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.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, 5)
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 connectivity.
87 enum MeshTunnel3CState cstate;
90 * State of the tunnel encryption.
92 enum MeshTunnel3EState estate;
95 * Key eXchange context.
97 struct MeshTunnelKXCtx *kx_ctx;
100 * Encryption ("our") key.
102 struct GNUNET_CRYPTO_SymmetricSessionKey e_key;
105 * Decryption ("their") key.
107 struct GNUNET_CRYPTO_SymmetricSessionKey d_key;
110 * Task to start the rekey process.
112 GNUNET_SCHEDULER_TaskIdentifier rekey_task;
115 * Paths that are actively used to reach the destination peer.
117 struct MeshTConnection *connection_head;
118 struct MeshTConnection *connection_tail;
121 * Next connection number.
126 * Channels inside this tunnel.
128 struct MeshTChannel *channel_head;
129 struct MeshTChannel *channel_tail;
132 * Channel ID for the next created channel.
134 MESH_ChannelNumber next_chid;
137 * Destroy flag: if true, destroy on last message.
142 * Queued messages, to transmit once tunnel gets connected.
144 struct MeshTunnelDelayed *tq_head;
145 struct MeshTunnelDelayed *tq_tail;
150 * Struct used to save messages in a non-ready tunnel to send once connected.
152 struct MeshTunnelDelayed
157 struct MeshTunnelDelayed *next;
158 struct MeshTunnelDelayed *prev;
163 struct MeshTunnel3 *t;
168 struct MeshChannel *ch;
173 /* struct GNUNET_MessageHeader *msg; */
178 * Handle for messages queued but not yet sent.
180 struct MeshTunnel3Queue
183 * Connection queue handle, to cancel if necessary.
185 struct MeshConnectionQueue *q;
188 * Handle in case message hasn't been given to a connection yet.
190 struct MeshTunnelDelayed *tq;
193 * Continuation to call once sent.
198 * Closure for @c cont.
204 /******************************************************************************/
205 /******************************* GLOBALS ***********************************/
206 /******************************************************************************/
209 * Global handle to the statistics service.
211 extern struct GNUNET_STATISTICS_Handle *stats;
214 * Local peer own ID (memory efficient handle).
216 extern GNUNET_PEER_Id myid;
219 * Local peer own ID (full value).
221 extern struct GNUNET_PeerIdentity my_full_id;
225 * Set of all tunnels, in order to trigger a new exchange on rekey.
226 * Indexed by peer's ID.
228 static struct GNUNET_CONTAINER_MultiPeerMap *tunnels;
231 * Default TTL for payload packets.
233 static unsigned long long default_ttl;
238 const static struct GNUNET_CRYPTO_EddsaPrivateKey *my_private_key;
241 * Own ephemeral private key.
243 static struct GNUNET_CRYPTO_EcdhePrivateKey *my_ephemeral_key;
246 * Cached message used to perform a key exchange.
248 static struct GNUNET_MESH_KX_Ephemeral kx_msg;
251 * Task to generate a new ephemeral key.
253 static GNUNET_SCHEDULER_TaskIdentifier rekey_task;
258 static struct GNUNET_TIME_Relative rekey_period;
260 /******************************************************************************/
261 /******************************** STATIC ***********************************/
262 /******************************************************************************/
265 * Get string description for tunnel connectivity state.
267 * @param cs Tunnel state.
269 * @return String representation.
272 cstate2s (enum MeshTunnel3CState cs)
274 static char buf[128];
278 case MESH_TUNNEL3_NEW:
279 return "MESH_TUNNEL3_NEW";
280 case MESH_TUNNEL3_SEARCHING:
281 return "MESH_TUNNEL3_SEARCHING";
282 case MESH_TUNNEL3_WAITING:
283 return "MESH_TUNNEL3_WAITING";
284 case MESH_TUNNEL3_READY:
285 return "MESH_TUNNEL3_READY";
288 sprintf (buf, "%u (UNKNOWN STATE)", cs);
296 * Get string description for tunnel encryption state.
298 * @param es Tunnel state.
300 * @return String representation.
303 estate2s (enum MeshTunnel3EState es)
305 static char buf[128];
309 case MESH_TUNNEL3_KEY_UNINITIALIZED:
310 return "MESH_TUNNEL3_KEY_UNINITIALIZED";
311 case MESH_TUNNEL3_KEY_SENT:
312 return "MESH_TUNNEL3_KEY_SENT";
313 case MESH_TUNNEL3_KEY_PING:
314 return "MESH_TUNNEL3_KEY_PING";
315 case MESH_TUNNEL3_KEY_OK:
316 return "MESH_TUNNEL3_KEY_OK";
319 sprintf (buf, "%u (UNKNOWN STATE)", es);
327 * @brief Check if tunnel is ready to send traffic.
329 * Tunnel must be connected and with encryption correctly set up.
331 * @param t Tunnel to check.
333 * @return #GNUNET_YES if ready, #GNUNET_NO otherwise
336 is_ready (struct MeshTunnel3 *t)
338 return (MESH_TUNNEL3_READY == t->cstate
339 && MESH_TUNNEL3_KEY_OK == t->estate)
340 || GMT_is_loopback (t);
345 * Ephemeral key message purpose size.
347 * @return Size of the part of the ephemeral key message that must be signed.
350 ephemeral_purpose_size (void)
352 return sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
353 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
354 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
355 sizeof (struct GNUNET_CRYPTO_EcdhePublicKey) +
356 sizeof (struct GNUNET_PeerIdentity);
361 * Size of the encrypted part of a ping message.
363 * @return Size of the encrypted part of a ping message.
366 ping_encryption_size (void)
368 return sizeof (struct GNUNET_PeerIdentity) + sizeof (uint32_t);
373 * Get the channel's buffer. ONLY FOR NON-LOOPBACK CHANNELS!!
375 * @param tch Tunnel's channel handle.
377 * @return Amount of messages the channel can still buffer towards the client.
380 get_channel_buffer (const struct MeshTChannel *tch)
384 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
385 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
387 return GMCH_get_buffer (tch->ch, fwd);
392 * Get the channel's allowance status.
394 * @param tch Tunnel's channel handle.
396 * @return #GNUNET_YES if we allowed the client to send data to us.
399 get_channel_allowed (const struct MeshTChannel *tch)
403 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
404 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
406 return GMCH_get_allowed (tch->ch, fwd);
411 * Get the connection's buffer.
413 * @param tc Tunnel's connection handle.
415 * @return Amount of messages the connection can still buffer.
418 get_connection_buffer (const struct MeshTConnection *tc)
422 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
423 fwd = GMC_is_origin (tc->c, GNUNET_YES);
425 return GMC_get_buffer (tc->c, fwd);
430 * Get the connection's allowance.
432 * @param tc Tunnel's connection handle.
434 * @return Amount of messages we have allowed the next peer to send us.
437 get_connection_allowed (const struct MeshTConnection *tc)
441 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
442 fwd = GMC_is_origin (tc->c, GNUNET_YES);
444 return GMC_get_allowed (tc->c, fwd);
449 * Check that a ephemeral key message s well formed and correctly signed.
451 * @param t Tunnel on which the message came.
452 * @param msg The ephemeral key message.
454 * @return GNUNET_OK if message is fine, GNUNET_SYSERR otherwise.
457 check_ephemeral (struct MeshTunnel3 *t,
458 const struct GNUNET_MESH_KX_Ephemeral *msg)
460 /* Check message size */
461 if (ntohs (msg->header.size) != sizeof (struct GNUNET_MESH_KX_Ephemeral))
462 return GNUNET_SYSERR;
464 /* Check signature size */
465 if (ntohl (msg->purpose.size) != ephemeral_purpose_size ())
466 return GNUNET_SYSERR;
469 if (0 != memcmp (&msg->origin_identity,
470 GMP_get_id (t->peer),
471 sizeof (struct GNUNET_PeerIdentity)))
472 return GNUNET_SYSERR;
474 /* Check signature */
476 GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_MESH_KX,
479 &msg->origin_identity.public_key))
480 return GNUNET_SYSERR;
487 * Encrypt data with the tunnel key.
489 * @param t Tunnel whose key to use.
490 * @param dst Destination for the encrypted data.
491 * @param src Source of the plaintext. Can overlap with @c dst.
492 * @param size Size of the plaintext.
493 * @param iv Initialization Vector to use.
496 t_encrypt (struct MeshTunnel3 *t,
497 void *dst, const void *src,
498 size_t size, uint32_t iv)
500 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
502 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->e_key, &iv, sizeof (uint32_t), NULL);
503 return GNUNET_CRYPTO_symmetric_encrypt (src, size, &t->e_key, &siv, dst);
508 * Decrypt data with the tunnel key.
510 * @param t Tunnel whose key to use.
511 * @param dst Destination for the plaintext.
512 * @param src Source of the encrypted data. Can overlap with @c dst.
513 * @param size Size of the encrypted data.
514 * @param iv Initialization Vector to use.
517 t_decrypt (struct MeshTunnel3 *t,
518 void *dst, const void *src,
519 size_t size, uint32_t iv)
521 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
523 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->d_key, &iv, sizeof (uint32_t), NULL);
524 return GNUNET_CRYPTO_symmetric_decrypt (src, size, &t->d_key, &siv, dst);
529 * Create key material by doing ECDH on the local and remote ephemeral keys.
531 * @param key_material Where to store the key material.
532 * @param ephemeral_key Peer's public ephemeral key.
535 derive_key_material (struct GNUNET_HashCode *key_material,
536 const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key)
539 GNUNET_CRYPTO_ecc_ecdh (my_ephemeral_key,
548 * Create a symmetic key from the identities of both ends and the key material
551 * @param key Destination for the generated key.
552 * @param sender ID of the peer that will encrypt with @c key.
553 * @param receiver ID of the peer that will decrypt with @c key.
554 * @param key_material Hash created with ECDH with the ephemeral keys.
557 derive_symmertic (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
558 const struct GNUNET_PeerIdentity *sender,
559 const struct GNUNET_PeerIdentity *receiver,
560 const struct GNUNET_HashCode *key_material)
562 const char salt[] = "MESH kx salt";
564 GNUNET_CRYPTO_kdf (key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
566 key_material, sizeof (struct GNUNET_HashCode),
567 sender, sizeof (struct GNUNET_PeerIdentity),
568 receiver, sizeof (struct GNUNET_PeerIdentity),
573 * Pick a connection on which send the next data message.
575 * @param t Tunnel on which to send the message.
577 * @return The connection on which to send the next message.
579 static struct MeshConnection *
580 tunnel_get_connection (struct MeshTunnel3 *t)
582 struct MeshTConnection *iter;
583 struct MeshConnection *best;
585 unsigned int lowest_q;
587 LOG (GNUNET_ERROR_TYPE_DEBUG, "tunnel_get_connection %s\n", GMP_2s (t->peer));
590 for (iter = t->connection_head; NULL != iter; iter = iter->next)
592 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s: %u\n",
593 GMC_2s (iter->c), GMC_get_state (iter->c));
594 if (MESH_CONNECTION_READY == GMC_get_state (iter->c))
596 qn = GMC_get_qn (iter->c, GMC_is_origin (iter->c, GNUNET_YES));
597 LOG (GNUNET_ERROR_TYPE_DEBUG, " q_n %u, \n", qn);
605 LOG (GNUNET_ERROR_TYPE_DEBUG, " selected: connection %s\n", GMC_2s (best));
612 * Delete a queued message: most probably channel was destroyed before the
613 * tunnel's key exchange had a chance to finish.
615 * @param tq Queue handle.
618 unqueue_data (struct MeshTunnelDelayed *tq)
620 GNUNET_CONTAINER_DLL_remove (tq->t->tq_head, tq->t->tq_tail, tq);
626 * Send all cached messages that we can, tunnel is online.
628 * @param t Tunnel that holds the messages. Cannot be loopback.
631 send_queued_data (struct MeshTunnel3 *t)
633 struct MeshTunnelDelayed *tq;
634 struct MeshTunnelDelayed *next;
637 LOG (GNUNET_ERROR_TYPE_DEBUG,
638 "GMT_send_queued_data on tunnel %s\n",
641 if (GMT_is_loopback (t))
647 if (GNUNET_NO == is_ready (t))
649 LOG (GNUNET_ERROR_TYPE_DEBUG, " not ready yet: %s/%s\n",
650 estate2s (t->estate), cstate2s (t->cstate));
654 room = GMT_get_connections_buffer (t);
655 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
656 LOG (GNUNET_ERROR_TYPE_DEBUG, " tq head: %p\n", t->tq_head);
657 for (tq = t->tq_head; NULL != tq && room > 0; tq = next)
659 LOG (GNUNET_ERROR_TYPE_DEBUG, " data on channel %s\n", GMCH_2s (tq->ch));
662 GMCH_send_prebuilt_message ((struct GNUNET_MessageHeader *) &tq[1],
663 tq->ch, GMCH_is_origin (tq->ch, GNUNET_YES),
667 LOG (GNUNET_ERROR_TYPE_DEBUG,
668 "GMT_send_queued_data end\n",
674 * Cache a message to be sent once tunnel is online.
676 * @param t Tunnel to hold the message.
677 * @param ch Channel the message is about.
678 * @param msg Message itself (copy will be made).
680 static struct MeshTunnelDelayed *
681 queue_data (struct MeshTunnel3 *t,
682 struct MeshChannel *ch,
683 const struct GNUNET_MessageHeader *msg)
685 struct MeshTunnelDelayed *tq;
686 uint16_t size = ntohs (msg->size);
688 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue data on Tunnel %s\n", GMT_2s (t));
690 if (GNUNET_YES == is_ready (t))
696 tq = GNUNET_malloc (sizeof (struct MeshTunnelDelayed) + size);
700 memcpy (&tq[1], msg, size);
701 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tq);
708 * Sends key exchange message on a tunnel, choosing the best connection.
709 * Should not be called on loopback tunnels.
711 * @param t Tunnel on which this message is transmitted.
712 * @param message Message to send. Function modifies it.
715 send_kx (struct MeshTunnel3 *t,
716 const struct GNUNET_MessageHeader *message)
718 struct MeshConnection *c;
719 struct GNUNET_MESH_KX *msg;
720 size_t size = ntohs (message->size);
721 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
725 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
727 /* Avoid loopback. */
728 if (GMT_is_loopback (t))
730 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
735 /* Must have a connection. */
736 if (NULL == t->connection_head)
742 msg = (struct GNUNET_MESH_KX *) cbuf;
743 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
744 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
745 c = tunnel_get_connection (t);
748 GNUNET_break (GNUNET_YES == t->destroy);
751 type = ntohs (message->type);
754 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
755 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
756 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
757 msg->reserved = htonl (0);
758 memcpy (&msg[1], message, size);
761 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
766 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
767 /* TODO save handle and cancel in case of a unneeded retransmission */
768 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
773 * Send the ephemeral key on a tunnel.
775 * @param t Tunnel on which to send the key.
778 send_ephemeral (struct MeshTunnel3 *t)
780 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
782 kx_msg.sender_status = htonl (t->estate);
783 send_kx (t, &kx_msg.header);
787 * Send a ping message on a tunnel.
789 * @param t Tunnel on which to send the ping.
792 send_ping (struct MeshTunnel3 *t)
794 struct GNUNET_MESH_KX_Ping msg;
796 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
797 msg.header.size = htons (sizeof (msg));
798 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
799 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
800 msg.target = *GMP_get_id (t->peer);
801 msg.nonce = t->kx_ctx->challenge;
803 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
804 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&msg.target));
805 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
806 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
807 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg.target));
809 send_kx (t, &msg.header);
814 * Send a pong message on a tunnel.
816 * @param t Tunnel on which to send the pong.
817 * @param challenge Value sent in the ping that we have to send back.
820 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
822 struct GNUNET_MESH_KX_Pong msg;
824 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
825 msg.header.size = htons (sizeof (msg));
826 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
827 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
828 msg.nonce = challenge;
829 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
830 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
831 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
833 send_kx (t, &msg.header);
838 * Initiate a rekey with the remote peer.
840 * @param cls Closure (tunnel).
841 * @param tc TaskContext.
844 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
846 struct MeshTunnel3 *t = cls;
848 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
850 LOG (GNUNET_ERROR_TYPE_DEBUG, "Re-key Tunnel\n");
851 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
854 if (NULL == t->kx_ctx)
856 LOG (GNUNET_ERROR_TYPE_DEBUG, " new kx ctx\n");
857 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
858 t->kx_ctx->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
860 t->kx_ctx->d_key_old = t->d_key;
865 case MESH_TUNNEL3_KEY_UNINITIALIZED:
866 t->estate = MESH_TUNNEL3_KEY_SENT;
868 case MESH_TUNNEL3_KEY_SENT:
870 case MESH_TUNNEL3_KEY_PING:
871 case MESH_TUNNEL3_KEY_OK:
873 t->estate = MESH_TUNNEL3_KEY_PING;
876 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->estate);
879 LOG (GNUNET_ERROR_TYPE_DEBUG, " next call in %s\n",
880 GNUNET_STRINGS_relative_time_to_string (REKEY_WAIT, GNUNET_YES));
881 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
886 * Out ephemeral key has changed, create new session key on all tunnels.
888 * @param cls Closure (size of the hashmap).
889 * @param key Current public key.
890 * @param value Value in the hash map (tunnel).
892 * @return #GNUNET_YES, so we should continue to iterate,
895 rekey_iterator (void *cls,
896 const struct GNUNET_PeerIdentity *key,
899 struct MeshTunnel3 *t = value;
900 struct GNUNET_TIME_Relative delay;
904 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
907 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
908 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
909 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
916 * Create a new ephemeral key and key message, schedule next rekeying.
918 * @param cls Closure (unused).
919 * @param tc TaskContext.
922 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
924 struct GNUNET_TIME_Absolute time;
927 rekey_task = GNUNET_SCHEDULER_NO_TASK;
929 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
932 GNUNET_free_non_null (my_ephemeral_key);
933 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
935 time = GNUNET_TIME_absolute_get ();
936 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
937 time = GNUNET_TIME_absolute_add (time, rekey_period);
938 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
939 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
940 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
942 GNUNET_assert (GNUNET_OK ==
943 GNUNET_CRYPTO_eddsa_sign (my_private_key,
947 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
948 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
950 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
955 * Called only on shutdown, destroy every tunnel.
957 * @param cls Closure (unused).
958 * @param key Current public key.
959 * @param value Value in the hash map (tunnel).
961 * @return #GNUNET_YES, so we should continue to iterate,
964 destroy_iterator (void *cls,
965 const struct GNUNET_PeerIdentity *key,
968 struct MeshTunnel3 *t = value;
976 * Demultiplex data per channel and call appropriate channel handler.
978 * @param t Tunnel on which the data came.
979 * @param msg Data message.
980 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
981 * #GNUNET_YES if message is FWD on the respective channel (loopback)
982 * #GNUNET_NO if message is BCK on the respective channel (loopback)
983 * #GNUNET_SYSERR if message on a one-ended channel (remote)
986 handle_data (struct MeshTunnel3 *t,
987 const struct GNUNET_MESH_Data *msg,
990 struct MeshChannel *ch;
994 size = ntohs (msg->header.size);
996 sizeof (struct GNUNET_MESH_Data) +
997 sizeof (struct GNUNET_MessageHeader))
1002 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
1003 GM_m2s (ntohs (msg[1].header.type)));
1006 ch = GMT_get_channel (t, ntohl (msg->chid));
1009 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
1011 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1016 GMCH_handle_data (ch, msg, fwd);
1021 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
1023 * @param t Tunnel on which the DATA ACK came.
1024 * @param msg DATA ACK message.
1025 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1026 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1027 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1028 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1031 handle_data_ack (struct MeshTunnel3 *t,
1032 const struct GNUNET_MESH_DataACK *msg,
1035 struct MeshChannel *ch;
1039 size = ntohs (msg->header.size);
1040 if (size != sizeof (struct GNUNET_MESH_DataACK))
1047 ch = GMT_get_channel (t, ntohl (msg->chid));
1050 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
1052 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1057 GMCH_handle_data_ack (ch, msg, fwd);
1062 * Handle channel create.
1064 * @param t Tunnel on which the data came.
1065 * @param msg Data message.
1068 handle_ch_create (struct MeshTunnel3 *t,
1069 const struct GNUNET_MESH_ChannelCreate *msg)
1071 struct MeshChannel *ch;
1075 size = ntohs (msg->header.size);
1076 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
1083 ch = GMT_get_channel (t, ntohl (msg->chid));
1084 if (NULL != ch && ! GMT_is_loopback (t))
1086 /* Probably a retransmission, safe to ignore */
1087 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
1091 ch = GMCH_handle_create (t, msg);
1094 GMT_add_channel (t, ch);
1100 * Handle channel NACK: check correctness and call channel handler for NACKs.
1102 * @param t Tunnel on which the NACK came.
1103 * @param msg NACK message.
1106 handle_ch_nack (struct MeshTunnel3 *t,
1107 const struct GNUNET_MESH_ChannelManage *msg)
1109 struct MeshChannel *ch;
1113 size = ntohs (msg->header.size);
1114 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1121 ch = GMT_get_channel (t, ntohl (msg->chid));
1124 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
1126 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1131 GMCH_handle_nack (ch);
1136 * Handle a CHANNEL ACK (SYNACK/ACK).
1138 * @param t Tunnel on which the CHANNEL ACK came.
1139 * @param msg CHANNEL ACK message.
1140 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1141 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1142 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1143 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1146 handle_ch_ack (struct MeshTunnel3 *t,
1147 const struct GNUNET_MESH_ChannelManage *msg,
1150 struct MeshChannel *ch;
1154 size = ntohs (msg->header.size);
1155 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1162 ch = GMT_get_channel (t, ntohl (msg->chid));
1165 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1167 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1172 GMCH_handle_ack (ch, msg, fwd);
1178 * Handle a channel destruction message.
1180 * @param t Tunnel on which the message came.
1181 * @param msg Channel destroy message.
1182 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1183 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1184 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1185 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1188 handle_ch_destroy (struct MeshTunnel3 *t,
1189 const struct GNUNET_MESH_ChannelManage *msg,
1192 struct MeshChannel *ch;
1196 size = ntohs (msg->header.size);
1197 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1204 ch = GMT_get_channel (t, ntohl (msg->chid));
1207 /* Probably a retransmission, safe to ignore */
1211 GMCH_handle_destroy (ch, msg, fwd);
1216 * The peer's ephemeral key has changed: update the symmetrical keys.
1218 * @param t Tunnel this message came on.
1219 * @param msg Key eXchange message.
1222 handle_ephemeral (struct MeshTunnel3 *t,
1223 const struct GNUNET_MESH_KX_Ephemeral *msg)
1225 struct GNUNET_HashCode km;
1226 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1228 if (GNUNET_OK != check_ephemeral (t, msg))
1230 GNUNET_break_op (0);
1233 derive_key_material (&km, &msg->ephemeral_key);
1234 LOG (GNUNET_ERROR_TYPE_DEBUG, " km is %s\n", GNUNET_h2s (&km));
1235 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1236 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1237 if (MESH_TUNNEL3_KEY_SENT == t->estate)
1239 LOG (GNUNET_ERROR_TYPE_DEBUG, " our key was sent, send ping\n");
1241 t->estate = MESH_TUNNEL3_KEY_PING;
1247 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1248 * Answer with by retransmitting the challenge with the "opposite" key.
1250 * @param t Tunnel this message came on.
1251 * @param msg Key eXchange Ping message.
1254 handle_ping (struct MeshTunnel3 *t,
1255 const struct GNUNET_MESH_KX_Ping *msg)
1257 struct GNUNET_MESH_KX_Ping res;
1259 if (ntohs (msg->header.size) != sizeof (res))
1261 GNUNET_break_op (0);
1265 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1266 t_decrypt (t, &res.target, &msg->target, ping_encryption_size (), msg->iv);
1267 if (0 != memcmp (&my_full_id, &res.target, sizeof (my_full_id)))
1269 GNUNET_break_op (0);
1270 LOG (GNUNET_ERROR_TYPE_DEBUG, " e got %u\n", msg->nonce);
1271 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg->target));
1272 LOG (GNUNET_ERROR_TYPE_DEBUG, " got %u\n", res.nonce);
1273 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&res.target));
1277 send_pong (t, res.nonce);
1282 * Peer has answer to our challenge.
1283 * If answer is successful, consider the key exchange finished and clean
1284 * up all related state.
1286 * @param t Tunnel this message came on.
1287 * @param msg Key eXchange Pong message.
1290 handle_pong (struct MeshTunnel3 *t,
1291 const struct GNUNET_MESH_KX_Pong *msg)
1295 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1296 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1298 GNUNET_break_op (0);
1301 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1303 if (challenge != t->kx_ctx->challenge)
1305 LOG (GNUNET_ERROR_TYPE_DEBUG,
1306 "Wrong PONG challenge: %u (e: %u). Expected: %u.\n",
1307 challenge, msg->nonce, t->kx_ctx->challenge);
1308 GNUNET_break_op (0);
1311 GNUNET_SCHEDULER_cancel (t->rekey_task);
1312 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1313 GNUNET_free (t->kx_ctx);
1315 GMT_change_estate (t, MESH_TUNNEL3_KEY_OK);
1320 * Demultiplex by message type and call appropriate handler for a message
1321 * towards a channel of a local tunnel.
1323 * @param t Tunnel this message came on.
1324 * @param msgh Message header.
1325 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1326 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1327 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1328 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1331 handle_decrypted (struct MeshTunnel3 *t,
1332 const struct GNUNET_MessageHeader *msgh,
1337 type = ntohs (msgh->type);
1338 LOG (GNUNET_ERROR_TYPE_DEBUG,
1339 "Got a %s message!\n",
1344 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1345 /* Don't send hop ACK, wait for client to ACK */
1346 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1349 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1350 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1353 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1354 handle_ch_create (t,
1355 (struct GNUNET_MESH_ChannelCreate *) msgh);
1358 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1360 (struct GNUNET_MESH_ChannelManage *) msgh);
1363 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1365 (struct GNUNET_MESH_ChannelManage *) msgh,
1369 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1370 handle_ch_destroy (t,
1371 (struct GNUNET_MESH_ChannelManage *) msgh,
1376 GNUNET_break_op (0);
1377 LOG (GNUNET_ERROR_TYPE_DEBUG,
1378 "end-to-end message not known (%u)\n",
1379 ntohs (msgh->type));
1383 /******************************************************************************/
1384 /******************************** API ***********************************/
1385 /******************************************************************************/
1388 * Decrypt and demultiplex by message type. Call appropriate handler
1389 * for every message.
1391 * @param t Tunnel this message came on.
1392 * @param msg Encrypted message.
1395 GMT_handle_encrypted (struct MeshTunnel3 *t,
1396 const struct GNUNET_MESH_Encrypted *msg)
1398 size_t size = ntohs (msg->header.size);
1399 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1400 size_t decrypted_size;
1401 char cbuf [payload_size];
1402 struct GNUNET_MessageHeader *msgh;
1405 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1407 while (off < decrypted_size)
1409 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1410 handle_decrypted (t, msgh, GNUNET_SYSERR);
1411 off += ntohs (msgh->size);
1417 * Demultiplex an encapsulated KX message by message type.
1419 * @param t Tunnel on which the message came.
1420 * @param message Payload of KX message.
1423 GMT_handle_kx (struct MeshTunnel3 *t,
1424 const struct GNUNET_MessageHeader *message)
1428 type = ntohs (message->type);
1429 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1432 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1433 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1436 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1437 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1440 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1441 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1445 GNUNET_break_op (0);
1446 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1452 * Initialize the tunnel subsystem.
1454 * @param c Configuration handle.
1455 * @param key ECC private key, to derive all other keys and do crypto.
1458 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1459 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1461 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1463 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1466 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1467 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1471 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1474 rekey_period = GNUNET_TIME_UNIT_DAYS;
1477 my_private_key = key;
1478 kx_msg.header.size = htons (sizeof (kx_msg));
1479 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1480 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1481 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1482 kx_msg.origin_identity = my_full_id;
1483 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1485 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1490 * Shut down the tunnel subsystem.
1495 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1497 GNUNET_SCHEDULER_cancel (rekey_task);
1498 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1500 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &destroy_iterator, NULL);
1501 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1508 * @param destination Peer this tunnel is towards.
1510 struct MeshTunnel3 *
1511 GMT_new (struct MeshPeer *destination)
1513 struct MeshTunnel3 *t;
1515 t = GNUNET_new (struct MeshTunnel3);
1517 t->peer = destination;
1520 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1521 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1532 * Change the tunnel's connection state.
1534 * @param t Tunnel whose connection state to change.
1535 * @param cstate New connection state.
1538 GMT_change_cstate (struct MeshTunnel3* t, enum MeshTunnel3CState cstate)
1542 LOG (GNUNET_ERROR_TYPE_DEBUG,
1543 "Tunnel %s cstate was %s\n",
1544 GMP_2s (t->peer), cstate2s (t->cstate));
1545 LOG (GNUNET_ERROR_TYPE_DEBUG,
1546 "Tunnel %s cstate is now %s\n",
1547 GMP_2s (t->peer), cstate2s (cstate));
1548 if (myid != GMP_get_short_id (t->peer) &&
1549 MESH_TUNNEL3_READY != t->cstate &&
1550 MESH_TUNNEL3_READY == cstate)
1553 if (MESH_TUNNEL3_KEY_OK == t->estate)
1555 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered send queued data\n");
1556 send_queued_data (t);
1558 else if (MESH_TUNNEL3_KEY_UNINITIALIZED == t->estate)
1560 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1561 rekey_tunnel (t, NULL);
1566 if (MESH_TUNNEL3_READY == cstate && 3 <= GMT_count_connections (t))
1568 GMP_stop_search (t->peer);
1573 * Change the tunnel encryption state.
1575 * @param t Tunnel whose encryption state to change.
1576 * @param state New encryption state.
1579 GMT_change_estate (struct MeshTunnel3* t, enum MeshTunnel3EState state)
1583 LOG (GNUNET_ERROR_TYPE_DEBUG,
1584 "Tunnel %s estate was %s\n",
1585 GMP_2s (t->peer), estate2s (t->estate));
1586 LOG (GNUNET_ERROR_TYPE_DEBUG,
1587 "Tunnel %s estate is now %s\n",
1588 GMP_2s (t->peer), estate2s (state));
1589 if (myid != GMP_get_short_id (t->peer) &&
1590 MESH_TUNNEL3_KEY_OK != t->estate && MESH_TUNNEL3_KEY_OK == state)
1593 send_queued_data (t);
1601 * Add a connection to a tunnel.
1604 * @param c Connection.
1607 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1609 struct MeshTConnection *aux;
1611 GNUNET_assert (NULL != c);
1613 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1617 aux = GNUNET_new (struct MeshTConnection);
1619 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1624 * Remove a connection from a tunnel.
1627 * @param c Connection.
1630 GMT_remove_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1632 struct MeshTConnection *aux;
1634 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1637 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1645 * Add a channel to a tunnel.
1648 * @param ch Channel.
1651 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1653 struct MeshTChannel *aux;
1655 GNUNET_assert (NULL != ch);
1657 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1659 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1661 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1666 aux = GNUNET_new (struct MeshTChannel);
1668 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1669 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1671 if (GNUNET_YES == t->destroy)
1673 t->destroy = GNUNET_NO;
1674 LOG (GNUNET_ERROR_TYPE_DEBUG, " undo destroy!\n");
1680 * Remove a channel from a tunnel.
1683 * @param ch Channel.
1686 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1688 struct MeshTChannel *aux;
1690 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1691 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1695 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1696 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1705 * Search for a channel by global ID.
1707 * @param t Tunnel containing the channel.
1708 * @param chid Public channel number.
1710 * @return channel handler, NULL if doesn't exist
1712 struct MeshChannel *
1713 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1715 struct MeshTChannel *iter;
1720 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1722 if (GMCH_get_id (iter->ch) == chid)
1726 return NULL == iter ? NULL : iter->ch;
1731 * Tunnel is empty: destroy it.
1733 * Notifies all connections about the destruction.
1735 * @param t Tunnel to destroy.
1738 GMT_destroy_empty (struct MeshTunnel3 *t)
1740 struct MeshTConnection *iter;
1742 LOG (GNUNET_ERROR_TYPE_DEBUG, "Tunnel empty: destroying scheduled\n");
1743 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1745 GMC_send_destroy (iter->c);
1748 t->cstate = MESH_TUNNEL3_NEW;
1749 t->destroy = GNUNET_YES;
1754 * Destroy tunnel if empty (no more channels).
1756 * @param t Tunnel to destroy if empty.
1759 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1761 if (1 < GMT_count_channels (t))
1764 GMT_destroy_empty (t);
1769 * Destroy the tunnel.
1771 * This function does not generate any warning traffic to clients or peers.
1774 * Cancel messages belonging to this tunnel queued to neighbors.
1775 * Free any allocated resources linked to the tunnel.
1777 * @param t The tunnel to destroy.
1780 GMT_destroy (struct MeshTunnel3 *t)
1782 struct MeshTConnection *iter_c;
1783 struct MeshTConnection *next_c;
1784 struct MeshTChannel *iter_ch;
1785 struct MeshTChannel *next_ch;
1790 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
1792 GNUNET_break (GNUNET_YES ==
1793 GNUNET_CONTAINER_multipeermap_remove (tunnels,
1794 GMP_get_id (t->peer), t));
1796 for (iter_c = t->connection_head; NULL != iter_c; iter_c = next_c)
1798 next_c = iter_c->next;
1799 GMC_destroy (iter_c->c);
1801 for (iter_ch = t->channel_head; NULL != iter_ch; iter_ch = next_ch)
1803 next_ch = iter_ch->next;
1804 GMCH_destroy (iter_ch->ch);
1805 /* Should only happen on shutdown, but it's ok. */
1808 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
1809 GMP_set_tunnel (t->peer, NULL);
1811 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1812 GNUNET_SCHEDULER_cancel (t->rekey_task);
1819 * @brief Use the given path for the tunnel.
1820 * Update the next and prev hops (and RCs).
1821 * (Re)start the path refresh in case the tunnel is locally owned.
1823 * @param t Tunnel to update.
1824 * @param p Path to use.
1826 * @return Connection created.
1828 struct MeshConnection *
1829 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
1831 struct MeshConnection *c;
1832 struct GNUNET_HashCode cid;
1833 unsigned int own_pos;
1835 if (NULL == t || NULL == p)
1841 for (own_pos = 0; own_pos < p->length; own_pos++)
1843 if (p->peers[own_pos] == myid)
1846 if (own_pos > p->length - 1)
1852 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
1853 c = GMC_new (&cid, t, p, own_pos);
1856 /* Path was flawed */
1859 GMT_add_connection (t, c);
1865 * Count established (ready) connections of a tunnel.
1867 * @param t Tunnel on which to count.
1869 * @return Number of connections.
1872 GMT_count_connections (struct MeshTunnel3 *t)
1874 struct MeshTConnection *iter;
1877 for (count = 0, iter = t->connection_head;
1879 iter = iter->next, count++);
1885 * Count channels of a tunnel.
1887 * @param t Tunnel on which to count.
1889 * @return Number of channels.
1892 GMT_count_channels (struct MeshTunnel3 *t)
1894 struct MeshTChannel *iter;
1897 for (count = 0, iter = t->channel_head;
1899 iter = iter->next, count++) /* skip */;
1906 * Get the connectivity state of a tunnel.
1910 * @return Tunnel's connectivity state.
1912 enum MeshTunnel3CState
1913 GMT_get_cstate (struct MeshTunnel3 *t)
1918 return (enum MeshTunnel3CState) -1;
1925 * Get the maximum buffer space for a tunnel towards a local client.
1929 * @return Biggest buffer space offered by any channel in the tunnel.
1932 GMT_get_channels_buffer (struct MeshTunnel3 *t)
1934 struct MeshTChannel *iter;
1935 unsigned int buffer;
1936 unsigned int ch_buf;
1938 if (NULL == t->channel_head)
1940 /* Probably getting buffer for a channel create/handshake. */
1945 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1947 ch_buf = get_channel_buffer (iter);
1948 if (ch_buf > buffer)
1956 * Get the total buffer space for a tunnel for P2P traffic.
1960 * @return Buffer space offered by all connections in the tunnel.
1963 GMT_get_connections_buffer (struct MeshTunnel3 *t)
1965 struct MeshTConnection *iter;
1966 unsigned int buffer;
1969 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1971 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
1976 buffer += get_connection_buffer (iter);
1984 * Get the tunnel's destination.
1988 * @return ID of the destination peer.
1990 const struct GNUNET_PeerIdentity *
1991 GMT_get_destination (struct MeshTunnel3 *t)
1993 return GMP_get_id (t->peer);
1998 * Get the tunnel's next free global channel ID.
2002 * @return GID of a channel free to use.
2005 GMT_get_next_chid (struct MeshTunnel3 *t)
2007 MESH_ChannelNumber chid;
2008 MESH_ChannelNumber mask;
2011 /* Set bit 30 depending on the ID relationship. Bit 31 is always 0 for GID.
2012 * If our ID is bigger or loopback tunnel, start at 0, bit 30 = 0
2013 * If peer's ID is bigger, start at 0x4... bit 30 = 1
2015 result = GNUNET_CRYPTO_cmp_peer_identity (&my_full_id, GMP_get_id (t->peer));
2021 while (NULL != GMT_get_channel (t, t->next_chid))
2023 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
2024 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2025 t->next_chid |= mask;
2027 chid = t->next_chid;
2028 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2029 t->next_chid |= mask;
2036 * Send ACK on one or more channels due to buffer in connections.
2038 * @param t Channel which has some free buffer space.
2041 GMT_unchoke_channels (struct MeshTunnel3 *t)
2043 struct MeshTChannel *iter;
2044 unsigned int buffer;
2045 unsigned int channels = GMT_count_channels (t);
2046 unsigned int choked_n;
2047 struct MeshChannel *choked[channels];
2049 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
2050 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
2051 if (NULL != t->channel_head)
2052 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
2054 /* Get buffer space */
2055 buffer = GMT_get_connections_buffer (t);
2061 /* Count and remember choked channels */
2063 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2065 if (GNUNET_NO == get_channel_allowed (iter))
2067 choked[choked_n++] = iter->ch;
2071 /* Unchoke random channels */
2072 while (0 < buffer && 0 < choked_n)
2074 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2076 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
2079 choked[r] = choked[choked_n];
2085 * Send ACK on one or more connections due to buffer space to the client.
2087 * Iterates all connections of the tunnel and sends ACKs appropriately.
2092 GMT_send_connection_acks (struct MeshTunnel3 *t)
2094 struct MeshTConnection *iter;
2097 uint32_t allow_per_connection;
2099 unsigned int buffer;
2101 LOG (GNUNET_ERROR_TYPE_DEBUG,
2102 "Tunnel send connection ACKs on %s\n",
2111 buffer = GMT_get_channels_buffer (t);
2113 /* Count connections, how many messages are already allowed */
2114 cs = GMT_count_connections (t);
2115 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
2117 allowed += get_connection_allowed (iter);
2120 /* Make sure there is no overflow */
2121 if (allowed > buffer)
2126 /* Authorize connections to send more data */
2127 to_allow = buffer; /* - allowed; */
2129 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
2131 allow_per_connection = to_allow/cs;
2132 to_allow -= allow_per_connection;
2134 if (get_connection_allowed (iter) > 64 / 3)
2138 GMC_allow (iter->c, buffer, GMC_is_origin (iter->c, GNUNET_YES));
2141 GNUNET_break (to_allow == 0);
2146 * Callback called when a queued message is sent.
2148 * Calculates the average time and connection packet tracking.
2150 * @param cls Closure (TunnelQueue handle).
2151 * @param c Connection this message was on.
2152 * @param q Connection queue handle (unused).
2153 * @param type Type of message sent.
2154 * @param fwd Was this a FWD going message?
2155 * @param size Size of the message.
2158 message_sent (void *cls,
2159 struct MeshConnection *c,
2160 struct MeshConnectionQueue *q,
2161 uint16_t type, int fwd, size_t size)
2163 struct MeshTunnel3Queue *qt = cls;
2165 GNUNET_assert (NULL != qt->cont);
2166 qt->cont (qt->cont_cls, GMC_get_tunnel (c), qt, type, size);
2172 * Cancel a previously sent message while it's in the queue.
2174 * ONLY can be called before the continuation given to the send function
2175 * is called. Once the continuation is called, the message is no longer in the
2178 * @param q Handle to the queue.
2181 GMT_cancel (struct MeshTunnel3Queue *q)
2186 /* message_sent() will be called and free q */
2188 else if (NULL != q->tq)
2190 unqueue_data (q->tq);
2200 * Sends an already built message on a tunnel, encrypting it and
2201 * choosing the best connection.
2203 * @param message Message to send. Function modifies it.
2204 * @param t Tunnel on which this message is transmitted.
2205 * @param ch Channel on which this message is transmitted.
2206 * @param force Force the tunnel to take the message (buffer overfill).
2207 * @param cont Continuation to call once message is really sent.
2208 * @param cont_cls Closure for @c cont.
2210 * @return Handle to cancel message. NULL if @c cont is NULL.
2212 struct MeshTunnel3Queue *
2213 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2214 struct MeshTunnel3 *t, struct MeshChannel *ch,
2216 GMT_sent cont, void *cont_cls)
2218 struct MeshTunnel3Queue *q;
2219 struct MeshConnection *c;
2220 struct GNUNET_MESH_Encrypted *msg;
2221 size_t size = ntohs (message->size);
2222 size_t encrypted_size;
2223 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
2228 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
2230 if (GNUNET_NO == is_ready (t))
2232 q = GNUNET_new (struct MeshTunnel3Queue);
2233 q->tq = queue_data (t, ch, message);
2237 GNUNET_assert (GNUNET_NO == GMT_is_loopback (t));
2239 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
2240 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
2241 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
2243 encrypted_size = t_encrypt (t, &msg[1], message, size, iv);
2244 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + encrypted_size);
2245 c = tunnel_get_connection (t);
2248 GNUNET_break (GNUNET_YES == t->destroy);
2251 type = ntohs (message->type);
2254 case GNUNET_MESSAGE_TYPE_MESH_DATA:
2255 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
2256 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
2257 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
2258 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
2259 msg->cid = *GMC_get_id (c);
2260 msg->ttl = htonl (default_ttl);
2263 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
2268 fwd = GMC_is_origin (c, GNUNET_YES);
2272 (void) GMC_send_prebuilt_message (&msg->header, c, fwd, force, NULL, NULL);
2275 q = GNUNET_new (struct MeshTunnel3Queue); /* FIXME valgrind: leak*/
2276 q->q = GMC_send_prebuilt_message (&msg->header, c, fwd, force,
2279 q->cont_cls = cont_cls;
2285 * Is the tunnel directed towards the local peer?
2289 * @return #GNUNET_YES if it is loopback.
2292 GMT_is_loopback (const struct MeshTunnel3 *t)
2294 return (myid == GMP_get_short_id (t->peer));
2299 * Is the tunnel this path already?
2304 * @return #GNUNET_YES a connection uses this path.
2307 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2309 struct MeshTConnection *iter;
2311 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2312 if (GMC_get_path (iter->c) == p)
2320 * Get a cost of a path for a tunnel considering existing connections.
2323 * @param path Candidate path.
2325 * @return Cost of the path (path length + number of overlapping nodes)
2328 GMT_get_path_cost (const struct MeshTunnel3 *t,
2329 const struct MeshPeerPath *path)
2331 struct MeshTConnection *iter;
2332 const struct MeshPeerPath *aux;
2333 unsigned int overlap;
2341 GNUNET_assert (NULL != t);
2343 for (i = 0; i < path->length; i++)
2345 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2347 aux = GMC_get_path (iter->c);
2351 for (j = 0; j < aux->length; j++)
2353 if (path->peers[i] == aux->peers[j])
2361 return (path->length + overlap) * (path->score * -1);
2366 * Get the static string for the peer this tunnel is directed.
2370 * @return Static string the destination peer's ID.
2373 GMT_2s (const struct MeshTunnel3 *t)
2378 return GMP_2s (t->peer);