source: trunk/third/sendmail/contrib/etrn.pl @ 19204

#!/usr/local/bin/perl -w
#
# Copyright (c) 1996-2000 by John T. Beck <john@beck.org>
# All rights reserved.
#
# Copyright (c) 2000 by Sun Microsystems, Inc.
# All rights reserved.
#
#ident  "@(#)etrn.pl    1.1     00/09/06 SMI"

require 5.005;                          # minimal Perl version required
use strict;
use English;

# hardcoded constants, should work fine for BSD-based systems
use Socket;
use Getopt::Std;
use vars qw($opt_v);
my $sockaddr = 'S n a4 x8';

# system requirements:
#       must have 'hostname' program.

my $port = 'smtp';
select(STDERR);

chop(my $name = `hostname || uname -n`);

(my $hostname, my $aliases, my $type, my $len, undef) = gethostbyname($name);

my $usage = "Usage: $PROGRAM_NAME [-v] host [args]";
getopts('v');
my $verbose = $opt_v;
my $server = shift(@ARGV);
my @hosts = @ARGV;
die $usage unless $server;
my @cwfiles = ();
my $alarm_action = "";

if (!@hosts) {
        push(@hosts, $hostname);

        open(CF, "</etc/mail/sendmail.cf") ||
            die "open /etc/mail/sendmail.cf: $ERRNO";
        while (<CF>){
                # look for a line starting with "Fw"
                if (/^Fw.*$/) {
                        my $cwfile = $ARG;
                        chop($cwfile);
                        my $optional = /^Fw-o/;
                        # extract the file name
                        $cwfile =~ s,^Fw[^/]*,,;

                        # strip the options after the filename
                        $cwfile =~ s/ [^ ]+$//;

                        if (-r $cwfile) {
                                push (@cwfiles, $cwfile);
                        } else {
                                die "$cwfile is not readable" unless $optional;
                        }
                }
                # look for a line starting with "Cw"
                if (/^Cw(.*)$/) {
                        my @cws = split (' ', $1);
                        while (@cws) {
                                my $thishost = shift(@cws);
                                push(@hosts, $thishost)
                                    unless $thishost =~ "$hostname|localhost";
                        }
                }
        }
        close(CF);

        for my $cwfile (@cwfiles) {
                if (open(CW, "<$cwfile")) {
                        while (<CW>) {
                                next if /^\#/;
                                my $thishost = $ARG;
                                chop($thishost);
                                push(@hosts, $thishost)
                                    unless $thishost =~ $hostname;
                        }
                        close(CW);
                } else {
                        die "open $cwfile: $ERRNO";
                }
        }
}

($name, $aliases, my $proto) = getprotobyname('tcp');
($name, $aliases, $port) = getservbyname($port, 'tcp')
        unless $port =~ /^\d+/;

# look it up

($name, $aliases, $type, $len, my $thataddr) = gethostbyname($server);
(!defined($name)) && die "gethostbyname failed, unknown host $server";
                                
# get a connection
my $that = pack($sockaddr, &AF_INET, $port, $thataddr);
socket(S, &AF_INET, &SOCK_STREAM, $proto)
        || die "socket: $ERRNO";
print "server = $server\n" if (defined($verbose));
&alarm("connect to $server");
if (! connect(S, $that)) {
        die "cannot connect to $server: $ERRNO\n";
}
alarm(0);
select((select(S), $OUTPUT_AUTOFLUSH = 1)[0]);  # don't buffer output to S

# read the greeting
&alarm("greeting with $server");
while (<S>) {
        alarm(0);
        print if $verbose;
        if (/^(\d+)([- ])/) {
                # SMTP's initial greeting response code is 220.
                if ($1 != 220) {
                        &alarm("giving up after bad response from $server");
                        &read_response($2, $verbose);
                        alarm(0);
                        print STDERR "$server: NOT 220 greeting: $ARG"
                                if ($verbose);
                }
                last if ($2 eq " ");
        } else {
                print STDERR "$server: NOT 220 greeting: $ARG"
                        if ($verbose);
                close(S);
        }
        &alarm("greeting with $server");
}
alarm(0);
        
&alarm("sending ehlo to $server");
&ps("ehlo $hostname");
my $etrn_support = 0;
while (<S>) {
        if (/^250([- ])ETRN(.+)$/) {
                $etrn_support = 1;
        }
        print if $verbose;
        last if /^\d+ /;
}
alarm(0);

if ($etrn_support) {
        print "ETRN supported\n" if ($verbose);
        &alarm("sending etrn to $server");
        while (@hosts) {
                $server = shift(@hosts);
                &ps("etrn $server");
                while (<S>) {
                        print if $verbose;
                        last if /^\d+ /;
                }
                sleep(1);
        }
} else {
        print "\nETRN not supported\n\n"
}

&alarm("sending 'quit' to $server");
&ps("quit");
while (<S>) {
        print if $verbose;
        last if /^\d+ /;
}
close(S);
alarm(0);

select(STDOUT);
exit(0);

# print to the server (also to stdout, if -v)
sub ps
{
        my ($p) = @_;
        print ">>> $p\n" if $verbose;
        print S "$p\n";
}

sub alarm
{
        ($alarm_action) = @_;
        alarm(10);
        $SIG{ALRM} = 'handle_alarm';
}

sub handle_alarm
{
        &giveup($alarm_action);
}

sub giveup
{
        my $reason = @_;
        (my $pk, my $file, my $line);
        ($pk, $file, $line) = caller;

        print "Timed out during $reason\n" if $verbose;
        exit(1);
}

# read the rest of the current smtp daemon's response (and toss it away)
sub read_response
{
        (my $done, $verbose) = @_;
        (my @resp);
        print my $s if $verbose;
        while (($done eq "-") && ($s = <S>) && ($s =~ /^\d+([- ])/)) {
                print $s if $verbose;
                $done = $1;
                push(@resp, $s);
        }
        return @resp;
}