GNUnet  0.17.6
fs_publish_ublock.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2009, 2010, 2012, 2013 GNUnet e.V.
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 
28 #include "platform.h"
29 #include "gnunet_constants.h"
30 #include "gnunet_signatures.h"
31 #include "fs_publish_ublock.h"
32 #include "fs_api.h"
33 #include "fs_tree.h"
34 
35 
45 static void
48  *iv,
49  const char *label,
50  const struct GNUNET_CRYPTO_EcdsaPublicKey *pub)
51 {
52  struct GNUNET_HashCode key;
53 
54  /* derive key from 'label' and public key of the namespace */
56  GNUNET_CRYPTO_kdf (&key, sizeof(key),
57  "UBLOCK-ENC", strlen ("UBLOCK-ENC"),
58  label, strlen (label),
59  pub, sizeof(*pub),
60  NULL, 0));
62 }
63 
64 
65 void
66 GNUNET_FS_ublock_decrypt_ (const void *input,
67  size_t input_len,
68  const struct GNUNET_CRYPTO_EcdsaPublicKey *ns,
69  const char *label,
70  void *output)
71 {
74 
75  derive_ublock_encryption_key (&skey, &iv,
76  label, ns);
77  GNUNET_CRYPTO_symmetric_decrypt (input, input_len,
78  &skey, &iv,
79  output);
80 }
81 
82 
87 {
92 
96  void *cont_cls;
97 
102 
107 };
108 
109 
122 static void
123 ublock_put_cont (void *cls,
124  int32_t success,
126  const char *msg)
127 {
128  struct GNUNET_FS_PublishUblockContext *uc = cls;
129 
130  uc->qre = NULL;
131  uc->cont (uc->cont_cls, msg);
132  GNUNET_free (uc);
133 }
134 
135 
141 static void
142 run_cont (void *cls)
143 {
144  struct GNUNET_FS_PublishUblockContext *uc = cls;
145 
146  uc->task = NULL;
147  uc->cont (uc->cont_cls, NULL);
148  GNUNET_free (uc);
149 }
150 
151 
155  const char *label,
156  const char *ulabel,
157  const struct GNUNET_CRYPTO_EcdsaPrivateKey *ns,
158  const struct GNUNET_CONTAINER_MetaData *meta,
159  const struct GNUNET_FS_Uri *uri,
160  const struct GNUNET_FS_BlockOptions *bo,
163 {
165  struct GNUNET_HashCode query;
168  struct GNUNET_CRYPTO_EcdsaPrivateKey *nsd;
170  char *uris;
171  size_t size;
172  char *kbe;
173  char *sptr;
174  ssize_t mdsize;
175  size_t slen;
176  size_t ulen;
177  struct UBlock *ub_plain;
178  struct UBlock *ub_enc;
179 
180  /* compute ublock to publish */
181  if (NULL == meta)
182  mdsize = 0;
183  else
185  GNUNET_assert (mdsize >= 0);
186  uris = GNUNET_FS_uri_to_string (uri);
187  slen = strlen (uris) + 1;
188  if (NULL == ulabel)
189  ulen = 1;
190  else
191  ulen = strlen (ulabel) + 1;
192  size = mdsize + sizeof(struct UBlock) + slen + ulen;
193  if (size > MAX_UBLOCK_SIZE)
194  {
196  mdsize = size - sizeof(struct UBlock) - (slen + ulen);
197  }
198  ub_plain = GNUNET_malloc (size);
199  kbe = (char *) &ub_plain[1];
200  if (NULL != ulabel)
201  GNUNET_memcpy (kbe, ulabel, ulen);
202  kbe += ulen;
203  GNUNET_memcpy (kbe, uris, slen);
204  kbe += slen;
205  GNUNET_free (uris);
206  sptr = kbe;
207  if (NULL != meta)
208  mdsize =
211  if (-1 == mdsize)
212  {
213  GNUNET_break (0);
214  GNUNET_free (ub_plain);
215  cont (cont_cls, _ ("Internal error."));
216  return NULL;
217  }
218  size = sizeof(struct UBlock) + slen + mdsize + ulen;
219 
221  "Publishing under identifier `%s'\n",
222  label);
223  /* get public key of the namespace */
225  &pub);
226  derive_ublock_encryption_key (&skey, &iv,
227  label, &pub);
228 
229  /* encrypt ublock */
230  ub_enc = GNUNET_malloc (size);
231  GNUNET_CRYPTO_symmetric_encrypt (&ub_plain[1],
232  ulen + slen + mdsize,
233  &skey, &iv,
234  &ub_enc[1]);
235  GNUNET_free (ub_plain);
236  ub_enc->purpose.size = htonl (ulen + slen + mdsize
237  + sizeof(struct UBlock)
238  - sizeof(struct GNUNET_CRYPTO_EcdsaSignature));
240 
241  /* derive signing-key from 'label' and public key of the namespace */
242  nsd = GNUNET_CRYPTO_ecdsa_private_key_derive (ns, label, "fs-ublock");
244  &ub_enc->verification_key);
247  &ub_enc->purpose,
248  &ub_enc->signature));
250  sizeof(ub_enc->verification_key),
251  &query);
252  GNUNET_free (nsd);
253 
255  uc->cont = cont;
256  uc->cont_cls = cont_cls;
257  if (NULL != dsh)
258  {
259  uc->qre =
261  0,
262  &query,
263  ulen + slen + mdsize + sizeof(struct UBlock),
264  ub_enc,
270  -2, 1,
271  &ublock_put_cont, uc);
272  }
273  else
274  {
276  uc);
277  }
278  GNUNET_free (ub_enc);
279  return uc;
280 }
281 
282 
288 void
290 {
291  if (NULL != uc->qre)
293  if (NULL != uc->task)
294  GNUNET_SCHEDULER_cancel (uc->task);
295  GNUNET_free (uc);
296 }
297 
298 
299 /* end of fs_publish_ublock.c */
struct GNUNET_GETOPT_CommandLineOption options[]
Definition: 002.c:5
struct GNUNET_MessageHeader * msg
Definition: 005.c:2
@ GNUNET_BLOCK_TYPE_FS_UBLOCK
Type of a block representing any type of search result (universal).
#define GNUNET_SIGNATURE_PURPOSE_FS_UBLOCK
UBlock Signature, done using DSS, not ECC (GNUnet-FS)
shared definitions for the FS library
static void run_cont(void *cls)
Run the continuation.
static void derive_ublock_encryption_key(struct GNUNET_CRYPTO_SymmetricSessionKey *skey, struct GNUNET_CRYPTO_SymmetricInitializationVector *iv, const char *label, const struct GNUNET_CRYPTO_EcdsaPublicKey *pub)
Derive the key for symmetric encryption/decryption from the public key and the label.
void GNUNET_FS_ublock_decrypt_(const void *input, size_t input_len, const struct GNUNET_CRYPTO_EcdsaPublicKey *ns, const char *label, void *output)
Decrypt the given UBlock, storing the result in output.
void GNUNET_FS_publish_ublock_cancel_(struct GNUNET_FS_PublishUblockContext *uc)
Abort UBlock publishing operation.
static void ublock_put_cont(void *cls, int32_t success, struct GNUNET_TIME_Absolute min_expiration, const char *msg)
Continuation of GNUNET_FS_publish_ublock_().
struct GNUNET_FS_PublishUblockContext * GNUNET_FS_publish_ublock_(struct GNUNET_FS_Handle *h, struct GNUNET_DATASTORE_Handle *dsh, const char *label, const char *ulabel, const struct GNUNET_CRYPTO_EcdsaPrivateKey *ns, const struct GNUNET_CONTAINER_MetaData *meta, const struct GNUNET_FS_Uri *uri, const struct GNUNET_FS_BlockOptions *bo, enum GNUNET_FS_PublishOptions options, GNUNET_FS_UBlockContinuation cont, void *cont_cls)
Publish a UBlock.
publish a UBLOCK in GNUnet
void(* GNUNET_FS_UBlockContinuation)(void *cls, const char *emsg)
Signature of a function called as the continuation of a UBlock publication.
Merkle-tree-ish-CHK file encoding for GNUnet.
static struct GNUNET_NAMESTORE_Handle * ns
Handle to the namestore.
Definition: gnunet-abd.c:41
static struct GNUNET_ARM_Handle * h
Connection with ARM.
Definition: gnunet-arm.c:99
struct GNUNET_HashCode key
The key used in the DHT.
static struct GNUNET_FS_Uri * uri
Value of URI provided on command-line (when not publishing a file but just creating UBlocks to refer ...
static struct GNUNET_FS_BlockOptions bo
Options we set for published blocks.
static struct GNUNET_CONTAINER_MetaData * meta
Meta-data provided via command-line option.
static struct GNUNET_CRYPTO_EddsaPublicKey pub
Definition: gnunet-scrypt.c:46
static struct GNUNET_TIME_Absolute min_expiration
Minimum time that content should have to not be discarded instantly (time stamp of any content that w...
static struct GNUNET_DATASTORE_Handle * dsh
Datastore handle.
static struct GNUNET_FS_UnindexContext * uc
#define MAX_UBLOCK_SIZE
Maximum legal size for a ublock.
Definition: block_fs.h:41
enum GNUNET_GenericReturnValue GNUNET_CRYPTO_ecdsa_sign_(const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv, const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose, struct GNUNET_CRYPTO_EcdsaSignature *sig)
ECDSA Sign a given block.
Definition: crypto_ecc.c:549
ssize_t GNUNET_CRYPTO_symmetric_encrypt(const void *block, size_t size, const struct GNUNET_CRYPTO_SymmetricSessionKey *sessionkey, const struct GNUNET_CRYPTO_SymmetricInitializationVector *iv, void *result)
Encrypt a block using a symmetric sessionkey.
void GNUNET_CRYPTO_ecdsa_key_get_public(const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv, struct GNUNET_CRYPTO_EcdsaPublicKey *pub)
Extract the public key for the given private key.
Definition: crypto_ecc.c:186
struct GNUNET_CRYPTO_EcdsaPrivateKey * GNUNET_CRYPTO_ecdsa_private_key_derive(const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv, const char *label, const char *context)
Derive a private key from a given private key and a label.
ssize_t GNUNET_CRYPTO_symmetric_decrypt(const void *block, size_t size, const struct GNUNET_CRYPTO_SymmetricSessionKey *sessionkey, const struct GNUNET_CRYPTO_SymmetricInitializationVector *iv, void *result)
Decrypt a given block using a symmetric sessionkey.
void GNUNET_DATASTORE_cancel(struct GNUNET_DATASTORE_QueueEntry *qe)
Cancel a datastore operation.
struct GNUNET_DATASTORE_QueueEntry * GNUNET_DATASTORE_put(struct GNUNET_DATASTORE_Handle *h, uint32_t rid, const struct GNUNET_HashCode *key, size_t size, const void *data, enum GNUNET_BLOCK_Type type, uint32_t priority, uint32_t anonymity, uint32_t replication, struct GNUNET_TIME_Absolute expiration, unsigned int queue_priority, unsigned int max_queue_size, GNUNET_DATASTORE_ContinuationWithStatus cont, void *cont_cls)
Store an item in the datastore.
GNUNET_FS_PublishOptions
Options for publishing.
char * GNUNET_FS_uri_to_string(const struct GNUNET_FS_Uri *uri)
Convert a URI to a UTF-8 String.
Definition: fs_uri.c:2033
void GNUNET_CRYPTO_hash(const void *block, size_t size, struct GNUNET_HashCode *ret)
Compute hash of a given block.
Definition: crypto_hash.c:41
enum GNUNET_GenericReturnValue GNUNET_CRYPTO_kdf(void *result, size_t out_len, const void *xts, size_t xts_len, const void *skm, size_t skm_len,...)
Derive key.
Definition: crypto_kdf.c:69
void GNUNET_CRYPTO_hash_to_aes_key(const struct GNUNET_HashCode *hc, struct GNUNET_CRYPTO_SymmetricSessionKey *skey, struct GNUNET_CRYPTO_SymmetricInitializationVector *iv)
Convert a hashcode into a key.
Definition: crypto_hash.c:151
#define GNUNET_log(kind,...)
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
@ GNUNET_OK
Definition: gnunet_common.h:99
@ GNUNET_YES
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur.
@ GNUNET_ERROR_TYPE_DEBUG
#define GNUNET_new(type)
Allocate a struct or union of the given type.
#define GNUNET_malloc(size)
Wrapper around malloc.
#define GNUNET_free(ptr)
Wrapper around free.
ssize_t GNUNET_CONTAINER_meta_data_serialize(const struct GNUNET_CONTAINER_MetaData *md, char **target, size_t max, enum GNUNET_CONTAINER_MetaDataSerializationOptions opt)
Serialize meta-data to target.
ssize_t GNUNET_CONTAINER_meta_data_get_serialized_size(const struct GNUNET_CONTAINER_MetaData *md)
Get the size of the full meta-data in serialized form.
@ GNUNET_CONTAINER_META_DATA_SERIALIZE_PART
If not enough space is available, it is acceptable to only serialize some of the metadata.
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_now(GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run as soon as possible.
Definition: scheduler.c:1281
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:957
static unsigned int size
Size of the "table".
Definition: peer.c:67
#define _(String)
GNU gettext support macro.
Definition: platform.h:177
Meta data to associate with a file, directory or namespace.
uint32_t size
How many bytes does this signature sign? (including this purpose header); in network byte order (!...
uint32_t purpose
What does this signature vouch for? This must contain a GNUNET_SIGNATURE_PURPOSE_XXX constant (from g...
Private ECC key encoded for transmission.
Public ECC key (always for Curve25519) encoded in a format suitable for network transmission and ECDS...
an ECC signature using ECDSA
Handle to the datastore service.
Entry in our priority queue.
Settings for publishing a block (which may of course also apply to an entire directory or file).
uint32_t anonymity_level
At which anonymity level should the block be shared? (0: no anonymity, 1: normal GAP,...
uint32_t content_priority
How important is it for us to store the block? If we run out of space, the highest-priority,...
uint32_t replication_level
How often should we try to migrate the block to other peers? Only used if "CONTENT_PUSHING" is set to...
struct GNUNET_TIME_Absolute expiration_time
At what time should the block expire? Data blocks (DBLOCKS and IBLOCKS) may still be used even if the...
Master context for most FS operations.
Definition: fs_api.h:1069
Context for 'ublock_put_cont'.
struct GNUNET_DATASTORE_QueueEntry * qre
Handle for active datastore operation.
void * cont_cls
Closure of 'cont'.
struct GNUNET_SCHEDULER_Task * task
Task to run continuation asynchronously.
GNUNET_FS_UBlockContinuation cont
Function to call when done.
A Universal Resource Identifier (URI), opaque.
Definition: fs_api.h:166
A 512-bit hashcode.
Entry in list of pending tasks.
Definition: scheduler.c:135
Time for absolute times used by GNUnet, in microseconds.
universal block for keyword and namespace search results
Definition: block_fs.h:50
struct GNUNET_CRYPTO_EcdsaPublicKey verification_key
Public key used to sign this block.
Definition: block_fs.h:64
struct GNUNET_CRYPTO_EccSignaturePurpose purpose
What is being signed and why?
Definition: block_fs.h:59
struct GNUNET_CRYPTO_EcdsaSignature signature
Signature using pseudonym and search keyword / identifier.
Definition: block_fs.h:54