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
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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.
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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.
39 #include "gnunet_util_lib.h"
40 #include "gnunet_constants.h"
41 #include "gnunet_protocols.h"
42 #include "gnunet_signatures.h"
43 #include "gnunet_statistics_service.h"
44 #include "gnunet_core_service.h"
45 #include "gnunet_nse_service.h"
49 * Should messages be delayed randomly? This option should be set to
50 * GNUNET_NO only for experiments, not in production. It should also
51 * be removed once the initial experiments have been completed.
53 #define USE_RANDOM_DELAYS GNUNET_YES
56 * Should we generate a histogram with the time stamps of when we received
57 * NSE messages to disk? (for performance evaluation only, not useful in
58 * production). The associated code should also probably be removed
59 * once we're done with experiments.
61 #define ENABLE_HISTOGRAM GNUNET_NO
64 * Over how many values do we calculate the weighted average?
66 #define HISTORY_SIZE 8
69 * Size of the queue to core.
71 #define CORE_QUEUE_SIZE 2
74 * Message priority to use.
76 #define NSE_PRIORITY 5
79 * Amount of work required (W-bit collisions) for NSE proofs, in collision-bits.
81 static unsigned long long nse_work_required;
84 * Interval for sending network size estimation flood requests.
86 static struct GNUNET_TIME_Relative gnunet_nse_interval;
89 * Interval between proof find runs.
91 static struct GNUNET_TIME_Relative proof_find_delay;
95 * Handle for writing when we received messages to disk.
97 static struct GNUNET_BIO_WriteHandle *wh;
102 * Per-peer information.
108 * Pending message for this peer.
110 struct GNUNET_MessageHeader *pending_message;
113 * Core handle for sending messages to this peer.
115 struct GNUNET_CORE_TransmitHandle *th;
118 * What is the identity of the peer?
120 struct GNUNET_PeerIdentity id;
123 * Task scheduled to send message to this peer.
125 GNUNET_SCHEDULER_TaskIdentifier transmit_task;
128 * Did we receive or send a message about the previous round
129 * to this peer yet? GNUNET_YES if the previous round has
130 * been taken care of.
137 * Network size estimate reply; sent when "this"
138 * peer's timer has run out before receiving a
139 * valid reply from another peer.
141 struct GNUNET_NSE_FloodMessage
144 * Type: GNUNET_MESSAGE_TYPE_NSE_P2P_FLOOD
146 struct GNUNET_MessageHeader header;
149 * Number of hops this message has taken so far.
151 uint32_t hop_count GNUNET_PACKED;
156 struct GNUNET_CRYPTO_RsaSignaturePurpose purpose;
159 * The current timestamp value (which all
160 * peers should agree on).
162 struct GNUNET_TIME_AbsoluteNBO timestamp;
165 * Number of matching bits between the hash
166 * of timestamp and the initiator's public
169 uint32_t matching_bits GNUNET_PACKED;
172 * Public key of the originator.
174 struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded pkey;
177 * Proof of work, causing leading zeros when hashed with pkey.
179 uint64_t proof_of_work GNUNET_PACKED;
182 * Signature (over range specified in purpose).
184 struct GNUNET_CRYPTO_RsaSignature signature;
189 * Handle to our current configuration.
191 static const struct GNUNET_CONFIGURATION_Handle *cfg;
194 * Handle to the statistics service.
196 static struct GNUNET_STATISTICS_Handle *stats;
199 * Handle to the core service.
201 static struct GNUNET_CORE_Handle *coreAPI;
204 * Map of all connected peers.
206 static struct GNUNET_CONTAINER_MultiHashMap *peers;
209 * The current network size estimate. Number of bits matching on
212 static double current_size_estimate;
215 * The standard deviation of the last HISTORY_SIZE network
218 static double current_std_dev = NAN;
221 * Current hop counter estimate (estimate for network diameter).
223 static uint32_t hop_count_max;
226 * Message for the next round, if we got any.
228 static struct GNUNET_NSE_FloodMessage next_message;
231 * Array of recent size estimate messages.
233 static struct GNUNET_NSE_FloodMessage size_estimate_messages[HISTORY_SIZE];
236 * Index of most recent estimate.
238 static unsigned int estimate_index;
241 * Number of valid entries in the history.
243 static unsigned int estimate_count;
246 * Task scheduled to update our flood message for the next round.
248 static GNUNET_SCHEDULER_TaskIdentifier flood_task;
251 * Task scheduled to compute our proof.
253 static GNUNET_SCHEDULER_TaskIdentifier proof_task;
256 * Notification context, simplifies client broadcasts.
258 static struct GNUNET_SERVER_NotificationContext *nc;
261 * The next major time.
263 static struct GNUNET_TIME_Absolute next_timestamp;
266 * The current major time.
268 static struct GNUNET_TIME_Absolute current_timestamp;
271 * The public key of this peer.
273 static struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded my_public_key;
276 * The private key of this peer.
278 static struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key;
281 * The peer identity of this peer.
283 static struct GNUNET_PeerIdentity my_identity;
286 * Proof of work for this peer.
288 static uint64_t my_proof;
292 * Initialize a message to clients with the current network
295 * @param em message to fill in
298 setup_estimate_message (struct GNUNET_NSE_ClientMessage *em)
313 /* Weighted incremental algorithm for stddev according to West (1979) */
317 for (i = 0; i < estimate_count; i++)
320 htonl (size_estimate_messages
321 [(estimate_index - i +
322 HISTORY_SIZE) % HISTORY_SIZE].matching_bits);
323 weight = 1; /* was: estimate_count + 1 - i; */
325 temp = weight + sumweight;
327 r = q * weight / temp;
328 sum += sumweight * q * r;
332 variance = sum / (sumweight - 1.0);
333 GNUNET_assert (variance >= 0);
334 std_dev = sqrt (variance);
335 current_std_dev = std_dev;
336 current_size_estimate = mean;
338 em->header.size = htons (sizeof (struct GNUNET_NSE_ClientMessage));
339 em->header.type = htons (GNUNET_MESSAGE_TYPE_NSE_ESTIMATE);
340 em->reserved = htonl (0);
341 em->timestamp = GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
342 em->size_estimate = mean - 0.332747;
343 nsize = log2 (GNUNET_CONTAINER_multihashmap_size (peers) + 1);
344 if (em->size_estimate < nsize)
345 em->size_estimate = nsize;
346 em->std_deviation = std_dev;
347 GNUNET_STATISTICS_set (stats, "# nodes in the network (estimate)",
348 (uint64_t) pow (2, mean - 1.0 / 3.0), GNUNET_NO);
353 * Handler for START message from client, triggers an
354 * immediate current network estimate notification.
355 * Also, we remember the client for updates upon future
356 * estimate measurements.
359 * @param client who sent the message
360 * @param message the message received
363 handle_start_message (void *cls, struct GNUNET_SERVER_Client *client,
364 const struct GNUNET_MessageHeader *message)
366 struct GNUNET_NSE_ClientMessage em;
369 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received START message from client\n");
371 GNUNET_SERVER_notification_context_add (nc, client);
372 setup_estimate_message (&em);
373 GNUNET_SERVER_notification_context_unicast (nc, client, &em.header,
375 GNUNET_SERVER_receive_done (client, GNUNET_OK);
380 * How long should we delay a message to go the given number of
383 * @param matching_bits number of matching bits to consider
386 get_matching_bits_delay (uint32_t matching_bits)
388 /* Calculated as: S + f/2 - (f / pi) * (atan(x - p')) */
389 // S is next_timestamp (ignored in return value)
390 // f is frequency (gnunet_nse_interval)
391 // x is matching_bits
392 // p' is current_size_estimate
393 return ((double) gnunet_nse_interval.rel_value / (double) 2.0) -
394 ((gnunet_nse_interval.rel_value / M_PI) *
395 atan (matching_bits - current_size_estimate));
400 * What delay randomization should we apply for a given number of matching bits?
402 * @param matching_bits number of matching bits
403 * @return random delay to apply
405 static struct GNUNET_TIME_Relative
406 get_delay_randomization (uint32_t matching_bits)
408 #if USE_RANDOM_DELAYS
409 struct GNUNET_TIME_Relative ret;
411 if (matching_bits == 0)
412 return GNUNET_TIME_UNIT_ZERO;
414 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
415 (uint32_t) (get_matching_bits_delay
417 1) / (double) (hop_count_max +
421 return GNUNET_TIME_UNIT_ZERO;
427 * Get the number of matching bits that the given timestamp has to the given peer ID.
429 * @param timestamp time to generate key
430 * @param id peer identity to compare with
431 * @return number of matching bits
434 get_matching_bits (struct GNUNET_TIME_Absolute timestamp,
435 const struct GNUNET_PeerIdentity *id)
437 GNUNET_HashCode timestamp_hash;
439 GNUNET_CRYPTO_hash (×tamp.abs_value, sizeof (timestamp.abs_value),
441 return GNUNET_CRYPTO_hash_matching_bits (×tamp_hash, &id->hashPubKey);
446 * Get the transmission delay that should be applied for a
449 * @param round_offset -1 for the previous round (random delay between 0 and 50ms)
450 * 0 for the current round (based on our proximity to time key)
451 * @return delay that should be applied
453 static struct GNUNET_TIME_Relative
454 get_transmit_delay (int round_offset)
456 struct GNUNET_TIME_Relative ret;
457 struct GNUNET_TIME_Absolute tgt;
459 uint32_t matching_bits;
461 switch (round_offset)
464 /* previous round is randomized between 0 and 50 ms */
465 #if USE_RANDOM_DELAYS
466 ret.rel_value = GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, 50);
468 ret = GNUNET_TIME_UNIT_ZERO;
471 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
472 "Transmitting previous round behind schedule in %llu ms\n",
473 (unsigned long long) ret.rel_value);
477 /* current round is based on best-known matching_bits */
479 ntohl (size_estimate_messages[estimate_index].matching_bits);
480 dist_delay = get_matching_bits_delay (matching_bits);
481 dist_delay += get_delay_randomization (matching_bits).rel_value;
482 ret.rel_value = (uint64_t) dist_delay;
484 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
485 "For round %llu, delay for %u matching bits is %llu ms\n",
486 (unsigned long long) current_timestamp.abs_value,
487 (unsigned int) matching_bits,
488 (unsigned long long) ret.rel_value);
490 /* now consider round start time and add delay to it */
491 tgt = GNUNET_TIME_absolute_add (current_timestamp, ret);
492 return GNUNET_TIME_absolute_get_remaining (tgt);
495 return GNUNET_TIME_UNIT_FOREVER_REL;
500 * Task that triggers a NSE P2P transmission.
502 * @param cls the 'struct NSEPeerEntry'
503 * @param tc scheduler context
506 transmit_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
510 * Called when core is ready to send a message we asked for
511 * out to the destination.
513 * @param cls closure (NULL)
514 * @param size number of bytes available in buf
515 * @param buf where the callee should write the message
516 * @return number of bytes written to buf
519 transmit_ready (void *cls, size_t size, void *buf)
521 struct NSEPeerEntry *peer_entry = cls;
524 peer_entry->th = NULL;
527 /* client disconnected */
530 GNUNET_assert (size >= sizeof (struct GNUNET_NSE_FloodMessage));
531 idx = estimate_index;
532 if (peer_entry->previous_round == GNUNET_NO)
534 idx = (idx + HISTORY_SIZE - 1) % HISTORY_SIZE;
535 peer_entry->previous_round = GNUNET_YES;
536 peer_entry->transmit_task =
537 GNUNET_SCHEDULER_add_delayed (get_transmit_delay (0), &transmit_task,
540 if ((ntohl (size_estimate_messages[idx].hop_count) == 0) &&
541 (GNUNET_SCHEDULER_NO_TASK != proof_task))
543 GNUNET_STATISTICS_update (stats,
544 "# flood messages not generated (no proof yet)",
549 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
550 "In round %llu, sending to `%s' estimate with %u bits\n",
552 GNUNET_TIME_absolute_ntoh (size_estimate_messages[idx].
553 timestamp).abs_value,
554 GNUNET_i2s (&peer_entry->id),
555 (unsigned int) ntohl (size_estimate_messages[idx].matching_bits));
557 if (ntohl (size_estimate_messages[idx].hop_count) == 0)
558 GNUNET_STATISTICS_update (stats, "# flood messages started", 1, GNUNET_NO);
559 GNUNET_STATISTICS_update (stats, "# flood messages transmitted", 1,
561 memcpy (buf, &size_estimate_messages[idx],
562 sizeof (struct GNUNET_NSE_FloodMessage));
563 GNUNET_STATISTICS_update (stats, "# flood messages sent", 1, GNUNET_NO);
564 return sizeof (struct GNUNET_NSE_FloodMessage);
569 * Task that triggers a NSE P2P transmission.
571 * @param cls the 'struct NSEPeerEntry'
572 * @param tc scheduler context
575 transmit_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
577 struct NSEPeerEntry *peer_entry = cls;
579 peer_entry->transmit_task = GNUNET_SCHEDULER_NO_TASK;
580 GNUNET_assert (NULL == peer_entry->th);
582 GNUNET_CORE_notify_transmit_ready (coreAPI, GNUNET_NO, NSE_PRIORITY,
583 GNUNET_TIME_UNIT_FOREVER_REL,
586 GNUNET_NSE_FloodMessage),
587 &transmit_ready, peer_entry);
592 * We've sent on our flood message or one that we received which was
593 * validated and closer than ours. Update the global list of recent
594 * messages and the average. Also re-broadcast the message to any
598 update_network_size_estimate ()
600 struct GNUNET_NSE_ClientMessage em;
602 setup_estimate_message (&em);
603 GNUNET_SERVER_notification_context_broadcast (nc, &em.header, GNUNET_YES);
608 * Setup a flood message in our history array at the given
609 * slot offset for the given timestamp.
611 * @param slot index to use
612 * @param ts timestamp to use
615 setup_flood_message (unsigned int slot, struct GNUNET_TIME_Absolute ts)
617 struct GNUNET_NSE_FloodMessage *fm;
618 uint32_t matching_bits;
620 matching_bits = get_matching_bits (ts, &my_identity);
621 fm = &size_estimate_messages[slot];
622 fm->header.size = htons (sizeof (struct GNUNET_NSE_FloodMessage));
623 fm->header.type = htons (GNUNET_MESSAGE_TYPE_NSE_P2P_FLOOD);
624 fm->hop_count = htonl (0);
625 fm->purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_NSE_SEND);
627 htonl (sizeof (struct GNUNET_NSE_FloodMessage) -
628 sizeof (struct GNUNET_MessageHeader) - sizeof (uint32_t) -
629 sizeof (struct GNUNET_CRYPTO_RsaSignature));
630 fm->matching_bits = htonl (matching_bits);
631 fm->timestamp = GNUNET_TIME_absolute_hton (ts);
632 fm->pkey = my_public_key;
633 fm->proof_of_work = my_proof;
634 GNUNET_assert (GNUNET_OK ==
635 GNUNET_CRYPTO_rsa_sign (my_private_key, &fm->purpose, &fm->signature));
640 * Schedule transmission for the given peer for the current round based
641 * on what we know about the desired delay.
644 * @param key hash of peer identity
645 * @param value the 'struct NSEPeerEntry'
646 * @return GNUNET_OK (continue to iterate)
649 schedule_current_round (void *cls, const GNUNET_HashCode * key, void *value)
651 struct NSEPeerEntry *peer_entry = value;
652 struct GNUNET_TIME_Relative delay;
654 if (peer_entry->th != NULL)
656 peer_entry->previous_round = GNUNET_NO;
659 if (peer_entry->transmit_task != GNUNET_SCHEDULER_NO_TASK)
661 GNUNET_SCHEDULER_cancel (peer_entry->transmit_task);
662 peer_entry->previous_round = GNUNET_NO;
665 get_transmit_delay ((peer_entry->previous_round == GNUNET_NO) ? -1 : 0);
666 peer_entry->transmit_task =
667 GNUNET_SCHEDULER_add_delayed (delay, &transmit_task, peer_entry);
673 * Update our flood message to be sent (and our timestamps).
676 * @param tc context for this message
679 update_flood_message (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
681 struct GNUNET_TIME_Relative offset;
684 flood_task = GNUNET_SCHEDULER_NO_TASK;
685 offset = GNUNET_TIME_absolute_get_remaining (next_timestamp);
686 if (0 != offset.rel_value)
688 /* somehow run early, delay more */
690 GNUNET_SCHEDULER_add_delayed (offset, &update_flood_message, NULL);
693 current_timestamp = next_timestamp;
695 GNUNET_TIME_absolute_add (current_timestamp, gnunet_nse_interval);
696 estimate_index = (estimate_index + 1) % HISTORY_SIZE;
697 if (estimate_count < HISTORY_SIZE)
699 if (next_timestamp.abs_value ==
700 GNUNET_TIME_absolute_ntoh (next_message.timestamp).abs_value)
702 /* we received a message for this round way early, use it! */
703 size_estimate_messages[estimate_index] = next_message;
704 size_estimate_messages[estimate_index].hop_count =
705 htonl (1 + ntohl (next_message.hop_count));
708 setup_flood_message (estimate_index, current_timestamp);
709 next_message.matching_bits = htonl (0); /* reset for 'next' round */
711 for (i = 0; i < HISTORY_SIZE; i++)
713 GNUNET_MAX (ntohl (size_estimate_messages[i].hop_count), hop_count_max);
714 GNUNET_CONTAINER_multihashmap_iterate (peers, &schedule_current_round, NULL);
716 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
717 (next_timestamp), &update_flood_message,
723 * Count the leading zeroes in hash.
726 * @return the number of leading zero bits.
729 count_leading_zeroes (const GNUNET_HashCode * hash)
731 unsigned int hash_count;
734 while ((0 == GNUNET_CRYPTO_hash_get_bit (hash, hash_count)))
741 * Check whether the given public key
742 * and integer are a valid proof of work.
744 * @param pkey the public key
745 * @param val the integer
747 * @return GNUNET_YES if valid, GNUNET_NO if not
750 check_proof_of_work (const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *pkey,
753 char buf[sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded) +
755 GNUNET_HashCode result;
757 memcpy (buf, &val, sizeof (val));
758 memcpy (&buf[sizeof (val)], pkey,
759 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
760 GNUNET_CRYPTO_hash (buf, sizeof (buf), &result);
761 return (count_leading_zeroes (&result) >=
762 nse_work_required) ? GNUNET_YES : GNUNET_NO;
767 * Write our current proof to disk.
775 GNUNET_CONFIGURATION_get_value_filename (cfg, "NSE", "PROOFFILE", &proof))
777 if (sizeof (my_proof) !=
778 GNUNET_DISK_fn_write (proof, &my_proof, sizeof (my_proof),
779 GNUNET_DISK_PERM_USER_READ |
780 GNUNET_DISK_PERM_USER_WRITE))
781 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "write", proof);
788 * Find our proof of work.
790 * @param cls closure (unused)
791 * @param tc task context
794 find_proof (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
796 #define ROUND_SIZE 10
798 char buf[sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded) +
800 GNUNET_HashCode result;
803 proof_task = GNUNET_SCHEDULER_NO_TASK;
804 memcpy (&buf[sizeof (uint64_t)], &my_public_key,
805 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
808 while ((counter != UINT64_MAX) && (i < ROUND_SIZE))
810 memcpy (buf, &counter, sizeof (uint64_t));
811 GNUNET_CRYPTO_hash (buf, sizeof (buf), &result);
812 if (nse_work_required <= count_leading_zeroes (&result))
816 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Proof of work found: %llu!\n",
817 (unsigned long long) GNUNET_ntohll (counter));
819 for (i = 0; i < HISTORY_SIZE; i++)
820 if (ntohl (size_estimate_messages[i].hop_count) == 0)
822 size_estimate_messages[i].proof_of_work = my_proof;
823 GNUNET_assert (GNUNET_OK ==
824 GNUNET_CRYPTO_rsa_sign (my_private_key,
825 &size_estimate_messages[i].purpose,
826 &size_estimate_messages[i].signature));
834 if (my_proof / (100 * ROUND_SIZE) < counter / (100 * ROUND_SIZE))
837 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Testing proofs currently at %llu\n",
838 (unsigned long long) counter);
840 /* remember progress every 100 rounds */
849 GNUNET_SCHEDULER_add_delayed (proof_find_delay, &find_proof, NULL);
854 * An incoming flood message has been received which claims
855 * to have more bits matching than any we know in this time
856 * period. Verify the signature and/or proof of work.
858 * @param incoming_flood the message to verify
860 * @return GNUNET_YES if the message is verified
861 * GNUNET_NO if the key/signature don't verify
864 verify_message_crypto (const struct GNUNET_NSE_FloodMessage *incoming_flood)
867 check_proof_of_work (&incoming_flood->pkey,
868 incoming_flood->proof_of_work))
870 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Proof of work invalid: %llu!\n"),
872 GNUNET_ntohll (incoming_flood->proof_of_work));
877 GNUNET_CRYPTO_rsa_verify (GNUNET_SIGNATURE_PURPOSE_NSE_SEND,
878 &incoming_flood->purpose,
879 &incoming_flood->signature,
880 &incoming_flood->pkey))
890 * Update transmissions for the given peer for the current round based
891 * on updated proximity information.
893 * @param cls peer entry to exclude from updates
894 * @param key hash of peer identity
895 * @param value the 'struct NSEPeerEntry'
896 * @return GNUNET_OK (continue to iterate)
899 update_flood_times (void *cls, const GNUNET_HashCode * key, void *value)
901 struct NSEPeerEntry *exclude = cls;
902 struct NSEPeerEntry *peer_entry = value;
903 struct GNUNET_TIME_Relative delay;
905 if (peer_entry->th != NULL)
906 return GNUNET_OK; /* already active */
907 if (peer_entry == exclude)
908 return GNUNET_OK; /* trigger of the update */
909 if (peer_entry->previous_round == GNUNET_NO)
911 /* still stuck in previous round, no point to update, check that
912 * we are active here though... */
913 GNUNET_break ((peer_entry->transmit_task != GNUNET_SCHEDULER_NO_TASK) ||
914 (peer_entry->th != NULL));
917 if (peer_entry->transmit_task != GNUNET_SCHEDULER_NO_TASK)
919 GNUNET_SCHEDULER_cancel (peer_entry->transmit_task);
920 peer_entry->transmit_task = GNUNET_SCHEDULER_NO_TASK;
922 delay = get_transmit_delay (0);
923 peer_entry->transmit_task =
924 GNUNET_SCHEDULER_add_delayed (delay, &transmit_task, peer_entry);
930 * Core handler for size estimate flooding messages.
932 * @param cls closure unused
933 * @param message message
934 * @param peer peer identity this message is from (ignored)
935 * @param atsi performance data (ignored)
939 handle_p2p_size_estimate (void *cls, const struct GNUNET_PeerIdentity *peer,
940 const struct GNUNET_MessageHeader *message,
941 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
943 const struct GNUNET_NSE_FloodMessage *incoming_flood;
944 struct GNUNET_TIME_Absolute ts;
945 struct NSEPeerEntry *peer_entry;
946 uint32_t matching_bits;
951 GNUNET_BIO_write_int64 (wh, GNUNET_TIME_absolute_get ().abs_value);
953 incoming_flood = (const struct GNUNET_NSE_FloodMessage *) message;
954 GNUNET_STATISTICS_update (stats, "# flood messages received", 1, GNUNET_NO);
955 matching_bits = ntohl (incoming_flood->matching_bits);
960 struct GNUNET_PeerIdentity os;
962 GNUNET_CRYPTO_hash (&incoming_flood->pkey,
963 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
965 GNUNET_snprintf (origin, sizeof (origin), "%s", GNUNET_i2s (&os));
966 GNUNET_snprintf (pred, sizeof (pred), "%s", GNUNET_i2s (peer));
967 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
968 "Flood at %llu from `%s' via `%s' at `%s' with bits %u\n",
970 GNUNET_TIME_absolute_ntoh (incoming_flood->timestamp).abs_value,
971 origin, pred, GNUNET_i2s (&my_identity),
972 (unsigned int) matching_bits);
976 peer_entry = GNUNET_CONTAINER_multihashmap_get (peers, &peer->hashPubKey);
977 if (NULL == peer_entry)
983 ts = GNUNET_TIME_absolute_ntoh (incoming_flood->timestamp);
985 if (ts.abs_value == current_timestamp.abs_value)
986 idx = estimate_index;
987 else if (ts.abs_value ==
988 current_timestamp.abs_value - gnunet_nse_interval.rel_value)
989 idx = (estimate_index + HISTORY_SIZE - 1) % HISTORY_SIZE;
990 else if (ts.abs_value ==
991 next_timestamp.abs_value - gnunet_nse_interval.rel_value)
993 if (matching_bits <= ntohl (next_message.matching_bits))
994 return GNUNET_OK; /* ignore, simply too early/late */
995 if (GNUNET_YES != verify_message_crypto (incoming_flood))
1000 next_message = *incoming_flood;
1005 GNUNET_STATISTICS_update (stats,
1006 "# flood messages discarded (clock skew too large)",
1010 if (0 == (memcmp (peer, &my_identity, sizeof (struct GNUNET_PeerIdentity))))
1012 /* send to self, update our own estimate IF this also comes from us! */
1014 memcmp (&incoming_flood->pkey, &my_public_key, sizeof (my_public_key)))
1015 update_network_size_estimate ();
1018 if (matching_bits >= ntohl (size_estimate_messages[idx].matching_bits))
1020 /* cancel transmission from us to this peer for this round */
1021 if (idx == estimate_index)
1023 if (peer_entry->previous_round == GNUNET_YES)
1025 /* cancel any activity for current round */
1026 if (peer_entry->transmit_task != GNUNET_SCHEDULER_NO_TASK)
1028 GNUNET_SCHEDULER_cancel (peer_entry->transmit_task);
1029 peer_entry->transmit_task = GNUNET_SCHEDULER_NO_TASK;
1031 if (peer_entry->th != NULL)
1033 GNUNET_CORE_notify_transmit_ready_cancel (peer_entry->th);
1034 peer_entry->th = NULL;
1040 /* cancel previous round only */
1041 peer_entry->previous_round = GNUNET_YES;
1044 if (matching_bits == ntohl (size_estimate_messages[idx].matching_bits))
1046 if (matching_bits <= ntohl (size_estimate_messages[idx].matching_bits))
1048 if ((idx < estimate_index) && (peer_entry->previous_round == GNUNET_YES))
1049 peer_entry->previous_round = GNUNET_NO;
1050 /* push back our result now, that peer is spreading bad information... */
1051 if (NULL == peer_entry->th)
1053 if (peer_entry->transmit_task != GNUNET_SCHEDULER_NO_TASK)
1054 GNUNET_SCHEDULER_cancel (peer_entry->transmit_task);
1055 peer_entry->transmit_task =
1056 GNUNET_SCHEDULER_add_now (&transmit_task, peer_entry);
1058 /* Not closer than our most recent message, no need to do work here */
1059 GNUNET_STATISTICS_update (stats,
1060 "# flood messages ignored (had closer already)",
1064 if (GNUNET_YES != verify_message_crypto (incoming_flood))
1066 GNUNET_break_op (0);
1069 size_estimate_messages[idx] = *incoming_flood;
1070 size_estimate_messages[idx].hop_count =
1071 htonl (ntohl (incoming_flood->hop_count) + 1);
1073 GNUNET_MAX (ntohl (incoming_flood->hop_count) + 1, hop_count_max);
1075 /* have a new, better size estimate, inform clients */
1076 update_network_size_estimate ();
1079 GNUNET_CONTAINER_multihashmap_iterate (peers, &update_flood_times,
1087 * Method called whenever a peer connects.
1089 * @param cls closure
1090 * @param peer peer identity this notification is about
1091 * @param atsi performance data
1094 handle_core_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
1095 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
1097 struct NSEPeerEntry *peer_entry;
1100 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Peer `%s' connected to us\n",
1103 peer_entry = GNUNET_malloc (sizeof (struct NSEPeerEntry));
1104 peer_entry->id = *peer;
1105 GNUNET_CONTAINER_multihashmap_put (peers, &peer->hashPubKey, peer_entry,
1106 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
1107 peer_entry->transmit_task =
1108 GNUNET_SCHEDULER_add_delayed (get_transmit_delay (-1), &transmit_task,
1114 * Method called whenever a peer disconnects.
1116 * @param cls closure
1117 * @param peer peer identity this notification is about
1120 handle_core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
1122 struct NSEPeerEntry *pos;
1125 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Peer `%s' disconnected from us\n",
1128 pos = GNUNET_CONTAINER_multihashmap_get (peers, &peer->hashPubKey);
1134 GNUNET_assert (GNUNET_YES ==
1135 GNUNET_CONTAINER_multihashmap_remove (peers, &peer->hashPubKey,
1137 if (pos->transmit_task != GNUNET_SCHEDULER_NO_TASK)
1138 GNUNET_SCHEDULER_cancel (pos->transmit_task);
1139 if (pos->th != NULL)
1141 GNUNET_CORE_notify_transmit_ready_cancel (pos->th);
1149 * Task run during shutdown.
1155 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1157 if (flood_task != GNUNET_SCHEDULER_NO_TASK)
1159 GNUNET_SCHEDULER_cancel (flood_task);
1160 flood_task = GNUNET_SCHEDULER_NO_TASK;
1162 if (proof_task != GNUNET_SCHEDULER_NO_TASK)
1164 GNUNET_SCHEDULER_cancel (proof_task);
1165 proof_task = GNUNET_SCHEDULER_NO_TASK;
1166 write_proof (); /* remember progress */
1170 GNUNET_SERVER_notification_context_destroy (nc);
1173 if (coreAPI != NULL)
1175 GNUNET_CORE_disconnect (coreAPI);
1180 GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
1185 GNUNET_CONTAINER_multihashmap_destroy (peers);
1188 if (my_private_key != NULL)
1190 GNUNET_CRYPTO_rsa_key_free (my_private_key);
1191 my_private_key = NULL;
1193 #if ENABLE_HISTOGRAM
1196 GNUNET_BIO_write_close (wh);
1204 * Called on core init/fail.
1206 * @param cls service closure
1207 * @param server handle to the server for this service
1208 * @param identity the public identity of this peer
1209 * @param publicKey the public key of this peer
1212 core_init (void *cls, struct GNUNET_CORE_Handle *server,
1213 const struct GNUNET_PeerIdentity *identity,
1214 const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *publicKey)
1216 struct GNUNET_TIME_Absolute now;
1217 struct GNUNET_TIME_Absolute prev_time;
1223 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connection to core FAILED!\n");
1225 GNUNET_SCHEDULER_shutdown ();
1229 memcmp (&my_identity, identity,
1230 sizeof (struct GNUNET_PeerIdentity)));
1231 now = GNUNET_TIME_absolute_get ();
1232 current_timestamp.abs_value =
1233 (now.abs_value / gnunet_nse_interval.rel_value) *
1234 gnunet_nse_interval.rel_value;
1235 next_timestamp.abs_value =
1236 current_timestamp.abs_value + gnunet_nse_interval.rel_value;
1238 for (i = 0; i < HISTORY_SIZE; i++)
1240 prev_time.abs_value =
1241 current_timestamp.abs_value - (HISTORY_SIZE - i -
1242 1) * gnunet_nse_interval.rel_value;
1243 setup_flood_message (i, prev_time);
1245 estimate_index = HISTORY_SIZE - 1;
1248 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
1249 (next_timestamp), &update_flood_message,
1255 * Handle network size estimate clients.
1257 * @param cls closure
1258 * @param server the initialized server
1259 * @param c configuration to use
1262 run (void *cls, struct GNUNET_SERVER_Handle *server,
1263 const struct GNUNET_CONFIGURATION_Handle *c)
1268 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
1269 {&handle_start_message, NULL, GNUNET_MESSAGE_TYPE_NSE_START,
1270 sizeof (struct GNUNET_MessageHeader)},
1273 static const struct GNUNET_CORE_MessageHandler core_handlers[] = {
1274 {&handle_p2p_size_estimate, GNUNET_MESSAGE_TYPE_NSE_P2P_FLOOD,
1275 sizeof (struct GNUNET_NSE_FloodMessage)},
1281 GNUNET_CONFIGURATION_get_value_time (cfg, "NSE", "INTERVAL",
1282 &gnunet_nse_interval)) ||
1284 GNUNET_CONFIGURATION_get_value_time (cfg, "NSE", "WORKDELAY",
1285 &proof_find_delay)) ||
1287 GNUNET_CONFIGURATION_get_value_number (cfg, "NSE", "WORKBITS",
1288 &nse_work_required)))
1290 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1292 ("NSE service is lacking key configuration settings. Exiting.\n"));
1293 GNUNET_SCHEDULER_shutdown ();
1296 if (nse_work_required >= sizeof (GNUNET_HashCode) * 8)
1298 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1299 _("Invalid work requirement for NSE service. Exiting.\n"));
1300 GNUNET_SCHEDULER_shutdown ();
1306 GNUNET_CONFIGURATION_get_value_filename (cfg, "GNUNETD", "HOSTKEY",
1309 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1311 ("NSE service is lacking key configuration settings. Exiting.\n"));
1312 GNUNET_SCHEDULER_shutdown ();
1315 my_private_key = GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
1316 GNUNET_free (keyfile);
1317 if (my_private_key == NULL)
1319 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1320 _("NSE service could not access hostkey. Exiting.\n"));
1321 GNUNET_SCHEDULER_shutdown ();
1324 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &my_public_key);
1325 GNUNET_CRYPTO_hash (&my_public_key, sizeof (my_public_key),
1326 &my_identity.hashPubKey);
1328 GNUNET_CONFIGURATION_get_value_filename (cfg, "NSE", "PROOFFILE", &proof))
1330 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1332 ("NSE service is lacking key configuration settings. Exiting.\n"));
1333 if (my_private_key != NULL)
1335 GNUNET_CRYPTO_rsa_key_free (my_private_key);
1336 my_private_key = NULL;
1338 GNUNET_SCHEDULER_shutdown ();
1341 if ((GNUNET_YES != GNUNET_DISK_file_test (proof)) ||
1342 (sizeof (my_proof) !=
1343 GNUNET_DISK_fn_read (proof, &my_proof, sizeof (my_proof))))
1345 GNUNET_free (proof);
1347 GNUNET_SCHEDULER_add_with_priority (GNUNET_SCHEDULER_PRIORITY_IDLE,
1350 peers = GNUNET_CONTAINER_multihashmap_create (128);
1351 GNUNET_SERVER_add_handlers (server, handlers);
1352 nc = GNUNET_SERVER_notification_context_create (server, 1);
1353 /* Connect to core service and register core handlers */
1354 coreAPI = GNUNET_CORE_connect (cfg, /* Main configuration */
1355 CORE_QUEUE_SIZE, /* queue size */
1356 NULL, /* Closure passed to functions */
1357 &core_init, /* Call core_init once connected */
1358 &handle_core_connect, /* Handle connects */
1359 &handle_core_disconnect, /* Handle disconnects */
1360 NULL, /* Do we care about "status" updates? */
1361 NULL, /* Don't want notified about all incoming messages */
1362 GNUNET_NO, /* For header only inbound notification */
1363 NULL, /* Don't want notified about all outbound messages */
1364 GNUNET_NO, /* For header only outbound notification */
1365 core_handlers); /* Register these handlers */
1366 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task,
1368 #if ENABLE_HISTOGRAM
1370 GNUNET_CONFIGURATION_get_value_filename (cfg, "NSE", "HISTOGRAM", &proof))
1372 wh = GNUNET_BIO_write_open (proof);
1373 GNUNET_free (proof);
1376 if (coreAPI == NULL)
1378 GNUNET_SCHEDULER_shutdown ();
1381 stats = GNUNET_STATISTICS_create ("nse", cfg);
1386 * The main function for the statistics service.
1388 * @param argc number of arguments from the command line
1389 * @param argv command line arguments
1390 * @return 0 ok, 1 on error
1393 main (int argc, char *const *argv)
1395 return (GNUNET_OK ==
1396 GNUNET_SERVICE_run (argc, argv, "nse", GNUNET_SERVICE_OPTION_NONE,
1397 &run, NULL)) ? 0 : 1;
1400 /* end of gnunet-service-nse.c */