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_os_lib.h"
30 #include "gnunet_protocols.h"
31 #include "gnunet_resolver_service.h"
32 #include "gnunet_server_lib.h"
33 #include "gnunet_service_lib.h"
34 #include "gnunet_signatures.h"
35 #include "gnunet_statistics_service.h"
36 #include "gnunet_transport_service.h"
37 #include "plugin_transport.h"
38 #include "transport.h"
40 #define DEBUG_TCP GNUNET_NO
41 #define DEBUG_TCP_NAT GNUNET_NO
44 * How long until we give up on transmitting the welcome message?
46 #define HOSTNAME_RESOLVE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
50 * Initial handshake message for a session.
55 * Type is GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME.
57 struct GNUNET_MessageHeader header;
60 * Identity of the node connecting (TCP client)
62 struct GNUNET_PeerIdentity clientIdentity;
67 * Basically a WELCOME message, but with the purpose
68 * of giving the waiting peer a client handle to use
70 struct TCP_NAT_ProbeMessage
73 * Type is GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE.
75 struct GNUNET_MessageHeader header;
78 * Identity of the sender of the message.
80 struct GNUNET_PeerIdentity clientIdentity;
85 * Context for sending a NAT probe via TCP.
87 struct TCPProbeContext
92 struct GNUNET_CONNECTION_Handle *sock;
97 struct TCP_NAT_ProbeMessage message;
100 * Handle to the transmission.
102 struct GNUNET_CONNECTION_TransmitHandle *transmit_handle;
105 * Transport plugin handle.
107 struct Plugin *plugin;
112 * Network format for IPv4 addresses.
114 struct IPv4TcpAddress
117 * IPv4 address, in network byte order.
119 uint32_t ipv4_addr GNUNET_PACKED;
122 * Port number, in network byte order.
124 uint16_t t_port GNUNET_PACKED;
130 * Network format for IPv6 addresses.
132 struct IPv6TcpAddress
137 struct in6_addr ipv6_addr GNUNET_PACKED;
140 * Port number, in network byte order.
142 uint16_t t6_port GNUNET_PACKED;
147 * Encapsulation of all of the state of the plugin.
153 * Local network addresses (actual IP address follows this struct).
154 * PORT is NOT included!
160 * This is a doubly linked list.
162 struct LocalAddrList *next;
165 * This is a doubly linked list.
167 struct LocalAddrList *prev;
170 * Number of bytes of the address that follow
178 * Information kept for each message that is yet to
181 struct PendingMessage
185 * This is a doubly-linked list.
187 struct PendingMessage *next;
190 * This is a doubly-linked list.
192 struct PendingMessage *prev;
195 * The pending message
200 * Continuation function to call once the message
201 * has been sent. Can be NULL if there is no
202 * continuation to call.
204 GNUNET_TRANSPORT_TransmitContinuation transmit_cont;
207 * Closure for transmit_cont.
209 void *transmit_cont_cls;
212 * Timeout value for the pending message.
214 struct GNUNET_TIME_Absolute timeout;
217 * So that the gnunet-service-transport can group messages together,
218 * these pending messages need to accept a message buffer and size
219 * instead of just a GNUNET_MessageHeader.
227 * Session handle for TCP connections.
235 struct SessionHeader header;
238 * Stored in a linked list.
240 struct Session *next;
243 * Pointer to the global plugin struct.
245 struct Plugin *plugin;
248 * The client (used to identify this connection)
250 struct GNUNET_SERVER_Client *client;
253 * Messages currently pending for transmission
254 * to this peer, if any.
256 struct PendingMessage *pending_messages_head;
259 * Messages currently pending for transmission
260 * to this peer, if any.
262 struct PendingMessage *pending_messages_tail;
265 * Handle for pending transmission request.
267 struct GNUNET_CONNECTION_TransmitHandle *transmit_handle;
270 * To whom are we talking to (set to our identity
271 * if we are still waiting for the welcome message)
273 struct GNUNET_PeerIdentity target;
276 * ID of task used to delay receiving more to throttle sender.
278 GNUNET_SCHEDULER_TaskIdentifier receive_delay_task;
281 * Address of the other peer (either based on our 'connect'
282 * call or on our 'accept' call).
287 * Last activity on this connection. Used to select preferred
290 struct GNUNET_TIME_Absolute last_activity;
293 * Length of connect_addr.
298 * Are we still expecting the welcome message? (GNUNET_YES/GNUNET_NO)
300 int expecting_welcome;
303 * Was this a connection that was inbound (we accepted)? (GNUNET_YES/GNUNET_NO)
311 * Encapsulation of all of the state of the plugin.
318 struct GNUNET_TRANSPORT_PluginEnvironment *env;
323 struct GNUNET_CONNECTION_Handle *lsock;
326 * stdout pipe handle for the gnunet-nat-server process
328 struct GNUNET_DISK_PipeHandle *server_stdout;
331 * stdout file handle (for reading) for the gnunet-nat-server process
333 const struct GNUNET_DISK_FileHandle *server_stdout_handle;
336 * ID of select gnunet-nat-server stdout read task
338 GNUNET_SCHEDULER_TaskIdentifier server_read_task;
341 * The process id of the server process (if behind NAT)
346 * List of open TCP sessions.
348 struct Session *sessions;
351 * Handle to the network service.
353 struct GNUNET_SERVICE_Context *service;
356 * Handle to the server for this service.
358 struct GNUNET_SERVER_Handle *server;
361 * Copy of the handler array where the closures are
362 * set to this struct's instance.
364 struct GNUNET_SERVER_MessageHandler *handlers;
367 * Handle for request of hostname resolution, non-NULL if pending.
369 struct GNUNET_RESOLVER_RequestHandle *hostname_dns;
372 * Map of peers we have tried to contact behind a NAT
374 struct GNUNET_CONTAINER_MultiHashMap *nat_wait_conns;
377 * The external address given to us by the user. Must be actual
378 * outside visible address for NAT punching to work.
380 char *external_address;
383 * The internal address given to us by the user (or discovered).
385 char *internal_address;
388 * List of our IP addresses.
390 struct LocalAddrList *lal_head;
393 * Tail of our IP address list.
395 struct LocalAddrList *lal_tail;
398 * ID of task used to update our addresses when one expires.
400 GNUNET_SCHEDULER_TaskIdentifier address_update_task;
403 * Port that we are actually listening on.
408 * Port that the user said we would have visible to the
414 * Is this transport configured to be behind a NAT?
419 * Is this transport configured to allow connections to NAT'd peers?
424 * Should this transport advertise only NAT addresses (port set to 0)?
425 * If not, all addresses will be duplicated for NAT punching and regular
428 int only_nat_addresses;
434 add_to_address_list (struct Plugin *plugin,
438 struct LocalAddrList *lal;
440 lal = plugin->lal_head;
443 if ( (lal->size == arg_size) &&
444 (0 == memcmp (&lal[1], arg, arg_size)) )
448 lal = GNUNET_malloc (sizeof (struct LocalAddrList) + arg_size);
449 lal->size = arg_size;
450 memcpy (&lal[1], arg, arg_size);
451 GNUNET_CONTAINER_DLL_insert (plugin->lal_head,
458 check_local_addr (struct Plugin *plugin,
462 struct LocalAddrList *lal;
464 lal = plugin->lal_head;
467 if ( (lal->size == arg_size) &&
468 (0 == memcmp (&lal[1], arg, arg_size)) )
472 return GNUNET_SYSERR;
477 * Function called for a quick conversion of the binary address to
478 * a numeric address. Note that the caller must not free the
479 * address and that the next call to this function is allowed
480 * to override the address again.
482 * @param cls closure ('struct Plugin*')
483 * @param addr binary address
484 * @param addrlen length of the address
485 * @return string representing the same address
488 tcp_address_to_string (void *cls,
492 static char rbuf[INET6_ADDRSTRLEN + 12];
493 char buf[INET6_ADDRSTRLEN];
497 const struct IPv4TcpAddress *t4;
498 const struct IPv6TcpAddress *t6;
502 if (addrlen == sizeof (struct IPv6TcpAddress))
506 port = ntohs (t6->t6_port);
507 memcpy (&a6, &t6->ipv6_addr, sizeof (a6));
510 else if (addrlen == sizeof (struct IPv4TcpAddress))
514 port = ntohs (t4->t_port);
515 memcpy (&a4, &t4->ipv4_addr, sizeof (a4));
520 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
522 _("Unexpected address length: %u\n"),
527 if (NULL == inet_ntop (af, sb, buf, INET6_ADDRSTRLEN))
529 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
532 GNUNET_snprintf (rbuf,
534 (af == AF_INET6) ? "[%s]:%u" : "%s:%u",
542 * Find the session handle for the given client.
544 * @return NULL if no matching session exists
546 static struct Session *
547 find_session_by_client (struct Plugin *plugin,
548 const struct GNUNET_SERVER_Client *client)
552 ret = plugin->sessions;
553 while ((ret != NULL) && (client != ret->client))
559 * Create a new session. Also queues a welcome message.
562 * @param target peer to connect to
563 * @param client client to use
564 * @param is_nat this a NAT session, we should wait for a client to
565 * connect to us from an address, then assign that to
567 * @return new session object
569 static struct Session *
570 create_session (struct Plugin *plugin,
571 const struct GNUNET_PeerIdentity *target,
572 struct GNUNET_SERVER_Client *client, int is_nat)
575 struct PendingMessage *pm;
576 struct WelcomeMessage welcome;
578 if (is_nat != GNUNET_YES)
579 GNUNET_assert (client != NULL);
581 GNUNET_assert (client == NULL);
584 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
586 "Creating new session for peer `%4s'\n",
587 GNUNET_i2s (target));
589 ret = GNUNET_malloc (sizeof (struct Session));
590 ret->last_activity = GNUNET_TIME_absolute_get ();
591 ret->plugin = plugin;
592 if (is_nat != GNUNET_YES) /* If not a NAT WAIT conn, add it to global list */
594 ret->next = plugin->sessions;
595 plugin->sessions = ret;
597 ret->client = client;
598 ret->target = *target;
599 ret->expecting_welcome = GNUNET_YES;
600 pm = GNUNET_malloc (sizeof (struct PendingMessage) + sizeof (struct WelcomeMessage));
601 pm->msg = (const char*) &pm[1];
602 pm->message_size = sizeof (struct WelcomeMessage);
603 welcome.header.size = htons (sizeof (struct WelcomeMessage));
604 welcome.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME);
605 welcome.clientIdentity = *plugin->env->my_identity;
606 memcpy (&pm[1], &welcome, sizeof (welcome));
607 pm->timeout = GNUNET_TIME_UNIT_FOREVER_ABS;
608 GNUNET_STATISTICS_update (plugin->env->stats,
609 gettext_noop ("# bytes currently in TCP buffers"),
612 GNUNET_CONTAINER_DLL_insert (ret->pending_messages_head,
613 ret->pending_messages_tail,
615 if (is_nat != GNUNET_YES)
616 GNUNET_STATISTICS_update (plugin->env->stats,
617 gettext_noop ("# TCP sessions active"),
625 * If we have pending messages, ask the server to
626 * transmit them (schedule the respective tasks, etc.)
628 * @param session for which session should we do this
630 static void process_pending_messages (struct Session *session);
634 * Function called to notify a client about the socket
635 * being ready to queue more data. "buf" will be
636 * NULL and "size" zero if the socket was closed for
637 * writing in the meantime.
640 * @param size number of bytes available in buf
641 * @param buf where the callee should write the message
642 * @return number of bytes written to buf
645 do_transmit (void *cls, size_t size, void *buf)
647 struct Session *session = cls;
648 struct GNUNET_PeerIdentity pid;
649 struct Plugin *plugin;
650 struct PendingMessage *pos;
651 struct PendingMessage *hd;
652 struct PendingMessage *tl;
653 struct GNUNET_TIME_Absolute now;
657 session->transmit_handle = NULL;
658 plugin = session->plugin;
662 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
664 "Timeout trying to transmit to peer `%4s', discarding message queue.\n",
665 GNUNET_i2s (&session->target));
667 /* timeout; cancel all messages that have already expired */
671 now = GNUNET_TIME_absolute_get ();
672 while ( (NULL != (pos = session->pending_messages_head)) &&
673 (pos->timeout.value <= now.value) )
675 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
676 session->pending_messages_tail,
679 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
681 "Failed to transmit %u byte message to `%4s'.\n",
683 GNUNET_i2s (&session->target));
685 ret += pos->message_size;
686 GNUNET_CONTAINER_DLL_insert_after (hd, tl, tl, pos);
688 /* do this call before callbacks (so that if callbacks destroy
689 session, they have a chance to cancel actions done by this
691 process_pending_messages (session);
692 pid = session->target;
693 /* no do callbacks and do not use session again since
694 the callbacks may abort the session */
695 while (NULL != (pos = hd))
697 GNUNET_CONTAINER_DLL_remove (hd, tl, pos);
698 if (pos->transmit_cont != NULL)
699 pos->transmit_cont (pos->transmit_cont_cls,
700 &pid, GNUNET_SYSERR);
703 GNUNET_STATISTICS_update (plugin->env->stats,
704 gettext_noop ("# bytes currently in TCP buffers"),
707 GNUNET_STATISTICS_update (plugin->env->stats,
708 gettext_noop ("# bytes discarded by TCP (timeout)"),
713 /* copy all pending messages that would fit */
718 while (NULL != (pos = session->pending_messages_head))
720 if (ret + pos->message_size > size)
722 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
723 session->pending_messages_tail,
725 GNUNET_assert (size >= pos->message_size);
726 /* FIXME: this memcpy can be up to 7% of our total runtime */
727 memcpy (cbuf, pos->msg, pos->message_size);
728 cbuf += pos->message_size;
729 ret += pos->message_size;
730 size -= pos->message_size;
731 GNUNET_CONTAINER_DLL_insert_after (hd, tl, tl, pos);
733 /* schedule 'continuation' before callbacks so that callbacks that
734 cancel everything don't cause us to use a session that no longer
736 process_pending_messages (session);
737 session->last_activity = GNUNET_TIME_absolute_get ();
738 pid = session->target;
739 /* we'll now call callbacks that may cancel the session; hence
740 we should not use 'session' after this point */
741 while (NULL != (pos = hd))
743 GNUNET_CONTAINER_DLL_remove (hd, tl, pos);
744 if (pos->transmit_cont != NULL)
745 pos->transmit_cont (pos->transmit_cont_cls,
749 GNUNET_assert (hd == NULL);
750 GNUNET_assert (tl == NULL);
752 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
753 "tcp", "Transmitting %u bytes\n", ret);
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))
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 (session %p).\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) : "*",
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;
829 session->plugin->env->session_end (session->plugin->env->cls,
833 if (session->transmit_handle != NULL)
835 GNUNET_CONNECTION_notify_transmit_ready_cancel
836 (session->transmit_handle);
837 session->transmit_handle = NULL;
839 while (NULL != (pm = session->pending_messages_head))
842 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
844 pm->transmit_cont != NULL
845 ? "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->plugin->env->sched,
870 session->receive_delay_task);
871 if (session->client != NULL)
872 GNUNET_SERVER_receive_done (session->client,
875 if (session->client != NULL)
876 GNUNET_SERVER_client_drop (session->client);
877 GNUNET_STATISTICS_update (session->plugin->env->stats,
878 gettext_noop ("# TCP sessions active"),
881 GNUNET_free_non_null (session->connect_addr);
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.value < s2->last_activity.value)
909 if (s1->last_activity.value > s2->last_activity.value)
911 if ( (GNUNET_YES == s1->inbound) &&
912 (GNUNET_NO == s2->inbound) )
914 if ( (GNUNET_NO == s1->inbound) &&
915 (GNUNET_YES == s2->inbound) )
922 * We learned about a peer (possibly behind NAT) so run the
923 * gnunet-nat-client to send dummy ICMP responses
925 * @param plugin the plugin for this transport
926 * @param addr the address of the peer
927 * @param addrlen the length of the address
930 run_gnunet_nat_client (struct Plugin *plugin, const char *addr, size_t addrlen)
932 char inet4[INET_ADDRSTRLEN];
933 char *address_as_string;
934 char *port_as_string;
936 const struct sockaddr *sa = (const struct sockaddr *)addr;
938 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "tcp",
939 _("called run_gnunet_nat_client addrlen %d others are %d and %d\n"), addrlen, sizeof (struct sockaddr), sizeof (struct sockaddr_in));
942 if (addrlen < sizeof (struct sockaddr))
945 switch (sa->sa_family)
948 if (addrlen != sizeof (struct sockaddr_in))
950 if (NULL == inet_ntop (AF_INET,
951 &((struct sockaddr_in *) sa)->sin_addr,
952 inet4, INET_ADDRSTRLEN))
954 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
957 address_as_string = GNUNET_strdup (inet4);
964 GNUNET_asprintf(&port_as_string, "%d", plugin->adv_port);
966 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "tcp",
967 _("Running gnunet-nat-client with arguments: %s %s %d\n"), plugin->external_address, address_as_string, plugin->adv_port);
970 /* Start the client process */
971 pid = GNUNET_OS_start_process(NULL, NULL, "gnunet-nat-client", "gnunet-nat-client", plugin->external_address, address_as_string, port_as_string, NULL);
972 GNUNET_free(address_as_string);
973 GNUNET_free(port_as_string);
974 GNUNET_OS_process_wait (pid);
979 * Function that can be used by the transport service to transmit
980 * a message using the plugin. Note that in the case of a
981 * peer disconnecting, the continuation MUST be called
982 * prior to the disconnect notification itself. This function
983 * will be called with this peer's HELLO message to initiate
984 * a fresh connection to another peer.
987 * @param target who should receive this message
988 * @param msg the message to transmit
989 * @param msgbuf_size number of bytes in 'msg'
990 * @param priority how important is the message (most plugins will
991 * ignore message priority and just FIFO)
992 * @param timeout how long to wait at most for the transmission (does not
993 * require plugins to discard the message after the timeout,
994 * just advisory for the desired delay; most plugins will ignore
996 * @param session which session must be used (or NULL for "any")
997 * @param addr the address to use (can be NULL if the plugin
998 * is "on its own" (i.e. re-use existing TCP connection))
999 * @param addrlen length of the address in bytes
1000 * @param force_address GNUNET_YES if the plugin MUST use the given address,
1001 * GNUNET_NO means the plugin may use any other address and
1002 * GNUNET_SYSERR means that only reliable existing
1003 * bi-directional connections should be used (regardless
1005 * @param cont continuation to call once the message has
1006 * been transmitted (or if the transport is ready
1007 * for the next transmission call; or if the
1008 * peer disconnected...); can be NULL
1009 * @param cont_cls closure for cont
1010 * @return number of bytes used (on the physical network, with overheads);
1011 * -1 on hard errors (i.e. address invalid); 0 is a legal value
1012 * and does NOT mean that the message was not transmitted (DV and NAT)
1015 tcp_plugin_send (void *cls,
1016 const struct GNUNET_PeerIdentity *target,
1020 struct GNUNET_TIME_Relative timeout,
1021 struct Session *session,
1025 GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
1027 struct Plugin *plugin = cls;
1028 struct Session *cand_session;
1029 struct Session *next;
1030 struct PendingMessage *pm;
1031 struct GNUNET_CONNECTION_Handle *sa;
1035 struct sockaddr_in a4;
1036 struct sockaddr_in6 a6;
1037 const struct IPv4TcpAddress *t4;
1038 const struct IPv6TcpAddress *t6;
1039 unsigned int is_natd;
1041 GNUNET_STATISTICS_update (plugin->env->stats,
1042 gettext_noop ("# bytes TCP was asked to transmit"),
1045 /* FIXME: we could do this cheaper with a hash table
1046 where we could restrict the iteration to entries that match
1047 the target peer... */
1048 is_natd = GNUNET_NO;
1049 if (session == NULL)
1051 cand_session = NULL;
1052 next = plugin->sessions;
1053 while (NULL != (session = next))
1055 next = session->next;
1056 GNUNET_assert (session->client != NULL);
1057 if (0 != memcmp (target,
1059 sizeof (struct GNUNET_PeerIdentity)))
1061 if ( ( (GNUNET_SYSERR == force_address) &&
1062 (session->expecting_welcome == GNUNET_NO) ) ||
1063 (GNUNET_NO == force_address) )
1065 cand_session = select_better_session (cand_session,
1069 if (GNUNET_SYSERR == force_address)
1071 GNUNET_break (GNUNET_YES == force_address);
1077 if (session->inbound == GNUNET_YES)
1079 if (addrlen != session->connect_alen)
1081 if (0 != memcmp (session->connect_addr,
1085 cand_session = select_better_session (cand_session,
1088 session = cand_session;
1090 if ( (session == NULL) &&
1094 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1096 "Asked to transmit to `%4s' without address and I have no existing connection (failing).\n",
1097 GNUNET_i2s (target));
1099 GNUNET_STATISTICS_update (plugin->env->stats,
1100 gettext_noop ("# bytes discarded by TCP (no address and no connection)"),
1105 if (session == NULL)
1107 if (addrlen == sizeof (struct IPv6TcpAddress))
1111 memset (&a6, 0, sizeof (a6));
1112 #if HAVE_SOCKADDR_IN_SIN_LEN
1113 a6.sin6_len = sizeof (a6);
1115 a6.sin6_family = AF_INET6;
1116 a6.sin6_port = t6->t6_port;
1117 if (t6->t6_port == 0)
1118 is_natd = GNUNET_YES;
1119 memcpy (&a6.sin6_addr,
1121 sizeof (struct in6_addr));
1125 else if (addrlen == sizeof (struct IPv4TcpAddress))
1129 memset (&a4, 0, sizeof (a4));
1130 #if HAVE_SOCKADDR_IN_SIN_LEN
1131 a4.sin_len = sizeof (a4);
1133 a4.sin_family = AF_INET;
1134 a4.sin_port = t4->t_port;
1135 if (t4->t_port == 0)
1136 is_natd = GNUNET_YES;
1137 a4.sin_addr.s_addr = t4->ipv4_addr;
1143 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
1145 _("Address of unexpected length: %u\n"),
1151 if ((is_natd == GNUNET_YES) && (addrlen == sizeof (struct IPv6TcpAddress)))
1152 return -1; /* NAT client only works with IPv4 addresses */
1155 if ( (plugin->allow_nat == GNUNET_YES) && (is_natd == GNUNET_YES) &&
1156 (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns, &target->hashPubKey)))
1159 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1161 _("Found valid IPv4 NAT address!\n"));
1163 session = create_session (plugin,
1167 /* create new message entry */
1168 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msgbuf_size);
1169 /* FIXME: the memset of this malloc can be up to 2% of our total runtime */
1170 pm->msg = (const char*) &pm[1];
1171 memcpy (&pm[1], msg, msgbuf_size);
1172 /* FIXME: this memcpy can be up to 7% of our total run-time
1173 (for transport service) */
1174 pm->message_size = msgbuf_size;
1175 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1176 pm->transmit_cont = cont;
1177 pm->transmit_cont_cls = cont_cls;
1179 /* append pm to pending_messages list */
1180 GNUNET_CONTAINER_DLL_insert_after (session->pending_messages_head,
1181 session->pending_messages_tail,
1182 session->pending_messages_tail,
1185 GNUNET_assert(GNUNET_CONTAINER_multihashmap_put(plugin->nat_wait_conns, &target->hashPubKey, session, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY) == GNUNET_OK);
1187 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1189 "Created NAT WAIT connection to `%4s' at `%s'\n",
1190 GNUNET_i2s (target),
1191 GNUNET_a2s (sb, sbs));
1193 run_gnunet_nat_client(plugin, sb, sbs);
1196 else if ((plugin->allow_nat == GNUNET_YES) && (is_natd == GNUNET_YES) && (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns, &target->hashPubKey)))
1198 /* Only do one NAT punch attempt per peer identity */
1201 sa = GNUNET_CONNECTION_create_from_sockaddr (plugin->env->sched,
1203 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1);
1207 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1209 "Failed to create connection to `%4s' at `%s'\n",
1210 GNUNET_i2s (target),
1211 GNUNET_a2s (sb, sbs));
1213 GNUNET_STATISTICS_update (plugin->env->stats,
1214 gettext_noop ("# bytes discarded by TCP (failed to connect)"),
1220 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1222 "Asked to transmit to `%4s', creating fresh session using address `%s'.\n",
1223 GNUNET_i2s (target),
1224 GNUNET_a2s (sb, sbs));
1226 session = create_session (plugin,
1228 GNUNET_SERVER_connect_socket (plugin->server,
1230 session->connect_addr = GNUNET_malloc (addrlen);
1231 memcpy (session->connect_addr,
1234 session->connect_alen = addrlen;
1236 GNUNET_assert (session != NULL);
1237 GNUNET_assert (session->client != NULL);
1238 GNUNET_STATISTICS_update (plugin->env->stats,
1239 gettext_noop ("# bytes currently in TCP buffers"),
1242 /* create new message entry */
1243 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msgbuf_size);
1244 pm->msg = (const char*) &pm[1];
1245 memcpy (&pm[1], msg, msgbuf_size);
1246 pm->message_size = msgbuf_size;
1247 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1248 pm->transmit_cont = cont;
1249 pm->transmit_cont_cls = cont_cls;
1251 /* append pm to pending_messages list */
1252 GNUNET_CONTAINER_DLL_insert_after (session->pending_messages_head,
1253 session->pending_messages_tail,
1254 session->pending_messages_tail,
1257 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1259 "Asked to transmit %u bytes to `%s', added message to list.\n",
1261 GNUNET_i2s (target));
1263 process_pending_messages (session);
1269 * Function that can be called to force a disconnect from the
1270 * specified neighbour. This should also cancel all previously
1271 * scheduled transmissions. Obviously the transmission may have been
1272 * partially completed already, which is OK. The plugin is supposed
1273 * to close the connection (if applicable) and no longer call the
1274 * transmit continuation(s).
1276 * Finally, plugin MUST NOT call the services's receive function to
1277 * notify the service that the connection to the specified target was
1278 * closed after a getting this call.
1280 * @param cls closure
1281 * @param target peer for which the last transmission is
1285 tcp_plugin_disconnect (void *cls,
1286 const struct GNUNET_PeerIdentity *target)
1288 struct Plugin *plugin = cls;
1289 struct Session *session;
1290 struct Session *next;
1291 struct PendingMessage *pm;
1294 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1296 "Asked to cancel session with `%4s'\n",
1297 GNUNET_i2s (target));
1299 next = plugin->sessions;
1300 while (NULL != (session = next))
1302 next = session->next;
1303 if (0 != memcmp (target,
1305 sizeof (struct GNUNET_PeerIdentity)))
1307 pm = session->pending_messages_head;
1310 pm->transmit_cont = NULL;
1311 pm->transmit_cont_cls = NULL;
1314 disconnect_session (session);
1320 * Context for address to string conversion.
1322 struct PrettyPrinterContext
1325 * Function to call with the result.
1327 GNUNET_TRANSPORT_AddressStringCallback asc;
1330 * Clsoure for 'asc'.
1335 * Port to add after the IP address.
1342 * Append our port and forward the result.
1344 * @param cls the 'struct PrettyPrinterContext*'
1345 * @param hostname hostname part of the address
1348 append_port (void *cls, const char *hostname)
1350 struct PrettyPrinterContext *ppc = cls;
1353 if (hostname == NULL)
1355 ppc->asc (ppc->asc_cls, NULL);
1359 GNUNET_asprintf (&ret, "%s:%d", hostname, ppc->port);
1360 ppc->asc (ppc->asc_cls, ret);
1366 * Convert the transports address to a nice, human-readable
1369 * @param cls closure
1370 * @param type name of the transport that generated the address
1371 * @param addr one of the addresses of the host, NULL for the last address
1372 * the specific address format depends on the transport
1373 * @param addrlen length of the address
1374 * @param numeric should (IP) addresses be displayed in numeric form?
1375 * @param timeout after how long should we give up?
1376 * @param asc function to call on each string
1377 * @param asc_cls closure for asc
1380 tcp_plugin_address_pretty_printer (void *cls,
1385 struct GNUNET_TIME_Relative timeout,
1386 GNUNET_TRANSPORT_AddressStringCallback asc,
1389 struct Plugin *plugin = cls;
1390 struct PrettyPrinterContext *ppc;
1393 struct sockaddr_in a4;
1394 struct sockaddr_in6 a6;
1395 const struct IPv4TcpAddress *t4;
1396 const struct IPv6TcpAddress *t6;
1399 if (addrlen == sizeof (struct IPv6TcpAddress))
1402 memset (&a6, 0, sizeof (a6));
1403 a6.sin6_family = AF_INET6;
1404 a6.sin6_port = t6->t6_port;
1405 memcpy (&a6.sin6_addr,
1407 sizeof (struct in6_addr));
1408 port = ntohs (t6->t6_port);
1412 else if (addrlen == sizeof (struct IPv4TcpAddress))
1415 memset (&a4, 0, sizeof (a4));
1416 a4.sin_family = AF_INET;
1417 a4.sin_port = t4->t_port;
1418 a4.sin_addr.s_addr = t4->ipv4_addr;
1419 port = ntohs (t4->t_port);
1425 /* invalid address */
1426 GNUNET_break_op (0);
1427 asc (asc_cls, NULL);
1430 ppc = GNUNET_malloc (sizeof (struct PrettyPrinterContext));
1432 ppc->asc_cls = asc_cls;
1434 GNUNET_RESOLVER_hostname_get (plugin->env->sched,
1438 !numeric, timeout, &append_port, ppc);
1443 * Check if the given port is plausible (must be either
1444 * our listen port or our advertised port). If it is
1445 * neither, we return GNUNET_SYSERR.
1447 * @param plugin global variables
1448 * @param in_port port number to check
1449 * @return GNUNET_OK if port is either open_port or adv_port
1452 check_port (struct Plugin *plugin, uint16_t in_port)
1454 if ( (plugin->behind_nat == GNUNET_YES) && (in_port == 0) )
1456 if ( (plugin->only_nat_addresses == GNUNET_YES) &&
1457 (plugin->behind_nat == GNUNET_YES) &&
1460 return GNUNET_SYSERR; /* odd case... */
1462 if ((in_port == plugin->adv_port) || (in_port == plugin->open_port))
1464 return GNUNET_SYSERR;
1469 * Function that will be called to check if a binary address for this
1470 * plugin is well-formed and corresponds to an address for THIS peer
1471 * (as per our configuration). Naturally, if absolutely necessary,
1472 * plugins can be a bit conservative in their answer, but in general
1473 * plugins should make sure that the address does not redirect
1474 * traffic to a 3rd party that might try to man-in-the-middle our
1477 * @param cls closure, our 'struct Plugin*'
1478 * @param addr pointer to the address
1479 * @param addrlen length of addr
1480 * @return GNUNET_OK if this is a plausible address for this peer
1481 * and transport, GNUNET_SYSERR if not
1484 tcp_plugin_check_address (void *cls,
1488 struct Plugin *plugin = cls;
1489 struct IPv4TcpAddress *v4;
1490 struct IPv6TcpAddress *v6;
1492 if ((addrlen != sizeof (struct IPv4TcpAddress)) &&
1493 (addrlen != sizeof (struct IPv6TcpAddress)))
1495 GNUNET_break_op (0);
1496 return GNUNET_SYSERR;
1498 if (addrlen == sizeof (struct IPv4TcpAddress))
1500 v4 = (struct IPv4TcpAddress *) addr;
1502 check_port (plugin, ntohs (v4->t_port)))
1503 return GNUNET_SYSERR;
1505 check_local_addr (plugin, &v4->ipv4_addr, sizeof (uint32_t)))
1507 return GNUNET_SYSERR;
1512 v6 = (struct IPv6TcpAddress *) addr;
1513 if (IN6_IS_ADDR_LINKLOCAL (&v6->ipv6_addr))
1515 GNUNET_break_op (0);
1516 return GNUNET_SYSERR;
1519 check_port (plugin, ntohs (v6->t6_port)))
1520 return GNUNET_SYSERR;
1522 check_local_addr (plugin, &v6->ipv6_addr, sizeof (struct in6_addr)))
1524 return GNUNET_SYSERR;
1531 * We've received a nat probe from this peer via TCP. Finish
1532 * creating the client session and resume sending of queued
1535 * @param cls closure
1536 * @param client identification of the client
1537 * @param message the actual message
1540 handle_tcp_nat_probe (void *cls,
1541 struct GNUNET_SERVER_Client *client,
1542 const struct GNUNET_MessageHeader *message)
1544 struct Plugin *plugin = cls;
1545 struct Session *session;
1546 struct TCP_NAT_ProbeMessage *tcp_nat_probe;
1549 struct IPv4TcpAddress *t4;
1550 struct IPv6TcpAddress *t6;
1551 const struct sockaddr_in *s4;
1552 const struct sockaddr_in6 *s6;
1555 GNUNET_log_from(GNUNET_ERROR_TYPE_DEBUG, "tcp", "received tcp NAT probe\n");
1557 /* We have received a TCP NAT probe, meaning we (hopefully) initiated
1558 * a connection to this peer by running gnunet-nat-client. This peer
1559 * received the punch message and now wants us to use the new connection
1560 * as the default for that peer. Do so and then send a WELCOME message
1561 * so we can really be connected!
1563 if (ntohs(message->size) != sizeof(struct TCP_NAT_ProbeMessage))
1566 GNUNET_log_from(GNUNET_ERROR_TYPE_DEBUG, "tcp", "Bad size fo tcp NAT probe, expected %d got %d.\n", sizeof(struct TCP_NAT_ProbeMessage), ntohs(message->size));
1571 tcp_nat_probe = (struct TCP_NAT_ProbeMessage *)message;
1573 if (GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns, &tcp_nat_probe->clientIdentity.hashPubKey) == GNUNET_YES)
1576 GNUNET_log_from(GNUNET_ERROR_TYPE_DEBUG, "tcp", "Found session for NAT probe!\n");
1578 session = GNUNET_CONTAINER_multihashmap_get(plugin->nat_wait_conns, &tcp_nat_probe->clientIdentity.hashPubKey);
1579 GNUNET_assert(session != NULL);
1580 GNUNET_assert(GNUNET_CONTAINER_multihashmap_remove(plugin->nat_wait_conns, &tcp_nat_probe->clientIdentity.hashPubKey, session) == GNUNET_YES);
1581 GNUNET_SERVER_client_keep (client);
1582 session->client = client;
1583 session->last_activity = GNUNET_TIME_absolute_get ();
1586 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1589 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1591 "Found address `%s' for incoming connection %p\n",
1592 GNUNET_a2s (vaddr, alen),
1595 if (alen == sizeof (struct sockaddr_in))
1598 t4 = GNUNET_malloc (sizeof (struct IPv4TcpAddress));
1599 t4->t_port = s4->sin_port;
1600 t4->ipv4_addr = s4->sin_addr.s_addr;
1601 session->connect_addr = t4;
1602 session->connect_alen = sizeof (struct IPv4TcpAddress);
1604 else if (alen == sizeof (struct sockaddr_in6))
1607 t6 = GNUNET_malloc (sizeof (struct IPv6TcpAddress));
1608 t6->t6_port = s6->sin6_port;
1609 memcpy (&t6->ipv6_addr,
1611 sizeof (struct in6_addr));
1612 session->connect_addr = t6;
1613 session->connect_alen = sizeof (struct IPv6TcpAddress);
1616 session->connect_addr = GNUNET_malloc (alen);
1617 memcpy (session->connect_addr,
1620 session->connect_alen = alen;
1621 GNUNET_free (vaddr);
1624 session->next = plugin->sessions;
1625 plugin->sessions = session;
1626 GNUNET_STATISTICS_update (plugin->env->stats,
1627 gettext_noop ("# TCP sessions active"),
1630 process_pending_messages (session);
1635 GNUNET_log_from(GNUNET_ERROR_TYPE_DEBUG, "tcp", "Did NOT find session for NAT probe!\n");
1641 * We've received a welcome from this peer via TCP. Possibly create a
1642 * fresh client record and send back our welcome.
1644 * @param cls closure
1645 * @param client identification of the client
1646 * @param message the actual message
1649 handle_tcp_welcome (void *cls,
1650 struct GNUNET_SERVER_Client *client,
1651 const struct GNUNET_MessageHeader *message)
1653 struct Plugin *plugin = cls;
1654 const struct WelcomeMessage *wm = (const struct WelcomeMessage *) message;
1655 struct Session *session;
1658 struct IPv4TcpAddress *t4;
1659 struct IPv6TcpAddress *t6;
1660 const struct sockaddr_in *s4;
1661 const struct sockaddr_in6 *s6;
1665 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1667 "Received %s message from a `%4s/%p'.\n",
1669 GNUNET_i2s (&wm->clientIdentity), client);
1671 GNUNET_STATISTICS_update (plugin->env->stats,
1672 gettext_noop ("# TCP WELCOME messages received"),
1675 session = find_session_by_client (plugin, client);
1676 if (session == NULL)
1678 GNUNET_SERVER_client_keep (client);
1679 session = create_session (plugin,
1680 &wm->clientIdentity, client, GNUNET_NO);
1681 session->inbound = GNUNET_YES;
1683 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1686 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1688 "Found address `%s' for incoming connection %p\n",
1689 GNUNET_a2s (vaddr, alen),
1692 if (alen == sizeof (struct sockaddr_in))
1695 t4 = GNUNET_malloc (sizeof (struct IPv4TcpAddress));
1696 t4->t_port = s4->sin_port;
1697 t4->ipv4_addr = s4->sin_addr.s_addr;
1698 session->connect_addr = t4;
1699 session->connect_alen = sizeof (struct IPv4TcpAddress);
1701 else if (alen == sizeof (struct sockaddr_in6))
1704 t6 = GNUNET_malloc (sizeof (struct IPv6TcpAddress));
1705 t6->t6_port = s6->sin6_port;
1706 memcpy (&t6->ipv6_addr,
1708 sizeof (struct in6_addr));
1709 session->connect_addr = t6;
1710 session->connect_alen = sizeof (struct IPv6TcpAddress);
1712 GNUNET_free (vaddr);
1717 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1719 "Did not obtain TCP socket address for incoming connection\n");
1723 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1725 "Creating new session %p for connection %p\n",
1728 process_pending_messages (session);
1730 if (session->expecting_welcome != GNUNET_YES)
1732 GNUNET_break_op (0);
1733 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1736 session->last_activity = GNUNET_TIME_absolute_get ();
1737 session->expecting_welcome = GNUNET_NO;
1738 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1743 * Task to signal the server that we can continue
1744 * receiving from the TCP client now.
1746 * @param cls the 'struct Session*'
1747 * @param tc task context (unused)
1750 delayed_done (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1752 struct Session *session = cls;
1753 struct GNUNET_TIME_Relative delay;
1755 session->receive_delay_task = GNUNET_SCHEDULER_NO_TASK;
1756 delay = session->plugin->env->receive (session->plugin->env->cls,
1761 if (delay.value == 0)
1762 GNUNET_SERVER_receive_done (session->client, GNUNET_OK);
1764 session->receive_delay_task =
1765 GNUNET_SCHEDULER_add_delayed (session->plugin->env->sched,
1766 delay, &delayed_done, session);
1771 * We've received data for this peer via TCP. Unbox,
1772 * compute latency and forward.
1774 * @param cls closure
1775 * @param client identification of the client
1776 * @param message the actual message
1779 handle_tcp_data (void *cls,
1780 struct GNUNET_SERVER_Client *client,
1781 const struct GNUNET_MessageHeader *message)
1783 struct Plugin *plugin = cls;
1784 struct Session *session;
1785 struct GNUNET_TIME_Relative delay;
1787 if ((GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME == ntohs(message->type)) || (ntohs(message->type) == GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE))
1789 /* We don't want to propagate WELCOME and NAT Probe messages up! */
1790 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1793 session = find_session_by_client (plugin, client);
1794 if ( (NULL == session) || (GNUNET_YES == session->expecting_welcome))
1796 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1799 session->last_activity = GNUNET_TIME_absolute_get ();
1801 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1803 "Passing %u bytes of type %u from `%4s' to transport service.\n",
1804 (unsigned int) ntohs (message->size),
1805 (unsigned int) ntohs (message->type),
1806 GNUNET_i2s (&session->target));
1808 GNUNET_STATISTICS_update (plugin->env->stats,
1809 gettext_noop ("# bytes received via TCP"),
1810 ntohs (message->size),
1812 delay = plugin->env->receive (plugin->env->cls, &session->target, message, 1,
1814 (GNUNET_YES == session->inbound) ? NULL : session->connect_addr,
1815 (GNUNET_YES == session->inbound) ? 0 : session->connect_alen);
1816 if (delay.value == 0)
1817 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1819 session->receive_delay_task =
1820 GNUNET_SCHEDULER_add_delayed (session->plugin->env->sched,
1821 delay, &delayed_done, session);
1826 * Functions with this signature are called whenever a peer
1827 * is disconnected on the network level.
1829 * @param cls closure
1830 * @param client identification of the client
1833 disconnect_notify (void *cls,
1834 struct GNUNET_SERVER_Client *client)
1836 struct Plugin *plugin = cls;
1837 struct Session *session;
1841 session = find_session_by_client (plugin, client);
1842 if (session == NULL)
1843 return; /* unknown, nothing to do */
1845 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1847 "Destroying session of `%4s' with %s (%p) due to network-level disconnect.\n",
1848 GNUNET_i2s (&session->target),
1849 (session->connect_addr != NULL) ?
1850 tcp_address_to_string (session->plugin,
1851 session->connect_addr,
1852 session->connect_alen) : "*",
1855 disconnect_session (session);
1860 * Add the IP of our network interface to the list of
1861 * our external IP addresses.
1863 * @param cls the 'struct Plugin*'
1864 * @param name name of the interface
1865 * @param isDefault do we think this may be our default interface
1866 * @param addr address of the interface
1867 * @param addrlen number of bytes in addr
1868 * @return GNUNET_OK to continue iterating
1871 process_interfaces (void *cls,
1874 const struct sockaddr *addr, socklen_t addrlen)
1876 struct Plugin *plugin = cls;
1878 struct IPv4TcpAddress t4;
1879 struct IPv6TcpAddress t6;
1880 struct IPv4TcpAddress t4_nat;
1881 struct IPv6TcpAddress t6_nat;
1886 af = addr->sa_family;
1890 t4.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
1891 add_to_address_list (plugin, &t4.ipv4_addr, sizeof (uint32_t));
1892 if ((plugin->behind_nat == GNUNET_YES) && (plugin->only_nat_addresses == GNUNET_YES))
1893 t4.t_port = htons(0);
1894 else if (plugin->behind_nat == GNUNET_YES) /* We are behind NAT, but will advertise NAT and normal addresses */
1896 t4_nat.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
1897 t4_nat.t_port = htons(plugin->adv_port);
1901 t4.t_port = htons (plugin->adv_port);
1905 else if (af == AF_INET6)
1907 if (IN6_IS_ADDR_LINKLOCAL (&((struct sockaddr_in6 *) addr)->sin6_addr))
1909 /* skip link local addresses */
1912 memcpy (&t6.ipv6_addr,
1913 &((struct sockaddr_in6 *) addr)->sin6_addr,
1914 sizeof (struct in6_addr));
1915 add_to_address_list (plugin, &t6.ipv6_addr, sizeof (struct in6_addr));
1916 if ((plugin->behind_nat == GNUNET_YES) && (plugin->only_nat_addresses == GNUNET_YES))
1917 t6.t6_port = htons(0);
1918 else if (plugin->behind_nat == GNUNET_YES) /* We are behind NAT, but will advertise NAT and normal addresses */
1920 memcpy (&t6_nat.ipv6_addr,
1921 &((struct sockaddr_in6 *) addr)->sin6_addr,
1922 sizeof (struct in6_addr));
1923 t6_nat.t6_port = htons(plugin->adv_port);
1927 t6.t6_port = htons (plugin->adv_port);
1936 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO |
1937 GNUNET_ERROR_TYPE_BULK,
1939 _("Found address `%s' (%s)\n"),
1940 GNUNET_a2s (addr, addrlen), name);
1942 plugin->env->notify_address (plugin->env->cls,
1944 arg, args, GNUNET_TIME_UNIT_FOREVER_REL);
1946 if (arg_nat != NULL)
1948 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO |
1949 GNUNET_ERROR_TYPE_BULK,
1951 _("Found address `%s' (%s)\n"),
1952 GNUNET_a2s (addr, addrlen), name);
1953 plugin->env->notify_address (plugin->env->cls,
1955 arg_nat, args, GNUNET_TIME_UNIT_FOREVER_REL);
1963 * Function called by the resolver for each address obtained from DNS
1964 * for our own hostname. Add the addresses to the list of our
1965 * external IP addresses.
1967 * @param cls closure
1968 * @param addr one of the addresses of the host, NULL for the last address
1969 * @param addrlen length of the address
1972 process_hostname_ips (void *cls,
1973 const struct sockaddr *addr, socklen_t addrlen)
1975 struct Plugin *plugin = cls;
1979 plugin->hostname_dns = NULL;
1982 /* FIXME: Can we figure out our external address here so it doesn't need to be user specified? */
1983 process_interfaces (plugin, "<hostname>", GNUNET_YES, addr, addrlen);
1987 * We can now send a probe message, copy into buffer to really send.
1989 * @param cls closure, a struct TCPProbeContext
1990 * @param size max size to copy
1991 * @param buf buffer to copy message to
1993 static size_t notify_send_probe (void *cls,
1994 size_t size, void *buf)
1996 struct TCPProbeContext *tcp_probe_ctx = cls;
2003 GNUNET_assert(size >= sizeof(tcp_probe_ctx->message));
2004 memcpy(buf, &tcp_probe_ctx->message, sizeof(tcp_probe_ctx->message));
2005 GNUNET_SERVER_connect_socket (tcp_probe_ctx->plugin->server,
2006 tcp_probe_ctx->sock);
2008 GNUNET_free(tcp_probe_ctx);
2009 return sizeof(tcp_probe_ctx->message);
2013 * @param cls the plugin handle
2014 * @param tc the scheduling context (for rescheduling this function again)
2016 * We have been notified that gnunet-nat-server has written something to stdout.
2017 * Handle the output, then reschedule this function to be called again once
2018 * more is available.
2022 tcp_plugin_server_read (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
2024 struct Plugin *plugin = cls;
2027 memset(&mybuf, 0, sizeof(mybuf));
2031 struct sockaddr_in in_addr;
2032 struct TCPProbeContext *tcp_probe_ctx;
2033 struct GNUNET_CONNECTION_Handle *sock;
2035 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
2038 bytes = GNUNET_DISK_file_read(plugin->server_stdout_handle, &mybuf, sizeof(mybuf));
2043 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "tcp",
2044 _("Finished reading from server stdout with code: %d\n"), bytes);
2051 for (i = 0; i < sizeof(mybuf); i++)
2053 if (mybuf[i] == '\n')
2056 if ((mybuf[i] == ':') && (i + 1 < sizeof(mybuf)))
2059 port_start = &mybuf[i + 1];
2063 if (port_start != NULL)
2064 port = atoi(port_start);
2067 plugin->server_read_task =
2068 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2069 GNUNET_TIME_UNIT_FOREVER_REL,
2070 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2075 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "tcp",
2076 _("nat-server-read read: %s port %d\n"), &mybuf, port);
2080 if (inet_pton(AF_INET, &mybuf[0], &in_addr.sin_addr) != 1)
2083 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "tcp",
2084 _("nat-server-read malformed address\n"), &mybuf, port);
2086 plugin->server_read_task =
2087 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2088 GNUNET_TIME_UNIT_FOREVER_REL,
2089 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2093 in_addr.sin_family = AF_INET;
2094 in_addr.sin_port = htons(port);
2096 * We have received an ICMP response, ostensibly from a non-NAT'd peer
2097 * that wants to connect to us! Send a message to establish a connection.
2099 sock = GNUNET_CONNECTION_create_from_sockaddr (plugin->env->sched, AF_INET, (struct sockaddr *)&in_addr,
2100 sizeof(in_addr), GNUNET_SERVER_MAX_MESSAGE_SIZE - 1);
2103 plugin->server_read_task =
2104 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2105 GNUNET_TIME_UNIT_FOREVER_REL,
2106 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2111 tcp_probe_ctx = GNUNET_malloc(sizeof(struct TCPProbeContext));
2113 tcp_probe_ctx->message.header.size = htons(sizeof(struct TCP_NAT_ProbeMessage));
2114 tcp_probe_ctx->message.header.type = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE);
2115 memcpy(&tcp_probe_ctx->message.clientIdentity, plugin->env->my_identity, sizeof(struct GNUNET_PeerIdentity));
2116 tcp_probe_ctx->plugin = plugin;
2117 tcp_probe_ctx->sock = sock;
2118 tcp_probe_ctx->transmit_handle = GNUNET_CONNECTION_notify_transmit_ready (sock,
2119 ntohs(tcp_probe_ctx->message.header.size),
2120 GNUNET_TIME_UNIT_FOREVER_REL,
2121 ¬ify_send_probe, tcp_probe_ctx);
2125 plugin->server_read_task =
2126 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2127 GNUNET_TIME_UNIT_FOREVER_REL,
2128 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2132 * Start the gnunet-nat-server process for users behind NAT.
2134 * @param plugin the transport plugin
2136 * @return GNUNET_YES if process was started, GNUNET_SYSERR on error
2139 tcp_transport_start_nat_server(struct Plugin *plugin)
2142 plugin->server_stdout = GNUNET_DISK_pipe(GNUNET_YES);
2143 if (plugin->server_stdout == NULL)
2144 return GNUNET_SYSERR;
2147 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
2149 "Starting gnunet-nat-server process cmd: %s %s\n", "gnunet-nat-server", plugin->internal_address);
2151 /* Start the server process */
2152 plugin->server_pid = GNUNET_OS_start_process(NULL, plugin->server_stdout, "gnunet-nat-server", "gnunet-nat-server", plugin->internal_address, NULL);
2153 if (plugin->server_pid == GNUNET_SYSERR)
2156 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
2158 "Failed to start gnunet-nat-server process\n");
2160 return GNUNET_SYSERR;
2162 /* Close the write end of the read pipe */
2163 GNUNET_DISK_pipe_close_end(plugin->server_stdout, GNUNET_DISK_PIPE_END_WRITE);
2165 plugin->server_stdout_handle = GNUNET_DISK_pipe_handle(plugin->server_stdout, GNUNET_DISK_PIPE_END_READ);
2166 plugin->server_read_task =
2167 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2168 GNUNET_TIME_UNIT_FOREVER_REL,
2169 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2174 * Return the actual path to a file found in the current
2175 * PATH environment variable.
2177 * @param binary the name of the file to find
2180 get_path_from_PATH (char *binary)
2188 p = getenv ("PATH");
2191 path = GNUNET_strdup (p); /* because we write on it */
2192 buf = GNUNET_malloc (strlen (path) + 20);
2195 while (NULL != (end = strchr (pos, ':')))
2198 sprintf (buf, "%s/%s", pos, binary);
2199 if (GNUNET_DISK_file_test (buf) == GNUNET_YES)
2206 sprintf (buf, "%s/%s", pos, binary);
2207 if (GNUNET_DISK_file_test (buf) == GNUNET_YES)
2218 * Check whether the suid bit is set on a file.
2219 * Attempts to find the file using the current
2220 * PATH environment variable as a search path.
2222 * @param binary the name of the file to check
2225 check_gnunet_nat_binary(char *binary)
2227 struct stat statbuf;
2230 p = get_path_from_PATH (binary);
2233 if (0 != STAT (p, &statbuf))
2236 return GNUNET_SYSERR;
2239 if ( (0 != (statbuf.st_mode & S_ISUID)) &&
2240 (statbuf.st_uid == 0) )
2246 * Entry point for the plugin.
2248 * @param cls closure, the 'struct GNUNET_TRANSPORT_PluginEnvironment*'
2249 * @return the 'struct GNUNET_TRANSPORT_PluginFunctions*' or NULL on error
2252 libgnunet_plugin_transport_tcp_init (void *cls)
2254 static const struct GNUNET_SERVER_MessageHandler my_handlers[] = {
2255 {&handle_tcp_welcome, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME,
2256 sizeof (struct WelcomeMessage)},
2257 {&handle_tcp_nat_probe, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE, sizeof (struct TCP_NAT_ProbeMessage)},
2258 {&handle_tcp_data, NULL, GNUNET_MESSAGE_TYPE_ALL, 0},
2261 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
2262 struct GNUNET_TRANSPORT_PluginFunctions *api;
2263 struct Plugin *plugin;
2264 struct GNUNET_SERVICE_Context *service;
2265 unsigned long long aport;
2266 unsigned long long bport;
2270 int only_nat_addresses;
2271 char *internal_address;
2272 char *external_address;
2273 struct sockaddr_in in_addr;
2274 struct IPv4TcpAddress t4;
2276 service = GNUNET_SERVICE_start ("transport-tcp", env->sched, env->cfg);
2277 if (service == NULL)
2279 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING,
2282 ("Failed to start service for `%s' transport plugin.\n"),
2287 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
2291 /* We are behind nat (according to the user) */
2292 if (check_gnunet_nat_binary("gnunet-nat-server") == GNUNET_YES)
2294 behind_nat = GNUNET_YES;
2298 behind_nat = GNUNET_NO;
2299 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "tcp", "Configuration specified you are behind a NAT, but gnunet-nat-server is not installed properly (suid bit not set)!\n");
2303 behind_nat = GNUNET_NO; /* We are not behind nat! */
2305 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
2309 if (check_gnunet_nat_binary("gnunet-nat-client") == GNUNET_YES)
2310 allow_nat = GNUNET_YES; /* We will try to connect to NAT'd peers */
2313 allow_nat = GNUNET_NO;
2314 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "tcp", "Configuration specified you want to connect to NAT'd peers, but gnunet-nat-client is not installed properly (suid bit not set)!\n");
2318 allow_nat = GNUNET_NO; /* We don't want to try to help NAT'd peers */
2321 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
2323 "ONLY_NAT_ADDRESSES"))
2324 only_nat_addresses = GNUNET_YES; /* We will only report our addresses as NAT'd */
2326 only_nat_addresses = GNUNET_NO; /* We will report our addresses as NAT'd and non-NAT'd */
2328 external_address = NULL;
2329 if (((GNUNET_YES == behind_nat) || (GNUNET_YES == allow_nat)) && (GNUNET_OK !=
2330 GNUNET_CONFIGURATION_get_value_string (env->cfg,
2333 &external_address)))
2335 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2338 ("Require EXTERNAL_ADDRESS for service `%s' in configuration (either BEHIND_NAT or ALLOW_NAT set to YES)!\n"),
2340 GNUNET_SERVICE_stop (service);
2344 if ((external_address != NULL) && (inet_pton(AF_INET, external_address, &in_addr.sin_addr) != 1))
2346 GNUNET_log_from(GNUNET_ERROR_TYPE_WARNING, "udp", "Malformed EXTERNAL_ADDRESS %s given in configuration!\n", external_address);
2349 internal_address = NULL;
2350 if ((GNUNET_YES == behind_nat) && (GNUNET_OK !=
2351 GNUNET_CONFIGURATION_get_value_string (env->cfg,
2354 &internal_address)))
2356 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2359 ("Require INTERNAL_ADDRESS for service `%s' in configuration!\n"),
2361 GNUNET_SERVICE_stop (service);
2362 GNUNET_free_non_null(external_address);
2366 if ((internal_address != NULL) && (inet_pton(AF_INET, internal_address, &in_addr.sin_addr) != 1))
2368 GNUNET_log_from(GNUNET_ERROR_TYPE_WARNING, "udp", "Malformed INTERNAL_ADDRESS %s given in configuration!\n", internal_address);
2373 GNUNET_CONFIGURATION_get_value_number (env->cfg,
2379 GNUNET_CONFIGURATION_get_value_number (env->cfg,
2382 &aport)) && (aport > 65535)))
2384 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2387 ("Require valid port number for service `%s' in configuration!\n"),
2389 GNUNET_free_non_null(external_address);
2390 GNUNET_free_non_null(internal_address);
2391 GNUNET_SERVICE_stop (service);
2397 plugin = GNUNET_malloc (sizeof (struct Plugin));
2398 plugin->open_port = bport;
2399 plugin->adv_port = aport;
2400 plugin->external_address = external_address;
2401 plugin->internal_address = internal_address;
2402 plugin->behind_nat = behind_nat;
2403 plugin->allow_nat = allow_nat;
2404 plugin->only_nat_addresses = only_nat_addresses;
2406 plugin->lsock = NULL;
2407 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
2409 api->send = &tcp_plugin_send;
2410 api->disconnect = &tcp_plugin_disconnect;
2411 api->address_pretty_printer = &tcp_plugin_address_pretty_printer;
2412 api->check_address = &tcp_plugin_check_address;
2413 api->address_to_string = &tcp_address_to_string;
2414 plugin->service = service;
2415 plugin->server = GNUNET_SERVICE_get_server (service);
2416 plugin->handlers = GNUNET_malloc (sizeof (my_handlers));
2417 memcpy (plugin->handlers, my_handlers, sizeof (my_handlers));
2420 sizeof (my_handlers) / sizeof (struct GNUNET_SERVER_MessageHandler);
2422 plugin->handlers[i].callback_cls = plugin;
2423 GNUNET_SERVER_add_handlers (plugin->server, plugin->handlers);
2425 if (behind_nat == GNUNET_YES)
2427 if (GNUNET_YES != tcp_transport_start_nat_server(plugin))
2429 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2432 ("Failed to start %s required for NAT in %s!\n"),
2435 GNUNET_free_non_null(external_address);
2436 GNUNET_free_non_null(internal_address);
2437 GNUNET_SERVICE_stop (service);
2442 if (allow_nat == GNUNET_YES)
2444 plugin->nat_wait_conns = GNUNET_CONTAINER_multihashmap_create(100);
2445 GNUNET_assert(plugin->nat_wait_conns != NULL);
2448 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2449 "tcp", _("TCP transport listening on port %llu\n"), bport);
2451 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2453 _("TCP transport advertises itself as being on port %llu\n"),
2455 GNUNET_SERVER_disconnect_notify (plugin->server,
2458 if (plugin->behind_nat == GNUNET_NO)
2460 GNUNET_OS_network_interfaces_list (&process_interfaces, plugin);
2463 plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (env->sched,
2466 HOSTNAME_RESOLVE_TIMEOUT,
2467 &process_hostname_ips,
2470 if ((plugin->behind_nat == GNUNET_YES) && (inet_pton(AF_INET, plugin->external_address, &t4.ipv4_addr) == 1))
2472 t4.t_port = htons(0);
2473 plugin->env->notify_address (plugin->env->cls,
2475 &t4, sizeof(t4), GNUNET_TIME_UNIT_FOREVER_REL);
2477 else if ((plugin->external_address != NULL) && (inet_pton(AF_INET, plugin->external_address, &t4.ipv4_addr) == 1))
2479 t4.t_port = htons(plugin->adv_port);
2480 plugin->env->notify_address (plugin->env->cls,
2482 &t4, sizeof(t4), GNUNET_TIME_UNIT_FOREVER_REL);
2490 * Exit point from the plugin.
2493 libgnunet_plugin_transport_tcp_done (void *cls)
2495 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
2496 struct Plugin *plugin = api->cls;
2497 struct Session *session;
2498 struct LocalAddrList *lal;
2500 while (NULL != (session = plugin->sessions))
2501 disconnect_session (session);
2502 if (NULL != plugin->hostname_dns)
2504 GNUNET_RESOLVER_request_cancel (plugin->hostname_dns);
2505 plugin->hostname_dns = NULL;
2507 GNUNET_SERVICE_stop (plugin->service);
2508 GNUNET_free (plugin->handlers);
2509 while (NULL != (lal = plugin->lal_head))
2511 GNUNET_CONTAINER_DLL_remove (plugin->lal_head,
2516 GNUNET_free (plugin);
2521 /* end of plugin_transport_tcp.c */