summaryrefslogtreecommitdiff
path: root/src/mesh/gnunet-service-mesh_local.c
blob: fa54fafa638fb72a8e6acd5a1a45b535d506a557 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
/*
     This file is part of GNUnet.
     (C) 2013 Christian Grothoff (and other contributing authors)

     GNUnet is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published
     by the Free Software Foundation; either version 3, or (at your
     option) any later version.

     GNUnet is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/


#include "platform.h"
#include "gnunet_util_lib.h"

#include "gnunet_statistics_service.h"

#include "mesh.h"
#include "mesh_protocol.h" /* GNUNET_MESH_Data is shared */

#include "gnunet-service-mesh_local.h"
#include "gnunet-service-mesh_channel.h"

#define LOG(level, ...) GNUNET_log_from(level,"mesh-loc",__VA_ARGS__)

/******************************************************************************/
/********************************   STRUCTS  **********************************/
/******************************************************************************/

/**
 * Struct containing information about a client of the service
 *
 * TODO: add a list of 'waiting' ports
 */
struct MeshClient
{
    /**
     * Linked list next
     */
  struct MeshClient *next;

    /**
     * Linked list prev
     */
  struct MeshClient *prev;

    /**
     * Tunnels that belong to this client, indexed by local id
     */
  struct GNUNET_CONTAINER_MultiHashMap32 *own_channels;

    /**
     * Tunnels this client has accepted, indexed by incoming local id
     */
  struct GNUNET_CONTAINER_MultiHashMap32 *incoming_channels;

    /**
     * Channel ID for the next incoming channel.
     */
  MESH_ChannelNumber next_chid;

    /**
     * Handle to communicate with the client
     */
  struct GNUNET_SERVER_Client *handle;

    /**
     * Ports that this client has declared interest in.
     * Indexed by port, contains *Client.
     */
  struct GNUNET_CONTAINER_MultiHashMap32 *ports;

    /**
     * Whether the client is active or shutting down (don't send confirmations
     * to a client that is shutting down.
     */
  int shutting_down;

    /**
     * ID of the client, mainly for debug messages
     */
  unsigned int id;
};

/******************************************************************************/
/*******************************   GLOBALS  ***********************************/
/******************************************************************************/

/**
 * Global handle to the statistics service.
 */
extern struct GNUNET_STATISTICS_Handle *stats;

/**
 * Handle to server lib.
 */
static struct GNUNET_SERVER_Handle *server_handle;

/**
 * DLL with all the clients, head.
 */
static struct MeshClient *clients_head;

/**
 * DLL with all the clients, tail.
 */
static struct MeshClient *clients_tail;

/**
 * Next ID to assign to a client.
 */
unsigned int next_client_id;

/**
 * All ports clients of this peer have opened.
 */
static struct GNUNET_CONTAINER_MultiHashMap32 *ports;

/**
 * Notification context, to send messages to local clients.
 */
static struct GNUNET_SERVER_NotificationContext *nc;


/******************************************************************************/
/********************************   STATIC  ***********************************/
/******************************************************************************/

/**
 * Remove client's ports from the global hashmap on disconnect.
 *
 * @param cls Closure (unused).
 * @param key Port.
 * @param value Client structure.
 *
 * @return GNUNET_OK, keep iterating.
 */
static int
client_release_ports (void *cls,
                      uint32_t key,
                      void *value)
{
  int res;

  res = GNUNET_CONTAINER_multihashmap32_remove (ports, key, value);
  if (GNUNET_YES != res)
  {
    GNUNET_break (0);
    LOG (GNUNET_ERROR_TYPE_WARNING,
                "Port %u by client %p was not registered.\n",
                key, value);
  }
  return GNUNET_OK;
}



/******************************************************************************/
/********************************  HANDLES  ***********************************/
/******************************************************************************/


/**
 * Handler for client connection.
 *
 * @param cls Closure (unused).
 * @param client Client handler.
 */
static void
handle_client_connect (void *cls, struct GNUNET_SERVER_Client *client)
{
  struct MeshClient *c;

  LOG (GNUNET_ERROR_TYPE_DEBUG, "client connected: %p\n", client);
  if (NULL == client)
    return;
  c = GNUNET_new (struct MeshClient);
  c->handle = client;
  c->id = next_client_id++; /* overflow not important: just for debug */
  c->next_chid = GNUNET_MESH_LOCAL_CHANNEL_ID_SERV;
  GNUNET_SERVER_client_keep (client);
  GNUNET_SERVER_client_set_user_context (client, c);
  GNUNET_CONTAINER_DLL_insert (clients_head, clients_tail, c);
}


/**
 * Iterator for deleting each channel whose client endpoint disconnected.
 *
 * @param cls Closure (client that has disconnected).
 * @param key The local channel id (used to access the hashmap).
 * @param value The value stored at the key (channel to destroy).
 *
 * @return GNUNET_OK, keep iterating.
 */
static int
channel_destroy_iterator (void *cls,
                          uint32_t key,
                          void *value)
{
  struct MeshChannel *ch = value;
  struct MeshClient *c = cls;

  LOG (GNUNET_ERROR_TYPE_DEBUG,
              " Channel %s destroy, due to client %s shutdown.\n",
              GMCH_2s (ch), GML_2s (c));

  GMCH_handle_local_destroy (ch, c, key < GNUNET_MESH_LOCAL_CHANNEL_ID_SERV);
  return GNUNET_OK;
}

/**
 * Handler for client disconnection
 *
 * @param cls closure
 * @param client identification of the client; NULL
 *        for the last call when the server is destroyed
 */
static void
handle_client_disconnect (void *cls, struct GNUNET_SERVER_Client *client)
{
  struct MeshClient *c;

  LOG (GNUNET_ERROR_TYPE_DEBUG, "client disconnected: %p\n", client);
  if (client == NULL)
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG, "   (SERVER DOWN)\n");
    return;
  }

  c = GML_client_get (client);
  if (NULL != c)
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG, "matching client found (%u, %p)\n",
                c->id, c);
    GNUNET_SERVER_client_drop (c->handle);
    c->shutting_down = GNUNET_YES;
    if (NULL != c->own_channels)
    {
      GNUNET_CONTAINER_multihashmap32_iterate (c->own_channels,
                                               &channel_destroy_iterator, c);
      GNUNET_CONTAINER_multihashmap32_destroy (c->own_channels);
    }

    if (NULL != c->incoming_channels)
    {
      GNUNET_CONTAINER_multihashmap32_iterate (c->incoming_channels,
                                               &channel_destroy_iterator, c);
      GNUNET_CONTAINER_multihashmap32_destroy (c->incoming_channels);
    }

    if (NULL != c->ports)
    {
      GNUNET_CONTAINER_multihashmap32_iterate (c->ports,
                                               &client_release_ports, c);
      GNUNET_CONTAINER_multihashmap32_destroy (c->ports);
    }
    GNUNET_CONTAINER_DLL_remove (clients_head, clients_tail, c);
    GNUNET_STATISTICS_update (stats, "# clients", -1, GNUNET_NO);
    LOG (GNUNET_ERROR_TYPE_DEBUG, "  client free (%p)\n", c);
    GNUNET_free (c);
  }
  else
  {
    LOG (GNUNET_ERROR_TYPE_WARNING, " context NULL!\n");
  }
  LOG (GNUNET_ERROR_TYPE_DEBUG, "done!\n");
  return;
}


/**
 * Handler for new clients
 *
 * @param cls closure
 * @param client identification of the client
 * @param message the actual message, which includes messages the client wants
 */
static void
handle_new_client (void *cls, struct GNUNET_SERVER_Client *client,
                   const struct GNUNET_MessageHeader *message)
{
  struct GNUNET_MESH_ClientConnect *cc_msg;
  struct MeshClient *c;
  unsigned int size;
  uint32_t *p;
  unsigned int i;

  LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\nnew client connected %p\n", client);

  /* Check data sanity */
  size = ntohs (message->size) - sizeof (struct GNUNET_MESH_ClientConnect);
  cc_msg = (struct GNUNET_MESH_ClientConnect *) message;
  if (0 != (size % sizeof (uint32_t)))
  {
    GNUNET_break (0);
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }
  size /= sizeof (uint32_t);

  /* Initialize new client structure */
  c = GNUNET_SERVER_client_get_user_context (client, struct MeshClient);
  LOG (GNUNET_ERROR_TYPE_DEBUG, "  client id %u\n", c->id);
  LOG (GNUNET_ERROR_TYPE_DEBUG, "  client has %u ports\n", size);
  if (size > 0)
  {
    uint32_t u32;

    p = (uint32_t *) &cc_msg[1];
    c->ports = GNUNET_CONTAINER_multihashmap32_create (size);
    for (i = 0; i < size; i++)
    {
      u32 = ntohl (p[i]);
      LOG (GNUNET_ERROR_TYPE_DEBUG, "    port: %u\n", u32);

      /* store in client's hashmap */
      GNUNET_CONTAINER_multihashmap32_put (c->ports, u32, c,
                                           GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST);
      /* store in global hashmap */
      /* FIXME only allow one client to have the port open,
       *       have a backup hashmap with waiting clients */
      GNUNET_CONTAINER_multihashmap32_put (ports, u32, c,
                                           GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
    }
  }

  c->own_channels = GNUNET_CONTAINER_multihashmap32_create (32);
  c->incoming_channels = GNUNET_CONTAINER_multihashmap32_create (32);
  GNUNET_SERVER_notification_context_add (nc, client);
  GNUNET_STATISTICS_update (stats, "# clients", 1, GNUNET_NO);

  GNUNET_SERVER_receive_done (client, GNUNET_OK);
  LOG (GNUNET_ERROR_TYPE_DEBUG, "new client processed\n");
}


/**
 * Handler for requests of new tunnels
 *
 * @param cls Closure.
 * @param client Identification of the client.
 * @param message The actual message.
 */
static void
handle_channel_create (void *cls, struct GNUNET_SERVER_Client *client,
                       const struct GNUNET_MessageHeader *message)
{
  struct MeshClient *c;

  LOG (GNUNET_ERROR_TYPE_DEBUG, "\n");
  LOG (GNUNET_ERROR_TYPE_DEBUG, "new channel requested\n");

  /* Sanity check for client registration */
  if (NULL == (c = GML_client_get (client)))
  {
    GNUNET_break (0);
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }
  LOG (GNUNET_ERROR_TYPE_DEBUG, "  by client %u\n", c->id);

  /* Message size sanity check */
  if (sizeof (struct GNUNET_MESH_ChannelMessage) != ntohs (message->size))
  {
    GNUNET_break (0);
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }

  if (GNUNET_OK !=
      GMCH_handle_local_create (c,
                                (struct GNUNET_MESH_ChannelMessage *) message))
  {
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }

  GNUNET_SERVER_receive_done (client, GNUNET_OK);
  return;
}


/**
 * Handler for requests of deleting tunnels
 *
 * @param cls closure
 * @param client identification of the client
 * @param message the actual message
 */
static void
handle_channel_destroy (void *cls, struct GNUNET_SERVER_Client *client,
                        const struct GNUNET_MessageHeader *message)
{
  struct GNUNET_MESH_ChannelMessage *msg;
  struct MeshClient *c;
  struct MeshChannel *ch;
  MESH_ChannelNumber chid;

  LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\nGot a DESTROY CHANNEL from client!\n");

  /* Sanity check for client registration */
  if (NULL == (c = GML_client_get (client)))
  {
    GNUNET_break (0);
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }
  LOG (GNUNET_ERROR_TYPE_DEBUG, "  by client %u\n", c->id);

  /* Message sanity check */
  if (sizeof (struct GNUNET_MESH_ChannelMessage) != ntohs (message->size))
  {
    GNUNET_break (0);
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }

  msg = (struct GNUNET_MESH_ChannelMessage *) message;

  /* Retrieve tunnel */
  chid = ntohl (msg->channel_id);
  LOG (GNUNET_ERROR_TYPE_DEBUG, "  for channel %X\n", chid);
  ch = GML_channel_get (c, chid);
  if (NULL == ch)
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG, "  channel %X not found\n", chid);
    GNUNET_STATISTICS_update (stats,
                              "# client destroy messages on unknown channel",
                              1, GNUNET_NO);
    GNUNET_SERVER_receive_done (client, GNUNET_OK);
    return;
  }

  GMCH_handle_local_destroy (ch, c, chid < GNUNET_MESH_LOCAL_CHANNEL_ID_SERV);

  GNUNET_SERVER_receive_done (client, GNUNET_OK);
  return;
}


/**
 * Handler for client traffic
 *
 * @param cls closure
 * @param client identification of the client
 * @param message the actual message
 */
static void
handle_data (void *cls, struct GNUNET_SERVER_Client *client,
             const struct GNUNET_MessageHeader *message)
{
  struct GNUNET_MESH_LocalData *msg;
  struct MeshClient *c;
  struct MeshChannel *ch;
  MESH_ChannelNumber chid;
  size_t size;
  int fwd;

  LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\nGot data from a client!\n");

  /* Sanity check for client registration */
  if (NULL == (c = GML_client_get (client)))
  {
    GNUNET_break (0);
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }
  LOG (GNUNET_ERROR_TYPE_DEBUG, "  by client %u\n", c->id);

  msg = (struct GNUNET_MESH_LocalData *) message;

  /* Sanity check for message size */
  size = ntohs (message->size) - sizeof (struct GNUNET_MESH_LocalData);
  if (size < sizeof (struct GNUNET_MessageHeader))
  {
    GNUNET_break (0);
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }

  /* Channel exists? */
  chid = ntohl (msg->id);
  LOG (GNUNET_ERROR_TYPE_DEBUG, "  on channel %X\n", chid);
  fwd = chid < GNUNET_MESH_LOCAL_CHANNEL_ID_SERV;
  ch = GML_channel_get (c, chid);
  if (NULL == ch)
  {
    GNUNET_STATISTICS_update (stats,
                              "# client data messages on unknown channel",
                              1, GNUNET_NO);
    GNUNET_SERVER_receive_done (client, GNUNET_OK);
    return;
  }

  if (GNUNET_OK !=
      GMCH_handle_local_data (ch, c,
                              (struct GNUNET_MessageHeader *)&msg[1], fwd))
  {
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }

  LOG (GNUNET_ERROR_TYPE_DEBUG, "receive done OK\n");
  GNUNET_SERVER_receive_done (client, GNUNET_OK);

  return;
}


/**
 * Handler for client's ACKs for payload traffic.
 *
 * @param cls Closure (unused).
 * @param client Identification of the client.
 * @param message The actual message.
 */
static void
handle_ack (void *cls, struct GNUNET_SERVER_Client *client,
            const struct GNUNET_MessageHeader *message)
{
  struct GNUNET_MESH_LocalAck *msg;
  struct MeshChannel *ch;
  struct MeshClient *c;
  MESH_ChannelNumber chid;
  int fwd;

  LOG (GNUNET_ERROR_TYPE_DEBUG, "\n");
  LOG (GNUNET_ERROR_TYPE_DEBUG, "Got a local ACK\n");

  /* Sanity check for client registration */
  if (NULL == (c = GML_client_get (client)))
  {
    GNUNET_break (0);
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }
  LOG (GNUNET_ERROR_TYPE_DEBUG, "  by client %u\n", c->id);

  msg = (struct GNUNET_MESH_LocalAck *) message;

  /* Channel exists? */
  chid = ntohl (msg->channel_id);
  LOG (GNUNET_ERROR_TYPE_DEBUG, "  on channel %X\n", chid);
  ch = GML_channel_get (c, chid);
  LOG (GNUNET_ERROR_TYPE_DEBUG, "   -- ch %p\n", ch);
  if (NULL == ch)
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %X unknown.\n", chid);
    LOG (GNUNET_ERROR_TYPE_DEBUG, "  for client %u.\n", c->id);
    GNUNET_STATISTICS_update (stats,
                              "# client ack messages on unknown channel",
                              1, GNUNET_NO);
    GNUNET_SERVER_receive_done (client, GNUNET_OK);
    return;
  }

  /* If client is root, the ACK is going FWD, therefore this is "BCK ACK". */
  /* If client is dest, the ACK is going BCK, therefore this is "FWD ACK" */
  fwd = chid >= GNUNET_MESH_LOCAL_CHANNEL_ID_SERV;

  GMCH_handle_local_ack (ch, fwd);
  GNUNET_SERVER_receive_done (client, GNUNET_OK);

  return;
}


/*
 * Iterator over all tunnels to send a monitoring client info about each tunnel.
 *
 * @param cls Closure (client handle).
 * @param key Key (hashed tunnel ID, unused).
 * @param value Tunnel info.
 *
 * @return #GNUNET_YES, to keep iterating.
 */
// static int
// monitor_all_tunnels_iterator (void *cls,
//                               const struct GNUNET_HashCode * key,
//                               void *value)
// {
//   struct GNUNET_SERVER_Client *client = cls;
//   struct MeshChannel *ch = value;
//   struct GNUNET_MESH_LocalMonitor *msg;
//
//   msg = GNUNET_new (struct GNUNET_MESH_LocalMonitor);
//   msg->channel_id = htonl (ch->gid);
//   msg->header.size = htons (sizeof (struct GNUNET_MESH_LocalMonitor));
//   msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_LOCAL_INFO_TUNNELS);
//
//   LOG (GNUNET_ERROR_TYPE_INFO,
//               "*  sending info about tunnel %s\n",
//               GNUNET_i2s (&msg->owner));
//
//   GNUNET_SERVER_notification_context_unicast (nc, client,
//                                               &msg->header, GNUNET_NO);
//   return GNUNET_YES;
// }


/**
 * Handler for client's MONITOR request.
 *
 * @param cls Closure (unused).
 * @param client Identification of the client.
 * @param message The actual message.
 */
static void
handle_get_tunnels (void *cls, struct GNUNET_SERVER_Client *client,
                    const struct GNUNET_MessageHeader *message)
{
  struct MeshClient *c;

  /* Sanity check for client registration */
  if (NULL == (c = GML_client_get (client)))
  {
    GNUNET_break (0);
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }

  LOG (GNUNET_ERROR_TYPE_INFO,
              "Received get tunnels request from client %u\n",
              c->id);
//   GNUNET_CONTAINER_multihashmap_iterate (tunnels,
//                                          monitor_all_tunnels_iterator,
//                                          client);
  LOG (GNUNET_ERROR_TYPE_INFO,
              "Get tunnels request from client %u completed\n",
              c->id);
  GNUNET_SERVER_receive_done (client, GNUNET_OK);
}


/**
 * Handler for client's MONITOR_TUNNEL request.
 *
 * @param cls Closure (unused).
 * @param client Identification of the client.
 * @param message The actual message.
 */
void
handle_show_tunnel (void *cls, struct GNUNET_SERVER_Client *client,
                    const struct GNUNET_MessageHeader *message)
{
  const struct GNUNET_MESH_LocalMonitor *msg;
  struct GNUNET_MESH_LocalMonitor *resp;
  struct MeshClient *c;
  struct MeshChannel *ch;

  /* Sanity check for client registration */
  if (NULL == (c = GML_client_get (client)))
  {
    GNUNET_break (0);
    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
    return;
  }

  msg = (struct GNUNET_MESH_LocalMonitor *) message;
  LOG (GNUNET_ERROR_TYPE_INFO,
              "Received tunnel info request from client %u for tunnel %s[%X]\n",
              c->id,
              &msg->owner,
              ntohl (msg->channel_id));
//   ch = channel_get (&msg->owner, ntohl (msg->channel_id));
  ch = NULL; // FIXME
  if (NULL == ch)
  {
    /* We don't know the tunnel */
    struct GNUNET_MESH_LocalMonitor warn;

    warn = *msg;
    GNUNET_SERVER_notification_context_unicast (nc, client,
                                                &warn.header,
                                                GNUNET_NO);
    GNUNET_SERVER_receive_done (client, GNUNET_OK);
    return;
  }

  /* Initialize context */
  resp = GNUNET_new (struct GNUNET_MESH_LocalMonitor);
  *resp = *msg;
  resp->header.size = htons (sizeof (struct GNUNET_MESH_LocalMonitor));
  GNUNET_SERVER_notification_context_unicast (nc, c->handle,
                                              &resp->header, GNUNET_NO);
  GNUNET_free (resp);

  LOG (GNUNET_ERROR_TYPE_INFO,
              "Monitor tunnel request from client %u completed\n",
              c->id);
  GNUNET_SERVER_receive_done (client, GNUNET_OK);
}


/**
 * Functions to handle messages from clients
 */
static struct GNUNET_SERVER_MessageHandler client_handlers[] = {
  {&handle_new_client, NULL, GNUNET_MESSAGE_TYPE_MESH_LOCAL_CONNECT, 0},
  {&handle_channel_create, NULL, GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE,
   sizeof (struct GNUNET_MESH_ChannelMessage)},
  {&handle_channel_destroy, NULL, GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY,
   sizeof (struct GNUNET_MESH_ChannelMessage)},
  {&handle_data, NULL, GNUNET_MESSAGE_TYPE_MESH_LOCAL_DATA, 0},
  {&handle_ack, NULL, GNUNET_MESSAGE_TYPE_MESH_LOCAL_ACK,
   sizeof (struct GNUNET_MESH_LocalAck)},
  {&handle_get_tunnels, NULL, GNUNET_MESSAGE_TYPE_MESH_LOCAL_INFO_TUNNELS,
   sizeof (struct GNUNET_MessageHeader)},
  {&handle_show_tunnel, NULL, GNUNET_MESSAGE_TYPE_MESH_LOCAL_INFO_TUNNEL,
   sizeof (struct GNUNET_MESH_LocalMonitor)},
  {NULL, NULL, 0, 0}
};



/******************************************************************************/
/********************************    API    ***********************************/
/******************************************************************************/

/**
 * Initialize server subsystem.
 *
 * @param handle Server handle.
 */
void
GML_init (struct GNUNET_SERVER_Handle *handle)
{
  LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
  server_handle = handle;
  GNUNET_SERVER_suspend (server_handle);
  ports = GNUNET_CONTAINER_multihashmap32_create (32);
}


/**
 * Install server (service) handlers and start listening to clients.
 */
void
GML_start (void)
{
  GNUNET_SERVER_add_handlers (server_handle, client_handlers);
  GNUNET_SERVER_connect_notify (server_handle,  &handle_client_connect, NULL);
  GNUNET_SERVER_disconnect_notify (server_handle, &handle_client_disconnect,
                                   NULL);
  nc = GNUNET_SERVER_notification_context_create (server_handle, 1);

  clients_head = NULL;
  clients_tail = NULL;
  next_client_id = 0;
  GNUNET_SERVER_resume (server_handle);
}


/**
 * Shutdown server.
 */
void
GML_shutdown (void)
{
  if (nc != NULL)
  {
    GNUNET_SERVER_notification_context_destroy (nc);
    nc = NULL;
  }
}


/**
 * Get a channel from a client.
 *
 * @param c Client to check.
 * @param chid Channel ID, must be local (> 0x800...).
 *
 * @return non-NULL if channel exists in the clients lists
 */
struct MeshChannel *
GML_channel_get (struct MeshClient *c, MESH_ChannelNumber chid)
{
  struct GNUNET_CONTAINER_MultiHashMap32 *map;

  if (0 == (chid & GNUNET_MESH_LOCAL_CHANNEL_ID_CLI))
  {
    GNUNET_break_op (0);
    LOG (GNUNET_ERROR_TYPE_DEBUG, "CHID %X not a local chid\n", chid);
    return NULL;
  }

  if (chid >= GNUNET_MESH_LOCAL_CHANNEL_ID_SERV)
    map = c->incoming_channels;
  else if (chid >= GNUNET_MESH_LOCAL_CHANNEL_ID_CLI)
    map = c->own_channels;
  else
  {
    GNUNET_break (0);
    map = NULL;
  }
  if (NULL == map)
  {
    GNUNET_break (0);
    LOG (GNUNET_ERROR_TYPE_DEBUG,
         "Client %s does no t have a valid map for CHID %X\n",
         GML_2s (c), chid);
    return NULL;
  }
  return GNUNET_CONTAINER_multihashmap32_get (map, chid);
}


/**
 * Add a channel to a client
 *
 * @param client Client.
 * @param chid Channel ID.
 * @param ch Channel.
 */
void
GML_channel_add (struct MeshClient *client,
                 uint32_t chid,
                 struct MeshChannel *ch)
{
  if (chid >= GNUNET_MESH_LOCAL_CHANNEL_ID_SERV)
    GNUNET_CONTAINER_multihashmap32_put (client->incoming_channels, chid, ch,
                                         GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
  else if (chid >= GNUNET_MESH_LOCAL_CHANNEL_ID_CLI)
    GNUNET_CONTAINER_multihashmap32_put (client->own_channels, chid, ch,
                                         GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
  else
    GNUNET_break (0);
}


/**
 * Remove a channel from a client.
 *
 * @param client Client.
 * @param chid Channel ID.
 * @param ch Channel.
 */
void
GML_channel_remove (struct MeshClient *client,
                    uint32_t chid,
                    struct MeshChannel *ch)
{
  if (GNUNET_MESH_LOCAL_CHANNEL_ID_SERV <= chid)
    GNUNET_break (GNUNET_YES ==
                  GNUNET_CONTAINER_multihashmap32_remove (client->incoming_channels,
                                                          chid, ch));
  else if (GNUNET_MESH_LOCAL_CHANNEL_ID_CLI <= chid)
    GNUNET_break (GNUNET_YES ==
                  GNUNET_CONTAINER_multihashmap32_remove (client->own_channels,
                                                          chid, ch));
  else
    GNUNET_break (0);
}


/**
 * Get the tunnel's next free local channel ID.
 *
 * @param c Client.
 *
 * @return LID of a channel free to use.
 */
MESH_ChannelNumber
GML_get_next_chid (struct MeshClient *c)
{
  MESH_ChannelNumber chid;

  while (NULL != GML_channel_get (c, c->next_chid))
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %u exists...\n", c->next_chid);
    c->next_chid = (c->next_chid + 1) | GNUNET_MESH_LOCAL_CHANNEL_ID_SERV;
  }
  chid = c->next_chid;
  c->next_chid = (c->next_chid + 1) | GNUNET_MESH_LOCAL_CHANNEL_ID_SERV;

  return chid;
}


/**
 * Check if client has registered with the service and has not disconnected
 *
 * @param client the client to check
 *
 * @return non-NULL if client exists in the global DLL
 */
struct MeshClient *
GML_client_get (struct GNUNET_SERVER_Client *client)
{
  return GNUNET_SERVER_client_get_user_context (client, struct MeshClient);
}

/**
 * Find a client that has opened a port
 *
 * @param port Port to check.
 *
 * @return non-NULL if a client has the port.
 */
struct MeshClient *
GML_client_get_by_port (uint32_t port)
{
  return GNUNET_CONTAINER_multihashmap32_get (ports, port);
}


/**
 * Deletes a channel from a client (either owner or destination).
 *
 * @param c Client whose tunnel to delete.
 * @param ch Channel which should be deleted.
 * @param id Channel ID.
 */
void
GML_client_delete_channel (struct MeshClient *c,
                           struct MeshChannel *ch,
                           MESH_ChannelNumber id)
{
  int res;

  if (GNUNET_MESH_LOCAL_CHANNEL_ID_SERV <= id)
  {
    res = GNUNET_CONTAINER_multihashmap32_remove (c->incoming_channels,
                                                  id, ch);
    if (GNUNET_YES != res)
      LOG (GNUNET_ERROR_TYPE_DEBUG, "client_delete_channel dest KO\n");
  }
  else if (GNUNET_MESH_LOCAL_CHANNEL_ID_CLI <= id)
  {
    res = GNUNET_CONTAINER_multihashmap32_remove (c->own_channels,
                                                  id, ch);
    if (GNUNET_YES != res)
      LOG (GNUNET_ERROR_TYPE_DEBUG, "client_delete_tunnel root KO\n");
  }
  else
  {
    GNUNET_break (0);
  }
}

/**
 * Build a local ACK message and send it to a local client, if needed.
 *
 * If the client was already allowed to send data, do nothing.
 *
 * @param c Client to whom send the ACK.
 * @param id Channel ID to use
 */
void
GML_send_ack (struct MeshClient *c, MESH_ChannelNumber id)
{
  struct GNUNET_MESH_LocalAck msg;

  LOG (GNUNET_ERROR_TYPE_DEBUG,
              "send local %s ack on %X towards %p\n",
              id < GNUNET_MESH_LOCAL_CHANNEL_ID_SERV ? "FWD" : "BCK", id, c);

  msg.header.size = htons (sizeof (msg));
  msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_LOCAL_ACK);
  msg.channel_id = htonl (id);
  GNUNET_SERVER_notification_context_unicast (nc,
                                              c->handle,
                                              &msg.header,
                                              GNUNET_NO);

}


/**
 * Build a local channel NACK message and send it to a local client.
 *
 * @param c Client to whom send the NACK.
 * @param id Channel ID to use
 */
void
GML_send_nack (struct MeshClient *c, MESH_ChannelNumber id)
{
  struct GNUNET_MESH_LocalAck msg;

  LOG (GNUNET_ERROR_TYPE_DEBUG,
              "send local nack on %X towards %p\n",
              id, c);

  msg.header.size = htons (sizeof (msg));
  msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_LOCAL_NACK);
  msg.channel_id = htonl (id);
  GNUNET_SERVER_notification_context_unicast (nc,
                                              c->handle,
                                              &msg.header,
                                              GNUNET_NO);

}


/**
 * Notify the client that a new incoming channel was created.
 *
 * @param c Client to notify.
 * @param id Channel ID.
 * @param port Channel's destination port.
 * @param opt Options (bit array).
 * @param peer Origin peer.
 */
void
GML_send_channel_create (struct MeshClient *c,
                         uint32_t id, uint32_t port, uint32_t opt,
                         const struct GNUNET_PeerIdentity *peer)
{
  struct GNUNET_MESH_ChannelMessage msg;

  msg.header.size = htons (sizeof (msg));
  msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE);
  msg.channel_id = htonl (id);
  msg.port = htonl (port);
  msg.opt = htonl (opt);
  msg.peer = *peer;
  GNUNET_SERVER_notification_context_unicast (nc, c->handle,
                                              &msg.header, GNUNET_NO);
}


/**
 * Notify a client that a channel is no longer valid.
 *
 * @param c Client.
 * @param id ID of the channel that is destroyed.
 */
void
GML_send_channel_destroy (struct MeshClient *c, uint32_t id)
{
  struct GNUNET_MESH_ChannelMessage msg;

  if (NULL == c)
  {
    GNUNET_break (0);
    return;
  }
  if (GNUNET_YES == c->shutting_down)
    return;
  msg.header.size = htons (sizeof (msg));
  msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY);
  msg.channel_id = htonl (id);
  msg.port = htonl (0);
  memset (&msg.peer, 0, sizeof (msg.peer));
  msg.opt = htonl (0);
  GNUNET_SERVER_notification_context_unicast (nc, c->handle,
                                              &msg.header, GNUNET_NO);
}


/**
 * Modify the mesh message ID from global to local and send to client.
 *
 * @param c Client to send to.
 * @param msg Message to modify and send.
 * @param id Channel ID to use (c can be both owner and client).
 */
void
GML_send_data (struct MeshClient *c,
               const struct GNUNET_MESH_Data *msg,
               MESH_ChannelNumber id)
{
  struct GNUNET_MESH_LocalData *copy;
  uint16_t size = ntohs (msg->header.size) - sizeof (struct GNUNET_MESH_Data);
  char cbuf[size + sizeof (struct GNUNET_MESH_LocalData)];

  if (size < sizeof (struct GNUNET_MessageHeader))
  {
    GNUNET_break_op (0);
    return;
  }
  if (NULL == c)
  {
    GNUNET_break (0);
    return;
  }
  copy = (struct GNUNET_MESH_LocalData *) cbuf;
  memcpy (&copy[1], &msg[1], size);
  copy->header.size = htons (sizeof (struct GNUNET_MESH_LocalData) + size);
  copy->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_LOCAL_DATA);
  copy->id = htonl (id);
  GNUNET_SERVER_notification_context_unicast (nc, c->handle,
                                              &copy->header, GNUNET_NO);
}


/**
 * Get the static string to represent a client.
 *
 * @param c Client.
 *
 * @return Static string for the client.
 */
const char *
GML_2s (const struct MeshClient *c)
{
  static char buf[32];

  sprintf (buf, "%u", c->id);
  return buf;
}