/* This file is part of GNUnet. (C) 2009, 2010, 2011 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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 0x00000000 /** * Function called by the transport for each received message. * * @param cls closure * @param peer (claimed) identity of the other peer * @param message the message * @param ats performance data * @param ats_count number of entries in ats */ typedef void (*GNUNET_TRANSPORT_ReceiveCallback) (void *cls, const struct GNUNET_PeerIdentity * peer, const struct GNUNET_MessageHeader * message, const struct GNUNET_ATS_Information * ats, uint32_t ats_count); /** * 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 * @param ats performance data * @param ats_count number of entries in ats (excluding 0-termination) */ typedef void (*GNUNET_TRANSPORT_NotifyConnect) (void *cls, const struct GNUNET_PeerIdentity * peer, const struct GNUNET_ATS_Information * ats, uint32_t ats_count); /** * 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); /** * 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 NULL to signal the end * of the iteration. * * @param cls closure * @param address NULL on error or end of iteration, * otherwise 0-terminated printable UTF-8 string */ typedef void (*GNUNET_TRANSPORT_AddressToStringCallback) (void *cls, const char *address); /** * Function to call with a binary format of an address * * @param cls closure * @param peer peer this update is about (never NULL) * @param address address, NULL for disconnect notification in monitor mode */ typedef void (*GNUNET_TRANSPORT_PeerIterateCallback) (void *cls, const struct GNUNET_PeerIdentity * peer, const struct GNUNET_HELLO_Address * address); /** * Connect to the transport service. Note that the connection may * complete (or fail) asynchronously. * * @param cfg configuration to use * @param self our own identity (API should check that it matches * the identity found by transport), or NULL (no check) * @param cls closure for the callbacks * @param rec receive function to call * @param nc function to call on connect events * @param nd function to call on disconnect events * @return NULL on error */ struct GNUNET_TRANSPORT_Handle * GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_PeerIdentity *self, void *cls, GNUNET_TRANSPORT_ReceiveCallback rec, GNUNET_TRANSPORT_NotifyConnect nc, GNUNET_TRANSPORT_NotifyDisconnect nd); /** * Disconnect from the transport service. * * @param handle handle returned from connect */ void GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle); /** * 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 */ void GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *target); /** * Opaque handle for a transmission-ready request. */ struct GNUNET_TRANSPORT_TransmitHandle; /** * Check if we could queue a message of the given size for * transmission. The transport service will take both its internal * buffers and bandwidth limits imposed by the other peer into * consideration when answering this query. * * @param handle connection to transport service * @param target who should receive the message * @param size how big is the message we want to transmit? * @param priority how important is the message? @deprecated - remove? * @param timeout after how long should we give up (and call * notify with buf NULL and size 0)? * @param notify function to call when we are ready to * send such a message * @param notify_cls closure for notify * @return NULL if someone else is already waiting to be notified * non-NULL if the notify callback was queued (can be used to cancel * using GNUNET_TRANSPORT_notify_transmit_ready_cancel) */ struct GNUNET_TRANSPORT_TransmitHandle * GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_PeerIdentity *target, size_t size, uint32_t priority, struct GNUNET_TIME_Relative timeout, GNUNET_CONNECTION_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); /** * 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. * * @param handle connection to transport service * @param rec function to call with the HELLO * @param rec_cls closure for 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 returned from 'GNUNET_TRANSPORT_get_hello') */ void GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh); /** * 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 * @param cls closure for continuation */ void GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle, const struct GNUNET_MessageHeader *hello, GNUNET_SCHEDULER_Task cont, void *cls); /** * Handle to cancel a pending address lookup. */ struct GNUNET_TRANSPORT_AddressToStringContext; /** * Convert a binary address into a human readable address. * * @param cfg configuration to use * @param address address to convert (binary format) * @param addressLen number of bytes in address * @param numeric should (IP) addresses be displayed in numeric form * (otherwise do reverse DNS lookup) * @param nameTrans name of the transport to which the address belongs * @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 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 alc handle for the request to cancel */ void GNUNET_TRANSPORT_address_to_string_cancel (struct GNUNET_TRANSPORT_AddressToStringContext *alc); /** * Return all the known addresses for a specific peer or all peers. * Returns continously all address if one_shot is set to GNUNET_NO * * CHANGE: Returns the address(es) that we are currently using for this * peer. Upon completion, the 'AddressLookUpCallback' is called one more * time with 'NULL' for the address and the peer. After this, the operation must no * longer be explicitly cancelled. * * @param cfg configuration to use * @param peer peer identity to look up the addresses of, CHANGE: allow NULL for all (connected) peers * @param one_shot GNUNET_YES to return the current state and then end (with NULL+NULL), * GNUNET_NO to monitor the set of addresses used (continuously, must be explicitly canceled, NOT implemented yet!) * @param timeout how long is the lookup allowed to take at most * @param peer_address_callback function to call with the results * @param peer_address_callback_cls closure for peer_address_callback */ struct GNUNET_TRANSPORT_PeerIterateContext * GNUNET_TRANSPORT_peer_get_active_addresses (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_PeerIdentity *peer, int one_shot, struct GNUNET_TIME_Relative timeout, GNUNET_TRANSPORT_PeerIterateCallback peer_address_callback, void *peer_address_callback_cls); /** * Cancel request for peer lookup. * * @param alc handle for the request to cancel */ void GNUNET_TRANSPORT_peer_get_active_addresses_cancel (struct GNUNET_TRANSPORT_PeerIterateContext *alc); /** * 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 */ 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 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); #if 0 /* keep Emacsens' auto-indent happy */ { #endif #ifdef __cplusplus } #endif /* ifndef GNUNET_TRANSPORT_SERVICE_H */ #endif /* end of gnunet_transport_service.h */