GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
- by the Free Software Foundation; either version 2, or (at your
+ by the Free Software Foundation; either version 3, or (at your
option) any later version.
GNUnet is distributed in the hope that it will be useful, but
* @author Christian Grothoff
* @author Nathan Evans
*/
+
#include "platform.h"
#include "gnunet_bandwidth_lib.h"
#include "gnunet_client_lib.h"
#include "gnunet_dht_service.h"
#include "dht.h"
-#define DEBUG_DHT_API GNUNET_YES
+#define DEBUG_DHT_API GNUNET_NO
-struct PendingMessages
+/**
+ * Entry in our list of messages to be (re-)transmitted.
+ */
+struct PendingMessage
{
/**
- * Linked list of pending messages
+ * This is a doubly-linked list.
*/
- struct PendingMessages *next;
+ struct PendingMessage *prev;
/**
- * Message that is pending
+ * This is a doubly-linked list.
*/
- struct GNUNET_MessageHeader *msg;
+ struct PendingMessage *next;
/**
- * Timeout for this message
+ * Message that is pending, allocated at the end
+ * of this struct.
*/
- struct GNUNET_TIME_Relative timeout;
+ const struct GNUNET_MessageHeader *msg;
+
+ /**
+ * Handle to the DHT API context.
+ */
+ struct GNUNET_DHT_Handle *handle;
+
+ /**
+ * Continuation to call when the request has been
+ * transmitted (for the first time) to the service; can be NULL.
+ */
+ GNUNET_SCHEDULER_Task cont;
+
+ /**
+ * Closure for 'cont'.
+ */
+ void *cont_cls;
+
+ /**
+ * Timeout task for this message
+ */
+ GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+
+ /**
+ * Unique ID for this request
+ */
+ uint64_t unique_id;
+
+ /**
+ * Free the saved message once sent, set to GNUNET_YES for messages
+ * that do not receive responses; GNUNET_NO if this pending message
+ * is aliased from a 'struct GNUNET_DHT_RouteHandle' and will be freed
+ * from there.
+ */
+ int free_on_send;
+
+ /**
+ * GNUNET_YES if this message is in our pending queue right now.
+ */
+ int in_pending_queue;
};
+
+/**
+ * Handle to a route request
+ */
+struct GNUNET_DHT_RouteHandle
+{
+
+ /**
+ * Iterator to call on data receipt
+ */
+ GNUNET_DHT_ReplyProcessor iter;
+
+ /**
+ * Closure for the iterator callback
+ */
+ void *iter_cls;
+
+ /**
+ * Main handle to this DHT api
+ */
+ struct GNUNET_DHT_Handle *dht_handle;
+
+ /**
+ * The actual message sent for this request,
+ * used for retransmitting requests on service
+ * failure/reconnect. Freed on route_stop.
+ */
+ struct PendingMessage *message;
+
+ /**
+ * Key that this get request is for
+ */
+ GNUNET_HashCode key;
+
+ /**
+ * Unique identifier for this request (for key collisions). FIXME: redundant!?
+ */
+ uint64_t uid;
+
+};
+
+
/**
* Connection to the DHT service.
*/
struct GNUNET_CLIENT_Connection *client;
/**
- * Currently pending transmission request.
+ * Currently pending transmission request (or NULL).
*/
struct GNUNET_CLIENT_TransmitHandle *th;
/**
- * List of the currently pending messages for the DHT service.
+ * Head of linked list of messages we would like to transmit.
*/
- struct PendingMessages *pending_list;
+ struct PendingMessage *pending_head;
/**
- * Message we are currently sending.
+ * Tail of linked list of messages we would like to transmit.
*/
- struct PendingMessages *current;
+ struct PendingMessage *pending_tail;
/**
- * Hash map containing the current outstanding get requests
+ * Hash map containing the current outstanding unique requests
+ * (values are of type 'struct GNUNET_DHT_RouteHandle').
*/
- struct GNUNET_CONTAINER_MultiHashMap *outstanding_get_requests;
+ struct GNUNET_CONTAINER_MultiHashMap *active_requests;
/**
- * Hash map containing the current outstanding put requests, awaiting
- * a response
+ * Generator for unique ids.
*/
- struct GNUNET_CONTAINER_MultiHashMap *outstanding_put_requests;
-
- /**
- * Kill off the connection and any pending messages.
- */
- int do_destroy;
+ uint64_t uid_gen;
};
-static struct GNUNET_TIME_Relative default_request_timeout;
-/* Forward declaration */
-static void process_pending_message(struct GNUNET_DHT_Handle *handle);
+/**
+ * Transmit the next pending message, called by notify_transmit_ready
+ */
+static size_t
+transmit_pending (void *cls,
+ size_t size,
+ void *buf);
+
/**
* Handler for messages received from the DHT service
* a demultiplexer which handles numerous message types
*
*/
-void service_message_handler (void *cls,
- const struct GNUNET_MessageHeader *msg)
-{
+static void
+service_message_handler (void *cls,
+ const struct GNUNET_MessageHeader *msg);
+
- /* TODO: find out message type, handle callbacks for different types of messages.
- * Should be a put acknowledgment, get data or find node result. */
-}
/**
- * Initialize the connection with the DHT service.
+ * Try to (re)connect to the DHT service.
*
- * @param cfg configuration to use
- * @param sched scheduler to use
- * @return NULL on error
+ * @return GNUNET_YES on success, GNUNET_NO on failure.
*/
-struct GNUNET_DHT_Handle *
-GNUNET_DHT_connect (struct GNUNET_SCHEDULER_Handle *sched,
- const struct GNUNET_CONFIGURATION_Handle *cfg)
+static int
+try_connect (struct GNUNET_DHT_Handle *handle)
{
- struct GNUNET_DHT_Handle *handle;
-
- handle = GNUNET_malloc(sizeof(struct GNUNET_DHT_Handle));
-
- default_request_timeout = GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 5);
- handle->cfg = cfg;
- handle->sched = sched;
- handle->pending_list = NULL;
- handle->current = NULL;
- handle->do_destroy = GNUNET_NO;
- handle->th = NULL;
-
- handle->client = GNUNET_CLIENT_connect(sched, "dht", cfg);
- handle->outstanding_get_requests = GNUNET_CONTAINER_multihashmap_create(100); /* FIXME: better number */
- handle->outstanding_put_requests = GNUNET_CONTAINER_multihashmap_create(100); /* FIXME: better number */
+ if (handle->client != NULL)
+ return GNUNET_OK;
+ handle->client = GNUNET_CLIENT_connect (handle->sched, "dht", handle->cfg);
if (handle->client == NULL)
- return NULL;
-#if DEBUG_DHT_API
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Failed to connect to the DHT service!\n"));
+ return GNUNET_NO;
+ }
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Connection to service in progress\n", "DHT API");
-#endif
+ "Starting to process replies from DHT\n");
GNUNET_CLIENT_receive (handle->client,
&service_message_handler,
- handle, GNUNET_TIME_UNIT_FOREVER_REL);
-
- return handle;
+ handle,
+ GNUNET_TIME_UNIT_FOREVER_REL);
+ return GNUNET_YES;
}
/**
- * Shutdown connection with the DHT service.
+ * Add the request corresponding to the given route handle
+ * to the pending queue (if it is not already in there).
*
- * @param h connection to shut down
+ * @param cls the 'struct GNUNET_DHT_Handle*'
+ * @param key key for the request (not used)
+ * @param value the 'struct GNUNET_DHT_RouteHandle*'
+ * @return GNUNET_YES (always)
*/
-void
-GNUNET_DHT_disconnect (struct GNUNET_DHT_Handle *handle)
+static int
+add_request_to_pending (void *cls,
+ const GNUNET_HashCode *key,
+ void *value)
{
- struct PendingMessages *pos;
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Called GNUNET_DHT_disconnect\n", "DHT API");
-#endif
- GNUNET_assert(handle != NULL);
+ struct GNUNET_DHT_Handle *handle = cls;
+ struct GNUNET_DHT_RouteHandle *rh = value;
- if (handle->th != NULL) /* We have a live transmit request in the Aether */
+ if (GNUNET_NO == rh->message->in_pending_queue)
{
- GNUNET_CLIENT_notify_transmit_ready_cancel (handle->th);
- handle->th = NULL;
+ GNUNET_CONTAINER_DLL_insert (handle->pending_head,
+ handle->pending_tail,
+ rh->message);
+ rh->message->in_pending_queue = GNUNET_YES;
}
- if (handle->current != NULL) /* We are trying to send something now, clean it up */
- GNUNET_free(handle->current);
+ return GNUNET_YES;
+}
- while (NULL != (pos = handle->pending_list)) /* Remove all pending sends from the list */
- {
- handle->pending_list = pos->next;
- GNUNET_free(pos);
- }
- if (handle->client != NULL) /* Finally, disconnect from the service */
+
+/**
+ * Re-connect to the DHT, re-issue all pending requests if needed.
+ */
+static void
+reconnect (struct GNUNET_DHT_Handle *handle)
+{
+ if (handle->client != NULL)
{
- GNUNET_CLIENT_disconnect (handle->client, GNUNET_NO);
+ GNUNET_CLIENT_disconnect (handle->client,
+ GNUNET_NO);
handle->client = NULL;
}
-
- GNUNET_free (handle);
+ if (GNUNET_YES != try_connect (handle))
+ return;
+ GNUNET_CONTAINER_multihashmap_iterate (handle->active_requests,
+ &add_request_to_pending,
+ handle);
+ if (handle->pending_head == NULL)
+ return;
+ GNUNET_CLIENT_notify_transmit_ready (handle->client,
+ ntohs(handle->pending_head->msg->size),
+ GNUNET_TIME_UNIT_FOREVER_REL,
+ GNUNET_NO,
+ &transmit_pending,
+ handle);
+
}
/**
- * Handle to control a GET operation.
+ * Try to send messages from list of messages to send
*/
-struct GNUNET_DHT_GetHandle
+static void
+process_pending_messages (struct GNUNET_DHT_Handle *handle)
{
+ struct PendingMessage *head;
- /**
- * Key that this get request is for
- */
- GNUNET_HashCode key;
-
- /**
- * Type of data get request was for
- */
- uint32_t type;
-
- /**
- * Iterator to call on data receipt
- */
- GNUNET_DHT_Iterator iter;
+ if (GNUNET_YES != try_connect (handle))
+ return;
+ if (handle->th != NULL)
+ return;
+ if (NULL == (head = handle->pending_head))
+ return;
+ handle->th = GNUNET_CLIENT_notify_transmit_ready (handle->client,
+ ntohs (head->msg->size),
+ GNUNET_TIME_UNIT_FOREVER_REL,
+ GNUNET_YES,
+ &transmit_pending,
+ handle);
+ if (NULL == handle->th)
+ {
+ reconnect (handle);
+ return;
+ }
+}
- /**
- * Closure for the iterator callback
- */
- void *iter_cls;
-};
/**
- * Handle for a PUT request, holds callback
+ * Transmit the next pending message, called by notify_transmit_ready
*/
-struct GNUNET_DHT_PutHandle
+static size_t
+transmit_pending (void *cls,
+ size_t size,
+ void *buf)
{
- /**
- * Key that this get request is for
- */
- GNUNET_HashCode key;
+ struct GNUNET_DHT_Handle *handle = cls;
+ struct PendingMessage *head;
+ size_t tsize;
+
+ handle->th = NULL;
+ if (buf == NULL)
+ {
+ reconnect (handle);
+ return 0;
+ }
+ if (NULL == (head = handle->pending_head))
+ return 0;
+
+ tsize = ntohs (head->msg->size);
+ if (size < tsize)
+ {
+ process_pending_messages (handle);
+ return 0;
+ }
+ memcpy (buf, head->msg, tsize);
+ GNUNET_CONTAINER_DLL_remove (handle->pending_head,
+ handle->pending_tail,
+ head);
+ if (head->timeout_task != GNUNET_SCHEDULER_NO_TASK)
+ {
+ GNUNET_SCHEDULER_cancel (handle->sched,
+ head->timeout_task);
+ head->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ if (NULL != head->cont)
+ {
+ GNUNET_SCHEDULER_add_continuation (handle->sched,
+ head->cont,
+ head->cont_cls,
+ GNUNET_SCHEDULER_REASON_PREREQ_DONE);
+ head->cont = NULL;
+ head->cont_cls = NULL;
+ }
+ head->in_pending_queue = GNUNET_NO;
+ if (GNUNET_YES == head->free_on_send)
+ GNUNET_free (head);
+ process_pending_messages (handle);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Forwarded request of %u bytes to DHT service\n",
+ (unsigned int) tsize);
+ return tsize;
+}
- /**
- * Type of data get request was for
- */
- uint32_t type;
- /**
- * Continuation to call on put send
- */
- GNUNET_SCHEDULER_Task cont;
- /**
- * Send continuation cls
- */
- void *cont_cls;
-};
/**
- * Send complete (or failed), schedule next (or don't)
+ * Process a given reply that might match the given
+ * request.
*/
-static void
-finish (struct GNUNET_DHT_Handle *handle, int code)
+static int
+process_reply (void *cls,
+ const GNUNET_HashCode *key,
+ void *value)
{
- /* TODO: if code is not GNUNET_OK, do something! */
- struct PendingMessages *pos = handle->current;
- struct GNUNET_DHT_GetMessage *get;
- struct GNUNET_DHT_PutMessage *put;
-
- GNUNET_assert(pos != NULL);
-
- switch (ntohs(pos->msg->type))
- {
- case GNUNET_MESSAGE_TYPE_DHT_GET:
- get = (struct GNUNET_DHT_GetMessage *)pos->msg;
- GNUNET_free(get);
- break;
- case GNUNET_MESSAGE_TYPE_DHT_PUT:
- put = (struct GNUNET_DHT_PutMessage *)pos->msg;
- GNUNET_free(put);
- break;
- default:
- GNUNET_break(0);
- }
-
- handle->current = NULL;
-
- if (code != GNUNET_SYSERR)
- process_pending_message (handle);
-
- GNUNET_free(pos);
+ const struct GNUNET_DHT_RouteResultMessage *dht_msg = cls;
+ struct GNUNET_DHT_RouteHandle *rh = value;
+ const struct GNUNET_MessageHeader *enc_msg;
+ size_t enc_size;
+ uint64_t uid;
+ const struct GNUNET_PeerIdentity **get_path;
+ const struct GNUNET_PeerIdentity **put_path;
+ const struct GNUNET_PeerIdentity *pos;
+ uint16_t gpl;
+ uint16_t ppl;
+ unsigned int i;
+
+ uid = GNUNET_ntohll (dht_msg->unique_id);
+ if (uid != rh->uid)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Reply UID did not match request UID\n");
+ return GNUNET_YES;
+ }
+ enc_size = ntohs (dht_msg->header.size) - sizeof (struct GNUNET_DHT_RouteResultMessage);
+ if (enc_size < sizeof (struct GNUNET_MessageHeader))
+ {
+ GNUNET_break (0);
+ return GNUNET_NO;
+ }
+ pos = (const struct GNUNET_PeerIdentity *) &dht_msg[1];
+ ppl = ntohs (dht_msg->put_path_length);
+ gpl = ntohs (dht_msg->get_path_length);
+ if ( (ppl + gpl) * sizeof (struct GNUNET_PeerIdentity) > enc_size)
+ {
+ GNUNET_break (0);
+ return GNUNET_NO;
+ }
+ if (ppl > 0)
+ {
+ put_path = GNUNET_malloc ((ppl+1) * sizeof (struct GNUNET_PeerIdentity*));
+ for (i=0;i<ppl;i++)
+ {
+ put_path[i] = pos;
+ pos++;
+ }
+ put_path[ppl] = NULL;
+ }
+ else
+ put_path = NULL;
+ if (gpl > 0)
+ {
+ get_path = GNUNET_malloc ((gpl+1) * sizeof (struct GNUNET_PeerIdentity*));
+ for (i=0;i<gpl;i++)
+ {
+ get_path[i] = pos;
+ pos++;
+ }
+ get_path[gpl] = NULL;
+ }
+ else
+ get_path = NULL;
+ enc_size -= (ppl + gpl) * sizeof (struct GNUNET_PeerIdentity);
+ enc_msg = (const struct GNUNET_MessageHeader *) pos;
+ if (enc_size != ntohs (enc_msg->size))
+ {
+ GNUNET_break (0);
+ GNUNET_free_non_null (get_path);
+ GNUNET_free_non_null (put_path);
+ return GNUNET_NO;
+ }
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Processing reply.\n");
+ rh->iter (rh->iter_cls,
+ &rh->key,
+ get_path,
+ put_path,
+ enc_msg);
+ GNUNET_free_non_null (get_path);
+ GNUNET_free_non_null (put_path);
+ return GNUNET_YES;
}
+
/**
- * Transmit the next pending message, called by notify_transmit_ready
+ * Handler for messages received from the DHT service
+ * a demultiplexer which handles numerous message types
+ *
+ * @param cls the 'struct GNUNET_DHT_Handle'
+ * @param msg the incoming message
*/
-static size_t
-transmit_pending (void *cls, size_t size, void *buf)
+static void
+service_message_handler (void *cls,
+ const struct GNUNET_MessageHeader *msg)
{
struct GNUNET_DHT_Handle *handle = cls;
- size_t ret;
- size_t tsize;
+ const struct GNUNET_DHT_RouteResultMessage *dht_msg;
- if (buf == NULL)
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "%s called\n",
+ __FUNCTION__);
+ if (msg == NULL)
{
-#if DEBUG_DHT_API
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': In transmit_pending buf is NULL\n", "DHT API");
-#endif
- /* FIXME: free associated resources or summat */
- finish(handle, GNUNET_SYSERR);
- return 0;
+ "Error receiving data from DHT service, reconnecting\n");
+ reconnect (handle);
+ return;
}
-
- handle->th = NULL;
- ret = 0;
-
- if (handle->current != NULL)
- {
- tsize = ntohs(handle->current->msg->size);
- if (size >= tsize)
+ if (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE_RESULT)
{
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Sending message size %d\n", "DHT API", tsize);
-#endif
- memcpy(buf, handle->current->msg, tsize);
+ GNUNET_break (0);
+ reconnect (handle);
+ return;
}
- else
+ if (ntohs (msg->size) < sizeof (struct GNUNET_DHT_RouteResultMessage))
{
- return ret;
+ GNUNET_break (0);
+ reconnect (handle);
+ return;
}
- }
+ dht_msg = (const struct GNUNET_DHT_RouteResultMessage *) msg;
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Comparing reply `%s' against %u pending requests.\n",
+ GNUNET_h2s (&dht_msg->key),
+ GNUNET_CONTAINER_multihashmap_size (handle->active_requests));
+ GNUNET_CONTAINER_multihashmap_get_multiple (handle->active_requests,
+ &dht_msg->key,
+ &process_reply,
+ (void*) dht_msg);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Continuing to process replies from DHT\n");
+ GNUNET_CLIENT_receive (handle->client,
+ &service_message_handler,
+ handle, GNUNET_TIME_UNIT_FOREVER_REL);
- return ret;
}
/**
- * Try to (re)connect to the dht service.
+ * Initialize the connection with the DHT service.
*
- * @return GNUNET_YES on success, GNUNET_NO on failure.
+ * @param sched scheduler to use
+ * @param cfg configuration to use
+ * @param ht_len size of the internal hash table to use for
+ * processing multiple GET/FIND requests in parallel
+ *
+ * @return handle to the DHT service, or NULL on error
*/
-static int
-try_connect (struct GNUNET_DHT_Handle *ret)
+struct GNUNET_DHT_Handle *
+GNUNET_DHT_connect (struct GNUNET_SCHEDULER_Handle *sched,
+ const struct GNUNET_CONFIGURATION_Handle *cfg,
+ unsigned int ht_len)
{
- if (ret->client != NULL)
- return GNUNET_OK;
- ret->client = GNUNET_CLIENT_connect (ret->sched, "dht", ret->cfg);
- if (ret->client != NULL)
- return GNUNET_YES;
-#if DEBUG_STATISTICS
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- _("Failed to connect to the dht service!\n"));
-#endif
- return GNUNET_NO;
+ struct GNUNET_DHT_Handle *handle;
+
+ handle = GNUNET_malloc (sizeof (struct GNUNET_DHT_Handle));
+ handle->cfg = cfg;
+ handle->sched = sched;
+ handle->uid_gen = GNUNET_CRYPTO_random_u64(GNUNET_CRYPTO_QUALITY_WEAK, UINT64_MAX);
+ handle->active_requests = GNUNET_CONTAINER_multihashmap_create (ht_len);
+ if (GNUNET_NO == try_connect (handle))
+ {
+ GNUNET_DHT_disconnect (handle);
+ return NULL;
+ }
+ return handle;
}
/**
- * Try to send messages from list of messages to send
+ * Shutdown connection with the DHT service.
+ *
+ * @param handle handle of the DHT connection to stop
*/
-static void process_pending_message(struct GNUNET_DHT_Handle *handle)
+void
+GNUNET_DHT_disconnect (struct GNUNET_DHT_Handle *handle)
{
+ struct PendingMessage *pm;
- if (handle->current != NULL)
- return; /* action already pending */
- if (GNUNET_YES != try_connect (handle))
+ GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size(handle->active_requests));
+ if (handle->th != NULL)
{
- finish (handle, GNUNET_SYSERR);
- return;
+ GNUNET_CLIENT_notify_transmit_ready_cancel (handle->th);
+ handle->th = NULL;
}
-
- /* TODO: set do_destroy somewhere's, see what needs to happen in that case! */
- if (handle->do_destroy)
+ while (NULL != (pm = handle->pending_head))
{
- //GNUNET_DHT_disconnect (handle); /* FIXME: replace with proper disconnect stuffs */
+ GNUNET_CONTAINER_DLL_remove (handle->pending_head,
+ handle->pending_tail,
+ pm);
+ GNUNET_assert (GNUNET_YES == pm->free_on_send);
+ if (GNUNET_SCHEDULER_NO_TASK != pm->timeout_task)
+ GNUNET_SCHEDULER_cancel (handle->sched,
+ pm->timeout_task);
+ if (NULL != pm->cont)
+ GNUNET_SCHEDULER_add_continuation (handle->sched,
+ pm->cont,
+ pm->cont_cls,
+ GNUNET_SCHEDULER_REASON_TIMEOUT);
+ pm->in_pending_queue = GNUNET_NO;
+ GNUNET_free (pm);
}
+ if (handle->client != NULL)
+ {
+ GNUNET_CLIENT_disconnect (handle->client, GNUNET_YES);
+ handle->client = NULL;
+ }
+ GNUNET_CONTAINER_multihashmap_destroy(handle->active_requests);
+ GNUNET_free (handle);
+}
+
+
+
+
+/* ***** Special low-level API providing generic routing abstraction ***** */
+
+
+/**
+ * Timeout for the transmission of a fire&forget-request. Clean it up.
+ *
+ * @param cls the 'struct PendingMessage'
+ * @param tc scheduler context
+ */
+static void
+timeout_route_request (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct PendingMessage *pending = cls;
+ struct GNUNET_DHT_Handle *handle;
- /* schedule next action */
- handle->current = handle->pending_list;
- if (NULL == handle->current)
+ if (pending->free_on_send != GNUNET_YES)
{
+ /* timeouts should only apply to fire & forget requests! */
+ GNUNET_break (0);
return;
}
- handle->pending_list = handle->pending_list->next;
- handle->current->next = NULL;
-
- if (NULL ==
- (handle->th = GNUNET_CLIENT_notify_transmit_ready (handle->client,
- ntohs(handle->current->msg->size),
- handle->current->timeout,
- GNUNET_YES,
- &transmit_pending, handle)))
- {
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Failed to transmit request to dht service.\n");
-#endif
- finish (handle, GNUNET_SYSERR);
- }
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Scheduled sending message of size %d to service\n", "DHT API", ntohs(handle->current->msg->size));
-#endif
+ handle = pending->handle;
+ GNUNET_CONTAINER_DLL_remove (handle->pending_head,
+ handle->pending_tail,
+ pending);
+ if (pending->cont != NULL)
+ pending->cont (pending->cont_cls,
+ tc);
+ GNUNET_free (pending);
}
+
/**
- * Add a pending message to the linked list of messages which need to be sent
+ * Initiate a generic DHT route operation.
*
- * @param handle handle to the specified DHT api
- * @param msg the message to add to the list
+ * @param handle handle to the DHT service
+ * @param key the key to look up
+ * @param desired_replication_level how many peers should ultimately receive
+ * this message (advisory only, target may be too high for the
+ * given DHT or not hit exactly).
+ * @param options options for routing
+ * @param enc send the encapsulated message to a peer close to the key
+ * @param iter function to call on each result, NULL if no replies are expected
+ * @param iter_cls closure for iter
+ * @param timeout when to abort with an error if we fail to get
+ * a confirmation for the request (when necessary) or how long
+ * to wait for tramission to the service; only applies
+ * if 'iter' is NULL
+ * @param cont continuation to call when the request has been transmitted
+ * the first time to the service
+ * @param cont_cls closure for cont
+ * @return handle to stop the request, NULL if the request is "fire and forget"
*/
-static void add_pending(struct GNUNET_DHT_Handle *handle, struct GNUNET_MessageHeader *msg)
+struct GNUNET_DHT_RouteHandle *
+GNUNET_DHT_route_start (struct GNUNET_DHT_Handle *handle,
+ const GNUNET_HashCode *key,
+ uint32_t desired_replication_level,
+ enum GNUNET_DHT_RouteOption options,
+ const struct GNUNET_MessageHeader *enc,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_DHT_ReplyProcessor iter,
+ void *iter_cls,
+ GNUNET_SCHEDULER_Task cont,
+ void *cont_cls)
{
- struct PendingMessages *new_message;
- struct PendingMessages *pos;
- struct PendingMessages *last;
-
- new_message = GNUNET_malloc(sizeof(struct PendingMessages));
- new_message->msg = msg;
- new_message->timeout = default_request_timeout;
-
- if (handle->pending_list != NULL)
+ struct PendingMessage *pending;
+ struct GNUNET_DHT_RouteMessage *message;
+ struct GNUNET_DHT_RouteHandle *route_handle;
+ uint16_t msize;
+ uint16_t esize;
+
+ esize = ntohs (enc->size);
+ if (sizeof (struct GNUNET_DHT_RouteMessage) + esize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
- pos = handle->pending_list;
- while(pos != NULL)
- {
- last = pos;
- pos = pos->next;
- }
- new_message->next = last->next; /* Should always be null */
- last->next = new_message;
+ GNUNET_break (0);
+ return NULL;
+ }
+ msize = sizeof (struct GNUNET_DHT_RouteMessage) + esize;
+ pending = GNUNET_malloc (sizeof (struct PendingMessage) + msize);
+ message = (struct GNUNET_DHT_RouteMessage*) &pending[1];
+ pending->msg = &message->header;
+ pending->handle = handle;
+ pending->cont = cont;
+ pending->cont_cls = cont_cls;
+
+ message->header.size = htons (msize);
+ message->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE);
+ message->key = *key;
+ message->options = htonl ((uint32_t) options);
+ message->desired_replication_level = htonl (desired_replication_level);
+ handle->uid_gen++;
+ message->unique_id = GNUNET_htonll (handle->uid_gen);
+ memcpy (&message[1], enc, esize);
+
+ if (iter != NULL)
+ {
+ route_handle = GNUNET_malloc (sizeof (struct GNUNET_DHT_RouteHandle));
+ route_handle->key = *key;
+ route_handle->iter = iter;
+ route_handle->iter_cls = iter_cls;
+ route_handle->dht_handle = handle;
+ route_handle->uid = handle->uid_gen;
+ route_handle->message = pending;
+ GNUNET_CONTAINER_multihashmap_put (handle->active_requests,
+ key,
+ route_handle,
+ GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
}
else
{
- new_message->next = handle->pending_list; /* Will always be null */
- handle->pending_list = new_message;
+ route_handle = NULL;
+ pending->free_on_send = GNUNET_YES;
+ pending->timeout_task = GNUNET_SCHEDULER_add_delayed (handle->sched,
+ timeout,
+ &timeout_route_request,
+ pending);
}
-
- process_pending_message(handle);
+ GNUNET_CONTAINER_DLL_insert (handle->pending_head,
+ handle->pending_tail,
+ pending);
+ pending->in_pending_queue = GNUNET_YES;
+ process_pending_messages (handle);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "DHT route start request processed, returning %p\n",
+ route_handle);
+ return route_handle;
}
+
/**
- * Perform an asynchronous GET operation on the DHT identified.
+ * Stop a previously issued routing request
*
- * @param h handle to the DHT service
- * @param type expected type of the response object
- * @param key the key to look up
- * @param iter function to call on each result
- * @param iter_cls closure for iter
- * @return handle to stop the async get
+ * @param route_handle handle to the request to stop
*/
-struct GNUNET_DHT_GetHandle *
-GNUNET_DHT_get_start (struct GNUNET_DHT_Handle *handle,
- uint32_t type,
- const GNUNET_HashCode * key,
- GNUNET_DHT_Iterator iter,
- void *iter_cls)
+void
+GNUNET_DHT_route_stop (struct GNUNET_DHT_RouteHandle *route_handle)
{
- struct GNUNET_DHT_GetMessage *get_msg;
- struct GNUNET_DHT_GetHandle *get_handle;
-
- get_handle = GNUNET_CONTAINER_multihashmap_get(handle->outstanding_get_requests, key);
+ struct GNUNET_DHT_Handle *handle;
+ struct PendingMessage *pending;
+ struct GNUNET_DHT_StopMessage *message;
+ size_t msize;
- if (get_handle != NULL)
+ handle = route_handle->dht_handle;
+ if (GNUNET_NO == route_handle->message->in_pending_queue)
+ {
+ /* need to send stop message */
+ msize = sizeof (struct GNUNET_DHT_StopMessage);
+ pending = GNUNET_malloc (sizeof (struct PendingMessage) +
+ msize);
+ message = (struct GNUNET_DHT_StopMessage*) &pending[1];
+ pending->msg = &message->header;
+ message->header.size = htons (msize);
+ message->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE_STOP);
+ message->unique_id = GNUNET_htonll (route_handle->uid);
+ message->key = route_handle->key;
+ pending->handle = handle;
+ pending->free_on_send = GNUNET_YES;
+ pending->in_pending_queue = GNUNET_YES;
+ GNUNET_CONTAINER_DLL_insert (handle->pending_head,
+ handle->pending_tail,
+ pending);
+ process_pending_messages (handle);
+ }
+ else
{
- /*
- * A get has been previously sent, return existing handle.
- * FIXME: should we re-transmit the request to the DHT service?
- */
- return get_handle;
+ /* simply remove pending request from message queue before
+ transmission, no need to transmit STOP request! */
+ GNUNET_CONTAINER_DLL_remove (handle->pending_head,
+ handle->pending_tail,
+ route_handle->message);
}
+ GNUNET_assert (GNUNET_YES ==
+ GNUNET_CONTAINER_multihashmap_remove (route_handle->dht_handle->active_requests,
+ &route_handle->key,
+ route_handle));
+ GNUNET_free(route_handle->message);
+ GNUNET_free(route_handle);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "DHT route stop request processed\n");
+}
- get_handle = GNUNET_malloc(sizeof(struct GNUNET_DHT_GetHandle));
- get_handle->type = type;
- memcpy(&get_handle->key, key, sizeof(GNUNET_HashCode));
- get_handle->iter = iter;
- get_handle->iter_cls = iter_cls;
- GNUNET_CONTAINER_multihashmap_put(handle->outstanding_get_requests, key, get_handle, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
- get_msg = GNUNET_malloc(sizeof(struct GNUNET_DHT_GetMessage));
- get_msg->header.type = htons(GNUNET_MESSAGE_TYPE_DHT_GET);
- get_msg->header.size = htons(sizeof(struct GNUNET_DHT_GetMessage));
- get_msg->type = htonl(type);
- memcpy(&get_msg->key, key, sizeof(GNUNET_HashCode));
+/* ***** Special API for controlling DHT routing maintenance ******* */
- add_pending(handle, &get_msg->header);
- return get_handle;
+/**
+ * Send a control message to the DHT.
+ *
+ * @param handle handle to the DHT service
+ * @param command command
+ * @param variable variable to the command
+ * @param cont continuation to call when done (transmitting request to service)
+ * @param cont_cls closure for cont
+ */
+static void
+send_control_message (struct GNUNET_DHT_Handle *handle,
+ uint16_t command,
+ uint16_t variable,
+ GNUNET_SCHEDULER_Task cont,
+ void *cont_cls)
+{
+ struct GNUNET_DHT_ControlMessage *msg;
+ struct PendingMessage *pending;
+
+ pending = GNUNET_malloc (sizeof (struct PendingMessage) +
+ sizeof(struct GNUNET_DHT_ControlMessage));
+ msg = (struct GNUNET_DHT_ControlMessage*) &pending[1];
+ pending->msg = &msg->header;
+ msg->header.size = htons (sizeof(struct GNUNET_DHT_ControlMessage));
+ msg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CONTROL);
+ msg->command = htons (command);
+ msg->variable = htons (variable);
+ pending->free_on_send = GNUNET_YES;
+ pending->cont = cont;
+ pending->cont_cls = cont_cls;
+ pending->in_pending_queue = GNUNET_YES;
+ GNUNET_CONTAINER_DLL_insert (handle->pending_head,
+ handle->pending_tail,
+ pending);
+ process_pending_messages (handle);
}
/**
- * Stop async DHT-get. Frees associated resources.
+ * Send a message to the DHT telling it to issue a single find
+ * peer request using the peers unique identifier as key. This
+ * is used to fill the routing table, and is normally controlled
+ * by the DHT itself. However, for testing and perhaps more
+ * close control over the DHT, this can be explicitly managed.
*
- * @param record GET operation to stop.
+ * @param handle handle to the DHT service
+ * @param cont continuation to call when done (transmitting request to service)
+ * @param cont_cls closure for cont
*/
void
-GNUNET_DHT_get_stop (struct GNUNET_DHT_Handle *handle, struct GNUNET_DHT_GetHandle *get_handle)
+GNUNET_DHT_find_peers (struct GNUNET_DHT_Handle *handle,
+ GNUNET_SCHEDULER_Task cont,
+ void *cont_cls)
{
- struct GNUNET_DHT_GetMessage *get_msg;
+ send_control_message (handle,
+ GNUNET_MESSAGE_TYPE_DHT_FIND_PEER, 0,
+ cont, cont_cls);
+}
- if (handle->do_destroy == GNUNET_NO)
- {
- get_msg = GNUNET_malloc(sizeof(struct GNUNET_DHT_GetMessage));
- get_msg->header.type = htons(GNUNET_MESSAGE_TYPE_DHT_GET_STOP);
- get_msg->header.size = htons(sizeof(struct GNUNET_DHT_GetMessage));
- get_msg->type = htonl(get_handle->type);
- memcpy(&get_msg->key, &get_handle->key, sizeof(GNUNET_HashCode));
- add_pending(handle, &get_msg->header);
- }
-
- GNUNET_assert(GNUNET_CONTAINER_multihashmap_remove(handle->outstanding_get_requests, &get_handle->key, get_handle) == GNUNET_YES);
- GNUNET_free(get_handle);
-}
+#if HAVE_MALICIOUS
/**
- * Perform a PUT operation storing data in the DHT.
+ * Send a message to the DHT telling it to start issuing random GET
+ * requests every 'frequency' milliseconds.
*
- * @param h handle to DHT service
- * @param key the key to store under
- * @param type type of the value
- * @param size number of bytes in data; must be less than 64k
- * @param data the data to store
- * @param exp desired expiration time for the value
- * @param cont continuation to call when done;
- * reason will be TIMEOUT on error,
- * reason will be PREREQ_DONE on success
- * @param cont_cls closure for cont
- *
- * @return GNUNET_YES if put message is queued for transmission
+ * @param handle handle to the DHT service
+ * @param frequency delay between sending malicious messages
*/
-int GNUNET_DHT_put (struct GNUNET_DHT_Handle *handle,
- const GNUNET_HashCode * key,
- uint32_t type,
- uint32_t size,
- const char *data,
- struct GNUNET_TIME_Relative exp,
- GNUNET_SCHEDULER_Task cont,
- void *cont_cls)
+void
+GNUNET_DHT_set_malicious_getter (struct GNUNET_DHT_Handle *handle,
+ struct GNUNET_TIME_Relative frequency)
{
- struct GNUNET_DHT_PutMessage *put_msg;
- struct GNUNET_DHT_PutHandle *put_handle;
- size_t msize;
-
- put_handle = GNUNET_CONTAINER_multihashmap_get(handle->outstanding_put_requests, key);
-
- if (put_handle != NULL)
+ if (frequency.value > UINT16_MAX)
{
- /*
- * A put has been previously queued, but not yet sent.
- * FIXME: change the continuation function and callback or something?
- */
- return GNUNET_NO;
+ GNUNET_break (0);
+ return;
}
+ send_control_message (handle,
+ GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_GET, frequency.value,
+ NULL, NULL);
+}
- put_handle = GNUNET_malloc(sizeof(struct GNUNET_DHT_PutHandle));
- put_handle->type = type;
- memcpy(&put_handle->key, key, sizeof(GNUNET_HashCode));
+/**
+ * Send a message to the DHT telling it to start issuing random PUT
+ * requests every 'frequency' milliseconds.
+ *
+ * @param handle handle to the DHT service
+ * @param frequency delay between sending malicious messages
+ */
+void
+GNUNET_DHT_set_malicious_putter (struct GNUNET_DHT_Handle *handle,
+ struct GNUNET_TIME_Relative frequency)
+{
+ if (frequency.value > UINT16_MAX)
+ {
+ GNUNET_break (0);
+ return;
+ }
+ send_control_message (handle,
+ GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_PUT, frequency.value,
+ NULL, NULL);
+}
- GNUNET_CONTAINER_multihashmap_put(handle->outstanding_put_requests, key, put_handle, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
- msize = sizeof(struct GNUNET_DHT_PutMessage) + size;
- put_msg = GNUNET_malloc(msize);
- put_msg->header.type = htons(GNUNET_MESSAGE_TYPE_DHT_PUT);
- put_msg->header.size = htons(msize);
- put_msg->type = htonl(type);
- memcpy(&put_msg->key, key, sizeof(GNUNET_HashCode));
- memcpy(&put_msg[1], data, size);
+/**
+ * Send a message to the DHT telling it to start dropping
+ * all requests received.
+ *
+ * @param handle handle to the DHT service
+ */
+void
+GNUNET_DHT_set_malicious_dropper (struct GNUNET_DHT_Handle *handle)
+{
+ send_control_message (handle,
+ GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_DROP, 0,
+ NULL, NULL);
+}
- add_pending(handle, &put_msg->header);
+#endif
- return GNUNET_YES;
-}
+/* end of dht_api.c */