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22 * @file namestore/namestore_api_monitor.c
23 * @brief API to monitor changes in the NAMESTORE
24 * @author Christian Grothoff
28 #include "gnunet_util_lib.h"
29 #include "gnunet_crypto_lib.h"
30 #include "gnunet_constants.h"
31 #include "gnunet_dnsparser_lib.h"
32 #include "gnunet_arm_service.h"
33 #include "gnunet_signatures.h"
34 #include "gnunet_namestore_service.h"
35 #include "namestore.h"
39 * Handle for a monitoring activity.
41 struct GNUNET_NAMESTORE_ZoneMonitor
44 * Configuration (to reconnect).
46 const struct GNUNET_CONFIGURATION_Handle *cfg;
49 * Handle to namestore service.
51 struct GNUNET_MQ_Handle *mq;
54 * Function to call on errors.
56 GNUNET_SCHEDULER_TaskCallback error_cb;
59 * Closure for @e error_cb.
64 * Function to call on events.
66 GNUNET_NAMESTORE_RecordMonitor monitor;
69 * Closure for @e monitor.
74 * Function called when we've synchronized.
76 GNUNET_SCHEDULER_TaskCallback sync_cb;
79 * Closure for @e sync_cb.
86 struct GNUNET_CRYPTO_EcdsaPrivateKey zone;
89 * Do we first iterate over all existing records?
97 * Reconnect to the namestore service.
99 * @param zm monitor to reconnect
102 reconnect (struct GNUNET_NAMESTORE_ZoneMonitor *zm);
106 * Handle SYNC message from the namestore service.
108 * @param cls the monitor
109 * @param msg the sync message
112 handle_sync (void *cls,
113 const struct GNUNET_MessageHeader *msg)
115 struct GNUNET_NAMESTORE_ZoneMonitor *zm = cls;
119 if (NULL != zm->sync_cb)
120 zm->sync_cb (zm->sync_cb_cls);
125 * We've received a notification about a change to our zone.
126 * Check that it is well-formed.
128 * @param cls the zone monitor handle
129 * @param lrm the message from the service.
132 check_result (void *cls,
133 const struct RecordResultMessage *lrm)
140 const char *name_tmp;
141 const char *rd_ser_tmp;
144 lrm_len = ntohs (lrm->gns_header.header.size);
145 rd_len = ntohs (lrm->rd_len);
146 rd_count = ntohs (lrm->rd_count);
147 name_len = ntohs (lrm->name_len);
148 exp_lrm_len = sizeof (struct RecordResultMessage) + name_len + rd_len;
149 if (lrm_len != exp_lrm_len)
152 return GNUNET_SYSERR;
157 return GNUNET_SYSERR;
159 name_tmp = (const char *) &lrm[1];
160 if ((name_tmp[name_len -1] != '\0') || (name_len > MAX_NAME_LEN))
163 return GNUNET_SYSERR;
165 rd_ser_tmp = (const char *) &name_tmp[name_len];
167 struct GNUNET_GNSRECORD_Data rd[rd_count];
170 GNUNET_GNSRECORD_records_deserialize (rd_len,
176 return GNUNET_SYSERR;
184 * We've received a notification about a change to our zone.
185 * Forward to monitor callback.
187 * @param cls the zone monitor handle
188 * @param lrm the message from the service.
191 handle_result (void *cls,
192 const struct RecordResultMessage *lrm)
194 struct GNUNET_NAMESTORE_ZoneMonitor *zm = cls;
198 const char *name_tmp;
199 const char *rd_ser_tmp;
201 rd_len = ntohs (lrm->rd_len);
202 rd_count = ntohs (lrm->rd_count);
203 name_len = ntohs (lrm->name_len);
204 name_tmp = (const char *) &lrm[1];
205 rd_ser_tmp = (const char *) &name_tmp[name_len];
207 struct GNUNET_GNSRECORD_Data rd[rd_count];
209 GNUNET_assert (GNUNET_OK ==
210 GNUNET_GNSRECORD_records_deserialize (rd_len,
214 zm->monitor (zm->monitor_cls,
224 * Generic error handler, called with the appropriate error code and
225 * the same closure specified at the creation of the message queue.
226 * Not every message queue implementation supports an error handler.
228 * @param cls closure with the `struct GNUNET_NAMESTORE_ZoneMonitor *`
229 * @param error error code
232 mq_error_handler (void *cls,
233 enum GNUNET_MQ_Error error)
235 struct GNUNET_NAMESTORE_ZoneMonitor *zm = cls;
243 * Reconnect to the namestore service.
245 * @param zm monitor to reconnect
248 reconnect (struct GNUNET_NAMESTORE_ZoneMonitor *zm)
250 struct GNUNET_MQ_MessageHandler handlers[] = {
251 GNUNET_MQ_hd_fixed_size (sync,
252 GNUNET_MESSAGE_TYPE_NAMESTORE_MONITOR_SYNC,
253 struct GNUNET_MessageHeader,
255 GNUNET_MQ_hd_var_size (result,
256 GNUNET_MESSAGE_TYPE_NAMESTORE_RECORD_RESULT,
257 struct RecordResultMessage,
259 GNUNET_MQ_handler_end ()
261 struct GNUNET_MQ_Envelope *env;
262 struct ZoneMonitorStartMessage *sm;
266 GNUNET_MQ_destroy (zm->mq);
267 zm->error_cb (zm->error_cb_cls);
269 zm->mq = GNUNET_CLIENT_connect (zm->cfg,
276 env = GNUNET_MQ_msg (sm,
277 GNUNET_MESSAGE_TYPE_NAMESTORE_MONITOR_START);
278 sm->iterate_first = htonl (zm->iterate_first);
280 GNUNET_MQ_send (zm->mq,
287 * Begin monitoring a zone for changes. If @a iterate_first is set,
288 * we Will first call the @a monitor function on all existing records
289 * in the selected zone(s). In any case, we will call @a sync and
290 * afterwards call @a monitor whenever a record changes.
292 * @param cfg configuration to use to connect to namestore
293 * @param zone zone to monitor
294 * @param iterate_first #GNUNET_YES to first iterate over all existing records,
295 * #GNUNET_NO to only return changes that happen from now on
296 * @param error_cb function to call on error (i.e. disconnect); note that
297 * unlike the other error callbacks in this API, a call to this
298 * function does NOT destroy the monitor handle, it merely signals
299 * that monitoring is down. You need to still explicitly call
300 * #GNUNET_NAMESTORE_zone_monitor_stop().
301 * @param error_cb_cls closure for @a error_cb
302 * @param monitor function to call on zone changes
303 * @param monitor_cls closure for @a monitor
304 * @param sync_cb function called when we're in sync with the namestore
305 * @param cls closure for @a sync_cb
306 * @return handle to stop monitoring
308 struct GNUNET_NAMESTORE_ZoneMonitor *
309 GNUNET_NAMESTORE_zone_monitor_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
310 const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone,
312 GNUNET_SCHEDULER_TaskCallback error_cb,
314 GNUNET_NAMESTORE_RecordMonitor monitor,
316 GNUNET_SCHEDULER_TaskCallback sync_cb,
319 struct GNUNET_NAMESTORE_ZoneMonitor *zm;
321 zm = GNUNET_new (struct GNUNET_NAMESTORE_ZoneMonitor);
324 zm->iterate_first = iterate_first;
325 zm->error_cb = error_cb;
326 zm->error_cb_cls = error_cb_cls;
327 zm->monitor = monitor;
328 zm->monitor_cls = monitor_cls;
329 zm->sync_cb = sync_cb;
330 zm->sync_cb_cls = sync_cb_cls;
343 * Stop monitoring a zone for changes.
345 * @param zm handle to the monitor activity to stop
348 GNUNET_NAMESTORE_zone_monitor_stop (struct GNUNET_NAMESTORE_ZoneMonitor *zm)
352 GNUNET_MQ_destroy (zm->mq);
358 /* end of namestore_api_monitor.c */