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