#include <fenv.h>
#include "dht.h"
-/* TODO:
- 1. to randomly choose one of the routes in case there are multiple
- routes to reach to the finger.
- 2. Structure alignment.
- 3. In put, we don't have anything like put result. so we are not adding anything
- in the routing table.
- 4. Maintain a list of trails --> struct Trail *all_trails_head
- * struct Trail *all_trails_tail. How do I keep it as an array and not as a list??
- * First will complete the logic everywhere and then make this change.
- 5. At some places you use memcpy and at some places =, use uniformly.
- 6. I have removed compare_and_update_predecessor from handle_dht_p2p_Trail_setup
- * (refer to google docs for reason).
-*/
+/**
+ * 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 of a peer.
+ * Maximum possible fingers (including predecessor) of a peer
*/
-#define MAX_FINGERS 66
+#define MAX_FINGERS 65
/**
* Maximum allowed number of pending messages per friend 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)
+
+/**
+ * Duration for which I may remain congested.
+ * Note: Its a static value. In future, a peer may do some analysis and calculate
+ * congestion_timeout based on 'some' parameters.
+ */
+#define CONGESTION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 2)
+
+/**
+ * Maximum number of trails allowed to go through a friend.
*/
-#define GET_TIMEOUT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
+#define TRAILS_THROUGH_FRIEND_THRESHOLD 64
/**
* Maximum number of trails stored per finger.
*/
-#define TRAILS_COUNT 2
+#define MAXIMUM_TRAILS_PER_FINGER 1
+
+/**
+ * Finger map index for predecessor entry in finger table.
+ */
+#define PREDECESSOR_FINGER_ID 64
+
+/**
+ * Wrap around in peer identity circle.
+ */
+#define PEER_IDENTITES_WRAP_AROUND pow(2, 64) - 1
/**
- * Used to distinguish put/get request use of find_successor() from others
+ * FIXME: Its use only at 3 places check if you can remove it.
+ * To check if a finger is predecessor or not.
*/
-#define PUT_GET_REQUEST 68
+enum GDS_NEIGHBOURS_finger_type
+{
+ GDS_FINGER_TYPE_PREDECESSOR = 0,
+ GDS_FINGER_TYPE_NON_PREDECESSOR = 1
+};
GNUNET_NETWORK_STRUCT_BEGIN
-
+
/**
* P2P PUT message
*/
uint32_t put_path_length GNUNET_PACKED;
/**
- * Current destination to which this message is forwarded.
+ * Best known destination (could be my friend or finger) which should
+ * get this message next.
*/
- struct GNUNET_PeerIdentity current_destination;
+ struct GNUNET_PeerIdentity best_known_destination;
/**
- * Peer whose finger is current_destination.
+ * In case best_known_destination is a finger, then trail to reach
+ * to that finger. Else its default value is 0.
*/
- struct GNUNET_PeerIdentity current_source;
+ struct GNUNET_HashCode intermediate_trail_id;
/**
* When does the content expire?
};
-
-/**
- * P2P Result message
- */
-struct PeerGetResultMessage
-{
- /**
- * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_GET_RESULT
- */
- struct GNUNET_MessageHeader header;
-
- /**
- * The type for the data.
- */
- uint32_t type GNUNET_PACKED;
-
- /**
- * Peer which will receive the get result message.
- */
- struct GNUNET_PeerIdentity source_peer;
-
- /**
- * Number of peers recorded in the outgoing path from source to the
- * stored location of this message.
- */
- uint32_t put_path_length GNUNET_PACKED;
-
- /**
- * Length of the GET path that follows (if tracked).
- */
- uint32_t get_path_length GNUNET_PACKED;
-
- /**
- * When does the content expire?
- */
- struct GNUNET_TIME_Absolute expiration_time;
-
- /**
- * The key of the corresponding GET request.
- */
- struct GNUNET_HashCode key;
-
- /* put path (if tracked) */
-
- /* get path (if tracked) */
-
- /* Payload */
-
-};
-
-
/**
* P2P GET message
*/
unsigned int get_path_length;
/**
- * Peer which is an intermediate destination.
+ * Best known destination (could be my friend or finger) which should
+ * get this message next.
*/
- struct GNUNET_PeerIdentity current_destination;
+ struct GNUNET_PeerIdentity best_known_destination;
/**
- * Source for which current_destination is the finger.
+ * In case best_known_destination is a finger, then trail to reach
+ * to that finger. Else its default value is 0.
*/
- struct GNUNET_PeerIdentity current_source;
+ struct GNUNET_HashCode intermediate_trail_id;
/**
* The key we are looking for.
};
-
/**
- * P2P Trail setup message
+ * P2P Result message
*/
-struct PeerTrailSetupMessage
+struct PeerGetResultMessage
{
-
/**
- * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP
+ * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_GET_RESULT
*/
struct GNUNET_MessageHeader header;
-
- /**
- * Successor of this finger value will be our finger peer.
- */
- uint64_t destination_finger;
/**
- * Source peer which wants to setup the trail to one of its finger.
+ * The type for the data.
*/
- struct GNUNET_PeerIdentity source_peer;
+ uint32_t type GNUNET_PACKED;
/**
- * Peer to which this packet is forwarded.
+ * Number of peers recorded in the outgoing path from source to the
+ * stored location of this message.
*/
- struct GNUNET_PeerIdentity current_destination;
+ uint32_t put_path_length GNUNET_PACKED;
/**
- * In case the packet is forwarded to an intermediate finger, then
- * current_source contains the peer id whose finger is the intermediate
- * finger. In case the packet is forwarded to a friend, then it is NULL.
- * FIXME: check the usage of current_source and fix this comment.
+ * Length of the GET path that follows (if tracked).
*/
- struct GNUNET_PeerIdentity current_source;
+ uint32_t get_path_length GNUNET_PACKED;
/**
- * Index into finger peer map, in Network Byte Order.
+ * Peer which queried for get and should get the result.
*/
- uint32_t finger_map_index;
+ struct GNUNET_PeerIdentity querying_peer;
/**
- * Number of entries in trail list, in Network Byte Order.
+ * When does the content expire?
*/
- uint32_t trail_length GNUNET_PACKED;
-
- /* Trail formed in the process. */
-};
+ struct GNUNET_TIME_Absolute expiration_time;
+
+ /**
+ * The key of the corresponding GET request.
+ */
+ struct GNUNET_HashCode key;
+
+ /* put path (if tracked) */
+
+ /* get path (if tracked) */
+
+ /* Payload */
+};
/**
- * P2P Trail Setup Result message
+ * P2P Trail setup message
*/
-struct PeerTrailSetupResultMessage
+struct PeerTrailSetupMessage
{
-
/**
- * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP_RESULT
+ * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP
*/
struct GNUNET_MessageHeader header;
/**
- * Finger to which we have found the path.
+ * Is source_peer trying to setup the trail to a predecessor or any finger.
*/
- struct GNUNET_PeerIdentity finger_identity;
+ uint32_t is_predecessor;
+
+ /**
+ * Peer closest to this value will be our finger.
+ */
+ uint64_t final_destination_finger_value;
/**
- * Peer which was looking for the trail to finger.
+ * Source peer which wants to setup the trail to one of its finger.
*/
- struct GNUNET_PeerIdentity destination_peer;
-
+ struct GNUNET_PeerIdentity source_peer;
+
/**
- * Index into finger peer map in NBO.
+ * Best known destination (could be my friend or finger) which should
+ * get this message next.
*/
- uint32_t finger_map_index;
-
+ struct GNUNET_PeerIdentity best_known_destination;
+
/**
- * Number of entries in trail list in NBO.
+ * In case best_known_destination is a finger, then trail id of trail to
+ * reach to this finger.
*/
- uint32_t trail_length GNUNET_PACKED;
+ struct GNUNET_HashCode intermediate_trail_id;
- /* Trail from destination_peer to finger_identity */
-
-};
+ /**
+ * Trail id for trail which we are trying to setup.
+ */
+ struct GNUNET_HashCode 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[]
+ */
+};
/**
- * P2P Trail Rejection Message.
+ * P2P Trail Setup Result message
*/
-struct PeerTrailRejectionMessage
+struct PeerTrailSetupResultMessage
{
+
/**
- * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_REJECTION
+ * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP_RESULT
*/
struct GNUNET_MessageHeader header;
-
+
/**
- * Source peer which wants to set up the trail.
+ * Finger to which we have found the path.
*/
- struct GNUNET_PeerIdentity source_peer;
-
+ struct GNUNET_PeerIdentity finger_identity;
+
/**
- * Peer which sent trail rejection message.
+ * Peer which started trail_setup to find trail to finger_identity
*/
- struct GNUNET_PeerIdentity congested_peer;
-
+ struct GNUNET_PeerIdentity querying_peer;
+
/**
- * Peer identity which will be successor to this value will be finger of
- * source_peer.
+ * Is the trail setup to querying_peer's predecessor or finger?
*/
- uint64_t finger_identity_value;
-
+ uint32_t is_predecessor;
+
/**
- * Index in finger peer map of source peer.
+ * Value to which finger_identity is the closest peer.
*/
- uint32_t finger_map_index;
+ uint64_t ulitmate_destination_finger_value;
/**
- * Total number of peers in the trail.
+ * Identifier of the trail from querying peer to finger_identity, NOT
+ * including both endpoints.
*/
- uint32_t trail_length;
-
- /* Trail_list from source_peer to peer which sent the message for trail setup
- * to congested peer.*/
-};
+ struct GNUNET_HashCode trail_id;
+ /* List of peers which are part of the trail from querying peer to
+ * finger_identity, NOT including both endpoints.
+ * struct GNUNET_PeerIdentity trail[]
+ */
+};
/**
- * P2P Verify Successor message.
+ * P2P Verify Successor Message.
*/
struct PeerVerifySuccessorMessage
{
-
/**
* Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_VERIFY_SUCCESSOR
*/
struct GNUNET_MessageHeader header;
-
+
/**
- * Source peer which wants to verify its successor.
+ * Peer which wants to verify its successor.
*/
struct GNUNET_PeerIdentity source_peer;
-
+
/**
- * My current successor.
+ * Source Peer's current successor.
*/
struct GNUNET_PeerIdentity successor;
-
+
/**
- * Total number of peers in trail to current successor.
+ * Identifier of trail to reach from source_peer to successor.
*/
- uint32_t trail_length;
-
- /* Trail to reach to from source_peer to successor. */
-};
+ struct GNUNET_HashCode trail_id;
+ /* List of the peers which are part of trail to reach from source_peer
+ * to successor, NOT including them
+ * struct GNUNET_PeerIdentity trail[]
+ */
+};
/**
- * P2P Verify Successor Result message.
+ * P2P Verify Successor Result Message
*/
struct PeerVerifySuccessorResultMessage
{
-
/**
* Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_VERIFY_SUCCESSOR_RESULT
*/
struct GNUNET_MessageHeader header;
-
+
/**
- * Destination peer which sent the request to verify its successor.
+ * Peer which sent the request to verify its successor.
*/
- struct GNUNET_PeerIdentity destination_peer;
-
+ struct GNUNET_PeerIdentity querying_peer;
+
/**
* Successor to which PeerVerifySuccessorMessage was sent.
*/
- struct GNUNET_PeerIdentity source_successor;
-
+ struct GNUNET_PeerIdentity current_successor;
+
/**
- * source_successor's predecessor
+ * Current Predecessor of source_successor. It can be same as querying peer
+ * or different. In case it is different then it can be querying_peer's
+ * probable successor.
*/
- struct GNUNET_PeerIdentity my_predecessor;
-
+ struct GNUNET_PeerIdentity probable_successor;
+
/**
- * Total number of peers in trail.
+ * Trail identifier of trail from querying_peer to current_successor.
*/
- uint32_t trail_length;
-
- /* Trail to reach from destination_peer to its correct successor.
- * If source_successor is not destination peer, then trail is from destination_peer
- * to my_predecessor.
- * If source_successor is destination peer, then trail is from destination_peer
- * to source_successor. */
-};
+ struct GNUNET_HashCode trail_id;
+
+ /**
+ * Direction in which we are looking at the trail.
+ */
+ uint32_t trail_direction;
+ /* In case probable_successor != querying_peer, then trail to reach from
+ * querying_peer to probable_successor, NOT including end points.
+ * struct GNUNET_PeerIdentity trail[]
+ */
+};
/**
- * P2P Notify New Successor message.
+ * P2P Notify New Successor Message.
*/
struct PeerNotifyNewSuccessorMessage
{
* Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_NOTIFY_NEW_SUCCESSOR
*/
struct GNUNET_MessageHeader header;
-
+
/**
- * Source peer which wants to notify its new successor.
+ * Peer which wants to notify its new successor.
*/
struct GNUNET_PeerIdentity source_peer;
-
- /**
- * Old successor of source peer.
- */
- struct GNUNET_PeerIdentity old_successor;
-
+
/**
- * New successor identity.
+ * New successor of source_peer.
*/
- struct GNUNET_PeerIdentity destination_peer;
-
+ struct GNUNET_PeerIdentity new_successor;
+
/**
- * Number of peers in trail from source_peer to new successor.
+ * Unique identifier of the trail from source_peer to new_successor,
+ * NOT including the endpoints.
+ */
+ struct GNUNET_HashCode trail_id;
+
+ /* List of peers in trail from source_peer to new_successor,
+ * NOT including the endpoints.
+ * struct GNUNET_PeerIdentity trail[]
*/
- uint32_t trail_length;
-
- /* Trail to from source_peer to destination_peer. */
};
-struct PeerTrailTearDownMessage
+/**
+ * P2P Trail Compression Message.
+ */
+struct PeerTrailCompressionMessage
{
/**
- * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_TEARDOWN
+ * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_COMPRESSION
*/
struct GNUNET_MessageHeader header;
-
+
/**
- * Source peer of this trail.
+ * Source peer of this trail.
*/
struct GNUNET_PeerIdentity source_peer;
-
- /**
- * Destination peer 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
- * destination.
+ * Trail from source_peer to destination_peer compressed such that
+ * new_first_friend is the first hop in the trail from source to
+ * destination.
*/
struct GNUNET_PeerIdentity new_first_friend;
+
/**
- * Number of peers in trail from source_peer to new first friend.
+ * Unique identifier of trail.
*/
- uint32_t trail_length;
-
- /* Trail from source_peer to new first friend. */
+ struct GNUNET_HashCode trail_id;
};
-struct PeerAddTrailMessage
+/**
+ * P2P Trail Tear Down message.
+ */
+struct PeerTrailTearDownMessage
{
/**
- * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_ADD_TRAIL
+ * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_TEARDOWN
*/
struct GNUNET_MessageHeader header;
-
- /**
- * Source peer of the routing trail.
- */
- struct GNUNET_PeerIdentity source_peer;
-
+
/**
- * Destination peer of the routing trail.
+ * Unique identifier of the trail.
*/
- struct GNUNET_PeerIdentity destination_peer;
-
+ struct GNUNET_HashCode trail_id;
+
/**
- * Total number of peers from source peer to destination peer.
+ * Direction of trail.
*/
- unsigned int trail_length;
-
- /* Trail from source peer to destination peer. */
-
+ uint32_t trail_direction;
};
-GNUNET_NETWORK_STRUCT_END
-
/**
- * Linked list of messages to send to a particular other peer.
+ * P2P Trail Rejection Message.
*/
-struct P2PPendingMessage
+struct PeerTrailRejectionMessage
{
/**
- * Pointer to next item in the list
+ * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP_REJECTION
*/
- struct P2PPendingMessage *next;
+ struct GNUNET_MessageHeader header;
/**
- * Pointer to previous item in the list
+ * Peer which wants to set up the trail.
*/
- struct P2PPendingMessage *prev;
+ struct GNUNET_PeerIdentity source_peer;
/**
- * Message importance level. FIXME: used? useful?
+ * Peer which sent trail rejection message as it it congested.
*/
- unsigned int importance;
-
+ struct GNUNET_PeerIdentity congested_peer;
+
/**
- * When does this message time out?
+ * Peer identity closest to this value will be finger of
+ * source_peer.
*/
- struct GNUNET_TIME_Absolute timeout;
+ uint64_t ultimate_destination_finger_value;
+
+ /**
+ * Is source_peer trying to setup the trail to its predecessor or finger.
+ */
+ uint32_t is_predecessor;
+
+ /**
+ * Identifier for the trail that source peer is trying to setup.
+ */
+ struct GNUNET_HashCode trail_id;
/**
- * Actual message to be sent, allocated at the end of the struct:
- * // msg = (cast) &pm[1];
- * // memcpy (&pm[1], data, len);
+ * Relative time for which congested_peer will remain congested.
*/
- const struct GNUNET_MessageHeader *msg;
+ struct GNUNET_TIME_Relative congestion_time;
+ /* Trail_list from source_peer to peer which sent the message for trail setup
+ * to congested peer. This trail does NOT include source_peer.
+ struct GNUNET_PeerIdnetity trail[]*/
};
-
/**
- * Linked List of peers which are part of trail to reach a particular Finger.
+ * P2P Add Trail Message.
*/
-struct TrailPeerList
+struct PeerAddTrailMessage
{
- /**
- * Pointer to next item in the list
- */
- struct TrailPeerList *next;
+ /**
+ * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_ADD_TRAIL
+ */
+ struct GNUNET_MessageHeader header;
- /**
- * Pointer to previous item in the list
- */
- struct TrailPeerList *prev;
-
- /**
- * An element in this trail list
- */
- struct GNUNET_PeerIdentity peer;
-
+ /**
+ * Source of the routing trail.
+ */
+ struct GNUNET_PeerIdentity source_peer;
+
+ /**
+ * Destination of the routing trail.
+ */
+ struct GNUNET_PeerIdentity destination_peer;
+
+ /**
+ * Unique identifier of the trail from source_peer to destination_peer,
+ * NOT including the endpoints.
+ */
+ struct GNUNET_HashCode trail_id;
+
+ /* Trail from source peer to destination peer, NOT including them.
+ * struct GNUNET_PeerIdentity trail[]
+ */
};
+GNUNET_NETWORK_STRUCT_END
+
+/**
+ * Linked list of messages to send to a particular other peer.
+ */
+struct P2PPendingMessage
+{
+ /**
+ * Pointer to next item in the list
+ */
+ struct P2PPendingMessage *next;
+
+ /**
+ * Pointer to previous item in the list
+ */
+ struct P2PPendingMessage *prev;
+
+ /**
+ * Message importance level. FIXME: used? useful?
+ */
+ unsigned int importance;
+
+ /**
+ * When does this message time out?
+ */
+ struct GNUNET_TIME_Absolute timeout;
+
+ /**
+ * Actual message to be sent, allocated at the end of the struct:
+ * // msg = (cast) &pm[1];
+ * // memcpy (&pm[1], data, len);
+ */
+ const struct GNUNET_MessageHeader *msg;
+
+};
-/**
- * FIXME: for congested peer just define a relative time as #define.
+/**
* Entry in friend_peermap.
*/
struct FriendInfo
{
/**
- * Friend Identity
+ * Friend Identity
*/
struct GNUNET_PeerIdentity id;
/**
- * Number of trails for which this friend is the first hop.
+ * Number of trails for which this friend is the first hop or if the friend
+ * is finger.
*/
unsigned int trails_count;
-
+
/**
* Count of outstanding messages for this friend.
*/
unsigned int pending_count;
-
+
/**
- * FIXME: Refer to time.c and gnunet_time_lib.h for correct functions.
- * in handle_dht_p2p_trail_rejection, you should update these values
- * and whenever you are selecting a friend in select_random_friend()
- * and find_successor(), you should check congestion_duration = 0,
- * then proceed else if congestion_duration < your current time then also
- * proceed.
- * struct GNUNET_TIME_Absolute start = GNUNET_TIME_absolute_get();
- * struct GNUNET_TIME_Relative congestion_timeout =
- * congestion_duration = GNUNET_TIME_absolute_add (start,congestion_timeout);
- * in select_random_friend, GNUNET_TIME_absolute_get_remaning()
+ * In case not 0, then amount of time for which this friend is congested.
*/
- struct GNUNET_TIME_Absolute congestion_duration;
-
+ struct GNUNET_TIME_Absolute congestion_timestamp;
+
/**
* Head of pending messages to be sent to this friend.
*/
* Tail of pending messages to be sent to this friend.
*/
struct P2PPendingMessage *tail;
-
+
/**
* Core handle for sending messages to this friend.
*/
};
+/**
+ * An individual element of the trail to reach to a finger.
+ */
+struct Trail_Element
+{
+ /**
+ * Pointer to next item in the list
+ */
+ struct Trail_Element *next;
+
+ /**
+ * Pointer to prev item in the list
+ */
+ struct Trail_Element *prev;
+
+ /**
+ * An element in this trail.
+ */
+ struct GNUNET_PeerIdentity peer;
+};
/**
- * FIXME: make an array of trails. #define number of entries in the array =
- * number of trails we want to keep. Remove head, tail of trails.
- * Entry in finger_peermap.
+ * FIXME: removed first_friend_trails_count, need to write a function
+ * to calculate each time we need it. Else, keep a pointer to first
+ * friend of in the trail.
+ * Information about an individual trail.
*/
-struct FingerInfo
+struct Trail
{
/**
- * Finger identity.
+ * Head of trail.
*/
- struct GNUNET_PeerIdentity finger_identity;
-
+ struct Trail_Element *trail_head;
+
/**
- * Index in finger peer map
+ * Tail of trail.
*/
- unsigned int finger_map_index;
-
+ struct Trail_Element *trail_tail;
+
/**
- * Number of trails to reach to this finger.
+ * Unique identifier of this trail.
*/
- unsigned int trail_count;
-
+ struct GNUNET_HashCode trail_id;
+
/**
- * Total number of entries in first trail from (me,finger)
+ * Length of trail pointed
*/
- unsigned int first_trail_length;
+ unsigned int trail_length;
/**
- * Total number of entries in second trail from (me,finger)
+ * Is there a valid trail entry.
*/
- unsigned int second_trail_length;
-
-
+ unsigned int is_present;
+};
+
+/**
+ * An entry in finger_table
+ */
+struct FingerInfo
+{
/**
- * Number of trail of which the first element to reach to this finger is
- * part of.
+ * Finger identity.
*/
- unsigned int first_friend_trails_count;
-
+ struct GNUNET_PeerIdentity finger_identity;
+
/**
- * Head of first trail to reach this finger.
+ * Is any finger stored at this finger index.
*/
- struct TrailPeerList *first_trail_head;
+ unsigned int is_present;
/**
- * Tail of first trail to reach this finger.
+ * Index in finger peer map
*/
- struct TrailPeerList *first_trail_tail;
-
+ uint32_t finger_table_index;
+
/**
- * Head of second trail to reach this finger.
+ * Number of trails setup so far for this finger.
+ * Should not cross MAXIMUM_TRAILS_PER_FINGER.
*/
- struct TrailPeerList *second_trail_head;
-
+ uint32_t trails_count;
+
/**
- * Tail of second trail to reach this finger.
+ * Array of trails to reach to this finger.
*/
- struct TrailPeerList *second_trail_tail;
-
+ struct Trail trail_list[MAXIMUM_TRAILS_PER_FINGER];
};
/**
- * FIXME: The name is not correct.
- * Used to specify the kind of value stored in the array all_known_peers.
+ * Data structure to keep track of closest peer seen so far in find_successor()
*/
-enum current_destination_type
+struct Closest_Peer
{
- FRIEND,
- FINGER,
- VALUE,
- MY_ID
-};
+ /**
+ * Destination finger vaule.
+ */
+ uint64_t destination_finger_value;
+
+ /**
+ * Is finger value predecessor or any other finge
+ */
+ unsigned int is_predecessor;
+
+ /**
+ * Trail id to reach to peer.
+ */
+ struct GNUNET_HashCode trail_id;
+
+ /**
+ * FIXME: see the usage of this field and write comment.
+ */
+ struct GNUNET_PeerIdentity next_hop;
+ /**
+ * Next destination. In case of friend and my_identity , it is same as next_hop
+ * In case of finger it is finger identity.
+ */
+ struct GNUNET_PeerIdentity best_known_destination;
+};
/**
- * Data structure passed to sorting algorithm in find_successor().
+ * FIXME: now I have removed the first_friend_trail_count,
+ * Need to update the code to find the count.
+ * Data structure to store the trail chosen to reach to finger.
*/
-struct Sorting_List
+struct Selected_Finger_Trail
{
/**
- * 64 bit value of peer identity
+ * First friend in the trail to reach finger.
*/
- uint64_t peer_id;
-
+ struct FriendInfo friend;
+
/**
- * FIXME: think of a better name for both the struct and destination_type
- * Type : MY_ID, FINGER, FINGER, Value
+ * Identifier of this trail.
*/
- enum current_destination_type type;
-
+ struct GNUNET_HashCode trail_id;
+
/**
- * Pointer to original data structure linked to peer id.
+ * Total number of peers in this trail.
*/
- void *data;
+ unsigned int trail_length;
};
-
/**
* Task that sends FIND FINGER TRAIL requests. This task is started when we have
- * get our first friend.
+ * get our first friend.
*/
static GNUNET_SCHEDULER_TaskIdentifier find_finger_trail_task;
static struct GNUNET_PeerIdentity my_identity;
/**
- * Hash map of all the friends of a peer
+ * Peer map of all the friends of a peer
*/
static struct GNUNET_CONTAINER_MultiPeerMap *friend_peermap;
/**
- * Hash map of all the fingers of a peer
+ * Array of all the fingers.
*/
-static struct GNUNET_CONTAINER_MultiPeerMap *finger_peermap;
+static struct FingerInfo finger_table [MAX_FINGERS];
/**
* Handle to CORE.
static struct GNUNET_CORE_Handle *core_api;
/**
- * Finger map index for predecessor entry in finger peermap.
- */
-#define PREDECESSOR_FINGER_ID 64
-
-/**
- * Maximum number of trails allowed to go through a friend.
- * FIXME: Better name, Random value at the moment, need to be adjusted to maintain a balance
- * between performance and Sybil tolerance.
- */
-#define TRAIL_THROUGH_FRIEND_THRESHOLD 64
-
-/**
- * Possible number of different trails to reach to a finger. (Redundant routing)
- */
-#define TRAIL_COUNT 2
-
-/**
- * The current finger index that we have want to find trail to.
+ * The current finger index that we have want to find trail to. We start the
+ * search with value = 0, i.e. successor and then go to PREDCESSOR_FINGER_ID
+ * and decrement it. For any index 63 <= index < 0, if finger is same as successor,
+ * we reset this index to 0.
*/
static unsigned int current_search_finger_index;
-/**
- * Iterate over trail and search your index location in the array.
- * @param trail Trail which contains list of peers.
- * @param trail_length Number of peers in the trail.
- * @return Index in the array.
- * #GNUNET_SYSERR, in case there is no entry which should not be the case ideally.
- */
-static int
-search_my_index (const struct GNUNET_PeerIdentity *trail,
- int trail_length)
-{
- int i = 0;
-
- while (i < trail_length)
- {
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &trail[i]))
- {
- return i;
- }
- i++;
- }
- return GNUNET_SYSERR;
-}
-
-/**
- * Compare two peer identities.
- * @param p1 Peer identity
- * @param p2 Peer identity
- * @return 1 if p1 > p2, -1 if p1 < p2 and 0 if p1 == p2.
- */
-static int
-compare_peer_id (const void *p1, const void *p2)
-{
- struct Sorting_List *p11;
- struct Sorting_List *p22;
- int ret;
- p11 = GNUNET_malloc (sizeof (struct Sorting_List));
- p22 = GNUNET_malloc (sizeof (struct Sorting_List));
- p11 = (struct Sorting_List *)p1;
- p22 = (struct Sorting_List *)p2;
- ret = ( (p11->peer_id) > (p22->peer_id) ) ? 1 :
- ( (p11->peer_id) == (p22->peer_id) ) ? 0 : -1;
- return ret;
-}
-
-
-/**
- * Return the predecessor of value in all_known_peers.
- * @param all_known_peers list of all the peers
- * @param value value we have to search in the all_known_peers.
- * @param size Total numbers of elements
- * @return Predecessor
- */
-static struct Sorting_List *
-find_closest_predecessor(struct Sorting_List *all_known_peers, uint64_t value,
- unsigned int size)
-{
- int first;
- int last;
- int middle;
-
- first = 0;
- last = size - 1;
- middle = (first + last)/2;
-
- while(first <= last)
- {
- if(all_known_peers[middle].peer_id < value)
- {
- first = middle + 1;
- }
- else if(all_known_peers[middle].peer_id == value)
- {
- if(middle == 0)
- {
- return &all_known_peers[size - 1];
- }
- else
- {
- return &all_known_peers[middle - 1];
- }
- }
- else
- {
- last = middle - 1;
- }
-
- middle = (first + last)/2;
- }
- return NULL;
-}
-
-
-/**
- * Return the successor of value in all_known_peers.
- * @param all_known_peers list of all the peers
- * @param value value we have to search in the all_known_peers.
- * @param size Total numbers of elements
- * @return Successor
- */
-static struct Sorting_List *
-find_closest_successor(struct Sorting_List *all_known_peers, uint64_t value,
- unsigned int size)
-{
- int first;
- int last;
- int middle;
-
- first = 0;
- last = size - 1;
- middle = (first + last)/2;
-
- while(first <= last)
- {
- if(all_known_peers[middle].peer_id < value)
- {
- first = middle + 1;
- }
- else if(all_known_peers[middle].peer_id == value)
- {
- if(middle == (size -1))
- {
- return &all_known_peers[0];
- }
- else
- {
- return &all_known_peers[middle+1];
- }
- }
- else
- {
- last = middle - 1;
- }
-
- middle = (first + last)/2;
- }
- return NULL;
-}
-
-
/**
* Called when core is ready to send a message we asked for
* out to the destination.
struct P2PPendingMessage *pending;
size_t off;
size_t msize;
-
+
peer->th = NULL;
while ((NULL != (pending = peer->head)) &&
(0 == GNUNET_TIME_absolute_get_remaining (pending->timeout).rel_value_us))
{
peer->pending_count--;
- GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
+ GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
GNUNET_free (pending);
}
if (NULL == pending)
&core_transmit_notify, peer);
GNUNET_break (NULL != peer->th);
}
-
+
return off;
}
process_friend_queue (struct FriendInfo *peer)
{
struct P2PPendingMessage *pending;
-
+
if (NULL == (pending = peer->head))
return;
if (NULL != peer->th)
return;
-
+
GNUNET_STATISTICS_update (GDS_stats,
gettext_noop
("# Bytes of bandwidth requested from core"),
ntohs (pending->msg->size), GNUNET_NO);
-
- /* FIXME: Are we correctly initializing importance and pending. */
+
peer->th =
GNUNET_CORE_notify_transmit_ready (core_api, GNUNET_NO,
pending->importance,
/**
- * Construct a trail setup message and forward it to a friend.
- * @param source_peer Peer which wants to set up the trail to one of its finger.
- * @param destination_finger Peer identity closest to this value will be
- * @a source_peer's finger.
- * @param current_destination next destination corresponding to @a current_source,
- * can be either a finger or a friend of @a current_source.
- * @param current_source Peer for which @a current_destination is its finger/friend.
- * @param target_friend Friend to which this message should be forwarded.
- * @param trail_length Numbers of peers in the trail found so far.
- * @param trail_peer_list Peers this request has traversed so far
- * @param finger_map_index Index in finger peer map
+ * 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
+ * @param ultimate_destination_finger_value Peer identity closest to this value
+ * will be finger to @a source_peer
+ * @param best_known_destination Best known destination (could be finger or friend)
+ * which should get this message.
+ * @param target_friend Friend to which message is forwarded now.
+ * @param trail_length Total number of peers in trail setup so far.
+ * @param trail_peer_list Trail setup so far
+ * @param is_predecessor Is source_peer looking for trail to a predecessor or not.
+ * @param trail_id Unique identifier for the trail we are trying to setup.
+ * @param intermediate_trail_id Trail id of intermediate trail to reach to
+ * best_known_destination when its a finger. If not
+ * used then set to 0.
*/
void
-GDS_NEIGHBOURS_send_trail_setup (const struct GNUNET_PeerIdentity *source_peer,
- uint64_t destination_finger,
- struct GNUNET_PeerIdentity *current_destination,
- struct GNUNET_PeerIdentity *current_source,
+GDS_NEIGHBOURS_send_trail_setup (struct GNUNET_PeerIdentity source_peer,
+ uint64_t ultimate_destination_finger_value,
+ struct GNUNET_PeerIdentity best_known_destination,
struct FriendInfo *target_friend,
unsigned int trail_length,
const struct GNUNET_PeerIdentity *trail_peer_list,
- unsigned int finger_map_index)
+ unsigned int is_predecessor,
+ struct GNUNET_HashCode trail_id,
+ struct GNUNET_HashCode *intermediate_trail_id)
{
struct P2PPendingMessage *pending;
struct PeerTrailSetupMessage *tsm;
struct GNUNET_PeerIdentity *peer_list;
size_t msize;
-
- msize = sizeof (struct PeerTrailSetupMessage) +
+
+ msize = sizeof (struct PeerTrailSetupMessage) +
(trail_length * sizeof (struct GNUNET_PeerIdentity));
-
+
if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
GNUNET_break (0);
return;
}
-
+
if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
- {
+ {
GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1, GNUNET_NO);
}
-
- pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+
+ pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
- tsm = (struct PeerTrailSetupMessage *) &pending[1];
+ tsm = (struct PeerTrailSetupMessage *) &pending[1];
pending->msg = &tsm->header;
tsm->header.size = htons (msize);
tsm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP);
- memcpy (&(tsm->destination_finger), &destination_finger, sizeof (uint64_t));
- memcpy (&(tsm->source_peer), source_peer, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(tsm->current_destination), current_destination, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(tsm->current_source), current_source, sizeof (struct GNUNET_PeerIdentity));
- tsm->trail_length = htonl (trail_length);
- tsm->finger_map_index = htonl (finger_map_index);
+ 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);
+ tsm->trail_id = trail_id;
+
+ if (NULL == intermediate_trail_id)
+ memset (&tsm->intermediate_trail_id, 0, sizeof (tsm->intermediate_trail_id));
+ else
+ tsm->intermediate_trail_id = *intermediate_trail_id;
if (trail_length > 0)
{
/**
- * Construct a trail setup result message and forward it to a friend.
- * @param destination_peer Peer which will get the trail to one of its finger.
- * @param source_finger Peer to which the trail has been setup to.
+ * Construct a trail setup result message and forward it to target friend.
+ * @param querying_peer Peer which sent the trail setup request and should get
+ * the result back.
+ * @param Finger Peer to which the trail has been setup to.
* @param target_friend Friend to which this message should be forwarded.
* @param trail_length Numbers of peers in the trail.
- * @param trail_peer_list Peers which are part of the trail from source to destination.
- * @param finger_map_index Index in finger peer map
+ * @param trail_peer_list Peers which are part of the trail from q
+ * querying_peer to Finger, NOT including them.
+ * @param is_predecessor Is @a Finger predecessor to @a querying_peer
+ * @param ultimate_destination_finger_value Value to which @a finger is the closest
+ * peer.
+ * @param trail_id Unique identifier of the trail.
*/
void
-GDS_NEIGHBOURS_send_trail_setup_result (const struct GNUNET_PeerIdentity *destination_peer,
- const struct GNUNET_PeerIdentity *source_finger,
+GDS_NEIGHBOURS_send_trail_setup_result (struct GNUNET_PeerIdentity querying_peer,
+ struct GNUNET_PeerIdentity finger,
struct FriendInfo *target_friend,
unsigned int trail_length,
const struct GNUNET_PeerIdentity *trail_peer_list,
- unsigned int finger_map_index)
+ unsigned int is_predecessor,
+ uint64_t ultimate_destination_finger_value,
+ struct GNUNET_HashCode trail_id)
{
struct P2PPendingMessage *pending;
struct PeerTrailSetupResultMessage *tsrm;
struct GNUNET_PeerIdentity *peer_list;
size_t msize;
-
- msize = sizeof (struct PeerTrailSetupResultMessage) +
+
+ msize = sizeof (struct PeerTrailSetupResultMessage) +
(trail_length * sizeof (struct GNUNET_PeerIdentity));
-
+
if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
GNUNET_break (0);
return;
}
-
+
if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
- {
+ {
GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1, GNUNET_NO);
}
-
- pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
- pending->importance = 0;
+
+ pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+ pending->importance = 0;
pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
- tsrm = (struct PeerTrailSetupResultMessage *) &pending[1];
+ tsrm = (struct PeerTrailSetupResultMessage *) &pending[1];
pending->msg = &tsrm->header;
tsrm->header.size = htons (msize);
tsrm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP_RESULT);
- memcpy (&(tsrm->destination_peer), destination_peer, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(tsrm->finger_identity), source_finger, sizeof (struct GNUNET_PeerIdentity));
- tsrm->trail_length = htonl (trail_length);
- tsrm->finger_map_index = htonl (finger_map_index);
-
+ tsrm->querying_peer = querying_peer;
+ tsrm->finger_identity = finger;
+ tsrm->is_predecessor = htonl (is_predecessor);
+ tsrm->trail_id = trail_id;
+ tsrm->ulitmate_destination_finger_value =
+ GNUNET_htonll (ultimate_destination_finger_value);
peer_list = (struct GNUNET_PeerIdentity *) &tsrm[1];
if (trail_length > 0)
{
/**
- * Construct a PeerVerifySuccessor message and send it to friend.
- * @param source_peer Peer which wants to verify its successor
- * @param successor Peer which is our current successor
- * @param target_friend Friend to which this message should be forwarded.
- * @param trail_peer_list Peer which are part of trail from source to destination
- * @param trail_length Number of peers in the trail list.
+ * 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
+ * @param congested_peer Peer which sent this message as it is congested.
+ * @param is_predecessor Is source_peer looking for trail to a predecessor or not.
+ * @param trail_peer_list Trails seen so far in trail setup before getting rejected
+ * by congested_peer. This does not include @a source_peer
+ * @param trail_length Total number of peers in trail_peer_list, not including
+ * @a source_peer
+ * @param trail_id Unique identifier of this trail.
+ * @param congestion_timeout Duration given by congested peer as an estimate of
+ * how long it may remain congested.
*/
-void GDS_NEIGHBOURS_send_verify_successor(const struct GNUNET_PeerIdentity *source_peer,
- const struct GNUNET_PeerIdentity *successor,
- struct FriendInfo *target_friend,
- const struct GNUNET_PeerIdentity *trail_peer_list,
- unsigned int trail_length)
+void
+GDS_NEIGHBOURS_send_trail_rejection (struct GNUNET_PeerIdentity source_peer,
+ uint64_t ultimate_destination_finger_value,
+ struct GNUNET_PeerIdentity congested_peer,
+ unsigned int is_predecessor,
+ const struct GNUNET_PeerIdentity *trail_peer_list,
+ unsigned int trail_length,
+ struct GNUNET_HashCode trail_id,
+ struct FriendInfo *target_friend,
+ const struct GNUNET_TIME_Relative congestion_timeout)
{
- struct PeerVerifySuccessorMessage *vsm;
+ struct PeerTrailRejectionMessage *trm;
struct P2PPendingMessage *pending;
struct GNUNET_PeerIdentity *peer_list;
size_t msize;
-
- msize = sizeof (struct PeerVerifySuccessorMessage) +
+
+ msize = sizeof (struct PeerTrailRejectionMessage) +
(trail_length * sizeof (struct GNUNET_PeerIdentity));
-
+
if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
GNUNET_break (0);
return;
}
-
+
if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
- {
+ {
GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1, GNUNET_NO);
}
+
+ pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+ pending->importance = 0;
+ pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
+ trm = (struct PeerTrailRejectionMessage *)&pending[1];
+ pending->msg = &trm->header;
+ trm->header.size = htons (msize);
+ 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;
+ trm->is_predecessor = htonl (is_predecessor);
+ trm->trail_id = trail_id;
+ trm->ultimate_destination_finger_value = GNUNET_htonll (ultimate_destination_finger_value);
+
+ peer_list = (struct GNUNET_PeerIdentity *) &trm[1];
+ if (trail_length > 0)
+ {
+ memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
+ }
- pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+ /* 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);
+}
+
+
+/**
+ * Construct a verify successor message and forward it to target_friend.
+ * @param source_peer Peer which wants to verify its successor.
+ * @param successor Peer which is @a source_peer's current successor.
+ * @param trail_id Unique Identifier of trail from @a source_peer to @a successor,
+ * NOT including them.
+ * @param trail List of peers which are part of trail to reach from @a source_peer
+ * to @a successor, NOT including them.
+ * @param trail_length Total number of peers in @a trail.
+ * @param target_friend Next friend to get this message.
+ */
+void
+GDS_NEIGHBOURS_send_verify_successor_message (struct GNUNET_PeerIdentity source_peer,
+ struct GNUNET_PeerIdentity successor,
+ struct GNUNET_HashCode trail_id,
+ struct GNUNET_PeerIdentity *trail,
+ unsigned int trail_length,
+ struct FriendInfo *target_friend)
+{
+ struct PeerVerifySuccessorMessage *vsm;
+ struct P2PPendingMessage *pending;
+ struct GNUNET_PeerIdentity *peer_list;
+ size_t msize;
+
+ msize = sizeof (struct PeerVerifySuccessorMessage);
+ if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+ {
+ GNUNET_break (0);
+ return;
+ }
+
+ if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
+ {
+ GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
+ 1, GNUNET_NO);
+ }
+
+ pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
pending->importance = 0; /* FIXME */
pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
vsm = (struct PeerVerifySuccessorMessage *) &pending[1];
pending->msg = &vsm->header;
vsm->header.size = htons (msize);
vsm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_VERIFY_SUCCESSOR);
- memcpy (&(vsm->successor), successor, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(vsm->source_peer), source_peer, sizeof (struct GNUNET_PeerIdentity));
- vsm->trail_length = htonl (trail_length);
+ vsm->source_peer = source_peer;
+ vsm->successor = successor;
+ vsm->trail_id = trail_id;
if (trail_length > 0)
{
peer_list = (struct GNUNET_PeerIdentity *) &vsm[1];
- memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
+ memcpy (peer_list, trail, trail_length * sizeof (struct GNUNET_PeerIdentity));
}
-
+
/* 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);
-
}
/**
- * Construct a PeerVerifySuccessorResult message and send it to friend.
- * @param destination_peer Peer which sent verify successor message
- * @param source_successor Peer to which verify successor message was sent.
- * @param my_predecessor source_successor's predecessor.
- * @param target_friend Friend to which this message should be forwarded.
- * @param trail_peer_list Peers which are part of trail from source to destination
- * @param trail_length Number of peers in the trail list.
+ * 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_verify_successor_result (const struct GNUNET_PeerIdentity *destination_peer,
- const struct GNUNET_PeerIdentity *source_successor,
- const struct GNUNET_PeerIdentity *my_predecessor,
- struct FriendInfo *target_friend,
- const struct GNUNET_PeerIdentity *trail_peer_list,
- unsigned int trail_length)
+void
+GDS_NEIGHBOURS_send_trail_teardown (struct GNUNET_HashCode trail_id,
+ unsigned int trail_direction,
+ struct GNUNET_PeerIdentity *peer)
{
- struct PeerVerifySuccessorResultMessage *vsmr;
+ struct PeerTrailTearDownMessage *ttdm;
struct P2PPendingMessage *pending;
- struct GNUNET_PeerIdentity *peer_list;
+ struct FriendInfo *target_friend;
size_t msize;
-
- msize = sizeof (struct PeerVerifySuccessorResultMessage) +
- (trail_length * sizeof(struct GNUNET_PeerIdentity));
-
+
+ msize = sizeof (struct PeerTrailTearDownMessage);
+
if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
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"),
1, GNUNET_NO);
}
- pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+ pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
pending->importance = 0; /* FIXME */
pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
- vsmr = (struct PeerVerifySuccessorResultMessage *) &pending[1];
- pending->msg = &vsmr->header;
- vsmr->header.size = htons (msize);
- vsmr->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_VERIFY_SUCCESSOR_RESULT);
- memcpy (&(vsmr->destination_peer), destination_peer, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(vsmr->source_successor), source_successor, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(vsmr->my_predecessor), my_predecessor, sizeof (struct GNUNET_PeerIdentity));
- vsmr->trail_length = htonl (trail_length);
- if (trail_length > 0)
- {
- peer_list = (struct GNUNET_PeerIdentity *) &vsmr[1];
- memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
- }
+ ttdm = (struct PeerTrailTearDownMessage *) &pending[1];
+ pending->msg = &ttdm->header;
+ ttdm->header.size = htons (msize);
+ ttdm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_TEARDOWN);
+ ttdm->trail_id = trail_id;
+ ttdm->trail_direction = htonl (trail_direction);
+
+ /* Send the message to chosen friend. */
- /* 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);
/**
- * Construct a PeerNotifyNewSuccessor message and send it to friend.
- * @param source_peer Peer which is sending notify message to its new successor.
- * @param destination_peer Peer which is the new destination.
- * @param target_friend Next friend to pass this message to.
- * @param peer_list List of peers in the trail to reach to destination_peer.
- * @param trail_length Total number of peers in peer list
+ * Construct a verify successor result message and send it to target_friend
+ * @param querying_peer Peer which sent the verify successor message.
+ * @param source_successor Current_successor of @a querying_peer.
+ * @param current_predecessor Current predecessor of @a successor. Could be same
+ * or different from @a querying_peer.
+ * @param trail_id Unique identifier of the trail from @a querying_peer to
+ * @a successor, NOT including them.
+ * @param trail List of peers which are part of trail from @a querying_peer to
+ * @a successor, NOT including them.
+ * @param trail_length Total number of peers in @a trail
+ * @param trail_direction Direction in which we are sending the message. In this
+ * case we are sending result from @a successor to @a querying_peer.
+ * @param target_friend Next friend to get this message.
*/
-void
-GDS_NEIGHBOURS_send_notify_new_successor (const struct GNUNET_PeerIdentity *source_peer,
- const struct GNUNET_PeerIdentity *destination_peer,
- const struct GNUNET_PeerIdentity *old_successor,
- struct FriendInfo *target_friend,
- const struct GNUNET_PeerIdentity *trail_peer_list,
- unsigned int trail_length)
+void
+GDS_NEIGHBOURS_send_verify_successor_result (struct GNUNET_PeerIdentity querying_peer,
+ struct GNUNET_PeerIdentity current_successor,
+ struct GNUNET_PeerIdentity probable_successor,
+ struct GNUNET_HashCode trail_id,
+ const struct GNUNET_PeerIdentity *trail,
+ unsigned int trail_length,
+ enum GDS_ROUTING_trail_direction trail_direction,
+ struct FriendInfo *target_friend)
{
- struct PeerNotifyNewSuccessorMessage *nsm;
+ struct PeerVerifySuccessorResultMessage *vsmr;
struct P2PPendingMessage *pending;
struct GNUNET_PeerIdentity *peer_list;
size_t msize;
-
- msize = sizeof (struct PeerNotifyNewSuccessorMessage) +
+
+ msize = sizeof (struct PeerVerifySuccessorResultMessage) +
(trail_length * sizeof(struct GNUNET_PeerIdentity));
-
+
if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
GNUNET_break (0);
return;
}
-
+
if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
- {
+ {
GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1, GNUNET_NO);
}
-
- pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+
+ pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
pending->importance = 0; /* FIXME */
pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
- nsm = (struct PeerNotifyNewSuccessorMessage *) &pending[1];
- pending->msg = &nsm->header;
- nsm->header.size = htons (msize);
- nsm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_NOTIFY_NEW_SUCCESSOR);
- memcpy (&(nsm->source_peer), source_peer, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(nsm->destination_peer), destination_peer, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(nsm->old_successor), old_successor, sizeof (struct GNUNET_PeerIdentity));
- nsm->trail_length = htonl (trail_length);
-
+ vsmr = (struct PeerVerifySuccessorResultMessage *) &pending[1];
+ pending->msg = &vsmr->header;
+ vsmr->header.size = htons (msize);
+ vsmr->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_VERIFY_SUCCESSOR_RESULT);
+ vsmr->querying_peer = querying_peer;
+ vsmr->current_successor = current_successor;
+ vsmr->probable_successor = probable_successor;
+ vsmr->trail_direction = htonl (trail_direction);
+ vsmr->trail_id = trail_id;
+
if (trail_length > 0)
{
- peer_list = (struct GNUNET_PeerIdentity *) &nsm[1];
- memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
+ peer_list = (struct GNUNET_PeerIdentity *) &vsmr[1];
+ memcpy (peer_list, trail, trail_length * sizeof (struct GNUNET_PeerIdentity));
}
+
/* 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);
}
+
/**
- * Send a trail tear down message
- * @param source_peer Source of the trail.
- * @param destination_peer Destination of the trail.
- * @param discarded_trail Discarded trail from source to destination.
- * @param discarded_trail_length Total number of peers in trail_list.
- * @pararm target_peer Next peer to forward this message to.
- * @param new_first_friend The new first hop in the new trail from source to destination
- * peer.
+ * Construct a notify new successor message and send it to target_friend
+ * @param source_peer Peer which wants to notify to its new successor that it
+ * could be its predecessor.
+ * @param successor New successor of @a source_peer
+ * @param successor_trail List of peers in Trail to reach from
+ * @a source_peer to @a new_successor, NOT including
+ * the endpoints.
+ * @param successor_trail_length Total number of peers in @a new_successor_trail.
+ * @param successor_trail_id Unique identifier of @a new_successor_trail.
+ * @param target_friend Next friend to get this message.
*/
void
-GDS_NEIGHBOURS_send_trail_teardown (const struct GNUNET_PeerIdentity *source_peer,
- const struct GNUNET_PeerIdentity *destination_peer,
- const struct GNUNET_PeerIdentity *discarded_trail,
- unsigned int discarded_trail_length,
- struct FriendInfo *target_friend,
- const struct GNUNET_PeerIdentity *new_first_friend)
+GDS_NEIGHBOURS_send_notify_new_successor (struct GNUNET_PeerIdentity source_peer,
+ struct GNUNET_PeerIdentity successor,
+ const struct GNUNET_PeerIdentity *successor_trail,
+ unsigned int successor_trail_length,
+ struct GNUNET_HashCode succesor_trail_id,
+ struct FriendInfo *target_friend)
{
+ struct PeerNotifyNewSuccessorMessage *nsm;
struct P2PPendingMessage *pending;
- struct PeerTrailTearDownMessage *ttdm;
struct GNUNET_PeerIdentity *peer_list;
size_t msize;
-
- msize = sizeof (struct PeerTrailTearDownMessage) +
- (discarded_trail_length * sizeof(struct GNUNET_PeerIdentity));
-
+
+ msize = sizeof (struct PeerNotifyNewSuccessorMessage) +
+ (successor_trail_length * sizeof(struct GNUNET_PeerIdentity));
+
if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
GNUNET_break (0);
return;
}
-
+
if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
- {
+ {
GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1, GNUNET_NO);
}
-
- pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+
+ pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
pending->importance = 0; /* FIXME */
pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
- ttdm = (struct PeerTrailTearDownMessage *) &pending[1];
- pending->msg = &ttdm->header;
- ttdm->header.size = htons (msize);
- ttdm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_TEARDOWN);
- memcpy (&(ttdm->source_peer), source_peer, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(ttdm->destination_peer), destination_peer, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(ttdm->new_first_friend),new_first_friend, sizeof (struct GNUNET_PeerIdentity));
- ttdm->trail_length = htonl (discarded_trail_length);
+ nsm = (struct PeerNotifyNewSuccessorMessage *) &pending[1];
+ pending->msg = &nsm->header;
+ nsm->header.size = htons (msize);
+ nsm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_NOTIFY_NEW_SUCCESSOR);
+ nsm->new_successor = successor;
+ nsm->source_peer = source_peer;
+ nsm->trail_id = succesor_trail_id;
- if (discarded_trail_length > 0)
+ if (successor_trail_length > 0)
{
- peer_list = (struct GNUNET_PeerIdentity *) &ttdm[1];
- memcpy (peer_list, discarded_trail, discarded_trail_length * sizeof (struct GNUNET_PeerIdentity));
+ peer_list = (struct GNUNET_PeerIdentity *) &nsm[1];
+ memcpy (peer_list, successor_trail,
+ successor_trail_length * sizeof (struct GNUNET_PeerIdentity));
}
+
/* Send the message to chosen friend. */
GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
target_friend->pending_count++;
/**
- *
- * @param source_peer
- * @param destination_peer
- * @param trail
- * @param trail_length
- * @param target_friend
+ * Construct an add_trail message and send it to target_friend
+ * @param source_peer Source of the trail.
+ * @param destination_peer Destination of the trail.
+ * @param trail_id Unique identifier of the trail from
+ * @a source_peer to @a destination_peer, NOT including the endpoints.
+ * @param trail List of peers in Trail from @a source_peer to @a destination_peer,
+ * NOT including the endpoints.
+ * @param trail_length Total number of peers in @a trail.
+ * @param target_friend Next friend to get this message.
*/
void
-GDS_NEIGHBOURS_send_add_trail_message (struct GNUNET_PeerIdentity *source_peer,
- struct GNUNET_PeerIdentity *destination_peer,
- struct GNUNET_PeerIdentity *trail,
- unsigned int trail_length,
- struct FriendInfo *target_friend)
+GDS_NEIGHBOURS_send_add_trail (struct GNUNET_PeerIdentity source_peer,
+ struct GNUNET_PeerIdentity destination_peer,
+ struct GNUNET_HashCode trail_id,
+ const struct GNUNET_PeerIdentity *trail,
+ unsigned int trail_length,
+ struct FriendInfo *target_friend)
{
- struct P2PPendingMessage *pending;
struct PeerAddTrailMessage *adm;
struct GNUNET_PeerIdentity *peer_list;
+ struct P2PPendingMessage *pending;
size_t msize;
-
- msize = sizeof (struct PeerAddTrailMessage) +
+
+ msize = sizeof (struct PeerAddTrailMessage) +
(trail_length * sizeof(struct GNUNET_PeerIdentity));
-
+
if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
GNUNET_break (0);
return;
}
-
+
if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
- {
+ {
GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1, GNUNET_NO);
}
-
- pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+
+ pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
pending->importance = 0; /* FIXME */
pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
adm = (struct PeerAddTrailMessage *) &pending[1];
pending->msg = &adm->header;
adm->header.size = htons (msize);
adm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_ADD_TRAIL);
- memcpy (&(adm->source_peer), source_peer, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(adm->destination_peer), destination_peer, sizeof (struct GNUNET_PeerIdentity));
- adm->trail_length = htonl (trail_length);
-
- if (trail_length > 0)
- {
- peer_list = (struct GNUNET_PeerIdentity *)&adm[1];
- memcpy (peer_list, trail, sizeof (struct GNUNET_PeerIdentity) * trail_length);
- }
-
+ adm->source_peer = source_peer;
+ adm->destination_peer = destination_peer;
+ adm->trail_id = trail_id;
+
+ 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);
target_friend->pending_count++;
process_friend_queue (target_friend);
+
}
/**
- * FIXME: CONGESTION: check the code once basic code is all correct. s
- * FIXME: call GNUNET_CONTAINER_multipeermap_iterator_destroy (iter);
- * In case the friend chosen in select_random_friend() is congested or
- * has crossed trail_threshold, then get next friend which is not congested or
- * has not crossed trail threshold from friend peermap.
- * @param current_index Index in finger peermap chosen randomly
- * @param friend_peermap_size Total number of entries in friend peermap.
- * @param count Total number of time this function has been called, in case
- * count == sizeof(friend_peermap) - 1, it means none of the friends are free.
- * @return Friend Friend found.
- * NULL in case all the friends are congested or have crossed trail threshold.
+ * Construct a trail compression message and send it to target_friend.
+ * @param source_peer Source of the 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.
*/
-static struct FriendInfo *
-get_next_friend (unsigned int current_index,
- unsigned int friend_peermap_size,
- unsigned int count)
+void
+GDS_NEIGHBOURS_send_trail_compression (struct GNUNET_PeerIdentity source_peer,
+ struct GNUNET_HashCode trail_id,
+ struct GNUNET_PeerIdentity first_friend,
+ struct FriendInfo *target_friend)
{
- struct GNUNET_CONTAINER_MultiPeerMapIterator *iter;
- struct GNUNET_PeerIdentity key_ret;
- struct FriendInfo *friend;
- int j = 0;
-
- current_index = (current_index + 1) % friend_peermap_size;
- iter = GNUNET_CONTAINER_multipeermap_iterator_create (friend_peermap);
- while(j < (current_index))
+ struct P2PPendingMessage *pending;
+ struct PeerTrailCompressionMessage *tcm;
+ size_t msize;
+
+ msize = sizeof (struct PeerTrailCompressionMessage);
+
+ if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
- if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next (iter,NULL,NULL))
- {
- j++;
- }
- else
- return NULL;
- }
+ GNUNET_break (0);
+ return;
+ }
- if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next (iter,&key_ret,(const void **)&friend))
+ if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
{
- if ((friend->trails_count > TRAIL_THROUGH_FRIEND_THRESHOLD) ||
- (0 != GNUNET_TIME_absolute_get_remaining (friend->congestion_duration).rel_value_us))
- {
- count++;
- if (count == (friend_peermap_size -1))
- return NULL;
- else
- return get_next_friend (j,friend_peermap_size,count);
- }
- return friend;
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop ("# P2P messages dropped due to full queue"),
+ 1, GNUNET_NO);
}
- else
- return NULL;
-}
+ pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+ pending->importance = 0; /* FIXME */
+ pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
+ tcm = (struct PeerTrailCompressionMessage *) &pending[1];
+ pending->msg = &tcm->header;
+ tcm->header.size = htons (msize);
+ tcm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_COMPRESSION);
+ tcm->source_peer = source_peer;
+ tcm->new_first_friend = first_friend;
+ tcm->trail_id = trail_id;
-/**
- * FIXME: CONGESTION: check the code once basic code is all correct.
- * FIXME: call GNUNET_CONTAINER_multipeermap_iterator_destroy (iter);
- * Randomly choose one of your friends from the friends_peer map
- * @return Friend Randomly chosen friend.
- * NULL in case friend peermap is empty, or all the friends are either
- * congested or have crossed trail threshold.
- */
-static struct FriendInfo *
-select_random_friend ()
-{
- unsigned int current_size;
- unsigned int *index;
- unsigned int j = 0;
- struct GNUNET_CONTAINER_MultiPeerMapIterator *iter;
- struct GNUNET_PeerIdentity key_ret;
- struct FriendInfo *friend;
-
- current_size = GNUNET_CONTAINER_multipeermap_size (friend_peermap);
- if (0 == current_size)
- return NULL;
-
- index = GNUNET_CRYPTO_random_permute (GNUNET_CRYPTO_QUALITY_WEAK, current_size);
- iter = GNUNET_CONTAINER_multipeermap_iterator_create (friend_peermap);
-
- while(j < (*index))
- {
- if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next (iter,NULL,NULL))
- {
- j++;
- }
- else
- {
- return NULL;
- }
- }
+ GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
+ target_friend->pending_count++;
+ process_friend_queue (target_friend);
- if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next (iter,&key_ret,(const void **)&friend))
- {
- if ((TRAIL_THROUGH_FRIEND_THRESHOLD == friend->trails_count) ||
- (0 != GNUNET_TIME_absolute_get_remaining (friend->congestion_duration).rel_value_us))
- {
- return get_next_friend (*index, current_size, 1);
- }
- return friend;
- }
- else
- return NULL;
}
/**
- * Compute finger_identity to which we want to setup the trail
- * @return finger_identity
+ * Search my location in trail.
+ * @param trail List of peers
+ * @return my_index if found
+ * -1 if no entry found.
*/
-static uint64_t
-compute_finger_identity()
+static int
+search_my_index (const struct GNUNET_PeerIdentity *trail,
+ int trail_length)
{
- uint64_t my_id64 ;
+ int i;
- 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));
-}
+ for (i = 0; i < trail_length; i++)
+ {
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &trail[i]))
+ return i;
+ }
+ return -1;
+}
/**
- * Compute immediate predecessor identity in the network.
- * @return peer identity of immediate predecessor.
+ * Check if the friend is congested or have reached maximum number of trails
+ * it can be part of of.
+ * @param friend Friend to be chechked.
+ * @return #GNUNET_YES if friend is not congested or have not crossed threshold.
+ * #GNUNET_NO if friend is either congested or have crossed threshold
*/
-static uint64_t
-compute_predecessor_identity()
+static int
+is_friend_congested (struct FriendInfo *friend)
{
- uint64_t my_id64;
-
- memcpy (&my_id64, &my_identity, sizeof (uint64_t));
- my_id64 = GNUNET_ntohll (my_id64);
- return (my_id64 -1);
+ if ((friend->trails_count == TRAILS_THROUGH_FRIEND_THRESHOLD)||
+ ((0 != GNUNET_TIME_absolute_get_remaining
+ (friend->congestion_timestamp).rel_value_us)))
+ return GNUNET_YES;
+ else
+ return GNUNET_NO;
}
/**
- * Ping your successor to verify if it is still your successor or not.
+ * FIXME: here we should also check if iterator is null or not. It can be NULL
+ * only if we insert randomly at locations. But as we are using trails_count
+ * as the parameter, it should not happen.
+ * Iterate over the list of all the trails of a finger. In case the first
+ * friend to reach the finger has reached trail threshold or is congested,
+ * then don't select it. In case there multiple available good trails to reach
+ * to Finger, choose the one with shortest trail length.
+ * Note: We use length as parameter. But we can use any other suitable parameter
+ * also.
+ * @param finger Finger
+ * @return struct Selected_Finger_Trail which contains the first friend , trail id
+ * and trail length. NULL in case none of the trails are free.
*/
-static void
-send_verify_successor_message()
+static struct Selected_Finger_Trail *
+select_finger_trail (struct FingerInfo *finger)
{
- struct GNUNET_CONTAINER_MultiPeerMapIterator *finger_iter;
- struct GNUNET_PeerIdentity key_ret;
- struct FriendInfo *target_friend;
- struct GNUNET_PeerIdentity next_hop;
- struct GNUNET_PeerIdentity *peer_list;
- struct FingerInfo *finger;
- unsigned int finger_index;
- int flag = 0;
+ struct FriendInfo *friend;
+ struct Trail *iterator;
+ struct Selected_Finger_Trail *finger_trail;
+ unsigned int i;
+
+ finger_trail = GNUNET_new (struct Selected_Finger_Trail);
- /* Find the successor from the finger peermap.*/
- finger_iter = GNUNET_CONTAINER_multipeermap_iterator_create (finger_peermap);
- for (finger_index = 0; finger_index < GNUNET_CONTAINER_multipeermap_size (finger_peermap); finger_index++)
+ for (i = 0; i < finger->trails_count; i++)
{
- if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next (finger_iter, &key_ret,
- (const void **)&finger))
+ iterator = &finger->trail_list[i];
+ friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &iterator->trail_head->peer);
+ if (GNUNET_YES == is_friend_congested (friend))
+ continue;
+
+ /* Check if the trail length of this trail is least seen so far. If yes then
+ set finger_trail to this trail.*/
+ if (finger_trail->trail_length > iterator->trail_length)
{
- if (0 == finger->finger_map_index)
- {
- flag = 1;
- break;
- }
+ finger_trail->friend = *friend;
+ finger_trail->trail_id = iterator->trail_id;
+ finger_trail->trail_length = iterator->trail_length;
}
}
- GNUNET_CONTAINER_multipeermap_iterator_destroy (finger_iter);
-
- /* Either you don't have a successor or you are your own successor, then don't
- send a successor message. */
- if(( flag == 0) ||
- (0 == GNUNET_CRYPTO_cmp_peer_identity(&my_identity, &(finger->finger_identity))))
- {
- return;
- }
- if (finger->first_trail_length > 0)
- {
- struct TrailPeerList *iterate;
- int i = 0;
- peer_list = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity) * finger->first_trail_length);
- iterate = finger->first_trail_head;
-
- while ( i < (finger->first_trail_length))
- {
- memcpy (&peer_list[i], &(iterate->peer), sizeof (struct GNUNET_PeerIdentity));
- iterate = iterate->next;
- i++;
- }
- memcpy (&next_hop, &peer_list[0], sizeof (struct GNUNET_PeerIdentity));
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
- }
- else
- {
- /* If trail length = 0, then our successor is our friend. */
- peer_list = NULL;
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &(finger->finger_identity));
- }
-
- GDS_NEIGHBOURS_send_verify_successor (&my_identity,
- &(finger->finger_identity),
- target_friend,
- peer_list,
- finger->first_trail_length);
+ /* No trail found. */
+ if (i == finger->trails_count)
+ finger_trail = NULL;
+
+ return finger_trail;
}
/**
- * Choose a random friend and start looking for the trail to reach to
- * finger identity through this random friend.
- *
- * @param cls closure for this task
- * @param tc the context under which the task is running
+ * FIXME; not handling the wrap around logic correctly.
+ * Select closest finger to value.
+ * @param peer1 First peer
+ * @param peer2 Second peer
+ * @param value Value to be compare
+ * @return Closest peer
*/
-static void
-send_find_finger_trail_message (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
+static struct GNUNET_PeerIdentity *
+select_closest_finger (struct GNUNET_PeerIdentity *peer1,
+ struct GNUNET_PeerIdentity *peer2,
+ uint64_t value)
{
- struct FriendInfo *target_friend;
- struct GNUNET_TIME_Relative next_send_time;
- uint64_t finger_identity;
- unsigned int finger_map_index;
-
- next_send_time.rel_value_us =
- DHT_FIND_FINGER_TRAIL_INTERVAL.rel_value_us +
- GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK,
- DHT_FIND_FINGER_TRAIL_INTERVAL.rel_value_us);
- find_finger_trail_task =
- GNUNET_SCHEDULER_add_delayed (next_send_time, &send_find_finger_trail_message,
- NULL);
+ uint64_t peer1_value;
+ uint64_t peer2_value;
- target_friend = select_random_friend ();
- if (NULL == target_friend)
+ memcpy (&peer1_value, peer1, sizeof (uint64_t));
+ memcpy (&peer2_value, peer2, sizeof (uint64_t));
+ if (peer1_value == value)
{
- return;
+ return peer1;
}
- if (PREDECESSOR_FINGER_ID == current_search_finger_index)
+ if (peer2_value == value)
{
- finger_identity = compute_predecessor_identity();
+ return peer2;
}
- else
+
+ if (peer2_value < peer1_value)
{
- finger_identity = compute_finger_identity();
- }
-
- finger_map_index = current_search_finger_index;
- GDS_NEIGHBOURS_send_trail_setup (&my_identity, finger_identity, &(target_friend->id),
- &my_identity, target_friend, 0, NULL, finger_map_index);
-}
-
-
-/**
- * Scan the trail to check if any of my own friend is part of trail. If yes
- * then shortcut the trail, send a trail teardown for the discarded trail,
- * update trail list and trail_length.
- * @param trail[Out] Current trail to reach to @a finger, will be updated
- * in case we compress the trail.
- * @param trail_length[Out] Number of peers in @a finger_trail, will be updated
- * in case we compress the trail.
- * @param finger Finger identity
- */
-static void
-scan_and_compress_trail (struct GNUNET_PeerIdentity *trail,
- unsigned int *trail_length,
- const struct GNUNET_PeerIdentity *finger)
-{
- int i;
- struct FriendInfo *target_friend;
+ 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 (0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity,finger))
- {
- /* Here you don't send a trail teardown as no one added this in their
- routing table. */
- *trail_length = 0;
- trail = NULL;
- return;
- }
- if (GNUNET_CONTAINER_multipeermap_get (friend_peermap, finger))
- {
- int discarded_trail_length = *trail_length;
- target_friend = GNUNET_CONTAINER_multipeermap_get(friend_peermap, &trail[0]);
- GDS_NEIGHBOURS_send_trail_teardown (&my_identity, finger, trail,
- discarded_trail_length, target_friend, finger);
- *trail_length = 0;
- trail = NULL;
- return;
- }
-
- i = *trail_length - 1;
-
- while (i > 1)
+ if (peer1_value < peer2_value)
{
- if (NULL == GNUNET_CONTAINER_multipeermap_get (friend_peermap, &trail[i]))
+ if ((peer1_value < value) && (value < peer2_value))
{
- /* This element of trail is not my friend. */
- i--;
+ return peer2;
}
- else
+ else if (((peer2_value < value) && (value < PEER_IDENTITES_WRAP_AROUND)) ||
+ ((0 < value) && (value < peer1_value)))
{
- /* A --> B(friend 1) --> C(friend 2)--> D ---> E, then we can rewrite the trail as
- * C --> D --> E,
- * Now, we should remove the entry from A's routing table, B's routing table
- * and update the entry in C's routing table. Rest everything will be same.
- * C's routing table should have source peer as the prev.hop.
- */
- struct GNUNET_PeerIdentity *discarded_trail;
- struct FriendInfo *target_friend;
- int discarded_trail_length;
- int j = 0;
-
- discarded_trail_length = i - 1;
- discarded_trail = GNUNET_malloc (discarded_trail_length * sizeof (struct GNUNET_PeerIdentity));
- memcpy (discarded_trail, trail, discarded_trail_length * sizeof (struct GNUNET_PeerIdentity));
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &trail[0]);
- GDS_NEIGHBOURS_send_trail_teardown (&my_identity, finger, discarded_trail,
- discarded_trail_length, target_friend,
- &trail[i]);
-
- /* Copy the trail from index i to index trail_length -1 and change
- trail length and return */
- while (i < *trail_length)
- {
- memcpy (&trail[j], &trail[i], sizeof(struct GNUNET_PeerIdentity));
- j++;
- i++;
- }
- *trail_length = j+1;
- return;
+ return peer1;
}
}
- return;
+ return NULL;
}
-/**
- * FIXME: Adapt the code for List of trails.
- * Free finger and its trail.
- * @param finger Finger to be freed.
+/**
+ * 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
+ * @param value Value to be compare
+ * @return Closest peer
*/
-static void
-free_finger (struct FingerInfo *finger)
+static struct GNUNET_PeerIdentity *
+select_closest_predecessor (struct GNUNET_PeerIdentity *peer1,
+ struct GNUNET_PeerIdentity *peer2,
+ uint64_t value)
{
- struct TrailPeerList *peer;
-
- if(finger->first_trail_head != NULL)
+ 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)
+ return peer1;
+
+ if (peer2_value == value)
+ return peer2;
+
+ if (peer1_value < peer2_value)
{
- while (NULL != (peer = finger->first_trail_head))
- {
- GNUNET_CONTAINER_DLL_remove (finger->first_trail_head, finger->first_trail_tail, peer);
- GNUNET_free (peer);
- }
+ 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 (finger->second_trail_head != NULL)
+ if (peer2_value < peer1_value)
{
- while (NULL != (peer = finger->second_trail_head))
- {
- GNUNET_CONTAINER_DLL_remove (finger->second_trail_head, finger->second_trail_tail, peer);
- GNUNET_free (peer);
- }
- GNUNET_free (finger);
+ 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.
+
+ */
/**
- * FIXME: First check if both the trails are present if yes then send it
- * for both of them. Currently sending it only for one trail.
- * Send a trail teardown message for the trail of removed finger from the finger
- * peermap.
- * @param existing_finger Finger to removed from the finger peermap.
+ * Select the closest peer among two peers (which should not be same)
+ * 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_table_index Index in finger map. If equal to PREDECESSOR_FINGER_ID,
+ * then we use different logic than other
+ * finger_table_index
+ * @return Closest peer among two peers.
*/
-static
-void send_trail_teardown (struct FingerInfo *removed_finger)
+static struct GNUNET_PeerIdentity *
+select_closest_peer (struct GNUNET_PeerIdentity *peer1,
+ struct GNUNET_PeerIdentity *peer2,
+ uint64_t value,
+ unsigned int finger_table_index)
{
- struct GNUNET_PeerIdentity *peer_list;
- struct FriendInfo *friend;
- struct TrailPeerList *finger_trail;
- int removed_finger_trail_length = removed_finger->first_trail_length;
- int i = 0;
+ struct GNUNET_PeerIdentity *closest_peer;
+ /* 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);
- if (removed_finger->first_trail_length == 0)
- return;
-
- finger_trail = removed_finger->first_trail_head;
- friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &(finger_trail->peer));
- peer_list = GNUNET_malloc ( removed_finger_trail_length * sizeof (struct GNUNET_PeerIdentity));
- while (i < removed_finger->first_trail_length)
- {
- memcpy (&peer_list[i], &(finger_trail->peer), sizeof (struct GNUNET_PeerIdentity));
- finger_trail = finger_trail->next;
- i++;
- }
-
- GDS_NEIGHBOURS_send_trail_teardown (&my_identity, &(removed_finger->finger_identity),
- peer_list, removed_finger_trail_length, friend,
- &(removed_finger->finger_identity));
+ return closest_peer;
}
/**
- * FIXME: How do we understand which is the correct trail head?
- * Add a new trail to reach an existing finger in finger peermap and increment
- * the count of number of trails to reach to this finger.
- * @param existing_finger Finger
- * @param trail New trail to be added
- * @param trail_length Total number of peers in the trail.
+ * 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
-void add_new_trail (struct FingerInfo *existing_finger,
- struct GNUNET_PeerIdentity *trail,
- unsigned int trail_length)
+static struct Closest_Peer *
+compare_finger_and_current_successor (struct Closest_Peer *current_closest_peer)
{
+ struct FingerInfo *finger;
+ struct FriendInfo *friend;
+ struct GNUNET_PeerIdentity *closest_peer;
int i;
- i = 0;
- /* FIXME: Here you need to understand which trail is there and which not.
- In case first_trail_head != NULL, then that trail is present
- so you should add the second one. Need to verify this logic. */
- if (existing_finger->first_trail_head != NULL)
+
+ for (i = 0; i < MAX_FINGERS; i++)
{
- while (i < trail_length)
- {
- struct TrailPeerList *element;
- element = GNUNET_malloc (sizeof (struct TrailPeerList));
- element->next = NULL;
- element->prev = NULL;
+ struct Selected_Finger_Trail *finger_trail;
+ finger = &finger_table[i];
- memcpy (&(element->peer), &trail[i], sizeof(struct GNUNET_PeerIdentity));
- GNUNET_CONTAINER_DLL_insert_tail(existing_finger->second_trail_head, existing_finger->second_trail_tail, element);
- i++;
- }
- }
- else if (existing_finger->second_trail_head != NULL)
- {
- while (i < trail_length)
- {
- struct TrailPeerList *element;
- element = GNUNET_malloc (sizeof (struct TrailPeerList));
- element->next = NULL;
- element->prev = NULL;
+ if (GNUNET_NO == finger->is_present)
+ continue;
- memcpy (&(element->peer), &trail[i], sizeof(struct GNUNET_PeerIdentity));
- GNUNET_CONTAINER_DLL_insert_tail(existing_finger->first_trail_head, existing_finger->first_trail_tail, element);
- i++;
- }
- }
- existing_finger->trail_count++;
-}
-
-
-/**
- * In case there are already maximum number of possible trail to reach to a finger,
- * then check if the new trail's length is lesser than any of the existing trails.
- * If yes then replace that old trail by new trail.
- * Note: Here we are taking length as a parameter to choose the best possible trail,
- * but there could be other parameters also like - 1. duration of existence of a
- * trail - older the better. 2. if the new trail is completely disjoint than the
- * other trails, then may be choosing it is better.
- * @param existing_finger
- * @param trail
- * @param trail_length
- * @return #GNUNET_YES
- * #GNUNET_NO
- */
-static
-void select_and_replace_trail (struct FingerInfo *existing_finger,
- struct GNUNET_PeerIdentity *new_trail,
- unsigned int new_trail_length)
-{
- if (existing_finger->first_trail_length == existing_finger->second_trail_length)
- {
- if (new_trail_length < existing_finger->first_trail_length)
+ /* 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))
+ continue;
+
+ /* If finger is friend. */
+ if (NULL != (friend = GNUNET_CONTAINER_multipeermap_get
+ (friend_peermap, &finger->finger_identity)))
{
- /* Randomly choose one of the trail. FIXME:currently I am just replacing the
- first trail.*/
- struct TrailPeerList *peer;
- int i = 0;
-
- while (NULL != (peer = existing_finger->first_trail_head))
- {
- GNUNET_CONTAINER_DLL_remove (existing_finger->first_trail_head, existing_finger->first_trail_tail, peer);
- GNUNET_free (peer);
- }
-
- while (i < new_trail_length)
+ 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))
{
- struct TrailPeerList *element;
- element = GNUNET_malloc (sizeof (struct TrailPeerList));
- element->next = NULL;
- element->prev = NULL;
-
- memcpy (&(element->peer), &new_trail[i], sizeof(struct GNUNET_PeerIdentity));
- GNUNET_CONTAINER_DLL_insert_tail(existing_finger->second_trail_head, existing_finger->second_trail_tail, element);
- i++;
+ current_closest_peer->best_known_destination = finger->finger_identity;
+ current_closest_peer->next_hop = finger->finger_identity;
}
+ continue;
}
- }
- else if ((new_trail_length < existing_finger->second_trail_length) &&
- (existing_finger->second_trail_length < existing_finger->first_trail_length))
- {
- /* Replace the first trail by the new trail. */
- struct TrailPeerList *peer;
- int i = 0;
-
- while (NULL != (peer = existing_finger->first_trail_head))
- {
- GNUNET_CONTAINER_DLL_remove (existing_finger->first_trail_head, existing_finger->first_trail_tail, peer);
- GNUNET_free (peer);
- }
-
- while (i < new_trail_length)
- {
- struct TrailPeerList *element;
- element = GNUNET_malloc (sizeof (struct TrailPeerList));
- element->next = NULL;
- element->prev = NULL;
- memcpy (&(element->peer), &new_trail[i], sizeof(struct GNUNET_PeerIdentity));
- GNUNET_CONTAINER_DLL_insert_tail(existing_finger->second_trail_head, existing_finger->second_trail_tail, element);
- i++;
- }
- }
- else if ( (new_trail_length < existing_finger->first_trail_length) &&
- (existing_finger->first_trail_length < existing_finger->second_trail_length))
- {
- /* Replace the second trail by the new trail. */
- struct TrailPeerList *peer;
- int i = 0;
-
- while (NULL != (peer = existing_finger->second_trail_head))
- {
- GNUNET_CONTAINER_DLL_remove (existing_finger->second_trail_head, existing_finger->second_trail_tail, peer);
- GNUNET_free (peer);
- }
-
- while (i < new_trail_length)
- {
- struct TrailPeerList *element;
- element = GNUNET_malloc (sizeof (struct TrailPeerList));
- element->next = NULL;
- element->prev = NULL;
+ /* Choose one of the trail to reach to finger. */
+ finger_trail = select_finger_trail (finger);
+
+ /* In case no trail found, ignore this finger. */
+ if (NULL == finger_trail)
+ continue;
- memcpy (&(element->peer), &new_trail[i], sizeof(struct GNUNET_PeerIdentity));
- GNUNET_CONTAINER_DLL_insert_tail(existing_finger->second_trail_head, existing_finger->second_trail_tail, element);
- i++;
+ 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;
}
/**
- * FIXME: If we remove a finger which is our friend, then how should we handle it.
- * Ideally only in case if the trail_length > 0,we increment the trail count
- * of the first friend in the trail to reach to the finger. in case finger is
- * our friend then trail length = 0, and hence, we have never incremented the
- * trail count associated with that friend.
- * Decrement the trail count for the first friend to reach to the finger.
- * @param finger
+ * 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 void
-decrement_friend_trail_count (struct FingerInfo *finger)
+static int
+compare_friend_and_current_closest_peer (void *cls,
+ const struct GNUNET_PeerIdentity *key,
+ void *value)
{
- struct FriendInfo *first_trail_friend;
- struct FriendInfo *second_trail_friend;
+ struct FriendInfo *friend = value;
+ struct Closest_Peer *current_closest_peer = cls;
+ struct GNUNET_PeerIdentity *closest_peer;
- if(finger->first_trail_head != NULL)
- {
- first_trail_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &(finger->first_trail_head->peer));
- first_trail_friend->trails_count--;
- }
-
- if(finger->second_trail_head != NULL)
- {
- second_trail_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
- &(finger->second_trail_head->peer));
- second_trail_friend->trails_count--;
- }
+ if (GNUNET_YES == is_friend_congested (friend))
+ return GNUNET_YES;
-#if 0
- /* We will not need this variable any more, all_friends_trail_threshold,
- FIXME: REMOVE IT. */
- if (GNUNET_YES == all_friends_trail_threshold)
+ 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))
{
- all_friends_trail_threshold = GNUNET_NO;
- /* FIXME; Here you should reschedule the send_find_finger_task here. or
- make a call.*/
+ current_closest_peer->best_known_destination = friend->id;
+ current_closest_peer->next_hop = friend->id;
}
-#endif
+
+ return GNUNET_YES;
}
-
/**
- * FIXME: create a different data structure for storing the peer ids here.
- * Select the closest finger. Used for both predecessor and other fingers..
- * But internally calls different functions for predecessor and other fingers.
- * @param existing_finger Finger in finger peermap.
- * @param new_finger New finger identity
- * @param finger_map_index Index in finger peermap where @a existing_finger is stored.
- * @return #GNUNET_YES if the new finger is closest.
- * #GNUNET_NO if the old finger is closest.
- * #GNUNET_SYSERR in case our own identity is closest (should never happen).
+ * Initialize current_successor to my_identity.
+ * @param my_identity My peer identity
+ * @return current_successor
*/
-static
-int select_finger (struct FingerInfo *existing_finger,
- const struct GNUNET_PeerIdentity *new_finger,
- unsigned int finger_map_index)
+static struct Closest_Peer *
+init_current_successor (struct GNUNET_PeerIdentity my_identity,
+ uint64_t destination_finger_value,
+ unsigned int is_predecessor)
{
- struct Sorting_List peers[3]; /* 3 for existing_finger, new_finger, my_identity */
- struct Sorting_List *closest_finger;
- uint64_t value;
- int k;
+ struct Closest_Peer *current_closest_peer;
- for (k = 0; k < 3; k++)
- peers[k].data = 0;
+ 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;
- /* Add your entry to peers. */
- memcpy (&peers[0], &my_identity, sizeof (uint64_t));
- peers[0].type = MY_ID;
- peers[0].data = NULL;
-
- /* Add existing_finger identity to the peers. */
- memcpy (&peers[1], &(existing_finger->finger_identity), sizeof (uint64_t));
- peers[1].type = FINGER;
- peers[1].data = existing_finger;
-
- /* Add new_finger identity to the peers. s*/
- memcpy (&peers[2], &new_finger, sizeof (uint64_t));
- peers[2].type = VALUE;
- peers[2].data = NULL;
-
- memcpy (&value, &my_identity, sizeof (uint64_t));
- qsort (&peers, 3, sizeof (struct Sorting_List), &compare_peer_id);
-
- if (PREDECESSOR_FINGER_ID == finger_map_index)
- closest_finger = find_closest_predecessor (peers, value, 3);
- else
- closest_finger = find_closest_successor (peers, value, 3);
-
- if (closest_finger->type == FINGER)
- {
- return GNUNET_NO;
- }
- else if (closest_finger->type == VALUE)
- {
- return GNUNET_YES;
- }
- else if (closest_finger->type == MY_ID);
- {
- return GNUNET_SYSERR;
- }
+ return current_closest_peer;
}
/**
- * FIXME: Better name, and make the code more cleaner.
- * Compare the new finger entry added and our successor.
- * @return #GNUNET_YES if same.
- * #GNUNET_NO if not.
+ * 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 int
-compare_new_entry_and_successor (const struct GNUNET_PeerIdentity *new_finger,
- int finger_map_index)
+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)
{
- int successor_flag = 0;
- struct FingerInfo *successor_finger;
- struct GNUNET_CONTAINER_MultiPeerMapIterator *finger_iter;
- int i;
+ struct Closest_Peer *current_closest_peer;
+ struct GNUNET_PeerIdentity *next_hop;
- if (PREDECESSOR_FINGER_ID == finger_map_index)
- return GNUNET_NO;
+ /* 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));
- finger_iter = GNUNET_CONTAINER_multipeermap_iterator_create (finger_peermap);
- for (i= 0; i < GNUNET_CONTAINER_multipeermap_size (finger_peermap); i++)
- {
- if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next (finger_iter, NULL,
- (const void **)&successor_finger))
- {
- if (successor_finger->finger_map_index == 0)
- {
- successor_flag = 1;
- break;
- }
- }
- }
- GNUNET_CONTAINER_multipeermap_iterator_destroy (finger_iter);
+ /* Compare each finger entry with current_successor and update current_successor
+ * with finger if its closest. */
+ compare_finger_and_current_successor (current_closest_peer);
- /* Ideally we should never reach here. */
- if (successor_flag == 0)
- {
- GNUNET_break (0);
- return GNUNET_NO;
- }
+ *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;
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (new_finger, &(successor_finger->finger_identity)))
- return GNUNET_YES;
- else
- return GNUNET_NO;
+ return next_hop;
}
/**
- * Add a new entry in finger table.
- * @param finger_identity PeerIdentity of the new finger
- * @param finger_trail Trail to reach to the finger, can be NULL in case I am my own
- * finger.
- * @param finger_trail_length Number of peers in the trail, can be 0 in case finger
- * is a friend or I am my own finger.
- * @param finger_map_index Index in finger map.
+ * Construct a Put message and send it to target_peer.
+ * @param key Key for the content
+ * @param block_type Type of the block
+ * @param options Routing options
+ * @param desired_replication_level Desired replication count
+ * @param best_known_dest Peer to which this message should reach eventually,
+ * as it is best known destination to me.
+ * @param intermediate_trail_id Trail id in case
+ * @param target_peer Peer to which this message will be forwarded.
+ * @param hop_count Number of hops traversed so far.
+ * @param put_path_length Total number of peers in @a put_path
+ * @param put_path Number of peers traversed so far
+ * @param expiration_time When does the content expire
+ * @param data Content to store
+ * @param data_size Size of content @a data in bytes
*/
-static int
-add_new_entry (const struct GNUNET_PeerIdentity *finger_identity,
- struct GNUNET_PeerIdentity *finger_trail,
- uint32_t finger_trail_length,
- uint32_t finger_map_index)
+void
+GDS_NEIGHBOURS_send_put (const struct GNUNET_HashCode *key,
+ enum GNUNET_BLOCK_Type block_type,
+ enum GNUNET_DHT_RouteOption options,
+ uint32_t desired_replication_level,
+ struct GNUNET_PeerIdentity *best_known_dest,
+ struct GNUNET_HashCode *intermediate_trail_id,
+ struct GNUNET_PeerIdentity *target_peer,
+ uint32_t hop_count,
+ uint32_t put_path_length,
+ struct GNUNET_PeerIdentity *put_path,
+ struct GNUNET_TIME_Absolute expiration_time,
+ const void *data, size_t data_size)
{
- struct FriendInfo *first_friend_trail;
- struct FingerInfo *new_finger_entry;
- int i;
+ struct PeerPutMessage *ppm;
+ 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 +
+ sizeof (struct PeerPutMessage);
- /* Add a new entry. */
- new_finger_entry = GNUNET_malloc (sizeof (struct FingerInfo));
- memcpy (&(new_finger_entry->finger_identity), finger_identity, sizeof (struct GNUNET_PeerIdentity));
- new_finger_entry->finger_map_index = finger_map_index;
- new_finger_entry->first_trail_length = finger_trail_length;
- new_finger_entry->trail_count = 1;
+ if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+ {
+ put_path_length = 0;
+ msize = data_size + sizeof (struct PeerPutMessage);
+ }
- if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity,finger_identity)) /* finger_trail is NULL in case I am my own finger identity. */
+ if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
{
- /* Incrementing the friend trails count. */
- if (finger_trail_length > 0)
- {
- first_friend_trail = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &finger_trail[0]);
- first_friend_trail->trails_count++;
- }
- else
- {
- /* It means the finger is my friend. */
- first_friend_trail = GNUNET_CONTAINER_multipeermap_get (friend_peermap, finger_identity);
- first_friend_trail->trails_count++;
- }
- new_finger_entry->first_friend_trails_count = first_friend_trail->trails_count;
+ GNUNET_break (0);
+ return;
+ }
+
+ /* This is the first call made from clients file. So, we should search for the
+ target_friend. */
+ if (NULL == target_peer)
+ {
+ uint64_t key_value;
+ struct GNUNET_PeerIdentity *next_hop;
+
+ memcpy (&key_value, key, sizeof (uint64_t));
+ local_best_known_dest = GNUNET_new (struct GNUNET_PeerIdentity);
- /* Copy the trail. */
- i = 0;
- while (i < finger_trail_length)
+ 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 (local_best_known_dest, &my_identity))
{
- struct TrailPeerList *element;
- element = GNUNET_malloc (sizeof (struct TrailPeerList));
- element->next = NULL;
- element->prev = NULL;
-
- memcpy (&(element->peer), &finger_trail[i], sizeof(struct GNUNET_PeerIdentity));
- GNUNET_CONTAINER_DLL_insert_tail(new_finger_entry->first_trail_head, new_finger_entry->first_trail_tail, element);
- i++;
+ /* I am the destination but we have already done datacache_put in client file. */
+ return;
}
- }
-
- return GNUNET_CONTAINER_multipeermap_put (finger_peermap,
- &(new_finger_entry->finger_identity),
- new_finger_entry,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
-}
-
-
-/**
- * Choose the closest finger between existing finger and new finger.
- * If the new finger is closest, then send a trail_teardown message along
- * existing_finger's trail. In case both the id's are same, and there is a place
- * to add more trails, then store both of them. In case there is no space to
- * store any more trail, then choose the best trail (best - depends on length in
- * current_implementation) and discard the others.
- * @param existing_finger
- * @param new_finger Existing finger in finger_peermap for @a finger_map_index
- * @param trail Trail to reach from me to @a new_finger
- * @param trail_length Total number of peers in @a trail.
- * @param finger_map_index Index in finger peermap.
- * @return #GNUNET_YES In case we want to store the new entry.
- * #GNUNET_NO In case we want the existing entry.
- * #GNUNET_SYSERR Error.
- */
-static
-int select_closest_finger (struct FingerInfo *existing_finger,
- const struct GNUNET_PeerIdentity *new_finger,
- struct GNUNET_PeerIdentity *trail,
- unsigned int trail_length,
- unsigned int finger_map_index)
-{
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&(existing_finger->finger_identity), new_finger))
- {
- /* New entry and existing entry are same. */
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&(existing_finger->finger_identity), &my_identity))
- {
- /* If existing_finger is my_identity then trail_length = 0, trail = NULL. In
- this case you don't need to check the trails. Exit. */
- return GNUNET_NO;
- }
- if (trail_length > 0)
- {
- scan_and_compress_trail (trail, &trail_length, new_finger);
- }
- if (existing_finger->trail_count < TRAIL_COUNT)
- {
- add_new_trail (existing_finger, trail, trail_length);
- return GNUNET_NO;
- }
- else
- {
- select_and_replace_trail (existing_finger, trail, trail_length);
- return GNUNET_NO;
- }
- }
- else if (GNUNET_YES == select_finger (existing_finger, new_finger, finger_map_index))
- {
- /* New finger is the closest finger. */
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity, new_finger))
- {
- /* FIXME: Here in case the new finger is my_identity and old entry is not,
- should we keep the old entry even if the old entry is not the closest? */
- return GNUNET_NO;
- }
- send_trail_teardown (existing_finger);
- decrement_friend_trail_count (existing_finger);
- free_finger (existing_finger);
-
- if (trail_length > 0)
- {
- scan_and_compress_trail (trail, &trail_length, new_finger);
- }
- return GNUNET_YES;
- }
- else if (GNUNET_NO == select_finger (existing_finger, new_finger,finger_map_index))
- {
- /* existing_finger is the closest finger. */
- return GNUNET_NO;
- }
- return GNUNET_SYSERR;
-}
-
-
-/**
- * Check if there is already an entry for finger map index in finger table.
- * If yes then choose the closest finger.
- * @param finger_identity Peer Identity of finger.
- * @param finger_trail Trail to reach from me to @a finger_identity
- * @param finger_trail_length Total number of peers in finger_trail.
- * @param finger_map_index Index in finger_peermap.
- * @return #GNUNET_YES if the new entry is added.
- * #GNUNET_NO if the new entry is discarded.
- */
-static
-int finger_table_add (const struct GNUNET_PeerIdentity *finger_identity,
- struct GNUNET_PeerIdentity *finger_trail,
- uint32_t finger_trail_length,
- uint32_t finger_map_index)
-{
- struct FingerInfo *existing_finger;
- struct GNUNET_CONTAINER_MultiPeerMapIterator *finger_iter;
- int i;
- int old_entry_found = GNUNET_NO;
- int new_entry_added = GNUNET_NO;
-
- /* Check if there is already an entry for the finger map index in the finger peer map. */
- finger_iter = GNUNET_CONTAINER_multipeermap_iterator_create (finger_peermap);
- for (i= 0; i < GNUNET_CONTAINER_multipeermap_size (finger_peermap); i++)
- {
- if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next (finger_iter, NULL,
- (const void **)&existing_finger))
- {
- if (existing_finger->finger_map_index == finger_map_index)
- {
- old_entry_found = GNUNET_YES;
- if ( GNUNET_NO == select_closest_finger (existing_finger, finger_identity,
- finger_trail, finger_trail_length,
- finger_map_index))
- goto update_current_search_finger_index;
- else
- break;
- }
- }
- }
- GNUNET_CONTAINER_multipeermap_iterator_destroy (finger_iter);
-
- if (GNUNET_NO == old_entry_found)
- {
- if (finger_trail_length > 0)
- {
- scan_and_compress_trail (finger_trail, &finger_trail_length, finger_identity);
- }
- }
-
- /* FIXME: handle the case when addition in peer map failed. */
- if(GNUNET_OK == add_new_entry (finger_identity,finger_trail,finger_trail_length, finger_map_index))
- new_entry_added = GNUNET_YES;
- else
- return GNUNET_NO;
-
- update_current_search_finger_index:
- if (0 == finger_map_index)
- {
- current_search_finger_index = PREDECESSOR_FINGER_ID;
- if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity,finger_identity))
- send_verify_successor_message();
- }
- else if (GNUNET_YES == compare_new_entry_and_successor (finger_identity,finger_map_index))
- {
- current_search_finger_index = 0;
- }
- else
- {
- current_search_finger_index = current_search_finger_index - 1;
- }
-
- return new_entry_added;
-}
-
-
-/**
- *
- * @param all_known_peers
- * @param array_size
- * @param friend
- * @param key_value
- * @return
- */
-static struct Sorting_List *
-get_next_successor (struct Sorting_List *all_known_peers,
- unsigned int array_size,
- struct FriendInfo *friend,
- uint64_t key_value)
-{
- /* 1. search friend in all_known_peers.
- 2. get the next peer. if peer == my_identity or peer == value, then go to
- next element.
- 3. if friend then again check if threshold crossed or not . If not then return
- or else again increment. remember starting index of friend in all_known_peers
- and when you reach to it again then return NULL as it means all the friend
- are congested or threshold reached.
- */
- return NULL;
-}
-
-
-/**
- * Check if the friend is congested or has crossed TRAIL_THRESHOLD. If yes
- * then choose the peer next to it in the array. In case number of times this
- * function is called is equal to total number of entries in the array then it
- * means that none of the friends are busy. But remember in this array you also
- * have your own identity, value that you were searching, You should skip those
- * and also keep the count = size -2. But if we call in this order is our get/put
- * not getting wrong.
- * @param all_known_peers
- * @param array_size
- * @param friend Friend to be checked if
- * @param key_value To be ignored
- * @return #GNUNET_YES
- * #GNUNET_NO
- */
-static int
-check_friend_threshold_and_congestion (struct Sorting_List *all_known_peers,
- unsigned int array_size,
- struct FriendInfo *friend,
- uint64_t key_value)
-{
- if (friend->trails_count == TRAIL_THROUGH_FRIEND_THRESHOLD)
- {
- return GNUNET_YES;
- }
- return GNUNET_NO;
-}
-
-
-/**
- * FIXME: Complete the code for checking the threshold and getting the next
- * peer, add the case in finger.
- * In case a friend is either congested or has crossed its trail threshold,
- * then don't consider it as next successor, In case of finger if its first
- * friend has crossed the threshold then don't consider it. In case no finger
- * or friend is found, then return NULL.
- * Find closest successor for the value.
- * @param value Value for which we are looking for successor
- * @param[out] current_destination set to my_identity in case I am the final destination,
- * set to friend identity in case friend is final destination,
- * set to first friend to reach to finger, in case finger
- * is final destination.
- * @param[out] current_source set to my_identity.
- * @param finger_map_index Index in finger peer map.
- * @return Peer identity of next hop to send trail setup message to,
- * NULL in case all the friends are either congested or have crossed
- * their trail threshold.
- */
-static struct GNUNET_PeerIdentity *
-find_successor (uint64_t value, struct GNUNET_PeerIdentity *current_destination,
- struct GNUNET_PeerIdentity *current_source, unsigned int finger_map_index)
-{
- struct GNUNET_CONTAINER_MultiPeerMapIterator *friend_iter;
- struct GNUNET_CONTAINER_MultiPeerMapIterator *finger_iter;
- struct GNUNET_PeerIdentity key_ret;
- struct FriendInfo *friend;
- struct FingerInfo *finger;
- unsigned int finger_index;
- unsigned int friend_index;
- struct Sorting_List *successor;
- unsigned int size;
- int j;
-
- /* 2 is added in size for my_identity and value which will part of all_known_peers. */
- size = GNUNET_CONTAINER_multipeermap_size (friend_peermap)+
- GNUNET_CONTAINER_multipeermap_size (finger_peermap)+
- 2;
-
- struct Sorting_List all_known_peers[size];
-
- int k;
- for (k = 0; k < size; k++)
- all_known_peers[k].peer_id = 0;
-
- /* Copy your identity at 0th index in all_known_peers. */
- j = 0;
- memcpy (&(all_known_peers[j].peer_id), &my_identity, sizeof (uint64_t));
- all_known_peers[j].type = MY_ID;
- all_known_peers[j].data = 0;
- j++;
-
- /* Copy value */
- all_known_peers[j].peer_id = value;
- all_known_peers[j].type = VALUE;
- all_known_peers[j].data = 0;
- j++;
-
- /* Iterate over friend peer map and copy all the elements into array. */
- friend_iter = GNUNET_CONTAINER_multipeermap_iterator_create (friend_peermap);
- for (friend_index = 0; friend_index < GNUNET_CONTAINER_multipeermap_size (friend_peermap); friend_index++)
- {
- if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next(friend_iter,&key_ret,(const void **)&friend))
- {
- memcpy (&(all_known_peers[j].peer_id), &(friend->id), sizeof (uint64_t));
- all_known_peers[j].type = FRIEND;
- all_known_peers[j].data = friend;
- j++;
- }
- }
-
-
- /* Iterate over finger map and copy all the entries into all_known_peers array. */
- finger_iter = GNUNET_CONTAINER_multipeermap_iterator_create (finger_peermap);
- for (finger_index = 0; finger_index < GNUNET_CONTAINER_multipeermap_size (finger_peermap); finger_index++)
- {
- if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next(finger_iter,&key_ret,(const void **)&finger))
- {
- memcpy (&(all_known_peers[j].peer_id), &(finger->finger_identity), sizeof (uint64_t));
- all_known_peers[j].type = FINGER;
- all_known_peers[j].data = finger;
- j++;
- }
- }
-
- GNUNET_CONTAINER_multipeermap_iterator_destroy (finger_iter);
- GNUNET_CONTAINER_multipeermap_iterator_destroy (friend_iter);
-
-
- qsort (&all_known_peers, size, sizeof (struct Sorting_List), &compare_peer_id);
-
- /* search value in all_known_peers array. */
- if (PREDECESSOR_FINGER_ID == finger_map_index)
- successor = find_closest_predecessor (all_known_peers, value, size);
- else
- successor = find_closest_successor (all_known_peers, value, size);
-
- if (successor->type == MY_ID)
- {
- memcpy (current_destination, &my_identity, sizeof (struct GNUNET_PeerIdentity));
- return &my_identity;
- }
- else if (successor->type == FRIEND)
- {
- struct FriendInfo *target_friend;
- target_friend = (struct FriendInfo *)successor->data;
- if( GNUNET_YES == check_friend_threshold_and_congestion (all_known_peers, size, target_friend, value))
- {
- get_next_successor (all_known_peers, size, friend, value);
- }
- memcpy (current_destination, &(target_friend->id), sizeof (struct GNUNET_PeerIdentity));
- memcpy (current_source, &my_identity, sizeof (struct GNUNET_PeerIdentity));
- return current_destination;
- }
- else if (successor->type == FINGER)
- {
- struct GNUNET_PeerIdentity *next_hop;
- struct FingerInfo *finger;
- finger = successor->data;
- next_hop = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
-
- if (finger->first_trail_length > 0)
- {
- struct TrailPeerList *iterator;
- iterator = GNUNET_malloc (sizeof (struct TrailPeerList));
- iterator = finger->first_trail_head;
- memcpy (next_hop, &(iterator->peer), sizeof (struct GNUNET_PeerIdentity));
- }
- else /* This means finger is our friend. */
- memcpy (next_hop, &(finger->finger_identity), sizeof(struct GNUNET_PeerIdentity));
-
- memcpy (current_destination, &(finger->finger_identity), sizeof (struct GNUNET_PeerIdentity));
- memcpy (current_source, &my_identity, sizeof (struct GNUNET_PeerIdentity));
- return next_hop;
+ else
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
}
else
{
- GNUNET_assert (0);
- return NULL;
- }
-}
-
-
-/**
- * Construct a Put message and send it to target_peer.
- * @param key Key for the content
- * @param data Content to store
- * @param data_size Size of content @a data in bytes
- * @param block_type Type of the block
- * @param options Routing options
- * @param desired_replication_level Desired replication count
- * @param expiration_time When does the content expire
- * @param current_destination
- * @param current_source
- * @param target_peer Peer to which this message will be forwarded.
- * @param hop_count Number of hops traversed so far.
- * @param put_path_length Total number of peers in @a put_path
- * @param put_path Number of peers traversed so far
- */
-void
-GDS_NEIGHBOURS_send_put (const struct GNUNET_HashCode *key,
- const void *data, size_t data_size,
- enum GNUNET_BLOCK_Type block_type,
- enum GNUNET_DHT_RouteOption options,
- uint32_t desired_replication_level,
- struct GNUNET_TIME_Absolute expiration_time,
- struct GNUNET_PeerIdentity current_destination,
- struct GNUNET_PeerIdentity current_source,
- struct GNUNET_PeerIdentity *target_peer,
- uint32_t hop_count,
- uint32_t put_path_length,
- struct GNUNET_PeerIdentity *put_path)
-{
- struct PeerPutMessage *ppm;
- struct P2PPendingMessage *pending;
- struct FriendInfo *target_friend;
- struct GNUNET_PeerIdentity *pp;
- size_t msize;
-
- msize = put_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size +
- sizeof (struct PeerPutMessage);
-
- if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
- {
- put_path_length = 0;
- msize = data_size + sizeof (struct PeerPutMessage);
- }
-
- if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
- {
- GNUNET_break (0);
- return;
- }
-
- /* This is the first call made from clients file. So, we should search for the
- target_friend. */
- if (NULL == target_peer)
- {
- uint64_t key_value;
- struct GNUNET_PeerIdentity *next_hop;
-
- memcpy (&key_value, key, sizeof (uint64_t));
- next_hop = find_successor (key_value, ¤t_destination, ¤t_source,PUT_GET_REQUEST);
- if (0 == GNUNET_CRYPTO_cmp_peer_identity(next_hop, &my_identity)) /* I am the destination do datacache_put */
- {
- GDS_DATACACHE_handle_put (expiration_time, key, put_path_length, put_path,
- block_type, data_size, data);
- return;
- }
- else
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
+ 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);
+ if (NULL == best_known_dest)
+ ppm->best_known_destination = *local_best_known_dest;
+ else
+ ppm->best_known_destination = *best_known_dest;
ppm->key = *key;
- ppm->current_destination = current_destination;
- ppm->current_source = current_source;
-
+ if (NULL == intermediate_trail_id)
+ memset (&ppm->intermediate_trail_id, 0, sizeof (ppm->intermediate_trail_id));
+ else
+ ppm->intermediate_trail_id = *intermediate_trail_id;
pp = (struct GNUNET_PeerIdentity *) &ppm[1];
if (put_path_length != 0)
{
-/**
- * Construct a Get message and send it to target_peer.
- * @param key Key for the content
+/**
+ * Construct a Get message and send it to target_peer.
+ * @param key Key for the content
* @param block_type Type of the block
* @param options Routing options
* @param desired_replication_level Desired replication count
- * @param expiration_time When does the content expire
- * @param current_destination
- * @param current_source
+ * @param best_known_dest
+ * @param intermediate_trail_id
* @param target_peer Peer to which this message will be forwarded.
* @param hop_count Number of hops traversed so far.
- * @param put_path_length Total number of peers in @a put_path
- * @param put_path Number of peers traversed so far
+ * @param data Content to store
+ * @param data_size Size of content @a data in bytes
+ * @param get_path_length Total number of peers in @a get_path
+ * @param get_path Number of peers traversed so far
*/
void
GDS_NEIGHBOURS_send_get (const struct GNUNET_HashCode *key,
enum GNUNET_BLOCK_Type block_type,
enum GNUNET_DHT_RouteOption options,
uint32_t desired_replication_level,
- struct GNUNET_PeerIdentity current_destination,
- struct GNUNET_PeerIdentity current_source,
+ struct GNUNET_PeerIdentity *best_known_dest,
+ struct GNUNET_HashCode *intermediate_trail_id,
struct GNUNET_PeerIdentity *target_peer,
uint32_t hop_count,
uint32_t get_path_length,
struct PeerGetMessage *pgm;
struct P2PPendingMessage *pending;
struct FriendInfo *target_friend;
+ struct GNUNET_PeerIdentity *local_best_known_dest;
struct GNUNET_PeerIdentity *gp;
size_t msize;
if (NULL == target_peer)
{
- /* This is the first call from client file, we need to search for next_hop*/
struct GNUNET_PeerIdentity *next_hop;
uint64_t key_value;
memcpy (&key_value, key, sizeof (uint64_t));
// FIXME: endianess of key_value!?
- next_hop = find_successor (key_value, ¤t_destination, ¤t_source,PUT_GET_REQUEST);
- if (0 == GNUNET_CRYPTO_cmp_peer_identity(&my_identity,next_hop)) /* I am the destination do datacache_put */
+ 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))
{
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->current_destination = current_destination;
- pgm->current_source = current_source;
+ 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)
/**
* Send the get result to requesting client.
- * @param expiration When will this result expire?
* @param key Key of the requested data.
+ * @param type Block type
+ * @param target_peer Next peer to forward the message to.
+ * @param source_peer Peer which has the data for the key.
* @param put_path_length Number of peers in @a put_path
* @param put_path Path taken to put the data at its stored location.
- * @param type Block type
- * @param data_size Size of the @a data
- * @param data Payload to store
- * @param get_path Path taken to reach to the location of the key.
* @param get_path_length Number of peers in @a get_path
- * @param next_hop Next peer to forward the message to.
- * @param source_peer Peer which has the data for the key.
+ * @param get_path Path taken to reach to the location of the key.
+ * @param expiration When will this result expire?
+ * @param data Payload to store
+ * @param data_size Size of the @a data
*/
-void
-GDS_NEIGHBOURS_send_get_result (struct GNUNET_TIME_Absolute expiration,
- const struct GNUNET_HashCode *key,
+void
+GDS_NEIGHBOURS_send_get_result (const struct GNUNET_HashCode *key,
+ enum GNUNET_BLOCK_Type type,
+ struct GNUNET_PeerIdentity *target_peer,
+ struct GNUNET_PeerIdentity *source_peer,
unsigned int put_path_length,
const struct GNUNET_PeerIdentity *put_path,
- enum GNUNET_BLOCK_Type type, size_t data_size,
- const void *data,
- struct GNUNET_PeerIdentity *get_path,
unsigned int get_path_length,
- struct GNUNET_PeerIdentity *next_hop,
- struct GNUNET_PeerIdentity *source_peer)
+ struct GNUNET_PeerIdentity *get_path,
+ struct GNUNET_TIME_Absolute expiration,
+ const void *data, size_t data_size)
{
struct PeerGetResultMessage *get_result;
struct GNUNET_PeerIdentity *get_result_path;
struct FriendInfo *target_friend;
int current_path_index;
size_t msize;
-
+
msize = get_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size +
sizeof (struct PeerPutMessage);
current_path_index = search_my_index(get_path, get_path_length);
if (GNUNET_SYSERR == current_path_index)
{
- /* FIXME: This assertion always fails. FIX IT. */
GNUNET_break (0);
return;
}
}
if (0 == current_path_index)
{
- GDS_CLIENTS_handle_reply (expiration, key, get_path_length, get_path, put_path_length,
+ GDS_CLIENTS_handle_reply (expiration, key, get_path_length,
+ get_path, put_path_length,
put_path, type, data_size, data);
return;
}
get_result->header.size = htons (msize);
get_result->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_GET_RESULT);
get_result->key = *key;
- memcpy (&(get_result->source_peer), source_peer, sizeof (struct GNUNET_PeerIdentity));
+ /* FIXME: check if you are passing the correct querying_peer as described in
+ the get_result documentation. */
+ 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? */
pp = (struct GNUNET_PeerIdentity *)&get_result_path[1];
memcpy (pp, put_path,sizeof (struct GNUNET_PeerIdentity) * put_path_length);
}
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
+
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &get_result_path[current_path_index - 1]);
GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
target_friend->pending_count++;
process_friend_queue (target_friend);
/**
- * Send trail rejection message to the peer which sent me a trail setup message.
- * @param source_peer Source peer which wants to set up the trail.
- * @param finger_identity Value whose successor will be the finger of @a source_peer.
- * @param congested_peer Peer which has send trail rejection message.
- * @param next_hop Peer to which this message should be forwarded.
- * @param finger_map_index Index in @a source_peer finger peermap.
- * @param trail_peer_list Trail followed to reach from @a source_peer to next_hop,
- * NULL, in case the @a congested_peer was the first peer
- * to which trail setup message was forwarded.
- * @param trail_length Number of peers in trail_peer_list.
+ * Randomly choose one of your friends (which is not congested and have not crossed
+ * trail threshold) from the friends_peer map
+ * @return Friend Randomly chosen friend.
+ * NULL in case friend peermap is empty, or all the friends are either
+ * congested or have crossed trail threshold.
*/
-void
-GDS_NEIGHBOURS_send_trail_rejection (const struct GNUNET_PeerIdentity *source_peer,
- uint64_t finger_identity,
- const struct GNUNET_PeerIdentity *congested_peer,
- const struct GNUNET_PeerIdentity *next_hop,
- unsigned int finger_map_index,
- struct GNUNET_PeerIdentity *trail_peer_list,
- unsigned int trail_length)
+static struct FriendInfo *
+select_random_friend ()
{
- struct PeerTrailRejectionMessage *trail_rejection;
- struct GNUNET_PeerIdentity *trail_list;
- struct P2PPendingMessage *pending;
- struct FriendInfo *target_friend;
- size_t msize;
-
- msize = trail_length * sizeof(struct GNUNET_PeerIdentity) +
- sizeof (struct PeerTrailRejectionMessage);
-
- if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
- {
- GNUNET_break (0);
- return;
- }
-
- pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
- pending->importance = 0;
- pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
- trail_rejection = (struct PeerTrailRejectionMessage *) &pending[1];
- pending->msg = &trail_rejection->header;
- trail_rejection->header.size = htons (msize);
- trail_rejection->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP);
- memcpy (&(trail_rejection->source_peer), source_peer, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(trail_rejection->congested_peer), congested_peer, sizeof (struct GNUNET_PeerIdentity));
- memcpy (&(trail_rejection->finger_identity_value), &finger_identity, sizeof (uint64_t));
- trail_rejection->finger_map_index = htonl (finger_map_index);
- trail_rejection->trail_length = htonl (trail_length);
-
- if (trail_length != 0)
+ unsigned int current_size;
+ uint32_t index;
+ unsigned int j = 0;
+ struct GNUNET_CONTAINER_MultiPeerMapIterator *iter;
+ struct GNUNET_PeerIdentity key_ret;
+ struct FriendInfo *friend;
+
+ current_size = GNUNET_CONTAINER_multipeermap_size (friend_peermap);
+ if (0 == current_size)
+ return NULL;
+
+ index = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, current_size);
+ iter = GNUNET_CONTAINER_multipeermap_iterator_create (friend_peermap);
+
+ for (j = 0; j < index ; j++)
+ GNUNET_assert (GNUNET_YES ==
+ GNUNET_CONTAINER_multipeermap_iterator_next (iter, NULL, NULL));
+ do
{
- trail_list = (struct GNUNET_PeerIdentity *)&trail_rejection[1];
- memcpy (trail_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
- }
-
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
- GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
- target_friend->pending_count++;
- process_friend_queue (target_friend);
+ if (j == current_size)
+ {
+ j = 0;
+ GNUNET_CONTAINER_multipeermap_iterator_destroy (iter);
+ iter = GNUNET_CONTAINER_multipeermap_iterator_create (friend_peermap);
+
+ }
+ GNUNET_assert (GNUNET_YES ==
+ GNUNET_CONTAINER_multipeermap_iterator_next (iter,
+ &key_ret,
+ (const void **)&friend));
+
+ /* 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;
+ }
+ friend = NULL;
+ j++;
+ } while (j != index);
+
+ GNUNET_CONTAINER_multipeermap_iterator_destroy (iter);
+ return friend;
+}
+
+
+/**
+ * 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_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);
+
+ /* 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. 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
+ */
+static void
+send_find_finger_trail_message (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct FriendInfo *target_friend;
+ struct GNUNET_TIME_Relative next_send_time;
+ struct GNUNET_HashCode trail_id;
+ 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,
+ DHT_FIND_FINGER_TRAIL_INTERVAL.rel_value_us);
+ find_finger_trail_task =
+ 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)
+ 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,
+ target_friend->id, target_friend, 0, NULL,
+ is_predecessor, trail_id, NULL);
+}
+
+
+/**
+ * In case there are already maximum number of possible trails to reach to a
+ * finger, then check if the new trail's length is lesser than any of the
+ * existing trails.
+ * If yes then replace that old trail by new trail.
+ *
+ * Note: Here we are taking length as a parameter to choose the best possible
+ * trail, but there could be other parameters also like:
+ * 1. duration of existence of a trail - older the better.
+ * 2. if the new trail is completely disjoint than the
+ * other trails, then may be choosing it is better.
+ *
+ * @param existing_finger
+ * @param new_finger_trail
+ * @param new_finger_trail_length
+ * @param new_finger_trail_id
+ */
+static void
+select_and_replace_trail (struct FingerInfo *existing_finger,
+ const struct GNUNET_PeerIdentity *new_trail,
+ unsigned int new_trail_length,
+ struct GNUNET_HashCode new_trail_id)
+{
+ struct Trail *trail_list_iterator;
+ unsigned int largest_trail_length;
+ unsigned int largest_trail_index;
+ struct Trail_Element *trail_element;
+ unsigned int i;
+
+ largest_trail_length = new_trail_length;
+ largest_trail_index = MAXIMUM_TRAILS_PER_FINGER + 1;
+
+ GNUNET_assert (MAXIMUM_TRAILS_PER_FINGER == existing_finger->trails_count);
+
+ for (i = 0; i < existing_finger->trails_count; i++)
+ {
+ trail_list_iterator = &existing_finger->trail_list[i];
+ if (trail_list_iterator->trail_length > largest_trail_length)
+ {
+ largest_trail_length = trail_list_iterator->trail_length;
+ largest_trail_index = i;
+ }
+ }
+
+ if (largest_trail_index == (MAXIMUM_TRAILS_PER_FINGER + 1))
+ {
+ // tear down new trail: it's not better than the existing ones
+ return;
+ }
+
+ /* Send trail teardown message across the replaced trail. */
+ struct Trail *replace_trail = &existing_finger->trail_list[largest_trail_index];
+
+ 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_non_null (trail_element);
+ }
+
+ /* Add new trial at that location. */
+ i = 0;
+ while (i < new_trail_length)
+ {
+ struct Trail_Element *element = GNUNET_new (struct Trail_Element);
+ element->peer = new_trail[i];
+
+ GNUNET_CONTAINER_DLL_insert_tail (replace_trail->trail_head,
+ replace_trail->trail_tail,
+ element);
+ }
+}
+
+
+/**
+ * Check if the new trail to reach to finger is unique or do we already have
+ * such a trail present for finger.
+ * @param existing_finger Finger identity
+ * @param new_trail New trail to reach @a existing_finger
+ * @param trail_length Total number of peers in new_trail.
+ * @return #GNUNET_YES if the new trail is unique
+ * #GNUNET_NO if same trail is already present.
+ */
+static int
+is_new_trail_unique (struct FingerInfo *existing_finger,
+ const struct GNUNET_PeerIdentity *new_trail,
+ unsigned int trail_length)
+{
+ struct Trail *trail_list_iterator;
+ struct Trail_Element *trail_element;
+ int i;
+ int j;
+ int trail_unique = GNUNET_NO;
+
+ for (i = 0; i < existing_finger->trails_count; i++)
+ {
+ trail_list_iterator = &existing_finger->trail_list[i];
+ if (trail_list_iterator->trail_length != trail_length)
+ continue;
+ trail_element = trail_list_iterator->trail_head;
+ for (j = 0; j < trail_list_iterator->trail_length; j++)
+ {
+ if (0 != GNUNET_CRYPTO_cmp_peer_identity (&new_trail[j],
+ &trail_element->peer))
+ {
+ trail_unique = GNUNET_YES;
+ break;
+ }
+ }
+ }
+ return trail_unique;
+}
+
+
+/**
+ * Add a new trail to existing finger.
+ * @param existing_finger
+ * @param new_finger_trail
+ * @param new_finger_trail_length
+ * @param new_finger_trail_id
+ */
+static void
+add_new_trail (struct FingerInfo *existing_finger,
+ const struct GNUNET_PeerIdentity *new_trail,
+ unsigned int new_trail_length,
+ struct GNUNET_HashCode new_trail_id)
+{
+ struct Trail *trail_list_iterator;
+ struct FriendInfo *first_friend;
+ int i;
+
+ if (GNUNET_NO == is_new_trail_unique (existing_finger, new_trail,
+ new_trail_length))
+ {
+ return;
+ }
+
+ // FIXME checking trail_head is NOT a valid way to verify an open slot
+ for (i = 0; existing_finger->trail_list[i].trail_head != NULL; i++)
+ GNUNET_assert (i < MAXIMUM_TRAILS_PER_FINGER);
+
+ trail_list_iterator = &existing_finger->trail_list[i];
+
+ if (new_trail_length > 0)
+ first_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &new_trail[0]);
+ else
+ first_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &(existing_finger->finger_identity));
+ first_friend->trails_count++;
+ /* FIXME; we removed this field but read fixme. */
+ //trail_list_iterator->first_friend_trail_count = first_friend->trails_count;
+ trail_list_iterator->trail_length = new_trail_length;
+
+ for (i = 0; i < new_trail_length; i++)
+ {
+ struct Trail_Element *element;
+ element = GNUNET_new (struct Trail_Element);
+
+ element->peer = new_trail[i];
+ GNUNET_CONTAINER_DLL_insert_tail (trail_list_iterator->trail_head,
+ trail_list_iterator->trail_tail,
+ element);
+ }
+ existing_finger->trails_count++;
+}
+
+
+/**
+ * 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,
+ struct Trail *trail)
+{
+ /* 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);
+}
+
+
+/**
+ * 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 = &finger->trail_list[i];
+ if (trail->trail_length > 0)
+ {
+ /* decerement the friend trails count. */
+ send_trail_teardown (finger, trail);
+ }
+ }
+}
+
+
+/**
+ * Free a specific trail
+ * @param trail List of peers to be freed.
+ */
+static void
+free_trail (struct Trail *trail)
+{
+ struct Trail_Element *trail_element;
+
+ while (NULL != (trail_element = trail->trail_head))
+ {
+ 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;
+}
+
+
+/**
+ * Free finger and its trail.
+ * @param finger Finger to be freed.
+ */
+static void
+free_finger (struct FingerInfo *finger, unsigned int finger_table_index)
+{
+ struct Trail *trail;
+ unsigned int i;
+
+ for (i = 0; i < finger->trails_count; i++)
+ {
+ trail = &finger->trail_list[i];
+ if (GNUNET_NO == trail->is_present)
+ continue;
+
+ if (trail->trail_length > 0)
+ free_trail (trail);
+ }
+
+ finger->is_present = GNUNET_NO;
+ memset ((void *)&finger_table[finger_table_index], 0, sizeof (finger_table[finger_table_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_table_index Index in finger table.
+ */
+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 *trail;
+ int i = 0;
+
+ new_entry = GNUNET_new (struct FingerInfo);
+ new_entry->finger_identity = finger_identity;
+ 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;
+ first_trail_hop->trails_count++;
+
+ /* Copy the finger trail into trail. */
+ trail = GNUNET_new (struct Trail);
+ 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 (trail->trail_head,
+ trail->trail_tail,
+ element);
+ i++;
+ }
+
+ /* 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;
+}
+
+
+/**
+ * Scan the trail to check if there is any other friend in the trail other than
+ * first hop. If yes then shortcut the trail, send trail compression message to
+ * peers which are no longer part of trail and send back the updated trail
+ * and trail_length to calling function.
+ * @param finger_identity Finger whose trail we will scan.
+ * @param finger_trail [in, out] Trail to reach from source to finger,
+ * @param finger_trail_length Total number of peers in original finger_trail.
+ * @param finger_trail_id Unique identifier of the finger trail.
+ * @return updated trail length in case we shortcut the trail, else original
+ * trail length.
+ */
+static struct GNUNET_PeerIdentity *
+scan_and_compress_trail (struct GNUNET_PeerIdentity finger_identity,
+ const struct GNUNET_PeerIdentity *trail,
+ unsigned int trail_length,
+ struct GNUNET_HashCode trail_id,
+ int *new_trail_length)
+{
+ struct FriendInfo *target_friend;
+ 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]);
+ /* 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);
+ }
+ 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;
+ int j = 0;
+
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &trail[0]);
+ GDS_NEIGHBOURS_send_trail_compression (my_identity,
+ trail_id, trail[i],
+ target_friend);
+
+
+ /* 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)
+ {
+ memcpy (&new_trail[j], &trail[i], sizeof(struct GNUNET_PeerIdentity));
+ j++;
+ i++;
+ }
+ *new_trail_length = j+1;
+ 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, trail, trail_length * sizeof (struct GNUNET_PeerIdentity));
+ return new_trail;
+}
+
+
+/**
+ * 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)
+{
+ /*
+ * 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_HashCode trail_id;
+ int i;
+
+ /* 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++)
+ {
+ 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)
+ {
+ peer_list[j] = element->peer;
+ element = element->next;
+ j++;
+ }
+
+ GNUNET_assert (NULL != (target_friend =
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &peer_list[0])));
+ GDS_NEIGHBOURS_send_verify_successor_message (my_identity,
+ successor->finger_identity,
+ trail_id, peer_list, trail_length,
+ target_friend);
+
+ }
+}
+
+
+/**
+ * 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 finger_identity,
+ unsigned int finger_table_index)
+{
+ struct FingerInfo *successor;
+
+ if (finger_table_index != current_search_finger_index)
+ return;
+
+ 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 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);
+ }
+ return;
+ }
+
+ current_search_finger_index = current_search_finger_index - 1;
+ return;
+}
+
+
+/**
+ * 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_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 unsigned int
+get_finger_table_index (uint64_t ultimate_destination_finger_value,
+ unsigned int is_predecessor)
+{
+ uint64_t my_id64;
+ int diff;
+ unsigned int finger_table_index;
+
+ memcpy (&my_id64, &my_identity, sizeof (uint64_t));
+ my_id64 = GNUNET_ntohll (my_id64);
+
+ /* Is this a predecessor finger? */
+ if (1 == is_predecessor)
+ {
+ 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
+ {
+ 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->is_present = GNUNET_NO;
+ memset ((void *)&finger_table[finger_table_index], 0, sizeof (finger_table[finger_table_index]));
+ return;
+ }
+
+ /* 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);
+
+ 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);
+ }
+ }
+}
+
+
+/**
+ * This is a test function, to print all the entries of finger table.
+ */
+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,
+ unsigned int is_predecessor,
+ uint64_t finger_value,
+ struct GNUNET_HashCode finger_trail_id)
+{
+ struct FingerInfo *existing_finger;
+ struct GNUNET_PeerIdentity *closest_peer;
+ struct GNUNET_PeerIdentity *updated_trail;
+ struct FingerInfo *successor;
+ int updated_finger_trail_length;
+ unsigned int finger_table_index;
+
+ //test_friend_peermap_print();
+ //test_finger_table_print();
+
+ /* 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;
+ }
+
+ 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 = &finger_table[finger_table_index];
+
+ /* No entry present in finger_table for given finger map index. */
+ if (GNUNET_NO == existing_finger->is_present)
+ {
+ 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. */
+ if (0 != GNUNET_CRYPTO_cmp_peer_identity (&(existing_finger->finger_identity),
+ &finger_identity))
+ {
+ closest_peer = select_closest_peer (&existing_finger->finger_identity,
+ &finger_identity,
+ finger_value, finger_table_index);
+
+ /* If the new finger is the closest peer. */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger_identity, closest_peer))
+ {
+ 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;
+
+ /* If the existing finger is not a friend. */
+ if (NULL ==
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &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);
+ else
+ select_and_replace_trail (existing_finger, updated_trail,
+ finger_trail_length, finger_trail_id);
+ }
+ }
+ update_current_search_finger_index (finger_identity, finger_table_index);
+ return;
}
/**
- * Core handler for P2P put messages.
+ * Core handler for P2P put messages.
* @param cls closure
* @param peer sender of the request
* @param message message
* @return #GNUNET_OK to keep the connection open,
* #GNUNET_SYSERR to close it (signal serious error)
*/
-static int
+static int
handle_dht_p2p_put (void *cls, const struct GNUNET_PeerIdentity *peer,
const struct GNUNET_MessageHeader *message)
{
- struct PeerPutMessage *put;
+ struct PeerPutMessage *put;
struct GNUNET_PeerIdentity *put_path;
struct GNUNET_HashCode test_key;
enum GNUNET_DHT_RouteOption options;
- struct GNUNET_PeerIdentity current_destination;
- struct GNUNET_PeerIdentity current_source;
+ struct GNUNET_PeerIdentity best_known_dest;
+ struct GNUNET_HashCode intermediate_trail_id;
struct GNUNET_PeerIdentity *next_hop;
void *payload;
size_t msize;
return GNUNET_YES;
}
- current_destination = put->current_destination;
- current_source = put->current_source;
+ best_known_dest = put->best_known_destination;
put_path = (struct GNUNET_PeerIdentity *) &put[1];
payload = &put_path[putlen];
options = ntohl (put->options);
+ intermediate_trail_id = put->intermediate_trail_id;
+
payload_size = msize - (sizeof (struct PeerPutMessage) +
putlen * sizeof (struct GNUNET_PeerIdentity));
}
}
- struct GNUNET_PeerIdentity pp[putlen + 1];
/* extend 'put path' by sender */
- /* FIXME: Check what are we doing here? */
+ struct GNUNET_PeerIdentity pp[putlen + 1];
if (0 != (options & GNUNET_DHT_RO_RECORD_ROUTE))
{
memcpy (pp, put_path, putlen * sizeof (struct GNUNET_PeerIdentity));
putlen = 0;
memcpy (&key_value, &(put->key), sizeof (uint64_t));
- if (0 != (GNUNET_CRYPTO_cmp_peer_identity (¤t_destination, &my_identity)))
+ if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&best_known_dest, &my_identity)))
{
- GDS_ROUTING_print();
- next_hop = GDS_ROUTING_search (¤t_source, ¤t_destination, peer);
- if (next_hop == NULL)
- {
- /* refer to handle_dht_p2p_trail_setup. */
- }
+ next_hop = GDS_ROUTING_get_next_hop (intermediate_trail_id,
+ GDS_ROUTING_SRC_TO_DEST);
}
else
{
- next_hop = find_successor (key_value, ¤t_destination, ¤t_source,PUT_GET_REQUEST);
+ next_hop = find_successor (key_value, &best_known_dest,
+ &intermediate_trail_id, GDS_FINGER_TYPE_NON_PREDECESSOR);
}
+ if (NULL == next_hop)
+ {
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop ("# Next hop to forward the packet not found "
+ "trail setup request, packet dropped."),
+ 1, GNUNET_NO);
+ return GNUNET_SYSERR;
+ }
+
+ GDS_CLIENTS_process_put (options,
+ ntohl (put->block_type),
+ ntohl (put->hop_count),
+ ntohl (put->desired_replication_level),
+ putlen, pp,
+ GNUNET_TIME_absolute_ntoh (put->expiration_time),
+ &put->key,
+ payload,
+ payload_size);
+
if (0 == GNUNET_CRYPTO_cmp_peer_identity(&my_identity, next_hop)) /* I am the final destination */
{
GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (put->expiration_time),
&(put->key),putlen, pp, ntohl (put->block_type),
payload_size, payload);
- return GNUNET_YES;
+ return GNUNET_YES;
}
else
{
- GDS_CLIENTS_process_put (options,
- ntohl (put->block_type),
- ntohl (put->hop_count),
- ntohl (put->desired_replication_level),
- putlen, pp,
- GNUNET_TIME_absolute_ntoh (put->expiration_time),
- &put->key,
- payload,
- payload_size);
- GDS_NEIGHBOURS_send_put (&put->key, payload, payload_size,
+ GDS_NEIGHBOURS_send_put (&put->key,
ntohl (put->block_type),ntohl (put->options),
ntohl (put->desired_replication_level),
+ &best_known_dest, &intermediate_trail_id, next_hop,
+ ntohl (put->hop_count), putlen, pp,
GNUNET_TIME_absolute_ntoh (put->expiration_time),
- current_destination, current_source, next_hop,
- ntohl (put->hop_count), putlen, pp);
+ payload, payload_size);
return GNUNET_YES;
}
{
struct PeerGetMessage *get;
struct GNUNET_PeerIdentity *get_path;
- struct GNUNET_PeerIdentity current_destination;
- struct GNUNET_PeerIdentity current_source;
+ struct GNUNET_PeerIdentity best_known_dest;
+ struct GNUNET_HashCode intermediate_trail_id;
struct GNUNET_PeerIdentity *next_hop;
uint32_t get_length;
uint64_t key_value;
get = (struct PeerGetMessage *)message;
get_length = ntohl (get->get_path_length);
+ best_known_dest = get->best_known_destination;
+ intermediate_trail_id = get->intermediate_trail_id;
get_path = (struct GNUNET_PeerIdentity *)&get[1];
- current_destination = get->current_destination;
- current_source = get->current_source;
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));
get_length = get_length + 1;
memcpy (&key_value, &(get->key), sizeof (uint64_t));
- if (0 != (GNUNET_CRYPTO_cmp_peer_identity (¤t_destination, &my_identity)))
+ if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&best_known_dest, &my_identity)))
{
- GDS_ROUTING_print();
- next_hop = GDS_ROUTING_search (¤t_source, ¤t_destination, peer);
- if (next_hop == NULL)
- {
- /* refer to handle_dht_p2p_trail_setup. */
- }
+ next_hop = GDS_ROUTING_get_next_hop (intermediate_trail_id,
+ GDS_ROUTING_SRC_TO_DEST);
}
else
{
- next_hop = find_successor (key_value, ¤t_destination, ¤t_source,PUT_GET_REQUEST);
+ next_hop = find_successor (key_value, &best_known_dest,
+ &intermediate_trail_id, GDS_FINGER_TYPE_NON_PREDECESSOR);
}
+ if (NULL == next_hop)
+ {
+ GNUNET_STATISTICS_update (GDS_stats,
+ gettext_noop ("# Next hop to forward the packet not found "
+ "trail setup request, packet dropped."),
+ 1, GNUNET_NO);
+ return GNUNET_SYSERR;
+ }
if (0 == GNUNET_CRYPTO_cmp_peer_identity(&my_identity, next_hop))
{
/* I am the destination.*/
memcpy (&next_hop, &final_get_path[get_length-2], sizeof (struct GNUNET_PeerIdentity));
GDS_DATACACHE_handle_get (&(get->key),(get->block_type), NULL, 0, NULL, 0,
get_length, final_get_path,&next_hop, &my_identity);
-
+
return GNUNET_YES;
}
else
{
GDS_NEIGHBOURS_send_get (&(get->key), get->block_type, get->options,
- get->desired_replication_level,current_destination,
- current_source, next_hop, 0,
+ get->desired_replication_level, &best_known_dest,
+ &intermediate_trail_id, next_hop, 0,
get_length, gp);
}
return GNUNET_SYSERR;
/**
- * FIXME: In case of trail, we don't have source and destination part of the trail,
- * Check if we follow the same in case of get/put/get_result. Also, in case of
- * put should we do a routing table add.
* Core handler for get result
* @param cls closure
* @param peer sender of the request
return GNUNET_YES;
}
- get_path = (struct GNUNET_PeerIdentity *) &get_result[1];
+ if (getlen > 0)
+ get_path = (struct GNUNET_PeerIdentity *) &get_result[1];
payload = &get_path[getlen];
payload_size = msize - (sizeof (struct PeerGetResultMessage) +
getlen * sizeof (struct GNUNET_PeerIdentity));
- /* FIXME: Check if its correct or not. */
-
+
if (putlen > 0)
put_path = &get_path[1];
else
}
else
{
- struct GNUNET_PeerIdentity *next_hop;
- next_hop = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
- /* FIXME: handle the case when current_path_index = GNUNET_SYSERR;*/
current_path_index = search_my_index (get_path, getlen);
- /* FIXME: First check if you are adding yourself to the get path or not.
- if yes then don't check if current_path_index == 0, if not then check
- and next_hop == source_peer. */
- memcpy (next_hop, &get_path[current_path_index - 1], sizeof (struct GNUNET_PeerIdentity));
-
- GDS_NEIGHBOURS_send_get_result (get_result->expiration_time, &(get_result->key),
- putlen, put_path,
- get_result->type, payload_size,payload,
- get_path, getlen,
- next_hop, &(get_result->source_peer));
+ if (GNUNET_SYSERR == current_path_index )
+ {
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+ }
+ GDS_NEIGHBOURS_send_get_result (&(get_result->key), get_result->type,
+ &get_path[current_path_index - 1],
+ &(get_result->querying_peer), putlen, put_path,
+ getlen, get_path, get_result->expiration_time,
+ payload, payload_size);
return GNUNET_YES;
}
return GNUNET_SYSERR;
/**
- * FIXME: URGENT: refactor it.
- * FIXME; now we can make a new ds to store 2 peers and one value as we are
- * using it at two places. Will complete the logic and then add a new ds.
- * In case finger map index is 64 do we need to call find_closest_predecessor?
- * Select the closest peer.
- * @param prev_hop
- * @param current_destination
- * @param current_source
- * @param value
- * @para finger_map_index
- * @return Peer which is closest, in case of error NULL.
+ * 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
*/
-struct GNUNET_PeerIdentity *
-select_closest_peer (const struct GNUNET_PeerIdentity *prev_hop,
- struct GNUNET_PeerIdentity *current_destination,
- struct GNUNET_PeerIdentity *current_source,
- uint64_t value,
- unsigned int finger_map_index)
+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 *peer1;
- struct GNUNET_PeerIdentity *peer2;
- struct Sorting_List peers[3];
- struct Sorting_List *closest_finger;
+ struct GNUNET_PeerIdentity *next_hop_to_local_best_known_dest;
- peer1 = GDS_ROUTING_search (current_source, current_destination, prev_hop);
- peer2 = find_successor (value, current_destination, current_source,finger_map_index);
+ /* 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;
+ }
+ }
- /* SUPU TEST CODE */
- struct GNUNET_PeerIdentity print_peer;
- memcpy (&print_peer, &peer1, sizeof (struct GNUNET_PeerIdentity));
- FPRINTF (stderr,_("\nSUPU %s, %s, %d,routing_peer = %s"), __FILE__, __func__,__LINE__,GNUNET_i2s(&print_peer));
- memcpy (&print_peer, &peer2, sizeof (struct GNUNET_PeerIdentity));
- FPRINTF (stderr,_("\nSUPU %s, %s, %d,find_successor_peer = %s"), __FILE__, __func__,__LINE__,GNUNET_i2s(&print_peer));
- /* SUPU TEST CODE ENDS*/
- if( (peer1 != NULL) && (peer2 != NULL))
- {
- /* Add peer 1 to the list. */
- memcpy (&peers[0], &peer1, sizeof (uint64_t));
- peers[0].type = FINGER;
- peers[0].data = NULL;
-
- /* Add peer 2 to the list. */
- memcpy (&peers[1], &peer1, sizeof (uint64_t));
- peers[0].type = FRIEND;
- peers[0].data = NULL;
-
- /* Add value to the list. */
- memcpy (&peers[2], &peer1, sizeof (uint64_t));
- peers[0].type = VALUE;
- peers[0].data = NULL;
-
- qsort (&peers, 3, sizeof (struct Sorting_List), &compare_peer_id);
- if (PREDECESSOR_FINGER_ID == finger_map_index)
- closest_finger = find_closest_predecessor (peers, value, 3);
+ 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
+ * @param peer peer identity this notification is about
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+static int
+handle_dht_p2p_trail_setup (void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message)
+{
+ const struct PeerTrailSetupMessage *trail_setup;
+ const struct GNUNET_PeerIdentity *trail_peer_list;
+ 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 final_dest_finger_val;
+ struct GNUNET_HashCode new_intermediate_trail_id;
+ struct GNUNET_HashCode intermediate_trail_id;
+ struct GNUNET_HashCode trail_id;
+ unsigned int is_predecessor;
+ uint32_t trail_length;
+ size_t msize;
+
+ msize = ntohs (message->size);
+ if (msize < sizeof (struct PeerTrailSetupMessage))
+ {
+ GNUNET_break_op (0);
+ return GNUNET_YES;
+ }
+
+ trail_setup = (const struct PeerTrailSetupMessage *) message;
+ trail_length = (msize - sizeof (struct PeerTrailSetupMessage))/
+ sizeof (struct GNUNET_PeerIdentity);
+ if ((msize - sizeof (struct PeerTrailSetupMessage)) %
+ sizeof (struct GNUNET_PeerIdentity) != 0)
+ {
+ GNUNET_break_op (0);
+ return GNUNET_OK;
+ }
+
+ trail_peer_list = (const struct GNUNET_PeerIdentity *)&trail_setup[1];
+ current_dest = trail_setup->best_known_destination;
+ trail_id = trail_setup->trail_id;
+ 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, final_dest_finger_val,
+ my_identity, is_predecessor,
+ trail_peer_list, trail_length,
+ trail_id, target_friend,
+ CONGESTION_TIMEOUT);
+ return GNUNET_OK;
+ }
+
+ local_best_known_dest = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
+
+ /* 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)))
+ {
+ /* 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))
+ {
+ GDS_ROUTING_add (trail_id, *peer, my_identity);
+ }
+ if (0 == trail_length)
+ memcpy (&next_peer, &source, sizeof (struct GNUNET_PeerIdentity));
+ else
+ memcpy (&next_peer, &trail_peer_list[trail_length-1], sizeof (struct GNUNET_PeerIdentity));
+
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_peer);
+ GDS_NEIGHBOURS_send_trail_setup_result (source,
+ my_identity,
+ target_friend, trail_length,
+ trail_peer_list,
+ 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_towards_local_best_known_dest);
+ GDS_NEIGHBOURS_send_trail_setup (source,
+ 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
+ * @param trail_length Total number of peers in @a trail_peer_list
+ * @param sender_peer Peer from which we got the message.
+ * @param finger_identity Finger to which trail is setup. It is not part of trail.
+ * @return #GNUNET_YES if sender_peer and peer from which we should receive the
+ * message are different.
+ * #GNUNET_NO if sender_peer and peer from which we should receive the
+ * message are different.
+ */
+static int
+is_sender_peer_correct (const struct GNUNET_PeerIdentity *trail_peer_list,
+ unsigned int trail_length,
+ const struct GNUNET_PeerIdentity *sender_peer,
+ struct GNUNET_PeerIdentity finger_identity,
+ struct GNUNET_PeerIdentity source_peer)
+{
+ 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)
+ {
+ if (0 != GNUNET_CRYPTO_cmp_peer_identity (&trail_peer_list[0],
+ sender_peer))
+ return GNUNET_NO;
+ }
else
- closest_finger = find_closest_successor (peers, value, 3);
+ {
+ /* 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;
- /* SUPU TEST CODE*/
- if (closest_finger->type == FINGER)
+ /* I am the last element in the trail. */
+ if ((trail_length - 1) == my_index)
{
- FPRINTF (stderr,_("\nSUPU %s, %s, %d"), __FILE__, __func__,__LINE__);
- return peer2;
+ /* Is finger the sender_peer? */
+ if (0 != GNUNET_CRYPTO_cmp_peer_identity (sender_peer,
+ &finger_identity))
+ return GNUNET_NO;
}
- else if (closest_finger->type == VALUE)
- {
- return NULL;
+ else
+ {
+ /* 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;
}
- else if (closest_finger->type == FRIEND);
+ }
+ return GNUNET_YES;
+}
+
+
+/**
+ * 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
+ * @param peer sender of this message.
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+static int
+handle_dht_p2p_trail_setup_result(void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message)
+{
+ const struct PeerTrailSetupResultMessage *trail_result;
+ const struct GNUNET_PeerIdentity *trail_peer_list;
+ struct GNUNET_PeerIdentity next_hop;
+ struct FriendInfo *target_friend;
+ struct GNUNET_PeerIdentity querying_peer;
+ struct GNUNET_PeerIdentity finger_identity;
+ uint32_t trail_length;
+ uint64_t ulitmate_destination_finger_value;
+ uint32_t is_predecessor;
+ struct GNUNET_HashCode trail_id;
+ int my_index;
+ size_t msize;
+
+ msize = ntohs (message->size);
+ if (msize < sizeof (struct PeerTrailSetupResultMessage))
+ {
+ GNUNET_break_op (0);
+ return GNUNET_YES;
+ }
+
+ trail_result = (const struct PeerTrailSetupResultMessage *) message;
+ trail_length = (msize - sizeof (struct PeerTrailSetupResultMessage))/
+ sizeof (struct GNUNET_PeerIdentity);
+ if ((msize - sizeof (struct PeerTrailSetupResultMessage)) %
+ sizeof (struct GNUNET_PeerIdentity) != 0)
+ {
+ GNUNET_break_op (0);
+ return GNUNET_OK;
+ }
+
+ is_predecessor = htonl (trail_result->is_predecessor);
+ querying_peer = trail_result->querying_peer;
+ finger_identity = trail_result->finger_identity;
+ trail_id = trail_result->trail_id;
+ 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 (GNUNET_NO == is_sender_peer_correct (trail_peer_list,
+ trail_length,
+ peer, finger_identity, querying_peer))
+ {
+ GNUNET_break_op (0);
+ return GNUNET_SYSERR;
+ }
+
+ /* Am I the one who initiated the query? */
+ 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))
{
- /* If we are returning peer2 then find_successor has already taken care
- of setting up current_destination and current_source. */
- return peer1;
+ 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;
}
- else if ((peer1 == NULL) && (peer2 == NULL))
+
+ /* Get my location in the trail. */
+ my_index = search_my_index(trail_peer_list, trail_length);
+ if (-1 == my_index)
{
- return NULL;
+ GNUNET_break_op(0);
+ return GNUNET_SYSERR;
}
- else if (peer1 == NULL)
+
+ if (my_index == 0)
+ next_hop = trail_result->querying_peer;
+ else
+ 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. */
+ if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&(trail_result->querying_peer),
+ &(trail_result->finger_identity))))
{
- return peer2;
+ GDS_ROUTING_add (trail_id, next_hop, *peer);
}
- else if (peer2 == NULL)
+
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
+ GDS_NEIGHBOURS_send_trail_setup_result (querying_peer, finger_identity,
+ target_friend, trail_length, trail_peer_list,
+ is_predecessor,
+ ulitmate_destination_finger_value,
+ trail_id);
+ return GNUNET_OK;
+}
+
+
+/**
+ * Invert the trail.
+ * @param trail Trail to be inverted
+ * @param trail_length Total number of peers in the trail.
+ * @return Updated trail
+ */
+static struct GNUNET_PeerIdentity *
+invert_trail (const struct GNUNET_PeerIdentity *trail,
+ unsigned int trail_length)
+{
+ int i;
+ int j;
+ struct GNUNET_PeerIdentity *inverted_trail;
+
+ inverted_trail = GNUNET_malloc (sizeof(struct GNUNET_PeerIdentity) *
+ trail_length);
+ i = 0;
+ j = trail_length - 1;
+ while (i < trail_length)
{
- return peer1;
+ inverted_trail[i] = trail[j];
+ i++;
+ j--;
+ }
+ return inverted_trail;
+}
+
+
+/**
+ * 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 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 *trail_length)
+{
+ struct GNUNET_PeerIdentity *trail_me_to_predecessor;
+ struct Trail *trail;
+ struct Trail_Element *trail_element;
+ struct FingerInfo *my_predecessor;
+ unsigned int i;
+ unsigned int shortest_trail_length = 0;
+ unsigned int trail_index = 0;
+
+ 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 = &my_predecessor->trail_list[i];
+ if (trail->trail_length > shortest_trail_length)
+ continue;
+ shortest_trail_length = trail->trail_length;
+ trail_index = i;
+ }
+
+ *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;
+ trail = &my_predecessor->trail_list[trail_index];
+ trail_element = trail->trail_head;
+ while ( i < shortest_trail_length)
+ {
+ trail_me_to_predecessor[i] = trail_element->peer;
+ i++;
+ trail_element = trail_element->next;
+ }
+
+ return trail_me_to_predecessor;
+}
+
+
+/**
+ * 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 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;
+ uint64_t predecessor_value;
+
+ current_predecessor = &finger_table[PREDECESSOR_FINGER_ID];
+
+ /* No predecessor. Add finger as your predecessor. */
+ if (GNUNET_NO == current_predecessor->is_present)
+ {
+ update_predecessor (finger, trail, trail_length);
+ return;
+ }
+
+ predecessor_value = compute_finger_identity_value (PREDECESSOR_FINGER_ID);
+ closest_peer = select_closest_peer (&finger,
+ ¤t_predecessor->finger_identity,
+ predecessor_value, PREDECESSOR_FINGER_ID);
+
+ /* Finger is the closest predecessor. Remove the existing one and add the new
+ one. */
+ if (0 == GNUNET_CRYPTO_cmp_peer_identity (closest_peer, &finger))
+ {
+ remove_existing_finger (current_predecessor, PREDECESSOR_FINGER_ID);
+ update_predecessor (finger, trail, trail_length);
+ return;
}
- return NULL;
+ return;
}
-/**
- * Core handle for PeerTrailSetupMessage.
+/*
+ * 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
* @param peer peer identity this notification is about
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
static int
-handle_dht_p2p_trail_setup (void *cls, const struct GNUNET_PeerIdentity *peer,
- const struct GNUNET_MessageHeader *message)
+handle_dht_p2p_verify_successor(void *cls,
+ const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message)
{
- const struct PeerTrailSetupMessage *trail_setup;
- struct GNUNET_PeerIdentity current_destination;
- struct GNUNET_PeerIdentity current_source;
- struct GNUNET_PeerIdentity source;
+ 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 next_peer;
- struct GNUNET_PeerIdentity *trail_peer_list;
+ struct GNUNET_PeerIdentity *trail_to_predecessor;
+ struct FingerInfo *current_predecessor;
struct FriendInfo *target_friend;
- uint64_t destination_finger_value;
- uint32_t trail_length;
- uint32_t finger_map_index;
+ unsigned int trail_to_predecessor_length;
size_t msize;
-
+ unsigned int trail_length;
+
msize = ntohs (message->size);
- if (msize < sizeof (struct PeerTrailSetupMessage))
+
+ /* 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;
}
- trail_setup = (const struct PeerTrailSetupMessage *) message;
- trail_length = ntohl (trail_setup->trail_length);
-
- if ((msize < sizeof (struct PeerTrailSetupMessage) +
- trail_length * sizeof (struct GNUNET_PeerIdentity)) ||
- (trail_length >
- GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
+ vsm = (const struct PeerVerifySuccessorMessage *) message;
+ trail_length = (msize - sizeof (struct PeerVerifySuccessorMessage))/
+ sizeof (struct GNUNET_PeerIdentity);
+ if ((msize - sizeof (struct PeerVerifySuccessorMessage)) %
+ sizeof (struct GNUNET_PeerIdentity) != 0)
{
GNUNET_break_op (0);
- return GNUNET_OK;
- }
+ return GNUNET_OK;
+ }
- if (trail_length > 0)
- trail_peer_list = (struct GNUNET_PeerIdentity *)&trail_setup[1];
- memcpy (¤t_destination, &(trail_setup->current_destination), sizeof (struct GNUNET_PeerIdentity));
- memcpy (¤t_source,&(trail_setup->current_source), sizeof (struct GNUNET_PeerIdentity));
- memcpy (&source, &(trail_setup->source_peer), sizeof (struct GNUNET_PeerIdentity));
- finger_map_index = ntohl (trail_setup->finger_map_index);
- destination_finger_value = ntohl (trail_setup->destination_finger);
-
- /* Check your routing table size, and if you can handle any more trails through you. */
- if (GNUNET_YES == GDS_ROUTING_check_threshold())
- {
- GDS_NEIGHBOURS_send_trail_rejection (&source, destination_finger_value, &my_identity,
- peer, finger_map_index, trail_peer_list, trail_length);
- return GNUNET_OK;
- }
+ trail_id = vsm->trail_id;
+ source_peer = vsm->source_peer;
+ successor = vsm->successor;
+ trail = (struct GNUNET_PeerIdentity *)&vsm[1];
- /* Check if you are current_destination or not. */
- if (0 != (GNUNET_CRYPTO_cmp_peer_identity (¤t_destination, &my_identity)))
- {
- next_hop = select_closest_peer (peer, ¤t_destination, ¤t_source,
- destination_finger_value, finger_map_index);
- }
- else
- {
- next_hop = find_successor (destination_finger_value, ¤t_destination,
- ¤t_source,finger_map_index);
- }
+ //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.
- if (NULL == next_hop)
- {
- GNUNET_STATISTICS_update (GDS_stats,
- gettext_noop ("# Trail not found in routing table during"
- "trail setup request, packet dropped."),
- 1, GNUNET_NO);
- return GNUNET_SYSERR;
- }
- else if (0 == (GNUNET_CRYPTO_cmp_peer_identity (next_hop, &my_identity)))/* This means I am the final destination */
+ /* 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)))
{
- if (trail_length == 0)
- {
- memcpy (&next_peer, &source, sizeof (struct GNUNET_PeerIdentity));
- }
- else
+ next_hop = GDS_ROUTING_get_next_hop (trail_id, GDS_ROUTING_SRC_TO_DEST);
+ if (NULL == next_hop)
{
- memcpy (&next_peer, &trail_peer_list[trail_length-1], sizeof (struct GNUNET_PeerIdentity));
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
}
-
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_peer);
- GDS_NEIGHBOURS_send_trail_setup_result (&source,
- &(my_identity),
- target_friend, trail_length,
- trail_peer_list,
- finger_map_index);
- return GNUNET_OK;
- }
- else
- {
- /* Now add yourself to the trail. */
- struct GNUNET_PeerIdentity peer_list[trail_length + 1];
- if (trail_length != 0)
- memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
- peer_list[trail_length] = my_identity;
- trail_length++;
target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
- GDS_NEIGHBOURS_send_trail_setup (&source,
- destination_finger_value,
- ¤t_destination, ¤t_source,
- target_friend, trail_length, peer_list,
- finger_map_index);
- return GNUNET_OK;
- }
-}
-
-/**
- * Core handle for p2p trail construction result messages.
- * @param closure
- * @param message message
- * @param peer peer identity this notification is about
- * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
- */
-static int
-handle_dht_p2p_trail_setup_result(void *cls, const struct GNUNET_PeerIdentity *peer,
- const struct GNUNET_MessageHeader *message)
-{
- const struct PeerTrailSetupResultMessage *trail_result;
- struct GNUNET_PeerIdentity *trail_peer_list;
- struct GNUNET_PeerIdentity destination_peer;
- struct GNUNET_PeerIdentity finger_identity;
- uint32_t trail_length;
- uint32_t finger_map_index;
- size_t msize;
-
- msize = ntohs (message->size);
- if (msize < sizeof (struct PeerTrailSetupResultMessage))
- {
- GNUNET_break_op (0);
- return GNUNET_YES;
- }
-
- trail_result = (const struct PeerTrailSetupResultMessage *) message;
- trail_length = ntohl (trail_result->trail_length);
-
- if ((msize <
- sizeof (struct PeerTrailSetupResultMessage) +
- trail_length * sizeof (struct GNUNET_PeerIdentity)) ||
- (trail_length >
- GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
- {
- GNUNET_break_op (0);
- return GNUNET_YES;
+ GDS_NEIGHBOURS_send_verify_successor_message (source_peer, successor,
+ trail_id, trail, trail_length,
+ target_friend);
+ return GNUNET_OK;
}
- finger_map_index = htonl (trail_result->finger_map_index);
- memcpy (&destination_peer, &(trail_result->destination_peer), sizeof (struct GNUNET_PeerIdentity));
- memcpy (&finger_identity, &(trail_result->finger_identity), sizeof (struct GNUNET_PeerIdentity));
-
- if (trail_length > 0)
- trail_peer_list = (struct GNUNET_PeerIdentity *) &trail_result[1];
+ /* I am the destination of this message. */
+ /* Check if there is a predecessor or not. */
+ compare_and_update_predecessor (source_peer, trail, trail_length);
- if (0 == (GNUNET_CRYPTO_cmp_peer_identity (&(trail_result->destination_peer),
- &my_identity)))
+ 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)))
{
- finger_table_add (&(trail_result->finger_identity), trail_peer_list, trail_length,
- finger_map_index);
- return GNUNET_YES;
+ trail_to_predecessor = NULL;
+ trail_to_predecessor_length = 0;
}
else
{
- struct GNUNET_PeerIdentity next_hop;
- struct FriendInfo *target_friend;
- int my_index;
-
- my_index = search_my_index (trail_peer_list, trail_length);
- if (my_index == GNUNET_SYSERR)
- return GNUNET_SYSERR;
-
- if (my_index == 0)
+ if (NULL == (GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ ¤t_predecessor->finger_identity)))
{
- next_hop = trail_result->destination_peer;
+ /* 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
- next_hop = trail_peer_list[my_index - 1];
-
- if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&(trail_result->destination_peer),
- &(trail_result->finger_identity))))
{
- struct GNUNET_PeerIdentity *routing_next_hop;
-
- routing_next_hop = GDS_ROUTING_search (&destination_peer,&finger_identity,
- peer);
- if ((NULL == routing_next_hop) ||
- (0 != GNUNET_CRYPTO_cmp_peer_identity(routing_next_hop, &next_hop)))
- {
- GDS_ROUTING_add (&(trail_result->destination_peer), &(trail_result->finger_identity),
- peer, &next_hop);
- }
- GDS_ROUTING_print();
+ trail_to_predecessor = NULL;
+ trail_to_predecessor_length = 0;
}
-
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
- GDS_NEIGHBOURS_send_trail_setup_result (&(trail_result->destination_peer),
- &(trail_result->finger_identity),
- target_friend, trail_length,
- trail_peer_list,
- finger_map_index);
- return GNUNET_YES;
}
- return GNUNET_SYSERR;
+
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer);
+ GDS_NEIGHBOURS_send_verify_successor_result (source_peer, my_identity,
+ current_predecessor->finger_identity,
+ trail_id, trail_to_predecessor,
+ trail_to_predecessor_length,
+ GDS_ROUTING_DEST_TO_SRC,
+ target_friend);
+ return GNUNET_OK;
}
/**
- * Get my current predecessor from the finger peer map
- * @return Current predecessor.
+ * 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 FingerInfo *
-get_predecessor()
+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_CONTAINER_MultiPeerMapIterator *finger_iter;
- struct GNUNET_PeerIdentity key_ret;
- unsigned int finger_index;
- struct FingerInfo *my_predecessor;
- int flag = 0;
-
- /* Iterate over finger peer map and extract your predecessor. */
- finger_iter = GNUNET_CONTAINER_multipeermap_iterator_create (finger_peermap);
- for (finger_index = 0; finger_index < GNUNET_CONTAINER_multipeermap_size (finger_peermap); finger_index++)
- {
- if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next
- (finger_iter,&key_ret,(const void **)&my_predecessor))
- {
- if(PREDECESSOR_FINGER_ID == my_predecessor->finger_map_index)
- {
- flag = 1;
- break;
- }
- }
- }
- GNUNET_CONTAINER_multipeermap_iterator_destroy (finger_iter);
-
- if (0 == flag)
- return NULL;
- else
- return my_predecessor;
+ 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;
}
/**
- * Core handle for p2p verify successor messages.
- * @param cls closure
- * @param message message
- * @param peer peer identity this notification is about
- * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ * 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 int
-handle_dht_p2p_verify_successor(void *cls, const struct GNUNET_PeerIdentity *peer,
- const struct GNUNET_MessageHeader *message)
+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)
{
- const struct PeerVerifySuccessorMessage *vsm;
- const struct GNUNET_PeerIdentity *trail_peer_list;
- struct GNUNET_PeerIdentity source_peer;
- struct GNUNET_PeerIdentity next_hop;
+ 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;
- size_t msize;
- uint32_t trail_length;
-
- msize = ntohs (message->size);
- if (msize < sizeof (struct PeerVerifySuccessorMessage))
- {
- GNUNET_break_op (0);
- return GNUNET_YES;
- }
- vsm = (struct PeerVerifySuccessorMessage *) message;
- trail_length = ntohl (vsm->trail_length);
+ current_successor = &finger_table[0];
+ GNUNET_assert (GNUNET_YES == current_successor->is_present);
- if ((msize < sizeof (struct PeerVerifySuccessorMessage) +
- trail_length * sizeof (struct GNUNET_PeerIdentity)) ||
- (trail_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
- {
- GNUNET_break_op (0);
- return GNUNET_YES;
- }
- if (trail_length > 0)
- trail_peer_list = (const struct GNUNET_PeerIdentity *)&vsm[1];
- memcpy (&source_peer, &(vsm->source_peer), sizeof(struct GNUNET_PeerIdentity));
+ /* 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(0 == (GNUNET_CRYPTO_cmp_peer_identity (&(vsm->successor),&my_identity)))
+ /* If probable successor is not a friend, then add an entry in your own
+ routing table. */
+ if (trail_to_new_successor_length > 0)
{
- struct FingerInfo *my_predecessor;
- if (trail_length == 0)
- {
- memcpy (&next_hop, &source_peer, sizeof (struct GNUNET_PeerIdentity));
- }
- else
- {
- memcpy (&next_hop, &trail_peer_list[trail_length-1], sizeof (struct GNUNET_PeerIdentity));
- }
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
-
- my_predecessor = get_predecessor();
- if (NULL == my_predecessor)
- {
- /* FIXME: should we just return. */
- return GNUNET_OK;
- }
-
- if (0 == (GNUNET_CRYPTO_cmp_peer_identity (&source_peer,
- &(my_predecessor->finger_identity))))
- {
- /* Source peer and my predecessor, both are same. */
- GDS_NEIGHBOURS_send_verify_successor_result (&source_peer,
- &(my_identity),
- &(my_predecessor->finger_identity),
- target_friend,
- trail_peer_list,
- trail_length);
- }
- else
- {
- struct GNUNET_PeerIdentity *new_successor_trail;
- struct TrailPeerList *iterator;
- int new_trail_length;
- int i;
-
- new_trail_length = trail_length + my_predecessor->first_trail_length + 1;
- new_successor_trail = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity) * new_trail_length);
- if (trail_length > 0)
- memcpy (new_successor_trail, trail_peer_list, (trail_length) * sizeof (struct GNUNET_PeerIdentity));
-
- memcpy (&new_successor_trail[trail_length], &my_identity, sizeof (struct GNUNET_PeerIdentity));
-
- if (my_predecessor->first_trail_length)
- {
- iterator = GNUNET_malloc (sizeof (struct TrailPeerList));
- iterator = my_predecessor->first_trail_head;
- i = trail_length + 1;
- while (i < new_trail_length)
- {
- memcpy (&new_successor_trail[i], &(iterator->peer), sizeof (struct GNUNET_PeerIdentity));
- iterator = iterator->next;
- i++;
- }
- }
- GDS_NEIGHBOURS_send_verify_successor_result (&source_peer,
- &(my_identity),
- &(my_predecessor->finger_identity),
- target_friend,
- new_successor_trail,
- new_trail_length);
- }
-
+ 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
{
- int my_index;
-
- if (trail_length == 0)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
-
- my_index = search_my_index (trail_peer_list, trail_length);
- if (my_index == GNUNET_SYSERR)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- if (my_index == (trail_length - 1))
- {
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &(vsm->successor));
- }
- else
- {
- memcpy (&next_hop, &trail_peer_list[my_index + 1], sizeof (struct GNUNET_PeerIdentity));
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
- }
-
- GDS_NEIGHBOURS_send_verify_successor (&(vsm->source_peer), &(vsm->successor),target_friend,
- trail_peer_list, trail_length);
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
+ &probable_successor);
}
- return GNUNET_SYSERR;
+
+ 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)
{
const struct PeerVerifySuccessorResultMessage *vsrm;
- struct GNUNET_PeerIdentity *trail_peer_list;
- struct GNUNET_PeerIdentity next_hop;
+ enum GDS_ROUTING_trail_direction trail_direction;
+ struct GNUNET_PeerIdentity querying_peer;
+ 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;
- uint32_t trail_length;
-
+
msize = ntohs (message->size);
+ /* 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 = (const struct PeerVerifySuccessorResultMessage *) message;
- trail_length = ntohl (vsrm->trail_length);
+ trail_length = (msize - sizeof (struct PeerVerifySuccessorResultMessage))/
+ sizeof (struct GNUNET_PeerIdentity);
- if ((msize <
- sizeof (struct PeerVerifySuccessorResultMessage) +
- trail_length * sizeof (struct GNUNET_PeerIdentity)) ||
- (trail_length >
- GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
+ if ((msize - sizeof (struct PeerVerifySuccessorResultMessage)) %
+ sizeof (struct GNUNET_PeerIdentity) != 0)
{
GNUNET_break_op (0);
- return GNUNET_YES;
- }
+ return GNUNET_OK;
+ }
- if (trail_length > 0)
- trail_peer_list = (struct GNUNET_PeerIdentity *) &vsrm[1];
+ trail = (const struct GNUNET_PeerIdentity *) &vsrm[1];
+ querying_peer = vsrm->querying_peer;
+ trail_direction = ntohl (vsrm->trail_direction);
+ trail_id = vsrm->trail_id;
+ probable_successor = vsrm->probable_successor;
- if(0 == (GNUNET_CRYPTO_cmp_peer_identity (&(vsrm->destination_peer), &(my_identity))))
- {
- if(0 != (GNUNET_CRYPTO_cmp_peer_identity (&(vsrm->my_predecessor), &(my_identity))))
- {
- if (GNUNET_YES == finger_table_add (&(vsrm->my_predecessor), trail_peer_list, trail_length, 0))
- {
- memcpy (&next_hop, &trail_peer_list[0], sizeof (struct GNUNET_PeerIdentity));
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
- /* FIXME: first call scan_and_compress_trail and then call the notify new
- successor with new trail. */
- GDS_NEIGHBOURS_send_notify_new_successor (&my_identity, &(vsrm->my_predecessor),
- &(vsrm->source_successor),
- target_friend, trail_peer_list,
- trail_length);
- return GNUNET_OK;
- }
- else
- return GNUNET_OK;
- }
- }
- else
+ //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)))
{
- int my_index;
-
- my_index = search_my_index (trail_peer_list, trail_length);
- if (GNUNET_SYSERR == my_index)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
-
- if (my_index == 0)
- {
- memcpy (&next_hop, &(vsrm->destination_peer), sizeof (struct GNUNET_PeerIdentity));
- }
- else
- {
- memcpy (&next_hop, &trail_peer_list[my_index-1], sizeof (struct GNUNET_PeerIdentity));
- }
-
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
- GDS_NEIGHBOURS_send_verify_successor_result (&(vsrm->destination_peer),
- &(vsrm->source_successor),
- &(vsrm->my_predecessor),
- target_friend,
- trail_peer_list,
- trail_length);
+ compare_and_update_successor (probable_successor, trail, trail_length);
return GNUNET_OK;
}
- return GNUNET_SYSERR;
+
+ /*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->current_successor,
+ probable_successor, trail_id,
+ trail,
+ trail_length,
+ trail_direction, target_friend);
+ return GNUNET_OK;
}
-/**
+/*
+ * 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)
{
const struct PeerNotifyNewSuccessorMessage *nsm;
- struct GNUNET_PeerIdentity *trail_peer_list;
- struct GNUNET_PeerIdentity source_peer;
- struct GNUNET_PeerIdentity old_successor;
+ struct GNUNET_PeerIdentity *trail;
+ struct GNUNET_PeerIdentity source;
struct GNUNET_PeerIdentity new_successor;
+ struct GNUNET_HashCode trail_id;
+ struct GNUNET_PeerIdentity next_hop;
+ struct FriendInfo *target_friend;
+ int my_index;
size_t msize;
uint32_t trail_length;
-
+
msize = ntohs (message->size);
+ /* We have the trail to reach from source to new successor. */
if (msize < sizeof (struct PeerNotifyNewSuccessorMessage))
{
GNUNET_break_op (0);
return GNUNET_YES;
}
+
nsm = (const struct PeerNotifyNewSuccessorMessage *) message;
- trail_length = ntohl (nsm->trail_length);
-
- if ((msize < sizeof (struct PeerNotifyNewSuccessorMessage) +
- trail_length * sizeof (struct GNUNET_PeerIdentity)) ||
- (trail_length >
- GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
+ trail_length = (msize - sizeof (struct PeerNotifyNewSuccessorMessage))/
+ sizeof (struct GNUNET_PeerIdentity);
+ if ((msize - sizeof (struct PeerTrailRejectionMessage)) %
+ sizeof (struct GNUNET_PeerIdentity) != 0)
{
GNUNET_break_op (0);
- return GNUNET_YES;
+ return GNUNET_OK;
}
- if( trail_length > 0)
- trail_peer_list = (struct GNUNET_PeerIdentity *) &nsm[1];
- memcpy (&source_peer, &(nsm->source_peer), sizeof (struct GNUNET_PeerIdentity));
- memcpy (&old_successor, &(nsm->old_successor), sizeof (struct GNUNET_PeerIdentity));
- memcpy (&new_successor, &(nsm->destination_peer), sizeof (struct GNUNET_PeerIdentity));
+ trail = (struct GNUNET_PeerIdentity *) &nsm[1];
+ source = nsm->source_peer;
+ new_successor = nsm->new_successor;
+ trail_id = nsm->trail_id;
- if(0 == (GNUNET_CRYPTO_cmp_peer_identity (&new_successor, &my_identity)))
+ //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))
{
- /* I am the new successor. */
- struct GNUNET_PeerIdentity *new_predecessor;
- new_predecessor = GNUNET_new (struct GNUNET_PeerIdentity);
- memcpy (new_predecessor, &(nsm->source_peer), sizeof (struct GNUNET_PeerIdentity));
- if (GNUNET_YES == finger_table_add (new_predecessor, trail_peer_list, trail_length, PREDECESSOR_FINGER_ID))
+ /* Add an entry in routing table only if new predecessor is not a friend. */
+ if (NULL == GNUNET_CONTAINER_multipeermap_get(friend_peermap, &source))
{
- /* You are adding a new predecessor in your finger table. but the intermediate
- peers don't have an entry in their routing table. So, you need to check the
- return value of finger_table_Add and if its successful then you should send
- routing_add_message. */
+ GDS_ROUTING_add (trail_id, *peer, my_identity);
}
+ compare_and_update_predecessor (source, trail, trail_length);
return GNUNET_OK;
}
- else
- {
- struct FriendInfo *target_friend;
- struct GNUNET_PeerIdentity next_hop;
- int my_index;
-
- if (trail_length == 0)
- return GNUNET_SYSERR;
-
- my_index = search_my_index (trail_peer_list, trail_length);
- if (GNUNET_SYSERR == my_index)
- {
- /* FIXME: happend once */
- GNUNET_break(0);
- return GNUNET_SYSERR;
- }
-
- if (my_index == (trail_length - 1))
- {
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &(nsm->destination_peer));
- }
- else
- {
- memcpy (&next_hop, &trail_peer_list[my_index+1], sizeof (struct GNUNET_PeerIdentity));
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
- }
-
- GDS_ROUTING_remove_trail (&source_peer, &old_successor, peer);
- GDS_ROUTING_add (&(nsm->source_peer), &(nsm->destination_peer), &next_hop, peer);
- GDS_NEIGHBOURS_send_notify_new_successor (&(nsm->source_peer),
- &(nsm->destination_peer),
- &(nsm->old_successor),
- target_friend, trail_peer_list,
- 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)
+ {
+ GNUNET_break_op (0);
+ return GNUNET_SYSERR;
}
- return GNUNET_SYSERR;
+ if (trail_length == 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: pass congestion time in struct PeerTrailRejectionMessage,
- * we are calling exact same thing here as in handle_dht_p2p_trail_seutp.set
- * that value here.
- * if we make it a function then we can it here.
- * Core handler for P2P trail rejection message
+ * 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
* @param peer peer identity this notification is about
* @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)
+static int
+handle_dht_p2p_trail_setup_rejection (void *cls,
+ const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message)
{
const struct PeerTrailRejectionMessage *trail_rejection;
- struct GNUNET_PeerIdentity *trail_peer_list;
+ unsigned int trail_length;
+ const struct GNUNET_PeerIdentity *trail_peer_list;
struct FriendInfo *target_friend;
- struct GNUNET_PeerIdentity next_hop;
- struct GNUNET_PeerIdentity *next_peer;
+ struct GNUNET_TIME_Relative congestion_timeout;
+ struct GNUNET_HashCode trail_id;
+ struct GNUNET_PeerIdentity next_destination;
+ struct GNUNET_HashCode new_intermediate_trail_id;
+ struct GNUNET_PeerIdentity next_peer;
struct GNUNET_PeerIdentity source;
- struct GNUNET_PeerIdentity current_destination;
- struct GNUNET_PeerIdentity current_source;
- uint32_t trail_length;
- uint32_t finger_map_index;
- uint64_t destination_finger_value;
+ struct GNUNET_PeerIdentity *next_hop;
+ uint64_t ultimate_destination_finger_value;
+ unsigned int is_predecessor;
size_t msize;
-
+
msize = ntohs (message->size);
+ /* 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_length = ntohl (trail_rejection->trail_length);
-
- if ((msize < sizeof (struct PeerTrailRejectionMessage) +
- trail_length * sizeof (struct GNUNET_PeerIdentity)) ||
- (trail_length >
- GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
+
+ trail_rejection = (const struct PeerTrailRejectionMessage *) message;
+ trail_length = (msize - sizeof (struct PeerTrailRejectionMessage))/
+ sizeof (struct GNUNET_PeerIdentity);
+ if ((msize - sizeof (struct PeerTrailRejectionMessage)) %
+ sizeof (struct GNUNET_PeerIdentity) != 0)
{
GNUNET_break_op (0);
- return GNUNET_YES;
- }
-
- if (trail_length > 0)
- trail_peer_list = (struct GNUNET_PeerIdentity *)&trail_rejection[1];
- finger_map_index = ntohl (trail_rejection->finger_map_index);
- memcpy (&destination_finger_value, &(trail_rejection->finger_identity_value), sizeof (uint64_t));
- memcpy (&source, &(trail_rejection->source_peer), sizeof (struct GNUNET_PeerIdentity));
-
+ return GNUNET_OK;
+ }
+
+ 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 =
+ 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);
- //FIXME: target_friend->congestion_time ==?
-
- if(0 == (GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &(trail_rejection->source_peer))))
- {
+ 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(GNUNET_YES == GDS_ROUTING_check_threshold())
+
+ /* 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;
new_trail_length = 0;
- memcpy (&next_hop, &(trail_rejection->source_peer), sizeof (struct GNUNET_PeerIdentity));
+ next_hop = &source;
}
- else
+ else
{
- memcpy (&next_hop, &trail_peer_list[trail_length - 2], sizeof (struct GNUNET_PeerIdentity));
+ 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));
memcpy (new_trail, trail_peer_list, new_trail_length * sizeof (struct GNUNET_PeerIdentity));
}
- GDS_NEIGHBOURS_send_trail_rejection (&(trail_rejection->source_peer),
- destination_finger_value,
- &my_identity, &next_hop,finger_map_index,
- new_trail,new_trail_length);
- return GNUNET_YES;
- }
-
- {
- memcpy (¤t_destination, &my_identity, sizeof (struct GNUNET_PeerIdentity));
- memcpy (¤t_source, &my_identity, sizeof (struct GNUNET_PeerIdentity));
- next_peer = find_successor (destination_finger_value,¤t_destination,
- ¤t_source, finger_map_index);
- if (NULL == next_peer)
- {
- GNUNET_STATISTICS_update (GDS_stats,
- gettext_noop ("# Trail not found in routing table during"
- "trail setup request, packet dropped."),
- 1, GNUNET_NO);
- return GNUNET_SYSERR;
+
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
+ GDS_NEIGHBOURS_send_trail_rejection (source,
+ ultimate_destination_finger_value,
+ my_identity, is_predecessor,
+ new_trail,new_trail_length,trail_id,
+ target_friend, CONGESTION_TIMEOUT);
+ GNUNET_free (new_trail);
+ return GNUNET_OK;
}
- else if (0 == (GNUNET_CRYPTO_cmp_peer_identity (next_peer, &my_identity)))/* This means I am the final destination */
- {
- if (trail_length == 0)
- {
- memcpy (&next_hop, &source, sizeof (struct GNUNET_PeerIdentity));
- }
+
+ /* Look for next_hop to pass the trail setup message */
+ next_hop = find_successor (ultimate_destination_finger_value,
+ &next_destination,
+ &new_intermediate_trail_id,
+ is_predecessor);
+
+ /* 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
- {
- memcpy (&next_hop, &trail_peer_list[trail_length-1], sizeof (struct GNUNET_PeerIdentity));
- }
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
- GDS_NEIGHBOURS_send_trail_setup_result (&source,
- &(my_identity),
+ 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,
target_friend, trail_length,
trail_peer_list,
- finger_map_index);
- return GNUNET_OK;
+ is_predecessor,
+ ultimate_destination_finger_value,
+ trail_id);
}
else
{
- /* Now add yourself to the trail. */
struct GNUNET_PeerIdentity peer_list[trail_length + 1];
- if (trail_length != 0)
- memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
+
+ memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
peer_list[trail_length] = my_identity;
- trail_length++;
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
- GDS_NEIGHBOURS_send_trail_setup (&source,
- destination_finger_value,
- ¤t_destination, ¤t_source,
- target_friend, trail_length, peer_list,
- finger_map_index);
- return GNUNET_OK;
- }
- }
-
+
+ target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
+ GDS_NEIGHBOURS_send_trail_setup (source,
+ ultimate_destination_finger_value,
+ next_destination,
+ target_friend, trail_length + 1, peer_list,
+ is_predecessor, trail_id,
+ &new_intermediate_trail_id);
+ }
+ GNUNET_free (next_hop);
+ return GNUNET_OK;
}
-/* FIXME: there is a loop between in call from notify new successor to this function
- * check why and fix it.
- * 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
* @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)
+static int
+handle_dht_p2p_trail_compression (void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message)
{
- struct PeerTrailTearDownMessage *trail_teardown;
- struct GNUNET_PeerIdentity *discarded_trail;
- struct GNUNET_PeerIdentity next_hop;
+ const struct PeerTrailCompressionMessage *trail_compression;
+ struct GNUNET_PeerIdentity *next_hop;
struct FriendInfo *target_friend;
- uint32_t discarded_trail_length;
+ struct GNUNET_HashCode trail_id;
size_t msize;
- int my_index;
-
+
msize = ntohs (message->size);
- if (msize < sizeof (struct PeerTrailTearDownMessage))
+ /* Here we pass only the trail id. */
+ if (msize != sizeof (struct PeerTrailCompressionMessage))
{
GNUNET_break_op (0);
return GNUNET_OK;
}
- trail_teardown = (struct PeerTrailTearDownMessage *) message;
- discarded_trail_length = ntohl (trail_teardown->trail_length);
+ 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.
- if ((msize < sizeof (struct PeerTrailTearDownMessage) +
- discarded_trail_length * sizeof (struct GNUNET_PeerIdentity)) ||
- (discarded_trail_length >
- GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
+ /* 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)))
{
- GNUNET_break_op (0);
+ /* Update your prev hop to source of this message. */
+ GDS_ROUTING_update_trail_prev_hop (trail_id,
+ trail_compression->source_peer);
return GNUNET_OK;
}
- if (discarded_trail_length > 0)
- discarded_trail = (struct GNUNET_PeerIdentity *) &trail_teardown[1];
+ /* 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);
+ return GNUNET_OK;
+ }
- /* SUPU TEST CODE */
- struct GNUNET_PeerIdentity print_peer;
- int k = 0;
- while ( k < discarded_trail_length)
+ 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_id,
+ trail_compression->new_first_friend,
+ target_friend);
+ return GNUNET_OK;
+}
+
+
+/**
+ * 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 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)
+{
+ 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))
{
- memcpy (&print_peer, &discarded_trail[k], sizeof (struct GNUNET_PeerIdentity));
- FPRINTF (stderr,_("\nSUPU %s, %s, %d,discarded_trail[%d]=%s"),
- __FILE__, __func__,__LINE__,k,GNUNET_i2s(&print_peer));
- k++;
+ GNUNET_break_op (0);
+ return GNUNET_OK;
}
- /* SUPU TEST CODE ENDS*/
- if (0 == (GNUNET_CRYPTO_cmp_peer_identity (&(trail_teardown->new_first_friend),
- &my_identity)))
+
+ trail_teardown = (const struct PeerTrailTearDownMessage *) message;
+ trail_direction = ntohl (trail_teardown->trail_direction);
+ 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))
{
- if(0 == (GNUNET_CRYPTO_cmp_peer_identity (&(trail_teardown->destination_peer),
- &my_identity)))
- {
- return GNUNET_OK;
- }
- else
- {
- /* FIXME:
- * I am the new first hop in the trail to reach from source to destination.
- Update the trail in routing table with prev_hop == source peer. */
- return GDS_ROUTING_trail_update (&(trail_teardown->source_peer),
- &(trail_teardown->destination_peer), peer);
- }
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
}
- else
+ GNUNET_free_non_null (prev_hop);
+
+ next_hop = GDS_ROUTING_get_next_hop (trail_id, trail_direction);
+ if (NULL == next_hop)
{
- /* This should always be the case. */
- if (discarded_trail_length > 0)
- {
- my_index = search_my_index (discarded_trail, discarded_trail_length);
- if(GNUNET_SYSERR == my_index)
- return GNUNET_SYSERR;
- }
- else
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- GDS_ROUTING_print();
- if (GNUNET_NO == GDS_ROUTING_remove_trail (&(trail_teardown->source_peer),
- &(trail_teardown->destination_peer),peer))
- {
- /* Here we get GNUNET_NO, only if there is no matching entry found in routing
- table. */
- GNUNET_break (0);
- return GNUNET_YES;
- }
-
- /* In case we got this message when we removed an entry from finger table,
- then we need to send the message to destination. */
- if (my_index != (discarded_trail_length - 1))
- memcpy (&next_hop, &discarded_trail[my_index + 1], sizeof (struct GNUNET_PeerIdentity));
- else
- memcpy (&next_hop, &(trail_teardown->destination_peer), sizeof (struct GNUNET_PeerIdentity));
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
-
- GDS_NEIGHBOURS_send_trail_teardown (&(trail_teardown->source_peer),
- &(trail_teardown->destination_peer),
- discarded_trail, discarded_trail_length,
- target_friend, &(trail_teardown->new_first_friend));
- return GNUNET_YES;
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
}
- 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;
}
+
/**
- * Core handle for p2p routing table add messages.
+ * 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
* @return #GNUNET_OK on success, #GNUNET_SYSERR on error
*/
-static int
+static int
handle_dht_p2p_add_trail (void *cls, const struct GNUNET_PeerIdentity *peer,
- const struct GNUNET_MessageHeader *message)
+ const struct GNUNET_MessageHeader *message)
{
- /* This function is called in case when we update our predecessor as a new peer
- claims to be our successor. In that case as we did not do a trail setup,
- intermediate nodes don't know about this trail. our predecessor has added
- that trail but not we. So, we need to add it. Its only in case of predecessor
- and succcessor that we have a symmetric relation. */
- 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;
struct GNUNET_PeerIdentity next_hop;
- struct FriendInfo *target_friend;
+ unsigned int trail_length;
+ unsigned int my_index;
size_t msize;
- uint32_t trail_length;
- int my_index;
-
+
msize = ntohs (message->size);
+ /* 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;
- trail_length = ntohl (add_trail->trail_length);
-
- if ((msize < sizeof (struct PeerAddTrailMessage) +
- trail_length * sizeof (struct GNUNET_PeerIdentity)) ||
- (trail_length >
- GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
+
+ add_trail = (const struct PeerAddTrailMessage *) message;
+ trail_length = (msize - sizeof (struct PeerAddTrailMessage))/
+ sizeof (struct GNUNET_PeerIdentity);
+ if ((msize - sizeof (struct PeerAddTrailMessage)) %
+ sizeof (struct GNUNET_PeerIdentity) != 0)
{
GNUNET_break_op (0);
- return GNUNET_OK;
- }
-
- if (trail_length > 0)
- trail = (struct GNUNET_PeerIdentity *)&add_trail[1];
-
- my_index = search_my_index (trail, trail_length);
- if (GNUNET_SYSERR == my_index)
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- if (my_index == 0)
- memcpy(&next_hop, &(add_trail->source_peer), sizeof (struct GNUNET_PeerIdentity));
- else
- memcpy (&next_hop, &trail[my_index - 1], sizeof (struct GNUNET_PeerIdentity));
+ return GNUNET_OK;
+ }
+
+ 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;
+
+ //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.
- if (GNUNET_YES == GDS_ROUTING_add (&(add_trail->source_peer), &(add_trail->destination_peer),
- peer,&next_hop))
+ /* I am not the destination of the trail. */
+ if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &destination_peer))
{
- if (my_index != 0)
+ struct FriendInfo *target_friend;
+
+ /* Get my location in the trail. */
+ my_index = search_my_index (trail, trail_length);
+ if (GNUNET_SYSERR == my_index)
{
- target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
- GDS_NEIGHBOURS_send_add_trail_message (&(add_trail->source_peer),
- &(add_trail->destination_peer),
- trail, trail_length,target_friend);
+ GNUNET_break_op (0);
+ return GNUNET_SYSERR;
}
+
+ if (0 == 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;
}
- else
- {
- /* FIXME: there is not space in routing table to add the trail. What should
- be done. */
- return GNUNET_SYSERR;
- }
+
+ /* 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: Adapt the code for List of trails.
- * Iterate over finger_peermap, and remove entries with peer as the first element
- * of their trail.
- * @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,
- const struct GNUNET_PeerIdentity *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;
+ unsigned int matching_trails_count;
+ int i;
- if (remove_finger->first_trail_length > 0)
+ /* 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;
+
+ /* Iterate over all the trails of finger. */
+ for (i = 0; i < remove_finger->trails_count; i++)
{
- if (0 == GNUNET_CRYPTO_cmp_peer_identity (&remove_finger->first_trail_head->peer, disconnected_peer))
+ 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))
{
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_remove (finger_peermap,
- key,
- remove_finger));
- free_finger (remove_finger);
+ matching_trails_count++;
+ send_trail_teardown (remove_finger, trail);
+ if (trail->trail_length > 0)
+ free_trail (trail);
}
- }
- else if (0 == GNUNET_CRYPTO_cmp_peer_identity (&(remove_finger->finger_identity),
- disconnected_peer))
- {
- GNUNET_assert (GNUNET_YES ==
- GNUNET_CONTAINER_multipeermap_remove (finger_peermap,
- key,
- remove_finger));
- free_finger (remove_finger);
- }
+ }
+ return matching_trails_count;
+}
+
+
+/**
+ * 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;
- return GNUNET_YES;
+ /* 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)
+ {
+ remove_finger->is_present = GNUNET_NO;
+ memset ((void *)&finger_table[i], 0, sizeof (finger_table[i]));
+ }
+ }
}
const struct GNUNET_PeerIdentity *peer)
{
struct FriendInfo *remove_friend;
-
- /* Check for self message. */
+
+ /* If disconnected to own identity, then return. */
if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
return;
+
+ GNUNET_assert (NULL != (remove_friend =
+ GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer)));
- /* Search for peer to remove in your friend_peermap. */
- 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);
- if (NULL == remove_friend)
- {
- GNUNET_break (0);
- return;
- }
-
- /* Remove fingers for which this peer is the first element in the trail or if
- * the friend is a finger. */
- GNUNET_CONTAINER_multipeermap_iterate (finger_peermap,
- &remove_matching_finger, (void *)peer);
- GDS_ROUTING_remove_entry (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 the peer from friend_peermap. */
+ /* Remove peer from friend_peermap. */
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_remove (friend_peermap,
peer,
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);
+
}
/* Check for connect to self message */
if (0 == memcmp (&my_identity, peer_identity, sizeof (struct GNUNET_PeerIdentity)))
return;
-
+
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;
}
-
+
GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# peers connected"), 1,
GNUNET_NO);
friend = GNUNET_new (struct FriendInfo);
friend->id = *peer_identity;
- friend->trails_count = 0;
-
+
GNUNET_assert (GNUNET_OK ==
GNUNET_CONTAINER_multipeermap_put (friend_peermap,
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]));
+
+ }
}
static struct GNUNET_CORE_MessageHandler core_handlers[] = {
{&handle_dht_p2p_put, GNUNET_MESSAGE_TYPE_DHT_P2P_PUT, 0},
{&handle_dht_p2p_get, GNUNET_MESSAGE_TYPE_DHT_P2P_GET, 0},
- {&handle_dht_p2p_get_result, GNUNET_MESSAGE_TYPE_DHT_P2P_GET_RESULT, 0},
+ {&handle_dht_p2p_get_result, GNUNET_MESSAGE_TYPE_DHT_P2P_GET_RESULT, 0},
{&handle_dht_p2p_trail_setup, GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP, 0},
{&handle_dht_p2p_trail_setup_result, GNUNET_MESSAGE_TYPE_DHT_P2P_TRAIL_SETUP_RESULT, 0},
{&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_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}
};
-
+
core_api =
GNUNET_CORE_connect (GDS_cfg, NULL, &core_init, &handle_core_connect,
&handle_core_disconnect, NULL, GNUNET_NO, NULL,
GNUNET_NO, core_handlers);
if (NULL == core_api)
return GNUNET_SYSERR;
-
+
friend_peermap = GNUNET_CONTAINER_multipeermap_create (256, GNUNET_NO);
- finger_peermap = GNUNET_CONTAINER_multipeermap_create (MAX_FINGERS * 4/3, GNUNET_NO);
+ finger_table_init ();
return GNUNET_OK;
}
{
if (NULL == core_api)
return;
-
+
GNUNET_CORE_disconnect (core_api);
core_api = NULL;
-
+
GNUNET_assert (0 == GNUNET_CONTAINER_multipeermap_size (friend_peermap));
GNUNET_CONTAINER_multipeermap_destroy (friend_peermap);
friend_peermap = NULL;
-
- GNUNET_assert (0 == GNUNET_CONTAINER_multipeermap_size (finger_peermap));
- GNUNET_CONTAINER_multipeermap_destroy (finger_peermap);
- finger_peermap = NULL;
if (GNUNET_SCHEDULER_NO_TASK != find_finger_trail_task)
{
*
* @return my identity
*/
-struct GNUNET_PeerIdentity
+struct GNUNET_PeerIdentity
GDS_NEIGHBOURS_get_my_id (void)
{
return my_identity;
}
-
-
-/* end of gnunet-service-xdht_neighbours.c */
\ No newline at end of file
projects / oweals / gnunet.git / blobdiff