2 This file is part of GNUnet.
3 (C) 2009 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file vpn/gnunet-service-dns.c
23 * @author Philipp Toelke
26 #include "gnunet_getopt_lib.h"
27 #include "gnunet_service_lib.h"
28 #include <gnunet_constants.h>
29 #include "gnunet_network_lib.h"
30 #include "gnunet_os_lib.h"
31 #include "gnunet-service-dns-p.h"
32 #include "gnunet_protocols.h"
33 #include "gnunet_applications.h"
34 #include "gnunet-vpn-packet.h"
35 #include "gnunet_container_lib.h"
36 #include "gnunet-dns-parser.h"
37 #include "gnunet_dht_service.h"
38 #include "gnunet_block_lib.h"
39 #include "block_dns.h"
40 #include "gnunet_crypto_lib.h"
41 #include "gnunet_mesh_service.h"
42 #include "gnunet_signatures.h"
44 struct GNUNET_MESH_Handle *mesh_handle;
47 * The tunnel to send queries
49 static struct GNUNET_MESH_Tunnel* dns_tunnel;
52 * The UDP-Socket through which DNS-Resolves will be sent if they are not to be
53 * sent through gnunet. The port of this socket will not be hijacked.
55 static struct GNUNET_NETWORK_Handle *dnsout;
58 * The port bound to the socket dnsout
60 static unsigned short dnsoutport;
63 * A handle to the DHT-Service
65 static struct GNUNET_DHT_Handle *dht;
68 * The configuration to use
70 static const struct GNUNET_CONFIGURATION_Handle *cfg;
73 * A list of DNS-Responses that have to be sent to the requesting client
75 static struct answer_packet_list *head;
78 * The tail of the list of DNS-responses
80 static struct answer_packet_list *tail;
83 * A structure containing a mapping from network-byte-ordered DNS-id (16 bit) to
84 * some information needed to handle this query
86 * It currently allocates at least
87 * (1 + machine-width + machine-width + 32 + 32 + 16 + machine-width + 8) * 65536 bit
93 struct GNUNET_SERVER_Client* client;
94 struct GNUNET_MESH_Tunnel *tunnel;
100 } query_states[UINT16_MAX];
103 * A struct used to give more than one value as
104 * closure to receive_dht
106 struct receive_dht_cls {
108 struct GNUNET_DHT_GetHandle* handle;
111 struct tunnel_notify_queue
113 struct tunnel_notify_queue* next;
114 struct tunnel_notify_queue* prev;
117 GNUNET_CONNECTION_TransmitReadyNotify cb;
121 * Hijack all outgoing DNS-Traffic but for traffic leaving "our" port.
124 hijack (void *cls __attribute__((unused)), const struct GNUNET_SCHEDULER_TaskContext *tc)
126 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
131 GNUNET_log(GNUNET_ERROR_TYPE_INFO, "Delaying the hijacking, port is still %d!\n", dnsoutport);
132 GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
138 struct GNUNET_OS_Process *proc;
141 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
144 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
145 "No entry 'VIRTDNS' in configuration!\n");
149 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Hijacking, port is %d\n", dnsoutport);
150 snprintf (port_s, 6, "%d", dnsoutport);
151 if (NULL != (proc = GNUNET_OS_start_process (NULL,
153 "gnunet-helper-hijack-dns",
155 port_s, virt_dns, NULL)))
156 GNUNET_OS_process_close (proc);
157 GNUNET_free (virt_dns);
161 * Delete the hijacking-routes
164 unhijack (unsigned short port)
168 struct GNUNET_OS_Process *proc;
171 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
174 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
175 "No entry 'VIRTDNS' in configuration!\n");
179 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "unHijacking, port is %d\n", port);
180 snprintf (port_s, 6, "%d", port);
181 if (NULL != (proc = GNUNET_OS_start_process (NULL,
183 "gnunet-helper-hijack-dns",
185 "-d", port_s, virt_dns, NULL)))
186 GNUNET_OS_process_close (proc);
187 GNUNET_free (virt_dns);
191 * Send the DNS-Response to the client. Gets called via the notify_transmit_ready-
195 send_answer(void* cls, size_t size, void* buf) {
196 struct answer_packet_list* query = head;
197 size_t len = ntohs(query->pkt.hdr.size);
199 GNUNET_assert(len <= size);
201 memcpy(buf, &query->pkt.hdr, len);
203 GNUNET_CONTAINER_DLL_remove (head, tail, query);
207 /* When more data is to be sent, reschedule */
209 GNUNET_SERVER_notify_transmit_ready(cls,
210 ntohs(head->pkt.hdr.size),
211 GNUNET_TIME_UNIT_FOREVER_REL,
219 struct GNUNET_MESH_Tunnel *tunnel GNUNET_PACKED;
220 struct GNUNET_MessageHeader hdr;
224 struct tunnel_cls *remote_pending[UINT16_MAX];
227 mesh_send_response (void *cls, size_t size, void *buf)
229 GNUNET_assert (size >= sizeof (struct GNUNET_MessageHeader));
230 struct GNUNET_MessageHeader *hdr = buf;
232 struct GNUNET_MESH_Tunnel **tunnel = (struct GNUNET_MESH_Tunnel**)(sz+1);
233 struct dns_pkt *dns = (struct dns_pkt *) (tunnel + 1);
234 hdr->type = htons (GNUNET_MESSAGE_TYPE_REMOTE_ANSWER_DNS);
235 hdr->size = htons (*sz + sizeof (struct GNUNET_MessageHeader));
237 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
238 "Sending response, size=%d, sz=%d, sz+hdr=%d\n", size, *sz,
239 *sz + sizeof (struct GNUNET_MessageHeader));
241 GNUNET_assert (size >= (*sz + sizeof (struct GNUNET_MessageHeader)));
243 memcpy (hdr + 1, dns, *sz);
245 if (NULL != GNUNET_MESH_tunnel_get_head(*tunnel))
247 struct tunnel_notify_queue* element = GNUNET_MESH_tunnel_get_head(*tunnel);
248 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(*tunnel);
249 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(*tunnel);
251 GNUNET_CONTAINER_DLL_remove(head, tail, element);
253 GNUNET_MESH_tunnel_set_head(*tunnel, head);
254 GNUNET_MESH_tunnel_set_tail(*tunnel, tail);
255 struct GNUNET_MESH_TransmitHandle* th = GNUNET_MESH_notify_transmit_ready (*tunnel,
258 GNUNET_TIME_relative_divide
259 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
260 (const struct GNUNET_PeerIdentity *)
262 element->cb, element->cls);
263 /* save the handle */
264 GNUNET_MESH_tunnel_set_data(*tunnel, th);
269 return ntohs (hdr->size);
273 mesh_send (void *cls, size_t size, void *buf)
275 struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
276 GNUNET_MESH_tunnel_set_data(cls_->tunnel, NULL);
278 GNUNET_assert(cls_->hdr.size <= size);
280 size = cls_->hdr.size;
281 cls_->hdr.size = htons(cls_->hdr.size);
283 memcpy(buf, &cls_->hdr, size);
285 if (NULL != GNUNET_MESH_tunnel_get_head(cls_->tunnel))
287 struct tunnel_notify_queue* element = GNUNET_MESH_tunnel_get_head(cls_->tunnel);
288 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(cls_->tunnel);
289 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(cls_->tunnel);
291 GNUNET_CONTAINER_DLL_remove(head, tail, element);
293 GNUNET_MESH_tunnel_set_head(cls_->tunnel, head);
294 GNUNET_MESH_tunnel_set_tail(cls_->tunnel, tail);
295 struct GNUNET_MESH_TransmitHandle* th = GNUNET_MESH_notify_transmit_ready (cls_->tunnel,
298 GNUNET_TIME_relative_divide
299 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
300 (const struct GNUNET_PeerIdentity *)
302 element->cb, element->cls);
303 /* save the handle */
304 GNUNET_MESH_tunnel_set_data(cls_->tunnel, th);
312 mesh_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
313 const struct GNUNET_TRANSPORT_ATS_Information *atsi
314 __attribute__ ((unused)))
318 struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
319 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
320 "Connected to peer %s, sending query with id %d\n",
321 GNUNET_i2s (peer), ntohs (cls_->dns.s.id));
323 if (NULL == GNUNET_MESH_tunnel_get_data (cls_->tunnel))
325 struct GNUNET_MESH_TransmitHandle *th =
326 GNUNET_MESH_notify_transmit_ready (cls_->tunnel,
329 GNUNET_TIME_UNIT_MINUTES,
335 GNUNET_MESH_tunnel_set_data (cls_->tunnel, th);
339 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(cls_->tunnel);
340 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(cls_->tunnel);
342 struct tunnel_notify_queue* element = GNUNET_malloc(sizeof(struct tunnel_notify_queue));
344 element->len = cls_->hdr.size;
345 element->cb = mesh_send;
347 GNUNET_CONTAINER_DLL_insert_tail(head, tail, element);
348 GNUNET_MESH_tunnel_set_head(cls_->tunnel, head);
349 GNUNET_MESH_tunnel_set_tail(cls_->tunnel, tail);
355 send_mesh_query (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
357 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
360 struct tunnel_cls *cls_ = (struct tunnel_cls*)cls;
362 if (NULL == dns_tunnel)
363 dns_tunnel = GNUNET_MESH_peer_request_connect_by_type(mesh_handle,
364 GNUNET_TIME_UNIT_HOURS,
365 GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
369 cls_->tunnel = dns_tunnel;
370 remote_pending[cls_->dns.s.id] = cls_;
374 receive_mesh_query (void *cls __attribute__((unused)),
375 struct GNUNET_MESH_Tunnel *tunnel,
376 void **ctx __attribute__((unused)),
377 const struct GNUNET_PeerIdentity *sender __attribute__((unused)),
378 const struct GNUNET_MessageHeader *message,
379 const struct GNUNET_TRANSPORT_ATS_Information *atsi __attribute__((unused)))
381 struct dns_pkt *dns = (struct dns_pkt*)(message + 1);
383 struct sockaddr_in dest;
384 memset(&dest, 0, sizeof dest);
385 dest.sin_port = htons(53);
386 /* TODO: read from config */
387 inet_pton(AF_INET, "8.8.8.8", &dest.sin_addr);
389 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Querying for remote, id=%d\n", ntohs(dns->s.id));
390 query_states[dns->s.id].tunnel = tunnel;
391 query_states[dns->s.id].valid = GNUNET_YES;
393 GNUNET_NETWORK_socket_sendto(dnsout,
395 ntohs(message->size) - sizeof(struct GNUNET_MessageHeader),
396 (struct sockaddr*) &dest,
399 return GNUNET_SYSERR;
403 receive_mesh_answer (void *cls __attribute__((unused)),
404 struct GNUNET_MESH_Tunnel *tunnel,
405 void **ctx __attribute__((unused)),
406 const struct GNUNET_PeerIdentity *sender,
407 const struct GNUNET_MessageHeader *message,
408 const struct GNUNET_TRANSPORT_ATS_Information *atsi __attribute__((unused)))
410 /* TODo: size check */
411 struct dns_pkt *dns = (struct dns_pkt *) (message + 1);
413 /* They sent us a packet we were not waiting for */
414 if (remote_pending[dns->s.id] == NULL
415 || remote_pending[dns->s.id]->tunnel != tunnel)
418 GNUNET_free(remote_pending[dns->s.id]);
419 remote_pending[dns->s.id] = NULL;
421 if (query_states[dns->s.id].valid != GNUNET_YES)
422 return GNUNET_SYSERR;
423 query_states[dns->s.id].valid = GNUNET_NO;
425 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Received answer from peer %s, dns-id %d\n", GNUNET_i2s(sender), ntohs(dns->s.id));
427 size_t len = sizeof (struct answer_packet) - 1 + sizeof (struct dns_static) + query_states[dns->s.id].namelen + sizeof (struct dns_query_line) + 2 /* To hold the pointer (as defined in RFC1035) to the name */
428 + sizeof (struct dns_record_line) - 1 + 16; /* To hold the IPv6-Address */
430 struct answer_packet_list *answer =
431 GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
432 memset (answer, 0, len + 2 * sizeof (struct answer_packet_list *));
434 answer->pkt.hdr.type = htons (GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
435 answer->pkt.hdr.size = htons (len);
437 struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
439 if (ntohs(pdns->s.ancount) < 1)
441 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer only contains %d answers.\n", ntohs(pdns->s.ancount));
442 free_parsed_dns_packet(pdns);
446 answer->pkt.addrsize = ntohs(pdns->answers[0]->data_len);
447 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "The first answer has the addrlen %d\n", answer->pkt.addrsize);
448 memcpy(answer->pkt.addr, pdns->answers[0]->data, ntohs(pdns->answers[0]->data_len));
450 answer->pkt.from = query_states[dns->s.id].remote_ip;
452 answer->pkt.to = query_states[dns->s.id].local_ip;
453 answer->pkt.dst_port = query_states[dns->s.id].local_port;
455 struct dns_pkt *dpkt = (struct dns_pkt *) answer->pkt.data;
457 dpkt->s.id = dns->s.id;
461 dpkt->s.qdcount = htons (1);
462 dpkt->s.ancount = htons (1);
464 memcpy (dpkt->data, query_states[dns->s.id].name,
465 query_states[dns->s.id].namelen);
466 GNUNET_free (query_states[dns->s.id].name);
468 struct dns_query_line *dque =
469 (struct dns_query_line *) (dpkt->data +
470 (query_states[dns->s.id].namelen));
471 if (16 == answer->pkt.addrsize)
473 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REMOTE_AAAA;
474 dque->type = htons (28); /* AAAA */
478 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REMOTE_A;
479 dque->type = htons (1); /* A */
481 dque->class = htons (1); /* IN */
484 (char *) (dpkt->data + (query_states[dns->s.id].namelen) +
485 sizeof (struct dns_query_line));
486 memcpy (anname, "\xc0\x0c", 2);
488 struct dns_record_line *drec_data =
489 (struct dns_record_line *) (dpkt->data +
490 (query_states[dns->s.id].namelen) +
491 sizeof (struct dns_query_line) + 2);
492 drec_data->type = htons (28); /* AAAA */
493 drec_data->class = htons (1); /* IN */
495 drec_data->ttl = pdns->answers[0]->ttl;
496 drec_data->data_len = htons (16);
498 /* Calculate at which offset in the packet the IPv6-Address belongs, it is
499 * filled in by the daemon-vpn */
500 answer->pkt.addroffset =
501 htons ((unsigned short) ((unsigned long) (&drec_data->data) -
502 (unsigned long) (&answer->pkt)));
504 GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
506 GNUNET_SERVER_notify_transmit_ready (query_states[dns->s.id].client,
508 GNUNET_TIME_UNIT_FOREVER_REL,
510 query_states[dns->s.id].client);
512 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sent answer of length %d on to client, addroffset = %d\n", len, answer->pkt.addroffset);
514 free_parsed_dns_packet(pdns);
520 send_rev_query(void * cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
521 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
524 struct dns_pkt_parsed* pdns = (struct dns_pkt_parsed*) cls;
526 unsigned short id = pdns->s.id;
528 free_parsed_dns_packet(pdns);
530 if (query_states[id].valid != GNUNET_YES) return;
531 query_states[id].valid = GNUNET_NO;
533 GNUNET_assert(query_states[id].namelen == 74);
535 size_t len = sizeof(struct answer_packet) - 1 \
536 + sizeof(struct dns_static) \
537 + 74 /* this is the length of a reverse ipv6-lookup */ \
538 + sizeof(struct dns_query_line) \
539 + 2 /* To hold the pointer (as defined in RFC1035) to the name */ \
540 + sizeof(struct dns_record_line) - 1 \
541 - 2 /* We do not know the lenght of the answer yet*/;
543 struct answer_packet_list* answer = GNUNET_malloc(len + 2*sizeof(struct answer_packet_list*));
544 memset(answer, 0, len + 2*sizeof(struct answer_packet_list*));
546 answer->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
547 answer->pkt.hdr.size = htons(len);
548 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REV;
550 answer->pkt.from = query_states[id].remote_ip;
552 answer->pkt.to = query_states[id].local_ip;
553 answer->pkt.dst_port = query_states[id].local_port;
555 struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
561 dpkt->s.qdcount = htons(1);
562 dpkt->s.ancount = htons(1);
564 memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
565 GNUNET_free(query_states[id].name);
567 struct dns_query_line* dque = (struct dns_query_line*)(dpkt->data+(query_states[id].namelen));
568 dque->type = htons(12); /* PTR */
569 dque->class = htons(1); /* IN */
571 char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
572 memcpy(anname, "\xc0\x0c", 2);
574 struct dns_record_line *drec_data = (struct dns_record_line*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line)+2);
575 drec_data->type = htons(12); /* AAAA */
576 drec_data->class = htons(1); /* IN */
577 /* FIXME: read the TTL from block:
578 * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
580 * But how to get the seconds out of this?
582 drec_data->ttl = htonl(3600);
584 /* Calculate at which offset in the packet the length of the name and the
585 * name, it is filled in by the daemon-vpn */
586 answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data_len)-(unsigned long)(&answer->pkt)));
588 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
590 GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
592 GNUNET_TIME_UNIT_FOREVER_REL,
594 query_states[id].client);
598 * Receive a block from the dht.
601 receive_dht(void *cls,
602 struct GNUNET_TIME_Absolute exp __attribute__((unused)),
603 const GNUNET_HashCode *key __attribute__((unused)),
604 const struct GNUNET_PeerIdentity *const *get_path __attribute__((unused)),
605 const struct GNUNET_PeerIdentity *const *put_path __attribute__((unused)),
606 enum GNUNET_BLOCK_Type type,
610 unsigned short id = ((struct receive_dht_cls*)cls)->id;
611 struct GNUNET_DHT_GetHandle* handle = ((struct receive_dht_cls*)cls)->handle;
614 GNUNET_assert(type == GNUNET_BLOCK_TYPE_DNS);
616 /* If no query with this id is pending, ignore the block */
617 if (query_states[id].valid != GNUNET_YES) return;
618 query_states[id].valid = GNUNET_NO;
620 const struct GNUNET_DNS_Record* rec = data;
621 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
622 "Got block of size %d, peer: %08x, desc: %08x\n",
624 *((unsigned int*)&rec->peer),
625 *((unsigned int*)&rec->service_descriptor));
627 size_t len = sizeof(struct answer_packet) - 1 \
628 + sizeof(struct dns_static) \
629 + query_states[id].namelen \
630 + sizeof(struct dns_query_line) \
631 + 2 /* To hold the pointer (as defined in RFC1035) to the name */ \
632 + sizeof(struct dns_record_line) - 1 \
633 + 16; /* To hold the IPv6-Address */
635 struct answer_packet_list* answer = GNUNET_malloc(len + 2*sizeof(struct answer_packet_list*));
636 memset(answer, 0, len + 2*sizeof(struct answer_packet_list*));
638 answer->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
639 answer->pkt.hdr.size = htons(len);
640 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_SERVICE;
642 GNUNET_CRYPTO_hash(&rec->peer,
643 sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
644 &answer->pkt.service_descr.peer);
646 memcpy(&answer->pkt.service_descr.service_descriptor,
647 &rec->service_descriptor,
648 sizeof(GNUNET_HashCode));
649 memcpy(&answer->pkt.service_descr.service_type,
651 sizeof(answer->pkt.service_descr.service_type));
652 memcpy(&answer->pkt.service_descr.ports, &rec->ports, sizeof(answer->pkt.service_descr.ports));
654 answer->pkt.from = query_states[id].remote_ip;
656 answer->pkt.to = query_states[id].local_ip;
657 answer->pkt.dst_port = query_states[id].local_port;
659 struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
665 dpkt->s.qdcount = htons(1);
666 dpkt->s.ancount = htons(1);
668 memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
669 GNUNET_free(query_states[id].name);
671 struct dns_query_line* dque = (struct dns_query_line*)(dpkt->data+(query_states[id].namelen));
672 dque->type = htons(28); /* AAAA */
673 dque->class = htons(1); /* IN */
675 char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
676 memcpy(anname, "\xc0\x0c", 2);
678 struct dns_record_line *drec_data = (struct dns_record_line*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line)+2);
679 drec_data->type = htons(28); /* AAAA */
680 drec_data->class = htons(1); /* IN */
682 /* FIXME: read the TTL from block:
683 * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
685 * But how to get the seconds out of this?
687 drec_data->ttl = htonl(3600);
688 drec_data->data_len = htons(16);
690 /* Calculate at which offset in the packet the IPv6-Address belongs, it is
691 * filled in by the daemon-vpn */
692 answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data)-(unsigned long)(&answer->pkt)));
694 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
696 GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
698 GNUNET_TIME_UNIT_FOREVER_REL,
700 query_states[id].client);
702 GNUNET_DHT_get_stop(handle);
706 * This receives a GNUNET_MESSAGE_TYPE_REHIJACK and rehijacks the DNS
709 rehijack(void *cls __attribute__((unused)),
710 struct GNUNET_SERVER_Client *client,
711 const struct GNUNET_MessageHeader *message __attribute__((unused))) {
712 unhijack(dnsoutport);
713 GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
715 GNUNET_SERVER_receive_done(client, GNUNET_OK);
719 * This receives the dns-payload from the daemon-vpn and sends it on over the udp-socket
722 receive_query(void *cls __attribute__((unused)),
723 struct GNUNET_SERVER_Client *client,
724 const struct GNUNET_MessageHeader *message) {
725 struct query_packet* pkt = (struct query_packet*)message;
726 struct dns_pkt* dns = (struct dns_pkt*)pkt->data;
727 struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
729 query_states[dns->s.id].valid = GNUNET_YES;
730 query_states[dns->s.id].client = client;
731 query_states[dns->s.id].local_ip = pkt->orig_from;
732 query_states[dns->s.id].local_port = pkt->src_port;
733 query_states[dns->s.id].remote_ip = pkt->orig_to;
734 query_states[dns->s.id].namelen = strlen((char*)dns->data) + 1;
735 query_states[dns->s.id].name = GNUNET_malloc(query_states[dns->s.id].namelen);
736 memcpy(query_states[dns->s.id].name, dns->data, query_states[dns->s.id].namelen);
738 /* The query is for a .gnunet-address */
739 if (pdns->queries[0]->namelen > 9 &&
740 0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - 9), ".gnunet.", 9))
742 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for .gnunet!\n");
744 GNUNET_CRYPTO_hash(pdns->queries[0]->name, pdns->queries[0]->namelen, &key);
746 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
747 "Getting with key %08x, len is %d\n",
748 *((unsigned int*)&key),
749 pdns->queries[0]->namelen);
751 struct receive_dht_cls* cls = GNUNET_malloc(sizeof(struct receive_dht_cls));
754 cls->handle = GNUNET_DHT_get_start(dht,
755 GNUNET_TIME_UNIT_MINUTES,
756 GNUNET_BLOCK_TYPE_DNS,
758 DEFAULT_GET_REPLICATION,
770 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for '%s'; namelen=%d\n", pdns->queries[0]->name, pdns->queries[0]->namelen);
772 /* This is a PTR-Query. Check if it is for "our" network */
773 if (htons(pdns->queries[0]->qtype) == 12 &&
774 74 == pdns->queries[0]->namelen)
778 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.";
780 unsigned long long ipv6prefix;
781 unsigned int comparelen;
783 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_string(cfg, "vpn", "IPV6ADDR", &ipv6addr));
784 inet_pton (AF_INET6, ipv6addr, ipv6);
785 GNUNET_free(ipv6addr);
787 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_number(cfg, "vpn", "IPV6PREFIX", &ipv6prefix));
788 GNUNET_assert(ipv6prefix < 127);
789 ipv6prefix = (ipv6prefix + 7)/8;
791 for (i = ipv6prefix; i < 16; i++)
794 for (i = 0; i < 16; i++)
796 unsigned char c1 = ipv6[i] >> 4;
797 unsigned char c2 = ipv6[i] & 0xf;
800 ipv6rev[62-(4*i)] = c1 + '0';
802 ipv6rev[62-(4*i)] = c1 + 87; /* 87 is the difference between 'a' and 10 */
805 ipv6rev[62-((4*i)+2)] = c2 + '0';
807 ipv6rev[62-((4*i)+2)] = c2 + 87;
809 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "My network is %s'.\n", ipv6rev);
810 comparelen = 10 + 4*ipv6prefix;
811 if(0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - comparelen),
812 ipv6rev + (74 - comparelen),
815 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Reverse-Query for .gnunet!\n");
817 GNUNET_SCHEDULER_add_now(send_rev_query, pdns);
824 unsigned int virt_dns_bytes;
826 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
829 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
830 "No entry 'VIRTDNS' in configuration!\n");
834 if (1 != inet_pton (AF_INET, virt_dns, &virt_dns_bytes))
836 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
837 "Error parsing 'VIRTDNS': %s; %m!\n", virt_dns);
841 GNUNET_free(virt_dns);
843 if (virt_dns_bytes == pkt->orig_to)
845 /* This is a packet that was sent directly to the virtual dns-server
847 * This means we have to send this query over gnunet
850 size_t size = sizeof(struct GNUNET_MESH_Tunnel*) + sizeof(struct GNUNET_MessageHeader) + (ntohs(message->size) - sizeof(struct query_packet) + 1);
851 struct tunnel_cls *cls_ = GNUNET_malloc(size);
852 cls_->hdr.size = size - sizeof(struct GNUNET_MESH_Tunnel*);
854 cls_->hdr.type = ntohs(GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS);
855 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "size: %d\n", size);
857 memcpy(&cls_->dns, dns, cls_->hdr.size - sizeof(struct GNUNET_MessageHeader));
858 GNUNET_SCHEDULER_add_now(send_mesh_query, cls_);
864 /* The query should be sent to the network */
866 struct sockaddr_in dest;
867 memset(&dest, 0, sizeof dest);
868 dest.sin_port = htons(53);
869 dest.sin_addr.s_addr = pkt->orig_to;
871 GNUNET_NETWORK_socket_sendto(dnsout,
873 ntohs(pkt->hdr.size) - sizeof(struct query_packet) + 1,
874 (struct sockaddr*) &dest,
878 free_parsed_dns_packet(pdns);
881 GNUNET_SERVER_receive_done(client, GNUNET_OK);
884 static void read_response (void *cls,
885 const struct GNUNET_SCHEDULER_TaskContext *tc);
890 struct sockaddr_in addr;
892 dnsout = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
894 return GNUNET_SYSERR;
895 memset (&addr, 0, sizeof (struct sockaddr_in));
897 addr.sin_family = AF_INET;
898 int err = GNUNET_NETWORK_socket_bind (dnsout,
899 (struct sockaddr *) &addr,
900 sizeof (struct sockaddr_in));
902 if (err != GNUNET_OK)
904 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
905 "Could not bind a port: %m\n");
906 return GNUNET_SYSERR;
909 /* Read the port we bound to */
910 socklen_t addrlen = sizeof (struct sockaddr_in);
911 err = getsockname (GNUNET_NETWORK_get_fd (dnsout),
912 (struct sockaddr *) &addr, &addrlen);
914 dnsoutport = htons (addr.sin_port);
916 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Bound to port %d.\n", dnsoutport);
918 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, dnsout,
919 &read_response, NULL);
925 * Read a response-packet of the UDP-Socket
928 read_response (void *cls
929 __attribute__ ((unused)),
930 const struct GNUNET_SCHEDULER_TaskContext *tc)
932 struct sockaddr_in addr;
933 socklen_t addrlen = sizeof (addr);
937 if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
940 memset (&addr, 0, sizeof addr);
943 if (0 != ioctl (GNUNET_NETWORK_get_fd (dnsout), FIONREAD, &len))
945 unhijack (dnsoutport);
946 if (GNUNET_YES == open_port ())
947 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
951 /* port the code above? */
955 unsigned char buf[len];
956 struct dns_pkt *dns = (struct dns_pkt *) buf;
958 r = GNUNET_NETWORK_socket_recvfrom (dnsout,
961 (struct sockaddr *) &addr, &addrlen);
965 unhijack (dnsoutport);
966 if (GNUNET_YES == open_port ())
967 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
971 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer to query %d\n", ntohs(dns->s.id));
973 if (query_states[dns->s.id].valid == GNUNET_YES)
975 if (query_states[dns->s.id].tunnel != NULL)
977 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answer to query %d for a remote peer!\n", ntohs(dns->s.id));
978 /* This response should go through a tunnel */
979 uint32_t *c = GNUNET_malloc (4 + sizeof(struct GNUNET_MESH_Tunnel*) + r);
981 struct GNUNET_MESH_Tunnel** t = (struct GNUNET_MESH_Tunnel**)(c + 1);
982 *t = query_states[dns->s.id].tunnel;
983 memcpy (t + 1, dns, r);
985 GNUNET_MESH_tunnel_get_data (query_states[dns->s.id].tunnel))
987 struct GNUNET_MESH_TransmitHandle *th =
988 GNUNET_MESH_notify_transmit_ready (query_states[dns->s.id].tunnel,
991 GNUNET_TIME_UNIT_MINUTES,
995 GNUNET_MessageHeader),
996 mesh_send_response, c);
997 GNUNET_MESH_tunnel_set_data (query_states[dns->s.id].tunnel,
1002 struct tunnel_notify_queue* head = GNUNET_MESH_tunnel_get_head(query_states[dns->s.id].tunnel);
1003 struct tunnel_notify_queue* tail = GNUNET_MESH_tunnel_get_tail(query_states[dns->s.id].tunnel);
1005 struct tunnel_notify_queue* element = GNUNET_malloc(sizeof(struct tunnel_notify_queue));
1007 element->len = r+sizeof(struct GNUNET_MessageHeader);
1008 element->cb = mesh_send_response;
1010 GNUNET_CONTAINER_DLL_insert_tail(head, tail, element);
1011 GNUNET_MESH_tunnel_set_head(query_states[dns->s.id].tunnel, head);
1012 GNUNET_MESH_tunnel_set_tail(query_states[dns->s.id].tunnel, tail);
1017 query_states[dns->s.id].valid = GNUNET_NO;
1019 size_t len = sizeof (struct answer_packet) + r - 1; /* 1 for the unsigned char data[1]; */
1020 struct answer_packet_list *answer =
1021 GNUNET_malloc (len + 2 * sizeof (struct answer_packet_list *));
1022 answer->pkt.hdr.type =
1023 htons (GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
1024 answer->pkt.hdr.size = htons (len);
1025 answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_IP;
1026 answer->pkt.from = addr.sin_addr.s_addr;
1027 answer->pkt.to = query_states[dns->s.id].local_ip;
1028 answer->pkt.dst_port = query_states[dns->s.id].local_port;
1029 memcpy (answer->pkt.data, buf, r);
1031 GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
1033 GNUNET_SERVER_notify_transmit_ready (query_states
1034 [dns->s.id].client, len,
1035 GNUNET_TIME_UNIT_FOREVER_REL,
1037 query_states[dns->s.
1042 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
1043 dnsout, &read_response, NULL);
1048 * Task run during shutdown.
1054 cleanup_task (void *cls __attribute__((unused)),
1055 const struct GNUNET_SCHEDULER_TaskContext *tc)
1057 GNUNET_assert(0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
1059 unhijack(dnsoutport);
1060 GNUNET_DHT_disconnect(dht);
1064 * @brief Create a port-map from udp and tcp redirects
1066 * @param udp_redirects
1067 * @param tcp_redirects
1072 get_port_from_redirects (const char *udp_redirects, const char *tcp_redirects)
1075 char* cpy, *hostname, *redirect;
1076 int local_port, count = 0;
1078 if (NULL != udp_redirects)
1080 cpy = GNUNET_strdup (udp_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));
1107 if (NULL != tcp_redirects)
1109 cpy = GNUNET_strdup (tcp_redirects);
1110 for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
1112 if (NULL == (hostname = strstr (redirect, ":")))
1114 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
1118 local_port = atoi (redirect);
1119 if (!((local_port > 0) && (local_port < 65536)))
1120 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: %s is not a correct port.", redirect);
1122 ret |= (0xFFFF & htons(local_port));
1143 publish_name (const char *name, uint64_t ports, uint32_t service_type,
1144 struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key)
1146 size_t size = sizeof (struct GNUNET_DNS_Record);
1147 struct GNUNET_DNS_Record data;
1148 memset (&data, 0, size);
1151 htonl (size - sizeof (struct GNUNET_CRYPTO_RsaSignature));
1152 data.purpose.purpose = GNUNET_SIGNATURE_PURPOSE_DNS_RECORD;
1154 GNUNET_CRYPTO_hash (name, strlen (name) + 1, &data.service_descriptor);
1155 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Store with key1 %x\n",
1156 *((unsigned long long *) &data.service_descriptor));
1158 data.service_type = service_type;
1161 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &data.peer);
1163 data.expiration_time =
1164 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_HOURS, 2));
1166 /* Sign the block */
1167 if (GNUNET_OK != GNUNET_CRYPTO_rsa_sign (my_private_key,
1168 &data.purpose, &data.signature))
1170 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not sign DNS_Record\n");
1174 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1175 "Putting with key %08x, size = %d\n",
1176 *((unsigned int *) &data.service_descriptor), size);
1178 GNUNET_DHT_put (dht,
1179 &data.service_descriptor,
1180 DEFAULT_PUT_REPLICATION,
1182 GNUNET_BLOCK_TYPE_DNS,
1185 GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_HOURS),
1186 GNUNET_TIME_UNIT_MINUTES, NULL, NULL);
1190 * @brief Publishes the record defined by the section section
1192 * @param cls closure
1193 * @param section the current section
1196 publish_iterate (void *cls __attribute__((unused)), const char *section)
1198 if ((strlen(section) < 8) || (0 != strcmp (".gnunet.", section + (strlen(section) - 8))))
1201 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Parsing dns-name %s\n", section);
1203 char *udp_redirects, *tcp_redirects, *alternative_names, *alternative_name,
1206 GNUNET_CONFIGURATION_get_value_string (cfg, section,
1207 "UDP_REDIRECTS", &udp_redirects);
1208 GNUNET_CONFIGURATION_get_value_string (cfg, section, "TCP_REDIRECTS",
1211 if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_filename (cfg, "GNUNETD",
1215 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not read keyfile-value\n");
1216 if (keyfile != NULL)
1217 GNUNET_free (keyfile);
1221 struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key =
1222 GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
1223 GNUNET_free (keyfile);
1224 GNUNET_assert (my_private_key != NULL);
1226 uint64_t ports = get_port_from_redirects (udp_redirects, tcp_redirects);
1227 uint32_t service_type = 0;
1229 if (NULL != udp_redirects)
1230 service_type = GNUNET_DNS_SERVICE_TYPE_UDP;
1232 if (NULL != tcp_redirects)
1233 service_type |= GNUNET_DNS_SERVICE_TYPE_TCP;
1235 service_type = htonl (service_type);
1238 publish_name (section, ports, service_type, my_private_key);
1240 GNUNET_CONFIGURATION_get_value_string (cfg, section,
1241 "ALTERNATIVE_NAMES",
1242 &alternative_names);
1243 for (alternative_name = strtok (alternative_names, " ");
1244 alternative_name != NULL; alternative_name = strtok (NULL, " "))
1247 alloca (strlen (alternative_name) + strlen (section) + 1 + 1);
1248 strcpy (altname, alternative_name);
1249 strcpy (altname + strlen (alternative_name) + 1, section);
1250 altname[strlen (alternative_name)] = '.';
1252 publish_name (altname, ports, service_type, my_private_key);
1255 GNUNET_free_non_null(alternative_names);
1256 GNUNET_CRYPTO_rsa_key_free (my_private_key);
1257 GNUNET_free_non_null (udp_redirects);
1258 GNUNET_free_non_null (tcp_redirects);
1262 * Publish a DNS-record in the DHT.
1265 publish_names (void *cls __attribute__((unused)),
1266 const struct GNUNET_SCHEDULER_TaskContext *tc) {
1267 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1270 GNUNET_CONFIGURATION_iterate_sections(cfg, publish_iterate, NULL);
1272 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_HOURS,
1278 * @param cls closure
1279 * @param server the initialized server
1280 * @param cfg_ configuration to use
1284 struct GNUNET_SERVER_Handle *server,
1285 const struct GNUNET_CONFIGURATION_Handle *cfg_)
1287 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
1288 /* callback, cls, type, size */
1289 {&receive_query, NULL, GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS, 0},
1290 {&rehijack, NULL, GNUNET_MESSAGE_TYPE_REHIJACK,
1291 sizeof (struct GNUNET_MessageHeader)},
1295 static const struct GNUNET_MESH_MessageHandler mesh_handlers[] = {
1296 {receive_mesh_query, GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS, 0},
1297 {receive_mesh_answer, GNUNET_MESSAGE_TYPE_REMOTE_ANSWER_DNS, 0},
1301 static GNUNET_MESH_ApplicationType *apptypes;
1303 if (GNUNET_YES != open_port ())
1305 GNUNET_SCHEDULER_shutdown();
1310 GNUNET_CONFIGURATION_get_value_yesno (cfg_, "dns", "PROVIDE_EXIT"))
1311 apptypes = (GNUNET_MESH_ApplicationType[])
1313 GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
1314 GNUNET_APPLICATION_TYPE_END};
1316 apptypes = (GNUNET_MESH_ApplicationType[])
1318 GNUNET_APPLICATION_TYPE_END};
1321 GNUNET_MESH_connect (cfg_, NULL, NULL, mesh_handlers, apptypes);
1326 for (i = 0; i < 65536; i++)
1328 query_states[i].valid = GNUNET_NO;
1331 dht = GNUNET_DHT_connect (cfg, 1024);
1333 GNUNET_SCHEDULER_add_now (publish_names, NULL);
1335 GNUNET_SERVER_add_handlers (server, handlers);
1336 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
1337 &cleanup_task, cls);
1341 * The main function for the dns service.
1343 * @param argc number of arguments from the command line
1344 * @param argv command line arguments
1345 * @return 0 ok, 1 on error
1348 main (int argc, char *const *argv)
1350 return (GNUNET_OK ==
1351 GNUNET_SERVICE_run (argc,
1354 GNUNET_SERVICE_OPTION_NONE,
1355 &run, NULL)) ? 0 : 1;