/*
This file is part of GNUnet.
Copyright (C) 2013, 2016 GNUnet e.V.
GNUnet is free software: you can redistribute it and/or modify it
under the terms of the GNU Affero General Public License as published
by the Free Software Foundation, either version 3 of the License,
or (at your option) any later version.
GNUnet is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see .
*/
/**
* @file dv/gnunet-service-dv.c
* @brief the distance vector service, primarily handles gossip of nearby
* peers and sending/receiving DV messages from core and decapsulating
* them
*
* @author Christian Grothoff
* @author Nathan Evans
*/
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_protocols.h"
#include "gnunet_core_service.h"
#include "gnunet_hello_lib.h"
#include "gnunet_peerinfo_service.h"
#include "gnunet_statistics_service.h"
#include "gnunet_set_service.h"
#include "gnunet_ats_service.h"
#include "dv.h"
#include
/**
* How often do we establish the consensu?
*/
#define GNUNET_DV_CONSENSUS_FREQUENCY GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 5)
/**
* Maximum number of messages we queue per peer.
*/
#define MAX_QUEUE_SIZE 16
/**
* Maximum number of messages we queue towards the clients/plugin.
*/
#define MAX_QUEUE_SIZE_PLUGIN 1024
/**
* The default fisheye depth, from how many hops away will
* we keep peers?
*/
#define DEFAULT_FISHEYE_DEPTH 3
/**
* How many hops is a direct neighbor away?
*/
#define DIRECT_NEIGHBOR_COST 1
GNUNET_NETWORK_STRUCT_BEGIN
/**
* Information about a peer DV can route to. These entries are what
* we use as the binary format to establish consensus to create our
* routing table and as the address format in the HELLOs.
*/
struct Target
{
/**
* Identity of the peer we can reach.
*/
struct GNUNET_PeerIdentity peer;
/**
* How many hops (1-3) is this peer away? in network byte order
*/
uint32_t distance GNUNET_PACKED;
};
/**
* Message exchanged between DV services (via core), requesting a
* message to be routed.
*/
struct RouteMessage
{
/**
* Type: #GNUNET_MESSAGE_TYPE_DV_ROUTE
*/
struct GNUNET_MessageHeader header;
/**
* Expected (remaining) distance. Must be always smaller than
* #DEFAULT_FISHEYE_DEPTH, should be zero at the target. Must
* be decremented by one at each hop. Peers must not forward
* these messages further once the counter has reached zero.
*/
uint32_t distance GNUNET_PACKED;
/**
* The (actual) target of the message (this peer, if distance is zero).
*/
struct GNUNET_PeerIdentity target;
/**
* The (actual) sender of the message.
*/
struct GNUNET_PeerIdentity sender;
};
GNUNET_NETWORK_STRUCT_END
/**
* Information about a direct neighbor (core-level, excluding
* DV-links, only DV-enabled peers).
*/
struct DirectNeighbor
{
/**
* Identity of the peer.
*/
struct GNUNET_PeerIdentity peer;
/**
* Session ID we use whenever we create a set union with
* this neighbor; constructed from the XOR of our peer
* IDs and then salted with "DV-SALT" to avoid conflicts
* with other applications.
*/
struct GNUNET_HashCode real_session_id;
/**
* Transmit handle to core service.
*/
struct GNUNET_MQ_Handle *mq;
/**
* Routing table of the neighbor, NULL if not yet established.
* Keys are peer identities, values are 'struct Target' entries.
* Note that the distances in the targets are from the point-of-view
* of the peer, not from us!
*/
struct GNUNET_CONTAINER_MultiPeerMap *neighbor_table;
/**
* Updated routing table of the neighbor, under construction,
* NULL if we are not currently building it.
* Keys are peer identities, values are 'struct Target' entries.
* Note that the distances in the targets are from the point-of-view
* of the other peer, not from us!
*/
struct GNUNET_CONTAINER_MultiPeerMap *neighbor_table_consensus;
/**
* Our current (exposed) routing table as a set.
*/
struct GNUNET_SET_Handle *my_set;
/**
* Handle for our current active set union operation.
*/
struct GNUNET_SET_OperationHandle *set_op;
/**
* Handle used if we are listening for this peer, waiting for the
* other peer to initiate construction of the set union. NULL if
* we ar the initiating peer.
*/
struct GNUNET_SET_ListenHandle *listen_handle;
/**
* ID of the task we use to (periodically) update our consensus
* with this peer. Used if we are the initiating peer.
*/
struct GNUNET_SCHEDULER_Task *initiate_task;
/**
* At what offset are we, with respect to inserting our own routes
* into the consensus?
*/
unsigned int consensus_insertion_offset;
/**
* At what distance are we, with respect to inserting our own routes
* into the consensus?
*/
unsigned int consensus_insertion_distance;
/**
* Elements in consensus
*/
unsigned int consensus_elements;
/**
* Direct one hop route
*/
struct Route *direct_route;
/**
* Flag set within 'check_target_removed' to trigger full global route refresh.
*/
int target_removed;
/**
* Our distance to this peer, 0 for unknown.
*/
uint32_t distance;
/**
* The network this peer is in
*/
enum GNUNET_NetworkType network;
/**
* Is this neighbor connected at the core level?
*/
int connected;
};
/**
* A route includes information about the next hop,
* the target, and the ultimate distance to the
* target.
*/
struct Route
{
/**
* Which peer do we need to forward the message to?
*/
struct DirectNeighbor *next_hop;
/**
* What would be the target, and how far is it away?
*/
struct Target target;
/**
* Offset of this target in the respective consensus set.
*/
unsigned int set_offset;
};
/**
* Set of targets we bring to a consensus; all targets in a set have a
* distance equal to the sets distance (which is implied by the array
* index of the set).
*/
struct ConsensusSet
{
/**
* Array of targets in the set, may include NULL entries if a
* neighbor has disconnected; the targets are allocated with the
* respective container (all_routes), not here.
*/
struct Route **targets;
/**
* Size of the @e targets array.
*/
unsigned int array_length;
};
/**
* Peermap of all of our neighbors; processing these usually requires
* first checking to see if the peer is core-connected and if the
* distance is 1, in which case they are direct neighbors.
*/
static struct GNUNET_CONTAINER_MultiPeerMap *direct_neighbors;
/**
* Hashmap with all routes that we currently support; contains
* routing information for all peers from distance 2
* up to distance #DEFAULT_FISHEYE_DEPTH.
*/
static struct GNUNET_CONTAINER_MultiPeerMap *all_routes;
/**
* Array of consensus sets we expose to the outside world. Sets
* are structured by the distance to the target.
*/
static struct ConsensusSet consensi[DEFAULT_FISHEYE_DEPTH];
/**
* Handle to the core service api.
*/
static struct GNUNET_CORE_Handle *core_api;
/**
* The identity of our peer.
*/
static struct GNUNET_PeerIdentity my_identity;
/**
* The configuration for this service.
*/
static const struct GNUNET_CONFIGURATION_Handle *cfg;
/**
* The client, the DV plugin connected to us (or an event monitor).
* Hopefully this client will never change, although if the plugin
* dies and returns for some reason it may happen.
*/
static struct GNUNET_NotificationContext *nc;
/**
* Handle for the statistics service.
*/
static struct GNUNET_STATISTICS_Handle *stats;
/**
* Handle to ATS service.
*/
static struct GNUNET_ATS_PerformanceHandle *ats;
/**
* Task scheduled to refresh routes based on direct neighbours.
*/
static struct GNUNET_SCHEDULER_Task *rr_task;
/**
* #GNUNET_YES if we are shutting down.
*/
static int in_shutdown;
/**
* Start creating a new DV set union by initiating the connection.
*
* @param cls the 'struct DirectNeighbor' of the peer we're building
* a routing consensus with
*/
static void
initiate_set_union (void *cls);
/**
* Start creating a new DV set union construction, our neighbour has
* asked for it (callback for listening peer).
*
* @param cls the 'struct DirectNeighbor' of the peer we're building
* a routing consensus with
* @param other_peer the other peer
* @param context_msg message with application specific information from
* the other peer
* @param request request from the other peer, use GNUNET_SET_accept
* to accept it, otherwise the request will be refused
* Note that we don't use a return value here, as it is also
* necessary to specify the set we want to do the operation with,
* whith sometimes can be derived from the context message.
* Also necessary to specify the timeout.
*/
static void
listen_set_union (void *cls,
const struct GNUNET_PeerIdentity *other_peer,
const struct GNUNET_MessageHeader *context_msg,
struct GNUNET_SET_Request *request);
/**
* Forward a message from another peer to the plugin.
*
* @param message the message to send to the plugin
* @param origin the original sender of the message
* @param distance distance to the original sender of the message
*/
static void
send_data_to_plugin (const struct GNUNET_MessageHeader *message,
const struct GNUNET_PeerIdentity *origin,
uint32_t distance)
{
struct GNUNET_DV_ReceivedMessage *received_msg;
size_t size;
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Delivering message from peer `%s' at distance %u\n",
GNUNET_i2s (origin),
(unsigned int) distance);
size = sizeof (struct GNUNET_DV_ReceivedMessage) +
ntohs (message->size);
if (size >= GNUNET_MAX_MESSAGE_SIZE)
{
GNUNET_break (0); /* too big */
return;
}
received_msg = GNUNET_malloc (size);
received_msg->header.size = htons (size);
received_msg->header.type = htons (GNUNET_MESSAGE_TYPE_DV_RECV);
received_msg->distance = htonl (distance);
received_msg->sender = *origin;
GNUNET_memcpy (&received_msg[1], message, ntohs (message->size));
GNUNET_notification_context_broadcast (nc,
&received_msg->header,
GNUNET_YES);
GNUNET_free (received_msg);
}
/**
* Forward a control message to the plugin.
*
* @param message the message to send to the plugin
*/
static void
send_control_to_plugin (const struct GNUNET_MessageHeader *message)
{
GNUNET_notification_context_broadcast (nc,
message,
GNUNET_NO);
}
/**
* Send a DISTANCE_CHANGED message to the plugin.
*
* @param peer peer with a changed distance
* @param distance new distance to the peer
* @param network network used by the neighbor
*/
static void
send_distance_change_to_plugin (const struct GNUNET_PeerIdentity *peer,
uint32_t distance,
enum GNUNET_NetworkType network)
{
struct GNUNET_DV_DistanceUpdateMessage du_msg;
GNUNET_break (GNUNET_NT_UNSPECIFIED != network);
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Delivering DISTANCE_CHANGED for message about peer `%s'\n",
GNUNET_i2s (peer));
du_msg.header.size = htons (sizeof (du_msg));
du_msg.header.type = htons (GNUNET_MESSAGE_TYPE_DV_DISTANCE_CHANGED);
du_msg.distance = htonl (distance);
du_msg.peer = *peer;
du_msg.network = htonl ((uint32_t) network);
send_control_to_plugin (&du_msg.header);
}
/**
* Give a CONNECT message to the plugin.
*
* @param target peer that connected
* @param distance distance to the target
* @param network the network the next hop is located in
*/
static void
send_connect_to_plugin (const struct GNUNET_PeerIdentity *target,
uint32_t distance,
enum GNUNET_NetworkType network)
{
struct GNUNET_DV_ConnectMessage cm;
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Delivering CONNECT about peer %s with distance %u\n",
GNUNET_i2s (target), distance);
cm.header.size = htons (sizeof (cm));
cm.header.type = htons (GNUNET_MESSAGE_TYPE_DV_CONNECT);
cm.distance = htonl (distance);
cm.network = htonl ((uint32_t) network);
cm.peer = *target;
send_control_to_plugin (&cm.header);
}
/**
* Give a DISCONNECT message to the plugin.
*
* @param target peer that disconnected
*/
static void
send_disconnect_to_plugin (const struct GNUNET_PeerIdentity *target)
{
struct GNUNET_DV_DisconnectMessage dm;
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Delivering DISCONNECT about peer `%s'\n",
GNUNET_i2s (target));
dm.header.size = htons (sizeof (dm));
dm.header.type = htons (GNUNET_MESSAGE_TYPE_DV_DISCONNECT);
dm.reserved = htonl (0);
dm.peer = *target;
send_control_to_plugin (&dm.header);
}
/**
* Forward the given payload to the given target.
*
* @param target where to send the message
* @param distance distance to the @a sender
* @param sender original sender of the message
* @param actual_target ultimate recipient for the message
* @param payload payload of the message
*/
static void
forward_payload (struct DirectNeighbor *target,
uint32_t distance,
const struct GNUNET_PeerIdentity *sender,
const struct GNUNET_PeerIdentity *actual_target,
const struct GNUNET_MessageHeader *payload)
{
struct GNUNET_MQ_Envelope *env;
struct RouteMessage *rm;
if ( (GNUNET_MQ_get_length (target->mq) >= MAX_QUEUE_SIZE) &&
(0 != memcmp (sender,
&my_identity,
sizeof (struct GNUNET_PeerIdentity))) )
{
/* not _our_ client and queue is full, drop */
GNUNET_STATISTICS_update (stats,
"# messages dropped",
1,
GNUNET_NO);
return;
}
if (sizeof (struct RouteMessage) + ntohs (payload->size)
>= GNUNET_MAX_MESSAGE_SIZE)
{
GNUNET_break (0);
return;
}
env = GNUNET_MQ_msg_nested_mh (rm,
GNUNET_MESSAGE_TYPE_DV_ROUTE,
payload);
rm->distance = htonl (distance);
rm->target = *actual_target;
rm->sender = *sender;
GNUNET_MQ_send (target->mq,
env);
}
/**
* Find a free slot for storing a 'route' in the 'consensi'
* set at the given distance.
*
* @param distance distance to use for the set slot
*/
static unsigned int
get_consensus_slot (uint32_t distance)
{
struct ConsensusSet *cs;
unsigned int i;
GNUNET_assert (distance < DEFAULT_FISHEYE_DEPTH);
cs = &consensi[distance];
i = 0;
while ( (i < cs->array_length) &&
(NULL != cs->targets[i]) ) i++;
if (i == cs->array_length)
{
GNUNET_array_grow (cs->targets,
cs->array_length,
cs->array_length * 2 + 2);
}
return i;
}
/**
* Allocate a slot in the consensus set for a route.
*
* @param route route to initialize
* @param distance which consensus set to use
*/
static void
allocate_route (struct Route *route,
uint32_t distance)
{
unsigned int i;
if (distance >= DEFAULT_FISHEYE_DEPTH)
{
route->target.distance = htonl (distance);
route->set_offset = UINT_MAX; /* invalid slot */
return;
}
i = get_consensus_slot (distance);
route->set_offset = i;
consensi[distance].targets[i] = route;
route->target.distance = htonl (distance);
}
/**
* Release a slot in the consensus set for a route.
*
* @param route route to release the slot from
*/
static void
release_route (struct Route *route)
{
if (UINT_MAX == route->set_offset)
return;
GNUNET_assert (ntohl (route->target.distance) < DEFAULT_FISHEYE_DEPTH);
consensi[ntohl (route->target.distance)].targets[route->set_offset] = NULL;
route->set_offset = UINT_MAX; /* indicate invalid slot */
}
/**
* Move a route from one consensus set to another.
*
* @param route route to move
* @param new_distance new distance for the route (destination set)
*/
static void
move_route (struct Route *route,
uint32_t new_distance)
{
release_route (route);
allocate_route (route, new_distance);
}
/**
* Initialize this neighbors 'my_set' and when done give
* it to the pending set operation for execution.
*
* Add a single element to the set per call:
*
* If we reached the last element of a consensus element: increase distance
*
*
* @param cls the neighbor for which we are building the set
*/
static void
build_set (void *cls)
{
struct DirectNeighbor *neighbor = cls;
struct GNUNET_SET_Element element;
struct Target *target;
struct Route *route;
target = NULL;
/* skip over NULL entries */
while ( (DEFAULT_FISHEYE_DEPTH > neighbor->consensus_insertion_distance) &&
(consensi[neighbor->consensus_insertion_distance].array_length > neighbor->consensus_insertion_offset) &&
(NULL == consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset]) )
neighbor->consensus_insertion_offset++;
while ( (DEFAULT_FISHEYE_DEPTH > neighbor->consensus_insertion_distance) &&
(consensi[neighbor->consensus_insertion_distance].array_length == neighbor->consensus_insertion_offset) )
{
/* If we reached the last element of a consensus array element: increase distance and start with next array */
neighbor->consensus_insertion_offset = 0;
neighbor->consensus_insertion_distance++;
/* skip over NULL entries */
while ( (DEFAULT_FISHEYE_DEPTH > neighbor->consensus_insertion_distance) &&
(consensi[neighbor->consensus_insertion_distance].array_length > neighbor->consensus_insertion_offset) &&
(NULL == consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset]) )
neighbor->consensus_insertion_offset++;
}
if (DEFAULT_FISHEYE_DEPTH == neighbor->consensus_insertion_distance)
{
/* we have added all elements to the set, run the operation */
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Finished building my SET for peer `%s' with %u elements, committing\n",
GNUNET_i2s (&neighbor->peer),
neighbor->consensus_elements);
GNUNET_SET_commit (neighbor->set_op,
neighbor->my_set);
GNUNET_SET_destroy (neighbor->my_set);
neighbor->my_set = NULL;
return;
}
route = consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset];
GNUNET_assert (NULL != route);
target = &route->target;
GNUNET_assert (ntohl (target->distance) < DEFAULT_FISHEYE_DEPTH);
element.size = sizeof (struct Target);
element.element_type = htons (0);
element.data = target;
/* Find next non-NULL entry */
neighbor->consensus_insertion_offset++;
if ( (0 != memcmp (&target->peer,
&my_identity,
sizeof (my_identity))) &&
(0 != memcmp (&target->peer,
&neighbor->peer,
sizeof (struct GNUNET_PeerIdentity))) )
{
/* Add target if it is not the neighbor or this peer */
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Adding peer `%s' with distance %u to SET\n",
GNUNET_i2s (&target->peer),
ntohl (target->distance) + 1);
GNUNET_SET_add_element (neighbor->my_set,
&element,
&build_set, neighbor);
neighbor->consensus_elements++;
}
else
build_set (neighbor);
}
/**
* A peer is now connected to us at distance 1. Initiate DV exchange.
*
* @param neighbor entry for the neighbor at distance 1
*/
static void
handle_direct_connect (struct DirectNeighbor *neighbor)
{
struct Route *route;
struct GNUNET_HashCode h1;
struct GNUNET_HashCode h2;
struct GNUNET_HashCode session_id;
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Direct connection to %s established, routing table exchange begins.\n",
GNUNET_i2s (&neighbor->peer));
GNUNET_STATISTICS_update (stats,
"# peers connected (1-hop)",
1, GNUNET_NO);
route = GNUNET_CONTAINER_multipeermap_get (all_routes,
&neighbor->peer);
if (NULL != route)
{
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_remove (all_routes,
&neighbor->peer,
route));
send_disconnect_to_plugin (&neighbor->peer);
release_route (route);
GNUNET_free (route);
}
neighbor->direct_route = GNUNET_new (struct Route);
neighbor->direct_route->next_hop = neighbor;
neighbor->direct_route->target.peer = neighbor->peer;
allocate_route (neighbor->direct_route, DIRECT_NEIGHBOR_COST);
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Adding direct route to %s\n",
GNUNET_i2s (&neighbor->direct_route->target.peer));
/* construct session ID seed as XOR of both peer's identities */
GNUNET_CRYPTO_hash (&my_identity,
sizeof (my_identity),
&h1);
GNUNET_CRYPTO_hash (&neighbor->peer,
sizeof (struct GNUNET_PeerIdentity),
&h2);
GNUNET_CRYPTO_hash_xor (&h1,
&h2,
&session_id);
/* make sure session ID is unique across applications by salting it with 'DV' */
GNUNET_CRYPTO_hkdf (&neighbor->real_session_id, sizeof (struct GNUNET_HashCode),
GCRY_MD_SHA512, GCRY_MD_SHA256,
"DV-SALT", 2,
&session_id, sizeof (session_id),
NULL, 0);
if (0 < memcmp (&neighbor->peer,
&my_identity,
sizeof (struct GNUNET_PeerIdentity)))
{
if (NULL != neighbor->listen_handle)
{
GNUNET_break (0);
}
else
neighbor->initiate_task = GNUNET_SCHEDULER_add_now (&initiate_set_union,
neighbor);
}
else
{
if (NULL != neighbor->listen_handle)
{
GNUNET_break (0);
}
else
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Starting SET listen operation with peer `%s'\n",
GNUNET_i2s (&neighbor->peer));
neighbor->listen_handle = GNUNET_SET_listen (cfg,
GNUNET_SET_OPERATION_UNION,
&neighbor->real_session_id,
&listen_set_union,
neighbor);
}
}
}
/**
* Method called whenever a peer connects.
*
* @param cls closure
* @param peer peer identity this notification is about
* @param mq message queue for sending data to @a peer
* @return our `struct DirectNeighbour` for this peer
*/
static void *
handle_core_connect (void *cls,
const struct GNUNET_PeerIdentity *peer,
struct GNUNET_MQ_Handle *mq)
{
struct DirectNeighbor *neighbor;
/* Check for connect to self message */
if (0 == memcmp (&my_identity,
peer,
sizeof (struct GNUNET_PeerIdentity)))
return NULL;
/* check if entry exists */
neighbor = GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
peer);
if (NULL != neighbor)
{
GNUNET_break (GNUNET_NT_UNSPECIFIED != neighbor->network);
GNUNET_break (GNUNET_YES != neighbor->connected);
neighbor->connected = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Core connected to %s (distance %u)\n",
GNUNET_i2s (peer),
(unsigned int) neighbor->distance);
if (DIRECT_NEIGHBOR_COST != neighbor->distance)
return NULL;
handle_direct_connect (neighbor);
return NULL;
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Core connected to %s (distance unknown)\n",
GNUNET_i2s (peer));
neighbor = GNUNET_new (struct DirectNeighbor);
neighbor->peer = *peer;
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_put (direct_neighbors,
&neighbor->peer,
neighbor,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
neighbor->connected = GNUNET_YES;
neighbor->distance = 0; /* unknown */
neighbor->network = GNUNET_NT_UNSPECIFIED;
return neighbor;
}
/**
* Called for each 'target' in a neighbor table to free the associated memory.
*
* @param cls NULL
* @param key key of the value
* @param value value to free
* @return #GNUNET_OK to continue to iterate
*/
static int
free_targets (void *cls,
const struct GNUNET_PeerIdentity *key,
void *value)
{
GNUNET_free (value);
return GNUNET_OK;
}
/**
* Add a new route to the given @a target via the given @a neighbor.
*
* @param target the target of the route
* @param neighbor the next hop for communicating with the @a target
*/
static void
add_new_route (struct Target *target,
struct DirectNeighbor *neighbor)
{
struct Route *route;
route = GNUNET_new (struct Route);
route->next_hop = neighbor;
route->target.peer = target->peer;
allocate_route (route, ntohl (target->distance) + 1);
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_put (all_routes,
&route->target.peer,
route,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
send_connect_to_plugin (&route->target.peer,
ntohl (route->target.distance),
neighbor->network);
}
/**
* Multipeerhmap iterator for checking if a given route is
* (now) useful to this peer.
*
* @param cls the direct neighbor for the given route
* @param key key value stored under
* @param value a 'struct Target' that may or may not be useful; not that
* the distance in 'target' does not include the first hop yet
* @return #GNUNET_YES to continue iteration, #GNUNET_NO to stop
*/
static int
check_possible_route (void *cls,
const struct GNUNET_PeerIdentity *key,
void *value)
{
struct DirectNeighbor *neighbor = cls;
struct Target *target = value;
struct Route *route;
if (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_contains (direct_neighbors,
key))
return GNUNET_YES; /* direct route, do not care about alternatives */
route = GNUNET_CONTAINER_multipeermap_get (all_routes,
key);
if (NULL != route)
{
/* we have an existing route, check how it compares with going via 'target' */
if (ntohl (route->target.distance) > ntohl (target->distance) + 1)
{
/* via 'target' is cheaper than the existing route; switch to alternative route! */
move_route (route, ntohl (target->distance) + 1);
route->next_hop = neighbor;
send_distance_change_to_plugin (&target->peer,
ntohl (target->distance) + 1,
neighbor->network);
}
return GNUNET_YES; /* got a route to this target already */
}
if (ntohl (target->distance) >= DEFAULT_FISHEYE_DEPTH)
return GNUNET_YES; /* distance is too large to be interesting */
add_new_route (target, neighbor);
return GNUNET_YES;
}
/**
* Multipeermap iterator for finding routes that were previously
* "hidden" due to a better route (called after a disconnect event).
*
* @param cls NULL
* @param key peer identity of the given direct neighbor
* @param value a `struct DirectNeighbor` to check for additional routes
* @return #GNUNET_YES to continue iteration
*/
static int
refresh_routes (void *cls,
const struct GNUNET_PeerIdentity *key,
void *value)
{
struct DirectNeighbor *neighbor = value;
if ( (GNUNET_YES != neighbor->connected) ||
(DIRECT_NEIGHBOR_COST != neighbor->distance) )
return GNUNET_YES;
if (NULL != neighbor->neighbor_table)
GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table,
&check_possible_route,
neighbor);
return GNUNET_YES;
}
/**
* Task to run #refresh_routes() on all direct neighbours.
*
* @param cls NULL
*/
static void
refresh_routes_task (void *cls)
{
rr_task = NULL;
GNUNET_CONTAINER_multipeermap_iterate (direct_neighbors,
&refresh_routes,
NULL);
}
/**
* Asynchronously run #refresh_routes() at the next opportunity
* on all direct neighbours.
*/
static void
schedule_refresh_routes ()
{
if (NULL == rr_task)
rr_task = GNUNET_SCHEDULER_add_now (&refresh_routes_task,
NULL);
}
/**
* Multipeermap iterator for freeing routes that go via a particular
* neighbor that disconnected and is thus no longer available.
*
* @param cls the direct neighbor that is now unavailable
* @param key key value stored under
* @param value a `struct Route` that may or may not go via neighbor
*
* @return #GNUNET_YES to continue iteration, #GNUNET_NO to stop
*/
static int
cull_routes (void *cls,
const struct GNUNET_PeerIdentity *key,
void *value)
{
struct DirectNeighbor *neighbor = cls;
struct Route *route = value;
if (route->next_hop != neighbor)
return GNUNET_YES; /* not affected */
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_remove (all_routes, key, value));
release_route (route);
send_disconnect_to_plugin (&route->target.peer);
GNUNET_free (route);
return GNUNET_YES;
}
/**
* Handle the case that a direct connection to a peer is
* disrupted. Remove all routes via that peer and
* stop the consensus with it.
*
* @param neighbor peer that was disconnected (or at least is no
* longer at distance 1)
*/
static void
handle_direct_disconnect (struct DirectNeighbor *neighbor)
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Culling routes via %s due to direct disconnect\n",
GNUNET_i2s (&neighbor->peer));
GNUNET_CONTAINER_multipeermap_iterate (all_routes,
&cull_routes,
neighbor);
if (NULL != neighbor->direct_route)
{
release_route (neighbor->direct_route);
GNUNET_free (neighbor->direct_route);
neighbor->direct_route = NULL;
}
if (NULL != neighbor->neighbor_table_consensus)
{
GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table_consensus,
&free_targets,
NULL);
GNUNET_CONTAINER_multipeermap_destroy (neighbor->neighbor_table_consensus);
neighbor->neighbor_table_consensus = NULL;
}
if (NULL != neighbor->neighbor_table)
{
GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table,
&free_targets,
NULL);
GNUNET_CONTAINER_multipeermap_destroy (neighbor->neighbor_table);
neighbor->neighbor_table = NULL;
}
if (NULL != neighbor->set_op)
{
GNUNET_SET_operation_cancel (neighbor->set_op);
neighbor->set_op = NULL;
}
if (NULL != neighbor->my_set)
{
GNUNET_SET_destroy (neighbor->my_set);
neighbor->my_set = NULL;
}
if (NULL != neighbor->listen_handle)
{
GNUNET_SET_listen_cancel (neighbor->listen_handle);
neighbor->listen_handle = NULL;
}
if (NULL != neighbor->initiate_task)
{
GNUNET_SCHEDULER_cancel (neighbor->initiate_task);
neighbor->initiate_task = NULL;
}
}
/**
* Function that is called with QoS information about an address; used
* to update our current distance to another peer.
*
* @param cls closure
* @param address the address
* @param active #GNUNET_YES if this address is actively used
* to maintain a connection to a peer;
* #GNUNET_NO if the address is not actively used;
* #GNUNET_SYSERR if this address is no longer available for ATS
* @param bandwidth_out assigned outbound bandwidth for the connection
* @param bandwidth_in assigned inbound bandwidth for the connection
* @param prop performance data for the address (as far as known)
*/
static void
handle_ats_update (void *cls,
const struct GNUNET_HELLO_Address *address,
int active,
struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out,
struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
const struct GNUNET_ATS_Properties *prop)
{
struct DirectNeighbor *neighbor;
uint32_t distance;
enum GNUNET_NetworkType network;
if (NULL == address)
{
/* ATS service temporarily disconnected */
return;
}
if (GNUNET_YES != active)
{
// FIXME: handle disconnect/inactive case too!
return;
}
distance = prop->distance;
network = prop->scope;
GNUNET_break (GNUNET_NT_UNSPECIFIED != network);
/* check if entry exists */
neighbor = GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
&address->peer);
if (NULL != neighbor)
{
neighbor->network = network;
if (neighbor->distance == distance)
return; /* nothing new to see here, move along */
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"ATS says distance to %s is now %u\n",
GNUNET_i2s (&address->peer),
(unsigned int) distance);
if ( (DIRECT_NEIGHBOR_COST == neighbor->distance) &&
(DIRECT_NEIGHBOR_COST == distance) )
return; /* no change */
if (DIRECT_NEIGHBOR_COST == neighbor->distance)
{
neighbor->distance = distance;
GNUNET_STATISTICS_update (stats,
"# peers connected (1-hop)",
-1, GNUNET_NO);
handle_direct_disconnect (neighbor);
schedule_refresh_routes ();
return;
}
neighbor->distance = distance;
if (DIRECT_NEIGHBOR_COST != neighbor->distance)
return;
if (GNUNET_YES != neighbor->connected)
return;
handle_direct_connect (neighbor);
return;
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"ATS says distance to %s is now %u\n",
GNUNET_i2s (&address->peer),
(unsigned int) distance);
neighbor = GNUNET_new (struct DirectNeighbor);
neighbor->peer = address->peer;
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_put (direct_neighbors,
&neighbor->peer,
neighbor,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
neighbor->connected = GNUNET_NO; /* not yet */
neighbor->distance = distance;
neighbor->network = network;
}
/**
* Check if a target was removed from the set of the other peer; if so,
* if we also used it for our route, we need to remove it from our
* 'all_routes' set (and later check if an alternative path now exists).
*
* @param cls the `struct DirectNeighbor`
* @param key peer identity for the target
* @param value a `struct Target` previously reachable via the given neighbor
*/
static int
check_target_removed (void *cls,
const struct GNUNET_PeerIdentity *key,
void *value)
{
struct DirectNeighbor *neighbor = cls;
struct Target *new_target;
struct Route *current_route;
new_target = GNUNET_CONTAINER_multipeermap_get (neighbor->neighbor_table_consensus,
key);
current_route = GNUNET_CONTAINER_multipeermap_get (all_routes,
key);
if (NULL != new_target)
{
/* target was in old set, is in new set */
if ( (NULL != current_route) &&
(current_route->next_hop == neighbor) &&
(current_route->target.distance != new_target->distance) )
{
/* need to recalculate routes due to distance change */
neighbor->target_removed = GNUNET_YES;
}
return GNUNET_OK;
}
/* target was revoked, check if it was used */
if ( (NULL == current_route) ||
(current_route->next_hop != neighbor) )
{
/* didn't matter, wasn't used */
return GNUNET_OK;
}
/* remove existing route */
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Lost route to %s\n",
GNUNET_i2s (¤t_route->target.peer));
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_remove (all_routes, key, current_route));
send_disconnect_to_plugin (¤t_route->target.peer);
release_route (current_route);
GNUNET_free (current_route);
neighbor->target_removed = GNUNET_YES;
return GNUNET_OK;
}
/**
* Check if a target was added to the set of the other peer; if it
* was added or impoves the existing route, do the needed updates.
*
* @param cls the `struct DirectNeighbor`
* @param key peer identity for the target
* @param value a `struct Target` now reachable via the given neighbor
*/
static int
check_target_added (void *cls,
const struct GNUNET_PeerIdentity *key,
void *value)
{
struct DirectNeighbor *neighbor = cls;
struct Target *target = value;
struct Route *current_route;
/* target was revoked, check if it was used */
current_route = GNUNET_CONTAINER_multipeermap_get (all_routes,
key);
if (NULL != current_route)
{
/* route exists */
if (current_route->next_hop == neighbor)
{
/* we had the same route before, no change in target */
if (ntohl (target->distance) + 1 != ntohl (current_route->target.distance))
{
/* but distance changed! */
if (ntohl (target->distance) + 1 > DEFAULT_FISHEYE_DEPTH)
{
/* distance increased beyond what is allowed, kill route */
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_remove (all_routes,
key,
current_route));
send_disconnect_to_plugin (key);
release_route (current_route);
GNUNET_free (current_route);
}
else
{
/* distance decreased, update route */
move_route (current_route,
ntohl (target->distance) + 1);
send_distance_change_to_plugin (&target->peer,
ntohl (target->distance) + 1,
neighbor->network);
}
}
return GNUNET_OK;
}
if (ntohl (current_route->target.distance) <= ntohl (target->distance) + 1)
{
/* alternative, shorter route exists, ignore */
return GNUNET_OK;
}
/* new route is better than the existing one, take over! */
/* NOTE: minor security issue: malicious peers may advertise
very short routes to take over longer paths; as we don't
check that the shorter routes actually work, a malicious
direct neighbor can use this to DoS our long routes */
move_route (current_route, ntohl (target->distance) + 1);
current_route->next_hop = neighbor;
send_distance_change_to_plugin (&target->peer,
ntohl (target->distance) + 1,
neighbor->network);
return GNUNET_OK;
}
/* new route */
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Discovered new route to %s using %u hops\n",
GNUNET_i2s (&target->peer),
(unsigned int) (ntohl (target->distance) + 1));
current_route = GNUNET_new (struct Route);
current_route->next_hop = neighbor;
current_route->target.peer = target->peer;
allocate_route (current_route, ntohl (target->distance) + 1);
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_put (all_routes,
¤t_route->target.peer,
current_route,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
send_connect_to_plugin (¤t_route->target.peer,
ntohl (current_route->target.distance),
neighbor->network);
return GNUNET_OK;
}
/**
* Callback for set operation results. Called for each element
* in the result set.
* We have learned a new route from the other peer. Add it to the
* route set we're building.
*
* @param cls the `struct DirectNeighbor` we're building the consensus with
* @param element a result element, only valid if status is #GNUNET_SET_STATUS_OK
* @param current_size current set size
* @param status see `enum GNUNET_SET_Status`
*/
static void
handle_set_union_result (void *cls,
const struct GNUNET_SET_Element *element,
uint64_t current_size,
enum GNUNET_SET_Status status)
{
struct DirectNeighbor *neighbor = cls;
struct DirectNeighbor *dn;
struct Target *target;
const struct Target *ctarget;
char *status_str;
switch (status)
{
case GNUNET_SET_STATUS_OK:
status_str = "GNUNET_SET_STATUS_OK";
break;
case GNUNET_SET_STATUS_FAILURE:
status_str = "GNUNET_SET_STATUS_FAILURE";
break;
case GNUNET_SET_STATUS_HALF_DONE:
status_str = "GNUNET_SET_STATUS_HALF_DONE";
break;
case GNUNET_SET_STATUS_DONE:
status_str = "GNUNET_SET_STATUS_DONE";
break;
default:
status_str = "UNDEFINED";
break;
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Got SET union result: %s\n",
status_str);
switch (status)
{
case GNUNET_SET_STATUS_OK:
if (sizeof (struct Target) != element->size)
{
GNUNET_break_op (0);
return;
}
ctarget = element->data;
if ( (NULL !=
(dn = GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
&ctarget->peer))) &&
(DIRECT_NEIGHBOR_COST == dn->distance) )
{
/* this is a direct neighbor of ours, we do not care about routes
to this peer */
return;
}
target = GNUNET_new (struct Target);
GNUNET_memcpy (target, element->data, sizeof (struct Target));
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Received information about peer `%s' with distance %u from SET\n",
GNUNET_i2s (&target->peer),
ntohl (target->distance) + 1);
if (NULL == neighbor->neighbor_table_consensus)
neighbor->neighbor_table_consensus
= GNUNET_CONTAINER_multipeermap_create (10, GNUNET_NO);
if (GNUNET_YES !=
GNUNET_CONTAINER_multipeermap_put (neighbor->neighbor_table_consensus,
&target->peer,
target,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
{
GNUNET_break_op (0);
GNUNET_free (target);
}
break;
case GNUNET_SET_STATUS_FAILURE:
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Failed to establish DV union, will try again later\n");
neighbor->set_op = NULL;
if (NULL != neighbor->neighbor_table_consensus)
{
GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table_consensus,
&free_targets,
NULL);
GNUNET_CONTAINER_multipeermap_destroy (neighbor->neighbor_table_consensus);
neighbor->neighbor_table_consensus = NULL;
}
if (0 < memcmp (&neighbor->peer,
&my_identity,
sizeof (struct GNUNET_PeerIdentity)))
neighbor->initiate_task = GNUNET_SCHEDULER_add_delayed (GNUNET_DV_CONSENSUS_FREQUENCY,
&initiate_set_union,
neighbor);
break;
case GNUNET_SET_STATUS_HALF_DONE:
break;
case GNUNET_SET_STATUS_DONE:
/* we got all of our updates; integrate routing table! */
neighbor->target_removed = GNUNET_NO;
if (NULL == neighbor->neighbor_table_consensus)
neighbor->neighbor_table_consensus = GNUNET_CONTAINER_multipeermap_create (10, GNUNET_NO);
if (NULL != neighbor->neighbor_table)
GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table,
&check_target_removed,
neighbor);
if (GNUNET_YES == neighbor->target_removed)
{
/* check if we got an alternative for the removed routes */
schedule_refresh_routes ();
}
/* add targets that appeared (and check for improved routes) */
GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table_consensus,
&check_target_added,
neighbor);
if (NULL != neighbor->neighbor_table)
{
GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table,
&free_targets,
NULL);
GNUNET_CONTAINER_multipeermap_destroy (neighbor->neighbor_table);
neighbor->neighbor_table = NULL;
}
neighbor->neighbor_table = neighbor->neighbor_table_consensus;
neighbor->neighbor_table_consensus = NULL;
/* operation done, schedule next run! */
neighbor->set_op = NULL;
if (0 < memcmp (&neighbor->peer,
&my_identity,
sizeof (struct GNUNET_PeerIdentity)))
neighbor->initiate_task = GNUNET_SCHEDULER_add_delayed (GNUNET_DV_CONSENSUS_FREQUENCY,
&initiate_set_union,
neighbor);
break;
default:
GNUNET_break (0);
return;
}
}
/**
* Start creating a new DV set union construction, our neighbour has
* asked for it (callback for listening peer).
*
* @param cls the 'struct DirectNeighbor' of the peer we're building
* a routing consensus with
* @param other_peer the other peer
* @param context_msg message with application specific information from
* the other peer
* @param request request from the other peer, use GNUNET_SET_accept
* to accept it, otherwise the request will be refused
* Note that we don't use a return value here, as it is also
* necessary to specify the set we want to do the operation with,
* whith sometimes can be derived from the context message.
* Also necessary to specify the timeout.
*/
static void
listen_set_union (void *cls,
const struct GNUNET_PeerIdentity *other_peer,
const struct GNUNET_MessageHeader *context_msg,
struct GNUNET_SET_Request *request)
{
struct DirectNeighbor *neighbor = cls;
if (NULL == request)
return; /* why??? */
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Starting to create consensus with %s\n",
GNUNET_i2s (&neighbor->peer));
if (NULL != neighbor->set_op)
{
GNUNET_SET_operation_cancel (neighbor->set_op);
neighbor->set_op = NULL;
}
if (NULL != neighbor->my_set)
{
GNUNET_SET_destroy (neighbor->my_set);
neighbor->my_set = NULL;
}
neighbor->my_set = GNUNET_SET_create (cfg,
GNUNET_SET_OPERATION_UNION);
neighbor->set_op = GNUNET_SET_accept (request,
GNUNET_SET_RESULT_ADDED,
(struct GNUNET_SET_Option[]) {{ 0 }},
&handle_set_union_result,
neighbor);
neighbor->consensus_insertion_offset = 0;
neighbor->consensus_insertion_distance = 0;
neighbor->consensus_elements = 0;
build_set (neighbor);
}
/**
* Start creating a new DV set union by initiating the connection.
*
* @param cls the `struct DirectNeighbor *` of the peer we're building
* a routing consensus with
*/
static void
initiate_set_union (void *cls)
{
struct DirectNeighbor *neighbor = cls;
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Initiating SET union with peer `%s'\n",
GNUNET_i2s (&neighbor->peer));
neighbor->initiate_task = NULL;
neighbor->my_set = GNUNET_SET_create (cfg,
GNUNET_SET_OPERATION_UNION);
neighbor->set_op = GNUNET_SET_prepare (&neighbor->peer,
&neighbor->real_session_id,
NULL,
GNUNET_SET_RESULT_ADDED,
(struct GNUNET_SET_Option[]) {{ 0 }},
&handle_set_union_result,
neighbor);
neighbor->consensus_insertion_offset = 0;
neighbor->consensus_insertion_distance = 0;
neighbor->consensus_elements = 0;
build_set (neighbor);
}
/**
* Check that @a rm is well-formed.
*
* @param cls closure
* @param rm the message
* @return #GNUNET_OK if @a rm is well-formed.
*/
static int
check_dv_route_message (void *cls,
const struct RouteMessage *rm)
{
const struct GNUNET_MessageHeader *payload;
if (ntohs (rm->header.size) < sizeof (struct RouteMessage) + sizeof (struct GNUNET_MessageHeader))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
payload = (const struct GNUNET_MessageHeader *) &rm[1];
if (ntohs (rm->header.size) != sizeof (struct RouteMessage) + ntohs (payload->size))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
/**
* Core handler for DV data messages. Whatever this message
* contains all we really have to do is rip it out of its
* DV layering and give it to our pal the DV plugin to report
* in with.
*
* @param cls closure
* @param rm the message
*/
static void
handle_dv_route_message (void *cls,
const struct RouteMessage *rm)
{
struct DirectNeighbor *neighbor = cls;
const struct GNUNET_MessageHeader *payload;
struct Route *route;
struct DirectNeighbor *nneighbor;
struct DirectNeighbor *dn;
struct Target *target;
uint32_t distance;
char me[5];
char src[5];
char prev[5];
char dst[5];
distance = ntohl (rm->distance);
payload = (const struct GNUNET_MessageHeader *) &rm[1];
strncpy (prev, GNUNET_i2s (&neighbor->peer), 4);
strncpy (me, GNUNET_i2s (&my_identity), 4);
strncpy (src, GNUNET_i2s (&rm->sender), 4);
strncpy (dst, GNUNET_i2s (&rm->target), 4);
prev[4] = me[4] = src[4] = dst[4] = '\0';
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Handling DV message with %u bytes payload of type %u from %s to %s routed by %s to me (%s @ hop %u)\n",
(unsigned int) (ntohs (rm->header.size) - sizeof (struct RouteMessage)),
ntohs (payload->type),
src,
dst,
prev,
me,
(unsigned int) distance + 1);
if (0 == memcmp (&rm->target,
&my_identity,
sizeof (struct GNUNET_PeerIdentity)))
{
if ((NULL !=
(dn = GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
&rm->sender))) &&
(DIRECT_NEIGHBOR_COST == dn->distance))
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Discarding DV message, as %s is a direct neighbor\n",
GNUNET_i2s (&rm->sender));
GNUNET_STATISTICS_update (stats,
"# messages discarded (direct neighbor)",
1, GNUNET_NO);
return;
}
/* message is for me, check reverse route! */
route = GNUNET_CONTAINER_multipeermap_get (all_routes,
&rm->sender);
if ( (NULL == route) &&
(distance < DEFAULT_FISHEYE_DEPTH) )
{
/* don't have reverse route yet, learn it! */
target = GNUNET_new (struct Target);
target->peer = rm->sender;
target->distance = htonl (distance);
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Learning sender %s at distance %u from delivery!\n",
GNUNET_i2s (&rm->sender),
(unsigned int) distance + 1);
if (NULL == neighbor->neighbor_table)
neighbor->neighbor_table = GNUNET_CONTAINER_multipeermap_create (10, GNUNET_NO);
if (GNUNET_YES !=
GNUNET_CONTAINER_multipeermap_put (neighbor->neighbor_table,
&target->peer,
target,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
{
GNUNET_break_op (0);
GNUNET_free (target);
return;
}
add_new_route (target, neighbor);
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Delivering %u bytes from %s to myself!\n",
ntohs (payload->size),
GNUNET_i2s (&rm->sender));
send_data_to_plugin (payload,
&rm->sender,
1 + distance);
return;
}
if ( (NULL == GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
&rm->sender)) &&
(NULL == GNUNET_CONTAINER_multipeermap_get (all_routes,
&rm->sender)) )
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Learning sender %s at distance %u from forwarding!\n",
GNUNET_i2s (&rm->sender),
1 + distance);
target = GNUNET_new (struct Target);
target->peer = rm->sender;
target->distance = htonl (distance);
if (NULL == neighbor->neighbor_table)
neighbor->neighbor_table = GNUNET_CONTAINER_multipeermap_create (10, GNUNET_NO);
if (GNUNET_YES !=
GNUNET_CONTAINER_multipeermap_put (neighbor->neighbor_table,
&target->peer,
target,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
{
GNUNET_break_op (0);
GNUNET_free (target);
return;
}
add_new_route (target, neighbor);
}
route = GNUNET_CONTAINER_multipeermap_get (all_routes,
&rm->target);
if (NULL == route)
{
nneighbor = GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
&rm->target);
if (NULL == nneighbor)
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"No route to %s, not routing %u bytes!\n",
GNUNET_i2s (&rm->target),
ntohs (payload->size));
GNUNET_STATISTICS_update (stats,
"# messages discarded (no route)",
1, GNUNET_NO);
return;
}
}
else
{
nneighbor = route->next_hop;
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Forwarding message to %s\n",
GNUNET_i2s (&nneighbor->peer));
forward_payload (nneighbor,
distance + 1,
&rm->sender,
&rm->target,
payload);
}
/**
* Check that @a msg is well-formed
*
* @param cls identification of the client
* @param message the actual message
* @return #GNUNET_OK if @a msg is well-formed
*/
static int
check_dv_send_message (void *cls,
const struct GNUNET_DV_SendMessage *msg)
{
const struct GNUNET_MessageHeader *payload;
if (ntohs (msg->header.size) < sizeof (struct GNUNET_DV_SendMessage) +
sizeof (struct GNUNET_MessageHeader))
{
GNUNET_break (0);
return GNUNET_SYSERR;
}
payload = (const struct GNUNET_MessageHeader *) &msg[1];
if (ntohs (msg->header.size) != sizeof (struct GNUNET_DV_SendMessage) + ntohs (payload->size))
{
GNUNET_break (0);
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
/**
* Service server's handler for message send requests (which come
* bubbling up to us through the DV plugin).
*
* @param cls identification of the client
* @param message the actual message
*/
static void
handle_dv_send_message (void *cls,
const struct GNUNET_DV_SendMessage *msg)
{
struct GNUNET_SERVICE_Client *client = cls;
struct Route *route;
const struct GNUNET_MessageHeader *payload;
payload = (const struct GNUNET_MessageHeader *) &msg[1];
route = GNUNET_CONTAINER_multipeermap_get (all_routes,
&msg->target);
if (NULL == route)
{
/* got disconnected */
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"No route to %s, dropping local message of type %u\n",
GNUNET_i2s (&msg->target),
ntohs (payload->type));
GNUNET_STATISTICS_update (stats,
"# local messages discarded (no route)",
1, GNUNET_NO);
GNUNET_SERVICE_client_continue (client);
return;
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Forwarding %u bytes of type %u to %s\n",
ntohs (payload->size),
ntohs (payload->type),
GNUNET_i2s (&msg->target));
forward_payload (route->next_hop,
0 /* first hop, distance is zero */,
&my_identity,
&msg->target,
payload);
GNUNET_SERVICE_client_continue (client);
}
/**
* Cleanup all of the data structures associated with a given neighbor.
*
* @param neighbor neighbor to clean up
*/
static void
cleanup_neighbor (struct DirectNeighbor *neighbor)
{
handle_direct_disconnect (neighbor);
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_remove (direct_neighbors,
&neighbor->peer,
neighbor));
GNUNET_free (neighbor);
}
/**
* Method called whenever a given peer disconnects.
*
* @param cls closure
* @param peer peer identity this notification is about
* @param internal_cls the corresponding `struct DirectNeighbor`
*/
static void
handle_core_disconnect (void *cls,
const struct GNUNET_PeerIdentity *peer,
void *internal_cls)
{
struct DirectNeighbor *neighbor = internal_cls;
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Received core peer disconnect message for peer `%s'!\n",
GNUNET_i2s (peer));
/* Check for disconnect from self message */
if (NULL == neighbor)
return;
GNUNET_break (GNUNET_YES == neighbor->connected);
neighbor->connected = GNUNET_NO;
if (DIRECT_NEIGHBOR_COST == neighbor->distance)
{
GNUNET_STATISTICS_update (stats,
"# peers connected (1-hop)",
-1,
GNUNET_NO);
}
cleanup_neighbor (neighbor);
if (GNUNET_YES == in_shutdown)
return;
schedule_refresh_routes ();
}
/**
* Multipeermap iterator for freeing routes. Should never be called.
*
* @param cls NULL
* @param key key value stored under
* @param value the route to be freed
* @return #GNUNET_YES to continue iteration, #GNUNET_NO to stop
*/
static int
free_route (void *cls,
const struct GNUNET_PeerIdentity *key,
void *value)
{
struct Route *route = value;
GNUNET_break (0);
GNUNET_assert (GNUNET_YES ==
GNUNET_CONTAINER_multipeermap_remove (all_routes, key, value));
release_route (route);
send_disconnect_to_plugin (&route->target.peer);
GNUNET_free (route);
return GNUNET_YES;
}
/**
* Multipeermap iterator for freeing direct neighbors. Should never be called.
*
* @param cls NULL
* @param key key value stored under
* @param value the direct neighbor to be freed
* @return #GNUNET_YES to continue iteration, #GNUNET_NO to stop
*/
static int
free_direct_neighbors (void *cls,
const struct GNUNET_PeerIdentity *key,
void *value)
{
struct DirectNeighbor *neighbor = value;
cleanup_neighbor (neighbor);
return GNUNET_YES;
}
/**
* Task run during shutdown.
*
* @param cls unused
*/
static void
shutdown_task (void *cls)
{
unsigned int i;
in_shutdown = GNUNET_YES;
GNUNET_assert (NULL != core_api);
GNUNET_CORE_disconnect (core_api);
core_api = NULL;
GNUNET_ATS_performance_done (ats);
ats = NULL;
GNUNET_CONTAINER_multipeermap_iterate (direct_neighbors,
&free_direct_neighbors,
NULL);
GNUNET_CONTAINER_multipeermap_iterate (all_routes,
&free_route,
NULL);
GNUNET_CONTAINER_multipeermap_destroy (direct_neighbors);
GNUNET_CONTAINER_multipeermap_destroy (all_routes);
GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
stats = NULL;
GNUNET_notification_context_destroy (nc);
nc = NULL;
for (i=0;idistance = htonl (route->target.distance);
cm->peer = route->target.peer;
GNUNET_MQ_send (GNUNET_SERVICE_client_get_mq (client),
env);
return GNUNET_OK;
}
/**
* Handle START-message. This is the first message sent to us
* by the client (can only be one!).
*
* @param cls closure (always NULL)
* @param client identification of the client
* @param message the actual message
*/
static void
handle_start (void *cls,
const struct GNUNET_MessageHeader *message)
{
struct GNUNET_SERVICE_Client *client = cls;
GNUNET_notification_context_add (nc,
GNUNET_SERVICE_client_get_mq (client));
GNUNET_SERVICE_client_continue (client);
GNUNET_CONTAINER_multipeermap_iterate (all_routes,
¬ify_client_about_route,
client);
}
/**
* Called on core init.
*
* @param cls unused
* @param identity this peer's identity
*/
static void
core_init (void *cls,
const struct GNUNET_PeerIdentity *identity)
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"I am peer: %s\n",
GNUNET_i2s (identity));
my_identity = *identity;
}
/**
* Process dv requests.
*
* @param cls closure
* @param c configuration to use
* @param service the initialized service
*/
static void
run (void *cls,
const struct GNUNET_CONFIGURATION_Handle *c,
struct GNUNET_SERVICE_Handle *service)
{
struct GNUNET_MQ_MessageHandler core_handlers[] = {
GNUNET_MQ_hd_var_size (dv_route_message,
GNUNET_MESSAGE_TYPE_DV_ROUTE,
struct RouteMessage,
NULL),
GNUNET_MQ_handler_end ()
};
in_shutdown = GNUNET_NO;
cfg = c;
direct_neighbors = GNUNET_CONTAINER_multipeermap_create (128,
GNUNET_NO);
all_routes = GNUNET_CONTAINER_multipeermap_create (65536,
GNUNET_NO);
core_api = GNUNET_CORE_connect (cfg,
NULL,
&core_init,
&handle_core_connect,
&handle_core_disconnect,
core_handlers);
if (NULL == core_api)
return;
ats = GNUNET_ATS_performance_init (cfg,
&handle_ats_update,
NULL);
if (NULL == ats)
{
GNUNET_CORE_disconnect (core_api);
core_api = NULL;
return;
}
nc = GNUNET_notification_context_create (MAX_QUEUE_SIZE_PLUGIN);
stats = GNUNET_STATISTICS_create ("dv",
cfg);
GNUNET_SCHEDULER_add_shutdown (&shutdown_task,
NULL);
}
/**
* Callback called when a client connects to the service.
*
* @param cls closure for the service
* @param c the new client that connected to the service
* @param mq the message queue used to send messages to the client
* @return @a c
*/
static void *
client_connect_cb (void *cls,
struct GNUNET_SERVICE_Client *c,
struct GNUNET_MQ_Handle *mq)
{
return c;
}
/**
* Callback called when a client disconnected from the service
*
* @param cls closure for the service
* @param c the client that disconnected
* @param internal_cls should be equal to @a c
*/
static void
client_disconnect_cb (void *cls,
struct GNUNET_SERVICE_Client *c,
void *internal_cls)
{
GNUNET_assert (c == internal_cls);
}
/**
* Define "main" method using service macro.
*/
GNUNET_SERVICE_MAIN
("dv",
GNUNET_SERVICE_OPTION_NONE,
&run,
&client_connect_cb,
&client_disconnect_cb,
NULL,
GNUNET_MQ_hd_fixed_size (start,
GNUNET_MESSAGE_TYPE_DV_START,
struct GNUNET_MessageHeader,
NULL),
GNUNET_MQ_hd_var_size (dv_send_message,
GNUNET_MESSAGE_TYPE_DV_SEND,
struct GNUNET_DV_SendMessage,
NULL),
GNUNET_MQ_handler_end ());
/* end of gnunet-service-dv.c */