This file is indexed.

/usr/bin/dkimproxy-sign is in libmail-dkim-perl 0.44-1.

This file is owned by root:root, with mode 0o755.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
#!/usr/bin/perl -I../lib
#
# Copyright (c) 2005-2007 Messiah College. This program is free software.
# You can redistribute it and/or modify it under the terms of the
# GNU Public License as found at http://www.fsf.org/copyleft/gpl.html.
#
# Written by Jason Long, jlong@messiah.edu.

use strict;
use warnings;

use Mail::DKIM::Signer;
use Mail::DKIM::TextWrap;
use Getopt::Long;
use Pod::Usage;

my $type = "dkim";
my $selector = "selector1";
my $algorithm = "rsa-sha1";
my $method = "simple";
my $domain; # undef => auto-select domain
my $expiration;
my $identity;
my $key_file = "private.key";
my $key_protocol;
my @extra_tag;
my $debug_canonicalization;
my $binary;
my $help;
GetOptions(
		"type=s" => \$type,
		"algorithm=s" => \$algorithm,
		"method=s" => \$method,
		"selector=s" => \$selector,
		"domain=s" => \$domain,
		"expiration=i" => \$expiration,
		"identity=s" => \$identity,
		"key=s" => \$key_file,
		"key-protocol=s" => \$key_protocol,
		"debug-canonicalization=s" => \$debug_canonicalization,
		"extra-tag=s" => \@extra_tag,
		"binary" => \$binary,
		"help|?" => \$help,
		)
	or pod2usage(2);
pod2usage(1) if $help;
pod2usage("Error: unrecognized argument(s)")
	unless (@ARGV == 0);

my $debugfh;
if (defined $debug_canonicalization)
{
	open $debugfh, ">", $debug_canonicalization
		or die "Error: cannot write $debug_canonicalization: $!\n";
}
if ($binary)
{
	binmode STDIN;
}

my $dkim = new Mail::DKIM::Signer(
		Policy => \&signer_policy,
		Algorithm => $algorithm,
		Method => $method,
		Selector => $selector,
		KeyFile => $key_file,
		Debug_Canonicalization => $debugfh,
		);

while (<STDIN>)
{
	unless ($binary)
	{
		chomp $_;
		s/\015?$/\015\012/s;
	}
	$dkim->PRINT($_);
}
$dkim->CLOSE;

if ($debugfh)
{
	close $debugfh;
	print STDERR "wrote canonicalized message to $debug_canonicalization\n";
}

print $dkim->signature->as_string . "\n";

sub signer_policy
{
	my $dkim = shift;

	use Mail::DKIM::DkSignature;

	$dkim->domain($domain || $dkim->message_sender->host);

	my $class = $type eq "domainkeys" ? "Mail::DKIM::DkSignature" :
			$type eq "dkim" ? "Mail::DKIM::Signature" :
				die "unknown signature type '$type'\n";
	my $sig = $class->new(
			Algorithm => $dkim->algorithm,
			Method => $dkim->method,
			Headers => $dkim->headers,
			Domain => $dkim->domain,
			Selector => $dkim->selector,
			defined($expiration) ? (Expiration => time() + $expiration) : (),
			defined($identity) ? (Identity => $identity) : (),
		);
	$sig->protocol($key_protocol) if defined $key_protocol;
	foreach my $extra (@extra_tag)
	{
		my ($n, $v) = split /=/, $extra, 2;
		$sig->set_tag($n, $v);
	}
	$dkim->add_signature($sig);
	return;
}

__END__

=head1 NAME

dkimsign.pl - computes a DKIM signature for an email message

=head1 SYNOPSIS

  dkimsign.pl [options] < original_email.txt
    options:
      --type=TYPE
      --method=METHOD
      --selector=SELECTOR
      --expiration=INTEGER
      --debug-canonicalization=FILE

  dkimsign.pl --help
    to see a full description of the various options

=head1 OPTIONS

=over

=item B<--expiration>

Optional. Specify the desired signature expiration, as a delta
from the signature timestamp.

=item B<--type>

Determines the desired signature. Use dkim for a DKIM-Signature, or
domainkeys for a DomainKey-Signature.

=item B<--method>

Determines the desired canonicalization method. Possible values are
simple, simple/simple, simple/relaxed, relaxed, relaxed/relaxed,
relaxed/simple.

=item B<--debug-canonicalization>

Outputs the canonicalized message to the specified file, in addition
to computing the DKIM signature. This is helpful for debugging
canonicalization methods.

=back

=head1 AUTHOR

Jason Long, E<lt>jlong@messiah.eduE<gt>

=head1 COPYRIGHT AND LICENSE

Copyright (C) 2006-2007 by Messiah College

This program is free software; you can redistribute it and/or modify
it under the same terms as Perl itself, either Perl version 5.8.6 or,
at your option, any later version of Perl 5 you may have available.

=cut