/* This file is part of GNUnet. Copyright (C) 2010-2015 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 . SPDX-License-Identifier: AGPL3.0-or-later */ /** * @file * Automatic transport selection and outbound bandwidth determination * * @author Christian Grothoff * @author Matthias Wachs * * @defgroup ats ATS service * Automatic Transport Selection and outbound bandwidth determination * * @see [Documentation](https://gnunet.org/ats-subsystem) * * @{ */ #ifndef GNUNET_ATS_SERVICE_H #define GNUNET_ATS_SERVICE_H #include "gnunet_constants.h" #include "gnunet_util_lib.h" #include "gnunet_hello_lib.h" /** * Default bandwidth assigned to a network : 64 KB/s */ #define GNUNET_ATS_DefaultBandwidth 65536 /** * Undefined value for an `enum GNUNET_ATS_Property` */ #define GNUNET_ATS_VALUE_UNDEFINED UINT32_MAX /** * String representation for GNUNET_ATS_VALUE_UNDEFINED */ #define GNUNET_ATS_VALUE_UNDEFINED_STR "undefined" /** * Maximum bandwidth assigned to a network : 4095 MB/s */ #define GNUNET_ATS_MaxBandwidth UINT32_MAX /** * Textual equivalent for GNUNET_ATS_MaxBandwidth */ #define GNUNET_ATS_MaxBandwidthString "unlimited" /** * ATS performance characteristics for an address. */ struct GNUNET_ATS_Properties { /** * Delay. Time between when the time packet is sent and the packet * arrives. FOREVER if we did not measure yet. */ struct GNUNET_TIME_Relative delay; /** * Actual traffic on this connection from this peer to the other peer. * Includes transport overhead. * * Unit: [bytes/second] */ uint32_t utilization_out; /** * Actual traffic on this connection from the other peer to this peer. * Includes transport overhead. * * Unit: [bytes/second] */ uint32_t utilization_in; /** * Distance on network layer (required for distance-vector routing) * in hops. Zero for direct connections (i.e. plain TCP/UDP). */ unsigned int distance; /** * Which network scope does the respective address belong to? * This property does not change. */ enum GNUNET_NetworkType scope; }; /** * ATS performance characteristics for an address in * network byte order (for IPC). */ struct GNUNET_ATS_PropertiesNBO { /** * Actual traffic on this connection from this peer to the other peer. * Includes transport overhead. * * Unit: [bytes/second] */ uint32_t utilization_out GNUNET_PACKED; /** * Actual traffic on this connection from the other peer to this peer. * Includes transport overhead. * * Unit: [bytes/second] */ uint32_t utilization_in GNUNET_PACKED; /** * Which network scope does the respective address belong to? * This property does not change. */ uint32_t scope GNUNET_PACKED; /** * Distance on network layer (required for distance-vector routing) * in hops. Zero for direct connections (i.e. plain TCP/UDP). */ uint32_t distance GNUNET_PACKED; /** * Delay. Time between when the time packet is sent and the packet * arrives. FOREVER if we did not measure yet. */ struct GNUNET_TIME_RelativeNBO delay; }; /* ********************* LAN Characterization library ************************ */ /* Note: these functions do not really communicate with the ATS service */ /** * Convert ATS properties from host to network byte order. * * @param nbo[OUT] value written * @param hbo value read */ void GNUNET_ATS_properties_hton (struct GNUNET_ATS_PropertiesNBO *nbo, const struct GNUNET_ATS_Properties *hbo); /** * Convert ATS properties from network to host byte order. * * @param hbo[OUT] value written * @param nbo value read */ void GNUNET_ATS_properties_ntoh (struct GNUNET_ATS_Properties *hbo, const struct GNUNET_ATS_PropertiesNBO *nbo); /* ********************Connection Suggestion API ***************************** */ /** * Handle to the ATS subsystem for making suggestions about * connections the peer would like to have. */ struct GNUNET_ATS_ConnectivityHandle; /** * Handle for address suggestion requests. */ struct GNUNET_ATS_ConnectivitySuggestHandle; /** * Initialize the ATS connectivity suggestion client handle. * * @param cfg configuration to use * @return ats connectivity handle, NULL on error */ struct GNUNET_ATS_ConnectivityHandle * GNUNET_ATS_connectivity_init (const struct GNUNET_CONFIGURATION_Handle *cfg); /** * Shutdown ATS connectivity suggestion client. * * @param ch handle to destroy */ void GNUNET_ATS_connectivity_done (struct GNUNET_ATS_ConnectivityHandle *ch); /** * We would like to establish a new connection with a peer. ATS * should suggest a good address to begin with. * * @param ch handle * @param peer identity of the peer we need an address for * @param strength how urgent is the need for such a suggestion * @return suggestion handle, NULL if request is already pending */ struct GNUNET_ATS_ConnectivitySuggestHandle * GNUNET_ATS_connectivity_suggest (struct GNUNET_ATS_ConnectivityHandle *ch, const struct GNUNET_PeerIdentity *peer, uint32_t strength); /** * We no longer care about being connected to a peer. * * @param sh handle */ void GNUNET_ATS_connectivity_suggest_cancel (struct GNUNET_ATS_ConnectivitySuggestHandle *sh); /* ******************************** Scheduling API ***************************** */ /** * Handle to the ATS subsystem for bandwidth/transport scheduling information. */ struct GNUNET_ATS_SchedulingHandle; /** * Opaque session handle, defined by plugins. Contents not known to ATS. */ struct GNUNET_ATS_Session; /** * Signature of a function called by ATS with the current bandwidth * and address preferences as determined by ATS. If our connection * to ATS dies and thus all suggestions become invalid, this function * is called ONCE with all arguments (except @a cls) being NULL/0. * * @param cls closure * @param peer for which we suggest an address, NULL if ATS connection died * @param address suggested address (including peer identity of the peer), * may be NULL to signal disconnect from peer * @param session session to use, NULL to establish a new outgoing session * @param bandwidth_out assigned outbound bandwidth for the connection, * 0 to signal disconnect * @param bandwidth_in assigned inbound bandwidth for the connection, * 0 to signal disconnect */ typedef void (*GNUNET_ATS_AddressSuggestionCallback) (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_HELLO_Address *address, struct GNUNET_ATS_Session *session, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in); /** * Initialize the ATS scheduling subsystem. * * @param cfg configuration to use * @param suggest_cb notification to call whenever the suggestation changed * @param suggest_cb_cls closure for @a suggest_cb * @return ats context */ struct GNUNET_ATS_SchedulingHandle * GNUNET_ATS_scheduling_init (const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_ATS_AddressSuggestionCallback suggest_cb, void *suggest_cb_cls); /** * Client is done with ATS scheduling, release resources. * * @param sh handle to release */ void GNUNET_ATS_scheduling_done (struct GNUNET_ATS_SchedulingHandle *sh); /** * Handle used within ATS to track an address. */ struct GNUNET_ATS_AddressRecord; /** * We have a new address ATS should know. Addresses have to be added with this * function before they can be: updated, set in use and destroyed * * @param sh handle * @param address the address * @param session session handle (if available, i.e. for incoming connections) * @param prop performance data for the address * @return handle to the address representation inside ATS, NULL * on error (i.e. ATS knows this exact address already, or * address is invalid) */ struct GNUNET_ATS_AddressRecord * GNUNET_ATS_address_add (struct GNUNET_ATS_SchedulingHandle *sh, const struct GNUNET_HELLO_Address *address, struct GNUNET_ATS_Session *session, const struct GNUNET_ATS_Properties *prop); /** * An address was used to initiate a session. * * @param ar address record to update information for * @param session session handle */ void GNUNET_ATS_address_add_session (struct GNUNET_ATS_AddressRecord *ar, struct GNUNET_ATS_Session *session); /** * A @a session was destroyed, disassociate it from the given address * record. If this was an incoming addess, destroys the address as * well. * * @param ar address record to update information for * @param session session handle * @return #GNUNET_YES if the @a ar was destroyed because * it was an incoming address, * #GNUNET_NO if the @ar was kept because we can * use it still to establish a new session */ int GNUNET_ATS_address_del_session (struct GNUNET_ATS_AddressRecord *ar, struct GNUNET_ATS_Session *session); /** * We have updated performance statistics for a given address. Note * that this function can be called for addresses that are currently * in use as well as addresses that are valid but not actively in use. * Furthermore, the peer may not even be connected to us right now (@a * session value of NULL used to signal disconnect, or somehow we * otherwise got updated on @a ats information). Based on the * information provided, ATS may update bandwidth assignments and * suggest to switch addresses. * * @param ar address record to update information for * @param prop performance data for the address */ void GNUNET_ATS_address_update (struct GNUNET_ATS_AddressRecord *ar, const struct GNUNET_ATS_Properties *prop); /** * An address got destroyed, stop using it as a valid address. * * @param ar address record to destroy, it's validation has * expired and ATS may no longer use it */ void GNUNET_ATS_address_destroy (struct GNUNET_ATS_AddressRecord *ar); /* ******************************** Performance API ***************************** */ /** * ATS Handle to obtain and/or modify performance information. */ struct GNUNET_ATS_PerformanceHandle; /** * Signature of a function that is called with QoS information about an address. * * @param cls closure * @param address the address, NULL if ATS service was disconnected or * when the iteration is completed in the case of * #GNUNET_ATS_performance_list_addresses() * @param address_active #GNUNET_YES if this address is actively used * to maintain a connection to a peer; * #GNUNET_NO if the address is not actively used; * #GNUNET_SYSERR if this address is no longer available for ATS * @param bandwidth_out assigned outbound bandwidth for the connection * @param bandwidth_in assigned inbound bandwidth for the connection * @param prop performance data for the address */ typedef void (*GNUNET_ATS_AddressInformationCallback) (void *cls, const struct GNUNET_HELLO_Address *address, int address_active, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in, const struct GNUNET_ATS_Properties *prop); /** * Handle for an address listing operation */ struct GNUNET_ATS_AddressListHandle; /** * Get handle to access performance API of the ATS subsystem. * * @param cfg configuration to use * @param addr_info_cb callback called when performance characteristics for * an address change * @param addr_info_cb_cls closure for @a addr_info_cb * @return ats performance context */ struct GNUNET_ATS_PerformanceHandle * GNUNET_ATS_performance_init (const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_ATS_AddressInformationCallback addr_info_cb, void *addr_info_cb_cls); /** * Get information about addresses known to the ATS subsystem. * * @param ph the performance handle to use * @param peer peer idm can be NULL for all peers * @param all #GNUNET_YES to get information about all addresses or #GNUNET_NO to * get only address currently used * @param infocb callback to call with the addresses, * will callback with address == NULL when done * @param infocb_cls closure for @a infocb * @return handle to abort the operation */ struct GNUNET_ATS_AddressListHandle * GNUNET_ATS_performance_list_addresses (struct GNUNET_ATS_PerformanceHandle *ph, const struct GNUNET_PeerIdentity *peer, int all, GNUNET_ATS_AddressInformationCallback infocb, void *infocb_cls); /** * Cancel a pending address listing operation * * @param alh the `struct GNUNET_ATS_AddressListHandle` handle to cancel */ void GNUNET_ATS_performance_list_addresses_cancel (struct GNUNET_ATS_AddressListHandle *alh); /** * Client is done using the ATS performance subsystem, release resources. * * @param ph handle */ void GNUNET_ATS_performance_done (struct GNUNET_ATS_PerformanceHandle *ph); /** * Function called with reservation result. * * @param cls closure * @param peer identifies the peer * @param amount set to the amount that was actually reserved or unreserved; * either the full requested amount or zero (no partial reservations) * @param res_delay if the reservation could not be satisfied (amount was 0), how * long should the client wait until re-trying? */ typedef void (*GNUNET_ATS_ReservationCallback) (void *cls, const struct GNUNET_PeerIdentity *peer, int32_t amount, struct GNUNET_TIME_Relative res_delay); /** * Context that can be used to cancel a peer information request. */ struct GNUNET_ATS_ReservationContext; /** * Reserve inbound bandwidth from the given peer. ATS will look at * the current amount of traffic we receive from the peer and ensure * that the peer could add 'amount' of data to its stream. * * @param ph performance handle * @param peer identifies the peer * @param amount reserve N bytes for receiving, negative * amounts can be used to undo a (recent) reservation; * @param rcb function to call with the resulting reservation information * @param rcb_cls closure for @a rcb * @return NULL on error * @deprecated will be replaced soon */ struct GNUNET_ATS_ReservationContext * GNUNET_ATS_reserve_bandwidth (struct GNUNET_ATS_PerformanceHandle *ph, const struct GNUNET_PeerIdentity *peer, int32_t amount, GNUNET_ATS_ReservationCallback rcb, void *rcb_cls); /** * Cancel request for reserving bandwidth. * * @param rc context returned by the original GNUNET_ATS_reserve_bandwidth call */ void GNUNET_ATS_reserve_bandwidth_cancel (struct GNUNET_ATS_ReservationContext *rc); /** * ATS preference types as array initializer */ #define GNUNET_ATS_PreferenceType {GNUNET_ATS_PREFERENCE_BANDWIDTH, GNUNET_ATS_PREFERENCE_LATENCY, GNUNET_ATS_PREFERENCE_END} /** * ATS preference types as string array initializer */ #define GNUNET_ATS_PreferenceTypeString {"BANDWIDTH", "LATENCY", "END" } /** * Enum defining all known preference categories. */ enum GNUNET_ATS_PreferenceKind { /** * Change the peer's bandwidth value (value per byte of bandwidth in * the goal function) to the given amount. The argument is followed * by a double value giving the desired value (can be negative). * Preference changes are forgotten if peers disconnect. */ GNUNET_ATS_PREFERENCE_BANDWIDTH = 0, /** * Change the peer's latency value to the given amount. The * argument is followed by a double value giving the desired value * (can be negative). The absolute score in the goal function is * the inverse of the latency in microseconds (minimum: 1 * microsecond) multiplied by the latency preferences. */ GNUNET_ATS_PREFERENCE_LATENCY = 1, /** * End of preference list. */ GNUNET_ATS_PREFERENCE_END = 2 }; /** * Convert a GNUNET_ATS_PreferenceType to a string * * @param type the preference type * @return a string or NULL if invalid */ const char * GNUNET_ATS_print_preference_type (enum GNUNET_ATS_PreferenceKind type); /** * Change preferences for the given peer. Preference changes are forgotten if peers * disconnect. * * @param ph performance handle @param peer identifies the peer * @param ... #GNUNET_ATS_PREFERENCE_END-terminated specification of the * desired changes */ void GNUNET_ATS_performance_change_preference (struct GNUNET_ATS_PerformanceHandle *ph, const struct GNUNET_PeerIdentity *peer, ...); /** * Application feedback on how good preference requirements are fulfilled * for the preferences included in the given time scope [now - scope .. now] * * An application notifies ATS if (and only if) it has feedback information * for specific properties. This values are valid until the feedback scores are * updated by the application. * * If the application has no feedback for this preference kind the application * will not explicitly call for this property and will not include it in this * function call. * * @param ph performance handle * @param scope the time interval this valid for: [now - scope .. now] * @param peer identifies the peer * @param ... #GNUNET_ATS_PREFERENCE_END-terminated specification of the desired changes */ void GNUNET_ATS_performance_give_feedback (struct GNUNET_ATS_PerformanceHandle *ph, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_TIME_Relative scope, ...); #endif /** @} */ /* end of group */ /* end of file gnunet-service-transport_ats.h */