|
- /*
- This file is part of GNUnet.
- Copyright (C) 2012, 2013 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 <http://www.gnu.org/licenses/>.
-
- SPDX-License-Identifier: AGPL3.0-or-later
- */
-
- /**
- * @file multicast/multicast_api.c
- * @brief Multicast service; implements multicast groups using CADET connections.
- * @author Christian Grothoff
- * @author Gabor X Toth
- */
-
- #include <gnunet/platform.h>
- #include <gnunet/gnunet_util_lib.h>
- #include "gnunet_multicast_service.h"
- #include "multicast.h"
-
- #define LOG(kind,...) GNUNET_log_from (kind, "multicast-api",__VA_ARGS__)
-
-
- /**
- * Handle for a request to send a message to all multicast group members
- * (from the origin).
- */
- struct GNUNET_MULTICAST_OriginTransmitHandle
- {
- GNUNET_MULTICAST_OriginTransmitNotify notify;
- void *notify_cls;
- struct GNUNET_MULTICAST_Origin *origin;
-
- uint64_t message_id;
- uint64_t group_generation;
- uint64_t fragment_offset;
- };
-
-
- /**
- * Handle for a message to be delivered from a member to the origin.
- */
- struct GNUNET_MULTICAST_MemberTransmitHandle
- {
- GNUNET_MULTICAST_MemberTransmitNotify notify;
- void *notify_cls;
- struct GNUNET_MULTICAST_Member *member;
-
- uint64_t request_id;
- uint64_t fragment_offset;
- };
-
-
- struct GNUNET_MULTICAST_Group
- {
- /**
- * Configuration to use.
- */
- const struct GNUNET_CONFIGURATION_Handle *cfg;
-
- /**
- * Client connection to the service.
- */
- struct GNUNET_MQ_Handle *mq;
-
- /**
- * Message to send on connect.
- */
- struct GNUNET_MQ_Envelope *connect_env;
-
- /**
- * Time to wait until we try to reconnect on failure.
- */
- struct GNUNET_TIME_Relative reconnect_delay;
-
- /**
- * Task for reconnecting when the listener fails.
- */
- struct GNUNET_SCHEDULER_Task *reconnect_task;
-
- GNUNET_MULTICAST_JoinRequestCallback join_req_cb;
- GNUNET_MULTICAST_ReplayFragmentCallback replay_frag_cb;
- GNUNET_MULTICAST_ReplayMessageCallback replay_msg_cb;
- GNUNET_MULTICAST_MessageCallback message_cb;
- void *cb_cls;
-
- /**
- * Function called after disconnected from the service.
- */
- GNUNET_ContinuationCallback disconnect_cb;
-
- /**
- * Closure for @a disconnect_cb.
- */
- void *disconnect_cls;
-
- /**
- * Are we currently transmitting a message?
- */
- uint8_t in_transmit;
-
- /**
- * Number of MULTICAST_FRAGMENT_ACK messages we are still waiting for.
- */
- uint8_t acks_pending;
-
- /**
- * Is this the origin or a member?
- */
- uint8_t is_origin;
-
- /**
- * Is this channel in the process of disconnecting from the service?
- * #GNUNET_YES or #GNUNET_NO
- */
- uint8_t is_disconnecting;
- };
-
-
- /**
- * Handle for the origin of a multicast group.
- */
- struct GNUNET_MULTICAST_Origin
- {
- struct GNUNET_MULTICAST_Group grp;
- struct GNUNET_MULTICAST_OriginTransmitHandle tmit;
-
- GNUNET_MULTICAST_RequestCallback request_cb;
- };
-
-
- /**
- * Handle for a multicast group member.
- */
- struct GNUNET_MULTICAST_Member
- {
- struct GNUNET_MULTICAST_Group grp;
- struct GNUNET_MULTICAST_MemberTransmitHandle tmit;
-
- GNUNET_MULTICAST_JoinDecisionCallback join_dcsn_cb;
-
- /**
- * Replay fragment -> struct GNUNET_MULTICAST_MemberReplayHandle *
- */
- struct GNUNET_CONTAINER_MultiHashMap *replay_reqs;
-
- uint64_t next_fragment_id;
- };
-
-
- /**
- * Handle that identifies a join request.
- *
- * Used to match calls to #GNUNET_MULTICAST_JoinRequestCallback to the
- * corresponding calls to #GNUNET_MULTICAST_join_decision().
- */
- struct GNUNET_MULTICAST_JoinHandle
- {
- struct GNUNET_MULTICAST_Group *group;
-
- /**
- * Public key of the member requesting join.
- */
- struct GNUNET_CRYPTO_EcdsaPublicKey member_pub_key;
-
- /**
- * Peer identity of the member requesting join.
- */
- struct GNUNET_PeerIdentity peer;
- };
-
-
- /**
- * Opaque handle to a replay request from the multicast service.
- */
- struct GNUNET_MULTICAST_ReplayHandle
- {
- struct GNUNET_MULTICAST_Group *grp;
- struct MulticastReplayRequestMessage req;
- };
-
-
- /**
- * Handle for a replay request.
- */
- struct GNUNET_MULTICAST_MemberReplayHandle
- {
- };
-
-
- static void
- origin_to_all (struct GNUNET_MULTICAST_Origin *orig);
-
- static void
- member_to_origin (struct GNUNET_MULTICAST_Member *mem);
-
-
- /**
- * Check join request message.
- */
- static int
- check_group_join_request (void *cls,
- const struct MulticastJoinRequestMessage *jreq)
- {
- uint16_t size = ntohs (jreq->header.size);
-
- if (sizeof (*jreq) == size)
- return GNUNET_OK;
-
- if (sizeof (*jreq) + sizeof (struct GNUNET_MessageHeader) <= size)
- return GNUNET_OK;
-
- return GNUNET_SYSERR;
- }
-
-
- /**
- * Receive join request from service.
- */
- static void
- handle_group_join_request (void *cls,
- const struct MulticastJoinRequestMessage *jreq)
- {
- struct GNUNET_MULTICAST_Group *grp = cls;
- struct GNUNET_MULTICAST_JoinHandle *jh;
- const struct GNUNET_MessageHeader *jmsg = NULL;
-
- if (NULL == grp)
- {
- GNUNET_break (0);
- return;
- }
- if (NULL == grp->join_req_cb)
- return;
-
- if (sizeof (*jreq) + sizeof (*jmsg) <= ntohs (jreq->header.size))
- jmsg = (const struct GNUNET_MessageHeader *) &jreq[1];
-
- jh = GNUNET_malloc (sizeof (*jh));
- jh->group = grp;
- jh->member_pub_key = jreq->member_pub_key;
- jh->peer = jreq->peer;
- grp->join_req_cb (grp->cb_cls, &jreq->member_pub_key, jmsg, jh);
-
- grp->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
- }
-
-
- /**
- * Check multicast message.
- */
- static int
- check_group_message (void *cls,
- const struct GNUNET_MULTICAST_MessageHeader *mmsg)
- {
- return GNUNET_OK;
- }
-
-
- /**
- * Receive multicast message from service.
- */
- static void
- handle_group_message (void *cls,
- const struct GNUNET_MULTICAST_MessageHeader *mmsg)
- {
- struct GNUNET_MULTICAST_Group *grp = cls;
-
- if (GNUNET_YES == grp->is_disconnecting)
- return;
-
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Calling message callback with a message of size %u.\n",
- ntohs (mmsg->header.size));
-
- if (NULL != grp->message_cb)
- grp->message_cb (grp->cb_cls, mmsg);
-
- grp->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
- }
-
-
- /**
- * Receive message/request fragment acknowledgement from service.
- */
- static void
- handle_group_fragment_ack (void *cls,
- const struct GNUNET_MessageHeader *msg)
- {
- struct GNUNET_MULTICAST_Group *grp = cls;
-
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- "%p Got fragment ACK. in_transmit=%u, acks_pending=%u\n",
- grp, grp->in_transmit, grp->acks_pending);
-
- if (0 == grp->acks_pending)
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- "%p Ignoring extraneous fragment ACK.\n", grp);
- return;
- }
- grp->acks_pending--;
-
- if (GNUNET_YES != grp->in_transmit)
- return;
-
- if (GNUNET_YES == grp->is_origin)
- origin_to_all ((struct GNUNET_MULTICAST_Origin *) grp);
- else
- member_to_origin ((struct GNUNET_MULTICAST_Member *) grp);
-
- grp->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
- }
-
-
- /**
- * Check unicast request.
- */
- static int
- check_origin_request (void *cls,
- const struct GNUNET_MULTICAST_RequestHeader *req)
- {
- return GNUNET_OK;
- }
-
-
- /**
- * Origin receives unicast request from a member.
- */
- static void
- handle_origin_request (void *cls,
- const struct GNUNET_MULTICAST_RequestHeader *req)
- {
- struct GNUNET_MULTICAST_Group *grp;
- struct GNUNET_MULTICAST_Origin *orig = cls;
- grp = &orig->grp;
-
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Calling request callback with a request of size %u.\n",
- ntohs (req->header.size));
-
- if (NULL != orig->request_cb)
- orig->request_cb (grp->cb_cls, req);
-
- grp->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
- }
-
-
- /**
- * Receive multicast replay request from service.
- */
- static void
- handle_group_replay_request (void *cls,
- const struct MulticastReplayRequestMessage *rep)
-
- {
- struct GNUNET_MULTICAST_Group *grp = cls;
-
- if (GNUNET_YES == grp->is_disconnecting)
- return;
-
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Got replay request.\n");
-
- if (0 != rep->fragment_id)
- {
- if (NULL != grp->replay_frag_cb)
- {
- struct GNUNET_MULTICAST_ReplayHandle * rh = GNUNET_malloc (sizeof (*rh));
- rh->grp = grp;
- rh->req = *rep;
- grp->replay_frag_cb (grp->cb_cls, &rep->member_pub_key,
- GNUNET_ntohll (rep->fragment_id),
- GNUNET_ntohll (rep->flags), rh);
- }
- }
- else if (0 != rep->message_id)
- {
- if (NULL != grp->replay_msg_cb)
- {
- struct GNUNET_MULTICAST_ReplayHandle * rh = GNUNET_malloc (sizeof (*rh));
- rh->grp = grp;
- rh->req = *rep;
- grp->replay_msg_cb (grp->cb_cls, &rep->member_pub_key,
- GNUNET_ntohll (rep->message_id),
- GNUNET_ntohll (rep->fragment_offset),
- GNUNET_ntohll (rep->flags), rh);
- }
- }
-
- grp->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
- }
-
-
- /**
- * Check replay response.
- */
- static int
- check_member_replay_response (void *cls,
- const struct MulticastReplayResponseMessage *res)
- {
- uint16_t size = ntohs (res->header.size);
-
- if (sizeof (*res) == size)
- return GNUNET_OK;
-
- if (sizeof (*res) + sizeof (struct GNUNET_MULTICAST_MessageHeader) <= size)
- return GNUNET_OK;
-
- return GNUNET_SYSERR;
- }
-
-
- /**
- * Receive replay response from service.
- */
- static void
- handle_member_replay_response (void *cls,
- const struct MulticastReplayResponseMessage *res)
- {
- struct GNUNET_MULTICAST_Group *grp;
- struct GNUNET_MULTICAST_Member *mem = cls;
- grp = &mem->grp;
-
- if (GNUNET_YES == grp->is_disconnecting)
- return;
-
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Got replay response.\n");
-
- // FIXME: return result
- }
-
-
- /**
- * Check join decision.
- */
- static int
- check_member_join_decision (void *cls,
- const struct MulticastJoinDecisionMessageHeader *hdcsn)
- {
- return GNUNET_OK; // checked in handle below
- }
-
-
- /**
- * Member receives join decision.
- */
- static void
- handle_member_join_decision (void *cls,
- const struct MulticastJoinDecisionMessageHeader *hdcsn)
- {
- struct GNUNET_MULTICAST_Group *grp;
- struct GNUNET_MULTICAST_Member *mem = cls;
- grp = &mem->grp;
-
- const struct MulticastJoinDecisionMessage *
- dcsn = (const struct MulticastJoinDecisionMessage *) &hdcsn[1];
-
- uint16_t dcsn_size = ntohs (dcsn->header.size);
- int is_admitted = ntohl (dcsn->is_admitted);
-
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- "%p Member got join decision from multicast: %d\n",
- mem, is_admitted);
-
- const struct GNUNET_MessageHeader *join_resp = NULL;
- uint16_t join_resp_size = 0;
-
- uint16_t relay_count = ntohl (dcsn->relay_count);
- const struct GNUNET_PeerIdentity *relays = NULL;
- uint16_t relay_size = relay_count * sizeof (*relays);
- if (0 < relay_count)
- {
- if (dcsn_size < sizeof (*dcsn) + relay_size)
- {
- GNUNET_break_op (0);
- is_admitted = GNUNET_SYSERR;
- }
- else
- {
- relays = (struct GNUNET_PeerIdentity *) &dcsn[1];
- }
- }
-
- if (sizeof (*dcsn) + relay_size + sizeof (*join_resp) <= dcsn_size)
- {
- join_resp = (const struct GNUNET_MessageHeader *) ((char *) &dcsn[1] + relay_size);
- join_resp_size = ntohs (join_resp->size);
- }
- if (dcsn_size < sizeof (*dcsn) + relay_size + join_resp_size)
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- "Received invalid join decision message from multicast: %u < %u + %u + %u\n",
- dcsn_size , sizeof (*dcsn), relay_size, join_resp_size);
- GNUNET_break_op (0);
- is_admitted = GNUNET_SYSERR;
- }
-
- if (NULL != mem->join_dcsn_cb)
- mem->join_dcsn_cb (grp->cb_cls, is_admitted, &hdcsn->peer,
- relay_count, relays, join_resp);
-
- // FIXME:
- //if (GNUNET_YES != is_admitted)
- // GNUNET_MULTICAST_member_part (mem);
-
- grp->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
- }
-
-
- static void
- group_cleanup (struct GNUNET_MULTICAST_Group *grp)
- {
- if (NULL != grp->connect_env)
- {
- GNUNET_MQ_discard (grp->connect_env);
- grp->connect_env = NULL;
- }
- if (NULL != grp->mq)
- {
- GNUNET_MQ_destroy (grp->mq);
- grp->mq = NULL;
- }
- if (NULL != grp->disconnect_cb)
- {
- grp->disconnect_cb (grp->disconnect_cls);
- grp->disconnect_cb = NULL;
- }
- GNUNET_free (grp);
- }
-
-
- static void
- handle_group_part_ack (void *cls,
- const struct GNUNET_MessageHeader *msg)
- {
- struct GNUNET_MULTICAST_Group *grp = cls;
-
- group_cleanup (grp);
- }
-
-
- /**
- * Function to call with the decision made for a join request.
- *
- * Must be called once and only once in response to an invocation of the
- * #GNUNET_MULTICAST_JoinRequestCallback.
- *
- * @param join
- * Join request handle.
- * @param is_admitted
- * #GNUNET_YES if the join is approved,
- * #GNUNET_NO if it is disapproved,
- * #GNUNET_SYSERR if we cannot answer the request.
- * @param relay_count
- * Number of relays given.
- * @param relays
- * Array of suggested peers that might be useful relays to use
- * when joining the multicast group (essentially a list of peers that
- * are already part of the multicast group and might thus be willing
- * to help with routing). If empty, only this local peer (which must
- * be the multicast origin) is a good candidate for building the
- * multicast tree. Note that it is unnecessary to specify our own
- * peer identity in this array.
- * @param join_resp
- * Message to send in response to the joining peer;
- * can also be used to redirect the peer to a different group at the
- * application layer; this response is to be transmitted to the
- * peer that issued the request even if admission is denied.
- */
- struct GNUNET_MULTICAST_ReplayHandle *
- GNUNET_MULTICAST_join_decision (struct GNUNET_MULTICAST_JoinHandle *join,
- int is_admitted,
- uint16_t relay_count,
- const struct GNUNET_PeerIdentity *relays,
- const struct GNUNET_MessageHeader *join_resp)
- {
- struct GNUNET_MULTICAST_Group *grp = join->group;
- uint16_t join_resp_size = (NULL != join_resp) ? ntohs (join_resp->size) : 0;
- uint16_t relay_size = relay_count * sizeof (*relays);
-
- struct MulticastJoinDecisionMessageHeader *hdcsn;
- struct MulticastJoinDecisionMessage *dcsn;
- struct GNUNET_MQ_Envelope *
- env = GNUNET_MQ_msg_extra (hdcsn, sizeof (*dcsn) + relay_size + join_resp_size,
- GNUNET_MESSAGE_TYPE_MULTICAST_JOIN_DECISION);
- hdcsn->member_pub_key = join->member_pub_key;
- hdcsn->peer = join->peer;
-
- dcsn = (struct MulticastJoinDecisionMessage *) &hdcsn[1];
- dcsn->header.type = htons (GNUNET_MESSAGE_TYPE_MULTICAST_JOIN_DECISION);
- dcsn->header.size = htons (sizeof (*dcsn) + relay_size + join_resp_size);
- dcsn->is_admitted = htonl (is_admitted);
- dcsn->relay_count = htonl (relay_count);
- if (0 < relay_size)
- GNUNET_memcpy (&dcsn[1], relays, relay_size);
- if (0 < join_resp_size)
- GNUNET_memcpy (((char *) &dcsn[1]) + relay_size, join_resp, join_resp_size);
-
- GNUNET_MQ_send (grp->mq, env);
- GNUNET_free (join);
- return NULL;
- }
-
-
- /**
- * Replay a message fragment for the multicast group.
- *
- * @param rh
- * Replay handle identifying which replay operation was requested.
- * @param msg
- * Replayed message fragment, NULL if not found / an error occurred.
- * @param ec
- * Error code. See enum GNUNET_MULTICAST_ReplayErrorCode
- * If not #GNUNET_MULTICAST_REC_OK, the replay handle is invalidated.
- */
- void
- GNUNET_MULTICAST_replay_response (struct GNUNET_MULTICAST_ReplayHandle *rh,
- const struct GNUNET_MessageHeader *msg,
- enum GNUNET_MULTICAST_ReplayErrorCode ec)
- {
- uint8_t msg_size = (NULL != msg) ? ntohs (msg->size) : 0;
- struct MulticastReplayResponseMessage *res;
- struct GNUNET_MQ_Envelope *
- env = GNUNET_MQ_msg_extra (res, msg_size,
- GNUNET_MESSAGE_TYPE_MULTICAST_REPLAY_RESPONSE);
- res->fragment_id = rh->req.fragment_id;
- res->message_id = rh->req.message_id;
- res->fragment_offset = rh->req.fragment_offset;
- res->flags = rh->req.flags;
- res->error_code = htonl (ec);
-
- if (GNUNET_MULTICAST_REC_OK == ec)
- {
- GNUNET_assert (NULL != msg);
- GNUNET_memcpy (&res[1], msg, msg_size);
- }
-
- GNUNET_MQ_send (rh->grp->mq, env);
-
- if (GNUNET_MULTICAST_REC_OK != ec)
- GNUNET_free (rh);
- }
-
-
- /**
- * Indicate the end of the replay session.
- *
- * Invalidates the replay handle.
- *
- * @param rh
- * Replay session to end.
- */
- void
- GNUNET_MULTICAST_replay_response_end (struct GNUNET_MULTICAST_ReplayHandle *rh)
- {
- struct MulticastReplayResponseMessage *end;
- struct GNUNET_MQ_Envelope *
- env = GNUNET_MQ_msg (end, GNUNET_MESSAGE_TYPE_MULTICAST_REPLAY_RESPONSE_END);
-
- end->fragment_id = rh->req.fragment_id;
- end->message_id = rh->req.message_id;
- end->fragment_offset = rh->req.fragment_offset;
- end->flags = rh->req.flags;
-
- GNUNET_MQ_send (rh->grp->mq, env);
- GNUNET_free (rh);
- }
-
-
- /**
- * Replay a message for the multicast group.
- *
- * @param rh
- * Replay handle identifying which replay operation was requested.
- * @param notify
- * Function to call to get the message.
- * @param notify_cls
- * Closure for @a notify.
- */
- void
- GNUNET_MULTICAST_replay_response2 (struct GNUNET_MULTICAST_ReplayHandle *rh,
- GNUNET_MULTICAST_ReplayTransmitNotify notify,
- void *notify_cls)
- {
- }
-
-
- static void
- origin_connect (struct GNUNET_MULTICAST_Origin *orig);
-
-
- static void
- origin_reconnect (void *cls)
- {
- origin_connect (cls);
- }
-
-
- /**
- * Origin client disconnected from service.
- *
- * Reconnect after backoff period.
- */
- static void
- origin_disconnected (void *cls, enum GNUNET_MQ_Error error)
- {
- struct GNUNET_MULTICAST_Origin *orig = cls;
- struct GNUNET_MULTICAST_Group *grp = &orig->grp;
-
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- "Origin client disconnected (%d), re-connecting\n",
- (int) error);
- if (NULL != grp->mq)
- {
- GNUNET_MQ_destroy (grp->mq);
- grp->mq = NULL;
- }
-
- grp->reconnect_task = GNUNET_SCHEDULER_add_delayed (grp->reconnect_delay,
- origin_reconnect,
- orig);
- grp->reconnect_delay = GNUNET_TIME_STD_BACKOFF (grp->reconnect_delay);
- }
-
-
- /**
- * Connect to service as origin.
- */
- static void
- origin_connect (struct GNUNET_MULTICAST_Origin *orig)
- {
- struct GNUNET_MULTICAST_Group *grp = &orig->grp;
-
- struct GNUNET_MQ_MessageHandler handlers[] = {
- GNUNET_MQ_hd_var_size (group_message,
- GNUNET_MESSAGE_TYPE_MULTICAST_MESSAGE,
- struct GNUNET_MULTICAST_MessageHeader,
- grp),
- GNUNET_MQ_hd_var_size (origin_request,
- GNUNET_MESSAGE_TYPE_MULTICAST_REQUEST,
- struct GNUNET_MULTICAST_RequestHeader,
- orig),
- GNUNET_MQ_hd_fixed_size (group_fragment_ack,
- GNUNET_MESSAGE_TYPE_MULTICAST_FRAGMENT_ACK,
- struct GNUNET_MessageHeader,
- grp),
- GNUNET_MQ_hd_var_size (group_join_request,
- GNUNET_MESSAGE_TYPE_MULTICAST_JOIN_REQUEST,
- struct MulticastJoinRequestMessage,
- grp),
- GNUNET_MQ_hd_fixed_size (group_part_ack,
- GNUNET_MESSAGE_TYPE_MULTICAST_PART_ACK,
- struct GNUNET_MessageHeader,
- grp),
- GNUNET_MQ_hd_fixed_size (group_replay_request,
- GNUNET_MESSAGE_TYPE_MULTICAST_REPLAY_REQUEST,
- struct MulticastReplayRequestMessage,
- grp),
- GNUNET_MQ_handler_end ()
- };
-
- grp->mq = GNUNET_CLIENT_connect (grp->cfg, "multicast",
- handlers, origin_disconnected, orig);
- GNUNET_assert (NULL != grp->mq);
- GNUNET_MQ_send_copy (grp->mq, grp->connect_env);
- }
-
-
- /**
- * Start a multicast group.
- *
- * Will advertise the origin in the P2P overlay network under the respective
- * public key so that other peer can find this peer to join it. Peers that
- * issue GNUNET_MULTICAST_member_join() can then transmit a join request to
- * either an existing group member or to the origin. If the joining is
- * approved, the member is cleared for @e replay and will begin to receive
- * messages transmitted to the group. If joining is disapproved, the failed
- * candidate will be given a response. Members in the group can send messages
- * to the origin (one at a time).
- *
- * @param cfg
- * Configuration to use.
- * @param priv_key
- * ECC key that will be used to sign messages for this
- * multicast session; public key is used to identify the multicast group;
- * @param max_fragment_id
- * Maximum fragment ID already sent to the group.
- * 0 for a new group.
- * @param join_request_cb
- * Function called to approve / disapprove joining of a peer.
- * @param replay_frag_cb
- * Function that can be called to replay a message fragment.
- * @param replay_msg_cb
- * Function that can be called to replay a message.
- * @param request_cb
- * Function called with message fragments from group members.
- * @param message_cb
- * Function called with the message fragments sent to the
- * network by GNUNET_MULTICAST_origin_to_all(). These message fragments
- * should be stored for answering replay requests later.
- * @param cls
- * Closure for the various callbacks that follow.
- *
- * @return Handle for the origin, NULL on error.
- */
- struct GNUNET_MULTICAST_Origin *
- GNUNET_MULTICAST_origin_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
- const struct GNUNET_CRYPTO_EddsaPrivateKey *priv_key,
- uint64_t max_fragment_id,
- GNUNET_MULTICAST_JoinRequestCallback join_request_cb,
- GNUNET_MULTICAST_ReplayFragmentCallback replay_frag_cb,
- GNUNET_MULTICAST_ReplayMessageCallback replay_msg_cb,
- GNUNET_MULTICAST_RequestCallback request_cb,
- GNUNET_MULTICAST_MessageCallback message_cb,
- void *cls)
- {
- struct GNUNET_MULTICAST_Origin *orig = GNUNET_malloc (sizeof (*orig));
- struct GNUNET_MULTICAST_Group *grp = &orig->grp;
-
- struct MulticastOriginStartMessage *start;
- grp->connect_env = GNUNET_MQ_msg (start,
- GNUNET_MESSAGE_TYPE_MULTICAST_ORIGIN_START);
- start->max_fragment_id = max_fragment_id;
- start->group_key = *priv_key;
-
- grp->cfg = cfg;
- grp->is_origin = GNUNET_YES;
- grp->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
-
- grp->cb_cls = cls;
- grp->join_req_cb = join_request_cb;
- grp->replay_frag_cb = replay_frag_cb;
- grp->replay_msg_cb = replay_msg_cb;
- grp->message_cb = message_cb;
-
- orig->request_cb = request_cb;
-
- origin_connect (orig);
- return orig;
- }
-
-
- /**
- * Stop a multicast group.
- *
- * @param origin
- * Multicast group to stop.
- */
- void
- GNUNET_MULTICAST_origin_stop (struct GNUNET_MULTICAST_Origin *orig,
- GNUNET_ContinuationCallback stop_cb,
- void *stop_cls)
- {
- struct GNUNET_MULTICAST_Group *grp = &orig->grp;
- struct GNUNET_MQ_Envelope *env;
-
- grp->is_disconnecting = GNUNET_YES;
- grp->disconnect_cb = stop_cb;
- grp->disconnect_cls = stop_cls;
- env = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_MULTICAST_PART_REQUEST);
- GNUNET_MQ_send (grp->mq, env);
- }
-
-
- static void
- origin_to_all (struct GNUNET_MULTICAST_Origin *orig)
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG, "%p origin_to_all()\n", orig);
- struct GNUNET_MULTICAST_Group *grp = &orig->grp;
- struct GNUNET_MULTICAST_OriginTransmitHandle *tmit = &orig->tmit;
- GNUNET_assert (GNUNET_YES == grp->in_transmit);
-
- size_t buf_size = GNUNET_MULTICAST_FRAGMENT_MAX_SIZE;
- struct GNUNET_MULTICAST_MessageHeader *msg;
- struct GNUNET_MQ_Envelope *
- env = GNUNET_MQ_msg_extra (msg, buf_size - sizeof(*msg),
- GNUNET_MESSAGE_TYPE_MULTICAST_MESSAGE);
-
- int ret = tmit->notify (tmit->notify_cls, &buf_size, &msg[1]);
-
- if (! (GNUNET_YES == ret || GNUNET_NO == ret)
- || GNUNET_MULTICAST_FRAGMENT_MAX_SIZE < buf_size)
- {
- LOG (GNUNET_ERROR_TYPE_ERROR,
- "%p OriginTransmitNotify() returned error or invalid message size.\n",
- orig);
- /* FIXME: handle error */
- GNUNET_MQ_discard (env);
- return;
- }
-
- if (GNUNET_NO == ret && 0 == buf_size)
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- "%p OriginTransmitNotify() - transmission paused.\n", orig);
- GNUNET_MQ_discard (env);
- return; /* Transmission paused. */
- }
-
- msg->header.size = htons (sizeof (*msg) + buf_size);
- msg->message_id = GNUNET_htonll (tmit->message_id);
- msg->group_generation = tmit->group_generation;
- msg->fragment_offset = GNUNET_htonll (tmit->fragment_offset);
- tmit->fragment_offset += sizeof (*msg) + buf_size;
-
- grp->acks_pending++;
- GNUNET_MQ_send (grp->mq, env);
-
- if (GNUNET_YES == ret)
- grp->in_transmit = GNUNET_NO;
- }
-
-
- /**
- * Send a message to the multicast group.
- *
- * @param orig
- * Handle to the multicast group.
- * @param message_id
- * Application layer ID for the message. Opaque to multicast.
- * @param group_generation
- * Group generation of the message.
- * Documented in struct GNUNET_MULTICAST_MessageHeader.
- * @param notify
- * Function to call to get the message.
- * @param notify_cls
- * Closure for @a notify.
- *
- * @return Message handle on success,
- * NULL on error (i.e. another request is already pending).
- */
- struct GNUNET_MULTICAST_OriginTransmitHandle *
- GNUNET_MULTICAST_origin_to_all (struct GNUNET_MULTICAST_Origin *orig,
- uint64_t message_id,
- uint64_t group_generation,
- GNUNET_MULTICAST_OriginTransmitNotify notify,
- void *notify_cls)
- {
- struct GNUNET_MULTICAST_Group *grp = &orig->grp;
- if (GNUNET_YES == grp->in_transmit)
- return NULL;
- grp->in_transmit = GNUNET_YES;
-
- struct GNUNET_MULTICAST_OriginTransmitHandle *tmit = &orig->tmit;
- tmit->origin = orig;
- tmit->message_id = message_id;
- tmit->fragment_offset = 0;
- tmit->group_generation = group_generation;
- tmit->notify = notify;
- tmit->notify_cls = notify_cls;
-
- origin_to_all (orig);
- return tmit;
- }
-
-
- /**
- * Resume message transmission to multicast group.
- *
- * @param th
- * Transmission to cancel.
- */
- void
- GNUNET_MULTICAST_origin_to_all_resume (struct GNUNET_MULTICAST_OriginTransmitHandle *th)
- {
- struct GNUNET_MULTICAST_Group *grp = &th->origin->grp;
- if (0 != grp->acks_pending || GNUNET_YES != grp->in_transmit)
- return;
- origin_to_all (th->origin);
- }
-
-
- /**
- * Cancel request for message transmission to multicast group.
- *
- * @param th
- * Transmission to cancel.
- */
- void
- GNUNET_MULTICAST_origin_to_all_cancel (struct GNUNET_MULTICAST_OriginTransmitHandle *th)
- {
- th->origin->grp.in_transmit = GNUNET_NO;
- }
-
-
- static void
- member_connect (struct GNUNET_MULTICAST_Member *mem);
-
-
- static void
- member_reconnect (void *cls)
- {
- member_connect (cls);
- }
-
-
- /**
- * Member client disconnected from service.
- *
- * Reconnect after backoff period.
- */
- static void
- member_disconnected (void *cls, enum GNUNET_MQ_Error error)
- {
- struct GNUNET_MULTICAST_Member *mem = cls;
- struct GNUNET_MULTICAST_Group *grp = &mem->grp;
-
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- "Member client disconnected (%d), re-connecting\n",
- (int) error);
- GNUNET_MQ_destroy (grp->mq);
- grp->mq = NULL;
-
- grp->reconnect_task = GNUNET_SCHEDULER_add_delayed (grp->reconnect_delay,
- member_reconnect,
- mem);
- grp->reconnect_delay = GNUNET_TIME_STD_BACKOFF (grp->reconnect_delay);
- }
-
-
- /**
- * Connect to service as member.
- */
- static void
- member_connect (struct GNUNET_MULTICAST_Member *mem)
- {
- struct GNUNET_MULTICAST_Group *grp = &mem->grp;
-
- struct GNUNET_MQ_MessageHandler handlers[] = {
- GNUNET_MQ_hd_var_size (group_message,
- GNUNET_MESSAGE_TYPE_MULTICAST_MESSAGE,
- struct GNUNET_MULTICAST_MessageHeader,
- grp),
- GNUNET_MQ_hd_fixed_size (group_fragment_ack,
- GNUNET_MESSAGE_TYPE_MULTICAST_FRAGMENT_ACK,
- struct GNUNET_MessageHeader,
- grp),
- GNUNET_MQ_hd_var_size (group_join_request,
- GNUNET_MESSAGE_TYPE_MULTICAST_JOIN_REQUEST,
- struct MulticastJoinRequestMessage,
- grp),
- GNUNET_MQ_hd_var_size (member_join_decision,
- GNUNET_MESSAGE_TYPE_MULTICAST_JOIN_DECISION,
- struct MulticastJoinDecisionMessageHeader,
- mem),
- GNUNET_MQ_hd_fixed_size (group_part_ack,
- GNUNET_MESSAGE_TYPE_MULTICAST_PART_ACK,
- struct GNUNET_MessageHeader,
- grp),
- GNUNET_MQ_hd_fixed_size (group_replay_request,
- GNUNET_MESSAGE_TYPE_MULTICAST_REPLAY_REQUEST,
- struct MulticastReplayRequestMessage,
- grp),
- GNUNET_MQ_hd_var_size (member_replay_response,
- GNUNET_MESSAGE_TYPE_MULTICAST_REPLAY_RESPONSE,
- struct MulticastReplayResponseMessage,
- mem),
- GNUNET_MQ_handler_end ()
- };
-
- grp->mq = GNUNET_CLIENT_connect (grp->cfg, "multicast",
- handlers, member_disconnected, mem);
- GNUNET_assert (NULL != grp->mq);
- GNUNET_MQ_send_copy (grp->mq, grp->connect_env);
- }
-
-
- /**
- * Join a multicast group.
- *
- * The entity joining is always the local peer. Further information about the
- * candidate can be provided in the @a join_request message. If the join fails, the
- * @a message_cb is invoked with a (failure) response and then with NULL. If
- * the join succeeds, outstanding (state) messages and ongoing multicast
- * messages will be given to the @a message_cb until the member decides to part
- * the group. The @a replay_cb function may be called at any time by the
- * multicast service to support relaying messages to other members of the group.
- *
- * @param cfg
- * Configuration to use.
- * @param group_key
- * ECC public key that identifies the group to join.
- * @param member_key
- * ECC key that identifies the member
- * and used to sign requests sent to the origin.
- * @param origin
- * Peer ID of the origin to send unicast requsets to. If NULL,
- * unicast requests are sent back via multiple hops on the reverse path
- * of multicast messages.
- * @param relay_count
- * Number of peers in the @a relays array.
- * @param relays
- * Peer identities of members of the group, which serve as relays
- * and can be used to join the group at. and send the @a join_request to.
- * If empty, the @a join_request is sent directly to the @a origin.
- * @param join_msg
- * Application-dependent join message to be passed to the peer @a origin.
- * @param join_request_cb
- * Function called to approve / disapprove joining of a peer.
- * @param join_decision_cb
- * Function called to inform about the join decision.
- * @param replay_frag_cb
- * Function that can be called to replay message fragments
- * this peer already knows from this group. NULL if this
- * client is unable to support replay.
- * @param replay_msg_cb
- * Function that can be called to replay message fragments
- * this peer already knows from this group. NULL if this
- * client is unable to support replay.
- * @param message_cb
- * Function to be called for all message fragments we
- * receive from the group, excluding those our @a replay_cb
- * already has.
- * @param cls
- * Closure for callbacks.
- *
- * @return Handle for the member, NULL on error.
- */
- struct GNUNET_MULTICAST_Member *
- GNUNET_MULTICAST_member_join (const struct GNUNET_CONFIGURATION_Handle *cfg,
- const struct GNUNET_CRYPTO_EddsaPublicKey *group_pub_key,
- const struct GNUNET_CRYPTO_EcdsaPrivateKey *member_key,
- const struct GNUNET_PeerIdentity *origin,
- uint16_t relay_count,
- const struct GNUNET_PeerIdentity *relays,
- const struct GNUNET_MessageHeader *join_msg,
- GNUNET_MULTICAST_JoinRequestCallback join_request_cb,
- GNUNET_MULTICAST_JoinDecisionCallback join_decision_cb,
- GNUNET_MULTICAST_ReplayFragmentCallback replay_frag_cb,
- GNUNET_MULTICAST_ReplayMessageCallback replay_msg_cb,
- GNUNET_MULTICAST_MessageCallback message_cb,
- void *cls)
- {
- struct GNUNET_MULTICAST_Member *mem = GNUNET_malloc (sizeof (*mem));
- struct GNUNET_MULTICAST_Group *grp = &mem->grp;
-
- uint16_t relay_size = relay_count * sizeof (*relays);
- uint16_t join_msg_size = (NULL != join_msg) ? ntohs (join_msg->size) : 0;
- struct MulticastMemberJoinMessage *join;
- grp->connect_env = GNUNET_MQ_msg_extra (join, relay_size + join_msg_size,
- GNUNET_MESSAGE_TYPE_MULTICAST_MEMBER_JOIN);
- join->group_pub_key = *group_pub_key;
- join->member_key = *member_key;
- join->origin = *origin;
- join->relay_count = ntohl (relay_count);
- if (0 < relay_size)
- GNUNET_memcpy (&join[1], relays, relay_size);
- if (0 < join_msg_size)
- GNUNET_memcpy (((char *) &join[1]) + relay_size, join_msg, join_msg_size);
-
- grp->cfg = cfg;
- grp->is_origin = GNUNET_NO;
- grp->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
-
- mem->join_dcsn_cb = join_decision_cb;
- grp->join_req_cb = join_request_cb;
- grp->replay_frag_cb = replay_frag_cb;
- grp->replay_msg_cb = replay_msg_cb;
- grp->message_cb = message_cb;
- grp->cb_cls = cls;
-
- member_connect (mem);
- return mem;
- }
-
-
- /**
- * Part a multicast group.
- *
- * Disconnects from all group members and invalidates the @a member handle.
- *
- * An application-dependent part message can be transmitted beforehand using
- * #GNUNET_MULTICAST_member_to_origin())
- *
- * @param member
- * Membership handle.
- */
- void
- GNUNET_MULTICAST_member_part (struct GNUNET_MULTICAST_Member *mem,
- GNUNET_ContinuationCallback part_cb,
- void *part_cls)
- {
- struct GNUNET_MULTICAST_Group *grp = &mem->grp;
- struct GNUNET_MQ_Envelope *env;
-
- mem->join_dcsn_cb = NULL;
- grp->join_req_cb = NULL;
- grp->message_cb = NULL;
- grp->replay_msg_cb = NULL;
- grp->replay_frag_cb = NULL;
- grp->is_disconnecting = GNUNET_YES;
- grp->disconnect_cb = part_cb;
- grp->disconnect_cls = part_cls;
- env = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_MULTICAST_PART_REQUEST);
- GNUNET_MQ_send (grp->mq, env);
- }
-
-
- void
- member_replay_request (struct GNUNET_MULTICAST_Member *mem,
- uint64_t fragment_id,
- uint64_t message_id,
- uint64_t fragment_offset,
- uint64_t flags)
- {
- struct MulticastReplayRequestMessage *rep;
- struct GNUNET_MQ_Envelope *
- env = GNUNET_MQ_msg (rep, GNUNET_MESSAGE_TYPE_MULTICAST_REPLAY_REQUEST);
-
- rep->fragment_id = GNUNET_htonll (fragment_id);
- rep->message_id = GNUNET_htonll (message_id);
- rep->fragment_offset = GNUNET_htonll (fragment_offset);
- rep->flags = GNUNET_htonll (flags);
-
- GNUNET_MQ_send (mem->grp.mq, env);
- }
-
-
- /**
- * Request a fragment to be replayed by fragment ID.
- *
- * Useful if messages below the @e max_known_fragment_id given when joining are
- * needed and not known to the client.
- *
- * @param member
- * Membership handle.
- * @param fragment_id
- * ID of a message fragment that this client would like to see replayed.
- * @param flags
- * Additional flags for the replay request.
- * It is used and defined by GNUNET_MULTICAST_ReplayFragmentCallback
- *
- * @return Replay request handle.
- */
- struct GNUNET_MULTICAST_MemberReplayHandle *
- GNUNET_MULTICAST_member_replay_fragment (struct GNUNET_MULTICAST_Member *mem,
- uint64_t fragment_id,
- uint64_t flags)
- {
- member_replay_request (mem, fragment_id, 0, 0, flags);
- // FIXME: return something useful
- return NULL;
- }
-
-
- /**
- * Request a message fragment to be replayed.
- *
- * Useful if messages below the @e max_known_fragment_id given when joining are
- * needed and not known to the client.
- *
- * @param member
- * Membership handle.
- * @param message_id
- * ID of the message this client would like to see replayed.
- * @param fragment_offset
- * Offset of the fragment within the message to replay.
- * @param flags
- * Additional flags for the replay request.
- * It is used & defined by GNUNET_MULTICAST_ReplayMessageCallback
- *
- * @return Replay request handle, NULL on error.
- */
- struct GNUNET_MULTICAST_MemberReplayHandle *
- GNUNET_MULTICAST_member_replay_message (struct GNUNET_MULTICAST_Member *mem,
- uint64_t message_id,
- uint64_t fragment_offset,
- uint64_t flags)
- {
- member_replay_request (mem, 0, message_id, fragment_offset, flags);
- // FIXME: return something useful
- return NULL;
- }
-
-
- static void
- member_to_origin (struct GNUNET_MULTICAST_Member *mem)
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG, "member_to_origin()\n");
- struct GNUNET_MULTICAST_Group *grp = &mem->grp;
- struct GNUNET_MULTICAST_MemberTransmitHandle *tmit = &mem->tmit;
- GNUNET_assert (GNUNET_YES == grp->in_transmit);
-
- size_t buf_size = GNUNET_MULTICAST_FRAGMENT_MAX_SIZE;
- struct GNUNET_MULTICAST_RequestHeader *req;
- struct GNUNET_MQ_Envelope *
- env = GNUNET_MQ_msg_extra (req, buf_size - sizeof(*req),
- GNUNET_MESSAGE_TYPE_MULTICAST_REQUEST);
-
- int ret = tmit->notify (tmit->notify_cls, &buf_size, &req[1]);
-
- if (! (GNUNET_YES == ret || GNUNET_NO == ret)
- || GNUNET_MULTICAST_FRAGMENT_MAX_SIZE < buf_size)
- {
- LOG (GNUNET_ERROR_TYPE_ERROR,
- "MemberTransmitNotify() returned error or invalid message size. "
- "ret=%d, buf_size=%u\n", ret, buf_size);
- /* FIXME: handle error */
- GNUNET_MQ_discard (env);
- return;
- }
-
- if (GNUNET_NO == ret && 0 == buf_size)
- {
- /* Transmission paused. */
- GNUNET_MQ_discard (env);
- return;
- }
-
- req->header.size = htons (sizeof (*req) + buf_size);
- req->request_id = GNUNET_htonll (tmit->request_id);
- req->fragment_offset = GNUNET_ntohll (tmit->fragment_offset);
- tmit->fragment_offset += sizeof (*req) + buf_size;
-
- GNUNET_MQ_send (grp->mq, env);
-
- if (GNUNET_YES == ret)
- grp->in_transmit = GNUNET_NO;
- }
-
-
- /**
- * Send a message to the origin of the multicast group.
- *
- * @param mem
- * Membership handle.
- * @param request_id
- * Application layer ID for the request. Opaque to multicast.
- * @param notify
- * Callback to call to get the message.
- * @param notify_cls
- * Closure for @a notify.
- *
- * @return Handle to cancel request, NULL on error (i.e. request already pending).
- */
- struct GNUNET_MULTICAST_MemberTransmitHandle *
- GNUNET_MULTICAST_member_to_origin (struct GNUNET_MULTICAST_Member *mem,
- uint64_t request_id,
- GNUNET_MULTICAST_MemberTransmitNotify notify,
- void *notify_cls)
- {
- if (GNUNET_YES == mem->grp.in_transmit)
- return NULL;
- mem->grp.in_transmit = GNUNET_YES;
-
- struct GNUNET_MULTICAST_MemberTransmitHandle *tmit = &mem->tmit;
- tmit->member = mem;
- tmit->request_id = request_id;
- tmit->fragment_offset = 0;
- tmit->notify = notify;
- tmit->notify_cls = notify_cls;
-
- member_to_origin (mem);
- return tmit;
- }
-
-
- /**
- * Resume message transmission to origin.
- *
- * @param th
- * Transmission to cancel.
- */
- void
- GNUNET_MULTICAST_member_to_origin_resume (struct GNUNET_MULTICAST_MemberTransmitHandle *th)
- {
- struct GNUNET_MULTICAST_Group *grp = &th->member->grp;
- if (0 != grp->acks_pending || GNUNET_YES != grp->in_transmit)
- return;
- member_to_origin (th->member);
- }
-
-
- /**
- * Cancel request for message transmission to origin.
- *
- * @param th
- * Transmission to cancel.
- */
- void
- GNUNET_MULTICAST_member_to_origin_cancel (struct GNUNET_MULTICAST_MemberTransmitHandle *th)
- {
- th->member->grp.in_transmit = GNUNET_NO;
- }
-
-
- /* end of multicast_api.c */
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