2 This file is part of GNUnet.
3 (C) 2013 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
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 #include "gnunet_util_lib.h"
24 #include "gnunet_signatures.h"
25 #include "gnunet_statistics_service.h"
27 #include "mesh_protocol_enc.h"
28 #include "mesh_path.h"
30 #include "gnunet-service-mesh_tunnel.h"
31 #include "gnunet-service-mesh_connection.h"
32 #include "gnunet-service-mesh_channel.h"
33 #include "gnunet-service-mesh_peer.h"
35 #define LOG(level, ...) GNUNET_log_from(level,"mesh-tun",__VA_ARGS__)
37 #define REKEY_WAIT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 30)
39 /******************************************************************************/
40 /******************************** STRUCTS **********************************/
41 /******************************************************************************/
45 struct MeshTChannel *next;
46 struct MeshTChannel *prev;
47 struct MeshChannel *ch;
50 struct MeshTConnection
52 struct MeshTConnection *next;
53 struct MeshTConnection *prev;
54 struct MeshConnection *c;
58 * Structure used during a Key eXchange.
60 struct MeshTunnelKXCtx
63 * Decryption ("their") old key, for decrypting traffic sent by the
64 * other end before the key exchange started.
66 struct GNUNET_CRYPTO_SymmetricSessionKey d_key_old;
69 * Challenge to send in a ping and expect in the pong.
75 * Struct containing all information regarding a tunnel to a peer.
80 * Endpoint of the tunnel.
82 struct MeshPeer *peer;
85 * State of the tunnel.
87 enum MeshTunnel3State state;
90 * Key eXchange context.
92 struct MeshTunnelKXCtx *kx_ctx;
95 * Encryption ("our") key.
97 struct GNUNET_CRYPTO_SymmetricSessionKey e_key;
100 * Decryption ("their") key.
102 struct GNUNET_CRYPTO_SymmetricSessionKey d_key;
105 * Task to start the rekey process.
107 GNUNET_SCHEDULER_TaskIdentifier rekey_task;
110 * Paths that are actively used to reach the destination peer.
112 struct MeshTConnection *connection_head;
113 struct MeshTConnection *connection_tail;
116 * Next connection number.
121 * Channels inside this tunnel.
123 struct MeshTChannel *channel_head;
124 struct MeshTChannel *channel_tail;
127 * Channel ID for the next created channel.
129 MESH_ChannelNumber next_chid;
132 * Destroy flag: if true, destroy on last message.
137 * Queued messages, to transmit once tunnel gets connected.
139 struct MeshTunnelQueue *tq_head;
140 struct MeshTunnelQueue *tq_tail;
145 * Struct used to queue messages in a tunnel.
147 struct MeshTunnelQueue
152 struct MeshTunnelQueue *next;
153 struct MeshTunnelQueue *prev;
158 struct MeshChannel *ch;
163 /* struct GNUNET_MessageHeader *msg; */
167 /******************************************************************************/
168 /******************************* GLOBALS ***********************************/
169 /******************************************************************************/
172 * Global handle to the statistics service.
174 extern struct GNUNET_STATISTICS_Handle *stats;
177 * Local peer own ID (memory efficient handle).
179 extern GNUNET_PEER_Id myid;
182 * Local peer own ID (full value).
184 extern struct GNUNET_PeerIdentity my_full_id;
188 * Set of all tunnels, in order to trigger a new exchange on rekey.
189 * Indexed by peer's ID.
191 static struct GNUNET_CONTAINER_MultiPeerMap *tunnels;
194 * Default TTL for payload packets.
196 static unsigned long long default_ttl;
201 const static struct GNUNET_CRYPTO_EddsaPrivateKey *my_private_key;
204 * Own ephemeral private key.
206 static struct GNUNET_CRYPTO_EcdhePrivateKey *my_ephemeral_key;
209 * Cached message used to perform a key exchange.
211 static struct GNUNET_MESH_KX_Ephemeral kx_msg;
214 * Task to generate a new ephemeral key.
216 static GNUNET_SCHEDULER_TaskIdentifier rekey_task;
221 static struct GNUNET_TIME_Relative rekey_period;
223 /******************************************************************************/
224 /******************************** STATIC ***********************************/
225 /******************************************************************************/
228 * Get string description for tunnel state.
230 * @param s Tunnel state.
232 * @return String representation.
235 GMT_state2s (enum MeshTunnel3State s)
237 static char buf[128];
241 case MESH_TUNNEL3_NEW:
242 return "MESH_TUNNEL3_NEW";
243 case MESH_TUNNEL3_SEARCHING:
244 return "MESH_TUNNEL3_SEARCHING";
245 case MESH_TUNNEL3_WAITING:
246 return "MESH_TUNNEL3_WAITING";
247 case MESH_TUNNEL3_KEY_SENT:
248 return "MESH_TUNNEL3_KEY_SENT";
249 case MESH_TUNNEL3_PING_SENT:
250 return "MESH_TUNNEL3_PING_SENT";
251 case MESH_TUNNEL3_READY:
252 return "MESH_TUNNEL3_READY";
253 case MESH_TUNNEL3_RECONNECTING:
254 return "MESH_TUNNEL3_RECONNECTING";
255 case MESH_TUNNEL3_REKEY:
256 return "MESH_TUNNEL3_REKEY";
259 sprintf (buf, "%u (UNKNOWN STATE)", s);
266 * Ephemeral key message purpose size.
268 * @return Size of the part of the ephemeral key message that must be signed.
271 ephemeral_purpose_size (void)
273 return sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
274 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
275 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
276 sizeof (struct GNUNET_CRYPTO_EcdhePublicKey) +
277 sizeof (struct GNUNET_PeerIdentity);
282 * Size of the encrypted part of a ping message.
284 * @return Size of the encrypted part of a ping message.
287 ping_encryption_size (void)
289 return sizeof (struct GNUNET_PeerIdentity) + sizeof (uint32_t);
294 * Get the channel's buffer. ONLY FOR NON-LOOPBACK CHANNELS!!
296 * @param tch Tunnel's channel handle.
298 * @return Amount of messages the channel can still buffer towards the client.
301 get_channel_buffer (const struct MeshTChannel *tch)
305 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
306 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
308 return GMCH_get_buffer (tch->ch, fwd);
313 * Get the channel's allowance status.
315 * @param tch Tunnel's channel handle.
317 * @return #GNUNET_YES if we allowed the client to send data to us.
320 get_channel_allowed (const struct MeshTChannel *tch)
324 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
325 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
327 return GMCH_get_allowed (tch->ch, fwd);
332 * Get the connection's buffer.
334 * @param tc Tunnel's connection handle.
336 * @return Amount of messages the connection can still buffer.
339 get_connection_buffer (const struct MeshTConnection *tc)
343 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
344 fwd = GMC_is_origin (tc->c, GNUNET_YES);
346 return GMC_get_buffer (tc->c, fwd);
351 * Get the connection's allowance.
353 * @param tc Tunnel's connection handle.
355 * @return Amount of messages we have allowed the next peer to send us.
358 get_connection_allowed (const struct MeshTConnection *tc)
362 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
363 fwd = GMC_is_origin (tc->c, GNUNET_YES);
365 return GMC_get_allowed (tc->c, fwd);
370 * Check that a ephemeral key message s well formed and correctly signed.
372 * @param t Tunnel on which the message came.
373 * @param msg The ephemeral key message.
375 * @return GNUNET_OK if message is fine, GNUNET_SYSERR otherwise.
378 check_ephemeral (struct MeshTunnel3 *t,
379 const struct GNUNET_MESH_KX_Ephemeral *msg)
381 /* Check message size */
382 if (ntohs (msg->header.size) != sizeof (struct GNUNET_MESH_KX_Ephemeral))
383 return GNUNET_SYSERR;
385 /* Check signature size */
386 if (ntohl (msg->purpose.size) != ephemeral_purpose_size ())
387 return GNUNET_SYSERR;
390 if (0 != memcmp (&msg->origin_identity,
391 GMP_get_id (t->peer),
392 sizeof (struct GNUNET_PeerIdentity)))
393 return GNUNET_SYSERR;
395 /* Check signature */
397 GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_MESH_KX,
400 &msg->origin_identity.public_key))
401 return GNUNET_SYSERR;
408 * Encrypt data with the tunnel key.
410 * @param t Tunnel whose key to use.
411 * @param dst Destination for the encrypted data.
412 * @param src Source of the plaintext. Can overlap with @c dst.
413 * @param size Size of the plaintext.
414 * @param iv Initialization Vector to use.
417 t_encrypt (struct MeshTunnel3 *t,
418 void *dst, const void *src,
419 size_t size, uint32_t iv)
421 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
423 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->e_key, &iv, sizeof (uint32_t), NULL);
424 return GNUNET_CRYPTO_symmetric_encrypt (src, size, &t->e_key, &siv, dst);
429 * Decrypt data with the tunnel key.
431 * @param t Tunnel whose key to use.
432 * @param dst Destination for the plaintext.
433 * @param src Source of the encrypted data. Can overlap with @c dst.
434 * @param size Size of the encrypted data.
435 * @param iv Initialization Vector to use.
438 t_decrypt (struct MeshTunnel3 *t,
439 void *dst, const void *src,
440 size_t size, uint32_t iv)
442 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
444 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->e_key, &iv, sizeof (uint32_t), NULL);
445 return GNUNET_CRYPTO_symmetric_decrypt (src, size, &t->d_key, &siv, dst);
450 * Create key material by doing ECDH on the local and remote ephemeral keys.
452 * @param key_material Where to store the key material.
453 * @param ephemeral_key Peer's public ephemeral key.
456 derive_key_material (struct GNUNET_HashCode *key_material,
457 const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key)
460 GNUNET_CRYPTO_ecc_ecdh (my_ephemeral_key,
469 * Create a symmetic key from the identities of both ends and the key material
472 * @param key Destination for the generated key.
473 * @param sender ID of the peer that will encrypt with @c key.
474 * @param receiver ID of the peer that will decrypt with @c key.
475 * @param key_material Hash created with ECDH with the ephemeral keys.
478 derive_symmertic (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
479 const struct GNUNET_PeerIdentity *sender,
480 const struct GNUNET_PeerIdentity *receiver,
481 const struct GNUNET_HashCode *key_material)
483 const char salt[] = "MESH kx salt";
485 GNUNET_CRYPTO_kdf (key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
487 key_material, sizeof (struct GNUNET_HashCode),
488 sender, sizeof (struct GNUNET_PeerIdentity),
489 receiver, sizeof (struct GNUNET_PeerIdentity),
494 * Pick a connection on which send the next data message.
496 * @param t Tunnel on which to send the message.
498 * @return The connection on which to send the next message.
500 static struct MeshConnection *
501 tunnel_get_connection (struct MeshTunnel3 *t)
503 struct MeshTConnection *iter;
504 struct MeshConnection *best;
506 unsigned int lowest_q;
508 LOG (GNUNET_ERROR_TYPE_DEBUG, "tunnel_get_connection %s\n", GMP_2s (t->peer));
511 for (iter = t->connection_head; NULL != iter; iter = iter->next)
513 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s: %u\n",
514 GNUNET_h2s (GMC_get_id (iter->c)), GMC_get_state (iter->c));
515 if (MESH_CONNECTION_READY == GMC_get_state (iter->c))
517 qn = GMC_get_qn (iter->c, GMC_is_origin (iter->c, GNUNET_YES));
518 LOG (GNUNET_ERROR_TYPE_DEBUG, " q_n %u, \n", qn);
531 * Send all cached messages that we can, tunnel is online.
533 * @param t Tunnel that holds the messages. Cannot be loopback.
536 send_queued_data (struct MeshTunnel3 *t)
538 struct MeshTunnelQueue *tq;
539 struct MeshTunnelQueue *next;
542 LOG (GNUNET_ERROR_TYPE_DEBUG,
543 "GMT_send_queued_data on tunnel %s\n",
546 if (GMT_is_loopback (t))
552 room = GMT_get_connections_buffer (t);
553 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
554 for (tq = t->tq_head; NULL != tq && room > 0; tq = next)
556 LOG (GNUNET_ERROR_TYPE_DEBUG, " data on channel %s\n", GMCH_2s (tq->ch));
559 GNUNET_CONTAINER_DLL_remove (t->tq_head, t->tq_tail, tq);
560 GMCH_send_prebuilt_message ((struct GNUNET_MessageHeader *) &tq[1],
561 tq->ch, GMCH_is_origin (tq->ch, GNUNET_YES));
565 LOG (GNUNET_ERROR_TYPE_DEBUG,
566 "GMT_send_queued_data end\n",
574 * Cache a message to be sent once tunnel is online.
576 * @param t Tunnel to hold the message.
577 * @param ch Channel the message is about.
578 * @param msg Message itself (copy will be made).
581 queue_data (struct MeshTunnel3 *t,
582 struct MeshChannel *ch,
583 const struct GNUNET_MessageHeader *msg)
585 struct MeshTunnelQueue *tq;
586 uint16_t size = ntohs (msg->size);
588 if (MESH_TUNNEL3_READY == t->state)
594 tq = GNUNET_malloc (sizeof (struct MeshTunnelQueue) + size);
597 memcpy (&tq[1], msg, size);
598 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tq);
604 * Sends key exchange message on a tunnel, choosing the best connection.
605 * Should not be called on loopback tunnels.
607 * @param t Tunnel on which this message is transmitted.
608 * @param message Message to send. Function modifies it.
611 send_kx (struct MeshTunnel3 *t,
612 const struct GNUNET_MessageHeader *message)
614 struct MeshConnection *c;
615 struct GNUNET_MESH_KX *msg;
616 size_t size = ntohs (message->size);
617 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
621 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
623 /* Avoid loopback. */
624 if (GMT_is_loopback (t))
626 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
631 /* Must have a connection. */
632 if (NULL == t->connection_head)
638 msg = (struct GNUNET_MESH_KX *) cbuf;
639 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
640 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
641 c = tunnel_get_connection (t);
644 GNUNET_break (GNUNET_YES == t->destroy);
647 type = ntohs (message->type);
650 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
651 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
652 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
653 msg->cid = *GMC_get_id (c);
654 msg->reserved = htonl (0);
655 memcpy (&msg[1], message, size);
658 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
659 GNUNET_MESH_DEBUG_M2S (type));
663 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
664 GMC_send_prebuilt_message (&msg->header, c, fwd);
669 * Send the ephemeral key on a tunnel.
671 * @param t Tunnel on which to send the key.
674 send_ephemeral (struct MeshTunnel3 *t)
676 kx_msg.sender_status = htonl (t->state);
678 send_kx (t, &kx_msg.header);
682 * Send a ping message on a tunnel.
684 * @param t Tunnel on which to send the ping.
687 send_ping (struct MeshTunnel3 *t)
689 struct GNUNET_MESH_KX_Ping msg;
691 msg.header.size = htons (sizeof (msg));
692 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
693 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
694 msg.target = *GMP_get_id (t->peer);
695 msg.nonce = t->kx_ctx->challenge;
696 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
698 send_kx (t, &msg.header);
703 * Send a pong message on a tunnel.
705 * @param t Tunnel on which to send the pong.
706 * @param challenge Value sent in the ping that we have to send back.
709 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
711 struct GNUNET_MESH_KX_Pong msg;
713 msg.header.size = htons (sizeof (msg));
714 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
715 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
716 msg.nonce = challenge;
717 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
719 send_kx (t, &msg.header);
724 * Initiate a rekey with the remote peer.
726 * @param cls Closure (tunnel).
727 * @param tc TaskContext.
730 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
732 struct MeshTunnel3 *t = cls;
734 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
736 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
739 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
740 t->kx_ctx->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
742 t->kx_ctx->d_key_old = t->d_key;
744 if (MESH_TUNNEL3_READY == t->state)
747 t->state = MESH_TUNNEL3_REKEY;
749 else if (MESH_TUNNEL3_WAITING == t->state)
751 t->state = MESH_TUNNEL3_KEY_SENT;
755 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->state);
758 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
763 * Out ephemeral key has changed, create new session key on all tunnels.
765 * @param cls Closure (size of the hashmap).
766 * @param key Current public key.
767 * @param value Value in the hash map (tunnel).
769 * @return #GNUNET_YES, so we should continue to iterate,
772 rekey_iterator (void *cls,
773 const struct GNUNET_PeerIdentity *key,
776 struct MeshTunnel3 *t = value;
777 struct GNUNET_TIME_Relative delay;
781 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
784 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
785 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
786 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
793 * Create a new ephemeral key and key message, schedule next rekeying.
795 * @param cls Closure (unused).
796 * @param tc TaskContext.
799 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
801 struct GNUNET_TIME_Absolute time;
804 rekey_task = GNUNET_SCHEDULER_NO_TASK;
806 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
809 GNUNET_free_non_null (my_ephemeral_key);
810 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
812 time = GNUNET_TIME_absolute_get ();
813 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
814 time = GNUNET_TIME_absolute_add (time, rekey_period);
815 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
816 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
817 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
819 GNUNET_assert (GNUNET_OK ==
820 GNUNET_CRYPTO_eddsa_sign (my_private_key,
824 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
825 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
827 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
832 * Demultiplex data per channel and call appropriate channel handler.
834 * @param t Tunnel on which the data came.
835 * @param msg Data message.
836 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
837 * #GNUNET_YES if message is FWD on the respective channel (loopback)
838 * #GNUNET_NO if message is BCK on the respective channel (loopback)
839 * #GNUNET_SYSERR if message on a one-ended channel (remote)
842 handle_data (struct MeshTunnel3 *t,
843 const struct GNUNET_MESH_Data *msg,
846 struct MeshChannel *ch;
851 size = ntohs (msg->header.size);
853 sizeof (struct GNUNET_MESH_Data) +
854 sizeof (struct GNUNET_MessageHeader))
859 type = ntohs (msg->header.type);
860 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message\n",
861 GNUNET_MESH_DEBUG_M2S (type));
862 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
863 GNUNET_MESH_DEBUG_M2S (ntohs (msg[1].header.type)));
866 ch = GMT_get_channel (t, ntohl (msg->chid));
869 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
871 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
876 GMT_change_state (t, MESH_TUNNEL3_READY);
877 GMCH_handle_data (ch, msg, fwd);
882 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
884 * @param t Tunnel on which the DATA ACK came.
885 * @param msg DATA ACK message.
886 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
887 * #GNUNET_YES if message is FWD on the respective channel (loopback)
888 * #GNUNET_NO if message is BCK on the respective channel (loopback)
889 * #GNUNET_SYSERR if message on a one-ended channel (remote)
892 handle_data_ack (struct MeshTunnel3 *t,
893 const struct GNUNET_MESH_DataACK *msg,
896 struct MeshChannel *ch;
900 size = ntohs (msg->header.size);
901 if (size != sizeof (struct GNUNET_MESH_DataACK))
908 ch = GMT_get_channel (t, ntohl (msg->chid));
911 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
913 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
918 GMCH_handle_data_ack (ch, msg, fwd);
923 * Handle channel create.
925 * @param t Tunnel on which the data came.
926 * @param msg Data message.
929 handle_ch_create (struct MeshTunnel3 *t,
930 const struct GNUNET_MESH_ChannelCreate *msg)
932 struct MeshChannel *ch;
936 size = ntohs (msg->header.size);
937 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
944 ch = GMT_get_channel (t, ntohl (msg->chid));
945 if (NULL != ch && ! GMT_is_loopback (t))
947 /* Probably a retransmission, safe to ignore */
948 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
952 ch = GMCH_handle_create (t, msg);
954 GMT_add_channel (t, ch);
960 * Handle channel NACK.
962 * @param t Tunnel on which the data came.
963 * @param msg Data message.
966 handle_ch_nack (struct MeshTunnel3 *t,
967 const struct GNUNET_MESH_ChannelManage *msg)
969 struct MeshChannel *ch;
973 size = ntohs (msg->header.size);
974 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
981 ch = GMT_get_channel (t, ntohl (msg->chid));
982 if (NULL != ch && ! GMT_is_loopback (t))
984 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
986 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
991 GMCH_handle_nack (ch);
996 * Handle a CHANNEL ACK (SYNACK/ACK).
998 * @param t Tunnel on which the CHANNEL ACK came.
999 * @param msg CHANNEL ACK message.
1000 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1001 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1002 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1003 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1006 handle_ch_ack (struct MeshTunnel3 *t,
1007 const struct GNUNET_MESH_ChannelManage *msg,
1010 struct MeshChannel *ch;
1014 size = ntohs (msg->header.size);
1015 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1022 ch = GMT_get_channel (t, ntohl (msg->chid));
1025 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1027 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1032 GMCH_handle_ack (ch, msg, fwd);
1038 * Handle a channel destruction message.
1040 * @param t Tunnel on which the message came.
1041 * @param msg Channel destroy message.
1042 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1043 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1044 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1045 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1048 handle_ch_destroy (struct MeshTunnel3 *t,
1049 const struct GNUNET_MESH_ChannelManage *msg,
1052 struct MeshChannel *ch;
1056 size = ntohs (msg->header.size);
1057 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1064 ch = GMT_get_channel (t, ntohl (msg->chid));
1067 /* Probably a retransmission, safe to ignore */
1071 GMCH_handle_destroy (ch, msg, fwd);
1076 * The peer's ephemeral key has changed: update the symmetrical keys.
1078 * @param t Tunnel this message came on.
1079 * @param msg Key eXchange message.
1082 handle_ephemeral (struct MeshTunnel3 *t,
1083 const struct GNUNET_MESH_KX_Ephemeral *msg)
1085 struct GNUNET_HashCode km;
1086 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1088 if (GNUNET_OK != check_ephemeral (t, msg))
1090 GNUNET_break_op (0);
1093 derive_key_material (&km, &msg->ephemeral_key);
1094 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1095 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1096 if (MESH_TUNNEL3_KEY_SENT == t->state)
1099 t->state = MESH_TUNNEL3_PING_SENT;
1105 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1106 * Answer with by retransmitting the challenge with the "opposite" key.
1108 * @param t Tunnel this message came on.
1109 * @param msg Key eXchange Ping message.
1112 handle_ping (struct MeshTunnel3 *t,
1113 const struct GNUNET_MESH_KX_Ping *msg)
1115 struct GNUNET_MESH_KX_Ping res;
1117 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1118 t_decrypt (t, &res.target, &msg->target, ping_encryption_size(), msg->iv);
1119 if (0 != memcmp (&my_full_id, &msg->target, sizeof (my_full_id)))
1122 LOG (GNUNET_ERROR_TYPE_DEBUG, " at %s\n", GNUNET_i2s (&my_full_id));
1123 LOG (GNUNET_ERROR_TYPE_DEBUG, " for %s\n", GNUNET_i2s (&msg->target));
1127 send_pong (t, res.iv);
1132 * Peer has answer to our challenge.
1133 * If answer is successful, consider the key exchange finished and clean
1134 * up all related state.
1136 * @param t Tunnel this message came on.
1137 * @param msg Key eXchange Pong message.
1140 handle_pong (struct MeshTunnel3 *t,
1141 const struct GNUNET_MESH_KX_Pong *msg)
1145 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1146 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1148 GNUNET_break_op (0);
1151 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1153 if (challenge != t->kx_ctx->challenge)
1155 LOG (GNUNET_ERROR_TYPE_DEBUG,
1156 "Wrong PONG challenge: %u. Expected: %u.\n",
1157 challenge, t->kx_ctx->challenge);
1158 GNUNET_break_op (0);
1161 GNUNET_SCHEDULER_cancel (t->rekey_task);
1162 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1163 GNUNET_free (t->kx_ctx);
1165 t->state = MESH_TUNNEL3_READY;
1166 send_queued_data (t);
1171 * Demultiplex by message type and call appropriate handler for a message
1172 * towards a channel of a local tunnel.
1174 * @param t Tunnel this message came on.
1175 * @param msgh Message header.
1176 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1177 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1178 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1179 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1182 handle_decrypted (struct MeshTunnel3 *t,
1183 const struct GNUNET_MessageHeader *msgh,
1188 type = ntohs (msgh->type);
1189 LOG (GNUNET_ERROR_TYPE_DEBUG,
1190 "Got a %s message!\n",
1191 GNUNET_MESH_DEBUG_M2S (type));
1195 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1196 /* Don't send hop ACK, wait for client to ACK */
1197 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1200 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1201 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1204 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1205 handle_ch_create (t,
1206 (struct GNUNET_MESH_ChannelCreate *) msgh);
1209 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1211 (struct GNUNET_MESH_ChannelManage *) msgh);
1214 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1216 (struct GNUNET_MESH_ChannelManage *) msgh,
1220 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1221 handle_ch_destroy (t,
1222 (struct GNUNET_MESH_ChannelManage *) msgh,
1227 GNUNET_break_op (0);
1228 LOG (GNUNET_ERROR_TYPE_DEBUG,
1229 "end-to-end message not known (%u)\n",
1230 ntohs (msgh->type));
1234 /******************************************************************************/
1235 /******************************** API ***********************************/
1236 /******************************************************************************/
1239 * Decrypt and demultiplex by message type. Call appropriate handler
1240 * for every message.
1242 * @param t Tunnel this message came on.
1243 * @param msg Encrypted message.
1246 GMT_handle_encrypted (struct MeshTunnel3 *t,
1247 const struct GNUNET_MESH_Encrypted *msg)
1249 size_t size = ntohs (msg->header.size);
1250 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1251 size_t decrypted_size;
1252 char cbuf [payload_size];
1253 struct GNUNET_MessageHeader *msgh;
1256 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1258 while (off < decrypted_size)
1260 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1261 handle_decrypted (t, msgh, GNUNET_SYSERR);
1262 off += ntohs (msgh->size);
1268 * Demultiplex an encapsulated KX message by message type.
1270 * @param t Tunnel on which the message came.
1271 * @param message Payload of KX message.
1274 GMT_handle_kx (struct MeshTunnel3 *t,
1275 const struct GNUNET_MessageHeader *message)
1279 type = ntohs (message->type);
1280 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1283 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1284 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1287 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1288 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1291 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1292 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1296 GNUNET_break_op (0);
1297 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1303 * Initialize the tunnel subsystem.
1305 * @param c Configuration handle.
1306 * @param key ECC private key, to derive all other keys and do crypto.
1309 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1310 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1312 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1314 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1317 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1318 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1322 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1325 rekey_period = GNUNET_TIME_UNIT_DAYS;
1328 my_private_key = key;
1329 kx_msg.header.size = htons (sizeof (kx_msg));
1330 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1331 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1332 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1333 kx_msg.origin_identity = my_full_id;
1334 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1336 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1341 * Shut down the tunnel subsystem.
1346 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1348 GNUNET_SCHEDULER_cancel (rekey_task);
1349 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1351 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1358 * @param destination Peer this tunnel is towards.
1360 struct MeshTunnel3 *
1361 GMT_new (struct MeshPeer *destination)
1363 struct MeshTunnel3 *t;
1365 t = GNUNET_new (struct MeshTunnel3);
1367 t->peer = destination;
1370 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1371 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1382 * Change the tunnel state.
1384 * @param t Tunnel whose state to change.
1385 * @param state New state.
1388 GMT_change_state (struct MeshTunnel3* t, enum MeshTunnel3State state)
1392 LOG (GNUNET_ERROR_TYPE_DEBUG,
1393 "Tunnel %s state was %s\n",
1395 GMT_state2s (t->state));
1396 LOG (GNUNET_ERROR_TYPE_DEBUG,
1397 "Tunnel %s state is now %s\n",
1399 GMT_state2s (state));
1400 if (myid != GMP_get_short_id (t->peer) &&
1401 MESH_TUNNEL3_WAITING == t->state && MESH_TUNNEL3_READY == state)
1403 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1404 rekey_tunnel (t, NULL);
1405 LOG (GNUNET_ERROR_TYPE_DEBUG,
1406 "Tunnel %s state is now %s\n",
1408 GMT_state2s (t->state));
1414 if (MESH_TUNNEL3_READY == state && 3 <= GMT_count_connections (t))
1416 GMP_stop_search (t->peer);
1422 * Add a connection to a tunnel.
1425 * @param c Connection.
1428 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1430 struct MeshTConnection *aux;
1432 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1436 aux = GNUNET_new (struct MeshTConnection);
1438 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1443 * Remove a connection from a tunnel.
1446 * @param c Connection.
1449 GMT_remove_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1451 struct MeshTConnection *aux;
1453 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1456 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1464 * Add a channel to a tunnel.
1467 * @param ch Channel.
1470 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1472 struct MeshTChannel *aux;
1474 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1476 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1478 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1483 aux = GNUNET_new (struct MeshTChannel);
1485 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1486 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1491 * Remove a channel from a tunnel.
1494 * @param ch Channel.
1497 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1499 struct MeshTChannel *aux;
1501 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1502 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1506 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1507 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1516 * Search for a channel by global ID.
1518 * @param t Tunnel containing the channel.
1519 * @param chid Public channel number.
1521 * @return channel handler, NULL if doesn't exist
1523 struct MeshChannel *
1524 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1526 struct MeshTChannel *iter;
1531 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1533 if (GMCH_get_id (iter->ch) == chid)
1537 return NULL == iter ? NULL : iter->ch;
1542 * Tunnel is empty: destroy it.
1544 * Notifies all connections about the destruction.
1546 * @param t Tunnel to destroy.
1549 GMT_destroy_empty (struct MeshTunnel3 *t)
1551 struct MeshTConnection *iter;
1553 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1555 GMC_send_destroy (iter->c);
1558 t->destroy = GNUNET_YES;
1563 * Destroy tunnel if empty (no more channels).
1565 * @param t Tunnel to destroy if empty.
1568 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1570 if (1 < GMT_count_channels (t))
1573 GMT_destroy_empty (t);
1578 * Destroy the tunnel.
1580 * This function does not generate any warning traffic to clients or peers.
1583 * Cancel messages belonging to this tunnel queued to neighbors.
1584 * Free any allocated resources linked to the tunnel.
1586 * @param t The tunnel to destroy.
1589 GMT_destroy (struct MeshTunnel3 *t)
1591 struct MeshTConnection *iter;
1592 struct MeshTConnection *next;
1597 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
1599 // if (GNUNET_YES != GNUNET_CONTAINER_multihashmap_remove (tunnels, &t->id, t))
1600 // GNUNET_break (0);
1602 for (iter = t->connection_head; NULL != iter; iter = next)
1605 GMC_destroy (iter->c);
1608 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
1609 GMP_set_tunnel (t->peer, NULL);
1611 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1612 GNUNET_SCHEDULER_cancel (t->rekey_task);
1619 * @brief Use the given path for the tunnel.
1620 * Update the next and prev hops (and RCs).
1621 * (Re)start the path refresh in case the tunnel is locally owned.
1623 * @param t Tunnel to update.
1624 * @param p Path to use.
1626 * @return Connection created.
1628 struct MeshConnection *
1629 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
1631 struct MeshConnection *c;
1632 struct GNUNET_HashCode cid;
1633 unsigned int own_pos;
1635 if (NULL == t || NULL == p)
1641 for (own_pos = 0; own_pos < p->length; own_pos++)
1643 if (p->peers[own_pos] == myid)
1646 if (own_pos > p->length - 1)
1652 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
1653 c = GMC_new (&cid, t, p, own_pos);
1654 GMT_add_connection (t, c);
1660 * Count established (ready) connections of a tunnel.
1662 * @param t Tunnel on which to count.
1664 * @return Number of connections.
1667 GMT_count_connections (struct MeshTunnel3 *t)
1669 struct MeshTConnection *iter;
1672 for (count = 0, iter = t->connection_head;
1674 iter = iter->next, count++);
1680 * Count channels of a tunnel.
1682 * @param t Tunnel on which to count.
1684 * @return Number of channels.
1687 GMT_count_channels (struct MeshTunnel3 *t)
1689 struct MeshTChannel *iter;
1692 for (count = 0, iter = t->channel_head;
1694 iter = iter->next, count++) /* skip */;
1701 * Get the state of a tunnel.
1705 * @return Tunnel's state.
1707 enum MeshTunnel3State
1708 GMT_get_state (struct MeshTunnel3 *t)
1713 return (enum MeshTunnel3State) -1;
1720 * Get the maximum buffer space for a tunnel towards a local client.
1724 * @return Biggest buffer space offered by any channel in the tunnel.
1727 GMT_get_channels_buffer (struct MeshTunnel3 *t)
1729 struct MeshTChannel *iter;
1730 unsigned int buffer;
1731 unsigned int ch_buf;
1733 if (NULL == t->channel_head)
1735 /* Probably getting buffer for a channel create/handshake. */
1740 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1742 ch_buf = get_channel_buffer (iter);
1743 if (ch_buf > buffer)
1751 * Get the total buffer space for a tunnel for P2P traffic.
1755 * @return Buffer space offered by all connections in the tunnel.
1758 GMT_get_connections_buffer (struct MeshTunnel3 *t)
1760 struct MeshTConnection *iter;
1761 unsigned int buffer;
1763 iter = t->connection_head;
1765 while (NULL != iter)
1767 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
1773 buffer += get_connection_buffer (iter);
1782 * Get the tunnel's destination.
1786 * @return ID of the destination peer.
1788 const struct GNUNET_PeerIdentity *
1789 GMT_get_destination (struct MeshTunnel3 *t)
1791 return GMP_get_id (t->peer);
1796 * Get the tunnel's next free global channel ID.
1800 * @return GID of a channel free to use.
1803 GMT_get_next_chid (struct MeshTunnel3 *t)
1805 MESH_ChannelNumber chid;
1807 while (NULL != GMT_get_channel (t, t->next_chid))
1809 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
1810 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
1812 chid = t->next_chid;
1813 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
1820 * Send ACK on one or more channels due to buffer in connections.
1822 * @param t Channel which has some free buffer space.
1825 GMT_unchoke_channels (struct MeshTunnel3 *t)
1827 struct MeshTChannel *iter;
1828 unsigned int buffer;
1829 unsigned int channels = GMT_count_channels (t);
1830 unsigned int choked_n;
1831 struct MeshChannel *choked[channels];
1833 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
1834 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
1835 if (NULL != t->channel_head)
1836 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
1844 /* Get buffer space */
1845 buffer = GMT_get_connections_buffer (t);
1851 /* Count and remember choked channels */
1853 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1855 if (GNUNET_NO == get_channel_allowed (iter))
1857 choked[choked_n++] = iter->ch;
1861 /* Unchoke random channels */
1862 while (0 < buffer && 0 < choked_n)
1864 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1866 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
1869 choked[r] = choked[choked_n];
1875 * Send ACK on one or more connections due to buffer space to the client.
1877 * Iterates all connections of the tunnel and sends ACKs appropriately.
1882 GMT_send_connection_acks (struct MeshTunnel3 *t)
1884 struct MeshTConnection *iter;
1887 uint32_t allow_per_connection;
1889 unsigned int buffer;
1891 LOG (GNUNET_ERROR_TYPE_DEBUG,
1892 "Tunnel send connection ACKs on %s\n",
1901 buffer = GMT_get_channels_buffer (t);
1903 /* Count connections, how many messages are already allowed */
1904 cs = GMT_count_connections (t);
1905 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
1907 allowed += get_connection_allowed (iter);
1910 /* Make sure there is no overflow */
1911 if (allowed > buffer)
1916 /* Authorize connections to send more data */
1917 to_allow = buffer; /* - allowed; */
1919 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
1921 allow_per_connection = to_allow/cs;
1922 to_allow -= allow_per_connection;
1924 if (get_connection_allowed (iter) > 64 / 3)
1928 GMC_allow (iter->c, buffer, GMC_is_origin (iter->c, GNUNET_YES));
1931 GNUNET_break (to_allow == 0);
1936 * Sends an already built message on a tunnel, encrypting it and
1937 * choosing the best connection.
1939 * @param message Message to send. Function modifies it.
1940 * @param t Tunnel on which this message is transmitted.
1941 * @param ch Channel on which this message is transmitted.
1942 * @param fwd Is this a fwd message on @c ch?
1945 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
1946 struct MeshTunnel3 *t,
1947 struct MeshChannel *ch,
1950 struct MeshConnection *c;
1951 struct GNUNET_MESH_Encrypted *msg;
1952 size_t size = ntohs (message->size);
1953 size_t encrypted_size;
1954 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
1958 if (MESH_TUNNEL3_READY != t->state)
1960 queue_data (t, ch, message);
1963 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
1965 if (GMT_is_loopback (t))
1967 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
1968 handle_decrypted (t, message, fwd);
1972 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
1973 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
1974 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
1976 encrypted_size = t_encrypt (t, &msg[1], message, size, iv);
1977 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + encrypted_size);
1978 c = tunnel_get_connection (t);
1981 GNUNET_break (GNUNET_YES == t->destroy);
1984 type = ntohs (message->type);
1987 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1988 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1989 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1990 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1991 msg->cid = *GMC_get_id (c);
1992 msg->ttl = htonl (default_ttl);
1995 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
1996 GNUNET_MESH_DEBUG_M2S (type));
2000 fwd = GMC_is_origin (c, GNUNET_YES);
2001 GMC_send_prebuilt_message (&msg->header, c, fwd);
2005 * Is the tunnel directed towards the local peer?
2009 * @return #GNUNET_YES if it is loopback.
2012 GMT_is_loopback (const struct MeshTunnel3 *t)
2014 return (myid == GMP_get_short_id (t->peer));
2019 * Is the tunnel using this path already?
2024 * @return #GNUNET_YES a connection uses this path.
2027 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2029 struct MeshTConnection *iter;
2031 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2032 if (GMC_get_path (iter->c) == p)
2040 * Get a cost of a path for a tunnel considering existing connections.
2043 * @param path Candidate path.
2045 * @return Cost of the path (path length + number of overlapping nodes)
2048 GMT_get_path_cost (const struct MeshTunnel3 *t,
2049 const struct MeshPeerPath *path)
2051 struct MeshTConnection *iter;
2052 unsigned int overlap;
2060 GNUNET_assert (NULL != t);
2062 for (i = 0; i < path->length; i++)
2064 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2066 for (j = 0; j < GMC_get_path (iter->c)->length; j++)
2068 if (path->peers[i] == GMC_get_path (iter->c)->peers[j])
2076 return (path->length + overlap) * (path->score * -1);
2081 * Get the static string for the peer this tunnel is directed.
2085 * @return Static string the destination peer's ID.
2088 GMT_2s (const struct MeshTunnel3 *t)
2093 return GMP_2s (t->peer);