Subversion Repositories

?revision_form?Rev ?revision_input??revision_submit??revision_endform?

Go to most recent revision | Details | Last modification | View Log | RSS feed

Rev Author Line No. Line
1 magnus 1
package DebPool::GnuPG;
2
 
3
###
4
#
5
# DebPool::GnuPG - Module for all interactions with GNU Privacy Guard
6
#
7
# Copyright 2003-2004 Joel Aelwyn. All rights reserved.
8
# 
9
# Redistribution and use in source and binary forms, with or without
10
# modification, are permitted provided that the following conditions
11
# are met:
12
# 1. Redistributions of source code must retain the above copyright
13
#    notice, this list of conditions and the following disclaimer.
14
# 2. Redistributions in binary form must reproduce the above copyright
15
#    notice, this list of conditions and the following disclaimer in the
16
#    documentation and/or other materials provided with the distribution.
17
# 3. Neither the name of the Author nor the names of any contributors
18
#    may be used to endorse or promote products derived from this software
19
#    without specific prior written permission.
20
# 
21
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24
# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31
# SUCH DAMAGE.
32
#
33
# $Id: GnuPG.pm 46 2005-02-12 17:52:37Z joel $
34
#
35
###
36
 
37
# We use 'our', so we must have at least Perl 5.6
38
 
39
require 5.006_000;
40
 
41
# Always good ideas.
42
 
43
use strict;
44
use warnings;
45
 
46
use POSIX; # WEXITSTATUS
47
use File::Temp qw(tempfile);
48
 
49
# We need these for open2()
50
 
51
use Fcntl;
52
use IPC::Open2;
53
 
54
### Module setup
55
 
56
BEGIN {
57
    use Exporter ();
58
    our ($VERSION, @ISA, @EXPORT, @EXPORT_OK, %EXPORT_TAGS);
59
 
60
    # Version checking
61
    $VERSION = '0.1.5';
62
 
63
    @ISA = qw(Exporter);
64
 
65
    @EXPORT = qw(
66
    );
67
 
68
    @EXPORT_OK = qw(
69
        &Check_Signature
70
        &Sign_Release
71
        &Strip_GPG
72
    );
73
 
74
    %EXPORT_TAGS = (
75
        'functions' => [qw(&Check_Signature &Sign_Release &Strip_GPG)],
76
        'vars' => [qw()],
77
    );
78
}
79
 
80
### Exported package globals
81
 
82
### Non-exported package globals
83
 
84
# Thread-safe? What's that? Package global error value. We don't export
85
# this directly, because it would conflict with other modules.
86
 
87
our($Error);
88
 
89
### File lexicals
90
 
91
# None
92
 
93
### Constant functions
94
 
95
# None
96
 
97
### Meaningful functions
98
 
99
# Check_Signature($file, $signature)
100
#
101
# Checks the GPG signature of $file (using $signature as an external
102
# signature file, if it is defined; if it isn't, $file is assumed to have
103
# an internal signature). Returns 0 on failure, 1 on success.
104
 
105
sub Check_Signature {
106
    use DebPool::Config qw(:vars);
107
    use DebPool::Logging qw(:functions :facility :level);
108
 
109
    my($file, $signature) = @_;
110
 
111
    my(@args) = ("--homedir=$Options{'gpg_home'}");
112
    push (@args, '--no-default-keyring', '--logger-fd=1');
113
 
114
    my($keyring);
115
 
116
    foreach $keyring (@{$Options{'gpg_keyrings'}}) {
117
        push(@args, "--keyring=$keyring");
118
    }
119
 
120
    push(@args, '--verify');
121
 
122
    if (defined($signature)) {
123
        push(@args, $signature);
124
    }
125
 
126
    push(@args, $file);
127
 
128
    my($pid) = IPC::Open2::open2(*GPG_IN, *GPG_OUT, $Options{'gpg_bin'}, @args);
129
    close(GPG_IN); # No input
130
    close(GPG_OUT); # Don't care about output, really, either
131
 
132
    waitpid($pid,0); # No flags, just wait.
133
    my($sysret) = WEXITSTATUS($?);
134
 
135
    if (0 != $sysret) { # Failure
136
        my($msg) = "Failed signature check on '$file' ";
137
        if (defined($signature)) {
138
            $msg .= "(signature file '$signature')";
139
        } else {
140
            $msg .= "(internal signature)";
141
        }
142
        Log_Message($msg, LOG_GPG, LOG_WARNING);
143
 
144
        return 0;
145
    }
146
 
147
    return 1;
148
}
149
 
150
# Sign_Release($release_file)
151
#
152
# Generates a detached GPG signature file for $release_file, and returns
153
# the filename. Returns undef, if an error occurs (and sets $Error).
154
 
155
sub Sign_Release {
156
    use DebPool::Config;
157
    use DebPool::Logging qw(:functions :facility :level);
158
 
159
    my($release_file) = @_;
160
 
161
    # Check that we have everything we need
162
 
163
    if (!defined($Options{'gpg_sign_key'})) {
164
        $Error = "No GPG signature key enabled";
165
        return undef;
166
    }
167
 
168
    if (!defined($Options{'gpg_passfile'})) {
169
        $Error = "No GPG passphrase file enabled";
170
        return undef;
171
    }
172
 
173
    # Open a secure tempfile to write the signature to
174
 
175
    my($tmpfile_handle, $tmpfile_name) = tempfile();
176
 
177
    # Open the Release file and grab the data from it
178
 
179
    if (!open(RELEASE, '<', $release_file)) {
180
        $Error = "Couldn't open Release file '$release_file': $!";
181
        return undef;
182
    }
183
    my(@release_text) = <RELEASE>;
184
    close(RELEASE);
185
 
186
    # Open the passphrase file and grab the data from it
187
 
188
    if (!open(PASS, '<', $Options{'gpg_passfile'})) {
189
        $Error = "Couldn't open passphrase file '$Options{'gpg_passfile'}': $!";
190
        return undef;
191
    }
192
    my($passphrase) = <PASS>; # This is only safe because we don't care.
193
    close(PASS);
194
 
195
    # We are go for main engine start
196
 
197
    my(@args) = ("--homedir=$Options{'gpg_home'}");
198
    push(@args, "--default-key=$Options{'gpg_sign_key'}");
199
    push(@args, '--passphrase-fd=0', '--batch', '--no-tty', '--detach-sign');
200
    push(@args, '--armor', '--output=-');
201
 
202
    my($gnupg_pid) = IPC::Open2::open2(*GPG_IN, *GPG_OUT, $Options{'gpg_bin'}, @args);
203
 
204
    my($child_pid);
205
    my(@signature);
206
    if ($child_pid = fork) { # In the parent
207
        # Close filehandles used by the child.
208
 
209
        close(GPG_IN);
210
        close($tmpfile_handle);
211
 
212
        # Send all the data to GnuPG
213
 
214
        print GPG_OUT $passphrase;
215
        print GPG_OUT @release_text;
216
        close(GPG_OUT);
217
 
218
        waitpid($child_pid, 0);
219
    } else { # In the child - we hope
220
        if (!defined($child_pid)) {
221
            die "Couldn't fork: $!\n";
222
        }
223
 
224
        # Close filehandle used by the parent.
225
 
226
        close(GPG_OUT);
227
 
228
        # And read back the results
229
 
230
        @signature = <GPG_IN>;
231
        close(GPG_IN);
232
 
233
        # Finally, print the results to the tempfile
234
 
235
        print $tmpfile_handle @signature;
236
        close($tmpfile_handle);
237
 
238
        exit(0);
239
    }
240
 
241
 
242
    # And we're done
243
 
244
    return $tmpfile_name;
245
}
246
 
247
# Strip_GPG(@text)
248
#
249
# Goes through @text and determine if it has GnuPG headers; if so, strip
250
# out the headers, and undo GnuPG's header protection ('^-' -> '^-- -').
251
 
252
sub Strip_GPG {
253
    my(@text) = @_;
254
 
255
    my($count);
256
    my($header, $firstblank, $sigstart, $sigend);
257
 
258
    for $count (0..$#text) {
259
        if ($text[$count] =~ m/^-----BEGIN PGP SIGNED MESSAGE-----$/) {
260
            $header = $count;
261
        } elsif (!defined($firstblank) && $text[$count] =~ m/^$/) {
262
            $firstblank = $count;
263
        } elsif ($text[$count] =~ m/^-----BEGIN PGP SIGNATURE-----$/) {
264
            $sigstart = $count;
265
        } elsif ($text[$count] =~ m/^-----END PGP SIGNATURE-----$/) {
266
            $sigend = $count;
267
        }
268
    }
269
 
270
    # If we didn't find all three parts, it isn't a validly signed message
271
    # (or it's externally signed, but that might as well be the same
272
    # thing for our purposes - there's nothing to remove).
273
 
274
    if (!defined($header) || !defined($sigstart) || !defined($sigend)) {
275
        return @text;
276
    }
277
 
278
    # Okay. Back to front, so that we don't muck up reference numbers.
279
    # First, we rip out the signature data by splicing it with an empty
280
    # list.
281
 
282
    splice(@text, $sigstart, ($sigend - $sigstart) + 1);
283
 
284
    # We used to just rip off the first 3 lines (BEGIN line, hash header,
285
    # and a blank line). However, this was a cheap shortcut that broke as
286
    # of GnuPG 1.0.7, because it relied on there being exactly one GnuPG
287
    # header line.
288
    #
289
    # Now, we rip out everything from the header line to the first blank,
290
    # which should always be correct.
291
 
292
    splice(@text, $header, ($firstblank - $header) + 1);
293
 
294
    # All done. Fire it back.
295
 
296
    return @text;
297
}
298
 
299
END {}
300
 
301
1;
302
 
303
__END__
304
 
305
# vim:set tabstop=4 expandtab: