/* This file is part of GNUnet. (C) 2009 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 transport/transport_api.c * @brief library to access the low-level P2P IO service * @author Christian Grothoff */ #include "platform.h" #include "gnunet_client_lib.h" #include "gnunet_arm_service.h" #include "gnunet_hello_lib.h" #include "gnunet_protocols.h" #include "gnunet_server_lib.h" #include "gnunet_time_lib.h" #include "gnunet_transport_service.h" #include "transport.h" /** * After how long do we give up on transmitting a HELLO * to the service? */ #define OFFER_HELLO_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30) /** * After how long do we automatically retry an unsuccessful * CONNECT request? */ #define CONNECT_RETRY_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, 750) /** * How long should ARM wait when starting up the * transport service before reporting back? */ #define START_SERVICE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5) /** * How long should ARM wait when stopping the * transport service before reporting back? */ #define STOP_SERVICE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5) /** * Entry in linked list of all of our current neighbours. */ struct NeighbourList { /** * This is a linked list. */ struct NeighbourList *next; /** * Active transmit handle, can be NULL. Used to move * from ready to wait list on disconnect and to block * two transmissions to the same peer from being scheduled * at the same time. */ struct GNUNET_TRANSPORT_TransmitHandle *transmit_handle; /** * Identity of this neighbour. */ struct GNUNET_PeerIdentity id; /** * At what time did we reset last_sent last? */ struct GNUNET_TIME_Absolute last_quota_update; /** * How many bytes have we sent since the "last_quota_update" * timestamp? */ uint64_t last_sent; /** * Quota for outbound traffic to the neighbour in bytes/ms. */ uint32_t quota_out; /** * Set to GNUNET_YES if we are currently allowed to * transmit a message to the transport service for this * peer, GNUNET_NO otherwise. */ int transmit_ok; #if ACK /** * Set to GNUNET_YES if we have received an ACK for the * given peer. Peers that receive our HELLO always respond * with an ACK to let us know that we are successfully * communicating. Note that a PING can not be used for this * since PINGs are only send if a HELLO address requires * confirmation (and also, PINGs are not passed to the * transport API itself). */ int received_ack; #endif }; /** * Linked list of requests from clients for our HELLO * that were deferred. */ struct HelloWaitList { /** * This is a linked list. */ struct HelloWaitList *next; /** * Reference back to our transport handle. */ struct GNUNET_TRANSPORT_Handle *handle; /** * Callback to call once we got our HELLO. */ GNUNET_TRANSPORT_HelloUpdateCallback rec; /** * Closure for rec. */ void *rec_cls; }; /** * Opaque handle for a transmission-ready request. */ struct GNUNET_TRANSPORT_TransmitHandle { /** * We keep the transmit handles that are waiting for * a transport-level connection in a doubly linked list. */ struct GNUNET_TRANSPORT_TransmitHandle *next; /** * We keep the transmit handles that are waiting for * a transport-level connection in a doubly linked list. */ struct GNUNET_TRANSPORT_TransmitHandle *prev; /** * Handle of the main transport data structure. */ struct GNUNET_TRANSPORT_Handle *handle; /** * Neighbour for this handle, can be NULL if the service * is not yet connected to the target. */ struct NeighbourList *neighbour; /** * Which peer is this transmission going to be for? All * zeros if it is control-traffic to the service. */ struct GNUNET_PeerIdentity target; /** * Function to call when notify_size bytes are available * for transmission. */ GNUNET_CONNECTION_TransmitReadyNotify notify; /** * Closure for notify. */ void *notify_cls; /** * transmit_ready task Id. The task is used to introduce the * artificial delay that may be required to maintain the bandwidth * limits. Later, this will be the ID of the "transmit_timeout" * task which is used to signal a timeout if the transmission could * not be done in a timely fashion. */ GNUNET_SCHEDULER_TaskIdentifier notify_delay_task; /** * Timeout for this request. */ struct GNUNET_TIME_Absolute timeout; /** * How many bytes is our notify callback waiting for? */ size_t notify_size; /** * How important is this message? */ unsigned int priority; }; /** * 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; /** * The current HELLO message for this peer. Updated * whenever transports change their addresses. */ struct GNUNET_HELLO_Message *my_hello; /** * My client connection to the transport service. */ struct GNUNET_CLIENT_Connection *client; /** * Handle to our registration with the client for notification. */ struct GNUNET_CLIENT_TransmitHandle *network_handle; /** * Linked list of transmit handles that are waiting for the * transport to connect to the respective peer. When we * receive notification that the transport connected to a * peer, we go over this list and check if someone has already * requested a transmission to the new peer; if so, we trigger * the next step. */ struct GNUNET_TRANSPORT_TransmitHandle *connect_wait_head; /** * Linked list of transmit handles that are waiting for the * transport to be ready for transmission to the respective * peer. When we * receive notification that the transport disconnected from * a peer, we go over this list and move the entry back to * the connect_wait list. */ struct GNUNET_TRANSPORT_TransmitHandle *connect_ready_head; /** * Linked list of pending requests for our HELLO. */ struct HelloWaitList *hwl_head; /** * My scheduler. */ struct GNUNET_SCHEDULER_Handle *sched; /** * My configuration. */ const struct GNUNET_CONFIGURATION_Handle *cfg; /** * Linked list of the current neighbours of this peer. */ struct NeighbourList *neighbours; /** * ID of the task trying to reconnect to the * service. */ GNUNET_SCHEDULER_TaskIdentifier reconnect_task; /** * Delay until we try to reconnect. */ struct GNUNET_TIME_Relative reconnect_delay; /** * Do we currently have a transmission pending? * (schedule transmission was called but has not * yet succeeded)? */ int transmission_scheduled; }; static struct NeighbourList * find_neighbour (struct GNUNET_TRANSPORT_Handle *h, const struct GNUNET_PeerIdentity *peer) { struct NeighbourList *pos; pos = h->neighbours; while ((pos != NULL) && (0 != memcmp (peer, &pos->id, sizeof (struct GNUNET_PeerIdentity)))) pos = pos->next; return pos; } /** * Schedule the task to send one message from the * connect_ready list to the service. */ static void schedule_transmission (struct GNUNET_TRANSPORT_Handle *h); /** * Transmit message to client... */ static size_t transport_notify_ready (void *cls, size_t size, void *buf) { struct GNUNET_TRANSPORT_Handle *h = cls; struct GNUNET_TRANSPORT_TransmitHandle *th; struct NeighbourList *n; size_t ret; char *cbuf; h->network_handle = NULL; h->transmission_scheduled = GNUNET_NO; if (buf == NULL) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Could not transmit to transport service, cancelling pending requests\n"); #endif th = h->connect_ready_head; if (th->next != NULL) th->next->prev = NULL; h->connect_ready_head = th->next; if (NULL != (n = th->neighbour)) { GNUNET_assert (n->transmit_handle == th); n->transmit_handle = NULL; } if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } if (NULL != th->notify) GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL)); GNUNET_free (th); if (h->connect_ready_head != NULL) schedule_transmission (h); /* FIXME: is this ok? */ return 0; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Ready to transmit %u bytes to transport service\n", size); #endif cbuf = buf; ret = 0; h->network_handle = NULL; h->transmission_scheduled = GNUNET_NO; while ((h->connect_ready_head != NULL) && (h->connect_ready_head->notify_size <= size)) { th = h->connect_ready_head; if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } GNUNET_assert (th->notify_size <= size); if (th->next != NULL) th->next->prev = NULL; h->connect_ready_head = th->next; if (NULL != (n = th->neighbour)) { GNUNET_assert (n->transmit_handle == th); n->transmit_handle = NULL; } if (NULL != th->notify) ret += th->notify (th->notify_cls, size, &cbuf[ret]); GNUNET_free (th); if (n != NULL) n->last_sent += ret; size -= ret; } if (h->connect_ready_head != NULL) schedule_transmission (h); #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u bytes to transport service\n", ret); #endif return ret; } /** * Schedule the task to send one message from the * connect_ready list to the service. */ static void schedule_transmission (struct GNUNET_TRANSPORT_Handle *h) { struct GNUNET_TRANSPORT_TransmitHandle *th; GNUNET_assert (NULL == h->network_handle); if (h->client == NULL) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Could not yet schedule transmission: we are not yet connected to the transport service!\n"); return; /* not yet connected */ } th = h->connect_ready_head; if (th == NULL) return; /* no request pending */ if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { /* remove existing time out task, will be integrated with transmit_ready notification! */ GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } h->transmission_scheduled = GNUNET_YES; h->network_handle = GNUNET_CLIENT_notify_transmit_ready (h->client, th->notify_size, GNUNET_TIME_absolute_get_remaining (th->timeout), GNUNET_NO, &transport_notify_ready, h); GNUNET_assert (NULL != h->network_handle); } /** * Insert the given transmit handle in the given sorted * doubly linked list based on timeout. * * @param head pointer to the head of the linked list * @param th element to insert into the list */ static void insert_transmit_handle (struct GNUNET_TRANSPORT_TransmitHandle **head, struct GNUNET_TRANSPORT_TransmitHandle *th) { struct GNUNET_TRANSPORT_TransmitHandle *pos; struct GNUNET_TRANSPORT_TransmitHandle *prev; pos = *head; prev = NULL; while ((pos != NULL) && (pos->timeout.value < th->timeout.value)) { prev = pos; pos = pos->next; } if (prev == NULL) { th->next = *head; if (th->next != NULL) th->next->prev = th; *head = th; } else { th->next = pos; th->prev = prev; prev->next = th; if (pos != NULL) pos->prev = th; } } /** * Cancel a pending notify delay task (if pending) and also remove the * given transmit handle from whatever list is on. * * @param th handle for the transmission request to manipulate */ static void remove_from_any_list (struct GNUNET_TRANSPORT_TransmitHandle *th) { struct GNUNET_TRANSPORT_Handle *h; h = th->handle; if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } if (th->prev == NULL) { if (th == h->connect_wait_head) h->connect_wait_head = th->next; else h->connect_ready_head = th->next; } else { th->prev->next = th->next; } if (th->next != NULL) th->next->prev = th->prev; } /** * Schedule a request to connect to the given * neighbour (and if successful, add the specified * handle to the wait list). * * @param th handle for a request to transmit once we * have connected */ static void try_connect (struct GNUNET_TRANSPORT_TransmitHandle *th); /** * Called when our transmit request timed out before any transport * reported success connecting to the desired peer or before the * transport was ready to receive. Signal error and free * TransmitHandle. */ static void peer_transmit_timeout (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct GNUNET_TRANSPORT_TransmitHandle *th = cls; th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; if (th->neighbour != NULL) th->neighbour->transmit_handle = NULL; #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Request for transmission to peer `%s' timed out.\n", GNUNET_i2s (&th->target)); #endif remove_from_any_list (th); if (NULL != th->notify) th->notify (th->notify_cls, 0, NULL); GNUNET_free (th); } /** * Queue control request for transmission to the transport * service. * * @param h handle to the transport service * @param size number of bytes to be transmitted * @param at_head request must be added to the head of the queue * (otherwise request will be appended) * @param timeout how long this transmission can wait (at most) * @param notify function to call to get the content * @param notify_cls closure for notify */ static void schedule_control_transmit (struct GNUNET_TRANSPORT_Handle *h, size_t size, int at_head, struct GNUNET_TIME_Relative timeout, GNUNET_CONNECTION_TransmitReadyNotify notify, void *notify_cls) { struct GNUNET_TRANSPORT_TransmitHandle *th; #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Control transmit of %u bytes within %llums requested\n", size, (unsigned long long) timeout.value); #endif th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle)); th->handle = h; th->notify = notify; th->notify_cls = notify_cls; th->timeout = GNUNET_TIME_relative_to_absolute (timeout); th->notify_size = size; th->notify_delay_task = GNUNET_SCHEDULER_add_delayed (h->sched, timeout, &peer_transmit_timeout, th); if (at_head) { th->next = h->connect_ready_head; h->connect_ready_head = th; if (th->next != NULL) th->next->prev = th; } else { insert_transmit_handle (&h->connect_ready_head, th); } if (GNUNET_NO == h->transmission_scheduled) schedule_transmission (h); } /** * Update the quota values for the given neighbour now. */ static void update_quota (struct NeighbourList *n) { struct GNUNET_TIME_Relative delta; uint64_t allowed; uint64_t remaining; delta = GNUNET_TIME_absolute_get_duration (n->last_quota_update); allowed = delta.value * n->quota_out; if (n->last_sent < allowed) { remaining = allowed - n->last_sent; if (n->quota_out > 0) remaining /= n->quota_out; else remaining = 0; if (remaining > MAX_BANDWIDTH_CARRY) remaining = MAX_BANDWIDTH_CARRY; n->last_sent = 0; n->last_quota_update = GNUNET_TIME_absolute_get (); n->last_quota_update.value -= remaining; } else { n->last_sent -= allowed; n->last_quota_update = GNUNET_TIME_absolute_get (); } } struct SetQuotaContext { struct GNUNET_TRANSPORT_Handle *handle; struct GNUNET_PeerIdentity target; GNUNET_SCHEDULER_Task cont; void *cont_cls; struct GNUNET_TIME_Absolute timeout; uint32_t quota_in; }; static size_t send_set_quota (void *cls, size_t size, void *buf) { struct SetQuotaContext *sqc = cls; struct QuotaSetMessage *msg; if (buf == NULL) { GNUNET_SCHEDULER_add_continuation (sqc->handle->sched, sqc->cont, sqc->cont_cls, GNUNET_SCHEDULER_REASON_TIMEOUT); GNUNET_free (sqc); return 0; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request with respect to `%4s'.\n", "SET_QUOTA", GNUNET_i2s (&sqc->target)); #endif GNUNET_assert (size >= sizeof (struct QuotaSetMessage)); msg = buf; msg->header.size = htons (sizeof (struct QuotaSetMessage)); msg->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA); msg->quota_in = htonl (sqc->quota_in); memcpy (&msg->peer, &sqc->target, sizeof (struct GNUNET_PeerIdentity)); if (sqc->cont != NULL) GNUNET_SCHEDULER_add_continuation (sqc->handle->sched, sqc->cont, sqc->cont_cls, GNUNET_SCHEDULER_REASON_PREREQ_DONE); GNUNET_free (sqc); return sizeof (struct QuotaSetMessage); } /** * Set the share of incoming bandwidth for the given * peer to the specified amount. * * @param handle connection to transport service * @param target who's bandwidth quota is being changed * @param quota_in incoming bandwidth quota in bytes per ms * @param quota_out outgoing bandwidth quota in bytes per ms * @param timeout how long to wait until signaling failure if * we can not communicate the quota change * @param cont continuation to call when done, will be called * either with reason "TIMEOUT" or with reason "PREREQ_DONE" * @param cont_cls closure for continuation */ void GNUNET_TRANSPORT_set_quota (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *target, uint32_t quota_in, uint32_t quota_out, struct GNUNET_TIME_Relative timeout, GNUNET_SCHEDULER_Task cont, void *cont_cls) { struct NeighbourList *n; struct SetQuotaContext *sqc; n = find_neighbour (handle, target); if (n != NULL) { update_quota (n); if (n->quota_out < quota_out) n->last_quota_update = GNUNET_TIME_absolute_get (); n->quota_out = quota_out; } sqc = GNUNET_malloc (sizeof (struct SetQuotaContext)); sqc->handle = handle; sqc->target = *target; sqc->cont = cont; sqc->cont_cls = cont_cls; sqc->timeout = GNUNET_TIME_relative_to_absolute (timeout); sqc->quota_in = quota_in; schedule_control_transmit (handle, sizeof (struct QuotaSetMessage), GNUNET_NO, timeout, &send_set_quota, sqc); } /** * Obtain the HELLO message for this peer. * * @param handle connection to transport service * @param timeout how long to wait for the HELLO * @param rec function to call with the HELLO, sender will be our peer * identity; message and sender will be NULL on timeout * (handshake with transport service pending/failed). * cost estimate will be 0. * @param rec_cls closure for rec */ void GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle, GNUNET_TRANSPORT_HelloUpdateCallback rec, void *rec_cls) { struct HelloWaitList *hwl; hwl = GNUNET_malloc (sizeof (struct HelloWaitList)); hwl->next = handle->hwl_head; handle->hwl_head = hwl; hwl->handle = handle; hwl->rec = rec; hwl->rec_cls = rec_cls; if (handle->my_hello == NULL) return; rec (rec_cls, (const struct GNUNET_MessageHeader *) handle->my_hello); } /** * Stop receiving updates about changes to our HELLO message. * * @param handle connection to transport service * @param rec function previously registered to be called with the HELLOs * @param rec_cls closure for rec */ void GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_Handle *handle, GNUNET_TRANSPORT_HelloUpdateCallback rec, void *rec_cls) { struct HelloWaitList *pos; struct HelloWaitList *prev; prev = NULL; pos = handle->hwl_head; while (pos != NULL) { if ( (pos->rec == rec) && (pos->rec_cls == rec_cls) ) break; prev = pos; pos = pos->next; } GNUNET_break (pos != NULL); if (pos == NULL) return; if (prev == NULL) handle->hwl_head = pos->next; else prev->next = pos->next; GNUNET_free (pos); } static size_t send_hello (void *cls, size_t size, void *buf) { struct GNUNET_MessageHeader *hello = cls; uint16_t msize; if (buf == NULL) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Timeout while trying to transmit `%s' request.\n", "HELLO"); #endif GNUNET_free (hello); return 0; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "HELLO"); #endif msize = ntohs (hello->size); GNUNET_assert (size >= msize); memcpy (buf, hello, msize); GNUNET_free (hello); return msize; } /** * Offer the transport service the HELLO of another peer. Note that * the transport service may just ignore this message if the HELLO is * malformed or useless due to our local configuration. * * @param handle connection to transport service * @param hello the hello message */ void GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_MessageHeader *hello) { struct GNUNET_MessageHeader *hc; uint16_t size; if (handle->client == NULL) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Not connected to transport service, dropping offered HELLO\n"); #endif return; } GNUNET_break (ntohs (hello->type) == GNUNET_MESSAGE_TYPE_HELLO); size = ntohs (hello->size); GNUNET_break (size >= sizeof (struct GNUNET_MessageHeader)); hc = GNUNET_malloc (size); memcpy (hc, hello, size); schedule_control_transmit (handle, size, GNUNET_NO, OFFER_HELLO_TIMEOUT, &send_hello, hc); } /** * Function we use for handling incoming messages. */ static void demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg); static size_t send_start (void *cls, size_t size, void *buf) { struct GNUNET_MessageHeader *s = buf; if (buf == NULL) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Timeout while trying to transmit `%s' request.\n", "START"); #endif return 0; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "START"); #endif GNUNET_assert (size >= sizeof (struct GNUNET_MessageHeader)); s->size = htons (sizeof (struct GNUNET_MessageHeader)); s->type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_START); return sizeof (struct GNUNET_MessageHeader); } /** * We're ready to transmit the request that the transport service * should connect to a new peer. In addition to sending the * request, schedule the next phase for the transmission processing * that caused the connect request in the first place. */ static size_t request_connect (void *cls, size_t size, void *buf) { struct GNUNET_TRANSPORT_TransmitHandle *th = cls; struct TryConnectMessage *tcm; struct GNUNET_TRANSPORT_Handle *h; GNUNET_assert (th->notify_delay_task == GNUNET_SCHEDULER_NO_TASK); h = th->handle; if (buf == NULL) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Failed to transmit `%s' request for `%4s' to service.\n", "TRY_CONNECT", GNUNET_i2s (&th->target)); #endif if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } if (NULL != th->notify) GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL)); GNUNET_free (th); return 0; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' message for `%4s' (need connection in %llu ms).\n", "TRY_CONNECT", GNUNET_i2s (&th->target), GNUNET_TIME_absolute_get_remaining (th->timeout).value); #endif GNUNET_assert (size >= sizeof (struct TryConnectMessage)); tcm = buf; tcm->header.size = htons (sizeof (struct TryConnectMessage)); tcm->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TRY_CONNECT); tcm->reserved = htonl (0); memcpy (&tcm->peer, &th->target, sizeof (struct GNUNET_PeerIdentity)); th->notify_delay_task = GNUNET_SCHEDULER_add_delayed (h->sched, GNUNET_TIME_absolute_get_remaining (th->timeout), &peer_transmit_timeout, th); insert_transmit_handle (&h->connect_wait_head, th); return sizeof (struct TryConnectMessage); } /** * Schedule a request to connect to the given * neighbour (and if successful, add the specified * handle to the wait list). * * @param th handle for a request to transmit once we * have connected */ static void try_connect (struct GNUNET_TRANSPORT_TransmitHandle *th) { GNUNET_assert (th->notify_delay_task == GNUNET_SCHEDULER_NO_TASK); schedule_control_transmit (th->handle, sizeof (struct TryConnectMessage), GNUNET_NO, GNUNET_TIME_absolute_get_remaining (th->timeout), &request_connect, th); } /** * Task for delayed attempts to reconnect to a peer. * * @param cls must be a transmit handle that determines the peer * to which we will try to connect * @param tc scheduler information about why we were triggered (not used) */ static void try_connect_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct GNUNET_TRANSPORT_TransmitHandle *th = cls; th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; try_connect (th); } /** * Remove neighbour from our list. Will automatically * trigger a re-connect attempt if we have messages pending * for this peer. * * @param h our state * @param peer the peer to remove */ static void remove_neighbour (struct GNUNET_TRANSPORT_Handle *h, const struct GNUNET_PeerIdentity *peer) { struct NeighbourList *prev; struct NeighbourList *pos; struct GNUNET_TRANSPORT_TransmitHandle *th; #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Removing neighbour `%s' from list of connected peers.\n", GNUNET_i2s (peer)); #endif prev = NULL; pos = h->neighbours; while ((pos != NULL) && (0 != memcmp (peer, &pos->id, sizeof (struct GNUNET_PeerIdentity)))) { prev = pos; pos = pos->next; } if (pos == NULL) { GNUNET_break (0); return; } if (prev == NULL) h->neighbours = pos->next; else prev->next = pos->next; if (NULL != (th = pos->transmit_handle)) { pos->transmit_handle = NULL; th->neighbour = NULL; remove_from_any_list (th); if (GNUNET_TIME_absolute_get_remaining (th->timeout).value <= CONNECT_RETRY_TIMEOUT.value) { /* signal error */ GNUNET_log (GNUNET_ERROR_TYPE_INFO, _ ("Connection with `%4s' failed and timeout was in the past, giving up on message delivery.\n"), GNUNET_i2s (peer)); GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == th->notify_delay_task); peer_transmit_timeout (th, NULL); } else { GNUNET_log (GNUNET_ERROR_TYPE_INFO, _ ("Connection with `%4s' failed, will keep trying for %llu ms to deliver message\n"), GNUNET_i2s (peer), GNUNET_TIME_absolute_get_remaining (th->timeout).value); /* try again in a bit */ GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_add_delayed (h->sched, CONNECT_RETRY_TIMEOUT, &try_connect_task, th); } } if (h->nc_cb != NULL) h->nd_cb (h->cls, peer); GNUNET_free (pos); } /** * Try again to connect to transport service. */ static void reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct GNUNET_TRANSPORT_Handle *h = cls; struct GNUNET_TRANSPORT_TransmitHandle *pos; struct NeighbourList *n; /* Forget about all neighbours that we used to be connected to */ while (NULL != (n = h->neighbours)) remove_neighbour (h, &n->id); #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connecting to transport service.\n"); #endif GNUNET_assert (h->client == NULL); h->reconnect_task = GNUNET_SCHEDULER_NO_TASK; h->client = GNUNET_CLIENT_connect (h->sched, "transport", h->cfg); GNUNET_assert (h->client != NULL); /* make sure we don't send "START" twice, remove existing entry from queue (if present) */ pos = h->connect_ready_head; while (pos != NULL) { if (pos->notify == &send_start) { if (pos->prev == NULL) h->connect_ready_head = pos->next; else pos->prev->next = pos->next; if (pos->next != NULL) pos->next->prev = pos->prev; GNUNET_assert (pos->neighbour == NULL); if (GNUNET_SCHEDULER_NO_TASK != pos->notify_delay_task) { GNUNET_SCHEDULER_cancel (h->sched, pos->notify_delay_task); pos->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } GNUNET_free (pos); break; } pos = pos->next; } schedule_control_transmit (h, sizeof (struct GNUNET_MessageHeader), GNUNET_YES, GNUNET_TIME_UNIT_FOREVER_REL, &send_start, NULL); GNUNET_CLIENT_receive (h->client, &demultiplexer, h, GNUNET_TIME_UNIT_FOREVER_REL); } /** * Function that will schedule the job that will try * to connect us again to the client. */ static void schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Scheduling task to reconnect to transport service in %llu ms.\n", h->reconnect_delay.value); #endif GNUNET_assert (h->client == NULL); GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK); h->reconnect_task = GNUNET_SCHEDULER_add_delayed (h->sched, h->reconnect_delay, &reconnect, h); h->reconnect_delay = GNUNET_TIME_UNIT_SECONDS; } /** * We are connected to the respective peer, check the * bandwidth limits and schedule the transmission. */ static void schedule_request (struct GNUNET_TRANSPORT_TransmitHandle *th); /** * Function called by the scheduler when the timeout * for bandwidth availablility for the target * neighbour is reached. */ static void transmit_ready (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct GNUNET_TRANSPORT_TransmitHandle *th = cls; th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; schedule_request (th); } /** * Remove the given transmit handle from the wait list. Does NOT free * it. */ static void remove_from_wait_list (struct GNUNET_TRANSPORT_TransmitHandle *th) { if (th->prev == NULL) th->handle->connect_wait_head = th->next; else th->prev->next = th->next; if (th->next != NULL) th->next->prev = th->prev; } /** * We are connected to the respective peer, check the * bandwidth limits and schedule the transmission. */ static void schedule_request (struct GNUNET_TRANSPORT_TransmitHandle *th) { struct GNUNET_TRANSPORT_Handle *h; struct GNUNET_TIME_Relative duration; struct NeighbourList *n; uint64_t available; h = th->handle; n = th->neighbour; if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } /* check outgoing quota */ duration = GNUNET_TIME_absolute_get_duration (n->last_quota_update); if (duration.value > MIN_QUOTA_REFRESH_TIME) { update_quota (n); duration = GNUNET_TIME_absolute_get_duration (n->last_quota_update); } available = duration.value * n->quota_out; if (available < n->last_sent + th->notify_size) { /* calculate how much bandwidth we'd still need to accumulate and based on that how long we'll have to wait... */ available = n->last_sent + th->notify_size - available; duration = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, available / n->quota_out); if (th->timeout.value < GNUNET_TIME_relative_to_absolute (duration).value) { /* signal timeout! */ #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Would need %llu ms before bandwidth is available for delivery to `%4s', that is too long. Signaling timeout.\n", duration.value, GNUNET_i2s (&th->target)); #endif remove_from_wait_list (th); if (NULL != th->notify) GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL)); GNUNET_free (th); return; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Need more bandwidth, delaying delivery to `%4s' by %llu ms\n", GNUNET_i2s (&th->target), duration.value); #endif th->notify_delay_task = GNUNET_SCHEDULER_add_delayed (h->sched, duration, &transmit_ready, th); return; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Bandwidth available for transmission to `%4s'\n", GNUNET_i2s (&n->id)); #endif if (GNUNET_NO == n->transmit_ok) { /* we may be ready, but transport service is not; wait for SendOkMessage or timeout */ #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Need to wait for transport service `%s' message\n", "SEND_OK"); #endif th->notify_delay_task = GNUNET_SCHEDULER_add_delayed (h->sched, GNUNET_TIME_absolute_get_remaining (th->timeout), &peer_transmit_timeout, th); return; } n->transmit_ok = GNUNET_NO; remove_from_wait_list (th); #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Moving message for `%4s' to ready list\n", GNUNET_i2s (&n->id)); #endif insert_transmit_handle (&h->connect_ready_head, th); if (GNUNET_NO == h->transmission_scheduled) schedule_transmission (h); } /** * Add neighbour to our list */ static void add_neighbour (struct GNUNET_TRANSPORT_Handle *h, uint32_t quota_out, struct GNUNET_TIME_Relative latency, uint16_t distance, const struct GNUNET_PeerIdentity *pid) { struct NeighbourList *n; struct GNUNET_TRANSPORT_TransmitHandle *prev; struct GNUNET_TRANSPORT_TransmitHandle *pos; struct GNUNET_TRANSPORT_TransmitHandle *next; /* check for duplicates */ if (NULL != find_neighbour (h, pid)) { GNUNET_break (0); return; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Creating entry for new neighbour `%4s'.\n", GNUNET_i2s (pid)); #endif n = GNUNET_malloc (sizeof (struct NeighbourList)); n->id = *pid; n->last_quota_update = GNUNET_TIME_absolute_get (); n->quota_out = quota_out; n->next = h->neighbours; n->transmit_ok = GNUNET_YES; h->neighbours = n; if (h->nc_cb != NULL) h->nc_cb (h->cls, &n->id, latency, distance); prev = NULL; pos = h->connect_wait_head; while (pos != NULL) { next = pos->next; if (0 == memcmp (pid, &pos->target, sizeof (struct GNUNET_PeerIdentity))) { pos->neighbour = n; GNUNET_assert (NULL == n->transmit_handle); n->transmit_handle = pos; if (prev == NULL) h->connect_wait_head = next; else prev->next = next; #if ACK if (GNUNET_YES == n->received_ack) { #endif #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Found pending request for `%4s' will trigger it now.\n", GNUNET_i2s (&pos->target)); #endif if (pos->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (h->sched, pos->notify_delay_task); pos->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } schedule_request (pos); #if ACK } #endif break; } prev = pos; pos = next; } } /** * Connect to the transport service. Note that the connection may * complete (or fail) asynchronously. * * @param sched scheduler to use * @param cfg configuration to use * @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 */ struct GNUNET_TRANSPORT_Handle * GNUNET_TRANSPORT_connect (struct GNUNET_SCHEDULER_Handle *sched, const struct GNUNET_CONFIGURATION_Handle *cfg, void *cls, GNUNET_TRANSPORT_ReceiveCallback rec, GNUNET_TRANSPORT_NotifyConnect nc, GNUNET_TRANSPORT_NotifyDisconnect nd) { struct GNUNET_TRANSPORT_Handle *ret; GNUNET_ARM_start_services (cfg, sched, "peerinfo", "transport", NULL); ret = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_Handle)); ret->sched = sched; ret->cfg = cfg; ret->cls = cls; ret->rec = rec; ret->nc_cb = nc; ret->nd_cb = nd; ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO; schedule_reconnect (ret); return ret; } /** * Disconnect from the transport service. */ void GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle) { struct GNUNET_TRANSPORT_TransmitHandle *th; struct NeighbourList *n; struct HelloWaitList *hwl; struct GNUNET_CLIENT_Connection *client; #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transport disconnect called!\n"); #endif while (NULL != (th = handle->connect_ready_head)) { handle->connect_ready_head = th->next; if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (handle->sched, th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } if (NULL != th->notify) GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL)); GNUNET_free (th); } while (NULL != (th = handle->connect_wait_head)) { handle->connect_wait_head = th->next; if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (handle->sched, th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } if (NULL != th->notify) GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL)); GNUNET_free (th); } while (NULL != (n = handle->neighbours)) { handle->neighbours = n->next; if (NULL != (th = n->transmit_handle)) { if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (handle->sched, th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } if (NULL != th->notify) GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL)); GNUNET_free (th); } GNUNET_free (n); } while (NULL != (hwl = handle->hwl_head)) { handle->hwl_head = hwl->next; GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _ ("Disconnect while notification for `%s' still registered.\n"), "HELLO"); if (hwl->rec != NULL) hwl->rec (hwl->rec_cls, NULL); GNUNET_free (hwl); } if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (handle->sched, handle->reconnect_task); handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK; } GNUNET_free_non_null (handle->my_hello); handle->my_hello = NULL; GNUNET_ARM_stop_services (handle->cfg, handle->sched, "transport", "peerinfo", NULL); if (NULL != handle->network_handle) { GNUNET_CLIENT_notify_transmit_ready_cancel (handle->network_handle); handle->network_handle = NULL; } if (NULL != (client = handle->client)) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Disconnecting from transport service for good.\n"); #endif handle->client = NULL; GNUNET_CLIENT_disconnect (client); } GNUNET_free (handle); } /** * Type of a function to call when we receive a message * from the service. * * @param cls closure * @param msg message received, NULL on timeout or fatal error */ static void demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg) { struct GNUNET_TRANSPORT_Handle *h = cls; const struct DisconnectInfoMessage *dim; const struct ConnectInfoMessage *cim; const struct InboundMessage *im; const struct GNUNET_MessageHeader *imm; const struct SendOkMessage *okm; struct HelloWaitList *hwl; struct HelloWaitList *next_hwl; struct NeighbourList *n; struct GNUNET_PeerIdentity me; struct GNUNET_TRANSPORT_TransmitHandle *th; struct GNUNET_TRANSPORT_TransmitHandle *prev; struct GNUNET_TRANSPORT_TransmitHandle *pos; struct GNUNET_TRANSPORT_TransmitHandle *next; uint16_t size; if ((msg == NULL) || (h->client == NULL)) { if (h->client != NULL) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Error receiving from transport service, disconnecting temporarily.\n"); #endif if (h->network_handle != NULL) { GNUNET_CLIENT_notify_transmit_ready_cancel (h->network_handle); h->network_handle = NULL; h->transmission_scheduled = GNUNET_NO; th = h->connect_ready_head; /* add timeout again, we canceled the transmit_ready task! */ /*GNUNET_assert (th->notify_delay_task == GNUNET_SCHEDULER_NO_TASK);*/ /* START - somehow we are getting here when th->notify_delay_task is already * set. Not sure why, so just checking and canceling instead of asserting and * dying. Probably not a *fix*. */ if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task); th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } /* END */ GNUNET_assert (th->notify_delay_task == GNUNET_SCHEDULER_NO_TASK); th->notify_delay_task = GNUNET_SCHEDULER_add_delayed (h->sched, GNUNET_TIME_absolute_get_remaining (th->timeout), &peer_transmit_timeout, th); } GNUNET_CLIENT_disconnect (h->client); h->client = NULL; schedule_reconnect (h); } else { /* shutdown initiated from 'GNUNET_TRANSPORT_disconnect', finish clean up work! */ GNUNET_free (h); } return; } GNUNET_CLIENT_receive (h->client, &demultiplexer, h, GNUNET_TIME_UNIT_FOREVER_REL); size = ntohs (msg->size); switch (ntohs (msg->type)) { case GNUNET_MESSAGE_TYPE_HELLO: if (GNUNET_OK != GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg, &me)) { GNUNET_break (0); break; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Receiving (my own) `%s' message, I am `%4s'.\n", "HELLO", GNUNET_i2s (&me)); #endif GNUNET_free_non_null (h->my_hello); h->my_hello = NULL; if (size < sizeof (struct GNUNET_MessageHeader)) { GNUNET_break (0); break; } h->my_hello = GNUNET_malloc (size); memcpy (h->my_hello, msg, size); hwl = h->hwl_head; while (NULL != hwl) { next_hwl = hwl->next; hwl->rec (hwl->rec_cls, (const struct GNUNET_MessageHeader *) h->my_hello); hwl = next_hwl; } break; case GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT: if (size != sizeof (struct ConnectInfoMessage)) { GNUNET_break (0); break; } cim = (const struct ConnectInfoMessage *) msg; #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n", "CONNECT", GNUNET_i2s (&cim->id)); #endif if (NULL == (n = find_neighbour(h, &cim->id))) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Don't know neighbor, adding!\n"); #endif add_neighbour (h, ntohl (cim->quota_out), GNUNET_TIME_relative_ntoh (cim->latency), ntohs(cim->distance), &cim->id); } else { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Do know neighbor, scheduling transmission!\n"); #endif #if ACK n->received_ack = GNUNET_YES; #endif if (NULL != n->transmit_handle) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Peer connected, scheduling delayed message for delivery now.\n"); #endif schedule_request (n->transmit_handle); } else { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmit handle is null... Checking for pending stuff(?)\n"); #endif prev = NULL; pos = h->connect_wait_head; while (pos != NULL) { next = pos->next; if (0 == memcmp (&cim->id, &pos->target, sizeof (struct GNUNET_PeerIdentity))) { pos->neighbour = n; GNUNET_assert (NULL == n->transmit_handle); n->transmit_handle = pos; if (prev == NULL) h->connect_wait_head = next; else prev->next = next; #if ACK if (GNUNET_YES == n->received_ack) { #endif #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Found pending request for `%4s' will trigger it now.\n", GNUNET_i2s (&pos->target)); #endif if (pos->notify_delay_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (h->sched, pos->notify_delay_task); pos->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; } schedule_request (pos); #if ACK } #endif break; } prev = pos; pos = next; } } } break; case GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT: if (size != sizeof (struct DisconnectInfoMessage)) { GNUNET_break (0); break; } dim = (const struct DisconnectInfoMessage *) msg; #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n", "DISCONNECT", GNUNET_i2s (&dim->peer)); #endif remove_neighbour (h, &dim->peer); break; case GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK: if (size != sizeof (struct SendOkMessage)) { GNUNET_break (0); break; } okm = (const struct SendOkMessage *) msg; #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message, transmission %s.\n", "SEND_OK", ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed"); #endif n = find_neighbour (h, &okm->peer); GNUNET_assert (n != NULL); n->transmit_ok = GNUNET_YES; if (n->transmit_handle != NULL) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Processing pending message for `%4s'\n", GNUNET_i2s (&n->id)); #endif GNUNET_SCHEDULER_cancel (h->sched, n->transmit_handle->notify_delay_task); n->transmit_handle->notify_delay_task = GNUNET_SCHEDULER_NO_TASK; schedule_request (n->transmit_handle); } break; case GNUNET_MESSAGE_TYPE_TRANSPORT_RECV: #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "RECV"); #endif if (size < sizeof (struct InboundMessage) + sizeof (struct GNUNET_MessageHeader)) { GNUNET_break (0); break; } im = (const struct InboundMessage *) msg; imm = (const struct GNUNET_MessageHeader *) &im[1]; if (ntohs (imm->size) + sizeof (struct InboundMessage) != size) { GNUNET_break (0); break; } switch (ntohs (imm->type)) { case GNUNET_MESSAGE_TYPE_TRANSPORT_ACK: #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message from `%4s'.\n", "ACK", GNUNET_i2s (&im->peer)); #endif break; default: #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received message of type %u from `%4s'.\n", ntohs (imm->type), GNUNET_i2s (&im->peer)); #endif n = find_neighbour (h, &im->peer); if (n == NULL) { GNUNET_break (0); break; } if (NULL != n->transmit_handle) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Peer connected, scheduling delayed message for delivery now.\n"); #endif schedule_request (n->transmit_handle); } if (h->rec != NULL) h->rec (h->cls, &im->peer, imm, GNUNET_TIME_relative_ntoh (im->latency), ntohs(im->distance)); break; } break; default: GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _ ("Received unexpected message of type %u in %s:%u\n"), ntohs (msg->type), __FILE__, __LINE__); GNUNET_break (0); break; } } struct ClientTransmitWrapper { GNUNET_CONNECTION_TransmitReadyNotify notify; void *notify_cls; struct GNUNET_TRANSPORT_TransmitHandle *th; }; /** * Transmit message of a client destined for another * peer to the service. */ static size_t client_notify_wrapper (void *cls, size_t size, void *buf) { struct ClientTransmitWrapper *ctw = cls; struct OutboundMessage *obm; struct GNUNET_MessageHeader *hdr; size_t ret; if (size == 0) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmission request could not be satisfied.\n"); #endif if (NULL != ctw->notify) GNUNET_assert (0 == ctw->notify (ctw->notify_cls, 0, NULL)); GNUNET_free (ctw); return 0; } GNUNET_assert (size >= sizeof (struct OutboundMessage)); obm = buf; if (ctw->notify != NULL) ret = ctw->notify (ctw->notify_cls, size - sizeof (struct OutboundMessage), (void *) &obm[1]); else ret = 0; if (ret == 0) { /* Need to reset flag, no SEND means no SEND_OK! */ ctw->th->neighbour->transmit_ok = GNUNET_YES; GNUNET_free (ctw); return 0; } GNUNET_assert (ret >= sizeof (struct GNUNET_MessageHeader)); hdr = (struct GNUNET_MessageHeader *) &obm[1]; GNUNET_assert (ntohs (hdr->size) == ret); GNUNET_assert (ret + sizeof (struct OutboundMessage) < GNUNET_SERVER_MAX_MESSAGE_SIZE); #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' message with data for `%4s'\n", "SEND", GNUNET_i2s (&ctw->th->target)); #endif ret += sizeof (struct OutboundMessage); obm->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND); obm->header.size = htons (ret); obm->priority = htonl (ctw->th->priority); obm->peer = ctw->th->target; GNUNET_free (ctw); return ret; } /** * 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 priority how important is the message? * @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 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, unsigned int priority, struct GNUNET_TIME_Relative timeout, GNUNET_CONNECTION_TransmitReadyNotify notify, void *notify_cls) { struct GNUNET_TRANSPORT_TransmitHandle *pos; struct GNUNET_TRANSPORT_TransmitHandle *th; struct NeighbourList *n; struct ClientTransmitWrapper *ctw; if (size + sizeof (struct OutboundMessage) >= GNUNET_SERVER_MAX_MESSAGE_SIZE) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Message size is %d, max allowed is %d.\n", size + sizeof (struct OutboundMessage), GNUNET_SERVER_MAX_MESSAGE_SIZE); #endif GNUNET_break (0); return NULL; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Asking transport service for transmission of %u bytes to peer `%4s'.\n", size, GNUNET_i2s (target)); #endif n = find_neighbour (handle, target); if ((n != NULL) && (n->transmit_handle != NULL)) return NULL; /* already have a request pending for this peer! */ ctw = GNUNET_malloc (sizeof (struct ClientTransmitWrapper)); th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle)); ctw->notify = notify; ctw->notify_cls = notify_cls; ctw->th = th; th->handle = handle; th->neighbour = n; th->target = *target; th->notify = &client_notify_wrapper; th->notify_cls = ctw; th->timeout = GNUNET_TIME_relative_to_absolute (timeout); th->notify_size = size + sizeof (struct OutboundMessage); th->priority = priority; if (NULL == n) { pos = handle->connect_wait_head; while (pos != NULL) { GNUNET_assert (0 != memcmp (target, &pos->target, sizeof (struct GNUNET_PeerIdentity))); pos = pos->next; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Will now try to connect to `%4s'.\n", GNUNET_i2s (target)); #endif try_connect (th); return th; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmission request queued for transmission to transport service.\n"); #endif GNUNET_assert (NULL == n->transmit_handle); n->transmit_handle = th; if (GNUNET_YES != n->transmit_ok) { #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connection to `%4s' is not yet confirmed connected, scheduling timeout (%llu ms) only.\n", GNUNET_i2s (target), timeout.value); #endif th->notify_delay_task = GNUNET_SCHEDULER_add_delayed (handle->sched, timeout, &peer_transmit_timeout, th); return th; } #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Peer `%4s' is ready to receive, scheduling message for delivery now.\n", GNUNET_i2s (target)); #endif th->notify_delay_task = GNUNET_SCHEDULER_add_now (handle->sched, &transmit_ready, th); return th; } /** * Cancel the specified transmission-ready notification. */ void GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct GNUNET_TRANSPORT_TransmitHandle *th) { struct GNUNET_TRANSPORT_Handle *h; #if DEBUG_TRANSPORT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmission request of %u bytes to `%4s' was cancelled.\n", th->notify_size - sizeof (struct OutboundMessage), GNUNET_i2s (&th->target)); #endif GNUNET_assert (th->notify == &client_notify_wrapper); remove_from_any_list (th); h = th->handle; if ((h->connect_ready_head == NULL) && (h->network_handle != NULL)) { GNUNET_CLIENT_notify_transmit_ready_cancel (h->network_handle); h->network_handle = NULL; h->transmission_scheduled = GNUNET_NO; } GNUNET_free (th->notify_cls); GNUNET_assert (th->notify_delay_task == GNUNET_SCHEDULER_NO_TASK); GNUNET_free (th); } /* end of transport_api.c */