2 This file is part of GNUnet
3 (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
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13 General Public License for more details.
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21 * @file transport/plugin_transport_tcp.c
22 * @brief Implementation of the TCP transport service
23 * @author Christian Grothoff
26 #include "gnunet_hello_lib.h"
27 #include "gnunet_constants.h"
28 #include "gnunet_connection_lib.h"
29 #include "gnunet_container_lib.h"
30 #include "gnunet_nat_lib.h"
31 #include "gnunet_os_lib.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 "gnunet_transport_plugin.h"
40 #include "transport.h"
42 #define DEBUG_TCP GNUNET_NO
44 #define DEBUG_TCP_NAT GNUNET_NO
47 * Initial handshake message for a session.
52 * Type is GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME.
54 struct GNUNET_MessageHeader header;
57 * Identity of the node connecting (TCP client)
59 struct GNUNET_PeerIdentity clientIdentity;
65 * Basically a WELCOME message, but with the purpose
66 * of giving the waiting peer a client handle to use
68 struct TCP_NAT_ProbeMessage
71 * Type is GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE.
73 struct GNUNET_MessageHeader header;
76 * Identity of the sender of the message.
78 struct GNUNET_PeerIdentity clientIdentity;
84 * Context for sending a NAT probe via TCP.
86 struct TCPProbeContext
90 * Active probes are kept in a DLL.
92 struct TCPProbeContext *next;
95 * Active probes are kept in a DLL.
97 struct TCPProbeContext *prev;
102 struct GNUNET_CONNECTION_Handle *sock;
105 * Message to be sent.
107 struct TCP_NAT_ProbeMessage message;
110 * Handle to the transmission.
112 struct GNUNET_CONNECTION_TransmitHandle *transmit_handle;
115 * Transport plugin handle.
117 struct Plugin *plugin;
122 * Network format for IPv4 addresses.
124 struct IPv4TcpAddress
127 * IPv4 address, in network byte order.
129 uint32_t ipv4_addr GNUNET_PACKED;
132 * Port number, in network byte order.
134 uint16_t t4_port GNUNET_PACKED;
140 * Network format for IPv6 addresses.
142 struct IPv6TcpAddress
147 struct in6_addr ipv6_addr GNUNET_PACKED;
150 * Port number, in network byte order.
152 uint16_t t6_port GNUNET_PACKED;
158 * Encapsulation of all of the state of the plugin.
164 * Information kept for each message that is yet to
167 struct PendingMessage
171 * This is a doubly-linked list.
173 struct PendingMessage *next;
176 * This is a doubly-linked list.
178 struct PendingMessage *prev;
181 * The pending message
186 * Continuation function to call once the message
187 * has been sent. Can be NULL if there is no
188 * continuation to call.
190 GNUNET_TRANSPORT_TransmitContinuation transmit_cont;
193 * Closure for transmit_cont.
195 void *transmit_cont_cls;
198 * Timeout value for the pending message.
200 struct GNUNET_TIME_Absolute timeout;
203 * So that the gnunet-service-transport can group messages together,
204 * these pending messages need to accept a message buffer and size
205 * instead of just a GNUNET_MessageHeader.
213 * Session handle for TCP connections.
221 struct SessionHeader header;
224 * Stored in a linked list.
226 struct Session *next;
229 * Pointer to the global plugin struct.
231 struct Plugin *plugin;
234 * The client (used to identify this connection)
236 struct GNUNET_SERVER_Client *client;
239 * Messages currently pending for transmission
240 * to this peer, if any.
242 struct PendingMessage *pending_messages_head;
245 * Messages currently pending for transmission
246 * to this peer, if any.
248 struct PendingMessage *pending_messages_tail;
251 * Handle for pending transmission request.
253 struct GNUNET_CONNECTION_TransmitHandle *transmit_handle;
256 * To whom are we talking to (set to our identity
257 * if we are still waiting for the welcome message)
259 struct GNUNET_PeerIdentity target;
262 * ID of task used to delay receiving more to throttle sender.
264 GNUNET_SCHEDULER_TaskIdentifier receive_delay_task;
267 * Address of the other peer (either based on our 'connect'
268 * call or on our 'accept' call).
273 * Last activity on this connection. Used to select preferred
276 struct GNUNET_TIME_Absolute last_activity;
279 * Length of connect_addr.
284 * Are we still expecting the welcome message? (GNUNET_YES/GNUNET_NO)
286 int expecting_welcome;
289 * Was this a connection that was inbound (we accepted)? (GNUNET_YES/GNUNET_NO)
294 * Was this session created using NAT traversal?
302 * Encapsulation of all of the state of the plugin.
309 struct GNUNET_TRANSPORT_PluginEnvironment *env;
314 struct GNUNET_CONNECTION_Handle *lsock;
317 * Our handle to the NAT module.
319 struct GNUNET_NAT_Handle *nat;
322 * List of open TCP sessions.
324 struct Session *sessions;
327 * Handle to the network service.
329 struct GNUNET_SERVICE_Context *service;
332 * Handle to the server for this service.
334 struct GNUNET_SERVER_Handle *server;
337 * Copy of the handler array where the closures are
338 * set to this struct's instance.
340 struct GNUNET_SERVER_MessageHandler *handlers;
343 * Map of peers we have tried to contact behind a NAT
345 struct GNUNET_CONTAINER_MultiHashMap *nat_wait_conns;
348 * List of active TCP probes.
350 struct TCPProbeContext *probe_head;
353 * List of active TCP probes.
355 struct TCPProbeContext *probe_tail;
358 * Handle for (DYN)DNS lookup of our external IP.
360 struct GNUNET_RESOLVER_RequestHandle *ext_dns;
363 * How many more TCP sessions are we allowed to open right now?
365 unsigned long long max_connections;
368 * ID of task used to update our addresses when one expires.
370 GNUNET_SCHEDULER_TaskIdentifier address_update_task;
373 * Port that we are actually listening on.
378 * Port that the user said we would have visible to the
387 * Function to check if an inbound connection is acceptable.
388 * Mostly used to limit the total number of open connections
391 * @param cls the 'struct Plugin'
392 * @param ucred credentials, if available, otherwise NULL
393 * @param addr address
394 * @param addrlen length of address
395 * @return GNUNET_YES to allow, GNUNET_NO to deny, GNUNET_SYSERR
396 * for unknown address family (will be denied).
399 plugin_tcp_access_check (void *cls,
400 const struct GNUNET_CONNECTION_Credentials *ucred,
401 const struct sockaddr *addr,
404 struct Plugin *plugin = cls;
406 if (0 == plugin->max_connections)
408 plugin->max_connections--;
414 * Our external IP address/port mapping has changed.
416 * @param cls closure, the 'struct LocalAddrList'
417 * @param add_remove GNUNET_YES to mean the new public IP address, GNUNET_NO to mean
418 * the previous (now invalid) one
419 * @param addr either the previous or the new public IP address
420 * @param addrlen actual lenght of the address
423 tcp_nat_port_map_callback (void *cls,
425 const struct sockaddr *addr,
428 struct Plugin *plugin = cls;
429 struct IPv4TcpAddress t4;
430 struct IPv6TcpAddress t6;
434 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
436 "NPMC called with %d for address `%s'\n",
438 GNUNET_a2s (addr, addrlen));
439 /* convert 'addr' to our internal format */
440 switch (addr->sa_family)
443 GNUNET_assert (addrlen == sizeof (struct sockaddr_in));
444 t4.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
445 t4.t4_port = ((struct sockaddr_in *) addr)->sin_port;
450 GNUNET_assert (addrlen == sizeof (struct sockaddr_in6));
451 memcpy (&t6.ipv6_addr,
452 &((struct sockaddr_in6 *) addr)->sin6_addr,
453 sizeof (struct in6_addr));
454 t6.t6_port = ((struct sockaddr_in6 *) addr)->sin6_port;
462 /* modify our published address list */
463 plugin->env->notify_address (plugin->env->cls,
470 * Function called for a quick conversion of the binary address to
471 * a numeric address. Note that the caller must not free the
472 * address and that the next call to this function is allowed
473 * to override the address again.
475 * @param cls closure ('struct Plugin*')
476 * @param addr binary address
477 * @param addrlen length of the address
478 * @return string representing the same address
481 tcp_address_to_string (void *cls,
485 static char rbuf[INET6_ADDRSTRLEN + 12];
486 char buf[INET6_ADDRSTRLEN];
490 const struct IPv4TcpAddress *t4;
491 const struct IPv6TcpAddress *t6;
495 if (addrlen == sizeof (struct IPv6TcpAddress))
499 port = ntohs (t6->t6_port);
500 memcpy (&a6, &t6->ipv6_addr, sizeof (a6));
503 else if (addrlen == sizeof (struct IPv4TcpAddress))
507 port = ntohs (t4->t4_port);
508 memcpy (&a4, &t4->ipv4_addr, sizeof (a4));
513 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
515 _("Unexpected address length: %u bytes\n"),
516 (unsigned int) addrlen);
520 if (NULL == inet_ntop (af, sb, buf, INET6_ADDRSTRLEN))
522 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
525 GNUNET_snprintf (rbuf,
527 (af == AF_INET6) ? "[%s]:%u" : "%s:%u",
535 * Find the session handle for the given client.
537 * @param plugin the plugin
538 * @param client which client to find the session handle for
539 * @return NULL if no matching session exists
541 static struct Session *
542 find_session_by_client (struct Plugin *plugin,
543 const struct GNUNET_SERVER_Client *client)
547 ret = plugin->sessions;
548 while ((ret != NULL) && (client != ret->client))
555 * Create a new session. Also queues a welcome message.
557 * @param plugin the plugin
558 * @param target peer to connect to
559 * @param client client to use
560 * @param is_nat this a NAT session, we should wait for a client to
561 * connect to us from an address, then assign that to
563 * @return new session object
565 static struct Session *
566 create_session (struct Plugin *plugin,
567 const struct GNUNET_PeerIdentity *target,
568 struct GNUNET_SERVER_Client *client,
572 struct PendingMessage *pm;
573 struct WelcomeMessage welcome;
575 if (is_nat != GNUNET_YES)
576 GNUNET_assert (client != NULL);
578 GNUNET_assert (client == NULL);
580 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
582 "Creating new session for peer `%4s'\n",
583 GNUNET_i2s (target));
585 ret = GNUNET_malloc (sizeof (struct Session));
586 ret->last_activity = GNUNET_TIME_absolute_get ();
587 ret->plugin = plugin;
588 ret->is_nat = is_nat;
589 if (is_nat != GNUNET_YES) /* If not a NAT WAIT conn, add it to global list */
591 ret->next = plugin->sessions;
592 plugin->sessions = ret;
594 ret->client = client;
595 ret->target = *target;
596 ret->expecting_welcome = GNUNET_YES;
597 pm = GNUNET_malloc (sizeof (struct PendingMessage) + sizeof (struct WelcomeMessage));
598 pm->msg = (const char*) &pm[1];
599 pm->message_size = sizeof (struct WelcomeMessage);
600 welcome.header.size = htons (sizeof (struct WelcomeMessage));
601 welcome.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME);
602 welcome.clientIdentity = *plugin->env->my_identity;
603 memcpy (&pm[1], &welcome, sizeof (welcome));
604 pm->timeout = GNUNET_TIME_UNIT_FOREVER_ABS;
605 GNUNET_STATISTICS_update (plugin->env->stats,
606 gettext_noop ("# bytes currently in TCP buffers"),
609 GNUNET_CONTAINER_DLL_insert (ret->pending_messages_head,
610 ret->pending_messages_tail,
612 if (is_nat != GNUNET_YES)
613 GNUNET_STATISTICS_update (plugin->env->stats,
614 gettext_noop ("# TCP sessions active"),
622 * If we have pending messages, ask the server to
623 * transmit them (schedule the respective tasks, etc.)
625 * @param session for which session should we do this
627 static void process_pending_messages (struct Session *session);
631 * Function called to notify a client about the socket
632 * being ready to queue more data. "buf" will be
633 * NULL and "size" zero if the socket was closed for
634 * writing in the meantime.
637 * @param size number of bytes available in buf
638 * @param buf where the callee should write the message
639 * @return number of bytes written to buf
642 do_transmit (void *cls, size_t size, void *buf)
644 struct Session *session = cls;
645 struct GNUNET_PeerIdentity pid;
646 struct Plugin *plugin;
647 struct PendingMessage *pos;
648 struct PendingMessage *hd;
649 struct PendingMessage *tl;
650 struct GNUNET_TIME_Absolute now;
654 GNUNET_assert (session != NULL);
655 session->transmit_handle = NULL;
656 plugin = session->plugin;
660 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
662 "Timeout trying to transmit to peer `%4s', discarding message queue.\n",
663 GNUNET_i2s (&session->target));
665 /* timeout; cancel all messages that have already expired */
669 now = GNUNET_TIME_absolute_get ();
670 while ( (NULL != (pos = session->pending_messages_head)) &&
671 (pos->timeout.abs_value <= now.abs_value) )
673 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
674 session->pending_messages_tail,
677 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
679 "Failed to transmit %u byte message to `%4s'.\n",
681 GNUNET_i2s (&session->target));
683 ret += pos->message_size;
684 GNUNET_CONTAINER_DLL_insert_after (hd, tl, tl, pos);
686 /* do this call before callbacks (so that if callbacks destroy
687 session, they have a chance to cancel actions done by this
689 process_pending_messages (session);
690 pid = session->target;
691 /* no do callbacks and do not use session again since
692 the callbacks may abort the session */
693 while (NULL != (pos = hd))
695 GNUNET_CONTAINER_DLL_remove (hd, tl, pos);
696 if (pos->transmit_cont != NULL)
697 pos->transmit_cont (pos->transmit_cont_cls,
698 &pid, GNUNET_SYSERR);
701 GNUNET_STATISTICS_update (plugin->env->stats,
702 gettext_noop ("# bytes currently in TCP buffers"),
705 GNUNET_STATISTICS_update (plugin->env->stats,
706 gettext_noop ("# bytes discarded by TCP (timeout)"),
711 /* copy all pending messages that would fit */
716 while (NULL != (pos = session->pending_messages_head))
718 if (ret + pos->message_size > size)
720 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
721 session->pending_messages_tail,
723 GNUNET_assert (size >= pos->message_size);
724 /* FIXME: this memcpy can be up to 7% of our total runtime */
725 memcpy (cbuf, pos->msg, pos->message_size);
726 cbuf += pos->message_size;
727 ret += pos->message_size;
728 size -= pos->message_size;
729 GNUNET_CONTAINER_DLL_insert_after (hd, tl, tl, pos);
731 /* schedule 'continuation' before callbacks so that callbacks that
732 cancel everything don't cause us to use a session that no longer
734 process_pending_messages (session);
735 session->last_activity = GNUNET_TIME_absolute_get ();
736 pid = session->target;
737 /* we'll now call callbacks that may cancel the session; hence
738 we should not use 'session' after this point */
739 while (NULL != (pos = hd))
741 GNUNET_CONTAINER_DLL_remove (hd, tl, pos);
742 if (pos->transmit_cont != NULL)
743 pos->transmit_cont (pos->transmit_cont_cls,
747 GNUNET_assert (hd == NULL);
748 GNUNET_assert (tl == NULL);
750 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
752 "Transmitting %u bytes\n",
755 GNUNET_STATISTICS_update (plugin->env->stats,
756 gettext_noop ("# bytes currently in TCP buffers"),
759 GNUNET_STATISTICS_update (plugin->env->stats,
760 gettext_noop ("# bytes transmitted via TCP"),
768 * If we have pending messages, ask the server to
769 * transmit them (schedule the respective tasks, etc.)
771 * @param session for which session should we do this
774 process_pending_messages (struct Session *session)
776 struct PendingMessage *pm;
778 GNUNET_assert (session->client != NULL);
779 if (session->transmit_handle != NULL)
781 if (NULL == (pm = session->pending_messages_head))
784 session->transmit_handle
785 = GNUNET_SERVER_notify_transmit_ready (session->client,
787 GNUNET_TIME_absolute_get_remaining
789 &do_transmit, session);
794 * Functions with this signature are called whenever we need
795 * to close a session due to a disconnect or failure to
796 * establish a connection.
798 * @param session session to close down
801 disconnect_session (struct Session *session)
803 struct Session *prev;
805 struct PendingMessage *pm;
808 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
810 "Disconnecting from `%4s' at %s.\n",
811 GNUNET_i2s (&session->target),
812 (session->connect_addr != NULL) ?
813 tcp_address_to_string (session->plugin,
814 session->connect_addr,
815 session->connect_alen) : "*");
817 /* remove from session list */
819 pos = session->plugin->sessions;
820 while (pos != session)
826 session->plugin->sessions = session->next;
828 prev->next = session->next;
831 if (session->transmit_handle != NULL)
833 GNUNET_CONNECTION_notify_transmit_ready_cancel
834 (session->transmit_handle);
835 session->transmit_handle = NULL;
837 session->plugin->env->session_end (session->plugin->env->cls,
840 while (NULL != (pm = session->pending_messages_head))
843 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
845 pm->transmit_cont != NULL
846 ? "Could not deliver message to `%4s'.\n"
847 : "Could not deliver message to `%4s', notifying.\n",
848 GNUNET_i2s (&session->target));
850 GNUNET_STATISTICS_update (session->plugin->env->stats,
851 gettext_noop ("# bytes currently in TCP buffers"),
852 - (int64_t) pm->message_size,
854 GNUNET_STATISTICS_update (session->plugin->env->stats,
855 gettext_noop ("# bytes discarded by TCP (disconnect)"),
858 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
859 session->pending_messages_tail,
861 if (NULL != pm->transmit_cont)
862 pm->transmit_cont (pm->transmit_cont_cls,
863 &session->target, GNUNET_SYSERR);
866 GNUNET_break (session->client != NULL);
867 if (session->receive_delay_task != GNUNET_SCHEDULER_NO_TASK)
869 GNUNET_SCHEDULER_cancel (session->receive_delay_task);
870 if (session->client != NULL)
871 GNUNET_SERVER_receive_done (session->client,
874 if (session->client != NULL)
876 GNUNET_SERVER_client_drop (session->client);
877 session->client = NULL;
879 GNUNET_STATISTICS_update (session->plugin->env->stats,
880 gettext_noop ("# TCP sessions active"),
883 GNUNET_free_non_null (session->connect_addr);
884 GNUNET_assert (NULL == session->transmit_handle);
885 GNUNET_free (session);
890 * Given two otherwise equivalent sessions, pick the better one.
892 * @param s1 one session (also default)
893 * @param s2 other session
894 * @return "better" session (more active)
896 static struct Session *
897 select_better_session (struct Session *s1,
904 if ( (s1->expecting_welcome == GNUNET_NO) &&
905 (s2->expecting_welcome == GNUNET_YES) )
907 if ( (s1->expecting_welcome == GNUNET_YES) &&
908 (s2->expecting_welcome == GNUNET_NO) )
910 if (s1->last_activity.abs_value < s2->last_activity.abs_value)
912 if (s1->last_activity.abs_value > s2->last_activity.abs_value)
914 if ( (GNUNET_YES == s1->inbound) &&
915 (GNUNET_NO == s2->inbound) )
917 if ( (GNUNET_NO == s1->inbound) &&
918 (GNUNET_YES == s2->inbound) )
926 * Function that can be used by the transport service to transmit
927 * a message using the plugin. Note that in the case of a
928 * peer disconnecting, the continuation MUST be called
929 * prior to the disconnect notification itself. This function
930 * will be called with this peer's HELLO message to initiate
931 * a fresh connection to another peer.
934 * @param target who should receive this message
935 * @param msg the message to transmit
936 * @param msgbuf_size number of bytes in 'msg'
937 * @param priority how important is the message (most plugins will
938 * ignore message priority and just FIFO)
939 * @param timeout how long to wait at most for the transmission (does not
940 * require plugins to discard the message after the timeout,
941 * just advisory for the desired delay; most plugins will ignore
943 * @param session which session must be used (or NULL for "any")
944 * @param addr the address to use (can be NULL if the plugin
945 * is "on its own" (i.e. re-use existing TCP connection))
946 * @param addrlen length of the address in bytes
947 * @param force_address GNUNET_YES if the plugin MUST use the given address,
948 * GNUNET_NO means the plugin may use any other address and
949 * GNUNET_SYSERR means that only reliable existing
950 * bi-directional connections should be used (regardless
952 * @param cont continuation to call once the message has
953 * been transmitted (or if the transport is ready
954 * for the next transmission call; or if the
955 * peer disconnected...); can be NULL
956 * @param cont_cls closure for cont
957 * @return number of bytes used (on the physical network, with overheads);
958 * -1 on hard errors (i.e. address invalid); 0 is a legal value
959 * and does NOT mean that the message was not transmitted (DV and NAT)
962 tcp_plugin_send (void *cls,
963 const struct GNUNET_PeerIdentity *target,
967 struct GNUNET_TIME_Relative timeout,
968 struct Session *session,
972 GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
974 struct Plugin *plugin = cls;
975 struct Session *cand_session;
976 struct Session *next;
977 struct PendingMessage *pm;
978 struct GNUNET_CONNECTION_Handle *sa;
982 struct sockaddr_in a4;
983 struct sockaddr_in6 a6;
984 const struct IPv4TcpAddress *t4;
985 const struct IPv6TcpAddress *t6;
986 unsigned int is_natd;
988 GNUNET_STATISTICS_update (plugin->env->stats,
989 gettext_noop ("# bytes TCP was asked to transmit"),
992 /* FIXME: we could do this cheaper with a hash table
993 where we could restrict the iteration to entries that match
994 the target peer... */
999 next = plugin->sessions;
1000 while (NULL != (session = next))
1002 next = session->next;
1003 GNUNET_assert (session->client != NULL);
1004 if (0 != memcmp (target,
1006 sizeof (struct GNUNET_PeerIdentity)))
1008 if ( ( (GNUNET_SYSERR == force_address) &&
1009 (session->expecting_welcome == GNUNET_NO) ) ||
1010 (GNUNET_NO == force_address) )
1012 cand_session = select_better_session (cand_session,
1016 if (GNUNET_SYSERR == force_address)
1018 GNUNET_break (GNUNET_YES == force_address);
1024 if ( (addrlen != session->connect_alen) &&
1025 (session->is_nat == GNUNET_NO) )
1027 if ((0 != memcmp (session->connect_addr,
1029 addrlen)) && (session->is_nat == GNUNET_NO))
1031 cand_session = select_better_session (cand_session,
1034 session = cand_session;
1036 if ( (session == NULL) &&
1040 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1042 "Asked to transmit to `%4s' without address and I have no existing connection (failing).\n",
1043 GNUNET_i2s (target));
1045 GNUNET_STATISTICS_update (plugin->env->stats,
1046 gettext_noop ("# bytes discarded by TCP (no address and no connection)"),
1051 if (session == NULL)
1053 if (addrlen == sizeof (struct IPv6TcpAddress))
1057 memset (&a6, 0, sizeof (a6));
1058 #if HAVE_SOCKADDR_IN_SIN_LEN
1059 a6.sin6_len = sizeof (a6);
1061 a6.sin6_family = AF_INET6;
1062 a6.sin6_port = t6->t6_port;
1063 if (t6->t6_port == 0)
1064 is_natd = GNUNET_YES;
1065 memcpy (&a6.sin6_addr,
1067 sizeof (struct in6_addr));
1071 else if (addrlen == sizeof (struct IPv4TcpAddress))
1075 memset (&a4, 0, sizeof (a4));
1076 #if HAVE_SOCKADDR_IN_SIN_LEN
1077 a4.sin_len = sizeof (a4);
1079 a4.sin_family = AF_INET;
1080 a4.sin_port = t4->t4_port;
1081 if (t4->t4_port == 0)
1082 is_natd = GNUNET_YES;
1083 a4.sin_addr.s_addr = t4->ipv4_addr;
1089 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
1091 _("Address of unexpected length: %u\n"),
1097 if ((is_natd == GNUNET_YES) && (addrlen == sizeof (struct IPv6TcpAddress)))
1098 return -1; /* NAT client only works with IPv4 addresses */
1099 if (0 == plugin->max_connections)
1100 return -1; /* saturated */
1102 if ( (is_natd == GNUNET_YES) &&
1103 (NULL != plugin->nat) &&
1104 (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns,
1105 &target->hashPubKey)) )
1108 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1110 _("Found valid IPv4 NAT address (creating session)!\n"));
1112 session = create_session (plugin,
1116 GNUNET_assert (session != NULL);
1118 /* create new message entry */
1119 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msgbuf_size);
1120 /* FIXME: the memset of this malloc can be up to 2% of our total runtime */
1121 pm->msg = (const char*) &pm[1];
1122 memcpy (&pm[1], msg, msgbuf_size);
1123 /* FIXME: this memcpy can be up to 7% of our total run-time
1124 (for transport service) */
1125 pm->message_size = msgbuf_size;
1126 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1127 pm->transmit_cont = cont;
1128 pm->transmit_cont_cls = cont_cls;
1130 /* append pm to pending_messages list */
1131 GNUNET_CONTAINER_DLL_insert_after (session->pending_messages_head,
1132 session->pending_messages_tail,
1133 session->pending_messages_tail,
1136 GNUNET_assert(GNUNET_CONTAINER_multihashmap_put(plugin->nat_wait_conns,
1137 &target->hashPubKey,
1139 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY) == GNUNET_OK);
1141 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1143 "Created NAT WAIT connection to `%4s' at `%s'\n",
1144 GNUNET_i2s (target),
1145 GNUNET_a2s (sb, sbs));
1147 GNUNET_NAT_run_client (plugin->nat, &a4);
1150 if ( (is_natd == GNUNET_YES) &&
1151 (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns,
1152 &target->hashPubKey)) )
1154 /* Only do one NAT punch attempt per peer identity */
1157 sa = GNUNET_CONNECTION_create_from_sockaddr (af, sb, sbs);
1161 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1163 "Failed to create connection to `%4s' at `%s'\n",
1164 GNUNET_i2s (target),
1165 GNUNET_a2s (sb, sbs));
1167 GNUNET_STATISTICS_update (plugin->env->stats,
1168 gettext_noop ("# bytes discarded by TCP (failed to connect)"),
1173 GNUNET_assert (0 != plugin->max_connections);
1174 plugin->max_connections--;
1176 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1178 "Asked to transmit to `%4s', creating fresh session using address `%s'.\n",
1179 GNUNET_i2s (target),
1180 GNUNET_a2s (sb, sbs));
1182 session = create_session (plugin,
1184 GNUNET_SERVER_connect_socket (plugin->server,
1187 session->connect_addr = GNUNET_malloc (addrlen);
1188 memcpy (session->connect_addr,
1191 session->connect_alen = addrlen;
1193 else /* session != NULL */
1195 /* check if session is valid */
1196 struct Session * ses = plugin->sessions;
1197 while ((ses != NULL) && (ses != session))
1205 GNUNET_assert (session != NULL);
1206 GNUNET_assert (session->client != NULL);
1209 GNUNET_SERVER_client_set_timeout(session->client, GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
1210 GNUNET_STATISTICS_update (plugin->env->stats,
1211 gettext_noop ("# bytes currently in TCP buffers"),
1214 /* create new message entry */
1215 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msgbuf_size);
1216 pm->msg = (const char*) &pm[1];
1217 memcpy (&pm[1], msg, msgbuf_size);
1218 pm->message_size = msgbuf_size;
1219 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1220 pm->transmit_cont = cont;
1221 pm->transmit_cont_cls = cont_cls;
1223 /* append pm to pending_messages list */
1224 GNUNET_CONTAINER_DLL_insert_after (session->pending_messages_head,
1225 session->pending_messages_tail,
1226 session->pending_messages_tail,
1229 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1231 "Asked to transmit %u bytes to `%s', added message to list.\n",
1233 GNUNET_i2s (target));
1235 process_pending_messages (session);
1241 * Function that can be called to force a disconnect from the
1242 * specified neighbour. This should also cancel all previously
1243 * scheduled transmissions. Obviously the transmission may have been
1244 * partially completed already, which is OK. The plugin is supposed
1245 * to close the connection (if applicable) and no longer call the
1246 * transmit continuation(s).
1248 * Finally, plugin MUST NOT call the services's receive function to
1249 * notify the service that the connection to the specified target was
1250 * closed after a getting this call.
1252 * @param cls closure
1253 * @param target peer for which the last transmission is
1257 tcp_plugin_disconnect (void *cls,
1258 const struct GNUNET_PeerIdentity *target)
1260 struct Plugin *plugin = cls;
1261 struct Session *session;
1262 struct Session *next;
1263 struct PendingMessage *pm;
1266 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1268 "Asked to cancel session with `%4s'\n",
1269 GNUNET_i2s (target));
1271 next = plugin->sessions;
1272 while (NULL != (session = next))
1274 next = session->next;
1275 if (0 != memcmp (target,
1277 sizeof (struct GNUNET_PeerIdentity)))
1279 pm = session->pending_messages_head;
1282 pm->transmit_cont = NULL;
1283 pm->transmit_cont_cls = NULL;
1286 GNUNET_STATISTICS_update (session->plugin->env->stats,
1287 gettext_noop ("# transport-service disconnect requests for TCP"),
1290 disconnect_session (session);
1296 * Context for address to string conversion.
1298 struct PrettyPrinterContext
1301 * Function to call with the result.
1303 GNUNET_TRANSPORT_AddressStringCallback asc;
1306 * Clsoure for 'asc'.
1311 * Port to add after the IP address.
1318 * Append our port and forward the result.
1320 * @param cls the 'struct PrettyPrinterContext*'
1321 * @param hostname hostname part of the address
1324 append_port (void *cls, const char *hostname)
1326 struct PrettyPrinterContext *ppc = cls;
1329 if (hostname == NULL)
1331 ppc->asc (ppc->asc_cls, NULL);
1335 GNUNET_asprintf (&ret, "%s:%d", hostname, ppc->port);
1336 ppc->asc (ppc->asc_cls, ret);
1342 * Convert the transports address to a nice, human-readable
1345 * @param cls closure
1346 * @param type name of the transport that generated the address
1347 * @param addr one of the addresses of the host, NULL for the last address
1348 * the specific address format depends on the transport
1349 * @param addrlen length of the address
1350 * @param numeric should (IP) addresses be displayed in numeric form?
1351 * @param timeout after how long should we give up?
1352 * @param asc function to call on each string
1353 * @param asc_cls closure for asc
1356 tcp_plugin_address_pretty_printer (void *cls,
1361 struct GNUNET_TIME_Relative timeout,
1362 GNUNET_TRANSPORT_AddressStringCallback asc,
1365 struct PrettyPrinterContext *ppc;
1368 struct sockaddr_in a4;
1369 struct sockaddr_in6 a6;
1370 const struct IPv4TcpAddress *t4;
1371 const struct IPv6TcpAddress *t6;
1374 if (addrlen == sizeof (struct IPv6TcpAddress))
1377 memset (&a6, 0, sizeof (a6));
1378 a6.sin6_family = AF_INET6;
1379 a6.sin6_port = t6->t6_port;
1380 memcpy (&a6.sin6_addr,
1382 sizeof (struct in6_addr));
1383 port = ntohs (t6->t6_port);
1387 else if (addrlen == sizeof (struct IPv4TcpAddress))
1390 memset (&a4, 0, sizeof (a4));
1391 a4.sin_family = AF_INET;
1392 a4.sin_port = t4->t4_port;
1393 a4.sin_addr.s_addr = t4->ipv4_addr;
1394 port = ntohs (t4->t4_port);
1400 /* invalid address */
1401 GNUNET_break_op (0);
1402 asc (asc_cls, NULL);
1405 ppc = GNUNET_malloc (sizeof (struct PrettyPrinterContext));
1407 ppc->asc_cls = asc_cls;
1409 GNUNET_RESOLVER_hostname_get (sb,
1411 !numeric, timeout, &append_port, ppc);
1416 * Check if the given port is plausible (must be either our listen
1417 * port or our advertised port), or any port if we are behind NAT
1418 * and do not have a port open. If it is neither, we return
1421 * @param plugin global variables
1422 * @param in_port port number to check
1423 * @return GNUNET_OK if port is either open_port or adv_port
1426 check_port (struct Plugin *plugin,
1429 if ((in_port == plugin->adv_port) || (in_port == plugin->open_port))
1431 return GNUNET_SYSERR;
1436 * Function that will be called to check if a binary address for this
1437 * plugin is well-formed and corresponds to an address for THIS peer
1438 * (as per our configuration). Naturally, if absolutely necessary,
1439 * plugins can be a bit conservative in their answer, but in general
1440 * plugins should make sure that the address does not redirect
1441 * traffic to a 3rd party that might try to man-in-the-middle our
1444 * @param cls closure, our 'struct Plugin*'
1445 * @param addr pointer to the address
1446 * @param addrlen length of addr
1447 * @return GNUNET_OK if this is a plausible address for this peer
1448 * and transport, GNUNET_SYSERR if not
1451 tcp_plugin_check_address (void *cls,
1455 struct Plugin *plugin = cls;
1456 struct IPv4TcpAddress *v4;
1457 struct IPv6TcpAddress *v6;
1459 if ((addrlen != sizeof (struct IPv4TcpAddress)) &&
1460 (addrlen != sizeof (struct IPv6TcpAddress)))
1462 GNUNET_break_op (0);
1463 return GNUNET_SYSERR;
1465 if (addrlen == sizeof (struct IPv4TcpAddress))
1467 v4 = (struct IPv4TcpAddress *) addr;
1469 check_port (plugin, ntohs (v4->t4_port)))
1470 return GNUNET_SYSERR;
1472 GNUNET_NAT_test_address (plugin->nat,
1473 &v4->ipv4_addr, sizeof (struct in_addr)))
1474 return GNUNET_SYSERR;
1478 v6 = (struct IPv6TcpAddress *) addr;
1479 if (IN6_IS_ADDR_LINKLOCAL (&v6->ipv6_addr))
1481 GNUNET_break_op (0);
1482 return GNUNET_SYSERR;
1485 check_port (plugin, ntohs (v6->t6_port)))
1486 return GNUNET_SYSERR;
1488 GNUNET_NAT_test_address (plugin->nat,
1489 &v6->ipv6_addr, sizeof (struct in6_addr)))
1490 return GNUNET_SYSERR;
1497 * We've received a nat probe from this peer via TCP. Finish
1498 * creating the client session and resume sending of queued
1501 * @param cls closure
1502 * @param client identification of the client
1503 * @param message the actual message
1506 handle_tcp_nat_probe (void *cls,
1507 struct GNUNET_SERVER_Client *client,
1508 const struct GNUNET_MessageHeader *message)
1510 struct Plugin *plugin = cls;
1511 struct Session *session;
1512 const struct TCP_NAT_ProbeMessage *tcp_nat_probe;
1515 struct IPv4TcpAddress *t4;
1516 struct IPv6TcpAddress *t6;
1517 const struct sockaddr_in *s4;
1518 const struct sockaddr_in6 *s6;
1521 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1523 "received NAT probe\n");
1525 /* We have received a TCP NAT probe, meaning we (hopefully) initiated
1526 * a connection to this peer by running gnunet-nat-client. This peer
1527 * received the punch message and now wants us to use the new connection
1528 * as the default for that peer. Do so and then send a WELCOME message
1529 * so we can really be connected!
1531 if (ntohs(message->size) != sizeof(struct TCP_NAT_ProbeMessage))
1534 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1538 tcp_nat_probe = (const struct TCP_NAT_ProbeMessage *)message;
1539 if (0 == memcmp (&tcp_nat_probe->clientIdentity,
1540 plugin->env->my_identity,
1541 sizeof (struct GNUNET_PeerIdentity)))
1543 /* refuse connections from ourselves */
1544 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1548 session = GNUNET_CONTAINER_multihashmap_get(plugin->nat_wait_conns,
1549 &tcp_nat_probe->clientIdentity.hashPubKey);
1550 if (session == NULL)
1553 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1555 "Did NOT find session for NAT probe!\n");
1557 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1561 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1563 "Found session for NAT probe!\n");
1565 GNUNET_assert(GNUNET_CONTAINER_multihashmap_remove(plugin->nat_wait_conns,
1566 &tcp_nat_probe->clientIdentity.hashPubKey,
1567 session) == GNUNET_YES);
1569 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1572 GNUNET_free (session);
1573 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1577 GNUNET_SERVER_client_keep (client);
1578 session->client = client;
1579 session->last_activity = GNUNET_TIME_absolute_get ();
1580 session->inbound = GNUNET_NO;
1583 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1585 "Found address `%s' for incoming connection\n",
1586 GNUNET_a2s (vaddr, alen));
1588 switch (((const struct sockaddr *)vaddr)->sa_family)
1592 t4 = GNUNET_malloc (sizeof (struct IPv4TcpAddress));
1593 t4->t4_port = s4->sin_port;
1594 t4->ipv4_addr = s4->sin_addr.s_addr;
1595 session->connect_addr = t4;
1596 session->connect_alen = sizeof (struct IPv4TcpAddress);
1600 t6 = GNUNET_malloc (sizeof (struct IPv6TcpAddress));
1601 t6->t6_port = s6->sin6_port;
1602 memcpy (&t6->ipv6_addr,
1604 sizeof (struct in6_addr));
1605 session->connect_addr = t6;
1606 session->connect_alen = sizeof (struct IPv6TcpAddress);
1609 GNUNET_break_op (0);
1611 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1613 "Bad address for incoming connection!\n");
1615 GNUNET_free (vaddr);
1616 GNUNET_SERVER_client_drop (client);
1617 GNUNET_free (session);
1618 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1621 GNUNET_free (vaddr);
1623 session->next = plugin->sessions;
1624 plugin->sessions = session;
1625 GNUNET_STATISTICS_update (plugin->env->stats,
1626 gettext_noop ("# TCP sessions active"),
1629 process_pending_messages (session);
1630 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1635 * We've received a welcome from this peer via TCP. Possibly create a
1636 * fresh client record and send back our welcome.
1638 * @param cls closure
1639 * @param client identification of the client
1640 * @param message the actual message
1643 handle_tcp_welcome (void *cls,
1644 struct GNUNET_SERVER_Client *client,
1645 const struct GNUNET_MessageHeader *message)
1647 struct Plugin *plugin = cls;
1648 const struct WelcomeMessage *wm = (const struct WelcomeMessage *) message;
1649 struct Session *session;
1652 struct IPv4TcpAddress *t4;
1653 struct IPv6TcpAddress *t6;
1654 const struct sockaddr_in *s4;
1655 const struct sockaddr_in6 *s6;
1657 if (0 == memcmp (&wm->clientIdentity,
1658 plugin->env->my_identity,
1659 sizeof (struct GNUNET_PeerIdentity)))
1661 /* refuse connections from ourselves */
1662 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1666 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1668 "Received %s message from `%4s'.\n",
1670 GNUNET_i2s (&wm->clientIdentity));
1672 GNUNET_STATISTICS_update (plugin->env->stats,
1673 gettext_noop ("# TCP WELCOME messages received"),
1676 session = find_session_by_client (plugin, client);
1678 if (session == NULL)
1681 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1683 "Received %s message from a `%4s', creating new session\n",
1685 GNUNET_i2s (&wm->clientIdentity));
1687 GNUNET_SERVER_client_keep (client);
1688 session = create_session (plugin,
1689 &wm->clientIdentity,
1692 session->inbound = GNUNET_YES;
1694 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1697 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1699 "Found address `%s' for incoming connection\n",
1700 GNUNET_a2s (vaddr, alen));
1702 if (alen == sizeof (struct sockaddr_in))
1705 t4 = GNUNET_malloc (sizeof (struct IPv4TcpAddress));
1706 t4->t4_port = s4->sin_port;
1707 t4->ipv4_addr = s4->sin_addr.s_addr;
1708 session->connect_addr = t4;
1709 session->connect_alen = sizeof (struct IPv4TcpAddress);
1711 else if (alen == sizeof (struct sockaddr_in6))
1714 t6 = GNUNET_malloc (sizeof (struct IPv6TcpAddress));
1715 t6->t6_port = s6->sin6_port;
1716 memcpy (&t6->ipv6_addr,
1718 sizeof (struct in6_addr));
1719 session->connect_addr = t6;
1720 session->connect_alen = sizeof (struct IPv6TcpAddress);
1723 GNUNET_free (vaddr);
1728 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1730 "Did not obtain TCP socket address for incoming connection\n");
1733 process_pending_messages (session);
1739 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1741 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1743 "Found address `%s' (already have session)\n",
1744 GNUNET_a2s (vaddr, alen));
1745 GNUNET_free (vaddr);
1750 if (session->expecting_welcome != GNUNET_YES)
1752 GNUNET_break_op (0);
1753 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1756 session->last_activity = GNUNET_TIME_absolute_get ();
1757 session->expecting_welcome = GNUNET_NO;
1758 GNUNET_SERVER_client_set_timeout(client, GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
1759 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1764 * Task to signal the server that we can continue
1765 * receiving from the TCP client now.
1767 * @param cls the 'struct Session*'
1768 * @param tc task context (unused)
1771 delayed_done (void *cls,
1772 const struct GNUNET_SCHEDULER_TaskContext *tc)
1774 struct Session *session = cls;
1775 struct GNUNET_TIME_Relative delay;
1777 session->receive_delay_task = GNUNET_SCHEDULER_NO_TASK;
1778 delay = session->plugin->env->receive (session->plugin->env->cls,
1784 if (delay.rel_value == 0)
1785 GNUNET_SERVER_receive_done (session->client, GNUNET_OK);
1787 session->receive_delay_task =
1788 GNUNET_SCHEDULER_add_delayed (delay, &delayed_done, session);
1793 * We've received data for this peer via TCP. Unbox,
1794 * compute latency and forward.
1796 * @param cls closure
1797 * @param client identification of the client
1798 * @param message the actual message
1801 handle_tcp_data (void *cls,
1802 struct GNUNET_SERVER_Client *client,
1803 const struct GNUNET_MessageHeader *message)
1805 struct Plugin *plugin = cls;
1806 struct Session *session;
1807 struct GNUNET_TIME_Relative delay;
1810 type = ntohs (message->type);
1811 if ( (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME == type) ||
1812 (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE == type) )
1814 /* We don't want to propagate WELCOME and NAT Probe messages up! */
1815 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1818 session = find_session_by_client (plugin, client);
1819 if ( (NULL == session) || (GNUNET_YES == session->expecting_welcome) )
1821 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1824 session->last_activity = GNUNET_TIME_absolute_get ();
1826 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1828 "Passing %u bytes of type %u from `%4s' to transport service.\n",
1829 (unsigned int) ntohs (message->size),
1830 (unsigned int) ntohs (message->type),
1831 GNUNET_i2s (&session->target));
1833 GNUNET_STATISTICS_update (plugin->env->stats,
1834 gettext_noop ("# bytes received via TCP"),
1835 ntohs (message->size),
1837 struct GNUNET_TRANSPORT_ATS_Information distance[2];
1838 distance[0].type = htonl (GNUNET_TRANSPORT_ATS_QUALITY_NET_DISTANCE);
1839 distance[0].value = htonl (1);
1840 distance[1].type = htonl (GNUNET_TRANSPORT_ATS_ARRAY_TERMINATOR);
1841 distance[1].value = htonl (0);
1842 delay = plugin->env->receive (plugin->env->cls, &session->target, message,
1843 (const struct GNUNET_TRANSPORT_ATS_Information *) &distance,
1846 (GNUNET_YES == session->inbound) ? NULL : session->connect_addr,
1847 (GNUNET_YES == session->inbound) ? 0 : session->connect_alen);
1848 if (delay.rel_value == 0)
1850 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1855 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1857 "Throttling receiving from `%s' for %llu ms\n",
1858 GNUNET_i2s (&session->target),
1859 (unsigned long long) delay.rel_value);
1861 GNUNET_SERVER_disable_receive_done_warning (client);
1862 session->receive_delay_task =
1863 GNUNET_SCHEDULER_add_delayed (delay, &delayed_done, session);
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,
1877 struct GNUNET_SERVER_Client *client)
1879 struct Plugin *plugin = cls;
1880 struct Session *session;
1884 plugin->max_connections++;
1885 session = find_session_by_client (plugin, client);
1886 if (session == NULL)
1887 return; /* unknown, nothing to do */
1889 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1891 "Destroying session of `%4s' with %s due to network-level disconnect.\n",
1892 GNUNET_i2s (&session->target),
1893 (session->connect_addr != NULL) ?
1894 tcp_address_to_string (session->plugin,
1895 session->connect_addr,
1896 session->connect_alen) : "*");
1898 GNUNET_STATISTICS_update (session->plugin->env->stats,
1899 gettext_noop ("# network-level TCP disconnect events"),
1902 disconnect_session (session);
1907 * We can now send a probe message, copy into buffer to really send.
1909 * @param cls closure, a struct TCPProbeContext
1910 * @param size max size to copy
1911 * @param buf buffer to copy message to
1912 * @return number of bytes copied into buf
1915 notify_send_probe (void *cls,
1919 struct TCPProbeContext *tcp_probe_ctx = cls;
1920 struct Plugin *plugin = tcp_probe_ctx->plugin;
1923 tcp_probe_ctx->transmit_handle = NULL;
1924 GNUNET_CONTAINER_DLL_remove (plugin->probe_head,
1929 GNUNET_CONNECTION_destroy (tcp_probe_ctx->sock, GNUNET_NO);
1930 GNUNET_free(tcp_probe_ctx);
1933 GNUNET_assert(size >= sizeof(tcp_probe_ctx->message));
1934 memcpy(buf, &tcp_probe_ctx->message, sizeof(tcp_probe_ctx->message));
1935 GNUNET_SERVER_connect_socket (tcp_probe_ctx->plugin->server,
1936 tcp_probe_ctx->sock);
1937 ret = sizeof(tcp_probe_ctx->message);
1938 GNUNET_free(tcp_probe_ctx);
1944 * Function called by the NAT subsystem suggesting another peer wants
1945 * to connect to us via connection reversal. Try to connect back to the
1948 * @param cls closure
1949 * @param addr address to try
1950 * @param addrlen number of bytes in addr
1953 try_connection_reversal (void *cls,
1954 const struct sockaddr *addr,
1957 struct Plugin *plugin = cls;
1958 struct GNUNET_CONNECTION_Handle *sock;
1959 struct TCPProbeContext *tcp_probe_ctx;
1962 * We have received an ICMP response, ostensibly from a peer
1963 * that wants to connect to us! Send a message to establish a connection.
1965 sock = GNUNET_CONNECTION_create_from_sockaddr (AF_INET,
1970 /* failed for some odd reason (out of sockets?); ignore attempt */
1974 /* FIXME: do we need to track these probe context objects so that
1975 we can clean them up on plugin unload? */
1977 = GNUNET_malloc(sizeof(struct TCPProbeContext));
1978 tcp_probe_ctx->message.header.size
1979 = htons(sizeof(struct TCP_NAT_ProbeMessage));
1980 tcp_probe_ctx->message.header.type
1981 = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE);
1982 memcpy (&tcp_probe_ctx->message.clientIdentity,
1983 plugin->env->my_identity,
1984 sizeof(struct GNUNET_PeerIdentity));
1985 tcp_probe_ctx->plugin = plugin;
1986 tcp_probe_ctx->sock = sock;
1987 GNUNET_CONTAINER_DLL_insert (plugin->probe_head,
1990 tcp_probe_ctx->transmit_handle
1991 = GNUNET_CONNECTION_notify_transmit_ready (sock,
1992 ntohs (tcp_probe_ctx->message.header.size),
1993 GNUNET_TIME_UNIT_FOREVER_REL,
1994 ¬ify_send_probe, tcp_probe_ctx);
2000 * Entry point for the plugin.
2002 * @param cls closure, the 'struct GNUNET_TRANSPORT_PluginEnvironment*'
2003 * @return the 'struct GNUNET_TRANSPORT_PluginFunctions*' or NULL on error
2006 libgnunet_plugin_transport_tcp_init (void *cls)
2008 static const struct GNUNET_SERVER_MessageHandler my_handlers[] = {
2009 {&handle_tcp_welcome, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME,
2010 sizeof (struct WelcomeMessage)},
2011 {&handle_tcp_nat_probe, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE, sizeof (struct TCP_NAT_ProbeMessage)},
2012 {&handle_tcp_data, NULL, GNUNET_MESSAGE_TYPE_ALL, 0},
2015 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
2016 struct GNUNET_TRANSPORT_PluginFunctions *api;
2017 struct Plugin *plugin;
2018 struct GNUNET_SERVICE_Context *service;
2019 unsigned long long aport;
2020 unsigned long long bport;
2021 unsigned long long max_connections;
2023 struct GNUNET_TIME_Relative idle_timeout;
2025 struct sockaddr **addrs;
2026 socklen_t *addrlens;
2029 GNUNET_CONFIGURATION_get_value_number (env->cfg,
2033 max_connections = 128;
2037 GNUNET_CONFIGURATION_get_value_number (env->cfg,
2043 GNUNET_CONFIGURATION_get_value_number (env->cfg,
2049 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2051 _("Require valid port number for service `%s' in configuration!\n"),
2061 service = GNUNET_SERVICE_start ("transport-tcp", env->cfg);
2062 if (service == NULL)
2064 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING,
2066 _("Failed to start service.\n"));
2075 plugin = GNUNET_malloc (sizeof (struct Plugin));
2076 plugin->max_connections = max_connections;
2077 plugin->open_port = bport;
2078 plugin->adv_port = aport;
2080 plugin->lsock = NULL;
2081 if ( (service != NULL) &&
2083 (ret = GNUNET_SERVICE_get_server_addresses ("transport-tcp",
2088 plugin->nat = GNUNET_NAT_register (env->cfg,
2092 (const struct sockaddr **) addrs,
2094 &tcp_nat_port_map_callback,
2095 &try_connection_reversal,
2100 GNUNET_assert (addrs[ret] != NULL);
2101 GNUNET_free (addrs[ret]);
2103 GNUNET_free_non_null (addrs);
2104 GNUNET_free_non_null (addrlens);
2108 plugin->nat = GNUNET_NAT_register (env->cfg,
2113 &try_connection_reversal,
2116 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
2118 api->send = &tcp_plugin_send;
2119 api->disconnect = &tcp_plugin_disconnect;
2120 api->address_pretty_printer = &tcp_plugin_address_pretty_printer;
2121 api->check_address = &tcp_plugin_check_address;
2122 api->address_to_string = &tcp_address_to_string;
2123 plugin->service = service;
2124 if (service != NULL)
2126 plugin->server = GNUNET_SERVICE_get_server (service);
2131 GNUNET_CONFIGURATION_get_value_time (env->cfg,
2136 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2138 _("Failed to find option %s in section %s!\n"),
2141 if (plugin->nat != NULL)
2142 GNUNET_NAT_unregister (plugin->nat);
2143 GNUNET_free (plugin);
2147 plugin->server = GNUNET_SERVER_create_with_sockets (&plugin_tcp_access_check, plugin, NULL,
2148 idle_timeout, GNUNET_YES);
2150 plugin->handlers = GNUNET_malloc (sizeof (my_handlers));
2151 memcpy (plugin->handlers, my_handlers, sizeof (my_handlers));
2153 i < sizeof (my_handlers) / sizeof (struct GNUNET_SERVER_MessageHandler);
2155 plugin->handlers[i].callback_cls = plugin;
2156 GNUNET_SERVER_add_handlers (plugin->server, plugin->handlers);
2157 GNUNET_SERVER_disconnect_notify (plugin->server,
2160 plugin->nat_wait_conns = GNUNET_CONTAINER_multihashmap_create(16);
2162 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2164 _("TCP transport listening on port %llu\n"),
2167 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2169 _("TCP transport not listening on any port (client only)\n"));
2171 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2173 _("TCP transport advertises itself as being on port %llu\n"),
2180 * Exit point from the plugin.
2183 libgnunet_plugin_transport_tcp_done (void *cls)
2185 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
2186 struct Plugin *plugin = api->cls;
2187 struct Session *session;
2188 struct TCPProbeContext *tcp_probe;
2190 while (NULL != (session = plugin->sessions))
2191 disconnect_session (session);
2192 if (plugin->service != NULL)
2193 GNUNET_SERVICE_stop (plugin->service);
2195 GNUNET_SERVER_destroy (plugin->server);
2196 GNUNET_free (plugin->handlers);
2197 if (plugin->nat != NULL)
2198 GNUNET_NAT_unregister (plugin->nat);
2199 while (NULL != (tcp_probe = plugin->probe_head))
2201 GNUNET_CONTAINER_DLL_remove (plugin->probe_head,
2204 GNUNET_CONNECTION_destroy (tcp_probe->sock, GNUNET_NO);
2205 GNUNET_free (tcp_probe);
2207 GNUNET_CONTAINER_multihashmap_destroy (plugin->nat_wait_conns);
2208 GNUNET_free (plugin);
2213 /* end of plugin_transport_tcp.c */