Querying SSL/TLS capabilities of SMTP servers

[Justin]

On 2004-07-08T17:50:57+0200, Thomas Shaddack wrote:
> I cobbled up together a small bash shell script that does this. It lists 
> the MX records for a domain, and then tries to connect to each of them, 
> issue an EHLO command, disconnect, then list the output of the server, 
...

Or, in perl... though I wonder if there's a way to get capabilities with
Net::SMTP.  Might make this cleaner.


#!/usr/bin/perl

use IO::Socket;
use Net::DNS;

for ($i = 0; $i <= $#ARGV; $i++) {
    my @mx = mx($ARGV[$i]);
    foreach $record (@mx) {
	my $hastls = 0;
	my $mhost = IO::Socket::INET->new (
 		Proto => "tcp",
		PeerAddr => $record->exchange,
		PeerPort => "25",
		Timeout => "10"
	);
	print $mhost "EHLO I-love-my-country.whitehouse.gov\n";
	print $mhost "QUIT\n";
	while (<$mhost>) {
	    if (/STARTTLS/) {
		$hastls = 1;
		last;
	    }
	}
	print "$ARGV[$i] " . $record->preference . " " . $record->exchange;
	print $hastls ? " adv-tls\n" : " no-tls\n";
	close $mhost;
    }
}