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
* @brief library to access the DHT service
* @author Christian Grothoff
* @author Nathan Evans
- *
- * TODO: Only allow a single message until confirmed as received by
- * the service. For put messages call continuation as soon as
- * receipt acknowledged (then remove), for GET or other messages
- * only call continuation when data received.
- * Add unique identifier to message types requesting data to be
- * returned.
*/
+
#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 DEFAULT_DHT_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
+#define DEBUG_DHT_API GNUNET_NO
+/**
+ * Entry in our list of messages to be (re-)transmitted.
+ */
struct PendingMessage
{
/**
- * Message that is pending
+ * This is a doubly-linked list.
*/
- struct GNUNET_MessageHeader *msg;
+ struct PendingMessage *prev;
/**
- * Timeout for this message
+ * This is a doubly-linked list.
*/
- struct GNUNET_TIME_Relative timeout;
+ struct PendingMessage *next;
/**
- * Continuation to call on message send
- * or message receipt confirmation
+ * Message that is pending, allocated at the end
+ * of this struct.
+ */
+ 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;
/**
- * Continuation closure
+ * Closure for 'cont'.
*/
void *cont_cls;
/**
- * Whether or not to await verification the message
- * was received by the service
+ * Timeout task for this message
*/
- size_t is_unique;
+ GNUNET_SCHEDULER_TaskIdentifier timeout_task;
/**
* Unique ID for this request
*/
uint64_t unique_id;
-};
-
-struct GNUNET_DHT_GetContext
-{
-
-
/**
- * Iterator to call on data receipt
+ * 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.
*/
- GNUNET_DHT_GetIterator iter;
+ int free_on_send;
/**
- * Closure for the iterator callback
+ * GNUNET_YES if this message is in our pending queue right now.
*/
- void *iter_cls;
+ int in_pending_queue;
};
+
/**
- * Handle to control a unique operation (one that is
- * expected to return results)
+ * Handle to a route request
*/
struct GNUNET_DHT_RouteHandle
{
- /**
- * Unique identifier for this request (for key collisions)
- */
- uint64_t uid;
-
- /**
- * Key that this get request is for
- */
- GNUNET_HashCode key;
-
/**
* Iterator to call on data receipt
*/
* Main handle to this DHT api
*/
struct GNUNET_DHT_Handle *dht_handle;
-};
-/**
- * Handle for a non unique request, holds callback
- * which needs to be called before we allow other
- * messages to be processed and sent to the DHT service
- */
-struct GNUNET_DHT_NonUniqueHandle
-{
/**
- * Key that this get request is for
+ * The actual message sent for this request,
+ * used for retransmitting requests on service
+ * failure/reconnect. Freed on route_stop.
*/
- GNUNET_HashCode key;
+ struct PendingMessage *message;
/**
- * Type of data get request was for
+ * Key that this get request is for
*/
- uint32_t type;
+ GNUNET_HashCode key;
/**
- * Continuation to call on service
- * confirmation of message receipt.
+ * Unique identifier for this request (for key collisions). FIXME: redundant!?
*/
- GNUNET_SCHEDULER_Task cont;
+ uint64_t uid;
- /**
- * Send continuation cls
- */
- void *cont_cls;
};
struct GNUNET_CLIENT_Connection *client;
/**
- * Currently pending transmission request.
+ * Currently pending transmission request (or NULL).
*/
struct GNUNET_CLIENT_TransmitHandle *th;
/**
- * Message we are currently sending, only allow
- * a single message to be queued. If not unique
- * (typically a put request), await a confirmation
- * from the service that the message was received.
- * If unique, just fire and forget.
+ * Head of linked list of messages we would like to transmit.
*/
- struct PendingMessage *current;
+ struct PendingMessage *pending_head;
/**
- * Hash map containing the current outstanding unique requests
+ * Tail of linked list of messages we would like to transmit.
*/
- struct GNUNET_CONTAINER_MultiHashMap *outstanding_requests;
+ struct PendingMessage *pending_tail;
/**
- * Non unique handle. If set don't schedule another non
- * unique request.
+ * Hash map containing the current outstanding unique requests
+ * (values are of type 'struct GNUNET_DHT_RouteHandle').
*/
- struct GNUNET_DHT_NonUniqueHandle *non_unique_request;
+ struct GNUNET_CONTAINER_MultiHashMap *active_requests;
/**
- * Kill off the connection and any pending messages.
+ * Generator for unique ids.
*/
- 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);
-
-static GNUNET_HashCode * hash_from_uid(uint64_t uid)
-{
- int count;
- int remaining;
- GNUNET_HashCode *hash;
- hash = GNUNET_malloc(sizeof(GNUNET_HashCode));
- count = 0;
- while (count < sizeof(GNUNET_HashCode))
- {
- remaining = sizeof(GNUNET_HashCode) - count;
- if (remaining > sizeof(uid))
- remaining = sizeof(uid);
-
- memcpy(hash, &uid, remaining);
- count += remaining;
- }
+/**
+ * Transmit the next pending message, called by notify_transmit_ready
+ */
+static size_t
+transmit_pending (void *cls,
+ size_t size,
+ void *buf);
- return hash;
-}
/**
* 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)
-{
- struct GNUNET_DHT_Handle *handle = cls;
- struct GNUNET_DHT_Message *dht_msg;
- struct GNUNET_DHT_StopMessage *stop_msg;
- struct GNUNET_MessageHeader *enc_msg;
- struct GNUNET_DHT_RouteHandle *route_handle;
- uint64_t uid;
- GNUNET_HashCode *uid_hash;
- size_t enc_size;
- /* TODO: find out message type, handle callbacks for different types of messages.
- * Should be a non unique acknowledgment, or unique result. */
-
- if (msg == NULL)
- {
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Received NULL from server, connection down?\n", "DHT API");
-#endif
- return;
- }
-
- if (ntohs(msg->type) == GNUNET_MESSAGE_TYPE_DHT)
- {
- dht_msg = (struct GNUNET_DHT_Message *)msg;
- uid = GNUNET_ntohll(dht_msg->unique_id);
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Received response to message (uid %llu)\n", "DHT API", uid);
-#endif
- if (ntohs(dht_msg->unique))
- {
- uid_hash = hash_from_uid(ntohl(dht_msg->unique_id));
- route_handle = GNUNET_CONTAINER_multihashmap_get(handle->outstanding_requests, uid_hash);
- GNUNET_free(uid_hash);
- if (route_handle == NULL) /* We have no recollection of this request */
- {
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Received response to message (uid %llu), but have no recollection of it!\n", "DHT API", ntohl(dht_msg->unique_id));
-#endif
- }
- else
- {
- enc_size = ntohs(dht_msg->header.size) - sizeof(struct GNUNET_DHT_Message);
- GNUNET_assert(enc_size > 0);
- enc_msg = (struct GNUNET_MessageHeader *)&dht_msg[1];
- route_handle->iter(route_handle->iter_cls, enc_msg);
- }
- }
- }
- else if (ntohs(msg->type) == GNUNET_MESSAGE_TYPE_DHT_STOP)
- {
- stop_msg = (struct GNUNET_DHT_StopMessage *)msg;
- uid = GNUNET_ntohll(stop_msg->unique_id);
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Received response to message (uid %llu), current uid %llu\n", "DHT API", uid, handle->current->unique_id);
-#endif
- if (handle->current->unique_id == uid)
- {
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Have pending confirmation for this message!\n", "DHT API", uid);
-#endif
- if (handle->current->cont != NULL)
- GNUNET_SCHEDULER_add_continuation(handle->sched, handle->current->cont, handle->current->cont_cls, GNUNET_SCHEDULER_REASON_PREREQ_DONE);
-
- GNUNET_free(handle->current->msg);
- GNUNET_free(handle->current);
- handle->current = NULL;
- }
- }
- else
- {
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Received unknown message type %d\n", "DHT API", ntohs(msg->type));
-#endif
- }
+static void
+service_message_handler (void *cls,
+ const struct GNUNET_MessageHeader *msg);
- GNUNET_CLIENT_receive (handle->client,
- &service_message_handler,
- handle, GNUNET_TIME_UNIT_FOREVER_REL);
-}
/**
- * Initialize the connection with the DHT service.
- *
- * @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
+ * Try to (re)connect to the DHT service.
*
- * @return handle to the DHT service, or 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,
- unsigned int ht_len)
+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->current = NULL;
- handle->do_destroy = GNUNET_NO;
- handle->th = NULL;
-
- handle->client = GNUNET_CLIENT_connect(sched, "dht", cfg);
- handle->outstanding_requests = GNUNET_CONTAINER_multihashmap_create(ht_len);
-
+ if (handle->client != NULL)
+ return GNUNET_OK;
+ handle->client = GNUNET_CLIENT_connect (handle->sched, "dht", handle->cfg);
if (handle->client == NULL)
- {
- GNUNET_free(handle);
- return NULL;
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Failed to connect to the DHT service!\n"));
+ return GNUNET_NO;
}
-#if DEBUG_DHT_API
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 handle handle of the DHT connection to stop
+ * @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)
{
-#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;
+}
- 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);
+
}
/**
- * Send complete (or failed), schedule next (or don't)
+ * Try to send messages from list of messages to send
*/
static void
-finish (struct GNUNET_DHT_Handle *handle, int code)
+process_pending_messages (struct GNUNET_DHT_Handle *handle)
{
- /* TODO: if code is not GNUNET_OK, do something! */
- struct PendingMessage *pos = handle->current;
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Finish called!\n", "DHT API");
-#endif
- GNUNET_assert(pos != NULL);
+ struct PendingMessage *head;
- if (pos->is_unique)
+ 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)
{
- if (pos->cont != NULL)
- {
- if (code == GNUNET_SYSERR)
- GNUNET_SCHEDULER_add_continuation(handle->sched, pos->cont, pos->cont_cls, GNUNET_SCHEDULER_REASON_TIMEOUT);
- else
- GNUNET_SCHEDULER_add_continuation(handle->sched, pos->cont, pos->cont_cls, GNUNET_SCHEDULER_REASON_PREREQ_DONE);
- }
-
- GNUNET_free(pos->msg);
- handle->current = NULL;
- GNUNET_free(pos);
+ reconnect (handle);
+ return;
}
- /* Otherwise we need to wait for a response to this message! */
}
+
/**
* Transmit the next pending message, called by notify_transmit_ready
*/
static size_t
-transmit_pending (void *cls, size_t size, void *buf)
+transmit_pending (void *cls,
+ size_t size,
+ void *buf)
{
struct GNUNET_DHT_Handle *handle = cls;
+ struct PendingMessage *head;
size_t tsize;
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': In transmit_pending\n", "DHT API");
-#endif
+ handle->th = NULL;
if (buf == 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);
+ reconnect (handle);
return 0;
}
-
- handle->th = NULL;
-
- if (handle->current != NULL)
- {
- tsize = ntohs(handle->current->msg->size);
- if (size >= tsize)
+ if (NULL == (head = handle->pending_head))
+ return 0;
+
+ tsize = ntohs (head->msg->size);
+ if (size < tsize)
{
-#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);
- finish(handle, GNUNET_OK);
- return tsize;
+ process_pending_messages (handle);
+ return 0;
}
- else
+ memcpy (buf, head->msg, tsize);
+ GNUNET_CONTAINER_DLL_remove (handle->pending_head,
+ handle->pending_tail,
+ head);
+ if (head->timeout_task != GNUNET_SCHEDULER_NO_TASK)
{
- return 0;
+ GNUNET_SCHEDULER_cancel (handle->sched,
+ head->timeout_task);
+ head->timeout_task = GNUNET_SCHEDULER_NO_TASK;
}
- }
- /* Have no pending request */
- return 0;
+ 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;
}
+
+
/**
- * Try to (re)connect to the dht service.
- *
- * @return GNUNET_YES on success, GNUNET_NO on failure.
+ * Process a given reply that might match the given
+ * request.
*/
static int
-try_connect (struct GNUNET_DHT_Handle *handle)
+process_reply (void *cls,
+ const GNUNET_HashCode *key,
+ void *value)
{
- if (handle->client != NULL)
- return GNUNET_OK;
- handle->client = GNUNET_CLIENT_connect (handle->sched, "dht", handle->cfg);
- if (handle->client != NULL)
- return GNUNET_YES;
-#if DEBUG_STATISTICS
+ 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,
- _("Failed to connect to the dht service!\n"));
-#endif
- return GNUNET_NO;
+ "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;
}
/**
- * Try to send messages from list of messages to send
+ * 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 void process_pending_message(struct GNUNET_DHT_Handle *handle)
+static void
+service_message_handler (void *cls,
+ const struct GNUNET_MessageHeader *msg)
{
+ struct GNUNET_DHT_Handle *handle = cls;
+ const struct GNUNET_DHT_RouteResultMessage *dht_msg;
- if (handle->current == NULL)
- return; /* action already pending */
- if (GNUNET_YES != try_connect (handle))
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "%s called\n",
+ __FUNCTION__);
+ if (msg == NULL)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Error receiving data from DHT service, reconnecting\n");
+ reconnect (handle);
+ return;
+ }
+ if (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE_RESULT)
+ {
+ GNUNET_break (0);
+ reconnect (handle);
+ return;
+ }
+ if (ntohs (msg->size) < sizeof (struct GNUNET_DHT_RouteResultMessage))
{
- finish (handle, GNUNET_SYSERR);
+ 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);
+
+}
+
+
+/**
+ * Initialize the connection with the DHT service.
+ *
+ * @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
+ */
+struct GNUNET_DHT_Handle *
+GNUNET_DHT_connect (struct GNUNET_SCHEDULER_Handle *sched,
+ const struct GNUNET_CONFIGURATION_Handle *cfg,
+ unsigned int ht_len)
+{
+ struct GNUNET_DHT_Handle *handle;
- /* TODO: set do_destroy somewhere's, see what needs to happen in that case! */
- if (handle->do_destroy)
+ 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); /* FIXME: replace with proper disconnect stuffs */
+ GNUNET_DHT_disconnect (handle);
+ return NULL;
}
+ return handle;
+}
- if (NULL ==
- (handle->th = GNUNET_CLIENT_notify_transmit_ready (handle->client,
- ntohs(handle->current->msg->size),
- handle->current->timeout,
- GNUNET_YES,
- &transmit_pending, handle)))
+/**
+ * Shutdown connection with the DHT service.
+ *
+ * @param handle handle of the DHT connection to stop
+ */
+void
+GNUNET_DHT_disconnect (struct GNUNET_DHT_Handle *handle)
+{
+ struct PendingMessage *pm;
+
+ GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size(handle->active_requests));
+ if (handle->th != NULL)
{
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Failed to transmit request to dht service.\n");
-#endif
- finish (handle, GNUNET_SYSERR);
+ GNUNET_CLIENT_notify_transmit_ready_cancel (handle->th);
+ handle->th = NULL;
}
-#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
+ while (NULL != (pm = handle->pending_head))
+ {
+ 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 ***** */
+
+
/**
- * Iterator called on each result obtained from a generic route
- * operation
+ * Timeout for the transmission of a fire&forget-request. Clean it up.
+ *
+ * @param cls the 'struct PendingMessage'
+ * @param tc scheduler context
*/
-void get_reply_iterator (void *cls,
- const struct GNUNET_MessageHeader *reply)
+static void
+timeout_route_request (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
{
+ struct PendingMessage *pending = cls;
+ struct GNUNET_DHT_Handle *handle;
+ if (pending->free_on_send != GNUNET_YES)
+ {
+ /* timeouts should only apply to fire & forget requests! */
+ GNUNET_break (0);
+ return;
+ }
+ 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);
}
+
/**
- * Perform an asynchronous FIND_PEER operation on the DHT.
+ * Initiate a generic DHT route operation.
*
* @param handle handle to the DHT service
* @param key the key to look up
* @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
- * @param cont continuation to call when done;
- * reason will be TIMEOUT on error,
- * reason will be PREREQ_DONE on success
+ * 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"
*/
struct GNUNET_DHT_RouteHandle *
GNUNET_DHT_route_start (struct GNUNET_DHT_Handle *handle,
const GNUNET_HashCode *key,
- unsigned int desired_replication_level,
+ 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)
+ GNUNET_SCHEDULER_Task cont,
+ void *cont_cls)
{
- struct GNUNET_DHT_RouteHandle *route_handle;
struct PendingMessage *pending;
- struct GNUNET_DHT_Message *message;
- size_t is_unique;
- size_t msize;
- GNUNET_HashCode *uid_key;
- uint64_t uid;
-
- is_unique = GNUNET_YES;
- if (iter == NULL)
- is_unique = GNUNET_NO;
-
- route_handle = NULL;
- uid_key = NULL;
-
- do
- {
- GNUNET_free_non_null(uid_key);
- uid = GNUNET_CRYPTO_random_u64(GNUNET_CRYPTO_QUALITY_WEAK, -1);
- uid_key = hash_from_uid(uid);
- } while (GNUNET_CONTAINER_multihashmap_contains(handle->outstanding_requests, uid_key) == GNUNET_YES);
+ struct GNUNET_DHT_RouteMessage *message;
+ struct GNUNET_DHT_RouteHandle *route_handle;
+ uint16_t msize;
+ uint16_t esize;
- if (is_unique)
+ esize = ntohs (enc->size);
+ if (sizeof (struct GNUNET_DHT_RouteMessage) + esize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
- route_handle = GNUNET_malloc(sizeof(struct GNUNET_DHT_RouteHandle));
- memcpy(&route_handle->key, key, sizeof(GNUNET_HashCode));
+ 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 = uid;
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Unique ID is %llu\n", "DHT API", uid);
-#endif
- /**
- * Store based on random identifier!
- */
- GNUNET_CONTAINER_multihashmap_put(handle->outstanding_requests, uid_key, route_handle, GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
- msize = sizeof(struct GNUNET_DHT_Message) + ntohs(enc->size);
-
+ 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
{
- msize = sizeof(struct GNUNET_DHT_Message) + ntohs(enc->size);
+ route_handle = NULL;
+ pending->free_on_send = GNUNET_YES;
+ pending->timeout_task = GNUNET_SCHEDULER_add_delayed (handle->sched,
+ timeout,
+ &timeout_route_request,
+ pending);
}
-
- GNUNET_free(uid_key);
- message = GNUNET_malloc(msize);
- message->header.size = htons(msize);
- message->header.type = htons(GNUNET_MESSAGE_TYPE_DHT);
- memcpy(&message->key, key, sizeof(GNUNET_HashCode));
- message->options = htons(options);
- message->desired_replication_level = htons(options);
- message->unique = htons(is_unique);
- message->unique_id = GNUNET_htonll(uid);
- memcpy(&message[1], enc, ntohs(enc->size));
-
- pending = GNUNET_malloc(sizeof(struct PendingMessage));
- pending->msg = &message->header;
- pending->timeout = timeout;
- pending->cont = cont;
- pending->cont_cls = cont_cls;
- pending->is_unique = is_unique;
- pending->unique_id = uid;
-
- GNUNET_assert(handle->current == NULL);
-
- handle->current = 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;
}
-void
-GNUNET_DHT_route_stop (struct GNUNET_DHT_RouteHandle *fph);
-
/**
- * Perform an asynchronous GET operation on the DHT identified.
+ * Stop a previously issued routing request
*
- * @param handle handle to the DHT service
- * @param timeout how long to wait for transmission of this request to the 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
- * @param cont continuation to call once message sent
- * @param cont_cls closure for continuation
- *
- * @return handle to stop the async get
+ * @param route_handle handle to the request to stop
*/
-struct GNUNET_DHT_RouteHandle *
-GNUNET_DHT_get_start (struct GNUNET_DHT_Handle *handle,
- struct GNUNET_TIME_Relative timeout,
- uint32_t type,
- const GNUNET_HashCode * key,
- GNUNET_DHT_GetIterator iter,
- void *iter_cls,
- GNUNET_SCHEDULER_Task cont,
- void *cont_cls)
-{
- struct GNUNET_DHT_GetContext *get_context;
- struct GNUNET_DHT_GetMessage *get_msg;
-
- if (handle->current != NULL) /* Can't send right now, we have a pending message... */
- return NULL;
-
- get_context = GNUNET_malloc(sizeof(struct GNUNET_DHT_GetContext));
- get_context->iter = iter;
- get_context->iter_cls = iter_cls;
-
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Inserting pending get request with key %s\n", "DHT API", GNUNET_h2s(key));
-#endif
-
- 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);
-
- return GNUNET_DHT_route_start(handle, key, 0, 0, &get_msg->header, timeout, &get_reply_iterator, get_context, cont, cont_cls);
-
-}
-
-
void
GNUNET_DHT_route_stop (struct GNUNET_DHT_RouteHandle *route_handle)
{
+ struct GNUNET_DHT_Handle *handle;
struct PendingMessage *pending;
struct GNUNET_DHT_StopMessage *message;
size_t msize;
- GNUNET_HashCode *uid_key;
-
- msize = sizeof(struct GNUNET_DHT_StopMessage);
-
- message = GNUNET_malloc(msize);
- message->header.size = htons(msize);
- message->header.type = htons(GNUNET_MESSAGE_TYPE_DHT_STOP);
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Remove outstanding request for uid %llu\n", "DHT API", route_handle->uid);
-#endif
- message->unique_id = GNUNET_htonll(route_handle->uid);
- GNUNET_assert(route_handle->dht_handle->current == 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
+ {
+ /* 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");
+}
- pending = GNUNET_malloc(sizeof(struct PendingMessage));
- pending->msg = (struct GNUNET_MessageHeader *)message;
- pending->timeout = DEFAULT_DHT_TIMEOUT;
- pending->cont = NULL;
- pending->cont_cls = NULL;
- pending->is_unique = GNUNET_NO;
- pending->unique_id = route_handle->uid;
- GNUNET_assert(route_handle->dht_handle->current == NULL);
- route_handle->dht_handle->current = pending;
+/* ***** Special API for controlling DHT routing maintenance ******* */
- process_pending_message(route_handle->dht_handle);
- uid_key = hash_from_uid(route_handle->uid);
+/**
+ * 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;
- if (GNUNET_CONTAINER_multihashmap_remove(route_handle->dht_handle->outstanding_requests, uid_key, route_handle) != GNUNET_YES)
- {
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Remove outstanding request from hashmap failed for key %s, uid %llu\n", "DHT API", GNUNET_h2s(uid_key), route_handle->uid);
-#endif
- }
- GNUNET_free(uid_key);
- return;
+ 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.
+ * 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 get_handle handle to the 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_RouteHandle *get_handle)
+GNUNET_DHT_find_peers (struct GNUNET_DHT_Handle *handle,
+ GNUNET_SCHEDULER_Task cont,
+ void *cont_cls)
{
-#if OLDREMOVE
- struct GNUNET_DHT_GetMessage *get_msg;
- struct GNUNET_DHT_Handle *handle;
- GNUNET_HashCode *uid_key;
-#endif
-
- GNUNET_DHT_route_stop(get_handle);
+ send_control_message (handle,
+ GNUNET_MESSAGE_TYPE_DHT_FIND_PEER, 0,
+ cont, cont_cls);
+}
-#if OLDREMOVE
- uid_key = hash_from_uid(get_handle->uid);
- GNUNET_assert(GNUNET_CONTAINER_multihashmap_remove(handle->outstanding_requests, uid_key, get_handle) == GNUNET_YES);
- 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));
+#if HAVE_MALICIOUS
+/**
+ * Send a message to the DHT telling it to start issuing random GET
+ * requests every 'frequency' milliseconds.
+ *
+ * @param handle handle to the DHT service
+ * @param frequency delay between sending malicious messages
+ */
+void
+GNUNET_DHT_set_malicious_getter (struct GNUNET_DHT_Handle *handle,
+ struct GNUNET_TIME_Relative frequency)
+{
+ if (frequency.value > UINT16_MAX)
+ {
+ GNUNET_break (0);
+ return;
}
-#endif
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Removing pending get request with key %s, uid %llu\n", "DHT API", GNUNET_h2s(&get_handle->key), get_handle->uid);
-#endif
+ send_control_message (handle,
+ GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_GET, frequency.value,
+ NULL, NULL);
}
-
/**
- * Perform a PUT operation storing data in the DHT.
+ * Send a message to the DHT telling it to start issuing random PUT
+ * 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
*/
-void
-GNUNET_DHT_put (struct GNUNET_DHT_Handle *handle,
- const GNUNET_HashCode * key,
- uint32_t type,
- uint32_t size,
- const char *data,
- struct GNUNET_TIME_Absolute exp,
- struct GNUNET_TIME_Relative timeout,
- GNUNET_SCHEDULER_Task cont,
- void *cont_cls)
+void
+GNUNET_DHT_set_malicious_putter (struct GNUNET_DHT_Handle *handle,
+ struct GNUNET_TIME_Relative frequency)
{
- struct GNUNET_DHT_PutMessage *put_msg;
- size_t msize;
-
- if (handle->current != NULL)
+ if (frequency.value > UINT16_MAX)
{
- GNUNET_SCHEDULER_add_continuation(handle->sched, cont, cont_cls, GNUNET_SCHEDULER_REASON_TIMEOUT);
+ GNUNET_break (0);
return;
}
+ send_control_message (handle,
+ GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_PUT, frequency.value,
+ NULL, NULL);
+}
-#if DEBUG_DHT_API
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "`%s': Inserting pending put request with key %s\n", "DHT API", GNUNET_h2s(key));
-#endif
- 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);
- put_msg->data_size = htons(size);
- put_msg->expiration = exp;
- 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);
+}
- GNUNET_DHT_route_start(handle, key, 0, 0, &put_msg->header, timeout, NULL, NULL, cont, cont_cls);
+#endif
- GNUNET_free(put_msg);
-}
+/* end of dht_api.c */
projects / oweals / gnunet.git / blobdiff