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, 30)
39 /******************************************************************************/
40 /******************************** STRUCTS **********************************/
41 /******************************************************************************/
45 struct MeshTChannel *next;
46 struct MeshTChannel *prev;
47 struct MeshChannel *ch;
50 struct MeshTConnection
52 struct MeshTConnection *next;
53 struct MeshTConnection *prev;
54 struct MeshConnection *c;
58 * Structure used during a Key eXchange.
60 struct MeshTunnelKXCtx
63 * Decryption ("their") old key, for decrypting traffic sent by the
64 * other end before the key exchange started.
66 struct GNUNET_CRYPTO_SymmetricSessionKey d_key_old;
69 * Challenge to send in a ping and expect in the pong.
75 * Struct containing all information regarding a tunnel to a peer.
80 * Endpoint of the tunnel.
82 struct MeshPeer *peer;
85 * State of the tunnel.
87 enum MeshTunnel3State state;
90 * Key eXchange context.
92 struct MeshTunnelKXCtx *kx_ctx;
95 * Encryption ("our") key.
97 struct GNUNET_CRYPTO_SymmetricSessionKey e_key;
100 * Decryption ("their") key.
102 struct GNUNET_CRYPTO_SymmetricSessionKey d_key;
105 * Task to start the rekey process.
107 GNUNET_SCHEDULER_TaskIdentifier rekey_task;
110 * Paths that are actively used to reach the destination peer.
112 struct MeshTConnection *connection_head;
113 struct MeshTConnection *connection_tail;
116 * Next connection number.
121 * Channels inside this tunnel.
123 struct MeshTChannel *channel_head;
124 struct MeshTChannel *channel_tail;
127 * Channel ID for the next created channel.
129 MESH_ChannelNumber next_chid;
132 * Destroy flag: if true, destroy on last message.
137 * Queued messages, to transmit once tunnel gets connected.
139 struct MeshTunnelQueue *tq_head;
140 struct MeshTunnelQueue *tq_tail;
145 * Struct used to queue messages in a tunnel.
147 struct MeshTunnelQueue
152 struct MeshTunnelQueue *next;
153 struct MeshTunnelQueue *prev;
158 struct MeshChannel *ch;
163 /* struct GNUNET_MessageHeader *msg; */
167 /******************************************************************************/
168 /******************************* GLOBALS ***********************************/
169 /******************************************************************************/
172 * Global handle to the statistics service.
174 extern struct GNUNET_STATISTICS_Handle *stats;
177 * Local peer own ID (memory efficient handle).
179 extern GNUNET_PEER_Id myid;
182 * Local peer own ID (full value).
184 extern struct GNUNET_PeerIdentity my_full_id;
188 * Set of all tunnels, in order to trigger a new exchange on rekey.
189 * Indexed by peer's ID.
191 static struct GNUNET_CONTAINER_MultiPeerMap *tunnels;
194 * Default TTL for payload packets.
196 static unsigned long long default_ttl;
201 const static struct GNUNET_CRYPTO_EddsaPrivateKey *my_private_key;
204 * Own ephemeral private key.
206 static struct GNUNET_CRYPTO_EcdhePrivateKey *my_ephemeral_key;
209 * Cached message used to perform a key exchange.
211 static struct GNUNET_MESH_KX_Ephemeral kx_msg;
214 * Task to generate a new ephemeral key.
216 static GNUNET_SCHEDULER_TaskIdentifier rekey_task;
221 static struct GNUNET_TIME_Relative rekey_period;
223 /******************************************************************************/
224 /******************************** STATIC ***********************************/
225 /******************************************************************************/
228 * Get string description for tunnel state.
230 * @param s Tunnel state.
232 * @return String representation.
235 GMT_state2s (enum MeshTunnel3State s)
237 static char buf[128];
241 case MESH_TUNNEL3_NEW:
242 return "MESH_TUNNEL3_NEW";
243 case MESH_TUNNEL3_SEARCHING:
244 return "MESH_TUNNEL3_SEARCHING";
245 case MESH_TUNNEL3_WAITING:
246 return "MESH_TUNNEL3_WAITING";
247 case MESH_TUNNEL3_KEY_SENT:
248 return "MESH_TUNNEL3_KEY_SENT";
249 case MESH_TUNNEL3_READY:
250 return "MESH_TUNNEL3_READY";
251 case MESH_TUNNEL3_RECONNECTING:
252 return "MESH_TUNNEL3_RECONNECTING";
253 case MESH_TUNNEL3_REKEY:
254 return "MESH_TUNNEL3_REKEY";
257 sprintf (buf, "%u (UNKNOWN STATE)", s);
264 * Ephemeral key message purpose size.
266 * @return Size of the part of the ephemeral key message that must be signed.
269 ephemeral_purpose_size (void)
271 return sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
272 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
273 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
274 sizeof (struct GNUNET_CRYPTO_EcdhePublicKey) +
275 sizeof (struct GNUNET_PeerIdentity);
280 * Size of the encrypted part of a ping message.
282 * @return Size of the encrypted part of a ping message.
285 ping_encryption_size (void)
287 return sizeof (struct GNUNET_PeerIdentity) + sizeof (uint32_t);
292 * Get the channel's buffer. ONLY FOR NON-LOOPBACK CHANNELS!!
294 * @param tch Tunnel's channel handle.
296 * @return Amount of messages the channel can still buffer towards the client.
299 get_channel_buffer (const struct MeshTChannel *tch)
303 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
304 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
306 return GMCH_get_buffer (tch->ch, fwd);
311 * Get the channel's allowance status.
313 * @param tch Tunnel's channel handle.
315 * @return #GNUNET_YES if we allowed the client to send data to us.
318 get_channel_allowed (const struct MeshTChannel *tch)
322 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
323 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
325 return GMCH_get_allowed (tch->ch, fwd);
330 * Get the connection's buffer.
332 * @param tc Tunnel's connection handle.
334 * @return Amount of messages the connection can still buffer.
337 get_connection_buffer (const struct MeshTConnection *tc)
341 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
342 fwd = GMC_is_origin (tc->c, GNUNET_YES);
344 return GMC_get_buffer (tc->c, fwd);
349 * Get the connection's allowance.
351 * @param tc Tunnel's connection handle.
353 * @return Amount of messages we have allowed the next peer to send us.
356 get_connection_allowed (const struct MeshTConnection *tc)
360 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
361 fwd = GMC_is_origin (tc->c, GNUNET_YES);
363 return GMC_get_allowed (tc->c, fwd);
368 * Check that a ephemeral key message s well formed and correctly signed.
370 * @param t Tunnel on which the message came.
371 * @param msg The ephemeral key message.
373 * @return GNUNET_OK if message is fine, GNUNET_SYSERR otherwise.
376 check_ephemeral (struct MeshTunnel3 *t,
377 const struct GNUNET_MESH_KX_Ephemeral *msg)
379 /* Check message size */
380 if (ntohs (msg->header.size) != sizeof (struct GNUNET_MESH_KX_Ephemeral))
381 return GNUNET_SYSERR;
383 /* Check signature size */
384 if (ntohl (msg->purpose.size) != ephemeral_purpose_size ())
385 return GNUNET_SYSERR;
388 if (0 != memcmp (&msg->origin_identity,
389 GMP_get_id (t->peer),
390 sizeof (struct GNUNET_PeerIdentity)))
391 return GNUNET_SYSERR;
393 /* Check signature */
395 GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_MESH_KX,
398 &msg->origin_identity.public_key))
399 return GNUNET_SYSERR;
406 * Encrypt data with the tunnel key.
408 * @param t Tunnel whose key to use.
409 * @param dst Destination for the encrypted data.
410 * @param src Source of the plaintext. Can overlap with @c dst.
411 * @param size Size of the plaintext.
412 * @param iv Initialization Vector to use.
415 t_encrypt (struct MeshTunnel3 *t,
416 void *dst, const void *src,
417 size_t size, uint32_t iv)
419 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
421 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->e_key, &iv, sizeof (uint32_t), NULL);
422 return GNUNET_CRYPTO_symmetric_encrypt (src, size, &t->e_key, &siv, dst);
427 * Decrypt data with the tunnel key.
429 * @param t Tunnel whose key to use.
430 * @param dst Destination for the plaintext.
431 * @param src Source of the encrypted data. Can overlap with @c dst.
432 * @param size Size of the encrypted data.
433 * @param iv Initialization Vector to use.
436 t_decrypt (struct MeshTunnel3 *t,
437 void *dst, const void *src,
438 size_t size, uint32_t iv)
440 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
442 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->d_key, &iv, sizeof (uint32_t), NULL);
443 return GNUNET_CRYPTO_symmetric_decrypt (src, size, &t->d_key, &siv, dst);
448 * Create key material by doing ECDH on the local and remote ephemeral keys.
450 * @param key_material Where to store the key material.
451 * @param ephemeral_key Peer's public ephemeral key.
454 derive_key_material (struct GNUNET_HashCode *key_material,
455 const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key)
458 GNUNET_CRYPTO_ecc_ecdh (my_ephemeral_key,
467 * Create a symmetic key from the identities of both ends and the key material
470 * @param key Destination for the generated key.
471 * @param sender ID of the peer that will encrypt with @c key.
472 * @param receiver ID of the peer that will decrypt with @c key.
473 * @param key_material Hash created with ECDH with the ephemeral keys.
476 derive_symmertic (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
477 const struct GNUNET_PeerIdentity *sender,
478 const struct GNUNET_PeerIdentity *receiver,
479 const struct GNUNET_HashCode *key_material)
481 const char salt[] = "MESH kx salt";
483 GNUNET_CRYPTO_kdf (key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
485 key_material, sizeof (struct GNUNET_HashCode),
486 sender, sizeof (struct GNUNET_PeerIdentity),
487 receiver, sizeof (struct GNUNET_PeerIdentity),
492 * Pick a connection on which send the next data message.
494 * @param t Tunnel on which to send the message.
496 * @return The connection on which to send the next message.
498 static struct MeshConnection *
499 tunnel_get_connection (struct MeshTunnel3 *t)
501 struct MeshTConnection *iter;
502 struct MeshConnection *best;
504 unsigned int lowest_q;
506 LOG (GNUNET_ERROR_TYPE_DEBUG, "tunnel_get_connection %s\n", GMP_2s (t->peer));
509 for (iter = t->connection_head; NULL != iter; iter = iter->next)
511 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s: %u\n",
512 GNUNET_h2s (GMC_get_id (iter->c)), GMC_get_state (iter->c));
513 if (MESH_CONNECTION_READY == GMC_get_state (iter->c))
515 qn = GMC_get_qn (iter->c, GMC_is_origin (iter->c, GNUNET_YES));
516 LOG (GNUNET_ERROR_TYPE_DEBUG, " q_n %u, \n", qn);
529 * Send all cached messages that we can, tunnel is online.
531 * @param t Tunnel that holds the messages. Cannot be loopback.
534 send_queued_data (struct MeshTunnel3 *t)
536 struct MeshTunnelQueue *tq;
537 struct MeshTunnelQueue *next;
540 LOG (GNUNET_ERROR_TYPE_DEBUG,
541 "GMT_send_queued_data on tunnel %s\n",
544 if (GMT_is_loopback (t))
550 room = GMT_get_connections_buffer (t);
551 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
552 for (tq = t->tq_head; NULL != tq && room > 0; tq = next)
554 LOG (GNUNET_ERROR_TYPE_DEBUG, " data on channel %s\n", GMCH_2s (tq->ch));
557 GNUNET_CONTAINER_DLL_remove (t->tq_head, t->tq_tail, tq);
558 GMCH_send_prebuilt_message ((struct GNUNET_MessageHeader *) &tq[1],
559 tq->ch, GMCH_is_origin (tq->ch, GNUNET_YES));
563 LOG (GNUNET_ERROR_TYPE_DEBUG,
564 "GMT_send_queued_data end\n",
572 * Cache a message to be sent once tunnel is online.
574 * @param t Tunnel to hold the message.
575 * @param ch Channel the message is about.
576 * @param msg Message itself (copy will be made).
579 queue_data (struct MeshTunnel3 *t,
580 struct MeshChannel *ch,
581 const struct GNUNET_MessageHeader *msg)
583 struct MeshTunnelQueue *tq;
584 uint16_t size = ntohs (msg->size);
586 if (MESH_TUNNEL3_READY == t->state)
592 tq = GNUNET_malloc (sizeof (struct MeshTunnelQueue) + size);
595 memcpy (&tq[1], msg, size);
596 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tq);
602 * Sends key exchange message on a tunnel, choosing the best connection.
603 * Should not be called on loopback tunnels.
605 * @param t Tunnel on which this message is transmitted.
606 * @param message Message to send. Function modifies it.
609 send_kx (struct MeshTunnel3 *t,
610 const struct GNUNET_MessageHeader *message)
612 struct MeshConnection *c;
613 struct GNUNET_MESH_KX *msg;
614 size_t size = ntohs (message->size);
615 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
619 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
621 /* Avoid loopback. */
622 if (GMT_is_loopback (t))
624 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
629 /* Must have a connection. */
630 if (NULL == t->connection_head)
636 msg = (struct GNUNET_MESH_KX *) cbuf;
637 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
638 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
639 c = tunnel_get_connection (t);
642 GNUNET_break (GNUNET_YES == t->destroy);
645 type = ntohs (message->type);
648 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
649 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
650 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
651 msg->reserved = htonl (0);
652 memcpy (&msg[1], message, size);
655 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
656 GNUNET_MESH_DEBUG_M2S (type));
660 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
661 /* TODO save handle and cancel in case of a unneeded retransmission */
662 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
667 * Send the ephemeral key on a tunnel.
669 * @param t Tunnel on which to send the key.
672 send_ephemeral (struct MeshTunnel3 *t)
674 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
676 kx_msg.sender_status = htonl (t->state);
677 send_kx (t, &kx_msg.header);
681 * Send a ping message on a tunnel.
683 * @param t Tunnel on which to send the ping.
686 send_ping (struct MeshTunnel3 *t)
688 struct GNUNET_MESH_KX_Ping msg;
690 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
691 msg.header.size = htons (sizeof (msg));
692 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
693 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
694 msg.target = *GMP_get_id (t->peer);
695 msg.nonce = t->kx_ctx->challenge;
697 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
698 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&msg.target));
699 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
700 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
701 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg.target));
703 send_kx (t, &msg.header);
708 * Send a pong message on a tunnel.
710 * @param t Tunnel on which to send the pong.
711 * @param challenge Value sent in the ping that we have to send back.
714 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
716 struct GNUNET_MESH_KX_Pong msg;
718 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
719 msg.header.size = htons (sizeof (msg));
720 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
721 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
722 msg.nonce = challenge;
723 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
724 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
725 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
727 send_kx (t, &msg.header);
732 * Initiate a rekey with the remote peer.
734 * @param cls Closure (tunnel).
735 * @param tc TaskContext.
738 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
740 struct MeshTunnel3 *t = cls;
742 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
744 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
747 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
748 t->kx_ctx->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
750 t->kx_ctx->d_key_old = t->d_key;
752 if (MESH_TUNNEL3_READY == t->state || MESH_TUNNEL3_REKEY == t->state)
755 t->state = MESH_TUNNEL3_REKEY;
757 else if (MESH_TUNNEL3_WAITING == t->state)
759 t->state = MESH_TUNNEL3_KEY_SENT;
763 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->state);
766 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
771 * Out ephemeral key has changed, create new session key on all tunnels.
773 * @param cls Closure (size of the hashmap).
774 * @param key Current public key.
775 * @param value Value in the hash map (tunnel).
777 * @return #GNUNET_YES, so we should continue to iterate,
780 rekey_iterator (void *cls,
781 const struct GNUNET_PeerIdentity *key,
784 struct MeshTunnel3 *t = value;
785 struct GNUNET_TIME_Relative delay;
789 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
792 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
793 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
794 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
801 * Create a new ephemeral key and key message, schedule next rekeying.
803 * @param cls Closure (unused).
804 * @param tc TaskContext.
807 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
809 struct GNUNET_TIME_Absolute time;
812 rekey_task = GNUNET_SCHEDULER_NO_TASK;
814 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
817 GNUNET_free_non_null (my_ephemeral_key);
818 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
820 time = GNUNET_TIME_absolute_get ();
821 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
822 time = GNUNET_TIME_absolute_add (time, rekey_period);
823 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
824 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
825 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
827 GNUNET_assert (GNUNET_OK ==
828 GNUNET_CRYPTO_eddsa_sign (my_private_key,
832 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
833 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
835 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
840 * Demultiplex data per channel and call appropriate channel handler.
842 * @param t Tunnel on which the data came.
843 * @param msg Data message.
844 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
845 * #GNUNET_YES if message is FWD on the respective channel (loopback)
846 * #GNUNET_NO if message is BCK on the respective channel (loopback)
847 * #GNUNET_SYSERR if message on a one-ended channel (remote)
850 handle_data (struct MeshTunnel3 *t,
851 const struct GNUNET_MESH_Data *msg,
854 struct MeshChannel *ch;
859 size = ntohs (msg->header.size);
861 sizeof (struct GNUNET_MESH_Data) +
862 sizeof (struct GNUNET_MessageHeader))
867 type = ntohs (msg->header.type);
868 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message\n",
869 GNUNET_MESH_DEBUG_M2S (type));
870 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
871 GNUNET_MESH_DEBUG_M2S (ntohs (msg[1].header.type)));
874 ch = GMT_get_channel (t, ntohl (msg->chid));
877 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
879 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
884 GMT_change_state (t, MESH_TUNNEL3_READY);
885 GMCH_handle_data (ch, msg, fwd);
890 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
892 * @param t Tunnel on which the DATA ACK came.
893 * @param msg DATA ACK message.
894 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
895 * #GNUNET_YES if message is FWD on the respective channel (loopback)
896 * #GNUNET_NO if message is BCK on the respective channel (loopback)
897 * #GNUNET_SYSERR if message on a one-ended channel (remote)
900 handle_data_ack (struct MeshTunnel3 *t,
901 const struct GNUNET_MESH_DataACK *msg,
904 struct MeshChannel *ch;
908 size = ntohs (msg->header.size);
909 if (size != sizeof (struct GNUNET_MESH_DataACK))
916 ch = GMT_get_channel (t, ntohl (msg->chid));
919 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
921 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
926 GMCH_handle_data_ack (ch, msg, fwd);
931 * Handle channel create.
933 * @param t Tunnel on which the data came.
934 * @param msg Data message.
937 handle_ch_create (struct MeshTunnel3 *t,
938 const struct GNUNET_MESH_ChannelCreate *msg)
940 struct MeshChannel *ch;
944 size = ntohs (msg->header.size);
945 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
952 ch = GMT_get_channel (t, ntohl (msg->chid));
953 if (NULL != ch && ! GMT_is_loopback (t))
955 /* Probably a retransmission, safe to ignore */
956 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
960 ch = GMCH_handle_create (t, msg);
963 GMT_add_channel (t, ch);
969 * Handle channel NACK.
971 * @param t Tunnel on which the data came.
972 * @param msg Data message.
975 handle_ch_nack (struct MeshTunnel3 *t,
976 const struct GNUNET_MESH_ChannelManage *msg)
978 struct MeshChannel *ch;
982 size = ntohs (msg->header.size);
983 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
990 ch = GMT_get_channel (t, ntohl (msg->chid));
991 if (NULL != ch && ! GMT_is_loopback (t))
993 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
995 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1000 GMCH_handle_nack (ch);
1005 * Handle a CHANNEL ACK (SYNACK/ACK).
1007 * @param t Tunnel on which the CHANNEL ACK came.
1008 * @param msg CHANNEL ACK message.
1009 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1010 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1011 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1012 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1015 handle_ch_ack (struct MeshTunnel3 *t,
1016 const struct GNUNET_MESH_ChannelManage *msg,
1019 struct MeshChannel *ch;
1023 size = ntohs (msg->header.size);
1024 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1031 ch = GMT_get_channel (t, ntohl (msg->chid));
1034 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1036 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1041 GMCH_handle_ack (ch, msg, fwd);
1047 * Handle a channel destruction message.
1049 * @param t Tunnel on which the message came.
1050 * @param msg Channel destroy message.
1051 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1052 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1053 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1054 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1057 handle_ch_destroy (struct MeshTunnel3 *t,
1058 const struct GNUNET_MESH_ChannelManage *msg,
1061 struct MeshChannel *ch;
1065 size = ntohs (msg->header.size);
1066 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1073 ch = GMT_get_channel (t, ntohl (msg->chid));
1076 /* Probably a retransmission, safe to ignore */
1080 GMCH_handle_destroy (ch, msg, fwd);
1085 * The peer's ephemeral key has changed: update the symmetrical keys.
1087 * @param t Tunnel this message came on.
1088 * @param msg Key eXchange message.
1091 handle_ephemeral (struct MeshTunnel3 *t,
1092 const struct GNUNET_MESH_KX_Ephemeral *msg)
1094 struct GNUNET_HashCode km;
1095 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1097 if (GNUNET_OK != check_ephemeral (t, msg))
1099 GNUNET_break_op (0);
1102 derive_key_material (&km, &msg->ephemeral_key);
1103 LOG (GNUNET_ERROR_TYPE_DEBUG, " km is %s\n", GNUNET_h2s (&km));
1104 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1105 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1106 if (MESH_TUNNEL3_KEY_SENT == t->state)
1108 LOG (GNUNET_ERROR_TYPE_DEBUG, " our key was sent, send ping\n");
1110 t->state = MESH_TUNNEL3_REKEY;
1116 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1117 * Answer with by retransmitting the challenge with the "opposite" key.
1119 * @param t Tunnel this message came on.
1120 * @param msg Key eXchange Ping message.
1123 handle_ping (struct MeshTunnel3 *t,
1124 const struct GNUNET_MESH_KX_Ping *msg)
1126 struct GNUNET_MESH_KX_Ping res;
1128 if (ntohs (msg->header.size) != sizeof (res))
1130 GNUNET_break_op (0);
1134 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1135 t_decrypt (t, &res.target, &msg->target, ping_encryption_size (), msg->iv);
1136 if (0 != memcmp (&my_full_id, &res.target, sizeof (my_full_id)))
1139 LOG (GNUNET_ERROR_TYPE_DEBUG, " e got %u\n", msg->nonce);
1140 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg->target));
1141 LOG (GNUNET_ERROR_TYPE_DEBUG, " got %u\n", res.nonce);
1142 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&res.target));
1146 send_pong (t, res.nonce);
1151 * Peer has answer to our challenge.
1152 * If answer is successful, consider the key exchange finished and clean
1153 * up all related state.
1155 * @param t Tunnel this message came on.
1156 * @param msg Key eXchange Pong message.
1159 handle_pong (struct MeshTunnel3 *t,
1160 const struct GNUNET_MESH_KX_Pong *msg)
1164 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1165 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1167 GNUNET_break_op (0);
1170 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1172 if (challenge != t->kx_ctx->challenge)
1174 LOG (GNUNET_ERROR_TYPE_DEBUG,
1175 "Wrong PONG challenge: %u (e: %u). Expected: %u.\n",
1176 challenge, msg->nonce, t->kx_ctx->challenge);
1177 GNUNET_break_op (0);
1180 GNUNET_SCHEDULER_cancel (t->rekey_task);
1181 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1182 GNUNET_free (t->kx_ctx);
1184 t->state = MESH_TUNNEL3_READY;
1185 send_queued_data (t);
1190 * Demultiplex by message type and call appropriate handler for a message
1191 * towards a channel of a local tunnel.
1193 * @param t Tunnel this message came on.
1194 * @param msgh Message header.
1195 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1196 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1197 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1198 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1201 handle_decrypted (struct MeshTunnel3 *t,
1202 const struct GNUNET_MessageHeader *msgh,
1207 type = ntohs (msgh->type);
1208 LOG (GNUNET_ERROR_TYPE_DEBUG,
1209 "Got a %s message!\n",
1210 GNUNET_MESH_DEBUG_M2S (type));
1214 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1215 /* Don't send hop ACK, wait for client to ACK */
1216 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1219 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1220 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1223 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1224 handle_ch_create (t,
1225 (struct GNUNET_MESH_ChannelCreate *) msgh);
1228 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1230 (struct GNUNET_MESH_ChannelManage *) msgh);
1233 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1235 (struct GNUNET_MESH_ChannelManage *) msgh,
1239 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1240 handle_ch_destroy (t,
1241 (struct GNUNET_MESH_ChannelManage *) msgh,
1246 GNUNET_break_op (0);
1247 LOG (GNUNET_ERROR_TYPE_DEBUG,
1248 "end-to-end message not known (%u)\n",
1249 ntohs (msgh->type));
1253 /******************************************************************************/
1254 /******************************** API ***********************************/
1255 /******************************************************************************/
1258 * Decrypt and demultiplex by message type. Call appropriate handler
1259 * for every message.
1261 * @param t Tunnel this message came on.
1262 * @param msg Encrypted message.
1265 GMT_handle_encrypted (struct MeshTunnel3 *t,
1266 const struct GNUNET_MESH_Encrypted *msg)
1268 size_t size = ntohs (msg->header.size);
1269 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1270 size_t decrypted_size;
1271 char cbuf [payload_size];
1272 struct GNUNET_MessageHeader *msgh;
1275 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1277 while (off < decrypted_size)
1279 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1280 handle_decrypted (t, msgh, GNUNET_SYSERR);
1281 off += ntohs (msgh->size);
1287 * Demultiplex an encapsulated KX message by message type.
1289 * @param t Tunnel on which the message came.
1290 * @param message Payload of KX message.
1293 GMT_handle_kx (struct MeshTunnel3 *t,
1294 const struct GNUNET_MessageHeader *message)
1298 type = ntohs (message->type);
1299 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1302 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1303 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1306 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1307 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1310 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1311 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1315 GNUNET_break_op (0);
1316 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1322 * Initialize the tunnel subsystem.
1324 * @param c Configuration handle.
1325 * @param key ECC private key, to derive all other keys and do crypto.
1328 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1329 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1331 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1333 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1336 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1337 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1341 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1344 rekey_period = GNUNET_TIME_UNIT_DAYS;
1347 my_private_key = key;
1348 kx_msg.header.size = htons (sizeof (kx_msg));
1349 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1350 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1351 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1352 kx_msg.origin_identity = my_full_id;
1353 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1355 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1360 * Shut down the tunnel subsystem.
1365 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1367 GNUNET_SCHEDULER_cancel (rekey_task);
1368 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1370 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1377 * @param destination Peer this tunnel is towards.
1379 struct MeshTunnel3 *
1380 GMT_new (struct MeshPeer *destination)
1382 struct MeshTunnel3 *t;
1384 t = GNUNET_new (struct MeshTunnel3);
1386 t->peer = destination;
1389 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1390 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1401 * Change the tunnel state.
1403 * @param t Tunnel whose state to change.
1404 * @param state New state.
1407 GMT_change_state (struct MeshTunnel3* t, enum MeshTunnel3State state)
1411 LOG (GNUNET_ERROR_TYPE_DEBUG,
1412 "Tunnel %s state was %s\n",
1414 GMT_state2s (t->state));
1415 LOG (GNUNET_ERROR_TYPE_DEBUG,
1416 "Tunnel %s state is now %s\n",
1418 GMT_state2s (state));
1419 if (myid != GMP_get_short_id (t->peer) &&
1420 MESH_TUNNEL3_WAITING == t->state && MESH_TUNNEL3_READY == state)
1422 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1423 rekey_tunnel (t, NULL);
1424 LOG (GNUNET_ERROR_TYPE_DEBUG,
1425 "Tunnel %s state is now %s\n",
1427 GMT_state2s (t->state));
1433 if (MESH_TUNNEL3_READY == state && 3 <= GMT_count_connections (t))
1435 GMP_stop_search (t->peer);
1441 * Add a connection to a tunnel.
1444 * @param c Connection.
1447 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1449 struct MeshTConnection *aux;
1451 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1455 aux = GNUNET_new (struct MeshTConnection);
1457 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1462 * Remove a connection from a tunnel.
1465 * @param c Connection.
1468 GMT_remove_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1470 struct MeshTConnection *aux;
1472 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1475 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1483 * Add a channel to a tunnel.
1486 * @param ch Channel.
1489 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1491 struct MeshTChannel *aux;
1493 GNUNET_assert (NULL != ch);
1495 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1497 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1499 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1504 aux = GNUNET_new (struct MeshTChannel);
1506 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1507 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1512 * Remove a channel from a tunnel.
1515 * @param ch Channel.
1518 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1520 struct MeshTChannel *aux;
1522 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1523 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1527 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1528 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1537 * Search for a channel by global ID.
1539 * @param t Tunnel containing the channel.
1540 * @param chid Public channel number.
1542 * @return channel handler, NULL if doesn't exist
1544 struct MeshChannel *
1545 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1547 struct MeshTChannel *iter;
1552 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1554 if (GMCH_get_id (iter->ch) == chid)
1558 return NULL == iter ? NULL : iter->ch;
1563 * Tunnel is empty: destroy it.
1565 * Notifies all connections about the destruction.
1567 * @param t Tunnel to destroy.
1570 GMT_destroy_empty (struct MeshTunnel3 *t)
1572 struct MeshTConnection *iter;
1574 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1576 GMC_send_destroy (iter->c);
1579 t->destroy = GNUNET_YES;
1584 * Destroy tunnel if empty (no more channels).
1586 * @param t Tunnel to destroy if empty.
1589 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1591 if (1 < GMT_count_channels (t))
1594 GMT_destroy_empty (t);
1599 * Destroy the tunnel.
1601 * This function does not generate any warning traffic to clients or peers.
1604 * Cancel messages belonging to this tunnel queued to neighbors.
1605 * Free any allocated resources linked to the tunnel.
1607 * @param t The tunnel to destroy.
1610 GMT_destroy (struct MeshTunnel3 *t)
1612 struct MeshTConnection *iter;
1613 struct MeshTConnection *next;
1618 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
1620 // if (GNUNET_YES != GNUNET_CONTAINER_multihashmap_remove (tunnels, &t->id, t))
1621 // GNUNET_break (0);
1623 for (iter = t->connection_head; NULL != iter; iter = next)
1626 GMC_destroy (iter->c);
1629 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
1630 GMP_set_tunnel (t->peer, NULL);
1632 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1633 GNUNET_SCHEDULER_cancel (t->rekey_task);
1640 * @brief Use the given path for the tunnel.
1641 * Update the next and prev hops (and RCs).
1642 * (Re)start the path refresh in case the tunnel is locally owned.
1644 * @param t Tunnel to update.
1645 * @param p Path to use.
1647 * @return Connection created.
1649 struct MeshConnection *
1650 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
1652 struct MeshConnection *c;
1653 struct GNUNET_HashCode cid;
1654 unsigned int own_pos;
1656 if (NULL == t || NULL == p)
1662 for (own_pos = 0; own_pos < p->length; own_pos++)
1664 if (p->peers[own_pos] == myid)
1667 if (own_pos > p->length - 1)
1673 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
1674 c = GMC_new (&cid, t, p, own_pos);
1675 GMT_add_connection (t, c);
1681 * Count established (ready) connections of a tunnel.
1683 * @param t Tunnel on which to count.
1685 * @return Number of connections.
1688 GMT_count_connections (struct MeshTunnel3 *t)
1690 struct MeshTConnection *iter;
1693 for (count = 0, iter = t->connection_head;
1695 iter = iter->next, count++);
1701 * Count channels of a tunnel.
1703 * @param t Tunnel on which to count.
1705 * @return Number of channels.
1708 GMT_count_channels (struct MeshTunnel3 *t)
1710 struct MeshTChannel *iter;
1713 for (count = 0, iter = t->channel_head;
1715 iter = iter->next, count++) /* skip */;
1722 * Get the state of a tunnel.
1726 * @return Tunnel's state.
1728 enum MeshTunnel3State
1729 GMT_get_state (struct MeshTunnel3 *t)
1734 return (enum MeshTunnel3State) -1;
1741 * Get the maximum buffer space for a tunnel towards a local client.
1745 * @return Biggest buffer space offered by any channel in the tunnel.
1748 GMT_get_channels_buffer (struct MeshTunnel3 *t)
1750 struct MeshTChannel *iter;
1751 unsigned int buffer;
1752 unsigned int ch_buf;
1754 if (NULL == t->channel_head)
1756 /* Probably getting buffer for a channel create/handshake. */
1761 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1763 ch_buf = get_channel_buffer (iter);
1764 if (ch_buf > buffer)
1772 * Get the total buffer space for a tunnel for P2P traffic.
1776 * @return Buffer space offered by all connections in the tunnel.
1779 GMT_get_connections_buffer (struct MeshTunnel3 *t)
1781 struct MeshTConnection *iter;
1782 unsigned int buffer;
1784 iter = t->connection_head;
1786 while (NULL != iter)
1788 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
1794 buffer += get_connection_buffer (iter);
1803 * Get the tunnel's destination.
1807 * @return ID of the destination peer.
1809 const struct GNUNET_PeerIdentity *
1810 GMT_get_destination (struct MeshTunnel3 *t)
1812 return GMP_get_id (t->peer);
1817 * Get the tunnel's next free global channel ID.
1821 * @return GID of a channel free to use.
1824 GMT_get_next_chid (struct MeshTunnel3 *t)
1826 MESH_ChannelNumber chid;
1828 while (NULL != GMT_get_channel (t, t->next_chid))
1830 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
1831 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
1833 chid = t->next_chid;
1834 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
1841 * Send ACK on one or more channels due to buffer in connections.
1843 * @param t Channel which has some free buffer space.
1846 GMT_unchoke_channels (struct MeshTunnel3 *t)
1848 struct MeshTChannel *iter;
1849 unsigned int buffer;
1850 unsigned int channels = GMT_count_channels (t);
1851 unsigned int choked_n;
1852 struct MeshChannel *choked[channels];
1854 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
1855 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
1856 if (NULL != t->channel_head)
1857 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
1865 /* Get buffer space */
1866 buffer = GMT_get_connections_buffer (t);
1872 /* Count and remember choked channels */
1874 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1876 if (GNUNET_NO == get_channel_allowed (iter))
1878 choked[choked_n++] = iter->ch;
1882 /* Unchoke random channels */
1883 while (0 < buffer && 0 < choked_n)
1885 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1887 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
1890 choked[r] = choked[choked_n];
1896 * Send ACK on one or more connections due to buffer space to the client.
1898 * Iterates all connections of the tunnel and sends ACKs appropriately.
1903 GMT_send_connection_acks (struct MeshTunnel3 *t)
1905 struct MeshTConnection *iter;
1908 uint32_t allow_per_connection;
1910 unsigned int buffer;
1912 LOG (GNUNET_ERROR_TYPE_DEBUG,
1913 "Tunnel send connection ACKs on %s\n",
1922 buffer = GMT_get_channels_buffer (t);
1924 /* Count connections, how many messages are already allowed */
1925 cs = GMT_count_connections (t);
1926 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
1928 allowed += get_connection_allowed (iter);
1931 /* Make sure there is no overflow */
1932 if (allowed > buffer)
1937 /* Authorize connections to send more data */
1938 to_allow = buffer; /* - allowed; */
1940 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
1942 allow_per_connection = to_allow/cs;
1943 to_allow -= allow_per_connection;
1945 if (get_connection_allowed (iter) > 64 / 3)
1949 GMC_allow (iter->c, buffer, GMC_is_origin (iter->c, GNUNET_YES));
1952 GNUNET_break (to_allow == 0);
1957 * Sends an already built message on a tunnel, encrypting it and
1958 * choosing the best connection.
1960 * @param message Message to send. Function modifies it.
1961 * @param t Tunnel on which this message is transmitted.
1962 * @param ch Channel on which this message is transmitted.
1963 * @param fwd Is this a fwd message on @c ch?
1966 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
1967 struct MeshTunnel3 *t,
1968 struct MeshChannel *ch,
1971 struct MeshConnection *c;
1972 struct GNUNET_MESH_Encrypted *msg;
1973 size_t size = ntohs (message->size);
1974 size_t encrypted_size;
1975 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
1979 if (MESH_TUNNEL3_READY != t->state)
1981 queue_data (t, ch, message);
1984 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
1986 if (GMT_is_loopback (t))
1988 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
1989 handle_decrypted (t, message, fwd);
1993 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
1994 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
1995 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
1997 encrypted_size = t_encrypt (t, &msg[1], message, size, iv);
1998 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + encrypted_size);
1999 c = tunnel_get_connection (t);
2002 GNUNET_break (GNUNET_YES == t->destroy);
2005 type = ntohs (message->type);
2008 case GNUNET_MESSAGE_TYPE_MESH_DATA:
2009 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
2010 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
2011 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
2012 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
2013 msg->cid = *GMC_get_id (c);
2014 msg->ttl = htonl (default_ttl);
2017 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
2018 GNUNET_MESH_DEBUG_M2S (type));
2022 fwd = GMC_is_origin (c, GNUNET_YES);
2023 /* FIXME allow channels to cancel */
2024 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
2028 * Is the tunnel directed towards the local peer?
2032 * @return #GNUNET_YES if it is loopback.
2035 GMT_is_loopback (const struct MeshTunnel3 *t)
2037 return (myid == GMP_get_short_id (t->peer));
2042 * Is the tunnel this path already?
2047 * @return #GNUNET_YES a connection uses this path.
2050 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2052 struct MeshTConnection *iter;
2054 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2055 if (GMC_get_path (iter->c) == p)
2063 * Get a cost of a path for a tunnel considering existing connections.
2066 * @param path Candidate path.
2068 * @return Cost of the path (path length + number of overlapping nodes)
2071 GMT_get_path_cost (const struct MeshTunnel3 *t,
2072 const struct MeshPeerPath *path)
2074 struct MeshTConnection *iter;
2075 unsigned int overlap;
2083 GNUNET_assert (NULL != t);
2085 for (i = 0; i < path->length; i++)
2087 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2089 for (j = 0; j < GMC_get_path (iter->c)->length; j++)
2091 if (path->peers[i] == GMC_get_path (iter->c)->peers[j])
2099 return (path->length + overlap) * (path->score * -1);
2104 * Get the static string for the peer this tunnel is directed.
2108 * @return Static string the destination peer's ID.
2111 GMT_2s (const struct MeshTunnel3 *t)
2116 return GMP_2s (t->peer);