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",
548 GNUNET_CRYPTO_symmetric_derive_iv (&siv, key, &iv, sizeof (uint32_t), NULL);
549 return GNUNET_CRYPTO_symmetric_decrypt (src, size, key, &siv, dst);
554 * Create key material by doing ECDH on the local and remote ephemeral keys.
556 * @param key_material Where to store the key material.
557 * @param ephemeral_key Peer's public ephemeral key.
560 derive_key_material (struct GNUNET_HashCode *key_material,
561 const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key)
564 GNUNET_CRYPTO_ecc_ecdh (my_ephemeral_key,
573 * Create a symmetic key from the identities of both ends and the key material
576 * @param key Destination for the generated key.
577 * @param sender ID of the peer that will encrypt with @c key.
578 * @param receiver ID of the peer that will decrypt with @c key.
579 * @param key_material Hash created with ECDH with the ephemeral keys.
582 derive_symmertic (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
583 const struct GNUNET_PeerIdentity *sender,
584 const struct GNUNET_PeerIdentity *receiver,
585 const struct GNUNET_HashCode *key_material)
587 const char salt[] = "MESH kx salt";
589 GNUNET_CRYPTO_kdf (key, sizeof (struct GNUNET_CRYPTO_SymmetricSessionKey),
591 key_material, sizeof (struct GNUNET_HashCode),
592 sender, sizeof (struct GNUNET_PeerIdentity),
593 receiver, sizeof (struct GNUNET_PeerIdentity),
598 * Pick a connection on which send the next data message.
600 * @param t Tunnel on which to send the message.
602 * @return The connection on which to send the next message.
604 static struct MeshConnection *
605 tunnel_get_connection (struct MeshTunnel3 *t)
607 struct MeshTConnection *iter;
608 struct MeshConnection *best;
610 unsigned int lowest_q;
612 LOG (GNUNET_ERROR_TYPE_DEBUG, "tunnel_get_connection %s\n", GMP_2s (t->peer));
615 for (iter = t->connection_head; NULL != iter; iter = iter->next)
617 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s: %u\n",
618 GMC_2s (iter->c), GMC_get_state (iter->c));
619 if (MESH_CONNECTION_READY == GMC_get_state (iter->c))
621 qn = GMC_get_qn (iter->c, GMC_is_origin (iter->c, GNUNET_YES));
622 LOG (GNUNET_ERROR_TYPE_DEBUG, " q_n %u, \n", qn);
630 LOG (GNUNET_ERROR_TYPE_DEBUG, " selected: connection %s\n", GMC_2s (best));
636 * Callback called when a queued message is sent.
638 * Calculates the average time and connection packet tracking.
640 * @param cls Closure (TunnelQueue handle).
641 * @param c Connection this message was on.
642 * @param q Connection queue handle (unused).
643 * @param type Type of message sent.
644 * @param fwd Was this a FWD going message?
645 * @param size Size of the message.
648 message_sent (void *cls,
649 struct MeshConnection *c,
650 struct MeshConnectionQueue *q,
651 uint16_t type, int fwd, size_t size)
653 struct MeshTunnel3Queue *qt = cls;
655 GNUNET_assert (NULL != qt->cont);
656 qt->cont (qt->cont_cls, GMC_get_tunnel (c), qt, type, size);
662 * Delete a queued message: either was sent or the channel was destroyed
663 * before the tunnel's key exchange had a chance to finish.
665 * @param tqd Delayed queue handle.
668 unqueue_data (struct MeshTunnelDelayed *tqd)
670 GNUNET_CONTAINER_DLL_remove (tqd->t->tq_head, tqd->t->tq_tail, tqd);
676 * Cache a message to be sent once tunnel is online.
678 * @param t Tunnel to hold the message.
679 * @param msg Message itself (copy will be made).
681 static struct MeshTunnelDelayed *
682 queue_data (struct MeshTunnel3 *t, const struct GNUNET_MessageHeader *msg)
684 struct MeshTunnelDelayed *tqd;
685 uint16_t size = ntohs (msg->size);
687 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue data on Tunnel %s\n", GMT_2s (t));
689 if (GNUNET_YES == is_ready (t))
695 tqd = GNUNET_malloc (sizeof (struct MeshTunnelDelayed) + size);
698 memcpy (&tqd[1], msg, size);
699 GNUNET_CONTAINER_DLL_insert_tail (t->tq_head, t->tq_tail, tqd);
706 * Sends an already built message on a tunnel, encrypting it and
707 * choosing the best connection.
709 * @param message Message to send. Function modifies it.
710 * @param t Tunnel on which this message is transmitted.
711 * @param force Force the tunnel to take the message (buffer overfill).
712 * @param cont Continuation to call once message is really sent.
713 * @param cont_cls Closure for @c cont.
714 * @param existing_q In case this a transmission of previously queued data,
715 * this should be TunnelQueue given to the client.
718 * @return Handle to cancel message. NULL if @c cont is NULL.
720 static struct MeshTunnel3Queue *
721 send_prebuilt_message (const struct GNUNET_MessageHeader *message,
722 struct MeshTunnel3 *t, int force,
723 GMT_sent cont, void *cont_cls,
724 struct MeshTunnel3Queue *existing_q)
726 struct MeshTunnel3Queue *tq;
727 struct MeshConnection *c;
728 struct GNUNET_MESH_Encrypted *msg;
729 size_t size = ntohs (message->size);
730 char cbuf[sizeof (struct GNUNET_MESH_Encrypted) + size];
735 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT Send on Tunnel %s\n", GMT_2s (t));
737 if (GNUNET_NO == is_ready (t))
739 struct MeshTunnelDelayed *tqd;
740 /* A non null existing_q indicates sending of queued data.
741 * Should only happen after tunnel becomes ready.
743 GNUNET_assert (NULL == existing_q);
744 tqd = queue_data (t, message);
747 tq = GNUNET_new (struct MeshTunnel3Queue);
751 tq->cont_cls = cont_cls;
755 GNUNET_assert (GNUNET_NO == GMT_is_loopback (t));
757 iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
758 msg = (struct GNUNET_MESH_Encrypted *) cbuf;
759 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED);
761 GNUNET_assert (t_encrypt (t, &msg[1], message, size, iv) == size);
762 msg->header.size = htons (sizeof (struct GNUNET_MESH_Encrypted) + size);
763 c = tunnel_get_connection (t);
766 if (GNUNET_YES == t->destroy || MESH_TUNNEL3_SEARCHING != t->cstate)
773 type = ntohs (message->type);
776 case GNUNET_MESSAGE_TYPE_MESH_DATA:
777 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
778 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
779 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
780 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
781 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
782 msg->cid = *GMC_get_id (c);
783 msg->ttl = htonl (default_ttl);
786 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
791 fwd = GMC_is_origin (c, GNUNET_YES);
795 (void) GMC_send_prebuilt_message (&msg->header, c, fwd, force, NULL, NULL);
798 if (NULL == existing_q)
800 tq = GNUNET_new (struct MeshTunnel3Queue); /* FIXME valgrind: leak*/
807 tq->cq = GMC_send_prebuilt_message (&msg->header, c, fwd, force,
810 tq->cont_cls = cont_cls;
817 * Send all cached messages that we can, tunnel is online.
819 * @param t Tunnel that holds the messages. Cannot be loopback.
822 send_queued_data (struct MeshTunnel3 *t)
824 struct MeshTunnelDelayed *tqd;
825 struct MeshTunnelDelayed *next;
828 LOG (GNUNET_ERROR_TYPE_DEBUG,
829 "GMT_send_queued_data on tunnel %s\n",
832 if (GMT_is_loopback (t))
838 if (GNUNET_NO == is_ready (t))
840 LOG (GNUNET_ERROR_TYPE_DEBUG, " not ready yet: %s/%s\n",
841 estate2s (t->estate), cstate2s (t->cstate));
845 room = GMT_get_connections_buffer (t);
846 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space: %u\n", room);
847 LOG (GNUNET_ERROR_TYPE_DEBUG, " tq head: %p\n", t->tq_head);
848 for (tqd = t->tq_head; NULL != tqd && room > 0; tqd = next)
850 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending queued data\n");
853 send_prebuilt_message ((struct GNUNET_MessageHeader *) &tqd[1],
855 NULL != tqd->tq ? tqd->tq->cont : NULL,
856 NULL != tqd->tq ? tqd->tq->cont_cls : NULL,
860 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_send_queued_data end\n", GMP_2s (t->peer));
865 * Sends key exchange message on a tunnel, choosing the best connection.
866 * Should not be called on loopback tunnels.
868 * @param t Tunnel on which this message is transmitted.
869 * @param message Message to send. Function modifies it.
872 send_kx (struct MeshTunnel3 *t,
873 const struct GNUNET_MessageHeader *message)
875 struct MeshConnection *c;
876 struct GNUNET_MESH_KX *msg;
877 size_t size = ntohs (message->size);
878 char cbuf[sizeof (struct GNUNET_MESH_KX) + size];
882 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT KX on Tunnel %s\n", GMT_2s (t));
884 /* Avoid loopback. */
885 if (GMT_is_loopback (t))
887 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback!\n");
892 /* Must have a connection. */
893 if (NULL == t->connection_head)
895 GNUNET_break (MESH_TUNNEL3_SEARCHING == t->cstate);
900 msg = (struct GNUNET_MESH_KX *) cbuf;
901 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX);
902 msg->header.size = htons (sizeof (struct GNUNET_MESH_KX) + size);
903 c = tunnel_get_connection (t);
906 GNUNET_break (GNUNET_YES == t->destroy || MESH_TUNNEL3_READY != t->cstate);
910 type = ntohs (message->type);
913 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
914 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
915 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
916 msg->reserved = htonl (0);
917 memcpy (&msg[1], message, size);
920 LOG (GNUNET_ERROR_TYPE_DEBUG, "unkown type %s\n",
925 fwd = GMC_is_origin (t->connection_head->c, GNUNET_YES);
926 /* TODO save handle and cancel in case of a unneeded retransmission */
927 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
932 * Send the ephemeral key on a tunnel.
934 * @param t Tunnel on which to send the key.
937 send_ephemeral (struct MeshTunnel3 *t)
939 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
941 kx_msg.sender_status = htonl (t->estate);
942 send_kx (t, &kx_msg.header);
946 * Send a ping message on a tunnel.
948 * @param t Tunnel on which to send the ping.
951 send_ping (struct MeshTunnel3 *t)
953 struct GNUNET_MESH_KX_Ping msg;
955 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
956 msg.header.size = htons (sizeof (msg));
957 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PING);
958 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
959 msg.target = *GMP_get_id (t->peer);
960 msg.nonce = t->kx_ctx->challenge;
962 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
963 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&msg.target));
964 t_encrypt (t, &msg.target, &msg.target, ping_encryption_size(), msg.iv);
965 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
966 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg.target));
968 send_kx (t, &msg.header);
973 * Send a pong message on a tunnel.
975 * @param t Tunnel on which to send the pong.
976 * @param challenge Value sent in the ping that we have to send back.
979 send_pong (struct MeshTunnel3 *t, uint32_t challenge)
981 struct GNUNET_MESH_KX_Pong msg;
983 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s()\n", __FUNCTION__);
984 msg.header.size = htons (sizeof (msg));
985 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_PONG);
986 msg.iv = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
987 msg.nonce = challenge;
988 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending %u\n", msg.nonce);
989 t_encrypt (t, &msg.nonce, &msg.nonce, sizeof (msg.nonce), msg.iv);
990 LOG (GNUNET_ERROR_TYPE_DEBUG, " e sending %u\n", msg.nonce);
992 send_kx (t, &msg.header);
997 * Initiate a rekey with the remote peer.
999 * @param cls Closure (tunnel).
1000 * @param tc TaskContext.
1003 rekey_tunnel (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1005 struct MeshTunnel3 *t = cls;
1007 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1009 LOG (GNUNET_ERROR_TYPE_DEBUG, "Re-key Tunnel %s\n", GMT_2s (t));
1010 if (NULL != tc && 0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
1013 if (NULL == t->kx_ctx)
1015 LOG (GNUNET_ERROR_TYPE_DEBUG, " new kx ctx\n");
1016 t->kx_ctx = GNUNET_new (struct MeshTunnelKXCtx);
1017 t->kx_ctx->challenge =
1018 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
1019 t->kx_ctx->d_key_old = t->d_key;
1020 LOG (GNUNET_ERROR_TYPE_DEBUG, " new challenge for %s: %u\n",
1021 GMT_2s (t), t->kx_ctx->challenge);
1026 case MESH_TUNNEL3_KEY_UNINITIALIZED:
1027 t->estate = MESH_TUNNEL3_KEY_SENT;
1029 case MESH_TUNNEL3_KEY_SENT:
1031 case MESH_TUNNEL3_KEY_PING:
1032 case MESH_TUNNEL3_KEY_OK:
1034 t->estate = MESH_TUNNEL3_KEY_PING;
1037 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unexpected state %u\n", t->estate);
1040 LOG (GNUNET_ERROR_TYPE_DEBUG, " next call in %s\n",
1041 GNUNET_STRINGS_relative_time_to_string (REKEY_WAIT, GNUNET_YES));
1042 t->rekey_task = GNUNET_SCHEDULER_add_delayed (REKEY_WAIT, &rekey_tunnel, t);
1047 * Out ephemeral key has changed, create new session key on all tunnels.
1049 * @param cls Closure (size of the hashmap).
1050 * @param key Current public key.
1051 * @param value Value in the hash map (tunnel).
1053 * @return #GNUNET_YES, so we should continue to iterate,
1056 rekey_iterator (void *cls,
1057 const struct GNUNET_PeerIdentity *key,
1060 struct MeshTunnel3 *t = value;
1061 struct GNUNET_TIME_Relative delay;
1062 long n = (long) cls;
1065 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1068 r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) n * 100);
1069 delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, r);
1070 t->rekey_task = GNUNET_SCHEDULER_add_delayed (delay, &rekey_tunnel, t);
1077 * Create a new ephemeral key and key message, schedule next rekeying.
1079 * @param cls Closure (unused).
1080 * @param tc TaskContext.
1083 rekey (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1085 struct GNUNET_TIME_Absolute time;
1088 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1090 if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
1093 GNUNET_free_non_null (my_ephemeral_key);
1094 my_ephemeral_key = GNUNET_CRYPTO_ecdhe_key_create ();
1096 time = GNUNET_TIME_absolute_get ();
1097 kx_msg.creation_time = GNUNET_TIME_absolute_hton (time);
1098 time = GNUNET_TIME_absolute_add (time, rekey_period);
1099 time = GNUNET_TIME_absolute_add (time, GNUNET_TIME_UNIT_MINUTES);
1100 kx_msg.expiration_time = GNUNET_TIME_absolute_hton (time);
1101 GNUNET_CRYPTO_ecdhe_key_get_public (my_ephemeral_key, &kx_msg.ephemeral_key);
1103 GNUNET_assert (GNUNET_OK ==
1104 GNUNET_CRYPTO_eddsa_sign (my_private_key,
1106 &kx_msg.signature));
1108 n = (long) GNUNET_CONTAINER_multipeermap_size (tunnels);
1109 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &rekey_iterator, (void *) n);
1111 rekey_task = GNUNET_SCHEDULER_add_delayed (rekey_period, &rekey, NULL);
1116 * Called only on shutdown, destroy every tunnel.
1118 * @param cls Closure (unused).
1119 * @param key Current public key.
1120 * @param value Value in the hash map (tunnel).
1122 * @return #GNUNET_YES, so we should continue to iterate,
1125 destroy_iterator (void *cls,
1126 const struct GNUNET_PeerIdentity *key,
1129 struct MeshTunnel3 *t = value;
1137 * Notify remote peer that we don't know a channel he is talking about,
1138 * probably CHANNEL_DESTROY was missed.
1140 * @param t Tunnel on which to notify.
1141 * @param gid ID of the channel.
1144 send_channel_destroy (struct MeshTunnel3 *t, unsigned int gid)
1146 struct GNUNET_MESH_ChannelManage msg;
1148 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY);
1149 msg.header.size = htons (sizeof (msg));
1150 msg.chid = htonl (gid);
1152 LOG (GNUNET_ERROR_TYPE_DEBUG,
1153 "WARNING destroying unknown channel %u on tunnel %s\n",
1155 send_prebuilt_message (&msg.header, t, GNUNET_YES, NULL, NULL, NULL);
1160 * Demultiplex data per channel and call appropriate channel handler.
1162 * @param t Tunnel on which the data came.
1163 * @param msg Data message.
1164 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1165 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1166 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1167 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1170 handle_data (struct MeshTunnel3 *t,
1171 const struct GNUNET_MESH_Data *msg,
1174 struct MeshChannel *ch;
1178 size = ntohs (msg->header.size);
1180 sizeof (struct GNUNET_MESH_Data) +
1181 sizeof (struct GNUNET_MessageHeader))
1186 LOG (GNUNET_ERROR_TYPE_DEBUG, " payload of type %s\n",
1187 GM_m2s (ntohs (msg[1].header.type)));
1190 ch = GMT_get_channel (t, ntohl (msg->chid));
1193 GNUNET_STATISTICS_update (stats, "# data on unknown channel",
1195 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel 0x%X unknown\n",
1197 send_channel_destroy (t, ntohl (msg->chid));
1201 GMCH_handle_data (ch, msg, fwd);
1206 * Demultiplex data ACKs per channel and update appropriate channel buffer info.
1208 * @param t Tunnel on which the DATA ACK came.
1209 * @param msg DATA ACK message.
1210 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1211 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1212 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1213 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1216 handle_data_ack (struct MeshTunnel3 *t,
1217 const struct GNUNET_MESH_DataACK *msg,
1220 struct MeshChannel *ch;
1224 size = ntohs (msg->header.size);
1225 if (size != sizeof (struct GNUNET_MESH_DataACK))
1232 ch = GMT_get_channel (t, ntohl (msg->chid));
1235 GNUNET_STATISTICS_update (stats, "# data ack on unknown channel",
1237 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1242 GMCH_handle_data_ack (ch, msg, fwd);
1247 * Handle channel create.
1249 * @param t Tunnel on which the data came.
1250 * @param msg Data message.
1253 handle_ch_create (struct MeshTunnel3 *t,
1254 const struct GNUNET_MESH_ChannelCreate *msg)
1256 struct MeshChannel *ch;
1260 size = ntohs (msg->header.size);
1261 if (size != sizeof (struct GNUNET_MESH_ChannelCreate))
1268 ch = GMT_get_channel (t, ntohl (msg->chid));
1269 if (NULL != ch && ! GMT_is_loopback (t))
1271 /* Probably a retransmission, safe to ignore */
1272 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists...\n");
1276 ch = GMCH_handle_create (t, msg);
1279 GMT_add_channel (t, ch);
1285 * Handle channel NACK: check correctness and call channel handler for NACKs.
1287 * @param t Tunnel on which the NACK came.
1288 * @param msg NACK message.
1291 handle_ch_nack (struct MeshTunnel3 *t,
1292 const struct GNUNET_MESH_ChannelManage *msg)
1294 struct MeshChannel *ch;
1298 size = ntohs (msg->header.size);
1299 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1306 ch = GMT_get_channel (t, ntohl (msg->chid));
1309 GNUNET_STATISTICS_update (stats, "# channel NACK on unknown channel",
1311 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1316 GMCH_handle_nack (ch);
1321 * Handle a CHANNEL ACK (SYNACK/ACK).
1323 * @param t Tunnel on which the CHANNEL ACK came.
1324 * @param msg CHANNEL ACK message.
1325 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1326 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1327 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1328 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1331 handle_ch_ack (struct MeshTunnel3 *t,
1332 const struct GNUNET_MESH_ChannelManage *msg,
1335 struct MeshChannel *ch;
1339 size = ntohs (msg->header.size);
1340 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1347 ch = GMT_get_channel (t, ntohl (msg->chid));
1350 GNUNET_STATISTICS_update (stats, "# channel ack on unknown channel",
1352 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING channel %u unknown\n",
1357 GMCH_handle_ack (ch, msg, fwd);
1363 * Handle a channel destruction message.
1365 * @param t Tunnel on which the message came.
1366 * @param msg Channel destroy message.
1367 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1368 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1369 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1370 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1373 handle_ch_destroy (struct MeshTunnel3 *t,
1374 const struct GNUNET_MESH_ChannelManage *msg,
1377 struct MeshChannel *ch;
1381 size = ntohs (msg->header.size);
1382 if (size != sizeof (struct GNUNET_MESH_ChannelManage))
1389 ch = GMT_get_channel (t, ntohl (msg->chid));
1392 /* Probably a retransmission, safe to ignore */
1396 GMCH_handle_destroy (ch, msg, fwd);
1401 * The peer's ephemeral key has changed: update the symmetrical keys.
1403 * @param t Tunnel this message came on.
1404 * @param msg Key eXchange message.
1407 handle_ephemeral (struct MeshTunnel3 *t,
1408 const struct GNUNET_MESH_KX_Ephemeral *msg)
1410 struct GNUNET_HashCode km;
1411 LOG (GNUNET_ERROR_TYPE_DEBUG, " ephemeral key message\n");
1413 if (GNUNET_OK != check_ephemeral (t, msg))
1415 GNUNET_break_op (0);
1418 derive_key_material (&km, &msg->ephemeral_key);
1419 LOG (GNUNET_ERROR_TYPE_DEBUG, " km is %s\n", GNUNET_h2s (&km));
1420 derive_symmertic (&t->e_key, &my_full_id, GMP_get_id (t->peer), &km);
1421 derive_symmertic (&t->d_key, GMP_get_id (t->peer), &my_full_id, &km);
1422 if (MESH_TUNNEL3_KEY_SENT == t->estate)
1424 LOG (GNUNET_ERROR_TYPE_DEBUG, " our key was sent, send ping\n");
1426 t->estate = MESH_TUNNEL3_KEY_PING;
1432 * Peer wants to check our symmetrical keys by sending an encrypted challenge.
1433 * Answer with by retransmitting the challenge with the "opposite" key.
1435 * @param t Tunnel this message came on.
1436 * @param msg Key eXchange Ping message.
1439 handle_ping (struct MeshTunnel3 *t,
1440 const struct GNUNET_MESH_KX_Ping *msg)
1442 struct GNUNET_MESH_KX_Ping res;
1444 if (ntohs (msg->header.size) != sizeof (res))
1446 GNUNET_break_op (0);
1450 LOG (GNUNET_ERROR_TYPE_DEBUG, " ping message\n");
1451 t_decrypt (t, &res.target, &msg->target, ping_encryption_size (), msg->iv);
1452 if (0 != memcmp (&my_full_id, &res.target, sizeof (my_full_id)))
1454 GNUNET_STATISTICS_update (stats, "# malformed PINGs", 1, GNUNET_NO);
1455 LOG (GNUNET_ERROR_TYPE_DEBUG, " WARNING malformed PING\n");
1456 LOG (GNUNET_ERROR_TYPE_DEBUG, " e got %u\n", msg->nonce);
1457 LOG (GNUNET_ERROR_TYPE_DEBUG, " e towards %s\n", GNUNET_i2s (&msg->target));
1458 LOG (GNUNET_ERROR_TYPE_DEBUG, " got %u\n", res.nonce);
1459 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s\n", GNUNET_i2s (&res.target));
1463 send_pong (t, res.nonce);
1468 * Peer has answer to our challenge.
1469 * If answer is successful, consider the key exchange finished and clean
1470 * up all related state.
1472 * @param t Tunnel this message came on.
1473 * @param msg Key eXchange Pong message.
1476 handle_pong (struct MeshTunnel3 *t,
1477 const struct GNUNET_MESH_KX_Pong *msg)
1481 LOG (GNUNET_ERROR_TYPE_DEBUG, "PONG received\n");
1482 if (GNUNET_SCHEDULER_NO_TASK == t->rekey_task)
1484 GNUNET_STATISTICS_update (stats, "# duplicate PONG messages", 1, GNUNET_NO);
1487 t_decrypt (t, &challenge, &msg->nonce, sizeof (uint32_t), msg->iv);
1489 if (challenge != t->kx_ctx->challenge)
1491 LOG (GNUNET_ERROR_TYPE_DEBUG,
1492 "Wrong PONG challenge: %u (e: %u). Expected: %u.\n",
1493 challenge, msg->nonce, t->kx_ctx->challenge);
1494 GNUNET_break_op (0);
1497 GNUNET_SCHEDULER_cancel (t->rekey_task);
1498 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1499 GNUNET_free (t->kx_ctx);
1501 GMT_change_estate (t, MESH_TUNNEL3_KEY_OK);
1506 * Demultiplex by message type and call appropriate handler for a message
1507 * towards a channel of a local tunnel.
1509 * @param t Tunnel this message came on.
1510 * @param msgh Message header.
1511 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1512 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1513 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1514 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1517 handle_decrypted (struct MeshTunnel3 *t,
1518 const struct GNUNET_MessageHeader *msgh,
1523 type = ntohs (msgh->type);
1524 LOG (GNUNET_ERROR_TYPE_DEBUG,
1525 "Got a %s message!\n",
1530 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1531 /* Don't send hop ACK, wait for client to ACK */
1532 handle_data (t, (struct GNUNET_MESH_Data *) msgh, fwd);
1535 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1536 handle_data_ack (t, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1539 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1540 handle_ch_create (t,
1541 (struct GNUNET_MESH_ChannelCreate *) msgh);
1544 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1546 (struct GNUNET_MESH_ChannelManage *) msgh);
1549 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1551 (struct GNUNET_MESH_ChannelManage *) msgh,
1555 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1556 handle_ch_destroy (t,
1557 (struct GNUNET_MESH_ChannelManage *) msgh,
1562 GNUNET_break_op (0);
1563 LOG (GNUNET_ERROR_TYPE_DEBUG,
1564 "end-to-end message not known (%u)\n",
1565 ntohs (msgh->type));
1569 /******************************************************************************/
1570 /******************************** API ***********************************/
1571 /******************************************************************************/
1574 * Decrypt and demultiplex by message type. Call appropriate handler
1575 * for every message.
1577 * @param t Tunnel this message came on.
1578 * @param msg Encrypted message.
1581 GMT_handle_encrypted (struct MeshTunnel3 *t,
1582 const struct GNUNET_MESH_Encrypted *msg)
1584 size_t size = ntohs (msg->header.size);
1585 size_t payload_size = size - sizeof (struct GNUNET_MESH_Encrypted);
1586 size_t decrypted_size;
1587 char cbuf [payload_size];
1588 struct GNUNET_MessageHeader *msgh;
1591 decrypted_size = t_decrypt (t, cbuf, &msg[1], payload_size, msg->iv);
1593 while (off < decrypted_size)
1595 msgh = (struct GNUNET_MessageHeader *) &cbuf[off];
1596 handle_decrypted (t, msgh, GNUNET_SYSERR);
1597 off += ntohs (msgh->size);
1603 * Demultiplex an encapsulated KX message by message type.
1605 * @param t Tunnel on which the message came.
1606 * @param message Payload of KX message.
1609 GMT_handle_kx (struct MeshTunnel3 *t,
1610 const struct GNUNET_MessageHeader *message)
1614 type = ntohs (message->type);
1615 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message received\n", type);
1618 case GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL:
1619 handle_ephemeral (t, (struct GNUNET_MESH_KX_Ephemeral *) message);
1622 case GNUNET_MESSAGE_TYPE_MESH_KX_PING:
1623 handle_ping (t, (struct GNUNET_MESH_KX_Ping *) message);
1626 case GNUNET_MESSAGE_TYPE_MESH_KX_PONG:
1627 handle_pong (t, (struct GNUNET_MESH_KX_Pong *) message);
1631 GNUNET_break_op (0);
1632 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx message not known (%u)\n", type);
1638 * Initialize the tunnel subsystem.
1640 * @param c Configuration handle.
1641 * @param key ECC private key, to derive all other keys and do crypto.
1644 GMT_init (const struct GNUNET_CONFIGURATION_Handle *c,
1645 const struct GNUNET_CRYPTO_EddsaPrivateKey *key)
1647 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1649 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "DEFAULT_TTL",
1652 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
1653 "MESH", "DEFAULT_TTL", "USING DEFAULT");
1657 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REKEY_PERIOD",
1660 rekey_period = GNUNET_TIME_UNIT_DAYS;
1663 my_private_key = key;
1664 kx_msg.header.size = htons (sizeof (kx_msg));
1665 kx_msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KX_EPHEMERAL);
1666 kx_msg.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_MESH_KX);
1667 kx_msg.purpose.size = htonl (ephemeral_purpose_size ());
1668 kx_msg.origin_identity = my_full_id;
1669 rekey_task = GNUNET_SCHEDULER_add_now (&rekey, NULL);
1671 tunnels = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
1676 * Shut down the tunnel subsystem.
1681 if (GNUNET_SCHEDULER_NO_TASK != rekey_task)
1683 GNUNET_SCHEDULER_cancel (rekey_task);
1684 rekey_task = GNUNET_SCHEDULER_NO_TASK;
1686 GNUNET_CONTAINER_multipeermap_iterate (tunnels, &destroy_iterator, NULL);
1687 GNUNET_CONTAINER_multipeermap_destroy (tunnels);
1694 * @param destination Peer this tunnel is towards.
1696 struct MeshTunnel3 *
1697 GMT_new (struct MeshPeer *destination)
1699 struct MeshTunnel3 *t;
1701 t = GNUNET_new (struct MeshTunnel3);
1703 t->peer = destination;
1706 GNUNET_CONTAINER_multipeermap_put (tunnels, GMP_get_id (destination), t,
1707 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
1718 * Change the tunnel's connection state.
1720 * @param t Tunnel whose connection state to change.
1721 * @param cstate New connection state.
1724 GMT_change_cstate (struct MeshTunnel3* t, enum MeshTunnel3CState cstate)
1728 LOG (GNUNET_ERROR_TYPE_DEBUG,
1729 "Tunnel %s cstate was %s\n",
1730 GMP_2s (t->peer), cstate2s (t->cstate));
1731 LOG (GNUNET_ERROR_TYPE_DEBUG,
1732 "Tunnel %s cstate is now %s\n",
1733 GMP_2s (t->peer), cstate2s (cstate));
1734 if (myid != GMP_get_short_id (t->peer) &&
1735 MESH_TUNNEL3_READY != t->cstate &&
1736 MESH_TUNNEL3_READY == cstate)
1739 if (MESH_TUNNEL3_KEY_OK == t->estate)
1741 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered send queued data\n");
1742 send_queued_data (t);
1744 else if (MESH_TUNNEL3_KEY_UNINITIALIZED == t->estate)
1746 LOG (GNUNET_ERROR_TYPE_DEBUG, " triggered rekey\n");
1747 rekey_tunnel (t, NULL);
1752 if (MESH_TUNNEL3_READY == cstate && 3 <= GMT_count_connections (t))
1754 GMP_stop_search (t->peer);
1759 * Change the tunnel encryption state.
1761 * @param t Tunnel whose encryption state to change.
1762 * @param state New encryption state.
1765 GMT_change_estate (struct MeshTunnel3* t, enum MeshTunnel3EState state)
1769 LOG (GNUNET_ERROR_TYPE_DEBUG,
1770 "Tunnel %s estate was %s\n",
1771 GMP_2s (t->peer), estate2s (t->estate));
1772 LOG (GNUNET_ERROR_TYPE_DEBUG,
1773 "Tunnel %s estate is now %s\n",
1774 GMP_2s (t->peer), estate2s (state));
1775 if (myid != GMP_get_short_id (t->peer) &&
1776 MESH_TUNNEL3_KEY_OK != t->estate && MESH_TUNNEL3_KEY_OK == state)
1779 send_queued_data (t);
1787 * Add a connection to a tunnel.
1790 * @param c Connection.
1793 GMT_add_connection (struct MeshTunnel3 *t, struct MeshConnection *c)
1795 struct MeshTConnection *aux;
1797 GNUNET_assert (NULL != c);
1799 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1803 aux = GNUNET_new (struct MeshTConnection);
1805 GNUNET_CONTAINER_DLL_insert_tail (t->connection_head, t->connection_tail, aux);
1810 * Mark a path as no longer valid for this tunnel: has been tried and failed.
1812 * @param t Tunnel to update.
1813 * @param path Invalid path to remove. Is destroyed after removal.
1816 GMT_remove_path (struct MeshTunnel3 *t, struct MeshPeerPath *path)
1818 GMP_remove_path (t->peer, path);
1823 * Remove a connection from a tunnel.
1826 * @param c Connection.
1829 GMT_remove_connection (struct MeshTunnel3 *t,
1830 struct MeshConnection *c)
1832 struct MeshTConnection *aux;
1833 struct MeshTConnection *next;
1835 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing connection %s from tunnel %s\n",
1836 GMC_2s (c), GMT_2s (t));
1837 for (aux = t->connection_head; aux != NULL; aux = next)
1842 GNUNET_CONTAINER_DLL_remove (t->connection_head, t->connection_tail, aux);
1847 /* Start new connections if needed */
1848 if (NULL == t->connection_head
1849 && GNUNET_NO == t->destroy
1850 && GNUNET_NO == shutting_down)
1852 LOG (GNUNET_ERROR_TYPE_DEBUG, " no more connections, getting new ones\n");
1853 GMP_connect (t->peer);
1854 t->cstate = MESH_TUNNEL3_SEARCHING;
1858 /* If not marked as ready, no change is needed */
1859 if (MESH_TUNNEL3_READY != t->cstate)
1862 /* Check if any connection is ready to maintaing cstate */
1863 for (aux = t->connection_head; aux != NULL; aux = aux->next)
1864 if (MESH_CONNECTION_READY == GMC_get_state (aux->c))
1867 t->cstate = MESH_TUNNEL3_WAITING;
1872 * Add a channel to a tunnel.
1875 * @param ch Channel.
1878 GMT_add_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1880 struct MeshTChannel *aux;
1882 GNUNET_assert (NULL != ch);
1884 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding channel %p to tunnel %p\n", ch, t);
1886 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1888 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there %p\n", aux->ch);
1893 aux = GNUNET_new (struct MeshTChannel);
1895 LOG (GNUNET_ERROR_TYPE_DEBUG, " adding %p to %p\n", aux, t->channel_head);
1896 GNUNET_CONTAINER_DLL_insert_tail (t->channel_head, t->channel_tail, aux);
1898 if (GNUNET_YES == t->destroy)
1900 t->destroy = GNUNET_NO;
1901 LOG (GNUNET_ERROR_TYPE_DEBUG, " undo destroy!\n");
1907 * Remove a channel from a tunnel.
1910 * @param ch Channel.
1913 GMT_remove_channel (struct MeshTunnel3 *t, struct MeshChannel *ch)
1915 struct MeshTChannel *aux;
1917 LOG (GNUNET_ERROR_TYPE_DEBUG, "Removing channel %p from tunnel %p\n", ch, t);
1918 for (aux = t->channel_head; aux != NULL; aux = aux->next)
1922 LOG (GNUNET_ERROR_TYPE_DEBUG, " found! %s\n", GMCH_2s (ch));
1923 GNUNET_CONTAINER_DLL_remove (t->channel_head, t->channel_tail, aux);
1932 * Search for a channel by global ID.
1934 * @param t Tunnel containing the channel.
1935 * @param chid Public channel number.
1937 * @return channel handler, NULL if doesn't exist
1939 struct MeshChannel *
1940 GMT_get_channel (struct MeshTunnel3 *t, MESH_ChannelNumber chid)
1942 struct MeshTChannel *iter;
1947 for (iter = t->channel_head; NULL != iter; iter = iter->next)
1949 if (GMCH_get_id (iter->ch) == chid)
1953 return NULL == iter ? NULL : iter->ch;
1958 * Tunnel is empty: destroy it.
1960 * Notifies all connections about the destruction.
1962 * @param t Tunnel to destroy.
1965 GMT_destroy_empty (struct MeshTunnel3 *t)
1967 struct MeshTConnection *iter;
1969 LOG (GNUNET_ERROR_TYPE_DEBUG, "Tunnel %s empty: destroying scheduled\n",
1971 for (iter = t->connection_head; NULL != iter; iter = iter->next)
1973 GMC_send_destroy (iter->c);
1976 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
1978 t->estate = MESH_TUNNEL3_KEY_UNINITIALIZED;
1979 GNUNET_SCHEDULER_cancel (t->rekey_task);
1980 t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
1981 GNUNET_free (t->kx_ctx);
1984 t->cstate = MESH_TUNNEL3_NEW;
1985 t->destroy = GNUNET_YES;
1990 * Destroy tunnel if empty (no more channels).
1992 * @param t Tunnel to destroy if empty.
1995 GMT_destroy_if_empty (struct MeshTunnel3 *t)
1997 if (1 < GMT_count_channels (t))
2000 GMT_destroy_empty (t);
2005 * Destroy the tunnel.
2007 * This function does not generate any warning traffic to clients or peers.
2010 * Cancel messages belonging to this tunnel queued to neighbors.
2011 * Free any allocated resources linked to the tunnel.
2013 * @param t The tunnel to destroy.
2016 GMT_destroy (struct MeshTunnel3 *t)
2018 struct MeshTConnection *iter_c;
2019 struct MeshTConnection *next_c;
2020 struct MeshTChannel *iter_ch;
2021 struct MeshTChannel *next_ch;
2028 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying tunnel %s\n", GMP_2s (t->peer));
2030 GNUNET_break (GNUNET_YES ==
2031 GNUNET_CONTAINER_multipeermap_remove (tunnels,
2032 GMP_get_id (t->peer), t));
2034 for (iter_c = t->connection_head; NULL != iter_c; iter_c = next_c)
2036 next_c = iter_c->next;
2037 GMC_destroy (iter_c->c);
2039 for (iter_ch = t->channel_head; NULL != iter_ch; iter_ch = next_ch)
2041 next_ch = iter_ch->next;
2042 GMCH_destroy (iter_ch->ch);
2043 /* Should only happen on shutdown, but it's ok. */
2046 GNUNET_STATISTICS_update (stats, "# tunnels", -1, GNUNET_NO);
2047 GMP_set_tunnel (t->peer, NULL);
2049 if (GNUNET_SCHEDULER_NO_TASK != t->rekey_task)
2050 GNUNET_SCHEDULER_cancel (t->rekey_task);
2057 * @brief Use the given path for the tunnel.
2058 * Update the next and prev hops (and RCs).
2059 * (Re)start the path refresh in case the tunnel is locally owned.
2061 * @param t Tunnel to update.
2062 * @param p Path to use.
2064 * @return Connection created.
2066 struct MeshConnection *
2067 GMT_use_path (struct MeshTunnel3 *t, struct MeshPeerPath *p)
2069 struct MeshConnection *c;
2070 struct GNUNET_HashCode cid;
2071 unsigned int own_pos;
2073 if (NULL == t || NULL == p)
2079 for (own_pos = 0; own_pos < p->length; own_pos++)
2081 if (p->peers[own_pos] == myid)
2084 if (own_pos > p->length - 1)
2086 GNUNET_break_op (0);
2090 GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE, &cid);
2091 c = GMC_new (&cid, t, p, own_pos);
2094 /* Path was flawed */
2097 GMT_add_connection (t, c);
2103 * Count established (ready) connections of a tunnel.
2105 * @param t Tunnel on which to count.
2107 * @return Number of connections.
2110 GMT_count_connections (struct MeshTunnel3 *t)
2112 struct MeshTConnection *iter;
2115 for (count = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
2116 if (MESH_CONNECTION_DESTROYED != GMC_get_state (iter->c))
2123 * Count channels of a tunnel.
2125 * @param t Tunnel on which to count.
2127 * @return Number of channels.
2130 GMT_count_channels (struct MeshTunnel3 *t)
2132 struct MeshTChannel *iter;
2135 for (count = 0, iter = t->channel_head;
2137 iter = iter->next, count++) /* skip */;
2144 * Get the connectivity state of a tunnel.
2148 * @return Tunnel's connectivity state.
2150 enum MeshTunnel3CState
2151 GMT_get_cstate (struct MeshTunnel3 *t)
2156 return (enum MeshTunnel3CState) -1;
2163 * Get the maximum buffer space for a tunnel towards a local client.
2167 * @return Biggest buffer space offered by any channel in the tunnel.
2170 GMT_get_channels_buffer (struct MeshTunnel3 *t)
2172 struct MeshTChannel *iter;
2173 unsigned int buffer;
2174 unsigned int ch_buf;
2176 if (NULL == t->channel_head)
2178 /* Probably getting buffer for a channel create/handshake. */
2183 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2185 ch_buf = get_channel_buffer (iter);
2186 if (ch_buf > buffer)
2194 * Get the total buffer space for a tunnel for P2P traffic.
2198 * @return Buffer space offered by all connections in the tunnel.
2201 GMT_get_connections_buffer (struct MeshTunnel3 *t)
2203 struct MeshTConnection *iter;
2204 unsigned int buffer;
2207 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2209 if (GMC_get_state (iter->c) != MESH_CONNECTION_READY)
2213 buffer += get_connection_buffer (iter);
2221 * Get the tunnel's destination.
2225 * @return ID of the destination peer.
2227 const struct GNUNET_PeerIdentity *
2228 GMT_get_destination (struct MeshTunnel3 *t)
2230 return GMP_get_id (t->peer);
2235 * Get the tunnel's next free global channel ID.
2239 * @return GID of a channel free to use.
2242 GMT_get_next_chid (struct MeshTunnel3 *t)
2244 MESH_ChannelNumber chid;
2245 MESH_ChannelNumber mask;
2248 /* Set bit 30 depending on the ID relationship. Bit 31 is always 0 for GID.
2249 * If our ID is bigger or loopback tunnel, start at 0, bit 30 = 0
2250 * If peer's ID is bigger, start at 0x4... bit 30 = 1
2252 result = GNUNET_CRYPTO_cmp_peer_identity (&my_full_id, GMP_get_id (t->peer));
2258 while (NULL != GMT_get_channel (t, t->next_chid))
2260 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", t->next_chid);
2261 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2262 t->next_chid |= mask;
2264 chid = t->next_chid;
2265 t->next_chid = (t->next_chid + 1) & ~GNUNET_MESH_LOCAL_CHANNEL_ID_CLI;
2266 t->next_chid |= mask;
2273 * Send ACK on one or more channels due to buffer in connections.
2275 * @param t Channel which has some free buffer space.
2278 GMT_unchoke_channels (struct MeshTunnel3 *t)
2280 struct MeshTChannel *iter;
2281 unsigned int buffer;
2282 unsigned int channels = GMT_count_channels (t);
2283 unsigned int choked_n;
2284 struct MeshChannel *choked[channels];
2286 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMT_unchoke_channels on %s\n", GMT_2s (t));
2287 LOG (GNUNET_ERROR_TYPE_DEBUG, " head: %p\n", t->channel_head);
2288 if (NULL != t->channel_head)
2289 LOG (GNUNET_ERROR_TYPE_DEBUG, " head ch: %p\n", t->channel_head->ch);
2291 /* Get buffer space */
2292 buffer = GMT_get_connections_buffer (t);
2298 /* Count and remember choked channels */
2300 for (iter = t->channel_head; NULL != iter; iter = iter->next)
2302 if (GNUNET_NO == get_channel_allowed (iter))
2304 choked[choked_n++] = iter->ch;
2308 /* Unchoke random channels */
2309 while (0 < buffer && 0 < choked_n)
2311 unsigned int r = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2313 GMCH_allow_client (choked[r], GMCH_is_origin (choked[r], GNUNET_YES));
2316 choked[r] = choked[choked_n];
2322 * Send ACK on one or more connections due to buffer space to the client.
2324 * Iterates all connections of the tunnel and sends ACKs appropriately.
2329 GMT_send_connection_acks (struct MeshTunnel3 *t)
2331 struct MeshTConnection *iter;
2334 uint32_t allow_per_connection;
2336 unsigned int buffer;
2338 LOG (GNUNET_ERROR_TYPE_DEBUG, "Tunnel send connection ACKs on %s\n",
2347 buffer = GMT_get_channels_buffer (t);
2348 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer %u\n", buffer);
2350 /* Count connections, how many messages are already allowed */
2351 cs = GMT_count_connections (t);
2352 for (allowed = 0, iter = t->connection_head; NULL != iter; iter = iter->next)
2354 allowed += get_connection_allowed (iter);
2356 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowed %u\n", allowed);
2358 /* Make sure there is no overflow */
2359 if (allowed > buffer)
2364 /* Authorize connections to send more data */
2365 to_allow = buffer; /* - allowed; */
2367 for (iter = t->connection_head; NULL != iter && to_allow > 0; iter = iter->next)
2369 allow_per_connection = to_allow/cs;
2370 to_allow -= allow_per_connection;
2372 if (get_connection_allowed (iter) > 64 / 3)
2376 GMC_allow (iter->c, allow_per_connection,
2377 GMC_is_origin (iter->c, GNUNET_NO));
2380 GNUNET_break (to_allow == 0);
2385 * Cancel a previously sent message while it's in the queue.
2387 * ONLY can be called before the continuation given to the send function
2388 * is called. Once the continuation is called, the message is no longer in the
2391 * @param q Handle to the queue.
2394 GMT_cancel (struct MeshTunnel3Queue *q)
2399 /* message_sent() will be called and free q */
2401 else if (NULL != q->tqd)
2403 unqueue_data (q->tqd);
2405 if (NULL != q->cont)
2406 q->cont (q->cont_cls, NULL, q, 0, 0);
2417 * Sends an already built message on a tunnel, encrypting it and
2418 * choosing the best connection.
2420 * @param message Message to send. Function modifies it.
2421 * @param t Tunnel on which this message is transmitted.
2422 * @param force Force the tunnel to take the message (buffer overfill).
2423 * @param cont Continuation to call once message is really sent.
2424 * @param cont_cls Closure for @c cont.
2426 * @return Handle to cancel message. NULL if @c cont is NULL.
2428 struct MeshTunnel3Queue *
2429 GMT_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2430 struct MeshTunnel3 *t, int force,
2431 GMT_sent cont, void *cont_cls)
2433 return send_prebuilt_message (message, t, force, cont, cont_cls, NULL);
2438 * Is the tunnel directed towards the local peer?
2442 * @return #GNUNET_YES if it is loopback.
2445 GMT_is_loopback (const struct MeshTunnel3 *t)
2447 return (myid == GMP_get_short_id (t->peer));
2452 * Is the tunnel this path already?
2457 * @return #GNUNET_YES a connection uses this path.
2460 GMT_is_path_used (const struct MeshTunnel3 *t, const struct MeshPeerPath *p)
2462 struct MeshTConnection *iter;
2464 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2465 if (GMC_get_path (iter->c) == p)
2473 * Get a cost of a path for a tunnel considering existing connections.
2476 * @param path Candidate path.
2478 * @return Cost of the path (path length + number of overlapping nodes)
2481 GMT_get_path_cost (const struct MeshTunnel3 *t,
2482 const struct MeshPeerPath *path)
2484 struct MeshTConnection *iter;
2485 const struct MeshPeerPath *aux;
2486 unsigned int overlap;
2494 GNUNET_assert (NULL != t);
2496 for (i = 0; i < path->length; i++)
2498 for (iter = t->connection_head; NULL != iter; iter = iter->next)
2500 aux = GMC_get_path (iter->c);
2504 for (j = 0; j < aux->length; j++)
2506 if (path->peers[i] == aux->peers[j])
2514 return (path->length + overlap) * (path->score * -1);
2519 * Get the static string for the peer this tunnel is directed.
2523 * @return Static string the destination peer's ID.
2526 GMT_2s (const struct MeshTunnel3 *t)
2531 return GMP_2s (t->peer);
2536 * Log all possible info about the tunnel state.
2538 * @param t Tunnel to debug.
2541 GMT_debug (const struct MeshTunnel3 *t)
2543 struct MeshTChannel *iterch;
2544 struct MeshTConnection *iterc;
2546 LOG (GNUNET_ERROR_TYPE_DEBUG, "DEBUG TUNNEL TOWARDS %s\n", GMT_2s (t));
2547 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate %s, estate %s\n",
2548 cstate2s (t->cstate), estate2s (t->estate));
2549 LOG (GNUNET_ERROR_TYPE_DEBUG, " kx_ctx %p, rekey_task %u\n",
2550 t->kx_ctx, t->rekey_task);
2551 LOG (GNUNET_ERROR_TYPE_DEBUG, " tq_head %p, tq_tail %p\n",
2552 t->tq_head, t->tq_tail);
2553 LOG (GNUNET_ERROR_TYPE_DEBUG, " destroy %u\n", t->destroy);
2555 LOG (GNUNET_ERROR_TYPE_DEBUG, " channels:\n");
2556 for (iterch = t->channel_head; NULL != iterch; iterch = iterch->next)
2558 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %s\n", GMCH_2s (iterch->ch));
2561 LOG (GNUNET_ERROR_TYPE_DEBUG, " connections:\n");
2562 for (iterc = t->connection_head; NULL != iterc; iterc = iterc->next)
2564 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %s [%u] buf: %u/%u (qn %u/%u)\n",
2565 GMC_2s (iterc->c), GMC_get_state (iterc->c),
2566 GMC_get_buffer (iterc->c, GNUNET_YES),
2567 GMC_get_buffer (iterc->c, GNUNET_NO),
2568 GMC_get_qn (iterc->c, GNUNET_YES),
2569 GMC_get_qn (iterc->c, GNUNET_NO));
2572 LOG (GNUNET_ERROR_TYPE_DEBUG, "DEBUG TUNNEL END\n");