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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,
338 /* Availability related values */
339 /* =========================== */
342 * Is a peer reachable?
344 GNUNET_TRANSPORT_ATS_AVAILABILITY_REACHABLE = 2048,
347 * Is there a connection established to a peer using this transport
349 GNUNET_TRANSPORT_ATS_AVAILABILITY_CONNECTED = 2049
355 * struct used to communicate the transport's properties like cost and
356 * quality of service as well as high-level constraints on resource
360 * +-----------+ Constraints | | Plugin properties +---------+
361 * | Highlevel |------------> |ATS| <------------------|Transport|
362 * | Component | ATS struct | | ATS struct | Plugin |
363 * +-----------+ | | +---------+
366 * This structure will be used by transport plugins to communicate
367 * costs to ATS or by higher level components to tell ATS their
368 * constraints. Always a pair of (GNUNET_TRANSPORT_ATS_Property,
369 * uint32_t value). Value is always uint32_t, so all units used to
370 * define costs have to be normalized to fit uint32_t.
372 struct GNUNET_TRANSPORT_ATS_Information
375 * ATS property type, in network byte order.
380 * ATS property value, in network byte order.
389 * Function called by the transport for each received message.
392 * @param peer (claimed) identity of the other peer
393 * @param message the message
394 * @param latency estimated latency for communicating with the
395 * given peer (round-trip)
396 * @param distance in overlay hops, as given by transport plugin
398 typedef void (*GNUNET_TRANSPORT_ReceiveCallback) (void *cls,
400 GNUNET_PeerIdentity * peer,
402 GNUNET_MessageHeader *
404 const struct GNUNET_TRANSPORT_ATS_Information *ats,
409 * Opaque handle to the service.
411 struct GNUNET_TRANSPORT_Handle;
415 * Function called to notify transport users that another
416 * peer connected to us.
419 * @param peer the peer that connected
420 * @param latency estimated latency for communicating with the
421 * given peer (round-trip)
422 * @param distance in overlay hops, as given by transport plugin
425 (*GNUNET_TRANSPORT_NotifyConnect) (void *cls,
426 const struct GNUNET_PeerIdentity * peer,
427 const struct GNUNET_TRANSPORT_ATS_Information *ats,
431 * Function called to notify transport users that another
432 * peer disconnected from us.
435 * @param peer the peer that disconnected
438 (*GNUNET_TRANSPORT_NotifyDisconnect) (void *cls,
439 const struct GNUNET_PeerIdentity *
444 * Function to call with a human-readable format of an address
447 * @param address NULL on error, otherwise 0-terminated printable UTF-8 string
450 (*GNUNET_TRANSPORT_AddressLookUpCallback) (void *cls,
451 const char *address);
455 * Connect to the transport service. Note that the connection may
456 * complete (or fail) asynchronously.
458 * @param cfg configuration to use
459 * @param self our own identity (API should check that it matches
460 * the identity found by transport), or NULL (no check)
461 * @param cls closure for the callbacks
462 * @param rec receive function to call
463 * @param nc function to call on connect events
464 * @param nd function to call on disconnect events
465 * @return NULL on error
467 struct GNUNET_TRANSPORT_Handle *GNUNET_TRANSPORT_connect (const struct
468 GNUNET_CONFIGURATION_Handle
470 const struct GNUNET_PeerIdentity *self,
472 GNUNET_TRANSPORT_ReceiveCallback
474 GNUNET_TRANSPORT_NotifyConnect
476 GNUNET_TRANSPORT_NotifyDisconnect
481 * Disconnect from the transport service.
483 * @param handle handle returned from connect
485 void GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle);
489 * Set the share of incoming/outgoing bandwidth for the given
490 * peer to the specified amount.
492 * @param handle connection to transport service
493 * @param target who's bandwidth quota is being changed
494 * @param quota_in incoming bandwidth quota
495 * @param quota_out outgoing bandwidth quota
496 * @param timeout how long to wait until signaling failure if
497 * we can not communicate the quota change
498 * @param cont continuation to call when done, will be called
499 * either with reason "TIMEOUT" or with reason "PREREQ_DONE"
500 * @param cont_cls closure for continuation
503 GNUNET_TRANSPORT_set_quota (struct GNUNET_TRANSPORT_Handle *handle,
504 const struct GNUNET_PeerIdentity *target,
505 struct GNUNET_BANDWIDTH_Value32NBO quota_in,
506 struct GNUNET_BANDWIDTH_Value32NBO quota_out,
507 struct GNUNET_TIME_Relative timeout,
508 GNUNET_SCHEDULER_Task cont, void *cont_cls);
512 * Opaque handle for a transmission-ready request.
514 struct GNUNET_TRANSPORT_TransmitHandle;
518 * Check if we could queue a message of the given size for
519 * transmission. The transport service will take both its internal
520 * buffers and bandwidth limits imposed by the other peer into
521 * consideration when answering this query.
523 * @param handle connection to transport service
524 * @param target who should receive the message
525 * @param size how big is the message we want to transmit?
526 * @param priority how important is the message?
527 * @param timeout after how long should we give up (and call
528 * notify with buf NULL and size 0)?
529 * @param notify function to call when we are ready to
530 * send such a message
531 * @param notify_cls closure for notify
532 * @return NULL if someone else is already waiting to be notified
533 * non-NULL if the notify callback was queued (can be used to cancel
534 * using GNUNET_TRANSPORT_notify_transmit_ready_cancel)
536 struct GNUNET_TRANSPORT_TransmitHandle
537 *GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle
539 const struct GNUNET_PeerIdentity
540 *target, size_t size,
542 struct GNUNET_TIME_Relative
544 GNUNET_CONNECTION_TransmitReadyNotify
545 notify, void *notify_cls);
549 * Cancel the specified transmission-ready notification.
551 * @param h handle of the transmission notification request to cancel
554 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct
555 GNUNET_TRANSPORT_TransmitHandle
561 * Function called whenever there is an update to the
562 * HELLO of this peer.
565 * @param hello our updated HELLO
567 typedef void (*GNUNET_TRANSPORT_HelloUpdateCallback)(void *cls,
568 const struct GNUNET_MessageHeader *hello);
572 * Obtain updates on changes to the HELLO message for this peer.
574 * @param handle connection to transport service
575 * @param rec function to call with the HELLO
576 * @param rec_cls closure for rec
579 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
580 GNUNET_TRANSPORT_HelloUpdateCallback rec,
585 * Stop receiving updates about changes to our HELLO message.
587 * @param handle connection to transport service
588 * @param rec function previously registered to be called with the HELLOs
589 * @param rec_cls closure for rec
592 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_Handle *handle,
593 GNUNET_TRANSPORT_HelloUpdateCallback rec,
598 * Offer the transport service the HELLO of another peer. Note that
599 * the transport service may just ignore this message if the HELLO is
600 * malformed or useless due to our local configuration. If the HELLO
601 * is working, we should add it to PEERINFO.
603 * @param handle connection to transport service
604 * @param hello the hello message
607 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
608 const struct GNUNET_MessageHeader *hello);
612 * Convert a binary address into a human readable address.
614 * @param cfg configuration to use
615 * @param address address to convert (binary format)
616 * @param addressLen number of bytes in address
617 * @param numeric should (IP) addresses be displayed in numeric form
618 * (otherwise do reverse DNS lookup)
619 * @param nameTrans name of the transport to which the address belongs
620 * @param timeout how long is the lookup allowed to take at most
621 * @param aluc function to call with the results
622 * @param aluc_cls closure for aluc
625 GNUNET_TRANSPORT_address_lookup (const struct GNUNET_CONFIGURATION_Handle *cfg,
626 const char * address,
629 const char * nameTrans,
630 struct GNUNET_TIME_Relative timeout,
631 GNUNET_TRANSPORT_AddressLookUpCallback aluc,
637 * Handle for blacklisting peers.
639 struct GNUNET_TRANSPORT_Blacklist;
643 * Function that decides if a connection is acceptable or not.
646 * @param pid peer to approve or disapproave
647 * @return GNUNET_OK if the connection is allowed
649 typedef int (*GNUNET_TRANSPORT_BlacklistCallback)(void *cls,
650 const struct GNUNET_PeerIdentity *pid);
654 * Install a blacklist callback. The service will be queried for all
655 * existing connections as well as any fresh connections to check if
656 * they are permitted. If the blacklisting callback is unregistered,
657 * all hosts that were denied in the past will automatically be
658 * whitelisted again. Cancelling the blacklist handle is also the
659 * only way to re-enable connections from peers that were previously
662 * @param cfg configuration to use
663 * @param cb callback to invoke to check if connections are allowed
664 * @param cb_cls closure for cb
665 * @return NULL on error, otherwise handle for cancellation
667 struct GNUNET_TRANSPORT_Blacklist *
668 GNUNET_TRANSPORT_blacklist (const struct GNUNET_CONFIGURATION_Handle *cfg,
669 GNUNET_TRANSPORT_BlacklistCallback cb,
674 * Abort the blacklist. Note that this function is the only way for
675 * removing a peer from the blacklist.
677 * @param br handle of the request that is to be cancelled
680 GNUNET_TRANSPORT_blacklist_cancel (struct GNUNET_TRANSPORT_Blacklist *br);
684 #if 0 /* keep Emacsens' auto-indent happy */
691 /* ifndef GNUNET_TRANSPORT_SERVICE_H */
693 /* end of gnunet_transport_service.h */