2 This file is part of GNUnet.
3 (C) 2009 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 2, 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.
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file core/gnunet-service-core.c
23 * @brief high-level P2P messaging
24 * @author Christian Grothoff
26 * Considerations for later:
27 * - check that hostkey used by transport (for HELLOs) is the
28 * same as the hostkey that we are using!
29 * - add code to send PINGs if we are about to time-out otherwise
30 * - optimize lookup (many O(n) list traversals
31 * could ideally be changed to O(1) hash map lookups)
34 #include "gnunet_constants.h"
35 #include "gnunet_util_lib.h"
36 #include "gnunet_hello_lib.h"
37 #include "gnunet_peerinfo_service.h"
38 #include "gnunet_protocols.h"
39 #include "gnunet_signatures.h"
40 #include "gnunet_transport_service.h"
44 #define DEBUG_HANDSHAKE GNUNET_NO
47 * Receive and send buffer windows grow over time. For
48 * how long can 'unused' bandwidth accumulate before we
49 * need to cap it? (specified in ms).
51 #define MAX_WINDOW_TIME (5 * 60 * 1000)
54 * How many messages do we queue up at most for optional
55 * notifications to a client? (this can cause notifications
56 * about outgoing messages to be dropped).
58 #define MAX_NOTIFY_QUEUE 16
61 * Minimum of bytes per minute (out) to assign to any connected peer.
62 * Should be rather low; values larger than DEFAULT_BPM_IN_OUT make no
65 #define MIN_BPM_PER_PEER GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT
68 * What is the smallest change (in number of bytes per minute)
69 * that we consider significant enough to bother triggering?
71 #define MIN_BPM_CHANGE 32
74 * After how much time past the "official" expiration time do
75 * we discard messages? Should not be zero since we may
76 * intentionally defer transmission until close to the deadline
77 * and then may be slightly past the deadline due to inaccuracy
78 * in sleep and our own CPU consumption.
80 #define PAST_EXPIRATION_DISCARD_TIME GNUNET_TIME_UNIT_SECONDS
83 * What is the maximum delay for a SET_KEY message?
85 #define MAX_SET_KEY_DELAY GNUNET_TIME_UNIT_SECONDS
88 * What how long do we wait for SET_KEY confirmation initially?
90 #define INITIAL_SET_KEY_RETRY_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 3)
93 * What is the maximum delay for a PING message?
95 #define MAX_PING_DELAY GNUNET_TIME_UNIT_SECONDS
98 * What is the maximum delay for a PONG message?
100 #define MAX_PONG_DELAY GNUNET_TIME_UNIT_SECONDS
103 * How often do we recalculate bandwidth quotas?
105 #define QUOTA_UPDATE_FREQUENCY GNUNET_TIME_UNIT_SECONDS
108 * What is the priority for a SET_KEY message?
110 #define SET_KEY_PRIORITY 0xFFFFFF
113 * What is the priority for a PING message?
115 #define PING_PRIORITY 0xFFFFFF
118 * What is the priority for a PONG message?
120 #define PONG_PRIORITY 0xFFFFFF
123 * How many messages do we queue per peer at most?
125 #define MAX_PEER_QUEUE_SIZE 16
128 * How many non-mandatory messages do we queue per client at most?
130 #define MAX_CLIENT_QUEUE_SIZE 32
133 * What is the maximum age of a message for us to consider
134 * processing it? Note that this looks at the timestamp used
135 * by the other peer, so clock skew between machines does
136 * come into play here. So this should be picked high enough
137 * so that a little bit of clock skew does not prevent peers
138 * from connecting to us.
140 #define MAX_MESSAGE_AGE GNUNET_TIME_UNIT_DAYS
143 * What is the maximum size for encrypted messages? Note that this
144 * number imposes a clear limit on the maximum size of any message.
145 * Set to a value close to 64k but not so close that transports will
146 * have trouble with their headers.
148 #define MAX_ENCRYPTED_MESSAGE_SIZE (63 * 1024)
152 * State machine for our P2P encryption handshake. Everyone starts in
153 * "DOWN", if we receive the other peer's key (other peer initiated)
154 * we start in state RECEIVED (since we will immediately send our
155 * own); otherwise we start in SENT. If we get back a PONG from
156 * within either state, we move up to CONFIRMED (the PONG will always
157 * be sent back encrypted with the key we sent to the other peer).
159 enum PeerStateMachine
163 PEER_STATE_KEY_RECEIVED,
164 PEER_STATE_KEY_CONFIRMED
169 * Number of bytes (at the beginning) of "struct EncryptedMessage"
170 * that are NOT encrypted.
172 #define ENCRYPTED_HEADER_SIZE (sizeof(struct GNUNET_MessageHeader) + sizeof(uint32_t))
176 * Encapsulation for encrypted messages exchanged between
177 * peers. Followed by the actual encrypted data.
179 struct EncryptedMessage
182 * Message type is either CORE_ENCRYPTED_MESSAGE.
184 struct GNUNET_MessageHeader header;
187 * Random value used for IV generation. ENCRYPTED_HEADER_SIZE must
188 * be set to the offset of the *next* field.
190 uint32_t iv_seed GNUNET_PACKED;
193 * Hash of the plaintext (starting at 'sequence_number'), used to
194 * verify message integrity. Everything after this hash (including
195 * this hash itself) will be encrypted.
197 GNUNET_HashCode plaintext_hash;
200 * Sequence number, in network byte order. This field
201 * must be the first encrypted/decrypted field and the
202 * first byte that is hashed for the plaintext hash.
204 uint32_t sequence_number GNUNET_PACKED;
207 * Desired bandwidth (how much we should send to this
208 * peer / how much is the sender willing to receive),
209 * in bytes per minute.
211 uint32_t inbound_bpm_limit GNUNET_PACKED;
214 * Timestamp. Used to prevent reply of ancient messages
215 * (recent messages are caught with the sequence number).
217 struct GNUNET_TIME_AbsoluteNBO timestamp;
222 * We're sending an (encrypted) PING to the other peer to check if he
223 * can decrypt. The other peer should respond with a PONG with the
224 * same content, except this time encrypted with the receiver's key.
229 * Message type is either CORE_PING or CORE_PONG.
231 struct GNUNET_MessageHeader header;
234 * Random number chosen to make reply harder.
236 uint32_t challenge GNUNET_PACKED;
239 * Intended target of the PING, used primarily to check
240 * that decryption actually worked.
242 struct GNUNET_PeerIdentity target;
247 * Message transmitted to set (or update) a session key.
253 * Message type is either CORE_SET_KEY.
255 struct GNUNET_MessageHeader header;
258 * Status of the sender (should be in "enum PeerStateMachine"), nbo.
260 int32_t sender_status GNUNET_PACKED;
263 * Purpose of the signature, will be
264 * GNUNET_SIGNATURE_PURPOSE_SET_KEY.
266 struct GNUNET_CRYPTO_RsaSignaturePurpose purpose;
269 * At what time was this key created?
271 struct GNUNET_TIME_AbsoluteNBO creation_time;
274 * The encrypted session key.
276 struct GNUNET_CRYPTO_RsaEncryptedData encrypted_key;
279 * Who is the intended recipient?
281 struct GNUNET_PeerIdentity target;
284 * Signature of the stuff above (starting at purpose).
286 struct GNUNET_CRYPTO_RsaSignature signature;
292 * Message waiting for transmission. This struct
293 * is followed by the actual content of the message.
299 * We keep messages in a doubly linked list.
301 struct MessageEntry *next;
304 * We keep messages in a doubly linked list.
306 struct MessageEntry *prev;
309 * By when are we supposed to transmit this message?
311 struct GNUNET_TIME_Absolute deadline;
314 * How important is this message to us?
316 unsigned int priority;
319 * How long is the message? (number of bytes following
320 * the "struct MessageEntry", but not including the
321 * size of "struct MessageEntry" itself!)
326 * Was this message selected for transmission in the
327 * current round? GNUNET_YES or GNUNET_NO.
332 * Did we give this message some slack (delayed sending) previously
333 * (and hence should not give it any more slack)? GNUNET_YES or
344 * We keep neighbours in a linked list (for now).
346 struct Neighbour *next;
349 * Unencrypted messages destined for this peer.
351 struct MessageEntry *messages;
354 * Head of the batched, encrypted message queue (already ordered,
355 * transmit starting with the head).
357 struct MessageEntry *encrypted_head;
360 * Tail of the batched, encrypted message queue (already ordered,
361 * append new messages to tail)
363 struct MessageEntry *encrypted_tail;
366 * Handle for pending requests for transmission to this peer
367 * with the transport service. NULL if no request is pending.
369 struct GNUNET_TRANSPORT_TransmitHandle *th;
372 * Public key of the neighbour, NULL if we don't have it yet.
374 struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *public_key;
377 * We received a PING message before we got the "public_key"
378 * (or the SET_KEY). We keep it here until we have a key
379 * to decrypt it. NULL if no PING is pending.
381 struct PingMessage *pending_ping;
384 * We received a PONG message before we got the "public_key"
385 * (or the SET_KEY). We keep it here until we have a key
386 * to decrypt it. NULL if no PONG is pending.
388 struct PingMessage *pending_pong;
391 * Non-NULL if we are currently looking up HELLOs for this peer.
394 struct GNUNET_PEERINFO_IteratorContext *pitr;
397 * SetKeyMessage to transmit, NULL if we are not currently trying
400 struct SetKeyMessage *skm;
403 * Identity of the neighbour.
405 struct GNUNET_PeerIdentity peer;
408 * Key we use to encrypt our messages for the other peer
409 * (initialized by us when we do the handshake).
411 struct GNUNET_CRYPTO_AesSessionKey encrypt_key;
414 * Key we use to decrypt messages from the other peer
415 * (given to us by the other peer during the handshake).
417 struct GNUNET_CRYPTO_AesSessionKey decrypt_key;
420 * ID of task used for re-trying plaintext scheduling.
422 GNUNET_SCHEDULER_TaskIdentifier retry_plaintext_task;
425 * ID of task used for re-trying SET_KEY and PING message.
427 GNUNET_SCHEDULER_TaskIdentifier retry_set_key_task;
430 * ID of task used for updating bandwidth quota for this neighbour.
432 GNUNET_SCHEDULER_TaskIdentifier quota_update_task;
435 * ID of task used for cleaning up dead neighbour entries.
437 GNUNET_SCHEDULER_TaskIdentifier dead_clean_task;
440 * At what time did we generate our encryption key?
442 struct GNUNET_TIME_Absolute encrypt_key_created;
445 * At what time did the other peer generate the decryption key?
447 struct GNUNET_TIME_Absolute decrypt_key_created;
450 * At what time did we initially establish (as in, complete session
451 * key handshake) this connection? Should be zero if status != KEY_CONFIRMED.
453 struct GNUNET_TIME_Absolute time_established;
456 * At what time did we last receive an encrypted message from the
457 * other peer? Should be zero if status != KEY_CONFIRMED.
459 struct GNUNET_TIME_Absolute last_activity;
462 * Last latency observed from this peer.
464 struct GNUNET_TIME_Relative last_latency;
467 * At what frequency are we currently re-trying SET_KEY messages?
469 struct GNUNET_TIME_Relative set_key_retry_frequency;
472 * Time of our last update to the "available_send_window".
474 struct GNUNET_TIME_Absolute last_asw_update;
477 * Time of our last update to the "available_recv_window".
479 struct GNUNET_TIME_Absolute last_arw_update;
482 * Number of bytes that we are eligible to transmit to this
483 * peer at this point. Incremented every minute by max_out_bpm,
484 * bounded by max_bpm (no back-log larger than MAX_BUF_FACT minutes,
485 * bandwidth-hogs are sampled at a frequency of about 78s!);
486 * may get negative if we have VERY high priority content.
488 long long available_send_window;
491 * How much downstream capacity of this peer has been reserved for
492 * our traffic? (Our clients can request that a certain amount of
493 * bandwidth is available for replies to them; this value is used to
494 * make sure that this reserved amount of bandwidth is actually
497 long long available_recv_window;
500 * How valueable were the messages of this peer recently?
502 unsigned long long current_preference;
505 * Bit map indicating which of the 32 sequence numbers before the last
506 * were received (good for accepting out-of-order packets and
507 * estimating reliability of the connection)
509 unsigned int last_packets_bitmap;
512 * last sequence number received on this connection (highest)
514 uint32_t last_sequence_number_received;
517 * last sequence number transmitted
519 uint32_t last_sequence_number_sent;
522 * Available bandwidth in for this peer (current target).
527 * Available bandwidth out for this peer (current target).
532 * Internal bandwidth limit set for this peer (initially
533 * typically set to "-1"). "bpm_out" is MAX of
534 * "bpm_out_internal_limit" and "bpm_out_external_limit".
536 uint32_t bpm_out_internal_limit;
539 * External bandwidth limit set for this peer by the
540 * peer that we are communicating with. "bpm_out" is MAX of
541 * "bpm_out_internal_limit" and "bpm_out_external_limit".
543 uint32_t bpm_out_external_limit;
546 * What was our PING challenge number (for this peer)?
548 uint32_t ping_challenge;
551 * What was the last distance to this peer as reported by the transports?
553 uint32_t last_distance;
556 * What is our connection status?
558 enum PeerStateMachine status;
561 * Are we currently connected to this neighbour?
568 * Data structure for each client connected to the core service.
573 * Clients are kept in a linked list.
578 * Handle for the client with the server API.
580 struct GNUNET_SERVER_Client *client_handle;
583 * Array of the types of messages this peer cares
584 * about (with "tcnt" entries). Allocated as part
585 * of this client struct, do not free!
587 const uint16_t *types;
590 * Options for messages this client cares about,
591 * see GNUNET_CORE_OPTION_ values.
596 * Number of types of incoming messages this client
597 * specifically cares about. Size of the "types" array.
607 static struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded my_public_key;
612 static struct GNUNET_PeerIdentity my_identity;
617 static struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key;
622 struct GNUNET_SCHEDULER_Handle *sched;
627 const struct GNUNET_CONFIGURATION_Handle *cfg;
632 static struct GNUNET_SERVER_Handle *server;
637 static struct GNUNET_TRANSPORT_Handle *transport;
640 * Linked list of our clients.
642 static struct Client *clients;
645 * Context for notifications we need to send to our clients.
647 static struct GNUNET_SERVER_NotificationContext *notifier;
650 * We keep neighbours in a linked list (for now).
652 static struct Neighbour *neighbours;
655 * Sum of all preferences among all neighbours.
657 static unsigned long long preference_sum;
660 * Total number of neighbours we have.
662 static unsigned int neighbour_count;
665 * How much inbound bandwidth are we supposed to be using?
667 static unsigned long long bandwidth_target_in;
670 * How much outbound bandwidth are we supposed to be using?
672 static unsigned long long bandwidth_target_out;
677 * A preference value for a neighbour was update. Update
678 * the preference sum accordingly.
680 * @param inc how much was a preference value increased?
683 update_preference_sum (unsigned long long inc)
686 unsigned long long os;
689 preference_sum += inc;
690 if (preference_sum >= os)
692 /* overflow! compensate by cutting all values in half! */
697 n->current_preference /= 2;
698 preference_sum += n->current_preference;
705 * Recalculate the number of bytes we expect to
706 * receive or transmit in a given window.
708 * @param force force an update now (even if not much time has passed)
709 * @param window pointer to the byte counter (updated)
710 * @param ts pointer to the timestamp (updated)
711 * @param bpm number of bytes per minute that should
712 * be added to the window.
715 update_window (int force,
717 struct GNUNET_TIME_Absolute *ts, unsigned int bpm)
719 struct GNUNET_TIME_Relative since;
720 unsigned long long increment;
722 since = GNUNET_TIME_absolute_get_duration (*ts);
723 increment = (bpm * since.value) / 60 / 1000;
724 if ( (force == GNUNET_NO) &&
725 (since.value < 60 * 1000) &&
726 (increment < 32 * 1024) )
727 return; /* not even a minute has passed */
728 *ts = GNUNET_TIME_absolute_get ();
729 *window += increment;
730 if (*window > MAX_WINDOW_TIME * bpm)
731 *window = MAX_WINDOW_TIME * bpm;
736 * Find the entry for the given neighbour.
738 * @param peer identity of the neighbour
739 * @return NULL if we are not connected, otherwise the
742 static struct Neighbour *
743 find_neighbour (const struct GNUNET_PeerIdentity *peer)
745 struct Neighbour *ret;
748 while ((ret != NULL) &&
749 (0 != memcmp (&ret->peer,
750 peer, sizeof (struct GNUNET_PeerIdentity))))
757 * Send a message to one of our clients.
759 * @param client target for the message
760 * @param msg message to transmit
761 * @param can_drop could this message be dropped if the
762 * client's queue is getting too large?
765 send_to_client (struct Client *client,
766 const struct GNUNET_MessageHeader *msg,
769 #if DEBUG_CORE_CLIENT
770 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
771 "Preparing to send message of type %u to client.\n",
774 GNUNET_SERVER_notification_context_unicast (notifier,
775 client->client_handle,
782 * Send a message to all of our current clients that have
783 * the right options set.
785 * @param msg message to multicast
786 * @param can_drop can this message be discarded if the queue is too long
787 * @param options mask to use
790 send_to_all_clients (const struct GNUNET_MessageHeader *msg,
799 if (0 != (c->options & options))
800 send_to_client (c, msg, can_drop);
807 * Handle CORE_INIT request.
810 handle_client_init (void *cls,
811 struct GNUNET_SERVER_Client *client,
812 const struct GNUNET_MessageHeader *message)
814 const struct InitMessage *im;
815 struct InitReplyMessage irm;
818 const uint16_t *types;
821 struct ConnectNotifyMessage cnm;
824 #if DEBUG_CORE_CLIENT
825 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
826 "Client connecting to core service with `%s' message\n",
829 /* check that we don't have an entry already */
833 if (client == c->client_handle)
836 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
841 msize = ntohs (message->size);
842 if (msize < sizeof (struct InitMessage))
845 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
848 GNUNET_SERVER_notification_context_add (notifier, client);
849 im = (const struct InitMessage *) message;
850 types = (const uint16_t *) &im[1];
851 msize -= sizeof (struct InitMessage);
852 c = GNUNET_malloc (sizeof (struct Client) + msize);
853 c->client_handle = client;
856 c->tcnt = msize / sizeof (uint16_t);
857 c->types = (const uint16_t *) &c[1];
858 wtypes = (uint16_t *) &c[1];
859 for (i=0;i<c->tcnt;i++)
860 wtypes[i] = ntohs (types[i]);
861 c->options = ntohl (im->options);
862 #if DEBUG_CORE_CLIENT
863 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
864 "Client %p is interested in %u message types\n",
868 /* send init reply message */
869 irm.header.size = htons (sizeof (struct InitReplyMessage));
870 irm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_INIT_REPLY);
871 irm.reserved = htonl (0);
872 memcpy (&irm.publicKey,
874 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
875 #if DEBUG_CORE_CLIENT
876 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
877 "Sending `%s' message to client.\n", "INIT_REPLY");
879 send_to_client (c, &irm.header, GNUNET_NO);
880 /* notify new client about existing neighbours */
881 cnm.header.size = htons (sizeof (struct ConnectNotifyMessage));
882 cnm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_CONNECT);
886 if (n->status == PEER_STATE_KEY_CONFIRMED)
888 #if DEBUG_CORE_CLIENT
889 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
890 "Sending `%s' message to client.\n", "NOTIFY_CONNECT");
892 cnm.distance = htonl (n->last_distance);
893 cnm.latency = GNUNET_TIME_relative_hton (n->last_latency);
895 send_to_client (c, &cnm.header, GNUNET_NO);
899 GNUNET_SERVER_receive_done (client, GNUNET_OK);
904 * A client disconnected, clean up.
907 * @param client identification of the client
910 handle_client_disconnect (void *cls, struct GNUNET_SERVER_Client *client)
917 #if DEBUG_CORE_CLIENT
918 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
919 "Client %p has disconnected from core service.\n",
926 if (client == pos->client_handle)
931 prev->next = pos->next;
938 /* client never sent INIT */
943 * Handle REQUEST_INFO request.
946 handle_client_request_info (void *cls,
947 struct GNUNET_SERVER_Client *client,
948 const struct GNUNET_MessageHeader *message)
950 const struct RequestInfoMessage *rcm;
952 struct ConfigurationInfoMessage cim;
955 unsigned long long old_preference;
956 struct GNUNET_SERVER_TransmitContext *tc;
958 #if DEBUG_CORE_CLIENT
959 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
960 "Core service receives `%s' request.\n", "REQUEST_INFO");
962 rcm = (const struct RequestInfoMessage *) message;
963 n = find_neighbour (&rcm->peer);
964 memset (&cim, 0, sizeof (cim));
967 update_window (GNUNET_YES,
968 &n->available_send_window,
971 n->bpm_out_internal_limit = ntohl (rcm->limit_outbound_bpm);
972 n->bpm_out = GNUNET_MAX (n->bpm_out_internal_limit,
973 n->bpm_out_external_limit);
974 want_reserv = ntohl (rcm->reserve_inbound);
977 n->available_recv_window += want_reserv;
979 else if (want_reserv > 0)
981 update_window (GNUNET_NO,
982 &n->available_recv_window,
983 &n->last_arw_update, n->bpm_in);
984 if (n->available_recv_window < want_reserv)
985 got_reserv = 0; /* all or nothing */
987 got_reserv = want_reserv;
988 n->available_recv_window -= got_reserv;
990 old_preference = n->current_preference;
991 n->current_preference += GNUNET_ntohll(rcm->preference_change);
992 if (old_preference > n->current_preference)
994 /* overflow; cap at maximum value */
995 n->current_preference = (unsigned long long) -1;
997 update_preference_sum (n->current_preference - old_preference);
998 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
999 "Received reservation request for %d bytes for peer `%4s', reserved %d bytes\n",
1001 GNUNET_i2s (&rcm->peer),
1003 cim.reserved_amount = htonl (got_reserv);
1004 cim.bpm_in = htonl (n->bpm_in);
1005 cim.bpm_out = htonl (n->bpm_out);
1006 cim.preference = n->current_preference;
1008 cim.header.size = htons (sizeof (struct ConfigurationInfoMessage));
1009 cim.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_CONFIGURATION_INFO);
1010 cim.peer = rcm->peer;
1012 #if DEBUG_CORE_CLIENT
1013 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1014 "Sending `%s' message to client.\n", "CONFIGURATION_INFO");
1016 tc = GNUNET_SERVER_transmit_context_create (client);
1017 GNUNET_SERVER_transmit_context_append_message (tc, &cim.header);
1018 GNUNET_SERVER_transmit_context_run (tc,
1019 GNUNET_TIME_UNIT_FOREVER_REL);
1024 * Free the given entry for the neighbour (it has
1025 * already been removed from the list at this point).
1027 * @param n neighbour to free
1030 free_neighbour (struct Neighbour *n)
1032 struct MessageEntry *m;
1034 if (n->pitr != NULL)
1036 GNUNET_PEERINFO_iterate_cancel (n->pitr);
1041 GNUNET_free (n->skm);
1044 while (NULL != (m = n->messages))
1046 n->messages = m->next;
1049 while (NULL != (m = n->encrypted_head))
1051 GNUNET_CONTAINER_DLL_remove (n->encrypted_head,
1058 GNUNET_TRANSPORT_notify_transmit_ready_cancel (n->th);
1061 if (n->retry_plaintext_task != GNUNET_SCHEDULER_NO_TASK)
1062 GNUNET_SCHEDULER_cancel (sched, n->retry_plaintext_task);
1063 if (n->retry_set_key_task != GNUNET_SCHEDULER_NO_TASK)
1064 GNUNET_SCHEDULER_cancel (sched, n->retry_set_key_task);
1065 if (n->quota_update_task != GNUNET_SCHEDULER_NO_TASK)
1066 GNUNET_SCHEDULER_cancel (sched, n->quota_update_task);
1067 if (n->dead_clean_task != GNUNET_SCHEDULER_NO_TASK)
1068 GNUNET_SCHEDULER_cancel (sched, n->dead_clean_task);
1069 GNUNET_free_non_null (n->public_key);
1070 GNUNET_free_non_null (n->pending_ping);
1071 GNUNET_free_non_null (n->pending_pong);
1077 * Consider freeing the given neighbour since we may not need
1078 * to keep it around anymore.
1080 * @param n neighbour to consider discarding
1083 consider_free_neighbour (struct Neighbour *n);
1087 * Task triggered when a neighbour entry might have gotten stale.
1089 * @param cls the 'struct Neighbour'
1090 * @param tc scheduler context (not used)
1093 consider_free_task (void *cls,
1094 const struct GNUNET_SCHEDULER_TaskContext *tc)
1096 struct Neighbour *n = cls;
1097 n->dead_clean_task = GNUNET_SCHEDULER_NO_TASK;
1098 consider_free_neighbour (n);
1103 * Consider freeing the given neighbour since we may not need
1104 * to keep it around anymore.
1106 * @param n neighbour to consider discarding
1109 consider_free_neighbour (struct Neighbour *n)
1111 struct Neighbour *pos;
1112 struct Neighbour *prev;
1113 struct GNUNET_TIME_Relative left;
1115 if ( (n->th != NULL) ||
1116 (n->pitr != NULL) ||
1117 (n->status == PEER_STATE_KEY_CONFIRMED) ||
1118 (GNUNET_YES == n->is_connected) )
1119 return; /* no chance */
1121 left = GNUNET_TIME_absolute_get_remaining (GNUNET_TIME_absolute_add (n->last_activity,
1125 if (n->dead_clean_task != GNUNET_SCHEDULER_NO_TASK)
1126 GNUNET_SCHEDULER_cancel (sched, n->dead_clean_task);
1127 n->dead_clean_task = GNUNET_SCHEDULER_add_delayed (sched,
1129 &consider_free_task,
1133 /* actually free the neighbour... */
1142 neighbours = n->next;
1144 prev->next = n->next;
1145 GNUNET_assert (neighbour_count > 0);
1152 * Check if we have encrypted messages for the specified neighbour
1153 * pending, and if so, check with the transport about sending them
1156 * @param n neighbour to check.
1158 static void process_encrypted_neighbour_queue (struct Neighbour *n);
1162 * Function called when the transport service is ready to
1163 * receive an encrypted message for the respective peer
1165 * @param cls neighbour to use message from
1166 * @param size number of bytes we can transmit
1167 * @param buf where to copy the message
1168 * @return number of bytes transmitted
1171 notify_encrypted_transmit_ready (void *cls, size_t size, void *buf)
1173 struct Neighbour *n = cls;
1174 struct MessageEntry *m;
1179 GNUNET_assert (NULL != (m = n->encrypted_head));
1180 GNUNET_CONTAINER_DLL_remove (n->encrypted_head,
1187 GNUNET_assert (size >= m->size);
1188 memcpy (cbuf, &m[1], m->size);
1190 n->available_send_window -= m->size;
1191 process_encrypted_neighbour_queue (n);
1194 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1195 "Copied message of type %u and size %u into transport buffer for `%4s'\n",
1196 ntohs (((struct GNUNET_MessageHeader *) &m[1])->type),
1197 ret, GNUNET_i2s (&n->peer));
1203 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1204 "Transmission of message of type %u and size %u failed\n",
1205 ntohs (((struct GNUNET_MessageHeader *) &m[1])->type),
1210 consider_free_neighbour (n);
1216 * Check if we have plaintext messages for the specified neighbour
1217 * pending, and if so, consider batching and encrypting them (and
1218 * then trigger processing of the encrypted queue if needed).
1220 * @param n neighbour to check.
1222 static void process_plaintext_neighbour_queue (struct Neighbour *n);
1226 * Check if we have encrypted messages for the specified neighbour
1227 * pending, and if so, check with the transport about sending them
1230 * @param n neighbour to check.
1233 process_encrypted_neighbour_queue (struct Neighbour *n)
1235 struct MessageEntry *m;
1238 return; /* request already pending */
1239 m = n->encrypted_head;
1242 /* encrypted queue empty, try plaintext instead */
1243 process_plaintext_neighbour_queue (n);
1247 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1248 "Asking transport for transmission of %u bytes to `%4s' in next %llu ms\n",
1250 GNUNET_i2s (&n->peer),
1251 GNUNET_TIME_absolute_get_remaining (m->deadline).
1255 GNUNET_TRANSPORT_notify_transmit_ready (transport, &n->peer,
1258 GNUNET_TIME_absolute_get_remaining
1260 ¬ify_encrypted_transmit_ready,
1264 /* message request too large or duplicate request */
1266 /* discard encrypted message */
1267 GNUNET_CONTAINER_DLL_remove (n->encrypted_head,
1271 process_encrypted_neighbour_queue (n);
1277 * Decrypt size bytes from in and write the result to out. Use the
1278 * key for inbound traffic of the given neighbour. This function does
1279 * NOT do any integrity-checks on the result.
1281 * @param n neighbour we are receiving from
1282 * @param iv initialization vector to use
1283 * @param in ciphertext
1284 * @param out plaintext
1285 * @param size size of in/out
1286 * @return GNUNET_OK on success
1289 do_decrypt (struct Neighbour *n,
1290 const GNUNET_HashCode * iv,
1291 const void *in, void *out, size_t size)
1293 if (size != (uint16_t) size)
1298 if ((n->status != PEER_STATE_KEY_RECEIVED) &&
1299 (n->status != PEER_STATE_KEY_CONFIRMED))
1301 GNUNET_break_op (0);
1302 return GNUNET_SYSERR;
1305 GNUNET_CRYPTO_aes_decrypt (in,
1309 GNUNET_CRYPTO_AesInitializationVector *) iv,
1313 return GNUNET_SYSERR;
1316 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1317 "Decrypted %u bytes from `%4s' using key %u\n",
1318 size, GNUNET_i2s (&n->peer), n->decrypt_key.crc32);
1325 * Encrypt size bytes from in and write the result to out. Use the
1326 * key for outbound traffic of the given neighbour.
1328 * @param n neighbour we are sending to
1329 * @param iv initialization vector to use
1330 * @param in ciphertext
1331 * @param out plaintext
1332 * @param size size of in/out
1333 * @return GNUNET_OK on success
1336 do_encrypt (struct Neighbour *n,
1337 const GNUNET_HashCode * iv,
1338 const void *in, void *out, size_t size)
1340 if (size != (uint16_t) size)
1345 GNUNET_assert (size ==
1346 GNUNET_CRYPTO_aes_encrypt (in,
1350 GNUNET_CRYPTO_AesInitializationVector
1353 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1354 "Encrypted %u bytes for `%4s' using key %u\n", size,
1355 GNUNET_i2s (&n->peer), n->encrypt_key.crc32);
1362 * Select messages for transmission. This heuristic uses a combination
1363 * of earliest deadline first (EDF) scheduling (with bounded horizon)
1364 * and priority-based discard (in case no feasible schedule exist) and
1365 * speculative optimization (defer any kind of transmission until
1366 * we either create a batch of significant size, 25% of max, or until
1367 * we are close to a deadline). Furthermore, when scheduling the
1368 * heuristic also packs as many messages into the batch as possible,
1369 * starting with those with the earliest deadline. Yes, this is fun.
1371 * @param n neighbour to select messages from
1372 * @param size number of bytes to select for transmission
1373 * @param retry_time set to the time when we should try again
1374 * (only valid if this function returns zero)
1375 * @return number of bytes selected, or 0 if we decided to
1376 * defer scheduling overall; in that case, retry_time is set.
1379 select_messages (struct Neighbour *n,
1380 size_t size, struct GNUNET_TIME_Relative *retry_time)
1382 struct MessageEntry *pos;
1383 struct MessageEntry *min;
1384 struct MessageEntry *last;
1385 unsigned int min_prio;
1386 struct GNUNET_TIME_Absolute t;
1387 struct GNUNET_TIME_Absolute now;
1390 unsigned long long slack; /* how long could we wait before missing deadlines? */
1392 int discard_low_prio;
1394 GNUNET_assert (NULL != n->messages);
1395 now = GNUNET_TIME_absolute_get ();
1396 /* last entry in linked list of messages processed */
1398 /* should we remove the entry with the lowest
1399 priority from consideration for scheduling at the
1401 discard_low_prio = GNUNET_YES;
1402 while (GNUNET_YES == discard_low_prio)
1406 discard_low_prio = GNUNET_NO;
1407 /* calculate number of bytes available for transmission at time "t" */
1408 update_window (GNUNET_NO,
1409 &n->available_send_window,
1410 &n->last_asw_update,
1412 avail = n->available_send_window;
1413 t = n->last_asw_update;
1414 /* how many bytes have we (hypothetically) scheduled so far */
1416 /* maximum time we can wait before transmitting anything
1417 and still make all of our deadlines */
1421 /* note that we use "*2" here because we want to look
1422 a bit further into the future; much more makes no
1423 sense since new message might be scheduled in the
1425 while ((pos != NULL) && (off < size * 2))
1427 if (pos->do_transmit == GNUNET_YES)
1429 /* already removed from consideration */
1433 if (discard_low_prio == GNUNET_NO)
1435 delta = pos->deadline.value;
1436 if (delta < t.value)
1439 delta = t.value - delta;
1440 avail += delta * n->bpm_out / 1000 / 60;
1441 if (avail < pos->size)
1443 discard_low_prio = GNUNET_YES; /* we could not schedule this one! */
1448 /* update slack, considering both its absolute deadline
1449 and relative deadlines caused by other messages
1450 with their respective load */
1451 slack = GNUNET_MIN (slack, avail / n->bpm_out);
1452 if ( (pos->deadline.value < now.value) ||
1453 (GNUNET_YES == pos->got_slack) )
1460 GNUNET_MIN (slack, pos->deadline.value - now.value);
1461 pos->got_slack = GNUNET_YES;
1467 t.value = GNUNET_MAX (pos->deadline.value, t.value);
1468 if (pos->priority <= min_prio)
1470 /* update min for discard */
1471 min_prio = pos->priority;
1476 if (discard_low_prio)
1478 GNUNET_assert (min != NULL);
1479 /* remove lowest-priority entry from consideration */
1480 min->do_transmit = GNUNET_YES; /* means: discard (for now) */
1484 /* guard against sending "tiny" messages with large headers without
1486 if ( (slack > 1000) && (size > 4 * off) )
1488 /* less than 25% of message would be filled with deadlines still
1489 being met if we delay by one second or more; so just wait for
1490 more data; but do not wait longer than 1s (since we don't want
1491 to delay messages for a really long time either). */
1492 retry_time->value = 1000;
1493 /* reset do_transmit values for next time */
1496 pos->do_transmit = GNUNET_NO;
1500 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1501 "Deferring transmission for 1s due to underfull message buffer size\n");
1505 /* select marked messages (up to size) for transmission */
1510 if ((pos->size <= size) && (pos->do_transmit == GNUNET_NO))
1512 pos->do_transmit = GNUNET_YES; /* mark for transmission */
1517 pos->do_transmit = GNUNET_NO; /* mark for not transmitting! */
1521 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1522 "Selected %u bytes of plaintext messages for transmission to `%4s'.\n",
1523 off, GNUNET_i2s (&n->peer));
1530 * Batch multiple messages into a larger buffer.
1532 * @param n neighbour to take messages from
1533 * @param buf target buffer
1534 * @param size size of buf
1535 * @param deadline set to transmission deadline for the result
1536 * @param retry_time set to the time when we should try again
1537 * (only valid if this function returns zero)
1538 * @param priority set to the priority of the batch
1539 * @return number of bytes written to buf (can be zero)
1542 batch_message (struct Neighbour *n,
1545 struct GNUNET_TIME_Absolute *deadline,
1546 struct GNUNET_TIME_Relative *retry_time,
1547 unsigned int *priority)
1549 char ntmb[GNUNET_SERVER_MAX_MESSAGE_SIZE];
1550 struct NotifyTrafficMessage *ntm = (struct NotifyTrafficMessage*) ntmb;
1551 struct MessageEntry *pos;
1552 struct MessageEntry *prev;
1553 struct MessageEntry *next;
1558 *deadline = GNUNET_TIME_UNIT_FOREVER_ABS;
1559 *retry_time = GNUNET_TIME_UNIT_FOREVER_REL;
1560 if (0 == select_messages (n, size, retry_time))
1562 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1563 "No messages selected, will try again in %llu ms\n",
1567 ntm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_OUTBOUND);
1568 ntm->distance = htonl (n->last_distance);
1569 ntm->latency = GNUNET_TIME_relative_hton (n->last_latency);
1570 ntm->peer = n->peer;
1574 while ((pos != NULL) && (size >= sizeof (struct GNUNET_MessageHeader)))
1577 if (GNUNET_YES == pos->do_transmit)
1579 GNUNET_assert (pos->size <= size);
1580 /* do notifications */
1581 /* FIXME: track if we have *any* client that wants
1582 full notifications and only do this if that is
1584 if (pos->size < GNUNET_SERVER_MAX_MESSAGE_SIZE - sizeof (struct NotifyTrafficMessage))
1586 memcpy (&ntm[1], &pos[1], pos->size);
1587 ntm->header.size = htons (sizeof (struct NotifyTrafficMessage) +
1588 sizeof (struct GNUNET_MessageHeader));
1589 send_to_all_clients (&ntm->header,
1591 GNUNET_CORE_OPTION_SEND_HDR_OUTBOUND);
1595 /* message too large for 'full' notifications, we do at
1596 least the 'hdr' type */
1599 sizeof (struct GNUNET_MessageHeader));
1601 ntm->header.size = htons (sizeof (struct NotifyTrafficMessage) +
1603 send_to_all_clients (&ntm->header,
1605 GNUNET_CORE_OPTION_SEND_FULL_OUTBOUND);
1608 "Encrypting message of type %u\n",
1609 ntohs(((struct GNUNET_MessageHeader*)&pos[1])->type));
1611 /* copy for encrypted transmission */
1612 memcpy (&buf[ret], &pos[1], pos->size);
1615 *priority += pos->priority;
1617 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1618 "Adding plaintext message with deadline %llu ms to batch\n",
1619 GNUNET_TIME_absolute_get_remaining (pos->deadline).value);
1621 deadline->value = GNUNET_MIN (deadline->value, pos->deadline.value);
1635 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1636 "Deadline for message batch is %llu ms\n",
1637 GNUNET_TIME_absolute_get_remaining (*deadline).value);
1644 * Remove messages with deadlines that have long expired from
1647 * @param n neighbour to inspect
1650 discard_expired_messages (struct Neighbour *n)
1652 struct MessageEntry *prev;
1653 struct MessageEntry *next;
1654 struct MessageEntry *pos;
1655 struct GNUNET_TIME_Absolute now;
1656 struct GNUNET_TIME_Relative delta;
1658 now = GNUNET_TIME_absolute_get ();
1664 delta = GNUNET_TIME_absolute_get_difference (pos->deadline, now);
1665 if (delta.value > PAST_EXPIRATION_DISCARD_TIME.value)
1668 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1669 "Message is %llu ms past due, discarding.\n",
1686 * Signature of the main function of a task.
1688 * @param cls closure
1689 * @param tc context information (why was this task triggered now)
1692 retry_plaintext_processing (void *cls,
1693 const struct GNUNET_SCHEDULER_TaskContext *tc)
1695 struct Neighbour *n = cls;
1697 n->retry_plaintext_task = GNUNET_SCHEDULER_NO_TASK;
1698 process_plaintext_neighbour_queue (n);
1703 * Send our key (and encrypted PING) to the other peer.
1705 * @param n the other peer
1707 static void send_key (struct Neighbour *n);
1710 * Task that will retry "send_key" if our previous attempt failed
1714 set_key_retry_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1716 struct Neighbour *n = cls;
1718 n->retry_set_key_task = GNUNET_SCHEDULER_NO_TASK;
1719 n->set_key_retry_frequency =
1720 GNUNET_TIME_relative_multiply (n->set_key_retry_frequency, 2);
1726 * Check if we have plaintext messages for the specified neighbour
1727 * pending, and if so, consider batching and encrypting them (and
1728 * then trigger processing of the encrypted queue if needed).
1730 * @param n neighbour to check.
1733 process_plaintext_neighbour_queue (struct Neighbour *n)
1735 char pbuf[MAX_ENCRYPTED_MESSAGE_SIZE]; /* plaintext */
1738 struct EncryptedMessage *em; /* encrypted message */
1739 struct EncryptedMessage *ph; /* plaintext header */
1740 struct MessageEntry *me;
1741 unsigned int priority;
1742 struct GNUNET_TIME_Absolute deadline;
1743 struct GNUNET_TIME_Relative retry_time;
1746 if (n->retry_plaintext_task != GNUNET_SCHEDULER_NO_TASK)
1748 GNUNET_SCHEDULER_cancel (sched, n->retry_plaintext_task);
1749 n->retry_plaintext_task = GNUNET_SCHEDULER_NO_TASK;
1753 case PEER_STATE_DOWN:
1756 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1757 "Not yet connected to `%4s', deferring processing of plaintext messages.\n",
1758 GNUNET_i2s(&n->peer));
1761 case PEER_STATE_KEY_SENT:
1762 if (n->retry_set_key_task == GNUNET_SCHEDULER_NO_TASK)
1763 n->retry_set_key_task
1764 = GNUNET_SCHEDULER_add_delayed (sched,
1765 n->set_key_retry_frequency,
1766 &set_key_retry_task, n);
1768 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1769 "Not yet connected to `%4s', deferring processing of plaintext messages.\n",
1770 GNUNET_i2s(&n->peer));
1773 case PEER_STATE_KEY_RECEIVED:
1774 if (n->retry_set_key_task == GNUNET_SCHEDULER_NO_TASK)
1775 n->retry_set_key_task
1776 = GNUNET_SCHEDULER_add_delayed (sched,
1777 n->set_key_retry_frequency,
1778 &set_key_retry_task, n);
1780 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1781 "Not yet connected to `%4s', deferring processing of plaintext messages.\n",
1782 GNUNET_i2s(&n->peer));
1785 case PEER_STATE_KEY_CONFIRMED:
1786 /* ready to continue */
1789 discard_expired_messages (n);
1790 if (n->messages == NULL)
1793 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1794 "Plaintext message queue for `%4s' is empty.\n",
1795 GNUNET_i2s(&n->peer));
1797 return; /* no pending messages */
1799 if (n->encrypted_head != NULL)
1802 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1803 "Encrypted message queue for `%4s' is still full, delaying plaintext processing.\n",
1804 GNUNET_i2s(&n->peer));
1806 return; /* wait for messages already encrypted to be
1809 ph = (struct EncryptedMessage *) pbuf;
1810 deadline = GNUNET_TIME_UNIT_FOREVER_ABS;
1812 used = sizeof (struct EncryptedMessage);
1813 used += batch_message (n,
1815 MAX_ENCRYPTED_MESSAGE_SIZE - used,
1816 &deadline, &retry_time, &priority);
1817 if (used == sizeof (struct EncryptedMessage))
1820 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1821 "No messages selected for transmission to `%4s' at this time, will try again later.\n",
1822 GNUNET_i2s(&n->peer));
1824 /* no messages selected for sending, try again later... */
1825 n->retry_plaintext_task =
1826 GNUNET_SCHEDULER_add_delayed (sched,
1828 &retry_plaintext_processing, n);
1831 ph->iv_seed = htonl (GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, -1));
1832 ph->sequence_number = htonl (++n->last_sequence_number_sent);
1833 ph->inbound_bpm_limit = htonl (n->bpm_in);
1834 ph->timestamp = GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
1836 /* setup encryption message header */
1837 me = GNUNET_malloc (sizeof (struct MessageEntry) + used);
1838 me->deadline = deadline;
1839 me->priority = priority;
1841 em = (struct EncryptedMessage *) &me[1];
1842 em->header.size = htons (used);
1843 em->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_ENCRYPTED_MESSAGE);
1844 em->iv_seed = ph->iv_seed;
1845 esize = used - ENCRYPTED_HEADER_SIZE;
1846 GNUNET_CRYPTO_hash (&ph->sequence_number,
1847 esize - sizeof (GNUNET_HashCode),
1848 &ph->plaintext_hash);
1849 GNUNET_CRYPTO_hash (&ph->iv_seed, sizeof (uint32_t), &iv);
1852 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1853 "Encrypting %u bytes of plaintext messages for `%4s' for transmission in %llums.\n",
1855 GNUNET_i2s(&n->peer),
1856 (unsigned long long) GNUNET_TIME_absolute_get_remaining (deadline).value);
1858 GNUNET_assert (GNUNET_OK ==
1861 &ph->plaintext_hash,
1862 &em->plaintext_hash, esize));
1863 /* append to transmission list */
1864 GNUNET_CONTAINER_DLL_insert_after (n->encrypted_head,
1868 process_encrypted_neighbour_queue (n);
1873 * Function that recalculates the bandwidth quota for the
1874 * given neighbour and transmits it to the transport service.
1876 * @param cls neighbour for the quota update
1880 neighbour_quota_update (void *cls,
1881 const struct GNUNET_SCHEDULER_TaskContext *tc);
1885 * Schedule the task that will recalculate the bandwidth
1886 * quota for this peer (and possibly force a disconnect of
1887 * idle peers by calculating a bandwidth of zero).
1890 schedule_quota_update (struct Neighbour *n)
1892 GNUNET_assert (n->quota_update_task ==
1893 GNUNET_SCHEDULER_NO_TASK);
1894 n->quota_update_task
1895 = GNUNET_SCHEDULER_add_delayed (sched,
1896 QUOTA_UPDATE_FREQUENCY,
1897 &neighbour_quota_update,
1903 * Initialize a new 'struct Neighbour'.
1905 * @param pid ID of the new neighbour
1906 * @return handle for the new neighbour
1908 static struct Neighbour *
1909 create_neighbour (const struct GNUNET_PeerIdentity *pid)
1911 struct Neighbour *n;
1912 struct GNUNET_TIME_Absolute now;
1914 n = GNUNET_malloc (sizeof (struct Neighbour));
1915 n->next = neighbours;
1919 GNUNET_CRYPTO_aes_create_session_key (&n->encrypt_key);
1920 now = GNUNET_TIME_absolute_get ();
1921 n->encrypt_key_created = now;
1922 n->last_activity = now;
1923 n->set_key_retry_frequency = INITIAL_SET_KEY_RETRY_FREQUENCY;
1924 n->bpm_in = GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT;
1925 n->bpm_out = GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT;
1926 n->bpm_out_internal_limit = (uint32_t) - 1;
1927 n->bpm_out_external_limit = GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT;
1928 n->ping_challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1930 schedule_quota_update (n);
1939 * Handle CORE_SEND request.
1942 * @param client the client issuing the request
1943 * @param message the "struct SendMessage"
1946 handle_client_send (void *cls,
1947 struct GNUNET_SERVER_Client *client,
1948 const struct GNUNET_MessageHeader *message)
1950 const struct SendMessage *sm;
1951 const struct GNUNET_MessageHeader *mh;
1952 struct Neighbour *n;
1953 struct MessageEntry *prev;
1954 struct MessageEntry *pos;
1955 struct MessageEntry *e;
1956 struct MessageEntry *min_prio_entry;
1957 struct MessageEntry *min_prio_prev;
1958 unsigned int min_prio;
1959 unsigned int queue_size;
1962 msize = ntohs (message->size);
1964 sizeof (struct SendMessage) + sizeof (struct GNUNET_MessageHeader))
1968 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1971 sm = (const struct SendMessage *) message;
1972 msize -= sizeof (struct SendMessage);
1973 mh = (const struct GNUNET_MessageHeader *) &sm[1];
1974 if (msize != ntohs (mh->size))
1978 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1981 n = find_neighbour (&sm->peer);
1983 n = create_neighbour (&sm->peer);
1985 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1986 "Core received `%s' request, queueing %u bytes of plaintext data for transmission to `%4s'.\n",
1989 GNUNET_i2s (&sm->peer));
1991 /* bound queue size */
1992 discard_expired_messages (n);
1993 min_prio = (unsigned int) -1;
1994 min_prio_entry = NULL;
1995 min_prio_prev = NULL;
2001 if (pos->priority < min_prio)
2003 min_prio_entry = pos;
2004 min_prio_prev = prev;
2005 min_prio = pos->priority;
2011 if (queue_size >= MAX_PEER_QUEUE_SIZE)
2014 if (ntohl(sm->priority) <= min_prio)
2016 /* discard new entry */
2018 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2019 "Queue full, discarding new request\n");
2022 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2025 /* discard "min_prio_entry" */
2027 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2028 "Queue full, discarding existing older request\n");
2030 if (min_prio_prev == NULL)
2031 n->messages = min_prio_entry->next;
2033 min_prio_prev->next = min_prio_entry->next;
2034 GNUNET_free (min_prio_entry);
2038 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2039 "Adding transmission request for `%4s' to queue\n",
2040 GNUNET_i2s (&sm->peer));
2042 e = GNUNET_malloc (sizeof (struct MessageEntry) + msize);
2043 e->deadline = GNUNET_TIME_absolute_ntoh (sm->deadline);
2044 e->priority = ntohl (sm->priority);
2046 memcpy (&e[1], mh, msize);
2048 /* insert, keep list sorted by deadline */
2051 while ((pos != NULL) && (pos->deadline.value < e->deadline.value))
2062 /* consider scheduling now */
2063 process_plaintext_neighbour_queue (n);
2065 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2070 * Function called when the transport service is ready to
2071 * receive a message. Only resets 'n->th' to NULL.
2073 * @param cls neighbour to use message from
2074 * @param size number of bytes we can transmit
2075 * @param buf where to copy the message
2076 * @return number of bytes transmitted
2079 notify_transport_connect_done (void *cls, size_t size, void *buf)
2081 struct Neighbour *n = cls;
2089 * Handle CORE_REQUEST_CONNECT request.
2092 * @param client the client issuing the request
2093 * @param message the "struct ConnectMessage"
2096 handle_client_request_connect (void *cls,
2097 struct GNUNET_SERVER_Client *client,
2098 const struct GNUNET_MessageHeader *message)
2100 const struct ConnectMessage *cm = (const struct ConnectMessage*) message;
2101 struct Neighbour *n;
2102 struct GNUNET_TIME_Relative timeout;
2104 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2105 n = find_neighbour (&cm->peer);
2107 n = create_neighbour (&cm->peer);
2108 if ( (n->is_connected) ||
2110 return; /* already connected, or at least trying */
2112 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2113 "Core received `%s' request for `%4s', will try to establish connection\n",
2115 GNUNET_i2s (&cm->peer));
2117 timeout = GNUNET_TIME_relative_ntoh (cm->timeout);
2118 /* ask transport to connect to the peer */
2119 n->th = GNUNET_TRANSPORT_notify_transmit_ready (transport,
2121 sizeof (struct GNUNET_MessageHeader), 0,
2123 ¬ify_transport_connect_done,
2125 GNUNET_break (NULL != n->th);
2130 * List of handlers for the messages understood by this
2133 static struct GNUNET_SERVER_MessageHandler handlers[] = {
2134 {&handle_client_init, NULL,
2135 GNUNET_MESSAGE_TYPE_CORE_INIT, 0},
2136 {&handle_client_request_info, NULL,
2137 GNUNET_MESSAGE_TYPE_CORE_REQUEST_INFO,
2138 sizeof (struct RequestInfoMessage)},
2139 {&handle_client_send, NULL,
2140 GNUNET_MESSAGE_TYPE_CORE_SEND, 0},
2141 {&handle_client_request_connect, NULL,
2142 GNUNET_MESSAGE_TYPE_CORE_REQUEST_CONNECT,
2143 sizeof (struct ConnectMessage)},
2149 * PEERINFO is giving us a HELLO for a peer. Add the public key to
2150 * the neighbour's struct and retry send_key. Or, if we did not get a
2151 * HELLO, just do nothing.
2153 * @param cls the 'struct Neighbour' to retry sending the key for
2154 * @param peer the peer for which this is the HELLO
2155 * @param hello HELLO message of that peer
2156 * @param trust amount of trust we currently have in that peer
2159 process_hello_retry_send_key (void *cls,
2160 const struct GNUNET_PeerIdentity *peer,
2161 const struct GNUNET_HELLO_Message *hello,
2164 struct Neighbour *n = cls;
2169 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2170 "Entered `process_hello_retry_send_key' and `peer' is NULL!\n");
2173 if (n->public_key != NULL)
2179 if (GNUNET_SCHEDULER_NO_TASK == n->retry_set_key_task)
2180 n->retry_set_key_task
2181 = GNUNET_SCHEDULER_add_delayed (sched,
2182 n->set_key_retry_frequency,
2183 &set_key_retry_task, n);
2189 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2190 "Entered `process_hello_retry_send_key' for peer `%4s'\n",
2193 if (n->public_key != NULL)
2196 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2197 "already have public key for peer %s!! (so why are we here?)\n",
2204 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2205 "Received new `%s' message for `%4s', initiating key exchange.\n",
2210 GNUNET_malloc (sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
2211 if (GNUNET_OK != GNUNET_HELLO_get_key (hello, n->public_key))
2213 GNUNET_free (n->public_key);
2214 n->public_key = NULL;
2216 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2217 "GNUNET_HELLO_get_key returned awfully\n");
2225 * Send our key (and encrypted PING) to the other peer.
2227 * @param n the other peer
2230 send_key (struct Neighbour *n)
2232 struct SetKeyMessage *sm;
2233 struct MessageEntry *me;
2234 struct PingMessage pp;
2235 struct PingMessage *pm;
2237 if ( (n->retry_set_key_task != GNUNET_SCHEDULER_NO_TASK) ||
2241 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2242 "Key exchange in progress with `%4s'.\n",
2243 GNUNET_i2s (&n->peer));
2245 return; /* already in progress */
2249 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2250 "Asked to perform key exchange with `%4s'.\n",
2251 GNUNET_i2s (&n->peer));
2253 if (n->public_key == NULL)
2255 /* lookup n's public key, then try again */
2257 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2258 "Lacking public key for `%4s', trying to obtain one (send_key).\n",
2259 GNUNET_i2s (&n->peer));
2261 GNUNET_assert (n->pitr == NULL);
2262 n->pitr = GNUNET_PEERINFO_iterate (cfg,
2266 GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 20),
2267 &process_hello_retry_send_key, n);
2270 /* first, set key message */
2271 me = GNUNET_malloc (sizeof (struct MessageEntry) +
2272 sizeof (struct SetKeyMessage));
2273 me->deadline = GNUNET_TIME_relative_to_absolute (MAX_SET_KEY_DELAY);
2274 me->priority = SET_KEY_PRIORITY;
2275 me->size = sizeof (struct SetKeyMessage);
2276 GNUNET_CONTAINER_DLL_insert_after (n->encrypted_head,
2280 sm = (struct SetKeyMessage *) &me[1];
2281 sm->header.size = htons (sizeof (struct SetKeyMessage));
2282 sm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_SET_KEY);
2283 sm->sender_status = htonl ((int32_t) ((n->status == PEER_STATE_DOWN) ?
2284 PEER_STATE_KEY_SENT : n->status));
2286 htonl (sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
2287 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
2288 sizeof (struct GNUNET_CRYPTO_RsaEncryptedData) +
2289 sizeof (struct GNUNET_PeerIdentity));
2290 sm->purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_SET_KEY);
2291 sm->creation_time = GNUNET_TIME_absolute_hton (n->encrypt_key_created);
2292 sm->target = n->peer;
2293 GNUNET_assert (GNUNET_OK ==
2294 GNUNET_CRYPTO_rsa_encrypt (&n->encrypt_key,
2296 GNUNET_CRYPTO_AesSessionKey),
2298 &sm->encrypted_key));
2299 GNUNET_assert (GNUNET_OK ==
2300 GNUNET_CRYPTO_rsa_sign (my_private_key, &sm->purpose,
2303 /* second, encrypted PING message */
2304 me = GNUNET_malloc (sizeof (struct MessageEntry) +
2305 sizeof (struct PingMessage));
2306 me->deadline = GNUNET_TIME_relative_to_absolute (MAX_PING_DELAY);
2307 me->priority = PING_PRIORITY;
2308 me->size = sizeof (struct PingMessage);
2309 n->encrypted_tail->next = me;
2310 n->encrypted_tail = me;
2311 pm = (struct PingMessage *) &me[1];
2312 pm->header.size = htons (sizeof (struct PingMessage));
2313 pm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_PING);
2314 pp.challenge = htonl (n->ping_challenge);
2315 pp.target = n->peer;
2317 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2318 "Encrypting `%s' and `%s' messages for `%4s'.\n",
2319 "SET_KEY", "PING", GNUNET_i2s (&n->peer));
2320 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2321 "Sending `%s' to `%4s' with challenge %u encrypted using key %u\n",
2323 GNUNET_i2s (&n->peer), n->ping_challenge, n->encrypt_key.crc32);
2326 &n->peer.hashPubKey,
2329 sizeof (struct PingMessage) -
2330 sizeof (struct GNUNET_MessageHeader));
2334 case PEER_STATE_DOWN:
2335 n->status = PEER_STATE_KEY_SENT;
2337 case PEER_STATE_KEY_SENT:
2339 case PEER_STATE_KEY_RECEIVED:
2341 case PEER_STATE_KEY_CONFIRMED:
2348 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2349 "Have %llu ms left for `%s' transmission.\n",
2350 (unsigned long long) GNUNET_TIME_absolute_get_remaining (me->deadline).value,
2353 /* trigger queue processing */
2354 process_encrypted_neighbour_queue (n);
2355 if ( (n->status != PEER_STATE_KEY_CONFIRMED) &&
2356 (GNUNET_SCHEDULER_NO_TASK == n->retry_set_key_task) )
2357 n->retry_set_key_task
2358 = GNUNET_SCHEDULER_add_delayed (sched,
2359 n->set_key_retry_frequency,
2360 &set_key_retry_task, n);
2365 * We received a SET_KEY message. Validate and update
2366 * our key material and status.
2368 * @param n the neighbour from which we received message m
2369 * @param m the set key message we received
2372 handle_set_key (struct Neighbour *n, const struct SetKeyMessage *m);
2376 * PEERINFO is giving us a HELLO for a peer. Add the public key to
2377 * the neighbour's struct and retry handling the set_key message. Or,
2378 * if we did not get a HELLO, just free the set key message.
2380 * @param cls pointer to the set key message
2381 * @param peer the peer for which this is the HELLO
2382 * @param hello HELLO message of that peer
2383 * @param trust amount of trust we currently have in that peer
2386 process_hello_retry_handle_set_key (void *cls,
2387 const struct GNUNET_PeerIdentity *peer,
2388 const struct GNUNET_HELLO_Message *hello,
2391 struct Neighbour *n = cls;
2392 struct SetKeyMessage *sm = n->skm;
2401 if (n->public_key != NULL)
2402 return; /* multiple HELLOs match!? */
2404 GNUNET_malloc (sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
2405 if (GNUNET_OK != GNUNET_HELLO_get_key (hello, n->public_key))
2407 GNUNET_break_op (0);
2408 GNUNET_free (n->public_key);
2409 n->public_key = NULL;
2413 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2414 "Received `%s' for `%4s', continuing processing of `%s' message.\n",
2415 "HELLO", GNUNET_i2s (peer), "SET_KEY");
2417 handle_set_key (n, sm);
2422 * We received a PING message. Validate and transmit
2425 * @param n sender of the PING
2426 * @param m the encrypted PING message itself
2429 handle_ping (struct Neighbour *n, const struct PingMessage *m)
2431 struct PingMessage t;
2432 struct PingMessage *tp;
2433 struct MessageEntry *me;
2436 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2437 "Core service receives `%s' request from `%4s'.\n",
2438 "PING", GNUNET_i2s (&n->peer));
2442 &my_identity.hashPubKey,
2445 sizeof (struct PingMessage) -
2446 sizeof (struct GNUNET_MessageHeader)))
2449 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2450 "Decrypted `%s' to `%4s' with challenge %u decrypted using key %u\n",
2452 GNUNET_i2s (&t.target),
2453 ntohl (t.challenge), n->decrypt_key.crc32);
2454 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2455 "Target of `%s' request is `%4s'.\n",
2456 "PING", GNUNET_i2s (&t.target));
2458 if (0 != memcmp (&t.target,
2459 &my_identity, sizeof (struct GNUNET_PeerIdentity)))
2461 GNUNET_break_op (0);
2464 me = GNUNET_malloc (sizeof (struct MessageEntry) +
2465 sizeof (struct PingMessage));
2466 GNUNET_CONTAINER_DLL_insert_after (n->encrypted_head,
2470 me->deadline = GNUNET_TIME_relative_to_absolute (MAX_PONG_DELAY);
2471 me->priority = PONG_PRIORITY;
2472 me->size = sizeof (struct PingMessage);
2473 tp = (struct PingMessage *) &me[1];
2474 tp->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_PONG);
2475 tp->header.size = htons (sizeof (struct PingMessage));
2477 &my_identity.hashPubKey,
2480 sizeof (struct PingMessage) -
2481 sizeof (struct GNUNET_MessageHeader));
2483 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2484 "Encrypting `%s' with challenge %u using key %u\n", "PONG",
2485 ntohl (t.challenge), n->encrypt_key.crc32);
2487 /* trigger queue processing */
2488 process_encrypted_neighbour_queue (n);
2493 * We received a PONG message. Validate and update our status.
2495 * @param n sender of the PONG
2496 * @param m the encrypted PONG message itself
2499 handle_pong (struct Neighbour *n, const struct PingMessage *m)
2501 struct PingMessage t;
2502 struct ConnectNotifyMessage cnm;
2505 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2506 "Core service receives `%s' request from `%4s'.\n",
2507 "PONG", GNUNET_i2s (&n->peer));
2511 &n->peer.hashPubKey,
2514 sizeof (struct PingMessage) -
2515 sizeof (struct GNUNET_MessageHeader)))
2518 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2519 "Decrypted `%s' from `%4s' with challenge %u using key %u\n",
2521 GNUNET_i2s (&t.target),
2522 ntohl (t.challenge), n->decrypt_key.crc32);
2524 if ((0 != memcmp (&t.target,
2526 sizeof (struct GNUNET_PeerIdentity))) ||
2527 (n->ping_challenge != ntohl (t.challenge)))
2529 /* PONG malformed */
2531 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2532 "Received malformed `%s' wanted sender `%4s' with challenge %u\n",
2533 "PONG", GNUNET_i2s (&n->peer), n->ping_challenge);
2534 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2535 "Received malformed `%s' received from `%4s' with challenge %u\n",
2536 "PONG", GNUNET_i2s (&t.target), ntohl (t.challenge));
2538 GNUNET_break_op (0);
2543 case PEER_STATE_DOWN:
2544 GNUNET_break (0); /* should be impossible */
2546 case PEER_STATE_KEY_SENT:
2547 GNUNET_break (0); /* should be impossible, how did we decrypt? */
2549 case PEER_STATE_KEY_RECEIVED:
2550 n->status = PEER_STATE_KEY_CONFIRMED;
2552 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2553 "Confirmed key via `%s' message for peer `%4s'\n",
2554 "PONG", GNUNET_i2s (&n->peer));
2556 if (n->retry_set_key_task != GNUNET_SCHEDULER_NO_TASK)
2558 GNUNET_SCHEDULER_cancel (sched, n->retry_set_key_task);
2559 n->retry_set_key_task = GNUNET_SCHEDULER_NO_TASK;
2561 cnm.header.size = htons (sizeof (struct ConnectNotifyMessage));
2562 cnm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_CONNECT);
2563 cnm.distance = htonl (n->last_distance);
2564 cnm.latency = GNUNET_TIME_relative_hton (n->last_latency);
2566 send_to_all_clients (&cnm.header, GNUNET_YES, GNUNET_CORE_OPTION_SEND_CONNECT);
2567 process_encrypted_neighbour_queue (n);
2569 case PEER_STATE_KEY_CONFIRMED:
2570 /* duplicate PONG? */
2580 * We received a SET_KEY message. Validate and update
2581 * our key material and status.
2583 * @param n the neighbour from which we received message m
2584 * @param m the set key message we received
2587 handle_set_key (struct Neighbour *n, const struct SetKeyMessage *m)
2589 struct SetKeyMessage *m_cpy;
2590 struct GNUNET_TIME_Absolute t;
2591 struct GNUNET_CRYPTO_AesSessionKey k;
2592 struct PingMessage *ping;
2593 struct PingMessage *pong;
2594 enum PeerStateMachine sender_status;
2597 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2598 "Core service receives `%s' request from `%4s'.\n",
2599 "SET_KEY", GNUNET_i2s (&n->peer));
2601 if (n->public_key == NULL)
2603 if (n->pitr != NULL)
2606 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2607 "Ignoring `%s' message due to lack of public key for peer (still trying to obtain one).\n",
2613 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2614 "Lacking public key for peer, trying to obtain one (handle_set_key).\n");
2616 m_cpy = GNUNET_malloc (sizeof (struct SetKeyMessage));
2617 memcpy (m_cpy, m, sizeof (struct SetKeyMessage));
2618 /* lookup n's public key, then try again */
2619 GNUNET_assert (n->skm == NULL);
2621 n->pitr = GNUNET_PEERINFO_iterate (cfg,
2625 GNUNET_TIME_UNIT_MINUTES,
2626 &process_hello_retry_handle_set_key, n);
2629 if (0 != memcmp (&m->target,
2631 sizeof (struct GNUNET_PeerIdentity)))
2633 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2634 _("Received `%s' message that was not for me. Ignoring.\n"),
2638 if ((ntohl (m->purpose.size) !=
2639 sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
2640 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
2641 sizeof (struct GNUNET_CRYPTO_RsaEncryptedData) +
2642 sizeof (struct GNUNET_PeerIdentity)) ||
2644 GNUNET_CRYPTO_rsa_verify (GNUNET_SIGNATURE_PURPOSE_SET_KEY,
2645 &m->purpose, &m->signature, n->public_key)))
2647 /* invalid signature */
2648 GNUNET_break_op (0);
2651 t = GNUNET_TIME_absolute_ntoh (m->creation_time);
2652 if (((n->status == PEER_STATE_KEY_RECEIVED) ||
2653 (n->status == PEER_STATE_KEY_CONFIRMED)) &&
2654 (t.value < n->decrypt_key_created.value))
2656 /* this could rarely happen due to massive re-ordering of
2657 messages on the network level, but is most likely either
2658 a bug or some adversary messing with us. Report. */
2659 GNUNET_break_op (0);
2663 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Decrypting key material.\n");
2665 if ((GNUNET_CRYPTO_rsa_decrypt (my_private_key,
2668 sizeof (struct GNUNET_CRYPTO_AesSessionKey))
2669 != sizeof (struct GNUNET_CRYPTO_AesSessionKey)) ||
2670 (GNUNET_OK != GNUNET_CRYPTO_aes_check_session_key (&k)))
2672 /* failed to decrypt !? */
2673 GNUNET_break_op (0);
2678 if (n->decrypt_key_created.value != t.value)
2680 /* fresh key, reset sequence numbers */
2681 n->last_sequence_number_received = 0;
2682 n->last_packets_bitmap = 0;
2683 n->decrypt_key_created = t;
2685 sender_status = (enum PeerStateMachine) ntohl (m->sender_status);
2688 case PEER_STATE_DOWN:
2689 n->status = PEER_STATE_KEY_RECEIVED;
2691 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2692 "Responding to `%s' with my own key.\n", "SET_KEY");
2696 case PEER_STATE_KEY_SENT:
2697 case PEER_STATE_KEY_RECEIVED:
2698 n->status = PEER_STATE_KEY_RECEIVED;
2699 if ((sender_status != PEER_STATE_KEY_RECEIVED) &&
2700 (sender_status != PEER_STATE_KEY_CONFIRMED))
2703 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2704 "Responding to `%s' with my own key (other peer has status %u).\n",
2705 "SET_KEY", sender_status);
2710 case PEER_STATE_KEY_CONFIRMED:
2711 if ((sender_status != PEER_STATE_KEY_RECEIVED) &&
2712 (sender_status != PEER_STATE_KEY_CONFIRMED))
2715 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2716 "Responding to `%s' with my own key (other peer has status %u), I was already fully up.\n",
2717 "SET_KEY", sender_status);
2726 if (n->pending_ping != NULL)
2728 ping = n->pending_ping;
2729 n->pending_ping = NULL;
2730 handle_ping (n, ping);
2733 if (n->pending_pong != NULL)
2735 pong = n->pending_pong;
2736 n->pending_pong = NULL;
2737 handle_pong (n, pong);
2744 * Send a P2P message to a client.
2746 * @param sender who sent us the message?
2747 * @param client who should we give the message to?
2748 * @param m contains the message to transmit
2749 * @param msize number of bytes in buf to transmit
2752 send_p2p_message_to_client (struct Neighbour *sender,
2753 struct Client *client,
2754 const void *m, size_t msize)
2756 char buf[msize + sizeof (struct NotifyTrafficMessage)];
2757 struct NotifyTrafficMessage *ntm;
2760 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2761 "Core service passes message from `%4s' of type %u to client.\n",
2762 GNUNET_i2s(&sender->peer),
2763 ntohs (((const struct GNUNET_MessageHeader *) m)->type));
2765 ntm = (struct NotifyTrafficMessage *) buf;
2766 ntm->header.size = htons (msize + sizeof (struct NotifyTrafficMessage));
2767 ntm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_INBOUND);
2768 ntm->distance = htonl (sender->last_distance);
2769 ntm->latency = GNUNET_TIME_relative_hton (sender->last_latency);
2770 ntm->peer = sender->peer;
2771 memcpy (&ntm[1], m, msize);
2772 send_to_client (client, &ntm->header, GNUNET_YES);
2777 * Deliver P2P message to interested clients.
2779 * @param sender who sent us the message?
2780 * @param m the message
2781 * @param msize size of the message (including header)
2784 deliver_message (struct Neighbour *sender,
2785 const struct GNUNET_MessageHeader *m, size_t msize)
2787 struct Client *cpos;
2793 type = ntohs (m->type);
2795 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2796 "Received encapsulated message of type %u from `%4s'\n",
2798 GNUNET_i2s (&sender->peer));
2800 dropped = GNUNET_YES;
2802 while (cpos != NULL)
2804 deliver_full = GNUNET_NO;
2805 if (0 != (cpos->options & GNUNET_CORE_OPTION_SEND_FULL_INBOUND))
2806 deliver_full = GNUNET_YES;
2809 for (tpos = 0; tpos < cpos->tcnt; tpos++)
2811 if (type != cpos->types[tpos])
2813 deliver_full = GNUNET_YES;
2817 if (GNUNET_YES == deliver_full)
2819 send_p2p_message_to_client (sender, cpos, m, msize);
2820 dropped = GNUNET_NO;
2822 else if (cpos->options & GNUNET_CORE_OPTION_SEND_HDR_INBOUND)
2824 send_p2p_message_to_client (sender, cpos, m,
2825 sizeof (struct GNUNET_MessageHeader));
2829 if (dropped == GNUNET_YES)
2832 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2833 "Message of type %u from `%4s' not delivered to any client.\n",
2835 GNUNET_i2s (&sender->peer));
2837 /* FIXME: stats... */
2843 * Align P2P message and then deliver to interested clients.
2845 * @param sender who sent us the message?
2846 * @param buffer unaligned (!) buffer containing message
2847 * @param msize size of the message (including header)
2850 align_and_deliver (struct Neighbour *sender, const char *buffer, size_t msize)
2854 /* TODO: call to statistics? */
2855 memcpy (abuf, buffer, msize);
2856 deliver_message (sender, (const struct GNUNET_MessageHeader *) abuf, msize);
2861 * Deliver P2P messages to interested clients.
2863 * @param sender who sent us the message?
2864 * @param buffer buffer containing messages, can be modified
2865 * @param buffer_size size of the buffer (overall)
2866 * @param offset offset where messages in the buffer start
2869 deliver_messages (struct Neighbour *sender,
2870 const char *buffer, size_t buffer_size, size_t offset)
2872 struct GNUNET_MessageHeader *mhp;
2873 struct GNUNET_MessageHeader mh;
2877 while (offset + sizeof (struct GNUNET_MessageHeader) <= buffer_size)
2879 if (0 != offset % sizeof (uint16_t))
2881 /* outch, need to copy to access header */
2882 memcpy (&mh, &buffer[offset], sizeof (struct GNUNET_MessageHeader));
2887 /* can access header directly */
2888 mhp = (struct GNUNET_MessageHeader *) &buffer[offset];
2890 msize = ntohs (mhp->size);
2891 if (msize + offset > buffer_size)
2893 /* malformed message, header says it is larger than what
2894 would fit into the overall buffer */
2895 GNUNET_break_op (0);
2898 #if HAVE_UNALIGNED_64_ACCESS
2899 need_align = (0 != offset % 4) ? GNUNET_YES : GNUNET_NO;
2901 need_align = (0 != offset % 8) ? GNUNET_YES : GNUNET_NO;
2903 if (GNUNET_YES == need_align)
2904 align_and_deliver (sender, &buffer[offset], msize);
2906 deliver_message (sender,
2907 (const struct GNUNET_MessageHeader *)
2908 &buffer[offset], msize);
2915 * We received an encrypted message. Decrypt, validate and
2916 * pass on to the appropriate clients.
2919 handle_encrypted_message (struct Neighbour *n,
2920 const struct EncryptedMessage *m)
2922 size_t size = ntohs (m->header.size);
2924 struct EncryptedMessage *pt; /* plaintext */
2928 struct GNUNET_TIME_Absolute t;
2932 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2933 "Core service receives `%s' request from `%4s'.\n",
2934 "ENCRYPTED_MESSAGE", GNUNET_i2s (&n->peer));
2936 GNUNET_CRYPTO_hash (&m->iv_seed, sizeof (uint32_t), &iv);
2942 &buf[ENCRYPTED_HEADER_SIZE],
2943 size - ENCRYPTED_HEADER_SIZE))
2945 pt = (struct EncryptedMessage *) buf;
2948 GNUNET_CRYPTO_hash (&pt->sequence_number,
2949 size - ENCRYPTED_HEADER_SIZE - sizeof (GNUNET_HashCode), &ph);
2950 if (0 != memcmp (&ph,
2951 &pt->plaintext_hash,
2952 sizeof (GNUNET_HashCode)))
2954 /* checksum failed */
2955 GNUNET_break_op (0);
2959 /* validate sequence number */
2960 snum = ntohl (pt->sequence_number);
2961 if (n->last_sequence_number_received == snum)
2963 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2964 "Received duplicate message, ignoring.\n");
2965 /* duplicate, ignore */
2968 if ((n->last_sequence_number_received > snum) &&
2969 (n->last_sequence_number_received - snum > 32))
2971 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2972 "Received ancient out of sequence message, ignoring.\n");
2973 /* ancient out of sequence, ignore */
2976 if (n->last_sequence_number_received > snum)
2978 unsigned int rotbit =
2979 1 << (n->last_sequence_number_received - snum - 1);
2980 if ((n->last_packets_bitmap & rotbit) != 0)
2982 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2983 "Received duplicate message, ignoring.\n");
2984 /* duplicate, ignore */
2987 n->last_packets_bitmap |= rotbit;
2989 if (n->last_sequence_number_received < snum)
2991 n->last_packets_bitmap <<= (snum - n->last_sequence_number_received);
2992 n->last_sequence_number_received = snum;
2995 /* check timestamp */
2996 t = GNUNET_TIME_absolute_ntoh (pt->timestamp);
2997 if (GNUNET_TIME_absolute_get_duration (t).value > MAX_MESSAGE_AGE.value)
2999 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3001 ("Message received far too old (%llu ms). Content ignored.\n"),
3002 GNUNET_TIME_absolute_get_duration (t).value);
3006 /* process decrypted message(s) */
3007 update_window (GNUNET_YES,
3008 &n->available_send_window,
3009 &n->last_asw_update,
3011 n->bpm_out_external_limit = ntohl (pt->inbound_bpm_limit);
3012 n->bpm_out = GNUNET_MAX (n->bpm_out_external_limit,
3013 n->bpm_out_internal_limit);
3014 n->last_activity = GNUNET_TIME_absolute_get ();
3015 off = sizeof (struct EncryptedMessage);
3016 deliver_messages (n, buf, size, off);
3021 * Function called by the transport for each received message.
3023 * @param cls closure
3024 * @param peer (claimed) identity of the other peer
3025 * @param message the message
3026 * @param latency estimated latency for communicating with the
3027 * given peer (round-trip)
3028 * @param distance in overlay hops, as given by transport plugin
3031 handle_transport_receive (void *cls,
3032 const struct GNUNET_PeerIdentity *peer,
3033 const struct GNUNET_MessageHeader *message,
3034 struct GNUNET_TIME_Relative latency,
3035 unsigned int distance)
3037 struct Neighbour *n;
3038 struct GNUNET_TIME_Absolute now;
3044 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3045 "Received message of type %u from `%4s', demultiplexing.\n",
3046 ntohs (message->type), GNUNET_i2s (peer));
3048 n = find_neighbour (peer);
3050 n = create_neighbour (peer);
3053 n->last_latency = latency;
3054 n->last_distance = distance;
3055 up = (n->status == PEER_STATE_KEY_CONFIRMED);
3056 type = ntohs (message->type);
3057 size = ntohs (message->size);
3060 "Received message of type %u from `%4s'\n",
3066 case GNUNET_MESSAGE_TYPE_CORE_SET_KEY:
3067 if (size != sizeof (struct SetKeyMessage))
3069 GNUNET_break_op (0);
3072 handle_set_key (n, (const struct SetKeyMessage *) message);
3074 case GNUNET_MESSAGE_TYPE_CORE_ENCRYPTED_MESSAGE:
3075 if (size < sizeof (struct EncryptedMessage) +
3076 sizeof (struct GNUNET_MessageHeader))
3078 GNUNET_break_op (0);
3081 if ((n->status != PEER_STATE_KEY_RECEIVED) &&
3082 (n->status != PEER_STATE_KEY_CONFIRMED))
3084 GNUNET_break_op (0);
3087 handle_encrypted_message (n, (const struct EncryptedMessage *) message);
3089 case GNUNET_MESSAGE_TYPE_CORE_PING:
3090 if (size != sizeof (struct PingMessage))
3092 GNUNET_break_op (0);
3095 if ((n->status != PEER_STATE_KEY_RECEIVED) &&
3096 (n->status != PEER_STATE_KEY_CONFIRMED))
3099 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3100 "Core service receives `%s' request from `%4s' but have not processed key; marking as pending.\n",
3101 "PING", GNUNET_i2s (&n->peer));
3103 GNUNET_free_non_null (n->pending_ping);
3104 n->pending_ping = GNUNET_malloc (sizeof (struct PingMessage));
3105 memcpy (n->pending_ping, message, sizeof (struct PingMessage));
3108 handle_ping (n, (const struct PingMessage *) message);
3110 case GNUNET_MESSAGE_TYPE_CORE_PONG:
3111 if (size != sizeof (struct PingMessage))
3113 GNUNET_break_op (0);
3116 if ( (n->status != PEER_STATE_KEY_RECEIVED) &&
3117 (n->status != PEER_STATE_KEY_CONFIRMED) )
3120 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3121 "Core service receives `%s' request from `%4s' but have not processed key; marking as pending.\n",
3122 "PONG", GNUNET_i2s (&n->peer));
3124 GNUNET_free_non_null (n->pending_pong);
3125 n->pending_pong = GNUNET_malloc (sizeof (struct PingMessage));
3126 memcpy (n->pending_pong, message, sizeof (struct PingMessage));
3129 handle_pong (n, (const struct PingMessage *) message);
3132 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3133 _("Unsupported message of type %u received.\n"), type);
3136 if (n->status == PEER_STATE_KEY_CONFIRMED)
3138 now = GNUNET_TIME_absolute_get ();
3139 n->last_activity = now;
3141 n->time_established = now;
3147 * Function that recalculates the bandwidth quota for the
3148 * given neighbour and transmits it to the transport service.
3150 * @param cls neighbour for the quota update
3154 neighbour_quota_update (void *cls,
3155 const struct GNUNET_SCHEDULER_TaskContext *tc)
3157 struct Neighbour *n = cls;
3161 unsigned long long distributable;
3163 n->quota_update_task = GNUNET_SCHEDULER_NO_TASK;
3164 /* calculate relative preference among all neighbours;
3165 divides by a bit more to avoid division by zero AND to
3166 account for possibility of new neighbours joining any time
3167 AND to convert to double... */
3168 pref_rel = n->current_preference / (1.0 + preference_sum);
3170 if (bandwidth_target_out > neighbour_count * MIN_BPM_PER_PEER)
3171 distributable = bandwidth_target_out - neighbour_count * MIN_BPM_PER_PEER;
3172 share = distributable * pref_rel;
3173 q_in = MIN_BPM_PER_PEER + (unsigned long long) share;
3174 /* check if we want to disconnect for good due to inactivity */
3175 if ( (GNUNET_TIME_absolute_get_duration (n->last_activity).value > GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT.value) &&
3176 (GNUNET_TIME_absolute_get_duration (n->time_established).value > GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT.value) )
3179 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3180 "Forcing disconnect of `%4s' due to inactivity (?).\n",
3181 GNUNET_i2s (&n->peer));
3183 q_in = 0; /* force disconnect */
3185 if ( (n->bpm_in + MIN_BPM_CHANGE < q_in) ||
3186 (n->bpm_in - MIN_BPM_CHANGE > q_in) )
3189 GNUNET_TRANSPORT_set_quota (transport,
3193 GNUNET_TIME_UNIT_FOREVER_REL,
3196 schedule_quota_update (n);
3201 * Function called by transport to notify us that
3202 * a peer connected to us (on the network level).
3204 * @param cls closure
3205 * @param peer the peer that connected
3206 * @param latency current latency of the connection
3207 * @param distance in overlay hops, as given by transport plugin
3210 handle_transport_notify_connect (void *cls,
3211 const struct GNUNET_PeerIdentity *peer,
3212 struct GNUNET_TIME_Relative latency,
3213 unsigned int distance)
3215 struct Neighbour *n;
3216 struct GNUNET_TIME_Absolute now;
3217 struct ConnectNotifyMessage cnm;
3219 n = find_neighbour (peer);
3222 if (n->is_connected)
3224 /* duplicate connect notification!? */
3231 n = create_neighbour (peer);
3233 now = GNUNET_TIME_absolute_get ();
3234 n->is_connected = GNUNET_YES;
3235 n->last_latency = latency;
3236 n->last_distance = distance;
3237 n->last_asw_update = now;
3238 n->last_arw_update = now;
3240 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3241 "Received connection from `%4s'.\n",
3242 GNUNET_i2s (&n->peer));
3244 cnm.header.size = htons (sizeof (struct ConnectNotifyMessage));
3245 cnm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_PRE_CONNECT);
3246 cnm.distance = htonl (n->last_distance);
3247 cnm.latency = GNUNET_TIME_relative_hton (n->last_latency);
3249 send_to_all_clients (&cnm.header, GNUNET_YES, GNUNET_CORE_OPTION_SEND_PRE_CONNECT);
3255 * Function called by transport telling us that a peer
3258 * @param cls closure
3259 * @param peer the peer that disconnected
3262 handle_transport_notify_disconnect (void *cls,
3263 const struct GNUNET_PeerIdentity *peer)
3265 struct DisconnectNotifyMessage cnm;
3266 struct Neighbour *n;
3269 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3270 "Peer `%4s' disconnected from us.\n", GNUNET_i2s (peer));
3272 n = find_neighbour (peer);
3278 GNUNET_break (n->is_connected);
3279 cnm.header.size = htons (sizeof (struct DisconnectNotifyMessage));
3280 cnm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_DISCONNECT);
3282 send_to_all_clients (&cnm.header, GNUNET_YES, GNUNET_CORE_OPTION_SEND_DISCONNECT);
3283 n->is_connected = GNUNET_NO;
3288 * Last task run during shutdown. Disconnects us from
3292 cleaning_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
3294 struct Neighbour *n;
3298 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3299 "Core service shutting down.\n");
3301 GNUNET_assert (transport != NULL);
3302 GNUNET_TRANSPORT_disconnect (transport);
3304 while (NULL != (n = neighbours))
3306 neighbours = n->next;
3307 GNUNET_assert (neighbour_count > 0);
3311 GNUNET_SERVER_notification_context_destroy (notifier);
3313 while (NULL != (c = clients))
3314 handle_client_disconnect (NULL, c->client_handle);
3315 if (my_private_key != NULL)
3316 GNUNET_CRYPTO_rsa_key_free (my_private_key);
3321 * Initiate core service.
3323 * @param cls closure
3324 * @param s scheduler to use
3325 * @param serv the initialized server
3326 * @param c configuration to use
3330 struct GNUNET_SCHEDULER_Handle *s,
3331 struct GNUNET_SERVER_Handle *serv,
3332 const struct GNUNET_CONFIGURATION_Handle *c)
3335 unsigned long long qin;
3336 unsigned long long qout;
3337 unsigned long long tneigh;
3343 /* parse configuration */
3346 GNUNET_CONFIGURATION_get_value_number (c,
3349 &bandwidth_target_in)) ||
3351 GNUNET_CONFIGURATION_get_value_number (c,
3354 &bandwidth_target_out)) ||
3356 GNUNET_CONFIGURATION_get_value_filename (c,
3358 "HOSTKEY", &keyfile)))
3360 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3362 ("Core service is lacking key configuration settings. Exiting.\n"));
3363 GNUNET_SCHEDULER_shutdown (s);
3366 my_private_key = GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
3367 GNUNET_free (keyfile);
3368 if (my_private_key == NULL)
3370 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3371 _("Core service could not access hostkey. Exiting.\n"));
3372 GNUNET_SCHEDULER_shutdown (s);
3375 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &my_public_key);
3376 GNUNET_CRYPTO_hash (&my_public_key,
3377 sizeof (my_public_key), &my_identity.hashPubKey);
3378 /* setup notification */
3380 notifier = GNUNET_SERVER_notification_context_create (server,
3382 GNUNET_SERVER_disconnect_notify (server, &handle_client_disconnect, NULL);
3383 /* setup transport connection */
3384 transport = GNUNET_TRANSPORT_connect (sched,
3387 &handle_transport_receive,
3388 &handle_transport_notify_connect,
3389 &handle_transport_notify_disconnect);
3390 GNUNET_assert (NULL != transport);
3391 GNUNET_SCHEDULER_add_delayed (sched,
3392 GNUNET_TIME_UNIT_FOREVER_REL,
3393 &cleaning_task, NULL);
3394 /* process client requests */
3395 GNUNET_SERVER_add_handlers (server, handlers);
3396 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3397 _("Core service of `%4s' ready.\n"), GNUNET_i2s (&my_identity));
3403 * The main function for the transport service.
3405 * @param argc number of arguments from the command line
3406 * @param argv command line arguments
3407 * @return 0 ok, 1 on error
3410 main (int argc, char *const *argv)
3412 return (GNUNET_OK ==
3413 GNUNET_SERVICE_run (argc,
3416 GNUNET_SERVICE_OPTION_NONE,
3417 &run, NULL)) ? 0 : 1;
3420 /* end of gnunet-service-core.c */