2 This file is part of GNUnet.
3 (C) 2001, 2002, 2003, 2004, 2005, 2006, 2009, 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 3, or (at your
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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 hostlist/hostlist-client.c
23 * @brief hostlist support. Downloads HELLOs via HTTP.
24 * @author Christian Grothoff
25 * @author Matthias Wachs
29 #include "hostlist-client.h"
30 #include "gnunet_core_service.h"
31 #include "gnunet_hello_lib.h"
32 #include "gnunet_statistics_service.h"
33 #include "gnunet_transport_service.h"
34 #include "gnunet-daemon-hostlist.h"
35 #include <curl/curl.h>
36 #include "gnunet_util_lib.h"
40 * Number of connections that we must have to NOT download
43 #define MIN_CONNECTIONS 4
46 * Interval between two advertised hostlist tests
48 #define TESTING_INTERVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
51 * A single hostlist obtained by hostlist advertisements
56 * previous entry, used to manage entries in a double linked list
58 struct Hostlist *prev;
61 * next entry, used to manage entries in a double linked list
63 struct Hostlist *next;
66 * URI where hostlist can be obtained
68 const char *hostlist_uri;
71 * Value describing the quality of the hostlist, the bigger the better but (should) never < 0
72 * used for deciding which hostlist is replaced if MAX_NUMBER_HOSTLISTS in data structure is reached
73 * intial value = HOSTLIST_INITIAL
74 * increased every successful download by HOSTLIST_SUCCESSFULL_DOWNLOAD
75 * increased every successful download by number of obtained HELLO messages
76 * decreased every failed download by HOSTLIST_SUCCESSFULL_DOWNLOAD
81 * Time the hostlist advertisement was recieved and the entry was created
83 struct GNUNET_TIME_Absolute time_creation;
86 * Last time the hostlist was obtained
88 struct GNUNET_TIME_Absolute time_last_usage;
91 * Number of HELLO messages obtained during last download
96 * Number of times the hostlist was successfully obtained
106 static const struct GNUNET_CONFIGURATION_Handle *cfg;
111 static struct GNUNET_STATISTICS_Handle *stats;
116 static struct GNUNET_TRANSPORT_Handle *transport;
119 * Proxy that we are using (can be NULL).
124 * Number of bytes valid in 'download_buffer'.
126 static size_t download_pos;
129 * Current URL that we are using.
131 static char *current_url;
134 * Current CURL handle.
139 * Current multi-CURL handle.
144 * How many bytes did we download from the current hostlist URL?
146 static uint32_t stat_bytes_downloaded;
149 * Amount of time we wait between hostlist downloads.
151 static struct GNUNET_TIME_Relative hostlist_delay;
154 * ID of the task, checking if hostlist download should take plate
156 static GNUNET_SCHEDULER_TaskIdentifier ti_check_download;
159 * ID of the task downloading the hostlist
161 static GNUNET_SCHEDULER_TaskIdentifier ti_download;
164 * ID of the task saving the hostlsit in a regular intervall
166 static GNUNET_SCHEDULER_TaskIdentifier ti_saving_task;
169 * ID of the task called to initiate a download
171 static GNUNET_SCHEDULER_TaskIdentifier ti_download_dispatcher_task;
174 * ID of the task controlling the locking between two hostlist tests
176 static GNUNET_SCHEDULER_TaskIdentifier ti_testing_intervall_task;
179 * At what time MUST the current hostlist request be done?
181 static struct GNUNET_TIME_Absolute end_time;
184 * Head of the linked list used to store hostlists
186 static struct Hostlist *linked_list_head;
189 * Tail of the linked list used to store hostlists
191 static struct Hostlist *linked_list_tail;
194 * Current hostlist used for downloading
196 static struct Hostlist *current_hostlist;
199 * Size of the linke list used to store hostlists
201 static unsigned int linked_list_size;
204 * Head of the linked list used to store hostlists
206 static struct Hostlist *hostlist_to_test;
209 * Handle for our statistics GET operation.
211 static struct GNUNET_STATISTICS_GetHandle *sget;
214 * Set to GNUNET_YES if the current URL had some problems.
216 static int stat_bogus_url;
219 * Value controlling if a hostlist is tested at the moment
221 static int stat_testing_hostlist;
224 * Value controlling if a hostlist testing is allowed at the moment
226 static int stat_testing_allowed;
229 * Value controlling if a hostlist download is running at the moment
231 static int stat_download_in_progress;
234 * Value saying if a preconfigured bootstrap server is used
236 static unsigned int stat_use_bootstrap;
239 * Set if we are allowed to learn new hostlists and use them
241 static int stat_learning;
244 * Value saying if hostlist download was successful
246 static unsigned int stat_download_successful;
249 * Value saying how many valid HELLO messages were obtained during download
251 static unsigned int stat_hellos_obtained;
254 * Number of active connections (according to core service).
256 static unsigned int stat_connection_count;
260 * Process downloaded bits by calling callback on each HELLO.
262 * @param ptr buffer with downloaded data
263 * @param size size of a record
264 * @param nmemb number of records downloaded
266 * @return number of bytes that were processed (always size*nmemb)
269 callback_download (void *ptr, size_t size, size_t nmemb, void *ctx)
271 static char download_buffer[GNUNET_SERVER_MAX_MESSAGE_SIZE - 1];
272 const char *cbuf = ptr;
273 const struct GNUNET_MessageHeader *msg;
279 total = size * nmemb;
280 stat_bytes_downloaded += total;
281 if ((total == 0) || (stat_bogus_url))
283 return total; /* ok, no data or bogus data */
286 GNUNET_STATISTICS_update (stats,
288 ("# bytes downloaded from hostlist servers"),
289 (int64_t) total, GNUNET_NO);
291 while ((left > 0) || (download_pos > 0))
293 cpy = GNUNET_MIN (left, GNUNET_SERVER_MAX_MESSAGE_SIZE - 1 - download_pos);
294 memcpy (&download_buffer[download_pos], cbuf, cpy);
298 if (download_pos < sizeof (struct GNUNET_MessageHeader))
300 GNUNET_assert (0 == left);
303 msg = (const struct GNUNET_MessageHeader *) download_buffer;
304 msize = ntohs (msg->size);
305 if (msize < sizeof (struct GNUNET_MessageHeader))
307 GNUNET_STATISTICS_update (stats,
309 ("# invalid HELLOs downloaded from hostlist servers"),
311 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
312 _("Invalid `%s' message received from hostlist at `%s'\n"),
313 "HELLO", current_url);
314 stat_hellos_obtained++;
318 if (download_pos < msize)
320 GNUNET_assert (left == 0);
323 if (GNUNET_HELLO_size ((const struct GNUNET_HELLO_Message *) msg) == msize)
325 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
326 "Received valid `%s' message from hostlist server.\n",
328 GNUNET_STATISTICS_update (stats,
330 ("# valid HELLOs downloaded from hostlist servers"),
332 stat_hellos_obtained++;
333 GNUNET_TRANSPORT_offer_hello (transport, msg, NULL, NULL);
337 GNUNET_STATISTICS_update (stats,
339 ("# invalid HELLOs downloaded from hostlist servers"),
341 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
342 _("Invalid `%s' message received from hostlist at `%s'\n"),
343 "HELLO", current_url);
344 stat_bogus_url = GNUNET_YES;
345 stat_hellos_obtained++;
348 memmove (download_buffer, &download_buffer[msize], download_pos - msize);
349 download_pos -= msize;
356 * Obtain a hostlist URL that we should use.
358 * @return NULL if there is no URL available
361 get_bootstrap_server ()
369 GNUNET_CONFIGURATION_get_value_string (cfg, "HOSTLIST", "SERVERS",
372 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_WARNING,
373 "hostlist", "SERVERS");
378 if (strlen (servers) > 0)
381 pos = strlen (servers) - 1;
384 if (servers[pos] == ' ')
391 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_WARNING,
392 "hostlist", "SERVERS");
393 GNUNET_free (servers);
397 urls = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, urls) + 1;
398 pos = strlen (servers) - 1;
401 if (servers[pos] == ' ')
413 ret = GNUNET_strdup (&servers[pos]);
414 GNUNET_free (servers);
420 * Method deciding if a preconfigured or advertisied hostlist is used on a 50:50 ratio
421 * @return uri to use, NULL if there is no URL available
427 unsigned int counter;
428 struct Hostlist *pos;
430 if (GNUNET_NO == stat_learning)
432 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
433 "Using preconfigured bootstrap server\n");
434 current_hostlist = NULL;
435 return get_bootstrap_server ();
438 if ((GNUNET_YES == stat_testing_hostlist) && (NULL != hostlist_to_test))
440 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
441 "Testing new advertised hostlist if it is obtainable\n");
442 current_hostlist = hostlist_to_test;
443 return GNUNET_strdup (hostlist_to_test->hostlist_uri);
446 if ((GNUNET_YES == stat_use_bootstrap) || (linked_list_size == 0))
448 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
449 "Using preconfigured bootstrap server\n");
450 current_hostlist = NULL;
451 return get_bootstrap_server ();
454 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, linked_list_size);
456 pos = linked_list_head;
457 while (counter < index)
462 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Using learned hostlist `%s'\n",
464 current_hostlist = pos;
465 return GNUNET_strdup (pos->hostlist_uri);
469 #define CURL_EASY_SETOPT(c, a, b) do { ret = curl_easy_setopt (c, a, b); if (CURLE_OK != ret) GNUNET_log(GNUNET_ERROR_TYPE_WARNING, _("%s failed at %s:%d: `%s'\n"), "curl_easy_setopt", __FILE__, __LINE__, curl_easy_strerror (ret)); } while (0)
473 * Method to save hostlist to a file during hostlist client shutdown
474 * @param shutdown set if called because of shutdown, entries in linked list will be destroyed
477 save_hostlist_file (int shutdown);
481 * add val2 to val1 with overflow check
483 * @param val1 value 1
484 * @param val2 value 2
488 checked_add (uint64_t val1, uint64_t val2)
490 static uint64_t temp;
491 static uint64_t maxv;
504 * Subtract val2 from val1 with underflow check
506 * @param val1 value 1
507 * @param val2 value 2
511 checked_sub (uint64_t val1, uint64_t val2)
515 return (val1 - val2);
520 * Method to check if a URI is in hostlist linked list
522 * @param uri uri to check
523 * @return #GNUNET_YES if existing in linked list, #GNUNET_NO if not
526 linked_list_contains (const char *uri)
528 struct Hostlist *pos;
530 pos = linked_list_head;
533 if (0 == strcmp (pos->hostlist_uri, uri))
542 * Method returning the hostlist element with the lowest quality in the datastore
543 * @return hostlist with lowest quality
545 static struct Hostlist *
546 linked_list_get_lowest_quality ()
548 struct Hostlist *pos;
549 struct Hostlist *lowest;
551 if (linked_list_size == 0)
553 lowest = linked_list_head;
554 pos = linked_list_head->next;
557 if (pos->quality < lowest->quality)
566 * Method to insert a hostlist into the datastore. If datastore
567 * contains maximum number of elements, the elements with lowest
568 * quality is dismissed
573 struct Hostlist *lowest_quality;
575 if (MAX_NUMBER_HOSTLISTS <= linked_list_size)
577 /* No free entries available, replace existing entry */
578 lowest_quality = linked_list_get_lowest_quality ();
579 GNUNET_assert (lowest_quality != NULL);
580 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
581 "Removing hostlist with URI `%s' which has the worst quality of all (%llu)\n",
582 lowest_quality->hostlist_uri,
583 (unsigned long long) lowest_quality->quality);
584 GNUNET_CONTAINER_DLL_remove (linked_list_head, linked_list_tail,
587 GNUNET_free (lowest_quality);
589 GNUNET_CONTAINER_DLL_insert (linked_list_head, linked_list_tail,
592 GNUNET_STATISTICS_set (stats, gettext_noop ("# advertised hostlist URIs"),
593 linked_list_size, GNUNET_NO);
594 stat_testing_hostlist = GNUNET_NO;
599 * Method updating hostlist statistics
606 if (((stat_use_bootstrap == GNUNET_NO) && (NULL != current_hostlist)) ||
607 ((stat_testing_hostlist == GNUNET_YES) && (NULL != current_hostlist)))
609 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
610 "Updating hostlist statics for URI `%s'\n",
611 current_hostlist->hostlist_uri);
612 current_hostlist->hello_count = stat_hellos_obtained;
613 current_hostlist->time_last_usage = GNUNET_TIME_absolute_get ();
614 current_hostlist->quality =
615 checked_add (current_hostlist->quality,
616 (stat_hellos_obtained * HOSTLIST_SUCCESSFUL_HELLO));
617 if (GNUNET_YES == stat_download_successful)
619 current_hostlist->times_used++;
620 current_hostlist->quality =
621 checked_add (current_hostlist->quality, HOSTLIST_SUCCESSFUL_DOWNLOAD);
622 GNUNET_asprintf (&stat, gettext_noop ("# advertised URI `%s' downloaded"),
623 current_hostlist->hostlist_uri);
625 GNUNET_STATISTICS_update (stats, stat, 1, GNUNET_YES);
629 current_hostlist->quality =
630 checked_sub (current_hostlist->quality, HOSTLIST_FAILED_DOWNLOAD);
632 current_hostlist = NULL;
633 /* Alternating the usage of preconfigured and learned hostlists */
635 if (stat_testing_hostlist == GNUNET_YES)
638 if (GNUNET_YES == stat_learning)
640 if (stat_use_bootstrap == GNUNET_YES)
641 stat_use_bootstrap = GNUNET_NO;
643 stat_use_bootstrap = GNUNET_YES;
646 stat_use_bootstrap = GNUNET_YES;
651 * Clean up the state from the task that downloaded the
652 * hostlist and schedule the next task.
659 if ((stat_testing_hostlist == GNUNET_YES) &&
660 (GNUNET_NO == stat_download_successful) && (NULL != hostlist_to_test))
662 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
664 ("Advertised hostlist with URI `%s' could not be downloaded. Advertised URI gets dismissed.\n"),
665 hostlist_to_test->hostlist_uri);
668 if (stat_testing_hostlist == GNUNET_YES)
670 stat_testing_hostlist = GNUNET_NO;
672 if (NULL != hostlist_to_test)
674 GNUNET_free (hostlist_to_test);
675 hostlist_to_test = NULL;
680 mret = curl_multi_remove_handle (multi, curl);
681 if (mret != CURLM_OK)
683 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
684 "curl_multi_remove_handle", __FILE__, __LINE__,
685 curl_multi_strerror (mret));
687 mret = curl_multi_cleanup (multi);
688 if (mret != CURLM_OK)
689 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
690 "curl_multi_cleanup", __FILE__, __LINE__,
691 curl_multi_strerror (mret));
696 curl_easy_cleanup (curl);
699 GNUNET_free_non_null (current_url);
701 stat_bytes_downloaded = 0;
702 stat_download_in_progress = GNUNET_NO;
707 * Task that is run when we are ready to receive more data from the hostlist
710 * @param cls closure, unused
711 * @param tc task context, unused
714 task_download (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
718 * Ask CURL for the select set and then schedule the
719 * receiving task with the scheduler.
729 struct GNUNET_NETWORK_FDSet *grs;
730 struct GNUNET_NETWORK_FDSet *gws;
732 struct GNUNET_TIME_Relative rtime;
738 mret = curl_multi_fdset (multi, &rs, &ws, &es, &max);
739 if (mret != CURLM_OK)
741 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
742 "curl_multi_fdset", __FILE__, __LINE__,
743 curl_multi_strerror (mret));
747 mret = curl_multi_timeout (multi, &timeout);
748 if (mret != CURLM_OK)
750 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
751 "curl_multi_timeout", __FILE__, __LINE__,
752 curl_multi_strerror (mret));
757 GNUNET_TIME_relative_min (GNUNET_TIME_absolute_get_remaining (end_time),
758 GNUNET_TIME_relative_multiply
759 (GNUNET_TIME_UNIT_MILLISECONDS, timeout));
760 grs = GNUNET_NETWORK_fdset_create ();
761 gws = GNUNET_NETWORK_fdset_create ();
762 GNUNET_NETWORK_fdset_copy_native (grs, &rs, max + 1);
763 GNUNET_NETWORK_fdset_copy_native (gws, &ws, max + 1);
764 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
765 "Scheduling task for hostlist download using cURL\n");
767 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT,
769 &task_download, multi);
770 GNUNET_NETWORK_fdset_destroy (gws);
771 GNUNET_NETWORK_fdset_destroy (grs);
776 * Task that is run when we are ready to receive more data from the hostlist
779 * @param cls closure, unused
780 * @param tc task context, unused
783 task_download (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
789 ti_download = GNUNET_SCHEDULER_NO_TASK;
790 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
792 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
793 "Shutdown requested while trying to download hostlist from `%s'\n",
799 if (0 == GNUNET_TIME_absolute_get_remaining (end_time).rel_value_us)
801 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
802 _("Timeout trying to download hostlist from `%s'\n"),
808 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
809 "Ready for processing hostlist client request\n");
813 if (stat_bytes_downloaded > MAX_BYTES_PER_HOSTLISTS)
815 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
816 _("Download limit of %u bytes exceeded, stopping download\n"),
817 MAX_BYTES_PER_HOSTLISTS);
821 mret = curl_multi_perform (multi, &running);
826 msg = curl_multi_info_read (multi, &running);
827 GNUNET_break (msg != NULL);
833 if ((msg->data.result != CURLE_OK) &&
834 (msg->data.result != CURLE_GOT_NOTHING))
835 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
836 _("Download of hostlist from `%s' failed: `%s'\n"),
838 curl_easy_strerror (msg->data.result));
841 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
842 _("Download of hostlist `%s' completed.\n"),
844 stat_download_successful = GNUNET_YES;
846 if (GNUNET_YES == stat_testing_hostlist)
848 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
850 ("Adding successfully tested hostlist `%s' datastore.\n"),
853 hostlist_to_test = NULL;
854 stat_testing_hostlist = GNUNET_NO;
864 while ((running > 0));
867 while (mret == CURLM_CALL_MULTI_PERFORM);
869 if (mret != CURLM_OK)
871 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("%s failed at %s:%d: `%s'\n"),
872 "curl_multi_perform", __FILE__, __LINE__,
873 curl_multi_strerror (mret));
881 * Main function that will download a hostlist and process its
891 current_url = download_get_url ();
892 if (current_url == NULL)
894 curl = curl_easy_init ();
902 GNUNET_log (GNUNET_ERROR_TYPE_INFO | GNUNET_ERROR_TYPE_BULK,
903 _("Bootstrapping using hostlist at `%s'.\n"), current_url);
905 stat_download_in_progress = GNUNET_YES;
906 stat_download_successful = GNUNET_NO;
907 stat_hellos_obtained = 0;
908 stat_bytes_downloaded = 0;
910 GNUNET_STATISTICS_update (stats,
911 gettext_noop ("# hostlist downloads initiated"), 1,
914 CURL_EASY_SETOPT (curl, CURLOPT_PROXY, proxy);
917 CURL_EASY_SETOPT (curl, CURLOPT_WRITEFUNCTION, &callback_download);
923 CURL_EASY_SETOPT (curl, CURLOPT_WRITEDATA, NULL);
929 CURL_EASY_SETOPT (curl, CURLOPT_FOLLOWLOCATION, 1);
930 CURL_EASY_SETOPT (curl, CURLOPT_REDIR_PROTOCOLS, CURLPROTO_HTTP | CURLPROTO_HTTPS);
931 CURL_EASY_SETOPT (curl, CURLOPT_PROTOCOLS, CURLPROTO_HTTP | CURLPROTO_HTTPS);
932 CURL_EASY_SETOPT (curl, CURLOPT_MAXREDIRS, 4);
933 /* no need to abort if the above failed */
934 CURL_EASY_SETOPT (curl, CURLOPT_URL, current_url);
940 CURL_EASY_SETOPT (curl, CURLOPT_FAILONERROR, 1);
942 CURL_EASY_SETOPT (curl, CURLOPT_VERBOSE, 1);
944 CURL_EASY_SETOPT (curl, CURLOPT_BUFFERSIZE, GNUNET_SERVER_MAX_MESSAGE_SIZE);
945 if (0 == strncmp (current_url, "http", 4))
946 CURL_EASY_SETOPT (curl, CURLOPT_USERAGENT, "GNUnet");
947 CURL_EASY_SETOPT (curl, CURLOPT_CONNECTTIMEOUT, 60L);
948 CURL_EASY_SETOPT (curl, CURLOPT_TIMEOUT, 60L);
950 /* this should no longer be needed; we're now single-threaded! */
951 CURL_EASY_SETOPT (curl, CURLOPT_NOSIGNAL, 1);
953 multi = curl_multi_init ();
960 mret = curl_multi_add_handle (multi, curl);
961 if (mret != CURLM_OK)
963 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
964 "curl_multi_add_handle", __FILE__, __LINE__,
965 curl_multi_strerror (mret));
966 mret = curl_multi_cleanup (multi);
967 if (mret != CURLM_OK)
968 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
969 "curl_multi_cleanup", __FILE__, __LINE__,
970 curl_multi_strerror (mret));
975 end_time = GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_MINUTES);
981 task_download_dispatcher (void *cls,
982 const struct GNUNET_SCHEDULER_TaskContext *tc)
984 ti_download_dispatcher_task = GNUNET_SCHEDULER_NO_TASK;
985 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
987 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download is initiated...\n");
988 if (GNUNET_NO == stat_download_in_progress)
990 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download can start immediately...\n");
991 download_hostlist ();
995 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
996 "Download in progess, have to wait...\n");
997 ti_download_dispatcher_task =
998 GNUNET_SCHEDULER_add_delayed (WAITING_INTERVALL,
999 &task_download_dispatcher, NULL);
1005 * Task that checks if we should try to download a hostlist.
1006 * If so, we initiate the download, otherwise we schedule
1007 * this task again for a later time.
1010 task_check (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1013 struct GNUNET_TIME_Relative delay;
1015 ti_check_download = GNUNET_SCHEDULER_NO_TASK;
1016 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1020 curl_global_cleanup ();
1021 return; /* in shutdown */
1023 if ( (stat_connection_count < MIN_CONNECTIONS) &&
1024 (GNUNET_SCHEDULER_NO_TASK == ti_download_dispatcher_task) )
1025 ti_download_dispatcher_task =
1026 GNUNET_SCHEDULER_add_now (&task_download_dispatcher, NULL);
1028 delay = hostlist_delay;
1029 if (0 == hostlist_delay.rel_value_us)
1030 hostlist_delay = GNUNET_TIME_UNIT_SECONDS;
1032 hostlist_delay = GNUNET_TIME_relative_multiply (hostlist_delay, 2);
1033 if (hostlist_delay.rel_value_us >
1034 GNUNET_TIME_UNIT_HOURS.rel_value_us * (1 + stat_connection_count))
1036 GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS,
1037 (1 + stat_connection_count));
1038 GNUNET_STATISTICS_set (stats,
1040 ("# milliseconds between hostlist downloads"),
1041 hostlist_delay.rel_value_us / 1000LL,
1045 delay = GNUNET_TIME_UNIT_ZERO;
1048 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1049 _("Have %u/%u connections. Will consider downloading hostlist in %s\n"),
1050 stat_connection_count, MIN_CONNECTIONS,
1051 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1052 ti_check_download = GNUNET_SCHEDULER_add_delayed (delay, &task_check, NULL);
1057 * This tasks sets hostlist testing to allowed after intervall between to testings is reached
1059 * @param cls closure
1060 * @param tc TaskContext
1063 task_testing_intervall_reset (void *cls,
1064 const struct GNUNET_SCHEDULER_TaskContext *tc)
1066 ti_testing_intervall_task = GNUNET_SCHEDULER_NO_TASK;
1067 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1069 stat_testing_allowed = GNUNET_OK;
1070 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1071 "Testing new hostlist advertisements is allowed again\n");
1076 * Task that writes hostlist entries to a file on a regular base
1078 * @param cls closure
1079 * @param tc TaskContext
1082 task_hostlist_saving (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1084 ti_saving_task = GNUNET_SCHEDULER_NO_TASK;
1085 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1087 save_hostlist_file (GNUNET_NO);
1089 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1090 "Hostlists will be saved to file again in %s\n",
1091 GNUNET_STRINGS_relative_time_to_string(SAVING_INTERVALL, GNUNET_YES));
1093 GNUNET_SCHEDULER_add_delayed (SAVING_INTERVALL, &task_hostlist_saving,
1099 * Method called whenever a given peer connects.
1101 * @param cls closure
1102 * @param peer peer identity this notification is about
1105 handler_connect (void *cls, const struct GNUNET_PeerIdentity *peer)
1107 GNUNET_assert (stat_connection_count < UINT_MAX);
1108 stat_connection_count++;
1109 GNUNET_STATISTICS_update (stats, gettext_noop ("# active connections"), 1,
1115 * Method called whenever a given peer disconnects.
1117 * @param cls closure
1118 * @param peer peer identity this notification is about
1121 handler_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
1123 GNUNET_assert (stat_connection_count > 0);
1124 stat_connection_count--;
1125 GNUNET_STATISTICS_update (stats, gettext_noop ("# active connections"), -1,
1131 * Method called whenever an advertisement message arrives.
1133 * @param cls closure (always NULL)
1134 * @param peer the peer sending the message
1135 * @param message the actual message
1136 * @return #GNUNET_OK to keep the connection open,
1137 * #GNUNET_SYSERR to close it (signal serious error)
1140 handler_advertisement (void *cls, const struct GNUNET_PeerIdentity *peer,
1141 const struct GNUNET_MessageHeader *message)
1145 const struct GNUNET_MessageHeader *incoming;
1147 struct Hostlist *hostlist;
1149 GNUNET_assert (ntohs (message->type) ==
1150 GNUNET_MESSAGE_TYPE_HOSTLIST_ADVERTISEMENT);
1151 size = ntohs (message->size);
1152 if (size <= sizeof (struct GNUNET_MessageHeader))
1154 GNUNET_break_op (0);
1155 return GNUNET_SYSERR;
1157 incoming = (const struct GNUNET_MessageHeader *) message;
1158 uri = (const char *) &incoming[1];
1159 uri_size = size - sizeof (struct GNUNET_MessageHeader);
1160 if (uri[uri_size - 1] != '\0')
1162 GNUNET_break_op (0);
1163 return GNUNET_SYSERR;
1165 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1166 "Hostlist client recieved advertisement from `%s' containing URI `%s'\n",
1167 GNUNET_i2s (peer), uri);
1168 if (GNUNET_NO != linked_list_contains (uri))
1170 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "URI `%s' is already known\n", uri);
1174 if (GNUNET_NO == stat_testing_allowed)
1176 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1177 "Currently not accepting new advertisements: interval between to advertisements is not reached\n");
1178 return GNUNET_SYSERR;
1180 if (GNUNET_YES == stat_testing_hostlist)
1182 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1183 "Currently not accepting new advertisements: we are already testing a hostlist\n");
1184 return GNUNET_SYSERR;
1187 hostlist = GNUNET_malloc (sizeof (struct Hostlist) + uri_size);
1188 hostlist->hostlist_uri = (const char *) &hostlist[1];
1189 memcpy (&hostlist[1], uri, uri_size);
1190 hostlist->time_creation = GNUNET_TIME_absolute_get ();
1191 hostlist->quality = HOSTLIST_INITIAL;
1192 hostlist_to_test = hostlist;
1194 stat_testing_hostlist = GNUNET_YES;
1195 stat_testing_allowed = GNUNET_NO;
1196 ti_testing_intervall_task =
1197 GNUNET_SCHEDULER_add_delayed (TESTING_INTERVAL,
1198 &task_testing_intervall_reset, NULL);
1200 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1201 "Testing new hostlist advertisements is locked for the next %s\n",
1202 GNUNET_STRINGS_relative_time_to_string (TESTING_INTERVAL,
1205 ti_download_dispatcher_task =
1206 GNUNET_SCHEDULER_add_now (&task_download_dispatcher, NULL);
1213 * Continuation called by the statistics code once
1214 * we go the stat. Initiates hostlist download scheduling.
1216 * @param cls closure
1217 * @param success #GNUNET_OK if statistics were
1218 * successfully obtained, #GNUNET_SYSERR if not.
1221 primary_task (void *cls, int success)
1224 GNUNET_assert (stats != NULL);
1225 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1226 "Statistics request done, scheduling hostlist download\n");
1227 ti_check_download = GNUNET_SCHEDULER_add_now (&task_check, NULL);
1232 * We've received the previous delay value from statistics. Remember it.
1234 * @param cls NULL, unused
1235 * @param subsystem should be "hostlist", unused
1236 * @param name will be "milliseconds between hostlist downloads", unused
1237 * @param value previous delay value, in milliseconds (!)
1238 * @param is_persistent unused, will be GNUNET_YES
1241 process_stat (void *cls, const char *subsystem, const char *name,
1242 uint64_t value, int is_persistent)
1244 hostlist_delay.rel_value_us = value * 1000LL;
1245 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1246 "Initial time between hostlist downloads is %s\n",
1247 GNUNET_STRINGS_relative_time_to_string (hostlist_delay, GNUNET_YES));
1253 * Method to load persistent hostlist file during hostlist client startup
1256 load_hostlist_file ()
1261 struct Hostlist *hostlist;
1262 uint32_t times_used;
1263 uint32_t hellos_returned;
1271 GNUNET_CONFIGURATION_get_value_filename (cfg, "HOSTLIST", "HOSTLISTFILE",
1274 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_WARNING,
1275 "hostlist", "HOSTLISTFILE");
1279 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1280 _("Loading saved hostlist entries from file `%s' \n"),
1282 if (GNUNET_NO == GNUNET_DISK_file_test (filename))
1284 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1285 _("Hostlist file `%s' does not exist\n"), filename);
1286 GNUNET_free (filename);
1290 struct GNUNET_BIO_ReadHandle *rh = GNUNET_BIO_read_open (filename);
1294 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1296 ("Could not open file `%s' for reading to load hostlists: %s\n"),
1297 filename, STRERROR (errno));
1298 GNUNET_free (filename);
1303 while ((GNUNET_OK == GNUNET_BIO_read_string (rh, "url", &uri, MAX_URL_LEN)) &&
1304 (NULL != uri) && (GNUNET_OK == GNUNET_BIO_read_int32 (rh, ×_used))
1305 && (GNUNET_OK == GNUNET_BIO_read_int64 (rh, &quality)) &&
1306 (GNUNET_OK == GNUNET_BIO_read_int64 (rh, &last_used)) &&
1307 (GNUNET_OK == GNUNET_BIO_read_int64 (rh, &created)) &&
1308 (GNUNET_OK == GNUNET_BIO_read_int32 (rh, &hellos_returned)))
1310 hostlist = GNUNET_malloc (sizeof (struct Hostlist) + strlen (uri) + 1);
1311 hostlist->hello_count = hellos_returned;
1312 hostlist->hostlist_uri = (const char *) &hostlist[1];
1313 memcpy (&hostlist[1], uri, strlen (uri) + 1);
1314 hostlist->quality = quality;
1315 hostlist->time_creation.abs_value_us = created;
1316 hostlist->time_last_usage.abs_value_us = last_used;
1317 GNUNET_CONTAINER_DLL_insert (linked_list_head, linked_list_tail, hostlist);
1319 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1320 "Added hostlist entry eith URI `%s' \n",
1321 hostlist->hostlist_uri);
1325 if (counter >= MAX_NUMBER_HOSTLISTS)
1329 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("%u hostlist URIs loaded from file\n"),
1331 GNUNET_STATISTICS_set (stats, gettext_noop ("# hostlist URIs read from file"),
1332 counter, GNUNET_YES);
1333 GNUNET_STATISTICS_set (stats, gettext_noop ("# advertised hostlist URIs"),
1334 linked_list_size, GNUNET_NO);
1336 GNUNET_free_non_null (uri);
1338 (void) GNUNET_BIO_read_close (rh, &emsg);
1341 GNUNET_free (filename);
1346 * Method to save persistent hostlist file during hostlist client shutdown
1347 * @param shutdown set if called because of shutdown, entries in linked list will be destroyed
1350 save_hostlist_file (int shutdown)
1353 struct Hostlist *pos;
1354 struct GNUNET_BIO_WriteHandle *wh;
1359 GNUNET_CONFIGURATION_get_value_filename (cfg, "HOSTLIST", "HOSTLISTFILE",
1362 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_WARNING,
1363 "hostlist", "HOSTLISTFILE");
1366 if (GNUNET_SYSERR == GNUNET_DISK_directory_create_for_file (filename))
1368 GNUNET_free (filename);
1371 wh = GNUNET_BIO_write_open (filename);
1374 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1376 ("Could not open file `%s' for writing to save hostlists: %s\n"),
1377 filename, STRERROR (errno));
1378 GNUNET_free (filename);
1381 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Writing %u hostlist URIs to `%s'\n"),
1382 linked_list_size, filename);
1383 /* add code to write hostlists to file using bio */
1386 while (NULL != (pos = linked_list_head))
1388 if (GNUNET_YES == shutdown)
1390 GNUNET_CONTAINER_DLL_remove (linked_list_head, linked_list_tail, pos);
1393 if (GNUNET_YES == ok)
1395 if ((GNUNET_OK != GNUNET_BIO_write_string (wh, pos->hostlist_uri)) ||
1396 (GNUNET_OK != GNUNET_BIO_write_int32 (wh, pos->times_used)) ||
1397 (GNUNET_OK != GNUNET_BIO_write_int64 (wh, pos->quality)) ||
1399 GNUNET_BIO_write_int64 (wh, pos->time_last_usage.abs_value_us)) ||
1401 GNUNET_BIO_write_int64 (wh, pos->time_creation.abs_value_us)) ||
1402 (GNUNET_OK != GNUNET_BIO_write_int32 (wh, pos->hello_count)))
1404 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1405 _("Error writing hostlist URIs to file `%s'\n"), filename);
1410 if (GNUNET_YES == shutdown)
1413 if (counter >= MAX_NUMBER_HOSTLISTS)
1416 GNUNET_STATISTICS_set (stats,
1417 gettext_noop ("# hostlist URIs written to file"),
1418 counter, GNUNET_YES);
1420 if (GNUNET_OK != GNUNET_BIO_write_close (wh))
1421 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1422 _("Error writing hostlist URIs to file `%s'\n"), filename);
1423 GNUNET_free (filename);
1428 * Start downloading hostlists from hostlist servers as necessary.
1431 GNUNET_HOSTLIST_client_start (const struct GNUNET_CONFIGURATION_Handle *c,
1432 struct GNUNET_STATISTICS_Handle *st,
1433 GNUNET_CORE_ConnectEventHandler *ch,
1434 GNUNET_CORE_DisconnectEventHandler *dh,
1435 GNUNET_CORE_MessageCallback *msgh, int learn)
1440 GNUNET_assert (NULL != st);
1441 if (0 != curl_global_init (CURL_GLOBAL_WIN32))
1444 return GNUNET_SYSERR;
1446 transport = GNUNET_TRANSPORT_connect (c, NULL, NULL, NULL, NULL, NULL);
1447 if (NULL == transport)
1449 curl_global_cleanup ();
1450 return GNUNET_SYSERR;
1455 GNUNET_CONFIGURATION_get_value_string (cfg, "HOSTLIST", "HTTP-PROXY",
1458 stat_learning = learn;
1459 *ch = &handler_connect;
1460 *dh = &handler_disconnect;
1461 linked_list_head = NULL;
1462 linked_list_tail = NULL;
1463 stat_use_bootstrap = GNUNET_YES;
1464 stat_testing_hostlist = GNUNET_NO;
1465 stat_testing_allowed = GNUNET_YES;
1467 if (GNUNET_YES == stat_learning)
1469 *msgh = &handler_advertisement;
1470 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1471 _("Learning is enabled on this peer\n"));
1472 load_hostlist_file ();
1473 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1474 "Hostlists will be saved to file again in %s\n",
1475 GNUNET_STRINGS_relative_time_to_string (SAVING_INTERVALL, GNUNET_YES));
1477 GNUNET_SCHEDULER_add_delayed (SAVING_INTERVALL, &task_hostlist_saving,
1482 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1483 _("Learning is not enabled on this peer\n"));
1486 GNUNET_CONFIGURATION_get_value_filename (cfg, "HOSTLIST",
1487 "HOSTLISTFILE", &filename))
1489 if (GNUNET_YES == GNUNET_DISK_file_test (filename))
1491 result = remove (filename);
1493 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1495 ("Since learning is not enabled on this peer, hostlist file `%s' was removed\n"),
1498 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1499 _("Hostlist file `%s' could not be removed\n"), filename);
1502 GNUNET_free (filename);
1504 sget = GNUNET_STATISTICS_get (stats, "hostlist",
1506 ("# milliseconds between hostlist downloads"),
1507 GNUNET_TIME_UNIT_MINUTES, &primary_task, &process_stat,
1514 * Stop downloading hostlists from hostlist servers as necessary.
1517 GNUNET_HOSTLIST_client_stop ()
1519 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Hostlist client shutdown\n");
1522 GNUNET_STATISTICS_get_cancel (sget);
1526 if (GNUNET_YES == stat_learning)
1527 save_hostlist_file (GNUNET_YES);
1528 if (ti_saving_task != GNUNET_SCHEDULER_NO_TASK)
1530 GNUNET_SCHEDULER_cancel (ti_saving_task);
1531 ti_saving_task = GNUNET_SCHEDULER_NO_TASK;
1534 if (ti_download_dispatcher_task != GNUNET_SCHEDULER_NO_TASK)
1536 GNUNET_SCHEDULER_cancel (ti_download_dispatcher_task);
1537 ti_download_dispatcher_task = GNUNET_SCHEDULER_NO_TASK;
1539 if (ti_testing_intervall_task != GNUNET_SCHEDULER_NO_TASK)
1541 GNUNET_SCHEDULER_cancel (ti_testing_intervall_task);
1542 ti_testing_intervall_task = GNUNET_SCHEDULER_NO_TASK;
1544 if (ti_download != GNUNET_SCHEDULER_NO_TASK)
1546 GNUNET_SCHEDULER_cancel (ti_download);
1547 ti_download = GNUNET_SCHEDULER_NO_TASK;
1549 if (ti_check_download != GNUNET_SCHEDULER_NO_TASK)
1551 GNUNET_SCHEDULER_cancel (ti_check_download);
1552 ti_check_download = GNUNET_SCHEDULER_NO_TASK;
1553 curl_global_cleanup ();
1555 if (transport != NULL)
1557 GNUNET_TRANSPORT_disconnect (transport);
1560 GNUNET_free_non_null (proxy);
1565 /* end of hostlist-client.c */