/**
* @file dht/gnunet-service-xdht_routing.c
* @brief GNUnet DHT tracking of requests for routing replies
- * @author Christian Grothoff
+ * @author Supriti Singh
*/
#include "platform.h"
#include "gnunet-service-xdht_neighbours.h"
#include "gnunet-service-xdht_routing.h"
#include "gnunet-service-xdht.h"
+/* FIXME
+ * 1. We need field to understand which routing table is for which peer.
+ * 2. Better function names and variable names.
+ * 3. Use destination peer id as key for routing table.
+ * 4. What does GDS stands for?
+ *
+ */
+
/**
* Number of requests we track at most (for routing replies).
/**
- * Information we keep about all recent GET requests
- * so that we can route replies.
+ * Routing table entry .
*/
-struct RecentRequest
+struct RoutingTrail
{
-
- /**
- * The peer this request was received from.
- */
- struct GNUNET_PeerIdentity peer;
-
- /**
- * Key of this request.
- */
- struct GNUNET_HashCode key;
-
- /**
- * Position of this node in the min heap.
- */
- struct GNUNET_CONTAINER_HeapNode *heap_node;
-
- /**
- * Bloomfilter for replies to drop.
- */
- struct GNUNET_CONTAINER_BloomFilter *reply_bf;
-
/**
- * Type of the requested block.
+ * Source peer .
*/
- enum GNUNET_BLOCK_Type type;
+ struct GNUNET_PeerIdentity *source;
/**
- * extended query (see gnunet_block_lib.h). Allocated at the
- * end of this struct.
+ * Destination peer.
*/
- const void *xquery;
+ struct GNUNET_PeerIdentity *destination;
/**
- * Number of bytes in xquery.
- */
- size_t xquery_size;
-
- /**
- * Mutator value for the reply_bf, see gnunet_block_lib.h
+ * The peer this request was received from.
*/
- uint32_t reply_bf_mutator;
+ struct GNUNET_PeerIdentity *previous_hop;
/**
- * Request options.
+ * The peer to which this request should be passed to.
*/
- enum GNUNET_DHT_RouteOption options;
-
+ struct GNUNET_PeerIdentity *next_hop;
+
};
/**
- * Recent requests by time inserted.
+ * Routing table of the peer
*/
-static struct GNUNET_CONTAINER_Heap *recent_heap;
-
-/**
- * Recently seen requests by key.
- */
-static struct GNUNET_CONTAINER_MultiHashMap *recent_map;
+static struct GNUNET_CONTAINER_MultiPeerMap *routing_table;
/**
- * Closure for the 'process' function.
+ * FIXME: Change the name of variable.
+ * Ensure that everywhere in this file you are using destination as the key.
+ * Add a new entry to our routing table.
+ * @param source peer
+ * @param destintation
+ * @param prev_hop
+ * @param next_hop
*/
-struct ProcessContext
+void
+GDS_ROUTING_add (struct GNUNET_PeerIdentity *source,
+ struct GNUNET_PeerIdentity *dest,
+ struct GNUNET_PeerIdentity *prev_hop,
+ struct GNUNET_PeerIdentity *next_hop)
{
- /**
- * Path of the original PUT
- */
- const struct GNUNET_PeerIdentity *put_path;
-
- /**
- * Path of the reply.
- */
- const struct GNUNET_PeerIdentity *get_path;
-
- /**
- * Payload of the reply.
- */
- const void *data;
-
- /**
- * Expiration time of the result.
- */
- struct GNUNET_TIME_Absolute expiration_time;
-
- /**
- * Number of entries in 'put_path'.
- */
- unsigned int put_path_length;
-
- /**
- * Number of entries in 'get_path'.
- */
- unsigned int get_path_length;
-
- /**
- * Number of bytes in 'data'.
- */
- size_t data_size;
-
- /**
- * Type of the reply.
- */
- enum GNUNET_BLOCK_Type type;
-
-};
+ struct RoutingTrail *new_routing_entry;
+
+ new_routing_entry = GNUNET_malloc (sizeof (struct RoutingTrail));
+ new_routing_entry->source = source;
+ new_routing_entry->previous_hop = prev_hop;
+ new_routing_entry->next_hop = next_hop;
+ new_routing_entry->destination = dest;
+
+ GNUNET_assert (GNUNET_OK ==
+ GNUNET_CONTAINER_multipeermap_put (routing_table,
+ dest, new_routing_entry,
+ GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
+}
/**
- * Forward the result to the given peer if it matches the request.
- *
- * @param cls the `struct ProcessContext` with the result
- * @param key the query
- * @param value the `struct RecentRequest` with the request
- * @return #GNUNET_OK (continue to iterate),
- * #GNUNET_SYSERR if the result is malformed or type unsupported
+ * Find the next hop to send packet to .
+ * @return next hop peer id
*/
-static int
-process (void *cls, const struct GNUNET_HashCode * key, void *value)
+struct GNUNET_PeerIdentity *
+GDS_Routing_search(struct GNUNET_PeerIdentity *source_peer,
+ struct GNUNET_PeerIdentity *destination_peer,
+ struct GNUNET_PeerIdentity *prev_hop)
{
- struct ProcessContext *pc = cls;
- struct RecentRequest *rr = value;
- enum GNUNET_BLOCK_EvaluationResult eval;
- unsigned int gpl;
- unsigned int ppl;
- struct GNUNET_HashCode hc;
- const struct GNUNET_HashCode *eval_key;
-
- if ((rr->type != GNUNET_BLOCK_TYPE_ANY) && (rr->type != pc->type))
- return GNUNET_OK; /* type missmatch */
-
- if (0 != (rr->options & GNUNET_DHT_RO_RECORD_ROUTE))
- {
- gpl = pc->get_path_length;
- ppl = pc->put_path_length;
- }
- else
- {
- gpl = 0;
- ppl = 0;
- }
- if ((0 != (rr->options & GNUNET_DHT_RO_FIND_PEER)) &&
- (pc->type == GNUNET_BLOCK_TYPE_DHT_HELLO))
- {
- /* key may not match HELLO, which is OK since
- * the search is approximate. Still, the evaluation
- * would fail since the match is not exact. So
- * we fake it by changing the key to the actual PID ... */
- GNUNET_BLOCK_get_key (GDS_block_context, GNUNET_BLOCK_TYPE_DHT_HELLO,
- pc->data, pc->data_size, &hc);
- eval_key = &hc;
- }
- else
- {
- eval_key = key;
- }
- eval =
- GNUNET_BLOCK_evaluate (GDS_block_context, pc->type, eval_key,
- &rr->reply_bf, rr->reply_bf_mutator, rr->xquery,
- rr->xquery_size, pc->data, pc->data_size);
- switch (eval)
- {
- case GNUNET_BLOCK_EVALUATION_OK_MORE:
- case GNUNET_BLOCK_EVALUATION_OK_LAST:
- GNUNET_STATISTICS_update (GDS_stats,
- gettext_noop
- ("# Good REPLIES matched against routing table"),
- 1, GNUNET_NO);
- GDS_NEIGHBOURS_handle_reply (&rr->peer, pc->type, pc->expiration_time, key,
- ppl, pc->put_path, gpl, pc->get_path, pc->data,
- pc->data_size);
- break;
- case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
- GNUNET_STATISTICS_update (GDS_stats,
- gettext_noop
- ("# Duplicate REPLIES matched against routing table"),
- 1, GNUNET_NO);
- return GNUNET_OK;
- case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
- GNUNET_STATISTICS_update (GDS_stats,
- gettext_noop
- ("# Invalid REPLIES matched against routing table"),
- 1, GNUNET_NO);
- return GNUNET_SYSERR;
- case GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT:
- GNUNET_STATISTICS_update (GDS_stats,
- gettext_noop
- ("# Irrelevant REPLIES matched against routing table"),
- 1, GNUNET_NO);
- return GNUNET_OK;
- case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
- GNUNET_break (0);
- return GNUNET_OK;
- case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
- GNUNET_break (0);
- return GNUNET_OK;
- case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
- GNUNET_STATISTICS_update (GDS_stats,
- gettext_noop
- ("# Unsupported REPLIES matched against routing table"),
- 1, GNUNET_NO);
- return GNUNET_SYSERR;
- default:
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- return GNUNET_OK;
+ struct RoutingTrail *trail;
+ trail = (struct RoutingTrail *)(GNUNET_CONTAINER_multipeermap_get(routing_table,destination_peer));
+
+ if(trail == NULL)
+ return NULL;
+
+ return trail->next_hop;
}
-/**
+/**FIXME: Old implementation just to remove error
* Handle a reply (route to origin). Only forwards the reply back to
* other peers waiting for it. Does not do local caching or
* forwarding to local clients. Essentially calls
const struct GNUNET_PeerIdentity *get_path,
const void *data, size_t data_size)
{
- struct ProcessContext pc;
-
- pc.type = type;
- pc.expiration_time = expiration_time;
- pc.put_path_length = put_path_length;
- pc.put_path = put_path;
- pc.get_path_length = get_path_length;
- pc.get_path = get_path;
- pc.data = data;
- pc.data_size = data_size;
- if (NULL == data)
- {
- /* Some apps might have an 'empty' reply as a valid reply; however,
- 'process' will call GNUNET_BLOCK_evaluate' which treats a 'NULL'
- reply as request-validation (but we need response-validation).
- So we set 'data' to a 0-byte non-NULL value just to be sure */
- GNUNET_break (0 == data_size);
- pc.data_size = 0;
- pc.data = ""; /* something not null */
- }
- GNUNET_CONTAINER_multihashmap_get_multiple (recent_map, key, &process, &pc);
-}
-
-
-/**
- * Remove the oldest entry from the DHT routing table. Must only
- * be called if it is known that there is at least one entry
- * in the heap and hashmap.
- */
-static void
-expire_oldest_entry ()
-{
- struct RecentRequest *recent_req;
-
- GNUNET_STATISTICS_update (GDS_stats,
- gettext_noop
- ("# Entries removed from routing table"), 1,
- GNUNET_NO);
- recent_req = GNUNET_CONTAINER_heap_peek (recent_heap);
- GNUNET_assert (recent_req != NULL);
- GNUNET_CONTAINER_heap_remove_node (recent_req->heap_node);
- GNUNET_CONTAINER_bloomfilter_free (recent_req->reply_bf);
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multihashmap_remove (recent_map,
- &recent_req->key,
- recent_req));
- GNUNET_free (recent_req);
-}
-
-
-/**
- * Try to combine multiple recent requests for the same value
- * (if they come from the same peer).
- *
- * @param cls the new 'struct RecentRequest' (to discard upon successful combination)
- * @param key the query
- * @param value the existing 'struct RecentRequest' (to update upon successful combination)
- * @return GNUNET_OK (continue to iterate),
- * GNUNET_SYSERR if the request was successfully combined
- */
-static int
-try_combine_recent (void *cls, const struct GNUNET_HashCode * key, void *value)
-{
- struct RecentRequest *in = cls;
- struct RecentRequest *rr = value;
-
- if ( (0 != memcmp (&in->peer,
- &rr->peer,
- sizeof (struct GNUNET_PeerIdentity))) ||
- (in->type != rr->type) ||
- (in->xquery_size != rr->xquery_size) ||
- (0 != memcmp (in->xquery,
- rr->xquery,
- in->xquery_size)) )
- return GNUNET_OK;
- if (in->reply_bf_mutator != rr->reply_bf_mutator)
- {
- rr->reply_bf_mutator = in->reply_bf_mutator;
- GNUNET_CONTAINER_bloomfilter_free (rr->reply_bf);
- rr->reply_bf = in->reply_bf;
- }
- else
- {
- GNUNET_CONTAINER_bloomfilter_or2 (rr->reply_bf,
- in->reply_bf);
- GNUNET_CONTAINER_bloomfilter_free (in->reply_bf);
- }
- GNUNET_free (in);
- return GNUNET_SYSERR;
-}
-
-
-/**
- * Add a new entry to our routing table.
- *
- * @param sender peer that originated the request
- * @param type type of the block
- * @param options options for processing
- * @param key key for the content
- * @param xquery extended query
- * @param xquery_size number of bytes in @a xquery
- * @param reply_bf bloomfilter to filter duplicates
- * @param reply_bf_mutator mutator for @a reply_bf
- */
-void
-GDS_ROUTING_add (const struct GNUNET_PeerIdentity *sender,
- enum GNUNET_BLOCK_Type type,
- enum GNUNET_DHT_RouteOption options,
- const struct GNUNET_HashCode * key, const void *xquery,
- size_t xquery_size,
- const struct GNUNET_CONTAINER_BloomFilter *reply_bf,
- uint32_t reply_bf_mutator)
-{
- struct RecentRequest *recent_req;
-
- while (GNUNET_CONTAINER_heap_get_size (recent_heap) >= DHT_MAX_RECENT)
- expire_oldest_entry ();
- GNUNET_STATISTICS_update (GDS_stats,
- gettext_noop ("# Entries added to routing table"),
- 1, GNUNET_NO);
- recent_req = GNUNET_malloc (sizeof (struct RecentRequest) + xquery_size);
- recent_req->peer = *sender;
- recent_req->key = *key;
- recent_req->reply_bf = GNUNET_CONTAINER_bloomfilter_copy (reply_bf);
- recent_req->type = type;
- recent_req->options = options;
- recent_req->xquery = &recent_req[1];
- memcpy (&recent_req[1], xquery, xquery_size);
- recent_req->xquery_size = xquery_size;
- recent_req->reply_bf_mutator = reply_bf_mutator;
- if (GNUNET_SYSERR ==
- GNUNET_CONTAINER_multihashmap_get_multiple (recent_map, key,
- &try_combine_recent, recent_req))
- {
- GNUNET_STATISTICS_update (GDS_stats,
- gettext_noop
- ("# DHT requests combined"),
- 1, GNUNET_NO);
- return;
- }
- recent_req->heap_node =
- GNUNET_CONTAINER_heap_insert (recent_heap, recent_req,
- GNUNET_TIME_absolute_get ().abs_value_us);
- GNUNET_CONTAINER_multihashmap_put (recent_map, key, recent_req,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
-
-
}
void
GDS_ROUTING_init ()
{
- recent_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
- recent_map = GNUNET_CONTAINER_multihashmap_create (DHT_MAX_RECENT * 4 / 3, GNUNET_NO);
+ routing_table = GNUNET_CONTAINER_multipeermap_create (DHT_MAX_RECENT * 4 / 3, GNUNET_NO);
}
void
GDS_ROUTING_done ()
{
- while (GNUNET_CONTAINER_heap_get_size (recent_heap) > 0)
- expire_oldest_entry ();
- GNUNET_assert (0 == GNUNET_CONTAINER_heap_get_size (recent_heap));
- GNUNET_CONTAINER_heap_destroy (recent_heap);
- recent_heap = NULL;
- GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (recent_map));
- GNUNET_CONTAINER_multihashmap_destroy (recent_map);
- recent_map = NULL;
+ GNUNET_assert (0 == GNUNET_CONTAINER_multipeermap_size (routing_table));
+ GNUNET_CONTAINER_multipeermap_destroy (routing_table);
}
-/* end of gnunet-service-dht_routing.c */
+/* end of gnunet-service-xdht_routing.c */
\ No newline at end of file