2 This file is part of GNUnet
3 Copyright (C) 2010, 2011 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
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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_broadcasting.c
23 * @brief Neighbour discovery with UDP
24 * @author Christian Grothoff
25 * @author Matthias Wachs
28 #include "plugin_transport_udp.h"
29 #include "gnunet_hello_lib.h"
30 #include "gnunet_util_lib.h"
31 #include "gnunet_fragmentation_lib.h"
32 #include "gnunet_nat_lib.h"
33 #include "gnunet_protocols.h"
34 #include "gnunet_resolver_service.h"
35 #include "gnunet_signatures.h"
36 #include "gnunet_constants.h"
37 #include "gnunet_statistics_service.h"
38 #include "gnunet_transport_service.h"
39 #include "gnunet_transport_plugin.h"
40 #include "transport.h"
42 #define LOG(kind,...) GNUNET_log_from (kind, "transport-udp", __VA_ARGS__)
44 /* *********** Cryogenic ********** */
49 #include <sys/ioctl.h>
50 #include <sys/select.h>
54 #define PM_SET_DELAY_AND_TIMEOUT _IOW(PM_MAGIC, 1, struct pm_times)
57 unsigned long delay_msecs;
58 unsigned long timeout_msecs;
61 /************************************/
64 struct UDP_Beacon_Message
69 struct GNUNET_MessageHeader header;
72 * What is the identity of the sender
74 struct GNUNET_PeerIdentity sender;
78 struct BroadcastAddress
80 struct BroadcastAddress *next;
82 struct BroadcastAddress *prev;
85 * ID of select broadcast task
87 struct GNUNET_SCHEDULER_Task * broadcast_task;
89 struct Plugin *plugin;
91 struct sockaddr *addr;
99 struct GNUNET_DISK_FileHandle *cryogenic_fd;
102 * Time out for cryogenic.
104 struct pm_times cryogenic_times;
110 * Client-specific context for #broadcast_mst_cb().
114 struct Plugin *plugin;
116 const union UdpAddress *udp_addr;
123 enum GNUNET_ATS_Network_Type ats_address_network_type;
128 * Parse broadcast message received.
130 * @param cls the `struct Plugin`
131 * @param client the `struct MstContext` with sender address
132 * @param message the message we received
133 * @return #GNUNET_OK (always)
136 broadcast_mst_cb (void *cls,
138 const struct GNUNET_MessageHeader *message)
140 struct Plugin *plugin = cls;
141 struct MstContext *mc = client;
142 struct GNUNET_HELLO_Address *address;
143 const struct GNUNET_MessageHeader *hello;
144 const struct UDP_Beacon_Message *msg;
146 msg = (const struct UDP_Beacon_Message *) message;
148 if (GNUNET_MESSAGE_TYPE_TRANSPORT_BROADCAST_BEACON !=
149 ntohs (msg->header.type))
151 LOG (GNUNET_ERROR_TYPE_DEBUG,
152 "Received beacon with %u bytes from peer `%s' via address `%s'\n",
153 ntohs (msg->header.size),
154 GNUNET_i2s (&msg->sender),
155 udp_address_to_string (NULL,
158 hello = (struct GNUNET_MessageHeader *) &msg[1];
159 address = GNUNET_HELLO_address_allocate (&msg->sender,
163 GNUNET_HELLO_ADDRESS_INFO_NONE);
164 plugin->env->receive (plugin->env->cls,
168 GNUNET_HELLO_address_free (address);
169 GNUNET_STATISTICS_update (plugin->env->stats,
170 _("# Multicast HELLO beacons received via UDP"),
177 * We received a broadcast message. Process it and all subsequent
178 * messages in the same packet.
180 * @param plugin the UDP plugin
181 * @param buf the buffer with the message(s)
182 * @param size number of bytes in @a buf
183 * @param udp_addr address of the sender
184 * @param udp_addr_len number of bytes in @a udp_addr
185 * @param network_type network type of the sender's address
188 udp_broadcast_receive (struct Plugin *plugin,
191 const union UdpAddress *udp_addr,
193 enum GNUNET_ATS_Network_Type network_type)
195 struct MstContext mc;
197 mc.udp_addr = udp_addr;
198 mc.udp_addr_len = udp_addr_len;
199 mc.ats_address_network_type = network_type;
200 GNUNET_SERVER_mst_receive (plugin->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 memcpy (&msg[1], hello, hello_size);
235 udp_ipv4_broadcast_send (void *cls,
236 const struct GNUNET_SCHEDULER_TaskContext *tc)
238 struct BroadcastAddress *baddr = cls;
239 struct Plugin *plugin = baddr->plugin;
242 char buf[65536] GNUNET_ALIGN;
244 baddr->broadcast_task = NULL;
246 msg_size = prepare_beacon(plugin, (struct UDP_Beacon_Message *) &buf);
249 struct sockaddr_in *addr = (struct sockaddr_in *) baddr->addr;
251 addr->sin_port = htons (plugin->port);
252 sent = GNUNET_NETWORK_socket_sendto (plugin->sockv4, &buf, msg_size,
253 (const struct sockaddr *) addr,
255 if (sent == GNUNET_SYSERR)
257 if ((ENETUNREACH == errno) || (ENETDOWN == errno))
259 /* "Network unreachable" or "Network down"
261 * This indicates that we just do not have network connectivity
263 GNUNET_log (GNUNET_ERROR_TYPE_BULK | GNUNET_ERROR_TYPE_WARNING,
264 "Network connectivity is down, cannot send beacon!\n");
267 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "sendto");
271 LOG (GNUNET_ERROR_TYPE_DEBUG,
272 "Sent HELLO beacon broadcast with %i bytes to address %s\n", sent,
273 GNUNET_a2s (baddr->addr, baddr->addrlen));
281 if (NULL != baddr->cryogenic_fd)
283 baddr->cryogenic_times.delay_msecs = (plugin->broadcast_interval.rel_value_us/1000.0)*0.5;
284 baddr->cryogenic_times.timeout_msecs = (plugin->broadcast_interval.rel_value_us/1000.0)*1.5;
286 if (ioctl(baddr->cryogenic_fd->fd,
287 PM_SET_DELAY_AND_TIMEOUT,
288 &baddr->cryogenic_times) < 0)
290 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "ioctl");
291 baddr->broadcast_task =
292 GNUNET_SCHEDULER_add_delayed (plugin->broadcast_interval,
293 &udp_ipv4_broadcast_send, baddr);
296 GNUNET_SCHEDULER_add_write_file (GNUNET_TIME_UNIT_FOREVER_REL,
298 &udp_ipv4_broadcast_send,
304 baddr->broadcast_task =
305 GNUNET_SCHEDULER_add_delayed (plugin->broadcast_interval,
306 &udp_ipv4_broadcast_send, baddr);
311 udp_ipv6_broadcast_send (void *cls,
312 const struct GNUNET_SCHEDULER_TaskContext *tc)
314 struct BroadcastAddress *baddr = cls;
315 struct Plugin *plugin = baddr->plugin;
318 char buf[65536] GNUNET_ALIGN;
319 const struct sockaddr_in6 *s6 = (const struct sockaddr_in6 *) baddr->addr;
321 baddr->broadcast_task = NULL;
323 msg_size = prepare_beacon(plugin, (struct UDP_Beacon_Message *) &buf);
324 /* Note: unclear if this actually works to limit the multicast to
325 the specified interface as we're not (necessarily) using a
326 link-local multicast group and the kernel suggests that the
327 scope ID is only respected for link-local addresses; however,
328 if the scope ID is ignored, the kernel should just multicast
329 on ALL interfaces, which is merely slightly less efficient;
330 in that case, we might want to revert to only doing this
331 once, and not per interface (hard to test...) */
332 plugin->ipv6_multicast_address.sin6_scope_id = s6->sin6_scope_id;
333 sent = GNUNET_NETWORK_socket_sendto (plugin->sockv6, &buf, msg_size,
334 (const struct sockaddr *)
335 &plugin->ipv6_multicast_address,
336 sizeof (struct sockaddr_in6));
337 plugin->ipv6_multicast_address.sin6_scope_id = 0;
338 if (sent == GNUNET_SYSERR)
340 if ((ENETUNREACH == errno) || (ENETDOWN == errno))
342 /* "Network unreachable" or "Network down"
344 * This indicates that this system is IPv6 enabled, but does not
345 * have a valid global IPv6 address assigned
347 GNUNET_log (GNUNET_ERROR_TYPE_BULK | GNUNET_ERROR_TYPE_WARNING,
348 "Network connectivity is down, cannot send beacon!\n");
351 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "sendto");
355 LOG (GNUNET_ERROR_TYPE_DEBUG,
356 "Sending IPv6 HELLO beacon broadcast with %d bytes to address %s\n",
358 GNUNET_a2s ((const struct sockaddr *) &plugin->ipv6_multicast_address,
359 sizeof (struct sockaddr_in6)));
365 if (NULL != baddr->cryogenic_fd)
367 baddr->cryogenic_times.delay_msecs = (plugin->broadcast_interval.rel_value_us/1000.0)*0.5;
368 baddr->cryogenic_times.timeout_msecs = (plugin->broadcast_interval.rel_value_us/1000.0)*1.5;
370 if (ioctl(baddr->cryogenic_fd->fd,
371 PM_SET_DELAY_AND_TIMEOUT,
372 &baddr->cryogenic_times) < 0)
374 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "ioctl");
375 baddr->broadcast_task =
376 GNUNET_SCHEDULER_add_delayed (plugin->broadcast_interval,
377 &udp_ipv6_broadcast_send, baddr);
380 GNUNET_SCHEDULER_add_write_file (GNUNET_TIME_UNIT_FOREVER_REL,
382 &udp_ipv4_broadcast_send,
387 baddr->broadcast_task =
388 GNUNET_SCHEDULER_add_delayed (plugin->broadcast_interval,
389 &udp_ipv6_broadcast_send, baddr);
394 * Callback function invoked for each interface found.
396 * @param cls closure with the `struct Plugin`
397 * @param name name of the interface (can be NULL for unknown)
398 * @param isDefault is this presumably the default interface
399 * @param addr address of this interface (can be NULL for unknown or unassigned)
400 * @param broadcast_addr the broadcast address (can be NULL for unknown or unassigned)
401 * @param netmask the network mask (can be NULL for unknown or unassigned)
402 * @param addrlen length of the address
403 * @return #GNUNET_OK to continue iteration, #GNUNET_SYSERR to abort
406 iface_proc (void *cls,
409 const struct sockaddr *addr,
410 const struct sockaddr *broadcast_addr,
411 const struct sockaddr *netmask, socklen_t addrlen)
413 struct Plugin *plugin = cls;
414 struct BroadcastAddress *ba;
415 enum GNUNET_ATS_Network_Type network;
419 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
420 "address %s for interface %s %p\n ",
421 GNUNET_a2s (addr, addrlen), name, addr);
422 if (NULL == broadcast_addr)
424 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
425 "broadcast address %s for interface %s %p\n ",
426 GNUNET_a2s (broadcast_addr, addrlen), name, broadcast_addr);
427 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "netmask %s for interface %s %p\n ",
428 GNUNET_a2s (netmask, addrlen), name, netmask);
430 network = plugin->env->get_address_type (plugin->env->cls, broadcast_addr, addrlen);
431 if (GNUNET_ATS_NET_LOOPBACK == network)
433 /* Broadcasting on loopback does not make sense */
437 ba = GNUNET_new (struct BroadcastAddress);
439 ba->addr = GNUNET_malloc (addrlen);
440 memcpy (ba->addr, broadcast_addr, addrlen);
441 ba->addrlen = addrlen;
443 if ( (GNUNET_YES == plugin->enable_ipv4) &&
444 (NULL != plugin->sockv4) &&
445 (addrlen == sizeof (struct sockaddr_in)) )
449 * setup Cryogenic FD for ipv4 broadcasting
453 GNUNET_asprintf (&filename,
456 if (0 == ACCESS (name, R_OK))
459 GNUNET_DISK_file_open (filename,
460 GNUNET_DISK_OPEN_WRITE,
461 GNUNET_DISK_PERM_NONE);
463 GNUNET_free (filename);
466 GNUNET_SCHEDULER_add_now (&udp_ipv4_broadcast_send, ba);
468 if ((GNUNET_YES == plugin->enable_ipv6) &&
469 (NULL != plugin->sockv6) &&
470 (addrlen == sizeof (struct sockaddr_in6)))
472 /* Create IPv6 multicast request */
473 struct ipv6_mreq multicastRequest;
474 const struct sockaddr_in6 *s6 = (const struct sockaddr_in6 *) broadcast_addr;
476 multicastRequest.ipv6mr_multiaddr =
477 plugin->ipv6_multicast_address.sin6_addr;
478 /* http://tools.ietf.org/html/rfc2553#section-5.2:
482 * Join a multicast group on a specified local interface. If the
483 * interface index is specified as 0, the kernel chooses the local
484 * interface. For example, some kernels look up the multicast
485 * group in the normal IPv6 routing table and using the resulting
486 * interface; we do this for each interface, so no need to use
489 multicastRequest.ipv6mr_interface = s6->sin6_scope_id;
491 /* Join the multicast group */
493 GNUNET_NETWORK_socket_setsockopt
494 (plugin->sockv6, IPPROTO_IPV6, IPV6_JOIN_GROUP,
495 &multicastRequest, sizeof (multicastRequest)))
497 LOG (GNUNET_ERROR_TYPE_WARNING,
498 "Failed to join IPv6 multicast group: IPv6 broadcasting not running\n");
504 * setup Cryogenic FD for ipv6 broadcasting
508 GNUNET_asprintf (&filename,
511 if (0 == ACCESS (name, R_OK))
514 GNUNET_DISK_file_open (filename,
515 GNUNET_DISK_OPEN_WRITE,
516 GNUNET_DISK_PERM_NONE);
518 GNUNET_free (filename);
521 GNUNET_SCHEDULER_add_now (&udp_ipv6_broadcast_send, ba);
524 GNUNET_CONTAINER_DLL_insert (plugin->broadcast_head,
525 plugin->broadcast_tail, ba);
531 setup_broadcast (struct Plugin *plugin,
532 struct sockaddr_in6 *server_addrv6,
533 struct sockaddr_in *server_addrv4)
536 GNUNET_CONFIGURATION_get_value_yesno (plugin->env->cfg,
540 LOG (GNUNET_ERROR_TYPE_WARNING,
541 _("Disabling HELLO broadcasting due to friend-to-friend only configuration!\n"));
545 /* always create tokenizers */
546 plugin->broadcast_mst =
547 GNUNET_SERVER_mst_create (&broadcast_mst_cb, plugin);
549 if (GNUNET_YES != plugin->enable_broadcasting)
550 return; /* We do not send, just receive */
552 /* create IPv4 broadcast socket */
553 if ((GNUNET_YES == plugin->enable_ipv4) && (NULL != plugin->sockv4))
557 if (GNUNET_NETWORK_socket_setsockopt
558 (plugin->sockv4, SOL_SOCKET, SO_BROADCAST, &yes,
559 sizeof (int)) != GNUNET_OK)
561 LOG (GNUNET_ERROR_TYPE_WARNING,
562 _("Failed to set IPv4 broadcast option for broadcast socket on port %d\n"),
563 ntohs (server_addrv4->sin_port));
566 /* create IPv6 multicast socket */
567 if ((GNUNET_YES == plugin->enable_ipv6) && (plugin->sockv6 != NULL))
569 memset (&plugin->ipv6_multicast_address, 0, sizeof (struct sockaddr_in6));
571 inet_pton (AF_INET6, "FF05::13B",
572 &plugin->ipv6_multicast_address.sin6_addr));
573 plugin->ipv6_multicast_address.sin6_family = AF_INET6;
574 plugin->ipv6_multicast_address.sin6_port = htons (plugin->port);
576 GNUNET_OS_network_interfaces_list (&iface_proc, plugin);
581 stop_broadcast (struct Plugin *plugin)
583 if (GNUNET_YES == plugin->enable_broadcasting)
585 /* Disable broadcasting */
586 while (plugin->broadcast_head != NULL)
588 struct BroadcastAddress *p = plugin->broadcast_head;
590 if (p->broadcast_task != NULL)
592 GNUNET_SCHEDULER_cancel (p->broadcast_task);
593 p->broadcast_task = NULL;
595 if ((GNUNET_YES == plugin->enable_ipv6) &&
596 (NULL != plugin->sockv6) &&
597 (p->addrlen == sizeof (struct sockaddr_in6)))
599 /* Create IPv6 multicast request */
600 struct ipv6_mreq multicastRequest;
601 const struct sockaddr_in6 *s6 = (const struct sockaddr_in6 *) p->addr;
603 multicastRequest.ipv6mr_multiaddr =
604 plugin->ipv6_multicast_address.sin6_addr;
605 multicastRequest.ipv6mr_interface = s6->sin6_scope_id;
607 /* Leave the multicast group */
609 GNUNET_NETWORK_socket_setsockopt
610 (plugin->sockv6, IPPROTO_IPV6, IPV6_LEAVE_GROUP,
611 &multicastRequest, sizeof (multicastRequest)))
613 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "setsockopt");
617 LOG (GNUNET_ERROR_TYPE_DEBUG, "IPv6 multicasting stopped\n");
622 GNUNET_DISK_file_close(p->cryogenic_fd);
624 GNUNET_CONTAINER_DLL_remove (plugin->broadcast_head,
625 plugin->broadcast_tail, p);
626 GNUNET_free (p->addr);
632 if (NULL != plugin->broadcast_mst)
634 GNUNET_SERVER_mst_destroy (plugin->broadcast_mst);
635 plugin->broadcast_mst = NULL;
639 /* end of plugin_transport_udp_broadcasting.c */