aboutsummaryrefslogtreecommitdiff
path: root/src/consensus/gnunet-service-consensus.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/consensus/gnunet-service-consensus.c')
-rw-r--r--src/consensus/gnunet-service-consensus.c1835
1 files changed, 1835 insertions, 0 deletions
diff --git a/src/consensus/gnunet-service-consensus.c b/src/consensus/gnunet-service-consensus.c
new file mode 100644
index 0000000..1cbb9d0
--- /dev/null
+++ b/src/consensus/gnunet-service-consensus.c
@@ -0,0 +1,1835 @@
+/*
+ This file is part of GNUnet
+ (C) 2012 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 2, 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING. If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+*/
+
+
+/**
+ * @file consensus/gnunet-service-consensus.c
+ * @brief
+ * @author Florian Dold
+ */
+
+#include "platform.h"
+#include "gnunet_common.h"
+#include "gnunet_protocols.h"
+#include "gnunet_applications.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_consensus_service.h"
+#include "gnunet_core_service.h"
+#include "gnunet_stream_lib.h"
+#include "consensus_protocol.h"
+#include "ibf.h"
+#include "consensus.h"
+
+
+/**
+ * Number of IBFs in a strata estimator.
+ */
+#define STRATA_COUNT 32
+/**
+ * Number of buckets per IBF.
+ */
+#define STRATA_IBF_BUCKETS 80
+/**
+ * hash num parameter of the IBF
+ */
+#define STRATA_HASH_NUM 3
+/**
+ * Number of strata that can be transmitted in one message.
+ */
+#define STRATA_PER_MESSAGE ((1<<15) / (IBF_BUCKET_SIZE * STRATA_IBF_BUCKETS))
+
+#define BUCKETS_PER_MESSAGE ((1<<15) / IBF_BUCKET_SIZE)
+
+#define MAX_IBF_ORDER (64)
+
+
+/* forward declarations */
+
+struct ConsensusSession;
+struct IncomingSocket;
+struct ConsensusPeerInformation;
+
+static void
+send_next (struct ConsensusSession *session);
+
+static void
+write_strata (void *cls, enum GNUNET_STREAM_Status status, size_t size);
+
+static void
+write_ibf (void *cls, enum GNUNET_STREAM_Status status, size_t size);
+
+static void
+write_values (void *cls, enum GNUNET_STREAM_Status status, size_t size);
+
+static int
+get_peer_idx (const struct GNUNET_PeerIdentity *peer, const struct ConsensusSession *session);
+
+
+/**
+ * An element that is waiting to be transmitted to a client.
+ */
+struct PendingElement
+{
+ /**
+ * Pending elements are kept in a DLL.
+ */
+ struct PendingElement *next;
+
+ /**
+ * Pending elements are kept in a DLL.
+ */
+ struct PendingElement *prev;
+
+ /**
+ * The actual element
+ */
+ struct GNUNET_CONSENSUS_Element *element;
+
+ /* peer this element is coming from */
+ struct ConsensusPeerInformation *cpi;
+};
+
+struct ConsensusPeerInformation
+{
+ struct GNUNET_STREAM_Socket *socket;
+
+ /**
+ * Is socket's connection established, i.e. can we write to it?
+ * Only relevent on outgoing cpi.
+ */
+ int is_connected;
+
+ /**
+ * Type of the peer in the all-to-all rounds,
+ * GNUNET_YES if we initiate reconciliation.
+ */
+ int is_outgoing;
+
+ /**
+ * Did we receive/send a consensus hello?
+ */
+ int hello;
+
+ /**
+ * Handle for currently active read
+ */
+ struct GNUNET_STREAM_ReadHandle *rh;
+
+ /**
+ * Handle for currently active read
+ */
+ struct GNUNET_STREAM_WriteHandle *wh;
+
+ /**
+ * How many of the strate in the ibf were
+ * sent or received in this round?
+ */
+ int strata_counter;
+
+ int ibf_order;
+
+ struct InvertibleBloomFilter *outgoing_ibf;
+
+ int outgoing_bucket_counter;
+
+ struct InvertibleBloomFilter *incoming_ibf;
+
+ int incoming_bucket_counter;
+
+ /**
+ * NULL or incoming_ibf - outgoing_ibf.
+ * Decoded values of side '1' are to be requested from the the peer.
+ */
+ struct InvertibleBloomFilter *diff_ibf;
+
+ /**
+ * Strata estimator of the peer, NULL if our peer
+ * initiated the reconciliation.
+ */
+ struct InvertibleBloomFilter **strata;
+
+ unsigned int diff;
+
+ struct GNUNET_SERVER_MessageStreamTokenizer *mst;
+
+ struct ConsensusSession *session;
+};
+
+struct QueuedMessage
+{
+ struct GNUNET_MessageHeader *msg;
+
+ /**
+ * Queued messages are stored in a doubly linked list.
+ */
+ struct QueuedMessage *next;
+
+ /**
+ * Queued messages are stored in a doubly linked list.
+ */
+ struct QueuedMessage *prev;
+};
+
+
+/**
+ * A consensus session consists of one local client and the remote authorities.
+ */
+struct ConsensusSession
+{
+ /**
+ * Consensus sessions are kept in a DLL.
+ */
+ struct ConsensusSession *next;
+
+ /**
+ * Consensus sessions are kept in a DLL.
+ */
+ struct ConsensusSession *prev;
+
+ /**
+ * Join message. Used to initialize the session later,
+ * if the identity of the local peer is not yet known.
+ * NULL if the session has been fully initialized.
+ */
+ struct GNUNET_CONSENSUS_JoinMessage *join_msg;
+
+ /**
+ * Global consensus identification, computed
+ * from the local id and participating authorities.
+ */
+ struct GNUNET_HashCode global_id;
+
+ /**
+ * Local client in this consensus session.
+ * There is only one client per consensus session.
+ */
+ struct GNUNET_SERVER_Client *client;
+
+ /**
+ * Values in the consensus set of this session,
+ * all of them either have been sent by or approved by the client.
+ */
+ struct GNUNET_CONTAINER_MultiHashMap *values;
+
+ /**
+ * Elements that have not been approved (or rejected) by the client yet.
+ */
+ struct PendingElement *approval_pending_head;
+
+ /**
+ * Elements that have not been approved (or rejected) by the client yet.
+ */
+ struct PendingElement *approval_pending_tail;
+
+ struct QueuedMessage *client_messages_head;
+
+ struct QueuedMessage *client_messages_tail;
+
+ /**
+ * Currently active transmit handle for sending to the client
+ */
+ struct GNUNET_SERVER_TransmitHandle *th;
+
+ /**
+ * Once conclude_requested is GNUNET_YES, the client may not
+ * insert any more values.
+ */
+ int conclude_requested;
+
+ /**
+ * Minimum number of peers to form a consensus group
+ */
+ int conclude_group_min;
+
+ /**
+ * Current round of the conclusion
+ */
+ int current_round;
+
+ /**
+ * Soft deadline for conclude.
+ * Speed up the speed of the consensus at the cost of consensus quality, as
+ * the time approached or crosses the deadline.
+ */
+ struct GNUNET_TIME_Absolute conclude_deadline;
+
+ /**
+ * Number of other peers in the consensus
+ */
+ unsigned int num_peers;
+
+ struct ConsensusPeerInformation *info;
+
+ /**
+ * Sorted array of peer identities in this consensus session,
+ * includes the local peer.
+ */
+ struct GNUNET_PeerIdentity *peers;
+
+ /**
+ * Index of the local peer in the peers array
+ */
+ int local_peer_idx;
+
+ /**
+ * Task identifier for the round timeout task
+ */
+ GNUNET_SCHEDULER_TaskIdentifier round_timeout_tid;
+
+ struct InvertibleBloomFilter **strata;
+
+ struct InvertibleBloomFilter **ibfs;
+};
+
+
+/**
+ * Sockets from other peers who want to communicate with us.
+ * It may not be known yet which consensus session they belong to.
+ */
+struct IncomingSocket
+{
+ /**
+ * Incoming sockets are kept in a double linked list.
+ */
+ struct IncomingSocket *next;
+
+ /**
+ * Incoming sockets are kept in a double linked list.
+ */
+ struct IncomingSocket *prev;
+
+ /**
+ * The actual socket.
+ */
+ struct GNUNET_STREAM_Socket *socket;
+
+ /**
+ * Handle for currently active read
+ */
+ struct GNUNET_STREAM_ReadHandle *rh;
+
+ /**
+ * Peer that connected to us with the socket.
+ */
+ struct GNUNET_PeerIdentity *peer;
+
+ /**
+ * Message stream tokenizer for this socket.
+ */
+ struct GNUNET_SERVER_MessageStreamTokenizer *mst;
+
+ /**
+ * Peer-in-session this socket belongs to, once known, otherwise NULL.
+ */
+ struct ConsensusPeerInformation *cpi;
+};
+
+static struct IncomingSocket *incoming_sockets_head;
+static struct IncomingSocket *incoming_sockets_tail;
+
+/**
+ * Linked list of sesstions this peer participates in.
+ */
+static struct ConsensusSession *sessions_head;
+
+/**
+ * Linked list of sesstions this peer participates in.
+ */
+static struct ConsensusSession *sessions_tail;
+
+/**
+ * Configuration of the consensus service.
+ */
+static const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+/**
+ * Handle to the server for this service.
+ */
+static struct GNUNET_SERVER_Handle *srv;
+
+/**
+ * Peer that runs this service.
+ */
+static struct GNUNET_PeerIdentity *my_peer;
+
+/**
+ * Handle to the core service. Only used during service startup, will be NULL after that.
+ */
+static struct GNUNET_CORE_Handle *core;
+
+/**
+ * Listener for sockets from peers that want to reconcile with us.
+ */
+static struct GNUNET_STREAM_ListenSocket *listener;
+
+
+static void
+queue_client_message (struct ConsensusSession *session, struct GNUNET_MessageHeader *msg)
+{
+ struct QueuedMessage *qm;
+ qm = GNUNET_malloc (sizeof *qm);
+ qm->msg = msg;
+ GNUNET_CONTAINER_DLL_insert_tail (session->client_messages_head, session->client_messages_tail, qm);
+}
+
+
+static int
+estimate_difference (struct InvertibleBloomFilter** strata1,
+ struct InvertibleBloomFilter** strata2)
+{
+ int i;
+ int count;
+ count = 0;
+ for (i = STRATA_COUNT - 1; i >= 0; i--)
+ {
+ struct InvertibleBloomFilter *diff;
+ int ibf_count;
+ int more;
+ ibf_count = 0;
+ diff = ibf_dup (strata1[i]);
+ ibf_subtract (diff, strata2[i]);
+ for (;;)
+ {
+ more = ibf_decode (diff, NULL, NULL);
+ if (GNUNET_NO == more)
+ {
+ count += ibf_count;
+ break;
+ }
+ if (GNUNET_SYSERR == more)
+ {
+ return count * (1 << (i + 1));
+ }
+ ibf_count++;
+ }
+ ibf_destroy (diff);
+ }
+ return count;
+}
+
+
+
+/**
+ * Functions of this signature are called whenever data is available from the
+ * stream.
+ *
+ * @param cls the closure from GNUNET_STREAM_read
+ * @param status the status of the stream at the time this function is called
+ * @param data traffic from the other side
+ * @param size the number of bytes available in data read; will be 0 on timeout
+ * @return number of bytes of processed from 'data' (any data remaining should be
+ * given to the next time the read processor is called).
+ */
+static size_t
+session_stream_data_processor (void *cls,
+ enum GNUNET_STREAM_Status status,
+ const void *data,
+ size_t size)
+{
+ struct ConsensusPeerInformation *cpi;
+ int ret;
+
+ GNUNET_assert (GNUNET_STREAM_OK == status);
+
+ cpi = cls;
+
+ GNUNET_assert (NULL != cpi->mst);
+
+ ret = GNUNET_SERVER_mst_receive (cpi->mst, cpi, data, size, GNUNET_NO, GNUNET_YES);
+ if (GNUNET_SYSERR == ret)
+ {
+ /* FIXME: handle this correctly */
+ GNUNET_assert (0);
+ }
+
+ /* read again */
+ cpi->rh = GNUNET_STREAM_read (cpi->socket, GNUNET_TIME_UNIT_FOREVER_REL,
+ &session_stream_data_processor, cpi);
+
+ /* we always read all data */
+ return size;
+}
+
+/**
+ * Functions of this signature are called whenever data is available from the
+ * stream.
+ *
+ * @param cls the closure from GNUNET_STREAM_read
+ * @param status the status of the stream at the time this function is called
+ * @param data traffic from the other side
+ * @param size the number of bytes available in data read; will be 0 on timeout
+ * @return number of bytes of processed from 'data' (any data remaining should be
+ * given to the next time the read processor is called).
+ */
+static size_t
+incoming_stream_data_processor (void *cls,
+ enum GNUNET_STREAM_Status status,
+ const void *data,
+ size_t size)
+{
+ struct IncomingSocket *incoming;
+ int ret;
+
+ GNUNET_assert (GNUNET_STREAM_OK == status);
+
+ incoming = cls;
+
+ ret = GNUNET_SERVER_mst_receive (incoming->mst, incoming, data, size, GNUNET_NO, GNUNET_YES);
+ if (GNUNET_SYSERR == ret)
+ {
+ /* FIXME: handle this correctly */
+ GNUNET_assert (0);
+ }
+
+ /* read again */
+ incoming->rh = GNUNET_STREAM_read (incoming->socket, GNUNET_TIME_UNIT_FOREVER_REL,
+ &incoming_stream_data_processor, incoming);
+
+ /* we always read all data */
+ return size;
+}
+
+
+/**
+ * Iterator over hash map entries.
+ *
+ * @param cls closure
+ * @param key current key code
+ * @param value value in the hash map
+ * @return GNUNET_YES if we should continue to
+ * iterate,
+ * GNUNET_NO if not.
+ */
+static int
+ibf_values_iterator (void *cls,
+ const struct GNUNET_HashCode *key,
+ void *value)
+{
+ struct ConsensusPeerInformation *cpi;
+ cpi = cls;
+ ibf_insert (cpi->session->ibfs[cpi->ibf_order], key);
+ return GNUNET_YES;
+}
+
+
+static void
+create_outgoing_ibf (struct ConsensusPeerInformation *cpi)
+{
+ if (NULL == cpi->session->ibfs[cpi->ibf_order])
+ {
+ cpi->session->ibfs[cpi->ibf_order] = ibf_create (1 << cpi->ibf_order, STRATA_HASH_NUM, 0);
+ GNUNET_CONTAINER_multihashmap_iterate (cpi->session->values, ibf_values_iterator, cpi);
+ }
+ cpi->outgoing_ibf = ibf_dup (cpi->session->ibfs[cpi->ibf_order]);
+}
+
+static int
+handle_p2p_strata (struct ConsensusPeerInformation *cpi, const struct StrataMessage *strata_msg)
+{
+ int i;
+ int num_strata;
+ struct GNUNET_HashCode *hash_src;
+ uint8_t *count_src;
+
+ GNUNET_assert (GNUNET_NO == cpi->is_outgoing);
+
+ if (NULL == cpi->strata)
+ {
+ cpi->strata = GNUNET_malloc (STRATA_COUNT * sizeof (struct InvertibleBloomFilter *));
+ for (i = 0; i < STRATA_COUNT; i++)
+ cpi->strata[i] = ibf_create (STRATA_IBF_BUCKETS, STRATA_HASH_NUM, 0);
+ }
+
+ num_strata = ntohs (strata_msg->num_strata);
+
+ /* for correct message alignment, copy bucket types seperately */
+ hash_src = (struct GNUNET_HashCode *) &strata_msg[1];
+
+ for (i = 0; i < num_strata; i++)
+ {
+ memcpy (cpi->strata[cpi->strata_counter+i]->hash_sum, hash_src, STRATA_IBF_BUCKETS * sizeof *hash_src);
+ hash_src += STRATA_IBF_BUCKETS;
+ }
+
+ for (i = 0; i < num_strata; i++)
+ {
+ memcpy (cpi->strata[cpi->strata_counter+i]->id_sum, hash_src, STRATA_IBF_BUCKETS * sizeof *hash_src);
+ hash_src += STRATA_IBF_BUCKETS;
+ }
+
+ count_src = (uint8_t *) hash_src;
+
+ for (i = 0; i < num_strata; i++)
+ {
+ memcpy (cpi->strata[cpi->strata_counter+i]->count, count_src, STRATA_IBF_BUCKETS);
+ count_src += STRATA_IBF_BUCKETS;
+ }
+
+ GNUNET_assert (count_src == (((uint8_t *) &strata_msg[1]) + STRATA_IBF_BUCKETS * num_strata * IBF_BUCKET_SIZE));
+
+ cpi->strata_counter += num_strata;
+
+ if (STRATA_COUNT == cpi->strata_counter)
+ {
+
+ cpi->diff = estimate_difference (cpi->session->strata, cpi->strata);
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "received strata, diff=%d\n", cpi->diff);
+ cpi->ibf_order = 0;
+ while ((1 << cpi->ibf_order) < cpi->diff)
+ cpi->ibf_order++;
+ if (cpi->ibf_order > MAX_IBF_ORDER)
+ cpi->ibf_order = MAX_IBF_ORDER;
+ cpi->ibf_order += 2;
+ create_outgoing_ibf (cpi);
+ write_ibf (cpi, GNUNET_STREAM_OK, 0);
+ }
+
+ return GNUNET_YES;
+}
+
+
+static int
+handle_p2p_ibf (struct ConsensusPeerInformation *cpi, const struct DifferenceDigest *digest)
+{
+ struct GNUNET_HashCode *hash_src;
+ int num_buckets;
+ uint8_t *count_src;
+
+ num_buckets = (ntohs (digest->header.size) - (sizeof *digest)) / IBF_BUCKET_SIZE;
+
+ if (cpi->is_outgoing == GNUNET_YES)
+ {
+ /* we receive the ibf as an initiator, thus we're interested in the order */
+ cpi->ibf_order = digest->order;
+ if ((0 == cpi->outgoing_bucket_counter) && (NULL == cpi->wh))
+ {
+ create_outgoing_ibf (cpi);
+ write_ibf (cpi, GNUNET_STREAM_OK, 0);
+ }
+ /* FIXME: ensure that orders do not differ each time */
+ }
+ else
+ {
+ /* FIXME: handle correctly */
+ GNUNET_assert (cpi->ibf_order == digest->order);
+ }
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "receiving %d buckets at %d of %d\n", num_buckets, cpi->incoming_bucket_counter, (1 << cpi->ibf_order));
+
+ if (cpi->incoming_bucket_counter + num_buckets > (1 << cpi->ibf_order))
+ {
+ /* TODO: handle this */
+ GNUNET_assert (0);
+ }
+
+ if (NULL == cpi->incoming_ibf)
+ cpi->incoming_ibf = ibf_create (1 << cpi->ibf_order, STRATA_HASH_NUM, 0);
+
+ hash_src = (struct GNUNET_HashCode *) &digest[1];
+
+ memcpy (cpi->incoming_ibf->hash_sum, hash_src, num_buckets * sizeof *hash_src);
+ hash_src += num_buckets;
+
+ memcpy (cpi->incoming_ibf->id_sum, hash_src, num_buckets * sizeof *hash_src);
+ hash_src += num_buckets;
+
+ count_src = (uint8_t *) hash_src;
+
+ memcpy (cpi->incoming_ibf->count, count_src, num_buckets * sizeof *count_src);
+
+ cpi->incoming_bucket_counter += num_buckets;
+
+ if (cpi->incoming_bucket_counter == (1 << cpi->ibf_order))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "received full ibf\n");
+ if ((NULL == cpi->wh) && (cpi->outgoing_bucket_counter == (1 << cpi->ibf_order)))
+ write_values (cpi, GNUNET_STREAM_OK, 0);
+ }
+ return GNUNET_YES;
+}
+
+
+static int
+handle_p2p_element (struct ConsensusPeerInformation *cpi, const struct GNUNET_MessageHeader *element_msg)
+{
+ struct PendingElement *pending_element;
+ struct GNUNET_CONSENSUS_Element *element;
+ struct GNUNET_CONSENSUS_ElementMessage *client_element_msg;
+ size_t size;
+
+ size = ntohs (element_msg->size) - sizeof *element_msg;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "receiving element, size=%d\n", size);
+
+ element = GNUNET_malloc (size + sizeof *element);
+ element->size = size;
+ memcpy (&element[1], &element_msg[1], size);
+ element->data = &element[1];
+
+ pending_element = GNUNET_malloc (sizeof *pending_element);
+ pending_element->element = element;
+ GNUNET_CONTAINER_DLL_insert_tail (cpi->session->approval_pending_head, cpi->session->approval_pending_tail, pending_element);
+
+ client_element_msg = GNUNET_malloc (size + sizeof *client_element_msg);
+ client_element_msg->header.type = htons (GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_RECEIVED_ELEMENT);
+ client_element_msg->header.size = htons (size + sizeof *client_element_msg);
+ memcpy (&client_element_msg[1], &element[1], size);
+
+ queue_client_message (cpi->session, (struct GNUNET_MessageHeader *) client_element_msg);
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "received element\n");
+
+ send_next (cpi->session);
+
+ return GNUNET_YES;
+}
+
+
+static int
+handle_p2p_hello (struct IncomingSocket *inc, const struct ConsensusHello *hello)
+{
+ /* FIXME: session might not exist yet */
+ struct ConsensusSession *session;
+ session = sessions_head;
+ while (NULL != session)
+ {
+ if (0 == GNUNET_CRYPTO_hash_cmp (&session->global_id, &hello->global_id))
+ {
+ int idx;
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "peer helloed session\n");
+ idx = get_peer_idx (inc->peer, session);
+ GNUNET_assert (-1 != idx);
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "idx is %d\n", idx);
+ inc->cpi = &session->info[idx];
+ GNUNET_assert (GNUNET_NO == inc->cpi->is_outgoing);
+ inc->cpi->mst = inc->mst;
+ inc->cpi->hello = GNUNET_YES;
+ inc->cpi->socket = inc->socket;
+ return GNUNET_YES;
+ }
+ session = session->next;
+ }
+ GNUNET_assert (0);
+ return GNUNET_NO;
+}
+
+
+/**
+ * Functions with this signature are called whenever a
+ * complete message is received by the tokenizer.
+ *
+ * Do not call GNUNET_SERVER_mst_destroy in callback
+ *
+ * @param cls closure
+ * @param client identification of the client
+ * @param message the actual message
+ *
+ * @return GNUNET_OK on success, GNUNET_SYSERR to stop further processing
+ */
+static int
+mst_session_callback (void *cls, void *client, const struct GNUNET_MessageHeader *message)
+{
+ struct ConsensusPeerInformation *cpi;
+ cpi = cls;
+ switch (ntohs (message->type))
+ {
+ case GNUNET_MESSAGE_TYPE_CONSENSUS_P2P_DELTA_ESTIMATE:
+ return handle_p2p_strata (cpi, (struct StrataMessage *) message);
+ case GNUNET_MESSAGE_TYPE_CONSENSUS_P2P_DIFFERENCE_DIGEST:
+ return handle_p2p_ibf (cpi, (struct DifferenceDigest *) message);
+ case GNUNET_MESSAGE_TYPE_CONSENSUS_P2P_ELEMENTS:
+ return handle_p2p_element (cpi, message);
+ default:
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "unexpected message type from peer: %u\n", ntohs (message->type));
+ /* FIXME: handle correctly */
+ GNUNET_assert (0);
+ }
+ return GNUNET_OK;
+}
+
+
+/**
+ * Handle tokenized messages from stream sockets.
+ * Delegate them if the socket belongs to a session,
+ * handle hello messages otherwise.
+ *
+ * Do not call GNUNET_SERVER_mst_destroy in callback
+ *
+ * @param cls closure, unused
+ * @param client incoming socket this message comes from
+ * @param message the actual message
+ *
+ * @return GNUNET_OK on success, GNUNET_SYSERR to stop further processing
+ */
+static int
+mst_incoming_callback (void *cls, void *client, const struct GNUNET_MessageHeader *message)
+{
+ struct IncomingSocket *inc;
+ inc = (struct IncomingSocket *) client;
+ switch (ntohs( message->type))
+ {
+ case GNUNET_MESSAGE_TYPE_CONSENSUS_P2P_HELLO:
+ return handle_p2p_hello (inc, (struct ConsensusHello *) message);
+ default:
+ if (NULL != inc->cpi)
+ return mst_session_callback (inc->cpi, client, message);
+ /* FIXME: disconnect peer properly */
+ GNUNET_assert (0);
+ }
+ return GNUNET_OK;
+}
+
+
+/**
+ * Functions of this type are called upon new stream connection from other peers
+ * or upon binding error which happen when the app_port given in
+ * GNUNET_STREAM_listen() is already taken.
+ *
+ * @param cls the closure from GNUNET_STREAM_listen
+ * @param socket the socket representing the stream; NULL on binding error
+ * @param initiator the identity of the peer who wants to establish a stream
+ * with us; NULL on binding error
+ * @return GNUNET_OK to keep the socket open, GNUNET_SYSERR to close the
+ * stream (the socket will be invalid after the call)
+ */
+static int
+listen_cb (void *cls,
+ struct GNUNET_STREAM_Socket *socket,
+ const struct GNUNET_PeerIdentity *initiator)
+{
+ struct IncomingSocket *incoming;
+
+ GNUNET_assert (NULL != socket);
+
+ incoming = GNUNET_malloc (sizeof *incoming);
+
+ incoming->socket = socket;
+ incoming->peer = GNUNET_memdup (initiator, sizeof *initiator);
+
+ incoming->rh = GNUNET_STREAM_read (socket, GNUNET_TIME_UNIT_FOREVER_REL,
+ &incoming_stream_data_processor, incoming);
+
+
+ incoming->mst = GNUNET_SERVER_mst_create (mst_incoming_callback, incoming);
+
+ GNUNET_CONTAINER_DLL_insert_tail (incoming_sockets_head, incoming_sockets_tail, incoming);
+
+ return GNUNET_OK;
+}
+
+
+static void
+destroy_session (struct ConsensusSession *session)
+{
+ /* FIXME: more stuff to free! */
+ GNUNET_CONTAINER_DLL_remove (sessions_head, sessions_tail, session);
+ GNUNET_SERVER_client_drop (session->client);
+ GNUNET_free (session);
+}
+
+
+/**
+ * Disconnect a client, and destroy all sessions associated with it.
+ *
+ * @param client the client to disconnect
+ */
+static void
+disconnect_client (struct GNUNET_SERVER_Client *client)
+{
+ struct ConsensusSession *session;
+ GNUNET_SERVER_client_disconnect (client);
+
+ /* if the client owns a session, remove it */
+ session = sessions_head;
+ while (NULL != session)
+ {
+ if (client == session->client)
+ {
+ destroy_session (session);
+ break;
+ }
+ session = session->next;
+ }
+}
+
+
+/**
+ * Compute a global, (hopefully) unique consensus session id,
+ * from the local id of the consensus session, and the identities of all participants.
+ * Thus, if the local id of two consensus sessions coincide, but are not comprised of
+ * exactly the same peers, the global id will be different.
+ *
+ * @param local_id local id of the consensus session
+ * @param peers array of all peers participating in the consensus session
+ * @param num_peers number of elements in the peers array
+ * @param dst where the result is stored, may not be NULL
+ */
+static void
+compute_global_id (const struct GNUNET_HashCode *local_id,
+ const struct GNUNET_PeerIdentity *peers, int num_peers,
+ struct GNUNET_HashCode *dst)
+{
+ int i;
+ struct GNUNET_HashCode tmp;
+
+ *dst = *local_id;
+ for (i = 0; i < num_peers; ++i)
+ {
+ GNUNET_CRYPTO_hash_xor (dst, &peers[0].hashPubKey, &tmp);
+ *dst = tmp;
+ GNUNET_CRYPTO_hash (dst, sizeof (struct GNUNET_PeerIdentity), &tmp);
+ *dst = tmp;
+ }
+}
+
+
+/**
+ * Function called to notify a client about the connection
+ * begin ready to queue more data. "buf" will be
+ * NULL and "size" zero if the connection was closed for
+ * writing in the meantime.
+ *
+ * @param cls consensus session
+ * @param size number of bytes available in buf
+ * @param buf where the callee should write the message
+ * @return number of bytes written to buf
+ */
+static size_t
+transmit_queued (void *cls, size_t size,
+ void *buf)
+{
+ struct ConsensusSession *session;
+ struct QueuedMessage *qmsg;
+ size_t msg_size;
+
+ session = cls;
+ session->th = NULL;
+
+
+ qmsg = session->client_messages_head;
+ GNUNET_CONTAINER_DLL_remove (session->client_messages_head, session->client_messages_tail, qmsg);
+ GNUNET_assert (qmsg);
+
+ if (NULL == buf)
+ {
+ destroy_session (session);
+ return 0;
+ }
+
+ msg_size = ntohs (qmsg->msg->size);
+
+ GNUNET_assert (size >= msg_size);
+
+ memcpy (buf, qmsg->msg, msg_size);
+ GNUNET_free (qmsg->msg);
+ GNUNET_free (qmsg);
+
+ send_next (session);
+
+ return msg_size;
+}
+
+
+/**
+ * Schedule sending the next message (if there is any) to a client.
+ *
+ * @param cli the client to send the next message to
+ */
+static void
+send_next (struct ConsensusSession *session)
+{
+
+ GNUNET_assert (NULL != session);
+
+ if (NULL != session->th)
+ return;
+
+ if (NULL != session->client_messages_head)
+ {
+ int msize;
+ msize = ntohs (session->client_messages_head->msg->size);
+ session->th = GNUNET_SERVER_notify_transmit_ready (session->client, msize,
+ GNUNET_TIME_UNIT_FOREVER_REL,
+ &transmit_queued, session);
+ }
+}
+
+
+/**
+ * Although GNUNET_CRYPTO_hash_cmp exisits, it does not have
+ * the correct signature to be used with e.g. qsort.
+ * We use this function instead.
+ *
+ * @param h1 some hash code
+ * @param h2 some hash code
+ * @return 1 if h1 > h2, -1 if h1 < h2 and 0 if h1 == h2.
+ */
+static int
+hash_cmp (const void *a, const void *b)
+{
+ return GNUNET_CRYPTO_hash_cmp ((struct GNUNET_HashCode *) a, (struct GNUNET_HashCode *) b);
+}
+
+
+/**
+ * Search peer in the list of peers in session.
+ *
+ * @param peer peer to find
+ * @param session session with peer
+ * @return index of peer, -1 if peer is not in session
+ */
+static int
+get_peer_idx (const struct GNUNET_PeerIdentity *peer, const struct ConsensusSession *session)
+{
+ const struct GNUNET_PeerIdentity *needle;
+ needle = bsearch (peer, session->peers, session->num_peers, sizeof (struct GNUNET_PeerIdentity), &hash_cmp);
+ if (NULL == needle)
+ return -1;
+ return needle - session->peers;
+}
+
+
+
+static void
+hello_cont (void *cls, enum GNUNET_STREAM_Status status, size_t size)
+{
+ struct ConsensusPeerInformation *cpi;
+
+ cpi = cls;
+ cpi->hello = GNUNET_YES;
+
+ GNUNET_assert (GNUNET_STREAM_OK == status);
+
+ if (cpi->session->conclude_requested)
+ {
+ write_strata (cpi, GNUNET_STREAM_OK, 0);
+ }
+}
+
+
+/**
+ * Functions of this type will be called when a stream is established
+ *
+ * @param cls the closure from GNUNET_STREAM_open
+ * @param socket socket to use to communicate with the other side (read/write)
+ */
+static void
+open_cb (void *cls, struct GNUNET_STREAM_Socket *socket)
+{
+ struct ConsensusPeerInformation *cpi;
+ struct ConsensusHello *hello;
+
+
+ cpi = cls;
+ cpi->is_connected = GNUNET_YES;
+
+ hello = GNUNET_malloc (sizeof *hello);
+ hello->header.size = htons (sizeof *hello);
+ hello->header.type = htons (GNUNET_MESSAGE_TYPE_CONSENSUS_P2P_HELLO);
+ memcpy (&hello->global_id, &cpi->session->global_id, sizeof (struct GNUNET_HashCode));
+
+ cpi->wh =
+ GNUNET_STREAM_write (socket, hello, sizeof *hello, GNUNET_TIME_UNIT_FOREVER_REL, hello_cont, cpi);
+
+ cpi->rh = GNUNET_STREAM_read (socket, GNUNET_TIME_UNIT_FOREVER_REL,
+ &session_stream_data_processor, cpi);
+
+}
+
+
+static void
+initialize_session_info (struct ConsensusSession *session)
+{
+ int i;
+ int last;
+
+ for (i = 0; i < session->num_peers; ++i)
+ {
+ /* initialize back-references, so consensus peer information can
+ * be used as closure */
+ session->info[i].session = session;
+ }
+
+ last = (session->local_peer_idx + ((session->num_peers - 1) / 2) + 1) % session->num_peers;
+ i = (session->local_peer_idx + 1) % session->num_peers;
+ while (i != last)
+ {
+ session->info[i].is_outgoing = GNUNET_YES;
+ session->info[i].socket = GNUNET_STREAM_open (cfg, &session->peers[i], GNUNET_APPLICATION_TYPE_CONSENSUS,
+ open_cb, &session->info[i], GNUNET_STREAM_OPTION_END);
+ session->info[i].mst = GNUNET_SERVER_mst_create (mst_session_callback, &session->info[i]);
+ i = (i + 1) % session->num_peers;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "peer %d contacts peer %d\n", session->local_peer_idx, i);
+ }
+ // tie-breaker for even number of peers
+ if (((session->num_peers % 2) == 0) && (session->local_peer_idx < last))
+ {
+ session->info[last].is_outgoing = GNUNET_YES;
+ session->info[last].socket = GNUNET_STREAM_open (cfg, &session->peers[last], GNUNET_APPLICATION_TYPE_CONSENSUS,
+ open_cb, &session->info[last], GNUNET_STREAM_OPTION_END);
+ session->info[last].mst = GNUNET_SERVER_mst_create (mst_session_callback, &session->info[last]);
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "peer %d contacts peer %d (tiebreaker)\n", session->local_peer_idx, last);
+ }
+}
+
+
+/**
+ * Create the sorted list of peers for the session,
+ * add the local peer if not in the join message.
+ */
+static void
+initialize_session_peer_list (struct ConsensusSession *session)
+{
+ int local_peer_in_list;
+ int listed_peers;
+ const struct GNUNET_PeerIdentity *msg_peers;
+ unsigned int i;
+
+ GNUNET_assert (NULL != session->join_msg);
+
+ /* peers in the join message, may or may not include the local peer */
+ listed_peers = ntohs (session->join_msg->num_peers);
+
+ session->num_peers = listed_peers;
+
+ msg_peers = (struct GNUNET_PeerIdentity *) &session->join_msg[1];
+
+ local_peer_in_list = GNUNET_NO;
+ for (i = 0; i < listed_peers; i++)
+ {
+ if (0 == memcmp (&msg_peers[i], my_peer, sizeof (struct GNUNET_PeerIdentity)))
+ {
+ local_peer_in_list = GNUNET_YES;
+ break;
+ }
+ }
+
+ if (GNUNET_NO == local_peer_in_list)
+ session->num_peers++;
+
+ session->peers = GNUNET_malloc (session->num_peers * sizeof (struct GNUNET_PeerIdentity));
+
+ if (GNUNET_NO == local_peer_in_list)
+ session->peers[session->num_peers - 1] = *my_peer;
+
+ memcpy (session->peers, msg_peers, listed_peers * sizeof (struct GNUNET_PeerIdentity));
+ qsort (session->peers, session->num_peers, sizeof (struct GNUNET_PeerIdentity), &hash_cmp);
+}
+
+
+static void
+strata_insert (struct InvertibleBloomFilter **strata, struct GNUNET_HashCode *key)
+{
+ uint32_t v;
+ int i;
+ v = key->bits[0];
+ /* count trailing '1'-bits of v */
+ for (i = 0; v & 1; v>>=1, i++);
+ ibf_insert (strata[i], key);
+}
+
+
+/**
+ * Initialize the session, continue receiving messages from the owning client
+ *
+ * @param session the session to initialize
+ */
+static void
+initialize_session (struct ConsensusSession *session)
+{
+ const struct ConsensusSession *other_session;
+ int i;
+
+ GNUNET_assert (NULL != session->join_msg);
+
+ initialize_session_peer_list (session);
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "session with %u peers\n", session->num_peers);
+
+ compute_global_id (&session->join_msg->session_id, session->peers, session->num_peers, &session->global_id);
+
+ /* Check if some local client already owns the session. */
+ other_session = sessions_head;
+ while (NULL != other_session)
+ {
+ if ((other_session != session) &&
+ (0 == GNUNET_CRYPTO_hash_cmp (&session->global_id, &other_session->global_id)))
+ {
+ /* session already owned by another client */
+ GNUNET_break (0);
+ disconnect_client (session->client);
+ return;
+ }
+ other_session = other_session->next;
+ }
+
+ session->values = GNUNET_CONTAINER_multihashmap_create (256, GNUNET_NO);
+
+ session->local_peer_idx = get_peer_idx (my_peer, session);
+ GNUNET_assert (-1 != session->local_peer_idx);
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "%d is the local peer\n", session->local_peer_idx);
+
+ session->strata = GNUNET_malloc (STRATA_COUNT * sizeof (struct InvertibleBloomFilter *));
+ for (i = 0; i < STRATA_COUNT; i++)
+ session->strata[i] = ibf_create (STRATA_IBF_BUCKETS, STRATA_HASH_NUM, 0);
+
+ session->ibfs = GNUNET_malloc (MAX_IBF_ORDER * sizeof (struct InvertibleBloomFilter *));
+
+ session->info = GNUNET_malloc (session->num_peers * sizeof (struct ConsensusPeerInformation));
+ initialize_session_info (session);
+
+ GNUNET_free (session->join_msg);
+ session->join_msg = NULL;
+
+ GNUNET_SERVER_receive_done (session->client, GNUNET_OK);
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "session %s initialized\n", GNUNET_h2s (&session->global_id));
+}
+
+
+/**
+ * Called when a client wants to join a consensus session.
+ *
+ * @param cls unused
+ * @param client client that sent the message
+ * @param m message sent by the client
+ */
+static void
+client_join (void *cls,
+ struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *m)
+{
+ struct ConsensusSession *session;
+
+ // make sure the client has not already joined a session
+ session = sessions_head;
+ while (NULL != session)
+ {
+ if (session->client == client)
+ {
+ GNUNET_break (0);
+ disconnect_client (client);
+ return;
+ }
+ session = session->next;
+ }
+
+ session = GNUNET_malloc (sizeof (struct ConsensusSession));
+ session->join_msg = (struct GNUNET_CONSENSUS_JoinMessage *) GNUNET_copy_message (m);
+ session->client = client;
+ GNUNET_SERVER_client_keep (client);
+
+ GNUNET_CONTAINER_DLL_insert (sessions_head, sessions_tail, session);
+
+ // Initialize session later if local peer identity is not known yet.
+ if (NULL == my_peer)
+ {
+ GNUNET_SERVER_disable_receive_done_warning (client);
+ return;
+ }
+
+ initialize_session (session);
+}
+
+
+/**
+ * Called when a client performs an insert operation.
+ *
+ * @param cls (unused)
+ * @param client client handle
+ * @param message message sent by the client
+ */
+void
+client_insert (void *cls,
+ struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *m)
+{
+ struct ConsensusSession *session;
+ struct GNUNET_CONSENSUS_ElementMessage *msg;
+ struct GNUNET_CONSENSUS_Element *element;
+ struct GNUNET_HashCode key;
+ int element_size;
+
+ session = sessions_head;
+ while (NULL != session)
+ {
+ if (session->client == client)
+ break;
+ }
+
+ if (NULL == session)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "client tried to insert, but client is not in any session\n");
+ GNUNET_SERVER_client_disconnect (client);
+ return;
+ }
+
+ msg = (struct GNUNET_CONSENSUS_ElementMessage *) m;
+ element_size = ntohs (msg->header.size )- sizeof (struct GNUNET_CONSENSUS_ElementMessage);
+
+ element = GNUNET_malloc (sizeof (struct GNUNET_CONSENSUS_Element) + element_size);
+
+ element->type = msg->element_type;
+ element->size = element_size;
+ memcpy (&element[1], &msg[1], element_size);
+ element->data = &element[1];
+
+ GNUNET_assert (NULL != element->data);
+
+ GNUNET_CRYPTO_hash (element, element_size, &key);
+
+ GNUNET_CONTAINER_multihashmap_put (session->values, &key, element,
+ GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
+
+ strata_insert (session->strata, &key);
+
+ GNUNET_SERVER_receive_done (client, GNUNET_OK);
+
+ send_next (session);
+}
+
+
+
+/**
+ * Functions of this signature are called whenever writing operations
+ * on a stream are executed
+ *
+ * @param cls the closure from GNUNET_STREAM_write
+ * @param status the status of the stream at the time this function is called;
+ * GNUNET_STREAM_OK if writing to stream was completed successfully;
+ * GNUNET_STREAM_TIMEOUT if the given data is not sent successfully
+ * (this doesn't mean that the data is never sent, the receiver may
+ * have read the data but its ACKs may have been lost);
+ * GNUNET_STREAM_SHUTDOWN if the stream is shutdown for writing in the
+ * mean time; GNUNET_STREAM_SYSERR if the stream is broken and cannot
+ * be processed.
+ * @param size the number of bytes written
+ */
+static void
+write_strata (void *cls, enum GNUNET_STREAM_Status status, size_t size)
+{
+ struct ConsensusPeerInformation *cpi;
+ struct StrataMessage *strata_msg;
+ size_t msize;
+ int i;
+ struct GNUNET_HashCode *hash_dst;
+ uint8_t *count_dst;
+ int num_strata;
+
+ cpi = cls;
+ cpi->wh = NULL;
+
+ GNUNET_assert (GNUNET_YES == cpi->is_outgoing);
+
+ /* FIXME: handle this */
+ GNUNET_assert (GNUNET_STREAM_OK == status);
+
+ if (STRATA_COUNT == cpi->strata_counter)
+ {
+ /* strata have been written, wait for other side's IBF */
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "strata written\n");
+ return;
+ }
+
+ if ((STRATA_COUNT - cpi->strata_counter) < STRATA_PER_MESSAGE)
+ num_strata = (STRATA_COUNT - cpi->strata_counter);
+ else
+ num_strata = STRATA_PER_MESSAGE;
+
+
+ msize = (sizeof *strata_msg) + (num_strata * IBF_BUCKET_SIZE * STRATA_IBF_BUCKETS);
+
+ strata_msg = GNUNET_malloc (msize);
+ strata_msg->header.size = htons (msize);
+ strata_msg->header.type = htons (GNUNET_MESSAGE_TYPE_CONSENSUS_P2P_DELTA_ESTIMATE);
+ strata_msg->num_strata = htons (num_strata);
+
+ /* for correct message alignment, copy bucket types seperately */
+ hash_dst = (struct GNUNET_HashCode *) &strata_msg[1];
+
+ for (i = 0; i < num_strata; i++)
+ {
+ memcpy (hash_dst, cpi->session->strata[cpi->strata_counter+i]->hash_sum, STRATA_IBF_BUCKETS * sizeof *hash_dst);
+ hash_dst += STRATA_IBF_BUCKETS;
+ }
+
+ for (i = 0; i < num_strata; i++)
+ {
+ memcpy (hash_dst, cpi->session->strata[cpi->strata_counter+i]->id_sum, STRATA_IBF_BUCKETS * sizeof *hash_dst);
+ hash_dst += STRATA_IBF_BUCKETS;
+ }
+
+ count_dst = (uint8_t *) hash_dst;
+
+ for (i = 0; i < num_strata; i++)
+ {
+ memcpy (count_dst, cpi->session->strata[cpi->strata_counter+i]->count, STRATA_IBF_BUCKETS);
+ count_dst += STRATA_IBF_BUCKETS;
+ }
+
+ cpi->strata_counter += num_strata;
+
+ cpi->wh = GNUNET_STREAM_write (cpi->socket, strata_msg, msize, GNUNET_TIME_UNIT_FOREVER_REL,
+ write_strata, cpi);
+
+ GNUNET_assert (NULL != cpi->wh);
+}
+
+
+/**
+ * Functions of this signature are called whenever writing operations
+ * on a stream are executed
+ *
+ * @param cls the closure from GNUNET_STREAM_write
+ * @param status the status of the stream at the time this function is called;
+ * GNUNET_STREAM_OK if writing to stream was completed successfully;
+ * GNUNET_STREAM_TIMEOUT if the given data is not sent successfully
+ * (this doesn't mean that the data is never sent, the receiver may
+ * have read the data but its ACKs may have been lost);
+ * GNUNET_STREAM_SHUTDOWN if the stream is shutdown for writing in the
+ * mean time; GNUNET_STREAM_SYSERR if the stream is broken and cannot
+ * be processed.
+ * @param size the number of bytes written
+ */
+static void
+write_ibf (void *cls, enum GNUNET_STREAM_Status status, size_t size)
+{
+ struct ConsensusPeerInformation *cpi;
+ struct DifferenceDigest *digest;
+ int msize;
+ struct GNUNET_HashCode *hash_dst;
+ uint8_t *count_dst;
+ int num_buckets;
+
+ cpi = cls;
+ cpi->wh = NULL;
+
+ if (cpi->outgoing_bucket_counter == (1 << cpi->ibf_order))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "ibf completely written\n");
+ if (cpi->incoming_bucket_counter == (1 << cpi->ibf_order))
+ write_values (cpi, GNUNET_STREAM_OK, 0);
+ return;
+ }
+
+ /* remaining buckets */
+ num_buckets = (1 << cpi->ibf_order) - cpi->outgoing_bucket_counter;
+
+ /* limit to maximum */
+ if (num_buckets > BUCKETS_PER_MESSAGE)
+ num_buckets = BUCKETS_PER_MESSAGE;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "writing ibf buckets at %d/%d\n", cpi->outgoing_bucket_counter, (1<<cpi->ibf_order));
+
+ msize = (sizeof *digest) + (num_buckets * IBF_BUCKET_SIZE);
+
+ digest = GNUNET_malloc (msize);
+ digest->header.size = htons (msize);
+ digest->header.type = htons (GNUNET_MESSAGE_TYPE_CONSENSUS_P2P_DIFFERENCE_DIGEST);
+ digest->order = cpi->ibf_order;
+
+ hash_dst = (struct GNUNET_HashCode *) &digest[1];
+
+ memcpy (hash_dst, cpi->outgoing_ibf->hash_sum, num_buckets * sizeof *hash_dst);
+ hash_dst += num_buckets;
+
+ memcpy (hash_dst, cpi->outgoing_ibf->id_sum, num_buckets * sizeof *hash_dst);
+ hash_dst += num_buckets;
+
+ count_dst = (uint8_t *) hash_dst;
+
+ memcpy (count_dst, cpi->outgoing_ibf->count, num_buckets * sizeof *count_dst);
+
+ cpi->outgoing_bucket_counter += num_buckets;
+
+ cpi->wh = GNUNET_STREAM_write (cpi->socket, digest, msize, GNUNET_TIME_UNIT_FOREVER_REL,
+ write_ibf, cpi);
+
+ GNUNET_assert (NULL != cpi->wh);
+}
+
+
+/**
+ * Functions of this signature are called whenever writing operations
+ * on a stream are executed
+ *
+ * @param cls the closure from GNUNET_STREAM_write
+ * @param status the status of the stream at the time this function is called;
+ * GNUNET_STREAM_OK if writing to stream was completed successfully;
+ * GNUNET_STREAM_TIMEOUT if the given data is not sent successfully
+ * (this doesn't mean that the data is never sent, the receiver may
+ * have read the data but its ACKs may have been lost);
+ * GNUNET_STREAM_SHUTDOWN if the stream is shutdown for writing in the
+ * mean time; GNUNET_STREAM_SYSERR if the stream is broken and cannot
+ * be processed.
+ * @param size the number of bytes written
+ */
+static void
+write_values (void *cls, enum GNUNET_STREAM_Status status, size_t size)
+{
+ struct ConsensusPeerInformation *cpi;
+ struct GNUNET_HashCode key;
+ struct GNUNET_CONSENSUS_Element *element;
+ struct GNUNET_MessageHeader *element_msg;
+ int side;
+ int msize;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "transmitting value\n");
+
+ cpi = cls;
+ cpi->wh = NULL;
+
+ if (NULL == cpi->diff_ibf)
+ {
+ GNUNET_assert (NULL != cpi->incoming_ibf);
+ GNUNET_assert (NULL != cpi->outgoing_ibf);
+ GNUNET_assert (cpi->outgoing_ibf->size == cpi->incoming_ibf->size);
+ cpi->diff_ibf = ibf_dup (cpi->incoming_ibf);
+ ibf_subtract (cpi->diff_ibf, cpi->outgoing_ibf);
+ }
+
+ for (;;)
+ {
+ int res;
+ res = ibf_decode (cpi->diff_ibf, &side, &key);
+ if (GNUNET_SYSERR == res)
+ {
+ /* TODO: handle this correctly, request new ibf */
+ GNUNET_break (0);
+ return;
+ }
+ if (GNUNET_NO == res)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "transmitted all values\n");
+ return;
+ }
+ if (-1 == side)
+ break;
+ }
+
+ element = GNUNET_CONTAINER_multihashmap_get (cpi->session->values, &key);
+
+ if (NULL == element)
+ {
+ /* FIXME: handle correctly */
+ GNUNET_break (0);
+ return;
+ }
+
+ msize = sizeof (struct GNUNET_MessageHeader) + element->size;
+
+ element_msg = GNUNET_malloc (msize);
+ element_msg->size = htons (msize);
+ element_msg->type = htons (GNUNET_MESSAGE_TYPE_CONSENSUS_P2P_ELEMENTS);
+
+
+ GNUNET_assert (NULL != element->data);
+
+
+ memcpy (&element_msg[1], element->data, element->size);
+
+ cpi->wh = GNUNET_STREAM_write (cpi->socket, element_msg, msize, GNUNET_TIME_UNIT_FOREVER_REL,
+ write_values, cpi);
+
+ GNUNET_free (element_msg);
+
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "transmitted value\n");
+
+ GNUNET_assert (NULL != cpi->wh);
+}
+
+
+/**
+ * Called when a client performs the conclude operation.
+ *
+ * @param cls (unused)
+ * @param client client handle
+ * @param message message sent by the client
+ */
+void
+client_conclude (void *cls,
+ struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *message)
+{
+ struct ConsensusSession *session;
+ int i;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "conclude requested\n");
+
+ session = sessions_head;
+ while ((session != NULL) && (session->client != client))
+ session = session->next;
+ if (NULL == session)
+ {
+ /* client not found */
+ GNUNET_break (0);
+ GNUNET_SERVER_client_disconnect (client);
+ return;
+ }
+
+ if (GNUNET_YES == session->conclude_requested)
+ {
+ /* client requested conclude twice */
+ GNUNET_break (0);
+ disconnect_client (client);
+ return;
+ }
+
+ session->conclude_requested = GNUNET_YES;
+
+ /* FIXME: write to already connected sockets */
+
+ for (i = 0; i < session->num_peers; i++)
+ {
+ if ( (GNUNET_YES == session->info[i].is_outgoing) &&
+ (GNUNET_YES == session->info[i].hello) )
+ {
+ /* kick off transmitting strata by calling the write continuation */
+ write_strata (&session->info[i], GNUNET_STREAM_OK, 0);
+ }
+ }
+
+ GNUNET_SERVER_receive_done (client, GNUNET_OK);
+ send_next (session);
+}
+
+
+/**
+ * Called when a client sends an ack
+ *
+ * @param cls (unused)
+ * @param client client handle
+ * @param message message sent by the client
+ */
+void
+client_ack (void *cls,
+ struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *message)
+{
+ struct ConsensusSession *session;
+ struct GNUNET_CONSENSUS_AckMessage *msg;
+ struct PendingElement *pending;
+ struct GNUNET_CONSENSUS_Element *element;
+ struct GNUNET_HashCode key;
+
+ session = sessions_head;
+ while (NULL != session)
+ {
+ if (session->client == client)
+ break;
+ }
+
+ if (NULL == session)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "client tried to ack, but client is not in any session\n");
+ GNUNET_SERVER_client_disconnect (client);
+ return;
+ }
+
+ pending = session->approval_pending_head;
+
+ GNUNET_CONTAINER_DLL_remove (session->approval_pending_head, session->approval_pending_tail, pending);
+
+ msg = (struct GNUNET_CONSENSUS_AckMessage *) message;
+
+ if (msg->keep)
+ {
+
+ element = pending->element;
+
+ GNUNET_CRYPTO_hash (element, element->size, &key);
+
+ GNUNET_CONTAINER_multihashmap_put (session->values, &key, element,
+ GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
+
+ strata_insert (session->strata, &key);
+ }
+
+ /* FIXME: also remove element from strata */
+
+ GNUNET_SERVER_receive_done (client, GNUNET_OK);
+}
+
+/**
+ * Task that disconnects from core.
+ *
+ * @param cls core handle
+ * @param tc context information (why was this task triggered now)
+ */
+static void
+disconnect_core (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ GNUNET_CORE_disconnect (core);
+ core = NULL;
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "disconnected from core\n");
+}
+
+
+static void
+core_startup (void *cls,
+ struct GNUNET_CORE_Handle *core,
+ const struct GNUNET_PeerIdentity *peer)
+{
+ struct ConsensusSession *session;
+
+ my_peer = GNUNET_memdup(peer, sizeof (struct GNUNET_PeerIdentity));
+ /* core can't be disconnected directly in the core startup callback, schedule a task to do it! */
+ GNUNET_SCHEDULER_add_now (&disconnect_core, core);
+ GNUNET_log(GNUNET_ERROR_TYPE_INFO, "connected to core\n");
+
+ session = sessions_head;
+ while (NULL != session)
+ {
+ if (NULL != session->join_msg)
+ initialize_session (session);
+ session = session->next;
+ }
+}
+
+
+/**
+ * Called to clean up, after a shutdown has been requested.
+ *
+ * @param cls closure
+ * @param tc context information (why was this task triggered now)
+ */
+static void
+shutdown_task (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+
+ /* FIXME: complete; write separate destructors for different data types */
+
+ while (NULL != incoming_sockets_head)
+ {
+ struct IncomingSocket *socket;
+ socket = incoming_sockets_head;
+ if (NULL == socket->cpi)
+ {
+ GNUNET_STREAM_close (socket->socket);
+ }
+ incoming_sockets_head = incoming_sockets_head->next;
+ GNUNET_free (socket);
+ }
+
+ while (NULL != sessions_head)
+ {
+ struct ConsensusSession *session;
+ int i;
+
+ session = sessions_head;
+
+ for (i = 0; session->num_peers; i++)
+ {
+ struct ConsensusPeerInformation *cpi;
+ cpi = &session->info[i];
+ if ((NULL != cpi) && (NULL != cpi->socket))
+ {
+ GNUNET_STREAM_close (cpi->socket);
+ }
+ }
+
+ if (NULL != session->client)
+ GNUNET_SERVER_client_disconnect (session->client);
+
+ sessions_head = sessions_head->next;
+ GNUNET_free (session);
+ }
+
+ if (NULL != core)
+ {
+ GNUNET_CORE_disconnect (core);
+ core = NULL;
+ }
+
+ if (NULL != listener)
+ {
+ GNUNET_STREAM_listen_close (listener);
+ listener = NULL;
+ }
+
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "handled shutdown request\n");
+}
+
+
+/**
+ * Start processing consensus requests.
+ *
+ * @param cls closure
+ * @param server the initialized server
+ * @param c configuration to use
+ */
+static void
+run (void *cls, struct GNUNET_SERVER_Handle *server, const struct GNUNET_CONFIGURATION_Handle *c)
+{
+ static const struct GNUNET_CORE_MessageHandler core_handlers[] = {
+ {NULL, 0, 0}
+ };
+ static const struct GNUNET_SERVER_MessageHandler server_handlers[] = {
+ {&client_join, NULL, GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_JOIN, 0},
+ {&client_insert, NULL, GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_INSERT, 0},
+ {&client_conclude, NULL, GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_CONCLUDE,
+ sizeof (struct GNUNET_CONSENSUS_ConcludeMessage)},
+ {&client_ack, NULL, GNUNET_MESSAGE_TYPE_CONSENSUS_CLIENT_ACK,
+ sizeof (struct GNUNET_CONSENSUS_AckMessage)},
+ {NULL, NULL, 0, 0}
+ };
+
+ cfg = c;
+ srv = server;
+
+ GNUNET_SERVER_add_handlers (server, server_handlers);
+
+ GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task, NULL);
+
+
+ listener = GNUNET_STREAM_listen (cfg, GNUNET_APPLICATION_TYPE_CONSENSUS,
+ listen_cb, NULL,
+ GNUNET_STREAM_OPTION_END);
+
+
+ /* we have to wait for the core_startup callback before proceeding with the consensus service startup */
+ core = GNUNET_CORE_connect (c, NULL, &core_startup, NULL, NULL, NULL, GNUNET_NO, NULL, GNUNET_NO, core_handlers);
+ GNUNET_assert (NULL != core);
+
+ GNUNET_log(GNUNET_ERROR_TYPE_INFO, "consensus running\n");
+}
+
+
+/**
+ * The main function for the consensus service.
+ *
+ * @param argc number of arguments from the command line
+ * @param argv command line arguments
+ * @return 0 ok, 1 on error
+ */
+int
+main (int argc, char *const *argv)
+{
+ int ret;
+ ret = GNUNET_SERVICE_run (argc, argv, "consensus", GNUNET_SERVICE_OPTION_NONE, &run, NULL);
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "exit\n");
+ return (GNUNET_OK == ret) ? 0 : 1;
+}
+
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-21 14:28:45 +0000