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 struct GNUNET_OS_Process *proc;
134 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
137 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
138 "No entry 'VIRTDNS' in configuration!\n");
142 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Hijacking, port is %d\n", dnsoutport);
143 snprintf (port_s, 6, "%d", dnsoutport);
144 if (NULL != (proc = GNUNET_OS_start_process (NULL,
146 "gnunet-helper-hijack-dns",
148 port_s, virt_dns, NULL)))
149 GNUNET_OS_process_close (proc);
150 GNUNET_free (virt_dns);
154 * Delete the hijacking-routes
157 unhijack (unsigned short port)
161 struct GNUNET_OS_Process *proc;
164 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
167 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
168 "No entry 'VIRTDNS' in configuration!\n");
172 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "unHijacking, port is %d\n", port);
173 snprintf (port_s, 6, "%d", port);
174 if (NULL != (proc = GNUNET_OS_start_process (NULL,
176 "gnunet-helper-hijack-dns",
178 "-d", port_s, virt_dns, NULL)))
179 GNUNET_OS_process_close (proc);
180 GNUNET_free (virt_dns);
184 * Send the DNS-Response to the client. Gets called via the notify_transmit_ready-
188 send_answer(void* cls, size_t size, void* buf) {
189 struct answer_packet_list* query = head;
190 size_t len = ntohs(query->pkt.hdr.size);
192 GNUNET_assert(len <= size);
194 memcpy(buf, &query->pkt.hdr, len);
196 GNUNET_CONTAINER_DLL_remove (head, tail, query);
200 /* When more data is to be sent, reschedule */
202 GNUNET_SERVER_notify_transmit_ready(cls,
203 ntohs(head->pkt.hdr.size),
204 GNUNET_TIME_UNIT_FOREVER_REL,
212 struct GNUNET_MESH_Tunnel *tunnel GNUNET_PACKED;
213 struct GNUNET_MessageHeader hdr;
217 struct tunnel_cls *remote_pending[UINT16_MAX];
220 mesh_send_response (void *cls, size_t size, void *buf)
222 GNUNET_assert (size >= sizeof (struct GNUNET_MessageHeader));
223 struct GNUNET_MessageHeader *hdr = buf;
225 struct GNUNET_MESH_Tunnel **tunnel = (struct GNUNET_MESH_Tunnel**)(sz+1);
226 struct dns_pkt *dns = (struct dns_pkt *) (tunnel + 1);
227 hdr->type = htons (GNUNET_MESSAGE_TYPE_REMOTE_ANSWER_DNS);
228 hdr->size = htons (*sz + sizeof (struct GNUNET_MessageHeader));
230 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
231 "Sending response, size=%d, sz=%d, sz+hdr=%d\n", size, *sz,
232 *sz + sizeof (struct GNUNET_MessageHeader));
234 GNUNET_assert (size >= (*sz + sizeof (struct GNUNET_MessageHeader)));
236 memcpy (hdr + 1, dns, *sz);
239 if (NULL != GNUNET_MESH_tunnel_get_head(*tunnel))
241 struct tunnel_notify_queue* element = GNUNET_MESH_tunnel_get_head(*tunnel);
242 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(*tunnel);
243 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(*tunnel);
245 GNUNET_CONTAINER_DLL_remove(head, tail, element);
247 GNUNET_MESH_tunnel_set_head(*tunnel, head);
248 GNUNET_MESH_tunnel_set_tail(*tunnel, tail);
249 struct GNUNET_MESH_TransmitHandle* th = GNUNET_MESH_notify_transmit_ready (*tunnel,
252 GNUNET_TIME_relative_divide
253 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
254 (const struct GNUNET_PeerIdentity *)
256 element->cb, element->cls);
257 /* save the handle */
258 GNUNET_MESH_tunnel_set_data(*tunnel, th);
260 return ntohs (hdr->size);
264 mesh_send (void *cls, size_t size, void *buf)
266 struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
267 GNUNET_MESH_tunnel_set_data(cls_->tunnel, NULL);
269 GNUNET_assert(cls_->hdr.size <= size);
271 size = cls_->hdr.size;
272 cls_->hdr.size = htons(cls_->hdr.size);
274 memcpy(buf, &cls_->hdr, size);
276 if (NULL != GNUNET_MESH_tunnel_get_head(cls_->tunnel))
278 struct tunnel_notify_queue* element = GNUNET_MESH_tunnel_get_head(cls_->tunnel);
279 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(cls_->tunnel);
280 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(cls_->tunnel);
282 GNUNET_CONTAINER_DLL_remove(head, tail, element);
284 GNUNET_MESH_tunnel_set_head(cls_->tunnel, head);
285 GNUNET_MESH_tunnel_set_tail(cls_->tunnel, tail);
286 struct GNUNET_MESH_TransmitHandle* th = GNUNET_MESH_notify_transmit_ready (cls_->tunnel,
289 GNUNET_TIME_relative_divide
290 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
291 (const struct GNUNET_PeerIdentity *)
293 element->cb, element->cls);
294 /* save the handle */
295 GNUNET_MESH_tunnel_set_data(cls_->tunnel, th);
304 mesh_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
305 const struct GNUNET_TRANSPORT_ATS_Information *atsi
306 __attribute__ ((unused)))
310 struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
311 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
312 "Connected to peer %s, sending query with id %d\n",
313 GNUNET_i2s (peer), ntohs (cls_->dns.s.id));
315 if (NULL == GNUNET_MESH_tunnel_get_data (cls_->tunnel))
317 struct GNUNET_MESH_TransmitHandle *th =
318 GNUNET_MESH_notify_transmit_ready (cls_->tunnel,
321 GNUNET_TIME_UNIT_MINUTES,
327 GNUNET_MESH_tunnel_set_data (cls_->tunnel, th);
331 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(cls_->tunnel);
332 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(cls_->tunnel);
334 struct tunnel_notify_queue* element = GNUNET_malloc(sizeof(struct tunnel_notify_queue));
336 element->len = cls_->hdr.size;
337 element->cb = mesh_send;
339 GNUNET_CONTAINER_DLL_insert_tail(head, tail, element);
340 GNUNET_MESH_tunnel_set_head(cls_->tunnel, head);
341 GNUNET_MESH_tunnel_set_tail(cls_->tunnel, tail);
347 send_mesh_query (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
349 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
352 struct tunnel_cls *cls_ = (struct tunnel_cls*)cls;
354 if (NULL == dns_tunnel)
355 dns_tunnel = GNUNET_MESH_peer_request_connect_by_type(mesh_handle,
356 GNUNET_TIME_UNIT_HOURS,
357 GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
361 cls_->tunnel = dns_tunnel;
362 remote_pending[cls_->dns.s.id] = cls_;
366 receive_mesh_query (void *cls __attribute__((unused)),
367 struct GNUNET_MESH_Tunnel *tunnel,
368 void **ctx __attribute__((unused)),
369 const struct GNUNET_PeerIdentity *sender __attribute__((unused)),
370 const struct GNUNET_MessageHeader *message,
371 const struct GNUNET_TRANSPORT_ATS_Information *atsi __attribute__((unused)))
373 struct dns_pkt *dns = (struct dns_pkt*)(message + 1);
375 struct sockaddr_in dest;
376 memset(&dest, 0, sizeof dest);
377 dest.sin_port = htons(53);
378 /* TODO: read from config */
379 inet_pton(AF_INET, "8.8.8.8", &dest.sin_addr);
381 query_states[dns->s.id].tunnel = tunnel;
382 query_states[dns->s.id].valid = GNUNET_YES;
384 GNUNET_NETWORK_socket_sendto(dnsout,
386 ntohs(message->size) - sizeof(struct GNUNET_MessageHeader),
387 (struct sockaddr*) &dest,
390 return GNUNET_SYSERR;
394 receive_mesh_answer (void *cls __attribute__((unused)),
395 struct GNUNET_MESH_Tunnel *tunnel,
396 void **ctx __attribute__((unused)),
397 const struct GNUNET_PeerIdentity *sender,
398 const struct GNUNET_MessageHeader *message,
399 const struct GNUNET_TRANSPORT_ATS_Information *atsi __attribute__((unused)))
401 /* TODo: size check */
402 struct dns_pkt *dns = (struct dns_pkt *) (message + 1);
404 /* They sent us a packet we were not waiting for */
405 if (remote_pending[dns->s.id] == NULL
406 || remote_pending[dns->s.id]->tunnel != tunnel)
407 return GNUNET_SYSERR;
408 if (query_states[dns->s.id].valid != GNUNET_YES)
409 return GNUNET_SYSERR;
410 query_states[dns->s.id].valid = GNUNET_NO;
412 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Received answer from peer %s, dns-id %d\n", GNUNET_i2s(sender), ntohs(dns->s.id));
414 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 */
415 + sizeof (struct dns_record_line) - 1 + 16; /* To hold the IPv6-Address */
417 struct answer_packet_list *answer =
418 GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
419 memset (answer, 0, len + 2 * sizeof (struct answer_packet_list *));
421 answer->pkt.hdr.type = htons (GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
422 answer->pkt.hdr.size = htons (len);
423 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REMOTE;
425 struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
427 if (ntohs(pdns->s.ancount) < 1)
429 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer only contains %d answers.\n", ntohs(pdns->s.ancount));
430 free_parsed_dns_packet(pdns);
434 answer->pkt.addrsize = ntohs(pdns->answers[0]->data_len);
435 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "The first answer has the addrlen %d\n", answer->pkt.addrsize);
436 memcpy(answer->pkt.addr, pdns->answers[0]->data, ntohs(pdns->answers[0]->data_len));
438 answer->pkt.from = query_states[dns->s.id].remote_ip;
440 answer->pkt.to = query_states[dns->s.id].local_ip;
441 answer->pkt.dst_port = query_states[dns->s.id].local_port;
443 struct dns_pkt *dpkt = (struct dns_pkt *) answer->pkt.data;
445 dpkt->s.id = dns->s.id;
449 dpkt->s.qdcount = htons (1);
450 dpkt->s.ancount = htons (1);
452 memcpy (dpkt->data, query_states[dns->s.id].name,
453 query_states[dns->s.id].namelen);
454 GNUNET_free (query_states[dns->s.id].name);
456 struct dns_query_line *dque =
457 (struct dns_query_line *) (dpkt->data +
458 (query_states[dns->s.id].namelen));
459 dque->type = htons (28); /* AAAA */
460 dque->class = htons (1); /* IN */
463 (char *) (dpkt->data + (query_states[dns->s.id].namelen) +
464 sizeof (struct dns_query_line));
465 memcpy (anname, "\xc0\x0c", 2);
467 struct dns_record_line *drec_data =
468 (struct dns_record_line *) (dpkt->data +
469 (query_states[dns->s.id].namelen) +
470 sizeof (struct dns_query_line) + 2);
471 drec_data->type = htons (28); /* AAAA */
472 drec_data->class = htons (1); /* IN */
474 drec_data->ttl = pdns->answers[0]->ttl;
475 drec_data->data_len = htons (16);
477 /* Calculate at which offset in the packet the IPv6-Address belongs, it is
478 * filled in by the daemon-vpn */
479 answer->pkt.addroffset =
480 htons ((unsigned short) ((unsigned long) (&drec_data->data) -
481 (unsigned long) (&answer->pkt)));
483 GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
485 GNUNET_SERVER_notify_transmit_ready (query_states[dns->s.id].client,
487 GNUNET_TIME_UNIT_FOREVER_REL,
489 query_states[dns->s.id].client);
491 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sent answer of length %d on to client, addroffset = %d\n", len, answer->pkt.addroffset);
493 free_parsed_dns_packet(pdns);
499 send_rev_query(void * cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
500 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
503 struct dns_pkt_parsed* pdns = (struct dns_pkt_parsed*) cls;
505 unsigned short id = pdns->s.id;
507 free_parsed_dns_packet(pdns);
509 if (query_states[id].valid != GNUNET_YES) return;
510 query_states[id].valid = GNUNET_NO;
512 GNUNET_assert(query_states[id].namelen == 74);
514 size_t len = sizeof(struct answer_packet) - 1 \
515 + sizeof(struct dns_static) \
516 + 74 /* this is the length of a reverse ipv6-lookup */ \
517 + sizeof(struct dns_query_line) \
518 + 2 /* To hold the pointer (as defined in RFC1035) to the name */ \
519 + sizeof(struct dns_record_line) - 1 \
520 - 2 /* We do not know the lenght of the answer yet*/;
522 struct answer_packet_list* answer = GNUNET_malloc(len + 2*sizeof(struct answer_packet_list*));
523 memset(answer, 0, len + 2*sizeof(struct answer_packet_list*));
525 answer->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
526 answer->pkt.hdr.size = htons(len);
527 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REV;
529 answer->pkt.from = query_states[id].remote_ip;
531 answer->pkt.to = query_states[id].local_ip;
532 answer->pkt.dst_port = query_states[id].local_port;
534 struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
540 dpkt->s.qdcount = htons(1);
541 dpkt->s.ancount = htons(1);
543 memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
544 GNUNET_free(query_states[id].name);
546 struct dns_query_line* dque = (struct dns_query_line*)(dpkt->data+(query_states[id].namelen));
547 dque->type = htons(12); /* PTR */
548 dque->class = htons(1); /* IN */
550 char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
551 memcpy(anname, "\xc0\x0c", 2);
553 struct dns_record_line *drec_data = (struct dns_record_line*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line)+2);
554 drec_data->type = htons(12); /* AAAA */
555 drec_data->class = htons(1); /* IN */
556 /* FIXME: read the TTL from block:
557 * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
559 * But how to get the seconds out of this?
561 drec_data->ttl = htonl(3600);
563 /* Calculate at which offset in the packet the length of the name and the
564 * name, it is filled in by the daemon-vpn */
565 answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data_len)-(unsigned long)(&answer->pkt)));
567 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
569 GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
571 GNUNET_TIME_UNIT_FOREVER_REL,
573 query_states[id].client);
577 * Receive a block from the dht.
580 receive_dht(void *cls,
581 struct GNUNET_TIME_Absolute exp __attribute__((unused)),
582 const GNUNET_HashCode *key __attribute__((unused)),
583 const struct GNUNET_PeerIdentity *const *get_path __attribute__((unused)),
584 const struct GNUNET_PeerIdentity *const *put_path __attribute__((unused)),
585 enum GNUNET_BLOCK_Type type,
589 unsigned short id = ((struct receive_dht_cls*)cls)->id;
590 struct GNUNET_DHT_GetHandle* handle = ((struct receive_dht_cls*)cls)->handle;
593 GNUNET_assert(type == GNUNET_BLOCK_TYPE_DNS);
595 /* If no query with this id is pending, ignore the block */
596 if (query_states[id].valid != GNUNET_YES) return;
597 query_states[id].valid = GNUNET_NO;
599 const struct GNUNET_DNS_Record* rec = data;
600 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
601 "Got block of size %d, peer: %08x, desc: %08x\n",
603 *((unsigned int*)&rec->peer),
604 *((unsigned int*)&rec->service_descriptor));
606 size_t len = sizeof(struct answer_packet) - 1 \
607 + sizeof(struct dns_static) \
608 + query_states[id].namelen \
609 + sizeof(struct dns_query_line) \
610 + 2 /* To hold the pointer (as defined in RFC1035) to the name */ \
611 + sizeof(struct dns_record_line) - 1 \
612 + 16; /* To hold the IPv6-Address */
614 struct answer_packet_list* answer = GNUNET_malloc(len + 2*sizeof(struct answer_packet_list*));
615 memset(answer, 0, len + 2*sizeof(struct answer_packet_list*));
617 answer->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
618 answer->pkt.hdr.size = htons(len);
619 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_SERVICE;
621 GNUNET_CRYPTO_hash(&rec->peer,
622 sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
623 &answer->pkt.service_descr.peer);
625 memcpy(&answer->pkt.service_descr.service_descriptor,
626 &rec->service_descriptor,
627 sizeof(GNUNET_HashCode));
628 memcpy(&answer->pkt.service_descr.service_type,
630 sizeof(answer->pkt.service_descr.service_type));
631 memcpy(&answer->pkt.service_descr.ports, &rec->ports, sizeof(answer->pkt.service_descr.ports));
633 answer->pkt.from = query_states[id].remote_ip;
635 answer->pkt.to = query_states[id].local_ip;
636 answer->pkt.dst_port = query_states[id].local_port;
638 struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
644 dpkt->s.qdcount = htons(1);
645 dpkt->s.ancount = htons(1);
647 memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
648 GNUNET_free(query_states[id].name);
650 struct dns_query_line* dque = (struct dns_query_line*)(dpkt->data+(query_states[id].namelen));
651 dque->type = htons(28); /* AAAA */
652 dque->class = htons(1); /* IN */
654 char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
655 memcpy(anname, "\xc0\x0c", 2);
657 struct dns_record_line *drec_data = (struct dns_record_line*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line)+2);
658 drec_data->type = htons(28); /* AAAA */
659 drec_data->class = htons(1); /* IN */
661 /* FIXME: read the TTL from block:
662 * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
664 * But how to get the seconds out of this?
666 drec_data->ttl = htonl(3600);
667 drec_data->data_len = htons(16);
669 /* Calculate at which offset in the packet the IPv6-Address belongs, it is
670 * filled in by the daemon-vpn */
671 answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data)-(unsigned long)(&answer->pkt)));
673 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
675 GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
677 GNUNET_TIME_UNIT_FOREVER_REL,
679 query_states[id].client);
681 GNUNET_DHT_get_stop(handle);
685 * This receives a GNUNET_MESSAGE_TYPE_REHIJACK and rehijacks the DNS
688 rehijack(void *cls __attribute__((unused)),
689 struct GNUNET_SERVER_Client *client,
690 const struct GNUNET_MessageHeader *message __attribute__((unused))) {
691 unhijack(dnsoutport);
692 GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
694 GNUNET_SERVER_receive_done(client, GNUNET_OK);
698 * This receives the dns-payload from the daemon-vpn and sends it on over the udp-socket
701 receive_query(void *cls __attribute__((unused)),
702 struct GNUNET_SERVER_Client *client,
703 const struct GNUNET_MessageHeader *message) {
704 struct query_packet* pkt = (struct query_packet*)message;
705 struct dns_pkt* dns = (struct dns_pkt*)pkt->data;
706 struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
708 query_states[dns->s.id].valid = GNUNET_YES;
709 query_states[dns->s.id].client = client;
710 query_states[dns->s.id].local_ip = pkt->orig_from;
711 query_states[dns->s.id].local_port = pkt->src_port;
712 query_states[dns->s.id].remote_ip = pkt->orig_to;
713 query_states[dns->s.id].namelen = strlen((char*)dns->data) + 1;
714 query_states[dns->s.id].name = GNUNET_malloc(query_states[dns->s.id].namelen);
715 memcpy(query_states[dns->s.id].name, dns->data, query_states[dns->s.id].namelen);
717 /* The query is for a .gnunet-address */
718 if (pdns->queries[0]->namelen > 9 &&
719 0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - 9), ".gnunet.", 9))
721 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for .gnunet!\n");
723 GNUNET_CRYPTO_hash(pdns->queries[0]->name, pdns->queries[0]->namelen, &key);
725 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
726 "Getting with key %08x, len is %d\n",
727 *((unsigned int*)&key),
728 pdns->queries[0]->namelen);
730 struct receive_dht_cls* cls = GNUNET_malloc(sizeof(struct receive_dht_cls));
733 cls->handle = GNUNET_DHT_get_start(dht,
734 GNUNET_TIME_UNIT_MINUTES,
735 GNUNET_BLOCK_TYPE_DNS,
737 DEFAULT_GET_REPLICATION,
749 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for '%s'; namelen=%d\n", pdns->queries[0]->name, pdns->queries[0]->namelen);
751 /* This is a PTR-Query. Check if it is for "our" network */
752 if (htons(pdns->queries[0]->qtype) == 12 &&
753 74 == pdns->queries[0]->namelen)
757 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.";
759 unsigned long long ipv6prefix;
760 unsigned int comparelen;
762 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_string(cfg, "vpn", "IPV6ADDR", &ipv6addr));
763 inet_pton (AF_INET6, ipv6addr, ipv6);
764 GNUNET_free(ipv6addr);
766 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_number(cfg, "vpn", "IPV6PREFIX", &ipv6prefix));
767 GNUNET_assert(ipv6prefix < 127);
768 ipv6prefix = (ipv6prefix + 7)/8;
770 for (i = ipv6prefix; i < 16; i++)
773 for (i = 0; i < 16; i++)
775 unsigned char c1 = ipv6[i] >> 4;
776 unsigned char c2 = ipv6[i] & 0xf;
779 ipv6rev[62-(4*i)] = c1 + '0';
781 ipv6rev[62-(4*i)] = c1 + 87; /* 87 is the difference between 'a' and 10 */
784 ipv6rev[62-((4*i)+2)] = c2 + '0';
786 ipv6rev[62-((4*i)+2)] = c2 + 87;
788 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "My network is %s'.\n", ipv6rev);
789 comparelen = 10 + 4*ipv6prefix;
790 if(0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - comparelen),
791 ipv6rev + (74 - comparelen),
794 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Reverse-Query for .gnunet!\n");
796 GNUNET_SCHEDULER_add_now(send_rev_query, pdns);
803 unsigned int virt_dns_bytes;
805 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
808 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
809 "No entry 'VIRTDNS' in configuration!\n");
813 if (1 != inet_pton (AF_INET, virt_dns, &virt_dns_bytes))
815 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
816 "Error parsing 'VIRTDNS': %s; %m!\n", virt_dns);
820 GNUNET_free(virt_dns);
822 if (virt_dns_bytes == pkt->orig_to)
824 /* This is a packet that was sent directly to the virtual dns-server
826 * This means we have to send this query over gnunet
829 size_t size = sizeof(struct GNUNET_MESH_Tunnel*) + sizeof(struct GNUNET_MessageHeader) + (ntohs(message->size) - sizeof(struct query_packet) + 1);
830 struct tunnel_cls *cls_ = GNUNET_malloc(size);
831 cls_->hdr.size = size - sizeof(struct GNUNET_MESH_Tunnel*);
833 cls_->hdr.type = ntohs(GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS);
834 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "size: %d\n", size);
836 memcpy(&cls_->dns, dns, cls_->hdr.size - sizeof(struct GNUNET_MessageHeader));
837 GNUNET_SCHEDULER_add_now(send_mesh_query, cls_);
843 /* The query should be sent to the network */
845 struct sockaddr_in dest;
846 memset(&dest, 0, sizeof dest);
847 dest.sin_port = htons(53);
848 dest.sin_addr.s_addr = pkt->orig_to;
850 GNUNET_NETWORK_socket_sendto(dnsout,
852 ntohs(pkt->hdr.size) - sizeof(struct query_packet) + 1,
853 (struct sockaddr*) &dest,
857 free_parsed_dns_packet(pdns);
860 GNUNET_SERVER_receive_done(client, GNUNET_OK);
863 static void read_response (void *cls,
864 const struct GNUNET_SCHEDULER_TaskContext *tc);
869 struct sockaddr_in addr;
871 dnsout = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
874 memset (&addr, 0, sizeof (struct sockaddr_in));
876 int err = GNUNET_NETWORK_socket_bind (dnsout,
877 (struct sockaddr *) &addr,
878 sizeof (struct sockaddr_in));
880 if (err != GNUNET_YES)
882 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
883 "Could not bind a port, exiting\n");
887 /* Read the port we bound to */
888 socklen_t addrlen = sizeof (struct sockaddr_in);
889 err = getsockname (GNUNET_NETWORK_get_fd (dnsout),
890 (struct sockaddr *) &addr, &addrlen);
892 dnsoutport = htons (addr.sin_port);
894 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, dnsout,
895 &read_response, NULL);
899 * Read a response-packet of the UDP-Socket
902 read_response (void *cls
903 __attribute__ ((unused)),
904 const struct GNUNET_SCHEDULER_TaskContext *tc)
906 struct sockaddr_in addr;
907 socklen_t addrlen = sizeof (addr);
911 if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
914 memset (&addr, 0, sizeof addr);
917 if (0 != ioctl (GNUNET_NETWORK_get_fd (dnsout), FIONREAD, &len))
919 unhijack (dnsoutport);
921 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
925 /* port the code above? */
929 unsigned char buf[len];
930 struct dns_pkt *dns = (struct dns_pkt *) buf;
932 r = GNUNET_NETWORK_socket_recvfrom (dnsout,
935 (struct sockaddr *) &addr, &addrlen);
939 unhijack (dnsoutport);
941 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
945 if (query_states[dns->s.id].valid == GNUNET_YES)
947 if (query_states[dns->s.id].tunnel != NULL)
949 /* This response should go through a tunnel */
950 uint32_t *c = GNUNET_malloc (4 + sizeof(struct GNUNET_MESH_Tunnel*) + r);
952 struct GNUNET_MESH_Tunnel** t = (struct GNUNET_MESH_Tunnel**)(c + 1);
953 *t = query_states[dns->s.id].tunnel;
954 memcpy (t + 1, dns, r);
956 GNUNET_MESH_tunnel_get_data (query_states[dns->s.id].tunnel))
958 struct GNUNET_MESH_TransmitHandle *th =
959 GNUNET_MESH_notify_transmit_ready (query_states[dns->s.id].tunnel,
962 GNUNET_TIME_UNIT_MINUTES,
966 GNUNET_MessageHeader),
967 mesh_send_response, c);
968 GNUNET_MESH_tunnel_set_data (query_states[dns->s.id].tunnel,
973 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(query_states[dns->s.id].tunnel);
974 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(query_states[dns->s.id].tunnel);
976 struct tunnel_notify_queue* element = GNUNET_malloc(sizeof(struct tunnel_notify_queue));
978 element->len = r+sizeof(struct GNUNET_MessageHeader);
979 element->cb = mesh_send_response;
981 GNUNET_CONTAINER_DLL_insert_tail(head, tail, element);
982 GNUNET_MESH_tunnel_set_head(query_states[dns->s.id].tunnel, head);
983 GNUNET_MESH_tunnel_set_tail(query_states[dns->s.id].tunnel, tail);
988 query_states[dns->s.id].valid = GNUNET_NO;
990 size_t len = sizeof (struct answer_packet) + r - 1; /* 1 for the unsigned char data[1]; */
991 struct answer_packet_list *answer =
992 GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
993 answer->pkt.hdr.type =
994 htons (GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
995 answer->pkt.hdr.size = htons (len);
996 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_IP;
997 answer->pkt.from = addr.sin_addr.s_addr;
998 answer->pkt.to = query_states[dns->s.id].local_ip;
999 answer->pkt.dst_port = query_states[dns->s.id].local_port;
1000 memcpy (answer->pkt.data, buf, r);
1002 GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
1004 GNUNET_SERVER_notify_transmit_ready (query_states
1005 [dns->s.id].client, len,
1006 GNUNET_TIME_UNIT_FOREVER_REL,
1008 query_states[dns->s.
1013 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
1014 dnsout, &read_response, NULL);
1019 * Task run during shutdown.
1025 cleanup_task (void *cls __attribute__((unused)),
1026 const struct GNUNET_SCHEDULER_TaskContext *tc)
1028 GNUNET_assert(0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
1030 unhijack(dnsoutport);
1031 GNUNET_DHT_disconnect(dht);
1035 * @brief Create a port-map from udp and tcp redirects
1037 * @param udp_redirects
1038 * @param tcp_redirects
1043 get_port_from_redirects (const char *udp_redirects, const char *tcp_redirects)
1046 char* cpy, *hostname, *redirect;
1047 int local_port, count = 0;
1049 if (NULL != udp_redirects)
1051 cpy = GNUNET_strdup (udp_redirects);
1052 for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
1054 if (NULL == (hostname = strstr (redirect, ":")))
1056 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
1060 local_port = atoi (redirect);
1061 if (!((local_port > 0) && (local_port < 65536)))
1062 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: %s is not a correct port.", redirect);
1064 ret |= (0xFFFF & htons(local_port));
1078 if (NULL != tcp_redirects)
1080 cpy = GNUNET_strdup (tcp_redirects);
1081 for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
1083 if (NULL == (hostname = strstr (redirect, ":")))
1085 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
1089 local_port = atoi (redirect);
1090 if (!((local_port > 0) && (local_port < 65536)))
1091 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: %s is not a correct port.", redirect);
1093 ret |= (0xFFFF & htons(local_port));
1114 publish_name (const char *name, uint64_t ports, uint32_t service_type,
1115 struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key)
1117 size_t size = sizeof (struct GNUNET_DNS_Record);
1118 struct GNUNET_DNS_Record data;
1119 memset (&data, 0, size);
1122 htonl (size - sizeof (struct GNUNET_CRYPTO_RsaSignature));
1123 data.purpose.purpose = GNUNET_SIGNATURE_PURPOSE_DNS_RECORD;
1125 GNUNET_CRYPTO_hash (name, strlen (name) + 1, &data.service_descriptor);
1126 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Store with key1 %x\n",
1127 *((unsigned long long *) &data.service_descriptor));
1129 data.service_type = service_type;
1132 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &data.peer);
1134 data.expiration_time =
1135 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_HOURS, 2));
1137 /* Sign the block */
1138 if (GNUNET_OK != GNUNET_CRYPTO_rsa_sign (my_private_key,
1139 &data.purpose, &data.signature))
1141 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not sign DNS_Record\n");
1145 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1146 "Putting with key %08x, size = %d\n",
1147 *((unsigned int *) &data.service_descriptor), size);
1149 GNUNET_DHT_put (dht,
1150 &data.service_descriptor,
1151 DEFAULT_PUT_REPLICATION,
1153 GNUNET_BLOCK_TYPE_DNS,
1156 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_HOURS),
1157 GNUNET_TIME_UNIT_MINUTES, NULL, NULL);
1161 * @brief Publishes the record defined by the section section
1163 * @param cls closure
1164 * @param section the current section
1167 publish_iterate (void *cls __attribute__((unused)), const char *section)
1169 if ((strlen(section) < 8) || (0 != strcmp (".gnunet.", section + (strlen(section) - 8))))
1172 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Parsing dns-name %s\n", section);
1174 char *udp_redirects, *tcp_redirects, *alternative_names, *alternative_name,
1177 GNUNET_CONFIGURATION_get_value_string (cfg, section,
1178 "UDP_REDIRECTS", &udp_redirects);
1179 GNUNET_CONFIGURATION_get_value_string (cfg, section, "TCP_REDIRECTS",
1182 if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_filename (cfg, "GNUNETD",
1186 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not read keyfile-value\n");
1187 if (keyfile != NULL)
1188 GNUNET_free (keyfile);
1192 struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key =
1193 GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
1194 GNUNET_free (keyfile);
1195 GNUNET_assert (my_private_key != NULL);
1197 uint64_t ports = get_port_from_redirects (udp_redirects, tcp_redirects);
1198 uint32_t service_type = 0;
1200 if (NULL != udp_redirects)
1201 service_type = GNUNET_DNS_SERVICE_TYPE_UDP;
1203 if (NULL != tcp_redirects)
1204 service_type |= GNUNET_DNS_SERVICE_TYPE_TCP;
1206 service_type = htonl (service_type);
1209 publish_name (section, ports, service_type, my_private_key);
1211 GNUNET_CONFIGURATION_get_value_string (cfg, section,
1212 "ALTERNATIVE_NAMES",
1213 &alternative_names);
1214 for (alternative_name = strtok (alternative_names, " ");
1215 alternative_name != NULL; alternative_name = strtok (NULL, " "))
1218 alloca (strlen (alternative_name) + strlen (section) + 1 + 1);
1219 strcpy (altname, alternative_name);
1220 strcpy (altname + strlen (alternative_name) + 1, section);
1221 altname[strlen (alternative_name)] = '.';
1223 publish_name (altname, ports, service_type, my_private_key);
1226 GNUNET_free_non_null(alternative_names);
1227 GNUNET_CRYPTO_rsa_key_free (my_private_key);
1228 GNUNET_free_non_null (udp_redirects);
1229 GNUNET_free_non_null (tcp_redirects);
1233 * Publish a DNS-record in the DHT.
1236 publish_names (void *cls __attribute__((unused)),
1237 const struct GNUNET_SCHEDULER_TaskContext *tc) {
1238 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1241 GNUNET_CONFIGURATION_iterate_sections(cfg, publish_iterate, NULL);
1243 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_HOURS,
1249 * @param cls closure
1250 * @param server the initialized server
1251 * @param cfg_ configuration to use
1255 struct GNUNET_SERVER_Handle *server,
1256 const struct GNUNET_CONFIGURATION_Handle *cfg_)
1258 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
1259 /* callback, cls, type, size */
1260 {&receive_query, NULL, GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS, 0},
1261 {&rehijack, NULL, GNUNET_MESSAGE_TYPE_REHIJACK,
1262 sizeof (struct GNUNET_MessageHeader)},
1266 static const struct GNUNET_MESH_MessageHandler mesh_handlers[] = {
1267 {receive_mesh_query, GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS, 0},
1268 {receive_mesh_answer, GNUNET_MESSAGE_TYPE_REMOTE_ANSWER_DNS, 0},
1272 static GNUNET_MESH_ApplicationType *apptypes;
1275 GNUNET_CONFIGURATION_get_value_yesno (cfg_, "dns", "PROVIDE_EXIT"))
1276 apptypes = (GNUNET_MESH_ApplicationType[])
1278 GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
1279 GNUNET_APPLICATION_TYPE_END};
1281 apptypes = (GNUNET_MESH_ApplicationType[])
1283 GNUNET_APPLICATION_TYPE_END};
1286 GNUNET_MESH_connect (cfg_, NULL, NULL, mesh_handlers, apptypes);
1291 for (i = 0; i < 65536; i++)
1293 query_states[i].valid = GNUNET_NO;
1296 dht = GNUNET_DHT_connect (cfg, 1024);
1300 GNUNET_SCHEDULER_add_now (publish_names, NULL);
1302 GNUNET_SERVER_add_handlers (server, handlers);
1303 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
1304 &cleanup_task, cls);
1308 * The main function for the dns service.
1310 * @param argc number of arguments from the command line
1311 * @param argv command line arguments
1312 * @return 0 ok, 1 on error
1315 main (int argc, char *const *argv)
1317 return (GNUNET_OK ==
1318 GNUNET_SERVICE_run (argc,
1321 GNUNET_SERVICE_OPTION_NONE,
1322 &run, NULL)) ? 0 : 1;