SMIME.pm 6.07 KB
Newer Older
1
2
3
4
5
6
7
8
9
# -*- indent-tabs-mode: nil; -*-
# vim:ft=perl:et:sw=4
# $Id$

# Sympa - SYsteme de Multi-Postage Automatique
#
# Copyright (c) 1997, 1998, 1999 Institut Pasteur & Christophe Wolfhugel
# Copyright (c) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
# 2006, 2007, 2008, 2009, 2010, 2011 Comite Reseau des Universites
10
# Copyright (c) 2011, 2012, 2013, 2014, 2015 GIP RENATER
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
#
# 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, see <http://www.gnu.org/licenses/>.

package Sympa::Tools::SMIME;

use strict;
use warnings;
use English qw(-no_match_vars);

use Conf;
use Log;

=over

=item find_keys ( $that, $operation )

Find the appropriate S/MIME keys/certs for $operation of $that.

$operation can be:

=over

=item 'sign'

return the preferred signing key/cert

=item 'decrypt'

return a list of possible decryption keys/certs

=item 'encrypt'

return the preferred encryption key/cert

=back

Returnss C<($certs, $keys)>.
For 'sign' and 'encrypt', these are strings containing the absolute filename.
For 'decrypt', these are arrayrefs containing absolute filenames.

=back

=cut

# Old name: tools::smime_find_keys()
sub find_keys {
    Log::do_log('debug2', '(%s, %s)', @_);
    my $that = shift || '*';
    my $operation = shift;

    my $dir;
    if (ref $that eq 'Sympa::List') {
        $dir = $that->{'dir'};
    } else {
        $dir = $Conf::Conf{'home'} . '/sympa';    #FIXME
    }

    my (%certs, %keys);
    my $ext = ($operation eq 'sign' ? 'sign' : 'enc');

    unless (opendir(D, $dir)) {
        return undef;
    }

    while (my $fn = readdir(D)) {
        if ($fn =~ /^cert\.pem/) {
            $certs{"$dir/$fn"} = 1;
        } elsif ($fn =~ /^private_key/) {
            $keys{"$dir/$fn"} = 1;
        }
    }
    closedir(D);

    foreach my $c (keys %certs) {
        my $k = $c;
        $k =~ s/\/cert\.pem/\/private_key/;
        unless ($keys{$k}) {
            Log::do_log('debug3', '%s exists, but matching %s doesn\'t',
                $c, $k);
            delete $certs{$c};
        }
    }

    foreach my $k (keys %keys) {
        my $c = $k;
        $c =~ s/\/private_key/\/cert\.pem/;
        unless ($certs{$c}) {
            Log::do_log('debug3', '%s exists, but matching %s doesn\'t',
                $k, $c);
            delete $keys{$k};
        }
    }

    my ($certs, $keys);
    if ($operation eq 'decrypt') {
        $certs = [sort keys %certs];
        $keys  = [sort keys %keys];
    } else {
        if ($certs{"$dir/cert.pem.$ext"}) {
            $certs = "$dir/cert.pem.$ext";
            $keys  = "$dir/private_key.$ext";
        } elsif ($certs{"$dir/cert.pem"}) {
            $certs = "$dir/cert.pem";
            $keys  = "$dir/private_key";
        } else {
            Log::do_log('debug3', '%s: no certs/keys found for %s',
                $that, $operation);
            return undef;
        }
    }

    Log::do_log('debug3', '%s: certs/keys for %s found', $that, $operation);
    return ($certs, $keys);
}

BEGIN { eval 'use Crypt::OpenSSL::X509'; }

# IN: hashref:
# file => filename
# text => PEM-encoded cert
# OUT: hashref
# email => email address from cert
# subject => distinguished name
# purpose => hashref
#  enc => true if v3 purpose is encryption
#  sign => true if v3 purpose is signing
#
# Old name: tools::smime_parse_cert()
sub parse_cert {
    Log::do_log('debug3', '(%s => %s)', @_);
    my %arg = @_;

    ## Load certificate
    my $x509;
    if ($arg{'text'}) {
        $x509 = eval { Crypt::OpenSSL::X509->new_from_string($arg{'text'}) };
    } elsif ($arg{'file'}) {
        $x509 = eval { Crypt::OpenSSL::X509->new_from_file($arg{'file'}) };
    } else {
        Log::do_log('err', 'Neither "text" nor "file" given');
        return undef;
    }
    unless ($x509) {
        Log::do_log('err', 'Cannot parse certificate');
        return undef;
    }

    my %res;
    $res{subject} = join '',
        map { '/' . $_->as_string } @{$x509->subject_name->entries};
172
173
174
175
176
	my $extensions = $x509->extensions_by_name();
	my %emails;
	foreach my $extension_name (keys %$extensions) {
		if ($extension_name eq 'subjectAltName') {
			my $extension_value = $extensions->{$extension_name}->value();
177
			my @addresses = split '\.{2,}', $extension_value;
178
179
180
181
182
183
184
185
186
187
188
189
190
			shift @addresses;
			foreach my $address (@addresses) {
				$emails{$address} = 1;
			}
		}
	}
	if (%emails) {
		foreach my $email (keys %emails) {
			$res{email}{lc($email)} =1;
		}
	}elsif($x509->email) {
		$res{email}{lc($x509->email)} = 1;
	}
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
    # Check key usage roughy.
    my %purposes = $x509->extensions_by_name->{keyUsage}->hash_bit_string;
    $res{purpose}->{sign} = $purposes{'Digital Signature'} ? 1 : '';
    $res{purpose}->{enc}  = $purposes{'Key Encipherment'}  ? 1 : '';
    return \%res;
}

# NO LONGER USED
# However, this function may be useful because it can extract messages openssl
# can not (e.g. signature part not encoded by BASE64).
sub smime_extract_certs {
    my ($mime, $outfile) = @_;
    Log::do_log('debug2', '(%s)', $mime->mime_type);

    if ($mime->mime_type =~ /application\/(x-)?pkcs7-/) {
        my $pipeout;
        unless (
            open $pipeout,
            '|-', $Conf::Conf{openssl}, 'pkcs7', '-print_certs',
            '-inform' => 'der',
            '-out'    => $outfile
            ) {
            Log::do_log('err', 'Unable to run openssl pkcs7: %m');
            return 0;
        }
        print $pipeout $mime->bodyhandle->as_string;
        close $pipeout;
        my $status = $CHILD_ERROR >> 8;
        if ($status) {
            Log::do_log('err', 'Openssl pkcs7 returned an error: %s',
                $status);
            return 0;
        }
        return 1;
    }
}

1;