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
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file 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) + sizeof(GNUNET_HashCode))
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;
189 uint32_t reserved GNUNET_PACKED;
192 * Hash of the plaintext, used to verify message integrity;
193 * ALSO used as the IV for the symmetric cipher! Everything
194 * after this hash will be encrypted. ENCRYPTED_HEADER_SIZE
195 * must be set to the offset of the next field.
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 linked list (for now).
301 struct MessageEntry *next;
304 * By when are we supposed to transmit this message?
306 struct GNUNET_TIME_Absolute deadline;
309 * How important is this message to us?
311 unsigned int priority;
314 * How long is the message? (number of bytes following
315 * the "struct MessageEntry", but not including the
316 * size of "struct MessageEntry" itself!)
321 * Was this message selected for transmission in the
322 * current round? GNUNET_YES or GNUNET_NO.
327 * Did we give this message some slack (delayed sending) previously
328 * (and hence should not give it any more slack)? GNUNET_YES or
339 * We keep neighbours in a linked list (for now).
341 struct Neighbour *next;
344 * Unencrypted messages destined for this peer.
346 struct MessageEntry *messages;
349 * Head of the batched, encrypted message queue (already ordered,
350 * transmit starting with the head).
352 struct MessageEntry *encrypted_head;
355 * Tail of the batched, encrypted message queue (already ordered,
356 * append new messages to tail)
358 struct MessageEntry *encrypted_tail;
361 * Handle for pending requests for transmission to this peer
362 * with the transport service. NULL if no request is pending.
364 struct GNUNET_TRANSPORT_TransmitHandle *th;
367 * Public key of the neighbour, NULL if we don't have it yet.
369 struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *public_key;
372 * We received a PING message before we got the "public_key"
373 * (or the SET_KEY). We keep it here until we have a key
374 * to decrypt it. NULL if no PING is pending.
376 struct PingMessage *pending_ping;
379 * Non-NULL if we are currently looking up HELLOs for this peer.
382 struct GNUNET_PEERINFO_IteratorContext *pitr;
385 * SetKeyMessage to transmit, NULL if we are not currently trying
388 struct SetKeyMessage *skm;
391 * Identity of the neighbour.
393 struct GNUNET_PeerIdentity peer;
396 * Key we use to encrypt our messages for the other peer
397 * (initialized by us when we do the handshake).
399 struct GNUNET_CRYPTO_AesSessionKey encrypt_key;
402 * Key we use to decrypt messages from the other peer
403 * (given to us by the other peer during the handshake).
405 struct GNUNET_CRYPTO_AesSessionKey decrypt_key;
408 * ID of task used for re-trying plaintext scheduling.
410 GNUNET_SCHEDULER_TaskIdentifier retry_plaintext_task;
413 * ID of task used for re-trying SET_KEY and PING message.
415 GNUNET_SCHEDULER_TaskIdentifier retry_set_key_task;
418 * ID of task used for updating bandwidth quota for this neighbour.
420 GNUNET_SCHEDULER_TaskIdentifier quota_update_task;
423 * At what time did we generate our encryption key?
425 struct GNUNET_TIME_Absolute encrypt_key_created;
428 * At what time did the other peer generate the decryption key?
430 struct GNUNET_TIME_Absolute decrypt_key_created;
433 * At what time did we initially establish (as in, complete session
434 * key handshake) this connection? Should be zero if status != KEY_CONFIRMED.
436 struct GNUNET_TIME_Absolute time_established;
439 * At what time did we last receive an encrypted message from the
440 * other peer? Should be zero if status != KEY_CONFIRMED.
442 struct GNUNET_TIME_Absolute last_activity;
445 * Last latency observed from this peer.
447 struct GNUNET_TIME_Relative last_latency;
450 * At what frequency are we currently re-trying SET_KEY messages?
452 struct GNUNET_TIME_Relative set_key_retry_frequency;
455 * Time of our last update to the "available_send_window".
457 struct GNUNET_TIME_Absolute last_asw_update;
460 * Time of our last update to the "available_recv_window".
462 struct GNUNET_TIME_Absolute last_arw_update;
465 * Number of bytes that we are eligible to transmit to this
466 * peer at this point. Incremented every minute by max_out_bpm,
467 * bounded by max_bpm (no back-log larger than MAX_BUF_FACT minutes,
468 * bandwidth-hogs are sampled at a frequency of about 78s!);
469 * may get negative if we have VERY high priority content.
471 long long available_send_window;
474 * How much downstream capacity of this peer has been reserved for
475 * our traffic? (Our clients can request that a certain amount of
476 * bandwidth is available for replies to them; this value is used to
477 * make sure that this reserved amount of bandwidth is actually
480 long long available_recv_window;
483 * How valueable were the messages of this peer recently?
485 unsigned long long current_preference;
488 * Bit map indicating which of the 32 sequence numbers before the last
489 * were received (good for accepting out-of-order packets and
490 * estimating reliability of the connection)
492 unsigned int last_packets_bitmap;
495 * Number of messages in the message queue for this peer.
497 unsigned int message_queue_size;
500 * last sequence number received on this connection (highest)
502 uint32_t last_sequence_number_received;
505 * last sequence number transmitted
507 uint32_t last_sequence_number_sent;
510 * Available bandwidth in for this peer (current target).
515 * Available bandwidth out for this peer (current target).
520 * Internal bandwidth limit set for this peer (initially
521 * typically set to "-1"). "bpm_out" is MAX of
522 * "bpm_out_internal_limit" and "bpm_out_external_limit".
524 uint32_t bpm_out_internal_limit;
527 * External bandwidth limit set for this peer by the
528 * peer that we are communicating with. "bpm_out" is MAX of
529 * "bpm_out_internal_limit" and "bpm_out_external_limit".
531 uint32_t bpm_out_external_limit;
534 * What was our PING challenge number (for this peer)?
536 uint32_t ping_challenge;
539 * What was the last distance to this peer as reported by the transports?
541 uint32_t last_distance;
544 * What is our connection status?
546 enum PeerStateMachine status;
552 * Data structure for each client connected to the core service.
557 * Clients are kept in a linked list.
562 * Handle for the client with the server API.
564 struct GNUNET_SERVER_Client *client_handle;
567 * Array of the types of messages this peer cares
568 * about (with "tcnt" entries). Allocated as part
569 * of this client struct, do not free!
574 * Options for messages this client cares about,
575 * see GNUNET_CORE_OPTION_ values.
580 * Number of types of incoming messages this client
581 * specifically cares about. Size of the "types" array.
591 static struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded my_public_key;
596 static struct GNUNET_PeerIdentity my_identity;
601 static struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key;
606 struct GNUNET_SCHEDULER_Handle *sched;
611 const struct GNUNET_CONFIGURATION_Handle *cfg;
616 static struct GNUNET_SERVER_Handle *server;
621 static struct GNUNET_TRANSPORT_Handle *transport;
624 * Linked list of our clients.
626 static struct Client *clients;
629 * Context for notifications we need to send to our clients.
631 static struct GNUNET_SERVER_NotificationContext *notifier;
634 * We keep neighbours in a linked list (for now).
636 static struct Neighbour *neighbours;
639 * Sum of all preferences among all neighbours.
641 static unsigned long long preference_sum;
644 * Total number of neighbours we have.
646 static unsigned int neighbour_count;
649 * How much inbound bandwidth are we supposed to be using?
651 static unsigned long long bandwidth_target_in;
654 * How much outbound bandwidth are we supposed to be using?
656 static unsigned long long bandwidth_target_out;
661 * A preference value for a neighbour was update. Update
662 * the preference sum accordingly.
664 * @param inc how much was a preference value increased?
667 update_preference_sum (unsigned long long inc)
670 unsigned long long os;
673 preference_sum += inc;
674 if (preference_sum >= os)
676 /* overflow! compensate by cutting all values in half! */
681 n->current_preference /= 2;
682 preference_sum += n->current_preference;
689 * Recalculate the number of bytes we expect to
690 * receive or transmit in a given window.
692 * @param force force an update now (even if not much time has passed)
693 * @param window pointer to the byte counter (updated)
694 * @param ts pointer to the timestamp (updated)
695 * @param bpm number of bytes per minute that should
696 * be added to the window.
699 update_window (int force,
701 struct GNUNET_TIME_Absolute *ts, unsigned int bpm)
703 struct GNUNET_TIME_Relative since;
705 since = GNUNET_TIME_absolute_get_duration (*ts);
706 if ( (force == GNUNET_NO) &&
707 (since.value < 60 * 1000) )
708 return; /* not even a minute has passed */
709 *ts = GNUNET_TIME_absolute_get ();
710 *window += (bpm * since.value) / 60 / 1000;
711 if (*window > MAX_WINDOW_TIME * bpm)
712 *window = MAX_WINDOW_TIME * bpm;
717 * Find the entry for the given neighbour.
719 * @param peer identity of the neighbour
720 * @return NULL if we are not connected, otherwise the
723 static struct Neighbour *
724 find_neighbour (const struct GNUNET_PeerIdentity *peer)
726 struct Neighbour *ret;
729 while ((ret != NULL) &&
730 (0 != memcmp (&ret->peer,
731 peer, sizeof (struct GNUNET_PeerIdentity))))
738 * Send a message to one of our clients.
740 * @param client target for the message
741 * @param msg message to transmit
742 * @param can_drop could this message be dropped if the
743 * client's queue is getting too large?
746 send_to_client (struct Client *client,
747 const struct GNUNET_MessageHeader *msg,
750 #if DEBUG_CORE_CLIENT
751 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
752 "Preparing to send message of type %u to client.\n",
755 GNUNET_SERVER_notification_context_unicast (notifier,
756 client->client_handle,
763 * Send a message to all of our current clients that have
764 * the right options set.
766 * @param msg message to multicast
767 * @param can_drop can this message be discarded if the queue is too long
768 * @param options mask to use
771 send_to_all_clients (const struct GNUNET_MessageHeader *msg,
780 if (0 != (c->options & options))
781 send_to_client (c, msg, can_drop);
788 * Handle CORE_INIT request.
791 handle_client_init (void *cls,
792 struct GNUNET_SERVER_Client *client,
793 const struct GNUNET_MessageHeader *message)
795 const struct InitMessage *im;
796 struct InitReplyMessage irm;
799 const uint16_t *types;
801 struct ConnectNotifyMessage cnm;
803 #if DEBUG_CORE_CLIENT
804 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
805 "Client connecting to core service with `%s' message\n",
808 /* check that we don't have an entry already */
812 if (client == c->client_handle)
815 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
820 msize = ntohs (message->size);
821 if (msize < sizeof (struct InitMessage))
824 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
827 GNUNET_SERVER_notification_context_add (notifier, client);
828 im = (const struct InitMessage *) message;
829 types = (const uint16_t *) &im[1];
830 msize -= sizeof (struct InitMessage);
831 c = GNUNET_malloc (sizeof (struct Client) + msize);
832 c->client_handle = client;
835 memcpy (&c[1], types, msize);
836 c->types = (uint16_t *) & c[1];
837 c->options = ntohl (im->options);
838 c->tcnt = msize / sizeof (uint16_t);
839 /* send init reply message */
840 irm.header.size = htons (sizeof (struct InitReplyMessage));
841 irm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_INIT_REPLY);
842 irm.reserved = htonl (0);
843 memcpy (&irm.publicKey,
845 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
846 #if DEBUG_CORE_CLIENT
847 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
848 "Sending `%s' message to client.\n", "INIT_REPLY");
850 send_to_client (c, &irm.header, GNUNET_NO);
851 /* notify new client about existing neighbours */
852 cnm.header.size = htons (sizeof (struct ConnectNotifyMessage));
853 cnm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_CONNECT);
857 #if DEBUG_CORE_CLIENT
858 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
859 "Sending `%s' message to client.\n", "NOTIFY_CONNECT");
861 cnm.distance = htonl (n->last_distance);
862 cnm.latency = GNUNET_TIME_relative_hton (n->last_latency);
864 send_to_client (c, &cnm.header, GNUNET_NO);
867 GNUNET_SERVER_receive_done (client, GNUNET_OK);
872 * A client disconnected, clean up.
875 * @param client identification of the client
878 handle_client_disconnect (void *cls, struct GNUNET_SERVER_Client *client)
885 #if DEBUG_CORE_CLIENT
886 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
887 "Client has disconnected from core service.\n");
893 if (client == pos->client_handle)
898 prev->next = pos->next;
905 /* client never sent INIT */
910 * Handle REQUEST_INFO request.
913 handle_client_request_info (void *cls,
914 struct GNUNET_SERVER_Client *client,
915 const struct GNUNET_MessageHeader *message)
917 const struct RequestInfoMessage *rcm;
919 struct ConfigurationInfoMessage cim;
921 unsigned long long old_preference;
922 struct GNUNET_SERVER_TransmitContext *tc;
924 #if DEBUG_CORE_CLIENT
925 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
926 "Core service receives `%s' request.\n", "REQUEST_INFO");
928 rcm = (const struct RequestInfoMessage *) message;
929 n = find_neighbour (&rcm->peer);
930 memset (&cim, 0, sizeof (cim));
931 if ((n != NULL) && (n->status == PEER_STATE_KEY_CONFIRMED))
933 update_window (GNUNET_YES,
934 &n->available_send_window,
937 n->bpm_out_internal_limit = ntohl (rcm->limit_outbound_bpm);
938 n->bpm_out = GNUNET_MAX (n->bpm_out_internal_limit,
939 n->bpm_out_external_limit);
940 reserv = ntohl (rcm->reserve_inbound);
943 n->available_recv_window += reserv;
947 update_window (GNUNET_NO,
948 &n->available_recv_window,
949 &n->last_arw_update, n->bpm_in);
950 if (n->available_recv_window < reserv)
951 reserv = n->available_recv_window;
952 n->available_recv_window -= reserv;
954 old_preference = n->current_preference;
955 n->current_preference += GNUNET_ntohll(rcm->preference_change);
956 if (old_preference > n->current_preference)
958 /* overflow; cap at maximum value */
959 n->current_preference = (unsigned long long) -1;
961 update_preference_sum (n->current_preference - old_preference);
962 cim.reserved_amount = htonl (reserv);
963 cim.bpm_in = htonl (n->bpm_in);
964 cim.bpm_out = htonl (n->bpm_out);
965 cim.preference = n->current_preference;
967 cim.header.size = htons (sizeof (struct ConfigurationInfoMessage));
968 cim.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_CONFIGURATION_INFO);
969 cim.peer = rcm->peer;
971 #if DEBUG_CORE_CLIENT
972 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
973 "Sending `%s' message to client.\n", "CONFIGURATION_INFO");
975 tc = GNUNET_SERVER_transmit_context_create (client);
976 GNUNET_SERVER_transmit_context_append_message (tc, &cim.header);
977 GNUNET_SERVER_transmit_context_run (tc,
978 GNUNET_TIME_UNIT_FOREVER_REL);
983 * Check if we have encrypted messages for the specified neighbour
984 * pending, and if so, check with the transport about sending them
987 * @param n neighbour to check.
989 static void process_encrypted_neighbour_queue (struct Neighbour *n);
993 * Function called when the transport service is ready to
994 * receive an encrypted message for the respective peer
996 * @param cls neighbour to use message from
997 * @param size number of bytes we can transmit
998 * @param buf where to copy the message
999 * @return number of bytes transmitted
1002 notify_encrypted_transmit_ready (void *cls, size_t size, void *buf)
1004 struct Neighbour *n = cls;
1005 struct MessageEntry *m;
1010 GNUNET_assert (NULL != (m = n->encrypted_head));
1011 n->encrypted_head = m->next;
1012 if (m->next == NULL)
1013 n->encrypted_tail = NULL;
1018 GNUNET_assert (size >= m->size);
1019 memcpy (cbuf, &m[1], m->size);
1021 n->available_send_window -= m->size;
1022 process_encrypted_neighbour_queue (n);
1025 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1026 "Copied message of type %u and size %u into transport buffer for `%4s'\n",
1027 ntohs (((struct GNUNET_MessageHeader *) &m[1])->type),
1028 ret, GNUNET_i2s (&n->peer));
1033 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1034 "Transmission for message of type %u and size %u failed\n",
1035 ntohs (((struct GNUNET_MessageHeader *) &m[1])->type),
1044 * Check if we have plaintext messages for the specified neighbour
1045 * pending, and if so, consider batching and encrypting them (and
1046 * then trigger processing of the encrypted queue if needed).
1048 * @param n neighbour to check.
1050 static void process_plaintext_neighbour_queue (struct Neighbour *n);
1054 * Check if we have encrypted messages for the specified neighbour
1055 * pending, and if so, check with the transport about sending them
1058 * @param n neighbour to check.
1061 process_encrypted_neighbour_queue (struct Neighbour *n)
1063 struct MessageEntry *m;
1066 return; /* request already pending */
1067 if (n->encrypted_head == NULL)
1069 /* encrypted queue empty, try plaintext instead */
1070 process_plaintext_neighbour_queue (n);
1074 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1075 "Asking transport for transmission of %u bytes to `%4s' in next %llu ms\n",
1076 n->encrypted_head->size,
1077 GNUNET_i2s (&n->peer),
1078 GNUNET_TIME_absolute_get_remaining (n->
1079 encrypted_head->deadline).
1083 GNUNET_TRANSPORT_notify_transmit_ready (transport, &n->peer,
1084 n->encrypted_head->size,
1085 n->encrypted_head->priority,
1086 GNUNET_TIME_absolute_get_remaining
1087 (n->encrypted_head->deadline),
1088 ¬ify_encrypted_transmit_ready,
1092 /* message request too large (oops) */
1094 /* discard encrypted message */
1095 GNUNET_assert (NULL != (m = n->encrypted_head));
1096 n->encrypted_head = m->next;
1097 if (m->next == NULL)
1098 n->encrypted_tail = NULL;
1100 process_encrypted_neighbour_queue (n);
1106 * Decrypt size bytes from in and write the result to out. Use the
1107 * key for inbound traffic of the given neighbour. This function does
1108 * NOT do any integrity-checks on the result.
1110 * @param n neighbour we are receiving from
1111 * @param iv initialization vector to use
1112 * @param in ciphertext
1113 * @param out plaintext
1114 * @param size size of in/out
1115 * @return GNUNET_OK on success
1118 do_decrypt (struct Neighbour *n,
1119 const GNUNET_HashCode * iv,
1120 const void *in, void *out, size_t size)
1122 if (size != (uint16_t) size)
1127 if ((n->status != PEER_STATE_KEY_RECEIVED) &&
1128 (n->status != PEER_STATE_KEY_CONFIRMED))
1130 GNUNET_break_op (0);
1131 return GNUNET_SYSERR;
1134 GNUNET_CRYPTO_aes_decrypt (in,
1138 GNUNET_CRYPTO_AesInitializationVector *) iv,
1142 return GNUNET_SYSERR;
1145 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1146 "Decrypted %u bytes from `%4s' using key %u\n",
1147 size, GNUNET_i2s (&n->peer), n->decrypt_key.crc32);
1154 * Encrypt size bytes from in and write the result to out. Use the
1155 * key for outbound traffic of the given neighbour.
1157 * @param n neighbour we are sending to
1158 * @param iv initialization vector to use
1159 * @param in ciphertext
1160 * @param out plaintext
1161 * @param size size of in/out
1162 * @return GNUNET_OK on success
1165 do_encrypt (struct Neighbour *n,
1166 const GNUNET_HashCode * iv,
1167 const void *in, void *out, size_t size)
1169 if (size != (uint16_t) size)
1174 GNUNET_assert (size ==
1175 GNUNET_CRYPTO_aes_encrypt (in,
1179 GNUNET_CRYPTO_AesInitializationVector
1182 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1183 "Encrypted %u bytes for `%4s' using key %u\n", size,
1184 GNUNET_i2s (&n->peer), n->encrypt_key.crc32);
1191 * Select messages for transmission. This heuristic uses a combination
1192 * of earliest deadline first (EDF) scheduling (with bounded horizon)
1193 * and priority-based discard (in case no feasible schedule exist) and
1194 * speculative optimization (defer any kind of transmission until
1195 * we either create a batch of significant size, 25% of max, or until
1196 * we are close to a deadline). Furthermore, when scheduling the
1197 * heuristic also packs as many messages into the batch as possible,
1198 * starting with those with the earliest deadline. Yes, this is fun.
1200 * @param n neighbour to select messages from
1201 * @param size number of bytes to select for transmission
1202 * @param retry_time set to the time when we should try again
1203 * (only valid if this function returns zero)
1204 * @return number of bytes selected, or 0 if we decided to
1205 * defer scheduling overall; in that case, retry_time is set.
1208 select_messages (struct Neighbour *n,
1209 size_t size, struct GNUNET_TIME_Relative *retry_time)
1211 struct MessageEntry *pos;
1212 struct MessageEntry *min;
1213 struct MessageEntry *last;
1214 unsigned int min_prio;
1215 struct GNUNET_TIME_Absolute t;
1216 struct GNUNET_TIME_Absolute now;
1219 unsigned long long slack; /* how long could we wait before missing deadlines? */
1221 int discard_low_prio;
1223 GNUNET_assert (NULL != n->messages);
1224 now = GNUNET_TIME_absolute_get ();
1225 /* last entry in linked list of messages processed */
1227 /* should we remove the entry with the lowest
1228 priority from consideration for scheduling at the
1230 discard_low_prio = GNUNET_YES;
1231 while (GNUNET_YES == discard_low_prio)
1235 discard_low_prio = GNUNET_NO;
1236 /* calculate number of bytes available for transmission at time "t" */
1237 update_window (GNUNET_NO,
1238 &n->available_send_window,
1239 &n->last_asw_update,
1241 avail = n->available_send_window;
1242 t = n->last_asw_update;
1243 /* how many bytes have we (hypothetically) scheduled so far */
1245 /* maximum time we can wait before transmitting anything
1246 and still make all of our deadlines */
1250 /* note that we use "*2" here because we want to look
1251 a bit further into the future; much more makes no
1252 sense since new message might be scheduled in the
1254 while ((pos != NULL) && (off < size * 2))
1256 if (pos->do_transmit == GNUNET_YES)
1258 /* already removed from consideration */
1262 if (discard_low_prio == GNUNET_NO)
1264 delta = pos->deadline.value;
1265 if (delta < t.value)
1268 delta = t.value - delta;
1269 avail += delta * n->bpm_out / 1000 / 60;
1270 if (avail < pos->size)
1272 discard_low_prio = GNUNET_YES; /* we could not schedule this one! */
1277 /* update slack, considering both its absolute deadline
1278 and relative deadlines caused by other messages
1279 with their respective load */
1280 slack = GNUNET_MIN (slack, avail / n->bpm_out);
1281 if ( (pos->deadline.value < now.value) ||
1282 (GNUNET_YES == pos->got_slack) )
1289 GNUNET_MIN (slack, pos->deadline.value - now.value);
1290 pos->got_slack = GNUNET_YES;
1296 t.value = GNUNET_MAX (pos->deadline.value, t.value);
1297 if (pos->priority <= min_prio)
1299 /* update min for discard */
1300 min_prio = pos->priority;
1305 if (discard_low_prio)
1307 GNUNET_assert (min != NULL);
1308 /* remove lowest-priority entry from consideration */
1309 min->do_transmit = GNUNET_YES; /* means: discard (for now) */
1313 /* guard against sending "tiny" messages with large headers without
1315 if ( (slack > 1000) && (size > 4 * off) )
1317 /* less than 25% of message would be filled with deadlines still
1318 being met if we delay by one second or more; so just wait for
1319 more data; but do not wait longer than 1s (since we don't want
1320 to delay messages for a really long time either). */
1321 retry_time->value = 1000;
1322 /* reset do_transmit values for next time */
1325 pos->do_transmit = GNUNET_NO;
1329 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1330 "Deferring transmission for 1s due to underfull message buffer size\n");
1334 /* select marked messages (up to size) for transmission */
1339 if ((pos->size <= size) && (pos->do_transmit == GNUNET_NO))
1341 pos->do_transmit = GNUNET_YES; /* mark for transmission */
1346 pos->do_transmit = GNUNET_NO; /* mark for not transmitting! */
1350 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1351 "Selected %u bytes of plaintext messages for transmission to `%4s'.\n",
1352 off, GNUNET_i2s (&n->peer));
1359 * Batch multiple messages into a larger buffer.
1361 * @param n neighbour to take messages from
1362 * @param buf target buffer
1363 * @param size size of buf
1364 * @param deadline set to transmission deadline for the result
1365 * @param retry_time set to the time when we should try again
1366 * (only valid if this function returns zero)
1367 * @param priority set to the priority of the batch
1368 * @return number of bytes written to buf (can be zero)
1371 batch_message (struct Neighbour *n,
1374 struct GNUNET_TIME_Absolute *deadline,
1375 struct GNUNET_TIME_Relative *retry_time,
1376 unsigned int *priority)
1378 char ntmb[GNUNET_SERVER_MAX_MESSAGE_SIZE];
1379 struct NotifyTrafficMessage *ntm = (struct NotifyTrafficMessage*) ntmb;
1380 struct MessageEntry *pos;
1381 struct MessageEntry *prev;
1382 struct MessageEntry *next;
1387 *deadline = GNUNET_TIME_UNIT_FOREVER_ABS;
1388 *retry_time = GNUNET_TIME_UNIT_FOREVER_REL;
1389 if (0 == select_messages (n, size, retry_time))
1391 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1392 "No messages selected, will try again in %llu ms\n",
1396 ntm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_OUTBOUND);
1397 ntm->distance = htonl (n->last_distance);
1398 ntm->latency = GNUNET_TIME_relative_hton (n->last_latency);
1399 ntm->peer = n->peer;
1403 while ((pos != NULL) && (size >= sizeof (struct GNUNET_MessageHeader)))
1406 if (GNUNET_YES == pos->do_transmit)
1408 GNUNET_assert (pos->size <= size);
1409 /* do notifications */
1410 /* FIXME: track if we have *any* client that wants
1411 full notifications and only do this if that is
1413 if (pos->size < GNUNET_SERVER_MAX_MESSAGE_SIZE - sizeof (struct NotifyTrafficMessage))
1415 memcpy (&ntm[1], &pos[1], pos->size);
1416 ntm->header.size = htons (sizeof (struct NotifyTrafficMessage) +
1417 sizeof (struct GNUNET_MessageHeader));
1418 send_to_all_clients (&ntm->header,
1420 GNUNET_CORE_OPTION_SEND_HDR_OUTBOUND);
1424 /* message too large for 'full' notifications, we do at
1425 least the 'hdr' type */
1428 sizeof (struct GNUNET_MessageHeader));
1430 ntm->header.size = htons (sizeof (struct NotifyTrafficMessage) +
1432 send_to_all_clients (&ntm->header,
1434 GNUNET_CORE_OPTION_SEND_FULL_OUTBOUND);
1437 "Encrypting message of type %u\n",
1438 ntohs(((struct GNUNET_MessageHeader*)&pos[1])->type));
1440 /* copy for encrypted transmission */
1441 memcpy (&buf[ret], &pos[1], pos->size);
1444 *priority += pos->priority;
1446 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1447 "Adding plaintext message with deadline %llu ms to batch\n",
1448 GNUNET_TIME_absolute_get_remaining (pos->deadline).value);
1450 deadline->value = GNUNET_MIN (deadline->value, pos->deadline.value);
1464 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1465 "Deadline for message batch is %llu ms\n",
1466 GNUNET_TIME_absolute_get_remaining (*deadline).value);
1473 * Remove messages with deadlines that have long expired from
1476 * @param n neighbour to inspect
1479 discard_expired_messages (struct Neighbour *n)
1481 struct MessageEntry *prev;
1482 struct MessageEntry *next;
1483 struct MessageEntry *pos;
1484 struct GNUNET_TIME_Absolute now;
1485 struct GNUNET_TIME_Relative delta;
1487 now = GNUNET_TIME_absolute_get ();
1493 delta = GNUNET_TIME_absolute_get_difference (pos->deadline, now);
1494 if (delta.value > PAST_EXPIRATION_DISCARD_TIME.value)
1497 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1498 "Message is %llu ms past due, discarding.\n",
1515 * Signature of the main function of a task.
1517 * @param cls closure
1518 * @param tc context information (why was this task triggered now)
1521 retry_plaintext_processing (void *cls,
1522 const struct GNUNET_SCHEDULER_TaskContext *tc)
1524 struct Neighbour *n = cls;
1526 n->retry_plaintext_task = GNUNET_SCHEDULER_NO_TASK;
1527 process_plaintext_neighbour_queue (n);
1532 * Send our key (and encrypted PING) to the other peer.
1534 * @param n the other peer
1536 static void send_key (struct Neighbour *n);
1539 * Task that will retry "send_key" if our previous attempt failed
1543 set_key_retry_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1545 struct Neighbour *n = cls;
1547 n->retry_set_key_task = GNUNET_SCHEDULER_NO_TASK;
1548 n->set_key_retry_frequency =
1549 GNUNET_TIME_relative_multiply (n->set_key_retry_frequency, 2);
1555 * Check if we have plaintext messages for the specified neighbour
1556 * pending, and if so, consider batching and encrypting them (and
1557 * then trigger processing of the encrypted queue if needed).
1559 * @param n neighbour to check.
1562 process_plaintext_neighbour_queue (struct Neighbour *n)
1564 char pbuf[MAX_ENCRYPTED_MESSAGE_SIZE]; /* plaintext */
1567 struct EncryptedMessage *em; /* encrypted message */
1568 struct EncryptedMessage *ph; /* plaintext header */
1569 struct MessageEntry *me;
1570 unsigned int priority;
1571 struct GNUNET_TIME_Absolute deadline;
1572 struct GNUNET_TIME_Relative retry_time;
1574 if (n->retry_plaintext_task != GNUNET_SCHEDULER_NO_TASK)
1576 GNUNET_SCHEDULER_cancel (sched, n->retry_plaintext_task);
1577 n->retry_plaintext_task = GNUNET_SCHEDULER_NO_TASK;
1581 case PEER_STATE_DOWN:
1584 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1585 "Not yet connected to `%4s', deferring processing of plaintext messages.\n",
1586 GNUNET_i2s(&n->peer));
1589 case PEER_STATE_KEY_SENT:
1590 if (n->retry_set_key_task == GNUNET_SCHEDULER_NO_TASK)
1591 n->retry_set_key_task
1592 = GNUNET_SCHEDULER_add_delayed (sched,
1593 n->set_key_retry_frequency,
1594 &set_key_retry_task, n);
1596 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1597 "Not yet connected to `%4s', deferring processing of plaintext messages.\n",
1598 GNUNET_i2s(&n->peer));
1601 case PEER_STATE_KEY_RECEIVED:
1602 if (n->retry_set_key_task == GNUNET_SCHEDULER_NO_TASK)
1603 n->retry_set_key_task
1604 = GNUNET_SCHEDULER_add_delayed (sched,
1605 n->set_key_retry_frequency,
1606 &set_key_retry_task, n);
1608 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1609 "Not yet connected to `%4s', deferring processing of plaintext messages.\n",
1610 GNUNET_i2s(&n->peer));
1613 case PEER_STATE_KEY_CONFIRMED:
1614 /* ready to continue */
1617 discard_expired_messages (n);
1618 if (n->messages == NULL)
1621 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1622 "Plaintext message queue for `%4s' is empty.\n",
1623 GNUNET_i2s(&n->peer));
1625 return; /* no pending messages */
1627 if (n->encrypted_head != NULL)
1630 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1631 "Encrypted message queue for `%4s' is still full, delaying plaintext processing.\n",
1632 GNUNET_i2s(&n->peer));
1634 return; /* wait for messages already encrypted to be
1637 ph = (struct EncryptedMessage *) pbuf;
1638 deadline = GNUNET_TIME_UNIT_FOREVER_ABS;
1640 used = sizeof (struct EncryptedMessage);
1641 used += batch_message (n,
1643 MAX_ENCRYPTED_MESSAGE_SIZE - used,
1644 &deadline, &retry_time, &priority);
1645 if (used == sizeof (struct EncryptedMessage))
1648 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1649 "No messages selected for transmission to `%4s' at this time, will try again later.\n",
1650 GNUNET_i2s(&n->peer));
1652 /* no messages selected for sending, try again later... */
1653 n->retry_plaintext_task =
1654 GNUNET_SCHEDULER_add_delayed (sched,
1656 &retry_plaintext_processing, n);
1659 ph->sequence_number = htonl (++n->last_sequence_number_sent);
1660 ph->inbound_bpm_limit = htonl (n->bpm_in);
1661 ph->timestamp = GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
1663 /* setup encryption message header */
1664 me = GNUNET_malloc (sizeof (struct MessageEntry) + used);
1665 me->deadline = deadline;
1666 me->priority = priority;
1668 em = (struct EncryptedMessage *) &me[1];
1669 em->header.size = htons (used);
1670 em->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_ENCRYPTED_MESSAGE);
1671 em->reserved = htonl (0);
1672 esize = used - ENCRYPTED_HEADER_SIZE;
1673 GNUNET_CRYPTO_hash (&ph->sequence_number, esize, &em->plaintext_hash);
1676 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1677 "Encrypting %u bytes of plaintext messages for `%4s' for transmission in %llums.\n",
1679 GNUNET_i2s(&n->peer),
1680 (unsigned long long) GNUNET_TIME_absolute_get_remaining (deadline).value);
1682 GNUNET_assert (GNUNET_OK ==
1684 &em->plaintext_hash,
1685 &ph->sequence_number,
1686 &em->sequence_number, esize));
1687 /* append to transmission list */
1688 if (n->encrypted_tail == NULL)
1689 n->encrypted_head = me;
1691 n->encrypted_tail->next = me;
1692 n->encrypted_tail = me;
1693 process_encrypted_neighbour_queue (n);
1698 * Handle CORE_SEND request.
1701 * @param client the client issuing the request
1702 * @param message the "struct SendMessage"
1705 handle_client_send (void *cls,
1706 struct GNUNET_SERVER_Client *client,
1707 const struct GNUNET_MessageHeader *message);
1711 * Function called to notify us that we either succeeded
1712 * or failed to connect (at the transport level) to another
1713 * peer. We should either free the message we were asked
1714 * to transmit or re-try adding it to the queue.
1716 * @param cls closure
1717 * @param size number of bytes available in buf
1718 * @param buf where the callee should write the message
1719 * @return number of bytes written to buf
1722 send_connect_continuation (void *cls, size_t size, void *buf)
1724 struct SendMessage *sm = cls;
1729 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1730 "Asked to send message to disconnected peer `%4s' and connection failed. Discarding message.\n",
1731 GNUNET_i2s (&sm->peer));
1737 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1738 "Connection to peer `%4s' succeeded, retrying original transmission request\n",
1739 GNUNET_i2s (&sm->peer));
1741 handle_client_send (NULL, NULL, &sm->header);
1748 * Handle CORE_SEND request.
1751 * @param client the client issuing the request
1752 * @param message the "struct SendMessage"
1755 handle_client_send (void *cls,
1756 struct GNUNET_SERVER_Client *client,
1757 const struct GNUNET_MessageHeader *message)
1759 const struct SendMessage *sm;
1760 struct SendMessage *smc;
1761 const struct GNUNET_MessageHeader *mh;
1762 struct Neighbour *n;
1763 struct MessageEntry *prev;
1764 struct MessageEntry *pos;
1765 struct MessageEntry *e;
1766 struct MessageEntry *min_prio_entry;
1767 struct MessageEntry *min_prio_prev;
1768 unsigned int min_prio;
1769 unsigned int queue_size;
1772 msize = ntohs (message->size);
1774 sizeof (struct SendMessage) + sizeof (struct GNUNET_MessageHeader))
1778 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1781 sm = (const struct SendMessage *) message;
1782 msize -= sizeof (struct SendMessage);
1783 mh = (const struct GNUNET_MessageHeader *) &sm[1];
1784 if (msize != ntohs (mh->size))
1788 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1791 n = find_neighbour (&sm->peer);
1795 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1796 "Core received `%s' request for `%4s', will try to establish connection within %llu ms\n",
1798 GNUNET_i2s (&sm->peer),
1799 GNUNET_TIME_absolute_get_remaining
1800 (GNUNET_TIME_absolute_ntoh(sm->deadline)).value);
1802 msize += sizeof (struct SendMessage);
1803 /* ask transport to connect to the peer */
1804 smc = GNUNET_malloc (msize);
1805 memcpy (smc, sm, msize);
1807 GNUNET_TRANSPORT_notify_transmit_ready (transport,
1810 GNUNET_TIME_absolute_get_remaining
1811 (GNUNET_TIME_absolute_ntoh
1813 &send_connect_continuation,
1816 /* transport has already a request pending for this peer! */
1818 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1819 "Dropped second message destined for `%4s' since connection is still down.\n",
1820 GNUNET_i2s(&sm->peer));
1825 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1829 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1830 "Core received `%s' request, queueing %u bytes of plaintext data for transmission to `%4s'.\n",
1833 GNUNET_i2s (&sm->peer));
1835 /* bound queue size */
1836 discard_expired_messages (n);
1837 min_prio = (unsigned int) -1;
1838 min_prio_entry = NULL;
1839 min_prio_prev = NULL;
1845 if (pos->priority < min_prio)
1847 min_prio_entry = pos;
1848 min_prio_prev = prev;
1849 min_prio = pos->priority;
1855 if (queue_size >= MAX_PEER_QUEUE_SIZE)
1858 if (ntohl(sm->priority) <= min_prio)
1860 /* discard new entry */
1862 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1863 "Queue full, discarding new request\n");
1866 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1869 /* discard "min_prio_entry" */
1871 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1872 "Queue full, discarding existing older request\n");
1874 if (min_prio_prev == NULL)
1875 n->messages = min_prio_entry->next;
1877 min_prio_prev->next = min_prio_entry->next;
1878 GNUNET_free (min_prio_entry);
1882 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1883 "Adding transmission request for `%4s' to queue\n",
1884 GNUNET_i2s (&sm->peer));
1886 e = GNUNET_malloc (sizeof (struct MessageEntry) + msize);
1887 e->deadline = GNUNET_TIME_absolute_ntoh (sm->deadline);
1888 e->priority = ntohl (sm->priority);
1890 memcpy (&e[1], mh, msize);
1892 /* insert, keep list sorted by deadline */
1895 while ((pos != NULL) && (pos->deadline.value < e->deadline.value))
1906 /* consider scheduling now */
1907 process_plaintext_neighbour_queue (n);
1909 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1914 * Handle CORE_REQUEST_CONNECT request.
1917 * @param client the client issuing the request
1918 * @param message the "struct ConnectMessage"
1921 handle_client_request_connect (void *cls,
1922 struct GNUNET_SERVER_Client *client,
1923 const struct GNUNET_MessageHeader *message)
1925 const struct ConnectMessage *cm = (const struct ConnectMessage*) message;
1926 struct Neighbour *n;
1928 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1929 n = find_neighbour (&cm->peer);
1931 return; /* already connected, or at least trying */
1933 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1934 "Core received `%s' request for `%4s', will try to establish connection\n",
1936 GNUNET_i2s (&cm->peer));
1938 /* ask transport to connect to the peer */
1939 /* FIXME: timeout zero OK? need for cancellation? */
1940 GNUNET_TRANSPORT_notify_transmit_ready (transport,
1943 GNUNET_TIME_UNIT_ZERO,
1950 * List of handlers for the messages understood by this
1953 static struct GNUNET_SERVER_MessageHandler handlers[] = {
1954 {&handle_client_init, NULL,
1955 GNUNET_MESSAGE_TYPE_CORE_INIT, 0},
1956 {&handle_client_request_info, NULL,
1957 GNUNET_MESSAGE_TYPE_CORE_REQUEST_INFO,
1958 sizeof (struct RequestInfoMessage)},
1959 {&handle_client_send, NULL,
1960 GNUNET_MESSAGE_TYPE_CORE_SEND, 0},
1961 {&handle_client_request_connect, NULL,
1962 GNUNET_MESSAGE_TYPE_CORE_REQUEST_CONNECT,
1963 sizeof (struct ConnectMessage)},
1969 * PEERINFO is giving us a HELLO for a peer. Add the public key to
1970 * the neighbour's struct and retry send_key. Or, if we did not get a
1971 * HELLO, just do nothing.
1974 * @param peer the peer for which this is the HELLO
1975 * @param hello HELLO message of that peer
1976 * @param trust amount of trust we currently have in that peer
1979 process_hello_retry_send_key (void *cls,
1980 const struct GNUNET_PeerIdentity *peer,
1981 const struct GNUNET_HELLO_Message *hello,
1984 struct Neighbour *n = cls;
1989 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1990 "Entered `process_hello_retry_send_key' and `peer' is NULL!\n");
1993 if (n->public_key != NULL)
1999 if (GNUNET_SCHEDULER_NO_TASK == n->retry_set_key_task)
2000 n->retry_set_key_task
2001 = GNUNET_SCHEDULER_add_delayed (sched,
2002 n->set_key_retry_frequency,
2003 &set_key_retry_task, n);
2009 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2010 "process_hello_retry_send_key for peer %s\n",
2013 if (n->public_key != NULL)
2016 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2017 "already have public key for peer %s!! (so why are we here?)\n",
2024 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2025 "Received new `%s' message for `%4s', initiating key exchange.\n",
2030 GNUNET_malloc (sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
2031 if (GNUNET_OK != GNUNET_HELLO_get_key (hello, n->public_key))
2033 GNUNET_free (n->public_key);
2034 n->public_key = NULL;
2036 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2037 "GNUNET_HELLO_get_key returned awfully\n");
2045 * Send our key (and encrypted PING) to the other peer.
2047 * @param n the other peer
2050 send_key (struct Neighbour *n)
2052 struct SetKeyMessage *sm;
2053 struct MessageEntry *me;
2054 struct PingMessage pp;
2055 struct PingMessage *pm;
2057 if ( (n->retry_set_key_task != GNUNET_SCHEDULER_NO_TASK) ||
2061 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2062 "Key exchange in progress with `%4s'.\n",
2063 GNUNET_i2s (&n->peer));
2065 return; /* already in progress */
2069 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2070 "Asked to perform key exchange with `%4s'.\n",
2071 GNUNET_i2s (&n->peer));
2073 if (n->public_key == NULL)
2075 /* lookup n's public key, then try again */
2077 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2078 "Lacking public key for `%4s', trying to obtain one (send_key).\n",
2079 GNUNET_i2s (&n->peer));
2081 GNUNET_assert (n->pitr == NULL);
2083 n->pitr = GNUNET_PEERINFO_iterate (cfg,
2087 GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 20),
2088 &process_hello_retry_send_key, n);
2091 /* first, set key message */
2092 me = GNUNET_malloc (sizeof (struct MessageEntry) +
2093 sizeof (struct SetKeyMessage));
2094 me->deadline = GNUNET_TIME_relative_to_absolute (MAX_SET_KEY_DELAY);
2095 me->priority = SET_KEY_PRIORITY;
2096 me->size = sizeof (struct SetKeyMessage);
2097 if (n->encrypted_head == NULL)
2098 n->encrypted_head = me;
2100 n->encrypted_tail->next = me;
2101 n->encrypted_tail = me;
2102 sm = (struct SetKeyMessage *) &me[1];
2103 sm->header.size = htons (sizeof (struct SetKeyMessage));
2104 sm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_SET_KEY);
2105 sm->sender_status = htonl ((int32_t) ((n->status == PEER_STATE_DOWN) ?
2106 PEER_STATE_KEY_SENT : n->status));
2108 htonl (sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
2109 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
2110 sizeof (struct GNUNET_CRYPTO_RsaEncryptedData) +
2111 sizeof (struct GNUNET_PeerIdentity));
2112 sm->purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_SET_KEY);
2113 sm->creation_time = GNUNET_TIME_absolute_hton (n->encrypt_key_created);
2114 sm->target = n->peer;
2115 GNUNET_assert (GNUNET_OK ==
2116 GNUNET_CRYPTO_rsa_encrypt (&n->encrypt_key,
2118 GNUNET_CRYPTO_AesSessionKey),
2120 &sm->encrypted_key));
2121 GNUNET_assert (GNUNET_OK ==
2122 GNUNET_CRYPTO_rsa_sign (my_private_key, &sm->purpose,
2125 /* second, encrypted PING message */
2126 me = GNUNET_malloc (sizeof (struct MessageEntry) +
2127 sizeof (struct PingMessage));
2128 me->deadline = GNUNET_TIME_relative_to_absolute (MAX_PING_DELAY);
2129 me->priority = PING_PRIORITY;
2130 me->size = sizeof (struct PingMessage);
2131 n->encrypted_tail->next = me;
2132 n->encrypted_tail = me;
2133 pm = (struct PingMessage *) &me[1];
2134 pm->header.size = htons (sizeof (struct PingMessage));
2135 pm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_PING);
2136 pp.challenge = htonl (n->ping_challenge);
2137 pp.target = n->peer;
2139 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2140 "Encrypting `%s' and `%s' messages for `%4s'.\n",
2141 "SET_KEY", "PING", GNUNET_i2s (&n->peer));
2142 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2143 "Sending `%s' to `%4s' with challenge %u encrypted using key %u\n",
2145 GNUNET_i2s (&n->peer), n->ping_challenge, n->encrypt_key.crc32);
2148 &n->peer.hashPubKey,
2151 sizeof (struct PingMessage) -
2152 sizeof (struct GNUNET_MessageHeader));
2156 case PEER_STATE_DOWN:
2157 n->status = PEER_STATE_KEY_SENT;
2159 case PEER_STATE_KEY_SENT:
2161 case PEER_STATE_KEY_RECEIVED:
2163 case PEER_STATE_KEY_CONFIRMED:
2170 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2171 "Have %llu ms left for `%s' transmission.\n",
2172 (unsigned long long) GNUNET_TIME_absolute_get_remaining (me->deadline).value,
2175 /* trigger queue processing */
2176 process_encrypted_neighbour_queue (n);
2177 if ( (n->status != PEER_STATE_KEY_CONFIRMED) &&
2178 (GNUNET_SCHEDULER_NO_TASK == n->retry_set_key_task) )
2179 n->retry_set_key_task
2180 = GNUNET_SCHEDULER_add_delayed (sched,
2181 n->set_key_retry_frequency,
2182 &set_key_retry_task, n);
2187 * We received a SET_KEY message. Validate and update
2188 * our key material and status.
2190 * @param n the neighbour from which we received message m
2191 * @param m the set key message we received
2194 handle_set_key (struct Neighbour *n, const struct SetKeyMessage *m);
2198 * PEERINFO is giving us a HELLO for a peer. Add the public key to
2199 * the neighbour's struct and retry handling the set_key message. Or,
2200 * if we did not get a HELLO, just free the set key message.
2202 * @param cls pointer to the set key message
2203 * @param peer the peer for which this is the HELLO
2204 * @param hello HELLO message of that peer
2205 * @param trust amount of trust we currently have in that peer
2208 process_hello_retry_handle_set_key (void *cls,
2209 const struct GNUNET_PeerIdentity *peer,
2210 const struct GNUNET_HELLO_Message *hello,
2213 struct Neighbour *n = cls;
2214 struct SetKeyMessage *sm = n->skm;
2223 if (n->public_key != NULL)
2224 return; /* multiple HELLOs match!? */
2226 GNUNET_malloc (sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded));
2227 if (GNUNET_OK != GNUNET_HELLO_get_key (hello, n->public_key))
2229 GNUNET_break_op (0);
2230 GNUNET_free (n->public_key);
2231 n->public_key = NULL;
2235 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2236 "Received `%s' for `%4s', continuing processing of `%s' message.\n",
2237 "HELLO", GNUNET_i2s (peer), "SET_KEY");
2239 handle_set_key (n, sm);
2244 * We received a PING message. Validate and transmit
2247 * @param n sender of the PING
2248 * @param m the encrypted PING message itself
2251 handle_ping (struct Neighbour *n, const struct PingMessage *m)
2253 struct PingMessage t;
2254 struct PingMessage *tp;
2255 struct MessageEntry *me;
2258 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2259 "Core service receives `%s' request from `%4s'.\n",
2260 "PING", GNUNET_i2s (&n->peer));
2264 &my_identity.hashPubKey,
2267 sizeof (struct PingMessage) -
2268 sizeof (struct GNUNET_MessageHeader)))
2271 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2272 "Decrypted `%s' to `%4s' with challenge %u decrypted using key %u\n",
2274 GNUNET_i2s (&t.target),
2275 ntohl (t.challenge), n->decrypt_key.crc32);
2276 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2277 "Target of `%s' request is `%4s'.\n",
2278 "PING", GNUNET_i2s (&t.target));
2280 if (0 != memcmp (&t.target,
2281 &my_identity, sizeof (struct GNUNET_PeerIdentity)))
2283 GNUNET_break_op (0);
2286 me = GNUNET_malloc (sizeof (struct MessageEntry) +
2287 sizeof (struct PingMessage));
2288 if (n->encrypted_tail != NULL)
2289 n->encrypted_tail->next = me;
2292 n->encrypted_tail = me;
2293 n->encrypted_head = me;
2295 me->deadline = GNUNET_TIME_relative_to_absolute (MAX_PONG_DELAY);
2296 me->priority = PONG_PRIORITY;
2297 me->size = sizeof (struct PingMessage);
2298 tp = (struct PingMessage *) &me[1];
2299 tp->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_PONG);
2300 tp->header.size = htons (sizeof (struct PingMessage));
2302 &my_identity.hashPubKey,
2305 sizeof (struct PingMessage) -
2306 sizeof (struct GNUNET_MessageHeader));
2308 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2309 "Encrypting `%s' with challenge %u using key %u\n", "PONG",
2310 ntohl (t.challenge), n->encrypt_key.crc32);
2312 /* trigger queue processing */
2313 process_encrypted_neighbour_queue (n);
2318 * We received a SET_KEY message. Validate and update
2319 * our key material and status.
2321 * @param n the neighbour from which we received message m
2322 * @param m the set key message we received
2325 handle_set_key (struct Neighbour *n, const struct SetKeyMessage *m)
2327 struct SetKeyMessage *m_cpy;
2328 struct GNUNET_TIME_Absolute t;
2329 struct GNUNET_CRYPTO_AesSessionKey k;
2330 struct PingMessage *ping;
2331 enum PeerStateMachine sender_status;
2334 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2335 "Core service receives `%s' request from `%4s'.\n",
2336 "SET_KEY", GNUNET_i2s (&n->peer));
2338 if (n->public_key == NULL)
2340 if (n->pitr != NULL)
2343 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2344 "Ignoring `%s' message due to lack of public key for peer (still trying to obtain one).\n",
2350 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2351 "Lacking public key for peer, trying to obtain one (handle_set_key).\n");
2353 m_cpy = GNUNET_malloc (sizeof (struct SetKeyMessage));
2354 memcpy (m_cpy, m, sizeof (struct SetKeyMessage));
2355 /* lookup n's public key, then try again */
2356 GNUNET_assert (n->skm == NULL);
2358 n->pitr = GNUNET_PEERINFO_iterate (cfg,
2362 GNUNET_TIME_UNIT_MINUTES,
2363 &process_hello_retry_handle_set_key, n);
2366 if (0 != memcmp (&m->target,
2368 sizeof (struct GNUNET_PeerIdentity)))
2370 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2371 _("Received `%s' message that was not for me. Ignoring.\n"),
2375 if ((ntohl (m->purpose.size) !=
2376 sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
2377 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
2378 sizeof (struct GNUNET_CRYPTO_RsaEncryptedData) +
2379 sizeof (struct GNUNET_PeerIdentity)) ||
2381 GNUNET_CRYPTO_rsa_verify (GNUNET_SIGNATURE_PURPOSE_SET_KEY,
2382 &m->purpose, &m->signature, n->public_key)))
2384 /* invalid signature */
2385 GNUNET_break_op (0);
2388 t = GNUNET_TIME_absolute_ntoh (m->creation_time);
2389 if (((n->status == PEER_STATE_KEY_RECEIVED) ||
2390 (n->status == PEER_STATE_KEY_CONFIRMED)) &&
2391 (t.value < n->decrypt_key_created.value))
2393 /* this could rarely happen due to massive re-ordering of
2394 messages on the network level, but is most likely either
2395 a bug or some adversary messing with us. Report. */
2396 GNUNET_break_op (0);
2400 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Decrypting key material.\n");
2402 if ((GNUNET_CRYPTO_rsa_decrypt (my_private_key,
2405 sizeof (struct GNUNET_CRYPTO_AesSessionKey))
2406 != sizeof (struct GNUNET_CRYPTO_AesSessionKey)) ||
2407 (GNUNET_OK != GNUNET_CRYPTO_aes_check_session_key (&k)))
2409 /* failed to decrypt !? */
2410 GNUNET_break_op (0);
2415 if (n->decrypt_key_created.value != t.value)
2417 /* fresh key, reset sequence numbers */
2418 n->last_sequence_number_received = 0;
2419 n->last_packets_bitmap = 0;
2420 n->decrypt_key_created = t;
2422 sender_status = (enum PeerStateMachine) ntohl (m->sender_status);
2425 case PEER_STATE_DOWN:
2426 n->status = PEER_STATE_KEY_RECEIVED;
2428 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2429 "Responding to `%s' with my own key.\n", "SET_KEY");
2433 case PEER_STATE_KEY_SENT:
2434 case PEER_STATE_KEY_RECEIVED:
2435 n->status = PEER_STATE_KEY_RECEIVED;
2436 if ((sender_status != PEER_STATE_KEY_RECEIVED) &&
2437 (sender_status != PEER_STATE_KEY_CONFIRMED))
2440 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2441 "Responding to `%s' with my own key (other peer has status %u).\n",
2442 "SET_KEY", sender_status);
2447 case PEER_STATE_KEY_CONFIRMED:
2448 if ((sender_status != PEER_STATE_KEY_RECEIVED) &&
2449 (sender_status != PEER_STATE_KEY_CONFIRMED))
2452 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2453 "Responding to `%s' with my own key (other peer has status %u), I was already fully up.\n",
2454 "SET_KEY", sender_status);
2463 if (n->pending_ping != NULL)
2465 ping = n->pending_ping;
2466 n->pending_ping = NULL;
2467 handle_ping (n, ping);
2474 * We received a PONG message. Validate and update our status.
2476 * @param n sender of the PONG
2477 * @param m the encrypted PONG message itself
2480 handle_pong (struct Neighbour *n, const struct PingMessage *m)
2482 struct PingMessage t;
2483 struct ConnectNotifyMessage cnm;
2486 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2487 "Core service receives `%s' request from `%4s'.\n",
2488 "PONG", GNUNET_i2s (&n->peer));
2492 &n->peer.hashPubKey,
2495 sizeof (struct PingMessage) -
2496 sizeof (struct GNUNET_MessageHeader)))
2499 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2500 "Decrypted `%s' from `%4s' with challenge %u using key %u\n",
2502 GNUNET_i2s (&t.target),
2503 ntohl (t.challenge), n->decrypt_key.crc32);
2505 if ((0 != memcmp (&t.target,
2507 sizeof (struct GNUNET_PeerIdentity))) ||
2508 (n->ping_challenge != ntohl (t.challenge)))
2510 /* PONG malformed */
2512 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2513 "Received malformed `%s' wanted sender `%4s' with challenge %u\n",
2514 "PONG", GNUNET_i2s (&n->peer), n->ping_challenge);
2515 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2516 "Received malformed `%s' received from `%4s' with challenge %u\n",
2517 "PONG", GNUNET_i2s (&t.target), ntohl (t.challenge));
2519 GNUNET_break_op (0);
2524 case PEER_STATE_DOWN:
2525 GNUNET_break (0); /* should be impossible */
2527 case PEER_STATE_KEY_SENT:
2528 GNUNET_break (0); /* should be impossible, how did we decrypt? */
2530 case PEER_STATE_KEY_RECEIVED:
2531 n->status = PEER_STATE_KEY_CONFIRMED;
2533 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2534 "Confirmed key via %s for peer %s\n",
2535 "PONG", GNUNET_i2s (&n->peer));
2537 if (n->retry_set_key_task != GNUNET_SCHEDULER_NO_TASK)
2539 GNUNET_SCHEDULER_cancel (sched, n->retry_set_key_task);
2540 n->retry_set_key_task = GNUNET_SCHEDULER_NO_TASK;
2542 cnm.header.size = htons (sizeof (struct ConnectNotifyMessage));
2543 cnm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_CONNECT);
2544 cnm.distance = htonl (n->last_distance);
2545 cnm.latency = GNUNET_TIME_relative_hton (n->last_latency);
2547 send_to_all_clients (&cnm.header, GNUNET_YES, GNUNET_CORE_OPTION_SEND_CONNECT);
2548 process_encrypted_neighbour_queue (n);
2550 case PEER_STATE_KEY_CONFIRMED:
2551 /* duplicate PONG? */
2561 * Send a P2P message to a client.
2563 * @param sender who sent us the message?
2564 * @param client who should we give the message to?
2565 * @param m contains the message to transmit
2566 * @param msize number of bytes in buf to transmit
2569 send_p2p_message_to_client (struct Neighbour *sender,
2570 struct Client *client,
2571 const void *m, size_t msize)
2573 char buf[msize + sizeof (struct NotifyTrafficMessage)];
2574 struct NotifyTrafficMessage *ntm;
2577 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2578 "Core service passes message from `%4s' of type %u to client.\n",
2579 GNUNET_i2s(&sender->peer),
2580 ntohs (((const struct GNUNET_MessageHeader *) m)->type));
2582 ntm = (struct NotifyTrafficMessage *) buf;
2583 ntm->header.size = htons (msize + sizeof (struct NotifyTrafficMessage));
2584 ntm->header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_INBOUND);
2585 ntm->distance = htonl (sender->last_distance);
2586 ntm->latency = GNUNET_TIME_relative_hton (sender->last_latency);
2587 ntm->peer = sender->peer;
2588 memcpy (&ntm[1], m, msize);
2589 send_to_client (client, &ntm->header, GNUNET_YES);
2594 * Deliver P2P message to interested clients.
2596 * @param sender who sent us the message?
2597 * @param m the message
2598 * @param msize size of the message (including header)
2601 deliver_message (struct Neighbour *sender,
2602 const struct GNUNET_MessageHeader *m, size_t msize)
2604 struct Client *cpos;
2609 type = ntohs (m->type);
2612 "Received encapsulated message of type %u from `%4s'\n",
2614 GNUNET_i2s (&sender->peer));
2617 while (cpos != NULL)
2619 deliver_full = GNUNET_NO;
2620 if (0 != (cpos->options & GNUNET_CORE_OPTION_SEND_FULL_INBOUND))
2621 deliver_full = GNUNET_YES;
2624 for (tpos = 0; tpos < cpos->tcnt; tpos++)
2626 if (type != cpos->types[tpos])
2628 deliver_full = GNUNET_YES;
2632 if (GNUNET_YES == deliver_full)
2633 send_p2p_message_to_client (sender, cpos, m, msize);
2634 else if (cpos->options & GNUNET_CORE_OPTION_SEND_HDR_INBOUND)
2635 send_p2p_message_to_client (sender, cpos, m,
2636 sizeof (struct GNUNET_MessageHeader));
2643 * Align P2P message and then deliver to interested clients.
2645 * @param sender who sent us the message?
2646 * @param buffer unaligned (!) buffer containing message
2647 * @param msize size of the message (including header)
2650 align_and_deliver (struct Neighbour *sender, const char *buffer, size_t msize)
2654 /* TODO: call to statistics? */
2655 memcpy (abuf, buffer, msize);
2656 deliver_message (sender, (const struct GNUNET_MessageHeader *) abuf, msize);
2661 * Deliver P2P messages to interested clients.
2663 * @param sender who sent us the message?
2664 * @param buffer buffer containing messages, can be modified
2665 * @param buffer_size size of the buffer (overall)
2666 * @param offset offset where messages in the buffer start
2669 deliver_messages (struct Neighbour *sender,
2670 const char *buffer, size_t buffer_size, size_t offset)
2672 struct GNUNET_MessageHeader *mhp;
2673 struct GNUNET_MessageHeader mh;
2677 while (offset + sizeof (struct GNUNET_MessageHeader) <= buffer_size)
2679 if (0 != offset % sizeof (uint16_t))
2681 /* outch, need to copy to access header */
2682 memcpy (&mh, &buffer[offset], sizeof (struct GNUNET_MessageHeader));
2687 /* can access header directly */
2688 mhp = (struct GNUNET_MessageHeader *) &buffer[offset];
2690 msize = ntohs (mhp->size);
2691 if (msize + offset > buffer_size)
2693 /* malformed message, header says it is larger than what
2694 would fit into the overall buffer */
2695 GNUNET_break_op (0);
2698 #if HAVE_UNALIGNED_64_ACCESS
2699 need_align = (0 != offset % 4) ? GNUNET_YES : GNUNET_NO;
2701 need_align = (0 != offset % 8) ? GNUNET_YES : GNUNET_NO;
2703 if (GNUNET_YES == need_align)
2704 align_and_deliver (sender, &buffer[offset], msize);
2706 deliver_message (sender,
2707 (const struct GNUNET_MessageHeader *)
2708 &buffer[offset], msize);
2715 * We received an encrypted message. Decrypt, validate and
2716 * pass on to the appropriate clients.
2719 handle_encrypted_message (struct Neighbour *n,
2720 const struct EncryptedMessage *m)
2722 size_t size = ntohs (m->header.size);
2724 struct EncryptedMessage *pt; /* plaintext */
2728 struct GNUNET_TIME_Absolute t;
2731 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2732 "Core service receives `%s' request from `%4s'.\n",
2733 "ENCRYPTED_MESSAGE", GNUNET_i2s (&n->peer));
2739 &m->sequence_number,
2740 &buf[ENCRYPTED_HEADER_SIZE], size - ENCRYPTED_HEADER_SIZE))
2742 pt = (struct EncryptedMessage *) buf;
2745 GNUNET_CRYPTO_hash (&pt->sequence_number,
2746 size - ENCRYPTED_HEADER_SIZE, &ph);
2747 if (0 != memcmp (&ph, &m->plaintext_hash, sizeof (GNUNET_HashCode)))
2749 /* checksum failed */
2750 GNUNET_break_op (0);
2754 /* validate sequence number */
2755 snum = ntohl (pt->sequence_number);
2756 if (n->last_sequence_number_received == snum)
2758 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2759 "Received duplicate message, ignoring.\n");
2760 /* duplicate, ignore */
2763 if ((n->last_sequence_number_received > snum) &&
2764 (n->last_sequence_number_received - snum > 32))
2766 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2767 "Received ancient out of sequence message, ignoring.\n");
2768 /* ancient out of sequence, ignore */
2771 if (n->last_sequence_number_received > snum)
2773 unsigned int rotbit =
2774 1 << (n->last_sequence_number_received - snum - 1);
2775 if ((n->last_packets_bitmap & rotbit) != 0)
2777 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2778 "Received duplicate message, ignoring.\n");
2779 /* duplicate, ignore */
2782 n->last_packets_bitmap |= rotbit;
2784 if (n->last_sequence_number_received < snum)
2786 n->last_packets_bitmap <<= (snum - n->last_sequence_number_received);
2787 n->last_sequence_number_received = snum;
2790 /* check timestamp */
2791 t = GNUNET_TIME_absolute_ntoh (pt->timestamp);
2792 if (GNUNET_TIME_absolute_get_duration (t).value > MAX_MESSAGE_AGE.value)
2794 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2796 ("Message received far too old (%llu ms). Content ignored.\n"),
2797 GNUNET_TIME_absolute_get_duration (t).value);
2801 /* process decrypted message(s) */
2802 update_window (GNUNET_YES,
2803 &n->available_send_window,
2804 &n->last_asw_update,
2806 n->bpm_out_external_limit = ntohl (pt->inbound_bpm_limit);
2807 n->bpm_out = GNUNET_MAX (n->bpm_out_external_limit,
2808 n->bpm_out_internal_limit);
2809 n->last_activity = GNUNET_TIME_absolute_get ();
2810 off = sizeof (struct EncryptedMessage);
2811 deliver_messages (n, buf, size, off);
2816 * Function called by the transport for each received message.
2818 * @param cls closure
2819 * @param peer (claimed) identity of the other peer
2820 * @param message the message
2821 * @param latency estimated latency for communicating with the
2822 * given peer (round-trip)
2823 * @param distance in overlay hops, as given by transport plugin
2826 handle_transport_receive (void *cls,
2827 const struct GNUNET_PeerIdentity *peer,
2828 const struct GNUNET_MessageHeader *message,
2829 struct GNUNET_TIME_Relative latency,
2830 unsigned int distance)
2832 struct Neighbour *n;
2833 struct GNUNET_TIME_Absolute now;
2839 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2840 "Received message of type %u from `%4s', demultiplexing.\n",
2841 ntohs (message->type), GNUNET_i2s (peer));
2843 n = find_neighbour (peer);
2849 n->last_latency = latency;
2850 n->last_distance = distance;
2851 up = (n->status == PEER_STATE_KEY_CONFIRMED);
2852 type = ntohs (message->type);
2853 size = ntohs (message->size);
2856 "Received message of type %u from `%4s'\n",
2862 case GNUNET_MESSAGE_TYPE_CORE_SET_KEY:
2863 if (size != sizeof (struct SetKeyMessage))
2865 GNUNET_break_op (0);
2868 handle_set_key (n, (const struct SetKeyMessage *) message);
2870 case GNUNET_MESSAGE_TYPE_CORE_ENCRYPTED_MESSAGE:
2871 if (size < sizeof (struct EncryptedMessage) +
2872 sizeof (struct GNUNET_MessageHeader))
2874 GNUNET_break_op (0);
2877 if ((n->status != PEER_STATE_KEY_RECEIVED) &&
2878 (n->status != PEER_STATE_KEY_CONFIRMED))
2880 GNUNET_break_op (0);
2883 handle_encrypted_message (n, (const struct EncryptedMessage *) message);
2885 case GNUNET_MESSAGE_TYPE_CORE_PING:
2886 if (size != sizeof (struct PingMessage))
2888 GNUNET_break_op (0);
2891 if ((n->status != PEER_STATE_KEY_RECEIVED) &&
2892 (n->status != PEER_STATE_KEY_CONFIRMED))
2895 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2896 "Core service receives `%s' request from `%4s' but have not processed key; marking as pending.\n",
2897 "PING", GNUNET_i2s (&n->peer));
2899 GNUNET_free_non_null (n->pending_ping);
2900 n->pending_ping = GNUNET_malloc (sizeof (struct PingMessage));
2901 memcpy (n->pending_ping, message, sizeof (struct PingMessage));
2904 handle_ping (n, (const struct PingMessage *) message);
2906 case GNUNET_MESSAGE_TYPE_CORE_PONG:
2907 if (size != sizeof (struct PingMessage))
2909 GNUNET_break_op (0);
2912 if ((n->status != PEER_STATE_KEY_SENT) &&
2913 (n->status != PEER_STATE_KEY_RECEIVED) &&
2914 (n->status != PEER_STATE_KEY_CONFIRMED))
2916 /* could not decrypt pong, oops! */
2917 GNUNET_break_op (0);
2920 handle_pong (n, (const struct PingMessage *) message);
2923 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2924 _("Unsupported message of type %u received.\n"), type);
2927 if (n->status == PEER_STATE_KEY_CONFIRMED)
2929 now = GNUNET_TIME_absolute_get ();
2930 n->last_activity = now;
2932 n->time_established = now;
2938 * Function that recalculates the bandwidth quota for the
2939 * given neighbour and transmits it to the transport service.
2941 * @param cls neighbour for the quota update
2945 neighbour_quota_update (void *cls,
2946 const struct GNUNET_SCHEDULER_TaskContext *tc);
2950 * Schedule the task that will recalculate the bandwidth
2951 * quota for this peer (and possibly force a disconnect of
2952 * idle peers by calculating a bandwidth of zero).
2955 schedule_quota_update (struct Neighbour *n)
2957 GNUNET_assert (n->quota_update_task ==
2958 GNUNET_SCHEDULER_NO_TASK);
2959 n->quota_update_task
2960 = GNUNET_SCHEDULER_add_delayed (sched,
2961 QUOTA_UPDATE_FREQUENCY,
2962 &neighbour_quota_update,
2968 * Function that recalculates the bandwidth quota for the
2969 * given neighbour and transmits it to the transport service.
2971 * @param cls neighbour for the quota update
2975 neighbour_quota_update (void *cls,
2976 const struct GNUNET_SCHEDULER_TaskContext *tc)
2978 struct Neighbour *n = cls;
2982 unsigned long long distributable;
2984 n->quota_update_task = GNUNET_SCHEDULER_NO_TASK;
2985 /* calculate relative preference among all neighbours;
2986 divides by a bit more to avoid division by zero AND to
2987 account for possibility of new neighbours joining any time
2988 AND to convert to double... */
2989 pref_rel = n->current_preference / (1.0 + preference_sum);
2991 if (bandwidth_target_out > neighbour_count * MIN_BPM_PER_PEER)
2992 distributable = bandwidth_target_out - neighbour_count * MIN_BPM_PER_PEER;
2993 share = distributable * pref_rel;
2994 q_in = MIN_BPM_PER_PEER + (unsigned long long) share;
2995 /* check if we want to disconnect for good due to inactivity */
2996 if ( (GNUNET_TIME_absolute_get_duration (n->last_activity).value > GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT.value) &&
2997 (GNUNET_TIME_absolute_get_duration (n->time_established).value > GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT.value) )
3000 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3001 "Forcing disconnect of `%4s' due to inactivity (?).\n",
3002 GNUNET_i2s (&n->peer));
3004 q_in = 0; /* force disconnect */
3006 if ( (n->bpm_in + MIN_BPM_CHANGE < q_in) ||
3007 (n->bpm_in - MIN_BPM_CHANGE > q_in) )
3010 GNUNET_TRANSPORT_set_quota (transport,
3014 GNUNET_TIME_UNIT_FOREVER_REL,
3017 schedule_quota_update (n);
3022 * Function called by transport to notify us that
3023 * a peer connected to us (on the network level).
3025 * @param cls closure
3026 * @param peer the peer that connected
3027 * @param latency current latency of the connection
3028 * @param distance in overlay hops, as given by transport plugin
3031 handle_transport_notify_connect (void *cls,
3032 const struct GNUNET_PeerIdentity *peer,
3033 struct GNUNET_TIME_Relative latency,
3034 unsigned int distance)
3036 struct Neighbour *n;
3037 struct GNUNET_TIME_Absolute now;
3038 struct ConnectNotifyMessage cnm;
3040 n = find_neighbour (peer);
3043 /* duplicate connect notification!? */
3047 now = GNUNET_TIME_absolute_get ();
3048 n = GNUNET_malloc (sizeof (struct Neighbour));
3049 n->next = neighbours;
3053 n->last_latency = latency;
3054 n->last_distance = distance;
3055 GNUNET_CRYPTO_aes_create_session_key (&n->encrypt_key);
3056 n->encrypt_key_created = now;
3057 n->set_key_retry_frequency = INITIAL_SET_KEY_RETRY_FREQUENCY;
3058 n->last_activity = now;
3059 n->last_asw_update = now;
3060 n->last_arw_update = now;
3061 n->bpm_in = GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT;
3062 n->bpm_out = GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT;
3063 n->bpm_out_internal_limit = (uint32_t) - 1;
3064 n->bpm_out_external_limit = GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT;
3065 n->ping_challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
3068 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3069 "Received connection from `%4s'.\n",
3070 GNUNET_i2s (&n->peer));
3072 schedule_quota_update (n);
3073 cnm.header.size = htons (sizeof (struct ConnectNotifyMessage));
3074 cnm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_PRE_CONNECT);
3075 cnm.distance = htonl (n->last_distance);
3076 cnm.latency = GNUNET_TIME_relative_hton (n->last_latency);
3078 send_to_all_clients (&cnm.header, GNUNET_YES, GNUNET_CORE_OPTION_SEND_PRE_CONNECT);
3084 * Free the given entry for the neighbour (it has
3085 * already been removed from the list at this point).
3087 * @param n neighbour to free
3090 free_neighbour (struct Neighbour *n)
3092 struct MessageEntry *m;
3094 if (n->pitr != NULL)
3096 GNUNET_PEERINFO_iterate_cancel (n->pitr);
3101 GNUNET_free (n->skm);
3104 while (NULL != (m = n->messages))
3106 n->messages = m->next;
3109 while (NULL != (m = n->encrypted_head))
3111 n->encrypted_head = m->next;
3115 GNUNET_TRANSPORT_notify_transmit_ready_cancel (n->th);
3116 if (n->retry_plaintext_task != GNUNET_SCHEDULER_NO_TASK)
3117 GNUNET_SCHEDULER_cancel (sched, n->retry_plaintext_task);
3118 if (n->retry_set_key_task != GNUNET_SCHEDULER_NO_TASK)
3119 GNUNET_SCHEDULER_cancel (sched, n->retry_set_key_task);
3120 if (n->quota_update_task != GNUNET_SCHEDULER_NO_TASK)
3121 GNUNET_SCHEDULER_cancel (sched, n->quota_update_task);
3122 GNUNET_free_non_null (n->public_key);
3123 GNUNET_free_non_null (n->pending_ping);
3129 * Function called by transport telling us that a peer
3132 * @param cls closure
3133 * @param peer the peer that disconnected
3136 handle_transport_notify_disconnect (void *cls,
3137 const struct GNUNET_PeerIdentity *peer)
3139 struct DisconnectNotifyMessage cnm;
3140 struct Neighbour *n;
3141 struct Neighbour *p;
3144 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3145 "Peer `%4s' disconnected from us.\n", GNUNET_i2s (peer));
3149 while ((n != NULL) &&
3150 (0 != memcmp (&n->peer, peer, sizeof (struct GNUNET_PeerIdentity))))
3161 neighbours = n->next;
3164 GNUNET_assert (neighbour_count > 0);
3166 cnm.header.size = htons (sizeof (struct DisconnectNotifyMessage));
3167 cnm.header.type = htons (GNUNET_MESSAGE_TYPE_CORE_NOTIFY_DISCONNECT);
3169 send_to_all_clients (&cnm.header, GNUNET_YES, GNUNET_CORE_OPTION_SEND_DISCONNECT);
3175 * Last task run during shutdown. Disconnects us from
3179 cleaning_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
3181 struct Neighbour *n;
3185 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3186 "Core service shutting down.\n");
3188 GNUNET_assert (transport != NULL);
3189 GNUNET_TRANSPORT_disconnect (transport);
3191 while (NULL != (n = neighbours))
3193 neighbours = n->next;
3194 GNUNET_assert (neighbour_count > 0);
3198 GNUNET_SERVER_notification_context_destroy (notifier);
3200 while (NULL != (c = clients))
3201 handle_client_disconnect (NULL, c->client_handle);
3202 if (my_private_key != NULL)
3203 GNUNET_CRYPTO_rsa_key_free (my_private_key);
3208 * Initiate core service.
3210 * @param cls closure
3211 * @param s scheduler to use
3212 * @param serv the initialized server
3213 * @param c configuration to use
3217 struct GNUNET_SCHEDULER_Handle *s,
3218 struct GNUNET_SERVER_Handle *serv,
3219 const struct GNUNET_CONFIGURATION_Handle *c)
3222 unsigned long long qin;
3223 unsigned long long qout;
3224 unsigned long long tneigh;
3230 /* parse configuration */
3233 GNUNET_CONFIGURATION_get_value_number (c,
3236 &bandwidth_target_in)) ||
3238 GNUNET_CONFIGURATION_get_value_number (c,
3241 &bandwidth_target_out)) ||
3243 GNUNET_CONFIGURATION_get_value_filename (c,
3245 "HOSTKEY", &keyfile)))
3247 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3249 ("Core service is lacking key configuration settings. Exiting.\n"));
3250 GNUNET_SCHEDULER_shutdown (s);
3253 my_private_key = GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
3254 GNUNET_free (keyfile);
3255 if (my_private_key == NULL)
3257 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3258 _("Core service could not access hostkey. Exiting.\n"));
3259 GNUNET_SCHEDULER_shutdown (s);
3262 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &my_public_key);
3263 GNUNET_CRYPTO_hash (&my_public_key,
3264 sizeof (my_public_key), &my_identity.hashPubKey);
3265 /* setup notification */
3267 notifier = GNUNET_SERVER_notification_context_create (server,
3269 GNUNET_SERVER_disconnect_notify (server, &handle_client_disconnect, NULL);
3270 /* setup transport connection */
3271 transport = GNUNET_TRANSPORT_connect (sched,
3274 &handle_transport_receive,
3275 &handle_transport_notify_connect,
3276 &handle_transport_notify_disconnect);
3277 GNUNET_assert (NULL != transport);
3278 GNUNET_SCHEDULER_add_delayed (sched,
3279 GNUNET_TIME_UNIT_FOREVER_REL,
3280 &cleaning_task, NULL);
3281 /* process client requests */
3282 GNUNET_SERVER_add_handlers (server, handlers);
3283 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3284 _("Core service of `%4s' ready.\n"), GNUNET_i2s (&my_identity));
3290 * The main function for the transport service.
3292 * @param argc number of arguments from the command line
3293 * @param argv command line arguments
3294 * @return 0 ok, 1 on error
3297 main (int argc, char *const *argv)
3299 return (GNUNET_OK ==
3300 GNUNET_SERVICE_run (argc,
3303 GNUNET_SERVICE_OPTION_NONE,
3304 &run, NULL)) ? 0 : 1;
3307 /* end of gnunet-service-core.c */