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|
#!/usr/bin/perl
use strict;
use POSIX qw(strftime);
my $VERSION = '0.7.3';
my $COPYRIGHT = 'Copyright (C) 2005-2011 Jonathan Buhacoff <mail_redacted_for_web>';
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;
|