src/vpn/gnunet-service-dns.c

   1 /*
   2      This file is part of GNUnet.
   3      (C) 2009 Christian Grothoff (and other contributing authors)
   4
   5      GNUnet is free software; you can redistribute it and/or modify
   6      it under the terms of the GNU General Public License as published
   7      by the Free Software Foundation; either version 3, or (at your
   8      option) any later version.
   9
  10      GNUnet is distributed in the hope that it will be useful, but
  11      WITHOUT ANY WARRANTY; without even the implied warranty of
  12      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13      General Public License for more details.
  14
  15      You should have received a copy of the GNU General Public License
  16      along with GNUnet; see the file COPYING.  If not, write to the
  17      Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18      Boston, MA 02111-1307, USA.
  19 */
  20
  21 /**
  22  * @file vpn/gnunet-service-dns.c
  23  * @author Philipp Toelke
  24  */
  25 #include "platform.h"
  26 #include "gnunet_getopt_lib.h"
  27 #include "gnunet_service_lib.h"
  28 #include <gnunet_constants.h>
  29 #include "gnunet_network_lib.h"
  30 #include "gnunet_os_lib.h"
  31 #include "gnunet-service-dns-p.h"
  32 #include "gnunet_protocols.h"
  33 #include "gnunet_applications.h"
  34 #include "gnunet-vpn-packet.h"
  35 #include "gnunet_container_lib.h"
  36 #include "gnunet-dns-parser.h"
  37 #include "gnunet_dht_service.h"
  38 #include "gnunet_block_lib.h"
  39 #include "block_dns.h"
  40 #include "gnunet_crypto_lib.h"
  41 #include "gnunet_mesh_service.h"
  42 #include "gnunet_signatures.h"
  43
  44 struct GNUNET_MESH_Handle *mesh_handle;
  45
  46 /**
  47  * The UDP-Socket through which DNS-Resolves will be sent if they are not to be
  48  * sent through gnunet. The port of this socket will not be hijacked.
  49  */
  50 static struct GNUNET_NETWORK_Handle *dnsout;
  51
  52 /**
  53  * The port bound to the socket dnsout
  54  */
  55 static unsigned short dnsoutport;
  56
  57 /**
  58  * A handle to the DHT-Service
  59  */
  60 static struct GNUNET_DHT_Handle *dht;
  61
  62 /**
  63  * The configuration to use
  64  */
  65 static const struct GNUNET_CONFIGURATION_Handle *cfg;
  66
  67 /**
  68  * A list of DNS-Responses that have to be sent to the requesting client
  69  */
  70 static struct answer_packet_list *head;
  71
  72 /**
  73  * The tail of the list of DNS-responses
  74  */
  75 static struct answer_packet_list *tail;
  76
  77 /**
  78  * A structure containing a mapping from network-byte-ordered DNS-id (16 bit) to
  79  * some information needed to handle this query
  80  *
  81  * It currently allocates at least
  82  * (1 + machine-width + machine-width + 32 + 32 + 16 + machine-width + 8) * 65536 bit
  83  * = 17 MiB on 64 bit.
  84  * = 11 MiB on 32 bit.
  85  */
  86 static struct
  87 {
  88   unsigned valid:1;
  89   struct GNUNET_SERVER_Client *client;
  90   struct GNUNET_MESH_Tunnel *tunnel;
  91   uint32_t local_ip;
  92   uint32_t remote_ip;
  93   uint16_t local_port;
  94   char *name;
  95   uint8_t namelen;
  96 } query_states[UINT16_MAX];
  97
  98 /**
  99  * A struct used to give more than one value as
 100  * closure to receive_dht
 101  */
 102 struct receive_dht_cls
 103 {
 104   uint16_t id;
 105   struct GNUNET_DHT_GetHandle *handle;
 106 };
 107
 108 struct tunnel_notify_queue
 109 {
 110   struct tunnel_notify_queue *next;
 111   struct tunnel_notify_queue *prev;
 112   void *cls;
 113   size_t len;
 114   GNUNET_CONNECTION_TransmitReadyNotify cb;
 115 };
 116
 117 /**
 118  * Hijack all outgoing DNS-Traffic but for traffic leaving "our" port.
 119  */
 120 static void
 121 hijack (void *cls
 122         __attribute__ ((unused)), const struct GNUNET_SCHEDULER_TaskContext *tc)
 123 {
 124   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
 125     return;
 126
 127   if (0 == dnsoutport)
 128   {
 129     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
 130                 "Delaying the hijacking, port is still %d!\n", dnsoutport);
 131     GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
 132     return;
 133   }
 134
 135   char port_s[6];
 136   char *virt_dns;
 137   struct GNUNET_OS_Process *proc;
 138
 139   if (GNUNET_SYSERR ==
 140       GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS", &virt_dns))
 141   {
 142     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 143                 "No entry 'VIRTDNS' in configuration!\n");
 144     exit (1);
 145   }
 146
 147   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Hijacking, port is %d\n", dnsoutport);
 148   snprintf (port_s, 6, "%d", dnsoutport);
 149   if (NULL != (proc = GNUNET_OS_start_process (NULL,
 150                                                NULL,
 151                                                "gnunet-helper-hijack-dns",
 152                                                "gnunet-hijack-dns",
 153                                                port_s, virt_dns, NULL)))
 154     GNUNET_OS_process_close (proc);
 155   GNUNET_free (virt_dns);
 156 }
 157
 158 /**
 159  * Delete the hijacking-routes
 160  */
 161 static void
 162 unhijack (unsigned short port)
 163 {
 164   char port_s[6];
 165   char *virt_dns;
 166   struct GNUNET_OS_Process *proc;
 167
 168   if (GNUNET_SYSERR ==
 169       GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS", &virt_dns))
 170   {
 171     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 172                 "No entry 'VIRTDNS' in configuration!\n");
 173     exit (1);
 174   }
 175
 176   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "unHijacking, port is %d\n", port);
 177   snprintf (port_s, 6, "%d", port);
 178   if (NULL != (proc = GNUNET_OS_start_process (NULL,
 179                                                NULL,
 180                                                "gnunet-helper-hijack-dns",
 181                                                "gnunet-hijack-dns",
 182                                                "-d", port_s, virt_dns, NULL)))
 183     GNUNET_OS_process_close (proc);
 184   GNUNET_free (virt_dns);
 185 }
 186
 187 /**
 188  * Send the DNS-Response to the client. Gets called via the notify_transmit_ready-
 189  * system.
 190  */
 191 static size_t
 192 send_answer (void *cls, size_t size, void *buf)
 193 {
 194   struct answer_packet_list *query = head;
 195   size_t len = ntohs (query->pkt.hdr.size);
 196
 197   GNUNET_assert (len <= size);
 198
 199   memcpy (buf, &query->pkt.hdr, len);
 200
 201   GNUNET_CONTAINER_DLL_remove (head, tail, query);
 202
 203   GNUNET_free (query);
 204
 205   /* When more data is to be sent, reschedule */
 206   if (head != NULL)
 207     GNUNET_SERVER_notify_transmit_ready (cls,
 208                                          ntohs (head->pkt.hdr.size),
 209                                          GNUNET_TIME_UNIT_FOREVER_REL,
 210                                          &send_answer, cls);
 211
 212   return len;
 213 }
 214
 215 struct tunnel_cls
 216 {
 217   struct GNUNET_MESH_Tunnel *tunnel GNUNET_PACKED;
 218   struct GNUNET_MessageHeader hdr;
 219   struct dns_pkt dns;
 220 };
 221
 222 struct tunnel_cls *remote_pending[UINT16_MAX];
 223
 224 static size_t
 225 mesh_send_response (void *cls, size_t size, void *buf)
 226 {
 227   GNUNET_assert (size >= sizeof (struct GNUNET_MessageHeader));
 228   struct GNUNET_MessageHeader *hdr = buf;
 229   uint32_t *sz = cls;
 230   struct GNUNET_MESH_Tunnel **tunnel = (struct GNUNET_MESH_Tunnel **) (sz + 1);
 231   struct dns_pkt *dns = (struct dns_pkt *) (tunnel + 1);
 232
 233   hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_REMOTE_ANSWER_DNS);
 234   hdr->size = htons (*sz + sizeof (struct GNUNET_MessageHeader));
 235
 236   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 237               "Sending response, size=%d, sz=%d, sz+hdr=%d\n", size, *sz,
 238               *sz + sizeof (struct GNUNET_MessageHeader));
 239
 240   GNUNET_assert (size >= (*sz + sizeof (struct GNUNET_MessageHeader)));
 241
 242   memcpy (hdr + 1, dns, *sz);
 243
 244   if (NULL != GNUNET_MESH_tunnel_get_head (*tunnel))
 245   {
 246     struct tunnel_notify_queue *element = GNUNET_MESH_tunnel_get_head (*tunnel);
 247     struct tunnel_notify_queue *head = GNUNET_MESH_tunnel_get_head (*tunnel);
 248     struct tunnel_notify_queue *tail = GNUNET_MESH_tunnel_get_tail (*tunnel);
 249
 250     GNUNET_CONTAINER_DLL_remove (head, tail, element);
 251
 252     GNUNET_MESH_tunnel_set_head (*tunnel, head);
 253     GNUNET_MESH_tunnel_set_tail (*tunnel, tail);
 254     struct GNUNET_MESH_TransmitHandle *th =
 255         GNUNET_MESH_notify_transmit_ready (*tunnel,
 256                                            GNUNET_NO,
 257                                            42,
 258                                            GNUNET_TIME_relative_divide
 259                                            (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
 260                                            (const struct GNUNET_PeerIdentity *)
 261                                            NULL, element->len,
 262                                            element->cb, element->cls);
 263
 264     /* save the handle */
 265     GNUNET_MESH_tunnel_set_data (*tunnel, th);
 266   }
 267
 268   GNUNET_free (cls);
 269
 270   return ntohs (hdr->size);
 271 }
 272
 273 static size_t
 274 mesh_send (void *cls, size_t size, void *buf)
 275 {
 276   struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
 277
 278   GNUNET_MESH_tunnel_set_data (cls_->tunnel, NULL);
 279
 280   GNUNET_assert (cls_->hdr.size <= size);
 281
 282   size = cls_->hdr.size;
 283   cls_->hdr.size = htons (cls_->hdr.size);
 284
 285   memcpy (buf, &cls_->hdr, size);
 286
 287   if (NULL != GNUNET_MESH_tunnel_get_head (cls_->tunnel))
 288   {
 289     struct tunnel_notify_queue *element =
 290         GNUNET_MESH_tunnel_get_head (cls_->tunnel);
 291     struct tunnel_notify_queue *head =
 292         GNUNET_MESH_tunnel_get_head (cls_->tunnel);
 293     struct tunnel_notify_queue *tail =
 294         GNUNET_MESH_tunnel_get_tail (cls_->tunnel);
 295
 296     GNUNET_CONTAINER_DLL_remove (head, tail, element);
 297
 298     GNUNET_MESH_tunnel_set_head (cls_->tunnel, head);
 299     GNUNET_MESH_tunnel_set_tail (cls_->tunnel, tail);
 300     struct GNUNET_MESH_TransmitHandle *th =
 301         GNUNET_MESH_notify_transmit_ready (cls_->tunnel,
 302                                            GNUNET_NO,
 303                                            42,
 304                                            GNUNET_TIME_relative_divide
 305                                            (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
 306                                            (const struct GNUNET_PeerIdentity *)
 307                                            NULL, element->len,
 308                                            element->cb, element->cls);
 309
 310     /* save the handle */
 311     GNUNET_MESH_tunnel_set_data (cls_->tunnel, th);
 312     GNUNET_free (element);
 313   }
 314
 315   return size;
 316 }
 317
 318
 319 void
 320 mesh_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
 321               const struct GNUNET_TRANSPORT_ATS_Information *atsi
 322               __attribute__ ((unused)))
 323 {
 324   if (NULL == peer)
 325     return;
 326   struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
 327
 328   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 329               "Connected to peer %s, %x, sending query with id %d\n",
 330               GNUNET_i2s (peer), peer, ntohs (cls_->dns.s.id));
 331
 332   if (NULL == GNUNET_MESH_tunnel_get_data (cls_->tunnel))
 333   {
 334     struct GNUNET_MESH_TransmitHandle *th =
 335         GNUNET_MESH_notify_transmit_ready (cls_->tunnel,
 336                                            GNUNET_YES,
 337                                            42,
 338                                            GNUNET_TIME_UNIT_MINUTES,
 339                                            NULL,
 340                                            cls_->hdr.size,
 341                                            mesh_send,
 342                                            cls);
 343
 344     GNUNET_MESH_tunnel_set_data (cls_->tunnel, th);
 345   }
 346   else
 347   {
 348     struct tunnel_notify_queue *head =
 349         GNUNET_MESH_tunnel_get_head (cls_->tunnel);
 350     struct tunnel_notify_queue *tail =
 351         GNUNET_MESH_tunnel_get_tail (cls_->tunnel);
 352
 353     struct tunnel_notify_queue *element =
 354         GNUNET_malloc (sizeof (struct tunnel_notify_queue));
 355     element->cls = cls;
 356     element->len = cls_->hdr.size;
 357     element->cb = mesh_send;
 358
 359     GNUNET_CONTAINER_DLL_insert_tail (head, tail, element);
 360     GNUNET_MESH_tunnel_set_head (cls_->tunnel, head);
 361     GNUNET_MESH_tunnel_set_tail (cls_->tunnel, tail);
 362   }
 363 }
 364
 365
 366 static void
 367 send_mesh_query (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 368 {
 369   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
 370     return;
 371
 372   struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
 373
 374   cls_->tunnel = GNUNET_MESH_peer_request_connect_by_type (mesh_handle,
 375                                                            GNUNET_TIME_UNIT_HOURS,
 376                                                            GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
 377                                                            mesh_connect,
 378                                                            NULL, cls_);
 379
 380   remote_pending[cls_->dns.s.id] = cls_;
 381 }
 382
 383 static int
 384 receive_mesh_query (void *cls __attribute__ ((unused)),
 385                     struct GNUNET_MESH_Tunnel *tunnel,
 386                     void **ctx __attribute__ ((unused)),
 387                     const struct GNUNET_PeerIdentity *sender
 388                     __attribute__ ((unused)),
 389                     const struct GNUNET_MessageHeader *message,
 390                     const struct GNUNET_TRANSPORT_ATS_Information *atsi
 391                     __attribute__ ((unused)))
 392 {
 393   struct dns_pkt *dns = (struct dns_pkt *) (message + 1);
 394
 395   struct sockaddr_in dest;
 396
 397   memset (&dest, 0, sizeof dest);
 398   dest.sin_port = htons (53);
 399   /* TODO: read from config */
 400   inet_pton (AF_INET, "8.8.8.8", &dest.sin_addr);
 401
 402   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Querying for remote, id=%d\n",
 403               ntohs (dns->s.id));
 404   query_states[dns->s.id].tunnel = tunnel;
 405   query_states[dns->s.id].valid = GNUNET_YES;
 406
 407   GNUNET_NETWORK_socket_sendto (dnsout,
 408                                 dns,
 409                                 ntohs (message->size) -
 410                                 sizeof (struct GNUNET_MessageHeader),
 411                                 (struct sockaddr *) &dest, sizeof dest);
 412
 413   return GNUNET_SYSERR;
 414 }
 415
 416 static int
 417 receive_mesh_answer (void *cls __attribute__ ((unused)),
 418                      struct GNUNET_MESH_Tunnel *tunnel,
 419                      void **ctx __attribute__ ((unused)),
 420                      const struct GNUNET_PeerIdentity *sender,
 421                      const struct GNUNET_MessageHeader *message,
 422                      const struct GNUNET_TRANSPORT_ATS_Information *atsi
 423                      __attribute__ ((unused)))
 424 {
 425   /* TODo: size check */
 426   struct dns_pkt *dns = (struct dns_pkt *) (message + 1);
 427
 428   /* They sent us a packet we were not waiting for */
 429   if (remote_pending[dns->s.id] == NULL
 430       || remote_pending[dns->s.id]->tunnel != tunnel)
 431     return GNUNET_OK;
 432
 433   GNUNET_free (remote_pending[dns->s.id]);
 434   remote_pending[dns->s.id] = NULL;
 435
 436   if (query_states[dns->s.id].valid != GNUNET_YES)
 437     return GNUNET_SYSERR;
 438   query_states[dns->s.id].valid = GNUNET_NO;
 439
 440   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 441               "Received answer from peer %s, dns-id %d\n", GNUNET_i2s (sender),
 442               ntohs (dns->s.id));
 443
 444   size_t len = sizeof (struct answer_packet) - 1 + sizeof (struct dns_static) + query_states[dns->s.id].namelen + sizeof (struct dns_query_line) + 2    /* To hold the pointer (as defined in RFC1035) to the name */
 445       + sizeof (struct dns_record_line) - 1 + 16;       /* To hold the IPv6-Address */
 446
 447   struct answer_packet_list *answer =
 448       GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
 449   memset (answer, 0, len + 2 * sizeof (struct answer_packet_list *));
 450
 451   answer->pkt.hdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_DNS_LOCAL_RESPONSE_DNS);
 452   answer->pkt.hdr.size = htons (len);
 453
 454   struct dns_pkt_parsed *pdns = parse_dns_packet (dns);
 455
 456   if (ntohs (pdns->s.ancount) < 1)
 457   {
 458     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Answer only contains %d answers.\n",
 459                 ntohs (pdns->s.ancount));
 460     free_parsed_dns_packet (pdns);
 461     return GNUNET_OK;
 462   }
 463
 464   answer->pkt.addrsize = ntohs (pdns->answers[0]->data_len);
 465   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "The first answer has the addrlen %d\n",
 466               answer->pkt.addrsize);
 467   memcpy (answer->pkt.addr, pdns->answers[0]->data,
 468           ntohs (pdns->answers[0]->data_len));
 469
 470   answer->pkt.from = query_states[dns->s.id].remote_ip;
 471
 472   answer->pkt.to = query_states[dns->s.id].local_ip;
 473   answer->pkt.dst_port = query_states[dns->s.id].local_port;
 474
 475   struct dns_pkt *dpkt = (struct dns_pkt *) answer->pkt.data;
 476
 477   dpkt->s.id = dns->s.id;
 478   dpkt->s.aa = 1;
 479   dpkt->s.qr = 1;
 480   dpkt->s.ra = 1;
 481   dpkt->s.qdcount = htons (1);
 482   dpkt->s.ancount = htons (1);
 483
 484   memcpy (dpkt->data, query_states[dns->s.id].name,
 485           query_states[dns->s.id].namelen);
 486   GNUNET_free (query_states[dns->s.id].name);
 487   query_states[dns->s.id].name = NULL;
 488
 489   struct dns_query_line *dque =
 490       (struct dns_query_line *) (dpkt->data +
 491                                  (query_states[dns->s.id].namelen));
 492
 493   struct dns_record_line *drec_data =
 494       (struct dns_record_line *) (dpkt->data +
 495                                   (query_states[dns->s.id].namelen) +
 496                                   sizeof (struct dns_query_line) + 2);
 497   if (16 == answer->pkt.addrsize)
 498   {
 499     answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REMOTE_AAAA;
 500     dque->type = htons (28);    /* AAAA */
 501     drec_data->type = htons (28);       /* AAAA */
 502     drec_data->data_len = htons (16);
 503   }
 504   else
 505   {
 506     answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REMOTE_A;
 507     dque->type = htons (1);     /* A */
 508     drec_data->type = htons (1);        /* A */
 509     drec_data->data_len = htons (4);
 510   }
 511   dque->class = htons (1);      /* IN */
 512
 513   char *anname =
 514       (char *) (dpkt->data + (query_states[dns->s.id].namelen) +
 515                 sizeof (struct dns_query_line));
 516   memcpy (anname, "\xc0\x0c", 2);
 517   drec_data->class = htons (1); /* IN */
 518
 519   drec_data->ttl = pdns->answers[0]->ttl;
 520
 521   /* Calculate at which offset in the packet the IPv6-Address belongs, it is
 522    * filled in by the daemon-vpn */
 523   answer->pkt.addroffset =
 524       htons ((unsigned short) ((unsigned long) (&drec_data->data) -
 525                                (unsigned long) (&answer->pkt)));
 526
 527   GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
 528
 529   GNUNET_SERVER_notify_transmit_ready (query_states[dns->s.id].client,
 530                                        len,
 531                                        GNUNET_TIME_UNIT_FOREVER_REL,
 532                                        &send_answer,
 533                                        query_states[dns->s.id].client);
 534
 535   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 536               "Sent answer of length %d on to client, addroffset = %d\n", len,
 537               answer->pkt.addroffset);
 538
 539   free_parsed_dns_packet (pdns);
 540   return GNUNET_OK;
 541 }
 542
 543
 544 static void
 545 send_rev_query (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 546 {
 547   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
 548     return;
 549
 550   struct dns_pkt_parsed *pdns = (struct dns_pkt_parsed *) cls;
 551
 552   unsigned short id = pdns->s.id;
 553
 554   free_parsed_dns_packet (pdns);
 555
 556   if (query_states[id].valid != GNUNET_YES)
 557     return;
 558   query_states[id].valid = GNUNET_NO;
 559
 560   GNUNET_assert (query_states[id].namelen == 74);
 561
 562   size_t len = sizeof (struct answer_packet) - 1 + sizeof (struct dns_static) + 74      /* this is the length of a reverse ipv6-lookup */
 563       + sizeof (struct dns_query_line) + 2      /* To hold the pointer (as defined in RFC1035) to the name */
 564       + sizeof (struct dns_record_line) - 1
 565       - 2 /* We do not know the lenght of the answer yet */ ;
 566
 567   struct answer_packet_list *answer =
 568       GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
 569   memset (answer, 0, len + 2 * sizeof (struct answer_packet_list *));
 570
 571   answer->pkt.hdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_DNS_LOCAL_RESPONSE_DNS);
 572   answer->pkt.hdr.size = htons (len);
 573   answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REV;
 574
 575   answer->pkt.from = query_states[id].remote_ip;
 576
 577   answer->pkt.to = query_states[id].local_ip;
 578   answer->pkt.dst_port = query_states[id].local_port;
 579
 580   struct dns_pkt *dpkt = (struct dns_pkt *) answer->pkt.data;
 581
 582   dpkt->s.id = id;
 583   dpkt->s.aa = 1;
 584   dpkt->s.qr = 1;
 585   dpkt->s.ra = 1;
 586   dpkt->s.qdcount = htons (1);
 587   dpkt->s.ancount = htons (1);
 588
 589   memcpy (dpkt->data, query_states[id].name, query_states[id].namelen);
 590   GNUNET_free (query_states[id].name);
 591
 592   struct dns_query_line *dque =
 593       (struct dns_query_line *) (dpkt->data + (query_states[id].namelen));
 594   dque->type = htons (12);      /* PTR */
 595   dque->class = htons (1);      /* IN */
 596
 597   char *anname =
 598       (char *) (dpkt->data + (query_states[id].namelen) +
 599                 sizeof (struct dns_query_line));
 600   memcpy (anname, "\xc0\x0c", 2);
 601
 602   struct dns_record_line *drec_data =
 603       (struct dns_record_line *) (dpkt->data + (query_states[id].namelen) +
 604                                   sizeof (struct dns_query_line) + 2);
 605   drec_data->type = htons (12); /* AAAA */
 606   drec_data->class = htons (1); /* IN */
 607   /* FIXME: read the TTL from block:
 608    * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
 609    *
 610    * But how to get the seconds out of this?
 611    */
 612   drec_data->ttl = htonl (3600);
 613
 614   /* Calculate at which offset in the packet the length of the name and the
 615    * name, it is filled in by the daemon-vpn */
 616   answer->pkt.addroffset =
 617       htons ((unsigned short) ((unsigned long) (&drec_data->data_len) -
 618                                (unsigned long) (&answer->pkt)));
 619
 620   GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
 621
 622   GNUNET_SERVER_notify_transmit_ready (query_states[id].client,
 623                                        len,
 624                                        GNUNET_TIME_UNIT_FOREVER_REL,
 625                                        &send_answer, query_states[id].client);
 626 }
 627
 628 /**
 629  * Receive a block from the dht.
 630  */
 631 static void
 632 receive_dht (void *cls,
 633              struct GNUNET_TIME_Absolute exp __attribute__ ((unused)),
 634              const GNUNET_HashCode * key __attribute__ ((unused)),
 635              const struct GNUNET_PeerIdentity *const *get_path
 636              __attribute__ ((unused)),
 637              const struct GNUNET_PeerIdentity *const *put_path
 638              __attribute__ ((unused)), enum GNUNET_BLOCK_Type type, size_t size,
 639              const void *data)
 640 {
 641
 642   unsigned short id = ((struct receive_dht_cls *) cls)->id;
 643   struct GNUNET_DHT_GetHandle *handle =
 644       ((struct receive_dht_cls *) cls)->handle;
 645   GNUNET_free (cls);
 646
 647   GNUNET_assert (type == GNUNET_BLOCK_TYPE_DNS);
 648
 649   /* If no query with this id is pending, ignore the block */
 650   if (query_states[id].valid != GNUNET_YES)
 651     return;
 652   query_states[id].valid = GNUNET_NO;
 653
 654   const struct GNUNET_DNS_Record *rec = data;
 655
 656   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 657               "Got block of size %d, peer: %08x, desc: %08x\n",
 658               size,
 659               *((unsigned int *) &rec->peer),
 660               *((unsigned int *) &rec->service_descriptor));
 661
 662   size_t len = sizeof (struct answer_packet) - 1 + sizeof (struct dns_static) + query_states[id].namelen + sizeof (struct dns_query_line) + 2   /* To hold the pointer (as defined in RFC1035) to the name */
 663       + sizeof (struct dns_record_line) - 1 + 16;       /* To hold the IPv6-Address */
 664
 665   struct answer_packet_list *answer =
 666       GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
 667   memset (answer, 0, len + 2 * sizeof (struct answer_packet_list *));
 668
 669   answer->pkt.hdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_DNS_LOCAL_RESPONSE_DNS);
 670   answer->pkt.hdr.size = htons (len);
 671   answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_SERVICE;
 672
 673   GNUNET_CRYPTO_hash (&rec->peer,
 674                       sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
 675                       &answer->pkt.service_descr.peer);
 676
 677   memcpy (&answer->pkt.service_descr.service_descriptor,
 678           &rec->service_descriptor, sizeof (GNUNET_HashCode));
 679   memcpy (&answer->pkt.service_descr.service_type,
 680           &rec->service_type, sizeof (answer->pkt.service_descr.service_type));
 681   memcpy (&answer->pkt.service_descr.ports, &rec->ports,
 682           sizeof (answer->pkt.service_descr.ports));
 683
 684   answer->pkt.from = query_states[id].remote_ip;
 685
 686   answer->pkt.to = query_states[id].local_ip;
 687   answer->pkt.dst_port = query_states[id].local_port;
 688
 689   struct dns_pkt *dpkt = (struct dns_pkt *) answer->pkt.data;
 690
 691   dpkt->s.id = id;
 692   dpkt->s.aa = 1;
 693   dpkt->s.qr = 1;
 694   dpkt->s.ra = 1;
 695   dpkt->s.qdcount = htons (1);
 696   dpkt->s.ancount = htons (1);
 697
 698   memcpy (dpkt->data, query_states[id].name, query_states[id].namelen);
 699   GNUNET_free (query_states[id].name);
 700
 701   struct dns_query_line *dque =
 702       (struct dns_query_line *) (dpkt->data + (query_states[id].namelen));
 703   dque->type = htons (28);      /* AAAA */
 704   dque->class = htons (1);      /* IN */
 705
 706   char *anname =
 707       (char *) (dpkt->data + (query_states[id].namelen) +
 708                 sizeof (struct dns_query_line));
 709   memcpy (anname, "\xc0\x0c", 2);
 710
 711   struct dns_record_line *drec_data =
 712       (struct dns_record_line *) (dpkt->data + (query_states[id].namelen) +
 713                                   sizeof (struct dns_query_line) + 2);
 714   drec_data->type = htons (28); /* AAAA */
 715   drec_data->class = htons (1); /* IN */
 716
 717   /* FIXME: read the TTL from block:
 718    * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
 719    *
 720    * But how to get the seconds out of this?
 721    */
 722   drec_data->ttl = htonl (3600);
 723   drec_data->data_len = htons (16);
 724
 725   /* Calculate at which offset in the packet the IPv6-Address belongs, it is
 726    * filled in by the daemon-vpn */
 727   answer->pkt.addroffset =
 728       htons ((unsigned short) ((unsigned long) (&drec_data->data) -
 729                                (unsigned long) (&answer->pkt)));
 730
 731   GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
 732
 733   GNUNET_SERVER_notify_transmit_ready (query_states[id].client,
 734                                        len,
 735                                        GNUNET_TIME_UNIT_FOREVER_REL,
 736                                        &send_answer, query_states[id].client);
 737
 738   GNUNET_DHT_get_stop (handle);
 739 }
 740
 741 /**
 742  * This receives a GNUNET_MESSAGE_TYPE_REHIJACK and rehijacks the DNS
 743  */
 744 static void
 745 rehijack (void *cls __attribute__ ((unused)),
 746           struct GNUNET_SERVER_Client *client,
 747           const struct GNUNET_MessageHeader *message __attribute__ ((unused)))
 748 {
 749   unhijack (dnsoutport);
 750   GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
 751
 752   GNUNET_SERVER_receive_done (client, GNUNET_OK);
 753 }
 754
 755 /**
 756  * This receives the dns-payload from the daemon-vpn and sends it on over the udp-socket
 757  */
 758 static void
 759 receive_query (void *cls __attribute__ ((unused)),
 760                struct GNUNET_SERVER_Client *client,
 761                const struct GNUNET_MessageHeader *message)
 762 {
 763   struct query_packet *pkt = (struct query_packet *) message;
 764   struct dns_pkt *dns = (struct dns_pkt *) pkt->data;
 765   struct dns_pkt_parsed *pdns = parse_dns_packet (dns);
 766
 767   query_states[dns->s.id].valid = GNUNET_YES;
 768   query_states[dns->s.id].client = client;
 769   query_states[dns->s.id].local_ip = pkt->orig_from;
 770   query_states[dns->s.id].local_port = pkt->src_port;
 771   query_states[dns->s.id].remote_ip = pkt->orig_to;
 772   query_states[dns->s.id].namelen = strlen ((char *) dns->data) + 1;
 773   if (query_states[dns->s.id].name != NULL)
 774     GNUNET_free (query_states[dns->s.id].name);
 775   query_states[dns->s.id].name =
 776       GNUNET_malloc (query_states[dns->s.id].namelen);
 777   memcpy (query_states[dns->s.id].name, dns->data,
 778           query_states[dns->s.id].namelen);
 779
 780   /* The query is for a .gnunet-address */
 781   if (pdns->queries[0]->namelen > 9 &&
 782       0 == strncmp (pdns->queries[0]->name + (pdns->queries[0]->namelen - 9),
 783                     ".gnunet.", 9))
 784   {
 785     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Query for .gnunet!\n");
 786     GNUNET_HashCode key;
 787
 788     GNUNET_CRYPTO_hash (pdns->queries[0]->name, pdns->queries[0]->namelen,
 789                         &key);
 790
 791     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 792                 "Getting with key %08x, len is %d\n",
 793                 *((unsigned int *) &key), pdns->queries[0]->namelen);
 794
 795     struct receive_dht_cls *cls =
 796         GNUNET_malloc (sizeof (struct receive_dht_cls));
 797     cls->id = dns->s.id;
 798
 799     cls->handle = GNUNET_DHT_get_start (dht,
 800                                         GNUNET_TIME_UNIT_MINUTES,
 801                                         GNUNET_BLOCK_TYPE_DNS,
 802                                         &key,
 803                                         DEFAULT_GET_REPLICATION,
 804                                         GNUNET_DHT_RO_NONE,
 805                                         NULL, 0, NULL, 0, receive_dht, cls);
 806
 807     goto outfree;
 808   }
 809
 810   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Query for '%s'; namelen=%d\n",
 811               pdns->queries[0]->name, pdns->queries[0]->namelen);
 812
 813   /* This is a PTR-Query. Check if it is for "our" network */
 814   if (htons (pdns->queries[0]->qtype) == 12 && 74 == pdns->queries[0]->namelen)
 815   {
 816     char *ipv6addr;
 817     char ipv6[16];
 818     char ipv6rev[74] =
 819         "X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.ip6.arpa.";
 820     unsigned int i;
 821     unsigned long long ipv6prefix;
 822     unsigned int comparelen;
 823
 824     GNUNET_assert (GNUNET_OK ==
 825                    GNUNET_CONFIGURATION_get_value_string (cfg, "vpn",
 826                                                           "IPV6ADDR",
 827                                                           &ipv6addr));
 828     inet_pton (AF_INET6, ipv6addr, ipv6);
 829     GNUNET_free (ipv6addr);
 830
 831     GNUNET_assert (GNUNET_OK ==
 832                    GNUNET_CONFIGURATION_get_value_number (cfg, "vpn",
 833                                                           "IPV6PREFIX",
 834                                                           &ipv6prefix));
 835     GNUNET_assert (ipv6prefix < 127);
 836     ipv6prefix = (ipv6prefix + 7) / 8;
 837
 838     for (i = ipv6prefix; i < 16; i++)
 839       ipv6[i] = 0;
 840
 841     for (i = 0; i < 16; i++)
 842     {
 843       unsigned char c1 = ipv6[i] >> 4;
 844       unsigned char c2 = ipv6[i] & 0xf;
 845
 846       if (c1 <= 9)
 847         ipv6rev[62 - (4 * i)] = c1 + '0';
 848       else
 849         ipv6rev[62 - (4 * i)] = c1 + 87;        /* 87 is the difference between 'a' and 10 */
 850
 851       if (c2 <= 9)
 852         ipv6rev[62 - ((4 * i) + 2)] = c2 + '0';
 853       else
 854         ipv6rev[62 - ((4 * i) + 2)] = c2 + 87;
 855     }
 856     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "My network is %s'.\n", ipv6rev);
 857     comparelen = 10 + 4 * ipv6prefix;
 858     if (0 ==
 859         strncmp (pdns->queries[0]->name +
 860                  (pdns->queries[0]->namelen - comparelen),
 861                  ipv6rev + (74 - comparelen), comparelen))
 862     {
 863       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Reverse-Query for .gnunet!\n");
 864
 865       GNUNET_SCHEDULER_add_now (send_rev_query, pdns);
 866
 867       goto out;
 868     }
 869   }
 870
 871   char *virt_dns;
 872   unsigned int virt_dns_bytes;
 873
 874   if (GNUNET_SYSERR ==
 875       GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS", &virt_dns))
 876   {
 877     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 878                 "No entry 'VIRTDNS' in configuration!\n");
 879     exit (1);
 880   }
 881
 882   if (1 != inet_pton (AF_INET, virt_dns, &virt_dns_bytes))
 883   {
 884     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 885                 "Error parsing 'VIRTDNS': %s; %m!\n", virt_dns);
 886     exit (1);
 887   }
 888
 889   GNUNET_free (virt_dns);
 890
 891   if (virt_dns_bytes == pkt->orig_to)
 892   {
 893     /* This is a packet that was sent directly to the virtual dns-server
 894      *
 895      * This means we have to send this query over gnunet
 896      */
 897
 898     size_t size =
 899         sizeof (struct GNUNET_MESH_Tunnel *) +
 900         sizeof (struct GNUNET_MessageHeader) + (ntohs (message->size) -
 901                                                 sizeof (struct query_packet) +
 902                                                 1);
 903     struct tunnel_cls *cls_ = GNUNET_malloc (size);
 904
 905     cls_->hdr.size = size - sizeof (struct GNUNET_MESH_Tunnel *);
 906
 907     cls_->hdr.type = ntohs (GNUNET_MESSAGE_TYPE_VPN_REMOTE_QUERY_DNS);
 908     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "size: %d\n", size);
 909
 910     memcpy (&cls_->dns, dns,
 911             cls_->hdr.size - sizeof (struct GNUNET_MessageHeader));
 912     GNUNET_SCHEDULER_add_now (send_mesh_query, cls_);
 913
 914     goto outfree;
 915   }
 916
 917
 918   /* The query should be sent to the network */
 919
 920   struct sockaddr_in dest;
 921
 922   memset (&dest, 0, sizeof dest);
 923   dest.sin_port = htons (53);
 924   dest.sin_addr.s_addr = pkt->orig_to;
 925
 926   GNUNET_NETWORK_socket_sendto (dnsout,
 927                                 dns,
 928                                 ntohs (pkt->hdr.size) -
 929                                 sizeof (struct query_packet) + 1,
 930                                 (struct sockaddr *) &dest, sizeof dest);
 931
 932 outfree:
 933   free_parsed_dns_packet (pdns);
 934   pdns = NULL;
 935 out:
 936   GNUNET_SERVER_receive_done (client, GNUNET_OK);
 937 }
 938
 939 static void read_response (void *cls,
 940                            const struct GNUNET_SCHEDULER_TaskContext *tc);
 941
 942 static int
 943 open_port ()
 944 {
 945   struct sockaddr_in addr;
 946
 947   dnsout = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
 948   if (dnsout == NULL)
 949     return GNUNET_SYSERR;
 950   memset (&addr, 0, sizeof (struct sockaddr_in));
 951
 952   addr.sin_family = AF_INET;
 953   int err = GNUNET_NETWORK_socket_bind (dnsout,
 954                                         (struct sockaddr *) &addr,
 955                                         sizeof (struct sockaddr_in));
 956
 957   if (err != GNUNET_OK)
 958   {
 959     GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not bind a port: %m\n");
 960     return GNUNET_SYSERR;
 961   }
 962
 963   /* Read the port we bound to */
 964   socklen_t addrlen = sizeof (struct sockaddr_in);
 965
 966   err = getsockname (GNUNET_NETWORK_get_fd (dnsout),
 967                      (struct sockaddr *) &addr, &addrlen);
 968
 969   dnsoutport = htons (addr.sin_port);
 970
 971   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Bound to port %d.\n", dnsoutport);
 972
 973   GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, dnsout,
 974                                  &read_response, NULL);
 975
 976   return GNUNET_YES;
 977 }
 978
 979 /**
 980  * Read a response-packet of the UDP-Socket
 981  */
 982 static void
 983 read_response (void *cls
 984                __attribute__ ((unused)),
 985                const struct GNUNET_SCHEDULER_TaskContext *tc)
 986 {
 987   struct sockaddr_in addr;
 988   socklen_t addrlen = sizeof (addr);
 989   int r;
 990   int len;
 991
 992   if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
 993     return;
 994
 995   memset (&addr, 0, sizeof addr);
 996
 997 #ifndef MINGW
 998   if (0 != ioctl (GNUNET_NETWORK_get_fd (dnsout), FIONREAD, &len))
 999   {
1000     unhijack (dnsoutport);
1001     if (GNUNET_YES == open_port ())
1002       GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
1003     return;
1004   }
1005 #else
1006   /* port the code above? */
1007   len = 65536;
1008 #endif
1009   {
1010     unsigned char buf[len];
1011     struct dns_pkt *dns = (struct dns_pkt *) buf;
1012
1013     r = GNUNET_NETWORK_socket_recvfrom (dnsout,
1014                                         buf,
1015                                         sizeof (buf),
1016                                         (struct sockaddr *) &addr, &addrlen);
1017
1018     if (r < 0)
1019     {
1020       unhijack (dnsoutport);
1021       if (GNUNET_YES == open_port ())
1022         GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
1023       return;
1024     }
1025
1026     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Answer to query %d\n",
1027                 ntohs (dns->s.id));
1028
1029     if (query_states[dns->s.id].valid == GNUNET_YES)
1030     {
1031       if (query_states[dns->s.id].tunnel != NULL)
1032       {
1033         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1034                     "Answer to query %d for a remote peer!\n",
1035                     ntohs (dns->s.id));
1036         /* This response should go through a tunnel */
1037         uint32_t *c =
1038             GNUNET_malloc (4 + sizeof (struct GNUNET_MESH_Tunnel *) + r);
1039         *c = r;
1040         struct GNUNET_MESH_Tunnel **t = (struct GNUNET_MESH_Tunnel **) (c + 1);
1041
1042         *t = query_states[dns->s.id].tunnel;
1043         memcpy (t + 1, dns, r);
1044         if (NULL ==
1045             GNUNET_MESH_tunnel_get_data (query_states[dns->s.id].tunnel))
1046         {
1047           struct GNUNET_MESH_TransmitHandle *th =
1048               GNUNET_MESH_notify_transmit_ready (query_states[dns->s.id].tunnel,
1049                                                  GNUNET_YES,
1050                                                  32,
1051                                                  GNUNET_TIME_UNIT_MINUTES,
1052                                                  NULL,
1053                                                  r +
1054                                                  sizeof (struct
1055                                                          GNUNET_MessageHeader),
1056                                                  mesh_send_response, c);
1057
1058           GNUNET_MESH_tunnel_set_data (query_states[dns->s.id].tunnel, th);
1059         }
1060         else
1061         {
1062           struct tunnel_notify_queue *head =
1063               GNUNET_MESH_tunnel_get_head (query_states[dns->s.id].tunnel);
1064           struct tunnel_notify_queue *tail =
1065               GNUNET_MESH_tunnel_get_tail (query_states[dns->s.id].tunnel);
1066
1067           struct tunnel_notify_queue *element =
1068               GNUNET_malloc (sizeof (struct tunnel_notify_queue));
1069           element->cls = c;
1070           element->len = r + sizeof (struct GNUNET_MessageHeader);
1071           element->cb = mesh_send_response;
1072
1073           GNUNET_CONTAINER_DLL_insert_tail (head, tail, element);
1074           GNUNET_MESH_tunnel_set_head (query_states[dns->s.id].tunnel, head);
1075           GNUNET_MESH_tunnel_set_tail (query_states[dns->s.id].tunnel, tail);
1076         }
1077       }
1078       else
1079       {
1080         query_states[dns->s.id].valid = GNUNET_NO;
1081
1082         size_t len = sizeof (struct answer_packet) + r - 1;     /* 1 for the unsigned char data[1]; */
1083         struct answer_packet_list *answer =
1084             GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
1085         answer->pkt.hdr.type =
1086             htons (GNUNET_MESSAGE_TYPE_VPN_DNS_LOCAL_RESPONSE_DNS);
1087         answer->pkt.hdr.size = htons (len);
1088         answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_IP;
1089         answer->pkt.from = addr.sin_addr.s_addr;
1090         answer->pkt.to = query_states[dns->s.id].local_ip;
1091         answer->pkt.dst_port = query_states[dns->s.id].local_port;
1092         memcpy (answer->pkt.data, buf, r);
1093
1094         GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
1095
1096         GNUNET_SERVER_notify_transmit_ready (query_states
1097                                              [dns->s.id].client, len,
1098                                              GNUNET_TIME_UNIT_FOREVER_REL,
1099                                              &send_answer,
1100                                              query_states[dns->s.id].client);
1101       }
1102     }
1103   }
1104   GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
1105                                  dnsout, &read_response, NULL);
1106 }
1107
1108
1109 /**
1110  * Task run during shutdown.
1111  *
1112  * @param cls unused
1113  * @param tc unused
1114  */
1115 static void
1116 cleanup_task (void *cls __attribute__ ((unused)),
1117               const struct GNUNET_SCHEDULER_TaskContext *tc)
1118 {
1119   GNUNET_assert (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
1120
1121   unhijack (dnsoutport);
1122   GNUNET_DHT_disconnect (dht);
1123   GNUNET_MESH_disconnect (mesh_handle);
1124 }
1125
1126 /**
1127  * @brief Create a port-map from udp and tcp redirects
1128  *
1129  * @param udp_redirects
1130  * @param tcp_redirects
1131  *
1132  * @return
1133  */
1134 uint64_t
1135 get_port_from_redirects (const char *udp_redirects, const char *tcp_redirects)
1136 {
1137   uint64_t ret = 0;
1138   char *cpy, *hostname, *redirect;
1139   int local_port, count = 0;
1140
1141   if (NULL != udp_redirects)
1142   {
1143     cpy = GNUNET_strdup (udp_redirects);
1144     for (redirect = strtok (cpy, " "); redirect != NULL;
1145          redirect = strtok (NULL, " "))
1146     {
1147       if (NULL == (hostname = strstr (redirect, ":")))
1148       {
1149         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1150                     "Warning: option %s is not formatted correctly!\n",
1151                     redirect);
1152         continue;
1153       }
1154       hostname[0] = '\0';
1155       local_port = atoi (redirect);
1156       if (!((local_port > 0) && (local_port < 65536)))
1157         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1158                     "Warning: %s is not a correct port.", redirect);
1159
1160       ret |= (0xFFFF & htons (local_port));
1161       ret <<= 16;
1162       count++;
1163
1164       if (count > 4)
1165       {
1166         ret = 0;
1167         goto out;
1168       }
1169     }
1170     GNUNET_free (cpy);
1171     cpy = NULL;
1172   }
1173
1174   if (NULL != tcp_redirects)
1175   {
1176     cpy = GNUNET_strdup (tcp_redirects);
1177     for (redirect = strtok (cpy, " "); redirect != NULL;
1178          redirect = strtok (NULL, " "))
1179     {
1180       if (NULL == (hostname = strstr (redirect, ":")))
1181       {
1182         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1183                     "Warning: option %s is not formatted correctly!\n",
1184                     redirect);
1185         continue;
1186       }
1187       hostname[0] = '\0';
1188       local_port = atoi (redirect);
1189       if (!((local_port > 0) && (local_port < 65536)))
1190         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1191                     "Warning: %s is not a correct port.", redirect);
1192
1193       ret |= (0xFFFF & htons (local_port));
1194       ret <<= 16;
1195       count++;
1196
1197       if (count > 4)
1198       {
1199         ret = 0;
1200         goto out;
1201       }
1202     }
1203     GNUNET_free (cpy);
1204     cpy = NULL;
1205   }
1206
1207 out:
1208   if (NULL != cpy)
1209     GNUNET_free (cpy);
1210   return ret;
1211 }
1212
1213 void
1214 publish_name (const char *name, uint64_t ports, uint32_t service_type,
1215               struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key)
1216 {
1217   size_t size = sizeof (struct GNUNET_DNS_Record);
1218   struct GNUNET_DNS_Record data;
1219
1220   memset (&data, 0, size);
1221
1222   data.purpose.size = htonl (size - sizeof (struct GNUNET_CRYPTO_RsaSignature));
1223   data.purpose.purpose = GNUNET_SIGNATURE_PURPOSE_DNS_RECORD;
1224
1225   GNUNET_CRYPTO_hash (name, strlen (name) + 1, &data.service_descriptor);
1226   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Store with key1 %x\n",
1227               *((unsigned long long *) &data.service_descriptor));
1228
1229   data.service_type = service_type;
1230   data.ports = ports;
1231
1232   GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &data.peer);
1233
1234   data.expiration_time =
1235       GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_multiply
1236                                         (GNUNET_TIME_UNIT_HOURS, 2));
1237
1238   /* Sign the block */
1239   if (GNUNET_OK != GNUNET_CRYPTO_rsa_sign (my_private_key,
1240                                            &data.purpose, &data.signature))
1241   {
1242     GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not sign DNS_Record\n");
1243     return;
1244   }
1245
1246   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1247               "Putting with key %08x, size = %d\n",
1248               *((unsigned int *) &data.service_descriptor), size);
1249
1250   GNUNET_DHT_put (dht,
1251                   &data.service_descriptor,
1252                   DEFAULT_PUT_REPLICATION,
1253                   GNUNET_DHT_RO_NONE,
1254                   GNUNET_BLOCK_TYPE_DNS,
1255                   size,
1256                   (char *) &data,
1257                   GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_HOURS),
1258                   GNUNET_TIME_UNIT_MINUTES, NULL, NULL);
1259 }
1260
1261 /**
1262  * @brief Publishes the record defined by the section section
1263  *
1264  * @param cls closure
1265  * @param section the current section
1266  */
1267 void
1268 publish_iterate (void *cls __attribute__ ((unused)), const char *section)
1269 {
1270   if ((strlen (section) < 8) ||
1271       (0 != strcmp (".gnunet.", section + (strlen (section) - 8))))
1272     return;
1273
1274   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Parsing dns-name %s\n", section);
1275
1276   char *udp_redirects, *tcp_redirects, *alternative_names, *alternative_name,
1277       *keyfile;
1278
1279   GNUNET_CONFIGURATION_get_value_string (cfg, section,
1280                                          "UDP_REDIRECTS", &udp_redirects);
1281   GNUNET_CONFIGURATION_get_value_string (cfg, section, "TCP_REDIRECTS",
1282                                          &tcp_redirects);
1283
1284   if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_filename (cfg, "GNUNETD",
1285                                                             "HOSTKEY",
1286                                                             &keyfile))
1287   {
1288     GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not read keyfile-value\n");
1289     if (keyfile != NULL)
1290       GNUNET_free (keyfile);
1291     return;
1292   }
1293
1294   struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key =
1295       GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
1296   GNUNET_free (keyfile);
1297   GNUNET_assert (my_private_key != NULL);
1298
1299   uint64_t ports = get_port_from_redirects (udp_redirects, tcp_redirects);
1300   uint32_t service_type = 0;
1301
1302   if (NULL != udp_redirects)
1303     service_type = GNUNET_DNS_SERVICE_TYPE_UDP;
1304
1305   if (NULL != tcp_redirects)
1306     service_type |= GNUNET_DNS_SERVICE_TYPE_TCP;
1307
1308   service_type = htonl (service_type);
1309
1310
1311   publish_name (section, ports, service_type, my_private_key);
1312
1313   GNUNET_CONFIGURATION_get_value_string (cfg, section,
1314                                          "ALTERNATIVE_NAMES",
1315                                          &alternative_names);
1316   for (alternative_name = strtok (alternative_names, " ");
1317        alternative_name != NULL; alternative_name = strtok (NULL, " "))
1318   {
1319     char *altname =
1320         alloca (strlen (alternative_name) + strlen (section) + 1 + 1);
1321     strcpy (altname, alternative_name);
1322     strcpy (altname + strlen (alternative_name) + 1, section);
1323     altname[strlen (alternative_name)] = '.';
1324
1325     publish_name (altname, ports, service_type, my_private_key);
1326   }
1327
1328   GNUNET_free_non_null (alternative_names);
1329   GNUNET_CRYPTO_rsa_key_free (my_private_key);
1330   GNUNET_free_non_null (udp_redirects);
1331   GNUNET_free_non_null (tcp_redirects);
1332 }
1333
1334 /**
1335  * Publish a DNS-record in the DHT.
1336  */
1337 static void
1338 publish_names (void *cls __attribute__ ((unused)),
1339                const struct GNUNET_SCHEDULER_TaskContext *tc)
1340 {
1341   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1342     return;
1343
1344   GNUNET_CONFIGURATION_iterate_sections (cfg, publish_iterate, NULL);
1345
1346   GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_HOURS, publish_names, NULL);
1347 }
1348
1349 /**
1350  * @param cls closure
1351  * @param server the initialized server
1352  * @param cfg_ configuration to use
1353  */
1354 static void
1355 run (void *cls,
1356      struct GNUNET_SERVER_Handle *server,
1357      const struct GNUNET_CONFIGURATION_Handle *cfg_)
1358 {
1359   static const struct GNUNET_SERVER_MessageHandler handlers[] = {
1360     /* callback, cls, type, size */
1361     {&receive_query, NULL, GNUNET_MESSAGE_TYPE_VPN_DNS_LOCAL_QUERY_DNS, 0},
1362     {&rehijack, NULL, GNUNET_MESSAGE_TYPE_REHIJACK,
1363      sizeof (struct GNUNET_MessageHeader)},
1364     {NULL, NULL, 0, 0}
1365   };
1366
1367   static const struct GNUNET_MESH_MessageHandler mesh_handlers[] = {
1368     {receive_mesh_query, GNUNET_MESSAGE_TYPE_VPN_REMOTE_QUERY_DNS, 0},
1369     {receive_mesh_answer, GNUNET_MESSAGE_TYPE_VPN_REMOTE_ANSWER_DNS, 0},
1370     {NULL, 0, 0}
1371   };
1372
1373   static GNUNET_MESH_ApplicationType apptypes[] = {
1374     GNUNET_APPLICATION_TYPE_END,
1375     GNUNET_APPLICATION_TYPE_END
1376   };
1377
1378
1379   if (GNUNET_YES != open_port ())
1380   {
1381     GNUNET_SCHEDULER_shutdown ();
1382     return;
1383   }
1384
1385   if (GNUNET_YES ==
1386       GNUNET_CONFIGURATION_get_value_yesno (cfg_, "dns", "PROVIDE_EXIT"))
1387     apptypes[0] = GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER;
1388   mesh_handle = GNUNET_MESH_connect (cfg_, NULL, NULL, mesh_handlers, apptypes);
1389
1390   cfg = cfg_;
1391
1392   unsigned int i;
1393
1394   for (i = 0; i < 65536; i++)
1395   {
1396     query_states[i].valid = GNUNET_NO;
1397   }
1398
1399   dht = GNUNET_DHT_connect (cfg, 1024);
1400
1401   GNUNET_SCHEDULER_add_now (publish_names, NULL);
1402
1403   GNUNET_SERVER_add_handlers (server, handlers);
1404   GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
1405                                 &cleanup_task, cls);
1406 }
1407
1408 /**
1409  * The main function for the dns service.
1410  *
1411  * @param argc number of arguments from the command line
1412  * @param argv command line arguments
1413  * @return 0 ok, 1 on error
1414  */
1415 int
1416 main (int argc, char *const *argv)
1417 {
1418   return (GNUNET_OK ==
1419           GNUNET_SERVICE_run (argc,
1420                               argv,
1421                               "dns",
1422                               GNUNET_SERVICE_OPTION_NONE, &run, NULL)) ? 0 : 1;
1423 }