/*
This file is part of GNUnet.
- Copyright (C) 2009-2015 Christian Grothoff (and other contributing authors)
+ Copyright (C) 2009-2015 GNUnet e.V.
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
You should have received a copy of the GNU General Public License
along with GNUnet; see the file COPYING. If not, write to the
- Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA.
+ Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA.
*/
/**
* @file dht/gnunet-service-wdht_neighbours.c
* @brief GNUnet DHT service's finger and friend table management code
* @author Supriti Singh
+ * @author Christian Grothoff
+ * @author Arthur Dewarumez
+ *
+ * TODO:
+ * - initiate finding of successors
*/
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet-service-wdht_datacache.h"
#include "gnunet-service-wdht_neighbours.h"
#include "gnunet-service-wdht_nse.h"
-#include <fenv.h>
-#include <stdlib.h>
-#include <string.h>
#include "dht.h"
#define DEBUG(...) \
*/
struct FriendInfo;
+/**
+ *
+ */
+struct FingerTable;
/**
* Information we keep per trail.
struct Trail
{
+ /**
+ * Identifier of the trail with the predecessor.
+ */
+ struct GNUNET_HashCode pred_id;
+
+ /**
+ * Identifier of the trail with the successor.
+ */
+ struct GNUNET_HashCode succ_id;
+
+ /**
+ * When does this trail expire.
+ */
+ struct GNUNET_TIME_Absolute expiration_time;
+
/**
* MDLL entry in the list of all trails with the same predecessor.
*/
*/
struct FriendInfo *succ;
- /**
- * Identifier of the trail with the predecessor.
- */
- struct GNUNET_HashCode pred_id;
-
- /**
- * Identifier of the trail with the successor.
- */
- struct GNUNET_HashCode succ_id;
-
- /**
- * When does this trail expire.
- */
- struct GNUNET_TIME_Absolute expiration_time;
-
/**
* Location of this trail in the heap.
*/
/**
* If this peer started the to create a Finger (and thus @e pred is
- * NULL), this is the Finger we are trying to intialize.
+ * NULL), this is the finger table of the finger we are trying to
+ * intialize.
*/
- struct Finger **finger;
+ struct FingerTable *ft;
+
+ /**
+ * If this peer started the trail to create a Finger (and thus @e
+ * pred is NULL), this is the offset of the finger we are trying to
+ * intialize in the unsorted array.
+ */
+ unsigned int finger_off;
};
};
-/**
- *
- */
-struct FingerTable;
-
-
/**
*
*/
*/
struct Finger **fingers;
- /**
- * Array of sorted fingers (sorted by destination, valid fingers first).
- */
- struct Finger **sorted_fingers;
-
/**
* Size of the finger array.
*/
unsigned int finger_array_size;
/**
- * Number of valid entries in @e sorted_fingers (contiguous from offset 0)
+ * Number of valid entries in @e fingers
*/
unsigned int number_valid_fingers;
struct FindSuccessorMessage
{
/**
- * Type: #GNUNET_MESSAGE_TYPE_WDHT_FIND_SUCCESSOR
+ * Type: #GNUNET_MESSAGE_TYPE_WDHT_SUCCESSOR_FIND
*/
struct GNUNET_MessageHeader header;
*/
uint32_t reserved GNUNET_PACKED;
- /**
- * Unique (random) identifier this peer will use to
- * identify the finger (in future messages).
- */
- struct GNUNET_HashCode trail_id;
-
/**
* Key for which we would like close values returned.
* identify the finger (in future messages).
struct GNUNET_MessageHeader header;
/**
- * The type for the data.
+ * The type for the data in NBO.
*/
uint32_t type GNUNET_PACKED;
*/
uint32_t put_path_length GNUNET_PACKED;
- /**
- * Length of the GET path that follows (if tracked).
- */
- uint32_t get_path_length GNUNET_PACKED;
-
- /**
- * Peer which queried for get and should get the result.
- */
- struct GNUNET_PeerIdentity querying_peer;
-
/**
* When does the content expire?
*/
- struct GNUNET_TIME_Absolute expiration_time;
+ struct GNUNET_TIME_AbsoluteNBO expiration_time;
/**
* The key of the corresponding GET request.
/* put path (if tracked) */
- /* get path (if tracked) */
-
/* Payload */
};
{
// find closest finger(s) on all layers
// use TrailRoute with PeerGetMessage embedded to contact peer
+ // NOTE: actually more complicated, see paper!
}
}
GNUNET_break (trail ==
GNUNET_CONTAINER_heap_remove_node (trail->hn));
- finger = *trail->finger;
+ finger = trail->ft->fingers[trail->finger_off];
if (NULL != finger)
{
- *trail->finger = NULL;
+ trail->ft->fingers[trail->finger_off] = NULL;
+ trail->ft->number_valid_fingers--;
GNUNET_free (finger);
}
GNUNET_free (trail);
}
+/**
+ * Forward the given payload message along the trail.
+ *
+ * @param next_target which direction along the trail should we forward
+ * @param trail_id which trail should we forward along
+ * @param have_path do we track the forwarding path?
+ * @param predecessor which peer do we tack on to the path?
+ * @param path path the message has taken so far along the trail
+ * @param path_length number of entries in @a path
+ * @param payload payload of the message
+ */
+static void
+forward_message_on_trail (struct FriendInfo *next_target,
+ const struct GNUNET_HashCode *trail_id,
+ int have_path,
+ const struct GNUNET_PeerIdentity *predecessor,
+ const struct GNUNET_PeerIdentity *path,
+ uint16_t path_length,
+ const struct GNUNET_MessageHeader *payload)
+{
+ struct GNUNET_MQ_Envelope *env;
+ struct TrailRouteMessage *trm;
+ struct GNUNET_PeerIdentity *new_path;
+ unsigned int plen;
+ uint16_t payload_len;
+
+ payload_len = ntohs (payload->size);
+ if (have_path)
+ {
+ plen = path_length + 1;
+ if (plen >= (GNUNET_SERVER_MAX_MESSAGE_SIZE
+ - payload_len
+ - sizeof (struct TrailRouteMessage))
+ / sizeof (struct GNUNET_PeerIdentity))
+ {
+ /* Should really not have paths this long... */
+ GNUNET_break_op (0);
+ plen = 0;
+ have_path = 0;
+ }
+ }
+ else
+ {
+ GNUNET_break_op (0 == path_length);
+ path_length = 0;
+ plen = 0;
+ }
+ env = GNUNET_MQ_msg_extra (trm,
+ payload_len +
+ plen * sizeof (struct GNUNET_PeerIdentity),
+ GNUNET_MESSAGE_TYPE_WDHT_TRAIL_ROUTE);
+ trm->record_path = htons (have_path);
+ trm->path_length = htons (plen);
+ trm->trail_id = *trail_id;
+ new_path = (struct GNUNET_PeerIdentity *) &trm[1];
+ if (have_path)
+ {
+ memcpy (new_path,
+ path,
+ path_length * sizeof (struct GNUNET_PeerIdentity));
+ new_path[path_length] = *predecessor;
+ }
+ memcpy (&new_path[plen],
+ payload,
+ payload_len);
+ GNUNET_MQ_send (next_target->mq,
+ env);
+}
+
+
/**
* Send the get result to requesting client.
*
* @param trail_id trail identifying where to send the result to, NULL for us
+ * @param options routing options (from GET request)
* @param key Key of the requested data.
* @param type Block type
* @param put_path_length Number of peers in @a put_path
*/
void
GDS_NEIGHBOURS_send_get_result (const struct GNUNET_HashCode *trail_id,
+ enum GNUNET_DHT_RouteOption options,
const struct GNUNET_HashCode *key,
enum GNUNET_BLOCK_Type type,
unsigned int put_path_length,
const void *data,
size_t data_size)
{
- // TRICKY: need to introduce some context to remember trail from
- // the lookup...
+ struct GNUNET_MessageHeader *payload;
+ struct Trail *trail;
+
+ trail = GNUNET_CONTAINER_multihashmap_get (trail_map,
+ trail_id);
+ if (NULL == trail)
+ {
+ /* TODO: inform statistics */
+ return;
+ }
+ if (NULL == trail->pred)
+ {
+ /* result is for *us* (local client) */
+ GDS_CLIENTS_handle_reply (expiration,
+ key,
+ 0, NULL,
+ put_path_length, put_path,
+ type,
+ data_size,
+ data);
+ return;
+ }
+
+ payload = GNUNET_malloc(sizeof(struct GNUNET_MessageHeader) + data_size);
+ payload->size = data_size;
+ payload->type = GNUNET_MESSAGE_TYPE_WDHT_GET_RESULT;
+
+ forward_message_on_trail (trail->pred,
+ trail_id,
+ 0 != (options & GNUNET_DHT_RO_RECORD_ROUTE),
+ &my_identity,
+ NULL, 0,
+ payload);
+ GNUNET_free (payload);
}
}
+/**
+ * Function called with a random friend to be returned.
+ *
+ * @param cls a `struct FriendInfo **` with where to store the result
+ * @param peer the peer identity of the friend (ignored)
+ * @param value the `struct FriendInfo *` that was selected at random
+ * @return #GNUNET_OK (all good)
+ */
+static int
+pick_random_helper (void *cls,
+ const struct GNUNET_PeerIdentity *peer,
+ void *value)
+{
+ struct FriendInfo **fi = cls;
+ struct FriendInfo *v = value;
+
+ *fi = v;
+ return GNUNET_OK;
+}
+
+
/**
* Pick random friend from friends for random walk.
+ *
+ * @return NULL if we have no friends
*/
static struct FriendInfo *
pick_random_friend ()
{
- // TODO: need to extend peermap API to return random entry...
- // (Note: same extension exists for hashmap API).
- return NULL; // FIXME...
+ struct FriendInfo *ret;
+
+ ret = NULL;
+ if (0 ==
+ GNUNET_CONTAINER_multipeermap_get_random (friends_peermap,
+ &pick_random_helper,
+ &ret))
+ return NULL;
+ return ret;
}
* possibly initiate cleanup.
*
* @param cls NULL
- * @param tc unused
*/
static void
-trail_timeout_callback (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
+trail_timeout_callback (void *cls)
{
struct Trail *trail;
struct GNUNET_TIME_Relative left;
}
+/**
+ * Compute how big our finger arrays should be (at least).
+ *
+ * @return size of the finger array, never 0
+ */
+static unsigned int
+get_desired_finger_array_size ()
+{
+ /* FIXME: This is just a stub... */
+ return 64;
+}
+
+
/**
* Initiate a random walk.
*
* @param cls NULL
- * @param tc unused
*/
static void
-do_random_walk (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
+do_random_walk (void *cls)
{
static unsigned int walk_layer;
struct FriendInfo *friend;
struct FingerTable *ft;
struct Finger *finger;
struct Trail *trail;
+ unsigned int nsize;
random_walk_task = NULL;
friend = pick_random_friend ();
delete_trail (finger->trail,
GNUNET_NO,
GNUNET_YES);
- if (ft->finger_array_size < 42)
- {
- // FIXME: must have finger array of the right size here,
- // FIXME: growing / shrinking are tricy -- with pointers
- // from Trails!!!
- }
-
+ if (ft->finger_array_size < (nsize = get_desired_finger_array_size()) )
+ GNUNET_array_grow (ft->fingers,
+ ft->finger_array_size,
+ nsize);
GNUNET_assert (NULL == ft->fingers[ft->walk_offset]);
-
+ trail->ft = ft;
+ trail->finger_off = ft->walk_offset;
finger = GNUNET_new (struct Finger);
finger->trail = trail;
- trail->finger = &ft->fingers[ft->walk_offset];
finger->ft = ft;
ft->fingers[ft->walk_offset] = finger;
ft->is_sorted = GNUNET_NO;
+ ft->number_valid_fingers++;
ft->walk_offset = (ft->walk_offset + 1) % ft->finger_array_size;
walk_layer = (walk_layer + 1) % NUMBER_LAYERED_ID;
const struct RandomWalkMessage *m;
struct Trail *t;
struct FriendInfo *pred;
+ uint16_t layer;
m = (const struct RandomWalkMessage *) message;
+ layer = ntohs (m->layer);
+ if (layer > NUMBER_LAYERED_ID)
+ {
+ GNUNET_break_op (0);
+ return GNUNET_SYSERR;
+ }
pred = GNUNET_CONTAINER_multipeermap_get (friends_peermap,
peer);
t = GNUNET_new (struct Trail);
/* We are the last hop, generate response */
struct GNUNET_MQ_Envelope *env;
struct RandomWalkResponseMessage *rwrm;
- uint16_t layer;
env = GNUNET_MQ_msg (rwrm,
GNUNET_MESSAGE_TYPE_WDHT_RANDOM_WALK_RESPONSE);
rwrm->reserved = htonl (0);
rwrm->trail_id = m->trail_id;
- layer = ntohs (m->layer);
if (0 == layer)
(void) GDS_DATACACHE_get_random_key (&rwrm->location);
else
{
struct FingerTable *ft;
- if (layer > NUMBER_LAYERED_ID)
- {
- GNUNET_break_op (0);
- // FIXME: clean up 't'...
- return GNUNET_SYSERR;
- }
ft = &fingers[layer-1];
if (0 == ft->number_valid_fingers)
{
else
{
struct Finger *f;
+ unsigned int off;
+ unsigned int i;
- f = ft->fingers[GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
- ft->number_valid_fingers)];
+ off = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
+ ft->number_valid_fingers);
+ for (i=0; (NULL == (f = ft->fingers[i])) || (off > 0); i++)
+ if (NULL != f) off--;
rwrm->location = f->destination;
}
}
/**
- * Handle a `struct RandomWalkResponseMessage` from a GNUNET_MESSAGE_TYPE_WDHT_RANDOM_WALK_RESPONSE
- * message.
+ * Handle a `struct RandomWalkResponseMessage`.
*
* @param cls closure (NULL)
* @param peer sender identity
const struct GNUNET_MessageHeader *message)
{
const struct RandomWalkResponseMessage *rwrm;
+ struct Trail *trail;
+ struct FriendInfo *pred;
+ struct FingerTable *ft;
+ struct Finger *finger;
rwrm = (const struct RandomWalkResponseMessage *) message;
- // 1) lookup trail => find Finger entry => fill in 'destination' and mark valid, move to end of sorted array, mark unsorted, update links from 'trails'
+ trail = GNUNET_CONTAINER_multihashmap_get (trail_map,
+ &rwrm->trail_id);
+ if (NULL == trail)
+ {
+ /* TODO: log/statistics: we didn't find the trail (can happen) */
+ return GNUNET_OK;
+ }
+ if (NULL != (pred = trail->pred))
+ {
+ /* We are not the first hop, keep forwarding */
+ struct GNUNET_MQ_Envelope *env;
+ struct RandomWalkResponseMessage *rwrm2;
+
+ env = GNUNET_MQ_msg (rwrm2,
+ GNUNET_MESSAGE_TYPE_WDHT_RANDOM_WALK_RESPONSE);
+ rwrm2->reserved = htonl (0);
+ rwrm2->location = rwrm->location;
+ rwrm2->trail_id = trail->pred_id;
+ GNUNET_MQ_send (pred->mq,
+ env);
+ return GNUNET_OK;
+ }
+ /* We are the first hop, complete finger */
+ if (NULL == (ft = trail->ft))
+ {
+ /* Eh, why did we create the trail if we have no FT? */
+ GNUNET_break (0);
+ delete_trail (trail,
+ GNUNET_NO,
+ GNUNET_YES);
+ return GNUNET_OK;
+ }
+ if (NULL == (finger = ft->fingers[trail->finger_off]))
+ {
+ /* Eh, finger got deleted, but why not the trail as well? */
+ GNUNET_break (0);
+ delete_trail (trail,
+ GNUNET_NO,
+ GNUNET_YES);
+ return GNUNET_OK;
+ }
+
+
+ // 1) lookup trail => find Finger entry => fill in 'destination' and mark valid, move to end of sorted array,
+ //mark unsorted, update links from 'trails'
/*
* Steps :
* 1 check if we are the correct layer
struct Trail *trail;
tdm = (const struct TrailDestroyMessage *) message;
-
- /* Retreive the trail from the trail_map */
- trail = GNUNET_CONTAINER_multihashmap_get(trail_map, tdm->trail_id);
-
- if(peer == trail->pred_id){
- delete(trail, GNUNET_NO, GNUNET_YES);
- }
- else{
- delete(trail, GNUNET_YES, GNUNET_NO);
- }
-
- return GNUNET_OK;
-}
-
-
-/**
- * Handler for a message we received along some trail.
- *
- * @param cls closure
- * @param trail_id trail identifier
- * @param message the message we got
- * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
- */
-typedef int
-(*TrailHandlerCallback)(void *cls,
- const struct GNUNET_HashCode *trail_id,
- const struct GNUNET_MessageHandler *message);
-
-
-/**
- * Definition of a handler for a message received along some trail.
- */
-struct TrailHandler
-{
- /**
- * NULL for end-of-list.
- */
- TrailHandlerCallback callback;
-
- /**
- * Closure for @e callback.
- */
- void *cls;
-
- /**
- * Message type this handler addresses.
- */
- uint16_t message_type;
-
- /**
- * Use 0 for variable-size.
- */
- uint16_t message_size;
-};
-
-
-/**
- * Handle a `struct TrailRouteMessage`.
- *
- * @param cls closure (NULL)
- * @param peer sender identity
- * @param message the finger destroy message
- * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
- */
-static int
-handle_dht_p2p_trail_route (void *cls,
- const struct GNUNET_PeerIdentity *peer,
- const struct GNUNET_MessageHeader *message)
-{
- const struct TrailRouteMessage *trm;
- const void *payload;
- size_t msize;
- unsigned int start_payload;
-
- /* msize = ntohs (message->size); */
- /* if (msize < sizeof (struct TrailRouteMessage)) */
- /* { */
- /* GNUNET_break_op (0); */
- /* return GNUNET_YES; */
- /* } */
-
- /* trm = (const struct TrailRouteMessage *) message; */
- /* /\* Retreive payload *\/ */
- /* start_payload = sizeof (struct PeerGetResultMessage); */
- /* payload = message[start_payload]; */
-
+ trail = GNUNET_CONTAINER_multihashmap_get (trail_map,
+ &tdm->trail_id);
+ delete_trail (trail,
+ ( (NULL != trail->succ) &&
+ (0 == memcmp (peer,
+ &trail->succ->id,
+ sizeof (struct GNUNET_PeerIdentity))) ),
+ ( (NULL != trail->pred) &&
+ (0 == memcmp (peer,
+ &trail->pred->id,
+ sizeof (struct GNUNET_PeerIdentity))) ));
return GNUNET_OK;
}
*
* @param cls closure (NULL)
* @param trail_id path to the originator
+ * @param trail_path path the message took on the trail, if available
+ * @param trail_path_length number of entries on the @a trail_path
* @param message the finger setup message
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
static int
handle_dht_p2p_successor_find (void *cls,
const struct GNUNET_HashCode *trail_id,
+ const struct GNUNET_PeerIdentity *trail_path,
+ unsigned int trail_path_length,
const struct GNUNET_MessageHeader *message)
{
const struct FindSuccessorMessage *fsm;
+ /* We do not expect to track trails for the forward-direction
+ of successor finding... */
+ GNUNET_break_op (0 == trail_path_length);
fsm = (const struct FindSuccessorMessage *) message;
- // locate trail (for sending reply), if not exists, fail nicely.
- // otherwise, go to datacache and return 'top k' elements closest to 'key'
- // as "PUT" messages via the trail (need to extend DB API!)
-#if 0
GDS_DATACACHE_get_successors (trail_id,
- key);
-#endif
+ &fsm->key);
return GNUNET_OK;
}
*
* @param cls closure (NULL)
* @param trail_id path to the originator
+ * @param trail_path path the message took on the trail, if available
+ * @param trail_path_length number of entries on the @a trail_path
* @param message the peer get message
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
static int
handle_dht_p2p_peer_get (void *cls,
const struct GNUNET_HashCode *trail_id,
+ const struct GNUNET_PeerIdentity *trail_path,
+ unsigned int trail_path_length,
const struct GNUNET_MessageHeader *message)
{
const struct PeerGetMessage *pgm;
*
* @param cls closure (NULL)
* @param trail_id path to the originator
+ * @param trail_path path the message took on the trail, if available
+ * @param trail_path_length number of entries on the @a trail_path
* @param message the peer get result message
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
static int
handle_dht_p2p_peer_get_result (void *cls,
const struct GNUNET_HashCode *trail_id,
+ const struct GNUNET_PeerIdentity *trail_path,
+ unsigned int trail_path_length,
const struct GNUNET_MessageHeader *message)
{
const struct PeerGetResultMessage *pgrm;
*
* @param cls closure (NULL)
* @param trail_id path to the originator
+ * @param trail_path path the message took on the trail, if available
+ * @param trail_path_length number of entries on the @a trail_path
* @param message the peer put message
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
static int
handle_dht_p2p_peer_put (void *cls,
const struct GNUNET_HashCode *trail_id,
+ const struct GNUNET_PeerIdentity *trail_path,
+ unsigned int trail_path_length,
const struct GNUNET_MessageHeader *message)
{
const struct PeerGetResultMessage *pgrm;
#if 0
GDS_DATACACHE_handle_put (expiration_time,
key,
- path_length, path,
+ combined_path_length, combined_path,
block_type,
data_size,
data);
GDS_CLIENTS_process_put (options,
block_type,
0, 0,
- path_length, path,
+ combined_path_length, combined_path,
expiration_time,
key,
data,
}
+/**
+ * Handler for a message we received along some trail.
+ *
+ * @param cls closure
+ * @param trail_id trail identifier
+ * @param trail_path path the message took on the trail, if available
+ * @param trail_path_length number of entries on the @a trail_path
+ * @param message the message we got
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+typedef int
+(*TrailHandlerCallback)(void *cls,
+ const struct GNUNET_HashCode *trail_id,
+ const struct GNUNET_PeerIdentity *trail_path,
+ unsigned int trail_path_length,
+ const struct GNUNET_MessageHeader *message);
+
+
+/**
+ * Definition of a handler for a message received along some trail.
+ */
+struct TrailHandler
+{
+ /**
+ * NULL for end-of-list.
+ */
+ TrailHandlerCallback callback;
+
+ /**
+ * Closure for @e callback.
+ */
+ void *cls;
+
+ /**
+ * Message type this handler addresses.
+ */
+ uint16_t message_type;
+
+ /**
+ * Use 0 for variable-size.
+ */
+ uint16_t message_size;
+};
+
+
+/**
+ * Handle a `struct TrailRouteMessage`.
+ *
+ * @param cls closure (NULL)
+ * @param peer sender identity
+ * @param message the finger destroy message
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+static int
+handle_dht_p2p_trail_route (void *cls,
+ const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message)
+{
+ static const struct TrailHandler handlers[] = {
+ { &handle_dht_p2p_successor_find, NULL,
+ GNUNET_MESSAGE_TYPE_WDHT_SUCCESSOR_FIND,
+ sizeof (struct FindSuccessorMessage) },
+ { &handle_dht_p2p_peer_get, NULL,
+ GNUNET_MESSAGE_TYPE_WDHT_GET,
+ 0 },
+ { &handle_dht_p2p_peer_get_result, NULL,
+ GNUNET_MESSAGE_TYPE_WDHT_GET_RESULT,
+ 0 },
+ { &handle_dht_p2p_peer_put, NULL,
+ GNUNET_MESSAGE_TYPE_WDHT_PUT,
+ 0 },
+ { NULL, NULL, 0, 0 }
+ };
+ unsigned int i;
+ const struct TrailRouteMessage *trm;
+ const struct GNUNET_PeerIdentity *path;
+ uint16_t path_length;
+ const struct GNUNET_MessageHeader *payload;
+ const struct TrailHandler *th;
+ struct Trail *trail;
+ size_t msize;
+
+ /* Parse and check message is well-formed */
+ msize = ntohs (message->size);
+ if (msize < sizeof (struct TrailRouteMessage))
+ {
+ GNUNET_break_op (0);
+ return GNUNET_YES;
+ }
+ trm = (const struct TrailRouteMessage *) message;
+ path_length = ntohs (trm->path_length);
+ if (msize < sizeof (struct TrailRouteMessage) +
+ path_length * sizeof (struct GNUNET_PeerIdentity) +
+ sizeof (struct GNUNET_MessageHeader) )
+ {
+ GNUNET_break_op (0);
+ return GNUNET_YES;
+ }
+ path = (const struct GNUNET_PeerIdentity *) &trm[1];
+ payload = (const struct GNUNET_MessageHeader *) &path[path_length];
+ if (msize != (ntohs (payload->size) +
+ sizeof (struct TrailRouteMessage) +
+ path_length * sizeof (struct GNUNET_PeerIdentity)))
+ {
+ GNUNET_break_op (0);
+ return GNUNET_YES;
+ }
+
+ /* Is this message for us? */
+ trail = GNUNET_CONTAINER_multihashmap_get (trail_map,
+ &trm->trail_id);
+ if ( (NULL != trail->pred) &&
+ (0 == memcmp (peer,
+ &trail->pred->id,
+ sizeof (struct GNUNET_PeerIdentity))) )
+ {
+ /* forward to 'successor' */
+ if (NULL != trail->succ)
+ {
+ forward_message_on_trail (trail->succ,
+ &trail->succ_id,
+ ntohs (trm->record_path),
+ peer,
+ path,
+ path_length,
+ payload);
+ return GNUNET_OK;
+ }
+ }
+ else
+ {
+ /* forward to 'predecessor' */
+ GNUNET_break_op ( (NULL != trail->succ) &&
+ (0 == memcmp (peer,
+ &trail->succ->id,
+ sizeof (struct GNUNET_PeerIdentity))) );
+ if (NULL != trail->pred)
+ {
+ forward_message_on_trail (trail->pred,
+ &trail->pred_id,
+ ntohs (trm->record_path),
+ peer,
+ path,
+ path_length,
+ payload);
+ return GNUNET_OK;
+ }
+ }
+
+ /* Message is for us, dispatch to handler */
+ th = NULL;
+ for (i=0; NULL != handlers[i].callback; i++)
+ {
+ th = &handlers[i];
+ if (ntohs (payload->type) == th->message_type)
+ {
+ if ( (0 == th->message_size) ||
+ (ntohs (payload->size) == th->message_size) )
+ th->callback (th->cls,
+ &trm->trail_id,
+ path,
+ path_length,
+ payload);
+ else
+ GNUNET_break_op (0);
+ break;
+ }
+ }
+ GNUNET_break_op (NULL != th);
+ return GNUNET_OK;
+}
+
+
/**
* Initialize neighbours subsystem.
+ *
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
int
projects / oweals / gnunet.git / blobdiff