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 /* GMCH_send_prebuilt_message will call GMT_cancel on the current
660 * queue handler, therefore free'ing tq before calling GMT_send.
661 * Since the data to send is part of tq, we need to provide a copy,
662 * so the data is not invalidated.
664 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) &tq[1];
665 size_t m_size = ntohs (msg->size);
667 struct GNUNET_MessageHeader *copy = (struct GNUNET_MessageHeader *) cbuf;
669 LOG (GNUNET_ERROR_TYPE_DEBUG, " msg on channel %s\n", GMCH_2s (tq->ch));
672 memcpy (copy, msg, m_size);
673 GMCH_send_prebuilt_message (copy,
674 tq->ch, GMCH_is_origin (tq->ch, GNUNET_YES),
677 LOG (GNUNET_ERROR_TYPE_DEBUG,
678 "GMT_send_queued_data end\n",
684 * Cache a message to be sent once tunnel is online.
686 * @param t Tunnel to hold the message.
687 * @param ch Channel the message is about.
688 * @param msg Message itself (copy will be made).
690 static struct MeshTunnelDelayed *
691 queue_data (struct MeshTunnel3 *t,
692 struct MeshChannel *ch,
693 const struct GNUNET_MessageHeader *msg)
695 struct MeshTunnelDelayed *tq;
696 uint16_t size = ntohs (msg->size);
698 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue data on Tunnel %s\n", GMT_2s (t));
700 if (GNUNET_YES == is_ready (t))
706 tq = GNUNET_malloc (sizeof (struct MeshTunnelDelayed) + size);
710 memcpy (&tq[1], msg, size);
711 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tq);
718 * Sends key exchange message on a tunnel, choosing the best connection.
719 * Should not be called on loopback tunnels.
721 * @param t Tunnel on which this message is transmitted.
722 * @param message Message to send. Function modifies it.
725 send_kx (struct MeshTunnel3 *t,
726 const struct GNUNET_MessageHeader *message)
728 struct MeshConnection *c;
729 struct GNUNET_MESH_KX *msg;
730 size_t size = ntohs (message->size);
731 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
735 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
737 /* Avoid loopback. */
738 if (GMT_is_loopback (t))
740 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
745 /* Must have a connection. */
746 if (NULL == t->connection_head)
752 msg = (struct GNUNET_MESH_KX *) cbuf;
753 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
754 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
755 c = tunnel_get_connection (t);
758 GNUNET_break (GNUNET_YES == t->destroy);
761 type = ntohs (message->type);
764 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
765 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
766 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
767 msg->reserved = htonl (0);
768 memcpy (&msg[1], message, size);
771 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
776 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
777 /* TODO save handle and cancel in case of a unneeded retransmission */
778 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
783 * Send the ephemeral key on a tunnel.
785 * @param t Tunnel on which to send the key.
788 send_ephemeral (struct MeshTunnel3 *t)
790 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
792 kx_msg.sender_status = htonl (t->estate);
793 send_kx (t, &kx_msg.header);
797 * Send a ping message on a tunnel.
799 * @param t Tunnel on which to send the ping.
802 send_ping (struct MeshTunnel3 *t)
804 struct GNUNET_MESH_KX_Ping msg;
806 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
807 msg.header.size = htons (sizeof (msg));
808 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
809 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
810 msg.target = *GMP_get_id (t->peer);
811 msg.nonce = t->kx_ctx->challenge;
813 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
814 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&msg.target));
815 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
816 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
817 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg.target));
819 send_kx (t, &msg.header);
824 * Send a pong message on a tunnel.
826 * @param t Tunnel on which to send the pong.
827 * @param challenge Value sent in the ping that we have to send back.
830 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
832 struct GNUNET_MESH_KX_Pong msg;
834 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
835 msg.header.size = htons (sizeof (msg));
836 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
837 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
838 msg.nonce = challenge;
839 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
840 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
841 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
843 send_kx (t, &msg.header);
848 * Initiate a rekey with the remote peer.
850 * @param cls Closure (tunnel).
851 * @param tc TaskContext.
854 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
856 struct MeshTunnel3 *t = cls;
858 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
860 LOG (GNUNET_ERROR_TYPE_DEBUG, "Re-key Tunnel\n");
861 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
864 if (NULL == t->kx_ctx)
866 LOG (GNUNET_ERROR_TYPE_DEBUG, " new kx ctx\n");
867 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
868 t->kx_ctx->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
870 t->kx_ctx->d_key_old = t->d_key;
875 case MESH_TUNNEL3_KEY_UNINITIALIZED:
876 t->estate = MESH_TUNNEL3_KEY_SENT;
878 case MESH_TUNNEL3_KEY_SENT:
880 case MESH_TUNNEL3_KEY_PING:
881 case MESH_TUNNEL3_KEY_OK:
883 t->estate = MESH_TUNNEL3_KEY_PING;
886 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->estate);
889 LOG (GNUNET_ERROR_TYPE_DEBUG, " next call in %s\n",
890 GNUNET_STRINGS_relative_time_to_string (REKEY_WAIT, GNUNET_YES));
891 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
896 * Out ephemeral key has changed, create new session key on all tunnels.
898 * @param cls Closure (size of the hashmap).
899 * @param key Current public key.
900 * @param value Value in the hash map (tunnel).
902 * @return #GNUNET_YES, so we should continue to iterate,
905 rekey_iterator (void *cls,
906 const struct GNUNET_PeerIdentity *key,
909 struct MeshTunnel3 *t = value;
910 struct GNUNET_TIME_Relative delay;
914 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
917 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
918 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
919 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
926 * Create a new ephemeral key and key message, schedule next rekeying.
928 * @param cls Closure (unused).
929 * @param tc TaskContext.
932 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
934 struct GNUNET_TIME_Absolute time;
937 rekey_task = GNUNET_SCHEDULER_NO_TASK;
939 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
942 GNUNET_free_non_null (my_ephemeral_key);
943 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
945 time = GNUNET_TIME_absolute_get ();
946 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
947 time = GNUNET_TIME_absolute_add (time, rekey_period);
948 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
949 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
950 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
952 GNUNET_assert (GNUNET_OK ==
953 GNUNET_CRYPTO_eddsa_sign (my_private_key,
957 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
958 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
960 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
965 * Called only on shutdown, destroy every tunnel.
967 * @param cls Closure (unused).
968 * @param key Current public key.
969 * @param value Value in the hash map (tunnel).
971 * @return #GNUNET_YES, so we should continue to iterate,
974 destroy_iterator (void *cls,
975 const struct GNUNET_PeerIdentity *key,
978 struct MeshTunnel3 *t = value;
986 * Demultiplex data per channel and call appropriate channel handler.
988 * @param t Tunnel on which the data came.
989 * @param msg Data message.
990 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
991 * #GNUNET_YES if message is FWD on the respective channel (loopback)
992 * #GNUNET_NO if message is BCK on the respective channel (loopback)
993 * #GNUNET_SYSERR if message on a one-ended channel (remote)
996 handle_data (struct MeshTunnel3 *t,
997 const struct GNUNET_MESH_Data *msg,
1000 struct MeshChannel *ch;
1004 size = ntohs (msg->header.size);
1006 sizeof (struct GNUNET_MESH_Data) +
1007 sizeof (struct GNUNET_MessageHeader))
1012 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
1013 GM_m2s (ntohs (msg[1].header.type)));
1016 ch = GMT_get_channel (t, ntohl (msg->chid));
1019 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
1021 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1026 GMCH_handle_data (ch, msg, fwd);
1031 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
1033 * @param t Tunnel on which the DATA ACK came.
1034 * @param msg DATA ACK message.
1035 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1036 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1037 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1038 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1041 handle_data_ack (struct MeshTunnel3 *t,
1042 const struct GNUNET_MESH_DataACK *msg,
1045 struct MeshChannel *ch;
1049 size = ntohs (msg->header.size);
1050 if (size != sizeof (struct GNUNET_MESH_DataACK))
1057 ch = GMT_get_channel (t, ntohl (msg->chid));
1060 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
1062 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1067 GMCH_handle_data_ack (ch, msg, fwd);
1072 * Handle channel create.
1074 * @param t Tunnel on which the data came.
1075 * @param msg Data message.
1078 handle_ch_create (struct MeshTunnel3 *t,
1079 const struct GNUNET_MESH_ChannelCreate *msg)
1081 struct MeshChannel *ch;
1085 size = ntohs (msg->header.size);
1086 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
1093 ch = GMT_get_channel (t, ntohl (msg->chid));
1094 if (NULL != ch && ! GMT_is_loopback (t))
1096 /* Probably a retransmission, safe to ignore */
1097 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
1101 ch = GMCH_handle_create (t, msg);
1104 GMT_add_channel (t, ch);
1110 * Handle channel NACK: check correctness and call channel handler for NACKs.
1112 * @param t Tunnel on which the NACK came.
1113 * @param msg NACK message.
1116 handle_ch_nack (struct MeshTunnel3 *t,
1117 const struct GNUNET_MESH_ChannelManage *msg)
1119 struct MeshChannel *ch;
1123 size = ntohs (msg->header.size);
1124 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1131 ch = GMT_get_channel (t, ntohl (msg->chid));
1134 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
1136 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1141 GMCH_handle_nack (ch);
1146 * Handle a CHANNEL ACK (SYNACK/ACK).
1148 * @param t Tunnel on which the CHANNEL ACK came.
1149 * @param msg CHANNEL ACK message.
1150 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1151 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1152 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1153 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1156 handle_ch_ack (struct MeshTunnel3 *t,
1157 const struct GNUNET_MESH_ChannelManage *msg,
1160 struct MeshChannel *ch;
1164 size = ntohs (msg->header.size);
1165 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1172 ch = GMT_get_channel (t, ntohl (msg->chid));
1175 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1177 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1182 GMCH_handle_ack (ch, msg, fwd);
1188 * Handle a channel destruction message.
1190 * @param t Tunnel on which the message came.
1191 * @param msg Channel destroy message.
1192 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1193 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1194 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1195 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1198 handle_ch_destroy (struct MeshTunnel3 *t,
1199 const struct GNUNET_MESH_ChannelManage *msg,
1202 struct MeshChannel *ch;
1206 size = ntohs (msg->header.size);
1207 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1214 ch = GMT_get_channel (t, ntohl (msg->chid));
1217 /* Probably a retransmission, safe to ignore */
1221 GMCH_handle_destroy (ch, msg, fwd);
1226 * The peer's ephemeral key has changed: update the symmetrical keys.
1228 * @param t Tunnel this message came on.
1229 * @param msg Key eXchange message.
1232 handle_ephemeral (struct MeshTunnel3 *t,
1233 const struct GNUNET_MESH_KX_Ephemeral *msg)
1235 struct GNUNET_HashCode km;
1236 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1238 if (GNUNET_OK != check_ephemeral (t, msg))
1240 GNUNET_break_op (0);
1243 derive_key_material (&km, &msg->ephemeral_key);
1244 LOG (GNUNET_ERROR_TYPE_DEBUG, " km is %s\n", GNUNET_h2s (&km));
1245 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1246 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1247 if (MESH_TUNNEL3_KEY_SENT == t->estate)
1249 LOG (GNUNET_ERROR_TYPE_DEBUG, " our key was sent, send ping\n");
1251 t->estate = MESH_TUNNEL3_KEY_PING;
1257 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1258 * Answer with by retransmitting the challenge with the "opposite" key.
1260 * @param t Tunnel this message came on.
1261 * @param msg Key eXchange Ping message.
1264 handle_ping (struct MeshTunnel3 *t,
1265 const struct GNUNET_MESH_KX_Ping *msg)
1267 struct GNUNET_MESH_KX_Ping res;
1269 if (ntohs (msg->header.size) != sizeof (res))
1271 GNUNET_break_op (0);
1275 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1276 t_decrypt (t, &res.target, &msg->target, ping_encryption_size (), msg->iv);
1277 if (0 != memcmp (&my_full_id, &res.target, sizeof (my_full_id)))
1279 GNUNET_break_op (0);
1280 LOG (GNUNET_ERROR_TYPE_DEBUG, " e got %u\n", msg->nonce);
1281 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg->target));
1282 LOG (GNUNET_ERROR_TYPE_DEBUG, " got %u\n", res.nonce);
1283 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&res.target));
1287 send_pong (t, res.nonce);
1292 * Peer has answer to our challenge.
1293 * If answer is successful, consider the key exchange finished and clean
1294 * up all related state.
1296 * @param t Tunnel this message came on.
1297 * @param msg Key eXchange Pong message.
1300 handle_pong (struct MeshTunnel3 *t,
1301 const struct GNUNET_MESH_KX_Pong *msg)
1305 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1306 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1308 GNUNET_break_op (0);
1311 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1313 if (challenge != t->kx_ctx->challenge)
1315 LOG (GNUNET_ERROR_TYPE_DEBUG,
1316 "Wrong PONG challenge: %u (e: %u). Expected: %u.\n",
1317 challenge, msg->nonce, t->kx_ctx->challenge);
1318 GNUNET_break_op (0);
1321 GNUNET_SCHEDULER_cancel (t->rekey_task);
1322 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1323 GNUNET_free (t->kx_ctx);
1325 GMT_change_estate (t, MESH_TUNNEL3_KEY_OK);
1330 * Demultiplex by message type and call appropriate handler for a message
1331 * towards a channel of a local tunnel.
1333 * @param t Tunnel this message came on.
1334 * @param msgh Message header.
1335 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1336 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1337 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1338 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1341 handle_decrypted (struct MeshTunnel3 *t,
1342 const struct GNUNET_MessageHeader *msgh,
1347 type = ntohs (msgh->type);
1348 LOG (GNUNET_ERROR_TYPE_DEBUG,
1349 "Got a %s message!\n",
1354 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1355 /* Don't send hop ACK, wait for client to ACK */
1356 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1359 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1360 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1363 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1364 handle_ch_create (t,
1365 (struct GNUNET_MESH_ChannelCreate *) msgh);
1368 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1370 (struct GNUNET_MESH_ChannelManage *) msgh);
1373 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1375 (struct GNUNET_MESH_ChannelManage *) msgh,
1379 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1380 handle_ch_destroy (t,
1381 (struct GNUNET_MESH_ChannelManage *) msgh,
1386 GNUNET_break_op (0);
1387 LOG (GNUNET_ERROR_TYPE_DEBUG,
1388 "end-to-end message not known (%u)\n",
1389 ntohs (msgh->type));
1393 /******************************************************************************/
1394 /******************************** API ***********************************/
1395 /******************************************************************************/
1398 * Decrypt and demultiplex by message type. Call appropriate handler
1399 * for every message.
1401 * @param t Tunnel this message came on.
1402 * @param msg Encrypted message.
1405 GMT_handle_encrypted (struct MeshTunnel3 *t,
1406 const struct GNUNET_MESH_Encrypted *msg)
1408 size_t size = ntohs (msg->header.size);
1409 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1410 size_t decrypted_size;
1411 char cbuf [payload_size];
1412 struct GNUNET_MessageHeader *msgh;
1415 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1417 while (off < decrypted_size)
1419 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1420 handle_decrypted (t, msgh, GNUNET_SYSERR);
1421 off += ntohs (msgh->size);
1427 * Demultiplex an encapsulated KX message by message type.
1429 * @param t Tunnel on which the message came.
1430 * @param message Payload of KX message.
1433 GMT_handle_kx (struct MeshTunnel3 *t,
1434 const struct GNUNET_MessageHeader *message)
1438 type = ntohs (message->type);
1439 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1442 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1443 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1446 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1447 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1450 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1451 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1455 GNUNET_break_op (0);
1456 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1462 * Initialize the tunnel subsystem.
1464 * @param c Configuration handle.
1465 * @param key ECC private key, to derive all other keys and do crypto.
1468 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1469 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1471 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1473 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1476 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1477 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1481 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1484 rekey_period = GNUNET_TIME_UNIT_DAYS;
1487 my_private_key = key;
1488 kx_msg.header.size = htons (sizeof (kx_msg));
1489 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1490 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1491 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1492 kx_msg.origin_identity = my_full_id;
1493 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1495 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1500 * Shut down the tunnel subsystem.
1505 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1507 GNUNET_SCHEDULER_cancel (rekey_task);
1508 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1510 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &destroy_iterator, NULL);
1511 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1518 * @param destination Peer this tunnel is towards.
1520 struct MeshTunnel3 *
1521 GMT_new (struct MeshPeer *destination)
1523 struct MeshTunnel3 *t;
1525 t = GNUNET_new (struct MeshTunnel3);
1527 t->peer = destination;
1530 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1531 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1542 * Change the tunnel's connection state.
1544 * @param t Tunnel whose connection state to change.
1545 * @param cstate New connection state.
1548 GMT_change_cstate (struct MeshTunnel3* t, enum MeshTunnel3CState cstate)
1552 LOG (GNUNET_ERROR_TYPE_DEBUG,
1553 "Tunnel %s cstate was %s\n",
1554 GMP_2s (t->peer), cstate2s (t->cstate));
1555 LOG (GNUNET_ERROR_TYPE_DEBUG,
1556 "Tunnel %s cstate is now %s\n",
1557 GMP_2s (t->peer), cstate2s (cstate));
1558 if (myid != GMP_get_short_id (t->peer) &&
1559 MESH_TUNNEL3_READY != t->cstate &&
1560 MESH_TUNNEL3_READY == cstate)
1563 if (MESH_TUNNEL3_KEY_OK == t->estate)
1565 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered send queued data\n");
1566 send_queued_data (t);
1568 else if (MESH_TUNNEL3_KEY_UNINITIALIZED == t->estate)
1570 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1571 rekey_tunnel (t, NULL);
1576 if (MESH_TUNNEL3_READY == cstate && 3 <= GMT_count_connections (t))
1578 GMP_stop_search (t->peer);
1583 * Change the tunnel encryption state.
1585 * @param t Tunnel whose encryption state to change.
1586 * @param state New encryption state.
1589 GMT_change_estate (struct MeshTunnel3* t, enum MeshTunnel3EState state)
1593 LOG (GNUNET_ERROR_TYPE_DEBUG,
1594 "Tunnel %s estate was %s\n",
1595 GMP_2s (t->peer), estate2s (t->estate));
1596 LOG (GNUNET_ERROR_TYPE_DEBUG,
1597 "Tunnel %s estate is now %s\n",
1598 GMP_2s (t->peer), estate2s (state));
1599 if (myid != GMP_get_short_id (t->peer) &&
1600 MESH_TUNNEL3_KEY_OK != t->estate && MESH_TUNNEL3_KEY_OK == state)
1603 send_queued_data (t);
1611 * Add a connection to a tunnel.
1614 * @param c Connection.
1617 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1619 struct MeshTConnection *aux;
1621 GNUNET_assert (NULL != c);
1623 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1627 aux = GNUNET_new (struct MeshTConnection);
1629 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1634 * Remove a connection from a tunnel.
1637 * @param c Connection.
1640 GMT_remove_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1642 struct MeshTConnection *aux;
1644 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1647 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1655 * Add a channel to a tunnel.
1658 * @param ch Channel.
1661 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1663 struct MeshTChannel *aux;
1665 GNUNET_assert (NULL != ch);
1667 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1669 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1671 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1676 aux = GNUNET_new (struct MeshTChannel);
1678 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1679 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1681 if (GNUNET_YES == t->destroy)
1683 t->destroy = GNUNET_NO;
1684 LOG (GNUNET_ERROR_TYPE_DEBUG, " undo destroy!\n");
1690 * Remove a channel from a tunnel.
1693 * @param ch Channel.
1696 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1698 struct MeshTChannel *aux;
1700 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1701 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1705 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1706 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1715 * Search for a channel by global ID.
1717 * @param t Tunnel containing the channel.
1718 * @param chid Public channel number.
1720 * @return channel handler, NULL if doesn't exist
1722 struct MeshChannel *
1723 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1725 struct MeshTChannel *iter;
1730 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1732 if (GMCH_get_id (iter->ch) == chid)
1736 return NULL == iter ? NULL : iter->ch;
1741 * Tunnel is empty: destroy it.
1743 * Notifies all connections about the destruction.
1745 * @param t Tunnel to destroy.
1748 GMT_destroy_empty (struct MeshTunnel3 *t)
1750 struct MeshTConnection *iter;
1752 LOG (GNUNET_ERROR_TYPE_DEBUG, "Tunnel empty: destroying scheduled\n");
1753 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1755 GMC_send_destroy (iter->c);
1758 t->cstate = MESH_TUNNEL3_NEW;
1759 t->destroy = GNUNET_YES;
1764 * Destroy tunnel if empty (no more channels).
1766 * @param t Tunnel to destroy if empty.
1769 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1771 if (1 < GMT_count_channels (t))
1774 GMT_destroy_empty (t);
1779 * Destroy the tunnel.
1781 * This function does not generate any warning traffic to clients or peers.
1784 * Cancel messages belonging to this tunnel queued to neighbors.
1785 * Free any allocated resources linked to the tunnel.
1787 * @param t The tunnel to destroy.
1790 GMT_destroy (struct MeshTunnel3 *t)
1792 struct MeshTConnection *iter_c;
1793 struct MeshTConnection *next_c;
1794 struct MeshTChannel *iter_ch;
1795 struct MeshTChannel *next_ch;
1800 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
1802 GNUNET_break (GNUNET_YES ==
1803 GNUNET_CONTAINER_multipeermap_remove (tunnels,
1804 GMP_get_id (t->peer), t));
1806 for (iter_c = t->connection_head; NULL != iter_c; iter_c = next_c)
1808 next_c = iter_c->next;
1809 GMC_destroy (iter_c->c);
1811 for (iter_ch = t->channel_head; NULL != iter_ch; iter_ch = next_ch)
1813 next_ch = iter_ch->next;
1814 GMCH_destroy (iter_ch->ch);
1815 /* Should only happen on shutdown, but it's ok. */
1818 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
1819 GMP_set_tunnel (t->peer, NULL);
1821 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1822 GNUNET_SCHEDULER_cancel (t->rekey_task);
1829 * @brief Use the given path for the tunnel.
1830 * Update the next and prev hops (and RCs).
1831 * (Re)start the path refresh in case the tunnel is locally owned.
1833 * @param t Tunnel to update.
1834 * @param p Path to use.
1836 * @return Connection created.
1838 struct MeshConnection *
1839 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
1841 struct MeshConnection *c;
1842 struct GNUNET_HashCode cid;
1843 unsigned int own_pos;
1845 if (NULL == t || NULL == p)
1851 for (own_pos = 0; own_pos < p->length; own_pos++)
1853 if (p->peers[own_pos] == myid)
1856 if (own_pos > p->length - 1)
1862 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
1863 c = GMC_new (&cid, t, p, own_pos);
1866 /* Path was flawed */
1869 GMT_add_connection (t, c);
1875 * Count established (ready) connections of a tunnel.
1877 * @param t Tunnel on which to count.
1879 * @return Number of connections.
1882 GMT_count_connections (struct MeshTunnel3 *t)
1884 struct MeshTConnection *iter;
1887 for (count = 0, iter = t->connection_head;
1889 iter = iter->next, count++);
1895 * Count channels of a tunnel.
1897 * @param t Tunnel on which to count.
1899 * @return Number of channels.
1902 GMT_count_channels (struct MeshTunnel3 *t)
1904 struct MeshTChannel *iter;
1907 for (count = 0, iter = t->channel_head;
1909 iter = iter->next, count++) /* skip */;
1916 * Get the connectivity state of a tunnel.
1920 * @return Tunnel's connectivity state.
1922 enum MeshTunnel3CState
1923 GMT_get_cstate (struct MeshTunnel3 *t)
1928 return (enum MeshTunnel3CState) -1;
1935 * Get the maximum buffer space for a tunnel towards a local client.
1939 * @return Biggest buffer space offered by any channel in the tunnel.
1942 GMT_get_channels_buffer (struct MeshTunnel3 *t)
1944 struct MeshTChannel *iter;
1945 unsigned int buffer;
1946 unsigned int ch_buf;
1948 if (NULL == t->channel_head)
1950 /* Probably getting buffer for a channel create/handshake. */
1955 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1957 ch_buf = get_channel_buffer (iter);
1958 if (ch_buf > buffer)
1966 * Get the total buffer space for a tunnel for P2P traffic.
1970 * @return Buffer space offered by all connections in the tunnel.
1973 GMT_get_connections_buffer (struct MeshTunnel3 *t)
1975 struct MeshTConnection *iter;
1976 unsigned int buffer;
1979 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1981 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
1985 buffer += get_connection_buffer (iter);
1993 * Get the tunnel's destination.
1997 * @return ID of the destination peer.
1999 const struct GNUNET_PeerIdentity *
2000 GMT_get_destination (struct MeshTunnel3 *t)
2002 return GMP_get_id (t->peer);
2007 * Get the tunnel's next free global channel ID.
2011 * @return GID of a channel free to use.
2014 GMT_get_next_chid (struct MeshTunnel3 *t)
2016 MESH_ChannelNumber chid;
2017 MESH_ChannelNumber mask;
2020 /* Set bit 30 depending on the ID relationship. Bit 31 is always 0 for GID.
2021 * If our ID is bigger or loopback tunnel, start at 0, bit 30 = 0
2022 * If peer's ID is bigger, start at 0x4... bit 30 = 1
2024 result = GNUNET_CRYPTO_cmp_peer_identity (&my_full_id, GMP_get_id (t->peer));
2030 while (NULL != GMT_get_channel (t, t->next_chid))
2032 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
2033 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2034 t->next_chid |= mask;
2036 chid = t->next_chid;
2037 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2038 t->next_chid |= mask;
2045 * Send ACK on one or more channels due to buffer in connections.
2047 * @param t Channel which has some free buffer space.
2050 GMT_unchoke_channels (struct MeshTunnel3 *t)
2052 struct MeshTChannel *iter;
2053 unsigned int buffer;
2054 unsigned int channels = GMT_count_channels (t);
2055 unsigned int choked_n;
2056 struct MeshChannel *choked[channels];
2058 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
2059 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
2060 if (NULL != t->channel_head)
2061 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
2063 /* Get buffer space */
2064 buffer = GMT_get_connections_buffer (t);
2070 /* Count and remember choked channels */
2072 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2074 if (GNUNET_NO == get_channel_allowed (iter))
2076 choked[choked_n++] = iter->ch;
2080 /* Unchoke random channels */
2081 while (0 < buffer && 0 < choked_n)
2083 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2085 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
2088 choked[r] = choked[choked_n];
2094 * Send ACK on one or more connections due to buffer space to the client.
2096 * Iterates all connections of the tunnel and sends ACKs appropriately.
2101 GMT_send_connection_acks (struct MeshTunnel3 *t)
2103 struct MeshTConnection *iter;
2106 uint32_t allow_per_connection;
2108 unsigned int buffer;
2110 LOG (GNUNET_ERROR_TYPE_DEBUG,
2111 "Tunnel send connection ACKs on %s\n",
2120 buffer = GMT_get_channels_buffer (t);
2122 /* Count connections, how many messages are already allowed */
2123 cs = GMT_count_connections (t);
2124 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
2126 allowed += get_connection_allowed (iter);
2129 /* Make sure there is no overflow */
2130 if (allowed > buffer)
2135 /* Authorize connections to send more data */
2136 to_allow = buffer; /* - allowed; */
2138 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
2140 allow_per_connection = to_allow/cs;
2141 to_allow -= allow_per_connection;
2143 if (get_connection_allowed (iter) > 64 / 3)
2147 GMC_allow (iter->c, buffer, GMC_is_origin (iter->c, GNUNET_YES));
2150 GNUNET_break (to_allow == 0);
2155 * Callback called when a queued message is sent.
2157 * Calculates the average time and connection packet tracking.
2159 * @param cls Closure (TunnelQueue handle).
2160 * @param c Connection this message was on.
2161 * @param q Connection queue handle (unused).
2162 * @param type Type of message sent.
2163 * @param fwd Was this a FWD going message?
2164 * @param size Size of the message.
2167 message_sent (void *cls,
2168 struct MeshConnection *c,
2169 struct MeshConnectionQueue *q,
2170 uint16_t type, int fwd, size_t size)
2172 struct MeshTunnel3Queue *qt = cls;
2174 GNUNET_assert (NULL != qt->cont);
2175 qt->cont (qt->cont_cls, GMC_get_tunnel (c), qt, type, size);
2181 * Cancel a previously sent message while it's in the queue.
2183 * ONLY can be called before the continuation given to the send function
2184 * is called. Once the continuation is called, the message is no longer in the
2187 * @param q Handle to the queue.
2190 GMT_cancel (struct MeshTunnel3Queue *q)
2195 /* message_sent() will be called and free q */
2197 else if (NULL != q->tq)
2199 unqueue_data (q->tq);
2209 * Sends an already built message on a tunnel, encrypting it and
2210 * choosing the best connection.
2212 * @param message Message to send. Function modifies it.
2213 * @param t Tunnel on which this message is transmitted.
2214 * @param ch Channel on which this message is transmitted.
2215 * @param force Force the tunnel to take the message (buffer overfill).
2216 * @param cont Continuation to call once message is really sent.
2217 * @param cont_cls Closure for @c cont.
2219 * @return Handle to cancel message. NULL if @c cont is NULL.
2221 struct MeshTunnel3Queue *
2222 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2223 struct MeshTunnel3 *t, struct MeshChannel *ch,
2225 GMT_sent cont, void *cont_cls)
2227 struct MeshTunnel3Queue *q;
2228 struct MeshConnection *c;
2229 struct GNUNET_MESH_Encrypted *msg;
2230 size_t size = ntohs (message->size);
2231 size_t encrypted_size;
2232 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
2237 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
2239 if (GNUNET_NO == is_ready (t))
2241 q = GNUNET_new (struct MeshTunnel3Queue);
2242 q->tq = queue_data (t, ch, message);
2246 GNUNET_assert (GNUNET_NO == GMT_is_loopback (t));
2248 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
2249 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
2250 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
2252 encrypted_size = t_encrypt (t, &msg[1], message, size, iv);
2253 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + encrypted_size);
2254 c = tunnel_get_connection (t);
2257 GNUNET_break (GNUNET_YES == t->destroy);
2260 type = ntohs (message->type);
2263 case GNUNET_MESSAGE_TYPE_MESH_DATA:
2264 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
2265 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
2266 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
2267 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
2268 msg->cid = *GMC_get_id (c);
2269 msg->ttl = htonl (default_ttl);
2272 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
2277 fwd = GMC_is_origin (c, GNUNET_YES);
2281 (void) GMC_send_prebuilt_message (&msg->header, c, fwd, force, NULL, NULL);
2284 q = GNUNET_new (struct MeshTunnel3Queue); /* FIXME valgrind: leak*/
2285 q->q = GMC_send_prebuilt_message (&msg->header, c, fwd, force,
2288 q->cont_cls = cont_cls;
2294 * Is the tunnel directed towards the local peer?
2298 * @return #GNUNET_YES if it is loopback.
2301 GMT_is_loopback (const struct MeshTunnel3 *t)
2303 return (myid == GMP_get_short_id (t->peer));
2308 * Is the tunnel this path already?
2313 * @return #GNUNET_YES a connection uses this path.
2316 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2318 struct MeshTConnection *iter;
2320 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2321 if (GMC_get_path (iter->c) == p)
2329 * Get a cost of a path for a tunnel considering existing connections.
2332 * @param path Candidate path.
2334 * @return Cost of the path (path length + number of overlapping nodes)
2337 GMT_get_path_cost (const struct MeshTunnel3 *t,
2338 const struct MeshPeerPath *path)
2340 struct MeshTConnection *iter;
2341 const struct MeshPeerPath *aux;
2342 unsigned int overlap;
2350 GNUNET_assert (NULL != t);
2352 for (i = 0; i < path->length; i++)
2354 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2356 aux = GMC_get_path (iter->c);
2360 for (j = 0; j < aux->length; j++)
2362 if (path->peers[i] == aux->peers[j])
2370 return (path->length + overlap) * (path->score * -1);
2375 * Get the static string for the peer this tunnel is directed.
2379 * @return Static string the destination peer's ID.
2382 GMT_2s (const struct MeshTunnel3 *t)
2387 return GMP_2s (t->peer);