2 This file is part of GNUnet.
3 (C) 2009 Christian Grothoff (and other contributing authors)
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.
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.
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.
22 * @file vpn/gnunet-service-dns.c
23 * @author Philipp Toelke
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"
44 struct GNUNET_MESH_Handle *mesh_handle;
47 * The tunnel to send queries
49 static struct GNUNET_MESH_Tunnel* dns_tunnel;
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.
55 static struct GNUNET_NETWORK_Handle *dnsout;
58 * The port bound to the socket dnsout
60 static unsigned short dnsoutport;
63 * A handle to the DHT-Service
65 static struct GNUNET_DHT_Handle *dht;
68 * The configuration to use
70 static const struct GNUNET_CONFIGURATION_Handle *cfg;
73 * A list of DNS-Responses that have to be sent to the requesting client
75 static struct answer_packet_list *head;
78 * The tail of the list of DNS-responses
80 static struct answer_packet_list *tail;
83 * A structure containing a mapping from network-byte-ordered DNS-id (16 bit) to
84 * some information needed to handle this query
86 * It currently allocates at least
87 * (1 + machine-width + machine-width + 32 + 32 + 16 + machine-width + 8) * 65536 bit
93 struct GNUNET_SERVER_Client* client;
94 struct GNUNET_MESH_Tunnel *tunnel;
100 } query_states[UINT16_MAX];
103 * A struct used to give more than one value as
104 * closure to receive_dht
106 struct receive_dht_cls {
108 struct GNUNET_DHT_GetHandle* handle;
111 struct tunnel_notify_queue
113 struct tunnel_notify_queue* next;
114 struct tunnel_notify_queue* prev;
117 GNUNET_CONNECTION_TransmitReadyNotify cb;
121 * Hijack all outgoing DNS-Traffic but for traffic leaving "our" port.
124 hijack (void *cls __attribute__((unused)), const struct GNUNET_SCHEDULER_TaskContext *tc)
126 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
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);
138 struct GNUNET_OS_Process *proc;
141 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
144 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
145 "No entry 'VIRTDNS' in configuration!\n");
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,
153 "gnunet-helper-hijack-dns",
155 port_s, virt_dns, NULL)))
156 GNUNET_OS_process_close (proc);
157 GNUNET_free (virt_dns);
161 * Delete the hijacking-routes
164 unhijack (unsigned short port)
168 struct GNUNET_OS_Process *proc;
171 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
174 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
175 "No entry 'VIRTDNS' in configuration!\n");
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,
183 "gnunet-helper-hijack-dns",
185 "-d", port_s, virt_dns, NULL)))
186 GNUNET_OS_process_close (proc);
187 GNUNET_free (virt_dns);
191 * Send the DNS-Response to the client. Gets called via the notify_transmit_ready-
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);
199 GNUNET_assert(len <= size);
201 memcpy(buf, &query->pkt.hdr, len);
203 GNUNET_CONTAINER_DLL_remove (head, tail, query);
207 /* When more data is to be sent, reschedule */
209 GNUNET_SERVER_notify_transmit_ready(cls,
210 ntohs(head->pkt.hdr.size),
211 GNUNET_TIME_UNIT_FOREVER_REL,
219 struct GNUNET_MESH_Tunnel *tunnel GNUNET_PACKED;
220 struct GNUNET_MessageHeader hdr;
224 struct tunnel_cls *remote_pending[UINT16_MAX];
227 mesh_send_response (void *cls, size_t size, void *buf)
229 GNUNET_assert (size >= sizeof (struct GNUNET_MessageHeader));
230 struct GNUNET_MessageHeader *hdr = buf;
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));
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));
241 GNUNET_assert (size >= (*sz + sizeof (struct GNUNET_MessageHeader)));
243 memcpy (hdr + 1, dns, *sz);
245 if (NULL != GNUNET_MESH_tunnel_get_head(*tunnel))
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);
251 GNUNET_CONTAINER_DLL_remove(head, tail, element);
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,
258 GNUNET_TIME_relative_divide
259 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
260 (const struct GNUNET_PeerIdentity *)
262 element->cb, element->cls);
263 /* save the handle */
264 GNUNET_MESH_tunnel_set_data(*tunnel, th);
269 return ntohs (hdr->size);
273 mesh_send (void *cls, size_t size, void *buf)
275 struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
276 GNUNET_MESH_tunnel_set_data(cls_->tunnel, NULL);
278 GNUNET_assert(cls_->hdr.size <= size);
280 size = cls_->hdr.size;
281 cls_->hdr.size = htons(cls_->hdr.size);
283 memcpy(buf, &cls_->hdr, size);
285 if (NULL != GNUNET_MESH_tunnel_get_head(cls_->tunnel))
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);
291 GNUNET_CONTAINER_DLL_remove(head, tail, element);
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,
298 GNUNET_TIME_relative_divide
299 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
300 (const struct GNUNET_PeerIdentity *)
302 element->cb, element->cls);
303 /* save the handle */
304 GNUNET_MESH_tunnel_set_data(cls_->tunnel, th);
312 mesh_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
313 const struct GNUNET_TRANSPORT_ATS_Information *atsi
314 __attribute__ ((unused)))
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));
323 if (NULL == GNUNET_MESH_tunnel_get_data (cls_->tunnel))
325 struct GNUNET_MESH_TransmitHandle *th =
326 GNUNET_MESH_notify_transmit_ready (cls_->tunnel,
329 GNUNET_TIME_UNIT_MINUTES,
335 GNUNET_MESH_tunnel_set_data (cls_->tunnel, th);
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);
342 struct tunnel_notify_queue* element = GNUNET_malloc(sizeof(struct tunnel_notify_queue));
344 element->len = cls_->hdr.size;
345 element->cb = mesh_send;
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);
355 send_mesh_query (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
357 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
360 struct tunnel_cls *cls_ = (struct tunnel_cls*)cls;
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,
369 cls_->tunnel = dns_tunnel;
370 remote_pending[cls_->dns.s.id] = cls_;
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)))
381 struct dns_pkt *dns = (struct dns_pkt*)(message + 1);
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);
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;
393 GNUNET_NETWORK_socket_sendto(dnsout,
395 ntohs(message->size) - sizeof(struct GNUNET_MessageHeader),
396 (struct sockaddr*) &dest,
399 return GNUNET_SYSERR;
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)))
410 /* TODo: size check */
411 struct dns_pkt *dns = (struct dns_pkt *) (message + 1);
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)
418 GNUNET_free(remote_pending[dns->s.id]);
419 remote_pending[dns->s.id] = NULL;
421 if (query_states[dns->s.id].valid != GNUNET_YES)
422 return GNUNET_SYSERR;
423 query_states[dns->s.id].valid = GNUNET_NO;
425 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Received answer from peer %s, dns-id %d\n", GNUNET_i2s(sender), ntohs(dns->s.id));
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 */
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 *));
434 answer->pkt.hdr.type = htons (GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
435 answer->pkt.hdr.size = htons (len);
437 struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
439 if (ntohs(pdns->s.ancount) < 1)
441 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer only contains %d answers.\n", ntohs(pdns->s.ancount));
442 free_parsed_dns_packet(pdns);
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));
450 answer->pkt.from = query_states[dns->s.id].remote_ip;
452 answer->pkt.to = query_states[dns->s.id].local_ip;
453 answer->pkt.dst_port = query_states[dns->s.id].local_port;
455 struct dns_pkt *dpkt = (struct dns_pkt *) answer->pkt.data;
457 dpkt->s.id = dns->s.id;
461 dpkt->s.qdcount = htons (1);
462 dpkt->s.ancount = htons (1);
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);
468 struct dns_query_line *dque =
469 (struct dns_query_line *) (dpkt->data +
470 (query_states[dns->s.id].namelen));
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)
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);
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);
490 dque->class = htons (1); /* IN */
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 */
498 drec_data->ttl = pdns->answers[0]->ttl;
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)));
506 GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
508 GNUNET_SERVER_notify_transmit_ready (query_states[dns->s.id].client,
510 GNUNET_TIME_UNIT_FOREVER_REL,
512 query_states[dns->s.id].client);
514 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sent answer of length %d on to client, addroffset = %d\n", len, answer->pkt.addroffset);
516 free_parsed_dns_packet(pdns);
522 send_rev_query(void * cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
523 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
526 struct dns_pkt_parsed* pdns = (struct dns_pkt_parsed*) cls;
528 unsigned short id = pdns->s.id;
530 free_parsed_dns_packet(pdns);
532 if (query_states[id].valid != GNUNET_YES) return;
533 query_states[id].valid = GNUNET_NO;
535 GNUNET_assert(query_states[id].namelen == 74);
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*/;
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*));
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;
552 answer->pkt.from = query_states[id].remote_ip;
554 answer->pkt.to = query_states[id].local_ip;
555 answer->pkt.dst_port = query_states[id].local_port;
557 struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
563 dpkt->s.qdcount = htons(1);
564 dpkt->s.ancount = htons(1);
566 memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
567 GNUNET_free(query_states[id].name);
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 */
573 char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
574 memcpy(anname, "\xc0\x0c", 2);
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)
582 * But how to get the seconds out of this?
584 drec_data->ttl = htonl(3600);
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)));
590 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
592 GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
594 GNUNET_TIME_UNIT_FOREVER_REL,
596 query_states[id].client);
600 * Receive a block from the dht.
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,
612 unsigned short id = ((struct receive_dht_cls*)cls)->id;
613 struct GNUNET_DHT_GetHandle* handle = ((struct receive_dht_cls*)cls)->handle;
616 GNUNET_assert(type == GNUNET_BLOCK_TYPE_DNS);
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;
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",
626 *((unsigned int*)&rec->peer),
627 *((unsigned int*)&rec->service_descriptor));
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 */
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*));
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;
644 GNUNET_CRYPTO_hash(&rec->peer,
645 sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
646 &answer->pkt.service_descr.peer);
648 memcpy(&answer->pkt.service_descr.service_descriptor,
649 &rec->service_descriptor,
650 sizeof(GNUNET_HashCode));
651 memcpy(&answer->pkt.service_descr.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));
656 answer->pkt.from = query_states[id].remote_ip;
658 answer->pkt.to = query_states[id].local_ip;
659 answer->pkt.dst_port = query_states[id].local_port;
661 struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
667 dpkt->s.qdcount = htons(1);
668 dpkt->s.ancount = htons(1);
670 memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
671 GNUNET_free(query_states[id].name);
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 */
677 char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
678 memcpy(anname, "\xc0\x0c", 2);
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 */
684 /* FIXME: read the TTL from block:
685 * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
687 * But how to get the seconds out of this?
689 drec_data->ttl = htonl(3600);
690 drec_data->data_len = htons(16);
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)));
696 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
698 GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
700 GNUNET_TIME_UNIT_FOREVER_REL,
702 query_states[id].client);
704 GNUNET_DHT_get_stop(handle);
708 * This receives a GNUNET_MESSAGE_TYPE_REHIJACK and rehijacks the DNS
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);
717 GNUNET_SERVER_receive_done(client, GNUNET_OK);
721 * This receives the dns-payload from the daemon-vpn and sends it on over the udp-socket
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);
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);
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))
744 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for .gnunet!\n");
746 GNUNET_CRYPTO_hash(pdns->queries[0]->name, pdns->queries[0]->namelen, &key);
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);
753 struct receive_dht_cls* cls = GNUNET_malloc(sizeof(struct receive_dht_cls));
756 cls->handle = GNUNET_DHT_get_start(dht,
757 GNUNET_TIME_UNIT_MINUTES,
758 GNUNET_BLOCK_TYPE_DNS,
760 DEFAULT_GET_REPLICATION,
772 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for '%s'; namelen=%d\n", pdns->queries[0]->name, pdns->queries[0]->namelen);
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)
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.";
782 unsigned long long ipv6prefix;
783 unsigned int comparelen;
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);
789 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_number(cfg, "vpn", "IPV6PREFIX", &ipv6prefix));
790 GNUNET_assert(ipv6prefix < 127);
791 ipv6prefix = (ipv6prefix + 7)/8;
793 for (i = ipv6prefix; i < 16; i++)
796 for (i = 0; i < 16; i++)
798 unsigned char c1 = ipv6[i] >> 4;
799 unsigned char c2 = ipv6[i] & 0xf;
802 ipv6rev[62-(4*i)] = c1 + '0';
804 ipv6rev[62-(4*i)] = c1 + 87; /* 87 is the difference between 'a' and 10 */
807 ipv6rev[62-((4*i)+2)] = c2 + '0';
809 ipv6rev[62-((4*i)+2)] = c2 + 87;
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),
817 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Reverse-Query for .gnunet!\n");
819 GNUNET_SCHEDULER_add_now(send_rev_query, pdns);
826 unsigned int virt_dns_bytes;
828 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
831 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
832 "No entry 'VIRTDNS' in configuration!\n");
836 if (1 != inet_pton (AF_INET, virt_dns, &virt_dns_bytes))
838 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
839 "Error parsing 'VIRTDNS': %s; %m!\n", virt_dns);
843 GNUNET_free(virt_dns);
845 if (virt_dns_bytes == pkt->orig_to)
847 /* This is a packet that was sent directly to the virtual dns-server
849 * This means we have to send this query over gnunet
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*);
856 cls_->hdr.type = ntohs(GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS);
857 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "size: %d\n", size);
859 memcpy(&cls_->dns, dns, cls_->hdr.size - sizeof(struct GNUNET_MessageHeader));
860 GNUNET_SCHEDULER_add_now(send_mesh_query, cls_);
866 /* The query should be sent to the network */
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;
873 GNUNET_NETWORK_socket_sendto(dnsout,
875 ntohs(pkt->hdr.size) - sizeof(struct query_packet) + 1,
876 (struct sockaddr*) &dest,
880 free_parsed_dns_packet(pdns);
883 GNUNET_SERVER_receive_done(client, GNUNET_OK);
886 static void read_response (void *cls,
887 const struct GNUNET_SCHEDULER_TaskContext *tc);
892 struct sockaddr_in addr;
894 dnsout = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
896 return GNUNET_SYSERR;
897 memset (&addr, 0, sizeof (struct sockaddr_in));
899 addr.sin_family = AF_INET;
900 int err = GNUNET_NETWORK_socket_bind (dnsout,
901 (struct sockaddr *) &addr,
902 sizeof (struct sockaddr_in));
904 if (err != GNUNET_OK)
906 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
907 "Could not bind a port: %m\n");
908 return GNUNET_SYSERR;
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);
916 dnsoutport = htons (addr.sin_port);
918 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Bound to port %d.\n", dnsoutport);
920 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, dnsout,
921 &read_response, NULL);
927 * Read a response-packet of the UDP-Socket
930 read_response (void *cls
931 __attribute__ ((unused)),
932 const struct GNUNET_SCHEDULER_TaskContext *tc)
934 struct sockaddr_in addr;
935 socklen_t addrlen = sizeof (addr);
939 if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
942 memset (&addr, 0, sizeof addr);
945 if (0 != ioctl (GNUNET_NETWORK_get_fd (dnsout), FIONREAD, &len))
947 unhijack (dnsoutport);
948 if (GNUNET_YES == open_port ())
949 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
953 /* port the code above? */
957 unsigned char buf[len];
958 struct dns_pkt *dns = (struct dns_pkt *) buf;
960 r = GNUNET_NETWORK_socket_recvfrom (dnsout,
963 (struct sockaddr *) &addr, &addrlen);
967 unhijack (dnsoutport);
968 if (GNUNET_YES == open_port ())
969 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
973 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer to query %d\n", ntohs(dns->s.id));
975 if (query_states[dns->s.id].valid == GNUNET_YES)
977 if (query_states[dns->s.id].tunnel != NULL)
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);
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);
987 GNUNET_MESH_tunnel_get_data (query_states[dns->s.id].tunnel))
989 struct GNUNET_MESH_TransmitHandle *th =
990 GNUNET_MESH_notify_transmit_ready (query_states[dns->s.id].tunnel,
993 GNUNET_TIME_UNIT_MINUTES,
997 GNUNET_MessageHeader),
998 mesh_send_response, c);
999 GNUNET_MESH_tunnel_set_data (query_states[dns->s.id].tunnel,
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);
1007 struct tunnel_notify_queue* element = GNUNET_malloc(sizeof(struct tunnel_notify_queue));
1009 element->len = r+sizeof(struct GNUNET_MessageHeader);
1010 element->cb = mesh_send_response;
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);
1019 query_states[dns->s.id].valid = GNUNET_NO;
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);
1033 GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
1035 GNUNET_SERVER_notify_transmit_ready (query_states
1036 [dns->s.id].client, len,
1037 GNUNET_TIME_UNIT_FOREVER_REL,
1039 query_states[dns->s.
1044 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
1045 dnsout, &read_response, NULL);
1050 * Task run during shutdown.
1056 cleanup_task (void *cls __attribute__((unused)),
1057 const struct GNUNET_SCHEDULER_TaskContext *tc)
1059 GNUNET_assert(0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
1061 unhijack(dnsoutport);
1062 GNUNET_DHT_disconnect(dht);
1066 * @brief Create a port-map from udp and tcp redirects
1068 * @param udp_redirects
1069 * @param tcp_redirects
1074 get_port_from_redirects (const char *udp_redirects, const char *tcp_redirects)
1077 char* cpy, *hostname, *redirect;
1078 int local_port, count = 0;
1080 if (NULL != udp_redirects)
1082 cpy = GNUNET_strdup (udp_redirects);
1083 for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
1085 if (NULL == (hostname = strstr (redirect, ":")))
1087 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
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);
1095 ret |= (0xFFFF & htons(local_port));
1109 if (NULL != tcp_redirects)
1111 cpy = GNUNET_strdup (tcp_redirects);
1112 for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
1114 if (NULL == (hostname = strstr (redirect, ":")))
1116 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
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);
1124 ret |= (0xFFFF & htons(local_port));
1145 publish_name (const char *name, uint64_t ports, uint32_t service_type,
1146 struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key)
1148 size_t size = sizeof (struct GNUNET_DNS_Record);
1149 struct GNUNET_DNS_Record data;
1150 memset (&data, 0, size);
1153 htonl (size - sizeof (struct GNUNET_CRYPTO_RsaSignature));
1154 data.purpose.purpose = GNUNET_SIGNATURE_PURPOSE_DNS_RECORD;
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));
1160 data.service_type = service_type;
1163 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &data.peer);
1165 data.expiration_time =
1166 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_HOURS, 2));
1168 /* Sign the block */
1169 if (GNUNET_OK != GNUNET_CRYPTO_rsa_sign (my_private_key,
1170 &data.purpose, &data.signature))
1172 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not sign DNS_Record\n");
1176 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1177 "Putting with key %08x, size = %d\n",
1178 *((unsigned int *) &data.service_descriptor), size);
1180 GNUNET_DHT_put (dht,
1181 &data.service_descriptor,
1182 DEFAULT_PUT_REPLICATION,
1184 GNUNET_BLOCK_TYPE_DNS,
1187 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_HOURS),
1188 GNUNET_TIME_UNIT_MINUTES, NULL, NULL);
1192 * @brief Publishes the record defined by the section section
1194 * @param cls closure
1195 * @param section the current section
1198 publish_iterate (void *cls __attribute__((unused)), const char *section)
1200 if ((strlen(section) < 8) || (0 != strcmp (".gnunet.", section + (strlen(section) - 8))))
1203 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Parsing dns-name %s\n", section);
1205 char *udp_redirects, *tcp_redirects, *alternative_names, *alternative_name,
1208 GNUNET_CONFIGURATION_get_value_string (cfg, section,
1209 "UDP_REDIRECTS", &udp_redirects);
1210 GNUNET_CONFIGURATION_get_value_string (cfg, section, "TCP_REDIRECTS",
1213 if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_filename (cfg, "GNUNETD",
1217 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not read keyfile-value\n");
1218 if (keyfile != NULL)
1219 GNUNET_free (keyfile);
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);
1228 uint64_t ports = get_port_from_redirects (udp_redirects, tcp_redirects);
1229 uint32_t service_type = 0;
1231 if (NULL != udp_redirects)
1232 service_type = GNUNET_DNS_SERVICE_TYPE_UDP;
1234 if (NULL != tcp_redirects)
1235 service_type |= GNUNET_DNS_SERVICE_TYPE_TCP;
1237 service_type = htonl (service_type);
1240 publish_name (section, ports, service_type, my_private_key);
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, " "))
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)] = '.';
1254 publish_name (altname, ports, service_type, my_private_key);
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);
1264 * Publish a DNS-record in the DHT.
1267 publish_names (void *cls __attribute__((unused)),
1268 const struct GNUNET_SCHEDULER_TaskContext *tc) {
1269 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1272 GNUNET_CONFIGURATION_iterate_sections(cfg, publish_iterate, NULL);
1274 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_HOURS,
1280 * @param cls closure
1281 * @param server the initialized server
1282 * @param cfg_ configuration to use
1286 struct GNUNET_SERVER_Handle *server,
1287 const struct GNUNET_CONFIGURATION_Handle *cfg_)
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)},
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},
1303 static GNUNET_MESH_ApplicationType *apptypes;
1305 if (GNUNET_YES != open_port ())
1307 GNUNET_SCHEDULER_shutdown();
1312 GNUNET_CONFIGURATION_get_value_yesno (cfg_, "dns", "PROVIDE_EXIT"))
1313 apptypes = (GNUNET_MESH_ApplicationType[])
1315 GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
1316 GNUNET_APPLICATION_TYPE_END};
1318 apptypes = (GNUNET_MESH_ApplicationType[])
1320 GNUNET_APPLICATION_TYPE_END};
1323 GNUNET_MESH_connect (cfg_, NULL, NULL, mesh_handlers, apptypes);
1328 for (i = 0; i < 65536; i++)
1330 query_states[i].valid = GNUNET_NO;
1333 dht = GNUNET_DHT_connect (cfg, 1024);
1335 GNUNET_SCHEDULER_add_now (publish_names, NULL);
1337 GNUNET_SERVER_add_handlers (server, handlers);
1338 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
1339 &cleanup_task, cls);
1343 * The main function for the dns service.
1345 * @param argc number of arguments from the command line
1346 * @param argv command line arguments
1347 * @return 0 ok, 1 on error
1350 main (int argc, char *const *argv)
1352 return (GNUNET_OK ==
1353 GNUNET_SERVICE_run (argc,
1356 GNUNET_SERVICE_OPTION_NONE,
1357 &run, NULL)) ? 0 : 1;