src/transport/gnunet-service-transport_neighbours.c

   1 /*
   2      This file is part of GNUnet.
   3      (C) 2010-2013 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 /**
  41  * Size of the neighbour hash map.
  42  */
  43 #define NEIGHBOUR_TABLE_SIZE 256
  44
  45 /**
  46  * Time we give plugin to transmit DISCONNECT message before the
  47  * neighbour entry self-destructs.
  48  */
  49 #define DISCONNECT_SENT_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, 100)
  50
  51 /**
  52  * How often must a peer violate bandwidth quotas before we start
  53  * to simply drop its messages?
  54  */
  55 #define QUOTA_VIOLATION_DROP_THRESHOLD 10
  56
  57 /**
  58  * How long are we willing to wait for a response from ATS before timing out?
  59  */
  60 #define ATS_RESPONSE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, 5000)
  61
  62 /**
  63  * How long are we willing to wait for an ACK from the other peer before
  64  * giving up on our connect operation?
  65  */
  66 #define SETUP_CONNECTION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
  67
  68 /**
  69  * How long are we willing to wait for a successful reconnect if
  70  * an existing connection went down?  Much shorter than the
  71  * usual SETUP_CONNECTION_TIMEOUT as we do not inform the
  72  * higher layers about the disconnect during this period.
  73  */
  74 #define FAST_RECONNECT_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
  75
  76 /**
  77  * How long are we willing to wait for a response from the blacklist
  78  * subsystem before timing out?
  79  */
  80 #define BLACKLIST_RESPONSE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, 500)
  81
  82 /**
  83  * Interval to send utilization data
  84  */
  85 #define UTIL_TRANSMISSION_INTERVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
  86
  87 GNUNET_NETWORK_STRUCT_BEGIN
  88
  89 /**
  90  * Message a peer sends to another to indicate that it intends to
  91  * setup a connection/session for data exchange.  A 'SESSION_CONNECT'
  92  * should be answered with a 'SESSION_CONNECT_ACK' with the same body
  93  * to confirm.  A 'SESSION_CONNECT_ACK' should then be followed with
  94  * a 'SESSION_ACK'.  Once the 'SESSION_ACK' is received, both peers
  95  * should be connected.
  96  */
  97 struct SessionConnectMessage
  98 {
  99   /**
 100    * Header of type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_CONNECT
 101    * or #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_CONNECT_ACK
 102    */
 103   struct GNUNET_MessageHeader header;
 104
 105   /**
 106    * Always zero.
 107    */
 108   uint32_t reserved GNUNET_PACKED;
 109
 110   /**
 111    * Absolute time at the sender.  Only the most recent connect
 112    * message implies which session is preferred by the sender.
 113    */
 114   struct GNUNET_TIME_AbsoluteNBO timestamp;
 115
 116 };
 117
 118
 119 /**
 120  * Message a peer sends to another when connected to indicate that a
 121  * session is in use and the peer is still alive or to respond to a keep alive.
 122  * A peer sends a message with type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE
 123  * to request a message with #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE_RESPONSE.
 124  * When the keep alive response with type is received, transport service
 125  * will call the respective plugin to update the session timeout
 126  */
 127 struct SessionKeepAliveMessage
 128 {
 129   /**
 130    * Header of type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE or
 131    * #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE_RESPONSE.
 132    */
 133   struct GNUNET_MessageHeader header;
 134
 135   /**
 136    * A nonce to identify the session the keep alive is used for
 137    */
 138   uint32_t nonce GNUNET_PACKED;
 139 };
 140
 141 /**
 142  * Message we send to the other peer to notify him that we intentionally
 143  * are disconnecting (to reduce timeouts).  This is just a friendly
 144  * notification, peers must not rely on always receiving disconnect
 145  * messages.
 146  */
 147 struct SessionDisconnectMessage
 148 {
 149   /**
 150    * Header of type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT
 151    */
 152   struct GNUNET_MessageHeader header;
 153
 154   /**
 155    * Always zero.
 156    */
 157   uint32_t reserved GNUNET_PACKED;
 158
 159   /**
 160    * Purpose of the signature.  Extends over the timestamp.
 161    * Purpose should be #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DISCONNECT.
 162    */
 163   struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
 164
 165   /**
 166    * Absolute time at the sender.  Only the most recent connect
 167    * message implies which session is preferred by the sender.
 168    */
 169   struct GNUNET_TIME_AbsoluteNBO timestamp;
 170
 171   /**
 172    * Public key of the sender.
 173    */
 174   struct GNUNET_CRYPTO_EddsaPublicKey public_key;
 175
 176   /**
 177    * Signature of the peer that sends us the disconnect.  Only
 178    * valid if the timestamp is AFTER the timestamp from the
 179    * corresponding 'CONNECT' message.
 180    */
 181   struct GNUNET_CRYPTO_EddsaSignature signature;
 182
 183 };
 184
 185 GNUNET_NETWORK_STRUCT_END
 186
 187
 188 /**
 189  * For each neighbour we keep a list of messages
 190  * that we still want to transmit to the neighbour.
 191  */
 192 struct MessageQueue
 193 {
 194
 195   /**
 196    * This is a doubly linked list.
 197    */
 198   struct MessageQueue *next;
 199
 200   /**
 201    * This is a doubly linked list.
 202    */
 203   struct MessageQueue *prev;
 204
 205   /**
 206    * Function to call once we're done.
 207    */
 208   GST_NeighbourSendContinuation cont;
 209
 210   /**
 211    * Closure for @e cont
 212    */
 213   void *cont_cls;
 214
 215   /**
 216    * The message(s) we want to transmit, GNUNET_MessageHeader(s)
 217    * stuck together in memory.  Allocated at the end of this struct.
 218    */
 219   const char *message_buf;
 220
 221   /**
 222    * Size of the message buf
 223    */
 224   size_t message_buf_size;
 225
 226   /**
 227    * At what time should we fail?
 228    */
 229   struct GNUNET_TIME_Absolute timeout;
 230
 231 };
 232
 233
 234
 235
 236 /**
 237  * A possible address we could use to communicate with a neighbour.
 238  */
 239 struct NeighbourAddress
 240 {
 241
 242   /**
 243    * Active session for this address.
 244    */
 245   struct Session *session;
 246
 247   /**
 248    * Network-level address information.
 249    */
 250   struct GNUNET_HELLO_Address *address;
 251
 252   /**
 253    * Timestamp of the 'SESSION_CONNECT' message we sent to the other
 254    * peer for this address.  Use to check that the ACK is in response
 255    * to our most recent 'CONNECT'.
 256    */
 257   struct GNUNET_TIME_Absolute connect_timestamp;
 258
 259   /**
 260    * Inbound bandwidth from ATS for this address.
 261    */
 262   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in;
 263
 264   /**
 265    * Outbound bandwidth from ATS for this address.
 266    */
 267   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out;
 268
 269   /**
 270    * Did we tell ATS that this is our 'active' address?
 271    */
 272   int ats_active;
 273
 274   /**
 275    * The current nonce sent in the last keep alive messages
 276    */
 277   uint32_t keep_alive_nonce;
 278 };
 279
 280
 281 /**
 282  * Entry in neighbours.
 283  */
 284 struct NeighbourMapEntry
 285 {
 286
 287   /**
 288    * Head of list of messages we would like to send to this peer;
 289    * must contain at most one message per client.
 290    */
 291   struct MessageQueue *messages_head;
 292
 293   /**
 294    * Tail of list of messages we would like to send to this peer; must
 295    * contain at most one message per client.
 296    */
 297   struct MessageQueue *messages_tail;
 298
 299   /**
 300    * Are we currently trying to send a message? If so, which one?
 301    */
 302   struct MessageQueue *is_active;
 303
 304   /**
 305    * Primary address we currently use to communicate with the neighbour.
 306    */
 307   struct NeighbourAddress primary_address;
 308
 309   /**
 310    * Alternative address currently under consideration for communicating
 311    * with the neighbour.
 312    */
 313   struct NeighbourAddress alternative_address;
 314
 315   /**
 316    * Identity of this neighbour.
 317    */
 318   struct GNUNET_PeerIdentity id;
 319
 320   /**
 321    * Main task that drives this peer (timeouts, keepalives, etc.).
 322    * Always runs the 'master_task'.
 323    */
 324   GNUNET_SCHEDULER_TaskIdentifier task;
 325
 326   /**
 327    * At what time should we sent the next keep-alive message?
 328    */
 329   struct GNUNET_TIME_Absolute keep_alive_time;
 330
 331   /**
 332    * At what time did we sent the last keep-alive message?  Used
 333    * to calculate round-trip time ("latency").
 334    */
 335   struct GNUNET_TIME_Absolute last_keep_alive_time;
 336
 337   /**
 338    * Timestamp we should include in our next CONNECT_ACK message.
 339    * (only valid if 'send_connect_ack' is #GNUNET_YES).  Used to build
 340    * our CONNECT_ACK message.
 341    */
 342   struct GNUNET_TIME_Absolute connect_ack_timestamp;
 343
 344   /**
 345    * ATS address suggest handle
 346    */
 347   struct GNUNET_ATS_SuggestHandle *suggest_handle;
 348
 349   /**
 350    * Time where we should cut the connection (timeout) if we don't
 351    * make progress in the state machine (or get a KEEPALIVE_RESPONSE
 352    * if we are in S_CONNECTED).
 353    */
 354   struct GNUNET_TIME_Absolute timeout;
 355
 356   /**
 357    * Latest calculated latency value
 358    */
 359   struct GNUNET_TIME_Relative latency;
 360
 361   /**
 362    * Tracker for inbound bandwidth.
 363    */
 364   struct GNUNET_BANDWIDTH_Tracker in_tracker;
 365
 366   /**
 367    * How often has the other peer (recently) violated the inbound
 368    * traffic limit?  Incremented by 10 per violation, decremented by 1
 369    * per non-violation (for each time interval).
 370    */
 371   unsigned int quota_violation_count;
 372
 373   /**
 374    * The current state of the peer.
 375    */
 376   enum GNUNET_TRANSPORT_PeerState state;
 377
 378   /**
 379    * Did we sent an KEEP_ALIVE message and are we expecting a response?
 380    */
 381   int expect_latency_response;
 382
 383   /**
 384    * Flag to set if we still need to send a CONNECT_ACK message to the other peer
 385    * (once we have an address to use and the peer has been allowed by our
 386    * blacklist).  Set to 1 if we need to send a CONNECT_ACK.  Set to 2 if we
 387    * did send a CONNECT_ACK and should go to 'S_CONNECTED' upon receiving
 388    * a 'SESSION_ACK' (regardless of what our own state machine might say).
 389    */
 390   int send_connect_ack;
 391
 392   /**
 393    * Tracking utilization of outbound bandwidth
 394    */
 395   uint32_t util_payload_bytes_sent;
 396
 397   /**
 398    * Tracking utilization of inbound bandwidth
 399    */
 400   uint32_t util_payload_bytes_recv;
 401
 402   /**
 403    * Tracking utilization of outbound bandwidth
 404    */
 405   uint32_t util_total_bytes_sent;
 406
 407   /**
 408    * Tracking utilization of inbound bandwidth
 409    */
 410   uint32_t util_total_bytes_recv;
 411
 412   /**
 413    * Date of last utilization transmission
 414    */
 415   struct GNUNET_TIME_Absolute last_util_transmission;
 416 };
 417
 418
 419 /**
 420  * Context for blacklist checks and the #handle_test_blacklist_cont()
 421  * function.  Stores information about ongoing blacklist checks.
 422  */
 423 struct BlackListCheckContext
 424 {
 425
 426   /**
 427    * We keep blacklist checks in a DLL.
 428    */
 429   struct BlackListCheckContext *next;
 430
 431   /**
 432    * We keep blacklist checks in a DLL.
 433    */
 434   struct BlackListCheckContext *prev;
 435
 436   /**
 437    * Address that is being checked.
 438    */
 439   struct NeighbourAddress na;
 440
 441   /**
 442    * Handle to the ongoing blacklist check.
 443    */
 444   struct GST_BlacklistCheck *bc;
 445 };
 446
 447
 448 /**
 449  * Hash map from peer identities to the respective 'struct NeighbourMapEntry'.
 450  */
 451 static struct GNUNET_CONTAINER_MultiPeerMap *neighbours;
 452
 453 /**
 454  * We keep blacklist checks in a DLL so that we can find
 455  * the 'sessions' in their 'struct NeighbourAddress' if
 456  * a session goes down.
 457  */
 458 static struct BlackListCheckContext *bc_head;
 459
 460 /**
 461  * We keep blacklist checks in a DLL.
 462  */
 463 static struct BlackListCheckContext *bc_tail;
 464
 465 /**
 466  * List of pending blacklist checks: head
 467  */
 468 static struct BlacklistCheckSwitchContext *pending_bc_head;
 469
 470 /**
 471  * List of pending blacklist checks: tail
 472  */
 473 static struct BlacklistCheckSwitchContext *pending_bc_tail;
 474
 475 /**
 476  * Closure for #connect_notify_cb, #disconnect_notify_cb and #neighbour_change_cb
 477  */
 478 static void *callback_cls;
 479
 480 /**
 481  * Function to call when we connected to a neighbour.
 482  */
 483 static NotifyConnect connect_notify_cb;
 484
 485 /**
 486  * Function to call when we disconnected from a neighbour.
 487  */
 488 static GNUNET_TRANSPORT_NotifyDisconnect disconnect_notify_cb;
 489
 490 /**
 491  * Function to call when a neighbour changed address, state or bandwidth.
 492  */
 493 static GNUNET_TRANSPORT_NeighbourChangeCallback neighbour_change_cb;
 494
 495 /**
 496  * counter for connected neighbours
 497  */
 498 static unsigned int neighbours_connected;
 499
 500 /**
 501  * Number of bytes we have currently queued for transmission.
 502  */
 503 static unsigned long long bytes_in_send_queue;
 504
 505 /**
 506  * Task transmitting utilization data
 507  */
 508 static GNUNET_SCHEDULER_TaskIdentifier util_transmission_tk;
 509
 510
 511 static struct GNUNET_CONTAINER_MultiPeerMap *registered_quota_notifications;
 512
 513 /**
 514  * Lookup a neighbour entry in the neighbours hash map.
 515  *
 516  * @param pid identity of the peer to look up
 517  * @return the entry, NULL if there is no existing record
 518  */
 519 static struct NeighbourMapEntry *
 520 lookup_neighbour (const struct GNUNET_PeerIdentity *pid)
 521 {
 522   if (NULL == neighbours)
 523     return NULL;
 524   return GNUNET_CONTAINER_multipeermap_get (neighbours, pid);
 525 }
 526
 527
 528 /**
 529  * Test if we're connected to the given peer.
 530  *
 531  * @param n neighbour entry of peer to test
 532  * @return #GNUNET_YES if we are connected, #GNUNET_NO if not
 533  */
 534 static int
 535 test_connected (struct NeighbourMapEntry *n)
 536 {
 537   if (NULL == n)
 538     return GNUNET_NO;
 539   return GNUNET_TRANSPORT_is_connected (n->state);
 540 }
 541
 542 /**
 543  * Send information about a new outbound quota to our clients.
 544  *
 545  * @param target affected peer
 546  * @param quota new quota
 547  */
 548 static void
 549 send_outbound_quota (const struct GNUNET_PeerIdentity *target,
 550                      struct GNUNET_BANDWIDTH_Value32NBO quota)
 551 {
 552   struct QuotaSetMessage q_msg;
 553
 554   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 555               "Sending outbound quota of %u Bps for peer `%s' to all clients\n",
 556               ntohl (quota.value__), GNUNET_i2s (target));
 557   q_msg.header.size = htons (sizeof (struct QuotaSetMessage));
 558   q_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA);
 559   q_msg.quota = quota;
 560   q_msg.peer = (*target);
 561   GST_clients_broadcast (&q_msg.header, GNUNET_NO);
 562 }
 563
 564
 565 /**
 566  * We don't need a given neighbour address any more.
 567  * Release its resources and give appropriate notifications
 568  * to ATS and other subsystems.
 569  *
 570  * @param na address we are done with; @a na itself must NOT be 'free'd, only the contents!
 571  */
 572 static void
 573 free_address (struct NeighbourAddress *na)
 574 {
 575   if (GNUNET_YES == na->ats_active)
 576   {
 577     GST_validation_set_address_use (na->address, na->session, GNUNET_NO);
 578     GNUNET_ATS_address_in_use (GST_ats, na->address, na->session, GNUNET_NO);
 579   }
 580
 581   na->ats_active = GNUNET_NO;
 582   na->keep_alive_nonce = 0;
 583   if (NULL != na->address)
 584   {
 585     GNUNET_HELLO_address_free (na->address);
 586     na->address = NULL;
 587   }
 588   na->session = NULL;
 589 }
 590
 591
 592 /**
 593  * Set net state for this neighbour and notify monitoring
 594  *
 595  * @param n the respective neighbour
 596  * @param s the new state
 597  */
 598 static void
 599 set_state (struct NeighbourMapEntry *n, enum GNUNET_TRANSPORT_PeerState s)
 600 {
 601   n->state = s;
 602   GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Neighbour `%s' changed state to %s\n",
 603       GNUNET_i2s (&n->id),
 604       GNUNET_TRANSPORT_ps2s(s));
 605   neighbour_change_cb (callback_cls,
 606       &n->id,
 607       n->primary_address.address,
 608       n->state, n->timeout,
 609       n->primary_address.bandwidth_in,
 610       n->primary_address.bandwidth_out);
 611
 612 }
 613
 614 /**
 615  * Set net state and state timeout for this neighbour and notify monitoring
 616  *
 617  * @param n the respective neighbour
 618  * @param s the new state
 619  * @param timeout the new timeout
 620  */
 621 static void
 622 set_state_and_timeout (struct NeighbourMapEntry *n,
 623     enum GNUNET_TRANSPORT_PeerState s,
 624     struct GNUNET_TIME_Absolute timeout)
 625 {
 626   n->state = s;
 627   n->timeout = timeout;
 628   GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Neighbour `%s' changed state to %s with timeout %s\n",
 629       GNUNET_i2s (&n->id),
 630       GNUNET_TRANSPORT_ps2s(s),
 631       GNUNET_STRINGS_absolute_time_to_string (timeout));
 632   neighbour_change_cb (callback_cls,
 633       &n->id,
 634       n->primary_address.address,
 635       n->state, n->timeout,
 636       n->primary_address.bandwidth_in,
 637       n->primary_address.bandwidth_out);
 638 }
 639
 640
 641 /**
 642  * Set new state timeout for this neighbour and notify monitoring
 643  *
 644  * @param n the respective neighbour
 645  * @param timeout the new timeout
 646  */
 647 static void
 648 set_timeout (struct NeighbourMapEntry *n,
 649     struct GNUNET_TIME_Absolute timeout)
 650 {
 651   n->timeout = timeout;
 652   GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Neighbour `%s' changed timeout %s\n",
 653       GNUNET_i2s (&n->id),
 654       GNUNET_STRINGS_absolute_time_to_string (timeout));
 655   neighbour_change_cb (callback_cls,
 656       &n->id,
 657       n->primary_address.address,
 658       n->state, n->timeout,
 659       n->primary_address.bandwidth_in,
 660       n->primary_address.bandwidth_out);
 661 }
 662
 663
 664 /**
 665  * Initialize the alternative address of a neighbour
 666  *
 667  * @param n the neighbour
 668  * @param address address of the other peer, NULL if other peer
 669  *                       connected to us
 670  * @param session session to use (or NULL, in which case an
 671  *        address must be setup)
 672  * @param bandwidth_in inbound quota to be used when connection is up
 673  * @param bandwidth_out outbound quota to be used when connection is up
 674  */
 675 static void
 676 set_alternative_address (struct NeighbourMapEntry *n,
 677              const struct GNUNET_HELLO_Address *address,
 678              struct Session *session,
 679              struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
 680              struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
 681 {
 682   struct GNUNET_TRANSPORT_PluginFunctions *papi;
 683   if (NULL == (papi = GST_plugins_find (address->transport_name)))
 684   {
 685     GNUNET_break (0);
 686     return;
 687   }
 688   if (session == n->alternative_address.session)
 689   {
 690     n->alternative_address.bandwidth_in = bandwidth_in;
 691     n->alternative_address.bandwidth_out = bandwidth_out;
 692     return;
 693   }
 694   free_address (&n->alternative_address);
 695   if (NULL == session)
 696     session = papi->get_session (papi->cls, address);
 697   if (NULL == session)
 698   {
 699     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 700                 "Failed to obtain new session for peer `%s' and  address '%s'\n",
 701                 GNUNET_i2s (&address->peer), GST_plugins_a2s (address));
 702     GNUNET_ATS_address_destroyed (GST_ats, address, NULL);
 703     return;
 704   }
 705
 706   GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Neighbour `%s' configured alternative address %s\n",
 707       GNUNET_i2s (&n->id),
 708       GST_plugins_a2s(address));
 709
 710   n->alternative_address.address = GNUNET_HELLO_address_copy (address);
 711   n->alternative_address.bandwidth_in = bandwidth_in;
 712   n->alternative_address.bandwidth_out = bandwidth_out;
 713   n->alternative_address.session = session;
 714   n->alternative_address.ats_active = GNUNET_NO;
 715   n->alternative_address.keep_alive_nonce = 0;
 716 }
 717
 718
 719 /**
 720  * Initialize the primary address of a neighbour
 721  *
 722  * @param n the neighbour
 723  * @param address address of the other peer, NULL if other peer
 724  *                       connected to us
 725  * @param session session to use (or NULL, in which case an
 726  *        address must be setup)
 727  * @param bandwidth_in inbound quota to be used when connection is up
 728  * @param bandwidth_out outbound quota to be used when connection is up
 729  * @param is_active #GNUNET_YES to mark this as the active address with ATS
 730  */
 731 static void
 732 set_primary_address (struct NeighbourMapEntry *n,
 733              const struct GNUNET_HELLO_Address *address,
 734              struct Session *session,
 735              struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
 736              struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out,
 737              int is_active)
 738 {
 739   struct GNUNET_TRANSPORT_PluginFunctions *papi;
 740
 741   if (NULL == (papi = GST_plugins_find (address->transport_name)))
 742   {
 743     GNUNET_break (0);
 744     return;
 745   }
 746   if (session == n->primary_address.session)
 747   {
 748     n->primary_address.bandwidth_in = bandwidth_in;
 749     n->primary_address.bandwidth_out = bandwidth_out;
 750     if (is_active != n->primary_address.ats_active)
 751     {
 752       n->primary_address.ats_active = is_active;
 753       GNUNET_ATS_address_in_use (GST_ats, n->primary_address.address, n->primary_address.session, is_active);
 754       GST_validation_set_address_use (n->primary_address.address, n->primary_address.session, is_active);
 755     }
 756     if (GNUNET_YES == is_active)
 757     {
 758       GST_neighbours_set_incoming_quota (&address->peer, bandwidth_in);
 759       send_outbound_quota (&address->peer, bandwidth_out);
 760     }
 761     return;
 762   }
 763   free_address (&n->primary_address);
 764   if (NULL == session)
 765     session = papi->get_session (papi->cls, address);
 766   if (NULL == session)
 767   {
 768     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 769                 "Failed to obtain new session for peer `%s' and  address '%s'\n",
 770                 GNUNET_i2s (&address->peer), GST_plugins_a2s (address));
 771     GNUNET_ATS_address_destroyed (GST_ats, address, NULL);
 772     return;
 773   }
 774
 775   n->primary_address.address = GNUNET_HELLO_address_copy (address);
 776   n->primary_address.bandwidth_in = bandwidth_in;
 777   n->primary_address.bandwidth_out = bandwidth_out;
 778   n->primary_address.session = session;
 779   n->primary_address.ats_active = is_active;
 780   n->primary_address.keep_alive_nonce = 0;
 781   if (GNUNET_YES == is_active)
 782   {
 783     /* Telling ATS about new session */
 784     GNUNET_ATS_address_in_use (GST_ats, n->primary_address.address, n->primary_address.session, GNUNET_YES);
 785     GST_validation_set_address_use (n->primary_address.address, n->primary_address.session, GNUNET_YES);
 786     GST_neighbours_set_incoming_quota (&address->peer, bandwidth_in);
 787     send_outbound_quota (&address->peer, bandwidth_out);
 788   }
 789
 790   GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Neighbour `%s' switched to address `%s'\n",
 791       GNUNET_i2s (&n->id),
 792       GST_plugins_a2s(address));
 793
 794   neighbour_change_cb (callback_cls,
 795       &n->id,
 796       n->primary_address.address,
 797       n->state, n->timeout,
 798       n->primary_address.bandwidth_in,
 799       n->primary_address.bandwidth_out);
 800 }
 801
 802 #if 0
 803 TODO: Implement this
 804 /**
 805  * Clear the primary address of a neighbour since this primary address is not
 806  * valid anymore and notify monitoring about it
 807  *
 808  * @param n the neighbour
 809  */
 810 static void
 811 unset_primary_address (struct NeighbourMapEntry *n)
 812 {
 813
 814 }
 815
 816 #endif
 817
 818
 819 /**
 820  * Free a neighbour map entry.
 821  *
 822  * @param n entry to free
 823  * @param keep_sessions #GNUNET_NO to tell plugin to terminate sessions,
 824  *                      #GNUNET_YES to keep all sessions
 825  */
 826 static void
 827 free_neighbour (struct NeighbourMapEntry *n,
 828                 int keep_sessions)
 829 {
 830   struct MessageQueue *mq;
 831   struct GNUNET_TRANSPORT_PluginFunctions *papi;
 832   struct GNUNET_HELLO_Address *backup_primary;
 833
 834   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 835               "Freeing neighbur state of peer `%s'\n",
 836               GNUNET_i2s (&n->id));
 837   n->is_active = NULL; /* always free'd by its own continuation! */
 838
 839   /* fail messages currently in the queue */
 840   while (NULL != (mq = n->messages_head))
 841   {
 842     GNUNET_CONTAINER_DLL_remove (n->messages_head, n->messages_tail, mq);
 843     if (NULL != mq->cont)
 844       mq->cont (mq->cont_cls, GNUNET_SYSERR, mq->message_buf_size, 0);
 845     GNUNET_free (mq);
 846   }
 847   /* It is too late to send other peer disconnect notifications, but at
 848      least internally we need to get clean... */
 849   if (GNUNET_YES == test_connected (n))
 850   {
 851     GNUNET_STATISTICS_set (GST_stats,
 852                            gettext_noop ("# peers connected"),
 853                            --neighbours_connected,
 854                            GNUNET_NO);
 855     disconnect_notify_cb (callback_cls, &n->id);
 856   }
 857   set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED);
 858
 859   if (NULL != n->primary_address.address)
 860   {
 861     backup_primary = GNUNET_HELLO_address_copy (n->primary_address.address);
 862   }
 863   else
 864     backup_primary = NULL;
 865
 866   /* free addresses and mark as unused */
 867   free_address (&n->primary_address);
 868   free_address (&n->alternative_address);
 869
 870   /* FIXME: Note that if we are switching between two TCP sessions to
 871      the same peer, we might want to selectively kill only one of
 872      them! Killing all sessions like this seems to be very, very
 873      wrong. */
 874
 875   /* cut transport-level connection */
 876   if ((GNUNET_NO == keep_sessions) &&
 877       (NULL != backup_primary) &&
 878       (NULL != (papi = GST_plugins_find (backup_primary->transport_name))))
 879     papi->disconnect_peer (papi->cls, &n->id);
 880
 881   GNUNET_free_non_null (backup_primary);
 882
 883   GNUNET_assert (GNUNET_YES ==
 884                  GNUNET_CONTAINER_multipeermap_remove (neighbours,
 885                                                        &n->id, n));
 886
 887   // FIXME-ATS-API: we might want to be more specific about
 888   // which states we do this from in the future (ATS should
 889   // have given us a 'suggest_address' handle, and if we have
 890   // such a handle, we should cancel the operation here!
 891   if (NULL != n->suggest_handle)
 892   {
 893     GNUNET_ATS_suggest_address_cancel (GST_ats, &n->id);
 894     n->suggest_handle = NULL;
 895   }
 896
 897   if (GNUNET_SCHEDULER_NO_TASK != n->task)
 898   {
 899     GNUNET_SCHEDULER_cancel (n->task);
 900     n->task = GNUNET_SCHEDULER_NO_TASK;
 901   }
 902   /* free rest of memory */
 903   GNUNET_free (n);
 904 }
 905
 906
 907 /**
 908  * Transmit a message using the current session of the given
 909  * neighbour.
 910  *
 911  * @param n entry for the recipient
 912  * @param msgbuf buffer to transmit
 913  * @param msgbuf_size number of bytes in @a msgbuf buffer
 914  * @param priority transmission priority
 915  * @param timeout transmission timeout
 916  * @param use_keepalive_timeout #GNUNET_YES to use plugin-specific keep-alive
 917  *        timeout (@a timeout is ignored in that case), #GNUNET_NO otherwise
 918  * @param cont continuation to call when finished (can be NULL)
 919  * @param cont_cls closure for @a cont
 920  * @return timeout (copy of @a timeout or a calculated one if
 921  *         @a use_keepalive_timeout is #GNUNET_YES.
 922  */
 923 static struct GNUNET_TIME_Relative
 924 send_with_session (struct NeighbourMapEntry *n,
 925                    const char *msgbuf, size_t msgbuf_size,
 926                    uint32_t priority,
 927                    struct GNUNET_TIME_Relative timeout,
 928                    unsigned int use_keepalive_timeout,
 929                    GNUNET_TRANSPORT_TransmitContinuation cont,
 930                    void *cont_cls)
 931 {
 932   struct GNUNET_TRANSPORT_PluginFunctions *papi;
 933   struct GNUNET_TIME_Relative result = GNUNET_TIME_UNIT_FOREVER_REL;
 934
 935   GNUNET_assert (n->primary_address.session != NULL);
 936   if ( ((NULL == (papi = GST_plugins_find (n->primary_address.address->transport_name)) ||
 937          (-1 == papi->send (papi->cls,
 938                             n->primary_address.session,
 939                             msgbuf, msgbuf_size,
 940                             priority,
 941                             (result = (GNUNET_NO == use_keepalive_timeout) ? timeout :
 942                                 GNUNET_TIME_relative_divide (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
 943                                                              papi->query_keepalive_factor (papi->cls))),
 944                             cont, cont_cls)))) &&
 945        (NULL != cont))
 946     cont (cont_cls, &n->id, GNUNET_SYSERR, msgbuf_size, 0);
 947   GST_neighbours_notify_data_sent (&n->id,
 948       n->primary_address.address, n->primary_address.session, msgbuf_size);
 949   GNUNET_break (NULL != papi);
 950   return result;
 951 }
 952
 953
 954 /**
 955  * Master task run for every neighbour.  Performs all of the time-related
 956  * activities (keep alive, send next message, disconnect if idle, finish
 957  * clean up after disconnect).
 958  *
 959  * @param cls the `struct NeighbourMapEntry` for which we are running
 960  * @param tc scheduler context (unused)
 961  */
 962 static void
 963 master_task (void *cls,
 964              const struct GNUNET_SCHEDULER_TaskContext *tc);
 965
 966
 967 /**
 968  * Function called when the 'DISCONNECT' message has been sent by the
 969  * plugin.  Frees the neighbour --- if the entry still exists.
 970  *
 971  * @param cls NULL
 972  * @param target identity of the neighbour that was disconnected
 973  * @param result #GNUNET_OK if the disconnect got out successfully
 974  * @param payload bytes payload
 975  * @param physical bytes physical
 976  */
 977 static void
 978 send_disconnect_cont (void *cls, const struct GNUNET_PeerIdentity *target,
 979                       int result, size_t payload, size_t physical)
 980 {
 981   struct NeighbourMapEntry *n;
 982
 983   n = lookup_neighbour (target);
 984   if (NULL == n)
 985     return; /* already gone */
 986   if (GNUNET_TRANSPORT_PS_DISCONNECT != n->state)
 987     return; /* have created a fresh entry since */
 988   if (GNUNET_SCHEDULER_NO_TASK != n->task)
 989     GNUNET_SCHEDULER_cancel (n->task);
 990   n->task = GNUNET_SCHEDULER_add_now (&master_task, n);
 991 }
 992
 993
 994 /**
 995  * Transmit a DISCONNECT message to the other peer.
 996  *
 997  * @param n neighbour to send DISCONNECT message.
 998  */
 999 static void
1000 send_disconnect (struct NeighbourMapEntry *n)
1001 {
1002   struct SessionDisconnectMessage disconnect_msg;
1003
1004   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1005               "Sending DISCONNECT message to peer `%4s'\n",
1006               GNUNET_i2s (&n->id));
1007   disconnect_msg.header.size = htons (sizeof (struct SessionDisconnectMessage));
1008   disconnect_msg.header.type =
1009       htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT);
1010   disconnect_msg.reserved = htonl (0);
1011   disconnect_msg.purpose.size =
1012       htonl (sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
1013              sizeof (struct GNUNET_CRYPTO_EddsaPublicKey) +
1014              sizeof (struct GNUNET_TIME_AbsoluteNBO));
1015   disconnect_msg.purpose.purpose =
1016       htonl (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT);
1017   disconnect_msg.timestamp =
1018       GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ());
1019   disconnect_msg.public_key = GST_my_identity.public_key;
1020   GNUNET_assert (GNUNET_OK ==
1021                  GNUNET_CRYPTO_eddsa_sign (GST_my_private_key,
1022                                          &disconnect_msg.purpose,
1023                                          &disconnect_msg.signature));
1024
1025   (void) send_with_session (n,
1026                             (const char *) &disconnect_msg, sizeof (disconnect_msg),
1027                             UINT32_MAX, GNUNET_TIME_UNIT_FOREVER_REL,
1028                             GNUNET_NO, &send_disconnect_cont, NULL);
1029   GNUNET_STATISTICS_update (GST_stats,
1030                             gettext_noop
1031                             ("# DISCONNECT messages sent"), 1,
1032                             GNUNET_NO);
1033 }
1034
1035
1036 /**
1037  * Disconnect from the given neighbour, clean up the record.
1038  *
1039  * @param n neighbour to disconnect from
1040  */
1041 static void
1042 disconnect_neighbour (struct NeighbourMapEntry *n)
1043 {
1044   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1045               "Disconnecting from peer %s in state %s\n",
1046               GNUNET_i2s (&n->id),
1047               GNUNET_TRANSPORT_ps2s (n->state));
1048   /* depending on state, notify neighbour and/or upper layers of this peer
1049      about disconnect */
1050   switch (n->state)
1051   {
1052   case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
1053   case GNUNET_TRANSPORT_PS_INIT_ATS:
1054   case GNUNET_TRANSPORT_PS_INIT_BLACKLIST:
1055     /* other peer is completely unaware of us, no need to send DISCONNECT */
1056     set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED);
1057     free_neighbour (n, GNUNET_NO);
1058     return;
1059   case GNUNET_TRANSPORT_PS_CONNECT_SENT:
1060     send_disconnect (n);
1061     set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT);
1062     break;
1063   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND:
1064   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS:
1065   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST:
1066     /* we never ACK'ed the other peer's request, no need to send DISCONNECT */
1067     set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED);
1068     free_neighbour (n, GNUNET_NO);
1069     return;
1070   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK:
1071     /* we DID ACK the other peer's request, must send DISCONNECT */
1072     send_disconnect (n);
1073     set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT);
1074     break;
1075   case GNUNET_TRANSPORT_PS_CONNECTED:
1076   case GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST:
1077   case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
1078   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST:
1079   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT:
1080     /* we are currently connected, need to send disconnect and do
1081        internal notifications and update statistics */
1082     send_disconnect (n);
1083     GNUNET_STATISTICS_set (GST_stats,
1084                            gettext_noop ("# peers connected"),
1085                            --neighbours_connected,
1086                            GNUNET_NO);
1087     disconnect_notify_cb (callback_cls, &n->id);
1088     set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT);
1089     break;
1090   case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
1091     /* ATS address request timeout, disconnect without sending disconnect message */
1092     GNUNET_STATISTICS_set (GST_stats,
1093                            gettext_noop ("# peers connected"),
1094                            --neighbours_connected,
1095                            GNUNET_NO);
1096     disconnect_notify_cb (callback_cls, &n->id);
1097     set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT);
1098     break;
1099   case GNUNET_TRANSPORT_PS_DISCONNECT:
1100     /* already disconnected, ignore */
1101     break;
1102   case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
1103     /* already cleaned up, how did we get here!? */
1104     GNUNET_assert (0);
1105     break;
1106   default:
1107     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1108                 "Unhandled state `%s'\n",
1109                 GNUNET_TRANSPORT_ps2s (n->state));
1110     GNUNET_break (0);
1111     break;
1112   }
1113   /* schedule timeout to clean up */
1114   if (GNUNET_SCHEDULER_NO_TASK != n->task)
1115     GNUNET_SCHEDULER_cancel (n->task);
1116   n->task = GNUNET_SCHEDULER_add_delayed (DISCONNECT_SENT_TIMEOUT,
1117                                           &master_task, n);
1118 }
1119
1120
1121 /**
1122  * We're done with our transmission attempt, continue processing.
1123  *
1124  * @param cls the `struct MessageQueue` of the message
1125  * @param receiver intended receiver
1126  * @param success whether it worked or not
1127  * @param size_payload bytes payload sent
1128  * @param physical bytes sent on wire
1129  */
1130 static void
1131 transmit_send_continuation (void *cls,
1132                             const struct GNUNET_PeerIdentity *receiver,
1133                             int success, size_t size_payload, size_t physical)
1134 {
1135   struct MessageQueue *mq = cls;
1136   struct NeighbourMapEntry *n;
1137
1138   if (NULL == (n = lookup_neighbour (receiver)))
1139   {
1140     GNUNET_free (mq);
1141     return; /* disconnect or other error while transmitting, can happen */
1142   }
1143   if (n->is_active == mq)
1144   {
1145     /* this is still "our" neighbour, remove us from its queue
1146        and allow it to send the next message now */
1147     n->is_active = NULL;
1148     if (GNUNET_SCHEDULER_NO_TASK != n->task)
1149       GNUNET_SCHEDULER_cancel (n->task);
1150     n->task = GNUNET_SCHEDULER_add_now (&master_task, n);
1151   }
1152   if (bytes_in_send_queue < mq->message_buf_size)
1153   {
1154     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1155                 "Bytes_in_send_queue `%u', Message_size %u, result: %s, payload %u, on wire %u\n",
1156                 bytes_in_send_queue, mq->message_buf_size,
1157                 (GNUNET_OK == success) ? "OK" : "FAIL",
1158                 size_payload, physical);
1159     GNUNET_break (0);
1160   }
1161
1162
1163   GNUNET_break (size_payload == mq->message_buf_size);
1164   bytes_in_send_queue -= mq->message_buf_size;
1165   GNUNET_STATISTICS_set (GST_stats,
1166                         gettext_noop
1167                          ("# bytes in message queue for other peers"),
1168                          bytes_in_send_queue, GNUNET_NO);
1169   if (GNUNET_OK == success)
1170     GNUNET_STATISTICS_update (GST_stats,
1171                               gettext_noop
1172                               ("# messages transmitted to other peers"),
1173                               1, GNUNET_NO);
1174   else
1175     GNUNET_STATISTICS_update (GST_stats,
1176                               gettext_noop
1177                               ("# transmission failures for messages to other peers"),
1178                               1, GNUNET_NO);
1179   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1180               "Sending message to `%s' of type %u was a %s\n",
1181               GNUNET_i2s (receiver),
1182               ntohs (((struct GNUNET_MessageHeader *) mq->message_buf)->type),
1183               (success == GNUNET_OK) ? "success" : "FAILURE");
1184   if (NULL != mq->cont)
1185     mq->cont (mq->cont_cls, success, size_payload, physical);
1186   GNUNET_free (mq);
1187 }
1188
1189
1190 /**
1191  * Check the message list for the given neighbour and if we can
1192  * send a message, do so.  This function should only be called
1193  * if the connection is at least generally ready for transmission.
1194  * While we will only send one message at a time, no bandwidth
1195  * quota management is performed here.  If a message was given to
1196  * the plugin, the continuation will automatically re-schedule
1197  * the 'master' task once the next message might be transmitted.
1198  *
1199  * @param n target peer for which to transmit
1200  */
1201 static void
1202 try_transmission_to_peer (struct NeighbourMapEntry *n)
1203 {
1204   struct MessageQueue *mq;
1205   struct GNUNET_TIME_Relative timeout;
1206
1207   if (NULL == n->primary_address.address)
1208   {
1209     /* no address, why are we here? */
1210     GNUNET_break (0);
1211     return;
1212   }
1213   if ((0 == n->primary_address.address->address_length) &&
1214       (NULL == n->primary_address.session))
1215   {
1216     /* no address, why are we here? */
1217     GNUNET_break (0);
1218     return;
1219   }
1220   if (NULL != n->is_active)
1221   {
1222     /* transmission already pending */
1223     return;
1224   }
1225
1226   /* timeout messages from the queue that are past their due date */
1227   while (NULL != (mq = n->messages_head))
1228   {
1229     timeout = GNUNET_TIME_absolute_get_remaining (mq->timeout);
1230     if (timeout.rel_value_us > 0)
1231       break;
1232     GNUNET_STATISTICS_update (GST_stats,
1233                               gettext_noop
1234                               ("# messages timed out while in transport queue"),
1235                               1, GNUNET_NO);
1236     GNUNET_CONTAINER_DLL_remove (n->messages_head, n->messages_tail, mq);
1237     n->is_active = mq;
1238     transmit_send_continuation (mq, &n->id,
1239                                 GNUNET_SYSERR,
1240                                 mq->message_buf_size, 0);     /* timeout */
1241   }
1242   if (NULL == mq)
1243     return;                     /* no more messages */
1244   GNUNET_CONTAINER_DLL_remove (n->messages_head, n->messages_tail, mq);
1245   n->is_active = mq;
1246   (void) send_with_session (n,
1247                             mq->message_buf, mq->message_buf_size,
1248                             0 /* priority */, timeout, GNUNET_NO,
1249                             &transmit_send_continuation, mq);
1250 }
1251
1252
1253 /**
1254  * Send keepalive message to the neighbour.  Must only be called
1255  * if we are on 'connected' state or while trying to switch addresses.
1256  * Will internally determine if a keepalive is truly needed (so can
1257  * always be called).
1258  *
1259  * @param n neighbour that went idle and needs a keepalive
1260  */
1261 static void
1262 send_keepalive (struct NeighbourMapEntry *n)
1263 {
1264   struct SessionKeepAliveMessage m;
1265   struct GNUNET_TIME_Relative timeout;
1266   uint32_t nonce;
1267
1268   GNUNET_assert ((GNUNET_TRANSPORT_PS_CONNECTED == n->state) ||
1269                  (GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST == n->state) ||
1270                  (GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT));
1271   if (GNUNET_TIME_absolute_get_remaining (n->keep_alive_time).rel_value_us > 0)
1272     return; /* no keepalive needed at this time */
1273
1274   nonce = 0; /* 0 indicates 'not set' */
1275   while (0 == nonce)
1276     nonce = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
1277
1278   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1279       "Sending keep alive to peer `%s' with nonce %u\n",
1280       GNUNET_i2s (&n->id), nonce);
1281
1282   m.header.size = htons (sizeof (struct SessionKeepAliveMessage));
1283   m.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE);
1284   m.nonce = htonl (nonce);
1285
1286   timeout = send_with_session (n,
1287                                (const void *) &m, sizeof (m),
1288                                UINT32_MAX /* priority */,
1289                                GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES,
1290                                NULL, NULL);
1291   GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# keepalives sent"), 1,
1292                             GNUNET_NO);
1293   n->primary_address.keep_alive_nonce = nonce;
1294   n->expect_latency_response = GNUNET_YES;
1295   n->last_keep_alive_time = GNUNET_TIME_absolute_get ();
1296   n->keep_alive_time = GNUNET_TIME_relative_to_absolute (timeout);
1297
1298 }
1299
1300
1301 /**
1302  * Keep the connection to the given neighbour alive longer,
1303  * we received a KEEPALIVE (or equivalent); send a response.
1304  *
1305  * @param neighbour neighbour to keep alive (by sending keep alive response)
1306  * @param m the keep alive message containing the nonce to respond to
1307  */
1308 void
1309 GST_neighbours_keepalive (const struct GNUNET_PeerIdentity *neighbour,
1310     const struct GNUNET_MessageHeader *m)
1311 {
1312   struct NeighbourMapEntry *n;
1313   const struct SessionKeepAliveMessage *msg_in;
1314   struct SessionKeepAliveMessage msg;
1315
1316   if (sizeof (struct SessionKeepAliveMessage) != ntohs (m->size))
1317     return;
1318
1319   msg_in = (struct SessionKeepAliveMessage *) m;
1320   if (NULL == (n = lookup_neighbour (neighbour)))
1321   {
1322     GNUNET_STATISTICS_update (GST_stats,
1323                               gettext_noop
1324                               ("# KEEPALIVE messages discarded (peer unknown)"),
1325                               1, GNUNET_NO);
1326     return;
1327   }
1328   if (NULL == n->primary_address.session)
1329   {
1330     GNUNET_STATISTICS_update (GST_stats,
1331                               gettext_noop
1332                               ("# KEEPALIVE messages discarded (no session)"),
1333                               1, GNUNET_NO);
1334     return;
1335   }
1336
1337   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1338       "Received keep alive request from peer `%s' with nonce %u\n",
1339       GNUNET_i2s (&n->id), ntohl (msg_in->nonce));
1340
1341   /* send reply to allow neighbour to measure latency */
1342   msg.header.size = htons (sizeof (struct SessionKeepAliveMessage));
1343   msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE_RESPONSE);
1344   msg.nonce = msg_in->nonce;
1345   (void) send_with_session(n,
1346                            (const void *) &msg, sizeof (struct SessionKeepAliveMessage),
1347                            UINT32_MAX /* priority */,
1348                            GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES,
1349                            NULL, NULL);
1350 }
1351
1352
1353 /**
1354  * We received a KEEP_ALIVE_RESPONSE message and use this to calculate
1355  * latency to this peer.  Pass the updated information (existing ats
1356  * plus calculated latency) to ATS.
1357  *
1358  * @param neighbour neighbour to keep alive
1359  * @param m the message containing the keep alive response
1360  */
1361 void
1362 GST_neighbours_keepalive_response (const struct GNUNET_PeerIdentity *neighbour,
1363     const struct GNUNET_MessageHeader *m)
1364 {
1365   struct NeighbourMapEntry *n;
1366   const struct SessionKeepAliveMessage *msg;
1367   struct GNUNET_TRANSPORT_PluginFunctions *papi;
1368   uint32_t latency;
1369   struct GNUNET_ATS_Information ats;
1370
1371   if (sizeof (struct SessionKeepAliveMessage) != ntohs (m->size))
1372     return;
1373
1374   msg = (const struct SessionKeepAliveMessage *) m;
1375   if (NULL == (n = lookup_neighbour (neighbour)))
1376   {
1377     GNUNET_STATISTICS_update (GST_stats,
1378                               gettext_noop
1379                               ("# KEEPALIVE_RESPONSE messages discarded (not connected)"),
1380                               1, GNUNET_NO);
1381     return;
1382   }
1383   if ( (GNUNET_TRANSPORT_PS_CONNECTED != n->state) ||
1384        (GNUNET_YES != n->expect_latency_response) )
1385   {
1386     GNUNET_STATISTICS_update (GST_stats,
1387                               gettext_noop
1388                               ("# KEEPALIVE_RESPONSE messages discarded (not expected)"),
1389                               1, GNUNET_NO);
1390     return;
1391   }
1392   if (NULL == n->primary_address.address)
1393   {
1394     GNUNET_STATISTICS_update (GST_stats,
1395                               gettext_noop
1396                               ("# KEEPALIVE_RESPONSE messages discarded (address changed)"),
1397                               1, GNUNET_NO);
1398     return;
1399   }
1400   if (n->primary_address.keep_alive_nonce != ntohl (msg->nonce))
1401   {
1402     GNUNET_STATISTICS_update (GST_stats,
1403                               gettext_noop
1404                               ("# KEEPALIVE_RESPONSE messages discarded (wrong nonce)"),
1405                               1, GNUNET_NO);
1406     return;
1407   }
1408   else
1409   {
1410     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1411         "Received keep alive response from peer `%s' for session %p\n",
1412         GNUNET_i2s (&n->id), n->primary_address.session);
1413
1414   }
1415
1416   /* Update session timeout here */
1417   if (NULL != (papi = GST_plugins_find (n->primary_address.address->transport_name)))
1418   {
1419     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1420         "Updating session for peer `%s' for session %p\n",
1421         GNUNET_i2s (&n->id), n->primary_address.session);
1422     papi->update_session_timeout (papi->cls, &n->id, n->primary_address.session);
1423   }
1424   else
1425   {
1426     GNUNET_break (0);
1427   }
1428
1429   n->primary_address.keep_alive_nonce = 0;
1430   n->expect_latency_response = GNUNET_NO;
1431   n->latency = GNUNET_TIME_absolute_get_duration (n->last_keep_alive_time);
1432   set_timeout (n, GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT));
1433
1434   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1435               "Latency for peer `%s' is %s\n",
1436               GNUNET_i2s (&n->id),
1437               GNUNET_STRINGS_relative_time_to_string (n->latency,
1438                                                       GNUNET_YES));
1439   /* append latency */
1440   ats.type = htonl (GNUNET_ATS_QUALITY_NET_DELAY);
1441   if (n->latency.rel_value_us > UINT32_MAX)
1442     latency = UINT32_MAX;
1443   else
1444     latency = n->latency.rel_value_us;
1445   ats.value = htonl (latency);
1446   GST_ats_update_metrics (&n->id, n->primary_address.address,
1447       n->primary_address.session, &ats, 1);
1448 }
1449
1450
1451 /**
1452  * We have received a message from the given sender.  How long should
1453  * we delay before receiving more?  (Also used to keep the peer marked
1454  * as live).
1455  *
1456  * @param sender sender of the message
1457  * @param size size of the message
1458  * @param do_forward set to #GNUNET_YES if the message should be forwarded to clients
1459  *                   #GNUNET_NO if the neighbour is not connected or violates the quota,
1460  *                   #GNUNET_SYSERR if the connection is not fully up yet
1461  * @return how long to wait before reading more from this sender
1462  */
1463 struct GNUNET_TIME_Relative
1464 GST_neighbours_calculate_receive_delay (const struct GNUNET_PeerIdentity
1465                                         *sender, ssize_t size, int *do_forward)
1466 {
1467   struct NeighbourMapEntry *n;
1468   struct GNUNET_TIME_Relative ret;
1469
1470   if (NULL == neighbours)
1471   {
1472     *do_forward = GNUNET_NO;
1473     return GNUNET_TIME_UNIT_FOREVER_REL; /* This can happen during shutdown */
1474   }
1475   if (NULL == (n = lookup_neighbour (sender)))
1476   {
1477     GST_neighbours_try_connect (sender);
1478     if (NULL == (n = lookup_neighbour (sender)))
1479     {
1480       GNUNET_STATISTICS_update (GST_stats,
1481                                 gettext_noop
1482                                 ("# messages discarded due to lack of neighbour record"),
1483                                 1, GNUNET_NO);
1484       *do_forward = GNUNET_NO;
1485       return GNUNET_TIME_UNIT_ZERO;
1486     }
1487   }
1488   if (! test_connected (n))
1489   {
1490     *do_forward = GNUNET_SYSERR;
1491     return GNUNET_TIME_UNIT_ZERO;
1492   }
1493   if (GNUNET_YES == GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, size))
1494   {
1495     n->quota_violation_count++;
1496     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1497                 "Bandwidth quota (%u b/s) violation detected (total of %u).\n",
1498                 n->in_tracker.available_bytes_per_s__,
1499                 n->quota_violation_count);
1500     /* Discount 32k per violation */
1501     GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, -32 * 1024);
1502   }
1503   else
1504   {
1505     if (n->quota_violation_count > 0)
1506     {
1507       /* try to add 32k back */
1508       GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, 32 * 1024);
1509       n->quota_violation_count--;
1510     }
1511   }
1512   if (n->quota_violation_count > QUOTA_VIOLATION_DROP_THRESHOLD)
1513   {
1514     GNUNET_STATISTICS_update (GST_stats,
1515                               gettext_noop
1516                               ("# bandwidth quota violations by other peers"),
1517                               1, GNUNET_NO);
1518     *do_forward = GNUNET_NO;
1519     return GNUNET_CONSTANTS_QUOTA_VIOLATION_TIMEOUT;
1520   }
1521   *do_forward = GNUNET_YES;
1522   ret = GNUNET_BANDWIDTH_tracker_get_delay (&n->in_tracker, 32 * 1024);
1523   if (ret.rel_value_us > 0)
1524   {
1525     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1526                 "Throttling read (%llu bytes excess at %u b/s), waiting %s before reading more.\n",
1527                 (unsigned long long) n->in_tracker.
1528                 consumption_since_last_update__,
1529                 (unsigned int) n->in_tracker.available_bytes_per_s__,
1530                 GNUNET_STRINGS_relative_time_to_string (ret, GNUNET_YES));
1531     GNUNET_STATISTICS_update (GST_stats,
1532                               gettext_noop ("# ms throttling suggested"),
1533                               (int64_t) ret.rel_value_us / 1000LL,
1534                               GNUNET_NO);
1535   }
1536   return ret;
1537 }
1538
1539
1540 /**
1541  * Transmit a message to the given target using the active connection.
1542  *
1543  * @param target destination
1544  * @param msg message to send
1545  * @param msg_size number of bytes in msg
1546  * @param timeout when to fail with timeout
1547  * @param cont function to call when done
1548  * @param cont_cls closure for 'cont'
1549  */
1550 void
1551 GST_neighbours_send (const struct GNUNET_PeerIdentity *target, const void *msg,
1552                      size_t msg_size, struct GNUNET_TIME_Relative timeout,
1553                      GST_NeighbourSendContinuation cont, void *cont_cls)
1554 {
1555   struct NeighbourMapEntry *n;
1556   struct MessageQueue *mq;
1557
1558   /* All ove these cases should never happen; they are all API violations.
1559      But we check anyway, just to be sure. */
1560   if (NULL == (n = lookup_neighbour (target)))
1561   {
1562     GNUNET_break (0);
1563     if (NULL != cont)
1564       cont (cont_cls, GNUNET_SYSERR, msg_size, 0);
1565     return;
1566   }
1567   if (GNUNET_YES != test_connected (n))
1568   {
1569     GNUNET_break (0);
1570     if (NULL != cont)
1571       cont (cont_cls, GNUNET_SYSERR, msg_size, 0);
1572     return;
1573   }
1574   bytes_in_send_queue += msg_size;
1575   GNUNET_STATISTICS_set (GST_stats,
1576                          gettext_noop
1577                          ("# bytes in message queue for other peers"),
1578                          bytes_in_send_queue, GNUNET_NO);
1579   mq = GNUNET_malloc (sizeof (struct MessageQueue) + msg_size);
1580   mq->cont = cont;
1581   mq->cont_cls = cont_cls;
1582   memcpy (&mq[1], msg, msg_size);
1583   mq->message_buf = (const char *) &mq[1];
1584   mq->message_buf_size = msg_size;
1585   mq->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1586   GNUNET_CONTAINER_DLL_insert_tail (n->messages_head, n->messages_tail, mq);
1587   if ( (NULL != n->is_active) ||
1588        ( (NULL == n->primary_address.session) && (NULL == n->primary_address.address)) )
1589     return;
1590   if (GNUNET_SCHEDULER_NO_TASK != n->task)
1591     GNUNET_SCHEDULER_cancel (n->task);
1592   n->task = GNUNET_SCHEDULER_add_now (&master_task, n);
1593 }
1594
1595
1596 /**
1597  * Send a SESSION_CONNECT message via the given address.
1598  *
1599  * @param na address to use
1600  */
1601 static void
1602 send_session_connect (struct NeighbourAddress *na)
1603 {
1604   struct GNUNET_TRANSPORT_PluginFunctions *papi;
1605   struct SessionConnectMessage connect_msg;
1606
1607   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1608               "Sending SESSION_CONNECT message to peer %s\n",
1609               GNUNET_i2s (&na->address->peer));
1610   if (NULL == (papi = GST_plugins_find (na->address->transport_name)))
1611   {
1612     GNUNET_break (0);
1613     return;
1614   }
1615   if (NULL == na->session)
1616     na->session = papi->get_session (papi->cls, na->address);
1617   if (NULL == na->session)
1618   {
1619     GNUNET_break (0);
1620     return;
1621   }
1622   GNUNET_STATISTICS_update (GST_stats,
1623                             gettext_noop
1624                             ("# SESSION_CONNECT messages sent"),
1625                             1, GNUNET_NO);
1626   na->connect_timestamp = GNUNET_TIME_absolute_get ();
1627   connect_msg.header.size = htons (sizeof (struct SessionConnectMessage));
1628   connect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_CONNECT);
1629   connect_msg.reserved = htonl (0);
1630   connect_msg.timestamp = GNUNET_TIME_absolute_hton (na->connect_timestamp);
1631   if (-1 ==
1632       papi->send (papi->cls,
1633                   na->session,
1634                   (const char *) &connect_msg, sizeof (struct SessionConnectMessage),
1635                   UINT_MAX,
1636                   GNUNET_TIME_UNIT_FOREVER_REL,
1637                   NULL, NULL))
1638   {
1639     GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1640                 _("Failed to transmit CONNECT message via plugin to %s\n"),
1641                 GST_plugins_a2s (na->address));
1642   }
1643   GST_neighbours_notify_data_sent (&na->address->peer,
1644                                    na->address,
1645                                    na->session,
1646                                    sizeof (struct SessionConnectMessage));
1647
1648 }
1649
1650
1651 /**
1652  * Send a SESSION_CONNECT_ACK message via the given address.
1653  *
1654  * @param address address to use
1655  * @param session session to use
1656  * @param timestamp timestamp to use for the ACK message
1657  */
1658 static void
1659 send_session_connect_ack_message (const struct GNUNET_HELLO_Address *address,
1660                                   struct Session *session,
1661                                   struct GNUNET_TIME_Absolute timestamp)
1662 {
1663   struct GNUNET_TRANSPORT_PluginFunctions *papi;
1664   struct SessionConnectMessage connect_msg;
1665
1666   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1667               "Sending CONNECT_ACK to peer `%s'\n",
1668               GNUNET_i2s (&address->peer));
1669   if (NULL == (papi = GST_plugins_find (address->transport_name)))
1670   {
1671     GNUNET_break (0);
1672     return;
1673   }
1674   if (NULL == session)
1675     session = papi->get_session (papi->cls, address);
1676   if (NULL == session)
1677   {
1678     GNUNET_break (0);
1679     return;
1680   }
1681   GNUNET_STATISTICS_update (GST_stats,
1682                             gettext_noop
1683                             ("# CONNECT_ACK messages sent"),
1684                             1, GNUNET_NO);
1685   connect_msg.header.size = htons (sizeof (struct SessionConnectMessage));
1686   connect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_CONNECT_ACK);
1687   connect_msg.reserved = htonl (0);
1688   connect_msg.timestamp = GNUNET_TIME_absolute_hton (timestamp);
1689   (void) papi->send (papi->cls,
1690                      session,
1691                      (const char *) &connect_msg, sizeof (struct SessionConnectMessage),
1692                      UINT_MAX,
1693                      GNUNET_TIME_UNIT_FOREVER_REL,
1694                      NULL, NULL);
1695
1696 }
1697
1698 struct QuotaNotificationRequest
1699 {
1700   struct GNUNET_PeerIdentity peer;
1701   struct Session *session;
1702   char *plugin;
1703 };
1704
1705 struct QNR_LookContext
1706 {
1707   struct GNUNET_PeerIdentity peer;
1708   struct Session *session;
1709   const char *plugin;
1710
1711   struct QuotaNotificationRequest *res;
1712 };
1713
1714 static int
1715 find_notification_request (void *cls, const struct GNUNET_PeerIdentity *key, void *value)
1716 {
1717   struct QNR_LookContext *qnr_ctx = cls;
1718   struct QuotaNotificationRequest *qnr = value;
1719
1720   if ((qnr->session == qnr_ctx->session) &&
1721       (0 == memcmp (&qnr->peer, &qnr_ctx->peer, sizeof (struct GNUNET_PeerIdentity))) &&
1722       (0 == strcmp(qnr_ctx->plugin, qnr->plugin)))
1723   {
1724     qnr_ctx->res = value;
1725     return GNUNET_NO;
1726   }
1727   return GNUNET_YES;
1728 }
1729
1730 void
1731 GST_neighbours_register_quota_notification(void *cls,
1732     const struct GNUNET_PeerIdentity *peer, const char *plugin,
1733     struct Session *session)
1734 {
1735   struct QuotaNotificationRequest *qnr;
1736   struct QNR_LookContext qnr_ctx;
1737
1738   if (NULL == registered_quota_notifications)
1739   {
1740     return; /* init or shutdown */
1741   }
1742
1743   qnr_ctx.peer = (*peer);
1744   qnr_ctx.plugin = plugin;
1745   qnr_ctx.session = session;
1746   qnr_ctx.res = NULL;
1747
1748   GNUNET_CONTAINER_multipeermap_get_multiple (registered_quota_notifications,
1749       peer, &find_notification_request, &qnr_ctx);
1750   if (NULL != qnr_ctx.res)
1751   {
1752     GNUNET_break(0);
1753     return;
1754   }
1755
1756   qnr = GNUNET_new (struct QuotaNotificationRequest);
1757   qnr->peer =  (*peer);
1758   qnr->plugin = GNUNET_strdup (plugin);
1759   qnr->session = session;
1760
1761   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1762       "Adding notification for peer `%s' plugin `%s' session %p \n",
1763       GNUNET_i2s (peer), plugin, session);
1764
1765   GNUNET_CONTAINER_multipeermap_put (registered_quota_notifications, peer,
1766       qnr, GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
1767 }
1768
1769
1770 void
1771 GST_neighbours_unregister_quota_notification(void *cls,
1772     const struct GNUNET_PeerIdentity *peer, const char *plugin, struct Session *session)
1773 {
1774   struct QNR_LookContext qnr_ctx;
1775
1776   if (NULL == registered_quota_notifications)
1777   {
1778     return; /* init or shutdown */
1779   }
1780
1781   qnr_ctx.peer = (*peer);
1782   qnr_ctx.plugin = plugin;
1783   qnr_ctx.session = session;
1784   qnr_ctx.res = NULL;
1785
1786   GNUNET_CONTAINER_multipeermap_iterate (registered_quota_notifications,
1787       &find_notification_request, &qnr_ctx);
1788   if (NULL == qnr_ctx.res)
1789   {
1790     GNUNET_break(0);
1791     return;
1792   }
1793
1794   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1795       "Removing notification for peer `%s' plugin `%s' session %p \n",
1796       GNUNET_i2s (peer), plugin, session);
1797
1798   GNUNET_CONTAINER_multipeermap_remove (registered_quota_notifications, peer,
1799       qnr_ctx.res);
1800   GNUNET_free (qnr_ctx.res->plugin);
1801   GNUNET_free (qnr_ctx.res);
1802 }
1803
1804 static int
1805 notification_cb(void *cls, const struct GNUNET_PeerIdentity *key, void *value)
1806 {
1807   /* struct NeighbourMapEntry *n = cls; */
1808   struct QuotaNotificationRequest *qnr = value;
1809   struct GNUNET_TRANSPORT_PluginFunctions *papi;
1810   struct GNUNET_TIME_Relative delay;
1811   int do_forward;
1812
1813   papi = GST_plugins_find(qnr->plugin);
1814   if (NULL == papi)
1815   {
1816     GNUNET_break (0);
1817     return GNUNET_OK;
1818   }
1819
1820   delay = GST_neighbours_calculate_receive_delay (key, 0, &do_forward);
1821   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1822       "New inbound delay for peer `%s' is %llu ms\n", GNUNET_i2s (key),
1823       delay.rel_value_us / 1000);
1824
1825   if (NULL != papi->update_inbound_delay)
1826     papi->update_inbound_delay (papi->cls, key, qnr->session, delay);
1827   return GNUNET_OK;
1828 }
1829
1830 static
1831 int
1832 free_notification_cb(void *cls, const struct GNUNET_PeerIdentity *key,
1833     void *value)
1834 {
1835   /* struct NeighbourMapEntry *n = cls; */
1836   struct QuotaNotificationRequest *qnr = value;
1837
1838   GNUNET_CONTAINER_multipeermap_remove (registered_quota_notifications, key,
1839       qnr);
1840   GNUNET_free(qnr->plugin);
1841   GNUNET_free(qnr);
1842
1843   return GNUNET_OK;
1844 }
1845
1846 static void
1847 inbound_bw_tracker_update(void *cls)
1848 {
1849   struct NeighbourMapEntry *n = cls;
1850
1851   /* Quota was updated, tell plugins to update the time to receive next */
1852   GNUNET_CONTAINER_multipeermap_get_multiple (registered_quota_notifications,
1853       &n->id, &notification_cb, n);
1854 }
1855
1856
1857 /**
1858  * Create a fresh entry in the neighbour map for the given peer
1859  *
1860  * @param peer peer to create an entry for
1861  * @return new neighbour map entry
1862  */
1863 static struct NeighbourMapEntry *
1864 setup_neighbour (const struct GNUNET_PeerIdentity *peer)
1865 {
1866   struct NeighbourMapEntry *n;
1867
1868   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1869               "Creating new neighbour entry for `%s'\n",
1870               GNUNET_i2s (peer));
1871   n = GNUNET_new (struct NeighbourMapEntry);
1872   n->id = *peer;
1873   n->latency = GNUNET_TIME_UNIT_FOREVER_REL;
1874   n->last_util_transmission = GNUNET_TIME_absolute_get();
1875   n->util_payload_bytes_recv = 0;
1876   n->util_payload_bytes_sent = 0;
1877   n->util_total_bytes_recv = 0;
1878   n->util_total_bytes_sent = 0;
1879   GNUNET_BANDWIDTH_tracker_init (&n->in_tracker, &inbound_bw_tracker_update, n,
1880                                  GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
1881                                  MAX_BANDWIDTH_CARRY_S);
1882   n->task = GNUNET_SCHEDULER_add_now (&master_task, n);
1883   set_state_and_timeout (n, GNUNET_TRANSPORT_PS_NOT_CONNECTED, GNUNET_TIME_UNIT_FOREVER_ABS);
1884   GNUNET_assert (GNUNET_OK ==
1885                  GNUNET_CONTAINER_multipeermap_put (neighbours,
1886                                                     &n->id, n,
1887                                                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
1888   return n;
1889 }
1890
1891
1892 /**
1893  * Check if the two given addresses are the same.
1894  * Actually only checks if the sessions are non-NULL
1895  * (which they should be) and then if they are identical;
1896  * the actual addresses don't matter if the session
1897  * pointers match anyway, and we must have session pointers
1898  * at this time.
1899  *
1900  * @param a1 first address to compare
1901  * @param a2 other address to compare
1902  * @return #GNUNET_NO if the addresses do not match, #GNUNET_YES if they do match
1903  */
1904 static int
1905 address_matches (const struct NeighbourAddress *a1,
1906                  const struct NeighbourAddress *a2)
1907 {
1908   if ( (NULL == a1->session) ||
1909        (NULL == a2->session) )
1910   {
1911     GNUNET_break (0);
1912     return 0;
1913   }
1914   return (a1->session == a2->session) ? GNUNET_YES : GNUNET_NO;
1915 }
1916
1917
1918 /* We received a address suggestion after requesting an address in
1919  * try_connect or after receiving a connect, switch to address
1920  */
1921 static void
1922 address_suggest_cont (void *cls,
1923     const struct GNUNET_PeerIdentity *peer,
1924     const struct GNUNET_HELLO_Address *address, struct Session *session,
1925     struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out,
1926     struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
1927     const struct GNUNET_ATS_Information *ats, uint32_t ats_count)
1928 {
1929   GST_neighbours_switch_to_address(peer, address, session, ats, ats_count,
1930       bandwidth_in, bandwidth_out);
1931 }
1932
1933
1934 struct BlacklistCheckSwitchContext
1935 {
1936   struct BlacklistCheckSwitchContext *prev;
1937   struct BlacklistCheckSwitchContext *next;
1938
1939
1940   struct GST_BlacklistCheck *blc;
1941
1942   struct GNUNET_HELLO_Address *address;
1943   struct Session *session;
1944   struct GNUNET_ATS_Information *ats;
1945   uint32_t ats_count;
1946
1947   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in;
1948   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out;
1949 };
1950
1951 /**
1952  * Black list check result for try_connect call
1953  * If connection to the peer is allowed request adddress and
1954  *
1955  * @param cls blc_ctx bl context
1956  * @param peer the peer
1957  * @param result the result
1958  */
1959 static void
1960 try_connect_bl_check_cont (void *cls,
1961     const struct GNUNET_PeerIdentity *peer, int result)
1962 {
1963   struct BlacklistCheckSwitchContext *blc_ctx = cls;
1964   struct NeighbourMapEntry *n;
1965
1966   GNUNET_CONTAINER_DLL_remove (pending_bc_head, pending_bc_tail, blc_ctx);
1967   GNUNET_free (blc_ctx);
1968
1969   if (GNUNET_OK != result)
1970   {
1971     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1972         _("Blacklisting dissaproved to connect to peer `%s'\n"),
1973         GNUNET_i2s (peer));
1974     return;
1975   }
1976   n = setup_neighbour (peer);
1977   set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_ATS,
1978       GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
1979
1980   GNUNET_ATS_reset_backoff (GST_ats, peer);
1981   n->suggest_handle = GNUNET_ATS_suggest_address (GST_ats, peer,
1982       &address_suggest_cont, n);
1983 }
1984
1985
1986
1987 /**
1988  * Try to create a connection to the given target (eventually).
1989  *
1990  * @param target peer to try to connect to
1991  */
1992 void
1993 GST_neighbours_try_connect (const struct GNUNET_PeerIdentity *target)
1994 {
1995   struct NeighbourMapEntry *n;
1996   struct GST_BlacklistCheck *blc;
1997   struct BlacklistCheckSwitchContext *blc_ctx;
1998
1999   if (NULL == neighbours)
2000   {
2001     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2002                 "Asked to connect to peer `%s' during shutdown\n",
2003                 GNUNET_i2s (target));
2004     return; /* during shutdown, do nothing */
2005   }
2006   n = lookup_neighbour (target);
2007   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2008               "Asked to connect to peer `%s' (state: %s)\n",
2009               GNUNET_i2s (target),
2010               (NULL != n) ? GNUNET_TRANSPORT_ps2s(n->state) : "NEW PEER");
2011   if (NULL != n)
2012   {
2013     switch (n->state)
2014     {
2015     case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
2016       /* this should not be possible */
2017       GNUNET_break (0);
2018       free_neighbour (n, GNUNET_NO);
2019       break;
2020     case GNUNET_TRANSPORT_PS_INIT_ATS:
2021     case GNUNET_TRANSPORT_PS_INIT_BLACKLIST:
2022     case GNUNET_TRANSPORT_PS_CONNECT_SENT:
2023     case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND:
2024     case GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS:
2025     case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST:
2026     case GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK:
2027       GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2028                   "Ignoring request to try to connect to `%s', already trying!\n",
2029                   GNUNET_i2s (target));
2030       return; /* already trying */
2031     case GNUNET_TRANSPORT_PS_CONNECTED:
2032     case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
2033     case GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST:
2034     case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
2035     case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST:
2036     case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT:
2037       GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2038                   "Ignoring request to try to connect, already connected to `%s'!\n",
2039                   GNUNET_i2s (target));
2040       return; /* already connected */
2041     case GNUNET_TRANSPORT_PS_DISCONNECT:
2042       /* get rid of remains, ready to re-try immediately */
2043       free_neighbour (n, GNUNET_NO);
2044       break;
2045     case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
2046       /* should not be possible */
2047       GNUNET_assert (0);
2048     default:
2049       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2050                   "Unhandled state `%s'\n",
2051                   GNUNET_TRANSPORT_ps2s (n->state));
2052       GNUNET_break (0);
2053       free_neighbour (n, GNUNET_NO);
2054       break;
2055     }
2056   }
2057
2058   /* Do blacklist check if connecting to this peer is allowed */
2059   blc_ctx = GNUNET_new (struct BlacklistCheckSwitchContext);
2060   GNUNET_CONTAINER_DLL_insert (pending_bc_head, pending_bc_tail, blc_ctx);
2061
2062   if (NULL != (blc = GST_blacklist_test_allowed (target, NULL,
2063         &try_connect_bl_check_cont, blc_ctx)))
2064   {
2065     blc_ctx->blc = blc;
2066   }
2067 }
2068
2069
2070 /**
2071  * Function called with the result of a blacklist check.
2072  *
2073  * @param cls closure with the `struct BlackListCheckContext`
2074  * @param peer peer this check affects
2075  * @param result #GNUNET_OK if the address is allowed
2076  */
2077 static void
2078 handle_test_blacklist_cont (void *cls,
2079                             const struct GNUNET_PeerIdentity *peer,
2080                             int result)
2081 {
2082   struct BlackListCheckContext *bcc = cls;
2083   struct NeighbourMapEntry *n;
2084
2085   bcc->bc = NULL;
2086   GNUNET_CONTAINER_DLL_remove (bc_head,
2087                                bc_tail,
2088                                bcc);
2089   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2090               "Connection to new address of peer `%s' based on blacklist is `%s'\n",
2091               GNUNET_i2s (peer),
2092               (GNUNET_OK == result) ? "allowed" : "FORBIDDEN");
2093   if (GNUNET_OK == result)
2094   {
2095     GST_ats_add_address (bcc->na.address, bcc->na.session, NULL, 0);
2096   }
2097   else
2098   {
2099     /* Blacklist disagreed on connecting to a peer with this address
2100      * Destroy address because we are not allowed to use it
2101      */
2102     if (NULL != bcc->na.session)
2103       GNUNET_ATS_address_destroyed (GST_ats, bcc->na.address, bcc->na.session);
2104     GNUNET_ATS_address_destroyed (GST_ats, bcc->na.address, NULL);
2105   }
2106   if (NULL == (n = lookup_neighbour (peer)))
2107   {
2108     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2109                 "No neighbor entry for peer `%s', ignoring blacklist result\n",
2110                 GNUNET_i2s (peer));
2111     goto cleanup; /* nobody left to care about new address */
2112   }
2113   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2114               "Received blacklist result for peer `%s' in state %s/%d\n",
2115               GNUNET_i2s (peer),
2116               GNUNET_TRANSPORT_ps2s (n->state),
2117               n->send_connect_ack);
2118   switch (n->state)
2119   {
2120   case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
2121     /* this should not be possible */
2122     GNUNET_break (0);
2123     free_neighbour (n, GNUNET_NO);
2124     break;
2125   case GNUNET_TRANSPORT_PS_INIT_ATS:
2126     /* waiting on ATS suggestion; still, pass address to ATS as a
2127        possibility */
2128     break;
2129   case GNUNET_TRANSPORT_PS_INIT_BLACKLIST:
2130     /* check if the address the blacklist was fine with matches
2131        ATS suggestion, if so, we can move on! */
2132     if ( (GNUNET_OK == result) &&
2133          (1 == n->send_connect_ack) )
2134     {
2135       n->send_connect_ack = 2;
2136       send_session_connect_ack_message (bcc->na.address,
2137                                         bcc->na.session,
2138                                         n->connect_ack_timestamp);
2139     }
2140     if (GNUNET_YES != address_matches (&bcc->na, &n->primary_address))
2141     {
2142       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2143                   "Blacklist result for peer %s is for non-primary address, ignored\n",
2144                   GNUNET_i2s (peer));
2145       break; /* result for an address we currently don't care about */
2146     }
2147     if (GNUNET_OK == result)
2148     {
2149       set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECT_SENT,
2150           GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT));
2151       send_session_connect (&n->primary_address);
2152     }
2153     else
2154     {
2155       free_address (&n->primary_address);
2156       set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_ATS,
2157           GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
2158     }
2159     break;
2160   case GNUNET_TRANSPORT_PS_CONNECT_SENT:
2161     /* waiting on CONNECT_ACK, send ACK if one is pending */
2162     if ( (GNUNET_OK == result) &&
2163          (1 == n->send_connect_ack) )
2164     {
2165       n->send_connect_ack = 2;
2166       send_session_connect_ack_message (n->primary_address.address,
2167                                         n->primary_address.session,
2168                                         n->connect_ack_timestamp);
2169     }
2170     break;
2171   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND:
2172     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS,
2173         GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
2174     GNUNET_ATS_reset_backoff (GST_ats, peer);
2175     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2176                 "Suggesting address for peer %s to ATS\n",
2177                 GNUNET_i2s (peer));
2178     n->suggest_handle = GNUNET_ATS_suggest_address (GST_ats, peer,
2179         &address_suggest_cont, n);
2180     break;
2181   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS:
2182     /* waiting on ATS suggestion, don't care about blacklist */
2183     break;
2184   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST:
2185     if (GNUNET_YES != address_matches (&bcc->na, &n->primary_address))
2186     {
2187       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2188                   "Blacklist result ignored, as it is not for our primary address\n");
2189       break; /* result for an address we currently don't care about */
2190     }
2191     if (GNUNET_OK == result)
2192     {
2193       set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK,
2194           GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT));
2195       send_session_connect_ack_message (bcc->na.address,
2196                                         bcc->na.session,
2197                                         n->connect_ack_timestamp);
2198       if (1 == n->send_connect_ack)
2199         n->send_connect_ack = 2;
2200     }
2201     else
2202     {
2203       struct GNUNET_TRANSPORT_PluginFunctions *plugin;
2204
2205       plugin = GST_plugins_find (bcc->na.address->transport_name);
2206       if ( (NULL != plugin) &&
2207            (NULL != bcc->na.session) )
2208       {
2209         plugin->disconnect_session (plugin->cls,
2210                                     bcc->na.session);
2211         break;
2212       }
2213       GNUNET_break (NULL != plugin);
2214       free_address (&n->primary_address);
2215       set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_ATS,
2216           GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
2217       GNUNET_ATS_reset_backoff (GST_ats, peer);
2218     }
2219     break;
2220   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK:
2221     /* waiting on SESSION_ACK, send ACK if one is pending */
2222     if ( (GNUNET_OK == result) &&
2223          (1 == n->send_connect_ack) )
2224     {
2225       n->send_connect_ack = 2;
2226       send_session_connect_ack_message (n->primary_address.address,
2227                                         n->primary_address.session,
2228                                         n->connect_ack_timestamp);
2229     }
2230     break;
2231   case GNUNET_TRANSPORT_PS_CONNECTED:
2232     /* already connected, don't care about blacklist */
2233     break;
2234   case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
2235     /* still waiting on ATS suggestion, don't care about blacklist */
2236     break;
2237   case GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST:
2238     if ( (GNUNET_OK == result) &&
2239          (1 == n->send_connect_ack) )
2240     {
2241       n->send_connect_ack = 2;
2242       send_session_connect_ack_message (bcc->na.address,
2243                                         bcc->na.session,
2244                                         n->connect_ack_timestamp);
2245     }
2246     if (GNUNET_YES != address_matches (&bcc->na, &n->primary_address))
2247     {
2248       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2249                   "Blacklist result ignored, as it is not for our primary address\n");
2250       break; /* result for an address we currently don't care about */
2251     }
2252     if (GNUNET_OK == result)
2253     {
2254       set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_SENT, GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT));
2255       send_session_connect (&n->primary_address);
2256     }
2257     else
2258     {
2259       set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
2260     }
2261     break;
2262   case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
2263     /* waiting on CONNECT_ACK, don't care about blacklist */
2264     if ( (GNUNET_OK == result) &&
2265          (1 == n->send_connect_ack) )
2266     {
2267       n->send_connect_ack = 2;
2268       send_session_connect_ack_message (n->primary_address.address,
2269                                         n->primary_address.session,
2270                                         n->connect_ack_timestamp);
2271     }
2272     break;
2273   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST:
2274     if (GNUNET_YES != address_matches (&bcc->na, &n->alternative_address))
2275     {
2276       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2277                   "Blacklist result ignored, as it is not for our primary address\n");
2278       break; /* result for an address we currently don't care about */
2279     }
2280     if (GNUNET_OK == result)
2281     {
2282       send_session_connect (&n->alternative_address);
2283       set_state (n, GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT);
2284     }
2285     else
2286     {
2287       set_state(n, GNUNET_TRANSPORT_PS_CONNECTED);
2288       free_address (&n->alternative_address);
2289     }
2290     break;
2291   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT:
2292     /* waiting on CONNECT_ACK, don't care about blacklist */
2293     if ( (GNUNET_OK == result) &&
2294          (1 == n->send_connect_ack) )
2295     {
2296       n->send_connect_ack = 2;
2297       send_session_connect_ack_message (n->primary_address.address,
2298                                         n->primary_address.session,
2299                                         n->connect_ack_timestamp);
2300     }
2301     break;
2302   case GNUNET_TRANSPORT_PS_DISCONNECT:
2303     /* Nothing to do here, ATS will already do what can be done */
2304     break;
2305   case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
2306     /* should not be possible */
2307     GNUNET_assert (0);
2308     break;
2309   default:
2310     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2311                 "Unhandled state `%s'\n",
2312                 GNUNET_TRANSPORT_ps2s (n->state));
2313     GNUNET_break (0);
2314     free_neighbour (n, GNUNET_NO);
2315     break;
2316   }
2317  cleanup:
2318   GNUNET_HELLO_address_free (bcc->na.address);
2319   GNUNET_free (bcc);
2320 }
2321
2322
2323 /**
2324  * We want to know if connecting to a particular peer via
2325  * a particular address is allowed.  Check it!
2326  *
2327  * @param peer identity of the peer to switch the address for
2328  * @param ts time at which the check was initiated
2329  * @param address address of the other peer, NULL if other peer
2330  *                       connected to us
2331  * @param session session to use (or NULL)
2332  */
2333 static void
2334 check_blacklist (const struct GNUNET_PeerIdentity *peer,
2335                  struct GNUNET_TIME_Absolute ts,
2336                  const struct GNUNET_HELLO_Address *address,
2337                  struct Session *session)
2338 {
2339   struct BlackListCheckContext *bcc;
2340   struct GST_BlacklistCheck *bc;
2341
2342   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2343               "Checking peer `%s' against blacklist\n",
2344               GNUNET_i2s (peer));
2345   bcc = GNUNET_new (struct BlackListCheckContext);
2346   bcc->na.address = GNUNET_HELLO_address_copy (address);
2347   bcc->na.session = session;
2348   bcc->na.connect_timestamp = ts;
2349   GNUNET_CONTAINER_DLL_insert (bc_head,
2350                                bc_tail,
2351                                bcc);
2352   if (NULL != (bc = GST_blacklist_test_allowed (peer,
2353                                                 address->transport_name,
2354                                                 &handle_test_blacklist_cont, bcc)))
2355     bcc->bc = bc;
2356   /* if NULL == bc, 'cont' was already called and 'bcc' already free'd, so
2357      we must only store 'bc' if 'bc' is non-NULL... */
2358 }
2359
2360
2361 /**
2362  * We received a 'SESSION_CONNECT' message from the other peer.
2363  * Consider switching to it.
2364  *
2365  * @param message possibly a 'struct SessionConnectMessage' (check format)
2366  * @param peer identity of the peer to switch the address for
2367  * @param address address of the other peer, NULL if other peer
2368  *                       connected to us
2369  * @param session session to use (or NULL)
2370  * @return #GNUNET_OK if the message was fine, #GNUNET_SYSERR on serious error
2371  */
2372 int
2373 GST_neighbours_handle_connect (const struct GNUNET_MessageHeader *message,
2374                                const struct GNUNET_PeerIdentity *peer,
2375                                const struct GNUNET_HELLO_Address *address,
2376                                struct Session *session)
2377 {
2378   const struct SessionConnectMessage *scm;
2379   struct NeighbourMapEntry *n;
2380   struct GNUNET_TIME_Absolute ts;
2381
2382   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2383               "Received CONNECT message from peer `%s'\n",
2384               GNUNET_i2s (peer));
2385   if (ntohs (message->size) != sizeof (struct SessionConnectMessage))
2386   {
2387     GNUNET_break_op (0);
2388     return GNUNET_SYSERR;
2389   }
2390   GNUNET_STATISTICS_update (GST_stats,
2391                             gettext_noop
2392                             ("# CONNECT messages received"),
2393                             1, GNUNET_NO);
2394   if (NULL == neighbours)
2395   {
2396     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2397                 _("CONNECT request from peer `%s' ignored due impending shutdown\n"),
2398                 GNUNET_i2s (peer));
2399     return GNUNET_OK; /* we're shutting down */
2400   }
2401   scm = (const struct SessionConnectMessage *) message;
2402   GNUNET_break_op (0 == ntohl (scm->reserved));
2403   ts = GNUNET_TIME_absolute_ntoh (scm->timestamp);
2404   n = lookup_neighbour (peer);
2405   if (NULL == n)
2406     n = setup_neighbour (peer);
2407   n->send_connect_ack = 1;
2408   n->connect_ack_timestamp = ts;
2409
2410   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2411               "Received SESSION_CONNECT for peer `%s' in state %s/%d\n",
2412               GNUNET_i2s (peer),
2413               GNUNET_TRANSPORT_ps2s (n->state),
2414               n->send_connect_ack);
2415   switch (n->state)
2416   {
2417   case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
2418     /* Do a blacklist check for the new address */
2419     set_state (n, GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND);
2420     check_blacklist (peer, ts, address, session);
2421     break;
2422   case GNUNET_TRANSPORT_PS_INIT_ATS:
2423     /* CONNECT message takes priority over us asking ATS for address */
2424     set_state (n, GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND);
2425     /* fallthrough */
2426   case GNUNET_TRANSPORT_PS_INIT_BLACKLIST:
2427   case GNUNET_TRANSPORT_PS_CONNECT_SENT:
2428   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND:
2429   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS:
2430   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST:
2431   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK:
2432     /* It can never hurt to have an alternative address in the above cases,
2433        see if it is allowed */
2434     check_blacklist (peer, ts, address, session);
2435     break;
2436   case GNUNET_TRANSPORT_PS_CONNECTED:
2437     /* we are already connected and can thus send the ACK immediately;
2438        still, it can never hurt to have an alternative address, so also
2439        tell ATS  about it */
2440     GNUNET_assert (NULL != n->primary_address.address);
2441     GNUNET_assert (NULL != n->primary_address.session);
2442     n->send_connect_ack = 0;
2443     send_session_connect_ack_message (n->primary_address.address,
2444                                       n->primary_address.session, ts);
2445     check_blacklist (peer, ts, address, session);
2446     break;
2447   case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
2448   case GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST:
2449   case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
2450     /* It can never hurt to have an alternative address in the above cases,
2451        see if it is allowed */
2452     check_blacklist (peer, ts, address, session);
2453     break;
2454   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST:
2455   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT:
2456     /* we are already connected and can thus send the ACK immediately;
2457        still, it can never hurt to have an alternative address, so also
2458        tell ATS  about it */
2459     GNUNET_assert (NULL != n->primary_address.address);
2460     GNUNET_assert (NULL != n->primary_address.session);
2461     n->send_connect_ack = 0;
2462     send_session_connect_ack_message (n->primary_address.address,
2463                                       n->primary_address.session, ts);
2464     check_blacklist (peer, ts, address, session);
2465     break;
2466   case GNUNET_TRANSPORT_PS_DISCONNECT:
2467     /* get rid of remains without terminating sessions, ready to re-try */
2468     free_neighbour (n, GNUNET_YES);
2469     n = setup_neighbour (peer);
2470     set_state (n, GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS);
2471     GNUNET_ATS_reset_backoff (GST_ats, peer);
2472     break;
2473   case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
2474     /* should not be possible */
2475     GNUNET_assert (0);
2476     break;
2477   default:
2478     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2479                 "Unhandled state `%s'\n",
2480                 GNUNET_TRANSPORT_ps2s (n->state));
2481     GNUNET_break (0);
2482     return GNUNET_SYSERR;
2483   }
2484   return GNUNET_OK;
2485 }
2486
2487 static void
2488 switch_address_bl_check_cont (void *cls,
2489     const struct GNUNET_PeerIdentity *peer, int result)
2490 {
2491   struct BlacklistCheckSwitchContext *blc_ctx = cls;
2492   struct GNUNET_TRANSPORT_PluginFunctions *papi;
2493   struct NeighbourMapEntry *n;
2494
2495   if ( (NULL == (n = lookup_neighbour (peer))) || (result == GNUNET_NO) ||
2496        (NULL == (papi = GST_plugins_find (blc_ctx->address->transport_name))) )
2497   {
2498     if (NULL == n)
2499     {
2500       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2501                   "Peer %s is unknown, suggestion ignored\n",
2502                   GNUNET_i2s (peer));
2503     }
2504     if (result == GNUNET_NO)
2505     {
2506       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2507           "Blacklist denied to switch to suggested address `%s' sesion %p for peer `%s'\n",
2508           GST_plugins_a2s (blc_ctx->address),
2509           blc_ctx->session,
2510           GNUNET_i2s (&blc_ctx->address->peer));
2511     }
2512     /* Delete address (or session if existing) in ATS */
2513     GNUNET_ATS_address_destroyed (GST_ats, blc_ctx->address, blc_ctx->session);
2514
2515     GNUNET_CONTAINER_DLL_remove (pending_bc_head, pending_bc_tail, blc_ctx);
2516     GNUNET_HELLO_address_free(blc_ctx->address);
2517     GNUNET_free_non_null (blc_ctx->ats);
2518     GNUNET_free (blc_ctx);
2519     return;
2520   }
2521
2522   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2523       "Blacklist accepted to switch to suggested address `%s' for peer `%s'\n",
2524       GST_plugins_a2s (blc_ctx->address),
2525       blc_ctx->session,
2526       GNUNET_i2s (&blc_ctx->address->peer));
2527
2528   if (NULL == blc_ctx->session)
2529   {
2530     blc_ctx->session = papi->get_session (papi->cls, blc_ctx->address);
2531     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2532                 "Obtained new session for peer `%s' and  address '%s': %p\n",
2533                 GNUNET_i2s (&blc_ctx->address->peer), GST_plugins_a2s (blc_ctx->address), blc_ctx->session);
2534   }
2535   if (NULL == blc_ctx->session)
2536   {
2537     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2538                 "Failed to obtain new session for peer `%s' and  address '%s'\n",
2539                 GNUNET_i2s (&blc_ctx->address->peer), GST_plugins_a2s (blc_ctx->address));
2540     GNUNET_ATS_address_destroyed (GST_ats, blc_ctx->address, NULL);
2541     return;
2542   }
2543   switch (n->state)
2544   {
2545   case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
2546     GNUNET_break (0);
2547     free_neighbour (n, GNUNET_NO);
2548     return;
2549   case GNUNET_TRANSPORT_PS_INIT_ATS:
2550     set_primary_address (n, blc_ctx->address, blc_ctx->session,
2551         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out, GNUNET_NO);
2552     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_BLACKLIST,
2553         GNUNET_TIME_relative_to_absolute (BLACKLIST_RESPONSE_TIMEOUT));
2554     check_blacklist (&n->id, n->connect_ack_timestamp,
2555                      blc_ctx->address, blc_ctx->session);
2556     break;
2557   case GNUNET_TRANSPORT_PS_INIT_BLACKLIST:
2558     /* ATS suggests a different address, switch again */
2559     set_primary_address (n, blc_ctx->address, blc_ctx->session,
2560         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out, GNUNET_NO);
2561     set_timeout (n, GNUNET_TIME_relative_to_absolute (BLACKLIST_RESPONSE_TIMEOUT));
2562     check_blacklist (&n->id, n->connect_ack_timestamp,
2563                      blc_ctx->address, blc_ctx->session);
2564     break;
2565   case GNUNET_TRANSPORT_PS_CONNECT_SENT:
2566     /* ATS suggests a different address, switch again */
2567     set_primary_address (n, blc_ctx->address, blc_ctx->session,
2568         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out, GNUNET_NO);
2569     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_BLACKLIST,
2570         GNUNET_TIME_relative_to_absolute (BLACKLIST_RESPONSE_TIMEOUT));
2571     check_blacklist (&n->id, n->connect_ack_timestamp,
2572                      blc_ctx->address, blc_ctx->session);
2573     break;
2574   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS:
2575     set_primary_address (n, blc_ctx->address, blc_ctx->session,
2576         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out, GNUNET_NO);
2577     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST,
2578         GNUNET_TIME_relative_to_absolute (BLACKLIST_RESPONSE_TIMEOUT));
2579     check_blacklist (&n->id, n->connect_ack_timestamp,
2580         blc_ctx->address, blc_ctx->session);
2581     break;
2582   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND:
2583     set_timeout (n, GNUNET_TIME_relative_to_absolute (BLACKLIST_RESPONSE_TIMEOUT));
2584     check_blacklist (&n->id, n->connect_ack_timestamp,
2585         blc_ctx->address, blc_ctx->session);
2586     break;
2587   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST:
2588   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK:
2589     /* ATS asks us to switch while we were trying to connect; switch to new
2590        address and check blacklist again */
2591     set_primary_address (n, blc_ctx->address, blc_ctx->session,
2592         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out, GNUNET_NO);
2593     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST,
2594         GNUNET_TIME_relative_to_absolute (BLACKLIST_RESPONSE_TIMEOUT));
2595     check_blacklist (&n->id, n->connect_ack_timestamp,
2596         blc_ctx->address, blc_ctx->session);
2597     break;
2598   case GNUNET_TRANSPORT_PS_CONNECTED:
2599     GNUNET_assert (NULL != n->primary_address.address);
2600     GNUNET_assert (NULL != n->primary_address.session);
2601     if (n->primary_address.session == blc_ctx->session)
2602     {
2603       /* not an address change, just a quota change */
2604       set_primary_address (n, blc_ctx->address, blc_ctx->session,
2605           blc_ctx->bandwidth_in, blc_ctx->bandwidth_out, GNUNET_YES);
2606       break;
2607     }
2608     /* ATS asks us to switch a life connection; see if we can get
2609        a CONNECT_ACK on it before we actually do this! */
2610     set_state (n, GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST);
2611     set_alternative_address (n, blc_ctx->address, blc_ctx->session,
2612         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out);
2613     check_blacklist (&n->id, GNUNET_TIME_absolute_get (),
2614         blc_ctx->address, blc_ctx->session);
2615     break;
2616   case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
2617     set_primary_address (n, blc_ctx->address, blc_ctx->session,
2618         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out, GNUNET_NO);
2619     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST,
2620         GNUNET_TIME_relative_to_absolute (BLACKLIST_RESPONSE_TIMEOUT));
2621     check_blacklist (&n->id, n->connect_ack_timestamp,
2622         blc_ctx->address, blc_ctx->session);
2623     break;
2624   case GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST:
2625     /* ATS asks us to switch while we were trying to reconnect; switch to new
2626        address and check blacklist again */
2627     set_primary_address (n, blc_ctx->address, blc_ctx->session,
2628         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out, GNUNET_NO);
2629     set_timeout (n, GNUNET_TIME_relative_to_absolute (BLACKLIST_RESPONSE_TIMEOUT));
2630     check_blacklist (&n->id, n->connect_ack_timestamp,
2631         blc_ctx->address, blc_ctx->session);
2632     break;
2633   case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
2634     /* ATS asks us to switch while we were trying to reconnect; switch to new
2635        address and check blacklist again */
2636     set_primary_address (n, blc_ctx->address, blc_ctx->session,
2637         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out, GNUNET_NO);
2638     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST,
2639         GNUNET_TIME_relative_to_absolute (BLACKLIST_RESPONSE_TIMEOUT));
2640     check_blacklist (&n->id, n->connect_ack_timestamp,
2641         blc_ctx->address, blc_ctx->session);
2642     break;
2643   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST:
2644     if (n->primary_address.session == blc_ctx->session)
2645     {
2646       /* ATS switches back to still-active session */
2647       set_state(n, GNUNET_TRANSPORT_PS_CONNECTED);
2648       free_address (&n->alternative_address);
2649       break;
2650     }
2651     /* ATS asks us to switch a life connection, update blacklist check */
2652     set_primary_address (n, blc_ctx->address, blc_ctx->session,
2653         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out, GNUNET_NO);
2654     check_blacklist (&n->id, GNUNET_TIME_absolute_get (),
2655         blc_ctx->address, blc_ctx->session);
2656     break;
2657   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT:
2658     if (n->primary_address.session == blc_ctx->session)
2659     {
2660       /* ATS switches back to still-active session */
2661       free_address (&n->alternative_address);
2662       set_state (n, GNUNET_TRANSPORT_PS_CONNECTED);
2663       break;
2664     }
2665     /* ATS asks us to switch a life connection, update blacklist check */
2666     set_state (n, GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST);
2667     set_alternative_address (n, blc_ctx->address, blc_ctx->session,
2668         blc_ctx->bandwidth_in, blc_ctx->bandwidth_out);
2669     check_blacklist (&n->id, GNUNET_TIME_absolute_get (),
2670         blc_ctx->address, blc_ctx->session);
2671     break;
2672   case GNUNET_TRANSPORT_PS_DISCONNECT:
2673     /* not going to switch addresses while disconnecting */
2674     return;
2675   case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
2676     GNUNET_assert (0);
2677     break;
2678   default:
2679     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2680                 "Unhandled state `%s'\n",
2681                 GNUNET_TRANSPORT_ps2s (n->state));
2682     GNUNET_break (0);
2683     break;
2684   }
2685
2686   GNUNET_CONTAINER_DLL_remove (pending_bc_head, pending_bc_tail, blc_ctx);
2687   GNUNET_HELLO_address_free(blc_ctx->address);
2688   GNUNET_free_non_null (blc_ctx->ats);
2689   GNUNET_free (blc_ctx);
2690   return;
2691 }
2692
2693
2694 /**
2695  * For the given peer, switch to this address.
2696  *
2697  * Before accepting this addresses and actively using it, a blacklist check
2698  * is performed. If this blacklist check fails the address will be destroyed.
2699  *
2700  * @param peer identity of the peer to switch the address for
2701  * @param address address of the other peer,
2702  * @param session session to use or NULL if transport should initiate a session
2703  * @param ats performance data
2704  * @param ats_count number of entries in ats
2705  * @param bandwidth_in inbound quota to be used when connection is up,
2706  *      0 to disconnect from peer
2707  * @param bandwidth_out outbound quota to be used when connection is up,
2708  *      0 to disconnect from peer
2709  */
2710 void
2711 GST_neighbours_switch_to_address (const struct GNUNET_PeerIdentity *peer,
2712                                   const struct GNUNET_HELLO_Address *address,
2713                                   struct Session *session,
2714                                   const struct GNUNET_ATS_Information *ats,
2715                                   uint32_t ats_count,
2716                                   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
2717                                   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
2718 {
2719   struct NeighbourMapEntry *n;
2720   struct GST_BlacklistCheck *blc;
2721   struct GNUNET_TRANSPORT_PluginFunctions *papi;
2722   struct BlacklistCheckSwitchContext *blc_ctx;
2723   int c;
2724
2725   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2726               "ATS has decided on an address for peer %s\n",
2727               GNUNET_i2s (peer));
2728   GNUNET_assert (NULL != address->transport_name);
2729   if (NULL == (n = lookup_neighbour (peer)))
2730   {
2731     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2732                 "Peer %s is unknown, suggestion ignored\n",
2733                 GNUNET_i2s (peer));
2734     return;
2735   }
2736
2737   /* Obtain an session for this address from plugin */
2738   if (NULL == (papi = GST_plugins_find (address->transport_name)))
2739   {
2740     /* we don't have the plugin for this address */
2741     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2742                 "Plugin `%s' is unknown, suggestion for peer %s ignored\n",
2743                 address->transport_name,
2744                 GNUNET_i2s (peer));
2745     GNUNET_ATS_address_destroyed (GST_ats, address, NULL);
2746     return;
2747   }
2748   if ((NULL == session) &&
2749       (GNUNET_HELLO_address_check_option (address, GNUNET_HELLO_ADDRESS_INFO_INBOUND)))
2750   {
2751     /* This is a inbound address and we do not have a session to use! */
2752     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2753                 "Inbound address without session `%s'! Destroying address...\n",
2754                 GST_plugins_a2s (address));
2755     GNUNET_ATS_address_destroyed (GST_ats, address, NULL);
2756     return;
2757   }
2758
2759   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2760     "ATS tells us to switch to %s address '%s' session %p for "
2761     "peer `%s' in state %s/%d (quota in/out %u %u )\n",
2762     GNUNET_HELLO_address_check_option (address,
2763         GNUNET_HELLO_ADDRESS_INFO_INBOUND) ? "inbound" : "",
2764     GST_plugins_a2s (address), session, GNUNET_i2s (peer),
2765     GNUNET_TRANSPORT_ps2s (n->state), n->send_connect_ack,
2766     ntohl (bandwidth_in.value__), ntohl (bandwidth_out.value__));
2767
2768   /* Perform blacklist check */
2769   blc_ctx = GNUNET_new (struct BlacklistCheckSwitchContext);
2770   blc_ctx->address = GNUNET_HELLO_address_copy (address);
2771   blc_ctx->session = session;
2772   blc_ctx->bandwidth_in = bandwidth_in;
2773   blc_ctx->bandwidth_out = bandwidth_out;
2774   blc_ctx->ats_count = ats_count;
2775   blc_ctx->ats = NULL;
2776   if (ats_count > 0)
2777   {
2778     blc_ctx->ats = GNUNET_malloc (ats_count * sizeof (struct GNUNET_ATS_Information));
2779     for (c = 0; c < ats_count; c++)
2780     {
2781       blc_ctx->ats[c].type = ats[c].type;
2782       blc_ctx->ats[c].value = ats[c].value;
2783     }
2784   }
2785
2786   GNUNET_CONTAINER_DLL_insert (pending_bc_head, pending_bc_tail, blc_ctx);
2787   if (NULL != (blc = GST_blacklist_test_allowed (peer, address->transport_name,
2788       &switch_address_bl_check_cont, blc_ctx)))
2789   {
2790     blc_ctx->blc = blc;
2791   }
2792 }
2793
2794
2795 static int
2796 send_utilization_data (void *cls,
2797                        const struct GNUNET_PeerIdentity *key,
2798                        void *value)
2799 {
2800   struct NeighbourMapEntry *n = value;
2801   struct GNUNET_ATS_Information atsi[4];
2802   uint32_t bps_pl_in;
2803   uint32_t bps_pl_out;
2804   uint32_t bps_in;
2805   uint32_t bps_out;
2806   struct GNUNET_TIME_Relative delta;
2807
2808   delta = GNUNET_TIME_absolute_get_difference (n->last_util_transmission,
2809                                                GNUNET_TIME_absolute_get ());
2810
2811   bps_pl_in = 0;
2812
2813   if ((0 != n->util_payload_bytes_recv) && (0 != delta.rel_value_us))
2814     bps_pl_in =  (1000LL * 1000LL *  n->util_payload_bytes_recv) / (delta.rel_value_us);
2815   bps_pl_out = 0;
2816   if ((0 != n->util_payload_bytes_sent) && (0 != delta.rel_value_us))
2817     bps_pl_out = (1000LL * 1000LL * n->util_payload_bytes_sent) / delta.rel_value_us;
2818   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2819               "`%s' payload: received %u Bytes/s, sent %u Bytes/s\n",
2820               GNUNET_i2s (key),
2821               bps_pl_in,
2822               bps_pl_out);
2823   bps_in = 0;
2824   if ((0 != n->util_total_bytes_recv) && (0 != delta.rel_value_us))
2825     bps_in =  (1000LL * 1000LL *  n->util_total_bytes_recv) / (delta.rel_value_us);
2826   bps_out = 0;
2827   if ((0 != n->util_total_bytes_sent) && (0 != delta.rel_value_us))
2828     bps_out = (1000LL * 1000LL * n->util_total_bytes_sent) / delta.rel_value_us;
2829
2830
2831   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2832               "`%s' total: received %u Bytes/s, sent %u Bytes/s\n",
2833               GNUNET_i2s (key),
2834               bps_in,
2835               bps_out);
2836   atsi[0].type = htonl (GNUNET_ATS_UTILIZATION_OUT);
2837   atsi[0].value = htonl (bps_out);
2838   atsi[1].type = htonl (GNUNET_ATS_UTILIZATION_IN);
2839   atsi[1].value = htonl (bps_in);
2840
2841   atsi[2].type = htonl (GNUNET_ATS_UTILIZATION_PAYLOAD_OUT);
2842   atsi[2].value = htonl (bps_pl_out);
2843   atsi[3].type = htonl (GNUNET_ATS_UTILIZATION_PAYLOAD_IN);
2844   atsi[3].value = htonl (bps_pl_in);
2845
2846   GST_ats_update_metrics (key, n->primary_address.address,
2847       n->primary_address.session, atsi, 4);
2848   n->util_payload_bytes_recv = 0;
2849   n->util_payload_bytes_sent = 0;
2850   n->util_total_bytes_recv = 0;
2851   n->util_total_bytes_sent = 0;
2852   n->last_util_transmission = GNUNET_TIME_absolute_get();
2853   return GNUNET_OK;
2854 }
2855
2856
2857 /**
2858  * Task transmitting utilization in a regular interval
2859  *
2860  * @param cls the 'struct NeighbourMapEntry' for which we are running
2861  * @param tc scheduler context (unused)
2862  */
2863 static void
2864 utilization_transmission (void *cls,
2865                           const struct GNUNET_SCHEDULER_TaskContext *tc)
2866 {
2867   util_transmission_tk = GNUNET_SCHEDULER_NO_TASK;
2868
2869   if (0 < GNUNET_CONTAINER_multipeermap_size (neighbours))
2870     GNUNET_CONTAINER_multipeermap_iterate (neighbours, send_utilization_data, NULL);
2871
2872   util_transmission_tk = GNUNET_SCHEDULER_add_delayed (UTIL_TRANSMISSION_INTERVAL,
2873       utilization_transmission, NULL);
2874
2875 }
2876
2877
2878 void
2879 GST_neighbours_notify_data_recv (const struct GNUNET_PeerIdentity *peer,
2880                                  const struct GNUNET_HELLO_Address *address,
2881                                  struct Session *session,
2882                                  const struct GNUNET_MessageHeader *message)
2883 {
2884   struct NeighbourMapEntry *n;
2885
2886   n = lookup_neighbour (peer);
2887   if (NULL == n)
2888     return;
2889   n->util_total_bytes_recv += ntohs(message->size);
2890 }
2891
2892
2893 void
2894 GST_neighbours_notify_payload_recv (const struct GNUNET_PeerIdentity *peer,
2895                                     const struct GNUNET_HELLO_Address *address,
2896                                     struct Session *session,
2897                                     const struct GNUNET_MessageHeader *message)
2898 {
2899   struct NeighbourMapEntry *n;
2900   n = lookup_neighbour (peer);
2901   if (NULL == n)
2902     return;
2903   n->util_payload_bytes_recv += ntohs(message->size);
2904 }
2905
2906
2907 void
2908 GST_neighbours_notify_data_sent (const struct GNUNET_PeerIdentity *peer,
2909                                  const struct GNUNET_HELLO_Address *address,
2910                                  struct Session *session,
2911                                  size_t size)
2912 {
2913   struct NeighbourMapEntry *n;
2914   n = lookup_neighbour (peer);
2915   if (NULL == n)
2916       return;
2917   if (n->primary_address.session != session)
2918     return;
2919   n->util_total_bytes_sent += size;
2920 }
2921
2922
2923 void
2924 GST_neighbours_notify_payload_sent (const struct GNUNET_PeerIdentity *peer,
2925                                     size_t size)
2926 {
2927   struct NeighbourMapEntry *n;
2928   n = lookup_neighbour (peer);
2929   if (NULL == n)
2930     return;
2931   n->util_payload_bytes_sent += size;
2932 }
2933
2934
2935 /**
2936  * Master task run for every neighbour.  Performs all of the time-related
2937  * activities (keep alive, send next message, disconnect if idle, finish
2938  * clean up after disconnect).
2939  *
2940  * @param cls the 'struct NeighbourMapEntry' for which we are running
2941  * @param tc scheduler context (unused)
2942  */
2943 static void
2944 master_task (void *cls,
2945              const struct GNUNET_SCHEDULER_TaskContext *tc)
2946 {
2947   struct NeighbourMapEntry *n = cls;
2948   struct GNUNET_TIME_Relative delay;
2949
2950   n->task = GNUNET_SCHEDULER_NO_TASK;
2951   delay = GNUNET_TIME_absolute_get_remaining (n->timeout);
2952   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2953               "Master task runs for neighbour `%s' in state %s with timeout in %s\n",
2954               GNUNET_i2s (&n->id),
2955               GNUNET_TRANSPORT_ps2s(n->state),
2956               GNUNET_STRINGS_relative_time_to_string (delay,
2957                                                       GNUNET_YES));
2958   switch (n->state)
2959   {
2960   case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
2961     /* invalid state for master task, clean up */
2962     GNUNET_break (0);
2963     set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED);
2964     free_neighbour (n, GNUNET_NO);
2965     return;
2966   case GNUNET_TRANSPORT_PS_INIT_ATS:
2967     if (0 == delay.rel_value_us)
2968     {
2969       GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2970                   "Connection to `%s' timed out waiting for ATS to provide address\n",
2971                   GNUNET_i2s (&n->id));
2972       set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED);
2973       free_neighbour (n, GNUNET_NO);
2974       return;
2975     }
2976     break;
2977   case GNUNET_TRANSPORT_PS_INIT_BLACKLIST:
2978     if (0 == delay.rel_value_us)
2979     {
2980       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2981                   "Connection to `%s' timed out waiting for BLACKLIST to approve address\n",
2982                   GNUNET_i2s (&n->id));
2983       set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED);
2984       free_neighbour (n, GNUNET_NO);
2985       return;
2986     }
2987     break;
2988   case GNUNET_TRANSPORT_PS_CONNECT_SENT:
2989     if (0 == delay.rel_value_us)
2990     {
2991       GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2992                   "Connection to `%s' timed out waiting for other peer to send CONNECT_ACK\n",
2993                   GNUNET_i2s (&n->id));
2994       /* We could not send to this address, delete address and session */
2995       if (NULL != n->primary_address.session)
2996         GNUNET_ATS_address_destroyed (GST_ats,
2997             n->primary_address.address, n->primary_address.session);
2998       GNUNET_ATS_address_destroyed (GST_ats,
2999           n->primary_address.address, NULL);
3000       disconnect_neighbour (n);
3001       return;
3002     }
3003     break;
3004   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND:
3005     if (0 == delay.rel_value_us)
3006     {
3007       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3008                   "Connection to `%s' timed out waiting BLACKLIST to approve address to use for received CONNECT\n",
3009                   GNUNET_i2s (&n->id));
3010       set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED);
3011       free_neighbour (n, GNUNET_NO);
3012       return;
3013     }
3014     break;
3015   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS:
3016     if (0 == delay.rel_value_us)
3017     {
3018       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3019                   "Connection to `%s' timed out waiting ATS to provide address to use for CONNECT_ACK\n",
3020                   GNUNET_i2s (&n->id));
3021       set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED);
3022       free_neighbour (n, GNUNET_NO);
3023       return;
3024     }
3025     break;
3026   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST:
3027     if (0 == delay.rel_value_us)
3028     {
3029       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3030                   "Connection to `%s' timed out waiting BLACKLIST to approve address to use for CONNECT_ACK\n",
3031                   GNUNET_i2s (&n->id));
3032       set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED);
3033       free_neighbour (n, GNUNET_NO);
3034       return;
3035     }
3036     break;
3037   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK:
3038     if (0 == delay.rel_value_us)
3039     {
3040       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3041                   "Connection to `%s' timed out waiting for other peer to send SESSION_ACK\n",
3042                   GNUNET_i2s (&n->id));
3043       disconnect_neighbour (n);
3044       return;
3045     }
3046     break;
3047   case GNUNET_TRANSPORT_PS_CONNECTED:
3048     if (0 == delay.rel_value_us)
3049     {
3050       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3051                   "Connection to `%s' timed out, missing KEEPALIVE_RESPONSEs\n",
3052                   GNUNET_i2s (&n->id));
3053       disconnect_neighbour (n);
3054       return;
3055     }
3056     try_transmission_to_peer (n);
3057     send_keepalive (n);
3058     break;
3059   case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
3060     if (0 == delay.rel_value_us)
3061     {
3062       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3063                   "Connection to `%s' timed out, waiting for ATS replacement address\n",
3064                   GNUNET_i2s (&n->id));
3065       disconnect_neighbour (n);
3066       return;
3067     }
3068     break;
3069   case GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST:
3070     if (0 == delay.rel_value_us)
3071     {
3072       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3073                   "Connection to `%s' timed out, waiting for BLACKLIST to approve replacement address\n",
3074                   GNUNET_i2s (&n->id));
3075       disconnect_neighbour (n);
3076       return;
3077     }
3078     break;
3079   case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
3080     if (0 == delay.rel_value_us)
3081     {
3082       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3083                   "Connection to `%s' timed out, waiting for other peer to CONNECT_ACK replacement address\n",
3084                   GNUNET_i2s (&n->id));
3085       disconnect_neighbour (n);
3086       return;
3087     }
3088     break;
3089   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST:
3090     if (0 == delay.rel_value_us)
3091     {
3092       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3093                   "Connection to `%s' timed out, missing KEEPALIVE_RESPONSEs\n",
3094                   GNUNET_i2s (&n->id));
3095       disconnect_neighbour (n);
3096       return;
3097     }
3098     try_transmission_to_peer (n);
3099     send_keepalive (n);
3100     break;
3101   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT:
3102     if (0 == delay.rel_value_us)
3103     {
3104       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3105                   "Connection to `%s' timed out, missing KEEPALIVE_RESPONSEs (after trying to CONNECT on alternative address)\n",
3106                   GNUNET_i2s (&n->id));
3107       disconnect_neighbour (n);
3108       return;
3109     }
3110     try_transmission_to_peer (n);
3111     send_keepalive (n);
3112     break;
3113   case GNUNET_TRANSPORT_PS_DISCONNECT:
3114     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3115                 "Cleaning up connection to `%s' after sending DISCONNECT\n",
3116                 GNUNET_i2s (&n->id));
3117     free_neighbour (n, GNUNET_NO);
3118     return;
3119   case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
3120     /* how did we get here!? */
3121     GNUNET_assert (0);
3122     break;
3123   default:
3124     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3125                 "Unhandled state `%s'\n",
3126                 GNUNET_TRANSPORT_ps2s (n->state));
3127     GNUNET_break (0);
3128     break;
3129   }
3130   if ( (GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT == n->state) ||
3131        (GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST == n->state) ||
3132        (GNUNET_TRANSPORT_PS_CONNECTED == n->state) )
3133   {
3134     /* if we are *now* in one of these three states, we're sending
3135        keep alive messages, so we need to consider the keepalive
3136        delay, not just the connection timeout */
3137     delay = GNUNET_TIME_relative_min (GNUNET_TIME_absolute_get_remaining (n->keep_alive_time),
3138                                       delay);
3139   }
3140   if (GNUNET_SCHEDULER_NO_TASK == n->task)
3141     n->task = GNUNET_SCHEDULER_add_delayed (delay,
3142                                             &master_task,
3143                                             n);
3144 }
3145
3146
3147 /**
3148  * Send a SESSION_ACK message to the neighbour to confirm that we
3149  * got his CONNECT_ACK.
3150  *
3151  * @param n neighbour to send the SESSION_ACK to
3152  */
3153 static void
3154 send_session_ack_message (struct NeighbourMapEntry *n)
3155 {
3156   struct GNUNET_MessageHeader msg;
3157
3158   msg.size = htons (sizeof (struct GNUNET_MessageHeader));
3159   msg.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_ACK);
3160   (void) send_with_session(n,
3161                            (const char *) &msg, sizeof (struct GNUNET_MessageHeader),
3162                            UINT32_MAX, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_NO,
3163                            NULL, NULL);
3164 }
3165
3166
3167 /**
3168  * We received a 'SESSION_CONNECT_ACK' message from the other peer.
3169  * Consider switching to it.
3170  *
3171  * @param message possibly a 'struct SessionConnectMessage' (check format)
3172  * @param peer identity of the peer to switch the address for
3173  * @param address address of the other peer, NULL if other peer
3174  *                       connected to us
3175  * @param session session to use (or NULL)
3176  * @return #GNUNET_OK if the message was fine, #GNUNET_SYSERR on serious error
3177  */
3178 int
3179 GST_neighbours_handle_connect_ack (const struct GNUNET_MessageHeader *message,
3180                                    const struct GNUNET_PeerIdentity *peer,
3181                                    const struct GNUNET_HELLO_Address *address,
3182                                    struct Session *session)
3183 {
3184   const struct SessionConnectMessage *scm;
3185   struct GNUNET_TIME_Absolute ts;
3186   struct NeighbourMapEntry *n;
3187
3188   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3189               "Received CONNECT_ACK message from peer `%s'\n",
3190               GNUNET_i2s (peer));
3191
3192   if (ntohs (message->size) != sizeof (struct SessionConnectMessage))
3193   {
3194     GNUNET_break_op (0);
3195     return GNUNET_SYSERR;
3196   }
3197   GNUNET_STATISTICS_update (GST_stats,
3198                             gettext_noop
3199                             ("# CONNECT_ACK messages received"),
3200                             1, GNUNET_NO);
3201   scm = (const struct SessionConnectMessage *) message;
3202   GNUNET_break_op (ntohl (scm->reserved) == 0);
3203   if (NULL == (n = lookup_neighbour (peer)))
3204   {
3205     GNUNET_STATISTICS_update (GST_stats,
3206                               gettext_noop
3207                               ("# unexpected CONNECT_ACK messages (no peer)"),
3208                               1, GNUNET_NO);
3209     return GNUNET_SYSERR;
3210   }
3211   ts = GNUNET_TIME_absolute_ntoh (scm->timestamp);
3212   switch (n->state)
3213   {
3214   case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
3215     GNUNET_break (0);
3216     free_neighbour (n, GNUNET_NO);
3217     return GNUNET_SYSERR;
3218   case GNUNET_TRANSPORT_PS_INIT_ATS:
3219   case GNUNET_TRANSPORT_PS_INIT_BLACKLIST:
3220     GNUNET_STATISTICS_update (GST_stats,
3221                               gettext_noop
3222                               ("# unexpected CONNECT_ACK messages (not ready)"),
3223                               1, GNUNET_NO);
3224     break;
3225   case GNUNET_TRANSPORT_PS_CONNECT_SENT:
3226     if (ts.abs_value_us != n->primary_address.connect_timestamp.abs_value_us)
3227     {
3228       GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3229                   "CONNECT_ACK ignored as the timestamp does not match our CONNECT request\n");
3230       return GNUNET_OK;
3231     }
3232     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT));
3233     GNUNET_STATISTICS_set (GST_stats,
3234                            gettext_noop ("# peers connected"),
3235                            ++neighbours_connected,
3236                            GNUNET_NO);
3237     connect_notify_cb (callback_cls, &n->id,
3238                        n->primary_address.bandwidth_in,
3239                        n->primary_address.bandwidth_out);
3240     /* Tell ATS that the outbound session we created to send CONNECT was successful */
3241     GST_ats_add_address (n->primary_address.address,
3242                          n->primary_address.session,
3243                          NULL, 0);
3244     set_primary_address (n,
3245                  n->primary_address.address,
3246                  n->primary_address.session,
3247                  n->primary_address.bandwidth_in,
3248                  n->primary_address.bandwidth_out,
3249                  GNUNET_YES);
3250     send_session_ack_message (n);
3251     break;
3252   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND:
3253   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS:
3254   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST:
3255   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK:
3256     GNUNET_STATISTICS_update (GST_stats,
3257                               gettext_noop
3258                               ("# unexpected CONNECT_ACK messages (not ready)"),
3259                               1, GNUNET_NO);
3260     break;
3261   case GNUNET_TRANSPORT_PS_CONNECTED:
3262     /* duplicate CONNECT_ACK, let's answer by duplciate SESSION_ACK just in case */
3263     send_session_ack_message (n);
3264     break;
3265   case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
3266   case GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST:
3267     /* we didn't expect any CONNECT_ACK, as we are waiting for ATS
3268        to give us a new address... */
3269     GNUNET_STATISTICS_update (GST_stats,
3270                               gettext_noop
3271                               ("# unexpected CONNECT_ACK messages (waiting on ATS)"),
3272                               1, GNUNET_NO);
3273     break;
3274   case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
3275     /* new address worked; go back to connected! */
3276     set_state (n, GNUNET_TRANSPORT_PS_CONNECTED);
3277     send_session_ack_message (n);
3278     break;
3279   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST:
3280     /* duplicate CONNECT_ACK, let's answer by duplciate SESSION_ACK just in case */
3281     send_session_ack_message (n);
3282     break;
3283   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT:
3284     /* new address worked; adopt it and go back to connected! */
3285     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT));
3286     GNUNET_break (GNUNET_NO == n->alternative_address.ats_active);
3287
3288     GST_ats_add_address (n->alternative_address.address,
3289                          n->alternative_address.session,
3290                          NULL, 0);
3291     set_primary_address (n, n->alternative_address.address,
3292         n->alternative_address.session, n->alternative_address.bandwidth_in,
3293         n->alternative_address.bandwidth_out, GNUNET_YES);
3294
3295     free_address (&n->alternative_address);
3296     send_session_ack_message (n);
3297     break;
3298   case GNUNET_TRANSPORT_PS_DISCONNECT:
3299     GNUNET_STATISTICS_update (GST_stats,
3300                               gettext_noop
3301                               ("# unexpected CONNECT_ACK messages (disconnecting)"),
3302                               1, GNUNET_NO);
3303     return GNUNET_SYSERR;
3304   case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
3305     GNUNET_assert (0);
3306     break;
3307   default:
3308     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3309                 "Unhandled state `%s'\n",
3310                 GNUNET_TRANSPORT_ps2s (n->state));
3311     GNUNET_break (0);
3312     return GNUNET_SYSERR;
3313   }
3314   return GNUNET_OK;
3315 }
3316
3317
3318 /**
3319  * A session was terminated. Take note; if needed, try to get
3320  * an alternative address from ATS.
3321  *
3322  * @param peer identity of the peer where the session died
3323  * @param session session that is gone
3324  * @return #GNUNET_YES if this was a session used, #GNUNET_NO if
3325  *        this session was not in use
3326  */
3327 int
3328 GST_neighbours_session_terminated (const struct GNUNET_PeerIdentity *peer,
3329                                    struct Session *session)
3330 {
3331   struct NeighbourMapEntry *n;
3332   struct BlackListCheckContext *bcc;
3333   struct BlackListCheckContext *bcc_next;
3334
3335   /* make sure to cancel all ongoing blacklist checks involving 'session' */
3336   bcc_next = bc_head;
3337   while (NULL != (bcc = bcc_next))
3338   {
3339     bcc_next = bcc->next;
3340     if (bcc->na.session == session)
3341     {
3342       if (NULL != bcc->bc)
3343         GST_blacklist_test_cancel (bcc->bc);
3344       GNUNET_HELLO_address_free (bcc->na.address);
3345       GNUNET_CONTAINER_DLL_remove (bc_head,
3346                                    bc_tail,
3347                                    bcc);
3348       GNUNET_free (bcc);
3349     }
3350   }
3351   if (NULL == (n = lookup_neighbour (peer)))
3352     return GNUNET_NO; /* can't affect us */
3353   if (session != n->primary_address.session)
3354   {
3355     if (session == n->alternative_address.session)
3356     {
3357       if ( (GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST == n->state) ||
3358            (GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT == n->state) )
3359         set_state (n, GNUNET_TRANSPORT_PS_CONNECTED);
3360       else
3361         GNUNET_break (0);
3362       free_address (&n->alternative_address);
3363     }
3364     return GNUNET_NO; /* doesn't affect us further */
3365   }
3366
3367   n->expect_latency_response = GNUNET_NO;
3368   switch (n->state)
3369   {
3370   case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
3371     GNUNET_break (0);
3372     free_neighbour (n, GNUNET_NO);
3373     return GNUNET_YES;
3374   case GNUNET_TRANSPORT_PS_INIT_ATS:
3375     GNUNET_break (0);
3376     free_neighbour (n, GNUNET_NO);
3377     return GNUNET_YES;
3378   case GNUNET_TRANSPORT_PS_INIT_BLACKLIST:
3379   case GNUNET_TRANSPORT_PS_CONNECT_SENT:
3380     free_address (&n->primary_address);
3381     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
3382     break;
3383   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND:
3384   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS:
3385   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST:
3386   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK:
3387     /* error on inbound session; free neighbour entirely */
3388     free_address (&n->primary_address);
3389     free_neighbour (n, GNUNET_NO);
3390     return GNUNET_YES;
3391   case GNUNET_TRANSPORT_PS_CONNECTED:
3392     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
3393     free_address (&n->primary_address);
3394     break;
3395   case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
3396     /* we don't have an address, how can it go down? */
3397     GNUNET_break (0);
3398     break;
3399   case GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST:
3400   case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
3401     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT));
3402     break;
3403   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST:
3404     /* primary went down while we were checking secondary against
3405        blacklist, adopt secondary as primary */
3406     free_address (&n->primary_address);
3407     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST, GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT));
3408     n->primary_address = n->alternative_address;
3409     memset (&n->alternative_address, 0, sizeof (struct NeighbourAddress));
3410     break;
3411   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT:
3412     /* primary went down while we were waiting for CONNECT_ACK on secondary;
3413        secondary as primary */
3414     free_address (&n->primary_address);
3415     n->primary_address = n->alternative_address;
3416     memset (&n->alternative_address, 0, sizeof (struct NeighbourAddress));
3417     set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_SENT, GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT));
3418     break;
3419   case GNUNET_TRANSPORT_PS_DISCONNECT:
3420     free_address (&n->primary_address);
3421     break;
3422   case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
3423     /* neighbour was freed and plugins told to terminate session */
3424     return GNUNET_NO;
3425     break;
3426   default:
3427     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3428                 "Unhandled state `%s'\n",
3429                 GNUNET_TRANSPORT_ps2s (n->state));
3430     GNUNET_break (0);
3431     break;
3432   }
3433   if (GNUNET_SCHEDULER_NO_TASK != n->task)
3434     GNUNET_SCHEDULER_cancel (n->task);
3435   n->task = GNUNET_SCHEDULER_add_now (&master_task, n);
3436   return GNUNET_YES;
3437 }
3438
3439
3440 /**
3441  * We received a 'SESSION_ACK' message from the other peer.
3442  * If we sent a 'CONNECT_ACK' last, this means we are now
3443  * connected.  Otherwise, do nothing.
3444  *
3445  * @param message possibly a 'struct SessionConnectMessage' (check format)
3446  * @param peer identity of the peer to switch the address for
3447  * @param address address of the other peer, NULL if other peer
3448  *                       connected to us
3449  * @param session session to use (or NULL)
3450  * @return #GNUNET_OK if the message was fine, #GNUNET_SYSERR on serious error
3451  */
3452 int
3453 GST_neighbours_handle_session_ack (const struct GNUNET_MessageHeader *message,
3454                                    const struct GNUNET_PeerIdentity *peer,
3455                                    const struct GNUNET_HELLO_Address *address,
3456                                    struct Session *session)
3457 {
3458   struct NeighbourMapEntry *n;
3459
3460   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3461               "Received SESSION_ACK message from peer `%s'\n",
3462               GNUNET_i2s (peer));
3463   if (ntohs (message->size) != sizeof (struct GNUNET_MessageHeader))
3464   {
3465     GNUNET_break_op (0);
3466     return GNUNET_SYSERR;
3467   }
3468   GNUNET_STATISTICS_update (GST_stats,
3469                             gettext_noop
3470                             ("# SESSION_ACK messages received"),
3471                             1, GNUNET_NO);
3472   if (NULL == (n = lookup_neighbour (peer)))
3473   {
3474     GNUNET_break_op (0);
3475     return GNUNET_SYSERR;
3476   }
3477   /* check if we are in a plausible state for having sent
3478      a CONNECT_ACK.  If not, return, otherwise break */
3479   if ( ( (GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK != n->state) &&
3480          (GNUNET_TRANSPORT_PS_CONNECT_SENT != n->state) ) ||
3481        (2 != n->send_connect_ack) )
3482   {
3483     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3484                 "Received SESSION_ACK message from peer `%s' in state %s/%d\n",
3485                 GNUNET_i2s (peer),
3486                 GNUNET_TRANSPORT_ps2s (n->state),
3487                 n->send_connect_ack);
3488     GNUNET_STATISTICS_update (GST_stats,
3489                               gettext_noop ("# unexpected SESSION_ACK messages"), 1,
3490                               GNUNET_NO);
3491     return GNUNET_OK;
3492   }
3493   set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT));
3494   GNUNET_STATISTICS_set (GST_stats,
3495                          gettext_noop ("# peers connected"),
3496                          ++neighbours_connected,
3497                          GNUNET_NO);
3498   connect_notify_cb (callback_cls, &n->id,
3499                      n->primary_address.bandwidth_in,
3500                      n->primary_address.bandwidth_out);
3501
3502   GST_ats_add_address (n->primary_address.address,
3503                        n->primary_address.session,
3504                        NULL, 0);
3505   set_primary_address (n,
3506                n->primary_address.address,
3507                n->primary_address.session,
3508                n->primary_address.bandwidth_in,
3509                n->primary_address.bandwidth_out,
3510                GNUNET_YES);
3511   return GNUNET_OK;
3512 }
3513
3514
3515 /**
3516  * Test if we're connected to the given peer.
3517  *
3518  * @param target peer to test
3519  * @return #GNUNET_YES if we are connected, #GNUNET_NO if not
3520  */
3521 int
3522 GST_neighbours_test_connected (const struct GNUNET_PeerIdentity *target)
3523 {
3524   return test_connected (lookup_neighbour (target));
3525 }
3526
3527 /**
3528  * Change the incoming quota for the given peer.
3529  *
3530  * @param neighbour identity of peer to change qutoa for
3531  * @param quota new quota
3532  */
3533 void
3534 GST_neighbours_set_incoming_quota (const struct GNUNET_PeerIdentity *neighbour,
3535                                    struct GNUNET_BANDWIDTH_Value32NBO quota)
3536 {
3537   struct NeighbourMapEntry *n;
3538
3539   if (NULL == (n = lookup_neighbour (neighbour)))
3540   {
3541     GNUNET_STATISTICS_update (GST_stats,
3542                               gettext_noop
3543                               ("# SET QUOTA messages ignored (no such peer)"),
3544                               1, GNUNET_NO);
3545     return;
3546   }
3547   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3548               "Setting inbound quota of %u Bps for peer `%s' to all clients\n",
3549               ntohl (quota.value__), GNUNET_i2s (&n->id));
3550   GNUNET_BANDWIDTH_tracker_update_quota (&n->in_tracker, quota);
3551   if (0 != ntohl (quota.value__))
3552     return;
3553   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3554               "Disconnecting peer `%4s' due to SET_QUOTA\n",
3555               GNUNET_i2s (&n->id));
3556   if (GNUNET_YES == test_connected (n))
3557     GNUNET_STATISTICS_update (GST_stats,
3558                               gettext_noop ("# disconnects due to quota of 0"),
3559                               1, GNUNET_NO);
3560   disconnect_neighbour (n);
3561 }
3562
3563
3564 /**
3565  * We received a disconnect message from the given peer,
3566  * validate and process.
3567  *
3568  * @param peer sender of the message
3569  * @param msg the disconnect message
3570  */
3571 void
3572 GST_neighbours_handle_disconnect_message (const struct GNUNET_PeerIdentity *peer,
3573                                           const struct GNUNET_MessageHeader *msg)
3574 {
3575   struct NeighbourMapEntry *n;
3576   const struct SessionDisconnectMessage *sdm;
3577
3578   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3579               "Received DISCONNECT message from peer `%s'\n",
3580               GNUNET_i2s (peer));
3581   if (ntohs (msg->size) != sizeof (struct SessionDisconnectMessage))
3582   {
3583     // GNUNET_break_op (0);
3584     GNUNET_STATISTICS_update (GST_stats,
3585                               gettext_noop
3586                               ("# disconnect messages ignored (old format)"), 1,
3587                               GNUNET_NO);
3588     return;
3589   }
3590   GNUNET_STATISTICS_update (GST_stats,
3591                             gettext_noop
3592                             ("# DISCONNECT messages received"),
3593                             1, GNUNET_NO);
3594   sdm = (const struct SessionDisconnectMessage *) msg;
3595   if (NULL == (n = lookup_neighbour (peer)))
3596     return;                     /* gone already */
3597   if (GNUNET_TIME_absolute_ntoh (sdm->timestamp).abs_value_us <= n->connect_ack_timestamp.abs_value_us)
3598   {
3599     GNUNET_STATISTICS_update (GST_stats,
3600                               gettext_noop
3601                               ("# disconnect messages ignored (timestamp)"), 1,
3602                               GNUNET_NO);
3603     return;
3604   }
3605   if (0 != memcmp (peer, &sdm->public_key, sizeof (struct GNUNET_PeerIdentity)))
3606   {
3607     GNUNET_break_op (0);
3608     return;
3609   }
3610   if (ntohl (sdm->purpose.size) !=
3611       sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
3612       sizeof (struct GNUNET_CRYPTO_EddsaPublicKey) +
3613       sizeof (struct GNUNET_TIME_AbsoluteNBO))
3614   {
3615     GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3616                 "%s message from peer `%s' has invalid size \n",
3617                 "DISCONNECT",
3618                 GNUNET_i2s (peer));
3619     GNUNET_break_op (0);
3620     return;
3621   }
3622   if (GNUNET_OK !=
3623       GNUNET_CRYPTO_eddsa_verify
3624       (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT, &sdm->purpose,
3625        &sdm->signature, &sdm->public_key))
3626   {
3627     GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3628                 "%s message from peer `%s' cannot be verified \n",
3629                 "DISCONNECT",
3630                 GNUNET_i2s (peer));
3631     GNUNET_break_op (0);
3632     return;
3633   }
3634   if (GNUNET_YES == test_connected (n))
3635     GNUNET_STATISTICS_update (GST_stats,
3636                               gettext_noop
3637                               ("# other peer asked to disconnect from us"), 1,
3638                               GNUNET_NO);
3639   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3640               "Disconnecting by request from peer %s\n",
3641               GNUNET_i2s (peer));
3642   disconnect_neighbour (n);
3643 }
3644
3645
3646 /**
3647  * Closure for the neighbours_iterate function.
3648  */
3649 struct IteratorContext
3650 {
3651   /**
3652    * Function to call on each connected neighbour.
3653    */
3654   GST_NeighbourIterator cb;
3655
3656   /**
3657    * Closure for 'cb'.
3658    */
3659   void *cb_cls;
3660 };
3661
3662
3663 /**
3664  * Call the callback from the closure for each neighbour.
3665  *
3666  * @param cls the `struct IteratorContext`
3667  * @param key the hash of the public key of the neighbour
3668  * @param value the `struct NeighbourMapEntry`
3669  * @return #GNUNET_OK (continue to iterate)
3670  */
3671 static int
3672 neighbours_iterate (void *cls,
3673                     const struct GNUNET_PeerIdentity *key,
3674                     void *value)
3675 {
3676   struct IteratorContext *ic = cls;
3677   struct NeighbourMapEntry *n = value;
3678   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in;
3679   struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out;
3680
3681
3682   if (NULL != n->primary_address.address)
3683   {
3684     bandwidth_in = n->primary_address.bandwidth_in;
3685     bandwidth_out = n->primary_address.bandwidth_out;
3686   }
3687   else
3688   {
3689     bandwidth_in = GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT;
3690     bandwidth_out = GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT;
3691   }
3692   ic->cb (ic->cb_cls,
3693           &n->id,
3694           n->primary_address.address,
3695           n->state,
3696           n->timeout,
3697           bandwidth_in, bandwidth_out);
3698   return GNUNET_OK;
3699 }
3700
3701
3702 /**
3703  * Iterate over all connected neighbours.
3704  *
3705  * @param cb function to call
3706  * @param cb_cls closure for cb
3707  */
3708 void
3709 GST_neighbours_iterate (GST_NeighbourIterator cb, void *cb_cls)
3710 {
3711   struct IteratorContext ic;
3712
3713   if (NULL == neighbours)
3714     return; /* can happen during shutdown */
3715   ic.cb = cb;
3716   ic.cb_cls = cb_cls;
3717   GNUNET_CONTAINER_multipeermap_iterate (neighbours, &neighbours_iterate, &ic);
3718 }
3719
3720
3721 /**
3722  * If we have an active connection to the given target, it must be shutdown.
3723  *
3724  * @param target peer to disconnect from
3725  */
3726 void
3727 GST_neighbours_force_disconnect (const struct GNUNET_PeerIdentity *target)
3728 {
3729   struct NeighbourMapEntry *n;
3730
3731   if (NULL == (n = lookup_neighbour (target)))
3732     return;  /* not active */
3733   if (GNUNET_YES == test_connected (n))
3734     GNUNET_STATISTICS_update (GST_stats,
3735                               gettext_noop
3736                               ("# disconnected from peer upon explicit request"), 1,
3737                               GNUNET_NO);
3738   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3739               "Forced disconnect from peer %s\n",
3740               GNUNET_i2s (target));
3741   disconnect_neighbour (n);
3742 }
3743
3744
3745 /**
3746  * Obtain current latency information for the given neighbour.
3747  *
3748  * @param peer to get the latency for
3749  * @return observed latency of the address, FOREVER if the
3750  *         the connection is not up
3751  */
3752 struct GNUNET_TIME_Relative
3753 GST_neighbour_get_latency (const struct GNUNET_PeerIdentity *peer)
3754 {
3755   struct NeighbourMapEntry *n;
3756
3757   n = lookup_neighbour (peer);
3758   if (NULL == n)
3759     return GNUNET_TIME_UNIT_FOREVER_REL;
3760   switch (n->state)
3761   {
3762   case GNUNET_TRANSPORT_PS_CONNECTED:
3763   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_CONNECT_SENT:
3764   case GNUNET_TRANSPORT_PS_CONNECTED_SWITCHING_BLACKLIST:
3765   case GNUNET_TRANSPORT_PS_RECONNECT_SENT:
3766   case GNUNET_TRANSPORT_PS_RECONNECT_ATS:
3767   case GNUNET_TRANSPORT_PS_RECONNECT_BLACKLIST:
3768     return n->latency;
3769   case GNUNET_TRANSPORT_PS_NOT_CONNECTED:
3770   case GNUNET_TRANSPORT_PS_INIT_BLACKLIST:
3771   case GNUNET_TRANSPORT_PS_INIT_ATS:
3772   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST_INBOUND:
3773   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ATS:
3774   case GNUNET_TRANSPORT_PS_CONNECT_RECV_BLACKLIST:
3775   case GNUNET_TRANSPORT_PS_CONNECT_RECV_ACK:
3776   case GNUNET_TRANSPORT_PS_CONNECT_SENT:
3777   case GNUNET_TRANSPORT_PS_DISCONNECT:
3778   case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED:
3779     return GNUNET_TIME_UNIT_FOREVER_REL;
3780   default:
3781     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3782                 "Unhandled state `%s'\n",
3783                 GNUNET_TRANSPORT_ps2s (n->state));
3784     GNUNET_break (0);
3785     break;
3786   }
3787   return GNUNET_TIME_UNIT_FOREVER_REL;
3788 }
3789
3790
3791 /**
3792  * Obtain current address information for the given neighbour.
3793  *
3794  * @param peer
3795  * @return address currently used
3796  */
3797 struct GNUNET_HELLO_Address *
3798 GST_neighbour_get_current_address (const struct GNUNET_PeerIdentity *peer)
3799 {
3800   struct NeighbourMapEntry *n;
3801
3802   n = lookup_neighbour (peer);
3803   if (NULL == n)
3804     return NULL;
3805   return n->primary_address.address;
3806 }
3807
3808
3809 /**
3810  * Initialize the neighbours subsystem.
3811  *
3812  * @param cls closure for callbacks
3813  * @param connect_cb function to call if we connect to a peer
3814  * @param disconnect_cb function to call if we disconnect from a peer
3815  * @param peer_address_cb function to call if we change an active address
3816  *                   of a neighbour
3817  * @param max_fds maximum number of fds to use
3818  */
3819 void
3820 GST_neighbours_start (void *cls,
3821                       NotifyConnect connect_cb,
3822                       GNUNET_TRANSPORT_NotifyDisconnect disconnect_cb,
3823                       GNUNET_TRANSPORT_NeighbourChangeCallback peer_address_cb,
3824                       unsigned int max_fds)
3825 {
3826   callback_cls = cls;
3827   connect_notify_cb = connect_cb;
3828   disconnect_notify_cb = disconnect_cb;
3829   neighbour_change_cb = peer_address_cb;
3830   neighbours = GNUNET_CONTAINER_multipeermap_create (NEIGHBOUR_TABLE_SIZE, GNUNET_NO);
3831   registered_quota_notifications = GNUNET_CONTAINER_multipeermap_create (NEIGHBOUR_TABLE_SIZE, GNUNET_NO);
3832   util_transmission_tk = GNUNET_SCHEDULER_add_delayed (UTIL_TRANSMISSION_INTERVAL,
3833       utilization_transmission, NULL);
3834 }
3835
3836
3837 /**
3838  * Disconnect from the given neighbour.
3839  *
3840  * @param cls unused
3841  * @param key hash of neighbour's public key (not used)
3842  * @param value the 'struct NeighbourMapEntry' of the neighbour
3843  * @return #GNUNET_OK (continue to iterate)
3844  */
3845 static int
3846 disconnect_all_neighbours (void *cls,
3847                            const struct GNUNET_PeerIdentity *key,
3848                            void *value)
3849 {
3850   struct NeighbourMapEntry *n = value;
3851
3852   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3853               "Disconnecting peer `%4s', %s\n",
3854               GNUNET_i2s (&n->id), "SHUTDOWN_TASK");
3855   set_state (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED);
3856   free_neighbour (n, GNUNET_NO);
3857   return GNUNET_OK;
3858 }
3859
3860
3861 /**
3862  * Cleanup the neighbours subsystem.
3863  */
3864 void
3865 GST_neighbours_stop ()
3866 {
3867   struct BlacklistCheckSwitchContext *cur;
3868   struct BlacklistCheckSwitchContext *next;
3869
3870   if (NULL == neighbours)
3871     return;
3872   if (GNUNET_SCHEDULER_NO_TASK != util_transmission_tk)
3873   {
3874     GNUNET_SCHEDULER_cancel (util_transmission_tk);
3875     util_transmission_tk = GNUNET_SCHEDULER_NO_TASK;
3876   }
3877
3878   GNUNET_CONTAINER_multipeermap_iterate (neighbours,
3879                                          &disconnect_all_neighbours,
3880                                          NULL);
3881   GNUNET_CONTAINER_multipeermap_destroy (neighbours);
3882
3883   next = pending_bc_head;
3884   for (cur = next; NULL != cur; cur = next )
3885   {
3886     next = cur->next;
3887     GNUNET_CONTAINER_DLL_remove (pending_bc_head, pending_bc_tail, cur);
3888
3889     if (NULL != cur->blc)
3890     {
3891       GST_blacklist_test_cancel (cur->blc);
3892       cur->blc = NULL;
3893     }
3894     if (NULL != cur->address)
3895       GNUNET_HELLO_address_free (cur->address);
3896     GNUNET_free_non_null (cur->ats);
3897     GNUNET_free (cur);
3898   }
3899
3900   GNUNET_CONTAINER_multipeermap_iterate (registered_quota_notifications,
3901       &free_notification_cb, NULL);
3902   GNUNET_CONTAINER_multipeermap_destroy (registered_quota_notifications);
3903   registered_quota_notifications = NULL;
3904
3905   neighbours = NULL;
3906   callback_cls = NULL;
3907   connect_notify_cb = NULL;
3908   disconnect_notify_cb = NULL;
3909   neighbour_change_cb = NULL;
3910 }
3911
3912
3913 /* end of file gnunet-service-transport_neighbours.c */