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3 (C) 2010 Christian Grothoff (and other contributing authors)
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22 * @file transport/plugin_transport_udp.c
23 * @brief Implementation of the UDP NAT punching
25 * @author Christian Grothoff
26 * @author Nathan Evans
28 * The idea with this transport is to connect gnunet peers to each other
29 * when ONE is behind a NAT. This is based on pwnat (http://samy.pl/pwnat)
30 * created by Samy Kamkar. When configured with the PWNAT options, this
31 * transport will start a server daemon which sends dummy ICMP and UDP
32 * messages out to a predefined address (typically 1.2.3.4).
34 * When a non-NAT'd peer (the client) learns of the NAT'd peer (the server)
35 * address, it will send ICMP RESPONSES to the NAT'd peers external address.
36 * The NAT box should forward these faked responses to the server, which
37 * can then connect directly to the non-NAT'd peer.
41 #include "gnunet_hello_lib.h"
42 #include "gnunet_connection_lib.h"
43 #include "gnunet_os_lib.h"
44 #include "gnunet_peerinfo_service.h"
45 #include "gnunet_protocols.h"
46 #include "gnunet_resolver_service.h"
47 #include "gnunet_server_lib.h"
48 #include "gnunet_service_lib.h"
49 #include "gnunet_signatures.h"
50 #include "gnunet_statistics_service.h"
51 #include "gnunet_transport_service.h"
52 #include "plugin_transport.h"
53 #include "transport.h"
55 #define DEBUG_UDP GNUNET_YES
60 * Transport cost to peer, always 1 for UDP (direct connection)
62 #define UDP_DIRECT_DISTANCE 1
64 #define DEFAULT_NAT_PORT 0
67 * How long until we give up on transmitting the welcome message?
69 #define HOSTNAME_RESOLVE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
72 * Starting port for listening and sending, eventually a config value
74 #define UDP_NAT_DEFAULT_PORT 22086
77 * UDP Message-Packet header.
84 struct GNUNET_MessageHeader header;
87 * What is the identity of the sender (GNUNET_hash of public key)
89 struct GNUNET_PeerIdentity sender;
94 * Network format for IPv4 addresses.
99 * IPv4 address, in network byte order.
104 * Port number, in network byte order.
111 * Network format for IPv6 addresses.
113 struct IPv6UdpAddress
118 unsigned char ipv6_addr[16];
121 * Port number, in network byte order.
126 /* Forward definition */
129 struct PrettyPrinterContext
131 GNUNET_TRANSPORT_AddressStringCallback asc;
141 struct MessageQueue *next;
144 * Session this message belongs to
146 struct PeerSession *session;
149 * Actual message to be sent
154 * Size of message buffer to be sent
159 * When to discard this message
161 struct GNUNET_TIME_Absolute timeout;
164 * Continuation to call when this message goes out
166 GNUNET_TRANSPORT_TransmitContinuation cont;
169 * closure for continuation
176 * UDP NAT Probe message definition
178 struct UDP_NAT_ProbeMessage
183 struct GNUNET_MessageHeader header;
188 * UDP NAT Probe message reply definition
190 struct UDP_NAT_ProbeMessageReply
195 struct GNUNET_MessageHeader header;
201 * UDP NAT Probe message confirm definition
203 struct UDP_NAT_ProbeMessageConfirmation
208 struct GNUNET_MessageHeader header;
221 * Stored in a linked list.
223 struct PeerSession *next;
226 * Pointer to the global plugin struct.
228 struct Plugin *plugin;
231 * To whom are we talking to (set to our identity
232 * if we are still waiting for the welcome message)
234 struct GNUNET_PeerIdentity target;
237 * Address of the other peer (either based on our 'connect'
238 * call or on our 'accept' call).
243 * Length of connect_addr.
248 * Are we still expecting the welcome message? (GNUNET_YES/GNUNET_NO)
250 int expecting_welcome;
253 * From which socket do we need to send to this peer?
255 struct GNUNET_NETWORK_Handle *sock;
258 * Queue of messages for this peer, in the case that
259 * we have to await a connection...
261 struct MessageQueue *messages;
265 struct UDP_NAT_Probes
271 struct UDP_NAT_Probes *next;
274 * Address string that the server process returned to us
276 char *address_string;
279 * Timeout for this set of probes
281 struct GNUNET_TIME_Absolute timeout;
284 * Count of how many probes we've attempted
289 * The plugin this probe belongs to
291 struct Plugin *plugin;
294 * The task used to send these probes
296 GNUNET_SCHEDULER_TaskIdentifier task;
299 * Network address (always ipv4!)
301 struct IPv4UdpAddress addr;
307 * Encapsulation of all of the state of the plugin.
314 struct GNUNET_TRANSPORT_PluginEnvironment *env;
317 * Handle to the network service.
319 struct GNUNET_SERVICE_Context *service;
322 * Session of peers with whom we are currently connected
324 struct PeerSession *sessions;
327 * Handle for request of hostname resolution, non-NULL if pending.
329 struct GNUNET_RESOLVER_RequestHandle *hostname_dns;
332 * ID of task used to update our addresses when one expires.
334 GNUNET_SCHEDULER_TaskIdentifier address_update_task;
339 GNUNET_SCHEDULER_TaskIdentifier select_task;
347 * The external address given to us by the user. Must be actual
348 * outside visible address for NAT punching to work.
350 char *external_address;
353 * The internal address given to us by the user (or discovered).
355 char *internal_address;
360 struct GNUNET_NETWORK_FDSet *rs;
363 * stdout pipe handle for the gnunet-nat-server process
365 struct GNUNET_DISK_PipeHandle *server_stdout;
368 * stdout file handle (for reading) for the gnunet-nat-server process
370 const struct GNUNET_DISK_FileHandle *server_stdout_handle;
373 * ID of select gnunet-nat-server stdout read task
375 GNUNET_SCHEDULER_TaskIdentifier server_read_task;
378 * Is this transport configured to be behind a NAT?
383 * Is this transport configured to allow connections to NAT'd peers?
388 * Should this transport advertise only NAT addresses (port set to 0)?
389 * If not, all addresses will be duplicated for NAT punching and regular
392 int only_nat_addresses;
395 * The process id of the server process (if behind NAT)
402 struct UDP_NAT_Probes *probes;
409 /* The network handle */
410 struct GNUNET_NETWORK_Handle *desc;
412 /* The port we bound to */
416 /* *********** globals ************* */
419 * the socket that we transmit all data with
421 static struct UDP_Sock_Info udp_sock;
425 * Forward declaration.
428 udp_probe_continuation (void *cls, const struct GNUNET_PeerIdentity *target, int result);
432 * Disconnect from a remote node. Clean up session if we have one for this peer
434 * @param cls closure for this call (should be handle to Plugin)
435 * @param target the peeridentity of the peer to disconnect
436 * @return GNUNET_OK on success, GNUNET_SYSERR if the operation failed
439 udp_disconnect (void *cls, const struct GNUNET_PeerIdentity *target)
441 /** TODO: Implement! */
446 * Shutdown the server process (stop receiving inbound traffic). Maybe
449 * @param cls Handle to the plugin for this transport
451 * @return returns the number of sockets successfully closed,
452 * should equal the number of sockets successfully opened
455 udp_transport_server_stop (void *cls)
457 struct Plugin *plugin = cls;
462 if (plugin->select_task != GNUNET_SCHEDULER_NO_TASK)
464 GNUNET_SCHEDULER_cancel (plugin->env->sched, plugin->select_task);
465 plugin->select_task = GNUNET_SCHEDULER_NO_TASK;
468 ok = GNUNET_NETWORK_socket_close (udp_sock.desc);
470 udp_sock.desc = NULL;
473 if (plugin->behind_nat == GNUNET_YES)
475 if (0 != PLIBC_KILL (plugin->server_pid, SIGTERM))
477 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "kill");
479 GNUNET_OS_process_wait (plugin->server_pid);
482 if (ret != GNUNET_OK)
483 return GNUNET_SYSERR;
489 find_session (struct Plugin *plugin, const struct GNUNET_PeerIdentity *peer)
491 struct PeerSession *pos;
493 pos = plugin->sessions;
496 if (memcmp(&pos->target, peer, sizeof(struct GNUNET_PeerIdentity)) == 0)
506 * Actually send out the message, assume we've got the address and
507 * send_handle squared away!
510 * @param send_handle which handle to send message on
511 * @param target who should receive this message (ignored by UDP)
512 * @param msgbuf one or more GNUNET_MessageHeader(s) strung together
513 * @param msgbuf_size the size of the msgbuf to send
514 * @param priority how important is the message (ignored by UDP)
515 * @param timeout when should we time out (give up) if we can not transmit?
516 * @param addr the addr to send the message to, needs to be a sockaddr for us
517 * @param addrlen the len of addr
518 * @param cont continuation to call once the message has
519 * been transmitted (or if the transport is ready
520 * for the next transmission call; or if the
521 * peer disconnected...)
522 * @param cont_cls closure for cont
523 * @return the number of bytes written
526 udp_real_send (void *cls,
527 struct GNUNET_NETWORK_Handle *send_handle,
528 const struct GNUNET_PeerIdentity *target,
531 unsigned int priority,
532 struct GNUNET_TIME_Relative timeout,
535 GNUNET_TRANSPORT_TransmitContinuation cont,
538 struct Plugin *plugin = cls;
539 struct UDPMessage *message;
542 struct sockaddr_in a4;
543 struct sockaddr_in6 a6;
544 const struct IPv4UdpAddress *t4;
545 const struct IPv6UdpAddress *t6;
549 if ((addr == NULL) || (addrlen == 0))
552 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
553 ("udp_real_send called without address, returning!\n"));
556 cont (cont_cls, target, GNUNET_SYSERR);
557 return 0; /* Can never send if we don't have an address!! */
560 /* Build the message to be sent */
561 message = GNUNET_malloc (sizeof (struct UDPMessage) + msgbuf_size);
562 ssize = sizeof (struct UDPMessage) + msgbuf_size;
564 message->header.size = htons (ssize);
565 message->header.type = htons (0);
566 memcpy (&message->sender, plugin->env->my_identity,
567 sizeof (struct GNUNET_PeerIdentity));
568 memcpy (&message[1], msgbuf, msgbuf_size);
570 if (addrlen == sizeof (struct IPv6UdpAddress))
573 memset (&a6, 0, sizeof (a6));
574 #if HAVE_SOCKADDR_IN_SIN_LEN
575 a6.sin6_len = sizeof (a6);
577 a6.sin6_family = AF_INET6;
578 a6.sin6_port = t6->u6_port;
579 memcpy (&a6.sin6_addr,
581 sizeof (struct in6_addr));
585 else if (addrlen == sizeof (struct IPv4UdpAddress))
588 memset (&a4, 0, sizeof (a4));
589 #if HAVE_SOCKADDR_IN_SIN_LEN
590 a4.sin_len = sizeof (a4);
592 a4.sin_family = AF_INET;
593 a4.sin_port = t4->u_port;
594 a4.sin_addr.s_addr = t4->ipv4_addr;
601 GNUNET_free (message);
605 /* Actually send the message */
607 GNUNET_NETWORK_socket_sendto (send_handle, message, ssize,
613 if (sent == GNUNET_SYSERR)
614 cont (cont_cls, target, GNUNET_SYSERR);
617 cont (cont_cls, target, GNUNET_OK);
621 GNUNET_free (message);
626 * We learned about a peer (possibly behind NAT) so run the
627 * gnunet-nat-client to send dummy ICMP responses
629 * @param plugin the plugin for this transport
630 * @param addr the address of the peer
631 * @param addrlen the length of the address
634 run_gnunet_nat_client (struct Plugin *plugin, const char *addr, size_t addrlen)
636 char addr_buf[INET_ADDRSTRLEN];
637 char *address_as_string;
638 char *port_as_string;
640 const struct IPv4UdpAddress *t4;
642 GNUNET_assert(addrlen == sizeof(struct IPv4UdpAddress));
643 t4 = (struct IPv4UdpAddress *)addr;
645 if (NULL == inet_ntop (AF_INET,
647 addr_buf, INET_ADDRSTRLEN))
649 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
652 address_as_string = GNUNET_strdup (addr_buf);
653 GNUNET_asprintf(&port_as_string, "%d", plugin->port);
655 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
656 _("Running gnunet-nat-client with arguments: %s %s %d\n"), plugin->external_address, address_as_string, plugin->port);
659 /* Start the server process */
660 pid = GNUNET_OS_start_process(NULL, NULL, "gnunet-nat-client", "gnunet-nat-client", plugin->external_address, address_as_string, port_as_string, NULL);
661 GNUNET_free(address_as_string);
662 GNUNET_free(port_as_string);
663 GNUNET_OS_process_wait (pid);
667 * Function that can be used by the transport service to transmit
668 * a message using the plugin.
671 * @param target who should receive this message (ignored by UDP)
672 * @param msgbuf one or more GNUNET_MessageHeader(s) strung together
673 * @param msgbuf_size the size of the msgbuf to send
674 * @param priority how important is the message (ignored by UDP)
675 * @param timeout when should we time out (give up) if we can not transmit?
676 * @param session identifier used for this session (can be NULL)
677 * @param addr the addr to send the message to, needs to be a sockaddr for us
678 * @param addrlen the len of addr
679 * @param force_address not used, we had better have an address to send to
680 * because we are stateless!!
681 * @param cont continuation to call once the message has
682 * been transmitted (or if the transport is ready
683 * for the next transmission call; or if the
684 * peer disconnected...)
685 * @param cont_cls closure for cont
687 * @return the number of bytes written (may return 0 and the message can
688 * still be transmitted later!)
691 udp_plugin_send (void *cls,
692 const struct GNUNET_PeerIdentity *target,
695 unsigned int priority,
696 struct GNUNET_TIME_Relative timeout,
697 struct Session *session,
701 GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
703 struct Plugin *plugin = cls;
705 struct MessageQueue *temp_message;
706 struct PeerSession *peer_session;
708 const struct IPv4UdpAddress *t4;
710 GNUNET_assert (NULL == session);
712 other_peer_natd = GNUNET_NO;
713 if (addrlen == sizeof(struct IPv4UdpAddress))
716 if (ntohs(t4->u_port) == 0)
717 other_peer_natd = GNUNET_YES;
719 else if (addrlen != sizeof(struct IPv6UdpAddress))
722 return -1; /* Must have an address to send to */
727 if ((other_peer_natd == GNUNET_YES) && (plugin->allow_nat == GNUNET_YES))
729 peer_session = find_session(plugin, target);
730 if (peer_session == NULL) /* We have a new peer to add */
733 * The first time, we can assume we have no knowledge of a
734 * working port for this peer, call the ICMP/UDP message sender
737 peer_session = GNUNET_malloc(sizeof(struct PeerSession));
738 peer_session->connect_addr = GNUNET_malloc(addrlen);
739 memcpy(peer_session->connect_addr, addr, addrlen);
740 peer_session->connect_alen = addrlen;
741 peer_session->plugin = plugin;
742 peer_session->sock = NULL;
743 memcpy(&peer_session->target, target, sizeof(struct GNUNET_PeerIdentity));
744 peer_session->expecting_welcome = GNUNET_YES;
746 peer_session->next = plugin->sessions;
747 plugin->sessions = peer_session;
749 peer_session->messages = GNUNET_malloc(sizeof(struct MessageQueue));
750 peer_session->messages->msgbuf = GNUNET_malloc(msgbuf_size);
751 memcpy(peer_session->messages->msgbuf, msgbuf, msgbuf_size);
752 peer_session->messages->msgbuf_size = msgbuf_size;
753 peer_session->messages->timeout = GNUNET_TIME_relative_to_absolute(timeout);
754 peer_session->messages->cont = cont;
755 peer_session->messages->cont_cls = cont_cls;
757 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
758 _("Other peer is NAT'd, set up peer session for peer %s\n"), GNUNET_i2s(target));
760 run_gnunet_nat_client(plugin, addr, addrlen);
764 if (peer_session->expecting_welcome == GNUNET_NO) /* We are "connected" */
766 sent = udp_real_send(cls, peer_session->sock, target, msgbuf, msgbuf_size, priority, timeout, peer_session->connect_addr, peer_session->connect_alen, cont, cont_cls);
768 else /* Haven't gotten a response from this peer, queue message */
770 temp_message = GNUNET_malloc(sizeof(struct MessageQueue));
771 temp_message->msgbuf = GNUNET_malloc(msgbuf_size);
772 memcpy(temp_message->msgbuf, msgbuf, msgbuf_size);
773 temp_message->msgbuf_size = msgbuf_size;
774 temp_message->timeout = GNUNET_TIME_relative_to_absolute(timeout);
775 temp_message->cont = cont;
776 temp_message->cont_cls = cont_cls;
777 temp_message->next = peer_session->messages;
778 peer_session->messages = temp_message;
782 else if (other_peer_natd == GNUNET_NO) /* Other peer not behind a NAT, so we can just send the message as is */
784 sent = udp_real_send(cls, udp_sock.desc, target, msgbuf, msgbuf_size, priority, timeout, addr, addrlen, cont, cont_cls);
786 else /* Other peer is NAT'd, but we don't want to play with them (or can't!) */
787 return GNUNET_SYSERR;
789 /* When GNUNET_SYSERR is returned from udp_real_send, we will still call
790 * the callback so must not return GNUNET_SYSERR!
791 * If we do, then transport context get freed twice. */
792 if (sent == GNUNET_SYSERR)
800 * Add the IP of our network interface to the list of
801 * our external IP addresses.
804 process_interfaces (void *cls,
807 const struct sockaddr *addr, socklen_t addrlen)
809 struct Plugin *plugin = cls;
811 struct IPv4UdpAddress t4;
812 struct IPv6UdpAddress t6;
818 af = addr->sa_family;
821 t4.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
822 if ((plugin->behind_nat == GNUNET_YES) && (plugin->only_nat_addresses == GNUNET_YES))
824 t4.u_port = htons (DEFAULT_NAT_PORT);
826 else if (plugin->behind_nat == GNUNET_YES) /* We are behind NAT, but will advertise NAT and normal addresses */
828 addr_nat = GNUNET_malloc(sizeof(t4));
829 memcpy(addr_nat, &t4, sizeof(t4));
830 t4.u_port = plugin->port;
831 ((struct IPv4UdpAddress *)addr_nat)->u_port = htons(DEFAULT_NAT_PORT);
835 t4.u_port = htons(plugin->port);
840 else if (af == AF_INET6)
843 if (IN6_IS_ADDR_LINKLOCAL (&((struct sockaddr_in6 *) addr)->sin6_addr))
845 /* skip link local addresses */
848 memcpy (&t6.ipv6_addr,
849 &((struct sockaddr_in6 *) addr)->sin6_addr,
850 sizeof (struct in6_addr));
851 if ((plugin->behind_nat == GNUNET_YES) && (plugin->only_nat_addresses == GNUNET_YES))
853 t6.u6_port = htons (0);
855 else if (plugin->behind_nat == GNUNET_YES)
857 addr_nat = GNUNET_malloc(sizeof(t6));
858 memcpy(addr_nat, &t6, sizeof(t6));
859 t6.u6_port = plugin->port;
860 ((struct IPv6UdpAddress *)addr_nat)->u6_port = htons(DEFAULT_NAT_PORT);
864 t6.u6_port = htons (plugin->port);
876 GNUNET_log (GNUNET_ERROR_TYPE_INFO |
877 GNUNET_ERROR_TYPE_BULK,
878 _("Found address `%s' (%s)\n"),
879 GNUNET_a2s (addr, addrlen), name);
881 if (addr_nat != NULL)
883 plugin->env->notify_address (plugin->env->cls,
885 addr_nat, args, GNUNET_TIME_UNIT_FOREVER_REL);
886 GNUNET_log (GNUNET_ERROR_TYPE_INFO |
887 GNUNET_ERROR_TYPE_BULK,
888 _("Found NAT address `%s' (%s)\n"),
889 GNUNET_a2s (addr_nat, args), name);
890 GNUNET_free(addr_nat);
893 plugin->env->notify_address (plugin->env->cls,
895 arg, args, GNUNET_TIME_UNIT_FOREVER_REL);
902 * Function called by the resolver for each address obtained from DNS
903 * for our own hostname. Add the addresses to the list of our
904 * external IP addresses.
907 * @param addr one of the addresses of the host, NULL for the last address
908 * @param addrlen length of the address
911 process_hostname_ips (void *cls,
912 const struct sockaddr *addr, socklen_t addrlen)
914 struct Plugin *plugin = cls;
918 plugin->hostname_dns = NULL;
921 process_interfaces (plugin, "<hostname>", GNUNET_YES, addr, addrlen);
926 * Send UDP probe messages or UDP keepalive messages, depending on the
927 * state of the connection.
929 * @param cls closure for this call (should be the main Plugin)
930 * @param tc task context for running this
933 send_udp_probe_message (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
935 struct UDP_NAT_Probes *probe = cls;
936 struct UDP_NAT_ProbeMessage *message;
937 struct Plugin *plugin = probe->plugin;
939 message = GNUNET_malloc(sizeof(struct UDP_NAT_ProbeMessage));
940 message->header.size = htons(sizeof(struct UDP_NAT_ProbeMessage));
941 message->header.type = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE);
942 /* If they gave us a port, use that. If not, try our port. */
943 if (ntohs(probe->addr.u_port) == 0)
944 probe->addr.u_port = htons(plugin->port);
947 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
948 _("Sending a probe to port %d\n"), ntohs(probe->addr.u_port));
953 udp_real_send(plugin, udp_sock.desc, NULL,
954 (char *)message, ntohs(message->header.size), 0,
955 GNUNET_TIME_relative_get_unit(),
956 &probe->addr, sizeof(probe->addr),
957 &udp_probe_continuation, probe);
959 GNUNET_free(message);
964 * Continuation for probe sends. If the last probe was sent
965 * "successfully", schedule sending of another one. If not,
969 udp_probe_continuation (void *cls, const struct GNUNET_PeerIdentity *target, int result)
971 struct UDP_NAT_Probes *probe = cls;
972 struct Plugin *plugin = probe->plugin;
974 if ((result == GNUNET_OK) && (probe->count < MAX_PROBES))
977 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
978 _("Scheduling next probe for 10000 milliseconds\n"));
980 probe->task = GNUNET_SCHEDULER_add_delayed(plugin->env->sched, GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MILLISECONDS, 10000), &send_udp_probe_message, probe);
982 else /* Destroy the probe context. */
985 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
986 _("Sending probe didn't go well...\n"));
992 * Find probe message by address
994 * @param plugin the plugin for this transport
995 * @param address_string the ip address as a string
997 struct UDP_NAT_Probes *
998 find_probe(struct Plugin *plugin, char * address_string)
1000 struct UDP_NAT_Probes *pos;
1002 pos = plugin->probes;
1004 if (strcmp(pos->address_string, address_string) == 0)
1012 * @param cls the plugin handle
1013 * @param tc the scheduling context (for rescheduling this function again)
1015 * We have been notified that gnunet-nat-server has written something to stdout.
1016 * Handle the output, then reschedule this function to be called again once
1017 * more is available.
1021 udp_plugin_server_read (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1023 struct Plugin *plugin = cls;
1026 memset(&mybuf, 0, sizeof(mybuf));
1028 struct UDP_NAT_Probes *temp_probe;
1031 struct IPv4UdpAddress a4;
1033 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
1036 bytes = GNUNET_DISK_file_read(plugin->server_stdout_handle, &mybuf, sizeof(mybuf));
1041 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1042 _("Finished reading from server stdout with code: %d\n"), bytes);
1049 for (i = 0; i < sizeof(mybuf); i++)
1051 if (mybuf[i] == '\n')
1054 if ((mybuf[i] == ':') && (i + 1 < sizeof(mybuf)))
1057 port_start = &mybuf[i + 1];
1061 if (port_start != NULL)
1062 port = atoi(port_start);
1065 plugin->server_read_task =
1066 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
1067 GNUNET_TIME_UNIT_FOREVER_REL,
1068 plugin->server_stdout_handle, &udp_plugin_server_read, plugin);
1073 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1074 _("nat-server-read read: %s port %d\n"), &mybuf, port);
1078 * We have received an ICMP response, ostensibly from a non-NAT'd peer
1079 * that wants to connect to us! Send a message to establish a connection.
1081 if (inet_pton(AF_INET, &mybuf[0], &a4.ipv4_addr) != 1)
1084 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "udp",
1085 _("nat-server-read malformed address\n"), &mybuf, port);
1087 plugin->server_read_task =
1088 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
1089 GNUNET_TIME_UNIT_FOREVER_REL,
1090 plugin->server_stdout_handle, &udp_plugin_server_read, plugin);
1094 temp_probe = find_probe(plugin, &mybuf[0]);
1096 if (temp_probe == NULL)
1098 temp_probe = GNUNET_malloc(sizeof(struct UDP_NAT_Probes));
1099 temp_probe->address_string = strdup(&mybuf[0]);
1100 GNUNET_assert (1 == inet_pton(AF_INET, &mybuf[0], &temp_probe->addr.ipv4_addr));
1101 temp_probe->addr.u_port = htons(port);
1102 temp_probe->next = plugin->probes;
1103 temp_probe->plugin = plugin;
1104 temp_probe->task = GNUNET_SCHEDULER_add_delayed(plugin->env->sched, GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MILLISECONDS, 500), &send_udp_probe_message, temp_probe);
1105 plugin->probes = temp_probe;
1108 plugin->server_read_task =
1109 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
1110 GNUNET_TIME_UNIT_FOREVER_REL,
1111 plugin->server_stdout_handle, &udp_plugin_server_read, plugin);
1117 * Demultiplexer for UDP NAT messages
1119 * @param plugin the main plugin for this transport
1120 * @param sender from which peer the message was received
1121 * @param currhdr pointer to the header of the message
1122 * @param sender_addr the address from which the message was received
1123 * @param fromlen the length of the address
1124 * @param sockinfo which socket did we receive the message on
1127 udp_demultiplexer(struct Plugin *plugin, struct GNUNET_PeerIdentity *sender,
1128 const struct GNUNET_MessageHeader *currhdr,
1129 const void *sender_addr,
1130 size_t fromlen, struct UDP_Sock_Info *sockinfo)
1132 struct UDP_NAT_ProbeMessageReply *outgoing_probe_reply;
1133 struct UDP_NAT_ProbeMessageConfirmation *outgoing_probe_confirmation;
1135 char addr_buf[INET_ADDRSTRLEN];
1136 struct UDP_NAT_Probes *outgoing_probe;
1137 struct PeerSession *peer_session;
1138 struct MessageQueue *pending_message;
1139 struct MessageQueue *pending_message_temp;
1140 uint16_t incoming_port;
1142 if (memcmp(sender, plugin->env->my_identity, sizeof(struct GNUNET_PeerIdentity)) == 0)
1145 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1146 _("Received a message from myself, dropping!!!\n"));
1152 GNUNET_assert(sender_addr != NULL); /* Can recvfrom have a NULL address? */
1153 if (fromlen == sizeof(struct IPv4UdpAddress))
1155 incoming_port = ntohs(((struct IPv4UdpAddress *)sender_addr)->u_port);
1157 else if (fromlen == sizeof(struct IPv6UdpAddress))
1159 incoming_port = ntohs(((struct IPv6UdpAddress *)sender_addr)->u6_port);
1162 switch (ntohs(currhdr->type))
1164 case GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE:
1165 /* Send probe reply */
1166 outgoing_probe_reply = GNUNET_malloc(sizeof(struct UDP_NAT_ProbeMessageReply));
1167 outgoing_probe_reply->header.size = htons(sizeof(struct UDP_NAT_ProbeMessageReply));
1168 outgoing_probe_reply->header.type = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE_REPLY);
1171 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1172 _("Received a probe on listen port %d, sent_from port %d\n"), sockinfo->port, incoming_port);
1175 udp_real_send(plugin, sockinfo->desc, NULL,
1176 (char *)outgoing_probe_reply,
1177 ntohs(outgoing_probe_reply->header.size), 0,
1178 GNUNET_TIME_relative_get_unit(),
1179 sender_addr, fromlen,
1183 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1184 _("Sent PROBE REPLY to port %d on outgoing port %d\n"), incoming_port, sockinfo->port);
1186 GNUNET_free(outgoing_probe_reply);
1188 case GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE_REPLY:
1189 /* Check for existing probe, check ports returned, send confirmation if all is well */
1191 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1192 _("Received PROBE REPLY from port %d on incoming port %d\n"), incoming_port, sockinfo->port);
1194 if (sizeof(sender_addr) == sizeof(struct IPv4UdpAddress))
1196 memset(&addr_buf, 0, sizeof(addr_buf));
1197 if (NULL == inet_ntop (AF_INET,
1198 &((struct IPv4UdpAddress *) sender_addr)->ipv4_addr, addr_buf,
1201 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
1204 outgoing_probe = find_probe(plugin, &addr_buf[0]);
1205 if (outgoing_probe != NULL)
1208 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1209 _("Sending confirmation that we were reached!\n"));
1211 outgoing_probe_confirmation = GNUNET_malloc(sizeof(struct UDP_NAT_ProbeMessageConfirmation));
1212 outgoing_probe_confirmation->header.size = htons(sizeof(struct UDP_NAT_ProbeMessageConfirmation));
1213 outgoing_probe_confirmation->header.type = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE_CONFIRM);
1215 udp_real_send(plugin, sockinfo->desc, NULL, (char *)outgoing_probe_confirmation, ntohs(outgoing_probe_confirmation->header.size), 0, GNUNET_TIME_relative_get_unit(), sender_addr, fromlen, NULL, NULL);
1217 if (outgoing_probe->task != GNUNET_SCHEDULER_NO_TASK)
1219 GNUNET_SCHEDULER_cancel(plugin->env->sched, outgoing_probe->task);
1220 outgoing_probe->task = GNUNET_SCHEDULER_NO_TASK;
1221 /* Schedule task to timeout and remove probe if confirmation not received */
1223 GNUNET_free(outgoing_probe_confirmation);
1228 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1229 _("Received a probe reply, but have no record of a sent probe!\n"));
1234 case GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE_CONFIRM:
1235 peer_session = find_session(plugin, sender);
1237 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1238 _("Looking up peer session for peer %s\n"), GNUNET_i2s(sender));
1240 if (peer_session == NULL) /* Shouldn't this NOT happen? */
1243 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1244 _("Peer not in list, adding (THIS MAY BE A MISTAKE) %s\n"), GNUNET_i2s(sender));
1246 peer_session = GNUNET_malloc(sizeof(struct PeerSession));
1247 peer_session->connect_addr = GNUNET_malloc(fromlen);
1248 memcpy(peer_session->connect_addr, sender_addr, fromlen);
1249 peer_session->connect_alen = fromlen;
1250 peer_session->plugin = plugin;
1251 peer_session->sock = sockinfo->desc;
1252 memcpy(&peer_session->target, sender, sizeof(struct GNUNET_PeerIdentity));
1253 peer_session->expecting_welcome = GNUNET_NO;
1255 peer_session->next = plugin->sessions;
1256 plugin->sessions = peer_session;
1258 peer_session->messages = NULL;
1260 else if (peer_session->expecting_welcome == GNUNET_YES)
1262 peer_session->expecting_welcome = GNUNET_NO;
1263 peer_session->sock = sockinfo->desc;
1264 if (peer_session->connect_alen == sizeof(struct IPv4UdpAddress))
1266 ((struct IPv4UdpAddress *)peer_session->connect_addr)->u_port = htons(incoming_port);
1268 else if (peer_session->connect_alen == sizeof(struct IPv4UdpAddress))
1270 ((struct IPv6UdpAddress *)peer_session->connect_addr)->u6_port = htons(incoming_port);
1274 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1275 _("Received a probe confirmation, will send to peer on port %d\n"), incoming_port);
1277 if (peer_session->messages != NULL)
1280 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1281 _("Received a probe confirmation, sending queued messages.\n"));
1283 pending_message = peer_session->messages;
1285 while (pending_message != NULL)
1288 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1289 _("sending queued message %d\n"), count);
1291 udp_real_send(plugin,
1293 &peer_session->target,
1294 pending_message->msgbuf,
1295 pending_message->msgbuf_size, 0,
1296 GNUNET_TIME_relative_get_unit(),
1297 peer_session->connect_addr,
1298 peer_session->connect_alen,
1299 pending_message->cont,
1300 pending_message->cont_cls);
1302 pending_message_temp = pending_message;
1303 pending_message = pending_message->next;
1304 GNUNET_free(pending_message_temp->msgbuf);
1305 GNUNET_free(pending_message_temp);
1307 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1308 _("finished sending queued message %d\n"), count);
1318 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1319 _("Received probe confirmation for already confirmed peer!\n"));
1322 /* Received confirmation, add peer with address/port specified */
1324 case GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE_KEEPALIVE:
1325 /* Once we've sent NAT_PROBE_CONFIRM change to sending keepalives */
1326 /* If we receive these just ignore! */
1330 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1331 _("Sending message type %d to transport\n!"), ntohs(currhdr->type));
1333 plugin->env->receive (plugin->env->cls, sender, currhdr, UDP_DIRECT_DISTANCE,
1334 NULL, sender_addr, fromlen);
1341 * @param cls the plugin handle
1342 * @param tc the scheduling context (for rescheduling this function again)
1344 * We have been notified that our writeset has something to read. We don't
1345 * know which socket needs to be read, so we have to check each one
1346 * Then reschedule this function to be called again once more is available.
1350 udp_plugin_select (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1352 struct Plugin *plugin = cls;
1354 struct UDPMessage *msg;
1355 struct GNUNET_PeerIdentity *sender;
1356 unsigned int buflen;
1364 const struct GNUNET_MessageHeader *currhdr;
1365 struct IPv4UdpAddress t4;
1366 struct IPv6UdpAddress t6;
1367 const struct sockaddr_in *s4;
1368 const struct sockaddr_in6 *s6;
1373 plugin->select_task = GNUNET_SCHEDULER_NO_TASK;
1375 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
1381 buflen = GNUNET_NETWORK_socket_recvfrom_amount (udp_sock.desc);
1383 if (buflen == GNUNET_NO)
1386 buf = GNUNET_malloc (buflen);
1387 fromlen = sizeof (addr);
1388 memset (&addr, 0, sizeof(addr));
1390 GNUNET_NETWORK_socket_recvfrom (udp_sock.desc, buf, buflen,
1391 (struct sockaddr *)&addr, &fromlen);
1393 if (AF_INET == ((struct sockaddr *)addr)->sa_family)
1395 s4 = (const struct sockaddr_in*) &addr;
1396 t4.u_port = s4->sin_port;
1397 t4.ipv4_addr = s4->sin_addr.s_addr;
1399 calen = sizeof (t4);
1401 else if (AF_INET6 == ((struct sockaddr *)addr)->sa_family)
1403 s6 = (const struct sockaddr_in6*) &addr;
1404 t6.u6_port = s6->sin6_port;
1405 memcpy (&t6.ipv6_addr,
1407 sizeof (struct in6_addr));
1409 calen = sizeof (t6);
1423 msg = (struct UDPMessage *) buf;
1425 if (ntohs (msg->header.size) < sizeof (struct UDPMessage))
1431 msgbuf = (char *)&msg[1];
1432 sender = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
1433 memcpy (sender, &msg->sender, sizeof (struct GNUNET_PeerIdentity));
1437 tsize = ntohs (msg->header.size) - sizeof(struct UDPMessage);
1439 while (offset < tsize)
1441 currhdr = (struct GNUNET_MessageHeader *)&msgbuf[offset];
1442 udp_demultiplexer(plugin, sender, currhdr, ca, calen, &udp_sock);
1443 offset += ntohs(currhdr->size);
1446 GNUNET_free_non_null (buf);
1447 GNUNET_free_non_null (sender);
1450 plugin->select_task =
1451 GNUNET_SCHEDULER_add_select (plugin->env->sched,
1452 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1453 GNUNET_SCHEDULER_NO_TASK,
1454 GNUNET_TIME_UNIT_FOREVER_REL, plugin->rs,
1455 NULL, &udp_plugin_select, plugin);
1460 * Create a slew of UDP sockets. If possible, use IPv6, otherwise
1463 * @param cls closure for server start, should be a struct Plugin *
1465 * @return number of sockets created or GNUNET_SYSERR on error
1468 udp_transport_server_start (void *cls)
1470 struct Plugin *plugin = cls;
1471 struct sockaddr_in serverAddrv4;
1472 struct sockaddr_in6 serverAddrv6;
1473 struct sockaddr *serverAddr;
1475 int sockets_created;
1477 sockets_created = 0;
1479 if (plugin->behind_nat == GNUNET_YES)
1481 /* Pipe to read from started processes stdout (on read end) */
1482 plugin->server_stdout = GNUNET_DISK_pipe(GNUNET_YES);
1483 if (plugin->server_stdout == NULL)
1484 return sockets_created;
1486 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1488 "Starting gnunet-nat-server process cmd: %s %s\n", "gnunet-nat-server", plugin->internal_address);
1490 /* Start the server process */
1491 plugin->server_pid = GNUNET_OS_start_process(NULL, plugin->server_stdout, "gnunet-nat-server", "gnunet-nat-server", plugin->internal_address, NULL);
1492 if (plugin->server_pid == GNUNET_SYSERR)
1495 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1497 "Failed to start gnunet-nat-server process\n");
1499 return GNUNET_SYSERR;
1501 /* Close the write end of the read pipe */
1502 GNUNET_DISK_pipe_close_end(plugin->server_stdout, GNUNET_DISK_PIPE_END_WRITE);
1504 plugin->server_stdout_handle = GNUNET_DISK_pipe_handle(plugin->server_stdout, GNUNET_DISK_PIPE_END_READ);
1505 plugin->server_read_task =
1506 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
1507 GNUNET_TIME_UNIT_FOREVER_REL,
1508 plugin->server_stdout_handle, &udp_plugin_server_read, plugin);
1511 udp_sock.desc = NULL;
1514 udp_sock.desc = GNUNET_NETWORK_socket_create (PF_INET, SOCK_DGRAM, 17);
1515 if (NULL == udp_sock.desc)
1517 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp", "socket");
1518 return sockets_created;
1522 memset (&serverAddrv4, 0, sizeof (serverAddrv4));
1523 #if HAVE_SOCKADDR_IN_SIN_LEN
1524 serverAddrv4.sin_len = sizeof (serverAddrv4);
1526 serverAddrv4.sin_family = AF_INET;
1527 serverAddrv4.sin_addr.s_addr = INADDR_ANY;
1528 serverAddrv4.sin_port = htons (plugin->port);
1529 addrlen = sizeof (serverAddrv4);
1530 serverAddr = (struct sockaddr *) &serverAddrv4;
1532 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1534 "Binding to port %d\n", ntohs(serverAddrv4.sin_port));
1536 while (GNUNET_NETWORK_socket_bind (udp_sock.desc, serverAddr, addrlen) !=
1539 serverAddrv4.sin_port = htons (GNUNET_CRYPTO_random_u32(GNUNET_CRYPTO_QUALITY_STRONG, 33537) + 32000); /* Find a good, non-root port */
1541 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1543 "Binding failed, trying new port %d\n", ntohs(serverAddrv4.sin_port));
1546 udp_sock.port = ntohs(serverAddrv4.sin_port);
1551 if ((udp_sock.desc == NULL) && (GNUNET_YES !=
1552 GNUNET_CONFIGURATION_get_value_yesno (plugin->env->cfg, "GNUNETD",
1555 udp_sock.desc = GNUNET_NETWORK_socket_create (PF_INET6, SOCK_DGRAM, 17);
1556 if (udp_sock.desc != NULL)
1558 memset (&serverAddrv6, 0, sizeof (serverAddrv6));
1559 #if HAVE_SOCKADDR_IN_SIN_LEN
1560 serverAddrv6.sin6_len = sizeof (serverAddrv6);
1562 serverAddrv6.sin6_family = AF_INET6;
1563 serverAddrv6.sin6_addr = in6addr_any;
1564 serverAddrv6.sin6_port = htons (plugin->port);
1565 addrlen = sizeof (serverAddrv6);
1566 serverAddr = (struct sockaddr *) &serverAddrv6;
1571 plugin->rs = GNUNET_NETWORK_fdset_create ();
1573 GNUNET_NETWORK_fdset_zero (plugin->rs);
1576 GNUNET_NETWORK_fdset_set (plugin->rs, udp_sock.desc);
1578 plugin->select_task =
1579 GNUNET_SCHEDULER_add_select (plugin->env->sched,
1580 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1581 GNUNET_SCHEDULER_NO_TASK,
1582 GNUNET_TIME_UNIT_FOREVER_REL, plugin->rs,
1583 NULL, &udp_plugin_select, plugin);
1585 return sockets_created;
1591 * Check if the given port is plausible (must be either
1592 * our listen port or our advertised port). If it is
1593 * neither, we return GNUNET_SYSERR.
1595 * @param plugin global variables
1596 * @param in_port port number to check
1597 * @return GNUNET_OK if port is either open_port or adv_port
1600 check_port (struct Plugin *plugin, uint16_t in_port)
1602 if (in_port == plugin->port)
1604 return GNUNET_SYSERR;
1609 * Function that will be called to check if a binary address for this
1610 * plugin is well-formed and corresponds to an address for THIS peer
1611 * (as per our configuration). Naturally, if absolutely necessary,
1612 * plugins can be a bit conservative in their answer, but in general
1613 * plugins should make sure that the address does not redirect
1614 * traffic to a 3rd party that might try to man-in-the-middle our
1617 * @param cls closure, should be our handle to the Plugin
1618 * @param addr pointer to the address
1619 * @param addrlen length of addr
1620 * @return GNUNET_OK if this is a plausible address for this peer
1621 * and transport, GNUNET_SYSERR if not
1625 udp_check_address (void *cls,
1629 struct Plugin *plugin = cls;
1630 struct IPv4UdpAddress *v4;
1631 struct IPv6UdpAddress *v6;
1633 if ((addrlen != sizeof (struct IPv4UdpAddress)) &&
1634 (addrlen != sizeof (struct IPv6UdpAddress)))
1636 GNUNET_break_op (0);
1637 return GNUNET_SYSERR;
1639 if (addrlen == sizeof (struct IPv4UdpAddress))
1641 v4 = (struct IPv4UdpAddress *) addr;
1643 check_port (plugin, ntohs (v4->u_port)))
1644 return GNUNET_SYSERR;
1645 /* FIXME: check IP! */
1649 v6 = (struct IPv6UdpAddress *) addr;
1650 if (IN6_IS_ADDR_LINKLOCAL (&v6->ipv6_addr))
1652 GNUNET_break_op (0);
1653 return GNUNET_SYSERR;
1656 check_port (plugin, ntohs (v6->u6_port)))
1657 return GNUNET_SYSERR;
1658 /* FIXME: check IP! */
1661 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1663 "Informing transport service about my address `%s'.\n",
1664 GNUNET_a2s (addr, addrlen));
1671 * Append our port and forward the result.
1674 append_port (void *cls, const char *hostname)
1676 struct PrettyPrinterContext *ppc = cls;
1679 if (hostname == NULL)
1681 ppc->asc (ppc->asc_cls, NULL);
1685 GNUNET_asprintf (&ret, "%s:%d", hostname, ppc->port);
1686 ppc->asc (ppc->asc_cls, ret);
1692 * Convert the transports address to a nice, human-readable
1695 * @param cls closure
1696 * @param type name of the transport that generated the address
1697 * @param addr one of the addresses of the host, NULL for the last address
1698 * the specific address format depends on the transport
1699 * @param addrlen length of the address
1700 * @param numeric should (IP) addresses be displayed in numeric form?
1701 * @param timeout after how long should we give up?
1702 * @param asc function to call on each string
1703 * @param asc_cls closure for asc
1706 udp_plugin_address_pretty_printer (void *cls,
1711 struct GNUNET_TIME_Relative timeout,
1712 GNUNET_TRANSPORT_AddressStringCallback asc,
1715 struct Plugin *plugin = cls;
1716 const struct sockaddr_in *v4;
1717 const struct sockaddr_in6 *v6;
1718 struct PrettyPrinterContext *ppc;
1720 if ((addrlen != sizeof (struct sockaddr_in)) &&
1721 (addrlen != sizeof (struct sockaddr_in6)))
1723 /* invalid address */
1724 GNUNET_break_op (0);
1725 asc (asc_cls, NULL);
1728 ppc = GNUNET_malloc (sizeof (struct PrettyPrinterContext));
1730 ppc->asc_cls = asc_cls;
1731 if (addrlen == sizeof (struct sockaddr_in))
1733 v4 = (const struct sockaddr_in *) addr;
1734 ppc->port = ntohs (v4->sin_port);
1738 v6 = (const struct sockaddr_in6 *) addr;
1739 ppc->port = ntohs (v6->sin6_port);
1742 GNUNET_RESOLVER_hostname_get (plugin->env->sched,
1746 !numeric, timeout, &append_port, ppc);
1750 * Return the actual path to a file found in the current
1751 * PATH environment variable.
1753 * @param binary the name of the file to find
1756 get_path_from_PATH (char *binary)
1764 p = getenv ("PATH");
1767 path = GNUNET_strdup (p); /* because we write on it */
1768 buf = GNUNET_malloc (strlen (path) + 20);
1771 while (NULL != (end = strchr (pos, ':')))
1774 sprintf (buf, "%s/%s", pos, binary);
1775 if (GNUNET_DISK_file_test (buf) == GNUNET_YES)
1782 sprintf (buf, "%s/%s", pos, binary);
1783 if (GNUNET_DISK_file_test (buf) == GNUNET_YES)
1794 * Check whether the suid bit is set on a file.
1795 * Attempts to find the file using the current
1796 * PATH environment variable as a search path.
1798 * @param binary the name of the file to check
1801 check_gnunet_nat_binary(char *binary)
1803 struct stat statbuf;
1806 p = get_path_from_PATH (binary);
1809 if (0 != STAT (p, &statbuf))
1812 return GNUNET_SYSERR;
1815 if ( (0 != (statbuf.st_mode & S_ISUID)) &&
1816 (statbuf.st_uid == 0) )
1822 * Function called for a quick conversion of the binary address to
1823 * a numeric address. Note that the caller must not free the
1824 * address and that the next call to this function is allowed
1825 * to override the address again.
1827 * @param cls closure
1828 * @param addr binary address
1829 * @param addrlen length of the address
1830 * @return string representing the same address
1833 udp_address_to_string (void *cls,
1837 static char rbuf[INET6_ADDRSTRLEN + 10];
1838 char buf[INET6_ADDRSTRLEN];
1842 const struct IPv4UdpAddress *t4;
1843 const struct IPv6UdpAddress *t6;
1847 if (addrlen == sizeof (struct IPv6UdpAddress))
1851 port = ntohs (t6->u6_port);
1852 memcpy (&a6, &t6->ipv6_addr, sizeof (a6));
1855 else if (addrlen == sizeof (struct IPv4UdpAddress))
1859 port = ntohs (t4->u_port);
1860 memcpy (&a4, &t4->ipv4_addr, sizeof (a4));
1865 inet_ntop (af, sb, buf, INET6_ADDRSTRLEN);
1866 GNUNET_snprintf (rbuf,
1875 * The exported method. Makes the core api available via a global and
1876 * returns the udp transport API.
1879 libgnunet_plugin_transport_udp_init (void *cls)
1881 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
1882 unsigned long long mtu;
1883 unsigned long long port;
1884 struct GNUNET_TRANSPORT_PluginFunctions *api;
1885 struct Plugin *plugin;
1886 struct GNUNET_SERVICE_Context *service;
1887 int sockets_created;
1890 int only_nat_addresses;
1891 char *internal_address;
1892 char *external_address;
1893 struct IPv4UdpAddress v4_address;
1895 service = GNUNET_SERVICE_start ("transport-udp", env->sched, env->cfg);
1896 if (service == NULL)
1898 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "udp", _
1899 ("Failed to start service for `%s' transport plugin.\n"),
1904 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
1908 /* We are behind nat (according to the user) */
1909 if (check_gnunet_nat_binary("gnunet-nat-server") == GNUNET_YES)
1910 behind_nat = GNUNET_YES;
1913 behind_nat = GNUNET_NO;
1914 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "udp", "Configuration specified you are behind a NAT, but gnunet-nat-server is not installed properly (suid bit not set)!\n");
1918 behind_nat = GNUNET_NO; /* We are not behind nat! */
1920 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
1924 if (check_gnunet_nat_binary("gnunet-nat-client") == GNUNET_YES)
1925 allow_nat = GNUNET_YES; /* We will try to connect to NAT'd peers */
1928 allow_nat = GNUNET_NO;
1929 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "udp", "Configuration specified you want to connect to NAT'd peers, but gnunet-nat-client is not installed properly (suid bit not set)!\n");
1934 allow_nat = GNUNET_NO; /* We don't want to try to help NAT'd peers */
1936 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
1938 "ONLY_NAT_ADDRESSES"))
1939 only_nat_addresses = GNUNET_YES; /* We will only report our addresses as NAT'd */
1941 only_nat_addresses = GNUNET_NO; /* We will report our addresses as NAT'd and non-NAT'd */
1943 external_address = NULL;
1944 if (((GNUNET_YES == behind_nat) || (GNUNET_YES == allow_nat)) && (GNUNET_OK !=
1945 GNUNET_CONFIGURATION_get_value_string (env->cfg,
1948 &external_address)))
1950 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
1953 ("Require EXTERNAL_ADDRESS for service `%s' in configuration (either BEHIND_NAT or ALLOW_NAT set to YES)!\n"),
1955 GNUNET_SERVICE_stop (service);
1959 if ((external_address != NULL) && (inet_pton(AF_INET, external_address, &v4_address.ipv4_addr) != 1))
1961 GNUNET_log_from(GNUNET_ERROR_TYPE_WARNING, "udp", "Malformed EXTERNAL_ADDRESS %s given in configuration!\n", external_address);
1964 internal_address = NULL;
1965 if ((GNUNET_YES == behind_nat) && (GNUNET_OK !=
1966 GNUNET_CONFIGURATION_get_value_string (env->cfg,
1969 &internal_address)))
1971 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
1974 ("Require INTERNAL_ADDRESS for service `%s' in configuration!\n"),
1976 GNUNET_SERVICE_stop (service);
1977 GNUNET_free_non_null(external_address);
1981 if ((internal_address != NULL) && (inet_pton(AF_INET, internal_address, &v4_address.ipv4_addr) != 1))
1983 GNUNET_log_from(GNUNET_ERROR_TYPE_WARNING, "udp", "Malformed INTERNAL_ADDRESS %s given in configuration!\n", internal_address);
1987 GNUNET_CONFIGURATION_get_value_number (env->cfg,
1991 port = UDP_NAT_DEFAULT_PORT;
1992 else if (port > 65535)
1994 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING,
1996 _("Given `%s' option is out of range: %llu > %u\n"),
2000 GNUNET_SERVICE_stop (service);
2001 GNUNET_free_non_null(external_address);
2002 GNUNET_free_non_null(internal_address);
2008 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
2010 _("MTU %llu for `%s' is probably too low!\n"), mtu,
2013 plugin = GNUNET_malloc (sizeof (struct Plugin));
2014 plugin->external_address = external_address;
2015 plugin->internal_address = internal_address;
2016 plugin->port = port;
2017 plugin->behind_nat = behind_nat;
2018 plugin->allow_nat = allow_nat;
2019 plugin->only_nat_addresses = only_nat_addresses;
2022 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
2025 api->send = &udp_plugin_send;
2026 api->disconnect = &udp_disconnect;
2027 api->address_pretty_printer = &udp_plugin_address_pretty_printer;
2028 api->address_to_string = &udp_address_to_string;
2029 api->check_address = &udp_check_address;
2031 plugin->service = service;
2033 if (plugin->behind_nat == GNUNET_NO)
2035 GNUNET_OS_network_interfaces_list (&process_interfaces, plugin);
2038 plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (env->sched,
2041 HOSTNAME_RESOLVE_TIMEOUT,
2042 &process_hostname_ips,
2045 if ((plugin->behind_nat == GNUNET_YES) && (inet_pton(AF_INET, plugin->external_address, &v4_address.ipv4_addr) == 1))
2047 v4_address.u_port = htons(0);
2048 plugin->env->notify_address (plugin->env->cls,
2050 &v4_address, sizeof(v4_address), GNUNET_TIME_UNIT_FOREVER_REL);
2052 else if ((plugin->external_address != NULL) && (inet_pton(AF_INET, plugin->external_address, &v4_address.ipv4_addr) == 1))
2054 v4_address.u_port = htons(plugin->port);
2055 plugin->env->notify_address (plugin->env->cls,
2057 &v4_address, sizeof(v4_address), GNUNET_TIME_UNIT_FOREVER_REL);
2060 sockets_created = udp_transport_server_start (plugin);
2062 GNUNET_assert (sockets_created == 1);
2068 libgnunet_plugin_transport_udp_done (void *cls)
2070 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
2071 struct Plugin *plugin = api->cls;
2073 udp_transport_server_stop (plugin);
2074 if (NULL != plugin->hostname_dns)
2076 GNUNET_RESOLVER_request_cancel (plugin->hostname_dns);
2077 plugin->hostname_dns = NULL;
2080 GNUNET_SERVICE_stop (plugin->service);
2082 GNUNET_NETWORK_fdset_destroy (plugin->rs);
2083 GNUNET_free (plugin);
2088 /* end of plugin_transport_udp.c */