2 This file is part of GNUnet
3 (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
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13 General Public License for more details.
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21 * @file transport/plugin_transport_tcp.c
22 * @brief Implementation of the TCP transport service
23 * @author Christian Grothoff
26 #include "gnunet_hello_lib.h"
27 #include "gnunet_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_YES
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)
308 * Was this session created using NAT traversal?
316 * Encapsulation of all of the state of the plugin.
323 struct GNUNET_TRANSPORT_PluginEnvironment *env;
328 struct GNUNET_CONNECTION_Handle *lsock;
331 * stdout pipe handle for the gnunet-nat-server process
333 struct GNUNET_DISK_PipeHandle *server_stdout;
336 * stdout file handle (for reading) for the gnunet-nat-server process
338 const struct GNUNET_DISK_FileHandle *server_stdout_handle;
341 * ID of select gnunet-nat-server stdout read task
343 GNUNET_SCHEDULER_TaskIdentifier server_read_task;
346 * The process id of the server process (if behind NAT)
351 * List of open TCP sessions.
353 struct Session *sessions;
356 * Handle to the network service.
358 struct GNUNET_SERVICE_Context *service;
361 * Handle to the server for this service.
363 struct GNUNET_SERVER_Handle *server;
366 * Copy of the handler array where the closures are
367 * set to this struct's instance.
369 struct GNUNET_SERVER_MessageHandler *handlers;
372 * Handle for request of hostname resolution, non-NULL if pending.
374 struct GNUNET_RESOLVER_RequestHandle *hostname_dns;
377 * Map of peers we have tried to contact behind a NAT
379 struct GNUNET_CONTAINER_MultiHashMap *nat_wait_conns;
382 * The external address given to us by the user. Must be actual
383 * outside visible address for NAT punching to work.
385 char *external_address;
388 * The internal address given to us by the user (or discovered).
390 char *internal_address;
393 * Address given for us to bind to (ONLY).
398 * List of our IP addresses.
400 struct LocalAddrList *lal_head;
403 * Tail of our IP address list.
405 struct LocalAddrList *lal_tail;
408 * ID of task used to update our addresses when one expires.
410 GNUNET_SCHEDULER_TaskIdentifier address_update_task;
413 * Port that we are actually listening on.
418 * Port that the user said we would have visible to the
424 * Is this transport configured to be behind a NAT?
429 * Is this transport configured to allow connections to NAT'd peers?
434 * Should this transport advertise only NAT addresses (port set to 0)?
435 * If not, all addresses will be duplicated for NAT punching and regular
438 int only_nat_addresses;
444 add_to_address_list (struct Plugin *plugin,
448 struct LocalAddrList *lal;
450 lal = plugin->lal_head;
453 if ( (lal->size == arg_size) &&
454 (0 == memcmp (&lal[1], arg, arg_size)) )
458 lal = GNUNET_malloc (sizeof (struct LocalAddrList) + arg_size);
459 lal->size = arg_size;
460 memcpy (&lal[1], arg, arg_size);
461 GNUNET_CONTAINER_DLL_insert (plugin->lal_head,
468 check_local_addr (struct Plugin *plugin,
472 struct LocalAddrList *lal;
474 lal = plugin->lal_head;
477 if ( (lal->size == arg_size) &&
478 (0 == memcmp (&lal[1], arg, arg_size)) )
482 return GNUNET_SYSERR;
487 * Function called for a quick conversion of the binary address to
488 * a numeric address. Note that the caller must not free the
489 * address and that the next call to this function is allowed
490 * to override the address again.
492 * @param cls closure ('struct Plugin*')
493 * @param addr binary address
494 * @param addrlen length of the address
495 * @return string representing the same address
498 tcp_address_to_string (void *cls,
502 static char rbuf[INET6_ADDRSTRLEN + 12];
503 char buf[INET6_ADDRSTRLEN];
507 const struct IPv4TcpAddress *t4;
508 const struct IPv6TcpAddress *t6;
512 if (addrlen == sizeof (struct IPv6TcpAddress))
516 port = ntohs (t6->t6_port);
517 memcpy (&a6, &t6->ipv6_addr, sizeof (a6));
520 else if (addrlen == sizeof (struct IPv4TcpAddress))
524 port = ntohs (t4->t_port);
525 memcpy (&a4, &t4->ipv4_addr, sizeof (a4));
530 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
531 _("Unexpected address length: %u\n"),
536 if (NULL == inet_ntop (af, sb, buf, INET6_ADDRSTRLEN))
538 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
541 GNUNET_snprintf (rbuf,
543 (af == AF_INET6) ? "[%s]:%u" : "%s:%u",
551 * Find the session handle for the given client.
553 * @return NULL if no matching session exists
555 static struct Session *
556 find_session_by_client (struct Plugin *plugin,
557 const struct GNUNET_SERVER_Client *client)
561 ret = plugin->sessions;
562 while ((ret != NULL) && (client != ret->client))
568 * Create a new session. Also queues a welcome message.
571 * @param target peer to connect to
572 * @param client client to use
573 * @param is_nat this a NAT session, we should wait for a client to
574 * connect to us from an address, then assign that to
576 * @return new session object
578 static struct Session *
579 create_session (struct Plugin *plugin,
580 const struct GNUNET_PeerIdentity *target,
581 struct GNUNET_SERVER_Client *client, int is_nat)
584 struct PendingMessage *pm;
585 struct WelcomeMessage welcome;
587 if (is_nat != GNUNET_YES)
588 GNUNET_assert (client != NULL);
590 GNUNET_assert (client == NULL);
593 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
594 "Creating new session for peer `%4s'\n",
595 GNUNET_i2s (target));
597 ret = GNUNET_malloc (sizeof (struct Session));
598 ret->last_activity = GNUNET_TIME_absolute_get ();
599 ret->plugin = plugin;
600 ret->is_nat = is_nat;
601 if (is_nat != GNUNET_YES) /* If not a NAT WAIT conn, add it to global list */
603 ret->next = plugin->sessions;
604 plugin->sessions = ret;
606 ret->client = client;
607 ret->target = *target;
608 ret->expecting_welcome = GNUNET_YES;
609 pm = GNUNET_malloc (sizeof (struct PendingMessage) + sizeof (struct WelcomeMessage));
610 pm->msg = (const char*) &pm[1];
611 pm->message_size = sizeof (struct WelcomeMessage);
612 welcome.header.size = htons (sizeof (struct WelcomeMessage));
613 welcome.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME);
614 welcome.clientIdentity = *plugin->env->my_identity;
615 memcpy (&pm[1], &welcome, sizeof (welcome));
616 pm->timeout = GNUNET_TIME_UNIT_FOREVER_ABS;
617 GNUNET_STATISTICS_update (plugin->env->stats,
618 gettext_noop ("# bytes currently in TCP buffers"),
621 GNUNET_CONTAINER_DLL_insert (ret->pending_messages_head,
622 ret->pending_messages_tail,
624 if (is_nat != GNUNET_YES)
625 GNUNET_STATISTICS_update (plugin->env->stats,
626 gettext_noop ("# TCP sessions active"),
634 * If we have pending messages, ask the server to
635 * transmit them (schedule the respective tasks, etc.)
637 * @param session for which session should we do this
639 static void process_pending_messages (struct Session *session);
643 * Function called to notify a client about the socket
644 * being ready to queue more data. "buf" will be
645 * NULL and "size" zero if the socket was closed for
646 * writing in the meantime.
649 * @param size number of bytes available in buf
650 * @param buf where the callee should write the message
651 * @return number of bytes written to buf
654 do_transmit (void *cls, size_t size, void *buf)
656 struct Session *session = cls;
657 struct GNUNET_PeerIdentity pid;
658 struct Plugin *plugin;
659 struct PendingMessage *pos;
660 struct PendingMessage *hd;
661 struct PendingMessage *tl;
662 struct GNUNET_TIME_Absolute now;
666 session->transmit_handle = NULL;
667 plugin = session->plugin;
671 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
672 "Timeout trying to transmit to peer `%4s', discarding message queue.\n",
673 GNUNET_i2s (&session->target));
675 /* timeout; cancel all messages that have already expired */
679 now = GNUNET_TIME_absolute_get ();
680 while ( (NULL != (pos = session->pending_messages_head)) &&
681 (pos->timeout.value <= now.value) )
683 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
684 session->pending_messages_tail,
687 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
688 "Failed to transmit %u byte message to `%4s'.\n",
690 GNUNET_i2s (&session->target));
692 ret += pos->message_size;
693 GNUNET_CONTAINER_DLL_insert_after (hd, tl, tl, pos);
695 /* do this call before callbacks (so that if callbacks destroy
696 session, they have a chance to cancel actions done by this
698 process_pending_messages (session);
699 pid = session->target;
700 /* no do callbacks and do not use session again since
701 the callbacks may abort the session */
702 while (NULL != (pos = hd))
704 GNUNET_CONTAINER_DLL_remove (hd, tl, pos);
705 if (pos->transmit_cont != NULL)
706 pos->transmit_cont (pos->transmit_cont_cls,
707 &pid, GNUNET_SYSERR);
710 GNUNET_STATISTICS_update (plugin->env->stats,
711 gettext_noop ("# bytes currently in TCP buffers"),
714 GNUNET_STATISTICS_update (plugin->env->stats,
715 gettext_noop ("# bytes discarded by TCP (timeout)"),
720 /* copy all pending messages that would fit */
725 while (NULL != (pos = session->pending_messages_head))
727 if (ret + pos->message_size > size)
729 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
730 session->pending_messages_tail,
732 GNUNET_assert (size >= pos->message_size);
733 /* FIXME: this memcpy can be up to 7% of our total runtime */
734 memcpy (cbuf, pos->msg, pos->message_size);
735 cbuf += pos->message_size;
736 ret += pos->message_size;
737 size -= pos->message_size;
738 GNUNET_CONTAINER_DLL_insert_after (hd, tl, tl, pos);
740 /* schedule 'continuation' before callbacks so that callbacks that
741 cancel everything don't cause us to use a session that no longer
743 process_pending_messages (session);
744 session->last_activity = GNUNET_TIME_absolute_get ();
745 pid = session->target;
746 /* we'll now call callbacks that may cancel the session; hence
747 we should not use 'session' after this point */
748 while (NULL != (pos = hd))
750 GNUNET_CONTAINER_DLL_remove (hd, tl, pos);
751 if (pos->transmit_cont != NULL)
752 pos->transmit_cont (pos->transmit_cont_cls,
756 GNUNET_assert (hd == NULL);
757 GNUNET_assert (tl == NULL);
759 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
760 "Transmitting %u bytes\n", ret);
762 GNUNET_STATISTICS_update (plugin->env->stats,
763 gettext_noop ("# bytes currently in TCP buffers"),
766 GNUNET_STATISTICS_update (plugin->env->stats,
767 gettext_noop ("# bytes transmitted via TCP"),
775 * If we have pending messages, ask the server to
776 * transmit them (schedule the respective tasks, etc.)
778 * @param session for which session should we do this
781 process_pending_messages (struct Session *session)
783 struct PendingMessage *pm;
785 GNUNET_assert (session->client != NULL);
786 if (session->transmit_handle != NULL)
788 if (NULL == (pm = session->pending_messages_head))
791 session->transmit_handle
792 = GNUNET_SERVER_notify_transmit_ready (session->client,
794 GNUNET_TIME_absolute_get_remaining
796 &do_transmit, session);
801 * Functions with this signature are called whenever we need
802 * to close a session due to a disconnect or failure to
803 * establish a connection.
805 * @param session session to close down
808 disconnect_session (struct Session *session)
810 struct Session *prev;
812 struct PendingMessage *pm;
815 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
816 "Disconnecting from `%4s' at %s (session %p).\n",
817 GNUNET_i2s (&session->target),
818 (session->connect_addr != NULL) ?
819 tcp_address_to_string (session->plugin,
820 session->connect_addr,
821 session->connect_alen) : "*",
824 /* remove from session list */
826 pos = session->plugin->sessions;
827 while (pos != session)
833 session->plugin->sessions = session->next;
835 prev->next = session->next;
836 session->plugin->env->session_end (session->plugin->env->cls,
840 if (session->transmit_handle != NULL)
842 GNUNET_CONNECTION_notify_transmit_ready_cancel
843 (session->transmit_handle);
844 session->transmit_handle = NULL;
846 while (NULL != (pm = session->pending_messages_head))
849 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
851 pm->transmit_cont != NULL
852 ? "Could not deliver message to `%4s'.\n"
854 "Could not deliver message to `%4s', notifying.\n",
855 GNUNET_i2s (&session->target));
857 GNUNET_STATISTICS_update (session->plugin->env->stats,
858 gettext_noop ("# bytes currently in TCP buffers"),
859 - (int64_t) pm->message_size,
861 GNUNET_STATISTICS_update (session->plugin->env->stats,
862 gettext_noop ("# bytes discarded by TCP (disconnect)"),
865 GNUNET_CONTAINER_DLL_remove (session->pending_messages_head,
866 session->pending_messages_tail,
868 if (NULL != pm->transmit_cont)
869 pm->transmit_cont (pm->transmit_cont_cls,
870 &session->target, GNUNET_SYSERR);
873 GNUNET_break (session->client != NULL);
874 if (session->receive_delay_task != GNUNET_SCHEDULER_NO_TASK)
876 GNUNET_SCHEDULER_cancel (session->plugin->env->sched,
877 session->receive_delay_task);
878 if (session->client != NULL)
879 GNUNET_SERVER_receive_done (session->client,
882 if (session->client != NULL)
883 GNUNET_SERVER_client_drop (session->client);
884 GNUNET_STATISTICS_update (session->plugin->env->stats,
885 gettext_noop ("# TCP sessions active"),
888 GNUNET_free_non_null (session->connect_addr);
889 GNUNET_free (session);
894 * Given two otherwise equivalent sessions, pick the better one.
896 * @param s1 one session (also default)
897 * @param s2 other session
898 * @return "better" session (more active)
900 static struct Session *
901 select_better_session (struct Session *s1,
908 if ( (s1->expecting_welcome == GNUNET_NO) &&
909 (s2->expecting_welcome == GNUNET_YES) )
911 if ( (s1->expecting_welcome == GNUNET_YES) &&
912 (s2->expecting_welcome == GNUNET_NO) )
914 if (s1->last_activity.value < s2->last_activity.value)
916 if (s1->last_activity.value > s2->last_activity.value)
918 if ( (GNUNET_YES == s1->inbound) &&
919 (GNUNET_NO == s2->inbound) )
921 if ( (GNUNET_NO == s1->inbound) &&
922 (GNUNET_YES == s2->inbound) )
929 * We learned about a peer (possibly behind NAT) so run the
930 * gnunet-nat-client to send dummy ICMP responses
932 * @param plugin the plugin for this transport
933 * @param addr the address of the peer
934 * @param addrlen the length of the address
937 run_gnunet_nat_client (struct Plugin *plugin, const char *addr, size_t addrlen)
939 char inet4[INET_ADDRSTRLEN];
940 char *address_as_string;
941 char *port_as_string;
943 const struct sockaddr *sa = (const struct sockaddr *)addr;
946 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
947 _("called run_gnunet_nat_client addrlen %d others are %d and %d\n"), addrlen, sizeof (struct sockaddr), sizeof (struct sockaddr_in));
950 if (addrlen < sizeof (struct sockaddr))
953 switch (sa->sa_family)
956 if (addrlen != sizeof (struct sockaddr_in))
958 if (NULL == inet_ntop (AF_INET,
959 &((struct sockaddr_in *) sa)->sin_addr,
960 inet4, INET_ADDRSTRLEN))
962 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
965 address_as_string = GNUNET_strdup (inet4);
972 GNUNET_asprintf(&port_as_string, "%d", plugin->adv_port);
974 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
975 _("Running gnunet-nat-client with arguments: %s %s %d\n"), plugin->external_address, address_as_string, plugin->adv_port);
978 /* Start the client process */
979 pid = GNUNET_OS_start_process(NULL, NULL, "gnunet-nat-client", "gnunet-nat-client", plugin->external_address, address_as_string, port_as_string, NULL);
980 GNUNET_free(address_as_string);
981 GNUNET_free(port_as_string);
982 GNUNET_OS_process_wait (pid);
987 * Function that can be used by the transport service to transmit
988 * a message using the plugin. Note that in the case of a
989 * peer disconnecting, the continuation MUST be called
990 * prior to the disconnect notification itself. This function
991 * will be called with this peer's HELLO message to initiate
992 * a fresh connection to another peer.
995 * @param target who should receive this message
996 * @param msg the message to transmit
997 * @param msgbuf_size number of bytes in 'msg'
998 * @param priority how important is the message (most plugins will
999 * ignore message priority and just FIFO)
1000 * @param timeout how long to wait at most for the transmission (does not
1001 * require plugins to discard the message after the timeout,
1002 * just advisory for the desired delay; most plugins will ignore
1004 * @param session which session must be used (or NULL for "any")
1005 * @param addr the address to use (can be NULL if the plugin
1006 * is "on its own" (i.e. re-use existing TCP connection))
1007 * @param addrlen length of the address in bytes
1008 * @param force_address GNUNET_YES if the plugin MUST use the given address,
1009 * GNUNET_NO means the plugin may use any other address and
1010 * GNUNET_SYSERR means that only reliable existing
1011 * bi-directional connections should be used (regardless
1013 * @param cont continuation to call once the message has
1014 * been transmitted (or if the transport is ready
1015 * for the next transmission call; or if the
1016 * peer disconnected...); can be NULL
1017 * @param cont_cls closure for cont
1018 * @return number of bytes used (on the physical network, with overheads);
1019 * -1 on hard errors (i.e. address invalid); 0 is a legal value
1020 * and does NOT mean that the message was not transmitted (DV and NAT)
1023 tcp_plugin_send (void *cls,
1024 const struct GNUNET_PeerIdentity *target,
1028 struct GNUNET_TIME_Relative timeout,
1029 struct Session *session,
1033 GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
1035 struct Plugin *plugin = cls;
1036 struct Session *cand_session;
1037 struct Session *next;
1038 struct PendingMessage *pm;
1039 struct GNUNET_CONNECTION_Handle *sa;
1043 struct sockaddr_in a4;
1044 struct sockaddr_in6 a6;
1045 const struct IPv4TcpAddress *t4;
1046 const struct IPv6TcpAddress *t6;
1047 unsigned int is_natd;
1049 GNUNET_STATISTICS_update (plugin->env->stats,
1050 gettext_noop ("# bytes TCP was asked to transmit"),
1053 /* FIXME: we could do this cheaper with a hash table
1054 where we could restrict the iteration to entries that match
1055 the target peer... */
1056 is_natd = GNUNET_NO;
1057 if (session == NULL)
1059 cand_session = NULL;
1060 next = plugin->sessions;
1061 while (NULL != (session = next))
1063 next = session->next;
1064 GNUNET_assert (session->client != NULL);
1065 if (0 != memcmp (target,
1067 sizeof (struct GNUNET_PeerIdentity)))
1069 if ( ( (GNUNET_SYSERR == force_address) &&
1070 (session->expecting_welcome == GNUNET_NO) ) ||
1071 (GNUNET_NO == force_address) )
1073 cand_session = select_better_session (cand_session,
1077 if (GNUNET_SYSERR == force_address)
1079 GNUNET_break (GNUNET_YES == force_address);
1085 if (session->inbound == GNUNET_YES)
1087 if ((addrlen != session->connect_alen) && (session->is_nat == GNUNET_NO))
1089 if ((0 != memcmp (session->connect_addr,
1091 addrlen)) && (session->is_nat == GNUNET_NO))
1093 cand_session = select_better_session (cand_session,
1096 session = cand_session;
1098 if ( (session == NULL) &&
1102 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1103 "Asked to transmit to `%4s' without address and I have no existing connection (failing).\n",
1104 GNUNET_i2s (target));
1106 GNUNET_STATISTICS_update (plugin->env->stats,
1107 gettext_noop ("# bytes discarded by TCP (no address and no connection)"),
1112 if (session == NULL)
1114 if (addrlen == sizeof (struct IPv6TcpAddress))
1118 memset (&a6, 0, sizeof (a6));
1119 #if HAVE_SOCKADDR_IN_SIN_LEN
1120 a6.sin6_len = sizeof (a6);
1122 a6.sin6_family = AF_INET6;
1123 a6.sin6_port = t6->t6_port;
1124 if (t6->t6_port == 0)
1125 is_natd = GNUNET_YES;
1126 memcpy (&a6.sin6_addr,
1128 sizeof (struct in6_addr));
1132 else if (addrlen == sizeof (struct IPv4TcpAddress))
1136 memset (&a4, 0, sizeof (a4));
1137 #if HAVE_SOCKADDR_IN_SIN_LEN
1138 a4.sin_len = sizeof (a4);
1140 a4.sin_family = AF_INET;
1141 a4.sin_port = t4->t_port;
1142 if (t4->t_port == 0)
1143 is_natd = GNUNET_YES;
1144 a4.sin_addr.s_addr = t4->ipv4_addr;
1150 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1151 _("Address of unexpected length: %u\n"),
1157 if ((is_natd == GNUNET_YES) && (addrlen == sizeof (struct IPv6TcpAddress)))
1158 return -1; /* NAT client only works with IPv4 addresses */
1161 if ((plugin->allow_nat == GNUNET_YES) && (is_natd == GNUNET_YES) &&
1162 (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns, &target->hashPubKey)))
1165 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1166 _("Found valid IPv4 NAT address!\n"));
1168 session = create_session (plugin,
1172 /* create new message entry */
1173 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msgbuf_size);
1174 /* FIXME: the memset of this malloc can be up to 2% of our total runtime */
1175 pm->msg = (const char*) &pm[1];
1176 memcpy (&pm[1], msg, msgbuf_size);
1177 /* FIXME: this memcpy can be up to 7% of our total run-time
1178 (for transport service) */
1179 pm->message_size = msgbuf_size;
1180 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1181 pm->transmit_cont = cont;
1182 pm->transmit_cont_cls = cont_cls;
1184 /* append pm to pending_messages list */
1185 GNUNET_CONTAINER_DLL_insert_after (session->pending_messages_head,
1186 session->pending_messages_tail,
1187 session->pending_messages_tail,
1190 GNUNET_assert(GNUNET_CONTAINER_multihashmap_put(plugin->nat_wait_conns, &target->hashPubKey, session, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY) == GNUNET_OK);
1192 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1193 "Created NAT WAIT connection to `%4s' at `%s'\n",
1194 GNUNET_i2s (target),
1195 GNUNET_a2s (sb, sbs));
1197 run_gnunet_nat_client (plugin, sb, sbs);
1200 else if ((plugin->allow_nat == GNUNET_YES) && (is_natd == GNUNET_YES) && (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns, &target->hashPubKey)))
1202 /* Only do one NAT punch attempt per peer identity */
1205 sa = GNUNET_CONNECTION_create_from_sockaddr (plugin->env->sched,
1210 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1211 "Failed to create connection to `%4s' at `%s'\n",
1212 GNUNET_i2s (target),
1213 GNUNET_a2s (sb, sbs));
1215 GNUNET_STATISTICS_update (plugin->env->stats,
1216 gettext_noop ("# bytes discarded by TCP (failed to connect)"),
1222 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1223 "Asked to transmit to `%4s', creating fresh session using address `%s'.\n",
1224 GNUNET_i2s (target),
1225 GNUNET_a2s (sb, sbs));
1227 session = create_session (plugin,
1229 GNUNET_SERVER_connect_socket (plugin->server,
1231 session->connect_addr = GNUNET_malloc (addrlen);
1232 memcpy (session->connect_addr,
1235 session->connect_alen = addrlen;
1237 GNUNET_assert (session != NULL);
1238 GNUNET_assert (session->client != NULL);
1239 GNUNET_STATISTICS_update (plugin->env->stats,
1240 gettext_noop ("# bytes currently in TCP buffers"),
1243 /* create new message entry */
1244 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msgbuf_size);
1245 pm->msg = (const char*) &pm[1];
1246 memcpy (&pm[1], msg, msgbuf_size);
1247 pm->message_size = msgbuf_size;
1248 pm->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1249 pm->transmit_cont = cont;
1250 pm->transmit_cont_cls = cont_cls;
1252 /* append pm to pending_messages list */
1253 GNUNET_CONTAINER_DLL_insert_after (session->pending_messages_head,
1254 session->pending_messages_tail,
1255 session->pending_messages_tail,
1258 GNUNET_log (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 (GNUNET_ERROR_TYPE_DEBUG,
1295 "Asked to cancel session with `%4s'\n",
1296 GNUNET_i2s (target));
1298 next = plugin->sessions;
1299 while (NULL != (session = next))
1301 next = session->next;
1302 if (0 != memcmp (target,
1304 sizeof (struct GNUNET_PeerIdentity)))
1306 pm = session->pending_messages_head;
1309 pm->transmit_cont = NULL;
1310 pm->transmit_cont_cls = NULL;
1313 disconnect_session (session);
1319 * Context for address to string conversion.
1321 struct PrettyPrinterContext
1324 * Function to call with the result.
1326 GNUNET_TRANSPORT_AddressStringCallback asc;
1329 * Clsoure for 'asc'.
1334 * Port to add after the IP address.
1341 * Append our port and forward the result.
1343 * @param cls the 'struct PrettyPrinterContext*'
1344 * @param hostname hostname part of the address
1347 append_port (void *cls, const char *hostname)
1349 struct PrettyPrinterContext *ppc = cls;
1352 if (hostname == NULL)
1354 ppc->asc (ppc->asc_cls, NULL);
1358 GNUNET_asprintf (&ret, "%s:%d", hostname, ppc->port);
1359 ppc->asc (ppc->asc_cls, ret);
1365 * Convert the transports address to a nice, human-readable
1368 * @param cls closure
1369 * @param type name of the transport that generated the address
1370 * @param addr one of the addresses of the host, NULL for the last address
1371 * the specific address format depends on the transport
1372 * @param addrlen length of the address
1373 * @param numeric should (IP) addresses be displayed in numeric form?
1374 * @param timeout after how long should we give up?
1375 * @param asc function to call on each string
1376 * @param asc_cls closure for asc
1379 tcp_plugin_address_pretty_printer (void *cls,
1384 struct GNUNET_TIME_Relative timeout,
1385 GNUNET_TRANSPORT_AddressStringCallback asc,
1388 struct Plugin *plugin = cls;
1389 struct PrettyPrinterContext *ppc;
1392 struct sockaddr_in a4;
1393 struct sockaddr_in6 a6;
1394 const struct IPv4TcpAddress *t4;
1395 const struct IPv6TcpAddress *t6;
1398 if (addrlen == sizeof (struct IPv6TcpAddress))
1401 memset (&a6, 0, sizeof (a6));
1402 a6.sin6_family = AF_INET6;
1403 a6.sin6_port = t6->t6_port;
1404 memcpy (&a6.sin6_addr,
1406 sizeof (struct in6_addr));
1407 port = ntohs (t6->t6_port);
1411 else if (addrlen == sizeof (struct IPv4TcpAddress))
1414 memset (&a4, 0, sizeof (a4));
1415 a4.sin_family = AF_INET;
1416 a4.sin_port = t4->t_port;
1417 a4.sin_addr.s_addr = t4->ipv4_addr;
1418 port = ntohs (t4->t_port);
1424 /* invalid address */
1425 GNUNET_break_op (0);
1426 asc (asc_cls, NULL);
1429 ppc = GNUNET_malloc (sizeof (struct PrettyPrinterContext));
1431 ppc->asc_cls = asc_cls;
1433 GNUNET_RESOLVER_hostname_get (plugin->env->sched,
1437 !numeric, timeout, &append_port, ppc);
1442 * Check if the given port is plausible (must be either
1443 * our listen port or our advertised port). If it is
1444 * neither, we return GNUNET_SYSERR.
1446 * @param plugin global variables
1447 * @param in_port port number to check
1448 * @return GNUNET_OK if port is either open_port or adv_port
1451 check_port (struct Plugin *plugin, uint16_t in_port)
1453 if ( (plugin->behind_nat == GNUNET_YES) && (in_port == 0) )
1455 if ( (plugin->only_nat_addresses == GNUNET_YES) &&
1456 (plugin->behind_nat == GNUNET_YES) )
1458 return GNUNET_SYSERR; /* odd case... */
1460 if ((in_port == plugin->adv_port) || (in_port == plugin->open_port))
1462 return GNUNET_SYSERR;
1467 * Function that will be called to check if a binary address for this
1468 * plugin is well-formed and corresponds to an address for THIS peer
1469 * (as per our configuration). Naturally, if absolutely necessary,
1470 * plugins can be a bit conservative in their answer, but in general
1471 * plugins should make sure that the address does not redirect
1472 * traffic to a 3rd party that might try to man-in-the-middle our
1475 * @param cls closure, our 'struct Plugin*'
1476 * @param addr pointer to the address
1477 * @param addrlen length of addr
1478 * @return GNUNET_OK if this is a plausible address for this peer
1479 * and transport, GNUNET_SYSERR if not
1482 tcp_plugin_check_address (void *cls,
1486 struct Plugin *plugin = cls;
1487 struct IPv4TcpAddress *v4;
1488 struct IPv6TcpAddress *v6;
1490 if ((addrlen != sizeof (struct IPv4TcpAddress)) &&
1491 (addrlen != sizeof (struct IPv6TcpAddress)))
1493 GNUNET_break_op (0);
1494 return GNUNET_SYSERR;
1496 if (addrlen == sizeof (struct IPv4TcpAddress))
1498 v4 = (struct IPv4TcpAddress *) addr;
1500 check_port (plugin, ntohs (v4->t_port)))
1501 return GNUNET_SYSERR;
1503 check_local_addr (plugin, &v4->ipv4_addr, sizeof (uint32_t)))
1505 return GNUNET_SYSERR;
1510 v6 = (struct IPv6TcpAddress *) addr;
1511 if (IN6_IS_ADDR_LINKLOCAL (&v6->ipv6_addr))
1513 GNUNET_break_op (0);
1514 return GNUNET_SYSERR;
1517 check_port (plugin, ntohs (v6->t6_port)))
1518 return GNUNET_SYSERR;
1520 check_local_addr (plugin, &v6->ipv6_addr, sizeof (struct in6_addr)))
1522 return GNUNET_SYSERR;
1529 * We've received a nat probe from this peer via TCP. Finish
1530 * creating the client session and resume sending of queued
1533 * @param cls closure
1534 * @param client identification of the client
1535 * @param message the actual message
1538 handle_tcp_nat_probe (void *cls,
1539 struct GNUNET_SERVER_Client *client,
1540 const struct GNUNET_MessageHeader *message)
1542 struct Plugin *plugin = cls;
1543 struct Session *session;
1544 struct TCP_NAT_ProbeMessage *tcp_nat_probe;
1547 struct IPv4TcpAddress *t4;
1548 struct IPv6TcpAddress *t6;
1549 const struct sockaddr_in *s4;
1550 const struct sockaddr_in6 *s6;
1553 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "received tcp NAT probe\n");
1555 /* We have received a TCP NAT probe, meaning we (hopefully) initiated
1556 * a connection to this peer by running gnunet-nat-client. This peer
1557 * received the punch message and now wants us to use the new connection
1558 * as the default for that peer. Do so and then send a WELCOME message
1559 * so we can really be connected!
1561 if (ntohs(message->size) != sizeof(struct TCP_NAT_ProbeMessage))
1564 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));
1569 tcp_nat_probe = (struct TCP_NAT_ProbeMessage *)message;
1571 if (GNUNET_CONTAINER_multihashmap_contains(plugin->nat_wait_conns, &tcp_nat_probe->clientIdentity.hashPubKey) == GNUNET_YES)
1574 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Found session for NAT probe!\n");
1576 session = GNUNET_CONTAINER_multihashmap_get(plugin->nat_wait_conns, &tcp_nat_probe->clientIdentity.hashPubKey);
1577 GNUNET_assert(session != NULL);
1578 GNUNET_assert(GNUNET_CONTAINER_multihashmap_remove(plugin->nat_wait_conns, &tcp_nat_probe->clientIdentity.hashPubKey, session) == GNUNET_YES);
1579 GNUNET_SERVER_client_keep (client);
1580 session->client = client;
1581 session->last_activity = GNUNET_TIME_absolute_get ();
1582 session->inbound = GNUNET_NO;
1585 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1588 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1589 "Found address `%s' for incoming connection %p\n",
1590 GNUNET_a2s (vaddr, alen),
1593 if (((const struct sockaddr *)vaddr)->sa_family == AF_INET)
1596 t4 = GNUNET_malloc (sizeof (struct IPv4TcpAddress));
1597 t4->t_port = s4->sin_port;
1598 t4->ipv4_addr = s4->sin_addr.s_addr;
1599 session->connect_addr = t4;
1600 session->connect_alen = sizeof (struct IPv4TcpAddress);
1602 else if (((const struct sockaddr *)vaddr)->sa_family == AF_INET6)
1605 t6 = GNUNET_malloc (sizeof (struct IPv6TcpAddress));
1606 t6->t6_port = s6->sin6_port;
1607 memcpy (&t6->ipv6_addr,
1609 sizeof (struct in6_addr));
1610 session->connect_addr = t6;
1611 session->connect_alen = sizeof (struct IPv6TcpAddress);
1616 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1617 "Bad address for incoming connection!\n");
1620 GNUNET_free (vaddr);
1623 session->next = plugin->sessions;
1624 plugin->sessions = session;
1625 GNUNET_STATISTICS_update (plugin->env->stats,
1626 gettext_noop ("# TCP sessions active"),
1629 process_pending_messages (session);
1634 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Did NOT find session for NAT probe!\n");
1638 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1642 * We've received a welcome from this peer via TCP. Possibly create a
1643 * fresh client record and send back our welcome.
1645 * @param cls closure
1646 * @param client identification of the client
1647 * @param message the actual message
1650 handle_tcp_welcome (void *cls,
1651 struct GNUNET_SERVER_Client *client,
1652 const struct GNUNET_MessageHeader *message)
1654 struct Plugin *plugin = cls;
1655 const struct WelcomeMessage *wm = (const struct WelcomeMessage *) message;
1656 struct Session *session;
1659 struct IPv4TcpAddress *t4;
1660 struct IPv6TcpAddress *t6;
1661 const struct sockaddr_in *s4;
1662 const struct sockaddr_in6 *s6;
1665 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1666 "Received %s message from a `%4s/%p'.\n",
1668 GNUNET_i2s (&wm->clientIdentity), client);
1670 GNUNET_STATISTICS_update (plugin->env->stats,
1671 gettext_noop ("# TCP WELCOME messages received"),
1674 session = find_session_by_client (plugin, client);
1675 if (session == NULL)
1677 GNUNET_SERVER_client_keep (client);
1678 session = create_session (plugin,
1679 &wm->clientIdentity, client, GNUNET_NO);
1680 session->inbound = GNUNET_YES;
1682 GNUNET_SERVER_client_get_address (client, &vaddr, &alen))
1685 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1686 "Found address `%s' for incoming connection %p\n",
1687 GNUNET_a2s (vaddr, alen),
1690 if (alen == sizeof (struct sockaddr_in))
1693 t4 = GNUNET_malloc (sizeof (struct IPv4TcpAddress));
1694 t4->t_port = s4->sin_port;
1695 t4->ipv4_addr = s4->sin_addr.s_addr;
1696 session->connect_addr = t4;
1697 session->connect_alen = sizeof (struct IPv4TcpAddress);
1699 else if (alen == sizeof (struct sockaddr_in6))
1702 t6 = GNUNET_malloc (sizeof (struct IPv6TcpAddress));
1703 t6->t6_port = s6->sin6_port;
1704 memcpy (&t6->ipv6_addr,
1706 sizeof (struct in6_addr));
1707 session->connect_addr = t6;
1708 session->connect_alen = sizeof (struct IPv6TcpAddress);
1710 GNUNET_free (vaddr);
1715 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1716 "Did not obtain TCP socket address for incoming connection\n");
1720 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1721 "Creating new session %p for connection %p\n",
1724 process_pending_messages (session);
1726 if (session->expecting_welcome != GNUNET_YES)
1728 GNUNET_break_op (0);
1729 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1732 session->last_activity = GNUNET_TIME_absolute_get ();
1733 session->expecting_welcome = GNUNET_NO;
1734 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1739 * Task to signal the server that we can continue
1740 * receiving from the TCP client now.
1742 * @param cls the 'struct Session*'
1743 * @param tc task context (unused)
1746 delayed_done (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1748 struct Session *session = cls;
1749 struct GNUNET_TIME_Relative delay;
1751 session->receive_delay_task = GNUNET_SCHEDULER_NO_TASK;
1752 delay = session->plugin->env->receive (session->plugin->env->cls,
1757 if (delay.value == 0)
1758 GNUNET_SERVER_receive_done (session->client, GNUNET_OK);
1760 session->receive_delay_task =
1761 GNUNET_SCHEDULER_add_delayed (session->plugin->env->sched,
1762 delay, &delayed_done, session);
1767 * We've received data for this peer via TCP. Unbox,
1768 * compute latency and forward.
1770 * @param cls closure
1771 * @param client identification of the client
1772 * @param message the actual message
1775 handle_tcp_data (void *cls,
1776 struct GNUNET_SERVER_Client *client,
1777 const struct GNUNET_MessageHeader *message)
1779 struct Plugin *plugin = cls;
1780 struct Session *session;
1781 struct GNUNET_TIME_Relative delay;
1783 if ((GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME == ntohs(message->type)) || (ntohs(message->type) == GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE))
1785 /* We don't want to propagate WELCOME and NAT Probe messages up! */
1786 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1789 session = find_session_by_client (plugin, client);
1790 if ( (NULL == session) || (GNUNET_YES == session->expecting_welcome))
1792 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1795 session->last_activity = GNUNET_TIME_absolute_get ();
1797 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1798 "Passing %u bytes of type %u from `%4s' to transport service.\n",
1799 (unsigned int) ntohs (message->size),
1800 (unsigned int) ntohs (message->type),
1801 GNUNET_i2s (&session->target));
1803 GNUNET_STATISTICS_update (plugin->env->stats,
1804 gettext_noop ("# bytes received via TCP"),
1805 ntohs (message->size),
1807 delay = plugin->env->receive (plugin->env->cls, &session->target, message, 1,
1809 (GNUNET_YES == session->inbound) ? NULL : session->connect_addr,
1810 (GNUNET_YES == session->inbound) ? 0 : session->connect_alen);
1811 if (delay.value == 0)
1812 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1814 session->receive_delay_task =
1815 GNUNET_SCHEDULER_add_delayed (session->plugin->env->sched,
1816 delay, &delayed_done, session);
1821 * Functions with this signature are called whenever a peer
1822 * is disconnected on the network level.
1824 * @param cls closure
1825 * @param client identification of the client
1828 disconnect_notify (void *cls,
1829 struct GNUNET_SERVER_Client *client)
1831 struct Plugin *plugin = cls;
1832 struct Session *session;
1836 session = find_session_by_client (plugin, client);
1837 if (session == NULL)
1838 return; /* unknown, nothing to do */
1840 GNUNET_log (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;
1879 char buf[INET_ADDRSTRLEN];
1881 af = addr->sa_family;
1885 t4.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
1886 GNUNET_assert(NULL != inet_ntop(AF_INET, &t4.ipv4_addr, &buf[0], INET_ADDRSTRLEN));
1887 if ((plugin->bind_address != NULL) && (0 != strcmp(buf, plugin->bind_address)))
1889 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "%s: Not notifying transport of address %s\n", "TCP", GNUNET_a2s (addr, addrlen));
1892 add_to_address_list (plugin, &t4.ipv4_addr, sizeof (uint32_t));
1893 if ((plugin->behind_nat == GNUNET_YES) && (plugin->only_nat_addresses == GNUNET_YES))
1894 t4.t_port = htons(0);
1895 else if (plugin->behind_nat == GNUNET_YES) /* We are behind NAT, but will advertise NAT and normal addresses */
1897 t4_nat.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
1898 t4_nat.t_port = htons(plugin->adv_port);
1902 t4.t_port = htons (plugin->adv_port);
1906 else if (af == AF_INET6)
1908 if ((IN6_IS_ADDR_LINKLOCAL (&((struct sockaddr_in6 *) addr)->sin6_addr)) || (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno(plugin->env->cfg, "transport-tcp", "disablev6")))
1910 /* skip link local addresses */
1913 memcpy (&t6.ipv6_addr,
1914 &((struct sockaddr_in6 *) addr)->sin6_addr,
1915 sizeof (struct in6_addr));
1916 add_to_address_list (plugin, &t6.ipv6_addr, sizeof (struct in6_addr));
1917 if ((plugin->behind_nat == GNUNET_YES) && (plugin->only_nat_addresses == GNUNET_YES))
1918 t6.t6_port = htons(0);
1919 else if (plugin->behind_nat == GNUNET_YES) /* We are behind NAT, but will advertise NAT and normal addresses */
1921 memcpy (&t6_nat.ipv6_addr,
1922 &((struct sockaddr_in6 *) addr)->sin6_addr,
1923 sizeof (struct in6_addr));
1924 t6_nat.t6_port = htons(plugin->adv_port);
1928 t6.t6_port = htons (plugin->adv_port);
1937 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1938 _("Found address `%s' (%s) len %d\n"),
1939 GNUNET_a2s (addr, addrlen), name, args);
1941 plugin->env->notify_address (plugin->env->cls,
1943 arg, args, GNUNET_TIME_UNIT_FOREVER_REL);
1945 if (arg_nat != NULL)
1947 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1948 _("Found address `%s' (%s) len %d\n"),
1949 GNUNET_a2s (addr, addrlen), name, args);
1950 plugin->env->notify_address (plugin->env->cls,
1952 arg_nat, args, GNUNET_TIME_UNIT_FOREVER_REL);
1960 * Function called by the resolver for each address obtained from DNS
1961 * for our own hostname. Add the addresses to the list of our
1962 * external IP addresses.
1964 * @param cls closure
1965 * @param addr one of the addresses of the host, NULL for the last address
1966 * @param addrlen length of the address
1969 process_hostname_ips (void *cls,
1970 const struct sockaddr *addr, socklen_t addrlen)
1972 struct Plugin *plugin = cls;
1976 plugin->hostname_dns = NULL;
1979 /* FIXME: Can we figure out our external address here so it doesn't need to be user specified? */
1980 process_interfaces (plugin, "<hostname>", GNUNET_YES, addr, addrlen);
1984 * We can now send a probe message, copy into buffer to really send.
1986 * @param cls closure, a struct TCPProbeContext
1987 * @param size max size to copy
1988 * @param buf buffer to copy message to
1990 static size_t notify_send_probe (void *cls,
1991 size_t size, void *buf)
1993 struct TCPProbeContext *tcp_probe_ctx = cls;
2000 GNUNET_assert(size >= sizeof(tcp_probe_ctx->message));
2001 memcpy(buf, &tcp_probe_ctx->message, sizeof(tcp_probe_ctx->message));
2002 GNUNET_SERVER_connect_socket (tcp_probe_ctx->plugin->server,
2003 tcp_probe_ctx->sock);
2005 GNUNET_free(tcp_probe_ctx);
2006 return sizeof(tcp_probe_ctx->message);
2010 * @param cls the plugin handle
2011 * @param tc the scheduling context (for rescheduling this function again)
2013 * We have been notified that gnunet-nat-server has written something to stdout.
2014 * Handle the output, then reschedule this function to be called again once
2015 * more is available.
2019 tcp_plugin_server_read (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
2021 struct Plugin *plugin = cls;
2024 memset(&mybuf, 0, sizeof(mybuf));
2028 struct sockaddr_in in_addr;
2029 struct TCPProbeContext *tcp_probe_ctx;
2030 struct GNUNET_CONNECTION_Handle *sock;
2032 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
2035 bytes = GNUNET_DISK_file_read(plugin->server_stdout_handle, &mybuf, sizeof(mybuf));
2040 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2041 _("Finished reading from server stdout with code: %d\n"), bytes);
2047 for (i = 0; i < sizeof(mybuf); i++)
2049 if (mybuf[i] == '\n')
2052 if ((mybuf[i] == ':') && (i + 1 < sizeof(mybuf)))
2055 port_start = &mybuf[i + 1];
2059 if (port_start != NULL)
2060 port = atoi(port_start);
2063 plugin->server_read_task =
2064 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2065 GNUNET_TIME_UNIT_FOREVER_REL,
2066 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2071 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2072 _("nat-server-read read: %s port %d\n"), &mybuf, port);
2076 if (inet_pton(AF_INET, &mybuf[0], &in_addr.sin_addr) != 1)
2079 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2080 _("nat-server-read malformed address\n"), &mybuf, port);
2082 plugin->server_read_task =
2083 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2084 GNUNET_TIME_UNIT_FOREVER_REL,
2085 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2089 in_addr.sin_family = AF_INET;
2090 in_addr.sin_port = htons(port);
2092 * We have received an ICMP response, ostensibly from a non-NAT'd peer
2093 * that wants to connect to us! Send a message to establish a connection.
2095 sock = GNUNET_CONNECTION_create_from_sockaddr (plugin->env->sched, AF_INET, (struct sockaddr *)&in_addr,
2101 plugin->server_read_task =
2102 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2103 GNUNET_TIME_UNIT_FOREVER_REL,
2104 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2109 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2110 _("Sending TCP probe message!\n"), &mybuf, port);
2112 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 /*GNUNET_SERVER_connect_socket(plugin->server, sock);*/
2126 plugin->server_read_task =
2127 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2128 GNUNET_TIME_UNIT_FOREVER_REL,
2129 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2133 * Start the gnunet-nat-server process for users behind NAT.
2135 * @param plugin the transport plugin
2137 * @return GNUNET_YES if process was started, GNUNET_SYSERR on error
2140 tcp_transport_start_nat_server(struct Plugin *plugin)
2143 plugin->server_stdout = GNUNET_DISK_pipe(GNUNET_YES);
2144 if (plugin->server_stdout == NULL)
2145 return GNUNET_SYSERR;
2148 GNUNET_log (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 (GNUNET_ERROR_TYPE_DEBUG,
2157 "Failed to start gnunet-nat-server process\n");
2159 return GNUNET_SYSERR;
2161 /* Close the write end of the read pipe */
2162 GNUNET_DISK_pipe_close_end(plugin->server_stdout, GNUNET_DISK_PIPE_END_WRITE);
2164 plugin->server_stdout_handle = GNUNET_DISK_pipe_handle(plugin->server_stdout, GNUNET_DISK_PIPE_END_READ);
2165 plugin->server_read_task =
2166 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
2167 GNUNET_TIME_UNIT_FOREVER_REL,
2168 plugin->server_stdout_handle, &tcp_plugin_server_read, plugin);
2173 * Return the actual path to a file found in the current
2174 * PATH environment variable.
2176 * @param binary the name of the file to find
2179 get_path_from_PATH (char *binary)
2187 p = getenv ("PATH");
2190 path = GNUNET_strdup (p); /* because we write on it */
2191 buf = GNUNET_malloc (strlen (path) + 20);
2194 while (NULL != (end = strchr (pos, ':')))
2197 sprintf (buf, "%s/%s", pos, binary);
2198 if (GNUNET_DISK_file_test (buf) == GNUNET_YES)
2205 sprintf (buf, "%s/%s", pos, binary);
2206 if (GNUNET_DISK_file_test (buf) == GNUNET_YES)
2217 * Check whether the suid bit is set on a file.
2218 * Attempts to find the file using the current
2219 * PATH environment variable as a search path.
2221 * @param binary the name of the file to check
2224 check_gnunet_nat_binary(char *binary)
2226 struct stat statbuf;
2229 p = get_path_from_PATH (binary);
2232 if (0 != STAT (p, &statbuf))
2235 return GNUNET_SYSERR;
2238 if ( (0 != (statbuf.st_mode & S_ISUID)) &&
2239 (statbuf.st_uid == 0) )
2245 * Entry point for the plugin.
2247 * @param cls closure, the 'struct GNUNET_TRANSPORT_PluginEnvironment*'
2248 * @return the 'struct GNUNET_TRANSPORT_PluginFunctions*' or NULL on error
2251 libgnunet_plugin_transport_tcp_init (void *cls)
2253 static const struct GNUNET_SERVER_MessageHandler my_handlers[] = {
2254 {&handle_tcp_welcome, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_WELCOME,
2255 sizeof (struct WelcomeMessage)},
2256 {&handle_tcp_nat_probe, NULL, GNUNET_MESSAGE_TYPE_TRANSPORT_TCP_NAT_PROBE, sizeof (struct TCP_NAT_ProbeMessage)},
2257 {&handle_tcp_data, NULL, GNUNET_MESSAGE_TYPE_ALL, 0},
2260 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
2261 struct GNUNET_TRANSPORT_PluginFunctions *api;
2262 struct Plugin *plugin;
2263 struct GNUNET_SERVICE_Context *service;
2264 unsigned long long aport;
2265 unsigned long long bport;
2269 int only_nat_addresses;
2270 char *internal_address;
2271 char *external_address;
2272 struct sockaddr_in in_addr;
2273 struct IPv4TcpAddress t4;
2275 service = GNUNET_SERVICE_start ("transport-tcp", env->sched, env->cfg);
2276 if (service == NULL)
2278 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2279 _("Failed to start service for `%s' transport plugin.\n"),
2284 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
2288 /* We are behind nat (according to the user) */
2289 if (check_gnunet_nat_binary("gnunet-nat-server") == GNUNET_YES)
2291 behind_nat = GNUNET_YES;
2295 behind_nat = GNUNET_NO;
2296 GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Configuration specified you are behind a NAT, but gnunet-nat-server is not installed properly (suid bit not set)!\n");
2300 behind_nat = GNUNET_NO; /* We are not behind nat! */
2302 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
2306 if (check_gnunet_nat_binary("gnunet-nat-client") == GNUNET_YES)
2307 allow_nat = GNUNET_YES; /* We will try to connect to NAT'd peers */
2310 allow_nat = GNUNET_NO;
2311 GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Configuration specified you want to connect to NAT'd peers, but gnunet-nat-client is not installed properly (suid bit not set)!\n");
2315 allow_nat = GNUNET_NO; /* We don't want to try to help NAT'd peers */
2318 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
2320 "ONLY_NAT_ADDRESSES"))
2321 only_nat_addresses = GNUNET_YES; /* We will only report our addresses as NAT'd */
2323 only_nat_addresses = GNUNET_NO; /* We will report our addresses as NAT'd and non-NAT'd */
2325 external_address = NULL;
2326 if (((GNUNET_YES == behind_nat) || (GNUNET_YES == allow_nat)) && (GNUNET_OK !=
2327 GNUNET_CONFIGURATION_get_value_string (env->cfg,
2330 &external_address)))
2332 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2334 ("Require EXTERNAL_ADDRESS for service `%s' in configuration (either BEHIND_NAT or ALLOW_NAT set to YES)!\n"),
2336 GNUNET_SERVICE_stop (service);
2340 if ((external_address != NULL) && (inet_pton(AF_INET, external_address, &in_addr.sin_addr) != 1))
2342 GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Malformed EXTERNAL_ADDRESS %s given in configuration!\n", external_address);
2345 internal_address = NULL;
2346 if ((GNUNET_YES == behind_nat) && (GNUNET_OK !=
2347 GNUNET_CONFIGURATION_get_value_string (env->cfg,
2350 &internal_address)))
2352 GNUNET_log (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 (GNUNET_ERROR_TYPE_WARNING, "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 (GNUNET_ERROR_TYPE_ERROR,
2380 ("Require valid port number for service `%s' in configuration!\n"),
2382 GNUNET_free_non_null(external_address);
2383 GNUNET_free_non_null(internal_address);
2384 GNUNET_SERVICE_stop (service);
2390 plugin = GNUNET_malloc (sizeof (struct Plugin));
2391 plugin->open_port = bport;
2392 plugin->adv_port = aport;
2393 plugin->external_address = external_address;
2394 plugin->internal_address = internal_address;
2395 plugin->behind_nat = behind_nat;
2396 plugin->allow_nat = allow_nat;
2397 plugin->only_nat_addresses = only_nat_addresses;
2399 plugin->lsock = NULL;
2400 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
2402 api->send = &tcp_plugin_send;
2403 api->disconnect = &tcp_plugin_disconnect;
2404 api->address_pretty_printer = &tcp_plugin_address_pretty_printer;
2405 api->check_address = &tcp_plugin_check_address;
2406 api->address_to_string = &tcp_address_to_string;
2407 plugin->service = service;
2408 plugin->server = GNUNET_SERVICE_get_server (service);
2409 plugin->handlers = GNUNET_malloc (sizeof (my_handlers));
2410 memcpy (plugin->handlers, my_handlers, sizeof (my_handlers));
2413 sizeof (my_handlers) / sizeof (struct GNUNET_SERVER_MessageHandler);
2415 plugin->handlers[i].callback_cls = plugin;
2416 GNUNET_SERVER_add_handlers (plugin->server, plugin->handlers);
2418 if (plugin->behind_nat == GNUNET_YES)
2420 if (GNUNET_YES != tcp_transport_start_nat_server(plugin))
2422 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2425 ("Failed to start %s required for NAT in %s!\n"),
2428 GNUNET_free_non_null(external_address);
2429 GNUNET_free_non_null(internal_address);
2430 GNUNET_SERVICE_stop (service);
2436 if (allow_nat == GNUNET_YES)
2438 plugin->nat_wait_conns = GNUNET_CONTAINER_multihashmap_create(100);
2439 GNUNET_assert(plugin->nat_wait_conns != NULL);
2442 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("TCP transport listening on port %llu\n"), bport);
2444 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2445 _("TCP transport advertises itself as being on port %llu\n"),
2447 GNUNET_SERVER_disconnect_notify (plugin->server,
2450 GNUNET_CONFIGURATION_get_value_string(env->cfg, "transport-tcp", "BINDTO", &plugin->bind_address);
2452 if (plugin->behind_nat == GNUNET_NO)
2454 GNUNET_OS_network_interfaces_list (&process_interfaces, plugin);
2457 plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (env->sched,
2460 HOSTNAME_RESOLVE_TIMEOUT,
2461 &process_hostname_ips,
2464 if ((plugin->behind_nat == GNUNET_YES) && (inet_pton(AF_INET, plugin->external_address, &t4.ipv4_addr) == 1))
2466 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Notifying transport of address %s:0\n", plugin->external_address);
2467 t4.t_port = htons(0);
2468 add_to_address_list (plugin, &t4.ipv4_addr, sizeof (uint32_t));
2469 plugin->env->notify_address (plugin->env->cls,
2471 &t4, sizeof(t4), GNUNET_TIME_UNIT_FOREVER_REL);
2473 else if ((plugin->external_address != NULL) && (inet_pton(AF_INET, plugin->external_address, &t4.ipv4_addr) == 1))
2475 t4.t_port = htons(plugin->adv_port);
2476 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Notifying transport of address %s:%d\n", plugin->external_address, plugin->adv_port);
2477 add_to_address_list (plugin, &t4.ipv4_addr, sizeof (uint32_t));
2478 plugin->env->notify_address (plugin->env->cls,
2480 &t4, sizeof(t4), GNUNET_TIME_UNIT_FOREVER_REL);
2488 * Exit point from the plugin.
2491 libgnunet_plugin_transport_tcp_done (void *cls)
2493 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
2494 struct Plugin *plugin = api->cls;
2495 struct Session *session;
2496 struct LocalAddrList *lal;
2498 while (NULL != (session = plugin->sessions))
2499 disconnect_session (session);
2500 if (NULL != plugin->hostname_dns)
2502 GNUNET_RESOLVER_request_cancel (plugin->hostname_dns);
2503 plugin->hostname_dns = NULL;
2505 GNUNET_SERVICE_stop (plugin->service);
2506 GNUNET_free (plugin->handlers);
2507 while (NULL != (lal = plugin->lal_head))
2509 GNUNET_CONTAINER_DLL_remove (plugin->lal_head,
2515 if (plugin->behind_nat == GNUNET_YES)
2517 if (0 != PLIBC_KILL (plugin->server_pid, SIGTERM))
2518 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "kill");
2519 GNUNET_OS_process_wait (plugin->server_pid);
2521 GNUNET_free_non_null(plugin->bind_address);
2522 GNUNET_free (plugin);
2527 /* end of plugin_transport_tcp.c */