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;
528 struct GNUNET_CRYPTO_SymmetricSessionKey *key;
530 if (t->estate == MESH_TUNNEL3_KEY_OK || t->estate == MESH_TUNNEL3_KEY_PING)
534 else if (NULL != t->kx_ctx)
536 key = &t->kx_ctx->d_key_old;
540 GNUNET_STATISTICS_update (stats, "# non decryptable data", 1, GNUNET_NO);
541 LOG (GNUNET_ERROR_TYPE_DEBUG,
542 "WARNING got data on %s without a valid key\n",
547 GNUNET_CRYPTO_symmetric_derive_iv (&siv, key, &iv, sizeof (uint32_t), NULL);
548 return GNUNET_CRYPTO_symmetric_decrypt (src, size, key, &siv, dst);
553 * Create key material by doing ECDH on the local and remote ephemeral keys.
555 * @param key_material Where to store the key material.
556 * @param ephemeral_key Peer's public ephemeral key.
559 derive_key_material (struct GNUNET_HashCode *key_material,
560 const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key)
563 GNUNET_CRYPTO_ecc_ecdh (my_ephemeral_key,
572 * Create a symmetic key from the identities of both ends and the key material
575 * @param key Destination for the generated key.
576 * @param sender ID of the peer that will encrypt with @c key.
577 * @param receiver ID of the peer that will decrypt with @c key.
578 * @param key_material Hash created with ECDH with the ephemeral keys.
581 derive_symmertic (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
582 const struct GNUNET_PeerIdentity *sender,
583 const struct GNUNET_PeerIdentity *receiver,
584 const struct GNUNET_HashCode *key_material)
586 const char salt[] = "MESH kx salt";
588 GNUNET_CRYPTO_kdf (key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
590 key_material, sizeof (struct GNUNET_HashCode),
591 sender, sizeof (struct GNUNET_PeerIdentity),
592 receiver, sizeof (struct GNUNET_PeerIdentity),
597 * Pick a connection on which send the next data message.
599 * @param t Tunnel on which to send the message.
601 * @return The connection on which to send the next message.
603 static struct MeshConnection *
604 tunnel_get_connection (struct MeshTunnel3 *t)
606 struct MeshTConnection *iter;
607 struct MeshConnection *best;
609 unsigned int lowest_q;
611 LOG (GNUNET_ERROR_TYPE_DEBUG, "tunnel_get_connection %s\n", GMP_2s (t->peer));
614 for (iter = t->connection_head; NULL != iter; iter = iter->next)
616 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s: %u\n",
617 GMC_2s (iter->c), GMC_get_state (iter->c));
618 if (MESH_CONNECTION_READY == GMC_get_state (iter->c))
620 qn = GMC_get_qn (iter->c, GMC_is_origin (iter->c, GNUNET_YES));
621 LOG (GNUNET_ERROR_TYPE_DEBUG, " q_n %u, \n", qn);
629 LOG (GNUNET_ERROR_TYPE_DEBUG, " selected: connection %s\n", GMC_2s (best));
635 * Callback called when a queued message is sent.
637 * Calculates the average time and connection packet tracking.
639 * @param cls Closure (TunnelQueue handle).
640 * @param c Connection this message was on.
641 * @param q Connection queue handle (unused).
642 * @param type Type of message sent.
643 * @param fwd Was this a FWD going message?
644 * @param size Size of the message.
647 message_sent (void *cls,
648 struct MeshConnection *c,
649 struct MeshConnectionQueue *q,
650 uint16_t type, int fwd, size_t size)
652 struct MeshTunnel3Queue *qt = cls;
654 GNUNET_assert (NULL != qt->cont);
655 qt->cont (qt->cont_cls, GMC_get_tunnel (c), qt, type, size);
661 * Delete a queued message: either was sent or the channel was destroyed
662 * before the tunnel's key exchange had a chance to finish.
664 * @param tqd Delayed queue handle.
667 unqueue_data (struct MeshTunnelDelayed *tqd)
669 GNUNET_CONTAINER_DLL_remove (tqd->t->tq_head, tqd->t->tq_tail, tqd);
675 * Cache a message to be sent once tunnel is online.
677 * @param t Tunnel to hold the message.
678 * @param msg Message itself (copy will be made).
680 static struct MeshTunnelDelayed *
681 queue_data (struct MeshTunnel3 *t, const struct GNUNET_MessageHeader *msg)
683 struct MeshTunnelDelayed *tqd;
684 uint16_t size = ntohs (msg->size);
686 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue data on Tunnel %s\n", GMT_2s (t));
688 if (GNUNET_YES == is_ready (t))
694 tqd = GNUNET_malloc (sizeof (struct MeshTunnelDelayed) + size);
697 memcpy (&tqd[1], msg, size);
698 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tqd);
705 * Sends an already built message on a tunnel, encrypting it and
706 * choosing the best connection.
708 * @param message Message to send. Function modifies it.
709 * @param t Tunnel on which this message is transmitted.
710 * @param force Force the tunnel to take the message (buffer overfill).
711 * @param cont Continuation to call once message is really sent.
712 * @param cont_cls Closure for @c cont.
713 * @param existing_q In case this a transmission of previously queued data,
714 * this should be TunnelQueue given to the client.
717 * @return Handle to cancel message. NULL if @c cont is NULL.
719 static struct MeshTunnel3Queue *
720 send_prebuilt_message (const struct GNUNET_MessageHeader *message,
721 struct MeshTunnel3 *t, int force,
722 GMT_sent cont, void *cont_cls,
723 struct MeshTunnel3Queue *existing_q)
725 struct MeshTunnel3Queue *tq;
726 struct MeshConnection *c;
727 struct GNUNET_MESH_Encrypted *msg;
728 size_t size = ntohs (message->size);
729 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
734 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
736 if (GNUNET_NO == is_ready (t))
738 struct MeshTunnelDelayed *tqd;
739 /* A non null existing_q indicates sending of queued data.
740 * Should only happen after tunnel becomes ready.
742 GNUNET_assert (NULL == existing_q);
743 tqd = queue_data (t, message);
746 tq = GNUNET_new (struct MeshTunnel3Queue);
750 tq->cont_cls = cont_cls;
754 GNUNET_assert (GNUNET_NO == GMT_is_loopback (t));
756 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
757 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
758 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
760 GNUNET_assert (t_encrypt (t, &msg[1], message, size, iv) == size);
761 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + size);
762 c = tunnel_get_connection (t);
765 if (GNUNET_YES == t->destroy || MESH_TUNNEL3_SEARCHING != t->cstate)
772 type = ntohs (message->type);
775 case GNUNET_MESSAGE_TYPE_MESH_DATA:
776 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
777 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
778 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
779 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
780 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
781 msg->cid = *GMC_get_id (c);
782 msg->ttl = htonl (default_ttl);
785 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
790 fwd = GMC_is_origin (c, GNUNET_YES);
794 (void) GMC_send_prebuilt_message (&msg->header, c, fwd, force, NULL, NULL);
797 if (NULL == existing_q)
799 tq = GNUNET_new (struct MeshTunnel3Queue); /* FIXME valgrind: leak*/
806 tq->cq = GMC_send_prebuilt_message (&msg->header, c, fwd, force,
809 tq->cont_cls = cont_cls;
816 * Send all cached messages that we can, tunnel is online.
818 * @param t Tunnel that holds the messages. Cannot be loopback.
821 send_queued_data (struct MeshTunnel3 *t)
823 struct MeshTunnelDelayed *tqd;
824 struct MeshTunnelDelayed *next;
827 LOG (GNUNET_ERROR_TYPE_DEBUG,
828 "GMT_send_queued_data on tunnel %s\n",
831 if (GMT_is_loopback (t))
837 if (GNUNET_NO == is_ready (t))
839 LOG (GNUNET_ERROR_TYPE_DEBUG, " not ready yet: %s/%s\n",
840 estate2s (t->estate), cstate2s (t->cstate));
844 room = GMT_get_connections_buffer (t);
845 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
846 LOG (GNUNET_ERROR_TYPE_DEBUG, " tq head: %p\n", t->tq_head);
847 for (tqd = t->tq_head; NULL != tqd && room > 0; tqd = next)
849 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending queued data\n");
852 send_prebuilt_message ((struct GNUNET_MessageHeader *) &tqd[1],
854 NULL != tqd->tq ? tqd->tq->cont : NULL,
855 NULL != tqd->tq ? tqd->tq->cont_cls : NULL,
859 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_send_queued_data end\n", GMP_2s (t->peer));
864 * Sends key exchange message on a tunnel, choosing the best connection.
865 * Should not be called on loopback tunnels.
867 * @param t Tunnel on which this message is transmitted.
868 * @param message Message to send. Function modifies it.
871 send_kx (struct MeshTunnel3 *t,
872 const struct GNUNET_MessageHeader *message)
874 struct MeshConnection *c;
875 struct GNUNET_MESH_KX *msg;
876 size_t size = ntohs (message->size);
877 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
881 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
883 /* Avoid loopback. */
884 if (GMT_is_loopback (t))
886 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
891 /* Must have a connection. */
892 if (NULL == t->connection_head)
894 GNUNET_break (MESH_TUNNEL3_SEARCHING == t->cstate);
899 msg = (struct GNUNET_MESH_KX *) cbuf;
900 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
901 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
902 c = tunnel_get_connection (t);
905 GNUNET_break (GNUNET_YES == t->destroy || MESH_TUNNEL3_READY != t->cstate);
909 type = ntohs (message->type);
912 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
913 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
914 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
915 msg->reserved = htonl (0);
916 memcpy (&msg[1], message, size);
919 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
924 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
925 /* TODO save handle and cancel in case of a unneeded retransmission */
926 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
931 * Send the ephemeral key on a tunnel.
933 * @param t Tunnel on which to send the key.
936 send_ephemeral (struct MeshTunnel3 *t)
938 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
940 kx_msg.sender_status = htonl (t->estate);
941 send_kx (t, &kx_msg.header);
945 * Send a ping message on a tunnel.
947 * @param t Tunnel on which to send the ping.
950 send_ping (struct MeshTunnel3 *t)
952 struct GNUNET_MESH_KX_Ping msg;
954 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
955 msg.header.size = htons (sizeof (msg));
956 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
957 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
958 msg.target = *GMP_get_id (t->peer);
959 msg.nonce = t->kx_ctx->challenge;
961 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
962 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&msg.target));
963 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
964 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
965 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg.target));
967 send_kx (t, &msg.header);
972 * Send a pong message on a tunnel.
974 * @param t Tunnel on which to send the pong.
975 * @param challenge Value sent in the ping that we have to send back.
978 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
980 struct GNUNET_MESH_KX_Pong msg;
982 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
983 msg.header.size = htons (sizeof (msg));
984 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
985 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
986 msg.nonce = challenge;
987 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
988 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
989 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
991 send_kx (t, &msg.header);
996 * Initiate a rekey with the remote peer.
998 * @param cls Closure (tunnel).
999 * @param tc TaskContext.
1002 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1004 struct MeshTunnel3 *t = cls;
1006 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1008 LOG (GNUNET_ERROR_TYPE_DEBUG, "Re-key Tunnel %s\n", GMT_2s (t));
1009 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
1012 if (NULL == t->kx_ctx)
1014 LOG (GNUNET_ERROR_TYPE_DEBUG, " new kx ctx\n");
1015 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
1016 t->kx_ctx->challenge =
1017 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
1018 t->kx_ctx->d_key_old = t->d_key;
1019 LOG (GNUNET_ERROR_TYPE_DEBUG, " new challenge for %s: %u\n",
1020 GMT_2s (t), t->kx_ctx->challenge);
1025 case MESH_TUNNEL3_KEY_UNINITIALIZED:
1026 t->estate = MESH_TUNNEL3_KEY_SENT;
1028 case MESH_TUNNEL3_KEY_SENT:
1030 case MESH_TUNNEL3_KEY_PING:
1031 case MESH_TUNNEL3_KEY_OK:
1033 t->estate = MESH_TUNNEL3_KEY_PING;
1036 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->estate);
1039 LOG (GNUNET_ERROR_TYPE_DEBUG, " next call in %s\n",
1040 GNUNET_STRINGS_relative_time_to_string (REKEY_WAIT, GNUNET_YES));
1041 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
1046 * Out ephemeral key has changed, create new session key on all tunnels.
1048 * @param cls Closure (size of the hashmap).
1049 * @param key Current public key.
1050 * @param value Value in the hash map (tunnel).
1052 * @return #GNUNET_YES, so we should continue to iterate,
1055 rekey_iterator (void *cls,
1056 const struct GNUNET_PeerIdentity *key,
1059 struct MeshTunnel3 *t = value;
1060 struct GNUNET_TIME_Relative delay;
1061 long n = (long) cls;
1064 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1067 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
1068 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
1069 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
1076 * Create a new ephemeral key and key message, schedule next rekeying.
1078 * @param cls Closure (unused).
1079 * @param tc TaskContext.
1082 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1084 struct GNUNET_TIME_Absolute time;
1087 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1089 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
1092 GNUNET_free_non_null (my_ephemeral_key);
1093 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
1095 time = GNUNET_TIME_absolute_get ();
1096 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
1097 time = GNUNET_TIME_absolute_add (time, rekey_period);
1098 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
1099 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
1100 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
1102 GNUNET_assert (GNUNET_OK ==
1103 GNUNET_CRYPTO_eddsa_sign (my_private_key,
1105 &kx_msg.signature));
1107 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
1108 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
1110 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
1115 * Called only on shutdown, destroy every tunnel.
1117 * @param cls Closure (unused).
1118 * @param key Current public key.
1119 * @param value Value in the hash map (tunnel).
1121 * @return #GNUNET_YES, so we should continue to iterate,
1124 destroy_iterator (void *cls,
1125 const struct GNUNET_PeerIdentity *key,
1128 struct MeshTunnel3 *t = value;
1136 * Demultiplex data per channel and call appropriate channel handler.
1138 * @param t Tunnel on which the data came.
1139 * @param msg Data message.
1140 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1141 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1142 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1143 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1146 handle_data (struct MeshTunnel3 *t,
1147 const struct GNUNET_MESH_Data *msg,
1150 struct MeshChannel *ch;
1154 size = ntohs (msg->header.size);
1156 sizeof (struct GNUNET_MESH_Data) +
1157 sizeof (struct GNUNET_MessageHeader))
1162 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
1163 GM_m2s (ntohs (msg[1].header.type)));
1166 ch = GMT_get_channel (t, ntohl (msg->chid));
1169 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
1171 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel 0x%X unknown\n",
1176 GMCH_handle_data (ch, msg, fwd);
1181 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
1183 * @param t Tunnel on which the DATA ACK came.
1184 * @param msg DATA ACK message.
1185 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1186 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1187 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1188 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1191 handle_data_ack (struct MeshTunnel3 *t,
1192 const struct GNUNET_MESH_DataACK *msg,
1195 struct MeshChannel *ch;
1199 size = ntohs (msg->header.size);
1200 if (size != sizeof (struct GNUNET_MESH_DataACK))
1207 ch = GMT_get_channel (t, ntohl (msg->chid));
1210 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
1212 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1217 GMCH_handle_data_ack (ch, msg, fwd);
1222 * Handle channel create.
1224 * @param t Tunnel on which the data came.
1225 * @param msg Data message.
1228 handle_ch_create (struct MeshTunnel3 *t,
1229 const struct GNUNET_MESH_ChannelCreate *msg)
1231 struct MeshChannel *ch;
1235 size = ntohs (msg->header.size);
1236 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
1243 ch = GMT_get_channel (t, ntohl (msg->chid));
1244 if (NULL != ch && ! GMT_is_loopback (t))
1246 /* Probably a retransmission, safe to ignore */
1247 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
1251 ch = GMCH_handle_create (t, msg);
1254 GMT_add_channel (t, ch);
1260 * Handle channel NACK: check correctness and call channel handler for NACKs.
1262 * @param t Tunnel on which the NACK came.
1263 * @param msg NACK message.
1266 handle_ch_nack (struct MeshTunnel3 *t,
1267 const struct GNUNET_MESH_ChannelManage *msg)
1269 struct MeshChannel *ch;
1273 size = ntohs (msg->header.size);
1274 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1281 ch = GMT_get_channel (t, ntohl (msg->chid));
1284 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
1286 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1291 GMCH_handle_nack (ch);
1296 * Handle a CHANNEL ACK (SYNACK/ACK).
1298 * @param t Tunnel on which the CHANNEL ACK came.
1299 * @param msg CHANNEL ACK message.
1300 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1301 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1302 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1303 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1306 handle_ch_ack (struct MeshTunnel3 *t,
1307 const struct GNUNET_MESH_ChannelManage *msg,
1310 struct MeshChannel *ch;
1314 size = ntohs (msg->header.size);
1315 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1322 ch = GMT_get_channel (t, ntohl (msg->chid));
1325 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1327 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1332 GMCH_handle_ack (ch, msg, fwd);
1338 * Handle a channel destruction message.
1340 * @param t Tunnel on which the message came.
1341 * @param msg Channel destroy message.
1342 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1343 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1344 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1345 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1348 handle_ch_destroy (struct MeshTunnel3 *t,
1349 const struct GNUNET_MESH_ChannelManage *msg,
1352 struct MeshChannel *ch;
1356 size = ntohs (msg->header.size);
1357 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1364 ch = GMT_get_channel (t, ntohl (msg->chid));
1367 /* Probably a retransmission, safe to ignore */
1371 GMCH_handle_destroy (ch, msg, fwd);
1376 * The peer's ephemeral key has changed: update the symmetrical keys.
1378 * @param t Tunnel this message came on.
1379 * @param msg Key eXchange message.
1382 handle_ephemeral (struct MeshTunnel3 *t,
1383 const struct GNUNET_MESH_KX_Ephemeral *msg)
1385 struct GNUNET_HashCode km;
1386 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1388 if (GNUNET_OK != check_ephemeral (t, msg))
1390 GNUNET_break_op (0);
1393 derive_key_material (&km, &msg->ephemeral_key);
1394 LOG (GNUNET_ERROR_TYPE_DEBUG, " km is %s\n", GNUNET_h2s (&km));
1395 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1396 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1397 if (MESH_TUNNEL3_KEY_SENT == t->estate)
1399 LOG (GNUNET_ERROR_TYPE_DEBUG, " our key was sent, send ping\n");
1401 t->estate = MESH_TUNNEL3_KEY_PING;
1407 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1408 * Answer with by retransmitting the challenge with the "opposite" key.
1410 * @param t Tunnel this message came on.
1411 * @param msg Key eXchange Ping message.
1414 handle_ping (struct MeshTunnel3 *t,
1415 const struct GNUNET_MESH_KX_Ping *msg)
1417 struct GNUNET_MESH_KX_Ping res;
1419 if (ntohs (msg->header.size) != sizeof (res))
1421 GNUNET_break_op (0);
1425 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1426 t_decrypt (t, &res.target, &msg->target, ping_encryption_size (), msg->iv);
1427 if (0 != memcmp (&my_full_id, &res.target, sizeof (my_full_id)))
1429 GNUNET_break_op (0);
1430 LOG (GNUNET_ERROR_TYPE_DEBUG, " e got %u\n", msg->nonce);
1431 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg->target));
1432 LOG (GNUNET_ERROR_TYPE_DEBUG, " got %u\n", res.nonce);
1433 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&res.target));
1437 send_pong (t, res.nonce);
1442 * Peer has answer to our challenge.
1443 * If answer is successful, consider the key exchange finished and clean
1444 * up all related state.
1446 * @param t Tunnel this message came on.
1447 * @param msg Key eXchange Pong message.
1450 handle_pong (struct MeshTunnel3 *t,
1451 const struct GNUNET_MESH_KX_Pong *msg)
1455 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1456 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1458 GNUNET_STATISTICS_update (stats, "# duplicate PONG messages", 1, GNUNET_NO);
1461 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1463 if (challenge != t->kx_ctx->challenge)
1465 LOG (GNUNET_ERROR_TYPE_DEBUG,
1466 "Wrong PONG challenge: %u (e: %u). Expected: %u.\n",
1467 challenge, msg->nonce, t->kx_ctx->challenge);
1468 GNUNET_break_op (0);
1471 GNUNET_SCHEDULER_cancel (t->rekey_task);
1472 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1473 GNUNET_free (t->kx_ctx);
1475 GMT_change_estate (t, MESH_TUNNEL3_KEY_OK);
1480 * Demultiplex by message type and call appropriate handler for a message
1481 * towards a channel of a local tunnel.
1483 * @param t Tunnel this message came on.
1484 * @param msgh Message header.
1485 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1486 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1487 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1488 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1491 handle_decrypted (struct MeshTunnel3 *t,
1492 const struct GNUNET_MessageHeader *msgh,
1497 type = ntohs (msgh->type);
1498 LOG (GNUNET_ERROR_TYPE_DEBUG,
1499 "Got a %s message!\n",
1504 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1505 /* Don't send hop ACK, wait for client to ACK */
1506 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1509 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1510 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1513 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1514 handle_ch_create (t,
1515 (struct GNUNET_MESH_ChannelCreate *) msgh);
1518 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1520 (struct GNUNET_MESH_ChannelManage *) msgh);
1523 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1525 (struct GNUNET_MESH_ChannelManage *) msgh,
1529 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1530 handle_ch_destroy (t,
1531 (struct GNUNET_MESH_ChannelManage *) msgh,
1536 GNUNET_break_op (0);
1537 LOG (GNUNET_ERROR_TYPE_DEBUG,
1538 "end-to-end message not known (%u)\n",
1539 ntohs (msgh->type));
1543 /******************************************************************************/
1544 /******************************** API ***********************************/
1545 /******************************************************************************/
1548 * Decrypt and demultiplex by message type. Call appropriate handler
1549 * for every message.
1551 * @param t Tunnel this message came on.
1552 * @param msg Encrypted message.
1555 GMT_handle_encrypted (struct MeshTunnel3 *t,
1556 const struct GNUNET_MESH_Encrypted *msg)
1558 size_t size = ntohs (msg->header.size);
1559 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1560 size_t decrypted_size;
1561 char cbuf [payload_size];
1562 struct GNUNET_MessageHeader *msgh;
1565 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1567 while (off < decrypted_size)
1569 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1570 handle_decrypted (t, msgh, GNUNET_SYSERR);
1571 off += ntohs (msgh->size);
1577 * Demultiplex an encapsulated KX message by message type.
1579 * @param t Tunnel on which the message came.
1580 * @param message Payload of KX message.
1583 GMT_handle_kx (struct MeshTunnel3 *t,
1584 const struct GNUNET_MessageHeader *message)
1588 type = ntohs (message->type);
1589 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1592 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1593 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1596 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1597 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1600 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1601 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1605 GNUNET_break_op (0);
1606 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1612 * Initialize the tunnel subsystem.
1614 * @param c Configuration handle.
1615 * @param key ECC private key, to derive all other keys and do crypto.
1618 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1619 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1621 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1623 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1626 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1627 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1631 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1634 rekey_period = GNUNET_TIME_UNIT_DAYS;
1637 my_private_key = key;
1638 kx_msg.header.size = htons (sizeof (kx_msg));
1639 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1640 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1641 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1642 kx_msg.origin_identity = my_full_id;
1643 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1645 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1650 * Shut down the tunnel subsystem.
1655 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1657 GNUNET_SCHEDULER_cancel (rekey_task);
1658 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1660 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &destroy_iterator, NULL);
1661 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1668 * @param destination Peer this tunnel is towards.
1670 struct MeshTunnel3 *
1671 GMT_new (struct MeshPeer *destination)
1673 struct MeshTunnel3 *t;
1675 t = GNUNET_new (struct MeshTunnel3);
1677 t->peer = destination;
1680 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1681 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1692 * Change the tunnel's connection state.
1694 * @param t Tunnel whose connection state to change.
1695 * @param cstate New connection state.
1698 GMT_change_cstate (struct MeshTunnel3* t, enum MeshTunnel3CState cstate)
1702 LOG (GNUNET_ERROR_TYPE_DEBUG,
1703 "Tunnel %s cstate was %s\n",
1704 GMP_2s (t->peer), cstate2s (t->cstate));
1705 LOG (GNUNET_ERROR_TYPE_DEBUG,
1706 "Tunnel %s cstate is now %s\n",
1707 GMP_2s (t->peer), cstate2s (cstate));
1708 if (myid != GMP_get_short_id (t->peer) &&
1709 MESH_TUNNEL3_READY != t->cstate &&
1710 MESH_TUNNEL3_READY == cstate)
1713 if (MESH_TUNNEL3_KEY_OK == t->estate)
1715 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered send queued data\n");
1716 send_queued_data (t);
1718 else if (MESH_TUNNEL3_KEY_UNINITIALIZED == t->estate)
1720 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1721 rekey_tunnel (t, NULL);
1726 if (MESH_TUNNEL3_READY == cstate && 3 <= GMT_count_connections (t))
1728 GMP_stop_search (t->peer);
1733 * Change the tunnel encryption state.
1735 * @param t Tunnel whose encryption state to change.
1736 * @param state New encryption state.
1739 GMT_change_estate (struct MeshTunnel3* t, enum MeshTunnel3EState state)
1743 LOG (GNUNET_ERROR_TYPE_DEBUG,
1744 "Tunnel %s estate was %s\n",
1745 GMP_2s (t->peer), estate2s (t->estate));
1746 LOG (GNUNET_ERROR_TYPE_DEBUG,
1747 "Tunnel %s estate is now %s\n",
1748 GMP_2s (t->peer), estate2s (state));
1749 if (myid != GMP_get_short_id (t->peer) &&
1750 MESH_TUNNEL3_KEY_OK != t->estate && MESH_TUNNEL3_KEY_OK == state)
1753 send_queued_data (t);
1761 * Add a connection to a tunnel.
1764 * @param c Connection.
1767 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1769 struct MeshTConnection *aux;
1771 GNUNET_assert (NULL != c);
1773 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1777 aux = GNUNET_new (struct MeshTConnection);
1779 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1784 * Mark a path as no longer valid for this tunnel: has been tried and failed.
1786 * @param t Tunnel to update.
1787 * @param path Invalid path to remove. Is destroyed after removal.
1790 GMT_remove_path (struct MeshTunnel3 *t, struct MeshPeerPath *path)
1792 GMP_remove_path (t->peer, path);
1797 * Remove a connection from a tunnel.
1800 * @param c Connection.
1803 GMT_remove_connection (struct MeshTunnel3 *t,
1804 struct MeshConnection *c)
1806 struct MeshTConnection *aux;
1807 struct MeshTConnection *next;
1809 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing connection %s from tunnel %s\n",
1810 GMC_2s (c), GMT_2s (t));
1811 for (aux = t->connection_head; aux != NULL; aux = next)
1816 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1821 /* Start new connections if needed */
1822 if (NULL == t->connection_head
1823 && GNUNET_NO == t->destroy
1824 && GNUNET_NO == shutting_down)
1826 LOG (GNUNET_ERROR_TYPE_DEBUG, " no more connections, getting new ones\n");
1827 GMP_connect (t->peer);
1828 t->cstate = MESH_TUNNEL3_SEARCHING;
1832 /* If not marked as ready, no change is needed */
1833 if (MESH_TUNNEL3_READY != t->cstate)
1836 /* Check if any connection is ready to maintaing cstate */
1837 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1838 if (MESH_CONNECTION_READY == GMC_get_state (aux->c))
1841 t->cstate = MESH_TUNNEL3_WAITING;
1846 * Add a channel to a tunnel.
1849 * @param ch Channel.
1852 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1854 struct MeshTChannel *aux;
1856 GNUNET_assert (NULL != ch);
1858 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1860 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1862 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1867 aux = GNUNET_new (struct MeshTChannel);
1869 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1870 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1872 if (GNUNET_YES == t->destroy)
1874 t->destroy = GNUNET_NO;
1875 LOG (GNUNET_ERROR_TYPE_DEBUG, " undo destroy!\n");
1881 * Remove a channel from a tunnel.
1884 * @param ch Channel.
1887 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1889 struct MeshTChannel *aux;
1891 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1892 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1896 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1897 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1906 * Search for a channel by global ID.
1908 * @param t Tunnel containing the channel.
1909 * @param chid Public channel number.
1911 * @return channel handler, NULL if doesn't exist
1913 struct MeshChannel *
1914 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1916 struct MeshTChannel *iter;
1921 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1923 if (GMCH_get_id (iter->ch) == chid)
1927 return NULL == iter ? NULL : iter->ch;
1932 * Tunnel is empty: destroy it.
1934 * Notifies all connections about the destruction.
1936 * @param t Tunnel to destroy.
1939 GMT_destroy_empty (struct MeshTunnel3 *t)
1941 struct MeshTConnection *iter;
1943 LOG (GNUNET_ERROR_TYPE_DEBUG, "Tunnel %s empty: destroying scheduled\n",
1945 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1947 GMC_send_destroy (iter->c);
1950 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1952 t->estate = MESH_TUNNEL3_KEY_UNINITIALIZED;
1953 GNUNET_SCHEDULER_cancel (t->rekey_task);
1954 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1955 GNUNET_free (t->kx_ctx);
1958 t->cstate = MESH_TUNNEL3_NEW;
1959 t->destroy = GNUNET_YES;
1964 * Destroy tunnel if empty (no more channels).
1966 * @param t Tunnel to destroy if empty.
1969 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1971 if (1 < GMT_count_channels (t))
1974 GMT_destroy_empty (t);
1979 * Destroy the tunnel.
1981 * This function does not generate any warning traffic to clients or peers.
1984 * Cancel messages belonging to this tunnel queued to neighbors.
1985 * Free any allocated resources linked to the tunnel.
1987 * @param t The tunnel to destroy.
1990 GMT_destroy (struct MeshTunnel3 *t)
1992 struct MeshTConnection *iter_c;
1993 struct MeshTConnection *next_c;
1994 struct MeshTChannel *iter_ch;
1995 struct MeshTChannel *next_ch;
2002 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
2004 GNUNET_break (GNUNET_YES ==
2005 GNUNET_CONTAINER_multipeermap_remove (tunnels,
2006 GMP_get_id (t->peer), t));
2008 for (iter_c = t->connection_head; NULL != iter_c; iter_c = next_c)
2010 next_c = iter_c->next;
2011 GMC_destroy (iter_c->c);
2013 for (iter_ch = t->channel_head; NULL != iter_ch; iter_ch = next_ch)
2015 next_ch = iter_ch->next;
2016 GMCH_destroy (iter_ch->ch);
2017 /* Should only happen on shutdown, but it's ok. */
2020 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
2021 GMP_set_tunnel (t->peer, NULL);
2023 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
2024 GNUNET_SCHEDULER_cancel (t->rekey_task);
2031 * @brief Use the given path for the tunnel.
2032 * Update the next and prev hops (and RCs).
2033 * (Re)start the path refresh in case the tunnel is locally owned.
2035 * @param t Tunnel to update.
2036 * @param p Path to use.
2038 * @return Connection created.
2040 struct MeshConnection *
2041 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
2043 struct MeshConnection *c;
2044 struct GNUNET_HashCode cid;
2045 unsigned int own_pos;
2047 if (NULL == t || NULL == p)
2053 for (own_pos = 0; own_pos < p->length; own_pos++)
2055 if (p->peers[own_pos] == myid)
2058 if (own_pos > p->length - 1)
2060 GNUNET_break_op (0);
2064 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
2065 c = GMC_new (&cid, t, p, own_pos);
2068 /* Path was flawed */
2071 GMT_add_connection (t, c);
2077 * Count established (ready) connections of a tunnel.
2079 * @param t Tunnel on which to count.
2081 * @return Number of connections.
2084 GMT_count_connections (struct MeshTunnel3 *t)
2086 struct MeshTConnection *iter;
2089 for (count = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
2090 if (MESH_CONNECTION_DESTROYED != GMC_get_state (iter->c))
2097 * Count channels of a tunnel.
2099 * @param t Tunnel on which to count.
2101 * @return Number of channels.
2104 GMT_count_channels (struct MeshTunnel3 *t)
2106 struct MeshTChannel *iter;
2109 for (count = 0, iter = t->channel_head;
2111 iter = iter->next, count++) /* skip */;
2118 * Get the connectivity state of a tunnel.
2122 * @return Tunnel's connectivity state.
2124 enum MeshTunnel3CState
2125 GMT_get_cstate (struct MeshTunnel3 *t)
2130 return (enum MeshTunnel3CState) -1;
2137 * Get the maximum buffer space for a tunnel towards a local client.
2141 * @return Biggest buffer space offered by any channel in the tunnel.
2144 GMT_get_channels_buffer (struct MeshTunnel3 *t)
2146 struct MeshTChannel *iter;
2147 unsigned int buffer;
2148 unsigned int ch_buf;
2150 if (NULL == t->channel_head)
2152 /* Probably getting buffer for a channel create/handshake. */
2157 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2159 ch_buf = get_channel_buffer (iter);
2160 if (ch_buf > buffer)
2168 * Get the total buffer space for a tunnel for P2P traffic.
2172 * @return Buffer space offered by all connections in the tunnel.
2175 GMT_get_connections_buffer (struct MeshTunnel3 *t)
2177 struct MeshTConnection *iter;
2178 unsigned int buffer;
2181 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2183 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
2187 buffer += get_connection_buffer (iter);
2195 * Get the tunnel's destination.
2199 * @return ID of the destination peer.
2201 const struct GNUNET_PeerIdentity *
2202 GMT_get_destination (struct MeshTunnel3 *t)
2204 return GMP_get_id (t->peer);
2209 * Get the tunnel's next free global channel ID.
2213 * @return GID of a channel free to use.
2216 GMT_get_next_chid (struct MeshTunnel3 *t)
2218 MESH_ChannelNumber chid;
2219 MESH_ChannelNumber mask;
2222 /* Set bit 30 depending on the ID relationship. Bit 31 is always 0 for GID.
2223 * If our ID is bigger or loopback tunnel, start at 0, bit 30 = 0
2224 * If peer's ID is bigger, start at 0x4... bit 30 = 1
2226 result = GNUNET_CRYPTO_cmp_peer_identity (&my_full_id, GMP_get_id (t->peer));
2232 while (NULL != GMT_get_channel (t, t->next_chid))
2234 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
2235 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2236 t->next_chid |= mask;
2238 chid = t->next_chid;
2239 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2240 t->next_chid |= mask;
2247 * Send ACK on one or more channels due to buffer in connections.
2249 * @param t Channel which has some free buffer space.
2252 GMT_unchoke_channels (struct MeshTunnel3 *t)
2254 struct MeshTChannel *iter;
2255 unsigned int buffer;
2256 unsigned int channels = GMT_count_channels (t);
2257 unsigned int choked_n;
2258 struct MeshChannel *choked[channels];
2260 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
2261 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
2262 if (NULL != t->channel_head)
2263 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
2265 /* Get buffer space */
2266 buffer = GMT_get_connections_buffer (t);
2272 /* Count and remember choked channels */
2274 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2276 if (GNUNET_NO == get_channel_allowed (iter))
2278 choked[choked_n++] = iter->ch;
2282 /* Unchoke random channels */
2283 while (0 < buffer && 0 < choked_n)
2285 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2287 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
2290 choked[r] = choked[choked_n];
2296 * Send ACK on one or more connections due to buffer space to the client.
2298 * Iterates all connections of the tunnel and sends ACKs appropriately.
2303 GMT_send_connection_acks (struct MeshTunnel3 *t)
2305 struct MeshTConnection *iter;
2308 uint32_t allow_per_connection;
2310 unsigned int buffer;
2312 LOG (GNUNET_ERROR_TYPE_DEBUG, "Tunnel send connection ACKs on %s\n",
2321 buffer = GMT_get_channels_buffer (t);
2322 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer %u\n", buffer);
2324 /* Count connections, how many messages are already allowed */
2325 cs = GMT_count_connections (t);
2326 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
2328 allowed += get_connection_allowed (iter);
2330 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowed %u\n", allowed);
2332 /* Make sure there is no overflow */
2333 if (allowed > buffer)
2338 /* Authorize connections to send more data */
2339 to_allow = buffer; /* - allowed; */
2341 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
2343 allow_per_connection = to_allow/cs;
2344 to_allow -= allow_per_connection;
2346 if (get_connection_allowed (iter) > 64 / 3)
2350 GMC_allow (iter->c, allow_per_connection,
2351 GMC_is_origin (iter->c, GNUNET_NO));
2354 GNUNET_break (to_allow == 0);
2359 * Cancel a previously sent message while it's in the queue.
2361 * ONLY can be called before the continuation given to the send function
2362 * is called. Once the continuation is called, the message is no longer in the
2365 * @param q Handle to the queue.
2368 GMT_cancel (struct MeshTunnel3Queue *q)
2373 /* message_sent() will be called and free q */
2375 else if (NULL != q->tqd)
2377 unqueue_data (q->tqd);
2379 if (NULL != q->cont)
2380 q->cont (q->cont_cls, NULL, q, 0, 0);
2391 * Sends an already built message on a tunnel, encrypting it and
2392 * choosing the best connection.
2394 * @param message Message to send. Function modifies it.
2395 * @param t Tunnel on which this message is transmitted.
2396 * @param force Force the tunnel to take the message (buffer overfill).
2397 * @param cont Continuation to call once message is really sent.
2398 * @param cont_cls Closure for @c cont.
2400 * @return Handle to cancel message. NULL if @c cont is NULL.
2402 struct MeshTunnel3Queue *
2403 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2404 struct MeshTunnel3 *t, int force,
2405 GMT_sent cont, void *cont_cls)
2407 return send_prebuilt_message (message, t, force, cont, cont_cls, NULL);
2412 * Is the tunnel directed towards the local peer?
2416 * @return #GNUNET_YES if it is loopback.
2419 GMT_is_loopback (const struct MeshTunnel3 *t)
2421 return (myid == GMP_get_short_id (t->peer));
2426 * Is the tunnel this path already?
2431 * @return #GNUNET_YES a connection uses this path.
2434 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2436 struct MeshTConnection *iter;
2438 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2439 if (GMC_get_path (iter->c) == p)
2447 * Get a cost of a path for a tunnel considering existing connections.
2450 * @param path Candidate path.
2452 * @return Cost of the path (path length + number of overlapping nodes)
2455 GMT_get_path_cost (const struct MeshTunnel3 *t,
2456 const struct MeshPeerPath *path)
2458 struct MeshTConnection *iter;
2459 const struct MeshPeerPath *aux;
2460 unsigned int overlap;
2468 GNUNET_assert (NULL != t);
2470 for (i = 0; i < path->length; i++)
2472 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2474 aux = GMC_get_path (iter->c);
2478 for (j = 0; j < aux->length; j++)
2480 if (path->peers[i] == aux->peers[j])
2488 return (path->length + overlap) * (path->score * -1);
2493 * Get the static string for the peer this tunnel is directed.
2497 * @return Static string the destination peer's ID.
2500 GMT_2s (const struct MeshTunnel3 *t)
2505 return GMP_2s (t->peer);
2510 * Log all possible info about the tunnel state.
2512 * @param t Tunnel to debug.
2515 GMT_debug (const struct MeshTunnel3 *t)
2517 struct MeshTChannel *iterch;
2518 struct MeshTConnection *iterc;
2520 LOG (GNUNET_ERROR_TYPE_DEBUG, "DEBUG TUNNEL TOWARDS %s\n", GMT_2s (t));
2521 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate %s, estate %s\n",
2522 cstate2s (t->cstate), estate2s (t->estate));
2523 LOG (GNUNET_ERROR_TYPE_DEBUG, " kx_ctx %p, rekey_task %u\n",
2524 t->kx_ctx, t->rekey_task);
2525 LOG (GNUNET_ERROR_TYPE_DEBUG, " tq_head %p, tq_tail %p\n",
2526 t->tq_head, t->tq_tail);
2527 LOG (GNUNET_ERROR_TYPE_DEBUG, " destroy %u\n", t->destroy);
2529 LOG (GNUNET_ERROR_TYPE_DEBUG, " channels:\n");
2530 for (iterch = t->channel_head; NULL != iterch; iterch = iterch->next)
2532 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %s\n", GMCH_2s (iterch->ch));
2535 LOG (GNUNET_ERROR_TYPE_DEBUG, " connections:\n");
2536 for (iterc = t->connection_head; NULL != iterc; iterc = iterc->next)
2538 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %s [%u] buf: %u/%u (qn %u/%u)\n",
2539 GMC_2s (iterc->c), GMC_get_state (iterc->c),
2540 GMC_get_buffer (iterc->c, GNUNET_YES),
2541 GMC_get_buffer (iterc->c, GNUNET_NO),
2542 GMC_get_qn (iterc->c, GNUNET_YES),
2543 GMC_get_qn (iterc->c, GNUNET_NO));
2546 LOG (GNUNET_ERROR_TYPE_DEBUG, "DEBUG TUNNEL END\n");