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);
305 GNUNET_free(element);
313 mesh_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
314 const struct GNUNET_TRANSPORT_ATS_Information *atsi
315 __attribute__ ((unused)))
319 struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
320 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
321 "Connected to peer %s, sending query with id %d\n",
322 GNUNET_i2s (peer), ntohs (cls_->dns.s.id));
324 if (NULL == GNUNET_MESH_tunnel_get_data (cls_->tunnel))
326 struct GNUNET_MESH_TransmitHandle *th =
327 GNUNET_MESH_notify_transmit_ready (cls_->tunnel,
330 GNUNET_TIME_UNIT_MINUTES,
336 GNUNET_MESH_tunnel_set_data (cls_->tunnel, th);
340 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(cls_->tunnel);
341 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(cls_->tunnel);
343 struct tunnel_notify_queue* element = GNUNET_malloc(sizeof(struct tunnel_notify_queue));
345 element->len = cls_->hdr.size;
346 element->cb = mesh_send;
348 GNUNET_CONTAINER_DLL_insert_tail(head, tail, element);
349 GNUNET_MESH_tunnel_set_head(cls_->tunnel, head);
350 GNUNET_MESH_tunnel_set_tail(cls_->tunnel, tail);
356 send_mesh_query (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
358 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
361 struct tunnel_cls *cls_ = (struct tunnel_cls*)cls;
363 if (NULL == dns_tunnel)
364 dns_tunnel = GNUNET_MESH_peer_request_connect_by_type(mesh_handle,
365 GNUNET_TIME_UNIT_HOURS,
366 GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
370 cls_->tunnel = dns_tunnel;
371 remote_pending[cls_->dns.s.id] = cls_;
375 receive_mesh_query (void *cls __attribute__((unused)),
376 struct GNUNET_MESH_Tunnel *tunnel,
377 void **ctx __attribute__((unused)),
378 const struct GNUNET_PeerIdentity *sender __attribute__((unused)),
379 const struct GNUNET_MessageHeader *message,
380 const struct GNUNET_TRANSPORT_ATS_Information *atsi __attribute__((unused)))
382 struct dns_pkt *dns = (struct dns_pkt*)(message + 1);
384 struct sockaddr_in dest;
385 memset(&dest, 0, sizeof dest);
386 dest.sin_port = htons(53);
387 /* TODO: read from config */
388 inet_pton(AF_INET, "8.8.8.8", &dest.sin_addr);
390 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Querying for remote, id=%d\n", ntohs(dns->s.id));
391 query_states[dns->s.id].tunnel = tunnel;
392 query_states[dns->s.id].valid = GNUNET_YES;
394 GNUNET_NETWORK_socket_sendto(dnsout,
396 ntohs(message->size) - sizeof(struct GNUNET_MessageHeader),
397 (struct sockaddr*) &dest,
400 return GNUNET_SYSERR;
404 receive_mesh_answer (void *cls __attribute__((unused)),
405 struct GNUNET_MESH_Tunnel *tunnel,
406 void **ctx __attribute__((unused)),
407 const struct GNUNET_PeerIdentity *sender,
408 const struct GNUNET_MessageHeader *message,
409 const struct GNUNET_TRANSPORT_ATS_Information *atsi __attribute__((unused)))
411 /* TODo: size check */
412 struct dns_pkt *dns = (struct dns_pkt *) (message + 1);
414 /* They sent us a packet we were not waiting for */
415 if (remote_pending[dns->s.id] == NULL
416 || remote_pending[dns->s.id]->tunnel != tunnel)
419 GNUNET_free(remote_pending[dns->s.id]);
420 remote_pending[dns->s.id] = NULL;
422 if (query_states[dns->s.id].valid != GNUNET_YES)
423 return GNUNET_SYSERR;
424 query_states[dns->s.id].valid = GNUNET_NO;
426 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Received answer from peer %s, dns-id %d\n", GNUNET_i2s(sender), ntohs(dns->s.id));
428 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 */
429 + sizeof (struct dns_record_line) - 1 + 16; /* To hold the IPv6-Address */
431 struct answer_packet_list *answer =
432 GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
433 memset (answer, 0, len + 2 * sizeof (struct answer_packet_list *));
435 answer->pkt.hdr.type = htons (GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
436 answer->pkt.hdr.size = htons (len);
438 struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
440 if (ntohs(pdns->s.ancount) < 1)
442 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer only contains %d answers.\n", ntohs(pdns->s.ancount));
443 free_parsed_dns_packet(pdns);
447 answer->pkt.addrsize = ntohs(pdns->answers[0]->data_len);
448 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "The first answer has the addrlen %d\n", answer->pkt.addrsize);
449 memcpy(answer->pkt.addr, pdns->answers[0]->data, ntohs(pdns->answers[0]->data_len));
451 answer->pkt.from = query_states[dns->s.id].remote_ip;
453 answer->pkt.to = query_states[dns->s.id].local_ip;
454 answer->pkt.dst_port = query_states[dns->s.id].local_port;
456 struct dns_pkt *dpkt = (struct dns_pkt *) answer->pkt.data;
458 dpkt->s.id = dns->s.id;
462 dpkt->s.qdcount = htons (1);
463 dpkt->s.ancount = htons (1);
465 memcpy (dpkt->data, query_states[dns->s.id].name,
466 query_states[dns->s.id].namelen);
467 GNUNET_free (query_states[dns->s.id].name);
469 struct dns_query_line *dque =
470 (struct dns_query_line *) (dpkt->data +
471 (query_states[dns->s.id].namelen));
473 struct dns_record_line *drec_data =
474 (struct dns_record_line *) (dpkt->data +
475 (query_states[dns->s.id].namelen) +
476 sizeof (struct dns_query_line) + 2);
477 if (16 == answer->pkt.addrsize)
479 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REMOTE_AAAA;
480 dque->type = htons (28); /* AAAA */
481 drec_data->type = htons (28); /* AAAA */
482 drec_data->data_len = htons (16);
486 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REMOTE_A;
487 dque->type = htons (1); /* A */
488 drec_data->type = htons (1); /* A*/
489 drec_data->data_len = htons (4);
491 dque->class = htons (1); /* IN */
494 (char *) (dpkt->data + (query_states[dns->s.id].namelen) +
495 sizeof (struct dns_query_line));
496 memcpy (anname, "\xc0\x0c", 2);
497 drec_data->class = htons (1); /* IN */
499 drec_data->ttl = pdns->answers[0]->ttl;
501 /* Calculate at which offset in the packet the IPv6-Address belongs, it is
502 * filled in by the daemon-vpn */
503 answer->pkt.addroffset =
504 htons ((unsigned short) ((unsigned long) (&drec_data->data) -
505 (unsigned long) (&answer->pkt)));
507 GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
509 GNUNET_SERVER_notify_transmit_ready (query_states[dns->s.id].client,
511 GNUNET_TIME_UNIT_FOREVER_REL,
513 query_states[dns->s.id].client);
515 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sent answer of length %d on to client, addroffset = %d\n", len, answer->pkt.addroffset);
517 free_parsed_dns_packet(pdns);
523 send_rev_query(void * cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
524 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
527 struct dns_pkt_parsed* pdns = (struct dns_pkt_parsed*) cls;
529 unsigned short id = pdns->s.id;
531 free_parsed_dns_packet(pdns);
533 if (query_states[id].valid != GNUNET_YES) return;
534 query_states[id].valid = GNUNET_NO;
536 GNUNET_assert(query_states[id].namelen == 74);
538 size_t len = sizeof(struct answer_packet) - 1 \
539 + sizeof(struct dns_static) \
540 + 74 /* this is the length of a reverse ipv6-lookup */ \
541 + sizeof(struct dns_query_line) \
542 + 2 /* To hold the pointer (as defined in RFC1035) to the name */ \
543 + sizeof(struct dns_record_line) - 1 \
544 - 2 /* We do not know the lenght of the answer yet*/;
546 struct answer_packet_list* answer = GNUNET_malloc(len + 2*sizeof(struct answer_packet_list*));
547 memset(answer, 0, len + 2*sizeof(struct answer_packet_list*));
549 answer->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
550 answer->pkt.hdr.size = htons(len);
551 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REV;
553 answer->pkt.from = query_states[id].remote_ip;
555 answer->pkt.to = query_states[id].local_ip;
556 answer->pkt.dst_port = query_states[id].local_port;
558 struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
564 dpkt->s.qdcount = htons(1);
565 dpkt->s.ancount = htons(1);
567 memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
568 GNUNET_free(query_states[id].name);
570 struct dns_query_line* dque = (struct dns_query_line*)(dpkt->data+(query_states[id].namelen));
571 dque->type = htons(12); /* PTR */
572 dque->class = htons(1); /* IN */
574 char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
575 memcpy(anname, "\xc0\x0c", 2);
577 struct dns_record_line *drec_data = (struct dns_record_line*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line)+2);
578 drec_data->type = htons(12); /* AAAA */
579 drec_data->class = htons(1); /* IN */
580 /* FIXME: read the TTL from block:
581 * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
583 * But how to get the seconds out of this?
585 drec_data->ttl = htonl(3600);
587 /* Calculate at which offset in the packet the length of the name and the
588 * name, it is filled in by the daemon-vpn */
589 answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data_len)-(unsigned long)(&answer->pkt)));
591 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
593 GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
595 GNUNET_TIME_UNIT_FOREVER_REL,
597 query_states[id].client);
601 * Receive a block from the dht.
604 receive_dht(void *cls,
605 struct GNUNET_TIME_Absolute exp __attribute__((unused)),
606 const GNUNET_HashCode *key __attribute__((unused)),
607 const struct GNUNET_PeerIdentity *const *get_path __attribute__((unused)),
608 const struct GNUNET_PeerIdentity *const *put_path __attribute__((unused)),
609 enum GNUNET_BLOCK_Type type,
613 unsigned short id = ((struct receive_dht_cls*)cls)->id;
614 struct GNUNET_DHT_GetHandle* handle = ((struct receive_dht_cls*)cls)->handle;
617 GNUNET_assert(type == GNUNET_BLOCK_TYPE_DNS);
619 /* If no query with this id is pending, ignore the block */
620 if (query_states[id].valid != GNUNET_YES) return;
621 query_states[id].valid = GNUNET_NO;
623 const struct GNUNET_DNS_Record* rec = data;
624 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
625 "Got block of size %d, peer: %08x, desc: %08x\n",
627 *((unsigned int*)&rec->peer),
628 *((unsigned int*)&rec->service_descriptor));
630 size_t len = sizeof(struct answer_packet) - 1 \
631 + sizeof(struct dns_static) \
632 + query_states[id].namelen \
633 + sizeof(struct dns_query_line) \
634 + 2 /* To hold the pointer (as defined in RFC1035) to the name */ \
635 + sizeof(struct dns_record_line) - 1 \
636 + 16; /* To hold the IPv6-Address */
638 struct answer_packet_list* answer = GNUNET_malloc(len + 2*sizeof(struct answer_packet_list*));
639 memset(answer, 0, len + 2*sizeof(struct answer_packet_list*));
641 answer->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
642 answer->pkt.hdr.size = htons(len);
643 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_SERVICE;
645 GNUNET_CRYPTO_hash(&rec->peer,
646 sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
647 &answer->pkt.service_descr.peer);
649 memcpy(&answer->pkt.service_descr.service_descriptor,
650 &rec->service_descriptor,
651 sizeof(GNUNET_HashCode));
652 memcpy(&answer->pkt.service_descr.service_type,
654 sizeof(answer->pkt.service_descr.service_type));
655 memcpy(&answer->pkt.service_descr.ports, &rec->ports, sizeof(answer->pkt.service_descr.ports));
657 answer->pkt.from = query_states[id].remote_ip;
659 answer->pkt.to = query_states[id].local_ip;
660 answer->pkt.dst_port = query_states[id].local_port;
662 struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
668 dpkt->s.qdcount = htons(1);
669 dpkt->s.ancount = htons(1);
671 memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
672 GNUNET_free(query_states[id].name);
674 struct dns_query_line* dque = (struct dns_query_line*)(dpkt->data+(query_states[id].namelen));
675 dque->type = htons(28); /* AAAA */
676 dque->class = htons(1); /* IN */
678 char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
679 memcpy(anname, "\xc0\x0c", 2);
681 struct dns_record_line *drec_data = (struct dns_record_line*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line)+2);
682 drec_data->type = htons(28); /* AAAA */
683 drec_data->class = htons(1); /* IN */
685 /* FIXME: read the TTL from block:
686 * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
688 * But how to get the seconds out of this?
690 drec_data->ttl = htonl(3600);
691 drec_data->data_len = htons(16);
693 /* Calculate at which offset in the packet the IPv6-Address belongs, it is
694 * filled in by the daemon-vpn */
695 answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data)-(unsigned long)(&answer->pkt)));
697 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
699 GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
701 GNUNET_TIME_UNIT_FOREVER_REL,
703 query_states[id].client);
705 GNUNET_DHT_get_stop(handle);
709 * This receives a GNUNET_MESSAGE_TYPE_REHIJACK and rehijacks the DNS
712 rehijack(void *cls __attribute__((unused)),
713 struct GNUNET_SERVER_Client *client,
714 const struct GNUNET_MessageHeader *message __attribute__((unused))) {
715 unhijack(dnsoutport);
716 GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
718 GNUNET_SERVER_receive_done(client, GNUNET_OK);
722 * This receives the dns-payload from the daemon-vpn and sends it on over the udp-socket
725 receive_query(void *cls __attribute__((unused)),
726 struct GNUNET_SERVER_Client *client,
727 const struct GNUNET_MessageHeader *message) {
728 struct query_packet* pkt = (struct query_packet*)message;
729 struct dns_pkt* dns = (struct dns_pkt*)pkt->data;
730 struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
732 query_states[dns->s.id].valid = GNUNET_YES;
733 query_states[dns->s.id].client = client;
734 query_states[dns->s.id].local_ip = pkt->orig_from;
735 query_states[dns->s.id].local_port = pkt->src_port;
736 query_states[dns->s.id].remote_ip = pkt->orig_to;
737 query_states[dns->s.id].namelen = strlen((char*)dns->data) + 1;
738 if (query_states[dns->s.id].name != NULL)
739 GNUNET_free(query_states[dns->s.id].name);
740 query_states[dns->s.id].name = GNUNET_malloc(query_states[dns->s.id].namelen);
741 memcpy(query_states[dns->s.id].name, dns->data, query_states[dns->s.id].namelen);
743 /* The query is for a .gnunet-address */
744 if (pdns->queries[0]->namelen > 9 &&
745 0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - 9), ".gnunet.", 9))
747 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for .gnunet!\n");
749 GNUNET_CRYPTO_hash(pdns->queries[0]->name, pdns->queries[0]->namelen, &key);
751 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
752 "Getting with key %08x, len is %d\n",
753 *((unsigned int*)&key),
754 pdns->queries[0]->namelen);
756 struct receive_dht_cls* cls = GNUNET_malloc(sizeof(struct receive_dht_cls));
759 cls->handle = GNUNET_DHT_get_start(dht,
760 GNUNET_TIME_UNIT_MINUTES,
761 GNUNET_BLOCK_TYPE_DNS,
763 DEFAULT_GET_REPLICATION,
775 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for '%s'; namelen=%d\n", pdns->queries[0]->name, pdns->queries[0]->namelen);
777 /* This is a PTR-Query. Check if it is for "our" network */
778 if (htons(pdns->queries[0]->qtype) == 12 &&
779 74 == pdns->queries[0]->namelen)
783 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.";
785 unsigned long long ipv6prefix;
786 unsigned int comparelen;
788 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_string(cfg, "vpn", "IPV6ADDR", &ipv6addr));
789 inet_pton (AF_INET6, ipv6addr, ipv6);
790 GNUNET_free(ipv6addr);
792 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_number(cfg, "vpn", "IPV6PREFIX", &ipv6prefix));
793 GNUNET_assert(ipv6prefix < 127);
794 ipv6prefix = (ipv6prefix + 7)/8;
796 for (i = ipv6prefix; i < 16; i++)
799 for (i = 0; i < 16; i++)
801 unsigned char c1 = ipv6[i] >> 4;
802 unsigned char c2 = ipv6[i] & 0xf;
805 ipv6rev[62-(4*i)] = c1 + '0';
807 ipv6rev[62-(4*i)] = c1 + 87; /* 87 is the difference between 'a' and 10 */
810 ipv6rev[62-((4*i)+2)] = c2 + '0';
812 ipv6rev[62-((4*i)+2)] = c2 + 87;
814 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "My network is %s'.\n", ipv6rev);
815 comparelen = 10 + 4*ipv6prefix;
816 if(0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - comparelen),
817 ipv6rev + (74 - comparelen),
820 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Reverse-Query for .gnunet!\n");
822 GNUNET_SCHEDULER_add_now(send_rev_query, pdns);
829 unsigned int virt_dns_bytes;
831 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
834 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
835 "No entry 'VIRTDNS' in configuration!\n");
839 if (1 != inet_pton (AF_INET, virt_dns, &virt_dns_bytes))
841 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
842 "Error parsing 'VIRTDNS': %s; %m!\n", virt_dns);
846 GNUNET_free(virt_dns);
848 if (virt_dns_bytes == pkt->orig_to)
850 /* This is a packet that was sent directly to the virtual dns-server
852 * This means we have to send this query over gnunet
855 size_t size = sizeof(struct GNUNET_MESH_Tunnel*) + sizeof(struct GNUNET_MessageHeader) + (ntohs(message->size) - sizeof(struct query_packet) + 1);
856 struct tunnel_cls *cls_ = GNUNET_malloc(size);
857 cls_->hdr.size = size - sizeof(struct GNUNET_MESH_Tunnel*);
859 cls_->hdr.type = ntohs(GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS);
860 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "size: %d\n", size);
862 memcpy(&cls_->dns, dns, cls_->hdr.size - sizeof(struct GNUNET_MessageHeader));
863 GNUNET_SCHEDULER_add_now(send_mesh_query, cls_);
869 /* The query should be sent to the network */
871 struct sockaddr_in dest;
872 memset(&dest, 0, sizeof dest);
873 dest.sin_port = htons(53);
874 dest.sin_addr.s_addr = pkt->orig_to;
876 GNUNET_NETWORK_socket_sendto(dnsout,
878 ntohs(pkt->hdr.size) - sizeof(struct query_packet) + 1,
879 (struct sockaddr*) &dest,
883 free_parsed_dns_packet(pdns);
886 GNUNET_SERVER_receive_done(client, GNUNET_OK);
889 static void read_response (void *cls,
890 const struct GNUNET_SCHEDULER_TaskContext *tc);
895 struct sockaddr_in addr;
897 dnsout = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
899 return GNUNET_SYSERR;
900 memset (&addr, 0, sizeof (struct sockaddr_in));
902 addr.sin_family = AF_INET;
903 int err = GNUNET_NETWORK_socket_bind (dnsout,
904 (struct sockaddr *) &addr,
905 sizeof (struct sockaddr_in));
907 if (err != GNUNET_OK)
909 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
910 "Could not bind a port: %m\n");
911 return GNUNET_SYSERR;
914 /* Read the port we bound to */
915 socklen_t addrlen = sizeof (struct sockaddr_in);
916 err = getsockname (GNUNET_NETWORK_get_fd (dnsout),
917 (struct sockaddr *) &addr, &addrlen);
919 dnsoutport = htons (addr.sin_port);
921 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Bound to port %d.\n", dnsoutport);
923 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, dnsout,
924 &read_response, NULL);
930 * Read a response-packet of the UDP-Socket
933 read_response (void *cls
934 __attribute__ ((unused)),
935 const struct GNUNET_SCHEDULER_TaskContext *tc)
937 struct sockaddr_in addr;
938 socklen_t addrlen = sizeof (addr);
942 if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
945 memset (&addr, 0, sizeof addr);
948 if (0 != ioctl (GNUNET_NETWORK_get_fd (dnsout), FIONREAD, &len))
950 unhijack (dnsoutport);
951 if (GNUNET_YES == open_port ())
952 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
956 /* port the code above? */
960 unsigned char buf[len];
961 struct dns_pkt *dns = (struct dns_pkt *) buf;
963 r = GNUNET_NETWORK_socket_recvfrom (dnsout,
966 (struct sockaddr *) &addr, &addrlen);
970 unhijack (dnsoutport);
971 if (GNUNET_YES == open_port ())
972 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
976 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer to query %d\n", ntohs(dns->s.id));
978 if (query_states[dns->s.id].valid == GNUNET_YES)
980 if (query_states[dns->s.id].tunnel != NULL)
982 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer to query %d for a remote peer!\n", ntohs(dns->s.id));
983 /* This response should go through a tunnel */
984 uint32_t *c = GNUNET_malloc (4 + sizeof(struct GNUNET_MESH_Tunnel*) + r);
986 struct GNUNET_MESH_Tunnel** t = (struct GNUNET_MESH_Tunnel**)(c + 1);
987 *t = query_states[dns->s.id].tunnel;
988 memcpy (t + 1, dns, r);
990 GNUNET_MESH_tunnel_get_data (query_states[dns->s.id].tunnel))
992 struct GNUNET_MESH_TransmitHandle *th =
993 GNUNET_MESH_notify_transmit_ready (query_states[dns->s.id].tunnel,
996 GNUNET_TIME_UNIT_MINUTES,
1000 GNUNET_MessageHeader),
1001 mesh_send_response, c);
1002 GNUNET_MESH_tunnel_set_data (query_states[dns->s.id].tunnel,
1007 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(query_states[dns->s.id].tunnel);
1008 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(query_states[dns->s.id].tunnel);
1010 struct tunnel_notify_queue* element = GNUNET_malloc(sizeof(struct tunnel_notify_queue));
1012 element->len = r+sizeof(struct GNUNET_MessageHeader);
1013 element->cb = mesh_send_response;
1015 GNUNET_CONTAINER_DLL_insert_tail(head, tail, element);
1016 GNUNET_MESH_tunnel_set_head(query_states[dns->s.id].tunnel, head);
1017 GNUNET_MESH_tunnel_set_tail(query_states[dns->s.id].tunnel, tail);
1022 query_states[dns->s.id].valid = GNUNET_NO;
1024 size_t len = sizeof (struct answer_packet) + r - 1; /* 1 for the unsigned char data[1]; */
1025 struct answer_packet_list *answer =
1026 GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
1027 answer->pkt.hdr.type =
1028 htons (GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
1029 answer->pkt.hdr.size = htons (len);
1030 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_IP;
1031 answer->pkt.from = addr.sin_addr.s_addr;
1032 answer->pkt.to = query_states[dns->s.id].local_ip;
1033 answer->pkt.dst_port = query_states[dns->s.id].local_port;
1034 memcpy (answer->pkt.data, buf, r);
1036 GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
1038 GNUNET_SERVER_notify_transmit_ready (query_states
1039 [dns->s.id].client, len,
1040 GNUNET_TIME_UNIT_FOREVER_REL,
1042 query_states[dns->s.
1047 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
1048 dnsout, &read_response, NULL);
1053 * Task run during shutdown.
1059 cleanup_task (void *cls __attribute__((unused)),
1060 const struct GNUNET_SCHEDULER_TaskContext *tc)
1062 GNUNET_assert(0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
1064 unhijack(dnsoutport);
1065 GNUNET_DHT_disconnect(dht);
1066 GNUNET_MESH_disconnect(mesh_handle);
1070 * @brief Create a port-map from udp and tcp redirects
1072 * @param udp_redirects
1073 * @param tcp_redirects
1078 get_port_from_redirects (const char *udp_redirects, const char *tcp_redirects)
1081 char* cpy, *hostname, *redirect;
1082 int local_port, count = 0;
1084 if (NULL != udp_redirects)
1086 cpy = GNUNET_strdup (udp_redirects);
1087 for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
1089 if (NULL == (hostname = strstr (redirect, ":")))
1091 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
1095 local_port = atoi (redirect);
1096 if (!((local_port > 0) && (local_port < 65536)))
1097 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: %s is not a correct port.", redirect);
1099 ret |= (0xFFFF & htons(local_port));
1113 if (NULL != tcp_redirects)
1115 cpy = GNUNET_strdup (tcp_redirects);
1116 for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
1118 if (NULL == (hostname = strstr (redirect, ":")))
1120 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
1124 local_port = atoi (redirect);
1125 if (!((local_port > 0) && (local_port < 65536)))
1126 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: %s is not a correct port.", redirect);
1128 ret |= (0xFFFF & htons(local_port));
1149 publish_name (const char *name, uint64_t ports, uint32_t service_type,
1150 struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key)
1152 size_t size = sizeof (struct GNUNET_DNS_Record);
1153 struct GNUNET_DNS_Record data;
1154 memset (&data, 0, size);
1157 htonl (size - sizeof (struct GNUNET_CRYPTO_RsaSignature));
1158 data.purpose.purpose = GNUNET_SIGNATURE_PURPOSE_DNS_RECORD;
1160 GNUNET_CRYPTO_hash (name, strlen (name) + 1, &data.service_descriptor);
1161 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Store with key1 %x\n",
1162 *((unsigned long long *) &data.service_descriptor));
1164 data.service_type = service_type;
1167 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &data.peer);
1169 data.expiration_time =
1170 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_HOURS, 2));
1172 /* Sign the block */
1173 if (GNUNET_OK != GNUNET_CRYPTO_rsa_sign (my_private_key,
1174 &data.purpose, &data.signature))
1176 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not sign DNS_Record\n");
1180 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1181 "Putting with key %08x, size = %d\n",
1182 *((unsigned int *) &data.service_descriptor), size);
1184 GNUNET_DHT_put (dht,
1185 &data.service_descriptor,
1186 DEFAULT_PUT_REPLICATION,
1188 GNUNET_BLOCK_TYPE_DNS,
1191 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_HOURS),
1192 GNUNET_TIME_UNIT_MINUTES, NULL, NULL);
1196 * @brief Publishes the record defined by the section section
1198 * @param cls closure
1199 * @param section the current section
1202 publish_iterate (void *cls __attribute__((unused)), const char *section)
1204 if ((strlen(section) < 8) || (0 != strcmp (".gnunet.", section + (strlen(section) - 8))))
1207 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Parsing dns-name %s\n", section);
1209 char *udp_redirects, *tcp_redirects, *alternative_names, *alternative_name,
1212 GNUNET_CONFIGURATION_get_value_string (cfg, section,
1213 "UDP_REDIRECTS", &udp_redirects);
1214 GNUNET_CONFIGURATION_get_value_string (cfg, section, "TCP_REDIRECTS",
1217 if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_filename (cfg, "GNUNETD",
1221 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not read keyfile-value\n");
1222 if (keyfile != NULL)
1223 GNUNET_free (keyfile);
1227 struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key =
1228 GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
1229 GNUNET_free (keyfile);
1230 GNUNET_assert (my_private_key != NULL);
1232 uint64_t ports = get_port_from_redirects (udp_redirects, tcp_redirects);
1233 uint32_t service_type = 0;
1235 if (NULL != udp_redirects)
1236 service_type = GNUNET_DNS_SERVICE_TYPE_UDP;
1238 if (NULL != tcp_redirects)
1239 service_type |= GNUNET_DNS_SERVICE_TYPE_TCP;
1241 service_type = htonl (service_type);
1244 publish_name (section, ports, service_type, my_private_key);
1246 GNUNET_CONFIGURATION_get_value_string (cfg, section,
1247 "ALTERNATIVE_NAMES",
1248 &alternative_names);
1249 for (alternative_name = strtok (alternative_names, " ");
1250 alternative_name != NULL; alternative_name = strtok (NULL, " "))
1253 alloca (strlen (alternative_name) + strlen (section) + 1 + 1);
1254 strcpy (altname, alternative_name);
1255 strcpy (altname + strlen (alternative_name) + 1, section);
1256 altname[strlen (alternative_name)] = '.';
1258 publish_name (altname, ports, service_type, my_private_key);
1261 GNUNET_free_non_null(alternative_names);
1262 GNUNET_CRYPTO_rsa_key_free (my_private_key);
1263 GNUNET_free_non_null (udp_redirects);
1264 GNUNET_free_non_null (tcp_redirects);
1268 * Publish a DNS-record in the DHT.
1271 publish_names (void *cls __attribute__((unused)),
1272 const struct GNUNET_SCHEDULER_TaskContext *tc) {
1273 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1276 GNUNET_CONFIGURATION_iterate_sections(cfg, publish_iterate, NULL);
1278 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_HOURS,
1284 * @param cls closure
1285 * @param server the initialized server
1286 * @param cfg_ configuration to use
1290 struct GNUNET_SERVER_Handle *server,
1291 const struct GNUNET_CONFIGURATION_Handle *cfg_)
1293 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
1294 /* callback, cls, type, size */
1295 {&receive_query, NULL, GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS, 0},
1296 {&rehijack, NULL, GNUNET_MESSAGE_TYPE_REHIJACK,
1297 sizeof (struct GNUNET_MessageHeader)},
1301 static const struct GNUNET_MESH_MessageHandler mesh_handlers[] = {
1302 {receive_mesh_query, GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS, 0},
1303 {receive_mesh_answer, GNUNET_MESSAGE_TYPE_REMOTE_ANSWER_DNS, 0},
1307 static GNUNET_MESH_ApplicationType *apptypes;
1309 if (GNUNET_YES != open_port ())
1311 GNUNET_SCHEDULER_shutdown();
1316 GNUNET_CONFIGURATION_get_value_yesno (cfg_, "dns", "PROVIDE_EXIT"))
1317 apptypes = (GNUNET_MESH_ApplicationType[])
1319 GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
1320 GNUNET_APPLICATION_TYPE_END};
1322 apptypes = (GNUNET_MESH_ApplicationType[])
1324 GNUNET_APPLICATION_TYPE_END};
1327 GNUNET_MESH_connect (cfg_, NULL, NULL, mesh_handlers, apptypes);
1332 for (i = 0; i < 65536; i++)
1334 query_states[i].valid = GNUNET_NO;
1337 dht = GNUNET_DHT_connect (cfg, 1024);
1339 GNUNET_SCHEDULER_add_now (publish_names, NULL);
1341 GNUNET_SERVER_add_handlers (server, handlers);
1342 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
1343 &cleanup_task, cls);
1347 * The main function for the dns service.
1349 * @param argc number of arguments from the command line
1350 * @param argv command line arguments
1351 * @return 0 ok, 1 on error
1354 main (int argc, char *const *argv)
1356 return (GNUNET_OK ==
1357 GNUNET_SERVICE_run (argc,
1360 GNUNET_SERVICE_OPTION_NONE,
1361 &run, NULL)) ? 0 : 1;