zabbix-helpers/check_email_delivery/check_email_delivery-0.7.1b/check_smtp_send

#!/usr/bin/perl
use strict;
use POSIX qw(strftime);
my $VERSION = '0.7.3';
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 );

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

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

Getopt::Long::Configure("bundling");
my $verbose = 0;
my $help = "";
my $help_usage = "";
my $show_version = "";
my $smtp_server = "";
my $default_smtp_port = "25";
my $default_smtp_ssl_port = "465";
my $default_smtp_tls_port = "587";
my $smtp_port = "";
my @mailto = ();
my $mailfrom = "";
my @header = ();
my $body = "";
my $stdin = "";
my $template = "";
my $expect_response = "250";
my $warntime = 15;
my $criticaltime = 30;
my $timeout = 60;
my $tls = 0;
my $ssl = 0;
my $auth_method = undef;
my $username = "";
my $password = "";
my $time_hires = "";
my $mx_lookup = 0;
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,
	# smtp settings
	"H|hostname=s"=>\$smtp_server,"p|port=i"=>\$smtp_port,
	"mailto=s"=>\@mailto, "mailfrom=s",\$mailfrom,
	"header=s"=>\@header, "body=s"=>\$body,	"stdin"=>\$stdin,
	"template!"=>\$template,
	# SSL/TLS/auth options
	"tls!"=>\$tls, "ssl!"=>\$ssl, "auth=s"=>\$auth_method,
	"U|username=s"=>\$username,"P|password=s"=>\$password,
	# Server response
	"E|expect-response=s"=>\$expect_response,
	# 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};
}

if( $smtp_server eq "" && scalar(@mailto) == 1 ) {
	# no SMTP server specified but one mailto address given means we can look up the MX record
	$mx_lookup = 1;
}

my @required_module = ();
push @required_module, 'Net::SMTP::SSL' if $ssl;
push @required_module, ('MIME::Base64','Authen::SASL') if $ssl && $username;
push @required_module, 'Net::SMTP::TLS' if $tls;
push @required_module, 'Net::SMTP_auth' if $auth_method and not $tls; # whereas if auth_method and tls we use TLS_auth, which is included in this script!
push @required_module, 'Text::Template' if $template;
push @required_module, 'Net::DNS' if $mx_lookup;
push @required_module, 'Email::Address' if $mx_lookup;
exit $status{UNKNOWN} unless load_modules(@required_module);


# split up @mailto if commas were used instead of multiple options
@mailto = split(/,/,join(',',@mailto));

if( $help_usage ||
	(
	($smtp_server eq "" && !$mx_lookup) || scalar(@mailto)==0 || $mailfrom eq ""
	) 
  ) {
	print "Usage: $0 [-H host [-p port]] --mailto recipient\@your.net [--mailto recipient2\@your.net ...] --mailfrom sender\@your.net --body 'some text' [-w <seconds>] [-c <seconds>]\n";
	exit $status{UNKNOWN};
}

# initialize
my $report = new PluginReport;
my $time_start = time;
my $actual_response = undef;
my @warning = ();
my @critical = ();

my $smtp_debug = 0;
$smtp_debug = 1 if $verbose >= 3;

# default date and message id headers
push @header, default_date_header() unless find_header("Date",@header);
push @header, default_messageid_header() unless find_header("Message-ID",@header);

# look up MX server if necessary
if( $mx_lookup ) {
	my $addr = Email::Address->new( undef, $mailto[0] );
	my $mx_domain = $addr->host;
	print "MX lookup " . $mx_domain . "\n" if $verbose > 1;
	my $res = Net::DNS::Resolver->new;
	my @mx = Net::DNS::mx($res, $mx_domain);
	if( @mx ) {
		# use the first server
		foreach my $rr (@mx) {
			print "pref : " . $rr->preference . " exchange: " . $rr->exchange . "\n" if $verbose > 2;			
		}
		$smtp_server = $mx[0]->exchange;
		print "smtp server: $smtp_server\n" if $verbose;
	}
	else {
		print "SMTP SEND CRITICAL - Cannot find MX records for $mx_domain\n";
		exit $status{CRITICAL};			
	}
}

# connect to SMTP server
# create the smtp handle using Net::SMTP, Net::SMTP::SSL, Net::SMTP::TLS, or an authentication variant
my $smtp; 
eval {
	if( $tls and $auth_method ) {
		$smtp_port = $default_smtp_tls_port unless $smtp_port;
		$smtp = TLS_auth->new($smtp_server, Timeout=>$timeout, Port=>$smtp_port, User=>$username, Password=>$password, Auth_Method=>$auth_method);
		if( $smtp ) {
			my $message = oneline($smtp->message());
			die "cannot connect with TLS/$auth_method: $message" if $smtp->code() =~ m/53\d/;
		}
	}
	elsif( $tls ) {
		$smtp_port = $default_smtp_tls_port unless $smtp_port;
		$smtp = Net::SMTP::TLS->new($smtp_server, Timeout=>$timeout, Port=>$smtp_port, User=>$username, Password=>$password);
		if( $smtp ) {
			my $message = oneline($smtp->message());
			die "cannot connect with TLS: $message" if $smtp->code() =~ m/53\d/;
		}
	}
	elsif( $ssl ) {
		$smtp_port = $default_smtp_ssl_port unless $smtp_port;
		$smtp = Net::SMTP::SSL->new($smtp_server, Port => $smtp_port, Timeout=>$timeout,Debug=>$smtp_debug);
		if( $smtp && $username )  {
			$smtp->auth($username, $password);
			my $message = oneline($smtp->message());
			die "cannot connect with SSL/password: $message" if $smtp->code() =~ m/53\d/;
		}	
	}
	elsif( $auth_method ) {
		$smtp_port = $default_smtp_port unless $smtp_port;
		$smtp = Net::SMTP_auth->new($smtp_server, Port=>$smtp_port, Timeout=>$timeout,Debug=>$smtp_debug);	
		if( $smtp ) {
			$smtp->auth($auth_method, $username, $password);
			my $message = oneline($smtp->message());
			die "cannot connect with SSL/$auth_method: $message" if $smtp->code() =~ m/53\d/;
		}			
	}
	else {
		$smtp_port = $default_smtp_port unless $smtp_port;
		$smtp = Net::SMTP->new($smtp_server, Port=>$smtp_port, Timeout=>$timeout,Debug=>$smtp_debug);	
		if( $smtp && $username ) {
			$smtp->auth($username, $password);
			my $message = oneline($smtp->message());
			die "cannot connect with password: $message" if $smtp->code() =~ m/53\d/;
		}	
	}
};
if( $@ ) {
	$@ =~ s/\n/ /g; # the error message can be multiline but we want our output to be just one line
	print "SMTP SEND CRITICAL - $@\n";
	exit $status{CRITICAL};	
}
unless( $smtp ) {
	print "SMTP SEND CRITICAL - Could not connect to $smtp_server port $smtp_port\n";
	exit $status{CRITICAL};
}
my $time_connected = time;

# add the monitored server's banner to the report
if( $tls ) {
	$report->{banner} = "";	
}
elsif( $ssl ) {
	$report->{banner} = $smtp->banner || "";
	chomp $report->{banner};		
}
else {
	$report->{banner} = $smtp->banner || "";
	chomp $report->{banner};	
}


# send email
if( $stdin ) {
	$body = "";
	while(<STDIN>) {
		$body .= $_;
	}
}

# if user wants to use template substitutions, this is the place to process body and headers
if( $template ) {
	foreach my $item (@header,$body) {
		my $t = Text::Template->new(TYPE=>'STRING',SOURCE=>$item,PACKAGE=>'SmtpMessageTemplate');
		$item = $t->fill_in(PREPEND=>q{package SmtpMessageTemplate;});
#		print "item: $item\n";
	}
}


$smtp->mail($mailfrom);
foreach( @mailto ) {
	# the two SMTP modules have different error reporting mechanisms:
	if( $tls ) {
		# Net::SMTP::TLS croaks when the recipient is rejected
		eval {
			$smtp->to($_);			
		};
		if( $@ ) {
			print "SMTP SEND CRITICAL - Could not send to $_\n";
			print "Reason: $@\n" if $verbose;
			exit $status{CRITICAL};			
		}
	}
	else {
		# Net::SMTP returns false when the recipient is rejected
		my $to_returned = $smtp->to($_);
		if( !$to_returned ) { 
			print "SMTP SEND CRITICAL - Could not send to $_\n";
			print "Reason: Recipient rejected or authentication failed\n" if $verbose;
			exit $status{CRITICAL};
		}
	}
}

# Net::SMTP::TLS doesn't implement code() so we need to wrap calls in eval to get our error messages

	# start data transfer (expect response 354)
	$smtp->data();
	
	# send data
	$smtp->datasend("To: ".join(", ",@mailto)."\n");
	$smtp->datasend("From: $mailfrom\n");
	foreach( @header ) {
		$smtp->datasend("$_\n");
	}
	$smtp->datasend("\n");
	$smtp->datasend($body);
	$smtp->datasend("\n");
	
eval {
	# end data transfer (expect response 250)
	$smtp->dataend();	
};
if( $@ ) {
	$actual_response = $tls ? get_tls_error($@) : $smtp->code();
}
else {
	$actual_response = $tls ? "250" : $smtp->code();	# no error means we got 250		
}

eval {
	# disconnect from SMTP server (expect response 221)
	$smtp->quit();
};
if( $@ ) {
	push @warning, "Error while disconnecting from $smtp_server";
}

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

push @warning, "connection time more than $warntime" if( $time_connected - $time_start > $warntime );
push @critical, "connection time more than $criticaltime" if( $time_connected - $time_start > $criticaltime );
push @critical, "response was $actual_response but expected $expect_response" if ( $actual_response ne $expect_response );

# print report and exit with known status
my $perf_data = "elapsed=".$report->{seconds}."s;$warntime;$criticaltime"; # TODO: need a component for safely generating valid perf data format. for notes on the format, see http://www.perfparse.de/tiki-view_faq.php?faqId=6 and http://nagiosplug.sourceforge.net/developer-guidelines.html#AEN185
my $short_report = $report->text(qw/seconds/) . " | $perf_data";
my $long_report = join("", map { "$_: $report->{$_}\n" } qw/banner/ );
if( scalar @critical ) {
	my $crit_alerts = join(", ", @critical);
	print "SMTP SEND CRITICAL - $crit_alerts; $short_report\n";
	print $long_report if $verbose;
	exit $status{CRITICAL};
}
if( scalar @warning ) {
	my $warn_alerts = join(", ", @warning);
	print "SMTP SEND WARNING - $warn_alerts; $short_report\n";
	print $long_report if $verbose;
	exit $status{WARNING};
}
print "SMTP SEND OK - $short_report\n";
print $long_report if $verbose;
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;
}

# utility to extract error codes out of Net::SMTP::TLS croak messages
sub get_tls_error {
	my ($errormsg) = @_;
	$errormsg =~ m/: (\d+) (.+)/;
	my $code = $1;		
	return $code;
}

# looks for a specific header in a list of headers; returns true if found
sub find_header {
	my ($name, @list) = @_;
	return scalar grep { m/^$name: /i } @list;
}

# RFC 2822 date header
sub default_date_header {
	return strftime "Date: %a, %e %b %Y %H:%M:%S %z (%Z)", gmtime;
}

# RFC 2822 message id header
sub default_messageid_header {
	my $random = randomstring(16,qw/0 1 2 3 4 5 6 7 8 9 a b c d e f g h i j k l m n o p q r s t u v w x y z/);
	my $hostname = `hostname`;
	chomp $hostname;
	return "Message-ID: <".time.".".$random.".checksmtpsend@".$hostname.">";
}

# returns a random string of specified length using characters from specified set
sub randomstring {
	my ($length,@set) = @_;
	my $size = scalar @set;
	my $string = "";
	while($length--) {
		$string .= $set[int(rand($size))];
	}
	return $string;
}

# replaces all newlines in the input string with spaces
sub oneline {
	my ($input) = @_;
	$input =~ s/[\r\n]+/ /g;
	return $input;
}

# 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 SmtpMessageTemplate;

sub trim {
	my ($text) = @_;
	$text =~ s/^\s*//;
	$text =~ s/\s*$//;
	return $text;
}

# NAME
#   TLS_auth
# SYNOPSYS
#   
# Based on contribution by Brad Guillory
package TLS_auth;
#use Net::SMTP::TLS;
our @ISA = qw(Net::SMTP::TLS);
use Carp;
sub new {
	my ($proto,$server,%p) = @_;
	my $class = ref($proto) || $proto;
	#my $self = bless {}, $class;
	no strict 'refs';
	no warnings 'once';
	*Net::SMTP::TLS::login = *TLS_auth::login;  # override parent's login with ours so when it's called in the constructor, our overriden version will be used
	my $self = Net::SMTP::TLS->new($server,%p);
	return $self;
}


sub login {
	my ($self) = @_;
	my $type = $self->{features}->{AUTH};
	if(not $type){
		die "Server did not return AUTH in capabilities\n"; # croak
	}
#	print "Feature: $type\nAuth Method: $self->{Auth_Method}\n";
	if($type =~ /CRAM\-MD5/ and $self->{Auth_Method} =~ /CRAM\-MD5/i){
		$self->auth_MD5();
	}elsif($type =~ /LOGIN/ and $self->{Auth_Method} =~ /LOGIN/i){
		$self->auth_LOGIN();
	}elsif($type =~ /PLAIN/ and $self->{Auth_Method} =~ /PLAIN/i){
		#print "Calling auth_PLAIN\n";
		$self->auth_PLAIN();
	}else{
		die "Unsupported Authentication mechanism: $self->{Auth_Method}\n"; # croak
	}
}

    
package main;
1;

__END__

=pod

=head1 NAME

check_smtp_send - connects to an SMTP server and sends a message

=head1 SYNOPSIS

 check_smtp_send -vV
 check_smtp_send -?
 check_smtp_send --help

=head1 OPTIONS

=over

=item --warning <seconds>

Warn if it takes longer than <seconds> to connect to the SMTP 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 SMTP server. Default is 30 seconds.
Also known as: -c <seconds> 

=item --timeout <seconds>

Abort with critical status if it takes longer than <seconds> to connect to the SMTP 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 SMTP server. Examples: mail.server.com, localhost, 192.168.1.100

If not provided, and if there is only one --mailto address, the script will automatically look up the MX record
for the --mailto address and use that as the hostname. You can use this to check that your MX records are correct.
When omitting the --hostname option, it doesn't really make sense to specify --port, --username, or --password
but you can still do so and they will have their normal effect. To look up the MX records you need to have the
module Net::DNS and Email::Address installed.

Also known as: -H <server>

=item --port <number>

Service port on the SMTP server. Default is 25 for regular SMTP, 465 for SSL, and 587 for TLS.
Also known as: -p <number>

=item --tls

=item --notls

Enable TLS/AUTH protocol. Requires Net::SMTP::TLS, availble on CPAN.

When using this option, the default port is 587.
You can specify a port from the command line using the --port option.

Use the notls option to turn off the tls option.

Also, you may need to fix your copy of Net::SMTP::TLS. Here is the diff against version 0.12:

 254c254
 < 	$me->_command(sprintf("AUTH PLAIN %S",
 ---
 > 	$me->_command(sprintf("AUTH PLAIN %s",


=item --ssl

=item --nossl

Enable SSL protocol. Requires Net::SMTP::SSL and Authen::SASL, availble on CPAN.

When using this option, the default port is 465. You can override with the --port option.

Use the nossl option to turn off the ssl option.

=item --auth <method>

Enable authentication with Net::SMTP_auth (sold separately).
For example, try using --auth PLAIN or --auth CRAM-MD5.

=item --username <username>

=item --password <password>

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

=item --body <message>

Use this option to specify the body of the email message. If you need newlines in your message,
you might need to use the --stdin option instead.

=item --header <header>

Use this option to set an arbitrary header in the message. You can use it multiple times.

=item --stdin

Grab the body of the email message from stdin.

=item --mailto recipient@your.net

You can send a message to multiple recipients by repeating this option or by separating
the email addresses with commas (no whitespace allowed): 

$ check_smtp_send -H mail.server.net --mailto recipient@your.net,recipient2@your.net --mailfrom sender@your.net 

SMTP SEND OK - 1 seconds

=item --mailfrom sender@your.net

Use this option to set the "from" address in the email. 

=item --template

=item --notemplate

Enable (or disable) processing of message body and headers. Requires Text::Template.

Use this option to apply special processing to your message body and headers that allows you to use the
results of arbitrary computations in the text. For example, you can use this feature to send a message
containing the hostname of the machine that sent the message without customizing the plugin configuration
on each machine.

When you enable the --template option, the message body and headers are parsed by
Text::Template. Even a message body provided using the --stdin option will be parsed.
See the Text::Template manual for more information, but in general any expression
written in Perl will work. 

There is one convenience function provided to you, trim, which will remove leading and trailing whitespace
from its parameter. Here's an example:

 check_smtp_send -H mail.server.net --mailto recipient@your.net --mailfrom sender@your.net 
 --template --body 'hello, this message is from {use Sys::Hostname; hostname}' 
 --header 'Subject: test message from {trim(`whoami`)}'


=item --expect-response <code>

Use this option to specify which SMTP response code should be expected from the server
after the SMTP dialog is complete. The default is 250 (message accepted).

Also known as: -E <code>

=item --hires

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

=item --verbose

Display additional information. Useful for troubleshooting.

One --verbose will show extra information for OK, WARNING, and CRITICAL status.

Use one --verbose together with --version to see the default warning and critical timeout values.

Three --verbose (or -vvv) will show debug information, unless you're using --tls because Net::SMTP::TLS
does not have a Debug feature.

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 Send a message with custom headers

$ check_smtp_send -H mail.server.net --mailto recipient@your.net --mailfrom sender@your.net 
--body 'Homeruns 5' --header 'Subject: Hello, world!' --header 'X-Your-Header: Yes'

SMTP SEND OK - 1 seconds

=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 CHANGES

 Wed Oct 29 14:05:00 PST 2005
 + version 0.1

 Wed Nov  9 15:01:48 PST 2005
 + now using an inline PluginReport package to generate the report
 + added stdin option
 + copyright notice and GNU GPL
 + version 0.2

 Thu Apr 20 16:00:00 PST 2006 (by Geoff Crompton <geoff.crompton@strategicdata.com.au>)
 + added bailing if the $smtp->to() call fails
 + added support for mailto recipients separated by commas
 + version 0.2.1

 Tue Apr 24 21:17:53 PDT 2007
 + moved POD text to separate file in order to accomodate the new embedded-perl Nagios feature
 + version 0.2.3

 Fri Apr 27 20:26:42 PDT 2007
 + documentation now mentions every command-line option accepted by the plugin, including abbreviations
 + version 0.3
 
 Sun Oct 21 10:34:14 PDT 2007
 + added support for TLS and authentication via the Net::SMTP::TLS module. see --tls option.
 + version 0.4

 Sun Oct 21 13:54:26 PDT 2007
 + added support for SSL via the Net::SMTP::SSL module. see --ssl option.
 + port is no longer a required option. defaults to 25 for regular smtp, 465 for ssl, and 587 for tls.
 + added port info to the "could not connect" error message
 + version 0.4.1

 Tue Dec  4 07:42:32 PST 2007
 + added --usage option because the official nagios plugins have both --help and --usage
 + added --timeout option to match the official nagios plugins
 + fixed some minor pod formatting issues for perldoc
 + version 0.4.2

 Mon Feb 11 19:09:37 PST 2008
 + fixed a bug for embedded perl version, variable "%status" will not stay shared in load_modules
 + version 0.4.3

 Mon May 26 09:12:14 PDT 2008
 + fixed warning and critical messages to use "more than" or "less than" instead of the angle brackets, to make them more web friendly
 + version 0.4.4
 
 Wed Jul  2 07:12:35 PDT 2008
 + added --expect-response option submitted by Christian Kauhaus <kc@gocept.com>
 + added support for authentication via Net::SMTP_auth. see --auth option.
 + version 0.4.5

 Sun Oct  5 15:18:23 PDT 2008
 + added error handling for smtp server disconnects ungracefully during QUIT (gmail.com does)
 + version 0.4.6

 Thu Oct  1 12:09:35 PDT 2009
 + added --template option to allow arbitrary substitutions for body and headers, and provided one convenience function for trimming strings
 + added performance data for use with PNP4Nagios!
 + version 0.5.0

 Thu Oct  8 11:17:04 PDT 2009
 + added more detailed error messages when using --verbose
 + version 0.5.1

 Tue Feb  9 12:14:49 PST 2010
 + added support for combining --auth with --tls using a subclass of Net::SMTP::TLS submitted by Brad Guillory; please note that to use the "PLAIN" authentication type you need to patch your Net::SMTP:TLS because it has a bug in sub auth_PLAIN (sprintf %S instead of %s)
 + version 0.5.2

 Mon Jan  3 10:39:42 PST 2011
 + added default Date and Message-ID headers; Date header uses POSIX strftime and Message-ID header uses hostname command to get localhost name
 + version 0.7.0

 Fri May  6 08:35:09 AST 2011
 + added --hires option to enable use of Time::Hires if available
 + version 0.7.1

 Wed Jul  6 19:18:26 AST 2011
 + the --hostname is now optional; if not provided the plugin will lookup the MX record for the --mailto address (requires Net::DNS)
 + version 0.7.2

 Tue Dec 13 09:24:04 PST 2011
 + separated authentication errors from connection errors
 + version 0.7.3

=head1 AUTHOR

Jonathan Buhacoff <jonathan@buhacoff.net>

=head1 COPYRIGHT AND LICENSE

 Copyright (C) 2005-2011 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