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 "mesh_protocol_enc.h"
26 #include "gnunet-service-mesh_tunnel.h"
27 #include "gnunet-service-mesh_connection.h"
28 #include "gnunet-service-mesh_channel.h"
29 #include "gnunet-service-mesh_peer.h"
30 #include "mesh_path.h"
32 #define LOG(level, ...) GNUNET_log_from(level,"mesh-tun",__VA_ARGS__)
35 * All the states a tunnel can be in.
40 * Uninitialized status, should never appear in operation.
45 * Path to the peer not known yet
47 MESH_TUNNEL_SEARCHING,
50 * Request sent, not yet answered.
55 * Peer connected and ready to accept data
60 * Peer connected previosly but not responding
62 MESH_TUNNEL_RECONNECTING
67 /******************************************************************************/
68 /******************************** STRUCTS **********************************/
69 /******************************************************************************/
72 * Struct containing all information regarding a tunnel to a peer.
77 * Endpoint of the tunnel.
79 struct MeshPeer *peer;
82 * State of the tunnel.
84 enum MeshTunnelState state;
87 * Local peer ephemeral private key
89 struct GNUNET_CRYPTO_EccPrivateKey *my_eph_key;
92 * Local peer ephemeral public key
94 struct GNUNET_CRYPTO_EccPublicSignKey *my_eph;
97 * Remote peer's public key.
99 struct GNUNET_CRYPTO_EccPublicSignKey *peers_eph;
102 * Encryption ("our") key.
104 struct GNUNET_CRYPTO_SymmetricSessionKey e_key;
107 * Decryption ("their") key.
109 struct GNUNET_CRYPTO_SymmetricSessionKey d_key;
112 * Paths that are actively used to reach the destination peer.
114 struct MeshConnection *connection_head;
115 struct MeshConnection *connection_tail;
118 * Next connection number.
123 * Channels inside this tunnel.
125 struct MeshChannel *channel_head;
126 struct MeshChannel *channel_tail;
129 * Channel ID for the next created channel.
131 MESH_ChannelNumber next_chid;
134 * Channel ID for the next incoming channel.
136 MESH_ChannelNumber next_local_chid;
139 * Pending message count.
141 int pending_messages;
144 * Destroy flag: if true, destroy on last message.
149 * Queued messages, to transmit once tunnel gets connected.
151 struct MeshTunnelQueue *tq_head;
152 struct MeshTunnelQueue *tq_tail;
157 * Struct used to queue messages in a tunnel.
159 struct MeshTunnelQueue
164 struct MeshTunnelQueue *next;
165 struct MeshTunnelQueue *prev;
170 struct MeshChannel *ch;
175 /* struct GNUNET_MessageHeader *msg; */
178 /******************************************************************************/
179 /******************************* GLOBALS ***********************************/
180 /******************************************************************************/
183 * Default TTL for payload packets.
185 static unsigned long long default_ttl;
188 * Local peer own ID (memory efficient handle).
190 static GNUNET_PEER_Id my_short_id;
193 * Local peer own ID (full value).
195 const static struct GNUNET_PeerIdentity *my_full_id;
200 const static struct GNUNET_CRYPTO_EccPrivateKey *my_private_key;
203 /******************************************************************************/
204 /******************************** STATIC ***********************************/
205 /******************************************************************************/
209 * Get string description for tunnel state.
211 * @param s Tunnel state.
213 * @return String representation.
216 GNUNET_MESH_DEBUG_TS2S (enum MeshTunnelState s)
218 static char buf[128];
222 case MESH_TUNNEL_NEW:
223 return "MESH_TUNNEL_NEW";
224 case MESH_TUNNEL_SEARCHING:
225 return "MESH_TUNNEL_SEARCHING";
226 case MESH_TUNNEL_WAITING:
227 return "MESH_TUNNEL_WAITING";
228 case MESH_TUNNEL_READY:
229 return "MESH_TUNNEL_READY";
230 case MESH_TUNNEL_RECONNECTING:
231 return "MESH_TUNNEL_RECONNECTING";
234 sprintf (buf, "%u (UNKNOWN STATE)", s);
241 * Pick a connection on which send the next data message.
243 * @param t Tunnel on which to send the message.
244 * @param fwd Is this a fwd message?
246 * @return The connection on which to send the next message.
248 static struct MeshConnection *
249 tunnel_get_connection (struct MeshTunnel2 *t, int fwd)
251 struct MeshConnection *c;
252 struct MeshConnection *best;
253 struct MeshFlowControl *fc;
254 unsigned int lowest_q;
256 LOG (GNUNET_ERROR_TYPE_DEBUG, "tunnel_get_connection %s\n",
260 for (c = t->connection_head; NULL != c; c = c->next)
262 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s: %u\n",
263 GNUNET_h2s (GMC_get_id (c)), c->state);
264 if (MESH_CONNECTION_READY == c->state)
266 fc = fwd ? &c->fwd_fc : &c->bck_fc;
272 LOG (GNUNET_ERROR_TYPE_DEBUG, " q_n %u, \n", fc->queue_n);
273 if (fc->queue_n < lowest_q)
276 lowest_q = fc->queue_n;
285 * Get the total buffer space for a tunnel.
288 * @param fwd Is this for FWD traffic?
290 * @return Buffer space offered by all connections in the tunnel.
293 tunnel_get_buffer (struct MeshTunnel2 *t, int fwd)
295 struct MeshConnection *c;
296 struct MeshFlowControl *fc;
299 c = t->connection_head;
302 /* If terminal, return biggest channel buffer */
303 if (NULL == c || GMC_is_terminal (c, fwd))
305 struct MeshChannel *ch;
308 if (NULL == t->channel_head)
311 for (ch = t->channel_head; NULL != ch; ch = ch->next)
313 ch_buf = GMCH_get_buffer (ch, fwd);
320 /* If not terminal, return sum of connection buffers */
323 if (c->state != MESH_CONNECTION_READY)
329 fc = fwd ? &c->fwd_fc : &c->bck_fc;
330 buffer += fc->queue_max - fc->queue_n;
339 * Send all cached messages that we can, tunnel is online.
341 * @param t Tunnel that holds the messages.
342 * @param fwd Is this fwd?
345 tunnel_send_queued_data (struct MeshTunnel2 *t, int fwd)
347 struct MeshTunnelQueue *tq;
348 struct MeshTunnelQueue *next;
351 LOG (GNUNET_ERROR_TYPE_DEBUG,
352 "tunnel_send_queued_data on tunnel %s\n",
354 room = tunnel_get_buffer (t, fwd);
355 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
356 for (tq = t->tq_head; NULL != tq && room > 0; tq = next)
360 GNUNET_CONTAINER_DLL_remove (t->tq_head, t->tq_tail, tq);
361 GMCH_send_prebuilt_message ((struct GNUNET_MessageHeader *) &tq[1],
370 * Cache a message to be sent once tunnel is online.
372 * @param t Tunnel to hold the message.
373 * @param ch Channel the message is about.
374 * @param msg Message itself (copy will be made).
375 * @param fwd Is this fwd?
378 GMT_queue_data (struct MeshTunnel2 *t,
379 struct MeshChannel *ch,
380 struct GNUNET_MessageHeader *msg,
383 struct MeshTunnelQueue *tq;
384 uint16_t size = ntohs (msg->size);
386 tq = GNUNET_malloc (sizeof (struct MeshTunnelQueue) + size);
389 memcpy (&tq[1], msg, size);
390 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tq);
392 if (MESH_TUNNEL_READY == t->state)
393 tunnel_send_queued_data (t, fwd);
398 /******************************************************************************/
399 /******************************** API ***********************************/
400 /******************************************************************************/
403 * Initialize the tunnel subsystem.
405 * @param c Configuration handle.
406 * @param id Peer identity.
407 * @param key ECC private key, to derive all other keys and do crypto.
410 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
411 const struct GNUNET_PeerIdentity *id,
412 const struct GNUNET_CRYPTO_EccPrivateKey *key)
415 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
418 LOG_config_invalid (GNUNET_ERROR_TYPE_WARNING,
419 "MESH", "DEFAULT_TTL", "USING DEFAULT");
423 my_private_key = key;
424 my_short_id = GNUNET_PEER_intern (my_full_id);
429 * Shut down the tunnel subsystem.
434 GNUNET_PEER_change_rc (my_short_id, -1);
444 struct MeshTunnel2 *t;
446 t = GNUNET_new (struct MeshTunnel2);
448 t->next_local_chid = GNUNET_MESH_LOCAL_CHANNEL_ID_SERV;
450 // GNUNET_CONTAINER_multihashmap_put (tunnels, tid, t,
451 // GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
454 // tunnel_destroy (t);
458 // char salt[] = "salt";
459 // GNUNET_CRYPTO_kdf (&t->e_key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
460 // salt, sizeof (salt),
461 // &t->e_key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
462 // &my_full_id, sizeof (struct GNUNET_PeerIdentity),
463 // GNUNET_PEER_resolve2 (t->peer->id), sizeof (struct GNUNET_PeerIdentity),
465 // GNUNET_CRYPTO_kdf (&t->d_key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
466 // salt, sizeof (salt),
467 // &t->d_key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
468 // GNUNET_PEER_resolve2 (t->peer->id), sizeof (struct GNUNET_PeerIdentity),
469 // &my_full_id, sizeof (struct GNUNET_PeerIdentity),
478 * Change the tunnel state.
480 * @param t Tunnel whose state to change.
481 * @param state New state.
484 GMT_change_state (struct MeshTunnel2* t, enum MeshTunnelState state)
488 LOG (GNUNET_ERROR_TYPE_DEBUG,
489 "Tunnel %s state was %s\n",
491 GNUNET_MESH_DEBUG_TS2S (t->state));
492 LOG (GNUNET_ERROR_TYPE_DEBUG,
493 "Tunnel %s state is now %s\n",
495 GNUNET_MESH_DEBUG_TS2S (state));
501 * Add a connection to a tunnel.
504 * @param c Connection.
507 GMT_add_connection (struct MeshTunnel2 *t, struct MeshConnection *c)
509 struct MeshConnection *aux;
511 for (aux = t->connection_head; aux != NULL; aux = aux->next)
514 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, c);
521 * Tunnel is empty: destroy it.
523 * Notifies all connections about the destruction.
525 * @param t Tunnel to destroy.
528 GMT_destroy_empty (struct MeshTunnel2 *t)
530 struct MeshConnection *c;
532 for (c = t->connection_head; NULL != c; c = c->next)
534 if (GNUNET_NO == c->destroy)
535 GMC_send_destroy (c);
538 if (0 == t->pending_messages)
541 t->destroy = GNUNET_YES;
546 * Destroy tunnel if empty (no more channels).
548 * @param t Tunnel to destroy if empty.
551 GMT_destroy_if_empty (struct MeshTunnel2 *t)
553 if (1 < GMCH_count (t->channel_head))
556 GMT_destroy_empty (t);
562 * Destroy the tunnel.
564 * This function does not generate any warning traffic to clients or peers.
567 * Cancel messages belonging to this tunnel queued to neighbors.
568 * Free any allocated resources linked to the tunnel.
570 * @param t The tunnel to destroy.
573 GMT_destroy (struct MeshTunnel2 *t)
575 struct MeshConnection *c;
576 struct MeshConnection *next;
581 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n",
584 // if (GNUNET_YES != GNUNET_CONTAINER_multihashmap_remove (tunnels, &t->id, t))
587 for (c = t->connection_head; NULL != c; c = next)
593 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
594 GMP_set_tunnel (t->peer, NULL);
600 * Demultiplex by message type and call appropriate handler for a message
601 * towards a channel of a local tunnel.
603 * @param t Tunnel this message came on.
604 * @param msgh Message header.
605 * @param fwd Is this message fwd?
608 GMT_handle_decrypted (struct MeshTunnel2 *t,
609 const struct GNUNET_MessageHeader *msgh,
612 switch (ntohs (msgh->type))
614 case GNUNET_MESSAGE_TYPE_MESH_DATA:
615 /* Don't send hop ACK, wait for client to ACK */
616 GMCH_handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
619 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
620 GMCH_handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
623 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
624 GMCH_handle_create (t,
625 (struct GNUNET_MESH_ChannelCreate *) msgh,
629 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
631 (struct GNUNET_MESH_ChannelManage *) msgh,
635 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
636 GMCH_handle_destroy (t,
637 (struct GNUNET_MESH_ChannelManage *) msgh,
643 LOG (GNUNET_ERROR_TYPE_DEBUG,
644 "end-to-end message not known (%u)\n",
651 * Notifies a tunnel that a connection has broken that affects at least
652 * some of its peers. Sends a notification towards the root of the tree.
653 * In case the peer is the owner of the tree, notifies the client that owns
654 * the tunnel and tries to reconnect.
656 * FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME
658 * @param t Tunnel affected.
659 * @param p1 Peer that got disconnected from p2.
660 * @param p2 Peer that got disconnected from p1.
662 * @return Short ID of the peer disconnected (either p1 or p2).
663 * 0 if the tunnel remained unaffected.
666 GMT_notify_connection_broken (struct MeshTunnel2* t,
667 GNUNET_PEER_Id p1, GNUNET_PEER_Id p2)
669 // if (myid != p1 && myid != p2) FIXME
674 // if (tree_get_predecessor (t->tree) != 0)
676 // /* We are the peer still connected, notify owner of the disconnection. */
677 // struct GNUNET_MESH_PathBroken msg;
678 // struct GNUNET_PeerIdentity neighbor;
680 // msg.header.size = htons (sizeof (msg));
681 // msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_PATH_BROKEN);
682 // GNUNET_PEER_resolve (t->id.oid, &msg.oid);
683 // msg.tid = htonl (t->id.tid);
684 // msg.peer1 = my_full_id;
685 // GNUNET_PEER_resolve (pid, &msg.peer2);
686 // GNUNET_PEER_resolve (tree_get_predecessor (t->tree), &neighbor);
687 // send_prebuilt_message (&msg.header, &neighbor, t);
693 * @brief Use the given path for the tunnel.
694 * Update the next and prev hops (and RCs).
695 * (Re)start the path refresh in case the tunnel is locally owned.
697 * @param t Tunnel to update.
698 * @param p Path to use.
700 * @return Connection created.
702 struct MeshConnection *
703 GMT_use_path (struct MeshTunnel2 *t, struct MeshPeerPath *p)
705 struct MeshConnection *c;
706 struct GNUNET_HashCode cid;
707 unsigned int own_pos;
709 if (NULL == t || NULL == p)
715 for (own_pos = 0; own_pos < p->length; own_pos++)
717 if (p->peers[own_pos] == my_short_id)
720 if (own_pos > p->length - 1)
726 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
727 c = GMC_new (&cid, t, p, own_pos);
728 GNUNET_CONTAINER_DLL_insert (t->connection_head, t->connection_tail, c);
734 * FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME
735 * Encrypt data with the tunnel key.
737 * @param t Tunnel whose key to use.
738 * @param dst Destination for the encrypted data.
739 * @param src Source of the plaintext.
740 * @param size Size of the plaintext.
741 * @param iv Initialization Vector to use.
742 * @param fwd Is this a fwd message?
745 GMT_encrypt (struct MeshTunnel2 *t,
746 void *dst, const void *src,
747 size_t size, uint64_t iv, int fwd)
749 memcpy (dst, src, size);
754 * FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME
755 * Decrypt data with the tunnel key.
757 * @param t Tunnel whose key to use.
758 * @param dst Destination for the plaintext.
759 * @param src Source of the encrypted data.
760 * @param size Size of the encrypted data.
761 * @param iv Initialization Vector to use.
762 * @param fwd Is this a fwd message?
765 GMT_decrypt (struct MeshTunnel2 *t,
766 void *dst, const void *src,
767 size_t size, uint64_t iv, int fwd)
769 memcpy (dst, src, size);
774 * Count established (ready) connections of a tunnel.
776 * @param t Tunnel on which to send the message.
778 * @return Number of connections.
781 GMT_count_connections (struct MeshTunnel2 *t)
783 return GMC_count (t->connection_head);
788 * Sends an already built message on a tunnel, choosing the best connection.
790 * @param message Message to send. Function modifies it.
791 * @param t Tunnel on which this message is transmitted.
792 * @param ch Channel on which this message is transmitted.
793 * @param fwd Is this a fwd message?
796 GMT_send_prebuilt_message (struct GNUNET_MESH_Encrypted *msg,
797 struct MeshTunnel2 *t,
798 struct MeshChannel *ch,
801 struct MeshConnection *c;
804 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send on Tunnel %s\n",
806 c = tunnel_get_connection (t, fwd);
809 GNUNET_break (GNUNET_YES == t->destroy);
812 type = ntohs (msg->header.type);
815 case GNUNET_MESSAGE_TYPE_MESH_FWD:
816 case GNUNET_MESSAGE_TYPE_MESH_BCK:
817 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
818 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
819 msg->cid = *GMC_get_id (c);
820 msg->ttl = htonl (default_ttl);
823 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
824 GNUNET_MESH_DEBUG_M2S (type));
829 GMC_send_prebuilt_message (&msg->header, c, ch, fwd);