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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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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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_common.h"
37 #include "gnunet_bio_lib.h"
41 * Number of connections that we must have to NOT download
44 #define MIN_CONNECTIONS 4
47 * Interval between two advertised hostlist tests
49 #define TESTING_INTERVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
52 * A single hostlist obtained by hostlist advertisements
57 * previous entry, used to manage entries in a double linked list
59 struct Hostlist *prev;
62 * next entry, used to manage entries in a double linked list
64 struct Hostlist *next;
67 * URI where hostlist can be obtained
69 const char *hostlist_uri;
72 * Value describing the quality of the hostlist, the bigger the better but (should) never < 0
73 * used for deciding which hostlist is replaced if MAX_NUMBER_HOSTLISTS in data structure is reached
74 * intial value = HOSTLIST_INITIAL
75 * increased every successful download by HOSTLIST_SUCCESSFULL_DOWNLOAD
76 * increased every successful download by number of obtained HELLO messages
77 * decreased every failed download by HOSTLIST_SUCCESSFULL_DOWNLOAD
82 * Time the hostlist advertisement was recieved and the entry was created
84 struct GNUNET_TIME_Absolute time_creation;
87 * Last time the hostlist was obtained
89 struct GNUNET_TIME_Absolute time_last_usage;
92 * Number of HELLO messages obtained during last download
97 * Number of times the hostlist was successfully obtained
107 static const struct GNUNET_CONFIGURATION_Handle *cfg;
112 static struct GNUNET_STATISTICS_Handle *stats;
117 static struct GNUNET_TRANSPORT_Handle *transport;
120 * Proxy that we are using (can be NULL).
125 * Number of bytes valid in 'download_buffer'.
127 static size_t download_pos;
130 * Current URL that we are using.
132 static char *current_url;
135 * Current CURL handle.
140 * Current multi-CURL handle.
145 * How many bytes did we download from the current hostlist URL?
147 static uint32_t stat_bytes_downloaded;
150 * Amount of time we wait between hostlist downloads.
152 static struct GNUNET_TIME_Relative hostlist_delay;
155 * ID of the task, checking if hostlist download should take plate
157 static GNUNET_SCHEDULER_TaskIdentifier ti_check_download;
160 * ID of the task downloading the hostlist
162 static GNUNET_SCHEDULER_TaskIdentifier ti_download;
165 * ID of the task saving the hostlsit in a regular intervall
167 static GNUNET_SCHEDULER_TaskIdentifier ti_saving_task;
170 * ID of the task called to initiate a download
172 static GNUNET_SCHEDULER_TaskIdentifier ti_download_dispatcher_task;
175 * ID of the task controlling the locking between two hostlist tests
177 static GNUNET_SCHEDULER_TaskIdentifier ti_testing_intervall_task;
180 * At what time MUST the current hostlist request be done?
182 static struct GNUNET_TIME_Absolute end_time;
185 * Head of the linked list used to store hostlists
187 static struct Hostlist *linked_list_head;
190 * Tail of the linked list used to store hostlists
192 static struct Hostlist *linked_list_tail;
195 * Current hostlist used for downloading
197 static struct Hostlist *current_hostlist;
200 * Size of the linke list used to store hostlists
202 static unsigned int linked_list_size;
205 * Head of the linked list used to store hostlists
207 static struct Hostlist *hostlist_to_test;
210 * Handle for our statistics GET operation.
212 static struct GNUNET_STATISTICS_GetHandle *sget;
215 * Set to GNUNET_YES if the current URL had some problems.
217 static int stat_bogus_url;
220 * Value controlling if a hostlist is tested at the moment
222 static int stat_testing_hostlist;
225 * Value controlling if a hostlist testing is allowed at the moment
227 static int stat_testing_allowed;
230 * Value controlling if a hostlist download is running at the moment
232 static int stat_download_in_progress;
235 * Value saying if a preconfigured bootstrap server is used
237 static unsigned int stat_use_bootstrap;
240 * Set if we are allowed to learn new hostlists and use them
242 static int stat_learning;
245 * Value saying if hostlist download was successful
247 static unsigned int stat_download_successful;
250 * Value saying how many valid HELLO messages were obtained during download
252 static unsigned int stat_hellos_obtained;
255 * Number of active connections (according to core service).
257 static unsigned int stat_connection_count;
261 * Process downloaded bits by calling callback on each HELLO.
263 * @param ptr buffer with downloaded data
264 * @param size size of a record
265 * @param nmemb number of records downloaded
267 * @return number of bytes that were processed (always size*nmemb)
270 callback_download (void *ptr, size_t size, size_t nmemb, void *ctx)
272 static char download_buffer[GNUNET_SERVER_MAX_MESSAGE_SIZE - 1];
273 const char *cbuf = ptr;
274 const struct GNUNET_MessageHeader *msg;
280 total = size * nmemb;
281 stat_bytes_downloaded += total;
282 if ((total == 0) || (stat_bogus_url))
284 return total; /* ok, no data or bogus data */
287 GNUNET_STATISTICS_update (stats,
289 ("# bytes downloaded from hostlist servers"),
290 (int64_t) total, GNUNET_NO);
292 while ((left > 0) || (download_pos > 0))
294 cpy = GNUNET_MIN (left, GNUNET_SERVER_MAX_MESSAGE_SIZE - 1 - download_pos);
295 memcpy (&download_buffer[download_pos], cbuf, cpy);
299 if (download_pos < sizeof (struct GNUNET_MessageHeader))
301 GNUNET_assert (left == 0);
304 msg = (const struct GNUNET_MessageHeader *) download_buffer;
305 msize = ntohs (msg->size);
306 if (msize < sizeof (struct GNUNET_MessageHeader))
308 GNUNET_STATISTICS_update (stats,
310 ("# invalid HELLOs downloaded from hostlist servers"),
312 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
313 _("Invalid `%s' message received from hostlist at `%s'\n"),
314 "HELLO", current_url);
315 stat_hellos_obtained++;
319 if (download_pos < msize)
321 GNUNET_assert (left == 0);
324 if (GNUNET_HELLO_size ((const struct GNUNET_HELLO_Message *) msg) == msize)
326 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
327 "Received valid `%s' message from hostlist server.\n",
329 GNUNET_STATISTICS_update (stats,
331 ("# valid HELLOs downloaded from hostlist servers"),
333 stat_hellos_obtained++;
334 GNUNET_TRANSPORT_offer_hello (transport, msg, NULL, NULL);
338 GNUNET_STATISTICS_update (stats,
340 ("# invalid HELLOs downloaded from hostlist servers"),
342 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
343 _("Invalid `%s' message received from hostlist at `%s'\n"),
344 "HELLO", current_url);
345 stat_bogus_url = GNUNET_YES;
346 stat_hellos_obtained++;
349 memmove (download_buffer, &download_buffer[msize], download_pos - msize);
350 download_pos -= msize;
357 * Obtain a hostlist URL that we should use.
359 * @return NULL if there is no URL available
362 get_bootstrap_server ()
370 GNUNET_CONFIGURATION_get_value_string (cfg, "HOSTLIST", "SERVERS",
373 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
375 ("No `%s' specified in `%s' configuration, will not bootstrap.\n"),
376 "SERVERS", "HOSTLIST");
381 if (strlen (servers) > 0)
384 pos = strlen (servers) - 1;
387 if (servers[pos] == ' ')
394 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
396 ("No `%s' specified in `%s' configuration, will not bootstrap.\n"),
397 "SERVERS", "HOSTLIST");
398 GNUNET_free (servers);
402 urls = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, urls) + 1;
403 pos = strlen (servers) - 1;
406 if (servers[pos] == ' ')
418 ret = GNUNET_strdup (&servers[pos]);
419 GNUNET_free (servers);
424 * Method deciding if a preconfigured or advertisied hostlist is used on a 50:50 ratio
425 * @return uri to use, NULL if there is no URL available
431 unsigned int counter;
432 struct Hostlist *pos;
434 if (GNUNET_NO == stat_learning)
436 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
437 "Using preconfigured bootstrap server\n");
438 current_hostlist = NULL;
439 return get_bootstrap_server ();
442 if ((GNUNET_YES == stat_testing_hostlist) && (NULL != hostlist_to_test))
444 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
445 "Testing new advertised hostlist if it is obtainable\n");
446 current_hostlist = hostlist_to_test;
447 return GNUNET_strdup (hostlist_to_test->hostlist_uri);
450 if ((GNUNET_YES == stat_use_bootstrap) || (linked_list_size == 0))
452 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
453 "Using preconfigured bootstrap server\n");
454 current_hostlist = NULL;
455 return get_bootstrap_server ();
458 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, linked_list_size);
460 pos = linked_list_head;
461 while (counter < index)
466 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Using learned hostlist `%s'\n",
468 current_hostlist = pos;
469 return GNUNET_strdup (pos->hostlist_uri);
473 #define CURL_EASY_SETOPT(c, a, b) do { ret = curl_easy_setopt(c, a, b); if (ret != CURLE_OK) GNUNET_log(GNUNET_ERROR_TYPE_WARNING, _("%s failed at %s:%d: `%s'\n"), "curl_easy_setopt", __FILE__, __LINE__, curl_easy_strerror(ret)); } while (0)
477 * Method to save hostlist to a file during hostlist client shutdown
478 * @param shutdown set if called because of shutdown, entries in linked list will be destroyed
481 save_hostlist_file (int shutdown);
485 * add val2 to val1 with overflow check
486 * @param val1 value 1
487 * @param val2 value 2
491 checked_add (uint64_t val1, uint64_t val2)
493 static uint64_t temp;
494 static uint64_t maxv;
507 * Subtract val2 from val1 with underflow check
508 * @param val1 value 1
509 * @param val2 value 2
513 checked_sub (uint64_t val1, uint64_t val2)
518 return (val1 - val2);
522 * Method to check if a URI is in hostlist linked list
523 * @param uri uri to check
524 * @return GNUNET_YES if existing in linked list, GNUNET_NO if not
527 linked_list_contains (const char *uri)
529 struct Hostlist *pos;
531 pos = linked_list_head;
534 if (0 == strcmp (pos->hostlist_uri, uri))
543 * Method returning the hostlist element with the lowest quality in the datastore
544 * @return hostlist with lowest quality
546 static struct Hostlist *
547 linked_list_get_lowest_quality ()
549 struct Hostlist *pos;
550 struct Hostlist *lowest;
552 if (linked_list_size == 0)
554 lowest = linked_list_head;
555 pos = linked_list_head->next;
558 if (pos->quality < lowest->quality)
567 * Method to insert a hostlist into the datastore. If datastore
568 * contains maximum number of elements, the elements with lowest
569 * quality is dismissed
574 struct Hostlist *lowest_quality;
576 if (MAX_NUMBER_HOSTLISTS <= linked_list_size)
578 /* No free entries available, replace existing entry */
579 lowest_quality = linked_list_get_lowest_quality ();
580 GNUNET_assert (lowest_quality != NULL);
581 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
582 "Removing hostlist with URI `%s' which has the worst quality of all (%llu)\n",
583 lowest_quality->hostlist_uri,
584 (unsigned long long) lowest_quality->quality);
585 GNUNET_CONTAINER_DLL_remove (linked_list_head, linked_list_tail,
588 GNUNET_free (lowest_quality);
590 GNUNET_CONTAINER_DLL_insert (linked_list_head, linked_list_tail,
593 GNUNET_STATISTICS_set (stats, gettext_noop ("# advertised hostlist URIs"),
594 linked_list_size, GNUNET_NO);
595 stat_testing_hostlist = GNUNET_NO;
600 * Method updating hostlist statistics
607 if (((stat_use_bootstrap == GNUNET_NO) && (NULL != current_hostlist)) ||
608 ((stat_testing_hostlist == GNUNET_YES) && (NULL != current_hostlist)))
610 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
611 "Updating hostlist statics for URI `%s'\n",
612 current_hostlist->hostlist_uri);
613 current_hostlist->hello_count = stat_hellos_obtained;
614 current_hostlist->time_last_usage = GNUNET_TIME_absolute_get ();
615 current_hostlist->quality =
616 checked_add (current_hostlist->quality,
617 (stat_hellos_obtained * HOSTLIST_SUCCESSFUL_HELLO));
618 if (GNUNET_YES == stat_download_successful)
620 current_hostlist->times_used++;
621 current_hostlist->quality =
622 checked_add (current_hostlist->quality, HOSTLIST_SUCCESSFUL_DOWNLOAD);
623 GNUNET_asprintf (&stat, gettext_noop ("# advertised URI `%s' downloaded"),
624 current_hostlist->hostlist_uri);
626 GNUNET_STATISTICS_update (stats, stat, 1, GNUNET_YES);
630 current_hostlist->quality =
631 checked_sub (current_hostlist->quality, HOSTLIST_FAILED_DOWNLOAD);
633 current_hostlist = NULL;
634 /* Alternating the usage of preconfigured and learned hostlists */
636 if (stat_testing_hostlist == GNUNET_YES)
639 if (GNUNET_YES == stat_learning)
641 if (stat_use_bootstrap == GNUNET_YES)
642 stat_use_bootstrap = GNUNET_NO;
644 stat_use_bootstrap = GNUNET_YES;
647 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 (GNUNET_TIME_absolute_get_remaining (end_time).rel_value == 0)
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_INFO,
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_MAXREDIRS, 4);
931 /* no need to abort if the above failed */
932 CURL_EASY_SETOPT (curl, CURLOPT_URL, current_url);
938 CURL_EASY_SETOPT (curl, CURLOPT_FAILONERROR, 1);
940 CURL_EASY_SETOPT (curl, CURLOPT_VERBOSE, 1);
942 CURL_EASY_SETOPT (curl, CURLOPT_BUFFERSIZE, GNUNET_SERVER_MAX_MESSAGE_SIZE);
943 if (0 == strncmp (current_url, "http", 4))
944 CURL_EASY_SETOPT (curl, CURLOPT_USERAGENT, "GNUnet");
945 CURL_EASY_SETOPT (curl, CURLOPT_CONNECTTIMEOUT, 60L);
946 CURL_EASY_SETOPT (curl, CURLOPT_TIMEOUT, 60L);
948 /* this should no longer be needed; we're now single-threaded! */
949 CURL_EASY_SETOPT (curl, CURLOPT_NOSIGNAL, 1);
951 multi = curl_multi_init ();
958 mret = curl_multi_add_handle (multi, curl);
959 if (mret != CURLM_OK)
961 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
962 "curl_multi_add_handle", __FILE__, __LINE__,
963 curl_multi_strerror (mret));
964 mret = curl_multi_cleanup (multi);
965 if (mret != CURLM_OK)
966 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
967 "curl_multi_cleanup", __FILE__, __LINE__,
968 curl_multi_strerror (mret));
973 end_time = GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_MINUTES);
979 task_download_dispatcher (void *cls,
980 const struct GNUNET_SCHEDULER_TaskContext *tc)
982 ti_download_dispatcher_task = GNUNET_SCHEDULER_NO_TASK;
983 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
985 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download is initiated...\n");
986 if (GNUNET_NO == stat_download_in_progress)
988 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download can start immediately...\n");
989 download_hostlist ();
993 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
994 "Download in progess, have to wait...\n");
995 ti_download_dispatcher_task =
996 GNUNET_SCHEDULER_add_delayed (WAITING_INTERVALL,
997 &task_download_dispatcher, NULL);
1002 * Task that checks if we should try to download a hostlist.
1003 * If so, we initiate the download, otherwise we schedule
1004 * this task again for a later time.
1007 task_check (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1010 struct GNUNET_TIME_Relative delay;
1012 ti_check_download = GNUNET_SCHEDULER_NO_TASK;
1013 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1017 curl_global_cleanup ();
1018 return; /* in shutdown */
1020 if ( (stat_connection_count < MIN_CONNECTIONS) &&
1021 (GNUNET_SCHEDULER_NO_TASK == ti_download_dispatcher_task) )
1022 ti_download_dispatcher_task =
1023 GNUNET_SCHEDULER_add_now (&task_download_dispatcher, NULL);
1025 delay = hostlist_delay;
1026 if (hostlist_delay.rel_value == 0)
1027 hostlist_delay = GNUNET_TIME_UNIT_SECONDS;
1029 hostlist_delay = GNUNET_TIME_relative_multiply (hostlist_delay, 2);
1030 if (hostlist_delay.rel_value >
1031 GNUNET_TIME_UNIT_HOURS.rel_value * (1 + stat_connection_count))
1033 GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS,
1034 (1 + stat_connection_count));
1035 GNUNET_STATISTICS_set (stats,
1037 ("# milliseconds between hostlist downloads"),
1038 hostlist_delay.rel_value, GNUNET_YES);
1041 delay = GNUNET_TIME_UNIT_ZERO;
1044 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1046 ("Have %u/%u connections. Will consider downloading hostlist in %llums\n"),
1047 stat_connection_count, MIN_CONNECTIONS,
1048 (unsigned long long) delay.rel_value);
1049 ti_check_download = GNUNET_SCHEDULER_add_delayed (delay, &task_check, NULL);
1054 * This tasks sets hostlist testing to allowed after intervall between to testings is reached
1056 * @param cls closure
1057 * @param tc TaskContext
1060 task_testing_intervall_reset (void *cls,
1061 const struct GNUNET_SCHEDULER_TaskContext *tc)
1063 ti_testing_intervall_task = GNUNET_SCHEDULER_NO_TASK;
1064 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1066 stat_testing_allowed = GNUNET_OK;
1067 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1068 "Testing new hostlist advertisements is allowed again\n");
1073 * Task that writes hostlist entries to a file on a regular base
1075 * @param cls closure
1076 * @param tc TaskContext
1079 task_hostlist_saving (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1081 ti_saving_task = GNUNET_SCHEDULER_NO_TASK;
1082 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1084 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Scheduled saving of hostlists\n"));
1085 save_hostlist_file (GNUNET_NO);
1087 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1088 _("Hostlists will be saved to file again in %llums\n"),
1089 (unsigned long long) SAVING_INTERVALL.rel_value);
1091 GNUNET_SCHEDULER_add_delayed (SAVING_INTERVALL, &task_hostlist_saving,
1097 * Method called whenever a given peer connects.
1099 * @param cls closure
1100 * @param peer peer identity this notification is about
1101 * @param atsi performance data
1102 * @param atsi_count number of records in 'atsi'
1105 handler_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
1106 const struct GNUNET_ATS_Information *atsi,
1107 unsigned int atsi_count)
1109 GNUNET_assert (stat_connection_count < UINT_MAX);
1110 stat_connection_count++;
1111 GNUNET_STATISTICS_update (stats, gettext_noop ("# active connections"), 1,
1117 * Method called whenever a given peer disconnects.
1119 * @param cls closure
1120 * @param peer peer identity this notification is about
1123 handler_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
1125 GNUNET_assert (stat_connection_count > 0);
1126 stat_connection_count--;
1127 GNUNET_STATISTICS_update (stats, gettext_noop ("# active connections"), -1,
1133 * Method called whenever an advertisement message arrives.
1135 * @param cls closure (always NULL)
1136 * @param peer the peer sending the message
1137 * @param message the actual message
1138 * @param atsi performance data
1139 * @param atsi_count number of records in 'atsi'
1140 * @return GNUNET_OK to keep the connection open,
1141 * GNUNET_SYSERR to close it (signal serious error)
1144 handler_advertisement (void *cls, const struct GNUNET_PeerIdentity *peer,
1145 const struct GNUNET_MessageHeader *message,
1146 const struct GNUNET_ATS_Information *atsi,
1147 unsigned int atsi_count)
1151 const struct GNUNET_MessageHeader *incoming;
1153 struct Hostlist *hostlist;
1155 GNUNET_assert (ntohs (message->type) ==
1156 GNUNET_MESSAGE_TYPE_HOSTLIST_ADVERTISEMENT);
1157 size = ntohs (message->size);
1158 if (size <= sizeof (struct GNUNET_MessageHeader))
1160 GNUNET_break_op (0);
1161 return GNUNET_SYSERR;
1163 incoming = (const struct GNUNET_MessageHeader *) message;
1164 uri = (const char *) &incoming[1];
1165 uri_size = size - sizeof (struct GNUNET_MessageHeader);
1166 if (uri[uri_size - 1] != '\0')
1168 GNUNET_break_op (0);
1169 return GNUNET_SYSERR;
1171 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1172 "Hostlist client recieved advertisement from `%s' containing URI `%s'\n",
1173 GNUNET_i2s (peer), uri);
1174 if (GNUNET_NO != linked_list_contains (uri))
1176 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "URI `%s' is already known\n", uri);
1180 if (GNUNET_NO == stat_testing_allowed)
1182 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1183 "Currently not accepting new advertisements: interval between to advertisements is not reached\n");
1184 return GNUNET_SYSERR;
1186 if (GNUNET_YES == stat_testing_hostlist)
1188 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1189 "Currently not accepting new advertisements: we are already testing a hostlist\n");
1190 return GNUNET_SYSERR;
1193 hostlist = GNUNET_malloc (sizeof (struct Hostlist) + uri_size);
1194 hostlist->hostlist_uri = (const char *) &hostlist[1];
1195 memcpy (&hostlist[1], uri, uri_size);
1196 hostlist->time_creation = GNUNET_TIME_absolute_get ();
1197 hostlist->quality = HOSTLIST_INITIAL;
1198 hostlist_to_test = hostlist;
1200 stat_testing_hostlist = GNUNET_YES;
1201 stat_testing_allowed = GNUNET_NO;
1202 ti_testing_intervall_task =
1203 GNUNET_SCHEDULER_add_delayed (TESTING_INTERVAL,
1204 &task_testing_intervall_reset, NULL);
1206 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1207 "Testing new hostlist advertisements is locked for the next %u ms\n",
1208 TESTING_INTERVAL.rel_value);
1210 ti_download_dispatcher_task =
1211 GNUNET_SCHEDULER_add_now (&task_download_dispatcher, NULL);
1219 * Continuation called by the statistics code once
1220 * we go the stat. Initiates hostlist download scheduling.
1222 * @param cls closure
1223 * @param success GNUNET_OK if statistics were
1224 * successfully obtained, GNUNET_SYSERR if not.
1227 primary_task (void *cls, int success)
1230 GNUNET_assert (stats != NULL);
1231 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1232 "Statistics request done, scheduling hostlist download\n");
1233 ti_check_download = GNUNET_SCHEDULER_add_now (&task_check, NULL);
1238 process_stat (void *cls, const char *subsystem, const char *name,
1239 uint64_t value, int is_persistent)
1241 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1242 _("Initial time between hostlist downloads is %llums\n"),
1243 (unsigned long long) value);
1244 hostlist_delay.rel_value = value;
1249 * Method to load persistent hostlist file during hostlist client startup
1252 load_hostlist_file ()
1257 struct Hostlist *hostlist;
1260 uint32_t times_used;
1261 uint32_t hellos_returned;
1268 GNUNET_CONFIGURATION_get_value_filename (cfg, "HOSTLIST", "HOSTLISTFILE",
1271 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1273 ("No `%s' specified in `%s' configuration, cannot load hostlists from file.\n"),
1274 "HOSTLISTFILE", "HOSTLIST");
1278 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1279 _("Loading saved hostlist entries from file `%s' \n"), filename);
1280 if (GNUNET_NO == GNUNET_DISK_file_test (filename))
1282 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1283 _("Hostlist file `%s' is not existing\n"), filename);
1284 GNUNET_free (filename);
1288 struct GNUNET_BIO_ReadHandle *rh = GNUNET_BIO_read_open (filename);
1292 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1294 ("Could not open file `%s' for reading to load hostlists: %s\n"),
1295 filename, STRERROR (errno));
1296 GNUNET_free (filename);
1301 while ((GNUNET_OK == GNUNET_BIO_read_string (rh, "url", &uri, MAX_URL_LEN)) &&
1302 (NULL != uri) && (GNUNET_OK == GNUNET_BIO_read_int32 (rh, ×_used))
1303 && (GNUNET_OK == GNUNET_BIO_read_int64 (rh, &quality)) &&
1304 (GNUNET_OK == GNUNET_BIO_read_int64 (rh, &last_used)) &&
1305 (GNUNET_OK == GNUNET_BIO_read_int64 (rh, &created)) &&
1306 (GNUNET_OK == GNUNET_BIO_read_int32 (rh, &hellos_returned)))
1308 hostlist = GNUNET_malloc (sizeof (struct Hostlist) + strlen (uri) + 1);
1309 hostlist->hello_count = hellos_returned;
1310 hostlist->hostlist_uri = (const char *) &hostlist[1];
1311 memcpy (&hostlist[1], uri, strlen (uri) + 1);
1312 hostlist->quality = quality;
1313 hostlist->time_creation.abs_value = created;
1314 hostlist->time_last_usage.abs_value = last_used;
1315 GNUNET_CONTAINER_DLL_insert (linked_list_head, linked_list_tail, hostlist);
1317 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1318 "Added hostlist entry eith URI `%s' \n",
1319 hostlist->hostlist_uri);
1323 if (counter >= MAX_NUMBER_HOSTLISTS)
1327 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("%u hostlist URIs loaded from file\n"),
1329 GNUNET_STATISTICS_set (stats, gettext_noop ("# hostlist URIs read from file"),
1330 counter, GNUNET_YES);
1331 GNUNET_STATISTICS_set (stats, gettext_noop ("# advertised hostlist URIs"),
1332 linked_list_size, GNUNET_NO);
1334 GNUNET_free_non_null (uri);
1336 (void) GNUNET_BIO_read_close (rh, &emsg);
1339 GNUNET_free (filename);
1344 * Method to save persistent hostlist file during hostlist client shutdown
1345 * @param shutdown set if called because of shutdown, entries in linked list will be destroyed
1348 save_hostlist_file (int shutdown)
1351 struct Hostlist *pos;
1352 struct GNUNET_BIO_WriteHandle *wh;
1357 GNUNET_CONFIGURATION_get_value_filename (cfg, "HOSTLIST", "HOSTLISTFILE",
1360 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1362 ("No `%s' specified in `%s' configuration, cannot save hostlists to file.\n"),
1363 "HOSTLISTFILE", "HOSTLIST");
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)) ||
1401 GNUNET_BIO_write_int64 (wh, pos->time_creation.abs_value)) ||
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);
1427 * Start downloading hostlists from hostlist servers as necessary.
1430 GNUNET_HOSTLIST_client_start (const struct GNUNET_CONFIGURATION_Handle *c,
1431 struct GNUNET_STATISTICS_Handle *st,
1432 GNUNET_CORE_ConnectEventHandler *ch,
1433 GNUNET_CORE_DisconnectEventHandler *dh,
1434 GNUNET_CORE_MessageCallback *msgh, int learn)
1439 GNUNET_assert (NULL != st);
1440 if (0 != curl_global_init (CURL_GLOBAL_WIN32))
1443 return GNUNET_SYSERR;
1445 transport = GNUNET_TRANSPORT_connect (c, NULL, NULL, NULL, NULL, NULL);
1446 if (NULL == transport)
1448 curl_global_cleanup ();
1449 return GNUNET_SYSERR;
1454 GNUNET_CONFIGURATION_get_value_string (cfg, "HOSTLIST", "HTTP-PROXY",
1457 stat_learning = learn;
1458 *ch = &handler_connect;
1459 *dh = &handler_disconnect;
1460 linked_list_head = NULL;
1461 linked_list_tail = NULL;
1462 stat_use_bootstrap = GNUNET_YES;
1463 stat_testing_hostlist = GNUNET_NO;
1464 stat_testing_allowed = GNUNET_YES;
1466 if (GNUNET_YES == stat_learning)
1468 *msgh = &handler_advertisement;
1469 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1470 _("Learning is enabled on this peer\n"));
1471 load_hostlist_file ();
1472 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1473 _("Hostlists will be saved to file again in %llums\n"),
1474 (unsigned long long) SAVING_INTERVALL.rel_value);
1476 GNUNET_SCHEDULER_add_delayed (SAVING_INTERVALL, &task_hostlist_saving,
1481 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1482 _("Learning is not enabled on this peer\n"));
1485 GNUNET_CONFIGURATION_get_value_filename (cfg, "HOSTLIST",
1486 "HOSTLISTFILE", &filename))
1488 if (GNUNET_YES == GNUNET_DISK_file_test (filename))
1490 result = remove (filename);
1492 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1494 ("Since learning is not enabled on this peer, hostlist file `%s' was removed\n"),
1497 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1498 _("Hostlist file `%s' could not be removed\n"), filename);
1501 GNUNET_free (filename);
1503 sget = GNUNET_STATISTICS_get (stats, "hostlist",
1505 ("# milliseconds between hostlist downloads"),
1506 GNUNET_TIME_UNIT_MINUTES, &primary_task, &process_stat,
1513 * Stop downloading hostlists from hostlist servers as necessary.
1516 GNUNET_HOSTLIST_client_stop ()
1518 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Hostlist client shutdown\n");
1521 GNUNET_STATISTICS_get_cancel (sget);
1525 if (GNUNET_YES == stat_learning)
1526 save_hostlist_file (GNUNET_YES);
1527 if (ti_saving_task != GNUNET_SCHEDULER_NO_TASK)
1529 GNUNET_SCHEDULER_cancel (ti_saving_task);
1530 ti_saving_task = GNUNET_SCHEDULER_NO_TASK;
1533 if (ti_download_dispatcher_task != GNUNET_SCHEDULER_NO_TASK)
1535 GNUNET_SCHEDULER_cancel (ti_download_dispatcher_task);
1536 ti_download_dispatcher_task = GNUNET_SCHEDULER_NO_TASK;
1538 if (ti_testing_intervall_task != GNUNET_SCHEDULER_NO_TASK)
1540 GNUNET_SCHEDULER_cancel (ti_testing_intervall_task);
1541 ti_testing_intervall_task = GNUNET_SCHEDULER_NO_TASK;
1543 if (ti_download != GNUNET_SCHEDULER_NO_TASK)
1545 GNUNET_SCHEDULER_cancel (ti_download);
1546 ti_download = GNUNET_SCHEDULER_NO_TASK;
1548 if (ti_check_download != GNUNET_SCHEDULER_NO_TASK)
1550 GNUNET_SCHEDULER_cancel (ti_check_download);
1551 ti_check_download = GNUNET_SCHEDULER_NO_TASK;
1552 curl_global_cleanup ();
1554 if (transport != NULL)
1556 GNUNET_TRANSPORT_disconnect (transport);
1559 GNUNET_free_non_null (proxy);
1564 /* end of hostlist-client.c */