/* This file is part of GNUnet. Copyright (C) 2009-2013, 2016 GNUnet e.V. 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 3, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ /** * @file transport/transport_api.c * @brief library to access the low-level P2P IO service * @author Christian Grothoff * * TODO: * - test test test */ #include "platform.h" #include "gnunet_util_lib.h" #include "gnunet_constants.h" #include "gnunet_arm_service.h" #include "gnunet_hello_lib.h" #include "gnunet_protocols.h" #include "gnunet_transport_service.h" #include "transport.h" #define LOG(kind,...) GNUNET_log_from (kind, "transport-api",__VA_ARGS__) /** * If we could not send any payload to a peer for this amount of * time, we print a warning. */ #define UNREADY_WARN_TIME GNUNET_TIME_UNIT_MINUTES /** * How large to start with for the hashmap of neighbours. */ #define STARTING_NEIGHBOURS_SIZE 16 /** * Handle for a message that should be transmitted to the service. * Used for both control messages and normal messages. */ struct GNUNET_TRANSPORT_TransmitHandle { /** * We keep all requests in a DLL. */ struct GNUNET_TRANSPORT_TransmitHandle *next; /** * We keep all requests in a DLL. */ struct GNUNET_TRANSPORT_TransmitHandle *prev; /** * Neighbour for this handle, NULL for control messages. */ struct Neighbour *neighbour; /** * Function to call when @e notify_size bytes are available * for transmission. */ GNUNET_TRANSPORT_TransmitReadyNotify notify; /** * Closure for @e notify. */ void *notify_cls; /** * Time at which this request was originally scheduled. */ struct GNUNET_TIME_Absolute request_start; /** * Timeout for this request, 0 for control messages. */ struct GNUNET_TIME_Absolute timeout; /** * Task to trigger request timeout if the request is stalled due to * congestion. */ struct GNUNET_SCHEDULER_Task *timeout_task; /** * How many bytes is our notify callback waiting for? */ size_t notify_size; }; /** * Entry in hash table of all of our current (connected) neighbours. */ struct Neighbour { /** * Overall transport handle. */ struct GNUNET_TRANSPORT_Handle *h; /** * Active transmit handle or NULL. */ struct GNUNET_TRANSPORT_TransmitHandle *th; /** * Identity of this neighbour. */ struct GNUNET_PeerIdentity id; /** * Outbound bandwidh tracker. */ struct GNUNET_BANDWIDTH_Tracker out_tracker; /** * Entry in our readyness heap (which is sorted by @e next_ready * value). NULL if there is no pending transmission request for * this neighbour or if we're waiting for @e is_ready to become * true AFTER the @e out_tracker suggested that this peer's quota * has been satisfied (so once @e is_ready goes to #GNUNET_YES, * we should immediately go back into the heap). */ struct GNUNET_CONTAINER_HeapNode *hn; /** * Last time when this peer received payload from us. */ struct GNUNET_TIME_Absolute last_payload; /** * Task to trigger warnings if we do not get SEND_OK after a while. */ struct GNUNET_SCHEDULER_Task *unready_warn_task; /** * Is this peer currently ready to receive a message? */ int is_ready; /** * Sending consumed more bytes on wire than payload was announced * This overhead is added to the delay of next sending operation */ size_t traffic_overhead; }; /** * Handle for the transport service (includes all of the * state for the transport service). */ struct GNUNET_TRANSPORT_Handle { /** * Closure for the callbacks. */ void *cls; /** * Function to call for received data. */ GNUNET_TRANSPORT_ReceiveCallback rec; /** * function to call on connect events */ GNUNET_TRANSPORT_NotifyConnect nc_cb; /** * function to call on disconnect events */ GNUNET_TRANSPORT_NotifyDisconnect nd_cb; /** * function to call on excess bandwidth events */ GNUNET_TRANSPORT_NotifyExcessBandwidth neb_cb; /** * The current HELLO message for this peer. Updated * whenever transports change their addresses. */ struct GNUNET_MessageHeader *my_hello; /** * My client connection to the transport service. */ struct GNUNET_MQ_Handle *mq; /** * My configuration. */ const struct GNUNET_CONFIGURATION_Handle *cfg; /** * Hash map of the current connected neighbours of this peer. * Maps peer identities to `struct Neighbour` entries. */ struct GNUNET_CONTAINER_MultiPeerMap *neighbours; /** * Heap sorting peers with pending messages by the timestamps that * specify when we could next send a message to the respective peer. * Excludes control messages (which can always go out immediately). * Maps time stamps to `struct Neighbour` entries. */ struct GNUNET_CONTAINER_Heap *ready_heap; /** * Peer identity as assumed by this process, or all zeros. */ struct GNUNET_PeerIdentity self; /** * ID of the task trying to reconnect to the service. */ struct GNUNET_SCHEDULER_Task *reconnect_task; /** * ID of the task trying to trigger transmission for a peer while * maintaining bandwidth quotas. In use if there are no control * messages and the smallest entry in the @e ready_heap has a time * stamp in the future. */ struct GNUNET_SCHEDULER_Task *quota_task; /** * Delay until we try to reconnect. */ struct GNUNET_TIME_Relative reconnect_delay; /** * Should we check that @e self matches what the service thinks? * (if #GNUNET_NO, then @e self is all zeros!). */ int check_self; /** * Reconnect in progress */ int reconnecting; }; /** * Schedule the task to send one message, either from the control * list or the peer message queues to the service. * * @param h transport service to schedule a transmission for */ static void schedule_transmission (struct GNUNET_TRANSPORT_Handle *h); /** * Function that will schedule the job that will try * to connect us again to the client. * * @param h transport service to reconnect */ static void disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h); /** * A neighbour has not gotten a SEND_OK in a while. Print a warning. * * @param cls the `struct Neighbour` */ static void do_warn_unready (void *cls) { struct Neighbour *n = cls; struct GNUNET_TIME_Relative delay; delay = GNUNET_TIME_absolute_get_duration (n->last_payload); GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Lacking SEND_OK, no payload could be send to %s for %s\n", GNUNET_i2s (&n->id), GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES)); n->unready_warn_task = GNUNET_SCHEDULER_add_delayed (UNREADY_WARN_TIME, &do_warn_unready, n); } /** * Get the neighbour list entry for the given peer * * @param h our context * @param peer peer to look up * @return NULL if no such peer entry exists */ static struct Neighbour * neighbour_find (struct GNUNET_TRANSPORT_Handle *h, const struct GNUNET_PeerIdentity *peer) { return GNUNET_CONTAINER_multipeermap_get (h->neighbours, peer); } /** * The outbound quota has changed in a way that may require * us to reset the timeout. Update the timeout. * * @param cls the `struct Neighbour` for which the timeout changed */ static void outbound_bw_tracker_update (void *cls) { struct Neighbour *n = cls; struct GNUNET_TIME_Relative delay; if (NULL == n->hn) return; delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, n->th->notify_size + n->traffic_overhead); LOG (GNUNET_ERROR_TYPE_DEBUG, "New outbound delay %s us\n", GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_NO)); GNUNET_CONTAINER_heap_update_cost (n->h->ready_heap, n->hn, delay.rel_value_us); schedule_transmission (n->h); } /** * Function called by the bandwidth tracker if we have excess * bandwidth. * * @param cls the `struct Neighbour` that has excess bandwidth */ static void notify_excess_cb (void *cls) { struct Neighbour *n = cls; struct GNUNET_TRANSPORT_Handle *h = n->h; if (NULL != h->neb_cb) h->neb_cb (h->cls, &n->id); } /** * Add neighbour to our list * * @return NULL if this API is currently disconnecting from the service */ static struct Neighbour * neighbour_add (struct GNUNET_TRANSPORT_Handle *h, const struct GNUNET_PeerIdentity *pid) { struct Neighbour *n; LOG (GNUNET_ERROR_TYPE_DEBUG, "Creating entry for neighbour `%s'.\n", GNUNET_i2s (pid)); n = GNUNET_new (struct Neighbour); n->id = *pid; n->h = h; n->is_ready = GNUNET_YES; n->traffic_overhead = 0; GNUNET_BANDWIDTH_tracker_init2 (&n->out_tracker, &outbound_bw_tracker_update, n, GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT, MAX_BANDWIDTH_CARRY_S, ¬ify_excess_cb, n); GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_multipeermap_put (h->neighbours, &n->id, n, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)); return n; } /** * Iterator over hash map entries, for deleting state of a neighbour. * * @param cls the `struct GNUNET_TRANSPORT_Handle *` * @param key peer identity * @param value value in the hash map, the neighbour entry to delete * @return #GNUNET_YES if we should continue to * iterate, * #GNUNET_NO if not. */ static int neighbour_delete (void *cls, const struct GNUNET_PeerIdentity *key, void *value) { struct GNUNET_TRANSPORT_Handle *handle = cls; struct Neighbour *n = value; LOG (GNUNET_ERROR_TYPE_DEBUG, "Dropping entry for neighbour `%s'.\n", GNUNET_i2s (key)); GNUNET_BANDWIDTH_tracker_notification_stop (&n->out_tracker); if (NULL != handle->nd_cb) handle->nd_cb (handle->cls, &n->id); if (NULL != n->unready_warn_task) { GNUNET_SCHEDULER_cancel (n->unready_warn_task); n->unready_warn_task = NULL; } GNUNET_assert (NULL == n->th); GNUNET_assert (NULL == n->hn); GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multipeermap_remove (handle->neighbours, key, n)); GNUNET_free (n); return GNUNET_YES; } /** * Generic error handler, called with the appropriate * error code and the same closure specified at the creation of * the message queue. * Not every message queue implementation supports an error handler. * * @param cls closure with the `struct GNUNET_TRANSPORT_Handle *` * @param error error code */ static void mq_error_handler (void *cls, enum GNUNET_MQ_Error error) { struct GNUNET_TRANSPORT_Handle *h = cls; LOG (GNUNET_ERROR_TYPE_DEBUG, "Error receiving from transport service, disconnecting temporarily.\n"); h->reconnecting = GNUNET_YES; disconnect_and_schedule_reconnect (h); } /** * Function we use for checking incoming HELLO messages. * * @param cls closure, a `struct GNUNET_TRANSPORT_Handle *` * @param msg message received * @return #GNUNET_OK if message is well-formed */ static int check_hello (void *cls, const struct GNUNET_MessageHeader *msg) { struct GNUNET_PeerIdentity me; if (GNUNET_OK != GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg, &me)) { GNUNET_break (0); return GNUNET_SYSERR; } LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving (my own) HELLO message (%u bytes), I am `%s'.\n", (unsigned int) ntohs (msg->size), GNUNET_i2s (&me)); return GNUNET_OK; } /** * Function we use for handling incoming HELLO messages. * * @param cls closure, a `struct GNUNET_TRANSPORT_Handle *` * @param msg message received */ static void handle_hello (void *cls, const struct GNUNET_MessageHeader *msg) { struct GNUNET_TRANSPORT_Handle *h = cls; GNUNET_free_non_null (h->my_hello); h->my_hello = GNUNET_copy_message (msg); } /** * Function we use for handling incoming connect messages. * * @param cls closure, a `struct GNUNET_TRANSPORT_Handle *` * @param cim message received */ static void handle_connect (void *cls, const struct ConnectInfoMessage *cim) { struct GNUNET_TRANSPORT_Handle *h = cls; struct Neighbour *n; LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving CONNECT message for `%s'.\n", GNUNET_i2s (&cim->id)); n = neighbour_find (h, &cim->id); if (NULL != n) { GNUNET_break (0); h->reconnecting = GNUNET_YES; disconnect_and_schedule_reconnect (h); return; } n = neighbour_add (h, &cim->id); LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving CONNECT message for `%s' with quota %u\n", GNUNET_i2s (&cim->id), ntohl (cim->quota_out.value__)); GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, cim->quota_out); if (NULL != h->nc_cb) h->nc_cb (h->cls, &n->id); } /** * Function we use for handling incoming disconnect messages. * * @param cls closure, a `struct GNUNET_TRANSPORT_Handle *` * @param dim message received */ static void handle_disconnect (void *cls, const struct DisconnectInfoMessage *dim) { struct GNUNET_TRANSPORT_Handle *h = cls; struct Neighbour *n; GNUNET_break (ntohl (dim->reserved) == 0); LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving DISCONNECT message for `%s'.\n", GNUNET_i2s (&dim->peer)); n = neighbour_find (h, &dim->peer); if (NULL == n) { GNUNET_break (0); h->reconnecting = GNUNET_YES; disconnect_and_schedule_reconnect (h); return; } neighbour_delete (h, &dim->peer, n); } /** * Function we use for handling incoming send-ok messages. * * @param cls closure, a `struct GNUNET_TRANSPORT_Handle *` * @param okm message received */ static void handle_send_ok (void *cls, const struct SendOkMessage *okm) { struct GNUNET_TRANSPORT_Handle *h = cls; struct Neighbour *n; uint32_t bytes_msg; uint32_t bytes_physical; bytes_msg = ntohl (okm->bytes_msg); bytes_physical = ntohl (okm->bytes_physical); LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving SEND_OK message, transmission to %s %s.\n", GNUNET_i2s (&okm->peer), ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed"); n = neighbour_find (h, &okm->peer); if (NULL == n) { /* We should never get a 'SEND_OK' for a peer that we are not connected to */ GNUNET_break (0); h->reconnecting = GNUNET_YES; disconnect_and_schedule_reconnect (h); return; } if (bytes_physical > bytes_msg) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Overhead for %u byte message was %u\n", bytes_msg, bytes_physical - bytes_msg); n->traffic_overhead += bytes_physical - bytes_msg; } GNUNET_break (GNUNET_NO == n->is_ready); n->is_ready = GNUNET_YES; if (NULL != n->unready_warn_task) { GNUNET_SCHEDULER_cancel (n->unready_warn_task); n->unready_warn_task = NULL; } if ((NULL != n->th) && (NULL == n->hn)) { GNUNET_assert (NULL != n->th->timeout_task); GNUNET_SCHEDULER_cancel (n->th->timeout_task); n->th->timeout_task = NULL; /* we've been waiting for this (congestion, not quota, * caused delayed transmission) */ n->hn = GNUNET_CONTAINER_heap_insert (h->ready_heap, n, 0); } schedule_transmission (h); } /** * Function we use for checking incoming "inbound" messages. * * @param cls closure, a `struct GNUNET_TRANSPORT_Handle *` * @param im message received */ static int check_recv (void *cls, const struct InboundMessage *im) { const struct GNUNET_MessageHeader *imm; uint16_t size; size = ntohs (im->header.size); if (size < sizeof (struct InboundMessage) + sizeof (struct GNUNET_MessageHeader)) { GNUNET_break (0); return GNUNET_SYSERR; } imm = (const struct GNUNET_MessageHeader *) &im[1]; if (ntohs (imm->size) + sizeof (struct InboundMessage) != size) { GNUNET_break (0); return GNUNET_SYSERR; } return GNUNET_OK; } /** * Function we use for handling incoming messages. * * @param cls closure, a `struct GNUNET_TRANSPORT_Handle *` * @param im message received */ static void handle_recv (void *cls, const struct InboundMessage *im) { struct GNUNET_TRANSPORT_Handle *h = cls; const struct GNUNET_MessageHeader *imm = (const struct GNUNET_MessageHeader *) &im[1]; struct Neighbour *n; LOG (GNUNET_ERROR_TYPE_DEBUG, "Received message of type %u with %u bytes from `%s'.\n", (unsigned int) ntohs (imm->type), (unsigned int) ntohs (imm->size), GNUNET_i2s (&im->peer)); n = neighbour_find (h, &im->peer); if (NULL == n) { GNUNET_break (0); h->reconnecting = GNUNET_YES; disconnect_and_schedule_reconnect (h); return; } if (NULL != h->rec) h->rec (h->cls, &im->peer, imm); } /** * Function we use for handling incoming set quota messages. * * @param cls closure, a `struct GNUNET_TRANSPORT_Handle *` * @param msg message received */ static void handle_set_quota (void *cls, const struct QuotaSetMessage *qm) { struct GNUNET_TRANSPORT_Handle *h = cls; struct Neighbour *n; n = neighbour_find (h, &qm->peer); if (NULL == n) { GNUNET_break (0); h->reconnecting = GNUNET_YES; disconnect_and_schedule_reconnect (h); return; } LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving SET_QUOTA message for `%s' with quota %u\n", GNUNET_i2s (&qm->peer), ntohl (qm->quota.value__)); GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, qm->quota); } /** * A transmission request could not be satisfied because of * network congestion. Notify the initiator and clean up. * * @param cls the `struct GNUNET_TRANSPORT_TransmitHandle` */ static void timeout_request_due_to_congestion (void *cls) { struct GNUNET_TRANSPORT_TransmitHandle *th = cls; struct Neighbour *n = th->neighbour; struct GNUNET_TIME_Relative delay; n->th->timeout_task = NULL; delay = GNUNET_TIME_absolute_get_duration (th->request_start); LOG (GNUNET_ERROR_TYPE_WARNING, "Discarding %u bytes of payload message after %s delay due to congestion\n", th->notify_size, GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES)); GNUNET_assert (th == n->th); GNUNET_assert (NULL == n->hn); n->th = NULL; th->notify (th->notify_cls, 0, NULL); GNUNET_free (th); } /** * Transmit ready message(s) to service. * * @param h handle to transport */ static void transmit_ready (struct GNUNET_TRANSPORT_Handle *h) { struct GNUNET_TRANSPORT_TransmitHandle *th; struct GNUNET_TIME_Relative delay; struct Neighbour *n; struct OutboundMessage *obm; struct GNUNET_MQ_Envelope *env; size_t mret; GNUNET_assert (NULL != h->mq); while (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) { th = n->th; if (GNUNET_YES != n->is_ready) { /* peer not ready, wait for notification! */ GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap)); n->hn = NULL; GNUNET_assert (NULL == n->th->timeout_task); th->timeout_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining (th->timeout), &timeout_request_due_to_congestion, th); continue; } if (GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, th->notify_size).rel_value_us > 0) break; /* too early */ GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap)); n->hn = NULL; n->th = NULL; env = GNUNET_MQ_msg_extra (obm, th->notify_size, GNUNET_MESSAGE_TYPE_TRANSPORT_SEND); mret = th->notify (th->notify_cls, th->notify_size, &obm[1]); if (0 == mret) { GNUNET_free (th); GNUNET_MQ_discard (env); continue; } obm->header.size = htons (mret + sizeof (*obm)); if (NULL != n->unready_warn_task) n->unready_warn_task = GNUNET_SCHEDULER_add_delayed (UNREADY_WARN_TIME, &do_warn_unready, n); n->last_payload = GNUNET_TIME_absolute_get (); n->is_ready = GNUNET_NO; obm->reserved = htonl (0); obm->timeout = GNUNET_TIME_relative_hton (GNUNET_TIME_absolute_get_remaining (th->timeout)); obm->peer = n->id; GNUNET_MQ_send (h->mq, env); GNUNET_BANDWIDTH_tracker_consume (&n->out_tracker, mret); delay = GNUNET_TIME_absolute_get_duration (th->request_start); if (delay.rel_value_us > GNUNET_CONSTANTS_LATENCY_WARN.rel_value_us) LOG (GNUNET_ERROR_TYPE_WARNING, "Added %u bytes of payload message for %s after %s delay at %u b/s\n", mret, GNUNET_i2s (&n->id), GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES), (unsigned int) n->out_tracker.available_bytes_per_s__); else LOG (GNUNET_ERROR_TYPE_DEBUG, "Added %u bytes of payload message for %s after %s delay at %u b/s\n", mret, GNUNET_i2s (&n->id), GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES), (unsigned int) n->out_tracker.available_bytes_per_s__); GNUNET_free (th); } /* if there are more pending messages, try to schedule those */ schedule_transmission (h); } /** * Schedule the task to send one message, either from the control * list or the peer message queues to the service. * * @param cls transport service to schedule a transmission for */ static void schedule_transmission_task (void *cls) { struct GNUNET_TRANSPORT_Handle *h = cls; struct GNUNET_TRANSPORT_TransmitHandle *th; struct Neighbour *n; h->quota_task = NULL; GNUNET_assert (NULL != h->mq); /* destroy all requests that have timed out */ while ( (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) && (0 == GNUNET_TIME_absolute_get_remaining (n->th->timeout).rel_value_us) ) { /* notify client that the request could not be satisfied within * the given time constraints */ th = n->th; n->th = NULL; GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap)); n->hn = NULL; LOG (GNUNET_ERROR_TYPE_DEBUG, "Signalling timeout for transmission to peer %s due to congestion\n", GNUNET_i2s (&n->id)); GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL)); GNUNET_free (th); } n = GNUNET_CONTAINER_heap_peek (h->ready_heap); if (NULL == n) return; /* no pending messages */ LOG (GNUNET_ERROR_TYPE_DEBUG, "Calling notify_transmit_ready\n"); transmit_ready (h); } /** * Schedule the task to send one message, either from the control * list or the peer message queues to the service. * * @param h transport service to schedule a transmission for */ static void schedule_transmission (struct GNUNET_TRANSPORT_Handle *h) { struct GNUNET_TIME_Relative delay; struct Neighbour *n; GNUNET_assert (NULL != h->mq); if (NULL != h->quota_task) { GNUNET_SCHEDULER_cancel (h->quota_task); h->quota_task = NULL; } if (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) { delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, n->th->notify_size + n->traffic_overhead); n->traffic_overhead = 0; } else { LOG (GNUNET_ERROR_TYPE_DEBUG, "No work to be done, not scheduling transmission.\n"); return; /* no work to be done */ } LOG (GNUNET_ERROR_TYPE_DEBUG, "Scheduling next transmission to service in %s\n", GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES)); h->quota_task = GNUNET_SCHEDULER_add_delayed (delay, &schedule_transmission_task, h); } /** * Try again to connect to transport service. * * @param cls the handle to the transport service */ static void reconnect (void *cls) { GNUNET_MQ_hd_var_size (hello, GNUNET_MESSAGE_TYPE_HELLO, struct GNUNET_MessageHeader); GNUNET_MQ_hd_fixed_size (connect, GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT, struct ConnectInfoMessage); GNUNET_MQ_hd_fixed_size (disconnect, GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT, struct DisconnectInfoMessage); GNUNET_MQ_hd_fixed_size (send_ok, GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK, struct SendOkMessage); GNUNET_MQ_hd_var_size (recv, GNUNET_MESSAGE_TYPE_TRANSPORT_RECV, struct InboundMessage); GNUNET_MQ_hd_fixed_size (set_quota, GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA, struct QuotaSetMessage); struct GNUNET_TRANSPORT_Handle *h = cls; struct GNUNET_MQ_MessageHandler handlers[] = { make_hello_handler (h), make_connect_handler (h), make_disconnect_handler (h), make_send_ok_handler (h), make_recv_handler (h), make_set_quota_handler (h), GNUNET_MQ_handler_end () }; struct GNUNET_MQ_Envelope *env; struct StartMessage *s; uint32_t options; h->reconnect_task = NULL; LOG (GNUNET_ERROR_TYPE_DEBUG, "Connecting to transport service.\n"); GNUNET_assert (NULL == h->mq); h->reconnecting = GNUNET_NO; h->mq = GNUNET_CLIENT_connecT (h->cfg, "transport", handlers, &mq_error_handler, h); if (NULL == h->mq) return; env = GNUNET_MQ_msg (s, GNUNET_MESSAGE_TYPE_TRANSPORT_START); options = 0; if (h->check_self) options |= 1; if (NULL != h->rec) options |= 2; s->options = htonl (options); s->self = h->self; GNUNET_MQ_send (h->mq, env); } /** * Function that will schedule the job that will try * to connect us again to the client. * * @param h transport service to reconnect */ static void disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h) { GNUNET_assert (NULL == h->reconnect_task); if (NULL != h->mq) { GNUNET_MQ_destroy (h->mq); h->mq = NULL; } /* Forget about all neighbours that we used to be connected to */ GNUNET_CONTAINER_multipeermap_iterate (h->neighbours, &neighbour_delete, h); if (NULL != h->quota_task) { GNUNET_SCHEDULER_cancel (h->quota_task); h->quota_task = NULL; } LOG (GNUNET_ERROR_TYPE_DEBUG, "Scheduling task to reconnect to transport service in %s.\n", GNUNET_STRINGS_relative_time_to_string (h->reconnect_delay, GNUNET_YES)); h->reconnect_task = GNUNET_SCHEDULER_add_delayed (h->reconnect_delay, &reconnect, h); h->reconnect_delay = GNUNET_TIME_STD_BACKOFF (h->reconnect_delay); } /** * Set transport metrics for a peer and a direction. * * @param handle transport handle * @param peer the peer to set the metric for * @param prop the performance metrics to set * @param delay_in inbound delay to introduce * @param delay_out outbound delay to introduce * * Note: Delay restrictions in receiving direction will be enforced * with one message delay. */ void GNUNET_TRANSPORT_set_traffic_metric (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_ATS_Properties *prop, struct GNUNET_TIME_Relative delay_in, struct GNUNET_TIME_Relative delay_out) { struct GNUNET_MQ_Envelope *env; struct TrafficMetricMessage *msg; if (NULL == handle->mq) return; env = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_TRANSPORT_TRAFFIC_METRIC); msg->reserved = htonl (0); msg->peer = *peer; GNUNET_ATS_properties_hton (&msg->properties, prop); msg->delay_in = GNUNET_TIME_relative_hton (delay_in); msg->delay_out = GNUNET_TIME_relative_hton (delay_out); GNUNET_MQ_send (handle->mq, env); } /** * Checks if a given peer is connected to us * * @param handle connection to transport service * @param peer the peer to check * @return #GNUNET_YES (connected) or #GNUNET_NO (disconnected) */ int GNUNET_TRANSPORT_check_peer_connected (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *peer) { if (GNUNET_YES == GNUNET_CONTAINER_multipeermap_contains (handle->neighbours, peer)) return GNUNET_YES; return GNUNET_NO; } /** * Connect to the transport service. Note that the connection may * complete (or fail) asynchronously. * * @param cfg configuration to use * @param self our own identity (API should check that it matches * the identity found by transport), or NULL (no check) * @param cls closure for the callbacks * @param rec receive function to call * @param nc function to call on connect events * @param nd function to call on disconnect events * @return NULL on error */ struct GNUNET_TRANSPORT_Handle * GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_PeerIdentity *self, void *cls, GNUNET_TRANSPORT_ReceiveCallback rec, GNUNET_TRANSPORT_NotifyConnect nc, GNUNET_TRANSPORT_NotifyDisconnect nd) { return GNUNET_TRANSPORT_connect2 (cfg, self, cls, rec, nc, nd, NULL); } /** * Connect to the transport service. Note that the connection may * complete (or fail) asynchronously. * * @param cfg configuration to use * @param self our own identity (API should check that it matches * the identity found by transport), or NULL (no check) * @param cls closure for the callbacks * @param rec receive function to call * @param nc function to call on connect events * @param nd function to call on disconnect events * @param neb function to call if we have excess bandwidth to a peer * @return NULL on error */ struct GNUNET_TRANSPORT_Handle * GNUNET_TRANSPORT_connect2 (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_PeerIdentity *self, void *cls, GNUNET_TRANSPORT_ReceiveCallback rec, GNUNET_TRANSPORT_NotifyConnect nc, GNUNET_TRANSPORT_NotifyDisconnect nd, GNUNET_TRANSPORT_NotifyExcessBandwidth neb) { struct GNUNET_TRANSPORT_Handle *h; h = GNUNET_new (struct GNUNET_TRANSPORT_Handle); if (NULL != self) { h->self = *self; h->check_self = GNUNET_YES; } h->cfg = cfg; h->cls = cls; h->rec = rec; h->nc_cb = nc; h->nd_cb = nd; h->neb_cb = neb; h->reconnect_delay = GNUNET_TIME_UNIT_ZERO; LOG (GNUNET_ERROR_TYPE_DEBUG, "Connecting to transport service.\n"); reconnect (h); if (NULL == h->mq) { GNUNET_free (h); return NULL; } h->neighbours = GNUNET_CONTAINER_multipeermap_create (STARTING_NEIGHBOURS_SIZE, GNUNET_YES); h->ready_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN); return h; } /** * Disconnect from the transport service. * * @param handle handle to the service as returned from #GNUNET_TRANSPORT_connect() */ void GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Transport disconnect called!\n"); /* this disconnects all neighbours... */ if (NULL == handle->reconnect_task) disconnect_and_schedule_reconnect (handle); /* and now we stop trying to connect again... */ if (NULL != handle->reconnect_task) { GNUNET_SCHEDULER_cancel (handle->reconnect_task); handle->reconnect_task = NULL; } GNUNET_CONTAINER_multipeermap_destroy (handle->neighbours); handle->neighbours = NULL; if (NULL != handle->quota_task) { GNUNET_SCHEDULER_cancel (handle->quota_task); handle->quota_task = NULL; } GNUNET_free_non_null (handle->my_hello); handle->my_hello = NULL; GNUNET_CONTAINER_heap_destroy (handle->ready_heap); handle->ready_heap = NULL; GNUNET_free (handle); } /** * Check if we could queue a message of the given size for * transmission. The transport service will take both its * internal buffers and bandwidth limits imposed by the * other peer into consideration when answering this query. * * @param handle connection to transport service * @param target who should receive the message * @param size how big is the message we want to transmit? * @param timeout after how long should we give up (and call * notify with buf NULL and size 0)? * @param notify function to call when we are ready to * send such a message * @param notify_cls closure for @a notify * @return NULL if someone else is already waiting to be notified * non-NULL if the notify callback was queued (can be used to cancel * using #GNUNET_TRANSPORT_notify_transmit_ready_cancel) */ struct GNUNET_TRANSPORT_TransmitHandle * GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *target, size_t size, struct GNUNET_TIME_Relative timeout, GNUNET_TRANSPORT_TransmitReadyNotify notify, void *notify_cls) { struct Neighbour *n; struct GNUNET_TRANSPORT_TransmitHandle *th; struct GNUNET_TIME_Relative delay; n = neighbour_find (handle, target); if (NULL == n) { /* only use this function * once a connection has been established */ GNUNET_assert (0); return NULL; } if (NULL != n->th) { /* attempt to send two messages at the same time to the same peer */ GNUNET_assert (0); return NULL; } GNUNET_assert (NULL == n->hn); th = GNUNET_new (struct GNUNET_TRANSPORT_TransmitHandle); th->neighbour = n; th->notify = notify; th->notify_cls = notify_cls; th->request_start = GNUNET_TIME_absolute_get (); th->timeout = GNUNET_TIME_relative_to_absolute (timeout); th->notify_size = size; n->th = th; /* calculate when our transmission should be ready */ delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, size + n->traffic_overhead); n->traffic_overhead = 0; if (delay.rel_value_us > timeout.rel_value_us) delay.rel_value_us = 0; /* notify immediately (with failure) */ if (delay.rel_value_us > GNUNET_CONSTANTS_LATENCY_WARN.rel_value_us) LOG (GNUNET_ERROR_TYPE_WARNING, "At bandwidth %u byte/s next transmission to %s in %s\n", (unsigned int) n->out_tracker.available_bytes_per_s__, GNUNET_i2s (target), GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES)); else LOG (GNUNET_ERROR_TYPE_DEBUG, "At bandwidth %u byte/s next transmission to %s in %s\n", (unsigned int) n->out_tracker.available_bytes_per_s__, GNUNET_i2s (target), GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES)); n->hn = GNUNET_CONTAINER_heap_insert (handle->ready_heap, n, delay.rel_value_us); schedule_transmission (handle); return th; } /** * Cancel the specified transmission-ready notification. * * @param th handle returned from #GNUNET_TRANSPORT_notify_transmit_ready() */ void GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct GNUNET_TRANSPORT_TransmitHandle *th) { struct Neighbour *n; GNUNET_assert (NULL == th->next); GNUNET_assert (NULL == th->prev); n = th->neighbour; GNUNET_assert (th == n->th); n->th = NULL; if (NULL != n->hn) { GNUNET_CONTAINER_heap_remove_node (n->hn); n->hn = NULL; } else { GNUNET_assert (NULL != th->timeout_task); GNUNET_SCHEDULER_cancel (th->timeout_task); th->timeout_task = NULL; } GNUNET_free (th); } /* end of transport_api.c */