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_YES
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 (GNUNET_ERROR_TYPE_ERROR,
521 _("Unexpected address length: %u\n"),
526 if (NULL == inet_ntop (af, sb, buf, INET6_ADDRSTRLEN))
528 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
531 GNUNET_snprintf (rbuf,
533 (af == AF_INET6) ? "[%s]:%u" : "%s:%u",
541 * Find the session handle for the given client.
543 * @return NULL if no matching session exists
545 static struct Session *
546 find_session_by_client (struct Plugin *plugin,
547 const struct GNUNET_SERVER_Client *client)
551 ret = plugin->sessions;
552 while ((ret != NULL) && (client != ret->client))
558 * Create a new session. Also queues a welcome message.
561 * @param target peer to connect to
562 * @param client client to use
563 * @param is_nat this a NAT session, we should wait for a client to
564 * connect to us from an address, then assign that to
566 * @return new session object
568 static struct Session *
569 create_session (struct Plugin *plugin,
570 const struct GNUNET_PeerIdentity *target,
571 struct GNUNET_SERVER_Client *client, int is_nat)
574 struct PendingMessage *pm;
575 struct WelcomeMessage welcome;
577 if (is_nat != GNUNET_YES)
578 GNUNET_assert (client != NULL);
580 GNUNET_assert (client == NULL);
583 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
585 "Creating new session for peer `%4s'\n",
586 GNUNET_i2s (target));
588 ret = GNUNET_malloc (sizeof (struct Session));
589 ret->last_activity = GNUNET_TIME_absolute_get ();
590 ret->plugin = plugin;
591 if (is_nat != GNUNET_YES) /* If not a NAT WAIT conn, add it to global list */
593 ret->next = plugin->sessions;
594 plugin->sessions = ret;
596 ret->client = client;
597 ret->target = *target;
598 ret->expecting_welcome = GNUNET_YES;
599 pm = GNUNET_malloc (sizeof (struct PendingMessage) + sizeof (struct WelcomeMessage));
600 pm->msg = (const char*) &pm[1];
601 pm->message_size = sizeof (struct WelcomeMessage);
602 welcome.header.size = htons (sizeof (struct WelcomeMessage));
603 welcome.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME);
604 welcome.clientIdentity = *plugin->env->my_identity;
605 memcpy (&pm[1], &welcome, sizeof (welcome));
606 pm->timeout = GNUNET_TIME_UNIT_FOREVER_ABS;
607 GNUNET_STATISTICS_update (plugin->env->stats,
608 gettext_noop ("# bytes currently in TCP buffers"),
611 GNUNET_CONTAINER_DLL_insert (ret->pending_messages_head,
612 ret->pending_messages_tail,
614 if (is_nat != GNUNET_YES)
615 GNUNET_STATISTICS_update (plugin->env->stats,
616 gettext_noop ("# TCP sessions active"),
624 * If we have pending messages, ask the server to
625 * transmit them (schedule the respective tasks, etc.)
627 * @param session for which session should we do this
629 static void process_pending_messages (struct Session *session);
633 * Function called to notify a client about the socket
634 * being ready to queue more data. "buf" will be
635 * NULL and "size" zero if the socket was closed for
636 * writing in the meantime.
639 * @param size number of bytes available in buf
640 * @param buf where the callee should write the message
641 * @return number of bytes written to buf
644 do_transmit (void *cls, size_t size, void *buf)
646 struct Session *session = cls;
647 struct GNUNET_PeerIdentity pid;
648 struct Plugin *plugin;
649 struct PendingMessage *pos;
650 struct PendingMessage *hd;
651 struct PendingMessage *tl;
652 struct GNUNET_TIME_Absolute now;
656 session->transmit_handle = NULL;
657 plugin = session->plugin;
661 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
663 "Timeout trying to transmit to peer `%4s', discarding message queue.\n",
664 GNUNET_i2s (&session->target));
666 /* timeout; cancel all messages that have already expired */
670 now = GNUNET_TIME_absolute_get ();
671 while ( (NULL != (pos = session->pending_messages_head)) &&
672 (pos->timeout.value <= now.value) )
674 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
675 session->pending_messages_tail,
678 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
680 "Failed to transmit %u byte message to `%4s'.\n",
682 GNUNET_i2s (&session->target));
684 ret += pos->message_size;
685 GNUNET_CONTAINER_DLL_insert_after (hd, tl, tl, pos);
687 /* do this call before callbacks (so that if callbacks destroy
688 session, they have a chance to cancel actions done by this
690 process_pending_messages (session);
691 pid = session->target;
692 /* no do callbacks and do not use session again since
693 the callbacks may abort the session */
694 while (NULL != (pos = hd))
696 GNUNET_CONTAINER_DLL_remove (hd, tl, pos);
697 if (pos->transmit_cont != NULL)
698 pos->transmit_cont (pos->transmit_cont_cls,
699 &pid, GNUNET_SYSERR);
702 GNUNET_STATISTICS_update (plugin->env->stats,
703 gettext_noop ("# bytes currently in TCP buffers"),
706 GNUNET_STATISTICS_update (plugin->env->stats,
707 gettext_noop ("# bytes discarded by TCP (timeout)"),
712 /* copy all pending messages that would fit */
717 while (NULL != (pos = session->pending_messages_head))
719 if (ret + pos->message_size > size)
721 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
722 session->pending_messages_tail,
724 GNUNET_assert (size >= pos->message_size);
725 /* FIXME: this memcpy can be up to 7% of our total runtime */
726 memcpy (cbuf, pos->msg, pos->message_size);
727 cbuf += pos->message_size;
728 ret += pos->message_size;
729 size -= pos->message_size;
730 GNUNET_CONTAINER_DLL_insert_after (hd, tl, tl, pos);
732 /* schedule 'continuation' before callbacks so that callbacks that
733 cancel everything don't cause us to use a session that no longer
735 process_pending_messages (session);
736 session->last_activity = GNUNET_TIME_absolute_get ();
737 pid = session->target;
738 /* we'll now call callbacks that may cancel the session; hence
739 we should not use 'session' after this point */
740 while (NULL != (pos = hd))
742 GNUNET_CONTAINER_DLL_remove (hd, tl, pos);
743 if (pos->transmit_cont != NULL)
744 pos->transmit_cont (pos->transmit_cont_cls,
748 GNUNET_assert (hd == NULL);
749 GNUNET_assert (tl == NULL);
751 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
752 "tcp", "Transmitting %u bytes\n", ret);
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))
782 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "processing a pending message\n");
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 (GNUNET_ERROR_TYPE_DEBUG,
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 (GNUNET_ERROR_TYPE_DEBUG,
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 (GNUNET_ERROR_TYPE_ERROR,
1144 _("Address of unexpected length: %u\n"),
1150 if ((is_natd == GNUNET_YES) && (addrlen == sizeof (struct IPv6TcpAddress)))
1151 return -1; /* NAT client only works with IPv4 addresses */
1154 if ( (plugin->allow_nat == GNUNET_YES) && (is_natd == GNUNET_YES) &&
1155 (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns, &target->hashPubKey)))
1158 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1159 _("Found valid IPv4 NAT address!\n"));
1161 session = create_session (plugin,
1165 /* create new message entry */
1166 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msgbuf_size);
1167 /* FIXME: the memset of this malloc can be up to 2% of our total runtime */
1168 pm->msg = (const char*) &pm[1];
1169 memcpy (&pm[1], msg, msgbuf_size);
1170 /* FIXME: this memcpy can be up to 7% of our total run-time
1171 (for transport service) */
1172 pm->message_size = msgbuf_size;
1173 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1174 pm->transmit_cont = cont;
1175 pm->transmit_cont_cls = cont_cls;
1177 /* append pm to pending_messages list */
1178 GNUNET_CONTAINER_DLL_insert_after (session->pending_messages_head,
1179 session->pending_messages_tail,
1180 session->pending_messages_tail,
1183 GNUNET_assert(GNUNET_CONTAINER_multihashmap_put(plugin->nat_wait_conns, &target->hashPubKey, session, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY) == GNUNET_OK);
1185 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1186 "Created NAT WAIT connection to `%4s' at `%s'\n",
1187 GNUNET_i2s (target),
1188 GNUNET_a2s (sb, sbs));
1190 run_gnunet_nat_client(plugin, sb, sbs);
1193 else if ((plugin->allow_nat == GNUNET_YES) && (is_natd == GNUNET_YES) && (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns, &target->hashPubKey)))
1195 /* Only do one NAT punch attempt per peer identity */
1198 sa = GNUNET_CONNECTION_create_from_sockaddr (plugin->env->sched,
1203 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1205 "Failed to create connection to `%4s' at `%s'\n",
1206 GNUNET_i2s (target),
1207 GNUNET_a2s (sb, sbs));
1209 GNUNET_STATISTICS_update (plugin->env->stats,
1210 gettext_noop ("# bytes discarded by TCP (failed to connect)"),
1216 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1218 "Asked to transmit to `%4s', creating fresh session using address `%s'.\n",
1219 GNUNET_i2s (target),
1220 GNUNET_a2s (sb, sbs));
1222 session = create_session (plugin,
1224 GNUNET_SERVER_connect_socket (plugin->server,
1226 session->connect_addr = GNUNET_malloc (addrlen);
1227 memcpy (session->connect_addr,
1230 session->connect_alen = addrlen;
1232 GNUNET_assert (session != NULL);
1233 GNUNET_assert (session->client != NULL);
1234 GNUNET_STATISTICS_update (plugin->env->stats,
1235 gettext_noop ("# bytes currently in TCP buffers"),
1238 /* create new message entry */
1239 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msgbuf_size);
1240 pm->msg = (const char*) &pm[1];
1241 memcpy (&pm[1], msg, msgbuf_size);
1242 pm->message_size = msgbuf_size;
1243 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1244 pm->transmit_cont = cont;
1245 pm->transmit_cont_cls = cont_cls;
1247 /* append pm to pending_messages list */
1248 GNUNET_CONTAINER_DLL_insert_after (session->pending_messages_head,
1249 session->pending_messages_tail,
1250 session->pending_messages_tail,
1253 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1255 "Asked to transmit %u bytes to `%s', added message to list.\n",
1257 GNUNET_i2s (target));
1259 process_pending_messages (session);
1265 * Function that can be called to force a disconnect from the
1266 * specified neighbour. This should also cancel all previously
1267 * scheduled transmissions. Obviously the transmission may have been
1268 * partially completed already, which is OK. The plugin is supposed
1269 * to close the connection (if applicable) and no longer call the
1270 * transmit continuation(s).
1272 * Finally, plugin MUST NOT call the services's receive function to
1273 * notify the service that the connection to the specified target was
1274 * closed after a getting this call.
1276 * @param cls closure
1277 * @param target peer for which the last transmission is
1281 tcp_plugin_disconnect (void *cls,
1282 const struct GNUNET_PeerIdentity *target)
1284 struct Plugin *plugin = cls;
1285 struct Session *session;
1286 struct Session *next;
1287 struct PendingMessage *pm;
1290 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1292 "Asked to cancel session with `%4s'\n",
1293 GNUNET_i2s (target));
1295 next = plugin->sessions;
1296 while (NULL != (session = next))
1298 next = session->next;
1299 if (0 != memcmp (target,
1301 sizeof (struct GNUNET_PeerIdentity)))
1303 pm = session->pending_messages_head;
1306 pm->transmit_cont = NULL;
1307 pm->transmit_cont_cls = NULL;
1310 disconnect_session (session);
1316 * Context for address to string conversion.
1318 struct PrettyPrinterContext
1321 * Function to call with the result.
1323 GNUNET_TRANSPORT_AddressStringCallback asc;
1326 * Clsoure for 'asc'.
1331 * Port to add after the IP address.
1338 * Append our port and forward the result.
1340 * @param cls the 'struct PrettyPrinterContext*'
1341 * @param hostname hostname part of the address
1344 append_port (void *cls, const char *hostname)
1346 struct PrettyPrinterContext *ppc = cls;
1349 if (hostname == NULL)
1351 ppc->asc (ppc->asc_cls, NULL);
1355 GNUNET_asprintf (&ret, "%s:%d", hostname, ppc->port);
1356 ppc->asc (ppc->asc_cls, ret);
1362 * Convert the transports address to a nice, human-readable
1365 * @param cls closure
1366 * @param type name of the transport that generated the address
1367 * @param addr one of the addresses of the host, NULL for the last address
1368 * the specific address format depends on the transport
1369 * @param addrlen length of the address
1370 * @param numeric should (IP) addresses be displayed in numeric form?
1371 * @param timeout after how long should we give up?
1372 * @param asc function to call on each string
1373 * @param asc_cls closure for asc
1376 tcp_plugin_address_pretty_printer (void *cls,
1381 struct GNUNET_TIME_Relative timeout,
1382 GNUNET_TRANSPORT_AddressStringCallback asc,
1385 struct Plugin *plugin = cls;
1386 struct PrettyPrinterContext *ppc;
1389 struct sockaddr_in a4;
1390 struct sockaddr_in6 a6;
1391 const struct IPv4TcpAddress *t4;
1392 const struct IPv6TcpAddress *t6;
1395 if (addrlen == sizeof (struct IPv6TcpAddress))
1398 memset (&a6, 0, sizeof (a6));
1399 a6.sin6_family = AF_INET6;
1400 a6.sin6_port = t6->t6_port;
1401 memcpy (&a6.sin6_addr,
1403 sizeof (struct in6_addr));
1404 port = ntohs (t6->t6_port);
1408 else if (addrlen == sizeof (struct IPv4TcpAddress))
1411 memset (&a4, 0, sizeof (a4));
1412 a4.sin_family = AF_INET;
1413 a4.sin_port = t4->t_port;
1414 a4.sin_addr.s_addr = t4->ipv4_addr;
1415 port = ntohs (t4->t_port);
1421 /* invalid address */
1422 GNUNET_break_op (0);
1423 asc (asc_cls, NULL);
1426 ppc = GNUNET_malloc (sizeof (struct PrettyPrinterContext));
1428 ppc->asc_cls = asc_cls;
1430 GNUNET_RESOLVER_hostname_get (plugin->env->sched,
1434 !numeric, timeout, &append_port, ppc);
1439 * Check if the given port is plausible (must be either
1440 * our listen port or our advertised port). If it is
1441 * neither, we return GNUNET_SYSERR.
1443 * @param plugin global variables
1444 * @param in_port port number to check
1445 * @return GNUNET_OK if port is either open_port or adv_port
1448 check_port (struct Plugin *plugin, uint16_t in_port)
1450 if ( (plugin->behind_nat == GNUNET_YES) && (in_port == 0) )
1452 if ( (plugin->only_nat_addresses == GNUNET_YES) &&
1453 (plugin->behind_nat == GNUNET_YES) )
1455 return GNUNET_SYSERR; /* odd case... */
1457 if ((in_port == plugin->adv_port) || (in_port == plugin->open_port))
1459 return GNUNET_SYSERR;
1464 * Function that will be called to check if a binary address for this
1465 * plugin is well-formed and corresponds to an address for THIS peer
1466 * (as per our configuration). Naturally, if absolutely necessary,
1467 * plugins can be a bit conservative in their answer, but in general
1468 * plugins should make sure that the address does not redirect
1469 * traffic to a 3rd party that might try to man-in-the-middle our
1472 * @param cls closure, our 'struct Plugin*'
1473 * @param addr pointer to the address
1474 * @param addrlen length of addr
1475 * @return GNUNET_OK if this is a plausible address for this peer
1476 * and transport, GNUNET_SYSERR if not
1479 tcp_plugin_check_address (void *cls,
1483 struct Plugin *plugin = cls;
1484 struct IPv4TcpAddress *v4;
1485 struct IPv6TcpAddress *v6;
1487 if ((addrlen != sizeof (struct IPv4TcpAddress)) &&
1488 (addrlen != sizeof (struct IPv6TcpAddress)))
1490 GNUNET_break_op (0);
1491 return GNUNET_SYSERR;
1493 if (addrlen == sizeof (struct IPv4TcpAddress))
1495 v4 = (struct IPv4TcpAddress *) addr;
1497 check_port (plugin, ntohs (v4->t_port)))
1498 return GNUNET_SYSERR;
1500 check_local_addr (plugin, &v4->ipv4_addr, sizeof (uint32_t)))
1502 return GNUNET_SYSERR;
1507 v6 = (struct IPv6TcpAddress *) addr;
1508 if (IN6_IS_ADDR_LINKLOCAL (&v6->ipv6_addr))
1510 GNUNET_break_op (0);
1511 return GNUNET_SYSERR;
1514 check_port (plugin, ntohs (v6->t6_port)))
1515 return GNUNET_SYSERR;
1517 check_local_addr (plugin, &v6->ipv6_addr, sizeof (struct in6_addr)))
1519 return GNUNET_SYSERR;
1526 * We've received a nat probe from this peer via TCP. Finish
1527 * creating the client session and resume sending of queued
1530 * @param cls closure
1531 * @param client identification of the client
1532 * @param message the actual message
1535 handle_tcp_nat_probe (void *cls,
1536 struct GNUNET_SERVER_Client *client,
1537 const struct GNUNET_MessageHeader *message)
1539 struct Plugin *plugin = cls;
1540 struct Session *session;
1541 struct TCP_NAT_ProbeMessage *tcp_nat_probe;
1544 struct IPv4TcpAddress *t4;
1545 struct IPv6TcpAddress *t6;
1546 const struct sockaddr_in *s4;
1547 const struct sockaddr_in6 *s6;
1550 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "received tcp NAT probe\n");
1552 /* We have received a TCP NAT probe, meaning we (hopefully) initiated
1553 * a connection to this peer by running gnunet-nat-client. This peer
1554 * received the punch message and now wants us to use the new connection
1555 * as the default for that peer. Do so and then send a WELCOME message
1556 * so we can really be connected!
1558 if (ntohs(message->size) != sizeof(struct TCP_NAT_ProbeMessage))
1561 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Bad size for tcp NAT probe, expected %d got %d.\n", sizeof(struct TCP_NAT_ProbeMessage), ntohs(message->size));
1566 tcp_nat_probe = (struct TCP_NAT_ProbeMessage *)message;
1568 if (GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns, &tcp_nat_probe->clientIdentity.hashPubKey) == GNUNET_YES)
1571 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Found session for NAT probe!\n");
1573 session = GNUNET_CONTAINER_multihashmap_get(plugin->nat_wait_conns, &tcp_nat_probe->clientIdentity.hashPubKey);
1574 GNUNET_assert(session != NULL);
1575 GNUNET_assert(GNUNET_CONTAINER_multihashmap_remove(plugin->nat_wait_conns, &tcp_nat_probe->clientIdentity.hashPubKey, session) == GNUNET_YES);
1576 GNUNET_SERVER_client_keep (client);
1577 session->client = client;
1578 session->last_activity = GNUNET_TIME_absolute_get ();
1581 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1584 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1585 "Found address `%s' for incoming connection %p\n",
1586 GNUNET_a2s (vaddr, alen),
1589 if (alen == sizeof (struct sockaddr_in))
1592 t4 = GNUNET_malloc (sizeof (struct IPv4TcpAddress));
1593 t4->t_port = s4->sin_port;
1594 t4->ipv4_addr = s4->sin_addr.s_addr;
1595 session->connect_addr = t4;
1596 session->connect_alen = sizeof (struct IPv4TcpAddress);
1598 else if (alen == sizeof (struct sockaddr_in6))
1601 t6 = GNUNET_malloc (sizeof (struct IPv6TcpAddress));
1602 t6->t6_port = s6->sin6_port;
1603 memcpy (&t6->ipv6_addr,
1605 sizeof (struct in6_addr));
1606 session->connect_addr = t6;
1607 session->connect_alen = sizeof (struct IPv6TcpAddress);
1610 session->connect_addr = GNUNET_malloc (alen);
1611 memcpy (session->connect_addr,
1614 session->connect_alen = alen;
1615 GNUNET_free (vaddr);
1618 session->next = plugin->sessions;
1619 plugin->sessions = session;
1620 GNUNET_STATISTICS_update (plugin->env->stats,
1621 gettext_noop ("# TCP sessions active"),
1624 process_pending_messages (session);
1629 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Did NOT find session for NAT probe!\n");
1635 * We've received a welcome from this peer via TCP. Possibly create a
1636 * fresh client record and send back our welcome.
1638 * @param cls closure
1639 * @param client identification of the client
1640 * @param message the actual message
1643 handle_tcp_welcome (void *cls,
1644 struct GNUNET_SERVER_Client *client,
1645 const struct GNUNET_MessageHeader *message)
1647 struct Plugin *plugin = cls;
1648 const struct WelcomeMessage *wm = (const struct WelcomeMessage *) message;
1649 struct Session *session;
1652 struct IPv4TcpAddress *t4;
1653 struct IPv6TcpAddress *t6;
1654 const struct sockaddr_in *s4;
1655 const struct sockaddr_in6 *s6;
1659 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1661 "Received %s message from a `%4s/%p'.\n",
1663 GNUNET_i2s (&wm->clientIdentity), client);
1665 GNUNET_STATISTICS_update (plugin->env->stats,
1666 gettext_noop ("# TCP WELCOME messages received"),
1669 session = find_session_by_client (plugin, client);
1670 if (session == NULL)
1672 GNUNET_SERVER_client_keep (client);
1673 session = create_session (plugin,
1674 &wm->clientIdentity, client, GNUNET_NO);
1675 session->inbound = GNUNET_YES;
1677 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1680 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1682 "Found address `%s' for incoming connection %p\n",
1683 GNUNET_a2s (vaddr, alen),
1686 if (alen == sizeof (struct sockaddr_in))
1689 t4 = GNUNET_malloc (sizeof (struct IPv4TcpAddress));
1690 t4->t_port = s4->sin_port;
1691 t4->ipv4_addr = s4->sin_addr.s_addr;
1692 session->connect_addr = t4;
1693 session->connect_alen = sizeof (struct IPv4TcpAddress);
1695 else if (alen == sizeof (struct sockaddr_in6))
1698 t6 = GNUNET_malloc (sizeof (struct IPv6TcpAddress));
1699 t6->t6_port = s6->sin6_port;
1700 memcpy (&t6->ipv6_addr,
1702 sizeof (struct in6_addr));
1703 session->connect_addr = t6;
1704 session->connect_alen = sizeof (struct IPv6TcpAddress);
1706 GNUNET_free (vaddr);
1711 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1713 "Did not obtain TCP socket address for incoming connection\n");
1717 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1719 "Creating new session %p for connection %p\n",
1722 process_pending_messages (session);
1724 if (session->expecting_welcome != GNUNET_YES)
1726 GNUNET_break_op (0);
1727 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1730 session->last_activity = GNUNET_TIME_absolute_get ();
1731 session->expecting_welcome = GNUNET_NO;
1732 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1737 * Task to signal the server that we can continue
1738 * receiving from the TCP client now.
1740 * @param cls the 'struct Session*'
1741 * @param tc task context (unused)
1744 delayed_done (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1746 struct Session *session = cls;
1747 struct GNUNET_TIME_Relative delay;
1749 session->receive_delay_task = GNUNET_SCHEDULER_NO_TASK;
1750 delay = session->plugin->env->receive (session->plugin->env->cls,
1755 if (delay.value == 0)
1756 GNUNET_SERVER_receive_done (session->client, GNUNET_OK);
1758 session->receive_delay_task =
1759 GNUNET_SCHEDULER_add_delayed (session->plugin->env->sched,
1760 delay, &delayed_done, session);
1765 * We've received data for this peer via TCP. Unbox,
1766 * compute latency and forward.
1768 * @param cls closure
1769 * @param client identification of the client
1770 * @param message the actual message
1773 handle_tcp_data (void *cls,
1774 struct GNUNET_SERVER_Client *client,
1775 const struct GNUNET_MessageHeader *message)
1777 struct Plugin *plugin = cls;
1778 struct Session *session;
1779 struct GNUNET_TIME_Relative delay;
1781 if ((GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME == ntohs(message->type)) || (ntohs(message->type) == GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE))
1783 /* We don't want to propagate WELCOME and NAT Probe messages up! */
1784 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1787 session = find_session_by_client (plugin, client);
1788 if ( (NULL == session) || (GNUNET_YES == session->expecting_welcome))
1790 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1793 session->last_activity = GNUNET_TIME_absolute_get ();
1795 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1797 "Passing %u bytes of type %u from `%4s' to transport service.\n",
1798 (unsigned int) ntohs (message->size),
1799 (unsigned int) ntohs (message->type),
1800 GNUNET_i2s (&session->target));
1802 GNUNET_STATISTICS_update (plugin->env->stats,
1803 gettext_noop ("# bytes received via TCP"),
1804 ntohs (message->size),
1806 delay = plugin->env->receive (plugin->env->cls, &session->target, message, 1,
1808 (GNUNET_YES == session->inbound) ? NULL : session->connect_addr,
1809 (GNUNET_YES == session->inbound) ? 0 : session->connect_alen);
1810 if (delay.value == 0)
1811 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1813 session->receive_delay_task =
1814 GNUNET_SCHEDULER_add_delayed (session->plugin->env->sched,
1815 delay, &delayed_done, session);
1820 * Functions with this signature are called whenever a peer
1821 * is disconnected on the network level.
1823 * @param cls closure
1824 * @param client identification of the client
1827 disconnect_notify (void *cls,
1828 struct GNUNET_SERVER_Client *client)
1830 struct Plugin *plugin = cls;
1831 struct Session *session;
1835 session = find_session_by_client (plugin, client);
1836 if (session == NULL)
1837 return; /* unknown, nothing to do */
1839 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1841 "Destroying session of `%4s' with %s (%p) due to network-level disconnect.\n",
1842 GNUNET_i2s (&session->target),
1843 (session->connect_addr != NULL) ?
1844 tcp_address_to_string (session->plugin,
1845 session->connect_addr,
1846 session->connect_alen) : "*",
1849 disconnect_session (session);
1854 * Add the IP of our network interface to the list of
1855 * our external IP addresses.
1857 * @param cls the 'struct Plugin*'
1858 * @param name name of the interface
1859 * @param isDefault do we think this may be our default interface
1860 * @param addr address of the interface
1861 * @param addrlen number of bytes in addr
1862 * @return GNUNET_OK to continue iterating
1865 process_interfaces (void *cls,
1868 const struct sockaddr *addr, socklen_t addrlen)
1870 struct Plugin *plugin = cls;
1872 struct IPv4TcpAddress t4;
1873 struct IPv6TcpAddress t6;
1874 struct IPv4TcpAddress t4_nat;
1875 struct IPv6TcpAddress t6_nat;
1880 af = addr->sa_family;
1884 t4.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
1885 add_to_address_list (plugin, &t4.ipv4_addr, sizeof (uint32_t));
1886 if ((plugin->behind_nat == GNUNET_YES) && (plugin->only_nat_addresses == GNUNET_YES))
1887 t4.t_port = htons(0);
1888 else if (plugin->behind_nat == GNUNET_YES) /* We are behind NAT, but will advertise NAT and normal addresses */
1890 t4_nat.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
1891 t4_nat.t_port = htons(plugin->adv_port);
1895 t4.t_port = htons (plugin->adv_port);
1899 else if (af == AF_INET6)
1901 if (IN6_IS_ADDR_LINKLOCAL (&((struct sockaddr_in6 *) addr)->sin6_addr))
1903 /* skip link local addresses */
1906 memcpy (&t6.ipv6_addr,
1907 &((struct sockaddr_in6 *) addr)->sin6_addr,
1908 sizeof (struct in6_addr));
1909 add_to_address_list (plugin, &t6.ipv6_addr, sizeof (struct in6_addr));
1910 if ((plugin->behind_nat == GNUNET_YES) && (plugin->only_nat_addresses == GNUNET_YES))
1911 t6.t6_port = htons(0);
1912 else if (plugin->behind_nat == GNUNET_YES) /* We are behind NAT, but will advertise NAT and normal addresses */
1914 memcpy (&t6_nat.ipv6_addr,
1915 &((struct sockaddr_in6 *) addr)->sin6_addr,
1916 sizeof (struct in6_addr));
1917 t6_nat.t6_port = htons(plugin->adv_port);
1921 t6.t6_port = htons (plugin->adv_port);
1930 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO |
1931 GNUNET_ERROR_TYPE_BULK,
1933 _("Found address `%s' (%s)\n"),
1934 GNUNET_a2s (addr, addrlen), name);
1936 plugin->env->notify_address (plugin->env->cls,
1938 arg, args, GNUNET_TIME_UNIT_FOREVER_REL);
1940 if (arg_nat != NULL)
1942 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO |
1943 GNUNET_ERROR_TYPE_BULK,
1945 _("Found address `%s' (%s)\n"),
1946 GNUNET_a2s (addr, addrlen), name);
1947 plugin->env->notify_address (plugin->env->cls,
1949 arg_nat, args, GNUNET_TIME_UNIT_FOREVER_REL);
1957 * Function called by the resolver for each address obtained from DNS
1958 * for our own hostname. Add the addresses to the list of our
1959 * external IP addresses.
1961 * @param cls closure
1962 * @param addr one of the addresses of the host, NULL for the last address
1963 * @param addrlen length of the address
1966 process_hostname_ips (void *cls,
1967 const struct sockaddr *addr, socklen_t addrlen)
1969 struct Plugin *plugin = cls;
1973 plugin->hostname_dns = NULL;
1976 /* FIXME: Can we figure out our external address here so it doesn't need to be user specified? */
1977 process_interfaces (plugin, "<hostname>", GNUNET_YES, addr, addrlen);
1981 * We can now send a probe message, copy into buffer to really send.
1983 * @param cls closure, a struct TCPProbeContext
1984 * @param size max size to copy
1985 * @param buf buffer to copy message to
1987 static size_t notify_send_probe (void *cls,
1988 size_t size, void *buf)
1990 struct TCPProbeContext *tcp_probe_ctx = cls;
1997 GNUNET_assert(size >= sizeof(tcp_probe_ctx->message));
1998 memcpy(buf, &tcp_probe_ctx->message, sizeof(tcp_probe_ctx->message));
1999 GNUNET_SERVER_connect_socket (tcp_probe_ctx->plugin->server,
2000 tcp_probe_ctx->sock);
2002 GNUNET_free(tcp_probe_ctx);
2003 return sizeof(tcp_probe_ctx->message);
2007 * @param cls the plugin handle
2008 * @param tc the scheduling context (for rescheduling this function again)
2010 * We have been notified that gnunet-nat-server has written something to stdout.
2011 * Handle the output, then reschedule this function to be called again once
2012 * more is available.
2016 tcp_plugin_server_read (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
2018 struct Plugin *plugin = cls;
2021 memset(&mybuf, 0, sizeof(mybuf));
2025 struct sockaddr_in in_addr;
2026 struct TCPProbeContext *tcp_probe_ctx;
2027 struct GNUNET_CONNECTION_Handle *sock;
2029 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
2032 bytes = GNUNET_DISK_file_read(plugin->server_stdout_handle, &mybuf, sizeof(mybuf));
2037 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "tcp",
2038 _("Finished reading from server stdout with code: %d\n"), bytes);
2045 for (i = 0; i < sizeof(mybuf); i++)
2047 if (mybuf[i] == '\n')
2050 if ((mybuf[i] == ':') && (i + 1 < sizeof(mybuf)))
2053 port_start = &mybuf[i + 1];
2057 if (port_start != NULL)
2058 port = atoi(port_start);
2061 plugin->server_read_task =
2062 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2063 GNUNET_TIME_UNIT_FOREVER_REL,
2064 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2069 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2070 _("nat-server-read read: %s port %d\n"), &mybuf, port);
2074 if (inet_pton(AF_INET, &mybuf[0], &in_addr.sin_addr) != 1)
2077 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2078 _("nat-server-read malformed address\n"), &mybuf, port);
2080 plugin->server_read_task =
2081 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2082 GNUNET_TIME_UNIT_FOREVER_REL,
2083 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2087 in_addr.sin_family = AF_INET;
2088 in_addr.sin_port = htons(port);
2090 * We have received an ICMP response, ostensibly from a non-NAT'd peer
2091 * that wants to connect to us! Send a message to establish a connection.
2093 sock = GNUNET_CONNECTION_create_from_sockaddr (plugin->env->sched, AF_INET, (struct sockaddr *)&in_addr,
2097 plugin->server_read_task =
2098 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2099 GNUNET_TIME_UNIT_FOREVER_REL,
2100 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2105 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2106 _("Sending TCP probe message!\n"), &mybuf, port);
2107 tcp_probe_ctx = GNUNET_malloc(sizeof(struct TCPProbeContext));
2109 tcp_probe_ctx->message.header.size = htons(sizeof(struct TCP_NAT_ProbeMessage));
2110 tcp_probe_ctx->message.header.type = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE);
2111 memcpy(&tcp_probe_ctx->message.clientIdentity, plugin->env->my_identity, sizeof(struct GNUNET_PeerIdentity));
2112 tcp_probe_ctx->plugin = plugin;
2113 tcp_probe_ctx->sock = sock;
2114 tcp_probe_ctx->transmit_handle = GNUNET_CONNECTION_notify_transmit_ready (sock,
2115 ntohs(tcp_probe_ctx->message.header.size),
2116 GNUNET_TIME_UNIT_FOREVER_REL,
2117 ¬ify_send_probe, tcp_probe_ctx);
2121 plugin->server_read_task =
2122 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2123 GNUNET_TIME_UNIT_FOREVER_REL,
2124 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2128 * Start the gnunet-nat-server process for users behind NAT.
2130 * @param plugin the transport plugin
2132 * @return GNUNET_YES if process was started, GNUNET_SYSERR on error
2135 tcp_transport_start_nat_server(struct Plugin *plugin)
2138 plugin->server_stdout = GNUNET_DISK_pipe(GNUNET_YES);
2139 if (plugin->server_stdout == NULL)
2140 return GNUNET_SYSERR;
2143 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2144 "Starting gnunet-nat-server process cmd: %s %s\n", "gnunet-nat-server", plugin->internal_address);
2146 /* Start the server process */
2147 plugin->server_pid = GNUNET_OS_start_process(NULL, plugin->server_stdout, "gnunet-nat-server", "gnunet-nat-server", plugin->internal_address, NULL);
2148 if (plugin->server_pid == GNUNET_SYSERR)
2151 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2152 "Failed to start gnunet-nat-server process\n");
2154 return GNUNET_SYSERR;
2156 /* Close the write end of the read pipe */
2157 GNUNET_DISK_pipe_close_end(plugin->server_stdout, GNUNET_DISK_PIPE_END_WRITE);
2159 plugin->server_stdout_handle = GNUNET_DISK_pipe_handle(plugin->server_stdout, GNUNET_DISK_PIPE_END_READ);
2160 plugin->server_read_task =
2161 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2162 GNUNET_TIME_UNIT_FOREVER_REL,
2163 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2168 * Return the actual path to a file found in the current
2169 * PATH environment variable.
2171 * @param binary the name of the file to find
2174 get_path_from_PATH (char *binary)
2182 p = getenv ("PATH");
2185 path = GNUNET_strdup (p); /* because we write on it */
2186 buf = GNUNET_malloc (strlen (path) + 20);
2189 while (NULL != (end = strchr (pos, ':')))
2192 sprintf (buf, "%s/%s", pos, binary);
2193 if (GNUNET_DISK_file_test (buf) == GNUNET_YES)
2200 sprintf (buf, "%s/%s", pos, binary);
2201 if (GNUNET_DISK_file_test (buf) == GNUNET_YES)
2212 * Check whether the suid bit is set on a file.
2213 * Attempts to find the file using the current
2214 * PATH environment variable as a search path.
2216 * @param binary the name of the file to check
2219 check_gnunet_nat_binary(char *binary)
2221 struct stat statbuf;
2224 p = get_path_from_PATH (binary);
2227 if (0 != STAT (p, &statbuf))
2230 return GNUNET_SYSERR;
2233 if ( (0 != (statbuf.st_mode & S_ISUID)) &&
2234 (statbuf.st_uid == 0) )
2240 * Entry point for the plugin.
2242 * @param cls closure, the 'struct GNUNET_TRANSPORT_PluginEnvironment*'
2243 * @return the 'struct GNUNET_TRANSPORT_PluginFunctions*' or NULL on error
2246 libgnunet_plugin_transport_tcp_init (void *cls)
2248 static const struct GNUNET_SERVER_MessageHandler my_handlers[] = {
2249 {&handle_tcp_welcome, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME,
2250 sizeof (struct WelcomeMessage)},
2251 {&handle_tcp_nat_probe, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE, sizeof (struct TCP_NAT_ProbeMessage)},
2252 {&handle_tcp_data, NULL, GNUNET_MESSAGE_TYPE_ALL, 0},
2255 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
2256 struct GNUNET_TRANSPORT_PluginFunctions *api;
2257 struct Plugin *plugin;
2258 struct GNUNET_SERVICE_Context *service;
2259 unsigned long long aport;
2260 unsigned long long bport;
2264 int only_nat_addresses;
2265 char *internal_address;
2266 char *external_address;
2267 struct sockaddr_in in_addr;
2268 struct IPv4TcpAddress t4;
2270 service = GNUNET_SERVICE_start ("transport-tcp", env->sched, env->cfg);
2271 if (service == NULL)
2273 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING,
2276 ("Failed to start service for `%s' transport plugin.\n"),
2281 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
2285 /* We are behind nat (according to the user) */
2286 if (check_gnunet_nat_binary("gnunet-nat-server") == GNUNET_YES)
2288 behind_nat = GNUNET_YES;
2292 behind_nat = GNUNET_NO;
2293 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");
2297 behind_nat = GNUNET_NO; /* We are not behind nat! */
2299 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
2303 if (check_gnunet_nat_binary("gnunet-nat-client") == GNUNET_YES)
2304 allow_nat = GNUNET_YES; /* We will try to connect to NAT'd peers */
2307 allow_nat = GNUNET_NO;
2308 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");
2312 allow_nat = GNUNET_NO; /* We don't want to try to help NAT'd peers */
2315 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
2317 "ONLY_NAT_ADDRESSES"))
2318 only_nat_addresses = GNUNET_YES; /* We will only report our addresses as NAT'd */
2320 only_nat_addresses = GNUNET_NO; /* We will report our addresses as NAT'd and non-NAT'd */
2322 external_address = NULL;
2323 if (((GNUNET_YES == behind_nat) || (GNUNET_YES == allow_nat)) && (GNUNET_OK !=
2324 GNUNET_CONFIGURATION_get_value_string (env->cfg,
2327 &external_address)))
2329 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2332 ("Require EXTERNAL_ADDRESS for service `%s' in configuration (either BEHIND_NAT or ALLOW_NAT set to YES)!\n"),
2334 GNUNET_SERVICE_stop (service);
2338 if ((external_address != NULL) && (inet_pton(AF_INET, external_address, &in_addr.sin_addr) != 1))
2340 GNUNET_log_from(GNUNET_ERROR_TYPE_WARNING, "udp", "Malformed EXTERNAL_ADDRESS %s given in configuration!\n", external_address);
2343 internal_address = NULL;
2344 if ((GNUNET_YES == behind_nat) && (GNUNET_OK !=
2345 GNUNET_CONFIGURATION_get_value_string (env->cfg,
2348 &internal_address)))
2350 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2353 ("Require INTERNAL_ADDRESS for service `%s' in configuration!\n"),
2355 GNUNET_SERVICE_stop (service);
2356 GNUNET_free_non_null(external_address);
2360 if ((internal_address != NULL) && (inet_pton(AF_INET, internal_address, &in_addr.sin_addr) != 1))
2362 GNUNET_log_from(GNUNET_ERROR_TYPE_WARNING, "udp", "Malformed INTERNAL_ADDRESS %s given in configuration!\n", internal_address);
2367 GNUNET_CONFIGURATION_get_value_number (env->cfg,
2373 GNUNET_CONFIGURATION_get_value_number (env->cfg,
2376 &aport)) && (aport > 65535)))
2378 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2381 ("Require valid port number for service `%s' in configuration!\n"),
2383 GNUNET_free_non_null(external_address);
2384 GNUNET_free_non_null(internal_address);
2385 GNUNET_SERVICE_stop (service);
2391 plugin = GNUNET_malloc (sizeof (struct Plugin));
2392 plugin->open_port = bport;
2393 plugin->adv_port = aport;
2394 plugin->external_address = external_address;
2395 plugin->internal_address = internal_address;
2396 plugin->behind_nat = behind_nat;
2397 plugin->allow_nat = allow_nat;
2398 plugin->only_nat_addresses = only_nat_addresses;
2400 plugin->lsock = NULL;
2401 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
2403 api->send = &tcp_plugin_send;
2404 api->disconnect = &tcp_plugin_disconnect;
2405 api->address_pretty_printer = &tcp_plugin_address_pretty_printer;
2406 api->check_address = &tcp_plugin_check_address;
2407 api->address_to_string = &tcp_address_to_string;
2408 plugin->service = service;
2409 plugin->server = GNUNET_SERVICE_get_server (service);
2410 plugin->handlers = GNUNET_malloc (sizeof (my_handlers));
2411 memcpy (plugin->handlers, my_handlers, sizeof (my_handlers));
2414 sizeof (my_handlers) / sizeof (struct GNUNET_SERVER_MessageHandler);
2416 plugin->handlers[i].callback_cls = plugin;
2417 GNUNET_SERVER_add_handlers (plugin->server, plugin->handlers);
2419 if (behind_nat == GNUNET_YES)
2421 if (GNUNET_YES != tcp_transport_start_nat_server(plugin))
2423 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
2426 ("Failed to start %s required for NAT in %s!\n"),
2429 GNUNET_free_non_null(external_address);
2430 GNUNET_free_non_null(internal_address);
2431 GNUNET_SERVICE_stop (service);
2437 if (allow_nat == GNUNET_YES)
2439 plugin->nat_wait_conns = GNUNET_CONTAINER_multihashmap_create(100);
2440 GNUNET_assert(plugin->nat_wait_conns != NULL);
2443 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2444 "tcp", _("TCP transport listening on port %llu\n"), bport);
2446 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2448 _("TCP transport advertises itself as being on port %llu\n"),
2450 GNUNET_SERVER_disconnect_notify (plugin->server,
2453 if (plugin->behind_nat == GNUNET_NO)
2455 GNUNET_OS_network_interfaces_list (&process_interfaces, plugin);
2458 plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (env->sched,
2461 HOSTNAME_RESOLVE_TIMEOUT,
2462 &process_hostname_ips,
2465 if ((plugin->behind_nat == GNUNET_YES) && (inet_pton(AF_INET, plugin->external_address, &t4.ipv4_addr) == 1))
2467 t4.t_port = htons(0);
2468 plugin->env->notify_address (plugin->env->cls,
2470 &t4, sizeof(t4), GNUNET_TIME_UNIT_FOREVER_REL);
2472 else if ((plugin->external_address != NULL) && (inet_pton(AF_INET, plugin->external_address, &t4.ipv4_addr) == 1))
2474 t4.t_port = htons(plugin->adv_port);
2475 plugin->env->notify_address (plugin->env->cls,
2477 &t4, sizeof(t4), GNUNET_TIME_UNIT_FOREVER_REL);
2485 * Exit point from the plugin.
2488 libgnunet_plugin_transport_tcp_done (void *cls)
2490 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
2491 struct Plugin *plugin = api->cls;
2492 struct Session *session;
2493 struct LocalAddrList *lal;
2495 while (NULL != (session = plugin->sessions))
2496 disconnect_session (session);
2497 if (NULL != plugin->hostname_dns)
2499 GNUNET_RESOLVER_request_cancel (plugin->hostname_dns);
2500 plugin->hostname_dns = NULL;
2502 GNUNET_SERVICE_stop (plugin->service);
2503 GNUNET_free (plugin->handlers);
2504 while (NULL != (lal = plugin->lal_head))
2506 GNUNET_CONTAINER_DLL_remove (plugin->lal_head,
2512 if (plugin->behind_nat == GNUNET_YES)
2514 if (0 != PLIBC_KILL (plugin->server_pid, SIGTERM))
2515 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "kill");
2516 GNUNET_OS_process_wait (plugin->server_pid);
2519 GNUNET_free (plugin);
2524 /* end of plugin_transport_tcp.c */