/* This file is part of GNUnet. Copyright (C) 2009-2014 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 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 include/gnunet_transport_service.h * @brief low-level P2P IO * @author Christian Grothoff */ #ifndef GNUNET_TRANSPORT_SERVICE_H #define GNUNET_TRANSPORT_SERVICE_H #ifdef __cplusplus extern "C" { #if 0 /* keep Emacsens' auto-indent happy */ } #endif #endif #include "gnunet_util_lib.h" #include "gnunet_ats_service.h" /** * Version number of the transport API. */ #define GNUNET_TRANSPORT_VERSION 0x00000002 /** * Function called by the transport for each received message. * * @param cls closure * @param peer (claimed) identity of the other peer * @param message the message */ typedef void (*GNUNET_TRANSPORT_ReceiveCallback) (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_MessageHeader *message); /** * Opaque handle to the service. */ struct GNUNET_TRANSPORT_Handle; /** * Function called to notify transport users that another * peer connected to us. * * @param cls closure * @param peer the peer that connected */ typedef void (*GNUNET_TRANSPORT_NotifyConnect) (void *cls, const struct GNUNET_PeerIdentity *peer); /** * Function called to notify transport users that another * peer disconnected from us. * * @param cls closure * @param peer the peer that disconnected */ typedef void (*GNUNET_TRANSPORT_NotifyDisconnect) (void *cls, const struct GNUNET_PeerIdentity *peer); /** * Connect to the transport service. Note that the connection may * complete (or fail) asynchronously. * * @param cfg configuration to use * @param self our own identity (API should check that it matches * the identity found by transport), or NULL (no check) * @param cls closure for the callbacks * @param rec receive function to call, or NULL * @param nc function to call on connect events, or NULL * @param nd function to call on disconnect events, or NULL * @return NULL on error */ struct GNUNET_TRANSPORT_Handle * GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_PeerIdentity *self, void *cls, GNUNET_TRANSPORT_ReceiveCallback rec, GNUNET_TRANSPORT_NotifyConnect nc, GNUNET_TRANSPORT_NotifyDisconnect nd); /** * Function called if we have "excess" bandwidth to a peer. * The notification will happen the first time we have excess * bandwidth, and then only again after the client has performed * some transmission to the peer. * * Excess bandwidth is defined as being allowed (by ATS) to send * more data, and us reaching the limit of the capacity build-up * (which, if we go past it, means we don't use available bandwidth). * See also the "max carry" in `struct GNUNET_BANDWIDTH_Tracker`. * * @param cls the closure * @param neighbour peer that we have excess bandwidth to */ typedef void (*GNUNET_TRANSPORT_NotifyExcessBandwidth)(void *cls, const struct GNUNET_PeerIdentity *neighbour); /** * Connect to the transport service. Note that the connection may * complete (or fail) asynchronously. * * @param cfg configuration to use * @param self our own identity (API should check that it matches * the identity found by transport), or NULL (no check) * @param cls closure for the callbacks * @param rec receive function to call, or NULL * @param nc function to call on connect events, or NULL * @param nd function to call on disconnect events, or NULL * @param neb function to call if we have excess bandwidth to a peer * @return NULL on error */ struct GNUNET_TRANSPORT_Handle * GNUNET_TRANSPORT_connect2 (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_PeerIdentity *self, void *cls, GNUNET_TRANSPORT_ReceiveCallback rec, GNUNET_TRANSPORT_NotifyConnect nc, GNUNET_TRANSPORT_NotifyDisconnect nd, GNUNET_TRANSPORT_NotifyExcessBandwidth neb); /** * Disconnect from the transport service. * * @param handle handle returned from connect */ void GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle); /* ************************* Connections *********************** */ /** * Opaque handle for a transmission-ready request. */ struct GNUNET_TRANSPORT_TryConnectHandle; /** * Function to call with result of the try connect request. * * @param cls closure * @param result #GNUNET_OK if message was transmitted to transport service * #GNUNET_SYSERR if message was not transmitted to transport service */ typedef void (*GNUNET_TRANSPORT_TryConnectCallback) (void *cls, int result); /** * Ask the transport service to establish a connection to * the given peer. * * @param handle connection to transport service * @param target who we should try to connect to * @param cb callback to be called when request was transmitted to transport * service * @param cb_cls closure for the callback @a cb * @return a `struct GNUNET_TRANSPORT_TryConnectHandle` handle or * NULL on failure (@a cb will not be called) */ struct GNUNET_TRANSPORT_TryConnectHandle * GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *target, GNUNET_TRANSPORT_TryConnectCallback cb, void *cb_cls); /** * Cancel the request to transport to try a connect * Callback will not be called * * @param tch handle to cancel */ void GNUNET_TRANSPORT_try_connect_cancel (struct GNUNET_TRANSPORT_TryConnectHandle *tch); /** * Opaque handle for a transmission-ready request. */ struct GNUNET_TRANSPORT_TryDisconnectHandle; /** * Function to call with result of the try connect request. * * @param cls closure * @param result #GNUNET_OK if message was transmitted to transport service * #GNUNET_SYSERR if message was not transmitted to transport service */ typedef void (*GNUNET_TRANSPORT_TryDisconnectCallback) (void *cls, int result); /** * Ask the transport service to disconnect from the given peer. * * @param handle connection to transport service * @param target who we should try to disconnect from * @param cb callback to be called when request was transmitted to transport * service * @param cb_cls closure for the callback @a cb * @return a `struct GNUNET_TRANSPORT_TryConnectHandle` handle or * NULL on failure (@a cb will not be called) */ struct GNUNET_TRANSPORT_TryDisconnectHandle * GNUNET_TRANSPORT_try_disconnect (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *target, GNUNET_TRANSPORT_TryDisconnectCallback cb, void *cb_cls); /** * Cancel the request to transport to disconnect. * Callback will not be called anymore. * * @param tdh handle for operation to cancel */ void GNUNET_TRANSPORT_try_disconnect_cancel (struct GNUNET_TRANSPORT_TryDisconnectHandle *tdh); /* ************************* Sending *************************** */ /** * Opaque handle for a transmission-ready request. */ struct GNUNET_TRANSPORT_TransmitHandle; /** * Function called to notify a client about the connection begin ready * to queue more data. @a buf will be NULL and @a size zero if the * connection was closed for writing in the meantime. * * @param cls closure * @param size number of bytes available in @a buf * @param buf where the callee should write the message * @return number of bytes written to @a buf */ typedef size_t (*GNUNET_TRANSPORT_TransmitReadyNotify) (void *cls, size_t size, void *buf); /** * Check if we could queue a message of the given size for * transmission. The transport service will take both its internal * buffers and bandwidth limits imposed by the other peer into * consideration when answering this query. * * @param handle connection to transport service * @param target who should receive the message * @param size how big is the message we want to transmit? * @param timeout after how long should we give up (and call * notify with buf NULL and size 0)? * @param notify function to call when we are ready to * send such a message * @param notify_cls closure for @a notify * @return NULL if someone else is already waiting to be notified * non-NULL if the notify callback was queued (can be used to cancel * using #GNUNET_TRANSPORT_notify_transmit_ready_cancel()) */ struct GNUNET_TRANSPORT_TransmitHandle * GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *target, size_t size, struct GNUNET_TIME_Relative timeout, GNUNET_TRANSPORT_TransmitReadyNotify notify, void *notify_cls); /** * Cancel the specified transmission-ready notification. * * @param th handle of the transmission notification request to cancel */ void GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct GNUNET_TRANSPORT_TransmitHandle *th); /** * Checks if a given peer is connected to us * * @param handle connection to transport service * @param peer the peer to check * @return #GNUNET_YES (connected) or #GNUNET_NO (disconnected) */ int GNUNET_TRANSPORT_check_peer_connected (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *peer); /* *********************** Metric manipulation ***************** */ /** * Set transport metrics for a peer and a direction * * @param handle transport handle * @param peer the peer to set the metric for * @param prop the performance metrics to set * @param delay_in inbound delay to introduce * @param delay_out outbound delay to introduce * * Note: Delay restrictions in receiving direction will be enforced * with one message delay. */ void GNUNET_TRANSPORT_set_traffic_metric (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_ATS_Properties *prop, struct GNUNET_TIME_Relative delay_in, struct GNUNET_TIME_Relative delay_out); /* *************************** HELLO *************************** */ /** * Function called whenever there is an update to the * HELLO of this peer. * * @param cls closure * @param hello our updated HELLO */ typedef void (*GNUNET_TRANSPORT_HelloUpdateCallback) (void *cls, const struct GNUNET_MessageHeader *hello); /** * Handle to cancel a #GNUNET_TRANSPORT_get_hello() operation. */ struct GNUNET_TRANSPORT_GetHelloHandle; /** * Obtain updates on changes to the HELLO message for this peer. The callback * given in this function is never called synchronously. * * @param handle connection to transport service * @param rec function to call with the HELLO * @param rec_cls closure for @a rec * @return handle to cancel the operation */ struct GNUNET_TRANSPORT_GetHelloHandle * GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle, GNUNET_TRANSPORT_HelloUpdateCallback rec, void *rec_cls); /** * Stop receiving updates about changes to our HELLO message. * * @param ghh handle to cancel */ void GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh); /** * Handle for a #GNUNET_TRANSPORT_offer_hello operation */ struct GNUNET_TRANSPORT_OfferHelloHandle; /** * 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 * @param cont continuation to call when HELLO has been sent, * tc reason #GNUNET_SCHEDULER_REASON_TIMEOUT for fail * tc reasong #GNUNET_SCHEDULER_REASON_READ_READY for success * @param cls closure for continuation * @return a GNUNET_TRANSPORT_OfferHelloHandle handle or NULL on failure, * in case of failure cont will not be called * */ struct GNUNET_TRANSPORT_OfferHelloHandle * GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_MessageHeader *hello, GNUNET_SCHEDULER_TaskCallback cont, void *cls); /** * Cancel the request to transport to offer the HELLO message * * @param ohh the `struct GNUNET_TRANSPORT_OfferHelloHandle` to cancel */ void GNUNET_TRANSPORT_offer_hello_cancel (struct GNUNET_TRANSPORT_OfferHelloHandle *ohh); /* *********************** Address to String ******************* */ /** * Handle to cancel a pending address lookup. */ struct GNUNET_TRANSPORT_AddressToStringContext; /** * Function to call with a textual representation of an address. This * function will be called several times with different possible * textual representations, and a last time with @a address being NULL * to signal the end of the iteration. Note that @a address NULL * always is the last call, regardless of the value in @a res. * * @param cls closure * @param address NULL on end of iteration, * otherwise 0-terminated printable UTF-8 string, * in particular an empty string if @a res is #GNUNET_NO * @param res result of the address to string conversion: * if #GNUNET_OK: conversion successful * if #GNUNET_NO: address was invalid (or not supported) * if #GNUNET_SYSERR: communication error (IPC error) */ typedef void (*GNUNET_TRANSPORT_AddressToStringCallback) (void *cls, const char *address, int res); /** * Convert a binary address into a human readable address. * * @param cfg configuration to use * @param address address to convert (binary format) * @param numeric should (IP) addresses be displayed in numeric form * (otherwise do reverse DNS lookup) * @param timeout how long is the lookup allowed to take at most * @param aluc function to call with the results * @param aluc_cls closure for @a aluc * @return handle to cancel the operation, NULL on error */ struct GNUNET_TRANSPORT_AddressToStringContext * GNUNET_TRANSPORT_address_to_string (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_HELLO_Address *address, int numeric, struct GNUNET_TIME_Relative timeout, GNUNET_TRANSPORT_AddressToStringCallback aluc, void *aluc_cls); /** * Cancel request for address conversion. * * @param pic the context handle */ void GNUNET_TRANSPORT_address_to_string_cancel (struct GNUNET_TRANSPORT_AddressToStringContext *pic); /* *********************** Monitoring ************************** */ /** * Possible state of a neighbour. Initially, we are #GNUNET_TRANSPORT_PS_NOT_CONNECTED. * * Then, there are two main paths. If we receive a SYN message, we give * the inbound address to ATS. After the check we ask ATS for a suggestion * (#GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS). If ATS makes a suggestion, we * send our SYN_ACK and go to #GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK. * If we receive a ACK, we go to #GNUNET_TRANSPORT_PS_CONNECTED * (and notify everyone about the new connection). If the operation times out, * we go to #GNUNET_TRANSPORT_PS_DISCONNECT. * * The other case is where we transmit a SYN message first. We * start with #GNUNET_TRANSPORT_PS_INIT_ATS. If we get an address, we send * the SYN message and go to state #GNUNET_TRANSPORT_PS_CONNECT_SENT. * Once we receive a SYN_ACK, we go to #GNUNET_TRANSPORT_PS_CONNECTED * (and notify everyone about the new connection and send * back a ACK). If the operation times out, we go to * #GNUNET_TRANSPORT_PS_DISCONNECT. * * If the session is in trouble (i.e. transport-level disconnect or * timeout), we go to #GNUNET_TRANSPORT_PS_RECONNECT_ATS where we ask ATS for a new * address (we don't notify anyone about the disconnect yet). Once we * have a new address, we enter #GNUNET_TRANSPORT_PS_RECONNECT_SENT and send a * SYN message. If we receive a * SYN_ACK, we go to #GNUNET_TRANSPORT_PS_CONNECTED and nobody noticed that we had * trouble; we also send a ACK at this time just in case. If * the operation times out, we go to #GNUNET_TRANSPORT_PS_DISCONNECT (and notify everyone * about the lost connection). * * If ATS decides to switch addresses while we have a normal * connection, we go to #GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_SYN_SENT * and send a SESSION_CONNECT. If we get a ACK back, we switch the * primary connection to the suggested alternative from ATS, go back * to #GNUNET_TRANSPORT_PS_CONNECTED and send a ACK to the other peer just to be * sure. If the operation times out * we go to #GNUNET_TRANSPORT_PS_CONNECTED (and notify ATS that the given alternative * address is "invalid"). * * Once a session is in #GNUNET_TRANSPORT_PS_DISCONNECT, it is cleaned up and then goes * to (#GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED). If we receive an explicit disconnect * request, we can go from any state to #GNUNET_TRANSPORT_PS_DISCONNECT, possibly after * generating disconnect notifications. * * Note that it is quite possible that while we are in any of these * states, we could receive a 'SYN' request from the other peer. * We then enter a 'weird' state where we pursue our own primary state * machine (as described above), but with the 'send_connect_ack' flag * set to 1. If our state machine allows us to send a 'SYN_ACK' * (because we have an acceptable address), we send the 'SYN_ACK' * and set the 'send_connect_ack' to 2. If we then receive a * 'ACK', we go to #GNUNET_TRANSPORT_PS_CONNECTED (and reset 'send_connect_ack' * to 0). * */ enum GNUNET_TRANSPORT_PeerState { /** * Fresh peer or completely disconnected */ GNUNET_TRANSPORT_PS_NOT_CONNECTED = 0, /** * Asked to initiate connection, trying to get address from ATS */ GNUNET_TRANSPORT_PS_INIT_ATS, /** * Sent SYN message to other peer, waiting for SYN_ACK */ GNUNET_TRANSPORT_PS_SYN_SENT, /** * Received a SYN, asking ATS about address suggestions. */ GNUNET_TRANSPORT_PS_SYN_RECV_ATS, /** * SYN request from other peer was SYN_ACK'ed, waiting for ACK. */ GNUNET_TRANSPORT_PS_SYN_RECV_ACK, /** * Got our SYN_ACK/ACK, connection is up. */ GNUNET_TRANSPORT_PS_CONNECTED, /** * Connection got into trouble, rest of the system still believes * it to be up, but we're getting a new address from ATS. */ GNUNET_TRANSPORT_PS_RECONNECT_ATS, /** * Sent SYN over new address (either by ATS telling us to switch * addresses or from RECONNECT_ATS); if this fails, we need to tell * the rest of the system about a disconnect. */ GNUNET_TRANSPORT_PS_RECONNECT_SENT, /** * We have some primary connection, but ATS suggested we switch * to some alternative; we now sent a SYN message for the * alternative session to the other peer and waiting for a * SYN_ACK to make this our primary connection. */ GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT, /** * Disconnect in progress (we're sending the DISCONNECT message to the * other peer; after that is finished, the state will be cleaned up). */ GNUNET_TRANSPORT_PS_DISCONNECT, /** * We're finished with the disconnect; and are cleaning up the state * now! We put the struct into this state when we are really in the * task that calls 'free' on it and are about to remove the record * from the map. We should never find a 'struct NeighbourMapEntry' * in this state in the map. Accessing a 'struct NeighbourMapEntry' * in this state virtually always means using memory that has been * freed (the exception being the cleanup code in #free_neighbour()). */ GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED }; /** * Convert a transport state to a human readable string. * * @param state the state */ const char * GNUNET_TRANSPORT_ps2s (enum GNUNET_TRANSPORT_PeerState state); /** * Check if a state is defined as connected * * @param state the state value * @return #GNUNET_YES or #GNUNET_NO */ int GNUNET_TRANSPORT_is_connected (enum GNUNET_TRANSPORT_PeerState state); /** * Handle for a #GNUNET_TRANSPORT_monitor_peers operation. */ struct GNUNET_TRANSPORT_PeerMonitoringContext; /** * Function to call with information about a peer * * If one_shot was set to #GNUNET_YES to iterate over all peers once, * a final call with NULL for peer and address will follow when done. * In this case state and timeout do not contain valid values. * * The #GNUNET_TRANSPORT_monitor_peers_cancel() call MUST not be called from * within this function! * * * @param cls closure * @param peer peer this update is about, * NULL if this is the final last callback for a iteration operation * @param address address, NULL if this is the final callback for iteration op * @param state current state this peer is in * @param state_timeout timeout for the current state of the peer */ typedef void (*GNUNET_TRANSPORT_PeerIterateCallback) (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_HELLO_Address *address, enum GNUNET_TRANSPORT_PeerState state, struct GNUNET_TIME_Absolute state_timeout); /** * Return information about a specific peer or all peers currently known to * transport service once or in monitoring mode. To obtain information about * a specific peer, a peer identity can be passed. To obtain information about * all peers currently known to transport service, NULL can be passed as peer * identity. * * For each peer, the callback is called with information about the address used * to communicate with this peer, the state this peer is currently in and the * the current timeout for this state. * * Upon completion, the #GNUNET_TRANSPORT_PeerIterateCallback is called one * more time with `NULL`. After this, the operation must no longer be * explicitly canceled. * * The #GNUNET_TRANSPORT_monitor_peers_cancel call MUST not be called in the * the peer_callback! * * @param cfg configuration to use * @param peer a specific peer identity to obtain information for, * NULL for all peers * @param one_shot #GNUNET_YES to return the current state and then end (with NULL+NULL), * #GNUNET_NO to monitor peers continuously * @param timeout how long is the lookup allowed to take at most * @param peer_callback function to call with the results * @param peer_callback_cls closure for @a peer_callback */ struct GNUNET_TRANSPORT_PeerMonitoringContext * GNUNET_TRANSPORT_monitor_peers (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_PeerIdentity *peer, int one_shot, struct GNUNET_TIME_Relative timeout, GNUNET_TRANSPORT_PeerIterateCallback peer_callback, void *peer_callback_cls); /** * Cancel request to monitor peers * * @param pic handle for the request to cancel */ void GNUNET_TRANSPORT_monitor_peers_cancel (struct GNUNET_TRANSPORT_PeerMonitoringContext *pic); /** * Handle for a #GNUNET_TRANSPORT_monitor_validation_entries() operation. */ struct GNUNET_TRANSPORT_ValidationMonitoringContext; /** * Current state of a validation process. * * FIXME: what state is used to indicate that a validation * was successful? If that is clarified/determined, "UGH" in * ~gnunet-peerinfo-gtk.c:1103 should be resolved. */ enum GNUNET_TRANSPORT_ValidationState { /** * Undefined state * * Used for final callback indicating operation done */ GNUNET_TRANSPORT_VS_NONE, /** * Fresh validation entry * * Entry was just created, no validation process was executed */ GNUNET_TRANSPORT_VS_NEW, /** * Updated validation entry * * This is an update for an existing validation entry */ GNUNET_TRANSPORT_VS_UPDATE, /** * Timeout for validation entry * * A timeout occured during the validation process */ GNUNET_TRANSPORT_VS_TIMEOUT, /** * Validation entry is removed * * The validation entry is getting removed due to a failed validation */ GNUNET_TRANSPORT_VS_REMOVE }; /** * Function to call with validation information about a peer * * This function is called by the transport validation monitoring api to * indicate a change to a validation entry. The information included represent * the current state of the validation entry, * * If the monitoring was called with `one_shot==GNUNET_YES`, a final callback * with `address==NULL` is executed. * * @param cls closure * @param address address this update is about, * NULL if this is the final last callback for a iteration operation * @param last_validation when was this address last validated * @param valid_until when does this address expire * @param next_validation time of the next validation operation * @param state state in the validation state machine */ typedef void (*GNUNET_TRANSPORT_ValidationIterateCallback) (void *cls, const struct GNUNET_HELLO_Address *address, struct GNUNET_TIME_Absolute last_validation, struct GNUNET_TIME_Absolute valid_until, struct GNUNET_TIME_Absolute next_validation, enum GNUNET_TRANSPORT_ValidationState state); /** * Convert validation state to human-readable string. * * @param state the state value * @return corresponding string */ const char * GNUNET_TRANSPORT_vs2s (enum GNUNET_TRANSPORT_ValidationState state); /** * Return information about pending address validation operations for a specific * or all peers * * @param cfg configuration to use * @param peer a specific peer identity to obtain validation entries for, * NULL for all peers * @param one_shot #GNUNET_YES to return all entries and then end (with NULL+NULL), * #GNUNET_NO to monitor validation entries continuously * @param timeout how long is the lookup allowed to take at most * @param validation_callback function to call with the results * @param validation_callback_cls closure for @a validation_callback */ struct GNUNET_TRANSPORT_ValidationMonitoringContext * GNUNET_TRANSPORT_monitor_validation_entries (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_PeerIdentity *peer, int one_shot, struct GNUNET_TIME_Relative timeout, GNUNET_TRANSPORT_ValidationIterateCallback validation_callback, void *validation_callback_cls); /** * Return information about all current pending validation operations * * @param vic handle for the request to cancel */ void GNUNET_TRANSPORT_monitor_validation_entries_cancel (struct GNUNET_TRANSPORT_ValidationMonitoringContext *vic); /* *********************** Blacklisting ************************ */ /** * Handle for blacklisting peers. */ struct GNUNET_TRANSPORT_Blacklist; /** * Function that decides if a connection is acceptable or not. * * @param cls closure * @param pid peer to approve or disapproave * @return #GNUNET_OK if the connection is allowed, #GNUNET_SYSERR if not */ typedef int (*GNUNET_TRANSPORT_BlacklistCallback) (void *cls, const struct GNUNET_PeerIdentity *pid); /** * Install a blacklist callback. The service will be queried for all * existing connections as well as any fresh connections to check if * they are permitted. If the blacklisting callback is unregistered, * all hosts that were denied in the past will automatically be * whitelisted again. Cancelling the blacklist handle is also the * only way to re-enable connections from peers that were previously * blacklisted. * * @param cfg configuration to use * @param cb callback to invoke to check if connections are allowed * @param cb_cls closure for @a cb * @return NULL on error, otherwise handle for cancellation */ struct GNUNET_TRANSPORT_Blacklist * GNUNET_TRANSPORT_blacklist (const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_TRANSPORT_BlacklistCallback cb, void *cb_cls); /** * Abort the blacklist. Note that this function is the only way for * removing a peer from the blacklist. * * @param br handle of the request that is to be cancelled */ void GNUNET_TRANSPORT_blacklist_cancel (struct GNUNET_TRANSPORT_Blacklist *br); /** * Handle for a plugin session state monitor. */ struct GNUNET_TRANSPORT_PluginMonitor; /** * Abstract representation of a plugin's session. * Corresponds to the `struct Session` within the TRANSPORT service. */ struct GNUNET_TRANSPORT_PluginSession; /** * Possible states of a session in a plugin. */ enum GNUNET_TRANSPORT_SessionState { /** * The session was created (first call for each session object). */ GNUNET_TRANSPORT_SS_INIT, /** * Initial session handshake is in progress. */ GNUNET_TRANSPORT_SS_HANDSHAKE, /** * Session is fully UP. */ GNUNET_TRANSPORT_SS_UP, /** * This is just an update about the session, * the state did not change. */ GNUNET_TRANSPORT_SS_UPDATE, /** * Session is being torn down and about to disappear. * Last call for each session object. */ GNUNET_TRANSPORT_SS_DONE }; /** * Information about a plugin's session. */ struct GNUNET_TRANSPORT_SessionInfo { /** * New state of the session. */ enum GNUNET_TRANSPORT_SessionState state; /** * #GNUNET_YES if this is an inbound connection, * #GNUNET_NO if this is an outbound connection, * #GNUNET_SYSERR if connections of this plugin * are so fundamentally bidirectional * that they have no 'initiator' */ int is_inbound; /** * Number of messages pending transmission for this session. */ uint32_t num_msg_pending; /** * Number of bytes pending transmission for this session. */ uint32_t num_bytes_pending; /** * Until when does this plugin refuse to receive to manage * staying within the inbound quota? ZERO if receive is * active. */ struct GNUNET_TIME_Absolute receive_delay; /** * At what time will this session timeout (unless activity * happens)? */ struct GNUNET_TIME_Absolute session_timeout; /** * Address used by the session. Can be NULL if none is available. */ const struct GNUNET_HELLO_Address *address; }; /** * Function called by the plugin with information about the * current sessions managed by the plugin (for monitoring). * * @param cls closure * @param session session handle this information is about, * NULL to indicate that we are "in sync" (initial * iteration complete) * @param session_ctx storage location where the application * can store data; will point to NULL on #GNUNET_TRANSPORT_SS_INIT, * and must be reset to NULL on #GNUNET_TRANSPORT_SS_DONE * @param info information about the state of the session, * NULL if @a session is also NULL and we are * merely signalling that the initial iteration is over; * NULL with @a session being non-NULL if the monitor * was being cancelled while sessions were active */ typedef void (*GNUNET_TRANSPORT_SessionMonitorCallback) (void *cls, struct GNUNET_TRANSPORT_PluginSession *session, void **session_ctx, const struct GNUNET_TRANSPORT_SessionInfo *info); /** * Install a plugin session state monitor callback. The callback * will be notified whenever the session changes. * * @param cfg configuration to use * @param cb callback to invoke on events * @param cb_cls closure for @a cb * @return NULL on error, otherwise handle for cancellation */ struct GNUNET_TRANSPORT_PluginMonitor * GNUNET_TRANSPORT_monitor_plugins (const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_TRANSPORT_SessionMonitorCallback cb, void *cb_cls); /** * Cancel monitoring the plugin session state. The callback will be * called once for each session that is up with the "info" argument * being NULL (this is just to enable client-side cleanup). * * @param pm handle of the request that is to be cancelled */ void GNUNET_TRANSPORT_monitor_plugins_cancel (struct GNUNET_TRANSPORT_PluginMonitor *pm); #if 0 /* keep Emacsens' auto-indent happy */ { #endif #ifdef __cplusplus } #endif /* ifndef GNUNET_TRANSPORT_SERVICE_H */ #endif /* end of gnunet_transport_service.h */