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);
211 has_addr = GNUNET_NO;
212 GNUNET_HELLO_iterate_addresses (hello,
216 if (GNUNET_NO == has_addr)
218 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
219 "HELLO for peer `%4s' has no address, not suitable for hostlist!\n",
221 GNUNET_STATISTICS_update (stats,
222 gettext_noop("HELLOs without addresses encountered (ignored)"),
228 s = GNUNET_HELLO_size(hello);
229 #if DEBUG_HOSTLIST_SERVER
230 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
231 "Received %u bytes of `%s' from peer `%s' for hostlist.\n",
236 if (old + s >= GNUNET_MAX_MALLOC_CHECKED)
238 GNUNET_STATISTICS_update (stats,
239 gettext_noop("bytes not included in hostlist (size limit)"),
242 return; /* too large, skip! */
244 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
245 "Adding peer `%s' to hostlist (%u bytes)\n",
248 GNUNET_array_grow (results->data,
251 memcpy (&results->data[old], hello, s);
256 * Task that will produce a new response object.
259 update_response (void *cls,
260 const struct GNUNET_SCHEDULER_TaskContext *tc)
262 struct HostSet *results;
264 response_task = GNUNET_SCHEDULER_NO_TASK;
265 results = GNUNET_malloc(sizeof(struct HostSet));
266 pitr = GNUNET_PEERINFO_iterate (cfg, sched,
269 GNUNET_TIME_UNIT_MINUTES,
276 * Hostlist access policy (very permissive, allows everything).
279 accept_policy_callback (void *cls,
280 const struct sockaddr *addr, socklen_t addrlen)
282 if (NULL == response)
284 #if DEBUG_HOSTLIST_SERVER
285 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
286 "Received request for hostlist, but I am not yet ready; rejecting!\n");
290 return MHD_YES; /* accept all */
295 * Main request handler.
298 access_handler_callback (void *cls,
299 struct MHD_Connection *connection,
303 const char *upload_data,
304 size_t*upload_data_size, void **con_cls)
308 if (0 != strcmp (method, MHD_HTTP_METHOD_GET))
310 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
311 _("Refusing `%s' request to hostlist server\n"),
313 GNUNET_STATISTICS_update (stats,
314 gettext_noop("hostlist requests refused (not HTTP GET)"),
319 if (NULL == *con_cls)
322 #if DEBUG_HOSTLIST_SERVER
323 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
324 _("Sending 100 CONTINUE reply\n"));
326 return MHD_YES; /* send 100 continue */
328 if (*upload_data_size != 0)
330 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
331 _("Refusing `%s' request with %llu bytes of upload data\n"),
333 (unsigned long long) *upload_data_size);
334 GNUNET_STATISTICS_update (stats,
335 gettext_noop("hostlist requests refused (upload data)"),
338 return MHD_NO; /* do not support upload data */
340 if (response == NULL)
342 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
343 _("Could not handle hostlist request since I do not have a response yet\n"));
344 GNUNET_STATISTICS_update (stats,
345 gettext_noop("hostlist requests refused (not ready)"),
348 return MHD_NO; /* internal error, no response yet */
350 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
351 _("Received request for our hostlist\n"));
352 GNUNET_STATISTICS_update (stats,
353 gettext_noop("hostlist requests processed"),
356 return MHD_queue_response (connection, MHD_HTTP_OK, response);
359 struct GNUNET_HOSTLIST_ADV_Message adv_message;
360 char hostlist_uri[1024];
363 adv_transmit_ready ( void *cls, size_t size, void *buf)
365 int transmission_size;
367 transmission_size = sizeof (struct GNUNET_HOSTLIST_ADV_Message) + strlen(hostlist_uri) +1;
368 adv_message.header.size = htons (transmission_size);
370 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
371 "Assembled message size %u\n", transmission_size);
372 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
373 "Size Messageheader %u\n", sizeof (struct GNUNET_HOSTLIST_ADV_Message));
374 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
375 "Size URI %u\n", strlen(hostlist_uri));
378 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Transmission failed, buffer invalid!\n");
381 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
382 _("Buffer valid of size %u\n"), size);
384 if (size >= transmission_size)
386 memcpy(buf, &adv_message, transmission_size);
388 GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Sent advertisement message: Copied %d bytes into buffer!\n\n\n", transmission_size);
390 return transmission_size;
397 adv_transmit_message ( const struct GNUNET_PeerIdentity * peer, int size )
399 /* transmit message to peer */
402 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
403 _("Not connected to core, unable to send advertisement message\n"));
407 struct GNUNET_TIME_Relative timeout = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, GNUNET_ADV_TIMEOUT);
408 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
409 _("Asked to transmit %u bytes of adv\n"), size);
410 struct GNUNET_CORE_TransmitHandle * th;
411 th = GNUNET_CORE_notify_transmit_ready (core,
416 &adv_transmit_ready, NULL);
418 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
419 _("Advertisement message could not be queued by core\n"));
426 * Function that assembles our hostlist adv message.
429 adv_create_message ( const struct GNUNET_PeerIdentity * peer )
434 unsigned long long port;
437 char hostname[GNUNET_OS_get_hostname_max_length() + 1];
438 char *protocol = "http://";
439 char *port_s = GNUNET_malloc(6 * sizeof(char));
441 if (0 != gethostname (hostname, sizeof (hostname) - 1))
443 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
444 "Could not get system's hostname, unable to create advertisement message");
447 if (-1 == GNUNET_CONFIGURATION_get_value_number (cfg,
451 return GNUNET_SYSERR;
453 sprintf(port_s, "%llu", port);
454 length = strlen(hostname)+strlen(protocol)+strlen(port_s)+2;
455 size = (length+1) * sizeof (char);
456 uri = GNUNET_malloc(size);
457 uri = strcpy(uri, protocol);
458 uri = strcat(uri, hostname);
459 uri = strcat(uri, ":");
460 uri = strcat(uri, port_s);
461 uri = strcat(uri, "/");
462 strcpy(hostlist_uri,uri);
463 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Address to obtain hostlist: %s\n", uri);
466 /* adv_msg = GNUNET_malloc ( sizeof(struct GNUNET_HOSTLIST_ADV_Message) + size);
468 GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
469 "Creating message:address null\n",sizeof(struct GNUNET_HOSTLIST_ADV_Message));
471 if ( NULL == adv_msg)
473 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
474 "Could not allocate memory for the message");
479 if ( ( size + sizeof( struct GNUNET_HOSTLIST_ADV_Message )) > GNUNET_SERVER_MAX_MESSAGE_SIZE)
481 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
482 "Advertisement message is bigger than GNUNET allows");
486 //adv_msg->header.type = htons (GNUNET_MESSAGE_TYPE_HOSTLIST_ADVERTISEMENT);
487 //adv_msg->header.size = htons (sizeof (struct GNUNET_HOSTLIST_ADV_Message) + size);
488 // memcpy(&adv_msg[1],uri,size);
490 adv_message.header.type = htons (GNUNET_MESSAGE_TYPE_HOSTLIST_ADVERTISEMENT);
492 /* Request core to transmit message to peer */
493 size = size + sizeof(struct GNUNET_HOSTLIST_ADV_Message);
494 adv_transmit_message(peer, size);
496 GNUNET_free ( port_s );
498 //GNUNET_free ( adv_msg );
504 * Method called whenever a given peer connects.
507 * @param peer peer identity this notification is about
508 * @param latency reported latency of the connection with 'other'
509 * @param distance reported distance (DV) to 'other'
512 connect_handler (void *cls,
514 GNUNET_PeerIdentity * peer,
515 struct GNUNET_TIME_Relative latency,
518 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
519 "A new peer connected to the server, preparing to send hostlist advertisement\n");
520 /* create a new advertisement message */
521 if ( (GNUNET_OK != adv_create_message(peer)))
523 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
524 _(" GNUNET_OK Could not create a hostlist advertisement message, impossible to advertise hostlist\n"));
531 * Method called whenever a given peer disconnects.
534 * @param peer peer identity this notification is about
537 disconnect_handler (void *cls,
539 GNUNET_PeerIdentity * peer)
546 * Function that queries MHD's select sets and
547 * starts the task waiting for them.
549 static GNUNET_SCHEDULER_TaskIdentifier
550 prepare_daemon (struct MHD_Daemon *daemon_handle);
553 * Call MHD to process pending requests and then go back
554 * and schedule the next run.
557 run_daemon (void *cls,
558 const struct GNUNET_SCHEDULER_TaskContext *tc)
560 struct MHD_Daemon *daemon_handle = cls;
562 if (daemon_handle == daemon_handle_v4)
563 hostlist_task_v4 = GNUNET_SCHEDULER_NO_TASK;
565 hostlist_task_v6 = GNUNET_SCHEDULER_NO_TASK;
567 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
569 GNUNET_assert (MHD_YES == MHD_run (daemon_handle));
570 if (daemon_handle == daemon_handle_v4)
571 hostlist_task_v4 = prepare_daemon (daemon_handle);
573 hostlist_task_v6 = prepare_daemon (daemon_handle);
578 * Function that queries MHD's select sets and
579 * starts the task waiting for them.
581 static GNUNET_SCHEDULER_TaskIdentifier
582 prepare_daemon (struct MHD_Daemon *daemon_handle)
584 GNUNET_SCHEDULER_TaskIdentifier ret;
588 struct GNUNET_NETWORK_FDSet *wrs;
589 struct GNUNET_NETWORK_FDSet *wws;
590 struct GNUNET_NETWORK_FDSet *wes;
592 unsigned long long timeout;
594 struct GNUNET_TIME_Relative tv;
599 wrs = GNUNET_NETWORK_fdset_create ();
600 wes = GNUNET_NETWORK_fdset_create ();
601 wws = GNUNET_NETWORK_fdset_create ();
603 GNUNET_assert (MHD_YES ==
604 MHD_get_fdset (daemon_handle,
609 haveto = MHD_get_timeout (daemon_handle, &timeout);
610 if (haveto == MHD_YES)
611 tv.value = (uint64_t) timeout;
613 tv = GNUNET_TIME_UNIT_FOREVER_REL;
614 GNUNET_NETWORK_fdset_copy_native (wrs, &rs, max);
615 GNUNET_NETWORK_fdset_copy_native (wws, &ws, max);
616 GNUNET_NETWORK_fdset_copy_native (wes, &es, max);
617 ret = GNUNET_SCHEDULER_add_select (sched,
618 GNUNET_SCHEDULER_PRIORITY_HIGH,
619 GNUNET_SCHEDULER_NO_TASK,
625 GNUNET_NETWORK_fdset_destroy (wrs);
626 GNUNET_NETWORK_fdset_destroy (wws);
627 GNUNET_NETWORK_fdset_destroy (wes);
634 * Start server offering our hostlist.
636 * @return GNUNET_OK on success
639 GNUNET_HOSTLIST_server_start (const struct GNUNET_CONFIGURATION_Handle *c,
640 struct GNUNET_SCHEDULER_Handle *s,
641 struct GNUNET_STATISTICS_Handle *st,
642 struct GNUNET_CORE_Handle *co,
643 GNUNET_CORE_ConnectEventHandler *server_ch,
644 GNUNET_CORE_DisconnectEventHandler *server_dh)
646 unsigned long long port;
651 if (-1 == GNUNET_CONFIGURATION_get_value_number (cfg,
655 return GNUNET_SYSERR;
656 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
657 _("Hostlist service starts on port %llu\n"),
659 daemon_handle_v6 = MHD_start_daemon (MHD_USE_IPv6
660 #if DEBUG_HOSTLIST_SERVER
664 (unsigned short) port,
665 &accept_policy_callback,
667 &access_handler_callback,
669 MHD_OPTION_CONNECTION_LIMIT, (unsigned int) 16,
670 MHD_OPTION_PER_IP_CONNECTION_LIMIT, (unsigned int) 1,
671 MHD_OPTION_CONNECTION_TIMEOUT, (unsigned int) 16,
672 MHD_OPTION_CONNECTION_MEMORY_LIMIT, (size_t) (16 * 1024),
674 daemon_handle_v4 = MHD_start_daemon (MHD_NO_FLAG
675 #if DEBUG_HOSTLIST_SERVER
679 (unsigned short) port,
680 &accept_policy_callback,
682 &access_handler_callback,
684 MHD_OPTION_CONNECTION_LIMIT, (unsigned int) 16,
685 MHD_OPTION_PER_IP_CONNECTION_LIMIT, (unsigned int) 1,
686 MHD_OPTION_CONNECTION_TIMEOUT, (unsigned int) 16,
687 MHD_OPTION_CONNECTION_MEMORY_LIMIT, (size_t) (16 * 1024),
690 if ( (daemon_handle_v6 == NULL) &&
691 (daemon_handle_v4 == NULL) )
693 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
694 _("Could not start hostlist HTTP server on port %u\n"),
695 (unsigned short) port);
696 return GNUNET_SYSERR;
701 *server_ch = &connect_handler;
702 *server_dh = &disconnect_handler;
704 if (daemon_handle_v4 != NULL)
705 hostlist_task_v4 = prepare_daemon (daemon_handle_v4);
706 if (daemon_handle_v6 != NULL)
707 hostlist_task_v6 = prepare_daemon (daemon_handle_v6);
708 response_task = GNUNET_SCHEDULER_add_now (sched,
715 * Stop server offering our hostlist.
718 GNUNET_HOSTLIST_server_stop ()
720 #if DEBUG_HOSTLIST_SERVER
721 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
722 "Hostlist server shutdown\n");
724 if (GNUNET_SCHEDULER_NO_TASK != hostlist_task_v6)
726 GNUNET_SCHEDULER_cancel (sched, hostlist_task_v6);
727 hostlist_task_v6 = GNUNET_SCHEDULER_NO_TASK;
729 if (GNUNET_SCHEDULER_NO_TASK != hostlist_task_v4)
731 GNUNET_SCHEDULER_cancel (sched, hostlist_task_v4);
732 hostlist_task_v4 = GNUNET_SCHEDULER_NO_TASK;
736 GNUNET_PEERINFO_iterate_cancel (pitr);
739 if (GNUNET_SCHEDULER_NO_TASK != response_task)
741 GNUNET_SCHEDULER_cancel (sched, response_task);
742 response_task = GNUNET_SCHEDULER_NO_TASK;
744 if (NULL != daemon_handle_v4)
746 MHD_stop_daemon (daemon_handle_v4);
747 daemon_handle_v4 = NULL;
749 if (NULL != daemon_handle_v6)
751 MHD_stop_daemon (daemon_handle_v6);
752 daemon_handle_v6 = NULL;
754 if (response != NULL)
756 MHD_destroy_response (response);
761 /* end of hostlist-server.c */