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);
246 if (NULL != GNUNET_MESH_tunnel_get_head(*tunnel))
248 struct tunnel_notify_queue* element = GNUNET_MESH_tunnel_get_head(*tunnel);
249 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(*tunnel);
250 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(*tunnel);
252 GNUNET_CONTAINER_DLL_remove(head, tail, element);
254 GNUNET_MESH_tunnel_set_head(*tunnel, head);
255 GNUNET_MESH_tunnel_set_tail(*tunnel, tail);
256 struct GNUNET_MESH_TransmitHandle* th = GNUNET_MESH_notify_transmit_ready (*tunnel,
259 GNUNET_TIME_relative_divide
260 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
261 (const struct GNUNET_PeerIdentity *)
263 element->cb, element->cls);
264 /* save the handle */
265 GNUNET_MESH_tunnel_set_data(*tunnel, th);
267 return ntohs (hdr->size);
271 mesh_send (void *cls, size_t size, void *buf)
273 struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
274 GNUNET_MESH_tunnel_set_data(cls_->tunnel, NULL);
276 GNUNET_assert(cls_->hdr.size <= size);
278 size = cls_->hdr.size;
279 cls_->hdr.size = htons(cls_->hdr.size);
281 memcpy(buf, &cls_->hdr, size);
283 if (NULL != GNUNET_MESH_tunnel_get_head(cls_->tunnel))
285 struct tunnel_notify_queue* element = GNUNET_MESH_tunnel_get_head(cls_->tunnel);
286 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(cls_->tunnel);
287 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(cls_->tunnel);
289 GNUNET_CONTAINER_DLL_remove(head, tail, element);
291 GNUNET_MESH_tunnel_set_head(cls_->tunnel, head);
292 GNUNET_MESH_tunnel_set_tail(cls_->tunnel, tail);
293 struct GNUNET_MESH_TransmitHandle* th = GNUNET_MESH_notify_transmit_ready (cls_->tunnel,
296 GNUNET_TIME_relative_divide
297 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
298 (const struct GNUNET_PeerIdentity *)
300 element->cb, element->cls);
301 /* save the handle */
302 GNUNET_MESH_tunnel_set_data(cls_->tunnel, th);
311 mesh_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
312 const struct GNUNET_TRANSPORT_ATS_Information *atsi
313 __attribute__ ((unused)))
317 struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
318 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
319 "Connected to peer %s, sending query with id %d\n",
320 GNUNET_i2s (peer), ntohs (cls_->dns.s.id));
322 if (NULL == GNUNET_MESH_tunnel_get_data (cls_->tunnel))
324 struct GNUNET_MESH_TransmitHandle *th =
325 GNUNET_MESH_notify_transmit_ready (cls_->tunnel,
328 GNUNET_TIME_UNIT_MINUTES,
334 GNUNET_MESH_tunnel_set_data (cls_->tunnel, th);
338 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(cls_->tunnel);
339 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(cls_->tunnel);
341 struct tunnel_notify_queue* element = GNUNET_malloc(sizeof(struct tunnel_notify_queue));
343 element->len = cls_->hdr.size;
344 element->cb = mesh_send;
346 GNUNET_CONTAINER_DLL_insert_tail(head, tail, element);
347 GNUNET_MESH_tunnel_set_head(cls_->tunnel, head);
348 GNUNET_MESH_tunnel_set_tail(cls_->tunnel, tail);
354 send_mesh_query (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
356 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
359 struct tunnel_cls *cls_ = (struct tunnel_cls*)cls;
361 if (NULL == dns_tunnel)
362 dns_tunnel = GNUNET_MESH_peer_request_connect_by_type(mesh_handle,
363 GNUNET_TIME_UNIT_HOURS,
364 GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
368 cls_->tunnel = dns_tunnel;
369 remote_pending[cls_->dns.s.id] = cls_;
373 receive_mesh_query (void *cls __attribute__((unused)),
374 struct GNUNET_MESH_Tunnel *tunnel,
375 void **ctx __attribute__((unused)),
376 const struct GNUNET_PeerIdentity *sender __attribute__((unused)),
377 const struct GNUNET_MessageHeader *message,
378 const struct GNUNET_TRANSPORT_ATS_Information *atsi __attribute__((unused)))
380 struct dns_pkt *dns = (struct dns_pkt*)(message + 1);
382 struct sockaddr_in dest;
383 memset(&dest, 0, sizeof dest);
384 dest.sin_port = htons(53);
385 /* TODO: read from config */
386 inet_pton(AF_INET, "8.8.8.8", &dest.sin_addr);
388 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Querying for remote, id=%d\n", ntohs(dns->s.id));
389 query_states[dns->s.id].tunnel = tunnel;
390 query_states[dns->s.id].valid = GNUNET_YES;
392 GNUNET_NETWORK_socket_sendto(dnsout,
394 ntohs(message->size) - sizeof(struct GNUNET_MessageHeader),
395 (struct sockaddr*) &dest,
398 return GNUNET_SYSERR;
402 receive_mesh_answer (void *cls __attribute__((unused)),
403 struct GNUNET_MESH_Tunnel *tunnel,
404 void **ctx __attribute__((unused)),
405 const struct GNUNET_PeerIdentity *sender,
406 const struct GNUNET_MessageHeader *message,
407 const struct GNUNET_TRANSPORT_ATS_Information *atsi __attribute__((unused)))
409 /* TODo: size check */
410 struct dns_pkt *dns = (struct dns_pkt *) (message + 1);
412 /* They sent us a packet we were not waiting for */
413 if (remote_pending[dns->s.id] == NULL
414 || remote_pending[dns->s.id]->tunnel != tunnel)
415 return GNUNET_SYSERR;
416 if (query_states[dns->s.id].valid != GNUNET_YES)
417 return GNUNET_SYSERR;
418 query_states[dns->s.id].valid = GNUNET_NO;
420 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Received answer from peer %s, dns-id %d\n", GNUNET_i2s(sender), ntohs(dns->s.id));
422 size_t len = sizeof (struct answer_packet) - 1 + sizeof (struct dns_static) + query_states[dns->s.id].namelen + sizeof (struct dns_query_line) + 2 /* To hold the pointer (as defined in RFC1035) to the name */
423 + sizeof (struct dns_record_line) - 1 + 16; /* To hold the IPv6-Address */
425 struct answer_packet_list *answer =
426 GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
427 memset (answer, 0, len + 2 * sizeof (struct answer_packet_list *));
429 answer->pkt.hdr.type = htons (GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
430 answer->pkt.hdr.size = htons (len);
431 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REMOTE;
433 struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
435 if (ntohs(pdns->s.ancount) < 1)
437 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer only contains %d answers.\n", ntohs(pdns->s.ancount));
438 free_parsed_dns_packet(pdns);
442 answer->pkt.addrsize = ntohs(pdns->answers[0]->data_len);
443 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "The first answer has the addrlen %d\n", answer->pkt.addrsize);
444 memcpy(answer->pkt.addr, pdns->answers[0]->data, ntohs(pdns->answers[0]->data_len));
446 answer->pkt.from = query_states[dns->s.id].remote_ip;
448 answer->pkt.to = query_states[dns->s.id].local_ip;
449 answer->pkt.dst_port = query_states[dns->s.id].local_port;
451 struct dns_pkt *dpkt = (struct dns_pkt *) answer->pkt.data;
453 dpkt->s.id = dns->s.id;
457 dpkt->s.qdcount = htons (1);
458 dpkt->s.ancount = htons (1);
460 memcpy (dpkt->data, query_states[dns->s.id].name,
461 query_states[dns->s.id].namelen);
462 GNUNET_free (query_states[dns->s.id].name);
464 struct dns_query_line *dque =
465 (struct dns_query_line *) (dpkt->data +
466 (query_states[dns->s.id].namelen));
467 dque->type = htons (28); /* AAAA */
468 dque->class = htons (1); /* IN */
471 (char *) (dpkt->data + (query_states[dns->s.id].namelen) +
472 sizeof (struct dns_query_line));
473 memcpy (anname, "\xc0\x0c", 2);
475 struct dns_record_line *drec_data =
476 (struct dns_record_line *) (dpkt->data +
477 (query_states[dns->s.id].namelen) +
478 sizeof (struct dns_query_line) + 2);
479 drec_data->type = htons (28); /* AAAA */
480 drec_data->class = htons (1); /* IN */
482 drec_data->ttl = pdns->answers[0]->ttl;
483 drec_data->data_len = htons (16);
485 /* Calculate at which offset in the packet the IPv6-Address belongs, it is
486 * filled in by the daemon-vpn */
487 answer->pkt.addroffset =
488 htons ((unsigned short) ((unsigned long) (&drec_data->data) -
489 (unsigned long) (&answer->pkt)));
491 GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
493 GNUNET_SERVER_notify_transmit_ready (query_states[dns->s.id].client,
495 GNUNET_TIME_UNIT_FOREVER_REL,
497 query_states[dns->s.id].client);
499 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sent answer of length %d on to client, addroffset = %d\n", len, answer->pkt.addroffset);
501 free_parsed_dns_packet(pdns);
507 send_rev_query(void * cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
508 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
511 struct dns_pkt_parsed* pdns = (struct dns_pkt_parsed*) cls;
513 unsigned short id = pdns->s.id;
515 free_parsed_dns_packet(pdns);
517 if (query_states[id].valid != GNUNET_YES) return;
518 query_states[id].valid = GNUNET_NO;
520 GNUNET_assert(query_states[id].namelen == 74);
522 size_t len = sizeof(struct answer_packet) - 1 \
523 + sizeof(struct dns_static) \
524 + 74 /* this is the length of a reverse ipv6-lookup */ \
525 + sizeof(struct dns_query_line) \
526 + 2 /* To hold the pointer (as defined in RFC1035) to the name */ \
527 + sizeof(struct dns_record_line) - 1 \
528 - 2 /* We do not know the lenght of the answer yet*/;
530 struct answer_packet_list* answer = GNUNET_malloc(len + 2*sizeof(struct answer_packet_list*));
531 memset(answer, 0, len + 2*sizeof(struct answer_packet_list*));
533 answer->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
534 answer->pkt.hdr.size = htons(len);
535 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REV;
537 answer->pkt.from = query_states[id].remote_ip;
539 answer->pkt.to = query_states[id].local_ip;
540 answer->pkt.dst_port = query_states[id].local_port;
542 struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
548 dpkt->s.qdcount = htons(1);
549 dpkt->s.ancount = htons(1);
551 memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
552 GNUNET_free(query_states[id].name);
554 struct dns_query_line* dque = (struct dns_query_line*)(dpkt->data+(query_states[id].namelen));
555 dque->type = htons(12); /* PTR */
556 dque->class = htons(1); /* IN */
558 char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
559 memcpy(anname, "\xc0\x0c", 2);
561 struct dns_record_line *drec_data = (struct dns_record_line*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line)+2);
562 drec_data->type = htons(12); /* AAAA */
563 drec_data->class = htons(1); /* IN */
564 /* FIXME: read the TTL from block:
565 * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
567 * But how to get the seconds out of this?
569 drec_data->ttl = htonl(3600);
571 /* Calculate at which offset in the packet the length of the name and the
572 * name, it is filled in by the daemon-vpn */
573 answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data_len)-(unsigned long)(&answer->pkt)));
575 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
577 GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
579 GNUNET_TIME_UNIT_FOREVER_REL,
581 query_states[id].client);
585 * Receive a block from the dht.
588 receive_dht(void *cls,
589 struct GNUNET_TIME_Absolute exp __attribute__((unused)),
590 const GNUNET_HashCode *key __attribute__((unused)),
591 const struct GNUNET_PeerIdentity *const *get_path __attribute__((unused)),
592 const struct GNUNET_PeerIdentity *const *put_path __attribute__((unused)),
593 enum GNUNET_BLOCK_Type type,
597 unsigned short id = ((struct receive_dht_cls*)cls)->id;
598 struct GNUNET_DHT_GetHandle* handle = ((struct receive_dht_cls*)cls)->handle;
601 GNUNET_assert(type == GNUNET_BLOCK_TYPE_DNS);
603 /* If no query with this id is pending, ignore the block */
604 if (query_states[id].valid != GNUNET_YES) return;
605 query_states[id].valid = GNUNET_NO;
607 const struct GNUNET_DNS_Record* rec = data;
608 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
609 "Got block of size %d, peer: %08x, desc: %08x\n",
611 *((unsigned int*)&rec->peer),
612 *((unsigned int*)&rec->service_descriptor));
614 size_t len = sizeof(struct answer_packet) - 1 \
615 + sizeof(struct dns_static) \
616 + query_states[id].namelen \
617 + sizeof(struct dns_query_line) \
618 + 2 /* To hold the pointer (as defined in RFC1035) to the name */ \
619 + sizeof(struct dns_record_line) - 1 \
620 + 16; /* To hold the IPv6-Address */
622 struct answer_packet_list* answer = GNUNET_malloc(len + 2*sizeof(struct answer_packet_list*));
623 memset(answer, 0, len + 2*sizeof(struct answer_packet_list*));
625 answer->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
626 answer->pkt.hdr.size = htons(len);
627 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_SERVICE;
629 GNUNET_CRYPTO_hash(&rec->peer,
630 sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
631 &answer->pkt.service_descr.peer);
633 memcpy(&answer->pkt.service_descr.service_descriptor,
634 &rec->service_descriptor,
635 sizeof(GNUNET_HashCode));
636 memcpy(&answer->pkt.service_descr.service_type,
638 sizeof(answer->pkt.service_descr.service_type));
639 memcpy(&answer->pkt.service_descr.ports, &rec->ports, sizeof(answer->pkt.service_descr.ports));
641 answer->pkt.from = query_states[id].remote_ip;
643 answer->pkt.to = query_states[id].local_ip;
644 answer->pkt.dst_port = query_states[id].local_port;
646 struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
652 dpkt->s.qdcount = htons(1);
653 dpkt->s.ancount = htons(1);
655 memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
656 GNUNET_free(query_states[id].name);
658 struct dns_query_line* dque = (struct dns_query_line*)(dpkt->data+(query_states[id].namelen));
659 dque->type = htons(28); /* AAAA */
660 dque->class = htons(1); /* IN */
662 char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
663 memcpy(anname, "\xc0\x0c", 2);
665 struct dns_record_line *drec_data = (struct dns_record_line*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line)+2);
666 drec_data->type = htons(28); /* AAAA */
667 drec_data->class = htons(1); /* IN */
669 /* FIXME: read the TTL from block:
670 * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
672 * But how to get the seconds out of this?
674 drec_data->ttl = htonl(3600);
675 drec_data->data_len = htons(16);
677 /* Calculate at which offset in the packet the IPv6-Address belongs, it is
678 * filled in by the daemon-vpn */
679 answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data)-(unsigned long)(&answer->pkt)));
681 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
683 GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
685 GNUNET_TIME_UNIT_FOREVER_REL,
687 query_states[id].client);
689 GNUNET_DHT_get_stop(handle);
693 * This receives a GNUNET_MESSAGE_TYPE_REHIJACK and rehijacks the DNS
696 rehijack(void *cls __attribute__((unused)),
697 struct GNUNET_SERVER_Client *client,
698 const struct GNUNET_MessageHeader *message __attribute__((unused))) {
699 unhijack(dnsoutport);
700 GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
702 GNUNET_SERVER_receive_done(client, GNUNET_OK);
706 * This receives the dns-payload from the daemon-vpn and sends it on over the udp-socket
709 receive_query(void *cls __attribute__((unused)),
710 struct GNUNET_SERVER_Client *client,
711 const struct GNUNET_MessageHeader *message) {
712 struct query_packet* pkt = (struct query_packet*)message;
713 struct dns_pkt* dns = (struct dns_pkt*)pkt->data;
714 struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
716 query_states[dns->s.id].valid = GNUNET_YES;
717 query_states[dns->s.id].client = client;
718 query_states[dns->s.id].local_ip = pkt->orig_from;
719 query_states[dns->s.id].local_port = pkt->src_port;
720 query_states[dns->s.id].remote_ip = pkt->orig_to;
721 query_states[dns->s.id].namelen = strlen((char*)dns->data) + 1;
722 query_states[dns->s.id].name = GNUNET_malloc(query_states[dns->s.id].namelen);
723 memcpy(query_states[dns->s.id].name, dns->data, query_states[dns->s.id].namelen);
725 /* The query is for a .gnunet-address */
726 if (pdns->queries[0]->namelen > 9 &&
727 0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - 9), ".gnunet.", 9))
729 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for .gnunet!\n");
731 GNUNET_CRYPTO_hash(pdns->queries[0]->name, pdns->queries[0]->namelen, &key);
733 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
734 "Getting with key %08x, len is %d\n",
735 *((unsigned int*)&key),
736 pdns->queries[0]->namelen);
738 struct receive_dht_cls* cls = GNUNET_malloc(sizeof(struct receive_dht_cls));
741 cls->handle = GNUNET_DHT_get_start(dht,
742 GNUNET_TIME_UNIT_MINUTES,
743 GNUNET_BLOCK_TYPE_DNS,
745 DEFAULT_GET_REPLICATION,
757 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for '%s'; namelen=%d\n", pdns->queries[0]->name, pdns->queries[0]->namelen);
759 /* This is a PTR-Query. Check if it is for "our" network */
760 if (htons(pdns->queries[0]->qtype) == 12 &&
761 74 == pdns->queries[0]->namelen)
765 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.";
767 unsigned long long ipv6prefix;
768 unsigned int comparelen;
770 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_string(cfg, "vpn", "IPV6ADDR", &ipv6addr));
771 inet_pton (AF_INET6, ipv6addr, ipv6);
772 GNUNET_free(ipv6addr);
774 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_number(cfg, "vpn", "IPV6PREFIX", &ipv6prefix));
775 GNUNET_assert(ipv6prefix < 127);
776 ipv6prefix = (ipv6prefix + 7)/8;
778 for (i = ipv6prefix; i < 16; i++)
781 for (i = 0; i < 16; i++)
783 unsigned char c1 = ipv6[i] >> 4;
784 unsigned char c2 = ipv6[i] & 0xf;
787 ipv6rev[62-(4*i)] = c1 + '0';
789 ipv6rev[62-(4*i)] = c1 + 87; /* 87 is the difference between 'a' and 10 */
792 ipv6rev[62-((4*i)+2)] = c2 + '0';
794 ipv6rev[62-((4*i)+2)] = c2 + 87;
796 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "My network is %s'.\n", ipv6rev);
797 comparelen = 10 + 4*ipv6prefix;
798 if(0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - comparelen),
799 ipv6rev + (74 - comparelen),
802 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Reverse-Query for .gnunet!\n");
804 GNUNET_SCHEDULER_add_now(send_rev_query, pdns);
811 unsigned int virt_dns_bytes;
813 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
816 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
817 "No entry 'VIRTDNS' in configuration!\n");
821 if (1 != inet_pton (AF_INET, virt_dns, &virt_dns_bytes))
823 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
824 "Error parsing 'VIRTDNS': %s; %m!\n", virt_dns);
828 GNUNET_free(virt_dns);
830 if (virt_dns_bytes == pkt->orig_to)
832 /* This is a packet that was sent directly to the virtual dns-server
834 * This means we have to send this query over gnunet
837 size_t size = sizeof(struct GNUNET_MESH_Tunnel*) + sizeof(struct GNUNET_MessageHeader) + (ntohs(message->size) - sizeof(struct query_packet) + 1);
838 struct tunnel_cls *cls_ = GNUNET_malloc(size);
839 cls_->hdr.size = size - sizeof(struct GNUNET_MESH_Tunnel*);
841 cls_->hdr.type = ntohs(GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS);
842 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "size: %d\n", size);
844 memcpy(&cls_->dns, dns, cls_->hdr.size - sizeof(struct GNUNET_MessageHeader));
845 GNUNET_SCHEDULER_add_now(send_mesh_query, cls_);
851 /* The query should be sent to the network */
853 struct sockaddr_in dest;
854 memset(&dest, 0, sizeof dest);
855 dest.sin_port = htons(53);
856 dest.sin_addr.s_addr = pkt->orig_to;
858 GNUNET_NETWORK_socket_sendto(dnsout,
860 ntohs(pkt->hdr.size) - sizeof(struct query_packet) + 1,
861 (struct sockaddr*) &dest,
865 free_parsed_dns_packet(pdns);
868 GNUNET_SERVER_receive_done(client, GNUNET_OK);
871 static void read_response (void *cls,
872 const struct GNUNET_SCHEDULER_TaskContext *tc);
877 struct sockaddr_in addr;
879 dnsout = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
881 return GNUNET_SYSERR;
882 memset (&addr, 0, sizeof (struct sockaddr_in));
884 addr.sin_family = AF_INET;
885 int err = GNUNET_NETWORK_socket_bind (dnsout,
886 (struct sockaddr *) &addr,
887 sizeof (struct sockaddr_in));
889 if (err != GNUNET_OK)
891 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
892 "Could not bind a port: %m\n");
893 return GNUNET_SYSERR;
896 /* Read the port we bound to */
897 socklen_t addrlen = sizeof (struct sockaddr_in);
898 err = getsockname (GNUNET_NETWORK_get_fd (dnsout),
899 (struct sockaddr *) &addr, &addrlen);
901 dnsoutport = htons (addr.sin_port);
903 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Bound to port %d.\n", dnsoutport);
905 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, dnsout,
906 &read_response, NULL);
912 * Read a response-packet of the UDP-Socket
915 read_response (void *cls
916 __attribute__ ((unused)),
917 const struct GNUNET_SCHEDULER_TaskContext *tc)
919 struct sockaddr_in addr;
920 socklen_t addrlen = sizeof (addr);
924 if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
927 memset (&addr, 0, sizeof addr);
930 if (0 != ioctl (GNUNET_NETWORK_get_fd (dnsout), FIONREAD, &len))
932 unhijack (dnsoutport);
933 if (GNUNET_YES == open_port ())
934 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
938 /* port the code above? */
942 unsigned char buf[len];
943 struct dns_pkt *dns = (struct dns_pkt *) buf;
945 r = GNUNET_NETWORK_socket_recvfrom (dnsout,
948 (struct sockaddr *) &addr, &addrlen);
952 unhijack (dnsoutport);
953 if (GNUNET_YES == open_port ())
954 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
958 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer to query %d\n", ntohs(dns->s.id));
960 if (query_states[dns->s.id].valid == GNUNET_YES)
962 if (query_states[dns->s.id].tunnel != NULL)
964 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer to query %d for a remote peer!\n", ntohs(dns->s.id));
965 /* This response should go through a tunnel */
966 uint32_t *c = GNUNET_malloc (4 + sizeof(struct GNUNET_MESH_Tunnel*) + r);
968 struct GNUNET_MESH_Tunnel** t = (struct GNUNET_MESH_Tunnel**)(c + 1);
969 *t = query_states[dns->s.id].tunnel;
970 memcpy (t + 1, dns, r);
972 GNUNET_MESH_tunnel_get_data (query_states[dns->s.id].tunnel))
974 struct GNUNET_MESH_TransmitHandle *th =
975 GNUNET_MESH_notify_transmit_ready (query_states[dns->s.id].tunnel,
978 GNUNET_TIME_UNIT_MINUTES,
982 GNUNET_MessageHeader),
983 mesh_send_response, c);
984 GNUNET_MESH_tunnel_set_data (query_states[dns->s.id].tunnel,
989 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(query_states[dns->s.id].tunnel);
990 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(query_states[dns->s.id].tunnel);
992 struct tunnel_notify_queue* element = GNUNET_malloc(sizeof(struct tunnel_notify_queue));
994 element->len = r+sizeof(struct GNUNET_MessageHeader);
995 element->cb = mesh_send_response;
997 GNUNET_CONTAINER_DLL_insert_tail(head, tail, element);
998 GNUNET_MESH_tunnel_set_head(query_states[dns->s.id].tunnel, head);
999 GNUNET_MESH_tunnel_set_tail(query_states[dns->s.id].tunnel, tail);
1004 query_states[dns->s.id].valid = GNUNET_NO;
1006 size_t len = sizeof (struct answer_packet) + r - 1; /* 1 for the unsigned char data[1]; */
1007 struct answer_packet_list *answer =
1008 GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
1009 answer->pkt.hdr.type =
1010 htons (GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
1011 answer->pkt.hdr.size = htons (len);
1012 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_IP;
1013 answer->pkt.from = addr.sin_addr.s_addr;
1014 answer->pkt.to = query_states[dns->s.id].local_ip;
1015 answer->pkt.dst_port = query_states[dns->s.id].local_port;
1016 memcpy (answer->pkt.data, buf, r);
1018 GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
1020 GNUNET_SERVER_notify_transmit_ready (query_states
1021 [dns->s.id].client, len,
1022 GNUNET_TIME_UNIT_FOREVER_REL,
1024 query_states[dns->s.
1029 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
1030 dnsout, &read_response, NULL);
1035 * Task run during shutdown.
1041 cleanup_task (void *cls __attribute__((unused)),
1042 const struct GNUNET_SCHEDULER_TaskContext *tc)
1044 GNUNET_assert(0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
1046 unhijack(dnsoutport);
1047 GNUNET_DHT_disconnect(dht);
1051 * @brief Create a port-map from udp and tcp redirects
1053 * @param udp_redirects
1054 * @param tcp_redirects
1059 get_port_from_redirects (const char *udp_redirects, const char *tcp_redirects)
1062 char* cpy, *hostname, *redirect;
1063 int local_port, count = 0;
1065 if (NULL != udp_redirects)
1067 cpy = GNUNET_strdup (udp_redirects);
1068 for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
1070 if (NULL == (hostname = strstr (redirect, ":")))
1072 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
1076 local_port = atoi (redirect);
1077 if (!((local_port > 0) && (local_port < 65536)))
1078 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: %s is not a correct port.", redirect);
1080 ret |= (0xFFFF & htons(local_port));
1094 if (NULL != tcp_redirects)
1096 cpy = GNUNET_strdup (tcp_redirects);
1097 for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
1099 if (NULL == (hostname = strstr (redirect, ":")))
1101 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
1105 local_port = atoi (redirect);
1106 if (!((local_port > 0) && (local_port < 65536)))
1107 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: %s is not a correct port.", redirect);
1109 ret |= (0xFFFF & htons(local_port));
1130 publish_name (const char *name, uint64_t ports, uint32_t service_type,
1131 struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key)
1133 size_t size = sizeof (struct GNUNET_DNS_Record);
1134 struct GNUNET_DNS_Record data;
1135 memset (&data, 0, size);
1138 htonl (size - sizeof (struct GNUNET_CRYPTO_RsaSignature));
1139 data.purpose.purpose = GNUNET_SIGNATURE_PURPOSE_DNS_RECORD;
1141 GNUNET_CRYPTO_hash (name, strlen (name) + 1, &data.service_descriptor);
1142 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Store with key1 %x\n",
1143 *((unsigned long long *) &data.service_descriptor));
1145 data.service_type = service_type;
1148 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &data.peer);
1150 data.expiration_time =
1151 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_HOURS, 2));
1153 /* Sign the block */
1154 if (GNUNET_OK != GNUNET_CRYPTO_rsa_sign (my_private_key,
1155 &data.purpose, &data.signature))
1157 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not sign DNS_Record\n");
1161 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1162 "Putting with key %08x, size = %d\n",
1163 *((unsigned int *) &data.service_descriptor), size);
1165 GNUNET_DHT_put (dht,
1166 &data.service_descriptor,
1167 DEFAULT_PUT_REPLICATION,
1169 GNUNET_BLOCK_TYPE_DNS,
1172 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_HOURS),
1173 GNUNET_TIME_UNIT_MINUTES, NULL, NULL);
1177 * @brief Publishes the record defined by the section section
1179 * @param cls closure
1180 * @param section the current section
1183 publish_iterate (void *cls __attribute__((unused)), const char *section)
1185 if ((strlen(section) < 8) || (0 != strcmp (".gnunet.", section + (strlen(section) - 8))))
1188 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Parsing dns-name %s\n", section);
1190 char *udp_redirects, *tcp_redirects, *alternative_names, *alternative_name,
1193 GNUNET_CONFIGURATION_get_value_string (cfg, section,
1194 "UDP_REDIRECTS", &udp_redirects);
1195 GNUNET_CONFIGURATION_get_value_string (cfg, section, "TCP_REDIRECTS",
1198 if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_filename (cfg, "GNUNETD",
1202 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not read keyfile-value\n");
1203 if (keyfile != NULL)
1204 GNUNET_free (keyfile);
1208 struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key =
1209 GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
1210 GNUNET_free (keyfile);
1211 GNUNET_assert (my_private_key != NULL);
1213 uint64_t ports = get_port_from_redirects (udp_redirects, tcp_redirects);
1214 uint32_t service_type = 0;
1216 if (NULL != udp_redirects)
1217 service_type = GNUNET_DNS_SERVICE_TYPE_UDP;
1219 if (NULL != tcp_redirects)
1220 service_type |= GNUNET_DNS_SERVICE_TYPE_TCP;
1222 service_type = htonl (service_type);
1225 publish_name (section, ports, service_type, my_private_key);
1227 GNUNET_CONFIGURATION_get_value_string (cfg, section,
1228 "ALTERNATIVE_NAMES",
1229 &alternative_names);
1230 for (alternative_name = strtok (alternative_names, " ");
1231 alternative_name != NULL; alternative_name = strtok (NULL, " "))
1234 alloca (strlen (alternative_name) + strlen (section) + 1 + 1);
1235 strcpy (altname, alternative_name);
1236 strcpy (altname + strlen (alternative_name) + 1, section);
1237 altname[strlen (alternative_name)] = '.';
1239 publish_name (altname, ports, service_type, my_private_key);
1242 GNUNET_free_non_null(alternative_names);
1243 GNUNET_CRYPTO_rsa_key_free (my_private_key);
1244 GNUNET_free_non_null (udp_redirects);
1245 GNUNET_free_non_null (tcp_redirects);
1249 * Publish a DNS-record in the DHT.
1252 publish_names (void *cls __attribute__((unused)),
1253 const struct GNUNET_SCHEDULER_TaskContext *tc) {
1254 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1257 GNUNET_CONFIGURATION_iterate_sections(cfg, publish_iterate, NULL);
1259 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_HOURS,
1265 * @param cls closure
1266 * @param server the initialized server
1267 * @param cfg_ configuration to use
1271 struct GNUNET_SERVER_Handle *server,
1272 const struct GNUNET_CONFIGURATION_Handle *cfg_)
1274 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
1275 /* callback, cls, type, size */
1276 {&receive_query, NULL, GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS, 0},
1277 {&rehijack, NULL, GNUNET_MESSAGE_TYPE_REHIJACK,
1278 sizeof (struct GNUNET_MessageHeader)},
1282 static const struct GNUNET_MESH_MessageHandler mesh_handlers[] = {
1283 {receive_mesh_query, GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS, 0},
1284 {receive_mesh_answer, GNUNET_MESSAGE_TYPE_REMOTE_ANSWER_DNS, 0},
1288 static GNUNET_MESH_ApplicationType *apptypes;
1290 if (GNUNET_YES != open_port ())
1292 GNUNET_SCHEDULER_shutdown();
1297 GNUNET_CONFIGURATION_get_value_yesno (cfg_, "dns", "PROVIDE_EXIT"))
1298 apptypes = (GNUNET_MESH_ApplicationType[])
1300 GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
1301 GNUNET_APPLICATION_TYPE_END};
1303 apptypes = (GNUNET_MESH_ApplicationType[])
1305 GNUNET_APPLICATION_TYPE_END};
1308 GNUNET_MESH_connect (cfg_, NULL, NULL, mesh_handlers, apptypes);
1313 for (i = 0; i < 65536; i++)
1315 query_states[i].valid = GNUNET_NO;
1318 dht = GNUNET_DHT_connect (cfg, 1024);
1320 GNUNET_SCHEDULER_add_now (publish_names, NULL);
1322 GNUNET_SERVER_add_handlers (server, handlers);
1323 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
1324 &cleanup_task, cls);
1328 * The main function for the dns service.
1330 * @param argc number of arguments from the command line
1331 * @param argv command line arguments
1332 * @return 0 ok, 1 on error
1335 main (int argc, char *const *argv)
1337 return (GNUNET_OK ==
1338 GNUNET_SERVICE_run (argc,
1341 GNUNET_SERVICE_OPTION_NONE,
1342 &run, NULL)) ? 0 : 1;