2 This file is part of GNUnet.
3 (C) 2008, 2009, 2010 Christian Grothoff (and other contributing authors)
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13 General Public License for more details.
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22 * @file hostlist/hostlist-server.c
23 * @author Christian Grothoff
24 * @brief application to provide an integrated hostlist HTTP server
28 #include <microhttpd.h>
29 #include "hostlist-server.h"
30 #include "gnunet_hello_lib.h"
31 #include "gnunet_peerinfo_service.h"
32 #include "gnunet-daemon-hostlist.h"
33 #include "gnunet_resolver_service.h"
35 #define DEBUG_HOSTLIST_SERVER GNUNET_NO
38 * How often should we recalculate our response to hostlist requests?
40 #define RESPONSE_UPDATE_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 5)
43 * Handle to the HTTP server as provided by libmicrohttpd for IPv6.
45 static struct MHD_Daemon *daemon_handle_v6;
48 * Handle to the HTTP server as provided by libmicrohttpd for IPv4.
50 static struct MHD_Daemon *daemon_handle_v4;
55 static const struct GNUNET_CONFIGURATION_Handle *cfg;
60 static struct GNUNET_SCHEDULER_Handle *sched;
63 * For keeping statistics.
65 static struct GNUNET_STATISTICS_Handle *stats;
68 * Handle to the core service (NULL until we've connected to it).
70 struct GNUNET_CORE_Handle *core;
73 * Our primary task for IPv4.
75 static GNUNET_SCHEDULER_TaskIdentifier hostlist_task_v4;
78 * Our primary task for IPv6.
80 static GNUNET_SCHEDULER_TaskIdentifier hostlist_task_v6;
83 * Task that updates our HTTP response.
85 static GNUNET_SCHEDULER_TaskIdentifier response_task;
88 * Our canonical response.
90 static struct MHD_Response *response;
93 * NULL if we are not currenlty iterating over peer information.
95 static struct GNUNET_PEERINFO_IteratorContext *pitr;
98 * Context for host processor.
108 * Task that will produce a new response object.
111 update_response (void *cls,
112 const struct GNUNET_SCHEDULER_TaskContext *tc);
115 * Function that assembles our response.
118 finish_response (struct HostSet *results)
120 struct GNUNET_TIME_Relative freq;
122 if (response != NULL)
123 MHD_destroy_response (response);
124 #if DEBUG_HOSTLIST_SERVER
125 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
126 "Creating hostlist response with %u bytes\n",
127 (unsigned int) results->size);
129 response = MHD_create_response_from_data (results->size,
130 results->data, MHD_YES, MHD_NO);
131 if ( (daemon_handle_v4 != NULL) ||
132 (daemon_handle_v6 != NULL) )
134 freq = RESPONSE_UPDATE_FREQUENCY;
135 if (results->size == 0)
136 freq = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, 250);
137 /* schedule next update of the response */
138 response_task = GNUNET_SCHEDULER_add_delayed (sched,
145 /* already past shutdown */
146 MHD_destroy_response (response);
149 GNUNET_STATISTICS_set (stats,
150 gettext_noop("bytes in hostlist"),
153 GNUNET_free (results);
158 * Set 'cls' to GNUNET_YES (we have an address!).
160 * @param cls closure, an 'int*'
161 * @param tname name of the transport (ignored)
162 * @param expiration expiration time (call is ignored if this is in the past)
163 * @param addr the address (ignored)
164 * @param addrlen length of the address (ignored)
165 * @return GNUNET_SYSERR to stop iterating (unless expiration has occured)
168 check_has_addr (void *cls,
170 struct GNUNET_TIME_Absolute expiration,
171 const void *addr, size_t addrlen)
175 if (GNUNET_TIME_absolute_get_remaining (expiration).value == 0)
177 GNUNET_STATISTICS_update (stats,
178 gettext_noop("expired addresses encountered"),
181 return GNUNET_YES; /* ignore this address */
184 return GNUNET_SYSERR;
189 * Callback that processes each of the known HELLOs for the
190 * hostlist response construction.
193 host_processor (void *cls,
194 const struct GNUNET_PeerIdentity * peer,
195 const struct GNUNET_HELLO_Message *hello,
198 struct HostSet *results = cls;
206 finish_response (results);
209 has_addr = GNUNET_NO;
210 GNUNET_HELLO_iterate_addresses (hello,
214 if (GNUNET_NO == has_addr)
216 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
217 "HELLO for peer `%4s' has no address, not suitable for hostlist!\n",
219 GNUNET_STATISTICS_update (stats,
220 gettext_noop("HELLOs without addresses encountered (ignored)"),
226 s = GNUNET_HELLO_size(hello);
227 #if DEBUG_HOSTLIST_SERVER
228 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
229 "Received %u bytes of `%s' from peer `%s' for hostlist.\n",
234 if (old + s >= GNUNET_MAX_MALLOC_CHECKED)
236 GNUNET_STATISTICS_update (stats,
237 gettext_noop("bytes not included in hostlist (size limit)"),
240 return; /* too large, skip! */
242 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
243 "Adding peer `%s' to hostlist (%u bytes)\n",
246 GNUNET_array_grow (results->data,
249 memcpy (&results->data[old], hello, s);
254 * Task that will produce a new response object.
257 update_response (void *cls,
258 const struct GNUNET_SCHEDULER_TaskContext *tc)
260 struct HostSet *results;
262 response_task = GNUNET_SCHEDULER_NO_TASK;
263 results = GNUNET_malloc(sizeof(struct HostSet));
264 pitr = GNUNET_PEERINFO_iterate (cfg, sched,
267 GNUNET_TIME_UNIT_MINUTES,
274 * Hostlist access policy (very permissive, allows everything).
277 accept_policy_callback (void *cls,
278 const struct sockaddr *addr, socklen_t addrlen)
280 if (NULL == response)
282 #if DEBUG_HOSTLIST_SERVER
283 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
284 "Received request for hostlist, but I am not yet ready; rejecting!\n");
288 return MHD_YES; /* accept all */
293 * Main request handler.
296 access_handler_callback (void *cls,
297 struct MHD_Connection *connection,
301 const char *upload_data,
302 size_t*upload_data_size, void **con_cls)
306 if (0 != strcmp (method, MHD_HTTP_METHOD_GET))
308 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
309 _("Refusing `%s' request to hostlist server\n"),
311 GNUNET_STATISTICS_update (stats,
312 gettext_noop("hostlist requests refused (not HTTP GET)"),
317 if (NULL == *con_cls)
320 #if DEBUG_HOSTLIST_SERVER
321 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
322 _("Sending 100 CONTINUE reply\n"));
324 return MHD_YES; /* send 100 continue */
326 if (*upload_data_size != 0)
328 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
329 _("Refusing `%s' request with %llu bytes of upload data\n"),
331 (unsigned long long) *upload_data_size);
332 GNUNET_STATISTICS_update (stats,
333 gettext_noop("hostlist requests refused (upload data)"),
336 return MHD_NO; /* do not support upload data */
338 if (response == NULL)
340 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
341 _("Could not handle hostlist request since I do not have a response yet\n"));
342 GNUNET_STATISTICS_update (stats,
343 gettext_noop("hostlist requests refused (not ready)"),
346 return MHD_NO; /* internal error, no response yet */
348 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
349 _("Received request for our hostlist\n"));
350 GNUNET_STATISTICS_update (stats,
351 gettext_noop("hostlist requests processed"),
354 return MHD_queue_response (connection, MHD_HTTP_OK, response);
358 adv_transmit_ready ( void *cls, size_t size, void *buf)
360 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
361 _("Ready to transmit %u bytes of adv\n"), size);
366 adv_transmit_message ( const struct GNUNET_PeerIdentity * peer, int size )
368 /* transmit message to peer */
371 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
372 _("Not connected to core, unable to send advertisement message\n"));
376 struct GNUNET_TIME_Relative timeout = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, GNUNET_ADV_TIMEOUT);
377 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
378 _("Asked to transmit %u bytes of adv\n"), size);
379 GNUNET_CORE_notify_transmit_ready (core,
384 &adv_transmit_ready, NULL);
389 * Function that assembles our hostlist adv message.
392 adv_create_message ( const struct GNUNET_PeerIdentity * peer,
393 struct GNUNET_HOSTLIST_ADV_Message * adv_msg )
398 unsigned long long port;
401 char hostname[HOST_NAME_MAX];
402 char *protocol = "http://";
403 char *port_s = GNUNET_malloc(6 * sizeof(char));
405 if (0 != gethostname (hostname, sizeof (hostname) - 1))
407 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
408 "Could not get system's hostname, unable to create advertisement message");
411 if (-1 == GNUNET_CONFIGURATION_get_value_number (cfg,
415 return GNUNET_SYSERR;
417 sprintf(port_s, "%llu", port);
418 length = strlen(hostname)+strlen(protocol)+strlen(port_s)+2;
419 size = (length+1) * sizeof (char);
420 uri = GNUNET_malloc(size);
421 uri = strcpy(uri, protocol);
422 uri = strcat(uri, hostname);
423 uri = strcat(uri, ":");
424 uri = strcat(uri, port_s);
425 uri = strcat(uri, "/");
426 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Address to obtain hostlist: %s\n", uri);
429 adv_msg = GNUNET_malloc ( sizeof(struct GNUNET_HOSTLIST_ADV_Message) + size);
431 GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
432 "Creating message:address null\n",sizeof(struct GNUNET_HOSTLIST_ADV_Message));
434 if ( NULL == adv_msg)
436 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
437 "Could not allocate memory for the message");
440 GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
441 "size ADV_Message: %u\n",sizeof(struct GNUNET_HOSTLIST_ADV_Message));
442 GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
443 "size uri: %u\n", (length + 1) * sizeof (char));
446 if ( ( size + sizeof( struct GNUNET_HOSTLIST_ADV_Message )) > GNUNET_SERVER_MAX_MESSAGE_SIZE)
448 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
449 "Advertisement message is bigger than GNUNET allows");
453 adv_msg->header.type = htons (GNUNET_MESSAGE_TYPE_HOSTLIST_ADVERTISEMENT);
454 adv_msg->header.size = htons (sizeof (struct GNUNET_HOSTLIST_ADV_Message) + size);
455 memcpy(&adv_msg[1],uri,size);
457 /* Request core to transmit message to peer
458 adv_transmit_message(peer, size); */
460 GNUNET_free ( port_s );
462 GNUNET_free ( adv_msg );
468 * Method called whenever a given peer connects.
471 * @param peer peer identity this notification is about
472 * @param latency reported latency of the connection with 'other'
473 * @param distance reported distance (DV) to 'other'
476 connect_handler (void *cls,
478 GNUNET_PeerIdentity * peer,
479 struct GNUNET_TIME_Relative latency,
483 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
484 "A new peer connected to the server, preparing to send hostlist advertisement\n");
485 /* create a new advertisement message */
486 struct GNUNET_HOSTLIST_ADV_Message *adv_msg = NULL;
487 if ( (GNUNET_OK != adv_create_message(peer, adv_msg)))
489 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
490 _(" GNUNET_OK Could not create a hostlist advertisement message, impossible to advertise hostlist\n"));
497 * Method called whenever a given peer disconnects.
500 * @param peer peer identity this notification is about
503 disconnect_handler (void *cls,
505 GNUNET_PeerIdentity * peer)
512 * Function that queries MHD's select sets and
513 * starts the task waiting for them.
515 static GNUNET_SCHEDULER_TaskIdentifier
516 prepare_daemon (struct MHD_Daemon *daemon_handle);
519 * Call MHD to process pending requests and then go back
520 * and schedule the next run.
523 run_daemon (void *cls,
524 const struct GNUNET_SCHEDULER_TaskContext *tc)
526 struct MHD_Daemon *daemon_handle = cls;
528 if (daemon_handle == daemon_handle_v4)
529 hostlist_task_v4 = GNUNET_SCHEDULER_NO_TASK;
531 hostlist_task_v6 = GNUNET_SCHEDULER_NO_TASK;
533 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
535 GNUNET_assert (MHD_YES == MHD_run (daemon_handle));
536 if (daemon_handle == daemon_handle_v4)
537 hostlist_task_v4 = prepare_daemon (daemon_handle);
539 hostlist_task_v6 = prepare_daemon (daemon_handle);
544 * Function that queries MHD's select sets and
545 * starts the task waiting for them.
547 static GNUNET_SCHEDULER_TaskIdentifier
548 prepare_daemon (struct MHD_Daemon *daemon_handle)
550 GNUNET_SCHEDULER_TaskIdentifier ret;
554 struct GNUNET_NETWORK_FDSet *wrs;
555 struct GNUNET_NETWORK_FDSet *wws;
556 struct GNUNET_NETWORK_FDSet *wes;
558 unsigned long long timeout;
560 struct GNUNET_TIME_Relative tv;
565 wrs = GNUNET_NETWORK_fdset_create ();
566 wes = GNUNET_NETWORK_fdset_create ();
567 wws = GNUNET_NETWORK_fdset_create ();
569 GNUNET_assert (MHD_YES ==
570 MHD_get_fdset (daemon_handle,
575 haveto = MHD_get_timeout (daemon_handle, &timeout);
576 if (haveto == MHD_YES)
577 tv.value = (uint64_t) timeout;
579 tv = GNUNET_TIME_UNIT_FOREVER_REL;
580 GNUNET_NETWORK_fdset_copy_native (wrs, &rs, max);
581 GNUNET_NETWORK_fdset_copy_native (wws, &ws, max);
582 GNUNET_NETWORK_fdset_copy_native (wes, &es, max);
583 ret = GNUNET_SCHEDULER_add_select (sched,
584 GNUNET_SCHEDULER_PRIORITY_HIGH,
585 GNUNET_SCHEDULER_NO_TASK,
591 GNUNET_NETWORK_fdset_destroy (wrs);
592 GNUNET_NETWORK_fdset_destroy (wws);
593 GNUNET_NETWORK_fdset_destroy (wes);
600 * Start server offering our hostlist.
602 * @return GNUNET_OK on success
605 GNUNET_HOSTLIST_server_start (const struct GNUNET_CONFIGURATION_Handle *c,
606 struct GNUNET_SCHEDULER_Handle *s,
607 struct GNUNET_STATISTICS_Handle *st,
608 struct GNUNET_CORE_Handle *co,
609 GNUNET_CORE_ConnectEventHandler *server_ch,
610 GNUNET_CORE_DisconnectEventHandler *server_dh)
612 unsigned long long port;
617 if (-1 == GNUNET_CONFIGURATION_get_value_number (cfg,
621 return GNUNET_SYSERR;
622 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
623 _("Hostlist service starts on port %llu\n"),
625 daemon_handle_v6 = MHD_start_daemon (MHD_USE_IPv6
626 #if DEBUG_HOSTLIST_SERVER
630 (unsigned short) port,
631 &accept_policy_callback,
633 &access_handler_callback,
635 MHD_OPTION_CONNECTION_LIMIT, (unsigned int) 16,
636 MHD_OPTION_PER_IP_CONNECTION_LIMIT, (unsigned int) 1,
637 MHD_OPTION_CONNECTION_TIMEOUT, (unsigned int) 16,
638 MHD_OPTION_CONNECTION_MEMORY_LIMIT, (size_t) (16 * 1024),
640 daemon_handle_v4 = MHD_start_daemon (MHD_NO_FLAG
641 #if DEBUG_HOSTLIST_SERVER
645 (unsigned short) port,
646 &accept_policy_callback,
648 &access_handler_callback,
650 MHD_OPTION_CONNECTION_LIMIT, (unsigned int) 16,
651 MHD_OPTION_PER_IP_CONNECTION_LIMIT, (unsigned int) 1,
652 MHD_OPTION_CONNECTION_TIMEOUT, (unsigned int) 16,
653 MHD_OPTION_CONNECTION_MEMORY_LIMIT, (size_t) (16 * 1024),
656 if ( (daemon_handle_v6 == NULL) &&
657 (daemon_handle_v4 == NULL) )
659 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
660 _("Could not start hostlist HTTP server on port %u\n"),
661 (unsigned short) port);
662 return GNUNET_SYSERR;
665 *server_ch = &connect_handler;
666 *server_dh = &disconnect_handler;
668 if (daemon_handle_v4 != NULL)
669 hostlist_task_v4 = prepare_daemon (daemon_handle_v4);
670 if (daemon_handle_v6 != NULL)
671 hostlist_task_v6 = prepare_daemon (daemon_handle_v6);
672 response_task = GNUNET_SCHEDULER_add_now (sched,
679 * Stop server offering our hostlist.
682 GNUNET_HOSTLIST_server_stop ()
684 #if DEBUG_HOSTLIST_SERVER
685 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
686 "Hostlist server shutdown\n");
688 if (GNUNET_SCHEDULER_NO_TASK != hostlist_task_v6)
690 GNUNET_SCHEDULER_cancel (sched, hostlist_task_v6);
691 hostlist_task_v6 = GNUNET_SCHEDULER_NO_TASK;
693 if (GNUNET_SCHEDULER_NO_TASK != hostlist_task_v4)
695 GNUNET_SCHEDULER_cancel (sched, hostlist_task_v4);
696 hostlist_task_v4 = GNUNET_SCHEDULER_NO_TASK;
700 GNUNET_PEERINFO_iterate_cancel (pitr);
703 if (GNUNET_SCHEDULER_NO_TASK != response_task)
705 GNUNET_SCHEDULER_cancel (sched, response_task);
706 response_task = GNUNET_SCHEDULER_NO_TASK;
708 if (NULL != daemon_handle_v4)
710 MHD_stop_daemon (daemon_handle_v4);
711 daemon_handle_v4 = NULL;
713 if (NULL != daemon_handle_v6)
715 MHD_stop_daemon (daemon_handle_v6);
716 daemon_handle_v6 = NULL;
718 if (response != NULL)
720 MHD_destroy_response (response);
725 /* end of hostlist-server.c */