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
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13 General Public License for more details.
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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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"
39 #define DEBUG_HOSTLIST_CLIENT GNUNET_EXTRA_LOGGING
43 * Number of connections that we must have to NOT download
46 #define MIN_CONNECTIONS 4
49 * Interval between two advertised hostlist tests
51 #define TESTING_INTERVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
54 * A single hostlist obtained by hostlist advertisements
59 * previous entry, used to manage entries in a double linked list
61 struct Hostlist *prev;
64 * next entry, used to manage entries in a double linked list
66 struct Hostlist *next;
69 * URI where hostlist can be obtained
71 const char *hostlist_uri;
74 * Value describing the quality of the hostlist, the bigger the better but (should) never < 0
75 * used for deciding which hostlist is replaced if MAX_NUMBER_HOSTLISTS in data structure is reached
76 * intial value = HOSTLIST_INITIAL
77 * increased every successful download by HOSTLIST_SUCCESSFULL_DOWNLOAD
78 * increased every successful download by number of obtained HELLO messages
79 * decreased every failed download by HOSTLIST_SUCCESSFULL_DOWNLOAD
84 * Time the hostlist advertisement was recieved and the entry was created
86 struct GNUNET_TIME_Absolute time_creation;
89 * Last time the hostlist was obtained
91 struct GNUNET_TIME_Absolute time_last_usage;
94 * Number of HELLO messages obtained during last download
99 * Number of times the hostlist was successfully obtained
109 static const struct GNUNET_CONFIGURATION_Handle *cfg;
114 static struct GNUNET_STATISTICS_Handle *stats;
119 static struct GNUNET_TRANSPORT_Handle *transport;
122 * Proxy that we are using (can be NULL).
127 * Number of bytes valid in 'download_buffer'.
129 static size_t download_pos;
132 * Current URL that we are using.
134 static char *current_url;
137 * Current CURL handle.
142 * Current multi-CURL handle.
147 * How many bytes did we download from the current hostlist URL?
149 static uint32_t stat_bytes_downloaded;
152 * Amount of time we wait between hostlist downloads.
154 static struct GNUNET_TIME_Relative hostlist_delay;
157 * ID of the task, checking if hostlist download should take plate
159 static GNUNET_SCHEDULER_TaskIdentifier ti_check_download;
162 * ID of the task downloading the hostlist
164 static GNUNET_SCHEDULER_TaskIdentifier ti_download;
167 * ID of the task saving the hostlsit in a regular intervall
169 static GNUNET_SCHEDULER_TaskIdentifier ti_saving_task;
172 * ID of the task called to initiate a download
174 static GNUNET_SCHEDULER_TaskIdentifier ti_download_dispatcher_task;
177 * ID of the task controlling the locking between two hostlist tests
179 static GNUNET_SCHEDULER_TaskIdentifier ti_testing_intervall_task;
182 * At what time MUST the current hostlist request be done?
184 static struct GNUNET_TIME_Absolute end_time;
187 * Head of the linked list used to store hostlists
189 static struct Hostlist *linked_list_head;
192 * Tail of the linked list used to store hostlists
194 static struct Hostlist *linked_list_tail;
197 * Current hostlist used for downloading
199 static struct Hostlist *current_hostlist;
202 * Size of the linke list used to store hostlists
204 static unsigned int linked_list_size;
207 * Head of the linked list used to store hostlists
209 static struct Hostlist *hostlist_to_test;
212 * Set to GNUNET_YES if the current URL had some problems.
214 static int stat_bogus_url;
217 * Value controlling if a hostlist is tested at the moment
219 static int stat_testing_hostlist;
222 * Value controlling if a hostlist testing is allowed at the moment
224 static int stat_testing_allowed;
227 * Value controlling if a hostlist download is running at the moment
229 static int stat_download_in_progress;
232 * Value saying if a preconfigured bootstrap server is used
234 static unsigned int stat_use_bootstrap;
237 * Set if we are allowed to learn new hostlists and use them
239 static int stat_learning;
242 * Value saying if hostlist download was successful
244 static unsigned int stat_download_successful;
247 * Value saying how many valid HELLO messages were obtained during download
249 static unsigned int stat_hellos_obtained;
252 * Number of active connections (according to core service).
254 static unsigned int stat_connection_count;
258 * Process downloaded bits by calling callback on each HELLO.
260 * @param ptr buffer with downloaded data
261 * @param size size of a record
262 * @param nmemb number of records downloaded
264 * @return number of bytes that were processed (always size*nmemb)
267 callback_download (void *ptr, size_t size, size_t nmemb, void *ctx)
269 static char download_buffer[GNUNET_SERVER_MAX_MESSAGE_SIZE - 1];
270 const char *cbuf = ptr;
271 const struct GNUNET_MessageHeader *msg;
277 total = size * nmemb;
278 stat_bytes_downloaded += total;
279 if ((total == 0) || (stat_bogus_url))
281 return total; /* ok, no data or bogus data */
284 GNUNET_STATISTICS_update (stats,
286 ("# bytes downloaded from hostlist servers"),
287 (int64_t) total, GNUNET_NO);
289 while ((left > 0) || (download_pos > 0))
291 cpy = GNUNET_MIN (left, GNUNET_SERVER_MAX_MESSAGE_SIZE - 1 - download_pos);
292 memcpy (&download_buffer[download_pos], cbuf, cpy);
296 if (download_pos < sizeof (struct GNUNET_MessageHeader))
298 GNUNET_assert (left == 0);
301 msg = (const struct GNUNET_MessageHeader *) download_buffer;
302 msize = ntohs (msg->size);
303 if (msize < sizeof (struct GNUNET_MessageHeader))
305 GNUNET_STATISTICS_update (stats,
307 ("# invalid HELLOs downloaded from hostlist servers"),
309 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
310 _("Invalid `%s' message received from hostlist at `%s'\n"),
311 "HELLO", current_url);
312 stat_hellos_obtained++;
316 if (download_pos < msize)
318 GNUNET_assert (left == 0);
321 if (GNUNET_HELLO_size ((const struct GNUNET_HELLO_Message *) msg) == msize)
323 #if DEBUG_HOSTLIST_CLIENT
324 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
325 "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 (GNUNET_ERROR_TYPE_WARNING,
374 ("No `%s' specified in `%s' configuration, will not bootstrap.\n"),
375 "SERVERS", "HOSTLIST");
380 if (strlen (servers) > 0)
383 pos = strlen (servers) - 1;
386 if (servers[pos] == ' ')
393 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
395 ("No `%s' specified in `%s' configuration, will not bootstrap.\n"),
396 "SERVERS", "HOSTLIST");
397 GNUNET_free (servers);
401 urls = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, urls) + 1;
402 pos = strlen (servers) - 1;
405 if (servers[pos] == ' ')
417 ret = GNUNET_strdup (&servers[pos]);
418 GNUNET_free (servers);
423 * Method deciding if a preconfigured or advertisied hostlist is used on a 50:50 ratio
424 * @return uri to use, NULL if there is no URL available
430 unsigned int counter;
431 struct Hostlist *pos;
433 if (GNUNET_NO == stat_learning)
435 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
436 "Using preconfigured bootstrap server\n");
437 current_hostlist = NULL;
438 return get_bootstrap_server ();
441 if ((GNUNET_YES == stat_testing_hostlist) && (NULL != hostlist_to_test))
443 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
444 "Testing new advertised hostlist if it is obtainable\n");
445 current_hostlist = hostlist_to_test;
446 return GNUNET_strdup (hostlist_to_test->hostlist_uri);
449 if ((GNUNET_YES == stat_use_bootstrap) || (linked_list_size == 0))
451 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
452 "Using preconfigured bootstrap server\n");
453 current_hostlist = NULL;
454 return get_bootstrap_server ();
457 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, linked_list_size);
459 pos = linked_list_head;
460 while (counter < index)
465 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Using learned hostlist `%s'\n",
467 current_hostlist = pos;
468 return GNUNET_strdup (pos->hostlist_uri);
472 #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)
476 * Method to save hostlist to a file during hostlist client shutdown
477 * @param shutdown set if called because of shutdown, entries in linked list will be destroyed
480 save_hostlist_file (int shutdown);
484 * add val2 to val1 with overflow check
485 * @param val1 value 1
486 * @param val2 value 2
490 checked_add (uint64_t val1, uint64_t val2)
492 static uint64_t temp;
493 static uint64_t maxv;
506 * Subtract val2 from val1 with underflow check
507 * @param val1 value 1
508 * @param val2 value 2
512 checked_sub (uint64_t val1, uint64_t val2)
517 return (val1 - val2);
521 * 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;
650 * Clean up the state from the task that downloaded the
651 * hostlist and schedule the next task.
658 if ((stat_testing_hostlist == GNUNET_YES) &&
659 (GNUNET_NO == stat_download_successful) && (NULL != hostlist_to_test))
661 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
663 ("Advertised hostlist with URI `%s' could not be downloaded. Advertised URI gets dismissed.\n"),
664 hostlist_to_test->hostlist_uri);
667 if (stat_testing_hostlist == GNUNET_YES)
669 stat_testing_hostlist = GNUNET_NO;
671 if (NULL != hostlist_to_test)
673 GNUNET_free (hostlist_to_test);
674 hostlist_to_test = NULL;
679 mret = curl_multi_remove_handle (multi, curl);
680 if (mret != CURLM_OK)
682 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
683 "curl_multi_remove_handle", __FILE__, __LINE__,
684 curl_multi_strerror (mret));
686 mret = curl_multi_cleanup (multi);
687 if (mret != CURLM_OK)
688 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
689 "curl_multi_cleanup", __FILE__, __LINE__,
690 curl_multi_strerror (mret));
695 curl_easy_cleanup (curl);
698 GNUNET_free_non_null (current_url);
700 stat_bytes_downloaded = 0;
701 stat_download_in_progress = GNUNET_NO;
706 * Task that is run when we are ready to receive more data from the hostlist
709 * @param cls closure, unused
710 * @param tc task context, unused
713 task_download (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
717 * Ask CURL for the select set and then schedule the
718 * receiving task with the scheduler.
728 struct GNUNET_NETWORK_FDSet *grs;
729 struct GNUNET_NETWORK_FDSet *gws;
731 struct GNUNET_TIME_Relative rtime;
737 mret = curl_multi_fdset (multi, &rs, &ws, &es, &max);
738 if (mret != CURLM_OK)
740 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
741 "curl_multi_fdset", __FILE__, __LINE__,
742 curl_multi_strerror (mret));
746 mret = curl_multi_timeout (multi, &timeout);
747 if (mret != CURLM_OK)
749 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
750 "curl_multi_timeout", __FILE__, __LINE__,
751 curl_multi_strerror (mret));
756 GNUNET_TIME_relative_min (GNUNET_TIME_absolute_get_remaining (end_time),
757 GNUNET_TIME_relative_multiply
758 (GNUNET_TIME_UNIT_MILLISECONDS, timeout));
759 grs = GNUNET_NETWORK_fdset_create ();
760 gws = GNUNET_NETWORK_fdset_create ();
761 GNUNET_NETWORK_fdset_copy_native (grs, &rs, max + 1);
762 GNUNET_NETWORK_fdset_copy_native (gws, &ws, max + 1);
763 #if DEBUG_HOSTLIST_CLIENT
764 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
765 "Scheduling task for hostlist download using cURL\n");
768 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT,
769 GNUNET_SCHEDULER_NO_TASK, rtime, grs, gws,
770 &task_download, multi);
771 GNUNET_NETWORK_fdset_destroy (gws);
772 GNUNET_NETWORK_fdset_destroy (grs);
777 * Task that is run when we are ready to receive more data from the hostlist
780 * @param cls closure, unused
781 * @param tc task context, unused
784 task_download (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
790 ti_download = GNUNET_SCHEDULER_NO_TASK;
791 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
793 #if DEBUG_HOSTLIST_CLIENT
794 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
795 "Shutdown requested while trying to download hostlist from `%s'\n",
802 if (GNUNET_TIME_absolute_get_remaining (end_time).rel_value == 0)
804 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
805 _("Timeout trying to download hostlist from `%s'\n"),
811 #if DEBUG_HOSTLIST_CLIENT
812 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
813 "Ready for processing hostlist client request\n");
819 if (stat_bytes_downloaded > MAX_BYTES_PER_HOSTLISTS)
821 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
822 _("Download limit of %u bytes exceeded, stopping download\n"),
823 MAX_BYTES_PER_HOSTLISTS);
827 mret = curl_multi_perform (multi, &running);
832 msg = curl_multi_info_read (multi, &running);
833 GNUNET_break (msg != NULL);
839 if ((msg->data.result != CURLE_OK) &&
840 (msg->data.result != CURLE_GOT_NOTHING))
841 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
842 _("%s failed for `%s' at %s:%d: `%s'\n"),
843 "curl_multi_perform", current_url, __FILE__, __LINE__,
844 curl_easy_strerror (msg->data.result));
847 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
848 _("Download of hostlist `%s' completed.\n"),
850 stat_download_successful = GNUNET_YES;
852 if (GNUNET_YES == stat_testing_hostlist)
854 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
856 ("Adding successfully tested hostlist `%s' datastore.\n"),
859 hostlist_to_test = NULL;
860 stat_testing_hostlist = GNUNET_NO;
870 while ((running > 0));
873 while (mret == CURLM_CALL_MULTI_PERFORM);
875 if (mret != CURLM_OK)
877 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("%s failed at %s:%d: `%s'\n"),
878 "curl_multi_perform", __FILE__, __LINE__,
879 curl_multi_strerror (mret));
887 * Main function that will download a hostlist and process its
897 current_url = download_get_url ();
898 if (current_url == NULL)
900 curl = curl_easy_init ();
908 GNUNET_log (GNUNET_ERROR_TYPE_INFO | GNUNET_ERROR_TYPE_BULK,
909 _("Bootstrapping using hostlist at `%s'.\n"), current_url);
911 stat_download_in_progress = GNUNET_YES;
912 stat_download_successful = GNUNET_NO;
913 stat_hellos_obtained = 0;
914 stat_bytes_downloaded = 0;
916 GNUNET_STATISTICS_update (stats,
917 gettext_noop ("# hostlist downloads initiated"), 1,
920 CURL_EASY_SETOPT (curl, CURLOPT_PROXY, proxy);
923 CURL_EASY_SETOPT (curl, CURLOPT_WRITEFUNCTION, &callback_download);
929 CURL_EASY_SETOPT (curl, CURLOPT_WRITEDATA, NULL);
935 CURL_EASY_SETOPT (curl, CURLOPT_FOLLOWLOCATION, 1);
936 CURL_EASY_SETOPT (curl, CURLOPT_MAXREDIRS, 4);
937 /* no need to abort if the above failed */
938 CURL_EASY_SETOPT (curl, CURLOPT_URL, current_url);
944 CURL_EASY_SETOPT (curl, CURLOPT_FAILONERROR, 1);
946 CURL_EASY_SETOPT (curl, CURLOPT_VERBOSE, 1);
948 CURL_EASY_SETOPT (curl, CURLOPT_BUFFERSIZE, GNUNET_SERVER_MAX_MESSAGE_SIZE);
949 if (0 == strncmp (current_url, "http", 4))
950 CURL_EASY_SETOPT (curl, CURLOPT_USERAGENT, "GNUnet");
951 CURL_EASY_SETOPT (curl, CURLOPT_CONNECTTIMEOUT, 60L);
952 CURL_EASY_SETOPT (curl, CURLOPT_TIMEOUT, 60L);
954 /* this should no longer be needed; we're now single-threaded! */
955 CURL_EASY_SETOPT (curl, CURLOPT_NOSIGNAL, 1);
957 multi = curl_multi_init ();
964 mret = curl_multi_add_handle (multi, curl);
965 if (mret != CURLM_OK)
967 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
968 "curl_multi_add_handle", __FILE__, __LINE__,
969 curl_multi_strerror (mret));
970 mret = curl_multi_cleanup (multi);
971 if (mret != CURLM_OK)
972 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("%s failed at %s:%d: `%s'\n"),
973 "curl_multi_cleanup", __FILE__, __LINE__,
974 curl_multi_strerror (mret));
979 end_time = GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_MINUTES);
985 task_download_dispatcher (void *cls,
986 const struct GNUNET_SCHEDULER_TaskContext *tc)
988 ti_download_dispatcher_task = GNUNET_SCHEDULER_NO_TASK;
989 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
991 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download is initiated...\n");
992 if (GNUNET_NO == stat_download_in_progress)
994 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download can start immediately...\n");
995 download_hostlist ();
999 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1000 "Download in progess, have to wait...\n");
1001 ti_download_dispatcher_task =
1002 GNUNET_SCHEDULER_add_delayed (WAITING_INTERVALL,
1003 &task_download_dispatcher, NULL);
1008 * Task that checks if we should try to download a hostlist.
1009 * If so, we initiate the download, otherwise we schedule
1010 * this task again for a later time.
1013 task_check (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1016 struct GNUNET_TIME_Relative delay;
1018 ti_check_download = GNUNET_SCHEDULER_NO_TASK;
1019 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1022 if (stat_connection_count < MIN_CONNECTIONS)
1024 ti_download_dispatcher_task =
1025 GNUNET_SCHEDULER_add_now (&task_download_dispatcher, NULL);
1030 curl_global_cleanup ();
1031 return; /* in shutdown */
1033 delay = hostlist_delay;
1034 if (hostlist_delay.rel_value == 0)
1035 hostlist_delay = GNUNET_TIME_UNIT_SECONDS;
1037 hostlist_delay = GNUNET_TIME_relative_multiply (hostlist_delay, 2);
1038 if (hostlist_delay.rel_value >
1039 GNUNET_TIME_UNIT_HOURS.rel_value * (1 + stat_connection_count))
1041 GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS,
1042 (1 + stat_connection_count));
1043 GNUNET_STATISTICS_set (stats,
1045 ("# milliseconds between hostlist downloads"),
1046 hostlist_delay.rel_value, GNUNET_YES);
1049 delay = GNUNET_TIME_UNIT_ZERO;
1052 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1054 ("Have %u/%u connections. Will consider downloading hostlist in %llums\n"),
1055 stat_connection_count, MIN_CONNECTIONS,
1056 (unsigned long long) delay.rel_value);
1057 ti_check_download = GNUNET_SCHEDULER_add_delayed (delay, &task_check, NULL);
1062 * This tasks sets hostlist testing to allowed after intervall between to testings is reached
1064 * @param cls closure
1065 * @param tc TaskContext
1068 task_testing_intervall_reset (void *cls,
1069 const struct GNUNET_SCHEDULER_TaskContext *tc)
1071 ti_testing_intervall_task = GNUNET_SCHEDULER_NO_TASK;
1072 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1074 stat_testing_allowed = GNUNET_OK;
1075 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1076 "Testing new hostlist advertisements is allowed again\n");
1081 * Task that writes hostlist entries to a file on a regular base
1083 * @param cls closure
1084 * @param tc TaskContext
1087 task_hostlist_saving (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1089 ti_saving_task = GNUNET_SCHEDULER_NO_TASK;
1090 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1092 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Scheduled saving of hostlists\n"));
1093 save_hostlist_file (GNUNET_NO);
1095 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1096 _("Hostlists will be saved to file again in %llums\n"),
1097 (unsigned long long) SAVING_INTERVALL.rel_value);
1099 GNUNET_SCHEDULER_add_delayed (SAVING_INTERVALL, &task_hostlist_saving,
1105 * Method called whenever a given peer connects.
1107 * @param cls closure
1108 * @param peer peer identity this notification is about
1109 * @param atsi performance data
1110 * @param atsi_count number of records in 'atsi'
1113 handler_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
1114 const struct GNUNET_ATS_Information *atsi,
1115 unsigned int atsi_count)
1117 GNUNET_assert (stat_connection_count < UINT_MAX);
1118 stat_connection_count++;
1119 GNUNET_STATISTICS_update (stats, gettext_noop ("# active connections"), 1,
1125 * Method called whenever a given peer disconnects.
1127 * @param cls closure
1128 * @param peer peer identity this notification is about
1131 handler_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
1133 GNUNET_assert (stat_connection_count > 0);
1134 stat_connection_count--;
1135 GNUNET_STATISTICS_update (stats, gettext_noop ("# active connections"), -1,
1141 * Method called whenever an advertisement message arrives.
1143 * @param cls closure (always NULL)
1144 * @param peer the peer sending the message
1145 * @param message the actual message
1146 * @param atsi performance data
1147 * @param atsi_count number of records in 'atsi'
1148 * @return GNUNET_OK to keep the connection open,
1149 * GNUNET_SYSERR to close it (signal serious error)
1152 handler_advertisement (void *cls, const struct GNUNET_PeerIdentity *peer,
1153 const struct GNUNET_MessageHeader *message,
1154 const struct GNUNET_ATS_Information *atsi,
1155 unsigned int atsi_count)
1159 const struct GNUNET_MessageHeader *incoming;
1161 struct Hostlist *hostlist;
1163 GNUNET_assert (ntohs (message->type) ==
1164 GNUNET_MESSAGE_TYPE_HOSTLIST_ADVERTISEMENT);
1165 size = ntohs (message->size);
1166 if (size <= sizeof (struct GNUNET_MessageHeader))
1168 GNUNET_break_op (0);
1169 return GNUNET_SYSERR;
1171 incoming = (const struct GNUNET_MessageHeader *) message;
1172 uri = (const char *) &incoming[1];
1173 uri_size = size - sizeof (struct GNUNET_MessageHeader);
1174 if (uri[uri_size - 1] != '\0')
1176 GNUNET_break_op (0);
1177 return GNUNET_SYSERR;
1179 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1180 "Hostlist client recieved advertisement from `%s' containing URI `%s'\n",
1181 GNUNET_i2s (peer), uri);
1182 if (GNUNET_NO != linked_list_contains (uri))
1184 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "URI `%s' is already known\n", uri);
1188 if (GNUNET_NO == stat_testing_allowed)
1190 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1191 "Currently not accepting new advertisements: interval between to advertisements is not reached\n");
1192 return GNUNET_SYSERR;
1194 if (GNUNET_YES == stat_testing_hostlist)
1196 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1197 "Currently not accepting new advertisements: we are already testing a hostlist\n");
1198 return GNUNET_SYSERR;
1201 hostlist = GNUNET_malloc (sizeof (struct Hostlist) + uri_size);
1202 hostlist->hostlist_uri = (const char *) &hostlist[1];
1203 memcpy (&hostlist[1], uri, uri_size);
1204 hostlist->time_creation = GNUNET_TIME_absolute_get ();
1205 hostlist->time_last_usage = GNUNET_TIME_absolute_get_zero ();
1206 hostlist->quality = HOSTLIST_INITIAL;
1207 hostlist_to_test = hostlist;
1209 stat_testing_hostlist = GNUNET_YES;
1210 stat_testing_allowed = GNUNET_NO;
1211 ti_testing_intervall_task =
1212 GNUNET_SCHEDULER_add_delayed (TESTING_INTERVAL,
1213 &task_testing_intervall_reset, NULL);
1215 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1216 "Testing new hostlist advertisements is locked for the next %u ms\n",
1217 TESTING_INTERVAL.rel_value);
1219 ti_download_dispatcher_task =
1220 GNUNET_SCHEDULER_add_now (&task_download_dispatcher, NULL);
1228 * Continuation called by the statistics code once
1229 * we go the stat. Initiates hostlist download scheduling.
1231 * @param cls closure
1232 * @param success GNUNET_OK if statistics were
1233 * successfully obtained, GNUNET_SYSERR if not.
1236 primary_task (void *cls, int success)
1239 return; /* in shutdown */
1240 #if DEBUG_HOSTLIST_CLIENT
1241 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1242 "Statistics request done, scheduling hostlist download\n");
1244 ti_check_download = GNUNET_SCHEDULER_add_now (&task_check, NULL);
1249 process_stat (void *cls, const char *subsystem, const char *name,
1250 uint64_t value, int is_persistent)
1252 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1253 _("Initial time between hostlist downloads is %llums\n"),
1254 (unsigned long long) value);
1255 hostlist_delay.rel_value = value;
1260 * Method to load persistent hostlist file during hostlist client startup
1263 load_hostlist_file ()
1268 struct Hostlist *hostlist;
1271 uint32_t times_used;
1272 uint32_t hellos_returned;
1279 GNUNET_CONFIGURATION_get_value_filename (cfg, "HOSTLIST", "HOSTLISTFILE",
1282 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1284 ("No `%s' specified in `%s' configuration, cannot load hostlists from file.\n"),
1285 "HOSTLISTFILE", "HOSTLIST");
1289 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1290 _("Loading saved hostlist entries from file `%s' \n"), filename);
1291 if (GNUNET_NO == GNUNET_DISK_file_test (filename))
1293 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1294 _("Hostlist file `%s' is not existing\n"), filename);
1295 GNUNET_free (filename);
1299 struct GNUNET_BIO_ReadHandle *rh = GNUNET_BIO_read_open (filename);
1303 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1305 ("Could not open file `%s' for reading to load hostlists: %s\n"),
1306 filename, STRERROR (errno));
1307 GNUNET_free (filename);
1312 while ((GNUNET_OK == GNUNET_BIO_read_string (rh, "url", &uri, MAX_URL_LEN)) &&
1313 (NULL != uri) && (GNUNET_OK == GNUNET_BIO_read_int32 (rh, ×_used))
1314 && (GNUNET_OK == GNUNET_BIO_read_int64 (rh, &quality)) &&
1315 (GNUNET_OK == GNUNET_BIO_read_int64 (rh, &last_used)) &&
1316 (GNUNET_OK == GNUNET_BIO_read_int64 (rh, &created)) &&
1317 (GNUNET_OK == GNUNET_BIO_read_int32 (rh, &hellos_returned)))
1319 hostlist = GNUNET_malloc (sizeof (struct Hostlist) + strlen (uri) + 1);
1320 hostlist->hello_count = hellos_returned;
1321 hostlist->hostlist_uri = (const char *) &hostlist[1];
1322 memcpy (&hostlist[1], uri, strlen (uri) + 1);
1323 hostlist->quality = quality;
1324 hostlist->time_creation.abs_value = created;
1325 hostlist->time_last_usage.abs_value = last_used;
1326 GNUNET_CONTAINER_DLL_insert (linked_list_head, linked_list_tail, hostlist);
1328 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1329 "Added hostlist entry eith URI `%s' \n",
1330 hostlist->hostlist_uri);
1334 if (counter >= MAX_NUMBER_HOSTLISTS)
1338 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("%u hostlist URIs loaded from file\n"),
1340 GNUNET_STATISTICS_set (stats, gettext_noop ("# hostlist URIs read from file"),
1341 counter, GNUNET_YES);
1342 GNUNET_STATISTICS_set (stats, gettext_noop ("# advertised hostlist URIs"),
1343 linked_list_size, GNUNET_NO);
1345 GNUNET_free_non_null (uri);
1347 GNUNET_BIO_read_close (rh, &emsg);
1350 GNUNET_free (filename);
1355 * Method to save persistent hostlist file during hostlist client shutdown
1356 * @param shutdown set if called because of shutdown, entries in linked list will be destroyed
1359 save_hostlist_file (int shutdown)
1362 struct Hostlist *pos;
1363 struct GNUNET_BIO_WriteHandle *wh;
1368 GNUNET_CONFIGURATION_get_value_filename (cfg, "HOSTLIST", "HOSTLISTFILE",
1371 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1373 ("No `%s' specified in `%s' configuration, cannot save hostlists to file.\n"),
1374 "HOSTLISTFILE", "HOSTLIST");
1377 if (GNUNET_SYSERR == GNUNET_DISK_directory_create_for_file (filename))
1379 GNUNET_free (filename);
1382 wh = GNUNET_BIO_write_open (filename);
1385 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1387 ("Could not open file `%s' for writing to save hostlists: %s\n"),
1388 filename, STRERROR (errno));
1389 GNUNET_free (filename);
1392 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Writing %u hostlist URIs to `%s'\n"),
1393 linked_list_size, filename);
1394 /* add code to write hostlists to file using bio */
1397 while (NULL != (pos = linked_list_head))
1399 if (GNUNET_YES == shutdown)
1401 GNUNET_CONTAINER_DLL_remove (linked_list_head, linked_list_tail, pos);
1404 if (GNUNET_YES == ok)
1406 if ((GNUNET_OK != GNUNET_BIO_write_string (wh, pos->hostlist_uri)) ||
1407 (GNUNET_OK != GNUNET_BIO_write_int32 (wh, pos->times_used)) ||
1408 (GNUNET_OK != GNUNET_BIO_write_int64 (wh, pos->quality)) ||
1410 GNUNET_BIO_write_int64 (wh, pos->time_last_usage.abs_value)) ||
1412 GNUNET_BIO_write_int64 (wh, pos->time_creation.abs_value)) ||
1413 (GNUNET_OK != GNUNET_BIO_write_int32 (wh, pos->hello_count)))
1415 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1416 _("Error writing hostlist URIs to file `%s'\n"), filename);
1421 if (GNUNET_YES == shutdown)
1424 if (counter >= MAX_NUMBER_HOSTLISTS)
1427 GNUNET_STATISTICS_set (stats,
1428 gettext_noop ("# hostlist URIs written to file"),
1429 counter, GNUNET_YES);
1431 if (GNUNET_OK != GNUNET_BIO_write_close (wh))
1432 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1433 _("Error writing hostlist URIs to file `%s'\n"), filename);
1434 GNUNET_free (filename);
1438 * Start downloading hostlists from hostlist servers as necessary.
1441 GNUNET_HOSTLIST_client_start (const struct GNUNET_CONFIGURATION_Handle *c,
1442 struct GNUNET_STATISTICS_Handle *st,
1443 GNUNET_CORE_ConnectEventHandler *ch,
1444 GNUNET_CORE_DisconnectEventHandler *dh,
1445 GNUNET_CORE_MessageCallback *msgh, int learn)
1450 if (0 != curl_global_init (CURL_GLOBAL_WIN32))
1453 return GNUNET_SYSERR;
1455 transport = GNUNET_TRANSPORT_connect (c, NULL, NULL, NULL, NULL, NULL);
1456 if (NULL == transport)
1458 curl_global_cleanup ();
1459 return GNUNET_SYSERR;
1464 GNUNET_CONFIGURATION_get_value_string (cfg, "HOSTLIST", "HTTP-PROXY",
1467 stat_learning = learn;
1468 *ch = &handler_connect;
1469 *dh = &handler_disconnect;
1470 linked_list_head = NULL;
1471 linked_list_tail = NULL;
1472 stat_use_bootstrap = GNUNET_YES;
1473 stat_testing_hostlist = GNUNET_NO;
1474 stat_testing_allowed = GNUNET_YES;
1476 if (GNUNET_YES == stat_learning)
1478 *msgh = &handler_advertisement;
1479 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1480 _("Learning is enabled on this peer\n"));
1481 load_hostlist_file ();
1482 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1483 _("Hostlists will be saved to file again in %llums\n"),
1484 (unsigned long long) SAVING_INTERVALL.rel_value);
1486 GNUNET_SCHEDULER_add_delayed (SAVING_INTERVALL, &task_hostlist_saving,
1491 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1492 _("Learning is not enabled on this peer\n"));
1495 GNUNET_CONFIGURATION_get_value_filename (cfg, "HOSTLIST",
1496 "HOSTLISTFILE", &filename))
1498 if (GNUNET_YES == GNUNET_DISK_file_test (filename))
1500 result = remove (filename);
1502 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1504 ("Since learning is not enabled on this peer, hostlist file `%s' was removed\n"),
1507 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1508 _("Hostlist file `%s' could not be removed\n"), filename);
1511 GNUNET_free (filename);
1513 GNUNET_STATISTICS_get (stats, "hostlist",
1515 ("# milliseconds between hostlist downloads"),
1516 GNUNET_TIME_UNIT_MINUTES, &primary_task, &process_stat,
1523 * Stop downloading hostlists from hostlist servers as necessary.
1526 GNUNET_HOSTLIST_client_stop ()
1528 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Hostlist client shutdown\n");
1529 #if DEBUG_HOSTLIST_CLIENT
1530 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Hostlist client shutdown\n");
1532 if (GNUNET_YES == stat_learning)
1533 save_hostlist_file (GNUNET_YES);
1535 if (ti_saving_task != GNUNET_SCHEDULER_NO_TASK)
1537 GNUNET_SCHEDULER_cancel (ti_saving_task);
1540 if (ti_download_dispatcher_task != GNUNET_SCHEDULER_NO_TASK)
1542 GNUNET_SCHEDULER_cancel (ti_download_dispatcher_task);
1544 if (ti_testing_intervall_task != GNUNET_SCHEDULER_NO_TASK)
1546 GNUNET_SCHEDULER_cancel (ti_testing_intervall_task);
1548 if (ti_download != GNUNET_SCHEDULER_NO_TASK)
1550 GNUNET_SCHEDULER_cancel (ti_download);
1552 if (ti_check_download != GNUNET_SCHEDULER_NO_TASK)
1554 GNUNET_SCHEDULER_cancel (ti_check_download);
1555 curl_global_cleanup ();
1557 if (transport != NULL)
1559 GNUNET_TRANSPORT_disconnect (transport);
1562 GNUNET_assert (NULL == transport);
1563 GNUNET_free_non_null (proxy);
1568 /* end of hostlist-client.c */