-#! /usr/bin/perl -W
+#! /usr/bin/perl -w
#
-# checkmail Version 0.3 by Thomas Hochstein
+# checkmail Version 0.6.3 by Thomas Hochstein
#
# This script tries to verify the deliverability of (a) mail address(es).
#
-# Copyright (c) 2002-2010 Thomas Hochstein <thh@inter.net>
+# Copyright (c) 2002-2016 Thomas Hochstein <thh@thh.name>
#
# It can be redistributed and/or modified under the same terms under
# which Perl itself is published.
-our $VERSION = "0.3";
+our $VERSION = "0.6.3 (unreleased)";
################################# Configuration ################################
# Please fill in a working configuration!
# value used for HELO/EHLO - a valid hostname you own
helo => 'testhost.domain.example',
# value used for MAIL FROM: - a valid address under your control
- from => 'mailtest@testhost.domain.example',
- # a syntactically valid "random" - reliably not existing - localpart
- rand => 'ZOq62fow1i'
+ from => 'mailtest@testhost.domain.example'
);
################################### Modules ####################################
use strict;
use File::Basename;
use Getopt::Std;
+use Mail::Address;
use Net::DNS;
use Net::SMTP;
# read commandline options
my %options;
-getopts('Vhqlrf:m:', \%options);
+getopts('Vhqlrf:m:s:e:', \%options);
# -V: display version
if ($options{'V'}) {
- print "$myself v $VERSION\nCopyright (c) 2010 Thomas Hochstein <thh\@inter.net>\n";
+ print "$myself v $VERSION\nCopyright (c) 2002-2016 Thomas Hochstein <thh\@thh.name>\n";
print "This program is free software; you may redistribute it and/or modify it under the same terms as Perl itself.\n";
exit(100);
};
# display usage information if neither -f nor an address are present
if (!$options{'f'} and !$ARGV[0]) {
- print "Usage: $myself [-hqlr] [-m <host>] <address>|-f <file>\n";
+ print "Usage: $myself [-hqlr] [-m <host>]
[-s <from>] [-e <EHLO>] <address>|-f <file>\n";
print "Options: -V display copyright and version\n";
print " -h show documentation\n";
print " -q quiet (no output, just exit with 0/1/2/3)\n";
print " -l extended logging\n";
print " -r test random address to verify verification\n";
print " -m <host> no DNS lookup, just test this host\n";
+ print " -s <from> override configured value for MAIL FROM\n";
+ print " -e <EHLO> override configured value for EHLO\n";
print " <address> mail address to check\n\n";
print " -f <file> parse file (one address per line)\n";
exit(100);
};
+# -s / -e: override configuration
+$config{'from'} = $options{'s'} if defined($options{'s'});
+$config{'helo'} = $options{'e'} if $options{'e'};
+
# -f: open file and read addresses to @adresses
my @addresses;
if ($options{'f'}) {
my (%targets,$curstat,$status,$log,$message);
foreach (@addresses) {
my $address = $_;
- (undef,my $domain) = splitaddress($address);
- printf(" * Testing %s ...\n",$address) if !($options{'q'});
- $log .= "\n===== BEGIN $address =====\n";
- # get list of target hosts or take host forced via -m
- if (!$options{'m'}) {
- %targets = %{gettargets($domain,\$log)};
- } else {
- $message = sprintf("Connection to %s forced by -m.\n",$options{'m'});
- $log .= $message;
- print " $message" if !($options{'q'});
- # just one target host with preference 0
- $targets{$options{'m'}} = 0;
- };
- if (%targets) {
- $curstat = checkaddress($address,\%targets,\$log);
- } else {
+ # regexp taken from http://www.regular-expressions.info/email.html
+ # with escaping of "/" added two times and "*" changed to "+"
+ # in localpart, second alternative
+ if ($address !~ /^(?:[a-z0-9!#$%&'*+\/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+\/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f]+)")@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?$/i) {
+ printf(" > Address <%s> is syntactically INVALID.\n",$address) if !($options{'q'});
$curstat = 2;
- $message = 'DNS lookup failure';
- printf(" > Address is INVALID (%s).\n",$message) if !($options{'q'});
- $log .= $message . '.';
+ } else {
+ my $domain = Mail::Address->new('',$address)->host;
+ printf(" * Testing %s ...\n",$address) if !($options{'q'});
+ $log .= "\n===== BEGIN $address =====\n";
+ # get list of target hosts or take host forced via -m
+ if (!$options{'m'}) {
+ %targets = %{gettargets($domain,\$log)};
+ } else {
+ $message = sprintf("Connection to %s forced by -m.\n",$options{'m'});
+ $log .= $message;
+ print " $message" if !($options{'q'});
+ # just one target host with preference 0
+ $targets{$options{'m'}} = 0;
+ };
+ if (%targets) {
+ $curstat = checkaddress($address,\%targets,\$log);
+ } else {
+ $curstat = 2;
+ $message = 'DNS lookup failure';
+ printf(" > Address is INVALID (%s).\n",$message) if !($options{'q'});
+ $log .= $message . '.';
+ };
+ $log .= "====== END $address ======\n";
};
- $log .= "====== END $address ======\n";
$status = $curstat if (!defined($status) or $curstat > $status);
};
# no MX record found; log and try A record(s)
} else {
print_dns_result($domain,'MX',undef,$resolver->errorstring,$logr);
- print(" Falling back to A record ...\n") if !($options{'q'});
- # get A record(s)
+ print(" Falling back to A record(s) ...\n") if !($options{'q'});
+ # get A record(s)
+ # may get CNAMEs instead ...
if (my $query = $resolver->query($domain,'A','IN')) {
- print_dns_result($domain,'A',$query->header->ancount,undef,$logr);
+ print_dns_result($domain,'A/CNAME',$query->header->ancount,undef,$logr);
foreach my $rr ($query->answer) {
+ if ($rr->type ne 'A') {
+ # report CNAMEs and don't add them to target list
+ if ($rr->type eq 'CNAME') {
+ printf (" ~ '%s' is a CNAME for '%s' and will be resolved accordingly. \n",$rr->name,$rr->cname) if !($options{'q'});
+ $$logr .= sprintf("- CNAME resolved: %s -> %s\n",$rr->name,$rr->cname);
+ }
+ next;
+ }
$targets{$rr->address} = 0;
$$logr .= sprintf("- %s\n",$rr->address);
};
my ($success,$code,@message) = try_rcpt_to(\$smtp,$address,$logr);
# connection failure?
if ($success < 0) {
- $status = connection_failed();
+ $status = connection_failed(@message);
# delivery attempt was successful?
} elsif ($success) {
# -r: try random address (which should be guaranteed to be invalid)
if ($options{'r'}) {
- (undef,my $domain) = splitaddress($address);
- my ($success,$code,@message) = try_rcpt_to(\$smtp,$config{'rand'}.'@'.$domain,$logr);
+ my ($success,$code,@message) = try_rcpt_to(\$smtp,create_rand_addr(Mail::Address->new('',$address)->host),$logr);
# connection failure?
if ($success < 0) {
- $status = connection_failed();
+ $status = connection_failed(@message);
+ # reset status - the address has been checked and _is_ valid!
+ $status = 3;
+ print " > Address verification currently impossible. You'll have to try again or send a test mail ...\n" if !($options{'q'});
# verification impossible?
} elsif ($success) {
$status = 3;
- print " > Address verificaton impossible. You'll have to send a test mail ...\n" if !($options{'q'});
+ print " > Address verification impossible. You'll have to send a test mail ...\n" if !($options{'q'});
}
}
# if -r is not set or status was not set to 3: valid address
return $status;
}
-################################# splitaddress #################################
-# split mail address into local and domain part
-# IN : $address: a mail address
-# OUT: $local : local part
-# $domain: domain part
-sub splitaddress {
- my($address)=@_;
- (my $lp = $address) =~ s/^([^@]+)@.*/$1/;
- (my $domain = $address) =~ s/[^@]+\@(\S*)$/$1/;
- return ($lp,$domain);
+############################### create_rand_addr ###############################
+# create a random mail address
+# IN : $domain: the domain part
+# OUT: $address: the address
+sub create_rand_addr {
+ my($domain)=@_;
+ my $allowed = 'ABCDEFGHJKLMNPQRSTUVWXYZabcdefghjkmnpqrstuvwxyz23456789-+_=';
+ my $address = '';
+ while (length($address) < 15) {
+ $address .= substr($allowed, (int(rand(length($allowed)))),1);
+ };
+ return ($address.'@'.$domain);
};
################################ parse_dns_reply ###############################
# IN : \$smtp : a reference to an SMTP object
# $recipient: a mail address
# \$log : reference to the log (to be printed out via -l)
-# OUT: $success: true or false
+# OUT: $success: exit code (0 for false, 1 for true, -1 for tempfail)
# $code : SMTP status code
# $message: SMTP status message
# \$log will be changed
sub try_rcpt_to {
my($smtpr,$recipient,$logr)=@_;
$$logr .= sprintf("RCPT TO:<%s>\n",$recipient);
- my $success = $$smtpr->to($recipient);
+ my $success;
+ $$smtpr->to($recipient);
if ($$smtpr->code) {
log_smtp_reply($logr,$$smtpr->code,$$smtpr->message);
+ $success = analyze_smtp_reply($$smtpr->code,$$smtpr->message);
} else {
$success = -1;
$$logr .= "---Connection failure---\n";
return;
}
+############################### analyze_smtp_reply ##############################
+# analyze SMTP response codes and messages
+# IN : $code : SMTP status code
+# @message : SMTP status message
+# OUT: exit code (0 for false, 1 for true, -1 for tempfail)
+sub analyze_smtp_reply {
+ my($code,@message)=@_;
+ my $type = substr($code, 0, 1);
+ if ($type == 2) {
+ return 1;
+ } elsif ($type == 5) {
+ return 0;
+ } elsif ($type == 4) {
+ return -1;
+ };
+ return -1;
+}
+
############################## connection_failed ###############################
# print failure message and return status 1
+# IN : @message : SMTP status message
# OUT: 1
sub connection_failed {
- print " > Connection failure.\n" if !($options{'q'});
+ my(@message)=@_;
+ print " ! Connection failed or other temporary failure.\n" if !($options{'q'});
+ printf(" %s\n",join(' ',@message)) if @message;
return 1;
}
+
+__END__
+
+################################ Documentation #################################
+
+=head1 NAME
+
+checkmail - check deliverability of a mail address
+
+=head1 SYNOPSIS
+
+B<checkmail> [B<-Vhqlr>] [B<-m> I<host>] [-s I<sender>] [-e I<EHLO>] I<address>|B<-f> I<file>
+
+=head1 REQUIREMENTS
+
+=over 2
+
+=item -
+
+Perl 5.8 or later
+
+=item -
+
+File::Basename
+
+=item -
+
+Getopt::Std
+
+=item -
+
+Mail::Address I<(CPAN)>
+
+=item -
+
+Net::DNS I<(CPAN)>
+
+=item -
+
+Net::SMTP
+
+=back
+
+Furthermore you'll need a working DNS installation.
+
+=head1 DESCRIPTION
+
+checkmail checks the vailidity / deliverability of a mail address.
+You may submit just one address as the last argument or a file
+containing one address on each line using the B<-f> option.
+
+=head2 Configuration
+
+For the time being, all configuration is done in the script. You have
+to set the following elements of the %config hash:
+
+=over 4
+
+=item B<$config{'helo'}>
+
+The hostname to be used for I<HELO> or I<EHLO> in the SMTP dialog.
+
+=item B<$config{'from'}>
+
+The sender address to be used for I<MAIL FROM> while testing.
+May be empty ('') to set '<>' as MAIL FROM.
+
+=back
+
+You may override that configuration by using the B<-e> and B<-s>
+command line options.
+
+=head2 Usage
+
+After configuring the script you may run your first test with
+
+ checkmail user@example.org
+
+B<checkmail> will check the address for syntactic validity. If the
+address is valid, it will try to determine the mail exchanger(s) (MX)
+responsible for I<example.org> by querying the DNS for the respective
+MX records and then try to connect via SMTP (on port 25) to each of
+them in order of precedence (if necessary). It will run through the
+SMTP dialog until just before the I<DATA> stage, i.e. doing I<EHLO>,
+I<MAIL FROM> and I<RCPT TO>. If no MX is defined, B<checkmail> will
+fall back to the I<example.org> host itself, provided there is at
+least one A record defined in the DNS. CNAMEs will be accepted and
+resolved here. If there are neither MX nor A records for
+I<example.org>, mail is not deliverable and B<checkmail> will fail
+accordingly. If no host can be reached, B<checkmail> will fail,
+too. Finally B<checkmail> will fail if mail to the given recipient
+is not accepted by the respective host.
+
+If B<checkmail> fails, you'll not be able to deliver mail to that
+address - at least not using the configured sender address and from
+the host you're testing from. However, the opposite is not true: a
+mail you send may still not be delivered even if a test via
+B<checkmail> succeeds. The receiving entity may reject your mail after
+the I<DATA> stage, due to content checking or without any special
+reason, or it may even drop, filter or bounce your mail after finally
+accepting it. There is no way to be sure a mail will be accepted short
+of sending a real mail to the address in question.
+
+You may, however, try to detect hosts that will happily accept any and
+all recipient in the SMTP dialog and just reject your mail later on,
+for example to defeat exactly the kind of check you try to do.
+B<checkmail> will do that by submitting a recipient address that is
+known to be invalid; if that address is accepted, too, you'll know
+that you can't reliably check the validity of any address on that
+host. You can force that check by using the B<-r> option.
+
+If you don't want to see just the results of your test, you can get a
+B<complete log> of the SMTP dialog by using the B<-l> option. That may be
+helpful to test for temporary failure conditions.
+
+On the other hand you may use the B<-q> option to suppress all output;
+B<checkmail> will then terminate with one of the following B<exit
+status>:
+
+=over 4
+
+=item B<0>
+
+address(es) seem/seems to be valid
+
+=item B<1>
+
+temporary error (connection failure or temporary failure)
+
+=item B<2>
+
+address is invalid
+
+=item B<3>
+
+address cannot reliably be checked (test using B<-r> failed)
+
+=back
+
+You can do B<batch processing> using B<-f> and submitting a file with
+one address on each line. In that case the exit status is set to the
+highest value generated by testing all addresses, i.e. it is set to
+B<0> if and only if no adress failed, but to B<2> if even one address
+failed and to B<3> if even one addresses couldn't reliably be checked.
+
+And finally you can B<suppress DNS lookups> for MX and A records and
+just force B<checkmail> to connect to a particular host using the
+B<-m> option.
+
+B<Please note:> You shouldn't try to validate addresses while working
+from a dial-up or blacklisted host. If in doubt, use the B<-l> option
+to have a closer look on the SMTP dialog yourself.
+
+B<Please note:> To avoid shell expansion on addresses you submit to
+B<checkmail>, use B<batch processing>.
+
+=head1 OPTIONS
+
+=over 3
+
+=item B<-V> (version)
+
+Print out version and copyright information on B<checkmail> and exit.
+
+=item B<-h> (help)
+
+Print this man page and exit.
+
+=item B<-q> (quit)
+
+Suppress output and just terminate with a specific exit status.
+
+=item B<-l> (log)
+
+Log and print out the whole SMTP dialog.
+
+=item B<-r> (random address)
+
+Also try a reliably invalid address to catch hosts that try undermine
+address verification.
+
+=item B<-m> I<host> (MX to use)
+
+Force a connection to I<host> to check deliverability to that
+particular host irrespective of DNS entries. For example:
+
+ checkmail -m test.host.example user@domain.example
+
+=item B<-s> I<sender> (value for MAIL FROM)
+
+Override configuration and use I<sender> for MAIL FROM.
+
+=item B<-e> I<EHLO> (value for EHLO)
+
+Override configuration and use I<EHLO> for EHLO.
+
+=item B<-f> I<file> (file)
+
+Process all addresses from I<file> (one on each line).
+
+=back
+
+=head1 INSTALLATION
+
+Just copy checkmail to some directory and get started.
+
+You can run your first test with
+
+ checkmail user@example.org
+
+=head1 ENVIRONMENT
+
+See documentation of I<Net::DNS::Resolver>.
+
+=head1 FILES
+
+=over 4
+
+=item F<checkmail.pl>
+
+The script itself.
+
+=back
+
+=head1 BUGS
+
+Please report any bugs or feature request to the author or use the
+bug tracker at L<http://bugs.th-h.de/>!
+
+=head1 SEE ALSO
+
+L<http://th-h.de/download/scripts.php> will have the current
+version of this program.
+
+This program is maintained using the Git version control system. You
+may clone L<git://code.th-h.de/mail/checkmail.git> to check out the
+current development tree or browse it on the web via
+L<http://code.th-h.de/?p=mail/checkmail.git>.
+
+=head1 AUTHOR
+
+Thomas Hochstein <thh@thh.name>
+
+=head1 COPYRIGHT AND LICENSE
+
+Copyright (c) 2002-2016 Thomas Hochstein <thh@thh.name>
+
+This program is free software; you may redistribute it and/or modify it
+under the same terms as Perl itself.
+
+=cut
projects / mail / checkmail.git / blobdiff