2 This file is part of GNUnet
3 (C) 2010 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file transport/plugin_transport_udp.c
23 * @brief Implementation of the UDP transport service
24 * @author Christian Grothoff
25 * @author Nathan Evans
29 #include "gnunet_hello_lib.h"
30 #include "gnunet_connection_lib.h"
31 #include "gnunet_os_lib.h"
32 #include "gnunet_peerinfo_service.h"
33 #include "gnunet_protocols.h"
34 #include "gnunet_resolver_service.h"
35 #include "gnunet_server_lib.h"
36 #include "gnunet_service_lib.h"
37 #include "gnunet_signatures.h"
38 #include "gnunet_statistics_service.h"
39 #include "gnunet_transport_service.h"
40 #include "plugin_transport.h"
41 #include "transport.h"
43 #define DEBUG_UDP GNUNET_NO
46 * Transport cost to peer, always 1 for UDP (direct connection)
48 #define UDP_DIRECT_DISTANCE 1
51 * How long until we give up on transmitting the welcome message?
53 #define HOSTNAME_RESOLVE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
57 * Message-Packet header.
62 * size of the message, in bytes, including this header.
64 struct GNUNET_MessageHeader header;
67 * What is the identity of the sender (GNUNET_hash of public key)
69 struct GNUNET_PeerIdentity sender;
75 * Network format for IPv4 addresses.
80 * IPv4 address, in network byte order.
85 * Port number, in network byte order.
93 * Network format for IPv6 addresses.
100 unsigned char ipv6_addr[16];
103 * Port number, in network byte order.
113 struct PrettyPrinterContext
118 GNUNET_TRANSPORT_AddressStringCallback asc;
133 * Encapsulation of all of the state of the plugin.
140 struct GNUNET_TRANSPORT_PluginEnvironment *env;
143 * Handle to the network service.
145 struct GNUNET_SERVICE_Context *service;
148 * Handle for request of hostname resolution, non-NULL if pending.
150 struct GNUNET_RESOLVER_RequestHandle *hostname_dns;
155 struct GNUNET_NETWORK_FDSet *rs;
158 * ID of task used to update our addresses when one expires.
160 GNUNET_SCHEDULER_TaskIdentifier address_update_task;
165 GNUNET_SCHEDULER_TaskIdentifier select_task;
168 * Port that we are actually listening on.
173 * Port that the user said we would have visible to the
180 /* *********** globals ************* */
183 * The socket that we transmit all data with
185 static struct GNUNET_NETWORK_Handle *udp_sock;
188 * Disconnect from a remote node.
190 * @param cls closure ('struct Plugin'), unused
191 * @param target peer do disconnect
192 * @return GNUNET_OK on success, GNUNET_SYSERR if the operation failed
195 udp_disconnect (void *cls,
196 const struct GNUNET_PeerIdentity *target)
198 /* nothing to do, UDP is stateless */
202 * Shutdown the server process (stop receiving inbound traffic). Maybe
205 * @param cls closure, the 'struct Plugin*'
208 udp_transport_server_stop (void *cls)
210 struct Plugin *plugin = cls;
213 GNUNET_assert (udp_sock != NULL);
214 if (plugin->select_task != GNUNET_SCHEDULER_NO_TASK)
216 GNUNET_SCHEDULER_cancel (plugin->env->sched, plugin->select_task);
217 plugin->select_task = GNUNET_SCHEDULER_NO_TASK;
220 ret = GNUNET_NETWORK_socket_close (udp_sock);
221 if (ret != GNUNET_SYSERR)
227 * Function that can be used by the transport service to transmit
228 * a message using the plugin.
230 * @param cls closure, the 'struct Plugin*'
231 * @param target who should receive this message (ignored by UDP)
232 * @param msgbuf one or more GNUNET_MessageHeader(s) strung together
233 * @param msgbuf_size the size of the msgbuf to send
234 * @param priority how important is the message (ignored by UDP)
235 * @param timeout when should we time out (give up) if we can not transmit?
236 * @param session which session must be used (always NULL for UDP)
237 * @param addr the addr to send the message to, needs to be a sockaddr for us
238 * @param addrlen the len of addr
239 * @param force_address GNUNET_YES if the plugin MUST use the given address,
240 * GNUNET_NO means the plugin may use any other address and
241 * GNUNET_SYSERR means that only reliable existing
242 * bi-directional connections should be used (regardless
244 * @param cont continuation to call once the message has
245 * been transmitted (or if the transport is ready
246 * for the next transmission call; or if the
247 * peer disconnected...)
248 * @param cont_cls closure for cont
250 * @return the number of bytes written, -1 on error (in this case, cont is not called)
253 udp_plugin_send (void *cls,
254 const struct GNUNET_PeerIdentity *target,
257 unsigned int priority,
258 struct GNUNET_TIME_Relative timeout,
259 struct Session *session,
263 GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
265 struct Plugin *plugin = cls;
266 struct UDPMessage *message;
272 struct sockaddr_in a4;
273 struct sockaddr_in6 a6;
274 const struct IPv4UdpAddress *t4;
275 const struct IPv6UdpAddress *t6;
277 GNUNET_assert (NULL == session);
278 GNUNET_assert(udp_sock != NULL);
279 if ( (addr == NULL) || (addrlen == 0) )
282 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
283 ("udp_plugin_send called without address, returning!\n"));
285 return -1; /* Can never send if we don't have an address!! */
287 if (force_address == GNUNET_SYSERR)
288 return -1; /* never reliable */
290 if (addrlen == sizeof (struct IPv6UdpAddress))
294 memset (&a6, 0, sizeof (a6));
295 #if HAVE_SOCKADDR_IN_SIN_LEN
296 a6.sin6_len = sizeof (a6);
298 a6.sin6_family = AF_INET6;
299 a6.sin6_port = t6->u6_port;
300 memcpy (a6.sin6_addr.s6_addr,
306 else if (addrlen == sizeof (struct IPv4UdpAddress))
310 memset (&a4, 0, sizeof (a4));
311 #if HAVE_SOCKADDR_IN_SIN_LEN
312 a4.sin_len = sizeof (a4);
314 a4.sin_family = AF_INET;
315 a4.sin_port = t4->u_port;
316 a4.sin_addr.s_addr = t4->ipv4_addr;
326 /* Build the message to be sent */
327 message = GNUNET_malloc (sizeof (struct UDPMessage) + msgbuf_size);
328 ssize = sizeof (struct UDPMessage) + msgbuf_size;
331 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp",
332 "In udp_send, ssize is %d, sending message to `%s'\n",
334 GNUNET_a2s(sb, sbs));
336 message->header.size = htons (ssize);
337 message->header.type = htons (0);
338 memcpy (&message->sender, plugin->env->my_identity,
339 sizeof (struct GNUNET_PeerIdentity));
340 memcpy (&message[1], msgbuf, msgbuf_size);
342 GNUNET_NETWORK_socket_sendto (udp_sock, message, ssize,
344 if ( (cont != NULL) &&
346 cont (cont_cls, target, GNUNET_OK);
347 GNUNET_free (message);
353 * Add the IP of our network interface to the list of
354 * our external IP addresses.
356 * @param cls closure (the 'struct Plugin*')
357 * @param name name of the interface (can be NULL for unknown)
358 * @param isDefault is this presumably the default interface
359 * @param addr address of this interface (can be NULL for unknown or unassigned)
360 * @param addrlen length of the address
361 * @return GNUNET_OK to continue iterating
364 process_interfaces (void *cls,
367 const struct sockaddr *addr, socklen_t addrlen)
369 struct Plugin *plugin = cls;
371 struct IPv4UdpAddress t4;
372 struct IPv6UdpAddress t6;
376 af = addr->sa_family;
379 t4.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
380 t4.u_port = htons (plugin->adv_port);
384 else if (af == AF_INET6)
386 memcpy (t6.ipv6_addr,
387 ((struct sockaddr_in6 *) addr)->sin6_addr.s6_addr,
389 t6.u6_port = htons (plugin->adv_port);
398 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO |
399 GNUNET_ERROR_TYPE_BULK,
401 _("Found address `%s' (%s)\n"),
402 GNUNET_a2s (addr, addrlen),
404 plugin->env->notify_address (plugin->env->cls,
406 arg, args, GNUNET_TIME_UNIT_FOREVER_REL);
412 * Function called by the resolver for each address obtained from DNS
413 * for our own hostname. Add the addresses to the list of our
414 * external IP addresses.
417 * @param addr one of the addresses of the host, NULL for the last address
418 * @param addrlen length of the address
421 process_hostname_ips (void *cls,
422 const struct sockaddr *addr, socklen_t addrlen)
424 struct Plugin *plugin = cls;
428 plugin->hostname_dns = NULL;
431 process_interfaces (plugin, "<hostname>", GNUNET_YES, addr, addrlen);
436 * @param cls the plugin handle
437 * @param tc the scheduling context (for rescheduling this function again)
439 * We have been notified that our writeset has something to read. Presumably
440 * select has been called already, so we can go ahead and start reading from
441 * the socket immediately. Then we check if there is more to be read by
442 * calling select ourselves while there is stuff on the wire. Then reschedule
443 * this function to be called again once more is available.
447 udp_plugin_select (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
449 struct Plugin *plugin = cls;
451 struct UDPMessage *msg;
452 struct GNUNET_PeerIdentity *sender;
455 struct sockaddr_storage addr;
461 const struct GNUNET_MessageHeader *currhdr;
462 struct IPv4UdpAddress t4;
463 struct IPv6UdpAddress t6;
464 const struct sockaddr_in *s4;
465 const struct sockaddr_in6 *s6;
470 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
471 ("entered select...\n"));
474 buflen = GNUNET_NETWORK_socket_recvfrom_amount (udp_sock);
477 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
478 ("we expect to read %u bytes\n"), buflen);
481 if (buflen == GNUNET_NO)
484 buf = GNUNET_malloc (buflen);
485 fromlen = sizeof (addr);
487 memset (&addr, 0, fromlen);
489 GNUNET_NETWORK_socket_recvfrom (udp_sock, buf, buflen,
490 (struct sockaddr *) &addr, &fromlen);
493 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
494 ("socket_recv returned %u, src_addr_len is %u\n"), ret,
503 msg = (struct UDPMessage *) buf;
506 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
507 ("header reports message size of %d\n"),
508 ntohs (msg->header.size));
510 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
511 ("header reports message type of %d\n"),
512 ntohs (msg->header.type));
514 if (ntohs (msg->header.size) < sizeof (struct UDPMessage))
517 GNUNET_NETWORK_fdset_zero (plugin->rs);
518 GNUNET_NETWORK_fdset_set (plugin->rs, udp_sock);
521 msgbuf = (char *)&msg[1];
522 sender = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
523 memcpy (sender, &msg->sender, sizeof (struct GNUNET_PeerIdentity));
527 tsize = ntohs (msg->header.size) - sizeof(struct UDPMessage);
529 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "UDP", _
530 ("offset is %d, tsize is %d (UDPMessage size is %d)\n"),
531 offset, tsize, sizeof(struct UDPMessage));
534 if (fromlen == sizeof (struct sockaddr_in))
536 s4 = (const struct sockaddr_in*) &addr;
537 t4.u_port = s4->sin_port;
538 t4.ipv4_addr = s4->sin_addr.s_addr;
540 calen = sizeof (struct IPv4UdpAddress);
542 else if (fromlen == sizeof (struct sockaddr_in6))
544 s6 = (const struct sockaddr_in6*) &addr;
545 t6.u6_port = s6->sin6_port;
546 memcpy (t6.ipv6_addr,
547 s6->sin6_addr.s6_addr,
550 calen = sizeof (struct IPv6UdpAddress);
558 while (offset < tsize)
560 currhdr = (struct GNUNET_MessageHeader *)&msgbuf[offset];
562 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
563 ("processing msg %d: type %d, size %d at offset %d\n"),
564 count, ntohs(currhdr->type), ntohs(currhdr->size), offset);
566 plugin->env->receive (plugin->env->cls,
567 sender, currhdr, UDP_DIRECT_DISTANCE,
569 offset += ntohs(currhdr->size);
571 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "udp", _
572 ("offset now %d, tsize %d\n"),
578 GNUNET_free (sender);
581 plugin->select_task =
582 GNUNET_SCHEDULER_add_select (plugin->env->sched,
583 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
584 GNUNET_SCHEDULER_NO_TASK,
585 GNUNET_TIME_UNIT_FOREVER_REL, plugin->rs,
586 NULL, &udp_plugin_select, plugin);
591 * Create a UDP socket. If possible, use IPv6, otherwise
593 * @param cls closure, the 'struct Plugin*'
595 static struct GNUNET_NETWORK_Handle *
596 udp_transport_server_start (void *cls)
598 struct Plugin *plugin = cls;
599 struct GNUNET_NETWORK_Handle *desc;
600 struct sockaddr_in serverAddrv4;
601 struct sockaddr_in6 serverAddrv6;
602 struct sockaddr *serverAddr;
607 GNUNET_CONFIGURATION_get_value_yesno (plugin->env->cfg, "GNUNETD",
610 desc = GNUNET_NETWORK_socket_create (PF_INET6, SOCK_DGRAM, 17);
613 memset (&serverAddrv6, 0, sizeof (serverAddrv6));
614 #if HAVE_SOCKADDR_IN_SIN_LEN
615 serverAddrv6.sin6_len = sizeof (serverAddrv6);
617 serverAddrv6.sin6_family = AF_INET6;
618 serverAddrv6.sin6_addr = in6addr_any;
619 serverAddrv6.sin6_port = htons (plugin->open_port);
620 addrlen = sizeof (serverAddrv6);
621 serverAddr = (struct sockaddr *) &serverAddrv6;
626 desc = GNUNET_NETWORK_socket_create (PF_INET, SOCK_DGRAM, 17);
629 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "udp", "socket");
634 memset (&serverAddrv4, 0, sizeof (serverAddrv4));
635 #if HAVE_SOCKADDR_IN_SIN_LEN
636 serverAddrv4.sin_len = sizeof (serverAddrv4);
638 serverAddrv4.sin_family = AF_INET;
639 serverAddrv4.sin_addr.s_addr = INADDR_ANY;
640 serverAddrv4.sin_port = htons (plugin->open_port);
641 addrlen = sizeof (serverAddrv4);
642 serverAddr = (struct sockaddr *) &serverAddrv4;
648 GNUNET_assert (GNUNET_NETWORK_socket_bind (desc, serverAddr, addrlen) ==
652 plugin->rs = GNUNET_NETWORK_fdset_create ();
654 GNUNET_NETWORK_fdset_zero (plugin->rs);
655 GNUNET_NETWORK_fdset_set (plugin->rs, desc);
657 plugin->select_task =
658 GNUNET_SCHEDULER_add_select (plugin->env->sched,
659 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
660 GNUNET_SCHEDULER_NO_TASK,
661 GNUNET_TIME_UNIT_FOREVER_REL, plugin->rs,
662 NULL, &udp_plugin_select, plugin);
669 * Check if the given port is plausible (must be either
670 * our listen port or our advertised port). If it is
671 * neither, we return one of these two ports at random.
673 * @return either in_port or a more plausible port
676 check_port (struct Plugin *plugin, uint16_t in_port)
678 if ((in_port == plugin->adv_port) || (in_port == plugin->open_port))
680 return (GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
682 ? plugin->open_port : plugin->adv_port;
687 * Another peer has suggested an address for this peer and transport
688 * plugin. Check that this could be a valid address. This function
689 * is not expected to 'validate' the address in the sense of trying to
690 * connect to it but simply to see if the binary format is technically
691 * legal for establishing a connection.
693 * @param cls handle to Plugin
694 * @param addr address to check
695 * @param addrlen length of addr
696 * @return GNUNET_OK if this is a plausible address for this peer
697 * and transport, GNUNET_SYSERR if not
700 udp_check_address (void *cls, void *addr, size_t addrlen)
702 struct Plugin *plugin = cls;
703 struct IPv4UdpAddress *v4;
704 struct IPv6UdpAddress *v6;
706 if ((addrlen != sizeof (struct IPv4UdpAddress)) &&
707 (addrlen != sizeof (struct IPv6UdpAddress)))
710 return GNUNET_SYSERR;
712 if (addrlen == sizeof (struct IPv4UdpAddress))
714 v4 = (struct IPv4UdpAddress *) addr;
715 v4->u_port = htons (check_port (plugin, ntohs (v4->u_port)));
719 v6 = (struct IPv6UdpAddress *) addr;
720 v6->u6_port = htons (check_port (plugin, ntohs (v6->u6_port)));
727 * Append our port and forward the result.
730 append_port (void *cls, const char *hostname)
732 struct PrettyPrinterContext *ppc = cls;
735 if (hostname == NULL)
737 ppc->asc (ppc->asc_cls, NULL);
741 GNUNET_asprintf (&ret, "%s:%d", hostname, ppc->port);
742 ppc->asc (ppc->asc_cls, ret);
748 * Convert the transports address to a nice, human-readable
752 * @param type name of the transport that generated the address
753 * @param addr one of the addresses of the host, NULL for the last address
754 * the specific address format depends on the transport
755 * @param addrlen length of the address
756 * @param numeric should (IP) addresses be displayed in numeric form?
757 * @param timeout after how long should we give up?
758 * @param asc function to call on each string
759 * @param asc_cls closure for asc
762 udp_plugin_address_pretty_printer (void *cls,
767 struct GNUNET_TIME_Relative timeout,
768 GNUNET_TRANSPORT_AddressStringCallback asc,
771 struct Plugin *plugin = cls;
772 struct PrettyPrinterContext *ppc;
774 struct sockaddr_in a4;
775 struct sockaddr_in6 a6;
776 const struct IPv4UdpAddress *t4;
777 const struct IPv6UdpAddress *t6;
782 if (addrlen == sizeof (struct IPv6UdpAddress))
786 memset (&a6, 0, sizeof (a6));
787 a6.sin6_family = AF_INET6;
788 a6.sin6_port = t6->u6_port;
789 port = ntohs (t6->u6_port);
790 memcpy (a6.sin6_addr.s6_addr,
796 else if (addrlen == sizeof (struct IPv4UdpAddress))
800 memset (&a4, 0, sizeof (a4));
801 a4.sin_family = AF_INET;
802 a4.sin_port = t4->u_port;
803 a4.sin_addr.s_addr = t4->ipv4_addr;
804 port = ntohs (t4->u_port);
810 /* invalid address */
815 ppc = GNUNET_malloc (sizeof (struct PrettyPrinterContext));
817 ppc->asc_cls = asc_cls;
819 GNUNET_RESOLVER_hostname_get (plugin->env->sched,
823 !numeric, timeout, &append_port, ppc);
829 * Function called for a quick conversion of the binary address to
830 * a numeric address. Note that the caller must not free the
831 * address and that the next call to this function is allowed
832 * to override the address again.
835 * @param addr binary address
836 * @param addrlen length of the address
837 * @return string representing the same address
840 udp_address_to_string (void *cls,
844 static char rbuf[INET6_ADDRSTRLEN + 10];
845 char buf[INET6_ADDRSTRLEN];
849 const struct IPv4UdpAddress *t4;
850 const struct IPv6UdpAddress *t6;
854 if (addrlen == sizeof (struct IPv6UdpAddress))
858 port = ntohs (t6->u6_port);
859 memcpy (&a6, t6->ipv6_addr, sizeof (a6));
862 else if (addrlen == sizeof (struct IPv4UdpAddress))
866 port = ntohs (t4->u_port);
867 memcpy (&a4, &t4->ipv4_addr, sizeof (a4));
872 inet_ntop (af, sb, buf, INET6_ADDRSTRLEN);
873 GNUNET_snprintf (rbuf,
883 * The exported method. Makes the core api available via a global and
884 * returns the udp transport API.
886 * @param cls closure, the 'struct GNUNET_TRANSPORT_PluginEnvironment*'
887 * @return the 'struct GNUNET_TRANSPORT_PluginFunctions*' or NULL on error
890 libgnunet_plugin_transport_udp_init (void *cls)
892 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
893 struct GNUNET_TRANSPORT_PluginFunctions *api;
894 struct Plugin *plugin;
895 struct GNUNET_SERVICE_Context *service;
896 unsigned long long aport;
897 unsigned long long bport;
898 unsigned long long mtu;
900 service = GNUNET_SERVICE_start ("transport-udp", env->sched, env->cfg);
903 GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING, "udp", _
904 ("Failed to start service for `%s' transport plugin.\n"),
910 GNUNET_CONFIGURATION_get_value_number (env->cfg,
916 GNUNET_CONFIGURATION_get_value_number (env->cfg,
919 &aport)) && (aport > 65535)))
921 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
924 ("Require valid port number for service `%s' in configuration!\n"),
926 GNUNET_SERVICE_stop (service);
934 GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
936 _("MTU %llu for `%s' is probably too low!\n"), mtu,
939 plugin = GNUNET_malloc (sizeof (struct Plugin));
940 plugin->open_port = bport;
941 plugin->adv_port = aport;
943 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
946 api->send = &udp_plugin_send;
947 api->disconnect = &udp_disconnect;
948 api->address_pretty_printer = &udp_plugin_address_pretty_printer;
949 api->check_address = &udp_check_address;
950 api->address_to_string = &udp_address_to_string;
951 plugin->service = service;
953 /* FIXME: do the two calls below periodically again and
954 not just once (since the info we get might change...) */
955 GNUNET_OS_network_interfaces_list (&process_interfaces, plugin);
956 plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (env->sched,
959 HOSTNAME_RESOLVE_TIMEOUT,
960 &process_hostname_ips,
963 udp_sock = udp_transport_server_start (plugin);
965 GNUNET_assert (udp_sock != NULL);
971 libgnunet_plugin_transport_udp_done (void *cls)
973 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
974 struct Plugin *plugin = api->cls;
976 udp_transport_server_stop (plugin);
977 if (NULL != plugin->hostname_dns)
979 GNUNET_RESOLVER_request_cancel (plugin->hostname_dns);
980 plugin->hostname_dns = NULL;
982 GNUNET_SERVICE_stop (plugin->service);
984 GNUNET_NETWORK_fdset_destroy (plugin->rs);
985 GNUNET_free (plugin);
990 /* end of plugin_transport_udp.c */