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;
166 * Tunnel queue given to the channel to cancel request. Update on send_queued.
168 struct MeshTunnel3Queue *tq;
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 *cq;
188 * Handle in case message hasn't been given to a connection yet.
190 struct MeshTunnelDelayed *tqd;
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));
611 * Callback called when a queued message is sent.
613 * Calculates the average time and connection packet tracking.
615 * @param cls Closure (TunnelQueue handle).
616 * @param c Connection this message was on.
617 * @param q Connection queue handle (unused).
618 * @param type Type of message sent.
619 * @param fwd Was this a FWD going message?
620 * @param size Size of the message.
623 message_sent (void *cls,
624 struct MeshConnection *c,
625 struct MeshConnectionQueue *q,
626 uint16_t type, int fwd, size_t size)
628 struct MeshTunnel3Queue *qt = cls;
630 GNUNET_assert (NULL != qt->cont);
631 qt->cont (qt->cont_cls, GMC_get_tunnel (c), qt, type, size);
637 * Delete a queued message: either was sent or the channel was destroyed
638 * before the tunnel's key exchange had a chance to finish.
640 * @param tq Queue handle.
643 unqueue_data (struct MeshTunnelDelayed *tq)
645 GNUNET_CONTAINER_DLL_remove (tq->t->tq_head, tq->t->tq_tail, tq);
651 * Cache a message to be sent once tunnel is online.
653 * @param t Tunnel to hold the message.
654 * @param msg Message itself (copy will be made).
656 static struct MeshTunnelDelayed *
657 queue_data (struct MeshTunnel3 *t, const struct GNUNET_MessageHeader *msg)
659 struct MeshTunnelDelayed *tqd;
660 uint16_t size = ntohs (msg->size);
662 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue data on Tunnel %s\n", GMT_2s (t));
664 if (GNUNET_YES == is_ready (t))
670 tqd = GNUNET_malloc (sizeof (struct MeshTunnelDelayed) + size);
673 memcpy (&tqd[1], msg, size);
674 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tqd);
681 * Sends an already built message on a tunnel, encrypting it and
682 * choosing the best connection.
684 * @param message Message to send. Function modifies it.
685 * @param t Tunnel on which this message is transmitted.
686 * @param force Force the tunnel to take the message (buffer overfill).
687 * @param cont Continuation to call once message is really sent.
688 * @param cont_cls Closure for @c cont.
689 * @param existing_q In case this a transmission of previously queued data,
690 * this should be TunnelQueue given to the client.
693 * @return Handle to cancel message. NULL if @c cont is NULL.
695 static struct MeshTunnel3Queue *
696 send_prebuilt_message (const struct GNUNET_MessageHeader *message,
697 struct MeshTunnel3 *t, int force,
698 GMT_sent cont, void *cont_cls,
699 struct MeshTunnel3Queue *existing_q)
701 struct MeshTunnel3Queue *tq;
702 struct MeshConnection *c;
703 struct GNUNET_MESH_Encrypted *msg;
704 size_t size = ntohs (message->size);
705 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
710 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
712 if (GNUNET_NO == is_ready (t))
714 struct MeshTunnelDelayed *tqd;
715 /* A non null existing_q indicates sending of queued data.
716 * Should only happen after tunnel becomes ready.
718 GNUNET_assert (NULL == existing_q);
719 tqd = queue_data (t, message);
722 tq = GNUNET_new (struct MeshTunnel3Queue);
726 tq->cont_cls = cont_cls;
730 GNUNET_assert (GNUNET_NO == GMT_is_loopback (t));
732 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
733 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
734 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
736 GNUNET_assert (t_encrypt (t, &msg[1], message, size, iv) == size);
737 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + size);
738 c = tunnel_get_connection (t);
741 GNUNET_break (GNUNET_YES == t->destroy);
744 type = ntohs (message->type);
747 case GNUNET_MESSAGE_TYPE_MESH_DATA:
748 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
749 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
750 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
751 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
752 msg->cid = *GMC_get_id (c);
753 msg->ttl = htonl (default_ttl);
756 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
761 fwd = GMC_is_origin (c, GNUNET_YES);
765 (void) GMC_send_prebuilt_message (&msg->header, c, fwd, force, NULL, NULL);
768 if (NULL == existing_q)
770 tq = GNUNET_new (struct MeshTunnel3Queue); /* FIXME valgrind: leak*/
777 tq->cq = GMC_send_prebuilt_message (&msg->header, c, fwd, force,
780 tq->cont_cls = cont_cls;
787 * Send all cached messages that we can, tunnel is online.
789 * @param t Tunnel that holds the messages. Cannot be loopback.
792 send_queued_data (struct MeshTunnel3 *t)
794 struct MeshTunnelDelayed *tqd;
795 struct MeshTunnelDelayed *next;
798 LOG (GNUNET_ERROR_TYPE_DEBUG,
799 "GMT_send_queued_data on tunnel %s\n",
802 if (GMT_is_loopback (t))
808 if (GNUNET_NO == is_ready (t))
810 LOG (GNUNET_ERROR_TYPE_DEBUG, " not ready yet: %s/%s\n",
811 estate2s (t->estate), cstate2s (t->cstate));
815 room = GMT_get_connections_buffer (t);
816 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
817 LOG (GNUNET_ERROR_TYPE_DEBUG, " tq head: %p\n", t->tq_head);
818 for (tqd = t->tq_head; NULL != tqd && room > 0; tqd = next)
820 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending queued data\n");
823 send_prebuilt_message ((struct GNUNET_MessageHeader *) &tqd[1],
825 NULL != tqd->tq ? tqd->tq->cont : NULL,
826 NULL != tqd->tq ? tqd->tq->cont_cls : NULL,
830 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_send_queued_data end\n", GMP_2s (t->peer));
835 * Sends key exchange message on a tunnel, choosing the best connection.
836 * Should not be called on loopback tunnels.
838 * @param t Tunnel on which this message is transmitted.
839 * @param message Message to send. Function modifies it.
842 send_kx (struct MeshTunnel3 *t,
843 const struct GNUNET_MessageHeader *message)
845 struct MeshConnection *c;
846 struct GNUNET_MESH_KX *msg;
847 size_t size = ntohs (message->size);
848 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
852 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
854 /* Avoid loopback. */
855 if (GMT_is_loopback (t))
857 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
862 /* Must have a connection. */
863 if (NULL == t->connection_head)
869 msg = (struct GNUNET_MESH_KX *) cbuf;
870 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
871 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
872 c = tunnel_get_connection (t);
875 GNUNET_break (GNUNET_YES == t->destroy);
878 type = ntohs (message->type);
881 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
882 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
883 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
884 msg->reserved = htonl (0);
885 memcpy (&msg[1], message, size);
888 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
893 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
894 /* TODO save handle and cancel in case of a unneeded retransmission */
895 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
900 * Send the ephemeral key on a tunnel.
902 * @param t Tunnel on which to send the key.
905 send_ephemeral (struct MeshTunnel3 *t)
907 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
909 kx_msg.sender_status = htonl (t->estate);
910 send_kx (t, &kx_msg.header);
914 * Send a ping message on a tunnel.
916 * @param t Tunnel on which to send the ping.
919 send_ping (struct MeshTunnel3 *t)
921 struct GNUNET_MESH_KX_Ping msg;
923 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
924 msg.header.size = htons (sizeof (msg));
925 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
926 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
927 msg.target = *GMP_get_id (t->peer);
928 msg.nonce = t->kx_ctx->challenge;
930 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
931 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&msg.target));
932 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
933 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
934 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg.target));
936 send_kx (t, &msg.header);
941 * Send a pong message on a tunnel.
943 * @param t Tunnel on which to send the pong.
944 * @param challenge Value sent in the ping that we have to send back.
947 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
949 struct GNUNET_MESH_KX_Pong msg;
951 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
952 msg.header.size = htons (sizeof (msg));
953 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
954 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
955 msg.nonce = challenge;
956 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
957 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
958 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
960 send_kx (t, &msg.header);
965 * Initiate a rekey with the remote peer.
967 * @param cls Closure (tunnel).
968 * @param tc TaskContext.
971 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
973 struct MeshTunnel3 *t = cls;
975 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
977 LOG (GNUNET_ERROR_TYPE_DEBUG, "Re-key Tunnel\n");
978 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
981 if (NULL == t->kx_ctx)
983 LOG (GNUNET_ERROR_TYPE_DEBUG, " new kx ctx\n");
984 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
985 t->kx_ctx->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
987 t->kx_ctx->d_key_old = t->d_key;
992 case MESH_TUNNEL3_KEY_UNINITIALIZED:
993 t->estate = MESH_TUNNEL3_KEY_SENT;
995 case MESH_TUNNEL3_KEY_SENT:
997 case MESH_TUNNEL3_KEY_PING:
998 case MESH_TUNNEL3_KEY_OK:
1000 t->estate = MESH_TUNNEL3_KEY_PING;
1003 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->estate);
1006 LOG (GNUNET_ERROR_TYPE_DEBUG, " next call in %s\n",
1007 GNUNET_STRINGS_relative_time_to_string (REKEY_WAIT, GNUNET_YES));
1008 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
1013 * Out ephemeral key has changed, create new session key on all tunnels.
1015 * @param cls Closure (size of the hashmap).
1016 * @param key Current public key.
1017 * @param value Value in the hash map (tunnel).
1019 * @return #GNUNET_YES, so we should continue to iterate,
1022 rekey_iterator (void *cls,
1023 const struct GNUNET_PeerIdentity *key,
1026 struct MeshTunnel3 *t = value;
1027 struct GNUNET_TIME_Relative delay;
1028 long n = (long) cls;
1031 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1034 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
1035 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
1036 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
1043 * Create a new ephemeral key and key message, schedule next rekeying.
1045 * @param cls Closure (unused).
1046 * @param tc TaskContext.
1049 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1051 struct GNUNET_TIME_Absolute time;
1054 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1056 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
1059 GNUNET_free_non_null (my_ephemeral_key);
1060 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
1062 time = GNUNET_TIME_absolute_get ();
1063 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
1064 time = GNUNET_TIME_absolute_add (time, rekey_period);
1065 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
1066 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
1067 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
1069 GNUNET_assert (GNUNET_OK ==
1070 GNUNET_CRYPTO_eddsa_sign (my_private_key,
1072 &kx_msg.signature));
1074 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
1075 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
1077 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
1082 * Called only on shutdown, destroy every tunnel.
1084 * @param cls Closure (unused).
1085 * @param key Current public key.
1086 * @param value Value in the hash map (tunnel).
1088 * @return #GNUNET_YES, so we should continue to iterate,
1091 destroy_iterator (void *cls,
1092 const struct GNUNET_PeerIdentity *key,
1095 struct MeshTunnel3 *t = value;
1103 * Demultiplex data per channel and call appropriate channel handler.
1105 * @param t Tunnel on which the data came.
1106 * @param msg Data message.
1107 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1108 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1109 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1110 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1113 handle_data (struct MeshTunnel3 *t,
1114 const struct GNUNET_MESH_Data *msg,
1117 struct MeshChannel *ch;
1121 size = ntohs (msg->header.size);
1123 sizeof (struct GNUNET_MESH_Data) +
1124 sizeof (struct GNUNET_MessageHeader))
1129 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
1130 GM_m2s (ntohs (msg[1].header.type)));
1133 ch = GMT_get_channel (t, ntohl (msg->chid));
1136 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
1138 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1143 GMCH_handle_data (ch, msg, fwd);
1148 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
1150 * @param t Tunnel on which the DATA ACK came.
1151 * @param msg DATA ACK message.
1152 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1153 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1154 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1155 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1158 handle_data_ack (struct MeshTunnel3 *t,
1159 const struct GNUNET_MESH_DataACK *msg,
1162 struct MeshChannel *ch;
1166 size = ntohs (msg->header.size);
1167 if (size != sizeof (struct GNUNET_MESH_DataACK))
1174 ch = GMT_get_channel (t, ntohl (msg->chid));
1177 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
1179 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1184 GMCH_handle_data_ack (ch, msg, fwd);
1189 * Handle channel create.
1191 * @param t Tunnel on which the data came.
1192 * @param msg Data message.
1195 handle_ch_create (struct MeshTunnel3 *t,
1196 const struct GNUNET_MESH_ChannelCreate *msg)
1198 struct MeshChannel *ch;
1202 size = ntohs (msg->header.size);
1203 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
1210 ch = GMT_get_channel (t, ntohl (msg->chid));
1211 if (NULL != ch && ! GMT_is_loopback (t))
1213 /* Probably a retransmission, safe to ignore */
1214 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
1218 ch = GMCH_handle_create (t, msg);
1221 GMT_add_channel (t, ch);
1227 * Handle channel NACK: check correctness and call channel handler for NACKs.
1229 * @param t Tunnel on which the NACK came.
1230 * @param msg NACK message.
1233 handle_ch_nack (struct MeshTunnel3 *t,
1234 const struct GNUNET_MESH_ChannelManage *msg)
1236 struct MeshChannel *ch;
1240 size = ntohs (msg->header.size);
1241 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1248 ch = GMT_get_channel (t, ntohl (msg->chid));
1251 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
1253 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1258 GMCH_handle_nack (ch);
1263 * Handle a CHANNEL ACK (SYNACK/ACK).
1265 * @param t Tunnel on which the CHANNEL ACK came.
1266 * @param msg CHANNEL ACK message.
1267 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1268 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1269 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1270 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1273 handle_ch_ack (struct MeshTunnel3 *t,
1274 const struct GNUNET_MESH_ChannelManage *msg,
1277 struct MeshChannel *ch;
1281 size = ntohs (msg->header.size);
1282 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1289 ch = GMT_get_channel (t, ntohl (msg->chid));
1292 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1294 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1299 GMCH_handle_ack (ch, msg, fwd);
1305 * Handle a channel destruction message.
1307 * @param t Tunnel on which the message came.
1308 * @param msg Channel destroy message.
1309 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1310 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1311 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1312 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1315 handle_ch_destroy (struct MeshTunnel3 *t,
1316 const struct GNUNET_MESH_ChannelManage *msg,
1319 struct MeshChannel *ch;
1323 size = ntohs (msg->header.size);
1324 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1331 ch = GMT_get_channel (t, ntohl (msg->chid));
1334 /* Probably a retransmission, safe to ignore */
1338 GMCH_handle_destroy (ch, msg, fwd);
1343 * The peer's ephemeral key has changed: update the symmetrical keys.
1345 * @param t Tunnel this message came on.
1346 * @param msg Key eXchange message.
1349 handle_ephemeral (struct MeshTunnel3 *t,
1350 const struct GNUNET_MESH_KX_Ephemeral *msg)
1352 struct GNUNET_HashCode km;
1353 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1355 if (GNUNET_OK != check_ephemeral (t, msg))
1357 GNUNET_break_op (0);
1360 derive_key_material (&km, &msg->ephemeral_key);
1361 LOG (GNUNET_ERROR_TYPE_DEBUG, " km is %s\n", GNUNET_h2s (&km));
1362 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1363 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1364 if (MESH_TUNNEL3_KEY_SENT == t->estate)
1366 LOG (GNUNET_ERROR_TYPE_DEBUG, " our key was sent, send ping\n");
1368 t->estate = MESH_TUNNEL3_KEY_PING;
1374 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1375 * Answer with by retransmitting the challenge with the "opposite" key.
1377 * @param t Tunnel this message came on.
1378 * @param msg Key eXchange Ping message.
1381 handle_ping (struct MeshTunnel3 *t,
1382 const struct GNUNET_MESH_KX_Ping *msg)
1384 struct GNUNET_MESH_KX_Ping res;
1386 if (ntohs (msg->header.size) != sizeof (res))
1388 GNUNET_break_op (0);
1392 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1393 t_decrypt (t, &res.target, &msg->target, ping_encryption_size (), msg->iv);
1394 if (0 != memcmp (&my_full_id, &res.target, sizeof (my_full_id)))
1396 GNUNET_break_op (0);
1397 LOG (GNUNET_ERROR_TYPE_DEBUG, " e got %u\n", msg->nonce);
1398 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg->target));
1399 LOG (GNUNET_ERROR_TYPE_DEBUG, " got %u\n", res.nonce);
1400 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&res.target));
1404 send_pong (t, res.nonce);
1409 * Peer has answer to our challenge.
1410 * If answer is successful, consider the key exchange finished and clean
1411 * up all related state.
1413 * @param t Tunnel this message came on.
1414 * @param msg Key eXchange Pong message.
1417 handle_pong (struct MeshTunnel3 *t,
1418 const struct GNUNET_MESH_KX_Pong *msg)
1422 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1423 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1425 GNUNET_break_op (0);
1428 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1430 if (challenge != t->kx_ctx->challenge)
1432 LOG (GNUNET_ERROR_TYPE_DEBUG,
1433 "Wrong PONG challenge: %u (e: %u). Expected: %u.\n",
1434 challenge, msg->nonce, t->kx_ctx->challenge);
1435 GNUNET_break_op (0);
1438 GNUNET_SCHEDULER_cancel (t->rekey_task);
1439 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1440 GNUNET_free (t->kx_ctx);
1442 GMT_change_estate (t, MESH_TUNNEL3_KEY_OK);
1447 * Demultiplex by message type and call appropriate handler for a message
1448 * towards a channel of a local tunnel.
1450 * @param t Tunnel this message came on.
1451 * @param msgh Message header.
1452 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1453 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1454 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1455 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1458 handle_decrypted (struct MeshTunnel3 *t,
1459 const struct GNUNET_MessageHeader *msgh,
1464 type = ntohs (msgh->type);
1465 LOG (GNUNET_ERROR_TYPE_DEBUG,
1466 "Got a %s message!\n",
1471 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1472 /* Don't send hop ACK, wait for client to ACK */
1473 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1476 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1477 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1480 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1481 handle_ch_create (t,
1482 (struct GNUNET_MESH_ChannelCreate *) msgh);
1485 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1487 (struct GNUNET_MESH_ChannelManage *) msgh);
1490 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1492 (struct GNUNET_MESH_ChannelManage *) msgh,
1496 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1497 handle_ch_destroy (t,
1498 (struct GNUNET_MESH_ChannelManage *) msgh,
1503 GNUNET_break_op (0);
1504 LOG (GNUNET_ERROR_TYPE_DEBUG,
1505 "end-to-end message not known (%u)\n",
1506 ntohs (msgh->type));
1510 /******************************************************************************/
1511 /******************************** API ***********************************/
1512 /******************************************************************************/
1515 * Decrypt and demultiplex by message type. Call appropriate handler
1516 * for every message.
1518 * @param t Tunnel this message came on.
1519 * @param msg Encrypted message.
1522 GMT_handle_encrypted (struct MeshTunnel3 *t,
1523 const struct GNUNET_MESH_Encrypted *msg)
1525 size_t size = ntohs (msg->header.size);
1526 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1527 size_t decrypted_size;
1528 char cbuf [payload_size];
1529 struct GNUNET_MessageHeader *msgh;
1532 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1534 while (off < decrypted_size)
1536 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1537 handle_decrypted (t, msgh, GNUNET_SYSERR);
1538 off += ntohs (msgh->size);
1544 * Demultiplex an encapsulated KX message by message type.
1546 * @param t Tunnel on which the message came.
1547 * @param message Payload of KX message.
1550 GMT_handle_kx (struct MeshTunnel3 *t,
1551 const struct GNUNET_MessageHeader *message)
1555 type = ntohs (message->type);
1556 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1559 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1560 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1563 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1564 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1567 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1568 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1572 GNUNET_break_op (0);
1573 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1579 * Initialize the tunnel subsystem.
1581 * @param c Configuration handle.
1582 * @param key ECC private key, to derive all other keys and do crypto.
1585 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1586 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1588 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1590 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1593 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1594 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1598 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1601 rekey_period = GNUNET_TIME_UNIT_DAYS;
1604 my_private_key = key;
1605 kx_msg.header.size = htons (sizeof (kx_msg));
1606 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1607 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1608 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1609 kx_msg.origin_identity = my_full_id;
1610 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1612 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1617 * Shut down the tunnel subsystem.
1622 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1624 GNUNET_SCHEDULER_cancel (rekey_task);
1625 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1627 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &destroy_iterator, NULL);
1628 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1635 * @param destination Peer this tunnel is towards.
1637 struct MeshTunnel3 *
1638 GMT_new (struct MeshPeer *destination)
1640 struct MeshTunnel3 *t;
1642 t = GNUNET_new (struct MeshTunnel3);
1644 t->peer = destination;
1647 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1648 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1659 * Change the tunnel's connection state.
1661 * @param t Tunnel whose connection state to change.
1662 * @param cstate New connection state.
1665 GMT_change_cstate (struct MeshTunnel3* t, enum MeshTunnel3CState cstate)
1669 LOG (GNUNET_ERROR_TYPE_DEBUG,
1670 "Tunnel %s cstate was %s\n",
1671 GMP_2s (t->peer), cstate2s (t->cstate));
1672 LOG (GNUNET_ERROR_TYPE_DEBUG,
1673 "Tunnel %s cstate is now %s\n",
1674 GMP_2s (t->peer), cstate2s (cstate));
1675 if (myid != GMP_get_short_id (t->peer) &&
1676 MESH_TUNNEL3_READY != t->cstate &&
1677 MESH_TUNNEL3_READY == cstate)
1680 if (MESH_TUNNEL3_KEY_OK == t->estate)
1682 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered send queued data\n");
1683 send_queued_data (t);
1685 else if (MESH_TUNNEL3_KEY_UNINITIALIZED == t->estate)
1687 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1688 rekey_tunnel (t, NULL);
1693 if (MESH_TUNNEL3_READY == cstate && 3 <= GMT_count_connections (t))
1695 GMP_stop_search (t->peer);
1700 * Change the tunnel encryption state.
1702 * @param t Tunnel whose encryption state to change.
1703 * @param state New encryption state.
1706 GMT_change_estate (struct MeshTunnel3* t, enum MeshTunnel3EState state)
1710 LOG (GNUNET_ERROR_TYPE_DEBUG,
1711 "Tunnel %s estate was %s\n",
1712 GMP_2s (t->peer), estate2s (t->estate));
1713 LOG (GNUNET_ERROR_TYPE_DEBUG,
1714 "Tunnel %s estate is now %s\n",
1715 GMP_2s (t->peer), estate2s (state));
1716 if (myid != GMP_get_short_id (t->peer) &&
1717 MESH_TUNNEL3_KEY_OK != t->estate && MESH_TUNNEL3_KEY_OK == state)
1720 send_queued_data (t);
1728 * Add a connection to a tunnel.
1731 * @param c Connection.
1734 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1736 struct MeshTConnection *aux;
1738 GNUNET_assert (NULL != c);
1740 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1744 aux = GNUNET_new (struct MeshTConnection);
1746 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1751 * Remove a connection from a tunnel.
1754 * @param c Connection.
1757 GMT_remove_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1759 struct MeshTConnection *aux;
1761 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing connection %s from tunnel %s\n",
1762 GMC_2s (c), GMT_2s (t));
1763 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1766 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1771 /* Start new connections if needed */
1772 if (NULL == t->connection_head)
1774 LOG (GNUNET_ERROR_TYPE_DEBUG, " no more connections\n");
1775 GMP_connect (t->peer);
1776 t->cstate = MESH_TUNNEL3_SEARCHING;
1780 /* If not marked as ready, no change is needed */
1781 if (MESH_TUNNEL3_READY != t->cstate)
1784 /* Check if any connection is ready to maintaing cstate */
1785 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1786 if (MESH_CONNECTION_READY == GMC_get_state (aux->c))
1789 t->cstate = MESH_TUNNEL3_WAITING;
1794 * Add a channel to a tunnel.
1797 * @param ch Channel.
1800 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1802 struct MeshTChannel *aux;
1804 GNUNET_assert (NULL != ch);
1806 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1808 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1810 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1815 aux = GNUNET_new (struct MeshTChannel);
1817 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1818 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1820 if (GNUNET_YES == t->destroy)
1822 t->destroy = GNUNET_NO;
1823 LOG (GNUNET_ERROR_TYPE_DEBUG, " undo destroy!\n");
1829 * Remove a channel from a tunnel.
1832 * @param ch Channel.
1835 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1837 struct MeshTChannel *aux;
1839 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1840 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1844 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1845 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1854 * Search for a channel by global ID.
1856 * @param t Tunnel containing the channel.
1857 * @param chid Public channel number.
1859 * @return channel handler, NULL if doesn't exist
1861 struct MeshChannel *
1862 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1864 struct MeshTChannel *iter;
1869 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1871 if (GMCH_get_id (iter->ch) == chid)
1875 return NULL == iter ? NULL : iter->ch;
1880 * Tunnel is empty: destroy it.
1882 * Notifies all connections about the destruction.
1884 * @param t Tunnel to destroy.
1887 GMT_destroy_empty (struct MeshTunnel3 *t)
1889 struct MeshTConnection *iter;
1891 LOG (GNUNET_ERROR_TYPE_DEBUG, "Tunnel empty: destroying scheduled\n");
1892 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1894 GMC_send_destroy (iter->c);
1897 t->cstate = MESH_TUNNEL3_NEW;
1898 t->destroy = GNUNET_YES;
1903 * Destroy tunnel if empty (no more channels).
1905 * @param t Tunnel to destroy if empty.
1908 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1910 if (1 < GMT_count_channels (t))
1913 GMT_destroy_empty (t);
1918 * Destroy the tunnel.
1920 * This function does not generate any warning traffic to clients or peers.
1923 * Cancel messages belonging to this tunnel queued to neighbors.
1924 * Free any allocated resources linked to the tunnel.
1926 * @param t The tunnel to destroy.
1929 GMT_destroy (struct MeshTunnel3 *t)
1931 struct MeshTConnection *iter_c;
1932 struct MeshTConnection *next_c;
1933 struct MeshTChannel *iter_ch;
1934 struct MeshTChannel *next_ch;
1939 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
1941 GNUNET_break (GNUNET_YES ==
1942 GNUNET_CONTAINER_multipeermap_remove (tunnels,
1943 GMP_get_id (t->peer), t));
1945 for (iter_c = t->connection_head; NULL != iter_c; iter_c = next_c)
1947 next_c = iter_c->next;
1948 GMC_destroy (iter_c->c);
1950 for (iter_ch = t->channel_head; NULL != iter_ch; iter_ch = next_ch)
1952 next_ch = iter_ch->next;
1953 GMCH_destroy (iter_ch->ch);
1954 /* Should only happen on shutdown, but it's ok. */
1957 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
1958 GMP_set_tunnel (t->peer, NULL);
1960 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1961 GNUNET_SCHEDULER_cancel (t->rekey_task);
1968 * @brief Use the given path for the tunnel.
1969 * Update the next and prev hops (and RCs).
1970 * (Re)start the path refresh in case the tunnel is locally owned.
1972 * @param t Tunnel to update.
1973 * @param p Path to use.
1975 * @return Connection created.
1977 struct MeshConnection *
1978 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
1980 struct MeshConnection *c;
1981 struct GNUNET_HashCode cid;
1982 unsigned int own_pos;
1984 if (NULL == t || NULL == p)
1990 for (own_pos = 0; own_pos < p->length; own_pos++)
1992 if (p->peers[own_pos] == myid)
1995 if (own_pos > p->length - 1)
2001 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
2002 c = GMC_new (&cid, t, p, own_pos);
2005 /* Path was flawed */
2008 GMT_add_connection (t, c);
2014 * Count established (ready) connections of a tunnel.
2016 * @param t Tunnel on which to count.
2018 * @return Number of connections.
2021 GMT_count_connections (struct MeshTunnel3 *t)
2023 struct MeshTConnection *iter;
2026 for (count = 0, iter = t->connection_head;
2028 iter = iter->next, count++);
2034 * Count channels of a tunnel.
2036 * @param t Tunnel on which to count.
2038 * @return Number of channels.
2041 GMT_count_channels (struct MeshTunnel3 *t)
2043 struct MeshTChannel *iter;
2046 for (count = 0, iter = t->channel_head;
2048 iter = iter->next, count++) /* skip */;
2055 * Get the connectivity state of a tunnel.
2059 * @return Tunnel's connectivity state.
2061 enum MeshTunnel3CState
2062 GMT_get_cstate (struct MeshTunnel3 *t)
2067 return (enum MeshTunnel3CState) -1;
2074 * Get the maximum buffer space for a tunnel towards a local client.
2078 * @return Biggest buffer space offered by any channel in the tunnel.
2081 GMT_get_channels_buffer (struct MeshTunnel3 *t)
2083 struct MeshTChannel *iter;
2084 unsigned int buffer;
2085 unsigned int ch_buf;
2087 if (NULL == t->channel_head)
2089 /* Probably getting buffer for a channel create/handshake. */
2094 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2096 ch_buf = get_channel_buffer (iter);
2097 if (ch_buf > buffer)
2105 * Get the total buffer space for a tunnel for P2P traffic.
2109 * @return Buffer space offered by all connections in the tunnel.
2112 GMT_get_connections_buffer (struct MeshTunnel3 *t)
2114 struct MeshTConnection *iter;
2115 unsigned int buffer;
2118 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2120 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
2124 buffer += get_connection_buffer (iter);
2132 * Get the tunnel's destination.
2136 * @return ID of the destination peer.
2138 const struct GNUNET_PeerIdentity *
2139 GMT_get_destination (struct MeshTunnel3 *t)
2141 return GMP_get_id (t->peer);
2146 * Get the tunnel's next free global channel ID.
2150 * @return GID of a channel free to use.
2153 GMT_get_next_chid (struct MeshTunnel3 *t)
2155 MESH_ChannelNumber chid;
2156 MESH_ChannelNumber mask;
2159 /* Set bit 30 depending on the ID relationship. Bit 31 is always 0 for GID.
2160 * If our ID is bigger or loopback tunnel, start at 0, bit 30 = 0
2161 * If peer's ID is bigger, start at 0x4... bit 30 = 1
2163 result = GNUNET_CRYPTO_cmp_peer_identity (&my_full_id, GMP_get_id (t->peer));
2169 while (NULL != GMT_get_channel (t, t->next_chid))
2171 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
2172 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2173 t->next_chid |= mask;
2175 chid = t->next_chid;
2176 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2177 t->next_chid |= mask;
2184 * Send ACK on one or more channels due to buffer in connections.
2186 * @param t Channel which has some free buffer space.
2189 GMT_unchoke_channels (struct MeshTunnel3 *t)
2191 struct MeshTChannel *iter;
2192 unsigned int buffer;
2193 unsigned int channels = GMT_count_channels (t);
2194 unsigned int choked_n;
2195 struct MeshChannel *choked[channels];
2197 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
2198 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
2199 if (NULL != t->channel_head)
2200 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
2202 /* Get buffer space */
2203 buffer = GMT_get_connections_buffer (t);
2209 /* Count and remember choked channels */
2211 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2213 if (GNUNET_NO == get_channel_allowed (iter))
2215 choked[choked_n++] = iter->ch;
2219 /* Unchoke random channels */
2220 while (0 < buffer && 0 < choked_n)
2222 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2224 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
2227 choked[r] = choked[choked_n];
2233 * Send ACK on one or more connections due to buffer space to the client.
2235 * Iterates all connections of the tunnel and sends ACKs appropriately.
2240 GMT_send_connection_acks (struct MeshTunnel3 *t)
2242 struct MeshTConnection *iter;
2245 uint32_t allow_per_connection;
2247 unsigned int buffer;
2249 LOG (GNUNET_ERROR_TYPE_DEBUG,
2250 "Tunnel send connection ACKs on %s\n",
2259 buffer = GMT_get_channels_buffer (t);
2261 /* Count connections, how many messages are already allowed */
2262 cs = GMT_count_connections (t);
2263 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
2265 allowed += get_connection_allowed (iter);
2268 /* Make sure there is no overflow */
2269 if (allowed > buffer)
2274 /* Authorize connections to send more data */
2275 to_allow = buffer; /* - allowed; */
2277 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
2279 allow_per_connection = to_allow/cs;
2280 to_allow -= allow_per_connection;
2282 if (get_connection_allowed (iter) > 64 / 3)
2286 GMC_allow (iter->c, buffer, GMC_is_origin (iter->c, GNUNET_YES));
2289 GNUNET_break (to_allow == 0);
2294 * Cancel a previously sent message while it's in the queue.
2296 * ONLY can be called before the continuation given to the send function
2297 * is called. Once the continuation is called, the message is no longer in the
2300 * @param q Handle to the queue.
2303 GMT_cancel (struct MeshTunnel3Queue *q)
2308 /* message_sent() will be called and free q */
2310 else if (NULL != q->tqd)
2312 unqueue_data (q->tqd);
2322 * Sends an already built message on a tunnel, encrypting it and
2323 * choosing the best connection.
2325 * @param message Message to send. Function modifies it.
2326 * @param t Tunnel on which this message is transmitted.
2327 * @param force Force the tunnel to take the message (buffer overfill).
2328 * @param cont Continuation to call once message is really sent.
2329 * @param cont_cls Closure for @c cont.
2331 * @return Handle to cancel message. NULL if @c cont is NULL.
2333 struct MeshTunnel3Queue *
2334 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2335 struct MeshTunnel3 *t, int force,
2336 GMT_sent cont, void *cont_cls)
2338 return send_prebuilt_message (message, t, force, cont, cont_cls, NULL);
2343 * Is the tunnel directed towards the local peer?
2347 * @return #GNUNET_YES if it is loopback.
2350 GMT_is_loopback (const struct MeshTunnel3 *t)
2352 return (myid == GMP_get_short_id (t->peer));
2357 * Is the tunnel this path already?
2362 * @return #GNUNET_YES a connection uses this path.
2365 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2367 struct MeshTConnection *iter;
2369 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2370 if (GMC_get_path (iter->c) == p)
2378 * Get a cost of a path for a tunnel considering existing connections.
2381 * @param path Candidate path.
2383 * @return Cost of the path (path length + number of overlapping nodes)
2386 GMT_get_path_cost (const struct MeshTunnel3 *t,
2387 const struct MeshPeerPath *path)
2389 struct MeshTConnection *iter;
2390 const struct MeshPeerPath *aux;
2391 unsigned int overlap;
2399 GNUNET_assert (NULL != t);
2401 for (i = 0; i < path->length; i++)
2403 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2405 aux = GMC_get_path (iter->c);
2409 for (j = 0; j < aux->length; j++)
2411 if (path->peers[i] == aux->peers[j])
2419 return (path->length + overlap) * (path->score * -1);
2424 * Get the static string for the peer this tunnel is directed.
2428 * @return Static string the destination peer's ID.
2431 GMT_2s (const struct MeshTunnel3 *t)
2436 return GMP_2s (t->peer);