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
179
180
181
182
183
184
185
186
187
188
189
190
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
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
|
/* verify.c - Verify signatures
* Copyright (C) 2001, 2002, 2003, 2007, 2008, 2010 Free Software
* Foundation, Inc.
*
* Author: Timo Schulz
*
* This file is part of OpenCDK.
*
* The OpenCDK library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA
*
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include "opencdk.h"
#include "main.h"
#include "filters.h"
#include "packet.h"
/* Table of all supported digest algorithms and their names. */
struct
{
const char *name;
int algo;
} digest_table[] =
{
{
"MD5", GNUTLS_DIG_MD5},
{
"SHA1", GNUTLS_DIG_SHA1},
{
"RIPEMD160", GNUTLS_DIG_RMD160},
{
"SHA256", GNUTLS_DIG_SHA256},
{
"SHA384", GNUTLS_DIG_SHA384},
{
"SHA512", GNUTLS_DIG_SHA512},
{
NULL, 0}
};
static cdk_error_t file_verify_clearsign (cdk_ctx_t, const char *,
const char *);
/**
* cdk_stream_verify:
* @hd: session handle
* @inp: the input stream
* @data: for detached signatures, this is the data stream @inp is the sig
* @out: where the output shall be written.
*
* Verify a signature in stream.
*/
cdk_error_t
cdk_stream_verify (cdk_ctx_t hd, cdk_stream_t inp, cdk_stream_t data,
cdk_stream_t out)
{
/* FIXME: out is not currently used. */
if (cdk_armor_filter_use (inp))
cdk_stream_set_armor_flag (inp, 0);
return _cdk_proc_packets (hd, inp, data, NULL, NULL, NULL);
}
/**
* cdk_file_verify:
* @hd: the session handle
* @file: the input file
* @data_file: for detached signature this is the data file and @file is the sig.
* @output: the output file
*
* Verify a signature.
**/
cdk_error_t
cdk_file_verify (cdk_ctx_t hd, const char *file, const char *data_file,
const char *output)
{
struct stat stbuf;
cdk_stream_t inp, data;
char buf[4096];
int n;
cdk_error_t rc;
if (!hd || !file)
return CDK_Inv_Value;
if (output && !hd->opt.overwrite && !stat (output, &stbuf))
return CDK_Inv_Mode;
rc = cdk_stream_open (file, &inp);
if (rc)
return rc;
if (cdk_armor_filter_use (inp))
{
n = cdk_stream_peek (inp, (byte *) buf, DIM (buf) - 1);
if (!n || n == -1)
return CDK_EOF;
buf[n] = '\0';
if (strstr (buf, "BEGIN PGP SIGNED MESSAGE"))
{
cdk_stream_close (inp);
return file_verify_clearsign (hd, file, output);
}
cdk_stream_set_armor_flag (inp, 0);
}
if (data_file)
{
rc = cdk_stream_open (data_file, &data);
if (rc)
{
cdk_stream_close (inp);
return rc;
}
}
else
data = NULL;
rc = _cdk_proc_packets (hd, inp, data, NULL, NULL, NULL);
if (data != NULL)
cdk_stream_close (data);
cdk_stream_close (inp);
return rc;
}
void
_cdk_result_verify_free (cdk_verify_result_t res)
{
if (!res)
return;
cdk_free (res->policy_url);
cdk_free (res->sig_data);
cdk_free (res);
}
cdk_verify_result_t
_cdk_result_verify_new (void)
{
cdk_verify_result_t res;
res = cdk_calloc (1, sizeof *res);
if (!res)
return NULL;
return res;
}
static cdk_error_t
file_verify_clearsign (cdk_ctx_t hd, const char *file, const char *output)
{
cdk_stream_t inp = NULL, out = NULL, tmp = NULL;
digest_hd_st md;
char buf[512], chk[512];
const char *s;
int i, is_signed = 0, nbytes;
int digest_algo = 0;
int err;
cdk_error_t rc;
if (output)
{
rc = cdk_stream_create (output, &out);
if (rc)
return rc;
}
rc = cdk_stream_open (file, &inp);
if (rc)
{
if (output)
cdk_stream_close (out);
return rc;
}
s = "-----BEGIN PGP SIGNED MESSAGE-----";
while (!cdk_stream_eof (inp))
{
nbytes = _cdk_stream_gets (inp, buf, DIM (buf) - 1);
if (!nbytes || nbytes == -1)
break;
if (!strncmp (buf, s, strlen (s)))
{
is_signed = 1;
break;
}
}
if (cdk_stream_eof (inp) && !is_signed)
{
rc = CDK_Armor_Error;
goto leave;
}
while (!cdk_stream_eof (inp))
{
nbytes = _cdk_stream_gets (inp, buf, DIM (buf) - 1);
if (!nbytes || nbytes == -1)
break;
if (nbytes == 1) /* Empty line */
break;
else if (!strncmp (buf, "Hash: ", 6))
{
for (i = 0; digest_table[i].name; i++)
{
if (!strcmp (buf + 6, digest_table[i].name))
{
digest_algo = digest_table[i].algo;
break;
}
}
}
}
if (digest_algo && _gnutls_hash_get_algo_len (digest_algo) <= 0)
{
rc = CDK_Inv_Algo;
goto leave;
}
if (!digest_algo)
digest_algo = GNUTLS_DIG_MD5;
err = _gnutls_hash_init (&md, digest_algo);
if (err < 0)
{
rc = map_gnutls_error (err);
goto leave;
}
s = "-----BEGIN PGP SIGNATURE-----";
while (!cdk_stream_eof (inp))
{
nbytes = _cdk_stream_gets (inp, buf, DIM (buf) - 1);
if (!nbytes || nbytes == -1)
break;
if (!strncmp (buf, s, strlen (s)))
break;
else
{
cdk_stream_peek (inp, (byte *) chk, DIM (chk) - 1);
i = strncmp (chk, s, strlen (s));
if (strlen (buf) == 0 && i == 0)
continue; /* skip last '\n' */
_cdk_trim_string (buf, i == 0 ? 0 : 1);
_gnutls_hash (&md, buf, strlen (buf));
}
if (!strncmp (buf, "- ", 2)) /* FIXME: handle it recursive. */
memmove (buf, buf + 2, nbytes - 2);
if (out)
{
if (strstr (buf, "\r\n"))
buf[strlen (buf) - 2] = '\0';
cdk_stream_write (out, buf, strlen (buf));
_cdk_stream_puts (out, _cdk_armor_get_lineend ());
}
}
/* We create a temporary stream object to store the
signature data in there. */
rc = cdk_stream_tmp_new (&tmp);
if (rc)
goto leave;
s = "-----BEGIN PGP SIGNATURE-----\n";
_cdk_stream_puts (tmp, s);
while (!cdk_stream_eof (inp))
{
nbytes = _cdk_stream_gets (inp, buf, DIM (buf) - 1);
if (!nbytes || nbytes == -1)
break;
if (nbytes < (int) (DIM (buf) - 3))
{
buf[nbytes - 1] = '\n';
buf[nbytes] = '\0';
}
cdk_stream_write (tmp, buf, nbytes);
}
/* FIXME: This code is not very elegant. */
cdk_stream_tmp_set_mode (tmp, STREAMCTL_READ);
cdk_stream_seek (tmp, 0);
cdk_stream_set_armor_flag (tmp, 0);
cdk_stream_read (tmp, NULL, 0);
/* the digest handle will be closed there. */
rc = _cdk_proc_packets (hd, tmp, NULL, NULL, NULL, &md);
leave:
_gnutls_hash_deinit (&md, NULL);
cdk_stream_close (out);
cdk_stream_close (tmp);
cdk_stream_close (inp);
return rc;
}
|