2 This file is part of GNUnet.
3 (C) 2009, 2010, 2011 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 nse/gnunet-service-nse.c
23 * @brief network size estimation service
24 * @author Nathan Evans
25 * @author Christian Grothoff
27 * The purpose of this service is to estimate the size of the network.
28 * Given a specified interval, each peer hashes the most recent
29 * timestamp which is evenly divisible by that interval. This hash is
30 * compared in distance to the peer identity to choose an offset. The
31 * closer the peer identity to the hashed timestamp, the earlier the
32 * peer sends out a "nearest peer" message. The closest peer's
33 * message should thus be received before any others, which stops
34 * those peer from sending their messages at a later duration. So
35 * every peer should receive the same nearest peer message, and from
36 * this can calculate the expected number of peers in the network.
40 #include "gnunet_util_lib.h"
41 #include "gnunet_constants.h"
42 #include "gnunet_protocols.h"
43 #include "gnunet_signatures.h"
44 #include "gnunet_statistics_service.h"
45 #include "gnunet_core_service.h"
46 #include "gnunet_nse_service.h"
50 * Should messages be delayed randomly? This option should be set to
51 * GNUNET_NO only for experiments, not in production. It should also
52 * be removed once the initial experiments have been completed.
54 #define USE_RANDOM_DELAYS GNUNET_YES
57 * Should we generate a histogram with the time stamps of when we received
58 * NSE messages to disk? (for performance evaluation only, not useful in
59 * production). The associated code should also probably be removed
60 * once we're done with experiments.
62 #define ENABLE_HISTOGRAM GNUNET_NO
65 * Over how many values do we calculate the weighted average?
67 #define HISTORY_SIZE 8
70 * Size of the queue to core.
72 #define CORE_QUEUE_SIZE 2
75 * Message priority to use.
77 #define NSE_PRIORITY 5
80 #define log2(a) (log(a)/log(2))
84 * Amount of work required (W-bit collisions) for NSE proofs, in collision-bits.
86 static unsigned long long nse_work_required;
89 * Interval for sending network size estimation flood requests.
91 static struct GNUNET_TIME_Relative gnunet_nse_interval;
94 * Interval between proof find runs.
96 static struct GNUNET_TIME_Relative proof_find_delay;
100 * Handle for writing when we received messages to disk.
102 static struct GNUNET_BIO_WriteHandle *wh;
107 * Per-peer information.
113 * Pending message for this peer.
115 struct GNUNET_MessageHeader *pending_message;
118 * Core handle for sending messages to this peer.
120 struct GNUNET_CORE_TransmitHandle *th;
123 * What is the identity of the peer?
125 struct GNUNET_PeerIdentity id;
128 * Task scheduled to send message to this peer.
130 GNUNET_SCHEDULER_TaskIdentifier transmit_task;
133 * Did we receive or send a message about the previous round
134 * to this peer yet? GNUNET_YES if the previous round has
135 * been taken care of.
142 * Network size estimate reply; sent when "this"
143 * peer's timer has run out before receiving a
144 * valid reply from another peer.
146 struct GNUNET_NSE_FloodMessage
149 * Type: GNUNET_MESSAGE_TYPE_NSE_P2P_FLOOD
151 struct GNUNET_MessageHeader header;
154 * Number of hops this message has taken so far.
156 uint32_t hop_count GNUNET_PACKED;
161 struct GNUNET_CRYPTO_RsaSignaturePurpose purpose;
164 * The current timestamp value (which all
165 * peers should agree on).
167 struct GNUNET_TIME_AbsoluteNBO timestamp;
170 * Number of matching bits between the hash
171 * of timestamp and the initiator's public
174 uint32_t matching_bits GNUNET_PACKED;
177 * Public key of the originator.
179 struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded pkey;
182 * Proof of work, causing leading zeros when hashed with pkey.
184 uint64_t proof_of_work GNUNET_PACKED;
187 * Signature (over range specified in purpose).
189 struct GNUNET_CRYPTO_RsaSignature signature;
194 * Handle to our current configuration.
196 static const struct GNUNET_CONFIGURATION_Handle *cfg;
199 * Handle to the statistics service.
201 static struct GNUNET_STATISTICS_Handle *stats;
204 * Handle to the core service.
206 static struct GNUNET_CORE_Handle *coreAPI;
209 * Map of all connected peers.
211 static struct GNUNET_CONTAINER_MultiHashMap *peers;
214 * The current network size estimate. Number of bits matching on
217 static double current_size_estimate;
220 * The standard deviation of the last HISTORY_SIZE network
223 static double current_std_dev = NAN;
226 * Current hop counter estimate (estimate for network diameter).
228 static uint32_t hop_count_max;
231 * Message for the next round, if we got any.
233 static struct GNUNET_NSE_FloodMessage next_message;
236 * Array of recent size estimate messages.
238 static struct GNUNET_NSE_FloodMessage size_estimate_messages[HISTORY_SIZE];
241 * Index of most recent estimate.
243 static unsigned int estimate_index;
246 * Number of valid entries in the history.
248 static unsigned int estimate_count;
251 * Task scheduled to update our flood message for the next round.
253 static GNUNET_SCHEDULER_TaskIdentifier flood_task;
256 * Task scheduled to compute our proof.
258 static GNUNET_SCHEDULER_TaskIdentifier proof_task;
261 * Notification context, simplifies client broadcasts.
263 static struct GNUNET_SERVER_NotificationContext *nc;
266 * The next major time.
268 static struct GNUNET_TIME_Absolute next_timestamp;
271 * The current major time.
273 static struct GNUNET_TIME_Absolute current_timestamp;
276 * The public key of this peer.
278 static struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded my_public_key;
281 * The private key of this peer.
283 static struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key;
286 * The peer identity of this peer.
288 static struct GNUNET_PeerIdentity my_identity;
291 * Proof of work for this peer.
293 static uint64_t my_proof;
297 * Initialize a message to clients with the current network
300 * @param em message to fill in
303 setup_estimate_message (struct GNUNET_NSE_ClientMessage *em)
313 /* Weighted incremental algorithm for stddev according to West (1979) */
324 for (i = 0; i < estimate_count; i++)
327 htonl (size_estimate_messages
328 [(estimate_index - i +
329 HISTORY_SIZE) % HISTORY_SIZE].matching_bits);
330 weight = 1; /* was: estimate_count + 1 - i; */
332 temp = weight + sumweight;
334 r = q * weight / temp;
335 sum += sumweight * q * r;
339 variance = sum / (sumweight - 1.0);
341 /* trivial version for debugging */
344 /* non-weighted trivial version */
347 for (i = 0; i < estimate_count; i++)
349 val = htonl (size_estimate_messages
350 [(estimate_index - i +
351 HISTORY_SIZE) % HISTORY_SIZE].matching_bits);
355 mean = sum / estimate_count;
356 variance = vsq + mean * mean - 2 * mean * sum; // terrible for numerical stability...
358 GNUNET_assert (variance >= 0);
359 std_dev = sqrt (variance);
360 current_std_dev = std_dev;
361 current_size_estimate = mean;
363 em->header.size = htons (sizeof (struct GNUNET_NSE_ClientMessage));
364 em->header.type = htons (GNUNET_MESSAGE_TYPE_NSE_ESTIMATE);
365 em->reserved = htonl (0);
366 em->timestamp = GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
367 em->size_estimate = mean - 0.332747;
368 nsize = log2 (GNUNET_CONTAINER_multihashmap_size (peers) + 1);
369 if (em->size_estimate < nsize)
370 em->size_estimate = nsize;
371 em->std_deviation = std_dev;
372 GNUNET_STATISTICS_set (stats, "# nodes in the network (estimate)",
373 (uint64_t) pow (2, mean - 1.0 / 3.0), GNUNET_NO);
378 * Handler for START message from client, triggers an
379 * immediate current network estimate notification.
380 * Also, we remember the client for updates upon future
381 * estimate measurements.
384 * @param client who sent the message
385 * @param message the message received
388 handle_start_message (void *cls, struct GNUNET_SERVER_Client *client,
389 const struct GNUNET_MessageHeader *message)
391 struct GNUNET_NSE_ClientMessage em;
394 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received START message from client\n");
396 GNUNET_SERVER_notification_context_add (nc, client);
397 setup_estimate_message (&em);
398 GNUNET_SERVER_notification_context_unicast (nc, client, &em.header,
400 GNUNET_SERVER_receive_done (client, GNUNET_OK);
405 * How long should we delay a message to go the given number of
408 * @param matching_bits number of matching bits to consider
411 get_matching_bits_delay (uint32_t matching_bits)
413 /* Calculated as: S + f/2 - (f / pi) * (atan(x - p')) */
414 // S is next_timestamp (ignored in return value)
415 // f is frequency (gnunet_nse_interval)
416 // x is matching_bits
417 // p' is current_size_estimate
418 return ((double) gnunet_nse_interval.rel_value / (double) 2.0) -
419 ((gnunet_nse_interval.rel_value / M_PI) *
420 atan (matching_bits - current_size_estimate));
425 * What delay randomization should we apply for a given number of matching bits?
427 * @param matching_bits number of matching bits
428 * @return random delay to apply
430 static struct GNUNET_TIME_Relative
431 get_delay_randomization (uint32_t matching_bits)
433 #if USE_RANDOM_DELAYS
434 struct GNUNET_TIME_Relative ret;
436 if (matching_bits == 0)
437 return GNUNET_TIME_UNIT_ZERO;
439 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
440 (uint32_t) (get_matching_bits_delay
442 1) / (double) (hop_count_max +
446 return GNUNET_TIME_UNIT_ZERO;
452 * Get the number of matching bits that the given timestamp has to the given peer ID.
454 * @param timestamp time to generate key
455 * @param id peer identity to compare with
456 * @return number of matching bits
459 get_matching_bits (struct GNUNET_TIME_Absolute timestamp,
460 const struct GNUNET_PeerIdentity *id)
462 GNUNET_HashCode timestamp_hash;
464 GNUNET_CRYPTO_hash (×tamp.abs_value, sizeof (timestamp.abs_value),
466 return GNUNET_CRYPTO_hash_matching_bits (×tamp_hash, &id->hashPubKey);
471 * Get the transmission delay that should be applied for a
474 * @param round_offset -1 for the previous round (random delay between 0 and 50ms)
475 * 0 for the current round (based on our proximity to time key)
476 * @return delay that should be applied
478 static struct GNUNET_TIME_Relative
479 get_transmit_delay (int round_offset)
481 struct GNUNET_TIME_Relative ret;
482 struct GNUNET_TIME_Absolute tgt;
484 uint32_t matching_bits;
486 switch (round_offset)
489 /* previous round is randomized between 0 and 50 ms */
490 #if USE_RANDOM_DELAYS
491 ret.rel_value = GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, 50);
493 ret = GNUNET_TIME_UNIT_ZERO;
496 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
497 "Transmitting previous round behind schedule in %llu ms\n",
498 (unsigned long long) ret.rel_value);
502 /* current round is based on best-known matching_bits */
504 ntohl (size_estimate_messages[estimate_index].matching_bits);
505 dist_delay = get_matching_bits_delay (matching_bits);
506 dist_delay += get_delay_randomization (matching_bits).rel_value;
507 ret.rel_value = (uint64_t) dist_delay;
509 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
510 "For round %llu, delay for %u matching bits is %llu ms\n",
511 (unsigned long long) current_timestamp.abs_value,
512 (unsigned int) matching_bits,
513 (unsigned long long) ret.rel_value);
515 /* now consider round start time and add delay to it */
516 tgt = GNUNET_TIME_absolute_add (current_timestamp, ret);
517 return GNUNET_TIME_absolute_get_remaining (tgt);
520 return GNUNET_TIME_UNIT_FOREVER_REL;
525 * Task that triggers a NSE P2P transmission.
527 * @param cls the 'struct NSEPeerEntry'
528 * @param tc scheduler context
531 transmit_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
535 * Called when core is ready to send a message we asked for
536 * out to the destination.
538 * @param cls closure (NULL)
539 * @param size number of bytes available in buf
540 * @param buf where the callee should write the message
541 * @return number of bytes written to buf
544 transmit_ready (void *cls, size_t size, void *buf)
546 struct NSEPeerEntry *peer_entry = cls;
549 peer_entry->th = NULL;
552 /* client disconnected */
555 GNUNET_assert (size >= sizeof (struct GNUNET_NSE_FloodMessage));
556 idx = estimate_index;
557 if (peer_entry->previous_round == GNUNET_NO)
559 idx = (idx + HISTORY_SIZE - 1) % HISTORY_SIZE;
560 peer_entry->previous_round = GNUNET_YES;
561 peer_entry->transmit_task =
562 GNUNET_SCHEDULER_add_delayed (get_transmit_delay (0), &transmit_task,
565 if ((ntohl (size_estimate_messages[idx].hop_count) == 0) &&
566 (GNUNET_SCHEDULER_NO_TASK != proof_task))
568 GNUNET_STATISTICS_update (stats,
569 "# flood messages not generated (no proof yet)",
574 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
575 "In round %llu, sending to `%s' estimate with %u bits\n",
577 GNUNET_TIME_absolute_ntoh (size_estimate_messages[idx].
578 timestamp).abs_value,
579 GNUNET_i2s (&peer_entry->id),
580 (unsigned int) ntohl (size_estimate_messages[idx].matching_bits));
582 if (ntohl (size_estimate_messages[idx].hop_count) == 0)
583 GNUNET_STATISTICS_update (stats, "# flood messages started", 1, GNUNET_NO);
584 GNUNET_STATISTICS_update (stats, "# flood messages transmitted", 1,
586 memcpy (buf, &size_estimate_messages[idx],
587 sizeof (struct GNUNET_NSE_FloodMessage));
588 GNUNET_STATISTICS_update (stats, "# flood messages sent", 1, GNUNET_NO);
589 return sizeof (struct GNUNET_NSE_FloodMessage);
594 * Task that triggers a NSE P2P transmission.
596 * @param cls the 'struct NSEPeerEntry'
597 * @param tc scheduler context
600 transmit_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
602 struct NSEPeerEntry *peer_entry = cls;
604 peer_entry->transmit_task = GNUNET_SCHEDULER_NO_TASK;
605 GNUNET_assert (NULL == peer_entry->th);
607 GNUNET_CORE_notify_transmit_ready (coreAPI, GNUNET_NO, NSE_PRIORITY,
608 GNUNET_TIME_UNIT_FOREVER_REL,
611 GNUNET_NSE_FloodMessage),
612 &transmit_ready, peer_entry);
617 * We've sent on our flood message or one that we received which was
618 * validated and closer than ours. Update the global list of recent
619 * messages and the average. Also re-broadcast the message to any
623 update_network_size_estimate ()
625 struct GNUNET_NSE_ClientMessage em;
627 setup_estimate_message (&em);
628 GNUNET_SERVER_notification_context_broadcast (nc, &em.header, GNUNET_YES);
633 * Setup a flood message in our history array at the given
634 * slot offset for the given timestamp.
636 * @param slot index to use
637 * @param ts timestamp to use
640 setup_flood_message (unsigned int slot, struct GNUNET_TIME_Absolute ts)
642 struct GNUNET_NSE_FloodMessage *fm;
643 uint32_t matching_bits;
645 matching_bits = get_matching_bits (ts, &my_identity);
646 fm = &size_estimate_messages[slot];
647 fm->header.size = htons (sizeof (struct GNUNET_NSE_FloodMessage));
648 fm->header.type = htons (GNUNET_MESSAGE_TYPE_NSE_P2P_FLOOD);
649 fm->hop_count = htonl (0);
650 fm->purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_NSE_SEND);
652 htonl (sizeof (struct GNUNET_NSE_FloodMessage) -
653 sizeof (struct GNUNET_MessageHeader) - sizeof (uint32_t) -
654 sizeof (struct GNUNET_CRYPTO_RsaSignature));
655 fm->matching_bits = htonl (matching_bits);
656 fm->timestamp = GNUNET_TIME_absolute_hton (ts);
657 fm->pkey = my_public_key;
658 fm->proof_of_work = my_proof;
659 GNUNET_assert (GNUNET_OK ==
660 GNUNET_CRYPTO_rsa_sign (my_private_key, &fm->purpose,
666 * Schedule transmission for the given peer for the current round based
667 * on what we know about the desired delay.
670 * @param key hash of peer identity
671 * @param value the 'struct NSEPeerEntry'
672 * @return GNUNET_OK (continue to iterate)
675 schedule_current_round (void *cls, const GNUNET_HashCode * key, void *value)
677 struct NSEPeerEntry *peer_entry = value;
678 struct GNUNET_TIME_Relative delay;
680 if (peer_entry->th != NULL)
682 peer_entry->previous_round = GNUNET_NO;
685 if (peer_entry->transmit_task != GNUNET_SCHEDULER_NO_TASK)
687 GNUNET_SCHEDULER_cancel (peer_entry->transmit_task);
688 peer_entry->previous_round = GNUNET_NO;
691 get_transmit_delay ((peer_entry->previous_round == GNUNET_NO) ? -1 : 0);
692 peer_entry->transmit_task =
693 GNUNET_SCHEDULER_add_delayed (delay, &transmit_task, peer_entry);
699 * Update our flood message to be sent (and our timestamps).
702 * @param tc context for this message
705 update_flood_message (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
707 struct GNUNET_TIME_Relative offset;
710 flood_task = GNUNET_SCHEDULER_NO_TASK;
711 offset = GNUNET_TIME_absolute_get_remaining (next_timestamp);
712 if (0 != offset.rel_value)
714 /* somehow run early, delay more */
716 GNUNET_SCHEDULER_add_delayed (offset, &update_flood_message, NULL);
719 current_timestamp = next_timestamp;
721 GNUNET_TIME_absolute_add (current_timestamp, gnunet_nse_interval);
722 estimate_index = (estimate_index + 1) % HISTORY_SIZE;
723 if (estimate_count < HISTORY_SIZE)
725 if (next_timestamp.abs_value ==
726 GNUNET_TIME_absolute_ntoh (next_message.timestamp).abs_value)
728 /* we received a message for this round way early, use it! */
729 size_estimate_messages[estimate_index] = next_message;
730 size_estimate_messages[estimate_index].hop_count =
731 htonl (1 + ntohl (next_message.hop_count));
734 setup_flood_message (estimate_index, current_timestamp);
735 next_message.matching_bits = htonl (0); /* reset for 'next' round */
737 for (i = 0; i < HISTORY_SIZE; i++)
739 GNUNET_MAX (ntohl (size_estimate_messages[i].hop_count), hop_count_max);
740 GNUNET_CONTAINER_multihashmap_iterate (peers, &schedule_current_round, NULL);
742 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
743 (next_timestamp), &update_flood_message,
749 * Count the leading zeroes in hash.
752 * @return the number of leading zero bits.
755 count_leading_zeroes (const GNUNET_HashCode * hash)
757 unsigned int hash_count;
760 while ((0 == GNUNET_CRYPTO_hash_get_bit (hash, hash_count)))
767 * Check whether the given public key
768 * and integer are a valid proof of work.
770 * @param pkey the public key
771 * @param val the integer
773 * @return GNUNET_YES if valid, GNUNET_NO if not
776 check_proof_of_work (const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *pkey,
779 char buf[sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded) +
781 GNUNET_HashCode result;
783 memcpy (buf, &val, sizeof (val));
784 memcpy (&buf[sizeof (val)], pkey,
785 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
786 GNUNET_CRYPTO_hash (buf, sizeof (buf), &result);
787 return (count_leading_zeroes (&result) >=
788 nse_work_required) ? GNUNET_YES : GNUNET_NO;
793 * Write our current proof to disk.
801 GNUNET_CONFIGURATION_get_value_filename (cfg, "NSE", "PROOFFILE", &proof))
803 if (sizeof (my_proof) !=
804 GNUNET_DISK_fn_write (proof, &my_proof, sizeof (my_proof),
805 GNUNET_DISK_PERM_USER_READ |
806 GNUNET_DISK_PERM_USER_WRITE))
807 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "write", proof);
814 * Find our proof of work.
816 * @param cls closure (unused)
817 * @param tc task context
820 find_proof (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
822 #define ROUND_SIZE 10
824 char buf[sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded) +
826 GNUNET_HashCode result;
829 proof_task = GNUNET_SCHEDULER_NO_TASK;
830 memcpy (&buf[sizeof (uint64_t)], &my_public_key,
831 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
834 while ((counter != UINT64_MAX) && (i < ROUND_SIZE))
836 memcpy (buf, &counter, sizeof (uint64_t));
837 GNUNET_CRYPTO_hash (buf, sizeof (buf), &result);
838 if (nse_work_required <= count_leading_zeroes (&result))
842 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Proof of work found: %llu!\n",
843 (unsigned long long) GNUNET_ntohll (counter));
845 for (i = 0; i < HISTORY_SIZE; i++)
846 if (ntohl (size_estimate_messages[i].hop_count) == 0)
848 size_estimate_messages[i].proof_of_work = my_proof;
849 GNUNET_assert (GNUNET_OK ==
850 GNUNET_CRYPTO_rsa_sign (my_private_key,
851 &size_estimate_messages
853 &size_estimate_messages
862 if (my_proof / (100 * ROUND_SIZE) < counter / (100 * ROUND_SIZE))
865 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Testing proofs currently at %llu\n",
866 (unsigned long long) counter);
868 /* remember progress every 100 rounds */
877 GNUNET_SCHEDULER_add_delayed (proof_find_delay, &find_proof, NULL);
882 * An incoming flood message has been received which claims
883 * to have more bits matching than any we know in this time
884 * period. Verify the signature and/or proof of work.
886 * @param incoming_flood the message to verify
888 * @return GNUNET_YES if the message is verified
889 * GNUNET_NO if the key/signature don't verify
892 verify_message_crypto (const struct GNUNET_NSE_FloodMessage *incoming_flood)
895 check_proof_of_work (&incoming_flood->pkey,
896 incoming_flood->proof_of_work))
898 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Proof of work invalid: %llu!\n"),
900 GNUNET_ntohll (incoming_flood->proof_of_work));
905 GNUNET_CRYPTO_rsa_verify (GNUNET_SIGNATURE_PURPOSE_NSE_SEND,
906 &incoming_flood->purpose,
907 &incoming_flood->signature,
908 &incoming_flood->pkey))
918 * Update transmissions for the given peer for the current round based
919 * on updated proximity information.
921 * @param cls peer entry to exclude from updates
922 * @param key hash of peer identity
923 * @param value the 'struct NSEPeerEntry'
924 * @return GNUNET_OK (continue to iterate)
927 update_flood_times (void *cls, const GNUNET_HashCode * key, void *value)
929 struct NSEPeerEntry *exclude = cls;
930 struct NSEPeerEntry *peer_entry = value;
931 struct GNUNET_TIME_Relative delay;
933 if (peer_entry->th != NULL)
934 return GNUNET_OK; /* already active */
935 if (peer_entry == exclude)
936 return GNUNET_OK; /* trigger of the update */
937 if (peer_entry->previous_round == GNUNET_NO)
939 /* still stuck in previous round, no point to update, check that
940 * we are active here though... */
941 GNUNET_break ((peer_entry->transmit_task != GNUNET_SCHEDULER_NO_TASK) ||
942 (peer_entry->th != NULL));
945 if (peer_entry->transmit_task != GNUNET_SCHEDULER_NO_TASK)
947 GNUNET_SCHEDULER_cancel (peer_entry->transmit_task);
948 peer_entry->transmit_task = GNUNET_SCHEDULER_NO_TASK;
950 delay = get_transmit_delay (0);
951 peer_entry->transmit_task =
952 GNUNET_SCHEDULER_add_delayed (delay, &transmit_task, peer_entry);
958 * Core handler for size estimate flooding messages.
960 * @param cls closure unused
961 * @param message message
962 * @param peer peer identity this message is from (ignored)
963 * @param atsi performance data (ignored)
964 * @param atsi_count number of records in 'atsi'
967 handle_p2p_size_estimate (void *cls, const struct GNUNET_PeerIdentity *peer,
968 const struct GNUNET_MessageHeader *message,
969 const struct GNUNET_ATS_Information *atsi,
970 unsigned int atsi_count)
972 const struct GNUNET_NSE_FloodMessage *incoming_flood;
973 struct GNUNET_TIME_Absolute ts;
974 struct NSEPeerEntry *peer_entry;
975 uint32_t matching_bits;
980 GNUNET_BIO_write_int64 (wh, GNUNET_TIME_absolute_get ().abs_value);
982 incoming_flood = (const struct GNUNET_NSE_FloodMessage *) message;
983 GNUNET_STATISTICS_update (stats, "# flood messages received", 1, GNUNET_NO);
984 matching_bits = ntohl (incoming_flood->matching_bits);
989 struct GNUNET_PeerIdentity os;
991 GNUNET_CRYPTO_hash (&incoming_flood->pkey,
992 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
994 GNUNET_snprintf (origin, sizeof (origin), "%s", GNUNET_i2s (&os));
995 GNUNET_snprintf (pred, sizeof (pred), "%s", GNUNET_i2s (peer));
996 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
997 "Flood at %llu from `%s' via `%s' at `%s' with bits %u\n",
999 GNUNET_TIME_absolute_ntoh (incoming_flood->timestamp).abs_value,
1000 origin, pred, GNUNET_i2s (&my_identity),
1001 (unsigned int) matching_bits);
1005 peer_entry = GNUNET_CONTAINER_multihashmap_get (peers, &peer->hashPubKey);
1006 if (NULL == peer_entry)
1012 ts = GNUNET_TIME_absolute_ntoh (incoming_flood->timestamp);
1014 if (ts.abs_value == current_timestamp.abs_value)
1015 idx = estimate_index;
1016 else if (ts.abs_value ==
1017 current_timestamp.abs_value - gnunet_nse_interval.rel_value)
1018 idx = (estimate_index + HISTORY_SIZE - 1) % HISTORY_SIZE;
1019 else if (ts.abs_value ==
1020 next_timestamp.abs_value - gnunet_nse_interval.rel_value)
1022 if (matching_bits <= ntohl (next_message.matching_bits))
1023 return GNUNET_OK; /* ignore, simply too early/late */
1024 if (GNUNET_YES != verify_message_crypto (incoming_flood))
1026 GNUNET_break_op (0);
1029 next_message = *incoming_flood;
1034 GNUNET_STATISTICS_update (stats,
1035 "# flood messages discarded (clock skew too large)",
1039 if (0 == (memcmp (peer, &my_identity, sizeof (struct GNUNET_PeerIdentity))))
1041 /* send to self, update our own estimate IF this also comes from us! */
1043 memcmp (&incoming_flood->pkey, &my_public_key, sizeof (my_public_key)))
1044 update_network_size_estimate ();
1047 if (matching_bits >= ntohl (size_estimate_messages[idx].matching_bits))
1049 /* cancel transmission from us to this peer for this round */
1050 if (idx == estimate_index)
1052 if (peer_entry->previous_round == GNUNET_YES)
1054 /* cancel any activity for current round */
1055 if (peer_entry->transmit_task != GNUNET_SCHEDULER_NO_TASK)
1057 GNUNET_SCHEDULER_cancel (peer_entry->transmit_task);
1058 peer_entry->transmit_task = GNUNET_SCHEDULER_NO_TASK;
1060 if (peer_entry->th != NULL)
1062 GNUNET_CORE_notify_transmit_ready_cancel (peer_entry->th);
1063 peer_entry->th = NULL;
1069 /* cancel previous round only */
1070 peer_entry->previous_round = GNUNET_YES;
1073 if (matching_bits == ntohl (size_estimate_messages[idx].matching_bits))
1075 if (matching_bits <= ntohl (size_estimate_messages[idx].matching_bits))
1077 if ((idx < estimate_index) && (peer_entry->previous_round == GNUNET_YES))
1078 peer_entry->previous_round = GNUNET_NO;
1079 /* push back our result now, that peer is spreading bad information... */
1080 if (NULL == peer_entry->th)
1082 if (peer_entry->transmit_task != GNUNET_SCHEDULER_NO_TASK)
1083 GNUNET_SCHEDULER_cancel (peer_entry->transmit_task);
1084 peer_entry->transmit_task =
1085 GNUNET_SCHEDULER_add_now (&transmit_task, peer_entry);
1087 /* Not closer than our most recent message, no need to do work here */
1088 GNUNET_STATISTICS_update (stats,
1089 "# flood messages ignored (had closer already)",
1093 if (GNUNET_YES != verify_message_crypto (incoming_flood))
1095 GNUNET_break_op (0);
1098 size_estimate_messages[idx] = *incoming_flood;
1099 size_estimate_messages[idx].hop_count =
1100 htonl (ntohl (incoming_flood->hop_count) + 1);
1102 GNUNET_MAX (ntohl (incoming_flood->hop_count) + 1, hop_count_max);
1104 /* have a new, better size estimate, inform clients */
1105 update_network_size_estimate ();
1108 GNUNET_CONTAINER_multihashmap_iterate (peers, &update_flood_times,
1116 * Method called whenever a peer connects.
1118 * @param cls closure
1119 * @param peer peer identity this notification is about
1120 * @param atsi performance data
1121 * @param atsi_count number of records in 'atsi'
1124 handle_core_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
1125 const struct GNUNET_ATS_Information *atsi,
1126 unsigned int atsi_count)
1128 struct NSEPeerEntry *peer_entry;
1131 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Peer `%s' connected to us\n",
1134 peer_entry = GNUNET_malloc (sizeof (struct NSEPeerEntry));
1135 peer_entry->id = *peer;
1136 GNUNET_CONTAINER_multihashmap_put (peers, &peer->hashPubKey, peer_entry,
1137 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
1138 peer_entry->transmit_task =
1139 GNUNET_SCHEDULER_add_delayed (get_transmit_delay (-1), &transmit_task,
1145 * Method called whenever a peer disconnects.
1147 * @param cls closure
1148 * @param peer peer identity this notification is about
1151 handle_core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
1153 struct NSEPeerEntry *pos;
1156 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Peer `%s' disconnected from us\n",
1159 pos = GNUNET_CONTAINER_multihashmap_get (peers, &peer->hashPubKey);
1165 GNUNET_assert (GNUNET_YES ==
1166 GNUNET_CONTAINER_multihashmap_remove (peers, &peer->hashPubKey,
1168 if (pos->transmit_task != GNUNET_SCHEDULER_NO_TASK)
1169 GNUNET_SCHEDULER_cancel (pos->transmit_task);
1170 if (pos->th != NULL)
1172 GNUNET_CORE_notify_transmit_ready_cancel (pos->th);
1180 * Task run during shutdown.
1186 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1188 if (flood_task != GNUNET_SCHEDULER_NO_TASK)
1190 GNUNET_SCHEDULER_cancel (flood_task);
1191 flood_task = GNUNET_SCHEDULER_NO_TASK;
1193 if (proof_task != GNUNET_SCHEDULER_NO_TASK)
1195 GNUNET_SCHEDULER_cancel (proof_task);
1196 proof_task = GNUNET_SCHEDULER_NO_TASK;
1197 write_proof (); /* remember progress */
1201 GNUNET_SERVER_notification_context_destroy (nc);
1204 if (coreAPI != NULL)
1206 GNUNET_CORE_disconnect (coreAPI);
1211 GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
1216 GNUNET_CONTAINER_multihashmap_destroy (peers);
1219 if (my_private_key != NULL)
1221 GNUNET_CRYPTO_rsa_key_free (my_private_key);
1222 my_private_key = NULL;
1224 #if ENABLE_HISTOGRAM
1227 GNUNET_BIO_write_close (wh);
1235 * Called on core init/fail.
1237 * @param cls service closure
1238 * @param server handle to the server for this service
1239 * @param identity the public identity of this peer
1242 core_init (void *cls, struct GNUNET_CORE_Handle *server,
1243 const struct GNUNET_PeerIdentity *identity)
1245 struct GNUNET_TIME_Absolute now;
1246 struct GNUNET_TIME_Absolute prev_time;
1252 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connection to core FAILED!\n");
1254 GNUNET_SCHEDULER_shutdown ();
1258 memcmp (&my_identity, identity,
1259 sizeof (struct GNUNET_PeerIdentity)));
1260 now = GNUNET_TIME_absolute_get ();
1261 current_timestamp.abs_value =
1262 (now.abs_value / gnunet_nse_interval.rel_value) *
1263 gnunet_nse_interval.rel_value;
1264 next_timestamp.abs_value =
1265 current_timestamp.abs_value + gnunet_nse_interval.rel_value;
1267 for (i = 0; i < HISTORY_SIZE; i++)
1269 prev_time.abs_value =
1270 current_timestamp.abs_value - (HISTORY_SIZE - i -
1271 1) * gnunet_nse_interval.rel_value;
1272 setup_flood_message (i, prev_time);
1274 estimate_index = HISTORY_SIZE - 1;
1277 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
1278 (next_timestamp), &update_flood_message,
1284 * Handle network size estimate clients.
1286 * @param cls closure
1287 * @param server the initialized server
1288 * @param c configuration to use
1291 run (void *cls, struct GNUNET_SERVER_Handle *server,
1292 const struct GNUNET_CONFIGURATION_Handle *c)
1297 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
1298 {&handle_start_message, NULL, GNUNET_MESSAGE_TYPE_NSE_START,
1299 sizeof (struct GNUNET_MessageHeader)},
1302 static const struct GNUNET_CORE_MessageHandler core_handlers[] = {
1303 {&handle_p2p_size_estimate, GNUNET_MESSAGE_TYPE_NSE_P2P_FLOOD,
1304 sizeof (struct GNUNET_NSE_FloodMessage)},
1310 GNUNET_CONFIGURATION_get_value_time (cfg, "NSE", "INTERVAL",
1311 &gnunet_nse_interval)) ||
1313 GNUNET_CONFIGURATION_get_value_time (cfg, "NSE", "WORKDELAY",
1314 &proof_find_delay)) ||
1316 GNUNET_CONFIGURATION_get_value_number (cfg, "NSE", "WORKBITS",
1317 &nse_work_required)))
1319 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1321 ("NSE service is lacking key configuration settings. Exiting.\n"));
1322 GNUNET_SCHEDULER_shutdown ();
1325 if (nse_work_required >= sizeof (GNUNET_HashCode) * 8)
1327 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1328 _("Invalid work requirement for NSE service. Exiting.\n"));
1329 GNUNET_SCHEDULER_shutdown ();
1335 GNUNET_CONFIGURATION_get_value_filename (cfg, "GNUNETD", "HOSTKEY",
1338 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1340 ("NSE service is lacking key configuration settings. Exiting.\n"));
1341 GNUNET_SCHEDULER_shutdown ();
1344 my_private_key = GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
1345 GNUNET_free (keyfile);
1346 if (my_private_key == NULL)
1348 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1349 _("NSE service could not access hostkey. Exiting.\n"));
1350 GNUNET_SCHEDULER_shutdown ();
1353 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &my_public_key);
1354 GNUNET_CRYPTO_hash (&my_public_key, sizeof (my_public_key),
1355 &my_identity.hashPubKey);
1357 GNUNET_CONFIGURATION_get_value_filename (cfg, "NSE", "PROOFFILE", &proof))
1359 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1361 ("NSE service is lacking key configuration settings. Exiting.\n"));
1362 if (my_private_key != NULL)
1364 GNUNET_CRYPTO_rsa_key_free (my_private_key);
1365 my_private_key = NULL;
1367 GNUNET_SCHEDULER_shutdown ();
1370 if ((GNUNET_YES != GNUNET_DISK_file_test (proof)) ||
1371 (sizeof (my_proof) !=
1372 GNUNET_DISK_fn_read (proof, &my_proof, sizeof (my_proof))))
1374 GNUNET_free (proof);
1376 GNUNET_SCHEDULER_add_with_priority (GNUNET_SCHEDULER_PRIORITY_IDLE,
1379 peers = GNUNET_CONTAINER_multihashmap_create (128);
1380 GNUNET_SERVER_add_handlers (server, handlers);
1381 nc = GNUNET_SERVER_notification_context_create (server, 1);
1382 /* Connect to core service and register core handlers */
1383 coreAPI = GNUNET_CORE_connect (cfg, /* Main configuration */
1384 CORE_QUEUE_SIZE, /* queue size */
1385 NULL, /* Closure passed to functions */
1386 &core_init, /* Call core_init once connected */
1387 &handle_core_connect, /* Handle connects */
1388 &handle_core_disconnect, /* Handle disconnects */
1389 NULL, /* Don't want notified about all incoming messages */
1390 GNUNET_NO, /* For header only inbound notification */
1391 NULL, /* Don't want notified about all outbound messages */
1392 GNUNET_NO, /* For header only outbound notification */
1393 core_handlers); /* Register these handlers */
1394 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task,
1396 #if ENABLE_HISTOGRAM
1398 GNUNET_CONFIGURATION_get_value_filename (cfg, "NSE", "HISTOGRAM", &proof))
1400 wh = GNUNET_BIO_write_open (proof);
1401 GNUNET_free (proof);
1404 if (coreAPI == NULL)
1406 GNUNET_SCHEDULER_shutdown ();
1409 stats = GNUNET_STATISTICS_create ("nse", cfg);
1414 * The main function for the statistics service.
1416 * @param argc number of arguments from the command line
1417 * @param argv command line arguments
1418 * @return 0 ok, 1 on error
1421 main (int argc, char *const *argv)
1423 return (GNUNET_OK ==
1424 GNUNET_SERVICE_run (argc, argv, "nse", GNUNET_SERVICE_OPTION_NONE,
1425 &run, NULL)) ? 0 : 1;
1428 /* end of gnunet-service-nse.c */