summaryrefslogtreecommitdiff
path: root/src/credential/credential_serialization.c
blob: 99138441e48d51e83bf3aaf1021217fa79e35157 (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
/*
     This file is part of GNUnet.
     Copyright (C) 2009-2013, 2016 GNUnet e.V.

     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., 51 Franklin Street, Fifth Floor,
     Boston, MA 02110-1301, USA.
*/


/**
 * @file credential/credential_serialization.c
 * @brief API to serialize and deserialize delegation chains 
 * and credentials
 * @author Martin Schanzenbach
 */
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_constants.h"
#include "gnunet_credential_service.h"

GNUNET_NETWORK_STRUCT_BEGIN

struct DelegationRecordData
{
  /**
   * Subject key
   */
  struct GNUNET_CRYPTO_EcdsaPublicKey subject_key;
  
  /**
   * Subject attributes
   */
  uint32_t subject_attribute_len GNUNET_PACKED;
};


struct ChainEntry
{
  /**
   * Issuer key
   */
  struct GNUNET_CRYPTO_EcdsaPublicKey issuer_key;
  
  /**
   * Subject key
   */
  struct GNUNET_CRYPTO_EcdsaPublicKey subject_key;
  
  /**
   * Issuer attributes
   */
  uint32_t issuer_attribute_len GNUNET_PACKED;
  
  /**
   * Subject attributes
   */
  uint32_t subject_attribute_len GNUNET_PACKED;
};

GNUNET_NETWORK_STRUCT_END


/**
 * Calculate how many bytes we will need to serialize
 * the given delegation chain and credential
 *
 * @param d_count number of delegation chain entries
 * @param dd array of #GNUNET_CREDENTIAL_Delegation
 * @param cd a #GNUNET_CREDENTIAL_Credential
 * @return the required size to serialize
 */
size_t
GNUNET_CREDENTIAL_delegation_set_get_size (unsigned int ds_count,
                                           const struct GNUNET_CREDENTIAL_DelegationSetRecord *dsr)
{
  unsigned int i;
  size_t ret;

  ret = sizeof (struct DelegationRecordData) * (ds_count);

  for (i=0; i<ds_count;i++)
  {
    GNUNET_assert ((ret + dsr[i].subject_attribute_len) >= ret);
    ret += dsr[i].subject_attribute_len;
  }
  return ret;
}

/**
 * Serizalize the given delegation chain entries and credential
 *
 * @param d_count number of delegation chain entries
 * @param dd array of #GNUNET_CREDENTIAL_Delegation
 * @param cd a #GNUNET_CREDENTIAL_Credential
 * @param dest_size size of the destination
 * @param dest where to store the result
 * @return the size of the data, -1 on failure
 */
ssize_t
GNUNET_CREDENTIAL_delegation_set_serialize (unsigned int d_count,
                                            const struct GNUNET_CREDENTIAL_DelegationSetRecord *dsr,
                                            size_t dest_size,
                                            char *dest)
{
  struct DelegationRecordData rec;
  unsigned int i;
  size_t off;

  off = 0;
  for (i=0;i<d_count;i++)
  {
    rec.subject_attribute_len = htonl ((uint32_t) dsr[i].subject_attribute_len);
    rec.subject_key = dsr[i].subject_key;
    if (off + sizeof (rec) > dest_size)
      return -1;
    GNUNET_memcpy (&dest[off],
                   &rec,
                   sizeof (rec));
    off += sizeof (rec);
    if (0 == dsr[i].subject_attribute_len)
      continue;
    if (off + dsr[i].subject_attribute_len > dest_size)
      return -1;
    GNUNET_memcpy (&dest[off],
                   dsr[i].subject_attribute,
                   dsr[i].subject_attribute_len);
    off += dsr[i].subject_attribute_len;
  }
  return off;
}


/**
 * Deserialize the given destination
 *
 * @param len size of the serialized delegation chain and cred
 * @param src the serialized data
 * @param d_count the number of delegation chain entries
 * @param dd where to put the delegation chain entries
 * @param cd where to put the credential data
 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
 */
int
GNUNET_CREDENTIAL_delegation_set_deserialize (size_t len,
                                              const char *src,
                                              unsigned int d_count,
                                              struct GNUNET_CREDENTIAL_DelegationSetRecord *dsr)
{
  struct DelegationRecordData rec;
  unsigned int i;
  size_t off;

  off = 0;
  for (i=0;i<d_count;i++)
  {
    if (off + sizeof (rec) > len)
      return GNUNET_SYSERR;
    GNUNET_memcpy (&rec, &src[off], sizeof (rec));
    dsr[i].subject_key = rec.subject_key;
    off += sizeof (rec);
    dsr[i].subject_attribute_len = ntohl ((uint32_t) rec.subject_attribute_len);
    if (off + dsr[i].subject_attribute_len > len)
      return GNUNET_SYSERR;
    dsr[i].subject_attribute = &src[off];
    off += dsr[i].subject_attribute_len;
  }
  return GNUNET_OK;
}
/**
 * Calculate how many bytes we will need to serialize
 * the given delegation chain and credential
 *
 * @param d_count number of delegation chain entries
 * @param dd array of #GNUNET_CREDENTIAL_Delegation
 * @param cd a #GNUNET_CREDENTIAL_Credential
 * @return the required size to serialize
 */
size_t
GNUNET_CREDENTIAL_delegation_chain_get_size (unsigned int d_count,
                                             const struct GNUNET_CREDENTIAL_Delegation *dd,
                                             const struct GNUNET_CREDENTIAL_Credential *cd)
{
  unsigned int i;
  size_t ret;

  ret = sizeof (struct ChainEntry) * (d_count + 1);

  for (i=0; i<d_count;i++)
  {
    GNUNET_assert ((ret +
                    dd[i].issuer_attribute_len +
                    dd[i].subject_attribute_len) >= ret);
    ret += dd[i].issuer_attribute_len + dd[i].subject_attribute_len;
  }
  GNUNET_assert ((ret + cd->issuer_attribute_len) >= ret);
  ret += cd->issuer_attribute_len;
  return ret;
}

/**
 * Serizalize the given delegation chain entries and credential
 *
 * @param d_count number of delegation chain entries
 * @param dd array of #GNUNET_CREDENTIAL_Delegation
 * @param cd a #GNUNET_CREDENTIAL_Credential
 * @param dest_size size of the destination
 * @param dest where to store the result
 * @return the size of the data, -1 on failure
 */
ssize_t
GNUNET_CREDENTIAL_delegation_chain_serialize (unsigned int d_count,
                                              const struct GNUNET_CREDENTIAL_Delegation *dd,
                                              const struct GNUNET_CREDENTIAL_Credential *cd,
                                              size_t dest_size,
                                              char *dest)
{
  struct ChainEntry rec;
  unsigned int i;
  size_t off;

  off = 0;
  for (i=0;i<d_count;i++)
  {
    rec.issuer_attribute_len = htonl ((uint32_t) dd[i].issuer_attribute_len);
    rec.subject_attribute_len = htonl ((uint32_t) dd[i].subject_attribute_len);
    rec.issuer_key = dd[i].issuer_key;
    rec.subject_key = dd[i].subject_key;
    if (off + sizeof (rec) > dest_size)
      return -1;
    GNUNET_memcpy (&dest[off],
                   &rec,
                   sizeof (rec));
    off += sizeof (rec);
    if (off + dd[i].issuer_attribute_len > dest_size)
      return -1;
    GNUNET_memcpy (&dest[off],
                   dd[i].issuer_attribute,
                   dd[i].issuer_attribute_len);
    off += dd[i].issuer_attribute_len;
    if (0 == dd[i].subject_attribute_len)
      continue;
    if (off + dd[i].subject_attribute_len > dest_size)
      return -1;
    GNUNET_memcpy (&dest[off],
                   dd[i].subject_attribute,
                   dd[i].subject_attribute_len);
    off += dd[i].subject_attribute_len;
  }
  rec.issuer_attribute_len = htonl ((uint32_t) cd->issuer_attribute_len);
  rec.subject_attribute_len = htonl (0);
  rec.issuer_key = cd->issuer_key;
  if (off + sizeof (rec) > dest_size)
    return -1;
  GNUNET_memcpy (&dest[off],
                 &rec,
                 sizeof (rec));
  off += sizeof (rec);
  if (off + cd->issuer_attribute_len > dest_size)
    return -1;
  GNUNET_memcpy (&dest[off],
                 cd->issuer_attribute,
                 cd->issuer_attribute_len);
  off += cd->issuer_attribute_len;

  return off;
}


/**
 * Deserialize the given destination
 *
 * @param len size of the serialized delegation chain and cred
 * @param src the serialized data
 * @param d_count the number of delegation chain entries
 * @param dd where to put the delegation chain entries
 * @param cd where to put the credential data
 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
 */
int
GNUNET_CREDENTIAL_delegation_chain_deserialize (size_t len,
                                                const char *src,
                                                unsigned int d_count,
                                                struct GNUNET_CREDENTIAL_Delegation *dd,
                                                struct GNUNET_CREDENTIAL_Credential *cd)
{
  struct ChainEntry rec;
  unsigned int i;
  size_t off;

  off = 0;
  for (i=0;i<d_count;i++)
  {
    if (off + sizeof (rec) > len)
      return GNUNET_SYSERR;
    GNUNET_memcpy (&rec, &src[off], sizeof (rec));
    dd[i].issuer_attribute_len = ntohl ((uint32_t) rec.issuer_attribute_len);
    dd[i].issuer_key = rec.issuer_key;
    dd[i].subject_key = rec.subject_key;
    off += sizeof (rec);
    if (off + dd[i].issuer_attribute_len > len)
      return GNUNET_SYSERR;
    dd[i].issuer_attribute = &src[off];
    off += dd[i].issuer_attribute_len;
    dd[i].subject_attribute_len = ntohl ((uint32_t) rec.subject_attribute_len);
    if (off + dd[i].subject_attribute_len > len)
      return GNUNET_SYSERR;
    dd[i].subject_attribute = &src[off];
    off += dd[i].subject_attribute_len;
  }
  if (off + sizeof (rec) > len)
    return GNUNET_SYSERR;
  GNUNET_memcpy (&rec, &src[off], sizeof (rec));
  cd->issuer_attribute_len = ntohl ((uint32_t) rec.issuer_attribute_len);
  cd->issuer_key = rec.issuer_key;
  cd->subject_key = rec.subject_key;
  off += sizeof (rec);
  if (off + cd->issuer_attribute_len > len)
    return GNUNET_SYSERR;
  cd->issuer_attribute = &src[off];
  off += cd->issuer_attribute_len;
  return GNUNET_OK;
}

/* end of credential_serialization.c */