2 This file is part of GNUnet
3 (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
8 option) any later version.
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file transport/plugin_transport_tcp.c
23 * @brief Implementation of the TCP transport service
24 * @author Christian Grothoff
28 #include "gnunet_hello_lib.h"
29 #include "gnunet_connection_lib.h"
30 #include "gnunet_os_lib.h"
31 #include "gnunet_peerinfo_service.h"
32 #include "gnunet_protocols.h"
33 #include "gnunet_resolver_service.h"
34 #include "gnunet_server_lib.h"
35 #include "gnunet_service_lib.h"
36 #include "gnunet_signatures.h"
37 #include "gnunet_statistics_service.h"
38 #include "gnunet_transport_service.h"
39 #include "plugin_transport.h"
40 #include "transport.h"
42 #define DEBUG_TCP GNUNET_NO
45 * After how long do we expire an address that we
46 * learned from another peer if it is not reconfirmed
49 #define LEARNED_ADDRESS_EXPIRATION GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 6)
52 * How long until we give up on transmitting the welcome message?
54 #define WELCOME_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)
57 * How long until we give up on transmitting the welcome message?
59 #define HOSTNAME_RESOLVE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
62 * For how many messages back to we keep transmission times?
64 #define ACK_LOG_SIZE 32
69 * Message used to ask a peer to validate receipt (to check an address
70 * from a HELLO). Followed by the address used. Note that the
71 * recipients response does not affirm that he has this address,
72 * only that he got the challenge message.
74 struct ValidationChallengeMessage
78 * Type will be GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_PING
80 struct GNUNET_MessageHeader header;
83 * Random challenge number (in network byte order).
85 uint32_t challenge GNUNET_PACKED;
88 * Who is the intended recipient?
90 struct GNUNET_PeerIdentity target;
96 * Message used to validate a HELLO. The challenge is included in the
97 * confirmation to make matching of replies to requests possible. The
98 * signature signs the original challenge number, our public key, the
99 * sender's address (so that the sender can check that the address we
100 * saw is plausible for him and possibly detect a MiM attack) and a
101 * timestamp (to limit replay).<p>
103 * This message is followed by the address of the
104 * client that we are observing (which is part of what
107 struct ValidationChallengeResponse
111 * Type will be GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_PONG
113 struct GNUNET_MessageHeader header;
116 * For padding, always zero.
118 uint32_t reserved GNUNET_PACKED;
123 struct GNUNET_CRYPTO_RsaSignature signature;
126 * What are we signing and why?
128 struct GNUNET_CRYPTO_RsaSignaturePurpose purpose;
131 * Random challenge number (in network byte order).
133 uint32_t challenge GNUNET_PACKED;
136 * Who signed this message?
138 struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded signer;
145 * Initial handshake message for a session. This header
146 * is followed by the address that the other peer used to
147 * connect to us (so that we may learn it) or the address
148 * that the other peer got from the accept call.
150 struct WelcomeMessage
152 struct GNUNET_MessageHeader header;
155 * Identity of the node connecting (TCP client)
157 struct GNUNET_PeerIdentity clientIdentity;
163 * Encapsulation for normal TCP traffic.
167 struct GNUNET_MessageHeader header;
172 uint32_t reserved GNUNET_PACKED;
175 * Number of the last message that was received from the other peer.
177 uint64_t ack_in GNUNET_PACKED;
180 * Number of this outgoing message.
182 uint64_t ack_out GNUNET_PACKED;
185 * How long was sending this ack delayed by the other peer
186 * (estimate). The receiver of this message can use the delay
187 * between sending his message number 'ack' and receiving this ack
188 * minus the delay as an estimate of the round-trip time.
190 struct GNUNET_TIME_RelativeNBO delay;
196 * Encapsulation of all of the state of the plugin.
202 * Information kept for each message that is yet to
205 struct PendingMessage
209 * This is a linked list.
211 struct PendingMessage *next;
214 * The pending message, pointer to the end
215 * of this struct, do not free!
217 struct GNUNET_MessageHeader *msg;
220 * Continuation function to call once the message
221 * has been sent. Can be NULL if there is no
222 * continuation to call.
224 GNUNET_TRANSPORT_TransmitContinuation transmit_cont;
227 * Closure for transmit_cont.
229 void *transmit_cont_cls;
232 * Timeout value for the pending message.
234 struct GNUNET_TIME_Absolute timeout;
237 * GNUNET_YES if this is a welcome message;
238 * otherwise this should be a DATA message.
246 * Session handle for TCP connections.
252 * Stored in a linked list.
254 struct Session *next;
257 * Pointer to the global plugin struct.
259 struct Plugin *plugin;
262 * The client (used to identify this connection)
264 struct GNUNET_SERVER_Client *client;
267 * Messages currently pending for transmission
268 * to this peer, if any.
270 struct PendingMessage *pending_messages;
273 * Handle for pending transmission request.
275 struct GNUNET_CONNECTION_TransmitHandle *transmit_handle;
278 * To whom are we talking to (set to our identity
279 * if we are still waiting for the welcome message)
281 struct GNUNET_PeerIdentity target;
284 * At what time did we reset last_received last?
286 struct GNUNET_TIME_Absolute last_quota_update;
289 * Context for our iteration to find HELLOs for this peer. NULL
290 * after iteration has completed.
292 struct GNUNET_PEERINFO_IteratorContext *ic;
295 * Address of the other peer if WE initiated the connection
296 * (and hence can be sure what it is), otherwise NULL.
301 * How many bytes have we received since the "last_quota_update"
304 uint64_t last_received;
307 * Our current latency estimate (in ms).
309 double latency_estimate;
312 * Time when we generated the last ACK_LOG_SIZE acks.
313 * (the "last" refers to the "out_msg_counter" here)
315 struct GNUNET_TIME_Absolute gen_time[ACK_LOG_SIZE];
318 * Our current sequence number.
320 uint64_t out_msg_counter;
323 * Highest received incoming sequence number.
325 uint64_t max_in_msg_counter;
328 * Number of bytes per ms that this peer is allowed
334 * Length of connect_addr, can be 0.
339 * Are we still expecting the welcome message? (GNUNET_YES/GNUNET_NO)
340 * GNUNET_SYSERR is used to mark non-welcoming connections (HELLO
343 int expecting_welcome;
349 * Encapsulation of all of the state of the plugin.
356 struct GNUNET_TRANSPORT_PluginEnvironment *env;
361 struct GNUNET_CONNECTION_Handle *lsock;
364 * List of open TCP sessions.
366 struct Session *sessions;
369 * Handle for the statistics service.
371 struct GNUNET_STATISTICS_Handle *statistics;
374 * Handle to the network service.
376 struct GNUNET_SERVICE_Context *service;
379 * Handle to the server for this service.
381 struct GNUNET_SERVER_Handle *server;
384 * Copy of the handler array where the closures are
385 * set to this struct's instance.
387 struct GNUNET_SERVER_MessageHandler *handlers;
390 * Handle for request of hostname resolution, non-NULL if pending.
392 struct GNUNET_RESOLVER_RequestHandle *hostname_dns;
395 * ID of task used to update our addresses when one expires.
397 GNUNET_SCHEDULER_TaskIdentifier address_update_task;
400 * Port that we are actually listening on.
405 * Port that the user said we would have visible to the
414 * Find the session handle for the given peer.
416 static struct Session *
417 find_session_by_target (struct Plugin *plugin,
418 const struct GNUNET_PeerIdentity *target)
422 ret = plugin->sessions;
423 while ((ret != NULL) &&
424 ((GNUNET_SYSERR == ret->expecting_welcome) ||
425 (0 != memcmp (target,
426 &ret->target, sizeof (struct GNUNET_PeerIdentity)))))
433 * Find the session handle for the given peer.
435 static struct Session *
436 find_session_by_client (struct Plugin *plugin,
437 const struct GNUNET_SERVER_Client *client)
441 ret = plugin->sessions;
442 while ((ret != NULL) && (client != ret->client))
449 * Create a welcome message.
451 static struct PendingMessage *
452 create_welcome (size_t addrlen, const void *addr, struct Plugin *plugin)
454 struct PendingMessage *pm;
455 struct WelcomeMessage *welcome;
457 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
458 sizeof (struct WelcomeMessage) + addrlen);
459 pm->msg = (struct GNUNET_MessageHeader *) &pm[1];
460 welcome = (struct WelcomeMessage *) &pm[1];
461 welcome->header.size = htons (sizeof (struct WelcomeMessage) + addrlen);
462 welcome->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME);
463 GNUNET_CRYPTO_hash (plugin->env->my_public_key,
464 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
465 &welcome->clientIdentity.hashPubKey);
466 memcpy (&welcome[1], addr, addrlen);
467 pm->timeout = GNUNET_TIME_relative_to_absolute (WELCOME_TIMEOUT);
468 pm->is_welcome = GNUNET_YES;
474 * Create a new session using the specified address
475 * for the welcome message.
478 * @param target peer to connect to
479 * @param client client to use
480 * @param addrlen IPv4 or IPv6
481 * @param addr either struct sockaddr_in or struct sockaddr_in6
482 * @return NULL connection failed / invalid address
484 static struct Session *
485 create_session (struct Plugin *plugin,
486 const struct GNUNET_PeerIdentity *target,
487 struct GNUNET_SERVER_Client *client,
488 const void *addr, size_t addrlen)
492 ret = GNUNET_malloc (sizeof (struct Session));
493 ret->plugin = plugin;
494 ret->next = plugin->sessions;
495 plugin->sessions = ret;
496 ret->client = client;
497 ret->target = *target;
498 ret->last_quota_update = GNUNET_TIME_absolute_get ();
499 ret->quota_in = plugin->env->default_quota_in;
500 ret->expecting_welcome = GNUNET_YES;
501 ret->pending_messages = create_welcome (addrlen, addr, plugin);
507 * If we have pending messages, ask the server to
508 * transmit them (schedule the respective tasks, etc.)
510 * @param session for which session should we do this
512 static void process_pending_messages (struct Session *session);
516 * Function called to notify a client about the socket
517 * being ready to queue more data. "buf" will be
518 * NULL and "size" zero if the socket was closed for
519 * writing in the meantime.
522 * @param size number of bytes available in buf
523 * @param buf where the callee should write the message
524 * @return number of bytes written to buf
527 do_transmit (void *cls, size_t size, void *buf)
529 struct Session *session = cls;
530 struct PendingMessage *pm;
534 struct DataMessage *dm;
536 session->transmit_handle = NULL;
540 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
542 "Timeout trying to transmit to peer `%4s', discarding message queue.\n",
543 GNUNET_i2s (&session->target));
546 while (NULL != (pm = session->pending_messages))
548 session->pending_messages = pm->next;
550 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
552 "Failed to transmit message of type %u to `%4s'.\n",
553 ntohs (pm->msg->type),
554 GNUNET_i2s (&session->target));
556 if (pm->transmit_cont != NULL)
557 pm->transmit_cont (pm->transmit_cont_cls,
558 &session->target, GNUNET_SYSERR);
565 while (NULL != (pm = session->pending_messages))
569 if (size < (msize = ntohs (pm->msg->size)))
571 memcpy (cbuf, pm->msg, msize);
579 sizeof (struct DataMessage) + (msize = ntohs (pm->msg->size)))
581 dm = (struct DataMessage *) cbuf;
582 dm->header.size = htons (sizeof (struct DataMessage) + msize);
583 dm->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_DATA);
584 dm->ack_out = GNUNET_htonll (++session->out_msg_counter);
585 dm->ack_in = GNUNET_htonll (session->max_in_msg_counter);
586 cbuf += sizeof (struct DataMessage);
587 ret += sizeof (struct DataMessage);
588 size -= sizeof (struct DataMessage);
589 memcpy (cbuf, pm->msg, msize);
594 session->pending_messages = pm->next;
595 if (pm->transmit_cont != NULL)
596 pm->transmit_cont (pm->transmit_cont_cls,
597 &session->target, GNUNET_OK);
599 session->gen_time[session->out_msg_counter % ACK_LOG_SIZE]
600 = GNUNET_TIME_absolute_get ();
602 process_pending_messages (session);
604 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
605 "tcp", "Transmitting %u bytes\n", ret);
612 * If we have pending messages, ask the server to
613 * transmit them (schedule the respective tasks, etc.)
615 * @param session for which session should we do this
618 process_pending_messages (struct Session *session)
620 GNUNET_assert (session->client != NULL);
621 if (session->pending_messages == NULL)
623 if (session->transmit_handle != NULL)
625 session->transmit_handle
626 = GNUNET_SERVER_notify_transmit_ready (session->client,
627 ntohs (session->pending_messages->
629 (session->pending_messages->
630 is_welcome ? 0 : sizeof (struct
632 GNUNET_TIME_absolute_get_remaining
633 (session->pending_messages[0].
634 timeout), &do_transmit, session);
640 * Create a new session connecting to the specified
641 * target at the specified address. The session will
642 * be used to verify an address in a HELLO and should
643 * not expect to receive a WELCOME.
646 * @param target peer to connect to
647 * @param addrlen IPv4 or IPv6
648 * @param addr either struct sockaddr_in or struct sockaddr_in6
649 * @return NULL connection failed / invalid address
651 static struct Session *
652 connect_and_create_validation_session (struct Plugin *plugin,
653 const struct GNUNET_PeerIdentity
654 *target, const void *addr,
657 struct GNUNET_SERVER_Client *client;
658 struct GNUNET_CONNECTION_Handle *conn;
659 struct Session *session;
662 if (addrlen == sizeof (struct sockaddr_in))
664 else if (addrlen == sizeof (struct sockaddr_in6))
669 return NULL; /* invalid address */
671 conn = GNUNET_CONNECTION_create_from_sockaddr (plugin->env->sched,
675 GNUNET_SERVER_MAX_MESSAGE_SIZE);
679 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
681 "Failed to create connection to peer at `%s'.\n",
682 GNUNET_a2s (addr, addrlen));
686 client = GNUNET_SERVER_connect_socket (plugin->server, conn);
687 GNUNET_assert (client != NULL);
688 session = create_session (plugin, target, client, addr, addrlen);
690 GNUNET_free (session->pending_messages);
691 session->pending_messages = NULL;
692 session->connect_alen = addrlen;
693 session->connect_addr = GNUNET_malloc (addrlen);
694 session->expecting_welcome = GNUNET_SYSERR;
695 memcpy (session->connect_addr, addr, addrlen);
697 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
699 "Creating new session %p with `%s' for `%4s' based on `%s' request.\n",
701 GNUNET_a2s (addr, addrlen),
702 GNUNET_i2s (&session->target), "VALIDATE");
709 * Function that can be used by the transport service to validate that
710 * another peer is reachable at a particular address (even if we
711 * already have a connection to this peer, this function is required
712 * to establish a new one).
715 * @param target who should receive this message
716 * @param challenge challenge code to use
717 * @param addrlen length of the address
718 * @param addr the address
719 * @param timeout how long should we try to transmit these?
720 * @return GNUNET_OK if the transmission has been scheduled
723 tcp_plugin_validate (void *cls,
724 const struct GNUNET_PeerIdentity *target,
726 struct GNUNET_TIME_Relative timeout,
727 const void *addr, size_t addrlen)
729 struct Plugin *plugin = cls;
730 struct Session *session;
731 struct PendingMessage *pm;
732 struct ValidationChallengeMessage *vcm;
735 connect_and_create_validation_session (plugin, target, addr, addrlen);
739 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
740 "tcp", "Failed to create fresh session.\n");
742 return GNUNET_SYSERR;
744 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
745 sizeof (struct ValidationChallengeMessage) + addrlen);
746 pm->msg = (struct GNUNET_MessageHeader *) &pm[1];
747 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
748 pm->is_welcome = GNUNET_YES;
749 vcm = (struct ValidationChallengeMessage *) &pm[1];
751 htons (sizeof (struct ValidationChallengeMessage) + addrlen);
752 vcm->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_PING);
753 vcm->challenge = htonl (challenge);
754 vcm->target = *target;
755 memcpy (&vcm[1], addr, addrlen);
756 GNUNET_assert (session->pending_messages == NULL);
757 session->pending_messages = pm;
758 process_pending_messages (session);
764 * Functions with this signature are called whenever we need
765 * to close a session due to a disconnect or failure to
766 * establish a connection.
768 * @param session session to close down
771 disconnect_session (struct Session *session)
773 struct Session *prev;
775 struct PendingMessage *pm;
778 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
780 "Disconnecting from `%4s' at %s (session %p).\n",
781 GNUNET_i2s (&session->target),
782 (session->connect_addr != NULL) ?
783 GNUNET_a2s (session->connect_addr,
784 session->connect_alen) : "*", session);
786 /* remove from session list */
788 pos = session->plugin->sessions;
789 while (pos != session)
795 session->plugin->sessions = session->next;
797 prev->next = session->next;
799 if (session->ic != NULL)
801 GNUNET_PEERINFO_iterate_cancel (session->ic);
804 if (session->transmit_handle != NULL)
806 GNUNET_CONNECTION_notify_transmit_ready_cancel (session->
808 session->transmit_handle = NULL;
810 while (NULL != (pm = session->pending_messages))
813 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
815 pm->transmit_cont != NULL
816 ? "Could not deliver message of type %u to `%4s'.\n"
818 "Could not deliver message of type %u to `%4s', notifying.\n",
819 ntohs (pm->msg->type), GNUNET_i2s (&session->target));
821 session->pending_messages = pm->next;
822 if (NULL != pm->transmit_cont)
823 pm->transmit_cont (pm->transmit_cont_cls,
824 &session->target, GNUNET_SYSERR);
827 if (GNUNET_NO == session->expecting_welcome)
830 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
832 "Notifying transport service about loss of data connection with `%4s'.\n",
833 GNUNET_i2s (&session->target));
835 /* Data session that actually went past the
836 initial handshake; transport service may
837 know about this one, so we need to
838 notify transport service about disconnect */
839 session->plugin->env->receive (session->plugin->env->cls,
840 GNUNET_TIME_UNIT_ZERO,
841 &session->target, NULL);
843 if (session->client != NULL)
845 GNUNET_SERVER_client_drop (session->client);
846 session->client = NULL;
848 GNUNET_free_non_null (session->connect_addr);
849 GNUNET_free (session);
854 * Iterator callback to go over all addresses. If we get
855 * a TCP address, increment the counter
857 * @param cls closure, points to the counter
858 * @param tname name of the transport
859 * @param expiration expiration time
860 * @param addr the address
861 * @param addrlen length of the address
862 * @return GNUNET_OK to keep the address,
863 * GNUNET_NO to delete it from the HELLO
864 * GNUNET_SYSERR to stop iterating (but keep current address)
867 count_tcp_addresses (void *cls,
869 struct GNUNET_TIME_Absolute expiration,
870 const void *addr, size_t addrlen)
872 unsigned int *counter = cls;
874 if (0 != strcmp (tname, "tcp"))
875 return GNUNET_OK; /* not one of ours */
877 return GNUNET_OK; /* failed to connect */
881 struct ConnectContext
883 struct Plugin *plugin;
885 struct GNUNET_CONNECTION_Handle *sa;
887 struct PendingMessage *welcome;
894 * Iterator callback to go over all addresses. If we get
895 * the "pos" TCP address, try to connect to it.
898 * @param tname name of the transport
899 * @param expiration expiration time
900 * @param addrlen length of the address
901 * @param addr the address
902 * @return GNUNET_OK to keep the address,
903 * GNUNET_NO to delete it from the HELLO
904 * GNUNET_SYSERR to stop iterating (but keep current address)
907 try_connect_to_address (void *cls,
909 struct GNUNET_TIME_Absolute expiration,
910 const void *addr, size_t addrlen)
912 struct ConnectContext *cc = cls;
915 if (0 != strcmp (tname, "tcp"))
916 return GNUNET_OK; /* not one of ours */
917 if (sizeof (struct sockaddr_in) == addrlen)
919 else if (sizeof (struct sockaddr_in6) == addrlen)
923 /* not a valid address */
929 cc->welcome = create_welcome (addrlen, addr, cc->plugin);
931 GNUNET_CONNECTION_create_from_sockaddr (cc->plugin->env->sched,
933 GNUNET_SERVER_MAX_MESSAGE_SIZE);
935 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
937 "Connecting using address %s.\n",
938 GNUNET_a2s (addr, addrlen));
940 return GNUNET_SYSERR;
942 return GNUNET_OK; /* failed to connect */
947 * Type of an iterator over the hosts. Note that each
948 * host will be called with each available protocol.
951 * @param peer id of the peer, NULL for last call
952 * @param hello hello message for the peer (can be NULL)
953 * @param trust amount of trust we have in the peer
956 session_try_connect (void *cls,
957 const struct GNUNET_PeerIdentity *peer,
958 const struct GNUNET_HELLO_Message *hello, uint32_t trust)
960 struct Session *session = cls;
962 struct ConnectContext cctx;
963 struct PendingMessage *pm;
968 /* last call, destroy session if we are still not
970 if (session->client != NULL)
973 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
975 "Now connected to `%4s', now processing messages.\n",
976 GNUNET_i2s (&session->target));
978 process_pending_messages (session);
983 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
985 "Failed to connect to `%4s' (no working `%s'), closing session.\n",
986 GNUNET_i2s (&session->target), "HELLO");
988 disconnect_session (session);
992 if ((hello == NULL) || (session->client != NULL))
994 GNUNET_break (0); /* should this ever happen!? */
998 GNUNET_HELLO_iterate_addresses (hello,
999 GNUNET_NO, &count_tcp_addresses, &count);
1003 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1005 "Asked to connect to `%4s', but have no addresses to try.\n",
1006 GNUNET_i2s (&session->target));
1010 cctx.plugin = session->plugin;
1012 cctx.welcome = NULL;
1013 cctx.pos = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, count);
1014 GNUNET_HELLO_iterate_addresses (hello,
1015 GNUNET_NO, &try_connect_to_address, &cctx);
1016 if (cctx.sa == NULL)
1019 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1021 "Asked to connect, but all addresses failed.\n");
1023 GNUNET_free_non_null (cctx.welcome);
1026 session->client = GNUNET_SERVER_connect_socket (session->plugin->server,
1029 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1030 "Connected to `%4s' for session %p\n",
1031 GNUNET_i2s (&session->target), session->client);
1033 if (session->client == NULL)
1035 GNUNET_break (0); /* how could this happen? */
1036 GNUNET_free_non_null (cctx.welcome);
1041 pm->next = session->pending_messages;
1042 session->pending_messages = pm;
1044 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1046 "Connected to `%4s', now sending `%s' message.\n",
1047 GNUNET_i2s (&session->target), "WELCOME");
1053 * Function that can be used by the transport service to transmit
1054 * a message using the plugin.
1056 * @param cls closure
1057 * @param service_context value passed to the transport-service
1058 * to identify the neighbour
1059 * @param target who should receive this message
1060 * @param priority how important is the message
1061 * @param msg the message to transmit
1062 * @param timeout when should we time out (give up) if we can not transmit?
1063 * @param cont continuation to call once the message has
1064 * been transmitted (or if the transport is ready
1065 * for the next transmission call; or if the
1066 * peer disconnected...)
1067 * @param cont_cls closure for cont
1070 tcp_plugin_send (void *cls,
1071 const struct GNUNET_PeerIdentity *target,
1072 unsigned int priority,
1073 const struct GNUNET_MessageHeader *msg,
1074 struct GNUNET_TIME_Relative timeout,
1075 GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
1077 struct Plugin *plugin = cls;
1078 struct Session *session;
1079 struct PendingMessage *pm;
1080 struct PendingMessage *pme;
1082 session = find_session_by_target (plugin, target);
1083 pm = GNUNET_malloc (sizeof (struct PendingMessage) + ntohs (msg->size));
1084 pm->msg = (struct GNUNET_MessageHeader *) &pm[1];
1085 memcpy (pm->msg, msg, ntohs (msg->size));
1086 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1087 pm->transmit_cont = cont;
1088 pm->transmit_cont_cls = cont_cls;
1089 if (session == NULL)
1091 session = GNUNET_malloc (sizeof (struct Session));
1093 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1095 "Asked to transmit, creating fresh session %p.\n",
1098 session->next = plugin->sessions;
1099 plugin->sessions = session;
1100 session->plugin = plugin;
1101 session->target = *target;
1102 session->last_quota_update = GNUNET_TIME_absolute_get ();
1103 session->quota_in = plugin->env->default_quota_in;
1104 session->expecting_welcome = GNUNET_YES;
1105 session->pending_messages = pm;
1106 session->ic = GNUNET_PEERINFO_iterate (plugin->env->cfg,
1109 0, timeout, &session_try_connect,
1113 GNUNET_assert (session != NULL);
1114 GNUNET_assert (session->client != NULL);
1115 /* append pm to pending_messages list */
1116 pme = session->pending_messages;
1119 session->pending_messages = pm;
1123 while (NULL != pme->next)
1128 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1129 "tcp", "Asked to transmit, added message to list.\n");
1131 process_pending_messages (session);
1137 * Function that can be called to force a disconnect from the
1138 * specified neighbour. This should also cancel all previously
1139 * scheduled transmissions. Obviously the transmission may have been
1140 * partially completed already, which is OK. The plugin is supposed
1141 * to close the connection (if applicable) and no longer call the
1142 * transmit continuation(s).
1144 * Finally, plugin MUST NOT call the services's receive function to
1145 * notify the service that the connection to the specified target was
1146 * closed after a getting this call.
1148 * @param cls closure
1149 * @param target peer for which the last transmission is
1153 tcp_plugin_disconnect (void *cls, const struct GNUNET_PeerIdentity *target)
1155 struct Plugin *plugin = cls;
1156 struct Session *session;
1157 struct PendingMessage *pm;
1159 session = find_session_by_target (plugin, target);
1160 if (session == NULL)
1166 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1168 "Asked to cancel session with `%4s'\n",
1169 GNUNET_i2s (target));
1171 pm = session->pending_messages;
1174 pm->transmit_cont = NULL;
1175 pm->transmit_cont_cls = NULL;
1178 if (session->client != NULL)
1180 GNUNET_SERVER_client_drop (session->client);
1181 session->client = NULL;
1183 /* rest of the clean-up of the session will be done as part of
1184 disconnect_notify which should be triggered any time now
1185 (or which may be triggering this call in the first place) */
1189 struct PrettyPrinterContext
1191 GNUNET_TRANSPORT_AddressStringCallback asc;
1198 * Append our port and forward the result.
1201 append_port (void *cls, const char *hostname)
1203 struct PrettyPrinterContext *ppc = cls;
1206 if (hostname == NULL)
1208 ppc->asc (ppc->asc_cls, NULL);
1212 GNUNET_asprintf (&ret, "%s:%d", hostname, ppc->port);
1213 ppc->asc (ppc->asc_cls, ret);
1219 * Convert the transports address to a nice, human-readable
1222 * @param cls closure
1223 * @param type name of the transport that generated the address
1224 * @param addr one of the addresses of the host, NULL for the last address
1225 * the specific address format depends on the transport
1226 * @param addrlen length of the address
1227 * @param numeric should (IP) addresses be displayed in numeric form?
1228 * @param timeout after how long should we give up?
1229 * @param asc function to call on each string
1230 * @param asc_cls closure for asc
1233 tcp_plugin_address_pretty_printer (void *cls,
1238 struct GNUNET_TIME_Relative timeout,
1239 GNUNET_TRANSPORT_AddressStringCallback asc,
1242 struct Plugin *plugin = cls;
1243 const struct sockaddr_in *v4;
1244 const struct sockaddr_in6 *v6;
1245 struct PrettyPrinterContext *ppc;
1247 if ((addrlen != sizeof (struct sockaddr_in)) &&
1248 (addrlen != sizeof (struct sockaddr_in6)))
1250 /* invalid address */
1251 GNUNET_break_op (0);
1252 asc (asc_cls, NULL);
1255 ppc = GNUNET_malloc (sizeof (struct PrettyPrinterContext));
1257 ppc->asc_cls = asc_cls;
1258 if (addrlen == sizeof (struct sockaddr_in))
1260 v4 = (const struct sockaddr_in *) addr;
1261 ppc->port = ntohs (v4->sin_port);
1265 v6 = (const struct sockaddr_in6 *) addr;
1266 ppc->port = ntohs (v6->sin6_port);
1269 GNUNET_RESOLVER_hostname_get (plugin->env->sched,
1273 !numeric, timeout, &append_port, ppc);
1278 * Update the last-received and bandwidth quota values
1281 * @param session session to update
1282 * @param force set to GNUNET_YES if we should update even
1283 * though the minimum refresh time has not yet expired
1286 update_quota (struct Session *session, int force)
1288 struct GNUNET_TIME_Absolute now;
1289 unsigned long long delta;
1290 unsigned long long total_allowed;
1291 unsigned long long total_remaining;
1293 now = GNUNET_TIME_absolute_get ();
1294 delta = now.value - session->last_quota_update.value;
1295 if ((delta < MIN_QUOTA_REFRESH_TIME) && (!force))
1296 return; /* too early, not enough data */
1298 total_allowed = session->quota_in * delta;
1299 if (total_allowed > session->last_received)
1301 /* got less than acceptable */
1302 total_remaining = total_allowed - session->last_received;
1303 session->last_received = 0;
1304 delta = total_remaining / session->quota_in; /* bonus seconds */
1305 if (delta > MAX_BANDWIDTH_CARRY)
1306 delta = MAX_BANDWIDTH_CARRY; /* limit amount of carry-over */
1310 /* got more than acceptable */
1311 session->last_received -= total_allowed;
1314 session->last_quota_update.value = now.value - delta;
1319 * Set a quota for receiving data from the given peer; this is a
1320 * per-transport limit. The transport should limit its read/select
1321 * calls to stay below the quota (in terms of incoming data).
1323 * @param cls closure
1324 * @param target the peer for whom the quota is given
1325 * @param quota_in quota for receiving/sending data in bytes per ms
1328 tcp_plugin_set_receive_quota (void *cls,
1329 const struct GNUNET_PeerIdentity *target,
1332 struct Plugin *plugin = cls;
1333 struct Session *session;
1335 session = find_session_by_target (plugin, target);
1336 if (session == NULL)
1337 return; /* peer must have disconnected, ignore */
1338 if (session->quota_in != quota_in)
1340 update_quota (session, GNUNET_YES);
1341 if (session->quota_in > quota_in)
1342 session->last_quota_update = GNUNET_TIME_absolute_get ();
1343 session->quota_in = quota_in;
1349 * Check if the given port is plausible (must be either
1350 * our listen port or our advertised port). If it is
1351 * neither, we return one of these two ports at random.
1353 * @return either in_port or a more plausible port
1356 check_port (struct Plugin *plugin, uint16_t in_port)
1358 if ((in_port == plugin->adv_port) || (in_port == plugin->open_port))
1360 return (GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1362 ? plugin->open_port : plugin->adv_port;
1367 * Another peer has suggested an address for this
1368 * peer and transport plugin. Check that this could be a valid
1369 * address. If so, consider adding it to the list
1372 * @param cls closure
1373 * @param addr pointer to the address
1374 * @param addrlen length of addr
1375 * @return GNUNET_OK if this is a plausible address for this peer
1379 tcp_plugin_address_suggested (void *cls, const void *addr, size_t addrlen)
1381 struct Plugin *plugin = cls;
1382 char buf[sizeof (struct sockaddr_in6)];
1383 struct sockaddr_in *v4;
1384 struct sockaddr_in6 *v6;
1386 if ((addrlen != sizeof (struct sockaddr_in)) &&
1387 (addrlen != sizeof (struct sockaddr_in6)))
1389 GNUNET_break_op (0);
1390 return GNUNET_SYSERR;
1392 memcpy (buf, addr, sizeof (struct sockaddr_in6));
1393 if (addrlen == sizeof (struct sockaddr_in))
1395 v4 = (struct sockaddr_in *) buf;
1396 v4->sin_port = htons (check_port (plugin, ntohs (v4->sin_port)));
1400 v6 = (struct sockaddr_in6 *) buf;
1401 v6->sin6_port = htons (check_port (plugin, ntohs (v6->sin6_port)));
1404 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1406 "Informing transport service about my address `%s'.\n",
1407 GNUNET_a2s (addr, addrlen));
1409 plugin->env->notify_address (plugin->env->cls,
1411 buf, addrlen, LEARNED_ADDRESS_EXPIRATION);
1417 * Send a validation challenge response.
1420 send_vcr (void *cls, size_t size, void *buf)
1422 struct ValidationChallengeResponse *vcr = cls;
1430 msize = ntohs (vcr->header.size);
1431 GNUNET_assert (size >= msize);
1432 memcpy (buf, vcr, msize);
1439 * We've received a PING from this peer via TCP.
1440 * Send back our PONG.
1442 * @param cls closure
1443 * @param client identification of the client
1444 * @param message the actual message
1447 handle_tcp_ping (void *cls,
1448 struct GNUNET_SERVER_Client *client,
1449 const struct GNUNET_MessageHeader *message)
1451 struct Plugin *plugin = cls;
1452 const struct ValidationChallengeMessage *vcm;
1453 struct ValidationChallengeResponse *vcr;
1460 GNUNET_SERVER_client_get_address (client, (void **) &addr, &addrlen))
1462 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1463 "Processing `%s' from `%s'\n",
1464 "PING", GNUNET_a2s (addr, addrlen));
1468 msize = ntohs (message->size);
1469 if (msize < sizeof (struct ValidationChallengeMessage))
1471 GNUNET_break_op (0);
1472 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1475 vcm = (const struct ValidationChallengeMessage *) message;
1476 if (0 != memcmp (&vcm->target,
1477 plugin->env->my_identity,
1478 sizeof (struct GNUNET_PeerIdentity)))
1480 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1481 _("Received `%s' message not destined for me!\n"), "PING");
1482 /* TODO: call statistics */
1483 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1486 msize -= sizeof (struct ValidationChallengeMessage);
1487 if (GNUNET_OK != tcp_plugin_address_suggested (plugin, &vcm[1], msize))
1489 GNUNET_break_op (0);
1490 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1493 if (GNUNET_OK != GNUNET_SERVER_client_get_address (client, &addr, &addrlen))
1496 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1499 vcr = GNUNET_malloc (sizeof (struct ValidationChallengeResponse) + addrlen);
1501 htons (sizeof (struct ValidationChallengeResponse) + addrlen);
1502 vcr->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_PONG);
1504 htonl (sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
1506 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded) + addrlen);
1507 vcr->purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_TCP_PING);
1508 vcr->challenge = vcm->challenge;
1509 vcr->signer = *plugin->env->my_public_key;
1510 memcpy (&vcr[1], addr, addrlen);
1511 GNUNET_assert (GNUNET_OK ==
1512 GNUNET_CRYPTO_rsa_sign (plugin->env->my_private_key,
1513 &vcr->purpose, &vcr->signature));
1515 GNUNET_assert (GNUNET_OK ==
1516 GNUNET_CRYPTO_rsa_verify
1517 (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_TCP_PING,
1519 &vcr->signature, plugin->env->my_public_key));
1523 GNUNET_SERVER_notify_transmit_ready (client,
1525 ValidationChallengeResponse)
1527 GNUNET_TIME_UNIT_SECONDS,
1533 /* after a PING, we always close the connection */
1534 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1539 * Handle PONG-message.
1541 * @param cls handle for this plugin
1542 * @param client from where did we receive the PONG
1543 * @param message the actual message
1546 handle_tcp_pong (void *cls,
1547 struct GNUNET_SERVER_Client *client,
1548 const struct GNUNET_MessageHeader *message)
1550 struct Plugin *plugin = cls;
1551 const struct ValidationChallengeResponse *vcr;
1552 struct GNUNET_PeerIdentity peer;
1555 const struct sockaddr *addr;
1556 struct sockaddr_in v4;
1557 struct sockaddr_in6 v6;
1560 struct sockaddr *claddr;
1563 GNUNET_SERVER_client_get_address (client, (void **) &claddr, &addrlen))
1565 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1566 "Processing `%s' from `%s'\n",
1567 "PONG", GNUNET_a2s (claddr, addrlen));
1568 GNUNET_free (claddr);
1571 if (ntohs (message->size) < sizeof (struct ValidationChallengeResponse))
1573 GNUNET_break_op (0);
1574 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1578 ntohs (message->size) - sizeof (struct ValidationChallengeResponse);
1579 vcr = (const struct ValidationChallengeResponse *) message;
1580 if ((ntohl (vcr->purpose.size) !=
1581 sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
1583 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded) + addrlen))
1585 GNUNET_break_op (0);
1586 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1590 GNUNET_CRYPTO_rsa_verify
1591 (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_TCP_PING,
1592 &vcr->purpose, &vcr->signature, &vcr->signer))
1594 GNUNET_break_op (0);
1595 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1598 GNUNET_CRYPTO_hash (&vcr->signer,
1599 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
1601 addr = (const struct sockaddr *) &vcr[1];
1602 if (addrlen == sizeof (struct sockaddr_in))
1604 memcpy (&v4, addr, sizeof (struct sockaddr_in));
1605 v4.sin_port = htons (check_port (plugin, ntohs (v4.sin_port)));
1606 sender_addr = GNUNET_strdup (GNUNET_a2s ((const struct sockaddr *) &v4,
1609 else if (addrlen == sizeof (struct sockaddr_in6))
1611 memcpy (&v6, addr, sizeof (struct sockaddr_in6));
1612 v6.sin6_port = htons (check_port (plugin, ntohs (v6.sin6_port)));
1613 sender_addr = GNUNET_strdup (GNUNET_a2s ((const struct sockaddr *) &v6,
1618 GNUNET_break_op (0);
1619 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1622 plugin->env->notify_validation (plugin->env->cls,
1624 &peer, ntohl (vcr->challenge), sender_addr);
1625 GNUNET_free (sender_addr);
1626 /* after a PONG, we always close the connection */
1627 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1632 * We've received a welcome from this peer via TCP.
1633 * Possibly create a fresh client record and send back
1636 * @param cls closure
1637 * @param client identification of the client
1638 * @param message the actual message
1641 handle_tcp_welcome (void *cls,
1642 struct GNUNET_SERVER_Client *client,
1643 const struct GNUNET_MessageHeader *message)
1645 struct Plugin *plugin = cls;
1646 struct Session *session_c;
1647 const struct WelcomeMessage *wm;
1652 const struct sockaddr *addr;
1654 msize = ntohs (message->size);
1655 if (msize < sizeof (struct WelcomeMessage))
1657 GNUNET_break_op (0);
1658 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1661 wm = (const struct WelcomeMessage *) message;
1663 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1665 "Received `%s' message from `%4s/%p'.\n", "WELCOME",
1666 GNUNET_i2s (&wm->clientIdentity), client);
1668 session_c = find_session_by_client (plugin, client);
1669 if (session_c == NULL)
1672 GNUNET_SERVER_client_get_address (client, &vaddr, &alen);
1673 GNUNET_SERVER_client_keep (client);
1674 session_c = create_session (plugin,
1675 &wm->clientIdentity, client, vaddr, alen);
1677 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1679 "Creating new session %p for incoming `%s' message.\n",
1680 session_c, "WELCOME");
1682 GNUNET_free_non_null (vaddr);
1683 process_pending_messages (session_c);
1685 if (session_c->expecting_welcome != GNUNET_YES)
1687 GNUNET_break_op (0);
1688 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1691 session_c->expecting_welcome = GNUNET_NO;
1692 if (0 < (addrlen = msize - sizeof (struct WelcomeMessage)))
1694 addr = (const struct sockaddr *) &wm[1];
1695 tcp_plugin_address_suggested (plugin, addr, addrlen);
1697 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1702 * Calculate how long we should delay reading from the TCP socket to
1703 * ensure that we stay within our bandwidth limits (push back).
1705 * @param session for which client should this be calculated
1707 static struct GNUNET_TIME_Relative
1708 calculate_throttle_delay (struct Session *session)
1710 struct GNUNET_TIME_Relative ret;
1711 struct GNUNET_TIME_Absolute now;
1716 now = GNUNET_TIME_absolute_get ();
1717 del = now.value - session->last_quota_update.value;
1718 if (del > MAX_BANDWIDTH_CARRY)
1720 update_quota (session, GNUNET_YES);
1721 del = now.value - session->last_quota_update.value;
1722 GNUNET_assert (del <= MAX_BANDWIDTH_CARRY);
1724 if (session->quota_in == 0)
1725 session->quota_in = 1; /* avoid divison by zero */
1726 avail = del * session->quota_in;
1727 if (avail > session->last_received)
1728 return GNUNET_TIME_UNIT_ZERO; /* can receive right now */
1729 excess = session->last_received - avail;
1730 ret.value = excess / session->quota_in;
1736 * Task to signal the server that we can continue
1737 * receiving from the TCP client now.
1740 delayed_done (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1742 struct Session *session = cls;
1743 GNUNET_SERVER_receive_done (session->client, GNUNET_OK);
1748 * We've received data for this peer via TCP. Unbox,
1749 * compute latency and forward.
1751 * @param cls closure
1752 * @param client identification of the client
1753 * @param message the actual message
1756 handle_tcp_data (void *cls,
1757 struct GNUNET_SERVER_Client *client,
1758 const struct GNUNET_MessageHeader *message)
1760 struct Plugin *plugin = cls;
1761 struct Session *session;
1762 const struct DataMessage *dm;
1764 const struct GNUNET_MessageHeader *msg;
1765 struct GNUNET_TIME_Relative latency;
1766 struct GNUNET_TIME_Absolute ttime;
1767 struct GNUNET_TIME_Absolute now;
1768 struct GNUNET_TIME_Relative delay;
1771 msize = ntohs (message->size);
1773 sizeof (struct DataMessage) + sizeof (struct GNUNET_MessageHeader)))
1775 GNUNET_break_op (0);
1776 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1779 session = find_session_by_client (plugin, client);
1780 if ((NULL == session) || (GNUNET_NO != session->expecting_welcome))
1782 GNUNET_break_op (0);
1783 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1787 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1788 "tcp", "Receiving %u bytes from `%4s'.\n",
1789 msize, GNUNET_i2s (&session->target));
1791 dm = (const struct DataMessage *) message;
1792 session->max_in_msg_counter = GNUNET_MAX (session->max_in_msg_counter,
1793 GNUNET_ntohll (dm->ack_out));
1794 msg = (const struct GNUNET_MessageHeader *) &dm[1];
1795 if (msize != sizeof (struct DataMessage) + ntohs (msg->size))
1797 GNUNET_break_op (0);
1798 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1801 /* estimate latency */
1802 ack_in = GNUNET_ntohll (dm->ack_in);
1803 if ((ack_in <= session->out_msg_counter) &&
1804 (session->out_msg_counter - ack_in < ACK_LOG_SIZE))
1806 delay = GNUNET_TIME_relative_ntoh (dm->delay);
1807 ttime = session->gen_time[ack_in % ACK_LOG_SIZE];
1808 now = GNUNET_TIME_absolute_get ();
1809 if (delay.value > now.value - ttime.value)
1810 delay.value = 0; /* not plausible */
1811 /* update (round-trip) latency using ageing; we
1812 use 7:1 so that we can reasonably quickly react
1813 to changes, but not so fast that latency is largely
1815 session->latency_estimate
1816 = ((7 * session->latency_estimate) +
1817 (now.value - ttime.value - delay.value)) / 8;
1819 latency.value = (uint64_t) session->latency_estimate;
1822 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1824 "Forwarding data of type %u to transport service.\n",
1827 plugin->env->receive (plugin->env->cls, latency, &session->target, msg);
1828 /* update bandwidth used */
1829 session->last_received += msize;
1830 update_quota (session, GNUNET_NO);
1832 delay = calculate_throttle_delay (session);
1833 if (delay.value == 0)
1834 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1836 GNUNET_SCHEDULER_add_delayed (session->plugin->env->sched,
1837 delay, &delayed_done, session);
1842 * Handlers for the various TCP messages.
1844 static struct GNUNET_SERVER_MessageHandler my_handlers[] = {
1845 {&handle_tcp_ping, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_PING, 0},
1846 {&handle_tcp_pong, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_PONG, 0},
1847 {&handle_tcp_welcome, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME, 0},
1848 {&handle_tcp_data, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_DATA, 0},
1854 create_tcp_handlers (struct Plugin *plugin)
1857 plugin->handlers = GNUNET_malloc (sizeof (my_handlers));
1858 memcpy (plugin->handlers, my_handlers, sizeof (my_handlers));
1861 sizeof (my_handlers) / sizeof (struct GNUNET_SERVER_MessageHandler);
1863 plugin->handlers[i].callback_cls = plugin;
1864 GNUNET_SERVER_add_handlers (plugin->server, plugin->handlers);
1869 * Functions with this signature are called whenever a peer
1870 * is disconnected on the network level.
1872 * @param cls closure
1873 * @param client identification of the client
1876 disconnect_notify (void *cls, struct GNUNET_SERVER_Client *client)
1878 struct Plugin *plugin = cls;
1879 struct Session *session;
1881 session = find_session_by_client (plugin, client);
1882 if (session == NULL)
1883 return; /* unknown, nothing to do */
1885 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1887 "Destroying session of `%4s' with %s (%p) due to network-level disconnect.\n",
1888 GNUNET_i2s (&session->target),
1889 (session->connect_addr != NULL) ?
1890 GNUNET_a2s (session->connect_addr,
1891 session->connect_alen) : "*", client);
1893 disconnect_session (session);
1898 * Add the IP of our network interface to the list of
1899 * our external IP addresses.
1902 process_interfaces (void *cls,
1905 const struct sockaddr *addr, socklen_t addrlen)
1907 struct Plugin *plugin = cls;
1909 struct sockaddr_in *v4;
1910 struct sockaddr_in6 *v6;
1912 af = addr->sa_family;
1915 v4 = (struct sockaddr_in *) addr;
1916 v4->sin_port = htons (plugin->adv_port);
1920 GNUNET_assert (af == AF_INET6);
1921 v6 = (struct sockaddr_in6 *) addr;
1922 v6->sin6_port = htons (plugin->adv_port);
1924 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO |
1925 GNUNET_ERROR_TYPE_BULK,
1926 "tcp", _("Found address `%s' (%s)\n"),
1927 GNUNET_a2s (addr, addrlen), name);
1928 plugin->env->notify_address (plugin->env->cls,
1930 addr, addrlen, GNUNET_TIME_UNIT_FOREVER_REL);
1936 * Function called by the resolver for each address obtained from DNS
1937 * for our own hostname. Add the addresses to the list of our
1938 * external IP addresses.
1940 * @param cls closure
1941 * @param addr one of the addresses of the host, NULL for the last address
1942 * @param addrlen length of the address
1945 process_hostname_ips (void *cls,
1946 const struct sockaddr *addr, socklen_t addrlen)
1948 struct Plugin *plugin = cls;
1952 plugin->hostname_dns = NULL;
1955 process_interfaces (plugin, "<hostname>", GNUNET_YES, addr, addrlen);
1960 * Entry point for the plugin.
1963 libgnunet_plugin_transport_tcp_init (void *cls)
1965 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
1966 struct GNUNET_TRANSPORT_PluginFunctions *api;
1967 struct Plugin *plugin;
1968 struct GNUNET_SERVICE_Context *service;
1969 unsigned long long aport;
1970 unsigned long long bport;
1972 service = GNUNET_SERVICE_start ("transport-tcp", env->sched, env->cfg);
1973 if (service == NULL)
1975 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING,
1978 ("Failed to start service for `%s' transport plugin.\n"),
1984 GNUNET_CONFIGURATION_get_value_number (env->cfg,
1990 GNUNET_CONFIGURATION_get_value_number (env->cfg,
1993 &aport)) && (aport > 65535)))
1995 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
1998 ("Require valid port number for service `%s' in configuration!\n"),
2000 GNUNET_SERVICE_stop (service);
2005 plugin = GNUNET_malloc (sizeof (struct Plugin));
2006 plugin->open_port = bport;
2007 plugin->adv_port = aport;
2009 plugin->lsock = NULL;
2010 plugin->statistics = NULL;
2011 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
2013 api->validate = &tcp_plugin_validate;
2014 api->send = &tcp_plugin_send;
2015 api->disconnect = &tcp_plugin_disconnect;
2016 api->address_pretty_printer = &tcp_plugin_address_pretty_printer;
2017 api->set_receive_quota = &tcp_plugin_set_receive_quota;
2018 api->address_suggested = &tcp_plugin_address_suggested;
2019 api->cost_estimate = 42; /* TODO: ATS */
2020 plugin->service = service;
2021 plugin->server = GNUNET_SERVICE_get_server (service);
2022 create_tcp_handlers (plugin);
2023 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2024 "tcp", _("TCP transport listening on port %llu\n"), bport);
2026 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2029 ("TCP transport advertises itself as being on port %llu\n"),
2031 GNUNET_SERVER_disconnect_notify (plugin->server, &disconnect_notify,
2033 GNUNET_OS_network_interfaces_list (&process_interfaces, plugin);
2034 plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (env->sched,
2037 HOSTNAME_RESOLVE_TIMEOUT,
2038 &process_hostname_ips,
2045 * Exit point from the plugin.
2048 libgnunet_plugin_transport_tcp_done (void *cls)
2050 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
2051 struct Plugin *plugin = api->cls;
2052 struct Session *session;
2054 while (NULL != (session = plugin->sessions))
2055 disconnect_session (session);
2056 if (NULL != plugin->hostname_dns)
2058 GNUNET_RESOLVER_request_cancel (plugin->hostname_dns);
2059 plugin->hostname_dns = NULL;
2061 GNUNET_SERVICE_stop (plugin->service);
2062 GNUNET_free (plugin->handlers);
2063 GNUNET_free (plugin);
2068 /* end of plugin_transport_tcp.c */