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- /*
- 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 Affero General Public License as published
- by the Free Software Foundation, either version 3 of the License,
- or (at your option) any later version.
- GNUnet is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Affero General Public License for more details.
- You should have received a copy of the GNU Affero General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
- SPDX-License-Identifier: AGPL3.0-or-later
- */
- /**
- * @file 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__)
- /**
- * 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;
- /**
- * 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;
- /**
- * 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",
- htonl (ch->ccn.channel_of_client),
- 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);
- /**
- * Function called during #reconnect_cbk() to (re)open
- * 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 open
- * @return #GNUNET_OK (continue to iterate)
- */
- static int
- open_port_cb (void *cls, const struct GNUNET_HashCode *id, void *value)
- {
- struct GNUNET_CADET_Handle *h = cls;
- struct GNUNET_CADET_Port *port = value;
- struct GNUNET_CADET_PortMessage *msg;
- struct GNUNET_MQ_Envelope *env;
- (void) id;
- env = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_CADET_LOCAL_PORT_OPEN);
- msg->port = port->id;
- GNUNET_MQ_send (h->mq, env);
- return GNUNET_OK;
- }
- /**
- * 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;
- h->reconnect_time = GNUNET_TIME_STD_BACKOFF (h->reconnect_time);
- reconnect (h);
- GNUNET_CONTAINER_multihashmap_iterate (h->ports, &open_port_cb, h);
- }
- /**
- * 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_log (GNUNET_ERROR_TYPE_DEBUG,
- "Sending message on channel %s to CADET, new window size is %u\n",
- GNUNET_i2s (&ch->peer),
- ch->allow_send);
- 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 *orig_env;
- struct GNUNET_MQ_Envelope *env;
- struct GNUNET_CADET_LocalData *cadet_msg;
- enum GNUNET_MQ_PriorityPreferences pp;
- if (NULL == h->mq)
- {
- /* We're currently reconnecting, pretend this worked */
- GNUNET_MQ_impl_send_continue (mq);
- return;
- }
- orig_env = GNUNET_MQ_get_current_envelope (mq);
- pp = GNUNET_MQ_env_get_options (orig_env);
- /* 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;
- cadet_msg->pp = htonl ((uint32_t) pp);
- 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;
- if (GNUNET_MQ_ERROR_NO_MATCH == error)
- {
- /* Got a message we did not understand, still try to continue! */
- GNUNET_break_op (0);
- GNUNET_CADET_receive_done (ch);
- }
- else
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "MQ error in communication with CADET: %d\n",
- error);
- if (NULL != ch->disconnects)
- ch->disconnects (ch->ctx, ch);
- GNUNET_CADET_channel_destroy (ch);
- }
- }
- /**
- * 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;
- (void) mq;
- 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->incoming_port = port;
- 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;
- (void) cls;
- 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++;
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- "Got an ACK on mq channel %X (peer %s); new window size is %u!\n",
- ntohl (ch->ccn.channel_of_client),
- GNUNET_i2s (&ch->peer),
- 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! */
- ch->mq_cont = GNUNET_SCHEDULER_add_now (&cadet_mq_send_now, ch);
- }
- /**
- * 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;
- (void) cls;
- (void) cid;
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Destroying channel due to GNUNET_CADET_disconnect()\n");
- destroy_channel (ch);
- return GNUNET_OK;
- }
- /**
- * 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_CONTAINER_multihashmap32_iterate (h->channels, &destroy_channel_cb, h);
- GNUNET_MQ_destroy (h->mq);
- h->mq = NULL;
- GNUNET_assert (NULL == h->reconnect_task);
- h->reconnect_task =
- GNUNET_SCHEDULER_add_delayed (h->reconnect_time, &reconnect_cbk, h);
- }
- /**
- * 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_handler_end () };
- GNUNET_assert (NULL == h->mq);
- h->mq =
- GNUNET_CLIENT_connect (h->cfg, "cadet", handlers, &handle_mq_error, h);
- }
- /**
- * 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;
- (void) cls;
- (void) id;
- /* 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)
- {
- GNUNET_assert (
- GNUNET_YES ==
- GNUNET_CONTAINER_multihashmap_remove (p->cadet->ports, &p->id, p));
- if (NULL != p->cadet->mq)
- {
- 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_free_non_null (p->handlers);
- GNUNET_free (p);
- }
- /**
- * Destroy an existing channel.
- *
- * The existing end callback for the channel will NOT be called.
- * 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);
- }
- GNUNET_log (GNUNET_ERROR_TYPE_INFO,
- "Destroying channel due to GNUNET_CADET_channel_destroy()\n");
- channel->disconnects = NULL;
- 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_ChannelInfoOption option,
- ...)
- {
- switch (option)
- {
- case GNUNET_CADET_OPTION_PEER:
- return (const union GNUNET_CADET_ChannelInfo *) &channel->peer;
- 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);
- }
- /**
- * 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);
- return h;
- }
- /**
- * Function to return link to AGPL source upon request.
- *
- * @param cls closure with the identification of the client
- * @param msg AGPL request
- */
- static void
- return_agpl (void *cls, const struct GNUNET_MessageHeader *msg)
- {
- struct GNUNET_SERVICE_Client *client = cls;
- struct GNUNET_MQ_Handle *mq;
- struct GNUNET_MQ_Envelope *env;
- struct GNUNET_MessageHeader *res;
- size_t slen;
- const struct GNUNET_OS_ProjectData *pd = GNUNET_OS_project_data_get ();
- (void) msg;
- slen = strlen (pd->agpl_url) + 1;
- env = GNUNET_MQ_msg_extra (res, GNUNET_MESSAGE_TYPE_RESPONSE_AGPL, slen);
- memcpy (&res[1], GNUNET_AGPL_URL, slen);
- mq = GNUNET_SERVICE_client_get_mq (client);
- GNUNET_MQ_send (mq, env);
- GNUNET_SERVICE_client_continue (client);
- }
- /**
- * 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, NULL if port is in use
- */
- 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_Port *p;
- const struct GNUNET_OS_ProjectData *pd = GNUNET_OS_project_data_get ();
- GNUNET_assert (NULL != connects);
- GNUNET_assert (NULL != disconnects);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Listening to CADET port %s\n",
- GNUNET_h2s (port));
- p = GNUNET_new (struct GNUNET_CADET_Port);
- p->cadet = h;
- p->id = *port;
- if (GNUNET_OK != GNUNET_CONTAINER_multihashmap_put (
- h->ports,
- &p->id,
- p,
- GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
- {
- GNUNET_free (p);
- return NULL;
- }
- p->connects = connects;
- p->cls = connects_cls;
- p->window_changes = window_changes;
- p->disconnects = disconnects;
- p->handlers = (NULL == pd->agpl_url)
- ? GNUNET_MQ_copy_handlers (handlers)
- : GNUNET_MQ_copy_handlers2 (handlers, &return_agpl, NULL);
- GNUNET_assert (GNUNET_OK == open_port_cb (h, &p->id, p));
- return p;
- }
- /**
- * Create a new channel towards a remote peer.
- *
- * If the destination peer closes the channel after accepting it,
- * @a disconnects will be called for this channel (unless
- * #GNUNET_CADET_channel_destroy() was called on this end first).
- *
- * @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 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,
- 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);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Creating channel to peer %s at port %s\n",
- GNUNET_i2s (destination),
- GNUNET_h2s (port));
- ch = create_channel (h, NULL);
- ch->ctx = channel_cls;
- ch->peer = *destination;
- 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;
- 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 */
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