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13 Affero General Public License for more details.
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16 along with this program. If not, see <http://www.gnu.org/licenses/>.
20 * @file transport/plugin_transport_udp_broadcasting.c
21 * @brief Neighbour discovery with UDP
22 * @author Christian Grothoff
23 * @author Matthias Wachs
26 #include "plugin_transport_udp.h"
27 #include "gnunet_hello_lib.h"
28 #include "gnunet_util_lib.h"
29 #include "gnunet_fragmentation_lib.h"
30 #include "gnunet_protocols.h"
31 #include "gnunet_resolver_service.h"
32 #include "gnunet_signatures.h"
33 #include "gnunet_constants.h"
34 #include "gnunet_statistics_service.h"
35 #include "gnunet_transport_service.h"
36 #include "gnunet_transport_plugin.h"
37 #include "transport.h"
39 #define LOG(kind,...) GNUNET_log_from (kind, "transport-udp", __VA_ARGS__)
41 /* *********** Cryogenic ********** */
46 #include <sys/ioctl.h>
47 #include <sys/select.h>
51 #define PM_SET_DELAY_AND_TIMEOUT _IOW(PM_MAGIC, 1, struct pm_times)
54 unsigned long delay_msecs;
55 unsigned long timeout_msecs;
58 /************************************/
61 struct UDP_Beacon_Message
66 struct GNUNET_MessageHeader header;
69 * What is the identity of the sender
71 struct GNUNET_PeerIdentity sender;
75 struct BroadcastAddress
77 struct BroadcastAddress *next;
79 struct BroadcastAddress *prev;
82 * ID of select broadcast task
84 struct GNUNET_SCHEDULER_Task * broadcast_task;
86 struct Plugin *plugin;
88 struct sockaddr *addr;
96 struct GNUNET_DISK_FileHandle *cryogenic_fd;
99 * Time out for cryogenic.
101 struct pm_times cryogenic_times;
107 * Client-specific context for #broadcast_mst_cb().
111 struct Plugin *plugin;
113 const union UdpAddress *udp_addr;
120 enum GNUNET_ATS_Network_Type ats_address_network_type;
125 * Parse broadcast message received.
127 * @param cls the `struct Plugin`
128 * @param client the `struct MstContext` with sender address
129 * @param message the message we received
130 * @return #GNUNET_OK (always)
133 broadcast_mst_cb (void *cls,
134 const struct GNUNET_MessageHeader *message)
136 struct MstContext *mc = cls;
137 struct Plugin *plugin = mc->plugin;
138 struct GNUNET_HELLO_Address *address;
139 const struct GNUNET_MessageHeader *hello;
140 const struct UDP_Beacon_Message *msg;
142 msg = (const struct UDP_Beacon_Message *) message;
144 if (GNUNET_MESSAGE_TYPE_TRANSPORT_BROADCAST_BEACON !=
145 ntohs (msg->header.type))
147 LOG (GNUNET_ERROR_TYPE_DEBUG,
148 "Received beacon with %u bytes from peer `%s' via address `%s'\n",
149 ntohs (msg->header.size),
150 GNUNET_i2s (&msg->sender),
151 udp_address_to_string (NULL,
154 hello = (struct GNUNET_MessageHeader *) &msg[1];
155 address = GNUNET_HELLO_address_allocate (&msg->sender,
159 GNUNET_HELLO_ADDRESS_INFO_NONE);
160 plugin->env->receive (plugin->env->cls,
164 GNUNET_HELLO_address_free (address);
165 GNUNET_STATISTICS_update (plugin->env->stats,
166 _("# Multicast HELLO beacons received via UDP"),
173 * We received a broadcast message. Process it and all subsequent
174 * messages in the same packet.
176 * @param plugin the UDP plugin
177 * @param buf the buffer with the message(s)
178 * @param size number of bytes in @a buf
179 * @param udp_addr address of the sender
180 * @param udp_addr_len number of bytes in @a udp_addr
181 * @param network_type network type of the sender's address
184 udp_broadcast_receive (struct Plugin *plugin,
187 const union UdpAddress *udp_addr,
189 enum GNUNET_ATS_Network_Type network_type)
191 struct GNUNET_MessageStreamTokenizer *broadcast_mst;
192 struct MstContext mc;
194 broadcast_mst = GNUNET_MST_create (&broadcast_mst_cb,
197 mc.udp_addr = udp_addr;
198 mc.udp_addr_len = udp_addr_len;
199 mc.ats_address_network_type = network_type;
200 GNUNET_MST_from_buffer (broadcast_mst,
204 GNUNET_MST_destroy (broadcast_mst);
209 prepare_beacon (struct Plugin *plugin,
210 struct UDP_Beacon_Message *msg)
215 const struct GNUNET_MessageHeader *hello;
216 hello = plugin->env->get_our_hello ();
219 hello_size = GNUNET_HELLO_size ((struct GNUNET_HELLO_Message *) hello);
220 msg_size = hello_size + sizeof (struct UDP_Beacon_Message);
222 if (hello_size < (sizeof (struct GNUNET_MessageHeader)) ||
223 (msg_size > (UDP_MTU)))
226 msg->sender = *(plugin->env->my_identity);
227 msg->header.size = htons (msg_size);
228 msg->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_BROADCAST_BEACON);
229 GNUNET_memcpy (&msg[1], hello, hello_size);
235 udp_ipv4_broadcast_send (void *cls)
237 struct BroadcastAddress *baddr = cls;
238 struct Plugin *plugin = baddr->plugin;
241 char buf[65536] GNUNET_ALIGN;
243 baddr->broadcast_task = NULL;
245 msg_size = prepare_beacon(plugin, (struct UDP_Beacon_Message *) &buf);
248 struct sockaddr_in *addr = (struct sockaddr_in *) baddr->addr;
250 addr->sin_port = htons (plugin->port);
251 sent = GNUNET_NETWORK_socket_sendto (plugin->sockv4, &buf, msg_size,
252 (const struct sockaddr *) addr,
254 if (sent == GNUNET_SYSERR)
256 if ((ENETUNREACH == errno) || (ENETDOWN == errno))
258 /* "Network unreachable" or "Network down"
260 * This indicates that we just do not have network connectivity
262 GNUNET_log (GNUNET_ERROR_TYPE_BULK | GNUNET_ERROR_TYPE_WARNING,
263 "Network connectivity is down, cannot send beacon!\n");
266 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "sendto");
270 LOG (GNUNET_ERROR_TYPE_DEBUG,
271 "Sent HELLO beacon broadcast with %i bytes to address %s\n", sent,
272 GNUNET_a2s (baddr->addr, baddr->addrlen));
280 if (NULL != baddr->cryogenic_fd)
282 baddr->cryogenic_times.delay_msecs = (plugin->broadcast_interval.rel_value_us/1000.0)*0.5;
283 baddr->cryogenic_times.timeout_msecs = (plugin->broadcast_interval.rel_value_us/1000.0)*1.5;
285 if (ioctl(baddr->cryogenic_fd->fd,
286 PM_SET_DELAY_AND_TIMEOUT,
287 &baddr->cryogenic_times) < 0)
289 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "ioctl");
290 baddr->broadcast_task =
291 GNUNET_SCHEDULER_add_delayed (plugin->broadcast_interval,
292 &udp_ipv4_broadcast_send, baddr);
295 GNUNET_SCHEDULER_add_write_file (GNUNET_TIME_UNIT_FOREVER_REL,
297 &udp_ipv4_broadcast_send,
303 baddr->broadcast_task =
304 GNUNET_SCHEDULER_add_delayed (plugin->broadcast_interval,
305 &udp_ipv4_broadcast_send, baddr);
310 udp_ipv6_broadcast_send (void *cls)
312 struct BroadcastAddress *baddr = cls;
313 struct Plugin *plugin = baddr->plugin;
316 char buf[65536] GNUNET_ALIGN;
317 const struct sockaddr_in6 *s6 = (const struct sockaddr_in6 *) baddr->addr;
319 baddr->broadcast_task = NULL;
321 msg_size = prepare_beacon(plugin, (struct UDP_Beacon_Message *) &buf);
322 /* Note: unclear if this actually works to limit the multicast to
323 the specified interface as we're not (necessarily) using a
324 link-local multicast group and the kernel suggests that the
325 scope ID is only respected for link-local addresses; however,
326 if the scope ID is ignored, the kernel should just multicast
327 on ALL interfaces, which is merely slightly less efficient;
328 in that case, we might want to revert to only doing this
329 once, and not per interface (hard to test...) */
330 plugin->ipv6_multicast_address.sin6_scope_id = s6->sin6_scope_id;
331 sent = GNUNET_NETWORK_socket_sendto (plugin->sockv6, &buf, msg_size,
332 (const struct sockaddr *)
333 &plugin->ipv6_multicast_address,
334 sizeof (struct sockaddr_in6));
335 plugin->ipv6_multicast_address.sin6_scope_id = 0;
336 if (sent == GNUNET_SYSERR)
338 if ((ENETUNREACH == errno) || (ENETDOWN == errno))
340 /* "Network unreachable" or "Network down"
342 * This indicates that this system is IPv6 enabled, but does not
343 * have a valid global IPv6 address assigned
345 GNUNET_log (GNUNET_ERROR_TYPE_BULK | GNUNET_ERROR_TYPE_WARNING,
346 "Network connectivity is down, cannot send beacon!\n");
349 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "sendto");
353 LOG (GNUNET_ERROR_TYPE_DEBUG,
354 "Sending IPv6 HELLO beacon broadcast with %d bytes to address %s\n",
356 GNUNET_a2s ((const struct sockaddr *) &plugin->ipv6_multicast_address,
357 sizeof (struct sockaddr_in6)));
363 if (NULL != baddr->cryogenic_fd)
365 baddr->cryogenic_times.delay_msecs = (plugin->broadcast_interval.rel_value_us/1000.0)*0.5;
366 baddr->cryogenic_times.timeout_msecs = (plugin->broadcast_interval.rel_value_us/1000.0)*1.5;
368 if (ioctl(baddr->cryogenic_fd->fd,
369 PM_SET_DELAY_AND_TIMEOUT,
370 &baddr->cryogenic_times) < 0)
372 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "ioctl");
373 baddr->broadcast_task =
374 GNUNET_SCHEDULER_add_delayed (plugin->broadcast_interval,
375 &udp_ipv6_broadcast_send, baddr);
378 GNUNET_SCHEDULER_add_write_file (GNUNET_TIME_UNIT_FOREVER_REL,
380 &udp_ipv6_broadcast_send,
385 baddr->broadcast_task =
386 GNUNET_SCHEDULER_add_delayed (plugin->broadcast_interval,
387 &udp_ipv6_broadcast_send, baddr);
392 * Callback function invoked for each interface found.
394 * @param cls closure with the `struct Plugin`
395 * @param name name of the interface (can be NULL for unknown)
396 * @param isDefault is this presumably the default interface
397 * @param addr address of this interface (can be NULL for unknown or unassigned)
398 * @param broadcast_addr the broadcast address (can be NULL for unknown or unassigned)
399 * @param netmask the network mask (can be NULL for unknown or unassigned)
400 * @param addrlen length of the address
401 * @return #GNUNET_OK to continue iteration, #GNUNET_SYSERR to abort
404 iface_proc (void *cls,
407 const struct sockaddr *addr,
408 const struct sockaddr *broadcast_addr,
409 const struct sockaddr *netmask, socklen_t addrlen)
411 struct Plugin *plugin = cls;
412 struct BroadcastAddress *ba;
413 enum GNUNET_ATS_Network_Type network;
417 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
418 "address %s for interface %s %p\n ",
419 GNUNET_a2s (addr, addrlen), name, addr);
420 if (NULL == broadcast_addr)
422 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
423 "broadcast address %s for interface %s %p\n ",
424 GNUNET_a2s (broadcast_addr, addrlen), name, broadcast_addr);
425 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "netmask %s for interface %s %p\n ",
426 GNUNET_a2s (netmask, addrlen), name, netmask);
428 network = plugin->env->get_address_type (plugin->env->cls, broadcast_addr, addrlen);
429 if (GNUNET_ATS_NET_LOOPBACK == network)
431 /* Broadcasting on loopback does not make sense */
435 ba = GNUNET_new (struct BroadcastAddress);
437 ba->addr = GNUNET_malloc (addrlen);
438 GNUNET_memcpy (ba->addr, broadcast_addr, addrlen);
439 ba->addrlen = addrlen;
441 if ( (GNUNET_YES == plugin->enable_ipv4) &&
442 (NULL != plugin->sockv4) &&
443 (addrlen == sizeof (struct sockaddr_in)) )
447 * setup Cryogenic FD for ipv4 broadcasting
451 GNUNET_asprintf (&filename,
454 if (0 == ACCESS (name, R_OK))
457 GNUNET_DISK_file_open (filename,
458 GNUNET_DISK_OPEN_WRITE,
459 GNUNET_DISK_PERM_NONE);
461 GNUNET_free (filename);
464 GNUNET_SCHEDULER_add_now (&udp_ipv4_broadcast_send, ba);
466 if ((GNUNET_YES == plugin->enable_ipv6) &&
467 (NULL != plugin->sockv6) &&
468 (addrlen == sizeof (struct sockaddr_in6)))
470 /* Create IPv6 multicast request */
471 struct ipv6_mreq multicastRequest;
472 const struct sockaddr_in6 *s6 = (const struct sockaddr_in6 *) broadcast_addr;
474 multicastRequest.ipv6mr_multiaddr =
475 plugin->ipv6_multicast_address.sin6_addr;
476 /* http://tools.ietf.org/html/rfc2553#section-5.2:
480 * Join a multicast group on a specified local interface. If the
481 * interface index is specified as 0, the kernel chooses the local
482 * interface. For example, some kernels look up the multicast
483 * group in the normal IPv6 routing table and using the resulting
484 * interface; we do this for each interface, so no need to use
487 multicastRequest.ipv6mr_interface = s6->sin6_scope_id;
489 /* Join the multicast group */
491 GNUNET_NETWORK_socket_setsockopt
492 (plugin->sockv6, IPPROTO_IPV6, IPV6_JOIN_GROUP,
493 &multicastRequest, sizeof (multicastRequest)))
495 LOG (GNUNET_ERROR_TYPE_WARNING,
496 "Failed to join IPv6 multicast group: IPv6 broadcasting not running\n");
502 * setup Cryogenic FD for ipv6 broadcasting
506 GNUNET_asprintf (&filename,
509 if (0 == ACCESS (name, R_OK))
512 GNUNET_DISK_file_open (filename,
513 GNUNET_DISK_OPEN_WRITE,
514 GNUNET_DISK_PERM_NONE);
516 GNUNET_free (filename);
519 GNUNET_SCHEDULER_add_now (&udp_ipv6_broadcast_send, ba);
522 GNUNET_CONTAINER_DLL_insert (plugin->broadcast_head,
523 plugin->broadcast_tail, ba);
529 * Setup broadcasting subsystem.
532 * @param server_addrv6
533 * @param server_addrv4
536 setup_broadcast (struct Plugin *plugin,
537 struct sockaddr_in6 *server_addrv6,
538 struct sockaddr_in *server_addrv4)
541 GNUNET_CONFIGURATION_get_value_yesno (plugin->env->cfg,
545 LOG (GNUNET_ERROR_TYPE_WARNING,
546 _("Disabling HELLO broadcasting due to friend-to-friend only configuration!\n"));
550 if (GNUNET_YES != plugin->enable_broadcasting)
551 return; /* We do not send, just receive */
553 /* create IPv4 broadcast socket */
554 if ((GNUNET_YES == plugin->enable_ipv4) && (NULL != plugin->sockv4))
558 if (GNUNET_NETWORK_socket_setsockopt
559 (plugin->sockv4, SOL_SOCKET, SO_BROADCAST, &yes,
560 sizeof (int)) != GNUNET_OK)
562 LOG (GNUNET_ERROR_TYPE_WARNING,
563 _("Failed to set IPv4 broadcast option for broadcast socket on port %d\n"),
564 ntohs (server_addrv4->sin_port));
567 /* create IPv6 multicast socket */
568 if ((GNUNET_YES == plugin->enable_ipv6) && (plugin->sockv6 != NULL))
570 memset (&plugin->ipv6_multicast_address, 0, sizeof (struct sockaddr_in6));
572 inet_pton (AF_INET6, "FF05::13B",
573 &plugin->ipv6_multicast_address.sin6_addr));
574 plugin->ipv6_multicast_address.sin6_family = AF_INET6;
575 plugin->ipv6_multicast_address.sin6_port = htons (plugin->port);
577 GNUNET_OS_network_interfaces_list (&iface_proc, plugin);
582 * Stop broadcasting subsystem.
587 stop_broadcast (struct Plugin *plugin)
589 if (GNUNET_YES == plugin->enable_broadcasting)
591 /* Disable broadcasting */
592 while (plugin->broadcast_head != NULL)
594 struct BroadcastAddress *p = plugin->broadcast_head;
596 if (p->broadcast_task != NULL)
598 GNUNET_SCHEDULER_cancel (p->broadcast_task);
599 p->broadcast_task = NULL;
601 if ((GNUNET_YES == plugin->enable_ipv6) &&
602 (NULL != plugin->sockv6) &&
603 (p->addrlen == sizeof (struct sockaddr_in6)))
605 /* Create IPv6 multicast request */
606 struct ipv6_mreq multicastRequest;
607 const struct sockaddr_in6 *s6 = (const struct sockaddr_in6 *) p->addr;
609 multicastRequest.ipv6mr_multiaddr =
610 plugin->ipv6_multicast_address.sin6_addr;
611 multicastRequest.ipv6mr_interface = s6->sin6_scope_id;
613 /* Leave the multicast group */
615 GNUNET_NETWORK_socket_setsockopt
616 (plugin->sockv6, IPPROTO_IPV6, IPV6_LEAVE_GROUP,
617 &multicastRequest, sizeof (multicastRequest)))
619 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "setsockopt");
623 LOG (GNUNET_ERROR_TYPE_DEBUG, "IPv6 multicasting stopped\n");
628 GNUNET_DISK_file_close(p->cryogenic_fd);
630 GNUNET_CONTAINER_DLL_remove (plugin->broadcast_head,
631 plugin->broadcast_tail, p);
632 GNUNET_free (p->addr);
638 /* end of plugin_transport_udp_broadcasting.c */