GNUnet  0.10.x
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  const char *label,
49  const struct GNUNET_CRYPTO_EcdsaPublicKey *pub)
50 {
51  struct GNUNET_HashCode key;
52 
53  /* derive key from 'label' and public key of the namespace */
55  GNUNET_CRYPTO_kdf(&key, sizeof(key),
56  "UBLOCK-ENC", strlen("UBLOCK-ENC"),
57  label, strlen(label),
58  pub, sizeof(*pub),
59  NULL, 0));
60  GNUNET_CRYPTO_hash_to_aes_key(&key, skey, iv);
61 }
62 
63 
73 void
74 GNUNET_FS_ublock_decrypt_(const void *input,
75  size_t input_len,
76  const struct GNUNET_CRYPTO_EcdsaPublicKey *ns,
77  const char *label,
78  void *output)
79 {
82 
84  label, ns);
85  GNUNET_CRYPTO_symmetric_decrypt(input, input_len,
86  &skey, &iv,
87  output);
88 }
89 
90 
99 
103  void *cont_cls;
104 
109 
114 };
115 
116 
129 static void
130 ublock_put_cont(void *cls,
131  int32_t success,
133  const char *msg)
134 {
135  struct GNUNET_FS_PublishUblockContext *uc = cls;
136 
137  uc->qre = NULL;
138  uc->cont(uc->cont_cls, msg);
139  GNUNET_free(uc);
140 }
141 
142 
148 static void
149 run_cont(void *cls)
150 {
151  struct GNUNET_FS_PublishUblockContext *uc = cls;
152 
153  uc->task = NULL;
154  uc->cont(uc->cont_cls, NULL);
155  GNUNET_free(uc);
156 }
157 
158 
178  const char *label,
179  const char *ulabel,
180  const struct GNUNET_CRYPTO_EcdsaPrivateKey *ns,
181  const struct GNUNET_CONTAINER_MetaData *meta,
182  const struct GNUNET_FS_Uri *uri,
183  const struct GNUNET_FS_BlockOptions *bo,
186 {
188  struct GNUNET_HashCode query;
191  struct GNUNET_CRYPTO_EcdsaPrivateKey *nsd;
192  struct GNUNET_CRYPTO_EcdsaPublicKey pub;
193  char *uris;
194  size_t size;
195  char *kbe;
196  char *sptr;
197  ssize_t mdsize;
198  size_t slen;
199  size_t ulen;
200  struct UBlock *ub_plain;
201  struct UBlock *ub_enc;
202 
203  /* compute ublock to publish */
204  if (NULL == meta)
205  mdsize = 0;
206  else
208  GNUNET_assert(mdsize >= 0);
209  uris = GNUNET_FS_uri_to_string(uri);
210  slen = strlen(uris) + 1;
211  if (NULL == ulabel)
212  ulen = 1;
213  else
214  ulen = strlen(ulabel) + 1;
215  size = mdsize + sizeof(struct UBlock) + slen + ulen;
216  if (size > MAX_UBLOCK_SIZE)
217  {
218  size = MAX_UBLOCK_SIZE;
219  mdsize = size - sizeof(struct UBlock) - (slen + ulen);
220  }
221  ub_plain = GNUNET_malloc(size);
222  kbe = (char *)&ub_plain[1];
223  if (NULL != ulabel)
224  GNUNET_memcpy(kbe, ulabel, ulen);
225  kbe += ulen;
226  GNUNET_memcpy(kbe, uris, slen);
227  kbe += slen;
228  GNUNET_free(uris);
229  sptr = kbe;
230  if (NULL != meta)
231  mdsize =
232  GNUNET_CONTAINER_meta_data_serialize(meta, &sptr, mdsize,
234  if (-1 == mdsize)
235  {
236  GNUNET_break(0);
237  GNUNET_free(ub_plain);
238  cont(cont_cls, _("Internal error."));
239  return NULL;
240  }
241  size = sizeof(struct UBlock) + slen + mdsize + ulen;
242 
244  "Publishing under identifier `%s'\n",
245  label);
246  /* get public key of the namespace */
248  &pub);
249  derive_ublock_encryption_key(&skey, &iv,
250  label, &pub);
251 
252  /* encrypt ublock */
253  ub_enc = GNUNET_malloc(size);
254  GNUNET_CRYPTO_symmetric_encrypt(&ub_plain[1],
255  ulen + slen + mdsize,
256  &skey, &iv,
257  &ub_enc[1]);
258  GNUNET_free(ub_plain);
259  ub_enc->purpose.size = htonl(ulen + slen + mdsize +
260  sizeof(struct UBlock)
261  - sizeof(struct GNUNET_CRYPTO_EcdsaSignature));
263 
264  /* derive signing-key from 'label' and public key of the namespace */
265  nsd = GNUNET_CRYPTO_ecdsa_private_key_derive(ns, label, "fs-ublock");
267  &ub_enc->verification_key);
270  &ub_enc->purpose,
271  &ub_enc->signature));
273  sizeof(ub_enc->verification_key),
274  &query);
275  GNUNET_free(nsd);
276 
278  uc->cont = cont;
279  uc->cont_cls = cont_cls;
280  if (NULL != dsh)
281  {
282  uc->qre =
284  0,
285  &query,
286  ulen + slen + mdsize + sizeof(struct UBlock),
287  ub_enc,
289  bo->content_priority,
290  bo->anonymity_level,
291  bo->replication_level,
292  bo->expiration_time,
293  -2, 1,
294  &ublock_put_cont, uc);
295  }
296  else
297  {
299  uc);
300  }
301  GNUNET_free(ub_enc);
302  return uc;
303 }
304 
305 
311 void
313 {
314  if (NULL != uc->qre)
316  if (NULL != uc->task)
318  GNUNET_free(uc);
319 }
320 
321 /* end of fs_publish_ublock.c */
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...
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.
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...
GNUNET_FS_UBlockContinuation cont
Function to call when done.
struct GNUNET_MessageHeader * msg
Definition: 005.c:2
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.
struct GNUNET_GETOPT_CommandLineOption options[]
Definition: 002.c:5
If not enough space is available, it is acceptable to only serialize some of the metadata.
uint32_t purpose
What does this signature vouch for? This must contain a GNUNET_SIGNATURE_PURPOSE_XXX constant (from g...
Master context for most FS operations.
Definition: fs_api.h:1056
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.
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
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.
static struct GNUNET_FS_UnindexContext * uc
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:75
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_().
#define GNUNET_new(type)
Allocate a struct or union of the given type.
Private ECC key encoded for transmission.
struct GNUNET_DATASTORE_QueueEntry * qre
Handle for active datastore operation.
#define GNUNET_SIGNATURE_PURPOSE_FS_UBLOCK
UBlock Signature, done using DSS, not ECC.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur...
static struct GNUNET_ARM_Handle * h
Connection with ARM.
Definition: gnunet-arm.c:94
#define _(String)
GNU gettext support macro.
Definition: platform.h:181
char * GNUNET_FS_uri_to_string(const struct GNUNET_FS_Uri *uri)
Convert a URI to a UTF-8 String.
Definition: fs_uri.c:2024
static struct GNUNET_FS_Uri * uri
Value of URI provided on command-line (when not publishing a file but just creating UBlocks to refer ...
uint32_t anonymity_level
At which anonymity level should the block be shared? (0: no anonymity, 1: normal GAP, >1: with cover traffic).
int 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:931
struct GNUNET_CRYPTO_EcdsaSignature signature
Signature using pseudonym and search keyword / identifier.
Definition: block_fs.h:54
Meta data to associate with a file, directory or namespace.
Entry in our priority queue.
Definition: datastore_api.c:96
void GNUNET_CRYPTO_hash(const void *block, size_t size, struct GNUNET_HashCode *ret)
Compute hash of a given block.
Definition: crypto_hash.c:44
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.
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:1264
an ECC signature using ECDSA
GNUNET_FS_PublishOptions
Options for publishing.
uint32_t size
How many bytes does this signature sign? (including this purpose header); in network byte order (!)...
Type of a block representing any type of search result (universal).
A 512-bit hashcode.
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:212
void GNUNET_FS_publish_ublock_cancel_(struct GNUNET_FS_PublishUblockContext *uc)
Abort UBlock publishing operation.
static unsigned int size
Size of the "table".
Definition: peer.c:66
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:241
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.
Settings for publishing a block (which may of course also apply to an entire directory or file)...
struct GNUNET_SCHEDULER_Task * task
Task to run continuation asynchronously.
static struct GNUNET_NAMESTORE_Handle * ns
Handle to the namestore.
uint32_t replication_level
How often should we try to migrate the block to other peers? Only used if "CONTENT_PUSHING" is set to...
void GNUNET_DATASTORE_cancel(struct GNUNET_DATASTORE_QueueEntry *qe)
Cancel a datastore operation.
shared definitions for the FS library
Context for &#39;ublock_put_cont&#39;.
A Universal Resource Identifier (URI), opaque.
Definition: fs_api.h:162
static struct GNUNET_CRYPTO_EddsaPublicKey pub
Definition: gnunet-scrypt.c:39
Handle to the datastore service.
static struct GNUNET_CONTAINER_MetaData * meta
Meta-data provided via command-line option.
static struct GNUNET_DATASTORE_Handle * dsh
Datastore handle.
Public ECC key (always for Curve25519) encoded in a format suitable for network transmission and ECDS...
#define GNUNET_log(kind,...)
Entry in list of pending tasks.
Definition: scheduler.c:131
uint32_t content_priority
How important is it for us to store the block? If we run out of space, the highest-priority, non-expired blocks will be kept.
Time for absolute times used by GNUnet, in microseconds.
#define GNUNET_YES
Definition: gnunet_common.h:77
static void run_cont(void *cls)
Run the continuation.
#define MAX_UBLOCK_SIZE
Maximum legal size for a ublock.
Definition: block_fs.h:41
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.
Definition: crypto_ecc.c:1296
void(* GNUNET_FS_UBlockContinuation)(void *cls, const char *emsg)
Signature of a function called as the continuation of a UBlock publication.
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.
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 * cont_cls
Closure of &#39;cont&#39;.
struct GNUNET_CRYPTO_EccSignaturePurpose purpose
What is being signed and why?
Definition: block_fs.h:59
int 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:91
struct GNUNET_CRYPTO_EcdsaPublicKey verification_key
Public key used to sign this block.
Definition: block_fs.h:64
universal block for keyword and namespace search results
Definition: block_fs.h:50
#define GNUNET_malloc(size)
Wrapper around malloc.
static struct GNUNET_FS_BlockOptions bo
Options we set for published blocks.
#define GNUNET_free(ptr)
Wrapper around free.
Merkle-tree-ish-CHK file encoding for GNUnet.
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:956
publish a UBLOCK in GNUnet