GNUnet  0.10.x
gnunet-service-cadet_tunnels.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2013, 2017, 2018 GNUnet e.V.
4 
5  GNUnet is free software: you can redistribute it and/or modify it
6  under the terms of the GNU Affero General Public License as published
7  by the Free Software Foundation, either version 3 of the License,
8  or (at your 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  Affero General Public License for more details.
14 
15  You should have received a copy of the GNU Affero General Public License
16  along with this program. If not, see <http://www.gnu.org/licenses/>.
17 
18  SPDX-License-Identifier: AGPL3.0-or-later
19  */
33 #include "platform.h"
34 #include "gnunet_util_lib.h"
36 #include "gnunet_signatures.h"
37 #include "cadet_protocol.h"
43 
44 
45 #define LOG(level, ...) GNUNET_log_from(level, "cadet-tun", __VA_ARGS__)
46 
52 #define MAX_UNVERIFIED_ATTEMPTS 16
53 
57 #define IDLE_DESTROY_DELAY GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 90)
58 
63 #define INITIAL_KX_RETRY_DELAY GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MILLISECONDS, 250)
64 
68 #define MAX_SKIPPED_KEYS 64
69 
74 #define MAX_KEY_GAP 256
75 
76 
85 
90 
95 
100 
105 
109  unsigned int Kn;
110 };
111 
112 
123 
128 
133 
138 
143 
150 
157 
163 
171 
176 
181 
186 
191  struct GNUNET_CRYPTO_EcdhePublicKey last_ephemeral;
192 
197  struct GNUNET_TIME_Absolute ratchet_expiration;
198 
202  unsigned int skipped;
203 
207  uint32_t Ns;
208 
212  uint32_t Nr;
213 
217  uint32_t PNs;
218 
223 
235 
248  unsigned int ratchet_counter;
249 };
250 
251 
260 
265 
269  struct CadetTunnel *t;
270 
275 
279  void *cont_cls;
280 
285 
291 };
292 
293 
297 struct CadetTunnel {
302 
307  struct GNUNET_CRYPTO_EcdhePublicKey peers_ephemeral_key;
308 
313 
318 
323 
332 
337 
342 
347 
352 
357 
362 
367 
372 
377 
382 
388 
393 
398 
403 
410 
414  struct GNUNET_TIME_Relative kx_retry_delay;
415 
419  struct GNUNET_TIME_Absolute next_kx_attempt;
420 
424  unsigned int num_ready_connections;
425 
429  unsigned int num_busy_connections;
430 
436  unsigned int unverified_attempts;
437 
441  unsigned int tq_len;
442 
446  enum CadetTunnelEState estate;
447 
452 };
453 
454 
461 static int
463 {
464  if (0 > GNUNET_memcmp(&my_full_id,
465  other))
466  return GNUNET_YES;
467  else if (0 < GNUNET_memcmp(&my_full_id,
468  other))
469  return GNUNET_NO;
470  else
471  {
472  GNUNET_break_op(0);
473  return GNUNET_SYSERR;
474  }
475 }
476 
477 
484 static void
486 {
487  struct CadetTunnel *t = ct->t;
488 
492  ct);
495  ct->is_ready = GNUNET_NO;
498  ct);
500 }
501 
502 
510 const char *
511 GCT_2s(const struct CadetTunnel *t)
512 {
513  static char buf[64];
514 
515  if (NULL == t)
516  return "Tunnel(NULL)";
517  GNUNET_snprintf(buf,
518  sizeof(buf),
519  "Tunnel %s",
521  return buf;
522 }
523 
524 
532 static const char *
534 {
535  static char buf[32];
536 
537  switch (es)
538  {
540  return "CADET_TUNNEL_KEY_UNINITIALIZED";
541 
543  return "CADET_TUNNEL_KEY_AX_RECV";
544 
546  return "CADET_TUNNEL_KEY_AX_SENT";
547 
549  return "CADET_TUNNEL_KEY_AX_SENT_AND_RECV";
550 
552  return "CADET_TUNNEL_KEY_AX_AUTH_SENT";
553 
554  case CADET_TUNNEL_KEY_OK:
555  return "CADET_TUNNEL_KEY_OK";
556 
557  default:
558  GNUNET_snprintf(buf,
559  sizeof(buf),
560  "%u (UNKNOWN STATE)",
561  es);
562  return buf;
563  }
564 }
565 
566 
573 struct CadetPeer *
575 {
576  return t->destination;
577 }
578 
579 
587 unsigned int
589 {
591 }
592 
593 
601 struct CadetChannel *
604 {
606  ntohl(ctn.cn));
607 }
608 
609 
617 unsigned int
619 {
621 }
622 
623 
631 static struct CadetTConnection *
633 {
634  struct CadetTConnection *hd = t->connection_ready_head;
635 
636  GNUNET_assert((NULL == hd) ||
637  (GNUNET_YES == hd->is_ready));
638  return hd;
639 }
640 
641 
651 {
652  return t->estate;
653 }
654 
655 
664 static void
665 trigger_transmissions(void *cls);
666 
667 
668 /* ************************************** start core crypto ***************************** */
669 
670 
676 static void
678 {
680  "Creating new ephemeral ratchet key (DHRs)\n");
683 }
684 
685 
695 static void
696 t_hmac(const void *plaintext,
697  size_t size,
698  uint32_t iv,
700  struct GNUNET_ShortHashCode *hmac)
701 {
702  static const char ctx[] = "cadet authentication key";
703  struct GNUNET_CRYPTO_AuthKey auth_key;
704  struct GNUNET_HashCode hash;
705 
707  key,
708  &iv, sizeof(iv),
709  key, sizeof(*key),
710  ctx, sizeof(ctx),
711  NULL);
712  /* Two step: GNUNET_ShortHash is only 256 bits,
713  GNUNET_HashCode is 512, so we truncate. */
714  GNUNET_CRYPTO_hmac(&auth_key,
715  plaintext,
716  size,
717  &hash);
718  GNUNET_memcpy(hmac,
719  &hash,
720  sizeof(*hmac));
721 }
722 
723 
732 static void
734  struct GNUNET_HashCode *hash,
735  const void *source,
736  unsigned int len)
737 {
738  static const char ctx[] = "axolotl HMAC-HASH";
739  struct GNUNET_CRYPTO_AuthKey auth_key;
740 
742  key,
743  ctx, sizeof(ctx),
744  NULL);
745  GNUNET_CRYPTO_hmac(&auth_key,
746  source,
747  len,
748  hash);
749 }
750 
751 
760 static void
763  const void *source,
764  unsigned int len)
765 {
766  static const char ctx[] = "axolotl derive key";
767  struct GNUNET_HashCode h;
768 
769  t_ax_hmac_hash(key,
770  &h,
771  source,
772  len);
773  GNUNET_CRYPTO_kdf(out, sizeof(*out),
774  ctx, sizeof(ctx),
775  &h, sizeof(h),
776  NULL);
777 }
778 
779 
788 static void
790  void *dst,
791  const void *src,
792  size_t size)
793 {
796  size_t out_size;
797 
798  ax->ratchet_counter++;
799  if ((GNUNET_YES == ax->ratchet_allowed) &&
800  ((ratchet_messages <= ax->ratchet_counter) ||
802  {
803  ax->ratchet_flag = GNUNET_YES;
804  }
805  if (GNUNET_YES == ax->ratchet_flag)
806  {
807  /* Advance ratchet */
808  struct GNUNET_CRYPTO_SymmetricSessionKey keys[3];
809  struct GNUNET_HashCode dh;
810  struct GNUNET_HashCode hmac;
811  static const char ctx[] = "axolotl ratchet";
812 
813  new_ephemeral(ax);
814  ax->HKs = ax->NHKs;
815 
816  /* RK, NHKs, CKs = KDF( HMAC-HASH(RK, DH(DHRs, DHRr)) ) */
818  &ax->DHRr,
819  &dh);
820  t_ax_hmac_hash(&ax->RK,
821  &hmac,
822  &dh,
823  sizeof(dh));
824  GNUNET_CRYPTO_kdf(keys, sizeof(keys),
825  ctx, sizeof(ctx),
826  &hmac, sizeof(hmac),
827  NULL);
828  ax->RK = keys[0];
829  ax->NHKs = keys[1];
830  ax->CKs = keys[2];
831 
832  ax->PNs = ax->Ns;
833  ax->Ns = 0;
834  ax->ratchet_flag = GNUNET_NO;
836  ax->ratchet_counter = 0;
839  ratchet_time);
840  }
841 
842  t_hmac_derive_key(&ax->CKs,
843  &MK,
844  "0",
845  1);
847  &MK,
848  NULL, 0,
849  NULL);
850 
851  out_size = GNUNET_CRYPTO_symmetric_encrypt(src,
852  size,
853  &MK,
854  &iv,
855  dst);
856  GNUNET_assert(size == out_size);
857  t_hmac_derive_key(&ax->CKs,
858  &ax->CKs,
859  "1",
860  1);
861 }
862 
863 
872 static void
874  void *dst,
875  const void *src,
876  size_t size)
877 {
880  size_t out_size;
881 
882  t_hmac_derive_key(&ax->CKr,
883  &MK,
884  "0",
885  1);
887  &MK,
888  NULL, 0,
889  NULL);
890  GNUNET_assert(size >= sizeof(struct GNUNET_MessageHeader));
891  out_size = GNUNET_CRYPTO_symmetric_decrypt(src,
892  size,
893  &MK,
894  &iv,
895  dst);
896  GNUNET_assert(out_size == size);
897  t_hmac_derive_key(&ax->CKr,
898  &ax->CKr,
899  "1",
900  1);
901 }
902 
903 
910 static void
913 {
915  size_t out_size;
916 
918  &ax->HKs,
919  NULL, 0,
920  NULL);
922  sizeof(struct GNUNET_CADET_AxHeader),
923  &ax->HKs,
924  &iv,
925  &msg->ax_header);
926  GNUNET_assert(sizeof(struct GNUNET_CADET_AxHeader) == out_size);
927 }
928 
929 
937 static void
939  const struct GNUNET_CADET_TunnelEncryptedMessage *src,
941 {
943  size_t out_size;
944 
946  &ax->HKr,
947  NULL, 0,
948  NULL);
950  sizeof(struct GNUNET_CADET_AxHeader),
951  &ax->HKr,
952  &iv,
953  &dst->ax_header.Ns);
954  GNUNET_assert(sizeof(struct GNUNET_CADET_AxHeader) == out_size);
955 }
956 
957 
964 static void
966  struct CadetTunnelSkippedKey *key)
967 {
969  ax->skipped_tail,
970  key);
971  GNUNET_free(key);
972  ax->skipped--;
973 }
974 
975 
986 static ssize_t
988  void *dst,
989  const struct GNUNET_CADET_TunnelEncryptedMessage *src,
990  size_t size)
991 {
992  struct CadetTunnelSkippedKey *key;
993  struct GNUNET_ShortHashCode *hmac;
995  struct GNUNET_CADET_TunnelEncryptedMessage plaintext_header;
996  struct GNUNET_CRYPTO_SymmetricSessionKey *valid_HK;
997  size_t esize;
998  size_t res;
999  size_t len;
1000  unsigned int N;
1001 
1003  "Trying skipped keys\n");
1004  hmac = &plaintext_header.hmac;
1005  esize = size - sizeof(struct GNUNET_CADET_TunnelEncryptedMessage);
1006 
1007  /* Find a correct Header Key */
1008  valid_HK = NULL;
1009  for (key = ax->skipped_head; NULL != key; key = key->next)
1010  {
1011  t_hmac(&src->ax_header,
1012  sizeof(struct GNUNET_CADET_AxHeader) + esize,
1013  0,
1014  &key->HK,
1015  hmac);
1016  if (0 == GNUNET_memcmp(hmac,
1017  &src->hmac))
1018  {
1019  valid_HK = &key->HK;
1020  break;
1021  }
1022  }
1023  if (NULL == key)
1024  return -1;
1025 
1026  /* Should've been checked in -cadet_connection.c handle_cadet_encrypted. */
1027  GNUNET_assert(size > sizeof(struct GNUNET_CADET_TunnelEncryptedMessage));
1028  len = size - sizeof(struct GNUNET_CADET_TunnelEncryptedMessage);
1029  GNUNET_assert(len >= sizeof(struct GNUNET_MessageHeader));
1030 
1031  /* Decrypt header */
1033  &key->HK,
1034  NULL, 0,
1035  NULL);
1037  sizeof(struct GNUNET_CADET_AxHeader),
1038  &key->HK,
1039  &iv,
1040  &plaintext_header.ax_header.Ns);
1041  GNUNET_assert(sizeof(struct GNUNET_CADET_AxHeader) == res);
1042 
1043  /* Find the correct message key */
1044  N = ntohl(plaintext_header.ax_header.Ns);
1045  while ((NULL != key) &&
1046  (N != key->Kn))
1047  key = key->next;
1048  if ((NULL == key) ||
1049  (0 != GNUNET_memcmp(&key->HK,
1050  valid_HK)))
1051  return -1;
1052 
1053  /* Decrypt payload */
1055  &key->MK,
1056  NULL,
1057  0,
1058  NULL);
1059  res = GNUNET_CRYPTO_symmetric_decrypt(&src[1],
1060  len,
1061  &key->MK,
1062  &iv,
1063  dst);
1064  delete_skipped_key(ax,
1065  key);
1066  return res;
1067 }
1068 
1069 
1076 static void
1078  const struct GNUNET_CRYPTO_SymmetricSessionKey *HKr)
1079 {
1080  struct CadetTunnelSkippedKey *key;
1081 
1082  key = GNUNET_new(struct CadetTunnelSkippedKey);
1084  key->Kn = ax->Nr;
1085  key->HK = ax->HKr;
1086  t_hmac_derive_key(&ax->CKr,
1087  &key->MK,
1088  "0",
1089  1);
1090  t_hmac_derive_key(&ax->CKr,
1091  &ax->CKr,
1092  "1",
1093  1);
1095  ax->skipped_tail,
1096  key);
1097  ax->skipped++;
1098  ax->Nr++;
1099 }
1100 
1101 
1112 static int
1114  const struct GNUNET_CRYPTO_SymmetricSessionKey *HKr,
1115  uint32_t Np)
1116 {
1117  int gap;
1118 
1119  gap = Np - ax->Nr;
1121  "Storing skipped keys [%u, %u)\n",
1122  ax->Nr,
1123  Np);
1124  if (MAX_KEY_GAP < gap)
1125  {
1126  /* Avoid DoS (forcing peer to do more than #MAX_KEY_GAP HMAC operations) */
1127  /* TODO: start new key exchange on return */
1128  GNUNET_break_op(0);
1130  "Got message %u, expected %u+\n",
1131  Np,
1132  ax->Nr);
1133  return GNUNET_SYSERR;
1134  }
1135  if (0 > gap)
1136  {
1137  /* Delayed message: don't store keys, flag to try old keys. */
1138  return GNUNET_SYSERR;
1139  }
1140 
1141  while (ax->Nr < Np)
1142  store_skipped_key(ax,
1143  HKr);
1144 
1145  while (ax->skipped > MAX_SKIPPED_KEYS)
1146  delete_skipped_key(ax,
1147  ax->skipped_tail);
1148  return GNUNET_OK;
1149 }
1150 
1151 
1162 static ssize_t
1164  void *dst,
1165  const struct GNUNET_CADET_TunnelEncryptedMessage *src,
1166  size_t size)
1167 {
1168  struct GNUNET_ShortHashCode msg_hmac;
1169  struct GNUNET_HashCode hmac;
1170  struct GNUNET_CADET_TunnelEncryptedMessage plaintext_header;
1171  uint32_t Np;
1172  uint32_t PNp;
1173  size_t esize; /* Size of encryped payload */
1174 
1175  esize = size - sizeof(struct GNUNET_CADET_TunnelEncryptedMessage);
1176 
1177  /* Try current HK */
1178  t_hmac(&src->ax_header,
1179  sizeof(struct GNUNET_CADET_AxHeader) + esize,
1180  0, &ax->HKr,
1181  &msg_hmac);
1182  if (0 != GNUNET_memcmp(&msg_hmac,
1183  &src->hmac))
1184  {
1185  static const char ctx[] = "axolotl ratchet";
1186  struct GNUNET_CRYPTO_SymmetricSessionKey keys[3]; /* RKp, NHKp, CKp */
1188  struct GNUNET_HashCode dh;
1189  struct GNUNET_CRYPTO_EcdhePublicKey *DHRp;
1190 
1191  /* Try Next HK */
1192  t_hmac(&src->ax_header,
1193  sizeof(struct GNUNET_CADET_AxHeader) + esize,
1194  0,
1195  &ax->NHKr,
1196  &msg_hmac);
1197  if (0 != GNUNET_memcmp(&msg_hmac,
1198  &src->hmac))
1199  {
1200  /* Try the skipped keys, if that fails, we're out of luck. */
1201  return try_old_ax_keys(ax,
1202  dst,
1203  src,
1204  size);
1205  }
1206  HK = ax->HKr;
1207  ax->HKr = ax->NHKr;
1208  t_h_decrypt(ax,
1209  src,
1210  &plaintext_header);
1211  Np = ntohl(plaintext_header.ax_header.Ns);
1212  PNp = ntohl(plaintext_header.ax_header.PNs);
1213  DHRp = &plaintext_header.ax_header.DHRs;
1214  store_ax_keys(ax,
1215  &HK,
1216  PNp);
1217 
1218  /* RKp, NHKp, CKp = KDF (HMAC-HASH (RK, DH (DHRp, DHRs))) */
1220  DHRp,
1221  &dh);
1222  t_ax_hmac_hash(&ax->RK,
1223  &hmac,
1224  &dh, sizeof(dh));
1225  GNUNET_CRYPTO_kdf(keys, sizeof(keys),
1226  ctx, sizeof(ctx),
1227  &hmac, sizeof(hmac),
1228  NULL);
1229 
1230  /* Commit "purported" keys */
1231  ax->RK = keys[0];
1232  ax->NHKr = keys[1];
1233  ax->CKr = keys[2];
1234  ax->DHRr = *DHRp;
1235  ax->Nr = 0;
1237  }
1238  else
1239  {
1240  t_h_decrypt(ax,
1241  src,
1242  &plaintext_header);
1243  Np = ntohl(plaintext_header.ax_header.Ns);
1244  PNp = ntohl(plaintext_header.ax_header.PNs);
1245  }
1246  if ((Np != ax->Nr) &&
1247  (GNUNET_OK != store_ax_keys(ax,
1248  &ax->HKr,
1249  Np)))
1250  {
1251  /* Try the skipped keys, if that fails, we're out of luck. */
1252  return try_old_ax_keys(ax,
1253  dst,
1254  src,
1255  size);
1256  }
1257 
1258  t_ax_decrypt(ax,
1259  dst,
1260  &src[1],
1261  esize);
1262  ax->Nr = Np + 1;
1263  return esize;
1264 }
1265 
1266 
1276 static int
1278  uint32_t key,
1279  void *value)
1280 {
1281  struct CadetChannel *ch = value;
1282 
1283  GCCH_tunnel_up(ch);
1284  return GNUNET_OK;
1285 }
1286 
1287 
1295 void
1297  enum CadetTunnelEState state)
1298 {
1299  enum CadetTunnelEState old = t->estate;
1300 
1301  t->estate = state;
1303  "%s estate changed from %s to %s\n",
1304  GCT_2s(t),
1305  estate2s(old),
1306  estate2s(state));
1307 
1308  if ((CADET_TUNNEL_KEY_OK != old) &&
1309  (CADET_TUNNEL_KEY_OK == t->estate))
1310  {
1311  if (NULL != t->kx_task)
1312  {
1314  t->kx_task = NULL;
1315  }
1316  /* notify all channels that have been waiting */
1319  t);
1320  if (NULL != t->send_task)
1323  t);
1324  }
1325 }
1326 
1327 
1336 static void
1338  struct CadetTConnection *ct,
1339  struct CadetTunnelAxolotl *ax)
1340 {
1341  struct CadetConnection *cc;
1342  struct GNUNET_MQ_Envelope *env;
1345 
1347  return; /* only Alice may send KX */
1348  if ((NULL == ct) ||
1349  (GNUNET_NO == ct->is_ready))
1350  ct = get_ready_connection(t);
1351  if (NULL == ct)
1352  {
1354  "Wanted to send %s in state %s, but no connection is ready, deferring\n",
1355  GCT_2s(t),
1356  estate2s(t->estate));
1358  return;
1359  }
1360  cc = ct->cc;
1361  env = GNUNET_MQ_msg(msg,
1363  flags = GNUNET_CADET_KX_FLAG_FORCE_REPLY; /* always for KX */
1364  msg->flags = htonl(flags);
1365  msg->cid = *GCC_get_id(cc);
1367  &msg->ephemeral_key);
1368 #if DEBUG_KX
1369  msg->ephemeral_key_XXX = ax->kx_0;
1370  msg->private_key_XXX = *my_private_key;
1371 #endif
1373  "Sending KX message to %s with ephemeral %s on CID %s\n",
1374  GCT_2s(t),
1375  GNUNET_e2s(&msg->ephemeral_key),
1378  &msg->ratchet_key);
1385  else if (CADET_TUNNEL_KEY_AX_RECV == t->estate)
1388  GCC_transmit(cc,
1389  env);
1391  "# KX transmitted",
1392  1,
1393  GNUNET_NO);
1394 }
1395 
1396 
1407 static void
1409  struct CadetTConnection *ct,
1410  struct CadetTunnelAxolotl *ax,
1411  int force_reply)
1412 {
1413  struct CadetConnection *cc;
1414  struct GNUNET_MQ_Envelope *env;
1416  enum GNUNET_CADET_KX_Flags flags;
1417 
1418  if ((NULL == ct) ||
1419  (GNUNET_NO == ct->is_ready))
1420  ct = get_ready_connection(t);
1421  if (NULL == ct)
1422  {
1424  "Wanted to send KX_AUTH on %s, but no connection is ready, deferring\n",
1425  GCT_2s(t));
1427  t->kx_auth_requested = GNUNET_YES; /* queue KX_AUTH independent of estate */
1428  return;
1429  }
1430  t->kx_auth_requested = GNUNET_NO; /* clear flag */
1431  cc = ct->cc;
1432  env = GNUNET_MQ_msg(msg,
1434  flags = GNUNET_CADET_KX_FLAG_NONE;
1435  if (GNUNET_YES == force_reply)
1437  msg->kx.flags = htonl(flags);
1438  msg->kx.cid = *GCC_get_id(cc);
1440  &msg->kx.ephemeral_key);
1442  &msg->kx.ratchet_key);
1443 #if DEBUG_KX
1444  msg->kx.ephemeral_key_XXX = ax->kx_0;
1445  msg->kx.private_key_XXX = *my_private_key;
1446  msg->r_ephemeral_key_XXX = ax->last_ephemeral;
1447 #endif
1449  "Sending KX_AUTH message to %s with ephemeral %s on CID %s\n",
1450  GCT_2s(t),
1451  GNUNET_e2s(&msg->kx.ephemeral_key),
1453 
1454  /* Compute authenticator (this is the main difference to #send_kx()) */
1455  GNUNET_CRYPTO_hash(&ax->RK,
1456  sizeof(ax->RK),
1457  &msg->auth);
1458  /* Compute when to be triggered again; actual job will
1459  be scheduled via #connection_ready_cb() */
1460  t->kx_retry_delay
1462  t->next_kx_attempt
1464 
1465  /* Send via cc, mark it as unready */
1467 
1468  /* Update state machine, unless we are already OK */
1469  if (CADET_TUNNEL_KEY_OK != t->estate)
1472  GCC_transmit(cc,
1473  env);
1475  "# KX_AUTH transmitted",
1476  1,
1477  GNUNET_NO);
1478 }
1479 
1480 
1486 static void
1488 {
1489  while (NULL != ax->skipped_head)
1490  delete_skipped_key(ax,
1491  ax->skipped_head);
1492  GNUNET_assert(0 == ax->skipped);
1495 }
1496 
1497 
1511 static int
1513  const struct GNUNET_PeerIdentity *pid,
1514  const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key,
1515  const struct GNUNET_CRYPTO_EcdhePublicKey *ratchet_key)
1516 {
1517  struct GNUNET_HashCode key_material[3];
1518  struct GNUNET_CRYPTO_SymmetricSessionKey keys[5];
1519  const char salt[] = "CADET Axolotl salt";
1520  int am_I_alice;
1521 
1522  if (GNUNET_SYSERR == (am_I_alice = alice_or_betty(pid)))
1523  {
1524  GNUNET_break_op(0);
1525  return GNUNET_SYSERR;
1526  }
1527  if (0 == GNUNET_memcmp(&ax->DHRr,
1528  ratchet_key))
1529  {
1531  "# Ratchet key already known",
1532  1,
1533  GNUNET_NO);
1535  "Ratchet key already known. Ignoring KX.\n");
1536  return GNUNET_NO;
1537  }
1538 
1539  ax->DHRr = *ratchet_key;
1540  ax->last_ephemeral = *ephemeral_key;
1541  /* ECDH A B0 */
1542  if (GNUNET_YES == am_I_alice)
1543  {
1545  ephemeral_key, /* B0 */
1546  &key_material[0]);
1547  }
1548  else
1549  {
1550  GNUNET_CRYPTO_ecdh_eddsa(&ax->kx_0, /* b0 */
1551  &pid->public_key, /* A */
1552  &key_material[0]);
1553  }
1554  /* ECDH A0 B */
1555  if (GNUNET_YES == am_I_alice)
1556  {
1557  GNUNET_CRYPTO_ecdh_eddsa(&ax->kx_0, /* a0 */
1558  &pid->public_key, /* B */
1559  &key_material[1]);
1560  }
1561  else
1562  {
1564  ephemeral_key, /* A0 */
1565  &key_material[1]);
1566  }
1567 
1568  /* ECDH A0 B0 */
1569  GNUNET_CRYPTO_ecc_ecdh(&ax->kx_0, /* a0 or b0 */
1570  ephemeral_key, /* B0 or A0 */
1571  &key_material[2]);
1572  /* KDF */
1573  GNUNET_CRYPTO_kdf(keys, sizeof(keys),
1574  salt, sizeof(salt),
1575  &key_material, sizeof(key_material),
1576  NULL);
1577 
1578  if (0 == memcmp(&ax->RK,
1579  &keys[0],
1580  sizeof(ax->RK)))
1581  {
1583  "Root key already known. Ignoring KX.\n");
1585  "# Root key already known",
1586  1,
1587  GNUNET_NO);
1588  return GNUNET_NO;
1589  }
1590 
1591  ax->RK = keys[0];
1592  if (GNUNET_YES == am_I_alice)
1593  {
1594  ax->HKr = keys[1];
1595  ax->NHKs = keys[2];
1596  ax->NHKr = keys[3];
1597  ax->CKr = keys[4];
1598  ax->ratchet_flag = GNUNET_YES;
1599  }
1600  else
1601  {
1602  ax->HKs = keys[1];
1603  ax->NHKr = keys[2];
1604  ax->NHKs = keys[3];
1605  ax->CKs = keys[4];
1606  ax->ratchet_flag = GNUNET_NO;
1607  ax->ratchet_expiration
1609  ratchet_time);
1610  }
1611  return GNUNET_OK;
1612 }
1613 
1614 
1620 static void
1621 retry_kx(void *cls)
1622 {
1623  struct CadetTunnel *t = cls;
1624  struct CadetTunnelAxolotl *ax;
1625 
1626  t->kx_task = NULL;
1628  "Trying to make KX progress on %s in state %s\n",
1629  GCT_2s(t),
1630  estate2s(t->estate));
1631  switch (t->estate)
1632  {
1633  case CADET_TUNNEL_KEY_UNINITIALIZED: /* first attempt */
1634  case CADET_TUNNEL_KEY_AX_SENT: /* trying again */
1635  send_kx(t,
1636  NULL,
1637  &t->ax);
1638  break;
1639 
1642  /* We are responding, so only require reply
1643  if WE have a channel waiting. */
1644  if (NULL != t->unverified_ax)
1645  {
1646  /* Send AX_AUTH so we might get this one verified */
1647  ax = t->unverified_ax;
1648  }
1649  else
1650  {
1651  /* How can this be? */
1652  GNUNET_break(0);
1653  ax = &t->ax;
1654  }
1655  send_kx_auth(t,
1656  NULL,
1657  ax,
1658  (0 == GCT_count_channels(t))
1659  ? GNUNET_NO
1660  : GNUNET_YES);
1661  break;
1662 
1664  /* We are responding, so only require reply
1665  if WE have a channel waiting. */
1666  if (NULL != t->unverified_ax)
1667  {
1668  /* Send AX_AUTH so we might get this one verified */
1669  ax = t->unverified_ax;
1670  }
1671  else
1672  {
1673  /* How can this be? */
1674  GNUNET_break(0);
1675  ax = &t->ax;
1676  }
1677  send_kx_auth(t,
1678  NULL,
1679  ax,
1680  (0 == GCT_count_channels(t))
1681  ? GNUNET_NO
1682  : GNUNET_YES);
1683  break;
1684 
1685  case CADET_TUNNEL_KEY_OK:
1686  /* Must have been the *other* peer asking us to
1687  respond with a KX_AUTH. */
1688  if (NULL != t->unverified_ax)
1689  {
1690  /* Sending AX_AUTH in response to AX so we might get this one verified */
1691  ax = t->unverified_ax;
1692  }
1693  else
1694  {
1695  /* Sending AX_AUTH in response to AX_AUTH */
1696  ax = &t->ax;
1697  }
1698  send_kx_auth(t,
1699  NULL,
1700  ax,
1701  GNUNET_NO);
1702  break;
1703  }
1704 }
1705 
1706 
1715 void
1718 {
1719  struct CadetTunnel *t = ct->t;
1720  int ret;
1721 
1723  "# KX received",
1724  1,
1725  GNUNET_NO);
1726  if (GNUNET_YES ==
1728  {
1729  /* Betty/Bob is not allowed to send KX! */
1730  GNUNET_break_op(0);
1731  return;
1732  }
1734  "Received KX message from %s with ephemeral %s from %s on connection %s\n",
1735  GCT_2s(t),
1736  GNUNET_e2s(&msg->ephemeral_key),
1738  GCC_2s(ct->cc));
1739 #if 1
1740  if ((0 ==
1741  memcmp(&t->ax.DHRr,
1742  &msg->ratchet_key,
1743  sizeof(msg->ratchet_key))) &&
1744  (0 ==
1745  memcmp(&t->ax.last_ephemeral,
1746  &msg->ephemeral_key,
1747  sizeof(msg->ephemeral_key))))
1748 
1749  {
1751  "# Duplicate KX received",
1752  1,
1753  GNUNET_NO);
1754  send_kx_auth(t,
1755  ct,
1756  &t->ax,
1757  GNUNET_NO);
1758  return;
1759  }
1760 #endif
1761  /* We only keep ONE unverified KX around, so if there is an existing one,
1762  clean it up. */
1763  if (NULL != t->unverified_ax)
1764  {
1765  if ((0 ==
1766  memcmp(&t->unverified_ax->DHRr,
1767  &msg->ratchet_key,
1768  sizeof(msg->ratchet_key))) &&
1769  (0 ==
1770  memcmp(&t->unverified_ax->last_ephemeral,
1771  &msg->ephemeral_key,
1772  sizeof(msg->ephemeral_key))))
1773  {
1775  "# Duplicate unverified KX received",
1776  1,
1777  GNUNET_NO);
1778 #if 1
1779  send_kx_auth(t,
1780  ct,
1781  t->unverified_ax,
1782  GNUNET_NO);
1783  return;
1784 #endif
1785  }
1787  "Dropping old unverified KX state.\n");
1789  "# Unverified KX dropped for fresh KX",
1790  1,
1791  GNUNET_NO);
1793  memset(t->unverified_ax,
1794  0,
1795  sizeof(struct CadetTunnelAxolotl));
1796  }
1797  else
1798  {
1800  "Creating fresh unverified KX for %s\n",
1801  GCT_2s(t));
1803  "# Fresh KX setup",
1804  1,
1805  GNUNET_NO);
1807  }
1808  /* Set as the 'current' RK/DHRr the one we are currently using,
1809  so that the duplicate-detection logic of
1810  #update_ax_by_kx can work. */
1811  t->unverified_ax->RK = t->ax.RK;
1812  t->unverified_ax->DHRr = t->ax.DHRr;
1813  t->unverified_ax->DHRs = t->ax.DHRs;
1814  t->unverified_ax->kx_0 = t->ax.kx_0;
1815  t->unverified_attempts = 0;
1816 
1817  /* Update 'ax' by the new key material */
1818  ret = update_ax_by_kx(t->unverified_ax,
1819  GCP_get_id(t->destination),
1820  &msg->ephemeral_key,
1821  &msg->ratchet_key);
1822  GNUNET_break(GNUNET_SYSERR != ret);
1823  if (GNUNET_OK != ret)
1824  {
1826  "# Useless KX",
1827  1,
1828  GNUNET_NO);
1829  return; /* duplicate KX, nothing to do */
1830  }
1831  /* move ahead in our state machine */
1835  else if (CADET_TUNNEL_KEY_AX_SENT == t->estate)
1838 
1839  /* KX is still not done, try again our end. */
1840  if (CADET_TUNNEL_KEY_OK != t->estate)
1841  {
1842  if (NULL != t->kx_task)
1844  t->kx_task
1846  t);
1847  }
1848 }
1849 
1850 
1851 #if DEBUG_KX
1852 static void
1853 check_ee(const struct GNUNET_CRYPTO_EcdhePrivateKey *e1,
1854  const struct GNUNET_CRYPTO_EcdhePrivateKey *e2)
1855 {
1856  struct GNUNET_CRYPTO_EcdhePublicKey p1;
1857  struct GNUNET_CRYPTO_EcdhePublicKey p2;
1858  struct GNUNET_HashCode hc1;
1859  struct GNUNET_HashCode hc2;
1860 
1862  &p1);
1864  &p2);
1867  &p2,
1868  &hc1));
1871  &p1,
1872  &hc2));
1873  GNUNET_break(0 == GNUNET_memcmp(&hc1,
1874  &hc2));
1875 }
1876 
1877 
1878 static void
1879 check_ed(const struct GNUNET_CRYPTO_EcdhePrivateKey *e1,
1880  const struct GNUNET_CRYPTO_EddsaPrivateKey *e2)
1881 {
1882  struct GNUNET_CRYPTO_EcdhePublicKey p1;
1883  struct GNUNET_CRYPTO_EddsaPublicKey p2;
1884  struct GNUNET_HashCode hc1;
1885  struct GNUNET_HashCode hc2;
1886 
1888  &p1);
1890  &p2);
1893  &p2,
1894  &hc1));
1897  &p1,
1898  &hc2));
1899  GNUNET_break(0 == GNUNET_memcmp(&hc1,
1900  &hc2));
1901 }
1902 
1903 
1904 static void
1905 test_crypto_bug(const struct GNUNET_CRYPTO_EcdhePrivateKey *e1,
1906  const struct GNUNET_CRYPTO_EcdhePrivateKey *e2,
1907  const struct GNUNET_CRYPTO_EddsaPrivateKey *d1,
1908  const struct GNUNET_CRYPTO_EddsaPrivateKey *d2)
1909 {
1910  check_ee(e1, e2);
1911  check_ed(e1, d2);
1912  check_ed(e2, d1);
1913 }
1914 
1915 #endif
1916 
1917 
1924 void
1927 {
1928  struct CadetTunnel *t = ct->t;
1929  struct CadetTunnelAxolotl ax_tmp;
1930  struct GNUNET_HashCode kx_auth;
1931  int ret;
1932 
1934  "# KX_AUTH received",
1935  1,
1936  GNUNET_NO);
1937  if ((CADET_TUNNEL_KEY_UNINITIALIZED == t->estate) ||
1939  {
1940  /* Confusing, we got a KX_AUTH before we even send our own
1941  KX. This should not happen. We'll send our own KX ASAP anyway,
1942  so let's ignore this here. */
1943  GNUNET_break_op(0);
1944  return;
1945  }
1947  "Handling KX_AUTH message from %s with ephemeral %s\n",
1948  GCT_2s(t),
1949  GNUNET_e2s(&msg->kx.ephemeral_key));
1950  /* We do everything in ax_tmp until we've checked the authentication
1951  so we don't clobber anything we care about by accident. */
1952  ax_tmp = t->ax;
1953 
1954  /* Update 'ax' by the new key material */
1955  ret = update_ax_by_kx(&ax_tmp,
1956  GCP_get_id(t->destination),
1957  &msg->kx.ephemeral_key,
1958  &msg->kx.ratchet_key);
1959  if (GNUNET_OK != ret)
1960  {
1961  if (GNUNET_NO == ret)
1963  "# redundant KX_AUTH received",
1964  1,
1965  GNUNET_NO);
1966  else
1967  GNUNET_break(0); /* connect to self!? */
1968  return;
1969  }
1970  GNUNET_CRYPTO_hash(&ax_tmp.RK,
1971  sizeof(ax_tmp.RK),
1972  &kx_auth);
1973  if (0 != GNUNET_memcmp(&kx_auth,
1974  &msg->auth))
1975  {
1976  /* This KX_AUTH is not using the latest KX/KX_AUTH data
1977  we transmitted to the sender, refuse it, try KX again. */
1979  "# KX_AUTH not using our last KX received (auth failure)",
1980  1,
1981  GNUNET_NO);
1983  "KX AUTH mismatch!\n");
1984 #if DEBUG_KX
1985  {
1986  struct GNUNET_CRYPTO_EcdhePublicKey ephemeral_key;
1987 
1989  &ephemeral_key);
1990  if (0 != GNUNET_memcmp(&ephemeral_key,
1991  &msg->r_ephemeral_key_XXX))
1992  {
1994  "My ephemeral is %s!\n",
1995  GNUNET_e2s(&ephemeral_key));
1997  "Response is for ephemeral %s!\n",
1998  GNUNET_e2s(&msg->r_ephemeral_key_XXX));
1999  }
2000  else
2001  {
2002  test_crypto_bug(&ax_tmp.kx_0,
2003  &msg->kx.ephemeral_key_XXX,
2005  &msg->kx.private_key_XXX);
2006  }
2007  }
2008 #endif
2009  if (NULL == t->kx_task)
2010  t->kx_task
2012  &retry_kx,
2013  t);
2014  return;
2015  }
2016  /* Yep, we're good. */
2017  t->ax = ax_tmp;
2018  if (NULL != t->unverified_ax)
2019  {
2020  /* We got some "stale" KX before, drop that. */
2023  t->unverified_ax = NULL;
2024  }
2025 
2026  /* move ahead in our state machine */
2027  switch (t->estate)
2028  {
2031  /* Checked above, this is impossible. */
2032  GNUNET_assert(0);
2033  break;
2034 
2035  case CADET_TUNNEL_KEY_AX_SENT: /* This is the normal case */
2036  case CADET_TUNNEL_KEY_AX_SENT_AND_RECV: /* both peers started KX */
2037  case CADET_TUNNEL_KEY_AX_AUTH_SENT: /* both peers now did KX_AUTH */
2040  break;
2041 
2042  case CADET_TUNNEL_KEY_OK:
2043  /* Did not expect another KX_AUTH, but so what, still acceptable.
2044  Nothing to do here. */
2045  break;
2046  }
2047  if (0 != (GNUNET_CADET_KX_FLAG_FORCE_REPLY & ntohl(msg->kx.flags)))
2048  {
2049  send_kx_auth(t,
2050  NULL,
2051  &t->ax,
2052  GNUNET_NO);
2053  }
2054 }
2055 
2056 
2057 
2058 /* ************************************** end core crypto ***************************** */
2059 
2060 
2069 {
2070 #define HIGH_BIT 0x8000000
2072  uint32_t ctn;
2073  int cmp;
2074  uint32_t highbit;
2075 
2076  cmp = GNUNET_memcmp(&my_full_id,
2078  if (0 < cmp)
2079  highbit = HIGH_BIT;
2080  else if (0 > cmp)
2081  highbit = 0;
2082  else
2083  GNUNET_assert(0); // loopback must never go here!
2084  ctn = ntohl(t->next_ctn.cn);
2085  while (NULL !=
2087  ctn | highbit))
2088  {
2089  ctn = ((ctn + 1) & (~HIGH_BIT));
2090  }
2091  t->next_ctn.cn = htonl((ctn + 1) & (~HIGH_BIT));
2092  ret.cn = htonl(ctn | highbit);
2093  return ret;
2094 }
2095 
2096 
2108  struct CadetChannel *ch)
2109 {
2111 
2112  ctn = get_next_free_ctn(t);
2113  if (NULL != t->destroy_task)
2114  {
2115  GNUNET_SCHEDULER_cancel(t->destroy_task);
2116  t->destroy_task = NULL;
2117  }
2120  ntohl(ctn.cn),
2121  ch,
2124  "Adding %s to %s\n",
2125  GCCH_2s(ch),
2126  GCT_2s(t));
2127  switch (t->estate)
2128  {
2130  /* waiting for connection to start KX */
2131  break;
2132 
2136  /* we're currently waiting for KX to complete */
2137  break;
2138 
2140  /* waiting for OTHER peer to send us data,
2141  we might need to prompt more aggressively! */
2142  if (NULL == t->kx_task)
2143  t->kx_task
2144  = GNUNET_SCHEDULER_add_at(t->next_kx_attempt,
2145  &retry_kx,
2146  t);
2147  break;
2148 
2149  case CADET_TUNNEL_KEY_OK:
2150  /* We are ready. Tell the new channel that we are up. */
2151  GCCH_tunnel_up(ch);
2152  break;
2153  }
2154  return ctn;
2155 }
2156 
2157 
2164 void
2166 {
2167  struct CadetTunnel *t = ct->t;
2168 
2169  if (GNUNET_YES == ct->is_ready)
2170  {
2173  ct);
2174  t->num_ready_connections--;
2175  }
2176  else
2177  {
2180  ct);
2181  t->num_busy_connections--;
2182  }
2183  GNUNET_free(ct);
2184 }
2185 
2186 
2193 static void
2195  struct CadetTConnection *ct)
2196 {
2197  struct CadetTunnel *t = cls;
2198  struct CadetConnection *cc = ct->cc;
2199 
2200  GNUNET_assert(ct->t == t);
2201  GCT_connection_lost(ct);
2203 }
2204 
2205 
2211 static void
2212 destroy_tunnel(void *cls)
2213 {
2214  struct CadetTunnel *t = cls;
2215  struct CadetTunnelQueueEntry *tq;
2216 
2217  t->destroy_task = NULL;
2219  "Destroying idle %s\n",
2220  GCT_2s(t));
2224  t);
2226  GNUNET_assert(NULL == t->connection_busy_head);
2227  while (NULL != (tq = t->tq_head))
2228  {
2229  if (NULL != tq->cont)
2230  tq->cont(tq->cont_cls,
2231  NULL);
2232  GCT_send_cancel(tq);
2233  }
2235  t);
2237  if (NULL != t->maintain_connections_task)
2238  {
2240  t->maintain_connections_task = NULL;
2241  }
2242  if (NULL != t->send_task)
2243  {
2245  t->send_task = NULL;
2246  }
2247  if (NULL != t->kx_task)
2248  {
2250  t->kx_task = NULL;
2251  }
2252  GNUNET_MST_destroy(t->mst);
2253  GNUNET_MQ_destroy(t->mq);
2254  if (NULL != t->unverified_ax)
2255  {
2258  }
2259  cleanup_ax(&t->ax);
2260  GNUNET_assert(NULL == t->destroy_task);
2261  GNUNET_free(t);
2262 }
2263 
2264 
2272 void
2274  struct CadetChannel *ch,
2276 {
2278  "Removing %s from %s\n",
2279  GCCH_2s(ch),
2280  GCT_2s(t));
2283  ntohl(ctn.cn),
2284  ch));
2285  if ((0 ==
2286  GCT_count_channels(t)) &&
2287  (NULL == t->destroy_task))
2288  {
2289  t->destroy_task
2291  &destroy_tunnel,
2292  t);
2293  }
2294 }
2295 
2296 
2305 static int
2307  uint32_t key,
2308  void *value)
2309 {
2310  struct CadetChannel *ch = value;
2311 
2313  NULL);
2314  return GNUNET_OK;
2315 }
2316 
2317 
2323 void
2325 {
2329  t);
2330  GNUNET_assert(0 ==
2331  GCT_count_channels(t));
2332  if (NULL != t->destroy_task)
2333  {
2335  t->destroy_task = NULL;
2336  }
2337  destroy_tunnel(t);
2338 }
2339 
2340 
2348 static void
2350  struct CadetTConnection *ct)
2351 {
2352  struct CadetTunnelQueueEntry *tq;
2353 
2355  tq = t->tq_head;
2356  if (NULL == tq)
2357  {
2358  /* no messages pending right now */
2360  "Not sending payload of %s on ready %s (nothing pending)\n",
2361  GCT_2s(t),
2362  GCC_2s(ct->cc));
2363  return;
2364  }
2365  /* ready to send message 'tq' on tunnel 'ct' */
2366  GNUNET_assert(t == tq->t);
2368  t->tq_tail,
2369  tq);
2370  if (NULL != tq->cid)
2371  *tq->cid = *GCC_get_id(ct->cc);
2374  "Sending payload of %s on %s\n",
2375  GCT_2s(t),
2376  GCC_2s(ct->cc));
2377  GCC_transmit(ct->cc,
2378  tq->env);
2379  if (NULL != tq->cont)
2380  tq->cont(tq->cont_cls,
2381  GCC_get_id(ct->cc));
2382  GNUNET_free(tq);
2383 }
2384 
2385 
2394 static void
2396  int is_ready)
2397 {
2398  struct CadetTConnection *ct = cls;
2399  struct CadetTunnel *t = ct->t;
2400 
2401  if (GNUNET_NO == is_ready)
2402  {
2404  "%s no longer ready for %s\n",
2405  GCC_2s(ct->cc),
2406  GCT_2s(t));
2408  return;
2409  }
2413  ct);
2415  t->num_busy_connections--;
2416  ct->is_ready = GNUNET_YES;
2419  ct);
2420  t->num_ready_connections++;
2421 
2423  "%s now ready for %s in state %s\n",
2424  GCC_2s(ct->cc),
2425  GCT_2s(t),
2426  estate2s(t->estate));
2427  switch (t->estate)
2428  {
2430  /* Do not begin KX if WE have no channels waiting! */
2432  return; /* wait for timeout before retrying */
2433  /* We are uninitialized, just transmit immediately,
2434  without undue delay. */
2435  if (NULL != t->kx_task)
2436  {
2438  t->kx_task = NULL;
2439  }
2440  send_kx(t,
2441  ct,
2442  &t->ax);
2443  if ((0 ==
2444  GCT_count_channels(t)) &&
2445  (NULL == t->destroy_task))
2446  {
2447  t->destroy_task
2449  &destroy_tunnel,
2450  t);
2451  }
2452  break;
2453 
2458  /* we're currently waiting for KX to complete, schedule job */
2459  if (NULL == t->kx_task)
2460  t->kx_task
2462  &retry_kx,
2463  t);
2464  break;
2465 
2466  case CADET_TUNNEL_KEY_OK:
2467  if (GNUNET_YES == t->kx_auth_requested)
2468  {
2470  return; /* wait for timeout */
2471  if (NULL != t->kx_task)
2472  {
2474  t->kx_task = NULL;
2475  }
2476  send_kx_auth(t,
2477  ct,
2478  &t->ax,
2479  GNUNET_NO);
2480  return;
2481  }
2483  ct);
2484  break;
2485  }
2486 }
2487 
2488 
2497 static void
2499 {
2500  struct CadetTunnel *t = cls;
2501  struct CadetTConnection *ct;
2502 
2503  t->send_task = NULL;
2504  if (NULL == t->tq_head)
2505  return; /* no messages pending right now */
2506  ct = get_ready_connection(t);
2507  if (NULL == ct)
2508  return; /* no connections ready */
2510  ct);
2511 }
2512 
2513 
2522  unsigned int min_length;
2523 
2527  unsigned int max_length;
2528 
2533 
2538 
2543 
2549 
2553  double worst_score;
2554 
2559 };
2560 
2561 
2569 static void
2571  struct CadetTConnection *ct)
2572 {
2573  struct EvaluationSummary *es = cls;
2574  struct CadetConnection *cc = ct->cc;
2575  unsigned int ct_length;
2576  struct CadetPeerPath *ps;
2577  const struct CadetConnectionMetrics *metrics;
2578  GNUNET_CONTAINER_HeapCostType ct_desirability;
2579  struct GNUNET_TIME_Relative uptime;
2580  struct GNUNET_TIME_Relative last_use;
2581  double score;
2582  double success_rate;
2583 
2584  ps = GCC_get_path(cc,
2585  &ct_length);
2587  "Evaluating path %s of existing %s\n",
2588  GCPP_2s(ps),
2589  GCC_2s(cc));
2590  if (ps == es->path)
2591  {
2593  "Ignoring duplicate path %s.\n",
2594  GCPP_2s(es->path));
2595  es->duplicate = GNUNET_YES;
2596  return;
2597  }
2598  if (NULL != es->path)
2599  {
2600  int duplicate = GNUNET_YES;
2601 
2602  for (unsigned int i = 0; i < ct_length; i++)
2603  {
2605  if (GCPP_get_peer_at_offset(es->path,
2606  i) !=
2608  i))
2609  {
2610  duplicate = GNUNET_NO;
2611  break;
2612  }
2613  }
2614  if (GNUNET_YES == duplicate)
2615  {
2617  "Ignoring overlapping path %s.\n",
2618  GCPP_2s(es->path));
2619  es->duplicate = GNUNET_YES;
2620  return;
2621  }
2622  else
2623  {
2625  "Known path %s differs from proposed path\n",
2626  GCPP_2s(ps));
2627  }
2628  }
2629 
2630  ct_desirability = GCPP_get_desirability(ps);
2631  metrics = GCC_get_metrics(cc);
2632  uptime = GNUNET_TIME_absolute_get_duration(metrics->age);
2633  last_use = GNUNET_TIME_absolute_get_duration(metrics->last_use);
2634  /* We add 1.0 here to avoid division by zero. */
2635  success_rate = (metrics->num_acked_transmissions + 1.0) / (metrics->num_successes + 1.0);
2636  score
2637  = ct_desirability
2638  + 100.0 / (1.0 + ct_length) /* longer paths = better */
2639  + sqrt(uptime.rel_value_us / 60000000LL) /* larger uptime = better */
2640  - last_use.rel_value_us / 1000L; /* longer idle = worse */
2641  score *= success_rate; /* weigh overall by success rate */
2642 
2643  if ((NULL == es->worst) ||
2644  (score < es->worst_score))
2645  {
2646  es->worst = ct;
2647  es->worst_score = score;
2648  }
2649  es->min_length = GNUNET_MIN(es->min_length,
2650  ct_length);
2651  es->max_length = GNUNET_MAX(es->max_length,
2652  ct_length);
2653  es->min_desire = GNUNET_MIN(es->min_desire,
2654  ct_desirability);
2655  es->max_desire = GNUNET_MAX(es->max_desire,
2656  ct_desirability);
2657 }
2658 
2659 
2669 static int
2671  struct CadetPeerPath *path,
2672  unsigned int off)
2673 {
2674  struct CadetTunnel *t = cls;
2675  struct EvaluationSummary es;
2676  struct CadetTConnection *ct;
2677 
2678  GNUNET_assert(off < GCPP_get_length(path));
2680  off) == t->destination);
2681  es.min_length = UINT_MAX;
2682  es.max_length = 0;
2683  es.max_desire = 0;
2684  es.min_desire = UINT64_MAX;
2685  es.path = path;
2686  es.duplicate = GNUNET_NO;
2687  es.worst = NULL;
2688 
2689  /* Compute evaluation summary over existing connections. */
2691  "Evaluating proposed path %s for target %s\n",
2692  GCPP_2s(path),
2693  GCT_2s(t));
2694  /* FIXME: suspect this does not ACTUALLY iterate
2695  over all existing paths, otherwise dup detection
2696  should work!!! */
2699  &es);
2700  if (GNUNET_YES == es.duplicate)
2701  return GNUNET_YES;
2702 
2703  /* FIXME: not sure we should really just count
2704  'num_connections' here, as they may all have
2705  consistently failed to connect. */
2706 
2707  /* We iterate by increasing path length; if we have enough paths and
2708  this one is more than twice as long than what we are currently
2709  using, then ignore all of these super-long ones! */
2711  (es.min_length * 2 < off) &&
2712  (es.max_length < off))
2713  {
2715  "Ignoring paths of length %u, they are way too long.\n",
2716  es.min_length * 2);
2717  return GNUNET_NO;
2718  }
2719  /* If we have enough paths and this one looks no better, ignore it. */
2721  (es.min_length < GCPP_get_length(path)) &&
2722  (es.min_desire > GCPP_get_desirability(path)) &&
2723  (es.max_length < off))
2724  {
2726  "Ignoring path (%u/%llu) to %s, got something better already.\n",
2727  GCPP_get_length(path),
2728  (unsigned long long)GCPP_get_desirability(path),
2729  GCP_2s(t->destination));
2730  return GNUNET_YES;
2731  }
2732 
2733  /* Path is interesting (better by some metric, or we don't have
2734  enough paths yet). */
2735  ct = GNUNET_new(struct CadetTConnection);
2737  ct->t = t;
2738  ct->cc = GCC_create(t->destination,
2739  path,
2740  off,
2741  ct,
2743  ct);
2744 
2745  /* FIXME: schedule job to kill connection (and path?) if it takes
2746  too long to get ready! (And track performance data on how long
2747  other connections took with the tunnel!)
2748  => Note: to be done within 'connection'-logic! */
2751  ct);
2752  t->num_busy_connections++;
2754  "Found interesting path %s for %s, created %s\n",
2755  GCPP_2s(path),
2756  GCT_2s(t),
2757  GCC_2s(ct->cc));
2758  return GNUNET_YES;
2759 }
2760 
2761 
2775 static void
2777 {
2778  struct CadetTunnel *t = cls;
2779  struct GNUNET_TIME_Relative delay;
2780  struct EvaluationSummary es;
2781 
2782  t->maintain_connections_task = NULL;
2784  "Performing connection maintenance for %s.\n",
2785  GCT_2s(t));
2786 
2787  es.min_length = UINT_MAX;
2788  es.max_length = 0;
2789  es.max_desire = 0;
2790  es.min_desire = UINT64_MAX;
2791  es.path = NULL;
2792  es.worst = NULL;
2793  es.duplicate = GNUNET_NO;
2796  &es);
2797  if ((NULL != es.worst) &&
2799  {
2800  /* Clear out worst-performing connection 'es.worst'. */
2802  es.worst);
2803  }
2804 
2805  /* Consider additional paths */
2806  (void)GCP_iterate_paths(t->destination,
2808  t);
2809 
2810  /* FIXME: calculate when to try again based on how well we are doing;
2811  in particular, if we have to few connections, we might be able
2812  to do without this (as PATHS should tell us whenever a new path
2813  is available instantly; however, need to make sure this job is
2814  restarted after that happens).
2815  Furthermore, if the paths we do know are in a reasonably narrow
2816  quality band and are plentyful, we might also consider us stabilized
2817  and then reduce the frequency accordingly. */
2818  delay = GNUNET_TIME_UNIT_MINUTES;
2822  t);
2823 }
2824 
2825 
2834 void
2836  struct CadetPeerPath *p,
2837  unsigned int off)
2838 {
2840  "Considering %s for %s (offset %u)\n",
2841  GCPP_2s(p),
2842  GCT_2s(t),
2843  off);
2844  (void)consider_path_cb(t,
2845  p,
2846  off);
2847 }
2848 
2849 
2856 static void
2858  const struct GNUNET_MessageHeader *msg)
2859 {
2860  struct CadetTunnel *t = cls;
2861 
2863  "Received KEEPALIVE on %s\n",
2864  GCT_2s(t));
2866  "# keepalives received",
2867  1,
2868  GNUNET_NO);
2869 }
2870 
2871 
2879 static int
2882 {
2883  return GNUNET_OK;
2884 }
2885 
2886 
2894 static void
2897 {
2898  struct CadetTunnel *t = cls;
2899  struct CadetChannel *ch;
2900 
2901  ch = lookup_channel(t,
2902  msg->ctn);
2903  if (NULL == ch)
2904  {
2905  /* We don't know about such a channel, might have been destroyed on our
2906  end in the meantime, or never existed. Send back a DESTROY. */
2908  "Received %u bytes of application data for unknown channel %u, sending DESTROY\n",
2909  (unsigned int)(ntohs(msg->header.size) - sizeof(*msg)),
2910  ntohl(msg->ctn.cn));
2912  msg->ctn);
2913  return;
2914  }
2916  GCC_get_id(t->current_ct->cc),
2917  msg);
2918 }
2919 
2920 
2929 static void
2931  const struct GNUNET_CADET_ChannelDataAckMessage *ack)
2932 {
2933  struct CadetTunnel *t = cls;
2934  struct CadetChannel *ch;
2935 
2936  ch = lookup_channel(t,
2937  ack->ctn);
2938  if (NULL == ch)
2939  {
2940  /* We don't know about such a channel, might have been destroyed on our
2941  end in the meantime, or never existed. Send back a DESTROY. */
2943  "Received DATA_ACK for unknown channel %u, sending DESTROY\n",
2944  ntohl(ack->ctn.cn));
2946  ack->ctn);
2947  return;
2948  }
2950  GCC_get_id(t->current_ct->cc),
2951  ack);
2952 }
2953 
2954 
2962 static void
2964  const struct GNUNET_CADET_ChannelOpenMessage *copen)
2965 {
2966  struct CadetTunnel *t = cls;
2967  struct CadetChannel *ch;
2968 
2970  ntohl(copen->ctn.cn));
2971  if (NULL != ch)
2972  {
2974  "Received duplicate channel CHANNEL_OPEN on h_port %s from %s (%s), resending ACK\n",
2975  GNUNET_h2s(&copen->h_port),
2976  GCT_2s(t),
2977  GCCH_2s(ch));
2979  GCC_get_id(t->current_ct->cc));
2980  return;
2981  }
2983  "Received CHANNEL_OPEN on h_port %s from %s\n",
2984  GNUNET_h2s(&copen->h_port),
2985  GCT_2s(t));
2987  copen->ctn,
2988  &copen->h_port,
2989  ntohl(copen->opt));
2990  if (NULL != t->destroy_task)
2991  {
2993  t->destroy_task = NULL;
2994  }
2997  ntohl(copen->ctn.cn),
2998  ch,
3000 }
3001 
3002 
3009 void
3012 {
3014 
3016  "Sending DESTORY message for channel ID %u\n",
3017  ntohl(ctn.cn));
3018  msg.header.size = htons(sizeof(msg));
3020  msg.reserved = htonl(0);
3021  msg.ctn = ctn;
3022  GCT_send(t,
3023  &msg.header,
3024  NULL,
3025  NULL);
3026 }
3027 
3028 
3037 static void
3039  const struct GNUNET_CADET_ChannelOpenAckMessage *cm)
3040 {
3041  struct CadetTunnel *t = cls;
3042  struct CadetChannel *ch;
3043 
3044  ch = lookup_channel(t,
3045  cm->ctn);
3046  if (NULL == ch)
3047  {
3048  /* We don't know about such a channel, might have been destroyed on our
3049  end in the meantime, or never existed. Send back a DESTROY. */
3051  "Received channel OPEN_ACK for unknown channel %u, sending DESTROY\n",
3052  ntohl(cm->ctn.cn));
3054  cm->ctn);
3055  return;
3056  }
3058  "Received channel OPEN_ACK on channel %s from %s\n",
3059  GCCH_2s(ch),
3060  GCT_2s(t));
3062  GCC_get_id(t->current_ct->cc),
3063  &cm->port);
3064 }
3065 
3066 
3074 static void
3076  const struct GNUNET_CADET_ChannelDestroyMessage *cm)
3077 {
3078  struct CadetTunnel *t = cls;
3079  struct CadetChannel *ch;
3080 
3081  ch = lookup_channel(t,
3082  cm->ctn);
3083  if (NULL == ch)
3084  {
3085  /* We don't know about such a channel, might have been destroyed on our
3086  end in the meantime, or never existed. */
3088  "Received channel DESTORY for unknown channel %u. Ignoring.\n",
3089  ntohl(cm->ctn.cn));
3090  return;
3091  }
3093  "Received channel DESTROY on %s from %s\n",
3094  GCCH_2s(ch),
3095  GCT_2s(t));
3097  GCC_get_id(t->current_ct->cc));
3098 }
3099 
3100 
3111 static int
3113  const struct GNUNET_MessageHeader *msg)
3114 {
3115  struct CadetTunnel *t = cls;
3116 
3117  GNUNET_assert(NULL != t->current_ct);
3119  msg);
3120  return GNUNET_OK;
3121 }
3122 
3123 
3131 static void
3133  enum GNUNET_MQ_Error error)
3134 {
3135  GNUNET_break_op(0);
3136 }
3137 
3138 
3146 struct CadetTunnel *
3148 {
3149  struct CadetTunnel *t = GNUNET_new(struct CadetTunnel);
3150  struct GNUNET_MQ_MessageHandler handlers[] = {
3151  GNUNET_MQ_hd_fixed_size(plaintext_keepalive,
3153  struct GNUNET_MessageHeader,
3154  t),
3155  GNUNET_MQ_hd_var_size(plaintext_data,
3158  t),
3159  GNUNET_MQ_hd_fixed_size(plaintext_data_ack,
3162  t),
3163  GNUNET_MQ_hd_fixed_size(plaintext_channel_open,
3166  t),
3167  GNUNET_MQ_hd_fixed_size(plaintext_channel_open_ack,
3170  t),
3171  GNUNET_MQ_hd_fixed_size(plaintext_channel_destroy,
3174  t),
3176  };
3177 
3179  new_ephemeral(&t->ax);
3182  t->destination = destination;
3186  t);
3188  NULL,
3189  NULL,
3190  NULL,
3191  handlers,
3193  t);
3195  t);
3196  return t;
3197 }
3198 
3199 
3210 int
3212  const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid,
3213  struct CadetPeerPath *path)
3214 {
3215  struct CadetTConnection *ct;
3216 
3217  ct = GNUNET_new(struct CadetTConnection);
3219  ct->t = t;
3221  path,
3222  ct,
3223  cid,
3225  ct);
3226  if (NULL == ct->cc)
3227  {
3229  "%s refused inbound %s (duplicate)\n",
3230  GCT_2s(t),
3231  GCC_2s(ct->cc));
3232  GNUNET_free(ct);
3233  return GNUNET_SYSERR;
3234  }
3235  /* FIXME: schedule job to kill connection (and path?) if it takes
3236  too long to get ready! (And track performance data on how long
3237  other connections took with the tunnel!)
3238  => Note: to be done within 'connection'-logic! */
3241  ct);
3242  t->num_busy_connections++;
3244  "%s has new %s\n",
3245  GCT_2s(t),
3246  GCC_2s(ct->cc));
3247  return GNUNET_OK;
3248 }
3249 
3250 
3257 void
3260 {
3261  struct CadetTunnel *t = ct->t;
3262  uint16_t size = ntohs(msg->header.size);
3263  char cbuf [size] GNUNET_ALIGN;
3264  ssize_t decrypted_size;
3265 
3267  "%s received %u bytes of encrypted data in state %d\n",
3268  GCT_2s(t),
3269  (unsigned int)size,
3270  t->estate);
3271 
3272  switch (t->estate)
3273  {
3276  /* We did not even SEND our KX, how can the other peer
3277  send us encrypted data? Must have been that we went
3278  down and the other peer still things we are up.
3279  Let's send it KX back. */
3281  "# received encrypted without any KX",
3282  1,
3283  GNUNET_NO);
3284  if (NULL != t->kx_task)
3285  {
3287  t->kx_task = NULL;
3288  }
3289  send_kx(t,
3290  ct,
3291  &t->ax);
3292  return;
3293 
3295  /* We send KX, and other peer send KX to us at the same time.
3296  Neither KX is AUTH'ed, so let's try KX_AUTH this time. */
3298  "# received encrypted without KX_AUTH",
3299  1,
3300  GNUNET_NO);
3301  if (NULL != t->kx_task)
3302  {
3304  t->kx_task = NULL;
3305  }
3306  send_kx_auth(t,
3307  ct,
3308  &t->ax,
3309  GNUNET_YES);
3310  return;
3311 
3313  /* We did not get the KX of the other peer, but that
3314  might have been lost. Send our KX again immediately. */
3316  "# received encrypted without KX",
3317  1,
3318  GNUNET_NO);
3319  if (NULL != t->kx_task)
3320  {
3322  t->kx_task = NULL;
3323  }
3324  send_kx(t,
3325  ct,
3326  &t->ax);
3327  return;
3328 
3330  /* Great, first payload, we might graduate to OK! */
3331  case CADET_TUNNEL_KEY_OK:
3332  /* We are up and running, all good. */
3333  break;
3334  }
3335 
3336  decrypted_size = -1;
3337  if (CADET_TUNNEL_KEY_OK == t->estate)
3338  {
3339  /* We have well-established key material available,
3340  try that. (This is the common case.) */
3341  decrypted_size = t_ax_decrypt_and_validate(&t->ax,
3342  cbuf,
3343  msg,
3344  size);
3345  }
3346 
3347  if ((-1 == decrypted_size) &&
3348  (NULL != t->unverified_ax))
3349  {
3350  /* We have un-authenticated KX material available. We should try
3351  this as a back-up option, in case the sender crashed and
3352  switched keys. */
3353  decrypted_size = t_ax_decrypt_and_validate(t->unverified_ax,
3354  cbuf,
3355  msg,
3356  size);
3357  if (-1 != decrypted_size)
3358  {
3359  /* It worked! Treat this as authentication of the AX data! */
3360  cleanup_ax(&t->ax);
3361  t->ax = *t->unverified_ax;
3363  t->unverified_ax = NULL;
3364  }
3366  {
3367  /* First time it worked, move tunnel into production! */
3370  if (NULL != t->send_task)
3373  t);
3374  }
3375  }
3376  if (NULL != t->unverified_ax)
3377  {
3378  /* We had unverified KX material that was useless; so increment
3379  counter and eventually move to ignore it. Note that we even do
3380  this increment if we successfully decrypted with the old KX
3381  material and thus didn't even both with the new one. This is
3382  the ideal case, as a malicious injection of bogus KX data
3383  basically only causes us to increment a counter a few times. */
3384  t->unverified_attempts++;
3386  "Failed to decrypt message with unverified KX data %u times\n",
3387  t->unverified_attempts);
3389  {
3392  t->unverified_ax = NULL;
3393  }
3394  }
3395 
3396  if (-1 == decrypted_size)
3397  {
3398  /* Decryption failed for good, complain. */
3400  "%s failed to decrypt and validate encrypted data, retrying KX\n",
3401  GCT_2s(t));
3403  "# unable to decrypt",
3404  1,
3405  GNUNET_NO);
3406  if (NULL != t->kx_task)
3407  {
3409  t->kx_task = NULL;
3410  }
3411  send_kx(t,
3412  ct,
3413  &t->ax);
3414  return;
3415  }
3417  "# decrypted bytes",
3418  decrypted_size,
3419  GNUNET_NO);
3420 
3421  /* The MST will ultimately call #handle_decrypted() on each message. */
3422  t->current_ct = ct;
3425  cbuf,
3426  decrypted_size,
3427  GNUNET_YES,
3428  GNUNET_NO));
3429  t->current_ct = NULL;
3430 }
3431 
3432 
3443 struct CadetTunnelQueueEntry *
3445  const struct GNUNET_MessageHeader *message,
3447  void *cont_cls)
3448 {
3449  struct CadetTunnelQueueEntry *tq;
3450  uint16_t payload_size;
3451  struct GNUNET_MQ_Envelope *env;
3452  struct GNUNET_CADET_TunnelEncryptedMessage *ax_msg;
3453 
3454  if (CADET_TUNNEL_KEY_OK != t->estate)
3455  {
3456  GNUNET_break(0);
3457  return NULL;
3458  }
3459  payload_size = ntohs(message->size);
3461  "Encrypting %u bytes for %s\n",
3462  (unsigned int)payload_size,
3463  GCT_2s(t));
3464  env = GNUNET_MQ_msg_extra(ax_msg,
3465  payload_size,
3467  t_ax_encrypt(&t->ax,
3468  &ax_msg[1],
3469  message,
3470  payload_size);
3472  "# encrypted bytes",
3473  payload_size,
3474  GNUNET_NO);
3475  ax_msg->ax_header.Ns = htonl(t->ax.Ns++);
3476  ax_msg->ax_header.PNs = htonl(t->ax.PNs);
3477  /* FIXME: we should do this once, not once per message;
3478  this is a point multiplication, and DHRs does not
3479  change all the time. */
3481  &ax_msg->ax_header.DHRs);
3482  t_h_encrypt(&t->ax,
3483  ax_msg);
3484  t_hmac(&ax_msg->ax_header,
3485  sizeof(struct GNUNET_CADET_AxHeader) + payload_size,
3486  0,
3487  &t->ax.HKs,
3488  &ax_msg->hmac);
3489 
3490  tq = GNUNET_malloc(sizeof(*tq));
3491  tq->t = t;
3492  tq->env = env;
3493  tq->cid = &ax_msg->cid; /* will initialize 'ax_msg->cid' once we know the connection */
3494  tq->cont = cont;
3495  tq->cont_cls = cont_cls;
3497  t->tq_tail,
3498  tq);
3499  if (NULL != t->send_task)
3501  t->send_task
3503  t);
3504  return tq;
3505 }
3506 
3507 
3517 void
3519 {
3520  struct CadetTunnel *t = tq->t;
3521 
3523  t->tq_tail,
3524  tq);
3525  GNUNET_MQ_discard(tq->env);
3526  GNUNET_free(tq);
3527 }
3528 
3529 
3537 void
3540  void *iter_cls)
3541 {
3542  struct CadetTConnection *n;
3543 
3544  for (struct CadetTConnection *ct = t->connection_ready_head;
3545  NULL != ct;
3546  ct = n)
3547  {
3548  n = ct->next;
3549  iter(iter_cls,
3550  ct);
3551  }
3552  for (struct CadetTConnection *ct = t->connection_busy_head;
3553  NULL != ct;
3554  ct = n)
3555  {
3556  n = ct->next;
3557  iter(iter_cls,
3558  ct);
3559  }
3560 }
3561 
3562 
3566 struct ChanIterCls {
3571 
3575  void *iter_cls;
3576 };
3577 
3578 
3587 static int
3589  uint32_t key,
3590  void *value)
3591 {
3592  struct ChanIterCls *ctx = cls;
3593  struct CadetChannel *ch = value;
3594 
3595  ctx->iter(ctx->iter_cls,
3596  ch);
3597  return GNUNET_OK;
3598 }
3599 
3600 
3608 void
3610  GCT_ChannelIterator iter,
3611  void *iter_cls)
3612 {
3613  struct ChanIterCls ctx;
3614 
3615  ctx.iter = iter;
3616  ctx.iter_cls = iter_cls;
3619  &ctx);
3620 }
3621 
3622 
3631 static int
3632 debug_channel(void *cls,
3633  uint32_t key,
3634  void *value)
3635 {
3636  const enum GNUNET_ErrorType *level = cls;
3637  struct CadetChannel *ch = value;
3638 
3639  GCCH_debug(ch, *level);
3640  return GNUNET_OK;
3641 }
3642 
3643 
3644 #define LOG2(level, ...) GNUNET_log_from_nocheck(level, "cadet-tun", __VA_ARGS__)
3645 
3646 
3653 void
3654 GCT_debug(const struct CadetTunnel *t,
3655  enum GNUNET_ErrorType level)
3656 {
3657 #if !defined(GNUNET_CULL_LOGGING)
3658  struct CadetTConnection *iter_c;
3659  int do_log;
3660 
3662  "cadet-tun",
3663  __FILE__, __FUNCTION__, __LINE__);
3664  if (0 == do_log)
3665  return;
3666 
3667  LOG2(level,
3668  "TTT TUNNEL TOWARDS %s in estate %s tq_len: %u #cons: %u\n",
3669  GCT_2s(t),
3670  estate2s(t->estate),
3671  t->tq_len,
3673  LOG2(level,
3674  "TTT channels:\n");
3676  &debug_channel,
3677  &level);
3678  LOG2(level,
3679  "TTT connections:\n");
3680  for (iter_c = t->connection_ready_head; NULL != iter_c; iter_c = iter_c->next)
3681  GCC_debug(iter_c->cc,
3682  level);
3683  for (iter_c = t->connection_busy_head; NULL != iter_c; iter_c = iter_c->next)
3684  GCC_debug(iter_c->cc,
3685  level);
3686 
3687  LOG2(level,
3688  "TTT TUNNEL END\n");
3689 #endif
3690 }
3691 
3692 
3693 /* end of gnunet-service-cadet_tunnels.c */
struct CadetTunnelAxolotl ax
Axolotl info.
int GNUNET_CRYPTO_ecdhe_key_create2(struct GNUNET_CRYPTO_EcdhePrivateKey *pk)
Create a new private key.
Definition: crypto_ecc.c:632
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
Closure for evaluate_connection.
Axolotl-encrypted tunnel message with application payload.
#define GNUNET_MESSAGE_TYPE_CADET_TUNNEL_ENCRYPTED
Axolotl encrypted data.
static struct GNUNET_STATISTICS_Handle * stats
Handle for statistics.
struct CadetChannel * lookup_channel(struct CadetTunnel *t, struct GNUNET_CADET_ChannelTunnelNumber ctn)
Lookup a channel by its ctn.
Struct to old keys for skipped messages while advancing the Axolotl ratchet.
void GCT_remove_channel(struct CadetTunnel *t, struct CadetChannel *ch, struct GNUNET_CADET_ChannelTunnelNumber ctn)
Remove a channel from a tunnel.
void GCCH_handle_remote_destroy(struct CadetChannel *ch, const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti)
Destroy channel, based on the other peer closing the connection.
static struct GNUNET_CADET_Channel * ch
Channel handle.
Definition: gnunet-cadet.c:117
struct GNUNET_CONTAINER_MultiHashMap32 * channels
Channels inside this tunnel.
static void handle_plaintext_data_ack(void *cls, const struct GNUNET_CADET_ChannelDataAckMessage *ack)
We received an acknowledgement for data we sent on a channel.
void GCT_connection_lost(struct CadetTConnection *ct)
We lost a connection, remove it from our list and clean up the connection object itself.
struct GNUNET_HashCode h_port
Hash of destination port and listener.
uint32_t cn
Which number does this channel have that uniquely identfies it within its tunnel, in network byte ord...
const char * GNUNET_sh2s(const struct GNUNET_ShortHashCode *shc)
Convert a short hash value to a string (for printing debug messages).
const struct CadetConnectionMetrics * GCC_get_metrics(struct CadetConnection *cc)
Obtain performance metrics from cc.
struct CadetPeerPath * path
Path we are comparing against for evaluate_connection, can be NULL.
struct CadetTConnection * connection_ready_tail
DLL of ready connections that are actively used to reach the destination peer.
Peer description.
struct CadetPeer * GCT_get_destination(struct CadetTunnel *t)
Return the peer to which this tunnel goes.
struct GNUNET_MessageHeader * msg
Definition: 005.c:2
static const char * estate2s(enum CadetTunnelEState es)
Get string description for tunnel encryption state.
static void handle_plaintext_data(void *cls, const struct GNUNET_CADET_ChannelAppDataMessage *msg)
We received payload data for a channel.
GNUnet CADET service with encryption.
uint32_t Ns
Number of messages sent with the current ratchet key.
struct GNUNET_CADET_ChannelTunnelNumber ctn
ID of the channel.
Low-level connection to a destination.
static void t_hmac(const void *plaintext, size_t size, uint32_t iv, const struct GNUNET_CRYPTO_SymmetricSessionKey *key, struct GNUNET_ShortHashCode *hmac)
Calculate HMAC.
int duplicate
Set to GNUNET_YES if we have a connection over path already.
uint64_t rel_value_us
The actual value.
void(* GCT_SendContinuation)(void *cls, const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid)
Function called when a transmission requested using GCT_send is done.
enum CadetTunnelEState GCT_get_estate(struct CadetTunnel *t)
Get the encryption state of a tunnel.
#define GNUNET_CONTAINER_DLL_insert(head, tail, element)
Insert an element at the head of a DLL.
unsigned int max_length
Maximum length of any of our connections, 0 if we have none.
struct CadetChannel * GCCH_channel_incoming_new(struct CadetTunnel *t, struct GNUNET_CADET_ChannelTunnelNumber ctn, const struct GNUNET_HashCode *h_port, uint32_t options)
Create a new channel based on a request coming in over the network.
struct CadetTunnelSkippedKey * skipped_tail
Skipped messages&#39; keys DLL, tail.
int is_ready
Is the connection currently ready for transmission?
struct GNUNET_TIME_Absolute timestamp
When was this key stored (for timeout).
void GNUNET_CRYPTO_ecdhe_key_clear(struct GNUNET_CRYPTO_EcdhePrivateKey *pk)
Clear memory that was used to store a private key.
Definition: crypto_ecc.c:572
A connection is a live end-to-end messaging mechanism where the peers are identified by a path and kn...
struct GNUNET_CRYPTO_SymmetricSessionKey HKr
32-byte header key (currently used for receiving)
void GCCH_tunnel_up(struct CadetChannel *ch)
Function called once and only once after a channel was bound to its tunnel via GCT_add_channel() is r...
const char * GCT_2s(const struct CadetTunnel *t)
Get the static string for the peer this tunnel is directed.
unsigned long long num_successes
Number of packets that were sent via this connection did actually receive an ACK? (Note: ACKs may be ...
int GNUNET_snprintf(char *buf, size_t size, const char *format,...)
Like snprintf, just aborts if the buffer is of insufficient size.
#define DESIRED_CONNECTIONS_PER_TUNNEL
How many connections would we like to have per tunnel?
unsigned int num_ready_connections
Number of connections in the connection_ready_head DLL.
void GCT_handle_encrypted(struct CadetTConnection *ct, const struct GNUNET_CADET_TunnelEncryptedMessage *msg)
Handle encrypted message.
GNUNET_MQ_Error
Error codes for the queue.
const char * GCC_2s(const struct CadetConnection *cc)
Get a (static) string for a connection.
static int alice_or_betty(const struct GNUNET_PeerIdentity *other)
Am I Alice or Betty (some call her Bob), or talking to myself?
#define GNUNET_TIME_UNIT_MINUTES
One minute.
struct GNUNET_TIME_Absolute last_use
When was this connection last used? (by us sending or receiving a PAYLOAD message on it) ...
struct GNUNET_CADET_TunnelKeyExchangeMessage kx
Message header with key material.
struct GNUNET_PeerIdentity my_full_id
Local peer own ID.
int GNUNET_CONTAINER_multihashmap32_iterate(struct GNUNET_CONTAINER_MultiHashMap32 *map, GNUNET_CONTAINER_MulitHashMapIterator32Callback it, void *it_cls)
Iterate over all entries in the map.
uint32_t flags
Flags for the key exchange in NBO, based on enum GNUNET_CADET_KX_Flags.
struct CadetTunnel * GCT_create_tunnel(struct CadetPeer *destination)
Create a tunnel to destionation.
struct GNUNET_TIME_Absolute GNUNET_TIME_relative_to_absolute(struct GNUNET_TIME_Relative rel)
Convert relative time to an absolute time in the future.
Definition: time.c:246
struct GNUNET_MQ_Handle * mq
Dispatcher for decrypted messages only (do NOT use for sending!).
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
struct CadetTunnelQueueEntry * GCT_send(struct CadetTunnel *t, const struct GNUNET_MessageHeader *message, GCT_SendContinuation cont, void *cont_cls)
Sends an already built message on a tunnel, encrypting it and choosing the best connection if not pro...
void GCT_send_cancel(struct CadetTunnelQueueEntry *tq)
Cancel a previously sent message while it&#39;s in the queue.
const struct GNUNET_CADET_ConnectionTunnelIdentifier * GCC_get_id(struct CadetConnection *cc)
Obtain unique ID for the connection.
struct CadetTunnelQueueEntry * prev
We are entries in a DLL.
struct GNUNET_MessageHeader header
Type: GNUNET_MESSAGE_TYPE_CADET_CHANNEL_DESTROY.
struct GNUNET_TIME_Absolute ratchet_expiration
Time when the current ratchet expires and a new one is triggered (if ratchet_allowed is GNUNET_YES)...
uint32_t PNs
Previous message numbers (# of msgs sent under prev ratchet)
#define GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN_ACK
Confirm the creation of a channel.
static void mark_connection_unready(struct CadetTConnection *ct)
Connection ct is now unready, clear it&#39;s ready flag and move it from the ready DLL to the busy DLL...
void GCCH_handle_duplicate_open(struct CadetChannel *ch, const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti)
We got a GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN message again for this channel.
struct GNUNET_CRYPTO_EcdhePublicKey DHRs
Current ratchet key.
#define GNUNET_MESSAGE_TYPE_CADET_CHANNEL_DESTROY
Ask the cadet service to destroy a channel.
KX received and we sent KX_AUTH back, but we got no traffic yet, so we&#39;re waiting for either KX_AUTH ...
unsigned int GCT_count_any_connections(const struct CadetTunnel *t)
Count all created connections of a tunnel.
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
#define GNUNET_MQ_hd_fixed_size(name, code, str, ctx)
int GNUNET_CRYPTO_ecc_ecdh(const struct GNUNET_CRYPTO_EcdhePrivateKey *priv, const struct GNUNET_CRYPTO_EcdhePublicKey *pub, struct GNUNET_HashCode *key_material)
Derive key material from a public and a private ECC key.
Definition: crypto_ecc.c:1185
struct CadetTConnection * connection_ready_head
DLL of ready connections that are actively used to reach the destination peer.
#define GNUNET_MQ_msg(mvar, type)
Allocate a GNUNET_MQ_Envelope.
Definition: gnunet_mq_lib.h:67
int kx_auth_requested
Force triggering KX_AUTH independent of estate.
static void send_kx(struct CadetTunnel *t, struct CadetTConnection *ct, struct CadetTunnelAxolotl *ax)
Send a KX message.
void * iter_cls
Closure for iter.
#define GNUNET_NO
Definition: gnunet_common.h:78
void GCT_iterate_channels(struct CadetTunnel *t, GCT_ChannelIterator iter, void *iter_cls)
Iterate over all channels of a tunnel.
const char * GNUNET_h2s(const struct GNUNET_HashCode *hc)
Convert a hash value to a string (for printing debug messages).
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:75
Should the peer reply with its KX details?
Information we track per tunnel.
struct GNUNET_CRYPTO_SymmetricSessionKey NHKr
32-byte next header key (for receiving).
GNUNET_ErrorType
Types of errors.
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_add(struct GNUNET_TIME_Absolute start, struct GNUNET_TIME_Relative duration)
Add a given relative duration to the given start time.
Definition: time.c:393
uint32_t opt
Channel options.
#define GNUNET_new(type)
Allocate a struct or union of the given type.
KX message sent, waiting for other peer&#39;s KX_AUTH.
static struct CadetTConnection * get_ready_connection(struct CadetTunnel *t)
Find first connection that is ready in the list of our connections.
static void store_skipped_key(struct CadetTunnelAxolotl *ax, const struct GNUNET_CRYPTO_SymmetricSessionKey *HKr)
Delete a key from the list of skipped keys.
struct GNUNET_CADET_AxHeader ax_header
Axolotl-header that specifies which keys to use in which ratchet to decrypt the body that follows...
struct CadetConnection * GCC_create(struct CadetPeer *destination, struct CadetPeerPath *path, unsigned int off, struct CadetTConnection *ct, GCC_ReadyCallback ready_cb, void *ready_cb_cls)
Create a connection to destination via path and notify cb whenever we are ready for more data...
Encrypted axolotl header with numbers that identify which keys in which ratchet are to be used to dec...
unsigned int GCP_iterate_paths(struct CadetPeer *cp, GCP_PathIterator callback, void *callback_cls)
Iterate over the paths to a peer.
static struct GNUNET_SCHEDULER_Task * t
Main task.
uint16_t size
The length of the struct (in bytes, including the length field itself), in big-endian format...
struct CadetConnection * GCC_create_inbound(struct CadetPeer *destination, struct CadetPeerPath *path, struct CadetTConnection *ct, const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid, GCC_ReadyCallback ready_cb, void *ready_cb_cls)
Create a connection to destination via path and notify cb whenever we are ready for more data...
void GNUNET_STATISTICS_update(struct GNUNET_STATISTICS_Handle *handle, const char *name, int64_t delta, int make_persistent)
Set statistic value for the peer.
static int ret
Final status code.
Definition: gnunet-arm.c:89
static void handle_plaintext_channel_destroy(void *cls, const struct GNUNET_CADET_ChannelDestroyMessage *cm)
We received a message saying that a channel should be destroyed.
struct GNUNET_SCHEDULER_Task * destroy_task
Task scheduled if there are no more channels using the tunnel.
void GNUNET_CRYPTO_hmac(const struct GNUNET_CRYPTO_AuthKey *key, const void *plaintext, size_t plaintext_len, struct GNUNET_HashCode *hmac)
Calculate HMAC of a message (RFC 2104)
Definition: crypto_hash.c:418
int GNUNET_CONTAINER_multihashmap32_put(struct GNUNET_CONTAINER_MultiHashMap32 *map, uint32_t key, void *value, enum GNUNET_CONTAINER_MultiHashMapOption opt)
Store a key-value pair in the map.
void GCC_debug(struct CadetConnection *cc, enum GNUNET_ErrorType level)
Log connection info.
static int update_ax_by_kx(struct CadetTunnelAxolotl *ax, const struct GNUNET_PeerIdentity *pid, const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key, const struct GNUNET_CRYPTO_EcdhePublicKey *ratchet_key)
Update our Axolotl key state based on the KX data we received.
struct CadetTConnection * connection_busy_head
DLL of connections that we maintain that might be used to reach the destination peer.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur...
#define GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA
Payload data (inside an encrypted tunnel).
struct GNUNET_SCHEDULER_Task * kx_task
Task to trigger KX.
static void destroy_tunnel(void *cls)
This tunnel is no longer used, destroy it.
static struct GNUNET_DNSSTUB_Context * ctx
Context for DNS resolution.
struct CadetTunnelQueueEntry * tq_tail
Queued messages, to transmit once tunnel gets connected.
static int store_ax_keys(struct CadetTunnelAxolotl *ax, const struct GNUNET_CRYPTO_SymmetricSessionKey *HKr, uint32_t Np)
Stage skipped AX keys and calculate the message key.
A 256-bit hashcode.
GCT_ChannelIterator iter
Function to call.
const char * GCP_2s(const struct CadetPeer *cp)
Get the static string for a peer ID.
void GCT_send_channel_destroy(struct CadetTunnel *t, struct GNUNET_CADET_ChannelTunnelNumber ctn)
Send a DESTROY message via the tunnel.
static void t_ax_hmac_hash(const struct GNUNET_CRYPTO_SymmetricSessionKey *key, struct GNUNET_HashCode *hash, const void *source, unsigned int len)
Perform a HMAC.
struct GNUNET_CRYPTO_SymmetricSessionKey HK
Header key.
struct CadetTunnel * t
Tunnel this connection belongs to.
struct CadetTunnelSkippedKey * prev
DLL prev.
static void trigger_transmissions(void *cls)
Called when either we have a new connection, or a new message in the queue, or some existing connecti...
static void handle_plaintext_channel_open_ack(void *cls, const struct GNUNET_CADET_ChannelOpenAckMessage *cm)
We have received confirmation from the target peer that the given channel could be established (the p...
const char * GCPP_2s(struct CadetPeerPath *path)
Convert a path to a human-readable string.
GNUNET_CADET_KX_Flags
Flags to be used in GNUNET_CADET_KX.
static int destroy_remaining_channels(void *cls, uint32_t key, void *value)
Destroy remaining channels during shutdown.
struct GNUNET_CRYPTO_SymmetricSessionKey CKr
32-byte chain keys (used for forward-secrecy) for receiving messages.
Performance metrics for a connection.
#define GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN
Ask the cadet service to create a new channel.
#define GNUNET_MQ_msg_extra(mvar, esize, type)
Allocate an envelope, with extra space allocated after the space needed by the message struct...
Definition: gnunet_mq_lib.h:52
struct GNUNET_TIME_Relative ratchet_time
How long until we trigger a ratched advance due to time.
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_delayed(struct GNUNET_TIME_Relative delay, GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run with a specified delay.
Definition: scheduler.c:1237
uint16_t type
The type of the message (GNUNET_MESSAGE_TYPE_XXXX), in big-endian format.
static ssize_t t_ax_decrypt_and_validate(struct CadetTunnelAxolotl *ax, void *dst, const struct GNUNET_CADET_TunnelEncryptedMessage *src, size_t size)
Decrypt and verify data with the appropriate tunnel key and verify that the data has not been altered...
void(* GCT_ConnectionIterator)(void *cls, struct CadetTConnection *ct)
Iterator over connections.
double worst_score
Numeric score of worst, only set if worst is non-NULL.
enum State state
current state of profiling
Information we track per peer.
struct GNUNET_MQ_Handle * GNUNET_MQ_queue_for_callbacks(GNUNET_MQ_SendImpl send, GNUNET_MQ_DestroyImpl destroy, GNUNET_MQ_CancelImpl cancel, void *impl_state, const struct GNUNET_MQ_MessageHandler *handlers, GNUNET_MQ_ErrorHandler error_handler, void *cls)
Create a message queue for the specified handlers.
Definition: mq.c:550
static struct GNUNET_OS_Process * p
Helper process we started.
Definition: gnunet-qr.c:59
struct CadetTunnelAxolotl * unverified_ax
Unverified Axolotl info, used only if we got a fresh KX (not a KX_AUTH) while our end of the tunnel w...
int GNUNET_CONTAINER_multihashmap32_remove(struct GNUNET_CONTAINER_MultiHashMap32 *map, uint32_t key, const void *value)
Remove the given key-value pair from the map.
int GNUNET_CRYPTO_eddsa_ecdh(const struct GNUNET_CRYPTO_EddsaPrivateKey *priv, const struct GNUNET_CRYPTO_EcdhePublicKey *pub, struct GNUNET_HashCode *key_material)
Derive key material from a ECDH public key and a private EdDSA key.
Definition: crypto_ecc.c:1505
static char * value
Value of the record to add/remove.
CadetTunnelEState
All the encryption states a tunnel can be in.
GNUNET_CONTAINER_HeapCostType min_desire
Minimum desirability of any of our connections, UINT64_MAX if we have none.
void GNUNET_MST_destroy(struct GNUNET_MessageStreamTokenizer *mst)
Destroys a tokenizer.
Definition: mst.c:410
struct CadetTConnection * current_ct
Identification of the connection from which we are currently processing a message.
void * GNUNET_CONTAINER_multihashmap32_get(const struct GNUNET_CONTAINER_MultiHashMap32 *map, uint32_t key)
Given a key find a value in the map matching the key.
#define GNUNET_MQ_hd_var_size(name, code, str, ctx)
#define GNUNET_break_op(cond)
Use this for assertion violations caused by other peers (i.e.
struct GNUNET_MessageHeader header
Type: GNUNET_MESSAGE_TYPE_CADET_TUNNEL_ENCRYPTED.
void GNUNET_CRYPTO_hash(const void *block, size_t size, struct GNUNET_HashCode *ret)
Compute hash of a given block.
Definition: crypto_hash.c:44
ssize_t GNUNET_CRYPTO_symmetric_encrypt(const void *block, size_t size, const struct GNUNET_CRYPTO_SymmetricSessionKey *sessionkey, const struct GNUNET_CRYPTO_SymmetricInitializationVector *iv, void *result)
Encrypt a block using a symmetric sessionkey.
Struct containing all information regarding a channel to a remote client.
int GCT_add_inbound_connection(struct CadetTunnel *t, const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid, struct CadetPeerPath *path)
Add a connection to the tunnel.
Message for a Key eXchange for a tunnel, with authentication.
struct GNUNET_CRYPTO_EcdhePublicKey last_ephemeral
Last ephemeral public key received from the other peer, for duplicate detection.
#define GNUNET_MAX(a, b)
Definition: gnunet_common.h:82
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_now(GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run as soon as possible.
Definition: scheduler.c:1264
static void t_hmac_derive_key(const struct GNUNET_CRYPTO_SymmetricSessionKey *key, struct GNUNET_CRYPTO_SymmetricSessionKey *out, const void *source, unsigned int len)
Derive a symmetric encryption key from an HMAC-HASH.
static void delete_skipped_key(struct CadetTunnelAxolotl *ax, struct CadetTunnelSkippedKey *key)
Delete a key from the list of skipped keys.
Handle to a message stream tokenizer.
Definition: mst.c:43
#define GNUNET_MIN(a, b)
Definition: gnunet_common.h:80
#define INITIAL_KX_RETRY_DELAY
How long do we wait initially before retransmitting the KX? TODO: replace by 2 RTT if/once we have co...
void GNUNET_CRYPTO_symmetric_derive_iv(struct GNUNET_CRYPTO_SymmetricInitializationVector *iv, const struct GNUNET_CRYPTO_SymmetricSessionKey *skey, const void *salt, size_t salt_len,...)
Derive an IV.
unsigned int GNUNET_CONTAINER_multihashmap32_size(const struct GNUNET_CONTAINER_MultiHashMap32 *map)
Get the number of key-value pairs in the map.
static char buf[2048]
struct GNUNET_CADET_ConnectionTunnelIdentifier cid
ID of the connection.
unsigned int unverified_attempts
How often have we tried and failed to decrypt a message using the unverified KX material from unverif...
struct GNUNET_MessageStreamTokenizer * GNUNET_MST_create(GNUNET_MessageTokenizerCallback cb, void *cb_cls)
Create a message stream tokenizer.
Definition: mst.c:84
struct GNUNET_MessageStreamTokenizer * mst
Tokenizer for decrypted messages.
struct GNUNET_CADET_ConnectionTunnelIdentifier cid
ID of the connection.
Message for cadet data traffic.
void GCC_destroy_without_tunnel(struct CadetConnection *cc)
Destroy a connection, called if the tunnel association with the connection was already broken...
uint32_t PNs
Number of messages sent with the previous ratchet key.
int GNUNET_MST_from_buffer(struct GNUNET_MessageStreamTokenizer *mst, const char *buf, size_t size, int purge, int one_shot)
Add incoming data to the receive buffer and call the callback for all complete messages.
Definition: mst.c:113
void GNUNET_MQ_inject_message(struct GNUNET_MQ_Handle *mq, const struct GNUNET_MessageHeader *mh)
Call the message message handler that was registered for the type of the given message in the given m...
Definition: mq.c:200
void GCCH_handle_channel_plaintext_data_ack(struct CadetChannel *ch, const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti, const struct GNUNET_CADET_ChannelDataAckMessage *ack)
We got an acknowledgement for payload data for a channel.
struct GNUNET_CADET_ChannelTunnelNumber GCT_add_channel(struct CadetTunnel *t, struct CadetChannel *ch)
Add a channel to a tunnel, and notify channel that we are ready for transmission if we are already up...
Internal representation of the hash map.
void GCT_debug(const struct CadetTunnel *t, enum GNUNET_ErrorType level)
Log all possible info about the tunnel state.
static ssize_t try_old_ax_keys(struct CadetTunnelAxolotl *ax, void *dst, const struct GNUNET_CADET_TunnelEncryptedMessage *src, size_t size)
Decrypt and verify data with the appropriate tunnel key and verify that the data has not been altered...
#define GNUNET_MESSAGE_TYPE_CADET_CHANNEL_KEEPALIVE
Announce connection is still alive (direction sensitive).
Closure for iterate_channels_cb.
A 512-bit hashcode.
uint32_t reserved
For alignment.
int GNUNET_CRYPTO_ecdh_eddsa(const struct GNUNET_CRYPTO_EcdhePrivateKey *priv, const struct GNUNET_CRYPTO_EddsaPublicKey *pub, struct GNUNET_HashCode *key_material)
Derive key material from a EdDSA public key and a private ECDH key.
Definition: crypto_ecc.c:1615
Message handler for a specific message type.
struct GNUNET_CRYPTO_EcdhePublicKey ratchet_key
Sender&#39;s next ephemeral public ECC key encoded in a format suitable for network transmission, as created using &#39;gcry_sexp_sprint&#39;.
static int consider_path_cb(void *cls, struct CadetPeerPath *path, unsigned int off)
Consider using the path p for the tunnel t.
void GCT_handle_kx(struct CadetTConnection *ct, const struct GNUNET_CADET_TunnelKeyExchangeMessage *msg)
Handle KX message that lacks authentication (and which will thus only be considered authenticated aft...
static int res
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_get(void)
Get the current time.
Definition: time.c:118
struct GNUNET_CONTAINER_MultiHashMap32 * GNUNET_CONTAINER_multihashmap32_create(unsigned int len)
Create a 32-bit key multi hash map.
struct CadetConnection * cc
Connection handle.
struct GNUNET_MessageHeader header
Type: GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA.
void GNUNET_CONTAINER_multihashmap32_destroy(struct GNUNET_CONTAINER_MultiHashMap32 *map)
Destroy a 32-bit key hash map.
void GNUNET_MQ_discard(struct GNUNET_MQ_Envelope *mqm)
Discard the message queue message, free all allocated resources.
Definition: mq.c:319
#define LOG2(level,...)
static GstElement * source
Appsrc instance into which we write data for the pipeline.
struct GNUNET_CADET_ChannelTunnelNumber ctn
Number identifying this channel in its tunnel.
Private ECC key encoded for transmission.
Struct containing all information regarding a tunnel to a peer.
Message to acknowledge end-to-end data.
void GCCH_handle_channel_open_ack(struct CadetChannel *ch, const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti, const struct GNUNET_HashCode *port)
We got an acknowledgement for the creation of the channel (the port is open on the other side)...
There must only be one value per key; storing a value should fail if a value under the same key alrea...
int ratchet_allowed
True (GNUNET_YES) if we have received a message from the other peer that uses the keys from our last ...
static int iterate_channels_cb(void *cls, uint32_t key, void *value)
Helper function for GCT_iterate_channels.
struct GNUNET_HashCode key
The key used in the DHT.
int GNUNET_get_log_call_status(int caller_level, const char *comp, const char *file, const char *function, int line)
Decides whether a particular logging call should or should not be allowed to be made.
#define GNUNET_SYSERR
Definition: gnunet_common.h:76
static unsigned int size
Size of the "table".
Definition: peer.c:66
void GNUNET_CRYPTO_ecdhe_key_get_public(const struct GNUNET_CRYPTO_EcdhePrivateKey *priv, struct GNUNET_CRYPTO_EcdhePublicKey *pub)
Extract the public key for the given private key.
Definition: crypto_ecc.c:303
static void decrypted_error_cb(void *cls, enum GNUNET_MQ_Error error)
Function called if we had an error processing an incoming decrypted message.
struct GNUNET_CADET_ChannelTunnelNumber ctn
ID of the channel within the tunnel.
uint64_t GNUNET_CONTAINER_HeapCostType
Cost by which elements in a heap can be ordered.
struct GNUNET_TIME_Absolute next_kx_attempt
When do we try the next KX?
uint32_t Nr
Message number (reset to 0 with each new ratchet, next message to recv).
Message to acknowledge opening a channel of type GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN_ACK.
struct GNUNET_CADET_ChannelTunnelNumber ctn
ID of the channel.
Struct used to save messages in a non-ready tunnel to send once connected.
GNUNET_CONTAINER_HeapCostType GCPP_get_desirability(const struct CadetPeerPath *path)
Return how much we like keeping the path.
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
void GCCH_debug(struct CadetChannel *ch, enum GNUNET_ErrorType level)
Log channel info.
#define GNUNET_CONTAINER_DLL_insert_tail(head, tail, element)
Insert an element at the tail of a DLL.
void GCT_destroy_tunnel_now(struct CadetTunnel *t)
Destroys the tunnel t now, without delay.
struct CadetTunnelQueueEntry * tq_head
Queued messages, to transmit once tunnel gets connected.
#define GNUNET_TIME_STD_BACKOFF(r)
Perform our standard exponential back-off calculation, starting at 1 ms and then going by a factor of...
Handshake completed: session key available.
struct CadetPeerPath * GCC_get_path(struct CadetConnection *cc, unsigned int *off)
Obtain the path used by this connection.
Message to create a Channel.
static void evaluate_connection(void *cls, struct CadetTConnection *ct)
Evaluate a connection, updating our summary information in cls about what kinds of connections we hav...
struct CadetTunnel * t
Tunnel these messages belong in.
void GCT_consider_path(struct CadetTunnel *t, struct CadetPeerPath *p, unsigned int off)
Consider using the path p for the tunnel t.
void * cont_cls
Closure for cont.
struct GNUNET_ShortHashCode hmac
MAC of the encrypted message, used to verify message integrity.
#define GNUNET_memcmp(a, b)
Compare memory in a and b, where both must be of the same pointer type.
P2P messages used by CADET.
void GNUNET_CRYPTO_eddsa_key_get_public(const struct GNUNET_CRYPTO_EddsaPrivateKey *priv, struct GNUNET_CRYPTO_EddsaPublicKey *pub)
Extract the public key for the given private key.
Definition: crypto_ecc.c:272
struct CadetTunnelQueueEntry * next
We are entries in a DLL.
const char * GCCH_2s(const struct CadetChannel *ch)
Get the static string for identification of the channel.
int shutting_down
Signal that shutdown is happening: prevent recovery measures.
#define HIGH_BIT
Message to destroy a channel of type GNUNET_MESSAGE_TYPE_CADET_CHANNEL_DESTROY.
static int notify_tunnel_up_cb(void *cls, uint32_t key, void *value)
Our tunnel became ready for the first time, notify channels that have been waiting.
static void handle_plaintext_keepalive(void *cls, const struct GNUNET_MessageHeader *msg)
We got a keepalive.
struct GNUNET_CRYPTO_EddsaPrivateKey * my_private_key
Own private key.
struct GNUNET_MQ_Envelope * env
Envelope of message to send follows.
void GCT_handle_kx_auth(struct CadetTConnection *ct, const struct GNUNET_CADET_TunnelKeyExchangeAuthMessage *msg)
Handle KX_AUTH message.
void GCT_change_estate(struct CadetTunnel *t, enum CadetTunnelEState state)
Change the tunnel encryption state.
Handle to a message queue.
Definition: mq.c:84
struct GNUNET_CRYPTO_SymmetricSessionKey RK
32-byte root key which gets updated by DH ratchet.
void GCC_transmit(struct CadetConnection *cc, struct GNUNET_MQ_Envelope *env)
Transmit message msg via connection cc.
Private ECC key encoded for transmission.
unsigned int Kn
Key number for a given HK.
#define N
static void maintain_connections_cb(void *cls)
Function called to maintain the connections underlying our tunnel.
struct GNUNET_CRYPTO_EcdhePublicKey DHRr
ECDH Ratchet key (other peer&#39;s public key in the current DH).
Entry in list of connections used by tunnel, with metadata.
The identity of the host (wraps the signing key of the peer).
void GCP_drop_tunnel(struct CadetPeer *cp, struct CadetTunnel *t)
The tunnel to the given peer no longer exists, remove it from our data structures, and possibly clean up the peer itself.
GNUNET_CONTAINER_HeapCostType max_desire
Maximum desirability of any of our connections, 0 if we have none.
unsigned int min_length
Minimum length of any of our connections, UINT_MAX if we have none.
struct GNUNET_HashCode port
Port number of the channel, used to prove to the initiator that the receiver knows the port...
KX message sent and received, trying to send back KX_AUTH.
static int check_plaintext_data(void *cls, const struct GNUNET_CADET_ChannelAppDataMessage *msg)
Check that msg is well-formed.
#define GNUNET_ALIGN
gcc-ism to force alignment; we use this to align char-arrays that may then be cast to &#39;struct&#39;s...
struct CadetPeer * destination
Destination of the tunnel.
#define MAX_SKIPPED_KEYS
Maximum number of skipped keys we keep in memory per tunnel.
The peer should reply with its KX details?
struct GNUNET_CRYPTO_EcdhePrivateKey DHRs
ECDH Ratchet key (our private key in the current DH).
#define MAX_UNVERIFIED_ATTEMPTS
How often do we try to decrypt payload with unverified key material? Used to limit CPU increase upon ...
Hash uniquely identifying a connection below a tunnel.
Axolotl data, according to https://github.com/trevp/axolotl/wiki .
struct GNUNET_HashCode auth
KDF-proof that sender could compute the 3-DH, used in lieu of a signature or payload data...
static void connection_ready_cb(void *cls, int is_ready)
A connection is is_ready for transmission.
struct GNUNET_TIME_Relative GNUNET_TIME_absolute_get_duration(struct GNUNET_TIME_Absolute whence)
Get the duration of an operation as the difference of the current time and the given start time "henc...
Definition: time.c:373
struct CadetTunnelSkippedKey * skipped_head
A (double linked) list of stored message keys and associated header keys for "skipped" messages...
#define GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA_ACK
Confirm payload data end-to-end.
Message for a Key eXchange for a tunnel.
static void send_kx_auth(struct CadetTunnel *t, struct CadetTConnection *ct, struct CadetTunnelAxolotl *ax, int force_reply)
Send a KX_AUTH message.
Public ECC key (always for Curve25519) encoded in a format suitable for network transmission and encr...
unsigned int GCT_count_channels(struct CadetTunnel *t)
Count channels of a tunnel.
Number identifying a CADET channel within a tunnel.
Entry in list of pending tasks.
Definition: scheduler.c:131
static void handle_plaintext_channel_open(void *cls, const struct GNUNET_CADET_ChannelOpenMessage *copen)
We have received a request to open a channel to a port from another peer.
struct GNUNET_TIME_Absolute created
Creation time, to keep oldest connection alive.
static void retry_kx(void *cls)
Try to redo the KX or KX_AUTH handshake, if we can.
unsigned long long num_acked_transmissions
How many packets that ought to generate an ACK did we send via this connection?
struct GNUNET_CRYPTO_SymmetricSessionKey HKs
32-byte header key (currently used for sending).
void GCCH_handle_channel_plaintext_data(struct CadetChannel *ch, const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti, const struct GNUNET_CADET_ChannelAppDataMessage *msg)
We got payload data for a channel.
struct GNUNET_SCHEDULER_Task * maintain_connections_task
Task to trim connections if too many are present.
static int handle_decrypted(void *cls, const struct GNUNET_MessageHeader *msg)
Handles a message we decrypted, by injecting it into our message queue (which will do the dispatching...
static int debug_channel(void *cls, uint32_t key, void *value)
Call GCCH_debug() on a channel.
static void t_h_encrypt(struct CadetTunnelAxolotl *ax, struct GNUNET_CADET_TunnelEncryptedMessage *msg)
Encrypt header with the axolotl header key.
struct CadetPeer * GCPP_get_peer_at_offset(struct CadetPeerPath *path, unsigned int off)
Obtain the peer at offset off in path.
void GCT_iterate_connections(struct CadetTunnel *t, GCT_ConnectionIterator iter, void *iter_cls)
Iterate over all connections of a tunnel.
struct GNUNET_CADET_ChannelTunnelNumber ctn
ID of the channel.
static void destroy_t_connection(void *cls, struct CadetTConnection *ct)
Clean up connection ct of a tunnel.
static void cleanup_ax(struct CadetTunnelAxolotl *ax)
Cleanup state used by ax.
Uninitialized status, we need to send KX.
#define LOG(level,...)
#define GNUNET_MESSAGE_TYPE_CADET_TUNNEL_KX_AUTH
Axolotl key exchange response with authentication.
struct GNUNET_TIME_Relative GNUNET_TIME_absolute_get_remaining(struct GNUNET_TIME_Absolute future)
Given a timestamp in the future, how much time remains until then?
Definition: time.c:331
KX message received, trying to send back KX_AUTH.
static void t_h_decrypt(struct CadetTunnelAxolotl *ax, const struct GNUNET_CADET_TunnelEncryptedMessage *src, struct GNUNET_CADET_TunnelEncryptedMessage *dst)
Decrypt header with the current axolotl header key.
struct GNUNET_SCHEDULER_Task * send_task
Task to send messages from queue (if possible).
struct GNUNET_TIME_Relative kx_retry_delay
How long do we wait until we retry the KX?
Header for all communications.
struct CadetTunnelSkippedKey * next
DLL next.
Time for absolute times used by GNUnet, in microseconds.
void GNUNET_MQ_destroy(struct GNUNET_MQ_Handle *mq)
Destroy the message queue.
Definition: mq.c:821
#define GNUNET_YES
Definition: gnunet_common.h:77
static void t_ax_encrypt(struct CadetTunnelAxolotl *ax, void *dst, const void *src, size_t size)
Encrypt data with the axolotl tunnel key.
void(* GCT_ChannelIterator)(void *cls, struct CadetChannel *ch)
Iterator over channels.
#define MAX_KEY_GAP
Maximum number of keys (and thus ratchet steps) we are willing to skip before we decide this is eithe...
unsigned int ratchet_counter
Number of messages recieved since our last ratchet advance.
struct CadetTConnection * next
Next in DLL.
unsigned int tq_len
Number of entries in the tq_head DLL.
GCT_SendContinuation cont
Continuation to call once sent (on the channel layer).
struct GNUNET_CRYPTO_EcdhePublicKey ephemeral_key
Sender&#39;s ephemeral public ECC key encoded in a format suitable for network transmission, as created using &#39;gcry_sexp_sprint&#39;.
const char * GNUNET_e2s(const struct GNUNET_CRYPTO_EcdhePublicKey *p)
Convert a public key value to a string (for printing debug messages).
unsigned int num_busy_connections
Number of connections in the connection_busy_head DLL.
static struct GNUNET_PeerIdentity pid
Identity of the peer we transmit to / connect to.
struct GNUNET_CRYPTO_SymmetricSessionKey CKs
32-byte chain keys (used for forward-secrecy) for sending messages.
struct GNUNET_TIME_Absolute age
When was this connection first established? (by us sending or receiving the CREATE_ACK for the first ...
static void new_ephemeral(struct CadetTunnelAxolotl *ax)
Create a new Axolotl ephemeral (ratchet) key.
ssize_t GNUNET_CRYPTO_symmetric_decrypt(const void *block, size_t size, const struct GNUNET_CRYPTO_SymmetricSessionKey *sessionkey, const struct GNUNET_CRYPTO_SymmetricInitializationVector *iv, void *result)
Decrypt a given block using a symmetric sessionkey.
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_at(struct GNUNET_TIME_Absolute at, GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run at the specified time.
Definition: scheduler.c:1214
struct GNUNET_CADET_ChannelTunnelNumber ctn
ID of the channel.
unsigned int skipped
Number of elements in skipped_head <-> skipped_tail.
void GNUNET_CRYPTO_hmac_derive_key(struct GNUNET_CRYPTO_AuthKey *key, const struct GNUNET_CRYPTO_SymmetricSessionKey *rkey, const void *salt, size_t salt_len,...)
Derive an authentication key.
Definition: crypto_hash.c:338
Information regarding a possible path to reach a peer.
static void t_ax_decrypt(struct CadetTunnelAxolotl *ax, void *dst, const void *src, size_t size)
Decrypt data with the axolotl tunnel key.
struct CadetTConnection * connection_busy_tail
DLL of connections that we maintain that might be used to reach the destination peer.
struct GNUNET_ShortHashCode connection_of_tunnel
unsigned int GCPP_get_length(struct CadetPeerPath *path)
Return the length of the path.
int ratchet_flag
True (GNUNET_YES) if we have to send a new ratchet key in next msg.
int GNUNET_CRYPTO_kdf(void *result, size_t out_len, const void *xts, size_t xts_len, const void *skm, size_t skm_len,...)
Derive key.
Definition: crypto_kdf.c:91
enum CadetTunnelEState estate
State of the tunnel encryption.
const char * GNUNET_i2s(const struct GNUNET_PeerIdentity *pid)
Convert a peer identity to a string (for printing debug messages).
#define GNUNET_MQ_handler_end()
End-marker for the handlers array.
static void try_send_normal_payload(struct CadetTunnel *t, struct CadetTConnection *ct)
Send normal payload from queue in t via connection ct.
type for (message) authentication keys
struct GNUNET_CRYPTO_SymmetricSessionKey NHKs
32-byte next header key (for sending), used once the ratchet advances.
#define GNUNET_malloc(size)
Wrapper around malloc.
#define IDLE_DESTROY_DELAY
How long do we wait until tearing down an idle tunnel?
uint32_t Ns
Message number (reset to 0 with each new ratchet, next message to send).
#define GNUNET_MESSAGE_TYPE_CADET_TUNNEL_KX
Axolotl key exchange.
#define GNUNET_free(ptr)
Wrapper around free.
const struct GNUNET_PeerIdentity * GCP_get_id(struct CadetPeer *cp)
Obtain the peer identity for a struct CadetPeer.
Time for relative time used by GNUnet, in microseconds.
struct GNUNET_CRYPTO_EddsaPublicKey public_key
struct GNUNET_CADET_ConnectionTunnelIdentifier * cid
Where to put the connection identifier into the payload of the message in env once we have it...
uint16_t len
length of data (which is always a uint32_t, but presumably this can be used to specify that fewer byt...
struct GNUNET_CRYPTO_SymmetricSessionKey MK
Message key.
struct GNUNET_CRYPTO_EcdhePrivateKey kx_0
ECDH for key exchange (A0 / B0).
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:956
static struct GNUNET_CADET_ChannelTunnelNumber get_next_free_ctn(struct CadetTunnel *t)
Compute the next free channel tunnel number for this tunnel.
struct CadetTConnection * worst
Connection deemed the "worst" so far encountered by evaluate_connection, NULL if we did not yet encou...
Public ECC key (always for curve Ed25519) encoded in a format suitable for network transmission and E...