/* This file is part of GNUnet. Copyright (C) 2011, 2017 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 cadet/cadet_api.c * @brief cadet api: client implementation of cadet service * @author Bartlomiej Polot * @author Christian Grothoff */ #include "platform.h" #include "gnunet_util_lib.h" #include "gnunet_constants.h" #include "gnunet_cadet_service.h" #include "cadet.h" #include "cadet_protocol.h" #define LOG(kind,...) GNUNET_log_from (kind, "cadet-api",__VA_ARGS__) /** * Ugly legacy hack. */ union CadetInfoCB { /** * Channel callback. */ GNUNET_CADET_ChannelCB channel_cb; /** * Monitor callback */ GNUNET_CADET_PeersCB peers_cb; /** * Monitor callback */ GNUNET_CADET_PeerCB peer_cb; /** * Monitor callback */ GNUNET_CADET_TunnelsCB tunnels_cb; /** * Tunnel callback. */ GNUNET_CADET_TunnelCB tunnel_cb; }; /** * Opaque handle to the service. */ struct GNUNET_CADET_Handle { /** * Message queue. */ struct GNUNET_MQ_Handle *mq; /** * Ports open. */ struct GNUNET_CONTAINER_MultiHashMap *ports; /** * Channels open. */ struct GNUNET_CONTAINER_MultiHashMap32 *channels; /** * child of the next channel to create (to avoid reusing IDs often) */ struct GNUNET_CADET_ClientChannelNumber next_ccn; /** * Configuration given by the client, in case of reconnection */ const struct GNUNET_CONFIGURATION_Handle *cfg; /** * Task for trying to reconnect. */ struct GNUNET_SCHEDULER_Task *reconnect_task; /** * Callback for an info task (only one active at a time). */ union CadetInfoCB info_cb; /** * Info callback closure for @c info_cb. */ void *info_cls; /** * Time to the next reconnect in case one reconnect fails */ struct GNUNET_TIME_Relative reconnect_time; }; /** * Opaque handle to a channel. */ struct GNUNET_CADET_Channel { /** * Other end of the channel. */ struct GNUNET_PeerIdentity peer; /** * Handle to the cadet this channel belongs to */ struct GNUNET_CADET_Handle *cadet; /** * Channel's port, if incoming. */ struct GNUNET_CADET_Port *incoming_port; /** * Any data the caller wants to put in here, used for the * various callbacks (@e disconnects, @e window_changes, handlers). */ void *ctx; /** * Message Queue for the channel (which we are implementing). */ struct GNUNET_MQ_Handle *mq; /** * Task to allow mq to send more traffic. */ struct GNUNET_SCHEDULER_Task *mq_cont; /** * Pending envelope with a message to be transmitted to the * service as soon as we are allowed to. Should only be * non-NULL if @e allow_send is 0. */ struct GNUNET_MQ_Envelope *pending_env; /** * Window change handler. */ GNUNET_CADET_WindowSizeEventHandler window_changes; /** * Disconnect handler. */ GNUNET_CADET_DisconnectEventHandler disconnects; /** * Local ID of the channel, #GNUNET_CADET_LOCAL_CHANNEL_ID_CLI bit is set if outbound. */ struct GNUNET_CADET_ClientChannelNumber ccn; /** * Channel options: reliability, etc. */ enum GNUNET_CADET_ChannelOption options; /** * How many messages are we allowed to send to the service right now? */ unsigned int allow_send; }; /** * Opaque handle to a port. */ struct GNUNET_CADET_Port { /** * Port "number" */ struct GNUNET_HashCode id; /** * Handle to the CADET session this port belongs to. */ struct GNUNET_CADET_Handle *cadet; /** * Closure for @a handler. */ void *cls; /** * Handler for incoming channels on this port */ GNUNET_CADET_ConnectEventHandler connects; /** * Closure for @ref connects */ void *connects_cls; /** * Window size change handler. */ GNUNET_CADET_WindowSizeEventHandler window_changes; /** * Handler called when an incoming channel is destroyed. */ GNUNET_CADET_DisconnectEventHandler disconnects; /** * Payload handlers for incoming channels. */ struct GNUNET_MQ_MessageHandler *handlers; }; /** * Find the Port struct for a hash. * * @param h CADET handle. * @param hash HashCode for the port number. * @return The port handle if known, NULL otherwise. */ static struct GNUNET_CADET_Port * find_port (const struct GNUNET_CADET_Handle *h, const struct GNUNET_HashCode *hash) { return GNUNET_CONTAINER_multihashmap_get (h->ports, hash); } /** * Get the channel handler for the channel specified by id from the given handle * * @param h Cadet handle * @param ccn ID of the wanted channel * @return handle to the required channel or NULL if not found */ static struct GNUNET_CADET_Channel * find_channel (struct GNUNET_CADET_Handle *h, struct GNUNET_CADET_ClientChannelNumber ccn) { return GNUNET_CONTAINER_multihashmap32_get (h->channels, ntohl (ccn.channel_of_client)); } /** * Create a new channel and insert it in the channel list of the cadet handle * * @param h Cadet handle * @param ccnp pointer to desired ccn of the channel, NULL to assign one automatically. * @return Handle to the created channel. */ static struct GNUNET_CADET_Channel * create_channel (struct GNUNET_CADET_Handle *h, const struct GNUNET_CADET_ClientChannelNumber *ccnp) { struct GNUNET_CADET_Channel *ch; struct GNUNET_CADET_ClientChannelNumber ccn; ch = GNUNET_new (struct GNUNET_CADET_Channel); ch->cadet = h; if (NULL == ccnp) { while (NULL != find_channel (h, h->next_ccn)) h->next_ccn.channel_of_client = htonl (GNUNET_CADET_LOCAL_CHANNEL_ID_CLI | (1 + ntohl (h->next_ccn.channel_of_client))); ccn = h->next_ccn; } else { ccn = *ccnp; } ch->ccn = ccn; GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_multihashmap32_put (h->channels, ntohl (ch->ccn.channel_of_client), ch, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)); return ch; } /** * Destroy the specified channel. * - Destroys all peers, calling the disconnect callback on each if needed * - Cancels all outgoing traffic for that channel, calling respective notifys * - Calls cleaner if channel was inbound * - Frees all memory used * * @param ch Pointer to the channel. * @param call_cleaner Whether to call the cleaner handler. */ static void destroy_channel (struct GNUNET_CADET_Channel *ch) { struct GNUNET_CADET_Handle *h = ch->cadet; LOG (GNUNET_ERROR_TYPE_DEBUG, "Destroying channel %X of %p\n", ch->ccn, h); GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multihashmap32_remove (h->channels, ntohl (ch->ccn.channel_of_client), ch)); if (NULL != ch->mq_cont) { GNUNET_SCHEDULER_cancel (ch->mq_cont); ch->mq_cont = NULL; } /* signal channel destruction */ if (NULL != ch->disconnects) ch->disconnects (ch->ctx, ch); if (NULL != ch->pending_env) GNUNET_MQ_discard (ch->pending_env); GNUNET_MQ_destroy (ch->mq); GNUNET_free (ch); } /** * Reconnect to the service, retransmit all infomation to try to restore the * original state. * * @param h handle to the cadet */ static void reconnect (struct GNUNET_CADET_Handle *h); /** * Reconnect callback: tries to reconnect again after a failer previous * reconnecttion * * @param cls closure (cadet handle) */ static void reconnect_cbk (void *cls) { struct GNUNET_CADET_Handle *h = cls; h->reconnect_task = NULL; reconnect (h); } /** * Function called during #reconnect() to destroy * all channels that are still open. * * @param cls the `struct GNUNET_CADET_Handle` * @param cid chanenl ID * @param value a `struct GNUNET_CADET_Channel` to destroy * @return #GNUNET_OK (continue to iterate) */ static int destroy_channel_on_reconnect_cb (void *cls, uint32_t cid, void *value) { /* struct GNUNET_CADET_Handle *handle = cls; */ struct GNUNET_CADET_Channel *ch = value; destroy_channel (ch); return GNUNET_OK; } /** * Reconnect to the service, retransmit all infomation to try to restore the * original state. * * @param h handle to the cadet * * @return #GNUNET_YES in case of sucess, #GNUNET_NO otherwise (service down...) */ static void schedule_reconnect (struct GNUNET_CADET_Handle *h) { if (NULL != h->reconnect_task) return; GNUNET_CONTAINER_multihashmap32_iterate (h->channels, &destroy_channel_on_reconnect_cb, h); h->reconnect_task = GNUNET_SCHEDULER_add_delayed (h->reconnect_time, &reconnect_cbk, h); h->reconnect_time = GNUNET_TIME_STD_BACKOFF (h->reconnect_time); } /** * Notify the application about a change in the window size (if needed). * * @param ch Channel to notify about. */ static void notify_window_size (struct GNUNET_CADET_Channel *ch) { if (NULL != ch->window_changes) ch->window_changes (ch->ctx, ch, /* FIXME: remove 'ch'? */ ch->allow_send); } /** * Transmit the next message from our queue. * * @param cls Closure (channel whose mq to activate). */ static void cadet_mq_send_now (void *cls) { struct GNUNET_CADET_Channel *ch = cls; struct GNUNET_MQ_Envelope *env = ch->pending_env; ch->mq_cont = NULL; if (0 == ch->allow_send) { /* how did we get here? */ GNUNET_break (0); return; } if (NULL == env) { /* how did we get here? */ GNUNET_break (0); return; } ch->allow_send--; ch->pending_env = NULL; GNUNET_MQ_send (ch->cadet->mq, env); GNUNET_MQ_impl_send_continue (ch->mq); } /** * Implement sending functionality of a message queue for * us sending messages to a peer. * * Encapsulates the payload message in a #GNUNET_CADET_LocalData message * in order to label the message with the channel ID and send the * encapsulated message to the service. * * @param mq the message queue * @param msg the message to send * @param impl_state state of the implementation */ static void cadet_mq_send_impl (struct GNUNET_MQ_Handle *mq, const struct GNUNET_MessageHeader *msg, void *impl_state) { struct GNUNET_CADET_Channel *ch = impl_state; struct GNUNET_CADET_Handle *h = ch->cadet; uint16_t msize; struct GNUNET_MQ_Envelope *env; struct GNUNET_CADET_LocalData *cadet_msg; if (NULL == h->mq) { /* We're currently reconnecting, pretend this worked */ GNUNET_MQ_impl_send_continue (mq); return; } /* check message size for sanity */ msize = ntohs (msg->size); if (msize > GNUNET_CONSTANTS_MAX_CADET_MESSAGE_SIZE) { GNUNET_break (0); GNUNET_MQ_impl_send_continue (mq); return; } env = GNUNET_MQ_msg_nested_mh (cadet_msg, GNUNET_MESSAGE_TYPE_CADET_LOCAL_DATA, msg); cadet_msg->ccn = ch->ccn; GNUNET_assert (NULL == ch->pending_env); ch->pending_env = env; if (0 < ch->allow_send) ch->mq_cont = GNUNET_SCHEDULER_add_now (&cadet_mq_send_now, ch); } /** * Handle destruction of a message queue. Implementations must not * free @a mq, but should take care of @a impl_state. * * @param mq the message queue to destroy * @param impl_state state of the implementation */ static void cadet_mq_destroy_impl (struct GNUNET_MQ_Handle *mq, void *impl_state) { struct GNUNET_CADET_Channel *ch = impl_state; GNUNET_assert (mq == ch->mq); ch->mq = NULL; } /** * We had an error processing a message we forwarded from a peer to * the CADET service. We should just complain about it but otherwise * continue processing. * * @param cls closure with our `struct GNUNET_CADET_Channel` * @param error error code */ static void cadet_mq_error_handler (void *cls, enum GNUNET_MQ_Error error) { struct GNUNET_CADET_Channel *ch = cls; GNUNET_break (0); if (GNUNET_MQ_ERROR_NO_MATCH == error) { /* Got a message we did not understand, still try to continue! */ GNUNET_CADET_receive_done (ch); } else { schedule_reconnect (ch->cadet); } } /** * Implementation function that cancels the currently sent message. * Should basically undo whatever #mq_send_impl() did. * * @param mq message queue * @param impl_state state specific to the implementation */ static void cadet_mq_cancel_impl (struct GNUNET_MQ_Handle *mq, void *impl_state) { struct GNUNET_CADET_Channel *ch = impl_state; GNUNET_assert (NULL != ch->pending_env); GNUNET_MQ_discard (ch->pending_env); ch->pending_env = NULL; if (NULL != ch->mq_cont) { GNUNET_SCHEDULER_cancel (ch->mq_cont); ch->mq_cont = NULL; } } /** * Process the new channel notification and add it to the channels in the handle * * @param h The cadet handle * @param msg A message with the details of the new incoming channel */ static void handle_channel_created (void *cls, const struct GNUNET_CADET_LocalChannelCreateMessage *msg) { struct GNUNET_CADET_Handle *h = cls; struct GNUNET_CADET_Channel *ch; struct GNUNET_CADET_Port *port; const struct GNUNET_HashCode *port_number; struct GNUNET_CADET_ClientChannelNumber ccn; ccn = msg->ccn; port_number = &msg->port; if (ntohl (ccn.channel_of_client) >= GNUNET_CADET_LOCAL_CHANNEL_ID_CLI) { GNUNET_break (0); return; } port = find_port (h, port_number); if (NULL == port) { /* We could have closed the port but the service didn't know about it yet * This is not an error. */ struct GNUNET_CADET_LocalChannelDestroyMessage *d_msg; struct GNUNET_MQ_Envelope *env; LOG (GNUNET_ERROR_TYPE_DEBUG, "No handler for incoming channel %X (on port %s, recently closed?)\n", ntohl (ccn.channel_of_client), GNUNET_h2s (port_number)); env = GNUNET_MQ_msg (d_msg, GNUNET_MESSAGE_TYPE_CADET_LOCAL_CHANNEL_DESTROY); d_msg->ccn = msg->ccn; GNUNET_MQ_send (h->mq, env); return; } ch = create_channel (h, &ccn); ch->peer = msg->peer; ch->cadet = h; ch->incoming_port = port; ch->options = ntohl (msg->opt); LOG (GNUNET_ERROR_TYPE_DEBUG, "Creating incoming channel %X [%s] %p\n", ntohl (ccn.channel_of_client), GNUNET_h2s (port_number), ch); GNUNET_assert (NULL != port->connects); ch->window_changes = port->window_changes; ch->disconnects = port->disconnects; ch->mq = GNUNET_MQ_queue_for_callbacks (&cadet_mq_send_impl, &cadet_mq_destroy_impl, &cadet_mq_cancel_impl, ch, port->handlers, &cadet_mq_error_handler, ch); ch->ctx = port->connects (port->cls, ch, &msg->peer); GNUNET_MQ_set_handlers_closure (ch->mq, ch->ctx); } /** * Process the channel destroy notification and free associated resources * * @param h The cadet handle * @param msg A message with the details of the channel being destroyed */ static void handle_channel_destroy (void *cls, const struct GNUNET_CADET_LocalChannelDestroyMessage *msg) { struct GNUNET_CADET_Handle *h = cls; struct GNUNET_CADET_Channel *ch; ch = find_channel (h, msg->ccn); if (NULL == ch) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Received channel destroy for unknown channel %X from CADET service (recently close?)\n", ntohl (msg->ccn.channel_of_client)); return; } LOG (GNUNET_ERROR_TYPE_DEBUG, "Received channel destroy for channel %X from CADET service\n", ntohl (msg->ccn.channel_of_client)); destroy_channel (ch); } /** * Check that message received from CADET service is well-formed. * * @param cls the `struct GNUNET_CADET_Handle` * @param message the message we got * @return #GNUNET_OK if the message is well-formed, * #GNUNET_SYSERR otherwise */ static int check_local_data (void *cls, const struct GNUNET_CADET_LocalData *message) { uint16_t size; size = ntohs (message->header.size); if (sizeof (*message) + sizeof (struct GNUNET_MessageHeader) > size) { GNUNET_break (0); return GNUNET_SYSERR; } return GNUNET_OK; } /** * Process the incoming data packets, call appropriate handlers. * * @param h The cadet handle * @param message A message encapsulating the data */ static void handle_local_data (void *cls, const struct GNUNET_CADET_LocalData *message) { struct GNUNET_CADET_Handle *h = cls; const struct GNUNET_MessageHeader *payload; struct GNUNET_CADET_Channel *ch; uint16_t type; int fwd; ch = find_channel (h, message->ccn); if (NULL == ch) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Unknown channel %X for incoming data (recently closed?)\n", ntohl (message->ccn.channel_of_client)); return; } payload = (const struct GNUNET_MessageHeader *) &message[1]; type = ntohs (payload->type); fwd = ntohl (ch->ccn.channel_of_client) <= GNUNET_CADET_LOCAL_CHANNEL_ID_CLI; LOG (GNUNET_ERROR_TYPE_DEBUG, "Got a %s data on channel %s [%X] of type %u\n", fwd ? "FWD" : "BWD", GNUNET_i2s (&ch->peer), ntohl (message->ccn.channel_of_client), type); GNUNET_MQ_inject_message (ch->mq, payload); } /** * Process a local ACK message, enabling the client to send * more data to the service. * * @param h Cadet handle. * @param message Message itself. */ static void handle_local_ack (void *cls, const struct GNUNET_CADET_LocalAck *message) { struct GNUNET_CADET_Handle *h = cls; struct GNUNET_CADET_Channel *ch; ch = find_channel (h, message->ccn); if (NULL == ch) { LOG (GNUNET_ERROR_TYPE_DEBUG, "ACK on unknown channel %X\n", ntohl (message->ccn.channel_of_client)); return; } ch->allow_send++; if (NULL == ch->pending_env) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Got an ACK on mq channel %X, allow send now %u!\n", ntohl (ch->ccn.channel_of_client), ch->allow_send); notify_window_size (ch); return; } if (NULL != ch->mq_cont) return; /* already working on it! */ LOG (GNUNET_ERROR_TYPE_DEBUG, "Got an ACK on mq channel %X, sending pending message!\n", ntohl (ch->ccn.channel_of_client)); ch->mq_cont = GNUNET_SCHEDULER_add_now (&cadet_mq_send_now, ch); } /** * 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, a `struct GNUNET_CORE_Handle *` * @param error error code */ static void handle_mq_error (void *cls, enum GNUNET_MQ_Error error) { struct GNUNET_CADET_Handle *h = cls; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "MQ ERROR: %u\n", error); GNUNET_MQ_destroy (h->mq); h->mq = NULL; reconnect (h); } /** * Process a local reply about info on all tunnels, pass info to the user. * * @param cls Closure (Cadet handle). * @param msg Message itself. */ static void handle_get_peers (void *cls, const struct GNUNET_CADET_LocalInfoPeer *msg) { struct GNUNET_CADET_Handle *h = cls; if (NULL == h->info_cb.peers_cb) return; h->info_cb.peers_cb (h->info_cls, &msg->destination, (int) ntohs (msg->tunnel), (unsigned int) ntohs (msg->paths), 0); } /** * Check that message received from CADET service is well-formed. * * @param cls the `struct GNUNET_CADET_Handle` * @param message the message we got * @return #GNUNET_OK if the message is well-formed, * #GNUNET_SYSERR otherwise */ static int check_get_peer (void *cls, const struct GNUNET_CADET_LocalInfoPeer *message) { size_t msize = sizeof (struct GNUNET_CADET_LocalInfoPeer); const struct GNUNET_PeerIdentity *paths_array; size_t esize; unsigned int epaths; unsigned int paths; unsigned int peers; esize = ntohs (message->header.size); if (esize < msize) { GNUNET_break (0); return GNUNET_SYSERR; } if (0 != ((esize - msize) % sizeof (struct GNUNET_PeerIdentity))) { GNUNET_break (0); return GNUNET_SYSERR; } peers = (esize - msize) / sizeof (struct GNUNET_PeerIdentity); epaths = ntohs (message->paths); paths_array = (const struct GNUNET_PeerIdentity *) &message[1]; paths = 0; for (unsigned int i = 0; i < peers; i++) if (0 == memcmp (&paths_array[i], &message->destination, sizeof (struct GNUNET_PeerIdentity))) paths++; if (paths != epaths) { GNUNET_break (0); return GNUNET_SYSERR; } return GNUNET_OK; } /** * Process a local peer info reply, pass info to the user. * * @param cls Closure (Cadet handle). * @param message Message itself. */ static void handle_get_peer (void *cls, const struct GNUNET_CADET_LocalInfoPeer *message) { struct GNUNET_CADET_Handle *h = cls; const struct GNUNET_PeerIdentity *paths_array; unsigned int paths; unsigned int path_length; int neighbor; unsigned int peers; if (NULL == h->info_cb.peer_cb) return; paths = ntohs (message->paths); paths_array = (const struct GNUNET_PeerIdentity *) &message[1]; peers = (ntohs (message->header.size) - sizeof (*message)) / sizeof (struct GNUNET_PeerIdentity); path_length = 0; neighbor = GNUNET_NO; for (unsigned int i = 0; i < peers; i++) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, " %s\n", GNUNET_i2s (&paths_array[i])); path_length++; if (0 == memcmp (&paths_array[i], &message->destination, sizeof (struct GNUNET_PeerIdentity))) { if (1 == path_length) neighbor = GNUNET_YES; path_length = 0; } } /* Call Callback with tunnel info. */ paths_array = (const struct GNUNET_PeerIdentity *) &message[1]; h->info_cb.peer_cb (h->info_cls, &message->destination, (int) ntohs (message->tunnel), neighbor, paths, paths_array); } /** * Process a local reply about info on all tunnels, pass info to the user. * * @param cls Closure (Cadet handle). * @param message Message itself. */ static void handle_get_tunnels (void *cls, const struct GNUNET_CADET_LocalInfoTunnel *msg) { struct GNUNET_CADET_Handle *h = cls; if (NULL == h->info_cb.tunnels_cb) return; h->info_cb.tunnels_cb (h->info_cls, &msg->destination, ntohl (msg->channels), ntohl (msg->connections), ntohs (msg->estate), ntohs (msg->cstate)); } /** * Check that message received from CADET service is well-formed. * * @param cls the `struct GNUNET_CADET_Handle` * @param msg the message we got * @return #GNUNET_OK if the message is well-formed, * #GNUNET_SYSERR otherwise */ static int check_get_tunnel (void *cls, const struct GNUNET_CADET_LocalInfoTunnel *msg) { unsigned int ch_n; unsigned int c_n; size_t esize; size_t msize; /* Verify message sanity */ msize = ntohs (msg->header.size); esize = sizeof (struct GNUNET_CADET_LocalInfoTunnel); if (esize > msize) { GNUNET_break (0); return GNUNET_SYSERR; } ch_n = ntohl (msg->channels); c_n = ntohl (msg->connections); esize += ch_n * sizeof (struct GNUNET_CADET_ChannelTunnelNumber); esize += c_n * sizeof (struct GNUNET_CADET_ConnectionTunnelIdentifier); if (msize != esize) { GNUNET_break_op (0); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "m:%u, e: %u (%u ch, %u conn)\n", (unsigned int) msize, (unsigned int) esize, ch_n, c_n); return GNUNET_SYSERR; } return GNUNET_OK; } /** * Process a local tunnel info reply, pass info to the user. * * @param cls Closure (Cadet handle). * @param msg Message itself. */ static void handle_get_tunnel (void *cls, const struct GNUNET_CADET_LocalInfoTunnel *msg) { struct GNUNET_CADET_Handle *h = cls; unsigned int ch_n; unsigned int c_n; const struct GNUNET_CADET_ConnectionTunnelIdentifier *conns; const struct GNUNET_CADET_ChannelTunnelNumber *chns; if (NULL == h->info_cb.tunnel_cb) return; ch_n = ntohl (msg->channels); c_n = ntohl (msg->connections); /* Call Callback with tunnel info. */ conns = (const struct GNUNET_CADET_ConnectionTunnelIdentifier *) &msg[1]; chns = (const struct GNUNET_CADET_ChannelTunnelNumber *) &conns[c_n]; h->info_cb.tunnel_cb (h->info_cls, &msg->destination, ch_n, c_n, chns, conns, ntohs (msg->estate), ntohs (msg->cstate)); } /** * Reconnect to the service, retransmit all infomation to try to restore the * original state. * * @param h handle to the cadet */ static void reconnect (struct GNUNET_CADET_Handle *h) { struct GNUNET_MQ_MessageHandler handlers[] = { GNUNET_MQ_hd_fixed_size (channel_created, GNUNET_MESSAGE_TYPE_CADET_LOCAL_CHANNEL_CREATE, struct GNUNET_CADET_LocalChannelCreateMessage, h), GNUNET_MQ_hd_fixed_size (channel_destroy, GNUNET_MESSAGE_TYPE_CADET_LOCAL_CHANNEL_DESTROY, struct GNUNET_CADET_LocalChannelDestroyMessage, h), GNUNET_MQ_hd_var_size (local_data, GNUNET_MESSAGE_TYPE_CADET_LOCAL_DATA, struct GNUNET_CADET_LocalData, h), GNUNET_MQ_hd_fixed_size (local_ack, GNUNET_MESSAGE_TYPE_CADET_LOCAL_ACK, struct GNUNET_CADET_LocalAck, h), GNUNET_MQ_hd_fixed_size (get_peers, GNUNET_MESSAGE_TYPE_CADET_LOCAL_INFO_PEERS, struct GNUNET_CADET_LocalInfoPeer, h), GNUNET_MQ_hd_var_size (get_peer, GNUNET_MESSAGE_TYPE_CADET_LOCAL_INFO_PEER, struct GNUNET_CADET_LocalInfoPeer, h), GNUNET_MQ_hd_fixed_size (get_tunnels, GNUNET_MESSAGE_TYPE_CADET_LOCAL_INFO_TUNNELS, struct GNUNET_CADET_LocalInfoTunnel, h), GNUNET_MQ_hd_var_size (get_tunnel, GNUNET_MESSAGE_TYPE_CADET_LOCAL_INFO_TUNNEL, struct GNUNET_CADET_LocalInfoTunnel, h), GNUNET_MQ_handler_end () }; h->mq = GNUNET_CLIENT_connect (h->cfg, "cadet", handlers, &handle_mq_error, h); if (NULL == h->mq) { schedule_reconnect (h); return; } h->reconnect_time = GNUNET_TIME_UNIT_MILLISECONDS; } /** * Function called during #GNUNET_CADET_disconnect() to destroy * all channels that are still open. * * @param cls the `struct GNUNET_CADET_Handle` * @param cid chanenl ID * @param value a `struct GNUNET_CADET_Channel` to destroy * @return #GNUNET_OK (continue to iterate) */ static int destroy_channel_cb (void *cls, uint32_t cid, void *value) { /* struct GNUNET_CADET_Handle *handle = cls; */ struct GNUNET_CADET_Channel *ch = value; if (ntohl (ch->ccn.channel_of_client) >= GNUNET_CADET_LOCAL_CHANNEL_ID_CLI) { GNUNET_break (0); LOG (GNUNET_ERROR_TYPE_DEBUG, "channel %X not destroyed\n", ntohl (ch->ccn.channel_of_client)); } destroy_channel (ch); return GNUNET_OK; } /** * Function called during #GNUNET_CADET_disconnect() to destroy * all ports that are still open. * * @param cls the `struct GNUNET_CADET_Handle` * @param id port ID * @param value a `struct GNUNET_CADET_Channel` to destroy * @return #GNUNET_OK (continue to iterate) */ static int destroy_port_cb (void *cls, const struct GNUNET_HashCode *id, void *value) { /* struct GNUNET_CADET_Handle *handle = cls; */ struct GNUNET_CADET_Port *port = value; /* This is a warning, the app should have cleanly closed all open ports */ GNUNET_break (0); GNUNET_CADET_close_port (port); return GNUNET_OK; } /** * Disconnect from the cadet service. All channels will be destroyed. All channel * disconnect callbacks will be called on any still connected peers, notifying * about their disconnection. The registered inbound channel cleaner will be * called should any inbound channels still exist. * * @param handle connection to cadet to disconnect */ void GNUNET_CADET_disconnect (struct GNUNET_CADET_Handle *handle) { GNUNET_CONTAINER_multihashmap_iterate (handle->ports, &destroy_port_cb, handle); GNUNET_CONTAINER_multihashmap_destroy (handle->ports); handle->ports = NULL; GNUNET_CONTAINER_multihashmap32_iterate (handle->channels, &destroy_channel_cb, handle); GNUNET_CONTAINER_multihashmap32_destroy (handle->channels); handle->channels = NULL; if (NULL != handle->mq) { GNUNET_MQ_destroy (handle->mq); handle->mq = NULL; } if (NULL != handle->reconnect_task) { GNUNET_SCHEDULER_cancel (handle->reconnect_task); handle->reconnect_task = NULL; } GNUNET_free (handle); } /** * Close a port opened with @a GNUNET_CADET_open_port(). * The @a new_channel callback will no longer be called. * * @param p Port handle. */ void GNUNET_CADET_close_port (struct GNUNET_CADET_Port *p) { struct GNUNET_CADET_PortMessage *msg; struct GNUNET_MQ_Envelope *env; env = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_CADET_LOCAL_PORT_CLOSE); msg->port = p->id; GNUNET_MQ_send (p->cadet->mq, env); GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove (p->cadet->ports, &p->id, p)); GNUNET_free_non_null (p->handlers); GNUNET_free (p); } /** * Destroy an existing channel. * * The existing end callback for the channel will be called immediately. * Any pending outgoing messages will be sent but no incoming messages will be * accepted and no data callbacks will be called. * * @param channel Channel handle, becomes invalid after this call. */ void GNUNET_CADET_channel_destroy (struct GNUNET_CADET_Channel *channel) { struct GNUNET_CADET_Handle *h = channel->cadet; struct GNUNET_CADET_LocalChannelDestroyMessage *msg; struct GNUNET_MQ_Envelope *env; if (NULL != h->mq) { env = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_CADET_LOCAL_CHANNEL_DESTROY); msg->ccn = channel->ccn; GNUNET_MQ_send (h->mq, env); } destroy_channel (channel); } /** * Get information about a channel. * * @param channel Channel handle. * @param option Query (GNUNET_CADET_OPTION_*). * @param ... dependant on option, currently not used * * @return Union with an answer to the query. */ const union GNUNET_CADET_ChannelInfo * GNUNET_CADET_channel_get_info (struct GNUNET_CADET_Channel *channel, enum GNUNET_CADET_ChannelOption option, ...) { static int bool_flag; switch (option) { case GNUNET_CADET_OPTION_NOBUFFER: case GNUNET_CADET_OPTION_RELIABLE: case GNUNET_CADET_OPTION_OUT_OF_ORDER: if (0 != (option & channel->options)) bool_flag = GNUNET_YES; else bool_flag = GNUNET_NO; return (const union GNUNET_CADET_ChannelInfo *) &bool_flag; break; case GNUNET_CADET_OPTION_PEER: return (const union GNUNET_CADET_ChannelInfo *) &channel->peer; break; default: GNUNET_break (0); return NULL; } } /** * Send an ack on the channel to confirm the processing of a message. * * @param ch Channel on which to send the ACK. */ void GNUNET_CADET_receive_done (struct GNUNET_CADET_Channel *channel) { struct GNUNET_CADET_LocalAck *msg; struct GNUNET_MQ_Envelope *env; env = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_CADET_LOCAL_ACK); LOG (GNUNET_ERROR_TYPE_DEBUG, "Sending ACK on channel %X\n", ntohl (channel->ccn.channel_of_client)); msg->ccn = channel->ccn; GNUNET_MQ_send (channel->cadet->mq, env); } /** * Send message of @a type to CADET service of @a h * * @param h handle to CADET service * @param type message type of trivial information request to send */ static void send_info_request (struct GNUNET_CADET_Handle *h, uint16_t type) { struct GNUNET_MessageHeader *msg; struct GNUNET_MQ_Envelope *env; env = GNUNET_MQ_msg (msg, type); GNUNET_MQ_send (h->mq, env); } /** * Request a debug dump on the service's STDERR. * * WARNING: unstable API, likely to change in the future! * * @param h cadet handle */ void GNUNET_CADET_request_dump (struct GNUNET_CADET_Handle *h) { send_info_request (h, GNUNET_MESSAGE_TYPE_CADET_LOCAL_INFO_DUMP); } /** * Request information about peers known to the running cadet service. * The callback will be called for every peer known to the service. * Only one info request (of any kind) can be active at once. * * WARNING: unstable API, likely to change in the future! * * @param h Handle to the cadet peer. * @param callback Function to call with the requested data. * @param callback_cls Closure for @c callback. * @return #GNUNET_OK / #GNUNET_SYSERR */ int GNUNET_CADET_get_peers (struct GNUNET_CADET_Handle *h, GNUNET_CADET_PeersCB callback, void *callback_cls) { if (NULL != h->info_cb.peers_cb) { GNUNET_break (0); return GNUNET_SYSERR; } send_info_request (h, GNUNET_MESSAGE_TYPE_CADET_LOCAL_INFO_PEERS); h->info_cb.peers_cb = callback; h->info_cls = callback_cls; return GNUNET_OK; } /** * Cancel a peer info request. The callback will not be called (anymore). * * WARNING: unstable API, likely to change in the future! * * @param h Cadet handle. * @return Closure given to GNUNET_CADET_get_peers(). */ void * GNUNET_CADET_get_peers_cancel (struct GNUNET_CADET_Handle *h) { void *cls = h->info_cls; h->info_cb.peers_cb = NULL; h->info_cls = NULL; return cls; } /** * Request information about a peer known to the running cadet peer. * The callback will be called for the tunnel once. * Only one info request (of any kind) can be active at once. * * WARNING: unstable API, likely to change in the future! * * @param h Handle to the cadet peer. * @param id Peer whose tunnel to examine. * @param callback Function to call with the requested data. * @param callback_cls Closure for @c callback. * @return #GNUNET_OK / #GNUNET_SYSERR */ int GNUNET_CADET_get_peer (struct GNUNET_CADET_Handle *h, const struct GNUNET_PeerIdentity *id, GNUNET_CADET_PeerCB callback, void *callback_cls) { struct GNUNET_CADET_LocalInfo *msg; struct GNUNET_MQ_Envelope *env; if (NULL != h->info_cb.peer_cb) { GNUNET_break (0); return GNUNET_SYSERR; } env = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_CADET_LOCAL_INFO_PEER); msg->peer = *id; GNUNET_MQ_send (h->mq, env); h->info_cb.peer_cb = callback; h->info_cls = callback_cls; return GNUNET_OK; } /** * Request information about tunnels of the running cadet peer. * The callback will be called for every tunnel of the service. * Only one info request (of any kind) can be active at once. * * WARNING: unstable API, likely to change in the future! * * @param h Handle to the cadet peer. * @param callback Function to call with the requested data. * @param callback_cls Closure for @c callback. * @return #GNUNET_OK / #GNUNET_SYSERR */ int GNUNET_CADET_get_tunnels (struct GNUNET_CADET_Handle *h, GNUNET_CADET_TunnelsCB callback, void *callback_cls) { if (NULL != h->info_cb.tunnels_cb) { GNUNET_break (0); return GNUNET_SYSERR; } send_info_request (h, GNUNET_MESSAGE_TYPE_CADET_LOCAL_INFO_TUNNELS); h->info_cb.tunnels_cb = callback; h->info_cls = callback_cls; return GNUNET_OK; } /** * Cancel a monitor request. The monitor callback will not be called. * * @param h Cadet handle. * @return Closure given to GNUNET_CADET_get_tunnels(). */ void * GNUNET_CADET_get_tunnels_cancel (struct GNUNET_CADET_Handle *h) { void *cls = h->info_cls; h->info_cb.tunnels_cb = NULL; h->info_cls = NULL; return cls; } /** * Request information about a tunnel of the running cadet peer. * The callback will be called for the tunnel once. * Only one info request (of any kind) can be active at once. * * WARNING: unstable API, likely to change in the future! * * @param h Handle to the cadet peer. * @param id Peer whose tunnel to examine. * @param callback Function to call with the requested data. * @param callback_cls Closure for @c callback. * @return #GNUNET_OK / #GNUNET_SYSERR */ int GNUNET_CADET_get_tunnel (struct GNUNET_CADET_Handle *h, const struct GNUNET_PeerIdentity *id, GNUNET_CADET_TunnelCB callback, void *callback_cls) { struct GNUNET_CADET_LocalInfo *msg; struct GNUNET_MQ_Envelope *env; if (NULL != h->info_cb.tunnel_cb) { GNUNET_break (0); return GNUNET_SYSERR; } env = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_CADET_LOCAL_INFO_TUNNEL); msg->peer = *id; GNUNET_MQ_send (h->mq, env); h->info_cb.tunnel_cb = callback; h->info_cls = callback_cls; return GNUNET_OK; } /** * Transitional function to convert an unsigned int port to a hash value. * WARNING: local static value returned, NOT reentrant! * WARNING: do not use this function for new code! * * @param port Numerical port (unsigned int format). * * @return A GNUNET_HashCode usable for the new CADET API. */ const struct GNUNET_HashCode * GC_u2h (uint32_t port) { static struct GNUNET_HashCode hash; GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "This is a transitional function, use proper crypto hashes as CADET ports\n"); GNUNET_CRYPTO_hash (&port, sizeof (port), &hash); return &hash; } /** * Connect to the MQ-based cadet service. * * @param cfg Configuration to use. * * @return Handle to the cadet service NULL on error. */ struct GNUNET_CADET_Handle * GNUNET_CADET_connecT (const struct GNUNET_CONFIGURATION_Handle *cfg) { struct GNUNET_CADET_Handle *h; LOG (GNUNET_ERROR_TYPE_DEBUG, "GNUNET_CADET_connecT()\n"); h = GNUNET_new (struct GNUNET_CADET_Handle); h->cfg = cfg; h->ports = GNUNET_CONTAINER_multihashmap_create (4, GNUNET_YES); h->channels = GNUNET_CONTAINER_multihashmap32_create (4); reconnect (h); if (NULL == h->mq) { GNUNET_break (0); GNUNET_CADET_disconnect (h); return NULL; } h->next_ccn.channel_of_client = htonl (GNUNET_CADET_LOCAL_CHANNEL_ID_CLI); h->reconnect_time = GNUNET_TIME_UNIT_MILLISECONDS; h->reconnect_task = NULL; return h; } /** * Open a port to receive incomming MQ-based channels. * * @param h CADET handle. * @param port Hash identifying the port. * @param connects Function called when an incoming channel is connected. * @param connects_cls Closure for the @a connects handler. * @param window_changes Function called when the transmit window size changes. * @param disconnects Function called when a channel is disconnected. * @param handlers Callbacks for messages we care about, NULL-terminated. * @return Port handle. */ struct GNUNET_CADET_Port * GNUNET_CADET_open_porT (struct GNUNET_CADET_Handle *h, const struct GNUNET_HashCode *port, GNUNET_CADET_ConnectEventHandler connects, void * connects_cls, GNUNET_CADET_WindowSizeEventHandler window_changes, GNUNET_CADET_DisconnectEventHandler disconnects, const struct GNUNET_MQ_MessageHandler *handlers) { struct GNUNET_CADET_PortMessage *msg; struct GNUNET_MQ_Envelope *env; struct GNUNET_CADET_Port *p; GNUNET_assert (NULL != connects); GNUNET_assert (NULL != disconnects); p = GNUNET_new (struct GNUNET_CADET_Port); p->cadet = h; p->id = *port; p->connects = connects; p->cls = connects_cls; p->window_changes = window_changes; p->disconnects = disconnects; p->handlers = GNUNET_MQ_copy_handlers (handlers); GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_multihashmap_put (h->ports, &p->id, p, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)); env = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_CADET_LOCAL_PORT_OPEN); msg->port = p->id; GNUNET_MQ_send (h->mq, env); return p; } /** * Create a new channel towards a remote peer. * * If the destination port is not open by any peer or the destination peer * does not accept the channel, #GNUNET_CADET_ChannelEndHandler will be called * for this channel. * * @param h CADET handle. * @param channel_cls Closure for the channel. It's given to: * - The disconnect handler @a disconnects * - Each message type callback in @a handlers * @param destination Peer identity the channel should go to. * @param port Identification of the destination port. * @param options CadetOption flag field, with all desired option bits set to 1. * @param window_changes Function called when the transmit window size changes. * @param disconnects Function called when the channel is disconnected. * @param handlers Callbacks for messages we care about, NULL-terminated. * @return Handle to the channel. */ struct GNUNET_CADET_Channel * GNUNET_CADET_channel_creatE (struct GNUNET_CADET_Handle *h, void *channel_cls, const struct GNUNET_PeerIdentity *destination, const struct GNUNET_HashCode *port, enum GNUNET_CADET_ChannelOption options, GNUNET_CADET_WindowSizeEventHandler window_changes, GNUNET_CADET_DisconnectEventHandler disconnects, const struct GNUNET_MQ_MessageHandler *handlers) { struct GNUNET_CADET_Channel *ch; struct GNUNET_CADET_LocalChannelCreateMessage *msg; struct GNUNET_MQ_Envelope *env; GNUNET_assert (NULL != disconnects); ch = create_channel (h, NULL); ch->ctx = channel_cls; ch->peer = *destination; ch->options = options; ch->window_changes = window_changes; ch->disconnects = disconnects; /* Create MQ for channel */ ch->mq = GNUNET_MQ_queue_for_callbacks (&cadet_mq_send_impl, &cadet_mq_destroy_impl, &cadet_mq_cancel_impl, ch, handlers, &cadet_mq_error_handler, ch); GNUNET_MQ_set_handlers_closure (ch->mq, channel_cls); /* Request channel creation to service */ env = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_CADET_LOCAL_CHANNEL_CREATE); msg->ccn = ch->ccn; msg->port = *port; msg->peer = *destination; msg->opt = htonl (options); GNUNET_MQ_send (h->mq, env); return ch; } /** * Obtain the message queue for a connected peer. * * @param channel The channel handle from which to get the MQ. * * @return NULL if @a channel is not yet connected. */ struct GNUNET_MQ_Handle * GNUNET_CADET_get_mq (const struct GNUNET_CADET_Channel *channel) { return channel->mq; } /* end of cadet_api.c */