GNUnet  0.10.x
crypto_abe.c
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1 /*
2  This file is part of GNUnet. Copyright (C) 2001-2014 Christian Grothoff
3  (and other contributing authors)
4 
5  GNUnet is free software: you can redistribute it and/or modify it
6  under the terms of the GNU Affero General Public License as published
7  by the Free Software Foundation, either version 3 of the License,
8  or (at your option) any later version.
9 
10  GNUnet is distributed in the hope that it will be useful, but
11  WITHOUT ANY WARRANTY; without even the implied warranty of
12  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  Affero General Public License for more details.
14 
15  You should have received a copy of the GNU Affero General Public License
16  along with this program. If not, see <http://www.gnu.org/licenses/>.
17 
18  SPDX-License-Identifier: AGPL3.0-or-later
19 
20  */
21 
29 #include "platform.h"
30 #include <pbc/pbc.h>
31 #include <gabe.h>
32 
33 #include "gnunet_crypto_lib.h"
34 
36  gabe_pub_t* pub;
37  gabe_msk_t* msk;
38 };
39 
41  gabe_pub_t* pub;
42  gabe_prv_t* prv;
43 };
44 
45 static int
46 init_aes(element_t k, int enc,
47  gcry_cipher_hd_t* handle,
49  unsigned char* iv)
50 {
51  int rc;
52  int key_len;
53  unsigned char* key_buf;
54 
55  key_len = element_length_in_bytes(k) < 33 ? 3 : element_length_in_bytes(k);
56  key_buf = (unsigned char*)malloc(key_len);
57  element_to_bytes(key_buf, k);
58 
60  key_buf,
62  GNUNET_assert(0 ==
63  gcry_cipher_open(handle, GCRY_CIPHER_AES256,
64  GCRY_CIPHER_MODE_CFB, 0));
65  rc = gcry_cipher_setkey(*handle,
66  key->aes_key,
67  sizeof(key->aes_key));
68  GNUNET_assert((0 == rc) || ((char)rc == GPG_ERR_WEAK_KEY));
69  memset(iv, 0, 16); //TODO make reasonable
70  rc = gcry_cipher_setiv(*handle,
71  iv,
72  16);
73  GNUNET_assert((0 == rc) || ((char)rc == GPG_ERR_WEAK_KEY));
74 
75  free(key_buf);
76  return rc;
77 }
78 
79 static int
81  int size,
82  element_t k,
83  char **ct)
84 {
85  gcry_cipher_hd_t handle;
87  unsigned char iv[16];
88  char* buf;
89  int padding;
90  int buf_size;
91  uint8_t len[4];
92 
93  init_aes(k, 1, &handle, &skey, iv);
94 
95  /* TODO make less crufty */
96 
97  /* stuff in real length (big endian) before padding */
98  len[0] = (size & 0xff000000) >> 24;
99  len[1] = (size & 0xff0000) >> 16;
100  len[2] = (size & 0xff00) >> 8;
101  len[3] = (size & 0xff) >> 0;
102  padding = 16 - ((4 + size) % 16);
103  buf_size = 4 + size + padding;
104  buf = GNUNET_malloc(buf_size);
105  GNUNET_memcpy(buf, len, 4);
106  GNUNET_memcpy(buf + 4, pt, size);
107  *ct = GNUNET_malloc(buf_size);
108 
109  GNUNET_assert(0 == gcry_cipher_encrypt(handle, *ct, buf_size, buf, buf_size));
110  gcry_cipher_close(handle);
111  //AES_cbc_encrypt(pt->data, ct->data, pt->len, &key, iv, AES_ENCRYPT);
112  GNUNET_free(buf);
113  return buf_size;
114 }
115 
116 static int
118  int size,
119  element_t k,
120  char **pt)
121 {
123  gcry_cipher_hd_t handle;
124  unsigned char iv[16];
125  char* tmp;
126  uint32_t len;
127 
128  init_aes(k, 1, &handle, &skey, iv);
129 
130  tmp = GNUNET_malloc(size);
131 
132  //AES_cbc_encrypt(ct->data, pt->data, ct->len, &key, iv, AES_DECRYPT);
133  GNUNET_assert(0 == gcry_cipher_decrypt(handle, tmp, size, ct, size));
134  gcry_cipher_close(handle);
135  /* TODO make less crufty */
136 
137  /* get real length */
138  len = 0;
139  len = len
140  | ((tmp[0]) << 24) | ((tmp[1]) << 16)
141  | ((tmp[2]) << 8) | ((tmp[3]) << 0);
142  /* truncate any garbage from the padding */
143  *pt = GNUNET_malloc(len);
144  GNUNET_memcpy(*pt, tmp + 4, len);
145  GNUNET_free(tmp);
146  return len;
147 }
148 
151 {
153 
155  gabe_setup(&key->pub, &key->msk);
156  GNUNET_assert(NULL != key->pub);
157  GNUNET_assert(NULL != key->msk);
158  return key;
159 }
160 
161 void
163 {
164  gabe_msk_free(key->msk);
165  gabe_pub_free(key->pub);
166  //GNUNET_free (key->msk);
167  //gabe_msk_free (key->msk); //For some reason free of pub implicit?
168  GNUNET_free(key);
169 }
170 
171 struct GNUNET_CRYPTO_AbeKey*
173  char **attrs)
174 {
175  struct GNUNET_CRYPTO_AbeKey *prv_key;
176  int size;
177  char *tmp;
178 
179  prv_key = GNUNET_new(struct GNUNET_CRYPTO_AbeKey);
180  prv_key->prv = gabe_keygen(key->pub, key->msk, attrs);
181  size = gabe_pub_serialize(key->pub, &tmp);
182  prv_key->pub = gabe_pub_unserialize(tmp, size);
183  GNUNET_free(tmp);
184  GNUNET_assert(NULL != prv_key->prv);
185  return prv_key;
186 }
187 
188 void
190  int delete_pub)
191 {
192  //Memory management in gabe is buggy
193  gabe_prv_free(key->prv);
194  if (GNUNET_YES == delete_pub)
195  gabe_pub_free(key->pub);
196  GNUNET_free(key);
197 }
198 
199 ssize_t
201  uint32_t file_len,
202  char* cph_buf,
203  int cph_buf_len,
204  char* aes_buf,
205  int aes_buf_len)
206 {
207  char *ptr;
208  uint32_t *len;
209 
210  *result = GNUNET_malloc(12 + cph_buf_len + aes_buf_len);
211  ptr = *result;
212  len = (uint32_t*)ptr;
213  *len = htonl(file_len);
214  ptr += 4;
215  len = (uint32_t*)ptr;
216  *len = htonl(aes_buf_len);
217  ptr += 4;
218  GNUNET_memcpy(ptr, aes_buf, aes_buf_len);
219  ptr += aes_buf_len;
220  len = (uint32_t*)ptr;
221  *len = htonl(cph_buf_len);
222  ptr += 4;
223  GNUNET_memcpy(ptr, cph_buf, cph_buf_len);
224  return 12 + cph_buf_len + aes_buf_len;
225 }
226 
227 ssize_t
228 read_cpabe(const void *data,
229  char** cph_buf,
230  int *cph_buf_len,
231  char** aes_buf,
232  int *aes_buf_len)
233 {
234  int buf_len;
235  char *ptr;
236  uint32_t *len;
237 
238  ptr = (char*)data;
239  len = (uint32_t*)ptr;
240  buf_len = ntohl(*len);
241  ptr += 4;
242  len = (uint32_t*)ptr;
243  *aes_buf_len = ntohl(*len);
244  ptr += 4;
245  *aes_buf = GNUNET_malloc(*aes_buf_len);
246  GNUNET_memcpy(*aes_buf, ptr, *aes_buf_len);
247  ptr += *aes_buf_len;
248  len = (uint32_t*)ptr;
249  *cph_buf_len = ntohl(*len);
250  ptr += 4;
251  *cph_buf = GNUNET_malloc(*cph_buf_len);
252  GNUNET_memcpy(*cph_buf, ptr, *cph_buf_len);
253 
254  return buf_len;
255 }
256 
257 ssize_t
258 GNUNET_CRYPTO_cpabe_encrypt(const void *block,
259  size_t size,
260  const char *policy,
261  const struct GNUNET_CRYPTO_AbeMasterKey *key,
262  void **result)
263 {
264  gabe_cph_t* cph;
265  char* plt;
266  char* cph_buf;
267  char* aes_buf;
268  element_t m;
269  int cph_buf_len;
270  int aes_buf_len;
271  ssize_t result_len;
272 
273  if (!(cph = gabe_enc(key->pub, m, (char*)policy)))
274  return GNUNET_SYSERR;
275  cph_buf_len = gabe_cph_serialize(cph,
276  &cph_buf);
277  gabe_cph_free(cph);
278  GNUNET_free(cph);
279  plt = GNUNET_memdup(block, size);
280  aes_buf_len = aes_128_cbc_encrypt(plt, size, m, &aes_buf);
281  GNUNET_free(plt);
282  element_clear(m);
283  result_len = write_cpabe(result, size, cph_buf, cph_buf_len, aes_buf, aes_buf_len);
284  GNUNET_free(cph_buf);
285  GNUNET_free(aes_buf);
286  return result_len;
287 }
288 
289 ssize_t
290 GNUNET_CRYPTO_cpabe_decrypt(const void *block,
291  size_t size,
292  const struct GNUNET_CRYPTO_AbeKey *key,
293  void **result)
294 {
295  char* aes_buf;
296  char* cph_buf;
297  gabe_cph_t* cph;
298  element_t m;
299  int cph_buf_size;
300  int aes_buf_size;
301  int plt_len;
302 
303  read_cpabe(block, &cph_buf, &cph_buf_size, &aes_buf, &aes_buf_size);
304  cph = gabe_cph_unserialize(key->pub, cph_buf, cph_buf_size);
305  if (!gabe_dec(key->pub, key->prv, cph, m))
306  {
308  "%s\n", gabe_error());
309  GNUNET_free(aes_buf);
310  GNUNET_free(cph_buf);
311  gabe_cph_free(cph);
312  GNUNET_free(cph);
313  element_clear(m);
314  return GNUNET_SYSERR;
315  }
316  gabe_cph_free(cph);
317  GNUNET_free(cph);
318  plt_len = aes_128_cbc_decrypt(aes_buf, aes_buf_size, m, (char**)result);
319  GNUNET_free(cph_buf);
320  GNUNET_free(aes_buf);
321  element_clear(m);
322  //freeing is buggy in gabe
323  //gabe_prv_free (prv);
324  //gabe_pub_free (pub);
325  return plt_len;
326 }
327 
328 ssize_t
330  void **result)
331 {
332  ssize_t len;
333  char *pub;
334  char *prv;
335  int pub_len;
336  int prv_len;
337 
338  pub_len = gabe_pub_serialize(key->pub, &pub);
339  prv_len = gabe_prv_serialize(key->prv, &prv);
340 
341  len = pub_len + prv_len + 12;
342  write_cpabe(result, len, pub, pub_len, prv, prv_len);
343 
344  GNUNET_free(pub);
345  GNUNET_free(prv);
346 
347  return len;
348 }
349 
350 struct GNUNET_CRYPTO_AbeKey*
352  size_t len)
353 {
354  struct GNUNET_CRYPTO_AbeKey *key;
355  char *pub;
356  char *prv;
357  int prv_len;
358  int pub_len;
359 
360  key = GNUNET_new(struct GNUNET_CRYPTO_AbeKey);
361  read_cpabe(data,
362  &pub,
363  &pub_len,
364  &prv,
365  &prv_len);
366  key->pub = gabe_pub_unserialize(pub, pub_len);
367  key->prv = gabe_prv_unserialize(key->pub, prv, prv_len);
368 
369  GNUNET_free(pub);
370  GNUNET_free(prv);
371  return key;
372 }
373 
374 ssize_t
376  void **result)
377 {
378  ssize_t len;
379  char *pub;
380  char *msk;
381  int pub_len;
382  int msk_len;
383 
384  pub_len = gabe_pub_serialize(key->pub, &pub);
385  msk_len = gabe_msk_serialize(key->msk, &msk);
386 
387  len = pub_len + msk_len + 12;
388  write_cpabe(result, len, pub, pub_len, msk, msk_len);
389 
390  GNUNET_free(pub);
391  GNUNET_free(msk);
392 
393  return len;
394 }
395 
398  size_t len)
399 {
401  char *msk;
402  char *pub;
403  int msk_len;
404  int pub_len;
405 
407  read_cpabe(data,
408  &pub,
409  &pub_len,
410  &msk,
411  &msk_len);
412  key->pub = gabe_pub_unserialize(pub, pub_len);
413  key->msk = gabe_msk_unserialize(key->pub, msk, msk_len);
414 
415  GNUNET_free(pub);
416  GNUNET_free(msk);
417 
418  return key;
419 }
void GNUNET_CRYPTO_cpabe_delete_key(struct GNUNET_CRYPTO_AbeKey *key, int delete_pub)
Definition: crypto_abe.c:189
ssize_t GNUNET_CRYPTO_cpabe_serialize_key(const struct GNUNET_CRYPTO_AbeKey *key, void **result)
Definition: crypto_abe.c:329
static int init_aes(element_t k, int enc, gcry_cipher_hd_t *handle, struct GNUNET_CRYPTO_SymmetricSessionKey *key, unsigned char *iv)
Definition: crypto_abe.c:46
struct GNUNET_CRYPTO_AbeMasterKey * GNUNET_CRYPTO_cpabe_create_master_key(void)
Definition: crypto_abe.c:150
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
ssize_t read_cpabe(const void *data, char **cph_buf, int *cph_buf_len, char **aes_buf, int *aes_buf_len)
Definition: crypto_abe.c:228
struct GNUNET_CRYPTO_AbeMasterKey * GNUNET_CRYPTO_cpabe_deserialize_master_key(const void *data, size_t len)
Definition: crypto_abe.c:397
static int aes_128_cbc_encrypt(char *pt, int size, element_t k, char **ct)
Definition: crypto_abe.c:80
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
#define GNUNET_memdup(buf, size)
Allocate and initialize a block of memory.
struct GNUNET_CRYPTO_AbeKey * GNUNET_CRYPTO_cpabe_create_key(struct GNUNET_CRYPTO_AbeMasterKey *key, char **attrs)
Definition: crypto_abe.c:172
#define GNUNET_new(type)
Allocate a struct or union of the given type.
unsigned char aes_key[(256/8)]
Actual key for AES.
static struct GNUNET_ARM_MonitorHandle * m
Monitor connection with ARM.
Definition: gnunet-arm.c:99
cryptographic primitives for GNUnet
static int aes_128_cbc_decrypt(char *ct, int size, element_t k, char **pt)
Definition: crypto_abe.c:117
gabe_pub_t * pub
Definition: crypto_abe.c:41
ssize_t write_cpabe(void **result, uint32_t file_len, char *cph_buf, int cph_buf_len, char *aes_buf, int aes_buf_len)
Definition: crypto_abe.c:200
static char buf[2048]
ssize_t GNUNET_CRYPTO_cpabe_encrypt(const void *block, size_t size, const char *policy, const struct GNUNET_CRYPTO_AbeMasterKey *key, void **result)
Definition: crypto_abe.c:258
static struct GNUNET_DNS_Handle * handle
Handle to transport service.
static int result
Global testing status.
void GNUNET_CRYPTO_cpabe_delete_master_key(struct GNUNET_CRYPTO_AbeMasterKey *key)
Definition: crypto_abe.c:162
struct GNUNET_CRYPTO_AbeKey * GNUNET_CRYPTO_cpabe_deserialize_key(const void *data, size_t len)
Definition: crypto_abe.c:351
#define GNUNET_CRYPTO_AES_KEY_LENGTH
length of the sessionkey in bytes (256 BIT sessionkey)
struct GNUNET_HashCode key
The key used in the DHT.
#define GNUNET_SYSERR
Definition: gnunet_common.h:76
static unsigned int size
Size of the "table".
Definition: peer.c:66
ssize_t GNUNET_CRYPTO_cpabe_decrypt(const void *block, size_t size, const struct GNUNET_CRYPTO_AbeKey *key, void **result)
Definition: crypto_abe.c:290
static OpusEncoder * enc
OPUS encoder.
#define GNUNET_log(kind,...)
ssize_t GNUNET_CRYPTO_cpabe_serialize_master_key(const struct GNUNET_CRYPTO_AbeMasterKey *key, void **result)
Definition: crypto_abe.c:375
gabe_prv_t * prv
Definition: crypto_abe.c:42
#define GNUNET_YES
Definition: gnunet_common.h:77
uint32_t data
The data value.
#define GNUNET_malloc(size)
Wrapper around malloc.
#define GNUNET_free(ptr)
Wrapper around free.
uint16_t len
length of data (which is always a uint32_t, but presumably this can be used to specify that fewer byt...