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 * Check that a ephemeral key message s well formed and correctly signed.
296 * @param t Tunnel on which the message came.
297 * @param msg The ephemeral key message.
299 * @return GNUNET_OK if message is fine, GNUNET_SYSERR otherwise.
302 check_ephemeral (struct MeshTunnel3 *t,
303 const struct GNUNET_MESH_KX_Ephemeral *msg)
305 /* Check message size */
306 if (ntohs (msg->header.size) != sizeof (struct GNUNET_MESH_KX_Ephemeral))
307 return GNUNET_SYSERR;
309 /* Check signature size */
310 if (ntohl (msg->purpose.size) != ephemeral_purpose_size ())
311 return GNUNET_SYSERR;
314 if (0 != memcmp (&msg->origin_identity,
315 GMP_get_id (t->peer),
316 sizeof (struct GNUNET_PeerIdentity)))
317 return GNUNET_SYSERR;
319 /* Check signature */
321 GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_MESH_KX,
324 &msg->origin_identity.public_key))
325 return GNUNET_SYSERR;
332 * Encrypt data with the tunnel key.
334 * @param t Tunnel whose key to use.
335 * @param dst Destination for the encrypted data.
336 * @param src Source of the plaintext. Can overlap with @c dst.
337 * @param size Size of the plaintext.
338 * @param iv Initialization Vector to use.
341 t_encrypt (struct MeshTunnel3 *t,
342 void *dst, const void *src,
343 size_t size, uint32_t iv)
345 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
347 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->e_key, &iv, sizeof (uint32_t), NULL);
348 return GNUNET_CRYPTO_symmetric_encrypt (src, size, &t->e_key, &siv, dst);
353 * Decrypt data with the tunnel key.
355 * @param t Tunnel whose key to use.
356 * @param dst Destination for the plaintext.
357 * @param src Source of the encrypted data. Can overlap with @c dst.
358 * @param size Size of the encrypted data.
359 * @param iv Initialization Vector to use.
362 t_decrypt (struct MeshTunnel3 *t,
363 void *dst, const void *src,
364 size_t size, uint32_t iv)
366 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
368 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->e_key, &iv, sizeof (uint32_t), NULL);
369 return GNUNET_CRYPTO_symmetric_decrypt (src, size, &t->d_key, &siv, dst);
374 * Create key material by doing ECDH on the local and remote ephemeral keys.
376 * @param key_material Where to store the key material.
377 * @param ephemeral_key Peer's public ephemeral key.
380 derive_key_material (struct GNUNET_HashCode *key_material,
381 const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key)
384 GNUNET_CRYPTO_ecc_ecdh (my_ephemeral_key,
393 * Create a symmetic key from the identities of both ends and the key material
396 * @param key Destination for the generated key.
397 * @param sender ID of the peer that will encrypt with @c key.
398 * @param receiver ID of the peer that will decrypt with @c key.
399 * @param key_material Hash created with ECDH with the ephemeral keys.
402 derive_symmertic (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
403 const struct GNUNET_PeerIdentity *sender,
404 const struct GNUNET_PeerIdentity *receiver,
405 const struct GNUNET_HashCode *key_material)
407 const char salt[] = "MESH kx salt";
409 GNUNET_CRYPTO_kdf (key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
411 key_material, sizeof (struct GNUNET_HashCode),
412 sender, sizeof (struct GNUNET_PeerIdentity),
413 receiver, sizeof (struct GNUNET_PeerIdentity),
418 * Pick a connection on which send the next data message.
420 * @param t Tunnel on which to send the message.
422 * @return The connection on which to send the next message.
424 static struct MeshConnection *
425 tunnel_get_connection (struct MeshTunnel3 *t)
427 struct MeshTConnection *iter;
428 struct MeshConnection *best;
430 unsigned int lowest_q;
432 LOG (GNUNET_ERROR_TYPE_DEBUG, "tunnel_get_connection %s\n", GMP_2s (t->peer));
435 for (iter = t->connection_head; NULL != iter; iter = iter->next)
437 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s: %u\n",
438 GNUNET_h2s (GMC_get_id (iter->c)), GMC_get_state (iter->c));
439 if (MESH_CONNECTION_READY == GMC_get_state (iter->c))
441 qn = GMC_get_qn (iter->c, GMC_is_origin (iter->c, GNUNET_YES));
442 LOG (GNUNET_ERROR_TYPE_DEBUG, " q_n %u, \n", qn);
455 * Send all cached messages that we can, tunnel is online.
457 * @param t Tunnel that holds the messages.
458 * @param fwd Is this fwd?
461 send_queued_data (struct MeshTunnel3 *t, int fwd)
463 struct MeshTunnelQueue *tq;
464 struct MeshTunnelQueue *next;
467 LOG (GNUNET_ERROR_TYPE_DEBUG,
468 "GMT_send_queued_data on tunnel %s\n",
471 if (NULL == t->channel_head ||
472 GNUNET_NO == GMCH_is_origin (t->channel_head->ch, fwd))
475 room = GMT_get_buffer (t, fwd);
476 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
477 for (tq = t->tq_head; NULL != tq && room > 0; tq = next)
479 LOG (GNUNET_ERROR_TYPE_DEBUG, " data on channel %s\n", GMCH_2s (tq->ch));
482 GNUNET_CONTAINER_DLL_remove (t->tq_head, t->tq_tail, tq);
483 GMCH_send_prebuilt_message ((struct GNUNET_MessageHeader *) &tq[1],
488 LOG (GNUNET_ERROR_TYPE_DEBUG,
489 "GMT_send_queued_data end\n",
497 * Cache a message to be sent once tunnel is online.
499 * @param t Tunnel to hold the message.
500 * @param ch Channel the message is about.
501 * @param msg Message itself (copy will be made).
504 queue_data (struct MeshTunnel3 *t,
505 struct MeshChannel *ch,
506 const struct GNUNET_MessageHeader *msg)
508 struct MeshTunnelQueue *tq;
509 uint16_t size = ntohs (msg->size);
511 if (MESH_TUNNEL3_READY == t->state)
517 tq = GNUNET_malloc (sizeof (struct MeshTunnelQueue) + size);
520 memcpy (&tq[1], msg, size);
521 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tq);
527 * Sends key exchange message on a tunnel, choosing the best connection.
528 * Should not be called on loopback tunnels.
530 * @param t Tunnel on which this message is transmitted.
531 * @param message Message to send. Function modifies it.
534 send_kx (struct MeshTunnel3 *t,
535 const struct GNUNET_MessageHeader *message)
537 struct MeshConnection *c;
538 struct GNUNET_MESH_KX *msg;
539 size_t size = ntohs (message->size);
540 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
544 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
546 /* Avoid loopback. */
547 if (myid == GMP_get_short_id (t->peer))
549 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
554 /* Must have a connection. */
555 if (NULL == t->connection_head)
561 msg = (struct GNUNET_MESH_KX *) cbuf;
562 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
563 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
564 c = tunnel_get_connection (t);
567 GNUNET_break (GNUNET_YES == t->destroy);
570 type = ntohs (message->type);
573 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
574 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
575 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
576 msg->cid = *GMC_get_id (c);
577 msg->reserved = htonl (0);
578 memcpy (&msg[1], message, size);
581 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
582 GNUNET_MESH_DEBUG_M2S (type));
586 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
587 GMC_send_prebuilt_message (&msg->header, c, fwd);
592 * Send the ephemeral key on a tunnel.
594 * @param t Tunnel on which to send the key.
597 send_ephemeral (struct MeshTunnel3 *t)
599 kx_msg.sender_status = htonl (t->state);
601 send_kx (t, &kx_msg.header);
605 * Send a ping message on a tunnel.
607 * @param t Tunnel on which to send the ping.
610 send_ping (struct MeshTunnel3 *t)
612 struct GNUNET_MESH_KX_Ping msg;
614 msg.header.size = htons (sizeof (msg));
615 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
616 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
617 msg.target = *GMP_get_id (t->peer);
618 msg.nonce = t->kx_ctx->challenge;
619 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
621 send_kx (t, &msg.header);
626 * Send a pong message on a tunnel.
628 * @param t Tunnel on which to send the pong.
629 * @param challenge Value sent in the ping that we have to send back.
632 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
634 struct GNUNET_MESH_KX_Pong msg;
636 msg.header.size = htons (sizeof (msg));
637 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
638 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
639 msg.nonce = challenge;
640 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
642 send_kx (t, &msg.header);
647 * Initiate a rekey with the remote peer.
649 * @param cls Closure (tunnel).
650 * @param tc TaskContext.
653 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
655 struct MeshTunnel3 *t = cls;
657 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
659 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
662 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
663 t->kx_ctx->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
665 t->kx_ctx->d_key_old = t->d_key;
667 if (MESH_TUNNEL3_READY == t->state)
670 t->state = MESH_TUNNEL3_REKEY;
672 else if (MESH_TUNNEL3_WAITING == t->state)
674 t->state = MESH_TUNNEL3_KEY_SENT;
678 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->state);
681 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
686 * Out ephemeral key has changed, create new session key on all tunnels.
688 * @param cls Closure (size of the hashmap).
689 * @param key Current public key.
690 * @param value Value in the hash map (tunnel).
692 * @return #GNUNET_YES, so we should continue to iterate,
695 rekey_iterator (void *cls,
696 const struct GNUNET_PeerIdentity *key,
699 struct MeshTunnel3 *t = value;
700 struct GNUNET_TIME_Relative delay;
704 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
707 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
708 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
709 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
716 * Create a new ephemeral key and key message, schedule next rekeying.
718 * @param cls Closure (unused).
719 * @param tc TaskContext.
722 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
724 struct GNUNET_TIME_Absolute time;
727 rekey_task = GNUNET_SCHEDULER_NO_TASK;
729 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
732 GNUNET_free_non_null (my_ephemeral_key);
733 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
735 time = GNUNET_TIME_absolute_get ();
736 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
737 time = GNUNET_TIME_absolute_add (time, rekey_period);
738 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
739 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
740 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
742 GNUNET_assert (GNUNET_OK ==
743 GNUNET_CRYPTO_eddsa_sign (my_private_key,
747 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
748 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
750 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
755 * Demultiplex data per channel and call appropriate channel handler.
757 * @param t Tunnel on which the data came.
758 * @param msg Data message.
759 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
760 * #GNUNET_YES if message is FWD on the respective channel (loopback)
761 * #GNUNET_NO if message is BCK on the respective channel (loopback)
762 * #GNUNET_SYSERR if message on a one-ended channel (remote)
765 handle_data (struct MeshTunnel3 *t,
766 const struct GNUNET_MESH_Data *msg,
769 struct MeshChannel *ch;
774 size = ntohs (msg->header.size);
776 sizeof (struct GNUNET_MESH_Data) +
777 sizeof (struct GNUNET_MessageHeader))
782 type = ntohs (msg->header.type);
783 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message\n",
784 GNUNET_MESH_DEBUG_M2S (type));
785 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
786 GNUNET_MESH_DEBUG_M2S (ntohs (msg[1].header.type)));
789 ch = GMT_get_channel (t, ntohl (msg->chid));
792 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
794 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
799 GMT_change_state (t, MESH_TUNNEL3_READY);
800 GMCH_handle_data (ch, msg, fwd);
805 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
807 * @param t Tunnel on which the DATA ACK came.
808 * @param msg DATA ACK message.
809 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
810 * #GNUNET_YES if message is FWD on the respective channel (loopback)
811 * #GNUNET_NO if message is BCK on the respective channel (loopback)
812 * #GNUNET_SYSERR if message on a one-ended channel (remote)
815 handle_data_ack (struct MeshTunnel3 *t,
816 const struct GNUNET_MESH_DataACK *msg,
819 struct MeshChannel *ch;
823 size = ntohs (msg->header.size);
824 if (size != sizeof (struct GNUNET_MESH_DataACK))
831 ch = GMT_get_channel (t, ntohl (msg->chid));
834 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
836 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
841 GMCH_handle_data_ack (ch, msg, fwd);
846 * Handle channel create.
848 * @param t Tunnel on which the data came.
849 * @param msg Data message.
852 handle_ch_create (struct MeshTunnel3 *t,
853 const struct GNUNET_MESH_ChannelCreate *msg)
855 struct MeshChannel *ch;
859 size = ntohs (msg->header.size);
860 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
867 ch = GMT_get_channel (t, ntohl (msg->chid));
870 /* Probably a retransmission, safe to ignore */
871 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
875 ch = GMCH_handle_create (t, msg);
877 GMT_add_channel (t, ch);
882 * Handle a CHANNEL ACK (SYNACK/ACK).
884 * @param t Tunnel on which the CHANNEL ACK came.
885 * @param msg CHANNEL 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_ch_ack (struct MeshTunnel3 *t,
893 const struct GNUNET_MESH_ChannelManage *msg,
896 struct MeshChannel *ch;
900 size = ntohs (msg->header.size);
901 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
908 ch = GMT_get_channel (t, ntohl (msg->chid));
911 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
913 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
918 GMCH_handle_ack (ch, msg, fwd);
924 * Handle a channel destruction message.
926 * @param t Tunnel on which the message came.
927 * @param msg Channel destroy message.
928 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
929 * #GNUNET_YES if message is FWD on the respective channel (loopback)
930 * #GNUNET_NO if message is BCK on the respective channel (loopback)
931 * #GNUNET_SYSERR if message on a one-ended channel (remote)
934 handle_ch_destroy (struct MeshTunnel3 *t,
935 const struct GNUNET_MESH_ChannelManage *msg,
938 struct MeshChannel *ch;
942 size = ntohs (msg->header.size);
943 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
950 ch = GMT_get_channel (t, ntohl (msg->chid));
953 /* Probably a retransmission, safe to ignore */
957 GMCH_handle_destroy (ch, msg, fwd);
962 * The peer's ephemeral key has changed: update the symmetrical keys.
964 * @param t Tunnel this message came on.
965 * @param msg Key eXchange message.
968 handle_ephemeral (struct MeshTunnel3 *t,
969 const struct GNUNET_MESH_KX_Ephemeral *msg)
971 struct GNUNET_HashCode km;
972 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
974 if (GNUNET_OK != check_ephemeral (t, msg))
979 derive_key_material (&km, &msg->ephemeral_key);
980 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
981 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
982 if (MESH_TUNNEL3_KEY_SENT == t->state)
985 t->state = MESH_TUNNEL3_PING_SENT;
991 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
992 * Answer with by retransmitting the challenge with the "opposite" key.
994 * @param t Tunnel this message came on.
995 * @param msg Key eXchange Ping message.
998 handle_ping (struct MeshTunnel3 *t,
999 const struct GNUNET_MESH_KX_Ping *msg)
1001 struct GNUNET_MESH_KX_Ping res;
1003 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1004 t_decrypt (t, &res.target, &msg->target, ping_encryption_size(), msg->iv);
1005 if (0 != memcmp (&my_full_id, &msg->target, sizeof (my_full_id)))
1008 LOG (GNUNET_ERROR_TYPE_DEBUG, " at %s\n", GNUNET_i2s (&my_full_id));
1009 LOG (GNUNET_ERROR_TYPE_DEBUG, " for %s\n", GNUNET_i2s (&msg->target));
1013 send_pong (t, res.iv);
1018 * Peer has answer to our challenge.
1019 * If answer is successful, consider the key exchange finished and clean
1020 * up all related state.
1022 * @param t Tunnel this message came on.
1023 * @param msg Key eXchange Pong message.
1026 handle_pong (struct MeshTunnel3 *t,
1027 const struct GNUNET_MESH_KX_Pong *msg)
1031 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1032 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1034 GNUNET_break_op (0);
1037 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1039 if (challenge != t->kx_ctx->challenge)
1041 LOG (GNUNET_ERROR_TYPE_DEBUG,
1042 "Wrong PONG challenge: %u. Expected: %u.\n",
1043 challenge, t->kx_ctx->challenge);
1044 GNUNET_break_op (0);
1047 GNUNET_SCHEDULER_cancel (t->rekey_task);
1048 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1049 GNUNET_free (t->kx_ctx);
1051 t->state = MESH_TUNNEL3_READY;
1052 send_queued_data (t, GNUNET_YES);
1053 send_queued_data (t, GNUNET_NO);
1058 * Demultiplex by message type and call appropriate handler for a message
1059 * towards a channel of a local tunnel.
1061 * @param t Tunnel this message came on.
1062 * @param msgh Message header.
1063 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1064 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1065 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1066 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1069 handle_decrypted (struct MeshTunnel3 *t,
1070 const struct GNUNET_MessageHeader *msgh,
1075 type = ntohs (msgh->type);
1076 LOG (GNUNET_ERROR_TYPE_DEBUG,
1077 "Got a %s message!\n",
1078 GNUNET_MESH_DEBUG_M2S (type));
1082 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1083 /* Don't send hop ACK, wait for client to ACK */
1084 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1087 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1088 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1091 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1092 handle_ch_create (t,
1093 (struct GNUNET_MESH_ChannelCreate *) msgh);
1096 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1098 (struct GNUNET_MESH_ChannelManage *) msgh,
1102 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1103 handle_ch_destroy (t,
1104 (struct GNUNET_MESH_ChannelManage *) msgh,
1109 GNUNET_break_op (0);
1110 LOG (GNUNET_ERROR_TYPE_DEBUG,
1111 "end-to-end message not known (%u)\n",
1112 ntohs (msgh->type));
1116 /******************************************************************************/
1117 /******************************** API ***********************************/
1118 /******************************************************************************/
1121 * Decrypt and demultiplex by message type. Call appropriate handler
1122 * for every message.
1124 * @param t Tunnel this message came on.
1125 * @param msg Encrypted message.
1128 GMT_handle_encrypted (struct MeshTunnel3 *t,
1129 const struct GNUNET_MESH_Encrypted *msg)
1131 size_t size = ntohs (msg->header.size);
1132 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1133 size_t decrypted_size;
1134 char cbuf [payload_size];
1135 struct GNUNET_MessageHeader *msgh;
1138 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1140 while (off < decrypted_size)
1142 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1143 handle_decrypted (t, msgh, GNUNET_SYSERR);
1144 off += ntohs (msgh->size);
1150 * Demultiplex an encapsulated KX message by message type.
1152 * @param t Tunnel on which the message came.
1153 * @param message Payload of KX message.
1156 GMT_handle_kx (struct MeshTunnel3 *t,
1157 const struct GNUNET_MessageHeader *message)
1161 type = ntohs (message->type);
1162 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1165 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1166 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1169 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1170 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1173 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1174 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1178 GNUNET_break_op (0);
1179 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1185 * Initialize the tunnel subsystem.
1187 * @param c Configuration handle.
1188 * @param key ECC private key, to derive all other keys and do crypto.
1191 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1192 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1194 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1196 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1199 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1200 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1204 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1207 rekey_period = GNUNET_TIME_UNIT_DAYS;
1210 my_private_key = key;
1211 kx_msg.header.size = htons (sizeof (kx_msg));
1212 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1213 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1214 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1215 kx_msg.origin_identity = my_full_id;
1216 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1218 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1223 * Shut down the tunnel subsystem.
1228 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1230 GNUNET_SCHEDULER_cancel (rekey_task);
1231 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1233 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1240 * @param destination Peer this tunnel is towards.
1242 struct MeshTunnel3 *
1243 GMT_new (struct MeshPeer *destination)
1245 struct MeshTunnel3 *t;
1247 t = GNUNET_new (struct MeshTunnel3);
1249 t->peer = destination;
1252 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1253 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1264 * Change the tunnel state.
1266 * @param t Tunnel whose state to change.
1267 * @param state New state.
1270 GMT_change_state (struct MeshTunnel3* t, enum MeshTunnel3State state)
1274 LOG (GNUNET_ERROR_TYPE_DEBUG,
1275 "Tunnel %s state was %s\n",
1277 GMT_state2s (t->state));
1278 LOG (GNUNET_ERROR_TYPE_DEBUG,
1279 "Tunnel %s state is now %s\n",
1281 GMT_state2s (state));
1282 if (myid != GMP_get_short_id (t->peer) &&
1283 MESH_TUNNEL3_WAITING == t->state && MESH_TUNNEL3_READY == state)
1285 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1286 rekey_tunnel (t, NULL);
1287 LOG (GNUNET_ERROR_TYPE_DEBUG,
1288 "Tunnel %s state is now %s\n",
1290 GMT_state2s (t->state));
1296 if (MESH_TUNNEL3_READY == state && 3 <= GMT_count_connections (t))
1298 GMP_stop_search (t->peer);
1304 * Add a connection to a tunnel.
1307 * @param c Connection.
1310 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1312 struct MeshTConnection *aux;
1314 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1318 aux = GNUNET_new (struct MeshTConnection);
1320 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1325 * Remove a connection from a tunnel.
1328 * @param c Connection.
1331 GMT_remove_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1333 struct MeshTConnection *aux;
1335 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1338 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1346 * Add a channel to a tunnel.
1349 * @param ch Channel.
1352 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1354 struct MeshTChannel *aux;
1356 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1358 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1360 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1365 aux = GNUNET_new (struct MeshTChannel);
1367 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1368 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1373 * Remove a channel from a tunnel.
1376 * @param ch Channel.
1379 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1381 struct MeshTChannel *aux;
1383 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1384 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1388 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1389 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1398 * Search for a channel by global ID.
1400 * @param t Tunnel containing the channel.
1401 * @param chid Public channel number.
1403 * @return channel handler, NULL if doesn't exist
1405 struct MeshChannel *
1406 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1408 struct MeshTChannel *iter;
1413 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1415 if (GMCH_get_id (iter->ch) == chid)
1419 return NULL == iter ? NULL : iter->ch;
1424 * Tunnel is empty: destroy it.
1426 * Notifies all connections about the destruction.
1428 * @param t Tunnel to destroy.
1431 GMT_destroy_empty (struct MeshTunnel3 *t)
1433 struct MeshTConnection *iter;
1435 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1437 GMC_send_destroy (iter->c);
1440 t->destroy = GNUNET_YES;
1445 * Destroy tunnel if empty (no more channels).
1447 * @param t Tunnel to destroy if empty.
1450 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1452 if (1 < GMT_count_channels (t))
1455 GMT_destroy_empty (t);
1460 * Destroy the tunnel.
1462 * This function does not generate any warning traffic to clients or peers.
1465 * Cancel messages belonging to this tunnel queued to neighbors.
1466 * Free any allocated resources linked to the tunnel.
1468 * @param t The tunnel to destroy.
1471 GMT_destroy (struct MeshTunnel3 *t)
1473 struct MeshTConnection *iter;
1474 struct MeshTConnection *next;
1479 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
1481 // if (GNUNET_YES != GNUNET_CONTAINER_multihashmap_remove (tunnels, &t->id, t))
1482 // GNUNET_break (0);
1484 for (iter = t->connection_head; NULL != iter; iter = next)
1487 GMC_destroy (iter->c);
1490 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
1491 GMP_set_tunnel (t->peer, NULL);
1493 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1494 GNUNET_SCHEDULER_cancel (t->rekey_task);
1501 * @brief Use the given path for the tunnel.
1502 * Update the next and prev hops (and RCs).
1503 * (Re)start the path refresh in case the tunnel is locally owned.
1505 * @param t Tunnel to update.
1506 * @param p Path to use.
1508 * @return Connection created.
1510 struct MeshConnection *
1511 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
1513 struct MeshConnection *c;
1514 struct GNUNET_HashCode cid;
1515 unsigned int own_pos;
1517 if (NULL == t || NULL == p)
1523 for (own_pos = 0; own_pos < p->length; own_pos++)
1525 if (p->peers[own_pos] == myid)
1528 if (own_pos > p->length - 1)
1534 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
1535 c = GMC_new (&cid, t, p, own_pos);
1536 GMT_add_connection (t, c);
1542 * Count established (ready) connections of a tunnel.
1544 * @param t Tunnel on which to count.
1546 * @return Number of connections.
1549 GMT_count_connections (struct MeshTunnel3 *t)
1551 struct MeshTConnection *iter;
1554 for (count = 0, iter = t->connection_head;
1556 iter = iter->next, count++);
1562 * Count channels of a tunnel.
1564 * @param t Tunnel on which to count.
1566 * @return Number of channels.
1569 GMT_count_channels (struct MeshTunnel3 *t)
1571 struct MeshTChannel *iter;
1574 for (count = 0, iter = t->channel_head;
1576 iter = iter->next, count++) /* skip */;
1583 * Get the state of a tunnel.
1587 * @return Tunnel's state.
1589 enum MeshTunnel3State
1590 GMT_get_state (struct MeshTunnel3 *t)
1593 return (enum MeshTunnel3State) -1;
1598 * Get the total buffer space for a tunnel.
1600 * If terminal, use the biggest channel buffer (or 64) if no channel exists.
1601 * If not terminal, use the sum of all connection buffers.
1604 * @param fwd Is this for FWD traffic?
1606 * @return Buffer space offered by all entities (c/ch) in the tunnel.
1609 GMT_get_buffer (struct MeshTunnel3 *t, int fwd)
1611 struct MeshTConnection *iter;
1612 unsigned int buffer;
1614 iter = t->connection_head;
1617 /* If terminal, return biggest channel buffer */
1618 if (NULL == iter || GMC_is_terminal (iter->c, fwd))
1620 struct MeshTChannel *iter_ch;
1621 unsigned int ch_buf;
1623 if (NULL == t->channel_head)
1625 /* Probably getting buffer for a channel create/handshake. */
1629 for (iter_ch = t->channel_head; NULL != iter_ch; iter_ch = iter_ch->next)
1631 ch_buf = GMCH_get_buffer (iter_ch->ch, fwd);
1632 if (ch_buf > buffer)
1638 /* If not terminal, return sum of connection buffers */
1639 while (NULL != iter)
1641 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
1647 buffer += GMC_get_buffer (iter->c, fwd);
1656 * Get the tunnel's destination.
1660 * @return ID of the destination peer.
1662 const struct GNUNET_PeerIdentity *
1663 GMT_get_destination (struct MeshTunnel3 *t)
1665 return GMP_get_id (t->peer);
1670 * Get the tunnel's next free global channel ID.
1674 * @return GID of a channel free to use.
1677 GMT_get_next_chid (struct MeshTunnel3 *t)
1679 MESH_ChannelNumber chid;
1681 while (NULL != GMT_get_channel (t, t->next_chid))
1683 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
1684 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
1686 chid = t->next_chid;
1687 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
1694 * Send ACK on one or more channels due to buffer in connections.
1696 * @param t Channel which has some free buffer space.
1697 * @param fwd Is this for FWD traffic? (ACK goes to root)
1700 GMT_unchoke_channels (struct MeshTunnel3 *t, int fwd)
1702 struct MeshTChannel *iter;
1703 unsigned int buffer;
1704 unsigned int channels = GMT_count_channels (t);
1705 unsigned int choked_n;
1706 struct MeshChannel *choked[channels];
1708 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
1709 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
1710 if (NULL != t->channel_head)
1711 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
1719 /* Get buffer space */
1720 buffer = GMT_get_buffer (t, fwd);
1726 /* Count and remember choked channels */
1728 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1730 if (GNUNET_NO == GMCH_get_allowed (iter->ch, fwd))
1732 choked[choked_n++] = iter->ch;
1736 /* Unchoke random channels */
1737 while (0 < buffer && 0 < choked_n)
1739 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1741 GMCH_allow_client (choked[r], fwd);
1744 choked[r] = choked[choked_n];
1750 * Send ACK on one or more connections due to buffer space to the client.
1752 * Iterates all connections of the tunnel and sends ACKs appropriately.
1755 * @param fwd Is this in for FWD traffic? (ACK goes dest->root)
1758 GMT_send_acks (struct MeshTunnel3 *t, int fwd)
1760 struct MeshTConnection *iter;
1763 uint32_t allow_per_connection;
1765 unsigned int buffer;
1767 LOG (GNUNET_ERROR_TYPE_DEBUG,
1768 "Tunnel send %s ACKs on %s\n",
1769 fwd ? "FWD" : "BCK", GMT_2s (t));
1776 if (NULL == t->channel_head ||
1777 GNUNET_NO == GMCH_is_origin (t->channel_head->ch, !fwd))
1783 buffer = GMT_get_buffer (t, fwd);
1785 /* Count connections, how many messages are already allowed */
1786 cs = GMT_count_connections (t);
1787 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
1789 allowed += GMC_get_allowed (iter->c, fwd);
1792 /* Make sure there is no overflow */
1793 if (allowed > buffer)
1799 /* Authorize connections to send more data */
1800 to_allow = buffer; /* - allowed; */
1802 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
1804 allow_per_connection = to_allow/cs;
1805 to_allow -= allow_per_connection;
1807 if (GMC_get_allowed (iter->c, fwd) > 64 / 3)
1811 GMC_allow (iter->c, buffer, fwd);
1814 GNUNET_break (to_allow == 0);
1819 * Sends an already built message on a tunnel, encrypting it and
1820 * choosing the best connection.
1822 * @param message Message to send. Function modifies it.
1823 * @param t Tunnel on which this message is transmitted.
1824 * @param ch Channel on which this message is transmitted.
1825 * @param fwd Is this a fwd message on @c ch?
1828 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
1829 struct MeshTunnel3 *t,
1830 struct MeshChannel *ch,
1833 struct MeshConnection *c;
1834 struct GNUNET_MESH_Encrypted *msg;
1835 size_t size = ntohs (message->size);
1836 size_t encrypted_size;
1837 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
1841 if (MESH_TUNNEL3_READY != t->state)
1843 queue_data (t, ch, message);
1846 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
1848 if (myid == GMP_get_short_id (t->peer))
1850 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
1851 handle_decrypted (t, message, fwd);
1855 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
1856 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
1857 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
1859 encrypted_size = t_encrypt (t, &msg[1], message, size, iv);
1860 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + encrypted_size);
1861 c = tunnel_get_connection (t);
1864 GNUNET_break (GNUNET_YES == t->destroy);
1867 type = ntohs (message->type);
1870 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1871 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1872 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1873 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1874 msg->cid = *GMC_get_id (c);
1875 msg->ttl = htonl (default_ttl);
1878 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
1879 GNUNET_MESH_DEBUG_M2S (type));
1883 fwd = GMC_is_origin (c, GNUNET_YES);
1884 GMC_send_prebuilt_message (&msg->header, c, fwd);
1888 * Is the tunnel directed towards the local peer?
1892 * @return #GNUNET_YES if it is loopback.
1895 GMT_is_loopback (const struct MeshTunnel3 *t)
1897 return (myid == GMP_get_short_id(t->peer));
1902 * Is the tunnel using this path already?
1907 * @return #GNUNET_YES a connection uses this path.
1910 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
1912 struct MeshTConnection *iter;
1914 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1915 if (GMC_get_path (iter->c) == p)
1923 * Get a cost of a path for a tunnel considering existing connections.
1926 * @param path Candidate path.
1928 * @return Cost of the path (path length + number of overlapping nodes)
1931 GMT_get_path_cost (const struct MeshTunnel3 *t,
1932 const struct MeshPeerPath *path)
1934 struct MeshTConnection *iter;
1935 unsigned int overlap;
1943 GNUNET_assert (NULL != t);
1945 for (i = 0; i < path->length; i++)
1947 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1949 for (j = 0; j < GMC_get_path (iter->c)->length; j++)
1951 if (path->peers[i] == GMC_get_path (iter->c)->peers[j])
1959 return (path->length + overlap) * (path->score * -1);
1964 * Get the static string for the peer this tunnel is directed.
1968 * @return Static string the destination peer's ID.
1971 GMT_2s (const struct MeshTunnel3 *t)
1973 return GMP_2s (t->peer);