/*
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*/
/**
* @file ats/gnunet-service-ats_addresses.h
* @brief ats service address management
* @author Matthias Wachs
* @author Christian Grothoff
*/
#ifndef GNUNET_SERVICE_ATS_ADDRESSES_H
#define GNUNET_SERVICE_ATS_ADDRESSES_H
#include "gnunet_util_lib.h"
#include "gnunet_ats_service.h"
#include "gnunet-service-ats.h"
#include "ats.h"
/**
* NOTE: Do not change this documentation. This documentation is based on
* gnunet.org:/vcs/fsnsg/ats-paper.git/tech-doku/ats-tech-guide.tex
* use build_txt.sh to generate plaintext output
*
* 1 ATS addresses : ATS address management
*
* This ATS addresses ("addresses") component manages the addresses known to
* ATS service and suggests addresses to transport service when it is
* interested in address suggestion for a peer. ATS addresses also
* instantiates the bandwidth assignment mechanism (solver), notifies it
* about changes to addresses and forwards changes to bandwidth assignments
* to transport, depending if transport is interested in this change.
*
* 1.1 Input data
*
* 1.1.1 Addresses
*
* Addresses are added by specifying peer ID, plugin, address, address length
* and session, if available. ATS information can be specified if available.
*
* 1.1.2 Networks
*
* ATS specifies a fix set of networks an address can belong to. For each
* network an inbound and outbound quota will be specified. The available
* networks and addtional helper varaibles are defined in
* gnunet_ats_service.h. At the moment 5 networks are defined:
* * GNUNET_NT_UNSPECIFIED
* * GNUNET_NT_LOOPBACK
* * GNUNET_NT_LAN
* * GNUNET_NT_WAN
* * GNUNET_NT_WLAN
*
* The total number of networks defined is stored in
* GNUNET_NT_COUNT GNUNET_ATS_NetworkType can be used array
* initializer for an int array, while GNUNET_ATS_NetworkType is an
* initializer for a char array containing a string description of all
* networks
*
* 1.1.3 Quotas
*
* An inbound and outbound quota for each of the networks mentioned in 1.1.2
* is loaded from ats configuration during initialization. This quota defines
* to total amount of inbound and outbound traffic allowed for a specific
* network. The configuration values used are in section ats:
* * "NETWORK"_QUOTA_IN =
* * "NETWORK"_QUOTA_IN =
*
* You can specify quotas by setting the to a:
* * unrestricted: unlimited
* * number of bytes: e.g. 10240
* * fancy value: e.g. 64 Kib
*
* unlimited is defined as GNUNET_ATS_MaxBandwidthString and equivalent to
* the value GNUNET_ATS_MaxBandwidth Important predefined values for quotas
* are:
* * GNUNET_ATS_DefaultBandwidth: 65536
* * GNUNET_ATS_MaxBandwidth: UINT32_MAX
* * GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT: 1024
*
* Details of loading quotas and default values will be described on
*
* 1.1.4 Preference values
*
* 1.2 Data structures used
*
* Addresse uses struct ATS_Address for each address. The structs are stored
* in a linked list and provides a pointer void *solver_information for the
* solver to store address specific information. It provides the int values
* active which is set to GNUNET_YES if the address is select for transport
* use and used, representing that transport service is actively using this
* address. Address information are stored in peer, addr, addr_len, plugin.
*
* 1.3 Initialization
*
* During initialization a hashmap to store addresses is created. The quotas
* for all networks defined for ATS are loaded from configuration. For each
* network first the logic will check if the string
* GNUNET_ATS_MaxBandwidthString is configured, if not it will try to convert
* the configured value as a fancy size and if this fails it will try to use
* it as a value_number. If no configuration value is found it will assign
* GNUNET_ATS_DefaultBandwidth. The most important step is to load the
* configured solver using configuration "[ats]:MODE". Current solvers are
* MODE_PROPORTIONAL, MODE_MLP. Interaction is done using a solver API
*
* 1.4 Solver API
*
* Solver functions:
* * s_init: init the solver with required information
* * s_add: add a new address
* * s_update: update ATS values or session for an address
* * s_get: get prefered address for a peer
* * s_del: delete an address
* * s_pref: change preference value for a peer
* * s_done: shutdown solver
*
* Callbacks: addresses provides a bandwidth_changed_cb callback to the
* solver which is called when bandwidth assigned to peer has changed
*
* 1.5 Shutdown
*
* During shutdown all addresses are freed and the solver told to shutdown
*
* 1.6 Addresses and sessions
*
* Addresses consist of the address itself and a numerical session. When a
* new address without a session is added it has no session, so it gets
* session 0 assigned. When an address with a session is added and an address
* object with session 0 is found, this object is updated with the session
* otherwise a new address object with this session assigned is created.
*
* 1.6.1 Terminology
*
* Addresses a1,a2 with session s1, s2 are "exact" if:
* (a1 == a2)&&(s1 == s2)
* Addresses a1,a2 with session s1, s2 are "equivalent" if:
* (a1 == a2)&&((s1 == s2)||(s1 == 0)||(s2 == 0)
*
* 1.7 Address management
*
* Transport service notifies ATS about changes to the addresses known to
* it.
*
* 1.7.1 Adding an address
*
* When transport learns a new address it tells ATS and ATS is telling
* addresses about it using GAS_address_add. If not known to addresses it
* creates a new address object and calls solver's s_add. ATS information are
* deserialized and solver is notified about the session and ATS information
* using s_update.
*
* 1.7.2 Updating an address
*
* Addresses does an lookup up for the existing address with the given
* session. If disassembles included ATS information and notifies the solver
* using s_update about the update.
*
* 1.7.3 Deleting an address
*
* Addresses does an lookup for the exact address and session and if removes
* this address. If session != 0 the session is set to 0 and the address is
* kept. If session == 0, the addresses is removed.
*
* 1.7.4 Requesting an address suggestion
*
* The address client issues a request address message to be notified about
* address suggestions for a specific peer. Addresses asks the solver with
* s_get. If no address is available, it will not send a response, otherwise
* it will respond with the choosen address.
*
* 1.7.5 Address suggestions
*
* Addresses will notify the client automatically on any bandwidth_changed_cb
* by the solver if a address suggestion request is pending. If no address is
* available it will not respond at all If the client is not interested
* anymore, it has to cancel the address suggestion request.
*
* 1.7.6 Suggestions blocks and reset
*
* After suggesting an address it is blocked for ATS_BLOCKING_DELTA sec. to
* prevent the client from being thrashed. If the client requires immediately
* it can reset this block using GAS_addresses_handle_backoff_reset.
*
* 1.7.7 Address lifecycle
*
* * (add address)
* * (updated address)
* * (delete address)
*
* 1.8 Bandwidth assignment
*
* The addresses are used to perform resource allocation operations. ATS
* addresses takes care of instantiating the solver configured and notifies
* the respective solver about address changes and receives changes to the
* bandwidth assignment from the solver. The current bandwidth assignment is
* sent to transport. The specific solvers will be described in the specific
* section.
*
* 1.9 Changing peer preferences
*
* The bandwidth assigned to a peer can be influenced by setting a preference
* for a peer. The prefernce will be given to to the solver with s_pref which
* has to take care of the preference value
*/
/*
* How long will address suggestions blocked after a suggestion
*/
#define ATS_BLOCKING_DELTA GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MILLISECONDS, 100)
/**
* Information provided by ATS normalization
*/
struct GAS_NormalizationInfo
{
/**
* Next index to use in averaging queue
*/
unsigned int avg_queue_index;
/**
* Averaging queue
*/
uint64_t atsi_abs[GAS_normalization_queue_length];
/**
* Averaged ATSI values from queue
*/
uint64_t avg;
/**
* Normalized values from queue to a range of values [1.0...2.0]
*/
double norm;
};
/**
* Address with additional information
*/
struct ATS_Address
{
/**
* Peer ID this address is for.
*/
struct GNUNET_PeerIdentity peer;
/**
* Address (in plugin-specific binary format).
*/
const void *addr;
/**
* Plugin name
*/
char *plugin;
/**
* Solver-specific information for this address
*/
void *solver_information;
/**
* ATS performance information for this address
*/
struct GNUNET_ATS_Properties properties;
/**
* Time when address had last activity (update, in uses)
*/
struct GNUNET_TIME_Absolute t_last_activity;
/**
* Time when address was added
*/
struct GNUNET_TIME_Absolute t_added;
/**
* Address length, number of bytes in @e addr.
*/
size_t addr_len;
/**
* Session ID, can never be 0.
*/
uint32_t session_id;
/**
* Field to store local flags.
*/
enum GNUNET_HELLO_AddressInfo local_address_info;
/**
* ATS performance information for this address, size of the @e atsi array.
*/
uint32_t atsi_count;
/**
* Inbound bandwidth assigned by solver
*/
uint32_t assigned_bw_in;
/**
* Outbound bandwidth assigned by solver
*/
uint32_t assigned_bw_out;
/**
* Inbound bandwidth assigned by solver in NBO
*/
uint32_t last_notified_bw_in;
/**
* Outbound bandwidth assigned by solver in NBO
*/
uint32_t last_notified_bw_out;
/**
* Is this the active address for this peer?
*/
int active;
/**
* Normalized delay information for this address.
*/
struct GAS_NormalizationInfo norm_delay;
/**
* Normalized distance information for this address.
*/
struct GAS_NormalizationInfo norm_distance;
/**
* Normalized utilization inbound for this address.
*/
struct GAS_NormalizationInfo norm_utilization_in;
/**
* Normalized utilization outbound for this address.
*/
struct GAS_NormalizationInfo norm_utilization_out;
};
/**
* A multipeermap mapping peer identities to `struct ATS_Address`.
*/
extern struct GNUNET_CONTAINER_MultiPeerMap *GSA_addresses;
/**
* Initialize address subsystem. The addresses subsystem manages the addresses
* known and current performance information.
*/
void
GAS_addresses_init (void);
/**
* Shutdown address subsystem.
*/
void
GAS_addresses_done (void);
/**
* Add a new address for a peer.
*
* @param peer peer
* @param plugin_name transport plugin name
* @param plugin_addr plugin address
* @param plugin_addr_len length of the @a plugin_addr
* @param local_address_info the local address for the address
* @param session_id session id, can never be 0.
* @param prop performance information for this address
*/
void
GAS_addresses_add (const struct GNUNET_PeerIdentity *peer,
const char *plugin_name,
const void *plugin_addr,
size_t plugin_addr_len,
uint32_t local_address_info,
uint32_t session_id,
const struct GNUNET_ATS_Properties *prop);
/**
* Update an address with new performance information for a peer.
*
* @param peer peer
* @param session_id session id, can never be 0
* @param prop performance information for this address
*/
void
GAS_addresses_update (const struct GNUNET_PeerIdentity *peer,
uint32_t session_id,
const struct GNUNET_ATS_Properties *prop);
/**
* Remove an address for a peer.
*
* @param peer peer
* @param session_id session id, can never be 0
*/
void
GAS_addresses_destroy (const struct GNUNET_PeerIdentity *peer,
uint32_t session_id);
/**
* Remove all addresses.
*/
void
GAS_addresses_destroy_all (void);
/**
* Iterator for #GAS_addresses_get_peer_info()
*
* @param cls closure
* @param id the peer id
* @param plugin_name plugin name
* @param plugin_addr address
* @param plugin_addr_len length of @a plugin_addr
* @param address_active is address actively used
* @param atsi ats performance information
* @param local_address_info flags for the address
* @param bandwidth_out current outbound bandwidth assigned to address
* @param bandwidth_in current inbound bandwidth assigned to address
*/
typedef void
(*GNUNET_ATS_PeerInfo_Iterator) (void *cls,
const struct GNUNET_PeerIdentity *id,
const char *plugin_name,
const void *plugin_addr,
size_t plugin_addr_len,
const int address_active,
const struct GNUNET_ATS_Properties *prop,
enum GNUNET_HELLO_AddressInfo local_address_info,
struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out,
struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in);
/**
* Return information all peers currently known to ATS
*
* @param peer the respective peer
* @param pi_it the iterator to call for every peer
* @param pi_it_cls the closure for @a pi_it
*/
void
GAS_addresses_get_peer_info (const struct GNUNET_PeerIdentity *peer,
GNUNET_ATS_PeerInfo_Iterator pi_it,
void *pi_it_cls);
/**
* Handle 'address list request' messages from clients.
*
* @param client client that sent the request
* @param alrm the request message
*/
void
GAS_handle_request_address_list (struct GNUNET_SERVICE_Client *client,
const struct AddressListRequestMessage *alrm);
#endif
/* end of gnunet-service-ats_addresses.h */