GNUnet  0.10.x
gns_api.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2009-2013, 2016, 2018 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  */
26 #include "platform.h"
27 #include "gnunet_util_lib.h"
28 #include "gnunet_constants.h"
29 #include "gnunet_arm_service.h"
30 #include "gnunet_hello_lib.h"
31 #include "gnunet_protocols.h"
32 #include "gnunet_dht_service.h"
33 #include "gns.h"
34 #include "gns_api.h"
35 
36 
37 #define LOG(kind, ...) GNUNET_log_from(kind, "gns-api", __VA_ARGS__)
38 
47 
52 
57 
62 
66  void *proc_cls;
67 
72 
76  uint32_t r_id;
77 };
78 
79 
85 static void
87 
88 
94 static void
95 reconnect_task(void *cls)
96 {
97  struct GNUNET_GNS_Handle *handle = cls;
98 
99  handle->reconnect_task = NULL;
100  reconnect(handle);
101 }
102 
103 
109 static void
111 {
112  GNUNET_MQ_destroy(handle->mq);
113  handle->mq = NULL;
114  handle->reconnect_backoff
116  handle->reconnect_task
119  handle);
120 }
121 
122 
131 static void
133  enum GNUNET_MQ_Error error)
134 {
135  struct GNUNET_GNS_Handle *handle = cls;
136 
138  "Problem with message queue. error: %i\n",
139  error);
140  force_reconnect(handle);
141 }
142 
143 
150 static int
151 check_result(void *cls,
152  const struct LookupResultMessage *lookup_msg)
153 {
154  size_t mlen = ntohs(lookup_msg->header.size) - sizeof(*lookup_msg);
155  uint32_t rd_count = ntohl(lookup_msg->rd_count);
156  struct GNUNET_GNSRECORD_Data rd[rd_count];
157 
158  (void)cls;
159  if (GNUNET_SYSERR ==
161  (const char*)&lookup_msg[1],
162  rd_count,
163  rd))
164  {
165  GNUNET_break(0);
166  return GNUNET_SYSERR;
167  }
168  return GNUNET_OK;
169 }
170 
171 
178 static void
179 handle_result(void *cls,
180  const struct LookupResultMessage *lookup_msg)
181 {
182  struct GNUNET_GNS_Handle *handle = cls;
183  size_t mlen = ntohs(lookup_msg->header.size) - sizeof(*lookup_msg);
184  uint32_t rd_count = ntohl(lookup_msg->rd_count);
185  struct GNUNET_GNSRECORD_Data rd[rd_count];
186  uint32_t r_id = ntohl(lookup_msg->id);
189  void *proc_cls;
190 
192  "Received lookup reply from GNS service (%u records)\n",
193  (unsigned int)rd_count);
194  for (lr = handle->lookup_head; NULL != lr; lr = lr->next)
195  if (lr->r_id == r_id)
196  break;
197  if (NULL == lr)
198  return;
199  proc = lr->lookup_proc;
200  proc_cls = lr->proc_cls;
201 
204  (const char*)&lookup_msg[1],
205  rd_count,
206  rd));
207  proc(proc_cls,
208  rd_count,
209  rd);
211  handle->lookup_tail,
212  lr);
213  if (NULL != lr->env)
214  GNUNET_MQ_discard(lr->env);
215  GNUNET_free(lr);
216 }
217 
218 
224 static void
226 {
227  struct GNUNET_MQ_MessageHandler handlers[] = {
230  struct LookupResultMessage,
231  handle),
233  };
234 
235  GNUNET_assert(NULL == handle->mq);
237  "Trying to connect to GNS\n");
238  handle->mq = GNUNET_CLIENT_connect(handle->cfg,
239  "gns",
240  handlers,
242  handle);
243  if (NULL == handle->mq)
244  return;
245  for (struct GNUNET_GNS_LookupRequest *lh = handle->lookup_head;
246  NULL != lh;
247  lh = lh->next)
248  GNUNET_MQ_send_copy(handle->mq,
249  lh->env);
250 }
251 
252 
259 struct GNUNET_GNS_Handle *
261 {
262  struct GNUNET_GNS_Handle *handle;
263 
264  handle = GNUNET_new(struct GNUNET_GNS_Handle);
265  handle->cfg = cfg;
266  reconnect(handle);
267  if (NULL == handle->mq)
268  {
269  GNUNET_free(handle);
270  return NULL;
271  }
272  return handle;
273 }
274 
275 
281 void
283 {
284  if (NULL != handle->mq)
285  {
286  GNUNET_MQ_destroy(handle->mq);
287  handle->mq = NULL;
288  }
289  if (NULL != handle->reconnect_task)
290  {
292  handle->reconnect_task = NULL;
293  }
294  GNUNET_assert(NULL == handle->lookup_head);
295  GNUNET_free(handle);
296 }
297 
298 
305 void *
307 {
308  struct GNUNET_GNS_Handle *handle = lr->gns_handle;
309  void *ret;
310 
312  handle->lookup_tail,
313  lr);
314  GNUNET_MQ_discard(lr->env);
315  ret = lr->proc_cls;
316  GNUNET_free(lr);
317  return ret;
318 }
319 
320 
335  const char *name,
336  const struct GNUNET_CRYPTO_EcdsaPublicKey *zone,
337  uint32_t type,
340  void *proc_cls)
341 {
342  /* IPC to shorten gns names, return shorten_handle */
343  struct LookupMessage *lookup_msg;
345  size_t nlen;
346 
347  if (NULL == name)
348  {
349  GNUNET_break(0);
350  return NULL;
351  }
353  "Trying to lookup `%s' in GNS\n",
354  name);
355  nlen = strlen(name) + 1;
356  if (nlen >= GNUNET_MAX_MESSAGE_SIZE - sizeof(*lr))
357  {
358  GNUNET_break(0);
359  return NULL;
360  }
362  lr->gns_handle = handle;
363  lr->lookup_proc = proc;
364  lr->proc_cls = proc_cls;
365  lr->r_id = handle->r_id_gen++;
366  lr->env = GNUNET_MQ_msg_extra(lookup_msg,
367  nlen,
369  lookup_msg->id = htonl(lr->r_id);
370  lookup_msg->options = htons((uint16_t)options);
371  lookup_msg->zone = *zone;
372  lookup_msg->type = htonl(type);
373  GNUNET_memcpy(&lookup_msg[1],
374  name,
375  nlen);
377  handle->lookup_tail,
378  lr);
379  if (NULL != handle->mq)
380  GNUNET_MQ_send_copy(handle->mq,
381  lr->env);
382  return lr;
383 }
384 
385 
386 /* end of gns_api.c */
uint32_t r_id
request id
Definition: gns_api.c:76
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
Connection to the GNS service.
Definition: gns_api.h:35
Message from client to GNS service to lookup records.
Definition: gns.h:36
const struct GNUNET_CONFIGURATION_Handle * cfg
Configuration to use.
Definition: gns_api.h:39
Message from GNS service to client: new results.
Definition: gns.h:75
uint32_t id
Unique identifier for this request (for key collisions).
Definition: gns.h:45
struct GNUNET_GNS_Handle * gns_handle
handle to gns
Definition: gns_api.c:56
uint32_t rd_count
The number of records contained in response.
Definition: gns.h:89
#define GNUNET_CONTAINER_DLL_insert(head, tail, element)
Insert an element at the head of a DLL.
void(* GNUNET_GNS_LookupResultProcessor)(void *cls, uint32_t rd_count, const struct GNUNET_GNSRECORD_Data *rd)
Iterator called on obtained result for a GNS lookup.
static struct GNUNET_GNS_LookupWithTldRequest * lr
Handle to lookup request.
Definition: gnunet-gns.c:75
struct GNUNET_GETOPT_CommandLineOption options[]
Definition: 002.c:5
struct GNUNET_MQ_Handle * GNUNET_CLIENT_connect(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *service_name, const struct GNUNET_MQ_MessageHandler *handlers, GNUNET_MQ_ErrorHandler error_handler, void *error_handler_cls)
Create a message queue to connect to a GNUnet service.
Definition: client.c:900
struct GNUNET_CRYPTO_EcdsaPublicKey zone
Zone that is to be used for lookup.
Definition: gns.h:50
GNUNET_MQ_Error
Error codes for the queue.
#define GNUNET_MESSAGE_TYPE_GNS_LOOKUP
Client would like to resolve a name.
struct GNUNET_GNS_LookupRequest * next
DLL.
Definition: gns_api.c:46
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
struct GNUNET_TIME_Relative reconnect_backoff
How long do we wait until we try to reconnect?
Definition: gns_api.h:64
shared data structures of libgnunetgns
Handle to a lookup request.
Definition: gns_api.c:42
#define GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT
Service response to name resolution request from client.
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
GNUNET_GNS_LocalOptions
Options for the GNS lookup.
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:75
int32_t type
the type of record to look up
Definition: gns.h:66
#define GNUNET_new(type)
Allocate a struct or union of the given type.
int GNUNET_GNSRECORD_records_deserialize(size_t len, const char *src, unsigned int rd_count, struct GNUNET_GNSRECORD_Data *dest)
Deserialize the given records to the given destination.
GNUNET_GNS_LookupResultProcessor lookup_proc
processor to call on lookup result
Definition: gns_api.c:61
uint16_t size
The length of the struct (in bytes, including the length field itself), in big-endian format...
static int ret
Final status code.
Definition: gnunet-arm.c:89
IPC messages between GNS API and GNS service.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur...
static char * zone
Name of the zone we manage.
#define GNUNET_MQ_msg_extra(mvar, esize, type)
Allocate an envelope, with extra space allocated after the space needed by the message struct...
Definition: gnunet_mq_lib.h:52
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_delayed(struct GNUNET_TIME_Relative delay, GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run with a specified delay.
Definition: scheduler.c:1237
uint32_t id
Unique identifier for this request (for key collisions).
Definition: gns.h:84
#define GNUNET_MQ_hd_var_size(name, code, str, ctx)
void GNUNET_GNS_disconnect(struct GNUNET_GNS_Handle *handle)
Shutdown connection with the GNS service.
Definition: gns_api.c:282
struct GNUNET_MQ_Handle * mq
Connection to service (if available).
Definition: gns_api.h:44
static struct GNUNET_DNS_Handle * handle
Handle to transport service.
static int result
Global testing status.
static void force_reconnect(struct GNUNET_GNS_Handle *handle)
Disconnect from service and then reconnect.
Definition: gns_api.c:110
static void reconnect(struct GNUNET_GNS_Handle *handle)
Reconnect to GNS service.
Definition: gns_api.c:225
struct GNUNET_GNS_Handle * GNUNET_GNS_connect(const struct GNUNET_CONFIGURATION_Handle *cfg)
Initialize the connection with the GNS service.
Definition: gns_api.c:260
struct GNUNET_GNS_LookupRequest * lookup_tail
Tail of linked list of active lookup requests.
Definition: gns_api.h:54
struct GNUNET_GNS_LookupRequest * prev
DLL.
Definition: gns_api.c:51
Message handler for a specific message type.
int16_t options
Local options for where to look for results (an enum GNUNET_GNS_LocalOptions in NBO).
Definition: gns.h:56
void GNUNET_MQ_discard(struct GNUNET_MQ_Envelope *mqm)
Discard the message queue message, free all allocated resources.
Definition: mq.c:319
static struct GNUNET_CONFIGURATION_Handle * cfg
Our configuration.
Definition: gnunet-arm.c:104
struct GNUNET_MQ_Envelope * env
Envelope with the message for this queue entry.
Definition: gns_api.c:71
#define GNUNET_SYSERR
Definition: gnunet_common.h:76
static int check_result(void *cls, const struct LookupResultMessage *lookup_msg)
Check validity of message received from the GNS service.
Definition: gns_api.c:151
const char * name
static void reconnect_task(void *cls)
Reconnect to GNS.
Definition: gns_api.c:95
struct GNUNET_MessageHeader header
Header of type GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT.
Definition: gns.h:79
#define GNUNET_TIME_STD_BACKOFF(r)
Perform our standard exponential back-off calculation, starting at 1 ms and then going by a factor of...
struct GNUNET_GNS_LookupRequest * lookup_head
Head of linked list of active lookup requests.
Definition: gns_api.h:49
#define LOG(kind,...)
Definition: gns_api.c:37
#define GNUNET_MAX_MESSAGE_SIZE
Largest supported message (to be precise, one byte more than the largest possible message...
configuration data
Definition: configuration.c:83
Public ECC key (always for Curve25519) encoded in a format suitable for network transmission and ECDS...
void GNUNET_MQ_send_copy(struct GNUNET_MQ_Handle *mq, const struct GNUNET_MQ_Envelope *ev)
Send a copy of a message with the given message queue.
Definition: mq.c:430
uint32_t r_id_gen
Request Id generator.
Definition: gns_api.h:69
void * GNUNET_GNS_lookup_cancel(struct GNUNET_GNS_LookupRequest *lr)
Cancel pending lookup request.
Definition: gns_api.c:306
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model
void GNUNET_MQ_destroy(struct GNUNET_MQ_Handle *mq)
Destroy the message queue.
Definition: mq.c:821
static void mq_error_handler(void *cls, enum GNUNET_MQ_Error error)
Generic error handler, called with the appropriate error code and the same closure specified at the c...
Definition: gns_api.c:132
struct GNUNET_GNS_LookupRequest * GNUNET_GNS_lookup(struct GNUNET_GNS_Handle *handle, const char *name, const struct GNUNET_CRYPTO_EcdsaPublicKey *zone, uint32_t type, enum GNUNET_GNS_LocalOptions options, GNUNET_GNS_LookupResultProcessor proc, void *proc_cls)
Perform an asynchronous lookup operation on the GNS.
Definition: gns_api.c:334
static void handle_result(void *cls, const struct LookupResultMessage *lookup_msg)
Handler for messages received from the GNS service.
Definition: gns_api.c:179
struct GNUNET_SCHEDULER_Task * reconnect_task
Reconnect task.
Definition: gns_api.h:59
#define GNUNET_MQ_handler_end()
End-marker for the handlers array.
void * proc_cls
lookup_proc closure
Definition: gns_api.c:66
#define GNUNET_free(ptr)
Wrapper around free.
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:956