2 This file is part of GNUnet.
3 Copyright (C) 2010-2015 Christian Grothoff (and other contributing authors)
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22 * @file transport/gnunet-service-transport_neighbours.c
23 * @brief neighbour management
24 * @author Christian Grothoff
27 #include "gnunet_ats_service.h"
28 #include "gnunet-service-transport_ats.h"
29 #include "gnunet-service-transport_blacklist.h"
30 #include "gnunet-service-transport_clients.h"
31 #include "gnunet-service-transport_neighbours.h"
32 #include "gnunet-service-transport_manipulation.h"
33 #include "gnunet-service-transport_plugins.h"
34 #include "gnunet-service-transport_validation.h"
35 #include "gnunet-service-transport.h"
36 #include "gnunet_peerinfo_service.h"
37 #include "gnunet_constants.h"
38 #include "transport.h"
42 * Size of the neighbour hash map.
44 #define NEIGHBOUR_TABLE_SIZE 256
47 * Time we give plugin to transmit DISCONNECT message before the
48 * neighbour entry self-destructs.
50 #define DISCONNECT_SENT_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, 500)
53 * How often must a peer violate bandwidth quotas before we start
54 * to simply drop its messages?
56 #define QUOTA_VIOLATION_DROP_THRESHOLD 10
59 * How long are we willing to wait for a response from ATS before timing out?
61 #define ATS_RESPONSE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
64 * How long are we willing to wait for an ACK from the other peer before
65 * giving up on our connect operation?
67 #define SETUP_CONNECTION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
70 * How long are we willing to wait for a successful reconnect if
71 * an existing connection went down? Much shorter than the
72 * usual SETUP_CONNECTION_TIMEOUT as we do not inform the
73 * higher layers about the disconnect during this period.
75 #define FAST_RECONNECT_TIMEOUT GNUNET_TIME_UNIT_SECONDS
78 * Interval to send utilization data
80 #define UTIL_TRANSMISSION_INTERVAL GNUNET_TIME_UNIT_SECONDS
83 * State describing which kind a reply this neighbour should send
88 * We did not receive a SYN message for this neighbour
93 * The neighbour received a SYN message and has to send a SYN_ACK
99 * The neighbour sent a SYN_ACK message and has to send a ACK
106 GNUNET_NETWORK_STRUCT_BEGIN
109 * Message a peer sends to another to indicate that it intends to
110 * setup a connection/session for data exchange. A 'SESSION_SYN'
111 * should be answered with a 'SESSION_SYN_ACK' with the same body
112 * to confirm. A 'SESSION_SYN_ACK' should then be followed with
113 * a 'ACK'. Once the 'ACK' is received, both peers
114 * should be connected.
116 struct TransportSynMessage
119 * Header of type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN
120 * or #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN_ACK
122 struct GNUNET_MessageHeader header;
127 uint32_t reserved GNUNET_PACKED;
130 * Absolute time at the sender. Only the most recent connect
131 * message implies which session is preferred by the sender.
133 struct GNUNET_TIME_AbsoluteNBO timestamp;
139 * Message a peer sends to another when connected to indicate that a
140 * session is in use and the peer is still alive or to respond to a keep alive.
141 * A peer sends a message with type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE
142 * to request a message with #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE_RESPONSE.
143 * When the keep alive response with type is received, transport service
144 * will call the respective plugin to update the session timeout
146 struct SessionKeepAliveMessage
149 * Header of type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE or
150 * #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE_RESPONSE.
152 struct GNUNET_MessageHeader header;
155 * A nonce to identify the session the keep alive is used for
157 uint32_t nonce GNUNET_PACKED;
161 * Message we send to the other peer to notify him that we intentionally
162 * are disconnecting (to reduce timeouts). This is just a friendly
163 * notification, peers must not rely on always receiving disconnect
166 struct SessionDisconnectMessage
169 * Header of type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT
171 struct GNUNET_MessageHeader header;
176 uint32_t reserved GNUNET_PACKED;
179 * Purpose of the signature. Extends over the timestamp.
180 * Purpose should be #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DISCONNECT.
182 struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
185 * Absolute time at the sender. Only the most recent connect
186 * message implies which session is preferred by the sender.
188 struct GNUNET_TIME_AbsoluteNBO timestamp;
191 * Public key of the sender.
193 struct GNUNET_CRYPTO_EddsaPublicKey public_key;
196 * Signature of the peer that sends us the disconnect. Only
197 * valid if the timestamp is AFTER the timestamp from the
198 * corresponding 'SYN' message.
200 struct GNUNET_CRYPTO_EddsaSignature signature;
204 GNUNET_NETWORK_STRUCT_END
208 * For each neighbour we keep a list of messages
209 * that we still want to transmit to the neighbour.
215 * This is a doubly linked list.
217 struct MessageQueue *next;
220 * This is a doubly linked list.
222 struct MessageQueue *prev;
225 * Function to call once we're done.
227 GST_NeighbourSendContinuation cont;
230 * Closure for @e cont
235 * The message(s) we want to transmit, GNUNET_MessageHeader(s)
236 * stuck together in memory. Allocated at the end of this struct.
238 const char *message_buf;
241 * Size of the message buf
243 size_t message_buf_size;
246 * At what time should we fail?
248 struct GNUNET_TIME_Absolute timeout;
254 * A possible address we could use to communicate with a neighbour.
256 struct NeighbourAddress
260 * Active session for this address.
262 struct Session *session;
265 * Network-level address information.
267 struct GNUNET_HELLO_Address *address;
270 * Timestamp of the 'SESSION_CONNECT' message we sent to the other
271 * peer for this address. Use to check that the ACK is in response
272 * to our most recent 'SYN'.
274 struct GNUNET_TIME_Absolute connect_timestamp;
277 * Inbound bandwidth from ATS for this address.
279 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in;
282 * Outbound bandwidth from ATS for this address.
284 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out;
287 * Did we tell ATS that this is our 'active' address?
292 * The current nonce sent in the last keep alive messages
294 uint32_t keep_alive_nonce;
299 * Entry in neighbours.
301 struct NeighbourMapEntry
305 * Head of list of messages we would like to send to this peer;
306 * must contain at most one message per client.
308 struct MessageQueue *messages_head;
311 * Tail of list of messages we would like to send to this peer; must
312 * contain at most one message per client.
314 struct MessageQueue *messages_tail;
317 * Are we currently trying to send a message? If so, which one?
319 struct MessageQueue *is_active;
322 * Primary address we currently use to communicate with the neighbour.
324 struct NeighbourAddress primary_address;
327 * Alternative address currently under consideration for communicating
328 * with the neighbour.
330 struct NeighbourAddress alternative_address;
333 * Identity of this neighbour.
335 struct GNUNET_PeerIdentity id;
338 * Main task that drives this peer (timeouts, keepalives, etc.).
339 * Always runs the 'master_task'.
341 struct GNUNET_SCHEDULER_Task *task;
344 * Task to disconnect neighbour after we received a DISCONNECT message
346 struct GNUNET_SCHEDULER_Task *delayed_disconnect_task;
349 * At what time should we sent the next keep-alive message?
351 struct GNUNET_TIME_Absolute keep_alive_time;
354 * At what time did we sent the last keep-alive message? Used
355 * to calculate round-trip time ("latency").
357 struct GNUNET_TIME_Absolute last_keep_alive_time;
360 * Timestamp we should include in our next SYN_ACK message.
361 * (only valid if 'send_connect_ack' is #GNUNET_YES). Used to build
362 * our SYN_ACK message.
364 struct GNUNET_TIME_Absolute connect_ack_timestamp;
367 * ATS address suggest handle
369 struct GNUNET_ATS_ConnectivitySuggestHandle *suggest_handle;
372 * Time where we should cut the connection (timeout) if we don't
373 * make progress in the state machine (or get a KEEPALIVE_RESPONSE
374 * if we are in #S_CONNECTED).
376 struct GNUNET_TIME_Absolute timeout;
379 * Tracker for inbound bandwidth.
381 struct GNUNET_BANDWIDTH_Tracker in_tracker;
384 * How often has the other peer (recently) violated the inbound
385 * traffic limit? Incremented by 10 per violation, decremented by 1
386 * per non-violation (for each time interval).
388 unsigned int quota_violation_count;
391 * The current state of the peer.
393 enum GNUNET_TRANSPORT_PeerState state;
396 * Did we sent an KEEP_ALIVE message and are we expecting a response?
398 int expect_latency_response;
401 * When a peer wants to connect we have to reply to the 1st SYN message
402 * with a SYN_ACK message. But sometime we cannot send this message
403 * immediately since we do not have an address and then we have to remember
404 * to send this message as soon as we have an address.
406 * Flag to set if we still need to send a SYN_ACK message to the other peer
407 * (once we have an address to use and the peer has been allowed by our
408 * blacklist). Initially set to #ACK_UNDEFINED. Set to #ACK_SEND_SYN_ACK
409 * if we need to send a SYN_ACK. Set to #ACK_SEND_ACK if we did
410 * send a SYN_ACK and should go to #S_CONNECTED upon receiving a
411 * 'ACK' (regardless of what our own state machine might say).
413 enum GST_ACK_State ack_state;
416 * Tracking utilization of outbound bandwidth
418 uint32_t util_total_bytes_sent;
421 * Tracking utilization of inbound bandwidth
423 uint32_t util_total_bytes_recv;
426 * Date of last utilization transmission
428 struct GNUNET_TIME_Absolute last_util_transmission;
433 * Context for blacklist checks and the #try_connect_bl_check_cont()
434 * function. Stores information about ongoing blacklist checks.
436 struct BlackListCheckContext
440 * We keep blacklist checks in a DLL.
442 struct BlackListCheckContext *next;
445 * We keep blacklist checks in a DLL.
447 struct BlackListCheckContext *prev;
450 * Address that is being checked.
452 struct NeighbourAddress na;
455 * Handle to the ongoing blacklist check.
457 struct GST_BlacklistCheck *bc;
462 * Hash map from peer identities to the respective `struct NeighbourMapEntry`.
464 static struct GNUNET_CONTAINER_MultiPeerMap *neighbours;
467 * We keep blacklist checks in a DLL so that we can find
468 * the 'sessions' in their 'struct NeighbourAddress' if
469 * a session goes down.
471 static struct BlackListCheckContext *bc_head;
474 * We keep blacklist checks in a DLL.
476 static struct BlackListCheckContext *bc_tail;
479 * List of pending blacklist checks: head
481 static struct BlacklistCheckSwitchContext *pending_bc_head;
484 * List of pending blacklist checks: tail
486 static struct BlacklistCheckSwitchContext *pending_bc_tail;
489 * counter for connected neighbours
491 static unsigned int neighbours_connected;
494 * Number of bytes we have currently queued for transmission.
496 static unsigned long long bytes_in_send_queue;
499 * Task transmitting utilization data
501 static struct GNUNET_SCHEDULER_Task *util_transmission_tk;
505 * Convert the given ACK state to a string.
508 * @return corresponding human-readable string
511 print_ack_state (enum GST_ACK_State s)
516 case ACK_SEND_SYN_ACK:
517 return "SEND_SYN_ACK";
528 * Notify our clients that another peer connected to us.
530 * @param peer the peer that connected
531 * @param bandwidth_in inbound bandwidth in NBO
532 * @param bandwidth_out outbound bandwidth in NBO
535 neighbours_connect_notification (const struct GNUNET_PeerIdentity *peer,
536 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
537 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
539 size_t len = sizeof(struct ConnectInfoMessage);
540 char buf[len] GNUNET_ALIGN;
541 struct ConnectInfoMessage *connect_msg = (struct ConnectInfoMessage *) buf;
543 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
544 "We are now connected to peer `%s'\n",
546 connect_msg->header.size = htons (sizeof(buf));
547 connect_msg->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT);
548 connect_msg->id = *peer;
549 connect_msg->quota_in = bandwidth_in;
550 connect_msg->quota_out = bandwidth_out;
551 GST_clients_broadcast (&connect_msg->header, GNUNET_NO);
556 * Notify our clients (and manipulation) that a peer disconnected from
559 * @param peer the peer that disconnected
562 neighbours_disconnect_notification (const struct GNUNET_PeerIdentity *peer)
564 struct DisconnectInfoMessage disconnect_msg;
566 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
567 "Peer `%s' disconnected\n",
569 GST_manipulation_peer_disconnect (peer);
570 disconnect_msg.header.size = htons (sizeof(struct DisconnectInfoMessage));
571 disconnect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT);
572 disconnect_msg.reserved = htonl (0);
573 disconnect_msg.peer = *peer;
574 GST_clients_broadcast (&disconnect_msg.header,
580 * Notify transport clients that a neighbour peer changed its active
583 * @param peer identity of the peer
584 * @param address address possibly NULL if peer is not connected
585 * @param state current state this peer is in
586 * @param state_timeout timeout for the current state of the peer
587 * @param bandwidth_in bandwidth assigned inbound, 0 on disconnect
588 * @param bandwidth_out bandwidth assigned outbound, 0 on disconnect
591 neighbours_changed_notification (const struct GNUNET_PeerIdentity *peer,
592 const struct GNUNET_HELLO_Address *address,
593 enum GNUNET_TRANSPORT_PeerState state,
594 struct GNUNET_TIME_Absolute state_timeout,
595 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
596 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
598 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
599 "Notifying about change for peer `%s' with address `%s' in state `%s' timing out at %s\n",
601 GST_plugins_a2s (address),
602 GNUNET_TRANSPORT_ps2s (state),
603 GNUNET_STRINGS_absolute_time_to_string (state_timeout));
604 /* FIXME: include bandwidth in notification! */
605 GST_clients_broadcast_peer_notification (peer,
613 * Lookup a neighbour entry in the neighbours hash map.
615 * @param pid identity of the peer to look up
616 * @return the entry, NULL if there is no existing record
618 static struct NeighbourMapEntry *
619 lookup_neighbour (const struct GNUNET_PeerIdentity *pid)
621 if (NULL == neighbours)
623 return GNUNET_CONTAINER_multipeermap_get (neighbours, pid);
628 * Test if we're connected to the given peer.
630 * @param n neighbour entry of peer to test
631 * @return #GNUNET_YES if we are connected, #GNUNET_NO if not
634 test_connected (struct NeighbourMapEntry *n)
638 return GNUNET_TRANSPORT_is_connected (n->state);
643 * Send information about a new outbound quota to our clients.
645 * @param target affected peer
646 * @param quota new quota
649 send_outbound_quota (const struct GNUNET_PeerIdentity *target,
650 struct GNUNET_BANDWIDTH_Value32NBO quota)
652 struct QuotaSetMessage q_msg;
654 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
655 "Sending outbound quota of %u Bps for peer `%s' to all clients\n",
656 ntohl (quota.value__),
657 GNUNET_i2s (target));
658 q_msg.header.size = htons (sizeof (struct QuotaSetMessage));
659 q_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA);
661 q_msg.peer = (*target);
662 GST_clients_broadcast (&q_msg.header, GNUNET_NO);
667 * We don't need a given neighbour address any more.
668 * Release its resources and give appropriate notifications
669 * to ATS and other subsystems.
671 * @param na address we are done with; @a na itself must NOT be 'free'd, only the contents!
674 free_address (struct NeighbourAddress *na)
676 if (GNUNET_YES == na->ats_active)
677 GST_validation_set_address_use (na->address,
679 if (NULL != na->address)
681 GST_ats_block_address (na->address,
683 GNUNET_HELLO_address_free (na->address);
686 na->bandwidth_in = GNUNET_BANDWIDTH_value_init (0);
687 na->bandwidth_out = GNUNET_BANDWIDTH_value_init (0);
688 na->ats_active = GNUNET_NO;
689 na->keep_alive_nonce = 0;
695 * Master task run for every neighbour. Performs all of the time-related
696 * activities (keep alive, send next message, disconnect if idle, finish
697 * clean up after disconnect).
699 * @param cls the `struct NeighbourMapEntry` for which we are running
700 * @param tc scheduler context (unused)
703 master_task (void *cls,
704 const struct GNUNET_SCHEDULER_TaskContext *tc);
708 * Set net state and state timeout for this neighbour and notify monitoring
710 * @param n the respective neighbour
711 * @param s the new state
712 * @param timeout the new timeout
715 set_state_and_timeout (struct NeighbourMapEntry *n,
716 enum GNUNET_TRANSPORT_PeerState s,
717 struct GNUNET_TIME_Absolute timeout)
719 if (GNUNET_TRANSPORT_is_connected (s) &&
720 ! GNUNET_TRANSPORT_is_connected (n->state) )
722 neighbours_connect_notification (&n->id,
723 n->primary_address.bandwidth_in,
724 n->primary_address.bandwidth_out);
725 GNUNET_STATISTICS_set (GST_stats,
726 gettext_noop ("# peers connected"),
727 ++neighbours_connected,
730 if (! GNUNET_TRANSPORT_is_connected (s) &&
731 GNUNET_TRANSPORT_is_connected (n->state) )
733 GNUNET_STATISTICS_set (GST_stats,
734 gettext_noop ("# peers connected"),
735 --neighbours_connected,
737 neighbours_disconnect_notification (&n->id);
740 if ( (timeout.abs_value_us < n->timeout.abs_value_us) &&
743 /* new timeout is earlier, reschedule master task */
744 GNUNET_SCHEDULER_cancel (n->task);
745 n->task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining (timeout),
749 n->timeout = timeout;
750 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
751 "Neighbour `%s' changed state to %s with timeout %s\n",
753 GNUNET_TRANSPORT_ps2s(s),
754 GNUNET_STRINGS_absolute_time_to_string (timeout));
755 neighbours_changed_notification (&n->id,
756 n->primary_address.address,
759 n->primary_address.bandwidth_in,
760 n->primary_address.bandwidth_out);
765 * Initialize the alternative address of a neighbour
767 * @param n the neighbour
768 * @param address address of the other peer, NULL if other peer
770 * @param session session to use (or NULL, in which case an
771 * address must be setup)
772 * @param bandwidth_in inbound quota to be used when connection is up
773 * @param bandwidth_out outbound quota to be used when connection is up
776 set_alternative_address (struct NeighbourMapEntry *n,
777 const struct GNUNET_HELLO_Address *address,
778 struct Session *session,
779 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
780 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
782 struct GNUNET_TRANSPORT_PluginFunctions *papi;
784 if (NULL == (papi = GST_plugins_find (address->transport_name)))
789 if (session == n->alternative_address.session)
791 n->alternative_address.bandwidth_in = bandwidth_in;
792 n->alternative_address.bandwidth_out = bandwidth_out;
795 if (NULL != n->alternative_address.address)
797 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
798 "Replacing existing alternative address with another one\n");
799 free_address (&n->alternative_address);
802 session = papi->get_session (papi->cls,
806 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
807 "Failed to obtain new session for peer `%s' and address '%s'\n",
808 GNUNET_i2s (&address->peer),
809 GST_plugins_a2s (address));
810 GNUNET_STATISTICS_update (GST_stats,
811 gettext_noop ("# session creation failed"),
816 GST_ats_new_session (address,
818 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
819 "Neighbour `%s' configured alternative address %s\n",
821 GST_plugins_a2s(address));
823 n->alternative_address.address = GNUNET_HELLO_address_copy (address);
824 n->alternative_address.bandwidth_in = bandwidth_in;
825 n->alternative_address.bandwidth_out = bandwidth_out;
826 n->alternative_address.session = session;
827 n->alternative_address.ats_active = GNUNET_NO;
828 n->alternative_address.keep_alive_nonce = 0;
833 * Initialize the primary address of a neighbour
835 * @param n the neighbour
836 * @param address address of the other peer, NULL if other peer
838 * @param session session to use (or NULL, in which case an
839 * address must be setup)
840 * @param bandwidth_in inbound quota to be used when connection is up
841 * @param bandwidth_out outbound quota to be used when connection is up
844 set_primary_address (struct NeighbourMapEntry *n,
845 const struct GNUNET_HELLO_Address *address,
846 struct Session *session,
847 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
848 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
850 if (session == n->primary_address.session)
852 GST_validation_set_address_use (n->primary_address.address,
854 if (n->primary_address.bandwidth_in.value__ != bandwidth_in.value__)
856 n->primary_address.bandwidth_in = bandwidth_in;
857 GST_neighbours_set_incoming_quota (&address->peer,
860 if (n->primary_address.bandwidth_out.value__ != bandwidth_out.value__)
862 n->primary_address.bandwidth_out = bandwidth_out;
863 send_outbound_quota (&address->peer,
868 if ( (NULL != n->primary_address.address) &&
869 (0 == GNUNET_HELLO_address_cmp (address,
870 n->primary_address.address)) )
878 GST_ats_block_address (address,
882 if (NULL != n->primary_address.address)
884 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
885 "Replacing existing primary address with another one\n");
886 free_address (&n->primary_address);
888 n->primary_address.address = GNUNET_HELLO_address_copy (address);
889 n->primary_address.bandwidth_in = bandwidth_in;
890 n->primary_address.bandwidth_out = bandwidth_out;
891 n->primary_address.session = session;
892 n->primary_address.keep_alive_nonce = 0;
893 /* subsystems about address use */
894 GST_validation_set_address_use (n->primary_address.address,
896 GST_neighbours_set_incoming_quota (&address->peer,
898 send_outbound_quota (&address->peer,
900 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
901 "Neighbour `%s' switched to address `%s'\n",
903 GST_plugins_a2s(address));
905 neighbours_changed_notification (&n->id,
906 n->primary_address.address,
909 n->primary_address.bandwidth_in,
910 n->primary_address.bandwidth_out);
915 * Clear the primary address of a neighbour since this address is not
916 * valid anymore and notify monitoring about it
918 * @param n the neighbour
921 unset_primary_address (struct NeighbourMapEntry *n)
923 /* Notify monitoring about change */
924 if (NULL == n->primary_address.address)
926 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
927 "Disabling primary address\n");
928 neighbours_changed_notification (&n->id,
929 n->primary_address.address,
932 GNUNET_BANDWIDTH_value_init (0),
933 GNUNET_BANDWIDTH_value_init (0));
934 free_address (&n->primary_address);
939 * Free a neighbour map entry.
941 * @param n entry to free
944 free_neighbour (struct NeighbourMapEntry *n)
946 struct MessageQueue *mq;
948 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
949 "Freeing neighbour state of peer `%s'\n",
950 GNUNET_i2s (&n->id));
951 n->is_active = NULL; /* always free'd by its own continuation! */
953 /* fail messages currently in the queue */
954 while (NULL != (mq = n->messages_head))
956 GNUNET_CONTAINER_DLL_remove (n->messages_head,
959 if (NULL != mq->cont)
960 mq->cont (mq->cont_cls,
962 mq->message_buf_size,
966 /* Mark peer as disconnected */
967 set_state_and_timeout (n,
968 GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED,
969 GNUNET_TIME_UNIT_FOREVER_ABS);
970 /* free addresses and mark as unused */
971 unset_primary_address (n);
973 if (NULL != n->alternative_address.address)
975 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
976 "Cleaning up alternative address\n");
977 free_address (&n->alternative_address);
979 GNUNET_assert (GNUNET_YES ==
980 GNUNET_CONTAINER_multipeermap_remove (neighbours,
983 /* Cancel address requests for this peer */
984 if (NULL != n->suggest_handle)
986 GNUNET_ATS_connectivity_suggest_cancel (n->suggest_handle);
987 n->suggest_handle = NULL;
990 /* Cancel the disconnect task */
991 if (NULL != n->delayed_disconnect_task)
993 GNUNET_SCHEDULER_cancel (n->delayed_disconnect_task);
994 n->delayed_disconnect_task = NULL;
997 /* Cancel the master task */
1000 GNUNET_SCHEDULER_cancel (n->task);
1003 /* free rest of memory */
1009 * Transmit a message using the current session of the given
1012 * @param n entry for the recipient
1013 * @param msgbuf buffer to transmit
1014 * @param msgbuf_size number of bytes in @a msgbuf buffer
1015 * @param priority transmission priority
1016 * @param timeout transmission timeout
1017 * @param use_keepalive_timeout #GNUNET_YES to use plugin-specific keep-alive
1018 * timeout (@a timeout is ignored in that case), #GNUNET_NO otherwise
1019 * @param cont continuation to call when finished (can be NULL)
1020 * @param cont_cls closure for @a cont
1021 * @return timeout (copy of @a timeout or a calculated one if
1022 * @a use_keepalive_timeout is #GNUNET_YES.
1024 static struct GNUNET_TIME_Relative
1025 send_with_session (struct NeighbourMapEntry *n,
1029 struct GNUNET_TIME_Relative timeout,
1030 unsigned int use_keepalive_timeout,
1031 GNUNET_TRANSPORT_TransmitContinuation cont,
1034 struct GNUNET_TRANSPORT_PluginFunctions *papi;
1035 struct GNUNET_TIME_Relative result = GNUNET_TIME_UNIT_FOREVER_REL;
1037 GNUNET_assert (NULL != n->primary_address.session);
1038 if ( ((NULL == (papi = GST_plugins_find (n->primary_address.address->transport_name)) ||
1039 (-1 == papi->send (papi->cls,
1040 n->primary_address.session,
1044 (result = (GNUNET_NO == use_keepalive_timeout) ? timeout :
1045 GNUNET_TIME_relative_divide (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
1046 papi->query_keepalive_factor (papi->cls))),
1055 GST_neighbours_notify_data_sent (n->primary_address.address,
1056 n->primary_address.session,
1058 GNUNET_break (NULL != papi);
1064 * Function called when the 'DISCONNECT' message has been sent by the
1065 * plugin. Frees the neighbour --- if the entry still exists.
1068 * @param target identity of the neighbour that was disconnected
1069 * @param result #GNUNET_OK if the disconnect got out successfully
1070 * @param payload bytes payload
1071 * @param physical bytes on wire
1074 send_disconnect_cont (void *cls,
1075 const struct GNUNET_PeerIdentity *target,
1080 struct NeighbourMapEntry *n;
1082 n = lookup_neighbour (target);
1084 return; /* already gone */
1085 if (GNUNET_TRANSPORT_PS_DISCONNECT != n->state)
1086 return; /* have created a fresh entry since */
1087 if (NULL != n->task)
1088 GNUNET_SCHEDULER_cancel (n->task);
1089 n->task = GNUNET_SCHEDULER_add_now (&master_task, n);
1094 * Transmit a DISCONNECT message to the other peer.
1096 * @param n neighbour to send DISCONNECT message.
1099 send_disconnect (struct NeighbourMapEntry *n)
1101 struct SessionDisconnectMessage disconnect_msg;
1103 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1104 "Sending DISCONNECT message to peer `%4s'\n",
1105 GNUNET_i2s (&n->id));
1106 disconnect_msg.header.size = htons (sizeof (struct SessionDisconnectMessage));
1107 disconnect_msg.header.type =
1108 htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT);
1109 disconnect_msg.reserved = htonl (0);
1110 disconnect_msg.purpose.size =
1111 htonl (sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
1112 sizeof (struct GNUNET_CRYPTO_EddsaPublicKey) +
1113 sizeof (struct GNUNET_TIME_AbsoluteNBO));
1114 disconnect_msg.purpose.purpose =
1115 htonl (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT);
1116 disconnect_msg.timestamp =
1117 GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
1118 disconnect_msg.public_key = GST_my_identity.public_key;
1119 GNUNET_assert (GNUNET_OK ==
1120 GNUNET_CRYPTO_eddsa_sign (GST_my_private_key,
1121 &disconnect_msg.purpose,
1122 &disconnect_msg.signature));
1124 (void) send_with_session (n,
1126 sizeof (disconnect_msg),
1128 GNUNET_TIME_UNIT_FOREVER_REL,
1130 &send_disconnect_cont,
1132 GNUNET_STATISTICS_update (GST_stats,
1133 gettext_noop ("# DISCONNECT messages sent"),
1140 * Disconnect from the given neighbour, clean up the record.
1142 * @param n neighbour to disconnect from
1145 disconnect_neighbour (struct NeighbourMapEntry *n)
1147 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1148 "Disconnecting from peer %s in state %s\n",
1149 GNUNET_i2s (&n->id),
1150 GNUNET_TRANSPORT_ps2s (n->state));
1151 /* depending on state, notify neighbour and/or upper layers of this peer
1155 case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
1156 case GNUNET_TRANSPORT_PS_INIT_ATS:
1157 /* other peer is completely unaware of us, no need to send DISCONNECT */
1160 case GNUNET_TRANSPORT_PS_SYN_SENT:
1161 send_disconnect (n);
1162 set_state_and_timeout (n,
1163 GNUNET_TRANSPORT_PS_DISCONNECT,
1164 GNUNET_TIME_UNIT_FOREVER_ABS);
1166 case GNUNET_TRANSPORT_PS_SYN_RECV_ATS:
1167 /* we never ACK'ed the other peer's request, no need to send DISCONNECT */
1170 case GNUNET_TRANSPORT_PS_SYN_RECV_ACK:
1171 /* we DID ACK the other peer's request, must send DISCONNECT */
1172 send_disconnect (n);
1173 set_state_and_timeout (n,
1174 GNUNET_TRANSPORT_PS_DISCONNECT,
1175 GNUNET_TIME_UNIT_FOREVER_ABS);
1177 case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT:
1178 case GNUNET_TRANSPORT_PS_CONNECTED:
1179 case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
1180 /* we are currently connected, need to send disconnect and do
1181 internal notifications and update statistics */
1182 send_disconnect (n);
1183 set_state_and_timeout (n,
1184 GNUNET_TRANSPORT_PS_DISCONNECT,
1185 GNUNET_TIME_UNIT_FOREVER_ABS);
1187 case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
1188 /* Disconnecting while waiting for an ATS address to reconnect,
1189 * cannot send DISCONNECT */
1192 case GNUNET_TRANSPORT_PS_DISCONNECT:
1193 /* already disconnected, ignore */
1195 case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
1196 /* already cleaned up, how did we get here!? */
1200 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1201 "Unhandled state `%s'\n",
1202 GNUNET_TRANSPORT_ps2s (n->state));
1206 /* schedule timeout to clean up */
1207 if (NULL != n->task)
1208 GNUNET_SCHEDULER_cancel (n->task);
1209 n->task = GNUNET_SCHEDULER_add_delayed (DISCONNECT_SENT_TIMEOUT,
1216 * We're done with our transmission attempt, continue processing.
1218 * @param cls the `struct MessageQueue` of the message
1219 * @param receiver intended receiver
1220 * @param success whether it worked or not
1221 * @param size_payload bytes payload sent
1222 * @param physical bytes sent on wire
1225 transmit_send_continuation (void *cls,
1226 const struct GNUNET_PeerIdentity *receiver,
1227 int success, size_t size_payload, size_t physical)
1229 struct MessageQueue *mq = cls;
1230 struct NeighbourMapEntry *n;
1232 if (NULL == (n = lookup_neighbour (receiver)))
1235 return; /* disconnect or other error while transmitting, can happen */
1237 if (n->is_active == mq)
1239 /* this is still "our" neighbour, remove us from its queue
1240 and allow it to send the next message now */
1241 n->is_active = NULL;
1242 if (NULL != n->task)
1243 GNUNET_SCHEDULER_cancel (n->task);
1244 n->task = GNUNET_SCHEDULER_add_now (&master_task, n);
1246 if (bytes_in_send_queue < mq->message_buf_size)
1248 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1249 "Bytes_in_send_queue `%u', Message_size %u, result: %s, payload %u, on wire %u\n",
1250 bytes_in_send_queue,
1251 mq->message_buf_size,
1252 (GNUNET_OK == success) ? "OK" : "FAIL",
1259 GNUNET_break (size_payload == mq->message_buf_size);
1260 bytes_in_send_queue -= mq->message_buf_size;
1261 GNUNET_STATISTICS_set (GST_stats,
1263 ("# bytes in message queue for other peers"),
1264 bytes_in_send_queue, GNUNET_NO);
1265 if (GNUNET_OK == success)
1266 GNUNET_STATISTICS_update (GST_stats,
1268 ("# messages transmitted to other peers"),
1271 GNUNET_STATISTICS_update (GST_stats,
1273 ("# transmission failures for messages to other peers"),
1275 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1276 "Sending message to `%s' of type %u with %u bytes was a %s\n",
1277 GNUNET_i2s (receiver),
1278 ntohs (((struct GNUNET_MessageHeader *) mq->message_buf)->type),
1279 mq->message_buf_size,
1280 (success == GNUNET_OK) ? "success" : "FAILURE");
1281 if (NULL != mq->cont)
1282 mq->cont (mq->cont_cls, success, size_payload, physical);
1288 * Check the message list for the given neighbour and if we can
1289 * send a message, do so. This function should only be called
1290 * if the connection is at least generally ready for transmission.
1291 * While we will only send one message at a time, no bandwidth
1292 * quota management is performed here. If a message was given to
1293 * the plugin, the continuation will automatically re-schedule
1294 * the 'master' task once the next message might be transmitted.
1296 * @param n target peer for which to transmit
1299 try_transmission_to_peer (struct NeighbourMapEntry *n)
1301 struct MessageQueue *mq;
1302 struct GNUNET_TIME_Relative timeout;
1304 if (NULL == n->primary_address.address)
1306 /* no address, why are we here? */
1310 if ((0 == n->primary_address.address->address_length) &&
1311 (NULL == n->primary_address.session))
1313 /* no address, why are we here? */
1317 if (NULL != n->is_active)
1319 /* transmission already pending */
1323 /* timeout messages from the queue that are past their due date */
1324 while (NULL != (mq = n->messages_head))
1326 timeout = GNUNET_TIME_absolute_get_remaining (mq->timeout);
1327 if (timeout.rel_value_us > 0)
1329 GNUNET_STATISTICS_update (GST_stats,
1331 ("# messages timed out while in transport queue"),
1333 GNUNET_CONTAINER_DLL_remove (n->messages_head,
1337 transmit_send_continuation (mq,
1340 mq->message_buf_size,
1344 return; /* no more messages */
1345 GNUNET_CONTAINER_DLL_remove (n->messages_head,
1350 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1351 "Giving message with %u bytes to plugin session %p\n",
1352 mq->message_buf_size,
1353 n->primary_address.session);
1354 (void) send_with_session (n,
1356 mq->message_buf_size,
1360 &transmit_send_continuation,
1366 * Send keepalive message to the neighbour. Must only be called
1367 * if we are on 'connected' state or while trying to switch addresses.
1368 * Will internally determine if a keepalive is truly needed (so can
1369 * always be called).
1371 * @param n neighbour that went idle and needs a keepalive
1374 send_keepalive (struct NeighbourMapEntry *n)
1376 struct SessionKeepAliveMessage m;
1377 struct GNUNET_TIME_Relative timeout;
1380 GNUNET_assert ((GNUNET_TRANSPORT_PS_CONNECTED == n->state) ||
1381 (GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT == n->state));
1382 if (GNUNET_TIME_absolute_get_remaining (n->keep_alive_time).rel_value_us > 0)
1383 return; /* no keepalive needed at this time */
1385 nonce = 0; /* 0 indicates 'not set' */
1387 nonce = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
1389 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1390 "Sending keep alive to peer `%s' with nonce %u\n",
1391 GNUNET_i2s (&n->id),
1393 m.header.size = htons (sizeof (struct SessionKeepAliveMessage));
1394 m.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE);
1395 m.nonce = htonl (nonce);
1397 timeout = send_with_session (n,
1400 UINT32_MAX /* priority */,
1401 GNUNET_TIME_UNIT_FOREVER_REL,
1404 GNUNET_STATISTICS_update (GST_stats,
1405 gettext_noop ("# keepalives sent"),
1408 n->primary_address.keep_alive_nonce = nonce;
1409 n->expect_latency_response = GNUNET_YES;
1410 n->last_keep_alive_time = GNUNET_TIME_absolute_get ();
1411 n->keep_alive_time = GNUNET_TIME_relative_to_absolute (timeout);
1416 * Keep the connection to the given neighbour alive longer,
1417 * we received a KEEPALIVE (or equivalent); send a response.
1419 * @param neighbour neighbour to keep alive (by sending keep alive response)
1420 * @param m the keep alive message containing the nonce to respond to
1423 GST_neighbours_keepalive (const struct GNUNET_PeerIdentity *neighbour,
1424 const struct GNUNET_MessageHeader *m)
1426 struct NeighbourMapEntry *n;
1427 const struct SessionKeepAliveMessage *msg_in;
1428 struct SessionKeepAliveMessage msg;
1430 if (sizeof (struct SessionKeepAliveMessage) != ntohs (m->size))
1433 msg_in = (struct SessionKeepAliveMessage *) m;
1434 if (NULL == (n = lookup_neighbour (neighbour)))
1436 GNUNET_STATISTICS_update (GST_stats,
1438 ("# KEEPALIVE messages discarded (peer unknown)"),
1442 if (NULL == n->primary_address.session)
1444 GNUNET_STATISTICS_update (GST_stats,
1446 ("# KEEPALIVE messages discarded (no session)"),
1451 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1452 "Received keep alive request from peer `%s' with nonce %u\n",
1453 GNUNET_i2s (&n->id), ntohl (msg_in->nonce));
1455 /* send reply to allow neighbour to measure latency */
1456 msg.header.size = htons (sizeof (struct SessionKeepAliveMessage));
1457 msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE_RESPONSE);
1458 msg.nonce = msg_in->nonce;
1459 (void) send_with_session (n,
1461 sizeof (struct SessionKeepAliveMessage),
1462 UINT32_MAX /* priority */,
1463 GNUNET_TIME_UNIT_FOREVER_REL,
1470 * We received a KEEP_ALIVE_RESPONSE message and use this to calculate
1471 * latency to this peer. Pass the updated information (existing ats
1472 * plus calculated latency) to ATS.
1474 * @param neighbour neighbour to keep alive
1475 * @param m the message containing the keep alive response
1478 GST_neighbours_keepalive_response (const struct GNUNET_PeerIdentity *neighbour,
1479 const struct GNUNET_MessageHeader *m)
1481 struct NeighbourMapEntry *n;
1482 const struct SessionKeepAliveMessage *msg;
1483 struct GNUNET_TRANSPORT_PluginFunctions *papi;
1484 struct GNUNET_ATS_Information ats;
1485 struct GNUNET_TIME_Relative latency;
1487 if (sizeof (struct SessionKeepAliveMessage) != ntohs (m->size))
1490 msg = (const struct SessionKeepAliveMessage *) m;
1491 if (NULL == (n = lookup_neighbour (neighbour)))
1493 GNUNET_STATISTICS_update (GST_stats,
1495 ("# KEEPALIVE_RESPONSE messages discarded (not connected)"),
1499 if ( (GNUNET_TRANSPORT_PS_CONNECTED != n->state) ||
1500 (GNUNET_YES != n->expect_latency_response) )
1502 GNUNET_STATISTICS_update (GST_stats,
1504 ("# KEEPALIVE_RESPONSE messages discarded (not expected)"),
1508 if (NULL == n->primary_address.address)
1510 GNUNET_STATISTICS_update (GST_stats,
1512 ("# KEEPALIVE_RESPONSE messages discarded (address changed)"),
1516 if (n->primary_address.keep_alive_nonce != ntohl (msg->nonce))
1518 GNUNET_STATISTICS_update (GST_stats,
1520 ("# KEEPALIVE_RESPONSE messages discarded (wrong nonce)"),
1526 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1527 "Received keep alive response from peer `%s' for session %p\n",
1528 GNUNET_i2s (&n->id), n->primary_address.session);
1532 /* Update session timeout here */
1533 if (NULL != (papi = GST_plugins_find (n->primary_address.address->transport_name)))
1535 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1536 "Updating session for peer `%s' for session %p\n",
1537 GNUNET_i2s (&n->id), n->primary_address.session);
1538 papi->update_session_timeout (papi->cls, &n->id, n->primary_address.session);
1545 n->primary_address.keep_alive_nonce = 0;
1546 n->expect_latency_response = GNUNET_NO;
1547 set_state_and_timeout (n,
1549 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT));
1551 latency = GNUNET_TIME_absolute_get_duration (n->last_keep_alive_time);
1552 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1553 "Latency for peer `%s' is %s\n",
1554 GNUNET_i2s (&n->id),
1555 GNUNET_STRINGS_relative_time_to_string (latency,
1557 /* append latency */
1558 ats.type = htonl (GNUNET_ATS_QUALITY_NET_DELAY);
1559 ats.value = htonl ( (latency.rel_value_us > UINT32_MAX)
1561 : (uint32_t) latency.rel_value_us );
1562 GST_ats_update_metrics (n->primary_address.address,
1563 n->primary_address.session,
1570 * We have received a message from the given sender. How long should
1571 * we delay before receiving more? (Also used to keep the peer marked
1574 * @param sender sender of the message
1575 * @param size size of the message
1576 * @param do_forward set to #GNUNET_YES if the message should be forwarded to clients
1577 * #GNUNET_NO if the neighbour is not connected or violates the quota,
1578 * #GNUNET_SYSERR if the connection is not fully up yet
1579 * @return how long to wait before reading more from this sender
1581 struct GNUNET_TIME_Relative
1582 GST_neighbours_calculate_receive_delay (const struct GNUNET_PeerIdentity
1583 *sender, ssize_t size, int *do_forward)
1585 struct NeighbourMapEntry *n;
1586 struct GNUNET_TIME_Relative ret;
1588 if (NULL == neighbours)
1590 *do_forward = GNUNET_NO;
1591 return GNUNET_TIME_UNIT_FOREVER_REL; /* This can happen during shutdown */
1593 if (NULL == (n = lookup_neighbour (sender)))
1595 GST_neighbours_try_connect (sender);
1596 if (NULL == (n = lookup_neighbour (sender)))
1598 GNUNET_STATISTICS_update (GST_stats,
1600 ("# messages discarded due to lack of neighbour record"),
1602 *do_forward = GNUNET_NO;
1603 return GNUNET_TIME_UNIT_ZERO;
1606 if (! test_connected (n))
1608 *do_forward = GNUNET_SYSERR;
1609 return GNUNET_TIME_UNIT_ZERO;
1611 if (GNUNET_YES == GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, size))
1613 n->quota_violation_count++;
1614 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1615 "Bandwidth quota (%u b/s) violation detected (total of %u).\n",
1616 n->in_tracker.available_bytes_per_s__,
1617 n->quota_violation_count);
1618 /* Discount 32k per violation */
1619 GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, -32 * 1024);
1623 if (n->quota_violation_count > 0)
1625 /* try to add 32k back */
1626 GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, 32 * 1024);
1627 n->quota_violation_count--;
1630 if (n->quota_violation_count > QUOTA_VIOLATION_DROP_THRESHOLD)
1632 GNUNET_STATISTICS_update (GST_stats,
1634 ("# bandwidth quota violations by other peers"),
1636 *do_forward = GNUNET_NO;
1637 return GNUNET_CONSTANTS_QUOTA_VIOLATION_TIMEOUT;
1639 *do_forward = GNUNET_YES;
1640 ret = GNUNET_BANDWIDTH_tracker_get_delay (&n->in_tracker, 32 * 1024);
1641 if (ret.rel_value_us > 0)
1643 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1644 "Throttling read (%lld bytes excess at %u b/s), waiting %s before reading more.\n",
1645 (long long) n->in_tracker.consumption_since_last_update__,
1646 (unsigned int) n->in_tracker.available_bytes_per_s__,
1647 GNUNET_STRINGS_relative_time_to_string (ret, GNUNET_YES));
1648 GNUNET_STATISTICS_update (GST_stats,
1649 gettext_noop ("# ms throttling suggested"),
1650 (int64_t) ret.rel_value_us / 1000LL,
1658 * Transmit a message to the given target using the active connection.
1660 * @param target destination
1661 * @param msg message to send
1662 * @param msg_size number of bytes in msg
1663 * @param timeout when to fail with timeout
1664 * @param cont function to call when done
1665 * @param cont_cls closure for @a cont
1668 GST_neighbours_send (const struct GNUNET_PeerIdentity *target,
1671 struct GNUNET_TIME_Relative timeout,
1672 GST_NeighbourSendContinuation cont,
1675 struct NeighbourMapEntry *n;
1676 struct MessageQueue *mq;
1678 /* All ove these cases should never happen; they are all API violations.
1679 But we check anyway, just to be sure. */
1680 if (NULL == (n = lookup_neighbour (target)))
1690 if (GNUNET_YES != test_connected (n))
1700 bytes_in_send_queue += msg_size;
1701 GNUNET_STATISTICS_set (GST_stats,
1703 ("# bytes in message queue for other peers"),
1704 bytes_in_send_queue, GNUNET_NO);
1705 mq = GNUNET_malloc (sizeof (struct MessageQueue) + msg_size);
1707 mq->cont_cls = cont_cls;
1708 memcpy (&mq[1], msg, msg_size);
1709 mq->message_buf = (const char *) &mq[1];
1710 mq->message_buf_size = msg_size;
1711 mq->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1713 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1714 "Enqueueing %u bytes to send to peer %s\n",
1716 GNUNET_i2s (target));
1717 GNUNET_CONTAINER_DLL_insert_tail (n->messages_head,
1720 if (NULL != n->task)
1721 GNUNET_SCHEDULER_cancel (n->task);
1722 n->task = GNUNET_SCHEDULER_add_now (&master_task, n);
1727 * Continuation called from our attempt to transmitted our
1728 * #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN to the specified @a
1729 * target. Continue processing based on the @a result. Specifically,
1730 * if we failed to transmit, discard the address we used.
1733 * @param target which peer received the transmission
1734 * @param result #GNUNET_OK if sending worked
1735 * @param size_payload how many bytes of payload were sent (ignored)
1736 * @param size_on_wire how much bandwidth was consumed on the wire (ignored)
1739 send_session_syn_cont (void *cls,
1740 const struct GNUNET_PeerIdentity *target,
1742 size_t size_payload,
1743 size_t size_on_wire)
1745 struct NeighbourMapEntry *n;
1747 n = lookup_neighbour (target);
1750 /* SYN continuation was called after neighbor was freed,
1751 * for example due to a time out for the state or the session
1752 * used was already terminated: nothing to do here... */
1756 if ( (GNUNET_TRANSPORT_PS_SYN_SENT != n->state) &&
1757 (GNUNET_TRANSPORT_PS_RECONNECT_SENT != n->state) &&
1758 (GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT != n->state))
1760 /* SYN continuation was called after neighbor changed state,
1761 * for example due to a time out for the state or the session
1762 * used was already terminated: nothing to do here... */
1765 if (GNUNET_OK == result)
1768 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1769 _("Failed to send SYN message to peer `%s'\n"),
1770 GNUNET_i2s (target));
1772 case GNUNET_TRANSPORT_PS_SYN_SENT:
1773 /* Remove address and request an additional one */
1774 unset_primary_address (n);
1775 set_state_and_timeout (n,
1776 GNUNET_TRANSPORT_PS_INIT_ATS,
1777 GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT));
1779 case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
1780 /* Remove address and request an additional one */
1781 unset_primary_address (n);
1782 set_state_and_timeout (n,
1783 GNUNET_TRANSPORT_PS_RECONNECT_ATS,
1784 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
1786 case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT:
1787 /* Remove address and request and go back to primary address */
1788 GNUNET_STATISTICS_update (GST_stats,
1789 gettext_noop ("# Failed attempts to switch addresses (failed to send SYN CONT)"),
1792 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1793 "Switch failed, cleaning up alternative address\n");
1794 free_address (&n->alternative_address);
1795 set_state_and_timeout (n,
1796 GNUNET_TRANSPORT_PS_CONNECTED,
1797 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
1800 disconnect_neighbour (n);
1807 * Send a SYN message via the given address.
1809 * @param na address to use
1812 send_syn (struct NeighbourAddress *na)
1814 struct GNUNET_TRANSPORT_PluginFunctions *papi;
1815 struct TransportSynMessage connect_msg;
1816 struct NeighbourMapEntry *n;
1818 GNUNET_assert (NULL != na->session);
1819 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1820 "Sending SYN message to peer `%s' at %s\n",
1821 GNUNET_i2s (&na->address->peer),
1822 GST_plugins_a2s (na->address));
1824 papi = GST_plugins_find (na->address->transport_name);
1825 GNUNET_assert (NULL != papi);
1826 GNUNET_STATISTICS_update (GST_stats,
1828 ("# SYN messages sent"),
1830 na->connect_timestamp = GNUNET_TIME_absolute_get ();
1831 connect_msg.header.size = htons (sizeof (struct TransportSynMessage));
1832 connect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN);
1833 connect_msg.reserved = htonl (0);
1834 connect_msg.timestamp = GNUNET_TIME_absolute_hton (na->connect_timestamp);
1836 papi->send (papi->cls,
1838 (const char *) &connect_msg,
1839 sizeof (struct TransportSynMessage),
1841 SETUP_CONNECTION_TIMEOUT,
1842 &send_session_syn_cont, NULL))
1844 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1845 _("Failed to transmit SYN message to %s\n"),
1846 GST_plugins_a2s (na->address));
1847 n = lookup_neighbour (&na->address->peer);
1854 case GNUNET_TRANSPORT_PS_SYN_SENT:
1855 /* Remove address and request and additional one */
1856 GNUNET_assert (na == &n->primary_address);
1857 unset_primary_address (n);
1858 set_state_and_timeout (n,
1859 GNUNET_TRANSPORT_PS_INIT_ATS,
1860 GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT));
1861 /* Hard failure to send the SYN message with this address:
1862 Destroy address and session */
1864 case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
1865 /* Remove address and request an additional one */
1866 GNUNET_assert (na == &n->primary_address);
1867 unset_primary_address (n);
1868 set_state_and_timeout (n,
1869 GNUNET_TRANSPORT_PS_RECONNECT_ATS,
1870 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
1872 case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT:
1873 GNUNET_assert (na == &n->alternative_address);
1874 GNUNET_STATISTICS_update (GST_stats,
1875 gettext_noop ("# Failed attempts to switch addresses (failed to send SYN)"),
1878 /* Remove address and request an additional one */
1879 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1880 "Switch failed, cleaning up alternative address\n");
1881 free_address (&n->alternative_address);
1882 set_state_and_timeout (n,
1883 GNUNET_TRANSPORT_PS_CONNECTED,
1884 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
1888 disconnect_neighbour (n);
1893 GST_neighbours_notify_data_sent (na->address,
1895 sizeof (struct TransportSynMessage));
1900 * Continuation called from our attempt to transmitted our
1901 * #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN_ACK to the specified @a
1902 * target. Continue processing based on the @a result. Specifically,
1903 * if we failed to transmit, discard the address we used.
1906 * @param target which peer received the transmission
1907 * @param result #GNUNET_OK if sending worked
1908 * @param size_payload how many bytes of payload were sent (ignored)
1909 * @param size_on_wire how much bandwidth was consumed on the wire (ignored)
1912 send_session_syn_ack_cont (void *cls,
1913 const struct GNUNET_PeerIdentity *target,
1915 size_t size_payload,
1916 size_t size_on_wire)
1918 struct NeighbourMapEntry *n;
1920 n = lookup_neighbour (target);
1923 /* SYN_ACK continuation was called after neighbor was freed,
1924 * for example due to a time out for the state or the session
1925 * used was already terminated: nothing to do here... */
1929 if (GNUNET_TRANSPORT_PS_SYN_RECV_ACK != n->state)
1931 /* SYN_ACK continuation was called after neighbor changed state,
1932 * for example due to a time out for the state or the session
1933 * used was already terminated: nothing to do here... */
1936 if (GNUNET_OK == result)
1939 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1940 _("Failed to send SYN_ACK message to peer `%s' using address `%s'\n"),
1941 GNUNET_i2s (target),
1942 GST_plugins_a2s (n->primary_address.address));
1944 /* Remove address and request and additional one */
1945 /* FIXME: what if the neighbour's primary address
1946 changed in the meantime? Might want to instead
1947 pass "something" around in closure to be sure. */
1948 unset_primary_address (n);
1949 n->ack_state = ACK_SEND_SYN_ACK;
1950 set_state_and_timeout (n,
1951 GNUNET_TRANSPORT_PS_SYN_RECV_ATS,
1952 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
1957 * Send a SYN_ACK message via the given address.
1959 * @param na address and session to use
1960 * @param timestamp timestamp to use for the ACK message
1961 * @return #GNUNET_SYSERR if sending immediately failed, #GNUNET_OK otherwise
1964 send_syn_ack_message (struct NeighbourAddress *na,
1965 struct GNUNET_TIME_Absolute timestamp)
1967 const struct GNUNET_HELLO_Address *address = na->address;
1968 struct Session *session = na->session;
1969 struct GNUNET_TRANSPORT_PluginFunctions *papi;
1970 struct TransportSynMessage connect_msg;
1971 struct NeighbourMapEntry *n;
1973 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1974 "Sending SYN_ACK to peer `%s'\n",
1975 GNUNET_i2s (&address->peer));
1977 if (NULL == (papi = GST_plugins_find (address->transport_name)))
1982 if (NULL == session)
1983 session = papi->get_session (papi->cls,
1985 if (NULL == session)
1990 GST_ats_new_session (address,
1992 GNUNET_STATISTICS_update (GST_stats,
1994 ("# SYN_ACK messages sent"),
1996 connect_msg.header.size = htons (sizeof (struct TransportSynMessage));
1997 connect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN_ACK);
1998 connect_msg.reserved = htonl (0);
1999 connect_msg.timestamp = GNUNET_TIME_absolute_hton (timestamp);
2001 if (GNUNET_SYSERR ==
2002 papi->send (papi->cls,
2004 (const char *) &connect_msg,
2005 sizeof (struct TransportSynMessage),
2007 GNUNET_TIME_UNIT_FOREVER_REL,
2008 &send_session_syn_ack_cont, NULL))
2010 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2011 _("Failed to transmit SYN_ACK message to %s\n"),
2012 GST_plugins_a2s (address));
2014 n = lookup_neighbour (&address->peer);
2020 /* Remove address and request and additional one */
2021 unset_primary_address (n);
2022 n->ack_state = ACK_SEND_SYN_ACK;
2023 set_state_and_timeout (n,
2024 GNUNET_TRANSPORT_PS_SYN_RECV_ATS,
2025 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
2032 * Function called by the bandwidth tracker for a peer whenever
2033 * the tracker's state changed such that we need to recalculate
2034 * the delay for flow control. We calculate the latest delay
2035 * and inform the plugin (if applicable).
2037 * @param cls the `struct NeighbourMapEntry` to update calculations for
2040 inbound_bw_tracker_update (void *cls)
2042 struct NeighbourMapEntry *n = cls;
2043 struct GNUNET_TRANSPORT_PluginFunctions *papi;
2044 struct GNUNET_TIME_Relative delay;
2047 if (NULL == n->primary_address.address)
2048 return; /* not active, ignore */
2049 papi = GST_plugins_find (n->primary_address.address->transport_name);
2050 GNUNET_assert (NULL != papi);
2051 if (NULL == papi->update_inbound_delay)
2053 delay = GST_neighbours_calculate_receive_delay (&n->id,
2056 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2057 "New inbound delay for peer `%s' is %llu ms\n",
2058 GNUNET_i2s (&n->id),
2059 delay.rel_value_us / 1000);
2060 papi->update_inbound_delay (papi->cls,
2062 n->primary_address.session,
2068 * Create a fresh entry in the neighbour map for the given peer
2070 * @param peer peer to create an entry for
2071 * @return new neighbour map entry
2073 static struct NeighbourMapEntry *
2074 setup_neighbour (const struct GNUNET_PeerIdentity *peer)
2076 struct NeighbourMapEntry *n;
2078 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2079 "Creating new neighbour entry for `%s'\n",
2081 n = GNUNET_new (struct NeighbourMapEntry);
2083 n->ack_state = ACK_UNDEFINED;
2084 n->last_util_transmission = GNUNET_TIME_absolute_get();
2085 GNUNET_BANDWIDTH_tracker_init (&n->in_tracker,
2086 &inbound_bw_tracker_update,
2088 GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
2089 MAX_BANDWIDTH_CARRY_S);
2090 n->task = GNUNET_SCHEDULER_add_now (&master_task, n);
2091 set_state_and_timeout (n,
2092 GNUNET_TRANSPORT_PS_NOT_CONNECTED,
2093 GNUNET_TIME_UNIT_FOREVER_ABS);
2094 GNUNET_assert (GNUNET_OK ==
2095 GNUNET_CONTAINER_multipeermap_put (neighbours,
2097 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2098 n->suggest_handle = GNUNET_ATS_connectivity_suggest (GST_ats_connect,
2106 * Entry in a DLL we use to keep track of pending blacklist checks.
2108 struct BlacklistCheckSwitchContext
2113 struct BlacklistCheckSwitchContext *prev;
2118 struct BlacklistCheckSwitchContext *next;
2121 * Handle to the blacklist check we are performing.
2123 struct GST_BlacklistCheck *blc;
2126 * Address we are asking the blacklist subsystem about.
2128 struct GNUNET_HELLO_Address *address;
2131 * Session we should use in conjunction with @e address, can be NULL.
2133 struct Session *session;
2136 * Inbound bandwidth that was assigned to @e address.
2138 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in;
2141 * Outbound bandwidth that was assigned to @e address.
2143 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out;
2148 * Black list check result for try_connect call
2149 * If connection to the peer is allowed request adddress and
2151 * @param cls blc_ctx bl context
2152 * @param peer the peer
2153 * @param result the result
2156 try_connect_bl_check_cont (void *cls,
2157 const struct GNUNET_PeerIdentity *peer,
2160 struct BlacklistCheckSwitchContext *blc_ctx = cls;
2161 struct NeighbourMapEntry *n;
2163 GNUNET_CONTAINER_DLL_remove (pending_bc_head,
2166 GNUNET_free (blc_ctx);
2167 if (GNUNET_OK != result)
2169 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2170 _("Blacklisting disapproved to connect to peer `%s'\n"),
2175 /* Setup a new neighbour */
2176 if (NULL != lookup_neighbour(peer))
2177 return; /* The neighbor was created in the meantime while waited for BL clients */
2179 n = setup_neighbour (peer);
2181 /* Request address suggestions for this peer */
2182 set_state_and_timeout (n,
2183 GNUNET_TRANSPORT_PS_INIT_ATS,
2184 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
2189 * Try to create a connection to the given target (eventually).
2191 * @param target peer to try to connect to
2194 GST_neighbours_try_connect (const struct GNUNET_PeerIdentity *target)
2196 struct NeighbourMapEntry *n;
2197 struct GST_BlacklistCheck *blc;
2198 struct BlacklistCheckSwitchContext *blc_ctx;
2200 if (NULL == neighbours)
2202 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2203 "Asked to connect to peer `%s' during shutdown\n",
2204 GNUNET_i2s (target));
2205 return; /* during shutdown, do nothing */
2207 n = lookup_neighbour (target);
2208 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2209 "Asked to connect to peer `%s' (state: %s)\n",
2210 GNUNET_i2s (target),
2211 (NULL != n) ? GNUNET_TRANSPORT_ps2s(n->state) : "NEW PEER");
2216 case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
2217 /* this should not be possible */
2221 case GNUNET_TRANSPORT_PS_INIT_ATS:
2222 case GNUNET_TRANSPORT_PS_SYN_SENT:
2223 case GNUNET_TRANSPORT_PS_SYN_RECV_ATS:
2224 case GNUNET_TRANSPORT_PS_SYN_RECV_ACK:
2225 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2226 "Ignoring request to try to connect to `%s', already trying!\n",
2227 GNUNET_i2s (target));
2228 return; /* already trying */
2229 case GNUNET_TRANSPORT_PS_CONNECTED:
2230 case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
2231 case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
2232 case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT:
2233 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2234 "Ignoring request to try to connect, already connected to `%s'!\n",
2235 GNUNET_i2s (target));
2236 return; /* already connected */
2237 case GNUNET_TRANSPORT_PS_DISCONNECT:
2238 /* get rid of remains, ready to re-try immediately */
2241 case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
2242 /* should not be possible */
2246 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2247 "Unhandled state `%s'\n",
2248 GNUNET_TRANSPORT_ps2s (n->state));
2255 /* Do blacklist check if connecting to this peer is allowed */
2256 blc_ctx = GNUNET_new (struct BlacklistCheckSwitchContext);
2257 GNUNET_CONTAINER_DLL_insert (pending_bc_head,
2262 (blc = GST_blacklist_test_allowed (target,
2264 &try_connect_bl_check_cont,
2273 * We received a 'SYN' message from the other peer.
2274 * Consider switching to it.
2276 * @param message possibly a 'struct TransportSynMessage' (check format)
2277 * @param peer identity of the peer to switch the address for
2278 * @return #GNUNET_OK if the message was fine, #GNUNET_SYSERR on serious error
2281 GST_neighbours_handle_session_syn (const struct GNUNET_MessageHeader *message,
2282 const struct GNUNET_PeerIdentity *peer)
2284 const struct TransportSynMessage *scm;
2285 struct NeighbourMapEntry *n;
2286 struct GNUNET_TIME_Absolute ts;
2288 if (ntohs (message->size) != sizeof (struct TransportSynMessage))
2290 GNUNET_break_op (0);
2291 return GNUNET_SYSERR;
2293 GNUNET_STATISTICS_update (GST_stats,
2295 ("# SYN messages received"),
2297 if (NULL == neighbours)
2299 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2300 _("SYN request from peer `%s' ignored due impending shutdown\n"),
2302 return GNUNET_OK; /* we're shutting down */
2304 scm = (const struct TransportSynMessage *) message;
2305 GNUNET_break_op (0 == ntohl (scm->reserved));
2306 ts = GNUNET_TIME_absolute_ntoh (scm->timestamp);
2307 n = lookup_neighbour (peer);
2310 /* This is a new neighbour and set to not connected */
2311 n = setup_neighbour (peer);
2314 /* Remember this SYN message in neighbour */
2315 n->ack_state = ACK_SEND_SYN_ACK;
2316 n->connect_ack_timestamp = ts;
2318 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2319 "Received SYN for peer `%s' in state %s/%s\n",
2321 GNUNET_TRANSPORT_ps2s (n->state),
2322 print_ack_state (n->ack_state));
2326 case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
2327 /* Request an address from ATS to send SYN_ACK to this peer */
2328 set_state_and_timeout (n,
2329 GNUNET_TRANSPORT_PS_SYN_RECV_ATS,
2330 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
2332 case GNUNET_TRANSPORT_PS_INIT_ATS:
2333 /* SYN message takes priority over us asking ATS for address:
2334 * Wait for ATS to suggest an address and send SYN_ACK */
2335 set_state_and_timeout (n,
2336 GNUNET_TRANSPORT_PS_SYN_RECV_ATS,
2337 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
2339 case GNUNET_TRANSPORT_PS_SYN_RECV_ATS:
2340 /* We already wait for an address to send an SYN_ACK */
2342 case GNUNET_TRANSPORT_PS_SYN_SENT:
2343 case GNUNET_TRANSPORT_PS_SYN_RECV_ACK:
2344 /* Send ACK immediately */
2345 n->ack_state = ACK_SEND_ACK;
2346 send_syn_ack_message (&n->primary_address,
2349 case GNUNET_TRANSPORT_PS_CONNECTED:
2350 /* we are already connected and can thus send the ACK immediately */
2351 GNUNET_assert (NULL != n->primary_address.address);
2352 GNUNET_assert (NULL != n->primary_address.session);
2353 n->ack_state = ACK_SEND_ACK;
2354 send_syn_ack_message (&n->primary_address,
2357 case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
2358 /* We wait for ATS address suggestion */
2360 case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
2361 /* We received a SYN message while waiting for a SYN_ACK in fast
2362 * reconnect. Send SYN_ACK immediately */
2363 n->ack_state = ACK_SEND_ACK;
2364 send_syn_ack_message (&n->primary_address,
2365 n->connect_ack_timestamp);
2367 case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT:
2368 /* We are already connected and can thus send the ACK immediately;
2369 still, it can never hurt to have an alternative address, so also
2370 tell ATS about it */
2371 GNUNET_assert (NULL != n->primary_address.address);
2372 GNUNET_assert (NULL != n->primary_address.session);
2373 n->ack_state = ACK_SEND_ACK;
2374 send_syn_ack_message (&n->primary_address,
2377 case GNUNET_TRANSPORT_PS_DISCONNECT:
2378 /* Get rid of remains and re-try */
2380 n = setup_neighbour (peer);
2381 /* Remember the SYN time stamp for ACK message */
2382 n->ack_state = ACK_SEND_SYN_ACK;
2383 n->connect_ack_timestamp = ts;
2384 /* Request an address for the peer */
2385 set_state_and_timeout (n,
2386 GNUNET_TRANSPORT_PS_SYN_RECV_ATS,
2387 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
2389 case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
2390 /* should not be possible */
2394 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2395 "Unhandled state `%s'\n",
2396 GNUNET_TRANSPORT_ps2s (n->state));
2398 return GNUNET_SYSERR;
2405 * Check if the given @a address is the same that we are already
2406 * using for the respective neighbour. If so, update the bandwidth
2407 * assignment and possibly the session and return #GNUNET_OK.
2408 * If the new address is different from what the neighbour is
2409 * using right now, return #GNUNET_NO.
2411 * @param address address of the other peer,
2412 * @param session session to use or NULL if transport should initiate a session
2413 * @param bandwidth_in inbound quota to be used when connection is up,
2414 * 0 to disconnect from peer
2415 * @param bandwidth_out outbound quota to be used when connection is up,
2416 * 0 to disconnect from peer
2417 * @return #GNUNET_OK if we were able to just update the bandwidth and session,
2418 * #GNUNET_NO if more extensive changes are required (address changed)
2421 try_run_fast_ats_update (const struct GNUNET_HELLO_Address *address,
2422 struct Session *session,
2423 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
2424 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
2426 struct NeighbourMapEntry *n;
2428 n = lookup_neighbour (&address->peer);
2430 (NULL == n->primary_address.address) ||
2431 (0 != GNUNET_HELLO_address_cmp (address,
2432 n->primary_address.address)) )
2434 /* We are not really switching addresses, but merely adjusting
2435 session and/or bandwidth, can do fast ATS update! */
2436 if (session != n->primary_address.session)
2438 /* switch to a different session, but keeping same address; could
2439 happen if there is a 2nd inbound connection */
2440 n->primary_address.session = session;
2442 n->primary_address.bandwidth_in = bandwidth_in;
2443 n->primary_address.bandwidth_out = bandwidth_out;
2444 GST_neighbours_set_incoming_quota (&address->peer,
2446 send_outbound_quota (&address->peer,
2453 * We've been asked to switch addresses, and just now got the result
2454 * from the blacklist check to see if this is allowed.
2456 * @param cls the `struct BlacklistCheckSwitchContext` with
2457 * the information about the future address
2458 * @param peer the peer we may switch addresses on
2459 * @param result #GNUNET_NO if we are not allowed to use the new
2463 switch_address_bl_check_cont (void *cls,
2464 const struct GNUNET_PeerIdentity *peer,
2467 struct BlacklistCheckSwitchContext *blc_ctx = cls;
2468 struct GNUNET_TRANSPORT_PluginFunctions *papi;
2469 struct NeighbourMapEntry *n;
2471 if (result == GNUNET_NO)
2473 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2474 "Blacklist denied to switch to suggested address `%s' session %p for peer `%s'\n",
2475 GST_plugins_a2s (blc_ctx->address),
2477 GNUNET_i2s (&blc_ctx->address->peer));
2478 GNUNET_STATISTICS_update (GST_stats,
2479 "# ATS suggestions ignored (blacklist denied)",
2482 /* FIXME: tell plugin to force killing session here and now
2483 (note: _proper_ plugin API for this does not yet exist) */
2484 GST_ats_block_address (blc_ctx->address,
2489 papi = GST_plugins_find (blc_ctx->address->transport_name);
2490 GNUNET_assert (NULL != papi);
2492 if (NULL == blc_ctx->session)
2494 /* need to create a session, ATS only gave us an address */
2495 blc_ctx->session = papi->get_session (papi->cls,
2497 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2498 "Obtained new session for peer `%s' and address '%s': %p\n",
2499 GNUNET_i2s (&blc_ctx->address->peer),
2500 GST_plugins_a2s (blc_ctx->address),
2502 if (NULL != blc_ctx->session)
2503 GST_ats_new_session (blc_ctx->address,
2506 if (NULL == blc_ctx->session)
2508 /* session creation failed, bad!, fail! */
2509 GNUNET_STATISTICS_update (GST_stats,
2510 "# ATS suggestions ignored (failed to create session)",
2513 /* No session could be obtained, remove blacklist check and clean up */
2514 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2515 "Failed to obtain new session for peer `%s' and address '%s'\n",
2516 GNUNET_i2s (&blc_ctx->address->peer),
2517 GST_plugins_a2s (blc_ctx->address));
2518 GST_ats_block_address (blc_ctx->address,
2523 /* We did this check already before going into blacklist, but
2524 it is theoretically possible that the situation changed in
2525 the meantime, hence we check again here */
2527 try_run_fast_ats_update (blc_ctx->address,
2529 blc_ctx->bandwidth_in,
2530 blc_ctx->bandwidth_out))
2531 goto cleanup; /* was just a minor update, we're done */
2533 /* check if we also need to setup the neighbour entry */
2534 if (NULL == (n = lookup_neighbour (peer)))
2536 n = setup_neighbour (peer);
2537 n->state = GNUNET_TRANSPORT_PS_INIT_ATS;
2540 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2541 "Peer `%s' switches to address `%s'\n",
2542 GNUNET_i2s (&blc_ctx->address->peer),
2543 GST_plugins_a2s (blc_ctx->address));
2547 case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
2549 GST_ats_block_address (blc_ctx->address,
2553 case GNUNET_TRANSPORT_PS_INIT_ATS:
2554 /* We requested an address and ATS suggests one:
2555 * set primary address and send SYN message*/
2556 set_primary_address (n,
2559 blc_ctx->bandwidth_in,
2560 blc_ctx->bandwidth_out);
2561 if (ACK_SEND_SYN_ACK == n->ack_state)
2563 /* Send pending SYN_ACK message */
2564 n->ack_state = ACK_SEND_ACK;
2565 send_syn_ack_message (&n->primary_address,
2566 n->connect_ack_timestamp);
2568 set_state_and_timeout (n,
2569 GNUNET_TRANSPORT_PS_SYN_SENT,
2570 GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT));
2571 send_syn (&n->primary_address);
2573 case GNUNET_TRANSPORT_PS_SYN_SENT:
2574 /* ATS suggested a new address while waiting for an SYN_ACK:
2575 * Switch and send new SYN */
2576 /* ATS suggests a different address, switch again */
2577 set_primary_address (n,
2580 blc_ctx->bandwidth_in,
2581 blc_ctx->bandwidth_out);
2582 if (ACK_SEND_SYN_ACK == n->ack_state)
2584 /* Send pending SYN_ACK message */
2585 n->ack_state = ACK_SEND_ACK;
2586 send_syn_ack_message (&n->primary_address,
2587 n->connect_ack_timestamp);
2589 set_state_and_timeout (n,
2590 GNUNET_TRANSPORT_PS_SYN_SENT,
2591 GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT));
2592 send_syn (&n->primary_address);
2594 case GNUNET_TRANSPORT_PS_SYN_RECV_ATS:
2595 /* We requested an address and ATS suggests one:
2596 * set primary address and send SYN_ACK message*/
2597 set_primary_address (n,
2600 blc_ctx->bandwidth_in,
2601 blc_ctx->bandwidth_out);
2602 /* Send an ACK message as a response to the SYN msg */
2603 set_state_and_timeout (n,
2604 GNUNET_TRANSPORT_PS_SYN_RECV_ACK,
2605 GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT));
2606 send_syn_ack_message (&n->primary_address,
2607 n->connect_ack_timestamp);
2608 if ( (ACK_SEND_SYN_ACK == n->ack_state) ||
2609 (ACK_UNDEFINED == n->ack_state) )
2610 n->ack_state = ACK_SEND_ACK;
2612 case GNUNET_TRANSPORT_PS_SYN_RECV_ACK:
2613 /* ATS asks us to switch while we were trying to connect; switch to new
2614 address and check blacklist again */
2615 if ( (ACK_SEND_SYN_ACK == n->ack_state) )
2617 n->ack_state = ACK_SEND_ACK;
2618 send_syn_ack_message (&n->primary_address,
2619 n->connect_ack_timestamp);
2621 set_primary_address (n,
2624 blc_ctx->bandwidth_in,
2625 blc_ctx->bandwidth_out);
2626 set_state_and_timeout (n,
2627 GNUNET_TRANSPORT_PS_SYN_RECV_ACK,
2628 GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT));
2630 case GNUNET_TRANSPORT_PS_CONNECTED:
2631 GNUNET_assert (NULL != n->primary_address.address);
2632 GNUNET_assert (NULL != n->primary_address.session);
2633 GNUNET_break (n->primary_address.session != blc_ctx->session);
2634 /* ATS asks us to switch a life connection; see if we can get
2635 a SYN_ACK on it before we actually do this! */
2636 set_alternative_address (n,
2639 blc_ctx->bandwidth_in,
2640 blc_ctx->bandwidth_out);
2641 set_state_and_timeout (n,
2642 GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT,
2643 GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT));
2644 GNUNET_STATISTICS_update (GST_stats,
2645 gettext_noop ("# Attempts to switch addresses"),
2648 send_syn (&n->alternative_address);
2650 case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
2651 set_primary_address (n,
2654 blc_ctx->bandwidth_in,
2655 blc_ctx->bandwidth_out);
2656 if (ACK_SEND_SYN_ACK == n->ack_state)
2658 /* Send pending SYN_ACK message */
2659 n->ack_state = ACK_SEND_ACK;
2660 send_syn_ack_message (&n->primary_address,
2661 n->connect_ack_timestamp);
2663 set_state_and_timeout (n,
2664 GNUNET_TRANSPORT_PS_RECONNECT_SENT,
2665 GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT));
2666 send_syn (&n->primary_address);
2668 case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
2669 /* ATS asks us to switch while we were trying to reconnect; switch to new
2670 address and send SYN again */
2671 set_primary_address (n,
2674 blc_ctx->bandwidth_in,
2675 blc_ctx->bandwidth_out);
2676 set_state_and_timeout (n,
2677 GNUNET_TRANSPORT_PS_RECONNECT_SENT,
2678 GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT));
2679 send_syn (&n->primary_address);
2681 case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT:
2682 if ( (0 == GNUNET_HELLO_address_cmp (n->primary_address.address,
2683 blc_ctx->address)) &&
2684 (n->primary_address.session == blc_ctx->session) )
2686 /* ATS switches back to still-active session */
2687 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2688 "ATS double-switched, cleaning up alternative address\n");
2689 free_address (&n->alternative_address);
2690 set_state_and_timeout (n,
2691 GNUNET_TRANSPORT_PS_CONNECTED,
2695 /* ATS asks us to switch a life connection, send */
2696 set_alternative_address (n,
2699 blc_ctx->bandwidth_in,
2700 blc_ctx->bandwidth_out);
2701 set_state_and_timeout (n,
2702 GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT,
2703 GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT));
2704 send_syn (&n->alternative_address);
2706 case GNUNET_TRANSPORT_PS_DISCONNECT:
2707 /* not going to switch addresses while disconnecting */
2708 GNUNET_STATISTICS_update (GST_stats,
2709 "# ATS suggestion ignored (disconnecting)",
2713 case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
2717 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2718 "Unhandled state `%s'\n",
2719 GNUNET_TRANSPORT_ps2s (n->state));
2724 GNUNET_CONTAINER_DLL_remove (pending_bc_head,
2727 GNUNET_HELLO_address_free (blc_ctx->address);
2728 GNUNET_free (blc_ctx);
2733 * For the given peer, switch to this address.
2735 * Before accepting this addresses and actively using it, a blacklist check
2738 * If any check fails or the suggestion can somehow not be followed, we
2739 * MUST call #GST_ats_block_address() to tell ATS that the suggestion
2740 * could not be satisfied and force ATS to do something else.
2742 * @param address address of the other peer,
2743 * @param session session to use or NULL if transport should initiate a session
2744 * @param bandwidth_in inbound quota to be used when connection is up,
2745 * 0 to disconnect from peer
2746 * @param bandwidth_out outbound quota to be used when connection is up,
2747 * 0 to disconnect from peer
2750 GST_neighbours_switch_to_address (const struct GNUNET_HELLO_Address *address,
2751 struct Session *session,
2752 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
2753 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
2755 struct GST_BlacklistCheck *blc;
2756 struct BlacklistCheckSwitchContext *blc_ctx;
2758 GNUNET_assert (NULL != address->transport_name);
2760 try_run_fast_ats_update (address,
2766 /* Check if plugin is available */
2767 if (NULL == (GST_plugins_find (address->transport_name)))
2769 /* we don't have the plugin for this address */
2771 GST_ats_block_address (address,
2775 if ((NULL == session) &&
2776 (GNUNET_HELLO_address_check_option (address,
2777 GNUNET_HELLO_ADDRESS_INFO_INBOUND)))
2779 /* This is a inbound address and we do not have a session to use! */
2781 GST_ats_block_address (address,
2786 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2787 "ATS suggests address '%s' for peer `%s' at %u/%u speed\n",
2788 GST_plugins_a2s (address),
2789 GNUNET_i2s (&address->peer),
2790 (unsigned int) ntohl (bandwidth_in.value__),
2791 (unsigned int) ntohl (bandwidth_out.value__));
2793 /* Perform blacklist check */
2794 blc_ctx = GNUNET_new (struct BlacklistCheckSwitchContext);
2795 blc_ctx->address = GNUNET_HELLO_address_copy (address);
2796 blc_ctx->session = session;
2797 blc_ctx->bandwidth_in = bandwidth_in;
2798 blc_ctx->bandwidth_out = bandwidth_out;
2799 GNUNET_CONTAINER_DLL_insert (pending_bc_head,
2802 if (NULL != (blc = GST_blacklist_test_allowed (&address->peer,
2803 address->transport_name,
2804 &switch_address_bl_check_cont,
2813 * Function called to send network utilization data to ATS for
2814 * each active connection.
2817 * @param key peer we send utilization data for
2818 * @param value the `struct NeighbourMapEntry *` with data to send
2819 * @return #GNUNET_OK (continue to iterate)
2822 send_utilization_data (void *cls,
2823 const struct GNUNET_PeerIdentity *key,
2826 struct NeighbourMapEntry *n = value;
2827 struct GNUNET_ATS_Information atsi[2];
2830 struct GNUNET_TIME_Relative delta;
2832 if ( (GNUNET_YES != test_connected (n)) ||
2833 (NULL == n->primary_address.address) )
2835 delta = GNUNET_TIME_absolute_get_difference (n->last_util_transmission,
2836 GNUNET_TIME_absolute_get ());
2838 if ((0 != n->util_total_bytes_recv) && (0 != delta.rel_value_us))
2839 bps_in = (1000LL * 1000LL * n->util_total_bytes_recv) / (delta.rel_value_us);
2841 if ((0 != n->util_total_bytes_sent) && (0 != delta.rel_value_us))
2842 bps_out = (1000LL * 1000LL * n->util_total_bytes_sent) / delta.rel_value_us;
2844 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2845 "`%s' total: received %u Bytes/s, sent %u Bytes/s\n",
2849 atsi[0].type = htonl (GNUNET_ATS_UTILIZATION_OUT);
2850 atsi[0].value = htonl (bps_out);
2851 atsi[1].type = htonl (GNUNET_ATS_UTILIZATION_IN);
2852 atsi[1].value = htonl (bps_in);
2853 GST_ats_update_metrics (n->primary_address.address,
2854 n->primary_address.session,
2857 n->util_total_bytes_recv = 0;
2858 n->util_total_bytes_sent = 0;
2859 n->last_util_transmission = GNUNET_TIME_absolute_get ();
2865 * Task transmitting utilization in a regular interval
2867 * @param cls the 'struct NeighbourMapEntry' for which we are running
2868 * @param tc scheduler context (unused)
2871 utilization_transmission (void *cls,
2872 const struct GNUNET_SCHEDULER_TaskContext *tc)
2874 util_transmission_tk = NULL;
2875 GNUNET_CONTAINER_multipeermap_iterate (neighbours,
2876 &send_utilization_data,
2878 util_transmission_tk
2879 = GNUNET_SCHEDULER_add_delayed (UTIL_TRANSMISSION_INTERVAL,
2880 &utilization_transmission,
2886 * Track information about data we received from the
2887 * given address (used to notify ATS about our utilization
2888 * of allocated resources).
2890 * @param address the address we got data from
2891 * @param message the message we received (really only the size is used)
2894 GST_neighbours_notify_data_recv (const struct GNUNET_HELLO_Address *address,
2895 const struct GNUNET_MessageHeader *message)
2897 struct NeighbourMapEntry *n;
2899 n = lookup_neighbour (&address->peer);
2902 n->util_total_bytes_recv += ntohs (message->size);
2907 * Track information about data we transmitted using the given @a
2908 * address and @a session (used to notify ATS about our utilization of
2909 * allocated resources).
2911 * @param address the address we transmitted data to
2912 * @param session session we used to transmit data
2913 * @param message the message we sent (really only the size is used)
2916 GST_neighbours_notify_data_sent (const struct GNUNET_HELLO_Address *address,
2917 struct Session *session,
2920 struct NeighbourMapEntry *n;
2922 n = lookup_neighbour (&address->peer);
2925 if (n->primary_address.session != session)
2927 n->util_total_bytes_sent += size;
2932 * Master task run for every neighbour. Performs all of the time-related
2933 * activities (keep alive, send next message, disconnect if idle, finish
2934 * clean up after disconnect).
2936 * @param cls the 'struct NeighbourMapEntry' for which we are running
2937 * @param tc scheduler context (unused)
2940 master_task (void *cls,
2941 const struct GNUNET_SCHEDULER_TaskContext *tc)
2943 struct NeighbourMapEntry *n = cls;
2944 struct GNUNET_TIME_Relative delay;
2947 delay = GNUNET_TIME_absolute_get_remaining (n->timeout);
2948 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2949 "Master task runs for neighbour `%s' in state %s with timeout in %s\n",
2950 GNUNET_i2s (&n->id),
2951 GNUNET_TRANSPORT_ps2s(n->state),
2952 GNUNET_STRINGS_relative_time_to_string (delay,
2956 case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
2957 /* invalid state for master task, clean up */
2961 case GNUNET_TRANSPORT_PS_INIT_ATS:
2962 if (0 == delay.rel_value_us)
2964 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2965 "Connection to `%s' timed out waiting for ATS to provide address\n",
2966 GNUNET_i2s (&n->id));
2971 case GNUNET_TRANSPORT_PS_SYN_SENT:
2972 if (0 == delay.rel_value_us)
2974 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2975 "Connection to `%s' timed out waiting for other peer to send SYN_ACK\n",
2976 GNUNET_i2s (&n->id));
2977 /* Remove address and request and additional one */
2978 unset_primary_address (n);
2979 set_state_and_timeout (n,
2980 GNUNET_TRANSPORT_PS_INIT_ATS,
2981 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
2985 case GNUNET_TRANSPORT_PS_SYN_RECV_ATS:
2986 if (0 == delay.rel_value_us)
2988 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2989 "Connection to `%s' timed out waiting ATS to provide address to use for SYN_ACK\n",
2990 GNUNET_i2s (&n->id));
2995 case GNUNET_TRANSPORT_PS_SYN_RECV_ACK:
2996 if (0 == delay.rel_value_us)
2998 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2999 "Connection to `%s' timed out waiting for other peer to send ACK\n",
3000 GNUNET_i2s (&n->id));
3001 disconnect_neighbour (n);
3005 case GNUNET_TRANSPORT_PS_CONNECTED:
3006 if (0 == delay.rel_value_us)
3008 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3009 "Connection to `%s' timed out, missing KEEPALIVE_RESPONSEs\n",
3010 GNUNET_i2s (&n->id));
3011 disconnect_neighbour (n);
3014 try_transmission_to_peer (n);
3017 case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
3018 if (0 == delay.rel_value_us)
3020 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3021 "Connection to `%s' timed out, waiting for ATS replacement address\n",
3022 GNUNET_i2s (&n->id));
3023 disconnect_neighbour (n);
3027 case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
3028 if (0 == delay.rel_value_us)
3030 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3031 "Connection to `%s' timed out, waiting for other peer to SYN_ACK replacement address\n",
3032 GNUNET_i2s (&n->id));
3033 disconnect_neighbour (n);
3037 case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT:
3038 if (0 == delay.rel_value_us)
3040 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3041 "Switch failed, cleaning up alternative address\n");
3042 free_address (&n->alternative_address);
3043 set_state_and_timeout (n,
3044 GNUNET_TRANSPORT_PS_CONNECTED,
3045 GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT));
3047 try_transmission_to_peer (n);
3050 case GNUNET_TRANSPORT_PS_DISCONNECT:
3051 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3052 "Cleaning up connection to `%s' after sending DISCONNECT\n",
3053 GNUNET_i2s (&n->id));
3056 case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
3057 /* how did we get here!? */
3061 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3062 "Unhandled state `%s'\n",
3063 GNUNET_TRANSPORT_ps2s (n->state));
3067 delay = GNUNET_TIME_absolute_get_remaining (n->timeout);
3068 if ( (GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT == n->state) ||
3069 (GNUNET_TRANSPORT_PS_CONNECTED == n->state) )
3071 /* if we are *now* in one of the two states, we're sending
3072 keep alive messages, so we need to consider the keepalive
3073 delay, not just the connection timeout */
3074 delay = GNUNET_TIME_relative_min (GNUNET_TIME_absolute_get_remaining (n->keep_alive_time),
3077 if (NULL == n->task)
3078 n->task = GNUNET_SCHEDULER_add_delayed (delay,
3085 * Send a ACK message to the neighbour to confirm that we
3088 * @param n neighbour to send the ACK to
3091 send_session_ack_message (struct NeighbourMapEntry *n)
3093 struct GNUNET_MessageHeader msg;
3095 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3096 "Sending ACK message to peer `%s'\n",
3097 GNUNET_i2s (&n->id));
3099 msg.size = htons (sizeof (struct GNUNET_MessageHeader));
3100 msg.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_ACK);
3101 (void) send_with_session (n,
3103 sizeof (struct GNUNET_MessageHeader),
3105 GNUNET_TIME_UNIT_FOREVER_REL,
3112 * We received a 'SESSION_SYN_ACK' message from the other peer.
3113 * Consider switching to it.
3115 * @param message possibly a `struct SessionConnectMessage` (check format)
3116 * @param peer identity of the peer to switch the address for
3117 * @param address address of the other peer, NULL if other peer
3119 * @param session session to use (or NULL)
3120 * @return #GNUNET_OK if the message was fine, #GNUNET_SYSERR on serious error
3123 GST_neighbours_handle_session_syn_ack (const struct GNUNET_MessageHeader *message,
3124 const struct GNUNET_HELLO_Address *address,
3125 struct Session *session)
3127 const struct TransportSynMessage *scm;
3128 struct GNUNET_TIME_Absolute ts;
3129 struct NeighbourMapEntry *n;
3131 if (ntohs (message->size) != sizeof (struct TransportSynMessage))
3133 GNUNET_break_op (0);
3134 return GNUNET_SYSERR;
3136 GNUNET_STATISTICS_update (GST_stats,
3138 ("# SYN_ACK messages received"),
3140 scm = (const struct TransportSynMessage *) message;
3141 GNUNET_break_op (ntohl (scm->reserved) == 0);
3142 if (NULL == (n = lookup_neighbour (&address->peer)))
3144 GNUNET_STATISTICS_update (GST_stats,
3146 ("# unexpected SYN_ACK messages (no peer)"),
3148 return GNUNET_SYSERR;
3150 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3151 "Received SYN_ACK message from peer `%s' in state %s/%s\n",
3152 GNUNET_i2s (&address->peer),
3153 GNUNET_TRANSPORT_ps2s (n->state),
3154 print_ack_state (n->ack_state));
3155 ts = GNUNET_TIME_absolute_ntoh (scm->timestamp);
3158 case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
3161 return GNUNET_SYSERR;
3162 case GNUNET_TRANSPORT_PS_INIT_ATS:
3163 GNUNET_STATISTICS_update (GST_stats,
3164 gettext_noop ("# unexpected SYN_ACK messages (not ready)"),
3168 case GNUNET_TRANSPORT_PS_SYN_SENT:
3169 if (ts.abs_value_us != n->primary_address.connect_timestamp.abs_value_us)
3171 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3172 "SYN_ACK ignored as the timestamp does not match our SYN request\n");
3175 set_state_and_timeout (n,
3176 GNUNET_TRANSPORT_PS_CONNECTED,
3177 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT));
3178 set_primary_address (n,
3179 n->primary_address.address,
3180 n->primary_address.session,
3181 n->primary_address.bandwidth_in,
3182 n->primary_address.bandwidth_out);
3183 send_session_ack_message (n);
3185 case GNUNET_TRANSPORT_PS_SYN_RECV_ATS:
3186 case GNUNET_TRANSPORT_PS_SYN_RECV_ACK:
3187 GNUNET_STATISTICS_update (GST_stats,
3188 gettext_noop ("# unexpected SYN_ACK messages (not ready)"),
3192 case GNUNET_TRANSPORT_PS_CONNECTED:
3193 /* duplicate SYN_ACK, let's answer by duplicate ACK just in case */
3194 send_session_ack_message (n);
3196 case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
3197 /* we didn't expect any SYN_ACK, as we are waiting for ATS
3198 to give us a new address... */
3199 GNUNET_STATISTICS_update (GST_stats,
3200 gettext_noop ("# unexpected SYN_ACK messages (waiting on ATS)"),
3204 case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
3205 /* Reconnecting with new address address worked; go back to connected! */
3206 set_state_and_timeout (n,
3207 GNUNET_TRANSPORT_PS_CONNECTED,
3208 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT));
3209 send_session_ack_message (n);
3211 case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT:
3212 /* new address worked; adopt it and go back to connected! */
3213 set_state_and_timeout (n,
3214 GNUNET_TRANSPORT_PS_CONNECTED,
3215 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT));
3216 GNUNET_break (GNUNET_NO == n->alternative_address.ats_active);
3218 /* Set primary addresses */
3219 set_primary_address (n,
3220 n->alternative_address.address,
3221 n->alternative_address.session,
3222 n->alternative_address.bandwidth_in,
3223 n->alternative_address.bandwidth_out);
3224 GNUNET_STATISTICS_update (GST_stats,
3225 gettext_noop ("# Successful attempts to switch addresses"),
3229 GNUNET_HELLO_address_free (n->alternative_address.address);
3230 memset (&n->alternative_address,
3232 sizeof (n->alternative_address));
3233 send_session_ack_message (n);
3235 case GNUNET_TRANSPORT_PS_DISCONNECT:
3236 GNUNET_STATISTICS_update (GST_stats,
3238 ("# unexpected SYN_ACK messages (disconnecting)"),
3240 return GNUNET_SYSERR;
3241 case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
3245 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3246 "Unhandled state `%s'\n",
3247 GNUNET_TRANSPORT_ps2s (n->state));
3249 return GNUNET_SYSERR;
3256 * A session was terminated. Take note; if needed, try to get
3257 * an alternative address from ATS.
3259 * @param peer identity of the peer where the session died
3260 * @param session session that is gone
3261 * @return #GNUNET_YES if this was a session used, #GNUNET_NO if
3262 * this session was not in use
3265 GST_neighbours_session_terminated (const struct GNUNET_PeerIdentity *peer,
3266 struct Session *session)
3268 struct NeighbourMapEntry *n;
3269 struct BlackListCheckContext *bcc;
3270 struct BlackListCheckContext *bcc_next;
3272 /* make sure to cancel all ongoing blacklist checks involving 'session' */
3274 while (NULL != (bcc = bcc_next))
3276 bcc_next = bcc->next;
3277 if (bcc->na.session == session)
3279 if (NULL != bcc->bc)
3280 GST_blacklist_test_cancel (bcc->bc);
3281 GNUNET_HELLO_address_free (bcc->na.address);
3282 GNUNET_CONTAINER_DLL_remove (bc_head,
3288 if (NULL == (n = lookup_neighbour (peer)))
3289 return GNUNET_NO; /* can't affect us */
3290 if (session != n->primary_address.session)
3292 /* Free alternative address */
3293 if (session == n->alternative_address.session)
3295 if (GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT == n->state)
3296 set_state_and_timeout (n,
3297 GNUNET_TRANSPORT_PS_CONNECTED,
3299 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3300 "Session died, cleaning up alternative address\n");
3301 free_address (&n->alternative_address);
3303 return GNUNET_NO; /* doesn't affect us further */
3306 n->expect_latency_response = GNUNET_NO;
3307 /* The session for neighbour's primary address died */
3310 case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
3314 case GNUNET_TRANSPORT_PS_INIT_ATS:
3318 case GNUNET_TRANSPORT_PS_SYN_SENT:
3319 /* The session used to send the SYN terminated:
3320 * this implies a connect error*/
3321 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3322 "Failed to send SYN in %s with `%s' %p: session terminated\n",
3324 GST_plugins_a2s (n->primary_address.address),
3325 n->primary_address.session,
3328 /* Destroy the address since it cannot be used */
3329 unset_primary_address (n);
3330 set_state_and_timeout (n,
3331 GNUNET_TRANSPORT_PS_INIT_ATS,
3332 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
3334 case GNUNET_TRANSPORT_PS_SYN_RECV_ATS:
3335 case GNUNET_TRANSPORT_PS_SYN_RECV_ACK:
3336 /* error on inbound session; free neighbour entirely */
3339 case GNUNET_TRANSPORT_PS_CONNECTED:
3340 /* Our primary connection died, try a fast reconnect */
3341 unset_primary_address (n);
3342 set_state_and_timeout (n,
3343 GNUNET_TRANSPORT_PS_RECONNECT_ATS,
3344 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
3346 case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
3347 /* we don't have an address, how can it go down? */
3350 case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
3351 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3352 "Failed to send SYN in %s with `%s' %p: session terminated\n",
3354 GST_plugins_a2s (n->primary_address.address),
3355 n->primary_address.session,
3357 /* Destroy the address since it cannot be used */
3358 unset_primary_address (n);
3359 set_state_and_timeout (n,
3360 GNUNET_TRANSPORT_PS_RECONNECT_ATS,
3361 GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
3363 case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT:
3364 /* primary went down while we were waiting for SYN_ACK on secondary;
3365 secondary as primary */
3367 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3368 "Connection `%s' %p to peer `%s' was terminated while switching, "
3369 "switching to alternative address `%s' %p\n",
3370 GST_plugins_a2s (n->primary_address.address),
3371 n->primary_address.session,
3373 GST_plugins_a2s (n->alternative_address.address),
3374 n->alternative_address.session);
3376 /* Destroy the inbound address since it cannot be used */
3377 free_address (&n->primary_address);
3378 n->primary_address = n->alternative_address;
3379 memset (&n->alternative_address,
3381 sizeof (struct NeighbourAddress));
3382 set_state_and_timeout (n,
3383 GNUNET_TRANSPORT_PS_RECONNECT_SENT,
3384 GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT));
3386 case GNUNET_TRANSPORT_PS_DISCONNECT:
3387 unset_primary_address (n);
3389 case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
3390 /* neighbour was freed and plugins told to terminate session */
3393 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3394 "Unhandled state `%s'\n",
3395 GNUNET_TRANSPORT_ps2s (n->state));
3399 if (NULL != n->task)
3400 GNUNET_SCHEDULER_cancel (n->task);
3401 n->task = GNUNET_SCHEDULER_add_now (&master_task, n);
3407 * We received a 'ACK' message from the other peer.
3408 * If we sent a 'SYN_ACK' last, this means we are now
3409 * connected. Otherwise, do nothing.
3411 * @param message possibly a 'struct SessionConnectMessage' (check format)
3412 * @param address address of the other peer
3413 * @param session session to use (or NULL)
3414 * @return #GNUNET_OK if the message was fine, #GNUNET_SYSERR on serious error
3417 GST_neighbours_handle_session_ack (const struct GNUNET_MessageHeader *message,
3418 const struct GNUNET_HELLO_Address *address,
3419 struct Session *session)
3421 struct NeighbourMapEntry *n;
3423 if (ntohs (message->size) != sizeof (struct GNUNET_MessageHeader))
3425 GNUNET_break_op (0);
3426 return GNUNET_SYSERR;
3428 GNUNET_STATISTICS_update (GST_stats,
3430 ("# ACK messages received"),
3432 if (NULL == (n = lookup_neighbour (&address->peer)))
3434 GNUNET_break_op (0);
3435 return GNUNET_SYSERR;
3437 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3438 "Received ACK for peer `%s' in state %s/%s\n",
3439 GNUNET_i2s (&address->peer),
3440 GNUNET_TRANSPORT_ps2s (n->state),
3441 print_ack_state (n->ack_state));
3443 /* Check if we are in a plausible state for having sent
3444 a SYN_ACK. If not, return, otherwise break.
3446 The remote peers sends a ACK as a response for a SYN_ACK
3450 - If a remote peer has sent a SYN, we responded with a SYN_ACK and
3451 now wait for the ACK to finally be connected
3452 - If we sent a SYN_ACK to this peer before */
3454 if ( (GNUNET_TRANSPORT_PS_SYN_RECV_ACK != n->state) &&
3455 (ACK_SEND_ACK != n->ack_state))
3457 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3458 "Received unexpected ACK message from peer `%s' in state %s/%s\n",
3459 GNUNET_i2s (&address->peer),
3460 GNUNET_TRANSPORT_ps2s (n->state),
3461 print_ack_state (n->ack_state));
3463 GNUNET_STATISTICS_update (GST_stats,
3464 gettext_noop ("# unexpected ACK messages"), 1,
3468 if (GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT == n->state)
3470 /* We tried to switch addresses while being connect. We explicitly wait
3471 * for a SYN_ACK before going to GNUNET_TRANSPORT_PS_CONNECTED,
3472 * so we do not want to set the address as in use! */
3475 set_state_and_timeout (n,
3476 GNUNET_TRANSPORT_PS_CONNECTED,
3477 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT));
3479 /* Set primary address to used */
3480 set_primary_address (n,
3481 n->primary_address.address,
3482 n->primary_address.session,
3483 n->primary_address.bandwidth_in,
3484 n->primary_address.bandwidth_out);
3490 * Test if we're connected to the given peer.
3492 * @param target peer to test
3493 * @return #GNUNET_YES if we are connected, #GNUNET_NO if not
3496 GST_neighbours_test_connected (const struct GNUNET_PeerIdentity *target)
3498 return test_connected (lookup_neighbour (target));
3503 * Change the incoming quota for the given peer.
3505 * @param neighbour identity of peer to change qutoa for
3506 * @param quota new quota
3509 GST_neighbours_set_incoming_quota (const struct GNUNET_PeerIdentity *neighbour,
3510 struct GNUNET_BANDWIDTH_Value32NBO quota)
3512 struct NeighbourMapEntry *n;
3514 if (NULL == (n = lookup_neighbour (neighbour)))
3516 GNUNET_STATISTICS_update (GST_stats,
3518 ("# SET QUOTA messages ignored (no such peer)"),
3522 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3523 "Setting inbound quota of %u Bps for peer `%s' to all clients\n",
3524 ntohl (quota.value__), GNUNET_i2s (&n->id));
3525 GNUNET_BANDWIDTH_tracker_update_quota (&n->in_tracker, quota);
3526 if (0 != ntohl (quota.value__))
3528 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3529 "Disconnecting peer `%4s' due to SET_QUOTA\n",
3530 GNUNET_i2s (&n->id));
3531 if (GNUNET_YES == test_connected (n))
3532 GNUNET_STATISTICS_update (GST_stats,
3533 gettext_noop ("# disconnects due to quota of 0"),
3535 disconnect_neighbour (n);
3540 * Task to asynchronously run #free_neighbour().
3542 * @param cls the `struct NeighbourMapEntry` to free
3546 delayed_disconnect (void *cls,
3547 const struct GNUNET_SCHEDULER_TaskContext* tc)
3549 struct NeighbourMapEntry *n = cls;
3551 n->delayed_disconnect_task = NULL;
3552 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3553 "Disconnecting by request from peer %s\n",
3554 GNUNET_i2s (&n->id));
3560 * We received a disconnect message from the given peer,
3561 * validate and process.
3563 * @param peer sender of the message
3564 * @param msg the disconnect message
3567 GST_neighbours_handle_disconnect_message (const struct GNUNET_PeerIdentity *peer,
3568 const struct GNUNET_MessageHeader *msg)
3570 struct NeighbourMapEntry *n;
3571 const struct SessionDisconnectMessage *sdm;
3573 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3574 "Received DISCONNECT message from peer `%s'\n",
3576 if (ntohs (msg->size) != sizeof (struct SessionDisconnectMessage))
3578 GNUNET_break_op (0);
3579 GNUNET_STATISTICS_update (GST_stats,
3581 ("# disconnect messages ignored (malformed)"), 1,
3585 GNUNET_STATISTICS_update (GST_stats,
3587 ("# DISCONNECT messages received"),
3589 sdm = (const struct SessionDisconnectMessage *) msg;
3590 if (NULL == (n = lookup_neighbour (peer)))
3595 if (GNUNET_TIME_absolute_ntoh (sdm->timestamp).abs_value_us <= n->connect_ack_timestamp.abs_value_us)
3597 GNUNET_STATISTICS_update (GST_stats,
3598 gettext_noop ("# disconnect messages ignored (timestamp)"),
3603 if (0 != memcmp (peer,
3605 sizeof (struct GNUNET_PeerIdentity)))
3607 GNUNET_break_op (0);
3610 if (ntohl (sdm->purpose.size) !=
3611 sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
3612 sizeof (struct GNUNET_CRYPTO_EddsaPublicKey) +
3613 sizeof (struct GNUNET_TIME_AbsoluteNBO))
3615 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3616 "DISCONNECT message from peer `%s' has invalid size\n",
3618 GNUNET_break_op (0);
3622 GNUNET_CRYPTO_eddsa_verify (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT,
3627 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3628 "DISCONNECT message from peer `%s' cannot be verified \n",
3630 GNUNET_break_op (0);
3633 n->delayed_disconnect_task = GNUNET_SCHEDULER_add_now (&delayed_disconnect, n);
3638 * Closure for the #neighbours_iterate() function.
3640 struct IteratorContext
3643 * Function to call on each connected neighbour.
3645 GST_NeighbourIterator cb;
3648 * Closure for @e cb.
3655 * Call the callback from the closure for each neighbour.
3657 * @param cls the `struct IteratorContext`
3658 * @param key the hash of the public key of the neighbour
3659 * @param value the `struct NeighbourMapEntry`
3660 * @return #GNUNET_OK (continue to iterate)
3663 neighbours_iterate (void *cls,
3664 const struct GNUNET_PeerIdentity *key,
3667 struct IteratorContext *ic = cls;
3668 struct NeighbourMapEntry *n = value;
3669 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in;
3670 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out;
3672 if (NULL != n->primary_address.address)
3674 bandwidth_in = n->primary_address.bandwidth_in;
3675 bandwidth_out = n->primary_address.bandwidth_out;
3679 bandwidth_in = GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT;
3680 bandwidth_out = GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT;
3684 n->primary_address.address,
3687 bandwidth_in, bandwidth_out);
3693 * Iterate over all connected neighbours.
3695 * @param cb function to call
3696 * @param cb_cls closure for cb
3699 GST_neighbours_iterate (GST_NeighbourIterator cb, void *cb_cls)
3701 struct IteratorContext ic;
3703 if (NULL == neighbours)
3704 return; /* can happen during shutdown */
3707 GNUNET_CONTAINER_multipeermap_iterate (neighbours,
3708 &neighbours_iterate,
3714 * If we have an active connection to the given target, it must be shutdown.
3716 * @param target peer to disconnect from
3719 GST_neighbours_force_disconnect (const struct GNUNET_PeerIdentity *target)
3721 struct NeighbourMapEntry *n;
3723 if (NULL == (n = lookup_neighbour (target)))
3724 return; /* not active */
3725 if (GNUNET_YES == test_connected (n))
3726 GNUNET_STATISTICS_update (GST_stats,
3727 gettext_noop ("# disconnected from peer upon explicit request"),
3730 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3731 "Forced disconnect from peer %s\n",
3732 GNUNET_i2s (target));
3733 disconnect_neighbour (n);
3738 * Obtain current address information for the given neighbour.
3741 * @return address currently used
3743 struct GNUNET_HELLO_Address *
3744 GST_neighbour_get_current_address (const struct GNUNET_PeerIdentity *peer)
3746 struct NeighbourMapEntry *n;
3748 n = lookup_neighbour (peer);
3751 return n->primary_address.address;
3756 * Initialize the neighbours subsystem.
3758 * @param max_fds maximum number of fds to use
3761 GST_neighbours_start (unsigned int max_fds)
3763 neighbours = GNUNET_CONTAINER_multipeermap_create (NEIGHBOUR_TABLE_SIZE,
3765 util_transmission_tk = GNUNET_SCHEDULER_add_delayed (UTIL_TRANSMISSION_INTERVAL,
3766 &utilization_transmission,
3772 * Disconnect from the given neighbour.
3775 * @param key hash of neighbour's public key (not used)
3776 * @param value the 'struct NeighbourMapEntry' of the neighbour
3777 * @return #GNUNET_OK (continue to iterate)
3780 disconnect_all_neighbours (void *cls,
3781 const struct GNUNET_PeerIdentity *key,
3784 struct NeighbourMapEntry *n = value;
3786 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3787 "Disconnecting peer `%4s' during shutdown\n",
3788 GNUNET_i2s (&n->id));
3795 * Cleanup the neighbours subsystem.
3798 GST_neighbours_stop ()
3800 struct BlacklistCheckSwitchContext *cur;
3801 struct BlacklistCheckSwitchContext *next;
3803 if (NULL == neighbours)
3805 if (NULL != util_transmission_tk)
3807 GNUNET_SCHEDULER_cancel (util_transmission_tk);
3808 util_transmission_tk = NULL;
3810 GNUNET_CONTAINER_multipeermap_iterate (neighbours,
3811 &disconnect_all_neighbours,
3813 GNUNET_CONTAINER_multipeermap_destroy (neighbours);
3815 next = pending_bc_head;
3816 for (cur = next; NULL != cur; cur = next)
3819 GNUNET_CONTAINER_DLL_remove (pending_bc_head,
3823 if (NULL != cur->blc)
3825 GST_blacklist_test_cancel (cur->blc);
3828 if (NULL != cur->address)
3829 GNUNET_HELLO_address_free (cur->address);
3835 /* end of file gnunet-service-transport_neighbours.c */