summaryrefslogtreecommitdiff
path: root/src/regex/plugin_block_regex.c
blob: ac9eee07cf6660f21aa422bc71f28f10025f9e62 (plain)
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
/*
     This file is part of GNUnet
     (C) 2013 Christian Grothoff (and other contributing authors)

     GNUnet 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 3, 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
     General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/

/**
 * @file regex/plugin_block_regex.c
 * @brief blocks used for regex storage and search
 * @author Bartlomiej Polot
 */

#include "platform.h"
#include "gnunet_block_plugin.h"
#include "block_regex.h"
#include "regex_block_lib.h"
#include "gnunet_constants.h"
#include "gnunet_signatures.h"


/**
 * Function called to validate a reply or a request of type
 * GNUNET_BLOCK_TYPE_REGEX.
 * For request evaluation, pass "NULL" for the reply_block.
 * Note that it is assumed that the reply has already been
 * matched to the key (and signatures checked) as it would
 * be done with the "get_key" function.
 *
 * @param cls closure
 * @param type block type
 * @param query original query (hash)
 * @param bf pointer to bloom filter associated with query; possibly updated (!)
 * @param bf_mutator mutation value for bf
 * @param xquery extrended query data (can be NULL, depending on type)
 * @param xquery_size number of bytes in xquery
 * @param reply_block response to validate
 * @param reply_block_size number of bytes in reply block
 * @return characterization of result
 */
static enum GNUNET_BLOCK_EvaluationResult
evaluate_block_regex (void *cls, enum GNUNET_BLOCK_Type type,
                      const struct GNUNET_HashCode *query,
                      struct GNUNET_CONTAINER_BloomFilter **bf,
                      int32_t bf_mutator, const void *xquery,
                      size_t xquery_size, const void *reply_block,
                      size_t reply_block_size)
{
  if (NULL == reply_block)
  {
    if (0 != xquery_size)
      {
        const char *s;

        s = (const char *) xquery;
        if ('\0' != s[xquery_size - 1]) /* must be valid 0-terminated string */
          {
            GNUNET_break_op (0);
            return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
          }
      }
    return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
  }
  if (0 != xquery_size)
  {
    const char *s;

    s = (const char *) xquery;
    if ('\0' != s[xquery_size - 1]) /* must be valid 0-terminated string */
    {
      GNUNET_break_op (0);
      return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
    }
  }
  else if (NULL != query)
  {
    /* xquery is required for regex GETs, at least an empty string */
    GNUNET_break_op (0);
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "type %d, query %p, xquery %p\n",
                type, query, xquery);
    return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
  }
  switch (REGEX_BLOCK_check (reply_block,
			     reply_block_size,
			     query,
			     xquery))
  {
    case GNUNET_SYSERR:
      GNUNET_break_op(0);
      return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
    case GNUNET_NO:
      /* xquery missmatch, can happen */
      return GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT;
    default:
      break;
  }
  if (NULL != bf)
  {
    struct GNUNET_HashCode chash;
    struct GNUNET_HashCode mhash;

    GNUNET_CRYPTO_hash (reply_block, reply_block_size, &chash);
    GNUNET_BLOCK_mingle_hash (&chash, bf_mutator, &mhash);
    if (NULL != *bf)
    {
      if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (*bf, &mhash))
        return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
    }
    else
    {
      *bf = GNUNET_CONTAINER_bloomfilter_init (NULL, 8, GNUNET_CONSTANTS_BLOOMFILTER_K);
    }
    GNUNET_CONTAINER_bloomfilter_add (*bf, &mhash);
  }
  return GNUNET_BLOCK_EVALUATION_OK_MORE;
}


/**
 * Function called to validate a reply or a request of type
 * GNUNET_BLOCK_TYPE_REGEX_ACCEPT.
 * For request evaluation, pass "NULL" for the reply_block.
 * Note that it is assumed that the reply has already been
 * matched to the key (and signatures checked) as it would
 * be done with the "get_key" function.
 *
 * @param cls closure
 * @param type block type
 * @param query original query (hash)
 * @param bf pointer to bloom filter associated with query; possibly updated (!)
 * @param bf_mutator mutation value for bf
 * @param xquery extrended query data (can be NULL, depending on type)
 * @param xquery_size number of bytes in xquery
 * @param reply_block response to validate
 * @param reply_block_size number of bytes in reply block
 * @return characterization of result
 */
static enum GNUNET_BLOCK_EvaluationResult
evaluate_block_regex_accept (void *cls, enum GNUNET_BLOCK_Type type,
                             const struct GNUNET_HashCode * query,
                             struct GNUNET_CONTAINER_BloomFilter **bf,
                             int32_t bf_mutator, const void *xquery,
                             size_t xquery_size, const void *reply_block,
                             size_t reply_block_size)
{
  const struct RegexAcceptBlock *rba;

  if (0 != xquery_size)
  {
    GNUNET_break_op (0);
    return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
  }
  if (NULL == reply_block)
    return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
  if (sizeof (struct RegexAcceptBlock) != reply_block_size)
  {
    GNUNET_break_op(0);
    return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
  }
  rba = reply_block;
  if (ntohl (rba->purpose.size) !=
      sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
      sizeof (struct GNUNET_TIME_AbsoluteNBO) +
      sizeof (struct GNUNET_HashCode))
  {
    GNUNET_break_op(0);
    return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
  }
  if (0 == GNUNET_TIME_absolute_get_remaining (GNUNET_TIME_absolute_ntoh (rba->expiration_time)).rel_value_us)
  {
    /* technically invalid, but can happen without an error, so
       we're nice by reporting it as a 'duplicate' */
    return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
  }
  if (GNUNET_OK !=
      GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_REGEX_ACCEPT,
				&rba->purpose,
				&rba->signature,
				&rba->peer.public_key))
  {
    GNUNET_break_op(0);
    return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
  }
  if (NULL != bf)
  {
    struct GNUNET_HashCode chash;
    struct GNUNET_HashCode mhash;

    GNUNET_CRYPTO_hash (reply_block, reply_block_size, &chash);
    GNUNET_BLOCK_mingle_hash (&chash, bf_mutator, &mhash);
    if (NULL != *bf)
    {
      if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (*bf, &mhash))
        return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
    }
    else
    {
      *bf = GNUNET_CONTAINER_bloomfilter_init (NULL, 8, GNUNET_CONSTANTS_BLOOMFILTER_K);
    }
    GNUNET_CONTAINER_bloomfilter_add (*bf, &mhash);
  }
  return GNUNET_BLOCK_EVALUATION_OK_MORE;
}


/**
 * Function called to validate a reply or a request.  For
 * request evaluation, simply pass "NULL" for the reply_block.
 * Note that it is assumed that the reply has already been
 * matched to the key (and signatures checked) as it would
 * be done with the "get_key" function.
 *
 * @param cls closure
 * @param type block type
 * @param query original query (hash)
 * @param bf pointer to bloom filter associated with query; possibly updated (!)
 * @param bf_mutator mutation value for bf
 * @param xquery extrended query data (can be NULL, depending on type)
 * @param xquery_size number of bytes in xquery
 * @param reply_block response to validate
 * @param reply_block_size number of bytes in reply block
 * @return characterization of result
 */
static enum GNUNET_BLOCK_EvaluationResult
block_plugin_regex_evaluate (void *cls, enum GNUNET_BLOCK_Type type,
                             const struct GNUNET_HashCode * query,
                             struct GNUNET_CONTAINER_BloomFilter **bf,
                             int32_t bf_mutator, const void *xquery,
                             size_t xquery_size, const void *reply_block,
                             size_t reply_block_size)
{
  enum GNUNET_BLOCK_EvaluationResult result;

  switch (type)
  {
    case GNUNET_BLOCK_TYPE_REGEX:
      result = evaluate_block_regex (cls, type, query, bf, bf_mutator,
                                     xquery, xquery_size,
                                     reply_block, reply_block_size);
      break;
    case GNUNET_BLOCK_TYPE_REGEX_ACCEPT:
      result = evaluate_block_regex_accept (cls, type, query, bf, bf_mutator,
                                            xquery, xquery_size,
                                            reply_block, reply_block_size);
      break;

    default:
      result = GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
  }
  return result;
}


/**
 * Function called to obtain the key for a block.
 *
 * @param cls closure
 * @param type block type
 * @param block block to get the key for
 * @param block_size number of bytes in block
 * @param key set to the key (query) for the given block
 * @return GNUNET_OK on success, GNUNET_SYSERR if type not supported
 *         (or if extracting a key from a block of this type does not work)
 */
static int
block_plugin_regex_get_key (void *cls, enum GNUNET_BLOCK_Type type,
                            const void *block, size_t block_size,
                            struct GNUNET_HashCode * key)
{
  switch (type)
  {
    case GNUNET_BLOCK_TYPE_REGEX:
      if (GNUNET_OK !=
	  REGEX_BLOCK_get_key (block, block_size,
			       key))
      {
	GNUNET_break_op (0);
	return GNUNET_NO;
      }
      return GNUNET_OK;
    case GNUNET_BLOCK_TYPE_REGEX_ACCEPT:
      if (sizeof (struct RegexAcceptBlock) != block_size)
      {
	GNUNET_break_op (0);
	return GNUNET_NO;
      }
      *key = ((struct RegexAcceptBlock *) block)->key;
      return GNUNET_OK;
    default:
      GNUNET_break (0);
      return GNUNET_SYSERR;
  }
}


/**
 * Entry point for the plugin.
 */
void *
libgnunet_plugin_block_regex_init (void *cls)
{
  static enum GNUNET_BLOCK_Type types[] =
  {
    GNUNET_BLOCK_TYPE_REGEX,
    GNUNET_BLOCK_TYPE_REGEX_ACCEPT,
    GNUNET_BLOCK_TYPE_ANY       /* end of list */
  };
  struct GNUNET_BLOCK_PluginFunctions *api;

  api = GNUNET_new (struct GNUNET_BLOCK_PluginFunctions);
  api->evaluate = &block_plugin_regex_evaluate;
  api->get_key = &block_plugin_regex_get_key;
  api->types = types;
  return api;
}


/**
 * Exit point from the plugin.
 */
void *
libgnunet_plugin_block_regex_done (void *cls)
{
  struct GNUNET_TRANSPORT_PluginFunctions *api = cls;

  GNUNET_free (api);
  return NULL;
}

/* end of plugin_block_regex.c */