2 This file is part of GNUnet.
3 (C) 2013 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 #include "gnunet_util_lib.h"
24 #include "gnunet_signatures.h"
25 #include "gnunet_statistics_service.h"
27 #include "mesh_protocol_enc.h"
28 #include "mesh_path.h"
30 #include "gnunet-service-mesh_tunnel.h"
31 #include "gnunet-service-mesh_connection.h"
32 #include "gnunet-service-mesh_channel.h"
33 #include "gnunet-service-mesh_peer.h"
35 #define LOG(level, ...) GNUNET_log_from(level,"mesh-tun",__VA_ARGS__)
37 #define REKEY_WAIT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 30)
39 /******************************************************************************/
40 /******************************** STRUCTS **********************************/
41 /******************************************************************************/
45 struct MeshTChannel *next;
46 struct MeshTChannel *prev;
47 struct MeshChannel *ch;
50 struct MeshTConnection
52 struct MeshTConnection *next;
53 struct MeshTConnection *prev;
54 struct MeshConnection *c;
58 * Structure used during a Key eXchange.
60 struct MeshTunnelKXCtx
63 * Decryption ("their") old key, for decrypting traffic sent by the
64 * other end before the key exchange started.
66 struct GNUNET_CRYPTO_SymmetricSessionKey d_key_old;
69 * Challenge to send in a ping and expect in the pong.
75 * Struct containing all information regarding a tunnel to a peer.
80 * Endpoint of the tunnel.
82 struct MeshPeer *peer;
85 * State of the tunnel.
87 enum MeshTunnel3State state;
90 * Key eXchange context.
92 struct MeshTunnelKXCtx *kx_ctx;
95 * Encryption ("our") key.
97 struct GNUNET_CRYPTO_SymmetricSessionKey e_key;
100 * Decryption ("their") key.
102 struct GNUNET_CRYPTO_SymmetricSessionKey d_key;
105 * Task to start the rekey process.
107 GNUNET_SCHEDULER_TaskIdentifier rekey_task;
110 * Paths that are actively used to reach the destination peer.
112 struct MeshTConnection *connection_head;
113 struct MeshTConnection *connection_tail;
116 * Next connection number.
121 * Channels inside this tunnel.
123 struct MeshTChannel *channel_head;
124 struct MeshTChannel *channel_tail;
127 * Channel ID for the next created channel.
129 MESH_ChannelNumber next_chid;
132 * Destroy flag: if true, destroy on last message.
137 * Queued messages, to transmit once tunnel gets connected.
139 struct MeshTunnelQueue *tq_head;
140 struct MeshTunnelQueue *tq_tail;
145 * Struct used to queue messages in a tunnel.
147 struct MeshTunnelQueue
152 struct MeshTunnelQueue *next;
153 struct MeshTunnelQueue *prev;
158 struct MeshChannel *ch;
163 /* struct GNUNET_MessageHeader *msg; */
167 /******************************************************************************/
168 /******************************* GLOBALS ***********************************/
169 /******************************************************************************/
172 * Global handle to the statistics service.
174 extern struct GNUNET_STATISTICS_Handle *stats;
177 * Local peer own ID (memory efficient handle).
179 extern GNUNET_PEER_Id myid;
182 * Local peer own ID (full value).
184 extern struct GNUNET_PeerIdentity my_full_id;
188 * Set of all tunnels, in order to trigger a new exchange on rekey.
189 * Indexed by peer's ID.
191 static struct GNUNET_CONTAINER_MultiPeerMap *tunnels;
194 * Default TTL for payload packets.
196 static unsigned long long default_ttl;
201 const static struct GNUNET_CRYPTO_EddsaPrivateKey *my_private_key;
204 * Own ephemeral private key.
206 static struct GNUNET_CRYPTO_EcdhePrivateKey *my_ephemeral_key;
209 * Cached message used to perform a key exchange.
211 static struct GNUNET_MESH_KX_Ephemeral kx_msg;
214 * Task to generate a new ephemeral key.
216 static GNUNET_SCHEDULER_TaskIdentifier rekey_task;
221 static struct GNUNET_TIME_Relative rekey_period;
223 /******************************************************************************/
224 /******************************** STATIC ***********************************/
225 /******************************************************************************/
228 * Get string description for tunnel state.
230 * @param s Tunnel state.
232 * @return String representation.
235 GMT_state2s (enum MeshTunnel3State s)
237 static char buf[128];
241 case MESH_TUNNEL3_NEW:
242 return "MESH_TUNNEL3_NEW";
243 case MESH_TUNNEL3_SEARCHING:
244 return "MESH_TUNNEL3_SEARCHING";
245 case MESH_TUNNEL3_WAITING:
246 return "MESH_TUNNEL3_WAITING";
247 case MESH_TUNNEL3_KEY_SENT:
248 return "MESH_TUNNEL3_KEY_SENT";
249 case MESH_TUNNEL3_PING_SENT:
250 return "MESH_TUNNEL3_PING_SENT";
251 case MESH_TUNNEL3_READY:
252 return "MESH_TUNNEL3_READY";
253 case MESH_TUNNEL3_RECONNECTING:
254 return "MESH_TUNNEL3_RECONNECTING";
255 case MESH_TUNNEL3_REKEY:
256 return "MESH_TUNNEL3_REKEY";
259 sprintf (buf, "%u (UNKNOWN STATE)", s);
266 * Ephemeral key message purpose size.
268 * @return Size of the part of the ephemeral key message that must be signed.
271 ephemeral_purpose_size (void)
273 return sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
274 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
275 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
276 sizeof (struct GNUNET_CRYPTO_EcdhePublicKey) +
277 sizeof (struct GNUNET_PeerIdentity);
282 * Size of the encrypted part of a ping message.
284 * @return Size of the encrypted part of a ping message.
287 ping_encryption_size (void)
289 return sizeof (struct GNUNET_PeerIdentity) + sizeof (uint32_t);
294 * Get the channel's buffer. ONLY FOR NON-LOOPBACK CHANNELS!!
296 * @param tch Tunnel's channel handle.
298 * @return Amount of messages the channel can still buffer towards the client.
301 get_channel_buffer (const struct MeshTChannel *tch)
305 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
306 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
308 return GMCH_get_buffer (tch->ch, fwd);
313 * Get the channel's allowance status.
315 * @param tch Tunnel's channel handle.
317 * @return #GNUNET_YES if we allowed the client to send data to us.
320 get_channel_allowed (const struct MeshTChannel *tch)
324 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
325 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
327 return GMCH_get_allowed (tch->ch, fwd);
332 * Get the connection's buffer.
334 * @param tc Tunnel's connection handle.
336 * @return Amount of messages the connection can still buffer.
339 get_connection_buffer (const struct MeshTConnection *tc)
343 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
344 fwd = GMC_is_origin (tc->c, GNUNET_YES);
346 return GMC_get_buffer (tc->c, fwd);
351 * Get the connection's allowance.
353 * @param tc Tunnel's connection handle.
355 * @return Amount of messages we have allowed the next peer to send us.
358 get_connection_allowed (const struct MeshTConnection *tc)
362 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
363 fwd = GMC_is_origin (tc->c, GNUNET_YES);
365 return GMC_get_allowed (tc->c, fwd);
370 * Check that a ephemeral key message s well formed and correctly signed.
372 * @param t Tunnel on which the message came.
373 * @param msg The ephemeral key message.
375 * @return GNUNET_OK if message is fine, GNUNET_SYSERR otherwise.
378 check_ephemeral (struct MeshTunnel3 *t,
379 const struct GNUNET_MESH_KX_Ephemeral *msg)
381 /* Check message size */
382 if (ntohs (msg->header.size) != sizeof (struct GNUNET_MESH_KX_Ephemeral))
383 return GNUNET_SYSERR;
385 /* Check signature size */
386 if (ntohl (msg->purpose.size) != ephemeral_purpose_size ())
387 return GNUNET_SYSERR;
390 if (0 != memcmp (&msg->origin_identity,
391 GMP_get_id (t->peer),
392 sizeof (struct GNUNET_PeerIdentity)))
393 return GNUNET_SYSERR;
395 /* Check signature */
397 GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_MESH_KX,
400 &msg->origin_identity.public_key))
401 return GNUNET_SYSERR;
408 * Encrypt data with the tunnel key.
410 * @param t Tunnel whose key to use.
411 * @param dst Destination for the encrypted data.
412 * @param src Source of the plaintext. Can overlap with @c dst.
413 * @param size Size of the plaintext.
414 * @param iv Initialization Vector to use.
417 t_encrypt (struct MeshTunnel3 *t,
418 void *dst, const void *src,
419 size_t size, uint32_t iv)
421 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
423 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->e_key, &iv, sizeof (uint32_t), NULL);
424 return GNUNET_CRYPTO_symmetric_encrypt (src, size, &t->e_key, &siv, dst);
429 * Decrypt data with the tunnel key.
431 * @param t Tunnel whose key to use.
432 * @param dst Destination for the plaintext.
433 * @param src Source of the encrypted data. Can overlap with @c dst.
434 * @param size Size of the encrypted data.
435 * @param iv Initialization Vector to use.
438 t_decrypt (struct MeshTunnel3 *t,
439 void *dst, const void *src,
440 size_t size, uint32_t iv)
442 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
444 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->d_key, &iv, sizeof (uint32_t), NULL);
445 return GNUNET_CRYPTO_symmetric_decrypt (src, size, &t->d_key, &siv, dst);
450 * Create key material by doing ECDH on the local and remote ephemeral keys.
452 * @param key_material Where to store the key material.
453 * @param ephemeral_key Peer's public ephemeral key.
456 derive_key_material (struct GNUNET_HashCode *key_material,
457 const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key)
460 GNUNET_CRYPTO_ecc_ecdh (my_ephemeral_key,
469 * Create a symmetic key from the identities of both ends and the key material
472 * @param key Destination for the generated key.
473 * @param sender ID of the peer that will encrypt with @c key.
474 * @param receiver ID of the peer that will decrypt with @c key.
475 * @param key_material Hash created with ECDH with the ephemeral keys.
478 derive_symmertic (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
479 const struct GNUNET_PeerIdentity *sender,
480 const struct GNUNET_PeerIdentity *receiver,
481 const struct GNUNET_HashCode *key_material)
483 const char salt[] = "MESH kx salt";
485 GNUNET_CRYPTO_kdf (key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
487 key_material, sizeof (struct GNUNET_HashCode),
488 sender, sizeof (struct GNUNET_PeerIdentity),
489 receiver, sizeof (struct GNUNET_PeerIdentity),
494 * Pick a connection on which send the next data message.
496 * @param t Tunnel on which to send the message.
498 * @return The connection on which to send the next message.
500 static struct MeshConnection *
501 tunnel_get_connection (struct MeshTunnel3 *t)
503 struct MeshTConnection *iter;
504 struct MeshConnection *best;
506 unsigned int lowest_q;
508 LOG (GNUNET_ERROR_TYPE_DEBUG, "tunnel_get_connection %s\n", GMP_2s (t->peer));
511 for (iter = t->connection_head; NULL != iter; iter = iter->next)
513 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s: %u\n",
514 GNUNET_h2s (GMC_get_id (iter->c)), GMC_get_state (iter->c));
515 if (MESH_CONNECTION_READY == GMC_get_state (iter->c))
517 qn = GMC_get_qn (iter->c, GMC_is_origin (iter->c, GNUNET_YES));
518 LOG (GNUNET_ERROR_TYPE_DEBUG, " q_n %u, \n", qn);
531 * Send all cached messages that we can, tunnel is online.
533 * @param t Tunnel that holds the messages. Cannot be loopback.
536 send_queued_data (struct MeshTunnel3 *t)
538 struct MeshTunnelQueue *tq;
539 struct MeshTunnelQueue *next;
542 LOG (GNUNET_ERROR_TYPE_DEBUG,
543 "GMT_send_queued_data on tunnel %s\n",
546 if (GMT_is_loopback (t))
552 room = GMT_get_connections_buffer (t);
553 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
554 for (tq = t->tq_head; NULL != tq && room > 0; tq = next)
556 LOG (GNUNET_ERROR_TYPE_DEBUG, " data on channel %s\n", GMCH_2s (tq->ch));
559 GNUNET_CONTAINER_DLL_remove (t->tq_head, t->tq_tail, tq);
560 GMCH_send_prebuilt_message ((struct GNUNET_MessageHeader *) &tq[1],
561 tq->ch, GMCH_is_origin (tq->ch, GNUNET_YES));
565 LOG (GNUNET_ERROR_TYPE_DEBUG,
566 "GMT_send_queued_data end\n",
574 * Cache a message to be sent once tunnel is online.
576 * @param t Tunnel to hold the message.
577 * @param ch Channel the message is about.
578 * @param msg Message itself (copy will be made).
581 queue_data (struct MeshTunnel3 *t,
582 struct MeshChannel *ch,
583 const struct GNUNET_MessageHeader *msg)
585 struct MeshTunnelQueue *tq;
586 uint16_t size = ntohs (msg->size);
588 if (MESH_TUNNEL3_READY == t->state)
594 tq = GNUNET_malloc (sizeof (struct MeshTunnelQueue) + size);
597 memcpy (&tq[1], msg, size);
598 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tq);
604 * Sends key exchange message on a tunnel, choosing the best connection.
605 * Should not be called on loopback tunnels.
607 * @param t Tunnel on which this message is transmitted.
608 * @param message Message to send. Function modifies it.
611 send_kx (struct MeshTunnel3 *t,
612 const struct GNUNET_MessageHeader *message)
614 struct MeshConnection *c;
615 struct GNUNET_MESH_KX *msg;
616 size_t size = ntohs (message->size);
617 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
621 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
623 /* Avoid loopback. */
624 if (GMT_is_loopback (t))
626 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
631 /* Must have a connection. */
632 if (NULL == t->connection_head)
638 msg = (struct GNUNET_MESH_KX *) cbuf;
639 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
640 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
641 c = tunnel_get_connection (t);
644 GNUNET_break (GNUNET_YES == t->destroy);
647 type = ntohs (message->type);
650 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
651 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
652 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
653 msg->reserved = htonl (0);
654 memcpy (&msg[1], message, size);
657 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
658 GNUNET_MESH_DEBUG_M2S (type));
662 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
663 GMC_send_prebuilt_message (&msg->header, c, fwd);
668 * Send the ephemeral key on a tunnel.
670 * @param t Tunnel on which to send the key.
673 send_ephemeral (struct MeshTunnel3 *t)
675 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
677 kx_msg.sender_status = htonl (t->state);
678 send_kx (t, &kx_msg.header);
682 * Send a ping message on a tunnel.
684 * @param t Tunnel on which to send the ping.
687 send_ping (struct MeshTunnel3 *t)
689 struct GNUNET_MESH_KX_Ping msg;
691 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
692 msg.header.size = htons (sizeof (msg));
693 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
694 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
695 msg.target = *GMP_get_id (t->peer);
696 msg.nonce = t->kx_ctx->challenge;
698 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
699 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&msg.target));
700 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
701 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
702 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg.target));
704 send_kx (t, &msg.header);
709 * Send a pong message on a tunnel.
711 * @param t Tunnel on which to send the pong.
712 * @param challenge Value sent in the ping that we have to send back.
715 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
717 struct GNUNET_MESH_KX_Pong msg;
719 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
720 msg.header.size = htons (sizeof (msg));
721 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
722 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
723 msg.nonce = challenge;
724 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
725 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
726 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
728 send_kx (t, &msg.header);
733 * Initiate a rekey with the remote peer.
735 * @param cls Closure (tunnel).
736 * @param tc TaskContext.
739 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
741 struct MeshTunnel3 *t = cls;
743 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
745 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
748 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
749 t->kx_ctx->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
751 t->kx_ctx->d_key_old = t->d_key;
753 if (MESH_TUNNEL3_READY == t->state)
756 t->state = MESH_TUNNEL3_REKEY;
758 else if (MESH_TUNNEL3_WAITING == t->state)
760 t->state = MESH_TUNNEL3_KEY_SENT;
764 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->state);
767 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
772 * Out ephemeral key has changed, create new session key on all tunnels.
774 * @param cls Closure (size of the hashmap).
775 * @param key Current public key.
776 * @param value Value in the hash map (tunnel).
778 * @return #GNUNET_YES, so we should continue to iterate,
781 rekey_iterator (void *cls,
782 const struct GNUNET_PeerIdentity *key,
785 struct MeshTunnel3 *t = value;
786 struct GNUNET_TIME_Relative delay;
790 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
793 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
794 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
795 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
802 * Create a new ephemeral key and key message, schedule next rekeying.
804 * @param cls Closure (unused).
805 * @param tc TaskContext.
808 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
810 struct GNUNET_TIME_Absolute time;
813 rekey_task = GNUNET_SCHEDULER_NO_TASK;
815 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
818 GNUNET_free_non_null (my_ephemeral_key);
819 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
821 time = GNUNET_TIME_absolute_get ();
822 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
823 time = GNUNET_TIME_absolute_add (time, rekey_period);
824 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
825 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
826 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
828 GNUNET_assert (GNUNET_OK ==
829 GNUNET_CRYPTO_eddsa_sign (my_private_key,
833 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
834 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
836 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
841 * Demultiplex data per channel and call appropriate channel handler.
843 * @param t Tunnel on which the data came.
844 * @param msg Data message.
845 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
846 * #GNUNET_YES if message is FWD on the respective channel (loopback)
847 * #GNUNET_NO if message is BCK on the respective channel (loopback)
848 * #GNUNET_SYSERR if message on a one-ended channel (remote)
851 handle_data (struct MeshTunnel3 *t,
852 const struct GNUNET_MESH_Data *msg,
855 struct MeshChannel *ch;
860 size = ntohs (msg->header.size);
862 sizeof (struct GNUNET_MESH_Data) +
863 sizeof (struct GNUNET_MessageHeader))
868 type = ntohs (msg->header.type);
869 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message\n",
870 GNUNET_MESH_DEBUG_M2S (type));
871 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
872 GNUNET_MESH_DEBUG_M2S (ntohs (msg[1].header.type)));
875 ch = GMT_get_channel (t, ntohl (msg->chid));
878 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
880 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
885 GMT_change_state (t, MESH_TUNNEL3_READY);
886 GMCH_handle_data (ch, msg, fwd);
891 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
893 * @param t Tunnel on which the DATA ACK came.
894 * @param msg DATA ACK message.
895 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
896 * #GNUNET_YES if message is FWD on the respective channel (loopback)
897 * #GNUNET_NO if message is BCK on the respective channel (loopback)
898 * #GNUNET_SYSERR if message on a one-ended channel (remote)
901 handle_data_ack (struct MeshTunnel3 *t,
902 const struct GNUNET_MESH_DataACK *msg,
905 struct MeshChannel *ch;
909 size = ntohs (msg->header.size);
910 if (size != sizeof (struct GNUNET_MESH_DataACK))
917 ch = GMT_get_channel (t, ntohl (msg->chid));
920 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
922 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
927 GMCH_handle_data_ack (ch, msg, fwd);
932 * Handle channel create.
934 * @param t Tunnel on which the data came.
935 * @param msg Data message.
938 handle_ch_create (struct MeshTunnel3 *t,
939 const struct GNUNET_MESH_ChannelCreate *msg)
941 struct MeshChannel *ch;
945 size = ntohs (msg->header.size);
946 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
953 ch = GMT_get_channel (t, ntohl (msg->chid));
954 if (NULL != ch && ! GMT_is_loopback (t))
956 /* Probably a retransmission, safe to ignore */
957 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
961 ch = GMCH_handle_create (t, msg);
964 GMT_add_channel (t, ch);
970 * Handle channel NACK.
972 * @param t Tunnel on which the data came.
973 * @param msg Data message.
976 handle_ch_nack (struct MeshTunnel3 *t,
977 const struct GNUNET_MESH_ChannelManage *msg)
979 struct MeshChannel *ch;
983 size = ntohs (msg->header.size);
984 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
991 ch = GMT_get_channel (t, ntohl (msg->chid));
992 if (NULL != ch && ! GMT_is_loopback (t))
994 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
996 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1001 GMCH_handle_nack (ch);
1006 * Handle a CHANNEL ACK (SYNACK/ACK).
1008 * @param t Tunnel on which the CHANNEL ACK came.
1009 * @param msg CHANNEL ACK message.
1010 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1011 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1012 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1013 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1016 handle_ch_ack (struct MeshTunnel3 *t,
1017 const struct GNUNET_MESH_ChannelManage *msg,
1020 struct MeshChannel *ch;
1024 size = ntohs (msg->header.size);
1025 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1032 ch = GMT_get_channel (t, ntohl (msg->chid));
1035 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1037 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1042 GMCH_handle_ack (ch, msg, fwd);
1048 * Handle a channel destruction message.
1050 * @param t Tunnel on which the message came.
1051 * @param msg Channel destroy message.
1052 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1053 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1054 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1055 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1058 handle_ch_destroy (struct MeshTunnel3 *t,
1059 const struct GNUNET_MESH_ChannelManage *msg,
1062 struct MeshChannel *ch;
1066 size = ntohs (msg->header.size);
1067 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1074 ch = GMT_get_channel (t, ntohl (msg->chid));
1077 /* Probably a retransmission, safe to ignore */
1081 GMCH_handle_destroy (ch, msg, fwd);
1086 * The peer's ephemeral key has changed: update the symmetrical keys.
1088 * @param t Tunnel this message came on.
1089 * @param msg Key eXchange message.
1092 handle_ephemeral (struct MeshTunnel3 *t,
1093 const struct GNUNET_MESH_KX_Ephemeral *msg)
1095 struct GNUNET_HashCode km;
1096 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1098 if (GNUNET_OK != check_ephemeral (t, msg))
1100 GNUNET_break_op (0);
1103 derive_key_material (&km, &msg->ephemeral_key);
1104 LOG (GNUNET_ERROR_TYPE_DEBUG, " km is %s\n", GNUNET_h2s (&km));
1105 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1106 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1107 if (MESH_TUNNEL3_KEY_SENT == t->state)
1109 LOG (GNUNET_ERROR_TYPE_DEBUG, " our key was sent, send ping\n");
1111 t->state = MESH_TUNNEL3_PING_SENT;
1117 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1118 * Answer with by retransmitting the challenge with the "opposite" key.
1120 * @param t Tunnel this message came on.
1121 * @param msg Key eXchange Ping message.
1124 handle_ping (struct MeshTunnel3 *t,
1125 const struct GNUNET_MESH_KX_Ping *msg)
1127 struct GNUNET_MESH_KX_Ping res;
1129 if (ntohs (msg->header.size) != sizeof (res))
1131 GNUNET_break_op (0);
1135 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1136 t_decrypt (t, &res.target, &msg->target, ping_encryption_size (), msg->iv);
1137 if (0 != memcmp (&my_full_id, &res.target, sizeof (my_full_id)))
1140 LOG (GNUNET_ERROR_TYPE_DEBUG, " e got %u\n", msg->nonce);
1141 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg->target));
1142 LOG (GNUNET_ERROR_TYPE_DEBUG, " got %u\n", res.nonce);
1143 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&res.target));
1147 send_pong (t, res.nonce);
1152 * Peer has answer to our challenge.
1153 * If answer is successful, consider the key exchange finished and clean
1154 * up all related state.
1156 * @param t Tunnel this message came on.
1157 * @param msg Key eXchange Pong message.
1160 handle_pong (struct MeshTunnel3 *t,
1161 const struct GNUNET_MESH_KX_Pong *msg)
1165 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1166 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1168 GNUNET_break_op (0);
1171 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1173 if (challenge != t->kx_ctx->challenge)
1175 LOG (GNUNET_ERROR_TYPE_DEBUG,
1176 "Wrong PONG challenge: %u (e: %u). Expected: %u.\n",
1177 challenge, msg->nonce, t->kx_ctx->challenge);
1178 GNUNET_break_op (0);
1181 GNUNET_SCHEDULER_cancel (t->rekey_task);
1182 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1183 GNUNET_free (t->kx_ctx);
1185 t->state = MESH_TUNNEL3_READY;
1186 send_queued_data (t);
1191 * Demultiplex by message type and call appropriate handler for a message
1192 * towards a channel of a local tunnel.
1194 * @param t Tunnel this message came on.
1195 * @param msgh Message header.
1196 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1197 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1198 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1199 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1202 handle_decrypted (struct MeshTunnel3 *t,
1203 const struct GNUNET_MessageHeader *msgh,
1208 type = ntohs (msgh->type);
1209 LOG (GNUNET_ERROR_TYPE_DEBUG,
1210 "Got a %s message!\n",
1211 GNUNET_MESH_DEBUG_M2S (type));
1215 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1216 /* Don't send hop ACK, wait for client to ACK */
1217 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1220 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1221 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1224 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1225 handle_ch_create (t,
1226 (struct GNUNET_MESH_ChannelCreate *) msgh);
1229 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1231 (struct GNUNET_MESH_ChannelManage *) msgh);
1234 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1236 (struct GNUNET_MESH_ChannelManage *) msgh,
1240 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1241 handle_ch_destroy (t,
1242 (struct GNUNET_MESH_ChannelManage *) msgh,
1247 GNUNET_break_op (0);
1248 LOG (GNUNET_ERROR_TYPE_DEBUG,
1249 "end-to-end message not known (%u)\n",
1250 ntohs (msgh->type));
1254 /******************************************************************************/
1255 /******************************** API ***********************************/
1256 /******************************************************************************/
1259 * Decrypt and demultiplex by message type. Call appropriate handler
1260 * for every message.
1262 * @param t Tunnel this message came on.
1263 * @param msg Encrypted message.
1266 GMT_handle_encrypted (struct MeshTunnel3 *t,
1267 const struct GNUNET_MESH_Encrypted *msg)
1269 size_t size = ntohs (msg->header.size);
1270 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1271 size_t decrypted_size;
1272 char cbuf [payload_size];
1273 struct GNUNET_MessageHeader *msgh;
1276 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1278 while (off < decrypted_size)
1280 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1281 handle_decrypted (t, msgh, GNUNET_SYSERR);
1282 off += ntohs (msgh->size);
1288 * Demultiplex an encapsulated KX message by message type.
1290 * @param t Tunnel on which the message came.
1291 * @param message Payload of KX message.
1294 GMT_handle_kx (struct MeshTunnel3 *t,
1295 const struct GNUNET_MessageHeader *message)
1299 type = ntohs (message->type);
1300 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1303 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1304 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1307 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1308 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1311 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1312 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1316 GNUNET_break_op (0);
1317 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1323 * Initialize the tunnel subsystem.
1325 * @param c Configuration handle.
1326 * @param key ECC private key, to derive all other keys and do crypto.
1329 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1330 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1332 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1334 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1337 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1338 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1342 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1345 rekey_period = GNUNET_TIME_UNIT_DAYS;
1348 my_private_key = key;
1349 kx_msg.header.size = htons (sizeof (kx_msg));
1350 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1351 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1352 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1353 kx_msg.origin_identity = my_full_id;
1354 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1356 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1361 * Shut down the tunnel subsystem.
1366 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1368 GNUNET_SCHEDULER_cancel (rekey_task);
1369 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1371 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1378 * @param destination Peer this tunnel is towards.
1380 struct MeshTunnel3 *
1381 GMT_new (struct MeshPeer *destination)
1383 struct MeshTunnel3 *t;
1385 t = GNUNET_new (struct MeshTunnel3);
1387 t->peer = destination;
1390 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1391 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1402 * Change the tunnel state.
1404 * @param t Tunnel whose state to change.
1405 * @param state New state.
1408 GMT_change_state (struct MeshTunnel3* t, enum MeshTunnel3State state)
1412 LOG (GNUNET_ERROR_TYPE_DEBUG,
1413 "Tunnel %s state was %s\n",
1415 GMT_state2s (t->state));
1416 LOG (GNUNET_ERROR_TYPE_DEBUG,
1417 "Tunnel %s state is now %s\n",
1419 GMT_state2s (state));
1420 if (myid != GMP_get_short_id (t->peer) &&
1421 MESH_TUNNEL3_WAITING == t->state && MESH_TUNNEL3_READY == state)
1423 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1424 rekey_tunnel (t, NULL);
1425 LOG (GNUNET_ERROR_TYPE_DEBUG,
1426 "Tunnel %s state is now %s\n",
1428 GMT_state2s (t->state));
1434 if (MESH_TUNNEL3_READY == state && 3 <= GMT_count_connections (t))
1436 GMP_stop_search (t->peer);
1442 * Add a connection to a tunnel.
1445 * @param c Connection.
1448 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1450 struct MeshTConnection *aux;
1452 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1456 aux = GNUNET_new (struct MeshTConnection);
1458 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1463 * Remove a connection from a tunnel.
1466 * @param c Connection.
1469 GMT_remove_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1471 struct MeshTConnection *aux;
1473 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1476 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1484 * Add a channel to a tunnel.
1487 * @param ch Channel.
1490 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1492 struct MeshTChannel *aux;
1494 GNUNET_assert (NULL != ch);
1496 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1498 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1500 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1505 aux = GNUNET_new (struct MeshTChannel);
1507 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1508 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1513 * Remove a channel from a tunnel.
1516 * @param ch Channel.
1519 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1521 struct MeshTChannel *aux;
1523 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1524 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1528 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1529 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1538 * Search for a channel by global ID.
1540 * @param t Tunnel containing the channel.
1541 * @param chid Public channel number.
1543 * @return channel handler, NULL if doesn't exist
1545 struct MeshChannel *
1546 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1548 struct MeshTChannel *iter;
1553 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1555 if (GMCH_get_id (iter->ch) == chid)
1559 return NULL == iter ? NULL : iter->ch;
1564 * Tunnel is empty: destroy it.
1566 * Notifies all connections about the destruction.
1568 * @param t Tunnel to destroy.
1571 GMT_destroy_empty (struct MeshTunnel3 *t)
1573 struct MeshTConnection *iter;
1575 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1577 GMC_send_destroy (iter->c);
1580 t->destroy = GNUNET_YES;
1585 * Destroy tunnel if empty (no more channels).
1587 * @param t Tunnel to destroy if empty.
1590 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1592 if (1 < GMT_count_channels (t))
1595 GMT_destroy_empty (t);
1600 * Destroy the tunnel.
1602 * This function does not generate any warning traffic to clients or peers.
1605 * Cancel messages belonging to this tunnel queued to neighbors.
1606 * Free any allocated resources linked to the tunnel.
1608 * @param t The tunnel to destroy.
1611 GMT_destroy (struct MeshTunnel3 *t)
1613 struct MeshTConnection *iter;
1614 struct MeshTConnection *next;
1619 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
1621 // if (GNUNET_YES != GNUNET_CONTAINER_multihashmap_remove (tunnels, &t->id, t))
1622 // GNUNET_break (0);
1624 for (iter = t->connection_head; NULL != iter; iter = next)
1627 GMC_destroy (iter->c);
1630 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
1631 GMP_set_tunnel (t->peer, NULL);
1633 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1634 GNUNET_SCHEDULER_cancel (t->rekey_task);
1641 * @brief Use the given path for the tunnel.
1642 * Update the next and prev hops (and RCs).
1643 * (Re)start the path refresh in case the tunnel is locally owned.
1645 * @param t Tunnel to update.
1646 * @param p Path to use.
1648 * @return Connection created.
1650 struct MeshConnection *
1651 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
1653 struct MeshConnection *c;
1654 struct GNUNET_HashCode cid;
1655 unsigned int own_pos;
1657 if (NULL == t || NULL == p)
1663 for (own_pos = 0; own_pos < p->length; own_pos++)
1665 if (p->peers[own_pos] == myid)
1668 if (own_pos > p->length - 1)
1674 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
1675 c = GMC_new (&cid, t, p, own_pos);
1676 GMT_add_connection (t, c);
1682 * Count established (ready) connections of a tunnel.
1684 * @param t Tunnel on which to count.
1686 * @return Number of connections.
1689 GMT_count_connections (struct MeshTunnel3 *t)
1691 struct MeshTConnection *iter;
1694 for (count = 0, iter = t->connection_head;
1696 iter = iter->next, count++);
1702 * Count channels of a tunnel.
1704 * @param t Tunnel on which to count.
1706 * @return Number of channels.
1709 GMT_count_channels (struct MeshTunnel3 *t)
1711 struct MeshTChannel *iter;
1714 for (count = 0, iter = t->channel_head;
1716 iter = iter->next, count++) /* skip */;
1723 * Get the state of a tunnel.
1727 * @return Tunnel's state.
1729 enum MeshTunnel3State
1730 GMT_get_state (struct MeshTunnel3 *t)
1735 return (enum MeshTunnel3State) -1;
1742 * Get the maximum buffer space for a tunnel towards a local client.
1746 * @return Biggest buffer space offered by any channel in the tunnel.
1749 GMT_get_channels_buffer (struct MeshTunnel3 *t)
1751 struct MeshTChannel *iter;
1752 unsigned int buffer;
1753 unsigned int ch_buf;
1755 if (NULL == t->channel_head)
1757 /* Probably getting buffer for a channel create/handshake. */
1762 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1764 ch_buf = get_channel_buffer (iter);
1765 if (ch_buf > buffer)
1773 * Get the total buffer space for a tunnel for P2P traffic.
1777 * @return Buffer space offered by all connections in the tunnel.
1780 GMT_get_connections_buffer (struct MeshTunnel3 *t)
1782 struct MeshTConnection *iter;
1783 unsigned int buffer;
1785 iter = t->connection_head;
1787 while (NULL != iter)
1789 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
1795 buffer += get_connection_buffer (iter);
1804 * Get the tunnel's destination.
1808 * @return ID of the destination peer.
1810 const struct GNUNET_PeerIdentity *
1811 GMT_get_destination (struct MeshTunnel3 *t)
1813 return GMP_get_id (t->peer);
1818 * Get the tunnel's next free global channel ID.
1822 * @return GID of a channel free to use.
1825 GMT_get_next_chid (struct MeshTunnel3 *t)
1827 MESH_ChannelNumber chid;
1829 while (NULL != GMT_get_channel (t, t->next_chid))
1831 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
1832 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
1834 chid = t->next_chid;
1835 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
1842 * Send ACK on one or more channels due to buffer in connections.
1844 * @param t Channel which has some free buffer space.
1847 GMT_unchoke_channels (struct MeshTunnel3 *t)
1849 struct MeshTChannel *iter;
1850 unsigned int buffer;
1851 unsigned int channels = GMT_count_channels (t);
1852 unsigned int choked_n;
1853 struct MeshChannel *choked[channels];
1855 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
1856 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
1857 if (NULL != t->channel_head)
1858 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
1866 /* Get buffer space */
1867 buffer = GMT_get_connections_buffer (t);
1873 /* Count and remember choked channels */
1875 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1877 if (GNUNET_NO == get_channel_allowed (iter))
1879 choked[choked_n++] = iter->ch;
1883 /* Unchoke random channels */
1884 while (0 < buffer && 0 < choked_n)
1886 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1888 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
1891 choked[r] = choked[choked_n];
1897 * Send ACK on one or more connections due to buffer space to the client.
1899 * Iterates all connections of the tunnel and sends ACKs appropriately.
1904 GMT_send_connection_acks (struct MeshTunnel3 *t)
1906 struct MeshTConnection *iter;
1909 uint32_t allow_per_connection;
1911 unsigned int buffer;
1913 LOG (GNUNET_ERROR_TYPE_DEBUG,
1914 "Tunnel send connection ACKs on %s\n",
1923 buffer = GMT_get_channels_buffer (t);
1925 /* Count connections, how many messages are already allowed */
1926 cs = GMT_count_connections (t);
1927 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
1929 allowed += get_connection_allowed (iter);
1932 /* Make sure there is no overflow */
1933 if (allowed > buffer)
1938 /* Authorize connections to send more data */
1939 to_allow = buffer; /* - allowed; */
1941 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
1943 allow_per_connection = to_allow/cs;
1944 to_allow -= allow_per_connection;
1946 if (get_connection_allowed (iter) > 64 / 3)
1950 GMC_allow (iter->c, buffer, GMC_is_origin (iter->c, GNUNET_YES));
1953 GNUNET_break (to_allow == 0);
1958 * Sends an already built message on a tunnel, encrypting it and
1959 * choosing the best connection.
1961 * @param message Message to send. Function modifies it.
1962 * @param t Tunnel on which this message is transmitted.
1963 * @param ch Channel on which this message is transmitted.
1964 * @param fwd Is this a fwd message on @c ch?
1967 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
1968 struct MeshTunnel3 *t,
1969 struct MeshChannel *ch,
1972 struct MeshConnection *c;
1973 struct GNUNET_MESH_Encrypted *msg;
1974 size_t size = ntohs (message->size);
1975 size_t encrypted_size;
1976 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
1980 if (MESH_TUNNEL3_READY != t->state)
1982 queue_data (t, ch, message);
1985 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
1987 if (GMT_is_loopback (t))
1989 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
1990 handle_decrypted (t, message, fwd);
1994 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
1995 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
1996 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
1998 encrypted_size = t_encrypt (t, &msg[1], message, size, iv);
1999 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + encrypted_size);
2000 c = tunnel_get_connection (t);
2003 GNUNET_break (GNUNET_YES == t->destroy);
2006 type = ntohs (message->type);
2009 case GNUNET_MESSAGE_TYPE_MESH_DATA:
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 GMC_send_prebuilt_message (&msg->header, c, fwd);
2027 * Is the tunnel directed towards the local peer?
2031 * @return #GNUNET_YES if it is loopback.
2034 GMT_is_loopback (const struct MeshTunnel3 *t)
2036 return (myid == GMP_get_short_id (t->peer));
2041 * Is the tunnel this path already?
2046 * @return #GNUNET_YES a connection uses this path.
2049 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2051 struct MeshTConnection *iter;
2053 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2054 if (GMC_get_path (iter->c) == p)
2062 * Get a cost of a path for a tunnel considering existing connections.
2065 * @param path Candidate path.
2067 * @return Cost of the path (path length + number of overlapping nodes)
2070 GMT_get_path_cost (const struct MeshTunnel3 *t,
2071 const struct MeshPeerPath *path)
2073 struct MeshTConnection *iter;
2074 unsigned int overlap;
2082 GNUNET_assert (NULL != t);
2084 for (i = 0; i < path->length; i++)
2086 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2088 for (j = 0; j < GMC_get_path (iter->c)->length; j++)
2090 if (path->peers[i] == GMC_get_path (iter->c)->peers[j])
2098 return (path->length + overlap) * (path->score * -1);
2103 * Get the static string for the peer this tunnel is directed.
2107 * @return Static string the destination peer's ID.
2110 GMT_2s (const struct MeshTunnel3 *t)
2115 return GMP_2s (t->peer);