GNUnet  0.11.x
gnunet-service-cadet_tunnels.c
Go to the documentation of this file.
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 ( \
58  GNUNET_TIME_UNIT_SECONDS, 90)
59 
64 #define INITIAL_KX_RETRY_DELAY GNUNET_TIME_relative_multiply ( \
65  GNUNET_TIME_UNIT_MILLISECONDS, 250)
66 
70 #define MAX_SKIPPED_KEYS 64
71 
76 #define MAX_KEY_GAP 256
77 
78 
83 {
88 
93 
98 
103 
108 
112  unsigned int Kn;
113 };
114 
115 
120 {
127 
132 
137 
142 
147 
154 
161 
167 
175 
180 
185 
190 
195  struct GNUNET_CRYPTO_EcdhePublicKey last_ephemeral;
196 
201  struct GNUNET_TIME_Absolute ratchet_expiration;
202 
206  unsigned int skipped;
207 
211  uint32_t Ns;
212 
216  uint32_t Nr;
217 
221  uint32_t PNs;
222 
227 
239 
252  unsigned int ratchet_counter;
253 };
254 
255 
260 {
265 
270 
274  struct CadetTunnel *t;
275 
280 
284  void *cont_cls;
285 
290 
296 };
297 
298 
303 {
308 
313  struct GNUNET_CRYPTO_EcdhePublicKey peers_ephemeral_key;
314 
319 
324 
329 
338 
343 
348 
353 
358 
363 
368 
373 
378 
383 
388 
394 
399 
404 
409 
416 
420  struct GNUNET_TIME_Relative kx_retry_delay;
421 
425  struct GNUNET_TIME_Absolute next_kx_attempt;
426 
430  unsigned int num_ready_connections;
431 
435  unsigned int num_busy_connections;
436 
442  unsigned int unverified_attempts;
443 
447  unsigned int tq_len;
448 
452  enum CadetTunnelEState estate;
453 
458 };
459 
460 
467 int
469 {
470  if (0 > GNUNET_memcmp (&my_full_id,
471  other))
472  return GNUNET_YES;
473  else if (0 < GNUNET_memcmp (&my_full_id,
474  other))
475  return GNUNET_NO;
476  else
477  {
478  GNUNET_break_op (0);
479  return GNUNET_SYSERR;
480  }
481 }
482 
483 
490 static void
492 {
493  struct CadetTunnel *t = ct->t;
494 
498  ct);
501  ct->is_ready = GNUNET_NO;
504  ct);
506 }
507 
508 
516 const char *
517 GCT_2s (const struct CadetTunnel *t)
518 {
519  static char buf[64];
520 
521  if (NULL == t)
522  return "Tunnel(NULL)";
523  GNUNET_snprintf (buf,
524  sizeof(buf),
525  "Tunnel %s",
527  return buf;
528 }
529 
530 
538 static const char *
540 {
541  static char buf[32];
542 
543  switch (es)
544  {
546  return "CADET_TUNNEL_KEY_UNINITIALIZED";
548  return "CADET_TUNNEL_KEY_AX_RECV";
550  return "CADET_TUNNEL_KEY_AX_SENT";
552  return "CADET_TUNNEL_KEY_AX_SENT_AND_RECV";
554  return "CADET_TUNNEL_KEY_AX_AUTH_SENT";
555  case CADET_TUNNEL_KEY_OK:
556  return "CADET_TUNNEL_KEY_OK";
557  }
558  GNUNET_snprintf (buf,
559  sizeof(buf),
560  "%u (UNKNOWN STATE)",
561  es);
562  return buf;
563 }
564 
565 
572 struct CadetPeer *
574 {
575  return t->destination;
576 }
577 
578 
586 unsigned int
588 {
590 }
591 
592 
600 struct CadetChannel *
603 {
605  ntohl (ctn.cn));
606 }
607 
608 
616 unsigned int
618 {
620 }
621 
622 
630 static struct CadetTConnection *
632 {
633  struct CadetTConnection *hd = t->connection_ready_head;
634 
635  GNUNET_assert ((NULL == hd) ||
636  (GNUNET_YES == hd->is_ready));
637  return hd;
638 }
639 
640 
650 {
651  return t->estate;
652 }
653 
654 
663 static void
664 trigger_transmissions (void *cls);
665 
666 
667 /* ************************************** start core crypto ***************************** */
668 
669 
675 static void
677 {
679  "Creating new ephemeral ratchet key (DHRs)\n");
681 }
682 
683 
693 static void
694 t_hmac (const void *plaintext,
695  size_t size,
696  uint32_t iv,
698  struct GNUNET_ShortHashCode *hmac)
699 {
700  static const char ctx[] = "cadet authentication key";
701  struct GNUNET_CRYPTO_AuthKey auth_key;
702  struct GNUNET_HashCode hash;
703 
705  key,
706  &iv, sizeof(iv),
707  key, sizeof(*key),
708  ctx, sizeof(ctx),
709  NULL);
710  /* Two step: GNUNET_ShortHash is only 256 bits,
711  GNUNET_HashCode is 512, so we truncate. */
712  GNUNET_CRYPTO_hmac (&auth_key,
713  plaintext,
714  size,
715  &hash);
716  GNUNET_memcpy (hmac,
717  &hash,
718  sizeof(*hmac));
719 }
720 
721 
730 static void
732  struct GNUNET_HashCode *hash,
733  const void *source,
734  unsigned int len)
735 {
736  static const char ctx[] = "axolotl HMAC-HASH";
737  struct GNUNET_CRYPTO_AuthKey auth_key;
738 
740  key,
741  ctx, sizeof(ctx),
742  NULL);
743  GNUNET_CRYPTO_hmac (&auth_key,
744  source,
745  len,
746  hash);
747 }
748 
749 
758 static void
761  const void *source,
762  unsigned int len)
763 {
764  static const char ctx[] = "axolotl derive key";
765  struct GNUNET_HashCode h;
766 
767  t_ax_hmac_hash (key,
768  &h,
769  source,
770  len);
771  GNUNET_CRYPTO_kdf (out, sizeof(*out),
772  ctx, sizeof(ctx),
773  &h, sizeof(h),
774  NULL);
775 }
776 
777 
786 static void
788  void *dst,
789  const void *src,
790  size_t size)
791 {
794  size_t out_size;
795 
796  ax->ratchet_counter++;
797  if ((GNUNET_YES == ax->ratchet_allowed) &&
798  ((ratchet_messages <= ax->ratchet_counter) ||
801  {
802  ax->ratchet_flag = GNUNET_YES;
803  }
804  if (GNUNET_YES == ax->ratchet_flag)
805  {
806  /* Advance ratchet */
807  struct GNUNET_CRYPTO_SymmetricSessionKey keys[3];
808  struct GNUNET_HashCode dh;
809  struct GNUNET_HashCode hmac;
810  static const char ctx[] = "axolotl ratchet";
811 
812  new_ephemeral (ax);
813  ax->HKs = ax->NHKs;
814 
815  /* RK, NHKs, CKs = KDF( HMAC-HASH(RK, DH(DHRs, DHRr)) ) */
817  &ax->DHRr,
818  &dh);
819  t_ax_hmac_hash (&ax->RK,
820  &hmac,
821  &dh,
822  sizeof(dh));
823  GNUNET_CRYPTO_kdf (keys, sizeof(keys),
824  ctx, sizeof(ctx),
825  &hmac, sizeof(hmac),
826  NULL);
827  ax->RK = keys[0];
828  ax->NHKs = keys[1];
829  ax->CKs = keys[2];
830 
831  ax->PNs = ax->Ns;
832  ax->Ns = 0;
833  ax->ratchet_flag = GNUNET_NO;
835  ax->ratchet_counter = 0;
838  ratchet_time);
839  }
840 
841  t_hmac_derive_key (&ax->CKs,
842  &MK,
843  "0",
844  1);
846  &MK,
847  NULL, 0,
848  NULL);
849 
850  out_size = GNUNET_CRYPTO_symmetric_encrypt (src,
851  size,
852  &MK,
853  &iv,
854  dst);
855  GNUNET_assert (size == out_size);
856  t_hmac_derive_key (&ax->CKs,
857  &ax->CKs,
858  "1",
859  1);
860 }
861 
862 
871 static void
873  void *dst,
874  const void *src,
875  size_t size)
876 {
879  size_t out_size;
880 
881  t_hmac_derive_key (&ax->CKr,
882  &MK,
883  "0",
884  1);
886  &MK,
887  NULL, 0,
888  NULL);
889  GNUNET_assert (size >= sizeof(struct GNUNET_MessageHeader));
890  out_size = GNUNET_CRYPTO_symmetric_decrypt (src,
891  size,
892  &MK,
893  &iv,
894  dst);
895  GNUNET_assert (out_size == size);
896  t_hmac_derive_key (&ax->CKr,
897  &ax->CKr,
898  "1",
899  1);
900 }
901 
902 
909 static void
912 {
914  size_t out_size;
915 
917  &ax->HKs,
918  NULL, 0,
919  NULL);
920  out_size = GNUNET_CRYPTO_symmetric_encrypt (&msg->ax_header,
921  sizeof(struct
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);
949  out_size = GNUNET_CRYPTO_symmetric_decrypt (&src->ax_header.Ns,
950  sizeof(struct
952  &ax->HKr,
953  &iv,
954  &dst->ax_header.Ns);
955  GNUNET_assert (sizeof(struct GNUNET_CADET_AxHeader) == out_size);
956 }
957 
958 
965 static void
967  struct CadetTunnelSkippedKey *key)
968 {
970  ax->skipped_tail,
971  key);
972  GNUNET_free (key);
973  ax->skipped--;
974 }
975 
976 
987 static ssize_t
989  void *dst,
990  const struct GNUNET_CADET_TunnelEncryptedMessage *src,
991  size_t size)
992 {
993  struct CadetTunnelSkippedKey *key;
994  struct GNUNET_ShortHashCode *hmac;
996  struct GNUNET_CADET_TunnelEncryptedMessage plaintext_header;
997  struct GNUNET_CRYPTO_SymmetricSessionKey *valid_HK;
998  size_t esize;
999  size_t res;
1000  size_t len;
1001  unsigned int N;
1002 
1004  "Trying skipped keys\n");
1005  hmac = &plaintext_header.hmac;
1006  esize = size - sizeof(struct GNUNET_CADET_TunnelEncryptedMessage);
1007 
1008  /* Find a correct Header Key */
1009  valid_HK = NULL;
1010  for (key = ax->skipped_head; NULL != key; key = key->next)
1011  {
1012  t_hmac (&src->ax_header,
1013  sizeof(struct GNUNET_CADET_AxHeader) + esize,
1014  0,
1015  &key->HK,
1016  hmac);
1017  if (0 == GNUNET_memcmp (hmac,
1018  &src->hmac))
1019  {
1020  valid_HK = &key->HK;
1021  break;
1022  }
1023  }
1024  if (NULL == key)
1025  return -1;
1026 
1027  /* Should've been checked in -cadet_connection.c handle_cadet_encrypted. */
1028  GNUNET_assert (size > sizeof(struct GNUNET_CADET_TunnelEncryptedMessage));
1029  len = size - sizeof(struct GNUNET_CADET_TunnelEncryptedMessage);
1030  GNUNET_assert (len >= sizeof(struct GNUNET_MessageHeader));
1031 
1032  /* Decrypt header */
1034  &key->HK,
1035  NULL, 0,
1036  NULL);
1038  sizeof(struct GNUNET_CADET_AxHeader),
1039  &key->HK,
1040  &iv,
1041  &plaintext_header.ax_header.Ns);
1042  GNUNET_assert (sizeof(struct GNUNET_CADET_AxHeader) == res);
1043 
1044  /* Find the correct message key */
1045  N = ntohl (plaintext_header.ax_header.Ns);
1046  while ((NULL != key) &&
1047  (N != key->Kn))
1048  key = key->next;
1049  if ((NULL == key) ||
1050  (0 != GNUNET_memcmp (&key->HK,
1051  valid_HK)))
1052  return -1;
1053 
1054  /* Decrypt payload */
1056  &key->MK,
1057  NULL,
1058  0,
1059  NULL);
1060  res = GNUNET_CRYPTO_symmetric_decrypt (&src[1],
1061  len,
1062  &key->MK,
1063  &iv,
1064  dst);
1065  delete_skipped_key (ax,
1066  key);
1067  return res;
1068 }
1069 
1070 
1077 static void
1079  const struct GNUNET_CRYPTO_SymmetricSessionKey *HKr)
1080 {
1081  struct CadetTunnelSkippedKey *key;
1082 
1083  key = GNUNET_new (struct CadetTunnelSkippedKey);
1085  key->Kn = ax->Nr;
1086  key->HK = ax->HKr;
1087  t_hmac_derive_key (&ax->CKr,
1088  &key->MK,
1089  "0",
1090  1);
1091  t_hmac_derive_key (&ax->CKr,
1092  &ax->CKr,
1093  "1",
1094  1);
1096  ax->skipped_tail,
1097  key);
1098  ax->skipped++;
1099  ax->Nr++;
1100 }
1101 
1102 
1113 static int
1115  const struct GNUNET_CRYPTO_SymmetricSessionKey *HKr,
1116  uint32_t Np)
1117 {
1118  int gap;
1119 
1120  gap = Np - ax->Nr;
1122  "Storing skipped keys [%u, %u)\n",
1123  ax->Nr,
1124  Np);
1125  if (MAX_KEY_GAP < gap)
1126  {
1127  /* Avoid DoS (forcing peer to do more than #MAX_KEY_GAP HMAC operations) */
1128  /* TODO: start new key exchange on return */
1129  GNUNET_break_op (0);
1131  "Got message %u, expected %u+\n",
1132  Np,
1133  ax->Nr);
1134  return GNUNET_SYSERR;
1135  }
1136  if (0 > gap)
1137  {
1138  /* Delayed message: don't store keys, flag to try old keys. */
1139  return GNUNET_SYSERR;
1140  }
1141 
1142  while (ax->Nr < Np)
1143  store_skipped_key (ax,
1144  HKr);
1145 
1146  while (ax->skipped > MAX_SKIPPED_KEYS)
1147  delete_skipped_key (ax,
1148  ax->skipped_tail);
1149  return GNUNET_OK;
1150 }
1151 
1152 
1163 static ssize_t
1165  void *dst,
1166  const struct
1168  size_t size)
1169 {
1170  struct GNUNET_ShortHashCode msg_hmac;
1171  struct GNUNET_HashCode hmac;
1172  struct GNUNET_CADET_TunnelEncryptedMessage plaintext_header;
1173  uint32_t Np;
1174  uint32_t PNp;
1175  size_t esize; /* Size of encryped payload */
1176 
1177  esize = size - sizeof(struct GNUNET_CADET_TunnelEncryptedMessage);
1178 
1179  /* Try current HK */
1180  t_hmac (&src->ax_header,
1181  sizeof(struct GNUNET_CADET_AxHeader) + esize,
1182  0, &ax->HKr,
1183  &msg_hmac);
1184  if (0 != GNUNET_memcmp (&msg_hmac,
1185  &src->hmac))
1186  {
1187  static const char ctx[] = "axolotl ratchet";
1188  struct GNUNET_CRYPTO_SymmetricSessionKey keys[3]; /* RKp, NHKp, CKp */
1190  struct GNUNET_HashCode dh;
1191  struct GNUNET_CRYPTO_EcdhePublicKey *DHRp;
1192 
1193  /* Try Next HK */
1194  t_hmac (&src->ax_header,
1195  sizeof(struct GNUNET_CADET_AxHeader) + esize,
1196  0,
1197  &ax->NHKr,
1198  &msg_hmac);
1199  if (0 != GNUNET_memcmp (&msg_hmac,
1200  &src->hmac))
1201  {
1202  /* Try the skipped keys, if that fails, we're out of luck. */
1203  return try_old_ax_keys (ax,
1204  dst,
1205  src,
1206  size);
1207  }
1208  HK = ax->HKr;
1209  ax->HKr = ax->NHKr;
1210  t_h_decrypt (ax,
1211  src,
1212  &plaintext_header);
1213  Np = ntohl (plaintext_header.ax_header.Ns);
1214  PNp = ntohl (plaintext_header.ax_header.PNs);
1215  DHRp = &plaintext_header.ax_header.DHRs;
1216  store_ax_keys (ax,
1217  &HK,
1218  PNp);
1219 
1220  /* RKp, NHKp, CKp = KDF (HMAC-HASH (RK, DH (DHRp, DHRs))) */
1222  DHRp,
1223  &dh);
1224  t_ax_hmac_hash (&ax->RK,
1225  &hmac,
1226  &dh, sizeof(dh));
1227  GNUNET_CRYPTO_kdf (keys, sizeof(keys),
1228  ctx, sizeof(ctx),
1229  &hmac, sizeof(hmac),
1230  NULL);
1231 
1232  /* Commit "purported" keys */
1233  ax->RK = keys[0];
1234  ax->NHKr = keys[1];
1235  ax->CKr = keys[2];
1236  ax->DHRr = *DHRp;
1237  ax->Nr = 0;
1239  }
1240  else
1241  {
1242  t_h_decrypt (ax,
1243  src,
1244  &plaintext_header);
1245  Np = ntohl (plaintext_header.ax_header.Ns);
1246  PNp = ntohl (plaintext_header.ax_header.PNs);
1247  }
1248  if ((Np != ax->Nr) &&
1249  (GNUNET_OK != store_ax_keys (ax,
1250  &ax->HKr,
1251  Np)))
1252  {
1253  /* Try the skipped keys, if that fails, we're out of luck. */
1254  return try_old_ax_keys (ax,
1255  dst,
1256  src,
1257  size);
1258  }
1259 
1260  t_ax_decrypt (ax,
1261  dst,
1262  &src[1],
1263  esize);
1264  ax->Nr = Np + 1;
1265  return esize;
1266 }
1267 
1268 
1278 static int
1280  uint32_t key,
1281  void *value)
1282 {
1283  struct CadetChannel *ch = value;
1284 
1285  GCCH_tunnel_up (ch);
1286  return GNUNET_OK;
1287 }
1288 
1289 
1297 void
1299  enum CadetTunnelEState state)
1300 {
1301  enum CadetTunnelEState old = t->estate;
1302 
1303  t->estate = state;
1305  "%s estate changed from %s to %s\n",
1306  GCT_2s (t),
1307  estate2s (old),
1308  estate2s (state));
1309 
1310  if ((CADET_TUNNEL_KEY_OK != old) &&
1311  (CADET_TUNNEL_KEY_OK == t->estate))
1312  {
1313  if (NULL != t->kx_task)
1314  {
1316  t->kx_task = NULL;
1317  }
1318  /* notify all channels that have been waiting */
1321  t);
1322  if (NULL != t->send_task)
1325  t);
1326  }
1327 }
1328 
1329 
1338 static void
1340  struct CadetTConnection *ct,
1341  struct CadetTunnelAxolotl *ax)
1342 {
1343  struct CadetConnection *cc;
1344  struct GNUNET_MQ_Envelope *env;
1347 
1349  return; /* only Alice may send KX */
1350  if ((NULL == ct) ||
1351  (GNUNET_NO == ct->is_ready))
1352  ct = get_ready_connection (t);
1353  if (NULL == ct)
1354  {
1356  "Wanted to send %s in state %s, but no connection is ready, deferring\n",
1357  GCT_2s (t),
1358  estate2s (t->estate));
1360  return;
1361  }
1362  cc = ct->cc;
1363  env = GNUNET_MQ_msg (msg,
1365  flags = GNUNET_CADET_KX_FLAG_FORCE_REPLY; /* always for KX */
1366  msg->flags = htonl (flags);
1367  msg->cid = *GCC_get_id (cc);
1369  &msg->ephemeral_key);
1370 #if DEBUG_KX
1371  msg->ephemeral_key_XXX = ax->kx_0;
1372  msg->private_key_XXX = *my_private_key;
1373 #endif
1375  "Sending KX message to %s with ephemeral %s on CID %s\n",
1376  GCT_2s (t),
1377  GNUNET_e2s (&msg->ephemeral_key),
1380  &msg->ratchet_key);
1385  GCT_change_estate (t,
1387  else if (CADET_TUNNEL_KEY_AX_RECV == t->estate)
1388  GCT_change_estate (t,
1390  GCC_transmit (cc,
1391  env);
1393  "# KX transmitted",
1394  1,
1395  GNUNET_NO);
1396 }
1397 
1398 
1409 static void
1411  struct CadetTConnection *ct,
1412  struct CadetTunnelAxolotl *ax,
1413  int force_reply)
1414 {
1415  struct CadetConnection *cc;
1416  struct GNUNET_MQ_Envelope *env;
1418  enum GNUNET_CADET_KX_Flags flags;
1419 
1420  if ((NULL == ct) ||
1421  (GNUNET_NO == ct->is_ready))
1422  ct = get_ready_connection (t);
1423  if (NULL == ct)
1424  {
1426  "Wanted to send KX_AUTH on %s, but no connection is ready, deferring\n",
1427  GCT_2s (t));
1429  t->kx_auth_requested = GNUNET_YES; /* queue KX_AUTH independent of estate */
1430  return;
1431  }
1432  t->kx_auth_requested = GNUNET_NO; /* clear flag */
1433  cc = ct->cc;
1434  env = GNUNET_MQ_msg (msg,
1436  flags = GNUNET_CADET_KX_FLAG_NONE;
1437  if (GNUNET_YES == force_reply)
1439  msg->kx.flags = htonl (flags);
1440  msg->kx.cid = *GCC_get_id (cc);
1442  &msg->kx.ephemeral_key);
1444  &msg->kx.ratchet_key);
1445 #if DEBUG_KX
1446  msg->kx.ephemeral_key_XXX = ax->kx_0;
1447  msg->kx.private_key_XXX = *my_private_key;
1448  msg->r_ephemeral_key_XXX = ax->last_ephemeral;
1449 #endif
1451  "Sending KX_AUTH message to %s with ephemeral %s on CID %s\n",
1452  GCT_2s (t),
1453  GNUNET_e2s (&msg->kx.ephemeral_key),
1455 
1456  /* Compute authenticator (this is the main difference to #send_kx()) */
1457  GNUNET_CRYPTO_hash (&ax->RK,
1458  sizeof(ax->RK),
1459  &msg->auth);
1460  /* Compute when to be triggered again; actual job will
1461  be scheduled via #connection_ready_cb() */
1462  t->kx_retry_delay
1464  t->next_kx_attempt
1466 
1467  /* Send via cc, mark it as unready */
1469 
1470  /* Update state machine, unless we are already OK */
1471  if (CADET_TUNNEL_KEY_OK != t->estate)
1472  GCT_change_estate (t,
1474  GCC_transmit (cc,
1475  env);
1477  "# KX_AUTH transmitted",
1478  1,
1479  GNUNET_NO);
1480 }
1481 
1482 
1488 static void
1490 {
1491  while (NULL != ax->skipped_head)
1492  delete_skipped_key (ax,
1493  ax->skipped_head);
1494  GNUNET_assert (0 == ax->skipped);
1497 }
1498 
1499 
1513 static int
1515  const struct GNUNET_PeerIdentity *pid,
1516  const struct GNUNET_CRYPTO_EcdhePublicKey *ephemeral_key,
1517  const struct GNUNET_CRYPTO_EcdhePublicKey *ratchet_key)
1518 {
1519  struct GNUNET_HashCode key_material[3];
1520  struct GNUNET_CRYPTO_SymmetricSessionKey keys[5];
1521  const char salt[] = "CADET Axolotl salt";
1522  int am_I_alice;
1523 
1524  if (GNUNET_SYSERR == (am_I_alice = GCT_alice_or_betty (pid)))
1525  {
1526  GNUNET_break_op (0);
1527  return GNUNET_SYSERR;
1528  }
1529  if (0 == GNUNET_memcmp (&ax->DHRr,
1530  ratchet_key))
1531  {
1533  "# Ratchet key already known",
1534  1,
1535  GNUNET_NO);
1537  "Ratchet key already known. Ignoring KX.\n");
1538  return GNUNET_NO;
1539  }
1540 
1541  ax->DHRr = *ratchet_key;
1542  ax->last_ephemeral = *ephemeral_key;
1543  /* ECDH A B0 */
1544  if (GNUNET_YES == am_I_alice)
1545  {
1547  ephemeral_key, /* B0 */
1548  &key_material[0]);
1549  }
1550  else
1551  {
1552  GNUNET_CRYPTO_ecdh_eddsa (&ax->kx_0, /* b0 */
1553  &pid->public_key, /* A */
1554  &key_material[0]);
1555  }
1556  /* ECDH A0 B */
1557  if (GNUNET_YES == am_I_alice)
1558  {
1559  GNUNET_CRYPTO_ecdh_eddsa (&ax->kx_0, /* a0 */
1560  &pid->public_key, /* B */
1561  &key_material[1]);
1562  }
1563  else
1564  {
1566  ephemeral_key, /* A0 */
1567  &key_material[1]);
1568  }
1569 
1570  /* ECDH A0 B0 */
1571  GNUNET_CRYPTO_ecc_ecdh (&ax->kx_0, /* a0 or b0 */
1572  ephemeral_key, /* B0 or A0 */
1573  &key_material[2]);
1574  /* KDF */
1575  GNUNET_CRYPTO_kdf (keys, sizeof(keys),
1576  salt, sizeof(salt),
1577  &key_material, sizeof(key_material),
1578  NULL);
1579 
1580  if (0 == memcmp (&ax->RK,
1581  &keys[0],
1582  sizeof(ax->RK)))
1583  {
1585  "Root key already known. Ignoring KX.\n");
1587  "# Root key already known",
1588  1,
1589  GNUNET_NO);
1590  return GNUNET_NO;
1591  }
1592 
1593  ax->RK = keys[0];
1594  if (GNUNET_YES == am_I_alice)
1595  {
1596  ax->HKr = keys[1];
1597  ax->NHKs = keys[2];
1598  ax->NHKr = keys[3];
1599  ax->CKr = keys[4];
1600  ax->ratchet_flag = GNUNET_YES;
1601  }
1602  else
1603  {
1604  ax->HKs = keys[1];
1605  ax->NHKr = keys[2];
1606  ax->NHKs = keys[3];
1607  ax->CKs = keys[4];
1608  ax->ratchet_flag = GNUNET_NO;
1609  ax->ratchet_expiration
1611  ratchet_time);
1612  }
1613  return GNUNET_OK;
1614 }
1615 
1616 
1622 static void
1623 retry_kx (void *cls)
1624 {
1625  struct CadetTunnel *t = cls;
1626  struct CadetTunnelAxolotl *ax;
1627 
1628  t->kx_task = NULL;
1630  "Trying to make KX progress on %s in state %s\n",
1631  GCT_2s (t),
1632  estate2s (t->estate));
1633  switch (t->estate)
1634  {
1635  case CADET_TUNNEL_KEY_UNINITIALIZED: /* first attempt */
1636  case CADET_TUNNEL_KEY_AX_SENT: /* trying again */
1637  send_kx (t,
1638  NULL,
1639  &t->ax);
1640  break;
1641 
1644  /* We are responding, so only require reply
1645  if WE have a channel waiting. */
1646  if (NULL != t->unverified_ax)
1647  {
1648  /* Send AX_AUTH so we might get this one verified */
1649  ax = t->unverified_ax;
1650  }
1651  else
1652  {
1653  /* How can this be? */
1654  GNUNET_break (0);
1655  ax = &t->ax;
1656  }
1657  send_kx_auth (t,
1658  NULL,
1659  ax,
1660  (0 == GCT_count_channels (t))
1661  ? GNUNET_NO
1662  : GNUNET_YES);
1663  break;
1664 
1666  /* We are responding, so only require reply
1667  if WE have a channel waiting. */
1668  if (NULL != t->unverified_ax)
1669  {
1670  /* Send AX_AUTH so we might get this one verified */
1671  ax = t->unverified_ax;
1672  }
1673  else
1674  {
1675  /* How can this be? */
1676  GNUNET_break (0);
1677  ax = &t->ax;
1678  }
1679  send_kx_auth (t,
1680  NULL,
1681  ax,
1682  (0 == GCT_count_channels (t))
1683  ? GNUNET_NO
1684  : GNUNET_YES);
1685  break;
1686 
1687  case CADET_TUNNEL_KEY_OK:
1688  /* Must have been the *other* peer asking us to
1689  respond with a KX_AUTH. */
1690  if (NULL != t->unverified_ax)
1691  {
1692  /* Sending AX_AUTH in response to AX so we might get this one verified */
1693  ax = t->unverified_ax;
1694  }
1695  else
1696  {
1697  /* Sending AX_AUTH in response to AX_AUTH */
1698  ax = &t->ax;
1699  }
1700  send_kx_auth (t,
1701  NULL,
1702  ax,
1703  GNUNET_NO);
1704  break;
1705  }
1706 }
1707 
1708 
1717 void
1720 {
1721  struct CadetTunnel *t = ct->t;
1722  int ret;
1723 
1725  "# KX received",
1726  1,
1727  GNUNET_NO);
1728  if (GNUNET_YES ==
1730  {
1731  /* Betty/Bob is not allowed to send KX! */
1732  GNUNET_break_op (0);
1733  return;
1734  }
1736  "Received KX message from %s with ephemeral %s from %s on connection %s\n",
1737  GCT_2s (t),
1738  GNUNET_e2s (&msg->ephemeral_key),
1740  GCC_2s (ct->cc));
1741 #if 1
1742  if ((0 ==
1743  memcmp (&t->ax.DHRr,
1744  &msg->ratchet_key,
1745  sizeof(msg->ratchet_key))) &&
1746  (0 ==
1747  memcmp (&t->ax.last_ephemeral,
1748  &msg->ephemeral_key,
1749  sizeof(msg->ephemeral_key))))
1750 
1751  {
1753  "# Duplicate KX received",
1754  1,
1755  GNUNET_NO);
1756  send_kx_auth (t,
1757  ct,
1758  &t->ax,
1759  GNUNET_NO);
1760  return;
1761  }
1762 #endif
1763  /* We only keep ONE unverified KX around, so if there is an existing one,
1764  clean it up. */
1765  if (NULL != t->unverified_ax)
1766  {
1767  if ((0 ==
1768  memcmp (&t->unverified_ax->DHRr,
1769  &msg->ratchet_key,
1770  sizeof(msg->ratchet_key))) &&
1771  (0 ==
1772  memcmp (&t->unverified_ax->last_ephemeral,
1773  &msg->ephemeral_key,
1774  sizeof(msg->ephemeral_key))))
1775  {
1777  "# Duplicate unverified KX received",
1778  1,
1779  GNUNET_NO);
1780 #if 1
1781  send_kx_auth (t,
1782  ct,
1783  t->unverified_ax,
1784  GNUNET_NO);
1785  return;
1786 #endif
1787  }
1789  "Dropping old unverified KX state.\n");
1791  "# Unverified KX dropped for fresh KX",
1792  1,
1793  GNUNET_NO);
1794  GNUNET_break (NULL == t->unverified_ax->skipped_head);
1795  memset (t->unverified_ax,
1796  0,
1797  sizeof(struct CadetTunnelAxolotl));
1798  }
1799  else
1800  {
1802  "Creating fresh unverified KX for %s\n",
1803  GCT_2s (t));
1805  "# Fresh KX setup",
1806  1,
1807  GNUNET_NO);
1809  }
1810  /* Set as the 'current' RK/DHRr the one we are currently using,
1811  so that the duplicate-detection logic of
1812  #update_ax_by_kx can work. */
1813  t->unverified_ax->RK = t->ax.RK;
1814  t->unverified_ax->DHRr = t->ax.DHRr;
1815  t->unverified_ax->DHRs = t->ax.DHRs;
1816  t->unverified_ax->kx_0 = t->ax.kx_0;
1817  t->unverified_attempts = 0;
1818 
1819  /* Update 'ax' by the new key material */
1820  ret = update_ax_by_kx (t->unverified_ax,
1821  GCP_get_id (t->destination),
1822  &msg->ephemeral_key,
1823  &msg->ratchet_key);
1824  GNUNET_break (GNUNET_SYSERR != ret);
1825  if (GNUNET_OK != ret)
1826  {
1828  "# Useless KX",
1829  1,
1830  GNUNET_NO);
1831  return; /* duplicate KX, nothing to do */
1832  }
1833  /* move ahead in our state machine */
1835  GCT_change_estate (t,
1837  else if (CADET_TUNNEL_KEY_AX_SENT == t->estate)
1838  GCT_change_estate (t,
1840 
1841  /* KX is still not done, try again our end. */
1842  if (CADET_TUNNEL_KEY_OK != t->estate)
1843  {
1844  if (NULL != t->kx_task)
1846  t->kx_task
1848  t);
1849  }
1850 }
1851 
1852 
1853 #if DEBUG_KX
1854 static void
1855 check_ee (const struct GNUNET_CRYPTO_EcdhePrivateKey *e1,
1856  const struct GNUNET_CRYPTO_EcdhePrivateKey *e2)
1857 {
1858  struct GNUNET_CRYPTO_EcdhePublicKey p1;
1859  struct GNUNET_CRYPTO_EcdhePublicKey p2;
1860  struct GNUNET_HashCode hc1;
1861  struct GNUNET_HashCode hc2;
1862 
1864  &p1);
1866  &p2);
1869  &p2,
1870  &hc1));
1873  &p1,
1874  &hc2));
1875  GNUNET_break (0 == GNUNET_memcmp (&hc1,
1876  &hc2));
1877 }
1878 
1879 
1880 static void
1881 check_ed (const struct GNUNET_CRYPTO_EcdhePrivateKey *e1,
1882  const struct GNUNET_CRYPTO_EddsaPrivateKey *e2)
1883 {
1884  struct GNUNET_CRYPTO_EcdhePublicKey p1;
1885  struct GNUNET_CRYPTO_EddsaPublicKey p2;
1886  struct GNUNET_HashCode hc1;
1887  struct GNUNET_HashCode hc2;
1888 
1890  &p1);
1892  &p2);
1895  &p2,
1896  &hc1));
1899  &p1,
1900  &hc2));
1901  GNUNET_break (0 == GNUNET_memcmp (&hc1,
1902  &hc2));
1903 }
1904 
1905 
1906 static void
1907 test_crypto_bug (const struct GNUNET_CRYPTO_EcdhePrivateKey *e1,
1908  const struct GNUNET_CRYPTO_EcdhePrivateKey *e2,
1909  const struct GNUNET_CRYPTO_EddsaPrivateKey *d1,
1910  const struct GNUNET_CRYPTO_EddsaPrivateKey *d2)
1911 {
1912  check_ee (e1, e2);
1913  check_ed (e1, d2);
1914  check_ed (e2, d1);
1915 }
1916 
1917 
1918 #endif
1919 
1920 
1927 void
1930 {
1931  struct CadetTunnel *t = ct->t;
1932  struct CadetTunnelAxolotl ax_tmp;
1933  struct GNUNET_HashCode kx_auth;
1934  int ret;
1935 
1937  "# KX_AUTH received",
1938  1,
1939  GNUNET_NO);
1940  if ((CADET_TUNNEL_KEY_UNINITIALIZED == t->estate) ||
1942  {
1943  /* Confusing, we got a KX_AUTH before we even send our own
1944  KX. This should not happen. We'll send our own KX ASAP anyway,
1945  so let's ignore this here. */
1946  GNUNET_break_op (0);
1947  return;
1948  }
1950  "Handling KX_AUTH message from %s with ephemeral %s\n",
1951  GCT_2s (t),
1952  GNUNET_e2s (&msg->kx.ephemeral_key));
1953  /* We do everything in ax_tmp until we've checked the authentication
1954  so we don't clobber anything we care about by accident. */
1955  ax_tmp = t->ax;
1956 
1957  /* Update 'ax' by the new key material */
1958  ret = update_ax_by_kx (&ax_tmp,
1959  GCP_get_id (t->destination),
1960  &msg->kx.ephemeral_key,
1961  &msg->kx.ratchet_key);
1962  if (GNUNET_OK != ret)
1963  {
1964  if (GNUNET_NO == ret)
1966  "# redundant KX_AUTH received",
1967  1,
1968  GNUNET_NO);
1969  else
1970  GNUNET_break (0); /* connect to self!? */
1971  return;
1972  }
1973  GNUNET_CRYPTO_hash (&ax_tmp.RK,
1974  sizeof(ax_tmp.RK),
1975  &kx_auth);
1976  if (0 != GNUNET_memcmp (&kx_auth,
1977  &msg->auth))
1978  {
1979  /* This KX_AUTH is not using the latest KX/KX_AUTH data
1980  we transmitted to the sender, refuse it, try KX again. */
1982  "# KX_AUTH not using our last KX received (auth failure)",
1983  1,
1984  GNUNET_NO);
1986  "KX AUTH mismatch!\n");
1987 #if DEBUG_KX
1988  {
1989  struct GNUNET_CRYPTO_EcdhePublicKey ephemeral_key;
1990 
1992  &ephemeral_key);
1993  if (0 != GNUNET_memcmp (&ephemeral_key,
1994  &msg->r_ephemeral_key_XXX))
1995  {
1997  "My ephemeral is %s!\n",
1998  GNUNET_e2s (&ephemeral_key));
2000  "Response is for ephemeral %s!\n",
2001  GNUNET_e2s (&msg->r_ephemeral_key_XXX));
2002  }
2003  else
2004  {
2005  test_crypto_bug (&ax_tmp.kx_0,
2006  &msg->kx.ephemeral_key_XXX,
2008  &msg->kx.private_key_XXX);
2009  }
2010  }
2011 #endif
2012  if (NULL == t->kx_task)
2013  t->kx_task
2015  &retry_kx,
2016  t);
2017  return;
2018  }
2019  /* Yep, we're good. */
2020  t->ax = ax_tmp;
2021  if (NULL != t->unverified_ax)
2022  {
2023  /* We got some "stale" KX before, drop that. */
2026  t->unverified_ax = NULL;
2027  }
2028 
2029  /* move ahead in our state machine */
2030  switch (t->estate)
2031  {
2034  /* Checked above, this is impossible. */
2035  GNUNET_assert (0);
2036  break;
2037 
2038  case CADET_TUNNEL_KEY_AX_SENT: /* This is the normal case */
2039  case CADET_TUNNEL_KEY_AX_SENT_AND_RECV: /* both peers started KX */
2040  case CADET_TUNNEL_KEY_AX_AUTH_SENT: /* both peers now did KX_AUTH */
2041  GCT_change_estate (t,
2043  break;
2044 
2045  case CADET_TUNNEL_KEY_OK:
2046  /* Did not expect another KX_AUTH, but so what, still acceptable.
2047  Nothing to do here. */
2048  break;
2049  }
2050  if (0 != (GNUNET_CADET_KX_FLAG_FORCE_REPLY & ntohl (msg->kx.flags)))
2051  {
2052  send_kx_auth (t,
2053  NULL,
2054  &t->ax,
2055  GNUNET_NO);
2056  }
2057 }
2058 
2059 
2060 /* ************************************** end core crypto ***************************** */
2061 
2062 
2071 {
2072 #define HIGH_BIT 0x8000000
2074  uint32_t ctn;
2075  int cmp;
2076  uint32_t highbit;
2077 
2078  cmp = GNUNET_memcmp (&my_full_id,
2080  if (0 < cmp)
2081  highbit = HIGH_BIT;
2082  else if (0 > cmp)
2083  highbit = 0;
2084  else
2085  GNUNET_assert (0); // loopback must never go here!
2086  ctn = ntohl (t->next_ctn.cn);
2087  while (NULL !=
2089  ctn | highbit))
2090  {
2091  ctn = ((ctn + 1) & (~HIGH_BIT));
2092  }
2093  t->next_ctn.cn = htonl ((ctn + 1) & (~HIGH_BIT));
2094  ret.cn = htonl (ctn | highbit);
2095  return ret;
2096 }
2097 
2098 
2110  struct CadetChannel *ch)
2111 {
2113 
2114  ctn = get_next_free_ctn (t);
2115  if (NULL != t->destroy_task)
2116  {
2117  GNUNET_SCHEDULER_cancel (t->destroy_task);
2118  t->destroy_task = NULL;
2119  }
2122  ntohl (ctn.cn),
2123  ch,
2126  "Adding %s to %s with state %d\n",
2127  GCCH_2s (ch),
2128  GCT_2s (t),
2129  t->estate);
2130  switch (t->estate)
2131  {
2133  /* waiting for connection to start KX */
2134  break;
2135 
2139  /* we're currently waiting for KX to complete */
2140  break;
2141 
2143  /* waiting for OTHER peer to send us data,
2144  we might need to prompt more aggressively! */
2145  if (NULL == t->kx_task)
2146  t->kx_task
2147  = GNUNET_SCHEDULER_add_at (t->next_kx_attempt,
2148  &retry_kx,
2149  t);
2150  break;
2151 
2152  case CADET_TUNNEL_KEY_OK:
2153  /* We are ready. Tell the new channel that we are up. */
2154  GCCH_tunnel_up (ch);
2155  break;
2156  }
2157  return ctn;
2158 }
2159 
2160 
2167 void
2169 {
2170  struct CadetTunnel *t = ct->t;
2171 
2172  if (GNUNET_YES == ct->is_ready)
2173  {
2176  ct);
2177  t->num_ready_connections--;
2178  }
2179  else
2180  {
2183  ct);
2184  t->num_busy_connections--;
2185  }
2186  GNUNET_free (ct);
2187 }
2188 
2189 
2196 static void
2198  struct CadetTConnection *ct)
2199 {
2200  struct CadetTunnel *t = cls;
2201  struct CadetConnection *cc = ct->cc;
2202 
2203  GNUNET_assert (ct->t == t);
2204  GCT_connection_lost (ct);
2206 }
2207 
2208 
2214 static void
2215 destroy_tunnel (void *cls)
2216 {
2217  struct CadetTunnel *t = cls;
2218  struct CadetTunnelQueueEntry *tq;
2219 
2220  t->destroy_task = NULL;
2222  "Destroying idle %s\n",
2223  GCT_2s (t));
2224  GNUNET_assert (0 == GCT_count_channels (t));
2227  t);
2228  GNUNET_assert (NULL == t->connection_ready_head);
2229  GNUNET_assert (NULL == t->connection_busy_head);
2230  while (NULL != (tq = t->tq_head))
2231  {
2232  if (NULL != tq->cont)
2233  tq->cont (tq->cont_cls,
2234  NULL);
2235  GCT_send_cancel (tq);
2236  }
2238  t);
2240  if (NULL != t->maintain_connections_task)
2241  {
2243  t->maintain_connections_task = NULL;
2244  }
2245  if (NULL != t->send_task)
2246  {
2248  t->send_task = NULL;
2249  }
2250  if (NULL != t->kx_task)
2251  {
2253  t->kx_task = NULL;
2254  }
2255  GNUNET_MST_destroy (t->mst);
2256  GNUNET_MQ_destroy (t->mq);
2257  if (NULL != t->unverified_ax)
2258  {
2261  }
2262  cleanup_ax (&t->ax);
2263  GNUNET_assert (NULL == t->destroy_task);
2264  GNUNET_free (t);
2265 }
2266 
2267 
2275 void
2277  struct CadetChannel *ch,
2279 {
2281  "Removing %s from %s\n",
2282  GCCH_2s (ch),
2283  GCT_2s (t));
2286  ntohl (ctn.cn),
2287  ch));
2288  if ((0 ==
2289  GCT_count_channels (t)) &&
2290  (NULL == t->destroy_task))
2291  {
2292  t->destroy_task
2294  &destroy_tunnel,
2295  t);
2296  }
2297 }
2298 
2299 
2308 static int
2310  uint32_t key,
2311  void *value)
2312 {
2313  struct CadetChannel *ch = value;
2314 
2316  NULL);
2317  return GNUNET_OK;
2318 }
2319 
2320 
2326 void
2328 {
2332  t);
2333  GNUNET_assert (0 ==
2334  GCT_count_channels (t));
2335  if (NULL != t->destroy_task)
2336  {
2338  t->destroy_task = NULL;
2339  }
2340  destroy_tunnel (t);
2341 }
2342 
2343 
2351 static void
2353  struct CadetTConnection *ct)
2354 {
2355  struct CadetTunnelQueueEntry *tq;
2356 
2358  tq = t->tq_head;
2359  if (NULL == tq)
2360  {
2361  /* no messages pending right now */
2363  "Not sending payload of %s on ready %s (nothing pending)\n",
2364  GCT_2s (t),
2365  GCC_2s (ct->cc));
2366  return;
2367  }
2368  /* ready to send message 'tq' on tunnel 'ct' */
2369  GNUNET_assert (t == tq->t);
2371  t->tq_tail,
2372  tq);
2373  if (NULL != tq->cid)
2374  *tq->cid = *GCC_get_id (ct->cc);
2377  "Sending payload of %s on %s\n",
2378  GCT_2s (t),
2379  GCC_2s (ct->cc));
2380  GCC_transmit (ct->cc,
2381  tq->env);
2382  if (NULL != tq->cont)
2383  tq->cont (tq->cont_cls,
2384  GCC_get_id (ct->cc));
2385  GNUNET_free (tq);
2386 }
2387 
2388 
2397 static void
2399  int is_ready)
2400 {
2401  struct CadetTConnection *ct = cls;
2402  struct CadetTunnel *t = ct->t;
2403 
2404  if (GNUNET_NO == is_ready)
2405  {
2407  "%s no longer ready for %s\n",
2408  GCC_2s (ct->cc),
2409  GCT_2s (t));
2411  return;
2412  }
2413  GNUNET_assert (GNUNET_NO == ct->is_ready);
2416  ct);
2418  t->num_busy_connections--;
2419  ct->is_ready = GNUNET_YES;
2422  ct);
2423  t->num_ready_connections++;
2424 
2426  "%s now ready for %s in state %s\n",
2427  GCC_2s (ct->cc),
2428  GCT_2s (t),
2429  estate2s (t->estate));
2430  switch (t->estate)
2431  {
2434  "Do not begin KX for %s if WE have no channels waiting. Retrying after %llu\n",
2435  GCT_2s (t),
2436  (unsigned long long) GNUNET_TIME_absolute_get_remaining (
2438  /* Do not begin KX if WE have no channels waiting! */
2441  return; /* wait for timeout before retrying */
2442  /* We are uninitialized, just transmit immediately,
2443  without undue delay. */
2444 
2446  "Why for %s \n",
2447  GCT_2s (t));
2448 
2449  if (NULL != t->kx_task)
2450  {
2452  t->kx_task = NULL;
2453  }
2454  send_kx (t,
2455  ct,
2456  &t->ax);
2457  if ((0 ==
2458  GCT_count_channels (t)) &&
2459  (NULL == t->destroy_task))
2460  {
2461  t->destroy_task
2463  &destroy_tunnel,
2464  t);
2465  }
2466  break;
2467 
2472  /* we're currently waiting for KX to complete, schedule job */
2473  if (NULL == t->kx_task)
2474  t->kx_task
2476  &retry_kx,
2477  t);
2478  break;
2479 
2480  case CADET_TUNNEL_KEY_OK:
2481  if (GNUNET_YES == t->kx_auth_requested)
2482  {
2485  return; /* wait for timeout */
2486  if (NULL != t->kx_task)
2487  {
2489  t->kx_task = NULL;
2490  }
2491  send_kx_auth (t,
2492  ct,
2493  &t->ax,
2494  GNUNET_NO);
2495  return;
2496  }
2498  ct);
2499  break;
2500  }
2501 }
2502 
2503 
2512 static void
2514 {
2515  struct CadetTunnel *t = cls;
2516  struct CadetTConnection *ct;
2517 
2518  t->send_task = NULL;
2519  if (NULL == t->tq_head)
2520  return; /* no messages pending right now */
2521  ct = get_ready_connection (t);
2522  if (NULL == ct)
2523  return; /* no connections ready */
2525  ct);
2526 }
2527 
2528 
2534 {
2538  unsigned int min_length;
2539 
2543  unsigned int max_length;
2544 
2549 
2554 
2559 
2565 
2569  double worst_score;
2570 
2575 };
2576 
2577 
2585 static void
2587  struct CadetTConnection *ct)
2588 {
2589  struct EvaluationSummary *es = cls;
2590  struct CadetConnection *cc = ct->cc;
2591  unsigned int ct_length;
2592  struct CadetPeerPath *ps;
2593  const struct CadetConnectionMetrics *metrics;
2594  GNUNET_CONTAINER_HeapCostType ct_desirability;
2595  struct GNUNET_TIME_Relative uptime;
2596  struct GNUNET_TIME_Relative last_use;
2597  double score;
2598  double success_rate;
2599 
2600  ps = GCC_get_path (cc,
2601  &ct_length);
2603  "Evaluating path %s of existing %s\n",
2604  GCPP_2s (ps),
2605  GCC_2s (cc));
2606  if (ps == es->path)
2607  {
2609  "Ignoring duplicate path %s.\n",
2610  GCPP_2s (es->path));
2611  es->duplicate = GNUNET_YES;
2612  return;
2613  }
2614  if (NULL != es->path)
2615  {
2616  int duplicate = GNUNET_YES;
2617 
2618  for (unsigned int i = 0; i < ct_length; i++)
2619  {
2620  GNUNET_assert (GCPP_get_length (es->path) > i);
2621  if (GCPP_get_peer_at_offset (es->path,
2622  i) !=
2624  i))
2625  {
2626  duplicate = GNUNET_NO;
2627  break;
2628  }
2629  }
2630  if (GNUNET_YES == duplicate)
2631  {
2633  "Ignoring overlapping path %s.\n",
2634  GCPP_2s (es->path));
2635  es->duplicate = GNUNET_YES;
2636  return;
2637  }
2638  else
2639  {
2641  "Known path %s differs from proposed path\n",
2642  GCPP_2s (ps));
2643  }
2644  }
2645 
2646  ct_desirability = GCPP_get_desirability (ps);
2647  metrics = GCC_get_metrics (cc);
2648  uptime = GNUNET_TIME_absolute_get_duration (metrics->age);
2649  last_use = GNUNET_TIME_absolute_get_duration (metrics->last_use);
2650  /* We add 1.0 here to avoid division by zero. */
2651  success_rate = (metrics->num_acked_transmissions + 1.0)
2652  / (metrics->num_successes + 1.0);
2653  score
2654  = ct_desirability
2655  + 100.0 / (1.0 + ct_length) /* longer paths = better */
2656  + sqrt (uptime.rel_value_us / 60000000LL) /* larger uptime = better */
2657  - last_use.rel_value_us / 1000L; /* longer idle = worse */
2658  score *= success_rate; /* weigh overall by success rate */
2659 
2660  if ((NULL == es->worst) ||
2661  (score < es->worst_score))
2662  {
2663  es->worst = ct;
2664  es->worst_score = score;
2665  }
2666  es->min_length = GNUNET_MIN (es->min_length,
2667  ct_length);
2668  es->max_length = GNUNET_MAX (es->max_length,
2669  ct_length);
2670  es->min_desire = GNUNET_MIN (es->min_desire,
2671  ct_desirability);
2672  es->max_desire = GNUNET_MAX (es->max_desire,
2673  ct_desirability);
2674 }
2675 
2676 
2686 static int
2687 consider_path_cb (void *cls,
2688  struct CadetPeerPath *path,
2689  unsigned int off)
2690 {
2691  struct CadetTunnel *t = cls;
2692  struct EvaluationSummary es;
2693  struct CadetTConnection *ct;
2694 
2695  GNUNET_assert (off < GCPP_get_length (path));
2697  off) == t->destination);
2698  es.min_length = UINT_MAX;
2699  es.max_length = 0;
2700  es.max_desire = 0;
2701  es.min_desire = UINT64_MAX;
2702  es.path = path;
2703  es.duplicate = GNUNET_NO;
2704  es.worst = NULL;
2705 
2706  /* Compute evaluation summary over existing connections. */
2708  "Evaluating proposed path %s for target %s\n",
2709  GCPP_2s (path),
2710  GCT_2s (t));
2711  /* FIXME: suspect this does not ACTUALLY iterate
2712  over all existing paths, otherwise dup detection
2713  should work!!! */
2716  &es);
2717  if (GNUNET_YES == es.duplicate)
2718  return GNUNET_YES;
2719 
2720  /* FIXME: not sure we should really just count
2721  'num_connections' here, as they may all have
2722  consistently failed to connect. */
2723 
2724  /* We iterate by increasing path length; if we have enough paths and
2725  this one is more than twice as long than what we are currently
2726  using, then ignore all of these super-long ones! */
2728  (es.min_length * 2 < off) &&
2729  (es.max_length < off))
2730  {
2732  "Ignoring paths of length %u, they are way too long.\n",
2733  es.min_length * 2);
2734  return GNUNET_NO;
2735  }
2736  /* If we have enough paths and this one looks no better, ignore it. */
2738  (es.min_length < GCPP_get_length (path)) &&
2739  (es.min_desire > GCPP_get_desirability (path)) &&
2740  (es.max_length < off))
2741  {
2743  "Ignoring path (%u/%llu) to %s, got something better already.\n",
2744  GCPP_get_length (path),
2745  (unsigned long long) GCPP_get_desirability (path),
2746  GCP_2s (t->destination));
2747  return GNUNET_YES;
2748  }
2749 
2750  /* Path is interesting (better by some metric, or we don't have
2751  enough paths yet). */
2752  ct = GNUNET_new (struct CadetTConnection);
2754  ct->t = t;
2755  ct->cc = GCC_create (t->destination,
2756  path,
2757  off,
2758  ct,
2760  ct);
2761 
2762  /* FIXME: schedule job to kill connection (and path?) if it takes
2763  too long to get ready! (And track performance data on how long
2764  other connections took with the tunnel!)
2765  => Note: to be done within 'connection'-logic! */
2768  ct);
2769  t->num_busy_connections++;
2771  "Found interesting path %s for %s, created %s\n",
2772  GCPP_2s (path),
2773  GCT_2s (t),
2774  GCC_2s (ct->cc));
2775  return GNUNET_YES;
2776 }
2777 
2778 
2792 static void
2794 {
2795  struct CadetTunnel *t = cls;
2796  struct GNUNET_TIME_Relative delay;
2797  struct EvaluationSummary es;
2798 
2799  t->maintain_connections_task = NULL;
2801  "Performing connection maintenance for %s.\n",
2802  GCT_2s (t));
2803 
2804  es.min_length = UINT_MAX;
2805  es.max_length = 0;
2806  es.max_desire = 0;
2807  es.min_desire = UINT64_MAX;
2808  es.path = NULL;
2809  es.worst = NULL;
2810  es.duplicate = GNUNET_NO;
2813  &es);
2814  if ((NULL != es.worst) &&
2816  {
2817  /* Clear out worst-performing connection 'es.worst'. */
2819  es.worst);
2820  }
2821 
2822  /* Consider additional paths */
2823  (void) GCP_iterate_paths (t->destination,
2825  t);
2826 
2827  /* FIXME: calculate when to try again based on how well we are doing;
2828  in particular, if we have to few connections, we might be able
2829  to do without this (as PATHS should tell us whenever a new path
2830  is available instantly; however, need to make sure this job is
2831  restarted after that happens).
2832  Furthermore, if the paths we do know are in a reasonably narrow
2833  quality band and are plentyful, we might also consider us stabilized
2834  and then reduce the frequency accordingly. */delay = GNUNET_TIME_UNIT_MINUTES;
2838  t);
2839 }
2840 
2841 
2850 void
2852  struct CadetPeerPath *p,
2853  unsigned int off)
2854 {
2856  "Considering %s for %s (offset %u)\n",
2857  GCPP_2s (p),
2858  GCT_2s (t),
2859  off);
2860  (void) consider_path_cb (t,
2861  p,
2862  off);
2863 }
2864 
2865 
2872 static void
2874  const struct GNUNET_MessageHeader *msg)
2875 {
2876  struct CadetTunnel *t = cls;
2877 
2879  "Received KEEPALIVE on %s\n",
2880  GCT_2s (t));
2882  "# keepalives received",
2883  1,
2884  GNUNET_NO);
2885 }
2886 
2887 
2895 static int
2898 {
2899  return GNUNET_OK;
2900 }
2901 
2902 
2910 static void
2913 {
2914  struct CadetTunnel *t = cls;
2915  struct CadetChannel *ch;
2916 
2917  ch = lookup_channel (t,
2918  msg->ctn);
2919  if (NULL == ch)
2920  {
2921  /* We don't know about such a channel, might have been destroyed on our
2922  end in the meantime, or never existed. Send back a DESTROY. */
2924  "Received %u bytes of application data for unknown channel %u, sending DESTROY\n",
2925  (unsigned int) (ntohs (msg->header.size) - sizeof(*msg)),
2926  ntohl (msg->ctn.cn));
2928  msg->ctn);
2929  return;
2930  }
2932  GCC_get_id (t->current_ct->cc),
2933  msg);
2934 }
2935 
2936 
2945 static void
2947  const struct GNUNET_CADET_ChannelDataAckMessage *ack)
2948 {
2949  struct CadetTunnel *t = cls;
2950  struct CadetChannel *ch;
2951 
2952  ch = lookup_channel (t,
2953  ack->ctn);
2954  if (NULL == ch)
2955  {
2956  /* We don't know about such a channel, might have been destroyed on our
2957  end in the meantime, or never existed. Send back a DESTROY. */
2959  "Received DATA_ACK for unknown channel %u, sending DESTROY\n",
2960  ntohl (ack->ctn.cn));
2962  ack->ctn);
2963  return;
2964  }
2966  GCC_get_id (t->current_ct->cc),
2967  ack);
2968 }
2969 
2970 
2978 static void
2980  const struct
2982 {
2983  struct CadetTunnel *t = cls;
2984  struct CadetChannel *ch;
2985 
2987  ntohl (copen->ctn.cn));
2988  if (NULL != ch)
2989  {
2991  "Received duplicate channel CHANNEL_OPEN on h_port %s from %s (%s), resending ACK\n",
2992  GNUNET_h2s (&copen->h_port),
2993  GCT_2s (t),
2994  GCCH_2s (ch));
2996  GCC_get_id (t->current_ct->cc));
2997  return;
2998  }
3000  "Received CHANNEL_OPEN on h_port %s from %s\n",
3001  GNUNET_h2s (&copen->h_port),
3002  GCT_2s (t));
3003  ch = GCCH_channel_incoming_new (t,
3004  copen->ctn,
3005  &copen->h_port,
3006  ntohl (copen->opt));
3007  if (NULL != t->destroy_task)
3008  {
3010  t->destroy_task = NULL;
3011  }
3014  ntohl (copen->ctn.cn),
3015  ch,
3017 }
3018 
3019 
3026 void
3029 {
3031 
3033  "Sending DESTORY message for channel ID %u\n",
3034  ntohl (ctn.cn));
3035  msg.header.size = htons (sizeof(msg));
3037  msg.reserved = htonl (0);
3038  msg.ctn = ctn;
3039  GCT_send (t,
3040  &msg.header,
3041  NULL,
3042  NULL,
3043  &ctn);
3044 }
3045 
3046 
3055 static void
3057  const struct
3059 {
3060  struct CadetTunnel *t = cls;
3061  struct CadetChannel *ch;
3062 
3063  ch = lookup_channel (t,
3064  cm->ctn);
3065  if (NULL == ch)
3066  {
3067  /* We don't know about such a channel, might have been destroyed on our
3068  end in the meantime, or never existed. Send back a DESTROY. */
3070  "Received channel OPEN_ACK for unknown channel %u, sending DESTROY\n",
3071  ntohl (cm->ctn.cn));
3073  cm->ctn);
3074  return;
3075  }
3077  "Received channel OPEN_ACK on channel %s from %s\n",
3078  GCCH_2s (ch),
3079  GCT_2s (t));
3081  GCC_get_id (t->current_ct->cc),
3082  &cm->port);
3083 }
3084 
3085 
3093 static void
3095  const struct
3097 {
3098  struct CadetTunnel *t = cls;
3099  struct CadetChannel *ch;
3100 
3101  ch = lookup_channel (t,
3102  cm->ctn);
3103  if (NULL == ch)
3104  {
3105  /* We don't know about such a channel, might have been destroyed on our
3106  end in the meantime, or never existed. */
3108  "Received channel DESTORY for unknown channel %u. Ignoring.\n",
3109  ntohl (cm->ctn.cn));
3110  return;
3111  }
3113  "Received channel DESTROY on %s from %s\n",
3114  GCCH_2s (ch),
3115  GCT_2s (t));
3117  GCC_get_id (t->current_ct->cc));
3118 }
3119 
3120 
3131 static int
3132 handle_decrypted (void *cls,
3133  const struct GNUNET_MessageHeader *msg)
3134 {
3135  struct CadetTunnel *t = cls;
3136 
3137  GNUNET_assert (NULL != t->current_ct);
3139  msg);
3140  return GNUNET_OK;
3141 }
3142 
3143 
3151 static void
3153  enum GNUNET_MQ_Error error)
3154 {
3155  GNUNET_break_op (0);
3156 }
3157 
3158 
3166 struct CadetTunnel *
3168 {
3169  struct CadetTunnel *t = GNUNET_new (struct CadetTunnel);
3170  struct GNUNET_MQ_MessageHandler handlers[] = {
3171  GNUNET_MQ_hd_fixed_size (plaintext_keepalive,
3173  struct GNUNET_MessageHeader,
3174  t),
3175  GNUNET_MQ_hd_var_size (plaintext_data,
3178  t),
3179  GNUNET_MQ_hd_fixed_size (plaintext_data_ack,
3182  t),
3183  GNUNET_MQ_hd_fixed_size (plaintext_channel_open,
3186  t),
3187  GNUNET_MQ_hd_fixed_size (plaintext_channel_open_ack,
3190  t),
3191  GNUNET_MQ_hd_fixed_size (plaintext_channel_destroy,
3194  t),
3196  };
3197 
3199  new_ephemeral (&t->ax);
3201  t->destination = destination;
3205  t);
3206  t->mq = GNUNET_MQ_queue_for_callbacks (NULL,
3207  NULL,
3208  NULL,
3209  NULL,
3210  handlers,
3212  t);
3214  t);
3215  return t;
3216 }
3217 
3218 
3229 int
3231  const struct
3233  struct CadetPeerPath *path)
3234 {
3235  struct CadetTConnection *ct;
3236 
3237  ct = GNUNET_new (struct CadetTConnection);
3239  ct->t = t;
3240  ct->cc = GCC_create_inbound (t->destination,
3241  path,
3242  ct,
3243  cid,
3245  ct);
3246  if (NULL == ct->cc)
3247  {
3249  "%s refused inbound %s (duplicate)\n",
3250  GCT_2s (t),
3251  GCC_2s (ct->cc));
3252  GNUNET_free (ct);
3253  return GNUNET_SYSERR;
3254  }
3255  /* FIXME: schedule job to kill connection (and path?) if it takes
3256  too long to get ready! (And track performance data on how long
3257  other connections took with the tunnel!)
3258  => Note: to be done within 'connection'-logic! */
3261  ct);
3262  t->num_busy_connections++;
3264  "%s has new %s\n",
3265  GCT_2s (t),
3266  GCC_2s (ct->cc));
3267  return GNUNET_OK;
3268 }
3269 
3270 
3277 void
3280 {
3281  struct CadetTunnel *t = ct->t;
3282  uint16_t size = ntohs (msg->header.size);
3283  char cbuf[size] GNUNET_ALIGN;
3284  ssize_t decrypted_size;
3285 
3287  "%s received %u bytes of encrypted data in state %d\n",
3288  GCT_2s (t),
3289  (unsigned int) size,
3290  t->estate);
3291 
3292  switch (t->estate)
3293  {
3296  /* We did not even SEND our KX, how can the other peer
3297  send us encrypted data? Must have been that we went
3298  down and the other peer still things we are up.
3299  Let's send it KX back. */
3301  "# received encrypted without any KX",
3302  1,
3303  GNUNET_NO);
3304  if (NULL != t->kx_task)
3305  {
3307  t->kx_task = NULL;
3308  }
3309  send_kx (t,
3310  ct,
3311  &t->ax);
3312  return;
3313 
3315  /* We send KX, and other peer send KX to us at the same time.
3316  Neither KX is AUTH'ed, so let's try KX_AUTH this time. */
3318  "# received encrypted without KX_AUTH",
3319  1,
3320  GNUNET_NO);
3321  if (NULL != t->kx_task)
3322  {
3324  t->kx_task = NULL;
3325  }
3326  send_kx_auth (t,
3327  ct,
3328  &t->ax,
3329  GNUNET_YES);
3330  return;
3331 
3333  /* We did not get the KX of the other peer, but that
3334  might have been lost. Send our KX again immediately. */
3336  "# received encrypted without KX",
3337  1,
3338  GNUNET_NO);
3339  if (NULL != t->kx_task)
3340  {
3342  t->kx_task = NULL;
3343  }
3344  send_kx (t,
3345  ct,
3346  &t->ax);
3347  return;
3348 
3350  /* Great, first payload, we might graduate to OK! */
3351  case CADET_TUNNEL_KEY_OK:
3352  /* We are up and running, all good. */
3353  break;
3354  }
3355 
3356  decrypted_size = -1;
3357  if (CADET_TUNNEL_KEY_OK == t->estate)
3358  {
3359  /* We have well-established key material available,
3360  try that. (This is the common case.) */
3361  decrypted_size = t_ax_decrypt_and_validate (&t->ax,
3362  cbuf,
3363  msg,
3364  size);
3365  }
3366 
3367  if ((-1 == decrypted_size) &&
3368  (NULL != t->unverified_ax))
3369  {
3370  /* We have un-authenticated KX material available. We should try
3371  this as a back-up option, in case the sender crashed and
3372  switched keys. */
3373  decrypted_size = t_ax_decrypt_and_validate (t->unverified_ax,
3374  cbuf,
3375  msg,
3376  size);
3377  if (-1 != decrypted_size)
3378  {
3379  /* It worked! Treat this as authentication of the AX data! */
3380  cleanup_ax (&t->ax);
3381  t->ax = *t->unverified_ax;
3383  t->unverified_ax = NULL;
3384  }
3386  {
3387  /* First time it worked, move tunnel into production! */
3388  GCT_change_estate (t,
3390  if (NULL != t->send_task)
3393  t);
3394  }
3395  }
3396  if (NULL != t->unverified_ax)
3397  {
3398  /* We had unverified KX material that was useless; so increment
3399  counter and eventually move to ignore it. Note that we even do
3400  this increment if we successfully decrypted with the old KX
3401  material and thus didn't even both with the new one. This is
3402  the ideal case, as a malicious injection of bogus KX data
3403  basically only causes us to increment a counter a few times. */t->unverified_attempts++;
3405  "Failed to decrypt message with unverified KX data %u times\n",
3406  t->unverified_attempts);
3408  {
3411  t->unverified_ax = NULL;
3412  }
3413  }
3414 
3415  if (-1 == decrypted_size)
3416  {
3417  /* Decryption failed for good, complain. */
3419  "%s failed to decrypt and validate encrypted data, retrying KX\n",
3420  GCT_2s (t));
3422  "# unable to decrypt",
3423  1,
3424  GNUNET_NO);
3425  if (NULL != t->kx_task)
3426  {
3428  t->kx_task = NULL;
3429  }
3430  send_kx (t,
3431  ct,
3432  &t->ax);
3433  return;
3434  }
3436  "# decrypted bytes",
3437  decrypted_size,
3438  GNUNET_NO);
3439 
3440  /* The MST will ultimately call #handle_decrypted() on each message. */
3441  t->current_ct = ct;
3444  cbuf,
3445  decrypted_size,
3446  GNUNET_YES,
3447  GNUNET_NO));
3448  t->current_ct = NULL;
3449 }
3450 
3451 
3463 struct CadetTunnelQueueEntry *
3465  const struct GNUNET_MessageHeader *message,
3467  void *cont_cls,
3469 {
3470  struct CadetTunnelQueueEntry *tq;
3471  uint16_t payload_size;
3472  struct GNUNET_MQ_Envelope *env;
3473  struct GNUNET_CADET_TunnelEncryptedMessage *ax_msg;
3474  struct CadetChannel *ch;
3475 
3476  if (NULL != ctn)
3477  {
3478  ch = lookup_channel (t,
3479  *ctn);
3480  if ((NULL != ch) && GCCH_is_type_to_drop (ch, message))
3481  {
3482  GNUNET_break (0);
3483  return NULL;
3484  }
3485  }
3486 
3487  if (CADET_TUNNEL_KEY_OK != t->estate)
3488  {
3489  GNUNET_break (0);
3490  return NULL;
3491  }
3492  payload_size = ntohs (message->size);
3494  "Encrypting %u bytes for %s\n",
3495  (unsigned int) payload_size,
3496  GCT_2s (t));
3497  env = GNUNET_MQ_msg_extra (ax_msg,
3498  payload_size,
3500  t_ax_encrypt (&t->ax,
3501  &ax_msg[1],
3502  message,
3503  payload_size);
3505  "# encrypted bytes",
3506  payload_size,
3507  GNUNET_NO);
3508  ax_msg->ax_header.Ns = htonl (t->ax.Ns++);
3509  ax_msg->ax_header.PNs = htonl (t->ax.PNs);
3510  /* FIXME: we should do this once, not once per message;
3511  this is a point multiplication, and DHRs does not
3512  change all the time. */
3514  &ax_msg->ax_header.DHRs);
3515  t_h_encrypt (&t->ax,
3516  ax_msg);
3517  t_hmac (&ax_msg->ax_header,
3518  sizeof(struct GNUNET_CADET_AxHeader) + payload_size,
3519  0,
3520  &t->ax.HKs,
3521  &ax_msg->hmac);
3522 
3523  tq = GNUNET_malloc (sizeof(*tq));
3524  tq->t = t;
3525  tq->env = env;
3526  tq->cid = &ax_msg->cid; /* will initialize 'ax_msg->cid' once we know the connection */
3527  tq->cont = cont;
3528  tq->cont_cls = cont_cls;
3530  t->tq_tail,
3531  tq);
3532  if (NULL != t->send_task)
3534  t->send_task
3536  t);
3537  return tq;
3538 }
3539 
3540 
3550 void
3552 {
3553  struct CadetTunnel *t = tq->t;
3554 
3556  t->tq_tail,
3557  tq);
3558  GNUNET_MQ_discard (tq->env);
3559  GNUNET_free (tq);
3560 }
3561 
3562 
3570 void
3573  void *iter_cls)
3574 {
3575  struct CadetTConnection *n;
3576 
3577  for (struct CadetTConnection *ct = t->connection_ready_head;
3578  NULL != ct;
3579  ct = n)
3580  {
3581  n = ct->next;
3582  iter (iter_cls,
3583  ct);
3584  }
3585  for (struct CadetTConnection *ct = t->connection_busy_head;
3586  NULL != ct;
3587  ct = n)
3588  {
3589  n = ct->next;
3590  iter (iter_cls,
3591  ct);
3592  }
3593 }
3594 
3595 
3600 {
3605 
3609  void *iter_cls;
3610 };
3611 
3612 
3621 static int
3623  uint32_t key,
3624  void *value)
3625 {
3626  struct ChanIterCls *ctx = cls;
3627  struct CadetChannel *ch = value;
3628 
3629  ctx->iter (ctx->iter_cls,
3630  ch);
3631  return GNUNET_OK;
3632 }
3633 
3634 
3642 void
3644  GCT_ChannelIterator iter,
3645  void *iter_cls)
3646 {
3647  struct ChanIterCls ctx;
3648 
3649  ctx.iter = iter;
3650  ctx.iter_cls = iter_cls;
3653  &ctx);
3654 }
3655 
3656 
3665 static int
3666 debug_channel (void *cls,
3667  uint32_t key,
3668  void *value)
3669 {
3670  const enum GNUNET_ErrorType *level = cls;
3671  struct CadetChannel *ch = value;
3672 
3673  GCCH_debug (ch, *level);
3674  return GNUNET_OK;
3675 }
3676 
3677 
3678 #define LOG2(level, ...) GNUNET_log_from_nocheck (level, "cadet-tun", \
3679  __VA_ARGS__)
3680 
3681 
3688 void
3689 GCT_debug (const struct CadetTunnel *t,
3690  enum GNUNET_ErrorType level)
3691 {
3692 #if ! defined(GNUNET_CULL_LOGGING)
3693  struct CadetTConnection *iter_c;
3694  int do_log;
3695 
3697  "cadet-tun",
3698  __FILE__, __FUNCTION__, __LINE__);
3699  if (0 == do_log)
3700  return;
3701 
3702  LOG2 (level,
3703  "TTT TUNNEL TOWARDS %s in estate %s tq_len: %u #cons: %u\n",
3704  GCT_2s (t),
3705  estate2s (t->estate),
3706  t->tq_len,
3708  LOG2 (level,
3709  "TTT channels:\n");
3711  &debug_channel,
3712  &level);
3713  LOG2 (level,
3714  "TTT connections:\n");
3715  for (iter_c = t->connection_ready_head; NULL != iter_c; iter_c = iter_c->next)
3716  GCC_debug (iter_c->cc,
3717  level);
3718  for (iter_c = t->connection_busy_head; NULL != iter_c; iter_c = iter_c->next)
3719  GCC_debug (iter_c->cc,
3720  level);
3721 
3722  LOG2 (level,
3723  "TTT TUNNEL END\n");
3724 #endif
3725 }
3726 
3727 
3728 /* end of gnunet-service-cadet_tunnels.c */
struct CadetTunnelAxolotl ax
Axolotl info.
#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.
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.
int GCT_alice_or_betty(const struct GNUNET_PeerIdentity *other)
Am I Alice or Betty (some call her Bob), or talking to myself?
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:470
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 ...
#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.
#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.
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:850
struct CadetTConnection * connection_ready_head
DLL of ready connections that are actively used to reach the destination peer.
static int ret
Return value of the commandline.
Definition: gnunet-abd.c:81
#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.
struct CadetTunnelQueueEntry * GCT_send(struct CadetTunnel *t, const struct GNUNET_MessageHeader *message, GCT_SendContinuation cont, void *cont_cls, struct GNUNET_CADET_ChannelTunnelNumber *ctn)
Sends an already built message on a tunnel, encrypting it and choosing the best connection if not pro...
static void send_kx(struct CadetTunnel *t, struct CadetTConnection *ct, struct CadetTunnelAxolotl *ax)
Send a KX message.
void * iter_cls
Closure for iter.
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).
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:395
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 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:455
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.
int GNUNET_snprintf(char *buf, size_t size, const char *format,...) __attribute__((format(printf
Like snprintf, just aborts if the buffer is of insufficient size.
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.
void GNUNET_CRYPTO_ecdhe_key_create(struct GNUNET_CRYPTO_EcdhePrivateKey *pk)
Create a new private key.
Definition: crypto_ecc.c:508
#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:1269
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:565
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:1024
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:411
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:48
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 GNUNET_STATISTICS_Handle * stats
Handle to the statistics service.
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:95
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:1296
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:93
#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:85
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:114
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:202
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:1084
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
int GCCH_is_type_to_drop(struct CadetChannel *ch, const struct GNUNET_MessageHeader *message)
Check if type of message is the one to drop.
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:323
#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.
static unsigned int size
Size of the "table".
Definition: peer.c:67
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:215
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:193
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:85
struct GNUNET_CRYPTO_SymmetricSessionKey RK
32-byte root key which gets updated by DH ratchet.
static struct GNUNET_CRYPTO_PowSalt salt
Salt for PoW calcualations.
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:375
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:134
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:837
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:1246
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:373
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:90
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:972
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...