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 msg->cid = *GMC_get_id (c);
763 msg->ttl = htonl (default_ttl);
766 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
771 fwd = GMC_is_origin (c, GNUNET_YES);
775 (void) GMC_send_prebuilt_message (&msg->header, c, fwd, force, NULL, NULL);
778 if (NULL == existing_q)
780 tq = GNUNET_new (struct MeshTunnel3Queue); /* FIXME valgrind: leak*/
787 tq->cq = GMC_send_prebuilt_message (&msg->header, c, fwd, force,
790 tq->cont_cls = cont_cls;
797 * Send all cached messages that we can, tunnel is online.
799 * @param t Tunnel that holds the messages. Cannot be loopback.
802 send_queued_data (struct MeshTunnel3 *t)
804 struct MeshTunnelDelayed *tqd;
805 struct MeshTunnelDelayed *next;
808 LOG (GNUNET_ERROR_TYPE_DEBUG,
809 "GMT_send_queued_data on tunnel %s\n",
812 if (GMT_is_loopback (t))
818 if (GNUNET_NO == is_ready (t))
820 LOG (GNUNET_ERROR_TYPE_DEBUG, " not ready yet: %s/%s\n",
821 estate2s (t->estate), cstate2s (t->cstate));
825 room = GMT_get_connections_buffer (t);
826 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
827 LOG (GNUNET_ERROR_TYPE_DEBUG, " tq head: %p\n", t->tq_head);
828 for (tqd = t->tq_head; NULL != tqd && room > 0; tqd = next)
830 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending queued data\n");
833 send_prebuilt_message ((struct GNUNET_MessageHeader *) &tqd[1],
835 NULL != tqd->tq ? tqd->tq->cont : NULL,
836 NULL != tqd->tq ? tqd->tq->cont_cls : NULL,
840 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_send_queued_data end\n", GMP_2s (t->peer));
845 * Sends key exchange message on a tunnel, choosing the best connection.
846 * Should not be called on loopback tunnels.
848 * @param t Tunnel on which this message is transmitted.
849 * @param message Message to send. Function modifies it.
852 send_kx (struct MeshTunnel3 *t,
853 const struct GNUNET_MessageHeader *message)
855 struct MeshConnection *c;
856 struct GNUNET_MESH_KX *msg;
857 size_t size = ntohs (message->size);
858 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
862 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
864 /* Avoid loopback. */
865 if (GMT_is_loopback (t))
867 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
872 /* Must have a connection. */
873 if (NULL == t->connection_head)
875 GNUNET_break (MESH_TUNNEL3_SEARCHING == t->cstate);
880 msg = (struct GNUNET_MESH_KX *) cbuf;
881 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
882 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
883 c = tunnel_get_connection (t);
886 GNUNET_break (GNUNET_YES == t->destroy || MESH_TUNNEL3_READY != t->cstate);
890 type = ntohs (message->type);
893 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
894 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
895 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
896 msg->reserved = htonl (0);
897 memcpy (&msg[1], message, size);
900 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
905 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
906 /* TODO save handle and cancel in case of a unneeded retransmission */
907 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
912 * Send the ephemeral key on a tunnel.
914 * @param t Tunnel on which to send the key.
917 send_ephemeral (struct MeshTunnel3 *t)
919 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
921 kx_msg.sender_status = htonl (t->estate);
922 send_kx (t, &kx_msg.header);
926 * Send a ping message on a tunnel.
928 * @param t Tunnel on which to send the ping.
931 send_ping (struct MeshTunnel3 *t)
933 struct GNUNET_MESH_KX_Ping msg;
935 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
936 msg.header.size = htons (sizeof (msg));
937 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
938 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
939 msg.target = *GMP_get_id (t->peer);
940 msg.nonce = t->kx_ctx->challenge;
942 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
943 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&msg.target));
944 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
945 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
946 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg.target));
948 send_kx (t, &msg.header);
953 * Send a pong message on a tunnel.
955 * @param t Tunnel on which to send the pong.
956 * @param challenge Value sent in the ping that we have to send back.
959 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
961 struct GNUNET_MESH_KX_Pong msg;
963 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
964 msg.header.size = htons (sizeof (msg));
965 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
966 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
967 msg.nonce = challenge;
968 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
969 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
970 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
972 send_kx (t, &msg.header);
977 * Initiate a rekey with the remote peer.
979 * @param cls Closure (tunnel).
980 * @param tc TaskContext.
983 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
985 struct MeshTunnel3 *t = cls;
987 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
989 LOG (GNUNET_ERROR_TYPE_DEBUG, "Re-key Tunnel %s\n", GMT_2s (t));
990 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
993 if (NULL == t->kx_ctx)
995 LOG (GNUNET_ERROR_TYPE_DEBUG, " new kx ctx\n");
996 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
997 t->kx_ctx->challenge =
998 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
999 t->kx_ctx->d_key_old = t->d_key;
1000 LOG (GNUNET_ERROR_TYPE_DEBUG, " new challenge for %s: %u\n",
1001 GMT_2s (t), t->kx_ctx->challenge);
1006 case MESH_TUNNEL3_KEY_UNINITIALIZED:
1007 t->estate = MESH_TUNNEL3_KEY_SENT;
1009 case MESH_TUNNEL3_KEY_SENT:
1011 case MESH_TUNNEL3_KEY_PING:
1012 case MESH_TUNNEL3_KEY_OK:
1014 t->estate = MESH_TUNNEL3_KEY_PING;
1017 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->estate);
1020 LOG (GNUNET_ERROR_TYPE_DEBUG, " next call in %s\n",
1021 GNUNET_STRINGS_relative_time_to_string (REKEY_WAIT, GNUNET_YES));
1022 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
1027 * Out ephemeral key has changed, create new session key on all tunnels.
1029 * @param cls Closure (size of the hashmap).
1030 * @param key Current public key.
1031 * @param value Value in the hash map (tunnel).
1033 * @return #GNUNET_YES, so we should continue to iterate,
1036 rekey_iterator (void *cls,
1037 const struct GNUNET_PeerIdentity *key,
1040 struct MeshTunnel3 *t = value;
1041 struct GNUNET_TIME_Relative delay;
1042 long n = (long) cls;
1045 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1048 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
1049 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
1050 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
1057 * Create a new ephemeral key and key message, schedule next rekeying.
1059 * @param cls Closure (unused).
1060 * @param tc TaskContext.
1063 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1065 struct GNUNET_TIME_Absolute time;
1068 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1070 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
1073 GNUNET_free_non_null (my_ephemeral_key);
1074 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
1076 time = GNUNET_TIME_absolute_get ();
1077 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
1078 time = GNUNET_TIME_absolute_add (time, rekey_period);
1079 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
1080 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
1081 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
1083 GNUNET_assert (GNUNET_OK ==
1084 GNUNET_CRYPTO_eddsa_sign (my_private_key,
1086 &kx_msg.signature));
1088 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
1089 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
1091 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
1096 * Called only on shutdown, destroy every tunnel.
1098 * @param cls Closure (unused).
1099 * @param key Current public key.
1100 * @param value Value in the hash map (tunnel).
1102 * @return #GNUNET_YES, so we should continue to iterate,
1105 destroy_iterator (void *cls,
1106 const struct GNUNET_PeerIdentity *key,
1109 struct MeshTunnel3 *t = value;
1117 * Demultiplex data per channel and call appropriate channel handler.
1119 * @param t Tunnel on which the data came.
1120 * @param msg Data message.
1121 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1122 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1123 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1124 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1127 handle_data (struct MeshTunnel3 *t,
1128 const struct GNUNET_MESH_Data *msg,
1131 struct MeshChannel *ch;
1135 size = ntohs (msg->header.size);
1137 sizeof (struct GNUNET_MESH_Data) +
1138 sizeof (struct GNUNET_MessageHeader))
1143 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
1144 GM_m2s (ntohs (msg[1].header.type)));
1147 ch = GMT_get_channel (t, ntohl (msg->chid));
1150 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
1152 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1157 GMCH_handle_data (ch, msg, fwd);
1162 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
1164 * @param t Tunnel on which the DATA ACK came.
1165 * @param msg DATA ACK message.
1166 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1167 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1168 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1169 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1172 handle_data_ack (struct MeshTunnel3 *t,
1173 const struct GNUNET_MESH_DataACK *msg,
1176 struct MeshChannel *ch;
1180 size = ntohs (msg->header.size);
1181 if (size != sizeof (struct GNUNET_MESH_DataACK))
1188 ch = GMT_get_channel (t, ntohl (msg->chid));
1191 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
1193 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1198 GMCH_handle_data_ack (ch, msg, fwd);
1203 * Handle channel create.
1205 * @param t Tunnel on which the data came.
1206 * @param msg Data message.
1209 handle_ch_create (struct MeshTunnel3 *t,
1210 const struct GNUNET_MESH_ChannelCreate *msg)
1212 struct MeshChannel *ch;
1216 size = ntohs (msg->header.size);
1217 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
1224 ch = GMT_get_channel (t, ntohl (msg->chid));
1225 if (NULL != ch && ! GMT_is_loopback (t))
1227 /* Probably a retransmission, safe to ignore */
1228 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
1232 ch = GMCH_handle_create (t, msg);
1235 GMT_add_channel (t, ch);
1241 * Handle channel NACK: check correctness and call channel handler for NACKs.
1243 * @param t Tunnel on which the NACK came.
1244 * @param msg NACK message.
1247 handle_ch_nack (struct MeshTunnel3 *t,
1248 const struct GNUNET_MESH_ChannelManage *msg)
1250 struct MeshChannel *ch;
1254 size = ntohs (msg->header.size);
1255 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1262 ch = GMT_get_channel (t, ntohl (msg->chid));
1265 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
1267 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1272 GMCH_handle_nack (ch);
1277 * Handle a CHANNEL ACK (SYNACK/ACK).
1279 * @param t Tunnel on which the CHANNEL ACK came.
1280 * @param msg CHANNEL ACK message.
1281 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1282 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1283 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1284 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1287 handle_ch_ack (struct MeshTunnel3 *t,
1288 const struct GNUNET_MESH_ChannelManage *msg,
1291 struct MeshChannel *ch;
1295 size = ntohs (msg->header.size);
1296 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1303 ch = GMT_get_channel (t, ntohl (msg->chid));
1306 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1308 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1313 GMCH_handle_ack (ch, msg, fwd);
1319 * Handle a channel destruction message.
1321 * @param t Tunnel on which the message came.
1322 * @param msg Channel destroy message.
1323 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1324 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1325 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1326 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1329 handle_ch_destroy (struct MeshTunnel3 *t,
1330 const struct GNUNET_MESH_ChannelManage *msg,
1333 struct MeshChannel *ch;
1337 size = ntohs (msg->header.size);
1338 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1345 ch = GMT_get_channel (t, ntohl (msg->chid));
1348 /* Probably a retransmission, safe to ignore */
1352 GMCH_handle_destroy (ch, msg, fwd);
1357 * The peer's ephemeral key has changed: update the symmetrical keys.
1359 * @param t Tunnel this message came on.
1360 * @param msg Key eXchange message.
1363 handle_ephemeral (struct MeshTunnel3 *t,
1364 const struct GNUNET_MESH_KX_Ephemeral *msg)
1366 struct GNUNET_HashCode km;
1367 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1369 if (GNUNET_OK != check_ephemeral (t, msg))
1371 GNUNET_break_op (0);
1374 derive_key_material (&km, &msg->ephemeral_key);
1375 LOG (GNUNET_ERROR_TYPE_DEBUG, " km is %s\n", GNUNET_h2s (&km));
1376 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1377 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1378 if (MESH_TUNNEL3_KEY_SENT == t->estate)
1380 LOG (GNUNET_ERROR_TYPE_DEBUG, " our key was sent, send ping\n");
1382 t->estate = MESH_TUNNEL3_KEY_PING;
1388 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1389 * Answer with by retransmitting the challenge with the "opposite" key.
1391 * @param t Tunnel this message came on.
1392 * @param msg Key eXchange Ping message.
1395 handle_ping (struct MeshTunnel3 *t,
1396 const struct GNUNET_MESH_KX_Ping *msg)
1398 struct GNUNET_MESH_KX_Ping res;
1400 if (ntohs (msg->header.size) != sizeof (res))
1402 GNUNET_break_op (0);
1406 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1407 t_decrypt (t, &res.target, &msg->target, ping_encryption_size (), msg->iv);
1408 if (0 != memcmp (&my_full_id, &res.target, sizeof (my_full_id)))
1410 GNUNET_break_op (0);
1411 LOG (GNUNET_ERROR_TYPE_DEBUG, " e got %u\n", msg->nonce);
1412 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg->target));
1413 LOG (GNUNET_ERROR_TYPE_DEBUG, " got %u\n", res.nonce);
1414 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&res.target));
1418 send_pong (t, res.nonce);
1423 * Peer has answer to our challenge.
1424 * If answer is successful, consider the key exchange finished and clean
1425 * up all related state.
1427 * @param t Tunnel this message came on.
1428 * @param msg Key eXchange Pong message.
1431 handle_pong (struct MeshTunnel3 *t,
1432 const struct GNUNET_MESH_KX_Pong *msg)
1436 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1437 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1439 GNUNET_STATISTICS_update (stats, "# duplicate PONG messages", 1, GNUNET_NO);
1442 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1444 if (challenge != t->kx_ctx->challenge)
1446 LOG (GNUNET_ERROR_TYPE_DEBUG,
1447 "Wrong PONG challenge: %u (e: %u). Expected: %u.\n",
1448 challenge, msg->nonce, t->kx_ctx->challenge);
1449 GNUNET_break_op (0);
1452 GNUNET_SCHEDULER_cancel (t->rekey_task);
1453 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1454 GNUNET_free (t->kx_ctx);
1456 GMT_change_estate (t, MESH_TUNNEL3_KEY_OK);
1461 * Demultiplex by message type and call appropriate handler for a message
1462 * towards a channel of a local tunnel.
1464 * @param t Tunnel this message came on.
1465 * @param msgh Message header.
1466 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1467 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1468 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1469 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1472 handle_decrypted (struct MeshTunnel3 *t,
1473 const struct GNUNET_MessageHeader *msgh,
1478 type = ntohs (msgh->type);
1479 LOG (GNUNET_ERROR_TYPE_DEBUG,
1480 "Got a %s message!\n",
1485 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1486 /* Don't send hop ACK, wait for client to ACK */
1487 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1490 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1491 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1494 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1495 handle_ch_create (t,
1496 (struct GNUNET_MESH_ChannelCreate *) msgh);
1499 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1501 (struct GNUNET_MESH_ChannelManage *) msgh);
1504 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1506 (struct GNUNET_MESH_ChannelManage *) msgh,
1510 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1511 handle_ch_destroy (t,
1512 (struct GNUNET_MESH_ChannelManage *) msgh,
1517 GNUNET_break_op (0);
1518 LOG (GNUNET_ERROR_TYPE_DEBUG,
1519 "end-to-end message not known (%u)\n",
1520 ntohs (msgh->type));
1524 /******************************************************************************/
1525 /******************************** API ***********************************/
1526 /******************************************************************************/
1529 * Decrypt and demultiplex by message type. Call appropriate handler
1530 * for every message.
1532 * @param t Tunnel this message came on.
1533 * @param msg Encrypted message.
1536 GMT_handle_encrypted (struct MeshTunnel3 *t,
1537 const struct GNUNET_MESH_Encrypted *msg)
1539 size_t size = ntohs (msg->header.size);
1540 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1541 size_t decrypted_size;
1542 char cbuf [payload_size];
1543 struct GNUNET_MessageHeader *msgh;
1546 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1548 while (off < decrypted_size)
1550 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1551 handle_decrypted (t, msgh, GNUNET_SYSERR);
1552 off += ntohs (msgh->size);
1558 * Demultiplex an encapsulated KX message by message type.
1560 * @param t Tunnel on which the message came.
1561 * @param message Payload of KX message.
1564 GMT_handle_kx (struct MeshTunnel3 *t,
1565 const struct GNUNET_MessageHeader *message)
1569 type = ntohs (message->type);
1570 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1573 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1574 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1577 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1578 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1581 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1582 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1586 GNUNET_break_op (0);
1587 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1593 * Initialize the tunnel subsystem.
1595 * @param c Configuration handle.
1596 * @param key ECC private key, to derive all other keys and do crypto.
1599 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1600 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1602 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1604 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1607 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1608 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1612 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1615 rekey_period = GNUNET_TIME_UNIT_DAYS;
1618 my_private_key = key;
1619 kx_msg.header.size = htons (sizeof (kx_msg));
1620 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1621 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1622 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1623 kx_msg.origin_identity = my_full_id;
1624 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1626 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1631 * Shut down the tunnel subsystem.
1636 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1638 GNUNET_SCHEDULER_cancel (rekey_task);
1639 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1641 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &destroy_iterator, NULL);
1642 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1649 * @param destination Peer this tunnel is towards.
1651 struct MeshTunnel3 *
1652 GMT_new (struct MeshPeer *destination)
1654 struct MeshTunnel3 *t;
1656 t = GNUNET_new (struct MeshTunnel3);
1658 t->peer = destination;
1661 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1662 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1673 * Change the tunnel's connection state.
1675 * @param t Tunnel whose connection state to change.
1676 * @param cstate New connection state.
1679 GMT_change_cstate (struct MeshTunnel3* t, enum MeshTunnel3CState cstate)
1683 LOG (GNUNET_ERROR_TYPE_DEBUG,
1684 "Tunnel %s cstate was %s\n",
1685 GMP_2s (t->peer), cstate2s (t->cstate));
1686 LOG (GNUNET_ERROR_TYPE_DEBUG,
1687 "Tunnel %s cstate is now %s\n",
1688 GMP_2s (t->peer), cstate2s (cstate));
1689 if (myid != GMP_get_short_id (t->peer) &&
1690 MESH_TUNNEL3_READY != t->cstate &&
1691 MESH_TUNNEL3_READY == cstate)
1694 if (MESH_TUNNEL3_KEY_OK == t->estate)
1696 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered send queued data\n");
1697 send_queued_data (t);
1699 else if (MESH_TUNNEL3_KEY_UNINITIALIZED == t->estate)
1701 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1702 rekey_tunnel (t, NULL);
1707 if (MESH_TUNNEL3_READY == cstate && 3 <= GMT_count_connections (t))
1709 GMP_stop_search (t->peer);
1714 * Change the tunnel encryption state.
1716 * @param t Tunnel whose encryption state to change.
1717 * @param state New encryption state.
1720 GMT_change_estate (struct MeshTunnel3* t, enum MeshTunnel3EState state)
1724 LOG (GNUNET_ERROR_TYPE_DEBUG,
1725 "Tunnel %s estate was %s\n",
1726 GMP_2s (t->peer), estate2s (t->estate));
1727 LOG (GNUNET_ERROR_TYPE_DEBUG,
1728 "Tunnel %s estate is now %s\n",
1729 GMP_2s (t->peer), estate2s (state));
1730 if (myid != GMP_get_short_id (t->peer) &&
1731 MESH_TUNNEL3_KEY_OK != t->estate && MESH_TUNNEL3_KEY_OK == state)
1734 send_queued_data (t);
1742 * Add a connection to a tunnel.
1745 * @param c Connection.
1748 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1750 struct MeshTConnection *aux;
1752 GNUNET_assert (NULL != c);
1754 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1758 aux = GNUNET_new (struct MeshTConnection);
1760 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1765 * Mark a path as no longer valid for this tunnel: has been tried and failed.
1767 * @param t Tunnel to update.
1768 * @param path Invalid path to remove. Is destroyed after removal.
1771 GMT_remove_path (struct MeshTunnel3 *t, struct MeshPeerPath *path)
1773 GMP_remove_path (t->peer, path);
1778 * Remove a connection from a tunnel.
1781 * @param c Connection.
1784 GMT_remove_connection (struct MeshTunnel3 *t,
1785 struct MeshConnection *c)
1787 struct MeshTConnection *aux;
1788 struct MeshTConnection *next;
1790 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing connection %s from tunnel %s\n",
1791 GMC_2s (c), GMT_2s (t));
1792 for (aux = t->connection_head; aux != NULL; aux = next)
1797 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1802 /* Start new connections if needed */
1803 if (NULL == t->connection_head
1804 && GNUNET_NO == t->destroy
1805 && GNUNET_NO == shutting_down)
1807 LOG (GNUNET_ERROR_TYPE_DEBUG, " no more connections, getting new ones\n");
1808 GMP_connect (t->peer);
1809 t->cstate = MESH_TUNNEL3_SEARCHING;
1813 /* If not marked as ready, no change is needed */
1814 if (MESH_TUNNEL3_READY != t->cstate)
1817 /* Check if any connection is ready to maintaing cstate */
1818 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1819 if (MESH_CONNECTION_READY == GMC_get_state (aux->c))
1822 t->cstate = MESH_TUNNEL3_WAITING;
1827 * Add a channel to a tunnel.
1830 * @param ch Channel.
1833 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1835 struct MeshTChannel *aux;
1837 GNUNET_assert (NULL != ch);
1839 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1841 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1843 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1848 aux = GNUNET_new (struct MeshTChannel);
1850 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1851 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1853 if (GNUNET_YES == t->destroy)
1855 t->destroy = GNUNET_NO;
1856 LOG (GNUNET_ERROR_TYPE_DEBUG, " undo destroy!\n");
1862 * Remove a channel from a tunnel.
1865 * @param ch Channel.
1868 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1870 struct MeshTChannel *aux;
1872 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1873 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1877 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1878 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1887 * Search for a channel by global ID.
1889 * @param t Tunnel containing the channel.
1890 * @param chid Public channel number.
1892 * @return channel handler, NULL if doesn't exist
1894 struct MeshChannel *
1895 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1897 struct MeshTChannel *iter;
1902 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1904 if (GMCH_get_id (iter->ch) == chid)
1908 return NULL == iter ? NULL : iter->ch;
1913 * Tunnel is empty: destroy it.
1915 * Notifies all connections about the destruction.
1917 * @param t Tunnel to destroy.
1920 GMT_destroy_empty (struct MeshTunnel3 *t)
1922 struct MeshTConnection *iter;
1924 LOG (GNUNET_ERROR_TYPE_DEBUG, "Tunnel %s empty: destroying scheduled\n",
1926 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1928 GMC_send_destroy (iter->c);
1931 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1933 t->estate = MESH_TUNNEL3_KEY_UNINITIALIZED;
1934 GNUNET_SCHEDULER_cancel (t->rekey_task);
1935 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1936 GNUNET_free (t->kx_ctx);
1939 t->cstate = MESH_TUNNEL3_NEW;
1940 t->destroy = GNUNET_YES;
1945 * Destroy tunnel if empty (no more channels).
1947 * @param t Tunnel to destroy if empty.
1950 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1952 if (1 < GMT_count_channels (t))
1955 GMT_destroy_empty (t);
1960 * Destroy the tunnel.
1962 * This function does not generate any warning traffic to clients or peers.
1965 * Cancel messages belonging to this tunnel queued to neighbors.
1966 * Free any allocated resources linked to the tunnel.
1968 * @param t The tunnel to destroy.
1971 GMT_destroy (struct MeshTunnel3 *t)
1973 struct MeshTConnection *iter_c;
1974 struct MeshTConnection *next_c;
1975 struct MeshTChannel *iter_ch;
1976 struct MeshTChannel *next_ch;
1983 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
1985 GNUNET_break (GNUNET_YES ==
1986 GNUNET_CONTAINER_multipeermap_remove (tunnels,
1987 GMP_get_id (t->peer), t));
1989 for (iter_c = t->connection_head; NULL != iter_c; iter_c = next_c)
1991 next_c = iter_c->next;
1992 GMC_destroy (iter_c->c);
1994 for (iter_ch = t->channel_head; NULL != iter_ch; iter_ch = next_ch)
1996 next_ch = iter_ch->next;
1997 GMCH_destroy (iter_ch->ch);
1998 /* Should only happen on shutdown, but it's ok. */
2001 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
2002 GMP_set_tunnel (t->peer, NULL);
2004 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
2005 GNUNET_SCHEDULER_cancel (t->rekey_task);
2012 * @brief Use the given path for the tunnel.
2013 * Update the next and prev hops (and RCs).
2014 * (Re)start the path refresh in case the tunnel is locally owned.
2016 * @param t Tunnel to update.
2017 * @param p Path to use.
2019 * @return Connection created.
2021 struct MeshConnection *
2022 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
2024 struct MeshConnection *c;
2025 struct GNUNET_HashCode cid;
2026 unsigned int own_pos;
2028 if (NULL == t || NULL == p)
2034 for (own_pos = 0; own_pos < p->length; own_pos++)
2036 if (p->peers[own_pos] == myid)
2039 if (own_pos > p->length - 1)
2041 GNUNET_break_op (0);
2045 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
2046 c = GMC_new (&cid, t, p, own_pos);
2049 /* Path was flawed */
2052 GMT_add_connection (t, c);
2058 * Count established (ready) connections of a tunnel.
2060 * @param t Tunnel on which to count.
2062 * @return Number of connections.
2065 GMT_count_connections (struct MeshTunnel3 *t)
2067 struct MeshTConnection *iter;
2070 for (count = 0, iter = t->connection_head;
2072 iter = iter->next, count++);
2078 * Count channels of a tunnel.
2080 * @param t Tunnel on which to count.
2082 * @return Number of channels.
2085 GMT_count_channels (struct MeshTunnel3 *t)
2087 struct MeshTChannel *iter;
2090 for (count = 0, iter = t->channel_head;
2092 iter = iter->next, count++) /* skip */;
2099 * Get the connectivity state of a tunnel.
2103 * @return Tunnel's connectivity state.
2105 enum MeshTunnel3CState
2106 GMT_get_cstate (struct MeshTunnel3 *t)
2111 return (enum MeshTunnel3CState) -1;
2118 * Get the maximum buffer space for a tunnel towards a local client.
2122 * @return Biggest buffer space offered by any channel in the tunnel.
2125 GMT_get_channels_buffer (struct MeshTunnel3 *t)
2127 struct MeshTChannel *iter;
2128 unsigned int buffer;
2129 unsigned int ch_buf;
2131 if (NULL == t->channel_head)
2133 /* Probably getting buffer for a channel create/handshake. */
2138 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2140 ch_buf = get_channel_buffer (iter);
2141 if (ch_buf > buffer)
2149 * Get the total buffer space for a tunnel for P2P traffic.
2153 * @return Buffer space offered by all connections in the tunnel.
2156 GMT_get_connections_buffer (struct MeshTunnel3 *t)
2158 struct MeshTConnection *iter;
2159 unsigned int buffer;
2162 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2164 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
2168 buffer += get_connection_buffer (iter);
2176 * Get the tunnel's destination.
2180 * @return ID of the destination peer.
2182 const struct GNUNET_PeerIdentity *
2183 GMT_get_destination (struct MeshTunnel3 *t)
2185 return GMP_get_id (t->peer);
2190 * Get the tunnel's next free global channel ID.
2194 * @return GID of a channel free to use.
2197 GMT_get_next_chid (struct MeshTunnel3 *t)
2199 MESH_ChannelNumber chid;
2200 MESH_ChannelNumber mask;
2203 /* Set bit 30 depending on the ID relationship. Bit 31 is always 0 for GID.
2204 * If our ID is bigger or loopback tunnel, start at 0, bit 30 = 0
2205 * If peer's ID is bigger, start at 0x4... bit 30 = 1
2207 result = GNUNET_CRYPTO_cmp_peer_identity (&my_full_id, GMP_get_id (t->peer));
2213 while (NULL != GMT_get_channel (t, t->next_chid))
2215 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
2216 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2217 t->next_chid |= mask;
2219 chid = t->next_chid;
2220 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2221 t->next_chid |= mask;
2228 * Send ACK on one or more channels due to buffer in connections.
2230 * @param t Channel which has some free buffer space.
2233 GMT_unchoke_channels (struct MeshTunnel3 *t)
2235 struct MeshTChannel *iter;
2236 unsigned int buffer;
2237 unsigned int channels = GMT_count_channels (t);
2238 unsigned int choked_n;
2239 struct MeshChannel *choked[channels];
2241 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
2242 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
2243 if (NULL != t->channel_head)
2244 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
2246 /* Get buffer space */
2247 buffer = GMT_get_connections_buffer (t);
2253 /* Count and remember choked channels */
2255 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2257 if (GNUNET_NO == get_channel_allowed (iter))
2259 choked[choked_n++] = iter->ch;
2263 /* Unchoke random channels */
2264 while (0 < buffer && 0 < choked_n)
2266 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2268 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
2271 choked[r] = choked[choked_n];
2277 * Send ACK on one or more connections due to buffer space to the client.
2279 * Iterates all connections of the tunnel and sends ACKs appropriately.
2284 GMT_send_connection_acks (struct MeshTunnel3 *t)
2286 struct MeshTConnection *iter;
2289 uint32_t allow_per_connection;
2291 unsigned int buffer;
2293 LOG (GNUNET_ERROR_TYPE_DEBUG,
2294 "Tunnel send connection ACKs on %s\n",
2303 buffer = GMT_get_channels_buffer (t);
2305 /* Count connections, how many messages are already allowed */
2306 cs = GMT_count_connections (t);
2307 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
2309 allowed += get_connection_allowed (iter);
2312 /* Make sure there is no overflow */
2313 if (allowed > buffer)
2318 /* Authorize connections to send more data */
2319 to_allow = buffer; /* - allowed; */
2321 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
2323 allow_per_connection = to_allow/cs;
2324 to_allow -= allow_per_connection;
2326 if (get_connection_allowed (iter) > 64 / 3)
2330 GMC_allow (iter->c, buffer, GMC_is_origin (iter->c, GNUNET_YES));
2333 GNUNET_break (to_allow == 0);
2338 * Cancel a previously sent message while it's in the queue.
2340 * ONLY can be called before the continuation given to the send function
2341 * is called. Once the continuation is called, the message is no longer in the
2344 * @param q Handle to the queue.
2347 GMT_cancel (struct MeshTunnel3Queue *q)
2352 /* message_sent() will be called and free q */
2354 else if (NULL != q->tqd)
2356 unqueue_data (q->tqd);
2366 * Sends an already built message on a tunnel, encrypting it and
2367 * choosing the best connection.
2369 * @param message Message to send. Function modifies it.
2370 * @param t Tunnel on which this message is transmitted.
2371 * @param force Force the tunnel to take the message (buffer overfill).
2372 * @param cont Continuation to call once message is really sent.
2373 * @param cont_cls Closure for @c cont.
2375 * @return Handle to cancel message. NULL if @c cont is NULL.
2377 struct MeshTunnel3Queue *
2378 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2379 struct MeshTunnel3 *t, int force,
2380 GMT_sent cont, void *cont_cls)
2382 return send_prebuilt_message (message, t, force, cont, cont_cls, NULL);
2387 * Is the tunnel directed towards the local peer?
2391 * @return #GNUNET_YES if it is loopback.
2394 GMT_is_loopback (const struct MeshTunnel3 *t)
2396 return (myid == GMP_get_short_id (t->peer));
2401 * Is the tunnel this path already?
2406 * @return #GNUNET_YES a connection uses this path.
2409 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2411 struct MeshTConnection *iter;
2413 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2414 if (GMC_get_path (iter->c) == p)
2422 * Get a cost of a path for a tunnel considering existing connections.
2425 * @param path Candidate path.
2427 * @return Cost of the path (path length + number of overlapping nodes)
2430 GMT_get_path_cost (const struct MeshTunnel3 *t,
2431 const struct MeshPeerPath *path)
2433 struct MeshTConnection *iter;
2434 const struct MeshPeerPath *aux;
2435 unsigned int overlap;
2443 GNUNET_assert (NULL != t);
2445 for (i = 0; i < path->length; i++)
2447 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2449 aux = GMC_get_path (iter->c);
2453 for (j = 0; j < aux->length; j++)
2455 if (path->peers[i] == aux->peers[j])
2463 return (path->length + overlap) * (path->score * -1);
2468 * Get the static string for the peer this tunnel is directed.
2472 * @return Static string the destination peer's ID.
2475 GMT_2s (const struct MeshTunnel3 *t)
2480 return GMP_2s (t->peer);
2485 * Log all possible info about the tunnel state.
2487 * @param t Tunnel to debug.
2490 GMT_debug (const struct MeshTunnel3 *t)
2492 struct MeshTChannel *iterch;
2493 struct MeshTConnection *iterc;
2495 LOG (GNUNET_ERROR_TYPE_DEBUG, "DEBUG %s\n", GMT_2s (t));
2496 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate %s, estate %s\n",
2497 cstate2s (t->cstate), estate2s (t->estate));
2499 LOG (GNUNET_ERROR_TYPE_DEBUG, " channels:\n");
2500 for (iterch = t->channel_head; NULL != iterch; iterch = iterch->next)
2502 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %s\n", GMCH_2s (iterch->ch));
2505 LOG (GNUNET_ERROR_TYPE_DEBUG, " connections:\n");
2506 for (iterc = t->connection_head; NULL != iterc; iterc = iterc->next)
2508 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %s\n", GMC_2s (iterc->c));
2511 LOG (GNUNET_ERROR_TYPE_DEBUG, "DEBUG END\n");