aboutsummaryrefslogtreecommitdiff
path: root/src/util/gnunet-ecc.c
blob: 02d2020addc9692bdc6d00ade4f50547d8800b78 (plain) (blame)
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
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
/*
     This file is part of GNUnet.
     Copyright (C) 2012, 2013 GNUnet e.V.

     GNUnet is free software: you can redistribute it and/or modify it
     under the terms of the GNU Affero General Public License as published
     by the Free Software Foundation, either version 3 of the License,
     or (at your option) any later version.

     GNUnet 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
     Affero General Public License for more details.

     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.

     SPDX-License-Identifier: AGPL3.0-or-later
 */

/**
 * @file util/gnunet-ecc.c
 * @brief tool to manipulate EDDSA key files
 * @author Christian Grothoff
 */
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_testing_lib.h"
#include <gcrypt.h>

/**
 * Number of characters a Base32-encoded public key requires.
 */
#define KEY_STR_LEN sizeof(struct GNUNET_CRYPTO_EddsaPublicKey) * 8 / 5 + 1

/**
 * Flag for listing public key.
 */
static int list_keys;

/**
 * Flag for listing public key.
 */
static unsigned int list_keys_count;

/**
 * Flag for printing public key.
 */
static int print_public_key;

/**
 * Flag for printing private key.
 */
static int print_private_key;

/**
 * Flag for printing public key in hex.
 */
static int print_public_key_hex;

/**
 * Flag for printing the output of random example operations.
 */
static int print_examples_flag;

/**
 * Option set to create a bunch of keys at once.
 */
static unsigned int make_keys;


/**
 * Create a flat file with a large number of key pairs for testing.
 *
 * @param fn File name to store the keys.
 * @param prefix Desired prefix for the public keys, NULL if any key is OK.
 */
static void
create_keys (const char *fn, const char *prefix)
{
  FILE *f;
  struct GNUNET_CRYPTO_EddsaPrivateKey *pk;
  struct GNUNET_CRYPTO_EddsaPublicKey target_pub;
  static char vanity[KEY_STR_LEN + 1];
  size_t len;
  size_t n;
  size_t rest;
  unsigned char mask;
  unsigned target_byte;
  char *s;

  if (NULL == (f = fopen (fn, "w+")))
  {
    fprintf (stderr, _ ("Failed to open `%s': %s\n"), fn, strerror (errno));
    return;
  }
  if (NULL != prefix)
  {
    len = GNUNET_strlcpy (vanity, prefix, sizeof(vanity));
    n = len * 5 / 8;
    rest = len * 5 % 8;

    memset (&vanity[len], '0', KEY_STR_LEN - len);
    vanity[KEY_STR_LEN] = '\0';
    GNUNET_assert (GNUNET_OK ==
                   GNUNET_CRYPTO_eddsa_public_key_from_string (vanity,
                                                               KEY_STR_LEN,
                                                               &target_pub));
    if (0 != rest)
    {
      /**
       * Documentation by example:
       * vanity = "A"
       * len = 1
       * n = 5/8 = 0 (bytes)
       * rest = 5%8 = 5 (bits)
       * mask = ~(2**(8 - 5) - 1) = ~(2**3 - 1) = ~(8 - 1) = ~b111 = b11111000
       */mask = ~((int) pow (2, 8 - rest) - 1);
      target_byte = ((unsigned char *) &target_pub)[n] & mask;
    }
    else
    {
      /* Just so old (debian) versions of GCC calm down with the warnings. */
      mask = target_byte = 0;
    }
    s = GNUNET_CRYPTO_eddsa_public_key_to_string (&target_pub);
    fprintf (stderr,
             _ ("Generating %u keys like %s, please wait"),
             make_keys,
             s);
    GNUNET_free (s);
    fprintf (stderr, "\nattempt %s [%u, %X]\n", vanity, (unsigned int) n, mask);
  }
  else
  {
    fprintf (stderr, _ ("Generating %u keys, please wait"), make_keys);
    /* Just so old (debian) versions of GCC calm down with the warnings. */
    n = rest = target_byte = mask = 0;
  }

  while (0 < make_keys--)
  {
    fprintf (stderr, ".");
    if (NULL == (pk = GNUNET_CRYPTO_eddsa_key_create ()))
    {
      GNUNET_break (0);
      break;
    }
    if (NULL != prefix)
    {
      struct GNUNET_CRYPTO_EddsaPublicKey newkey;

      GNUNET_CRYPTO_eddsa_key_get_public (pk, &newkey);
      if (0 != memcmp (&target_pub, &newkey, n))
      {
        make_keys++;
        continue;
      }
      if (0 != rest)
      {
        unsigned char new_byte;

        new_byte = ((unsigned char *) &newkey)[n] & mask;
        if (target_byte != new_byte)
        {
          make_keys++;
          continue;
        }
      }
    }
    if (GNUNET_TESTING_HOSTKEYFILESIZE !=
        fwrite (pk, 1, GNUNET_TESTING_HOSTKEYFILESIZE, f))
    {
      fprintf (stderr,
               _ ("\nFailed to write to `%s': %s\n"),
               fn,
               strerror (errno));
      GNUNET_free (pk);
      break;
    }
    GNUNET_free (pk);
  }
  if (UINT_MAX == make_keys)
    fprintf (stderr, _ ("\nFinished!\n"));
  else
    fprintf (stderr, _ ("\nError, %u keys not generated\n"), make_keys);
  fclose (f);
}


static void
print_hex (const char *msg, const void *buf, size_t size)
{
  printf ("%s: ", msg);
  for (size_t i = 0; i < size; i++)
  {
    printf ("%02hhx", ((const uint8_t *) buf)[i]);
  }
  printf ("\n");
}


static void
print_examples_ecdh ()
{
  struct GNUNET_CRYPTO_EcdhePrivateKey *dh_priv1;
  struct GNUNET_CRYPTO_EcdhePublicKey *dh_pub1;
  struct GNUNET_CRYPTO_EcdhePrivateKey *dh_priv2;
  struct GNUNET_CRYPTO_EcdhePublicKey *dh_pub2;
  struct GNUNET_HashCode hash;
  char buf[128];

  dh_pub1 = GNUNET_new (struct GNUNET_CRYPTO_EcdhePublicKey);
  dh_priv1 = GNUNET_CRYPTO_ecdhe_key_create ();
  dh_pub2 = GNUNET_new (struct GNUNET_CRYPTO_EcdhePublicKey);
  dh_priv2 = GNUNET_CRYPTO_ecdhe_key_create ();
  GNUNET_CRYPTO_ecdhe_key_get_public (dh_priv1, dh_pub1);
  GNUNET_CRYPTO_ecdhe_key_get_public (dh_priv2, dh_pub2);

  GNUNET_assert (NULL !=
                 GNUNET_STRINGS_data_to_string (dh_priv1, 32, buf, 128));
  printf ("ECDHE key 1:\n");
  printf ("private: %s\n", buf);
  print_hex ("private(hex)", dh_priv1, sizeof *dh_priv1);
  GNUNET_assert (NULL != GNUNET_STRINGS_data_to_string (dh_pub1, 32, buf, 128));
  printf ("public: %s\n", buf);
  print_hex ("public(hex)", dh_pub1, sizeof *dh_pub1);

  GNUNET_assert (NULL !=
                 GNUNET_STRINGS_data_to_string (dh_priv2, 32, buf, 128));
  printf ("ECDHE key 2:\n");
  printf ("private: %s\n", buf);
  print_hex ("private(hex)", dh_priv2, sizeof *dh_priv2);
  GNUNET_assert (NULL != GNUNET_STRINGS_data_to_string (dh_pub2, 32, buf, 128));
  printf ("public: %s\n", buf);
  print_hex ("public(hex)", dh_pub2, sizeof *dh_pub2);

  GNUNET_assert (GNUNET_OK ==
                 GNUNET_CRYPTO_ecc_ecdh (dh_priv1, dh_pub2, &hash));
  GNUNET_assert (NULL != GNUNET_STRINGS_data_to_string (&hash, 64, buf, 128));
  printf ("ECDH shared secret: %s\n", buf);

  GNUNET_free (dh_priv1);
  GNUNET_free (dh_priv2);
  GNUNET_free (dh_pub1);
  GNUNET_free (dh_pub2);
}


/**
 * Print some random example operations to stdout.
 */
static void
print_examples ()
{
  print_examples_ecdh ();
  // print_examples_ecdsa ();
  // print_examples_eddsa ();
}


static void
print_key (const char *filename)
{
  struct GNUNET_DISK_FileHandle *fd;
  struct GNUNET_CRYPTO_EddsaPrivateKey private_key;
  struct GNUNET_CRYPTO_EddsaPublicKey public_key;
  char *hostkeys_data;
  char *hostkey_str;
  uint64_t fs;
  unsigned int total_hostkeys;
  unsigned int c;
  ssize_t sret;

  if (GNUNET_YES != GNUNET_DISK_file_test (filename))
  {
    fprintf (stderr, _ ("Hostkeys file `%s' not found\n"), filename);
    return;
  }

  /* Check hostkey file size, read entire thing into memory */
  if (GNUNET_OK !=
      GNUNET_DISK_file_size (filename, &fs, GNUNET_YES, GNUNET_YES))
    fs = 0;
  if (0 == fs)
  {
    fprintf (stderr, _ ("Hostkeys file `%s' is empty\n"), filename);
    return;   /* File is empty */
  }
  if (0 != (fs % GNUNET_TESTING_HOSTKEYFILESIZE))
  {
    fprintf (stderr, _ ("Incorrect hostkey file format: %s\n"), filename);
    return;
  }
  fd = GNUNET_DISK_file_open (filename,
                              GNUNET_DISK_OPEN_READ,
                              GNUNET_DISK_PERM_NONE);
  if (NULL == fd)
  {
    GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR, "open", filename);
    return;
  }
  hostkeys_data = GNUNET_malloc (fs);
  sret = GNUNET_DISK_file_read (fd, hostkeys_data, fs);
  if ((sret < 0) || (fs != (size_t) sret))
  {
    fprintf (stderr, _ ("Could not read hostkey file: %s\n"), filename);
    GNUNET_free (hostkeys_data);
    GNUNET_DISK_file_close (fd);
    return;
  }
  GNUNET_DISK_file_close (fd);

  if (NULL == hostkeys_data)
    return;
  total_hostkeys = fs / GNUNET_TESTING_HOSTKEYFILESIZE;
  for (c = 0; (c < total_hostkeys) && (c < list_keys_count); c++)
  {
    GNUNET_memcpy (&private_key,
                   hostkeys_data + (c * GNUNET_TESTING_HOSTKEYFILESIZE),
                   GNUNET_TESTING_HOSTKEYFILESIZE);
    GNUNET_CRYPTO_eddsa_key_get_public (&private_key, &public_key);
    hostkey_str = GNUNET_CRYPTO_eddsa_public_key_to_string (&public_key);
    if (NULL != hostkey_str)
    {
      fprintf (stderr, "%4u: %s\n", c, hostkey_str);
      GNUNET_free (hostkey_str);
    }
    else
      fprintf (stderr, "%4u: %s\n", c, "invalid");
  }
  GNUNET_free (hostkeys_data);
}


/**
 * Main function that will be run by the scheduler.
 *
 * @param cls closure, NULL
 * @param args remaining command-line arguments
 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
 * @param cfg configuration
 */
static void
run (void *cls,
     char *const *args,
     const char *cfgfile,
     const struct GNUNET_CONFIGURATION_Handle *cfg)
{
  (void) cls;
  (void) cfgfile;
  (void) cfg;

  if (print_examples_flag)
  {
    print_examples ();
    return;
  }
  if (NULL == args[0])
  {
    fprintf (stderr, "%s", _ ("No hostkey file specified on command line\n"));
    return;
  }
  if (list_keys)
  {
    print_key (args[0]);
    return;
  }
  if (make_keys > 0)
  {
    create_keys (args[0], args[1]);
    return;
  }
  if (print_public_key || print_public_key_hex || print_private_key)
  {
    char *str;
    struct GNUNET_DISK_FileHandle *keyfile;
    struct GNUNET_CRYPTO_EddsaPrivateKey pk;
    struct GNUNET_CRYPTO_EddsaPublicKey pub;

    keyfile = GNUNET_DISK_file_open (args[0],
                                     GNUNET_DISK_OPEN_READ,
                                     GNUNET_DISK_PERM_NONE);
    if (NULL == keyfile)
      return;
    while (sizeof(pk) == GNUNET_DISK_file_read (keyfile, &pk, sizeof(pk)))
    {
      GNUNET_CRYPTO_eddsa_key_get_public (&pk, &pub);
      if (print_public_key_hex)
      {
        print_hex ("HEX:", &pub, sizeof(pub));
      }
      else if (print_public_key)
      {
        str = GNUNET_CRYPTO_eddsa_public_key_to_string (&pub);
        fprintf (stdout, "%s\n", str);
        GNUNET_free (str);
      }
      else if (print_private_key)
      {
        str = GNUNET_CRYPTO_eddsa_private_key_to_string (&pk);
        fprintf (stdout, "%s\n", str);
        GNUNET_free (str);
      }
    }
    GNUNET_DISK_file_close (keyfile);
  }
}


/**
 * Program to manipulate ECC key files.
 *
 * @param argc number of arguments from the command line
 * @param argv command line arguments
 * @return 0 ok, 1 on error
 */
int
main (int argc, char *const *argv)
{
  struct GNUNET_GETOPT_CommandLineOption options[] =
  { GNUNET_GETOPT_option_flag ('i',
                               "iterate",
                               gettext_noop (
                                 "list keys included in a file (for testing)"),
                               &list_keys),
    GNUNET_GETOPT_option_uint (
      'e',
      "end=",
      "COUNT",
      gettext_noop ("number of keys to list included in a file (for testing)"),
      &list_keys_count),
    GNUNET_GETOPT_option_uint (
      'g',
      "generate-keys",
      "COUNT",
      gettext_noop ("create COUNT public-private key pairs (for testing)"),
      &make_keys),
    GNUNET_GETOPT_option_flag ('p',
                               "print-public-key",
                               gettext_noop (
                                 "print the public key in ASCII format"),
                               &print_public_key),
    GNUNET_GETOPT_option_flag ('P',
                               "print-private-key",
                               gettext_noop (
                                 "print the private key in ASCII format"),
                               &print_private_key),
    GNUNET_GETOPT_option_flag ('x',
                               "print-hex",
                               gettext_noop (
                                 "print the public key in HEX format"),
                               &print_public_key_hex),
    GNUNET_GETOPT_option_flag (
      'E',
      "examples",
      gettext_noop (
        "print examples of ECC operations (used for compatibility testing)"),
      &print_examples_flag),
    GNUNET_GETOPT_OPTION_END };
  int ret;

  list_keys_count = UINT32_MAX;
  if (GNUNET_OK != GNUNET_STRINGS_get_utf8_args (argc, argv, &argc, &argv))
    return 2;

  ret = (GNUNET_OK ==
         GNUNET_PROGRAM_run (argc,
                             argv,
                             "gnunet-ecc [OPTIONS] keyfile [VANITY_PREFIX]",
                             gettext_noop (
                               "Manipulate GNUnet private ECC key files"),
                             options,
                             &run,
                             NULL))
        ? 0
        : 1;
  GNUNET_free ((void *) argv);
  return ret;
}


/* end of gnunet-ecc.c */