2 This file is part of GNUnet.
3 (C) 2013 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 #include "gnunet_util_lib.h"
24 #include "gnunet_signatures.h"
25 #include "gnunet_statistics_service.h"
27 #include "mesh_protocol.h"
28 #include "mesh_path.h"
30 #include "gnunet-service-mesh_tunnel.h"
31 #include "gnunet-service-mesh_connection.h"
32 #include "gnunet-service-mesh_channel.h"
33 #include "gnunet-service-mesh_peer.h"
35 #define LOG(level, ...) GNUNET_log_from(level,"mesh-tun",__VA_ARGS__)
37 #define REKEY_WAIT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 5)
39 /******************************************************************************/
40 /******************************** STRUCTS **********************************/
41 /******************************************************************************/
45 struct MeshTChannel *next;
46 struct MeshTChannel *prev;
47 struct MeshChannel *ch;
50 struct MeshTConnection
52 struct MeshTConnection *next;
53 struct MeshTConnection *prev;
54 struct MeshConnection *c;
58 * Structure used during a Key eXchange.
60 struct MeshTunnelKXCtx
63 * Decryption ("their") old key, for decrypting traffic sent by the
64 * other end before the key exchange started.
66 struct GNUNET_CRYPTO_SymmetricSessionKey d_key_old;
69 * Challenge to send in a ping and expect in the pong.
75 * Struct containing all information regarding a tunnel to a peer.
80 * Endpoint of the tunnel.
82 struct MeshPeer *peer;
85 * State of the tunnel connectivity.
87 enum MeshTunnel3CState cstate;
90 * State of the tunnel encryption.
92 enum MeshTunnel3EState estate;
95 * Key eXchange context.
97 struct MeshTunnelKXCtx *kx_ctx;
100 * Encryption ("our") key.
102 struct GNUNET_CRYPTO_SymmetricSessionKey e_key;
105 * Decryption ("their") key.
107 struct GNUNET_CRYPTO_SymmetricSessionKey d_key;
110 * Task to start the rekey process.
112 GNUNET_SCHEDULER_TaskIdentifier rekey_task;
115 * Paths that are actively used to reach the destination peer.
117 struct MeshTConnection *connection_head;
118 struct MeshTConnection *connection_tail;
121 * Next connection number.
126 * Channels inside this tunnel.
128 struct MeshTChannel *channel_head;
129 struct MeshTChannel *channel_tail;
132 * Channel ID for the next created channel.
134 MESH_ChannelNumber next_chid;
137 * Destroy flag: if true, destroy on last message.
142 * Queued messages, to transmit once tunnel gets connected.
144 struct MeshTunnelDelayed *tq_head;
145 struct MeshTunnelDelayed *tq_tail;
150 * Struct used to save messages in a non-ready tunnel to send once connected.
152 struct MeshTunnelDelayed
157 struct MeshTunnelDelayed *next;
158 struct MeshTunnelDelayed *prev;
163 struct MeshTunnel3 *t;
166 * Tunnel queue given to the channel to cancel request. Update on send_queued.
168 struct MeshTunnel3Queue *tq;
173 /* struct GNUNET_MessageHeader *msg; */
178 * Handle for messages queued but not yet sent.
180 struct MeshTunnel3Queue
183 * Connection queue handle, to cancel if necessary.
185 struct MeshConnectionQueue *cq;
188 * Handle in case message hasn't been given to a connection yet.
190 struct MeshTunnelDelayed *tqd;
193 * Continuation to call once sent.
198 * Closure for @c cont.
204 /******************************************************************************/
205 /******************************* GLOBALS ***********************************/
206 /******************************************************************************/
209 * Global handle to the statistics service.
211 extern struct GNUNET_STATISTICS_Handle *stats;
214 * Local peer own ID (memory efficient handle).
216 extern GNUNET_PEER_Id myid;
219 * Local peer own ID (full value).
221 extern struct GNUNET_PeerIdentity my_full_id;
225 * Set of all tunnels, in order to trigger a new exchange on rekey.
226 * Indexed by peer's ID.
228 static struct GNUNET_CONTAINER_MultiPeerMap *tunnels;
231 * Default TTL for payload packets.
233 static unsigned long long default_ttl;
238 const static struct GNUNET_CRYPTO_EddsaPrivateKey *my_private_key;
241 * Own ephemeral private key.
243 static struct GNUNET_CRYPTO_EcdhePrivateKey *my_ephemeral_key;
246 * Cached message used to perform a key exchange.
248 static struct GNUNET_MESH_KX_Ephemeral kx_msg;
251 * Task to generate a new ephemeral key.
253 static GNUNET_SCHEDULER_TaskIdentifier rekey_task;
258 static struct GNUNET_TIME_Relative rekey_period;
260 /******************************************************************************/
261 /******************************** STATIC ***********************************/
262 /******************************************************************************/
265 * Get string description for tunnel connectivity state.
267 * @param cs Tunnel state.
269 * @return String representation.
272 cstate2s (enum MeshTunnel3CState cs)
274 static char buf[128];
278 case MESH_TUNNEL3_NEW:
279 return "MESH_TUNNEL3_NEW";
280 case MESH_TUNNEL3_SEARCHING:
281 return "MESH_TUNNEL3_SEARCHING";
282 case MESH_TUNNEL3_WAITING:
283 return "MESH_TUNNEL3_WAITING";
284 case MESH_TUNNEL3_READY:
285 return "MESH_TUNNEL3_READY";
288 sprintf (buf, "%u (UNKNOWN STATE)", cs);
296 * Get string description for tunnel encryption state.
298 * @param es Tunnel state.
300 * @return String representation.
303 estate2s (enum MeshTunnel3EState es)
305 static char buf[128];
309 case MESH_TUNNEL3_KEY_UNINITIALIZED:
310 return "MESH_TUNNEL3_KEY_UNINITIALIZED";
311 case MESH_TUNNEL3_KEY_SENT:
312 return "MESH_TUNNEL3_KEY_SENT";
313 case MESH_TUNNEL3_KEY_PING:
314 return "MESH_TUNNEL3_KEY_PING";
315 case MESH_TUNNEL3_KEY_OK:
316 return "MESH_TUNNEL3_KEY_OK";
319 sprintf (buf, "%u (UNKNOWN STATE)", es);
327 * @brief Check if tunnel is ready to send traffic.
329 * Tunnel must be connected and with encryption correctly set up.
331 * @param t Tunnel to check.
333 * @return #GNUNET_YES if ready, #GNUNET_NO otherwise
336 is_ready (struct MeshTunnel3 *t)
338 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready: cs=%s, es=%s\n",
339 cstate2s (t->cstate), estate2s (t->estate));
340 return (MESH_TUNNEL3_READY == t->cstate
341 && MESH_TUNNEL3_KEY_OK == t->estate)
342 || GMT_is_loopback (t);
347 * Ephemeral key message purpose size.
349 * @return Size of the part of the ephemeral key message that must be signed.
352 ephemeral_purpose_size (void)
354 return sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
355 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
356 sizeof (struct GNUNET_TIME_AbsoluteNBO) +
357 sizeof (struct GNUNET_CRYPTO_EcdhePublicKey) +
358 sizeof (struct GNUNET_PeerIdentity);
363 * Size of the encrypted part of a ping message.
365 * @return Size of the encrypted part of a ping message.
368 ping_encryption_size (void)
370 return sizeof (struct GNUNET_PeerIdentity) + sizeof (uint32_t);
375 * Get the channel's buffer. ONLY FOR NON-LOOPBACK CHANNELS!!
377 * @param tch Tunnel's channel handle.
379 * @return Amount of messages the channel can still buffer towards the client.
382 get_channel_buffer (const struct MeshTChannel *tch)
386 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
387 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
389 return GMCH_get_buffer (tch->ch, fwd);
394 * Get the channel's allowance status.
396 * @param tch Tunnel's channel handle.
398 * @return #GNUNET_YES if we allowed the client to send data to us.
401 get_channel_allowed (const struct MeshTChannel *tch)
405 /* If channel is outgoing, is origin in the FWD direction and fwd is YES */
406 fwd = GMCH_is_origin (tch->ch, GNUNET_YES);
408 return GMCH_get_allowed (tch->ch, fwd);
413 * Get the connection's buffer.
415 * @param tc Tunnel's connection handle.
417 * @return Amount of messages the connection can still buffer.
420 get_connection_buffer (const struct MeshTConnection *tc)
424 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
425 fwd = GMC_is_origin (tc->c, GNUNET_YES);
427 return GMC_get_buffer (tc->c, fwd);
432 * Get the connection's allowance.
434 * @param tc Tunnel's connection handle.
436 * @return Amount of messages we have allowed the next peer to send us.
439 get_connection_allowed (const struct MeshTConnection *tc)
443 /* If connection is outgoing, is origin in the FWD direction and fwd is YES */
444 fwd = GMC_is_origin (tc->c, GNUNET_YES);
446 return GMC_get_allowed (tc->c, fwd);
451 * Check that a ephemeral key message s well formed and correctly signed.
453 * @param t Tunnel on which the message came.
454 * @param msg The ephemeral key message.
456 * @return GNUNET_OK if message is fine, GNUNET_SYSERR otherwise.
459 check_ephemeral (struct MeshTunnel3 *t,
460 const struct GNUNET_MESH_KX_Ephemeral *msg)
462 /* Check message size */
463 if (ntohs (msg->header.size) != sizeof (struct GNUNET_MESH_KX_Ephemeral))
464 return GNUNET_SYSERR;
466 /* Check signature size */
467 if (ntohl (msg->purpose.size) != ephemeral_purpose_size ())
468 return GNUNET_SYSERR;
471 if (0 != memcmp (&msg->origin_identity,
472 GMP_get_id (t->peer),
473 sizeof (struct GNUNET_PeerIdentity)))
474 return GNUNET_SYSERR;
476 /* Check signature */
478 GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_MESH_KX,
481 &msg->origin_identity.public_key))
482 return GNUNET_SYSERR;
489 * Encrypt data with the tunnel key.
491 * @param t Tunnel whose key to use.
492 * @param dst Destination for the encrypted data.
493 * @param src Source of the plaintext. Can overlap with @c dst.
494 * @param size Size of the plaintext.
495 * @param iv Initialization Vector to use.
498 t_encrypt (struct MeshTunnel3 *t,
499 void *dst, const void *src,
500 size_t size, uint32_t iv)
502 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
504 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->e_key, &iv, sizeof (uint32_t), NULL);
505 return GNUNET_CRYPTO_symmetric_encrypt (src, size, &t->e_key, &siv, dst);
510 * Decrypt data with the tunnel key.
512 * @param t Tunnel whose key to use.
513 * @param dst Destination for the plaintext.
514 * @param src Source of the encrypted data. Can overlap with @c dst.
515 * @param size Size of the encrypted data.
516 * @param iv Initialization Vector to use.
519 t_decrypt (struct MeshTunnel3 *t,
520 void *dst, const void *src,
521 size_t size, uint32_t iv)
523 struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
525 GNUNET_CRYPTO_symmetric_derive_iv (&siv, &t->d_key, &iv, sizeof (uint32_t), NULL);
526 return GNUNET_CRYPTO_symmetric_decrypt (src, size, &t->d_key, &siv, dst);
531 * Create key material by doing ECDH on the local and remote ephemeral keys.
533 * @param key_material Where to store the key material.
534 * @param ephemeral_key Peer's public ephemeral key.
537 derive_key_material (struct GNUNET_HashCode *key_material,
538 const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key)
541 GNUNET_CRYPTO_ecc_ecdh (my_ephemeral_key,
550 * Create a symmetic key from the identities of both ends and the key material
553 * @param key Destination for the generated key.
554 * @param sender ID of the peer that will encrypt with @c key.
555 * @param receiver ID of the peer that will decrypt with @c key.
556 * @param key_material Hash created with ECDH with the ephemeral keys.
559 derive_symmertic (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
560 const struct GNUNET_PeerIdentity *sender,
561 const struct GNUNET_PeerIdentity *receiver,
562 const struct GNUNET_HashCode *key_material)
564 const char salt[] = "MESH kx salt";
566 GNUNET_CRYPTO_kdf (key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
568 key_material, sizeof (struct GNUNET_HashCode),
569 sender, sizeof (struct GNUNET_PeerIdentity),
570 receiver, sizeof (struct GNUNET_PeerIdentity),
575 * Pick a connection on which send the next data message.
577 * @param t Tunnel on which to send the message.
579 * @return The connection on which to send the next message.
581 static struct MeshConnection *
582 tunnel_get_connection (struct MeshTunnel3 *t)
584 struct MeshTConnection *iter;
585 struct MeshConnection *best;
587 unsigned int lowest_q;
589 LOG (GNUNET_ERROR_TYPE_DEBUG, "tunnel_get_connection %s\n", GMP_2s (t->peer));
592 for (iter = t->connection_head; NULL != iter; iter = iter->next)
594 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s: %u\n",
595 GMC_2s (iter->c), GMC_get_state (iter->c));
596 if (MESH_CONNECTION_READY == GMC_get_state (iter->c))
598 qn = GMC_get_qn (iter->c, GMC_is_origin (iter->c, GNUNET_YES));
599 LOG (GNUNET_ERROR_TYPE_DEBUG, " q_n %u, \n", qn);
607 LOG (GNUNET_ERROR_TYPE_DEBUG, " selected: connection %s\n", GMC_2s (best));
613 * Callback called when a queued message is sent.
615 * Calculates the average time and connection packet tracking.
617 * @param cls Closure (TunnelQueue handle).
618 * @param c Connection this message was on.
619 * @param q Connection queue handle (unused).
620 * @param type Type of message sent.
621 * @param fwd Was this a FWD going message?
622 * @param size Size of the message.
625 message_sent (void *cls,
626 struct MeshConnection *c,
627 struct MeshConnectionQueue *q,
628 uint16_t type, int fwd, size_t size)
630 struct MeshTunnel3Queue *qt = cls;
632 GNUNET_assert (NULL != qt->cont);
633 qt->cont (qt->cont_cls, GMC_get_tunnel (c), qt, type, size);
639 * Delete a queued message: either was sent or the channel was destroyed
640 * before the tunnel's key exchange had a chance to finish.
642 * @param tq Queue handle.
645 unqueue_data (struct MeshTunnelDelayed *tq)
647 GNUNET_CONTAINER_DLL_remove (tq->t->tq_head, tq->t->tq_tail, tq);
653 * Cache a message to be sent once tunnel is online.
655 * @param t Tunnel to hold the message.
656 * @param msg Message itself (copy will be made).
658 static struct MeshTunnelDelayed *
659 queue_data (struct MeshTunnel3 *t, const struct GNUNET_MessageHeader *msg)
661 struct MeshTunnelDelayed *tqd;
662 uint16_t size = ntohs (msg->size);
664 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue data on Tunnel %s\n", GMT_2s (t));
666 if (GNUNET_YES == is_ready (t))
672 tqd = GNUNET_malloc (sizeof (struct MeshTunnelDelayed) + size);
675 memcpy (&tqd[1], msg, size);
676 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tqd);
683 * Sends an already built message on a tunnel, encrypting it and
684 * choosing the best connection.
686 * @param message Message to send. Function modifies it.
687 * @param t Tunnel on which this message is transmitted.
688 * @param force Force the tunnel to take the message (buffer overfill).
689 * @param cont Continuation to call once message is really sent.
690 * @param cont_cls Closure for @c cont.
691 * @param existing_q In case this a transmission of previously queued data,
692 * this should be TunnelQueue given to the client.
695 * @return Handle to cancel message. NULL if @c cont is NULL.
697 static struct MeshTunnel3Queue *
698 send_prebuilt_message (const struct GNUNET_MessageHeader *message,
699 struct MeshTunnel3 *t, int force,
700 GMT_sent cont, void *cont_cls,
701 struct MeshTunnel3Queue *existing_q)
703 struct MeshTunnel3Queue *tq;
704 struct MeshConnection *c;
705 struct GNUNET_MESH_Encrypted *msg;
706 size_t size = ntohs (message->size);
707 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
712 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
714 if (GNUNET_NO == is_ready (t))
716 struct MeshTunnelDelayed *tqd;
717 /* A non null existing_q indicates sending of queued data.
718 * Should only happen after tunnel becomes ready.
720 GNUNET_assert (NULL == existing_q);
721 tqd = queue_data (t, message);
724 tq = GNUNET_new (struct MeshTunnel3Queue);
728 tq->cont_cls = cont_cls;
732 GNUNET_assert (GNUNET_NO == GMT_is_loopback (t));
734 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
735 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
736 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
738 GNUNET_assert (t_encrypt (t, &msg[1], message, size, iv) == size);
739 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + size);
740 c = tunnel_get_connection (t);
743 GNUNET_break (GNUNET_YES == t->destroy);
746 type = ntohs (message->type);
749 case GNUNET_MESSAGE_TYPE_MESH_DATA:
750 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
751 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
752 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
753 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
754 msg->cid = *GMC_get_id (c);
755 msg->ttl = htonl (default_ttl);
758 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
763 fwd = GMC_is_origin (c, GNUNET_YES);
767 (void) GMC_send_prebuilt_message (&msg->header, c, fwd, force, NULL, NULL);
770 if (NULL == existing_q)
772 tq = GNUNET_new (struct MeshTunnel3Queue); /* FIXME valgrind: leak*/
779 tq->cq = GMC_send_prebuilt_message (&msg->header, c, fwd, force,
782 tq->cont_cls = cont_cls;
789 * Send all cached messages that we can, tunnel is online.
791 * @param t Tunnel that holds the messages. Cannot be loopback.
794 send_queued_data (struct MeshTunnel3 *t)
796 struct MeshTunnelDelayed *tqd;
797 struct MeshTunnelDelayed *next;
800 LOG (GNUNET_ERROR_TYPE_DEBUG,
801 "GMT_send_queued_data on tunnel %s\n",
804 if (GMT_is_loopback (t))
810 if (GNUNET_NO == is_ready (t))
812 LOG (GNUNET_ERROR_TYPE_DEBUG, " not ready yet: %s/%s\n",
813 estate2s (t->estate), cstate2s (t->cstate));
817 room = GMT_get_connections_buffer (t);
818 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
819 LOG (GNUNET_ERROR_TYPE_DEBUG, " tq head: %p\n", t->tq_head);
820 for (tqd = t->tq_head; NULL != tqd && room > 0; tqd = next)
822 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending queued data\n");
825 send_prebuilt_message ((struct GNUNET_MessageHeader *) &tqd[1],
827 NULL != tqd->tq ? tqd->tq->cont : NULL,
828 NULL != tqd->tq ? tqd->tq->cont_cls : NULL,
832 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_send_queued_data end\n", GMP_2s (t->peer));
837 * Sends key exchange message on a tunnel, choosing the best connection.
838 * Should not be called on loopback tunnels.
840 * @param t Tunnel on which this message is transmitted.
841 * @param message Message to send. Function modifies it.
844 send_kx (struct MeshTunnel3 *t,
845 const struct GNUNET_MessageHeader *message)
847 struct MeshConnection *c;
848 struct GNUNET_MESH_KX *msg;
849 size_t size = ntohs (message->size);
850 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
854 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
856 /* Avoid loopback. */
857 if (GMT_is_loopback (t))
859 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
864 /* Must have a connection. */
865 if (NULL == t->connection_head)
867 GNUNET_break (MESH_TUNNEL3_SEARCHING == t->cstate);
871 msg = (struct GNUNET_MESH_KX *) cbuf;
872 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
873 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
874 c = tunnel_get_connection (t);
877 GNUNET_break (GNUNET_YES == t->destroy || MESH_TUNNEL3_READY != t->cstate);
880 type = ntohs (message->type);
883 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
884 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
885 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
886 msg->reserved = htonl (0);
887 memcpy (&msg[1], message, size);
890 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
895 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
896 /* TODO save handle and cancel in case of a unneeded retransmission */
897 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
902 * Send the ephemeral key on a tunnel.
904 * @param t Tunnel on which to send the key.
907 send_ephemeral (struct MeshTunnel3 *t)
909 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
911 kx_msg.sender_status = htonl (t->estate);
912 send_kx (t, &kx_msg.header);
916 * Send a ping message on a tunnel.
918 * @param t Tunnel on which to send the ping.
921 send_ping (struct MeshTunnel3 *t)
923 struct GNUNET_MESH_KX_Ping msg;
925 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
926 msg.header.size = htons (sizeof (msg));
927 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
928 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
929 msg.target = *GMP_get_id (t->peer);
930 msg.nonce = t->kx_ctx->challenge;
932 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
933 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&msg.target));
934 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
935 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
936 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg.target));
938 send_kx (t, &msg.header);
943 * Send a pong message on a tunnel.
945 * @param t Tunnel on which to send the pong.
946 * @param challenge Value sent in the ping that we have to send back.
949 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
951 struct GNUNET_MESH_KX_Pong msg;
953 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
954 msg.header.size = htons (sizeof (msg));
955 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
956 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
957 msg.nonce = challenge;
958 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
959 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
960 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
962 send_kx (t, &msg.header);
967 * Initiate a rekey with the remote peer.
969 * @param cls Closure (tunnel).
970 * @param tc TaskContext.
973 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
975 struct MeshTunnel3 *t = cls;
977 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
979 LOG (GNUNET_ERROR_TYPE_DEBUG, "Re-key Tunnel\n");
980 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
983 if (NULL == t->kx_ctx)
985 LOG (GNUNET_ERROR_TYPE_DEBUG, " new kx ctx\n");
986 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
987 t->kx_ctx->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
989 t->kx_ctx->d_key_old = t->d_key;
994 case MESH_TUNNEL3_KEY_UNINITIALIZED:
995 t->estate = MESH_TUNNEL3_KEY_SENT;
997 case MESH_TUNNEL3_KEY_SENT:
999 case MESH_TUNNEL3_KEY_PING:
1000 case MESH_TUNNEL3_KEY_OK:
1002 t->estate = MESH_TUNNEL3_KEY_PING;
1005 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->estate);
1008 LOG (GNUNET_ERROR_TYPE_DEBUG, " next call in %s\n",
1009 GNUNET_STRINGS_relative_time_to_string (REKEY_WAIT, GNUNET_YES));
1010 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
1015 * Out ephemeral key has changed, create new session key on all tunnels.
1017 * @param cls Closure (size of the hashmap).
1018 * @param key Current public key.
1019 * @param value Value in the hash map (tunnel).
1021 * @return #GNUNET_YES, so we should continue to iterate,
1024 rekey_iterator (void *cls,
1025 const struct GNUNET_PeerIdentity *key,
1028 struct MeshTunnel3 *t = value;
1029 struct GNUNET_TIME_Relative delay;
1030 long n = (long) cls;
1033 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1036 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
1037 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
1038 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
1045 * Create a new ephemeral key and key message, schedule next rekeying.
1047 * @param cls Closure (unused).
1048 * @param tc TaskContext.
1051 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1053 struct GNUNET_TIME_Absolute time;
1056 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1058 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
1061 GNUNET_free_non_null (my_ephemeral_key);
1062 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
1064 time = GNUNET_TIME_absolute_get ();
1065 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
1066 time = GNUNET_TIME_absolute_add (time, rekey_period);
1067 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
1068 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
1069 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
1071 GNUNET_assert (GNUNET_OK ==
1072 GNUNET_CRYPTO_eddsa_sign (my_private_key,
1074 &kx_msg.signature));
1076 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
1077 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
1079 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
1084 * Called only on shutdown, destroy every tunnel.
1086 * @param cls Closure (unused).
1087 * @param key Current public key.
1088 * @param value Value in the hash map (tunnel).
1090 * @return #GNUNET_YES, so we should continue to iterate,
1093 destroy_iterator (void *cls,
1094 const struct GNUNET_PeerIdentity *key,
1097 struct MeshTunnel3 *t = value;
1105 * Demultiplex data per channel and call appropriate channel handler.
1107 * @param t Tunnel on which the data came.
1108 * @param msg Data message.
1109 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1110 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1111 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1112 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1115 handle_data (struct MeshTunnel3 *t,
1116 const struct GNUNET_MESH_Data *msg,
1119 struct MeshChannel *ch;
1123 size = ntohs (msg->header.size);
1125 sizeof (struct GNUNET_MESH_Data) +
1126 sizeof (struct GNUNET_MessageHeader))
1131 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
1132 GM_m2s (ntohs (msg[1].header.type)));
1135 ch = GMT_get_channel (t, ntohl (msg->chid));
1138 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
1140 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1145 GMCH_handle_data (ch, msg, fwd);
1150 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
1152 * @param t Tunnel on which the DATA ACK came.
1153 * @param msg DATA ACK message.
1154 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1155 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1156 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1157 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1160 handle_data_ack (struct MeshTunnel3 *t,
1161 const struct GNUNET_MESH_DataACK *msg,
1164 struct MeshChannel *ch;
1168 size = ntohs (msg->header.size);
1169 if (size != sizeof (struct GNUNET_MESH_DataACK))
1176 ch = GMT_get_channel (t, ntohl (msg->chid));
1179 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
1181 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1186 GMCH_handle_data_ack (ch, msg, fwd);
1191 * Handle channel create.
1193 * @param t Tunnel on which the data came.
1194 * @param msg Data message.
1197 handle_ch_create (struct MeshTunnel3 *t,
1198 const struct GNUNET_MESH_ChannelCreate *msg)
1200 struct MeshChannel *ch;
1204 size = ntohs (msg->header.size);
1205 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
1212 ch = GMT_get_channel (t, ntohl (msg->chid));
1213 if (NULL != ch && ! GMT_is_loopback (t))
1215 /* Probably a retransmission, safe to ignore */
1216 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
1220 ch = GMCH_handle_create (t, msg);
1223 GMT_add_channel (t, ch);
1229 * Handle channel NACK: check correctness and call channel handler for NACKs.
1231 * @param t Tunnel on which the NACK came.
1232 * @param msg NACK message.
1235 handle_ch_nack (struct MeshTunnel3 *t,
1236 const struct GNUNET_MESH_ChannelManage *msg)
1238 struct MeshChannel *ch;
1242 size = ntohs (msg->header.size);
1243 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1250 ch = GMT_get_channel (t, ntohl (msg->chid));
1253 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
1255 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1260 GMCH_handle_nack (ch);
1265 * Handle a CHANNEL ACK (SYNACK/ACK).
1267 * @param t Tunnel on which the CHANNEL ACK came.
1268 * @param msg CHANNEL ACK message.
1269 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1270 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1271 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1272 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1275 handle_ch_ack (struct MeshTunnel3 *t,
1276 const struct GNUNET_MESH_ChannelManage *msg,
1279 struct MeshChannel *ch;
1283 size = ntohs (msg->header.size);
1284 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1291 ch = GMT_get_channel (t, ntohl (msg->chid));
1294 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1296 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1301 GMCH_handle_ack (ch, msg, fwd);
1307 * Handle a channel destruction message.
1309 * @param t Tunnel on which the message came.
1310 * @param msg Channel destroy message.
1311 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1312 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1313 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1314 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1317 handle_ch_destroy (struct MeshTunnel3 *t,
1318 const struct GNUNET_MESH_ChannelManage *msg,
1321 struct MeshChannel *ch;
1325 size = ntohs (msg->header.size);
1326 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1333 ch = GMT_get_channel (t, ntohl (msg->chid));
1336 /* Probably a retransmission, safe to ignore */
1340 GMCH_handle_destroy (ch, msg, fwd);
1345 * The peer's ephemeral key has changed: update the symmetrical keys.
1347 * @param t Tunnel this message came on.
1348 * @param msg Key eXchange message.
1351 handle_ephemeral (struct MeshTunnel3 *t,
1352 const struct GNUNET_MESH_KX_Ephemeral *msg)
1354 struct GNUNET_HashCode km;
1355 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1357 if (GNUNET_OK != check_ephemeral (t, msg))
1359 GNUNET_break_op (0);
1362 derive_key_material (&km, &msg->ephemeral_key);
1363 LOG (GNUNET_ERROR_TYPE_DEBUG, " km is %s\n", GNUNET_h2s (&km));
1364 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1365 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1366 if (MESH_TUNNEL3_KEY_SENT == t->estate)
1368 LOG (GNUNET_ERROR_TYPE_DEBUG, " our key was sent, send ping\n");
1370 t->estate = MESH_TUNNEL3_KEY_PING;
1376 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1377 * Answer with by retransmitting the challenge with the "opposite" key.
1379 * @param t Tunnel this message came on.
1380 * @param msg Key eXchange Ping message.
1383 handle_ping (struct MeshTunnel3 *t,
1384 const struct GNUNET_MESH_KX_Ping *msg)
1386 struct GNUNET_MESH_KX_Ping res;
1388 if (ntohs (msg->header.size) != sizeof (res))
1390 GNUNET_break_op (0);
1394 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1395 t_decrypt (t, &res.target, &msg->target, ping_encryption_size (), msg->iv);
1396 if (0 != memcmp (&my_full_id, &res.target, sizeof (my_full_id)))
1398 GNUNET_break_op (0);
1399 LOG (GNUNET_ERROR_TYPE_DEBUG, " e got %u\n", msg->nonce);
1400 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg->target));
1401 LOG (GNUNET_ERROR_TYPE_DEBUG, " got %u\n", res.nonce);
1402 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&res.target));
1406 send_pong (t, res.nonce);
1411 * Peer has answer to our challenge.
1412 * If answer is successful, consider the key exchange finished and clean
1413 * up all related state.
1415 * @param t Tunnel this message came on.
1416 * @param msg Key eXchange Pong message.
1419 handle_pong (struct MeshTunnel3 *t,
1420 const struct GNUNET_MESH_KX_Pong *msg)
1424 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1425 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1427 GNUNET_break_op (0);
1430 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1432 if (challenge != t->kx_ctx->challenge)
1434 LOG (GNUNET_ERROR_TYPE_DEBUG,
1435 "Wrong PONG challenge: %u (e: %u). Expected: %u.\n",
1436 challenge, msg->nonce, t->kx_ctx->challenge);
1437 GNUNET_break_op (0);
1440 GNUNET_SCHEDULER_cancel (t->rekey_task);
1441 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1442 GNUNET_free (t->kx_ctx);
1444 GMT_change_estate (t, MESH_TUNNEL3_KEY_OK);
1449 * Demultiplex by message type and call appropriate handler for a message
1450 * towards a channel of a local tunnel.
1452 * @param t Tunnel this message came on.
1453 * @param msgh Message header.
1454 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1455 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1456 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1457 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1460 handle_decrypted (struct MeshTunnel3 *t,
1461 const struct GNUNET_MessageHeader *msgh,
1466 type = ntohs (msgh->type);
1467 LOG (GNUNET_ERROR_TYPE_DEBUG,
1468 "Got a %s message!\n",
1473 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1474 /* Don't send hop ACK, wait for client to ACK */
1475 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1478 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1479 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1482 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1483 handle_ch_create (t,
1484 (struct GNUNET_MESH_ChannelCreate *) msgh);
1487 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1489 (struct GNUNET_MESH_ChannelManage *) msgh);
1492 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1494 (struct GNUNET_MESH_ChannelManage *) msgh,
1498 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1499 handle_ch_destroy (t,
1500 (struct GNUNET_MESH_ChannelManage *) msgh,
1505 GNUNET_break_op (0);
1506 LOG (GNUNET_ERROR_TYPE_DEBUG,
1507 "end-to-end message not known (%u)\n",
1508 ntohs (msgh->type));
1512 /******************************************************************************/
1513 /******************************** API ***********************************/
1514 /******************************************************************************/
1517 * Decrypt and demultiplex by message type. Call appropriate handler
1518 * for every message.
1520 * @param t Tunnel this message came on.
1521 * @param msg Encrypted message.
1524 GMT_handle_encrypted (struct MeshTunnel3 *t,
1525 const struct GNUNET_MESH_Encrypted *msg)
1527 size_t size = ntohs (msg->header.size);
1528 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1529 size_t decrypted_size;
1530 char cbuf [payload_size];
1531 struct GNUNET_MessageHeader *msgh;
1534 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1536 while (off < decrypted_size)
1538 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1539 handle_decrypted (t, msgh, GNUNET_SYSERR);
1540 off += ntohs (msgh->size);
1546 * Demultiplex an encapsulated KX message by message type.
1548 * @param t Tunnel on which the message came.
1549 * @param message Payload of KX message.
1552 GMT_handle_kx (struct MeshTunnel3 *t,
1553 const struct GNUNET_MessageHeader *message)
1557 type = ntohs (message->type);
1558 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1561 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1562 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1565 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1566 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1569 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1570 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1574 GNUNET_break_op (0);
1575 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1581 * Initialize the tunnel subsystem.
1583 * @param c Configuration handle.
1584 * @param key ECC private key, to derive all other keys and do crypto.
1587 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1588 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1590 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1592 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1595 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1596 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1600 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1603 rekey_period = GNUNET_TIME_UNIT_DAYS;
1606 my_private_key = key;
1607 kx_msg.header.size = htons (sizeof (kx_msg));
1608 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1609 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1610 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1611 kx_msg.origin_identity = my_full_id;
1612 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1614 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1619 * Shut down the tunnel subsystem.
1624 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1626 GNUNET_SCHEDULER_cancel (rekey_task);
1627 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1629 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &destroy_iterator, NULL);
1630 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1637 * @param destination Peer this tunnel is towards.
1639 struct MeshTunnel3 *
1640 GMT_new (struct MeshPeer *destination)
1642 struct MeshTunnel3 *t;
1644 t = GNUNET_new (struct MeshTunnel3);
1646 t->peer = destination;
1649 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1650 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1661 * Change the tunnel's connection state.
1663 * @param t Tunnel whose connection state to change.
1664 * @param cstate New connection state.
1667 GMT_change_cstate (struct MeshTunnel3* t, enum MeshTunnel3CState cstate)
1671 LOG (GNUNET_ERROR_TYPE_DEBUG,
1672 "Tunnel %s cstate was %s\n",
1673 GMP_2s (t->peer), cstate2s (t->cstate));
1674 LOG (GNUNET_ERROR_TYPE_DEBUG,
1675 "Tunnel %s cstate is now %s\n",
1676 GMP_2s (t->peer), cstate2s (cstate));
1677 if (myid != GMP_get_short_id (t->peer) &&
1678 MESH_TUNNEL3_READY != t->cstate &&
1679 MESH_TUNNEL3_READY == cstate)
1682 if (MESH_TUNNEL3_KEY_OK == t->estate)
1684 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered send queued data\n");
1685 send_queued_data (t);
1687 else if (MESH_TUNNEL3_KEY_UNINITIALIZED == t->estate)
1689 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1690 rekey_tunnel (t, NULL);
1695 if (MESH_TUNNEL3_READY == cstate && 3 <= GMT_count_connections (t))
1697 GMP_stop_search (t->peer);
1702 * Change the tunnel encryption state.
1704 * @param t Tunnel whose encryption state to change.
1705 * @param state New encryption state.
1708 GMT_change_estate (struct MeshTunnel3* t, enum MeshTunnel3EState state)
1712 LOG (GNUNET_ERROR_TYPE_DEBUG,
1713 "Tunnel %s estate was %s\n",
1714 GMP_2s (t->peer), estate2s (t->estate));
1715 LOG (GNUNET_ERROR_TYPE_DEBUG,
1716 "Tunnel %s estate is now %s\n",
1717 GMP_2s (t->peer), estate2s (state));
1718 if (myid != GMP_get_short_id (t->peer) &&
1719 MESH_TUNNEL3_KEY_OK != t->estate && MESH_TUNNEL3_KEY_OK == state)
1722 send_queued_data (t);
1730 * Add a connection to a tunnel.
1733 * @param c Connection.
1736 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1738 struct MeshTConnection *aux;
1740 GNUNET_assert (NULL != c);
1742 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1746 aux = GNUNET_new (struct MeshTConnection);
1748 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1753 * Remove a connection from a tunnel.
1756 * @param c Connection.
1759 GMT_remove_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1761 struct MeshTConnection *aux;
1762 struct MeshTConnection *next;
1764 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing connection %s from tunnel %s\n",
1765 GMC_2s (c), GMT_2s (t));
1766 for (aux = t->connection_head; aux != NULL; aux = next)
1771 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1776 /* Start new connections if needed */
1777 if (NULL == t->connection_head && GNUNET_NO == t->destroy)
1779 LOG (GNUNET_ERROR_TYPE_DEBUG, " no more connections\n");
1780 GMP_connect (t->peer);
1781 t->cstate = MESH_TUNNEL3_SEARCHING;
1785 /* If not marked as ready, no change is needed */
1786 if (MESH_TUNNEL3_READY != t->cstate)
1789 /* Check if any connection is ready to maintaing cstate */
1790 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1791 if (MESH_CONNECTION_READY == GMC_get_state (aux->c))
1794 t->cstate = MESH_TUNNEL3_WAITING;
1799 * Add a channel to a tunnel.
1802 * @param ch Channel.
1805 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1807 struct MeshTChannel *aux;
1809 GNUNET_assert (NULL != ch);
1811 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1813 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1815 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1820 aux = GNUNET_new (struct MeshTChannel);
1822 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1823 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1825 if (GNUNET_YES == t->destroy)
1827 t->destroy = GNUNET_NO;
1828 LOG (GNUNET_ERROR_TYPE_DEBUG, " undo destroy!\n");
1834 * Remove a channel from a tunnel.
1837 * @param ch Channel.
1840 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1842 struct MeshTChannel *aux;
1844 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1845 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1849 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1850 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1859 * Search for a channel by global ID.
1861 * @param t Tunnel containing the channel.
1862 * @param chid Public channel number.
1864 * @return channel handler, NULL if doesn't exist
1866 struct MeshChannel *
1867 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1869 struct MeshTChannel *iter;
1874 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1876 if (GMCH_get_id (iter->ch) == chid)
1880 return NULL == iter ? NULL : iter->ch;
1885 * Tunnel is empty: destroy it.
1887 * Notifies all connections about the destruction.
1889 * @param t Tunnel to destroy.
1892 GMT_destroy_empty (struct MeshTunnel3 *t)
1894 struct MeshTConnection *iter;
1896 LOG (GNUNET_ERROR_TYPE_DEBUG, "Tunnel empty: destroying scheduled\n");
1897 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1899 GMC_send_destroy (iter->c);
1902 t->cstate = MESH_TUNNEL3_NEW;
1903 t->destroy = GNUNET_YES;
1908 * Destroy tunnel if empty (no more channels).
1910 * @param t Tunnel to destroy if empty.
1913 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1915 if (1 < GMT_count_channels (t))
1918 GMT_destroy_empty (t);
1923 * Destroy the tunnel.
1925 * This function does not generate any warning traffic to clients or peers.
1928 * Cancel messages belonging to this tunnel queued to neighbors.
1929 * Free any allocated resources linked to the tunnel.
1931 * @param t The tunnel to destroy.
1934 GMT_destroy (struct MeshTunnel3 *t)
1936 struct MeshTConnection *iter_c;
1937 struct MeshTConnection *next_c;
1938 struct MeshTChannel *iter_ch;
1939 struct MeshTChannel *next_ch;
1946 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
1948 GNUNET_break (GNUNET_YES ==
1949 GNUNET_CONTAINER_multipeermap_remove (tunnels,
1950 GMP_get_id (t->peer), t));
1952 for (iter_c = t->connection_head; NULL != iter_c; iter_c = next_c)
1954 next_c = iter_c->next;
1955 GMC_destroy (iter_c->c);
1957 for (iter_ch = t->channel_head; NULL != iter_ch; iter_ch = next_ch)
1959 next_ch = iter_ch->next;
1960 GMCH_destroy (iter_ch->ch);
1961 /* Should only happen on shutdown, but it's ok. */
1964 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
1965 GMP_set_tunnel (t->peer, NULL);
1967 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1968 GNUNET_SCHEDULER_cancel (t->rekey_task);
1975 * @brief Use the given path for the tunnel.
1976 * Update the next and prev hops (and RCs).
1977 * (Re)start the path refresh in case the tunnel is locally owned.
1979 * @param t Tunnel to update.
1980 * @param p Path to use.
1982 * @return Connection created.
1984 struct MeshConnection *
1985 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
1987 struct MeshConnection *c;
1988 struct GNUNET_HashCode cid;
1989 unsigned int own_pos;
1991 if (NULL == t || NULL == p)
1997 for (own_pos = 0; own_pos < p->length; own_pos++)
1999 if (p->peers[own_pos] == myid)
2002 if (own_pos > p->length - 1)
2004 GNUNET_break_op (0);
2008 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
2009 c = GMC_new (&cid, t, p, own_pos);
2012 /* Path was flawed */
2015 GMT_add_connection (t, c);
2021 * Count established (ready) connections of a tunnel.
2023 * @param t Tunnel on which to count.
2025 * @return Number of connections.
2028 GMT_count_connections (struct MeshTunnel3 *t)
2030 struct MeshTConnection *iter;
2033 for (count = 0, iter = t->connection_head;
2035 iter = iter->next, count++);
2041 * Count channels of a tunnel.
2043 * @param t Tunnel on which to count.
2045 * @return Number of channels.
2048 GMT_count_channels (struct MeshTunnel3 *t)
2050 struct MeshTChannel *iter;
2053 for (count = 0, iter = t->channel_head;
2055 iter = iter->next, count++) /* skip */;
2062 * Get the connectivity state of a tunnel.
2066 * @return Tunnel's connectivity state.
2068 enum MeshTunnel3CState
2069 GMT_get_cstate (struct MeshTunnel3 *t)
2074 return (enum MeshTunnel3CState) -1;
2081 * Get the maximum buffer space for a tunnel towards a local client.
2085 * @return Biggest buffer space offered by any channel in the tunnel.
2088 GMT_get_channels_buffer (struct MeshTunnel3 *t)
2090 struct MeshTChannel *iter;
2091 unsigned int buffer;
2092 unsigned int ch_buf;
2094 if (NULL == t->channel_head)
2096 /* Probably getting buffer for a channel create/handshake. */
2101 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2103 ch_buf = get_channel_buffer (iter);
2104 if (ch_buf > buffer)
2112 * Get the total buffer space for a tunnel for P2P traffic.
2116 * @return Buffer space offered by all connections in the tunnel.
2119 GMT_get_connections_buffer (struct MeshTunnel3 *t)
2121 struct MeshTConnection *iter;
2122 unsigned int buffer;
2125 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2127 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
2131 buffer += get_connection_buffer (iter);
2139 * Get the tunnel's destination.
2143 * @return ID of the destination peer.
2145 const struct GNUNET_PeerIdentity *
2146 GMT_get_destination (struct MeshTunnel3 *t)
2148 return GMP_get_id (t->peer);
2153 * Get the tunnel's next free global channel ID.
2157 * @return GID of a channel free to use.
2160 GMT_get_next_chid (struct MeshTunnel3 *t)
2162 MESH_ChannelNumber chid;
2163 MESH_ChannelNumber mask;
2166 /* Set bit 30 depending on the ID relationship. Bit 31 is always 0 for GID.
2167 * If our ID is bigger or loopback tunnel, start at 0, bit 30 = 0
2168 * If peer's ID is bigger, start at 0x4... bit 30 = 1
2170 result = GNUNET_CRYPTO_cmp_peer_identity (&my_full_id, GMP_get_id (t->peer));
2176 while (NULL != GMT_get_channel (t, t->next_chid))
2178 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
2179 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2180 t->next_chid |= mask;
2182 chid = t->next_chid;
2183 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2184 t->next_chid |= mask;
2191 * Send ACK on one or more channels due to buffer in connections.
2193 * @param t Channel which has some free buffer space.
2196 GMT_unchoke_channels (struct MeshTunnel3 *t)
2198 struct MeshTChannel *iter;
2199 unsigned int buffer;
2200 unsigned int channels = GMT_count_channels (t);
2201 unsigned int choked_n;
2202 struct MeshChannel *choked[channels];
2204 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
2205 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
2206 if (NULL != t->channel_head)
2207 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
2209 /* Get buffer space */
2210 buffer = GMT_get_connections_buffer (t);
2216 /* Count and remember choked channels */
2218 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2220 if (GNUNET_NO == get_channel_allowed (iter))
2222 choked[choked_n++] = iter->ch;
2226 /* Unchoke random channels */
2227 while (0 < buffer && 0 < choked_n)
2229 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2231 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
2234 choked[r] = choked[choked_n];
2240 * Send ACK on one or more connections due to buffer space to the client.
2242 * Iterates all connections of the tunnel and sends ACKs appropriately.
2247 GMT_send_connection_acks (struct MeshTunnel3 *t)
2249 struct MeshTConnection *iter;
2252 uint32_t allow_per_connection;
2254 unsigned int buffer;
2256 LOG (GNUNET_ERROR_TYPE_DEBUG,
2257 "Tunnel send connection ACKs on %s\n",
2266 buffer = GMT_get_channels_buffer (t);
2268 /* Count connections, how many messages are already allowed */
2269 cs = GMT_count_connections (t);
2270 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
2272 allowed += get_connection_allowed (iter);
2275 /* Make sure there is no overflow */
2276 if (allowed > buffer)
2281 /* Authorize connections to send more data */
2282 to_allow = buffer; /* - allowed; */
2284 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
2286 allow_per_connection = to_allow/cs;
2287 to_allow -= allow_per_connection;
2289 if (get_connection_allowed (iter) > 64 / 3)
2293 GMC_allow (iter->c, buffer, GMC_is_origin (iter->c, GNUNET_YES));
2296 GNUNET_break (to_allow == 0);
2301 * Cancel a previously sent message while it's in the queue.
2303 * ONLY can be called before the continuation given to the send function
2304 * is called. Once the continuation is called, the message is no longer in the
2307 * @param q Handle to the queue.
2310 GMT_cancel (struct MeshTunnel3Queue *q)
2315 /* message_sent() will be called and free q */
2317 else if (NULL != q->tqd)
2319 unqueue_data (q->tqd);
2329 * Sends an already built message on a tunnel, encrypting it and
2330 * choosing the best connection.
2332 * @param message Message to send. Function modifies it.
2333 * @param t Tunnel on which this message is transmitted.
2334 * @param force Force the tunnel to take the message (buffer overfill).
2335 * @param cont Continuation to call once message is really sent.
2336 * @param cont_cls Closure for @c cont.
2338 * @return Handle to cancel message. NULL if @c cont is NULL.
2340 struct MeshTunnel3Queue *
2341 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2342 struct MeshTunnel3 *t, int force,
2343 GMT_sent cont, void *cont_cls)
2345 return send_prebuilt_message (message, t, force, cont, cont_cls, NULL);
2350 * Is the tunnel directed towards the local peer?
2354 * @return #GNUNET_YES if it is loopback.
2357 GMT_is_loopback (const struct MeshTunnel3 *t)
2359 return (myid == GMP_get_short_id (t->peer));
2364 * Is the tunnel this path already?
2369 * @return #GNUNET_YES a connection uses this path.
2372 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2374 struct MeshTConnection *iter;
2376 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2377 if (GMC_get_path (iter->c) == p)
2385 * Get a cost of a path for a tunnel considering existing connections.
2388 * @param path Candidate path.
2390 * @return Cost of the path (path length + number of overlapping nodes)
2393 GMT_get_path_cost (const struct MeshTunnel3 *t,
2394 const struct MeshPeerPath *path)
2396 struct MeshTConnection *iter;
2397 const struct MeshPeerPath *aux;
2398 unsigned int overlap;
2406 GNUNET_assert (NULL != t);
2408 for (i = 0; i < path->length; i++)
2410 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2412 aux = GMC_get_path (iter->c);
2416 for (j = 0; j < aux->length; j++)
2418 if (path->peers[i] == aux->peers[j])
2426 return (path->length + overlap) * (path->score * -1);
2431 * Get the static string for the peer this tunnel is directed.
2435 * @return Static string the destination peer's ID.
2438 GMT_2s (const struct MeshTunnel3 *t)
2443 return GMP_2s (t->peer);