#!/usr/bin/perl 

# 
# mailloop.monitor - sends email to mailboxes that are expected to send 
# the mail back to the sender. Probably not hard to do with procmail, etc. 
# I've only used a reflector agent for Lotus Notes. Instead of "hosts" in 
# a hostgroup, use email addresses you want to send bounce tests to. The 
# code still refers to these as hosts. 
# 
# You can use as many addresses as you'd like, but you'll need to use a 
# unique from address for each hostgroup that calls this monitor, because 
# it eats all the mail this running copy of the monitor didn't send. 
# Otherwise, previously delayed mail might lay around forever. 
# 
# The monitor then polls a POP3 account for the mail it sent. Don't use 
# that mailbox for anything else, the monitor will delete all your mail! 
# I'm not kidding, I didn't say "might", it *will*. 
# 
# This monitor assumes the local sendmail knows how to get the mail to 
# the the first relay in the loop you're testing. It also assumes that 
# the last host knows to deliver mail sent to the configured from 
# address so that it shows up in the POP server we poll. 
# 
# Takes 5 options: 
# -d Debug Mode. Not really compatible with normal mon scheduling, 
# because it doesn't log to syslog or anything, just print to STDOUT. 
# You'll have to call the monitor by hand to use this option. 
# Mostly helpful to debug your POP/SMTP setup. 
# 
# -f Set the from address, this option will also set the POP user to 
# all the bits before the '@'. So, don't do any wild aliasing... 
# 
# -p Set the POP password. Defaults to null password 
# 
# -s Set the POP server. Defaults to localhost. 
# 
# -t Standard monitor timeout option. 
# 

# 
# $Id: mailloop.monitor,v 1.3 2000/02/11 23:25:23 bill Exp $ 
# 
# Copyright 2000 Shared Medical Systems, Inc. 
# Author: Bill Smargiassi 
# Email: william.smargiassi@smed.com 
# 
# 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 2 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, write to the Free Software 
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 
# 

use Getopt::Std; 
use Mail::Sendmail; 
use POSIX; 
use Mail::POP3Client; 

sub dbgprint { 
    my ($str) = @_; 

    print $str, "\n" if $DEBUG; 
} 

# "check sum of tests left", not to be confused with a checksum :) 
sub checksum { 
    my $sum; 

    $sum = 0; 
    foreach $id (keys %check) { 
     $sum += $check{$id}; 
    } 
    dbgprint "sum is " . $sum; 
    return $sum; 
} 

sub diefailures { 
    my $hosts, @parts; 

    $hosts = ''; 
    foreach $id (keys %check) { 
     if ($check{$id}) { 
         @parts = split(/ /, $id); 
         $hosts .= $parts[0]; 
     } 
    } 
    dbgprint "hosts is " . $hosts; 
    print $hosts, "\n"; 
    exit 1; 
} 

getopts("df:p:s:t:"); 
$Timeout = $opt_t || 900; 

$hostname = `hostname`; 
$fromaddr = "mailloop\@$hostname"; 
# popname is inferred from fromaddr if set with -f opt 
$popname = 'mailloop'; 
if ($opt_f) { 
    $fromaddr = $opt_f; 
    @parts = split(/\@/, $opt_f); 
    $popname = $parts[0]; 
} 
$poppass = $opt_p || 'mailloop'; 

$popserv = $opt_s || 'localhost'; 

$DEBUG = $opt_d || 0; 

dbgprint "Timeout = $Timeout"; 

$failures = ""; 

foreach $reflect (@ARGV) { 
    # Send some mail to the reflector address 
    $id = "$reflect " . strftime("%Y%m%d%H%M%S", localtime(time)); 
    dbgprint "Sending mail: $id"; 
    %mail = ( To => $reflect, 
           From => $fromaddr, 
           Message => "REFL: $id" 
           ); 

    # remember the id for later POP retrieval 
    $check{$id} = 1; 

    if (sendmail %mail) { } 
    else { $failures .= "Error sending mail: $Mail::Sendmail::error " } 
} 

dbgprint "Done sending mail"; 

if ($failures) {die $failures} 

local $SIG{TERM} = \&diefailures; 

$starttime = time; 

# look for replies 
$pop = new Mail::POP3Client( USER => $popname, 
                    PASSWORD => $poppass, 
                    HOST => $popserv, 
                    DEBUG => $DEBUG); 

while(checksum()) { 
    if ((time - $starttime) > $Timeout) { 
     diefailures(); 
    } 
    sleep(30); 
    dbgprint "Logging in..."; 
    $pop->Connect; 
    dbgprint "There are " . $pop->Count . " messages"; 
    for ($i = 1; $i <= $pop->Count; $i++) { 
     $id = ""; 
     @lines = split(/\n/, $pop->Body($i)); 
     foreach $line (@lines) { 
         dbgprint $line; 
         if ($line =~ m/REFL: (\S+ \d+)/g) { 
          $id = $1; 
          dbgprint "Found: $id"; 
         } 
     } 
     $check{$id} = 0; 
     $pop->Delete($i); 
    } 
    dbgprint "Logging out"; 
    $pop->Close; 
} 

exit 0;