#!/usr/bin/perl
#
# nntp.monitor
# example: monitor nntp.monitor -g groupname -u user -a password
#
# Connect to an nntp server which possibly requires authentication, and
# wait for the right output.
#
# For use with "mon".
#
# Arguments are "-p port -t timeout [-g group] [-f] host [host...] -u username -a password"
#
# This monitor connects to the NNTP server(s), checks for a greeting, logs in,
# then performs a "mode reader" and a "group (groupname)", and then disconnects.
# If the group is not specified by the -g option, then "control" is assumed.
#
# if "-f" is supplied, then it is assumed that a feeder is being tested,
# and the "mode reader" and "group (groupname)" commands are not executed.
#
# Adapted from "http.monitor" by
# Jim Trocki, trockij@arctic.org
# authentication support added by
# Kai Schaetzl/conactive.com
#
# http.monitor written by
#
# Jon Meek
# American Cyanamid Company
# Princeton, NJ
#
# $Id: nntp.monitor,v 1.2.2.1 2007/05/03 19:55:40 trockij Exp $
#
#    Copyright (C) 1998, Jim Trocki
#
#    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 English;

getopts ("fg:p:t:d:u:a:");
$GROUP = $opt_g || 'control';
$PORT = $opt_p || 119;
$TIMEOUT = $opt_t || 30;
$FEEDER = $opt_f;
$DEBUG = $opt_d || "";
$USER = $opt_u || '';
$PASS = $opt_a || '';

@failures = ();

foreach $host (@ARGV) {

    if (! &nntpGET($host, $PORT)) {
	push (@failures, $host);
    }
}

if (@failures == 0) {
    exit 0;
}

print join (" ", sort @failures), "\n";

exit 1;


sub nntpGET {
    use Socket;
    use Sys::Hostname;

    my($Server, $Port) = @_;
    my($ServerOK, $TheContent);

    $ServerOK = 0;

    $TheContent = '';

    $Path = '/';

###############################################################
    eval {

	local $SIG{ALRM} = sub { die "Timeout Alarm" };
	alarm $TIMEOUT;
	$result = &OpenSocket($Server, $Port); # Open a connection to the server
	if ($result == 0) { # Failure to open the socket
	    print "Unable to open socket\n" if $DEBUG;
	    return '';
	}

	#
	# welcome message
	#
	$in = <S>;
	if ($in !~ /^2\d\d/) {
	    alarm 0;
	    print "No welcome message\n" if $DEBUG;
	    return 0;
	}

	if (!$FEEDER) {
		if ($USER ne "")
		{
		    # user
		    print S "authinfo user $USER\r\n";
		    $in = <S>;
		    if ($in !~ /^381/) {
		    alarm 0;
		    print "No reaction to authinfo user\n" if $DEBUG;
			    return 0;
		    }
		    # password
		    print S "authinfo pass $PASS\r\n";
		    $in = <S>;
		    if ($in !~ /^281/) {
		    	alarm 0;
		    	print "No reaction to authinfo pass or wrong password\n" if $DEBUG;
			return 0;
		    }
		}
	    #
	    # mode reader, wait for OK response
	    #
	    print S "mode reader\r\n";

	    $in = <S>;
	    if ($in !~ /^2\d\d/) {
		alarm 0;
		print "Unable to perform 'mode reader'\n" if $DEBUG;
		return 0;
	    }

	    #
	    # select $GROUP group, wait for OK response
	    #
	    print S "group $GROUP\r\n";

	    $in = <S>;
	    if ($in !~ /^2\d\d/) {
		alarm 0;
		print "Unable to select group '$GROUP'\n" if $DEBUG;
		return 0;
	    }
	}

	#
	# log out
	#
	print S "quit\r\n";

	$in = <S>;
	if ($in !~ /^2\d\d/) {
	    alarm 0;
	    print "No response on 'quit' command.\n" if $DEBUG;
	    return 0;
	}

	$ServerOK = 1;

	close(S);
	alarm 0; # Cancel the alarm

    };

    if ($EVAL_ERROR and ($EVAL_ERROR =~ /^Timeout Alarm/)) {
	print "**** Time Out\n";
	return 0;
    }
    return $ServerOK;

}

sub OpenSocket {
#
# Make a Berkeley socket connection between this program and a TCP port
#  on another (or this) host. Port can be a number or a named service
#
    local($OtherHostname, $Port) = @_;
    local($OurHostname, $sockaddr, $name, $aliases, $proto, $type, $len,
	  $ThisAddr, $that);
    $OurHostname = &hostname;

    ($name, $aliases, $proto) = getprotobyname('tcp');
    ($name, $aliases, $Port) = getservbyname($Port, 'tcp') unless $Port =~ /^\d+$/;
    ($name, $aliases, $type, $len, $ThisAddr) = gethostbyname($OurHostname);
    ($name, $aliases, $type, $len, $OtherHostAddr) = gethostbyname($OtherHostname);

    my $that = sockaddr_in ($Port, $OtherHostAddr);

    $result = socket(S, &PF_INET, &SOCK_STREAM, $proto) || return undef;

    $result = connect(S, $that) || return undef;

    select(S); $| = 1; select(STDOUT);      # set S to be un-buffered
    return 1;                               # success
}
