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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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_connection_lib.h"
28 #include "gnunet_container_lib.h"
29 #include "gnunet_nat_lib.h"
30 #include "gnunet_os_lib.h"
31 #include "gnunet_protocols.h"
32 #include "gnunet_resolver_service.h"
33 #include "gnunet_server_lib.h"
34 #include "gnunet_service_lib.h"
35 #include "gnunet_signatures.h"
36 #include "gnunet_statistics_service.h"
37 #include "gnunet_transport_service.h"
38 #include "gnunet_transport_plugin.h"
39 #include "transport.h"
41 #define DEBUG_TCP GNUNET_NO
43 #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 session->transmit_handle = NULL;
655 plugin = session->plugin;
659 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
661 "Timeout trying to transmit to peer `%4s', discarding message queue.\n",
662 GNUNET_i2s (&session->target));
664 /* timeout; cancel all messages that have already expired */
668 now = GNUNET_TIME_absolute_get ();
669 while ( (NULL != (pos = session->pending_messages_head)) &&
670 (pos->timeout.abs_value <= now.abs_value) )
672 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
673 session->pending_messages_tail,
676 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
678 "Failed to transmit %u byte message to `%4s'.\n",
680 GNUNET_i2s (&session->target));
682 ret += pos->message_size;
683 GNUNET_CONTAINER_DLL_insert_after (hd, tl, tl, pos);
685 /* do this call before callbacks (so that if callbacks destroy
686 session, they have a chance to cancel actions done by this
688 process_pending_messages (session);
689 pid = session->target;
690 /* no do callbacks and do not use session again since
691 the callbacks may abort the session */
692 while (NULL != (pos = hd))
694 GNUNET_CONTAINER_DLL_remove (hd, tl, pos);
695 if (pos->transmit_cont != NULL)
696 pos->transmit_cont (pos->transmit_cont_cls,
697 &pid, GNUNET_SYSERR);
700 GNUNET_STATISTICS_update (plugin->env->stats,
701 gettext_noop ("# bytes currently in TCP buffers"),
704 GNUNET_STATISTICS_update (plugin->env->stats,
705 gettext_noop ("# bytes discarded by TCP (timeout)"),
710 /* copy all pending messages that would fit */
715 while (NULL != (pos = session->pending_messages_head))
717 if (ret + pos->message_size > size)
719 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
720 session->pending_messages_tail,
722 GNUNET_assert (size >= pos->message_size);
723 /* FIXME: this memcpy can be up to 7% of our total runtime */
724 memcpy (cbuf, pos->msg, pos->message_size);
725 cbuf += pos->message_size;
726 ret += pos->message_size;
727 size -= pos->message_size;
728 GNUNET_CONTAINER_DLL_insert_after (hd, tl, tl, pos);
730 /* schedule 'continuation' before callbacks so that callbacks that
731 cancel everything don't cause us to use a session that no longer
733 process_pending_messages (session);
734 session->last_activity = GNUNET_TIME_absolute_get ();
735 pid = session->target;
736 /* we'll now call callbacks that may cancel the session; hence
737 we should not use 'session' after this point */
738 while (NULL != (pos = hd))
740 GNUNET_CONTAINER_DLL_remove (hd, tl, pos);
741 if (pos->transmit_cont != NULL)
742 pos->transmit_cont (pos->transmit_cont_cls,
746 GNUNET_assert (hd == NULL);
747 GNUNET_assert (tl == NULL);
749 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
751 "Transmitting %u bytes\n",
754 GNUNET_STATISTICS_update (plugin->env->stats,
755 gettext_noop ("# bytes currently in TCP buffers"),
758 GNUNET_STATISTICS_update (plugin->env->stats,
759 gettext_noop ("# bytes transmitted via TCP"),
767 * If we have pending messages, ask the server to
768 * transmit them (schedule the respective tasks, etc.)
770 * @param session for which session should we do this
773 process_pending_messages (struct Session *session)
775 struct PendingMessage *pm;
777 GNUNET_assert (session->client != NULL);
778 if (session->transmit_handle != NULL)
780 if (NULL == (pm = session->pending_messages_head))
783 session->transmit_handle
784 = GNUNET_SERVER_notify_transmit_ready (session->client,
786 GNUNET_TIME_absolute_get_remaining
788 &do_transmit, session);
793 * Functions with this signature are called whenever we need
794 * to close a session due to a disconnect or failure to
795 * establish a connection.
797 * @param session session to close down
800 disconnect_session (struct Session *session)
802 struct Session *prev;
804 struct PendingMessage *pm;
807 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
809 "Disconnecting from `%4s' at %s.\n",
810 GNUNET_i2s (&session->target),
811 (session->connect_addr != NULL) ?
812 tcp_address_to_string (session->plugin,
813 session->connect_addr,
814 session->connect_alen) : "*");
816 /* remove from session list */
818 pos = session->plugin->sessions;
819 while (pos != session)
825 session->plugin->sessions = session->next;
827 prev->next = session->next;
830 if (session->transmit_handle != NULL)
832 GNUNET_CONNECTION_notify_transmit_ready_cancel
833 (session->transmit_handle);
834 session->transmit_handle = NULL;
836 while (NULL != (pm = session->pending_messages_head))
839 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
841 pm->transmit_cont != NULL
842 ? "Could not deliver message to `%4s'.\n"
843 : "Could not deliver message to `%4s', notifying.\n",
844 GNUNET_i2s (&session->target));
846 GNUNET_STATISTICS_update (session->plugin->env->stats,
847 gettext_noop ("# bytes currently in TCP buffers"),
848 - (int64_t) pm->message_size,
850 GNUNET_STATISTICS_update (session->plugin->env->stats,
851 gettext_noop ("# bytes discarded by TCP (disconnect)"),
854 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
855 session->pending_messages_tail,
857 if (NULL != pm->transmit_cont)
858 pm->transmit_cont (pm->transmit_cont_cls,
859 &session->target, GNUNET_SYSERR);
862 GNUNET_break (session->client != NULL);
863 if (session->receive_delay_task != GNUNET_SCHEDULER_NO_TASK)
865 GNUNET_SCHEDULER_cancel (session->receive_delay_task);
866 if (session->client != NULL)
867 GNUNET_SERVER_receive_done (session->client,
870 else if (session->client != NULL)
871 GNUNET_SERVER_client_drop (session->client);
872 GNUNET_STATISTICS_update (session->plugin->env->stats,
873 gettext_noop ("# TCP sessions active"),
876 GNUNET_free_non_null (session->connect_addr);
878 session->plugin->env->session_end (session->plugin->env->cls,
882 GNUNET_free (session);
887 * Given two otherwise equivalent sessions, pick the better one.
889 * @param s1 one session (also default)
890 * @param s2 other session
891 * @return "better" session (more active)
893 static struct Session *
894 select_better_session (struct Session *s1,
901 if ( (s1->expecting_welcome == GNUNET_NO) &&
902 (s2->expecting_welcome == GNUNET_YES) )
904 if ( (s1->expecting_welcome == GNUNET_YES) &&
905 (s2->expecting_welcome == GNUNET_NO) )
907 if (s1->last_activity.abs_value < s2->last_activity.abs_value)
909 if (s1->last_activity.abs_value > s2->last_activity.abs_value)
911 if ( (GNUNET_YES == s1->inbound) &&
912 (GNUNET_NO == s2->inbound) )
914 if ( (GNUNET_NO == s1->inbound) &&
915 (GNUNET_YES == s2->inbound) )
923 * Function that can be used by the transport service to transmit
924 * a message using the plugin. Note that in the case of a
925 * peer disconnecting, the continuation MUST be called
926 * prior to the disconnect notification itself. This function
927 * will be called with this peer's HELLO message to initiate
928 * a fresh connection to another peer.
931 * @param target who should receive this message
932 * @param msg the message to transmit
933 * @param msgbuf_size number of bytes in 'msg'
934 * @param priority how important is the message (most plugins will
935 * ignore message priority and just FIFO)
936 * @param timeout how long to wait at most for the transmission (does not
937 * require plugins to discard the message after the timeout,
938 * just advisory for the desired delay; most plugins will ignore
940 * @param session which session must be used (or NULL for "any")
941 * @param addr the address to use (can be NULL if the plugin
942 * is "on its own" (i.e. re-use existing TCP connection))
943 * @param addrlen length of the address in bytes
944 * @param force_address GNUNET_YES if the plugin MUST use the given address,
945 * GNUNET_NO means the plugin may use any other address and
946 * GNUNET_SYSERR means that only reliable existing
947 * bi-directional connections should be used (regardless
949 * @param cont continuation to call once the message has
950 * been transmitted (or if the transport is ready
951 * for the next transmission call; or if the
952 * peer disconnected...); can be NULL
953 * @param cont_cls closure for cont
954 * @return number of bytes used (on the physical network, with overheads);
955 * -1 on hard errors (i.e. address invalid); 0 is a legal value
956 * and does NOT mean that the message was not transmitted (DV and NAT)
959 tcp_plugin_send (void *cls,
960 const struct GNUNET_PeerIdentity *target,
964 struct GNUNET_TIME_Relative timeout,
965 struct Session *session,
969 GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
971 struct Plugin *plugin = cls;
972 struct Session *cand_session;
973 struct Session *next;
974 struct PendingMessage *pm;
975 struct GNUNET_CONNECTION_Handle *sa;
979 struct sockaddr_in a4;
980 struct sockaddr_in6 a6;
981 const struct IPv4TcpAddress *t4;
982 const struct IPv6TcpAddress *t6;
983 unsigned int is_natd;
985 GNUNET_STATISTICS_update (plugin->env->stats,
986 gettext_noop ("# bytes TCP was asked to transmit"),
989 /* FIXME: we could do this cheaper with a hash table
990 where we could restrict the iteration to entries that match
991 the target peer... */
996 next = plugin->sessions;
997 while (NULL != (session = next))
999 next = session->next;
1000 GNUNET_assert (session->client != NULL);
1001 if (0 != memcmp (target,
1003 sizeof (struct GNUNET_PeerIdentity)))
1005 if ( ( (GNUNET_SYSERR == force_address) &&
1006 (session->expecting_welcome == GNUNET_NO) ) ||
1007 (GNUNET_NO == force_address) )
1009 cand_session = select_better_session (cand_session,
1013 if (GNUNET_SYSERR == force_address)
1015 GNUNET_break (GNUNET_YES == force_address);
1021 if ( (addrlen != session->connect_alen) &&
1022 (session->is_nat == GNUNET_NO) )
1024 if ((0 != memcmp (session->connect_addr,
1026 addrlen)) && (session->is_nat == GNUNET_NO))
1028 cand_session = select_better_session (cand_session,
1031 session = cand_session;
1033 if ( (session == NULL) &&
1037 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1039 "Asked to transmit to `%4s' without address and I have no existing connection (failing).\n",
1040 GNUNET_i2s (target));
1042 GNUNET_STATISTICS_update (plugin->env->stats,
1043 gettext_noop ("# bytes discarded by TCP (no address and no connection)"),
1048 if (session == NULL)
1050 if (addrlen == sizeof (struct IPv6TcpAddress))
1054 memset (&a6, 0, sizeof (a6));
1055 #if HAVE_SOCKADDR_IN_SIN_LEN
1056 a6.sin6_len = sizeof (a6);
1058 a6.sin6_family = AF_INET6;
1059 a6.sin6_port = t6->t6_port;
1060 if (t6->t6_port == 0)
1061 is_natd = GNUNET_YES;
1062 memcpy (&a6.sin6_addr,
1064 sizeof (struct in6_addr));
1068 else if (addrlen == sizeof (struct IPv4TcpAddress))
1072 memset (&a4, 0, sizeof (a4));
1073 #if HAVE_SOCKADDR_IN_SIN_LEN
1074 a4.sin_len = sizeof (a4);
1076 a4.sin_family = AF_INET;
1077 a4.sin_port = t4->t4_port;
1078 if (t4->t4_port == 0)
1079 is_natd = GNUNET_YES;
1080 a4.sin_addr.s_addr = t4->ipv4_addr;
1086 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
1088 _("Address of unexpected length: %u\n"),
1094 if ((is_natd == GNUNET_YES) && (addrlen == sizeof (struct IPv6TcpAddress)))
1095 return -1; /* NAT client only works with IPv4 addresses */
1096 if (0 == plugin->max_connections)
1097 return -1; /* saturated */
1099 if ( (is_natd == GNUNET_YES) &&
1100 (NULL != plugin->nat) &&
1101 (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns,
1102 &target->hashPubKey)) )
1105 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1107 _("Found valid IPv4 NAT address (creating session)!\n"));
1109 session = create_session (plugin,
1114 /* create new message entry */
1115 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msgbuf_size);
1116 /* FIXME: the memset of this malloc can be up to 2% of our total runtime */
1117 pm->msg = (const char*) &pm[1];
1118 memcpy (&pm[1], msg, msgbuf_size);
1119 /* FIXME: this memcpy can be up to 7% of our total run-time
1120 (for transport service) */
1121 pm->message_size = msgbuf_size;
1122 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1123 pm->transmit_cont = cont;
1124 pm->transmit_cont_cls = cont_cls;
1126 /* append pm to pending_messages list */
1127 GNUNET_CONTAINER_DLL_insert_after (session->pending_messages_head,
1128 session->pending_messages_tail,
1129 session->pending_messages_tail,
1132 GNUNET_assert(GNUNET_CONTAINER_multihashmap_put(plugin->nat_wait_conns,
1133 &target->hashPubKey,
1135 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY) == GNUNET_OK);
1137 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1139 "Created NAT WAIT connection to `%4s' at `%s'\n",
1140 GNUNET_i2s (target),
1141 GNUNET_a2s (sb, sbs));
1143 GNUNET_NAT_run_client (plugin->nat, &a4);
1146 if ( (is_natd == GNUNET_YES) &&
1147 (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns,
1148 &target->hashPubKey)) )
1150 /* Only do one NAT punch attempt per peer identity */
1153 sa = GNUNET_CONNECTION_create_from_sockaddr (af, sb, sbs);
1157 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1159 "Failed to create connection to `%4s' at `%s'\n",
1160 GNUNET_i2s (target),
1161 GNUNET_a2s (sb, sbs));
1163 GNUNET_STATISTICS_update (plugin->env->stats,
1164 gettext_noop ("# bytes discarded by TCP (failed to connect)"),
1169 GNUNET_assert (0 != plugin->max_connections);
1170 plugin->max_connections--;
1172 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1174 "Asked to transmit to `%4s', creating fresh session using address `%s'.\n",
1175 GNUNET_i2s (target),
1176 GNUNET_a2s (sb, sbs));
1178 session = create_session (plugin,
1180 GNUNET_SERVER_connect_socket (plugin->server,
1183 session->connect_addr = GNUNET_malloc (addrlen);
1184 memcpy (session->connect_addr,
1187 session->connect_alen = addrlen;
1189 GNUNET_assert (session != NULL);
1190 GNUNET_assert (session->client != NULL);
1191 GNUNET_STATISTICS_update (plugin->env->stats,
1192 gettext_noop ("# bytes currently in TCP buffers"),
1195 /* create new message entry */
1196 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msgbuf_size);
1197 pm->msg = (const char*) &pm[1];
1198 memcpy (&pm[1], msg, msgbuf_size);
1199 pm->message_size = msgbuf_size;
1200 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1201 pm->transmit_cont = cont;
1202 pm->transmit_cont_cls = cont_cls;
1204 /* append pm to pending_messages list */
1205 GNUNET_CONTAINER_DLL_insert_after (session->pending_messages_head,
1206 session->pending_messages_tail,
1207 session->pending_messages_tail,
1210 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1212 "Asked to transmit %u bytes to `%s', added message to list.\n",
1214 GNUNET_i2s (target));
1216 process_pending_messages (session);
1222 * Function that can be called to force a disconnect from the
1223 * specified neighbour. This should also cancel all previously
1224 * scheduled transmissions. Obviously the transmission may have been
1225 * partially completed already, which is OK. The plugin is supposed
1226 * to close the connection (if applicable) and no longer call the
1227 * transmit continuation(s).
1229 * Finally, plugin MUST NOT call the services's receive function to
1230 * notify the service that the connection to the specified target was
1231 * closed after a getting this call.
1233 * @param cls closure
1234 * @param target peer for which the last transmission is
1238 tcp_plugin_disconnect (void *cls,
1239 const struct GNUNET_PeerIdentity *target)
1241 struct Plugin *plugin = cls;
1242 struct Session *session;
1243 struct Session *next;
1244 struct PendingMessage *pm;
1247 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1249 "Asked to cancel session with `%4s'\n",
1250 GNUNET_i2s (target));
1252 next = plugin->sessions;
1253 while (NULL != (session = next))
1255 next = session->next;
1256 if (0 != memcmp (target,
1258 sizeof (struct GNUNET_PeerIdentity)))
1260 pm = session->pending_messages_head;
1263 pm->transmit_cont = NULL;
1264 pm->transmit_cont_cls = NULL;
1267 GNUNET_STATISTICS_update (session->plugin->env->stats,
1268 gettext_noop ("# transport-service disconnect requests for TCP"),
1271 disconnect_session (session);
1277 * Context for address to string conversion.
1279 struct PrettyPrinterContext
1282 * Function to call with the result.
1284 GNUNET_TRANSPORT_AddressStringCallback asc;
1287 * Clsoure for 'asc'.
1292 * Port to add after the IP address.
1299 * Append our port and forward the result.
1301 * @param cls the 'struct PrettyPrinterContext*'
1302 * @param hostname hostname part of the address
1305 append_port (void *cls, const char *hostname)
1307 struct PrettyPrinterContext *ppc = cls;
1310 if (hostname == NULL)
1312 ppc->asc (ppc->asc_cls, NULL);
1316 GNUNET_asprintf (&ret, "%s:%d", hostname, ppc->port);
1317 ppc->asc (ppc->asc_cls, ret);
1323 * Convert the transports address to a nice, human-readable
1326 * @param cls closure
1327 * @param type name of the transport that generated the address
1328 * @param addr one of the addresses of the host, NULL for the last address
1329 * the specific address format depends on the transport
1330 * @param addrlen length of the address
1331 * @param numeric should (IP) addresses be displayed in numeric form?
1332 * @param timeout after how long should we give up?
1333 * @param asc function to call on each string
1334 * @param asc_cls closure for asc
1337 tcp_plugin_address_pretty_printer (void *cls,
1342 struct GNUNET_TIME_Relative timeout,
1343 GNUNET_TRANSPORT_AddressStringCallback asc,
1346 struct PrettyPrinterContext *ppc;
1349 struct sockaddr_in a4;
1350 struct sockaddr_in6 a6;
1351 const struct IPv4TcpAddress *t4;
1352 const struct IPv6TcpAddress *t6;
1355 if (addrlen == sizeof (struct IPv6TcpAddress))
1358 memset (&a6, 0, sizeof (a6));
1359 a6.sin6_family = AF_INET6;
1360 a6.sin6_port = t6->t6_port;
1361 memcpy (&a6.sin6_addr,
1363 sizeof (struct in6_addr));
1364 port = ntohs (t6->t6_port);
1368 else if (addrlen == sizeof (struct IPv4TcpAddress))
1371 memset (&a4, 0, sizeof (a4));
1372 a4.sin_family = AF_INET;
1373 a4.sin_port = t4->t4_port;
1374 a4.sin_addr.s_addr = t4->ipv4_addr;
1375 port = ntohs (t4->t4_port);
1381 /* invalid address */
1382 GNUNET_break_op (0);
1383 asc (asc_cls, NULL);
1386 ppc = GNUNET_malloc (sizeof (struct PrettyPrinterContext));
1388 ppc->asc_cls = asc_cls;
1390 GNUNET_RESOLVER_hostname_get (sb,
1392 !numeric, timeout, &append_port, ppc);
1397 * Check if the given port is plausible (must be either our listen
1398 * port or our advertised port), or any port if we are behind NAT
1399 * and do not have a port open. If it is neither, we return
1402 * @param plugin global variables
1403 * @param in_port port number to check
1404 * @return GNUNET_OK if port is either open_port or adv_port
1407 check_port (struct Plugin *plugin,
1410 if ((in_port == plugin->adv_port) || (in_port == plugin->open_port))
1412 return GNUNET_SYSERR;
1417 * Function that will be called to check if a binary address for this
1418 * plugin is well-formed and corresponds to an address for THIS peer
1419 * (as per our configuration). Naturally, if absolutely necessary,
1420 * plugins can be a bit conservative in their answer, but in general
1421 * plugins should make sure that the address does not redirect
1422 * traffic to a 3rd party that might try to man-in-the-middle our
1425 * @param cls closure, our 'struct Plugin*'
1426 * @param addr pointer to the address
1427 * @param addrlen length of addr
1428 * @return GNUNET_OK if this is a plausible address for this peer
1429 * and transport, GNUNET_SYSERR if not
1432 tcp_plugin_check_address (void *cls,
1436 struct Plugin *plugin = cls;
1437 struct IPv4TcpAddress *v4;
1438 struct IPv6TcpAddress *v6;
1440 if ((addrlen != sizeof (struct IPv4TcpAddress)) &&
1441 (addrlen != sizeof (struct IPv6TcpAddress)))
1443 GNUNET_break_op (0);
1444 return GNUNET_SYSERR;
1446 if (addrlen == sizeof (struct IPv4TcpAddress))
1448 v4 = (struct IPv4TcpAddress *) addr;
1450 check_port (plugin, ntohs (v4->t4_port)))
1451 return GNUNET_SYSERR;
1453 GNUNET_NAT_test_address (plugin->nat,
1454 &v4->ipv4_addr, sizeof (struct in_addr)))
1455 return GNUNET_SYSERR;
1459 v6 = (struct IPv6TcpAddress *) addr;
1460 if (IN6_IS_ADDR_LINKLOCAL (&v6->ipv6_addr))
1462 GNUNET_break_op (0);
1463 return GNUNET_SYSERR;
1466 check_port (plugin, ntohs (v6->t6_port)))
1467 return GNUNET_SYSERR;
1469 GNUNET_NAT_test_address (plugin->nat,
1470 &v6->ipv6_addr, sizeof (struct in6_addr)))
1471 return GNUNET_SYSERR;
1478 * We've received a nat probe from this peer via TCP. Finish
1479 * creating the client session and resume sending of queued
1482 * @param cls closure
1483 * @param client identification of the client
1484 * @param message the actual message
1487 handle_tcp_nat_probe (void *cls,
1488 struct GNUNET_SERVER_Client *client,
1489 const struct GNUNET_MessageHeader *message)
1491 struct Plugin *plugin = cls;
1492 struct Session *session;
1493 const struct TCP_NAT_ProbeMessage *tcp_nat_probe;
1496 struct IPv4TcpAddress *t4;
1497 struct IPv6TcpAddress *t6;
1498 const struct sockaddr_in *s4;
1499 const struct sockaddr_in6 *s6;
1502 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1504 "received NAT probe\n");
1506 /* We have received a TCP NAT probe, meaning we (hopefully) initiated
1507 * a connection to this peer by running gnunet-nat-client. This peer
1508 * received the punch message and now wants us to use the new connection
1509 * as the default for that peer. Do so and then send a WELCOME message
1510 * so we can really be connected!
1512 if (ntohs(message->size) != sizeof(struct TCP_NAT_ProbeMessage))
1515 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1519 tcp_nat_probe = (const struct TCP_NAT_ProbeMessage *)message;
1520 if (0 == memcmp (&tcp_nat_probe->clientIdentity,
1521 plugin->env->my_identity,
1522 sizeof (struct GNUNET_PeerIdentity)))
1524 /* refuse connections from ourselves */
1525 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1529 session = GNUNET_CONTAINER_multihashmap_get(plugin->nat_wait_conns,
1530 &tcp_nat_probe->clientIdentity.hashPubKey);
1531 if (session == NULL)
1534 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1536 "Did NOT find session for NAT probe!\n");
1538 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1542 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1544 "Found session for NAT probe!\n");
1546 GNUNET_assert(GNUNET_CONTAINER_multihashmap_remove(plugin->nat_wait_conns,
1547 &tcp_nat_probe->clientIdentity.hashPubKey,
1548 session) == GNUNET_YES);
1550 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1553 GNUNET_free (session);
1554 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1558 GNUNET_SERVER_client_keep (client);
1559 session->client = client;
1560 session->last_activity = GNUNET_TIME_absolute_get ();
1561 session->inbound = GNUNET_NO;
1564 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1566 "Found address `%s' for incoming connection\n",
1567 GNUNET_a2s (vaddr, alen));
1569 switch (((const struct sockaddr *)vaddr)->sa_family)
1573 t4 = GNUNET_malloc (sizeof (struct IPv4TcpAddress));
1574 t4->t4_port = s4->sin_port;
1575 t4->ipv4_addr = s4->sin_addr.s_addr;
1576 session->connect_addr = t4;
1577 session->connect_alen = sizeof (struct IPv4TcpAddress);
1581 t6 = GNUNET_malloc (sizeof (struct IPv6TcpAddress));
1582 t6->t6_port = s6->sin6_port;
1583 memcpy (&t6->ipv6_addr,
1585 sizeof (struct in6_addr));
1586 session->connect_addr = t6;
1587 session->connect_alen = sizeof (struct IPv6TcpAddress);
1590 GNUNET_break_op (0);
1592 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1594 "Bad address for incoming connection!\n");
1596 GNUNET_free (vaddr);
1597 GNUNET_SERVER_client_drop (client);
1598 GNUNET_free (session);
1599 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1602 GNUNET_free (vaddr);
1604 session->next = plugin->sessions;
1605 plugin->sessions = session;
1606 GNUNET_STATISTICS_update (plugin->env->stats,
1607 gettext_noop ("# TCP sessions active"),
1610 process_pending_messages (session);
1611 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1616 * We've received a welcome from this peer via TCP. Possibly create a
1617 * fresh client record and send back our welcome.
1619 * @param cls closure
1620 * @param client identification of the client
1621 * @param message the actual message
1624 handle_tcp_welcome (void *cls,
1625 struct GNUNET_SERVER_Client *client,
1626 const struct GNUNET_MessageHeader *message)
1628 struct Plugin *plugin = cls;
1629 const struct WelcomeMessage *wm = (const struct WelcomeMessage *) message;
1630 struct Session *session;
1633 struct IPv4TcpAddress *t4;
1634 struct IPv6TcpAddress *t6;
1635 const struct sockaddr_in *s4;
1636 const struct sockaddr_in6 *s6;
1638 if (0 == memcmp (&wm->clientIdentity,
1639 plugin->env->my_identity,
1640 sizeof (struct GNUNET_PeerIdentity)))
1642 /* refuse connections from ourselves */
1643 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1647 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1649 "Received %s message from `%4s'.\n",
1651 GNUNET_i2s (&wm->clientIdentity));
1653 GNUNET_STATISTICS_update (plugin->env->stats,
1654 gettext_noop ("# TCP WELCOME messages received"),
1657 session = find_session_by_client (plugin, client);
1659 if (session == NULL)
1662 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1664 "Received %s message from a `%4s', creating new session\n",
1666 GNUNET_i2s (&wm->clientIdentity));
1668 GNUNET_SERVER_client_keep (client);
1669 session = create_session (plugin,
1670 &wm->clientIdentity,
1673 session->inbound = GNUNET_YES;
1675 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1678 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1680 "Found address `%s' for incoming connection\n",
1681 GNUNET_a2s (vaddr, alen));
1683 if (alen == sizeof (struct sockaddr_in))
1686 t4 = GNUNET_malloc (sizeof (struct IPv4TcpAddress));
1687 t4->t4_port = s4->sin_port;
1688 t4->ipv4_addr = s4->sin_addr.s_addr;
1689 session->connect_addr = t4;
1690 session->connect_alen = sizeof (struct IPv4TcpAddress);
1692 else if (alen == sizeof (struct sockaddr_in6))
1695 t6 = GNUNET_malloc (sizeof (struct IPv6TcpAddress));
1696 t6->t6_port = s6->sin6_port;
1697 memcpy (&t6->ipv6_addr,
1699 sizeof (struct in6_addr));
1700 session->connect_addr = t6;
1701 session->connect_alen = sizeof (struct IPv6TcpAddress);
1704 GNUNET_free (vaddr);
1709 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1711 "Did not obtain TCP socket address for incoming connection\n");
1714 process_pending_messages (session);
1720 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1722 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1724 "Found address `%s' (already have session)\n",
1725 GNUNET_a2s (vaddr, alen));
1726 GNUNET_free (vaddr);
1731 if (session->expecting_welcome != GNUNET_YES)
1733 GNUNET_break_op (0);
1734 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1737 session->last_activity = GNUNET_TIME_absolute_get ();
1738 session->expecting_welcome = GNUNET_NO;
1739 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1744 * Task to signal the server that we can continue
1745 * receiving from the TCP client now.
1747 * @param cls the 'struct Session*'
1748 * @param tc task context (unused)
1751 delayed_done (void *cls,
1752 const struct GNUNET_SCHEDULER_TaskContext *tc)
1754 struct Session *session = cls;
1755 struct GNUNET_TIME_Relative delay;
1757 session->receive_delay_task = GNUNET_SCHEDULER_NO_TASK;
1758 delay = session->plugin->env->receive (session->plugin->env->cls,
1764 if (delay.rel_value == 0)
1765 GNUNET_SERVER_receive_done (session->client, GNUNET_OK);
1767 session->receive_delay_task =
1768 GNUNET_SCHEDULER_add_delayed (delay, &delayed_done, session);
1773 * We've received data for this peer via TCP. Unbox,
1774 * compute latency and forward.
1776 * @param cls closure
1777 * @param client identification of the client
1778 * @param message the actual message
1781 handle_tcp_data (void *cls,
1782 struct GNUNET_SERVER_Client *client,
1783 const struct GNUNET_MessageHeader *message)
1785 struct Plugin *plugin = cls;
1786 struct Session *session;
1787 struct GNUNET_TIME_Relative delay;
1790 type = ntohs (message->type);
1791 if ( (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME == type) ||
1792 (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE == type) )
1794 /* We don't want to propagate WELCOME and NAT Probe messages up! */
1795 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1798 session = find_session_by_client (plugin, client);
1799 if ( (NULL == session) || (GNUNET_YES == session->expecting_welcome) )
1801 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1804 session->last_activity = GNUNET_TIME_absolute_get ();
1806 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1808 "Passing %u bytes of type %u from `%4s' to transport service.\n",
1809 (unsigned int) ntohs (message->size),
1810 (unsigned int) ntohs (message->type),
1811 GNUNET_i2s (&session->target));
1813 GNUNET_STATISTICS_update (plugin->env->stats,
1814 gettext_noop ("# bytes received via TCP"),
1815 ntohs (message->size),
1817 struct GNUNET_TRANSPORT_ATS_Information distance[2];
1818 distance[0].type = htonl (GNUNET_TRANSPORT_ATS_QUALITY_NET_DISTANCE);
1819 distance[0].value = htonl (1);
1820 distance[1].type = htonl (GNUNET_TRANSPORT_ATS_ARRAY_TERMINATOR);
1821 distance[1].value = htonl (0);
1822 delay = plugin->env->receive (plugin->env->cls, &session->target, message,
1823 (const struct GNUNET_TRANSPORT_ATS_Information *) &distance,
1826 (GNUNET_YES == session->inbound) ? NULL : session->connect_addr,
1827 (GNUNET_YES == session->inbound) ? 0 : session->connect_alen);
1828 if (delay.rel_value == 0)
1830 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1835 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1837 "Throttling receiving from `%s' for %llu ms\n",
1838 GNUNET_i2s (&session->target),
1839 (unsigned long long) delay.rel_value);
1841 GNUNET_SERVER_disable_receive_done_warning (client);
1842 session->receive_delay_task =
1843 GNUNET_SCHEDULER_add_delayed (delay, &delayed_done, session);
1849 * Functions with this signature are called whenever a peer
1850 * is disconnected on the network level.
1852 * @param cls closure
1853 * @param client identification of the client
1856 disconnect_notify (void *cls,
1857 struct GNUNET_SERVER_Client *client)
1859 struct Plugin *plugin = cls;
1860 struct Session *session;
1864 plugin->max_connections++;
1865 session = find_session_by_client (plugin, client);
1866 if (session == NULL)
1867 return; /* unknown, nothing to do */
1869 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1871 "Destroying session of `%4s' with %s due to network-level disconnect.\n",
1872 GNUNET_i2s (&session->target),
1873 (session->connect_addr != NULL) ?
1874 tcp_address_to_string (session->plugin,
1875 session->connect_addr,
1876 session->connect_alen) : "*");
1878 GNUNET_STATISTICS_update (session->plugin->env->stats,
1879 gettext_noop ("# network-level TCP disconnect events"),
1882 disconnect_session (session);
1887 * We can now send a probe message, copy into buffer to really send.
1889 * @param cls closure, a struct TCPProbeContext
1890 * @param size max size to copy
1891 * @param buf buffer to copy message to
1892 * @return number of bytes copied into buf
1895 notify_send_probe (void *cls,
1899 struct TCPProbeContext *tcp_probe_ctx = cls;
1900 struct Plugin *plugin = tcp_probe_ctx->plugin;
1903 tcp_probe_ctx->transmit_handle = NULL;
1904 GNUNET_CONTAINER_DLL_remove (plugin->probe_head,
1909 GNUNET_CONNECTION_destroy (tcp_probe_ctx->sock, GNUNET_NO);
1910 GNUNET_free(tcp_probe_ctx);
1913 GNUNET_assert(size >= sizeof(tcp_probe_ctx->message));
1914 memcpy(buf, &tcp_probe_ctx->message, sizeof(tcp_probe_ctx->message));
1915 GNUNET_SERVER_connect_socket (tcp_probe_ctx->plugin->server,
1916 tcp_probe_ctx->sock);
1917 ret = sizeof(tcp_probe_ctx->message);
1918 GNUNET_free(tcp_probe_ctx);
1924 * Function called by the NAT subsystem suggesting another peer wants
1925 * to connect to us via connection reversal. Try to connect back to the
1928 * @param cls closure
1929 * @param addr address to try
1930 * @param addrlen number of bytes in addr
1933 try_connection_reversal (void *cls,
1934 const struct sockaddr *addr,
1937 struct Plugin *plugin = cls;
1938 struct GNUNET_CONNECTION_Handle *sock;
1939 struct TCPProbeContext *tcp_probe_ctx;
1942 * We have received an ICMP response, ostensibly from a peer
1943 * that wants to connect to us! Send a message to establish a connection.
1945 sock = GNUNET_CONNECTION_create_from_sockaddr (AF_INET,
1950 /* failed for some odd reason (out of sockets?); ignore attempt */
1954 /* FIXME: do we need to track these probe context objects so that
1955 we can clean them up on plugin unload? */
1957 = GNUNET_malloc(sizeof(struct TCPProbeContext));
1958 tcp_probe_ctx->message.header.size
1959 = htons(sizeof(struct TCP_NAT_ProbeMessage));
1960 tcp_probe_ctx->message.header.type
1961 = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE);
1962 memcpy (&tcp_probe_ctx->message.clientIdentity,
1963 plugin->env->my_identity,
1964 sizeof(struct GNUNET_PeerIdentity));
1965 tcp_probe_ctx->plugin = plugin;
1966 tcp_probe_ctx->sock = sock;
1967 GNUNET_CONTAINER_DLL_insert (plugin->probe_head,
1970 tcp_probe_ctx->transmit_handle
1971 = GNUNET_CONNECTION_notify_transmit_ready (sock,
1972 ntohs (tcp_probe_ctx->message.header.size),
1973 GNUNET_TIME_UNIT_FOREVER_REL,
1974 ¬ify_send_probe, tcp_probe_ctx);
1980 * Entry point for the plugin.
1982 * @param cls closure, the 'struct GNUNET_TRANSPORT_PluginEnvironment*'
1983 * @return the 'struct GNUNET_TRANSPORT_PluginFunctions*' or NULL on error
1986 libgnunet_plugin_transport_tcp_init (void *cls)
1988 static const struct GNUNET_SERVER_MessageHandler my_handlers[] = {
1989 {&handle_tcp_welcome, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME,
1990 sizeof (struct WelcomeMessage)},
1991 {&handle_tcp_nat_probe, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE, sizeof (struct TCP_NAT_ProbeMessage)},
1992 {&handle_tcp_data, NULL, GNUNET_MESSAGE_TYPE_ALL, 0},
1995 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
1996 struct GNUNET_TRANSPORT_PluginFunctions *api;
1997 struct Plugin *plugin;
1998 struct GNUNET_SERVICE_Context *service;
1999 unsigned long long aport;
2000 unsigned long long bport;
2001 unsigned long long max_connections;
2003 struct GNUNET_TIME_Relative idle_timeout;
2005 struct sockaddr **addrs;
2006 socklen_t *addrlens;
2009 GNUNET_CONFIGURATION_get_value_number (env->cfg,
2013 max_connections = 128;
2017 GNUNET_CONFIGURATION_get_value_number (env->cfg,
2023 GNUNET_CONFIGURATION_get_value_number (env->cfg,
2029 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2031 _("Require valid port number for service `%s' in configuration!\n"),
2041 service = GNUNET_SERVICE_start ("transport-tcp", env->cfg);
2042 if (service == NULL)
2044 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING,
2046 _("Failed to start service.\n"));
2055 plugin = GNUNET_malloc (sizeof (struct Plugin));
2056 plugin->max_connections = max_connections;
2057 plugin->open_port = bport;
2058 plugin->adv_port = aport;
2060 plugin->lsock = NULL;
2061 if ( (service != NULL) &&
2063 (ret = GNUNET_SERVICE_get_server_addresses ("transport-tcp",
2068 plugin->nat = GNUNET_NAT_register (env->cfg,
2072 (const struct sockaddr **) addrs,
2074 &tcp_nat_port_map_callback,
2075 &try_connection_reversal,
2078 GNUNET_free (addrs[--ret]);
2079 GNUNET_free_non_null (addrs);
2080 GNUNET_free_non_null (addrlens);
2084 plugin->nat = GNUNET_NAT_register (env->cfg,
2089 &try_connection_reversal,
2092 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
2094 api->send = &tcp_plugin_send;
2095 api->disconnect = &tcp_plugin_disconnect;
2096 api->address_pretty_printer = &tcp_plugin_address_pretty_printer;
2097 api->check_address = &tcp_plugin_check_address;
2098 api->address_to_string = &tcp_address_to_string;
2099 plugin->service = service;
2100 if (service != NULL)
2102 plugin->server = GNUNET_SERVICE_get_server (service);
2107 GNUNET_CONFIGURATION_get_value_time (env->cfg,
2112 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2114 _("Failed to find option %s in section %s!\n"),
2117 if (plugin->nat != NULL)
2118 GNUNET_NAT_unregister (plugin->nat);
2119 GNUNET_free (plugin);
2123 plugin->server = GNUNET_SERVER_create_with_sockets (&plugin_tcp_access_check, plugin, NULL,
2124 idle_timeout, GNUNET_YES);
2126 plugin->handlers = GNUNET_malloc (sizeof (my_handlers));
2127 memcpy (plugin->handlers, my_handlers, sizeof (my_handlers));
2129 i < sizeof (my_handlers) / sizeof (struct GNUNET_SERVER_MessageHandler);
2131 plugin->handlers[i].callback_cls = plugin;
2132 GNUNET_SERVER_add_handlers (plugin->server, plugin->handlers);
2133 GNUNET_SERVER_disconnect_notify (plugin->server,
2136 plugin->nat_wait_conns = GNUNET_CONTAINER_multihashmap_create(16);
2138 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2140 _("TCP transport listening on port %llu\n"),
2143 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2145 _("TCP transport not listening on any port (client only)\n"));
2147 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2149 _("TCP transport advertises itself as being on port %llu\n"),
2156 * Exit point from the plugin.
2159 libgnunet_plugin_transport_tcp_done (void *cls)
2161 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
2162 struct Plugin *plugin = api->cls;
2163 struct Session *session;
2164 struct TCPProbeContext *tcp_probe;
2166 while (NULL != (session = plugin->sessions))
2167 disconnect_session (session);
2168 if (plugin->service != NULL)
2169 GNUNET_SERVICE_stop (plugin->service);
2171 GNUNET_SERVER_destroy (plugin->server);
2172 GNUNET_free (plugin->handlers);
2173 if (plugin->nat != NULL)
2174 GNUNET_NAT_unregister (plugin->nat);
2175 while (NULL != (tcp_probe = plugin->probe_head))
2177 GNUNET_CONTAINER_DLL_remove (plugin->probe_head,
2180 GNUNET_CONNECTION_destroy (tcp_probe->sock, GNUNET_NO);
2181 GNUNET_free (tcp_probe);
2183 GNUNET_CONTAINER_multihashmap_destroy (plugin->nat_wait_conns);
2184 GNUNET_free (plugin);
2189 /* end of plugin_transport_tcp.c */