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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 sockaddr_in sock_addr;
304 * The port to send this probe to, 0 to choose randomly
312 * Encapsulation of all of the state of the plugin.
319 struct GNUNET_TRANSPORT_PluginEnvironment *env;
322 * Handle to the network service.
324 struct GNUNET_SERVICE_Context *service;
327 * Session of peers with whom we are currently connected
329 struct PeerSession *sessions;
332 * Handle for request of hostname resolution, non-NULL if pending.
334 struct GNUNET_RESOLVER_RequestHandle *hostname_dns;
337 * ID of task used to update our addresses when one expires.
339 GNUNET_SCHEDULER_TaskIdentifier address_update_task;
344 GNUNET_SCHEDULER_TaskIdentifier select_task;
352 * The external address given to us by the user. Must be actual
353 * outside visible address for NAT punching to work.
355 char *external_address;
358 * The internal address given to us by the user (or discovered).
360 char *internal_address;
365 struct GNUNET_NETWORK_FDSet *rs;
368 * stdout pipe handle for the gnunet-nat-server process
370 struct GNUNET_DISK_PipeHandle *server_stdout;
373 * stdout file handle (for reading) for the gnunet-nat-server process
375 const struct GNUNET_DISK_FileHandle *server_stdout_handle;
378 * ID of select gnunet-nat-server stdout read task
380 GNUNET_SCHEDULER_TaskIdentifier server_read_task;
383 * Is this transport configured to be behind a NAT?
388 * Is this transport configured to allow connections to NAT'd peers?
393 * Should this transport advertise only NAT addresses (port set to 0)?
394 * If not, all addresses will be duplicated for NAT punching and regular
397 int only_nat_addresses;
400 * The process id of the server process (if behind NAT)
407 struct UDP_NAT_Probes *probes;
414 /* The network handle */
415 struct GNUNET_NETWORK_Handle *desc;
417 /* The port we bound to */
421 /* *********** globals ************* */
424 * the socket that we transmit all data with
426 static struct UDP_Sock_Info udp_sock;
430 * Forward declaration.
433 udp_probe_continuation (void *cls, const struct GNUNET_PeerIdentity *target, int result);
437 * Disconnect from a remote node. Clean up session if we have one for this peer
439 * @param cls closure for this call (should be handle to Plugin)
440 * @param target the peeridentity of the peer to disconnect
441 * @return GNUNET_OK on success, GNUNET_SYSERR if the operation failed
444 udp_disconnect (void *cls, const struct GNUNET_PeerIdentity *target)
446 /** TODO: Implement! */
451 * Shutdown the server process (stop receiving inbound traffic). Maybe
454 * @param cls Handle to the plugin for this transport
456 * @return returns the number of sockets successfully closed,
457 * should equal the number of sockets successfully opened
460 udp_transport_server_stop (void *cls)
462 struct Plugin *plugin = cls;
467 if (plugin->select_task != GNUNET_SCHEDULER_NO_TASK)
469 GNUNET_SCHEDULER_cancel (plugin->env->sched, plugin->select_task);
470 plugin->select_task = GNUNET_SCHEDULER_NO_TASK;
473 ok = GNUNET_NETWORK_socket_close (udp_sock.desc);
475 udp_sock.desc = NULL;
478 if (plugin->behind_nat == GNUNET_YES)
480 if (0 != PLIBC_KILL (plugin->server_pid, SIGTERM))
482 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "kill");
484 GNUNET_OS_process_wait (plugin->server_pid);
487 if (ret != GNUNET_OK)
488 return GNUNET_SYSERR;
494 find_session (struct Plugin *plugin, const struct GNUNET_PeerIdentity *peer)
496 struct PeerSession *pos;
498 pos = plugin->sessions;
501 if (memcmp(&pos->target, peer, sizeof(struct GNUNET_PeerIdentity)) == 0)
511 * Actually send out the message, assume we've got the address and
512 * send_handle squared away!
515 * @param send_handle which handle to send message on
516 * @param target who should receive this message (ignored by UDP)
517 * @param msgbuf one or more GNUNET_MessageHeader(s) strung together
518 * @param msgbuf_size the size of the msgbuf to send
519 * @param priority how important is the message (ignored by UDP)
520 * @param timeout when should we time out (give up) if we can not transmit?
521 * @param addr the addr to send the message to, needs to be a sockaddr for us
522 * @param addrlen the len of addr
523 * @param cont continuation to call once the message has
524 * been transmitted (or if the transport is ready
525 * for the next transmission call; or if the
526 * peer disconnected...)
527 * @param cont_cls closure for cont
528 * @return the number of bytes written
531 udp_real_send (void *cls,
532 struct GNUNET_NETWORK_Handle *send_handle,
533 const struct GNUNET_PeerIdentity *target,
536 unsigned int priority,
537 struct GNUNET_TIME_Relative timeout,
540 GNUNET_TRANSPORT_TransmitContinuation cont,
543 struct Plugin *plugin = cls;
544 struct UDPMessage *message;
547 struct sockaddr_in a4;
548 struct sockaddr_in6 a6;
549 const struct IPv4UdpAddress *t4;
550 const struct IPv6UdpAddress *t6;
554 if ((addr == NULL) || (addrlen == 0))
557 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
558 ("udp_real_send called without address, returning!\n"));
561 cont (cont_cls, target, GNUNET_SYSERR);
562 return 0; /* Can never send if we don't have an address!! */
565 /* Build the message to be sent */
566 message = GNUNET_malloc (sizeof (struct UDPMessage) + msgbuf_size);
567 ssize = sizeof (struct UDPMessage) + msgbuf_size;
569 message->header.size = htons (ssize);
570 message->header.type = htons (0);
571 memcpy (&message->sender, plugin->env->my_identity,
572 sizeof (struct GNUNET_PeerIdentity));
573 memcpy (&message[1], msgbuf, msgbuf_size);
575 if (addrlen == sizeof (struct IPv6UdpAddress))
578 memset (&a6, 0, sizeof (a6));
579 #if HAVE_SOCKADDR_IN_SIN_LEN
580 a6.sin6_len = sizeof (a6);
582 a6.sin6_family = AF_INET6;
583 a6.sin6_port = t6->u6_port;
584 memcpy (&a6.sin6_addr,
586 sizeof (struct in6_addr));
590 else if (addrlen == sizeof (struct IPv4UdpAddress))
593 memset (&a4, 0, sizeof (a4));
594 #if HAVE_SOCKADDR_IN_SIN_LEN
595 a4.sin_len = sizeof (a4);
597 a4.sin_family = AF_INET;
598 a4.sin_port = t4->u_port;
599 a4.sin_addr.s_addr = t4->ipv4_addr;
609 /* Actually send the message */
611 GNUNET_NETWORK_socket_sendto (send_handle, message, ssize,
617 if (sent == GNUNET_SYSERR)
618 cont (cont_cls, target, GNUNET_SYSERR);
621 cont (cont_cls, target, GNUNET_OK);
625 GNUNET_free (message);
630 * We learned about a peer (possibly behind NAT) so run the
631 * gnunet-nat-client to send dummy ICMP responses
633 * @param plugin the plugin for this transport
634 * @param addr the address of the peer
635 * @param addrlen the length of the address
638 run_gnunet_nat_client (struct Plugin *plugin, const char *addr, size_t addrlen)
640 char inet4[INET_ADDRSTRLEN];
641 char *address_as_string;
642 char *port_as_string;
644 const struct sockaddr *sa = (const struct sockaddr *)addr;
646 if (addrlen < sizeof (struct sockaddr))
648 switch (sa->sa_family)
651 if (addrlen != sizeof (struct sockaddr_in))
653 if (NULL == inet_ntop (AF_INET,
654 &((struct sockaddr_in *) sa)->sin_addr,
655 inet4, INET_ADDRSTRLEN))
657 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
660 address_as_string = GNUNET_strdup (inet4);
667 GNUNET_asprintf(&port_as_string, "%d", plugin->port);
669 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
670 _("Running gnunet-nat-client with arguments: %s %s %d\n"), plugin->external_address, address_as_string, plugin->port);
673 /* Start the server process */
674 pid = GNUNET_OS_start_process(NULL, NULL, "gnunet-nat-client", "gnunet-nat-client", plugin->external_address, address_as_string, port_as_string, NULL);
675 GNUNET_free(address_as_string);
676 GNUNET_free(port_as_string);
677 GNUNET_OS_process_wait (pid);
681 * Function that can be used by the transport service to transmit
682 * a message using the plugin.
685 * @param target who should receive this message (ignored by UDP)
686 * @param msgbuf one or more GNUNET_MessageHeader(s) strung together
687 * @param msgbuf_size the size of the msgbuf to send
688 * @param priority how important is the message (ignored by UDP)
689 * @param timeout when should we time out (give up) if we can not transmit?
690 * @param session identifier used for this session (can be NULL)
691 * @param addr the addr to send the message to, needs to be a sockaddr for us
692 * @param addrlen the len of addr
693 * @param force_address not used, we had better have an address to send to
694 * because we are stateless!!
695 * @param cont continuation to call once the message has
696 * been transmitted (or if the transport is ready
697 * for the next transmission call; or if the
698 * peer disconnected...)
699 * @param cont_cls closure for cont
701 * @return the number of bytes written (may return 0 and the message can
702 * still be transmitted later!)
705 udp_plugin_send (void *cls,
706 const struct GNUNET_PeerIdentity *target,
709 unsigned int priority,
710 struct GNUNET_TIME_Relative timeout,
711 struct Session *session,
715 GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
717 struct Plugin *plugin = cls;
719 struct MessageQueue *temp_message;
720 struct PeerSession *peer_session;
722 const struct IPv4UdpAddress *t4;
724 GNUNET_assert (NULL == session);
725 other_peer_natd = GNUNET_NO;
727 if (addrlen == sizeof(struct IPv4UdpAddress))
730 if (ntohs(t4->u_port) == 0)
731 other_peer_natd = GNUNET_YES;
733 else if (addrlen == sizeof(struct IPv6UdpAddress))
744 if ((other_peer_natd == GNUNET_YES) && (plugin->allow_nat == GNUNET_YES))
746 peer_session = find_session(plugin, target);
747 if (peer_session == NULL) /* We have a new peer to add */
750 * The first time, we can assume we have no knowledge of a
751 * working port for this peer, call the ICMP/UDP message sender
754 peer_session = GNUNET_malloc(sizeof(struct PeerSession));
755 peer_session->connect_addr = GNUNET_malloc(addrlen);
756 memcpy(peer_session->connect_addr, addr, addrlen);
757 peer_session->connect_alen = addrlen;
758 peer_session->plugin = plugin;
759 peer_session->sock = NULL;
760 memcpy(&peer_session->target, target, sizeof(struct GNUNET_PeerIdentity));
761 peer_session->expecting_welcome = GNUNET_YES;
763 peer_session->next = plugin->sessions;
764 plugin->sessions = peer_session;
766 peer_session->messages = GNUNET_malloc(sizeof(struct MessageQueue));
767 peer_session->messages->msgbuf = GNUNET_malloc(msgbuf_size);
768 memcpy(peer_session->messages->msgbuf, msgbuf, msgbuf_size);
769 peer_session->messages->msgbuf_size = msgbuf_size;
770 peer_session->messages->timeout = GNUNET_TIME_relative_to_absolute(timeout);
771 peer_session->messages->cont = cont;
772 peer_session->messages->cont_cls = cont_cls;
774 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
775 _("Other peer is NAT'd, set up peer session for peer %s\n"), GNUNET_i2s(target));
777 run_gnunet_nat_client(plugin, addr, addrlen);
781 if (peer_session->expecting_welcome == GNUNET_NO) /* We are "connected" */
783 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);
785 else /* Haven't gotten a response from this peer, queue message */
787 temp_message = GNUNET_malloc(sizeof(struct MessageQueue));
788 temp_message->msgbuf = GNUNET_malloc(msgbuf_size);
789 memcpy(temp_message->msgbuf, msgbuf, msgbuf_size);
790 temp_message->msgbuf_size = msgbuf_size;
791 temp_message->timeout = GNUNET_TIME_relative_to_absolute(timeout);
792 temp_message->cont = cont;
793 temp_message->cont_cls = cont_cls;
794 temp_message->next = peer_session->messages;
795 peer_session->messages = temp_message;
799 else if (other_peer_natd == GNUNET_NO) /* Other peer not behind a NAT, so we can just send the message as is */
801 sent = udp_real_send(cls, udp_sock.desc, target, msgbuf, msgbuf_size, priority, timeout, addr, addrlen, cont, cont_cls);
803 else /* Other peer is NAT'd, but we don't want to play with them (or can't!) */
804 return GNUNET_SYSERR;
806 /* When GNUNET_SYSERR is returned from udp_real_send, we will still call
807 * the callback so must not return GNUNET_SYSERR!
808 * If we do, then transport context get freed twice. */
809 if (sent == GNUNET_SYSERR)
817 * Add the IP of our network interface to the list of
818 * our external IP addresses.
821 process_interfaces (void *cls,
824 const struct sockaddr *addr, socklen_t addrlen)
826 struct Plugin *plugin = cls;
828 struct IPv4UdpAddress t4;
829 struct IPv6UdpAddress t6;
836 af = addr->sa_family;
839 t4.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
840 if ((plugin->behind_nat == GNUNET_YES) && (plugin->only_nat_addresses == GNUNET_YES))
842 t4.u_port = htons (DEFAULT_NAT_PORT);
844 else if (plugin->behind_nat == GNUNET_YES) /* We are behind NAT, but will advertise NAT and normal addresses */
846 addr_nat = GNUNET_malloc(sizeof(t4));
847 memcpy(addr_nat, &t4, sizeof(t4));
848 t4.u_port = plugin->port;
849 ((struct IPv4UdpAddress *)addr_nat)->u_port = htons(DEFAULT_NAT_PORT);
853 t4.u_port = htons(plugin->port);
858 else if (af == AF_INET6)
861 if (IN6_IS_ADDR_LINKLOCAL (&((struct sockaddr_in6 *) addr)->sin6_addr))
863 /* skip link local addresses */
866 memcpy (&t6.ipv6_addr,
867 &((struct sockaddr_in6 *) addr)->sin6_addr,
868 sizeof (struct in6_addr));
869 if ((plugin->behind_nat == GNUNET_YES) && (plugin->only_nat_addresses == GNUNET_YES))
871 t6.u6_port = htons (0);
873 else if (plugin->behind_nat == GNUNET_YES)
875 addr_nat = GNUNET_malloc(sizeof(t6));
876 memcpy(addr_nat, &t6, sizeof(t6));
877 t6.u6_port = plugin->port;
878 ((struct IPv6UdpAddress *)addr_nat)->u6_port = htons(DEFAULT_NAT_PORT);
882 t6.u6_port = htons (plugin->port);
889 GNUNET_log (GNUNET_ERROR_TYPE_INFO |
890 GNUNET_ERROR_TYPE_BULK,
891 _("Found address `%s' (%s)\n"),
892 GNUNET_a2s (addr, addrlen), name);
894 if (addr_nat != NULL)
896 plugin->env->notify_address (plugin->env->cls,
898 addr_nat, args, GNUNET_TIME_UNIT_FOREVER_REL);
899 GNUNET_log (GNUNET_ERROR_TYPE_INFO |
900 GNUNET_ERROR_TYPE_BULK,
901 _("Found NAT address `%s' (%s)\n"),
902 GNUNET_a2s (addr_nat, args), name);
903 GNUNET_free(addr_nat);
906 plugin->env->notify_address (plugin->env->cls,
908 arg, args, GNUNET_TIME_UNIT_FOREVER_REL);
915 * Function called by the resolver for each address obtained from DNS
916 * for our own hostname. Add the addresses to the list of our
917 * external IP addresses.
920 * @param addr one of the addresses of the host, NULL for the last address
921 * @param addrlen length of the address
924 process_hostname_ips (void *cls,
925 const struct sockaddr *addr, socklen_t addrlen)
927 struct Plugin *plugin = cls;
931 plugin->hostname_dns = NULL;
934 process_interfaces (plugin, "<hostname>", GNUNET_YES, addr, addrlen);
939 * Send UDP probe messages or UDP keepalive messages, depending on the
940 * state of the connection.
942 * @param cls closure for this call (should be the main Plugin)
943 * @param tc task context for running this
946 send_udp_probe_message (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
948 struct UDP_NAT_Probes *probe = cls;
949 struct UDP_NAT_ProbeMessage *message;
950 struct Plugin *plugin = probe->plugin;
952 message = GNUNET_malloc(sizeof(struct UDP_NAT_ProbeMessage));
953 message->header.size = htons(sizeof(struct UDP_NAT_ProbeMessage));
954 message->header.type = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE);
955 /* If they gave us a port, use that. If not, try our port. */
956 if (probe->port != 0)
957 probe->sock_addr.sin_port = htons(probe->port);
959 probe->sock_addr.sin_port = htons(plugin->port);
962 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
963 _("Sending a probe to port %d\n"), ntohs(probe->sock_addr.sin_port));
968 udp_real_send(plugin, udp_sock.desc, NULL,
969 (char *)message, ntohs(message->header.size), 0,
970 GNUNET_TIME_relative_get_unit(),
971 &probe->sock_addr, sizeof(probe->sock_addr),
972 &udp_probe_continuation, probe);
974 GNUNET_free(message);
979 * Continuation for probe sends. If the last probe was sent
980 * "successfully", schedule sending of another one. If not,
984 udp_probe_continuation (void *cls, const struct GNUNET_PeerIdentity *target, int result)
986 struct UDP_NAT_Probes *probe = cls;
987 struct Plugin *plugin = probe->plugin;
989 if ((result == GNUNET_OK) && (probe->count < MAX_PROBES))
992 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
993 _("Scheduling next probe for 10000 milliseconds\n"));
995 probe->task = GNUNET_SCHEDULER_add_delayed(plugin->env->sched, GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MILLISECONDS, 10000), &send_udp_probe_message, probe);
997 else /* Destroy the probe context. */
1000 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1001 _("Sending probe didn't go well...\n"));
1007 * Find probe message by address
1009 * @param plugin the plugin for this transport
1010 * @param address_string the ip address as a string
1012 struct UDP_NAT_Probes *
1013 find_probe(struct Plugin *plugin, char * address_string)
1015 struct UDP_NAT_Probes *pos;
1017 pos = plugin->probes;
1019 if (strcmp(pos->address_string, address_string) == 0)
1027 * @param cls the plugin handle
1028 * @param tc the scheduling context (for rescheduling this function again)
1030 * We have been notified that gnunet-nat-server has written something to stdout.
1031 * Handle the output, then reschedule this function to be called again once
1032 * more is available.
1036 udp_plugin_server_read (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1038 struct Plugin *plugin = cls;
1041 memset(&mybuf, 0, sizeof(mybuf));
1043 struct UDP_NAT_Probes *temp_probe;
1046 struct sockaddr_in in_addr;
1048 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
1051 bytes = GNUNET_DISK_file_read(plugin->server_stdout_handle, &mybuf, sizeof(mybuf));
1056 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1057 _("Finished reading from server stdout with code: %d\n"), bytes);
1064 for (i = 0; i < sizeof(mybuf); i++)
1066 if (mybuf[i] == '\n')
1069 if ((mybuf[i] == ':') && (i + 1 < sizeof(mybuf)))
1072 port_start = &mybuf[i + 1];
1076 if (port_start != NULL)
1077 port = atoi(port_start);
1080 plugin->server_read_task =
1081 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
1082 GNUNET_TIME_UNIT_FOREVER_REL,
1083 plugin->server_stdout_handle, &udp_plugin_server_read, plugin);
1088 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1089 _("nat-server-read read: %s port %d\n"), &mybuf, port);
1093 * We have received an ICMP response, ostensibly from a non-NAT'd peer
1094 * that wants to connect to us! Send a message to establish a connection.
1096 if (inet_pton(AF_INET, &mybuf[0], &in_addr.sin_addr) != 1)
1099 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "udp",
1100 _("nat-server-read malformed address\n"), &mybuf, port);
1102 plugin->server_read_task =
1103 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
1104 GNUNET_TIME_UNIT_FOREVER_REL,
1105 plugin->server_stdout_handle, &udp_plugin_server_read, plugin);
1109 temp_probe = find_probe(plugin, &mybuf[0]);
1111 if (temp_probe == NULL)
1113 temp_probe = GNUNET_malloc(sizeof(struct UDP_NAT_Probes));
1114 temp_probe->address_string = strdup(&mybuf[0]);
1115 temp_probe->sock_addr.sin_family = AF_INET;
1116 GNUNET_assert(inet_pton(AF_INET, &mybuf[0], &temp_probe->sock_addr.sin_addr) == 1);
1117 temp_probe->port = port;
1118 temp_probe->next = plugin->probes;
1119 temp_probe->plugin = plugin;
1120 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);
1121 plugin->probes = temp_probe;
1124 plugin->server_read_task =
1125 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
1126 GNUNET_TIME_UNIT_FOREVER_REL,
1127 plugin->server_stdout_handle, &udp_plugin_server_read, plugin);
1133 * Demultiplexer for UDP NAT messages
1135 * @param plugin the main plugin for this transport
1136 * @param sender from which peer the message was received
1137 * @param currhdr pointer to the header of the message
1138 * @param sender_addr the address from which the message was received
1139 * @param fromlen the length of the address
1140 * @param sockinfo which socket did we receive the message on
1143 udp_demultiplexer(struct Plugin *plugin, struct GNUNET_PeerIdentity *sender,
1144 const struct GNUNET_MessageHeader *currhdr,
1145 const void *sender_addr,
1146 size_t fromlen, struct UDP_Sock_Info *sockinfo)
1148 struct UDP_NAT_ProbeMessageReply *outgoing_probe_reply;
1149 struct UDP_NAT_ProbeMessageConfirmation *outgoing_probe_confirmation;
1151 char addr_buf[INET_ADDRSTRLEN];
1152 struct UDP_NAT_Probes *outgoing_probe;
1153 struct PeerSession *peer_session;
1154 struct MessageQueue *pending_message;
1155 struct MessageQueue *pending_message_temp;
1157 if (memcmp(sender, plugin->env->my_identity, sizeof(struct GNUNET_PeerIdentity)) == 0)
1160 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1161 _("Received a message from myself, dropping!!!\n"));
1166 switch (ntohs(currhdr->type))
1168 case GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE:
1169 /* Send probe reply */
1170 outgoing_probe_reply = GNUNET_malloc(sizeof(struct UDP_NAT_ProbeMessageReply));
1171 outgoing_probe_reply->header.size = htons(sizeof(struct UDP_NAT_ProbeMessageReply));
1172 outgoing_probe_reply->header.type = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE_REPLY);
1175 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1176 _("Received a probe on listen port %d, sent_from port %d\n"), sockinfo->port, ntohs(((struct sockaddr_in *)sender_addr)->sin_port));
1179 udp_real_send(plugin, sockinfo->desc, NULL,
1180 (char *)outgoing_probe_reply,
1181 ntohs(outgoing_probe_reply->header.size), 0,
1182 GNUNET_TIME_relative_get_unit(),
1183 sender_addr, fromlen,
1187 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1188 _("Sent PROBE REPLY to port %d on outgoing port %d\n"), ntohs(((struct sockaddr_in *)sender_addr)->sin_port), sockinfo->port);
1190 GNUNET_free(outgoing_probe_reply);
1192 case GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE_REPLY:
1193 /* Check for existing probe, check ports returned, send confirmation if all is well */
1195 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1196 _("Received PROBE REPLY from port %d on incoming port %d\n"), ntohs(((struct sockaddr_in *)sender_addr)->sin_port), sockinfo->port);
1198 if (sizeof(sender_addr) == sizeof(struct IPv4UdpAddress))
1200 memset(&addr_buf, 0, sizeof(addr_buf));
1201 if (NULL == inet_ntop (AF_INET,
1202 &((struct sockaddr_in *) sender_addr)->sin_addr, addr_buf,
1205 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
1208 outgoing_probe = find_probe(plugin, &addr_buf[0]);
1209 if (outgoing_probe != NULL)
1212 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1213 _("Sending confirmation that we were reached!\n"));
1215 outgoing_probe_confirmation = GNUNET_malloc(sizeof(struct UDP_NAT_ProbeMessageConfirmation));
1216 outgoing_probe_confirmation->header.size = htons(sizeof(struct UDP_NAT_ProbeMessageConfirmation));
1217 outgoing_probe_confirmation->header.type = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE_CONFIRM);
1219 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);
1221 if (outgoing_probe->task != GNUNET_SCHEDULER_NO_TASK)
1223 GNUNET_SCHEDULER_cancel(plugin->env->sched, outgoing_probe->task);
1224 outgoing_probe->task = GNUNET_SCHEDULER_NO_TASK;
1225 /* Schedule task to timeout and remove probe if confirmation not received */
1227 GNUNET_free(outgoing_probe_confirmation);
1232 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1233 _("Received a probe reply, but have no record of a sent probe!\n"));
1238 case GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE_CONFIRM:
1239 peer_session = find_session(plugin, sender);
1241 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1242 _("Looking up peer session for peer %s\n"), GNUNET_i2s(sender));
1244 if (peer_session == NULL) /* Shouldn't this NOT happen? */
1247 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp",
1248 _("Peer not in list, adding (THIS MAY BE A MISTAKE) %s\n"), GNUNET_i2s(sender));
1250 peer_session = GNUNET_malloc(sizeof(struct PeerSession));
1251 peer_session->connect_addr = GNUNET_malloc(fromlen);
1252 memcpy(peer_session->connect_addr, sender_addr, fromlen);
1253 peer_session->connect_alen = fromlen;
1254 peer_session->plugin = plugin;
1255 peer_session->sock = sockinfo->desc;
1256 memcpy(&peer_session->target, sender, sizeof(struct GNUNET_PeerIdentity));
1257 peer_session->expecting_welcome = GNUNET_NO;
1259 peer_session->next = plugin->sessions;
1260 plugin->sessions = peer_session;
1262 peer_session->messages = NULL;
1264 else if (peer_session->expecting_welcome == GNUNET_YES)
1266 peer_session->expecting_welcome = GNUNET_NO;
1267 peer_session->sock = sockinfo->desc;
1268 ((struct sockaddr_in *)peer_session->connect_addr)->sin_port = ((struct sockaddr_in *) sender_addr)->sin_port;
1270 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1271 _("Received a probe confirmation, will send to peer on port %d\n"), ntohs(((struct sockaddr_in *)peer_session->connect_addr)->sin_port));
1273 if (peer_session->messages != NULL)
1276 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1277 _("Received a probe confirmation, sending queued messages.\n"));
1279 pending_message = peer_session->messages;
1281 while (pending_message != NULL)
1284 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1285 _("sending queued message %d\n"), count);
1287 udp_real_send(plugin, peer_session->sock, &peer_session->target, pending_message->msgbuf, pending_message->msgbuf_size, 0, GNUNET_TIME_relative_get_unit(), peer_session->connect_addr, peer_session->connect_alen, pending_message->cont, pending_message->cont_cls);
1288 pending_message_temp = pending_message;
1289 pending_message = pending_message->next;
1290 GNUNET_free(pending_message_temp->msgbuf);
1291 GNUNET_free(pending_message_temp);
1293 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1294 _("finished sending queued message %d\n"), count);
1304 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
1305 _("Received probe confirmation for already confirmed peer!\n"));
1308 /* Received confirmation, add peer with address/port specified */
1310 case GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_NAT_PROBE_KEEPALIVE:
1311 /* Once we've sent NAT_PROBE_CONFIRM change to sending keepalives */
1312 /* If we receive these just ignore! */
1315 plugin->env->receive (plugin->env->cls, sender, currhdr, UDP_DIRECT_DISTANCE,
1316 NULL, sender_addr, fromlen);
1323 * @param cls the plugin handle
1324 * @param tc the scheduling context (for rescheduling this function again)
1326 * We have been notified that our writeset has something to read. We don't
1327 * know which socket needs to be read, so we have to check each one
1328 * Then reschedule this function to be called again once more is available.
1332 udp_plugin_select (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1334 struct Plugin *plugin = cls;
1336 struct UDPMessage *msg;
1337 struct GNUNET_PeerIdentity *sender;
1338 unsigned int buflen;
1346 const struct GNUNET_MessageHeader *currhdr;
1347 struct IPv4UdpAddress t4;
1348 struct IPv6UdpAddress t6;
1349 const struct sockaddr_in *s4;
1350 const struct sockaddr_in6 *s6;
1355 plugin->select_task = GNUNET_SCHEDULER_NO_TASK;
1357 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
1363 buflen = GNUNET_NETWORK_socket_recvfrom_amount (udp_sock.desc);
1365 if (buflen == GNUNET_NO)
1368 buf = GNUNET_malloc (buflen);
1369 fromlen = sizeof (addr);
1370 memset (&addr, 0, sizeof(addr));
1372 GNUNET_NETWORK_socket_recvfrom (udp_sock.desc, buf, buflen,
1373 (struct sockaddr *)&addr, &fromlen);
1375 if (fromlen == sizeof (struct sockaddr_in))
1377 s4 = (const struct sockaddr_in*) &addr;
1378 t4.u_port = s4->sin_port;
1379 t4.ipv4_addr = s4->sin_addr.s_addr;
1381 calen = sizeof (t4);
1383 else if (fromlen == sizeof (struct sockaddr_in6))
1385 s6 = (const struct sockaddr_in6*) &addr;
1386 t6.u6_port = s6->sin6_port;
1387 memcpy (&t6.ipv6_addr,
1389 sizeof (struct in6_addr));
1391 calen = sizeof (t6);
1401 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
1402 ("socket_recv returned %u, src_addr_len is %u\n"), ret,
1411 msg = (struct UDPMessage *) buf;
1414 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
1415 ("header reports message size of %d, type %d\n"),
1416 ntohs (msg->header.size), ntohs (msg->header.type));
1418 if (ntohs (msg->header.size) < sizeof (struct UDPMessage))
1424 msgbuf = (char *)&msg[1];
1425 sender = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
1426 memcpy (sender, &msg->sender, sizeof (struct GNUNET_PeerIdentity));
1430 tsize = ntohs (msg->header.size) - sizeof(struct UDPMessage);
1432 while (offset < tsize)
1434 currhdr = (struct GNUNET_MessageHeader *)&msgbuf[offset];
1436 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
1437 ("processing msg %d: type %d, size %d at offset %d\n"),
1438 count, ntohs(currhdr->type), ntohs(currhdr->size), offset);
1440 udp_demultiplexer(plugin, sender, currhdr, ca, calen, &udp_sock);
1442 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
1443 ("processing done msg %d: type %d, size %d at offset %d\n"),
1444 count, ntohs(currhdr->type), ntohs(currhdr->size), offset);
1446 offset += ntohs(currhdr->size);
1449 GNUNET_free_non_null (buf);
1450 GNUNET_free_non_null (sender);
1453 plugin->select_task =
1454 GNUNET_SCHEDULER_add_select (plugin->env->sched,
1455 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1456 GNUNET_SCHEDULER_NO_TASK,
1457 GNUNET_TIME_UNIT_FOREVER_REL, plugin->rs,
1458 NULL, &udp_plugin_select, plugin);
1463 * Create a slew of UDP sockets. If possible, use IPv6, otherwise
1466 * @param cls closure for server start, should be a struct Plugin *
1468 * @return number of sockets created or GNUNET_SYSERR on error
1471 udp_transport_server_start (void *cls)
1473 struct Plugin *plugin = cls;
1474 struct sockaddr_in serverAddrv4;
1475 struct sockaddr_in6 serverAddrv6;
1476 struct sockaddr *serverAddr;
1478 int sockets_created;
1480 sockets_created = 0;
1482 if (plugin->behind_nat == GNUNET_YES)
1484 /* Pipe to read from started processes stdout (on read end) */
1485 plugin->server_stdout = GNUNET_DISK_pipe(GNUNET_YES);
1486 if (plugin->server_stdout == NULL)
1487 return sockets_created;
1489 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1491 "Starting gnunet-nat-server process cmd: %s %s\n", "gnunet-nat-server", plugin->internal_address);
1493 /* Start the server process */
1494 plugin->server_pid = GNUNET_OS_start_process(NULL, plugin->server_stdout, "gnunet-nat-server", "gnunet-nat-server", plugin->internal_address, NULL);
1495 if (plugin->server_pid == GNUNET_SYSERR)
1498 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1500 "Failed to start gnunet-nat-server process\n");
1502 return GNUNET_SYSERR;
1504 /* Close the write end of the read pipe */
1505 GNUNET_DISK_pipe_close_end(plugin->server_stdout, GNUNET_DISK_PIPE_END_WRITE);
1507 plugin->server_stdout_handle = GNUNET_DISK_pipe_handle(plugin->server_stdout, GNUNET_DISK_PIPE_END_READ);
1508 plugin->server_read_task =
1509 GNUNET_SCHEDULER_add_read_file (plugin->env->sched,
1510 GNUNET_TIME_UNIT_FOREVER_REL,
1511 plugin->server_stdout_handle, &udp_plugin_server_read, plugin);
1514 udp_sock.desc = NULL;
1517 udp_sock.desc = GNUNET_NETWORK_socket_create (PF_INET, SOCK_DGRAM, 17);
1518 if (NULL == udp_sock.desc)
1520 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp", "socket");
1521 return sockets_created;
1525 memset (&serverAddrv4, 0, sizeof (serverAddrv4));
1526 #if HAVE_SOCKADDR_IN_SIN_LEN
1527 serverAddrv4.sin_len = sizeof (serverAddrv4);
1529 serverAddrv4.sin_family = AF_INET;
1530 serverAddrv4.sin_addr.s_addr = INADDR_ANY;
1531 serverAddrv4.sin_port = htons (plugin->port);
1532 addrlen = sizeof (serverAddrv4);
1533 serverAddr = (struct sockaddr *) &serverAddrv4;
1535 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1537 "Binding to port %d\n", ntohs(serverAddrv4.sin_port));
1539 while (GNUNET_NETWORK_socket_bind (udp_sock.desc, serverAddr, addrlen) !=
1542 serverAddrv4.sin_port = htons (GNUNET_CRYPTO_random_u32(GNUNET_CRYPTO_QUALITY_STRONG, 33537) + 32000); /* Find a good, non-root port */
1544 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1546 "Binding failed, trying new port %d\n", ntohs(serverAddrv4.sin_port));
1549 udp_sock.port = ntohs(serverAddrv4.sin_port);
1554 if ((udp_sock.desc == NULL) && (GNUNET_YES !=
1555 GNUNET_CONFIGURATION_get_value_yesno (plugin->env->cfg, "GNUNETD",
1558 udp_sock.desc = GNUNET_NETWORK_socket_create (PF_INET6, SOCK_DGRAM, 17);
1559 if (udp_sock.desc != NULL)
1561 memset (&serverAddrv6, 0, sizeof (serverAddrv6));
1562 #if HAVE_SOCKADDR_IN_SIN_LEN
1563 serverAddrv6.sin6_len = sizeof (serverAddrv6);
1565 serverAddrv6.sin6_family = AF_INET6;
1566 serverAddrv6.sin6_addr = in6addr_any;
1567 serverAddrv6.sin6_port = htons (plugin->port);
1568 addrlen = sizeof (serverAddrv6);
1569 serverAddr = (struct sockaddr *) &serverAddrv6;
1574 plugin->rs = GNUNET_NETWORK_fdset_create ();
1576 GNUNET_NETWORK_fdset_zero (plugin->rs);
1579 GNUNET_NETWORK_fdset_set (plugin->rs, udp_sock.desc);
1581 plugin->select_task =
1582 GNUNET_SCHEDULER_add_select (plugin->env->sched,
1583 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1584 GNUNET_SCHEDULER_NO_TASK,
1585 GNUNET_TIME_UNIT_FOREVER_REL, plugin->rs,
1586 NULL, &udp_plugin_select, plugin);
1588 return sockets_created;
1593 * Another peer has suggested an address for this peer and transport
1594 * plugin. Check that this could be a valid address. This function
1595 * is not expected to 'validate' the address in the sense of trying to
1596 * connect to it but simply to see if the binary format is technically
1597 * legal for establishing a connection.
1599 * @param cls closure, should be our handle to the Plugin
1600 * @param addr pointer to the address, may be modified (slightly)
1601 * @param addrlen length of addr
1602 * @return GNUNET_OK if this is a plausible address for this peer
1603 * and transport, GNUNET_SYSERR if not
1607 udp_check_address (void *cls, void *addr, size_t addrlen)
1609 struct Plugin *plugin = cls;
1610 char buf[sizeof (struct sockaddr_in6)];
1612 struct sockaddr_in *v4;
1613 struct sockaddr_in6 *v6;
1615 if ((addrlen != sizeof (struct sockaddr_in)) &&
1616 (addrlen != sizeof (struct sockaddr_in6)))
1618 GNUNET_break_op (0);
1619 return GNUNET_SYSERR;
1621 memcpy (buf, addr, sizeof (struct sockaddr_in6));
1622 if (addrlen == sizeof (struct sockaddr_in))
1624 v4 = (struct sockaddr_in *) buf;
1625 v4->sin_port = htons (plugin->port);
1629 v6 = (struct sockaddr_in6 *) buf;
1630 v6->sin6_port = htons (plugin->port);
1634 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
1636 "Informing transport service about my address `%s'.\n",
1637 GNUNET_a2s (addr, addrlen));
1644 * Append our port and forward the result.
1647 append_port (void *cls, const char *hostname)
1649 struct PrettyPrinterContext *ppc = cls;
1652 if (hostname == NULL)
1654 ppc->asc (ppc->asc_cls, NULL);
1658 GNUNET_asprintf (&ret, "%s:%d", hostname, ppc->port);
1659 ppc->asc (ppc->asc_cls, ret);
1665 * Convert the transports address to a nice, human-readable
1668 * @param cls closure
1669 * @param type name of the transport that generated the address
1670 * @param addr one of the addresses of the host, NULL for the last address
1671 * the specific address format depends on the transport
1672 * @param addrlen length of the address
1673 * @param numeric should (IP) addresses be displayed in numeric form?
1674 * @param timeout after how long should we give up?
1675 * @param asc function to call on each string
1676 * @param asc_cls closure for asc
1679 udp_plugin_address_pretty_printer (void *cls,
1684 struct GNUNET_TIME_Relative timeout,
1685 GNUNET_TRANSPORT_AddressStringCallback asc,
1688 struct Plugin *plugin = cls;
1689 const struct sockaddr_in *v4;
1690 const struct sockaddr_in6 *v6;
1691 struct PrettyPrinterContext *ppc;
1693 if ((addrlen != sizeof (struct sockaddr_in)) &&
1694 (addrlen != sizeof (struct sockaddr_in6)))
1696 /* invalid address */
1697 GNUNET_break_op (0);
1698 asc (asc_cls, NULL);
1701 ppc = GNUNET_malloc (sizeof (struct PrettyPrinterContext));
1703 ppc->asc_cls = asc_cls;
1704 if (addrlen == sizeof (struct sockaddr_in))
1706 v4 = (const struct sockaddr_in *) addr;
1707 ppc->port = ntohs (v4->sin_port);
1711 v6 = (const struct sockaddr_in6 *) addr;
1712 ppc->port = ntohs (v6->sin6_port);
1715 GNUNET_RESOLVER_hostname_get (plugin->env->sched,
1719 !numeric, timeout, &append_port, ppc);
1723 * Return the actual path to a file found in the current
1724 * PATH environment variable.
1726 * @param binary the name of the file to find
1729 get_path_from_PATH (char *binary)
1737 p = getenv ("PATH");
1740 path = GNUNET_strdup (p); /* because we write on it */
1741 buf = GNUNET_malloc (strlen (path) + 20);
1744 while (NULL != (end = strchr (pos, ':')))
1747 sprintf (buf, "%s/%s", pos, binary);
1748 if (GNUNET_DISK_file_test (buf) == GNUNET_YES)
1755 sprintf (buf, "%s/%s", pos, binary);
1756 if (GNUNET_DISK_file_test (buf) == GNUNET_YES)
1767 * Check whether the suid bit is set on a file.
1768 * Attempts to find the file using the current
1769 * PATH environment variable as a search path.
1771 * @param binary the name of the file to check
1774 check_gnunet_nat_binary(char *binary)
1776 struct stat statbuf;
1779 p = get_path_from_PATH (binary);
1782 if (0 != STAT (p, &statbuf))
1785 return GNUNET_SYSERR;
1788 if ( (0 != (statbuf.st_mode & S_ISUID)) &&
1789 (statbuf.st_uid == 0) )
1795 * Function called for a quick conversion of the binary address to
1796 * a numeric address. Note that the caller must not free the
1797 * address and that the next call to this function is allowed
1798 * to override the address again.
1800 * @param cls closure
1801 * @param addr binary address
1802 * @param addrlen length of the address
1803 * @return string representing the same address
1806 udp_address_to_string (void *cls,
1810 static char rbuf[INET6_ADDRSTRLEN + 10];
1811 char buf[INET6_ADDRSTRLEN];
1815 const struct IPv4UdpAddress *t4;
1816 const struct IPv6UdpAddress *t6;
1820 if (addrlen == sizeof (struct IPv6UdpAddress))
1824 port = ntohs (t6->u6_port);
1825 memcpy (&a6, &t6->ipv6_addr, sizeof (a6));
1828 else if (addrlen == sizeof (struct IPv4UdpAddress))
1832 port = ntohs (t4->u_port);
1833 memcpy (&a4, &t4->ipv4_addr, sizeof (a4));
1838 inet_ntop (af, sb, buf, INET6_ADDRSTRLEN);
1839 GNUNET_snprintf (rbuf,
1848 * The exported method. Makes the core api available via a global and
1849 * returns the udp transport API.
1852 libgnunet_plugin_transport_udp_init (void *cls)
1854 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
1855 unsigned long long mtu;
1856 unsigned long long port;
1857 struct GNUNET_TRANSPORT_PluginFunctions *api;
1858 struct Plugin *plugin;
1859 struct GNUNET_SERVICE_Context *service;
1860 int sockets_created;
1863 int only_nat_addresses;
1864 char *internal_address;
1865 char *external_address;
1866 struct IPv4UdpAddress v4_address;
1868 service = GNUNET_SERVICE_start ("transport-udp", env->sched, env->cfg);
1869 if (service == NULL)
1871 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "udp", _
1872 ("Failed to start service for `%s' transport plugin.\n"),
1877 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
1881 /* We are behind nat (according to the user) */
1882 if (check_gnunet_nat_binary("gnunet-nat-server") == GNUNET_YES)
1883 behind_nat = GNUNET_YES;
1886 behind_nat = GNUNET_NO;
1887 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");
1891 behind_nat = GNUNET_NO; /* We are not behind nat! */
1893 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
1897 if (check_gnunet_nat_binary("gnunet-nat-client") == GNUNET_YES)
1898 allow_nat = GNUNET_YES; /* We will try to connect to NAT'd peers */
1901 allow_nat = GNUNET_NO;
1902 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");
1907 allow_nat = GNUNET_NO; /* We don't want to try to help NAT'd peers */
1909 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg,
1911 "ONLY_NAT_ADDRESSES"))
1912 only_nat_addresses = GNUNET_YES; /* We will only report our addresses as NAT'd */
1914 only_nat_addresses = GNUNET_NO; /* We will report our addresses as NAT'd and non-NAT'd */
1916 external_address = NULL;
1917 if (((GNUNET_YES == behind_nat) || (GNUNET_YES == allow_nat)) && (GNUNET_OK !=
1918 GNUNET_CONFIGURATION_get_value_string (env->cfg,
1921 &external_address)))
1923 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
1926 ("Require EXTERNAL_ADDRESS for service `%s' in configuration (either BEHIND_NAT or ALLOW_NAT set to YES)!\n"),
1928 GNUNET_SERVICE_stop (service);
1932 if ((external_address != NULL) && (inet_pton(AF_INET, external_address, &v4_address.ipv4_addr) != 1))
1934 GNUNET_log_from(GNUNET_ERROR_TYPE_WARNING, "udp", "Malformed EXTERNAL_ADDRESS %s given in configuration!\n", external_address);
1937 internal_address = NULL;
1938 if ((GNUNET_YES == behind_nat) && (GNUNET_OK !=
1939 GNUNET_CONFIGURATION_get_value_string (env->cfg,
1942 &internal_address)))
1944 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
1947 ("Require INTERNAL_ADDRESS for service `%s' in configuration!\n"),
1949 GNUNET_SERVICE_stop (service);
1950 GNUNET_free_non_null(external_address);
1954 if ((internal_address != NULL) && (inet_pton(AF_INET, internal_address, &v4_address.ipv4_addr) != 1))
1956 GNUNET_log_from(GNUNET_ERROR_TYPE_WARNING, "udp", "Malformed INTERNAL_ADDRESS %s given in configuration!\n", internal_address);
1960 GNUNET_CONFIGURATION_get_value_number (env->cfg,
1964 port = UDP_NAT_DEFAULT_PORT;
1965 else if (port > 65535)
1967 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING,
1969 _("Given `%s' option is out of range: %llu > %u\n"),
1973 GNUNET_SERVICE_stop (service);
1974 GNUNET_free_non_null(external_address);
1975 GNUNET_free_non_null(internal_address);
1981 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
1983 _("MTU %llu for `%s' is probably too low!\n"), mtu,
1986 plugin = GNUNET_malloc (sizeof (struct Plugin));
1987 plugin->external_address = external_address;
1988 plugin->internal_address = internal_address;
1989 plugin->port = port;
1990 plugin->behind_nat = behind_nat;
1991 plugin->allow_nat = allow_nat;
1992 plugin->only_nat_addresses = only_nat_addresses;
1995 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
1998 api->send = &udp_plugin_send;
1999 api->disconnect = &udp_disconnect;
2000 api->address_pretty_printer = &udp_plugin_address_pretty_printer;
2001 api->address_to_string = &udp_address_to_string;
2002 api->check_address = &udp_check_address;
2004 plugin->service = service;
2006 if (plugin->behind_nat == GNUNET_NO)
2008 GNUNET_OS_network_interfaces_list (&process_interfaces, plugin);
2011 plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (env->sched,
2014 HOSTNAME_RESOLVE_TIMEOUT,
2015 &process_hostname_ips,
2018 if ((plugin->behind_nat == GNUNET_YES) && (inet_pton(AF_INET, plugin->external_address, &v4_address.ipv4_addr) == 1))
2020 v4_address.u_port = htons(0);
2021 plugin->env->notify_address (plugin->env->cls,
2023 &v4_address, sizeof(v4_address), GNUNET_TIME_UNIT_FOREVER_REL);
2025 else if ((plugin->external_address != NULL) && (inet_pton(AF_INET, plugin->external_address, &v4_address.ipv4_addr) == 1))
2027 v4_address.u_port = htons(plugin->port);
2028 plugin->env->notify_address (plugin->env->cls,
2030 &v4_address, sizeof(v4_address), GNUNET_TIME_UNIT_FOREVER_REL);
2033 sockets_created = udp_transport_server_start (plugin);
2035 GNUNET_assert (sockets_created == 1);
2041 libgnunet_plugin_transport_udp_done (void *cls)
2043 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
2044 struct Plugin *plugin = api->cls;
2046 udp_transport_server_stop (plugin);
2047 if (NULL != plugin->hostname_dns)
2049 GNUNET_RESOLVER_request_cancel (plugin->hostname_dns);
2050 plugin->hostname_dns = NULL;
2053 GNUNET_SERVICE_stop (plugin->service);
2055 GNUNET_NETWORK_fdset_destroy (plugin->rs);
2056 GNUNET_free (plugin);
2061 /* end of plugin_transport_udp.c */