/**
* @file dht/gnunet-service-dht_clients.c
* @brief GNUnet DHT service's client management code
- * @author Supriti Singh
+ * @author Christian Grothoff
+ * @author Nathan Evans
*/
#include "platform.h"
#include "gnunet-service-xdht_neighbours.h"
#include "dht.h"
+
+/**
+ * Should routing details be logged to stderr (for debugging)?
+ */
+#define LOG_TRAFFIC(kind,...) GNUNET_log_from (kind, "dht-traffic",__VA_ARGS__)
+
+#define LOG(kind,...) GNUNET_log_from (kind, "dht-clients",__VA_ARGS__)
+
/**
* Linked list of messages to send to clients.
*/
};
+
/**
* Struct containing information about a client,
* handle to connect to it, and any pending messages
};
+/**
+ * Entry in the local forwarding map for a client's GET request.
+ */
+struct ClientQueryRecord
+{
+
+ /**
+ * The key this request was about
+ */
+ struct GNUNET_HashCode key;
+
+ /**
+ * Client responsible for the request.
+ */
+ struct ClientList *client;
+
+ /**
+ * Extended query (see gnunet_block_lib.h), allocated at the end of this struct.
+ */
+ const void *xquery;
+
+ /**
+ * Replies we have already seen for this request.
+ */
+ struct GNUNET_HashCode *seen_replies;
+
+ /**
+ * Pointer to this nodes heap location in the retry-heap (for fast removal)
+ */
+ struct GNUNET_CONTAINER_HeapNode *hnode;
+
+ /**
+ * What's the delay between re-try operations that we currently use for this
+ * request?
+ */
+ struct GNUNET_TIME_Relative retry_frequency;
+
+ /**
+ * What's the next time we should re-try this request?
+ */
+ struct GNUNET_TIME_Absolute retry_time;
+
+ /**
+ * The unique identifier of this request
+ */
+ uint64_t unique_id;
+
+ /**
+ * Number of bytes in xquery.
+ */
+ size_t xquery_size;
+
+ /**
+ * Number of entries in 'seen_replies'.
+ */
+ unsigned int seen_replies_count;
+
+ /**
+ * Desired replication level
+ */
+ uint32_t replication;
+
+ /**
+ * Any message options for this request
+ */
+ uint32_t msg_options;
+
+ /**
+ * The type for the data for the GET request.
+ */
+ enum GNUNET_BLOCK_Type type;
+
+};
+
+
+/**
+ * Struct containing paremeters of monitoring requests.
+ */
+struct ClientMonitorRecord
+{
+
+ /**
+ * Next element in DLL.
+ */
+ struct ClientMonitorRecord *next;
+
+ /**
+ * Previous element in DLL.
+ */
+ struct ClientMonitorRecord *prev;
+
+ /**
+ * Type of blocks that are of interest
+ */
+ enum GNUNET_BLOCK_Type type;
+
+ /**
+ * Key of data of interest, NULL for all.
+ */
+ struct GNUNET_HashCode *key;
+
+ /**
+ * Flag whether to notify about GET messages.
+ */
+ int16_t get;
+
+ /**
+ * Flag whether to notify about GET_REPONSE messages.
+ */
+ int16_t get_resp;
+
+ /**
+ * Flag whether to notify about PUT messages.
+ */
+ uint16_t put;
+
+ /**
+ * Client to notify of these requests.
+ */
+ struct ClientList *client;
+};
+
+
/**
* List of active clients.
*/
*/
static struct ClientList *client_tail;
+/**
+ * List of active monitoring requests.
+ */
+static struct ClientMonitorRecord *monitor_head;
+
+/**
+ * List of active monitoring requests.
+ */
+static struct ClientMonitorRecord *monitor_tail;
+
+/**
+ * Hashmap for fast key based lookup, maps keys to `struct ClientQueryRecord` entries.
+ */
+static struct GNUNET_CONTAINER_MultiHashMap *forward_map;
+
+/**
+ * Heap with all of our client's request, sorted by retry time (earliest on top).
+ */
+static struct GNUNET_CONTAINER_Heap *retry_heap;
+
+/**
+ * Task that re-transmits requests (using retry_heap).
+ */
+static GNUNET_SCHEDULER_TaskIdentifier retry_task;
+
+
/**
* Task run to check for messages that need to be sent to a client.
*
* @param client a ClientList, containing the client and any messages to be sent to it
*/
-static void process_pending_messages (struct ClientList *client);
+static void
+process_pending_messages (struct ClientList *client);
+
+
/**
* Callback called as a result of issuing a GNUNET_SERVER_notify_transmit_ready
* request. A ClientList is passed as closure, take the head of the list
process_pending_messages (client);
}
+
+/**
+ * Closure for 'forward_reply'
+ */
+struct ForwardReplyContext
+{
+
+ /**
+ * Actual message to send to matching clients.
+ */
+ struct PendingMessage *pm;
+
+ /**
+ * Embedded payload.
+ */
+ const void *data;
+
+ /**
+ * Type of the data.
+ */
+ enum GNUNET_BLOCK_Type type;
+
+ /**
+ * Number of bytes in data.
+ */
+ size_t data_size;
+
+ /**
+ * Do we need to copy 'pm' because it was already used?
+ */
+ int do_copy;
+
+};
+
+
/**
* Find a client if it exists, add it otherwise.
*
/**
- * SUPU: Call made from dht_api.c
- * Handler for monitor stop messages
+ * Iterator over hash map entries that frees all entries
+ * associated with the given client.
*
- * @param cls closure for the service
- * @param client the client we received this message from
- * @param message the actual message received
+ * @param cls client to search for in source routes
+ * @param key current key code (ignored)
+ * @param value value in the hash map, a ClientQueryRecord
+ * @return #GNUNET_YES (we should continue to iterate)
+ */
+static int
+remove_client_records (void *cls, const struct GNUNET_HashCode * key, void *value)
+{
+ struct ClientList *client = cls;
+ struct ClientQueryRecord *record = value;
+
+ if (record->client != client)
+ return GNUNET_YES;
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Removing client %p's record for key %s\n", client,
+ GNUNET_h2s (key));
+ GNUNET_assert (GNUNET_YES ==
+ GNUNET_CONTAINER_multihashmap_remove (forward_map, key,
+ record));
+ if (NULL != record->hnode)
+ GNUNET_CONTAINER_heap_remove_node (record->hnode);
+ GNUNET_array_grow (record->seen_replies, record->seen_replies_count, 0);
+ GNUNET_free (record);
+ return GNUNET_YES;
+}
+
+
+/**
+ * Iterator over hash map entries that send a given reply to
+ * each of the matching clients. With some tricky recycling
+ * of the buffer.
*
+ * @param cls the 'struct ForwardReplyContext'
+ * @param key current key
+ * @param value value in the hash map, a ClientQueryRecord
+ * @return GNUNET_YES (we should continue to iterate),
+ * if the result is mal-formed, GNUNET_NO
*/
-static void
-handle_dht_local_monitor_stop (void *cls, struct GNUNET_SERVER_Client *client,
- const struct GNUNET_MessageHeader *message)
+static int
+forward_reply (void *cls, const struct GNUNET_HashCode * key, void *value)
{
- //const struct GNUNET_DHT_MonitorStartStopMessage *msg;
+ struct ForwardReplyContext *frc = cls;
+ struct ClientQueryRecord *record = value;
+ struct PendingMessage *pm;
+ struct GNUNET_DHT_ClientResultMessage *reply;
+ enum GNUNET_BLOCK_EvaluationResult eval;
+ int do_free;
+ struct GNUNET_HashCode ch;
+ unsigned int i;
+
+ LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG,
+ "R5N CLIENT-RESULT %s\n",
+ GNUNET_h2s_full (key));
+ if ((record->type != GNUNET_BLOCK_TYPE_ANY) && (record->type != frc->type))
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Record type missmatch, not passing request for key %s to local client\n",
+ GNUNET_h2s (key));
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop
+ ("# Key match, type mismatches in REPLY to CLIENT"),
+ 1, GNUNET_NO);
+ return GNUNET_YES; /* type mismatch */
+ }
+ GNUNET_CRYPTO_hash (frc->data, frc->data_size, &ch);
+ for (i = 0; i < record->seen_replies_count; i++)
+ if (0 == memcmp (&record->seen_replies[i], &ch, sizeof (struct GNUNET_HashCode)))
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Duplicate reply, not passing request for key %s to local client\n",
+ GNUNET_h2s (key));
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop
+ ("# Duplicate REPLIES to CLIENT request dropped"),
+ 1, GNUNET_NO);
+ return GNUNET_YES; /* duplicate */
+ }
+ eval =
+ GNUNET_BLOCK_evaluate (GDS_block_context, record->type, key, NULL, 0,
+ record->xquery, record->xquery_size, frc->data,
+ frc->data_size);
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Evaluation result is %d for key %s for local client's query\n",
+ (int) eval, GNUNET_h2s (key));
+ switch (eval)
+ {
+ case GNUNET_BLOCK_EVALUATION_OK_LAST:
+ do_free = GNUNET_YES;
+ break;
+ case GNUNET_BLOCK_EVALUATION_OK_MORE:
+ GNUNET_array_append (record->seen_replies, record->seen_replies_count, ch);
+ do_free = GNUNET_NO;
+ break;
+ case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
+ /* should be impossible to encounter here */
+ GNUNET_break (0);
+ return GNUNET_YES;
+ case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
+ GNUNET_break_op (0);
+ return GNUNET_NO;
+ case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
+ GNUNET_break (0);
+ return GNUNET_NO;
+ case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
+ GNUNET_break (0);
+ return GNUNET_NO;
+ case GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT:
+ return GNUNET_YES;
+ case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Unsupported block type (%u) in request!\n"), record->type);
+ return GNUNET_NO;
+ default:
+ GNUNET_break (0);
+ return GNUNET_NO;
+ }
+ if (GNUNET_NO == frc->do_copy)
+ {
+ /* first time, we can use the original data */
+ pm = frc->pm;
+ frc->do_copy = GNUNET_YES;
+ }
+ else
+ {
+ /* two clients waiting for same reply, must copy for queueing */
+ pm = GNUNET_malloc (sizeof (struct PendingMessage) +
+ ntohs (frc->pm->msg->size));
+ memcpy (pm, frc->pm,
+ sizeof (struct PendingMessage) + ntohs (frc->pm->msg->size));
+ pm->next = pm->prev = NULL;
+ pm->msg = (struct GNUNET_MessageHeader *) &pm[1];
+ }
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop ("# RESULTS queued for clients"), 1,
+ GNUNET_NO);
+ reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
+ reply->unique_id = record->unique_id;
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Queueing reply to query %s for client %p\n",
+ GNUNET_h2s (key),
+ record->client->client_handle);
+ add_pending_message (record->client, pm);
+ if (GNUNET_YES == do_free)
+ remove_client_records (record->client, key, record);
+ return GNUNET_YES;
}
/**
- * SUPU: Monitor call made from dht_api.c
- * Handler for monitor start messages
+ * Handle a reply we've received from another peer. If the reply
+ * matches any of our pending queries, forward it to the respective
+ * client(s).
*
- * @param cls closure for the service
- * @param client the client we received this message from
- * @param message the actual message received
+ * @param expiration when will the reply expire
+ * @param key the query this reply is for
+ * @param get_path_length number of peers in @a get_path
+ * @param get_path path the reply took on get
+ * @param put_path_length number of peers in @a put_path
+ * @param put_path path the reply took on put
+ * @param type type of the reply
+ * @param data_size number of bytes in @a data
+ * @param data application payload data
+ */
+void
+GDS_CLIENTS_handle_reply (struct GNUNET_TIME_Absolute expiration,
+ const struct GNUNET_HashCode *key,
+ unsigned int get_path_length,
+ const struct GNUNET_PeerIdentity *get_path,
+ unsigned int put_path_length,
+ const struct GNUNET_PeerIdentity *put_path,
+ enum GNUNET_BLOCK_Type type, size_t data_size,
+ const void *data)
+{
+ struct ForwardReplyContext frc;
+ struct PendingMessage *pm;
+ struct GNUNET_DHT_ClientResultMessage *reply;
+ struct GNUNET_PeerIdentity *paths;
+ size_t msize;
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "reply for key %s\n",
+ GNUNET_h2s (key));
+
+ if (NULL == GNUNET_CONTAINER_multihashmap_get (forward_map, key))
+ {
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop
+ ("# REPLIES ignored for CLIENTS (no match)"), 1,
+ GNUNET_NO);
+ return; /* no matching request, fast exit! */
+ }
+ msize =
+ sizeof (struct GNUNET_DHT_ClientResultMessage) + data_size +
+ (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity);
+ if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Could not pass reply to client, message too big!\n"));
+ return;
+ }
+ pm = GNUNET_malloc (msize + sizeof (struct PendingMessage));
+ reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
+ pm->msg = &reply->header;
+ reply->header.size = htons ((uint16_t) msize);
+ reply->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CLIENT_RESULT);
+ reply->type = htonl (type);
+ reply->get_path_length = htonl (get_path_length);
+ reply->put_path_length = htonl (put_path_length);
+ reply->unique_id = 0; /* filled in later */
+ reply->expiration = GNUNET_TIME_absolute_hton (expiration);
+ reply->key = *key;
+ paths = (struct GNUNET_PeerIdentity *) &reply[1];
+ memcpy (paths, put_path,
+ sizeof (struct GNUNET_PeerIdentity) * put_path_length);
+ memcpy (&paths[put_path_length], get_path,
+ sizeof (struct GNUNET_PeerIdentity) * get_path_length);
+ memcpy (&paths[get_path_length + put_path_length], data, data_size);
+ frc.do_copy = GNUNET_NO;
+ frc.pm = pm;
+ frc.data = data;
+ frc.data_size = data_size;
+ frc.type = type;
+ GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, key, &forward_reply,
+ &frc);
+
+ if (GNUNET_NO == frc.do_copy)
+ {
+ /* did not match any of the requests, free! */
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop
+ ("# REPLIES ignored for CLIENTS (no match)"), 1,
+ GNUNET_NO);
+ GNUNET_free (pm);
+ }
+}
+
+/**
+ * Check if some client is monitoring GET messages and notify
+ * them in that case.
*
+ * @param options Options, for instance RecordRoute, DemultiplexEverywhere.
+ * @param type The type of data in the request.
+ * @param hop_count Hop count so far.
+ * @param path_length number of entries in path (or 0 if not recorded).
+ * @param path peers on the GET path (or NULL if not recorded).
+ * @param desired_replication_level Desired replication level.
+ * @param key Key of the requested data.
*/
-static void
-handle_dht_local_monitor (void *cls, struct GNUNET_SERVER_Client *client,
- const struct GNUNET_MessageHeader *message)
+void
+GDS_CLIENTS_process_get (uint32_t options,
+ enum GNUNET_BLOCK_Type type,
+ uint32_t hop_count,
+ uint32_t desired_replication_level,
+ unsigned int path_length,
+ const struct GNUNET_PeerIdentity *path,
+ const struct GNUNET_HashCode * key)
{
- //const struct GNUNET_DHT_MonitorStartStopMessage *msg;
- /* FIXME: At the moment I don't know exact usage of monitor message. But most
- probably it will be just copy and paste from old implementation. */
+ struct ClientMonitorRecord *m;
+ struct ClientList **cl;
+ unsigned int cl_size;
+
+ cl = NULL;
+ cl_size = 0;
+ for (m = monitor_head; NULL != m; m = m->next)
+ {
+ if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
+ (NULL == m->key ||
+ memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
+ {
+ struct PendingMessage *pm;
+ struct GNUNET_DHT_MonitorGetMessage *mmsg;
+ struct GNUNET_PeerIdentity *msg_path;
+ size_t msize;
+ unsigned int i;
+
+ /* Don't send duplicates */
+ for (i = 0; i < cl_size; i++)
+ if (cl[i] == m->client)
+ break;
+ if (i < cl_size)
+ continue;
+ GNUNET_array_append (cl, cl_size, m->client);
+
+ msize = path_length * sizeof (struct GNUNET_PeerIdentity);
+ msize += sizeof (struct GNUNET_DHT_MonitorGetMessage);
+ msize += sizeof (struct PendingMessage);
+ pm = GNUNET_malloc (msize);
+ mmsg = (struct GNUNET_DHT_MonitorGetMessage *) &pm[1];
+ pm->msg = &mmsg->header;
+ mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
+ mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET);
+ mmsg->options = htonl(options);
+ mmsg->type = htonl(type);
+ mmsg->hop_count = htonl(hop_count);
+ mmsg->desired_replication_level = htonl(desired_replication_level);
+ mmsg->get_path_length = htonl(path_length);
+ memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
+ msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1];
+ if (path_length > 0)
+ memcpy (msg_path, path,
+ path_length * sizeof (struct GNUNET_PeerIdentity));
+ add_pending_message (m->client, pm);
+ }
+ }
+ GNUNET_free_non_null (cl);
}
-/**SUPU: Call to this function is made whenever a client does not want the
- * get request any more. There is a function in dht_api.c but I don't know
- * yet how the call is made to this function.
- * Handler for any generic DHT stop messages, calls the appropriate handler
- * depending on message type (if processed locally)
- *
- * @param cls closure for the service
- * @param client the client we received this message from
- * @param message the actual message received
+/**
+ * Check if some client is monitoring PUT messages and notify
+ * them in that case.
*
+ * @param options Options, for instance RecordRoute, DemultiplexEverywhere.
+ * @param type The type of data in the request.
+ * @param hop_count Hop count so far.
+ * @param path_length number of entries in path (or 0 if not recorded).
+ * @param path peers on the PUT path (or NULL if not recorded).
+ * @param desired_replication_level Desired replication level.
+ * @param exp Expiration time of the data.
+ * @param key Key under which data is to be stored.
+ * @param data Pointer to the data carried.
+ * @param size Number of bytes in data.
+ */
+void
+GDS_CLIENTS_process_put (uint32_t options,
+ enum GNUNET_BLOCK_Type type,
+ uint32_t hop_count,
+ uint32_t desired_replication_level,
+ unsigned int path_length,
+ const struct GNUNET_PeerIdentity *path,
+ struct GNUNET_TIME_Absolute exp,
+ const struct GNUNET_HashCode * key,
+ const void *data,
+ size_t size)
+{
+ struct ClientMonitorRecord *m;
+ struct ClientList **cl;
+ unsigned int cl_size;
+
+ cl = NULL;
+ cl_size = 0;
+ for (m = monitor_head; NULL != m; m = m->next)
+ {
+ if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
+ (NULL == m->key ||
+ memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
+ {
+ struct PendingMessage *pm;
+ struct GNUNET_DHT_MonitorPutMessage *mmsg;
+ struct GNUNET_PeerIdentity *msg_path;
+ size_t msize;
+ unsigned int i;
+
+ /* Don't send duplicates */
+ for (i = 0; i < cl_size; i++)
+ if (cl[i] == m->client)
+ break;
+ if (i < cl_size)
+ continue;
+ GNUNET_array_append (cl, cl_size, m->client);
+
+ msize = size;
+ msize += path_length * sizeof (struct GNUNET_PeerIdentity);
+ msize += sizeof (struct GNUNET_DHT_MonitorPutMessage);
+ msize += sizeof (struct PendingMessage);
+ pm = GNUNET_malloc (msize);
+ mmsg = (struct GNUNET_DHT_MonitorPutMessage *) &pm[1];
+ pm->msg = (struct GNUNET_MessageHeader *) mmsg;
+ mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
+ mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_PUT);
+ mmsg->options = htonl(options);
+ mmsg->type = htonl(type);
+ mmsg->hop_count = htonl(hop_count);
+ mmsg->desired_replication_level = htonl(desired_replication_level);
+ mmsg->put_path_length = htonl(path_length);
+ msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1];
+ if (path_length > 0)
+ {
+ memcpy (msg_path, path,
+ path_length * sizeof (struct GNUNET_PeerIdentity));
+ }
+ mmsg->expiration_time = GNUNET_TIME_absolute_hton(exp);
+ memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
+ if (size > 0)
+ memcpy (&msg_path[path_length], data, size);
+ add_pending_message (m->client, pm);
+ }
+ }
+ GNUNET_free_non_null (cl);
+}
+
+
+/**
+ * Route the given request via the DHT.
*/
static void
-handle_dht_local_get_stop (void *cls, struct GNUNET_SERVER_Client *client,
- const struct GNUNET_MessageHeader *message)
+transmit_request (struct ClientQueryRecord *cqr)
{
- //const struct GNUNET_DHT_ClientGetStopMessage *dht_stop_msg;
- /* FIXME: Whats the use of get_stop. A client notifies the server to stop asking
- for the get message. But in case of x-vine, it asks for get only once. So,
- when it has already send the get message, after that if client asks it to
- stop, it really can't do anything. Its better to wait for the result, discard
- it and don't communicate with client about the result instead of generating
- more traffic.*/
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop
+ ("# GET requests from clients injected"), 1,
+ GNUNET_NO);
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Initiating GET for %s, replication %u, already have %u replies\n",
+ GNUNET_h2s (&cqr->key),
+ cqr->replication,
+ cqr->seen_replies_count);
+
+ struct GNUNET_PeerIdentity my_identity;
+ my_identity = GDS_NEIGHBOURS_get_my_id ();
+ GDS_NEIGHBOURS_send_get (&cqr->key, cqr->type, cqr->msg_options,
+ cqr->replication, my_identity, my_identity, NULL,
+ 0, 0, NULL);
+
+ /* exponential back-off for retries.
+ * max GNUNET_TIME_STD_EXPONENTIAL_BACKOFF_THRESHOLD (15 min) */
+ cqr->retry_frequency = GNUNET_TIME_STD_BACKOFF (cqr->retry_frequency);
+ cqr->retry_time = GNUNET_TIME_relative_to_absolute (cqr->retry_frequency);
}
+
/**
- * FIXME: Call to this function is made whenever we have a get request.
- * Handler for DHT GET messages from the client.
+ * Task that looks at the 'retry_heap' and transmits all of the requests
+ * on the heap that are ready for transmission. Then re-schedules
+ * itself (unless the heap is empty).
*
- * @param cls closure for the service
- * @param client the client we received this message from
- * @param message the actual message received
+ * @param cls unused
+ * @param tc scheduler context
*/
static void
-handle_dht_local_get (void *cls, struct GNUNET_SERVER_Client *client,
- const struct GNUNET_MessageHeader *message)
+transmit_next_request_task (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
{
- struct GNUNET_DHT_ClientGetMessage *get_msg;
- struct GNUNET_PeerIdentity *get_path;
- struct GNUNET_PeerIdentity *my_identity;
- unsigned int get_path_length;
- uint16_t size;
-
- size = ntohs (message->size);
- if (size < sizeof (struct GNUNET_DHT_ClientGetMessage))
- {
- GNUNET_break (0);
- GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
+ struct ClientQueryRecord *cqr;
+ struct GNUNET_TIME_Relative delay;
+
+ retry_task = GNUNET_SCHEDULER_NO_TASK;
+ if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
return;
+ while (NULL != (cqr = GNUNET_CONTAINER_heap_remove_root (retry_heap)))
+ {
+ cqr->hnode = NULL;
+ delay = GNUNET_TIME_absolute_get_remaining (cqr->retry_time);
+ if (delay.rel_value_us > 0)
+ {
+ cqr->hnode =
+ GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
+ cqr->retry_time.abs_value_us);
+ retry_task =
+ GNUNET_SCHEDULER_add_delayed (delay, &transmit_next_request_task,
+ NULL);
+ return;
+ }
+ transmit_request (cqr);
+ cqr->hnode =
+ GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
+ cqr->retry_time.abs_value_us);
}
-
- get_msg = (struct GNUNET_DHT_ClientGetMessage *) message;
-
- /* FIXME: Search locally? Why should we always search locally?
- Current implementation of datacache needs to be modified. If found here, then
- notify the requesting client. */
-
- /* FIXME: Call GDS_NEIGHBOURS_handle_get
- Here you need to remember the whole path because you need to travel that path
- and reach back here with the result. So, you should send your own id, client
- id, get path, get path length. You also need to add yourself to the get path. */
- my_identity = GDS_NEIGHBOURS_get_id();
- get_path = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
- memcpy (get_path, &my_identity, sizeof (struct GNUNET_PeerIdentity));
- get_path_length = 1;
-
- /* FIXME:
- * 1. Find some unique identifier for the client.
- * 2. Also, I don't know the usage of block, replication and type. So, I
- * am not sending the parameters now. */
- GDS_NEIGHBOURS_handle_get (my_identity, get_path, get_path_length,
- &(get_msg->key), NULL, NULL, NULL);
-
}
/**
* Handler for PUT messages.
+ *
* @param cls closure for the service
* @param client the client we received this message from
* @param message the actual message received
handle_dht_local_put (void *cls, struct GNUNET_SERVER_Client *client,
const struct GNUNET_MessageHeader *message)
{
- struct GNUNET_DHT_ClientPutMessage *put_msg;
- struct GNUNET_DHT_ClientPutConfirmationMessage *conf;
+ const struct GNUNET_DHT_ClientPutMessage *put_msg;
struct PendingMessage *pm;
- uint16_t size; /* FIXME: When to use size_t and when uint16_t */
-
+ struct GNUNET_DHT_ClientPutConfirmationMessage *conf;
+ uint16_t size;
+
size = ntohs (message->size);
if (size < sizeof (struct GNUNET_DHT_ClientPutMessage))
{
GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
return;
}
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop
+ ("# PUT requests received from clients"), 1,
+ GNUNET_NO);
+ put_msg = (const struct GNUNET_DHT_ClientPutMessage *) message;
+ LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "X-VINE DHT CLIENT-PUT %s\n",
+ GNUNET_h2s_full (&put_msg->key));
+ /* give to local clients */
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Handling local PUT of %u-bytes for query %s\n",
+ size - sizeof (struct GNUNET_DHT_ClientPutMessage),
+ GNUNET_h2s (&put_msg->key));
- /* FIXME:Should we define put_msg as const? */
- put_msg = (struct GNUNET_DHT_ClientPutMessage *) message;
-
- /* store locally. FIXME: Is it secure to allow each peer to store the data? */
+ GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (put_msg->expiration),
+ &put_msg->key, 0, NULL, 0, NULL,
+ ntohl (put_msg->type),
+ size - sizeof (struct GNUNET_DHT_ClientPutMessage),
+ &put_msg[1]);
+ /* FIXME: Should we store locally? */
GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (put_msg->expiration),
&put_msg->key, 0, NULL, ntohl (put_msg->type),
size - sizeof (struct GNUNET_DHT_ClientPutMessage),
&put_msg[1]);
+
+ struct GNUNET_PeerIdentity my_identity = GDS_NEIGHBOURS_get_my_id();
+ GDS_NEIGHBOURS_send_put (&put_msg->key,
+ ntohl (put_msg->type), ntohl (put_msg->options),
+ ntohl (put_msg->desired_replication_level),
+ my_identity, my_identity, NULL, 0, 0, NULL,
+ GNUNET_TIME_absolute_ntoh (put_msg->expiration),
+ &put_msg[1],
+ size - sizeof (struct GNUNET_DHT_ClientPutMessage));
+
+
+ GDS_CLIENTS_process_put (ntohl (put_msg->options),
+ ntohl (put_msg->type),
+ 0,
+ ntohl (put_msg->desired_replication_level),
+ 1,
+ &my_identity,
+ GNUNET_TIME_absolute_ntoh (put_msg->expiration),
+ &put_msg->key,
+ &put_msg[1],
+ size - sizeof (struct GNUNET_DHT_ClientPutMessage));
- /* FIXME: Right now I have just kept all the fields from the old function.
- It may be possible that most of them are not needed. Check and remove if
- not needed. Usage of replication, options and type is still not clear. */
- GDS_NEIGHBOURS_handle_put (ntohl (put_msg->type), ntohl (put_msg->options),
- ntohl (put_msg->desired_replication_level),
- GNUNET_TIME_absolute_ntoh (put_msg->expiration),
- 0 /* hop count */ ,
- &put_msg->key, 0, NULL, &put_msg[1],
- size -
- sizeof (struct GNUNET_DHT_ClientPutMessage),
- NULL, NULL, NULL);
-
- /* FIXME: Here we send back the confirmation before verifying if put was successful
- or not. */
pm = GNUNET_malloc (sizeof (struct PendingMessage) +
sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
conf = (struct GNUNET_DHT_ClientPutConfirmationMessage *) &pm[1];
GNUNET_SERVER_receive_done (client, GNUNET_OK);
}
+
+/**
+ * Handler for DHT GET messages from the client.
+ *
+ * @param cls closure for the service
+ * @param client the client we received this message from
+ * @param message the actual message received
+ */
+static void
+handle_dht_local_get (void *cls, struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *message)
+{
+ const struct GNUNET_DHT_ClientGetMessage *get;
+ struct ClientQueryRecord *cqr;
+ size_t xquery_size;
+ const char *xquery;
+ uint16_t size;
+
+ size = ntohs (message->size);
+ if (size < sizeof (struct GNUNET_DHT_ClientGetMessage))
+ {
+ GNUNET_break (0);
+ GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
+ return;
+ }
+ xquery_size = size - sizeof (struct GNUNET_DHT_ClientGetMessage);
+ get = (const struct GNUNET_DHT_ClientGetMessage *) message;
+ xquery = (const char *) &get[1];
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop
+ ("# GET requests received from clients"), 1,
+ GNUNET_NO);
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Received GET request for %s from local client %p, xq: %.*s\n",
+ GNUNET_h2s (&get->key), client, xquery_size, xquery);
+
+ LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "X-VINE CLIENT-GET %s\n",
+ GNUNET_h2s_full (&get->key));
+
+
+ cqr = GNUNET_malloc (sizeof (struct ClientQueryRecord) + xquery_size);
+ cqr->key = get->key;
+ cqr->client = find_active_client (client);
+ cqr->xquery = (void *) &cqr[1];
+ memcpy (&cqr[1], xquery, xquery_size);
+ cqr->hnode = GNUNET_CONTAINER_heap_insert (retry_heap, cqr, 0);
+ cqr->retry_frequency = GNUNET_TIME_UNIT_SECONDS;
+ cqr->retry_time = GNUNET_TIME_absolute_get ();
+ cqr->unique_id = get->unique_id;
+ cqr->xquery_size = xquery_size;
+ cqr->replication = ntohl (get->desired_replication_level);
+ cqr->msg_options = ntohl (get->options);
+ cqr->type = ntohl (get->type);
+ // FIXME use cqr->key, set multihashmap create to GNUNET_YES
+ GNUNET_CONTAINER_multihashmap_put (forward_map, &get->key, cqr,
+ GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
+
+ struct GNUNET_PeerIdentity my_identity;
+ my_identity = GDS_NEIGHBOURS_get_my_id();
+ GDS_CLIENTS_process_get (ntohl (get->options),
+ ntohl (get->type),
+ 0,
+ ntohl (get->desired_replication_level),
+ 1,
+ &my_identity,
+ &get->key);
+ /* start remote requests */
+ if (GNUNET_SCHEDULER_NO_TASK != retry_task)
+ GNUNET_SCHEDULER_cancel (retry_task);
+ retry_task = GNUNET_SCHEDULER_add_now (&transmit_next_request_task, NULL);
+ GNUNET_SERVER_receive_done (client, GNUNET_OK);
+}
+
+
+/**
+ * Closure for 'find_by_unique_id'.
+ */
+struct FindByUniqueIdContext
+{
+ /**
+ * Where to store the result, if found.
+ */
+ struct ClientQueryRecord *cqr;
+
+ uint64_t unique_id;
+};
+
+
+/**
+ * Function called for each existing DHT record for the given
+ * query. Checks if it matches the UID given in the closure
+ * and if so returns the entry as a result.
+ *
+ * @param cls the search context
+ * @param key query for the lookup (not used)
+ * @param value the 'struct ClientQueryRecord'
+ * @return GNUNET_YES to continue iteration (result not yet found)
+ */
+static int
+find_by_unique_id (void *cls,
+ const struct GNUNET_HashCode *key,
+ void *value)
+{
+ struct FindByUniqueIdContext *fui_ctx = cls;
+ struct ClientQueryRecord *cqr = value;
+
+ if (cqr->unique_id != fui_ctx->unique_id)
+ return GNUNET_YES;
+ fui_ctx->cqr = cqr;
+ return GNUNET_NO;
+}
+
+
+/**
+ * Handler for "GET result seen" messages from the client.
+ *
+ * @param cls closure for the service
+ * @param client the client we received this message from
+ * @param message the actual message received
+ */
+static void
+handle_dht_local_get_result_seen (void *cls, struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *message)
+{
+ const struct GNUNET_DHT_ClientGetResultSeenMessage *seen;
+ uint16_t size;
+ unsigned int hash_count;
+ unsigned int old_count;
+ const struct GNUNET_HashCode *hc;
+ struct FindByUniqueIdContext fui_ctx;
+ struct ClientQueryRecord *cqr;
+
+ size = ntohs (message->size);
+ if (size < sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage))
+ {
+ GNUNET_break (0);
+ GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
+ return;
+ }
+ seen = (const struct GNUNET_DHT_ClientGetResultSeenMessage *) message;
+ hash_count = (size - sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage)) / sizeof (struct GNUNET_HashCode);
+ if (size != sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage) + hash_count * sizeof (struct GNUNET_HashCode))
+ {
+ GNUNET_break (0);
+ GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
+ return;
+ }
+ hc = (const struct GNUNET_HashCode*) &seen[1];
+ fui_ctx.unique_id = seen->unique_id;
+ fui_ctx.cqr = NULL;
+ GNUNET_CONTAINER_multihashmap_get_multiple (forward_map,
+ &seen->key,
+ &find_by_unique_id,
+ &fui_ctx);
+ if (NULL == (cqr = fui_ctx.cqr))
+ {
+ GNUNET_break (0);
+ GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
+ return;
+ }
+ /* finally, update 'seen' list */
+ old_count = cqr->seen_replies_count;
+ GNUNET_array_grow (cqr->seen_replies,
+ cqr->seen_replies_count,
+ cqr->seen_replies_count + hash_count);
+ memcpy (&cqr->seen_replies[old_count],
+ hc,
+ sizeof (struct GNUNET_HashCode) * hash_count);
+}
+
+
+/**
+ * Closure for 'remove_by_unique_id'.
+ */
+struct RemoveByUniqueIdContext
+{
+ /**
+ * Client that issued the removal request.
+ */
+ struct ClientList *client;
+
+ /**
+ * Unique ID of the request.
+ */
+ uint64_t unique_id;
+};
+
+
+/**
+ * Iterator over hash map entries that frees all entries
+ * that match the given client and unique ID.
+ *
+ * @param cls unique ID and client to search for in source routes
+ * @param key current key code
+ * @param value value in the hash map, a ClientQueryRecord
+ * @return GNUNET_YES (we should continue to iterate)
+ */
+static int
+remove_by_unique_id (void *cls, const struct GNUNET_HashCode * key, void *value)
+{
+ const struct RemoveByUniqueIdContext *ctx = cls;
+ struct ClientQueryRecord *record = value;
+
+ if (record->unique_id != ctx->unique_id)
+ return GNUNET_YES;
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Removing client %p's record for key %s (by unique id)\n",
+ ctx->client->client_handle, GNUNET_h2s (key));
+ return remove_client_records (ctx->client, key, record);
+}
+
+
+/**
+ * Handler for any generic DHT stop messages, calls the appropriate handler
+ * depending on message type (if processed locally)
+ *
+ * @param cls closure for the service
+ * @param client the client we received this message from
+ * @param message the actual message received
+ *
+ */
+static void
+handle_dht_local_get_stop (void *cls, struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *message)
+{
+ const struct GNUNET_DHT_ClientGetStopMessage *dht_stop_msg =
+ (const struct GNUNET_DHT_ClientGetStopMessage *) message;
+ struct RemoveByUniqueIdContext ctx;
+
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop
+ ("# GET STOP requests received from clients"), 1,
+ GNUNET_NO);
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Received GET STOP request for %s from local client %p\n",
+ client, GNUNET_h2s (&dht_stop_msg->key));
+ ctx.client = find_active_client (client);
+ ctx.unique_id = dht_stop_msg->unique_id;
+ GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, &dht_stop_msg->key,
+ &remove_by_unique_id, &ctx);
+ GNUNET_SERVER_receive_done (client, GNUNET_OK);
+}
+
+
+/**
+ * Handler for monitor start messages
+ *
+ * @param cls closure for the service
+ * @param client the client we received this message from
+ * @param message the actual message received
+ *
+ */
+static void
+handle_dht_local_monitor (void *cls, struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *message)
+{
+ struct ClientMonitorRecord *r;
+ const struct GNUNET_DHT_MonitorStartStopMessage *msg;
+
+ msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
+ r = GNUNET_new (struct ClientMonitorRecord);
+
+ r->client = find_active_client(client);
+ r->type = ntohl(msg->type);
+ r->get = ntohs(msg->get);
+ r->get_resp = ntohs(msg->get_resp);
+ r->put = ntohs(msg->put);
+ if (0 == ntohs(msg->filter_key))
+ r->key = NULL;
+ else
+ {
+ r->key = GNUNET_new (struct GNUNET_HashCode);
+ memcpy (r->key, &msg->key, sizeof (struct GNUNET_HashCode));
+ }
+ GNUNET_CONTAINER_DLL_insert (monitor_head, monitor_tail, r);
+ GNUNET_SERVER_receive_done (client, GNUNET_OK);
+}
+
+
+/**
+ * Handler for monitor stop messages
+ *
+ * @param cls closure for the service
+ * @param client the client we received this message from
+ * @param message the actual message received
+ *
+ */
+static void
+handle_dht_local_monitor_stop (void *cls, struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *message)
+{
+ struct ClientMonitorRecord *r;
+ const struct GNUNET_DHT_MonitorStartStopMessage *msg;
+ int keys_match;
+
+ msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
+ r = monitor_head;
+
+ while (NULL != r)
+ {
+ if (NULL == r->key)
+ keys_match = (0 == ntohs(msg->filter_key));
+ else
+ {
+ keys_match = (0 != ntohs(msg->filter_key)
+ && !memcmp(r->key, &msg->key, sizeof(struct GNUNET_HashCode)));
+ }
+ if (find_active_client(client) == r->client
+ && ntohl(msg->type) == r->type
+ && r->get == msg->get
+ && r->get_resp == msg->get_resp
+ && r->put == msg->put
+ && keys_match
+ )
+ {
+ GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, r);
+ GNUNET_free_non_null (r->key);
+ GNUNET_free (r);
+ GNUNET_SERVER_receive_done (client, GNUNET_OK);
+ return; /* Delete only ONE entry */
+ }
+ r = r->next;
+ }
+
+ GNUNET_SERVER_receive_done (client, GNUNET_OK);
+}
+
+
/**
* Functions with this signature are called whenever a client
* is disconnected on the network level.
handle_client_disconnect (void *cls,
struct GNUNET_SERVER_Client *client)
{
- /* You should maintain a list of client attached to this service. Then
- search for the correct client and stop all its ongoing activites and
- delete it from the list. */
-}
+ struct ClientList *pos;
+ struct PendingMessage *reply;
+ struct ClientMonitorRecord *monitor;
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Local client %p disconnects\n",
+ client);
+ pos = find_active_client (client);
+ GNUNET_CONTAINER_DLL_remove (client_head, client_tail, pos);
+ if (pos->transmit_handle != NULL)
+ GNUNET_SERVER_notify_transmit_ready_cancel (pos->transmit_handle);
+ while (NULL != (reply = pos->pending_head))
+ {
+ GNUNET_CONTAINER_DLL_remove (pos->pending_head, pos->pending_tail, reply);
+ GNUNET_free (reply);
+ }
+ monitor = monitor_head;
+ while (NULL != monitor)
+ {
+ if (monitor->client == pos)
+ {
+ struct ClientMonitorRecord *next;
-/**
- * Get result from neighbours file.
- */
-void
-GDS_CLIENTS_process_get_result()
-{
-
+ GNUNET_free_non_null (monitor->key);
+ next = monitor->next;
+ GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, monitor);
+ GNUNET_free (monitor);
+ monitor = next;
+ }
+ else
+ monitor = monitor->next;
+ }
+ GNUNET_CONTAINER_multihashmap_iterate (forward_map, &remove_client_records,
+ pos);
+ GNUNET_free (pos);
}
+
/**
- * SUPU: Call to this function is made from gnunet-service-xdht.c
- * Here we register handlers for each possible kind of message the service
- * receives from the clients.
* Initialize client subsystem.
*
* @param server the initialized server
{&handle_dht_local_monitor_stop, NULL,
GNUNET_MESSAGE_TYPE_DHT_MONITOR_STOP,
sizeof (struct GNUNET_DHT_MonitorStartStopMessage)},
+ {&handle_dht_local_get_result_seen, NULL,
+ GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_RESULTS_KNOWN, 0},
{NULL, NULL, 0, 0}
};
-
+ forward_map = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
+ retry_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
GNUNET_SERVER_add_handlers (server, plugin_handlers);
GNUNET_SERVER_disconnect_notify (server, &handle_client_disconnect, NULL);
}
+
/**
- * SUPU: Call made from gnunet-service-dht.c
* Shutdown client subsystem.
*/
void
GDS_CLIENTS_done ()
{
-
-}
\ No newline at end of file
+ GNUNET_assert (client_head == NULL);
+ GNUNET_assert (client_tail == NULL);
+ if (GNUNET_SCHEDULER_NO_TASK != retry_task)
+ {
+ GNUNET_SCHEDULER_cancel (retry_task);
+ retry_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ if (NULL != retry_heap)
+ {
+ GNUNET_assert (0 == GNUNET_CONTAINER_heap_get_size (retry_heap));
+ GNUNET_CONTAINER_heap_destroy (retry_heap);
+ retry_heap = NULL;
+ }
+ if (NULL != forward_map)
+ {
+ GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (forward_map));
+ GNUNET_CONTAINER_multihashmap_destroy (forward_map);
+ forward_map = NULL;
+ }
+}
+
+/* end of gnunet-service-dht_clients.c */