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 * Don't try to recover tunnels if shutting down.
227 extern int shutting_down;
231 * Set of all tunnels, in order to trigger a new exchange on rekey.
232 * Indexed by peer's ID.
234 static struct GNUNET_CONTAINER_MultiPeerMap *tunnels;
237 * Default TTL for payload packets.
239 static unsigned long long default_ttl;
244 const static struct GNUNET_CRYPTO_EddsaPrivateKey *my_private_key;
247 * Own ephemeral private key.
249 static struct GNUNET_CRYPTO_EcdhePrivateKey *my_ephemeral_key;
252 * Cached message used to perform a key exchange.
254 static struct GNUNET_MESH_KX_Ephemeral kx_msg;
257 * Task to generate a new ephemeral key.
259 static GNUNET_SCHEDULER_TaskIdentifier rekey_task;
264 static struct GNUNET_TIME_Relative rekey_period;
266 /******************************************************************************/
267 /******************************** STATIC ***********************************/
268 /******************************************************************************/
271 * Get string description for tunnel connectivity state.
273 * @param cs Tunnel state.
275 * @return String representation.
278 cstate2s (enum MeshTunnel3CState cs)
280 static char buf[128];
284 case MESH_TUNNEL3_NEW:
285 return "MESH_TUNNEL3_NEW";
286 case MESH_TUNNEL3_SEARCHING:
287 return "MESH_TUNNEL3_SEARCHING";
288 case MESH_TUNNEL3_WAITING:
289 return "MESH_TUNNEL3_WAITING";
290 case MESH_TUNNEL3_READY:
291 return "MESH_TUNNEL3_READY";
294 sprintf (buf, "%u (UNKNOWN STATE)", cs);
302 * Get string description for tunnel encryption state.
304 * @param es Tunnel state.
306 * @return String representation.
309 estate2s (enum MeshTunnel3EState es)
311 static char buf[128];
315 case MESH_TUNNEL3_KEY_UNINITIALIZED:
316 return "MESH_TUNNEL3_KEY_UNINITIALIZED";
317 case MESH_TUNNEL3_KEY_SENT:
318 return "MESH_TUNNEL3_KEY_SENT";
319 case MESH_TUNNEL3_KEY_PING:
320 return "MESH_TUNNEL3_KEY_PING";
321 case MESH_TUNNEL3_KEY_OK:
322 return "MESH_TUNNEL3_KEY_OK";
325 sprintf (buf, "%u (UNKNOWN STATE)", es);
333 * @brief Check if tunnel is ready to send traffic.
335 * Tunnel must be connected and with encryption correctly set up.
337 * @param t Tunnel to check.
339 * @return #GNUNET_YES if ready, #GNUNET_NO otherwise
342 is_ready (struct MeshTunnel3 *t)
344 return (MESH_TUNNEL3_READY == t->cstate
345 && MESH_TUNNEL3_KEY_OK == t->estate)
346 || GMT_is_loopback (t);
351 * Ephemeral key message purpose size.
353 * @return Size of the part of the ephemeral key message that must be signed.
356 ephemeral_purpose_size (void)
358 return sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
359 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
360 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
361 sizeof (struct GNUNET_CRYPTO_EcdhePublicKey) +
362 sizeof (struct GNUNET_PeerIdentity);
367 * Size of the encrypted part of a ping message.
369 * @return Size of the encrypted part of a ping message.
372 ping_encryption_size (void)
374 return sizeof (struct GNUNET_PeerIdentity) + sizeof (uint32_t);
379 * Get the channel's buffer. ONLY FOR NON-LOOPBACK CHANNELS!!
381 * @param tch Tunnel's channel handle.
383 * @return Amount of messages the channel can still buffer towards the client.
386 get_channel_buffer (const struct MeshTChannel *tch)
390 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
391 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
393 return GMCH_get_buffer (tch->ch, fwd);
398 * Get the channel's allowance status.
400 * @param tch Tunnel's channel handle.
402 * @return #GNUNET_YES if we allowed the client to send data to us.
405 get_channel_allowed (const struct MeshTChannel *tch)
409 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
410 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
412 return GMCH_get_allowed (tch->ch, fwd);
417 * Get the connection's buffer.
419 * @param tc Tunnel's connection handle.
421 * @return Amount of messages the connection can still buffer.
424 get_connection_buffer (const struct MeshTConnection *tc)
428 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
429 fwd = GMC_is_origin (tc->c, GNUNET_YES);
431 return GMC_get_buffer (tc->c, fwd);
436 * Get the connection's allowance.
438 * @param tc Tunnel's connection handle.
440 * @return Amount of messages we have allowed the next peer to send us.
443 get_connection_allowed (const struct MeshTConnection *tc)
447 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
448 fwd = GMC_is_origin (tc->c, GNUNET_YES);
450 return GMC_get_allowed (tc->c, fwd);
455 * Check that a ephemeral key message s well formed and correctly signed.
457 * @param t Tunnel on which the message came.
458 * @param msg The ephemeral key message.
460 * @return GNUNET_OK if message is fine, GNUNET_SYSERR otherwise.
463 check_ephemeral (struct MeshTunnel3 *t,
464 const struct GNUNET_MESH_KX_Ephemeral *msg)
466 /* Check message size */
467 if (ntohs (msg->header.size) != sizeof (struct GNUNET_MESH_KX_Ephemeral))
468 return GNUNET_SYSERR;
470 /* Check signature size */
471 if (ntohl (msg->purpose.size) != ephemeral_purpose_size ())
472 return GNUNET_SYSERR;
475 if (0 != memcmp (&msg->origin_identity,
476 GMP_get_id (t->peer),
477 sizeof (struct GNUNET_PeerIdentity)))
478 return GNUNET_SYSERR;
480 /* Check signature */
482 GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_MESH_KX,
485 &msg->origin_identity.public_key))
486 return GNUNET_SYSERR;
493 * Encrypt data with the tunnel key.
495 * @param t Tunnel whose key to use.
496 * @param dst Destination for the encrypted data.
497 * @param src Source of the plaintext. Can overlap with @c dst.
498 * @param size Size of the plaintext.
499 * @param iv Initialization Vector to use.
502 t_encrypt (struct MeshTunnel3 *t,
503 void *dst, const void *src,
504 size_t size, uint32_t iv)
506 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
508 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->e_key, &iv, sizeof (uint32_t), NULL);
509 return GNUNET_CRYPTO_symmetric_encrypt (src, size, &t->e_key, &siv, dst);
514 * Decrypt data with the tunnel key.
516 * @param t Tunnel whose key to use.
517 * @param dst Destination for the plaintext.
518 * @param src Source of the encrypted data. Can overlap with @c dst.
519 * @param size Size of the encrypted data.
520 * @param iv Initialization Vector to use.
523 t_decrypt (struct MeshTunnel3 *t,
524 void *dst, const void *src,
525 size_t size, uint32_t iv)
527 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
529 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->d_key, &iv, sizeof (uint32_t), NULL);
530 return GNUNET_CRYPTO_symmetric_decrypt (src, size, &t->d_key, &siv, dst);
535 * Create key material by doing ECDH on the local and remote ephemeral keys.
537 * @param key_material Where to store the key material.
538 * @param ephemeral_key Peer's public ephemeral key.
541 derive_key_material (struct GNUNET_HashCode *key_material,
542 const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key)
545 GNUNET_CRYPTO_ecc_ecdh (my_ephemeral_key,
554 * Create a symmetic key from the identities of both ends and the key material
557 * @param key Destination for the generated key.
558 * @param sender ID of the peer that will encrypt with @c key.
559 * @param receiver ID of the peer that will decrypt with @c key.
560 * @param key_material Hash created with ECDH with the ephemeral keys.
563 derive_symmertic (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
564 const struct GNUNET_PeerIdentity *sender,
565 const struct GNUNET_PeerIdentity *receiver,
566 const struct GNUNET_HashCode *key_material)
568 const char salt[] = "MESH kx salt";
570 GNUNET_CRYPTO_kdf (key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
572 key_material, sizeof (struct GNUNET_HashCode),
573 sender, sizeof (struct GNUNET_PeerIdentity),
574 receiver, sizeof (struct GNUNET_PeerIdentity),
579 * Pick a connection on which send the next data message.
581 * @param t Tunnel on which to send the message.
583 * @return The connection on which to send the next message.
585 static struct MeshConnection *
586 tunnel_get_connection (struct MeshTunnel3 *t)
588 struct MeshTConnection *iter;
589 struct MeshConnection *best;
591 unsigned int lowest_q;
593 LOG (GNUNET_ERROR_TYPE_DEBUG, "tunnel_get_connection %s\n", GMP_2s (t->peer));
596 for (iter = t->connection_head; NULL != iter; iter = iter->next)
598 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s: %u\n",
599 GMC_2s (iter->c), GMC_get_state (iter->c));
600 if (MESH_CONNECTION_READY == GMC_get_state (iter->c))
602 qn = GMC_get_qn (iter->c, GMC_is_origin (iter->c, GNUNET_YES));
603 LOG (GNUNET_ERROR_TYPE_DEBUG, " q_n %u, \n", qn);
611 LOG (GNUNET_ERROR_TYPE_DEBUG, " selected: connection %s\n", GMC_2s (best));
617 * Callback called when a queued message is sent.
619 * Calculates the average time and connection packet tracking.
621 * @param cls Closure (TunnelQueue handle).
622 * @param c Connection this message was on.
623 * @param q Connection queue handle (unused).
624 * @param type Type of message sent.
625 * @param fwd Was this a FWD going message?
626 * @param size Size of the message.
629 message_sent (void *cls,
630 struct MeshConnection *c,
631 struct MeshConnectionQueue *q,
632 uint16_t type, int fwd, size_t size)
634 struct MeshTunnel3Queue *qt = cls;
636 GNUNET_assert (NULL != qt->cont);
637 qt->cont (qt->cont_cls, GMC_get_tunnel (c), qt, type, size);
643 * Delete a queued message: either was sent or the channel was destroyed
644 * before the tunnel's key exchange had a chance to finish.
646 * @param tq Queue handle.
649 unqueue_data (struct MeshTunnelDelayed *tq)
651 GNUNET_CONTAINER_DLL_remove (tq->t->tq_head, tq->t->tq_tail, tq);
657 * Cache a message to be sent once tunnel is online.
659 * @param t Tunnel to hold the message.
660 * @param msg Message itself (copy will be made).
662 static struct MeshTunnelDelayed *
663 queue_data (struct MeshTunnel3 *t, const struct GNUNET_MessageHeader *msg)
665 struct MeshTunnelDelayed *tqd;
666 uint16_t size = ntohs (msg->size);
668 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue data on Tunnel %s\n", GMT_2s (t));
670 if (GNUNET_YES == is_ready (t))
676 tqd = GNUNET_malloc (sizeof (struct MeshTunnelDelayed) + size);
679 memcpy (&tqd[1], msg, size);
680 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tqd);
687 * Sends an already built message on a tunnel, encrypting it and
688 * choosing the best connection.
690 * @param message Message to send. Function modifies it.
691 * @param t Tunnel on which this message is transmitted.
692 * @param force Force the tunnel to take the message (buffer overfill).
693 * @param cont Continuation to call once message is really sent.
694 * @param cont_cls Closure for @c cont.
695 * @param existing_q In case this a transmission of previously queued data,
696 * this should be TunnelQueue given to the client.
699 * @return Handle to cancel message. NULL if @c cont is NULL.
701 static struct MeshTunnel3Queue *
702 send_prebuilt_message (const struct GNUNET_MessageHeader *message,
703 struct MeshTunnel3 *t, int force,
704 GMT_sent cont, void *cont_cls,
705 struct MeshTunnel3Queue *existing_q)
707 struct MeshTunnel3Queue *tq;
708 struct MeshConnection *c;
709 struct GNUNET_MESH_Encrypted *msg;
710 size_t size = ntohs (message->size);
711 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
716 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
718 if (GNUNET_NO == is_ready (t))
720 struct MeshTunnelDelayed *tqd;
721 /* A non null existing_q indicates sending of queued data.
722 * Should only happen after tunnel becomes ready.
724 GNUNET_assert (NULL == existing_q);
725 tqd = queue_data (t, message);
728 tq = GNUNET_new (struct MeshTunnel3Queue);
732 tq->cont_cls = cont_cls;
736 GNUNET_assert (GNUNET_NO == GMT_is_loopback (t));
738 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
739 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
740 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
742 GNUNET_assert (t_encrypt (t, &msg[1], message, size, iv) == size);
743 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + size);
744 c = tunnel_get_connection (t);
747 if (GNUNET_YES == t->destroy || MESH_TUNNEL3_SEARCHING != t->cstate)
754 type = ntohs (message->type);
757 case GNUNET_MESSAGE_TYPE_MESH_DATA:
758 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
759 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
760 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
761 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
762 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
763 msg->cid = *GMC_get_id (c);
764 msg->ttl = htonl (default_ttl);
767 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
772 fwd = GMC_is_origin (c, GNUNET_YES);
776 (void) GMC_send_prebuilt_message (&msg->header, c, fwd, force, NULL, NULL);
779 if (NULL == existing_q)
781 tq = GNUNET_new (struct MeshTunnel3Queue); /* FIXME valgrind: leak*/
788 tq->cq = GMC_send_prebuilt_message (&msg->header, c, fwd, force,
791 tq->cont_cls = cont_cls;
798 * Send all cached messages that we can, tunnel is online.
800 * @param t Tunnel that holds the messages. Cannot be loopback.
803 send_queued_data (struct MeshTunnel3 *t)
805 struct MeshTunnelDelayed *tqd;
806 struct MeshTunnelDelayed *next;
809 LOG (GNUNET_ERROR_TYPE_DEBUG,
810 "GMT_send_queued_data on tunnel %s\n",
813 if (GMT_is_loopback (t))
819 if (GNUNET_NO == is_ready (t))
821 LOG (GNUNET_ERROR_TYPE_DEBUG, " not ready yet: %s/%s\n",
822 estate2s (t->estate), cstate2s (t->cstate));
826 room = GMT_get_connections_buffer (t);
827 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
828 LOG (GNUNET_ERROR_TYPE_DEBUG, " tq head: %p\n", t->tq_head);
829 for (tqd = t->tq_head; NULL != tqd && room > 0; tqd = next)
831 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending queued data\n");
834 send_prebuilt_message ((struct GNUNET_MessageHeader *) &tqd[1],
836 NULL != tqd->tq ? tqd->tq->cont : NULL,
837 NULL != tqd->tq ? tqd->tq->cont_cls : NULL,
841 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_send_queued_data end\n", GMP_2s (t->peer));
846 * Sends key exchange message on a tunnel, choosing the best connection.
847 * Should not be called on loopback tunnels.
849 * @param t Tunnel on which this message is transmitted.
850 * @param message Message to send. Function modifies it.
853 send_kx (struct MeshTunnel3 *t,
854 const struct GNUNET_MessageHeader *message)
856 struct MeshConnection *c;
857 struct GNUNET_MESH_KX *msg;
858 size_t size = ntohs (message->size);
859 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
863 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
865 /* Avoid loopback. */
866 if (GMT_is_loopback (t))
868 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
873 /* Must have a connection. */
874 if (NULL == t->connection_head)
876 GNUNET_break (MESH_TUNNEL3_SEARCHING == t->cstate);
881 msg = (struct GNUNET_MESH_KX *) cbuf;
882 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
883 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
884 c = tunnel_get_connection (t);
887 GNUNET_break (GNUNET_YES == t->destroy || MESH_TUNNEL3_READY != t->cstate);
891 type = ntohs (message->type);
894 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
895 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
896 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
897 msg->reserved = htonl (0);
898 memcpy (&msg[1], message, size);
901 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
906 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
907 /* TODO save handle and cancel in case of a unneeded retransmission */
908 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
913 * Send the ephemeral key on a tunnel.
915 * @param t Tunnel on which to send the key.
918 send_ephemeral (struct MeshTunnel3 *t)
920 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
922 kx_msg.sender_status = htonl (t->estate);
923 send_kx (t, &kx_msg.header);
927 * Send a ping message on a tunnel.
929 * @param t Tunnel on which to send the ping.
932 send_ping (struct MeshTunnel3 *t)
934 struct GNUNET_MESH_KX_Ping msg;
936 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
937 msg.header.size = htons (sizeof (msg));
938 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
939 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
940 msg.target = *GMP_get_id (t->peer);
941 msg.nonce = t->kx_ctx->challenge;
943 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
944 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&msg.target));
945 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
946 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
947 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg.target));
949 send_kx (t, &msg.header);
954 * Send a pong message on a tunnel.
956 * @param t Tunnel on which to send the pong.
957 * @param challenge Value sent in the ping that we have to send back.
960 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
962 struct GNUNET_MESH_KX_Pong msg;
964 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
965 msg.header.size = htons (sizeof (msg));
966 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
967 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
968 msg.nonce = challenge;
969 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
970 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
971 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
973 send_kx (t, &msg.header);
978 * Initiate a rekey with the remote peer.
980 * @param cls Closure (tunnel).
981 * @param tc TaskContext.
984 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
986 struct MeshTunnel3 *t = cls;
988 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
990 LOG (GNUNET_ERROR_TYPE_DEBUG, "Re-key Tunnel %s\n", GMT_2s (t));
991 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
994 if (NULL == t->kx_ctx)
996 LOG (GNUNET_ERROR_TYPE_DEBUG, " new kx ctx\n");
997 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
998 t->kx_ctx->challenge =
999 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
1000 t->kx_ctx->d_key_old = t->d_key;
1001 LOG (GNUNET_ERROR_TYPE_DEBUG, " new challenge for %s: %u\n",
1002 GMT_2s (t), t->kx_ctx->challenge);
1007 case MESH_TUNNEL3_KEY_UNINITIALIZED:
1008 t->estate = MESH_TUNNEL3_KEY_SENT;
1010 case MESH_TUNNEL3_KEY_SENT:
1012 case MESH_TUNNEL3_KEY_PING:
1013 case MESH_TUNNEL3_KEY_OK:
1015 t->estate = MESH_TUNNEL3_KEY_PING;
1018 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->estate);
1021 LOG (GNUNET_ERROR_TYPE_DEBUG, " next call in %s\n",
1022 GNUNET_STRINGS_relative_time_to_string (REKEY_WAIT, GNUNET_YES));
1023 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
1028 * Out ephemeral key has changed, create new session key on all tunnels.
1030 * @param cls Closure (size of the hashmap).
1031 * @param key Current public key.
1032 * @param value Value in the hash map (tunnel).
1034 * @return #GNUNET_YES, so we should continue to iterate,
1037 rekey_iterator (void *cls,
1038 const struct GNUNET_PeerIdentity *key,
1041 struct MeshTunnel3 *t = value;
1042 struct GNUNET_TIME_Relative delay;
1043 long n = (long) cls;
1046 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1049 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
1050 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
1051 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
1058 * Create a new ephemeral key and key message, schedule next rekeying.
1060 * @param cls Closure (unused).
1061 * @param tc TaskContext.
1064 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1066 struct GNUNET_TIME_Absolute time;
1069 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1071 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
1074 GNUNET_free_non_null (my_ephemeral_key);
1075 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
1077 time = GNUNET_TIME_absolute_get ();
1078 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
1079 time = GNUNET_TIME_absolute_add (time, rekey_period);
1080 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
1081 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
1082 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
1084 GNUNET_assert (GNUNET_OK ==
1085 GNUNET_CRYPTO_eddsa_sign (my_private_key,
1087 &kx_msg.signature));
1089 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
1090 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
1092 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
1097 * Called only on shutdown, destroy every tunnel.
1099 * @param cls Closure (unused).
1100 * @param key Current public key.
1101 * @param value Value in the hash map (tunnel).
1103 * @return #GNUNET_YES, so we should continue to iterate,
1106 destroy_iterator (void *cls,
1107 const struct GNUNET_PeerIdentity *key,
1110 struct MeshTunnel3 *t = value;
1118 * Demultiplex data per channel and call appropriate channel handler.
1120 * @param t Tunnel on which the data came.
1121 * @param msg Data message.
1122 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1123 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1124 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1125 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1128 handle_data (struct MeshTunnel3 *t,
1129 const struct GNUNET_MESH_Data *msg,
1132 struct MeshChannel *ch;
1136 size = ntohs (msg->header.size);
1138 sizeof (struct GNUNET_MESH_Data) +
1139 sizeof (struct GNUNET_MessageHeader))
1144 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
1145 GM_m2s (ntohs (msg[1].header.type)));
1148 ch = GMT_get_channel (t, ntohl (msg->chid));
1151 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
1153 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1158 GMCH_handle_data (ch, msg, fwd);
1163 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
1165 * @param t Tunnel on which the DATA ACK came.
1166 * @param msg DATA ACK message.
1167 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1168 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1169 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1170 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1173 handle_data_ack (struct MeshTunnel3 *t,
1174 const struct GNUNET_MESH_DataACK *msg,
1177 struct MeshChannel *ch;
1181 size = ntohs (msg->header.size);
1182 if (size != sizeof (struct GNUNET_MESH_DataACK))
1189 ch = GMT_get_channel (t, ntohl (msg->chid));
1192 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
1194 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1199 GMCH_handle_data_ack (ch, msg, fwd);
1204 * Handle channel create.
1206 * @param t Tunnel on which the data came.
1207 * @param msg Data message.
1210 handle_ch_create (struct MeshTunnel3 *t,
1211 const struct GNUNET_MESH_ChannelCreate *msg)
1213 struct MeshChannel *ch;
1217 size = ntohs (msg->header.size);
1218 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
1225 ch = GMT_get_channel (t, ntohl (msg->chid));
1226 if (NULL != ch && ! GMT_is_loopback (t))
1228 /* Probably a retransmission, safe to ignore */
1229 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
1233 ch = GMCH_handle_create (t, msg);
1236 GMT_add_channel (t, ch);
1242 * Handle channel NACK: check correctness and call channel handler for NACKs.
1244 * @param t Tunnel on which the NACK came.
1245 * @param msg NACK message.
1248 handle_ch_nack (struct MeshTunnel3 *t,
1249 const struct GNUNET_MESH_ChannelManage *msg)
1251 struct MeshChannel *ch;
1255 size = ntohs (msg->header.size);
1256 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1263 ch = GMT_get_channel (t, ntohl (msg->chid));
1266 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
1268 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1273 GMCH_handle_nack (ch);
1278 * Handle a CHANNEL ACK (SYNACK/ACK).
1280 * @param t Tunnel on which the CHANNEL ACK came.
1281 * @param msg CHANNEL ACK message.
1282 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1283 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1284 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1285 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1288 handle_ch_ack (struct MeshTunnel3 *t,
1289 const struct GNUNET_MESH_ChannelManage *msg,
1292 struct MeshChannel *ch;
1296 size = ntohs (msg->header.size);
1297 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1304 ch = GMT_get_channel (t, ntohl (msg->chid));
1307 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1309 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1314 GMCH_handle_ack (ch, msg, fwd);
1320 * Handle a channel destruction message.
1322 * @param t Tunnel on which the message came.
1323 * @param msg Channel destroy message.
1324 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1325 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1326 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1327 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1330 handle_ch_destroy (struct MeshTunnel3 *t,
1331 const struct GNUNET_MESH_ChannelManage *msg,
1334 struct MeshChannel *ch;
1338 size = ntohs (msg->header.size);
1339 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1346 ch = GMT_get_channel (t, ntohl (msg->chid));
1349 /* Probably a retransmission, safe to ignore */
1353 GMCH_handle_destroy (ch, msg, fwd);
1358 * The peer's ephemeral key has changed: update the symmetrical keys.
1360 * @param t Tunnel this message came on.
1361 * @param msg Key eXchange message.
1364 handle_ephemeral (struct MeshTunnel3 *t,
1365 const struct GNUNET_MESH_KX_Ephemeral *msg)
1367 struct GNUNET_HashCode km;
1368 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1370 if (GNUNET_OK != check_ephemeral (t, msg))
1372 GNUNET_break_op (0);
1375 derive_key_material (&km, &msg->ephemeral_key);
1376 LOG (GNUNET_ERROR_TYPE_DEBUG, " km is %s\n", GNUNET_h2s (&km));
1377 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1378 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1379 if (MESH_TUNNEL3_KEY_SENT == t->estate)
1381 LOG (GNUNET_ERROR_TYPE_DEBUG, " our key was sent, send ping\n");
1383 t->estate = MESH_TUNNEL3_KEY_PING;
1389 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1390 * Answer with by retransmitting the challenge with the "opposite" key.
1392 * @param t Tunnel this message came on.
1393 * @param msg Key eXchange Ping message.
1396 handle_ping (struct MeshTunnel3 *t,
1397 const struct GNUNET_MESH_KX_Ping *msg)
1399 struct GNUNET_MESH_KX_Ping res;
1401 if (ntohs (msg->header.size) != sizeof (res))
1403 GNUNET_break_op (0);
1407 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1408 t_decrypt (t, &res.target, &msg->target, ping_encryption_size (), msg->iv);
1409 if (0 != memcmp (&my_full_id, &res.target, sizeof (my_full_id)))
1411 GNUNET_break_op (0);
1412 LOG (GNUNET_ERROR_TYPE_DEBUG, " e got %u\n", msg->nonce);
1413 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg->target));
1414 LOG (GNUNET_ERROR_TYPE_DEBUG, " got %u\n", res.nonce);
1415 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&res.target));
1419 send_pong (t, res.nonce);
1424 * Peer has answer to our challenge.
1425 * If answer is successful, consider the key exchange finished and clean
1426 * up all related state.
1428 * @param t Tunnel this message came on.
1429 * @param msg Key eXchange Pong message.
1432 handle_pong (struct MeshTunnel3 *t,
1433 const struct GNUNET_MESH_KX_Pong *msg)
1437 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1438 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1440 GNUNET_STATISTICS_update (stats, "# duplicate PONG messages", 1, GNUNET_NO);
1443 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1445 if (challenge != t->kx_ctx->challenge)
1447 LOG (GNUNET_ERROR_TYPE_DEBUG,
1448 "Wrong PONG challenge: %u (e: %u). Expected: %u.\n",
1449 challenge, msg->nonce, t->kx_ctx->challenge);
1450 GNUNET_break_op (0);
1453 GNUNET_SCHEDULER_cancel (t->rekey_task);
1454 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1455 GNUNET_free (t->kx_ctx);
1457 GMT_change_estate (t, MESH_TUNNEL3_KEY_OK);
1462 * Demultiplex by message type and call appropriate handler for a message
1463 * towards a channel of a local tunnel.
1465 * @param t Tunnel this message came on.
1466 * @param msgh Message header.
1467 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1468 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1469 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1470 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1473 handle_decrypted (struct MeshTunnel3 *t,
1474 const struct GNUNET_MessageHeader *msgh,
1479 type = ntohs (msgh->type);
1480 LOG (GNUNET_ERROR_TYPE_DEBUG,
1481 "Got a %s message!\n",
1486 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1487 /* Don't send hop ACK, wait for client to ACK */
1488 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1491 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1492 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1495 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1496 handle_ch_create (t,
1497 (struct GNUNET_MESH_ChannelCreate *) msgh);
1500 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1502 (struct GNUNET_MESH_ChannelManage *) msgh);
1505 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1507 (struct GNUNET_MESH_ChannelManage *) msgh,
1511 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1512 handle_ch_destroy (t,
1513 (struct GNUNET_MESH_ChannelManage *) msgh,
1518 GNUNET_break_op (0);
1519 LOG (GNUNET_ERROR_TYPE_DEBUG,
1520 "end-to-end message not known (%u)\n",
1521 ntohs (msgh->type));
1525 /******************************************************************************/
1526 /******************************** API ***********************************/
1527 /******************************************************************************/
1530 * Decrypt and demultiplex by message type. Call appropriate handler
1531 * for every message.
1533 * @param t Tunnel this message came on.
1534 * @param msg Encrypted message.
1537 GMT_handle_encrypted (struct MeshTunnel3 *t,
1538 const struct GNUNET_MESH_Encrypted *msg)
1540 size_t size = ntohs (msg->header.size);
1541 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1542 size_t decrypted_size;
1543 char cbuf [payload_size];
1544 struct GNUNET_MessageHeader *msgh;
1547 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1549 while (off < decrypted_size)
1551 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1552 handle_decrypted (t, msgh, GNUNET_SYSERR);
1553 off += ntohs (msgh->size);
1559 * Demultiplex an encapsulated KX message by message type.
1561 * @param t Tunnel on which the message came.
1562 * @param message Payload of KX message.
1565 GMT_handle_kx (struct MeshTunnel3 *t,
1566 const struct GNUNET_MessageHeader *message)
1570 type = ntohs (message->type);
1571 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1574 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1575 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1578 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1579 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1582 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1583 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1587 GNUNET_break_op (0);
1588 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1594 * Initialize the tunnel subsystem.
1596 * @param c Configuration handle.
1597 * @param key ECC private key, to derive all other keys and do crypto.
1600 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1601 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1603 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1605 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1608 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1609 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1613 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1616 rekey_period = GNUNET_TIME_UNIT_DAYS;
1619 my_private_key = key;
1620 kx_msg.header.size = htons (sizeof (kx_msg));
1621 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1622 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1623 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1624 kx_msg.origin_identity = my_full_id;
1625 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1627 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1632 * Shut down the tunnel subsystem.
1637 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1639 GNUNET_SCHEDULER_cancel (rekey_task);
1640 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1642 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &destroy_iterator, NULL);
1643 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1650 * @param destination Peer this tunnel is towards.
1652 struct MeshTunnel3 *
1653 GMT_new (struct MeshPeer *destination)
1655 struct MeshTunnel3 *t;
1657 t = GNUNET_new (struct MeshTunnel3);
1659 t->peer = destination;
1662 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1663 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1674 * Change the tunnel's connection state.
1676 * @param t Tunnel whose connection state to change.
1677 * @param cstate New connection state.
1680 GMT_change_cstate (struct MeshTunnel3* t, enum MeshTunnel3CState cstate)
1684 LOG (GNUNET_ERROR_TYPE_DEBUG,
1685 "Tunnel %s cstate was %s\n",
1686 GMP_2s (t->peer), cstate2s (t->cstate));
1687 LOG (GNUNET_ERROR_TYPE_DEBUG,
1688 "Tunnel %s cstate is now %s\n",
1689 GMP_2s (t->peer), cstate2s (cstate));
1690 if (myid != GMP_get_short_id (t->peer) &&
1691 MESH_TUNNEL3_READY != t->cstate &&
1692 MESH_TUNNEL3_READY == cstate)
1695 if (MESH_TUNNEL3_KEY_OK == t->estate)
1697 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered send queued data\n");
1698 send_queued_data (t);
1700 else if (MESH_TUNNEL3_KEY_UNINITIALIZED == t->estate)
1702 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1703 rekey_tunnel (t, NULL);
1708 if (MESH_TUNNEL3_READY == cstate && 3 <= GMT_count_connections (t))
1710 GMP_stop_search (t->peer);
1715 * Change the tunnel encryption state.
1717 * @param t Tunnel whose encryption state to change.
1718 * @param state New encryption state.
1721 GMT_change_estate (struct MeshTunnel3* t, enum MeshTunnel3EState state)
1725 LOG (GNUNET_ERROR_TYPE_DEBUG,
1726 "Tunnel %s estate was %s\n",
1727 GMP_2s (t->peer), estate2s (t->estate));
1728 LOG (GNUNET_ERROR_TYPE_DEBUG,
1729 "Tunnel %s estate is now %s\n",
1730 GMP_2s (t->peer), estate2s (state));
1731 if (myid != GMP_get_short_id (t->peer) &&
1732 MESH_TUNNEL3_KEY_OK != t->estate && MESH_TUNNEL3_KEY_OK == state)
1735 send_queued_data (t);
1743 * Add a connection to a tunnel.
1746 * @param c Connection.
1749 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1751 struct MeshTConnection *aux;
1753 GNUNET_assert (NULL != c);
1755 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1759 aux = GNUNET_new (struct MeshTConnection);
1761 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1766 * Mark a path as no longer valid for this tunnel: has been tried and failed.
1768 * @param t Tunnel to update.
1769 * @param path Invalid path to remove. Is destroyed after removal.
1772 GMT_remove_path (struct MeshTunnel3 *t, struct MeshPeerPath *path)
1774 GMP_remove_path (t->peer, path);
1779 * Remove a connection from a tunnel.
1782 * @param c Connection.
1785 GMT_remove_connection (struct MeshTunnel3 *t,
1786 struct MeshConnection *c)
1788 struct MeshTConnection *aux;
1789 struct MeshTConnection *next;
1791 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing connection %s from tunnel %s\n",
1792 GMC_2s (c), GMT_2s (t));
1793 for (aux = t->connection_head; aux != NULL; aux = next)
1798 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1803 /* Start new connections if needed */
1804 if (NULL == t->connection_head
1805 && GNUNET_NO == t->destroy
1806 && GNUNET_NO == shutting_down)
1808 LOG (GNUNET_ERROR_TYPE_DEBUG, " no more connections, getting new ones\n");
1809 GMP_connect (t->peer);
1810 t->cstate = MESH_TUNNEL3_SEARCHING;
1814 /* If not marked as ready, no change is needed */
1815 if (MESH_TUNNEL3_READY != t->cstate)
1818 /* Check if any connection is ready to maintaing cstate */
1819 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1820 if (MESH_CONNECTION_READY == GMC_get_state (aux->c))
1823 t->cstate = MESH_TUNNEL3_WAITING;
1828 * Add a channel to a tunnel.
1831 * @param ch Channel.
1834 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1836 struct MeshTChannel *aux;
1838 GNUNET_assert (NULL != ch);
1840 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1842 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1844 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1849 aux = GNUNET_new (struct MeshTChannel);
1851 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1852 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1854 if (GNUNET_YES == t->destroy)
1856 t->destroy = GNUNET_NO;
1857 LOG (GNUNET_ERROR_TYPE_DEBUG, " undo destroy!\n");
1863 * Remove a channel from a tunnel.
1866 * @param ch Channel.
1869 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1871 struct MeshTChannel *aux;
1873 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1874 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1878 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1879 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1888 * Search for a channel by global ID.
1890 * @param t Tunnel containing the channel.
1891 * @param chid Public channel number.
1893 * @return channel handler, NULL if doesn't exist
1895 struct MeshChannel *
1896 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1898 struct MeshTChannel *iter;
1903 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1905 if (GMCH_get_id (iter->ch) == chid)
1909 return NULL == iter ? NULL : iter->ch;
1914 * Tunnel is empty: destroy it.
1916 * Notifies all connections about the destruction.
1918 * @param t Tunnel to destroy.
1921 GMT_destroy_empty (struct MeshTunnel3 *t)
1923 struct MeshTConnection *iter;
1925 LOG (GNUNET_ERROR_TYPE_DEBUG, "Tunnel %s empty: destroying scheduled\n",
1927 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1929 GMC_send_destroy (iter->c);
1932 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1934 t->estate = MESH_TUNNEL3_KEY_UNINITIALIZED;
1935 GNUNET_SCHEDULER_cancel (t->rekey_task);
1936 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1937 GNUNET_free (t->kx_ctx);
1940 t->cstate = MESH_TUNNEL3_NEW;
1941 t->destroy = GNUNET_YES;
1946 * Destroy tunnel if empty (no more channels).
1948 * @param t Tunnel to destroy if empty.
1951 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1953 if (1 < GMT_count_channels (t))
1956 GMT_destroy_empty (t);
1961 * Destroy the tunnel.
1963 * This function does not generate any warning traffic to clients or peers.
1966 * Cancel messages belonging to this tunnel queued to neighbors.
1967 * Free any allocated resources linked to the tunnel.
1969 * @param t The tunnel to destroy.
1972 GMT_destroy (struct MeshTunnel3 *t)
1974 struct MeshTConnection *iter_c;
1975 struct MeshTConnection *next_c;
1976 struct MeshTChannel *iter_ch;
1977 struct MeshTChannel *next_ch;
1984 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
1986 GNUNET_break (GNUNET_YES ==
1987 GNUNET_CONTAINER_multipeermap_remove (tunnels,
1988 GMP_get_id (t->peer), t));
1990 for (iter_c = t->connection_head; NULL != iter_c; iter_c = next_c)
1992 next_c = iter_c->next;
1993 GMC_destroy (iter_c->c);
1995 for (iter_ch = t->channel_head; NULL != iter_ch; iter_ch = next_ch)
1997 next_ch = iter_ch->next;
1998 GMCH_destroy (iter_ch->ch);
1999 /* Should only happen on shutdown, but it's ok. */
2002 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
2003 GMP_set_tunnel (t->peer, NULL);
2005 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
2006 GNUNET_SCHEDULER_cancel (t->rekey_task);
2013 * @brief Use the given path for the tunnel.
2014 * Update the next and prev hops (and RCs).
2015 * (Re)start the path refresh in case the tunnel is locally owned.
2017 * @param t Tunnel to update.
2018 * @param p Path to use.
2020 * @return Connection created.
2022 struct MeshConnection *
2023 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
2025 struct MeshConnection *c;
2026 struct GNUNET_HashCode cid;
2027 unsigned int own_pos;
2029 if (NULL == t || NULL == p)
2035 for (own_pos = 0; own_pos < p->length; own_pos++)
2037 if (p->peers[own_pos] == myid)
2040 if (own_pos > p->length - 1)
2042 GNUNET_break_op (0);
2046 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
2047 c = GMC_new (&cid, t, p, own_pos);
2050 /* Path was flawed */
2053 GMT_add_connection (t, c);
2059 * Count established (ready) connections of a tunnel.
2061 * @param t Tunnel on which to count.
2063 * @return Number of connections.
2066 GMT_count_connections (struct MeshTunnel3 *t)
2068 struct MeshTConnection *iter;
2071 for (count = 0, iter = t->connection_head;
2073 iter = iter->next, count++);
2079 * Count channels of a tunnel.
2081 * @param t Tunnel on which to count.
2083 * @return Number of channels.
2086 GMT_count_channels (struct MeshTunnel3 *t)
2088 struct MeshTChannel *iter;
2091 for (count = 0, iter = t->channel_head;
2093 iter = iter->next, count++) /* skip */;
2100 * Get the connectivity state of a tunnel.
2104 * @return Tunnel's connectivity state.
2106 enum MeshTunnel3CState
2107 GMT_get_cstate (struct MeshTunnel3 *t)
2112 return (enum MeshTunnel3CState) -1;
2119 * Get the maximum buffer space for a tunnel towards a local client.
2123 * @return Biggest buffer space offered by any channel in the tunnel.
2126 GMT_get_channels_buffer (struct MeshTunnel3 *t)
2128 struct MeshTChannel *iter;
2129 unsigned int buffer;
2130 unsigned int ch_buf;
2132 if (NULL == t->channel_head)
2134 /* Probably getting buffer for a channel create/handshake. */
2139 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2141 ch_buf = get_channel_buffer (iter);
2142 if (ch_buf > buffer)
2150 * Get the total buffer space for a tunnel for P2P traffic.
2154 * @return Buffer space offered by all connections in the tunnel.
2157 GMT_get_connections_buffer (struct MeshTunnel3 *t)
2159 struct MeshTConnection *iter;
2160 unsigned int buffer;
2163 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2165 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
2169 buffer += get_connection_buffer (iter);
2177 * Get the tunnel's destination.
2181 * @return ID of the destination peer.
2183 const struct GNUNET_PeerIdentity *
2184 GMT_get_destination (struct MeshTunnel3 *t)
2186 return GMP_get_id (t->peer);
2191 * Get the tunnel's next free global channel ID.
2195 * @return GID of a channel free to use.
2198 GMT_get_next_chid (struct MeshTunnel3 *t)
2200 MESH_ChannelNumber chid;
2201 MESH_ChannelNumber mask;
2204 /* Set bit 30 depending on the ID relationship. Bit 31 is always 0 for GID.
2205 * If our ID is bigger or loopback tunnel, start at 0, bit 30 = 0
2206 * If peer's ID is bigger, start at 0x4... bit 30 = 1
2208 result = GNUNET_CRYPTO_cmp_peer_identity (&my_full_id, GMP_get_id (t->peer));
2214 while (NULL != GMT_get_channel (t, t->next_chid))
2216 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
2217 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2218 t->next_chid |= mask;
2220 chid = t->next_chid;
2221 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2222 t->next_chid |= mask;
2229 * Send ACK on one or more channels due to buffer in connections.
2231 * @param t Channel which has some free buffer space.
2234 GMT_unchoke_channels (struct MeshTunnel3 *t)
2236 struct MeshTChannel *iter;
2237 unsigned int buffer;
2238 unsigned int channels = GMT_count_channels (t);
2239 unsigned int choked_n;
2240 struct MeshChannel *choked[channels];
2242 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
2243 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
2244 if (NULL != t->channel_head)
2245 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
2247 /* Get buffer space */
2248 buffer = GMT_get_connections_buffer (t);
2254 /* Count and remember choked channels */
2256 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2258 if (GNUNET_NO == get_channel_allowed (iter))
2260 choked[choked_n++] = iter->ch;
2264 /* Unchoke random channels */
2265 while (0 < buffer && 0 < choked_n)
2267 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2269 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
2272 choked[r] = choked[choked_n];
2278 * Send ACK on one or more connections due to buffer space to the client.
2280 * Iterates all connections of the tunnel and sends ACKs appropriately.
2285 GMT_send_connection_acks (struct MeshTunnel3 *t)
2287 struct MeshTConnection *iter;
2290 uint32_t allow_per_connection;
2292 unsigned int buffer;
2294 LOG (GNUNET_ERROR_TYPE_DEBUG,
2295 "Tunnel send connection ACKs on %s\n",
2304 buffer = GMT_get_channels_buffer (t);
2306 /* Count connections, how many messages are already allowed */
2307 cs = GMT_count_connections (t);
2308 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
2310 allowed += get_connection_allowed (iter);
2313 /* Make sure there is no overflow */
2314 if (allowed > buffer)
2319 /* Authorize connections to send more data */
2320 to_allow = buffer; /* - allowed; */
2322 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
2324 allow_per_connection = to_allow/cs;
2325 to_allow -= allow_per_connection;
2327 if (get_connection_allowed (iter) > 64 / 3)
2331 GMC_allow (iter->c, buffer, GMC_is_origin (iter->c, GNUNET_YES));
2334 GNUNET_break (to_allow == 0);
2339 * Cancel a previously sent message while it's in the queue.
2341 * ONLY can be called before the continuation given to the send function
2342 * is called. Once the continuation is called, the message is no longer in the
2345 * @param q Handle to the queue.
2348 GMT_cancel (struct MeshTunnel3Queue *q)
2353 /* message_sent() will be called and free q */
2355 else if (NULL != q->tqd)
2357 unqueue_data (q->tqd);
2367 * Sends an already built message on a tunnel, encrypting it and
2368 * choosing the best connection.
2370 * @param message Message to send. Function modifies it.
2371 * @param t Tunnel on which this message is transmitted.
2372 * @param force Force the tunnel to take the message (buffer overfill).
2373 * @param cont Continuation to call once message is really sent.
2374 * @param cont_cls Closure for @c cont.
2376 * @return Handle to cancel message. NULL if @c cont is NULL.
2378 struct MeshTunnel3Queue *
2379 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2380 struct MeshTunnel3 *t, int force,
2381 GMT_sent cont, void *cont_cls)
2383 return send_prebuilt_message (message, t, force, cont, cont_cls, NULL);
2388 * Is the tunnel directed towards the local peer?
2392 * @return #GNUNET_YES if it is loopback.
2395 GMT_is_loopback (const struct MeshTunnel3 *t)
2397 return (myid == GMP_get_short_id (t->peer));
2402 * Is the tunnel this path already?
2407 * @return #GNUNET_YES a connection uses this path.
2410 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2412 struct MeshTConnection *iter;
2414 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2415 if (GMC_get_path (iter->c) == p)
2423 * Get a cost of a path for a tunnel considering existing connections.
2426 * @param path Candidate path.
2428 * @return Cost of the path (path length + number of overlapping nodes)
2431 GMT_get_path_cost (const struct MeshTunnel3 *t,
2432 const struct MeshPeerPath *path)
2434 struct MeshTConnection *iter;
2435 const struct MeshPeerPath *aux;
2436 unsigned int overlap;
2444 GNUNET_assert (NULL != t);
2446 for (i = 0; i < path->length; i++)
2448 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2450 aux = GMC_get_path (iter->c);
2454 for (j = 0; j < aux->length; j++)
2456 if (path->peers[i] == aux->peers[j])
2464 return (path->length + overlap) * (path->score * -1);
2469 * Get the static string for the peer this tunnel is directed.
2473 * @return Static string the destination peer's ID.
2476 GMT_2s (const struct MeshTunnel3 *t)
2481 return GMP_2s (t->peer);
2486 * Log all possible info about the tunnel state.
2488 * @param t Tunnel to debug.
2491 GMT_debug (const struct MeshTunnel3 *t)
2493 struct MeshTChannel *iterch;
2494 struct MeshTConnection *iterc;
2496 LOG (GNUNET_ERROR_TYPE_DEBUG, "DEBUG TUNNEL TOWARDS %s\n", GMT_2s (t));
2497 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate %s, estate %s\n",
2498 cstate2s (t->cstate), estate2s (t->estate));
2499 LOG (GNUNET_ERROR_TYPE_DEBUG, " kx_ctx %p, rekey_task %u\n",
2500 t->kx_ctx, t->rekey_task);
2501 LOG (GNUNET_ERROR_TYPE_DEBUG, " tq_head %p, tq_tail %p\n",
2502 t->tq_head, t->tq_tail);
2503 LOG (GNUNET_ERROR_TYPE_DEBUG, " destroy %u\n", t->destroy);
2505 LOG (GNUNET_ERROR_TYPE_DEBUG, " channels:\n");
2506 for (iterch = t->channel_head; NULL != iterch; iterch = iterch->next)
2508 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %s\n", GMCH_2s (iterch->ch));
2511 LOG (GNUNET_ERROR_TYPE_DEBUG, " connections:\n");
2512 for (iterc = t->connection_head; NULL != iterc; iterc = iterc->next)
2514 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %s [%u] buf: %u/%u (qn %u/%u)\n",
2515 GMC_2s (iterc->c), GMC_get_state (iterc->c),
2516 GMC_get_buffer (iterc->c, GNUNET_YES),
2517 GMC_get_buffer (iterc->c, GNUNET_NO),
2518 GMC_get_qn (iterc->c, GNUNET_YES),
2519 GMC_get_qn (iterc->c, GNUNET_NO));
2522 LOG (GNUNET_ERROR_TYPE_DEBUG, "DEBUG TUNNEL END\n");