and exit with known status

if($quotaPercentage >= $quotaPercentageCritical) {
	print "IMAP QUOTA CRITICAL - $quotaMessage\n";
	exit $status{CRITICAL};
}
if($quotaPercentage >= $quotaPercentageWarning) {
	print "IMAP QUOTA WARNING - $quotaMessage\n";
	exit $status{WARNING};
}
print "IMAP QUOTA OK - $quotaMessage\n";
exit $status{OK};


# utility to load required modules. exits if unable to load one or more of the modules.
sub load_modules {
	my @missing_modules = ();
	foreach( @_ ) {
		eval "require $_";
		push @missing_modules, $_ if $@;	
	}
	if( @missing_modules ) {
		print "Missing perl modules: @missing_modules\n";
		return 0;
	}
	return 1;
}


# NAME
#	PluginReport
# SYNOPSIS
#	$report = new PluginReport;
#   $report->{label1} = "value1";
#   $report->{label2} = "value2";
#	print $report->text(qw/label1 label2/);
package PluginReport;

sub new {
	my ($proto,%p) = @_;
	my $class = ref($proto) || $proto;
	my $self  = bless {}, $class;
	$self->{$_} = $p{$_} foreach keys %p;
	return $self;
}

sub text {
	my ($self,@labels) = @_;
	my @report = map { "$self->{$_} $_" } grep { defined $self->{$_} } @labels;
	my $text = join(", ", @report);
	return $text;
}


package main;
1;

__END__


=pod

=head1 NAME

check_imap_quota - connects to an IMAP account and checks the quota

=head1 SYNOPSIS

 check_imap_quota -vV
 check_imap_quota -?
 check_imap_quota --help

=head1 OPTIONS

=over

=item --warning <seconds>

Warn if it takes longer than <seconds> to connect to the IMAP server. Default is 15 seconds.
Also known as: -w <seconds>

=item --critical <seconds>

Return a critical status if it takes longer than <seconds> to connect to the IMAP server. Default is 30 seconds.
See also: --capture-critical <messages>
Also known as: -c <seconds>

=item --timeout <seconds>

Abort with critical status if it takes longer than <seconds> to connect to the IMAP server. Default is 60 seconds.
The difference between timeout and critical is that, with the default settings, if it takes 45 seconds to 
connect to the server then the connection will succeed but the plugin will return CRITICAL because it took longer
than 30 seconds.
Also known as: -t <seconds> 

=item --hostname <server>

Address or name of the IMAP server. Examples: mail.server.com, localhost, 192.168.1.100
Also known as: -H <server>

=item --port <number>

Service port on the IMAP server. Default is 143. If you use SSL, default is 993.
Also known as: -p <number>

=item --username <username>

=item --password <password>

Username and password to use when connecting to IMAP server. 
Also known as: -U <username> -P <password>

=item --mailbox <mailbox>

Use this option to specify the mailbox to search for messages. Default is INBOX. 
Also known as: -m <mailbox>

=item --ssl

=item --nossl

Enable SSL protocol. Requires IO::Socket::SSL. 

Using this option automatically changes the default port from 143 to 993. You can still
override this from the command line using the --port option.

Use the nossl option to turn off the ssl option.

=item --hires

Use the Time::HiRes module to measure time, if available.

=item --verbose

Display additional information. Useful for troubleshooting. Use together with --version to see the default
warning and critical timeout values.

If the selected mailbox was not found, you can use verbosity level 3 (-vvv) to display a list of all
available mailboxes on the server.

Also known as: -v

=item --version

Display plugin version and exit.
Also known as: -V

=item --help

Display this documentation and exit. Does not work in the ePN version. 
Also known as: -h

=item --usage

Display a short usage instruction and exit. 

=back

=head1 EXAMPLES

=head2 Report how many emails are in the mailbox

 $ check_imap_receive -H mail.server.net --username mailuser --password mailpass
 -s ALL --nodelete

 IMAP RECEIVE OK - 1 seconds, 7 found

=head2 Report the email with the highest value

Suppose your mailbox has some emails from an automated script and that a message
from this script typically looks like this (abbreviated):

 To: mailuser@server.net
 From: autoscript@server.net
 Subject: Results of Autoscript
 Date: Wed, 09 Nov 2005 08:30:40 -0800
 Message-ID: <auto-000000992528@server.net>

 Homeruns 5

And further suppose that you are interested in reporting the message that has the
highest number of home runs, and also to leave this message in the mailbox for future
checks, but remove the other matching messages with lesser values:

 $ check_imap_receive -H mail.server.net --username mailuser --password mailpass
 -s SUBJECT -s "Results of Autoscript" --capture-max "Homeruns (\d+)"  --nodelete-captured

 IMAP RECEIVE OK - 1 seconds, 3 found, 1 captured, 5 max, 2 deleted

=head2 Troubleshoot your search parameters

Add the --nodelete and --imap-retries=1 parameters to your command line.

=head1 EXIT CODES

Complies with the Nagios plug-in specification:
 0		OK			The plugin was able to check the service and it appeared to be functioning properly
 1		Warning		The plugin was able to check the service, but it appeared to be above some "warning" threshold or did not appear to be working properly
 2		Critical	The plugin detected that either the service was not running or it was above some "critical" threshold
 3		Unknown		Invalid command line arguments were supplied to the plugin or the plugin was unable to check the status of the given hosts/service

=head1 NAGIOS PLUGIN NOTES

Nagios plugin reference: http://nagiosplug.sourceforge.net/developer-guidelines.html

This plugin does NOT use Nagios DEFAULT_SOCKET_TIMEOUT (provided by utils.pm as $TIMEOUT) because
the path to utils.pm must be specified completely in this program and forces users to edit the source
code if their install location is different (if they realize this is the problem). You can view
the default timeout for this module by using the --verbose and --version options together.  The
short form is -vV.

Other than that, it attempts to follow published guidelines for Nagios plugins.

=head1 SEE ALSO

http://nagios.org/
http://search.cpan.org/~djkernen/Mail-IMAPClient-2.2.9/IMAPClient.pod
http://search.cpan.org/~markov/Mail-IMAPClient-3.00/lib/Mail/IMAPClient.pod

=head1 CHANGES

 Fri Nov 11 04:53:09 AST 2011
 + version 0.1 created with quota code contributed by Johan Romme

 Tue Dec 20 17:38:04 PST 2011
 + fixed bug where a quota of 0 was reported as an incorrect response from the server, thanks to Eike Arndt
 + version 0.2

=head1 AUTHOR

Jonathan Buhacoff <jonathan@buhacoff.net>

=head1 COPYRIGHT AND LICENSE

 Copyright (C) 2011 Jonathan Buhacoff

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.

 http://www.gnu.org/licenses/gpl.txt

=cut

