#include <fenv.h>
#include "dht.h"
+/**
+ * FIXME:
+ * 1. In X-Vine paper, there is no policy defined for replicating the data to
+ * recover in case of peer failure. We can do it in Chord way. In R5N, the key
+ * is hashed and then data is stored according to the key value generated after
+ * hashing.
+ * 2. We will keep an entry in routing table even if its a friend for the moment.
+ * Because I am not sure if there is a case where it will not work.
+ * Trail id we can keep but actually there is no trail.
+ */
+
/**
* Maximum possible fingers (including predecessor) of a peer
*/
#define DHT_FIND_FINGER_TRAIL_INTERVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)
/**
- * How long at most to wait for transmission of a request to another peer?
+ * How long at most to wait for transmission of a request to a friend ?
*/
#define GET_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 2)
/**
* Maximum number of trails stored per finger.
*/
-#define MAXIMUM_TRAILS_PER_FINGER 2
+#define MAXIMUM_TRAILS_PER_FINGER 1
/**
- * Finger map index for predecessor entry in finger peermap.
+ * Finger map index for predecessor entry in finger table.
*/
#define PREDECESSOR_FINGER_ID 64
/**
* Wrap around in peer identity circle.
- * FIXME: not used anywhere, should be used in
- * find_successor() while comparing two peers.
*/
#define PEER_IDENTITES_WRAP_AROUND pow(2, 64) - 1
/**
+ * FIXME: Its use only at 3 places check if you can remove it.
* To check if a finger is predecessor or not.
*/
enum GDS_NEIGHBOURS_finger_type
struct GNUNET_MessageHeader header;
/**
- * Is source_peer trying to setup the trail to any finger or predecessor.
+ * Is source_peer trying to setup the trail to a predecessor or any finger.
*/
uint32_t is_predecessor;
/**
* Peer closest to this value will be our finger.
*/
- uint64_t ultimate_destination_finger_value;
+ uint64_t final_destination_finger_value;
/**
* Source peer which wants to setup the trail to one of its finger.
struct GNUNET_PeerIdentity best_known_destination;
/**
- * Trail id of any intermediate trail we may encounter while doing trail setup.
+ * In case best_known_destination is a finger, then trail id of trail to
+ * reach to this finger.
*/
struct GNUNET_HashCode intermediate_trail_id;
/* List of peers which are part of trail setup so far.
* Trail does NOT include source_peer and peer which will be closest to
* ultimate_destination_finger_value.
- * struct GNUNET_PeerIdentity trail_list[]
+ * struct GNUNET_PeerIdentity trail[]
*/
};
};
/**
- * FIXME: In case you append the trail it may contain the same peer twice.
- * So, when you call search_my_index it can return error. Solution is while
- * appending the entry first check for duplicate entries or may be don't
- * send the current_predecessor at all.
* P2P Verify Successor Result Message
*/
struct PeerVerifySuccessorResultMessage
/**
* Successor to which PeerVerifySuccessorMessage was sent.
*/
- struct GNUNET_PeerIdentity source_successor;
+ struct GNUNET_PeerIdentity current_successor;
/**
* Current Predecessor of source_successor. It can be same as querying peer
- * or different.
+ * or different. In case it is different then it can be querying_peer's
+ * probable successor.
*/
- struct GNUNET_PeerIdentity current_predecessor;
+ struct GNUNET_PeerIdentity probable_successor;
/**
- * Trail identifier of trail from querying_peer to source_successor.
+ * Trail identifier of trail from querying_peer to current_successor.
*/
struct GNUNET_HashCode trail_id;
*/
uint32_t trail_direction;
- /* In case current_predecessor != querying_peer, then trail to reach from
- * querying_peer to current_predecessor, NOT including end points.
+ /* In case probable_successor != querying_peer, then trail to reach from
+ * querying_peer to probable_successor, NOT including end points.
* struct GNUNET_PeerIdentity trail[]
*/
};
};
/**
- * FIXME: Check if you can merge trail compression and trail teardown
- * by modifying routing table structure a little bit. PRIORITY: at the end
- * less code.
* P2P Trail Compression Message.
*/
struct PeerTrailCompressionMessage
*/
struct GNUNET_PeerIdentity source_peer;
- /**
- * Destination of this trail.
- */
- struct GNUNET_PeerIdentity destination_peer;
-
/**
* Trail from source_peer to destination_peer compressed such that
* new_first_friend is the first hop in the trail from source to
*/
struct GNUNET_MessageHeader header;
- /**
- * Source peer of the trail.
- */
- struct GNUNET_PeerIdentity source_peer;
-
- /**
- * Destination peer of the trail.
- */
- struct GNUNET_PeerIdentity destination_peer;
-
/**
* Unique identifier of the trail.
*/
- struct GNUNET_HashCode TRAIL_ID;
+ struct GNUNET_HashCode trail_id;
/**
* Direction of trail.
struct PeerTrailRejectionMessage
{
/**
- * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_REJECTION
+ * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP_REJECTION
*/
struct GNUNET_MessageHeader header;
};
-
/**
* Entry in friend_peermap.
*/
* Length of trail pointed
*/
unsigned int trail_length;
+
+ /**
+ * Is there a valid trail entry.
+ */
+ unsigned int is_present;
};
/**
- * An entry in finger_hashmap.
+ * An entry in finger_table
*/
struct FingerInfo
{
*/
struct GNUNET_PeerIdentity finger_identity;
+ /**
+ * Is any finger stored at this finger index.
+ */
+ unsigned int is_present;
+
/**
* Index in finger peer map
*/
- uint32_t finger_map_index;
+ uint32_t finger_table_index;
/**
* Number of trails setup so far for this finger.
struct Trail trail_list[MAXIMUM_TRAILS_PER_FINGER];
};
+
/**
- * FIXME: Need to check if we need all the fields or not.
* Data structure to keep track of closest peer seen so far in find_successor()
*/
struct Closest_Peer
{
/**
- * 64 bit value of the peer
+ * Destination finger vaule.
*/
- uint64_t value;
-
+ uint64_t destination_finger_value;
+
+ /**
+ * Is finger value predecessor or any other finge
+ */
+ unsigned int is_predecessor;
+
/**
* Trail id to reach to peer.
*/
static struct GNUNET_CONTAINER_MultiPeerMap *friend_peermap;
/**
- * Hash map of all the fingers of a peer
- */
-static struct GNUNET_CONTAINER_MultiHashMap32 *finger_hashmap;
-
-/**
- * FIXME: Check if you can replace finger_hashmap by an array of fingers.
* Array of all the fingers.
- *
-static struct FingerInfo finger_table [MAX_FINGERS];*/
+ */
+static struct FingerInfo finger_table [MAX_FINGERS];
/**
* Handle to CORE.
}
+/**
+ * Return friend corresponding to peer.
+ * @param peer
+ * @return Friend
+ */
+struct FriendInfo *
+GDS_NEIGHBOURS_get_friend (struct GNUNET_PeerIdentity peer)
+{
+ struct FriendInfo *friend;
+ GNUNET_assert (NULL != (friend =
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap, &peer)));
+ return friend;
+}
+
+
/**
* Construct a trail setup message and forward it to target_friend
* @param source_peer Peer which wants to setup the trail
pending->msg = &tsm->header;
tsm->header.size = htons (msize);
tsm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP);
- tsm->ultimate_destination_finger_value = GNUNET_htonll (ultimate_destination_finger_value);
+ tsm->final_destination_finger_value = GNUNET_htonll (ultimate_destination_finger_value);
tsm->source_peer = source_peer;
tsm->best_known_destination = best_known_destination;
tsm->is_predecessor = htonl (is_predecessor);
/**
- * Send trail rejection message to next_hop
+ * Send trail rejection message to target friend
* @param source_peer Peer which is trying to setup the trail.
* @param ultimate_destination_finger_value Peer closest to this value will be
* @a source_peer's finger
trm = (struct PeerTrailRejectionMessage *)&pending[1];
pending->msg = &trm->header;
trm->header.size = htons (msize);
- trm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_REJECTION);
+ trm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP_REJECTION);
trm->source_peer = source_peer;
trm->congested_peer = congested_peer;
trm->congestion_time = congestion_timeout;
void
GDS_NEIGHBOURS_send_verify_successor_message (struct GNUNET_PeerIdentity source_peer,
struct GNUNET_PeerIdentity successor,
- const struct GNUNET_HashCode trail_id,
+ struct GNUNET_HashCode trail_id,
struct GNUNET_PeerIdentity *trail,
unsigned int trail_length,
struct FriendInfo *target_friend)
/**
- * FIXME: check if we can merge send_trail_teardown and trail_compression
- * Construct a trail teardown message and send it to target_friend
- * @param source_peer Source of the trail.
- * @param destination_peer Destination of the trail.
+ * FIXME: In every function we pass target friend except for this one.
+ * so, either change everything or this one. also, should se just store
+ * the pointer to friend in routing table rather than gnunet_peeridentity.
+ * if yes then we should keep friend info in.h andmake lot of changes.
+ * Construct a trail teardown message and forward it to target friend.
* @param trail_id Unique identifier of the trail.
* @param trail_direction Direction of trail.
* @param target_friend Friend to get this message.
*/
void
-GDS_NEIGHBOURS_send_trail_teardown (struct GNUNET_PeerIdentity source_peer,
- struct GNUNET_PeerIdentity destination_peer,
- struct GNUNET_HashCode trail_id,
- enum GDS_ROUTING_trail_direction trail_direction,
- struct FriendInfo *target_friend)
+GDS_NEIGHBOURS_send_trail_teardown (struct GNUNET_HashCode trail_id,
+ unsigned int trail_direction,
+ struct GNUNET_PeerIdentity *peer)
{
struct PeerTrailTearDownMessage *ttdm;
struct P2PPendingMessage *pending;
+ struct FriendInfo *target_friend;
size_t msize;
msize = sizeof (struct PeerTrailTearDownMessage);
GNUNET_break (0);
return;
}
-
+
+ GNUNET_assert (NULL != (target_friend =
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer)));
+
if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
{
GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
pending->msg = &ttdm->header;
ttdm->header.size = htons (msize);
ttdm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_TEARDOWN);
- ttdm->source_peer = source_peer;
- ttdm->destination_peer = destination_peer;
- ttdm->TRAIL_ID = trail_id;
+ ttdm->trail_id = trail_id;
ttdm->trail_direction = htonl (trail_direction);
/* Send the message to chosen friend. */
+
GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
target_friend->pending_count++;
process_friend_queue (target_friend);
*/
void
GDS_NEIGHBOURS_send_verify_successor_result (struct GNUNET_PeerIdentity querying_peer,
- struct GNUNET_PeerIdentity source_successor,
- struct GNUNET_PeerIdentity current_predecessor,
+ struct GNUNET_PeerIdentity current_successor,
+ struct GNUNET_PeerIdentity probable_successor,
struct GNUNET_HashCode trail_id,
const struct GNUNET_PeerIdentity *trail,
unsigned int trail_length,
vsmr->header.size = htons (msize);
vsmr->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_VERIFY_SUCCESSOR_RESULT);
vsmr->querying_peer = querying_peer;
- vsmr->source_successor = source_successor;
- vsmr->current_predecessor = current_predecessor;
+ vsmr->current_successor = current_successor;
+ vsmr->probable_successor = probable_successor;
vsmr->trail_direction = htonl (trail_direction);
vsmr->trail_id = trail_id;
void
GDS_NEIGHBOURS_send_notify_new_successor (struct GNUNET_PeerIdentity source_peer,
struct GNUNET_PeerIdentity successor,
- struct GNUNET_PeerIdentity *successor_trail,
+ const struct GNUNET_PeerIdentity *successor_trail,
unsigned int successor_trail_length,
struct GNUNET_HashCode succesor_trail_id,
struct FriendInfo *target_friend)
GDS_NEIGHBOURS_send_add_trail (struct GNUNET_PeerIdentity source_peer,
struct GNUNET_PeerIdentity destination_peer,
struct GNUNET_HashCode trail_id,
- struct GNUNET_PeerIdentity *trail,
+ const struct GNUNET_PeerIdentity *trail,
unsigned int trail_length,
struct FriendInfo *target_friend)
{
adm->destination_peer = destination_peer;
adm->trail_id = trail_id;
- if (trail_length > 0)
- {
- peer_list = (struct GNUNET_PeerIdentity *)&adm[1];
- memcpy (peer_list, trail, sizeof (struct GNUNET_PeerIdentity) * trail_length);
- }
+ peer_list = (struct GNUNET_PeerIdentity *)&adm[1];
+ memcpy (peer_list, trail, sizeof (struct GNUNET_PeerIdentity) * trail_length);
/* Send the message to chosen friend. */
GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
/**
- * FIXME: Merge into "teardown", add source and "last/new_first" in message struct.
* Construct a trail compression message and send it to target_friend.
* @param source_peer Source of the trail.
- * @param destination_finger Destination of trail.
* @param trail_id Unique identifier of trail.
* @param first_friend First hop in compressed trail to reach from source to finger
* @param target_friend Next friend to get this message.
*/
void
GDS_NEIGHBOURS_send_trail_compression (struct GNUNET_PeerIdentity source_peer,
- struct GNUNET_PeerIdentity destination_peer,
struct GNUNET_HashCode trail_id,
struct GNUNET_PeerIdentity first_friend,
struct FriendInfo *target_friend)
tcm->source_peer = source_peer;
tcm->new_first_friend = first_friend;
tcm->trail_id = trail_id;
- tcm->destination_peer = destination_peer;
GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
target_friend->pending_count++;
/**
+ * FIXME; not handling the wrap around logic correctly.
* Select closest finger to value.
* @param peer1 First peer
* @param peer2 Second peer
struct GNUNET_PeerIdentity *peer2,
uint64_t value)
{
-#if 0
uint64_t peer1_value;
uint64_t peer2_value;
-
+
memcpy (&peer1_value, peer1, sizeof (uint64_t));
memcpy (&peer2_value, peer2, sizeof (uint64_t));
-
- if ((peer1_value <= value) && (value <= peer2_value))
- return peer2;
- else if ((peer2_value <= value) && (value <= peer1_value))
- return peer1;
- else if ((peer1_value <= peer2_value) && (peer2_value <= value))
- return peer1;
- else if ((peer2_value <= peer1_value) && (peer1_value <= value))
- return peer2;
- else if ((value <= peer1_value) && (peer1_value <= peer2_value))
+ if (peer1_value == value)
+ {
return peer1;
- else /*if ((value <= peer2_value) && (peer2_value <= peer1_value))*/
+ }
+
+ if (peer2_value == value)
+ {
return peer2;
-#endif
+ }
+
+ if (peer2_value < peer1_value)
+ {
+ if ((peer2_value < value) && (value < peer1_value))
+ {
+ return peer1;
+ }
+ else if (((peer1_value < value) && (value < PEER_IDENTITES_WRAP_AROUND)) ||
+ ((0 < value) && (value < peer2_value)))
+ {
+ return peer2;
+ }
+ }
+
+ if (peer1_value < peer2_value)
+ {
+ if ((peer1_value < value) && (value < peer2_value))
+ {
+ return peer2;
+ }
+ else if (((peer2_value < value) && (value < PEER_IDENTITES_WRAP_AROUND)) ||
+ ((0 < value) && (value < peer1_value)))
+ {
+ return peer1;
+ }
+ }
return NULL;
}
/**
+ * FIMXE: COMPLETE THE LOGIC.
+ * my_id = 0
+ * finger = 5
+ * key = 3
+ * [0,5) → my_id
+ * [5,0) → finger
+ *
+ * 0 <= key < 5, so my_id 0 is the predecessor.
+ * peer1 != peer2 ever.
* Select closest predecessor to value.
* @param peer1 First peer
* @param peer2 Second peer
struct GNUNET_PeerIdentity *peer2,
uint64_t value)
{
- #if 0
uint64_t peer1_value;
uint64_t peer2_value;
-
+
memcpy (&peer1_value, peer1, sizeof (uint64_t));
memcpy (&peer2_value, peer2, sizeof (uint64_t));
-
-#endif
+
+ if (peer1_value == value)
+ return peer1;
+
+ if (peer2_value == value)
+ return peer2;
+
+ if (peer1_value < peer2_value)
+ {
+ if ((peer1_value < value) && (value < peer2_value))
+ return peer1;
+ else if (((peer2_value < value) && (value < PEER_IDENTITES_WRAP_AROUND)) ||
+ ((PEER_IDENTITES_WRAP_AROUND > value) && (value < peer1_value)))
+ return peer2;
+ }
+
+ if (peer2_value < peer1_value)
+ {
+ if ((peer2_value < value) && (value < peer1_value))
+ return peer2;
+ else if (((peer1_value < value) && (value < PEER_IDENTITES_WRAP_AROUND)) ||
+ ((PEER_IDENTITES_WRAP_AROUND > value) && (value < peer2_value)))
+ return peer1;
+ }
return NULL;
}
+/* FIXME: select closest peer w.r.t. value. [finger->friend_id, current_successor->id)
+ and [current_successor->id, finger->friend_id). Check in which range value lies.
+ Also, check for wrap around. But this will give you the immediate predecessor
+ For example. if we have 0,1,6 and I am 0 and one of my finger is 6. Then
+ for 1, we will have ranges like [0,6) and [6,0) 1 lies in range from [0,6)
+ but successor is 6 not 0 as 6 is > than 1. If you are the closest one,
+ then set the values
+ in current_successor. Want to write a generic code so that it is used in
+ * finger_table_add also while choosing the closest one among new and existing
+ * one. */
+/**
+ * my_id = 0
+ * finger = 5
+ * key = 3
+ * [0,5) → my_id
+ * [5,0) → finger
+
+ * 0 <= key < 5, so key should go to 5.
+
+ */
/**
* Select the closest peer among two peers (which should not be same)
- * with respect to value and finger_map_index
+ * with respect to value and finger_table_index
* @param peer1 First peer
* @param peer2 Second peer
* @param value Value relative to which we find the closest
- * @param finger_map_index Index in finger map. If equal to PREDECESSOR_FINGER_ID,
+ * @param finger_table_index Index in finger map. If equal to PREDECESSOR_FINGER_ID,
* then we use different logic than other
- * finger_map_index
+ * finger_table_index
* @return Closest peer among two peers.
*/
static struct GNUNET_PeerIdentity *
select_closest_peer (struct GNUNET_PeerIdentity *peer1,
struct GNUNET_PeerIdentity *peer2,
uint64_t value,
- unsigned int finger_map_index)
+ unsigned int finger_table_index)
{
struct GNUNET_PeerIdentity *closest_peer;
-
- if (PREDECESSOR_FINGER_ID == finger_map_index)
+ /* FIXME: select closest peer w.r.t. value. [friend_id, current_successor->id)
+ and [current_successor->id, friend_id). Check in which range value lies.
+ Also, check for wrap around. Set the value of current_successor accordingly.*/
+ if (PREDECESSOR_FINGER_ID == finger_table_index)
closest_peer = select_closest_predecessor (peer1, peer2, value);
else
closest_peer = select_closest_finger (peer1, peer2, value);
/**
- * Find the successor for destination_finger_value among my_identity, all my
- * friend and all my fingers. Don't consider friends or fingers
- * which are congested or have crossed the threshold.
- * @param destination_finger_value Peer closest to this value will be the next successor.
- * @param next_destination [out] Updated to friend identity in case a friend is
- * successor, updated to first friend to reach to finger
- * in case finger is the destination.
- * @param new_intermediate_trail_id [out] In case we finger is the @a next_destination,
- * then we updated the field with trail id to reach
- * to that finger.
- * @param finger_map_index Index in finger peermap for which we are
- * looking for a finger, to discern between
- * IS_PREDECESSOR or not.
- * @return Closest successor for value.
+ * FIXME: better names and more refactoring.
+ * Compare FINGER entry with current successor. If finger's first friend of all
+ * its trail is not congested and has not crossed trail threshold, then check
+ * if finger peer identity is closer to final_destination_finger_value than
+ * current_successor. If yes then update current_successor.
+ * @param current_successor[in/out]
+ * @return
*/
-static struct GNUNET_PeerIdentity *
-find_successor (uint64_t destination_finger_value,
- struct GNUNET_PeerIdentity *best_known_destination,
- struct GNUNET_HashCode *new_intermediate_trail_id,
- unsigned int finger_map_index)
+static struct Closest_Peer *
+compare_finger_and_current_successor (struct Closest_Peer *current_closest_peer)
{
- struct Closest_Peer *current_successor;
- struct GNUNET_PeerIdentity *next_hop;
- struct GNUNET_CONTAINER_MultiPeerMapIterator *friend_iter;
- struct GNUNET_CONTAINER_MultiHashMap32Iterator *finger_iter;
- struct Selected_Finger_Trail *finger_trail;
- struct FriendInfo *friend;
struct FingerInfo *finger;
+ struct FriendInfo *friend;
+ struct GNUNET_PeerIdentity *closest_peer;
int i;
- /* Initialize current_successor to my_identity. */
- current_successor = GNUNET_new (struct Closest_Peer);
- memcpy (¤t_successor->value, &my_identity, sizeof (uint64_t));
- memset (¤t_successor->trail_id, 0, sizeof (current_successor->trail_id));
- current_successor->next_hop = my_identity;
- current_successor->best_known_destination = my_identity;
-
- /* Iterate over friend_peermap and compare each friend with current_successor.*/
- friend_iter = GNUNET_CONTAINER_multipeermap_iterator_create (friend_peermap);
- for (i= 0; i < GNUNET_CONTAINER_multipeermap_size (friend_peermap); i++)
+ for (i = 0; i < MAX_FINGERS; i++)
{
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_iterator_next (friend_iter, NULL,
- (const void **)&friend));
+ struct Selected_Finger_Trail *finger_trail;
+ finger = &finger_table[i];
- if (GNUNET_YES == is_friend_congested (friend))
+ if (GNUNET_NO == finger->is_present)
continue;
- /* FIXME: select closest peer w.r.t. value. [friend_id, current_successor->id)
- and [current_successor->id, friend_id). Check in which range value lies.
- Also, check for wrap around. Set the value of current_successor accordingly.*/
- }
-
- /* Iterate over finger_hashmap and compare each finger with current_successor.*/
- finger_iter = GNUNET_CONTAINER_multihashmap32_iterator_create (finger_hashmap);
- for (i = 0; i < GNUNET_CONTAINER_multihashmap32_size (finger_hashmap); i++)
- {
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multihashmap32_iterator_next (finger_iter, NULL,
- (void *)&finger));
+ /* If my identity is same as current closest peer then don't consider me*/
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
+ ¤t_closest_peer->best_known_destination))
+ continue;
/* If I am my own finger, then ignore this finger. */
if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
- &my_identity))
+ &my_identity))
continue;
/* If finger is friend. */
- if(GNUNET_CONTAINER_multipeermap_get (friend_peermap, &finger->finger_identity))
+ if (NULL != (friend = GNUNET_CONTAINER_multipeermap_get
+ (friend_peermap, &finger->finger_identity)))
{
- /* If not congested then compare it with current_successor. */
- if (GNUNET_NO == is_friend_congested (friend))
+ if (GNUNET_YES == is_friend_congested (friend))
+ continue;
+
+ /* If not congested then compare it with current_successor. */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
+ ¤t_closest_peer->best_known_destination))
+ continue;
+
+ closest_peer = select_closest_peer (&finger->finger_identity,
+ ¤t_closest_peer->best_known_destination,
+ current_closest_peer->destination_finger_value,
+ current_closest_peer->is_predecessor);
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
+ closest_peer))
{
- //compare it with current successor.
+ current_closest_peer->best_known_destination = finger->finger_identity;
+ current_closest_peer->next_hop = finger->finger_identity;
}
+ continue;
}
+
/* Choose one of the trail to reach to finger. */
finger_trail = select_finger_trail (finger);
if (NULL == finger_trail)
continue;
- /* FIXME: select closest peer w.r.t. value. [finger->friend_id, current_successor->id)
- and [current_successor->id, finger->friend_id). Check in which range value lies.
- Also, check for wrap around. But this will give you the immediate predecessor
- For example. if we have 0,1,6 and I am 0 and one of my finger is 6. Then
- for 1, we will have ranges like [0,6) and [6,0) 1 lies in range from [0,6)
- but successor is 6 not 0 as 6 is > than 1. If you are the closest one,
- then set the values
- in current_successor. Want to write a generic code so that it is used in
- * finger_table_add also while choosing the closest one among new and existing
- * one. */
+ closest_peer = select_closest_peer (&finger->finger_identity,
+ ¤t_closest_peer->best_known_destination,
+ current_closest_peer->destination_finger_value,
+ current_closest_peer->is_predecessor);
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
+ closest_peer))
+ {
+ current_closest_peer->best_known_destination = finger->finger_identity;
+ current_closest_peer->next_hop = finger_trail->friend.id;
+ current_closest_peer->trail_id = finger_trail->trail_id;
+ }
+ continue;
+ }
+ return current_closest_peer;
+}
+
+
+/**
+ * Compare friend entry with current successor. If friend is not congested and
+ * has not crossed trail threshold, then check if friend peer identity is
+ * closer to final_destination_finger_value than current_successor. If yes
+ * then update current_successor.
+ * @param cls closure
+ * @param key current public key
+ * @param value struct Closest_Peer
+ * @return #GNUNET_YES if we should continue to iterate,
+ * #GNUNET_NO if not.
+ */
+static int
+compare_friend_and_current_closest_peer (void *cls,
+ const struct GNUNET_PeerIdentity *key,
+ void *value)
+{
+ struct FriendInfo *friend = value;
+ struct Closest_Peer *current_closest_peer = cls;
+ struct GNUNET_PeerIdentity *closest_peer;
+
+ if (GNUNET_YES == is_friend_congested (friend))
+ return GNUNET_YES;
+
+ if (0 ==
+ GNUNET_CRYPTO_cmp_peer_identity (&friend->id,
+ ¤t_closest_peer->best_known_destination))
+ return GNUNET_YES;
+
+ closest_peer = select_closest_peer (&friend->id,
+ ¤t_closest_peer->best_known_destination,
+ current_closest_peer->destination_finger_value,
+ current_closest_peer->is_predecessor);
+
+ /* If friend is the closest successor. */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&friend->id, closest_peer))
+ {
+ current_closest_peer->best_known_destination = friend->id;
+ current_closest_peer->next_hop = friend->id;
}
- best_known_destination = ¤t_successor->best_known_destination;
- new_intermediate_trail_id = ¤t_successor->trail_id;
- next_hop = ¤t_successor->next_hop;
+ return GNUNET_YES;
+}
+
+/**
+ * Initialize current_successor to my_identity.
+ * @param my_identity My peer identity
+ * @return current_successor
+ */
+static struct Closest_Peer *
+init_current_successor (struct GNUNET_PeerIdentity my_identity,
+ uint64_t destination_finger_value,
+ unsigned int is_predecessor)
+{
+ struct Closest_Peer *current_closest_peer;
+
+ current_closest_peer = GNUNET_new (struct Closest_Peer);
+ memset (¤t_closest_peer->trail_id, 0, sizeof (current_closest_peer->trail_id));
+ current_closest_peer->destination_finger_value = destination_finger_value;
+ current_closest_peer->is_predecessor = is_predecessor;
+ current_closest_peer->next_hop = my_identity;
+ current_closest_peer->best_known_destination = my_identity;
+
+ return current_closest_peer;
+}
+
+
+/**
+ * FIXME: first check if the finger == closest_peer then don't do anything.
+ * Find the successor for destination_finger_value among my_identity, all my
+ * friend and all my fingers. Don't consider friends or fingers
+ * which are congested or have crossed the threshold.
+ * @param destination_finger_value Peer closest to this value will be the next successor.
+ * @param local_best_known_destination [out] Updated to my_identity if I am the
+ * final destination. Updated to friend
+ * identity in case a friend is successor,
+ * updated to first friend to reach to finger
+ * in case finger is the destination.
+ * @param new_intermediate_trail_id [out] In case a finger is the
+ * @a local_best_known_destination,
+ * then it is the trail to reach it. Else
+ * default set to 0.
+ * @param is_predecessor Are we looking for predecessor or finger?
+ * @return Next hop to reach to local_best_known_destination. In case my_identity
+ * or a friend is a local_best_known_destination, then
+ * next_hop = local_best_known_destination. Else
+ * next_hop is the first friend to reach to finger (local_best_known_destination)
+ */
+static struct GNUNET_PeerIdentity *
+find_successor (uint64_t destination_finger_value,
+ struct GNUNET_PeerIdentity *local_best_known_destination,
+ struct GNUNET_HashCode *new_intermediate_trail_id,
+ unsigned int is_predecessor)
+{
+ struct Closest_Peer *current_closest_peer;
+ struct GNUNET_PeerIdentity *next_hop;
+ /* Initialize current_successor to my_identity. */
+ current_closest_peer = init_current_successor (my_identity,
+ destination_finger_value,
+ is_predecessor);
+
+ /* Compare each friend entry with current_successor and update current_successor
+ * with friend if its closest. */
+ GNUNET_assert (GNUNET_SYSERR !=
+ GNUNET_CONTAINER_multipeermap_iterate (friend_peermap,
+ &compare_friend_and_current_closest_peer,
+ current_closest_peer));
+
+ /* Compare each finger entry with current_successor and update current_successor
+ * with finger if its closest. */
+ compare_finger_and_current_successor (current_closest_peer);
+
+ *local_best_known_destination = current_closest_peer->best_known_destination;
+ new_intermediate_trail_id = ¤t_closest_peer->trail_id;
+ next_hop = GNUNET_new (struct GNUNET_PeerIdentity);
+ *next_hop = current_closest_peer->next_hop;
+
return next_hop;
}
struct P2PPendingMessage *pending;
struct FriendInfo *target_friend;
struct GNUNET_PeerIdentity *pp;
+ struct GNUNET_PeerIdentity *local_best_known_dest;
size_t msize;
msize = put_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size +
struct GNUNET_PeerIdentity *next_hop;
memcpy (&key_value, key, sizeof (uint64_t));
- next_hop = find_successor (key_value, best_known_dest,
+ local_best_known_dest = GNUNET_new (struct GNUNET_PeerIdentity);
+
+ next_hop = find_successor (key_value, local_best_known_dest,
intermediate_trail_id, GDS_FINGER_TYPE_NON_PREDECESSOR);
- if (0 == GNUNET_CRYPTO_cmp_peer_identity(next_hop, &my_identity))
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (local_best_known_dest, &my_identity))
{
/* I am the destination but we have already done datacache_put in client file. */
return;
else
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
}
-
+ else
+ {
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, target_peer);
+ }
pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
pending->timeout = expiration_time;
ppm = (struct PeerPutMessage *) &pending[1];
ppm->desired_replication_level = htonl (desired_replication_level);
ppm->put_path_length = htonl (put_path_length);
ppm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
- ppm->best_known_destination = *best_known_dest;
+ if (NULL == best_known_dest)
+ ppm->best_known_destination = *local_best_known_dest;
+ else
+ ppm->best_known_destination = *best_known_dest;
ppm->key = *key;
if (NULL == intermediate_trail_id)
memset (&ppm->intermediate_trail_id, 0, sizeof (ppm->intermediate_trail_id));
struct PeerGetMessage *pgm;
struct P2PPendingMessage *pending;
struct FriendInfo *target_friend;
+ struct GNUNET_PeerIdentity *local_best_known_dest;
struct GNUNET_PeerIdentity *gp;
size_t msize;
memcpy (&key_value, key, sizeof (uint64_t));
// FIXME: endianess of key_value!?
- /* FIXME: Here you should use enum GDS_NEIGHBOURS_FINGER_TYPE in place of 0. */
- next_hop = find_successor (key_value, best_known_dest,
+ local_best_known_dest = GNUNET_new (struct GNUNET_PeerIdentity);
+ next_hop = find_successor (key_value, local_best_known_dest,
intermediate_trail_id, GDS_FINGER_TYPE_NON_PREDECESSOR);
- if (0 == GNUNET_CRYPTO_cmp_peer_identity(&my_identity,next_hop))
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity,next_hop))
{
GDS_DATACACHE_handle_get (key,block_type, NULL, 0,
NULL, 0, 1, &my_identity, NULL,&my_identity);
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
}
}
+ else
+ {
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, target_peer);
+ }
pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
pending->importance = 0; /* FIXME */
pgm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_GET);
pgm->get_path_length = htonl (get_path_length);
pgm->key = *key;
- pgm->best_known_destination = *best_known_dest;
- pgm->intermediate_trail_id = *intermediate_trail_id;
+ if (NULL != best_known_dest)
+ pgm->best_known_destination = *best_known_dest;
+ else
+ pgm->best_known_destination = *local_best_known_dest;
+
+ if (NULL == intermediate_trail_id)
+ memset (&pgm->intermediate_trail_id, 0, sizeof (pgm->intermediate_trail_id));
+ else
+ pgm->intermediate_trail_id = *intermediate_trail_id;
pgm->hop_count = htonl (hop_count + 1);
if (get_path != 0)
struct FriendInfo *target_friend;
int current_path_index;
size_t msize;
-
+
msize = get_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size +
sizeof (struct PeerPutMessage);
memcpy (&(get_result->querying_peer), source_peer, sizeof (struct GNUNET_PeerIdentity));
get_result->expiration_time = expiration;
- if (get_path_length != 0)
- {
- get_result_path = (struct GNUNET_PeerIdentity *)&get_result[1];
- memcpy (get_result_path, get_path,
+
+ get_result_path = (struct GNUNET_PeerIdentity *)&get_result[1];
+ memcpy (get_result_path, get_path,
sizeof (struct GNUNET_PeerIdentity) * get_path_length);
- }
memcpy (&get_result_path[get_path_length], data, data_size);
/* FIXME: Is this correct? */
&key_ret,
(const void **)&friend));
-
- if ((TRAILS_THROUGH_FRIEND_THRESHOLD == friend->trails_count) &&
+ /* This friend is not congested and has not crossed trail threshold. */
+ if ((TRAILS_THROUGH_FRIEND_THRESHOLD > friend->trails_count) &&
(0 == GNUNET_TIME_absolute_get_remaining (friend->congestion_timestamp).rel_value_us))
{
break;
/**
- * FIXME: pass current_search_finger_index as parameter
- * Compute finger_identity to which we want to setup the trail
- * @return finger_identity
- */
-static uint64_t
-compute_finger_identity_value ()
-{
- uint64_t my_id64;
-
- memcpy (&my_id64, &my_identity, sizeof (uint64_t));
- my_id64 = GNUNET_ntohll (my_id64);
- return (my_id64 + (unsigned long) pow (2, current_search_finger_index));
-}
-
-
-/**
- * Compute immediate predecessor identity in the network.
- * @return peer identity of immediate predecessor.
+ * Compute 64 bit value of finger_identity corresponding to a finger index using
+ * chord formula.
+ * For all fingers:
+ * n.finger[i] = n + pow (2,i),
+ * For predecessor
+ * n.finger[i] = n - 1, where
+ * n = my_identity
+ * i = finger_index.
+ * n.finger[i] = 64 bit finger value
+ * @param finger_index Index corresponding to which we calculate 64 bit value.
+ * @return 64 bit value.
*/
static uint64_t
-compute_predecessor_identity_value ()
+compute_finger_identity_value (unsigned int finger_index)
{
uint64_t my_id64;
memcpy (&my_id64, &my_identity, sizeof (uint64_t));
my_id64 = GNUNET_ntohll (my_id64);
- return (my_id64 -1);
+
+ /* Are we looking for immediate predecessor? */
+ if (PREDECESSOR_FINGER_ID == finger_index)
+ return (my_id64 -1);
+ else
+ return (my_id64 + (unsigned long) pow (2, finger_index));
}
/*
- * Choose a random friend and start looking for the trail to reach to
- * finger identity through this random friend.
+ * Choose a random friend. Start looking for the trail to reach to
+ * finger identity corresponding to current_search_finger_index through
+ * this random friend.
*
* @param cls closure for this task
* @param tc the context under which the task is running
unsigned int is_predecessor;
uint64_t finger_id_value;
+ /* Schedule another send_find_finger_trail_message task. */
next_send_time.rel_value_us =
DHT_FIND_FINGER_TRAIL_INTERVAL.rel_value_us +
GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK,
GNUNET_SCHEDULER_add_delayed (next_send_time, &send_find_finger_trail_message,
NULL);
+ /* My own routing table is all full. I can not store any more trails for which
+ I am source. */
+ if (GNUNET_YES == GDS_ROUTING_threshold_reached())
+ return;
+
target_friend = select_random_friend ();
if (NULL == target_friend)
{
return;
}
-
+
+ finger_id_value = compute_finger_identity_value (current_search_finger_index);
if (PREDECESSOR_FINGER_ID == current_search_finger_index)
- {
- finger_id_value = compute_predecessor_identity_value();
- is_predecessor = 0;
- }
- else
- {
- finger_id_value = compute_finger_identity_value();
is_predecessor = 1;
- }
+ else
+ is_predecessor = 0;
+ /* Generate a unique trail id for trail we are trying to setup. */
GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_STRONG,
&trail_id, sizeof (trail_id));
GDS_NEIGHBOURS_send_trail_setup (my_identity, finger_id_value,
/* Send trail teardown message across the replaced trail. */
struct Trail *replace_trail = &existing_finger->trail_list[largest_trail_index];
- struct FriendInfo *target_friend =
- GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &replace_trail->trail_head->peer);
-
- GDS_NEIGHBOURS_send_trail_teardown (my_identity,
- existing_finger->finger_identity,
- replace_trail->trail_id,
- GDS_ROUTING_SRC_TO_DEST, target_friend);
+
+ GDS_NEIGHBOURS_send_trail_teardown (replace_trail->trail_id,
+ GDS_ROUTING_SRC_TO_DEST,
+ &replace_trail->trail_head->peer);
/* Free the trail. */
while (NULL != (trail_element = replace_trail->trail_head))
{
GNUNET_CONTAINER_DLL_remove (replace_trail->trail_head,
replace_trail->trail_tail, trail_element);
- GNUNET_free (trail_element);
+ GNUNET_free_non_null (trail_element);
}
/* Add new trial at that location. */
/**
- * Send trail teardown message on all trails associated with finger.
- * @param finger_to_be_removed
+ * Send trail teardown message for a specific trail of a finger.
+ * @param finger Finger whose trail is to be removed.
+ * @param trail List of peers in trail from me to a finger, NOT including
+ * endpoints.
*/
static void
-send_trail_teardown (struct FingerInfo *finger)
+send_trail_teardown (struct FingerInfo *finger,
+ struct Trail *trail)
{
- struct Trail *trail_list_iterator;
- struct FriendInfo *target_friend;
- int i;
+ /* FIXME: Now source also stores a trail entry in its routing table. before
+ sending the trail teardown, you should get next_hop from routing table.
+ If it is NULL, it means that path is broken, then remove the trail.
+ return a value to calling function so that if all trails are removed,
+ then remove finger. */
+ /* We should decerement the friend trail count here. */
+ struct FriendInfo *friend;
+
+ GNUNET_assert (NULL != (friend =
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &trail->trail_head->peer)));
+
+ friend->trails_count--;
+ GDS_NEIGHBOURS_send_trail_teardown (trail->trail_id,
+ GDS_ROUTING_SRC_TO_DEST,
+ &trail->trail_head->peer);
+}
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity, &my_identity)
- || (NULL != GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &finger->finger_identity)))
- return;
+
+/**
+ * Send trail teardown message across all the trails to reach to finger.
+ * @param finger Finger whose all the trail should be freed.
+ */
+static void
+send_all_finger_trails_teardown (struct FingerInfo *finger)
+{
+ struct Trail *trail;
+ int i;
for (i = 0; i < finger->trails_count; i++)
{
- trail_list_iterator = &finger->trail_list[i];
- if (trail_list_iterator->trail_length > 0)
+ trail = &finger->trail_list[i];
+ if (trail->trail_length > 0)
{
- target_friend =
- GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &trail_list_iterator->trail_head->peer);
- // check target_friend
- GDS_NEIGHBOURS_send_trail_teardown (my_identity, finger->finger_identity,
- trail_list_iterator->trail_id,
- GDS_ROUTING_SRC_TO_DEST,
- target_friend);
+ /* decerement the friend trails count. */
+ send_trail_teardown (finger, trail);
}
}
}
/**
- * Decrement the trail count of the first friend to reach the finger
- * In case finger is the friend, then decrement its trail count.
- * @param finger
+ * Free a specific trail
+ * @param trail List of peers to be freed.
*/
static void
-decrement_friend_trail_count (struct FingerInfo *finger)
+free_trail (struct Trail *trail)
{
- struct Trail *trail_list_iterator;
- struct FriendInfo *target_friend;
- int i = 0;
-
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
- &my_identity))
- return;
+ struct Trail_Element *trail_element;
- for (i = 0; i < finger->trails_count; i++)
+ while (NULL != (trail_element = trail->trail_head))
{
- trail_list_iterator = &finger->trail_list[i];
- if (trail_list_iterator->trail_length > 0)
- target_friend =
- GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &trail_list_iterator->trail_head->peer);
- else
- target_friend =
- GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &finger->finger_identity);
-
- // check target_friend for NULL
- /* FIXME: we have removed first_friend_trail_count field. */
- target_friend->trails_count--;
- //trail_list_iterator->first_friend_trail_count--;
- }
- return;
+ GNUNET_CONTAINER_DLL_remove (trail->trail_head,
+ trail->trail_tail,
+ trail_element);
+ GNUNET_free_non_null (trail_element);
+ }
+ trail->trail_head = NULL;
+ trail->trail_tail = NULL;
}
* @param finger Finger to be freed.
*/
static void
-free_finger (struct FingerInfo *finger)
+free_finger (struct FingerInfo *finger, unsigned int finger_table_index)
{
- struct Trail *trail_list_iterator;
- struct Trail_Element *trail_element;
+ struct Trail *trail;
unsigned int i;
for (i = 0; i < finger->trails_count; i++)
{
- trail_list_iterator = &finger->trail_list[i];
- while (NULL != (trail_element = trail_list_iterator->trail_head))
- {
- GNUNET_CONTAINER_DLL_remove (trail_list_iterator->trail_head,
- trail_list_iterator->trail_tail,
- trail_element);
- GNUNET_free (trail_element);
- }
+ trail = &finger->trail_list[i];
+ if (GNUNET_NO == trail->is_present)
+ continue;
+
+ if (trail->trail_length > 0)
+ free_trail (trail);
}
- GNUNET_free (finger);
+
+ finger->is_present = GNUNET_NO;
+ memset ((void *)&finger_table[finger_table_index], 0, sizeof (finger_table[finger_table_index]));
}
/**
- * Add a new entry in finger hashmap at finger_map_index
+ * FIXME: ensure that you are not adding any trail to reach to a friend which
+ * is a finger. Also decide on should you increment trails count of a friend
+ * which is also a finger.
+ * Add a new entry in finger table at finger_table_index.
+ * In case finger identity is me or a friend, then don't add a trail. NOTE
+ * trail length to reach to a finger can be 0 only if the finger is a friend
+ * or my identity.
+ * In case a finger is a friend, then increment the trails count of the friend.
* @param finger_identity Peer Identity of new finger
* @param finger_trail Trail to reach from me to finger (excluding both end points).
* @param finger_trail_length Total number of peers in @a finger_trail.
* @param trail_id Unique identifier of the trail.
- * @param finger_map_index Index in finger hashmap.
- * @return #GNUNET_OK if new entry is added
- * #GNUNET_NO -- FIXME: need to check what value does hahsmap put
- * returns on failure.
+ * @param finger_table_index Index in finger table.
*/
-static int
-add_new_entry (struct GNUNET_PeerIdentity finger_identity,
- const struct GNUNET_PeerIdentity *finger_trail,
- unsigned int finger_trail_length,
- struct GNUNET_HashCode trail_id,
- unsigned int finger_map_index)
+static void
+add_new_finger (struct GNUNET_PeerIdentity finger_identity,
+ const struct GNUNET_PeerIdentity *finger_trail,
+ unsigned int finger_trail_length,
+ struct GNUNET_HashCode trail_id,
+ unsigned int finger_table_index)
{
struct FingerInfo *new_entry;
struct FriendInfo *first_trail_hop;
- struct Trail *first_trail;
+ struct Trail *trail;
int i = 0;
-
+
new_entry = GNUNET_new (struct FingerInfo);
new_entry->finger_identity = finger_identity;
- new_entry->finger_map_index = finger_map_index;
+ new_entry->finger_table_index = finger_table_index;
+ new_entry->is_present = GNUNET_YES;
+
+ /* If the new entry is my own identity or a friend. */
+ if ((0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &finger_identity)) ||
+ (NULL != GNUNET_CONTAINER_multipeermap_get (friend_peermap, &finger_identity)))
+ {
+ new_entry->trails_count = 0;
+ finger_table[finger_table_index] = *new_entry;
+ return;
+ }
+
+ /* finger trail length can be 0 only in case if finger is my identity or
+ finger is friend. We should never reach here. */
+ GNUNET_assert (finger_trail_length > 0);
+
+ GNUNET_assert (NULL !=
+ (first_trail_hop =
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &finger_trail[0])));
new_entry->trails_count = 1;
-
- if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &finger_identity))
+ first_trail_hop->trails_count++;
+
+ /* Copy the finger trail into trail. */
+ trail = GNUNET_new (struct Trail);
+ while (i < finger_trail_length)
{
- if (finger_trail_length > 0)
- {
- first_trail_hop = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &finger_trail[0]);
- }
- else
- {
- first_trail_hop = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &finger_identity);
- }
-
- first_trail_hop->trails_count++;
- first_trail = &new_entry->trail_list[0];
- /* FIXME: We have removed this field. */
- //first_trail->first_friend_trail_count = first_trail_hop->trails_count;
+ struct Trail_Element *element = GNUNET_new (struct Trail_Element);
- while (i < finger_trail_length)
- {
- struct Trail_Element *element = GNUNET_new (struct Trail_Element);
-
- element->next = NULL;
- element->prev = NULL;
- element->peer = finger_trail[i];
- GNUNET_CONTAINER_DLL_insert_tail (first_trail->trail_head,
- first_trail->trail_tail,
- element);
- i++;
- }
+ element->next = NULL;
+ element->prev = NULL;
+ element->peer = finger_trail[i];
+ GNUNET_CONTAINER_DLL_insert_tail (trail->trail_head,
+ trail->trail_tail,
+ element);
+ i++;
}
-
- return GNUNET_CONTAINER_multihashmap32_put (finger_hashmap,
- new_entry->finger_map_index,
- new_entry,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
+
+ /* Add trail to trail list. */
+ new_entry->trail_list[0].trail_head = trail->trail_head;
+ new_entry->trail_list[0].trail_tail = trail->trail_tail;
+ new_entry->trail_list[0].trail_length = finger_trail_length;
+ new_entry->trail_list[0].trail_id = trail_id;
+ new_entry->trail_list[0].is_present = GNUNET_YES;
+ finger_table[finger_table_index] = *new_entry;
+ return;
}
struct GNUNET_PeerIdentity *new_trail;
int i;
+ /* If I am my own finger identity, then we set trail_length = 0.
+ Note: Here we don't send trail compression message, as no peer in its
+ trail added an entry in its routing table.*/
if (0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &finger_identity))
{
*new_trail_length = 0;
return NULL;
}
+ /* If finger identity is a friend. */
if (NULL != GNUNET_CONTAINER_multipeermap_get (friend_peermap, &finger_identity))
{
+ *new_trail_length = 0;
+
+ /* If there is trail to reach this finger/friend */
if (trail_length > 0)
{
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &trail[0]);
- GDS_NEIGHBOURS_send_trail_compression (my_identity, finger_identity,
+ &trail[0]);
+ /* FIXME: In case its finger == friend, then may be we send a trail
+ teardown message as it does not make any sense to have any routing e
+ entry in your own routing table.*/
+ GDS_NEIGHBOURS_send_trail_compression (my_identity,
trail_id, finger_identity,
target_friend);
- *new_trail_length = 0;
}
return NULL;
}
+ /* For other cases, when its neither a friend nor my own identity.*/
for (i = trail_length - 1; i > 0; i--)
{
+ /* If the element at this index in trail is a friend. */
if (NULL != GNUNET_CONTAINER_multipeermap_get (friend_peermap, &trail[i]))
{
struct FriendInfo *target_friend;
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
&trail[0]);
- GDS_NEIGHBOURS_send_trail_compression (my_identity, finger_identity,
+ GDS_NEIGHBOURS_send_trail_compression (my_identity,
trail_id, trail[i],
target_friend);
- /* Copy the trail from index i to index trail_length -1 and change
- trail length and return */
+ /* Copy the trail from index i to index (trail_length -1) into a new trail
+ * and update new trail length */
new_trail = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity) * i);
while (i < trail_length)
{
i++;
}
*new_trail_length = j+1;
- break;
return new_trail;
}
}
+
+ /* If we found no other friend except the first hop, return the original
+ trail back.*/
+ new_trail = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity) * trail_length);
*new_trail_length = trail_length;
- memcpy (new_trail, new_trail, trail_length * sizeof (struct GNUNET_PeerIdentity));
+ memcpy (new_trail, trail, trail_length * sizeof (struct GNUNET_PeerIdentity));
return new_trail;
}
/**
- * FIXME: Ensure that we add trail in succession in the trail list.
- * There are no free spots within the trail list.
- * Send verify successor message to your successor on all trails to reach
- * the successor.
- * @param successor My current successor
+ * Send verify successor message to your current successor over the shortest
+ * trail.
+ * @param successor Current successor.
*/
static void
send_verify_successor_message (struct FingerInfo *successor)
{
- struct Trail *trail_list_iterator;
- struct GNUNET_HashCode trail_id;
- struct GNUNET_PeerIdentity next_hop;
+ /*
+ * FIXME: should we send a verify successor message across all the trails
+ * in case we send through all friends. It complicates the logic, don't
+ * do it at the moment. Write it as optimization and do it later.
+ * 1. Here we can have 3 types of fingers
+ * --> my own identity
+ * Assumption that the calling function will not send request for
+ * such successor. Move the logic here.
+ * --> friend is a finger
+ * Need to verify if we keep the trails count for a friend. In case of
+ * friend there is no trail to reach to that friend, so
+ * 1. no entry in routing table
+ * 2. no trail id
+ * 3. no trails count
+ * 4. but do we increment the count of trails through the friend?
+ * Trails count is used only to keep a limit on number of trails
+ * that a friend should be part of. No need to increment the trails
+ * count for a friend which is a finegr also. so, if finger = friend
+ * then don't increment the trails count. But if the same friend
+ * is the first friend to reach to some other finger then increment
+ * the trails count. Not sure if this design is correct need to verify
+ * again.
+ * --> real finger
+ */
struct FriendInfo *target_friend;
- struct GNUNET_PeerIdentity *trail;
- unsigned int trail_length;
+ struct GNUNET_HashCode trail_id;
int i;
- int j;
-
+
+ /* If successor is a friend. */
+ if (successor->trails_count == 0)
+ {
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &successor->finger_identity);
+ memset ((void *)&trail_id, 0 , sizeof (trail_id));
+ GDS_NEIGHBOURS_send_verify_successor_message (my_identity,
+ successor->finger_identity,
+ trail_id, NULL, 0,
+ target_friend);
+ return;
+ }
+
for (i = 0; i < successor->trails_count; i++)
{
- trail_list_iterator = &successor->trail_list[i];
- GNUNET_assert (NULL != trail_list_iterator->trail_head);
-
- if (trail_list_iterator->trail_length > 0)
- {
- struct Trail_Element *element;
-
- trail_length = trail_list_iterator->trail_length;
- trail = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity)
- * trail_length);
- element = trail_list_iterator->trail_head;
- for (j = 0; j < trail_length; j++, element = element->next)
- trail[j] = element->peer;
- next_hop = trail_list_iterator->trail_head->peer;
- }
- else
+ struct Trail *trail;
+ struct Trail_Element *element;
+ unsigned int trail_length;
+ int j;
+
+ trail = &successor->trail_list[i];
+
+ /* No trail stored at this index. */
+ if (GNUNET_YES == trail->is_present)
+ continue;
+
+ /* Only in case of a friend we can have no trail. We have already handled
+ * that case. So, now we should never have any such trail. */
+ GNUNET_assert (trail->trail_length > 0);
+ trail_id = trail->trail_id;
+ trail_length = trail->trail_length;
+
+ /* Copy the trail into peer list. */
+ element = trail->trail_head;
+ struct GNUNET_PeerIdentity peer_list[trail_length];
+ while (j < trail_length)
{
- trail = NULL;
- trail_length = 0;
- next_hop = successor->finger_identity;
+ peer_list[j] = element->peer;
+ element = element->next;
+ j++;
}
- trail_id = trail_list_iterator->trail_id;
+
GNUNET_assert (NULL != (target_friend =
- GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop)));
-
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &peer_list[0])));
GDS_NEIGHBOURS_send_verify_successor_message (my_identity,
successor->finger_identity,
- trail_id, trail, trail_length,
+ trail_id, peer_list, trail_length,
target_friend);
- GNUNET_free_non_null (trail);
+
}
}
/**
- * FIXME: Is it safe to assume that current_search_finger_index == finger_map_index?
+ * FIXME" clear abstraction of current search finger index and finger map index.
+ * it never goes to 63. I don't know why
* Update the current search finger index.
*/
static void
-update_current_search_finger_index (struct GNUNET_PeerIdentity new_finger_identity)
+update_current_search_finger_index (struct GNUNET_PeerIdentity finger_identity,
+ unsigned int finger_table_index)
{
struct FingerInfo *successor;
+
+ if (finger_table_index != current_search_finger_index)
+ return;
- successor = GNUNET_CONTAINER_multihashmap32_get (finger_hashmap, 0);
-
+ successor = &finger_table[0];
+ if (GNUNET_NO == successor->is_present)
+ GNUNET_break(0);
+
+ /* We were looking for immediate successor. */
if (0 == current_search_finger_index)
{
+ /* Start looking for immediate predecessor. */
current_search_finger_index = PREDECESSOR_FINGER_ID;
- if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &new_finger_identity))
+ /* If I am not my own successor, then send a verify successor message. */
+ if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &finger_identity))
{
- send_verify_successor_message (successor);
+ send_verify_successor_message (successor);
}
+ return;
}
- else if (0 == GNUNET_CRYPTO_cmp_peer_identity (&new_finger_identity,
- &(successor->finger_identity)))
- {
- current_search_finger_index = 0;
- }
- else
- current_search_finger_index = current_search_finger_index - 1;
+
+ current_search_finger_index = current_search_finger_index - 1;
+ return;
}
+
/**
- * FIXME: Is it sage to assume that finger_map_index == current_search_finger_index
- * Calculate finger_map_index from initial value that we send in trail setup
- * message.
+ * Calculate finger_table_index from initial 64 bit finger identity value that
+ * we send in trail setup message.
* @param ultimate_destination_finger_value Value that we calculated from our
- * identity and finger_map_index.
- * @param is_predecessor Is the entry for predecessor or not.
- * @return finger_map_index which is a value between 0 <= finger_map_index <= 64
- * -1, if no valid finger_map_index is found.
+ * identity and finger_table_index.
+ * @param is_predecessor Is the entry for predecessor or not?
+ * @return finger_table_index Value between 0 <= finger_table_index <= 64
+ * -1, if no valid finger_table_index is found.
*/
-static int
-get_finger_map_index (uint64_t ultimate_destination_finger_value,
- unsigned int is_predecessor)
+static unsigned int
+get_finger_table_index (uint64_t ultimate_destination_finger_value,
+ unsigned int is_predecessor)
{
uint64_t my_id64;
- unsigned int finger_map_index;
-
- finger_map_index = -1;
+ int diff;
+ unsigned int finger_table_index;
+
memcpy (&my_id64, &my_identity, sizeof (uint64_t));
+ my_id64 = GNUNET_ntohll (my_id64);
- if (is_predecessor)
+ /* Is this a predecessor finger? */
+ if (1 == is_predecessor)
{
- if(1 == (my_id64 - ultimate_destination_finger_value))
- finger_map_index = PREDECESSOR_FINGER_ID;
+ diff = my_id64 - ultimate_destination_finger_value;
+ if (1 == diff)
+ finger_table_index = PREDECESSOR_FINGER_ID;
+ else
+ finger_table_index = PREDECESSOR_FINGER_ID + 1; //error value
+
}
- else
+ else
+ {
+ diff = ultimate_destination_finger_value - my_id64;
+ finger_table_index = (log10 (diff))/(log10 (2));
+ }
+
+ return finger_table_index;
+}
+
+
+/**
+ * Remove finger and its associated data structures from finger table.
+ * @param finger Finger to be removed.
+ */
+static void
+remove_existing_finger (struct FingerInfo *existing_finger, unsigned int finger_table_index)
+{
+ struct FriendInfo *friend;
+ struct FingerInfo *finger;
+
+ finger = &finger_table[finger_table_index];
+ GNUNET_assert (GNUNET_YES == finger->is_present);
+
+ /* If I am my own finger, then we have no trails. */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
+ &my_identity))
{
- finger_map_index = log (ultimate_destination_finger_value - my_id64);
+ finger->is_present = GNUNET_NO;
+ memset ((void *)&finger_table[finger_table_index], 0, sizeof (finger_table[finger_table_index]));
+ return;
}
- if ((finger_map_index > PREDECESSOR_FINGER_ID) ||
- (finger_map_index == current_search_finger_index))
- finger_map_index = -1;
+ /* If finger is a friend, then decrement the trail count and free the finger. */
+ friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &finger->finger_identity);
+ if (NULL != friend)
+ {
+ friend->trails_count--;
+ finger->is_present = GNUNET_NO;
+ memset ((void *)&finger_table[finger_table_index], 0, sizeof (finger_table[finger_table_index]));
+ return;
+ }
+
+ /* For all other fingers, send trail teardown across all the trails to reach
+ finger, and free the finger. */
+ send_all_finger_trails_teardown (finger);
+ free_finger (finger, finger_table_index);
+ return;
+}
+
+#if 0
+/**
+ * This is a test function to print all the entries of friend table.
+ */
+static void
+test_friend_peermap_print ()
+{
+ struct FriendInfo *friend;
+ struct GNUNET_CONTAINER_MultiPeerMapIterator *friend_iter;
+ struct GNUNET_PeerIdentity print_peer;
+ struct GNUNET_PeerIdentity key_ret;
+ int i;
+
+ friend_iter = GNUNET_CONTAINER_multipeermap_iterator_create (friend_peermap);
- return finger_map_index;
+ for (i = 0; i < GNUNET_CONTAINER_multipeermap_size (friend_peermap); i++)
+ {
+ if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next (friend_iter,
+ &key_ret,
+ (const void **)&friend))
+ {
+ memcpy (&print_peer, &key_ret, sizeof (struct GNUNET_PeerIdentity));
+ FPRINTF (stderr,_("\nSUPU %s, %s, %d, friend = %s, friend->trails_count = %d"),
+ __FILE__, __func__,__LINE__, GNUNET_i2s(&print_peer), friend->trails_count);
+ }
+ }
}
/**
- * Check if there is already an entry in finger peermap for given finger map index.
- * If yes, then select the closest finger. If new and existing finger are same,
- * the check if you can store more trails. If yes then add trail, else keep the best
- * trails to reach to the finger. If the new finger is closest, add it.
- * Then, update current_search_finger_index.
- * @param new_finger_identity Peer Identity of new finger
- * @param new_finger_trail Trail to reach the new finger
- * @param new_finger_length Total number of peers in @a new_finger_trail.
- * @param is_predecessor Is this entry for predecessor in finger_peermap.
- * @param new_finger_trail_id Unique identifier of @new_finger_trail.
- * @return #GNUNET_YES if the new entry is added
- * #GNUNET_NO if new entry is not added, either it was discarded or
- * it was same as existing finger at finger map index.
+ * This is a test function, to print all the entries of finger table.
*/
-static int
+static void
+test_finger_table_print()
+{
+ struct FingerInfo *finger;
+ struct GNUNET_PeerIdentity print_peer;
+ struct Trail *trail;
+ int i;
+ int j;
+ int k;
+
+ FPRINTF (stderr,_("\nSUPU************ FINGER_TABLE"));
+ for (i = 0; i < MAX_FINGERS; i++)
+ {
+ finger = &finger_table[i];
+
+ if (GNUNET_NO == finger->is_present)
+ continue;
+
+ print_peer = finger->finger_identity;
+ FPRINTF (stderr,_("\nSUPU %s, %s, %d, finger_table[%d] = %s, trails_count = %d"),
+ __FILE__, __func__,__LINE__,i,GNUNET_i2s (&print_peer), finger->trails_count);
+
+
+ for (j = 0; j < finger->trails_count; j++)
+ {
+ trail = &finger->trail_list[j];
+ FPRINTF (stderr,_("\nSUPU %s, %s, %d, trail_id[%d]=%s"),__FILE__, __func__,__LINE__,j, GNUNET_h2s(&trail->trail_id));
+ struct Trail_Element *element;
+ element = trail->trail_head;
+ for (k = 0; k < trail->trail_length; k++)
+ {
+ print_peer = element->peer;
+ FPRINTF (stderr,_("\nSUPU %s, %s, %d,trail[%d] = %s "),__FILE__, __func__,__LINE__,k, GNUNET_i2s(&print_peer));
+ element = element->next;
+ }
+ }
+ }
+}
+#endif
+
+/**
+ * Check if there is already an entry in finger_table at finger_table_index.
+ * We get the finger_table_index from 64bit finger value we got from the network.
+ * -- If yes, then select the closest finger.
+ * -- If new and existing finger are same, then check if you can store more
+ * trails.
+ * -- If yes then add trail, else keep the best trails to reach to the
+ * finger.
+ * -- If the new finger is closest, remove the existing entry, send trail
+ * teardown message across all the trails to reach the existing entry.
+ * Add the new finger.
+ * -- If new and existing finger are different, and existing finger is closest
+ * then do nothing.
+ * -- Update current_search_finger_index.
+ * @param finger_identity Peer Identity of new finger
+ * @param finger_trail Trail to reach the new finger
+ * @param finger_length Total number of peers in @a new_finger_trail.
+ * @param is_predecessor Is this entry for predecessor in finger_table?
+ * @param finger_value 64 bit value of finger identity that we got from network.
+ * @param finger_trail_id Unique identifier of @finger_trail.
+ */
+static void
finger_table_add (struct GNUNET_PeerIdentity finger_identity,
const struct GNUNET_PeerIdentity *finger_trail,
unsigned int finger_trail_length,
{
struct FingerInfo *existing_finger;
struct GNUNET_PeerIdentity *closest_peer;
- int updated_finger_trail_length;
struct GNUNET_PeerIdentity *updated_trail;
- unsigned int finger_map_index;
- unsigned int new_entry_added;
-
- new_entry_added = GNUNET_NO;
+ struct FingerInfo *successor;
+ int updated_finger_trail_length;
+ unsigned int finger_table_index;
- finger_map_index = get_finger_map_index (finger_value,
- is_predecessor);
+ //test_friend_peermap_print();
+ //test_finger_table_print();
- if (-1 == finger_map_index)
+ /* Get the finger_table_index corresponding to finger_value we got from network.*/
+ finger_table_index = get_finger_table_index (finger_value, is_predecessor);
+
+ /* Invalid finger_table_index. */
+ if ((finger_table_index > PREDECESSOR_FINGER_ID))
{
GNUNET_break_op (0);
- return GNUNET_SYSERR;
+ return;
}
+ updated_finger_trail_length = finger_trail_length;
updated_trail =
scan_and_compress_trail (finger_identity, finger_trail,
finger_trail_length, finger_trail_id,
&updated_finger_trail_length);
+
+ /* If the new entry is same as successor then don't add it in finger table,
+ reset the current search finger index and exit. */
+ if ((0 != finger_table_index) &&
+ (PREDECESSOR_FINGER_ID != finger_table_index) &&
+ (finger_table_index == current_search_finger_index))
+ {
+ successor = &finger_table[0];
+ GNUNET_assert (GNUNET_YES == successor->is_present);
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger_identity,
+ &successor->finger_identity))
+ {
+ current_search_finger_index = 0;
+ return;
+ }
+ }
- existing_finger = GNUNET_CONTAINER_multihashmap32_get (finger_hashmap,
- finger_map_index);
+ existing_finger = &finger_table[finger_table_index];
- /* No entry present in finger hashmap for given finger map index. */
- if (NULL == existing_finger)
+ /* No entry present in finger_table for given finger map index. */
+ if (GNUNET_NO == existing_finger->is_present)
{
- add_new_entry (finger_identity, updated_trail, updated_finger_trail_length,
- finger_trail_id, finger_map_index);
- update_current_search_finger_index (finger_identity);
- return GNUNET_YES;
+ add_new_finger (finger_identity, updated_trail, updated_finger_trail_length,
+ finger_trail_id, finger_table_index);
+ update_current_search_finger_index (finger_identity, finger_table_index);
+ return;
}
/* If existing entry and finger identity are not same. */
{
closest_peer = select_closest_peer (&existing_finger->finger_identity,
&finger_identity,
- finger_value, finger_map_index);
+ finger_value, finger_table_index);
/* If the new finger is the closest peer. */
if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger_identity, closest_peer))
{
- GNUNET_assert (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity,
- &finger_identity));
-
- send_trail_teardown (existing_finger);
- decrement_friend_trail_count (existing_finger);
- free_finger (existing_finger);
- add_new_entry (finger_identity, updated_trail, updated_finger_trail_length,
- finger_trail_id, finger_map_index);
- new_entry_added = GNUNET_YES;
+ remove_existing_finger (existing_finger, finger_table_index);
+ add_new_finger (finger_identity, updated_trail, updated_finger_trail_length,
+ finger_trail_id, finger_table_index);
}
}
else
/* If both new and existing entry are same as my_identity, then do nothing. */
if (0 == GNUNET_CRYPTO_cmp_peer_identity (&(existing_finger->finger_identity),
&my_identity))
- {
- return GNUNET_NO;
- }
+ return;
/* If the existing finger is not a friend. */
if (NULL ==
GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &(existing_finger->finger_identity)))
+ &existing_finger->finger_identity))
{
+ /* If there is space to store more trails. */
if (existing_finger->trails_count < MAXIMUM_TRAILS_PER_FINGER)
add_new_trail (existing_finger, updated_trail,
finger_trail_length, finger_trail_id);
select_and_replace_trail (existing_finger, updated_trail,
finger_trail_length, finger_trail_id);
}
- new_entry_added = GNUNET_NO;
}
-
- update_current_search_finger_index (finger_identity);
- return new_entry_added;
+ update_current_search_finger_index (finger_identity, finger_table_index);
+ return;
}
}
else
{
- /*FIXME: Here you should use enum GDS_NEIGHBOURS_FINGER_TYPE in place of 0. */
next_hop = find_successor (key_value, &best_known_dest,
&intermediate_trail_id, GDS_FINGER_TYPE_NON_PREDECESSOR);
}
get_length = ntohl (get->get_path_length);
best_known_dest = get->best_known_destination;
intermediate_trail_id = get->intermediate_trail_id;
- if (get_length > 0)
- get_path = (struct GNUNET_PeerIdentity *)&get[1];
+ get_path = (struct GNUNET_PeerIdentity *)&get[1];
if ((msize <
sizeof (struct PeerGetMessage) +
GNUNET_break_op (0);
return GNUNET_YES;
}
-
+
/* Add sender to get path */
struct GNUNET_PeerIdentity gp[get_length + 1];
memcpy (gp, get_path, get_length * sizeof (struct GNUNET_PeerIdentity));
}
else
{
- /*FIXME: Here you should use enum GDS_NEIGHBOURS_FINGER_TYPE in place of 0. */
next_hop = find_successor (key_value, &best_known_dest,
&intermediate_trail_id, GDS_FINGER_TYPE_NON_PREDECESSOR);
}
}
+/**
+ * Get the best known next destination (local_dest) among your fingers, friends
+ * and my identity. If @a current_dest is some other peer and not me, then
+ * compare curent_dest and local_dest.
+ * @param final_dest_finger_value Peer closest to this value will be
+ * @a local_best_known_dest
+ * @param local_best_known_dest[out] Updated to peer identity which is closest to
+ * @a final_dest_finger_value.
+ * @param new_intermediate_trail_id In case @a local_best_known_dest is a finger,
+ * then the trail id to reach to the finger
+ * @param is_predecessor Is source peer trying to setup trail to its predecessor
+ * or not.
+ * @param current_dest Peer which should get this message ultimately according
+ * to the peer which sent me this message. It could be me
+ * or some other peer. In case it is not me, then I am a part
+ * of trail to reach to that peer.
+ * @return
+ */
+static struct GNUNET_PeerIdentity *
+get_local_best_known_next_hop (uint64_t final_dest_finger_value,
+ struct GNUNET_PeerIdentity *local_best_known_dest,
+ struct GNUNET_HashCode *new_intermediate_trail_id,
+ struct GNUNET_HashCode intermediate_trail_id,
+ unsigned int is_predecessor,
+ struct GNUNET_PeerIdentity *current_dest)
+{
+ struct GNUNET_PeerIdentity *next_hop_to_local_best_known_dest;
+
+ /* Choose a local best known hop among your fingers, friends and you. */
+ next_hop_to_local_best_known_dest = find_successor (final_dest_finger_value,
+ local_best_known_dest,
+ new_intermediate_trail_id,
+ is_predecessor);
+
+ /* Are we just a part of a trail towards a finger (current_destination)? */
+ if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&my_identity, current_dest)))
+ {
+ struct GNUNET_PeerIdentity *closest_peer;
+
+ /* Select best successor among one found locally and current_destination
+ * that we got from network.*/
+ closest_peer = select_closest_peer (local_best_known_dest,
+ current_dest,
+ final_dest_finger_value,
+ is_predecessor);
+
+ /* Is current dest (end point of the trail of which I am a part) closest_peer? */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (current_dest, closest_peer))
+ {
+ next_hop_to_local_best_known_dest =
+ GDS_ROUTING_get_next_hop (intermediate_trail_id,
+ GDS_ROUTING_SRC_TO_DEST);
+ /* FIXME: Here we found next_hop NULL from routing table, but we still
+ * have a next_hop from find_successor should we not break and choose that
+ * next_hop. */
+ if (NULL == next_hop_to_local_best_known_dest)
+ {
+ GNUNET_break_op (0);
+ return NULL;
+ }
+
+ local_best_known_dest = current_dest;
+ *new_intermediate_trail_id = intermediate_trail_id;
+ }
+ }
+
+ GNUNET_assert (NULL != next_hop_to_local_best_known_dest);
+ return next_hop_to_local_best_known_dest;
+}
+
+
/* Core handle for PeerTrailSetupMessage.
* @param cls closure
* @param message message
{
const struct PeerTrailSetupMessage *trail_setup;
const struct GNUNET_PeerIdentity *trail_peer_list;
- struct GNUNET_PeerIdentity local_best_known_destination;
- struct GNUNET_PeerIdentity current_destination;
- struct GNUNET_PeerIdentity *next_hop;
+ struct GNUNET_PeerIdentity *local_best_known_dest;
+ struct GNUNET_PeerIdentity current_dest;
+ struct GNUNET_PeerIdentity *next_hop_towards_local_best_known_dest;
struct GNUNET_PeerIdentity next_peer;
struct FriendInfo *target_friend;
struct GNUNET_PeerIdentity source;
- uint64_t ultimate_destination_finger_value;
+ uint64_t final_dest_finger_val;
struct GNUNET_HashCode new_intermediate_trail_id;
struct GNUNET_HashCode intermediate_trail_id;
struct GNUNET_HashCode trail_id;
size_t msize;
msize = ntohs (message->size);
- /* There are PeerId's appended to the end of the message! */
if (msize < sizeof (struct PeerTrailSetupMessage))
{
GNUNET_break_op (0);
}
trail_peer_list = (const struct GNUNET_PeerIdentity *)&trail_setup[1];
- current_destination = trail_setup->best_known_destination;
+ current_dest = trail_setup->best_known_destination;
trail_id = trail_setup->trail_id;
- ultimate_destination_finger_value =
- GNUNET_ntohll (trail_setup->ultimate_destination_finger_value);
+ final_dest_finger_val =
+ GNUNET_ntohll (trail_setup->final_destination_finger_value);
source = trail_setup->source_peer;
is_predecessor = ntohl (trail_setup->is_predecessor);
intermediate_trail_id = trail_setup->intermediate_trail_id;
+ /* Is my routing table full? */
if (GNUNET_YES == GDS_ROUTING_threshold_reached())
{
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer);
- GDS_NEIGHBOURS_send_trail_rejection (source, ultimate_destination_finger_value,
+ GDS_NEIGHBOURS_send_trail_rejection (source, final_dest_finger_val,
my_identity, is_predecessor,
trail_peer_list, trail_length,
trail_id, target_friend,
return GNUNET_OK;
}
+ local_best_known_dest = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
- next_hop = find_successor (ultimate_destination_finger_value,
- &local_best_known_destination,
- &new_intermediate_trail_id, is_predecessor);
-
- /* Are we just a part of a trail towards a finger (current_destination)? */
- if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&my_identity, ¤t_destination)))
+ /* Get the next hop to forward the trail setup request. */
+ next_hop_towards_local_best_known_dest =
+ get_local_best_known_next_hop (final_dest_finger_val,
+ local_best_known_dest,
+ &new_intermediate_trail_id,
+ intermediate_trail_id,
+ is_predecessor,
+ ¤t_dest);
+
+ /* Am I the final destination? */
+ if (0 == (GNUNET_CRYPTO_cmp_peer_identity (local_best_known_dest,
+ &my_identity)))
{
- struct GNUNET_PeerIdentity *closest_peer;
-
- /* Select best successor among one found locally and current_destination.*/
- closest_peer = select_closest_peer (&local_best_known_destination,
- ¤t_destination,
- ultimate_destination_finger_value,
- is_predecessor);
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (¤t_destination,
- closest_peer))
+ /* If I was not the source of this message for which now I am destination */
+ if ((0 != GNUNET_CRYPTO_cmp_peer_identity (&source, &my_identity)) ||
+ (trail_length > 0))
{
- next_hop = GDS_ROUTING_get_next_hop (intermediate_trail_id,
- GDS_ROUTING_SRC_TO_DEST);
- if (NULL == next_hop) /* FIXME: Here we found next_hop NULL from routing table,
- * but we still have a next_hop from find_successor.
- * Should we not break and choose that next_hop. */
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
-
- local_best_known_destination = current_destination;
- new_intermediate_trail_id = intermediate_trail_id;
+ GDS_ROUTING_add (trail_id, *peer, my_identity);
}
- }
-
- GNUNET_assert (NULL != next_hop);
-
- /* Am I the final destination? */
- if (0 == (GNUNET_CRYPTO_cmp_peer_identity (next_hop, &my_identity)))
- {
if (0 == trail_length)
memcpy (&next_peer, &source, sizeof (struct GNUNET_PeerIdentity));
else
my_identity,
target_friend, trail_length,
trail_peer_list,
- ultimate_destination_finger_value,
+ final_dest_finger_val,
is_predecessor, trail_id);
}
else
{
+ /* Add yourself to list of peers. */
struct GNUNET_PeerIdentity peer_list[trail_length + 1];
memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
peer_list[trail_length] = my_identity;
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
+ target_friend =
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ next_hop_towards_local_best_known_dest);
GDS_NEIGHBOURS_send_trail_setup (source,
- ultimate_destination_finger_value,
- local_best_known_destination,
+ final_dest_finger_val,
+ *local_best_known_dest,
target_friend, trail_length + 1, peer_list,
is_predecessor, trail_id,
&new_intermediate_trail_id);
}
+ GNUNET_free (local_best_known_dest);
+ GNUNET_free (next_hop_towards_local_best_known_dest);
return GNUNET_OK;
}
/* FIXME: here we are calculating my_index and comparing also in this function.
And we are doing it again here in this function. Re factor the code. */
/**
+ * FIXME: Should we call this function everywhere in all the handle functions
+ * where we have a trail to verify from or a trail id. something like
+ * if prev hop is not same then drop the message.
* Check if sender_peer and peer from which we should receive the message are
* same or different.
* @param trail_peer_list List of peers in trail
{
int my_index;
+ /* I am the source peer. */
if (0 == (GNUNET_CRYPTO_cmp_peer_identity (&source_peer,
&my_identity)))
{
+ /* Is the first element of the trail is sender_peer.*/
if (trail_length > 0)
{
- // source, then trail_length > 0, trail_peer_list[0] != peer
if (0 != GNUNET_CRYPTO_cmp_peer_identity (&trail_peer_list[0],
sender_peer))
return GNUNET_NO;
}
else
{
- // source, trail_length == 0, finger != peer
+ /* Is finger the sender peer? */
if (0 != GNUNET_CRYPTO_cmp_peer_identity (sender_peer,
&finger_identity))
return GNUNET_NO;
}
else
{
+ /* Get my current location in the trail. */
my_index = search_my_index (trail_peer_list, trail_length);
if (-1 == my_index)
return GNUNET_NO;
- // my_index == trail_length -1, finger != peer
+ /* I am the last element in the trail. */
if ((trail_length - 1) == my_index)
{
+ /* Is finger the sender_peer? */
if (0 != GNUNET_CRYPTO_cmp_peer_identity (sender_peer,
&finger_identity))
return GNUNET_NO;
}
else
{
- // FIXME: if trail_peer_list[my_index + 1] != peer
+ /* Is peer after me in trail the sender peer? */
if (0 != GNUNET_CRYPTO_cmp_peer_identity (sender_peer,
&trail_peer_list[my_index + 1]))
return GNUNET_NO;
/**
+ * FIXME: we should also add a case where we search if we are present in the trail
+ * twice.
* Core handle for p2p trail setup result messages.
* @param closure
* @param message message
trail_peer_list = (const struct GNUNET_PeerIdentity *) &trail_result[1];
ulitmate_destination_finger_value =
GNUNET_ntohll (trail_result->ulitmate_destination_finger_value);
+
/* FIXME: here we are calculating my_index and comparing also in this function.
And we are doing it again here in this function. Re factor the code. */
/* Ensure that sender peer is the peer from which we were expecting the message. */
if (0 == (GNUNET_CRYPTO_cmp_peer_identity (&querying_peer,
&my_identity)))
{
+ /* If I am not my own finger identity, then add routing table entry. */
+ if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &finger_identity))
+ {
+ GDS_ROUTING_add (trail_id, my_identity, *peer);
+ }
+
finger_table_add (finger_identity, trail_peer_list,
trail_length, ulitmate_destination_finger_value,
is_predecessor, trail_id);
return GNUNET_YES;
}
+ /* Get my location in the trail. */
my_index = search_my_index(trail_peer_list, trail_length);
if (-1 == my_index)
{
next_hop = trail_peer_list[my_index - 1];
/* If the querying_peer is its own finger, then don't add an entry in routing
- * table as querying peer will discard the trail.
- */
+ * table as querying peer will discard the trail. */
if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&(trail_result->querying_peer),
&(trail_result->finger_identity))))
{
int i;
int j;
struct GNUNET_PeerIdentity *inverted_trail;
-
+
inverted_trail = GNUNET_malloc (sizeof(struct GNUNET_PeerIdentity) *
trail_length);
i = 0;
/**
- * FIXME:
- * my_current_predecessor != source_peer. get the trail to reach to
- * my_current_predecessor and append it to the trail from source to me.
- * It can contain duplicate elements. Need to get the correct one.
- * In case the source peer of verify successor message is not my successor,
- * then construct a trail from source peer to my current predecessor.
+ * Return the shortest trail to reach from me to my_predecessor.
* @param my_predecessor my current predecessor.
* @param current_trail Trail from source to me.
* @param current_trail_length Total number of peers in @a current_trail
- * @param new_trail_length [out] Total number of peers in updated trail.
+ * @param trail_length [out] Total number of peers in selected trail.
* @return Updated trail from source peer to my_predecessor.
*/
static struct GNUNET_PeerIdentity *
trail_source_to_my_predecessor (const struct GNUNET_PeerIdentity *current_trail,
unsigned int current_trail_length,
- unsigned int *new_trail_length)
+ unsigned int *trail_length)
{
- struct GNUNET_PeerIdentity *new_trail;
- struct Trail *trail_list_iterator;
- struct Trail_Element *trail_iterator;
+ struct GNUNET_PeerIdentity *trail_me_to_predecessor;
+ struct Trail *trail;
+ struct Trail_Element *trail_element;
struct FingerInfo *my_predecessor;
unsigned int i;
- unsigned int j;
unsigned int shortest_trail_length = 0;
unsigned int trail_index = 0;
- my_predecessor = GNUNET_CONTAINER_multihashmap32_get (finger_hashmap,
- PREDECESSOR_FINGER_ID);
-
+ my_predecessor = &finger_table[PREDECESSOR_FINGER_ID];
+
+ GNUNET_assert (GNUNET_YES == my_predecessor->is_present);
+
+ //if my_predecessor is a friend then don't send back any trail. as
+ // there is no trail.
+ *trail_length = 0;
+
+ /* Choose the shortest path from me to my predecessor. */
for (i = 0; i < my_predecessor->trails_count; i++)
{
- trail_list_iterator = &my_predecessor->trail_list[i];
- if (trail_list_iterator->trail_length > shortest_trail_length)
+ trail = &my_predecessor->trail_list[i];
+ if (trail->trail_length > shortest_trail_length)
continue;
- shortest_trail_length = trail_list_iterator->trail_length;
+ shortest_trail_length = trail->trail_length;
trail_index = i;
}
- *new_trail_length = current_trail_length + shortest_trail_length + 1;
- new_trail = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity) *
- *new_trail_length);
- memcpy (new_trail, current_trail,
- current_trail_length * sizeof (struct GNUNET_PeerIdentity));
- new_trail[current_trail_length + 1] = my_identity;
-
+ *trail_length = shortest_trail_length;
+ trail_me_to_predecessor = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity)
+ * *trail_length);
+
+ /* Copy the selected trail and send this trail to calling function. */
i = 0;
- j = current_trail_length + 1;
- trail_list_iterator = &my_predecessor->trail_list[trail_index];
- trail_iterator = trail_list_iterator->trail_head;
+ trail = &my_predecessor->trail_list[trail_index];
+ trail_element = trail->trail_head;
while ( i < shortest_trail_length)
{
- new_trail[j] = trail_iterator->peer;
- j++;
+ trail_me_to_predecessor[i] = trail_element->peer;
i++;
- trail_iterator = trail_iterator->next;
+ trail_element = trail_element->next;
}
- *new_trail_length = j;
- return new_trail;
+ return trail_me_to_predecessor;
}
/**
- * FIMXE: IF you update your predecessor with new finger identity or added
- * a new trail, then you should send add_trail message or else the peers
- * which are part of the trail to reach to your new predecessor will not
- * know its existence.
- * Check if we already have an entry for predecessor in our finger hashmap.
- * If no, then add new predecessor.
- * If yes, then compare new and existing entry. If both are same, and there is
- * place to store more trail, then add entry. If both are different then choose
- * the closest one.
- * @param finger Peer which claims to be our predecessor.
- * @param trail Trail to reach from @a predecessor to me, NOT including both endpoints
- * @param trail_length Total number of peers in @a trail.
- * @return #GNUNET_YES if we added the new entry.
- * #GNUNET_NO, if new entry is not the closest predecessor or both new
- * and existing entry are same.
+ * FIXME In case predecessor is a friend then do we add it in routing table.
+ * if not then check the logic of trail teardown in case we compress the trail
+ * such that friend is finger. then do we remove the entry from end points or
+ * not. Ideally we should remove the entries from end point.
+ * Add finger as your predecessor. To add, first generate a new trail id, invert
+ * the trail to get the trail from me to finger, add an entry in your routing
+ * table, send add trail message to peers which are part of trail from me to
+ * finger and add finger in finger table.
+ * @param finger
+ * @param trail
+ * @param trail_length
*/
-static struct GNUNET_PeerIdentity
-compare_and_update_predecessor (struct GNUNET_PeerIdentity finger_identity,
- const struct GNUNET_PeerIdentity *trail,
+static void
+update_predecessor (struct GNUNET_PeerIdentity finger,
+ struct GNUNET_PeerIdentity *trail,
+ unsigned int trail_length)
+{
+ struct GNUNET_HashCode trail_to_new_predecessor_id;
+ struct GNUNET_PeerIdentity *trail_to_new_predecessor;
+ struct FriendInfo *target_friend;
+
+ /* Generate trail id for trail from me to new predecessor = finger. */
+ GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_STRONG,
+ &trail_to_new_predecessor_id,
+ sizeof (trail_to_new_predecessor_id));
+
+ /* Invert the trail from finger to me to get the trail from me to finger. */
+ if (trail_length == 0)
+ trail_to_new_predecessor = NULL;
+
+ if (trail_length > 0)
+ {
+ trail_to_new_predecessor = invert_trail (trail, trail_length);
+ /* Add an entry in your routing table. */
+ GDS_ROUTING_add (trail_to_new_predecessor_id,
+ trail_to_new_predecessor[trail_length - 1],
+ my_identity);
+
+ target_friend =
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &trail_to_new_predecessor[trail_length - 1]);
+
+ // Before sending the trail may be you need to compress it. And in case
+ // it was a friend how did we got the trail. ??
+
+ /* Add entry in routing table of all peers that are part of trail from me
+ to finger. */
+
+ GDS_NEIGHBOURS_send_add_trail (my_identity,
+ finger,
+ trail_to_new_predecessor_id,
+ trail_to_new_predecessor,
+ trail_length,
+ target_friend);
+ }
+
+ add_new_finger (finger, trail_to_new_predecessor, trail_length,
+ trail_to_new_predecessor_id, PREDECESSOR_FINGER_ID);
+}
+
+
+/* 3. In case you are successor, then
+ * 3.1 check if you have a predecessor
+ * 3.2 if no predecessor, then add the source of this message as your
+ * predecessor. To add, first you should generate a new trail id,
+ * invert the trail, send add trail message across new trail, add
+ * an entry in finger table. Now, destination also have routing
+ * table entry so add in your routing table also.
+ * 3.3 If its closer than existing one, then do everything in step 1 and
+ * free existing finger.
+ * 3.3 If its same as the old one, then do nothing.
+ * 3.4 if its not same as old one, and between source and old one, old one
+ * is the correct predecessor, then construct a trail from source
+ * to your old successor. scan the trail to remove duplicate entries.
+ * 4. send verify successor result, with trail id of trail from source to
+ * me. And also send the new trail from source to reach to its probable
+ * predecessor. */
+ /*
+ * 1. this function is called from both verify and notify.
+ * 2. so write in a way that it is used in both.
+ */
+/**
+ * Check if you have a predecessor.
+ * 1. if no predecessor, then add finger as your predecessor. To add, first
+ * generate a new trail id, invert the trail to get the trail from me to finger,
+ * add an entry in your routing table, send add trail message to peers which
+ * are part of trail from me to finger and add finger in finger table.
+ * 2. If there is a predecessor, then compare existing one and finger.
+ * 2.1 If finger is correct predecessor, then remove current_predecessor. And
+ * do everything in step 1 to add finger into finger table.
+ * 2.2 If current_predecessor is correct predecessor, the construct a trail from
+ * finger to current_predecessor.
+ * @param finger
+ * @param trail
+ * @param trail_length
+ * @return
+ */
+static void
+compare_and_update_predecessor (struct GNUNET_PeerIdentity finger,
+ struct GNUNET_PeerIdentity *trail,
unsigned int trail_length)
{
struct FingerInfo *current_predecessor;
struct GNUNET_PeerIdentity *closest_peer;
- struct GNUNET_PeerIdentity *inverted_trail;
- struct GNUNET_HashCode trail_id;
- uint64_t finger_value;
+ uint64_t predecessor_value;
- current_predecessor = GNUNET_CONTAINER_multihashmap32_get (finger_hashmap,
- PREDECESSOR_FINGER_ID);
- inverted_trail = invert_trail (trail, trail_length);
-
- /* No predecessor in finger table. Add the new predecessor. */
- if (NULL == current_predecessor)
+ current_predecessor = &finger_table[PREDECESSOR_FINGER_ID];
+
+ /* No predecessor. Add finger as your predecessor. */
+ if (GNUNET_NO == current_predecessor->is_present)
{
- add_new_entry (finger_identity, inverted_trail, trail_length,
- trail_id, PREDECESSOR_FINGER_ID);
- return finger_identity;
+ update_predecessor (finger, trail, trail_length);
+ return;
}
- /* If the new predecessor and current predecessor are not same, then choose
- the closest one. */
- if (0 != GNUNET_CRYPTO_cmp_peer_identity (&finger_identity,
- ¤t_predecessor->finger_identity))
- {
- finger_value = compute_predecessor_identity_value();
- closest_peer = select_closest_peer (¤t_predecessor->finger_identity,
- &finger_identity,
- finger_value, PREDECESSOR_FINGER_ID);
-
- /* If the finger is the closest predecessor, then add it in finger table
- * and free resources of current_predecessor. */
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger_identity, closest_peer))
- {
- GNUNET_assert (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity,
- &finger_identity));
-
- send_trail_teardown (current_predecessor);
- decrement_friend_trail_count (current_predecessor);
- free_finger (current_predecessor);
- add_new_entry (finger_identity, inverted_trail, trail_length,
- trail_id, PREDECESSOR_FINGER_ID);
- return finger_identity;
- }
- }
+ predecessor_value = compute_finger_identity_value (PREDECESSOR_FINGER_ID);
+ closest_peer = select_closest_peer (&finger,
+ ¤t_predecessor->finger_identity,
+ predecessor_value, PREDECESSOR_FINGER_ID);
- /* If both finger and current_predecessor are same as my_identity, then do nothing. */
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger_identity, &my_identity))
- return current_predecessor->finger_identity;
-
- /* If the current_predecessor is not a friend. */
- if (NULL ==
- GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- ¤t_predecessor->finger_identity))
+ /* Finger is the closest predecessor. Remove the existing one and add the new
+ one. */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (closest_peer, &finger))
{
- if (current_predecessor->trails_count < MAXIMUM_TRAILS_PER_FINGER)
- add_new_trail (current_predecessor, inverted_trail,
- trail_length, trail_id);
- //FIXME: here you should send add a new trail as you don't have this trail
- // in the routing table.
- else
- select_and_replace_trail (current_predecessor, inverted_trail,
- trail_length, trail_id);
- //FIXME: here you should send add a new trail as you don't have this trail
- // in the routing table.
+ remove_existing_finger (current_predecessor, PREDECESSOR_FINGER_ID);
+ update_predecessor (finger, trail, trail_length);
+ return;
}
- return current_predecessor->finger_identity;
+ return;
}
-/**
+/*
+ * FIXME: if i have no predecessor and I get a new predecessor but the first
+ * friend to reach to that hop is congested then?
+ * 1. check if you are the successor or not.
+ * 2. if not then get the next hop from routing table, and pass the message,
+ * 3. In case you are successor, then
+ * 3.1 check if you have a predecessor
+ * 3.2 if no predecessor, then add the source of this message as your
+ * predecessor. To add, first you should generate a new trail id,
+ * invert the trail, send add trail message across new trail, add
+ * an entry in finger table. Now, destination also have routing
+ * table entry so add in your routing table also.
+ * 3.3 If its closer than existing one, then do everything in step 1 and
+ * free existing finger.
+ * 3.3 If its same as the old one, then do nothing.
+ * 3.4 if its not same as old one, and between source and old one, old one
+ * is the correct predecessor, then choose the shortest path to reach
+ * from you to your predecessor. Pass this trail to source of this message.
+ * It is the responsibility of source peer to scan the trail to reach to
+ * its new probable successor.
+ * 4. send verify successor result, with trail id of trail from source to
+ * me. And also send the trail from me to reach to my predecessor, if
+ * my_predecessor != source.
+ *
* Core handle for p2p verify successor messages.
* @param cls closure
* @param message message
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
static int
-handle_dht_p2p_verify_successor(void *cls, const struct GNUNET_PeerIdentity *peer,
+handle_dht_p2p_verify_successor(void *cls,
+ const struct GNUNET_PeerIdentity *peer,
const struct GNUNET_MessageHeader *message)
{
- struct PeerVerifySuccessorMessage *vsm;
+ const struct PeerVerifySuccessorMessage *vsm;
+ struct GNUNET_HashCode trail_id;
struct GNUNET_PeerIdentity successor;
struct GNUNET_PeerIdentity source_peer;
+ struct GNUNET_PeerIdentity *trail;
struct GNUNET_PeerIdentity *next_hop;
+ struct GNUNET_PeerIdentity *trail_to_predecessor;
+ struct FingerInfo *current_predecessor;
struct FriendInfo *target_friend;
- struct GNUNET_HashCode trail_id;
- struct GNUNET_PeerIdentity current_predecessor;
- struct GNUNET_PeerIdentity *trail;
- struct GNUNET_PeerIdentity *new_trail;
- unsigned int trail_length;
- unsigned int new_trail_length;
+ unsigned int trail_to_predecessor_length;
size_t msize;
-
+ unsigned int trail_length;
+
msize = ntohs (message->size);
- if (msize != sizeof (struct PeerVerifySuccessorMessage))
+
+ /* Here we pass trail to reach from source to successor, and in case successor
+ * does not have any predecessor, then we will add source as my predecessor.
+ * So we pass the trail along with trail id. */
+ if (msize < sizeof (struct PeerVerifySuccessorMessage))
{
GNUNET_break_op (0);
return GNUNET_YES;
}
-
- vsm = (struct PeerVerifySuccessorMessage *) message;
+
+ vsm = (const struct PeerVerifySuccessorMessage *) message;
trail_length = (msize - sizeof (struct PeerVerifySuccessorMessage))/
sizeof (struct GNUNET_PeerIdentity);
if ((msize - sizeof (struct PeerVerifySuccessorMessage)) %
{
GNUNET_break_op (0);
return GNUNET_OK;
- }
+ }
- trail = (struct GNUNET_PeerIdentity *)&vsm[1];
+ trail_id = vsm->trail_id;
source_peer = vsm->source_peer;
successor = vsm->successor;
- trail_id = vsm->trail_id;
-
+ trail = (struct GNUNET_PeerIdentity *)&vsm[1];
+
+ //GDS_ROUTING_test_print(); //FIXME REMOVE AFTERWARDS.
+ //FIXME: we can have a check if peer is correct peer which should have
+ // sent this message. use same function is_sender_peer_correct
+ // but specify direction so that the function can be used in other functions
+ //also.
+
/* I am not the successor of source_peer. Pass the message to next_hop on
* the trail. */
if(0 != (GNUNET_CRYPTO_cmp_peer_identity (&successor, &my_identity)))
return GNUNET_SYSERR;
}
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
+
GDS_NEIGHBOURS_send_verify_successor_message (source_peer, successor,
trail_id, trail, trail_length,
target_friend);
return GNUNET_OK;
}
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer);
- current_predecessor = compare_and_update_predecessor (source_peer,
- trail, trail_length);
- /* source_peer is my current_predecessor. */
- if(0 == (GNUNET_CRYPTO_cmp_peer_identity (¤t_predecessor, &source_peer)))
+ /* I am the destination of this message. */
+
+ /* Check if there is a predecessor or not. */
+ compare_and_update_predecessor (source_peer, trail, trail_length);
+
+ current_predecessor = &finger_table[PREDECESSOR_FINGER_ID];
+ /* Is source of this message my predecessor. */
+ if (0 == (GNUNET_CRYPTO_cmp_peer_identity (¤t_predecessor->finger_identity,
+ &source_peer)))
{
- /* Here we don't need to pass the trail as it is of new use. We can pass
- NULL and trail length = 0. */
- new_trail = NULL;
- new_trail_length = 0;
+ trail_to_predecessor = NULL;
+ trail_to_predecessor_length = 0;
}
else
- {
- new_trail = trail_source_to_my_predecessor (trail, trail_length,
- &new_trail_length);
+ {
+ if (NULL == (GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ ¤t_predecessor->finger_identity)))
+ {
+ /* Only if current predecessor is not a friend, we have a trail to reach
+ to it. Only in that case we pass the trail. */
+ trail_to_predecessor =
+ trail_source_to_my_predecessor (trail, trail_length,
+ &trail_to_predecessor_length);
+ }
+ else
+ {
+ trail_to_predecessor = NULL;
+ trail_to_predecessor_length = 0;
+ }
}
+
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer);
GDS_NEIGHBOURS_send_verify_successor_result (source_peer, my_identity,
- current_predecessor, trail_id,
- new_trail, new_trail_length,
+ current_predecessor->finger_identity,
+ trail_id, trail_to_predecessor,
+ trail_to_predecessor_length,
GDS_ROUTING_DEST_TO_SRC,
target_friend);
return GNUNET_OK;
/**
- * Here you may or may not be the predecessor. If you are then also while adding
- * you have to check and if not then notify new successor. But again the trail
- * may be a problem here.
- * FIXME: I will keep the logic to remove the old trail to reach from me to
- * my old successor here and move adding a new trail from me to new successor to notify
- * new successor. And in case if the new successor also take it as predecessor
- * then call add_trail.
+ * Construct the trail from me to probable successor that goes through current
+ * successor. Scan this trail to check if you can shortcut the trail somehow.
+ * In case we can shortcut the trail, don't send trail compression as we don't
+ * have any entry in routing table.
+ * @param current_successor
+ * @param probable_successor
+ * @param trail_from_curr_to_probable_successor
+ * @param trail_from_curr_to_probable_successor_length
+ * @param trail_to_new_successor_length
+ * @return
+ */
+static struct GNUNET_PeerIdentity *
+get_trail_to_new_successor (struct FingerInfo *current_successor,
+ struct GNUNET_PeerIdentity probable_successor,
+ const struct GNUNET_PeerIdentity *trail,
+ unsigned int trail_length,
+ unsigned int *trail_to_new_successor_length)
+{
+ struct GNUNET_PeerIdentity *trail_to_new_successor;
+
+ /* If the probable successor is a friend, then we don't need to have a trail
+ * to reach to it.*/
+ if (NULL != GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &probable_successor))
+ {
+ trail_to_new_successor = NULL;
+ *trail_to_new_successor_length = 0;
+ return trail_to_new_successor;
+ }
+
+ /*
+ * FIXME: can we some how use the select_finger_trail here??
+ * complete this logic.
+ * 1. Choose the shortest trail to reach to current successor.
+ * 2. append the trail with the current trail
+ * 3. scan the trail for duplicate elements
+ * 4. scan the trail for friend
+ * 5. get the shortest trail.
+ * 6. send back the trail.
+ */
+ return NULL;
+}
+
+
+/**
+ * Compare probable successor and current successor.
+ * If the probable successor is the correct successor, then construct the trail
+ * from me to probable successor that goes through current successor. Scan this
+ * trail to check if you can shortcut the trail somehow. In case we can short
+ * cut the trail, don't send trail compression as we don't have any entry in
+ * routing table.
+ * Once you have scanned trail, then add an entry in finger table.
+ * Add an entry in routing table (Only if new successor is NOT a friend).
+ * @param probable_successor Peer which could be our successor
+ * @param trail_from_curr_to_probable_successor Trail from current successor
+ * to probable successor, NOT
+ * including them.
+ * @param trail_from_curr_to_probable_successor_length Total number of peers
+ * in @a trail_from_curr_to_probable_successor
+ */
+static void
+compare_and_update_successor (struct GNUNET_PeerIdentity probable_successor,
+ const struct GNUNET_PeerIdentity *trail_from_curr_to_probable_successor,
+ unsigned int trail_from_curr_to_probable_successor_length)
+{
+ struct GNUNET_PeerIdentity *closest_peer;
+ struct GNUNET_PeerIdentity *trail_to_new_successor;
+ struct GNUNET_HashCode trail_id;
+ unsigned int trail_to_new_successor_length;
+ uint64_t successor_value;
+ struct FingerInfo *current_successor;
+ struct FriendInfo *target_friend;
+
+ current_successor = &finger_table[0];
+ GNUNET_assert (GNUNET_YES == current_successor->is_present);
+
+ /* Compute the 64 bit value of successor identity. We need this as we need to
+ * find the closest peer w.r.t this value.*/
+ successor_value = compute_finger_identity_value (0);
+ closest_peer = select_closest_peer (¤t_successor->finger_identity,
+ &probable_successor,
+ successor_value, GNUNET_NO);
+
+ /* If the current_successor is the closest one, then exit. */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (closest_peer,
+ ¤t_successor->finger_identity))
+ return;
+
+ /* probable successor is the closest_peer. */
+
+ /* Get the trail to reach to your new successor. */
+ trail_to_new_successor = get_trail_to_new_successor (current_successor,
+ probable_successor,
+ trail_from_curr_to_probable_successor,
+ trail_from_curr_to_probable_successor_length,
+ &trail_to_new_successor_length);
+ /* Remove the existing successor. */
+ remove_existing_finger (current_successor, 0);
+
+ /* Generate a new trail id to reach to your new successor. */
+ GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_STRONG,
+ &trail_id, sizeof (trail_id));
+ add_new_finger (probable_successor, trail_to_new_successor,
+ trail_to_new_successor_length, trail_id, 0);
+
+ /* If probable successor is not a friend, then add an entry in your own
+ routing table. */
+ if (trail_to_new_successor_length > 0)
+ {
+ GDS_ROUTING_add (trail_id, my_identity, trail_to_new_successor[0]);
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &trail_to_new_successor[0]);
+ }
+ else
+ {
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &probable_successor);
+ }
+
+ GDS_NEIGHBOURS_send_notify_new_successor (my_identity, probable_successor,
+ trail_from_curr_to_probable_successor,
+ trail_from_curr_to_probable_successor_length,
+ trail_id,
+ target_friend);
+ return;
+}
+
+
+/*
+ * 1. If you are not the querying peer then pass on the message,
+ * 2. If you are querying peer, then
+ * 2.1 is new successor same as old one
+ * 2.1.1 if yes then do noting
+ * 2.1.2 if no then you need to notify the new one about your existence,
+ * 2.1.2,1 also you need to remove the older successor, remove entry
+ * from finger table, send trail teardown message across all the trail
+ * of older successor. Call notify new successor with new trail id
+ * and new trail to reach it.
* Core handle for p2p verify successor result messages.
* @param cls closure
* @param message message
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
static int
-handle_dht_p2p_verify_successor_result(void *cls, const struct GNUNET_PeerIdentity *peer,
+handle_dht_p2p_verify_successor_result(void *cls,
+ const struct GNUNET_PeerIdentity *peer,
const struct GNUNET_MessageHeader *message)
{
- struct PeerVerifySuccessorResultMessage *vsrm;
+ const struct PeerVerifySuccessorResultMessage *vsrm;
enum GDS_ROUTING_trail_direction trail_direction;
- struct GNUNET_HashCode trail_id;
- unsigned int new_trail_length;
- struct GNUNET_PeerIdentity *new_trail;
struct GNUNET_PeerIdentity querying_peer;
- struct GNUNET_PeerIdentity current_predecessor;
- //struct GNUNET_PeerIdentity old_successor;
+ struct GNUNET_HashCode trail_id;
struct GNUNET_PeerIdentity *next_hop;
struct FriendInfo *target_friend;
+ struct GNUNET_PeerIdentity probable_successor;
+ const struct GNUNET_PeerIdentity *trail;
+ unsigned int trail_length;
size_t msize;
msize = ntohs (message->size);
- if (msize != sizeof (struct PeerVerifySuccessorResultMessage))
+ /* We send a trail to reach from old successor to new successor, if
+ * old_successor != new_successor.*/
+ if (msize < sizeof (struct PeerVerifySuccessorResultMessage))
{
GNUNET_break_op (0);
return GNUNET_YES;
}
- vsrm = (struct PeerVerifySuccessorResultMessage *) message;
- new_trail_length = (msize - sizeof (struct PeerTrailSetupMessage))/
+
+ vsrm = (const struct PeerVerifySuccessorResultMessage *) message;
+ trail_length = (msize - sizeof (struct PeerVerifySuccessorResultMessage))/
sizeof (struct GNUNET_PeerIdentity);
- if ((msize - sizeof (struct PeerTrailSetupMessage)) %
+
+ if ((msize - sizeof (struct PeerVerifySuccessorResultMessage)) %
sizeof (struct GNUNET_PeerIdentity) != 0)
{
GNUNET_break_op (0);
return GNUNET_OK;
- }
+ }
+
+ trail = (const struct GNUNET_PeerIdentity *) &vsrm[1];
+ querying_peer = vsrm->querying_peer;
trail_direction = ntohl (vsrm->trail_direction);
trail_id = vsrm->trail_id;
-
- new_trail = (struct GNUNET_PeerIdentity *) &vsrm[1];
- querying_peer = vsrm->querying_peer;
- current_predecessor = vsrm->current_predecessor;
- //old_successor = vsrm->source_successor;
-
+ probable_successor = vsrm->probable_successor;
+
+ //FIXME: add a check to ensure that peer from which you got the message is
+ //the correct peer.
+ /* I am the querying_peer. */
if(0 == (GNUNET_CRYPTO_cmp_peer_identity (&querying_peer, &my_identity)))
{
-#if 0
- //Here I am the final quering peer and its verify successor result.
- // now I know it is for successor and now I don't have any finger_map_index
- // as parameter in finger_table_add.
- // BIG FIX HOW TO ADAPT IT FOR change in finger_table_add
- struct GNUNET_HashCode new_finger_trail_id;
- /* FIXME: generate a new trail id. */
- if (GNUNET_YES == finger_table_add (my_new_successor,
- new_trail,
- new_trail_length,
- PREDECESSOR_FINGER_ID, new_finger_trail_id))
- {
- if (new_trail_length > 0)
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &new_trail[0]);
- else
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- peer);
- GDS_NEIGHBOURS_send_trail_teardown (my_identity, old_successor, trail_id,
- GDS_ROUTING_SRC_TO_DEST, target_friend);
- GDS_NEIGHBOURS_send_notify_new_successor (my_identity, my_new_successor,
- new_trail,
- new_trail_length,
- new_finger_trail_id, target_friend);
- }
-#endif
+ compare_and_update_successor (probable_successor, trail, trail_length);
return GNUNET_OK;
}
-
+
+ /*If you are not the querying peer then pass on the message */
GNUNET_assert (NULL != (next_hop =
GDS_ROUTING_get_next_hop (trail_id, trail_direction)));
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
GDS_NEIGHBOURS_send_verify_successor_result (querying_peer,
- vsrm->source_successor,
- current_predecessor, trail_id,
- new_trail,
- new_trail_length,
+ vsrm->current_successor,
+ probable_successor, trail_id,
+ trail,
+ trail_length,
trail_direction, target_friend);
return GNUNET_OK;
}
-/*
- * FIXME: here before adding the peer you again have to call to check
- * if its correct predecessor or not.
+/*
+ * Add entry in your routing table if source of the message is not a friend.
+ * Irrespective if destination peer accepts source peer as predecessor or not,
+ * we need to add an entry. So, that in next round to verify successor, source
+ * is able to reach to its successor.
+ * Check if you are the new successor of this message
+ * 1. If yes the call function compare_and_update_successor(). This function
+ * checks if source is real predecessor or not and take action accordingly.
+ * 2. If not then find the next hop to find the message from the trail that
+ * you got from the message and pass on the message.
* Core handle for p2p notify new successor messages.
* @param cls closure
* @param message message
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
static int
-handle_dht_p2p_notify_new_successor(void *cls, const struct GNUNET_PeerIdentity *peer,
+handle_dht_p2p_notify_new_successor(void *cls,
+ const struct GNUNET_PeerIdentity *peer,
const struct GNUNET_MessageHeader *message)
{
- struct PeerNotifyNewSuccessorMessage *nsm;
+ const struct PeerNotifyNewSuccessorMessage *nsm;
struct GNUNET_PeerIdentity *trail;
struct GNUNET_PeerIdentity source;
struct GNUNET_PeerIdentity new_successor;
- struct FriendInfo *target_friend;
- struct GNUNET_PeerIdentity closest_successor;
struct GNUNET_HashCode trail_id;
- unsigned int my_index;
struct GNUNET_PeerIdentity next_hop;
+ struct FriendInfo *target_friend;
+ int my_index;
size_t msize;
uint32_t trail_length;
msize = ntohs (message->size);
- if (msize != sizeof (struct PeerNotifyNewSuccessorMessage))
+ /* We have the trail to reach from source to new successor. */
+ if (msize < sizeof (struct PeerNotifyNewSuccessorMessage))
{
GNUNET_break_op (0);
return GNUNET_YES;
}
- nsm = (struct PeerNotifyNewSuccessorMessage *) message;
+ nsm = (const struct PeerNotifyNewSuccessorMessage *) message;
trail_length = (msize - sizeof (struct PeerNotifyNewSuccessorMessage))/
sizeof (struct GNUNET_PeerIdentity);
if ((msize - sizeof (struct PeerTrailRejectionMessage)) %
{
GNUNET_break_op (0);
return GNUNET_OK;
- }
-
- if ((msize < sizeof (struct PeerNotifyNewSuccessorMessage) +
- trail_length * sizeof (struct GNUNET_PeerIdentity)) ||
- (trail_length >
- GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
- {
- GNUNET_break_op (0);
- return GNUNET_YES;
}
-
+
trail = (struct GNUNET_PeerIdentity *) &nsm[1];
source = nsm->source_peer;
new_successor = nsm->new_successor;
- trail_id = nsm->trail_id;
-
+ trail_id = nsm->trail_id;
+
+ //FIXME: add a check to make sure peer is correct.
+
/* I am the new_successor to source_peer. */
if ( 0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &new_successor))
{
- closest_successor = compare_and_update_predecessor (source, trail, trail_length);
- /* If the source peer is my new predecessor, then add trail in the
- routing table of all the peers which are part of the trail to reach from
- me to source, NOT including endpoints.
- FIXME: In case we have same predecessor but we added just a new trail, then
- we are not sending add a new trail message. Need to update this. */
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&closest_successor, &source))
+ /* Add an entry in routing table only if new predecessor is not a friend. */
+ if (NULL == GNUNET_CONTAINER_multipeermap_get(friend_peermap, &source))
{
- struct GNUNET_HashCode new_trail_id;
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- peer);
- GDS_NEIGHBOURS_send_add_trail (my_identity, source, new_trail_id,
- trail, trail_length, target_friend);
+ GDS_ROUTING_add (trail_id, *peer, my_identity);
}
+ compare_and_update_predecessor (source, trail, trail_length);
return GNUNET_OK;
}
-
+
+ /* I am part of trail to reach to successor. */
my_index = search_my_index (trail, trail_length);
if (-1 == my_index)
{
next_hop = new_successor;
else
next_hop = trail[my_index + 1];
+
+ /* Add an entry in routing table for trail from source to its new successor. */
GNUNET_assert (GNUNET_OK == GDS_ROUTING_add (trail_id, *peer, next_hop));
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
GDS_NEIGHBOURS_send_notify_new_successor (source, new_successor, trail,
trail_length,
trail_id, target_friend);
return GNUNET_OK;
+
}
/**
- * FIXME: Here you should keep the trail id with you.
+ * 1. Set the congestion timeout for the friend which is congested and sent
+ * you this message.
+ * 2. Check if you were the source of this message
+ * 2.1 If yes then exit. find_finger_trail_task is scheduled periodically.
+ * So, we will eventually send a new request to setup trail to finger.
+ * 2. Check if you can handle more trails through you. (Routing table space)
+ * 2.1 If not then you are congested. Set your congestion time and pass this
+ * message to peer before you in the trail setup so far.
+ * 2.2 If yes, the call find_successor(). It will give you the next hop to
+ * pass this message.
+ * 2.2.1 If you are the final destination, then send back the trail setup
+ * result.
+ * 2.2.2 If you are not the final dest, then send trail setup message to
+ * next_hop.
* Core handler for P2P trail rejection message
* @param cls closure
* @param message message
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
static int
-handle_dht_p2p_trail_rejection(void *cls, const struct GNUNET_PeerIdentity *peer,
- const struct GNUNET_MessageHeader *message)
+handle_dht_p2p_trail_setup_rejection (void *cls,
+ const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message)
{
- struct PeerTrailRejectionMessage *trail_rejection;
+ const struct PeerTrailRejectionMessage *trail_rejection;
unsigned int trail_length;
- struct GNUNET_PeerIdentity *trail_peer_list;
+ const struct GNUNET_PeerIdentity *trail_peer_list;
struct FriendInfo *target_friend;
struct GNUNET_TIME_Relative congestion_timeout;
struct GNUNET_HashCode trail_id;
size_t msize;
msize = ntohs (message->size);
- if (msize != sizeof (struct PeerTrailRejectionMessage))
+ /* We are passing the trail setup so far. */
+ if (msize < sizeof (struct PeerTrailRejectionMessage))
{
GNUNET_break_op (0);
return GNUNET_YES;
}
- trail_rejection = (struct PeerTrailRejectionMessage *) message;
+ trail_rejection = (const struct PeerTrailRejectionMessage *) message;
trail_length = (msize - sizeof (struct PeerTrailRejectionMessage))/
sizeof (struct GNUNET_PeerIdentity);
if ((msize - sizeof (struct PeerTrailRejectionMessage)) %
return GNUNET_OK;
}
- trail_peer_list = (struct GNUNET_PeerIdentity *)&trail_rejection[1];
+ trail_peer_list = (const struct GNUNET_PeerIdentity *)&trail_rejection[1];
is_predecessor = ntohl (trail_rejection->is_predecessor);
congestion_timeout = trail_rejection->congestion_time;
source = trail_rejection->source_peer;
trail_id = trail_rejection->trail_id;
ultimate_destination_finger_value =
- trail_rejection->ultimate_destination_finger_value;
+ GNUNET_ntohll (trail_rejection->ultimate_destination_finger_value);
/* First set the congestion time of the friend that sent you this message. */
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer);
- target_friend->congestion_timestamp = GNUNET_TIME_absolute_add (GNUNET_TIME_absolute_get(),
- congestion_timeout);
+ target_friend->congestion_timestamp =
+ GNUNET_TIME_absolute_add (GNUNET_TIME_absolute_get(),
+ congestion_timeout);
+ /* I am the source peer which wants to setup the trail. Do nothing.
+ * send_find_finger_trail_task is scheduled periodically.*/
if(0 == (GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &source)))
- {
return GNUNET_OK;
- }
/* If I am congested then pass this message to peer before me in trail. */
if(GNUNET_YES == GDS_ROUTING_threshold_reached())
{
struct GNUNET_PeerIdentity *new_trail;
unsigned int new_trail_length;
-
+
+ /* Remove yourself from the trail setup so far. */
if (trail_length == 1)
{
new_trail = NULL;
}
else
{
- next_hop = &trail_peer_list[trail_length - 2];
+ memcpy (&next_hop , &trail_peer_list[trail_length - 2],
+ sizeof (struct GNUNET_PeerIdentity));
+
/* Remove myself from the trail. */
new_trail_length = trail_length -1;
new_trail = GNUNET_malloc (new_trail_length * sizeof (struct GNUNET_PeerIdentity));
my_identity, is_predecessor,
new_trail,new_trail_length,trail_id,
target_friend, CONGESTION_TIMEOUT);
- return GNUNET_YES;
+ GNUNET_free (new_trail);
+ return GNUNET_OK;
}
/* Look for next_hop to pass the trail setup message */
&next_destination,
&new_intermediate_trail_id,
is_predecessor);
-
- if (0 == (GNUNET_CRYPTO_cmp_peer_identity (next_hop, &my_identity)))/* This means I am the final destination */
+
+ /* Am I the final destination? */
+ if (0 == (GNUNET_CRYPTO_cmp_peer_identity (next_hop, &my_identity)))
{
+ /* Add an entry in routing table only
+ * 1. If I am not the original source which sent the request for trail setup
+ * 2. If trail length > 0.
+ * NOTE: In case trail length > 0 and source is my friend, then also I add
+ * an entry in routing table,as we will send a trail compression message
+ * later.
+ */
+ if ((0 != GNUNET_CRYPTO_cmp_peer_identity (&source, &my_identity)) ||
+ (trail_length > 0))
+ GNUNET_assert (GNUNET_YES == GDS_ROUTING_add (trail_id, *peer, my_identity));
+
if (0 == trail_length)
next_peer = source;
else
next_peer = trail_peer_list[trail_length-1];
-
+
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_peer);
GDS_NEIGHBOURS_send_trail_setup_result (source,
my_identity,
is_predecessor, trail_id,
&new_intermediate_trail_id);
}
+ GNUNET_free (next_hop);
return GNUNET_OK;
}
/*
- * Core handle for p2p trail tear down messages.
+ * If you are the new first friend, then update prev hop to source of this message
+ * else get the next hop and pass this message forward to ultimately reach
+ * new first_friend.
+ * Core handle for p2p trail tear compression messages.
* @param cls closure
* @param message message
* @param peer peer identity this notification is about
*/
static int
handle_dht_p2p_trail_compression (void *cls, const struct GNUNET_PeerIdentity *peer,
- const struct GNUNET_MessageHeader *message)
+ const struct GNUNET_MessageHeader *message)
{
- struct PeerTrailCompressionMessage *trail_compression;
+ const struct PeerTrailCompressionMessage *trail_compression;
struct GNUNET_PeerIdentity *next_hop;
- struct GNUNET_HashCode trail_id;
struct FriendInfo *target_friend;
+ struct GNUNET_HashCode trail_id;
size_t msize;
msize = ntohs (message->size);
+ /* Here we pass only the trail id. */
if (msize != sizeof (struct PeerTrailCompressionMessage))
{
GNUNET_break_op (0);
return GNUNET_OK;
}
-
- trail_compression = (struct PeerTrailCompressionMessage *) message;
+
+ trail_compression = (const struct PeerTrailCompressionMessage *) message;
trail_id = trail_compression->trail_id;
-
+ //FIXME: again check if peer is the correct peer. same logic as
+ //trail teardown make a generic function.
+
+ /* Am I the new first friend to reach to finger of this trail. */
if (0 == (GNUNET_CRYPTO_cmp_peer_identity (&(trail_compression->new_first_friend),
&my_identity)))
{
- if(0 != (GNUNET_CRYPTO_cmp_peer_identity (&(trail_compression->destination_peer),
- &my_identity)))
- {
- GDS_ROUTING_update_trail_prev_hop (trail_id,
- trail_compression->source_peer);
- }
- return GNUNET_OK;
+ /* Update your prev hop to source of this message. */
+ GDS_ROUTING_update_trail_prev_hop (trail_id,
+ trail_compression->source_peer);
+ return GNUNET_OK;
}
-
+
+ /* Pass the message to next hop to finally reach to new_first_friend. */
next_hop = GDS_ROUTING_get_next_hop (trail_id, GDS_ROUTING_SRC_TO_DEST);
if (NULL == next_hop)
{
- GNUNET_break (0); /*FIXME: How to handle this case. */
+ GNUNET_break (0);
return GNUNET_OK;
}
+
GNUNET_assert (GNUNET_YES == GDS_ROUTING_remove_trail (trail_id));
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
GDS_NEIGHBOURS_send_trail_compression (trail_compression->source_peer,
- trail_compression->destination_peer,
trail_id,
trail_compression->new_first_friend,
target_friend);
/**
+ * Remove entry from your own routing table and pass the message to next
+ * peer in the trail.
* Core handler for trail teardown message.
* @param cls closure
* @param message message
- * @param peer peer identity this notification is about
+ * @param peer sender of this messsage.
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
static int
handle_dht_p2p_trail_teardown (void *cls, const struct GNUNET_PeerIdentity *peer,
const struct GNUNET_MessageHeader *message)
{
- struct PeerTrailTearDownMessage *trail_teardown;
- struct GNUNET_HashCode trail_id;
+ const struct PeerTrailTearDownMessage *trail_teardown;
enum GDS_ROUTING_trail_direction trail_direction;
+ struct GNUNET_HashCode trail_id;
+ struct GNUNET_PeerIdentity *prev_hop;
+ struct GNUNET_PeerIdentity *next_hop;
size_t msize;
-
msize = ntohs (message->size);
+ /* Here we pass only the trail id. */
if (msize != sizeof (struct PeerTrailTearDownMessage))
{
GNUNET_break_op (0);
return GNUNET_OK;
}
-
- trail_teardown = (struct PeerTrailTearDownMessage *) message;
+
+ trail_teardown = (const struct PeerTrailTearDownMessage *) message;
trail_direction = ntohl (trail_teardown->trail_direction);
- trail_id = trail_teardown->TRAIL_ID;
-
- if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity,
- &trail_teardown->destination_peer))
+ trail_id = trail_teardown->trail_id;
+
+ /* Check if peer is the real peer from which we should get this message.*/
+ /* Get the prev_hop for this trail by getting the next hop in opposite direction. */
+ /* FIXME: is using negation of trail direction correct. */
+ prev_hop = GDS_ROUTING_get_next_hop (trail_id, !trail_direction);
+ if (0 != GNUNET_CRYPTO_cmp_peer_identity (prev_hop, peer))
{
- struct GNUNET_PeerIdentity *next_hop;
- struct FriendInfo *target_friend;
-
- next_hop = GDS_ROUTING_get_next_hop (trail_id, trail_direction);
- if (NULL == next_hop)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
-
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- next_hop);
- GNUNET_assert (GNUNET_YES == GDS_ROUTING_remove_trail (trail_id));
- GDS_NEIGHBOURS_send_trail_teardown (trail_teardown->source_peer,
- trail_teardown->destination_peer,
- trail_id, trail_direction,
- target_friend);
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
}
+ GNUNET_free_non_null (prev_hop);
+
+ next_hop = GDS_ROUTING_get_next_hop (trail_id, trail_direction);
+ if (NULL == next_hop)
+ {
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+ }
+
+ GNUNET_assert (GNUNET_YES == GDS_ROUTING_remove_trail (trail_id));
+
+ /* If next_hop is my_identity, it means I am the final destination. */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (next_hop, &my_identity))
+ return GNUNET_OK;
+
+ /* If not final destination, then send a trail teardown message to next hop.*/
+ GDS_NEIGHBOURS_send_trail_teardown (trail_id, trail_direction, next_hop);
+ GNUNET_free (next_hop);
return GNUNET_OK;
}
/**
- * Fixme: this function is called only in case in notify new successor, the new
- * successor wants to add the source of the peer as its predecessor. Identify
- * if there is any other use case where it is required and if yes then adapt the
- * code for it.
- * Core handle for p2p add trail message.
+ * Add an entry in your routing table. If you are destination of this message
+ * then next_hop in routing table should be your own identity. If you are NOT
+ * destination, then get the next hop and forward message to it.
+ * Core handle for p2p add trail message.
* @param cls closure
* @param message message
* @param peer peer identity this notification is about
handle_dht_p2p_add_trail (void *cls, const struct GNUNET_PeerIdentity *peer,
const struct GNUNET_MessageHeader *message)
{
- struct PeerAddTrailMessage *add_trail;
- struct GNUNET_PeerIdentity *trail;
+ const struct PeerAddTrailMessage *add_trail;
+ const struct GNUNET_PeerIdentity *trail;
struct GNUNET_HashCode trail_id;
struct GNUNET_PeerIdentity destination_peer;
struct GNUNET_PeerIdentity source_peer;
size_t msize;
msize = ntohs (message->size);
- if (msize != sizeof (struct PeerAddTrailMessage))
+ /* In this message we pass the whole trail from source to destination as we
+ * are adding that trail.*/
+ if (msize < sizeof (struct PeerAddTrailMessage))
{
GNUNET_break_op (0);
return GNUNET_OK;
}
- add_trail = (struct PeerAddTrailMessage *) message;
+ add_trail = (const struct PeerAddTrailMessage *) message;
trail_length = (msize - sizeof (struct PeerAddTrailMessage))/
sizeof (struct GNUNET_PeerIdentity);
if ((msize - sizeof (struct PeerAddTrailMessage)) %
return GNUNET_OK;
}
- if ((msize < sizeof (struct PeerAddTrailMessage) +
- trail_length * sizeof (struct GNUNET_PeerIdentity)) ||
- (trail_length >
- GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
- {
- GNUNET_break_op (0);
- return GNUNET_OK;
- }
-
- trail = (struct GNUNET_PeerIdentity *)&add_trail[1];
+ trail = (const struct GNUNET_PeerIdentity *)&add_trail[1];
destination_peer = add_trail->destination_peer;
source_peer = add_trail->source_peer;
trail_id = add_trail->trail_id;
- if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity,
- &destination_peer))
+ //FIXME: add a check that sender peer is not malicious. Make it a generic
+ // function so that it can be used in all other functions where we need the
+ // same functionality.
+
+ /* I am not the destination of the trail. */
+ if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &destination_peer))
{
struct FriendInfo *target_friend;
+ /* Get my location in the trail. */
my_index = search_my_index (trail, trail_length);
if (GNUNET_SYSERR == my_index)
{
next_hop = source_peer;
else
next_hop = trail[trail_length - 1];
-
+
+ /* Add in your routing table. */
GNUNET_assert (GNUNET_OK == GDS_ROUTING_add (trail_id, next_hop, *peer));
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
GDS_NEIGHBOURS_send_add_trail (source_peer, destination_peer, trail_id,
trail, trail_length, target_friend);
+ return GNUNET_OK;
}
+
+ /* I am the destination. Add an entry in routing table. */
+ GNUNET_assert (GNUNET_OK == GDS_ROUTING_add (trail_id, *peer, my_identity));
return GNUNET_OK;
}
/**
- *FIXME; call send_trail_teardown_message on all the trails of the finger that
- * you remove. Also you don't need to decerement friend trail count as that
- * friend is removed. But you can not send trail teardown message as the friend
- * is disconnected. then you don't have any next_hop. and in case there are
- * multiple trails. and friend is the first trail then you remove only the trail.
- * Iterate over finger_hashmap, and remove entries if finger is the disconnected
- * peer or if disconnected peer is the first friend in the trail to reach the
- * finger.
- * @param cls closure
- * @param key current public key
- * @param value value in the hash map
- * @return #GNUNET_YES if we should continue to
- * iterate,
- * #GNUNET_NO if not.
+ * Send trail teardown and free the finger trail in which the first
+ * friend to reach to a finger is disconnected_friend
+ * @param disconnected_friend PeerIdentity of friend which got disconnected
+ * @param remove_finger Finger whose trail we need to check if it has
+ * disconnected_friend as the first hop.
+ * @return Total number of trails in which disconnected_friend was the first
+ * hop.
*/
static int
-remove_matching_finger (void *cls,
- uint32_t key,
- void *value)
+remove_matching_trails (const struct GNUNET_PeerIdentity *disconnected_friend,
+ struct FingerInfo *remove_finger)
{
- struct FingerInfo *remove_finger = value;
- const struct GNUNET_PeerIdentity *disconnected_peer = cls;
- struct Trail *trail_list;
+ unsigned int matching_trails_count;
int i;
+
+ /* Number of trails with disconnected_friend as the first hop in the trail
+ * to reach from me to remove_finger, NOT including endpoints. */
+ matching_trails_count = 0;
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&remove_finger->finger_identity,
- disconnected_peer))
+ /* Iterate over all the trails of finger. */
+ for (i = 0; i < remove_finger->trails_count; i++)
{
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multihashmap32_remove (finger_hashmap,
- key,
- remove_finger));
- free_finger (remove_finger);
- return GNUNET_YES;
- }
+ struct Trail *trail;
+ trail = &remove_finger->trail_list[i];
+
+ if (GNUNET_NO == trail->is_present)
+ continue;
+
+ /* First friend to reach to finger is disconnected_peer. */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&trail->trail_head->peer,
+ disconnected_friend))
+ {
+ matching_trails_count++;
+ send_trail_teardown (remove_finger, trail);
+ if (trail->trail_length > 0)
+ free_trail (trail);
+ }
+ }
+ return matching_trails_count;
+}
- for (i = 0; i< remove_finger->trails_count; i++)
- {
- trail_list = &remove_finger->trail_list[i];
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&trail_list->trail_head->peer,
- disconnected_peer))
+
+/**
+ * Iterate over finger_table entries.
+ * 0. Ignore finger which is my_identity or if no valid entry present at
+ * that finger index.
+ * 1. If disconnected_friend is a finger, then free that entry. Don't send trail
+ * teardown message, as there is no trail to reach to a finger which is a friend.
+ * 2. Check if disconnected_friend is the first friend in the trail to reach to a finger.
+ * 2.1 Send trail teardown message across all the trails in which disconnected
+ * friend is the first friend in the trail. If disconnected_friend is the
+ * first friend in all the trails to reach finger, then remove the finger.
+ * @param disconnected_friend Peer identity of friend which got disconnected.
+ */
+static void
+remove_matching_fingers (const struct GNUNET_PeerIdentity *disconnected_friend)
+{
+ struct FingerInfo *remove_finger;
+ int removed_trails_count;
+ int i;
+
+ /* Iterate over finger table entries. */
+ for (i = 0; i < MAX_FINGERS; i++)
+ {
+ remove_finger = &finger_table[i];
+
+ /* No finger stored at this trail index. */
+ if (GNUNET_NO == remove_finger->is_present)
+ continue;
+
+ /* I am my own finger, then ignore this finger. */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&remove_finger->finger_identity,
+ &my_identity))
+ continue;
+
+ /* Is disconnected friend a finger? */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (disconnected_friend,
+ &remove_finger->finger_identity))
+ {
+ /* No trail to reach this finger as it is a friend, don't send
+ * trail_teardown message. */
+ remove_finger->is_present = GNUNET_NO;
+ memset ((void *)&finger_table[i], 0, sizeof (finger_table[i]));
+ continue;
+ }
+
+ /* Iterate over the list of trails to reach remove_finger. Check if
+ * disconnected_friend is the first friend in any of the trail. */
+ removed_trails_count = remove_matching_trails (disconnected_friend,
+ remove_finger);
+
+ /* All the finger trails had disconnected_friend as the first friend,
+ * so free the finger. */
+ if (removed_trails_count == remove_finger->trails_count)
{
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multihashmap32_remove (finger_hashmap,
- key,
- remove_finger));
- free_finger (remove_finger);
+ remove_finger->is_present = GNUNET_NO;
+ memset ((void *)&finger_table[i], 0, sizeof (finger_table[i]));
}
}
-
- return GNUNET_YES;
}
{
struct FriendInfo *remove_friend;
+ /* If disconnected to own identity, then return. */
if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
return;
- remove_friend =
- GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer);
-
- if (NULL == remove_friend)
- {
- GNUNET_break (0);
- return;
- }
-
- GNUNET_assert (GNUNET_SYSERR !=
- GNUNET_CONTAINER_multihashmap32_iterate (finger_hashmap,
- &remove_matching_finger,
- (void *)peer));
+ GNUNET_assert (NULL != (remove_friend =
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer)));
+
+ /* Remove fingers with peer as first friend or if peer is a finger. */
+ remove_matching_fingers (peer);
+
+ /* Remove any trail from routing table of which peer is a part of. This function
+ * internally sends a trail teardown message in the direction of which
+ * disconnected peer is not part of. */
GDS_ROUTING_remove_trail_by_peer (peer);
+
+ /* Remove peer from friend_peermap. */
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_remove (friend_peermap,
peer,
remove_friend));
-
+
if (0 != GNUNET_CONTAINER_multipeermap_size (friend_peermap))
return;
+ /* If there are no more friends in friend_peermap, then don't schedule
+ * find_finger_trail_task. */
if (GNUNET_SCHEDULER_NO_TASK != find_finger_trail_task)
{
GNUNET_SCHEDULER_cancel (find_finger_trail_task);
}
else
GNUNET_break (0);
+
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connected to %s\n", GNUNET_i2s (peer_identity));
/* If peer already exists in our friend_peermap, then exit. */
- if (GNUNET_YES == GNUNET_CONTAINER_multipeermap_contains (friend_peermap, peer_identity))
+ if (GNUNET_YES == GNUNET_CONTAINER_multipeermap_contains (friend_peermap,
+ peer_identity))
{
GNUNET_break (0);
return;
peer_identity, friend,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
- /* got a first connection, good time to start with FIND FINGER TRAIL requests... */
+
+ /* got a first connection, good time to start with FIND FINGER TRAIL requests...*/
if (GNUNET_SCHEDULER_NO_TASK == find_finger_trail_task)
find_finger_trail_task = GNUNET_SCHEDULER_add_now (&send_find_finger_trail_message, NULL);
}
const struct GNUNET_PeerIdentity *identity)
{
my_identity = *identity;
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "my_indentity = %s\n",GNUNET_i2s(&my_identity));
+ FPRINTF (stderr,_("\nSUPU %s, %s, %d, my_identity = %s"),
+ __FILE__, __func__,__LINE__, GNUNET_i2s (&my_identity));
+}
+
+
+/**
+ * Initialize finger table entries.
+ */
+static void
+finger_table_init ()
+{
+ int i;
+ int j;
+
+ for(i = 0; i < MAX_FINGERS; i++)
+ {
+ finger_table[i].is_present = GNUNET_NO;
+ for (j = 0; j < MAXIMUM_TRAILS_PER_FINGER; j++)
+ finger_table[i].trail_list[j].is_present = GNUNET_NO;
+ memset ((void *)&finger_table[i], 0, sizeof (finger_table[i]));
+
+ }
}
{&handle_dht_p2p_verify_successor, GNUNET_MESSAGE_TYPE_DHT_P2P_VERIFY_SUCCESSOR, 0},
{&handle_dht_p2p_verify_successor_result, GNUNET_MESSAGE_TYPE_DHT_P2P_VERIFY_SUCCESSOR_RESULT, 0},
{&handle_dht_p2p_notify_new_successor, GNUNET_MESSAGE_TYPE_DHT_P2P_NOTIFY_NEW_SUCCESSOR, 0},
- {&handle_dht_p2p_trail_rejection, GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_REJECTION, 0},
- {&handle_dht_p2p_trail_compression, GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_COMPRESSION, 0},
- {&handle_dht_p2p_trail_teardown, GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_TEARDOWN, 0},
+ {&handle_dht_p2p_trail_setup_rejection, GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP_REJECTION, 0},
+ {&handle_dht_p2p_trail_compression, GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_COMPRESSION,
+ sizeof (struct PeerTrailCompressionMessage)},
+ {&handle_dht_p2p_trail_teardown, GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_TEARDOWN,
+ sizeof (struct PeerTrailTearDownMessage)},
{&handle_dht_p2p_add_trail, GNUNET_MESSAGE_TYPE_DHT_P2P_ADD_TRAIL, 0},
{NULL, 0, 0}
};
return GNUNET_SYSERR;
friend_peermap = GNUNET_CONTAINER_multipeermap_create (256, GNUNET_NO);
- finger_hashmap = GNUNET_CONTAINER_multihashmap32_create (MAX_FINGERS * 4/3);
-
+ finger_table_init ();
+
return GNUNET_OK;
}
+
/**
* Shutdown neighbours subsystem.
*/
GNUNET_CONTAINER_multipeermap_destroy (friend_peermap);
friend_peermap = NULL;
- GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap32_size (finger_hashmap));
- GNUNET_CONTAINER_multihashmap32_destroy (finger_hashmap);
- finger_hashmap = NULL;
-
if (GNUNET_SCHEDULER_NO_TASK != find_finger_trail_task)
{
GNUNET_break (0);
projects / oweals / gnunet.git / blobdiff