src/transport/gnunet-service-transport_neighbours.c

   1 /*
   2      This file is part of GNUnet.
   3      (C) 2010,2011 Christian Grothoff (and other contributing authors)
   4
   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.
   9
  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.
  14
  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.
  19 */
  20
  21 /**
  22  * @file transport/gnunet-service-transport_neighbours.c
  23  * @brief neighbour management
  24  * @author Christian Grothoff
  25  */
  26 #include "platform.h"
  27 #include "gnunet_ats_service.h"
  28 #include "gnunet-service-transport_neighbours.h"
  29 #include "gnunet-service-transport_plugins.h"
  30 #include "gnunet-service-transport_validation.h"
  31 #include "gnunet-service-transport_clients.h"
  32 #include "gnunet-service-transport.h"
  33 #include "gnunet_peerinfo_service.h"
  34 #include "gnunet-service-transport_blacklist.h"
  35 #include "gnunet_constants.h"
  36 #include "transport.h"
  37
  38
  39 /**
  40  * Size of the neighbour hash map.
  41  */
  42 #define NEIGHBOUR_TABLE_SIZE 256
  43
  44 /**
  45  * How often must a peer violate bandwidth quotas before we start
  46  * to simply drop its messages?
  47  */
  48 #define QUOTA_VIOLATION_DROP_THRESHOLD 10
  49
  50 /**
  51  * How often do we send KEEPALIVE messages to each of our neighbours?
  52  * (idle timeout is 5 minutes or 300 seconds, so with 90s interval we
  53  * send 3 keepalives in each interval, so 3 messages would need to be
  54  * lost in a row for a disconnect).
  55  */
  56 #define KEEPALIVE_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 90)
  57
  58
  59 #define ATS_RESPONSE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 3)
  60
  61
  62 #define SETUP_CONNECTION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
  63
  64
  65 /**
  66  * Entry in neighbours.
  67  */
  68 struct NeighbourMapEntry;
  69
  70 /**
  71  * Message a peer sends to another to indicate its
  72  * preference for communicating via a particular
  73  * session (and the desire to establish a real
  74  * connection).
  75  */
  76 struct SessionConnectMessage
  77 {
  78   /**
  79    * Header of type 'GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_CONNECT'
  80    */
  81   struct GNUNET_MessageHeader header;
  82
  83   /**
  84    * Always zero.
  85    */
  86   uint32_t reserved GNUNET_PACKED;
  87
  88   /**
  89    * Absolute time at the sender.  Only the most recent connect
  90    * message implies which session is preferred by the sender.
  91    */
  92   struct GNUNET_TIME_AbsoluteNBO timestamp;
  93
  94 };
  95
  96
  97 struct SessionDisconnectMessage
  98 {
  99   /**
 100    * Header of type 'GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT'
 101    */
 102   struct GNUNET_MessageHeader header;
 103
 104   /**
 105    * Always zero.
 106    */
 107   uint32_t reserved GNUNET_PACKED;
 108
 109   /**
 110    * Purpose of the signature.  Extends over the timestamp.
 111    * Purpose should be GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DISCONNECT.
 112    */
 113   struct GNUNET_CRYPTO_RsaSignaturePurpose purpose;
 114
 115   /**
 116    * Absolute time at the sender.  Only the most recent connect
 117    * message implies which session is preferred by the sender.
 118    */
 119   struct GNUNET_TIME_AbsoluteNBO timestamp;
 120
 121   /**
 122    * Public key of the sender.
 123    */
 124   struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded public_key;
 125
 126   /**
 127    * Signature of the peer that sends us the disconnect.  Only
 128    * valid if the timestamp is AFTER the timestamp from the
 129    * corresponding 'CONNECT' message.
 130    */
 131   struct GNUNET_CRYPTO_RsaSignature signature;
 132
 133 };
 134
 135
 136 /**
 137  * For each neighbour we keep a list of messages
 138  * that we still want to transmit to the neighbour.
 139  */
 140 struct MessageQueue
 141 {
 142
 143   /**
 144    * This is a doubly linked list.
 145    */
 146   struct MessageQueue *next;
 147
 148   /**
 149    * This is a doubly linked list.
 150    */
 151   struct MessageQueue *prev;
 152
 153   /**
 154    * Once this message is actively being transmitted, which
 155    * neighbour is it associated with?
 156    */
 157   struct NeighbourMapEntry *n;
 158
 159   /**
 160    * Function to call once we're done.
 161    */
 162   GST_NeighbourSendContinuation cont;
 163
 164   /**
 165    * Closure for 'cont'
 166    */
 167   void *cont_cls;
 168
 169   /**
 170    * The message(s) we want to transmit, GNUNET_MessageHeader(s)
 171    * stuck together in memory.  Allocated at the end of this struct.
 172    */
 173   const char *message_buf;
 174
 175   /**
 176    * Size of the message buf
 177    */
 178   size_t message_buf_size;
 179
 180   /**
 181    * At what time should we fail?
 182    */
 183   struct GNUNET_TIME_Absolute timeout;
 184
 185 };
 186
 187 enum State
 188 {
 189     /* fresh peer or completely disconnected */
 190     S_NOT_CONNECTED = 0,
 191     /* sent CONNECT message to other peer, waiting for CONNECT_ACK */
 192     S_CONNECT_SENT = 1,
 193     /* received CONNECT message to other peer, sending CONNECT_ACK */
 194     S_CONNECT_RECV = 4,
 195     /* sent CONNECT_ACK message to other peer, wait for ACK or payload */
 196     S_CONNECT_RECV_ACK_SENT = 8,
 197     /* received ACK or payload */
 198     S_CONNECTED = 16,
 199     /* Disconnect in progress */
 200     S_DISCONNECT = 32
 201 };
 202
 203 /**
 204  * Entry in neighbours.
 205  */
 206 struct NeighbourMapEntry
 207 {
 208
 209   /**
 210    * Head of list of messages we would like to send to this peer;
 211    * must contain at most one message per client.
 212    */
 213   struct MessageQueue *messages_head;
 214
 215   /**
 216    * Tail of list of messages we would like to send to this peer; must
 217    * contain at most one message per client.
 218    */
 219   struct MessageQueue *messages_tail;
 220
 221   /**
 222    * Performance data for the peer.
 223    */
 224   //struct GNUNET_ATS_Information *ats;
 225
 226   /**
 227    * Are we currently trying to send a message? If so, which one?
 228    */
 229   struct MessageQueue *is_active;
 230
 231   /**
 232    * Active session for communicating with the peer.
 233    */
 234   struct Session *session;
 235
 236   /**
 237    * Name of the plugin we currently use.
 238    */
 239   char *plugin_name;
 240
 241   /**
 242    * Address used for communicating with the peer, NULL for inbound connections.
 243    */
 244   void *addr;
 245
 246   /**
 247    * Number of bytes in 'addr'.
 248    */
 249   size_t addrlen;
 250
 251   /**
 252    * Identity of this neighbour.
 253    */
 254   struct GNUNET_PeerIdentity id;
 255
 256   /**
 257    * ID of task scheduled to run when this peer is about to
 258    * time out (will free resources associated with the peer).
 259    */
 260   GNUNET_SCHEDULER_TaskIdentifier timeout_task;
 261
 262   /**
 263    * ID of task scheduled to send keepalives.
 264    */
 265   GNUNET_SCHEDULER_TaskIdentifier keepalive_task;
 266
 267   /**
 268    * ID of task scheduled to run when we should try transmitting
 269    * the head of the message queue.
 270    */
 271   GNUNET_SCHEDULER_TaskIdentifier transmission_task;
 272
 273   /**
 274    * Tracker for inbound bandwidth.
 275    */
 276   struct GNUNET_BANDWIDTH_Tracker in_tracker;
 277
 278   /**
 279    * Inbound bandwidth from ATS, activated when connection is up
 280    */
 281   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in;
 282
 283   /**
 284    * Inbound bandwidth from ATS, activated when connection is up
 285    */
 286   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out;
 287
 288   /**
 289    * Timestamp of the 'SESSION_CONNECT' message we got from the other peer
 290    */
 291   struct GNUNET_TIME_Absolute connect_ts;
 292
 293   /**
 294    * Timeout for ATS
 295    * We asked ATS for a new address for this peer
 296    */
 297   GNUNET_SCHEDULER_TaskIdentifier ats_suggest;
 298
 299   /**
 300    * Task the resets the peer state after due to an pending
 301    * unsuccessful connection setup
 302    */
 303   GNUNET_SCHEDULER_TaskIdentifier state_reset;
 304
 305   /**
 306    * How often has the other peer (recently) violated the inbound
 307    * traffic limit?  Incremented by 10 per violation, decremented by 1
 308    * per non-violation (for each time interval).
 309    */
 310   unsigned int quota_violation_count;
 311
 312
 313   /**
 314    * The current state of the peer
 315    * Element of enum State
 316    */
 317   int state;
 318
 319 };
 320
 321
 322 /**
 323  * All known neighbours and their HELLOs.
 324  */
 325 static struct GNUNET_CONTAINER_MultiHashMap *neighbours;
 326
 327 /**
 328  * Closure for connect_notify_cb and disconnect_notify_cb
 329  */
 330 static void *callback_cls;
 331
 332 /**
 333  * Function to call when we connected to a neighbour.
 334  */
 335 static GNUNET_TRANSPORT_NotifyConnect connect_notify_cb;
 336
 337 /**
 338  * Function to call when we disconnected from a neighbour.
 339  */
 340 static GNUNET_TRANSPORT_NotifyDisconnect disconnect_notify_cb;
 341
 342 /**
 343  * counter for connected neighbours
 344  */
 345 static int neighbours_connected;
 346
 347 /**
 348  * Lookup a neighbour entry in the neighbours hash map.
 349  *
 350  * @param pid identity of the peer to look up
 351  * @return the entry, NULL if there is no existing record
 352  */
 353 static struct NeighbourMapEntry *
 354 lookup_neighbour (const struct GNUNET_PeerIdentity *pid)
 355 {
 356   return GNUNET_CONTAINER_multihashmap_get (neighbours, &pid->hashPubKey);
 357 }
 358
 359 #define change_state(n, state, ...) change (n, state, __LINE__)
 360
 361 static int
 362 is_connecting (struct NeighbourMapEntry * n)
 363 {
 364   if ((n->state > S_NOT_CONNECTED) && (n->state < S_CONNECTED))
 365     return GNUNET_YES;
 366   return GNUNET_NO;
 367 }
 368
 369 static int
 370 is_connected (struct NeighbourMapEntry * n)
 371 {
 372   if (n->state == S_CONNECTED)
 373     return GNUNET_YES;
 374   return GNUNET_NO;
 375 }
 376
 377 static int
 378 is_disconnecting (struct NeighbourMapEntry * n)
 379 {
 380   if (n->state == S_DISCONNECT)
 381     return GNUNET_YES;
 382   return GNUNET_NO;
 383 }
 384
 385 static const char *
 386 print_state (int state)
 387 {
 388   switch (state) {
 389     case S_CONNECTED:
 390         return "S_CONNECTED";
 391       break;
 392     case S_CONNECT_RECV:
 393       return "S_CONNECT_RECV";
 394       break;
 395     case S_CONNECT_RECV_ACK_SENT:
 396       return"S_CONNECT_RECV_ACK_SENT";
 397       break;
 398     case S_CONNECT_SENT:
 399       return "S_CONNECT_SENT";
 400       break;
 401     case S_DISCONNECT:
 402       return "S_DISCONNECT";
 403       break;
 404     case S_NOT_CONNECTED:
 405       return "S_NOT_CONNECTED";
 406       break;
 407     default:
 408       GNUNET_break (0);
 409       break;
 410   }
 411   return NULL;
 412 }
 413
 414 static int
 415 change (struct NeighbourMapEntry * n, int state, int line);
 416
 417 static void
 418 ats_suggest_cancel (void *cls,
 419     const struct GNUNET_SCHEDULER_TaskContext *tc);
 420
 421 static void
 422 reset_task (void *cls,
 423             const struct GNUNET_SCHEDULER_TaskContext *tc)
 424 {
 425   struct NeighbourMapEntry * n = cls;
 426
 427   n->state_reset = GNUNET_SCHEDULER_NO_TASK;
 428
 429 #if DEBUG_TRANSPORT
 430   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 431       "Connection to peer `%s' %s failed in state `%s', resetting connection attempt \n",
 432       GNUNET_i2s (&n->id), GST_plugins_a2s(n->plugin_name, n->addr, n->addrlen), print_state(n->state));
 433 #endif
 434   GNUNET_STATISTICS_update (GST_stats,
 435                             gettext_noop ("# failed connection attempts due to timeout"),
 436                             1,
 437                             GNUNET_NO);
 438
 439   /* resetting state */
 440   n->state = S_NOT_CONNECTED;
 441
 442   /* destroying address */
 443   GNUNET_ATS_address_destroyed (GST_ats,
 444                                 &n->id,
 445                                 n->plugin_name,
 446                                 n->addr,
 447                                 n->addrlen,
 448                                 NULL);
 449
 450   /* request new address */
 451   if (n->ats_suggest != GNUNET_SCHEDULER_NO_TASK)
 452     GNUNET_SCHEDULER_cancel(n->ats_suggest);
 453   n->ats_suggest = GNUNET_SCHEDULER_add_delayed (ATS_RESPONSE_TIMEOUT, ats_suggest_cancel, n);
 454   GNUNET_ATS_suggest_address(GST_ats, &n->id);
 455 }
 456
 457 static int
 458 change (struct NeighbourMapEntry * n, int state, int line)
 459 {
 460   char * old = strdup(print_state(n->state));
 461   char * new = strdup(print_state(state));
 462
 463   /* allowed transitions */
 464   int allowed = GNUNET_NO;
 465   switch (n->state) {
 466   case S_NOT_CONNECTED:
 467     if ((state == S_CONNECT_RECV) || (state == S_CONNECT_SENT) ||
 468         (state == S_DISCONNECT))
 469     {
 470       allowed = GNUNET_YES;
 471
 472       /* Schedule reset task */
 473       if ((state == S_CONNECT_RECV) || (state == S_CONNECT_SENT) )
 474       {
 475         GNUNET_assert (n->state_reset == GNUNET_SCHEDULER_NO_TASK);
 476         n->state_reset = GNUNET_SCHEDULER_add_delayed (SETUP_CONNECTION_TIMEOUT, &reset_task, n);
 477       }
 478
 479       break;
 480     }
 481     break;
 482   case S_CONNECT_RECV:
 483     if ((state == S_NOT_CONNECTED) || (state == S_DISCONNECT) ||
 484         (state == S_CONNECTED) || /* FIXME SENT -> RECV ISSUE!*/ (state == S_CONNECT_SENT))
 485     {
 486       if ((state == S_CONNECTED) || (state == S_DISCONNECT) || (state == S_NOT_CONNECTED))
 487       {
 488 #if DEBUG_TRANSPORT
 489         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 490             "Removed reset task for peer `%s' %s failed in state transition `%s' -> `%s' \n",
 491             GNUNET_i2s (&n->id), GST_plugins_a2s(n->plugin_name, n->addr, n->addrlen), print_state(n->state), print_state(state));
 492 #endif
 493         GNUNET_assert (n->state_reset != GNUNET_SCHEDULER_NO_TASK);
 494         GNUNET_SCHEDULER_cancel (n->state_reset);
 495         n->state_reset = GNUNET_SCHEDULER_NO_TASK;
 496       }
 497
 498       allowed = GNUNET_YES;
 499       break;
 500     }
 501     break;
 502   case S_CONNECT_SENT:
 503     if ((state == S_NOT_CONNECTED) || (state == S_CONNECTED) ||
 504         (state == S_DISCONNECT) || /* FIXME SENT -> RECV ISSUE!*/ (state == S_CONNECT_RECV))
 505     {
 506       if ((state == S_CONNECTED) || (state == S_DISCONNECT) || (state == S_NOT_CONNECTED))
 507       {
 508 #if DEBUG_TRANSPORT
 509         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 510             "Removed reset task for peer `%s' %s failed in state transition `%s' -> `%s' \n",
 511             GNUNET_i2s (&n->id), GST_plugins_a2s(n->plugin_name, n->addr, n->addrlen), print_state(n->state), print_state(state));
 512 #endif
 513         GNUNET_assert (n->state_reset != GNUNET_SCHEDULER_NO_TASK);
 514         GNUNET_SCHEDULER_cancel (n->state_reset);
 515         n->state_reset = GNUNET_SCHEDULER_NO_TASK;
 516       }
 517
 518       allowed = GNUNET_YES;
 519       break;
 520     }
 521     break;
 522   case S_CONNECTED:
 523     if (state == S_DISCONNECT)
 524     {
 525       allowed = GNUNET_YES;
 526       break;
 527     }
 528     break;
 529   case S_DISCONNECT:
 530     /*
 531     if (state == S_NOT_CONNECTED)
 532     {
 533       allowed = GNUNET_YES;
 534       break;
 535     }*/
 536     break;
 537   default:
 538     GNUNET_break (0);
 539     break;
 540
 541   }
 542
 543   if (allowed == GNUNET_NO)
 544   {
 545     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 546         "Illegal state transition from `%s' to `%s' in line %u \n",
 547         old, new, line);
 548     GNUNET_break (0);
 549     GNUNET_free (old);
 550     GNUNET_free (new);
 551     return GNUNET_SYSERR;
 552   }
 553
 554   n->state = state;
 555 #if DEBUG_TRANSPORT
 556   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "State for neighbour `%s' %X changed from `%s' to `%s' in line %u\n",
 557       GNUNET_i2s (&n->id), n, old, new, line);
 558 #endif
 559   GNUNET_free (old);
 560   GNUNET_free (new);
 561   return GNUNET_OK;
 562 }
 563
 564 static ssize_t
 565 send_with_plugin ( const struct GNUNET_PeerIdentity * target,
 566     const char *msgbuf,
 567     size_t msgbuf_size,
 568     uint32_t priority,
 569     struct GNUNET_TIME_Relative timeout,
 570     struct Session * session,
 571     const char * plugin_name,
 572     const void *addr,
 573     size_t addrlen,
 574     int force_address,
 575     GNUNET_TRANSPORT_TransmitContinuation cont,
 576     void *cont_cls)
 577
 578 {
 579   struct GNUNET_TRANSPORT_PluginFunctions *papi;
 580   size_t ret = GNUNET_SYSERR;
 581
 582   papi = GST_plugins_find (plugin_name);
 583   if (papi == NULL)
 584   {
 585     if (cont != NULL)
 586       cont (cont_cls, target, GNUNET_SYSERR);
 587     return GNUNET_SYSERR;
 588   }
 589
 590   ret = papi->send (papi->cls,
 591       target,
 592       msgbuf, msgbuf_size,
 593       0,
 594       timeout,
 595       session,
 596       addr, addrlen,
 597       GNUNET_YES,
 598       cont, cont_cls);
 599
 600   if (ret == -1)
 601   {
 602     if (cont != NULL)
 603       cont (cont_cls, target, GNUNET_SYSERR);
 604   }
 605   return ret;
 606 }
 607
 608 /**
 609  * Task invoked to start a transmission to another peer.
 610  *
 611  * @param cls the 'struct NeighbourMapEntry'
 612  * @param tc scheduler context
 613  */
 614 static void
 615 transmission_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
 616
 617
 618 /**
 619  * We're done with our transmission attempt, continue processing.
 620  *
 621  * @param cls the 'struct MessageQueue' of the message
 622  * @param receiver intended receiver
 623  * @param success whether it worked or not
 624  */
 625 static void
 626 transmit_send_continuation (void *cls,
 627                             const struct GNUNET_PeerIdentity *receiver,
 628                             int success)
 629 {
 630   struct MessageQueue *mq;
 631   struct NeighbourMapEntry *n;
 632
 633   mq = cls;
 634   n = mq->n;
 635   if (NULL != n)
 636   {
 637     GNUNET_assert (n->is_active == mq);
 638     n->is_active = NULL;
 639     if (success == GNUNET_YES)
 640     {
 641       GNUNET_assert (n->transmission_task == GNUNET_SCHEDULER_NO_TASK);
 642       n->transmission_task = GNUNET_SCHEDULER_add_now (&transmission_task, n);
 643     }
 644   }
 645 #if DEBUG_TRANSPORT
 646   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sending message of type %u was %s\n",
 647               ntohs (((struct GNUNET_MessageHeader *) mq->message_buf)->type),
 648               (success == GNUNET_OK) ? "successful" : "FAILED");
 649 #endif
 650   if (NULL != mq->cont)
 651     mq->cont (mq->cont_cls, success);
 652   GNUNET_free (mq);
 653 }
 654
 655
 656 /**
 657  * Check the ready list for the given neighbour and if a plugin is
 658  * ready for transmission (and if we have a message), do so!
 659  *
 660  * @param n target peer for which to transmit
 661  */
 662 static void
 663 try_transmission_to_peer (struct NeighbourMapEntry *n)
 664 {
 665   struct MessageQueue *mq;
 666   struct GNUNET_TIME_Relative timeout;
 667   ssize_t ret;
 668
 669   if (n->is_active != NULL)
 670   {
 671     GNUNET_break (0);
 672     return;                     /* transmission already pending */
 673   }
 674   if (n->transmission_task != GNUNET_SCHEDULER_NO_TASK)
 675   {
 676     GNUNET_break (0);
 677     return;                     /* currently waiting for bandwidth */
 678   }
 679   while (NULL != (mq = n->messages_head))
 680   {
 681     timeout = GNUNET_TIME_absolute_get_remaining (mq->timeout);
 682     if (timeout.rel_value > 0)
 683       break;
 684     GNUNET_CONTAINER_DLL_remove (n->messages_head, n->messages_tail, mq);
 685     n->is_active = mq;
 686     mq->n = n;
 687     transmit_send_continuation (mq, &n->id, GNUNET_SYSERR);     /* timeout */
 688   }
 689   if (NULL == mq)
 690     return;                     /* no more messages */
 691
 692   if (GST_plugins_find (n->plugin_name) == NULL)
 693   {
 694     GNUNET_break (0);
 695     return;
 696   }
 697   GNUNET_CONTAINER_DLL_remove (n->messages_head, n->messages_tail, mq);
 698   n->is_active = mq;
 699   mq->n = n;
 700
 701   if  ((n->session == NULL) && (n->addr == NULL) && (n->addrlen == 0))
 702   {
 703     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "No address for peer `%s'\n",
 704                 GNUNET_i2s (&n->id));
 705     transmit_send_continuation (mq, &n->id, GNUNET_SYSERR);
 706     GNUNET_assert (n->transmission_task == GNUNET_SCHEDULER_NO_TASK);
 707     n->transmission_task = GNUNET_SCHEDULER_add_now (&transmission_task, n);
 708     return;
 709   }
 710
 711   ret = send_with_plugin (&n->id,
 712                           mq->message_buf, mq->message_buf_size, 0,
 713                           timeout,
 714                           n->session, n->plugin_name, n->addr, n->addrlen,
 715                           GNUNET_YES,
 716                           &transmit_send_continuation, mq);
 717   if (ret == -1)
 718   {
 719     /* failure, but 'send' would not call continuation in this case,
 720      * so we need to do it here! */
 721     transmit_send_continuation (mq, &n->id, GNUNET_SYSERR);
 722   }
 723
 724 }
 725
 726
 727 /**
 728  * Task invoked to start a transmission to another peer.
 729  *
 730  * @param cls the 'struct NeighbourMapEntry'
 731  * @param tc scheduler context
 732  */
 733 static void
 734 transmission_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 735 {
 736   struct NeighbourMapEntry *n = cls;
 737   GNUNET_assert (NULL != lookup_neighbour(&n->id));
 738   n->transmission_task = GNUNET_SCHEDULER_NO_TASK;
 739   try_transmission_to_peer (n);
 740 }
 741
 742
 743 /**
 744  * Initialize the neighbours subsystem.
 745  *
 746  * @param cls closure for callbacks
 747  * @param connect_cb function to call if we connect to a peer
 748  * @param disconnect_cb function to call if we disconnect from a peer
 749  */
 750 void
 751 GST_neighbours_start (void *cls, GNUNET_TRANSPORT_NotifyConnect connect_cb,
 752                       GNUNET_TRANSPORT_NotifyDisconnect disconnect_cb)
 753 {
 754   callback_cls = cls;
 755   connect_notify_cb = connect_cb;
 756   disconnect_notify_cb = disconnect_cb;
 757   neighbours = GNUNET_CONTAINER_multihashmap_create (NEIGHBOUR_TABLE_SIZE);
 758 }
 759
 760
 761 static void
 762 send_disconnect_cont (void *cls,
 763     const struct GNUNET_PeerIdentity * target,
 764     int result)
 765 {
 766 #if DEBUG_TRANSPORT
 767   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sending DISCONNECT message to peer `%4s': %i\n",
 768               GNUNET_i2s (target), result);
 769 #endif
 770 }
 771
 772
 773 static int
 774 send_disconnect (const struct GNUNET_PeerIdentity * target,
 775                  const char *plugin_name,
 776                  const char *sender_address, uint16_t sender_address_len,
 777                  struct Session *session)
 778 {
 779   size_t ret;
 780   struct SessionDisconnectMessage disconnect_msg;
 781
 782 #if DEBUG_TRANSPORT
 783   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sending DISCONNECT message to peer `%4s'\n",
 784               GNUNET_i2s (target));
 785 #endif
 786
 787   disconnect_msg.header.size = htons (sizeof (struct SessionDisconnectMessage));
 788   disconnect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT);
 789   disconnect_msg.reserved = htonl (0);
 790   disconnect_msg.purpose.size = htonl (sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
 791                                        sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded) +
 792                                        sizeof (struct GNUNET_TIME_AbsoluteNBO) );
 793   disconnect_msg.purpose.purpose = htonl (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT);
 794   disconnect_msg.timestamp = GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
 795   disconnect_msg.public_key = GST_my_public_key;
 796   GNUNET_assert (GNUNET_OK ==
 797                  GNUNET_CRYPTO_rsa_sign (GST_my_private_key,
 798                                          &disconnect_msg.purpose,
 799                                          &disconnect_msg.signature));
 800
 801   ret = send_with_plugin(target,
 802                          (const char *) &disconnect_msg, sizeof (disconnect_msg),
 803                          UINT32_MAX, GNUNET_TIME_UNIT_FOREVER_REL,
 804                          session, plugin_name, sender_address,  sender_address_len,
 805                          GNUNET_YES, &send_disconnect_cont, NULL);
 806
 807   if (ret == GNUNET_SYSERR)
 808     return GNUNET_SYSERR;
 809
 810   GNUNET_STATISTICS_update (GST_stats,
 811                             gettext_noop ("# peers disconnected due to external request"), 1,
 812                             GNUNET_NO);
 813   return GNUNET_OK;
 814 }
 815
 816 /**
 817  * Disconnect from the given neighbour, clean up the record.
 818  *
 819  * @param n neighbour to disconnect from
 820  */
 821 static void
 822 disconnect_neighbour (struct NeighbourMapEntry *n)
 823 {
 824   struct MessageQueue *mq;
 825   int was_connected = is_connected(n);
 826
 827   /* send DISCONNECT MESSAGE */
 828   if (is_connected(n) || is_connecting(n))
 829   {
 830     if (GNUNET_OK == send_disconnect(&n->id, n->plugin_name, n->addr, n->addrlen, n->session))
 831       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sent DISCONNECT_MSG to `%s'\n",
 832                   GNUNET_i2s (&n->id));
 833     else
 834       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Could not send DISCONNECT_MSG to `%s'\n",
 835                   GNUNET_i2s (&n->id));
 836   }
 837
 838
 839   if (is_disconnecting(n))
 840     return;
 841   change_state (n, S_DISCONNECT);
 842
 843   while (NULL != (mq = n->messages_head))
 844   {
 845     GNUNET_CONTAINER_DLL_remove (n->messages_head, n->messages_tail, mq);
 846     if (NULL != mq->cont)
 847       mq->cont (mq->cont_cls, GNUNET_SYSERR);
 848     GNUNET_free (mq);
 849   }
 850   if (NULL != n->is_active)
 851   {
 852     n->is_active->n = NULL;
 853     n->is_active = NULL;
 854   }
 855   if (was_connected)
 856   {
 857     GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != n->keepalive_task);
 858     GNUNET_SCHEDULER_cancel (n->keepalive_task);
 859     n->keepalive_task = GNUNET_SCHEDULER_NO_TASK;
 860     GNUNET_assert (neighbours_connected > 0);
 861     neighbours_connected--;
 862     GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# peers connected"), -1,
 863                               GNUNET_NO);
 864     disconnect_notify_cb (callback_cls, &n->id);
 865   }
 866   GNUNET_assert (GNUNET_YES ==
 867                  GNUNET_CONTAINER_multihashmap_remove (neighbours,
 868                                                        &n->id.hashPubKey, n));
 869   if (GNUNET_SCHEDULER_NO_TASK != n->ats_suggest)
 870   {
 871     GNUNET_SCHEDULER_cancel (n->ats_suggest);
 872     n->ats_suggest = GNUNET_SCHEDULER_NO_TASK;
 873   }
 874   if (GNUNET_SCHEDULER_NO_TASK != n->timeout_task)
 875   {
 876     GNUNET_SCHEDULER_cancel (n->timeout_task);
 877     n->timeout_task = GNUNET_SCHEDULER_NO_TASK;
 878   }
 879   if (GNUNET_SCHEDULER_NO_TASK != n->transmission_task)
 880   {
 881     GNUNET_SCHEDULER_cancel (n->transmission_task);
 882     n->transmission_task = GNUNET_SCHEDULER_NO_TASK;
 883   }
 884   if (NULL != n->plugin_name)
 885   {
 886     GNUNET_free (n->plugin_name);
 887     n->plugin_name = NULL;
 888   }
 889   if (NULL != n->addr)
 890   {
 891     GNUNET_free (n->addr);
 892     n->addr = NULL;
 893     n->addrlen = 0;
 894   }
 895   n->session = NULL;
 896   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Deleting peer `%4s', %X\n",
 897               GNUNET_i2s (&n->id), n);
 898   GNUNET_free (n);
 899 }
 900
 901
 902 /**
 903  * Peer has been idle for too long. Disconnect.
 904  *
 905  * @param cls the 'struct NeighbourMapEntry' of the neighbour that went idle
 906  * @param tc scheduler context
 907  */
 908 static void
 909 neighbour_timeout_task (void *cls,
 910                         const struct GNUNET_SCHEDULER_TaskContext *tc)
 911 {
 912   struct NeighbourMapEntry *n = cls;
 913
 914   n->timeout_task = GNUNET_SCHEDULER_NO_TASK;
 915
 916   GNUNET_STATISTICS_update (GST_stats,
 917                             gettext_noop ("# peers disconnected due to timeout"), 1,
 918                             GNUNET_NO);
 919   disconnect_neighbour (n);
 920 }
 921
 922
 923 /**
 924  * Send another keepalive message.
 925  *
 926  * @param cls the 'struct NeighbourMapEntry' of the neighbour that went idle
 927  * @param tc scheduler context
 928  */
 929 static void
 930 neighbour_keepalive_task (void *cls,
 931                           const struct GNUNET_SCHEDULER_TaskContext *tc)
 932 {
 933   struct NeighbourMapEntry *n = cls;
 934   struct GNUNET_MessageHeader m;
 935
 936   n->keepalive_task = GNUNET_SCHEDULER_add_delayed (KEEPALIVE_FREQUENCY,
 937                                                     &neighbour_keepalive_task,
 938                                                     n);
 939   GNUNET_assert (is_connected(n));
 940   GNUNET_STATISTICS_update (GST_stats,
 941                             gettext_noop ("# keepalives sent"), 1,
 942                             GNUNET_NO);
 943   m.size = htons (sizeof (struct GNUNET_MessageHeader));
 944   m.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE);
 945
 946   send_with_plugin(&n->id, (const void *) &m,
 947                    sizeof (m),
 948                    UINT32_MAX /* priority */ ,
 949                    GNUNET_TIME_UNIT_FOREVER_REL,
 950                    n->session, n->plugin_name, n->addr, n->addrlen,
 951                    GNUNET_YES, NULL, NULL);
 952 }
 953
 954
 955 /**
 956  * Disconnect from the given neighbour.
 957  *
 958  * @param cls unused
 959  * @param key hash of neighbour's public key (not used)
 960  * @param value the 'struct NeighbourMapEntry' of the neighbour
 961  */
 962 static int
 963 disconnect_all_neighbours (void *cls, const GNUNET_HashCode * key, void *value)
 964 {
 965   struct NeighbourMapEntry *n = value;
 966
 967 #if DEBUG_TRANSPORT
 968   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Disconnecting peer `%4s', %s\n",
 969               GNUNET_i2s (&n->id), "SHUTDOWN_TASK");
 970 #endif
 971   if (is_connected(n))
 972     GNUNET_STATISTICS_update (GST_stats,
 973                               gettext_noop ("# peers disconnected due to global disconnect"), 1,
 974                               GNUNET_NO);
 975   disconnect_neighbour (n);
 976   return GNUNET_OK;
 977 }
 978
 979
 980 static void
 981 ats_suggest_cancel (void *cls,
 982     const struct GNUNET_SCHEDULER_TaskContext *tc)
 983 {
 984   struct NeighbourMapEntry *n = cls;
 985
 986   n->ats_suggest = GNUNET_SCHEDULER_NO_TASK;
 987
 988   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 989               " ATS did not suggested address to connect to peer `%s'\n",
 990               GNUNET_i2s (&n->id));
 991
 992   disconnect_neighbour(n);
 993 }
 994
 995
 996 /**
 997  * Cleanup the neighbours subsystem.
 998  */
 999 void
1000 GST_neighbours_stop ()
1001 {
1002   GNUNET_assert (neighbours != NULL);
1003
1004   GNUNET_CONTAINER_multihashmap_iterate (neighbours, &disconnect_all_neighbours,
1005                                          NULL);
1006   GNUNET_CONTAINER_multihashmap_destroy (neighbours);
1007   GNUNET_assert (neighbours_connected == 0);
1008   neighbours = NULL;
1009   callback_cls = NULL;
1010   connect_notify_cb = NULL;
1011   disconnect_notify_cb = NULL;
1012 }
1013
1014
1015 /**
1016  * We tried to send a SESSION_CONNECT message to another peer.  If this
1017  * succeeded, we change the state.  If it failed, we should tell
1018  * ATS to not use this address anymore (until it is re-validated).
1019  *
1020  * @param cls the 'struct NeighbourMapEntry'
1021  * @param success GNUNET_OK on success
1022  */
1023 static void
1024 send_connect_continuation (void *cls,
1025       const struct GNUNET_PeerIdentity * target,
1026       int success)
1027
1028 {
1029   struct NeighbourMapEntry *n = cls;
1030
1031   GNUNET_assert (n != NULL);
1032   GNUNET_assert (!is_connected(n));
1033
1034   if (is_disconnecting(n))
1035     return; /* neighbour is going away */
1036   if (GNUNET_YES != success)
1037   {
1038 #if DEBUG_TRANSPORT
1039     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1040               "Failed to send CONNECT_MSG to peer `%4s' with plugin `%s' address '%s' session %X, asking ATS for new address \n",
1041               GNUNET_i2s (&n->id), n->plugin_name,
1042               (n->addrlen == 0) ? "<inbound>" : GST_plugins_a2s (n->plugin_name,
1043                                                                   n->addr,
1044                                                                   n->addrlen),
1045               n->session);
1046 #endif
1047
1048     GNUNET_ATS_address_destroyed (GST_ats,
1049                                   &n->id,
1050                                   n->plugin_name,
1051                                   n->addr,
1052                                   n->addrlen,
1053                                   NULL);
1054
1055     if (n->ats_suggest!= GNUNET_SCHEDULER_NO_TASK)
1056       GNUNET_SCHEDULER_cancel(n->ats_suggest);
1057     n->ats_suggest = GNUNET_SCHEDULER_add_delayed (ATS_RESPONSE_TIMEOUT, ats_suggest_cancel, n);
1058     GNUNET_ATS_suggest_address(GST_ats, &n->id);
1059     return;
1060   }
1061   change_state(n, S_CONNECT_SENT);
1062 }
1063
1064
1065 /**
1066  * We tried to switch addresses with an peer already connected. If it failed,
1067  * we should tell ATS to not use this address anymore (until it is re-validated).
1068  *
1069  * @param cls the 'struct NeighbourMapEntry'
1070  * @param success GNUNET_OK on success
1071  */
1072 static void
1073 send_switch_address_continuation (void *cls,
1074       const struct GNUNET_PeerIdentity * target,
1075       int success)
1076
1077 {
1078   struct NeighbourMapEntry *n = cls;
1079
1080   GNUNET_assert (n != NULL);
1081   if (is_disconnecting(n))
1082     return; /* neighbour is going away */
1083
1084   GNUNET_assert (n->state == S_CONNECTED);
1085   if (GNUNET_YES != success)
1086   {
1087 #if DEBUG_TRANSPORT
1088     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1089               "Failed to switch connected peer `%s' to plugin `%s' address '%s' session %X, asking ATS for new address \n",
1090               GNUNET_i2s (&n->id), n->plugin_name,
1091               (n->addrlen == 0) ? "<inbound>" : GST_plugins_a2s (n->plugin_name,
1092                                                                   n->addr,
1093                                                                   n->addrlen),
1094               n->session);
1095 #endif
1096
1097     GNUNET_ATS_address_destroyed (GST_ats,
1098                                   &n->id,
1099                                   n->plugin_name,
1100                                   n->addr,
1101                                   n->addrlen,
1102                                   NULL);
1103
1104     if (n->ats_suggest != GNUNET_SCHEDULER_NO_TASK)
1105       GNUNET_SCHEDULER_cancel(n->ats_suggest);
1106     n->ats_suggest = GNUNET_SCHEDULER_add_delayed (ATS_RESPONSE_TIMEOUT, ats_suggest_cancel, n);
1107     GNUNET_ATS_suggest_address(GST_ats, &n->id);
1108     return;
1109   }
1110 }
1111
1112 /**
1113  * We tried to send a SESSION_CONNECT message to another peer.  If this
1114  * succeeded, we change the state.  If it failed, we should tell
1115  * ATS to not use this address anymore (until it is re-validated).
1116  *
1117  * @param cls the 'struct NeighbourMapEntry'
1118  * @param success GNUNET_OK on success
1119  */
1120 static void
1121 send_connect_ack_continuation (void *cls,
1122       const struct GNUNET_PeerIdentity * target,
1123       int success)
1124
1125 {
1126   struct NeighbourMapEntry *n = cls;
1127
1128   GNUNET_assert (n != NULL);
1129
1130   if (GNUNET_YES == success)
1131     return; /* sending successful */
1132
1133   /* sending failed, ask for next address  */
1134 #if DEBUG_TRANSPORT
1135     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1136               "Failed to send CONNECT_MSG to peer `%4s' with plugin `%s' address '%s' session %X, asking ATS for new address \n",
1137               GNUNET_i2s (&n->id), n->plugin_name,
1138               (n->addrlen == 0) ? "<inbound>" : GST_plugins_a2s (n->plugin_name,
1139                                                                   n->addr,
1140                                                                   n->addrlen),
1141               n->session);
1142 #endif
1143     change_state(n, S_NOT_CONNECTED);
1144
1145     GNUNET_ATS_address_destroyed (GST_ats,
1146                                   &n->id,
1147                                   n->plugin_name,
1148                                   n->addr,
1149                                   n->addrlen,
1150                                   NULL);
1151
1152     if (n->ats_suggest != GNUNET_SCHEDULER_NO_TASK)
1153       GNUNET_SCHEDULER_cancel(n->ats_suggest);
1154     n->ats_suggest = GNUNET_SCHEDULER_add_delayed (ATS_RESPONSE_TIMEOUT, ats_suggest_cancel, n);
1155     GNUNET_ATS_suggest_address(GST_ats, &n->id);
1156 }
1157
1158 /**
1159  * For an existing neighbour record, set the active connection to
1160  * the given address.
1161  *
1162  * @param peer identity of the peer to switch the address for
1163  * @param plugin_name name of transport that delivered the PONG
1164  * @param address address of the other peer, NULL if other peer
1165  *                       connected to us
1166  * @param address_len number of bytes in address
1167  * @param session session to use (or NULL)
1168  * @param ats performance data
1169  * @param ats_count number of entries in ats
1170  * @return GNUNET_YES if we are currently connected, GNUNET_NO if the
1171  *         connection is not up (yet)
1172  */
1173 int
1174 GST_neighbours_switch_to_address_3way (const struct GNUNET_PeerIdentity *peer,
1175                                   const char *plugin_name, const void *address,
1176                                   size_t address_len, struct Session *session,
1177                                   const struct GNUNET_ATS_Information
1178                                   *ats, uint32_t ats_count,
1179                                   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
1180                                   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
1181 {
1182   struct NeighbourMapEntry *n;
1183   struct SessionConnectMessage connect_msg;
1184   size_t msg_len;
1185   size_t ret;
1186
1187   GNUNET_assert (neighbours != NULL);
1188   n = lookup_neighbour (peer);
1189   if (NULL == n)
1190   {
1191     if (NULL == session)
1192       GNUNET_ATS_address_destroyed (GST_ats,
1193                                     peer,
1194                                     plugin_name, address,
1195                                     address_len, NULL);
1196     return GNUNET_NO;
1197   }
1198
1199   if (n->ats_suggest != GNUNET_SCHEDULER_NO_TASK)
1200   {
1201     GNUNET_SCHEDULER_cancel(n->ats_suggest);
1202     n->ats_suggest = GNUNET_SCHEDULER_NO_TASK;
1203   }
1204
1205 #if DEBUG_TRANSPORT
1206   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1207               "ATS tells us to switch to plugin `%s' address '%s' session %X for %s peer `%s'\n",
1208               plugin_name,
1209               (address_len == 0) ? "<inbound>" : GST_plugins_a2s (plugin_name,
1210                                                                   address,
1211                                                                   address_len),
1212               session, (is_connected(n) ? "CONNECTED" : "NOT CONNECTED"),
1213               GNUNET_i2s (peer));
1214 #endif
1215
1216   // do not switch addresses just update quotas
1217   if (n != NULL)
1218   {
1219     if ((is_connected(n)) && (address_len == n->addrlen))
1220     {
1221       if ((0 == memcmp (address, n->addr, address_len)) &&
1222           (n->session == session))
1223       {
1224         struct QuotaSetMessage q_msg;
1225
1226 #if DEBUG_TRANSPORT
1227   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1228               "Sending outbound quota of %u Bps and inbound quota of % Bps for peer `%s' to all clients\n",
1229               ntohl (n->bandwidth_out.value__),
1230               ntohl (n->bandwidth_in.value__),
1231               GNUNET_i2s (peer));
1232 #endif
1233
1234         n->bandwidth_in = bandwidth_in;
1235         n->bandwidth_out = bandwidth_out;
1236         GST_neighbours_set_incoming_quota(&n->id, n->bandwidth_in);
1237
1238         q_msg.header.size = htons (sizeof (struct QuotaSetMessage));
1239         q_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA);
1240         q_msg.quota = n->bandwidth_out;
1241         q_msg.peer = (*peer);
1242         GST_clients_broadcast (&q_msg.header, GNUNET_NO);
1243         return GNUNET_NO;
1244       }
1245     }
1246   }
1247
1248   GNUNET_free_non_null (n->addr);
1249   n->addr = GNUNET_malloc (address_len);
1250   memcpy (n->addr, address, address_len);
1251   n->bandwidth_in = bandwidth_in;
1252   n->bandwidth_out = bandwidth_out;
1253   n->addrlen = address_len;
1254   n->session = session;
1255   GNUNET_free_non_null (n->plugin_name);
1256   n->plugin_name = GNUNET_strdup (plugin_name);
1257   GNUNET_SCHEDULER_cancel (n->timeout_task);
1258   n->timeout_task =
1259       GNUNET_SCHEDULER_add_delayed (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
1260                                     &neighbour_timeout_task, n);
1261
1262   if (n->state == S_DISCONNECT)
1263   {
1264     /* We are disconnecting, nothing to do here */
1265     return GNUNET_NO;
1266   }
1267   /* We are not connected/connecting and initiate a fresh connect */
1268   if (n->state == S_NOT_CONNECTED)
1269   {
1270     msg_len = sizeof (struct SessionConnectMessage);
1271     connect_msg.header.size = htons (msg_len);
1272     connect_msg.header.type =
1273         htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_CONNECT);
1274     connect_msg.reserved = htonl (0);
1275     connect_msg.timestamp =
1276         GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
1277
1278     ret = send_with_plugin (peer, (const char *) &connect_msg, msg_len, UINT32_MAX, GNUNET_TIME_UNIT_FOREVER_REL,
1279                             session, plugin_name, address, address_len,
1280                             GNUNET_YES, &send_connect_continuation, n);
1281
1282     return GNUNET_NO;
1283   }
1284   /* We received a CONNECT message and asked ATS for an address */
1285   else if (n->state == S_CONNECT_RECV)
1286   {
1287     msg_len = sizeof (struct SessionConnectMessage);
1288     connect_msg.header.size = htons (msg_len);
1289     connect_msg.header.type =
1290       htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_CONNECT_ACK);
1291     connect_msg.reserved = htonl (0);
1292     connect_msg.timestamp = GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
1293
1294     ret = send_with_plugin(&n->id, (const void *) &connect_msg, msg_len, UINT32_MAX, GNUNET_TIME_UNIT_FOREVER_REL,
1295                            session, plugin_name, address, address_len,
1296                            GNUNET_YES, &send_connect_ack_continuation, n);
1297     return GNUNET_NO;
1298   }
1299   /* connected peer is switching addresses */
1300   else if (n->state == S_CONNECTED)
1301   {
1302     msg_len = sizeof (struct SessionConnectMessage);
1303     connect_msg.header.size = htons (msg_len);
1304     connect_msg.header.type =
1305         htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_CONNECT);
1306     connect_msg.reserved = htonl (0);
1307     connect_msg.timestamp =
1308         GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
1309
1310     ret = send_with_plugin (peer, (const char *) &connect_msg, msg_len, UINT32_MAX, GNUNET_TIME_UNIT_FOREVER_REL,
1311                             session, plugin_name, address, address_len,
1312                             GNUNET_YES, &send_switch_address_continuation, n);
1313     if (ret == GNUNET_SYSERR)
1314     {
1315       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1316                 "Failed to send CONNECT_MESSAGE to `%4s' using plugin `%s' address '%s' session %X\n",
1317                 GNUNET_i2s (peer), plugin_name,
1318                 (address_len == 0) ? "<inbound>" : GST_plugins_a2s (plugin_name,
1319                                                                     address,
1320                                                                     address_len),
1321                 session);
1322     }
1323     return GNUNET_NO;
1324   }
1325   else if (n->state == S_CONNECT_SENT)
1326   {
1327       //FIXME
1328      return GNUNET_NO;
1329   }
1330   GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Invalid connection state to switch addresses %u \n", n->state);
1331   GNUNET_break_op (0);
1332   return GNUNET_NO;
1333 }
1334
1335
1336 /**
1337  * Create an entry in the neighbour map for the given peer
1338  *
1339  * @param peer peer to create an entry for
1340  * @return new neighbour map entry
1341  */
1342 static struct NeighbourMapEntry *
1343 setup_neighbour (const struct GNUNET_PeerIdentity *peer)
1344 {
1345   struct NeighbourMapEntry *n;
1346
1347 #if DEBUG_TRANSPORT
1348   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1349               "Unknown peer `%s', creating new neighbour\n",
1350               GNUNET_i2s (peer));
1351 #endif
1352   n = GNUNET_malloc (sizeof (struct NeighbourMapEntry));
1353   n->id = *peer;
1354   n->state = S_NOT_CONNECTED;
1355   GNUNET_BANDWIDTH_tracker_init (&n->in_tracker,
1356                                  GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
1357                                  MAX_BANDWIDTH_CARRY_S);
1358   n->timeout_task =
1359     GNUNET_SCHEDULER_add_delayed (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
1360                                   &neighbour_timeout_task, n);
1361   GNUNET_assert (GNUNET_OK ==
1362                  GNUNET_CONTAINER_multihashmap_put (neighbours,
1363                                                     &n->id.hashPubKey, n,
1364                                                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
1365   return n;
1366 }
1367
1368
1369 /**
1370  * Try to create a connection to the given target (eventually).
1371  *
1372  * @param target peer to try to connect to
1373  */
1374 void
1375 GST_neighbours_try_connect (const struct GNUNET_PeerIdentity *target)
1376 {
1377   struct NeighbourMapEntry *n;
1378
1379   GNUNET_assert (neighbours != NULL);
1380 #if DEBUG_TRANSPORT
1381   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Trying to connect to peer `%s'\n",
1382               GNUNET_i2s (target));
1383 #endif
1384   GNUNET_assert (0 !=
1385                  memcmp (target, &GST_my_identity,
1386                          sizeof (struct GNUNET_PeerIdentity)));
1387   n = lookup_neighbour (target);
1388
1389   if (NULL != n)
1390   {
1391     if ((is_connected(n)) || (is_connecting(n)))
1392       return;                     /* already connecting or connected */
1393     if (is_disconnecting(n))
1394       change_state (n, S_NOT_CONNECTED);
1395   }
1396
1397
1398   if (n == NULL)
1399     n = setup_neighbour (target);
1400 #if DEBUG_TRANSPORT
1401   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1402               "Asking ATS for suggested address to connect to peer `%s'\n",
1403               GNUNET_i2s (&n->id));
1404 #endif
1405
1406    GNUNET_ATS_suggest_address (GST_ats, &n->id);
1407 }
1408
1409 /**
1410  * Test if we're connected to the given peer.
1411  *
1412  * @param target peer to test
1413  * @return GNUNET_YES if we are connected, GNUNET_NO if not
1414  */
1415 int
1416 GST_neighbours_test_connected (const struct GNUNET_PeerIdentity *target)
1417 {
1418   struct NeighbourMapEntry *n;
1419
1420   GNUNET_assert (neighbours != NULL);
1421
1422   n = lookup_neighbour (target);
1423
1424   if ((NULL == n) || (!is_connected(n)))
1425     return GNUNET_NO;           /* not connected */
1426   return GNUNET_YES;
1427 }
1428
1429
1430 /**
1431  * A session was terminated. Take note.
1432  *
1433  * @param peer identity of the peer where the session died
1434  * @param session session that is gone
1435  */
1436 void
1437 GST_neighbours_session_terminated (const struct GNUNET_PeerIdentity *peer,
1438                                    struct Session *session)
1439 {
1440   struct NeighbourMapEntry *n;
1441
1442   GNUNET_assert (neighbours != NULL);
1443
1444 #if DEBUG_TRANSPORT
1445   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1446               "Session %X to peer `%s' ended \n",
1447               session, GNUNET_i2s (peer));
1448 #endif
1449
1450   n = lookup_neighbour (peer);
1451   if (NULL == n)
1452     return;
1453   if (session != n->session)
1454     return;                     /* doesn't affect us */
1455
1456   n->session = NULL;
1457   GNUNET_free (n->addr);
1458   n->addr = NULL;
1459   n->addrlen = 0;
1460
1461   /* not connected anymore anyway, shouldn't matter */
1462   if ((!is_connected(n)) && (!is_connecting(n)))
1463     return;
1464
1465   /* We are connected, so ask ATS to switch addresses */
1466   GNUNET_SCHEDULER_cancel (n->timeout_task);
1467   n->timeout_task =
1468       GNUNET_SCHEDULER_add_delayed (GNUNET_CONSTANTS_DISCONNECT_SESSION_TIMEOUT,
1469                                     &neighbour_timeout_task, n);
1470   /* try QUICKLY to re-establish a connection, reduce timeout! */
1471   if (n->ats_suggest != GNUNET_SCHEDULER_NO_TASK)
1472     GNUNET_SCHEDULER_cancel(n->ats_suggest);
1473   n->ats_suggest = GNUNET_SCHEDULER_add_delayed (ATS_RESPONSE_TIMEOUT, ats_suggest_cancel, n);
1474   GNUNET_ATS_suggest_address (GST_ats, peer);
1475 }
1476
1477
1478 /**
1479  * Transmit a message to the given target using the active connection.
1480  *
1481  * @param target destination
1482  * @param msg message to send
1483  * @param msg_size number of bytes in msg
1484  * @param timeout when to fail with timeout
1485  * @param cont function to call when done
1486  * @param cont_cls closure for 'cont'
1487  */
1488 void
1489 GST_neighbours_send (const struct GNUNET_PeerIdentity *target, const void *msg,
1490                      size_t msg_size, struct GNUNET_TIME_Relative timeout,
1491                      GST_NeighbourSendContinuation cont, void *cont_cls)
1492 {
1493   struct NeighbourMapEntry *n;
1494   struct MessageQueue *mq;
1495
1496   GNUNET_assert (neighbours != NULL);
1497
1498   n = lookup_neighbour (target);
1499   if ((n == NULL) || (!is_connected(n)))
1500   {
1501     GNUNET_STATISTICS_update (GST_stats,
1502                               gettext_noop
1503                               ("# messages not sent (no such peer or not connected)"),
1504                               1, GNUNET_NO);
1505 #if DEBUG_TRANSPORT
1506     if (n == NULL)
1507       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1508                   "Could not send message to peer `%s': unknown neighbour",
1509                   GNUNET_i2s (target));
1510     else if (!is_connected(n))
1511       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1512                   "Could not send message to peer `%s': not connected\n",
1513                   GNUNET_i2s (target));
1514 #endif
1515     if (NULL != cont)
1516       cont (cont_cls, GNUNET_SYSERR);
1517     return;
1518   }
1519
1520   if ((n->session == NULL) && (n->addr == NULL) && (n->addrlen ==0))
1521   {
1522     GNUNET_STATISTICS_update (GST_stats,
1523                               gettext_noop
1524                               ("# messages not sent (no such peer or not connected)"),
1525                               1, GNUNET_NO);
1526 #if DEBUG_TRANSPORT
1527       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1528                   "Could not send message to peer `%s': no address available\n",
1529                   GNUNET_i2s (target));
1530 #endif
1531
1532     if (NULL != cont)
1533       cont (cont_cls, GNUNET_SYSERR);
1534     return;
1535   }
1536
1537   GNUNET_assert (msg_size >= sizeof (struct GNUNET_MessageHeader));
1538   GNUNET_STATISTICS_update (GST_stats,
1539                             gettext_noop
1540                             ("# bytes in message queue for other peers"),
1541                             msg_size, GNUNET_NO);
1542   mq = GNUNET_malloc (sizeof (struct MessageQueue) + msg_size);
1543   mq->cont = cont;
1544   mq->cont_cls = cont_cls;
1545   /* FIXME: this memcpy can be up to 7% of our total runtime! */
1546   memcpy (&mq[1], msg, msg_size);
1547   mq->message_buf = (const char *) &mq[1];
1548   mq->message_buf_size = msg_size;
1549   mq->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1550   GNUNET_CONTAINER_DLL_insert_tail (n->messages_head, n->messages_tail, mq);
1551
1552   if ((GNUNET_SCHEDULER_NO_TASK == n->transmission_task) &&
1553       (NULL == n->is_active))
1554     n->transmission_task = GNUNET_SCHEDULER_add_now (&transmission_task, n);
1555 }
1556
1557
1558 /**
1559  * We have received a message from the given sender.  How long should
1560  * we delay before receiving more?  (Also used to keep the peer marked
1561  * as live).
1562  *
1563  * @param sender sender of the message
1564  * @param size size of the message
1565  * @param do_forward set to GNUNET_YES if the message should be forwarded to clients
1566  *                   GNUNET_NO if the neighbour is not connected or violates the quota,
1567  *                   GNUNET_SYSERR if the connection is not fully up yet
1568  * @return how long to wait before reading more from this sender
1569  */
1570 struct GNUNET_TIME_Relative
1571 GST_neighbours_calculate_receive_delay (const struct GNUNET_PeerIdentity
1572                                         *sender, ssize_t size, int *do_forward)
1573 {
1574   struct NeighbourMapEntry *n;
1575   struct GNUNET_TIME_Relative ret;
1576
1577   GNUNET_assert (neighbours != NULL);
1578
1579   n = lookup_neighbour (sender);
1580   if (n == NULL)
1581   {
1582     GST_neighbours_try_connect (sender);
1583     n = lookup_neighbour (sender);
1584     if (NULL == n)
1585     {
1586       GNUNET_STATISTICS_update (GST_stats,
1587                                 gettext_noop
1588                                 ("# messages discarded due to lack of neighbour record"),
1589                                 1, GNUNET_NO);
1590       *do_forward = GNUNET_NO;
1591       return GNUNET_TIME_UNIT_ZERO;
1592     }
1593   }
1594   if (!is_connected(n))
1595   {
1596     *do_forward = GNUNET_SYSERR;
1597     return GNUNET_TIME_UNIT_ZERO;
1598   }
1599   if (GNUNET_YES == GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, size))
1600   {
1601     n->quota_violation_count++;
1602 #if DEBUG_TRANSPORT
1603     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1604                 "Bandwidth quota (%u b/s) violation detected (total of %u).\n",
1605                 n->in_tracker.available_bytes_per_s__,
1606                 n->quota_violation_count);
1607 #endif
1608     /* Discount 32k per violation */
1609     GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, -32 * 1024);
1610   }
1611   else
1612   {
1613     if (n->quota_violation_count > 0)
1614     {
1615       /* try to add 32k back */
1616       GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, 32 * 1024);
1617       n->quota_violation_count--;
1618     }
1619   }
1620   if (n->quota_violation_count > QUOTA_VIOLATION_DROP_THRESHOLD)
1621   {
1622     GNUNET_STATISTICS_update (GST_stats,
1623                               gettext_noop
1624                               ("# bandwidth quota violations by other peers"),
1625                               1, GNUNET_NO);
1626     *do_forward = GNUNET_NO;
1627     return GNUNET_CONSTANTS_QUOTA_VIOLATION_TIMEOUT;
1628   }
1629   *do_forward = GNUNET_YES;
1630   ret = GNUNET_BANDWIDTH_tracker_get_delay (&n->in_tracker, 32 * 1024);
1631   if (ret.rel_value > 0)
1632   {
1633 #if DEBUG_TRANSPORT
1634     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1635                 "Throttling read (%llu bytes excess at %u b/s), waiting %llu ms before reading more.\n",
1636                 (unsigned long long) n->in_tracker.
1637                 consumption_since_last_update__,
1638                 (unsigned int) n->in_tracker.available_bytes_per_s__,
1639                 (unsigned long long) ret.rel_value);
1640 #endif
1641     GNUNET_STATISTICS_update (GST_stats,
1642                               gettext_noop ("# ms throttling suggested"),
1643                               (int64_t) ret.rel_value, GNUNET_NO);
1644   }
1645   return ret;
1646 }
1647
1648
1649 /**
1650  * Keep the connection to the given neighbour alive longer,
1651  * we received a KEEPALIVE (or equivalent).
1652  *
1653  * @param neighbour neighbour to keep alive
1654  */
1655 void
1656 GST_neighbours_keepalive (const struct GNUNET_PeerIdentity *neighbour)
1657 {
1658   struct NeighbourMapEntry *n;
1659
1660   GNUNET_assert (neighbours != NULL);
1661
1662   n = lookup_neighbour (neighbour);
1663   if (NULL == n)
1664   {
1665     GNUNET_STATISTICS_update (GST_stats,
1666                               gettext_noop
1667                               ("# KEEPALIVE messages discarded (not connected)"),
1668                               1, GNUNET_NO);
1669     return;
1670   }
1671   GNUNET_SCHEDULER_cancel (n->timeout_task);
1672   n->timeout_task =
1673       GNUNET_SCHEDULER_add_delayed (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
1674                                     &neighbour_timeout_task, n);
1675 }
1676
1677
1678 /**
1679  * Change the incoming quota for the given peer.
1680  *
1681  * @param neighbour identity of peer to change qutoa for
1682  * @param quota new quota
1683  */
1684 void
1685 GST_neighbours_set_incoming_quota (const struct GNUNET_PeerIdentity *neighbour,
1686                                    struct GNUNET_BANDWIDTH_Value32NBO quota)
1687 {
1688   struct NeighbourMapEntry *n;
1689
1690   GNUNET_assert (neighbours != NULL);
1691
1692   n = lookup_neighbour (neighbour);
1693   if (n == NULL)
1694   {
1695     GNUNET_STATISTICS_update (GST_stats,
1696                               gettext_noop
1697                               ("# SET QUOTA messages ignored (no such peer)"),
1698                               1, GNUNET_NO);
1699     return;
1700   }
1701   GNUNET_BANDWIDTH_tracker_update_quota (&n->in_tracker, quota);
1702   if (0 != ntohl (quota.value__))
1703     return;
1704 #if DEBUG_TRANSPORT
1705   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Disconnecting peer `%4s' due to `%s'\n",
1706               GNUNET_i2s (&n->id), "SET_QUOTA");
1707 #endif
1708   if (is_connected(n))
1709     GNUNET_STATISTICS_update (GST_stats,
1710                               gettext_noop ("# disconnects due to quota of 0"), 1,
1711                               GNUNET_NO);
1712   disconnect_neighbour (n);
1713 }
1714
1715
1716 /**
1717  * Closure for the neighbours_iterate function.
1718  */
1719 struct IteratorContext
1720 {
1721   /**
1722    * Function to call on each connected neighbour.
1723    */
1724   GST_NeighbourIterator cb;
1725
1726   /**
1727    * Closure for 'cb'.
1728    */
1729   void *cb_cls;
1730 };
1731
1732
1733 /**
1734  * Call the callback from the closure for each connected neighbour.
1735  *
1736  * @param cls the 'struct IteratorContext'
1737  * @param key the hash of the public key of the neighbour
1738  * @param value the 'struct NeighbourMapEntry'
1739  * @return GNUNET_OK (continue to iterate)
1740  */
1741 static int
1742 neighbours_iterate (void *cls, const GNUNET_HashCode * key, void *value)
1743 {
1744   struct IteratorContext *ic = cls;
1745   struct NeighbourMapEntry *n = value;
1746
1747   if (!is_connected(n))
1748     return GNUNET_OK;
1749
1750   ic->cb (ic->cb_cls, &n->id, NULL, 0, n->plugin_name, n->addr, n->addrlen);
1751   return GNUNET_OK;
1752 }
1753
1754
1755 /**
1756  * Iterate over all connected neighbours.
1757  *
1758  * @param cb function to call
1759  * @param cb_cls closure for cb
1760  */
1761 void
1762 GST_neighbours_iterate (GST_NeighbourIterator cb, void *cb_cls)
1763 {
1764   struct IteratorContext ic;
1765
1766   GNUNET_assert (neighbours != NULL);
1767
1768   ic.cb = cb;
1769   ic.cb_cls = cb_cls;
1770   GNUNET_CONTAINER_multihashmap_iterate (neighbours, &neighbours_iterate, &ic);
1771 }
1772
1773 /**
1774  * If we have an active connection to the given target, it must be shutdown.
1775  *
1776  * @param target peer to disconnect from
1777  */
1778 void
1779 GST_neighbours_force_disconnect (const struct GNUNET_PeerIdentity *target)
1780 {
1781   struct NeighbourMapEntry *n;
1782
1783   GNUNET_assert (neighbours != NULL);
1784
1785   n = lookup_neighbour (target);
1786   if (NULL == n)
1787     return;                     /* not active */
1788   if (is_connected(n))
1789   {
1790     send_disconnect(&n->id, n->plugin_name, n->addr, n->addrlen, n->session);
1791
1792     n = lookup_neighbour (target);
1793     if (NULL == n)
1794       return;                     /* gone already */
1795   }
1796   disconnect_neighbour (n);
1797 }
1798
1799
1800 /**
1801  * We received a disconnect message from the given peer,
1802  * validate and process.
1803  *
1804  * @param peer sender of the message
1805  * @param msg the disconnect message
1806  */
1807 void
1808 GST_neighbours_handle_disconnect_message (const struct GNUNET_PeerIdentity *peer,
1809                                           const struct GNUNET_MessageHeader *msg)
1810 {
1811   struct NeighbourMapEntry *n;
1812   const struct SessionDisconnectMessage *sdm;
1813   GNUNET_HashCode hc;
1814
1815 #if DEBUG_TRANSPORT
1816   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1817       "Received DISCONNECT message from peer `%s'\n", GNUNET_i2s (peer));
1818 #endif
1819
1820   if (ntohs (msg->size) != sizeof (struct SessionDisconnectMessage))
1821   {
1822     // GNUNET_break_op (0);
1823     GNUNET_STATISTICS_update (GST_stats,
1824                               gettext_noop ("# disconnect messages ignored (old format)"), 1,
1825                               GNUNET_NO);
1826     return;
1827   }
1828   sdm = (const struct SessionDisconnectMessage* ) msg;
1829   n = lookup_neighbour (peer);
1830   if (NULL == n)
1831     return;                     /* gone already */
1832   if (GNUNET_TIME_absolute_ntoh (sdm->timestamp).abs_value <=
1833       n->connect_ts.abs_value)
1834   {
1835     GNUNET_STATISTICS_update (GST_stats,
1836                               gettext_noop ("# disconnect messages ignored (timestamp)"), 1,
1837                               GNUNET_NO);
1838     return;
1839   }
1840   GNUNET_CRYPTO_hash (&sdm->public_key,
1841                       sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
1842                       &hc);
1843   if (0 != memcmp (peer,
1844                    &hc,
1845                    sizeof (struct GNUNET_PeerIdentity)))
1846   {
1847     GNUNET_break_op (0);
1848     return;
1849   }
1850   if (ntohl (sdm->purpose.size) !=
1851       sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
1852       sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded) +
1853       sizeof (struct GNUNET_TIME_AbsoluteNBO))
1854   {
1855     GNUNET_break_op (0);
1856     return;
1857   }
1858   if (GNUNET_OK !=
1859       GNUNET_CRYPTO_rsa_verify (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT,
1860                                 &sdm->purpose,
1861                                 &sdm->signature,
1862                                 &sdm->public_key))
1863   {
1864     GNUNET_break_op (0);
1865     return;
1866   }
1867   GST_neighbours_force_disconnect (peer);
1868 }
1869
1870 /**
1871  * We received a 'SESSION_CONNECT_ACK' message from the other peer.
1872  * Consider switching to it.
1873  *
1874  * @param message possibly a 'struct SessionConnectMessage' (check format)
1875  * @param peer identity of the peer to switch the address for
1876  * @param plugin_name name of transport that delivered the PONG
1877  * @param address address of the other peer, NULL if other peer
1878  *                       connected to us
1879  * @param address_len number of bytes in address
1880  * @param session session to use (or NULL)
1881  * @param ats performance data
1882  * @param ats_count number of entries in ats
1883   */
1884 void
1885 GST_neighbours_handle_connect_ack (const struct GNUNET_MessageHeader *message,
1886                                const struct GNUNET_PeerIdentity *peer,
1887                                const char *plugin_name,
1888                                const char *sender_address, uint16_t sender_address_len,
1889                                struct Session *session,
1890                                const struct GNUNET_ATS_Information *ats,
1891                                uint32_t ats_count)
1892 {
1893   const struct SessionConnectMessage *scm;
1894   struct QuotaSetMessage q_msg;
1895   struct GNUNET_MessageHeader msg;
1896   struct NeighbourMapEntry *n;
1897   size_t msg_len;
1898   size_t ret;
1899   int was_connected;
1900
1901 #if DEBUG_TRANSPORT
1902   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1903       "Received CONNECT_ACK message from peer `%s'\n", GNUNET_i2s (peer));
1904 #endif
1905
1906   if (ntohs (message->size) != sizeof (struct SessionConnectMessage))
1907   {
1908     GNUNET_break_op (0);
1909     return;
1910   }
1911
1912   scm = (const struct SessionConnectMessage *) message;
1913   GNUNET_break_op (ntohl (scm->reserved) == 0);
1914   n = lookup_neighbour (peer);
1915   if (NULL == n)
1916     n = setup_neighbour (peer);
1917 /*
1918   if (n->state != S_CONNECT_SENT)
1919   {
1920     GNUNET_break (0);
1921     send_disconnect(&n->id, n->plugin_name, n->addr, n->addrlen, n->session);
1922     return;
1923   }
1924 */
1925   if (NULL != session)
1926     GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1927                      "transport-ats",
1928                      "Giving ATS session %p of plugin %s for peer %s\n",
1929                      session,
1930                      plugin_name,
1931                      GNUNET_i2s (peer));
1932   GNUNET_ATS_address_update (GST_ats,
1933                              peer,
1934                              plugin_name, sender_address, sender_address_len,
1935                              session, ats, ats_count);
1936
1937   was_connected = is_connected(n);
1938   if (!is_connected(n))
1939     change_state (n, S_CONNECTED);
1940
1941 #if DEBUG_TRANSPORT
1942   GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1943               "Setting inbound quota of %u for peer `%s' to \n",
1944               ntohl (n->bandwidth_in.value__), GNUNET_i2s (&n->id));
1945 #endif
1946   GST_neighbours_set_incoming_quota(&n->id, n->bandwidth_in);
1947
1948   /* send ACK (ACK)*/
1949   msg_len =  sizeof (msg);
1950   msg.size = htons (msg_len);
1951   msg.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_ACK);
1952
1953   ret = send_with_plugin (&n->id, (const char *) &msg, msg_len, UINT32_MAX,
1954                           GNUNET_TIME_UNIT_FOREVER_REL,
1955                           n->session, n->plugin_name, n->addr, n->addrlen,
1956                           GNUNET_YES, NULL, NULL);
1957
1958   if (ret == GNUNET_SYSERR)
1959     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1960               "Failed to send SESSION_ACK to `%4s' using plugin `%s' address '%s' session %X\n",
1961               GNUNET_i2s (&n->id), n->plugin_name,
1962               (n->addrlen == 0) ? "<inbound>" : GST_plugins_a2s (n->plugin_name,
1963                                                                  n->addr,
1964                                                                  n->addrlen),
1965               n->session);
1966
1967
1968   if (!was_connected)
1969   {
1970     if (n->keepalive_task == GNUNET_SCHEDULER_NO_TASK)
1971       n->keepalive_task = GNUNET_SCHEDULER_add_delayed (KEEPALIVE_FREQUENCY,
1972                                                         &neighbour_keepalive_task,
1973                                                         n);
1974
1975     neighbours_connected++;
1976     GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# peers connected"), 1,
1977                               GNUNET_NO);
1978 #if DEBUG_TRANSPORT
1979     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1980               "Notify about connect of `%4s' using plugin `%s' address '%s' session %X LINE %u\n",
1981               GNUNET_i2s (&n->id), n->plugin_name,
1982               (n->addrlen == 0) ? "<inbound>" : GST_plugins_a2s (n->plugin_name,
1983                                                                  n->addr,
1984                                                                  n->addrlen),
1985               n->session, __LINE__);
1986 #endif
1987     connect_notify_cb (callback_cls, &n->id, ats, ats_count);
1988   }
1989
1990 #if DEBUG_TRANSPORT
1991     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1992                 "Sending outbound quota of %u Bps for peer `%s' to all clients\n",
1993                 ntohl (n->bandwidth_out.value__), GNUNET_i2s (peer));
1994 #endif
1995     q_msg.header.size = htons (sizeof (struct QuotaSetMessage));
1996     q_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA);
1997     q_msg.quota = n->bandwidth_out;
1998     q_msg.peer = (*peer);
1999     GST_clients_broadcast (&q_msg.header, GNUNET_NO);
2000
2001 }
2002
2003 void
2004 GST_neighbours_handle_ack (const struct GNUNET_MessageHeader *message,
2005     const struct GNUNET_PeerIdentity *peer,
2006     const char *plugin_name,
2007     const char *sender_address, uint16_t sender_address_len,
2008     struct Session *session,
2009     const struct GNUNET_ATS_Information *ats,
2010     uint32_t ats_count)
2011 {
2012   struct NeighbourMapEntry *n;
2013   struct QuotaSetMessage q_msg;
2014   int was_connected;
2015
2016 #if DEBUG_TRANSPORT
2017   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2018       "Received ACK message from peer `%s'\n", GNUNET_i2s (peer));
2019 #endif
2020
2021   if (ntohs (message->size) != sizeof (struct GNUNET_MessageHeader))
2022   {
2023     GNUNET_break_op (0);
2024     return;
2025   }
2026
2027   n = lookup_neighbour (peer);
2028   if (NULL == n)
2029   {
2030     send_disconnect(peer, plugin_name, sender_address, sender_address_len, session);
2031     GNUNET_break (0);
2032   }
2033
2034   if (is_connected(n))
2035     return;
2036
2037   if (NULL != session)
2038     GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
2039                      "transport-ats",
2040                      "Giving ATS session %p of plugin %s for peer %s\n",
2041                      session,
2042                      plugin_name,
2043                      GNUNET_i2s (peer));
2044   GNUNET_ATS_address_update (GST_ats,
2045                              peer,
2046                              plugin_name, sender_address, sender_address_len,
2047                              session, ats, ats_count);
2048
2049   was_connected = is_connected(n);
2050   change_state (n, S_CONNECTED);
2051
2052   GST_neighbours_set_incoming_quota(&n->id, n->bandwidth_in);
2053
2054   if (n->keepalive_task == GNUNET_SCHEDULER_NO_TASK)
2055     n->keepalive_task = GNUNET_SCHEDULER_add_delayed (KEEPALIVE_FREQUENCY,
2056                                                       &neighbour_keepalive_task,
2057                                                       n);
2058
2059   if (!was_connected)
2060   {
2061   neighbours_connected++;
2062   GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# peers connected"), 1,
2063                             GNUNET_NO);
2064
2065 #if DEBUG_TRANSPORT
2066     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2067               "Notify about connect of `%4s' using plugin `%s' address '%s' session %X LINE %u\n",
2068               GNUNET_i2s (&n->id), n->plugin_name,
2069               (n->addrlen == 0) ? "<inbound>" : GST_plugins_a2s (n->plugin_name,
2070                                                                  n->addr,
2071                                                                  n->addrlen),
2072               n->session, __LINE__);
2073 #endif
2074   connect_notify_cb (callback_cls, &n->id, ats, ats_count);
2075   }
2076 #if DEBUG_TRANSPORT
2077   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2078               "Sending outbound quota of %u Bps for peer `%s' to all clients\n",
2079               ntohl (n->bandwidth_out.value__), GNUNET_i2s (peer));
2080 #endif
2081
2082   q_msg.header.size = htons (sizeof (struct QuotaSetMessage));
2083   q_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA);
2084   q_msg.quota = n->bandwidth_out;
2085   q_msg.peer = (*peer);
2086   GST_clients_broadcast (&q_msg.header, GNUNET_NO);
2087
2088 }
2089
2090 struct BlackListCheckContext
2091 {
2092   struct GNUNET_ATS_Information *ats;
2093
2094   uint32_t ats_count;
2095
2096   struct Session *session;
2097
2098   char *sender_address;
2099
2100   uint16_t sender_address_len;
2101
2102   char *plugin_name;
2103
2104   struct GNUNET_TIME_Absolute ts;
2105 };
2106
2107
2108 static void
2109 handle_connect_blacklist_cont (void *cls,
2110                                const struct GNUNET_PeerIdentity
2111                                * peer, int result)
2112 {
2113   struct NeighbourMapEntry *n;
2114   struct BlackListCheckContext * bcc = cls;
2115
2116 #if DEBUG_TRANSPORT
2117   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2118       "Blacklist check due to CONNECT message: `%s'\n", GNUNET_i2s (peer), (result == GNUNET_OK) ? "ALLOWED" : "FORBIDDEN");
2119 #endif
2120
2121   /* not allowed */
2122   if (GNUNET_OK != result)
2123   {
2124     GNUNET_free (bcc);
2125     return;
2126   }
2127
2128   n = lookup_neighbour (peer);
2129   if (NULL == n)
2130     n = setup_neighbour (peer);
2131
2132   if (bcc->ts.abs_value > n->connect_ts.abs_value)
2133   {
2134     if (NULL != bcc->session)
2135       GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
2136                        "transport-ats",
2137                        "Giving ATS session %p of plugin %s address `%s' for peer %s\n",
2138                        bcc->session,
2139                        bcc->plugin_name,
2140                        GST_plugins_a2s (bcc->plugin_name, bcc->sender_address, bcc->sender_address_len),
2141                        GNUNET_i2s (peer));
2142     GNUNET_ATS_address_update (GST_ats,
2143                                peer,
2144                                bcc->plugin_name, bcc->sender_address, bcc->sender_address_len,
2145                                bcc->session, bcc->ats, bcc->ats_count);
2146     n->connect_ts = bcc->ts;
2147   }
2148
2149   GNUNET_free (bcc);
2150 /*
2151   if (n->state != S_NOT_CONNECTED)
2152     return;*/
2153   change_state (n, S_CONNECT_RECV);
2154
2155   /* Ask ATS for an address to connect via that address */
2156   if (n->ats_suggest != GNUNET_SCHEDULER_NO_TASK)
2157     GNUNET_SCHEDULER_cancel(n->ats_suggest);
2158   n->ats_suggest = GNUNET_SCHEDULER_add_delayed (ATS_RESPONSE_TIMEOUT, ats_suggest_cancel, n);
2159   GNUNET_ATS_suggest_address(GST_ats, peer);
2160 }
2161
2162 /**
2163  * We received a 'SESSION_CONNECT' message from the other peer.
2164  * Consider switching to it.
2165  *
2166  * @param message possibly a 'struct SessionConnectMessage' (check format)
2167  * @param peer identity of the peer to switch the address for
2168  * @param plugin_name name of transport that delivered the PONG
2169  * @param address address of the other peer, NULL if other peer
2170  *                       connected to us
2171  * @param address_len number of bytes in address
2172  * @param session session to use (or NULL)
2173  * @param ats performance data
2174  * @param ats_count number of entries in ats (excluding 0-termination)
2175   */
2176 void
2177 GST_neighbours_handle_connect (const struct GNUNET_MessageHeader *message,
2178                                const struct GNUNET_PeerIdentity *peer,
2179                                const char *plugin_name,
2180                                const char *sender_address, uint16_t sender_address_len,
2181                                struct Session *session,
2182                                const struct GNUNET_ATS_Information *ats,
2183                                uint32_t ats_count)
2184 {
2185   const struct SessionConnectMessage *scm;
2186   struct NeighbourMapEntry * n;
2187   struct BlackListCheckContext * bcc = NULL;
2188
2189 #if DEBUG_TRANSPORT
2190   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2191       "Received CONNECT message from peer `%s'\n", GNUNET_i2s (peer));
2192 #endif
2193
2194   if (ntohs (message->size) != sizeof (struct SessionConnectMessage))
2195   {
2196     GNUNET_break_op (0);
2197     return;
2198   }
2199
2200   scm = (const struct SessionConnectMessage *) message;
2201   GNUNET_break_op (ntohl (scm->reserved) == 0);
2202
2203   n = lookup_neighbour(peer);
2204   if (n != NULL)
2205   {
2206     /* connected peer switches addresses */
2207     if (is_connected(n))
2208     {
2209       GNUNET_ATS_address_update(GST_ats, peer, plugin_name, sender_address, sender_address_len, session, ats, ats_count);
2210       return;
2211     }
2212   }
2213
2214   /* we are not connected to this peer */
2215   /* do blacklist check*/
2216   bcc = GNUNET_malloc (sizeof (struct BlackListCheckContext) +
2217             sizeof (struct GNUNET_ATS_Information) * ats_count +
2218             sender_address_len +
2219             strlen (plugin_name)+1);
2220
2221   bcc->ts = GNUNET_TIME_absolute_ntoh (scm->timestamp);
2222
2223   bcc->ats_count = ats_count;
2224   bcc->sender_address_len = sender_address_len;
2225   bcc->session = session;
2226
2227   bcc->ats = (struct GNUNET_ATS_Information *) &bcc[1];
2228   memcpy (bcc->ats, ats,sizeof (struct GNUNET_ATS_Information) * ats_count );
2229
2230   bcc->sender_address = (char *) &bcc->ats[ats_count];
2231   memcpy (bcc->sender_address, sender_address , sender_address_len);
2232
2233   bcc->plugin_name = &bcc->sender_address[sender_address_len];
2234   strcpy (bcc->plugin_name, plugin_name);
2235
2236   GST_blacklist_test_allowed (peer, plugin_name, handle_connect_blacklist_cont, bcc);
2237 }
2238
2239
2240 /* end of file gnunet-service-transport_neighbours.c */