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3 (C) 2009 Christian Grothoff (and other contributing authors)
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22 * @file include/gnunet_transport_service.h
23 * @brief low-level P2P IO
24 * @author Christian Grothoff
27 #ifndef GNUNET_TRANSPORT_SERVICE_H
28 #define GNUNET_TRANSPORT_SERVICE_H
33 #if 0 /* keep Emacsens' auto-indent happy */
38 #include "gnunet_bandwidth_lib.h"
39 #include "gnunet_configuration_lib.h"
40 #include "gnunet_crypto_lib.h"
41 #include "gnunet_connection_lib.h"
42 #include "gnunet_scheduler_lib.h"
43 #include "gnunet_time_lib.h"
46 * Version number of the transport API.
48 #define GNUNET_TRANSPORT_VERSION 0x00000000
52 * Enum defining all known property types for ATS Enum values are used
53 * in the GNUNET_TRANSPORT_ATS_Information struct as
56 * Cost are always stored in uint32_t, so all units used to define costs
57 * have to be normalized to fit in uint32_t [0 .. 4.294.967.295]
59 * To keep the elements ordered
60 * 1..1024 : Values with a relation to cost
61 * 1025..2048 : Values with a relation to quality
62 * 2049..3072 : Values with a relation to availability
65 enum GNUNET_TRANSPORT_ATS_Property
71 GNUNET_TRANSPORT_ATS_ARRAY_TERMINATOR = 0,
73 /* Cost related values */
74 /* =================== */
77 * Volume based cost in financial units to transmit data
79 * Note: This value is not bound to a specific currency or unit and only
81 * "cent" just refers the smallest amount of money in the respective
86 * Interpretation: less is better
92 GNUNET_TRANSPORT_ATS_COST_FINANCIAL_PER_VOLUME = 1,
95 * Time based cost in financial units to transmit data
97 * Note: This value is not bound to a specific currency or unit and only
99 * "cent" just refers the smallest amount of money in the respective
104 * Interpretation: less is better
108 * Dialup: 10 [cent/h]
110 GNUNET_TRANSPORT_ATS_COST_FINANCIAL_PER_TIME = 2,
113 * Computational costs
115 * Effort of preparing data to be sent with this transport
116 * Includes encoding, encryption and conversion of data
117 * Partial values can be summed up: c_sum = c_enc + c_enc + c_conv
118 * Resulting values depend on local system properties, e.g. CPU
122 * Interpretation: less is better
126 * HTTPS with AES CBC-256: 7,382
127 * HTTPS with AES CBC-128: 5,279
128 * HTTPS with RC4-1024: 2,652
130 GNUNET_TRANSPORT_ATS_COST_COMPUTATIONAL = 3,
135 * Energy consumption using this transport when sending with a certain
136 * power at a certain bitrate. This is only an approximation based on:
137 * Energy consumption E = P / D
140 * Power P in Watt (J/s)
141 * Datarate D in MBit/s
143 * Conversion between power P and dBm used by WLAN in radiotap's dBm TX power:
145 * Lp(dbm) = 10 log10 (P/ 1mW)
147 * => P = 1 mW * 10^(Lp(dbm)/10)
151 * Interpretation: less is better
156 * WLAN: 89 (600 mW @ 802.11g /w 54 MBit/s)
157 * Bluetooth: 267 (100 mW @ BT2.0 EDR /w 3 MBit/s)
159 GNUNET_TRANSPORT_ATS_COST_ENERGY_CONSUMPTION = 4,
163 * How many bytes are transmitted to initiate a new connection using
168 * Interpretation: less is better
172 * UDP (No connection) :
174 * TCP (TCP 3-Way handshake):
175 * 220 bytes Ethernet, 172 bytes TCP/IP, 122 bytes TCP
176 * HTTP (TCP + Header) :
177 * 477 bytes Ethernet, 429 bytes TCP/IP, 374 bytes TCP, 278 bytes HTTP
178 * HTTPS HTTP+TLS Handshake:
179 * 2129 bytes Ethernet, 1975 bytes TCP/IP, 1755 bytes TCP, 1403 bytes HTTPS
182 GNUNET_TRANSPORT_ATS_COST_CONNECT = 5,
187 * How many bandwidth is available to consume?
188 * Used to calculate which impact sending data with this transport has
192 * Interpretation: more is better
195 * LAN: 12,800 (100 MBit/s)
196 * WLAN: 6,912 (54 MBit/s)
197 * Dial-up: 8 (64 Kbit/s)
200 GNUNET_TRANSPORT_ATS_COST_BANDWITH_AVAILABLE = 6,
205 * How many bytes are sent over the wire when 1 kilobyte (1024 bytes)
206 * of application data is transmitted?
207 * A factor used with connect cost, bandwidth cost and energy cost
208 * to describe the overhead produced by the transport protocol
212 * Interpretation: less is better
216 * TCP/IPv4 over Ethernet: 1024 + 38 + 20 + 20 = 1102 [bytes/kb]
217 * TCP/IPv6 over Ethernet: 1024 + 38 + 20 + 40 = 1122 [bytes/kb]
218 * UDP/IPv4 over Ethernet: 1024 + 38 + 20 + 8 = 1090 [bytes/kb]
219 * UDP/IPv6 over Ethernet: 1024 + 38 + 40 + 8 = 1110 [bytes/kb]
221 GNUNET_TRANSPORT_ATS_COST_NETWORK_OVERHEAD = 7,
224 /* Quality related values */
225 /* ====================== */
227 /* Physical layer quality properties */
230 * Signal strength on physical layer
234 GNUNET_TRANSPORT_ATS_QUALITY_PHY_SIGNAL_STRENGTH = 1025,
237 * Collision rate on physical layer
241 GNUNET_TRANSPORT_ATS_QUALITY_PHY_COLLISION_RATE = 1026,
244 * Error rate on physical layer
248 GNUNET_TRANSPORT_ATS_QUALITY_PHY_ERROR_RATE = 1027,
250 /* Network layer quality properties */
254 * Time between when the time packet is sent and the packet arrives
264 GNUNET_TRANSPORT_ATS_QUALITY_NET_DELAY = 1028,
268 * Time variations of the delay
269 * 1st derivative of a delay function
273 GNUNET_TRANSPORT_ATS_QUALITY_NET_JITTER = 1029,
276 * Error rate on network layer
285 * Note: This numbers are just assumptions as an example, not
286 * measured or somehow determined
288 GNUNET_TRANSPORT_ATS_QUALITY_NET_ERRORRATE = 1030,
291 * Drop rate on network layer
292 * Bytes actively dismissed by a network component during transmission
293 * Reasons for dropped data can be full queues, congestion, quota violations...
302 * Note: This numbers are just assumptions as an example, not
303 * measured or somehow determined
305 GNUNET_TRANSPORT_ATS_QUALITY_NET_DROPRATE = 1031,
308 * Loss rate on network layer
309 * Bytes lost during transmission
310 * Reasons can be collisions, ...
319 * Note: This numbers are just assumptions as an example, not measured
320 * or somehow determined
322 GNUNET_TRANSPORT_ATS_QUALITY_NET_LOSSRATE = 1032,
325 * Throughput on network layer
336 GNUNET_TRANSPORT_ATS_QUALITY_NET_THROUGHPUT = 1033,
339 * Distance on network layer
343 GNUNET_TRANSPORT_ATS_QUALITY_NET_DISTANCE = 1034,
346 /* Availability related values */
347 /* =========================== */
350 * Is a peer reachable?
352 GNUNET_TRANSPORT_ATS_AVAILABILITY_REACHABLE = 2048,
355 * Is there a connection established to a peer using this transport
357 GNUNET_TRANSPORT_ATS_AVAILABILITY_CONNECTED = 2049
362 * struct used to communicate the transport's properties like cost and
363 * quality of service as well as high-level constraints on resource
367 * +-----------+ Constraints | | Plugin properties +---------+
368 * | Highlevel |------------> |ATS| <------------------|Transport|
369 * | Component | ATS struct | | ATS struct | Plugin |
370 * +-----------+ | | +---------+
373 * This structure will be used by transport plugins to communicate
374 * costs to ATS or by higher level components to tell ATS their
375 * constraints. Always a pair of (GNUNET_TRANSPORT_ATS_Property,
376 * uint32_t value). Value is always uint32_t, so all units used to
377 * define costs have to be normalized to fit uint32_t.
379 struct GNUNET_TRANSPORT_ATS_Information
382 * ATS property type, in network byte order.
387 * ATS property value, in network byte order.
395 * Function called by the transport for each received message.
398 * @param peer (claimed) identity of the other peer
399 * @param message the message
400 * @param ats performance data
401 * @param ats_count number of entries in ats (excluding 0-termination)
403 typedef void (*GNUNET_TRANSPORT_ReceiveCallback) (void *cls,
405 GNUNET_PeerIdentity * peer,
407 GNUNET_MessageHeader *
410 GNUNET_TRANSPORT_ATS_Information
411 * ats, uint32_t ats_count);
415 * Opaque handle to the service.
417 struct GNUNET_TRANSPORT_Handle;
421 * Function called to notify transport users that another
422 * peer connected to us.
425 * @param peer the peer that connected
426 * @param ats performance data
427 * @param ats_count number of entries in ats (excluding 0-termination)
429 typedef void (*GNUNET_TRANSPORT_NotifyConnect) (void *cls,
430 const struct GNUNET_PeerIdentity
433 GNUNET_TRANSPORT_ATS_Information
434 * ats, uint32_t ats_count);
437 * Function called to notify transport users that another
438 * peer disconnected from us.
441 * @param peer the peer that disconnected
443 typedef void (*GNUNET_TRANSPORT_NotifyDisconnect) (void *cls,
445 GNUNET_PeerIdentity * peer);
449 * Function to call with a binary format of an address
452 * @param address NULL on error, otherwise 0-terminated printable UTF-8 string
454 typedef void (*GNUNET_TRANSPORT_AddressLookUpCallback) (void *cls,
455 const char *address);
459 * Function to call with a binary format of an address
462 * @param peer peer identity
463 * @param transport transport plugin
464 * @param addr address
465 * @param addrlen address length
467 typedef void (*GNUNET_TRANSPORT_AddressLookUpBinaryCallback) (void *cls,
478 * Connect to the transport service. Note that the connection may
479 * complete (or fail) asynchronously.
481 * @param cfg configuration to use
482 * @param self our own identity (API should check that it matches
483 * the identity found by transport), or NULL (no check)
484 * @param cls closure for the callbacks
485 * @param rec receive function to call
486 * @param nc function to call on connect events
487 * @param nd function to call on disconnect events
488 * @return NULL on error
490 struct GNUNET_TRANSPORT_Handle *
491 GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
492 const struct GNUNET_PeerIdentity *self, void *cls,
493 GNUNET_TRANSPORT_ReceiveCallback rec,
494 GNUNET_TRANSPORT_NotifyConnect nc,
495 GNUNET_TRANSPORT_NotifyDisconnect nd);
499 * Disconnect from the transport service.
501 * @param handle handle returned from connect
504 GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle);
508 * Ask the transport service to establish a connection to
511 * @param handle connection to transport service
512 * @param target who we should try to connect to
515 GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle,
516 const struct GNUNET_PeerIdentity *target);
520 * Set the share of incoming/outgoing bandwidth for the given
521 * peer to the specified amount.
523 * @param handle connection to transport service
524 * @param target who's bandwidth quota is being changed
525 * @param quota_in incoming bandwidth quota
526 * @param quota_out outgoing bandwidth quota
529 GNUNET_TRANSPORT_set_quota (struct GNUNET_TRANSPORT_Handle *handle,
530 const struct GNUNET_PeerIdentity *target,
531 struct GNUNET_BANDWIDTH_Value32NBO quota_in,
532 struct GNUNET_BANDWIDTH_Value32NBO quota_out);
536 * Opaque handle for a transmission-ready request.
538 struct GNUNET_TRANSPORT_TransmitHandle;
542 * Check if we could queue a message of the given size for
543 * transmission. The transport service will take both its internal
544 * buffers and bandwidth limits imposed by the other peer into
545 * consideration when answering this query.
547 * @param handle connection to transport service
548 * @param target who should receive the message
549 * @param size how big is the message we want to transmit?
550 * @param priority how important is the message? @deprecated - remove?
551 * @param timeout after how long should we give up (and call
552 * notify with buf NULL and size 0)?
553 * @param notify function to call when we are ready to
554 * send such a message
555 * @param notify_cls closure for notify
556 * @return NULL if someone else is already waiting to be notified
557 * non-NULL if the notify callback was queued (can be used to cancel
558 * using GNUNET_TRANSPORT_notify_transmit_ready_cancel)
560 struct GNUNET_TRANSPORT_TransmitHandle *
561 GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle,
562 const struct GNUNET_PeerIdentity
563 *target, size_t size, uint32_t priority,
564 struct GNUNET_TIME_Relative timeout,
565 GNUNET_CONNECTION_TransmitReadyNotify
566 notify, void *notify_cls);
570 * Cancel the specified transmission-ready notification.
572 * @param th handle of the transmission notification request to cancel
575 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct
576 GNUNET_TRANSPORT_TransmitHandle
582 * Function called whenever there is an update to the
583 * HELLO of this peer.
586 * @param hello our updated HELLO
588 typedef void (*GNUNET_TRANSPORT_HelloUpdateCallback) (void *cls,
590 GNUNET_MessageHeader *
595 * Handle to cancel a 'GNUNET_TRANSPORT_get_hello' operation.
597 struct GNUNET_TRANSPORT_GetHelloHandle;
601 * Obtain updates on changes to the HELLO message for this peer.
603 * @param handle connection to transport service
604 * @param rec function to call with the HELLO
605 * @param rec_cls closure for rec
606 * @return handle to cancel the operation
608 struct GNUNET_TRANSPORT_GetHelloHandle *
609 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
610 GNUNET_TRANSPORT_HelloUpdateCallback rec,
615 * Stop receiving updates about changes to our HELLO message.
617 * @param ghh handle returned from 'GNUNET_TRANSPORT_get_hello')
620 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh);
624 * Offer the transport service the HELLO of another peer. Note that
625 * the transport service may just ignore this message if the HELLO is
626 * malformed or useless due to our local configuration.
628 * @param handle connection to transport service
629 * @param hello the hello message
630 * @param cont continuation to call when HELLO has been sent
631 * @param cls closure for continuation
634 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
635 const struct GNUNET_MessageHeader *hello,
636 GNUNET_SCHEDULER_Task cont, void *cls);
640 * Handle to cancel a pending address lookup.
642 struct GNUNET_TRANSPORT_AddressLookupContext;
646 * Convert a binary address into a human readable address.
648 * @param cfg configuration to use
649 * @param address address to convert (binary format)
650 * @param addressLen number of bytes in address
651 * @param numeric should (IP) addresses be displayed in numeric form
652 * (otherwise do reverse DNS lookup)
653 * @param nameTrans name of the transport to which the address belongs
654 * @param timeout how long is the lookup allowed to take at most
655 * @param aluc function to call with the results
656 * @param aluc_cls closure for aluc
657 * @return handle to cancel the operation, NULL on error
659 struct GNUNET_TRANSPORT_AddressLookupContext *
660 GNUNET_TRANSPORT_address_lookup (const struct GNUNET_CONFIGURATION_Handle *cfg,
661 const char *address, size_t addressLen,
662 int numeric, const char *nameTrans,
663 struct GNUNET_TIME_Relative timeout,
664 GNUNET_TRANSPORT_AddressLookUpCallback aluc,
669 * Cancel request for address conversion.
671 * @param alc handle for the request to cancel
674 GNUNET_TRANSPORT_address_lookup_cancel (struct
675 GNUNET_TRANSPORT_AddressLookupContext
680 * Handle to cancel a pending address lookup.
682 struct GNUNET_TRANSPORT_AddressLookupContext;
686 * Return all the known addresses for a peer. FIXME: document better!
687 * FIXME: use better name!
689 * @param cfg configuration to use
690 * @param peer peer identity to look up the addresses of
691 * @param timeout how long is the lookup allowed to take at most
692 * @param peer_address_callback function to call with the results
693 * @param peer_address_callback_cls closure for peer_address_callback
695 struct GNUNET_TRANSPORT_PeerAddressLookupContext *
696 GNUNET_TRANSPORT_peer_address_lookup (const struct GNUNET_CONFIGURATION_Handle
698 const struct GNUNET_PeerIdentity *peer,
699 struct GNUNET_TIME_Relative timeout,
700 GNUNET_TRANSPORT_AddressLookUpCallback
701 peer_address_callback,
702 void *peer_address_callback_cls);
706 * Cancel request for peer lookup.
708 * @param alc handle for the request to cancel
711 GNUNET_TRANSPORT_peer_address_lookup_cancel (struct
712 GNUNET_TRANSPORT_PeerAddressLookupContext
717 * Return all the known addresses. FIXME: document better!
718 * FIXME: use better name! FIXME: extend API to allow cancellation!
720 * @param cfg configuration to use
721 * @param timeout how long is the lookup allowed to take at most
722 * @param peer_address_callback function to call with the results
723 * @param peer_address_callback_cls closure for peer_address_callback
726 GNUNET_TRANSPORT_address_iterate (const struct GNUNET_CONFIGURATION_Handle *cfg,
727 struct GNUNET_TIME_Relative timeout,
728 GNUNET_TRANSPORT_AddressLookUpBinaryCallback
729 peer_address_callback,
730 void *peer_address_callback_cls);
734 * Handle for blacklisting peers.
736 struct GNUNET_TRANSPORT_Blacklist;
740 * Function that decides if a connection is acceptable or not.
743 * @param pid peer to approve or disapproave
744 * @return GNUNET_OK if the connection is allowed
746 typedef int (*GNUNET_TRANSPORT_BlacklistCallback) (void *cls,
748 GNUNET_PeerIdentity * pid);
752 * Install a blacklist callback. The service will be queried for all
753 * existing connections as well as any fresh connections to check if
754 * they are permitted. If the blacklisting callback is unregistered,
755 * all hosts that were denied in the past will automatically be
756 * whitelisted again. Cancelling the blacklist handle is also the
757 * only way to re-enable connections from peers that were previously
760 * @param cfg configuration to use
761 * @param cb callback to invoke to check if connections are allowed
762 * @param cb_cls closure for cb
763 * @return NULL on error, otherwise handle for cancellation
765 struct GNUNET_TRANSPORT_Blacklist *
766 GNUNET_TRANSPORT_blacklist (const struct GNUNET_CONFIGURATION_Handle *cfg,
767 GNUNET_TRANSPORT_BlacklistCallback cb,
772 * Abort the blacklist. Note that this function is the only way for
773 * removing a peer from the blacklist.
775 * @param br handle of the request that is to be cancelled
778 GNUNET_TRANSPORT_blacklist_cancel (struct GNUNET_TRANSPORT_Blacklist *br);
782 #if 0 /* keep Emacsens' auto-indent happy */
789 /* ifndef GNUNET_TRANSPORT_SERVICE_H */
791 /* end of gnunet_transport_service.h */