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